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http://mathhelpforum.com/pre-calculus/204446-preparing-calculus.html | # Math Help - Preparing for Calculus
1. ## Preparing for Calculus
Hello everyone,
I have a simple question, because I started college and I'm taking a Precalculus course.
Sadly is a very independent course... no homework, exercises, etc. Just a do whatever you want course with two grades midterm and final.
Are there any terms that come up in most Calculus courses?
Terms which I should look more into?
My book contains all of the following...
1. Graphs
1.1 The Distance and Midpoint Formulas; Graphing Utilities; Introduction to Graphing Equations
1.2 Intercepts; Symmetry; Graphing Key Equations
1.3 Solving Equations Using a Graphing Utility
1.4 Lines
1.5 Circles
Chapter Review
Chapter Test
Cumulative Review
Chapter Projects
2. Functions and Their Graphs
2.1 Functions
2.2 The Graph of a Function
2.3 Properties of Functions
2.4 Library of Functions; Piecewise-defined Functions
2.5 Graphing Techniques: Transformations
2.6 Mathematical Models: Building Functions
Chapter Review
Chapter Test
Cumulative Review
Chapter Projects
3.1 Linear Functions, Their Properties, and Linear Models
3.2 Building Linear Models from Data
3.3 Quadratic Functions and Their Properties
3.4 Building Quadratic Models from Verbal Descriptions and Data
Chapter Review
Chapter Test
Cumulative Review
Chapter Projects
4. Polynomial and Rational Functions
4.1 Polynomial Functions and Models
4.2 The Real Zeros of a Polynomial Function
4.3 Properties of Rational Functions
4.4 The Graph of a Rational Function
4.5 Polynomial and Rational Inequalities
4.6 Complex Zeros; Fundamental Theorem of Algebra
Chapter Review
Chapter Test
Cumulative Review
Chapter Projects
5. Exponential and Logarithmic Functions
5.1 Composite Functions
5.2 One-to-One Functions; Inverse Functions
5.3 Exponential Functions
5.4 Logarithmic Functions
5.5 Properties of Logarithms
5.6 Logarithmic and Exponential Equations
5.7 Financial Models
5.8 Exponential Growth and Decay Models; Newton's Law; Logistic Growth and Decay Models
5.9 Building Exponential, Logarithmic, and Logistic Models from Data
Chapter Review
Chapter Test
Cumulative Review
Chapter Projects
6. Trigonometric Functions
6.1 Angles and Their Measure
6.2 Trigonometric Functions: Unit Circle Approach
6.3 Properties of the Trigonometric Functions
6.4 Graphs of the Sine and Cosine Functions
6.5 Graphs of the Tangent, Cotangent, Cosecant, and Secant Functions
6.6 Phase Shift; Building Sinusoidal Models
Chapter Review
Chapter Test
Cumulative Review
Chapter Projects
7. Analytic Trigonometry
7.1 The Inverse Sine, Cosine, and Tangent Functions
7.2 The Inverse Trigonometric Functions (Continued)
7.3 Trigonometric Equations
7.4 Trigonometric Identities
7.5 Sum and Difference Formulas
7.6 Double-angle and Half-angle Formulas
7.7 Product-to-Sum and Sum-to-Product Formulas
Chapter Review
Chapter Test
Cumulative Review
Chapter Projects
8. Applications of Trigonometric Functions
8.1 Right Triangle Trigonometry; Applications
8.2 The Law of Sines
8.3 The Law of Cosines
8.4 Area of a Triangle
8.5 Simple Harmonic Motion; Damped Motion; Combining Waves
Chapter Review
Chapter Test
Cumulative Review
Chapter Projects
9. Polar Coordinates; Vectors
9.1 Polar Coordinates
9.2 Polar Equations and Graphs
9.3 The Complex Plane; DeMoivre's Theorem
9.4 Vectors
9.5 The Dot Product
9.6 Vectors in Space
9.7 The Cross Product
Chapter Review
Chapter Test
Cumulative Review
Chapter Projects
10. Analytic Geometry
10.1 Conics
10.2 The Parabola
10.3 The Ellipse
10.4 The Hyperbola
10.5 Rotation of Axes; General Form of a Conic
10.6 Polar Equations of Conics
10.7 Plane Curves and Parametric Equations
Chapter Review
Chapter Test
Cumulative Review
Chapter Projects
11. Systems of Equations and Inequalities
11.1 Systems of Linear Equations: Substitution and Elimination
11.2 Systems of Linear Equations: Matrices
2. ## Re: Preparing for Calculus
Pretty much everything in the first eight chapters will appear somewhere in a single-variable calculus course. Pay particular attention to trigonometry (chapters 6-8) since calculus involves quite a bit of trig. For example, the unique general solution to the equation $y'' = -ky$where $k > 0$ involves trig functions. Also, chapter 5 will come in very handy.
Material in chapters 9-11 probably won't be seen unless you take multi-variable calculus, linear algebra, differential equations, or any other higher-level math. | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 2, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8786922693252563, "perplexity": 14122.863768542193}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2015-14/segments/1427131298819.92/warc/CC-MAIN-20150323172138-00043-ip-10-168-14-71.ec2.internal.warc.gz"} |
http://mathoverflow.net/questions/79514/what-are-the-smooth-manifolds-in-the-topos-of-sheaves-on-a-smooth-manifold?sort=oldest | # What are the smooth manifolds in the topos of sheaves on a smooth manifold?
The category of internal locales in the Grothendieck topos of sheaves on a locale X is equivalent to the slice category over X. In other words, internal locales over X are precisely morphisms of locales of the form Y→X.
Is the same statement true for smooth manifolds instead of locales and submersions instead of continuous maps?
More precisely, consider the site of smooth manifolds equipped with its standard Grothendieck topology of surjective submersions.
Is the category of internal smooth manifolds in the Grothendieck topos of sheaves on a smooth manifold M equivalent to the category whose objects are surjective submersions of the form N→M and morphisms are commuting triangles?
Definitions tend to branch when we internalize them, so an answer to this question should include the correct definition of a smooth manifold in an arbitrary Grothendieck topos.
According to nLab, internal dualizable modules over the locale of real numbers in the category of sheaves on a smooth manifold M are precisely finite-dimensional vector bundles over M. This can be seen as a further motivation for the above question.
-
@Dmitry: I'm curious why you are thinking about this. What is your motivation? – David Carchedi May 17 '13 at 23:13
@David: I was thinking about smooth analogs of Baez-Dolan cobordism hypothesis. If we assume that the cobordism hypothesis is true in any topos, then one can obtain interesting relationships between differential cohomology and TFTs by applying the cobordism hypothesis to the topos associated to the site of smooth manifolds. – Dmitri Pavlov May 19 '13 at 1:58
## 1 Answer
See the book (a kind of culmination point of the theory: "synthetic differential geometry")
MR1083355 Moerdijk, Ieke; Reyes, Gonzalo E. Models for smooth infinitesimal analysis. Springer-Verlag, New York, 1991.
- | {"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9527830481529236, "perplexity": 199.09844866722415}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": false}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2015-11/segments/1424936463956.95/warc/CC-MAIN-20150226074103-00075-ip-10-28-5-156.ec2.internal.warc.gz"} |
https://www.physicsforums.com/threads/subgroups-stuck-on-a-question.89686/ | Homework Help: Subgroups-Stuck on a question
1. Sep 18, 2005
hgj
Here's the question:
Prove that a nonempty subset H of a group G is a subgroup if for all x and y in H, the element xy^(-1) is also in H.
We have a theorem that says if G is a group and H is a nonempty subset of G, then H is a subgroup of G iff:
(1) H is closed
(2) if h is in H, then the inverse of h in G lies in H.
I know I need to use this theorem, and I have two ideas about how to go about it:
First, I think if I can prove y^(-1) is in H, then the two parts of the theorem follow from that. Unfortunately, I can't figure out how to do this.
My second thought is to prove the two parts separately. If I do this, my proof for closure is:
Assume xy is not in H. Then x is not in H or y is not in H. But this is a contradiction, so xy must be in H. Then closure is satisfied.
After this, though, I get stuck again when I try to prove part (2) about the inverse.
2. Sep 18, 2005
AKG
If for all x and y in H, xy-1 is also in H, then what happens if x = y? Using that, you will have determined the existence of another special element in H. Using that element and the knowledge that xy-1 is in H for every x, y in H, what more can you prove?
For closure, you want to prove that for all x in H, if y is in H then so is xy. If you have proven that (if y is in H then so is y-1) and you use the given fact (if x and y are in H, so is xy-1) then you can prove that xy is in H because it is true so long as:
x(y-1)-1 is in H which is true using the given assumption if
x is in H and y-1 is in H. The first is true by assumption, and the second is true because a) y is in H and b) you should have proved inverses are in H. | {"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9587286710739136, "perplexity": 229.16302406808455}, "config": {"markdown_headings": false, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2018-17/segments/1524125944742.25/warc/CC-MAIN-20180420213743-20180420233743-00612.warc.gz"} |
https://gamedev.stackexchange.com/questions/112142/how-can-i-get-direction-or-link-of-file-in-computer | # How can I get direction or link of file in computer
I want to import an .obj file in my Engine or open some files : To do that I write a link or direction of that file in my computer. Like this
file.open("../Engine/data/model.obj");
But I dont want to write a link every time. In most application if you want to import or open a file you click on import or open and it opens a window where you search that file in your computer and click open.
Here is a picture to see what I am about.
How it is done?. How can i write a c++ program to get link of a file like here?.
Is there any windows libraries or API's to creat something like this.
• The question is also not very clear. What exactly are you trying to do? If you want to present the user with a file choosing dialogue, you should check this out: stackoverflow.com/questions/6145910/… – Lolums Nov 29 '15 at 14:13
You can do the following: (if I understand you correctly)
-E.g get the path of your applications root folder
std::string rootDir = "";
char buffer[MAX_PATH];
GetModuleFileName(NULL, buffer, MAX_PATH);
std::string::size_type pos = std::string(buffer).find_last_of("\\/");
std::string pathstr = std::string(buffer).substr(0,pos);
rootDir = pathstr.c_str(); // e.g = "C:\xx\Desktop\abc"
then use it like:
file.Open(path + "\\data\\Model.obj");
or, so you can do it more simplier for you:
File fileOpen(std::string filePath)
{
return file.Open(path + filePath);
}
EDIT
If you need to know how to make a FileDialog, google it please.. There are soo much sources. | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.4637317359447479, "perplexity": 1833.4976732370872}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 5, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2021-10/segments/1614178357641.32/warc/CC-MAIN-20210226115116-20210226145116-00024.warc.gz"} |
https://rd.springer.com/article/10.1186%2Fs13660-019-1981-2 | # On submultiplicative constants of an algebra
• James S. Cook
• Khang V. Nguyen
Open Access
Research
## Abstract
If $$\mathcal{A}$$ is a finite-dimensional commutative associative real algebra with norm $$\| \cdot\|$$ then we say that the rth submultiplicative constant of $$\mathcal{A}$$ is the smallest constant $$m_{r}(\mathcal{A})$$ for which $$\| x_{1} x_{2} \cdots x_{r} \| \leq m_{r}(\mathcal {A}) \| x_{1} \| \| x_{2} \| \cdots \| x_{r} \|$$. For a product algebra, we show that there exist zero divisors where equality is attained in the inequality defining $$m_{r}( \mathcal{A})$$. We also study $$\rho_{\mathcal{A}} = \limsup_{r \rightarrow\infty} \sqrt[r]{m_{r}(\mathcal{A})}$$. We explain how $$\rho_{\mathcal{A}}$$ appears in the generalization of the Cauchy–Hadamard criterion for hypercomplex power series. We find the submultiplicative constants and $$\rho_{\mathcal{A}}$$ for the real group algebra of the cyclic group of order n as well as the complicated numbers $$\mathcal{C}_{n} = \{ a_{1}+a_{2}k+ \cdots+ a_{n} k^{n-1} | a_{i} \in\mathbb{R}, k^{n} = -1 \}$$ with Euclidean norm. Submultiplicative constants for the n-dual numbers $$\Delta_{n}$$ with Euclidean norm are also calculated or conjectured for $$n \leq6$$. We show, for $$n \geq2$$, $$\rho_{\Delta_{n}} = 1$$ for $$\Delta_{n}$$ given the p-norm.
## Keywords
Cyclic group algebra Complicated numbers Hypercomplex analysis Submultiplicative norms
## 1 Introduction
Suppose $$V_{1}, \dots, V_{r}$$ are finite-dimensional spaces over either $$\mathbb {R}$$ or $$\mathbb {C}$$, and X is a normed space. It is known that any bounded multilinear map $$T: V_{1} \times V_{2} \times\cdots\times V_{r} \rightarrow X$$ is continuous. Furthermore, finite-dimensional $$V_{1}, \dots, V_{r}$$ have compact unit ball whose Cartesian products are likewise compact. Therefore, the extreme value theorem yields that the norm $$\lVert T \rVert_{\mathrm{op}} = \sup\{ \lVert T(v_{1}, v_{2}, \ldots, v_{r}) \rVert : \lVert v_{i} \rVert \le1, 1 \le i \le r \}$$ is attained by evaluation of T at some point in the Cartesian product of the unit-balls of $$V_{1}, \dots, V_{r}$$. Since r-fold multiplication on an algebra $$\mathcal {A}$$ provides an $$\mathcal {A}$$-valued r-linear map over $$\mathcal {A}$$, we have the following result:
### Theorem 1.1
If$$\mathcal {A}$$is a finite-dimensional unital associative algebra (with multiplication denoted as ⋆) over$$\mathbb{R}$$or$$\mathbb{C}$$with a norm$$\lVert\cdot \rVert$$then there exists a smallest constant$$m_{r}(\mathcal {A}) \in\mathbb{R}$$for each$$r \in\mathbb{N}, r \le2$$such that$$\lVert x_{1} \star x_{2} \star\cdots\star x_{r} \rVert \le m_{r}(\mathcal {A}) \lVert x_{1} \rVert \lVert x_{2} \rVert \cdots \lVert x_{r} \rVert$$for all$$x_{1}, x_{2}, \ldots, x_{r} \in \mathcal {A}$$. Furthermore, there exist$$y_{1},\dots, y_{r} \in \mathcal {A}$$for which equality is attained; $$\lVert y_{1} \star y_{2} \star\cdots\star y_{r} \rVert = m_{r}(\mathcal {A}) \lVert y_{1} \rVert \lVert y_{2} \rVert \cdots \lVert y_{r} \rVert$$.
We call $$m_{r}(\mathcal {A})$$ the rth submultiplicative constant of $$\mathcal {A}$$ (with respect to the norm $$\lVert\cdot \rVert$$). Usually, we denote $$m_{2}(\mathcal {A}) = m_{\mathcal {A}}$$ and name it the submultiplicative constant. This improves the less sharp use of $$m_{\mathcal {A}}$$ in [1].
### Proposition 1.2
If$$m_{\mathcal {A}}$$is the submultiplicative constant for$$\mathcal {A}$$then$$m_{r}(\mathcal {A}) \leq m_{\mathcal {A}}^{r-1}$$. Also, if there exists$$x \in \mathcal {A}$$for which$$\| x^{r} \| = m_{\mathcal {A}}^{r-1} \| x\|^{r}$$for each$$r \in \mathbb {N}$$then$$m_{r}(\mathcal {A}) = m_{\mathcal {A}}^{r-1}$$.
### Proof
If $$\| x \star y \| \leq m_{\mathcal {A}}\| x \| \| y \|$$ for all $$x,y \in \mathcal {A}$$ then by repeated application of the inequality for the norm of the product of $$x_{1},x_{2}, \dots, x_{r}$$ we find
$$\Vert x_{1} \star x_{2} \star\cdots\star x_{r} \Vert \leq m_{\mathcal {A}}^{r-1} \Vert x_{1} \Vert \Vert x_{2} \Vert \cdots \Vert x_{r} \Vert .$$
(1)
Therefore, $$m_{r}(\mathcal {A}) \leq m_{\mathcal {A}}^{r-1}$$. Suppose there exists $$x \in \mathcal {A}$$ for which $$\| x^{r} \| = m_{\mathcal {A}}^{r-1} \| x \|^{r}$$. Setting $$x_{1} = x_{2} = \cdots= x_{r} = x$$ shows (1) is sharp, hence $$m_{r}(\mathcal {A}) = m_{\mathcal {A}}^{r-1}$$. □
From these constants, we denote another constant related to the normed algebra $$\mathcal {A}$$
$$\rho_{\mathcal {A}}= \limsup_{r \rightarrow\infty} \sqrt[r]{ m_{r}( \mathcal {A}) }.$$
(2)
Observe that $$\rho_{\mathcal {A}}$$ exists since $$m_{r}(\mathcal {A}) \leq m_{\mathcal {A}}^{r - 1}$$, so $$\rho_{\mathcal {A}}\leq m_{\mathcal {A}}$$. In another direction, substitute $$x_{1} = x_{2} = \cdots= x_{r} = 1$$ to obtain $$\lVert1^{r} \rVert \le m_{r}(\mathcal {A}) \lVert1 \rVert^{r}$$, which implies $$m_{r}(\mathcal {A}) \ge \lVert1 \rVert^{-(r - 1)}$$ and
$$\lVert1 \rVert^{-1} \leq\rho_{\mathcal {A}}\leq m_{\mathcal {A}}.$$
(3)
For a finite-dimensional associative real algebra $$\mathcal {A}$$, the radius of convergence for the geometric series $$1+z+z^{2}+ \cdots$$ is shown to be at least $$1/m_{\mathcal {A}}$$ in Theorem 4.5 of [2]. We offer an improved radius in what follows:
### Theorem 1.3
If$$\sum_{n = 0}^{\infty}{c_{n} (z - z_{0})^{n}}$$has$$0< C = \limsup_{n \rightarrow\infty} \sqrt[n]{ \lVert c_{n} \rVert} < \infty$$then the power series converges absolutely for$$z \in \mathcal {A}$$such that$$\lVert z - z_{0} \rVert < (C \rho_{A})^{-1}$$.
### Proof
For $$C = \limsup_{n \rightarrow\infty} \sqrt[n]{ \lVert c_{n} \rVert}$$ and $$\lVert z - z_{0} \rVert < (C \rho_{A})^{-1}$$ observe
$$\limsup_{n \rightarrow\infty} \sqrt[n]{ \bigl\lVert c_{n} (z - z_{0})^{n} \bigr\rVert } \le\limsup_{n \rightarrow\infty} \sqrt[n]{m_{n}(\mathcal {A}) \lVert c_{n} \rVert \lVert z - z_{0} \rVert^{n}} = \rho_{A} C \lVert z-z_{0} \rVert < 1.$$
(4)
Thus $$\limsup_{n \rightarrow\infty} \sqrt[n]{ \lVert c_{n} (z - z_{0})^{n} \rVert} < 1$$, and we find $$\sum_{n = 0}^{\infty}{c_{n} (z - z_{0})^{n}}$$ converges absolutely by applying the Root Test for a series over an algebra (Theorem 4.2 of [2]). □
The theorem above shows that convergence of a power series $$\sum c_{n} (z-z_{o})^{n}$$ over an algebra $$\mathcal {A}$$ is governed both by the usual Cauchy–Hadamard criterion involving $$\limsup_{n \rightarrow\infty} \sqrt[n]{\| c_{n} \|}$$ and the constant $$\rho_{\mathcal {A}}$$. We note $$\rho _{\mathcal {A}}$$ depends on both $$\mathcal {A}$$ and the norm which $$\mathcal {A}$$ is given. In the remaining sections of this paper, we endeavor to calculate both $$m_{r}(\mathcal {A})$$ and $$\rho_{\mathcal {A}}$$ for several interesting algebras.
## 2 Transfer principle
### Theorem 2.1
(Transfer Principle)
If$$\mathcal {A}, \mathcal {B}$$are finite-dimensional, unital, associative, normed algebras over$$\mathbb {R}$$or$$\mathbb {C}$$for which there exists an algebra isomorphism$$\varphi: \mathcal {A}\rightarrow \mathcal {B}$$which is also a dilation (meaning there exists a constant$$\nu> 0$$so that$$\lVert\varphi(x) \rVert = \nu \lVert x \rVert$$for all$$x \in \mathcal {A}$$). Then, for$$r \ge2$$, $$\nu^{r - 1} \cdot m_{r}(\mathcal {B}) = m_{r}(\mathcal {A})$$and$$\rho _{\mathcal {A}}= \nu\cdot\rho_{\mathcal {B}}$$.
### Proof
Observe $$\lVert\varphi(x_{1} \cdots x_{r}) \rVert = \lVert\varphi(x_{1}) \cdots\varphi(x_{r}) \rVert \le m_{r}(\mathcal {B}) \lVert\varphi(x_{1}) \rVert \cdots \lVert\varphi(x_{r}) \rVert$$. Then as φ is a dilation with constant ν, it follows $$\| x_{1} \cdots x_{r} \| \leq m_{r}(\mathcal {B}) \nu ^{r-1} \lVert x_{1} \rVert \cdots \lVert x_{r} \rVert$$. Recall $$m_{r}(\mathcal {A})$$ is the smallest constant for which $$\| x_{1} \cdots x_{r} \| \leq m_{r}(\mathcal {A}) \lVert x_{1} \rVert \cdots \lVert x_{r} \rVert$$ for all $$x_{1}, \dots, x_{r} \in \mathcal {A}$$. Therefore, $$m_{r}(\mathcal {A}) \leq m_{r}(\mathcal {B}) \nu^{r-1}$$. Observe $$\varphi^{-1}: \mathcal {B}\rightarrow \mathcal {A}$$ is a dilation with constant $$\frac{1}{\nu}$$ hence $$m_{r}(\mathcal {B}) \leq m_{r}(\mathcal {A}) \frac{1}{\nu ^{r-1}}$$, from which we find $$m_{r}(\mathcal {A}) \geq\nu^{r-1}m_{r}(\mathcal {B})$$. Hence $$\nu^{r-1}m_{r}(\mathcal {B}) = m_{r}(\mathcal {A})$$ and thus $$\rho_{\mathcal {A}}= \limsup_{r \rightarrow\infty} \sqrt[r]{ \nu^{r-1}m_{r}(\mathcal {B})} = \nu\limsup_{r \rightarrow\infty} \sqrt[r]{m_{r}(\mathcal {B})} = \nu\rho _{\mathcal {B}}$$. □
### Theorem 2.2
(Product Algebra with Weighted p-norm)
Let$$\mathcal {A}_{1}, \dots, \mathcal {A}_{s}$$, be finite- dimensional associative normed algebras withrth submultiplicative constant$$m_{i,r}$$for$$r\geq2$$and with$$\rho_{i} = \limsup_{r \rightarrow\infty} \sqrt [r]{m_{i,r}}$$for$$1 \leq i \leq s$$. If$$\mathcal {A}= \mathcal {A}_{1} \times \mathcal {A}_{2} \times\cdots\times \mathcal {A}_{s}$$then define weightedp-norm with weights$$a_{1},\dots, a_{s} >0$$by$$\lVert(x_{1}, x_{2}, \ldots, x_{s}) \rVert = \max_{1 \le i \le s} {a_{i} \lVert x_{i} \rVert}$$for$$p = \infty$$and
$$\bigl\lVert (x_{1}, x_{2}, \ldots, x_{s}) \bigr\rVert = \Biggl( \sum_{i = 1}^{s} a_{i}^{p} \lVert x_{i} \rVert^{p} \Biggr)^{\frac{1}{p}}$$
for$$p< \infty$$. Then$$\mathcal {A}$$with the weightedp-norm defines a normed associative algebra with$$m_{r}(\mathcal {A}) = \max_{1 \le i \le s} \{ m_{i,r}/a_{i}^{r - 1} \}$$and$$\rho_{\mathcal {A}}= \max_{1 \le i \le s} \frac{\rho_{i}}{a_{i}}$$.
### Proof
Given $$x_{i, j} \in A_{i}$$ for $$1 \leq i \leq s, 1 \leq j \leq r$$. Let $$\mu_{r} = m_{r}(\mathcal {A}) = \max_{1 \le i \le s} \{ m_{i,r}/a_{i}^{r - 1} \}$$. Then
\begin{aligned} \mu_{r}^{p} \prod_{j = 1}^{r} \bigl\lVert (x_{1, j}, \ldots, x_{s, j}) \bigr\rVert ^{p} & = \mu_{r}^{p} \prod_{j = 1}^{r} \sum_{i = 1}^{s} a_{i}^{p} \lVert x_{i, j} \rVert^{p} \\ & \ge\mu_{r}^{p} \sum_{i = 1}^{s} \prod_{j = 1}^{r} a_{i}^{p} \lVert x_{i, j} \rVert^{p} \\ &= \mu_{r}^{p} \sum_{i = 1}^{s} \bigl(a_{i}^{p}\bigr)^{r} \Biggl( \prod _{j = 1}^{r} \lVert x_{i, j} \rVert \Biggr)^{p} \\ & \ge\max_{1 \le i \le s} \biggl\{ \frac{m_{i,r}^{p}}{a_{i}^{(r - 1)p}} \biggr\} \sum_{i = 1}^{s} \bigl(a_{i}^{p} \bigr)^{r} \Biggl( \frac{1}{m_{i, r}} \Biggl\lVert \prod _{j = 1}^{r} x_{i, j} \Biggr\rVert \Biggr)^{p} \\ & \ge\sum_{i = 1}^{s} \frac{m_{i,r}^{p}}{a_{i}^{(r - 1) p}} \cdot a_{i}^{rp} \cdot\frac{1}{m_{i, r}^{p}} \Biggl\lVert \prod_{j = 1}^{r} x_{i, j} \Biggr\rVert ^{p} \\ &= \sum_{i = 1}^{s} a_{i}^{p} \Biggl\lVert \prod_{j = 1}^{r} x_{i, j} \Biggr\rVert ^{p} \\ & = \Biggl\lVert \prod_{j = 1}^{r} ( x_{1, j}, \ldots, x_{s, j} ) \Biggr\rVert ^{p}. \end{aligned}
(5)
From the above we derive
$$\mu_{r} \prod_{j = 1}^{r} \bigl\lVert (x_{1, j}, \ldots, x_{s, j}) \bigr\rVert \geq \Biggl\lVert \prod_{j = 1}^{r} ( x_{1, j}, \ldots, x_{s, j} ) \Biggr\rVert .$$
(6)
Let k be an index between 1 and s such that $$\frac {m_{k,r}}{a_{k}^{r - 1}} = \mu_{r}$$ and, following the last sentence in Theorem 1.1, let $$y_{k, j} \in \mathcal {A}_{k}$$ ($$1 \le j \le r$$) be such that $$m_{k, r} \prod_{j = 1}^{r} \lVert y_{k, j} \rVert = \lVert\prod_{j = 1}^{r} y_{k, j} \rVert$$. Let $$e_{k} \in \mathcal {A}$$ denote $$(0,\dots, 1, \dots, 0)$$ where 1 is in the kth entry. Then calculate
\begin{aligned} \mu_{r}^{p} \prod_{j = 1}^{r} \lVert y_{k, j} e_{k} \rVert^{p} &= \Biggl( a_{k} m_{k,r} \prod_{j = 1}^{r} \lVert y_{k, j} \rVert \Biggr)^{p} \\ &= \Biggl( a_{k} \Biggl\lVert \prod _{j = 1}^{r} y_{k, j} \Biggr\rVert \Biggr)^{p} \\ &= \Biggl\lVert \prod_{j = 1}^{r} (y_{k, j} e_{k}) \Biggr\rVert ^{p}, \end{aligned}
(7)
which indicates (6) is sharp, as equality is attained by setting $$(x_{1, j}, \ldots, x_{s, j}) = y_{k, j} e_{k}$$ for $$j=1,\dots, r$$. Thus $$m_{r}(\mathcal {A}) = \max_{1 \le i \le s} \{ m_{i,r}/a_{i}^{r - 1} \}$$. Finally, observe
\begin{aligned} \rho_{\mathcal {A}} &= \limsup_{r \rightarrow\infty} \sqrt[r]{ \max _{1 \le i \le s} \bigl\{ m_{i,r}/a_{i}^{r - 1} \bigr\} } \\ &= \limsup_{r \rightarrow\infty} \max_{1 \le i \le s} \biggl\{ \frac{\sqrt[r]{m_{i,r}}}{\sqrt[r]{a_{i}^{r - 1}}} \biggr\} \\ &= \max_{1 \le i \le s} \biggl\{ \limsup_{r \rightarrow\infty} \frac{\sqrt[r]{m_{i,r}}}{\sqrt[r]{a_{i}^{r - 1}}} \biggr\} \\ &= \max_{1 \le i \le s} \biggl\{ \frac{\rho_{i}}{a_{i}} \biggr\} . \end{aligned}
(8)
□
### Remark 2.3
If $$\varphi: \mathcal {B}\rightarrow \mathcal {A}= \mathcal {A}_{1} \times\cdots\times \mathcal {A}_{s}$$ is an isomorphism which is also a dilation then the proof given suggests a calculational method for finding an element $$x \in \mathcal {B}$$ for which $$\| x^{2} \| = m_{\mathcal {B}} \| x \|^{2}$$. In particular, select the element $$y_{k, j} e_{k}$$ for $$r=2$$ as in the proof and set $$x=\varphi^{-1}(y_{k, j} e_{k})$$. In this construction we will find that x is a zero-divisor. However, if we consider algebras which are not product algebras then the situation is different. For example, in Theorem 5.1(1) we find that the unit $$x = \sqrt {2}+\varepsilon$$ gives $$\| x \| = m_{\mathcal {A}}\| x\|^{2}$$.
## 3 Submultiplicative constants for cyclic group algebra
The n-hyperbolic numbers are the algebra $$\mathcal {H}_{n} = \mathbb{R}[x] / \langle x^{n} - 1 \rangle$$ which is usually represented as
$$\mathcal {H}_{n} = \bigl\{ a_{0} + a_{1} j + \cdots+ a_{n - 1} j^{n - 1} | a_{i} \in \mathbb{R} \bigr\} ,$$
where we identify j with $$x + \langle x^{n} - 1 \rangle$$ and 1 with $$1 + \langle x^{n} - 1 \rangle$$. One may note that $$\mathcal {H}_{n}$$ is the real group algebra of the cyclic group of order n. In this section we derive the submultiplicative constants for hyperbolic numbers provided that $$\mathcal {H}_{n}$$ is given the norm
$$\bigl\Vert a_{0} + a_{1} j + \cdots+ a_{n - 1} j^{n - 1} \bigr\Vert = \sqrt{a_{0}^{2} + a_{1}^{2} + \cdots+ a_{n - 1}^{2}}.$$
### 3.1 $$\mathcal {H}_{n}$$ for even n
Notice that if $$n=2m$$ then we have the following factorization of $$x^{n}-1$$:
$$x^{n}-1 = (x - 1) (x + 1) \prod_{k = 1}^{m - 1} \bigl( x - e^{i \frac{k \pi}{m}} \bigr) \bigl( x - e^{-i \frac{k \pi}{m}} \bigr).$$
(9)
The Chinese remainder theorem and the factorization above suggests we form the isomorphism $$\varphi: \mathcal {H}_{2m} \rightarrow\mathbb{R}^{2} \times\mathbb{C}^{m - 1}$$ we describe next. If $$p(j) = a_{0}+ a_{1}j + \cdots+a_{n}j^{n-1} \in \mathcal {H}_{n}$$ then $$p(c) = a_{0}+a_{1}c+ \cdots+ a_{n} c^{n-1}$$ for $$c \in \mathbb {C}$$, thus for $$p(j) \in \mathcal {H}_{n}$$ define
$$\varphi\bigl(p(j)\bigr) = \bigl(p(1),p(-1),p\bigl(e^{i\pi/m} \bigr),p\bigl(e^{2i\pi/m}\bigr), \dots, p\bigl(e^{(m-1)i\pi/m}\bigr)\bigr).$$
(10)
Observe $$\varphi: \mathcal {H}_{n} \rightarrow \mathbb {R} \times \mathbb {R} \times \mathbb {C} ^{m-1}$$ is an isomorphism of real associative algebras. Our goal is to use Theorem 2.1 by assigning $$\mathcal{B} = \mathbb {R} \times \mathbb {R} \times \mathbb {C} ^{m-1}$$ the appropriate weighted norm as to make (10) a dilation. After some experimentation, one finds that
$$\bigl\lVert (a, b, z_{1}, z_{2}, \ldots, z_{m - 1}) \bigr\rVert = \sqrt {a^{2} + b^{2} + 2 \bigl( \vert z_{1} \vert ^{2} + \cdots+ \vert z_{m - 1} \vert ^{2} \bigr)}$$
(11)
serves our purpose. Considering $$p(j) = \sum_{k = 0}^{2m - 1} a_{k} j^{k}$$,
\begin{aligned} \bigl\lVert \varphi \bigl( p(j) \bigr) \bigr\rVert ^{2} ={}& \Biggl( \sum_{k = 0}^{2m - 1} a_{k} \Biggr)^{2} + \Biggl( \sum_{k = 0}^{2m - 1} (-1)^{k} a_{k} \Biggr)^{2} + 2 \sum _{s = 1}^{m - 1} \Biggl\vert \sum _{k = 0}^{2m - 1} a_{k} e^{\frac {iks\pi}{m}} \Biggr\vert ^{2} \\ ={}& 2 \sum_{k = 0}^{2m - 1} a_{k}^{2} + 2 \sum_{p < q} a_{p} a_{q} \bigl( 1 + (-1)^{p + q} \bigr) \\ & + 2 \sum_{s = 1}^{m - 1} \Biggl[ \Biggl( \sum_{k = 0}^{2m - 1} a_{k} \cos \biggl( \frac{ks \pi}{m} \biggr) \Biggr)^{2} + \Biggl( \sum _{k = 0}^{2m - 1} a_{k} \sin \biggl( \frac{ks \pi}{m} \biggr) \Biggr)^{2} \Biggr] \\ ={}& 2m \sum_{k = 0}^{2m - 1} a_{k}^{2} + 2 \sum_{p < q} a_{p} a_{q} \bigl( 1 + (-1)^{p + q} \bigr) \\ &{} + 4 \sum_{s = 1}^{m - 1} \sum _{p < q} a_{p} a_{q} \biggl[ \cos \biggl( \frac{ps \pi}{m} \biggr) \cos \biggl( \frac{qs \pi}{m} \biggr) + \sin \biggl( \frac{ps \pi}{m} \biggr) \sin \biggl( \frac {qs \pi}{m} \biggr) \biggr] \\ ={}& 2m \bigl\Vert p(j) \bigr\Vert ^{2} + 2 \sum _{p < q} a_{p} a_{q} \Biggl[ 1 + (-1)^{p + q} + 2 \sum_{s = 1}^{m - 1} \cos \biggl( \frac{(p - q)s\pi}{m} \biggr) \Biggr] \\ ={}& 2m \bigl\Vert p(j) \bigr\Vert ^{2} + 2 \sum _{p < q} a_{p} a_{q} \sum _{s = 0}^{2m - 1} \cos \biggl(\frac{(p - q)s\pi}{m} \biggr). \end{aligned}
(12)
### Lemma 3.1
If$$p,q,m$$are integers and$$p< q$$then$$\sum_{s = 0}^{2m - 1} \cos (\frac{(p - q)s\pi}{m} )=0$$.
### Proof
If $$p-q$$ is not a multiple of m then let $$\theta= \pi/m$$ and note the points $$1,e^{i\theta},\dots, e^{i(2m-1)\theta}$$ form a set of 2m-symmetrically arranged points on the unit circle whose centroid is the origin. Since $$e^{i\theta}=\cos\theta+i\sin\theta$$, we identify $$\frac{1}{n}\sum_{s = 0}^{2m - 1} \cos (\frac{(p - q)s\pi}{m} )$$ as the real coordinate of the centroid. If $$p-q$$ is a multiple of m then $$\cos (\frac{(p - q)s\pi}{m} ) = (-1)^{s}$$ and the lemma follows. □
In view of Lemma 3.1 and (12), we find $$\lVert\varphi( z) \rVert^{2} = 2m \| z \|^{2}$$ for each $$z \in \mathcal {H}_{n}$$. Thus φ is a dilation with constant $$\nu= \sqrt{2m}$$. Let $$\mathcal{B} = \mathbb {R} ^{2} \times \mathbb {C} ^{m-1}$$ have norm as in (11). Then Theorem 2.2 indicates the submultiplicative constant of $$\mathcal{B}$$ is $$m_{\mathcal{B}}=1$$. Therefore, Theorem 2.1 provides $$m_{\mathcal {H}_{n}} = \nu m_{\mathcal{B}}$$, thus $$m_{\mathcal {H}_{n}} = \sqrt{2m} = \sqrt{n}$$.
### 3.2 $$\mathcal {H}_{n}$$ for odd n
Notice that if $$n=2m+1$$ then we have the following factorization of $$x^{n}-1$$:
$$x^{n}-1 = (x - 1)\prod_{k = 1}^{m} \bigl( x - e^{\frac{2\pi k i}{2m+1}} \bigr) \bigl( x - e^{-\frac{2\pi k i}{2m+1}} \bigr).$$
(13)
As in (10) we define an isomorphism $$\varphi: \mathcal {H}_{2m+1} \rightarrow \mathbb {R} \times \mathbb {C} ^{m}$$ for each $$p(j) \in \mathcal {H}_{2m+1}$$ by
$$\varphi\bigl(p(j)\bigr) = \bigl( p(1), p \bigl( e^{\frac{ 2 \pi i}{2m + 1}} \bigr), p \bigl( e^{\frac{ 4 \pi i}{2m + 1}} \bigr), \ldots, p \bigl( e^{ \frac{2m \pi i }{2m + 1}} \bigr) \bigr).$$
(14)
Let $$\mathcal{B} = \mathbb {R} \times \mathbb {C} ^{m}$$ have norm
$$\bigl\lVert (a, z_{1}, \ldots, z_{m}) \bigr\rVert = \sqrt{a^{2} + 2 \bigl( \vert z_{1} \vert ^{2} + \cdots+ \vert z_{m} \vert ^{2} \bigr)}.$$
(15)
Thus for $$p(j) = \sum_{k=0}^{2m}a_{k} j^{k}$$,
\begin{aligned} \bigl\lVert \varphi \bigl( p(j) \bigr) \bigr\rVert ^{2} ={} &\Biggl( \sum_{k = 0}^{2m} a_{k} \Biggr)^{2} + 2 \sum_{s = 1}^{m} \Biggl\vert \sum_{k = 0}^{2m} a_{k} e^{i\frac{i2k s\pi}{2m + 1}} \Biggr\vert ^{2} \\ ={}& \sum_{k = 0}^{2m} a_{k}^{2} + 2 \sum_{p < q} a_{p} a_{q}\\ &{}+ 2 \sum_{s = 1}^{m} \Biggl[ \Biggl( \sum_{k = 0}^{2m} a_{k} \cos \biggl( \frac{2ks \pi}{2m + 1} \biggr) \Biggr)^{2} + \Biggl( \sum_{k = 0}^{2m} a_{k} \sin \biggl( \frac{2ks \pi}{2m + 1} \biggr) \Biggr)^{2} \Biggr] \\ ={}& (2m + 1) \sum_{k = 0}^{2m} a_{k}^{2} + 2 \sum_{p < q} a_{p} a_{q} \\ &{} + 4 \sum_{s = 1}^{m} \sum _{p < q} a_{p} a_{q} \biggl[ \cos \biggl( \frac{ 2sp \pi}{2m + 1} \biggr) \cos \biggl( \frac{2sq \pi}{2m + 1} \biggr)\\ &{} + \sin \biggl( \frac{2sp \pi}{2m + 1} \biggr) \sin \biggl( \frac{2sq \pi}{2m + 1} \biggr) \biggr] \\ ={}& (2m + 1) \bigl\Vert p(j) \bigr\Vert ^{2} + 2 \sum _{p < q } a_{p} a_{q} \Biggl[1 + 2 \sum_{s = 1}^{m} \cos \biggl( \frac{2s(p - q) \pi}{2m + 1} \biggr) \Biggr] \\ ={}& (2m + 1) \bigl\Vert p(j) \bigr\Vert ^{2} + 2 \sum _{p < q} a_{p} a_{q} \sum _{s = 0}^{2m} \cos \biggl( \frac{2s(p - q) \pi}{2m + 1} \biggr). \end{aligned}
(16)
The proof of Lemma 3.1 is easily adapted to show the following result:
### Lemma 3.2
If$$p,q,m$$are integers and$$p< q$$then$$\sum_{s = 0}^{2m} \cos (\frac{2s(p - q)\pi}{2m+1} )=0$$.
In view of the Lemma 3.2 and (16), we find $$\lVert\varphi( z) \rVert^{2} = (2m+1) \| z \|^{2}$$ for each $$z \in \mathcal {H}_{n}$$ where $$n=2m+1$$. Thus φ is a dilation with constant $$\nu= \sqrt{2m+1}$$. Let $$\mathcal{B} = \mathbb {R} \times \mathbb {C} ^{m}$$ have norm as in (15). Then Theorem 2.2 indicates that the submultiplicative constant of $$\mathcal{B}$$ is $$m_{\mathcal {B}}=1$$. Therefore, Theorem 2.1 provides $$m_{\mathcal {H}_{n}} = \nu m_{\mathcal{B}}$$ and thus $$m_{\mathcal {H}_{n}} = \sqrt{2m+1} = \sqrt{n}$$.
### Theorem 3.3
If$$\mathcal {H}_{n}$$is given norm$$\| a_{0}+a_{1}j+ \cdots +a_{n}j^{n-1} \| = \sqrt{ a_{0}^{2}+a_{2}^{2}+ \cdots +a_{n}^{2}}$$then$$m_{\mathcal {H}_{n}} = \sqrt{n}$$. Moreover, for$$r \geq2$$we find$$m_{r}( \mathcal {H}_{n}) = n^{(r-1)/2}$$and$$\rho_{\mathcal {H}_{n}} = \sqrt{n}$$.
### Proof
We have already proved $$m_{\mathcal {H}_{n}} = \sqrt{n}$$. Consider $$x = 1+j+j^{2}+ \cdots+ j^{n-1}$$ and observe $$x^{2}=nx$$, hence $$x^{r} = n^{r-1}x$$ for $$r \in \mathbb {N}$$. Moreover, $$\| x\| = \sqrt{n}$$, thus $$\| x^{r} \| = m_{\mathcal {H}_{n}}^{r-1} \| x \|^{r}$$ and Proposition 1.2 provides $$m_{r}(\mathcal {H}_{n}) = n^{(r-1)/2}$$. Finally, calculate
$$\rho_{\mathcal {H}_{n}} = \limsup_{r \rightarrow\infty} \sqrt[r]{ m_{r}( \mathcal {H}_{n}) } = \limsup_{r \rightarrow\infty} \sqrt[r]{ n^{(r-1)/2} } = \sqrt{n}.$$
(17)
□
It is interesting to note that the inequality $$\| xy \| \leq\sqrt{n} \| x\| \| y \|$$ is sharp for $$x=y = 1+j+j^{2}+ \cdots+ j^{n-1}$$ since $$\| x \| = \sqrt{n}$$ and as
$$x^{2} = \bigl(1+j+j^{2}+ \cdots+ j^{n-1} \bigr)^{2} = n\bigl(1+j+j^{2}+ \cdots+ j^{n-1}\bigr) = nx.$$
(18)
Thus $$\| xy \| = n \| x \| = n \sqrt{n} = \sqrt{n} \| x\| \| y\|$$. The same x has $$x(x-n)=0$$, which shows x and $$x-n$$ are zero-divisors. This illustrates Remark 2.3.
## 4 Submultiplicative constant of the complicated numbers
We follow [3] and say $$\mathcal{C}_{n} = \{ a_{0}+a_{1}k+ \cdots +a_{n-1}k^{n-1} | a_{i} \in \mathbb {R} , k^{n}=-1 \}$$ is the set of complicated numbers. Let us assume the norm on $$\mathcal{C}_{n}$$ is given by
$$\bigl\Vert a_{0}+a_{1}k+ \cdots+a_{n-1}k^{n-1} \bigr\Vert = \sqrt{a_{0}^{2}+ \cdots+a_{n-1}^{2}}$$
(19)
throughout this section.
### Theorem 4.1
The submultiplicative constant
$$m_{\mathcal{C}_{n}} = \textstyle\begin{cases} \sqrt{n/2} & \textit{if }n\textit{ is even,} \\ \sqrt{n} & \textit{if}n\textit{ is odd.} \end{cases}$$
### Proof
If n is odd then $$\varPsi(k) = -j$$ defines an isomorphism of $$\mathcal {C}_{n}$$ and $$\mathcal{H}_{n}$$ since $$\varPsi(k)^{n} = (-j)^{n} = (-1)^{n}j^{n}=-1$$. Extending Ψ to arbitrary elements,
$$\varPsi \bigl( a_{0}+a_{1}k+ \cdots+a_{n-1}k^{n-1} \bigr) = a_{0}-a_{1}j+a_{2}j^{2}+ \cdots+a_{n-1}j^{n-1}.$$
If $$\| a_{0}+a_{1}k+ \cdots+a_{n-1}k^{n-1} \| = \sqrt{a_{0}^{2}+ \cdots +a_{n-1}^{2}}$$ then using the norm before discussed for $$\mathcal{H}_{n}$$ observe $$\| \varPsi(z) \| = \| z \|$$. Therefore, from Theorem 2.1 we find $$m_{\mathcal{C}_{n}} = m_{\mathcal{H}_{n}}$$.
Consider $$\mathcal{C}_{n}$$ for $$n=2m$$ with $$m \geq1$$. Let $$\theta_{j} = \frac{\pi}{n}(2j+1)$$ and $$x_{j} = \exp ( i\theta_{j} )$$ for $$j=0,1, \dots, n/2-1$$. Define $$\varphi: \mathcal{C}_{n} \rightarrow \mathbb {C} ^{n/2}$$ by
$$\varphi\bigl( f(k)\bigr) = \bigl(f(x_{0}), \dots, f(x_{n/2-1}) \bigr).$$
(20)
If $$f(k) = a_{0}+a_{1}k+ \cdots+ a_{n-1}k^{n-1} \in\mathcal{C}_{n}$$ then calculate
\begin{aligned} \bigl\vert f(x_{j}) \bigr\vert ^{2} &= \Biggl\vert \sum_{q=1}^{n-1} a_{q}\exp ( iq\theta_{j} ) \Biggr\vert ^{2} \\ &= \Biggl\vert \sum_{q=1}^{n-1} a_{q} \bigl[ \cos ( q\theta_{j} )+i\sin ( q \theta_{j} ) \bigr] \Biggr\vert ^{2} \\ & = \Biggl[ \sum_{q=1}^{n-1} a_{q} \cos ( q\theta_{j} ) \Biggr]^{2}+ \Biggl[ \sum_{q=1}^{n-1} a_{q}\sin ( q \theta_{j} ) \Biggr]^{2} \\ & = \sum_{q=1}^{n-1} a_{q}^{2}+ \sum_{p< q} a_{p}a_{q} \bigl[\cos ( p\theta_{j} )\cos ( q \theta_{j} )+\sin ( p\theta_{j} )\sin ( q\theta_{j} ) \bigr] \\ & = \bigl\Vert f(k) \bigr\Vert ^{2}+ \sum _{p< q} a_{p}a_{q} \cos \bigl( (p-q) \theta_{j} \bigr). \end{aligned}
(21)
Observe that, much for the same reasons as given for Lemma 3.1,
$$\sum_{j=0}^{n/2-1}\cos \bigl( (p-q)\theta_{j} \bigr) = \sum_{j=0}^{n/2-1} \cos \biggl( \frac{\pi(p-q)(2j+1)}{2m} \biggr)=0.$$
(22)
If $$\mathbb {C} ^{n/2}$$ has norm $$\| (z_{1}, \dots, z_{n/2}) \|^{2} = |z_{1}|^{2}+ \cdots+ |z_{n/2}|^{2}$$ then Theorem 2.2 indicates $$m_{ \mathbb {C} ^{n/2}}=1$$. Notice (21) and (22) yield
$$\bigl\Vert \varphi\bigl( f(k)\bigr) \bigr\Vert ^{2} = \sum _{j=0}^{n/2-1} \bigl\vert f(x_{j}) \bigr\vert ^{2} = \frac {n}{2} \bigl\Vert f(k) \bigr\Vert ^{2}.$$
(23)
Consequently, φ is a dilation with $$\nu= \sqrt{n/2}$$, and Theorem 2.1 provides $$m_{\mathcal{C}_{n}} = \sqrt{n/2}$$. □
In the special case $$n=2$$, we note $$\mathcal{C}_{2}$$ has a multiplicative norm. However, for other $$n >2$$ the norm is not multiplicative. Furthermore, $$\| xy \| = m_{\mathcal{C}_{n}} \| x \| \| y \|$$ only for select $$x,y$$. In particular, if n is odd then $$x = 1-k+k^{2}-\cdots+k^{n-1} \in\mathcal{C}_{n}$$ has $$x^{2} = nx$$, thus $$\| x^{2} \| = \sqrt{n} \| x \|^{2}$$. In contrast, for even $$n \neq2$$ notice $$x = \sum_{j=0}^{n-1}\cos ( \frac{j \pi}{n} ) k^{j}$$ is a nonzero zero-divisor with $$x^{2} = \frac{n}{2}x$$ and $$\| x \| = \sqrt {\frac{n}{2}}$$. Thus $$\| x^{2} \| = \sqrt{\frac{n}{2}} \| x \|^{2}$$. Once again, Remark 2.3 is illustrated.
## 5 Submultiplicative constant of the dual numbers
The n-dual number is defined as an element of $$\Delta_{n} = \mathbb {R}[x] / \langle x^{n} \rangle$$, or equivalently, $$a_{0} + a_{1} \varepsilon + \cdots+ a_{n - 1} \varepsilon^{n - 1}$$ where $$\varepsilon^{n} = 0$$. We study the norm on $$\Delta_{n}$$ defined by
$$\bigl\lVert a_{0} + a_{1} \varepsilon+ \cdots+ a_{n - 1} \varepsilon^{n - 1} \bigr\rVert = \sqrt {a_{0}^{2} + a_{1}^{2} + \cdots+ a_{n - 1}^{2}}.$$
(24)
### Theorem 5.1
The submultiplicative constant for $$\Delta_{n}$$ is
1. (1)
for$$n=2$$, $$m_{2}(\Delta_{2}) = \frac{2}{\sqrt{3}}$$;
2. (2)
for$$n=3$$, $$m_{2}(\Delta_{3}) = \frac{4}{3}$$.
### Proof
In all of the cases, we mainly use the AM–GM inequality. Begin with claim (1). Suppose $$x = a_{0} + a_{1} \varepsilon, y = b_{0} + b_{1} \varepsilon$$ and observe:
\begin{aligned} 4 \lVert x \rVert^{2} \cdot \lVert y \rVert^{2} & = 4 \bigl(a_{0}^{2} + a_{1}^{2}\bigr) \bigl(b_{0}^{2} + b_{1}^{2}\bigr) \\ & = 3 \bigl(a_{0}^{2} b_{0}^{2} + a_{1}^{2} b_{0}^{2} + a_{0}^{2} b_{1}^{2}\bigr) + \bigl(a_{0}^{2} b_{0}^{2} + 4a_{1}^{2} b_{1}^{2}\bigr) + \bigl(a_{1}^{2} b_{0}^{2} + a_{0}^{2} b_{1}^{2}\bigr) \\ & \ge3 \bigl(a_{0}^{2} b_{0}^{2} + a_{1}^{2} b_{0}^{2} + a_{0}^{2} b_{1}^{2}\bigr) + 4 a_{0} b_{0} a_{1} b_{1} + 2 a_{1} b_{0} a_{0} b_{1} \\ & = 3 \bigl[ (a_{0} b_{0})^{2} + (a_{1} b_{0} + a_{0} b_{1})^{2} \bigr] = 3 \bigl\lVert a_{0} b_{0} + (a_{1} b_{0} + a_{0} b_{1}) \varepsilon \bigr\rVert ^{2} \\ & = 3 \lVert x y \rVert^{2}. \end{aligned}
(25)
If we set $$a_{0} = b_{0} = \sqrt{2}$$ and $$a_{1} = b_{1} = 1$$ then equality is attained. Next, prove claim (2). We suppose $$x = a_{0} + a_{1} \varepsilon + a_{2} \varepsilon^{2}$$ and $$y = b_{0} + b_{1} \varepsilon+ b_{2} \varepsilon ^{2}$$. Calculate:
\begin{aligned} 16 \lVert x \rVert^{2} \cdot \lVert y \rVert^{2} ={}& 16 \bigl(a_{0}^{2} + a_{1}^{2} + a_{2}^{2}\bigr) \bigl(b_{0}^{2} + b_{1}^{2} + b_{2}^{2}\bigr) \\ ={}& 9 \bigl( a_{0}^{2} b_{0}^{2} + a_{1}^{2} b_{0}^{2} + a_{0}^{2} b_{1}^{2} + a_{0}^{2} b_{2}^{2} + a_{1}^{2} b_{1}^{2} + a_{2}^{2} b_{0}^{2} \bigr) + 16 a_{1}^{2} b_{2}^{2} + 4 a_{0}^{2} b_{1}^{2} \\ &{} + 16 a_{2}^{2} b_{1}^{2} + 4 a_{1}^{2} b_{0}^{2} + 16 a_{2}^{2} b_{2}^{2} + a_{0}^{2} b_{0}^{2} + 3 \bigl( a_{0}^{2} b_{1}^{2} + a_{1}^{2} b_{0}^{2} \bigr) \\ &{} + 6 \bigl( a_{0}^{2} b_{0}^{2} + a_{1}^{2} b_{1}^{2} \bigr) + \frac{1}{2} a_{1}^{2} b_{1}^{2} + 2 a_{2}^{2} b_{0}^{2} + \frac{1}{2} a_{1}^{2} b_{1}^{2} + 2 a_{0}^{2} b_{2}^{2} + 5 \bigl( a_{0}^{2} b_{2}^{2} + a_{2}^{2} b_{0}^{2} \bigr) \\ \ge{}&9 \bigl( a_{0}^{2} b_{0}^{2} + a_{1}^{2} b_{0}^{2} + a_{0}^{2} b_{1}^{2} + a_{0}^{2} b_{2}^{2} + a_{1}^{2} b_{1}^{2} + a_{2}^{2} b_{0}^{2} \bigr) \\ &{} + 16 a_{1} b_{2} a_{0} b_{1} + 16 a_{2} b_{1} a_{1} b_{0} + 8 a_{2} b_{2} a_{0} b_{0} + 6 a_{0} b_{1} a_{1} b_{0} \\ &{} + 12 a_{0} b_{0} a_{1} b_{1} + 2 a_{1} b_{1} a_{2} b_{0} + 2 a_{1} b_{1} a_{0} b_{2} + 10 a_{0} b_{2} a_{2} b_{0} \\ ={}& 9 \bigl[ (a_{0} b_{0})^{2} + (a_{1} b_{0} + a_{0} b_{1})^{2} + (a_{0} b_{2} + a_{1} b_{1} + a_{2} b_{0})^{2} \bigr] \\ ={}& 9 \bigl\lVert a_{0} b_{0} + (a_{1} b_{0} + a_{0} b_{1}) \varepsilon+ (a_{0} b_{2} + a_{1} b_{1} + a_{2} b_{0}) \varepsilon^{2} \bigr\rVert ^{2} \\ ={}& 9 \lVert xy \rVert^{2}. \end{aligned}
(26)
Equality occurs if, for instance, $$a_{0} = b_{0} = a_{1} = b_{1} = 2, a_{2} = b_{2} = 1$$. □
It is interesting to note that in both cases ($$n = 2, 3$$) we find equality occurs when
$$\frac{a_{0}}{b_{0}} = \frac{a_{1}}{b_{1}} = \frac{a_{2}}{b_{2}}.$$
(27)
Assuming the above trend continues, we conjecture that:
1. (1)
for $$n = 4$$, $$m_{2}(\Delta_{4}) = \sqrt{\frac{2 (1103 + 33\sqrt {33})}{1153}} \approx1.49736$$. We note equality in $$\| xy \| \leq m_{2}(\Delta_{4}) \| x \| \|y \|$$ is attained for $$x = y = \sqrt{5 + \sqrt{\frac{11}{3}}} + ( 1 + \sqrt{\frac {11}{3}} ) \varepsilon+ \sqrt{3 + \sqrt{\frac{11}{3}}} \varepsilon^{2} + \varepsilon^{3} \approx2.62961 + 2.91485 \varepsilon+ 2.21695 \varepsilon^{2} + \varepsilon^{3}$$.
2. (2)
for $$n = 5$$, the closed form expression is too lengthy for us to display here, however, an approximation of the constant is $$m_{2}(\Delta _{5}) \approx1.64748$$. Equality in $$\| xy \| \leq m_{2}(\Delta_{5}) \| x \| \|y \|$$ is attained when $$x = y \approx1 - 1.14862 \varepsilon+ 1.03046 \varepsilon^{2} - 0.700308 \varepsilon^{3} + 0.304849 \varepsilon^{4}$$.
3. (3)
for $$n = 6$$, the submultiplicative constant is $$m_{2}(\Delta_{6}) \approx1.78611$$ and equality in $$\| xy \| \leq m_{2}(\Delta_{6}) \| x \| \|y \|$$ is attained at $$x = y \approx1 - 1.16152 \varepsilon+ 1.12963 \varepsilon^{2} - 0.915093 \varepsilon^{3} + 0.589126 \varepsilon^{4} - 0.253601 \varepsilon^{5}$$.
### Theorem 5.2
For$$r \in\mathbb{N}, r \ge2$$, we have$$m_{r}(\Delta_{2}) = \sqrt{\frac{r + 1}{ ( 1 + \frac{1}{r} )^{r}}}$$.
### Proof
Considering $$a_{i}, b_{i} \in\mathbb{R}$$ for $$1 \le i \le r$$, since $$\varepsilon^{2}=0$$, we find
$$\prod_{i = 1}^{r} (a_{i} + b_{i} \varepsilon) = \prod_{i = 1}^{r} a_{i} + \varepsilon\sum_{i = 1}^{r} \biggl( \prod_{j \neq i} a_{j} \biggr) b_{i}.$$
(28)
Let $$g^{2}$$ be the smallest constant such that the inequality below holds for arbitrary $$a_{i}, b_{i}$$,
$$g^{2} \prod_{i = 1}^{r} \bigl(a_{i}^{2} + b_{i}^{2}\bigr) \ge \prod_{i = 1}^{r} a_{i}^{2} + \Biggl[ \sum_{i = 1}^{r} \biggl( \prod _{j \neq i} a_{j} \biggr) b_{i} \Biggr]^{2}.$$
(29)
Substituting $$a_{i} = 1$$ and $$b_{i} = 0$$, we have $$g^{2} \ge1$$. If there is at least one $$a_{i} = 0$$ then, without loss of generality, we may suppose $$a_{r} = 0$$, and thus for all $$a_{i}, b_{i} \in\mathbb{R}$$
$$g^{2} \prod_{i = 1}^{r - 1} \bigl(a_{i}^{2} + b_{i}^{2}\bigr) b_{r}^{2} \ge\prod_{i = 1}^{r - 1} \bigl(a_{i}^{2} + b_{i}^{2}\bigr) b_{r}^{2} \ge a_{1}^{2} a_{2}^{2} \cdots a_{r - 1}^{2} b_{r}^{2}.$$
(30)
Thus (29) holds trivially. Therefore, let us suppose all $$a_{i}$$ are non-zero. Then we can normalize the above inequality to (setting $$x_{i} = b_{i} / a_{i}$$)
$$g^{2} \prod_{i = 1}^{r} \bigl(1 + x_{i}^{2}\bigr) \ge1 + \Biggl( \sum _{i = 1}^{r} x_{i} \Biggr)^{2}.$$
(31)
Define $$f(x_{1}, \ldots, x_{r}) = \frac{1 + (x_{1} + \cdots+ x_{r})^{2}}{(1 + x_{1}^{2}) \cdots(1 + x_{r}^{2})}$$ and note by construction $$g^{2} \geq f(x_{1}, \ldots, x_{r})$$ for all $$x_{1}, \dots, x_{r}$$. We seek solutions to $$\nabla f = 0$$ in the interest of finding the global maximum of f. Set $$S = x_{1} + x_{2} + \cdots+ x_{n}$$ and calculate
$$\frac{\partial f}{\partial x_{i}} = -2 \frac{(S - x_{i})(x_{i} S - 1)}{(1 + x_{i}^{2}) \prod_{k = 1}^{r} (1 + x_{k}^{2})}.$$
(32)
Hence, $$\nabla f = 0$$ if and only if $$(S - x_{i})(x_{i} S - 1) = 0$$ for all $$1 \le i \le r$$.
1. (1)
If $$S = 0$$ then $$(S - x_{i})(x_{i} S - 1) = 0$$ implies $$x_{1}=0, x_{2}=0, \dots, x_{r}=0$$.
2. (2)
Suppose $$x_{1}, x_{2}, \ldots, x_{r} \neq0$$. Then $$(S - x_{i})(x_{i} S - 1) = 0$$ yields
$$S + \frac{1}{S} = x_{1} + \frac{1}{x_{1}} = x_{2} + \frac{1}{x_{2}} = \cdots = x_{r} + \frac{1}{x_{r}},$$
and we find solution $$x_{1} = x_{2} = \cdots= x_{r} = \pm\frac{1}{\sqrt{r}}$$.
Observe $$f(0, \ldots, 0) = 1$$ whereas $$f ( \frac{1}{\sqrt{r}}, \ldots, \frac{1}{\sqrt{r}} ) = f ( -\frac{1}{\sqrt{r}}, \ldots, -\frac{1}{\sqrt{r}} ) = \frac{r + 1}{ ( 1 + \frac{1}{r} )^{r}} \ge1$$ for all $$r \geq2$$. Therefore we conclude $$m_{r} (\Delta_{2}) = \sqrt{g} = \sqrt{\frac{r + 1}{ ( 1 + \frac{1}{r} )^{r}}}$$. □
Let $$\Delta_{n}$$ have p-norm defined for $$p< \infty$$ by
$$\bigl\Vert a_{1}+a_{2}\varepsilon+ \cdots+a_{n} \varepsilon^{n-1} \bigr\Vert = \sqrt [p]{a_{1}^{p}+a_{2}^{p}+ \cdots+a_{n}^{p}}.$$
(33)
### Theorem 5.3
Suppose$$p \in(1, \infty)$$. If$$\Delta_{n}$$is endowed withp-norm then$$\rho_{\Delta_{n}} = 1$$.
### Proof
Let it be understood that $$m_{r}(\Delta_{n})$$ is defined with respect to the p-norm throughout this proof. Suppose $$a_{i,j} > 0$$. We will attempt to bound $$m_{r} (\Delta_{n})$$ by an appropriate constant. We have
$$\prod_{i = 1}^{r} \sum _{j = 0}^{n - 1} a_{i,j} \varepsilon^{j} = \sum_{k = 0}^{n - 1} \Biggl( \sum _{d_{1} + \cdots+ d_{r} = k} \prod_{i = 1}^{r} a_{i, d_{i}} \Biggr) \varepsilon^{k}.$$
(34)
Therefore,
$$m_{r}(\Delta_{n})^{p} \prod _{i = 1}^{r} \sum_{j = 0}^{n - 1} a_{i, j}^{p} \ge \sum_{k = 0}^{n - 1} \Biggl( \sum_{d_{1} + \cdots+ d_{r} = k} \prod _{i = 1}^{r} a_{i, d_{i}} \Biggr)^{p}.$$
(35)
A few observations about (35) are as follows:
1. (1)
There are $$\binom{k + r - 1}{k}$$ distinct terms $$\prod_{i = 1}^{r} a_{i, d_{i}}$$ in the sum
$$\sum_{d_{1} + \cdots+ d_{r} = k} \prod_{i = 1}^{r} a_{i, d_{i}}.$$
2. (2)
Each term $$\prod_{i = 1}^{r} a_{i, d_{i}}$$ to the power p occurs in the product
$$\prod_{i = 1}^{r} \sum _{j = 0}^{n - 1} a_{i, j}^{p}.$$
3. (3)
$$\binom{(k + 1) + r - 1}{k + 1} = \binom{k + r - 1}{k} + \binom {k + r - 1}{k + 1} \ge\binom{k + r - 1}{k}$$, so the sequence $$\binom {k + r - 1}{k}$$ is increasing in variable k and thus $$\max_{0 \le k < n} \bigl\{ \binom{k + r - 1}{k}\bigr\} = \binom{n + r - 2}{n - 1} = O(r^{n - 1})$$.
4. (4)
By Hölder’s inequality with $$q = \frac{p}{p - 1}$$,
$$x_{1} \cdot1 + x_{2} \cdot1 + \cdots+ x_{s} \cdot1 \le \bigl( x_{1}^{p} + x_{2}^{p} + \cdots+ x_{s}^{p} \bigr)^{\frac{1}{p}} \bigl( 1^{q} + 1^{q} + \cdots + 1^{q} \bigr)^{\frac{1}{q}}.$$
Consequently, $$( x_{1} + x_{2} + \cdots+ x_{s} )^{p} \le s^{p - 1} ( x_{1}^{p} + x_{2}^{p} + \cdots+ x_{s}^{p} )$$.
Combining the observations above, we find:
\begin{aligned} \sum_{k = 0}^{n - 1} \Biggl( \sum _{d_{1} + \cdots+ d_{r} = k} \prod_{i = 1}^{r} a_{i, d_{i}} \Biggr)^{p} & \le\sum_{k = 0}^{n - 1} \binom{k + r - 1}{k}^{p - 1} \Biggl( \sum_{d_{1} + \cdots+ d_{r} = k} \prod_{i = 1}^{r} a_{i, d_{i}}^{p} \Biggr) \\ & \le\binom{n + r - 2}{n - 1}^{p - 1} \sum_{k = 0}^{n - 1} \Biggl( \sum_{d_{1} + \cdots+ d_{r} = k} \prod _{i = 1}^{r} a_{i, d_{i}}^{p} \Biggr) \\ & \le\binom{n + r - 2}{n - 1}^{p} \prod_{i = 1}^{r} \sum_{j = 0}^{n - 1} a_{i, j}^{p}. \end{aligned}
(36)
Thus,
$$m_{r}(\Delta_{n}) \le\binom{n + r - 2}{n - 1} = O\bigl( r^{n-1}\bigr).$$
(37)
Since n is fixed, $$\rho_{\Delta_{n}} \le\limsup_{r \rightarrow \infty} \sqrt[r]{ r^{n-1}} = 1$$. However, we found in (3) that $$\rho_{\Delta_{n}} \ge \lVert 1 \rVert^{-1} = 1$$. Thus, $$\rho_{\Delta_{n}} = \lVert1 \rVert^{-1} = 1$$. □
## 6 Submultiplicative constants for the dualplex numbers
An n-dualplex number is defined as an element of $$\mathcal {A}=\mathbb {R}[x] / \langle(x^{2}+1)^{n} \rangle$$, or equivalently, $$a_{0} + a_{1} q + \cdots+ a_{2n-1} q^{2n-1}$$ where $$a_{i} \in\mathbb{R}$$ and $$(q^{2} + 1)^{n} = 0$$. If we use norm
$$\bigl\lVert a_{0} + a_{1} q + \cdots+ a_{2n-1} q^{2n-1} \bigr\rVert = \sqrt{a_{0}^{2} + a_{1}^{2} + \cdots+ a_{2n - 1}^{2}}$$
then for $$n=1$$ we have complex numbers with the usual multiplicative norm and multiplicative constant 1. However, for $$n=2$$ we conjecture that the submultiplicative constant is given by $$m_{\mathcal {A}}= \sqrt{\frac{71 + 17 \sqrt{17}}{6}}$$ where $$\| xy \| = m_{\mathcal {A}}\| x \| \| y\|$$ if we set $$x = y = (3 - \sqrt{17}) q + 2 q^{3}$$.
## 7 Convergence of geometric series over some algebras
In this section we use Theorem 1.3 in conjunction with the results of the previous sections to study the geometric series over an algebra.
### Example 7.1
Consider the geometric series $$\sum_{n = 0}^{\infty}z^{n}$$ in the N-hyperbolic numbers $$\mathcal {H}_{N}$$. Observe $$c_{n}=1$$ and $$C = \limsup_{n \rightarrow\infty} \sqrt[n]{ \lVert c_{n} \rVert} = 1$$. We found $$\rho _{\mathcal {H}_{N}} = \sqrt{N}$$ in Theorem 3.3. Theorem 1.3 gives that the geometric series converges for $$\| z \| < \frac{1}{\sqrt{N}}$$. Suppose $$R > \frac {1}{\sqrt{N}}$$, pick $$z = \frac{R}{\sqrt{N}} ( 1 + j + j^{2} + \cdots+ j^{N - 1} )$$, and notice $$\lVert z \rVert = R$$ and that the geometric series diverges at z by the Root Test as
\begin{aligned} \limsup_{n \rightarrow\infty} \sqrt[n]{ \bigl\lVert z^{n} \bigr\rVert } & = \limsup_{n \rightarrow\infty} \sqrt[n]{\frac{R^{n}}{\sqrt{N}^{n}} \bigl\lVert N^{n - 1} \bigl( 1 + j + j^{2} + \cdots+ j^{N - 1} \bigr) \bigr\rVert } \\ & = \limsup_{n \rightarrow\infty} \sqrt[n]{R^{n} \sqrt{N}^{n - 1}} = R \sqrt{N} > 1. \end{aligned}
(38)
We see the radius of convergence $$1/\sqrt{N}$$ is maximal.
### Example 7.2
Consider the Dual Numbers $$\Delta_{N}$$ for some $$N\geq2$$. Apply Theorems 5.3 and 1.3 to see why the geometric series $$\sum_{n = 0}^{\infty}z^{n}$$ converges for $$\| z \| < 1$$. Also, if $$R>1$$ then setting $$z=R$$ gives a point with $$\| z \| > 1$$ where the geometric series diverges.
## Notes
### Acknowledgements
We thank Liberty University for supporting Math 495 in the Spring 2018 Semester.
Not applicable.
### Authors’ contributions
The authors read and approved the final manuscript.
Not applicable.
### Competing interests
The authors declare that they have no competing interests.
## References
1. 1.
Cook, J.S.: Introduction to $$\mathcal {A}$$-Calculus. https://arxiv.org/abs/1708.04135
2. 2.
Cook, J.S., Freese, D.: Analysis of power series in the $$\mathcal{A}$$-calculus. Int. Math. Forum 13(10), 473–483 (2018)
3. 3.
Good, I.J.: Skew circulants and the theory of numbers. Fibonacci Q. 24(1), 47–60 (1986)
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https://www.physicsforums.com/threads/intriguing-questions-regarding-nature-of-time-in-special-relativity.289565/ | # Intriguing Questions Regarding Nature of Time in Special Relativity!
1. Feb 3, 2009
### Curious6
Hi,
I have been thinking about the philosophical implications of time and have in the process been analyzing the consequences of time as conceived of by special relativity. I have a couple of questions though, and I would really appreciate it if someone could offer their knowledge in an attempt to answer them:
1. How does time emerge in special relativity? Could we conceive as time as simply measuring the duration of a process?
i2. In an inertial reference frame, if two particles are at rest with respect to each other, is time passing for them?
Any insights on these questions would be very welcome indeed.
Thanks!
2. Feb 3, 2009
### Fredrik
Staff Emeritus
1. Two concepts of time are defined by the theory, proper time and coordinate time. It's postulated that a clock measures the proper time of the curve in spacetime that represents the clock's motion. (I'm not sure if that answers your question).
2. Yes. Their motions are represented by two straight and parallel lines in spacetime, but the time coordinate is not the same at any two points on the same curve, and the proper time integral is also non-zero along these curves. It's value increases as you consider longer segments of the curve.
3. Feb 3, 2009
### Curious6
Thank you for your answers. Following on from them, I have another two questions:
1. Could you define a little more closely (perhaps with an example) the difference between proper time and coordinate time.
2. You say that the value of the time coordinate increases along the curves (which may be interpreted as space) so could we therefore say that time can be conceived of as being the extent of space? In other words, could we imagine time as being inherent or a property of space ?
3. Is time in a sense therefore just a measure of oscillations of space?
4. Feb 3, 2009
### Fredrik
Staff Emeritus
1. See e.g. this post. In 1+1 dimensions, units such that c=1, and in the coordinates of an inertial frame, the square root simplifies to $\sqrt{dt^2-dx^2}$. If you and I are initially at the same location, and I go for a run while you stay put, our paths through spacetime from when we got separated to when we meet again have different proper times. Your path has a greater proper time since there's no contribution from dx when we integrate along your path. This means that you have aged more than I when we meet again.
2. It's a property of a curve in spacetime. To be precise, it's the closest thing to a "length" of the curve that we can define. Proper time is often described as the "length" of the curve, but it's a bit counterintuitive. You might think that if you stay put, and I go for a run, my path is going to be longer, but my movement through space makes my path shorter, not longer, because of the minus sign in front of dx2.
3. It's the "length" of a curve. The clock that measures this "length" might however do it by counting the number of some sort of oscillations.
Last edited: Feb 4, 2009
5. Feb 4, 2009
### bernhard.rothenstein
I enjoy the following definitions:
Proper time (interval) the time interval between two events as measured by a single clock that is present at both events. Its value depends on the world line that the clocki follows in getting from one event to the other. We can say that it is the time interval measured by the wrist watch of an observer.
Coordinate time (interval) the time interval between two events in an inertial reference frame by a pair of synchronized clocks, one present at one event the other present at the other event.
(Thomas A. Moore, A Traveler's Guide to Space Time)
Two clocks of the same inertial reference frame and standard synchronized display the same running time.
6. Feb 4, 2009
### Curious6
Thank you both very much for your help and insights.
7. Feb 4, 2009
### neopolitan
So is this true:
(coordinate time*c)2=(proper time*c)2+(spatial separation between events)2=(proper time*c)2+(coordinate time*v)2
or this:
(coordinate time*c)2=(proper time*c)2+(proper time*v)2
or is there yet another equation?
The reason I ask is that it seems to me that there is one, and only one path in spacetime between two events. It can defined by proper time (in the rest frame in which the events are collocated) or by a combination of coordinate time and spatial separation.
It's just a little unclear as to how that separation should be defined. I think it is the latter equation above, but it is counter intuitive because it uses the time of a clock which can consider itself to be at rest and the speed at which another observer considers the clock to be moving.
cheers,
neopolitan
8. Feb 4, 2009
### Staff: Mentor
Careful here! Think "twins paradox". The separation and the reunion are two events and each twin takes a different path through spacetime between those events. Geometrically your statement is akin to saying that there is one and only one curve which joins two points in a plane.
9. Feb 4, 2009
### neopolitan
You are right. I didn't express myself well enough.
The two events I am thinking of are the two events from the situation which Bernard quoted. In other words you have one observer in one inertial frame for whom the events are collocated and you have another observer in one inertial frame (bye bye twin's paradox) for whom the events are not collocated. This would be akin to only one leg of the twin's paradox.
Geometrically, I would be thinking of a line drawn on a sheet of paper. It could be pointed "up" - corresponding to stationary. Or it could be pointed off to one side - corresponding to "as viewed by someone in motion". Would the magnitude of the line change depending on your perspective, or would it be the same, just with vector addition of time and spatial components?
cheers,
neopolitan
10. Feb 5, 2009
### Naty1
Curious: you can see how Einstein explains time at
http://www.bartleby.com/173/
perhaps beginning at #8 ON THE IDEA OF TIME IN PHYSICS
where it seems to me he assumes in special relativity time in one location passes at the same rate as in another location. It's absolute in the Newtonian sense. In the next section he argues that time on a train passes differently viewed from an embankment and in the next that distance, too varies, with motion...he already had Lorentz- Fitgerald transformations to guide him so likely they were a key input..those are discussed in the next section, #11.
11. Feb 5, 2009
### Curious6
I have come up with another question: If time is indeed a curve in spacetime, then is the reason we see time as passing due to the Earth moving along the curve?
12. Feb 6, 2009
### Staff: Mentor
Even a "stationary" object still "moves" in the time direction through spactime. | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.7775951623916626, "perplexity": 516.9731182743509}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2017-09/segments/1487501171463.89/warc/CC-MAIN-20170219104611-00506-ip-10-171-10-108.ec2.internal.warc.gz"} |
https://cs.stackexchange.com/questions/26322/average-between-n-numbers | # Average between n numbers [closed]
Is it possible to calculate the average between n numbers in a static random access array of some size in less than $O(n)$ time? I know that the trivial approach is $O(n)$, but can I do it in less time using a data structure or a certain preparation? or both? I am asking for hints, not a solution.
Note: The array is of some length. What and I mean by between is when given 2 indexes a and b, I have to calculate the average of the sub array $[a+1,b-1]$. And I have to keep it updated while the data structure is managed, that's why I said it was a dynamic set, in other words a random access array. I do not know of any restrictions, just asking if it's possible in less than $O(n)$.
## closed as unclear what you're asking by FrankW, David Richerby, Juho, D.W.♦, Rick DeckerJun 2 '14 at 21:23
Please clarify your specific problem or add additional details to highlight exactly what you need. As it's currently written, it’s hard to tell exactly what you're asking. See the How to Ask page for help clarifying this question. If this question can be reworded to fit the rules in the help center, please edit the question.
• Is the array of length n? what precisely do you mean by "between"? – d'alar'cop Jun 2 '14 at 13:26
• What is $n$? The number of elements? Do you need to compute the average once or keep it updated while the data structure is managed? If the latter, is the running time restricted for a sngle run or for all of them combined? – FrankW Jun 2 '14 at 13:27
• The array is of some length. What and I mean by between is when given 2 indexes a and b, I have to calculate the average of the sub array [a+1,b-1]. And I have to keep it updated while the data structure is managed, that's why I said it was a dynamic set, in other words a random access array. I do not know of any restrictions, just asking if it's possible in less than $O(n)$. – HaloKiller Jun 2 '14 at 13:31
• So you keep the average updating as you add/remove elements?... the subindices stay the same? – d'alar'cop Jun 2 '14 at 13:36
• @Trinarics You are only specifying your full question in the comments! Please explain your question in the question statement itself. The way it is currently stated, the average can be maintained in $O(1)$ time. – Yuval Filmus Jun 2 '14 at 15:20
I'll assume that you are computing the average of the elements of an array of fixed size and that you can change the value at some position at any moment. You want a data structure that supports the following two operations:
1. Update element at location $i$,
2. Query sum of elements in range [$i$, $j$].
A binary indexed tree (aka Fenwick tree) performs both in $\cal O(\lg n)$.
I am assuming that the query must be done in less than O(n) time and preprocessing can take any amount of time.
Pre-processing: Store the values in a Binary Tree like data structure.Every node of tree has sum of its subtree and number of children(To calculate average).So the base case is that you have n leaves having n values and we go leaves to root to construct this tree.You can do this pre-processing in O(nlogn) time.
Query: Now whenever you update a value you need to go to leaf along the path from top node to this leaf and the sum only changes in the nodes along this path so this takes only O(logn) time.
Correct me if I am wrong.
• How do you compute the average for a subarray that does not align with a subtree? – FrankW Jun 2 '14 at 13:43
• My approach cannot compute it,I assumed question asks average of n elements where n is given to you and n is the size of array – iLoveCamelCase Jun 2 '14 at 14:38
• Also user mentioned update is O(1) so my method would be invalid anyway. – iLoveCamelCase Jun 2 '14 at 14:39
• My method has same complexity as above answer – iLoveCamelCase Jun 2 '14 at 14:45 | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.44696056842803955, "perplexity": 635.5067168995544}, "config": {"markdown_headings": true, "markdown_code": false, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2019-35/segments/1566027316785.68/warc/CC-MAIN-20190822064205-20190822090205-00277.warc.gz"} |
http://www.cs.jhu.edu/~prastog3/2015/06/16/multiview-lsa-proofs-and-faq.html | When I was presenting my Multiview LSA (MVLSA) paper at NAACL I seriously felt that I had left out a lot of the background/motivation/proofs behind GCCA from the paper due to lack of space and only gave the most essential pieces of the algorithm. I still think that it was a good call since the main point of the paper was to evaluate GCCA’s performance and my own contribution was to A) Make sure that its computation was fast B) Leverage some methods to handle sparsity C) Do rigorous testing D) Get the best results possible by tuning hyperparameters. It’s not like I derived GCCA itself.
Anyway, a few people expressed interested in the derivation/motivation behind the method so I will write it down here. So this article would serve as a supplemental to the main paper.
In this article I am going to start from scratch and first present (in words) the motivation that led to GCCA and then show how equation 1 and equation 3 from the paper result from it.
Once again, I’ll note that I am merely rephrasing things that were already derived by (Carroll, 1968) and (Kettenring, 1971). However, I do think that Kettenring’s notation is too old and readers might prefer the simpler notation that I’ll use.
##What is the motivation for equation 1 in the paper ?##
Alternatively, the question could be that why do I say that the objective of MAXVAR-GCCA is:
Just like PCA has at least 3 different interpretations/derivations GCCA too has multiple interpretations. Let me first state the motivations in words:
1. MAXVAR GCCA finds a representation that maximizes total squared correlation between an auxilliary variable and possible rank-$r$ linear transformations/distortions of the data. (This is Carroll’s starting point)
2. MAXVAR GCCA of rank $r$ finds an orthogonal representation $G$ that minimizes the total squared distance from rank-$r$ subspace spanned by the data points available in different views. ((Sengupta, 1983) reports that it was (Coelho, 1992) who first gave this “geometric” interpretation.)1
3. There are two other closely related motivations that lead to the same solution:
a. MAXVAR GCCA finds projections of the data that make the inter projection correlation matrix as close to a rank 1 matrix as possible (This was how (Horst, 1961) derived MAXVAR GCCA )
b. MAXVAR GCCA finds projections of the data that maximize the highest eigen value of the inter projection correlation matrix. (This was the Interpretation that (Kettenring, 1971) gave. In his paper he basically unified 4-5 different types of GCCA as optimizations of different measures of the inter-correlation matrix. This was why he worded rephrased Horst’s criteria like this)
Now the trouble is that even though the above statements are simple to read they are woefully imprecise. What is “inter projection correlation matrix”? What is “total squared distance”? What does it mean that a matrix is “as close to a rank 1 matrix” as possible? 2 To really understand how all these criteria can have the same solution we need precise notation.
Notation Matrix Random variable Unknown constant Known constant Other Types Examples
Scalar (rs) $x$ (us) $\us{x}$ (ks)$\ks{x}$ Sets 1 $\mathbb{R}$
Vector (rv) $\rv{x}$ (uv) $\uv{x}$ (kv) $\kv{x}$ Sets 2 $\mathcal{S}$
Matrix\Tensor (rm) $\rm{X}$ (um) $\um{X}$ (km) $\km{X}$
Let us look at Carroll’s original criteria (Motivation 1)
Imagine that we have $\ks{J}$ random variables $\rv{x}_j \; j \in [1, \ldots, \ks{J}]$ all of which have zero mean. We want to find a single scalar linear projection $\rs{z}_j$ of each data source, i.e.
and some “auxilliary” mean-zero random variable $\rs{g}$ such that $\rs{g}$ and $\rs{z_j}$ have as high total squared correlation as possible. I.e. we maximize \eqref{eq:carroll}:
At first sight it is not obvious why \eqref{eq:carroll} is a good objective. It has some redeeming qualities such as the fact that it is constraining the auxiliary variable to correlate well with any linear projection of the data. So there is some flexibility in the model but not too much. But what if we want to correlate more with one of the data sources ? One could easily add some multiplicative weights to this criteria to get some more flexibility. Would that be enough ? Probably not. We will further analyze criteria \eqref{eq:carroll} later on, for now lets do the optimization.
Let’s say that we have $\ks{n}$ data points. Let’s denote the sample space manifestation of $\rs{g}$ as $\uv{g}$ and of $\rs{z}_j$ as $\uv{z}_j$. Note that these are both unknown vectors in the sample space. Now $\text{correlation}(\rs{g}, \rs{z}_j)^2$ can be estimated as follows:
Since we have control over both $\rs{g}$ and $\rs{z}_j$ we could constrain both of them to have unit $l_2$ norm and then try to solve the optimization problem. The optimization problem would look like
Or
But this optimization problem is hard and there is a trick to solve this. Note that we don’t really need to constrain both $\uv{g}$ and $\uv{z}_j$. We can instead constrain only $||\uv{g}||_2^2 = 1$ and then maximize the squared length of the projection of $\uv{g}$ onto $\uv{z}_j$ which is numerically the same as the cosine similarity (correlation) between $\uv{g}$ and $\uv{z}_j$. So the optimization criteria becomes
We further note that for any value of $\uv{g}$ the following relation holds (by the pythagoras theorem)
Therefore the optimization criteria translates to:
Now we only have to generalize to the case where instead of searching for a scalar projection of the data $\rs{z}_j$ we are instead looking for multiple projections. Clearly we must add constrain the projections in some way otherwise all of them could end up the same. It turns out that the constraint $\text{correlation}(\rs{g}_i, \rs{g}_j) = 0 \;\; \forall i, j : j \ne i$ over auxiliary representations $\rs{g}_1, \rs{g}_2, \ldots$ is enough to ensure that we learn interesting projections. And this leads to the optimization problem \eqref{eq:mvlsa} from the paper. Q.E.D.
##So how do we optimize criteria \eqref{eq:mvlsa}##
Since \eqref{eq:mvlsa} is a real valued function that is bounded below by $0$ therefore it must have at least one global minima. Assume that $\um{G}^*$ is the value of $\um{G}$ at one such minima. Now each member of $|| \um{G} - \um{X}_j \um{U}_j ||_F^2$ of the objective is a linear regression with $\um{U}_j$ as the unknown. So the solution for $\um{U}_j$ is $(\um{X}_j^{\intercal} \um{X}_j)^{-1}\um{X}_j^{\intercal}\um{G}$. Let $\um{P}_j = \um{X}_j(\um{X}_j^{\intercal} \um{X}_j)^{-1}\um{X}_j^{\intercal}$ and note that $||\um{M}||^2_F = \text{trace}(\um{M}^\intercal \um{M})$. So our objective translates to:
Now we know that this is an eigenvector problem and its solutions are the eigen vectors of $\sum_{j=1}^{\ks{J} } ({I} - \um{P}_j)^\intercal ({I} - \um{P}_j)$. Consider
Also note that the eigen vectors of ${I} - \km{M}$ are the same as the eigen vectors of $M$. Therefore the optimal $G$ can be found by computing the eigen vectors of $\sum_{j=1}{\ks{J} } P_j$.
Corner Cases: The attentive reader would notice that there are corner cases that we did not address, like what happens if $(\um{X}_j^{\intercal} \um{X}_j)^{-1}$ is not defined. While it is possible to cover these corner cases, we took the simpler root and defined $P_j$ through $(\um{X}_j^{\intercal} \um{X}_j) + r I$. That ensures that all the assumptions about existence, symmetry and idempotency of the projection matrix hold true.
##What about criteria 3a and 3b##
When I started writing this post, I did not realize that writing proofs is so hard. Now I can appreciate why people take short cuts and leave exercises. But any way let’s press on.
Let’s first establish that 3a is the same as 3b. Actually I think I can leave that as an exercise since this is just the [Eckart-Young]https://en.wikipedia.org/wiki/Singular_value_decomposition#Applications_of_the_SVD) theorem restated. And 3b has been derived quite clearly in (Kettenring, 1971) so I won’t repeat him.
##So what’s left to do ?##
Here’s what I think my next steps should be: 1. (Kakade & Foster, 2007) and (Sridharan & Kakade, 2008) did information-theoretic/CoLT-type analysis of Multi-view learning and CCA. What is not clear to me and what would be nice to have are measurable condition about what constitutes a separate view ? After all we could just concatenate the matrices into a single view and then do LSA or Glove or Whatever ? When would hunting for correlation be better than hunting for variance ?
1. In our paper we never compared GCCA to basic LSA !! I think that was an oversight and that experiment must be run. Also I can probably feed all my co-occurrence matrices to Glove and run it. What would it learn ?
2. I talked about how Venvelden and Takane had collaborated and come up with better regularization methods. But I never applied them to our task ? Also I showed how we could approximate Glove by a special regularization scheme. Both of these experiments should be run and applied to the task.
3. Probabilistic GCCA. This has been on my plate for a while, and I think I’d try to blog the solution but the gist is that Tipping, Bishop and Sam Roweis did a factor analysis of PCA, Francis Bach and Michael Jordan gave probabilistic CCA. It should be pretty straight forward to do probabilistic GCCA. The key point is not whether its possible, it almost certainly is, but that once I do how would I use it ? What good is probabilistic GCCA once you know the formulas ?
4. Task specific GCCA. Till date all my experiments have been unsupervised but like I remarked earlier it is possible to add parameters to the model that can be tuned discrimatively.
## Footnotes
1. This is like the statistical-geometric interpretations of PCA.
2. But the problem is also that if we give the rigorous definitions without a summary of what those definitions and derivations should be interpreted as, then it becomes hard to maintain interest. So it's a chicken and egg problem.
## Bibliography
1. Carroll, J. D. (1968). Generalization of canonical correlation analysis to three or more sets of variables. In Proceedings of APA (Vol. 3).
2. Kettenring, J. R. (1971). Canonical analysis of several sets of variables. Biometrika, 58(3), 433–451.
3. Sengupta, A. (1983). Generalized Canonical Variables. Encyclopedia Of Statistical Sciences.
4. Coelho, C. A. (1992). Generalized Canonical Analysis (PhD thesis).
5. Horst, P. (1961). Generalized canonical correlations and their applications to experimental data. Journal Of Clinical Psychology, 17(4).
6. Kakade, S. M., & Foster, D. P. (2007). Multi-view regression via canonical correlation analysis. In Learning Theory. Springer.
7. Sridharan, K., & Kakade, S. M. (2008). An Information Theoretic Framework for Multi-view Learning. In Proceedings of COLT. | {"extraction_info": {"found_math": true, "script_math_tex": 4, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 2, "equation": 2, "x-ck12": 0, "texerror": 0, "math_score": 0.8876586556434631, "perplexity": 676.6647384300474}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2017-51/segments/1512948597585.99/warc/CC-MAIN-20171217210620-20171217232620-00771.warc.gz"} |
https://meangreenmath.com/2013/06/16/student-misconceptions-about-pemdas/ | Simplify $6/2*(1+2)$.
A Common Incorrect Answer. According to PEMDAS, we should handle the parentheses first. So $6/2*(1+2) = 6/2*3$. Next, there are no exponents, so we should proceed to multiplication. So $6/2*3 = 6/(2*3) = 6/6$. Finally, we move to division, and we obtain the answer $6/6 =1$.
The above answer is incorrect and (even worse) arises from a natural but unfortunate misconception of the way that children are commonly taught order of operations. If you don’t see the misconception, please give it some thought before continuing.
The mnemonic PEMDAS, commonly taught in the United States, stands for
Parentheses
Exponents
Multiplication
Division
Subtraction
I personally never learned this memorization trick when I was in school. What I do remember, from learning BASIC computer programming around 1980, was the mnemonic My Dear Aunt Sally. I’m told that in the United Kingdom (and perhaps elsewhere in the English-speaking world) schoolchildren are taught BIMDAS, where B stands for Brackets and I stands for Indices.
Unfortunately, all of these memorization devices suffer from a common flaw: they do not indicate that multiplication and divison have equal precedence, and that addition and subtraction have equal precedence. In other words, the order of operations really are
Parentheses
Exponents
Multiplication and Divison (left to right)
Addition and Subtraction (left to right)
Therefore, the correct answer to the above problem is
$6/2*(1+2) = 6/2*3 = (6/2)*3 = 3*3 = 9$.
In brief, though not intended by teachers, PEMDAS and BIMDAS perhaps promote the misconception that multiplication takes precedence over division and addition takes precedence over subtraction. To avoid this misconception, one of my colleagues suggests that PEMDAS be taught more visually as
P
E
MD
AS
so that students will have a better chance of remembering that MD and AS should have equal precedence.
Next Post | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 5, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.7965560555458069, "perplexity": 1309.7713352272262}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2018-51/segments/1544376823565.27/warc/CC-MAIN-20181211040413-20181211061913-00604.warc.gz"} |
https://blog.xaviermaso.com/2018/05/31/Google-Hangouts-with-Irssi-on-NixOS.html | #### 31 May 2018
As I wanted to have access to Google Hangouts chats with Irssi on NixOS, here is a write-up of how I got it working.
## The protagonists
After a quick research using my favorite search engine DuckDuckGo, it turns out that we will need to add two piece of software to Irssi.
• BitlBee: an IRC gateway that act as a server your client connects to, using the IRC protocol ; and “translates” what you send and receive to another protocol (depending on whom your gateway connects to)
• purple-hangouts: a library “to support the proprietary protocol that Google uses for its Hangouts service”
## Add them to the system
We are pretty lucky as packages for BitlBee and purple-hangout are available on NixOS.
However, purple is not a plugin installed by default in the bitlbee package: we need to declare that we want it enabled.
Having a look at the declaration of bitlbee, we can find out the name of the relevant build option.
Let’s edit /etc/nixos/configuration.nix:
environment.systemPackages = with pkgs; [
[...]
bitlbee
purple-hangouts
[...]
];
nixpkgs.config.bitlbee.enableLibPurple = true;
services.bitlbee = {
enable = true;
libpurple_plugins = [ pkgs.purple-hangout ];
};
You can see how this fit my whole configuration on my GitHub repo.
Then rebuild the system:
sudo nixos-rebuild switch
## Try it out
See how it goes: start irssi, then type the following commands:
<@pamplemousse> /connect localhost
<@pamplemousse> /join &bitlbee
At this point, I need to create an account to identify myself to the BitlBee server.
<@pamplemousse> register StrongPasswordGeneratedWithKeepassXC
And verify our the plugin to communicate with Google Hangouts is present:
<@pamplemousse> plugins
[...]
<@root> Enabled Protocols: aim, bonjour, gg, hangouts, icq, identica, irc, jabber, novell, oscar, simple, twitter, zephysr
All good!
<@pamplemousse> account add hangouts MyAddress@Email.Com
<@pamplemousse> acc hangouts on
The next step is one of the most unreliable thing I have ever done to configure an account.
In fact, the previous command created another Irssi window to interact with the lib (that is, a private conversation with purple_request_0).
Follow the instruction that appeared there, and reply the oauth code that you obtain in the conversation (took me 30 minutes to figure this out).
Once that’s done, you should see all your contacts appearing in the &bitlbee window.
## Try it out
We can now start 1-on-1 conversations, for example with JohnDoe:
<@pamplemousse> /msg JohnDoe hello
And even join group chats (that exists):
<@pamplemousse> help chat list
<@pamplemousse> chat list hangouts
<@pamplemousse> chat add hangouts !1 #chatname
So later on, we can use the shortcut #chatname:
<@pamplemousse> /j #chatname | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.15548935532569885, "perplexity": 9336.94569062942}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 20, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2021-43/segments/1634323585265.67/warc/CC-MAIN-20211019105138-20211019135138-00670.warc.gz"} |
https://quant.stackexchange.com/questions/39323/funded-equity-collars-and-margin-loans | # Funded equity collars and margin loans
There is an article in the Financial Times today concerning equity funded collars [1]. The equity collar structure is used by a counterparty $A$ which wants to build up a position in a stock $S_t$. Let $B$ be the investment bank arranging the transaction, then the structure is as follows:
• $A$ enters into an equity collar with $B$ on shares $S_t$, i.e. $B$ sells a put with strike $k$ to $A$ and buys a call with strike $(k+\varepsilon)$ from them;
• Given the collar has positive delta to $B$ (short put + long call), to delta-hedge it the bank borrows stock $S_t$ which it then sells to $A$.
Another way for $A$ to build a position in the stock would be a margin loan, in which $A$ buys stock $S_t$ with a loan from $B$ which is collateralized by the bought stock (i.e. a repo-like transaction). Cash margin calls ensue if the stock price starts falling below predefined levels.
Now, the article claims that
[...] banks like [collars] because instead of taking on the credit risk of the borrower [as in a margin loan] , they take on the market risk of the underlying stock, which they can hedge as the share price fluctuates.
I understand the delta-hedge on the collar is imperfect (partial hedge, discrete rebalancing) plus there is gamma exposure, hence I understand the market risk coming from the collar structure (although it could be argued a margin loan also has market risk given it is collateralized by the stock). I also understand the credit/counterparty risk coming from the margin loan transaction, as a counterparty defaulting in the midst of a fast depreciation of the stock would leave the bank exposed to the gap between the latest margin call and the value of the stock collateral.
However I struggle to understand why there is no credit/counterparty risk in the collar structure. Can anybody explain?
There is no credit risk because the client pledges the underlying shares as collateral to the funded collar. This is not explained in the article.
The structure is built in such a way that the value of the loan + derivative package is always less than the value of the shares.
This can be done by for example lending an amount equal to the discounted put strike minus the initial cost of the collar (minus bank pnl).
The counterparty credit risk disappears and the bank can concern itself solely with the risk management of the position wrt market risk factors.
• what loan are you referring to? – Daneel Olivaw Apr 19 '18 at 9:32
• The payoff to the client of the collar combined with the share can be written: $\Phi(S_T)=k1_{\{S_T<k\}}+S_T1_{\{k\leq S_T \leq k+\varepsilon\}}+(k+\varepsilon)1_{\{k+\varepsilon<S_T\}}$ thus it is always positive, meaning that the bank will never have positive exposure and hence any counterparty risk. – Daneel Olivaw Apr 19 '18 at 9:37
• The structure is a funded collar ie loan + collar. – Ivan Apr 19 '18 at 13:52 | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.6219321489334106, "perplexity": 1688.7219628725436}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2019-26/segments/1560627999482.38/warc/CC-MAIN-20190624104413-20190624130413-00287.warc.gz"} |
https://tug.org/pipermail/xetex/2006-January/003037.html | [XeTeX] Howto "mark" languages / BiBTeX / and more :-)
Bruno Voisin bvoisin at mac.com
Wed Jan 18 12:53:20 CET 2006
Le 18 janv. 06 à 12:39, Martin Henning a écrit :
> if i import one of the babel packages, it will be used globally for
> the document, but how do i import more than one and use them on
> different 'marked' parts of the document?
Among several possibilities:
\documentclass[a4paper]{scrartcl}
\usepackage[english,german,russian]{babel}
\begin{document}
\selectlanguage{russian} % superfluous, last one in the above list
used by default
blah blah
\selectlanguage{german}
blah blah \foreignlanguage{english}{some text with English
hyphenation and style rules}
\end{document}
See /Library/teTeX/share/texmf.tetex/doc/generic/babel/user.dvi or,
even better, <ftp://ftp.cam.ctan.org/tex-archive/macros/latex/
required/babel/babel.pdf> which contains useful info, excluded from
user.dvi, on the specifics of each language setting.
And don't forget to select all the appropriate languages in the
corresponding stage when installing and configuring the TeX i-Package
(Expert mode possibly required).
Bruno Voisin | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8653687834739685, "perplexity": 24570.281738239242}, "config": {"markdown_headings": false, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2021-17/segments/1618039476006.77/warc/CC-MAIN-20210420152755-20210420182755-00214.warc.gz"} |
http://mathhelpforum.com/advanced-statistics/90979-probability-ruin-matrix-what-s-formula.html | # Math Help - The Probability of Ruin Matrix - Whats the formula?
1. ## The Probability of Ruin Matrix - Whats the formula?
Hello everyone,
I was not sure if this is an advanced topic, but since nobody has been able to answer me earlier I take my chances
I found the following table in one of my books on finance and trading. The author does not mention where he got it and I do not believe he has made it himself. Still, I cant find much info about it on the internet. Here goes:
Profit/Loss Ratio - P/R
Winning Percentage - % Win
[html] % winner
P/R 30% 40% 50% 60%
__________________________________
1:1 99 88 50 12
2:1 74 14 2 0
3:1 23 5 1 0
4:1 14 5 1 0
[/html]
* Ruin is defined as a 50% drawdown from starting equity
* The matrix assumes 100 trades executed for the same reason.
I understand the table this way:
Lets say we have 40% winners/60% losers and a profit/loss ratio of 2:1. This gives us a 14% probability of ruin. That is, a 14% probability that all the 60 losing trades come successively.
Could anyone please explain to me how this is calculated?
I am making a sheet in excel where I want to experiment with different variables (initial account size in trading account, average size of winners/losers, different profit/loss ratios) and see how it affects the probability of ruin.
Obviously, if the matrix above were to account for different account sizes, the average loser (in dollar) had to be adjusted so that the size of the total loss amounted to a 50% drawdown after 60 trades.
Example:
If we have a $5000 account, drawdown would occur if we had 60 losers in a row with an average loss of$41.67.
With a $10,000 account, this would only lead to a drawdown of 25%. Thus, the average loss would have to be increased to$83.33 if we were to use the matrix.
Also, Im not sure if I understand how in the matrix the different profit/loss ratios affect the probability of ruin, since the loss is constant (1 dollar for example).
I hope someone is able to follow my thoughts
My understanding of probabilities is very weak and Im not sure if Im even communicating correctly what I want to know.
Thanks very much in advance to anyone who has some clues or help to provide.
Best regards,
Hello everyone,
I was not sure if this is an advanced topic, but since nobody has been able to answer me earlier I take my chances
I found the following table in one of my books on finance and trading. The author does not mention where he got it and I do not believe he has made it himself. Still, I cant find much info about it on the internet. Here goes:
Profit/Loss Ratio - P/R
Winning Percentage - % Win
[html] % winner
P/R 30% 40% 50% 60%
__________________________________
1:1 99 88 50 12
2:1 74 14 2 0
3:1 23 5 1 0
4:1 14 5 1 0
[/html]* Ruin is defined as a 50% drawdown from starting equity
* The matrix assumes 100 trades executed for the same reason.
I understand the table this way:
Lets say we have 40% winners/60% losers and a profit/loss ratio of 2:1. This gives us a 14% probability of ruin. That is, a 14% probability that all the 60 losing trades come successively.
Could anyone please explain to me how this is calculated?
Hi,
Using google I found this book. I guess this is the one you're refering to?
One thing is for sure: the starting equity must be given, otherwise it makes no sense. That makes me think the author did probably not get this table himself, indeed.
I did a few tests and it seems that it should be between $15 and$20, but (oddly enough) the values in the matrix don't match exactly or even very closely for any initial account.
Anyway, here's what the table should mean: (for instance, for the value "2:1, 60%", and assuming the initial equity is $20) Starting with an initial$20, we perform 100 trades successively, each of which can be a winner (with probability 60%), meaning that we win $2, or a loss (with probability 40%), meaning that we lose$1. During the sequence of trades, our account fluctuates, it may even become negative. The table tell that, with probability 14%, at some time we will have less than $10 in our account. If instead you start with$50, you would have to redo the whole table.
I don't think there's a formula for the values of the table. They were certainly obtained by doing computer simulations. The idea is the following: you make a program that performs lots (thousands) of random sequences of 100 trades (each of which is a win with some given probability, like 60%), and you make it compute the proportion of sequences where ruin happens (i.e. at some time between 1 and 100, the equality goes below 50% of the initial value).
I don't know if such simulations can be done with Excel. I did it with Scilab (a free program for numeric computations), but you could use any programming langage (or a programmable calculator).
3. Hello Laurent,
Thanks for writing
What if we say that the initial account is $100 and the risk per trade is a constant$1 dollar? Would that change anything?
Dont you think it is possible to deduct a formula out of this matrix?
I do however agree with you that it is very likely that the numbers are made from a simulation.
Either way, I am interpreting the matrix wrong in my initial thread?
It is not a 14% probability that we would get 60 losers in a row (I thought the way the author wrote made it sound like that), but a 14% probability that during the 100 trades we would experience drawdown (less than 50% of initial equity)?
Thanks very much in advance Laurent.
I`ll check out Scilab, if I understand anything of it
All the best,
Originally Posted by Laurent
Hi,
Using google I found this book. I guess this is the one you're refering to?
One thing is for sure: the starting equity must be given, otherwise it makes no sense. That makes me think the author did probably not get this table himself, indeed.
I did a few tests and it seems that it should be between $15 and$20, but (oddly enough) the values in the matrix don't match exactly or even very closely for any initial account.
Anyway, here's what the table should mean: (for instance, for the value "2:1, 60%", and assuming the initial equity is $20) Starting with an initial$20, we perform 100 trades successively, each of which can be a winner (with probability 60%), meaning that we win $2, or a loss (with probability 40%), meaning that we lose$1. During the sequence of trades, our account fluctuates, it may even become negative. The table tell that, with probability 14%, at some time we will have less than $10 in our account. If instead you start with$50, you would have to redo the whole table.
I don't think there's a formula for the values of the table. They were certainly obtained by doing computer simulations. The idea is the following: you make a program that performs lots (thousands) of random sequences of 100 trades (each of which is a win with some given probability, like 60%), and you make it compute the proportion of sequences where ruin happens (i.e. at some time between 1 and 100, the equality goes below 50% of the initial value).
I don't know if such simulations can be done with Excel. I did it with Scilab (a free program for numeric computations), but you could use any programming langage (or a programmable calculator). | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8752860426902771, "perplexity": 699.0097999058972}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2014-23/segments/1405997902579.5/warc/CC-MAIN-20140722025822-00088-ip-10-33-131-23.ec2.internal.warc.gz"} |
https://chadrick-kwag.net/python-implementation-of-rotating-caliper-algorithm/ | Rotating caliper algorithm is used to find a rectangle that fits a convex hull. Below is a python implementation that finds all rotated rectangles for a given convex hull points. It is up to the user to select which rectangle to use since it returns all possible rotating caliper rectangles.
import numpy as np
def get_rotating_caliper_bbox_list(hull_points_2d):
"""
hull_points_2d: array of hull points. each element should have [x,y] format
"""
# Compute edges (x2-x1,y2-y1)
edges = np.zeros( (len(hull_points_2d)-1,2) ) # empty 2 column array
for i in range( len(edges) ):
edge_x = hull_points_2d[i+1,0] - hull_points_2d[i,0]
edge_y = hull_points_2d[i+1,1] - hull_points_2d[i,1]
edges[i] = [edge_x,edge_y]
# Calculate edge angles atan2(y/x)
edge_angles = np.zeros( (len(edges)) ) # empty 1 column array
for i in range( len(edge_angles) ):
edge_angles[i] = np.arctan2( edges[i,1], edges[i,0] )
# Check for angles in 1st quadrant
for i in range( len(edge_angles) ):
edge_angles[i] = np.abs( edge_angles[i] % (np.pi/2) ) # want strictly positive answers
#print "Edge angles in 1st Quadrant: \n", edge_angles
# Remove duplicate angles
edge_angles = np.unique(edge_angles)
#print "Unique edge angles: \n", edge_angles
bbox_list=[]
for i in range( len(edge_angles) ):
# Create rotation matrix to shift points to baseline
# R = [ cos(theta) , cos(theta-PI/2)
# cos(theta+PI/2) , cos(theta) ]
R = np.array([ [ np.cos(edge_angles[i]), np.cos(edge_angles[i]-(np.pi/2)) ], [ np.cos(edge_angles[i]+(np.pi/2)), np.cos(edge_angles[i]) ] ])
# Apply this rotation to convex hull points
rot_points = np.dot(R, np.transpose(hull_points_2d) ) # 2x2 * 2xn
# Find min/max x,y points
min_x = np.nanmin(rot_points[0], axis=0)
max_x = np.nanmax(rot_points[0], axis=0)
min_y = np.nanmin(rot_points[1], axis=0)
max_y = np.nanmax(rot_points[1], axis=0)
# Calculate height/width/area of this bounding rectangle
width = max_x - min_x
height = max_y - min_y
area = width*height
# Calculate center point and restore to original coordinate system
center_x = (min_x + max_x)/2
center_y = (min_y + max_y)/2
center_point = np.dot( [ center_x, center_y ], R )
# Calculate corner points and restore to original coordinate system
corner_points = np.zeros( (4,2) ) # empty 2 column array
corner_points[0] = np.dot( [ max_x, min_y ], R )
corner_points[1] = np.dot( [ min_x, min_y ], R )
corner_points[2] = np.dot( [ min_x, max_y ], R )
corner_points[3] = np.dot( [ max_x, max_y ], R )
bbox_info = [edge_angles[i], area, width, height, min_x, max_x, min_y, max_y, corner_points, center_point]
bbox_list.append(bbox_info)
return bbox_list
this code was based on code from here. I only updated the code to return all possible rectangles instead of the one with minimum area since the user may be interested in other rectangles depending on their needs. Also I’ve updated it to use explicit functions from numpy.
Categories: algorithmpython | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.18325965106487274, "perplexity": 24758.051128488103}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2021-21/segments/1620243988802.93/warc/CC-MAIN-20210507181103-20210507211103-00524.warc.gz"} |
https://www.ejilt.org/archive/view_article?pid=jilt-7-1-107 | ARTICLE
# Logistics lean integration strategies: case study of Samsung Electronics LCD inbound logistics
Jee Young Suh*, Yong Jin Kim**,*
*Graduate Student, Inha University, 253 Yonghyun-dong, Nam-Ku Incheon 402-751, Korea. E-mail: jysuh@logisall.co.kr
**Assistant Professor, Asia Pacific School of Logistics, Inha University, 253 Yonghyundong, Nam-Ku Incheon 402-751, Korea. E-mail: yongjin@inha.ac.kr.
*Corresponding Author, Assistant Professor, Asia Pacific School of Logistics, Inha University, 253 Yonghyundong, Nam-Ku Incheon 402-751, Korea. E-mail: yongjin@inha.ac.kr.
© Copyright 2009 Jungseok Research Institute of International Logistics and Trade. This is an Open-Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/4.0/) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.
Received: Apr 17, 2009; Revised: Jun 01, 2009; Accepted: Jun 01, 2009
Published Online: Jun 30, 2009
## Abstract
The electronics industry is a key industry in South Korea. To improve efficiency and maintain a competitive edge in fast-paced technological age it is critical to synchronize production supply with market demand. This paper focuses on the strategies which make the “just in time” production system within the electronic supply chain. The presented case study of Samsung Electronics Thin Film Transistor-Liquid Crystal Display (TFT-LCD) Inbound Logistics provides a solid example of process integration in the areas of: packaging, transportation and information sharing. The problems faced by Samsung Electronics in the early 2000‘s were a direct result of an imbalance between increased traffic/demand and existing production capacity. The most detrimental of these problems caused delays in supply, shortage of space in the hub center and the bottlenecking of supply transportation. This paper demonstrates how Samsung Electronics reexamined and systematically streamlined their existing processes and how they successfully integrated “lean thinking” strategies to all areas of TFT-LCD production. As a result of the integration of these strategies, Samsung Electronics began using a line-to-line packing system which focused on packing items in a group using a standardized, returnable packing system. Additionally, they opted to replace their paper invoice system for an improved transportation system through which a data could reflect flows of information and materials in real time. The integration of these strategies gave Samsung Electronics a new approach to TFT-LCD Inbound Logistics which allowed them to overcome their dilemmas and resulted in successful outcomes, decreased lead times, higher quality products and an reduction in total costs.
Keywords: TFT-LCD; Lean strategies; line-to-line packing system; case study; Samsung electronics
## 1. Introduction
1.1 Display electronics industry environment
Display electronics and multimedia are industries that work hand-in-hand, each driving the other either to success or failure. One such example is the recent increased customer demand in notebook computers which is a direct result in the increased popularity of wireless/LAN networks. To accommodate for specific customer multimedia demands (lightweight yet with clear display capability) TFT-LCDs became the main type of display product selected by the industry. The main components of all basic display units include: (a) liquid glass plate(s), an IC circuit system and a backlight unit. In these basic units, liquid glass plates are made through a TFT process which includes a color filtering and cell process. However, the enhanced processing of producing TFT-LCDs includes the injection of a semi-liquid material between two glass plates and uses an optic anisotropic process to indicate image information by controlling the amount of light which passes through the semi-liquid material. These changes allow TFT-LCDs to maintain a higher quality of image stabilization while also increasing the ease of handing and precision during processing.
1995 was the first year during which TFT-LCDs were mass produced. It was at this time that many Korean electronics companies made the decision to allow large scale investing in the production of these innovative and impressive screens. In 2007 alone, the export revenue generated by this new technology reached a record breaking $38.5M. This meant that 38% of Korea’s global market share for that year was produced by its display industry. Currently, the display industry is among the 3 major exporting industries found in Korea. This trend has sparked worldwide competition which continues to push the increasing popularity of this industry. For example, North American and European companies (which have patents on display materials, technology or equipments) are constantly focusing on the research and development of newer and more advanced technology so that they may remain competitive. While Japanese companies (which have the largest capacity for the production of metal and equipment) discuss possible mergers with other Japanese companies in order to protect their dominance in this arena. Furthermore, Taiwanese companies (which target Korean companies as their industry rival) choose to follow the strategies of other countries while making enhancements where possible. Although China has only recently caught on to the trend, many of those who recognize the industry’s potential have also started to develop TFT-LCD production line systems. 1.2 Overview of the company Since 2001 Samsung Electronics has held the #1 ranking position for maintaining the highest percentage (roughly 20%) of the global market share. However, as the market for TFT-LCDs grows and gives way to new and more aggressive competition, there is a consistent need for Samsung to keep ahead of new technologies while maintaining the demand for reasonable pricing. Table 1. Ranking of the display companies in revenue ranking LCD PDP company Revenue ($100 M) Market share company Revenue (\$ 100 M) market share
1 Samsung 183.5 19.5% Matushita 20.8 36.1%
2 LG display 153.1 16.3% SDI 14.9 26.0%
3 AUO 152.7 16.2% LG 14.0 24.3%
4 SHARP 91 9.7% others 7.8 13.7%
Source: The 9th seminar of forecasting in the electronic industry, electronic component research, 2008.5
Samsung Electronics has four production sites based in various locations throughout Korea and China. In Korea 3 sites, ‘Ki-Heung’ houses the production of mobile displays, ‘Cheonan’ maintains PC and notebook LCD production and finally large TV LCDs are manufactured in ‘Tang Jung’. For the production of medium sized LCD modules, SoJu of China was selected.
As the size of the LCD panel production became bigger and the market demand kept growing, some of serious problems have arisen. The problems were mainly about imbalance with increased traffic and existing capacity such as delay in supply due to the excessive process, shortage of space in the hub center due to keeping increased safe stocks, bottleneck of supply transportation. This problem situation is described in the aspects of packaging process, working force and warehouse, transportation and information system.
## 2. Problem description
2.1 Packaging process
The majority of materials used in the primary supply packaging process were boxes made of danplate or corrugated cardboard. Basically, the components produced by each of the suppliers were packed independently or ‘case by case’. Afterward, they were loaded onto pallets along with piling up and wrapping. After the individual packaging, the components were moved into hub center where the exterior packaging was removed. The items where then classified and stored while waiting to be added to the assembly line (stand by). The packaging dimensions were various and complex. For example, there are 65 types of danaplate module units which were designed for packaging the back light units and 42 types which were designed for packaging the top chassis. Because of the low standardization of packaging, the carrying efficiency rate of these boxes (with respect to their capacity) was only 47.1%. The packaging boxes were only designed to protect individual materials. Sometimes even the same materials with the same dimensions were packaged by each individual supplier using disposable materials and a different module unit.
Table 2. Previous handling process from supplier to assembly line
Place Numbers of steps Process
Supplier 20 Inner packing (by individual module)
Transportation 3 moving separately
Hub center 10 Stored (3~5 days)
Material warehouse 6 Moving separately and stored
KIT 8 Moving separately and stored
Unpacking 4 Unpacking by workers
Transportation 5 Shipping in the cart
JIT 5 Stand by
Assembly line 2 Assembly components to make LCD panels
In order to prepare the components for the assembly line, while maintaining high levels of material quality and cleanliness, employees were required to carry out a highly involved process which includes handling the materials individually. This process included many steps which were not limited to: packaging, moving, unpacking, sampling, repacking the materials and performing regularly quality checks. Due to their disposable nature, other materials such as packaging in danplate or corrugated paper required additional handling to protect them from damage or contamination. In particular, these materials required the use of additional sub packaging materials such as filling cushion materials.
2.2 Working force and warehouse
At the time of this paper, the number of employees working for the Samsung LCD production line (including the employees of whole suppliers) was approximately 1.7M. Among them, the number of workers involved with the packaging process was about 6,000. The existing packaging processes contained repetitive tasks which required intensive labor and time. In addition, excessive and repetitive packaging increased the risk of component damage and/or contamination. The existing system for material warehousing was composed of hub center and material storage. The storage area was divided as follows: 39,762m2 for shipment in the KIT room, 95, 700 m2 for third party or partner company work space and 19,800 m2 for operating deposit. It is projected that as production traffic grows the area required will rapidly exceed the existing space allotted.
2.3 Transportation and information system
Each supplier used an individual transportation system based on their delivery order. The materials would then be stored in the hub center and/or the material warehouse as stock for 3~7 days. Then, before inputting the materials into the assembly line, they would then be placed in “stand-by” for 1~2 days. Due to the various modules of packaging units, the loading efficiency rate was approximately 47%. This low efficiency rate, eventually led to increased transportation and storage costs. It was impossible to carry 2 loading layers in the truck. The operating cost of hub center was 300M won per year. Order and delivery data was managed by a paper invoice checking system which could be incorrect due to human error. This paper checking system could not provide real time information. Therefore, it was difficult to link real time material flows with the LCD components supply chain.
## 3. Lean strategies
The conventional method was independent and individual packaging. The lean approach for process integration focused on two target issues: one was the standardization of packaging and the other was the integration of the transportation system and information. The solution for packaging was to implement a line-to-line supply chain using standard packaging tools. The integration of the transportation required an allocation of a new transportation mode so that real time data could meet the real time flows of materials.
3.1 Standardization of packaging
Table 3. Integration of packaging process
AS-IS TO-BE
Packaging process inner packaging putting in the tray
outer packaging putting in the cart
palletizing wrapping
wrapping un-wrapping
un-wrapping assembly line
putting in the danplate box
outer un-packing
inner unpacking
putting in the cart
assembly line
First of all, it is important to find standard packaging module by grouping according to the common dimension or similar shape. Next, based on the module unit, the lean approach for packaging system is made. The system is composed of standardized containers such as trays and carts. Trays replaced inner packaging, while carts replaced outer packaging. This tray & cart packaging system made line-to line (direct supply) possible. Standard packaging system increased carrying efficiency rate and made it possible that suppliers could use containers repeatedly and collectively. Reduction of packaging steps from 10 steps to 5 steps meant rapid handling, less work force, easy to keep product’s quality and cleanliness.
Figure 1. Reusable packaging containers designed for LCD module unit
In addition to the above improvements, the implementation of standardization also reduced and streamlined the packaging of BLU (Back Light Unit) and T/C(Top Chassis) and increased the carrying efficiency rate from 47% to 89%.
3.2 Integration of transportation system
Another strategy used by Samsung Electronics was to move the transportation system from a process involving individual supply transport to one that used a ‘milk-run’ or collective allocation transport system. They also implemented an integrated information system which included the automatic scheduling of allocation and real time PDA tracking which allowed real time data to reflect and meet the real time flow of materials. The integration of these steps allowed room for two key improvements in the transportation system.
Figure 2. Integration of transport system
Primarily, the system integration reduced the dependency on expert drivers so that general drivers could accomplish the same tasks with similar efficiency. Secondarily, the use of TMS (Transportation Management System) improved visibility and communication between drivers and dispatchers which increased the ability to respond to sudden needs of shippers and reduced the possibility of potential problems while increasing shipper satisfaction.
Figure 3. TMS operating process
## 4. Lean strategies achievements
4.1 Quantitative effects
As shown in the following table, due to the improved standardization process, the types of packaging modules were reduced by 96% and the steps involved in packaging and handling were reduced by 45%. Also, the number of employees required to support the handling process was reduced by 50%. As a result, the packaging costs were reduced by 64%. The integrated transportation system reduced the lead time from order to delivery by 70% which reduced the area used by the warehousing of good to be reduced by 76%. Finally, the number trucks required to deliver the goods was reduced by 41%.
Figure 4. Quantitative effects
4.2 Qualitative effects
As this example shows, Samsung Electronics was able to use ‘lean strategies’ such as the standardization of packaging and integration of transportation systems to regain control and efficiency by matching their production capacity with supplier transportation capacity. This integration focused on producing the right amount product at the right time with less cost which allowed both the suppliers and Samsung to share the utilization of packaging modules which allowed both to increase their buying power through a cooperative buying approach. Furthermore, it became possible for suppliers to share material information in real time. As a result, Samsung Electronics was able to produce LCD final panels in 3 days.
## 5. Conclusion
This research analyzed the methodology of process integration as it relates to: packaging, transportation and information. Samsung Electronics examined their previously existing processes from a logistical point of view. They then applied ‘lean strategies’ to all areas of the integration process to allow for a successful transition. Consequently, they turned away from using an individual packing and unpacking system and began using a line-to-line system which focused on a standardized, returnable packaging process. They also improved their conventional paper invoice transportation system such that it became an integrated process which could reflect actual flows of materials in real time. This approach allowed Samsung Electronics to decrease the amount of lead time and provide a guarantee of higher quality products while reducing their overall costs. Through the implementation and integration of these ‘lean strategies’; Samsung Electronics is now able to maintain a dominant/leader ship position in many global markets. This is directly a result of the company’s ability to streamline and improve their supply chain system in the area of LCD production advancing their production supply to meet market demand in only 3 day’s time.
## Acknowledgment
This work was supported by the Korea Research Foundation Grant funded by the Korean Government(MOEHRD) (KRF-2008-005-J01601).
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##### Call for Paper: Special Issue
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I don't want to open this window for a day. | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.2874782979488373, "perplexity": 5692.5981876663}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2021-25/segments/1623487611641.26/warc/CC-MAIN-20210614074543-20210614104543-00212.warc.gz"} |
http://www.chegg.com/homework-help/questions-and-answers/25-source-applied-uncharged-16capacitor-shown-figure-1-determine-capacitor-voltage--2-dete-q3066134 | At, a 2.5-source is applied to an uncharged 1.6capacitor as shown in the figure.
1)Determine the capacitor voltage,at.
2)Determine the energy,, stored in the capacitor at. | {"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8673248291015625, "perplexity": 5701.66622768876}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2016-26/segments/1466783393332.57/warc/CC-MAIN-20160624154953-00131-ip-10-164-35-72.ec2.internal.warc.gz"} |
https://www.physicsforums.com/threads/calculating-voltmeter-resistance-in-dc-circuit.861013/ | # Calculating voltmeter resistance in DC circuit
Tags:
1. Mar 7, 2016
### ztalira
1. The problem statement, all variables and given/known data
initial problem: A 228 −Ω resistor and a 586 −Ω resistor are connected in series across a 90.0−V line.
A voltmeter connected across the 228 −Ω resistor reads 24.0 V . Find the voltmeter resistance.
For Req, i got Req=228R/(2+228), R being the resistance of the voltmeter.
But after that, I'm stuck. How do I find the necessary I(current) in order to calculate the R (resistance of voltmeter).?
2. Relevant equations
V=IR
1/Req=1/R1 +1/R2
3. The attempt at a solution
For Req, i got Req=228R/(2+228), R being the resistance of the voltmeter.
But after that, I'm stuck. How do I find the necessary I(current) in order to calculate the R (resistance of voltmeter).?
2. Mar 7, 2016
### RedDelicious
The total current is going to be given by V = IR
They give you the total voltage and they give you the resistors. To find the total resistance you have to find the equivalent resistance. The resistors are connected in series, not in parallel, so what does that tell you about how to calculate the equivalent resistance?
Once you solve for the equivalent resistance and find the total current, you can use Ohm's law again and find the resistance with the voltmeter. The resistance of the voltmeter itself will then be the difference between the value of the resistance with it and the value without it.
3. Mar 7, 2016
### drvrm
normally a voltmeter does not disturb a circuit parameters - but suppose it draws a current say( Iv) then the current in 228 ohm resistance will be reduced by Iv so you have two loops one smaller one through voltmeterand the 228 ohm. a larger loop is current flowing through the two resistances- one can apply Kirchhoff's loop equations to relatecurrent and voltage and resistances. that should solve your problem
4. Mar 7, 2016
5. Mar 7, 2016
### BananaChris
The first calculation is simply a voltage divider where you can determine the resulting resistance after puting the voltmeter across R1 => Rx.
Then take Rx and calculate back using the formula you use when you have two resistors in paralell and wanna know the total resistance.
you don't need a current to find Rv.
except you have to calculate them. then just use the total resistance without the voltmeter and then with the voltmeter...where R1 changes to Rx.
br Chris | {"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8712406754493713, "perplexity": 995.3142548295007}, "config": {"markdown_headings": true, "markdown_code": false, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 20, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2017-51/segments/1512948523222.39/warc/CC-MAIN-20171213123757-20171213143757-00304.warc.gz"} |
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These functions preserve the $\mathbf{L}^2$ norm under warping and are ideally suited for simultaneous estimation of regression and warping parameters. Using both simulated and real-world data sets, we demonstrate our approach and evaluate its prediction performance relative to current models. In addition, we propose an extension to functional logistic and multinomial logistic regression Elastic Net Regularization In statistics and, in particular, in the fitting of linear or logistic regression models, the elastic net is a regularized regression method that linearly combines the L1 and L2 penalties of the lasso and ridge methods. Elasticsearch Elasticsearch is a search server based on Lucene. It provides a distributed, multitenant-capable full-text search engine with a RESTful web interface and schema-free JSON documents. Elasticsearch is developed in Java and is released as open source under the terms of the Apache License. Elasticsearch is the second most popular enterprise search engine. Elasticsearch, Logstash and Kibana(ELK Stack) ELK stands for Elasticsearch, Logstash and Kibana. Brief definitions: Logstash: It is a tool for managing events and logs. You can use it to collect logs, parse them, and store them for later use (like, for searching). Speaking of searching, logstash comes with a web interface for searching and drilling into all of your logs. It is fully free and fully open source. Elasticsearch: Elasticsearch is a search server based on Lucene. It provides a distributed, multitenant-capable full-text search engine with a RESTful web interface and schema-free JSON documents. Kibana: A nifty tool to visualize logs and timestamped data. Eligibility Traces Eligibility traces are one of the basic mechanisms of reinforcement learning. For example, in the popular TD(lambda) algorithm, the lambda refers to the use of an eligibility trace. Almost any temporal-difference (TD) method, such as Q-learning or Sarsa, can be combined with eligibility traces to obtain a more general method that may learn more efficiently. There are two ways to view eligibility traces. The more theoretical view, which we emphasize here, is that they are a bridge from TD to Monte Carlo methods. When TD methods are augmented with eligibility traces, they produce a family of methods spanning a spectrum that has Monte Carlo methods at one end and one-step TD methods at the other. In between are intermediate methods that are often better than either extreme method. In this sense eligibility traces unify TD and Monte Carlo methods in a valuable and revealing way. The other way to view eligibility traces is more mechanistic. From this perspective, an eligibility trace is a temporary record of the occurrence of an event, such as the visiting of a state or the taking of an action. The trace marks the memory parameters associated with the event as eligible for undergoing learning changes. When a TD error occurs, only the eligible states or actions are assigned credit or blame for the error. Thus, eligibility traces help bridge the gap between events and training information. Like TD methods themselves, eligibility traces are a basic mechanism for temporal credit assignment. ELimination Et Choix Traduisant la REalité(ELECTRE) ELECTRE is a family of multi-criteria decision analysis methods that originated in Europe in the mid-1960s. The acronym ELECTRE stands for: ELimination Et Choix Traduisant la REalité (ELimination and Choice Expressing REality). The method was first proposed by Bernard Roy and his colleagues at SEMA consultancy company. A team at SEMA was working on the concrete, multiple criteria, real-world problem of how firms could decide on new activities and had encountered problems using a weighted sum technique. Bernard Roy was called in as a consultant and the group devised the ELECTRE method. As it was first applied in 1965, the ELECTRE method was to choose the best action(s) from a given set of actions, but it was soon applied to three main problems: choosing, ranking and sorting. The method became more widely known when a paper by B. Roy appeared in a French operations research journal. It evolved into ELECTRE I (electre one) and the evolutions have continued with ELECTRE II, ELECTRE III, ELECTRE IV, ELECTRE IS and ELECTRE TRI (electre tree), to mention a few. Bernard Roy is widely recognized as the father of the ELECTRE method, which was one of the earliest approaches in what is sometimes known as the French School of decision making. It is usually classified as an “outranking method” of decision making. There are two main parts to an ELECTRE application: first, the construction of one or several outranking relations, which aims at comparing in a comprehensive way each pair of actions; second, an exploitation procedure that elaborates on the recommendations obtained in the first phase. The nature of the recommendation depends on the problem being addressed: choosing, ranking or sorting. Usually the Electre Methods are used to discard some alternatives to the problem, which are unacceptable. After that we can use another MCDA to select the best one. The Advantage of using the Electre Methods before is that we can apply another MCDA with a restricted set of alternatives saving much time. Criteria in ELECTRE methods have two distinct sets of parameters: the importance coefficients and the veto thresholds. OutrankingTools Elite Based Guided Local Search(EB-GLS) Local search is a basic building block in memetic algorithms. Guided Local Search (GLS) can improve the efficiency of local search. By changing the guide function, GLS guides a local search to escape from locally optimal solutions and find better solutions. The key component of GLS is its penalizing mechanism which determines which feature is selected to penalize when the search is trapped in a locally optimal solution. The original GLS penalizing mechanism only makes use of the cost and the current penalty value of each feature. It is well known that many combinatorial optimization problems have a big valley structure, i.e., the better a solution is, the more the chance it is closer to a globally optimal solution. This paper proposes to use big valley structure assumption to improve the GLS penalizing mechanism. An improved GLS algorithm called Elite Biased GLS (EB-GLS) is proposed. EB-GLS records and maintains an elite solution as an estimate of the globally optimal solutions, and reduces the chance of penalizing the features in this solution. We have systematically tested the proposed algorithm on the symmetric traveling salesman problem. Experimental results show that EB-GLS is significantly better than GLS. ➘ “Guided Local Search” Ellipsoid Method for Linear Programming In this paper, ellipsoid method for linear programming is derived using only minimal knowledge of algebra and matrices. Unfortunately, most authors first describe the algorithm, then later prove its correctness, which requires a good knowledge of linear algebra. ELM with Local Connections(ELM-LC) This paper is concerned with the sparsification of the input-hidden weights of ELM (Extreme Learning Machine). For ordinary feedforward neural networks, the sparsification is usually done by introducing certain regularization technique into the learning process of the network. But this strategy can not be applied for ELM, since the input-hidden weights of ELM are supposed to be randomly chosen rather than to be learned. To this end, we propose a modified ELM, called ELM-LC (ELM with local connections), which is designed for the sparsification of the input-hidden weights as follows: The hidden nodes and the input nodes are divided respectively into several corresponding groups, and an input node group is fully connected with its corresponding hidden node group, but is not connected with any other hidden node group. As in the usual ELM, the hidden-input weights are randomly given, and the hidden-output weights are obtained through a least square learning. In the numerical simulations on some benchmark problems, the new ELM-CL behaves better than the traditional ELM. Elo Rating System The Elo rating system is a method for calculating the relative skill levels of players in competitor-versus-competitor games such as chess. It is named after its creator Arpad Elo, a Hungarian-born American physics professor. The Elo system was invented as an improved chess rating system and is also used in many other games. It has also been adapted for use as a rating system for multiplayer competition in a number of video games, and has been adapted to team sports including soccer (association football), American college football, basketball, Major League Baseball, competitive programming, and E-Sports. The difference in the ratings between two players serves as a predictor of the outcome of a match. Two players with equal ratings who play against each other multiple times are expected to score an equal number of wins. A player whose rating is 100 points greater than their opponent’s is expected to win 64% of the time; if the difference is 200 points, then the expected win proportion for the stronger player is 76%. E-MAML ➘ “Krazy World” Embedded-Graph In this paper, we propose a new type of graph, denoted as ’embedded-graph’, and its theory, which employs a distributed representation to describe the relations on the graph edges. Embedded-graphs can express linguistic and complicated relations, which cannot be expressed by the existing edge-graphs or weighted-graphs. We introduce the mathematical definition of embedded-graph, translation, edge distance, and graph similarity. We can transform an embedded-graph into a weighted-graph and a weighted-graph into an edge-graph by the translation method and by threshold calculation, respectively. The edge distance of an embedded-graph is a distance based on the components of a target vector, and it is calculated through cosine similarity with the target vector. The graph similarity is obtained considering the relations with linguistic complexity. In addition, we provide some examples and data structures for embedded-graphs in this paper. EML-NET In this work, we apply state-of-the-art Convolutional Neural Network(CNN) architectures for saliency prediction. Our results show that better saliency features can be delivered by a deeper CNN model. However, it is very space-consuming to apply a complex model due to the large size of input images. The space complexity becomes even more problematic when we extract features from multiple convolutional layers or different models. In this paper, we propose a modular saliency system which aims at splitting the whole network into small modules. The main difference in our approach s that the encoder and decoder can be separately trained for the scalability. Furthermore, the encoder can contain more than one CNN model to extract features and the models can have different architectures or pre-trained on different datasets. This parallel design allows us to better utilize the computational space in order to apply more powerful encoder. More importantly, our network can be easily expanded almost without extra spaces, other pre-trained CNN models can be combined for a wider range of visual knowledge. We denote our expandable multi-layer network as EML-NET in this paper. Our method is evaluated on three public saliency benchmarks, SALICON, MIT300 and CAT2000. The proposed EML-NET achieves state-of-the-art results on the metric of Normalized Scanpath Saliency using a modified loss function. Emotional Chatting Machine(EMC) Emotional intelligence is one of the key factors to the success of dialogue systems or conversational agents. In this paper, we propose Emotional Chatting Machine (ECM) which generates responses that are appropriate not only at the content level (relevant and grammatical) but also at the emotion level (consistent emotional expression). To the best of our knowledge, this is the first work that addresses the emotion factor in large-scale conversation generation. ECM addresses the factor in three ways: modeling high-level abstraction of emotion expression by embedding emotion categories, changing of implicit internal emotion states, and using explicit emotion expressions with an external emotion vocabulary. Experiments show that our model can generate responses appropriate not only in content but also in emotion. Emphatic Temporal-Difference Learning Algorithm(ETD) In this paper we present the first empirical study of the emphatic temporal-difference learning algorithm (ETD), comparing it with conventional temporal-difference learning, in particular, with linear TD(0), on on-policy and off-policy variations of the Mountain Car problem. The initial motivation for developing ETD was that it has good convergence properties under \emph{off}-policy training (Sutton, Mahmood \& White 2016), but it is also a new algorithm for the \emph{on}-policy case. In both our on-policy and off-policy experiments, we found that each method converged to a characteristic asymptotic level of error, with ETD better than TD(0). TD(0) achieved a still lower error level temporarily before falling back to its higher asymptote, whereas ETD never showed this kind of ‘bounce’. In the off-policy case (in which TD(0) is not guaranteed to converge), ETD was significantly slower. Empirical Bayes Geometric Mean(EBGM) Adjusted estimate for the relative reporting ratio. Example: if EBGM=3.9 for acetaminophen-hepatic failure, then this drug-event combination occurred in the data 3.9 times more frequently than expected under the assumption of no association between the drug and the event. openEBGM Empirical Bayes Matrix Factorization(EBMF) Matrix factorization methods – including Factor analysis (FA), and Principal Components Analysis (PCA) – are widely used for inferring and summarizing structure in multivariate data. Many matrix factorization methods exist, corresponding to different assumptions on the elements of the underlying matrix factors. For example, many recent methods use a penalty or prior distribution to achieve sparse representations (‘Sparse FA/PCA’). Here we introduce a general Empirical Bayes approach to matrix factorization (EBMF), whose key feature is that it uses the observed data to estimate prior distributions on matrix elements. We derive a correspondingly-general variational fitting algorithm, which reduces fitting EBMF to solving a simpler problem – the so-called ‘normal means’ problem. We implement this general algorithm, but focus particular attention on the use of sparsity-inducing priors that are uni-modal at 0. This yields a sparse EBMF approach – essentially a version of sparse FA/PCA – that automatically adapts the amount of sparsity to the data. We demonstrate the benefits of our approach through both numerical comparisons with competing methods and through analysis of data from the GTEx (Genotype Tissue Expression) project on genetic associations across 44 human tissues. In numerical comparisons EBMF often provides more accurate inferences than other methods. In the GTEx data, EBMF identifies interpretable structure that concords with known relationships among human tissues. Software implementing our approach is available at https://…/flashr. Empirical Equilibrium We introduce empirical equilibrium, the prediction in a game that selects the Nash equilibria that can be approximated by a sequence of payoff-monotone distributions, a well-documented proxy for empirically plausible behavior. Then, we reevaluate implementation theory based on this equilibrium concept. We show that in a partnership dissolution environment with complete information, two popular auctions that are essentially equivalent for the Nash equilibrium prediction, can be expected to differ in fundamental ways when they are operated. Besides the direct policy implications, two general consequences follow. First, a mechanism designer may not be constrained by typical invariance properties. Second, a mechanism designer who does not account for the empirical plausibility of equilibria may inadvertently design implicitly biased mechanisms. Empirical Likelihood(EL) Empirical likelihood (EL) is an estimation method in statistics. Empirical likelihood estimates require few assumptions about the error distribution compared to similar methods like maximum likelihood. EL can handle data well as long as it is independent and identically distributed (iid). EL performs well even when the distribution is asymmetric or censored. EL methods are also useful since they can easily incorporate constraints and prior information. Art Owen pioneered work in this area with his 1988 paper. Empirical Orthogonal Function Analysis(EOF) In statistics, EOF analysis is known as Principal Component Analysis (PCA). As such, EOF analysis is sometimes classified as a multivariate statistical technique. Empirical Orthogonal Teleconnections(EOT) Calculating functions empirically and orthogonally from a given space-time dataset. The method is rooted in multiple linear regression and yields solutions that are orthogonal in one direction, either space or time. remote Empirical Requirements Research Classifier(ERRC) Research must be reproducible in order to make an impact on science and to contribute to the body of knowledge in our field. Yet studies have shown that 70% of research from academic labs cannot be reproduced. In software engineering, and more specifically requirements engineering (RE), reproducible research is rare, with datasets not always available or methods not fully described. This lack of reproducible research hinders progress, with researchers having to replicate an experiment from scratch. A researcher starting out in RE has to sift through conference papers, finding ones that are empirical, then must look through the data available from the empirical paper (if any) to make a preliminary determination if the paper can be reproduced. This paper addresses two parts of that problem, identifying RE papers and identifying empirical papers within the RE papers. Recent RE and empirical conference papers were used to learn features and to build an automatic classifier to identify RE and empirical papers. We introduce the Empirical Requirements Research Classifier (ERRC) method, which uses natural language processing and machine learning to perform supervised classification of conference papers. We compare our method to a baseline keyword-based approach. To evaluate our approach, we examine sets of papers from the IEEE Requirements Engineering conference and the IEEE International Symposium on Software Testing and Analysis. We found that the ERRC method performed better than the baseline method in all but a few cases. Enclosure Diagram The enclosure diagram is also space filling, using containment rather than adjacency to represent the hierarchy. Introduced by Ben Shneiderman in 1991, a treemap recursively subdivides area into rectangles. As with adjacency diagrams, the size of any node in the tree is quickly revealed. Encoder Based Lifelong Learning This paper introduces a new lifelong learning solution where a single model is trained for a sequence of tasks. The main challenge that vision systems face in this context is catastrophic forgetting: as they tend to adapt to the most recently seen task, they lose performance on the tasks that were learned previously. Our method aims at preserving the knowledge of the previous tasks while learning a new one by using autoencoders. For each task, an under-complete autoencoder is learned, capturing the features that are crucial for its achievement. When a new task is presented to the system, we prevent the reconstructions of the features with these autoencoders from changing, which has the effect of preserving the information on which the previous tasks are mainly relying. At the same time, the features are given space to adjust to the most recent environment as only their projection into a low dimension submanifold is controlled. The proposed system is evaluated on image classification tasks and shows a reduction of forgetting over the state-of-the-art Encog Encog is an advanced machine learning framework that supports a variety of advanced algorithms, as well as support classes to normalize and process data. Machine learning algorithms such as Support Vector Machines, Artificial Neural Networks, Genetic Programming, Bayesian Networks, Hidden Markov Models, Genetic Programming and Genetic Algorithms are supported. Most Encog training algoritms are multi-threaded and scale well to multicore hardware. Encog can also make use of a GPU to further speed processing time. A GUI based workbench is also provided to help model and train machine learning algorithms. Encog has been in active development since 2008. Encog: Library of Interchangeable Machine Learning Models for Java and C# End of Potential Line(EOPL) We introduce the problem EndOfPotentialLine and the corresponding complexity class EOPL of all problems that can be reduced to it in polynomial time. This class captures problems that admit a single combinatorial proof of their joint membership in the complexity classes PPAD of fixpoint problems and PLS of local search problems. EOPL is a combinatorially-defined alternative to the class CLS (for Continuous Local Search), which was introduced in with the goal of capturing the complexity of some well-known problems in PPAD $\cap$ PLS that have resisted, in some cases for decades, attempts to put them in polynomial time. Two of these are Contraction, the problem of finding a fixpoint of a contraction map, and P-LCP, the problem of solving a P-matrix Linear Complementarity Problem. We show that EndOfPotentialLine is in CLS via a two-way reduction to EndOfMeteredLine. The latter was defined in to show query and cryptographic lower bounds for CLS. Our two main results are to show that both PL-Contraction (Piecewise-Linear Contraction) and P-LCP are in EOPL. Our reductions imply that the promise versions of PL-Contraction and P-LCP are in the promise class UniqueEOPL, which corresponds to the case of a single potential line. This also shows that simple-stochastic, discounted, mean-payoff, and parity games are in EOPL. Using the insights from our reduction for PL-Contraction, we obtain the first polynomial-time algorithms for finding fixed points of contraction maps in fixed dimension for any $\ell_p$ norm, where previously such algorithms were only known for the $\ell_2$ and $\ell_\infty$ norms. Our reduction from P-LCP to EndOfPotentialLine allows a technique of Aldous to be applied, which in turn gives the fastest-known randomized algorithm for the P-LCP. Endogenous Variable In a statistical model, a parameter or variable is said to be endogenous when there is a correlation between the parameter or variable and the error term. Endogeneity can arise as a result of measurement error, autoregression with autocorrelated errors, simultaneity and omitted variables. Broadly, a loop of causality between the independent and dependent variables of a model leads to endogeneity. For example, in a simple supply and demand model, when predicting the quantity demanded in equilibrium, the price is endogenous because producers change their price in response to demand and consumers change their demand in response to price. In this case, the price variable is said to have total endogeneity once the demand and supply curves are known. In contrast, a change in consumer tastes or preferences would be an exogenous change on the demand curve. Energy-based Exploration of Random Features(EERF) The randomized-feature approach has been successfully employed in large-scale kernel approximation and supervised learning. The distribution from which the random features are drawn impacts the number of features required to efficiently perform a learning task. Recently, it has been shown that employing data-dependent randomization improves the performance in terms of the required number of random features. In this paper, we are concerned with the randomized-feature approach in supervised learning for good generalizability. We propose the Energy-based Exploration of Random Features (EERF) algorithm based on a data-dependent score function that explores the set of possible features and exploits the promising regions. We prove that the proposed score function with high probability recovers the spectrum of the best fit within the model class. Our empirical results on several benchmark datasets further verify that our method requires smaller number of random features to achieve a certain generalization error compared to the state-of-the-art while introducing negligible pre-processing overhead. EERF can be implemented in a few lines of code and requires no additional tuning parameters. EnergyNet We present ENERGYNET , a new framework for analyzing and building artificial neural network architectures. Our approach adaptively learns the structure of the networks in an unsupervised manner. The methodology is based upon the theoretical guarantees of the energy function of restricted Boltzmann machines (RBM) of infinite number of nodes. We present experimental results to show that the final network adapts to the complexity of a given problem. ENet The ability to perform pixel-wise semantic segmentation in real-time is of paramount importance in mobile applications. Recent deep neural networks aimed at this task have the disadvantage of requiring a large number of floating point operations and have long run-times that hinder their usability. In this paper, we propose a novel deep neural network architecture named ENet (efficient neural network), created specifically for tasks requiring low latency operation. ENet is up to 18× faster, requires 75× less FLOPs, has 79× less parameters, and provides similar or better accuracy to existing models. We have tested it on CamVid, Cityscapes and SUN datasets and report on comparisons with existing state-of-the-art methods, and the trade-offs between accuracy and processing time of a network. We present performance measurements of the proposed architecture on embedded systems and suggest possible software improvements that could make ENet even faster. Enhanced Least Absolute Shrinkage Operator(ELASSO) elasso Ensemble Bayesian Optimization(EBO) Bayesian Optimization (BO) has been shown to be a very effective paradigm for tackling hard black-box and non-convex optimization problems encountered in Machine Learning. Despite these successes, the computational complexity of the underlying function approximation has restricted the use of BO to problems that can be handled with less than a few thousand function evaluations. Harder problems like those involving functions operating in very high dimensional spaces may require hundreds of thousands or millions of evaluations or more and become computationally intractable to handle using standard Bayesian Optimization methods. In this paper, we propose Ensemble Bayesian Optimization (EBO) to overcome this problem. Unlike conventional BO methods that operate on a single posterior GP model, EBO works with an ensemble of posterior GP models. Further, we represent each GP model using tile coding random features and an additive function structure. Our approach generates speedups by parallelizing the time consuming hyper-parameter posterior inference and functional evaluations on hundreds of cores and aggregating the models in every iteration of BO. Our extensive experimental evaluation shows that EBO can speed up the posterior inference between 2-3 orders of magnitude (400 times in one experiment) compared to the state-of-the-art by putting data into Mondrian bins without sacrificing the sample quality. We demonstrate the ability of EBO to handle sample-intensive hard optimization problems by applying it to a rover navigation problem with tens of thousands of observations. Ensemble Empirical Mode Decomposition(EEMD) This approach consists of sifting an ensemble of white noise-added signal (data) and treats the mean as the final true result. Finite, not infinitesimal, amplitude white noise is necessary to force the ensemble to exhaust all possible solutions in the sifting process, thus making the different scale signals to collate in the proper intrinsic mode functions (IMF) dictated by the dyadic filter banks. As EEMD is a time-space analysis method, the added white noise is averaged out with sufficient number of trials; the only persistent part that survives the averaging process is the component of the signal (original data), which is then treated as the true and more physical meaningful answer. The effect of the added white noise is to provide a uniform reference frame in the time-frequency space; therefore, the added noise collates the portion of the signal of comparable scale in one IMF. With this ensemble mean, one can separate scales naturally without any a priori subjective criterion selection as in the intermittence test for the original EMD algorithm. This new approach utilizes the full advantage of the statistical characteristics of white noise to perturb the signal in its true solution neighborhood, and to cancel itself out after serving its purpose; therefore, it represents a substantial improvement over the original EMD and is a truly noise-assisted data analysis (NADA) method. Rlibeemd Ensemble Methods In statistics and machine learning, ensemble methods use multiple learning algorithms to obtain better predictive performance than could be obtained from any of the constituent learning algorithms. Unlike a statistical ensemble in statistical mechanics, which is usually infinite, a machine learning ensemble refers only to a concrete finite set of alternative models, but typically allows for much more flexible structure to exist between those alternatives. Ensemble Partial Least Squares Regression(EnPLS) enpls Enterprise Control Language / Data-Centric Programming Language(ECL) ECL is a declarative, data centric programming language designed in 2000 to allow a team of programmers to process big data across a high performance computing cluster without the programmer being involved in many of the lower level, imperative decisions. Enterprise Data Hub(EDH) Organizations everywhere are grappling with how to manage their growing big data sets from ERP and e-commerce systems, log files, sensor data, social media and more. Apache Hadoop provides a cost-effective enterprise data hub (EDH) to store, transform, cleanse, filter, analyze and gain new value from all kinds of data. Enterprise Information Flow(EIF) What is Enterprise Information Flow? The concept is closely connected to its neighboring disciplines: Information Flow, Data Lineage Analysis and Metadata Management. But it’s not the same. This new buzzword is only beginning to be recognized, so let’s get a head start. Information Flow focuses on information processing when it comes to security, throughput optimization and transporters; Data Lineage Analysis studies the way data is transferred between systems; and Metadata Management is all about metadata structure and purpose. Why do we need a new concept then? • Big data is getting really big. From internal company systems, social networks and external data from partners to automatically collected data – a huge amount of information needs to be properly dealt with. The high volume of data is of course connected to the high volume of contributing sources: dozens of online channels, the previously mentioned social networks, portable devices, blogs, news and video content. And every source needs to be correctly described, attributed and integrated into the company’s Enterprise Information Flow. • Systems are getting more and more complicated. EIF needs to be ready not only for big data coming from a wide variety of channels, but also for the many different ways data is transformed and processed inside the system. Old school transformation methods like ETL and SQL scripts are easy and usually well-accounted for, but cracks start to show when it comes to the semantic analysis of non-structured data, Google’s search algorithms, Facebook’s preferential algorithms, automated quality assurance scripts or artificial intelligence methods used for predictive analysis. When it comes to transformations, it’s critical to know how security and other specific attributes change. Another key point is deciding if the information is created or just transformed. • New routes between systems. The number of different ways to transfer data between systems is rapidly growing. Classic ETL and extract transfers are joined by more complicated systems based on SOA, PBM and ESB. It’s also necessary to be ready for new approaches like Data Federation and Logical Data Warehouse, where data saving is not persistent. • Different data types. It’s not about relational data or text anymore. You need to be ready for NoSQL databases, hyperlinks, video, graphics, xml, semi-structured data and other types of information. In complicated environments like these, current solutions fail. New approaches need to be more complex, as the new systems are. It’s necessary to follow data not only on a physical level, but also through more layers of logical abstraction. Let’s sum it up into two main angles of Enterprise Information Flow: 1) New information necessary for decision making appears. Where does it come from? When was it created? Who’s responsible for its quality? 2) Who uses my information and how? Those two sets of questions are vital to Enterprise Information Flow which is a standard part of Enterprise Information Management. Any organization who takes its data seriously is searching for answers anyway, but EIF can provide a more comprehensive overview and merge existing solutions from currently separated fields into one complex policy. A complex solution is precisely what you need, when you’re dealing with complex systems. Entity Resolution(ER) Entity Resolution (ER), the problem of extracting, matching and resolving entity mentions in structured and unstructured data, is a long-standing challenge in database management, information retrieval, machine learning, natural language processing and statistics. Ironically, different subdisciplines refer to it by a variety of names, including record linkage, deduplication, co-reference resolution, reference reconciliation, object consolidation, identity uncertainty and database hardening. Accurate and fast ER has huge practical implications in a wide variety of commercial, scientific and security domains. Despite the long history of work on ER there is still a surprising diversity of approaches – including rule based methods, pair-wise classification, clustering approaches, and richer forms of probabilistic inference – and a lack of guiding theory. Meanwhile, in the age of big data, the need for high quality entity resolution is only growing. We are inundated with more and more data that needs to be integrated, aligned and matched before further utility can be extracted. Entity-Duet Neural Ranking Model(EDRM) This paper presents the Entity-Duet Neural Ranking Model (EDRM), which introduces knowledge graphs to neural search systems. EDRM represents queries and documents by their words and entity annotations. The semantics from knowledge graphs are integrated in the distributed representations of their entities, while the ranking is conducted by interaction-based neural ranking networks. The two components are learned end-to-end, making EDRM a natural combination of entity-oriented search and neural information retrieval. Our experiments on a commercial search log demonstrate the effectiveness of EDRM. Our analyses reveal that knowledge graph semantics significantly improve the generalization ability of neural ranking models. Entropic Spectral Learning We present a novel algorithm for learning the spectral density of large scale networks using stochastic trace estimation and the method of maximum entropy. The complexity of the algorithm is linear in the number of non-zero elements of the matrix, offering a computational advantage over other algorithms. We apply our algorithm to the problem of community detection in large networks. We show state-of-the-art performance on both synthetic and real datasets. Entropy In information theory, entropy is a measure of the uncertainty in a random variable. In this context, the term usually refers to the Shannon entropy, which quantifies the expected value of the information contained in a message. Entropy is typically measured in bits, nats, or bans. Shannon entropy is the average unpredictability in a random variable, which is equivalent to its information content. Shannon entropy provides an absolute limit on the best possible lossless encoding or compression of any communication, assuming that the communication may be represented as a sequence of independent and identically distributed random variables. Entropy Agglomeration(EA) ➘ “Entropy Agglomeration” Episodic Memory Deep Q-Network(EMDQN) Reinforcement learning (RL) algorithms have made huge progress in recent years by leveraging the power of deep neural networks (DNN). Despite the success, deep RL algorithms are known to be sample inefficient, often requiring many rounds of interaction with the environments to obtain satisfactory performance. Recently, episodic memory based RL has attracted attention due to its ability to latch on good actions quickly. In this paper, we present a simple yet effective biologically inspired RL algorithm called Episodic Memory Deep Q-Networks (EMDQN), which leverages episodic memory to supervise an agent during training. Experiments show that our proposed method can lead to better sample efficiency and is more likely to find good policies. It only requires 1/5 of the interactions of DQN to achieve many state-of-the-art performances on Atari games, significantly outperforming regular DQN and other episodic memory based RL algorithms. Epsilon-Greedy Algorithm To get you started thinking algorithmically about the Explore-Exploit dilemma, we’re going to teach you how to code up one of the simplest possible algorithms for trading off exploration and exploitation. This algorithm is called the epsilon-Greedy algorithm. In computer science, a greedy algorithm is an algorithm that always takes whatever action seems best at the present moment, even when that decision might lead to bad long term consequences. The epsilon-Greedy algorithm is almost a greedy algorithm because it generally exploits the best available option, but every once in a while the epsilon-Greedy algorithm explores the other available options. As we’ll see, the term epsilon in the algorithm’s name refers to the odds that the algorithm explores instead of exploiting. Let’s be more specific. The epsilon-Greedy algorithm works by randomly oscillating between Cynthia’s vision of purely randomized experimentation and Bob’s instinct to maximize profits. The epsilon-Greedy algorithm is one of the easiest bandit algorithms to understand because it tries to be fair to the two opposite goals of exploration and exploitation by using a mechanism that even a little kid could understand: it just flips a coin. While there are a few details we’ll have to iron out to make that statement precise, the big idea behind the epsilon-Greedy algorithm really is that simple: if you flip a coin and it comes up heads, you … epsilon-ResNet A family of super deep networks, referred to as residual networks or ResNet, achieved record-beating performance in various visual tasks such as image recognition, object detection, and semantic segmentation. The ability to train very deep networks naturally pushed the researchers to use enormous resources to achieve the best performance. Consequently, in many applications super deep residual networks were employed for just a marginal improvement in performance. In this paper, we propose $\epsilon$-ResNet that allows us to automatically discard redundant layers, which produces responses that are smaller than a threshold $\epsilon$, without any loss in performance. The $\epsilon$-ResNet architecture can be achieved using a few additional rectified linear units in the original ResNet. Our method does not use any additional variables nor numerous trials like other hyper-parameter optimization techniques. The layer selection is achieved using a single training process and the evaluation is performed on CIFAR-10, CIFAR-100, SVHN, and ImageNet datasets. In some instances, we achieve about 80\% reduction in the number of parameters. Epsilon-Subgradient Descent Minimax optimization plays a key role in adversarial training of machine learning algorithms, such as learning generative models, domain adaptation, privacy preservation, and robust learning. In this paper, we demonstrate the failure of alternating gradient descent in minimax optimization problems due to the discontinuity of solutions of the inner maximization. To address this, we propose a new epsilon-subgradient descent algorithm that addresses this problem by simultaneously tracking K candidate solutions. Practically, the algorithm can find solutions that previous saddle-point algorithms cannot find, with only a sublinear increase of complexity in K. We analyze the conditions under which the algorithm converges to the true solution in detail. A significant improvement in stability and convergence speed of the algorithm is observed in simple representative problems, GAN training, and domain-adaptation problems. Equivalent Class Optimization(EC-Opt) It has been widely observed that many activation functions and pooling methods of neural network models have (positive-) rescaling-invariant property, including ReLU, PReLU, max-pooling, and average pooling, which makes fully-connected neural networks (FNNs) and convolutional neural networks (CNNs) invariant to (positive) rescaling operation across layers. This may cause unneglectable problems with their optimization: (1) different NN models could be equivalent, but their gradients can be very different from each other; (2) it can be proven that the loss functions may have many spurious critical points in the redundant weight space. To tackle these problems, in this paper, we first characterize the rescaling-invariant properties of NN models using equivalent classes and prove that the dimension of the equivalent class space is significantly smaller than the dimension of the original weight space. Then we represent the loss function in the compact equivalent class space and develop novel algorithms that conduct optimization of the NN models directly in the equivalent class space. We call these algorithms Equivalent Class Optimization (abbreviated as EC-Opt) algorithms. Moreover, we design efficient tricks to compute the gradients in the equivalent class, which almost have no extra computational complexity as compared to standard back-propagation (BP). We conducted experimental study to demonstrate the effectiveness of our proposed new optimization algorithms. In particular, we show that by using the idea of EC-Opt, we can significantly improve the accuracy of the learned model (for both FNN and CNN), as compared to using conventional stochastic gradient descent algorithms. Erase Rectified Linear Unit(EraseReLU) For most state-of-the-art architectures, Rectified Linear Unit (ReLU) becomes a standard component accompanied by each layer. Although ReLU can ease the network training to an extent, the character of blocking negative values may suppress the propagation of useful information and leads to the difficulty of optimizing very deep Convolutional Neural Networks (CNNs). Moreover, stacking of layers with nonlinear activations is hard to approximate the intrinsic linear transformations between feature representations. In this paper, we investigate the effect of erasing ReLUs of certain layers and apply it to various representative architectures. We name our approach as ‘EraseReLU’. It can ease the optimization and improve the generalization performance for very deep CNN models. In experiments, this method successfully improves the performance of various representative architectures, and we report the improved results on SVHN, CIFAR-10/100, and ImageNet-1k. By using EraseReLU, we achieve state-of-the-art single-model performance on CIFAR-100 with 83.47% accuracy. Codes will be released soon. E-RL^2 ➘ “Krazy World” Error Correction Model(ECM) An error correction model belongs to a category of multiple time series models most commonly used for data where the underlying variables have a long-run stochastic trend, also known as cointegration. ECMs are a theoretically-driven approach useful for estimating both short-term and long-term effects of one time series on another. The term error-correction relates to the fact that last-periods deviation from a long-run equilibrium, the error, influences its short-run dynamics. Thus ECMs directly estimate the speed at which a dependent variable returns to equilibrium after a change in other variables. ecm Error Matrix Error-Robust Multi-View Clustering(EMVC) In the era of big data, data may come from multiple sources, known as multi-view data. Multi-view clustering aims at generating better clusters by exploiting complementary and consistent information from multiple views rather than relying on the individual view. Due to inevitable system errors caused by data-captured sensors or others, the data in each view may be erroneous. Various types of errors behave differently and inconsistently in each view. More precisely, error could exhibit as noise and corruptions in reality. Unfortunately, none of the existing multi-view clustering approaches handle all of these error types. Consequently, their clustering performance is dramatically degraded. In this paper, we propose a novel Markov chain method for Error-Robust Multi-View Clustering (EMVC). By decomposing each view into a shared transition probability matrix and error matrix and imposing structured sparsity-inducing norms on error matrices, we characterize and handle typical types of errors explicitly. To solve the challenging optimization problem, we propose a new efficient algorithm based on Augmented Lagrangian Multipliers and prove its convergence rigorously. Experimental results on various synthetic and real-world datasets show the superiority of the proposed EMVC method over the baseline methods and its robustness against different types of errors. Escort Deep neural networks have achieved remarkable accuracy in many artificial intelligence applications, e.g. computer vision, at the cost of a large number of parameters and high computational complexity. Weight pruning can compress DNN models by removing redundant parameters in the networks, but it brings sparsity in the weight matrix, and therefore makes the computation inefficient on GPUs. Although pruning can remove more than 80% of the weights, it actually hurts inference performance (speed) when running models on GPUs. Two major problems cause this unsatisfactory performance on GPUs. First, lowering convolution onto matrix multiplication reduces data reuse opportunities and wastes memory bandwidth. Second, the sparsity brought by pruning makes the computation irregular, which leads to inefficiency when running on massively parallel GPUs. To overcome these two limitations, we propose Escort, an efficient sparse convolutional neural networks on GPUs. Instead of using the lowering method, we choose to compute the sparse convolutions directly. We then orchestrate the parallelism and locality for the direct sparse convolution kernel, and apply customized optimization techniques to further improve performance. Evaluation on NVIDIA GPUs show that Escort can improve sparse convolution speed by 2.63x and 3.07x, and inference speed by 1.38x and 1.60x, compared to CUBLAS and CUSPARSE respectively. ESN Recurrent Autoencoder(ESN-RAE) It is a widely accepted fact that data representations intervene noticeably in machine learning tools. The more they are well defined the better the performance results are. Feature extraction-based methods such as autoencoders are conceived for finding more accurate data representations from the original ones. They efficiently perform on a specific task in terms of 1) high accuracy, 2) large short term memory and 3) low execution time. Echo State Network (ESN) is a recent specific kind of Recurrent Neural Network which presents very rich dynamics thanks to its reservoir-based hidden layer. It is widely used in dealing with complex non-linear problems and it has outperformed classical approaches in a number of tasks including regression, classification, etc. In this paper, the noticeable dynamism and the large memory provided by ESN and the strength of Autoencoders in feature extraction are gathered within an ESN Recurrent Autoencoder (ESN-RAE). In order to bring up sturdier alternative to conventional reservoir-based networks, not only single layer basic ESN is used as an autoencoder, but also Multi-Layer ESN (ML-ESN-RAE). The new features, once extracted from ESN’s hidden layer, are applied to classification tasks. The classification rates rise considerably compared to those obtained when applying the original data features. An accuracy-based comparison is performed between the proposed recurrent AEs and two variants of an ELM feed-forward AEs (Basic and ML) in both of noise free and noisy environments. The empirical study reveals the main contribution of recurrent connections in improving the classification performance results. ESPnet This paper introduces a new open source platform for end-to-end speech processing named ESPnet. ESPnet mainly focuses on end-to-end automatic speech recognition (ASR), and adopts widely-used dynamic neural network toolkits, Chainer and PyTorch, as a main deep learning engine. ESPnet also follows the Kaldi ASR toolkit style for data processing, feature extraction/format, and recipes to provide a complete setup for speech recognition and other speech processing experiments. This paper explains a major architecture of this software platform, several important functionalities, which differentiate ESPnet from other open source ASR toolkits, and experimental results with major ASR benchmarks. Espresso There are many applications scenarios for which the computational performance and memory footprint of the prediction phase of Deep Neural Networks (DNNs) needs to be optimized. Binary Neural Networks (BDNNs) have been shown to be an effective way of achieving this objective. In this paper, we show how Convolutional Neural Networks (CNNs) can be implemented using binary representations. Espresso is a compact, yet powerful library written in C/CUDA that features all the functionalities required for the forward propagation of CNNs, in a binary file less than 400KB, without any external dependencies. Although it is mainly designed to take advantage of massive GPU parallelism, Espresso also provides an equivalent CPU implementation for CNNs. Espresso provides special convolutional and dense layers for BCNNs, leveraging bit-packing and bit-wise computations for efficient execution. These techniques provide a speed-up of matrix-multiplication routines, and at the same time, reduce memory usage when storing parameters and activations. We experimentally show that Espresso is significantly faster than existing implementations of optimized binary neural networks ($\approx$ 2 orders of magnitude). Espresso is released under the Apache 2.0 license and is available at http://…/espresso. Esri Esri´s GIS (geographic information systems) mapping software helps you understand and visualize data to make decisions based on the best information and analysis. Essence Vector Model(EV) In the context of natural language processing, representation learning has emerged as a newly active research subject because of its excellent performance in many applications. Learning representations of words is a pioneering study in this school of research. However, paragraph (or sentence and document) embedding learning is more suitable/reasonable for some tasks, such as sentiment classification and document summarization. Nevertheless, as far as we are aware, there is relatively less work focusing on the development of unsupervised paragraph embedding methods. Classic paragraph embedding methods infer the representation of a given paragraph by considering all of the words occurring in the paragraph. Consequently, those stop or function words that occur frequently may mislead the embedding learning process to produce a misty paragraph representation. Motivated by these observations, our major contributions in this paper are twofold. First, we propose a novel unsupervised paragraph embedding method, named the essence vector (EV) model, which aims at not only distilling the most representative information from a paragraph but also excluding the general background information to produce a more informative low-dimensional vector representation for the paragraph. Second, in view of the increasing importance of spoken content processing, an extension of the EV model, named the denoising essence vector (D-EV) model, is proposed. The D-EV model not only inherits the advantages of the EV model but also can infer a more robust representation for a given spoken paragraph against imperfect speech recognition. Essential Histogram The histogram is widely used as a simple, exploratory display of data, but it is usually not clear how to choose the number and size of bins for this purpose. We construct a confidence set of distribution functions that optimally address the two main tasks of the histogram: estimating probabilities and detecting features such as increases and (anti)modes in the distribution. We define the essential histogram as the histogram in the confidence set with the fewest bins. Thus the essential histogram is the simplest visualization of the data that optimally achieves the main tasks of the histogram. We provide a fast algorithm for computing a slightly relaxed version of the essential histogram, which still possesses most of its beneficial theoretical properties, and we illustrate our methodology with examples. An R-package is available online. Estimability http://…/lenth.pdf http://…/ch06.pdf estimability Euclidean Distance In mathematics, the Euclidean distance or Euclidean metric is the “ordinary” distance between two points that one would measure with a ruler, and is given by the Pythagorean formula. By using this formula as distance, Euclidean space (or even any inner product space) becomes a metric space. The associated norm is called the Euclidean norm. Event Driven Architeture(EDA) Event-driven architecture (EDA) is a software architecture pattern promoting the production, detection, consumption of, and reaction to events. An event can be defined as “a significant change in state”. For example, when a consumer purchases a car, the car’s state changes from “for sale” to “sold”. A car dealer’s system architecture may treat this state change as an event whose occurrence can be made known to other applications within the architecture. From a formal perspective, what is produced, published, propagated, detected or consumed is a (typically asynchronous) message called the event notification, and not the event itself, which is the state change that triggered the message emission. Event History Analysis Event history analysis deals with data obtained by observing individuals over time, focusing on events occurring for the individuals under observation. Important applications are to life events of humans in demography, life insurance mathematics, epidemiology, and sociology. The basic data are the times of occurrence of the events and the types of events that occur. The standard approach to the analysis of such data is to use multistate models; a basic example is finite-state Markov processes in continuous time. Censoring and truncation are defining features of the area. This review comments specifically on three areas that are current subjects of active development, all motivated by demands from applications: sampling patterns, the possibility of causal interpretation of the analyses, and the levels and interpretation of variability. eha Event Schema Induction(ESI) Event Stream Processing(ESP) Event stream processing, or ESP, is a set of technologies designed to assist the construction of event-driven information systems. ESP technologies include event visualization, event databases, event-driven middleware, and event processing languages, or complex event processing (CEP). In practice, the terms ESP and CEP are often used interchangeably. ESP deals with the task of processing streams of event data with the goal of identifying the meaningful pattern within those streams, employing techniques such as detection of relationships between multiple events, event correlation, event hierarchies, and other aspects such as causality, membership and timing. ESP enables many different applications such as algorithmic trading in financial services, RFID event processing applications, fraud detection, process monitoring, and location-based services in telecommunications. Event-Centric Temporal Knowledge Graph(EventKG) One of the key requirements to facilitate semantic analytics of information regarding contemporary and historical events on the Web, in the news and in social media is the availability of reference knowledge repositories containing comprehensive representations of events and temporal relations. Existing knowledge graphs, with popular examples including DBpedia, YAGO and Wikidata, focus mostly on entity-centric information and are insufficient in terms of their coverage and completeness with respect to events and temporal relations. EventKG presented in this paper is a multilingual event-centric temporal knowledge graph that addresses this gap. EventKG incorporates over 690 thousand contemporary and historical events and over 2.3 million temporal relations extracted from several large-scale knowledge graphs and semi-structured sources and makes them available through a canonical representation. EventKG+TL The provision of multilingual event-centric temporal knowledge graphs such as EventKG enables structured access to representations of a large number of historical and contemporary events in a variety of language contexts. Timelines provide an intuitive way to facilitate an overview of events related to a \textit{query entity} – i.e. an entity or an event of user interest – over a certain period of time. In this paper, we present \eventTL{} – a novel system that generates cross-lingual event timelines using EventKG and facilitates an overview of the language-specific event relevance and popularity along with the cross-lingual differences. Evidence based Data Analysis What I think the statistical community needs to invest time and energy into is what I call “evidence-based data analysis”. What do I mean by this? Most data analyses are not the simple classroom exercises that we’ve all done involving linear regression or two-sample t-tests. Most of the time, you have to obtain the data, clean that data, remove outliers, impute missing values, transform variables and on and on, even before you fit any sort of model. Then there’s model selection, model fitting, diagnostics, sensitivity analysis, and more. So a data analysis is really pipeline of operations where the output of one stage becomes the input of another. The basic idea behind evidence-based data analysis is that for each stage of that pipeline, we should be using the best method, justified by appropriate statistical research that provides evidence favoring one method over another. If we cannot reasonable agree on a best method for a given stage in the pipeline, then we have a gap that needs to be filled. So we fill it! Evidence Lower Bound(ELBO) (Section: 2.2 The Evidence Lower Bound) Filtering Variational Objectives ➘ “Filtering Variational Objectives” Evidence-Driven State-Merging(EDSM) Human in the Loop: Interactive Passive Automata Learning via Evidence-Driven State-Merging Algorithms Evidential C-Medoids(ECMdd) In this work, a new prototype-based clustering method named Evidential C-Medoids (ECMdd), which belongs to the family of medoid-based clustering for proximity data, is proposed as an extension of Fuzzy C-Medoids (FCMdd) on the theoretical framework of belief functions. In the application of FCMdd and original ECMdd, a single medoid (prototype), which is supposed to belong to the object set, is utilized to represent one class. For the sake of clarity, this kind of ECMdd using a single medoid is denoted by sECMdd. In real clustering applications, using only one pattern to capture or interpret a class may not adequately model different types of group structure and hence limits the clustering performance. In order to address this problem, a variation of ECMdd using multiple weighted medoids, denoted by wECMdd, is presented. Unlike sECMdd, in wECMdd objects in each cluster carry various weights describing their degree of representativeness for that class. This mechanism enables each class to be represented by more than one object. Experimental results in synthetic and real data sets clearly demonstrate the superiority of sECMdd and wECMdd. Moreover, the clustering results by wECMdd can provide richer information for the inner structure of the detected classes with the help of prototype weights. Evolution Strategy(ES) In computer science, an evolution strategy (ES) is an optimization technique based on ideas of adaptation and evolution. It belongs to the general class of evolutionary computation or artificial evolution methodologies. Evolutionary Algorithm(EA) In artificial intelligence, an evolutionary algorithm (EA) is a subset of evolutionary computation, a generic population-based metaheuristic optimization algorithm. An EA uses mechanisms inspired by biological evolution, such as reproduction, mutation, recombination, and selection. Candidate solutions to the optimization problem play the role of individuals in a population, and the fitness function determines the quality of the solutions. Evolution of the population then takes place after the repeated application of the above operators. Artificial evolution (AE) describes a process involving individual evolutionary algorithms; EAs are individual components that participate in an AE. Evolutionary Cost-Sensitive Deep Belief Network Imbalanced data with a skewed class distribution are common in many real-world applications. Deep Belief Network (DBN) is a machine learning technique that is effective in classification tasks. However, conventional DBN does not work well for imbalanced data classification because it assumes equal costs for each class. To deal with this problem, cost-sensitive approaches assign different misclassification costs for different classes without disrupting the true data sample distributions. However, due to lack of prior knowledge, the misclassification costs are usually unknown and hard to choose in practice. Moreover, it has not been well studied as to how cost-sensitive learning could improve DBN performance on imbalanced data problems. This paper proposes an evolutionary cost-sensitive deep belief network (ECS-DBN) for imbalanced classification. ECS-DBN uses adaptive differential evolution to optimize the misclassification costs based on training data, that presents an effective approach to incorporating the evaluation measure (i.e. G-mean) into the objective function. We first optimize the misclassification costs, then apply them to deep belief network. Adaptive differential evolution optimization is implemented as the optimization algorithm that automatically updates its corresponding parameters without the need of prior domain knowledge. The experiments have shown that the proposed approach consistently outperforms the state-of-the-art on both benchmark datasets and real-world dataset for fault diagnosis in tool condition monitoring. Evolutionary DEep Networks(EDEN) Deep neural networks continue to show improved performance with increasing depth, an encouraging trend that implies an explosion in the possible permutations of network architectures and hyperparameters for which there is little intuitive guidance. To address this increasing complexity, we propose Evolutionary DEep Networks (EDEN), a computationally efficient neuro-evolutionary algorithm which interfaces to any deep neural network platform, such as TensorFlow. We show that EDEN evolves simple yet successful architectures built from embedding, 1D and 2D convolutional, max pooling and fully connected layers along with their hyperparameters. Evaluation of EDEN across seven image and sentiment classification datasets shows that it reliably finds good networks — and in three cases achieves state-of-the-art results — even on a single GPU, in just 6-24 hours. Our study provides a first attempt at applying neuro-evolution to the creation of 1D convolutional networks for sentiment analysis including the optimisation of the embedding layer. Evolutionary Generative Adversarial Network(E-GAN) Generative adversarial networks (GAN) have been effective for learning generative models for real-world data. However, existing GANs (GAN and its variants) tend to suffer from training problems such as instability and mode collapse. In this paper, we propose a novel GAN framework called evolutionary generative adversarial networks (E-GAN) for stable GAN training and improved generative performance. Unlike existing GANs, which employ a pre-defined adversarial objective function alternately training a generator and a discriminator, we utilize different adversarial training objectives as mutation operations and evolve a population of generators to adapt to the environment (i.e., the discriminator). We also utilize an evaluation mechanism to measure the quality and diversity of generated samples, such that only well-performing generator(s) are preserved and used for further training. In this way, E-GAN overcomes the limitations of an individual adversarial training objective and always preserves the best offspring, contributing to progress in and the success of GANs. Experiments on several datasets demonstrate that E-GAN achieves convincing generative performance and reduces the training problems inherent in existing GANs. Evolutionary Reinforcement Learning(ERL) Deep Reinforcement Learning (DRL) algorithms have been successfully applied to a range of challenging control tasks. However, these methods typically suffer from three core difficulties: temporal credit assignment with sparse rewards, lack of effective exploration, and brittle convergence properties that are extremely sensitive to hyperparameters. Collectively, these challenges severely limit the applicability of these approaches to real world problems. Evolutionary Algorithms (EAs), a class of black box optimization techniques inspired by natural evolution, are well suited to address each of these three challenges. However, EAs typically suffer with high sample complexity and struggle to solve problems that require optimization of a large number of parameters. In this paper, we introduce Evolutionary Reinforcement Learning (ERL), a hybrid algorithm that leverages the population of an EA to provide diversified data to train an RL agent, and reinserts the RL agent into the EA population periodically to inject gradient information into the EA. ERL inherits EA’s ability of temporal credit assignment with a fitness metric, effective exploration with a diverse set of policies, and stability of a population-based approach and complements it with off-policy DRL’s ability to leverage gradients for higher sample efficiency and faster learning. Experiments in a range of challenging continuous control benchmark tasks demonstrate that ERL significantly outperforms prior DRL and EA methods, achieving state-of-the-art performances. Evolving Fuzzy System(EFS) Evolving fuzzy systems (EFS) can be defined as self-developing, self-learning fuzzy rule-based or neuro-fuzzy systems that have both their parameters but also (more importantly) their structure self-adapting on-line. They are usually associated with streaming data and on-line (often real-time) modes of operation. In a narrower sense they can be seen as adaptive fuzzy systems. The difference is that evolving fuzzy systems assume on-line adaptation of system structure in addition to the parameter adaptation which is usually associated with the term adaptive. They also allow for adaptation of the learning mechanism. Therefore, evolving assumes a higher level of adaptation. In this definition the English word evolving is used with its core meaning as described in the Oxford dictionary (Hornby, 1974; p.294), namely unfolding; developing; being developed, naturally and gradually. Often evolving is used in relation to so called evolutionary and genetic algorithms. The meaning of the term evolutionary is defined in the Oxford dictionary as development of more complicated forms of life (plants, animals) from earlier and simpler forms. EFS consider a gradual development of the underlying (fuzzy or neuro-fuzzy) system structure and do not deal with such phenomena specific for the evolutionary and genetic algorithms as chromosomes crossover, mutation, selection and reproduction, parents and off-springs. ➘ “Evolving Intelligent System” Evolving Intelligent System(EIS) The term Evolving was first used to describe an intelligent system in 1996 by B. Carse, T. Fogarty and A Munro for a fuzzy rule-based controller where its parameters and structure were learnt simultaneously using a Genetic Algorithm. Years later, alternative methods to learn an evolving intelligent system (EIS) via Incremental learning were suggested as a neuro-fuzzy algorithm by N. Kasabov in 1998 and a rule-based model by P. Angelov in 1999. EIS are usually associated with, streaming data and on-line (often real-time) modes of operation. They can be seen as adaptive intelligent systems. EIS assumes on-line adaptation of system structure in addition to the parameter adaptation which is usually associated with the term ‘incremental’ from Incremental learning. They have been studied as a methodological solution to learn from streaming data exhibiting non-stationary behaviours by M. Sayed-Mouchaweh and E. Lughofer. An important sub-area of EIS is represented by Evolving Fuzzy Systems (EFS) (a comprehensive survey written by E. Lughofer including real-world applications can be found in ), which rely on fuzzy systems architecture and incrementally update, evolve and prune fuzzy sets and fuzzy rules on demand and on-the-fly. One of the major strengths of EFS, compared to other forms of evolving system models, is that they are able to support some sort of interpretability and understandability for experts and users. This opens possibilities for enriched human-machine interaction’s scenarios, where the users may ‘communicate’ with an on-line evolving system in form of knowledge exchange (active learning (machine learning) and teaching). This concept is currently motivated and discussed in the evolving systems community under the term Human-Inspired Evolving Machines and respected as ‘one future’ generation of ‘EIS’. ➘ “PANFIS++” Exact Soft Confidence-Weighted Learning In this paper, we propose a new Soft Confidence-Weighted (SCW) online learning scheme, which enables the conventional confidence-weighted learning method to handle non-separable cases. Unlike the previous confidence-weighted learning algorithms, the proposed soft confidence-weighted learning method enjoys all the four salient properties: (i) large margin training, (ii) confidence weighting, (iii) capability to handle non-separable data, and (iv) adaptive margin. Our experimental results show that the proposed SCW algorithms significantly outperform the original CW algorithm. When comparing with a variety of state-of-theart algorithms (including AROW, NAROW and NHERD), we found that SCW generally achieves better or at least comparable predictive accuracy, but enjoys significant advantage of computational efficiency (i.e., smaller number of updates and lower time cost). Excess Relative Risk Model rERR Excess Risk In statistics, excess risk is a measure of the relationship between a specified risk factor and a specified outcome (such as contracting a disease). It is the difference between two proportions. In epidemiology it is typically defined to be the difference between the proportion of subjects in a population with a particular disease who were exposed to a specified risk factor and the proportion of subjects with that same disease who were not exposed. ExGUtils The study of reaction times and their underlying cognitive processes is an important field in Psychology. Reaction times are usually modeled through the ex-Gaussian distribution, because it provides a good fit to multiple empirical data. The complexity of this distribution makes the use of computational tools an essential element in the field. Therefore, there is a strong need for efficient and versatile computational tools for the research in this area. In this manuscript we discuss some mathematical details of the ex-Gaussian distribution and apply the ExGUtils package, a set of functions and numerical tools, programmed for python, developed for numerical analysis of data involving the ex-Gaussian probability density. In order to validate the package, we present an extensive analysis of fits obtained with it, discuss advantages and differences between the least squares and maximum likelihood methods and quantitatively evaluate the goodness of the obtained fits (which is usually an overlooked point in most literature in the area). The analysis done allows one to identify outliers in the empirical datasets and criteriously determine if there is a need for data trimming and at which points it should be done. Exogenous Variable Exogenous variables in causal modeling are the variables with no causal links (arrows) leading to them from other variables in the model. In other words, exogenous variables have no explicit causes within the model. The concept of exogenous variable is fundamental in path analysis and structural equation modeling. The complementary concept is endogenous variable. Expectation Maximization(EM) In statistics, an expectation-maximization (EM) algorithm is an iterative method for finding maximum likelihood or maximum a posteriori (MAP) estimates of parameters in statistical models, where the model depends on unobserved latent variables. The EM iteration alternates between performing an expectation (E) step, which creates a function for the expectation of the log-likelihood evaluated using the current estimate for the parameters, and a maximization (M) step, which computes parameters maximizing the expected log-likelihood found on the E step. These parameter-estimates are then used to determine the distribution of the latent variables in the next E step. Expectation Propagation(EP) Expectation Propagation (EP) is a technique in Bayesian machine learning. EP finds approximations to a probability distribution. It uses an iterative approach that leverages the factorization structure of the target distribution. It differs from other Bayesian approximation approaches such as Variational Bayesian methods. Expectation-Biasing State-of-the-art forecasting methods using Recurrent Neural Net- works (RNN) based on Long-Short Term Memory (LSTM) cells have shown exceptional performance targeting short-horizon forecasts, e.g given a set of predictor features, forecast a target value for the next few time steps in the future. However, in many applications, the performance of these methods decays as the forecasting horizon extends beyond these few time steps. This paper aims to explore the challenges of long-horizon forecasting using LSTM networks. Here, we illustrate the long-horizon forecasting problem in datasets from neuroscience and energy supply management. We then propose expectation-biasing, an approach motivated by the literature of Dynamic Belief Networks, as a solution to improve long-horizon forecasting using LSTMs. We propose two LSTM architectures along with two methods for expectation biasing that significantly outperforms standard practice. Expected Improvement(EI) Improving the Expected Improvement Algorithm Expected Policy Gradient(EPG) We propose expected policy gradients (EPG), which unify stochastic policy gradients (SPG) and deterministic policy gradients (DPG) for reinforcement learning. Inspired by expected sarsa, EPG integrates (or sums) across actions when estimating the gradient, instead of relying only on the action in the sampled trajectory. For continuous action spaces, we first derive a practical result for Gaussian policies and quadric critics and then extend it to an analytical method for the universal case, covering a broad class of actors and critics, including Gaussian, exponential families, and reparameterised policies with bounded support. For Gaussian policies, we show that it is optimal to explore using covariance proportional to the matrix exponential of the scaled Hessian of the critic with respect to the actions. EPG also provides a general framework for reasoning about policy gradient methods, which we use to establish a new general policy gradient theorem, of which the stochastic and deterministic policy gradient theorems are special cases. Furthermore, we prove that EPG reduces the variance of the gradient estimates without requiring deterministic policies and with little computational overhead. Finally, we show that EPG outperforms existing approaches on six challenging domains involving the simulated control of physical systems. EXPected Similarity Estimation(EXPoSE) We present a novel algorithm for anomaly detection on very large datasets and data streams. The method, named EXPected Similarity Estimation (EXPoSE), is kernel-based and able to efficiently compute the similarity between new data points and the distribution of regular data. The estimator is formulated as an inner product with a reproducing kernel Hilbert space embedding and makes no assumption about the type or shape of the underlying data distribution. We show that offline (batch) learning with EXPoSE can be done in linear time and online (incremental) learning takes constant time per instance and model update. Furthermore, EXPoSE can make predictions in constant time, while it requires only constant memory. In addition we propose different methodologies for concept drift adaptation on evolving data streams. On several real datasets we demonstrate that our approach can compete with state of the art algorithms for anomaly detection while being significant faster than techniques with the same discriminant power. Expected Utility Hypothesis(EUH) In economics, game theory, and decision theory the expected utility hypothesis is a hypothesis concerning people’s preferences with regard to choices that have uncertain outcomes (gambles). This hypothesis states that if specific axioms are satisfied, the subjective value associated with an individual’s gamble is the statistical expectation of that individual’s valuations of the outcomes of that gamble. This hypothesis has proved useful to explain some popular choices that seem to contradict the expected value criterion (which takes into account only the sizes of the payouts and the probabilities of occurrence), such as occur in the contexts of gambling and insurance. Daniel Bernoulli initiated this hypothesis in 1738. Until the mid-twentieth century, the standard term for the expected utility was the moral expectation, contrasted with ‘mathematical expectation’ for the expected value. The von Neumann-Morgenstern utility theorem provides necessary and sufficient conditions under which the expected utility hypothesis holds. From relatively early on, it was accepted that some of these conditions would be violated by real decision-makers in practice but that the conditions could be interpreted nonetheless as ‘axioms’ of rational choice. Work by Anand (1993) argues against this normative interpretation and shows that ‘rationality’ does not require transitivity, independence or completeness. This view is now referred to as the ‘modern view’ and Anand argues that despite the normative and evidential difficulties the general theory of decision-making based on expected utility is an insightful first order approximation that highlights some important fundamental principles of choice, even if it imposes conceptual and technical limits on analysis which need to be relaxed in real world settings where knowledge is less certain or preferences are more sophisticated. Expected Value of Partial Perfect Information(EVPPI) http://…/WP130003.pdf http://…/seqposterSMDMfina.pdf BCEA Expected Value of Perfect Information(EVPI) In decision theory, the expected value of perfect information (EVPI) is the price that one would be willing to pay in order to gain access to perfect information. http://…/seqposterSMDMfina.pdf Experimental Design Problem Experimental design is a classical problem in statistics and has also found new applications in machine learning. In the experimental design problem, the aim is to estimate an unknown vector x in m-dimensions from linear measurements where a Gaussian noise is introduced in each measurement. The goal is to pick k out of the given n experiments so as to make the most accurate estimate of the unknown parameter x. Given a set S of chosen experiments, the most likelihood estimate x’ can be obtained by a least squares computation. ➚ “Design of Experiments” Expert Iteration Solving sequential decision making problems, such as text parsing, robotic control, and game playing, requires a combination of planning policies and generalisation of those plans. In this paper, we present Expert Iteration, a novel algorithm which decomposes the problem into separate planning and generalisation tasks. Planning new policies is performed by tree search, while a deep neural network generalises those plans. In contrast, standard Deep Reinforcement Learning algorithms rely on a neural network not only to generalise plans, but to discover them too. We show that our method substantially outperforms Policy Gradients in the board game Hex, winning 84.4% of games against it when trained for equal time. Explainability ➚ “Collaborative Black-box and RUle Set Hybrid” Explainable Artificial Intelligence(XAI) Dramatic success in machine learning has led to a torrent of Artificial Intelligence (AI) applications. Continued advances promise to produce autonomous systems that will perceive, learn, decide, and act on their own. However, the effectiveness of these systems is limited by the machine’s current inability to explain their decisions and actions to human users. The Department of Defense is facing challenges that demand more intelligent, autonomous, and symbiotic systems. Explainable AI—especially explainable machine learning—will be essential if future warfighters are to understand, appropriately trust, and effectively manage an emerging generation of artificially intelligent machine partners. The Explainable AI (XAI) program aims to create a suite of machine learning techniques that: • Produce more explainable models, while maintaining a high level of learning performance (prediction accuracy); and • Enable human users to understand, appropriately trust, and effectively manage the emerging generation of artificially intelligent partners. New machine-learning systems will have the ability to explain their rationale, characterize their strengths and weaknesses, and convey an understanding of how they will behave in the future. The strategy for achieving that goal is to develop new or modified machine-learning techniques that will produce more explainable models. These models will be combined with state-of-the-art human-computer interface techniques capable of translating models into understandable and useful explanation dialogues for the end user. Our strategy is to pursue a variety of techniques in order to generate a portfolio of methods that will provide future developers with a range of design options covering the performance-versus-explainability trade space. Explaining Explanations: An Approach to Evaluating Interpretability of Machine Learning Explanatory Artificial Intelligence(XAI) ➚ “Explainable Artificial Intelligence” Explicit Semantic Analysis(ESA) In natural language processing and information retrieval, explicit semantic analysis (ESA) is a vectorial representation of text (individual words or entire documents) that uses a document corpus as a knowledge base. Specifically, in ESA, a word is represented as a column vector in the tf-idf matrix of the text corpus and a document (string of words) is represented as the centroid of the vectors representing its words. Typically, the text corpus is Wikipedia, though other corpora including the Open Directory Project have been used. ESA was designed by Evgeniy Gabrilovich and Shaul Markovitch as a means of improving text categorization and has been used by this pair of researchers to compute what they refer to as ‘semantic relatedness’ by means of cosine similarity between the aforementioned vectors, collectively interpreted as a space of ‘concepts explicitly defined and described by humans’, where Wikipedia articles (or ODP entries, or otherwise titles of documents in the knowledge base corpus) are equated with concepts. The name ‘explicit semantic analysis’ contrasts with latent semantic analysis (LSA), because the use of a knowledge base makes it possible to assign human-readable labels to the concepts that make up the vector space. ESA, as originally posited by Gabrilovich and Markovitch, operates under the assumption that the knowledge base contains topically orthogonal concepts. However, it was later shown by Anderka and Stein that ESA also improves the performance of information retrieval systems when it is based not on Wikipedia, but on the Reuters corpus of newswire articles, which does not satisfy the orthogonality property; in their experiments, Anderka and Stein used newswire stories as ‘concepts’. To explain this observation, links have been shown between ESA and the generalized vector space model. Gabrilovich and Markovitch replied to Anderka and Stein by pointing out that their experimental result was achieved using ‘a single application of ESA (text similarity)’ and ‘just a single, extremely small and homogenous test collection of 50 news documents’. Cross-language explicit semantic analysis (CL-ESA) is a multilingual generalization of ESA. CL-ESA exploits a document-aligned multilingual reference collection (e.g., again, Wikipedia) to represent a document as a language-independent concept vector. The relatedness of two documents in different languages is assessed by the cosine similarity between the corresponding vector representations. http://…-explicit-semantic-analysis-esa-explained Exploration Potential We introduce exploration potential, a quantity for that measures how much a reinforcement learning agent has explored its environment class. In contrast to information gain, exploration potential takes the problem’s reward structure into account. This leads to an exploration criterion that is both necessary and sufficient for asymptotic optimality (learning to act optimally across the entire environment class). Our experiments in multi-armed bandits use exploration potential to illustrate how different algorithms make the tradeoff between exploration and exploitation. Explorative Landscape Analysis(ELA) Exploratory Landscape Analysis subsumes a number of techniques employed to obtain knowledge about the properties of an unknown optimization problem, especially insofar as these properties are important for the performance of optimization algorithms. Wher flacco Exploratory Data Analysis(EDA) In statistics, exploratory data analysis (EDA) is an approach to analyzing data sets to summarize their main characteristics, often with visual methods. A statistical model can be used or not, but primarily EDA is for seeing what the data can tell us beyond the formal modeling or hypothesis testing task. Exploratory data analysis was promoted by John Tukey to encourage statisticians to explore the data, and possibly formulate hypotheses that could lead to new data collection and experiments. EDA is different from initial data analysis (IDA), which focuses more narrowly on checking assumptions required for model fitting and hypothesis testing, and handling missing values and making transformations of variables as needed. EDA encompasses IDA. Exploratory Factor Analysis(EFA) In multivariate statistics, exploratory factor analysis (EFA) is a statistical method used to uncover the underlying structure of a relatively large set of variables. EFA is a technique within factor analysis whose overarching goal is to identify the underlying relationships between measured variables. It is commonly used by researchers when developing a scale (a scale is a collection of questions used to measure a particular research topic) and serves to identify a set of latent constructs underlying a battery of measured variables. It should be used when the researcher has no a priori hypothesis about factors or patterns of measured variables. Measured variables are any one of several attributes of people that may be observed and measured. An example of a measured variable would be the physical height of a human being. Researchers must carefully consider the number of measured variables to include in the analysis. EFA procedures are more accurate when each factor is represented by multiple measured variables in the analysis. EFA is based on the common factor model. Within the common factor model, a function of common factors, unique factors, and errors of measurements expresses measured variables. Common factors influence two or more measured variables, while each unique factor influences only one measured variable and does not explain correlations among measured variables. EFA assumes that any indicator/measured variable may be associated with any factor. When developing a scale, researchers should use EFA first before moving on to confirmatory factor analysis (CFA). EFA requires the researcher to make a number of important decisions about how to conduct the analysis because there is no one set method. http://…/factornew.htm Exponential Moving Average(EMA) An exponential moving average (EMA), also known as an exponentially weighted moving average (EWMA), is a type of infinite impulse response filter that applies weighting factors which decrease exponentially. The weighting for each older datum decreases exponentially, never reaching zero. The graph at right shows an example of the weight decrease. Exponential Random Graph Models(ERGM) Exponential random graph models (ERGMs) are a family of statistical models for analyzing data about social and other networks. Many metrics exist to describe the structural features of an observed network such as the density, centrality, or assortativity. However, these metrics describe the observed network which is only one instance of a large number of possible alternative networks. This set of alternative networks may have similar or dissimilar structural features. To support statistical inference on the processes influencing the formation of network structure, a statistical model should consider the set of all possible alternative networks weighted on their similarity to an observed network. However because network data is inherently relational, it violates the assumptions of independence and identical distribution of standard statistical models like linear regression. Alternative statistical models should reflect the uncertainty associated with a given observation, permit inference about the relative frequency about network substructures of theoretical interest, disambiguating the influence of confounding processes, efficiently representing complex structures, and linking local-level processes to global-level properties. Degree Preserving Randomization, for example, is a specific way in which an observed network could be considered in terms of multiple alternative networks. Exponential Smoothing Exponential smoothing is a technique that can be applied to time series data, either to produce smoothed data for presentation, or to make forecasts. The time series data themselves are a sequence of observations. The observed phenomenon may be an essentially random process, or it may be an orderly, but noisy, process. Whereas in the simple moving average the past observations are weighted equally, exponential smoothing assigns exponentially decreasing weights over time. Exponential smoothing is commonly applied to financial market and economic data, but it can be used with any discrete set of repeated measurements. The simplest form of exponential smoothing should be used only for data without any systematic trend or seasonal components. Exponential-Generalized Truncated Logarithmic(EGTL) In this paper, we introduce a new two-parameter lifetime distribution, called the exponential-generalized truncated logarithmic (EGTL) distribution, by compounding the exponential and generalized truncated logarithmic distributions. Our procedure generalizes the exponential-logarithmic (EL) distribution modelling the reliability of systems by the use of first-order concepts, where the minimum lifetime is considered (Tahmasbi 2008). In our approach, we assume that a system fails if a given number k of the components fails and then, we consider the kth-smallest value of lifetime instead of the minimum lifetime. The reliability and failure rate functions as well as their properties are presented for some special cases. The estimation of the parameters is attained by the maximum likelihood, the expectation maximization algorithm, the method of moments and the Bayesian approach, with a simulation study performed to illustrate the different methods of estimation. The application study is illustrated based on two real data sets used in many applications of reliability. Exposure Machine learning models based on neural networks and deep learning are being rapidly adopted for many purposes. What those models learn, and what they may share, is a significant concern when the training data may contain secrets and the models are public — e.g., when a model helps users compose text messages using models trained on all users’ messages. This paper presents exposure: a simple-to-compute metric that can be applied to any deep learning model for measuring the memorization of secrets. Using this metric, we show how to extract those secrets efficiently using black-box API access. Further, we show that unintended memorization occurs early, is not due to over-fitting, and is a persistent issue across different types of models, hyperparameters, and training strategies. We experiment with both real-world models (e.g., a state-of-the-art translation model) and datasets (e.g., the Enron email dataset, which contains users’ credit card numbers) to demonstrate both the utility of measuring exposure and the ability to extract secrets. Finally, we consider many defenses, finding some ineffective (like regularization), and others to lack guarantees. However, by instantiating our own differentially-private recurrent model, we validate that by appropriately investing in the use of state-of-the-art techniques, the problem can be resolved, with high utility. Extended Autoregressive Model(EAR) Generative models (GMs) such as Generative Adversary Network (GAN) and Variational Auto-Encoder (VAE) have thrived these years and achieved high quality results in generating new samples. Especially in Computer Vision, GMs have been used in image inpainting, denoising and completion, which can be treated as the inference from observed pixels to corrupted pixels. However, images are hierarchically structured which are quite different from many real-world inference scenarios with non-hierarchical features. These inference scenarios contain heterogeneous stochastic variables and irregular mutual dependences. Traditionally they are modeled by Bayesian Network (BN). However, the learning and inference of BN model are NP-hard thus the number of stochastic variables in BN is highly constrained. In this paper, we adapt typical GMs to enable heterogeneous learning and inference in polynomial time.We also propose an extended autoregressive (EAR) model and an EAR with adversary loss (EARA) model and give theoretical results on their effectiveness. Experiments on several BN datasets show that our proposed EAR model achieves the best performance in most cases compared to other GMs. Except for black box analysis, we’ve also done a serial of experiments on Markov border inference of GMs for white box analysis and give theoretical results. Extended Autoregressive Model with Adversary Loss(EARA) Generative models (GMs) such as Generative Adversary Network (GAN) and Variational Auto-Encoder (VAE) have thrived these years and achieved high quality results in generating new samples. Especially in Computer Vision, GMs have been used in image inpainting, denoising and completion, which can be treated as the inference from observed pixels to corrupted pixels. However, images are hierarchically structured which are quite different from many real-world inference scenarios with non-hierarchical features. These inference scenarios contain heterogeneous stochastic variables and irregular mutual dependences. Traditionally they are modeled by Bayesian Network (BN). However, the learning and inference of BN model are NP-hard thus the number of stochastic variables in BN is highly constrained. In this paper, we adapt typical GMs to enable heterogeneous learning and inference in polynomial time.We also propose an extended autoregressive (EAR) model and an EAR with adversary loss (EARA) model and give theoretical results on their effectiveness. Experiments on several BN datasets show that our proposed EAR model achieves the best performance in most cases compared to other GMs. Except for black box analysis, we’ve also done a serial of experiments on Markov border inference of GMs for white box analysis and give theoretical results. Extended Bayesian Information Criterion(EBIC) The ordinary Bayes information criterion is too liberal for model selection when the model space is large. In this article, we re-examine the Bayesian paradigm for model selection and propose an extended family of Bayes information criteria. The new criteria take into account both the number of unknown parameters and the complexity of the model space. Their consistency is established, in particular allowing the number of covariates to increase to in nity with the sample size. Their performance in various situations is evaluated by simulation studies. It is demonstrated that the extended Bayes information criteria incur a small loss in the positive selection rate but tightly control the false discovery rate, a desirable property in many applications. The extended Bayes information criteria are extremely useful for variable selection in problems with a moderate sample size but a huge number of covariates, especially in genome-wide association studies, which are now an active area in genetics research. Some keywords: Bayesian paradigm; Consistency; Genome-wide association study; Tour- nament approach; Variable selection. Extended Fourier Amplitude Sensitivity Test Excluding irrelevant features in a pattern recognition task plays an important role in maintaining a simpler machine learning model and optimizing the computational efficiency. Nowadays with the rise of large scale datasets, feature selection is in great demand as it becomes a central issue when facing high-dimensional datasets. The present study provides a new measure of saliency for features by employing a Sensitivity Analysis (SA) technique called the extended Fourier amplitude sensitivity test, and a well-trained Feedforward Neural Network (FNN) model, which ultimately leads to the selection of a promising optimal feature subset. Ideas of the paper are mainly demonstrated based on adopting FNN model for feature selection in classification problems. But in the end, a generalization framework is discussed in order to give insights into the usage in regression problems as well as expressing how other function approximate models can be deployed. Effectiveness of the proposed method is verified by result analysis and data visualization for a series of experiments over several well-known datasets drawn from UCI machine learning repository. Extended Kalman Filter(EKF) In estimation theory, the extended Kalman filter (EKF) is the nonlinear version of the Kalman filter which linearizes about an estimate of the current mean and covariance. In the case of well defined transition models, the EKF has been considered the de facto standard in the theory of nonlinear state estimation, navigation systems and GPS. Extended Space Forest The Extended Space Forest is a new method for decision tree construction in which training is done with input vectors including all the original features and their random combinations. The combinations are generated with a difference operator applied to random pairs of original features. The experimental results show that extended space versions of ensemble algorithms have better performance than the original ensemble algorithms. To investigate the success dynamics of the Extended Space Forest, the individual accuracy and diversity creation powers of ensemble algorithms are compared. The Extended Space Forest creates more diversity when it uses all the input features than Bagging and Rotation Forest. It also results in more individual accuracy when it uses random selection of the features than Random Subspace and Random Forest methods. It needs more training time because of using more features than the original algorithms. But its testing time is lower than the others because it generates less complex base learners. eXtensible Neural Machine Translation toolkit(XNMT) This paper describes XNMT, the eXtensible Neural Machine Translation toolkit. XNMT distin- guishes itself from other open-source NMT toolkits by its focus on modular code design, with the purpose of enabling fast iteration in research and replicable, reliable results. In this paper we describe the design of XNMT and its experiment configuration system, and demonstrate its utility on the tasks of machine translation, speech recognition, and multi-tasked machine translation/parsing. XNMT is available open-source at https://…/xnmt Exterior Distance Function(EDF) We introduce and study exterior distance function (EDF) and correspondent exterior point method (EPM) for convex optimization. The EDF is a classical Lagrangian for an equivalent problem obtained from the initial one by monotone transformation of both the objective function and the constraints. The constraints transformation is scaled by a positive scaling parameter. Thus, the EDF is a particular realization of the Nonlinear Rescaling (NR) principle. Along with the ‘center’, the EDF has two extra tools: the barrier (scaling) parameter and the vector of Lagrange multipliers. We show that EPM generates primal – dual sequence, which converges to the primal – dual solution in value under minimum assumption on the input data. Moreover, the convergence is taking place under any fixed interior point as a ‘center’ and any fixed positive scaling parameter, just due to the Lagrange multipliers update. If the second order sufficient optimality condition is satisfied, then the EPM converges with Q-linear rate under any fixed interior point as a ‘center’ and any fixed, but large enough positive scaling parameter. Exterior Point Method(EPM) ➘ “Exterior Distance Function” Extract, Transform, Analyse and Load(ET(A)L) The ET(AL) is another form of reduction mechanism, which is why the analytics aspect is included to ensure that the data that gets through is the data that is needed, and that the junk and noise that has no recognisable value, gets cleaned out early and often. Extract-Transform-Load(ETL) In computing, extract, transform, and load (ETL) refers to a process in database usage and especially in data warehousing that: *Extracts data from outside sources *Transforms it to fit operational needs, which can include quality levels *Loads it into the end target (database, more specifically, operational data store, data mart, or data warehouse) ETL systems are commonly used to integrate data from multiple applications, typically developed and supported by different vendors or hosted on separate computer hardware. The disparate systems containing the original data are frequently managed and operated by different employees. For example a cost accounting system may combine data from payroll, sales and purchasing. Extrapolation Compression Optimizing distributed learning systems is an art of balancing between computation and communication. There have been two lines of research that try to deal with slower networks: {\em quantization} for low bandwidth networks, and {\em decentralization} for high latency networks. In this paper, we explore a natural question: {\em can the combination of both decentralization and quantization lead to a system that is robust to both bandwidth and latency?} Although the system implication of such combination is trivial, the underlying theoretical principle and algorithm design is challenging: simply quantizing data sent in a decentralized training algorithm would accumulate the error. In this paper, we develop a framework of quantized, decentralized training and propose two different strategies, which we call {\em extrapolation compression} and {\em difference compression}. We analyze both algorithms and prove both converge at the rate of $O(1/\sqrt{nT})$ where $n$ is the number of workers and $T$ is the number of iterations, matching the {\rc convergence} rate for full precision, centralized training. We evaluate our algorithms on training deep learning models, and find that our proposed algorithm outperforms the best of merely decentralized and merely quantized algorithm significantly for networks with {\em both} high latency and low bandwidth. Extremal Depth(ED) We propose a new notion called extremal depth’ (ED) for functional data, discuss its properties, and compare its performance with existing concepts. The proposed notion is based on a measure of extreme outlyingness’. ED has several desirable properties that are not shared by other notions and is especially well suited for obtaining central regions of functional data and function spaces. In particular: a) the central region achieves the nominal (desired) simultaneous coverage probability; b) there is a correspondence between ED-based (simultaneous) central regions and appropriate point-wise central regions; and c) the method is resistant to certain classes of functional outliers. The paper examines the performance of ED and compares it with other depth notions. Its usefulness is demonstrated through applications to constructing central regions, functional boxplots, outlier detection, and simultaneous confidence bands in regression problems. Extreme Bounds Analysis(EBA) The basic idea of extreme bounds analysis is quite simple. We are interested in finding out which variables from the set X are robustly associated with the dependent variable y. To do so, we run a large number of regression models. Each has y as the dependent variable and includes a set of standard explanatory variables F that are included in each regression model. In addition, each model includes a different subset D of the variables in X. Following the convention in the literature, we will refer to F as the free variables and to X as the doubtful variables. Some subset of the doubtful variables X might be socalled focus variables that are of particular interest to the researcher. The doubtful variables 4 ExtremeBounds: Extreme Bounds Analysis in R whose regression coefficients retain their statistical significance in a large enough proportion of estimated models are declared to be robust, whereas those that do not are labelled fragile. ExtremeBounds Extreme Function Theory We introduce an extreme function theory as a novel method by which probabilistic novelty detection may be performed with functions, where the functions are represented by time-series of (potentially multivariate) discrete observations. We set the method within the framework of Gaussian processes (GP), which offers a convenient means of constructing a distribution over functions. Whereas conventional novelty detection methods aim to identify individually extreme data points, with respect to a model of normality constructed using examples of ‘normal’ data points, the proposed method aims to identify extreme functions, with respect to a model of normality constructed using examples of ‘normal’ functions, where those functions are represented by time-series of observations. The method is illustrated using synthetic data, physiological data acquired from a large clinical trial, and a benchmark time-series dataset. Extreme Gradient Boosting Extreme Gradient Boosting, which is an efficient implementation of gradient boosting framework. xgboost Extreme Learning Machine(ELM) Extreme learning machine (ELM) is a modification of single layer feedforward network (SLFN) where learning is quite similar to the reservoir computing. ELMR Extreme Machine Learning(ELM) ➘ “Extreme Learning Machine” Extreme Multi-Label Learning using Distributional Semantics(ExMLDS) We present a novel and scalable label embedding framework for large-scale multi-label learning a.k.a ExMLDS (Extreme Multi-Label Learning using Distributional Semantics). Our approach draws inspiration from ideas rooted in distributional semantics, specifically the Skip Gram Negative Sampling (SGNS) approach, widely used to learn word embeddings for natural language processing tasks. Learning such embeddings can be reduced to a certain matrix factorization. Our approach is novel in that it highlights interesting connections between label embedding methods used for multi-label learning and paragraph/document embedding methods commonly used for learning representations of text data. The framework can also be easily extended to incorporate auxiliary information such as label-label correlations; this is crucial especially when there are a lot of missing labels in the training data. We demonstrate the effectiveness of our approach through an extensive set of experiments on a variety of benchmark datasets, and show that the proposed learning methods perform favorably compared to several baselines and state-of-the-art methods for large-scale multi-label learning. Extreme Studentized Deviate(ESD) The generalized extreme Studentized deviate (ESD) test is used to detect one or more outliers in a univariate data set that follows an approximately normal distribution. The primary limitation of the Grubbs test and the Tietjen-Moore test is that the suspected number of outliers, k, must be specified exactly. If k is not specified correctly, this can distort the conclusions of these tests. On the other hand, the generalized ESD test only requires that an upper bound for the suspected number of outliers be specified. Given the upper bound, r, the generalized ESD test essentially performs r separate tests: a test for one outlier, a test for two outliers, and so on up to r outliers. Extreme Value Analysis(EVA) ➘ “Extreme Value Theory” Introduction to Extreme Value Analysis https://…/Extremes.pdf hkevp,revdbayes,threshr Extreme Value Learning(EVL) The novel unseen classes can be formulated as the extreme values of known classes. This inspired the recent works on open-set recognition \cite{Scheirer_2013_TPAMI,Scheirer_2014_TPAMIb,EVM}, which however can have no way of naming the novel unseen classes. To solve this problem, we propose the Extreme Value Learning (EVL) formulation to learn the mapping from visual feature to semantic space. To model the margin and coverage distributions of each class, the Vocabulary-informed Learning (ViL) is adopted by using vast open vocabulary in the semantic space. Essentially, by incorporating the EVL and ViL, we for the first time propose a novel semantic embedding paradigm — Vocabulary-informed Extreme Value Learning (ViEVL), which embeds the visual features into semantic space in a probabilistic way. The learned embedding can be directly used to solve supervised learning, zero-shot and open set recognition simultaneously. Experiments on two benchmark datasets demonstrate the effectiveness of proposed frameworks. Extreme Value Theory(EVT) Extreme value theory (EVT) or extreme value analysis (EVA) is a branch of statistics dealing with the extreme deviations from the median of probability distributions. It seeks to assess, from a given ordered sample of a given random variable, the probability of events that are more extreme than any previously observed. Extreme value analysis is widely used in many disciplines, such as structural engineering, finance, earth sciences, traffic prediction, and geological engineering. For example, EVA might be used in the field of hydrology to estimate the probability of an unusually large flooding event, such as the 100-year flood. Similarly, for the design of a breakwater, a coastal engineer would seek to estimate the 50-year wave and design the structure accordingly. | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.6027976870536804, "perplexity": 1119.737046579642}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.3, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2018-26/segments/1529267864172.45/warc/CC-MAIN-20180621133636-20180621153636-00307.warc.gz"} |
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## Yttrium Group Title Can somebody explain me the sense of using the Baye's Law of probability and the total probability theorem? Thanks. 8 months ago 8 months ago Edit Question Delete Cancel Submit
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Suppose you have a tree of possible events like the one below: |dw:1385668006646:dw| Then, Baye's law says that the probability of one event on the far right (say $$\alpha$$), given that one of the preliminary events (say $$A$$) has occurred, is given by $P(\alpha|A)=\frac{P(A|\alpha)P(\alpha)}{P(A)}=\frac{P(A|\alpha)P(\alpha)}{P(A|\alpha)+P(A|\beta)+P(A|\Gamma)}$ Basically, it says that the probability of some event $$A$$ occurring, given the occurrence of another event $$\alpha$$, is given by the ratio of (1) [the probability of $$A$$ and $$\alpha$$ occurring together] to (2) [the total probabilities of $$A$$ occurring]. (1) The probability of two events occurring together is $$P(A\cap\alpha)$$. Using the conditional probability definition, we get $$P(A|\alpha)=\dfrac{P(A\cap\alpha)}{P(\alpha)}$$, i.e. $$P(A\cap\alpha)=P(A|\alpha)P(\alpha)$$. (2) The total probability theorem is another way of saying that the denominators in the above equation are the same.
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Thanks for being so helpful in mathematics. If you are getting quality help, make sure you spread the word about OpenStudy. | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 1, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9905089735984802, "perplexity": 1935.0264953703058}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2014-23/segments/1405997888216.78/warc/CC-MAIN-20140722025808-00143-ip-10-33-131-23.ec2.internal.warc.gz"} |
https://rpg.stackexchange.com/questions/28409/how-would-i-run-a-game-of-legend-without-a-battlemap | # How would I run a game of Legend without a Battlemap?
Since both battle-mats and miniatures tend to be fairly expensive (and I would personally prefer a more descriptive style of battles anyway), I was wondering how one might run a game of Legend without using a mat while maintaining the same level of balance (or roughly the same level of balance). I understand that quite a bit of the game has to do with ranges and AoE spreads (melee range expanding being one of the big ones). Is there a way to run Legend without a battle-grid while keeping the same tactical charm?
• The question doesn't mention cheap alternatives to minis and vinyl or preprinted battle maps: is that an oversight or are they unacceptable? – SevenSidedDie Aug 31 '13 at 19:50
• I would personally prefer more descriptive style battles aside from cost concerns; however, any cheap alternatives would definitely be helpful and worthwhile for running a game if a descriptive style game isn't possible. – WrongOnTheInternet Aug 31 '13 at 19:53
• Cool. That's a totally valid preference, and I've added it to the question to prevent answerers from assuming they can quickly solve your problem by side-stepping it and offering cheaper grid/mini options. – SevenSidedDie Aug 31 '13 at 19:58
I have played DnD (which is extremely similar to Legend when it comes to combat) both with grids and without grids. Here is some advice I hope you will find useful. As you prefer to play descriptively (i.e. without map) rather than with map, I will start there.
## Playing without a grid
When I have improvised games far from home, I have never had a grid or anything like that. In these situations you can still play and retain most of the tactical flavour as long as everybody is happy trading flexibility for accuracy.
Draw the map on a piece of paper and tell people where they are and where the enemies are. You can even write/draw on a photocopy of a map that you have printed/photocopied. If you have small objects (dice, pen caps, LEGO people...) to be the characters, all the better; otherwise, pencil and eraser works fine (I have even done it with just a pen; it quickly becomes messy, but it is OK as long as your players are happy to play cool instead of arguing every position and every movement).
The rule of thumb is "if in doubt, make it cool". Without a grid you can never be sure whether a movement produces an attack of opportunity, what the range is, whether the AoE affects all the enemies... but you gain flexibility for the story.
Use your judgement to see how far a character can move, whether they can dodge their enemies, and who is affected by areas of effect. If in doubt, make it fun. If a PC wants to use their new ability but it is unclear whether they can or not because of their position ("am I adjacent to the orc chieftain?"), say they can. If it is unclear whether the fireball wipes out all the goblins, say it does (unless you think it is funnier to wipe out only half).
Final word: If you have very nitpicky / rules-lawyering players, maybe it is better to play with a grid to avoid arguments. Arguments are not fun for anybody except the arguing person.
An now for something completely different...
## Playing with a grid (without breaking the bank)
To enjoy the full tactical depth of some games, you really need a grid. Here is some advice to make it cheap.
I used to use a table cover made of transparent plastic. This can be found in many supermarkets and most hardware stores and is really cheap. Then you can draw the 1-inch grid on the "down" side with a ruler and a permanent marker.
To use the grid just put the table cover on top of the table. You can draw on it on the "up" side with whiteboard markers. It is easy to erase the map with a cloth for the next session / combat because the grid and the map are on opposite sides. For extra simplicity, you can print or photocopy the map and put it under the table cover and then you do not have to draw anything: it is right there.
For the characters (both PC and NPC) use anything you have handy: dice, balls of crumpled paper, pen caps, LEGO people... or just draw them as crosses with the whiteboard markers. In my experience, most players are OK with this and the game flows well. Of course the minis are very cool, but I agree that they can become an expensive hobby. ;-)
• The comments (and the edited title) make now clear that the OP has a preference for "playing without battlemap" rather than "cheap options for a battlemap", so I have edited the question accordingly. – sergut Sep 2 '13 at 11:56
• I like this answer quite a bit. For people who don't fight over whether or not something was inside or outside an area of effect (by one whole square), the top method is good. The plastic table idea is certainly helpful as well. – WrongOnTheInternet Sep 2 '13 at 18:19
• Unless you're comparing it to 4e, this is off. Legend and D&D 3.5e have some significant differences in how important the grid is. In particular, 3.xe was designed explicitly to have the grid be optional. – SevenSidedDie Sep 3 '13 at 16:09
I don't think Legend can be played without a grid. Some circles require you to think in terms of squares and the whole tactical game revolves around getting into position in a way that's better not to handwave.
Another option could be 1-inch-gridded sheets of paper, with maps pre-drawn directly on them after the gaming session, with tokens or small paperfold figures to represent characters. (Strips of paper folded this way: _/\_ ) | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.348923921585083, "perplexity": 1394.802013910631}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2019-39/segments/1568514577363.98/warc/CC-MAIN-20190923150847-20190923172847-00549.warc.gz"} |
https://socratic.org/questions/57bdc9167c014969e900962d | Chemistry
Topics
# How do I convert "35.0 yd" to "nm"?
##### 1 Answer
Aug 24, 2016
I got $3.20 \times {10}^{10} \text{nm}$.
You can go about it in more than one way; it depends on which conversion factors you know best. I would recommend that you use the ones you definitely remember.
The general pathway I would approach it is:
$\cancel{\text{yd" xx cancel"ft"/cancel"yd" xx cancel"in"/cancel"ft" xx cancel"cm"/cancel"in" xx cancel"m"/cancel"cm" xx "nm"/cancel"m}}$
So, the conversion factors we will use are:
• $\text{3 ft}$ in one $\text{yd}$
• $\text{12 in}$ in one $\text{ft}$
• $\text{2.54 cm}$ in one $\text{in}$
• One $\text{m}$ in $\text{100 cm}$
• ${10}^{9} \text{nm}$ in one $\text{m}$
Therefore, we get:
$35.0 \cancel{\text{yd" xx (3 cancel"ft")/cancel"yd" xx (12 cancel"in")/cancel"ft" xx (2.54 cancel"cm")/cancel"in}}$
$\times \cancel{\text{m"/(100 cancel"cm") xx (10^9"nm")/cancel"m}}$
$= \textcolor{b l u e}{3.20 \times {10}^{10} \text{nm}}$
You keep three significant figures because all of these conversion factors are exact, and the measurement is known to a specific uncertainty (by default, $\pm 0.1$).
So, your answer has $3$ significant figures.
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https://www.physicsforums.com/threads/particle-motion-in-space.819413/ | # Particle Motion in Space
1. Jun 17, 2015
### RyanH42
1. The problem statement, all variables and given/known data
A particle moves so that its equation of motion in vector form given is given by $\vec{R}=((sint^-1)/2+t/2√(1-t^2))\vec{i}+1/2t^2\vec{j}$ , $0≤t<1$
a)Show that particle moves with a constant speed.
b)Compute $\vec{v}$ and $\vec{a}$,and verify that $\vec{v}$.$\vec{a}$=0 (dot product).(As it should be when speed is constant
c)Since the magnitude of speed is constant ,must the magnitude of acceleration also be constant ?
2. Relevant equations
$\vec{v}=d\vec{R}/dt$
$\vec{a}=d\vec{v}/dt$
3. The attempt at a solution
For a), I have to do $\vec{v}=d\vec{R}/dt$ and then I have to do this $\|\vec{v}\|$.If $\|\vec{v}\|$ this do not contain t it means $\|\vec{v}\|$ is constant
For c)$\vec{v}$.$\vec{a}$=0 this means $\|\vec{v}\|.\|\vec{a}\|.cosθ=0$ we know that $\|\vec{v}\|$ is not zero so theres two option 1) $\|\vec{a}\|$ will be zero or $cosθ$ will be $0$.If $cosθ$ is zero then theres no need to be constant magnitude of $\vec{a}$.I think answer is no.Theres a chance to be not constant.
Is my answers are true ?
Thanks
2. Jun 17, 2015
### ecastro
I think 'c' is a conceptual question. You don't need any form of equation to answer the question.
3. Jun 17, 2015
### RyanH42
4. Jun 17, 2015
### haruspex
Your reasoning for c) is good.
I can't comment on a) and b) because I'm not sure what the given equation for R is saying, but you appear happy with your answers to those.
5. Jun 17, 2015
### ecastro
Sorry about that. Here, to clear things up.
a.) Yes, this is correct. The velocity of the particle is constant if the first derivative of your position vector is constant, or if its second derivative is zero (both with respect to time).
c.) This is conceptual if you consider the question for general cases, that is, for all position vectors with a constant velocity. However, if the question is only for this problem in particular, you can calculate $\theta$.
6. Jun 18, 2015
### RyanH42
Ok,I get the idea.I can calculate the $cosθ$ Actually question b is asked for that I guessThanks for help.
Draft saved Draft deleted
Similar Discussions: Particle Motion in Space | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9824219346046448, "perplexity": 740.2665321116311}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 5, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2017-39/segments/1505818689823.92/warc/CC-MAIN-20170924010628-20170924030628-00345.warc.gz"} |
https://tapir.softwaremill.com/en/latest/client/sttp.html | # Using as an sttp client
"com.softwaremill.sttp.tapir" %% "tapir-sttp-client" % "1.0.4"
To make requests using an endpoint definition using the sttp client, import:
import sttp.tapir.client.sttp.SttpClientInterpreter
This objects contains a number of variants for creating a client call, where the first parameter is the endpoint description. The second is an optional URI - if this is None, the request will be relative.
Here’s a summary of the available method variants; R are the requirements of the endpoint, such as streaming or websockets:
• toRequest(PublicEndpoint, Option[Uri]): returns a function, which represents decoding errors as the DecodeResult class.
I => Request[DecodeResult[Either[E, O]], R]
After providing the input parameters, a description of the request to be made is returned, with the input value encoded as appropriate request parameters: path, query, headers and body. This can be further customised and sent using any sttp backend. The response will then contain the decoded error or success values (note that this can be the body enriched with data from headers/status code).
• toRequestThrowDecodeFailures(PublicEndpoint, Option[Uri]): returns a function, which will throw an exception or return a failed effect if decoding of the result fails
I => Request[Either[E, O], R]
• toRequestThrowErrors(PublicEndpoint, Option[Uri]): returns a function, which will throw an exception or return a failed effect if decoding of the result fails, or if the result is an error (as described by the endpoint)
I => Request[O, R]
Next, there are toClient(PublicEndpoint, Option[Uri], SttpBackend[F, R]) methods (in the above variants), which send the request using the given backend. Hence in this case, the signature of the result is:
I => F[DecodeResult[Either[E, O]]]
Finally, for secure endpoints, there are toSecureClient and toSecureRequest families of methods. They return functions which first accept the security inputs, and then the regular inputs. For example:
// toSecureRequest(Endpoint, Option[Uri]) returns:
A => I => Request[DecodeResult[Either[E, O]], R]
// toSecureClient(Endpoint, Option[Uri], SttpBackend) returns:
A => I => F[DecodeResult[Either[E, O]]]
See the runnable example for example usage.
## Web sockets
To interpret a web socket endpoint, an additional streams-specific import is needed, so that the interpreter can convert sttp’s WebSocket instance into a pipe. This logic is looked up via the WebSocketToPipe implicit.
The required imports are as follows:
import sttp.tapir.client.sttp.ws.akkahttp._ // for akka-streams
import sttp.tapir.client.sttp.ws.fs2._ // for fs2
import sttp.tapir.client.sttp.ws.zio._ // for zio 2.x
import sttp.tapir.client.sttp.ws.zio1._ // for zio 1.x
No additional dependencies are needed (except for zio1, which needs the tapir-sttp-client-ws-zio1 dependency), as both of the above implementations are included in the main interpreter, with dependencies on akka-streams, fs2 and zio being marked as optional (hence these are not transitive).
## Overwriting the response specification
The Request obtained from the .toRequest and .toSecureRequest families of methods, after being applied to the input, contains both the request data (URI, headers, body), and a description of how to handle the response - depending on the variant used, decoding the response into one of endpoint’s outputs.
If you’d like to skip that step, e.g. when testing redirects, it’s possible to overwrite the response handling description, for example:
import sttp.tapir._
import sttp.tapir.client.sttp.SttpClientInterpreter
import sttp.client3._
SttpClientInterpreter()
.toRequest(endpoint.get.in("hello").in(query[String]("name")), Some(uri"http://localhost:8080"))
.apply("Ann")
.response(asStringAlways)
## Scala.JS
In this case add the following dependencies (note the %%% instead of the usual %%):
"com.softwaremill.sttp.tapir" %%% "tapir-sttp-client" % "1.0.4"
"io.github.cquiroz" %%% "scala-java-time" % "2.2.0" // implementations of java.time classes for Scala.JS
The client interpreter also supports Scala.JS, the request must then be sent using the sttp client Scala.JS Fetch backend.
You can check the SttpClientTests for a working example.
## Limitations
There are limitations existing on some clients that prevent the description generated by tapir from being decoded correctly. For security reasons the Set-Cookie header is not accessible from frontend JavaScript code.
It means that any endpoint containing a .out(setCookie("token")) will fail to be decoded on the client side when using Fetch. A solution is to use the setCookieOpt function instead an let the browser do its job when dealing with cookies. | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.18053016066551208, "perplexity": 7310.844358947278}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2022-33/segments/1659882571538.36/warc/CC-MAIN-20220812014923-20220812044923-00673.warc.gz"} |
https://www.springermedizin.de/strengthening-preventive-care-programs-a-permanent-challenge-for/9485402?fulltextView=true&doi=10.1186%2F1471-2458-10-417 | main-content
01.12.2010 | Research article | Ausgabe 1/2010 Open Access
# Strengthening preventive care programs: a permanent challenge for healthcare systems; lessons from PREVENIMSS México
Zeitschrift:
BMC Public Health > Ausgabe 1/2010
Autoren:
Gonzalo Gutiérrez, Ricardo Pérez-Cuevas, Santiago Levy, Hortensia Reyes, Benjamín Acosta, Sonia Fernández Cantón, Onofre Muñoz
Wichtige Hinweise
## Electronic supplementary material
The online version of this article (doi:10.1186/1471-2458-10-417) contains supplementary material, which is available to authorized users.
## Competing interests
The authors declare that they have no competing interests.
## Authors' contributions
GG, OM and SL contributed in developing the PREVENIMSS program; GG, HR, BA and SFC developed and conducted the surveys and carried out the statistical analysis of ENCOPREVENIMSS. RPC and HRM conceptualized and wrote the paper. All authors critically edited the manuscript, participated in the interpretation of data and read and approved the final version.
## Background
It has been a long-standing fact that curative care receives most of the healthcare budgets [ 1]; however, preventive care is receiving further attention from scholars, politicians and decision makers given its effectiveness on people's health and its long-term effect on social expectancies and well-being [ 2] Current emphasis has shifted toward cost-effective delivery of healthcare [ 3] which implies finding equilibrium between curative and preventive care through reinforcing primary care services [ 4]. The World Health Organization is a strong advocate to renew primary health care (PHC) pointing out that it is the cornerstone of health systems and is the best way to provide comprehensive, equitable and affordable health care. Preventive care is within the main components of PHC and when the provision is comprehensive, it increases the access and uptake of preventive services, which in turn contributes to obtain better health and improved quality [ 5] Providing preventive services within PHC facilitate to obtain both, technical and productive efficiency. A number of technical documents have stressed the importance of prioritizing health interventions to better allocate the scarce resources [ 610].
The Instituto Mexicano del Seguro Social (IMSS) is the largest public healthcare system in Mexico. It is a nationwide institution that administratively is divided in state delegations. IMSS provides social, economic and health protection to workers of the formal sector and their families. The workers of the formal sector are those employed with regular wages and hours, with employment rights and tax payments. Its members work in the industry and in the services sector such as commerce, transportation, etc. [ 11] IMSS provides services in urban areas and almost all of its members have basic sanitary conditions (water, electricity, sewerage, etc.).
Healthcare benefits comprise preventive, curative and rehabilitation care that is provided in primary care clinics, secondary and tertiary care hospitals. IMSS revenues come from three parties: the government, the employers and the employees. The latter pay the premium according to their income.
Currently, IMSS provides care to approximately 48 million members. Since the year 2000, this institution reoriented its vision regarding the provision of medical care and began to search for an appropriate balance in its healthcare expenditures for both curative and preventive care. In 2007, chronic conditions such as type 2 diabetes, hypertension, chronic renal failure, cervical cancer, breast cancer and HIV/AIDS accounted for 12.15% of the total IMSS healthcare expenditures. The projections for the year 2050, using an optimistic scenario that includes the strengthening of preventive measures and technological innovation, estimated that the percentage of IMSS healthcare expenditures for these seven conditions would be 22% and the pessimistic scenario (not investing in preventive and curative care) estimated an increase of 57% in health expenditures [ 11].
To strengthen preventive care, IMSS carried out a situation analysis of the way in which these services were provided. The analysis showed: 1) lack of coordination to provide preventive care. There were > 30 isolated preventive programs (i.e., vaccination program, family planning program, cervical cancer screening program, and so on). These programs were competing among themselves for resources and personnel; 2) gaps in the health information system that was unable to provide exact figures regarding its coverage. To tackle these flaws, the institution developed the program PREVENIMSS (the Spanish acronym for IMSS' Integrated Preventive Care Program) that aimed at improving the delivery of service, and at evaluating the progress of coverage of preventive care services. The usual definition of coverage is the regular update of the proportion of individuals who need an intervention and actually receive it; therefore, information about coverage is key to evaluate health programs.
Three strategies integrated the organizational changes supporting the implementation of this program: (1) Integration of the scattered preventive activities into a comprehensive package. (2) Reorientation of evaluation criteria, shifting from evaluation of productivity to evaluation of coverage. IMSS launched PREVENIMSS in 2001 and this was accompanied by a permanent mass media campaign with radio and television advertisements. A careful description of PREVENIMSS has been published elsewhere [ 12].
1. Integration of preventive services. PREVENIMSS reorganized the provision of preventive services by programmatic age groups: children (0-9 years), adolescents (10-19 years), women (20-59 years), men (20-59 years) and older adults (60 years and older). A number of organizational and procedural changes took place at central, district and local level. The old appointment booklets for IMSS individual members were redesigned to include preventive information, dated registries of preventive services, and reminders tailored to suit each programmatic age group. The booklet is the official document where preventive services are being registered each time that an IMSS member receives preventive care at IMSS facilities. Thus, the booklet contains registries about vaccines, screening and educational activities. It also registers the appointments to provide programmed preventive services. Each IMSS member has his/her individual booklet.
Preventive services for each age group were reviewed and updated continuously. Table 1 shows the preventive services for each age group. The broad areas of preventive services were: health promotion, nutrition, prevention, control and screening of selected diseases.
Table 1
PREVENIMSS main activities by age group
Activities
Children
Women
Men
0-10 years
11 -19 years
20-59 years
20-59 years
> = 60 years
Health promotion
Delivery of PREVENIMSS booklets
Measurement of height, weight and waist
Nutrition
Iron supplementation
Vitamin A supplementation
Intestinal parasites treatment
Intestinal parasites treatment
Folic acid supplementation (pregnant teenagers)
Detection of anemia; iron supplementation; folic acid supplementation (pregnant women)
Prevention and control of diseases
Vaccines: BCG, Sabin; DPT+HB+Hlb; Influenza; measles, rubella, pertussis,
Oral rehydration therapy for acute diarrhea, identification of alarm signs in acute respiratory infections
Vaccines: measles-rubella, tetanus toxoid, two-dose hepatitis B,
Provision of condoms to prevent STDs and HIV/AIDS and unwanted pregnancies
Vaccines: measles-rubella, tetanus toxoid, diphtheria
Tuberculosis: screening and directly observed treatment
Vaccines: measles-rubella, tetanus toxoid.
Tuberculosis: screening and directly observed treatment
Vaccines: pneumonia, influenza, tetanus toxoid and diphtheria;
Tuberculosis: screening and directly observed treatment
Screening
Congenital hypothyroidism,
Phenylketonuria.
Biotinidase deficiency,
Visual acuity,
Childhood caries
Visual acuity
Cervical cancer
Breast cancer
Type 2 diabetes
Hypertension
Type 2 diabetes
Hypertension
Cervical cancer
Breast cancer
Type 2 diabetes
Hypertension
Reproductive health
Family planning and antenatal care
Family planning
2. Reorientation of evaluation criteria. The former criterion to evaluate the progress of preventive actions was productivity; the criteria were reoriented to evaluate coverage. The registries of productivity served only to ascertain the number of preventive actions provided; no denominator was used for this measure. Instead, for coverage, criteria to receive a preventive action were defined to meet the health needs of the affiliated population; i.e., immunization schemes according to age and dose, or periodicity of cervical cancer screening based upon risk factors. This decision helped to focus the provision of preventive actions based in actual health needs rather than in the percentage of people receiving preventive services.
With the aim of showing the complexity of implementing large scale preventive care programs to reinforce PHC, the objective of this paper is to describe the increase of coverage of preventive actions through the PREVENIMSS program and the magnitude of the unmet needs of some of the most important unsolved and emergent health problems, such as anemia in children, and the growing increase in the prevalence of overweight and obesity and of its consequences, type 2 diabetes and hypertension.
## Methods
The evaluation of PREVENIMSS' coverage was conducted through four population surveys that were carried out in the years 2003, 2004, 2005 and 2006. These surveys were called ENCOPREVENIMSS for its Spanish acronym: PREVENIMSS National Coverage Surveys. All four nation-wide cross sectional surveys were designed as probabilistic, population-based. The study population was all IMSS members across the country. IMSS considers as a member a person who is entitled to receive social security services within which healthcare is included; this comprises the insured and their beneficiaries (spouse, children, and parents).
The information of preventive care was obtained through home interviews and included all IMSS members living in the house, whether or not they had used IMSS services or looked for care in other healthcare institutions, either public or private. The answers provided by the interviewee were confirmed by reviewing the information registered at the PREVENIMSS booklet.
The surveys had ethical approval from the IMSS Institutional Review Board. All participants received information about the purpose of the study and were asked for their informed consent before starting the interview. To collect information from children, the mother or caretaker should have to provide her informed consent.
### Sampling design
The sampling design took into account that IMSS is divided into 37 state delegations. The surveys were planned to be representative in every state delegation for each programmatic age group. A four-stage sampling design was used. In the first stage, six family medicine clinics all belonging to the IMSS health care system were randomly chosen at each state delegation; this represented a total of 222 family medicine clinics. At the second stage, the geographic area of influence of each family medicine clinic was considered; then, a portion of this area was randomly chosen. At the third stage, a specific neighborhood was randomly selected. The fourth stage consisted in identifying the households where IMSS members were living; the interviewers did home visits looking for IMSS members. The interviewers were up to three times to the house to contact the potential participant. If the interviewers were unable to contact the residents of the selected household or if they refused to participate, then, the household was replaced with another with similar characteristics.
The primary sampling unit was the household and the elementary unit was the IMSS member. We interviewed all household members entitled to receive IMSS services. This is because IMSS policy consists in providing health care to the worker and his/her family dependants.
To get the estimates of coverage per programmatic age group, the sample size for the surveys was calculated using the following formula:
$n = pq [ ( Z ∝ / 2 ) 2 δ 2 ] DEFT 1 − NR$
Assumptions: n = sample size, p = proportion of coverage (0.6), q = 1-p, α = 0.05, δ = 0.05, design effect (DEFT) = 1.2, and non-response rate (NR) = 10%.
In the first survey (2003) the proportion of coverage (p) was estimated to be 0.8. Thus the n for this survey was lower than for the surveys of the years 2004, 2005 and 2006.
The resulting sample size was 492 participants in each programmatic age group per state delegation. The total sample size per delegation was 2,460, which multiplied by the 37 state delegations resulted in ~91,000 individuals in each survey.
Sources of information and main variables
The PREVENIMSS booklet was the main source of information and as mentioned earlier, physical measures were taken in a subsample of interviewees for the 2006 survey.
The main variables in each programmatic age group were:
Children (0-9 years): registry of height and weight, iron supplementation, oral health activities, visual acuity measurement and vaccines scheme.
Adolescents: (10-19 years): registry of height and weight, oral health activities, visual acuity measurement, vaccines scheme and use of condoms.
Women (20-59 years): registry of height, weight and waist, screening for tuberculosis, cervical cancer, breast cancer, type 2 diabetes and hypertension.
Men (20-59 years): registry of height, weight and waist, screening for tuberculosis, type 2 diabetes and hypertension.
Older adults (60 years and older): registry of height, weight and waist, pneumococcal vaccine, influenza vaccine, screening of tuberculosis, cervical cancer (women), breast cancer (women), type 2 diabetes and hypertension.
Sociodemographic variables: age, sex, place of residence, literacy of individuals 5 years and older, occupation and size of the family (defined as the number of people living in the house).
In the 2006 survey, to complement the information, we took physical measures to estimate the prevalence of several conditions (unmet health needs). To obtain the information to estimate the prevalence of malnutrition, overweight and obesity, the interviewers measured height, weight, waist and hip circumferences to 25% of all interviewees. The interviewers were nurses that were previously trained and standardized to measure weight and height. All were independent from IMSS and hired for this survey.
The levels of cholesterol and blood glucose were measured in 25% of interviewees that were above 19 years old. The Accutrend ® GCT, Roche was used for this purpose.
The levels of hemoglobin to ascertain anemia were measured in 25% of children below 5 years. We used the B-hemoglobin photometer (HemoCue ®, Ångelholm, Sweden) for this purpose.
Blood pressure measurements to 25% of interviewees older than 19 years were taken by using sphygmomanometers (TJX MD 3000).
Criteria to ascertain overweight and obesity were as follows:
• Children less than five years old: overweight, body mass index (BMI) between 2-3 Z score; obesity, > 3 Z score of WHO growth standard [ 13]
• Children 5 to 9 years: overweight and obesity BMI criteria of International Obesity Task Force [ 14]
• Adolescents: Overweight and obesity, BMI criteria of International Obesity Task Force [ 14]
• Women, men and older adults: overweight, BMI 25 to 29.9; obesity, BMI > = 30 [ 15]
Criteria for type 2 diabetes screening: fasting glucose ≥ 126 mg/dl; casual glucose ≥ 200 mg/dl.
Criteria for hypertension: systolic blood pressure ≥ 140 mm Hg in two subsequent measurements or diastolic blood pressure ≥ 90 mm Hg in two subsequent measurements in the same visit, at the beginning and at the end of the visit.
### Data analysis
The statistical analysis included the ascertainment of the proportion of IMSS members who received preventive services. This was evaluated according to each programmatic age group. The increase of coverage throughout the years was estimated by comparing the groups of subjects per age group, year and type of preventive care. The slopes were compared by running a simple regression analysis, and the assessment of the goodness of fit was done by calculating the correlation coefficients (r 2) [ 16].
## Results
### Population Characteristics
The number of IMSS members interviewed ranged from 79,797 respondents in 2003 to 117,036 respondents in 2006. Table 2 shows the age distribution of the people interviewed. The age distribution corresponds fairly with the sample design and it should not be considered representative of the age distribution of IMSS members. The individual non-response rate in the four surveys was below 10%.
Table 2
Households and population respondents. ENCOPREVENIMSS 2003-2006
2003
2004
2005
2006
Households with IMSS members
34,610
37,877
44,278
40,682
Population respondents
No.
%
No.
%
No.
%
No.
%
Children (< 10 years)
15,289
19.2
20,762
17.6
23,177
18.9
22,365
19.1
Teenagers (10 to 19 years)
13,356
16.7
20,259
17.2
21,474
17.6
20,701
17.7
Women (20 to 59 years)
22,165
27.8
30,910
26.2
32,317
26.4
29,939
25.6
Men (20 to 59 years)
16,275
20.4
25,745
21.8
25,375
20.7
24,507
20.9
12,712
15.9
20,208
17.1
20,037
16.4
19,524
16.7
Total
79,797
100.0
117,884
100.0
122,380
100.0
117,036
100%
### Coverage
#### Health programs for children
Coverage of preventive programs for children increased continuously: iron supplementation in children < 1 year (17.8% to 65.5%) prevention of childhood caries (40.5% to 58.1%) screening for congenital metabolic disorders phenylketonuria, congenital adrenal hyperplasia, biotinidase deficiency (60.3% to 81.6%) and visual acuity testing (12.5% to 47.5%) (table 3).
Table 3
Coverage of preventive services provided to children and adolescents
Coverage indicators in each age group
year
Linear slope
2003
2004
2005
2006
Children
n = 15,289
n = 20,762
n = 23,177
n = 22,365
%
%
%
%
%
%
Delivery of PREVENIMSS booklets
32.1
62.7
77.2
90.7
19.0
95.5
Weight measurement
72.2
73.5
79.0
84.4
Height measurement
56.6
70.3
76.0
81.7
Iron supplementation in children < 1 year old
17.8
46.0
47.7
65.5
Completed scheme of vaccination by age
91.4
91.0
91.4
90.3
-0.3
52.1
Fluoride application
40.5
42.0
43.2
58.1
5.4
72.7
Hypothyroidism screening
97.1
96.7
98.5
98.0
0.4
49.9
Screening for congenital adrenal hyperplasia, phenylketonuria and biotinidase deficiency
--
-
60.3
81.6
21.3
100.0
Visual acuity screening
12.5
22.5
32.1
47.5
11.5
98.6
n = 13,356
n = 20,259
n = 21,474
n = 20,701
Linear slope
%
%
%
%
%
%
Delivery of PREVENIMSS booklets
25.9
54.6
68.9
84.3
19.0
97.0
Weight measurement
36.3
57.7
64.1
73.2
11.7
92.8
Height measurement
33.8
55.3
61.6
71.1
11.8
93.0
Measles-rubella vaccine
52.4
55.6
58.8
71.4
6.0
87.2
Tetanus toxoid and diphtheria vaccine
68.0
65.8
63.7
80.0
3.4
36.0
Hepatitis B vaccine
9.3
17.7
26.1
46.2
11.9
94.5
Use of condom in last intercourse
17.9
30.4
42.2
59.9
13.8
99.1
visual acuity screening
2.1
30.1
51.5
61.2
19.9
95.9
Almost all components of the adolescents program, excepting the vaccination program, were implemented right from the onset of PREVENIMSS. The activities included measurement of weight and height, vaccines: measles - rubella (52.4% to 71.4%), tetanus toxoid- diphtheria (68% to 80%) hepatitis (9.3% to 46.2%) There was also increase in the use of condoms (17.9% to 59.9%) and in visual acuity testing (2.1% to 61.2%), (Table 3).
#### Health programs for women
Measles-rubella vaccine increased from 28.5% to 59.2%, women undergoing cervical cancer screening for the first time or subsequent screening (three-year interval) increased from 66.7% to 75%. Breast cancer screening by using mastography began in 2004 and by the year 2006 its coverage was 22.1% (Table 4).
Table 4
Coverage of preventive services provided to women, men and older adults
Coverage indicators in each age group
Years
Linear slope
Women
2003
2004
2005
2006
n = 22,165
n = 30,910
n = 32,317
n = 29,939
%
%
%
%
%
%
Delivery of PREVENIMSS booklets
34.9
66.5
80.5
90.0
17.9
92.5
Weight measurement
69.7
69.5
79.0
84.9
5.5
89.3
Height measurement
51.1
61.6
74.0
80.4
10.0
98.6
Waist measurement
8.1
17.2
26.4
52.9
14.4
91.9
Measles rubella vaccine
28.5
36.2
43.9
59.2
10.0
96.6
Breast cancer screening
Clinical exam
42.6
45.3
50.4
62.4
6.5
90.2
Mastography
6.5
7.9
22.1
7.8
81.7
Cervical cancer screening
81.3
78.8
82.4
86.9
2.0
60.5
Once in the last 3 years
66.7
72.4
74.5
75.0
2.7
84.0
Once in the last year
40.6
51.0
45.1
43.3
0.2
0.4
Diabetes mellitus screening
45.3
55.1
56.8
66.5
6.5
94.3
Hypertension screening
60.6
66.0
70.6
74.2
4.5
99.2
Men
n = 16,275
n = 25,745
n = 25,375
n = 24,507
Linear slope
%
%
%
%
%
%
Delivery of PREVENIMSS booklets
25.1
55.3
70.9
85.1
19.6
96.3
Weight measurement
56.8
53.8
62
73.9
6.0
75.2
Height measurement
47.2
49.4
58.7
70.6
8.0
92.8
Waist measurement
3.8
9.7
16.6
45.1
13.1
85.2
Measles rubella vaccine
21.9
28.8
35.7
49.4
8.9
96.6
Diabetes mellitus screening
38.6
41.7
44.4
57.8
6.0
84.8
Hypertension screening
48.4
49.1
56.5
64.0
5.4
91.4
n = 12,712
n = 20,208
n = 20,037
n = 19,524
Linear slope
%
%
%
%
%
%
Delivery of PREVENIMSS booklets
49.3
75.5
84.4
92.7
13.9
91.1
Weight measurement
64.7
76.9
83.1
88.2
7.7
95.5
Height measurement
48.3
71.1
78
83.9
11.4
88.7
Waist measurement
4.5
13.7
23.5
52.9
15.5
90.9
Pneumococcal vaccine
13.2
24.4
23.6
24.9
3.4
63.1
Influenza vaccine
12.6
27
37.2
52.9
13.1
99.4
Tuberculosis vaccine
1.9
2.8
3.7
5.0
1.0
99.1
Diabetes mellitus screening
34.8
54.4
56
65.2
9.3
87.8
Hypertension screening
46.0
66.9
71.8
75.0
9.2
82.7
#### Health programs for men
Weight and height measurements increased (56.8% to 73.9% and 47.2% to 70.6% respectively), type 2 diabetes screening increased from 38.6% to 57.8% and hypertension screening increased from 48-4% to 64.0% (table 4).
#### Health programs for older adults
Pneumococcal vaccination coverage increased from 13.2% to 24.9%. Influenza vaccine coverage also increased from 12.6% to 52.9 (table 4).
The linear slopes and the r 2 linear adjustment outcomes show the strength of the linear relationship between PREVENIMSS and the increase in coverage for the different components of the program. This represents that the largest values in the table (closer to 1 or 100%) show the straight-line relationship between the program and the attained coverage figures.
### Unmet needs
Prevalence of anemia in children one to four years old (ENCOPREVENIMSS 2006): Figure 1 shows that children under one year of age had the highest prevalence (30.8%) of anemia. The level of incidence decreases progressively with age, the lowest figure being observed in children four years old (12%). The overall proportion of anemia in children 0-4 years was 19%.
Overweight, obesity, type 2 diabetes and hypertension (Figures 2 and 3): Among the most important findings of ENCOPREVENIMSS are the prevalence of overweight and obesity, type 2 diabetes and hypertension, in both diagnosed and undiagnosed cases. The prevalence of overweight and obesity in every age group was as follows: children 9.5%; adolescents 30.9%; men 61.3%; women 62.1% and older adults 69.9%. The total prevalence of type 2 diabetes was 14.8%, and 10% of the people with diabetes were unaware about their condition. One out of every four adults aged between 20 and 59 years had diabetes and the frequency of this condition increased with age. Total prevalence of hypertension was 35.6% and four out of ten people with hypertension were unaware that they had this condition. Prevalence of hypercholesterolemia was 12.8% in men, 14.6% among women and 22.1% in older adults; 75.1% were unaware about having this condition.
Geographical distribution of overweight and obesity (Table 5): To analyze this information the country was divided arbitrarily in five regions: North (States of Baja California, Baja California Sur, Coahuila, Chihuahua, Durango, Nayarit, Nuevo Leon, Sinaloa, Sonora y Tamaulipas), Center (States of Aguascalientes, Colima, Guanajuato, Hidalgo, Jalisco, Estado de Mexico, Michoacán, Morelos, Puebla, Queretaro, San Luis Potosí, Tlaxcala, Veracruz y Zacatecas), South (States of Chiapas, Guerrero y Oaxaca), Southeast (States of Campeche, Quintana Roo, Tabasco and Yucatán) and Mexico City. The wealthiest states of the country are in the North region, whereas the states of the Central and Southeast regions and Mexico City, are a mix of low, middle and upper income; while the three states of the South Region are predominantly poor.
Table 5
Prevalence of overweight and obesity in each region of the country and age group
Condition/Age group
North
Center
South
Southwest
Mexico City
National
%
%
%
%
%
%
Overweight
Children
8.1
7.1
13.6
9.6
3.7
7.5
24.2
18.3
21.4
26.2
21.7
21.3
Women
40.6
36.1
40.3
36.4
34.5
37.1
Men
48.9
42.9
48.7
47.8
36.9
44.2
44.2
41.8
41.0
43.3
43.2
42.7
Obesity
Children
2.5
1.6
4.6
2.7
0.5
2.0
11.2
8.2
11.7
15.2
5.7
9.6
Women
29.4
23.6
27.6
32.8
16.1
25.0
Men
18.2
17.3
22.5
22.8
8.2
17.1
31.4
25.3
30.5
32.1
21.0
27.2
Source: ENCOPREVENIMSS 2006.
Table 5 shows wide variations in the prevalence of overweight among regions and age groups. Overweight increases with age. The highest prevalence among children occurred in the Southeast region, while the North region had the highest prevalence for the other age groups. Obesity was more frequent in the South and Southeast regions.
Geographical prevalence of Type 2 diabetes mellitus and hypertension Table 6. The table shows the prevalence among individuals that were diagnosed previously and among those that were found as a result of the survey. For type 2 diabetes, the prevalence increases with age and the highest prevalence was found in the Southeast states. As for hypertension, the prevalence of this condition increases with age and an important proportion of individuals did not know about their condition. The highest prevalence was observed in women and older adults interviewed in the Northern states.
Table 6
Prevalence of Type 2 diabetes mellitus and hypertension among women, men and older adults in each region of the country
Condition/age group
Finding
North
Center
South
Southwest
Mexico City
National
%
%
%
%
%
%
Type 2 diabetes
Women
Previously diagnosed
7.9
6.2
6.5
10.6
7.2
7.4
Finding in survey
1.8
1.8
1.2
1.9
1.1
1.7
Total
9.7
8.0
7.7
12.5
8.3
9.1
Men
Previously diagnosed
6.5
6.4
7.5
10.6
6.9
7.2
Finding in survey
1.1
1.2
2.0
0.7
1.2
1.1
Total
7.5
7.6
9.5
11.3
8.1
8.3
Previously diagnosed
30.7
29.5
25.7
32.1
30.4
30.0
Finding in survey
1.3
1.6
2.5
1.3
1.9
1.6
Total
32.0
31.1
28.2
33.4
32.3
31.6
Hypertension
Women
Previously diagnosed
13.8
11.0
13.0
18.9
9.3
12.5
Finding in survey
13.6
9.1
10.1
8.1
6.9
9.5
Total
27.4
20.1
23.1
27.0
16.2
22.0
Men
Previously diagnosed
7.8
7.7
11.0
11.4
6.3
8.2
Finding in survey
17.5
12.5
11.2
14.6
9.2
13.2
Total
25.3
20.2
22.2
26.0
15.5
21.4
Previously diagnosed
43.1
43.3
34.0
41.6
46.9
43.0
Finding in survey
18.9
16.2
19.7
15.0
7.4
15.4
Total
62.0
59.5
53.7
56.6
54.3
58.4
Source: Encoprevenimss 2006
## Discussion
PREVENIMSS' main goals were to increase coverage of preventive services based on health needs. The main findings of these surveys are the continuous increase of the coverage of preventive actions in the five age groups, and the ascertainment of the magnitude of old and emergent unmet needs among IMSS members, such as the high prevalence of anemia among children aged 0-4 years; the significant proportion of undiagnosed cases of hypertension in women, men and older adults and the proportion of people with overweight and obesity.
The coverage of preventive programs that were operational before the onset of PREVENIMSS was the highest since the first survey: Among children these were: measurement of height and weight, completed schemes of vaccination in children < 5 years old and congenital hypothyroidism detection in newborns. Preventive actions in women were, screening for cervical cancer; for women, men and older adults: type 2 diabetes and hypertension and pneumococcal vaccine for older adults.
Measuring coverage is particularly relevant to evaluate performance of individual programs within health systems and of individual countries regarding major international initiatives, such as the Millennium Development Goals (MDG). Mexico is on track to achieve the MDG-4 (two-thirds reduction between 1990 and 2015 in deaths of children under five years) [ 8] and the coverage of preventive actions that IMSS has achieved with its members is an underlying factor of these results, given the size of the population this institution covers.
A conceptual model has been proposed for assessing interventions to improve preventive services. This model comprises seven intervention components (reminders, feedback, education, financial incentives, regulatory interventions, organizational change and media campaign), four potential targets (patient, provider, organization and community) and key intervention features applicable to most of the intervention components (social influence, marketing, outreach, visual appeal, collaboration and teamwork, theory based, top management support and active learning strategies) [ 17].
We analyzed PREVENIMSS using this framework to identify its strengths and limitations. PREVENIMSS implemented several intervention components: reminders (through the booklets that address preventive activities), education (through educational activities aimed at promoting the use of preventive services); regulatory (through modifying the norms, regulations and criteria to provide preventive care); organizational change (through integrating all scattered preventive programs within a single strategy) and media campaign (through advertisements in radio, newspaper and television). The potential targets were, users, providers and the organization at central, district and local level. No financial incentives were considered as part of the intervention, neither actions promoting community participation were implemented as part of the program.
PREVENIMSS is the outcome of organizational changes that could be considered planned and developmental [ 18]. It was planned because it was deliberate, based on conscious reasoning and actions. It was developmental because it aimed at improving or correcting the processes to provide preventive care. Its design considered the demographic and epidemiological patterns of IMSS members and the IMSS' organizational strengths and weaknesses. This approach allowed defining the organizational changes that would contribute in assuring the implementation and sustainability of the program.
The finding of the high rate of anemia (19%) in children under four years of age, confirms what has been reported in other surveys carried out among the IMSS affiliated population (20.5%) [ 19]; the consequences of iron deficiency in the development of children have been widely described. This finding should be a wake-up call to analyze this situation in detail and to develop sound strategies aimed at tackling this problem. It is worth mentioning that IMSS members belong to the formal sector, which represents a regular income; thus, they are able to purchase food and commodities. It is also possible that certain socio-cultural factors like the dietary habits of children could have a negative influence on the possible impact of iron supplementation. Further studies are needed to address this topic.
Regarding the suffering from chronic conditions, ENCOPREVENIMSS reported that a significant proportion of interviewees were unaware of having either hypertension or diabetes. This suggests that PREVENIMSS must increase its screening activities in order to identify and diagnose cases for timely treatment. The interest in reinforcing preventive care for chronic diseases is due to its consequences for the individual and for the family, but also because these are high cost diseases that increase the burden for health care systems and for the society. Preventive services can contribute to avoid premature deaths and save resources.
The high rates of overweight, obesity, type 2 diabetes, and hypertension among interviewees mirrors what is observed in the actual provision of care; these are the main causes of visits to IMSS primary care facilities and among the chief causes of hospitalization. The growing burden of these conditions already represents a heavy toll for health systems [ 20].
The analysis of the geographical distribution of the prevalence of overweight, obesity, type 2 diabetes and hypertension showed important regional differences that allow making several assumptions. The percentage of individuals that did not know about their condition reflects an unmet need for preventive care. It is reasonable to assume a proportion of individuals without screening in a given year; however, given the magnitude of these conditions, this proportion should not be high. The analysis of the capacity to provide preventive care along with the knowledge about the actual demand and the information at local or regional level are necessary elements to estimate the actual and potential coverage and to set regional relevant goals for screening and to reinforce preventive actions in targeted age groups. Also, the geographical variations would indicate that certain socio-demographic conditions, such as income, access to food and lifestyle might have an important influence.
To interpret the findings of the surveys it is important to consider two main limitations in the design and focus of the evaluation. 1) The non-response rate as a source of bias. To compensate for the non-response rate we carried out two actions: a) To draw a larger sample size than needed (10%) and b) to replace the non-respondent households. However, the decision of replacing the household is a non-sampling error that carries out several potential problems, because the attempts to substitute non-responding households are time-consuming, prone to errors and a source of bias [ 21]. Given that the extent of non-response rate was below 10% in the four surveys, we may assume that this reduces the bias.
This strategy was focused to obtain an efficient sample design. The use of clusters allowed controlling costs and we aimed at maintaining the design effect as low as possible. It is well known that the default value for the design effect should be of 1.5 to 2.0, but this implied a considerable increase in the number of households and in the costs. We used a feasible number of clusters, within each, the smallest cluster size in terms of the number of households and this number was constant. It was also considered the information of previous surveys carried out in Mexico.
2) The surveys were not designed to measure or to evaluate the organizational change at the family medicine clinics. This shortcoming should be addressed in the short term and evaluating the organizational changes will provide key information to improve PREVENIMSS performance.
3) The survey did not collected information about the diphtheria-tetanus vaccine. This vaccine is routinely applied and the IMSS information system reports acceptable coverage figures however we should accept that this information should be included as part of the data.
Prevention is gaining attention in the international arena. In 2005, to address prevention and control of chronic diseases, the World Health Organization published a stepwise framework that comprises three core steps: 1. Estimate population needs and advocate for action, 2. Formulate and adopt policy, 3. Identify policy implementation steps. In a broader sense, IMSS actions that began in 2001 are similar to what WHO advices; PREVENIMSS identifies population needs and addresses the prevention component, while curative services, including primary care and hospital care are in charge of the control component. Theoretically, this is the right way. However, in a complex healthcare system, continuity and coordination of care between preventive and curative care, and among levels of care, requires strong advocacy and profound organizational changes [ 22].
The opportunity cost of preventive programs must be taken into account when designing health policies. Despite the potential benefits of preventive care, the fact is that most of primary care services are focused on providing curative care. Health policies in Mexico are oriented towards increasing coverage of health care and universal access. From our perspective, the focus should be to provide universal access to primary care services, which in turn comprises reinforcement of preventive services and provision of therapeutic care. The rational for this recommendation is straightforward: preventive care aims to avoid or delay the occurrence of diseases, to detect timely a disease, to avoid or delay complications when the condition is already present, to avoid premature deaths and to save resources. In fact, given that preventive care is appropriate for all, its provision is the first step to provide universal coverage, which in turn contributes in improving population health and reduces health disparities.
The rise in chronic diseases and the aging of the population are prompting decision makers and healthcare systems to look for prevention strategies that would help cope with this growing problem [ 23]. The impact of prevention services is not negligible; the financial resources saved can be used to pay for highly complex and more costly medical problems [ 24], yet this is an ongoing research field [ 25]. The resources allocated for preventive activities are far from enough and much more investment is needed. The aim is not to privilege preventive care over curative care, but to find the optimal balance between these forces while looking for cost-effective alternatives.
Analyzing the actual impact of PREVENIMSS on institutional performance is advisable. PREVENIMSS has already increased the demand for preventive care, which is due to both, changes in the organization that facilitated access to preventive services and users' demand as a result of the media campaigns and the information that was given personally when the users received the PREVENIMSS booklets. The increase in screening of diseases such as cancer, hypertension and diabetes will put further pressure on curative services to confirm the diagnosis and to provide timely and appropriate treatment to those already ill. This requires careful planning and reinforcement of current health services infrastructure to fulfill potential demand; currently there is no evidence of the impact of this increase on the actual provision of services.
Evaluating the impact of preventive actions would provide evidence of the cost-benefit of reinforcing prevention. To date there is no conclusive evidence of the benefit of preventive care for specific conditions. The analysis of the U.S. Preventive Service Task Force pointed out the lack of evidence on the health benefits of detecting type 2 diabetes, but it accepts that the benefits can be observable for hypertensives [ 26]. In fact the benefit of individual interventions, for example vaccines, screening of specific diseases or interventions aimed at improving lifestyle should be carefully analyzed from different perspectives. An adequate approach could be to measure effective coverage of preventive actions. Although, the significance as well as the difficulties and limitations in measuring effective coverage in Mexico have been addressed previously [ 27].
## Conclusion
After five years of its implementation, PREVENIMSS showed an important increase in coverage for the principal components of the program, and its working model could be applicable to reinforce nationwide preventive programs. The unsolved problems such as anemia, and the emerging ones such as overweight, obesity, among others, point out the need to strength preventive care through designing and implementing innovative programs aimed to attain effective coverage for those conditions in which prevention obtains substandard results
## Acknowledgements
1. Instituto Mexicano del Seguro Social: Programa de Proyectos Estratégicos de la Coordinación de Investigación en Salud. Proyectos FP 0331/2003/203, 2005--785-067 y 2005-785-176, 2006/1B/I/001.
2. Coordinación de Salud Publica partida 0213 y 1603
3. Programa de Salud Comunitaria. Partidas presupuestales 0213, 0237, 1603, 1605 and 2415.
4. Consejo Nacional de Ciencia y Tecnología. CONACYT Proyecto Sectorial No. 7400
## Competing interests
The authors declare that they have no competing interests.
## Authors' contributions
GG, OM and SL contributed in developing the PREVENIMSS program; GG, HR, BA and SFC developed and conducted the surveys and carried out the statistical analysis of ENCOPREVENIMSS. RPC and HRM conceptualized and wrote the paper. All authors critically edited the manuscript, participated in the interpretation of data and read and approved the final version.
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https://www.physicsforums.com/threads/draw-a-circuit-based-on-the-info-and-find-the-voltage-values.734514/ | # Draw a Circuit based on the info and find the voltage values
1. Jan 23, 2014
### yaro99
1. The problem statement, all variables and given/known data
Consider a circuit containing four nodes
labeled a, b, c, and d. Also, we know that
vab= 12V,vcb=−4V,and vda= 8V. Deter-
mine the values of vac and vcd. (Hint: Draw
a picture showing the nodes and the known
voltages.)
2. Relevant equations
∑ voltages in a loop = 0
3. The attempt at a solution
I had no idea how to approach the problem, just a couple ideas. I tried sketching this out:
This one didn't make much sense to me since applying the loop rule, I get differing answers for $v_{ac}$
So I tried a few other ways to draw it and this was the closest I could get:
This seems like it makes more sense, but I'm not entirely sure. Am I on the right track?
2. Jan 23, 2014
### collinsmark
I recommend the first thing to change is you need to change your voltage symbol to indicate some sort of polarity. They blue squares alone are not sufficient. Either use a symbol with obvious polarity such as a battery symbol, or (and this is just as good too) label the '+' and '-' signs.
What I mean by that is if you look at the 8 V element in the upper left. Imagine, hypothetically, flipping the polarity of that element, making it VAD = 8 V. If you did so, it wouldn't look any different than the way it is now with VDA = 8 V. You need some way of indicating the polarity. You need to know by looking at your picture that if VDA = 8 V, then VAD = -8 V
Secondly, don't draw that stuff in the middle. It's not necessary. Just keep it as a square if you wish (or even three sides of a square), with nothing in the center. Note that VAC = VAB + VBC
3. Jan 24, 2014
### ehild
It is easier to work with potentials. If Vab means the potential of b with respect to a : Vab=Vb-Va=12 V. Write 0 at point a and 12 V at point b. Draw a battery between the nodes to ensure the given potential difference.
Draw the batteries and determine the potential of each node. Calculate the potential differences Vac=Vc-Va and Vcd=Vd-Vc.
You can connect a resistor between two nodes and an other one between the other two nodes, the potential differences would not change.
ehild
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https://skewed.de/tiago/blog/inference-compression | # News and views
## Inferring, explaining, and compressing
Published on Friday, 03 December, 2021
Tags: community detection, description, inference, Bayes, MDL, SBM
(This is a continuation of the previous blog post, and slightly modified version of chapter II in [peixoto_descriptive_2021])
Inferential approaches to community detection (see [peixoto_bayesian_2019] for a detailed introduction) are designed to provide explanations for network data in a principled manner. They are based on the formulation of generative models that include the notion of community structure in the rules of how the edges are placed. More formally, they are based on the definition of a likelihood $$P({\boldsymbol A}|{\boldsymbol b})$$ for the network $${\boldsymbol A}$$ conditioned on a partition $${\boldsymbol b}$$, and the inference is obtained via the posterior distribution, according to Bayes' rule, i.e.
\begin{equation*} P({\boldsymbol b}|{\boldsymbol A}) = \frac{P({\boldsymbol A}|{\boldsymbol b})P({\boldsymbol b})}{P({\boldsymbol A})}, \end{equation*}
where $$P({\boldsymbol b})$$ is the prior probability for a partition $${\boldsymbol b}$$. Overwhelmingly, the models used for this purpose are variations of the stochastic block model (SBM) [holland_stochastic_1983], where in addition to the node partition, it takes the probability of edges being placed between the different groups as an additional set of parameters. A particularly expressive variation is the degree-corrected SBM (DC-SBM) [karrer_stochastic_2011], with a marginal likelihood given by [peixoto_nonparametric_2017]
\begin{equation*} P({\boldsymbol A}|{\boldsymbol b}) = \sum_{\boldsymbol e, \boldsymbol k}P({\boldsymbol A}|{\boldsymbol k},{\boldsymbol e},{\boldsymbol b})P({\boldsymbol k}|{\boldsymbol e},{\boldsymbol b})P({\boldsymbol e}|{\boldsymbol b}), \end{equation*}
where $${\boldsymbol e}=\{e_{rs}\}$$ is a matrix with elements $$e_{rs}$$ specifying how many edges go between groups $$r$$ and $$s$$, and $$\boldsymbol k=\{k_i\}$$ are the degrees of the nodes. Therefore, this model specifies that, conditioned on a partition $${\boldsymbol b}$$, first the edge counts $${\boldsymbol e}$$ are sampled from a prior distribution $$P({\boldsymbol e}|{\boldsymbol b})$$, followed by the degrees from the prior $$P({\boldsymbol k}|{\boldsymbol e},{\boldsymbol b})$$, and finally the network is wired together according to the probability $$P({\boldsymbol A}|{\boldsymbol k},{\boldsymbol e},{\boldsymbol b})$$, which respects the constraints given by $$\boldsymbol k$$, $${\boldsymbol e}$$, and $${\boldsymbol b}$$. See fig:dcsbm (a) for a illustration of this process.
This model formulation includes fully random networks as the special case when we have a single group. Together with the Bayesian approach, the use of this model will inherently favor a more parsimonious account of the data, whenever it does not warrant a more complex description — amounting to a formal implementation of Occam's razor. This is best seen by making a formal connection with information theory, and noticing that we can write the numerator of eq:bayes as
\begin{equation*} P({\boldsymbol A}|{\boldsymbol b})P({\boldsymbol b}) = 2^{-\Sigma({\boldsymbol A},{\boldsymbol b})}, \end{equation*}
where the quantity $$\Sigma({\boldsymbol A},{\boldsymbol b})$$ is known as the description length [grunwald_minimum_2007] of the network. It is computed as [1]:
\begin{equation*} \Sigma({\boldsymbol A},{\boldsymbol b}) = \underset{\mathcal{D}({\boldsymbol A}|{\boldsymbol k},{\boldsymbol e},{\boldsymbol b})}{\underbrace{-\log_2P({\boldsymbol A}|{\boldsymbol k},{\boldsymbol e},{\boldsymbol b})}}\, \underset{\mathcal{M}({\boldsymbol k},{\boldsymbol e},{\boldsymbol b})}{\underbrace{-\log_2P({\boldsymbol k}|{\boldsymbol e},{\boldsymbol b}) - \log_2 P({\boldsymbol e}|{\boldsymbol b}) - \log_2P({\boldsymbol b})}}. \end{equation*}
The second set of terms $$\mathcal{M}({\boldsymbol k},{\boldsymbol e},{\boldsymbol b})$$ in the above equation quantifies the amount of information in bits necessary to encode the parameters of the model [2]. The first term $$\mathcal{D}({\boldsymbol A}|{\boldsymbol k},{\boldsymbol e},{\boldsymbol b})$$ determines how many bits are necessary to encode the network itself, once the model parameters are known. This means that if Bob wants to communicate to Alice the structure of a network $${\boldsymbol A}$$, he first needs to transmit $$\mathcal{M}({\boldsymbol k},{\boldsymbol e},{\boldsymbol b})$$ bits of information to describe the parameters $${\boldsymbol b}$$, $${\boldsymbol e}$$, and $${\boldsymbol k}$$, and then finally transmit the remaining $$\mathcal{D}({\boldsymbol A}|{\boldsymbol k},{\boldsymbol e},{\boldsymbol b})$$ bits to describe the network itself. Then, Alice will be able to understand the message by first decoding the parameters $$({\boldsymbol k},{\boldsymbol e},{\boldsymbol b})$$ from the first part of the message, and using that knowledge to obtain the network $${\boldsymbol A}$$ from the second part, without any errors.
What the above connection shows is that there is a formal equivalence between inferring the communities of a network and compressing it. This happens because finding the most likely partition $${\boldsymbol b}$$ from the posterior $$P({\boldsymbol b}|{\boldsymbol A})$$ is equivalent to minimizing the description length $$\Sigma({\boldsymbol A},{\boldsymbol b})$$ used by Bob to transmit a message to Alice containing the whole network.
Data compression amounts to formal implementation of Occam's razor because it penalizes models that are too complicated: if we want to describe a network using many communities, then the model part of the description length $$\mathcal{M}({\boldsymbol k},{\boldsymbol e},{\boldsymbol b})$$ will be large, and Bob will need many bits to transmit the model parameters to Alice. However, increasing the complexity of the model will also reduce the first term $$\mathcal{D}({\boldsymbol A}|{\boldsymbol k},{\boldsymbol e},{\boldsymbol b})$$, since there are fewer networks that are compatible with the bigger set of constraints, and hence Bob will need a shorter second part of the message to convey the network itself once the parameters are known. Compression (and hence inference), therefore, is a balancing act between model complexity and quality of fit, where an increase in the former is only justified when it results in an even larger increase of the second, such that the total description length is minimized.
The reason why the compression approach avoids overfitting the data is due to a powerful fact from information theory, known as Shannon's source coding theorem [shannon_mathematical_1948], which states that it is impossible to compress data sampled from a distribution $$P(x)$$ using fewer bits per symbol than the entropy of the distribution, $$H=-\sum_xP(x)\log_2P(x)$$. In our context, this means that it is impossible, for example, to compress a fully random network using a SBM with more than one group [3]. This means, for example, that when encountered with an example like in the figure we considered in the previous blog post, inferential methods will detect a single community comprising all nodes in the network, since any further division does not provide any increased compression, or equivalently, no augmented explanatory power. From the inferential point of view, a partition like in the previous figure (b) overfits the data, since it incorporates irrelevant random features — a.k.a. “noise” — into its description.
In fig:inferential (a) is shown an example of the results obtained with an inferential community detection algorithm, for a network sampled from the SBM. As shown in fig:inferential (b), the obtained partitions are still valid when carried over to an independent sample of the model, because the algorithm is capable of separating the general underlying pattern from the random fluctuations. As a consequence of this separability, this kind of algorithm does not find communities in fully random networks, which are composed only of “noise.”
### Role of inferential approaches in community detection
Inferential approaches based on the SBM have an old history, and were introduced for the study of social networks in the early 80's [holland_stochastic_1983]. But despite such an old age, and having appeared repeatedly in the literature over the years (also under different names in other contexts), they entered the mainstream community detection literature rather late, arguably after the influential paper by Karrer and Newman that introduced the DC-SBM [karrer_stochastic_2011] in 2011, at a point where descriptive approaches were already dominating. However, despite the dominance of descriptive methods, the existence of inferential criteria was already long noticeable. In fact, in a well-known attempt to systematically compare the quality of a variety of descriptive community detection methods, the authors of [lancichinetti_benchmark_2008] proposed the now so-called LFR benchmark, offered as a more realistic alternative to the simpler Newman-Girvan benchmark [girvan_community_2002] introduced earlier. Both are in fact generative models, essentially particular cases of the DC-SBM, containing a “ground truth” community label assignment, against which the results of various algorithms are supposed to be compared. Clearly, this is an inferential evaluation criterion, although, historically, virtually all of the methods compared against that benchmark are descriptive in nature [lancichinetti_community_2009] (these studies were conducted mostly before inferential approaches had gained more traction). The use of such a criterion already betrays that the answer to the litmus test considered in the previous post would be “yes,” and therefore descriptive approaches are fundamentally unsuitable for the task. In contrast, methods based on statistical inference are not only more principled, but in fact provably optimal in the inferential scenario, in the sense that all conceivable algorithms can obtain either equal or worse performance, but none can do better [decelle_asymptotic_2011].
The conflation one often finds between descriptive and inferential goals in the literature of community detection likely stems from the fact that while it is easy to define benchmarks in the inferential setting, it is substantially more difficult to do so in a descriptive setting. Given any descriptive method (modularity maximization, Infomap, Markov stability, etc.) it is usually problematic to determine for which network these methods are optimal (or even if one exists), and what would be a canonical output that would be unambiguously correct. In fact, the difficulty with establishing these fundamental references already serve as evidence that the task itself is ill-defined. On the other hand, taking an inferential route forces one to start with the right answer, via a well-specified generative model that articulates what the communities actually mean with respect to the network structure. Based on this precise definition, one then derives the optimal detection method by employing Bayes' rule.
It is also useful to observe that inferential analyses of aspects of the network other than directly its structure might still be only descriptive of the structure itself. A good example of this is the modelling of dynamics that take place on a network, such as a random walk. This is precisely the case of the Infomap method, which models a simulated teleporting random walk on a network in an inferential manner, using for that a division of the network into groups. While this approach can be considered inferential with respect to an artificial dynamics, it is still only descriptive when it comes to the actual network structure (and will suffer the same problems, such a finding communities in fully random networks). Communities found in this way could be useful for particular tasks, such as to identify groups of nodes that would be similarly affected by a diffusion process. This could be used, for example, to prevent or facilitate the diffusion by removing or adding edges between the identified groups. In this setting, the answer to the litmus test would also be “no”, since what is important is how the network “is” (i.e. how a random walk behaves on it), not how it came to be, or if its features are there by chance alone. Once more, the important issue to remember is that the groups identified in this manner cannot be interpreted as having any explanatory power about the network structure itself, and cannot be used reliably to extract inferential conclusions from it. We are firmly in a descriptive, not inferential setting with respect to the network structure.
Another important difference between inferential and descriptive approaches is worth mentioning. Descriptive approaches are tied to very particular contexts, and cannot be directly compared to one another. This has caused great consternation in the literature, since there is a vast number of such methods, and little robust methodology on how to compare them. Indeed, why should we expect that the modules found by optimizing task scheduling should be comparable to those that optimize the description of a dynamics? In contrast, inferential approaches all share the same underlying context: they attempt to explain the network structure; they vary only in how this is done. They are, therefore, amenable to principled model selection procedures, designed to evaluate which is the most appropriate fit for any particular network, even if the models used operate with very different parametrizations. In this situation, the multiplicity of different models available becomes a boon rather than a hindrance, since they all contribute to a bigger toolbox we have at our disposal when trying to understand empirical observations.
Finally, inferential approaches offer additional advantages that make them more suitable as part a scientific pipeline. In particular, they can be naturally extended to accommodate measurement uncertainties [peixoto_reconstructing_2018] — an unavoidable property of empirical data, which descriptive methods almost universally fail to consider. This information can be used not only to propagate the uncertainties to the community assignments [peixoto_revealing_2021] but also to reconstruct the missing or noisy measurements of the network itself [guimera_missing_2009]. Furthermore, inferential approaches can be coupled with even more indirect observations such as time-series on the nodes [hoffmann_community_2020], instead of a direct measurement of the edges of the network, such that the network itself is reconstructed, not only the community structure [peixoto_network_2019]. All these extensions are possible because inferential approaches give us more than just a division of the network into groups; they give us a model estimate of the network, containing insights about its formation mechanism.
### Behind every description there is an implicit generative model
From a purely mathematical perspective, there is actually no formal distinction between descriptive and inferential methods, because every descriptive method can be mapped to an inferential one, according to some implicit model. Therefore, whenever we are attempting to interpret the results of a descriptive community detection method in an inferential way — i.e. make a statement about how the network came to be — we cannot in fact avoid making implicit assumptions about the model generating process that lies behind it. (At first this statement seems to undermine the distinction we have been making between descriptive and inferential methods, but in fact this is not the case, as we will see below.)
It is not difficult to demonstrate that it is possible to formulate any conceivable community detection method as a particular inferential method. Let us consider an arbitrary quality function
\begin{equation*} W({\boldsymbol A}, {\boldsymbol b}) \in \mathbb{R} \end{equation*}
which is used to perform community detection via the optimization
\begin{equation*} {\boldsymbol b}^* = \underset{\boldsymbol b}{\operatorname{argmax}}\; W({\boldsymbol A}, {\boldsymbol b}). \end{equation*}
We can then interpret the quality function $$W({\boldsymbol A}, {\boldsymbol b})$$ as the “Hamiltonian” of a posterior distribution
\begin{equation*} P({\boldsymbol b}|{\boldsymbol A}) = \frac{\mathrm{e}^{\beta W({\boldsymbol A},{\boldsymbol b})}}{Z({\boldsymbol A})}, \end{equation*}
with normalization $$Z({\boldsymbol A})=\sum_{\boldsymbol b}\mathrm{e}^{\beta W({\boldsymbol A},{\boldsymbol b})}$$. By making $$\beta\to\infty$$ we recover the optimization of eq:opt, or we may simply try to find the most likely partition according to the posterior, in which case $$\beta>0$$ remains an arbitrary parameter. Therefore, employing Bayes' rule in the opposite direction, we obtain the following effective generative model:
\begin{equation*} \begin{aligned} P({\boldsymbol A}|{\boldsymbol b}) &= \frac{P({\boldsymbol b}|{\boldsymbol A})P({\boldsymbol A})}{P({\boldsymbol b})},\\ &= \frac{\mathrm{e}^{\beta W({\boldsymbol A},{\boldsymbol b})}}{Z({\boldsymbol A})}\frac{P({\boldsymbol A})}{P({\boldsymbol b})}, \end{aligned} \end{equation*}
where $$P({\boldsymbol A}) = \sum_{\boldsymbol b}P({\boldsymbol A}|{\boldsymbol b})P({\boldsymbol b})$$ is the marginal distribution over networks, and $$P({\boldsymbol b})$$ is the prior distribution for the partition. Due to the normalization of $$P({\boldsymbol A}|{\boldsymbol b})$$ we have the following constraint that needs to be fulfilled:
\begin{equation*} \sum_{\boldsymbol A}\frac{\mathrm{e}^{\beta W({\boldsymbol A},{\boldsymbol b})}}{Z({\boldsymbol A})}P({\boldsymbol A}) = P({\boldsymbol b}). \end{equation*}
Therefore, not all choices of $$P({\boldsymbol A})$$ and $$P({\boldsymbol b})$$ are compatible with the posterior distribution and the exact possibilities will depend on the actual shape of $$W({\boldsymbol A},{\boldsymbol b})$$. However, one choice that is always possible is
\begin{equation*} P({\boldsymbol A}) = \frac{Z({\boldsymbol A})}{\Xi},\qquad P({\boldsymbol b}) = \frac{\Omega({\boldsymbol b})}{\Xi}, \end{equation*}
with $$\Omega({\boldsymbol b})=\sum_{\boldsymbol A}\mathrm{e}^{\beta W({\boldsymbol A},{\boldsymbol b})}$$ and $$\Xi=\sum_{\boldsymbol A,\boldsymbol b}\mathrm{e}^{\beta W({\boldsymbol A},{\boldsymbol b})}$$. Taking this choice leads to the effective generative model
\begin{equation*} P({\boldsymbol A}|{\boldsymbol b}) = \frac{\mathrm{e}^{\beta W({\boldsymbol A},{\boldsymbol b})}}{\Omega({\boldsymbol b})}. \end{equation*}
Therefore, inferentially interpreting a community detection algorithm with a quality function $$W({\boldsymbol A},{\boldsymbol b})$$ is equivalent to assuming the generative model $$P({\boldsymbol A}|{\boldsymbol b})$$ and prior $$P({\boldsymbol b})$$ above. Furthermore, this also means that any arbitrary community detection algorithm implies a description length [4] given (in nats) by
\begin{equation*} \Sigma({\boldsymbol A},{\boldsymbol b}) = -\beta W({\boldsymbol A},{\boldsymbol b}) + \ln\sum_{\boldsymbol A',{\boldsymbol b}'}\mathrm{e}^{\beta W({\boldsymbol A}',{\boldsymbol b}')}. \end{equation*}
What the above shows is that there is no such thing as a “model-free” community detection method, since they are all equivalent to the inference of some generative model. The only difference to a direct inferential method is that in that case the modelling assumptions are made explicitly, inviting rather than preventing scrutiny. Most often, the effective model and prior that are equivalent to an ad hoc community detection method will be difficult to interpret, justify, or even compute.
Furthermore there is no guarantee that the obtained description length of eq:dl_W will yield a competitive or even meaningful compression. In particular, there is no guarantee that this effective inference will not overfit the data. Although we mentioned in the previous section that inference and compression are equivalent, the compression achieved when considering a particular generative model is constrained by the assumptions encoded in its likelihood and prior. If these are poorly chosen, no actual compression might be achieved, for example when comparing to the one obtained with a fully random model. This is precisely what happens with descriptive community detection methods: they overfit because their implicit modelling assumptions do not accommodate the possibility that a network may be fully random, or contain a balanced mixture of structure and randomness.
Since we can always interpret any community detection method as inferential, is it still meaningful to categorize some methods as descriptive? Arguably yes, because directly inferential approaches make their generative models and priors explicit, while for a descriptive method we need to extract them from back-engineering. Explicit modelling allows us to make judicious choices about the model and prior that reflect the kinds of structures we want to detect, relevant scales or lack thereof, and many other aspects that improve their performance in practice, and our understanding of the results. With implicit assumptions we are “flying blind”, relying substantially on serendipity and trial-and-error — not always with great success.
It is not uncommon to find criticisms of inferential methods due to a perceived implausibility of the generative models used — such as the conditional independence of the placement of the edges present in the SBM — although these assumptions are also present, but only implicitly, in other methods, like modularity maximization (see [peixoto_descriptive_2021]).
The above inferential interpretation is not specific to community detection, but is in fact valid for any learning problem. The set of explicit or implicit assumptions that must come with any learning algorithm is called an “inductive bias”. An algorithm is expected to function optimally only if its inductive bias agrees with the actual instances of the problems encountered. It is important to emphasize that no algorithm can be free of an inductive bias, we can only chose which intrinsic assumptions we make about how likely we are to encounter a particular kind of data, not whether we are making an assumption. Therefore, it is particularly problematic when a method does not articulate explicitly what these assumptions are, since even if they are hidden from view, they exist nonetheless, and still need to be scrutinized and justified. This means we should be particularly skeptical of the impossible claim that a learning method is “model free”, since this denomination is more likely to signal an unwillingness to expose the underlying modelling assumptions, which could potentially be revealed as unappealing and fragile when eventually forced to come under scrutiny.
[peixoto_descriptive_2021] (1, 2) Tiago P. Peixoto, “Descriptive vs. inferential community detection: pitfalls, myths and half-truths”, arXiv: 2112.00183
[holland_stochastic_1983] (1, 2) Paul W. Holland, Kathryn Blackmond Laskey, and Samuel Leinhardt, “Stochastic blockmodels: First steps,” Social Networks 5, 109–137 (1983). DOI: 16/0378-8733(83)90021-7
[karrer_stochastic_2011] (1, 2) Brian Karrer and M. E. J. Newman, “Stochastic blockmodels and community structure in networks,” Physical Review E 83, 016107 (2011). DOI: 10.1103/PhysRevE.83.016107
[peixoto_nonparametric_2017] Tiago P. Peixoto, “Nonparametric Bayesian inference of the microcanonical stochastic block model,” Physical Review E 95, 012317 (2017). DOI: 10.1103/PhysRevE.95.012317
[grunwald_minimum_2007] Peter D. Grünwald, The Minimum Description Length Principle (The MIT Press, 2007).
[shannon_mathematical_1948] C. E Shannon, “A mathematical theory of communication”, Bell Syst Tech. J 27, 623 (1948).
[lancichinetti_benchmark_2008] Andrea Lancichinetti, Santo Fortunato, and Filippo Radicchi, “Benchmark graphs for testing community detection algorithms”, Physical Review E 78, 046110 (2008). DOI: 10.1103/PhysRevE.78.046110
[girvan_community_2002] M. Girvan and M. E. J. Newman, “Community structure in social and biological networks,” Proceedings of the National Academy of Sciences 99, 7821–7826 (2002). DOI: 10.1073/pnas.122653799
[lancichinetti_community_2009] Andrea Lancichinetti and Santo Fortunato, “Community detection algorithms: A comparative analysis”, Physical Review E 80, 056117 (2009). DOI: 10.1103/PhysRevE.80.056117
[decelle_asymptotic_2011] Aurelien Decelle, Florent Krzakala, Cristopher Moore, and Lenka Zdeborová, “Asymptotic analysis of the stochastic block model for modular networks and its algorithmic applications”, Physical Review E 84, 066106 (2011). DOI: 10.1103/PhysRevE.84.066106
[peixoto_reconstructing_2018] Tiago P. Peixoto, “Reconstructing Networks with Unknown and Heterogeneous Errors”, Physical Review X 8, 041011 (2018). DOI: 10.1103/PhysRevX.8.041011
[peixoto_revealing_2021] Tiago P. Peixoto, “Revealing Consensus and Dissensus between Network Partitions”, Physical Review X 11, 021003 (2021). DOI: 10.1103/PhysRevX.11.021003
[guimera_missing_2009] Roger Guimerà and Marta Sales-Pardo, ”Missing and spurious interactions and the reconstruction of complex networks“, Proceedings of the National Academy of Sciences 106, 22073–22078 (2009). DOI: 10.1073/pnas.0908366106
[hoffmann_community_2020] Till Hoffmann, Leto Peel, Renaud Lambiotte, and Nick S. Jones, ”Community detection in networks without observing edges“, Science Advances 6, eaav1478 (2020). DOI: 10.1126/sciadv.aav1478
[peixoto_network_2019] Tiago P. Peixoto, ”Network Reconstruction and Community Detection from Dynamics,“ Physical Review Letters 123, 128301 (2019). DOI: 10.1103/PhysRevLett.123.128301
[peixoto_bayesian_2019] Tiago P. Peixoto, ”Bayesian Stochastic Blockmodeling“, in Advances in Network Clustering and Blockmodeling (John Wiley & Sons, Ltd, 2019) pp. 289–332. DOI: 10.1002/9781119483298.ch11
[mackay_information_2003] David J. C. MacKay, ”Information Theory, Inference and Learning Algorithms", first edition ed. (Cambridge University Press, 2003).
[1] Note that the sum in eq:dcsbm-marginal vanishes because only one term is non-zero given a fixed network $${\boldsymbol A}$$.
[2] If a value $$x$$ occurs with probability $$P(x)$$, this means that in order to transmit it in a communication channel we need to answer at least $$-\log_2P(x)$$ yes-or-no questions to decode its value exactly. Therefore we need to answer one yes-or-no question for a value with $$P(x)=1/2$$, zero questions for $$P(x)=1$$, and $$\log_2N$$ questions for uniformly distributed values with $$P(x)=1/N$$. This value is called “information content”, and essentially measures the degree of “surprise” when encountering a value sampled from a distribution. See [mackay_information_2003] for a thorough but accessible introduction to information theory and its relation to inference.
[3] More accurately, this becomes impossible only when the network becomes asymptotically infinite; for finite networks the probability of compression is only vanishingly small.
[4] The description length of eq:dl_W is only valid if there are no further parameters in the quality function $$W({\boldsymbol A},{\boldsymbol b})$$ other than $${\boldsymbol b}$$ that are being optimized. | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 1, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.7743699550628662, "perplexity": 906.8382670558761}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2022-27/segments/1656103329963.19/warc/CC-MAIN-20220627073417-20220627103417-00761.warc.gz"} |
https://stats.stackexchange.com/questions/26016/sample-size-for-logistic-regression | # Sample size for logistic regression?
I want to make a logistic model from my survey data. It is a small survey of four residential colonies in which only 154 respondents were interviewed. My dependent variable is "satisfactory transition to work". I found that, of the 154 respondents, 73 said that they have satisfactorily transitioned to work, while the rest did not. So the dependent variable is binary in nature and I decided to use logistic regression. I have seven independent variables (three continuous and four nominal). One guideline suggest that there should be 10 cases for each predictor / independent variable (Agresti, 2007). Based on this guideline I feel that it is OK to run logistic regression.
Am I right? If not please let me know how to decide the number of independent variables?
• I have never really understood the rule of thumb that says "10 cases for each predictor" (and unfortunately I don't have access to the book written by Agresti). What I mean is: if I have 100 subjects of which 10 are cases (the 1's) and 90 non-cases (the 0's), then the rule says "include only 1 predictor". But what if I model the 0's instead of the 1's and then I take the reciprocal of the estimated odds ratios? Would I be allowed to include 9 predictors? That makes no sense to me. – boscovich Apr 7 '12 at 10:13
• Dear Andrea, I have said the same thing that you mean. Out of 154 respondents there are 73 cases (the 1's and rest 0's). Could you throw some light on my question.Thanks! – Braj-Stat Apr 7 '12 at 15:56
• In a commentary i have read that one has to look at the minimum of the number of events and non-events. So in the example of 10/100 you end up with one predictor irrespective of how you code it. – psj Apr 8 '12 at 11:08
• @psj that sounds reasonable. Do you have any references? – boscovich Apr 12 '12 at 7:30
• There is a related discussion here: minimum-number-of-observations-for-logistic-regression. – gung - Reinstate Monica Dec 13 '12 at 14:20
There are several issues here.
Typically, we want to determine a minimum sample size so as to achieve a minimally acceptable level of statistical power. The sample size required is a function of several factors, primarily the magnitude of the effect you want to be able to differentiate from 0 (or whatever null you are using, but 0 is most common), and the minimum probability of catching that effect you want to have. Working from this perspective, sample size is determined by a power analysis.
Another consideration is the stability of your model (as @cbeleites notes). Basically, as the ratio of parameters estimated to the number of data gets close to 1, your model will become saturated, and will necessarily be overfit (unless there is, in fact, no randomness in the system). The 1 to 10 ratio rule of thumb comes from this perspective. Note that having adequate power will generally cover this concern for you, but not vice versa.
The 1 to 10 rule comes from the linear regression world, however, and it's important to recognize that logistic regression has additional complexities. One issue is that logistic regression works best when the percentages of 1's and 0's is approximately 50% / 50% (as @andrea and @psj discuss in the comments above). Another issue to be concerned with is separation. That is, you don't want to have all of your 1's gathered on one extreme of an independent variable (or some combination of them), and all of the 0's at the other extreme. Although this would seem like a good situation, because it would make perfect prediction easy, it actually makes the parameter estimation process blow up. (@Scortchi has an excellent discussion of how to deal with separation in logistic regression here: How to deal with perfect separation in logistic regression?) With more IV's, this becomes more likely, even if the true magnitudes of the effects are held constant, and especially if your responses are unbalanced. Thus, you can easily need more than 10 data per IV.
One last issue with that rule of thumb, is that it assumes your IV's are orthogonal. This is reasonable for designed experiments, but with observational studies such as yours, your IV's will almost never be roughly orthogonal. There are strategies for dealing with this situation (e.g., combining or dropping IV's, conducting a principal components analysis first, etc.), but if it isn't addressed (which is common), you will need more data.
A reasonable question then, is what should your minimum N be, and/or is your sample size sufficient? To address this, I suggest you use the methods @cbeleites discusses; relying on the 1 to 10 rule will be insufficient.
• Can you provide a reference for the statement "One issue is that logistic regression works best when the percentages of 1's and 0's is approximately 50% / 50%"? I've been wondering about this myself, as I have a dataset that is very far from 50/50 and I'm wondering the implications. (sorry to resurrect the thread) – Trevor Sep 6 '13 at 1:48
• I don't see any problem w/ resurrecting an old thread when it's appropriate, @Trevor. I think what you are looking for is something along the lines of this nice answer by conjugate prior: does-an-unbalanced-sample-matter-when-doing-logistic-regression. – gung - Reinstate Monica Sep 6 '13 at 2:11
• +1 to Trevor's question. I believe that logistic regression will continue to benefit from new data, even if that data is of the same case (despite diminishing returns). That's actually something that has bothered me about machine learning techniques like random forests - that they can get worse by adding more relevant training data. Perhaps there's a point at which logistic regression would break down due to numerical considerations if the imbalance became too severe. Would be interested in learning more about this. – Ben Ogorek Dec 27 '16 at 19:17
• +1, perhaps this is implied by your answer I'm not sure, but I'm wondering how this works for categorical variables with different levels? Would it be suggested to have 10 observations per level? – baxx Apr 17 '19 at 23:41
• It's a rule of thumb, @baxx, but yes, to do more than just estimate the percentages, you would need at least 45. – gung - Reinstate Monica Apr 18 '19 at 1:12
I typically use a 15:1 rule (ratio of min(events, non-events) to number of candidate parameters in the model). More recent work found that for a more rigorous validation 20:1 is needed. More information may be found in my course handouts linked from http://biostat.mc.vanderbilt.edu/rms, in particular an argument for a minimum sample size of 96 just to estimate the intercept. But the sample size requirement is more nuanced, and an even more recent paper addresses this more comprehensively.
Usually, too few cases wrt. the model complexity (number of parameters) means that the models are unstable. So if you want to know whether you sample size / model complexity is OK, check whether you obtain a reasonably stable model.
There are (at least) two different kinds of instability:
1. The model parameters vary a lot with only slight changes in the training data.
2. The predictions (for the same case) of models trained with slight changes in the training data vary a lot.
You can measure 1. by looking how much your model coefficients vary if the training data is slightly perturbed. A suitable bunch of models can be calculated e.g. during bootstrap or (iterated) cross validation procedures.
For some types of models or problems, varying parameters do not imply varying predictions. You can directly check instability 2. by looking at the variation of predictions for the same case (regardless of whether they are correct or not) calculated during out-of-bootstrap or iterated cross validation.
There is no strict rules, but you can include all independent variables so long as the nominal variables dont have too many categories. You need one "beta" for all except one of the class for each nominal variable. So if a nominal variable was say "area of work" and you have 30 areas, then you'd need 29 betas.
One way to overcome this problen it to regularise the betas - or penalise for large coefficients. This helps ensure that you model doesn't overfit the data. L2 and L1 regularisation are popular choices.
Another issue to consider is how representative your sample is. What population do you want to make inference of? do you have all the different types of people in the sample that there is in the population? it will be difficult to make accurate inference if your sample has "holes" (eg no females aged 35-50 in the sample or no high income workers etc)
Here is the actual answer from the MedCalc website user41466 wrote about
Sample size considerations
Sample size calculation for logistic regression is a complex problem, but based on the work of Peduzzi et al. (1996) the following guideline for a minimum number of cases to include in your study can be suggested. Let p be the smallest of the proportions of negative or positive cases in the population and k the number of covariates (the number of independent variables), then the minimum number of cases to include is: N = 10 k / p For example: you have 3 covariates to include in the model and the proportion of positive cases in the population is 0.20 (20%). The minimum number of cases required is N = 10 x 3 / 0.20 = 150 If the resulting number is less than 100 you should increase it to 100 as suggested by Long (1997).
Peduzzi P, Concato J, Kemper E, Holford TR, Feinstein AR (1996) A simulation study of the number of events per variable in logistic regression analysis. Journal of Clinical Epidemiology 49:1373-1379.
• So it is the same 10cases per independent variable (with floor) – seanv507 Mar 16 '16 at 20:08
Results from any logistic model with the number of observations per independent variable ranging from at least five to nine are reliable, especially so if results are statistically significant (Vittinghoff & McCulloch, 2007).
Vittinghoff, E., & McCulloch, C. E. 2007. Relaxing the rule of ten events per variable in logistic and Cox regression. American Journal of Epidemiology, 165(6): 710–718.
• Note that it's not strictly the "number of observations per independent variable" that's in question, it's the number of "events." For a logistic regression, the number of "events" is the number of cases in the least-frequent of the two outcome classes. That will be no greater than 1/2 of the number of total observations, and in some applications a good deal lower than that. – EdM Dec 27 '16 at 19:01 | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.594149112701416, "perplexity": 608.9983772345965}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2020-45/segments/1603107897022.61/warc/CC-MAIN-20201028073614-20201028103614-00065.warc.gz"} |
http://www.dcc.fc.up.pt/dcc/Pubs/TReports/TR01/dcc-2001-1-abs.html | 16 NOVEMBRO / SEXTA FEIRA / 08:10
FCUP PT EN
APRESENTAÇÃO PESSOAS ENSINO INVESTIGAÇÃO BIBLIOTECA NOTÍCIAS CONTACTOS
### Sabine Broda and Luís Damas
DCC-FC & LIACC, Universidade do Porto
R. do Campo Alegre 823, 4150-180 Porto, Portugal
Phone: 351 22 6078830, Fax: 351 22 6003654
E-mail: {sbb,luis}@ncc.up.pt}
Junho 2000
## Abstract
In 1996 Takahashi et al. showed that it is possible to describe the set of normal inhabitants of a given type $\tau$, in the standard simple type system, using an infinitary extension of the concept of context-free grammar, which allows for an infinite number of non-terminal symbols as well as production rules. The set of normal inhabitants of $\tau$ corresponds then to the set of terms generated by this, possibly infinitary, grammar plus all terms obtained from those by $\eta$-reduction. In this paper we show that the set of normal inhabitants of a type $\tau$ can in fact be described using a standard (finite) context-free grammar, and more interestingly that the sets of normal inhabitants of all types with a same structure are described by context-free grammars which share one unique underlying structure. The definition of a common scheme for these grammars, which depends uniquely on the given type structure, is based on an alternative representation for types, introduced in 2000 (BrodaDamas-Wollic-2000), which gives us a better insight on the nature of a type's structure and its relation to the structure of the set of its normal inhabitants.
FCUP 2018 | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8307116031646729, "perplexity": 1083.6091086525043}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2018-47/segments/1542039742981.53/warc/CC-MAIN-20181116070420-20181116092420-00421.warc.gz"} |
http://foolishdoings.blogspot.com/2015/01/ | ## Tuesday, January 27, 2015
After my post yesterday about the mine wars, a friend asked about the Sid Hatfield murder. Sid Hatfield was the Chief of Police in Matewan, WV in 1920. Some mine "detectives" came to town to evict strikers from their company-owned houses, and Hatfield got together a posse, saying he would kill the detectives. There were several confrontations, the last resulting in a shootout that left seven detectives and three townspeople dead, including the mayor, Cab Testerman.
Some said Hatfield boasted about pulling the trigger on the head detective, Albert Felts, while others said they saw him track an injured Felts into the post office and finish him off. Two weeks later, Hatfield married Testerman's widow, leading to speculation that the whole shootout was a pretext to get Testerman killed so Hatfield could have his wife. Hatfield took over Testerman's jewelry store and turned it into a firearm supply shop for union men.
Hatfield was tried, but beat the murder charges by claiming self-defense. He said Felts fired the first shot, at Testerman. Highly unlikely, not because Felts was an especially honorable man, but because he was a professional detective who had no particular reason to shoot a town official.
Soon after, Hatfield was charged with another shooting at Mohawk, for which he was supposed to stand trial in Welch. He had also been accused of blowing up a tipple and rifle-butting the superintendent of the Stone Mountain Coal Company when that company's mines were being struck by the UMWA. This was not all the trouble Hatfield was in, but I want to wrap this up.
When Hatfield went to Welch to stand trial, Everett Lively, a secret agent working for the mine operators, shot him dead on the courthouse steps in front of his new wife, the erstwhile Widow Testerman. Hatfield, who was clearly what we today would refer to as a total dirtbag, became an instant martyr to the UMWA.
Anyway, my friend asked whether Hatfield's family had been killed with him. They were not, but I wondered whether he was thinking of the Jock Yablonski murder in 1969. Yablonski had just been elected president of the UMWA as a "reform" candidate. The former president, Tony Boyle, hand-picked successor to John L. Lewis, hired a hitman using embezzled union funds to kill Yablonski and his wife and daughter. Such a nice group of people.
I wrote yesterday that the mine wars were started by the UMWA on behalf of competing coal companies. They sent organizers, but things quickly spun out of control. After the 1921 "Battle of Blair Mountain," which resulted in a visit from the U.S. Army, including a wing of bombers, the UMWA tried to wash their hands of the situation, but they should have known what they were getting into. (The Army did not actually drop bombs on the union. That was done by planes privately hired by the Sheriff of Logan County.)
The union men tied red bandannas around their necks and called themselves rednecks, although the word already meant exactly what it means now. Are rednecks prone to violence? Not really. The violent crime rate in Mingo County, WV today is lower than the national average. It is 2.07, compared to a national average of 3.8. For comparison, the rate in Chicago is 9.00. But crime seems to come in waves, when there are are rival groups. Rednecks do not shoot each other over shoes or video games; there has to be some kind of group dynamic going on. This was well known when the UMWA went into WV, because the Hatfield-McCoy and other feuds that were mainly an aftermath of the Civil War had just died down. The UMWA going into West Virginia, and playing groups off one another, is like Nike trying to market shoes by getting the Rolling 60's to adopt them as a gang uniform. You don't think personal grudges played a role? Everett Lively and the officers of the UMWA local were childhood friends turned enemies!
Anyway. I wanted to say one last thing about John L. Lewis, the so-called hero of the UMWA. Here is a typical miner's house
and here is John L. Lewis's house
## Monday, January 26, 2015
### Another Book About the Mine Wars
I'm reading a new history of the West Virginia mine wars by historian James Green, called The Devil Is Here in These Hills: West Virginia's Coal Miners and Their Battle for Freedom. The story, though told many times, is still exciting.
From the front page of the New York Times, August 2, 1921
Prof. Green says he is an "activist scholar," and his career has been one of advocacy for collectivism. It is no surprise, then, that the book paints the union organizers, who were generally associated with the United Mine Workers of America, as heroic defenders of the working man. As for myself, I am no historian, just the descendant of "company men" who were caught in the middle of the so-called mine wars. When UMWA members were stockpiling guns and ammunition, blowing up tipples and killing company officials in 1921, my grandfather was working miles from home, because the mines back near his home in Ottawa, Boone County, were shut down by strikes. Later that year he was called back to Ottawa to help with an armed defense of the mines and to stop the miners' army from getting through to Logan County to continue wreaking havoc. So you can expect that I have a somewhat different take.
Apparently, public TV has bought the rights to this book and plans to make an American Experience episode out of it. You probably also know about the movie Matewan. A thousand times more people will read the book and see the TV show than read this blog, but still, one must try. It's not my contention that unions are always wrong and companies are always right. In fact, I would never have been born were it not for the UMWA hospital at Welch, West Virginia. But I will make the case that the mine wars were a tragic waste of lives and property that had little to do with workers' rights per se.
Like Green's book, most histories of these events uncritically support the union men. The only really objective one I know of is Bloodletting in Appalachia by Howard Lee. Nearly all the others see the conflict as a moralistic good-versus-evil battle pitting a grassroots movement of saintly miners against oppressive mine operators straight out of a Dickens novel. These kinds of fairy tales are not only condescending, they are by now boring.
You have to realize what a strike meant in the early 1900s. Today, a strike means a picket line. Back then, a strike meant shutting down an operation by beating or killing people on their way to work and by destroying equipment. It is easy to criticize the mine operators for hiring private armies to break strikes if you have the modern kind of strike in mind, instead of what strikes were really like in those days.
By 1912, both the mine operators and the union were using tactics that have no place in decent society. The operators were running company towns like lords over a medieval manor, firing and blacklisting any miners who spoke or acted in ways that displeased management. For their part, the union was using guns and dynamite to shut down nonunion mines.
The natural question is, who started it? Who set off the chain of events that spun out of control until the Army had to be called in?
Contrary to Green's telling, the mine wars were anything but grassroots in origin and anything but ignited by oppression. In 1898, a coal cartel called the "Central Competitive Field" was formed, covering Ohio, Indiana, Illinois and western Pennsylvania. It sought to preserve profits by limiting production, exactly like an OPEC for coal, preventing price competition that would have reduced the cost of coal to consumers. Ultimately, the CCF was willing to pay whatever wage the UMWA demanded and just pass it all onto the consumer. The trouble is, the plan could only work if it were extended over the whole industry, otherwise other mines could undercut the cartel. In exchange for high wages, the UMWA promised the CCF it would unionize West Virginia, which would stop mines there from selling cheap coal. Green claims this is a "conspiracy theory," but alas it was a real conspiracy, not just a theory. Here is a high official of the UMWA, complaining to Congress in 1921 that the CCF operators were not helping them carry out this very promise:
Let me point to the fact that the United Mine Workers of America have diligently and aggressively attempted to carry out the promise made in Chicago in 1898 that they have done everything in their power to redeem any promise they may have made to organize West Virginia. Since 1898 our organization has at various times spent hundreds of thousands of dollars trying to unionize West Virginia. We have also sacrificed human life in the attempt to redeem that promise. In view of the fact that we have spent hundreds of thousands of dollars and that our organizers, our members who have gone there as missionaries in an attempt to redeem that promise have sacrificed their lives and their liberties, we should be given credit for what we have done. I want to ask the operators how much money they have spent and what they have done to aid us to organize West Virginia?
I can guess that the CCF would respond by saying that it was ultimately their mines that were the source of every one of the hundreds of thousands of dollars mentioned above. In effect, the CCF gave the workers a raise, a good portion of which went to the UMWA's strike fund, which had a double function as a sabotage operation against the CCF's competitors. The CCF agreement is a much more convincing explanation of when and why the mine wars happened in West Virginia than any spontaneous uprising of oppressed miners.
It is worse than that. Not only were the "mine wars" sponsored by the CCF, they actually achieved nothing but to rain death and destruction on operators and miners alike. There is no definitive tally of deaths, but in reading these histories, there are one or two killed here, and ten killed there, and a powerhouse blown up here, and children starving in strike colonies there, so it adds up to a lot of suffering.
In the end, the strikes and violence did nothing to unionize southern West Virginia. It was unionized (in 1933) by the federal government, when Roosevelt's NIRA was passed. And once again, the welfare of the workers was incidental to the real goal. The NIRA was drafted by another cartel, this one covering much of American manufacturing. Even liberals came to recognize that the NIRA was crony capitalism at its worst. Most of it was found unconstitutional in 1935, but the labor provisions were retained by subsequent legislation.
The role of the UMWA and its leader, John L. Lewis, is outlined here:
Northern coal-operator associations joined John L. Lewis...in helping to draft Section 7(a) of the NIRA. Because most northern mines had been unionized long before 1933 and could not be deunionized, their owners had long sought the unionization of Appalachia's mines as the ultimate solution to Appalachia's low coal prices...Lewis accepted what amounted to price fixing under the NIRA...in exchange for labor leaders' treasured Section 7(a) of the legislation. Lewis reportedly said at this time that he was only looking out for current miners. Miners' sons, he reportedly said, would have to look for work in the cities. Lewis was manifestly not, however, looking out for all current miners, His initial proposal for a nationwide daily minimum wage of five dollars for all coal miners would have ruined many Appalachian operations, throwing their miners out of work.
Let's think about this. In the depths of the Depression, with people breaking up furniture and burning it in their fireplaces to keep warm, the main concern of the federal government is...that there is too much cheap coal being mined in Appalachia. That is some kind of crazy.
The UMWA, like all unions, promoted the idea that workers have a claim on profits which only the union can help them get. But the CCF and NIRA episodes show that the miners' gains didn't come out of existing profits, they came out of coal prices paid by the public that were inflated by monopolies set up with the connivance of the UMWA. It sort of undermines the whole union narrative.
The UMWA and its allies in the press tried to drum up support for the union by depicting the desperate conditions that existed at times in the mining camps as luridly as possible. It is true that life was desperate at times in the West Virginia mining camps. But whose fault was that? The papers complained that families were living in tent colonies with little to eat. But they failed to point out that those same families had been living in houses with a regular wage until the UMWA induced them to strike. And the very worst times in the coalfields happened in the late 1930s, after unionization.
The saddest chapter is that the UMWA sold out the miners partially after the 1921 battle and completely in 1951 when John L. Lewis accepted the mechanization of the mines in exchange for higher wages for existing miners. It fulfilled his threat that miners' sons would have to look for work in the cities. Mechanization was of course inevitable, and beneficial to the consumers of coal, but that argument would not have garnered any support from the miners, had they been asked.
Green acknowledges this repeated betrayal by the UMWA, which started the whole mess back in 1898, but ends the book by describing a utopian scene of union solidarity in which West Virginia miners enjoy safe working conditions, job security, and sunny days forever. In fact, that lasted about ten years, because the UMWA was bleeding the mines dry. Green says he went to West Virginia recently to see Blair Mountain, where the UMWA battled the coal operators and the police. Do you know what he didn't see? Any of my grandfather's seven kids or their descendants, because they had to disperse from West Virginia to five different states in order to make a living.
Somebody will say that West Virginia's problems were due to the decline of the coal industry, which the union couldn't control. Not so. Even with recent moves to restrict coal-burning power plants, more bituminous coal is being mined now than before unionization, but the industry supports only a small fraction of the families it used to. The UMWA didn't stop the process or even try to slow it down. So what did the violence achieve? Do we really need to hold up this blood-soaked history as something to be proud of, or as an inspiration to today's workers? Blair Mountain should be protected from mountaintop removal and preserved in the interest of history, but as caution, not inspiration.
## Saturday, January 17, 2015
### Math Extra #3: Functions
Ten months ago I posted Math Extras #1 and 2 which I wrote for my son. At long last, here is Math Extra #3. This is for kids taking algebra. By the way, I solved the problem of how to typeset math in Blogger by using MathJax. It isn't perfect, but it's a whole lot better than the alternatives.
## Functions
In the later stages of algebra, and on into calculus, we start to study functions a lot. A function is just a rule for generating a value from an input. The input is called an argument. Usually, the function is an algebraic expression, like $x^2-10$. For an input or argument of $x=1$, the value is $1^2-10$, which is $-9$. Sometimes we want to refer to functions by name instead of explicitly. First I'll talk about why we would want to do this. Then I'll give some examples and problems.
The following shows the difference between writing a function explicitly and referring it to by name:
Explicitly: The function $y=x^2+x-6$ has the value zero for $x=2$ and $x=-3$."
By name
• First we give the function a name: $f(x) \equiv x^2+x-6$
• Then we can refer to it by name: $f(x)=0$ for $x=2$ and $x=-3$."
The explicit statement of the function above uses the dependent variable $y$. Don't confuse the name of the function with the dependent variable. We can use any dependent variable we want; for example, we could write $y=f(x)$, meaning $y=x^2+x-6$, or we could write $z=f(x)$, meaning $z=x^2+x-6$. You say $f(x)$ like this: f of x."
Naming a function makes it easy to talk about different arguments. We can write $f(5)$ when we mean $5^2+5-6$. We can also write $f(x+2)$ when we mean $(x+2)^2+(x+2)-6$. Eventually, you will study functions that have more than one argument, such as $f(x,y,z)$. You would say this as, f of x, y and z."
Did you notice that when I named the function, I used the symbol $\equiv$ instead of $=$? The three lines are on purpose. They indicate that this is a definition, just giving something a name. That's a completely different idea than stating two things are equal to each other. Not everyone is careful about this. They might give the definition as $f(x)= x^2+x-6$. But I think you can see that $f(x)=2$ is an equation, and doesn't have anything to do with the definition $f(x)\equiv x^2+x-6$. An explicit way to write that equation is $x^2+x-6=2$.
This naming may seem like too much trouble, but functions can become very lengthy and we may want to refer to them again and again. For example,
The gamma function is defined as $\Gamma(t)\equiv\int_0^\infty x^{t-1} \text{e}^{-x} \, \text{d}x.$ It satisfies the identity $\Gamma(t+1)=t\Gamma(t)$. It is closely related to the factorial, because for integer arguments, $\Gamma(n)=(n-1)!$"
It's not important to understand what the preceding sentence means, just to appreciate that it would have been a lot longer and more confusing if we had to refer to the gamma function explicitly instead of as just $\Gamma(t)$.
Giving a function a name enables abstraction, which is what math is all about. By abstraction, I mean talking about the general properties of something instead of just specific examples. You already know that a variable can be used to represent a number, as in $x=5$. And you also know that we can make statements such as $x+y=y+x$. That equation expresses the commutative property of addition. It's true no matter what the specific values of $x$ and $y$ are. If you think about it, this simple statement contains a tremendous, in fact infinite, amount of information. To write it without using variables, you would have to write
\begin{align}
1 + 2 &= 2 + 1 \\
1 + 3 &= 3 + 1 \\
1 + 4 &= 4 + 1 \ldots
\end{align}
and so on, covering all possible sums of two numbers. Without using variables, it would literally require an infinite number of specific examples to completely define the commutative property of addition.
Using named functions enables a similar kind of abstraction. For example, a fact about functions from calculus is
\frac{\text{d}}{\text{d}t}f(x(t))=\frac{\text{d}}{\text{d}x}f(x)\frac{\text{d}}{\text{d}t}x(t)
This is true no matter what the functions $f$ and $x$ are. For now, you don't need to know what all the d's are doing, but you can see that this would be impossible to write without being able to refer to functions by name instead of explicitly. This example also shows that the argument of a function can be a function itself.
Examples
Let $f(x)\equiv x^2+2x-3$. If $x=0$, then $f(x)=-3$. Another way to write this is $f(0)=-3$. On the other hand, $f(-1)=-4$. The values of $x$ for which $f(x)=0$ are called the zeros or roots of $f(x)$. Note that these are not $f(0)$. They are the solutions of the equation $f(x)=0$. The roots of this $f(x)$ are $x=1$ and $x=-3$. Not every function has roots.
A function that has the same value for both signs of an argument is called an even function. $g(x)=x^2$ is an example of an even function. Its value is 4 for both $x=2$ and $x=-2$. If a function has the same value except with the sign flipped, it is called an odd function. $h(x)=x^3$ has the value $h=27$ for $x=3$ and $h=-27$ for $x=-3$. Therefore, it is an odd function. The function $f(x)$ as defined above is neither even nor odd.
It's important to understand the difference between the value of a function and the function itself. Let $f_1(x)\equiv 4x-4$ and $f_2(x)\equiv 3x-3$. It is true that $f_1(1)=f_2(1)=0$. However, $f_1(x)\neq f_2(x)$ otherwise. They are two different functions.
Sometimes we can draw conclusions about a function even if we don't know exactly what it is. Forget" the definition of $f(x)$ we stated above, so that we can re-use the name $f$. Now, if $f(x)=3f(2x)$, and $f(6)=-5$, then $f(3)=-15$. How do we know this? Let $x=3$ and evaluate $f(x)$ and $f(2x)$. In this paragraph, we have discarded the old definition of $f(x)$. You have to be careful to understand when a function has been redefined. Math books or exams will typically be very careful about this. When they talk about $f(x)$ in a single problem or explanation, they usually mean the same definition of $f(x)$. Science books might not be so careful about it. When they say If $f(x)=\ldots$", they probably only intend that definition of $f(x)$ to hold in that particular statement.
The name we give to the argument doesn't matter in some situations. If $x$ and $z$ are two unknown numbers, then writing $f(x)$ is pretty much the same as writing $f(z)$ unless we know something about $x$ and $z$. The only thing to be careful of is not to use the same name for the argument as for the value of the function, unless you really mean it. If you write $y=f(x)$, there is a value of $y$ corresponding to each possible value of $x$. But if you write $x=f(x)$, you've written an equation that may be solvable for $x$. For example, if $f(x)\equiv 5x-3$, then the equation $x=f(x)$ has one solution, $x=3/4$.
Because the important thing is the form of the function, and not the names of the variables, sometimes people write functions as $f(\bullet)$. That means any name could be used for the argument. This is because, for example, $f(x)\equiv 4x^2-x+1$ and $f(z)\equiv 4z^2-z+1$ are really the same function. Everything that is true of $f(x)$ is also true of $f(z)$, as long as there is nothing special about $x$ and $z$.
When the argument of a function is itself a function, the overall function is called the composition of two functions. It can just be written as $f(g(x))$, or it can be written more formally as $f \circ g$. For example, if $f(x)\equiv 2x-1$ and $g(x)\equiv -x+8$, then $f(g(x))=2(-x+8)-1=-2x+15.$
When a function is raised to a power, say the power of 2, it's written $f^2(x)$, not $f(x)^2$. Note that $f^2(x)$ is not the same thing as $f(x^2)$.
Problems
1. If $f(x)\equiv x+3$ and $g(x)\equiv 2x-3$, for what value or values of $x$ does $f(x)=g(x)$?
2. Is $g(x)\equiv x^4+x^2+3$ even, odd or neither?
3. What are the roots of $f(x)\equiv x^2-36$?
4. Suppose $f(x)$ is odd and $g(x)=3f(x)$. If $f(2)=-4$, then what is $g(-2)$?
5. If $\phi(y)\equiv 3y$, what is $\phi^3(z)$?
6. If $f(x)\equiv 4x+9$ and $g(x)\equiv x^2+3x+7$, what is $f \circ g$ for $x=0$?
7. If $f(x)$ and $g(x)$ are both even, and $f(5)=1$ and $g(-1)=5$, then what is $f \circ g$ if $x=1$?
8. Is composition of functions commutative? Hint: Let $g(x)\equiv -x$ and $f(x)\equiv x^2$. What is $f \circ g$? What is $g \circ f$? If you have trouble keeping track of the signs, substitute in a specific value like $x=1$.
Extra Info
You have probably seen things like $\sin(x)$ and $\log(x)$ on your calculator or elsewhere. These are named functions. They have fixed definitions (not given here) that everyone in math accepts. Whenever anyone writes $\sin(x)$, everyone knows it is the sine function from trigonometry. So don't choose names for your functions that are the same as the standard ones. But aside from the fact that these are standard functions, they work just like the functions you name yourself.
One thing about the standard functions is that their names are always typeset in Roman font, whereas the variables are always written in italics. This helps people not get confused into thinking that $\sin(x)$ means $s$ times $i$ times $n$ times $x$. One can argue that functions we name ourselves should also be in Roman font: $\text{f}(x)$ instead of $f(x)$. But nobody ever does this.
Usually, people omit the parentheses from standard functions. They write $\sin x$ instead of $\sin(x)$. They only use the parentheses in cases where there could be some confusion, such as $\tan (3x+6)$. That clarifies that the argument is $3x+6$. If you wrote $\tan 3x+6$ someone might think you meant $\tan(3x)+6$. But you never write $f x$. It always has to be $f(x)$ or else people will think you mean $f$ times $x$.
When picking names for functions, people usually start with $f$ (for function"), then go to $g$ and $h$. After that, practices vary. If you run out of Roman letters, you can use Greek letters like $\Gamma$ (capital gamma), or Gothic letters like $\mathfrak{F}$ or whatever. Avoid using calligraphic letters like $\mathcal{F}$, script letters like $\mathscr{F}$ or bold letters like $\mathbb{F}$. Those are usually used for other kinds of mathematical objects.
Other ways to write the definition of a function are $f(x) \triangleq 2x-7$ and $f(x)$ ${\scriptsize{\text{def}}}\atop{=}$ $2x-7$. A really formal way to do it is
f(x): x \rightarrow 2x-7.
This formal way is called a mapping". It means that the function $f(x)$ maps" any argument $x$ to a different number $2x-7$.
In the beginning, I said that a function is usually an algebraic expression, but doesn't have to be. It could just as well be defined by a table, like this:
$x$ $f(x)$
$-2$ $2$
$-1$ $0$
$0$ $-2$
$1$ $-4$
$2$ $-6$
The function defined by this table is only defined for the specific arguments listed; that is, the integers between $-2$ and 2. $f(10)$ has no meaning, and neither does $f(0.5)$.
A function can also be defined in words, like this: For any real number $x$, let $f(x)$ be the next biggest integer." For example, $f(4.66)=5$. You can then use $f(x)$ in discussions.
Some algebra books say that a function can have only one value for any given argument, or else it technically isn't a function. For example, if $f(x) \equiv \sqrt{x}$, then for $x=9$, $f(x)=3$ and $-3$. They would say $\sqrt{x}$ is an expression, but not a function. This is a matter of words, not mathematics. Almost every book after algebra doesn't bother with this kind of hairsplitting. You might say that $f(x)$ is multi-valued, but you'd still call it a function. If you want to get technical, you can say that $f(x)=\sqrt{x}$ is not a one-to-one mapping.
## Saturday, January 10, 2015
### Separated at Birth
Mr. Van Driessen from Beavis and Butt-head
Teacher from a brochure recently sent to my son
## Friday, January 9, 2015
### The Dope Filter
Mario Cuomo died this week, so he was in the news. Something that caught my eye was the following thing he said: "You're telling me that the Mafia is an organization, and I'm telling you that's a lot of baloney."
Now, Mario Cuomo was obviously a very able and intelligent person, so I can't imagine he really believed that. But was he lying? For normal people the answer would be yes. For politicians, though, the answer is more complicated.
I believe Cuomo was employing what you might call the "dope filter". Good politicians know how to use it. The dope filter is what you pass your real beliefs through before stating them for public consumption. Cuomo certainly knew that the Mafia is a real organization, but that most Italians are law-abiding. But he also knew that many voters can't understand that both of those statements can be true at the same time. For them, it's one or the other.
Given the limited ability of many people to deal with subtlety, Cuomo chose the path of least harm. He said the Mafia wasn't an organization not because it was true, but to preserve the fact that most Italians are law-abiding.
Most average people don't really care enough about the Mafia to get upset if some politician pretends it doesn't exist. The ones who do can be divided into two groups: Italians and "law-and-order" types. There is of course some overlap between the two groups, but only the "law-and-order" types would take issue with what Cuomo said. And when they did, he could easily deflect it by constructing some weird definition of an organization that the Mafia doesn't meet, or say that he really meant they have five organizations in New York and others in other cities, and they aren't all masterminded by one guy, so therefore it isn't "an organization", or other weaselings.
Don't get the idea that I am looking down on dopey voters. (Well, I am a little.) If you ask me why the Columbia burned up, I'm just going to say the heat shield was damaged by a piece of ice. I'm not going to get into the fact that this had happened many times previously, so the real cause was a flawed means of assessing the damage, blah blah blah, because it's just going to obscure the basic facts.
Sometimes I worry that people are using the "dope filter" on me. I'm a very literal person, so I don't catch on to body language and tone of voice as well as other people. I can imagine that people have to adopt a special, unusually direct way of talking when they talk to me, for fear of not communicating. They have to turn down the bandwidth a little, so there are things they can't communicate to me that they might be able to communicate to others.
## Monday, January 5, 2015
### We Who Write Bad Books
I read some interesting quotes by George Kennan, the diplomat and historian, so on impulse I bought his diary and a short book he wrote called Around the Cragged Peak, which was sort of a grab bag of his personal musings on politics, foreign relations, culture and whatnot. I figured anything he wrote would be worth reading, because he lived so long (101 years) and was involved in so many momentous events of the Cold War, an era I've always taken an interest in.
Well, I figured wrong. The diary was so whiny that I wished I hadn't ordered the book, but it was already done. I understand that a lot of diaries are whiny, but you shouldn't publish the ones that are. One thing I did learn was why the military has always been uncomfortable with the State Department. Guys like Kennan, Dulles (both of them) and James Jesus Angleton were so literate and glib that they could say one thing and then convince you they'd meant the exact opposite and that it was your fault for misunderstanding.
The book was better than the diary, but man, was it long-winded. He takes about four pages to say that nationalism is good as long as you don't take it too far. You know how Strunk and White say to omit needless words, like "at this juncture it is perhaps not inappropriate to point out that"? He must have skipped that chapter. I've come to dislike that sort of excessively precise writing, like "He had had a serious operation" instead of just "He had a serious operation". If you need to support your ideas with so many props and ornaments, maybe you had better consider whether they are good ideas. I think I mostly agreed with Kennan's politics. I think.
Come to that, I've lost interest in the "magnum opus". I used to think it would be cool to write a magnum opus; you know, put down on paper the sum total of your views on some topic of importance. But why? The theme of a magnum opus isn't the ideas, it's the author. And let's face it, most of us aren't that interesting, except to people who know us personally. If you want to write a magnum opus, you should give it away free to your friends and family, not charge a stranger money for it.
The technical equivalent of the magnum opus is the textbook or handbook. When I see a textbook with a grandiose title like Fracture: An Advanced Treatise, I just want to run in the other direction. Geezus, a treatise? The worst one is The Structure of Evolutionary Theory by Gould. The fact that he didn't just call it Evolution should be a warning to you.
I got drafted into writing a chapter of one of these magisterial handbooks about five years ago. The trouble with handbooks is that they usually can't get the best people to contribute, because the best people are too busy to write handbook chapters. I happened to be in a slow spot in my career where I had some free time and was looking for something to do, so I finished my chapter right away, and the editors used it to get the whole project greenlighted for publication. You can guess that all the big shots who were supposed to write the other chapters took a lot longer, and in fact the book is still not done. At this rate, the material will be obsolete before it ever hits the presses. If you think you need a handbook, my advice is to find a good review article written by a bona fide expert.
## Saturday, January 3, 2015
### I Stole A Bike
Once upon a time, I stole a bike. Sort of.
It was a weekend morning in the spring of 1990 and I was walking from my apartment on East Norwich Avenue in Columbus to the Ohio State football ticket office, which I believe was in French Field House at the time. Spring is when you buy your discounted student football ticket at Ohio State, and in those days, you had to do it in person. I was almost there, around some bike racks near some dormitories, in the area now occupied by the College of Business.
That's when I saw it - a bike I had to have. It wasn't even locked to the rack, and it was so early there was hardly anyone around. You certainly didn't have to worry about security cameras in those days. So I hopped on the bike and took off. I had it back at my apartment in just a few minutes. Then I walked back to the ticket office and bought my ticket. I figured it was a little too soon to be riding around that same area on the bike.
You know there's going to be more to the story. The reason I had to have that particular bike was that it was in fact my bike. Or, it had been my bike, depending on your point of view. It was a beat-up 10-speed I'd had since high school and had brought down to campus the previous spring. I'd stored it, chained and locked, on the bike rack in front of Taylor Tower where I lived.
During the two- or three-week break between spring quarter and summer quarter, I'd left the bike on the rack in front of Taylor, but when I'd come back to campus for summer classes, it was gone. I had heard there was a campus rule against leaving bikes on the racks during breaks, so maybe the campus police cut the chain and took it away. But it's not like there was a sign to that effect. It's also possible that someone just stole it. At that time all over campus you'd see front wheels chained to racks but with the rest of the bike stolen, because people had run the chain only through the wheel and not the frame of the bike. Or, at the kind of rack where you set the front wheel into a big slot, some idiot would lean on the bike until the wheel bent, so there were these old, rusty bent front wheels all over the place.
I also seem to remember that the campus police would sell bikes they'd confiscated for not having a sticker or whatever, so maybe someone had paid the police for my bike. But I might be remembering incorrectly about that.
Anyway, someone had my bike for almost a whole year. The day I was going to the ticket office, I spotted the bike and knew it was mine, not just someone's similar bike, because there was a rip in the seat that I'd fixed with some of that sneaker repair goo that comes in a tube. It was definitely mine. I had the bike all that summer, but not long after, it got stolen again, this time for good. I didn't have another bike until spring of the next year, when my girlfriend (wife-to-be) bought me a nice mountain bike for my birthday. Wisely, I chained the bike frame itself, not the wheel, to the rack outside my apartment, but they just stole the wheel. Eventually someone came with a bolt cutter and took the rest of the bike, too. It is as if people considered bikes to be communal property.
So, overall I left Ohio State down two bikes. But it felt good getting the first bike back for a while. It halfway felt like stealing, so it was kind of exciting when I took off on it, but how can you steal your own bike? Just because I hadn't seen it in a year didn't make it any less my bike, did it? Who the hell knows. | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.5106019973754883, "perplexity": 1098.2382388045737}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2018-30/segments/1531676588961.14/warc/CC-MAIN-20180715183800-20180715203800-00174.warc.gz"} |
https://xianblog.wordpress.com/tag/barkers-algorithm/ | ## Monte Carlo calculations of the radial distribution functions for a proton-electron plasma
Posted in Books, pictures, Statistics, University life with tags , , , , , , , , on October 11, 2017 by xi'an
“In conclusion, the Monte Carlo method of calculating radial distribution functions in a plasma is a feasible approach if significant computing time is available (…) The results indicate that at least 10000 iterations must be completed before the system can be considered near to its equilibrium state, and for a badly chosen starting configuration, the run would need to be considerably longer (…) for more conclusive results a longer run is needed so that the energy of the system can settle into an equilibrium pattern and steady-state radial distribution functions can be obtained.” A.A. Barker
Looking for the history behind Barker’s formula the other day made me look for the original 1965 paper. Which got published in the Australian Journal of Physics at the beginning of Barker’s PhD at the University of Adelaide.
As shown in the above screenshot, the basis of Barker’s algorithm is indeed Barker’s acceptance probability, albeit written in a somewhat confusing way since the current value of the chain is kept if a Uniform variate is smaller than what is actually the rejection probability. No mistake there! And more interestingly, Barker refers to Wood and Parker (1957) for the “complete and rigorous theory” behind the method. (Both Wood and Parker being affiliated with Los Alamos Scientific Laboratory, while Barker acknowledges support from both the Australian Institute of Nuclear Science and Engineering and the Weapons Research Establishment, Salisbury… This were times when nuclear weapon research was driving MCMC. Hopefully we will not come back to such times. Or, on the pessimistic side, we will not have time to come back to such times!)
As in Metropolis et al. (1953), the analysis is made on a discretised (finite) space, building the Markov transition matrix, stating the detailed balance equation (called microscopic reversibility). Interestingly, while Barker acknowledges that there are other ways of assigning the transition probability, his is the “most rapid” in terms of mixing. And equally interestingly, he discusses the scale of the random walk in the [not-yet-called] Metropolis-within-Gibbs move as major, targetting 0.5 as the right acceptance rate, and suggesting to adapt this scale on the go. There is also a side issue that is apparently not processed with all due rigour, namely the fact that the particles in the system cannot get arbitrarily close from one another. It is unclear how a proposal falling below this distance is processed by Barker’s algorithm. When implemented on 32 particles, this algorithm took five hours to execute 6100 iterations. With a plot of the target energy function that does not shout convergence, far from it! As acknowledged by Barker himself (p.131).
The above quote is from the conclusion and its acceptance of the need for increased computing times comes as a sharp contrast with this week when one of our papers was rejected based on this very feature..!
## Barker at the Bernoulli factory
Posted in Books, Statistics with tags , , , , , , , on October 5, 2017 by xi'an
Yesterday, Flavio Gonçalves, Krzysztof Latuszýnski, and Gareth Roberts (Warwick) arXived a paper on Barker’s algorithm for Bayesian inference with intractable likelihoods.
“…roughly speaking Barker’s method is at worst half as good as Metropolis-Hastings.”
Barker’s acceptance probability (1965) is a smooth if less efficient version of Metropolis-Hastings. (Barker wrote his thesis in Adelaide, in the Mathematical Physics department. Most likely, he never interacted with Ronald Fisher, who died there in 1962) This smoothness is exploited by devising a Bernoulli factory consisting in a 2-coin algorithm that manages to simulate the Bernoulli variable associated with the Barker probability, from a coin that can simulate Bernoulli’s with probabilities proportional to [bounded] π(θ). For instance, using a bounded unbiased estimator of the target. And another coin that simulates another Bernoulli on a remainder term. Assuming the bound on the estimate of π(θ) is known [or part of the remainder term]. This is a neat result in that it expands the range of pseudo-marginal methods (and resuscitates Barker’s formula from oblivion!). The paper includes an illustration in the case of the far-from-toyish Wright-Fisher diffusion. [Making Fisher and Barker meeting, in the end!]
## understanding the Hastings algorithm
Posted in Books, Statistics with tags , , , , , on August 26, 2014 by xi'an
David Minh and Paul Minh [who wrote a 2001 Applied Probability Models] have recently arXived a paper on “understanding the Hastings algorithm”. They revert to the form of the acceptance probability suggested by Hastings (1970):
$\rho(x,y) = s(x,y) \left(1+\dfrac{\pi(x) q(y|x)}{\pi(y) q(x|y)}\right)^{-1}$
where s(x,y) is a symmetric function keeping the above between 0 and 1, and q is the proposal. This obviously includes the standard Metropolis-Hastings form of the ratio, as well as Barker’s (1965):
$\rho(x,y) = \left(1+\dfrac{\pi(x) q(y|x)}{\pi(y) q(x|y)}\right)^{-1}$
which is known to be less efficient by accepting less often (see, e.g., Antonietta Mira’s PhD thesis). The authors also consider the alternative
$\rho(x,y) = \min(\pi(y)/ q(y|x),1)\,\min(q(x|y)/\pi(x),1)$
which I had not seen earlier. It is a rather intriguing quantity in that it can be interpreted as (a) a simulation of y from the cutoff target corrected by reweighing the previous x into a simulation from q(x|y); (b) a sequence of two acceptance-rejection steps, each concerned with a correspondence between target and proposal for x or y. There is an obvious caveat in this representation when the target is unnormalised since the ratio may then be arbitrarily small… Yet another alternative could be proposed in this framework, namely the delayed acceptance probability of our paper with Marco and Clara, one special case being
$\rho(x,y) = \min(\pi_1(y)q(x|y)/\pi_1(x) q(y|x),1)\,\min(\pi_2(y)/\pi_1(x),1)$
where
$\pi(x)\propto\pi_1(x)\pi_2(x)$
is an arbitrary decomposition of the target. An interesting remark in the paper is that any Hastings representation can alternatively be written as
$\rho(x,y) = \min(\pi(y)/k(x,y)q(y|x),1)\,\min(k(x,y)q(x|y)/\pi(x),1)$
where k(x,y) is a (positive) symmetric function. Hence every single Metropolis-Hastings is also a delayed acceptance in the sense that it can be interpreted as a two-stage decision.
The second part of the paper considers an extension of the accept-reject algorithm where a value y proposed from a density q(y) is accepted with probability
$\min(\pi(y)/ Mq(y),1)$
and else the current x is repeated, where M is an arbitrary constant (incl. of course the case where it is a proper constant for the original accept-reject algorithm). Curiouser and curiouser, as Alice would say! While I think I have read some similar proposal in the past, I am a wee intrigued at the appear of using only the proposed quantity y to decide about acceptance, since it does not provide the benefit of avoiding generations that are rejected. In this sense, it appears as the opposite of our vanilla Rao-Blackwellisation. (The paper however considers the symmetric version called the independent Markovian minorizing algorithm that only depends on the current x.) In the extension to proposals that depend on the current value x, the authors establish that this Markovian AR is in fine equivalent to the generic Hastings algorithm, hence providing an interpretation of the “mysterious” s(x,y) through a local maximising “constant” M(x,y). A possibly missing section in the paper is the comparison of the alternatives, albeit the authors mention Peskun’s (1973) result that exhibits the Metropolis-Hastings form as the optimum. | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 7, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9039468765258789, "perplexity": 1044.1699004285051}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2018-30/segments/1531676589237.16/warc/CC-MAIN-20180716080356-20180716100356-00245.warc.gz"} |
https://hal-insu.archives-ouvertes.fr/insu-01351962 | # Nonlinear local parallel acceleration of electrons through Landau trapping by oblique whistler mode waves in the outer radiation belt
Abstract : Simultaneous observations of electron velocity distributions and chorus waves by the Van Allen Probe B are analyzed to identify long-lasting (more than 6 h) signatures of electron Landau resonant interactions with oblique chorus waves in the outer radiation belt. Such Landau resonant interactions result in the trapping of ˜1-10 keV electrons and their acceleration up to 100-300 keV. This kind of process becomes important for oblique whistler mode waves having a significant electric field component along the background magnetic field. In the inhomogeneous geomagnetic field, such resonant interactions then lead to the formation of a plateau in the parallel (with respect to the geomagnetic field) velocity distribution due to trapping of electrons into the wave effective potential. We demonstrate that the electron energy corresponding to the observed plateau remains in very good agreement with the energy required for Landau resonant interaction with the simultaneously measured oblique chorus waves over 6 h and a wide range of L shells (from 4 to 6) in the outer belt. The efficient parallel acceleration modifies electron pitch angle distributions at energies ˜50-200 keV, allowing us to distinguish the energized population. The observed energy range and the density of accelerated electrons are in reasonable agreement with test particle numerical simulations.
Document type :
Journal articles
Domain :
Cited literature [35 references]
https://hal-insu.archives-ouvertes.fr/insu-01351962
Contributor : Nathalie Pothier Connect in order to contact the contributor
Submitted on : Tuesday, September 13, 2016 - 5:33:55 PM
Last modification on : Tuesday, October 19, 2021 - 7:01:12 PM
### File
2015GRL_Agapitov2.pdf
Publisher files allowed on an open archive
`
### Citation
O. V. Agapitov, A. V. Artemyev, D. Mourenas, F. S. Mozer, V. Krasnoselskikh. Nonlinear local parallel acceleration of electrons through Landau trapping by oblique whistler mode waves in the outer radiation belt. Geophysical Research Letters, American Geophysical Union, 2015, 42 (23), pp.10,140-10,149. ⟨10.1002/2015GL066887⟩. ⟨insu-01351962⟩
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http://math.stackexchange.com/users/76454/annoys-parrot?tab=reputation | Annoys Parrot
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https://tel.archives-ouvertes.fr/tel-00424399 | # Transition d'Anderson avec des ondes de matière atomiques
Abstract : In three dimensions, the eigenstates of a quantum particle subject to a disordered potential have a transition, called the Anderson transition, between a delocalized regime at low disorder and a localized regime at high disorder. This localization being due to interference, it is easily perturbed by decoherence or interaction between particles, and is therefore difficult to observe. In this paper, we report our theoretical work which has enabled the first experimental observation of the Anderson transition with atomic matter waves.
A cloud of cold atoms exposed to a quasi-periodically pulsed standing-wave realizes a variant of the Kicked Rotor (a paradigm of quantum chaos), analogous to a 3D Anderson model. However, the thermodynamic limit is not accessible experimentally. Interpreting these constraints as similar to finite size effects, we construct a finite-time scaling method to characterize the transition, giving the first unambiguous experimental determination of the critical exponent $\nu$ of the transition, and to confirm that the quasiperiodic Kicked Rotor belongs to the same universality class as the Anderson model. From the self-consistent theory of localization, we calculate the critical state of the system, prediction found in very good agreement with experimental and numerical data.
Keywords :
Document type :
Theses
https://tel.archives-ouvertes.fr/tel-00424399
Contributor : Gabriel Lemarié <>
Submitted on : Thursday, October 15, 2009 - 3:17:24 PM
Last modification on : Friday, March 22, 2019 - 1:32:43 AM
Document(s) archivé(s) le : Tuesday, October 16, 2012 - 12:20:28 PM
### Identifiers
• HAL Id : tel-00424399, version 1
### Citation
Gabriel Lemarié. Transition d'Anderson avec des ondes de matière atomiques. Physique Atomique [physics.atom-ph]. Université Pierre et Marie Curie - Paris VI, 2009. Français. ⟨tel-00424399⟩
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http://aas.org/archives/BAAS/v31n5/aas195/490.htm | AAS 195th Meeting, January 2000
Session 84. Submillimeter Wave Astronomy Satellite
Display, Friday, January 14, 2000, 9:20am-6:30pm, Grand Hall
## [84.03] Implications of SWAS Observations for Water Abundance and Velocity Structure in Molecular Clouds
M.L.N. Ashby, E.A. Bergin, R. Plume (CfA), J.M. Carpenter (CalTech), G.J Melnick, J.R. Stauffer, S.C. Kleiner, B.M. Patten, V. Tolls, Z. Wang, Y.F. Zhang (CfA), P.F. Goldsmith (Cornell U., NAIC), M. Harwit (Cornell U.), N.R. Erickson, J.E. Howe, R.L. Snell (UMass, Amherst), D.A. Neufeld (JHU), D.G. Koch (NASA ARC), R. Schieder, G. Winnewisser (Univ. Köln), G. Chin (NASA GSFC)
Now a year into its mission, the Submillimeter Wave Astronomy Satellite (SWAS) has conducted observations of the 556.9~GHz 11,0arrow10,1 ground-state rotational transition of ortho-{\rm H}2\,16{\rm O} towards numerous molecular clouds and other sources. The fact that the upper state energy of this transition is only 27~K above the ground state, and that it has a relatively high critical density (~\times108 cm-3) makes the 556.9~GHz H2O line an effective tracer of the cold, dense gas in cloud cores. The H2O line profiles obtained by SWAS therefore provide an excellent opportunity to understand the velocity structure and H2O abundance in these environments.
We have developed a Monte Carlo radiative transfer model to help interpret SWAS line profiles and better understand the physical conditions in molecular clouds. The Monte Carlo technique accounts globally for the mechanisms of photon absorption and reemission, unlike simpler (but computationally faster) models like the LVG approximation. Such an approach is particularly useful for the SWAS 556.9~GHz line since the line optical depths are large. We compare model spectra to a variety of SWAS-measured H2O line profiles to show that, together with assumptions about the fractional abundance of H2O, variations in the ratio of large-scale bulk motions to small-scale turbulent motions can affect the spectra in ways that may account for the range of observed profiles. As an illustration of the power of this approach, we present a detailed study of the S140 star forming region.
The SWAS team gratefully acknowledges NASA contract NAS5-30702. | {"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8741225600242615, "perplexity": 12380.432614166457}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2014-49/segments/1416931008289.40/warc/CC-MAIN-20141125155648-00056-ip-10-235-23-156.ec2.internal.warc.gz"} |
http://tavianator.com/2014/ray_triangle.html | # A Beautiful Ray/Triangle Intersection Method
2014-05-23 Tavian Barnes Comments
3D ray/triangle intersections are obviously an important part of much of computer graphics. The Möller–Trumbore algorithm, for example, computes these intersections very quickly. But there is another method that I believe is more elegant, and in some cases allows you to compute the intersection for “free.”
Say your triangle has corners at $A$, $B$, and $C$. If your triangle is not degenerate, those three points define a plane. Writing the vector from $A$ to $B$ as $\overrightarrow{AB} = \overrightarrow{B} - \overrightarrow{A}$, and similarly for $\overrightarrow{AC}$, the normal vector perpendicular to that plane is given by
\overrightarrow{N} = \overrightarrow{AB} \times \overrightarrow{AC}
Since $\overrightarrow{AB}$, $\overrightarrow{AC}$, and $\overrightarrow{N}$ are all linearly independent, they form an alternative basis for all of 3-space. That is, any point $\overrightarrow{p}$ can be represented by a unique triple $\langle u, v, w \rangle$ such that
\vec{p} = u\,\overrightarrow{AB} + v\,\overrightarrow{AC} + w\,\overrightarrow{N}.
We can make this space even nicer by translating $A$ to the origin, giving
\vec{p} = u\,\overrightarrow{AB} + v\,\overrightarrow{AC} + w\,\overrightarrow{N} + \overrightarrow{A}.
In this space, the three corners of the triangle are at $\langle 0,0,0 \rangle$, $\langle 1,0,0 \rangle$, and $\langle 0,1,0 \rangle$. It is easy to see that a point is within the triangle if and only if $u,v \ge 0$, $u + v \le 1$, and $w = 0$.
To transform a point $(x,y,z)$ into this nicer space, we can use an affine change of basis matrix
P = \begin{bmatrix}
\overrightarrow{AB} & \overrightarrow{AC} & \overrightarrow{N} & \overrightarrow{A} \\
0 & 0 & 0 & 1
\end{bmatrix}^{-1}.
A line defined by $\overrightarrow{o} + t\,\overrightarrow{n}$ can thus be transformed into the new space by
\begin{aligned}
\begin{bmatrix}
\mathrlap{o_u}\hphantom{n_u} \\
\mathrlap{o_v}\hphantom{n_v} \\
\mathrlap{o_w}\hphantom{n_w} \\
1
\end{bmatrix}
& =
P\,
\begin{bmatrix}
\mathrlap{o_x}\hphantom{n_x} \\
\mathrlap{o_y}\hphantom{n_y} \\
\mathrlap{o_z}\hphantom{n_z} \\
1
\end{bmatrix} \\
\begin{bmatrix}
n_u \\
n_v \\
n_w \\
0
\end{bmatrix}
& =
P\,
\begin{bmatrix}
n_x \\
n_y \\
n_z \\
0
\end{bmatrix}
\end{aligned}
Solving for the intersection point is easy:
\begin{aligned}
t & = -o_w/n_w \\
u & = o_u + t\,n_u \\
v & = o_v + t\,n_v
\end{aligned}
And as above, this can be quickly checked with $u, v \ge 0$, $u + v \le 1$ (and $t \ge 0$ to only count intersections “in front” of the ray).
The beauty of this method is that often, objects are already associated with a transformation matrix, so if you left-multiply that matrix by $P$, the change of basis is performed for free at the same time as other transformations, and only the short block above is needed to actually perform the intersection test. At a cost of 1 division, 2 multiplications, 2 or 3 additions, and some comparisons, that's about as fast as possible without special-casing triangles versus other objects.
Of course, if you're working with lots of triangles (a mesh, for example), you can save memory and time by not associating a transformation matrix with each triangle. In that case, other algorithms such as the one linked above may be faster as they can avoid the two matrix multiplications.
An implementation of this method can be seen here in my ray tracer Dimension.
# Comments
Raphael 2014-08-09
I'm a bit confused about the "cost of 1 division, 2 multiplications, 2 or 3 additions, and some comparisons". Don't you still have to multiply each ray by the matrix P? So even if P is precomputed and stored ahead of time, that's still 16 multiplications and 12 additions, plus the computations of t,u, and v.
Tavian Barnes 2014-08-10
That's in the case that "objects are already associated with a transformation matrix," in which case you have to do a matrix-ray multiplication anyway, so it doesn't count against you. Also I think you've underestimated the cost of a matrix-ray multiplication, it ought to be 18 multiplications and 15 additions.
Vladimir 2017-01-18
Hi! I wonder what is nw is 0? I watched sources from the dimension repo, that case is not handled at all:
https://tavianator.com/cgit/dimension.git/tree/libdimension/triangle.c?id=21137f8eaae886c034f62e18e6039cc48f09993e
Could you please explain what to do if nw is 0?
Tavian Barnes 2017-01-31
Geometrically, if $n_w$ is zero, then the line is exactly parallel to the plane of the triangle. For this degenerate case, it's easiest to just return "no intersection." There are a few sub-cases:
• $o_w = 0$: Then we'll have $t = \mathrm{NaN}$, so $t \ge 0$ fails and we return false
• $o_w > 0$: We'll have $t = -\infty$, so again $t \ge 0$ fails and we return false
• $o_w < 0$: We get $t = \infty$. Depending on $n_u$ and $n_v$,
• $n_u < 0$ or $n_v < 0$: Then $u = -\infty$, $v = -\infty$, so at least one of $u \ge 0$ or $v \ge 0$ fails and we return false
• $n_u = 0$ or $n_v = 0$: Results in $u = \mathrm{NaN}$ or $v = \mathrm{NaN}$, so again one of $u \ge 0$ or $v \ge 0$ fails and we return false
• $n_u > 0$ and $n_v > 0$: That means $u = v = \infty$, so $u + v \le 1$ fails and we return false
Without explicitly handling the $n_w = 0$ case, the properties of IEEE floating point arithmetic have given us the desired behaviour in all cases. | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8603898882865906, "perplexity": 591.2329206528054}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": false}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2020-34/segments/1596439737225.57/warc/CC-MAIN-20200807202502-20200807232502-00558.warc.gz"} |
https://socratic.org/questions/how-would-you-balance-this-equation-pb-no-3-2-pb-no-2-no-2-o-2 | Chemistry
Topics
# How would you balance this equation: ?Pb(NO_3)_2 → ?Pb + ?NO_2 + ?O_2?
Mar 14, 2017
$P b {\left(N {O}_{3}\right)}_{2} \rightarrow P b + O 2 + 2 N {O}_{2}$
#### Explanation:
To balance this reaction first we have to see the number of moles of each element.
$P b {\left(N {O}_{3}\right)}_{2} \rightarrow P b + {O}_{2} + N {O}_{2}$
(Pb = 1) (Pb = 1)
$\left(N = 2\right)$ $\left(O = {\cancel{4}}^{6}\right)$
(O = 6 ) $\left(N = {\cancel{1}}^{2}\right)$
First try adding 3 as the coefficient in front of ${O}_{2}$ and 2 in front of $N {O}_{2}$ but that will be wrong as 2NO2 has 4 oxygen atoms which we dont have, so to make a balanced equation we must remove 3 from O2 and add 2 in front of $N {O}_{2}$
= $P b {\left(N {O}_{3}\right)}_{2} \rightarrow P b + O 2 + 2 N {O}_{2}$
##### Impact of this question
250 views around the world | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 9, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.5573661923408508, "perplexity": 1545.465868084393}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2019-51/segments/1575540491491.18/warc/CC-MAIN-20191206222837-20191207010837-00328.warc.gz"} |
https://proofwiki.org/wiki/Category:Symbols/Beta | # Category:Symbols/Beta
This category contains pages containing definitions of the Greek letter $\Beta$ (lowercase: $\beta$).
The main page of this category is Symbols:Beta.
## Pages in category "Symbols/Beta"
The following 2 pages are in this category, out of 2 total. | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8265253901481628, "perplexity": 3643.997873200895}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 5, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2021-43/segments/1634323588153.7/warc/CC-MAIN-20211027115745-20211027145745-00150.warc.gz"} |
https://www.physicsforums.com/threads/diff-eqs-cant-get-a-reasonable-answer.823746/ | Diff Eqs: can't get a reasonable answer
Tags:
1. Jul 17, 2015
kostoglotov
1. The problem statement, all variables and given/known data
My issues arise in part (b) but cause me to doubt my solution to part (a) as well.
2. Relevant equations
3. The attempt at a solution
$$\frac{dx}{dt} = k(a-x)(b-x)$$
$$\int \frac{1}{(a-x)(b-x)} dx = k \int dt$$
Use partial fraction decomposition on LHS
$$\frac{1}{(a-x)(b-x)} = \frac{A}{a-x}+\frac{B}{b-x}$$
$$A(b-x) + B(a-x) = 1$$
Let x = b
$$B(a-b) = 1 \ \ B = \frac{1}{a-b}$$
Let x = a
$$A(b-a) = 1 \ \ A = \frac{1}{b-a} = \frac{-1}{a-b}$$
$$\int \frac{1}{(a-x)(b-x)} dx = \int \frac{1}{(a-b)(b-x))} - \frac{1}{(a-b)(a-x)} dx$$
$$= \frac{1}{a-b} \left[ -\ln{|b-x|} + \ln{|a-x|} \right] = \frac{1}{a-b} \ln{\frac{|a-x|}{|b-x|}} = k(t+C)$$
$$\ln{\frac{|a-x|}{|b-x|}} = (a-b)k(t+C)$$
$$\frac{|a-x|}{|b-x|} = e^{(a-b)kC}e^{(a-b)kt}$$
Now let's skip a few steps and get
$$\frac{a-x}{b-x} = Ke^{(a-b)kt}$$
already here I can see problems with part (b), as when a = b, $\frac{a-x}{b-x} = K$
But if we carry on with some algebra from the last step I arrive at
$$x(t) = \frac{bKe^{(a-b)kt}-a}{Ke^{(a-b)kt}-1}$$
and if x(0) = 0 then
$$K = \frac{a}{b}$$
and then
$$x(t) = \frac{a(e^{(a-b)kt}-1)}{\frac{a}{b}e^{(a-b)kt}-1}$$
Now, if a = b x(t) = 0...
Where have I gone wrong?
edit: or is my answer to part (a) correct, and I need to return to the very beginning of the sequence and assume a = b in order to solve (b), thus, the solution to part (a) only holding for the condition that $a \neq b$?
2. Jul 17, 2015
fzero
I didn't go through all of the algebra, but your solution to (a) looks ok. If $a=b$, the partial fraction decomposition is not valid, but you can instead integrate $1/(a-x)^2$ directly. The solution will have a different functional form involving a reciprocal of $t$ rather than an exponential function.
3. Jul 17, 2015
kostoglotov
Thanks, I'm still trying to get an intuitive handle on diff eqs. That's why I was getting frustrated. Because my technical skills in everything required in this problem are fine, so not being able to find a mistake, I thought maybe I'd missed something big at the beginning...which it turns out I did I guess.
Domains become really important to consider when modelling with diff eqs then right?
4. Jul 18, 2015
Ray Vickson
You have gone wrong putting $a = b$ in your $x(t)$ formula because you will have the dreaded (and illegal) form $0/0$. Either you need to put $a = b$ before solving the DE, or else you need to look at $\lim_{b \to a} x(t)$ after you have solved it. When you do it the latter way you do not get $x(t) = 0$.
Last edited: Jul 18, 2015
5. Jul 18, 2015
DeldotB
Kostoglotov,
I have arrived at your same solution. Partial fractions are still valid since we are asssuming a does not equal b in part a. Try letting a=b and integrating just using a substitution for part b. It wouldn't make sense to let a=b with the equation just derived since x(t)= 0 for all t.
Edit: Ahh Ray beat me to the punch. I second that, re do from the beginning letting a=b
6. Jul 18, 2015
epenguin
If you go back to your equations for A and B you already see it's trouble if a = b.
In fact no one would ask you to expand 1/(x - a)2 as a partial fraction - there is no way to make it identical to any constant divided by (x - a).
7. Jul 18, 2015
Zondrina
The domain is always important. Consider the homogeneous Cauchy-Euler equation:
$$ax^2y'' + bxy' + cy = 0$$
In standard form:
$$y'' + \frac{b}{a x} y' + \frac{c}{a x^2}y = 0$$
$x = 0$ would be a regular singular point because the solution may be undefined at $x = 0$. We would then need to seek solutions for $x > 0$ and $x < 0$ individually.
To derive a solution $\forall x \neq 0$, then the absolute value would be required. | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 2, "mathjax_display_tex": 2, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9160569310188293, "perplexity": 551.8783996987232}, "config": {"markdown_headings": false, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2018-13/segments/1521257647545.54/warc/CC-MAIN-20180320205242-20180320225242-00192.warc.gz"} |
https://www.physicsforums.com/threads/liebniz-notation.183536/ | # Homework Help: Liebniz notation
1. Sep 8, 2007
### ehrenfest
1. The problem statement, all variables and given/known data
In many physics books I have seen the treatment of dx/dy as a fraction dx over dy. For example, if you have an expression for dx and an expression for dy then you just put dx in the numerator and dy in the denominator to get the derivative. THis is also done in the separation of variables technique.
I have heard that this is not mathematically sound. Is there a rule for when you can treat Liebniz notation like fractions?
2. Relevant equations
3. The attempt at a solution
2. Sep 8, 2007
### Gokul43201
Staff Emeritus
3. Sep 9, 2007
### HallsofIvy
The "Liebniz form" for a derivative: dy/dx is NOT a fraction but it can always be treated like one. The derivative is a limit of a fraction. To prove that any "fraction property" works for a derivative, go back before the liimit, use the fraction property, then take the limit.
That's why the notion of "differentials", defining "dy" and "dx", if only symbolically, that Gokul43201 was referring to, is so powerful.
4. Sep 9, 2007
### arildno
Remember, though, that the derivative is NOT in general a fraction; this is highlighted by the behaviour of partial derivatives:
let F(x,y) be a differentiable function; x=X(y).
Thereby, we have:
$$\frac{dF}{dy}=\frac{\partial{F}}{\partial{x}}\frac{dX}{dy}+\frac{\partial{F}}{\partial{y}}$$
Here, the relationships between the pseudo-fractions is NOT that which might be "predicted" by common fraction arithmetic. | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 1, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9532685279846191, "perplexity": 1378.9317415268163}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2018-30/segments/1531676591543.63/warc/CC-MAIN-20180720061052-20180720081052-00111.warc.gz"} |
https://aviation.stackexchange.com/questions/16976/what-does-clear-of-clouds-mean-in-faa-far-part-103 | # What does “clear of clouds” mean in FAA FAR part 103?
In FAR part 103 when they are talking about visibility requirements for flying an ultralight, sometimes instead of giving exact distances, they will just say "clear of clouds".
For example:
Minimum
flight
visibility
Flight altitudes /1/ Minimum distance from clouds
1,200 feet or less above the
surface regardless of MSL
altitude:
(1) Within controlled airspace 3 500 feet below, 1,000 feet above, 2,000 feet horizontal.
(2) Outside controlled airspace 1 Clear of clouds.
Or here:
Flight
Airspace visibility Distance from clouds
Class G:
1,200 feet or less above the
surface (regardless of MSL
altitude) 1 statute mile Clear of clouds.
More than 1,200 feet above the
surface but less than 10,000
feet MSL 1 statute mile 500 feet below.
1,000 feet above.
2,000 feet horizontal.
What does "Clear of Clouds" mean in this context? Just that I should remain clear of the clouds, or does it mean that the sky must be clear of clouds in the defined space?
And if it does just mean I need to stay "clear of the clouds", how exactly is that defined? 1000ft? 100ft? 10ft? What exactly?
• keep clear of them. don't go in them. – Octopus Jul 17 '15 at 18:40
Clear of clouds means you should not fly through clouds. You may get as near as comfortable to clouds, but flying into a cloud is still prohibited. There is no definition with a particular distance that I am aware of. | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.6717745065689087, "perplexity": 6657.311856102903}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2019-47/segments/1573496669276.41/warc/CC-MAIN-20191117192728-20191117220728-00199.warc.gz"} |
https://kimsereylam.com/fsharp/2016/03/18/websharper-warp.html | By Kimserey Lam with
# Websharper Warp
Mar 18th, 2016 - written by Kimserey with .
Scripting quick prototypes in WebSharper can sometimes be troublesome. If for each prototype, a new project has to be created or code needs to be commented/uncommented, it can become quite demotivating as too many steps are required. In F#, .fsx files are a great tool to script disposable code. Write some isolated functions, run on FSI and then forget about it.
With WebSharper, it is possible to script a complete sitelets in .fsx files using WebSharper.Warp https://github.com/intellifactory/websharper.warp.
In this post, I will show you how you can setup a project in order to use Warp efficiently to create sitelet prototypes. Building with .fsx is a huge advantage. It allows us to have multiple files containing completely isolated sitelets all within the same project. Using one line command, we can boot up a sitelet to test it quickly which makes it ideal for prototyping.
The code here can be found on Github https://github.com/Kimserey/WarpTemplate.
## Get WebSharper.Warp
There are two ways to get WebSharper.Warp. The first way is through Nuget and the second way is through Paket.
For anything related to .fsx, I would strongly recommend using Paket.
If you are unfamiliar with Paket you can read the doc here or checkout an older post I made about it. So we will be using Paket here.
Run the Paket command:
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This should install Warp in your \packages folder. It should also install all the references of Warp including WebSharper, WebSharper.UI.Next and others. Warp also comes with an extra folder \tools where you should find reference-nover.fsx. This file contains all the reference links to be loaded from your .fsx file so that you don’t need to reference everything by yourself. You just need to load reference-nover.fsx at the head of your .fsx:
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#I "../packages/"
This is one of the reason why I recommended to use Paket. If we were to use Nuget, the path would break each time WebSharper is updated because Nuget puts the version number in the path. Another reason is that we don’t need to add the reference to any project. We just need the libraries to be downloaded in order for us to reference it from our .fsx.
For the moment, some references are missing from reference-nover.fsx, I’ve made a PR. Until this is merged, you will need to alter reference-nover.fsx to add WebSharper.UI.Next.Templating.dll and Intellifactory.Xml.dll if you want to use the html templates in your sitelets.
Now that we have Warp ready, we can start creating our first sitelet.
## Build a sitelet
Let’s start by creating a very simple sitelet. Create a .fsx file and put the following sitelet in:
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#I "../packages/"
open WebSharper
open WebSharper.JavaScript
open WebSharper.Sitelets
open WebSharper.UI.Next
open WebSharper.UI.Next.Html
open WebSharper.UI.Next.Client
module Remoting =
[<Rpc>]
let sayHello() =
async.Return "Hello!"
[<JavaScript>]
module Client =
let main() =
View.Const ()
|> View.MapAsync Remoting.sayHello
|> Doc.BindView text
module Server =
let site =
Application.SinglePage (fun _->
Content.Page [ client <@ Client.main() @> ])
do Warp.RunAndWaitForInput Server.site |> ignore
To create the sitelet, we use Application.SinglePage which is a helper to boot SPA with a single endpoint.
The interesting part is Warp.RunAndWaitForInput which takes our sitelet as argument. If you run this code in FSI, it will boot a selfhosted server on http://localhost:9000/ (by default).
This is fantastic! With just one single small isolated .fsx file we can boot a complete server and start serving pages. We could use another function than Application.SinglePage and have a full-blown sitelet with multiple endpoints if we wanted.
Now sending code to FSI is useful when we want to run part of the .fsx but in our case right now, we just evaluate the complete .fsx every time. So to make this task easier, we can create a buildAndRun.cmd file which will execute the script so that we can easily restart the sitelet without having to manually sent the code to the FSI. It consists of one single command line.
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C:\"Program Files (x86)"\"Microsoft SDKs"\F#\4.0\Framework\v4.0\fsi.exe %*
And we run this command in the command prompt:
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buildAndRun.cmd Simple_Sitelet.fsx
This was a simple example. But we can have more complex sitelets. For example, we can also reference external resources.
Say we want to add Bootstrap, one way to do it is by using the html template.
Remember you need to add the libraries in reference-nover.fsx
We can create a html file index.html which loads Bootstrap and place it at the root:
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<!DOCTYPE html>
<html lang="en">
<meta charset="utf-8" />
<meta name="viewport" content="width=device-width, initial-scale=1.0" />
<title>-</title>
<meta name="generator" content="websharper" data-replace="scripts" />
<link href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.6/css/bootstrap.min.css" rel="stylesheet" integrity="sha384-1q8mTJOASx8j1Au+a5WDVnPi2lkFfwwEAa8hDDdjZlpLegxhjVME1fgjWPGmkzs7" crossorigin="anonymous" />
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.6/js/bootstrap.min.js" integrity="sha384-0mSbJDEHialfmuBBQP6A4Qrprq5OVfW37PRR3j5ELqxss1yVqOtnepnHVP9aJ7xS" crossorigin="anonymous"></script>
<body>
<div data-replace="body">
</div>
</body>
</html>
And then use it as template with our sitelet:
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module Server =
type Page = { Body: Doc list }
let template =
Content.Template<Page>(__SOURCE_DIRECTORY__ + "/index.html")
.With("body", fun x -> x.Body)
let site =
Application.SinglePage (fun _ ->
Content.WithTemplate template
{ Body = [ client <@ Client.main() @> ] })
We now have all the ingredients to create powerful sitelet within a .fsx file:
• RPCs
• External resources
• JS compilation
• Boot on Owin selfhost
## Benefits
The major benefit is that it makes prototyping much easier. When I started to use WebSharper, I used to create new projects each time I had to test something.
It was slow and demotivating. I just kept the same project and every time I had to test something, I would delete the previous code.
Now I don’t do that anymore as with WebSharper.Warp, only one .fsx file needs to be created. It is easy and quick and you can be up and running a full sitelet in a matter of seconds. This makes prototyping much more enjoyable and combined with the build script, it is quick and easy to iterate.
## Conclusion
Today we saw how we could use WebSharper.Warp in a very efficient way. Prototyping is one of the best way to take advantage of Warp since it is so easy to get started! I hope you will try it and let me know if you have other tricks to make your journey with WebSharper even more enjoyable. As usual, if you have any comments please leave it here or hit me on Twitter @Kimserey_Lam. Thanks for reading!
Designed, built and maintained by Kimserey Lam. | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.32380199432373047, "perplexity": 3647.521146577835}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2019-39/segments/1568514574665.79/warc/CC-MAIN-20190921211246-20190921233246-00253.warc.gz"} |
http://fr.mathworks.com/help/physmod/sps/powersys/ref/parallelrlcbranch.html?s_tid=gn_loc_drop&requestedDomain=fr.mathworks.com&nocookie=true | # Parallel RLC Branch
Implement parallel RLC branch
## Library
Fundamental Blocks/Elements
## Description
The Parallel RLC Branch block implements a single resistor, inductor, and capacitor or a parallel combination of these. Use the Branch type parameter to select elements you want to include in the branch.
Negative values are allowed for resistance, inductance, and capacitance.
## Dialog Box and Parameters
Branch type
Select the elements you want to include in the branch. The R letter defines the resistor, the L letter defines the inductor, and the C letter defines the capacitor. Select Open circuit to define an open circuit (R=inf, L=inf, C=0). Only existing elements are displayed in the block icon.
Resistance
The branch resistance, in ohms (Ω). The Resistance parameter is not visible if the resistor element is not specified in the Branch type parameter.
Inductance L
The branch inductance, in henries (H). The Inductance parameter is not visible if the inductor element is not specified in the Branch type parameter.
Set the initial inductor current
If selected, the initial inductor current is defined by the Inductor initial current parameter. If not selected, the software calculates the initial inductor current in order to start the simulation steady-state.
The Set the initial inductor current parameter is not visible and have no effect on the block if the inductor element is not specified in the Branch type parameter.
Inductor initial current (A)
The initial inductor current used at the start of the simulation. The Inductor initial current parameter is not visible and have no effect on the block if the inductor is not modeled and if the Set the initial inductor current parameter is not selected.
Capacitance C
The branch capacitance, in farads (F). The Capacitance parameter is not visible if the capacitance element is not specified in the Branch type parameter.
Set the initial capacitor voltage
If selected, the initial capacitor voltage is defined by the Capacitor initial voltage parameter. If not selected, the software calculates the initial capacitor voltage in order to start the simulation in steady-state.
The Set the initial capacitor voltage parameter is not visible and have no effect on the block if the capacitor element is not specified in the Branch type parameter.
Capacitor initial voltage (V)
The initial capacitor voltage used at the start of the simulation. The Capacitor initial voltage parameter is not visible and have no effect on the block if the capacitor is not modeled and if the Set the initial capacitor voltage parameter is not selected.
Measurements
Select Branch voltage to measure the voltage across the Parallel RLC Branch block terminals.
Select Branch current to measure the total current (sum of R, L, C currents) flowing through the Parallel RLC Branch block.
Select Branch voltage and current to measure the voltage and the current of the Parallel RLC Branch block.
Place a Multimeter block in your model to display the selected measurements during the simulation. In the Available Measurements list box of the Multimeter block, the measurement is identified by a label followed by the block name.
Measurement
Label
Branch voltage
Ub:
Branch current
Ib:
## Example
The power_paralbranch example is used to obtain the frequency response of an eleventh-harmonic filter (tuned frequency at 660 Hz) connected on a 60 Hz power system:
The network impedance in the Laplace domain is
$Z\left(s\right)=\frac{V\left(s\right)}{I\left(s\right)}=\frac{RLC{s}^{2}+Ls+R}{LC{s}^{2}+RCs}.$
To obtain the frequency response of the impedance you have to get the state-space model (A B C D matrices) of the system.
This system is a one input (Is) and one output (Vs) system.
Note If you have Control System Toolbox™ software installed, you can get the transfer function Z(s) from the state-space matrices and the bode function.[A,B,C,D] = power_analyze('power_paralbranch'); freq = logspace(1,4,500); w = 2*pi*freq; [Zmag,Zphase] = bode(A,B,C,D,1,w); subplot(2,1,1) loglog(freq,Zmag) grid title('11th harmonic filter') xlabel('Frequency, Hz') ylabel('Impedance Z') subplot(2,1,2) semilogx(freq,Zphase) xlabel('Frequency, Hz') ylabel('phase Z') grid You can also use the Impedance Measurement block and the Powergui block to plot the impedance as a function of frequency. | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 1, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.943053662776947, "perplexity": 1541.483569728808}, "config": {"markdown_headings": true, "markdown_code": false, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 20, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2016-40/segments/1474738661778.22/warc/CC-MAIN-20160924173741-00278-ip-10-143-35-109.ec2.internal.warc.gz"} |
http://math.stackexchange.com/questions/10292/congruency-and-congruent-classes | # Congruency and Congruent Classes
so studying for my midterm on Tuesday (intro to abstract algebra). The topics on the exam are Division Algorithm, Divisibility, Prime Numbers, FTA, Congruency, Congruent Classes and very brief introduction to rings.
I was reading a few theorems about Congruency and have a couple of questions.
I want to know what a "congruent class" is. My notes say "the congruence class of a modulo n" is a set:
$\left\{ \text{all } b \in \mathbb{Z} | b \equiv a \pmod{n} \right\}$ which is also saying $\left\{ \text{all } a + kn \in \mathbb{Z} | k \in \mathbb{Z} \right\}$
okay so got that. I just wrote it for some people who might need a refreshed (it is a 3rd undergrad course after all).
So in my notes our professor has a following example: $\left[ 60 \right]_{17} = \left[ 43\right]_{17}$
1) so the way I figured this out is that to check if they are equivalent, we subtract 60-43 and see if that is a multiple of n = 17. Is this how you can check if they are equal classes? If not, is there a better way to do so?
2) A certain theorem states: Let $n \in \mathbb{Z}_+; a, b \in \mathbb{Z}$ and $gcd(a,n) = d$ then $[a]x=[b]$ has exactly $d$ solutions. My question here is that is x a congruence class or a random integer? What is x and how do I solve for it?
3) Is it true that if we are in $\mathbb{Z}_{12}$ then $[7]x=[11]$ can be rewritten as $7x \equiv 11 \pmod{12}$? If so, would finding the solution be similar to solution in this question
Thankyou. I am just very confused about congurency and stuff. I understand the theorems but I am hoping someone would give me an "easy" explanation of what is going on. I still don't know the difference between circle plus and regular plus except that circle plus has to satisfy certain axioms. Am I right?
-
"I am just very confused about congurency and stuff." Don't worry, everyone is at first. Now, at least on 1) and 3) you are quite right. The method you presented in 1) is a very simple and straightforward one, and 3) can be attacked with the methods in the linked to question. For 2), I'm having some trouble with the Latex here, but it seems that $x$ is a variable, representing an integer. Actually, if you work through your 3), then you should have a concrete example of the theorem in 2) in action. – Gunnar Þór Magnússon Nov 14 '10 at 20:30
There is a much more general definition of congruence classes, but I shall restrict to the one that is sufficient for your course. Given any integer $n$ the only possible remainders that we can get when we divide an integer $a$ by $n$ are $0,1,...,n-1$. Each set of integers which leave the same remainder on division by $n$ form what is called as a congruence class modulo $n$. All such congruence classes are mutually disjoint since a number can leave only one remainder on division by $n$. Their union is the set of all integers. Each integer in any given congruence class is said to be a representative of the class.
To check whether two integers are in the same class, we check their difference and see if it is divisible by $n$ (since the remainders of these integers cancel out when we divide by $n$). So your approach to your first question is right.
For the second question, $x$ is indeed a congruence class, since otherwise the equation does not make sense. We can define operations on the congruence classes by the correponding operations on their representatives. Its easy to check these are well defined.
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So can you explain why [17]_8 = [1]_8? if we divide 8 by 17, the remainder is 12. if we divide 8 by 1 the remainder is 0. Yet my notes say they are the same class. – Tyler Hilton Nov 14 '10 at 20:55
You need to take the difference of representatives and divide the difference. In this case, $17-1=16$ is divisible by $8$. Alternately, when you divide $17$ by $8$ the remainder is $1$. – Timothy Wagner Nov 14 '10 at 21:02
@Tyler Hilton: You are interpreting it wrong. For $[17]_8$, you divide $17$ by $8$, with remainder $1$ (If you divide $8$ by $17$, then the remainder is $8$, not $12$!). Then for $[1]_8$ you divide $1$ by $8$, which gives you a remainder of $1$ as well. – Arturo Magidin Nov 14 '10 at 22:46
Okay, let's start from the beginning. You define the congruence class of $a$ as: \begin{equation*} [a]_n = \{ b\in\mathbb{Z}\mid a\equiv a\pmod{n}\}. \end{equation*} Now, what does $a\equiv b\pmod{n}$ mean? It means that $n$ divides $a-b$, or equivalently, that $a$ and $b$ leave the same remainder when you divide them by $n$. Considering the last of the conditions, notice that:
1. Since each number leaves the same remainder as itself when divided by $n$, $a\equiv a \pmod{n}$ for all $a$.
2. If $a$ leaves the same remainder as $b$ when divided by $n$, then $b$ leaves the same remainder as $a$ when divided by $n$. So if $a\equiv b\pmod{n}$, then $b\equiv a \pmod{n}$.
3. If $a$ leaves the same remainder as $b$, and $b$ leaves the same remainder as $c$, then $a$ and $c$ leave the same remainder as well. So if $a\equiv b\pmod{n}$ and $b\equiv c\pmod{n}$, then $a\equiv c\pmod{n}$.
That means that: \begin{equation*} [a]_{n} = [b]_n\Longleftrightarrow a\equiv b\pmod{n}. \end{equation*} Why? Well, suppose the congruence classes are the same. Since $a\in[a]_n=[b]_n$, that means that $b\equiv a \pmod{n}$ (since $a\in[b]_n$), so $a\equiv b\pmod {n}$. That proves that if the classes are equal, then $a\equiv b\pmod{n}$.
Conversely, suppose that $a\equiv b\pmod{n}$. How do we prove that $[a]_{n}=[b]_{n}$? Since they are sets, the usual way is to show that each is contained in the other. If $c\in[a]_n$, then $a\equiv c\pmod{n}$ by definition; since we also have $b\equiv a\pmod{n}$ (since $a\equiv b\pmod{n}$ is our assumption), then $b\equiv c\pmod{n}$, so $c\in[b]_n$. Therefore, every that is in $[a]_{n}$ is also in $[b]_n$, so $[a]_n\subseteq [b]_n$. For the converse inclusion, if $c\in[b]_n$, then $b\equiv c\pmod{n}$, and since we also have $a\equiv b\pmod{n}$, then $a\equiv c \pmod{n}$ so $c\in[a]_n$. Therefore, $[b]_n\subseteq [a]_n$. Since we have the two inclusions, we conclude that $[a]_n=[b]_n$.
We also have the following, which is perhaps more surprising: \begin{equation*} [a]_n\cap[b]_n\neq\emptyset\Longleftrightarrow [a]_n=[b]_n. \end{equation*} That is: the only way the class of $a$ and the class of $b$ have anything in common is if they are identical. Why? Well, if they are identical they certainly have nonempty intersection, since the class of $a$ always includes at least $a$. And conversely, if $c\in[a]_n\cap[b]_n$, then $a\equiv c\pmod{n}$ and $b\equiv c\pmod{n}$, from which we conclude that $a\equiv b\pmod{n}$, so $[a]_n=[b]_n$ by what we just finished proving.
On to your questions:
(1) How do we check if $[a]_{17} = [b]_{17}$? Precisely the way you did it: the classes are equal if and only if $a\equiv b \pmod{17}$. How do you check if $a\equiv b\pmod{17}$? By checking to see if $17$ divides $a-b$. So how do you check in general whether $[a]_n=[b]_n$? You check to see if $a-b$ is a multiple of $n$. If it is, then the classes are equal. If $a-b$ is not a multiple of $n$, then they are not equal, and in fact they are disjoint.
There are other ways: for example, if you could show that $[60]_{17}$ and $[43]_{17}$ have any element in common, then you would be able to conclude that they are equal. Sometimes it may be simpler to see that $[a]_n$ and $[b]_n$ have some element in common than to check if $n$ divides $a-b$; but the standard way of checking is to see whether $n$ divides $a-b$, just as you did.
(2) What you have is an equation in which $x$ is an unknown. You are really looking for all solutions to the congruence \begin{equation*} ax \equiv b \pmod {n} \end{equation*} That is, all integers $x$ that make the congruence true. For example, $x=3$ is a solution to \begin{equation*} 2x \equiv 1 \pmod{5} \end{equation*} because $(2)(3)= 6\equiv 1 \pmod{5}$. In fact, because $3$ is a solution, so is $3+5k$ for any integer $k$; that is, any element in $[3]_5$ is a solution, since $3$ is a solution. So the solutions will actually be a collection of congruence classes.
Moreover, if we replace $2$ in the equation with $7$, so that we are trying to solve $7x\equiv 1 \pmod{5}$, then anything which was a solution to $2x\equiv 1\pmod{5}$ is still a solution, and any solution to the first one is still a solution to the new congruence; why? because $2x\equiv 7x\pmod{5}$ for all $x$, as $2x-7x = -5(x)$ is always a multiple of $5$. So we can replace $2$ with any element of $[2]_5$ and not change the solutions. Likewise, we can replace $1$ with any element of $[1]_5$ and not change the solutions. So it's almost as if instead of trying to solve the single congruence \begin{equation*} 2x \equiv 1 \pmod{5} \end{equation*} we are trying to solve the equation \begin{equation*} [2]_5 x = [1]_5 \end{equation*} So that's why you have written $[a]x=[b]$. That really means the congruence $ax\equiv b \pmod{n}$.
What you wrote, however, is incorrect. You are missing a clause: the congruence will have $d$ solutions if $d$ divides $b$. Otherwise, it's not going to have any. For an easy example, consider the congruence $2x\equiv 1 \pmod{4}$. Then $\gcd(2,4)=2$, but there are no solutions to the congruence, because $2x$ is always even, so $2x-1$ is always odd, so $4$ never divides $2x-1$.
Now, how do you solve a congruence $ax\equiv b\pmod{n}$ when $\gcd(a,n)$ divides $b$? let $d=\gcd(a,n)$. Then we can write $a=da'$, $b=db'$, and $n=dn'$. Then $ax\equiv b\pmod{n}$ if and only if $n$ divides $ax-b$. But $ax-b = d(a'x - b')$, and $dn'$ divides $d(a'x-b')$ if and only if $n'$ divides $a'x-b'$, if and only if $a'x\equiv b'\pmod{n'}$. So if we can solve a congruence when $\gcd(a,n)=1$, then we can solve any congruence where $\gcd(a,n)$ divides $b$
So, how do you solve a system $ax \equiv b\pmod{n}$ when $\gcd(a,n)=1$ (which will of course divide $n$)? Since $\gcd(a,n)=1$, then we can write $n$ as a linear combination of $a$ and $n$, $1=ar+ns$ for some integers $r$ and $s$ (for example, using the Euclidean algorithm). Multiplying through by $b$ you get $b=a(rb)+ n(sb)$. That means that $n(sb) = a(rb)-b$, so $a(rb)\equiv b \pmod{n}$, which means that $x=rb$ is a solution. If $y$ is any other solution, then $ay\equiv b\pmod{n}$, and $ax\equiv b\pmod{n}$, so $ax\equiv ay\pmod{n}$, hence $n$ divides $ax-ay=a(x-y)$, and since $\gcd(a,n)=1$, then $n$ divides $x-y$; so if $y$ is any other solution, then $x\equiv y\pmod{n}$. So the only congruence class that is a solution is $[x]_n$.
Now, what about general congruences? Suppose you have $[a]_nx=[b]_n$ and $\gcd(a,n)=d$ divides $b$. Write $a=da'$, $b=db'$, and $n=dn'$. Notice that $\gcd(a',n')=1$. Find a solution $x_0$ to $[a']_{n'}x=[b']_{n'}$. Then $n'$ divides $a'x_0 -b'$, so $dn'=n$ divides $d(a'x_0-b') = da'x_0-db' = ax_0-b$. So $x_0$ is also a solution to the original problem. If $y$ is any other solution, then as before we get that $n$ divides $a(x_0-y)$; so $dn'$ divides $da'(x_0-y)$, hence $n'$ divides $a'(x_0-y)$, and since $\gcd(a',n')=1$, then $n'$ divides $x_0 - y$; that is, $y\equiv x_0\pmod{n'}$, so $y=x_0+kn'$ for some $k$. Conversely, if $y = x_0+\ell n'$ for some $\ell$, then \begin{equation*} ay = a(x_0+\ell n') = ax_0 + \ell an' = ax_0 + \ell (da')n' = ax_0 + \ell a'(dn') = ax_0 + (\ell a')n, \end{equation*} which says that $ay \equiv ax_0 \pmod{n}$, so $y$ is also a solution. So what are the different solutions? Well, we have $x_0$, $x_0+n'$, $x_0+2n'$, $x_0+3n',\ldots, x_0+(d-1)n'$. All of these are not congruent to one another modulo $n$; the "next" one, however, will be $x_0+dn' = x_0+n$, which is congruent to $x_0$ modulo $n$. So the only distinct congruence classes that are solutions are $[x_0]_n$, $[x_0+n']_n,\ldots,[x_0+(d-1)n']_n$, giving you exactly $d$ distinct classes that are solutions to $[a]_nx=[b]_n$.
To see this in practice, take $n= 77$, $a=21$, and $b=14$. We want to solve the system $[21]_{77} x = [9]_{77}$ Since $\gcd(77,21)=7$ divides $b$, the system has solutions; in fact, it has $7$ different congruence classes modulo $77$ as solutions.
So, we write $21 = 7\cdot 7$, $14 = 7\cdot 2$, $77 = 7\cdot 11$. And we first solve the system $[3]_{11}x=[2]_{11}$. To do this, we write $1$ as a linear combination of $3$ and $11$, like so: $1 = 3(4) - 11(1)$. Then multiply by $2$ to get $2 = 3(8)-11(2)$. So $x_0=8$ is a solution (indeed, $3(8)=24\equiv 2\pmod{11}$). Now going back to the original congruence, we take $x_0$ and we add multiples of $11$ (why $11$? Because $n=77$ is $7\cdot 11$, and $7$ is the $d$ from before) until we have our $7$ different solutions. So the solutions are: $[8]_{77}$, $[19]_{77}$, $[30]_{77}$, $[41]_{77}$, $[52]_{77}$, $[63]_{77}$, and $[74]_{77}$. You can verify that they all are solutions to $[21]_{77}x = [14]_{77}$. For example, $21\cdot 41 = 861$, and $[861]_{77}=[14]_{77}$ because $861-14 = 847 = 77\cdot 11$.
(3) Yes: that is exactly the meaning of $[a]_nx=[b]_n$; it means $ax\equiv b\pmod{n}$.
Hope this helps, despite the length.
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https://www.lmfdb.org/ModularForm/GL2/Q/holomorphic/65/ | ## Results (1-50 of 178 matches)
Label Dim $A$ Field CM Traces Fricke sign $q$-expansion
$a_{2}$ $a_{3}$ $a_{5}$ $a_{7}$
65.2.a.a $1$ $0.519$ $$\Q$$ None $$-1$$ $$-2$$ $$-1$$ $$-4$$ $+$ $$q-q^{2}-2q^{3}-q^{4}-q^{5}+2q^{6}-4q^{7}+\cdots$$
65.2.a.b $2$ $0.519$ $$\Q(\sqrt{2})$$ None $$-2$$ $$0$$ $$2$$ $$4$$ $-$ $$q+(-1+\beta )q^{2}+\beta q^{3}+(1-2\beta )q^{4}+\cdots$$
65.2.a.c $2$ $0.519$ $$\Q(\sqrt{3})$$ None $$0$$ $$2$$ $$-2$$ $$4$$ $-$ $$q+\beta q^{2}+(1-\beta )q^{3}+q^{4}-q^{5}+(-3+\cdots)q^{6}+\cdots$$
65.2.b.a $6$ $0.519$ 6.0.350464.1 None $$0$$ $$0$$ $$0$$ $$0$$ $$q+(\beta _{3}-\beta _{5})q^{2}+(-\beta _{3}-\beta _{4})q^{3}+(-2+\cdots)q^{4}+\cdots$$
65.2.c.a $6$ $0.519$ 6.0.5089536.1 None $$0$$ $$-4$$ $$0$$ $$0$$ $$q-\beta _{5}q^{2}+(-1-\beta _{1})q^{3}+(-2+\beta _{3}+\cdots)q^{4}+\cdots$$
65.2.d.a $2$ $0.519$ $$\Q(\sqrt{-1})$$ None $$-2$$ $$0$$ $$-2$$ $$0$$ $$q-q^{2}+iq^{3}-q^{4}+(-1+i)q^{5}-iq^{6}+\cdots$$
65.2.d.b $2$ $0.519$ $$\Q(\sqrt{-1})$$ None $$2$$ $$0$$ $$2$$ $$0$$ $$q+q^{2}+iq^{3}-q^{4}+(1-i)q^{5}+iq^{6}+\cdots$$
65.2.e.a $4$ $0.519$ $$\Q(\sqrt{-3}, \sqrt{5})$$ None $$-1$$ $$0$$ $$4$$ $$-4$$ $$q-\beta _{1}q^{2}+(-1+2\beta _{1}-\beta _{3})q^{3}+(\beta _{1}+\cdots)q^{4}+\cdots$$
65.2.e.b $4$ $0.519$ $$\Q(\sqrt{-3}, \sqrt{13})$$ None $$1$$ $$-2$$ $$-4$$ $$2$$ $$q+\beta _{1}q^{2}+(-1-\beta _{2})q^{3}+(-1+\beta _{1}+\cdots)q^{4}+\cdots$$
65.2.f.a $2$ $0.519$ $$\Q(\sqrt{-1})$$ None $$0$$ $$2$$ $$-4$$ $$-4$$ $$q+iq^{2}+(1-i)q^{3}+q^{4}+(-2-i)q^{5}+\cdots$$
65.2.f.b $8$ $0.519$ 8.0.619810816.2 None $$0$$ $$-6$$ $$-2$$ $$0$$ $$q-\beta _{6}q^{2}+(-1+\beta _{2}+\beta _{4}-\beta _{5})q^{3}+\cdots$$
65.2.k.a $2$ $0.519$ $$\Q(\sqrt{-1})$$ None $$2$$ $$2$$ $$-2$$ $$0$$ $$q+q^{2}+(1+i)q^{3}-q^{4}+(-1-2i)q^{5}+\cdots$$
65.2.k.b $8$ $0.519$ 8.0.619810816.2 None $$-4$$ $$-6$$ $$2$$ $$0$$ $$q+\beta _{5}q^{2}+(-1+\beta _{2}+\beta _{4}-\beta _{5})q^{3}+\cdots$$
65.2.l.a $8$ $0.519$ 8.0.49787136.1 None $$0$$ $$0$$ $$0$$ $$0$$ $$q+(\beta _{1}+\beta _{5})q^{2}+(\beta _{3}+\beta _{5})q^{3}+(\beta _{2}+\beta _{4}+\cdots)q^{4}+\cdots$$
65.2.m.a $8$ $0.519$ 8.0.22581504.2 None $$0$$ $$2$$ $$0$$ $$-6$$ $$q+(-1+\beta _{1}+\beta _{2}+\beta _{4}-\beta _{5})q^{2}+(\beta _{2}+\cdots)q^{3}+\cdots$$
65.2.n.a $12$ $0.519$ $$\mathbb{Q}[x]/(x^{12} - \cdots)$$ None $$0$$ $$0$$ $$-6$$ $$0$$ $$q-\beta _{4}q^{2}+(\beta _{4}-\beta _{11})q^{3}+(-\beta _{2}-\beta _{6}+\cdots)q^{4}+\cdots$$
65.2.o.a $20$ $0.519$ $$\mathbb{Q}[x]/(x^{20} + \cdots)$$ None $$-4$$ $$-2$$ $$-6$$ $$-6$$ $$q+(-\beta _{3}+\beta _{4})q^{2}+(\beta _{2}+\beta _{4}+\beta _{8}-\beta _{12}+\cdots)q^{3}+\cdots$$
65.2.t.a $20$ $0.519$ $$\mathbb{Q}[x]/(x^{20} + \cdots)$$ None $$-6$$ $$-2$$ $$0$$ $$-2$$ $$q+\beta _{1}q^{2}+(-\beta _{1}-\beta _{2}+\beta _{3}-\beta _{4}+\beta _{6}+\cdots)q^{3}+\cdots$$
65.3.g.a $24$ $1.771$ None $$0$$ $$0$$ $$-4$$ $$0$$
65.3.h.a $24$ $1.771$ None $$0$$ $$-4$$ $$0$$ $$0$$
65.3.i.a $24$ $1.771$ None $$0$$ $$-4$$ $$4$$ $$-4$$
65.3.j.a $16$ $1.771$ $$\mathbb{Q}[x]/(x^{16} - \cdots)$$ None $$0$$ $$0$$ $$0$$ $$20$$ $$q-\beta _{2}q^{2}+\beta _{6}q^{3}+(\beta _{1}-\beta _{2}+\beta _{8}+\beta _{12}+\cdots)q^{4}+\cdots$$
65.3.p.a $40$ $1.771$ None $$0$$ $$0$$ $$0$$ $$-40$$
65.3.q.a $48$ $1.771$ None $$-6$$ $$-2$$ $$-16$$ $$-2$$
65.3.r.a $48$ $1.771$ None $$-6$$ $$-2$$ $$0$$ $$-6$$
65.3.s.a $48$ $1.771$ None $$0$$ $$0$$ $$-2$$ $$0$$
65.4.a.a $1$ $3.835$ $$\Q$$ None $$5$$ $$2$$ $$-5$$ $$-12$$ $+$ $$q+5q^{2}+2q^{3}+17q^{4}-5q^{5}+10q^{6}+\cdots$$
65.4.a.b $2$ $3.835$ $$\Q(\sqrt{6})$$ None $$-2$$ $$-4$$ $$10$$ $$-20$$ $-$ $$q+(-1+\beta )q^{2}+(-2-\beta )q^{3}+(-1+\cdots)q^{4}+\cdots$$
65.4.a.c $2$ $3.835$ $$\Q(\sqrt{17})$$ None $$1$$ $$0$$ $$-10$$ $$58$$ $+$ $$q+\beta q^{2}+(-2+4\beta )q^{3}+(-4+\beta )q^{4}+\cdots$$
65.4.a.d $2$ $3.835$ $$\Q(\sqrt{3})$$ None $$4$$ $$-10$$ $$-10$$ $$-36$$ $-$ $$q+(2+\beta )q^{2}+(-5-3\beta )q^{3}+(-1+4\beta )q^{4}+\cdots$$
65.4.a.e $5$ $3.835$ $$\mathbb{Q}[x]/(x^{5} - \cdots)$$ None $$0$$ $$8$$ $$25$$ $$38$$ $+$ $$q-\beta _{1}q^{2}+(2+\beta _{1}+\beta _{3})q^{3}+(7-\beta _{2}+\cdots)q^{4}+\cdots$$
65.4.b.a $2$ $3.835$ $$\Q(\sqrt{-1})$$ None $$0$$ $$0$$ $$4$$ $$0$$ $$q+3iq^{2}-4iq^{3}-q^{4}+(2-11i)q^{5}+\cdots$$
65.4.b.b $16$ $3.835$ $$\mathbb{Q}[x]/(x^{16} + \cdots)$$ None $$0$$ $$0$$ $$-20$$ $$0$$ $$q+\beta _{2}q^{2}+\beta _{4}q^{3}+(-4+\beta _{1})q^{4}+(-1+\cdots)q^{5}+\cdots$$
65.4.c.a $14$ $3.835$ $$\mathbb{Q}[x]/(x^{14} + \cdots)$$ None $$0$$ $$0$$ $$0$$ $$0$$ $$q+\beta _{1}q^{2}-\beta _{4}q^{3}+(-4+\beta _{2})q^{4}-\beta _{7}q^{5}+\cdots$$
65.4.d.a $2$ $3.835$ $$\Q(\sqrt{-1})$$ None $$-2$$ $$0$$ $$10$$ $$48$$ $$q-q^{2}+iq^{3}-7q^{4}+(5-5i)q^{5}-iq^{6}+\cdots$$
65.4.d.b $2$ $3.835$ $$\Q(\sqrt{-1})$$ None $$2$$ $$0$$ $$-10$$ $$-48$$ $$q+q^{2}+iq^{3}-7q^{4}+(-5+5i)q^{5}+\cdots$$
65.4.d.c $16$ $3.835$ $$\mathbb{Q}[x]/(x^{16} + \cdots)$$ None $$0$$ $$0$$ $$0$$ $$0$$ $$q-\beta _{7}q^{2}-\beta _{6}q^{3}+(6+\beta _{2})q^{4}+(-\beta _{4}+\cdots)q^{5}+\cdots$$
65.4.e.a $14$ $3.835$ $$\mathbb{Q}[x]/(x^{14} - \cdots)$$ None $$-2$$ $$4$$ $$-70$$ $$-7$$ $$q-\beta _{1}q^{2}+(-\beta _{6}+\beta _{11})q^{3}+(-4-\beta _{5}+\cdots)q^{4}+\cdots$$
65.4.e.b $14$ $3.835$ $$\mathbb{Q}[x]/(x^{14} - \cdots)$$ None $$2$$ $$8$$ $$70$$ $$75$$ $$q+(-\beta _{1}+\beta _{2})q^{2}+(1+\beta _{4}-\beta _{6}-\beta _{11}+\cdots)q^{3}+\cdots$$
65.4.f.a $2$ $3.835$ $$\Q(\sqrt{-1})$$ None $$0$$ $$-10$$ $$20$$ $$-52$$ $$q+iq^{2}+(-5+5i)q^{3}+7q^{4}+(10+\cdots)q^{5}+\cdots$$
65.4.f.b $36$ $3.835$ None $$0$$ $$6$$ $$-30$$ $$48$$
65.4.k.a $2$ $3.835$ $$\Q(\sqrt{-1})$$ None $$2$$ $$-10$$ $$10$$ $$0$$ $$q+q^{2}+(-5-5i)q^{3}-7q^{4}+(5+10i)q^{5}+\cdots$$
65.4.k.b $36$ $3.835$ None $$-2$$ $$6$$ $$-26$$ $$0$$
65.4.l.a $40$ $3.835$ None $$0$$ $$0$$ $$0$$ $$0$$
65.4.m.a $28$ $3.835$ None $$0$$ $$-12$$ $$0$$ $$-36$$
65.4.n.a $36$ $3.835$ None $$0$$ $$0$$ $$10$$ $$0$$
65.4.o.a $76$ $3.835$ None $$-6$$ $$-2$$ $$10$$ $$-6$$
65.4.t.a $76$ $3.835$ None $$-6$$ $$-2$$ $$4$$ $$-2$$
65.5.g.a $52$ $6.719$ None $$0$$ $$0$$ $$58$$ $$0$$
65.5.h.a $52$ $6.719$ None $$0$$ $$-4$$ $$0$$ $$0$$ | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 1, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.943328320980072, "perplexity": 1511.1516945392477}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2023-06/segments/1674764500044.66/warc/CC-MAIN-20230203091020-20230203121020-00667.warc.gz"} |
http://theory.uwinnipeg.ca/mod_tech/node45.html | Next: Angular acceleration Up: Circular motion Previous: Angular position
## Angular velocity
In analogy with the concept of velocity for linear motion, the angular velocity for rotational motion can be defined. One first introduces the average angular velocity over a time by which the object moves from a point A on a circle to B:
The instantaneous angular velocity at a point A is then defined to be the average angular velocity between A and a point B as the point B approaches A:
Angular velocity is measured in radians / second, although for motors in particular it is commonly expressed in rpm (revolutions per minute).
Next: Angular acceleration Up: Circular motion Previous: Angular position
modtech@theory.uwinnipeg.ca
1999-09-29 | {"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9937328696250916, "perplexity": 586.4382962330985}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.3, "absolute_threshold": 10, "end_threshold": 5, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2016-30/segments/1469258948913.96/warc/CC-MAIN-20160723072908-00275-ip-10-185-27-174.ec2.internal.warc.gz"} |
http://mathoverflow.net/questions/76493/functoriality-of-adjugate-matrix | i'm interested in geometric interpretations of many linear algebra notions (check also related geometric interpretation of matrix minors). it came to me recently that geometric description of adjugate matrix (for example in case 3×3-matrix) might be quite hard—feel welcome to fill the gap!—but what catched my attention is functoriality of adjugate matrix ($\scriptstyle \mathbf I^\mathrm D = \mathbf I$ and $\scriptstyle (\mathbf{AB})^\mathrm D = \mathbf B^\mathrm D \mathbf A^\mathrm D$); my question is:
what kind of functor is the adjugating (for linear endomorphisms)?
it seems to have strong relationship with (hermitian) adjoint but has slightly different properties (it commutes with transpose). thanks in advance!
-
What does "what kind of functor" mean? – Igor Rivin Sep 27 '11 at 11:18
hmm… i know for example that matrix transpose corresponds to dualization functor or rather it is it's special case. for transpose i know that it's functorial: $I^\mathrm T = I$, $(\mathbf{AB})^\mathrm T = \mathbf B^\mathrm T \mathbf A^\mathrm T$ and it commutes with inverse. this functor is $(\cdot)^\star\colon \mathrm{Hom}(M, N) \to \mathrm{Hom}\left(N^\star, M^\star\right)$ for $R$-modules $M$ and $N$, where $M^\star, N^\star$ are their dual modules respectively, and $\mathrm{Hom}(M, N)$ denotes set of all homomorphisms $M \to N$. i'm looking for similar explanation! :p – joel Sep 27 '11 at 13:09
i found quite a satisfying answer to this question which gives enough trails for further enquiry. the answer involves exterior algebra and gradation (check also hodge duality).
if $\mathrm A\colon V \to V$ is a linear map, then it naturally induces a graded operator $\mathrm A^*$ in the exterior algebra of $V$. when $V$ has finite dimension, there are two pieces of the exterior algebra which are isomorphic to $V$, namely $\Lambda^1(V)$, the dual space of $V$, and $\Lambda^{n-1}(V)$, being the space of $(n-1)$-multivectors of $V$.
the restriction of $\mathrm A^*$ to $\Lambda^1(V)$ is the dual map (also called adjoint map). generally the dual space is not canonically isomorphic to $V$ if it has only linear structure; this changes when some sort of duality is established thanks to an extra structure, e.g. inner product. this is the adjoint linear map acting in $V$ with matrix $\mathbf A^\mathrm T$ depending on the choice of basis. on the other hand $\Lambda^{n-1}(V)$ is naturally isomorphic to $V$ (the isomorphism is given by the determinant), and so the restriction of $\mathrm A^*$ to $\Lambda^{n-1}(V)$ naturally induces an linear map on $V$ denoted $\operatorname{adj} \mathrm A$ with matrix $\mathbf A^\mathrm D$. since this is natural, an matrix adjugate can be defined in terms of this.
both notions of adjointness (classical and conjugate transpose) are quite related. the simple one is just duality and makes more sense for operators in general vector spaces (or better in inner product space). the seemingly not-so-simple one is natural, makes sense for operators or matrices, is usually expressed in terms of matrices, and appears often in relation to quadratic forms.
source: google groups on sage developement
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Well, if your matrix happens to be invertible, the adjugate is the inverse. Otherwise, the adjugate gives the action on the $n-1$st exterior power (you can use the $*$ operator to map it back to the space itself. @Qiaochu has alluded to this in his answer to the question you cite. You can also check out Section 9 of my paper http://arxiv.org/pdf/math/0403375v1 to see some other geometric results on the subjects (the published version has fewer typos, so you might want to look at that too, if you have access).
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If the matrix is invertible, I think the adjugate would actually be the inverse times the determinant. Right? – Manny Reyes Sep 27 '11 at 13:39
i'll check it out right away—if it's possible would you be kind enough to explain in plain language (basic linear algebra if it's possible) how does action of exterior power works? :) thanks in advance for your effort! – joel Sep 27 '11 at 13:55
@Manny: yes, that's correct. – Igor Rivin Sep 27 '11 at 13:56
@Manny-Reyes: i know that $\mathbf{AA}^\mathrm D = \mathbf A^\mathrm D \mathbf A = (\det \mathbf A) \mathbf I$ which gives our result if $\mathbf A$ is invertible, because then $\mathbf{AA}^{-1} = \mathbf A^{-1} \mathbf A = \mathbf I$. – joel Sep 27 '11 at 13:57 | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9265288710594177, "perplexity": 312.43815351869625}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2015-27/segments/1435375095677.90/warc/CC-MAIN-20150627031815-00234-ip-10-179-60-89.ec2.internal.warc.gz"} |
https://www.shaalaa.com/question-bank-papers/maharashtra-state-board-ssc-hsc-9th-10th-ssc-geometry-mathematics-2-10th-board-exam-2014_6195 | # Question Paper - Geometry 2014 - 2015-S.S.C-Board Exam Maharashtra State Board (MSBSHSE)
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SubjectGeometry
Year2014 - 2015 (March)
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Marks: 40
Q: 1 | Solve any five sub-questions :[5]
Q: 1.1[1]
In the following figure seg AB ⊥ seg BC, seg DC ⊥ seg BC. If AB = 2 and DC = 3, find (A(triangleABC))/(A(triangleDCB))
view question and solution
Q: 1.2[1]
Find the slope and y-intercept of the line y = -2x + 3.
view question and solution
Q: 1.3[1]
Q: 1.4[1]
Q: 1.5[1]
The volume of a cube is 1000 cm3. Find the side of a cube.
view question and solution
Q: 1.6[1]
If two circles with radii 5 cm and 3 cm respectively touch internally, find the distance between their centres.
view question and solution
Q: 2 | Solve any four sub-questions :[8]
Q: 2.1[2]
Q: 2.2[2]
Draw ∠ABC of measure 105° and bisect it.
view question and solution
Q: 2.3[2]
Find the slope of the line passing through the points A(-2, 1) and B(0, 3).
view question and solution
Q: 2.4[2]
Find the area of the sector whose arc length and radius are 8 cm and 3 cm respectively.
view question and solution
Q: 2.5[2]
Q: 2.6[2]
Q: 3 | Solve any three sub-questions :[9]
Q: 3.1[3]
In the following figure, Q is the centre of a circle and PM, PN are tangent segments to the circle. If ∠MPN = 50°, find ∠MQN.
view question and solution
Q: 3.2[3]
Draw the tangents to the circle from the point L with radius 2.7 cm. Point ‘L’ is at a distance 6.9 cm from the centre ‘M’.
view question and solution
Q: 3.3[3]
The ratio of the areas of two triangles with the common base is 14 : 9. Height of the larger triangle is 7 cm, then find the corresponding height of the smaller triangle.
view question and solution
Q: 3.4[3]
Two building are in front of each other on either side of a road of width 10 metres. From the top of the first building which is 40 metres high, the angle of elevation to the top of the second is 45°. What is the height of the second building?
view question and solution
Q: 3.5[3]
Find the volume and surface area of a sphere of radius 2.1 cm.
(pi=22/7)
view question and solution
Q: 4[8]
Q: 4.1[4]
Prove that ‘the opposite angles of a cyclic quadrilateral are supplementary’.
view question and solution
Q: 4.2[4]
Prove that sin6θ + cos6θ = 1 – 3 sin2θ. cos2θ.
view question and solution
Q: 4.3[4]
A test tube has diameter 20 mm and height is 15 cm. The lower portion is a hemisphere. Find the capacity of the test tube. (π = 3.14)
view question and solution
Q: 5 | Solve any two sub-questions :[10]
Q: 5.1[5]
Prove that the angle bisector of a triangle divides the side opposite to the angle in the ratio of the remaining sides.
view question and solution
Q: 5.2[5]
Write down the equation of a line whose slope is 3/2 and which passes through point P, where P divides the line segment AB joining A(-2, 6) and B(3, -4) in the ratio 2 : 3.
view question and solution
Q: 5.3[5]
ΔRST ~ ΔUAY, In ΔRST, RS = 6 cm, ∠S = 50°, ST = 7.5 cm. The corresponding sides of ΔRST and ΔUAY are in the ratio 5 : 4. Construct ΔUAY.
view question and solution
S | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.7477383017539978, "perplexity": 1859.8734239840503}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2017-39/segments/1505818687938.15/warc/CC-MAIN-20170921224617-20170922004617-00208.warc.gz"} |
https://www.investopedia.com/terms/r/retentionratio.asp | ## What Is the Retention Ratio?
The retention ratio is the proportion of earnings kept back in the business as retained earnings. The retention ratio refers to the percentage of net income that is retained to grow the business, rather than being paid out as dividends. It is the opposite of the payout ratio, which measures the percentage of profit paid out to shareholders as dividends. The retention ratio is also called the plowback ratio.
1:50
## The Formulas for the Retention Ratio Are
\begin{aligned} \text{Retention Ratio}=\frac{\text{Retained Earnings}}{\text{Net Income}} \end{aligned}
or the alternative formula:
\begin{aligned} \text{Retention Ratio}=\frac{\text{Net Income} -\text{ Dividends Distributed}}{\text{Net Income}}\\ \end{aligned}
## How to Calculate the Retention Ratio
1. There are two ways to calculate the retention ratio. The first formula involves locating retained earnings in the shareholders' equity section of the balance sheet.
2. Obtain the company's net income figure listed at the bottom of its income statement.
3. Divide the company's retained earnings by the net income figure.
4. The alternative formula does not use retained earnings but instead subtracts dividends distributed from net income and divides the result by net income.
## What Does the Retention Ratio Tell You?
Companies that make a profit at the end of a fiscal period can use the funds for a number of purposes. The company's management can pay the profit to shareholders as dividends, they can retain it to reinvest in the business for growth, or they can do some combination of both. The portion of the profit that a company chooses to retain or save for later use is called retained earnings.
Retained earnings (RE) is the amount of net income left over for the business after it has paid out dividends to its shareholders. A business generates earnings that can be positive (profits) or negative (losses).
Retained earnings are similar to a savings account because it's the cumulative collection of profit that's retained or not paid out to shareholders. Profit can also be re-invested back into the company for growth purposes.
The retention ratio helps investors determine how much money a company is keeping to reinvest in the company's operation. If a company pays all of its retained earnings out as dividends or does not reinvest back into the business, earnings growth might suffer. Also, a company that is not using its retained earnings effectively have an increased likelihood of taking on additional debt or issuing new equity shares to finance growth.
As a result, the retention ratio helps investors determine a company's reinvestment rate. However, companies that hoard too much profit might not be using their cash effectively and might be better off had the money been invested in new equipment, technology, or expanding product lines. New companies typically don't pay dividends since they're still growing and need the capital to finance growth. However, established companies usually pay a portion of their retained earnings out as dividends while also reinvesting a portion back into the company.
The retention ratio is typically higher for growth companies that are experiencing rapid increases in revenues and profits. A growth company would prefer to plow earnings back into its business if it believes that it can reward its shareholders by increasing revenues and profits at a faster pace than shareholders could achieve by investing their dividend receipts.
Investors may be willing to forego dividends if a company has high growth prospects, which is typically the case with companies in sectors such as technology and biotechnology. The retention rate for technology companies in a relatively early stage of development is generally 100%, as they seldom pay dividends. But in mature sectors such as utilities and telecommunications, where investors expect a reasonable dividend, the retention ratio is typically quite low because of the high dividend payout ratio.
The retention ratio may change from one year to the next, depending on the company’s earnings volatility and dividend payment policy. Many blue-chip companies have a policy of paying steadily increasing or, at least, stable dividends. Companies in defensive sectors such as pharmaceuticals and consumer staples are likely to have more stable payout and retention ratios than energy and commodity companies, whose earnings are more cyclical.
## Real-World Example of the Retention Ratio
Below is a copy of the balance sheet for Facebook Inc. (FB) as reported in the company's annual 10-K, which was filed on January 31, 2019.
• In the shareholders' equity section, Facebook's retained earnings totaled $41.981 billion for the period (highlighted in green). • From the company's income statement, not shown, Facebook posted a profit or net income of$22.112 billion for the same period.
• We calculate Facebook's retention ratio by the following: $41.981 billion /$22.112 billion, which equals 1.89 or 189%.
The reason the retention ratio is so high is that Facebook has accumulated profit and didn't pay dividends. As a result, the company had plenty of retained earnings to invest in the company's future. A high retention ratio is very common for technology companies.
## The Difference Between Retention Ratio and Dividend Payout Ratio
The dividend payout ratio is the ratio of the total amount of dividends paid out to shareholders relative to the net income of the company. It is the percentage of earnings paid to shareholders in dividends. The amount that is not paid to shareholders is retained by the company to pay off debt or to reinvest in core operations.
The dividend payout ratio is the percentage of profit or net income that's paid out to shareholders while conversely, the retention ratio is the percentage of profit retained or not paid out to shareholders as dividends.
## Limitations of Using the Retention Ratio
A limitation of the retention ratio is that companies that have a significant amount of retained earnings will likely have a high retention ratio, but that doesn't necessarily mean the company is investing those funds back into the company.
Also, a retention ratio doesn't calculate how the funds are invested or if any investment back into the company was done effectively. It's best to utilize the retention ratio along with other financial metrics to determine how well a company is deploying its retained earnings into investments.
As with any financial metric or ratio, it's also important to compare the results with companies in the same industry as well as monitor the ratio over several quarters to determine if there's any trend. | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 2, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.3584836423397064, "perplexity": 3148.746934455982}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2020-05/segments/1579250591234.15/warc/CC-MAIN-20200117205732-20200117233732-00426.warc.gz"} |
https://leconjugueur.lefigaro.fr/conjugaison/anglais/shall+drop.html | Verbe anglais à conjuguer : Modal : aucun | may | might | can | could | shall | should | will | would | must | ought to
# Conjugaison du verbe anglais SHALL DROP
Verbe régulier : drop - dropped - dropped
Traduction française : laisser tomber jeter
## Affirmation
Forme simple
I shall drop
you shall drop
he shall drop
we shall drop
you shall drop
they shall drop
Forme en V-ing
I shall be dropping
you shall be dropping
he shall be dropping
we shall be dropping
you shall be dropping
they shall be dropping
Perfect
I shall have dropped
you shall have dropped
he shall have dropped
we shall have dropped
you shall have dropped
they shall have dropped
Perfect en V-ing
I shall have been dropping
you shall have been dropping
he shall have been dropping
we shall have been dropping
you shall have been dropping
they shall have been dropping
## Négation
Forme simple
I shall not drop
you shall not drop
he shall not drop
we shall not drop
you shall not drop
they shall not drop
Forme en V-ing
I shall not be dropping
you shall not be dropping
he shall not be dropping
we shall not be dropping
you shall not be dropping
they shall not be dropping
Perfect
I shall not have dropped
you shall not have dropped
he shall not have dropped
we shall not have dropped
you shall not have dropped
they shall not have dropped
Perfect en V-ing
I shall not have been dropping
you shall not have been dropping
he shall not have been dropping
we shall not have been dropping
you shall not have been dropping
they shall not have been dropping
## Interrogation
Forme simple
shall I drop?
shall you drop?
shall he drop?
shall we drop?
shall you drop?
shall they drop?
Forme en V-ing
shall I be dropping?
shall you be dropping?
shall he be dropping?
shall we be dropping?
shall you be dropping?
shall they be dropping?
Perfect
shall I have dropped?
shall you have dropped?
shall he have dropped?
shall we have dropped?
shall you have dropped?
shall they have dropped?
Perfect en V-ing
shall I have been dropping?
shall you have been dropping?
shall he have been dropping?
shall we have been dropping?
shall you have been dropping?
shall they have been dropping?
## Interro-négation
Forme simple
shall I not drop?
shall you not drop?
shall he not drop?
shall we not drop?
shall you not drop?
shall they not drop?
Forme en V-ing
shall I not be dropping?
shall you not be dropping?
shall he not be dropping?
shall we not be dropping?
shall you not be dropping?
shall they not be dropping?
Perfect
shall I not have dropped?
shall you not have dropped?
shall he not have dropped?
shall we not have dropped?
shall you not have dropped?
shall they not have dropped?
Perfect en V-ing
shall I not have been dropping?
shall you not have been dropping?
shall he not have been dropping?
shall we not have been dropping?
shall you not have been dropping?
shall they not have been dropping? | {"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9958847165107727, "perplexity": 29964.738247142028}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.3, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2019-47/segments/1573496671053.31/warc/CC-MAIN-20191121231600-20191122015600-00480.warc.gz"} |
https://www.open-systems-pharmacology.org/OSPSuite-R/articles/create-run-population.html | ## Population simulations
Population simulations can be easily performed in R by combining the simulation loaded from a *.pkml file with the population information created in PK-Sim and exported to CSV format (for details, please refer to OSPS online documentation) or created directly in R (see Creating populations).
The method loadPopulation creates an object of the Population class that can be passed to the runSimulation() method (see Running simulations and retrieving the results).
library(ospsuite)
#> Loaded Common Language Runtime version 4.0.30319.42000
# Load population information from csv
popFilePath <- system.file("extdata", "pop.csv", package = "ospsuite")
print(myPopulation)
#> Population:
#> Number of Individuals: 10
## Creating populations
Similar to creating individual parameter sets (see Creating individuals), a population is created from population characteristics created by calling the method createPopulationCharacteristics(). To see the list of available values for the arguments species and population (only for human), use the enums Species and HumanPopulation, respectively. The returned object of type PopulationCharacteristics is then passed to the function createPopulation to generate a set of parameter values. The algorithm behind is the same used in PK-Sim when creating an population. Molecule ontogenies can be added as described in the vignette Creating individuals.
library(ospsuite)
# If no unit is specified, the default units are used. For "height" it is "dm", for "weight" it is "kg", for "age" it is "year(s)".
populationCharacteristics <- createPopulationCharacteristics(
species = Species$Human, population = HumanPopulation$Asian_Tanaka_1996,
numberOfIndividuals = 50,
proportionOfFemales = 50,
weightMin = 30,
weightMax = 98,
weightUnit = "kg",
heightMin = NULL,
heightMax = NULL,
ageMin = 0,
ageMax = 80,
ageUnit = "year(s)"
)
#> Error in rClr::clrLoadAssembly(pksimR): Failure in rclr_ms_call_static_method, but could not retrieve an error message
print(populationCharacteristics)
# Create population from population characteristics
result <- createPopulation(populationCharacteristics = populationCharacteristics)
myPopulation <- result$population #> Error in eval(expr, envir, enclos): object 'result' not found print(myPopulation) #> Population: #> Number of Individuals: 10 ## Running population simulation To run a population simulation, the Population object created by the createPopulation method must be passed to the runSimulation() method: library(ospsuite) # Load simulation simFilePath <- system.file("extdata", "Aciclovir.pkml", package = "ospsuite") sim <- loadSimulation(simFilePath) # Run population simulation simulationResults <- runSimulation(simulation = sim, population = myPopulation) print(simulationResults) #> SimulationResults: #> Number of individuals: 10 Population simulations are run in parallel on multi-core machines - one core simulates a subset of all individuals defined in the population. By default, the number of cores used equals the maximal number of logical cores available minus one. The user can change the default behavior by providing custom SimulationRunOptions(). # Load simulation simFilePath <- system.file("extdata", "Aciclovir.pkml", package = "ospsuite") sim <- loadSimulation(simFilePath) # Create a SimulationRunOptions object simRunOptions <- SimulationRunOptions$new()
print(simRunOptions)
#> SimulationRunOptions:
#> numberOfCores: 15
#> checkForNegativeValues: TRUE
#> showProgress: FALSE
# Change the maximal number of cores to use and show a progress bar during simulation
simRunOptions$numberOfCores <- 3 simRunOptions$showProgress <- TRUE
# Run population simulation with custom options
populationResults <- runSimulation(simulation = sim, population = myPopulation, simulationRunOptions = simRunOptions)
print(populationResults)
#> SimulationResults:
#> Number of individuals: 10
Simulated time-value pairs for a specific output from the SimulationResults-object returned by the runSimulation method can be accessed with the method getOutputValues. The user can provide either the path(s) of the output (which can be a molecule, a parameter, or an observer), or the object(s) of the type Molecule, Parameter, or Quantity (for observers) with the argument quantitiesOrPaths. If no output is specified, all outputs available in the simulation results are returned.
The paths of all available outputs can be accessed via
populationResults$allQuantityPaths #> [1] "Organism|PeripheralVenousBlood|Aciclovir|Plasma (Peripheral Venous Blood)" getOutputValues() returns a list with two entries: data and metadata: • data is a dataframe with two predefined columns (IndividualId and Time) as well as one column for each requested output • IndividualId • Time a vector with simulated time values (in minutes, equal for all outputs) • a vector with simulated entries for each output requested. The values of IndividualId, Time, and the simulated outputs, are appended for each simulated individual. Note that this results in non-monotonously increasing column Time. # Get simulated results by path resultsPath <- populationResults$allQuantityPaths[[1]]
print(resultsPath)
#> [1] "Organism|PeripheralVenousBlood|Aciclovir|Plasma (Peripheral Venous Blood)"
resultsData <- getOutputValues(populationResults, quantitiesOrPaths = resultsPath)
resultsTime <- resultsData$data$Time
resultsValues <- resultsData$data$Organism|PeripheralVenousBlood|Aciclovir|Plasma (Peripheral Venous Blood)
plot(resultsTime, resultsValues, type = "l")
To get the results for a specific individual or a set of individuals, the argument individualIds of the method getOutputValues() can be specified:
# Get simulated results by path
resultsPath <- populationResults$allQuantityPaths[[1]] print(resultsPath) #> [1] "Organism|PeripheralVenousBlood|Aciclovir|Plasma (Peripheral Venous Blood)" # Get only the results for individuals with IDs 1 and 2 resultsData <- getOutputValues(populationResults, quantitiesOrPaths = resultsPath, individualIds = c(1, 2)) resultsTime <- resultsData$data$Time resultsValues <- resultsData$data\$Organism|PeripheralVenousBlood|Aciclovir|Plasma (Peripheral Venous Blood)
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https://www.emerald.com/insight/content/doi/10.1108/IJIF-02-2018-0019/full/html | # Proposed models for unit trust waqf and the parameters for their application
Syahnaz Sulaiman (Faculty of Economics and Muamalat, Universiti Sains Islam Malaysia, Nilai, Malaysia)
Aznan Hasan (Institute of Islamic Banking and Finance (IIiBF), International Islamic University Malaysia, Kuala Lumpur, Malaysia)
Azman Mohd Noor (Institute of Islamic Banking and Finance (IIiBF), International Islamic University Malaysia, Kuala Lumpur, Malaysia)
Muhd Issyam Ismail (Institute of Islamic Banking and Finance (IIiBF), International Islamic University Malaysia, Kuala Lumpur, Malaysia)
Nazrul Hazizi Noordin (International Centre for Education in Islamic Finance, Kuala Lumpur, Malaysia)
ISSN: 2289-4365
Article publication date: 26 June 2019
Issue publication date: 26 June 2019
6204
## Abstract
### Purpose
This paper aims to present the viability of unit trust waqf (Islamic endowment) as an alternative asset class for waqf creation.
### Design/methodology/approach
This paper starts with the conceptual exploration of the literature in the areas of waqf. The sources of the literature cover authentic sources of the Qurʾān and ḥadīth, as well as secondary sources such as books, journal articles and online resources.
### Findings
This paper provides the conceptual framework of five models of unit trust waqf and their investment management parameters.
### Originality/value
The novelty of this paper lies in its attempt to highlight the importance of waqf investment strategy in ensuring sustainable returns for waqf. It does so by introducing the conceptual models of unit trust waqf as viable mechanisms to pool more cash waqf from individual investors. The sustainability of the capital waqf assets in the form of unit trusts is maintained through the parameters for its application proposed towards the end of the paper.
## Citation
Sulaiman, S., Hasan, A., Mohd Noor, A., Ismail, M.I. and Noordin, N.H. (2019), "Proposed models for unit trust waqf and the parameters for their application", ISRA International Journal of Islamic Finance, Vol. 11 No. 1, pp. 62-81. https://doi.org/10.1108/IJIF-02-2018-0019
## Publisher
:
Emerald Publishing Limited
Copyright © 2019, Syahnaz Sulaiman, Aznan Hasan, Azman Mohd Noor, Muhd Issyam Ismail and Nazrul Hazizi Noordin.
Published in ISRA International Journal of Islamic Finance. Published by Emerald Publishing Limited. This article is published under the Creative Commons Attribution (CC BY 4.0) licence. Anyone may reproduce, distribute, translate and create derivative works of this article (for both commercial and non-commercial purposes), subject to full attribution to the original publication and authors. The full terms of this licence may be seen at http://creativecommons.org/licences/by/4.0/legalcode
## Introduction
The institution of waqf is one of the socio-economic institutions in Islam that encourages Muslims to be creative and innovative in generating revenues and providing various goods and services for Muslim societies (Abdel Mohsin, 2013). Waqf institutions are facing the paradox of having huge numbers of waqf properties, yet many are left idle and unproductive, despite the properties being located in prime areas (Ismail, 2012). This issue has sparked the attention of waqf managers and policymakers as well as Islamic financial institutions of the need to transform unproductive waqf assets into high quality and income-producing properties. The recent call for waqf revival, as well as the renewed public attention and awareness of it, is indeed crucial factors for the rapid advancement of the Islamic philanthropy sector.
There are a number of waqf stakeholder organizations in Malaysia. These include the federal agencies such as:
• JAKIM (Jaabtan Kemajuan Islam Malaysia or Department of Islamic Development Malaysia);
• JAWHAR (Jabatan Wakaf, Zakat dan Haji or the Department of Waqf, Zakat and Hajj) under the Prime Minister Department of Malaysia; and
• Yayasan Waqaf Malaysia (Waqf Foundation of Malaysia).
Equally (or possibly more) important are the State Islamic Religious Councils (Majlis Agama Islam Negeri or SIRC). These agencies have been instrumental in organizing and promoting various programs and research activities to further develop the institution of waqf and to harness its potential for the benefit of the ummah (Muslim nation). Despite these commendable efforts, it has been reported that many waqf lands and buildings in Malaysia are not well managed or are even abandoned. As a result, the institution of waqf in Malaysia remains underdeveloped (Ismail, 2012).
One contributing factor to this problem is that the vast majority of waqf assets in Malaysia comprise immovable properties of low liquidity (Mohsin and Mohammad, 2011). For instance, in 2004 in Selangor alone, real estate waqf accounted for 97 per cent of waqf assets; only 3 per cent were in cash (Yang, 2014). This situation is a stark contrast to other countries such as Singapore (a Muslim-minority country) and Kuwait (a Muslim-majority country) where, respectively, 13 per cent and 41 per cent of their waqf assets are in cash deposits and other capital instruments. In fact, the pool of fixed waqf assets in Malaysia is much higher than some reputable endowments in Europe such as Harvard University (25 per cent of their endowments are in real assets) (Harvard University, 2013) and Yale University (28 per cent of their endowments are in real assets) (Yale University, 2013).
Other than that, the prospective of the waqf institution as a source of wealth creation is also potentially hindered by numerous issues. One of them is the lack of funds faced by mutawallīs (waqf managers) (Mahamood, 2006a, 2006b; Mohd Salleh and Muḥammad, 2008; Ahmad and Muhamed, 2011; Sulaiman, 2012). This is because sufficient funds, particularly in the form of highly liquid waqf assets, are desperately needed by the mutawallīs to enable them to manage the waqf assets towards realizing the waqf’s ultimate objective of serving the needs of the ummah (Zarqa, 1994). This “asset-rich, cash-poor” syndrome that has been suffered by many waqf establishments in Malaysia (Abdul Karim, 2011) is indeed serious. According to a report published by Yayasan Waqaf Malaysia (2016), only 11.4 per cent of the total 31,000 hectares of waqf lands throughout the country in 2016 have been developed; the remainder is sitting idle.
Therefore, the prospect of investing waqf assets in highly liquid financial instruments must be explored by the stakeholders; in fact, it should be given utmost priority. Up to this point, the number of waqf investments and Sharīʿah-compliant products available in the capital market are still limited. Most of the time, waqf managers are left with no choice but to keep the waqf proceeds in Islamic fixed deposits. It is thus timely for this alternative option to be given full consideration, particularly as commercial Islamic financial institutions have shown interest in being involved in the national waqf development agenda.
As such, this paper attempts to explore the viability of integrating waqf with Islamic unit trust, a modern financial instrument that is not only Sharīʿah compliant but also carries high potential for competitive returns while at the same time preserving the initial capital. Through this instrument, the current waqf asset portfolios could be diversified instead of being concentrated or frozen in non-flexible instruments and assets. Notwithstanding the exciting prospects offered by Islamic unit trust funds, the practice of unit trust waqf is still at the inception stage, calling for more in-depth studies to explore its practicality from the legal and Sharīʿah perspectives.
The rest of this paper is structured as follows. The second section explores the literature pertaining to the concept of waqf and its related issues. These include, among others, its role in the sustainability and well-being of the ummah, how it should be managed and governance issues. The discussion also deals with Sharīʿah rulings on unit trust waqf, which hinge upon the permissibility of cash waqf and temporary waqf. It further deals with the recent development of the unit trust industry in Malaysia and sustainable waqf investment strategies. The section thereafter proposes the models of unit trust waqf. The study then explains the parameters for application of unit trust waqf, particularly in addressing several important issues such as istibdāl (substitution) and risk management strategy. The paper ends with the conclusion.
## Literature review
### Concept of waqf
According to Ibn Qudāmah (1998), waqf means “withholding the corpus of an asset [without disposing of it] and distributing its return”. Under the principle of qurbah (piety), waqf is the act of endowing one’s property for charitable purposes to get rewards from Allah (SWT) in the hereafter (Kahf, 2003). Apart from the relationship between human beings and their Creator, waqf also relates to people’s affairs among themselves in the spirit of love, brotherhood and cooperation (Sulaiman, 2008). According to Nadwi (2015), the institution of waqf primarily serves two objectives. First, in spiritual terms, waqf provides a vehicle for a perpetual reward for the donor. Second, it confers numerous socio-economic benefits to the community in general, particularly to the underprivileged. Therefore, waqf, which is referred to as ṣadaqah jāriyah (ongoing charity) in a ḥadīth (Muslim, 1998), is more attractive to Muslims, as it provides them perpetual rewards in the afterlife as compared to conventional endowment where the benefits are only obtained in this world. The perpetual or continuous feature of waqf is further manifested through a progressive approach in developing waqf property. No waqf asset should be left idle; it must be attended to to ensure sustainable returns to the beneficiaries (Hasan and Sulaiman, 2016) in addition to its survival. Likewise, Kahf (1999) asserted that the recurring benefits generated from waqf can be used as a mechanism to increase the standard of living of the ummah and reduce poverty and difficulties among the poor and needy.
### Waqf for sustainability and well-being of the ummah
Waqf has been contributing towards the promotion of well-being and social development of nations since its inception. It particularly flourished during the golden age of Islam. It was once recognized as one of the world’s most influential third-sector institutions (Sadeq, 2002; Arshad and Haneef, 2015). The historian Hodgson (1974) characterized it as “a vehicle for financing Islam as a society”. Waqf serves as an important and effective tool for raising adequate capital to be channelled to fund various economic and social activities in a sustainable manner. In fact, a similar concept to waqf was adopted in Europe with the establishment of world-famous educational endowments such as Merton College, University of Oxford (Arjomand, 1998). Waqf’s success not only inspired the formation of today’s modern not-for-profit organizations and non-governmental organizations (NGOs) but also has left some influence in the determination of their organizational objectives.
Waqf is argued to have a broader spectrum of social and economic development than other philanthropic and redistributive instruments such as zakat (almsgiving), ṣadaqah (charity) and hibah (gift), which are mainly involved in helping the poor and needy only. The use and purpose of waqf cover:
It thus serves to fulfil a broad spectrum of societal needs (Mohammed Noor et al., 2014).
One of the significant features of waqf is that it provides flexibility of fund utilization as compared to zakat. Zakat funds must be used for specific categories of recipients. On the contrary, waqf funds can be used to provide a wide range of welfare services for both Muslims and non-Muslims. Waqf beneficiaries can also be extended to other living beings in fulfilling specific initiatives such as animal protection and environmental conservation. It can also reduce the cost to government of fulfilling public needs such as building and maintaining public infrastructure (Çizakça, 1998; Abdel Mohsin, 2013).
Another focus of discussion on the contemporary application of waqf concerns the sustainability of waqf institutions. Dafterdar (2011) argued that sustainability of waqf is an added bonus or a complement to the profitability generated by waqf. This is because the surplus generated from profit-making activities can be used to sustain the provision of social services. Sole reliance on cash donations for waqf – while not hedging against the decline of purchasing power of money received – could increase the exposure of waqf institutions to the risk of closure. Mohsin et al. (2016) opined that the preservation of benefits for the intended beneficiaries can be attained through prudent and efficient investment and development of waqf assets. Meanwhile, Sulaiman and Zakari (2015) emphasized the importance of diversifying the sources of income for waqf institutions alongside the important role played by investment managers in safeguarding the value of the waqf investment funds over time. In fact, diversification of waqf sources by venturing out into the contemporary forms of wealth like cash and shares could increase the flexibility of waqf and public participation in it. For instance, this can be done through investing waqf proceeds in the less volatile and balanced unit trust portfolios, whose underlying assets are mostly fixed income and stable asset classes such as ṣukūk and money market instruments.
This paper further presents how waqf as a social finance vehicle can contribute as a complementary alternative to governments and private-sector financial institutions which cannot undertake many socially desirable projects because of lack of funds or commercial non-viability.
### Waqf management and governance
Traditionally, the waqf institution has been considered similar to a non-profit trust (Çizakça, 2014). In regard to the administration and governance of waqf in contemporary times, many scholars emphasize the importance of professional management and transparent administration of waqf to ensure its effective outcomes. Alpay and Haneef (2015) accentuate that the transparency and accountability of the funding as well as the implementing agencies are crucial for waqf to achieve its ultimate goal of poverty reduction. In the same line of thought, Hassan and Shahid (2010) argue that professional business management would improve the institutional quality, service delivery and effective delegation of the responsibilities, thus facilitating accountability of the waqf management.
Hence, a sound corporate structure is important in ensuring that the waqf is managed professionally and able to operate in perpetuity. Sulaiman and Abdul Manaf (2009) argue that transparency is vital not only in the operation of the management of waqf but also in its reporting, as it reduces the discrepancy between the donors and the waqf administration. Thus, under the management of, for instance, a professional fund manager, waqf management would have better accountability and transparency towards adding value and promoting wealth (Mohd Ramli and Jalil, 2014).
### Definition of unit trust and the recent development of unit trust waqf applications
An Islamic unit trust fund (also known as an Islamic mutual fund) is a type of collective investment scheme that offers investors the opportunity to invest in a diversified portfolio of Sharīʿah-compliant securities, ṣukūk, money market instruments, real estate or commodities. This type of fund is determined by the assets or constituents of the portfolio. They determine its risk and the kind of investors the fund is targeting. Fundamentally, there are three varieties of unit trust funds: Islamic equity funds (which deal in shares), ṣukūk funds (fixed income funds which are relatively more stable) and money market funds (Securities Commission Malaysia, 2019). An Islamic unit trust fund is managed by professional fund managers who invest the money that is collected in a diversified portfolio of Sharīʿah-compliant financial instruments, depending upon the objective of the fund. Investors can earn income from the investment in an Islamic unit trust fund through capital gains and/or distribution of income.
In Malaysia, the market capitalization of Islamic unit trusts has shown a significant improvement over the past several years. The net asset value of Islamic unit trust funds has posted tremendous growth since the financial crisis. It went from US$5.27bn in 2009 to US$21.3bn as at January 2019 (Securities Commission Malaysia, 2019). The recent statistics provided by the Securities Commission Malaysia (SC) also show an increased number of Sharīʿah-compliant funds from only 17 out of a total of 127 funds in 2000 to 229 out of total 666 funds in 2019. This was paralleled by a tripling in the number of management companies from 13 companies in 1992 to 39 companies as at January 2019. The huge size of Islamic unit trust funds in Malaysia, which is estimated at US$21.3bn (Securities Commission Malaysia, 2019), presents a significant opportunity to create a viable and sustainable Islamic social financing source through a unit trust waqf framework. The proposed mechanics of this new type of waqf would provide an avenue for unit trust investors or unitholders to endow a portion of the units or the dividends. The concept of waqf for mutual funds or unit trusts is not new. In 2004, Dompet-Dhuafa Batasa Syariah Waqf Fund was first introduced in Indonesia on fixed-income basis. Up to 80 per cent of the fund was allocated in ṣukūk and the rest in the Islamic money market (Islamic deposits). The return rate of the fund was between 11 and 13 per cent, and part of the dividend was channelled to waqf (Siswantoro and Dewi, 2011). Unfortunately, the fund was terminated and converted to a hajj fund in 2006 due to lack of participation by investors. In addition, the fund was deemed to be ambiguous, relatively small in size with very little promotion, as well as laden with some market risk issues (Siswantoro, 2017, personal communication, 31 April). Ten years later, Dompet Dhuafa, a well-known waqf institution in Indonesia, in collaboration with BNI Asset Management, established a Sharīʿah-compliant mutual fund with a special waqf feature. This new fund of BNI-AM Dana Dompet Dhuafa, which was actually a rebranding of the previous Batasa Syariah Fund, provided an avenue for unitholders to endow some of the dividends for waqf purposes. As the fund manager, BNI Asset Management not only attracted more investors but also managed to allocate one-third of the management fees to a waqf fund (HS Dalimunthe, 2017, personal communication, 1 May). In terms of fund allocation, about 98 per cent was allocated in corporate ṣukūk, while the remaining 2 per cent was invested in Sharīʿah-compliant deposits. To spur a similar initiative of unit trust waqf in Malaysia, this drive could probably be initiated by Permodalan Nasional Berhad (PNB), a government-linked fund manager. As on 30 November 2018, PNB’s current assets under management (AUM) were recorded at US$72.1bn (Permodalan Nasional Berhad, 2018). PNB’s resilient financial performance through the Sharīʿah-compliant unit trusts, Amanah Saham Nasional (ASN) and Amanah Saham Bumiputera (ASB), have demonstrated a large potential to have the unit holders to put aside a portion of the units or dividends for waqf. ASB and ASN funds, which are guaranteed by the Malaysian Government, have been pronounced Sharīʿah compliant by the National Fatwa Committee along with many State Fatwa Committees, namely, Wilayah Persekutuan Kuala Lumpur, Selangor, Penang, Terengganu, Kelantan and Negeri Sembilan. A unit trust waqf could potentially be a viable model as waqf can be created at a minimal cost, thus giving everyone the opportunity to create waqf. Therefore, in this context, waqf can be explored as a source of funding by waqf institutions and fund managers, due to its potential as a perpetual pool of funds for their social programs.
### The legitimacy of cash waqf and other financial assets including unit trust
The majority of Muslim jurists consider cash waqf to be legitimate. From the Ḥanafī School, a disciple of Abu Hanifah, Imam Zufar approved all movable properties to be dedicated as waqf. He included the waqf of dirhams and dinars (cash waqf) as the capital in business dealings based on muḍārabah, the return of which can be directed to the charitable purposes of the waqf (Al-Tarābulsī, 1902; Ibn al-Humām, 1988; Ibn ʿĀbidīn, 2003). In addition, both Imam Muḥammad al-Shaybānī and Abū Yūsuf (Ibn ʿĀbidīn, 2003) approved all types of movable properties as the subject matter for waqf. Imam Mālik bin Anas also agreed on both immovable and movable properties as a subject matter of waqf even if it is cash waqf. Cash waqf, which is based on a loan without interest, is permissible according to Mālikī jurists (Al-Ābī, 1970). With respect to the other two schools of fiqh (Islamic jurisprudence), both Imams al-Shāfiʿī and Ibn Ḥanbal also agreed on the validity of both immovable and movable properties as subject matter of waqf (Abū Zuhrah, 1959; Al-Zuhayli, 2002).
In the modern application of waqf, movable assets in the form of cash and other financial assets have been widely accepted by Muslim jurists. Financial assets refer to intangible properties that represent a claim on ownership of an entity or contractual rights to future economic benefits that may flow to the owner. In other words, a financial asset represents the contractual right to receive cash or other financial assets (Bouheraoua et al., 2014). Common types of financial assets include shares, ṣukūk and unit trusts. This provision enables people to contribute in establishing a waqf even if they do not personally own any real estate. The permissibility of making waqf using contemporary forms of wealth like cash, shares and unit trusts increases the flexibility of waqf and public participation in funding it.
The permissibility of unit trust as the subject matter of waqf was never specifically discussed by classical Muslim scholars. Hence, it is extremely necessary for the fatwa authorities as well as contemporary Muslim scholars to provide the interpretations on its permissibility according to the Sharīʿah to set the direction of its future implementation. There is only one Sharīʿah resolution concerning the permissibility of endowing unit trusts. In 2009, the International Islamic Fiqh Academy in its 19th meeting, held in the United Arab Emirates (UAE), resolved the permissibility of waqf in the form of financial instruments as follows: “It is permissible to endow shares (that are Sharīʿah compliant), ṣukūk, intangible rights, benefits and unit trusts, as they are all assets recognized by Sharīʿah” (International Islamic Fiqh Academy, (2009), Resolution No. 181 (7/19).
For the purpose of this study, the fatwas and discussions on the permissibility of cash waqf and waqf shares are relevant as they are strongly related to unit trusts, which are themselves likely to be constituted of shares, ṣukūk, or any other Sharīʿah-compliant securities. In conceptualizing the viable models of unit trust waqf, this study has also used the concepts of cash waqf and waqf shares.
### The legality of temporary waqf
Waqf muʾaqqat refers to the act of endowing assets for a specific period, after which they shall be returned to the original owner (wāqif). Classical Islamic jurists had differing opinions on this matter. The majority prohibited the practice of temporary waqf as it does not satisfy the condition of being perpetual, hence nullifying what they considered to be the fundamental nature of waqf (Al-Zuhayli, 2002).
However, temporary waqf is allowed by the Mālikī School, which opined that the permanent transfer of ownership is not a condition for a valid waqf (Al-Dardīr, 1991). Thus, they allowed endowing an asset for a specific period and having it returned to the original owner after the period ends (Al-Dardīr, 1991). For instance, a wāqif may specify to endow his house for a month; therefore, the ownership of the house shall be returned to him after the end of that period.
Temporary waqf is also allowed by some Shāfiʿī scholars (Al-Bujayrimī, 1995) in the sense that any particular beneficiary may receive the benefit of the waqf temporarily; however, according to this view, the ownership of the waqf will never return to the wāqif. For example, in the case of a house endowed as a waqf, any particular beneficiary may be replaced by another beneficiary after a period and so on. Temporary waqf, however, is not allowed for the waqf of mosques and cemeteries.
Kahf (2003) argues that although the principle of perpetuity is of high importance for waqf, the concept is sometimes carried too far to an extent that it restricts certain acts of benevolence, particularly in today’s world. Temporary waqf should be encouraged as sometimes it is needed in a few cases, for example in providing scholarship for students until graduation or maintaining an orphan until maturity.
Considering the potential of temporary waqf, and with the Mālikī precedent of considering it permissible, many fatwas have been issued by contemporary Sharīʿah authorities allowing it, among others:
• International Islamic Fiqh Academy, Resolution No. 181 (7/19), in its 19th meeting in 2009 (the United Arab Emirates);
• AAOIFI Sharīʿah Standard No. 33, Clause 3/1/4; and
• Selangor Fatwa Committee (Malaysia) 1/2014, 4.
### Waqf of unit trusts and temporary waqf in the Malaysian states’ legislation
The Federal Constitution of Malaysia confers the management and administration of waqf to the jurisdiction of the states. Hence, all affairs relating to waqf in Malaysia are administered by 14 different SIRCs or Majlis Agama Islam Negeri. That SIRCs act as the sole trustee for all waqf properties in every state is evident in all state enactments/acts. The SIRC, as the mutawallī (sole trustee), is responsible for preserving waqf properties, maximizing their revenues and distributing them. As such, remarkably, temporary waqf is legally possible to be practised within the current Malaysian legal framework.
Generally, a number of the state enactments allow for financial assets such as shares and unit trust to be endowed. One clear-cut example is in Section 10, Enactment Waqf (Perak) 2015, which illustrates the permissibility of unit trust being the subject matter of waqf, based on the definition of waqf of shares that also include “unit trusts”. In addition, the provisions of waqf muʾaqqat are traceable in a number of State Enactments such as:
• Section 17 of the Rules of Waqf Johor 1983;
• Section 2 of the Administration of Islamic Law (Federal Territories) Act 1993;
• Section 2 of Majlis Sarawak Ordinance 2001; and
• Enactment Waqf (Terengganu) 2016.
Most explicitly, the recent Enactment Waqf of Terengganu 2016 recognizes the applicability of “wakaf muaqqat” which is defined by the enactment as “a waqf dedication for a specific period of time”.
These legal provisions demonstrate that the modern application of waqf via contemporary financial assets and contemporary mechanisms has been recognized by a number of state authorities in Malaysia. Nevertheless, its application is yet to be tested within the current Islamic finance legal framework.
### Sustainable waqf fund investment strategy
Diversification is one of the key strategies in investments, as manifested by the popular saying, “Don’t put all your eggs in one basket.” This strategy is meant to ensure that investors will still get return from certain segments should any other segment lose its momentum with little or no return at all. According to Jim Garland, in the context of preserving the capital such as in a waqf fund, the most important strategy is to optimize the return for the beneficiaries rather than focusing on the capital appreciation (Dimson, 2007). Waqf funds left in a typical saving account are exposed to inflation risk that can be detrimental to the value of the fund in the long run (Wildermuth, 2012). As such, the best investment strategy is not merely to maintain the capital but also to consider the declining purchasing power of the waqf (Wildermuth, 2012). It is worth observing that in managing risks, only generated profits would be distributed to beneficiaries while preserving the original capital amount. Hence, portfolio rebalancing and active portfolio management are crucial to ensure the sustainability of waqf capital.
There are three important criteria that need to be addressed when managing waqf investments. First, the waqf capital should not be diminished; hence, protection of the capital should be a priority. Second, investments undertaken must be able to produce a stable and consistent income to be distributed to waqf beneficiaries for the waqf to be sustainable and to reap endless rewards from Allah (SWT). Third, all investments made for the waqf must be Sharīʿah compliant.
Kuwait Awqaf Public Foundation (KAPF) is an organization that is actively involved in managing waqf assets via contemporary approaches. It highlights three important criteria in waqf investment strategy, namely, the investments must be based on the Sharīʿah, and they must take into consideration the economic and diversification dimensions. To ensure this, the investment activities of KAPF focus on minimizing the risk to safeguard the waqf capital. Feasibility studies are prepared for any investment project, and investments are diversified in terms of location as well as portfolios and sectors including financial, real estate and services. Moreover, investment ceilings are defined for each sector (Al-Busharah, 2012).
Meanwhile, the International Islamic Fiqh Academy (2004) in Resolution no. 140 (6/15) in Muscat spelled out some important guidelines for waqf investment strategies that can be summarized as follows:
1. comply with Sharīʿah principles;
2. generate stable income while preserving waqf capital;
3. diversify the investment portfolio to minimize the risk of loss;
4. use various hedging mechanisms to avoid decline or loss of waqf capital;
5. conduct comprehensive research before investing in projects to ensure high success and great impact on the economy;
6. use prudent investment tools and avoid high-risk investments;
7. the investment method should be consistent with the nature of the waqf asset in maintaining the capital and ensuring the return to beneficiaries;
8. the ownership of movable waqf properties should be preserved from loss of ownership or illegal transfer;
9. if the movable waqf properties are in cash form, they should be invested in contracts such as muḍārabah, mushārakah, istiṣnaʿ and other contracts; and
10. the investment manager should be transparent in terms of reporting the operations, revenues and benefits distribution.
## Research design
This study is qualitative in nature and uses document research as the main method of analysis sourced from books, fatwa compilations, journal articles and other published sources. Based on the literature review, this study explores and identifies a number of important underlying themes related to unit trust waqf, as shown in Figure 1, which were used in formulating the relevant conceptual models.
Figure 1 depicts the conceptual framework of this study towards formulating the working models of unit trust waqf. First, the models are formulated with the objective of providing the possible mechanics for maximizing the benefits that can be potentially generated from cash waqf. Second, unit trust waqf models take into consideration some prudent and balanced investment strategies that are closely linked to the very objective of Islamic endowment, which is to safeguard the principal amount of waqf funds while generating sustainable returns to the beneficiaries. Apart from that, the establishment of unit trust waqf funds looks into cultivating the corporate management of waqf funds, among others, by promoting ethical and professional conduct by highly skilled managers of waqf institutions. Finally, the unit trust waqf models are foreseen to become the alternative models of Islamic social finance in multiplying the generated revenues for the beneficiaries and creating more job opportunities for the benefits of the society through direct engagement with real economic activities.
On the whole, the identification of the themes enables us to recognize some persistent concepts that are crucial towards the establishment of unit trust waqf. This realization will ensure that waqf properties are capable of generating continuous revenues for the beneficiaries as well as for the survival and revival of the waqf sector.
## Proposed unit trust waqf models
In the bid to ensure that the ummah’s economy will continue to grow, on-going research pertaining to waqf development can be regarded as an evergreen facet of harnessing the creation of new waqf instruments. Fundamentally, the creation of robust and strategic waqf development models can be narrowed down towards achieving three SIRC goals. The first is to convert the scattered and abandoned waqf assets into productive properties. The second is to enhance the performance of existing income-producing assets for better returns for waqf survival as well as for the beneficiaries’ benefit. Last, but not least, is to have a wide base for the waqf collection platform to optimize cash waqf collection through feasible structures.
In this section, Figures 2 through 6 present the proposed five models of unit trust waqf implementation.
In Figure 2:
• Step 1: The wāqif buys units from a unit trust then endows the units purchased by him or her.
• Step 2: The ownership of endowed units is held by the State Islamic Religious Council (SIRC) as the mutawallī, which is the sole trustee of the waqf.
• Step 3: The fund manager is responsible to invest the waqf-unit trust and manage the investment portfolio.
• Step 4: The investment returns will be distributed to beneficiaries. Where applicable, some portions of the returns are channelled for reinvestment purposes.
In Figure 3:
• Step 1: The wāqif endows the units purchased by him or her from a unit trust for a pre-determined period.
• Step 2: The ownership of the endowed units is held by the SIRC as the mutawallī, which is the sole trustee.
• Step 3: The fund manager is responsible to invest the endowed units and manage the investment portfolio.
• Step 4: The investment returns will be distributed to beneficiaries. Where applicable, some portions of the returns are channelled for reinvestment purposes.
• Step 5: After the waqf period ends, the ownership of the endowed units is returned to the original owner (wāqif).
In Figure 4:
• Step 1: The wāqif endows cash with the stipulation that the proceeds must be used to purchase units that are offered by the unit trust fund manager (hence, the purchased units will be declared as waqf assets, not the cash).
• Step 2: The proceeds will be used to purchase units in the unit trust fund and the ownership will be held by the mutawallī as the sole trustee.
• Step 3: The fund manager is responsible to invest the endowed units and manage the investment portfolio.
• Step 4: The investment returns will be distributed to beneficiaries. Where applicable, some portions of the returns will be reserved for reinvestment purposes.
In Figure 5:
• Step 1: Investors invest in a unit trust fund (but do not endow the units).
• Step 2: The fund manager is responsible to manage the investors’ investment portfolio.
• Step 3: Returns or dividends from the unit trust investment will be channelled to waqf and a partial amount will be used to purchase other units, which later will be declared as waqf and held by the mutawallī.
In Figure 6:
• Step 1: The fund managers endow the full or partial amount of the management fees that they have received and give a condition that the proceeds must be used to purchase unit trust (hence, the purchased units will be declared as waqf assets, not the cash).
• Step 2: The proceeds will be used to purchase units in a unit trust fund that will be held by the mutawallī as a sole trustee.
• Step 3: The fund manager is responsible to invest the endowed units and manage the investment portfolio.
• Step 4: The investment returns will be distributed to beneficiaries. Where applicable, some portions of the returns will be reserved for reinvestment purposes.
## Proposed parameters for implementing unit trust waqf
There are a number of issues that might arise related to the implementation of unit trust waqf. The issues include the fund’s compliance with Sharīʿah principles, supervision and governance of the fund, risk management of the portfolio to preserve the waqf capital from losses, and sustainability of the fund. Hence, to address this concern, this study further proposes the parameters for implementing unit trust waqf, which could be a useful reference for the stakeholders. These include the wāqif (donor), the mutawallī (administer of waqf), fund managers and Sharīʿah advisors. These parameters are designed to ensure the adherence of unit trust waqf activities to Sharīʿah principles and the existing waqf laws and regulations in Malaysia.
The proposed parameters are divided into several sections:
• legality of unit trust waqf from the standpoint of Sharīʿah and waqf laws and regulations in Malaysia;
• supervision of unit trust waqf investment;
• risk management; and
• sustainability of unit trust waqf investment.
Table I depicts the parameters for implementing unit trust waqf.
## Conclusion
Unit trust waqf is an Islamic financial innovation which could bring tremendous benefits to the waqf institution in Malaysia and other countries, besides those it provides for the waqf beneficiaries. However, the current conversation on unit trust waqf is still theoretical, with little guidance available regarding its implementation. In particular, there is a lack of modern fatwas on the permissibility (or prohibition) of this type of waqf from the Sharīʿah perspective. As such, this study was conducted to help enrich the relevant literature by shedding some light on its great potential as an investment mechanism that could help to sustain and further develop waqf assets in Malaysia. The real focus, however, is on its application and implementation. This is discussed against the backdrop of the Sharīʿah rulings on waqf of the asset classes relevant to unit trust. The key issues are the permissibility of endowments of movable assets, particularly cash, and by extension, securities. This is relevant because cash waqf proceeds would be used to purchase units and their underlying constituents such as ṣukūk and shares.
Our study found that there is no express text in the Qurʾān and Sunnah that explicitly prohibits or sanctions the unit trust waqf. The novelty of this study lies in the proposed models for channeling unit trusts for waqf purposes along with the parameters of their application that could be useful to waqf stakeholders in Malaysia. These could be given full consideration in its future implementation. This study is a part of many efforts from various quarters to promote the application of contemporary waqf, particularly unit trusts as a new category of waqf asset. Finally, and more importantly, unit trust waqf can be a vehicle towards encouraging more philanthropic and charitable activities among members of the society.
## Figures
### Figure 1.
Conceptual framework of unit trust waqf models
### Figure 2.
First proposed model: unit trust model
### Figure 3.
Second proposed model: waqf muʾaqqat model
### Figure 4.
Third proposed model: cash waqf for the purpose of purchasing units in a unit trust fund
### Figure 5.
Fourth proposed model: waqf of dividends
### Figure 6.
Fifth proposed model: waqf of the management fees
## Table I.
Parameters for implementing unit trust waqf
Parameters Description
Parameter 1: Sharīʿah compliance and legality 1/1 – Fund managers must ensure that all investment activities of the unit trust waqf are Sharīʿah compliant. This can be achieved by:
1/1/1 – Meeting the requirements for qualifying as Sharīʿah-compliant investment set by authoritative bodies such as the Sharīʿah Advisory Council (SAC) of Securities Commission Malaysia (SC) and that of Bank Negara Malaysia (BNM)
1/1/2 – Establishing a Sharīʿah committee which is responsible for reviewing and advising on Sharīʿah matters related to the unit trust waqf
1/2 – The entire process of establishing the unit trust waqf, for instance, collection of proceeds, marketing and promotion, investment, istibdāl and distribution of profits must be conducted in accordance to the national and/or state’s legal framework
Parameter 2: Supervision and oversight 2/1 – Supervisory and oversight responsibilities related to the governance and administration of the unit trust waqf fund include the following:
2/1/1 – The State Islamic Religious Council (SIRC) acts as the sole trustee (mutawallī) for the unit trust waqf fund
2/1/2 – The mutawallī has duties and responsibilities for supervision and oversight of the administration of the unit trust waqf. SIRCs may appoint any institution to perform the administrative duties on their behalf
2/1/3 – The amount of all fees due to the fund managers and their source of payment must be agreed between the mutawallī and the fund managers
2/1/4 The mutawallī must establish its own supervisory and governance framework to ensure the unit trust waqf funds are properly managed by the appointed fund managers
2/2 – Supervisory and oversight responsibilities related to the collection and distribution activities of unit trust waqf funds include the following:
2/2/1 – The mutawallī must decide which parties should be responsible for the collection and distribution functions of the unit trust waqf. The mutawallī is responsible for supervising the collection and distribution activities of unit trust waqf funds
2/2/2 – Wāqifs must ensure that their money or units which are intended to be endowed are channeled to authorized institutions by the SIRC
2/2/3 – In the event that money is collected from the wāqif for the purpose of investing in unit trust waqf funds, the wāqif must be informed that the proceeds will be used to purchase units in the unit trust funds. Hence, the purchased units will be declared as the waqf assets instead of the cash channeled by the wāqif
2/2/4 – The unit trusts endowed by the wāqif must be Sharīʿah compliant
2/2/5 – The appointed fund managers are encouraged to endow some of the management fees received by them to purchase more units for the purpose of waqf
2/2/6 – All promotion and marketing activities associated with the unit trust waqf must correspond with the ultimate objective of waqf and not solely be profit-driven or be biased towards the interest of certain individuals or a group of people
2/2/7 All relevant information on the unit trust waqf must be provided to the wāqif or investors in a transparent and timely manner
2/3 – Supervisory and oversight responsibilities related to the investment of unit trust funds include the following:
2/3/1 – The mutawallī has duties and responsibilities for supervision and oversight of the investment activities of the unit trust waqf
2/3/2 – The mutawallī must equip itself with adequate knowledge and expertise of supervising unit trust waqf investment activities
2/3/3 –to manage the unit trust waqf, the SIRC shall appoint fund managers to manage it for certain fees as agreed upon by both parties
2/3/4 – Fund managers appointed by the mutawallī must have knowledge, expertise and capabilities to manage the waqf funds in such a way that consistent returns can be generated and the initial capital can be protected
2/3/5 – Fund managers must determine the risk tolerance level, investment strategies and governance framework for the unit trust waqf investment, which must be agreed by the mutawallī
2/3/6 – Supervision of unit trust waqf investment activities must be done on an ongoing basis
2/3/7 – Guidelines or clear-cut Standard Operating Procedures (SOPs) for supervision of unit trust waqf investment should be established by the mutawallī
2/3/8 – Report on unit trust waqf investment must be made publicly available
2/3/9 – Effective communication and cooperation between the mutawallī and fund managers are crucial for ensuring the sustainability of unit trust waqf investments
Parameter 3: Risk management 3/1 – Fund managers should establish an effective risk management system and due diligence process
3/2 – Capital protection must be placed as the ultimate objective of unit trust waqf investments
3/3 – Unit trust waqf investments must achieve balance between profitability and capital protection
3/4 – Fund managers are responsible to ensure that unit trust waqf funds are not exposed to extremely high investment risks that can devalue their capital in the long run
3/5 – Fund managers must ensure that waqf proceeds are not invested in highly volatile asset classes
3/6 – Fund managers must create highly diversified portfolios of unit trust waqf investments
3/7 – The process of istibdāl (e.g. selling units and using the receipts to purchase other units) in unit trust waqf investments can be done in the following situations:
The wāqif has stipulated that istibdāl must be done through asset trading
The unit trust funds experience significant capital loss where high maintenance and management expenditures have to be borne by the mutawallī
The unit trust funds and their constituent assets become Sharīʿah non-compliant
3/8 – Istibdāl can only be done with the consent of the mutawallī and must not expose the unit trust waqf funds to high investment risks
Parameter 4: Sustainability 4/1 – The mutawallī must balance the primary objectives of sustainability of unit trust waqf investment and distribution of benefits to the waqf beneficiaries
4/2 – In view of enhancing the sustainability of unit trust waqf funds, the fund managers must take measures that promote sustainable capital growth and ensure consistent returns for the beneficiaries
4/3 – In the event capital deterioration has occurred in previous years, the returns generated in the succeeding years must be used to purchase new units to restore the initial value of unit trust waqf funds (i.e., keep capital intact)
4/4 – The mutawallī must ensure that management fees and other expenditures are paid before returns can be distributed to the beneficiaries
4/5 – Some investment profits may be retained as a capital reserve for the purpose of reinvestment
4/6 – All promotion and marketing activities related to unit trust waqf investment must be actively conducted
4/7 – Various forms of incentives may be provided to investors or wāqifs such as subsidizing management fees and providing tax rebates
Source: Authors’ own
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## Corresponding author
Syahnaz Sulaiman can be contacted at: syahnaz@usim.edu.my | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.24396933615207672, "perplexity": 9242.144527860626}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 20, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2022-33/segments/1659882570651.49/warc/CC-MAIN-20220807150925-20220807180925-00347.warc.gz"} |
https://camb.readthedocs.io/en/stable/bbn.html | BBN models¶
class camb.bbn.BBNPredictor[source]
The base class for making BBN predictions for Helium abundance
Y_He(ombh2, delta_neff=0.0)[source]
Get BBN helium mass fraction for CMB code.
Parameters: ombh2 – $$\Omega_b h^2$$ delta_neff – additional N_eff relative to standard value (of 3.046) Y_He helium mass fraction predicted by BBN
Y_p(ombh2, delta_neff=0.0)[source]
Get BBN helium nucleon fraction. Must be implemented by extensions.
Parameters: ombh2 – $$\Omega_b h^2$$ delta_neff – additional N_eff relative to standard value (of 3.046) Y_p helium nucleon fraction predicted by BBN
class camb.bbn.BBN_fitting_parthenope(tau_neutron=None)[source]
Old BBN predictions for Helium abundance using fitting formulae based on Parthenope (pre 2015).
Y_p(ombh2, delta_neff=0.0, tau_neutron=None)[source]
Get BBN helium nucleon fraction. # Parthenope fits, as in Planck 2015 papers
Parameters: ombh2 – $$\Omega_b h^2$$ delta_neff – additional N_eff relative to standard value (of 3.046) tau_neutron – neutron lifetime $$Y_p^{\rm BBN}$$ helium nucleon fraction predicted by BBN
class camb.bbn.BBN_table_interpolator(interpolation_table='PArthENoPE_880.2_standard.dat', function_of=('ombh2', 'DeltaN'))[source]
BBN predictor based on interpolation from a numerical table calculated by a BBN code.
Tables are supplied for Parthenope 2017 (PArthENoPE_880.2_standard.dat, default), similar but with Marucci rates (PArthENoPE_880.2_marcucci.dat), and PRIMAT (PRIMAT_Yp_DH_Error.dat).
Parameters: interpolation_table – filename of interpolation table to use. function_of – two variables that determine the interpolation grid (x,y) in the table, matching top column label comment. By default ombh2, DeltaN, and function argument names reflect that, but can also be used more generally.
DH(ombh2, delta_neff=0.0, grid=False)[source]
Get deuterium ratio D/H by interpolation in table
Parameters: ombh2 – $$\Omega_b h^2$$ (or, more generally, value of function_of[0]) delta_neff – additional N_eff relative to standard value (of 3.046) (or value of function_of[1]) grid – parameter for RectBivariateSpline (whether to evaluate the results on a grid spanned by the input arrays, or at points specified by the input arrays) D/H
Y_p(ombh2, delta_neff=0.0, grid=False)[source]
Get BBN helium nucleon fraction by intepolation in table.
Parameters: ombh2 – $$\Omega_b h^2$$ (or, more generally, value of function_of[0]) delta_neff – additional N_eff relative to standard value (of 3.046) (or value of function_of[1]) grid – parameter for RectBivariateSpline (whether to evaluate the results on a grid spanned by the input arrays, or at points specified by the input arrays) Y_p helium nucleon fraction predicted by BBN. Call Y_He() to get mass fraction instead.
get(name, ombh2, delta_neff=0.0, grid=False)[source]
Get value for variable “name” by intepolation from table (where name is given in the column header comment) For example get(‘sig(D/H)’,0.0222,0) to get the error on D/H
Parameters: name – string name of the parameter, as given in header of interpolation table ombh2 – $$\Omega_b h^2$$ (or, more generally, value of function_of[0]) delta_neff – additional N_eff relative to standard value (of 3.046) (or value of function_of[1]) grid – parameter for RectBivariateSpline (whether to evaluate the results on a grid spanned by the input arrays, or at points specified by the input arrays) Interpolated value (or grid)
camb.bbn.get_predictor(predictor_name=None)[source]
Get instance of default BBNPredictor class. Currently numerical table interpolation as Planck 2018 analysis. | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 1, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.6631185412406921, "perplexity": 14422.150589485469}, "config": {"markdown_headings": false, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2020-10/segments/1581875145621.28/warc/CC-MAIN-20200221233354-20200222023354-00255.warc.gz"} |
http://slideplayer.com/slide/4156371/ | # Chapter 16 Principles of Conventional Pressure transducers
## Presentation on theme: "Chapter 16 Principles of Conventional Pressure transducers"— Presentation transcript:
Chapter 16 Principles of Conventional Pressure transducers
An understanding of the correct principle according to which an invention operates may follow, instead of precede, the making of the invention. Clemens Herschel (1837)
DEFINITIONS In general, a transducer a device that, being actuated by energy from one system, supplies energy (in any form) to another system. In particular, the essential feature of a conventional pressure transducer is an elastic element, which converts energy from the pressure system under study to a displacement in the mechanical measuring system.
An additional feature found in many pressure transducers is an electric element which, in turn, converts the displacement of the mechanicals system to an electric signal. The popularity of electric element pressure transducers derives from the ease with which electric signals can be amplified, transmitted, controlled, and measured. Electrical pressure transducers can be delineated further as follows: An active transducer is one that generates its own electrical output as a function of the mechanical displacement, whereas a passive transducer (i.e., one dependent on a change in electrical impedance) requires an auxiliary electrical input which it modifies (modulates) as a function of the mechanical displacement for its electrical output (Figure 16.1) [1]-[4].
Examples of mechanical pressure transducers having elements only are deadweight free-piston gauges, manometers, bourdon tubes, bellows, and diaphragm gauges. An example of an active electrical pressure transducer, combining in one the elastic and electric elements, is the piezoelectric pickup. Examples of electric elements employed in passive electrical pressure transducers include strain gauges, slide-wire potentiometers, capacitance pickups, linear differential transformers, variable reluctance units, and the like. Some of the more commonly used mechanical and electrical pressure transducers are considered next.
16.2 MECHANICAL PRESSURE TRANSDUCERS
We have already described several types of mechanical pressure transducers in the discussion of manometer pressure standards. In addition, there are manometers not considered standards, yet used as conventional transducers. These include the well, inclined, and Zimmerli types of manometers. In these, as in all manometers, the elastic element is the manometric fluid itself, which is moved by an applied pressure difference
Well Type The well-type manometer offers the advantage of a single-scale reading for the pressure difference, the hope being that the level variation in the well either is negligible or can be accounted for in the construction of the single-tube scale.
Following the notation of Figure 16
Following the notation of Figure 16.2, the pertinent equation is Figure16.2. A well-type manometer pressure transducer: If D 》d, (say on the order of 500 to 1), variations in the well level can be neglected.
Inclined Type The inclined-type manometer provides a single scale reading that is expanded along the single tube (i.e., the scale has more graduations per unit vertical height than the equivalent vertical scale of the well-type manometer). This allows for greater readability (on the order of ± 0.01 in.) than in the U-tube manometer. The angle of incline (α) is generally about 10° from the horizontal (see Figure 16.3).
Zimmerli type The Zimmerli-type manometer [5] is another special form of manometer that features high readability at the lower absolute pressures (range is 0 to 100 mm Hg within 0.1 mm Hg). A mercury column is first separated by simultaneously applying the pressures to be measured to both sides of the mercury.
The resulting void between the two mercury columns (which occurs at an applied pressure of about 140 mm Hg) produces a near-absolute zero reference for the measurement. Any decrease in pressure beyond the separation point causes the mercury to drop in the reference leg and to rise in the measuring leg of the gauge until, at a pressure of about 0.1 mm Hg in the elevations of mercury in the two legs I apparent. This, of course, represents the limit of usefulness of the Zimmerli manometer (Figure 16.4). ,
Bourdon Tube In the bourdon tube transducer, the elastic element is a small-volume tube, fixed at one end, which is open to accept the applied pressure, but free at the other end, which is closed to allow displacement under the deforming action of the pressure difference across the tube walls. In the most common model, a tube of oval cross section is bent in a circular arc. Under pressure, the oval-shaped tube to become circular, with a subsequent increase in the radius of the circular arc.
By an almost frictionless linkage, the free end of the tube rotates a pointer over a calibrated scale to give a mechanical indication of pressure (see Figure 16.5) ranges of absolute, gauge, and differential pressure measurements within a calibration uncertainty of 0.1% of the reading. In contrast to the large angular displacements encountered in the mechanical-output bourdon gauges already described, the elastic element most often used in conjunction with electric elements (to yield electrical outputs) takes the form of a flattened tube that is twisted about its own longitudinal axis and exhibits very small angular displacements (Figure 16.7) .
Bellows Another elastic element used in pressure transducers takes the form of a bellows. In one arrangement, pressure is applied to one side of a bellows , and the resulting deflection is partly counterbalanced by a spring (Figure 16.8). In another differential arrangement, one pressure is applied to the inside of one scaled bellows while the other pressure is led to the inside of another sealed bellows. By suitable linkages, the pressure difference is indicated by a pointer.
Diaphragm A final elastic element to be mentioned because of its widespread use in pressure transducers is the diaphragm (Figure 16.9). Such elements can appear in the form of flat, corrugated, or dished plates. The choice depends on the strength and amount of deflection desired. The literature on diaphragms is quite extensive and should be consulted for detailed information on diaphragm characteristics and on diaphragm-type pressure transducers [6], [7]. In high-precision instruments, a pair of diaphragms is used back to back to form an elastic capsule.
One Pressure is applied to the inside of the capsule, which is surrounded on the outside by the other pressure. Such a differential pressure transducer exhibits the unique feature of a calibration that is almost independent (within 0.1 % ) of pressure level effects .
16. 3 Electrical Pressure transducers
An Active Electrical Pressure transducer A piezoelectric element provides the basis for the only active electrical pressure transducer in common use. It operates on a principle discovered in the 1880s by the Curie brothers that certain crystals ( i.e, those not possessing a center of symmetry ) produce a surface potential difference When they are stressed in appropriate directions [ 8 ],, [ 9 ] . Quartz, Rochelle salt , barium-titanate , and lead-zirconate-titanate are some of the common crystals that exhibit usable piezoelectricity .
Pressure pickups designed around such active elements have the crystal geometry oriented to give maximum piezoelectric response in a desired direction with little or no response in other directions. Sound pressure instrumentation makes extensive use of piezoelectric pickups in such forms as hollow cylinders, disks, and so on.
Piezoelectric pressure transducers are also used in measuring rapidly fluctuating aerodynamic pressures or for short-term transients such as those encountered in shock tubes. Although the emf developed by a piezoelectric element may be proportional to pressure, it is nonetheless difficult to calibrate by normal static procedures. An attractive technique called “electrocalibration “has been described in the recent literature [10]. In this procedure, the piezoelectric pressure transducer is excited by an electric field rather than by an actual physical pressure to obtain the calibrations.
Passive Electrical Pressure transducers
Of the passive electrical pressure transducers, none are more common than the variable resistance types. STRAIN GAUGE Types . Electric elements of this type operate on the principle that the electrical resistance of a wire varies with its length under load (i. e., with strain). In the unbounded type, four wires run free between four electrically insulated pins located two on a fixed frame and two on a movable armature. The wires are installed under an initial tension and form the active legs of a conventional bridge circuit (see Figure ).
Under pressure, the elastic element (usually a diaphragm) displaces the armature, causing two of the wires to elongate while reducing the tension in the remaining two wires. This change in resistance causes a bridge imbalance proportional to the applied pressure , and these quantities can be related by calibration. The use of four wires in the manner indicated makes for increased bridge sensitivity , and allowing the wires to run free between the pins causes a high natural frequency for the transducer [ 11 ] . In the bonded type , the strain gauge takes the form of a fine wire filament , set in cloth , paper , or plastic , and fastened by a suitable cement to a flexible plate that takes the load of the elastic element ( see Figure ) . .
Often two strain gauge elements are connected to the bridge in an attempt to nullify unavoidable temperature effects. The electrical energy input, required for all passive transducers, is in the case the excitation voltage of the bridge. The nominal bridge output impedance of most strain gauge pressure transducers is 350 The nominal excitation voltage is 10V (ac or dc.) The natural frequency can be as high as 50, 000 cps. Transducer resolution is infinite, and the usual calibration uncertainty of such gauges is within 1 % of full scale.
Figure 16. 10 Typical unbonded strain gauge.
Figure 16.11 typical bonded strain gauge .
Figure 16.12 Linear variable differential transformer (LVDT. )
Potentiometer Type Other pressure transducers of the variable resistance type operate on the principle of movable contacts such as those found in slide-wire rheostats or potentiometers. In one arrangement, the elastic element is a helical bourdon tube, and a precision wire-wound potentiometer serves as the electric element. As pressure is applied to the open end of the bourdon, it unwinds and causes the wiper (which is connected directly to the closed end of the bourdon) to move over the potentiometer, thus varying the resistance of a suitable measuring circuit.
Capacitance TYPE In the variable capacitance-type pressure transducer, the elastic element is usually a metal diaphragm that serves as one plate of a capacitor. If pressure is applied, the diaphragm moves with respect to a fixed plate to change the thickness of the dielectric between the plates. By means of a suitable bridge circuit, the variation in capacitance can be measured and related to pressure by calibration. Several variable inductance types of pressure transducers are considered next.
LINEAR VARIABLE Differential Transformer TYPE (LVDT)
The electric element in a LVDT is made up of three coils mounted in a common frame. A magnetic core centered in the coils is free to be displaced by an elastic element of either the bellows, bourdon, or diaphragm type (see Figure ). The center coil is the primary winding of the transformer and as such has an ac excitation voltage impressed across it. The two outside coils form the secondaries of the transformer. When the core is centered, the induced voltages in these two outer coils are equal and out of phase; this represents the zero pressure-position.
However, when the core is displaced by the action of an applied pressure, the voltage induced in one secondary increases, whereas that in the other decreases. This output voltage difference varies essentially linearly with pressure for the small core displacements allowed in LVDT pressure transducers; this voltage difference is measured and related to the applied pressure by calibration. In one variation of the above [12], a servo-amplifier operates on the electrical output of the LVDT and causes the core to return to its null position for each applied pressure. Simultaneously it produces an appropriate electrical output signal ( see Figure 16 · 13 ) .
Variable Reluctance Types
Another class of pressure transducers whose electrical output signals are ultimately derived from variable inductances in the measuring circuits operates on the principle of a movable magnetic vane in a magnetic field. In one type, the elastic element is a flat magnetic diaphragm located between two magnetic output coils. Displacement of the diaphragm , caused by the applied pressure , changes the inductance ratio between the output coils and results in an output voltage proportional to the applied pressure ( see Figure ) .
In a final type , the elastic element is a flat twisted tube such as already described in the section on bourdon tubes ( see Figure 16.7 ) . A flat magnetic armature, connected directly to the closed end of the bourdon, rotates slightly when a pressure is applied. The accompanying small changes in the air gap between the armature and electromagnetic output coils alter the inductances in a bridge-type circuit. This variation in circuit inductance is used to modulate the amplitude or frequency of a carrier voltage, with the net result being an electrical response that is proportional to the applied pressure [13].
Figure 16.14 Magnetic reluctance differential pressure transducer (after Pace Wiancko literature.) | {"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8206213712692261, "perplexity": 1604.081231089533}, "config": {"markdown_headings": true, "markdown_code": false, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2018-13/segments/1521257650685.77/warc/CC-MAIN-20180324132337-20180324152337-00089.warc.gz"} |
http://rcd.ics.org.ru/authors/detail/1583-michael_deryabin | 0
2013
Impact Factor
# Michael Deryabin
119899, Moscow, Vorobyevy gory
Depatment of Mechanics and Mathematics, M.V.Lomonosov Moscow State University
## Publications:
Deryabin M. V., Pustyl'nikov L. D. Generalized relativistic billiards 2003, vol. 8, no. 3, pp. 283-296 Abstract We study generalized relativistic billiards, which is the following dynamical system. A particle moves in the interior of a domain under the influence of some force fields. As the particle hits the boundary of the domain, its velocity is transformed as if the particle underwent an elastic collision with a moving wall. Both the motion in the domain and the reflection are considered in the framework of the theory of relativity. We study the periodic and "monotone" action of the boundary for the particle moving in a parallelepiped and in an arbitrary compact domain respectively, and we also consider an "accelerating" model in an unbounded domain. We prove that under some general conditions an invariant manifold in the velocity phase space of the generalized billiard, where the particle velocity equals the velocity of light, either is an exponential attractor or contains one. Thus for an open set of initial conditions the particle energy tends to infinity. Citation: Deryabin M. V., Pustyl'nikov L. D., Generalized relativistic billiards , Regular and Chaotic Dynamics, 2003, vol. 8, no. 3, pp. 283-296 DOI:10.1070/RD2003v008n03ABEH000244
Deryabin M. V., Hjorth P. G. High dimensional bowling. $n$-dimensional ball rolling on $(n – 1)$-dimensional surface 2003, vol. 8, no. 3, pp. 319-329 Abstract We consider the non-holonomic system of a $n$-dimensional ball rolling on a $(n – 1)$-dimensional surface. We discuss the structure of the equations of motion, the existence of an invariant measure and some generalizations of the problem. Citation: Deryabin M. V., Hjorth P. G., High dimensional bowling. $n$-dimensional ball rolling on $(n – 1)$-dimensional surface , Regular and Chaotic Dynamics, 2003, vol. 8, no. 3, pp. 319-329 DOI:10.1070/RD2003v008n03ABEH000248
Deryabin M. V. On asymptotics of the solution of Chaplygin equation 1998, vol. 3, no. 1, pp. 93-97 Abstract Chaplygin problem on a heavy rigid body falling in the ideal vortexless fluid resting at infinity. As it is well-known, without "initial impact", for almost all initial condition the rigid body tends to fall with its widest side ahead. The asymptotical expression for the solution of Chaplygin equation for large time t is found. It is numerically proved as well that with the "initial impact" the rigid body tends to fall with widest side ahead. Citation: Deryabin M. V., On asymptotics of the solution of Chaplygin equation, Regular and Chaotic Dynamics, 1998, vol. 3, no. 1, pp. 93-97 DOI:10.1070/RD1998v003n01ABEH000065 | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9505109786987305, "perplexity": 739.0199276653509}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2019-26/segments/1560627998376.42/warc/CC-MAIN-20190617043021-20190617065021-00158.warc.gz"} |
https://www.esaral.com/q/show-that-each-one-of-the-following-systems-of-equations-is-inconsistent-16064 | # Show that each one of the following systems of equations is inconsistent.
Question:
Show that each one of the following systems of equations is inconsistent.
$6 x+4 y=5$
$9 x+6 y=8$
Solution:
To prove: Set of given lines are inconsistent. | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9796015620231628, "perplexity": 291.5130070281878}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2023-06/segments/1674764500365.52/warc/CC-MAIN-20230206212647-20230207002647-00861.warc.gz"} |
https://drexel.edu/coas/academics/departments-centers/mathematics/events/seminars-colloquia/event-details/?eid=25887&iid=71103 | For a better experience, click the icon above to turn off Compatibility Mode, which is only for viewing older websites.
# Math Colloquium: Complexifications and Isometries
Wednesday, November 13, 2019
3:00 PM-4:00 PM
Edward Poon, Embry-Riddle Aeronautical University
Abstract: Given a norm $\| \cdot \|$ on a real Banach space $X$, there is a smallest ‘reasonable’ complexification norm $\| \cdot \|_C$ on the complexified space $X_C$, defined by $$\| x+ iy \|_C = \sup \{\|x \cos \theta + y \sin \theta \| : \theta \in [0, 2\pi]\}$$ for $x,y \in X$. Provided $X$ has a certain finiteness condition (possessed by all finite-dimensional spaces) we characterize the isometries for $\| \cdot \|_C$ in terms of the isometries for $\| \cdot \|$.
Georgi Medvedev
gsm29@drexel.edu
## Location
Korman Center, Room 243, 15 S. 33rd Street, Philadelphia, PA 19014
• Everyone | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 1, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.5421755909919739, "perplexity": 3345.135831819936}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2019-47/segments/1573496668699.77/warc/CC-MAIN-20191115171915-20191115195915-00499.warc.gz"} |
http://mathhelpforum.com/trigonometry/125061-trigs-logs.html | 1. ## Trigs and logs
Attached Thumbnails
2. Originally Posted by Tarwamin
So, you need help with problem 6? what have you tried?
3. I tried it wen it was secx but my teacher told me to do cscx so i dont noe how to do that
4. Originally Posted by Tarwamin
I tried it wen it was secx but my teacher told me to do cscx so i dont noe how to do that
Start that one by working with the left hand side because it is more complicated.
$\sin{x}+\sin{x}\cot^2{x}=\csc{x}$
Factor out a sine
$\sin{x}(1+\cot^2{x})=\csc{x}$
But, we know that $1+\cot^2{x}=\csc^2{x}$
So, now we get
$\sin{x}\csc^2{x}=\csc{x}$
But, we also know that $$\frac{1}{\csc^2{x}}=frac{1}{\sin^2{x}}$$
So, now we get
$\sin{x}\frac{1}{\sin^2{x}}=\csc{x}$
You should be able to take it from here.
5. thank you so much! | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 1, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 5, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.953249454498291, "perplexity": 1098.79936775527}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2016-44/segments/1476988719784.62/warc/CC-MAIN-20161020183839-00565-ip-10-171-6-4.ec2.internal.warc.gz"} |
https://arxiv.org/abs/1106.4646 | math.MG
(what is this?)
# Title:Classification of Sol lattices
Abstract: $\SOL$ geometry is one of the eight homogeneous Thurston 3-geomet-ri-es $$\EUC, \SPH, \HYP, \SXR, \HXR, \SLR, \NIL, \SOL.$$ In \cite{Sz10} the {\it densest lattice-like translation ball packings} to a type (type {\bf I/1} in this paper) of $\SOL$ lattices has been determined. Some basic concept of $\SOL$ were defined by {\sc{P. Scott}} in \cite{S}, in general.
In our present work we shall classify $\SOL$ lattices in an algorithmic way into 17 (seventeen) types, in analogy of the 14 Bravais types of the Euclidean 3-lattices, but infinitely many $\SOL$ affine equivalence classes, in each type. Then the discrete isometry groups of compact fundamental domain (crystallographic groups) can also be classified into infinitely many classes but finitely many types, left to other publication. To this we shall study relations between $\SOL$ lattices and lattices of the pseudoeuclidean (or here rather called Minkowskian) plane \cite{AQ}. Moreover, we introduce the notion of $\SOL$ parallelepiped to every lattice type. From our new results we emphasize Theorems 3-4-5-6.
In this paper we shall use the affine model of $\SOL$ space through affine-projective homogeneous coordinates \cite{M97} which gives a unified way of investigating and visualizing homogeneous spaces, in general.
Comments: 34 pages, 9 figures Subjects: Metric Geometry (math.MG) MSC classes: 22E25, 22E40, 57M60, 53A35 Cite as: arXiv:1106.4646 [math.MG] (or arXiv:1106.4646v1 [math.MG] for this version)
## Submission history
From: Jenö Szirmai [view email]
[v1] Thu, 23 Jun 2011 08:07:59 UTC (180 KB) | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 1, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.7752705812454224, "perplexity": 3342.230443852209}, "config": {"markdown_headings": true, "markdown_code": false, "boilerplate_config": {"ratio_threshold": 0.3, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2019-51/segments/1575541297626.61/warc/CC-MAIN-20191214230830-20191215014830-00058.warc.gz"} |
http://lhcbproject.web.cern.ch/lhcbproject/Publications/LHCbProjectPublic/LHCb-PAPER-2018-048.html | # Measurement of $B^+$, $B^0$ and $\Lambda_b^0$ production in $p\mkern 1mu\mathrm{Pb}$ collisions at $\sqrt{s_{NN}} = 8.16 \ \rm TeV$
[to restricted-access page]
## Abstract
The production of $B^+$, $B^0$ and $\Lambda_b^0$ hadrons is studied in proton-lead collisions at a centre-of-mass energy per nucleon pair of $\sqrt{s_\mathrm{NN}}=8.16 {\rm TeV}$ recorded with the LHCb detector at the LHC. The measurement uses a dataset corresponding to an integrated luminosity of $12.2\pm0.3 \mathrm{nb}^{-1}$ for the case where the proton beam is projected into the LHCb detector (corresponding to measuring hadron production at positive rapidity) and $18.6\pm0.5 \mathrm{nb}^{-1}$ for the lead beam projected into the LHCb detector (corresponding to measuring hadron production at negative rapidity). Nuclear effects are probed through double-differential cross-sections, forward-to-backward cross-section ratios and nuclear modification factors of the beauty hadrons. The double-differential cross-sections are measured as a function of the beauty-hadron transverse momentum and rapidity in the nucleon-nucleon centre-of-mass frame. Forward-to-backward cross-section ratios and nuclear modification factors indicate a significant nuclear suppression at positive rapidity. The ratio of $\Lambda_b^0$ over $B^0$ production cross-sections is reported and is consistent with the corresponding measurement in $pp$ collisions.
Invariant mass distribution of $B ^+$ candidates reconstructed in the $B ^+ \rightarrow \overline{ D } {}^0 \pi ^+$ decay for (left) $p\mkern 1mu\mathrm{Pb}$ and (right) $\mathrm{Pb}\mkern 1.5mu p$ collisions, with the fit result superimposed. The solid blue line, the solid green line, the cross-shaded area, the brown shaded area and the red shaded area represent the total fit, the signal component, the partially reconstructed background, the combinatorial background and $B ^+ \rightarrow \overline{ D } {}^0 K ^+$ decays, respectively. Fig1a.pdf [24 KiB] HiDef png [571 KiB] Thumbnail [333 KiB] *.C file Fig1b.pdf [24 KiB] HiDef png [581 KiB] Thumbnail [335 KiB] *.C file Invariant mass distribution of $B ^+$ candidates reconstructed in the $B ^+ \rightarrow { J \mskip -3mu/\mskip -2mu\psi \mskip 2mu} K ^+$ decay for (left) $p\mkern 1mu\mathrm{Pb}$ and (right) $\mathrm{Pb}\mkern 1.5mu p$ collisions, with the fit result superimposed. The solid blue line, the solid green line, the cross-shaded area, the brown shaded area and the red shaded area represent the total fit, the signal component, the partially reconstructed background, the combinatorial background and $B ^+ \rightarrow { J \mskip -3mu/\mskip -2mu\psi \mskip 2mu} \pi ^+$ decays, respectively. Fig2a.pdf [25 KiB] HiDef png [299 KiB] Thumbnail [215 KiB] *.C file Fig2b.pdf [23 KiB] HiDef png [311 KiB] Thumbnail [230 KiB] *.C file Invariant mass distribution of $B ^0$ candidates reconstructed in the $B ^0 \rightarrow D ^- \pi ^+$ decay for (left) $p\mkern 1mu\mathrm{Pb}$ and (right) $\mathrm{Pb}\mkern 1.5mu p$ collisions, with the fit result superimposed. The solid blue line, the solid green line, the cross-shaded area, the brown shaded area and the red shaded area represent the total fit, the signal component, the partially reconstructed background, the combinatorial background and $B ^0 \rightarrow D ^- K ^+$ decays, respectively. Fig3a.pdf [26 KiB] HiDef png [411 KiB] Thumbnail [255 KiB] *.C file Fig3b.pdf [28 KiB] HiDef png [425 KiB] Thumbnail [279 KiB] *.C file Invariant mass distribution of $\Lambda ^0_ b$ candidates reconstructed in the $\Lambda ^0_ b \rightarrow \Lambda ^+_ c \pi ^-$ decay for (left) $p\mkern 1mu\mathrm{Pb}$ and (right) $\mathrm{Pb}\mkern 1.5mu p$ collisions, with the fit result superimposed. The solid blue line, the solid green line, the cross-shaded area, the brown shaded area and the red shaded area represent the total fit, the signal component, the partially reconstructed background, the combinatorial background and $\Lambda ^0_ b \rightarrow \Lambda ^+_ c K ^-$ decays, respectively. Fig4a.pdf [27 KiB] HiDef png [337 KiB] Thumbnail [226 KiB] *.C file Fig4b.pdf [28 KiB] HiDef png [355 KiB] Thumbnail [255 KiB] *.C file Production cross-section of $B ^+$ mesons as a function of (left) $p_{\mathrm{T}}$ in $y$ bins and (right) $y$ integrated over $p_{\mathrm{T}}$ . The vertical bars (boxes) show statistical (total) uncertainties. Fig5a.pdf [15 KiB] HiDef png [173 KiB] Thumbnail [166 KiB] *.C file Fig5b.pdf [14 KiB] HiDef png [101 KiB] Thumbnail [108 KiB] *.C file Production cross-section of $B ^0$ mesons as function of (left) $p_{\mathrm{T}}$ in $y$ bins and (right) $y$ integrated over $p_{\mathrm{T}}$ . The vertical bars (boxes) show statistical (total) uncertainties. Fig6a.pdf [15 KiB] HiDef png [178 KiB] Thumbnail [171 KiB] *.C file Fig6b.pdf [14 KiB] HiDef png [108 KiB] Thumbnail [117 KiB] *.C file Production cross-section of $\Lambda ^0_ b$ baryons as a function of (left) $p_{\mathrm{T}}$ in $y$ bins and (right) $y$ integrated over $p_{\mathrm{T}}$ . The vertical bars (boxes) show statistical (total) uncertainties. Fig7a.pdf [15 KiB] HiDef png [179 KiB] Thumbnail [171 KiB] *.C file Fig7b.pdf [14 KiB] HiDef png [111 KiB] Thumbnail [118 KiB] *.C file Production cross-section ratios of $\Lambda ^0_ b$ baryons over $B ^0$ mesons and of $B ^0$ mesons over $B ^+$ mesons (top) as a function of $y$ integrated over $p_{\mathrm{T}}$ and as a function of $p_{\mathrm{T}}$ for (bottom left) $2.5 ## Tables and captions Signal yields in the range$2< p_{\mathrm{T}} <20\text{ Ge V /}c $and$1.5< y <3.5$($-4.5< y <-2.5$) for$ p\mkern 1mu\mathrm{Pb}$($\mathrm{Pb}\mkern 1.5mu p$) collisions. Uncertainties are statistical only. Table_1.pdf [50 KiB] HiDef png [88 KiB] Thumbnail [42 KiB] tex code Summary of systematic uncertainties (in %) for the measured cross-sections for different decay modes in$ p\mkern 1mu\mathrm{Pb}$. The ranges correspond to the minimum and maximum values over the$ p_{\mathrm{T}}$and$ y$bins of the measurement. Table_2.pdf [56 KiB] HiDef png [102 KiB] Thumbnail [48 KiB] tex code Summary of systematic uncertainties (in %) for the measured cross-sections for different decay modes in$\mathrm{Pb}\mkern 1.5mu p$. The ranges correspond to the minimum and maximum values over the$ p_{\mathrm{T}}$and$ y$bins of the measurement. Table_3.pdf [56 KiB] HiDef png [102 KiB] Thumbnail [48 KiB] tex code Differential cross-sections of$ B ^+ $,$ B ^0$and$\Lambda ^0_ b $production in bins of$ p_{\mathrm{T}}$and$y$,$\frac{{\rm d}^2\sigma}{{\rm d} p_{\mathrm{T}} {\rm d}y}( \upmu\text{b} /[ \text{ Ge V /}c ])$, and in bins of$y$integrated over$2< p_{\mathrm{T}} <20\text{ Ge V /}c $,$\frac{{\rm d}\sigma}{{\rm d}y} ( \upmu\text{b} )$. The first uncertainty is statistical and the second systematic. Table_4.pdf [44 KiB] HiDef png [176 KiB] Thumbnail [92 KiB] tex code Forward-backward ratios,$R_{\rm FB}$, of$ B ^+ $,$ B ^0$and$\Lambda ^0_ b $production in bins of$ p_{\mathrm{T}}$and integrated over$2.5<|y|<3.5$. The first uncertainty is statistical and the second systematic. Table_5.pdf [42 KiB] HiDef png [76 KiB] Thumbnail [40 KiB] tex code Ratios of nuclear modification factors,$R^{\Lambda ^0_ b / B ^0 }_{ p\mkern 1mu\mathrm{Pb} }$, in bins of$ p_{\mathrm{T}}$and integrated over$2.5<|y|<3.5$, for$ p\mkern 1mu\mathrm{Pb} $and$\mathrm{Pb}\mkern 1.5mu p $samples. The first uncertainty is statistical and the second systematic. Table_6.pdf [35 KiB] HiDef png [91 KiB] Thumbnail [48 KiB] tex code Nuclear modification factor,$R_{ p\mkern 1mu\mathrm{Pb} }$, of$ B ^+ $production in$ p\mkern 1mu\mathrm{Pb} $and$\mathrm{Pb}\mkern 1.5mu p $collisions, in bins of$ p_{\mathrm{T}}$for the range$2.5<|y|<3.5\$. The first uncertainty is statistical and the second systematic. Table_7.pdf [35 KiB] HiDef png [93 KiB] Thumbnail [48 KiB] tex code
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https://bugs.php.net/bug.php?id=47324 | php.net | support | documentation | report a bug | advanced search | search howto | statistics | random bug | login go to bug id or search bugs for
Bug #47324 still not working after trying most versions
Submitted: 2009-02-06 04:43 UTC Modified: 2009-08-19 07:44 UTC
Votes: 2 5.0 ± 0.0 2 of 2 (100.0%) 0 (0.0%) 0 (0.0%)
From: kmteoh at hotmail dot com Assigned: pajoye (profile)
Status: Closed Package: Zip Related
PHP Version: 5.2.9RC1 OS: win32 only -w2k
Private report: No CVE-ID: None
[2009-02-06 04:43 UTC] kmteoh at hotmail dot com
Description:
------------
can't get the ziparchive to add files correctly. tried different version of php_zip.dll same thing happen, and it generates funny files. followed instructions in #46985, used php_zip.dll version 5.2.5.5, 5.2.8.8, 5.2.9.9 all not work. it only work in cli but not browser (isapi). it generates files like test.zip.b03252 and test.zip.a03252 for me instead of actual test.zip. i renamed to test.zip then tried to extract but crc error.
Reproduce code:
---------------
<?php
$zip = new ZipArchive; if ($zip->open('test.zip') === TRUE) {
$zip->addFile('index.txt', 'newname.txt');$zip->close();
echo 'ok';
} else {
echo 'failed';
}
?>
Expected result:
----------------
should be able to open the test.zip with winzip or winrar easily
Actual result:
--------------
crc error.
## Pull Requests
Add a Pull Request
## History
[2009-02-06 08:29 UTC] pajoye@php.net
Please try using this CVS snapshot:
http://snaps.php.net/php5.2-latest.tar.gz
For Windows:
http://windows.php.net/snapshots/
[2009-02-06 08:30 UTC] pajoye@php.net
And be sure to actually use the correct extension dir.
[2009-02-09 04:53 UTC] kmteoh at hotmail dot com
extension dir is definitely correct. the same script worked in cli but not browser (isapi). tried http://snaps.php.net/php5.2-latest.tar.gz
still no luck. i ended up using system() with external rar.exe and unrar.exe to do the job which is perfect. though certain system setup will not allow system() or exec() due to permission settings, which is why i am keen to have my product coded with php internal lib rather than using external tools.
[2009-02-25 14:55 UTC] pajoye@php.net
please provide a link to the file you are adding.
Also the windows files are in http://windows.php.net/snapshots/
[2009-02-25 15:00 UTC] pajoye@php.net
Other question, are you sure you are creating a fresh new archive and not opening an already corrupted archive?
Try:
if ($zip->open('test.zip', ZIPARCHIVE::CREATE) === TRUE)... (create a new one but does not overwrite an existing archive) or if ($zip->open('test.zip', ZIPARCHIVE::OVERWRITE) === TRUE)..
[2009-03-01 22:36 UTC] kmteoh at hotmail dot com
i have tried CREATE and OVERWRITE options. both don't work. this is the file of creating brand new zip file using isapi.
http://www.mingspc.com/mingspc/t.zip
in the file you can also find 2 files with fileext 03252 which was generated upon the script runs.
found a good script from phpclasses.org by Rochak Chauhan works pretty well, he was using crc32() gzcompress() to do the job. hope this help.
[2009-03-02 15:46 UTC] pajoye@php.net
I need the script you use to create this archive AND the original files you add to the archives. To show me the corrupted archive is not enough.
[2009-03-02 21:27 UTC] kmteoh at hotmail dot com
http://www.mingspc.com/mingspc/source.zip
here is the source code. the script i was using are all from php.net anyway
[2009-03-02 21:33 UTC] pajoye@php.net
Where are the files that you are actually adding to the archive?
All I see is a normal script and nothing but tempory (and corrupted) files created by the zip extensions, for example t.zip.a03252.
Or are you trying to create t.zip in the \testscript\ directory using the content of \testscript\? That would be bad :)
[2009-03-02 21:39 UTC] kmteoh at hotmail dot com
"Or are you trying to create t.zip in the \testscript\ directory using
the content of \testscript\? That would be bad :)"
i was actually trying to create new zip file in the folder i store my source file and source code (i was treating the zip.php is the file i want to add into archive) is that what causing all problem?
[2009-03-02 21:46 UTC] pajoye@php.net
Yes, as it tries to add the temporary files as well (recursive additions so to say).
Can you try to create the archive in a complete different path:
c:\www\foo\t.zip
and add the content of
c:\www\bar\
for example.
[2009-03-02 22:15 UTC] kmteoh at hotmail dot com
$path = 'C:\\inetpub\\wwwroot\\teohm\\gus\\'; //files to add in archive$file = 'C:\\inetpub\\wwwroot\\teohm\\gus.zip'; //target
$zip = new ZipArchive(); if (($zip->open($file, ZipArchive::CREATE)) === TRUE) { archive($path, null); //same function as previous attachment
$zip->close(); } i see gus.zip.a03932 and gus.zip.b03932 in "C:\\inetpub\\wwwroot\\teohm\\" still not working :( [2009-03-02 22:45 UTC] pajoye@php.net ok, I still need the files you are adding to debug this problem. But it works here, IIS5/6/7 ISAPI or FastCGI. [2009-03-28 15:03 UTC] ivan3k-sc1 at yahoo dot com dot ar I have the same problem trying to add a file, no mather its location. Other files are ok. this is the content of the file ------------------------------- <? require_once("inc/core.php"); restore_error_handler(); ?> <hr> <?$db = Db::getDbConnection();?>
Probando Conexi?n a BD: <?=($db->IsConnected() ? "OK" : "ERROR");?> <hr> -------------------------------- [2009-03-28 15:51 UTC] pajoye@php.net I've really no idea yet what's wrong. We have made some bug fixes lately, can you try again a 5.2/5.3 snapshot please? [2009-04-05 01:00 UTC] php-bugs at lists dot php dot net No feedback was provided for this bug for over a week, so it is being suspended automatically. If you are able to provide the information that was originally requested, please do so and change the status of the bug back to "Open". [2009-08-19 07:22 UTC] jw328 at gmail dot com Exactly the same issue - I suspect its environment related. Mine is: IIS6, Win2003, Isapi from 5.2.8. Have tried php_zip.dll from 5.2.8 and 5.2.10 - both are v1.8.11 and siplay the same behaviour. Same issue looks as though its been occurring since 2006. Couldn't get simpler code to reproduce (invoked from browser): error_reporting(E_ALL); unlink("./a.zip");$zip = new ZipArchive();
$filename = "./a.zip"; if (!$zip->open($filename, ZIPARCHIVE::CREATE)) { exit("cannot open <$filename>\n");
} else {
echo "file <$filename> OK\n"; }$zip->addFromString("ma.txt", "0123456789");
var_dump($zip->close()); var_dump($zip);
Having wasted the day on this I will use another library/exe.
[2009-08-19 07:44 UTC] pajoye@php.net
Keep waste days if you don't use recent versions.
The bug has been fixed month ago.
[2010-08-26 21:37 UTC] selosindis at gmail dot com
I noticed this bug was closed a long time ago, yet the examples from php.net
(listed here) are still not working.
There was no actual resolution posted here (that I could see), so if it is in
fact fixed, could you please explain the process to get it working?
I'm running php 5.2.9 and the latest version of ZipArchive.
The files always end up with "zipName.zip.39u525" or something similar.
Thanks for your help!
~Scott
Copyright © 2001-2020 The PHP Group All rights reserved. Last updated: Mon Aug 10 15:01:25 2020 UTC | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.36958181858062744, "perplexity": 13245.740518267226}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.3, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2020-34/segments/1596439736057.87/warc/CC-MAIN-20200810145103-20200810175103-00000.warc.gz"} |
http://link.springer.com/article/10.1007/s10946-013-9341-z | , Volume 34, Issue 2, pp 185-191
Date: 01 May 2013
Effect of Grating Spacing on Response Time and Sensitivity in Photorefractive Materials at Large Modulation Depth
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Abstract
Photorefractive response time and photorefractive sensitivity are two important parameters characterizing photorefractive materials. We study theoretically the effect of the grating spacing on these parameters at large modulation depth in the absence and presence of an applied electric field for some of the most promising photorefractive materials, namely, LiNbO3, KNSBN, SPS, BGO, and GaAs. We find that the response time increases with increasing grating spacing for LiNbO3 and KNSBN, whereas the response time decreases with increasing grating spacing for SPS, BGO, and GaAs. The photorefractive sensitivity is mainly affected by the mobility–lifetime product in the presence of an applied electric field. | {"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9144395589828491, "perplexity": 2572.3611629340903}, "config": {"markdown_headings": false, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2014-35/segments/1408500826679.55/warc/CC-MAIN-20140820021346-00271-ip-10-180-136-8.ec2.internal.warc.gz"} |
https://www.dcode.fr/combinations-with-repetitions | Search for a tool
Combinations with Repetition
Tool to generate combinations with repetitions. In Mathematics, a combination with repetitions is a combinations of items which can be repeated.
Results
Combinations with Repetition -
Tag(s) : Combinatorics, Mathematics
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# Combinations with Repetition
## Counting Combinations with Repetitions
Tool to generate combinations with repetitions. In Mathematics, a combination with repetitions is a combinations of items which can be repeated.
### How to generate combinations with repetition?
Item combinations with repetition consist in the list of all possible arrangements of elements (which can be repeated) in any order.
Example: A,B,C items be shuffled in 6 couples of 2 items: A,A A,B A,C B,B B,C, C,C. Without repetition, there would be only 3 couples A,B, A,C et B,C.
The sets of n elements are called tuples: {1,2} or {1,2,3} are tuples.
### How to count combinations with repetition?
Counting repeated combinations of k items (sometimes called k-combination) in a list of N is noted $$\Gamma_n^k$$ and $$\Gamma_n^k = {n+k-1 \choose k} = \frac{(n+k-1)!}{k! (n-1)!}$$
The number of combinations with repeats of $$k$$ items among $$N$$ is equal to the number of combinations without repeats of $$k$$ items among $$N + k - 1$$.
### How to remove the limit when computing combinations?
The calculation of the combinations generates an exponential number of values which require large calculation servers, generations have therefore a cost. | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 2, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.4171825349330902, "perplexity": 1561.533805650063}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2018-09/segments/1518891813571.24/warc/CC-MAIN-20180221063956-20180221083956-00677.warc.gz"} |
https://ch.gateoverflow.in/420/gate-chemical-2016-question-28 | The model $y=mx^{2}$ is to be fit to the data given below.
$$\begin{array}{|cl|cI|}\hline &{x} & {1} & {\sqrt{2}} & {\sqrt{3}} \\ \hline &{y} & {2} & {5} & {8} \\ \hline \end{array}$$
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http://www.chegg.com/homework-help/questions-and-answers/plate-carries-charge-4-c-rod-carries-charge-150-c-electrons-transferred-plate-rod-objects--q1157316 | ## Electric Forces and Electric Fields
A plate carries a charge of -4 µC, while a rod carries a charge of 1.50 µC. How many electrons must be transferred from the plate to the rod, so that both objects have the same charge? | {"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9285109043121338, "perplexity": 724.9395431501365}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2013-20/segments/1368706964363/warc/CC-MAIN-20130516122244-00027-ip-10-60-113-184.ec2.internal.warc.gz"} |
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Open Access 21-04-2021 | Empirical Research
The Co-development of Friends’ Delinquency with Adolescents’ Delinquency and Short-term Mindsets: The Moderating Role of Co-Offending
Auteurs: Ivy N. Defoe, Jean-Louis van Gelder, Denis Ribeaud, Manuel Eisner
Gepubliceerd in: Journal of Youth and Adolescence | Uitgave 8/2021
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Abstract
The companions in crime hypothesis suggests that co-offending moderates the link between peer delinquency and adolescent delinquency. However, this hypothesis has rarely been investigated longitudinally. Hence, this study investigated the co-development of friends’ delinquency and adolescents’ delinquency, as well as the co-development of friends’ delinquency and short-term mindsets (impulsivity and lack of school future orientation). Whether this co-development is stronger when adolescents engage in co-offending was also investigated. Three data waves with two year lags from an ethnically-diverse adolescent sample (at wave 1: N = 1365; 48.6% female; Mage = 13.67; age range = 12.33–15.09 years) in Switzerland were used. The results from parallel process latent growth modeling showed that the co-development between friends’ delinquency and adolescents’ delinquency was stronger when adolescents engaged in co-offending. Thus co-offending likely provides direct access to a setting in which adolescents continue to model the delinquency they learned with their peers.
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Introduction
Peer affiliation and, in return, “peer influence” are regarded as hallmarks of adolescence (Brechwald and Prinstein 2011). Indeed, the finding that delinquency of peers predicts adolescent delinquency has been consistently replicated (Brechwald and Prinstein 2011). However, it has rarely been investigated whether delinquency of peers is also associated with other correlates of delinquency such as short-term mindsets (e.g., impulsivity and lack of future orientation). Furthermore, it is often presumed that delinquent peer affiliation implies that adolescents are also committing delinquency together with their peers (i.e., co-offending) (Brechwald and Prinstein 2011; Warr 2002). In fact, some theorists posit that engaging in delinquency with peers is a primary mechanism that causes the progression of delinquency during adolescence (Warr 2002). It can be extrapolated from this hypothesis that co-offending moderates the link between peer delinquency and adolescent delinquency. Yet, co-offending is rarely measured directly in the (developmental) psychology literature, and longitudinal studies that directly measure this concept in the criminological literature are also uncommon (cf Goldweber et al. 2011). As a result, longitudinal studies are virtually non-existent on whether co-offending indeed plays a moderating role in the relationship between delinquency on the one hand and delinquency of peers and short-term mindsets on the other hand. To this end, drawing upon the companions in crime hypothesis (Warr 2002), differential association theory (Sutherland 1947) and the psychosocial maturity hypothesis (Steinberg et al. 2009), the current longitudinal study investigates whether the co-development of (non-)best friends’ delinquency with adolescents’ delinquency and short-term mindsets (impulsivity and lack of school future orientation) are stronger when adolescents engage in co-offending with their friends.
Co-development of Friends’ Delinquency and Adolescent Delinquency
The peer context becomes increasingly important for adolescents. In addition to close (smaller in size) friendships with best friends, individuals interactions with peers also occur in cliques, crowds, and larger networks of friends (Brechwald and Prinstein 2011). Research is currently mixed on the influences of best-friends versus such ancillary friends (i.e., non-best friends; Rees and Pogarsky 2011). Adolescents tend to overestimate the similarity between their own behavior and the behavior of their friends’ behavior when perceptual measures of peer delinquency are used (Rees and Greg Pogarsky 2011). Nevertheless, when accounting for measurement issues (e.g., the use of perceptual measures), “peer influence” on delinquent behavior has been shown to be paramount, as it can occur in comparable ways within adolescents’ interactions with delinquent best friends versus delinquent ancillary friends (Rees and Greg Pogarsky 2011).
When (delinquent) peers interact, co-offending can be the result, especially during adolescence (for an overview see: Warr 2002). Research on such delinquent peer influence suggests that it need not exclusively occur within (best) friend relationships, as it is common in broader peer networks as well (Brechwald and Prinstein 2011; Rees and Pogarsky 2011). Moreover, co-offending with delinquent peers has been theorized to link delinquent peer affiliation to adolescent delinquency (Dynes et al. 2015). Scholars have even proposed that “the age distribution of crime, stems from age related changes in peer relations” (p. 99; Warr 2002; but see Stolzenberg and D’Alessio 2008). This assumption has more recently been referred to as the “companions in crime hypothesis” (see Stolzenberg and D’Alessio 2008). This hypothesis suggests that peer influence during co-offending is a mechanism that causes the progression of delinquency during adolescence. For example, adolescents tend to imitate each other’s delinquency (Piquero and Moffitt 2010), and this effect can be even stronger when they are in company of each other while engaging in delinquency.
Although developmental theories and longitudinal research on co-offending is limited (cf. Goldweber et al. 2011), some criminological theories on social learning explicitly hypothesize that co-offending is associated with the onset, persistence and desistance of delinquency (Piquero et al. 2007). For instance, it is presumed that co-offending provides a setting wherein peers can directly influence each other and promote increasing levels of delinquency (Dynes et al. 2015). Individuals who co-offend might also be more susceptible to delinquent peer norms (Dynes et al. 2015). This assertion is in line with one of the propositions of differential association theory, which hypothesizes that that interactions with delinquent peers facilitate the learning of criminal techniques (Dynes et al. 2015; Sutherland 1947). Hence, it is assumed that this transmission of criminal techniques will be stronger if individuals are in the presence of each other during the engagement in delinquency (i.e., co-offending), versus whether individuals merely affiliate with delinquent peers (e.g., Dynes et al. 2015). Such co-offending could also be a result of peer group conformity (Asch 1951), and it may even influence (subsequent) delinquent behavior in the long-term. Taken together, it stands to reason that the influence of peer delinquency could be stronger for adolescents who co-offend compared to solo-offenders who merely have delinquent peers but do not co-offend with them. However, studies that could address this question are presently lacking (cf., Dynes et al. 2015), particularly because studies that assess delinquent peer affiliation do not specifically assess co-offending (cf. Dynes et al. 2015; McGloin and Stickle 2011).
Nevertheless, at least two cross-sectional studies based on court-involved youth have investigated related questions. One of those studies found that the link between friends’ delinquency and adolescent delinquency only existed for adolescents who actually co-offend with their peers (Dynes et al. 2015). Additionally, the second study reported that compared to other offenders, chronic offenders were less likely to mention “peer influence” as a reason for engaging in delinquency (McGloin and Stickle 2011). However, these two offender groups were equally likely to engage in co-offending with peers (McGloin and Stickle 2011). It was thus concluded that although chronic offenders are less likely to engage in delinquency because of their peers, they are still just as likely to engage in co-offending (McGloin and Stickle 2011). These results suggest that delinquency of peers does not necessarily have to imply that adolescents are engaging in delinquency with their peers, and that delinquency with peers can moderate the link between peer delinquency and adolescent delinquency. Building on these two cross-sectional studies on court-involved youth, an important aim of the current study is to use a longitudinal design to establish whether there is co-development among adolescents’ delinquency and best friends’ delinquency in a community sample. Furthermore, the current study uniquely examines whether this hypothesized co-development is stronger when adolescents co-offend with their friends. These hypotheses are in line with the companions in crime hypothesis (Warr 2002).
Co-development of Friends’ Delinquency and Short-term Mindsets
The psychosocial maturity hypothesis suggests that influence of peers on (deviant) behaviors, and indicators of short-term mindsets (e.g., impulsivity, lack future orientation), all show significant and similar non-linear development particularly during adolescence, with these behaviors peaking during mid-adolescence (Steinberg, 2008; Steinberg et al. 2009; but see e.g., Chen 2009; Duell et al. 2016). Extrapolating from this notion, the current study pioneers a test of whether the mere delinquency of best friends is developmentally interrelated with impulsivity and lack of school future orientation during adolescence, and whether this is particularly the case when adolescents engage in delinquency together. This hypothesis also aligns with differential association theory on transmission of attitudes and beliefs (Sutherland 1947; but see Hochstetler et al. 2002). Namely, exposure to values and beliefs about violation of the law via delinquent peers could promote short-term mindsets such as impulsivity and lack of future orientation. This hypothesis is important to investigate, because if peer delinquency and short-term mindsets show such co-development, this could imply that peer delinquency is related to adolescent delinquency because it contributes to the development of short-term mindsets in youth. As such, short-term mindsets could be the conduit through which the association between peer delinquency and adolescent delinquency develops over time. Essentially, adolescents may adapt their own attitudes from observing the impulsive and risky behavior of their delinquent peers, for example by hearing them talk about taking risks and disregarding the future (Meldrum et al. 2012).
Co-offending (i.e., being present and thus observing others engaging in delinquency) could likely also make the association between delinquency of peers and short-term mindsets stronger. Specifically, co-offending could lead adolescents to conclude that they must be impulsive individuals who do not care about the future—and this could thus encourage the development of short-term mindsets. As such, it is further conceivable that co-offending would exacerbate the link between delinquency of peers and adolescent delinquency, which the current study explicitly investigates. These assertions overlap with the three hypotheses mentioned earlier, namely, companions in crime hypothesis, psychosocial maturity hypothesis, and differential association theory. Then again, of note is that other scholars (Hochstetler et al. 2002) have been more critical of such assertions related to differential association which posits that crime-condoning tendencies are transmitted during co-offending. It has for example been argued that although interactions with delinquent peers during co-offending have shown to exacerbate delinquency, this is not because of increases in crime-condoning attitudes (Hochstetler et al. 2002). Namely, empirical research demonstrated that crime-condoning attitudes do not appear to be the mechanism that links delinquent peer influences into solo-offending or co-offending, which questions whether group influences such as co-offending is the mechanism of differential association (Hochstetler et al. 2002). However, a search of the current literature did not result in any studies that have explicitly investigated this implied interaction between delinquency of peers and co-offending in the prediction of crime-condoning tendencies such as impulsivity and lack of future orientation. Nevertheless, three longitudinal studies were located that investigated whether an indicator of peer delinquency is longitudinally associated with levels of impulsivity, or self-control, more broadly.
The final relevant study did assess co-offending, although it did not explore it as a moderator (Goldweber et al. 2011; see also Ashton et al. 2020). Via trajectory group modeling among a sample of serious male adolescent offenders, it was demonstrated that the group which increasingly engaged in co-offending showed less psychosocial maturity (i.e., more short-term mindsets) versus the occasional/mixed solo-offenders and the exclusively solo offenders from age 14 to 17. Those results show support for psychosocial maturity hypothesis and differential association theory. The current study extends the aforementioned study (Goldweber et al. 2011) in various ways. First, in addition to including a measurement of co-offending, the present study simultaneously investigates whether mere delinquency of best friends also predicts short-term mindsets and whether this is dependent on whether adolescents are actually engaging in co-offending with their friends. That is, whether co-offending (versus non co-offending) serves as a moderator in the co-development between delinquency of best friends and short-term mindsets is investigated. Secondly, instead of using one measurement wave of short-term mindsets and group trajectory modeling, the present study uses three measurement waves of both short-term-mindsets and friends’ delinquency. This is achieved via parallel LGMs in order to investigate whether the development of these constructs show correlated change (i.e., co-development) over three waves. Thirdly, the current research questions are examined using a community sample as opposed to a clinical sample (see Goldweber et al. 2011).
Finally, unlike the similar abovementioned study (Goldweber et al. 2011), the current study takes well-established correlated risk factors of delinquency into account. For example, it has consistently been demonstrated that demographic factors such as gender and ethnicity are strong correlates of crime, namely males and ethnic minorities are over-represented in the juvenile justice system (for a review see: Piquero et al. 2015). Additionally, an extensive review of longitudinal studies found that socioeconomic factors, such as low family income (which is intertwined with parental occupation) as well as youth’s own school achievement are among the strongest predictors of juvenile delinquency (Murray and Farrington 2010). These important correlates will be controlled for in the current study.
Current Study
Extrapolating from the companions in crime hypothesis, social learning theories (e.g., differential association theory) and the psychosocial maturity hypothesis and empirical studies (e.g., Dynes et al. 2015), it is to be expected that peer delinquency on the one hand shows co-development with adolescent delinquency and short-term mindsets on the other. This co-development is expected to be stronger when adolescents engage in co-offending. However, to date, there is a dearth of longitudinal studies that have investigated these hypotheses, and longitudinal studies on whether co-offending indeed plays a moderating role in the above-mentioned co-development links are virtually non-existent. The current study tests these research questions using three waves of longitudinal data from an ethnically-diverse Swiss community sample of adolescents, while controlling for ethnicity, gender, educational track, and socioeconomic status. The main hypothesis is that co-development of best friends’ delinquency with adolescent delinquency and short-term mindsets will exist and that these links will be stronger for youth who engage in co-offending.
Methods
Participants
The adolescents in the current study are participants in an 8-wave ongoing longitudinal-intervention study: “Zurich Project on the Social Development from Childhood into Adulthood (z-proso)”, which began in 2004, in Switzerland (Eisner et al. 2011). The data-collections took place every two years. In total, 1675 first graders (Mage = 7.45, SD = 0.39; 48% female) from 56 randomly selected schools formed the target sample at baseline (W1) (Van Gelder et al. 2015). Of these participants, 46% of both parents were not born in Switzerland (Van Gelder et al. 2015). Further detailed demographic information is reported in “Eisner et al. (2011)”. The current study is based on waves W5 to W7, because these waves overlap with the adolescence period, and because data on the main variables of interest were consistently collected across these waves. Accordingly, henceforth, W5 will be referred to as baseline (i.e., T1; N = 1365; 48.6% female). For W5 and W6, passive parental consent along with active informed participant consent (W5–W6) was obtained, whereas for W7 only active informed participant consent was obtained. From T1–T3, 82, 86, and 78% of the adolescents from the original target sample participated, respectively. The average ages were 13.67, 15.44, and 17.45 years from T1–T3, respectively. Paper questionnaires were filled out during leisure time in classroom-settings. Participants received an incentive worth the equivalent of US$30, US$50, and US\$60 from T1–T3, respectively.
Measures
Impulsivity
Participants reported on two items on the “impulsivity subscale” of an adjusted and abbreviated Self-control Scale of Grasmick et al. (1993) (Ribeaud and Eisner 2006). The items were: (1) I often act on the spur of the moment without stopping to think and (2) I often do whatever brings me pleasure here and now, even at the cost of some distant goal. Answer categories ranged from “fully untrue” (=1) to “fully true” (=4). This sub-scale has been validated in previous studies (Van Gelder et al. 2018, 2020). Mean scores were computed from the items on the scale. The Cronbach’s Alpha is biased towards scales with few items, hence the mean inter-item correlations is opted for to evaluate reliability. These mean inter-item correlations were 0.273, 0.275, 0.332 from T1–T3, respectively, which denotes adequate reliability (see Clark and Watson 1995).
School Future Orientation
Participants reported on the following three statements concerning school future orientation in the /school domain: (1) When I grow up I want to have an interesting job, and I’m doing everything now to work towards that goal, (2) I try hard at to have a good job later in life and (3) Doing well at is important to me. Answer categories ranged from “fully untrue” (=1) to “fully true” (=4) (Van Gelder et al. 2018). Mean scores were computed. The mean inter-item correlations were adequate (r = 0.472, 0.524, and 0.494, from T1–T3 respectively).
Delinquency
Participants reported on their engagement in 14 different delinquent behaviors within the past-12-months via a delinquency questionnaire adjusted from Wetzels et al. (2001). Items included both minor delinquency (graffitiing, vandalism) and more serious forms of delinquency (e.g., robbery, assault). Mean scores were computed from the yes/no responses on these items. Cronbach alphas were 0.774, 0.757, and 0.710 across T1–T3, respectively, indicating adequate reliability.
Delinquency of Friends
Participants were asked to answer the following questions about each of their two best friends: (1) in the last year, has he/she purposely hit or kicked another adolescent and injured them in the process? and (2) in the last year, has he/she stolen something from a shop, kiosk, or shopping mall? From the yes/no responses, the mean scale score of each best friend, was combined into one overall mean score that represented an average delinquency score of the adolescent’s two best friends. The mean inter-item correlations were 0.329, 0.257, 0.265 across T1–T3, denoting adequate reliability. However, of note is that the current reports of friends’ delinquency are based on a “perceptual measure” of best-friends’ delinquency. That is, the best friend is not reporting on his/her own delinquency. Nevertheless, since best friends form close companionships (versus individuals in the broader peer network), it is assumed that adolescent’s evaluations of their best-friends behavior are reliable (Rees and Pogarsky 2011).
Co-offending with Friends
Participants reported whether they ever engage in the following together with their friends: (1) meet up with friends and have fights with other adolescents, and (2) meet up with friends and together steal something from a shop or kiosk. Answer categories ranged from: “never” (=1) to “(almost) every day” (=6). Mean scores were computed, and the inter-item correlations showed adequate reliability: 435, 0.338, 0.402 from T1–T3 respectively.
Additionally a categorical variable that depicted 0 = “non co-offending group” (i.e., individuals who do not have experience with co-offending across all the three waves of the study) and 1 = “co-offending group” (i.e., individuals who have experience with co-offending at least 1 time across the 3 waves) was computed. This categorical variable was used in the multi-group analyses to investigate whether experience with co-offending serves as a moderator in the current study (see the strategy of analyses).
Control Variables
Gender (“0” for females and “1” for males), ethnicity (“0” = at least one parent born in Switzerland; “1” = two foreign-born parents), socio-economic status (SES) and educational track were included the parallel process LGM’s as control variables. The highest International Occupational Status (ISEI) score (Ganzeboom et al. 1992) of the two caregivers was used as an indicator of SES. Educational track at T1 included the following categories: 0 = special needs or primary school (e.g., participants who repeated (a) grade(s) in primary school); 1 = tracks leading to “blue-collar” apprenticeship (“Sekundarschule B/C”); 2 = tracks leading to “white-collar” apprenticeship (“Sekundarschule A”); 3 = tracks leading to university (“Mittelschule/Gymnasium”, i.e., A-levels equivalents).
Strategy of Analyses
To model interrelations between individuals’ developmental trajectories for the constructs of interest over time, parallel process LGM’s in Mplus 8 were used. (Muthén and Muthén, 19982017). Using this methodology, an “intercept” (an individual’s initial or baseline level on a construct), and the slope (an individual’s rate and direction of change, i.e., their growth/development for a construct) are identified. Together these “growth factors” determine the level and shape of the developmental trajectories (Bollen and Curran 2006).
In a second preliminary step, the AIC and Sample-size Adjusted Bayesian Information Criterion (SABIC; Akaike 1987; Sclove 1987) were used to compare the fit between the abovementioned linear and the unspecified non-linear univariate LGM’s. Subsequently, the best fitting model was retained for the main parallel process LGM analyses (Bollen and Curran 2006). Finally, in the parallel process LGM’s, baseline levels of gender, SES, educational track, and ethnicity were controlled for by including these variables in the model as predictors of the growth factors.
In sum, a total of three parallel process LGM’s with multi-groups (categorical moderation models) were estimated: (1) co-development between friends’ delinquency and adolescents’ delinquency for non co-offenders versus co-offenders, (2) co-development between friends’ delinquency and impulsivity for non co-offenders versus co-offenders, and (3) co-development between friends’ delinquency and school future orientation for non co-offenders versus co-offenders. Each model tested whether the slopes were correlated (i.e., “correlated change”) for the constructs of interest, as well as whether the intercepts were correlated. A Wald-test was used for the multi-group models to determine whether co-offending moderated the hypothesized co-development between adolescent delinquency and delinquency of friends, and the co-development between short-term mindsets (impulsivity and lack of school future orientation) and delinquency of friends. However, the final above-mentioned school future orientation model ran into convergence issues, and thus a similar alternative parallel LGM model was run, but without the use of a multi-group analyses. This model estimated whether the developmental trajectories (slopes) of school future orientation and delinquency of friends were correlated, as well as whether the developmental trajectories of school future orientation and co-offending were correlated. Via a Wald-test, the correlation between the slopes of school future orientation and delinquency of friends was compared to the correlation between the slopes of school future orientation and co-offending. Full maximum likelihood (FIML) estimation in Mplus, which allowed for the inclusion of variables with missing cases in the analyses (Muthén and Muthén, 19982017). There was a minimum of 13.7% missing data and a maximum of 31% missing data for the main variables of interest. Additionally, robust procedures (MLR) (Satorra and Bentler 1994) were employed to deal with potential non-normality. Finally, considering the large sample size, a stringent p-value of p < 0.01 was used.
Results
Descriptive Statistics
Tables 1 and 2 display the descriptive statistics and the correlations between the variables of interest. All variables were significantly correlated in the anticipated directions.
Table 1
Descriptive statistics of the variables of interest
T1 Impuls
T2 Impuls
T3 Impuls
T1 SFO
T2 SFO
T3 SFO
T1 Co-off
T2 Del Co-off
T3 Del Co-off
T1 Del Friend
T2 Del Friend
T3 Del Friend
T1 Del
T2 Del
T3 Del
Mean
2.296
2.370
2.335
3.236
3.160
3.161
1.225
1.400
1.086
0.102
0.102
0.082
0.070
0.081
0.071
SD
0.618
0.567
0.600
0.612
0.614
0.596
0.664
0.465
0.390
0.212
0.202
0.186
0.126
0.132
0.116
Min
1.00
1.00
1.00
1.00
1.00
1.00
1.00
1.00
1.00
0.00
0.00
0.00
0.00
0.00
0.00
Max
4.00
4.00
4.00
4.00
4.00
4.00
6.00
5.00
5.50
1.00
1.00
1.00
1.00
1.00
0.86
SFO school future orientation, co-off co-offending, Impuls impulsivity, Del delinquency, Del friend delinquency of friends, Min minimum, Max maximum
Table 2
Correlations between variables of interest
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
1. T1 Impulsivity
2. T2 Impulsivity
0.295**
3. T3 Impulsivity
0.235**
0.390**
4. T1 SFO
−0.240**
−0.129**
−0.129**
5. T2 SFO
−0.153**
−0.215**
−0.153**
0.432**
6. T3 SFO
−0.144**
−0.136**
−0.253**
0.364**
0.459**
7. T1 Co-offending
0.143**
0.105**
0.079**
−0.217**
−0.081**
−0.029
8. T2 Co-offending
0.052
0.111**
0.072*
−0.139**
−0.138**
−0.069*
0.406**
9. T3 Co-offending
−0.003
0.080**
0.068*
−0.097**
−0.040
−0.092**
0.271**
0.447**
10. T1 Del of friend
0.154**
0.100**
0.086**
−0.188**
−0.113**
−0.115**
0.236**
0.175**
0.091**
11. T2 Del of friend
0.088**
0.096**
0.131**
−0.145**
−0.182**
−0.166**
0.172**
0.310**
0.118**
0.361**
12. T3 Del of friend
0.120**
0.120**
0.126**
−0.124**
−0.132**
−0.180**
0.123**
0.150**
0.199**
0.237**
0.358**
13. T1 Del
0.247**
0.142**
0.141**
−0.252**
−0.126**
−0.139**
0.410**
0.223**
0.110**
0.477**
0.288**
0.235**
14. T2 Del
0.206**
0.249**
0.171**
−0.228**
−0.251**
−0.185**
0.273**
0.312**
0.180**
0.346**
0.407**
0.304**
0.568**
15. T3 Del
0.181**
0.171**
0.218**
−0.180**
−0.196**
−0.260**
0.186**
0.178**
0.218**
0.232**
0.298**
0.485**
0.426**
0.593**
Del delinquency, Del of friend delinquency of friends, SFO school future orientation
*p < 0.05; **p < 0.01
Univariate LGMs
With the exception of the co-offending model, the non-linear models fitted better than the linear models (see Tables 3 and 4, and Fig. 2). Of note, the fit of the linear versus non-linear model of co-offending as indicated by the AIC showed negligible differences, and according to the SABIC, the linear model fitted better. Hence the linear model was retained, and it showed an excellent fit (whereas the non-linear model was just-identified).
Table 3
Model fit comparisons to determine the best-fitting univariate LGM models
Model
AIC
SABIC
Impulsivity
Linear
7032.594
7049.590
Non-Linear
7024.768
7041.764
School future orientation
Linear
6792.801
6809.796
Non-Linear
6790.316
6809.436
Delinquency
Intercept only
−6463.563
−6452.941
Linear
−6524.779
−6507.783
Non-Linear
−6525.553
−6508.558
Co-offending
Linear
5708.843
5725.833
Non-Linear
5708.319
5727.433
Delinquency of friends
Linear
−1775.907
−1758.987
Non-Linear
−1779.058
−1762.138
The non-linear models of impulsivity, delinquency and delinquency of friends had a negative residual variance, which were thus constrained to zero (Muthén and Muthén, 19982017) to resolve estimation issues
Table 4
LGM Results and Model fit for the univariate best-fitting models
Measure
Intercept (variance)
(Non-)linear slope (variance)
Correlation intercept- (non-)linear slope
Chi-square (df)
CFI
TLI
RMSEA
SRMR
Impulsivity
2.297*** (0.382***)
0.059** (0.342***)
−0.814***
4.789a p = 0.029
0.986
0.959
0.051
0.013
School Future Orientation
3.235*** (0.364)
−0.085*** (0.279)
−0.734*
0(0) p < 0.001
1
1
0
0
0.071*** (0.016***)
0.003 (0.013***)
−0.646**
13.658a p < 0.001
0.956
0.867
0.092
0.021
Delinquency of Friends
0.104*** (0.017***)
−0.020** (0.032***)
−0.294**
0.319a p = 0.573
1
1.013
0
0.004
Co-offending
1.217*** (0.114**)
−0.065*** (0.012)
−0.818***
2.216a p = 0.137
0.971
0.913
0.029
0.012
*p < 0.05; **p < 0.01; ***p < 0.001
aThe non-linear model of future orientation was just-identified
Altogether, the results revealed that the co-offending model showed steady declines on average from T1 to T3. However, the delinquency of friends model began to level off between T1 and T2, and declined from T2 to wave T3. Thus overall there were non-linear declines on average from T1 to T3 for delinquency of friends. The delinquency of friends models showed significant variance around the intercept and slope. However, the co-offending model only showed significant variance for the intercept, but not for the slope. This indicates that whereas participants varied in their initial levels of co-offending, on average participants declined in co-offending at a similar pace.
Impulsivity showed non-linear increases from T1 to T3, as it increased from T1 to T2, and began to level off from T2 to T3. School future orientation showed the opposite pattern. That is, overall there were non-linear declines on average from T1 to T3. More specifically, it decreased from T1 to T2 and began to level off between T2 to T3. Considering the results of impulsivity and future orientation in conjunction, short-term mindsets can be said to peak at T2 (i.e., mid-adolescence) and level off thereafter. Additionally, whereas impulsivity had significant intercept and slope variance, this was not the case for school future orientation.
Finally, whereas on average adolescent delinquency remained stable throughout adolescence, there was significant intercept and slope variance. This suggests that some adolescents had upward/increasing slopes (i.e., positive slopes) in delinquency, whereas others had downward/decreasing slopes (i.e., negative slopes) in delinquency. An “intercept only model” for adolescent delinquency showed worse fit than the above-described non-linear LGM. This indicates that the slope of adolescent delinquency was needed to describe the growth in this construct. Hence the non-linear LGM of adolescent delinquency for the parallel process LGM’s was retained.
Parallel Process LGMs
For the parallel process LGMs, the best-fitting non-linear LGMs for impulsivity, future orientation, delinquency of friends and adolescent delinquency were retained (see Table 3 and Fig. 2). The correlations between the growth factors are reported in Table 5a and b.
Table 5
Results of the (a) multi-group parallel process LGM’s of the co-development between delinquency of friends with adolescent delinquency and impulsivity (b) alternative parallel process LGM for the co-development of school future orientation, co-offending and delinquency of friends
Delinquency of friends
(a)
Non Co-offending
Model
Co-offending
Model
Intercept
Non-linear slope
Intercept
Non-linear slope
Intercept
0.458
−0.300
0.428***
−0.364***
Non-linear slope
−0.218
0.404
−0.388**
0.652***
Impulsivity
Intercept
0.246***
−0.007
0.046
−0.016
Non-linear slope
−0.045
0.051
−0.018
0.118
(b)
Co-offending
Delinquency of friends
Intercept
Linear slope
Intercept
Non-linear slope
School Future orientation
Intercept
0.455***
0.424
0.330***
0.038
Non-Linear slope
0.345*
0.438
0.122
0.060
Correlations between the slopes are depicted with bold font and correlations between the intercepts are italicized. Controlled variables included gender, educational track, ethnicity, and SES
*p < 0.05; **p < 0.01;***p < 0.001
The “adolescent delinquency and delinquency of friends” multi-group model (Chi-square (28) = 71.208, p < 0.001) had a moderately good fit: RMSEA = 0.053; CFI = 0.959; TLI = 0.885; SRMR = 0.028. The intercept of adolescent delinquency was positively correlated with the intercept of delinquency of friends, but only in the co-offending model. Additionally, co-development existed between adolescent delinquency and delinquency of friends. Namely, the slopes of adolescent delinquency and delinquency of friends were positively correlated in both the non co-offending model and the co-offending model. These results suggest that increases in adolescent delinquency (i.e., upward/positive slopes) were associated with increases in delinquency of friends (i.e., slower declines) in both models. Moreover, a significant moderation effect was found (Wald χ2 (1) = 22.204; p < 0.001), which implies that the co-development between adolescent delinquency and delinquency of friends in the co-offending model was significantly stronger than the co-development between these variables in the non co-offending model. In more substantive terms, the results showed that engaging in co-offending exacerbated the co-development between adolescent delinquency and delinquency of friends. Hence, this co-development exists at least in part because adolescents are engaging in delinquency with their friends (co-offending).
The “impulsivity and delinquency of friends” multi-group model (Chi-square (30) = 42.059, p = 0.071) had a very good fit: RMSEA = 0.027; CFI = 0.977; TLI = 0.940; SRMR = 0.024. For the non co-offending model, the intercepts of impulsivity and delinquency of friends were significantly and positively correlated, indicating that a higher initial level of impulsivity is related to a higher initial level of delinquency of friends. However, there were no significant correlations between these intercepts in the co-offending model. Next, the slopes of impulsivity and delinquency of friends were not significantly correlated in the non co-offending model or in the co-offending model. Thus these results do not suggest co-development between these two constructs. Finally, there was no significant moderation effect of co-offending (Wald χ2 (1) = 1.539; p = 0.215). This indicates that the correlations between the slopes of impulsivity and delinquency of friends did not significantly differ across the co-offending model versus the non co-offending model.
As mentioned above, the “school future orientation and friends’ delinquency” multi-group model did not converge, hence the moderation analyses were conducted in an alternative manner—without the use of a multi-group model (see Table 5b). This alternative parallel process LGM (Chi-square (29) = 73.326, p < 0.001) showed good fit: RMSEA = 0.035; CFI = 0.960; TLI = 0.900; SRMR = 0.022. Results showed that the intercepts of future orientation and co-offending were negatively correlated, indicating that a higher initial level of future orientation is related to a lower initial level of co-offending. Likewise, the intercepts of school future orientation and delinquency of friends were negatively correlated, indicating that a higher initial level of future orientation is related to a lower initial level of delinquency of friends. As for co-development, the slopes of school future orientation were not significantly correlated with delinquency of friends and neither with co-offending, however. No co-development was detected. Furthermore, delinquency of friends and co-offending did not interact to predict school future orientation (Wald χ2 (1) = 2.112; p = 0.146). In other words the correlations between the slopes of delinquency of friends and school future orientation versus the correlations between the slopes of co-offending and school future orientation did not significantly differ from each other. No moderation effect was found.
Sensitivity Analyses
For the delinquency scale, most participants only had experience with the items that reflected minor delinquency (e.g., stealing, vandalism). The LGM models were re-run to determine whether an adjusted scale with only such minor delinquency items would alter the interpretation of the findings. This was not the case.
Discussion
Friends’ delinquency has been consistently linked to the development of adolescents’ delinquency. However, there remain conceptual and methodological gaps in the literature on such peer delinquency in general. The current study aimed to shed light on some of these issues, while drawing upon the companions in crime hypothesis, the differential association theory, and the psychosocial maturity hypothesis. In line with these theories, the current study investigated whether delinquency shows co-development with both friends’ delinquency and short-term mindsets, and whether such co-development is moderated by co-offending. In doing so, links from ethnicity, gender, SES and educational track to the initial levels and the development of the above-mentioned variables of interest were controlled for. The hypotheses were partially supported. First, linear decreases were found in co-offending throughout adolescence, whereas there were non-linear changes in short-term mindsets which reflected a peak in such behavior during mid-adolescence. On average, no significant increases or declines in delinquency was detected, however, there was significant variance for the growth factors. As for the hypothesized co-development between these constructs, the findings revealed co-development between best friends’ delinquency and adolescents’ delinquency, and this link was stronger when adolescents had experience with co-offending. Hence a moderation effect of co-offending was present. However, there was no co-development between friends’ delinquency and short-term mindsets, and neither did co-offending moderate such hypothesized co-development. These main findings are briefly discussed below.
Co-development of Friend’s Delinquency and Adolescent Delinquency
The development of friends’ delinquency was correlated with the development of adolescents’ delinquency. These findings are consistent with a plethora of studies on the association between peer delinquency and adolescent delinquency (see: Brechwald and Prinstein 2011). However, this appears to be among the first longitudinal studies to specifically investigate whether the co-development of the trajectories of friends’ delinquency and adolescents’ delinquency is stronger when adolescents co-offend (i.e., the companions in crime hypothesis). Nevertheless, these results concur with speculations that co-offending sets a more direct setting for learning of delinquent behaviors, which is further assumed to increase delinquency (Dynes et al. 2015). The only other similar study to also consider both delinquency of peers and co-offending, was a cross-sectional study based on 90% court-involved males and showed via moderation analyses that delinquency of friends is particularly associated with increased delinquency when co-offending is present (Dynes et al. 2015). The current findings extends those findings (Dynes et al. 2015) by demonstrating that this moderation effect can also be generalized to mix-gender community samples. Furthermore, the cross-sectional nature of the aforementioned study (Dynes et al. 2015) and its interaction analyses differ from the current study which examined “parallel” longitudinal co-development, which demonstrates the long-term enduring effects of these findings.
Co-development of Friends’ Delinquency and Short-term Mindsets
The present study did not demonstrate co-development between delinquency of friends and short-term mindsets, or that co-offending moderates this co-development. Nevertheless, similar to several cross-sectional studies (Burt et al. 2006; Chapple 2005; McGloin and Shermer 2009), the current study generally did find some evidence that higher initial levels of friends’ delinquency were associated with higher initial levels of indicators of short-term mindsets. However, the non-significant longitudinal findings for the co-development between best friends’ delinquency and short-term mindsets are inconsistent with what is likely the only other longitudinal study (Goldweber et al. 2011) that investigated a similar research question. Namely, unlike the present study, it was reported that increasingly solo offenders and exclusively solo-offenders exhibited more psychosocial maturity (e.g., lower levels of short-term mindsets) than persons who at least sometimes offended in groups (i.e., “mixed-style offender”; Goldweber et al. 2011; see also: Ashton et al. 2020). Perhaps the current results differ from the abovementioned results (Goldweber et al. 2011) because of dissimilarities in sample characteristics and methodology.
Of note, the only other similar longitudinal study (Goldweber et al. 2011) was based on a sample of serious male offenders whereas the current sample included community mix-gender adolescents. Perhaps only more serious forms of co-offending is associated with short-term mindsets. Secondly, as for differences in methodology, the current analyses investigated the development of friends’ delinquency in relation to short-term mindsets with co-offending as a moderator. In contrast, the prior analyses that were used (Goldweber et al. 2011) focused on co-offending in relation to short-term mindsets, without investigating mere delinquency of peers, and neither did those analyses consider a moderating role of co-offending. Thirdly, instead of using one measurement wave of short-term mindsets and group trajectory modeling, the current analyses were based on three measurement waves of both short-term-mindsets and friends’ delinquency. Finally, the current study also controlled for multiple demographic and socioeconomic factors, which was not the case in the above-mentioned study (Goldweber et al. 2011). Thus the current methodology was more stringent in some aspects, as it took more controls into account. Such stringent controls perhaps also made it more challenging to find long-term significant effects.
Taken together, the current results suggest that co-offending exacerbates the association between friends’ delinquency and adolescents’ delinquency. Thus co-offending likely provides direct access to a setting in which individuals continue to model the delinquency they learned with their friends. The following example gives a scenario in which this can be the result. “X has a friend Y, who vandalizes things, and X knows about it. Y then introduces X to a joint vandalizing setting (their former school) where X is exposed to vandalism, takes part in it, and learns the technique. As a result, X’s own delinquent activity increases thereafter independently of Y’s co-presence”. However, the present results do not suggest that friends’ delinquency is also longitudinally related to short-term mindsets via co-development, despite the some base-line level correlations between these behaviors. Furthermore, similar to some other research, the current findings do not suggest that the transmission of crime-condoning tendencies of delinquent peers is dependent on co-offending (Hochstetler et al. 2002), as co-offending was not a significant moderator.
Strengths, Limitations and Future Directions
There are also some limitations of the current study that should be mentioned. First, in (developmental) psychology, reports on delinquency of peers is the traditional method for assessing peer delinquency. However, it is important to note that adolescents might erroneously project their own delinquency onto their peers (e.g., Young et al. 2013; 2014). The “delinquency with friends” (co-offending) measure in the current study is not such a perceptual measure, as the respondents were physically present with their friends to witness the delinquency that occurred during such co-offending. Thus such a measure makes the abovementioned “projection errors” less likely or even impossible. However, the delinquency of best friends measure that was used is a perceptual measure, and it thus might be biased by the above-described “projection errors”. In any case, it is conceivable that such projection errors would be more likely among ancillary friends and less likely among best-friends relationships, which were investigated in the current study. This is because individuals in best-friend relationships are closer to each other, and therefore their perceptions of each other’s behaviors are deemed to be more reliable (for a discussion see: Rees and Pogarsky 2011). Furthermore, also of note is that what adolescents merely perceive to be true about their friends has also been shown to be decisive for predicting their behavior, independent of projection errors (Goldweber et al. 2011; Brechwald and Prinstein 2011).
Additional factors that could moderate peer influence that were not taken into account are: time spent with peers, group size of the peer networks, and peer status.
Past and more recent studies on group conformity has shown that peer influences can occur even among strangers (e.g., Asch 1951; Knoll et al. 2015). Strangers have spent no prior time together, whereas in the current study, adolescents reported on individuals they considered as their (best) friends. Hence it is reasonable to assume that the adolescent participants at least spent some time with the persons they indicated to be their (best-)friends. Additionally, a precondition for co-offending is spending time together. Thus taking prior research on peer conformity into account—since the current peer measures captured “friends” relations—it is plausible that influence processes could have occurred regardless of how much time was actually spent together between the target adolescents and their friends (for a discussion, see: Brechwald and Prinstein 2011).
As for group size, the larger the network of friends that adolescents have, the fewer time they would be able to spend with each person in their network. However, perhaps especially for deviant behavior such as delinquency, peers in broad and diffuse networks could also influence each other—independent of the size of the peer network (Brechwald and Prinstein 2011). However, of note is that larger groups have been shown to produce more violent behavior (see e.g., Lantz 2020). Although significant development links between friends’ delinquency and adolescents’ delinquency were present in the current study that did not account for group size, it would still be worthwhile for future studies—especially on co-offending—to investigate whether the size of co-offending groups further moderates peer influence effects.
A final important characteristic of the peer network that could have impacted the current results is peer status. Namely, a comprehensive review showed that peer conformity for delinquent behaviors and attitudes is stronger when the peer has a high status (Brechwald and Prinstein 2011). Also, at least one study demonstrated that older children who reported that peer-directed aggressive behavior is related to “coolness” (i.e., high peer status) showed subsequent increases in antisocial behavior during adolescence (Juvonen and Ho, 2008).
Of note, in addition to above-mentioned peer “influence” processes, just as how delinquent persons might (self-)select into delinquent peer groups (Moffitt 1993), persons with short-term mindsets might equally (self-)select into delinquent peer-groups (Chapple 2005). Furthermore, besides the abovementioned peer network characteristics, other factors such as genetics, and relatedly family relations are also important to consider in future research on peer delinquency. The robustness of the current results could further be strengthened through the use of multi-informant measures with a substantial amount of items. Namely, some of the current measures had two items which is subjected to the limitation of idiosyncratic variation (Check and Schutt 2012). Thus to overcome such limitations more items are recommended per scale (Check and Schutt 2012). Of note, although the delinquency measure that was used included many items, most adolescents only had experience with the items that reflected minor delinquency (e.g., stealing). However, the main results remained the same when the analyses were re-run with only those minor delinquency items. Finally, as for future directions, building on the significant interrelations found in the current study, future studies could further investigate mediational (e.g., via cross-lagged-panel models) and other moderating hypotheses (e.g., with peer status and/or peer group size as potential moderators).
Acknowledgements
The authors would like to express their sincere thanks to the youths, parents, and teachers for participating in the study. Moreover, the authors are grateful to all the interviewers and undergraduate students for their help in data collection and coding.
Authors’ Contributions
DR developed the study concept and design and provided critical revisions; IND developed the study concept and design, performed the data-analysis and interpretation, drafted the manuscript and provided critical revisions; JvG developed the study concept and design and provided critical revisions; and ME developed the study concept and design and provided critical revisions. All authors approved the final manuscript.
Funding
The research reported in this manuscript was financially supported by a Consolidator Grant of the European Research Council (PI: Jean-Louis van Gelder; Grant number 772911—CRIMETIME). This work was also supported by the Swiss National Science Foundation (formal PI: Michael Shanahan; Grant number: 10FI14_170409), the Jacobs Foundation, the Swiss Federal Office of Public Health, the Canton of Zurich Ministry of Education, and the Julius Baer Foundation.
Data Sharing and Declaration
The datasets generated and/or analyzed during the current study are not publicly available but are available from the corresponding author on reasonable request.
Compliance with Ethical Standards
Conflict of Interest
The authors declare no competing interests.
Ethical Approval
Given the minimally intrusive nature of the study design, questions and interventions, as well as the focus on social science research questions, the relevant Ethics Committee of the Canton of Zurich issued, based on the Swiss Human Research Act, a “declaration of no objection” for the Zurich Project on the Social Development from Childhood into Adulthood (z-proso). It states that the project falls outside the remit of the Ethics Committee of the Canton of Zurich and furthermore declared z-proso as ethically unproblematic. For the last wave (W8), ethical approval was given by the ethics committee of the Faculty of Arts and Social Sciences of the University of Zurich.
Informed consent from the participants were obtained in accordance with the relevant national regulations, and all data were processed and stored according to data protection regulations.
Publisher’s note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
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Steinberg, L., Cauffman, E., Woolard, J., Graham, S., & Banich, M. (2009). Are adolescents less mature than adults? Minors’ access to abortion, the juvenile death penalty, and the alleged apa “flip-flop”. American Psychologist, 64(7), 583–594. https://doi.org/10.1037/a0014763. CrossRef
Stolzenberg, L., & D’Alessio, S. J. (2008). Co-offending and the age-crime curve. Journal of Research in Crime and Delinquency, 45(1), 65–86. https://doi.org/10.1177/0022427807309441. CrossRef
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Van Gelder, J. L., Luciano, E. C., Weulen Kranenbarg, M., & Hershfield, H. E. (2015). Friends with my future self: a longitudinal vividness intervention reduces delinquency. Criminology, 53, 158–79. CrossRef
van Gelder, J. L., Averdijk, M., Ribeaud, D., & Eisner, M. (2020). Sanctions, short‐term mindsets, and delinquency: reverse causality in a sample of high youth. Legal and Criminological Psychology, 25, 199–218. CrossRef
Van Gelder, J. L., Averdijk, M., Ribeaud, D., & Eisner, M. (2018). Punitive parenting and delinquency: the mediating role of short-term mindsets. The British Journal of Criminology, 58(3), 644–666. CrossRef
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Metagegevens
Titel
The Co-development of Friends’ Delinquency with Adolescents’ Delinquency and Short-term Mindsets: The Moderating Role of Co-Offending
Auteurs
Ivy N. Defoe
Jean-Louis van Gelder
Denis Ribeaud
Manuel Eisner
Publicatiedatum
21-04-2021
Uitgeverij
Springer US
Gepubliceerd in
Journal of Youth and Adolescence / Uitgave 8/2021
Print ISSN: 0047-2891
Elektronisch ISSN: 1573-6601
DOI
https://doi.org/10.1007/s10964-021-01417-z
Naar de uitgave | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.7032567262649536, "perplexity": 8091.665293086803}, "config": {"markdown_headings": false, "markdown_code": false, "boilerplate_config": {"ratio_threshold": 0.3, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2022-40/segments/1664030333541.98/warc/CC-MAIN-20220924213650-20220925003650-00080.warc.gz"} |
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## appleduardo Group Title whats the integral of the following function? one year ago one year ago Edit Question Delete Cancel Submit
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1. appleduardo
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$\int\limits_{}^{}\frac{ dx }{ x ^{2} +2x + 1}$
• one year ago
2. harsh314
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take $x ^{2}+2x+1=(x+1)^{2}$ and proceed by substiution
• one year ago
3. harsh314
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did u get it..............
• one year ago
4. appleduardo
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yeah! but i forgot to type 2 before x^2, :/ so the function is:$\int\limits_{}^{}\frac{ dx }{ 2x^{2} + 2x +1 }$
• one year ago
5. appleduardo
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what i did is this: $\frac{ 1 }{ 2 }\int\limits_{}^{}\frac{ dx }{ x ^{2} +2x +1}$ but then i get stuck!
• one year ago
6. harsh314
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then divide and multiply the whole denominator by 2$2(x ^{2}+x+\frac{ 1 }{ 2 })$ then you need to make it into a square expression as$x ^{2}+x*2*\frac{ 1 }{ 2 }+\frac{ 1 }{ 4 }-\frac{ 1 }{ 4 }+\frac{ 1 }{ 2 }$add 1/4 and subtract 1/4 then $(x+\frac{ 1 }{ 2 })^{2}=x^{2}+x+\frac{ 1 }{ 4 }$substitute and then solve
• one year ago
7. appleduardo
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yeah thanks, i will try and ill post when im done :D
• one year ago
8. appleduardo
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i got: $2arc tg \frac{ x +0.5 }{ 0.5 } + c$ is that correct?
• one year ago
9. appleduardo
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(correction)$arc tg \frac{ x +0.5 }{ 0.5 } + c$
• one year ago
10. harsh314
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the question takes the form................$\frac{ 1 }{ (x+\frac{ 1 }{ 2 })^{2}-(\frac{ 1 }{ \sqrt{2} })^{2} }$
• one year ago
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Thanks for being so helpful in mathematics. If you are getting quality help, make sure you spread the word about OpenStudy. | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9995753169059753, "perplexity": 16076.807292745347}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 5, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2014-42/segments/1414119645898.42/warc/CC-MAIN-20141024030045-00197-ip-10-16-133-185.ec2.internal.warc.gz"} |
https://infoscience.epfl.ch/record/165959 | ## Josephson current in a superconductor -- ferromagnet -- superconductor junction with in-plane ferromagnetic domains
We study a diffusive superconductor--ferromagnet--superconductor (SFS) junction with in-plane ferromagnetic domains. Close to the superconducting transition temperature, we describe the proximity effect in the junction with the linearized Usadel equations. We find that properties of such a junction depend on the size of the domains relative to the magnetic coherence length. In the case of large domains, the junction exhibits transitions to the $\pi$ state, similarly to a single-domain SFS junction. In the case of small domains, the magnetization effectively averages out, and the junction is always in the zero state, similarly to a superconductor--normal metal--superconductor (SNS) junction. In both those regimes, the influence of domain walls may be approximately described as an effective spin-flip scattering. We also study the inhomogeneous distribution of the local current density in the junction. Close to the 0--$\pi$ transitions, the directions of the critical current may be opposite in the vicinity of the domain wall and in the middle of the domains.
Published in:
Phys. Rev. B 76, 134502 (2007)
Year:
2007
Laboratories: | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.854910135269165, "perplexity": 1090.19551000822}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.3, "absolute_threshold": 20, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2018-17/segments/1524125946807.67/warc/CC-MAIN-20180424154911-20180424174911-00150.warc.gz"} |
https://mathoverflow.net/questions/23478/examples-of-common-false-beliefs-in-mathematics/23505 | # Examples of common false beliefs in mathematics
The first thing to say is that this is not the same as the question about interesting mathematical mistakes. I am interested about the type of false beliefs that many intelligent people have while they are learning mathematics, but quickly abandon when their mistake is pointed out -- and also in why they have these beliefs. So in a sense I am interested in commonplace mathematical mistakes.
Let me give a couple of examples to show the kind of thing I mean. When teaching complex analysis, I often come across people who do not realize that they have four incompatible beliefs in their heads simultaneously. These are
(i) a bounded entire function is constant;
(ii) $\sin z$ is a bounded function;
(iii) $\sin z$ is defined and analytic everywhere on $\mathbb{C}$;
(iv) $\sin z$ is not a constant function.
Obviously, it is (ii) that is false. I think probably many people visualize the extension of $\sin z$ to the complex plane as a doubly periodic function, until someone points out that that is complete nonsense.
A second example is the statement that an open dense subset $U$ of $\mathbb{R}$ must be the whole of $\mathbb{R}$. The "proof" of this statement is that every point $x$ is arbitrarily close to a point $u$ in $U$, so when you put a small neighbourhood about $u$ it must contain $x$.
Since I'm asking for a good list of examples, and since it's more like a psychological question than a mathematical one, I think I'd better make it community wiki. The properties I'd most like from examples are that they are from reasonably advanced mathematics (so I'm less interested in very elementary false statements like $(x+y)^2=x^2+y^2$, even if they are widely believed) and that the reasons they are found plausible are quite varied.
• I have to say this is proving to be one of the more useful CW big-list questions on the site... – Qiaochu Yuan May 6 '10 at 0:55
• The answers below are truly informative. Big thanks for your question. I have always loved your post here in MO and wordpress. – Unknown May 22 '10 at 9:04
• wouldn't it be great to compile all the nice examples (and some of the most relevant discussion / comments) presented below into a little writeup? that would make for a highly educative and entertaining read. – Suvrit Sep 20 '10 at 12:39
• It's a thought -- I might consider it. – gowers Oct 4 '10 at 20:13
• Meta created tea.mathoverflow.net/discussion/1165/… – user9072 Oct 8 '11 at 14:27
Let $(X,\tau)$ be a topological space. The false belief is: "Every sequence $(x_n)$ in $X$ with an accumulation point $a\in X$ has a subsequence that converges to $a$". I subscribed to this intuitively until I stumbled over a counterexample, see http://dominiczypen.wordpress.com/2014/10/13/accumulation-without-converging-subsequence/
Some things from pseudo-Riemannian geometry are a bit hard to swallow for students who have had previous exposure to Riemannian geometry. Aside from the usual ones arising from sign issues (like, in a two dimensional Lorentzian manifold with positive scalar curvature, time-like geodesics will not have conjugate points), an example is that in Riemannian manifolds, connectedness + geodesic completeness implies geodesic connectedness (every two points is connected by a geodesic). This is not true for Lorentzian manifolds, and the usual example is the pseudo-sphere.
I just realized yesterday that, given $A \to C, B \to C$ in an abelian category, the kernel of $A \oplus B \to C$ is not the direct sum of the kernels of $A \to C, B \to C$.
"the quadratic variation of a Brownian motion between $0$ and $T$ is equal to $T$"
this is only true that if $\mathcal{D}^N$ is a nested sequence of partitions of $[0,T]$ (with mesh size going to $0$) then the quadratic variation of a Brownian motion along these partitions converges towards $T$, almost surely. If we define the quadratic variation of a continuous function $f$ as we would like to, $$Q(f,[0,T]) = \sup_{0=t_0<\ldots, t_n=T } \sum |f(t_k)-f(t_{k+1})|^2,$$ then the Brownian paths have almost surely infinite quadratic variation.
This was something I had never noticed until I read the wonderful book "Brownian motion" by Peter Morters and Yuval Peres.
• The key here is that quadratic variation is defined as a limit in probability, not a limit almost surely. – nullUser Jul 8 '13 at 15:46
Before reading about it, I really thought that if $f \colon [0,1] \times [0,1] \to [0,1]$ is a function with the following properties:
1. for any $x \in [0,1]$ the function $f_x\colon [0,1] \to [0,1]$ defined by $f_x(y)=f(x,y)$ is Lebesgue measurable, and also the function $f^y \colon [0,1]\to[0,1]$ defined by $f^y(x)=f(x,y)$ is Lebesgue measurable, for all $y \in [0,1]$;
2. both $\varphi(x)=\int_0^1 f_x d\mu$ and $\psi(y)=\int_0^1 f_y d\mu$ are Lebesgue measurable.
Then the two iterated integrals $$\int_0^1\varphi(x)dx \mbox{ and } \int_0^1\psi(y)dy$$ should be equal. This is false (see Rudin's "Real and Complex Analysis", pag. 167), at least if you assume the continuum hypothesis.
• I really like this example from Rudin's book. Do you know if there exist such an example that does not use the continuum hypothesis (or if it's even possible to find one)? – Malik Younsi Jul 28 '10 at 13:39
• I don't know, but this could be a good questions for MO! – Ricky Jul 28 '10 at 14:28
• For others reading, the hypothesis left off here is that one must assume $f$ is measurable with respect to the product $\mathcal{B}[0,1] \times \mathcal{B}[0,1]$. – nullUser Jul 8 '13 at 15:39
Complex variables: "An entire function that is onto and locally one-to-one is globally one-to-one."
Counterexample: $f(z) := \int_0^z \exp(\zeta^2)\,d\zeta$
I'll leave the proof that this is indeed a counterexample as a pleasant exercise.
(I believe this example is due to Lawrence Zalcman.)
• Let's see if you TeX code can be improved: $$f(z) := \int_0^z \exp(\zeta^2)\,d\zeta$$ (The backslash in \exp not only should prevent italicization but should also result in proper spacing in things like "a \exp b", and the space before d\zeta seems appropriate.) – Michael Hardy Jul 8 '10 at 15:19
• @MichaelHardy, if we're going to {\TeX}pick, then surely it should be something like ${\mathrm d}\zeta$ (rather than $d\zeta$), since the $\mathrm d$ is an operator (rather than a variable)? – LSpice Dec 12 '13 at 23:20
• @LSpice : I understand the case for that usage; in particular, it allow the use of $d$ as a variable, so that one can write $\dfrac{\mathrm{d}f}{\mathrm{d}d}$, etc. However, the usage with the $d$ italicized as if it were a variable is standard although not universal. – Michael Hardy Dec 13 '13 at 0:58
Inversion is an automorphism of a group. ('Cause it, like, preserves the conjugacy classes and all that...)
I don't know how common this is, but I've noticed it half an hour ago in some notes I had written: If $J$ is a finitely generated right ideal of a not necessarily commutative ring $R$, and $n$ is natural, then $J^n$ is finitely generated, isn't it?
No, it isn't. For an example, try $R=\mathbb Z\left\langle X_1,X_2,X_3,...\right\rangle$ (ring of noncommutative polynomials) and $J=X_1R$.
• Omg, I will have to be careful about that. Thanks Darij ;). – Martin Brandenburg Apr 12 '11 at 8:45
(*) "Let $(I,\leq)$ be a directed ordered set, and $E=(f_{ij}:E_i\to E_j)_{i\geq j}$ be an inverse system of nonempty sets with surjective transition maps. Then the inverse limit $\varprojlim_I\,E$ is nonempty."
This is true if $I=\mathbb{N}$ ("dependent choices"), and hence more generally if $I$ has a countable cofinal subset. But surprisingly (to me), those are the only sets $I$ for which (*) holds for every system $E$. (This is proved somewhere in Bourbaki's exercises, for instance).
Of course, other useful cases where (*) holds are when the $E_i$'s are finite, or more generally compact spaces with continuous transition maps.
"The universal cover of $SL_2(R)$ is a universal central extension" (which I believed until recently...)
False statement: If $A$ and $B$ are subsets of $\mathbb{R}^d$, then their Hausdorff dimension $\dim_H$ satisfies
$$\dim_H(A \times B) = \dim_H(A) + \dim_H(B).$$
EDIT: To answer Benoit's question, I do not know about a simple counterexample for $d = 1$, but here is the usual one (taken from Falconer's "The Geometry of Fractal Sets"):
Let $(m_i)$ be a sequence of rapidly increasing integers (say $m_{i+1} > m_i^i$). Let $A \subset [0,1]$ denote the numbers with a zero in the $r^{th}$ decimal place if $m_j + 1 \leq r \leq m_{j+1}$ and $j$ is odd. Let $B \subset [0,1]$ denote the numbers with a zero in the $r^{th}$ decimal place if $m_{j} + 1 \leq r \leq m_{j+1}$ and $j$ is even. Then $\dim_H(A) = \dim_B(A) = 0$. To see this, you can cover $A$, for example, by $10^k$ covers of length $10^{- m_{2j}}$, where $k = (m_1 - m_0) + (m_3 - m_2) + \dots + (m_{2j - 1} - m_{2j - 2})$.
Furthermore, if $\mathcal{H}^1$ denotes the Hausdorff $1$-dimensional (metric) outer measure of $E$, then the result follows by showing $\mathcal{H}^1(A \times B) > 0$. This is accomplished by considering $u \in [0,1]$ and writing $u = x + y$, where $x \in A$ and $y \in B$. Let $proj$ denote orthogonal projection from the plane to $L$, the line $y = x$. Then $proj(x,y)$ is the point of $L$ with distance $2^{-1/2}(x+y)$ from the origin. Thus, $proj( A \times B)$ is a subinterval of $L$ of length $2^{-1/2}$. Finally, it follows:
$$\mathcal{H}^1(A \times B) \geq \mathcal{H}^1(proj(A \times B)) = 2^{-1/2} > 0.$$
• Well, it's disappointing that this fails, although it hadn't occurred to me to conjecture it. – Toby Bartels Apr 4 '11 at 9:53
• Actually, the situation is worse than I say: there exist sets $A, B \subset \mathbb{R}$ with $dim_H(A \times B )= 1$, and yet $\dim_h(A) = \dim_H(B) = 0$. – JavaMan Apr 5 '11 at 6:22
• By the way, is there a simple counter-example with $A=B$? – Benoît Kloeckner May 9 '11 at 7:51
• Nice, I did not know that, though Hausdorff dimension is part of my mathematical life! But the sets I study (Julia sets in complex dimension one) usually are uniform enough that this does not occurr, I guess. Here's what happens, morally, in the example given here: the scales epsilon at which you have good covers of A and the scales at which you have good covers of B are disjoint. The products of these good covers are extremely distorted : they are thin rectangles, instead of squares. – Arnaud Chéritat Oct 18 '15 at 13:25
False belief: A function being continuous in some open interval implies that it is also differentiable on some point in that interval:
Counterexample:
The Weierstrass function is an example of a function that is continuous everywhere but differentiable nowhere:
$f(x) = \sum_{n=0}^\infty a^n \cos(b^n \pi x)$
Where $a \in (0, 1)$, $b$ is a positive odd integer, and $ab > 1 + \frac{3\pi}{2}$. The function has fractal-like behavior, which leads to it not being differentiable. This notion is rather disheartening to most calculus students, though.
• Related: if f is continuous on the interval I, there must be an interval J in I on which f is monotone. Easily believed by the beginner. – Thierry Zell Aug 31 '10 at 2:34
• Did you mean "differentiable on some point in that interval:" ? – Rasmus Sep 18 '13 at 19:13
• Haha, figures that I edit a 3 year old post to introduce an even worse typo. Yes, that is what I meant. – Jon Paprocki Sep 18 '13 at 22:53
I guess you don't want commonly held beliefs of students that for every real number there is a next real number, or that convergent sequences are eventually constant. A version I saw in a book asked whether points on a line "touch." Understanding the topology of a line is a challenge for many students, although presumably not for most mathematicians.
Here is a more esoteric belief that I have even seen in some books:
"The Banach-Tarski Paradox says that a ball the size of a pea can be cut into 5 pieces and reassembled to make a ball the size of the sun."
As a consequence of the Banach-Tarski paradox, a ball the size of a pea can be partitioned (not really "cut") into a finite number of pieces which can be reassembled into a ball the size of the sun, but a simple outer measure argument implies that the number of pieces must be very large (I roughly estimate at least $10^{30}$). The number 5 probably comes from the fact that the basic Banach-Tarski paradox is that a ball of radius 1 can be partitioned into 5 pieces which can be reassembled into two disjoint balls of radius 1. (It can almost, but not quite, be done with four pieces; one of the five pieces can be taken to be a single point.)
Teaching introduction to analysis, I had students using the "fact" that if $f: [a,b] \rightarrow \mathbb{R}$ is continuous, then $[a,b]$ can be divided to subintervals $[a,c_1],[c_1,c_2],...,[c_n,b]$ such that $f$ is monotone on every subinterval. For instance you can use this "fact" to "prove" the (true) fact that $f$ must be bounded on $[a,b]$. Also, some students used the same "fact", but with countably many subintervals. I found this mistake hard to explain to students, because constructing a counterexample (such as the Weierstrass function) is impossible at the knowledge level of an introduction course.
• Why not $x \sin(1/x)$ as example? – user9072 Jan 2 '14 at 17:33
• It is in the case of finitely many subintervals, but not in the case of countably many subintervals. – Izhar Oppenheim Jan 2 '14 at 19:17
• You can surely discuss fractal shapes without needing to go into the details of a technical counterexample. The point seems to be that it is hard to imagine that "increasing at a point" and "increasing in a neighborhood of a point" are not the same for continuous functions. You can give easy examples showing that indeed they disagree, locally, and fractals suggest that you can make the disagreement happen everywhere. You can revisit this later, once more technology has been set in place. – Andrés E. Caicedo Jan 2 '14 at 23:44
• While technically it is true one can do it with countably many for the function I gave (if one includes degenerate intervals) I would be surprised if not at least some (or rather most) of the confusion of the students could be addressed by the example (possibly continuing with discussion along the lines suggested by @AndresCaicedo). – user9072 Jan 5 '14 at 16:50
False belief: Any orthonormal basis of a subvectorspace $W\subset V$ of an inner product space $V$ can always be extended to an ONB of $V$.
Counterexample: Let $V$ be $\bigoplus_{i\ge 1} \mathbb{R}$ with the inner product given by $\langle a_*,b_*\rangle =\sum_{i\ge 1} a_ib_i$ and let $W$ be the subvectorspace of $V$ spanned by $e_1+e_i$ for $i\ge 2$. The given set is basis and we can apply Gram-Schmidt to obtain an ONB.
However $W^\perp = 0$ so there is no way to complete it. Related false belief: $(W^\perp)^\perp=W$. These beliefs are all true in finite dimensions, but false in general.
• That's why we like Hilbert spaces (inner product spaces that are complete w.r.t. the inner-product norm) much better than arbitrary inner-product spaces. – Noam D. Elkies Mar 4 '16 at 4:08
If $H$ and $K$ are subgroups of $G$, then $HK$ is a subgroup of $G$.
• Hm, wonder how common that false belief actually is. It seems obviously implausible in the nonabelian case. – Todd Trimble Sep 6 '15 at 15:39
• Its common, specially when undergraduates use product formula : $|HK|=\frac{|H||K|}{| H \cap K | }$ Because all of them are subgroup, except $HK$ probably. – user68208 Apr 10 '16 at 17:30
The following seems not to be here yet.
Misconception.
$R[[x_1,x_2,x_3,\dotsc]]/(x_2,x_3,\dotsc)$ isomorphic to $R[[x_1]]$ ${}\hspace{118pt}$ (f)
Source of the misconception. A fallacy of type false generalization: for any $n\in\mathbb{N}$ it is true that
$R[[x_1,x_2,x_3,\dotsc,x_n]]/(x_2,x_3,\dotsc,x_n)\cong R[[x_1]]$ ${}\hspace{125pt}$ (t)
but to conclude from this that (f) was true by passing to the limit $n\to\infty$ is fallacious.
Reason for why the misconception is false. E.g. the formal power series $f:=x_2+x_3+\dotsm$ is an element of $R[[x_1,x_2,x_3,...]]$, but by the standard definition of $I:=(x_2,x_3,\dotsc)$, which after all means nothing more than the $R[[x_1,x_2,x_3,\dotsc]]$-module generated by the infinite set $\{x_i\colon i\in \omega,\ i\geq 2\}$, the ideal $I$ does not contain $f$. (Having coefficients from the huge power series ring $R[[x_1,x_2,x_3,\dotsc]]$ does not help.)
Reason for including the example. I saw this misconception in a dissertation. For obvious reasons, I won't give the source.
Further remarks. In the above, $R$ can be any commutative unital ring, and $R[[x_1,x_2,x_3,\dotsc]]$ as usual means the projective limit in the category of commutative unital rings of the diagram $\dotsm\twoheadrightarrow R[[x_1,x_2,x_3]]\twoheadrightarrow R[[x_1,x_2]]\twoheadrightarrow R[[x_1]]$ consisting of the canonical projections.
• Maybe this is just a misunderstanding of / disagreement over the "correct" definition of the symbol $R[[x_1,x_2,\ldots]]$. If one believes that it denotes the completion of the localisation of $R[x_1,x_2,\ldots]$ at its maximal ideal $(x_1,x_2,\ldots)$, then this misconception becomes a true statement. Or phrased differently: Maybe this misconception is a failure of recognising that $colim_n lim_k R[x_1,\ldots,x_n]/\mathfrak{m}_n^k \not\cong \lim_k colim_n R[x_1,\ldots,x_n]/\mathfrak{m}_n^k$. – Johannes Hahn Mar 16 '18 at 23:07
An incredibly common false belief is:
For a (say smooth, projective) algebraic variety $X$ the $K_X$-negative part of the cone $NE(X)$ is locally polyhedral.
A right statement of the theorem of the cone is
$\overline{NE(X)} = \overline{NE(X)}_{K_X \geq 0} + \sum_{i} \mathbb{R}[C_i]$ for a denumerable set $\{ C_i \}$ of rational curves, which accumulate at most on the hyperplane $K_X = 0$.
At a first glance this seems to imply that $\overline{NE(X)}_{K_X < 0}$ is locally poyhedral, but this is not true. It depends on the shape of the intersection $\overline{NE(X)} \cap \{ K_X = 0 \}$.
For instance if this latter intersection is round, and there is only one curve $C_i$, the half-cone $\overline{NE(X)}_{K_X < 0}$ is actually a circular cone! Definitely not polyhedral in any sense. I believe this behaviour can happen even with varieties birational to abelian varieties.
The strange thing about this false belief is that it is held true by many competent mathematicians (and indeed I don't believe that many undergraduates meet the theorem of the cone!).
• You meant: I believe this behaviour can happen even with (varieties birationally isomorphic to) abelian varieties. Nice example although perhaps too technical for MO. – VA. May 5 '10 at 3:27
• Incredibly common? The number of people who can even understand the statement, let alone believe it, isn't all that large... – Victor Protsak May 5 '10 at 6:57
• Yes, but among those, almost all believe that the wrong version is true. – Andrea Ferretti May 5 '10 at 10:13
• And about 50% of the large community who cannot understand the point will believe that the right version is true! Rather high percentage... – Wadim Zudilin May 5 '10 at 11:41
• I'm not sure to what extent this is a "false belief", and to what extent people are just being sloppy with the terminology "locally polyhedral". But I agree, it's disturbing to hear experts happily making this false statement, without any further comment. <i>Mea culpa:</i> An old version of the wikipedia article entitled "Cone of curves" contained this false statement. If one looks through the article history, it's not hard to see who is to blame... – user5117 May 6 '10 at 7:24
As a student, I thought (for quite a while) that our textbook had stated that tensoring commutes with taking homology groups. It wasn't until calculating the homology groups of the real projective plane over rings Z and Z/2Z that I realized my mistake.
Two very common errors I see in (bad) statistics textbooks are
(i) zero 3rd moment implies symmetry (though generally stated in terms of "skewness", where skewness has just been defined as a scaled third moment)
(ii) the median lies between the mean and the mode
(I have seen a bunch of related errors as well.)
Another one I often see is some form of claim that the t-statistic goes to the t-distribution (with the usual degrees of freedom) in large samples from non-normal distributions.
Even if we take as given that the samples are drawn under conditions where the central limit theorem holds, this is not the case. I have even seen (flawed) informal arguments given for it.
What does happen is (given some form of the CLT applies) Slutzky's theorem implies that the t-statistic goes to a standard normal as the sample size goes to infinity, and of course the t-distribution also goes to the same thing in the limit - but so, for example, would a t-distribution with only half the degrees of freedom - and countless other things would as well.
The first two errors are readily demonstrated to be false by simple counterexample, and to convince people that they don't have the third usually only requires pointing out that the numerator and denominator of the t-statistic won't be independent if the distribution is non-normal, or any of several other issues, and they usually realize quite quickly that you can't just hand-wave this folk-theorem into existence.
• In the statistics text at the college where I teach, (ii) is universal among the examples given, so I formulated the conjecture; but when I tried to prove it and thought about what the mode really is, I realised how badly behaved that can be and found immediate counterexamples. (Then this gets me wondering why anybody would bother using the mode as a statistic for anything, since it's pretty much meaningless, but never mind.) – Toby Bartels Apr 4 '11 at 9:24
• Toby: sure, you use the mode for cases when the domain of the measurement is not an ordered set but just a set without structure and so the median wouldn't make sense. – Zsbán Ambrus Apr 7 '11 at 12:01
The fundamental group of the Klein bottle is $D_\infty$, the infinite dihedral group (which is $\mathbb Z \rtimes \mathbb Z_2$).
I believed this for some time, and I seem to recall some others having the same confusion.
The group that has been mistaken for $D_\infty$ is in fact $\mathbb Z \rtimes\mathbb Z$, which can also be written with the presentation $x^2y^2=1$. The former abelianizes to $\mathbb Z_2\oplus \mathbb Z_2$, the latter to $\mathbb Z\oplus \mathbb Z_2$.
A 2-dimensional Lie group is a product of circles and lines, in particular it is abelian.
I don't know if anyone else suffered this one. The mistake is (a) in forgetting that the classification of surfaces doesn't apply since homeomorphic Lie groups are not necessarily isomorphic (e.g., the (bijective, orientation preserving) affine transformations $x\mapsto ax+b$, where $a>0, b\in \mathbb R$ are homeomorphic to $\mathbb R^2$, though not isomorphic) and (b) that Lie groups aren't necessarily connected, in particular $\mathbb R^2$ cross any finite non-abelian group is non-abelian.
• Count me in for the 2nd fallacy. – Michael Dec 3 '13 at 0:41
If $E$ is a contractible space on which the (Edit: topological) group $G$ acts freely, then $E/G$ is a classifying space for $G$.
A better, but still false, version:
If $E$ is a free, contractible $G$-space and the quotient map $E\to E/G$ admits local slices, then $E/G$ is a classifying space for $G$.
(Here "admits local slices" means that there's a covering of $E/G$ by open sets $U_i$ such that there exist continuous sections $U_i \to E$ of the quotient map.)
The simplest counterexample is: let $G^i$ denote $G$ with the indiscrete topology (Edit: and assume $G$ itself is not indiscrete). Then G acts on $G^i$ by translation and $G^i$ is contractible (for the same reason: any map into an indiscrete space is continuous). Since $G^i/G$ is a point, there's a (global) section, but it cannot be a classifying space for $G$ (unless $G=\{1\}$). The way to correct things is to require that the translation map $E\times_{E/G} E \to G$, sending a pair $(e_1, e_2)$ to the unique $g\in G$ satisfying $ge_1 = e_2$, is actually continuous.
Of course the heart of the matter here is the corresponding false belief(s) regarding when the quotient map by a group action is a principal bundle.
• I'm a little confused. How does requiring that $(e_1, e_2) \mapsto g$ be continuous fix things? In the indiscrete case, this map is continuous (since every map to the group is). And why isn't $G^i \to G^i/G$ a principal $G^i$--bundle? – Autumn Kent Mar 6 '11 at 17:52
• The group in this example starts out with some topology. (I guess I didn't specify that I was thinking of a topological group.) If G started with the indiscrete topology, then your commment makes sense, and we would have a principal bundle for this indiscrete group. But if G is not indiscrete, then the map $(e_1, e_2) \mapsto g$ is not continuous as a map into the topological group G. The proof that continuity of the translation map forces this to be a principal bundle can be found in Husemoller's book on fiber bundles (it's not hard). Let me know if this didn't answer your questions. – Dan Ramras Mar 6 '11 at 19:57
• Oh! You're saying that a point is not a classifying space for G with some other topology. I thought you were saying that $G^i/G$ wasn't $BG^i$. Thanks for the clarification! – Autumn Kent Mar 6 '11 at 20:01
• Yes, precisely. It's an odd little example, but helpful when people forget to include the proper conditions... – Dan Ramras Mar 6 '11 at 21:06
• Maybe even more amazing wrong belief in this field: $\dim(E/G)\le\dim E$ (there are counterexamples by A.N. Kolmogorov) – mikhail skopenkov Jun 9 '11 at 14:52
Duality reverses inclusions of vector spaces.
• That's funny, because I don't imagine this kind of idea would occur to someone who has just learned the definition of a dual space. That would be a strangely sophisticated mistake to make. – Thierry Zell Apr 7 '11 at 0:21
• And, once you learn that this is wrong, you can make the opposite mistake. See my comments here sbseminar.wordpress.com/2011/02/22/sobolev-spaces-on-manifolds on how surprised I was that duality DOES reverse the inclusions between Soboloev spaces. – David E Speyer Apr 11 '11 at 12:07
• The mistake is somehow in the wording. The dual of the inclusion morphism is reversed, it's just not an inclusion anymore. – Manuel Bärenz Sep 4 '15 at 15:42
A degree $k$ map $S^n\to S^n$ induces multiplication by $k$ on all the homotopy groups $\pi_m(S^n)$.
(Not sure if this is a common error, but I believed it implicitly for a while and it confused me about some things. If you unravel what degree $k$ means and what multiplication by $k$ in $\pi_m$ means, there's no reason at all to expect this to be true, and indeed it is false in general. It is true in the stable range, since $S^n$ looks like $\Omega S^{n+1}$ in the stable range, "degree k" can be defined in terms of the H-space structure on $\Omega S^{n+1}$, and an Eckmann-Hilton argument applies.)
• If $n$ is even and $x \in \pi_{2n-1}(S^n)$ and $f$ a degree $k$ map and $H$ the Hopf invariant, then $H(f_* (x)) = k^2 H(x)$. A related misbelief: if $M$ is a framed manifold and $N\to$M a finite cover, of degree $d$. Then the framed bordism classes satisfy $[N]=d [M]$. Completely wrong. – Johannes Ebert Apr 14 '11 at 9:04
Here are mistakes I find surprisingly sharp people make about the weak$^{*}$ topology on the dual of $X,$ where $X$ is a Banach space.
-It is metrizable if $X$ is separable.
-It is locally compact by Banach-Alaoglu.
-The statement $X$ is weak$^{*}$ dense in the double dual of $X$ proves that the unit ball of $X$ is weak$^{*}$ dense in the unit ball of the double dual of $X.$
The first two are in fact never true if $X$ is infinite dimensional. While both statements in the third claim are true, the second one is significantly stronger, but a lot of people believe you can get it from the first by just "rescaling the elements" to have norm $\leq 1.$ (Although the proof of the statements in the third claim is not hard). The difficulty is that if $X$ is infinite dimensional then for any $\phi$ in the dual of $X,$ there exists a net $\phi_{i}$ in the dual of $X$ with $\|\phi_{i}\|\to \infty$ and $\phi_{i}\to \phi$ weak$^{*},$ so this rescaling trick cannot be uniformly applied. Really these all boil down to the following false belief:
-The dual of $X$ has a non-empty norm bounded weak$^{*}$ open set.
Again when $X$ is infinite dimensional this always fails.
• Minor nitpick: Consider a locally compact Hausdorff space $T$. The $*$ topology on the dual of the $C^*$ algebra $C_0(T)$ is metrizable, if and only if $X$ is second countable. That is a theorem in Choquet's book on functional analysis. So your claim, that the first statement is never true in infinite dimensional situations, is false. Take e.g. $T$ being a circle. – Marc Palm Oct 6 '11 at 13:38
• I think $M(T)$ is not metrizable in the weak$^\ast$ topology, and in fact my claim that this fails for every infinite dimensional Banach space i also think is true. The rough outline of the proof I saw was this: 1. If $X^\ast$ is weak$^\ast$ metrizable, then a first countabliity at the origin argument implies that $X^\ast$ has a translation invariant metric given the weak$^\ast$ topology. 2. One can characterize completeness topologically for translation-invariant metrics, and see directly that if $X^\ast$ had a translation-invariant metric given the weak$^\ast$ topology it would be complete. – Benjamin Hayes Oct 12 '11 at 3:42
• $X^{∗}$ in the weak∗ topology is a countable union of $\{\phi\in X^{*}:\|\phi\|\leq N\}$, which have empty weak∗ interior. Hence, if the weak∗ topology were metrizable, we get a contradiction to the Baire Category Theorem. Are you sure you don't mean the weak∗ topology on the state space of $C_{0}(X)? – Benjamin Hayes Oct 12 '11 at 3:47 • Okay, excuse my false claim, I was overlooking that this holds for the subset$M^+(T)$of positive Radon measure, and does not generalize to the complex linear span. – Marc Palm Oct 16 '11 at 10:24 A random$k$-coloring of the vertices of a graph$G$is more likely to be proper than a random$(k-1)$-coloring of the same graph. (A vertex coloring is proper if no two adjacent vertices are colored identically. In this case, random means uniform among all colorings, or equivalently, that each vertex is i.i.d. colored uniformly from the space of colors.) • ...wait, what's the truth then? – Harry Altman May 10 '11 at 0:06 • It sounds plausible. – Michael Hardy May 10 '11 at 0:34 • For some graphs$G$and integers$k$, the opposite. The easiest example is the complete bipartite graph$K_{n,n}$with$k=3$. The probability a$2$-coloring is proper is about$(1/4)^n$while the same for a$3$-coloring is about$(2/9)^n$, where I've ignored minor terms like constants. The actual probabilities cross at$n=10$, so as an explicit example, a random$2$-coloring of$K_{10,10}$is more likely to be proper than a random$3$-coloring. – aorq May 10 '11 at 0:37 • This seems like a good example of a counterintuitive statement, but to call it a common false belief would mean that there are lots of people who think it's true. The question would probably never have occurred to me it I hadn't seen it here. The false belief that Euclid's proof of the infinitude of primes, on the other hand, actually gets asserted in print by mathematicians---in some cases good ones. – Michael Hardy May 10 '11 at 15:36 Let$B(r_1) \subset B(r_2)$be two open balls of radius$r_1$and$r_2$respectively. Then$r_1 \leq r_2$. Bounded metric spaces give trivial counterexamples. Also,$B \left( \frac{1}{6}, \frac{2}{3} \right) \subsetneq B \left( \frac{1}{2}, \frac{1}{2} \right)$in$(0,+ \infty)$. • What is$B(a,b)$here? – Brout Dec 3 '13 at 10:09 • Here,$B(a,b)$is the open ball of radius$b$centered at$a$. – Seirios Dec 3 '13 at 21:41 "A real symmetric matrix is positive-definite iff all the leading principal minors are positive, and positive-semidefinite iff all the leading principal minors are nonnegative." This paper collects some evidence that this belief is "common", and presents a counterexample (of size$3\times 3$. Exercise: find an example of size$2\times 2$). (Related to, but not the same as this answer.) • $$\pmatrix{0&0\cr0&-1\cr}$$ – Gerry Myerson Jul 29 '15 at 3:22 Consider the following well-known result: Let$(E,\leq)$be an ordered set. Then the following are equivalent: (i) Every nonempty subset of$E$has a maximal element. (ii) Every increasing sequence in$E$is stationary. It is immediate that (i) implies (ii). To prove the converse, one assumes that (i) is false and then "constructs step by step" a strictly increasing sequence. The common mistake (which I have seen in textbooks) is to describe the latter construction as a proof by induction. In fact, the construction uses the axiom of choice (or at least the dependent choice axiom). (As a special case, I don't think ZF can prove that every PID is a UFD.) • It’s not exactly wrong to call it a proof by induction. In ZFC, the proof of dependent choice — or of just about any instance of it, eg the one here — works by combining induction and choice. So I’d agree it’s wrong to sweep the choice under the carpet; but if you’re not explicitly invoking DC, then you will be using induction as well. – Peter LeFanu Lumsdaine Dec 1 '10 at 15:34 • Peter, let's state DC as follows: "If$(p_n:X_{n+1}\to X_n)$is an$\mathbb{N}$-projective system of nonempty sets with all$p_n$surjective , then projlim($X_n$) is nonempty." Proof from AC: put$X:=\coprod_{n\geq0}X_n$and$X^+=\coprod_{n>0}X_n$with obvious map$p:X^+\to X$. Then$p$is onto, so has a section$s$(family of sections of all$p_n$'s). Given$x_0\in X_0$, sequence$(s^n(x_0))$is an element of projlim($X_n$). I agree that we do need induction to define$s^n$. But iteration of a map is such a basic tool that I don't agree to call any proof using it a "proof by induction". – Laurent Moret-Bailly Dec 7 '10 at 11:49 Draw the graph of a continuous function$f$(from$\mathbb{R}$to$\mathbb{R}$). Now draw two dashed curves: one which everywhere a distance$\epsilon$above the graph of$f$and one which is everywhere a distance$\epsilon$below the graph of$f$. Then the open$\epsilon$-ball around$f$(with respect to the uniform norm) is all functions which fit strictly between the two dashed curves. • Surely this is true if you are talking about the closed ball, and only just barely false for the open ball (and if we were talking about functions from$[a,b]$to$\mathbb{R}$it would be true)? Or else I am one of those with the false belief... – Nate Eldredge Oct 10 '10 at 18:26 • You are right, I should have specified open ball, thanks. I think it is just barely false for the open ball. Honestly, I held this false belief until a couple of days ago, and I haven't thought much about correcting my belief. Probably the real open epsilon ball is the union of all functions that fit between dashed curves a distance strictly less than epsilon away from f? At any rate, I think the above picture is the right way to think about it most of the time. But it gives results such as$tan^{-1}\$ being in the open ball of radious pi/2 centered at 0 if you interpret it literally. – user4977 Oct 10 '10 at 19:24
• Hmm, very nice (once clarified to the open ball)! Easily dispelled as soon as you question it, but I could easily imagine using it without thinking and missing the alternation of quantifiers that’s going on under the surface. – Peter LeFanu Lumsdaine Dec 1 '10 at 15:30
## protected by François G. Dorais♦Oct 15 '13 at 2:34
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# 7.3: Heat
Learning Objectives
• To relate heat transfer to temperature change.
• Memorize temperature equations for Celsius, Fahrenheit and Kelvin conversions.
• Understand how body temperature can vary.
The concept of temperature may seem familiar to you, but many people confuse temperature with heat. Temperature is a measure of how hot or cold an object is relative to another object (its thermal energy content), whereas heat is the flow of thermal energy between objects with different temperatures. When we touch a hot object, energy flows from the hot object into our fingers, and we perceive that incoming energy as the object being “hot.” Conversely, when we hold an ice cube in our palms, energy flows from our hand into the ice cube, and we perceive that loss of energy as “cold.” In both cases, the temperature of the object is different from the temperature of our hand, so we can conclude that differences in temperatures are the ultimate cause of heat transfer.
## Temperature Scales
Temperature is a measure of the average amount of energy of motion, or kinetic energy, a system contains. Temperatures are expressed using scales that use units called degrees. There are three scales used for reporting temperatures. Figure $$\PageIndex{1}$$ compares the three temperature scales: Fahrenheit (expressed as °F), Celsius (°C), and Kelvin (K). Thermometers measure temperature by using materials that expand or contract when heated or cooled. Mercury or alcohol thermometers, for example, have a reservoir of liquid that expands when heated and contracts when cooled, so the liquid column lengthens or shortens as the temperature of the liquid changes.
Figure $$\PageIndex{1}$$: Fahrenheit, Celsius, and Kelvin Temperatures. A comparison of the three temperature scales. These thermometers have a red-colored liquid which contains alcohol and food coloring. Silver looking thermometers contain mercury, which is a neurotoxin.
In the United States, the commonly used temperature scale is the Fahrenheit scale (symbolized by °F and spoken as “degrees Fahrenheit”). On this scale, the freezing point of liquid water (the temperature at which liquid water turns to solid ice) is 32 °F, and the boiling point of water (the temperature at which liquid water turns to steam) is 212 °F.
Science also uses other scales to express temperature. For example, the Celsius scale (symbolized by °C and spoken as “degrees Celsius”) defines 0°C as the freezing point of water and 100 °C as the boiling point of water. This scale is divided into 100 divisions between these two landmarks and extended higher and lower as well. By comparing the Fahrenheit and Celsius scales, a conversion between the two scales can be determined:
$^{\circ}C= \left(^{\circ}F-32\right )\times \dfrac{5}{9} \label{F2C}$
$^{\circ}F= \left(^{\circ}C\times \dfrac{9}{5}\right)+32 \label{C2F}$
Note that science uses the Celsius and Kelvin scales almost exclusively; virtually no practicing chemist expresses laboratory-measured temperatures with the Fahrenheit scale. (In fact, the United States is one of the few countries in the world that still uses the Fahrenheit scale on a daily basis. People driving near the borders of Canada or Mexico may pick up local radio stations on the other side of the border that express the daily weather in degrees Celsius, so do not get confused by their weather reports.)
Example $$\PageIndex{1}$$: Conversions
1. What is 98.6°F in degrees Celsius?
2. What is 25.0°C in degrees Fahrenheit?
Solution
1. Using Equation \ref{F2C}, we have
\begin{align*} ^{\circ}C &= (98.6-32)\times \dfrac{5}{9} \\[5pt] &=66.6\times \dfrac{5}{9} \\[5pt] &= 37.0^{\circ}C \end{align*}
1. Using Equation \ref{C2F}, we have
\begin{align*} ^{\circ}F &= (25.0\times \dfrac{9}{5})+32 \\[5pt] &= 45.0+32 \\[5pt] &=77.0^{\circ}F \end{align*}
For more examples of how to perform these types of problems, click on this video to see your professor in action.
Exercise $$\PageIndex{1}$$
1. Convert 0°F to degrees Celsius.
2. Convert 212°C to degrees Fahrenheit.
Answer a
−17.8°C
Answer b
414°F
The fundamental unit of temperature in SI is the Kelvin (K). The Kelvin temperature scale (note that the name of the scale capitalizes the word Kelvin, but the unit itself is lowercase) uses degrees that are the same size as the Celsius degree, but the numerical scale is shifted up by 273.15 units. That is, the conversion between the Kelvin and Celsius scales is as follows:
$K=^{\circ}C+273.15 \label{C2K}$
For most purposes, it is acceptable to use 273 instead of 273.15 in Equation \ref{C2K}.
Note that the Kelvin scale does not use the word degrees; a temperature of 295 K is spoken of as “two hundred ninety-five kelvin” and not “two hundred ninety-five degrees Kelvin.”
The reason that the Kelvin scale is defined this way is that there exists a minimum possible temperature called absolute zero (zero Kelvin). The Kelvin temperature scale is set so that 0 K is absolute zero, and the temperature is counted upward from there. Normal room temperature is about 295 K, as seen in the following example.
Example $$\PageIndex{2}$$: Room Temperature
If the normal room temperature is 72.0°F, what is room temperature in degrees Celsius and kelvin?
Solution
First, we use Equation \ref{F2C} to determine the temperature in degrees Celsius:
\begin{align*} ^{\circ}C &= (72.0-32)\times \dfrac{5}{9} \\[5pt] &= 40.0\times \dfrac{5}{9} \\[5pt] &= 22.2^{\circ}C \end{align*}
Then we use Equation \ref{C2K} to determine the temperature in the Kelvin scale:
\begin{align*} K &= 22.2^{\circ}C+273.15 \\[5pt] &= 295.4K \end{align*}
So, room temperature is about 295 K.
Health Application: Body temperature
Normal body temperature is defined as being 98.6°F (+/- 1.0°F). To determine body temperature, thermometers can be placed inside or on the surface of the body. The two best methods of obtaining body temperature are placing the thermometer either under the tongue or inside the rectum. Typically, children are capable of holding a thermometer in their mouths around the age of four (have fun before that age).
Fever is defined as body temperature being above 100°F (adults). High fever status occurs at and above 104°F. For adults, these adults should seek medical attention immediately if the fever exceeds 104°F. For children, these values are much lower.
Hyperthermia (inability of the body to regulate heat) occurs when normal body temperature is exceeded. Conditions that can cause hyperthermia are fever (infection), heat stroke, thyroid disorders, heart attack, or traumatic injury. Medications for cancer, arthritis, and thyroid patients can cause the body temperature to rise. Symptoms of hyperthermia include sweating, confusion, nausea, and dizziness.
Hypothermia (exposure to cold environments) occurs when normal body temperature dips below 95.0°F. When this occurs, the affected person(s) should seek immediate medical attention. During hypothermia, the body has problems producing heat. Medical conditions like diabetes, infection, and thyroid dysfunction can cause hypothermia. Watch this video of American Marines attempting to survive extreme environments. Symptoms of this condition involve shivering, confusion, and sluggish behavior.
Treating hyperthermia could involve hydrating a patient. If a fever is due to infection, analgesics (like Tylenol, Advil, aspirin, or Aleve) can help alleviate fever. Placing someone in a cool bath can also relieve symptoms.
To combat hypothermia, one must remove wet clothing, redress in warm materials, and participate in physical movement.
## Heat transfer
Heat is a familiar manifestation of energy. When we touch a hot object, energy flows from the hot object into our fingers, and we perceive that incoming energy as the object being “hot.” Conversely, when we hold an ice cube in our palms, energy flows from our hand into the ice cube, and we perceive that loss of energy as “cold.” In both cases, the temperature of the object is different from the temperature of our hand, so we can conclude that differences in temperatures are the ultimate cause of heat transfer.
Suppose we consider the transfer of heat from the opposite perspective—namely, what happens to a system that gains or loses heat? Generally, the system’s temperature changes. (We will address a few exceptions later.) The greater the original temperature difference, the greater the transfer of heat, and the greater the ultimate temperature change. The relationship between the amount of heat transferred and the temperature change can be written as
$\text{heat} \propto ΔT \label{Eq1}$
where ∝ means “is proportional to” and ΔT is the change in temperature of the system. Any change in a variable is always defined as “the final value minus the initial value” of the variable, so ΔT is TfinalTinitial. In addition, the greater the mass of an object, the more heat is needed to change its temperature. We can include a variable representing mass (m) to the proportionality as follows:
$\text{heat} \propto mΔT \label{Eq2}$
To change this proportionality into an equality, we include a proportionality constant. The proportionality constant is called the specific heat and is commonly symbolized by $$c$$:
$\text{heat} = mcΔT \label{Eq3}$
Every substance has a characteristic specific heat, which is reported in units of cal/g•°C or cal/g•K, depending on the units used to express ΔT. The specific heat of a substance is the amount of energy that must be transferred to or from 1 g of that substance to change its temperature by 1°. Table $$\PageIndex{1}$$ lists the specific heats for various materials.
Table $$\PageIndex{1}$$: Specific Heats of Selected Substances
Substance c (cal/g•°C)
aluminum (Al) 0.215
aluminum oxide (Al2O3) 0.305
benzene (C6H6) 0.251
copper (Cu) 0.092
ethanol (C2H6O) 0.578
hexane (C6H14) 0.394
hydrogen (H2) 3.419
ice [H2O(s)] 0.492
iron (Fe) 0.108
iron(III) oxide (Fe2O3) 0.156
mercury (Hg) 0.033
oxygen (O2) 0.219
sodium chloride (NaCl) 0.207
steam [H2O(g)] 0.488
water [H2O(ℓ)] 1.00
The proportionality constant c is sometimes referred to as the specific heat capacity or (incorrectly) the heat capacity.
The direction of heat flow is not shown in heat = mcΔT. If energy goes into an object, the total energy of the object increases, and the values of heat ΔT are positive. If energy is coming out of an object, the total energy of the object decreases, and the values of heat and ΔT are negative.
Example $$\PageIndex{3}$$
What quantity of heat is transferred when a 150.0 g block of iron metal is heated from 25.0°C to 73.3°C? What is the direction of heat flow?
Solution
We can use heat = mcΔT to determine the amount of heat, but first we need to determine ΔT. Because the final temperature of the iron is 73.3°C and the initial temperature is 25.0°C, ΔT is as follows:
\begin{align*} ΔT = T_{final} − T_{initial} \\[4pt] &= 73.3^oC − 25.0^oC \\[4pt] &= 48.3^oC \end{align*}
The mass is given as 150.0 g, and Table $$\PageIndex{1}$$ gives the specific heat of iron as 0.108 cal/g•°C. Substitute the known values into heat = mcΔT and solve for amount of heat:
$$\mathrm{heat=(150.0\: g)\left(0.108\: \dfrac{cal} {g\cdot {^\circ C}}\right)(48.3^\circ C) = 782\: cal}$$
Note how the gram and °C units cancel algebraically, leaving only the calorie unit, which is a unit of heat. Because the temperature of the iron increases, energy (as heat) must be flowing into the metal.
Exercise $$\PageIndex{3}$$
What quantity of heat is transferred when a 295.5 g block of aluminum metal is cooled from 128.0°C to 22.5°C? What is the direction of heat flow?
Answer
6,700 cal
Example $$\PageIndex{4}$$
A 10.3 g sample of a reddish-brown metal gave off 71.7 cal of heat as its temperature decreased from 97.5°C to 22.0°C. What is the specific heat of the metal? Can you identify the metal from the data in Table $$\PageIndex{1}$$?
Solution
The question gives us the heat, the final and initial temperatures, and the mass of the sample. The value of ΔT is as follows:
ΔT = TfinalTinitial = 22.0°C − 97.5°C = −75.5°C
If the sample gives off 71.7 cal, it loses energy (as heat), so the value of heat is written as a negative number, −71.7 cal. Substitute the known values into heat = mcΔT and solve for c:
−71.7 cal = (10.3 g)(c)(−75.5°C)
$$c \,\mathrm{=\dfrac{-71.7\: cal}{(10.3\: g)(-75.5^\circ C)}}$$
c = 0.0923 cal/g•°C
This value for specific heat is very close to that given for copper in Table $$\PageIndex{1}$$.
Exercise $$\PageIndex{4}$$
A 10.7 g crystal of sodium chloride (NaCl) had an initial temperature of 37.0°C. What is the final temperature of the crystal if 147 cal of heat were supplied to it?
Answer
103.4°C
Notice that water has a very high specific heat compared to most other substances. Water is commonly used as a coolant for machinery because it is able to absorb large quantities of heat (see table above). Coastal climates are much more moderate than inland climates because of the presence of the ocean. Water in lakes or oceans absorbs heat from the air on hot days and releases it back into the air on cool days.
Figure$$\PageIndex{2}$$: This power plant in West Virginia, like many others, is located next to a large lake so that the water from the lake can be used as a coolant. Cool water from the lake is pumped into the plant, while warmer water is pumped out of the plant and back into the lake.
## Summary
• Heat transfer is related to temperature change.
• Thespecific heat of a substance is the amount of energy required to raise the temperature of 1 gram of the substance by $$1^\text{o} \text{C}$$.
## Concept Review Exercise
1. Describe the relationship between heat transfer and the temperature change of an object.
2. Describe what happens when two objects that have different temperatures come into contact with one another.
## Answer
1. Heat is equal to the product of the mass, the change in temperature, and a proportionality constant called the specific heat.
2. The temperature of the hot object decreases and the temperature of the cold object increases as heat is transferred from the hot object to the cold object. The change in temperature of each depends on the identity and properties of each substance.
## Exercises
1. The melting point of mercury is −38.84oC. Convert this value to degrees Fahrenheit and Kelvin.
2. A pot of water is set on a hot burner of a stove. What is the direction of heat flow?
3. Some uncooked macaroni is added to a pot of boiling water. What is the direction of heat flow?
4. How much energy in calories is required to heat 150 g of H2O from 0°C to 100°C?
5. How much energy in calories is required to heat 125 g of Fe from 25°C to 150°C?
6. If 250 cal of heat were added to 43.8 g of Al at 22.5°C, what is the final temperature of the aluminum?
7. If 195 cal of heat were added to 33.2 g of Hg at 56.2°C, what is the final temperature of the mercury?
8. A sample of copper absorbs 145 cal of energy, and its temperature rises from 37.8°C to 41.7°C. What is the mass of the copper?
9. A large, single crystal of sodium chloride absorbs 98.0 cal of heat. If its temperature rises from 22.0°C to 29.7°C, what is the mass of the NaCl crystal?
10. If 1.00 g of each substance in Table 7.3 were to absorb 100 cal of heat, which substance would experience the largest temperature change?
11. If 1.00 g of each substance in Table 7.3 were to absorb 100 cal of heat, which substance would experience the smallest temperature change?
12. Determine the heat capacity of a substance if 23.6 g of the substance gives off 199 cal of heat when its temperature changes from 37.9°C to 20.9°C.
13. What is the heat capacity of gold if a 250 g sample needs 133 cal of energy to increase its temperature from 23.0°C to 40.1°C?
## Answers
1. -37.910F and 234.31 K
2. Heat flows into the pot of water.
3. Heat flows to the macaroni.
4. 15,000 cal
5. 1,690 cal
6. 49.0°C
7. 234°C
8. 404 g
9. 61 g
10. Mercury would experience the largest temperature change.
11. hydrogen (H2)
12. 0.496 cal/g•°C
13. 0.031 cal/g•°C
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https://cran.case.edu/web/packages/Rknots/vignettes/Rknots_vignette.html | # Rknots Package Vignette
## Abstract
From a topological point of view, polymers can be modeled as open polygonal paths. Upon closure, these paths generate topological objects called knots. Multi-component knots are known as links. Rknots provides functions for the topological analysis of knots and links with a particular focus on biological polymers (e.g. proteins).
This vignette is divided in three main parts:
1. Data import and datasets
2. Methods
3. Case study illustrating how to use Rknots to identify knots in proteins.
For more details on the methods, please refer to Comoglio and Rinaldi, 2011 and Comoglio and Rinaldi, 2012.
#### Remarks
Rknots has been developed as a generalized framework. Theoretically, any arbitrary structure compliant with the requirements below can be loaded. Practically, this depends on the complexity of the structure to be analyzed, the task to be performed, and available memory.
## Data import and structure
Rknots deals with knots and links. These are represented as the coordinates of $$N$$ points in the three-dimensional space and a set of integer separators. $$N$$ points in 3D can be naturally represented by a $$N 3$$ matrix, where each row is a point and columns are $$x,y,z$$ coordinates. A knot is entirely defined by its points. However, an integer vector $$S$$ of length $$n-1$$ is required to represent $$n$$-component links. The elements of $$S$$ are called separators and describe the boundaries between components. Particularly, we defined a separator as the index of the edge that if not removed would connect components across.
For example, the Hopf link represented above is defined by an $$8 3$$ matrix and separator $$S={4}$$. The edge that would connect the two components is indicated by the gray dashed line.
### Datasets
Rknots provides two datasets:
1. The Rolfsen table of 250 knots with less than 11 crossings (enumerated according to Rolfsen). Full and minimal stickies representations are stored in the Rolfsen.table and Rolfsen.table.ms datasets, respectively.
library(Rknots)
## Loading required package: rgl
## Loading required package: rSymPy
## Loading required package: rJython
## Loading required package: rJava
## Loading required package: rjson
## Loading required package: bio3d
str( head(Rolfsen.table, 5) )
## List of 5
## $3.1: num [1:48, 1:3] -5 -4.88 -4.39 -3.58 -2.54 ... ##$ 4.1: num [1:70, 1:3] -6.43 -6.26 -5.89 -5.32 -4.56 ...
## $5.1: num [1:70, 1:3] -5.58 -5.85 -5.75 -5.32 -4.66 ... ##$ 5.2: num [1:82, 1:3] -1.191 -0.262 0.803 1.922 3.027 ...
## $6.1: num [1:97, 1:3] -6.9 -6.46 -5.84 -5.05 -4.13 ... head( names(Rolfsen.table) ) ## [1] "3.1" "4.1" "5.1" "5.2" "6.1" "6.2" Note that knots are elements of a named list. Thus, instances can also be accessed by name str( Rolfsen.table['3.1'] ) ## List of 1 ##$ 3.1: num [1:48, 1:3] -5 -4.88 -4.39 -3.58 -2.54 ...
The difference between the full representation of a trefoil knot and its minimal stickies representation is shown below.
2. Coordinates and separators of 130 links up to 4 components, stored in the link.table dataset.
str( head(link.table, 5) )
## List of 5
## $2.2.1:List of 2 ## ..$ points3D: num [1:74, 1:3] -6.3 -5.77 -5.13 -4.4 -3.59 ...
## ..$ends : num 37 ##$ 4.2.1:List of 2
## ..$points3D: num [1:83, 1:3] -0.603 -1.426 -2.171 -2.802 -3.292 ... ## ..$ ends : num 40
## $5.2.1:List of 2 ## ..$ points3D: num [1:79, 1:3] 0.333 -0.598 -1.518 -2.4 -3.213 ...
## ..$ends : num 39 ##$ 6.2.1:List of 2
## ..$points3D: num [1:102, 1:3] 2.131 1.328 0.447 -0.459 -1.338 ... ## ..$ ends : num 50
## $6.2.2:List of 2 ## ..$ points3D: num [1:98, 1:3] -6.57 -6.2 -5.67 -4.98 -4.14 ...
## ..$ends : num 48 head( names(link.table) ) ## [1] "2.2.1" "4.2.1" "5.2.1" "6.2.1" "6.2.2" "6.2.3" Each element of the list has two slots containing link coordinates and separators. We now randomly sample a knot and a link structure to illustrate the main features of the package in the next sections. set.seed(123) knot <- makeExampleKnot(k = TRUE) #a knot link <- makeExampleKnot(k = FALSE) #a link ### Creating objects of class Knot Rknots introduces an S4 class called Knot. An object of class Knot has two mandatory slots: 1. points3D: an $$N 3$$ matrix, where each row is a point and columns are $$x,y,z$$ coordinates of a polygonal knot or link 2. ends: a vector of integers containing the separators of the link components. This slot is by default set to numeric(0) for knots. An new instance of a Knot object can be created either by the class constructor newKnot or with the generic constructor new. knot.cls <- new('Knot', points3D = knot) link.cls <- new('Knot', points3D = link$points3D, ends = link$ends) ( knot.cls <- newKnot(points3D = knot) ) ## An object of class 'Knot' ## Slot points3D: 114 x 3 matrix ## x y z ## [1,] -3.621864 -7.859621 -2.811422 ## [2,] -4.646111 -7.423467 -2.425915 ## [3,] -5.546167 -6.849921 -1.935343 ## [4,] -6.327957 -6.169424 -1.388736 ## [5,] -7.004683 -5.402181 -0.820578 ## [6,] -7.585773 -4.559776 -0.254575 ## [7,] -8.073381 -3.646790 0.290954 ## [8,] -8.457810 -2.662413 0.797152 ## [9,] -8.714276 -1.603682 1.237616 ## [10,] -8.801561 -0.474100 1.570860 ## ........ ........ ........ ## Slot ends: ( link.cls <- newKnot(points3D = link$points3D, ends = link$ends) ) ## An object of class 'Knot' ## Slot points3D: 127 x 3 matrix ## x y z ## [1,] -9.162255 -1.509655 1.829496 ## [2,] -9.245968 -2.659378 1.805300 ## [3,] -9.113029 -3.803538 1.856751 ## [4,] -8.744250 -4.892910 1.956594 ## [5,] -8.136572 -5.871593 2.055047 ## [6,] -7.310295 -6.682295 2.092592 ## [7,] -6.311310 -7.268003 2.009992 ## [8,] -5.216097 -7.575875 1.761636 ## [9,] -4.130063 -7.568088 1.329447 ## [10,] -3.171682 -7.239913 0.731781 ## ........ ........ ........ ## Slot ends: 49 100 Slots can be accessed with the accessors getCoordinates and getEnds, or by subsetting with the [ operator. Direct access with @ is discouraged. head( getCoordinates(knot.cls), 5 ) ## x y z ## [1,] -3.621864 -7.859621 -2.811422 ## [2,] -4.646111 -7.423467 -2.425915 ## [3,] -5.546167 -6.849921 -1.935343 ## [4,] -6.327957 -6.169424 -1.388736 ## [5,] -7.004683 -5.402181 -0.820578 getEnds(knot.cls) ## numeric(0) head( link.cls['points3D'], 5) ## x y z ## [1,] -9.162255 -1.509655 1.829496 ## [2,] -9.245968 -2.659378 1.805300 ## [3,] -9.113029 -3.803538 1.856751 ## [4,] -8.744250 -4.892910 1.956594 ## [5,] -8.136572 -5.871593 2.055047 link.cls['ends'] ## [1] 49 100 Similarly, slots can be modified by the setters setCoordinates, setEnds or using the [<- operator. knot.bu <- knot.cls #copy new.coordinates <- matrix( runif(60), ncol = 3 ) #generate random coordinates setCoordinates(knot.cls) <- new.coordinates #replace knot.cls ## An object of class 'Knot' ## Slot points3D: 20 x 3 matrix ## [,1] [,2] [,3] ## [1,] 0.4089769 0.6405068 0.41372433 ## [2,] 0.8830174 0.9942698 0.36884545 ## [3,] 0.9404673 0.6557058 0.15244475 ## [4,] 0.0455565 0.7085305 0.13880606 ## [5,] 0.5281055 0.5440660 0.23303410 ## [6,] 0.8924190 0.5941420 0.46596245 ## [7,] 0.5514350 0.2891597 0.26597264 ## [8,] 0.4566147 0.1471136 0.85782772 ## [9,] 0.9568333 0.9630242 0.04583117 ## [10,] 0.4533342 0.9022990 0.44220007 ## ........ ........ ........ ## Slot ends: knot.cls <- knot.bu #restore link.bu <- link.cls #copy setEnds(link.cls) <- c(10, 50, 90) #replace separators getEnds(link.cls) ## [1] 10 50 90 link.cls <- link.bu #restore Note that Rknots does not expect the new vector of separators to be of the same length as the original one, i.e. it is possible to change the link type and this is useful when local operations on the link are performed. ## Simplyfing structures and computing invariants The computational cost of polynomial invariants is generally very high. Therefore, structures must be reduced beforehand by reducing the number of points while retaining the topology of the original structure. To this end, two structure reduction algorithms have been implemented in Rknots: 1. the Alexander-Briggs (AB) algorithm based on elementary deformations Alexander and Briggs, 1926; Reidemeister, 1926. 2. the Minimal Structure Reduction (MSR) algorithm Comoglio and Rinaldi, 2011 based on generalized Reidemeister moves. The AB algorithm is very efficient, whereas the MSR algorithm, by working on the knot projection, contains intrinsically more information but is significantly slower. The reduction can be applied directly to coordinates and separators knot.AB <- AlexanderBriggs(points3D = knot, ends = c()) str(knot.AB) ## List of 2 ##$ points3D: num [1:17, 1:3] -3.62 -8.07 -6 6.32 5.09 ...
## $ends : num(0) knot.msr <- msr(points3D = knot, ends = c()) str(knot.msr) ## List of 3 ##$ points3D: num [1:20, 1:3] -3.622 -6.782 2.587 7.076 0.714 ...
## $ends : NULL ##$ M : num [1:19, 1:19] 0 0 0 0 0 0 0 0 0 -1 ...
link.AB <- AlexanderBriggs(points3D = link$points3D, ends = link$ends)
str(link.AB)
## List of 2
## $points3D: num [1:19, 1:3] -9.16 -6.31 2.25 4.3 -2.53 ... ##$ ends : num [1:2] 6 13
link.msr <- msr(points3D = link$points3D, ends = link$ends)
str(link.msr)
## List of 3
## $points3D: num [1:17, 1:3] -9.162 -1.974 4.102 -0.367 -5.506 ... ##$ ends : num [1:2] 6 13
## $M : num [1:16, 1:16] 0 0 0 0 0 0 0 0 0 0 ... or to an object of class Knot with the reduceStructure function. knot.cls.AB <- reduceStructure(knot.cls, algorithm = 'AB' ) knot.cls.MSR <- reduceStructure(knot.cls, algorithm = 'MSR' ) link.cls.AB <- reduceStructure(link.cls, algorithm = 'AB' ) link.cls.MSR <- reduceStructure(link.cls, algorithm = 'MSR' ) link.cls.AB ## An object of class 'Knot' ## Slot points3D: 19 x 3 matrix ## x y z ## [1,] -9.162255 -1.509655 1.829496 ## [2,] -6.311310 -7.268003 2.009992 ## [3,] 2.249036 2.716286 -0.849297 ## [4,] 4.296789 9.491975 0.390813 ## [5,] -2.529795 6.531452 -0.926613 ## [6,] -9.162255 -1.509655 1.829496 ## [7,] -5.362280 3.025527 -1.999231 ## [8,] -6.574879 7.215227 -1.337988 ## [9,] -1.540334 8.744882 1.913969 ## [10,] 5.546724 4.548880 -2.562918 ## ........ ........ ........ ## Slot ends: 6 13 The function msr (and the MSR method) return both the simplified structure, as well as the intersection matrix $$M$$, which contains position and sign of the crossings in the knot/link diagram. This function can also be used to partially reduce structures by controlling the number of iterations (default to 100). The original and simplified structures can be inspected by plotting a knot diagram with plotDiagram. par( mfrow=c(1,2) ) #plotDiagram(knot.AB$points3D, knot.AB$ends, lwd = 2, main = 'Alexander-Briggs') #plotDiagram(knot.msr$points3D, knot.msr$ends, lwd = 2, main = 'MSR') plotDiagram(link.AB$points3D, link.AB$ends, lwd = 2, main = 'Alexander-Briggs') plotDiagram(link.msr$points3D, link.msr$ends, lwd = 2, main = 'MSR') or directly with the plot function is the object is of class Knot. plot(link.cls.AB, lend = 2, lwd = 3, main = 'using par()') ## Case study: Protein knot analysis In this section, we apply Rknots to detect and characterize knots in proteins. Two PDB files are part of the package data and will be used in the following case study: • The Rds3p protein (PDB identifier 2K0A), a member of the U2 snRNP essential for pre-mRNA splicing. Rds3p features a left-handed trefoil knotted structure van Roon et al. 2008 • The first chain (A) of the E. Coli alkaline phosphatase (D153G mutant). This protein presents a structural gap, a potential source of false positives. A protein can be loaded from the file system or fetched from the Protein Data Bank using the loadProtein function, which returns a list of matrices where each element contains the 3D coordinates of a given protein chain. By default, loadProtein performs gap finding for each chain backbone. A cutoff parameter corresponding to the maximum allowed euclidean distance between two consecutive alpha-Carbon residues facilitates a custom definition of a gap. If a distance is greater than cutoff, the chain is split at the corresponding position and subchains are generated. protein <- loadProtein(system.file("extdata/2K0A.pdb", package="Rknots")) ## PDB has multiple END/ENDMDL records ## multi=FALSE: taking first record only ## HEADER METAL BINDING PROTEIN 31-JAN-08 2K0A ## Warning in read.table(text = sapply(raw.atom, split.fields), ## stringsAsFactors = FALSE, : not all columns named in 'colClasses' exist ## Summary of the distance vector ## Min. 1st Qu. Median Mean 3rd Qu. Max. ## 3.744 3.789 3.799 3.800 3.810 3.856 ## No gap found protein<- loadProtein('2K0A') #from the PDB ## Note: Accessing on-line PDB file ## PDB has multiple END/ENDMDL records ## multi=FALSE: taking first record only ## HEADER METAL BINDING PROTEIN 31-JAN-08 2K0A ## Warning in read.table(text = sapply(raw.atom, split.fields), ## stringsAsFactors = FALSE, : not all columns named in 'colClasses' exist ## Summary of the distance vector ## Min. 1st Qu. Median Mean 3rd Qu. Max. ## 3.744 3.789 3.799 3.800 3.810 3.856 ## No gap found str(protein) ## List of 1 ##$ A: num [1:109, 1:3] -9.22 -9.93 -8.36 -11.83 -14.64 ...
## ..- attr(*, "dimnames")=List of 2
## .. ..$: chr [1:109] "2" "11" "18" "29" ... ## .. ..$ : chr [1:3] "x" "y" "z"
The 3D structure of the imported protein and the corresponding backbone model can be then visualized with plotKnot3D, which leverages on the superb graphics of the rgl package. Particularly, any parameter of the rgl functions lines3d and spheres3d can be supplied.
ramp <- colorRamp(c('blue', 'white', 'red'))
pal <- rgb( ramp(seq(0, 1, length = 109)), max = 255)
plotKnot3D(protein$A, colors = list( pal ), lwd = 8, radius = .4, showNC = TRUE, text = TRUE) By setting showNC = TRUE the chain is oriented by labeling the protein N-ter and C-ter, whereas text = TRUE adds a residue number to each point. A snaphot of the 3D plot is illustrated below. To find knots in proteins, a single chain has to be supplied and coerced to a Knot object. The available chains are returned by loadProtein. protein <- newKnot(protein$A)
protein
## An object of class 'Knot'
## Slot points3D: 109 x 3 matrix
## x y z
## 2 -9.225 -24.265 -3.881
## 11 -9.927 -20.804 -5.217
## 18 -8.363 -19.745 -8.522
## 29 -11.829 -18.718 -9.673
## 40 -14.645 -16.690 -8.082
## 64 -12.639 -15.926 -4.953
## 82 -10.105 -13.650 -6.562
## 99 -10.944 -10.485 -4.591
## 119 -9.794 -8.744 -7.783
## 131 -6.918 -7.069 -5.969
## ........ ........ ........
## Slot ends:
Closure and projection can then be performed using closeAndProject. This function applies a Principal Component Analysis on the closed structure to simplify the computation of invariants and for visualization purposes.
protein.cp <- closeAndProject( protein, w = 2 )
par(mfrow = c(1,2))
plot(protein, main = 'original', lwd = 2)
plot(protein.cp, main = 'closed & projected', lwd = 2)
Next, invariants can be computed with
( delta.p <- computeInvariant( protein.cp, invariant = 'Alexander') )
## [1] "-1 + t1 + 1/t1"
( jones.p <- computeInvariant( protein.cp, invariant = 'Jones', skein.sign = -1) )
## [1] "1/t - 1/t^4 + t^(-3)"
( homfly.p <- computeInvariant( protein.cp, invariant = 'HOMFLY', skein.sign = -1) )
## [1] "2*l^2 + l^2*m^2 - l^4"
For simple knots, the knot type can be assigned automatically using getKnotType
getKnotType(polynomial = delta.p, invariant = 'Alexander')
## [1] "Left-handed Trefoil knot (3_1*)" "Right-handed Trefoil knot (3_1)"
getKnotType(polynomial = homfly.p, invariant = 'HOMFLY')
## [1] "Left-handed Trefoil knot (3_1*)"
getKnotType(polynomial = homfly.p, invariant = 'HOMFLY', full.output = TRUE)
## Knot.type HOMFLY
## "Left-handed Trefoil knot (3_1*)" "2*l^2 + l^2*m^2 - l^4"
## Jones Alexander
## "1/t - 1/t^4 + t^(-3)" "-1 + t1 + 1/t1"
## "http://katlas.org/wiki/3_1"
The results indicate the Rds3p protein has a left-handed knot, which can be compared with the right-handed trefoil polynomial in the Rolfsen knot table by means of another Rknots utility:
trefoil <- Rolfsen.table[[1]]
trefoil <- newKnot(trefoil)
( homfly.tr <- computeInvariant(trefoil, 'HOMFLY') )
## [1] "-1/l^4 + 2/l^2 + m^2/l^2"
( homfly.tl <- HOMFLY2mirror(homfly.tr) )
## [1] "2*l^2 + l^2*m^2 - l^4"
identical( homfly.p, homfly.tl )
## [1] TRUE
Finally, if a protein has more than one chain one can interate over all possible chains using lapply. The following code illustrates how to perform this analysis by fetching a protein with two chains from the PDB
processChain <- function(protein, i) {
chain <- newKnot(protein[[i]])
chain <- closeAndProject( chain )
return( computeInvariant(chain, 'HOMFLY') )
}
lengthChain <- function(protein, i) return( nrow(protein[[i]]))
protein <- loadProtein('1AJC', join.gaps = FALSE, cutoff = 7)
## Note: Accessing on-line PDB file
## HEADER NON SPECIFIC MONO-ESTERASE 18-JUL-95 1AJC
## Warning in read.table(text = sapply(raw.atom, split.fields),
## stringsAsFactors = FALSE, : not all columns named in 'colClasses' exist
## Loading chains:
## #aminoacids
## A 446
## B 449
## Summary of the distance vector
## Min. 1st Qu. Median Mean 3rd Qu. Max.
## 3.756 3.793 3.805 3.822 3.817 11.040
## Chain split at position
## 404
## Summary of the distance vector
## Min. 1st Qu. Median Mean 3rd Qu. Max.
## 3.741 3.793 3.805 3.806 3.817 3.864
## No gap found
str(protein)
## List of 3
## $A1: num [1:404, 1:3] 66.9 68.4 67.3 67.4 63.9 ... ## ..- attr(*, "dimnames")=List of 2 ## .. ..$ : chr [1:404] "2" "9" "16" "25" ...
## .. ..$: chr [1:3] "x" "y" "z" ##$ A2: num [1:42, 1:3] 67.8 67.3 66.5 69.4 70.4 ...
## ..- attr(*, "dimnames")=List of 2
## .. ..$: chr [1:42] "2962" "2970" "2976" "2985" ... ## .. ..$ : chr [1:3] "x" "y" "z"
## $B : num [1:449, 1:3] 73.6 74.6 71.9 71.3 73.8 ... ## ..- attr(*, "dimnames")=List of 2 ## .. ..$ : chr [1:449] "3278" "3285" "3292" "3301" ...
## .. ..$: chr [1:3] "x" "y" "z" chains <- names(protein) polynomials <- lapply( 1: length(chains) , function(i) { ifelse(lengthChain(protein, i) > 6, processChain(protein, i), 1) } ) cbind(chains, polynomials) ## chains polynomials ## [1,] "A1" "-1/l^4 + 2/l^2 + m^2/l^2" ## [2,] "A2" "1" ## [3,] "B" "1" The results indicate that the first chain has been split and resulted in a two unknotted subchains. The second chain instead bears a right-handed trefoil knot. Note: by ignoring gap finding, we would have found a knot in the first chain. protein <- loadProtein('1AJC', join.gaps = TRUE) ## Note: Accessing on-line PDB file ## HEADER NON SPECIFIC MONO-ESTERASE 18-JUL-95 1AJC ## Warning in read.table(text = sapply(raw.atom, split.fields), ## stringsAsFactors = FALSE, : not all columns named in 'colClasses' exist ## Loading chains: ## #aminoacids ## A 446 ## B 449 str(protein) ## List of 2 ##$ A: num [1:446, 1:3] 66.9 68.4 67.3 67.4 63.9 ...
## ..- attr(*, "dimnames")=List of 2
## .. ..$: chr [1:446] "2" "9" "16" "25" ... ## .. ..$ : chr [1:3] "x" "y" "z"
## $B: num [1:449, 1:3] 73.6 74.6 71.9 71.3 73.8 ... ## ..- attr(*, "dimnames")=List of 2 ## .. ..$ : chr [1:449] "3278" "3285" "3292" "3301" ...
## .. ..\$ : chr [1:3] "x" "y" "z"
chains <- names(protein)
polynomials <- lapply( 1: length(chains) ,
function(i) {
ifelse(lengthChain(protein, i) > 6, processChain(protein, i), 1) } )
cbind(chains, polynomials)
## chains polynomials
## [1,] "A" "1"
## [2,] "B" "1"
## Session Info
sessionInfo()
## R version 3.3.1 (2016-06-21)
## Platform: x86_64-apple-darwin13.4.0 (64-bit)
## Running under: OS X 10.12 (Sierra)
##
## locale:
## [1] C/en_GB.UTF-8/en_GB.UTF-8/C/en_GB.UTF-8/en_GB.UTF-8
##
## attached base packages:
## [1] stats graphics grDevices utils datasets methods base
##
## other attached packages:
## [1] Rknots_1.3.2 bio3d_2.2-4 rSymPy_0.2-1.1 rJython_0.0-4
## [5] rjson_0.2.15 rJava_0.9-8 rgl_0.96.0
##
## loaded via a namespace (and not attached):
## [1] Rcpp_0.12.7 knitr_1.14 magrittr_1.5 xtable_1.8-2
## [5] R6_2.1.3 stringr_1.1.0 tools_3.3.1 parallel_3.3.1
## [9] grid_3.3.1 htmltools_0.3.5 yaml_2.1.13 digest_0.6.10
## [13] shiny_0.14 formatR_1.4 htmlwidgets_0.7 evaluate_0.9
## [17] mime_0.5 rmarkdown_1.0 stringi_1.1.1 jsonlite_1.0
## [21] httpuv_1.3.3
## References
Adler D. and Murdoch D. rgl: 3D visualization device system (OpenGL).
Alexander J.W. and Briggs G.B. (1926) On types of knotted curves. Ann of Math, 28, 562-586.
Comoglio F. and Rinaldi M. (2011) A Topological Framework for the Computation of the HOMFLY Polynomial and Its Application to Proteins. PLoS ONE 6(4), e18693.
Comoglio F. and Rinaldi M. (2012) Rknots: topological analysis of knotted biopolymers with R. Bioinformatics 28(10), 1400-1401.
Reidemeister K. (1926), Abh Math Sem Univ Hamburg 5: 24-32.
van Roon A.M., Loening N.M., Obayashi E., Yang J.C., Newman A.J., Hernandez H., Nagai K. and Neuhaus D., (2008) Solution structure of the U2 snRNP protein Rds3p reveals a knotted zinc-finger motif, Proc Natl Acad Sci USA, 105, 9621-9626. | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 1, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.3546920120716095, "perplexity": 26246.559019785152}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2021-04/segments/1610703518240.40/warc/CC-MAIN-20210119103923-20210119133923-00083.warc.gz"} |
https://phys.libretexts.org/TextBooks_and_TextMaps/Astronomy_and_Cosmology_TextMaps/Map%3A_Celestial_Mechanics_(Tatum)/5%3A_Gravitational_Field_and_Potential/5.04%3A_The_Gravitational_Fields_of_Various_Bodies/5.4.07%3A_Solid_Cylinder | $$\require{cancel}$$
# 5.4.7: Solid Cylinder
We do this not because it has any particular relevance to celestial mechanics, but because it is easy to do. We imagine a solid cylinder, density $$ρ$$, radius $$a$$, length $$l$$. We seek to calculate the field at a point $$\text{P}$$ on the axis, at a distance $$h$$ from one end of the cylinder (figure $$\text{V.8}$$).
$$\text{FIGURE V.8}$$
The field at $$\text{P}$$ from an elemental disc of thickness $$δz$$ a distance z below P is (from equation 5.4.9)
$δg = Gρδzω. \label{5.4.19} \tag{5.4.19}$
Here $$ω$$ is the solid angle subtended at $$\text{P}$$ by the disc, which is $$2 \pi \left[ 1 - \frac{z}{\left( z^2 + a^2 \right)^{1/2}} \right]$$. Thus the field at $$\text{P}$$ from the entire cylinder is
$g = 2 \pi G ρ \int_h^{l+h} \left[ 1 - \frac{z}{(z^2 + a^2)^{1/2}} \right] dz, \label{5.4.20} \tag{5.4.20}$
or $g = 2 \pi G ρ \left( l - \sqrt{(l+h)^2 + a^2} + \sqrt{h^2+ a^2} \right), \label{5.4.21} \tag{5.4.21}$
or $g = 2\pi G ρ ( l - r_2 + r_1 ). \label{5.4.22} \tag{5.4.22}$
It might also be of interest to express $$g$$ in terms of the height $$y (= \frac{1}{2}l + h)$$ of the point $$\text{P}$$ above the mid-point of the cylinder. Instead of equation $$\ref{5.4.21}$$, we then have
$g = 2 \pi G ρ \left( l - \sqrt{(y + \frac{1}{2}l)^2 + a^2} + \sqrt{(y - \frac{1}{2}l)^2 + a^2} \right) . \label{5.4.23} \tag{5.4.23}$
If the point $$\text{P}$$ is inside the cylinder,at a distance $$h$$ below the upper end of the cylinder, the limits of integration in equation $$\ref{5.4.20}$$ are $$h$$ and $$l − h$$ , and the distance $$y$$ is $$\frac{1}{2}l − h$$. In terms of $$y$$ the gravitational field at $$\text{P}$$ is then
$g = 2 \pi G ρ \left( 2y - \sqrt{(y + \frac{1}{2}l)^2 + a^2} + \sqrt{(y-\frac{1}{2}l)^2 + a^2} \right). \label{5.4.24} \tag{5.4.24}$
In the graph below I have assumed, by way of example, that $$l$$ and $$a$$ are both 1, and I have plotted $$g$$ in units of $$2 \pi Gρ$$ (counting $$g$$ as positive when it is directed downwards) from $$y = −1$$ to $$y = + 1$$. The portion inside the cylinder $$(- \frac{1}{2} ≤ y ≤ \frac{1}{2}l)$$, represented by equation $$\ref{5.4.24}$$, is almost, but not quite, linear. The field at the centre of the cylinder is, of course, zero.
Below, I draw the same graph, but for a thin disc, with $$a = 1$$ and $$l = 0.1$$. We see how it is that the field reaches a maximum immediately above or below the disc, but is zero at the centre of the disc. | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 1, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9527627825737, "perplexity": 134.9496212040022}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.3, "absolute_threshold": 20, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2018-51/segments/1544376827137.61/warc/CC-MAIN-20181215222234-20181216004234-00366.warc.gz"} |
https://www.gradesaver.com/textbooks/math/calculus/calculus-3rd-edition/chapter-11-infinite-series-11-3-convergence-of-series-with-positive-terms-exercises-page-556/33 | ## Calculus (3rd Edition)
Given $$\sum_{n=1}^{\infty}\frac{(\ln n)^{100}}{n^{1.1}}$$ Since for $n\geq1$ \begin{align*} \frac{(\ln n)^{100}}{n^{1.1}}& \leq \frac{\left(n^{0.0001}\right)^{100}}{n^{1.1}}\\ \frac{(\ln n)^{100}}{n^{1.1}} &\leq \frac{n^{0.01}}{n^{1.1}}\\ \frac{(\ln n)^{100}}{n^{1.1}} &\leq \frac{1}{n^{1.09}} \end{align*} Compare with $\displaystyle\sum_{n=1}^{\infty} \frac{1}{n^{1.09}}$, a convergent $p-$series $(p>1)$; then $\displaystyle\sum_{n=1}^{\infty}\frac{(\ln n)^{100}}{n^{1.1}}$ also converges | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 1, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9999867677688599, "perplexity": 29435.857660189165}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2020-05/segments/1579250593994.14/warc/CC-MAIN-20200118221909-20200119005909-00388.warc.gz"} |
https://open.kattis.com/problems/tautology | Kattis
# Tautology
WFF ’N PROOF is a logic game played with dice. Each die has six faces representing some subset of the possible symbols K, A, N, C, E, p, q, r, s, t. A Well-formed formula (WFF) is any string of these symbols obeying the following rules:
• p, q, r, s, and t are WFFs
• if w is a WFF, Nw is a WFF
• if w and x are WFFs, Kwx, Awx, Cwx, and Ewx are WFFs.
The meaning of a WFF is defined as follows:
• p, q, r, s, and t are logical variables that may take on the value 0 (false) or 1 (true).
• K, A, N, C, E mean and, or, not, implies, and equals as defined in the truth table below.
Definitions of K, A, N, C, and E w x Kwx Awx Nw Cwx Ewx 1 1 1 1 0 1 1 1 0 0 1 0 0 0 0 1 0 1 1 1 0 0 0 0 0 1 1 1
A tautology is a WFF that has value 1 (true) regardless of the values of its variables. For example, ApNp is a tautology because it is true regardless of the value of p. On the other hand, ApNq is not, because it has the value 0 for $\text {p}=0$, $\text {q}=1$.
You must determine whether or not a WFF is a tautology.
## Input
Input consists of several test cases. Each test case is a single line containing a WFF with no more than 100 symbols. A line containing 0 follows the last case.
## Output
For each test case, output a line containing “tautology” or “not” as appropriate.
Sample Input 1 Sample Output 1
ApNp
ApNq
0
tautology
not | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8518387079238892, "perplexity": 503.5410288450931}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 20, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2019-35/segments/1566027318986.84/warc/CC-MAIN-20190823192831-20190823214831-00021.warc.gz"} |
https://fredtilley.wordpress.com/2013/01/08/why-the-universe-isnt-soup/ | ## Why The Universe Isn’t Soup
08 Jan
My friend Pete Hague recently answered a question on his blog regarding whether you can touch dark matter. He gave a good, basic explanation using coulomb’s law and then directed people towards me for a fuller solution. So here it is.
As Pete quite rightly explained, the coulomb repulsion of electrons stops atoms from getting too close to each other thus giving the feeling of solidness to objects, but before you even consider bringing atoms together you run into a problem bringing their constituents together.
## Quantisation
If you want to build hydrogen you need a proton and an electron. The negative electron orbits the positive proton and you have an atom. The problem is that everyday experience tells us that the positive-negative attraction would just pull them together until they were touching, leaving no stable structure to the universe. But the experience we have turn out to be just a large scale effect, and at the quantum level things work differently.
In the quantum mechanics of atoms the energies that the bound electrons can have can only take certain values in an analogous way to the strings in a piano only being able to play certain notes. Theses energies in a basic atom are given roughly by
$E_{n} = \frac{-Z^{2}e^{4}m_{e}}{32\pi^{2}\epsilon_{0}^{2}\hbar^{2}n^{2}} = -13.6\frac{Z^{2}}{n^{2}} \text{ eV},$
where Z is the charge of the nucleus of the atom and n ranges from 1 to infinity and at a basic level counts the different energy levels. Each of these energies will have a corresponding orbital radius given by
$r_{n} = \frac{4\pi\epsilon_{0}\hbar^{2}n^{2}}{Ze^{2}m_{e}} =5.29\times 10^{-11}\frac{n^{2}}{Z} \text{ meters}$
So if we take our proton and add an electron to make hydrogen the electron will have to have an energy of -13.6 eV and orbit at a radius of 52.9 picometers. It can’t get any closer as there are no lower energy levels or radii for it to be at.
This gives us our first step to structure, one hydrogen atom has to have a volume of around 620000 cubic picometers, you can’t squash it any smaller. But what about other elements that have more than one electron? What about carbon? For carbon we have Z=6 and 6 electrons, so do they all have energies of -489 eV and orbit at 8.8 picometers? The answer is no.
## Exclusion
The thing that gives atoms and all matter additional structure is the Pauli Exclusion Principle. If we have a system of two particles, A and B, in two possible states, 1 and 2, then the description of the system will be of the form
$\Psi = \phi_{1}(A)\phi_{2}(B)$
We now need to outline two important features of particles;
1. All particles of the same type are indistinguishable from each other.
2. Matter particles are antisymmetric.
From point 1 we don’t know which particle in is which state so the proper description of the system should take into account both possible combinations, this is done in the following way:
$\Psi = \phi_{1}(A)\phi_{2}(B) \pm \phi_{2}(A)\phi_{1}(B)$
From point 2 we have to pick the minus condition. If we were dealing with force particles it would be the plus but for matter the antisymmetry means we have a minus sign.
$\Psi = \phi_{1}(A)\phi_{2}(B) - \phi_{2}(A)\phi_{1}(B)$
So now we have an expression for a system containing two identical particles. What happens if we try to put them in the same state, say ϕ1?
$\Psi = \phi_{1}(A)\phi_{1}(B) - \phi_{1}(A)\phi_{1}(B) = 0$
Therefore you cannot have two identical particles in the same state.
So if we go back to our case of carbon, all 6 electrons are not allowed to just orbit at the same distance with the same energy. We can add the fist electron to the -489eV/8.8pm state, but to add the second electron something will have to be different. In this case it will be spin. You may or may not know that electrons have a quantum property called spin, it can either be up or down and provides a way to get two electron at the same energy and radius as one will be spinning up and the other down meaning the states will be slightly different. As soon as you’ve got the first two electron on that state it is then filled and so you move on to n=2, with a new energy and radius.
At this point things get a lot more complicated and you get more and more ways of getting electrons into the same n level with slightly different states. You have to include things like orbital angular momentum, magnetic effects and Hund’s rules but electron by electron you can build up the entire periodic table which will have the general trend of atoms getting bigger [1].
So through a combination of electrons only being allowed at certain radii with certain energies, and that no two electrons can occupy the same state you end up building bigger and bigger structures that cannot just collapse in on themselves. Then combine this with the electromagnetic explanation that Pete gave and you have the mechanism behind almost all the structure in the universe.
1. Effects from the nucleus and other electrons will cause deviations from the increasing trend as shown here. | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 6, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.7340811491012573, "perplexity": 301.3038339585583}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2018-05/segments/1516084886639.11/warc/CC-MAIN-20180116184540-20180116204540-00743.warc.gz"} |
https://codegolf.stackexchange.com/questions/79008/counting-triangles-with-integer-perimeter/79018 | # Counting triangles with integer perimeter
Mary has given John two sticks of lengths a and b respectively, where a and b are positive integers.
John is very curious.
He would like to know how many triangles with integer perimeter can be formed, by having one additional side.
(This is my first time composing this kind of stupid stories in coding problems, so forgive me if it is too stupid.)
# Specs
• Given two integers a and b, find the number of triangles with integer perimeter that can be formed, by having one additional side.
# Details
• Congruent triangles are congruent.
• Flat triangles are flat out uncounted.
• Zero-sided triangles are counted zero times.
# Scoring
This is . Shortest solution in bytes wins.
# Testcases
a b output
1 2 1
3 3 5
9 7 13
• I like your wording. – Bálint May 1 '16 at 12:43
• Also, is a full program needed or just a function? It makes a big difference in java. Even in javascript. – Bálint May 1 '16 at 12:46
• @Bálint There are default rules for this. – Martin Ender May 1 '16 at 13:16
• For a=1 and b=2, why can't I have two triangles, 1,1,2 and 1,2,2? – Neil May 1 '16 at 13:52
• @Neil 1,1,2 is flat. – Leaky Nun May 1 '16 at 13:53
## Jelly, 3 bytes
«Ḥ’
Try it online!
### Explanation
« min(a,b)
Ḥ *2
’ -1
(Not quite rigorous) proof of correctness:
• Let x = min(a,b) and y = max(a,b), and let z be a potential third side.
• We can't have z ≤ y-x, because for z < y-x the triangle can't be closed and for z = y-x it would be degenerate. See triangle inequality.
• We can't have z ≥ y+x, for the same reasons.
• Every integer z in between is valid and gives a different triangle. That means we've got (y+x) - (y-x) - 1 = 2x - 1 different triangles.
• Could you please prove your algorithm? – Leaky Nun May 1 '16 at 13:03
• Let's say we have a and b, and a>b. The minimum length triangle is a-b+1, the maximum length is a+b-1. The amount of triangles is maximum-minimum+1=a+b-1-(a-b+1)+1=2b-2+1=2b-1 – Bálint May 1 '16 at 13:11
• Could you at least cite the triangle inequality? :) – Leaky Nun May 1 '16 at 13:14
• @KennyLau If you insist... – Martin Ender May 1 '16 at 13:15
## CJam, 7 bytes
l~e<2*(
Test it here.
### Explanation
l~ e# Read and evaluate input.
e< e# min(a,b).
2* e# Double.
( e# Decrement.
For a proof of correctness, see my Jelly answer which uses the same algorithm.
# 05AB1E, 3 bytes
Using @MartinBüttner's algorithm. Code:
·<ß
Explanation:
· # Double the input.
< # Decrement by 1.
ß # Take the smallest value.
Uses CP-1252 encoding. Try it online!.
## Retina, 14 bytes
M!(1+) \1
1
Input and output in unary.
Try it online! (Modified to run multiple decimal test cases at once.)
### Explanation
Still the same approach as my CJam and Jelly answers (the latter contains a proof of correctness), but this time using string processing of unary representations.
M!(1+) \1
This finds min(a,b) by matching the first string of 1s that can be found in both of them. This being a match stage and using the ! the result is actually min(a,b) min(a,b) since the entire match is written back.
1
This simply matches the separating a space and a single 1 and removes them. This leaves a string of 2*min(a,b) - 1 characters, which is the desired result.
## Labyrinth, 20 bytes
Thanks to Sp3000 for some help while golfing this.
<""-}:?:?
"
{
++(!@
Try it online!
### Explanation
It turns out that the 2*min(a,b)-1 approach isn't the shortest in Labyrinth. Instead it's easier to compute (a+b)-|a-b|-1.
Labyrinth primer:
• Labyrinth has two stacks of arbitrary-precision integers, main and aux(iliary), which are initially filled with an (implicit) infinite amount of zeros. I will usually represent these like Main [... a b | c d ...] Aux, where Main grows to the right, Aux grows to the left and ... represents the implicit zeros at the bottom.
• The source code resembles a maze, where the instruction pointer (IP) follows corridors when it can (even around corners). The code starts at the first valid character in reading order, i.e. in the top left corner in this case. When the IP comes to any form of junction (i.e. several adjacent cells in addition to the one it came from), it will pick a direction based on the top of the main stack. The basic rules are: turn left when negative, keep going ahead when zero, turn right when positive. And when one of these is not possible because there's a wall, then the IP will take the opposite direction. The IP also turns around when hitting dead ends.
• The source code can be modified at runtime using <>^v which cyclically shift a row or column of the grid.
The code starts on the < which immediately modifies the source code. This is a common golfing trick in Labyrinth whenever a program starts with a long-ish bit of linear code. Afterwards, the source looks like this, with the IP still on the <:
""-}:?:?<
"
{
++(!@
Since the IP is now in a dead end, it has to start moving left. The linear code does the following:
Op Explanation Stacks
? Read integer a from STDIN. Main [... a | ...] Aux
: Duplicate. Main [... a a | ...] Aux
? Read integer b from STDIN. Main [... a a b | ...] Aux
: Duplicate. Main [... a a b b | ...] Aux
} Move b over to aux. Main [... a a b | b ...] Aux
- Subtract b from a on main. Main [... a (a-b) | b ...] Aux
The code now enters the only nonlinear part of the code which compues -abs(x), (where I'm now using < and v to indicate entry and exit points):
""<
"
v
The " is a no-op (i.e. it does nothing), whereas the multiplies the top of the main stack by -1. Let's go through the three possible cases of control flow:
• If a == b, i.e. a-b is zero, the IP keeps moving west on the first ". Then it hits a corner on the the second " and has to turn south. Again, it keeps moving south on the third " and leaves this 2x2 block. All in all, nothing happens to zeros at all.
• If a > b, i.e. a-b is positive, the IP turns south on the first ". The then switches the top of the main stack to b-a and the IP has to take a turn west. On the next " the top of the stack is now negative, and the IP turns south. Therefore, if the top of the stack is positive, its sign will be negated by this block.
• If a < b, i.e. a-b is negative, then the IP also turns towards the , which now makes it positive. That means the IP turns north on the next no-op. It hits the corner and turns east, and turns south once more so that it reaches the a second time. At this point, the control flow is no different from a positive input, so after applying twice, we're back at a-b which is negative and leaves the loop. Despite doing a lot more stuff, negative inputs are also unaffected by this part of the code.
Now that we've computed -abs(a-b), the remainder of the code is all linear again:
Op Explanation Stacks
[... a -|a-b| | b ...]
{ Move b back to main. [... a -|a-b| b | ...]
+ Add. [... a (-|a-b|+b) | ...]
+ Add. [... (a+b-|a-b|) | ...]
( Decrement. [... (a+b-|a-b|-1) | ...]
! Print as integer. [... | ...]
@ Terminate program.
# Cubix, 18 19 bytes
Not overly short, but a tad more interesting to do due to a lack of a minimum function.
Saved a byte with a big thanks to Martin Büttner
-@IOIU>wu+..U;?;2*
This wraps onto a cube with edge length 2 and ends up looking like this
- @
I O
I U > w u + . .
U ; ? ; 2 * . .
. .
. .
Explanation that hopefully can be followed. Try it here
Getting parameters from STDIN
- # This section gets input, u-turns onto top face,
I # heading up, gets another input and performs a subtraction.
I U # Carries on around the bottom of the cube upto the next part.
Determine least and leaving it at TOS
> w # Hits the ? going up. if TOS is negative turn left, pop stack
U ; ? ; # and U-turn onto bottom face heading back up to ?.
. # If 0 redirect through > and w to ; popping stack, heading right.
. # If positive redirect right to ; which pops TOS
@ # Push 2 onto the stack, multiply, U-turn onto input which
O # gives us -1 for the stack, add it then u-turn to the left
I u + # onto the top face, output the TOS as number and end
U 2 *
• -@IOIU>wu+..U;?;2* saves a byte. – Martin Ender May 3 '16 at 7:29
• @MartinBüttner Thank you very much. Beautiful use of the input to get the -1. I would never have thought of that. – MickyT May 3 '16 at 8:19
# k (8 bytes)
Using the Jelly/CJam algorithm
-1+2*min
e.g.
k)-1+2*(&). 10 10
19
# Java 55 42 bytes
int c(int a,int b){return (a<b?a:b)*2-1);}
• Java has lambdas; use them to save bytes! :) – Leaky Nun May 1 '16 at 13:26
# APL, 6 bytes
1-⍨2×⌊
This is a dyadic function train that accepts integers on the right and left and returns an integer. It uses the 2 min(a, b) - 1 approach.
Try it here (includes all test cases)
# Javascript full program 88 42 bytes
a=prompt();b=prompt();alert((a<b?a:b)*2-1)
I hate prompts, even java is better in that aspect.
# Javascript function 7331 21 bytes
(a,b)=>(a<b?a:b)*2-1
Testable version:
c=(a,b)=>(a<b?a:b)*2-1
var d = prompt("enter first number");
var e = prompt("enter second number");
alert(c(d, e));
Thanks to @Neil for saving 8 bytes. Thanks goes to @MartinBüttner for the algorithm and for saving 1 byte.
• I'll add an answer in java then. (Java is my first language actually...) – Leaky Nun May 1 '16 at 12:48
• What's the space doing in max=a- -b-1;? – Leaky Nun May 1 '16 at 12:48
• Why not use a lambda? You can always use functions instead of full programs unless explicitly forbidden. – Denker May 1 '16 at 12:48
• @DenkerAffe I always work on full programs before going on to lamdas, I did that one too. – Bálint May 1 '16 at 12:51
• @KennyLau If I don't put it there, it throws a syntax error, as -- is the decrement operator. doing a- -b casts both of them to numbers, then subtracts the negative of b from a, thus it's doing the same as adding it. – Bálint May 1 '16 at 12:52
## Actually, 3 bytes
mτD
This uses the same 2*min(a,b)-1 approach that basically every other solutions uses. Each operation (minimum, double, decrement) is its own single-byte command.
# J, 7 bytes
1-~2*<.
This is a tacit verb.
1-~2*<.
1-~ reflexive minus (i.e. R - 1)
2* double
<. lesser of
# Jolf, 4 bytes
m±♀j
Replace ♀ with a literal \x12 byte, or try it here!
## Explanation
m±♀j
♀j min of j and implicit input
m± 2*(^)-1
# PHP 36 bytes
function($a,$b){echo min($a,$b)*2-1}
Thanks goes to @MartinBüttner for the algorithm
C# 6.0 - 34 bytes
int a(int b,int c)=>(b<c?b:c)*2-1;
• Wow, C# has lambdas?! :o – Leaky Nun May 2 '16 at 6:37
• Unbalanced parentheses... – Leaky Nun May 2 '16 at 6:37
• @KennyLau Thanks for telling. It's fixed now :). And yes, C# does have lambdas. C# 6.0 allows named functions to have an lambda expressions their bodies. This saved me from using the 'return' keyword and brackets. – Yytsi May 2 '16 at 18:54 | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.3141174018383026, "perplexity": 4176.147443410237}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2020-24/segments/1590348509972.80/warc/CC-MAIN-20200606031557-20200606061557-00174.warc.gz"} |
https://byjus.com/commerce/tr-jain-and-vk-ohri-solutions-class-11-statistics-for-economics-chapter-10-measures-of-central-tendency-median-and-mode/ | # T.R. Jain and V.K. Ohri Solutions for Class 11 Statistics for Economics Chapter 10 - Measures of Central Tendency- Median and Mode
T.R. Jain and V.K. Ohri Solutions for Class 11 Statistics for Economics Chapter 10 – Measures of Central Tendency- Median and Mode is regarded as an important concept to be studied thoroughly by the students. Here, we have provided T.R. Jain and V.K. Ohri Solutions for Class 11.
Board CBSE Class Class 11 Subject Statistics for Economics Chapter Chapter 10 Chapter Name Measures of Central Tendency- Median and Mode Number of questions solved 04 Category T.R. Jain and V.K. Ohri
Chapter 10 -Measures of Central Tendency- Median and Mode covers the below-mentioned concepts:
• Median
• How to find the median value?
• Missing frequency
• Graphic determination of the median
• Partition value: Quartile
## T.R. Jain and V.K. Ohri Solutions for Class 11 Statistics Economics Chapter 10 – Measures of Central Tendency- Median and Mode
### Question 1
The following series show marks in statistics of 9 students in class 11. Find the median marks.
Marks 22 16 18 13 15 19 17 20 23
Solution:
The data is first arranged in the ascending order:
S.no. Marks 1 13 2 15 3 16 4 17 5 18 6 19 7 20 8 22 9 23 N = 9
$M\, =\, Size\, of\,\left (\frac{N\,+ 1}{2} \right)th\, item$ $=\, Size\, of\, \left (\frac{9\, +\, 1}{2} \right)th\, item$
= Size of 5th item = 18
Hence, Median = 18
### Question 2
The following table gives the marks obtained by some students. Calculate the median marks obtained by the students.
Marks 0-5 5-10 10-15 15-20 20-25 25-30 30-35 35-40 40-45 Number of students 6 12 17 30 10 10 8 5 2
Solution:
Marks Frequency (f) Cumulative Frequency 0-5 6 6 5-10 12 18 10-15 17 35(c.f.) (l1)15-20 30 (f) 65 20-25 10 75 25-30 10 85 30-35 8 93 35-40 5 98 40-45 2 100 = N = 100
M = Size of $\left (\frac{N}{2}\right)th\, item$
= Size of $\left (\frac{100}{2}\right)th\, item$ = Size of 50th item
50th item lies in 65th cumulative frequency and the corresponding median class is 15-20.
$M = l1\, +\, \frac{N/2\, -\, c.f.}{f}\times i$
= $=\, 15\, +\, \frac{100/2\, -\, 35\times 5}{30}$
= $=\, 15\, +\, \frac{15-35}{30}\times 5\, =\, 15\, +\, \frac{15}{30\times 5}$
= 15 + 2.5 = 17.5
Median = 17.5 marks
### Question 3
Find the mode from the following data:
8, 10, 5, 8, 12, 7, 8, 9, 11, 7
Solution:
Arrange the series in an ascending order as:
5, 7, 7, 8, 8, 8, 9, 10, 11, 12
An inspection of the series shows that the values 8 occurs most frequency in the series.
Hence, Mode (Z) = 8
### Question 4
Calculate the mode from the following data:
Wages (₹) 0-5 5-10 10-15 15-20 20-25 25-30 30-35 Number of workers 3 7 15 30 20 10 5
Solution:
Wages (₹) Frequency (f) 0-5 3 5-10 7 10-15 15 (f0) (ll) 15-20 30 (f1) 20-25 20 (f2) 25-30 10 30-35 5
Since the series is regular, we may not do grouping for the location of the model group. By inspection, the modal class is 15-20.
Z = l1 $+\, \frac{f1-f0}{2f1\, -\, f0\,- f2}\times i$
Here, l1 = 15, f1 = 30, f0 = 15, f2 = 20, i = 5
Substituting the values, we get,
$Z\, =\, 15\, +\, \frac{30\, 15}{2\left(30 \right)-15-20}\, \times 5$ $=\, 15+\frac{15}{60-35}\times 5$ $=\, 15+\frac{15}{25}\times 5$
= 15+3=18
Thus, Mode = 18
The above-provided solutions are considered to be the best solutions for Statistics for Economics Class 11 T.R. Jain and V.K. Ohri Solutions for Chapter 10 – Measures of Central Tendency- Median and Mode. Stay tuned to BYJU’S to learn more and score well in the upcoming board examinations.
Important Topics in Economics: | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.41956549882888794, "perplexity": 2337.515019036583}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2020-29/segments/1593655889877.72/warc/CC-MAIN-20200705215728-20200706005728-00492.warc.gz"} |
https://juliamolsim.github.io/DFTK.jl/dev/examples/gross_pitaevskii_2D/ | # Gross-Pitaevskii equation with magnetism
We solve the 2D Gross-Pitaevskii equation with a magnetic field. This is similar to the previous example (Gross-Pitaevskii equation in one dimension), but with an extra term for the magnetic field. We reproduce here the results of https://arxiv.org/pdf/1611.02045.pdf Fig. 10
using DFTK
using StaticArrays
using Plots
Unit cell. Having one of the lattice vectors as zero means a 2D system
a = 15
lattice = a .* [[1 0 0.]; [0 1 0]; [0 0 0]];
Confining scalar potential, and magnetic vector potential
pot(x, y, z) = ((x - a/2)^2 + (y - a/2)^2)/2
ω = .6
Apot(x, y, z) = ω * @SVector [y - a/2, -(x - a/2), 0]
Apot(X) = Apot(X...);
Parameters
Ecut = 20 # Increase this for production
η = 500
C = η/2
α = 2
n_electrons = 1; # Increase this for fun
Collect all the terms, build and run the model
terms = [Kinetic(),
ExternalFromReal(X -> pot(X...)),
PowerNonlinearity(C, α),
Magnetic(Apot),
]
model = Model(lattice; n_electrons=n_electrons,
terms=terms, spin_polarization=:spinless) # "spinless electrons"
basis = PlaneWaveBasis(model, Ecut, kgrid=(1, 1, 1))
scfres = direct_minimization(basis, tol=1e-5) # Reduce tol for production
heatmap(scfres.ρ[:, :, 1, 1], c=:blues) | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.6554246544837952, "perplexity": 9282.573208597581}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2021-31/segments/1627046152000.25/warc/CC-MAIN-20210726031942-20210726061942-00566.warc.gz"} |
https://live-www.tobiidynavox.com/es/Soporte-capacitacion/faq-from-salesforce/what-folders-get-backed-up-automatically-on-i-seriesi-series-devices/?MarketPopupClicked=true | What folders get backed up automatically on I-Series/I-Series+ devices?
All Tobii Dynavox I-Series and/or I-Series+ devices are preconfigured to run a backup script on a regular schedule. The backup script copies important files and folders to the SD card installed in the unit. Below you'll find a description of the files that are included in the backup. Some files are excluded because of their size since the SD card's size is limited (32GB).
I-Series Classic
• All files under %programdata%\Tobii
• All files under %programdata%\Tobii Dynavox
• All files under %programdata%\Viking Software
• All files under %appdata%\Viking Software
• All files under %appdata%\Dynavox
• All files under %appdata%\Tobii
• All files under %appdata%\Tobii Dynavox
• Files under C:\Users\TobiiUser\Documents
I-Series+ with Windows 8.1 or Windows 10 Home
• All files under %programdata%\Tobii Dynavox
• All files under %appdata%\Tobii Dynavox
I-Series+ with Windows 10 Professional
• Documents
• Documents\Communicator 5
• Documents\VS Communicator 4
• %programdata%\Viking Software
• Pictures
• %programdata%\Tobii Dynavox
• %programdata%\Tobii excluding ServiceLog files
• %appdata%\Viking Software
• %appdata%\tobii
• %appdata%\Dynavox\Compass excluding any files in the backups folder over 400Mb
Files are backed up according to a priority list. Image files have the lowest priority (backed up last). If the SD-card does not have sufficient space some files will not be backed up (according to priority).
The backup is scheduled to run every Sunday at 15:00 (3:00pm). If the device is switched off at the scheduled time the backup task will run as soon as possible (next time the device is turned on). Three backups are stored, which means that the SD cards will contain backups from the three previous weeks. The backups are stored under Q:\backup, in folders named after the date of the backup. | {"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8334155082702637, "perplexity": 12215.421301088089}, "config": {"markdown_headings": false, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 5, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2021-04/segments/1610703538741.56/warc/CC-MAIN-20210123222657-20210124012657-00387.warc.gz"} |
https://math.stackexchange.com/questions/3017475/is-there-a-closed-form-for-the-sum-of-the-cubes-of-the-binomial-coefficients | # Is there a closed form for the sum of the cubes of the binomial coefficients?
We know that $$\sum_{k=0}^n \binom{n}{k} = 2^n\;\; \text{ and }\;\; \sum_{k=0}^n \binom{n}{k}^2 = \binom{2n}{n}$$ hold for all $$n\in \mathbb{N}_0$$. Now I tried to find a similar expression for $$\sum_{k=0}^n \binom{n}{k}^3$$ but didn't get anywhere at all. What I found were only asymptotic estimates (see Sum of cubes of binomial coefficients or Asymptotics of $$\sum_{k=0}^{n} {\binom n k}^a$$).
Now is there a closed form for this sum or, what would be even better, for $$\sum_{k=0}^n \binom{n}{k}^\alpha$$ with any $$\alpha \in \mathbb{N}_0$$?
These numbers are called the Franel Numbers. It's proven in (Petkovšek, M., Wilf, H. and Zeilberger, D. (1996). A=B. Wellesley, MA: A K Peters. p. 160) that there is no closed form for these numbers, in terms of the sum of a fixed number of hypergeometric terms.
However, as @Robert_Israel points out, the expression could possibly be represented by different types of closed form.
• ... if "closed form" is defined as "the sum of a fixed number of hypergeometric terms". There could be other types of "closed form". – Robert Israel Nov 28 '18 at 18:24
• @Robert Was just thinking that. Thanks for the suggestion. – Jam Nov 28 '18 at 18:26
The binomial coefficient for a given pair of $$n \geq k \geq 0$$ integers can be expressed in terms of a Pochhammer symbol as the following.
$$\binom n k = \frac{(-1)^k(-n)_k} {k!}.$$
The expression is valid even if $$n$$ is an arbitrary real number.
Here we note two things.
1. The Pochhammer symbol $$(-n)_k$$ is zero, if $$n \geq 0$$ and $$k > -n$$.
2. The factorial $$k!$$ can be written as $$(1)_k$$.
Using these observations, we can express your sums in terms of a generalized hypergeometric function $$_pF_q$$ as the following. For the sum of the binomial coefficients, we have
$$\sum_{k=0}^n \binom n k = \sum_{k=0}^n \frac{(-1)^k(-n)_k}{k!} = \sum_{k=0}^\infty (-n)_k{\frac{(-1)^k}{k!}} = {_1F_0}\left({{-n}\atop{-}}\middle|\,-1\right).$$ For the sum the square of the binomial coefficients, we have $$\sum_{k=0}^n {\binom n k}^2 = \sum_{k=0}^n \left(\frac{(-1)^k(-n)_k}{k!}\right)^2 = \sum_{k=0}^\infty \frac{\left((-n)_k\right)^2}{k!} \cdot \frac{1}{k!} = {_2F_1}\left({{-n, -n}\atop{1}}\middle|\,1\right).$$ And for the sum of the cube of the binomial coefficients $$-$$ also known as Franel numbers $$-$$, we have $$\sum_{k=0}^n {\binom n k}^3 = \sum_{k=0}^n \left(\frac{(-1)^k(-n)_k}{k!}\right)^3 = \sum_{k=0}^\infty \frac{\left((-n)_k\right)^3}{(k!)^2} \cdot \frac{(-1)^k}{k!} = {_3F_2}\left({{-n, -n, -n}\atop{1, 1}}\middle|\,-1\right).$$ In general, for a positive integer $$r$$, we have the binomial sum
\begin{align*} \sum_{k=0}^n {\binom n k}^r &= \sum_{k=0}^n \left(\frac{(-1)^k(-n)_k}{k!}\right)^r = \sum_{k=0}^\infty \frac{\left((-n)_k\right)^r}{(k!)^{r-1}} \cdot \frac{(-1)^{rk}}{k!} \\ &= {_rF_{r-1}}\left({{-n, -n, \dots, -n}\atop{1, \dots, 1}}\middle|\,(-1)^r\right). \end{align*} | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 22, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.99530428647995, "perplexity": 270.4483692534213}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2020-29/segments/1593655883439.15/warc/CC-MAIN-20200703215640-20200704005640-00210.warc.gz"} |
http://kzyjc.alljournals.cn/kzyjc/article/abstract/2021-1728 | 1.河南科技大学;2.东北大学
TP181
Multi-Step Sarsa Control Algorithm Based on RBF Neural Network
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1.Henan University of Science and Technology;2.Northeastern University
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For model-free nonlinear system with continuous state space, a multi-step reinforcement learning control algorithm based on RBF neural network is proposed in this paper. Firstly, the neural network is introduced to reinforcement learning system for approximating state-action value function, which is a common solution to the problem of continuous state space expression in reinforcement learning. Then, combined with the eligibility trace mechanism，multi-step algorithm Sarsa($\lambda$) is formed to improve the learning efficiency of the system by recording the experienced states. Finally, softmax strategy is improved by decayed temperature parameter, so as to optimize the selection probability of actions and balance the relationship between exploration and exploitation. The simulation results of MountainCar task show that the proposed algorithm can effectively achieve the model-free control task of continuous nonlinear system through fewer times of training. Compared with the single-step algorithm, the multi-step algorithm takes less average convergent steps to complete the task and perform more stable, which proves that the combination of nonlinear value function approximation and multi-step algorithm has good performance in the control task.
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##### 历史
• 收稿日期:2021-10-09
• 最后修改日期:2021-12-29
• 录用日期:2021-12-30
• 在线发布日期: 2022-02-01
• 出版日期: | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9103330969810486, "perplexity": 2534.8088212713174}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2022-21/segments/1652662534773.36/warc/CC-MAIN-20220521014358-20220521044358-00363.warc.gz"} |
http://mathhelpforum.com/calculus/152015-derivatives-integrals-absolute-values-oh-my.html | # Thread: Derivatives, Integrals, Absolute Values Oh My!
1. ## Derivatives, Integrals, and Absolute Values, Oh My!
This is making me feel quite stupid right now, but I have the following integral that is messing with my head
$\frac{1}{2\gamma} \int_{-\infty}^{\infty}\! \frac{d^2}{dx^2}\left[e^{-\gamma |x - y|}\right] q(y)\, dy$
Where $q:\mathbb{R}\rightarrow\mathbb{R}$ is continuous with compact support.
My first bit of instinct is to split the integral, because I need to know how to take that derivative. So there are two cases $x < y$ and $x>y$, but how do I translate this into the limits of the integral? It seems that I would split it like so
$\frac{1}{2\gamma} \left(\int_{-\infty}^{x}\! \frac{d^2}{dx^2}\left[e^{-\gamma |x - y|}\right] q(y)\, dy + \int_{x}^{\infty}\! \frac{d^2}{dx^2}\left[e^{-\gamma |x - y|}\right] q(y)\, dy\right)$.
$=\frac{1}{2\gamma} \left(\int_{-\infty}^{x}\! \frac{d^2}{dx^2}\left[e^{-\gamma (x - y)}\right] q(y)\, dy + \int_{x}^{\infty}\! \frac{d^2}{dx^2}\left[e^{-\gamma (y - x)}\right] q(y)\, dy\right)$
$=\frac{1}{2\gamma} \left(\int_{-\infty}^{x}\! \gamma^2e^{-\gamma (x - y)} q(y)\, dy + \int_{x}^{\infty}\! \gamma^2 e^{-\gamma (y - x)} q(y)\, dy\right)$
$=\frac{\gamma}{2} \left(\int_{-\infty}^{x}\! e^{-\gamma (x - y)} q(y)\, dy + \int_{x}^{\infty}\! e^{-\gamma (y - x)} q(y)\, dy\right)$
Does this seem correct?
2. Looks good to me so far.
3. I was hoping it didn't. I guess I will post the whole problem.
Show that
$u(x) = \frac{1}{2\gamma}\int_{-\infty}^{\infty} e^{-\gamma |x - y|}q(y)\, dy$
satisfies
$-u''(x) + \gamma^2 u(x) = q(x)$.
What I end up getting in the end is $0 = q(x)$ instead of $q(x) = q(x)$.
Now my question is miscategorized. lol
4. Well, show what you get when you plug in the derivative and the original function u(x) into your DE.
5. $-u'' + \gamma^2 u = -\frac{d^2}{dx^2}\left(\frac{1}{2\gamma}\int_{-\infty}^{\infty}\! e^{-\gamma|x-y|} q(y)\, dy\right) + \gamma^2\left(\frac{1}{2\gamma}\int_{-\infty}^{\infty}\! e^{-\gamma|x-y|} q(y)\, dy\right)$
$= -\frac{1}{2\gamma}\int_{-\infty}^{\infty}\! \frac{d^2}{dx^2}\left[e^{-\gamma|x-y|}\right] q(y)\, dy+ \frac{\gamma}{2}\int_{-\infty}^{\infty}\! e^{-\gamma|x-y|} q(y)\, dy$
$= -\frac{1}{2\gamma}\left(\int_{-\infty}^{x}\! \frac{d^2}{dx^2}\left[e^{-\gamma(x-y)}\right] q(y)\, dy + \int_{x}^{\infty}\! \frac{d^2}{dx^2}\left[e^{-\gamma(y-x)}\right] q(y)\, dy\right) + \frac{\gamma}{2}\left(\int_{-\infty}^{x}\! e^{-\gamma(x-y)} q(y)\, dy + \int_{x}^{\infty}\! e^{-\gamma(y-x)} q(y)\, dy\right)$
$= -\frac{1}{2\gamma}\left(\int_{-\infty}^{x}\! \frac{d^2}{dx^2}\left[e^{-\gamma(x-y)}\right] q(y)\, dy + \int_{x}^{\infty}\! \frac{d^2}{dx^2}\left[e^{-\gamma(y-x)}\right] q(y)\, dy\right) + \frac{\gamma}{2}\left(\int_{-\infty}^{x}\! e^{-\gamma(x-y)} q(y)\, dy + \int_{x}^{\infty}\! e^{-\gamma(y-x)} q(y)\, dy\right)$
$= -\frac{1}{2\gamma}\left(\int_{-\infty}^{x}\! \gamma^2 e^{-\gamma(x-y)} q(y)\, dy + \int_{x}^{\infty}\! \gamma^2 e^{-\gamma(y-x)} q(y)\, dy\right) + \frac{\gamma}{2}\left(\int_{-\infty}^{x}\! e^{-\gamma(x-y)} q(y)\, dy + \int_{x}^{\infty}\! e^{-\gamma(y-x)} q(y)\, dy\right)$
$= -\frac{\gamma}{2}\left(\int_{-\infty}^{x}\! e^{-\gamma(x-y)} q(y)\, dy + \int_{x}^{\infty}\! e^{-\gamma(y-x)} q(y)\, dy\right) + \frac{\gamma}{2}\left(\int_{-\infty}^{x}\! e^{-\gamma(x-y)} q(y)\, dy + \int_{x}^{\infty}\! e^{-\gamma(y-x)} q(y)\, dy\right) = 0$
6. Where did the minus sign out front come from? It's not in post # 3.
Incidentally, I'm thinking that a Dirac delta function is going to show up any minute. I can feel it in my bones.
7. It is now. That was a typo. It is suppose to be $-u''(x) + \gamma^2 u(x) = q(x)$.
EDIT: Maybe the test had a typo? Hmmm.
8. Find the Green's function. That is, solve
$-G''+\gamma^{2}G=\delta(x).$
I'll bet you anything that the Green's function for this DE is $\frac{1}{2\gamma}\,e^{-\gamma|x-y|}.$
At that point, I think you're pretty much done, since you can write the solution as
$u=\int_{-\infty}^{\infty}G(x,y)g(y)\,dy.$
I'll bet that works for you.
9. That might be. It does look like a Green's Function.
10. Whoops. I think the Green's function satisfies
$-G''+\gamma^{2}G=\delta(x-y).$
Try that.
11. I have to come back to this. I have to get through one more test, before the end of the day and I have spent too much time on this problem. Thank you.
12. Ha, I started the next test and it has the same thing attached to a problem with Green's Functions. So I guess that is what I need to do. | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 23, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8634189963340759, "perplexity": 325.61001470346525}, "config": {"markdown_headings": true, "markdown_code": false, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2017-43/segments/1508187825147.83/warc/CC-MAIN-20171022060353-20171022080353-00300.warc.gz"} |
https://research.chalmers.se/publication/71113 | # Electron-Phonon Interactions in Transition Metal Oxides Studied by Resonance Raman Scattering Doktorsavhandling, 2008
In this thesis, studies of strong electron-phonon interactions in a number of transition metal oxides are presented. Two different electron-phonon interaction mechanisms are identified; Franck-Condon scattering and infrared active longitudinal optical (IR LO) two-phonon activation. The main experimental technique used is temperature dependent resonance Raman scattering and the electron-phonon interactions are studied by the resonant effects they cause on the first and higher order Raman active phonon scattering. The mixed transition metal oxide LaFe$_{0.5}$Cr$_{0.5}$O$_{3}$ with orthorhombic perovskite structure has been studied in detail using resonance Raman scattering with incident photon energies between $\hbar\omega$=1.83 ($\lambda$=676 nm) and $\hbar\omega$=4.13 eV ($\lambda$=300 nm) and variable temperatures. It is established that the characteristic Franck-Condon multi-phonon scattering of a local oxygen breathing mode appears as the photon energy is tuned to the Fe-Cr charge transfer gaps. This interpretation is supported by results obtained from LaFe$_{1-x}$Cr$_{x}$O$_{3}$ (0$\leq$x$\leq$1) which show that the Franck-Condon resonance is critically sensitive to the presence of both Fe and Cr ions in the structure and by Sr-doping in La$_{1-x}$Sr$_{x}$Fe$_{0.5}$Cr$_{0.5}$O$_{3-\delta}$ which shows that the Franck-Condon resonance is sensitive to local effects. In addition to the Franck-Condon effect, Fr\"ohlich interaction induced IR LO two-phonon scattering is observed in the perovskites LaFeO$_{3}$ using $\lambda$=515 nm ($\hbar\omega$=2.41 eV) and LaFe$_{0.5}$Cr$_{0.5}$O$_{3}$ using $\lambda$=334 nm ($\hbar\omega$=3.71 eV). Interestingly, these different resonance effects can be made to mix either by an introduction of a small amount of Cr in LaFeO$_{3}$ or by incident photon energy tuning in LaFe$_{0.5}$Cr$_{0.5}$O$_{3}$ The results in the perovskites are complemented by observations in the spin ladder compound Sr$_{14}$Cu$_{24}$O$_{41}$ where an IR LO two-phonon resonance is activated for incident photon energies around the 1.8 eV charge transfer gap. In the spin ladder compound this resonance is linked to the formation of a charge density wave in the copper-oxide ladder layers below T=200 K. In combination, these observations illustrate the complexity of electron-phonon interactions in transition metal oxides and further establish resonance Raman scattering (in particular the higher order phonon scattering) as a sensitive probe of electron-phonon interactions and the relation between local and global effects in correlated material systems.
Franck-Condon
Fr\"ohlich interaction
higher order scattering
perovskite
transition metal oxide
two-phonon
oxygen breathing mode
Raman spectroscopy
KB salen
Opponent: Professor Göran Grimvall, KTH
## Författare
#### Jakob Andreasson
Chalmers, Teknisk fysik, Kondenserade materiens fysik
#### Resonant two-phonon Raman scattering as a probe of hole crystal formation in Sr14?xCaxCu24O41
Physical Review B - Condensed Matter and Materials Physics,; Vol. 74(2006)p. 134502-
Artikel i vetenskaplig tidskrift
Materialteknik
Fysik
Kemi
#### ISBN
978-91-7385-086-5
Doktorsavhandlingar vid Chalmers tekniska högskola. Ny serie: 2767
KB salen
Opponent: Professor Göran Grimvall, KTH | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8641754984855652, "perplexity": 5951.72320370579}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2018-26/segments/1529267864303.32/warc/CC-MAIN-20180621231116-20180622011116-00443.warc.gz"} |
https://worldwidescience.org/topicpages/t/twisted+baby+skyrmion.html | #### Sample records for twisted baby skyrmion
1. Dynamics of baby Skyrmions
International Nuclear Information System (INIS)
Piette, B.M.A.G.; Schroers, B.J.; Zakrzewski, W.J.
1995-01-01
Baby Skyrmions are topological solitons in a (2+1)-dimensional field theory which resembles the Skyrme model in important respects. We apply some of the techniques and approximations commonly used in discussions of the Skyrme model to the dynamics of baby Skyrmions and directly test them against numerical simulations. Specifically we study the effect of spin on the shape of a single baby Skyrmion, the dependence of the forces between two baby Skyrmions on the baby Skyrmions' relative orientation and the forces between two baby Skyrmions when one of them is spinning. ((orig.))
2. Baby Skyrmion chains
International Nuclear Information System (INIS)
Foster, David
2010-01-01
The Baby Skyrmion model is a two-dimensional analogue of the full three-dimensional Skyrme model. It is not just useful for guiding investigations in the Skyrme model, it also has applications in condensed matter physics. Previous results on multi-charged Baby Skyrmion solutions have pointed to a modular structure, comprised of charge two rings and single charge one Skyrmions, which combine to form higher charged structures. In this paper we present alternative numerical solutions that correspond to new finite Baby Skyrmion chains, which have lower energy than those found previously, and are also good candidates for the global minimum energy solutions. We then proceed from the infinite plane, to Baby Skyrmions on a cylinder and then a torus, to obtain the solutions of periodic Baby Skyrmions, of which periodic segments will correspond to sections of large charge Baby Skyrmions in the plane
3. Noncommutative baby Skyrmions
International Nuclear Information System (INIS)
Ioannidou, Theodora; Lechtenfeld, Olaf
2009-01-01
We subject the baby Skyrme model to a Moyal deformation, for unitary or Grassmannian target spaces and without a potential term. In the Abelian case, the radial BPS configurations of the ordinary noncommutative sigma model also solve the baby Skyrme equation of motion. This gives a class of exact analytic noncommutative baby Skyrmions, which have a singular commutative limit but are stable against scaling due to the noncommutativity. We compute their energies, investigate their stability and determine the asymptotic two-Skyrmion interaction.
4. Easy plane baby Skyrmions
Science.gov (United States)
Jäykkä, Juha; Speight, Martin
2010-12-01
The baby Skyrme model is studied with a novel choice of potential, V=(1)/(2)ϕ32. This “easy plane” potential vanishes at the equator of the target two-sphere. Hence, in contrast to previously studied cases, the boundary value of the field breaks the residual SO(2) internal symmetry of the model. Consequently, even the unit charge Skyrmion has only discrete symmetry and consists of a bound state of two half lumps. A model of long-range inter-Skyrmion forces is developed wherein a unit Skyrmion is pictured as a single scalar dipole inducing a massless scalar field tangential to the vacuum manifold. This model has the interesting feature that the two-Skyrmion interaction energy depends only on the average orientation of the dipoles relative to the line joining them. Its qualitative predictions are confirmed by numerical simulations. Global energy minimizers of charges B=1,…,14,18,32 are found numerically. Up to charge B=6, the minimizers have 2B half lumps positioned at the vertices of a regular 2B-gon. For charges B≥7, rectangular or distorted rectangular arrays of 2B half lumps are preferred, as close to square as possible.
5. Exact BPS bound for noncommutative baby Skyrmions
International Nuclear Information System (INIS)
Domrin, Andrei; Lechtenfeld, Olaf; Linares, Román; Maceda, Marco
2013-01-01
The noncommutative baby Skyrme model is a Moyal deformation of the two-dimensional sigma model plus a Skyrme term, with a group-valued or Grassmannian target. Exact abelian solitonic solutions have been identified analytically in this model, with a singular commutative limit. Inside any given Grassmannian, we establish a BPS bound for the energy functional, which is saturated by these baby Skyrmions. This asserts their stability for unit charge, as we also test in second-order perturbation theory
6. The dynamics of aloof baby Skyrmions
Energy Technology Data Exchange (ETDEWEB)
Salmi, Petja; Sutcliffe, Paul [Department of Mathematical Sciences, Durham University,Durham DH1 3LE (United Kingdom)
2016-01-25
The aloof baby Skyrme model is a (2+1)-dimensional theory with solitons that are lightly bound. It is a low-dimensional analogue of a similar Skyrme model in (3+1)-dimensions, where the lightly bound solitons have binding energies comparable to nuclei. A previous study of static solitons in the aloof baby Skyrme model revealed that multi-soliton bound states have a cluster structure, with constituents that preserve their individual identities due to the short-range repulsion and long-range attraction between solitons. Furthermore, there are many different local energy minima that are all well-described by a simple binary species particle model. In this paper we present the first results on soliton dynamics in the aloof baby Skyrme model. Numerical field theory simulations reveal that the lightly bound cluster structure results in a variety of exotic soliton scattering events that are novel in comparison to standard Skyrmion scattering. A dynamical version of the binary species point particle model is shown to provide a good qualitative description of the dynamics.
7. The dynamics of aloof baby Skyrmions
Science.gov (United States)
Salmi, Petja; Sutcliffe, Paul
2016-01-01
The aloof baby Skyrme model is a (2+1)-dimensional theory with solitons that are lightly bound. It is a low-dimensional analogue of a similar Skyrme model in (3+1)-dimensions, where the lightly bound solitons have binding energies comparable to nuclei. A previous study of static solitons in the aloof baby Skyrme model revealed that multi-soliton bound states have a cluster structure, with constituents that preserve their individual identities due to the short-range repulsion and long-range attraction between solitons. Furthermore, there are many different local energy minima that are all well-described by a simple binary species particle model. In this paper we present the first results on soliton dynamics in the aloof baby Skyrme model. Numerical field theory simulations reveal that the lightly bound cluster structure results in a variety of exotic soliton scattering events that are novel in comparison to standard Skyrmion scattering. A dynamical version of the binary species point particle model is shown to provide a good qualitative description of the dynamics.
8. Squirming motion of baby skyrmions in nematic fluids.
Science.gov (United States)
Ackerman, Paul J; Boyle, Timothy; Smalyukh, Ivan I
2017-09-22
Skyrmions are topologically protected continuous field configurations that cannot be smoothly transformed to a uniform state. They behave like particles and give origins to the field of skyrmionics that promises racetrack memory and other technological applications. Unraveling the non-equilibrium behavior of such topological solitons is a challenge. We realize skyrmions in a chiral liquid crystal and, using numerical modeling and polarized video microscopy, demonstrate electrically driven squirming motion. We reveal the intricate details of non-equilibrium topology-preserving textural changes driving this behavior. Direction of the skyrmion's motion is robustly controlled in a plane orthogonal to the applied field and can be reversed by varying frequency. Our findings may spur a paradigm of soliton dynamics in soft matter, with a rich interplay between topology, chirality, and orientational viscoelasticity.A skyrmion is a topological object originally introduced to model elementary particles and a baby skyrmion is its two-dimensional counterpart which can be realized as a defect in liquid crystals. Here the authors show that an electric field can drive uniform motion of baby skyrmions in liquid crystals.
Energy Technology Data Exchange (ETDEWEB)
Elliot-Ripley, Matthew; Winyard, Thomas [Department of Mathematical Sciences, Durham University,South Rd, Durham (United Kingdom)
2015-09-01
We study the baby Skyrme model in a pure AdS background without a mass term. The tail decays and scalings of massless radial solutions are demonstrated to take a similar form to those of the massive flat space model, with the AdS curvature playing a similar role to the flat space pion mass. We also numerically find minimal energy solutions for a range of higher topological charges and find that they form concentric ring-like solutions. Popcorn transitions (named in analogy with studies of toy models of holographic QCD) from an n layer to an n+1-layer configuration are observed at topological charges 9 and 27 and further popcorn transitions for higher charges are predicted. Finally, a point-particle approximation for the model is derived and used to successfully predict the ring structures and popcorn transitions for higher charge solitons.
10. Gauged BPS baby Skyrmions with quantized magnetic flux
Science.gov (United States)
2017-06-01
A new type of gauged BPS baby Skyrme model is presented, where the derivative term is just the Schroers current (i.e., gauge invariant and conserved version of the topological current) squared. This class of models has a topological bound saturated for solutions of the pertinent Bogomolnyi equations supplemented by a so-called superpotential equation. In contrast to the gauged BPS baby Skyrme models considered previously, the superpotential equation is linear and, hence, completely solvable. Furthermore, the magnetic flux is quantized in units of 2 π , which allows, in principle, to define this theory on a compact manifold without boundary, unlike all gauged baby Skyrme models considered so far.
11. Magnetic skyrmions
Science.gov (United States)
2018-06-01
Welcome to the special issue of Journal of Magnetism and Magnetic Materials on magnetic skyrmions. We are proud to present, with great pleasure, a timely collection of 9 original research articles on the recent hot topic "magnetic skyrmions" which studies the static and dynamic properties of skyrmions and the methods to control them in a variety of ways, including magnetic field, electric current and applied strain.
12. Antiferromagnetic skyrmions
Science.gov (United States)
Tretiakov, Oleg; Barker, Joseph
Skyrmions are topologically protected entities in magnetic materials which have the potential to be used in spintronics for information storage and processing. However, skyrmions in ferromagnets have some intrinsic difficulties which must be overcome to use them for spintronic applications, such as the inability to move straight along current. We show that skyrmions can also be stabilized and manipulated in antiferromagnetic materials. An antiferromagnetic skyrmion is a compound topological object with a similar but of opposite sign spin texture on each sublattice, which e.g. results in a complete cancelation of the Magnus force. We find that the composite nature of antiferromagnetic skyrmions gives rise to different dynamical behavior, both due to an applied current and temperature effects. O.A.T. and J.B. acknowledge support by the Grants-in-Aid for Scientific Research (Nos. 25800184, 25247056, 25220910 and 15H01009) from the Ministry of Education, Culture, Sports, Science and Technology (MEXT) of Japan and SpinNet.
13. Rotational Symmetry Breaking in Baby Skyrme Models
Science.gov (United States)
Karliner, Marek; Hen, Itay
We discuss one of the most interesting phenomena exhibited by baby skyrmions - breaking of rotational symmetry. The topics we will deal with here include the appearance of rotational symmetry breaking in the static solutions of baby Skyrme models, both in flat as well as in curved spaces, the zero-temperature crystalline structure of baby skyrmions, and finally, the appearance of spontaneous breaking of rotational symmetry in rotating baby skyrmions.
14. Nonexistence of Skyrmion-Skyrmion and Skyrmion-anti-Skyrmion static equilibria
International Nuclear Information System (INIS)
Gibbons, G. W.; Warnick, C. M.; Wong, W. W.
2011-01-01
We consider classical static Skyrmion-anti-Skyrmion and Skyrmion-Skyrmion configurations, symmetric with respect to a reflection plane, or symmetric up to a G-parity transformation, respectively. We show that the stress tensor component completely normal to the reflection plane, and hence its integral over the plane, is negative definite or positive definite, respectively. Classical Skyrmions always repel classical Skyrmions and classical Skyrmions always attract classical anti-Skyrmions and thus no static equilibrium, whether stable or unstable, is possible in either case. No other symmetry assumption is made and so our results also apply to multi-Skyrmion configurations. Our results are consistent with existing analyses of Skyrmion forces at large separation, and with numerical results on Skymion-anti-Skyrmion configurations in the literature which admit a different reflection symmetry. They also hold for the massive Skyrme model. We also point out that reflection symmetric self-gravitating Skyrmions or black holes with Skyrmion hair cannot rest in symmetric equilibrium with self-gravitating anti-Skyrmions.
15. Skyrmions in condensed matter
CERN Document Server
Han, Jung Hoon
2017-01-01
This book summarizes some of the most exciting theoretical developments in the topological phenomena of skyrmions in noncentrosymmetric magnetic systems over recent decades. After presenting pedagogical backgrounds to the Berry phase and homotopy theory, the author systematically discusses skyrmions in the order of their development, from the Ginzburg-Landau theory, CP1 theory, Landau-Lifshitz-Gilbert theory, and Monte Carlo numerical approaches. Modern topics, such as the skyrmion-electron interaction, skyrmion-magnon interaction, and various generation mechanisms of the skyrmion are examined with a focus on their general theoretical aspects. The book concludes with a chapter on the skyrmion phenomena in the cold atom context. The topics are presented at a level accessible to beginning graduate students without a substantial background in field theory. The book can also be used as a text for those who wish to engage in the physics of skyrmions in magnetic systems, or as an introduction to the various theoret...
16. Topics in Skyrmion physics
International Nuclear Information System (INIS)
1986-01-01
The first part of the thesis is concerned with the spectrum of fermions interacting with a topological Skyrmion background field. It is shown that, in contradiction to the usual interpretation of a result obtained with the adiabatic approximation, no fermion charge is localized on the Skyrmion through the mechanism of vacuum polarization. This result is obtained by explicitly solving for the continuum spectrum with a simplified Skyrmion profile. However, the Skyrmion can acquire charge if there is spectral flow across zero energy, and an argument is given for why the adiabatic method gives the correct charge under certain conditions. The implications of this understanding of Skyrmion charge for Skyrmion bags are discussed. The second part of the thesis is an investigation into the phenomenology of Skyrmion-like solitons in the standard electroweak model with a large Higgs mass. Estimates of the masses, couplings, and widths of such solitons are derived. The possibility of a resonance analogous to the rho meson in hadron physics is entertained, and the assumption that this resonance is a soliton-antisoliton bound state is used to estimate that its mass is on the order of a TeV. Unitarity arguments are used to get an estimate for the width of this resonance
17. Skyrmions and Hall viscosity
Science.gov (United States)
Kim, Bom Soo
2018-05-01
We discuss the contribution of magnetic Skyrmions to the Hall viscosity and propose a simple way to identify it in experiments. The topological Skyrmion charge density has a distinct signature in the electric Hall conductivity that is identified in existing experimental data. In an electrically neutral system, the Skyrmion charge density is directly related to the thermal Hall conductivity. These results are direct consequences of the field theory Ward identities, which relate various physical quantities based on symmetries and have been previously applied to quantum Hall systems.
18. The multifaceted skyrmion
CERN Document Server
Rho, Mannque
2010-01-01
This is a sequel to the World Scientific volume edited by Gerald E Brown in 1994 entitled ""Selected Papers"", with Commentary, of 'Tony Hilton Royle Skyrme'. There has been a series of impressive developments in the application of the skyrmion structure to wide-ranging physical phenomena. The first volume was mainly focused on the rediscovery of the skyrmion in 1983 in the context of Quantum Chromodynamics (QCD) and on its striking role in nuclear physics. Since 1994, skyrmions have been found to play an even greater role not only in various aspects of particle physics and astrophysics but al
19. Skyrmions and anomalies
International Nuclear Information System (INIS)
Rho, M.
1987-02-01
The author summarizes the works presented at the meeting on skyrmions and anomalies. He divides the principal issues of this workshop into five categories: QCD effective lagrangians, chiral bags and the Cheshire cat principle, strangeness problem, phenomenology, mathematical structure
20. Investigation of restricted baby Skyrme models
International Nuclear Information System (INIS)
Adam, C.; Romanczukiewicz, T.; Wereszczynski, A.; Sanchez-Guillen, J.
2010-01-01
A restriction of the baby Skyrme model consisting of the quartic and potential terms only is investigated in detail for a wide range of potentials. Further, its properties are compared with those of the corresponding full baby Skyrme models. We find that topological (charge) as well as geometrical (nucleus/shell shape) features of baby Skyrmions are captured already by the soliton solutions of the restricted model. Further, we find a coincidence between the compact or noncompact nature of solitons in the restricted model, on the one hand, and the existence or nonexistence of multi-Skyrmions in the full baby Skyrme model, on the other hand.
1. Very heavy dark Skyrmions
International Nuclear Information System (INIS)
Dick, Rainer
2017-01-01
A dark sector with a solitonic component provides a means to circumvent the problem of generically low annihilation cross sections of very heavy dark matter particles. At the same time, enhanced annihilation cross sections are necessary for indirect detection of very heavy dark matter components beyond 100 TeV. Non-thermally produced dark matter in this mass range could therefore contribute to the cosmic γ-ray and neutrino flux above 100 TeV, and massive Skyrmions provide an interesting framework for the discussion of these scenarios. Therefore a Higgs portal and a neutrino portal for very heavy Skyrmion dark matter are discussed. The Higgs portal model demonstrates a dark mediator bottleneck, where limitations on particle annihilation cross sections will prevent a signal from the potentially large soliton annihilation cross sections. This problem can be avoided in models where the dark mediator decays. This is illustrated by the neutrino portal for Skyrmion dark matter. (orig.)
2. Very heavy dark Skyrmions
Energy Technology Data Exchange (ETDEWEB)
2017-12-15
A dark sector with a solitonic component provides a means to circumvent the problem of generically low annihilation cross sections of very heavy dark matter particles. At the same time, enhanced annihilation cross sections are necessary for indirect detection of very heavy dark matter components beyond 100 TeV. Non-thermally produced dark matter in this mass range could therefore contribute to the cosmic γ-ray and neutrino flux above 100 TeV, and massive Skyrmions provide an interesting framework for the discussion of these scenarios. Therefore a Higgs portal and a neutrino portal for very heavy Skyrmion dark matter are discussed. The Higgs portal model demonstrates a dark mediator bottleneck, where limitations on particle annihilation cross sections will prevent a signal from the potentially large soliton annihilation cross sections. This problem can be avoided in models where the dark mediator decays. This is illustrated by the neutrino portal for Skyrmion dark matter. (orig.)
3. Baby Skyrme models for a class of potentials
International Nuclear Information System (INIS)
Eslami, P.; Zakrzewski, W.; Sarbishaei, M.
2000-01-01
We consider a class of (2+1)- dimensional baby Skyrme models with potentials that have more than one vacuum. These potentials are generalizations of old and new baby Skyrme models; they involve more complicated dependence on φ 3 . We find that when the potential is invariant under φ 3 → -φ 3 the configurations corresponding to the baby Skyrmions lying 'on top of each other' are the minima of the energy. However, when the potential breaks this symmetry the lowest field configurations correspond to separated baby skyrmions. We compute the energy distributions for skyrmions of degrees between one and eight and discuss their geometrical shapes and binding energies. We also compare the 2-skyrmion states for these potentials. Most of our work has been performed numerically with the model being formulated in terms of three real scalar fields (satisfying one constraint)
4. Magnetic bilayer-skyrmions without skyrmion Hall effect
Science.gov (United States)
Zhang, Xichao; Zhou, Yan; Ezawa, Motohiko
2016-01-01
Magnetic skyrmions might be used as information carriers in future advanced memories, logic gates and computing devices. However, there exists an obstacle known as the skyrmion Hall effect (SkHE), that is, the skyrmion trajectories bend away from the driving current direction due to the Magnus force. Consequently, the skyrmions in constricted geometries may be destroyed by touching the sample edges. Here we theoretically propose that the SkHE can be suppressed in the antiferromagnetically exchange-coupled bilayer system, since the Magnus forces in the top and bottom layers are exactly cancelled. We show that such a pair of SkHE-free magnetic skyrmions can be nucleated and be driven by the current-induced torque. Our proposal provides a promising means to move magnetic skyrmions in a perfectly straight trajectory in ultra-dense devices with ultra-fast processing speed.
5. Monopole Black Hole Skyrmions
OpenAIRE
Moss, Ian G; Shiiki, N; Winstanley, E
2000-01-01
Charged black hole solutions with pion hair are discussed. These can be\\ud used to study monopole black hole catalysis of proton decay.\\ud There also exist\\ud multi-black hole skyrmion solutions with BPS monopole behaviour.
6. Scattering of a two skyrmion configuration on potential holes or barriers in a model Landau-Lifshitz equation
International Nuclear Information System (INIS)
Collins, J C; Zakrzewski, W J
2009-01-01
The dynamics of a baby-skyrmion configuration, in a model Landau-Lifshitz equation, was studied in the presence of various potential obstructions. The baby-skyrmion configuration was constructed from two Q = 1 hedgehog solutions to the baby-skyrme model in (2+1) dimensions. The potential obstructions were created by introducing a new term into the Lagrangian which resulted in a localized inhomogeneity in the potential terms' coefficient. In the barrier system, the normal circular path was deformed as the skyrmions traversed the barrier. During the same period, it was seen that the skyrmions sped up as they went over the barrier. For critical values of the barrier height and width, the skyrmions were no longer bound and were free to separate. In the case of a potential hole, the baby skyrmions no longer formed a bound state and moved asymptotically along the axis of the hole. It is shown how to modify the definition of the angular momentum to include the effects of the obstructions, so that it is conserved
7. Pion correlation from Skyrmion--anti-Skyrmion annihilation
International Nuclear Information System (INIS)
1995-01-01
We study two pion correlations from Skyrmion and anti-Skyrmion collision, using the product ansatz and an approximate random grooming method for nucleon projection. The spatial-isospin coupling inherent in the Skyrme model, along with empirical averages, leads to correlations not only among pions of like charges but also among unlike charge types
8. Current-induced rotational torques in the skyrmion lattice phase of chiral magnets
NARCIS (Netherlands)
Everschor, K.; Garst, M.; Duine, R.A.|info:eu-repo/dai/nl/304830127; Rosch, A.
2011-01-01
In chiral magnets without inversion symmetry, the magnetic structure can form a lattice of magnetic whirl lines, a two-dimensional skyrmion lattice, stabilized by spin-orbit interactions in a small range of temperatures and magnetic fields. The twist of the magnetization within this phase gives rise
9. Skyrmions in magnetic multilayers
Energy Technology Data Exchange (ETDEWEB)
Jiang, Wanjun; Chen, Gong; Liu, Kai; Zang, Jiadong; te Velthuis, Suzanne G. E.; Hoffmann, Axel
2017-08-01
Symmetry breaking together with strong spin orbit interaction gives rise to many exciting phenomena within condensed matter physics. A recent example is the existence of chiral spin textures, which are observed in magnetic systems lacking inversion symmetry. These chiral spin textures, including domain walls and magnetic skyrmions, are both fundamentally interesting and technologically promising. For example, they can be driven very efficiently by electrical currents, and exhibit many new physical properties determined by their real-space topological characteristics. Depending on the details of the competing interactions, these spin textures exist in different parameter spaces. However, the governing mechanism underlying their physical behaviors remains essentially the same. In this review article, the fundamental topological physics underlying these chiral spin textures, the key factors for materials optimization, and current developments and future challenges will be discussed. In the end, a few promising directions that will advance the development of skyrmion based spintronics will be highlighted.
10. Topological strength of magnetic skyrmions
Energy Technology Data Exchange (ETDEWEB)
Bazeia, D.; Ramos, J.G.G.S.; Rodrigues, E.I.B.
2017-02-01
This work deals with magnetic structures that attain integer and half-integer skyrmion numbers. We model and solve the problem analytically, and show how the solutions appear in materials that engender distinct, very specific physical properties, and use them to describe their topological features. In particular, we found a way to model skyrmion with a large transition region correlated with the presence of a two-peak skyrmion number density. Moreover, we run into the issue concerning the topological strength of a vortex-like structure and suggest an experimental realization, important to decide how to modify and measure the topological strength of the magnetic structure.
11. Creation of skyrmion through resonance excitation
Energy Technology Data Exchange (ETDEWEB)
Li, Zhi-xiong; Chen, Yi-fu; Zhou, Zhen-wei; Nie, Yao-zhuang; Xia, Qing-lin; Wang, Dao-wei; Guo, Guang-hua, E-mail: guogh@mail.csu.edu.cn
2017-07-01
Highlights: • Intrinsic oscillation modes of skyrmion are studied by using micromagnetic simulation. • Creation of skyrmion through resonant excitation is proposed. • The number of generated skyrmions can be effectively controlled by manipulating the driving field. • Skyrmion lattice in extended film is generated via resonant excitation. - Abstract: Controllable creation of magnetic skyrmions in nanostructures is a prerequisite for the application of skyrmions in spintronics. Here, we propose a new method for the creation of skyrmions. We show by using micromagnetic simulations that the skyrmions can be nucleated by resonantly exciting one of the skyrmion intrinsic oscillation modes. We first studied the dynamics of skyrmion in a ferromagnetic nanodisk with perpendicular anisotropy. One breathing mode and two non-degenerate gyrotropic modes are identified. Then we applied a circular-polarized microwave field to excite the uniformly magnetized nanodisk. When the frequency of the driving field is equal to the eigenfrequency of the skyrmion gyrotropic mode, stable skyrmions can be created from the initial uniform state. The number of skyrmions can be effectively controlled by appropriately choosing the duration of the driving field or tuning the field amplitude.
12. Skyrmion creation and annihilation by spin waves
International Nuclear Information System (INIS)
Liu, Yizhou; Yin, Gen; Lake, Roger K.; Zang, Jiadong; Shi, Jing
2015-01-01
Single skyrmion creation and annihilation by spin waves in a crossbar geometry are theoretically analyzed. A critical spin-wave frequency is required both for the creation and the annihilation of a skyrmion. The minimum frequencies for creation and annihilation are similar, but the optimum frequency for creation is below the critical frequency for skyrmion annihilation. If a skyrmion already exists in the cross bar region, a spin wave below the critical frequency causes the skyrmion to circulate within the central region. A heat assisted creation process reduces the spin-wave frequency and amplitude required for creating a skyrmion. The effective field resulting from the Dzyaloshinskii-Moriya interaction and the emergent field of the skyrmion acting on the spin wave drive the creation and annihilation processes
13. Rational maps, monopoles and skyrmions
International Nuclear Information System (INIS)
Houghton, C.J.; Manton, N.S.
1998-01-01
We discuss the similarities between BPS monopoles and skyrmions, and point to an underlying connection in terms of rational maps between Riemann spheres. This involves the introduction of a new ansatz for Skyrme fields. We use this to construct good approximations to several known skyrmions, including all the minimal energy configurations up to baryon number nine, and some new solutions such as a baryon number seventeen Skyrme field with the truncated icosahedron structure of a buckyball. The new approach is also used to understand the low-lying vibrational modes of skyrmions, which are required for quantization. Along the way we discover an interesting Morse function on the space of rational maps which may be of use in understanding the Sen forms on the monopole moduli spaces. (orig.)
14. Twisted light
CSIR Research Space (South Africa)
Forbes, A
2010-12-01
Full Text Available Research at the Mathematical Optics Group uses "twisted" light to study new quatum-based information security systems. In order to understand the structure of "twisted" light, it is useful to start with an ordinary light beam with zero twist, namely...
15. Dynamics of current induced nano-skyrmions
Energy Technology Data Exchange (ETDEWEB)
Natarajan, Kanimozhi; Rajamani, Amuda, E-mail: amuacademics@gmail.com; Arumugam, Brinda
2017-08-01
Highlights: • We have revised and organised section II. • The expression for H{sub eff} is now expressed clearly. • We have added Appendix which explains the derivation of the solution and the occurrence of the oscillatory factor. - Abstract: The dynamics of magnetic skyrmions is investigated in a composite free layer spin valve nano pillar for different coupling mechanisms in the absence of Dzyaloshinski-Moriya Interaction (DMI). Nano meter sized skyrmions and anti skyrmions are trapped with different helices in the free layer. The spin polarised current under specific choice of system parameters changes the droplet solitons into skyrmions and anti skyrmions. The current driven dynamics is studied and the condition at which an isolated skyrmion exists, is reported. We have optimised the current density (J) and spin wave vector (k) for which Skyrmion Hall Effect (SHE) completely vanishes and as a result the velocity, size and shape of skyrmions are preserved. When the coupling between the composite free layers is changed, skyrmion-anti skyrmion pair and radial skyrmion-chiral skyrmion pair emerge. For the specific values of ‘J’ and ‘k’ these pairs show coupled motion along the layer and hence these pairs could also be used as a bit in the data processing and storage devices. Our investigation ascertains that a single material can host all the localised magnetic structures if the current density, spin wave vector and coupling constant are suitably chosen and tuned. This study would really be of fundamental importance owing to the possible applications in information processing and data storage in skyrmion based logic circuits and magnetic sensors.
16. Skyrmion-based multi-channel racetrack
Science.gov (United States)
Song, Chengkun; Jin, Chendong; Wang, Jinshuai; Xia, Haiyan; Wang, Jianbo; Liu, Qingfang
2017-11-01
Magnetic skyrmions are promising for the application of racetrack memories, logic gates, and other nano-devices, owing to their topologically protected stability, small size, and low driving current. In this work, we propose a skyrmion-based multi-channel racetrack memory where the skyrmion moves in the selected channel by applying voltage-controlled magnetic anisotropy gates. It is demonstrated numerically that a current-dependent skyrmion Hall effect can be restrained by the additional potential of the voltage-controlled region, and the skyrmion velocity and moving channel in the racetrack can be operated by tuning the voltage-controlled magnetic anisotropy, gate position, and current density. Our results offer a potential application of racetrack memory based on skyrmions.
17. Magnetic skyrmions: from fundamental to applications
International Nuclear Information System (INIS)
Finocchio, Giovanni; Büttner, Felix; Tomasello, Riccardo; Carpentieri, Mario; Kläui, Mathias
2016-01-01
In this topical review, we will discuss recent advances in the field of skyrmionics (fundamental and applied aspects) mainly focusing on skyrmions that can be realized in thin film structures where an ultrathin ferromagnetic layer (<1 nm) is coupled to materials with large spin–orbit coupling. We review the basic topological nature of the skyrmion spin structure that can entail a stabilization due to the chiral exchange interaction present in many multilayer systems with structural inversion asymmetry. The static spin structures and the dynamics of the skyrmions are also discussed. In particular, we show that skyrmions can be displaced with high reliability and efficiency as needed for the use in devices. We discuss major possible applications, such as memory, microwave oscillators and logic, and combinations of these, making skyrmions very promising candidates for future low power IT devices. (topical review)
18. Reversible Vector Ratchet Effect in Skyrmion Systems
Science.gov (United States)
Ma, Xiaoyu; Reichhardt, Charles; Reichhardt, Cynthia
Magnetic skyrmions are topological non-trivial spin textures found in several magnetic materials. Since their motion can be controlled using ultralow current densities, skyrmions are appealing for potential applications in spintronics as information carriers and processing devices. In this work, we studied the collective transport properties of driven skyrmions based on a particle-like model with molecular dynamics (MD) simulation. Our results show that ac driven skyrmions interacting with an asymmetric substrate provide a realization of a new class of ratchet system, which we call a vector ratchet, that arises due to the effect of the Magnus term on the skyrmion dynamics. In a vector ratchet, the dc motion induced by the ac drive can be described as a vector that can be rotated up to 360 degrees relative to the substrate asymmetry direction. This could represent a new method for controlling skyrmion motion for spintronic applications.
19. Skyrmion physics in Bose-Einstein ferromagnets
NARCIS (Netherlands)
Al Khawaja, U.; Stoof, H.T.C.
2001-01-01
We show that a ferromagnetic Bose-Einstein condensate has not only line-like vortex excitations, but in general, also allows for pointlike topological excitations, i.e., skyrmions. We discuss the thermodynamic stability and the dynamic properties of these skyrmions for both spin-1/2 and
20. The effect of the Magnus force on skyrmion relaxation dynamics
OpenAIRE
Brown, Barton L.; Täuber, Uwe C.; Pleimling, Michel
2018-01-01
We perform systematic Langevin molecular dynamics simulations of interacting skyrmions in thin films. The interplay between Magnus force, repulsive skyrmion-skyrmion interaction and thermal noise yields different regimes during non-equilibrium relaxation. In the noise-dominated regime the Magnus force enhances the disordering effects of the thermal noise. In the Magnus-force-dominated regime, the Magnus force cooperates with the skyrmion-skyrmion interaction to yield a dynamic regime with slo...
1. Tuning the stability and the skyrmion Hall effect in magnetic skyrmions by adjusting their exchange strengths with magnetic disks
Science.gov (United States)
Sun, L.; Wu, H. Z.; Miao, B. F.; Wu, D.; Ding, H. F.
2018-06-01
Magnetic skyrmion is a promising candidate for the future information technology due to its small size, topological protection and the ultralow current density needed to displace it. The applications, however, are currently limited by its narrow phase diagram and the skyrmion Hall effect which prevents the skyrmion motion at high speed. In this work, we study the Dzyaloshinskii-Moriya interaction induced magnetic skyrmion that exchange coupled with magnetic nano-disks utilizing the micromagnetic simulation. We find that the stability and the skyrmion Hall effect of the created skyrmion can be tuned effectively with the coupling strength, thus opens the space to optimize the performance of the skyrmion based devices.
2. Brownian motion of massive skyrmions in magnetic thin films
Energy Technology Data Exchange (ETDEWEB)
Troncoso, Roberto E., E-mail: r.troncoso.c@gmail.com [Centro para el Desarrollo de la Nanociencia y la Nanotecnología, CEDENNA, Avda. Ecuador 3493, Santiago 9170124 (Chile); Núñez, Álvaro S., E-mail: alnunez@dfi.uchile.cl [Departamento de Física, Facultad de Ciencias Físicas y Matemáticas, Universidad de Chile, Casilla 487-3, Santiago (Chile)
2014-12-15
We report on the thermal effects on the motion of current-driven massive magnetic skyrmions. The reduced equation for the motion of skyrmion has the form of a stochastic generalized Thiele’s equation. We propose an ansatz for the magnetization texture of a non-rigid single skyrmion that depends linearly with the velocity. By using this ansatz it is found that the skyrmion mass tensor is closely related to intrinsic skyrmion parameters, such as Gilbert damping, skyrmion-charge and dissipative force. We have found an exact expression for the average drift velocity as well as the mean-square velocity of the skyrmion. The longitudinal and transverse mobility of skyrmions for small spin-velocity of electrons is also determined and found to be independent of the skyrmion mass.
3. Brownian motion of massive skyrmions in magnetic thin films
International Nuclear Information System (INIS)
Troncoso, Roberto E.; Núñez, Álvaro S.
2014-01-01
We report on the thermal effects on the motion of current-driven massive magnetic skyrmions. The reduced equation for the motion of skyrmion has the form of a stochastic generalized Thiele’s equation. We propose an ansatz for the magnetization texture of a non-rigid single skyrmion that depends linearly with the velocity. By using this ansatz it is found that the skyrmion mass tensor is closely related to intrinsic skyrmion parameters, such as Gilbert damping, skyrmion-charge and dissipative force. We have found an exact expression for the average drift velocity as well as the mean-square velocity of the skyrmion. The longitudinal and transverse mobility of skyrmions for small spin-velocity of electrons is also determined and found to be independent of the skyrmion mass
4. Baby Skyrme model and fermionic zero modes
Science.gov (United States)
Queiruga, J. M.
2016-09-01
In this work we investigate some features of the fermionic sector of the supersymmetric version of the baby Skyrme model. We find that, in the background of Bogomol'nyi-Prasad-Sommerfield compact baby Skyrmions, fermionic zero modes are confined to the defect core. Further, we show that, while three Supersymmetry (SUSY) generators are broken in the defect core, SUSY is completely restored outside. We study also the effect of a D-term deformation of the model. Such a deformation allows for the existence of fermionic zero modes and broken SUSY outside the compact defect.
5. Cooperative Charge Pumping and Enhanced Skyrmion Mobility
KAUST Repository
2018-04-06
The electronic pumping arising from the steady motion of ferromagnetic skyrmions is investigated by solving the time evolution of the Schrodinger equation implemented on a tight-binding model with the statistical physics of the many-body problem. It is shown that the ability of steadily moving skyrmions to pump large charge currents arises from their non-trivial magnetic topology, i.e. the coexistence between spin-motive force and topological Hall effect. Based on an adiabatic scattering theory, we compute the pumped current and demonstrate that it scales with the reflection coefficient of the conduction electrons against the skyrmion. Finally, we propose that such a phenomenon can be exploited in the context of racetrack devices, where the electronic pumping enhances the collective motion of the train of skyrmions.
6. Topological phase transitions in the gauged BPS baby Skyrme model
International Nuclear Information System (INIS)
Adam, C.; Naya, C.; Romanczukiewicz, T.; Sanchez-Guillen, J.; Wereszczynski, A.
2015-01-01
We demonstrate that the gauged BPS baby Skyrme model with a double vacuum potential allows for phase transitions from a non-solitonic to a solitonic phase, where the latter corresponds to a ferromagnetic liquid. Such a transition can be generated by increasing the external pressure P or by turning on an external magnetic field H. As a consequence, the topological phase where gauged BPS baby skyrmions exist, is a higher density phase. For smaller densities, obtained for smaller values of P and H, a phase without solitons is reached. We find the critical line in the P,H parameter space. Furthermore, in the soliton phase, we find the equation of state for the baby skyrmion matter V=V(P,H) at zero temperature, where V is the “volume”, i.e., area of the solitons.
7. Topological phase transitions in the gauged BPS baby Skyrme model
Energy Technology Data Exchange (ETDEWEB)
Adam, C.; Naya, C. [Departamento de Física de Partículas, Universidad de Santiago de Compostela andInstituto Galego de Física de Altas Enerxias (IGFAE), Santiago de Compostela, E-15782 (Spain); Romanczukiewicz, T. [Institute of Physics, Jagiellonian University, Lojasiecza 11, Kraków, 30-348 (Poland); Sanchez-Guillen, J. [Departamento de Física de Partículas, Universidad de Santiago de Compostela andInstituto Galego de Física de Altas Enerxias (IGFAE), Santiago de Compostela, E-15782 (Spain); Wereszczynski, A. [Institute of Physics, Jagiellonian University, Lojasiecza 11, Kraków, 30-348 (Poland)
2015-05-29
We demonstrate that the gauged BPS baby Skyrme model with a double vacuum potential allows for phase transitions from a non-solitonic to a solitonic phase, where the latter corresponds to a ferromagnetic liquid. Such a transition can be generated by increasing the external pressure P or by turning on an external magnetic field H. As a consequence, the topological phase where gauged BPS baby skyrmions exist, is a higher density phase. For smaller densities, obtained for smaller values of P and H, a phase without solitons is reached. We find the critical line in the P,H parameter space. Furthermore, in the soliton phase, we find the equation of state for the baby skyrmion matter V=V(P,H) at zero temperature, where V is the “volume”, i.e., area of the solitons.
8. Twisted' electrons
Science.gov (United States)
Larocque, Hugo; Kaminer, Ido; Grillo, Vincenzo; Leuchs, Gerd; Padgett, Miles J.; Boyd, Robert W.; Segev, Mordechai; Karimi, Ebrahim
2018-04-01
Electrons have played a significant role in the development of many fields of physics during the last century. The interest surrounding them mostly involved their wave-like features prescribed by the quantum theory. In particular, these features correctly predict the behaviour of electrons in various physical systems including atoms, molecules, solid-state materials, and even in free space. Ten years ago, new breakthroughs were made, arising from the new ability to bestow orbital angular momentum (OAM) to the wave function of electrons. This quantity, in conjunction with the electron's charge, results in an additional magnetic property. Owing to these features, OAM-carrying, or twisted, electrons can effectively interact with magnetic fields in unprecedented ways and have motivated materials scientists to find new methods for generating twisted electrons and measuring their OAM content. Here, we provide an overview of such techniques along with an introduction to the exciting dynamics of twisted electrons.
9. Antiferromagnetic Skyrmion: Stability, Creation and Manipulation
Science.gov (United States)
Zhang, Xichao; Zhou, Yan; Ezawa, Motohiko
2016-04-01
Magnetic skyrmions are particle-like topological excitations in ferromagnets, which have the topo-logical number Q = ± 1, and hence show the skyrmion Hall effect (SkHE) due to the Magnus force effect originating from the topology. Here, we propose the counterpart of the magnetic skyrmion in the antiferromagnetic (AFM) system, that is, the AFM skyrmion, which is topologically protected but without showing the SkHE. Two approaches for creating the AFM skyrmion have been described based on micromagnetic lattice simulations: (i) by injecting a vertical spin-polarized current to a nanodisk with the AFM ground state; (ii) by converting an AFM domain-wall pair in a nanowire junction. It is demonstrated that the AFM skyrmion, driven by the spin-polarized current, can move straightly over long distance, benefiting from the absence of the SkHE. Our results will open a new strategy on designing the novel spintronic devices based on AFM materials.
10. Oliver Twist
NARCIS (Netherlands)
Dickens, Charles
2005-01-01
Oliver Twist is one of Dickens's most popular novels, with many famous film, television and musical adaptations. It is a classic story of good against evil, packed with humour and pathos, drama and suspense, in which the orphaned Oliver is brought up in a harsh workhouse, and then taken in and
11. Effect of the Magnus force on skyrmion relaxation dynamics
Science.gov (United States)
Brown, Barton L.; Täuber, Uwe C.; Pleimling, Michel
2018-01-01
We perform systematic Langevin molecular dynamics simulations of interacting skyrmions in thin films. The interplay between the Magnus force, the repulsive skyrmion-skyrmion interaction, and the thermal noise yields different regimes during nonequilibrium relaxation. In the noise-dominated regime, the Magnus force enhances the disordering effects of the thermal noise. In the Magnus-force-dominated regime, the Magnus force cooperates with the skyrmion-skyrmion interaction to yield a dynamic regime with slow decaying correlations. These two regimes are characterized by different values of the aging exponent. In general, the Magnus force accelerates the approach to the steady state.
12. Spin eigenmodes of magnetic skyrmions and the problem of the effective skyrmion mass
Science.gov (United States)
Kravchuk, Volodymyr P.; Sheka, Denis D.; Rößler, Ulrich K.; van den Brink, Jeroen; Gaididei, Yuri
2018-02-01
The properties of magnon modes localized on a ferromagnetic skyrmion are studied. Mode eigenfrequencies display three types of asymptotic behavior for large skyrmion radius Rs, namely, ω0∝Rs-2 for the breathing mode and ω-|μ |∝Rs-1 and ω|μ |∝Rs-3 for modes with negative and positive azimuthal quantum numbers, respectively. A number of properties of the magnon eigenfunctions are determined. This enables us to demonstrate that the skyrmion dynamics for a traveling-wave ansatz obeys the massless Thiele equation.
13. Baby Skyrme models without a potential term
Science.gov (United States)
Ashcroft, Jennifer; Haberichter, Mareike; Krusch, Steffen
2015-05-01
We develop a one-parameter family of static baby Skyrme models that do not require a potential term to admit topological solitons. This is a novel property as the standard baby Skyrme model must contain a potential term in order to have stable soliton solutions, though the Skyrme model does not require this. Our new models satisfy an energy bound that is linear in terms of the topological charge and can be saturated in an extreme limit. They also satisfy a virial theorem that is shared by the Skyrme model. We calculate the solitons of our new models numerically and observe that their form depends significantly on the choice of parameter. In one extreme, we find compactons while at the other there is a scale invariant model in which solitons can be obtained exactly as solutions to a Bogomolny equation. We provide an initial investigation into these solitons and compare them with the baby Skyrmions of other models.
14. Skyrmion based microwave detectors and harvesting
International Nuclear Information System (INIS)
Finocchio, G.; Giordano, A.; Ricci, M.; Burrascano, P.; Tomasello, R.; Lanuzza, M.; Puliafito, V.; Azzerboni, B.; Carpentieri, M.
2015-01-01
Magnetic skyrmions are topologically protected states that are very promising for the design of the next generation of ultra-low-power electronic devices. In this letter, we propose a magnetic tunnel junction based spin-transfer torque diode with a magnetic skyrmion as ground state and a perpendicular polarizer patterned as nano-contact for a local injection of the current. The key result is the possibility to achieve sensitivities (i.e., detection voltage over input microwave power) larger than 2000 V/W for optimized contact diameters. We also pointed out that large enough voltage controlled magnetocrystalline anisotropy could significantly improve the sensitivity. Our results can be very useful for the identification of a class of spin-torque diodes with a non-uniform ground state and to understand the fundamental physics of the skyrmion dynamical properties
15. Skyrmion based microwave detectors and harvesting
Energy Technology Data Exchange (ETDEWEB)
Finocchio, G.; Giordano, A. [Department of Mathematical and Computer Sciences, Physical Sciences and Earth Sciences, University of Messina, Viale F. Stagno d' Alcontres 31, 98166 Messina (Italy); Ricci, M.; Burrascano, P. [Department of Engineering, Polo Scientifico Didattico di Terni, University of Perugia, Terni, TR I-50100 (Italy); Tomasello, R.; Lanuzza, M. [Department of Computer Science, Modelling, Electronics and System Science, University of Calabria, via P. Bucci 41C, I-87036 Rende (CS) (Italy); Puliafito, V.; Azzerboni, B. [Department of Engineering, University of Messina, c.da di Dio, I-98166 Messina (Italy); Carpentieri, M. [Department of Electrical and Information Engineering, Politecnico di Bari, via E. Orabona 4, I-70125 Bari (Italy)
2015-12-28
Magnetic skyrmions are topologically protected states that are very promising for the design of the next generation of ultra-low-power electronic devices. In this letter, we propose a magnetic tunnel junction based spin-transfer torque diode with a magnetic skyrmion as ground state and a perpendicular polarizer patterned as nano-contact for a local injection of the current. The key result is the possibility to achieve sensitivities (i.e., detection voltage over input microwave power) larger than 2000 V/W for optimized contact diameters. We also pointed out that large enough voltage controlled magnetocrystalline anisotropy could significantly improve the sensitivity. Our results can be very useful for the identification of a class of spin-torque diodes with a non-uniform ground state and to understand the fundamental physics of the skyrmion dynamical properties.
16. Skyrmion states in thin confined polygonal nanostructures
Science.gov (United States)
Pepper, Ryan Alexander; Beg, Marijan; Cortés-Ortuño, David; Kluyver, Thomas; Bisotti, Marc-Antonio; Carey, Rebecca; Vousden, Mark; Albert, Maximilian; Wang, Weiwei; Hovorka, Ondrej; Fangohr, Hans
2018-03-01
Recent studies have demonstrated that skyrmionic states can be the ground state in thin-film FeGe disk nanostructures in the absence of a stabilising applied magnetic field. In this work, we advance this understanding by investigating to what extent this stabilisation of skyrmionic structures through confinement exists in geometries that do not match the cylindrical symmetry of the skyrmion—such as squares and triangles. Using simulation, we show that skyrmionic states can form the ground state for a range of system sizes in both triangular and square-shaped FeGe nanostructures of 10 nm thickness in the absence of an applied field. We further provide data to assist in the experimental verification of our prediction; to imitate an experiment where the system is saturated with a strong applied field before the field is removed, we compute the time evolution and show the final equilibrium configuration of magnetization fields, starting from a uniform alignment.
17. Writing and deleting single magnetic skyrmions.
Science.gov (United States)
Romming, Niklas; Hanneken, Christian; Menzel, Matthias; Bickel, Jessica E; Wolter, Boris; von Bergmann, Kirsten; Kubetzka, André; Wiesendanger, Roland
2013-08-09
Topologically nontrivial spin textures have recently been investigated for spintronic applications. Here, we report on an ultrathin magnetic film in which individual skyrmions can be written and deleted in a controlled fashion with local spin-polarized currents from a scanning tunneling microscope. An external magnetic field is used to tune the energy landscape, and the temperature is adjusted to prevent thermally activated switching between topologically distinct states. Switching rate and direction can then be controlled by the parameters used for current injection. The creation and annihilation of individual magnetic skyrmions demonstrates the potential for topological charge in future information-storage concepts.
18. BPS Skyrmions as neutron stars
Energy Technology Data Exchange (ETDEWEB)
Adam, C., E-mail: adam@fpaxp1.usc.es [Departamento de Física de Partículas, Universidad de Santiago de Compostela and Instituto Galego de Física de Altas Enerxias (IGFAE), E-15782 Santiago de Compostela (Spain); Naya, C.; Sanchez-Guillen, J.; Vazquez, R. [Departamento de Física de Partículas, Universidad de Santiago de Compostela and Instituto Galego de Física de Altas Enerxias (IGFAE), E-15782 Santiago de Compostela (Spain); Wereszczynski, A. [Institute of Physics, Jagiellonian University, Reymonta 4, Kraków (Poland)
2015-03-06
The BPS Skyrme model has been demonstrated already to provide a physically intriguing and quantitatively reliable description of nuclear matter. Indeed, the model has both the symmetries and the energy–momentum tensor of a perfect fluid, and thus represents a field theoretic realization of the “liquid droplet” model of nuclear matter. In addition, the classical soliton solutions together with some obvious corrections (spin–isospin quantization, Coulomb energy, proton-neutron mass difference) provide an accurate modeling of nuclear binding energies for heavier nuclei. These results lead to the rather natural proposal to try to describe also neutron stars by the BPS Skyrme model coupled to gravity. We find that the resulting self-gravitating BPS Skyrmions provide excellent results as well as some new perspectives for the description of bulk properties of neutron stars when the parameter values of the model are extracted from nuclear physics. Specifically, the maximum possible mass of a neutron star before black-hole formation sets in is a few solar masses, the precise value of which depends on the precise values of the model parameters, and the resulting neutron star radius is of the order of 10 km.
19. Cooperative Charge Pumping and Enhanced Skyrmion Mobility
KAUST Repository
Abbout, Adel; Weston, Joseph; Waintal, Xavier; Manchon, Aurelien
2018-01-01
. It is shown that the ability of steadily moving skyrmions to pump large charge currents arises from their non-trivial magnetic topology, i.e. the coexistence between spin-motive force and topological Hall effect. Based on an adiabatic scattering theory, we
20. Skyrmions with holography and hidden local symmetry
International Nuclear Information System (INIS)
Nawa, Kanabu; Hosaka, Atsushi; Suganuma, Hideo
2009-01-01
We study baryons as Skyrmions in holographic QCD with D4/D8/D8 multi-D brane system in type IIA superstring theory, and also in the nonlinear sigma model with hidden local symmetry. Comparing these two models, we find that the extra dimension and its nontrivial curvature can largely change the role of (axial) vector mesons for baryons in four-dimensional space-time. In the hidden local symmetry approach, the ρ-meson field as a massive Yang-Mills field has a singular configuration in Skyrmion, which gives a strong repulsion for the baryon as a stabilizer. When the a 1 meson is added in this approach, the stability of Skyrmion is lost by the cancellation of ρ and a 1 contributions. On the contrary, in holographic QCD, the ρ-meson field does not appear as a massive Yang-Mills field due to the extra dimension and its nontrivial curvature. We show that the ρ-meson field has a regular configuration in Skyrmion, which gives a weak attraction for the baryon in holographic QCD. We argue that Skyrmion with π, ρ, and a 1 mesons become stable due to the curved extra dimension and also the presence of the Skyrme term in holographic QCD. From this result, we also discuss the features of our truncated-resonance analysis on baryon properties with π and ρ mesons below the cutoff scale M KK ∼1 GeV in holographic QCD, which is compared with other 5D instanton analysis.
1. Interaction of Individual Skyrmions in a Nanostructured Cubic Chiral Magnet
Science.gov (United States)
Du, Haifeng; Zhao, Xuebing; Rybakov, Filipp N.; Borisov, Aleksandr B.; Wang, Shasha; Tang, Jin; Jin, Chiming; Wang, Chao; Wei, Wensheng; Kiselev, Nikolai S.; Zhang, Yuheng; Che, Renchao; Blügel, Stefan; Tian, Mingliang
2018-05-01
We report direct evidence of the field-dependent character of the interaction between individual magnetic skyrmions as well as between skyrmions and edges in B 20 -type FeGe nanostripes observed by means of high-resolution Lorentz transmission electron microscopy. It is shown that above certain critical values of an external magnetic field the character of such long-range skyrmion interactions changes from attraction to repulsion. Experimentally measured equilibrium inter-skyrmion and skyrmion-edge distances as a function of the applied magnetic field shows quantitative agreement with the results of micromagnetic simulations. The important role of demagnetizing fields and the internal symmetry of three-dimensional magnetic skyrmions are discussed in detail.
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3. Exact asymmetric Skyrmion in anisotropic ferromagnet and its helimagnetic application
Energy Technology Data Exchange (ETDEWEB)
Kundu, Anjan, E-mail: anjan.kundu@saha.ac.in
2016-08-15
Topological Skyrmions as intricate spin textures were observed experimentally in helimagnets on 2d plane. Theoretical foundation of such solitonic states to appear in pure ferromagnetic model, as exact solutions expressed through any analytic function, was made long ago by Belavin and Polyakov (BP). We propose an innovative generalization of the BP solution for an anisotropic ferromagnet, based on a physically motivated geometric (in-)equality, which takes the exact Skyrmion to a new class of functions beyond analyticity. The possibility of stabilizing such metastable states in helimagnets is discussed with the construction of individual Skyrmion, Skyrmion crystal and lattice with asymmetry, likely to be detected in precision experiments.
4. Collodion baby
Directory of Open Access Journals (Sweden)
1992-01-01
Full Text Available Collodion baby is a rare congenital disorder characterized by parchment like taught membrane covering the whole body. Other findings in our case include ectropion, eversion of lips, and flattening of nose and ears. Skin biopsy showed features consistant with the diagnosis of collodion baby. The child was treated with supportive measures like antibiotics, intravenous fluids, humidification, and application of emollients.
5. Avalanches and Criticality in Driven Magnetic Skyrmions
Science.gov (United States)
Díaz, S. A.; Reichhardt, C.; Arovas, D. P.; Saxena, A.; Reichhardt, C. J. O.
2018-03-01
We show using numerical simulations that slowly driven Skyrmions interacting with random pinning move via correlated jumps or avalanches. The avalanches exhibit power-law distributions in their duration and size, and the average avalanche shape for different avalanche durations can be scaled to a universal function, in agreement with theoretical predictions for systems in a nonequilibrium critical state. A distinctive feature of Skyrmions is the influence of the nondissipative Magnus term. When we increase the ratio of the Magnus term to the damping term, a change in the universality class of the behavior occurs, the average avalanche shape becomes increasingly asymmetric, and individual avalanches exhibit motion in the direction perpendicular to their own density gradient.
6. Chiral bags, skyrmions and quarks in nuclei
International Nuclear Information System (INIS)
Rho, M.
1984-09-01
Recent developments on an intriguing connection between the quark-bag description of the baryons (nucleons in particular) and the Skyrmion model are discussed in terms of the constraints coming from chiral anomalies. Topics treated are the leaking baryon charge, axial charge and energy density; the role of chiral anomalies; the role of Skyrme's quartic term and the connection to the meson degrees of freedom; and finally some qualitative implications in nuclei. The presentation is purposely descriptive and intuitive instead of mathematically precise
7. The Skyrmions and quarks in nuclei
International Nuclear Information System (INIS)
Rho, M.
1984-08-01
It is proposed that the quark-bag description and the Skyrmion description of baryons are related to each other by quantized parameters. Topology (through a chiral anomaly) plays an important role in bridging the fundamental theory of the strong interactions (QCD) to effective theories. Some consequences on the efforts to see quark degrees of freedom in nuclear matter are discussed. It is suggested that at low energies there will be no ''smoking gun'' evidences for quark presence in nuclei
8. The rotationally improved Skyrmion, or RISKY
International Nuclear Information System (INIS)
Dorey, N.
1995-01-01
The perceived inability of the Skyrme model to reproduce pseudovector pion-baryon coupling has come to be known as the ''Yukawa problem.'' In this talk, we review the complete solution to this problem. The solution involves a new configuration known as the rotationally improved Skyrmion, or ''RISKY,'' in which the hedgehog structure is modified by a small quadrupole distortion. We illustrate our ideas both in the Skyrme model and in a simpler model with a global U(l) symmetry
9. Twisted supersymmetry: Twisted symmetry versus renormalizability
International Nuclear Information System (INIS)
Dimitrijevic, Marija; Nikolic, Biljana; Radovanovic, Voja
2011-01-01
We discuss a deformation of superspace based on a Hermitian twist. The twist implies a *-product that is noncommutative, Hermitian and finite when expanded in a power series of the deformation parameter. The Leibniz rule for the twisted supersymmetry transformations is deformed. A minimal deformation of the Wess-Zumino action is proposed and its renormalizability properties are discussed. There is no tadpole contribution, but the two-point function diverges. We speculate that the deformed Leibniz rule, or more generally the twisted symmetry, interferes with renormalizability properties of the model. We discuss different possibilities to render a renormalizable model.
10. Mermaid baby
Directory of Open Access Journals (Sweden)
N Khan
2010-08-01
Full Text Available We were recently intrigued by a baby born at Kalafong Hospital with fused lower extremities resembling a mermaid, which caused us to search for the background and origin of this entity called sirenomelia.
11. Baby Factory
African Journals Online (AJOL)
Prof
2018-01-24
Jan 24, 2018 ... mass media have the power to easily propagate ideas on social change ... issue of 'baby factory' is becoming everyday news affecting the right of ... according to recent mass media reports, teenage girls and young women are.
12. Systematics of meson-Skyrmion scattering
International Nuclear Information System (INIS)
Mattis, M.P.
1986-02-01
The S-matrix characterizing the scattering of pions from nucleons is calculated in the context of skyrmion models of the nucleon. These are models in which the nucleon is considered a soliton in the field of pions. The spectrum of nucleon and delta resonances in the Skyrme model is calculated and found to be in overall good agreement with Nature. Model-independent sum rules between amplitudes in the same partial wave are derived and examined. An extension of the formalism to the case of three light flavors is presented. 31 refs., 26 figs., 6 tabs
13. Systematics of meson-Skyrmion scattering
Energy Technology Data Exchange (ETDEWEB)
Mattis, M.P.
1986-02-01
The S-matrix characterizing the scattering of pions from nucleons is calculated in the context of skyrmion models of the nucleon. These are models in which the nucleon is considered a soliton in the field of pions. The spectrum of nucleon and delta resonances in the Skyrme model is calculated and found to be in overall good agreement with Nature. Model-independent sum rules between amplitudes in the same partial wave are derived and examined. An extension of the formalism to the case of three light flavors is presented. 31 refs., 26 figs., 6 tabs.
14. Electrical detection of single magnetic skyrmion at room temperature
Directory of Open Access Journals (Sweden)
Riccardo Tomasello
2017-05-01
Full Text Available This paper proposes a protocol for the electrical detection of a magnetic skyrmion via the change of the tunneling magnetoresistive (TMR signal in a three-terminal device. This approach combines alternating spin-transfer torque from both spin-filtering (due to a perpendicular polarizer and spin-Hall effect with the TMR signal. Micromagnetic simulations, used to test and verify such working principle, show that there exists a frequency region particularly suitable for this achievement. This result can be at the basis of the design of a TMR based read-out for skyrmion detection, overcoming the difficulties introduced by the thermal drift of the skyrmion once nucleated.
15. Inflating baby-Skyrme branes in six dimensions
International Nuclear Information System (INIS)
2010-01-01
We consider a six-dimensional brane world model, where the brane is described by a localized solution to the baby-Skyrme model extending in the extra dimensions. The branes have a cosmological constant modeled by inflating four-dimensional slices, and we further consider a bulk cosmological constant. We construct solutions numerically and present evidence that the solutions cease to exist for large values of the brane cosmological constant in some particular case. Then we study the stability of the model by considering perturbation of the gravitational part (resp. baby Skyrmion) with fixed matter fields (resp. gravitational background). Our results indicate that the perturbation equations do not admit localized solutions for certain type of perturbation. The stability analysis can be alternatively seen as leading to a particle spectrum; we give mass estimations for the baby-Skyrme perturbation and for the graviton.
16. Face Centered Cubic and Hexagonal Close Packed Skyrmion Crystals in Centrosymmetric Magnets
Science.gov (United States)
Lin, Shi-Zeng; Batista, Cristian D.
2018-02-01
Skyrmions are disklike objects that typically form triangular crystals in two-dimensional systems. This situation is analogous to the so-called pancake vortices of quasi-two-dimensional superconductors. The way in which Skyrmion disks or "pancake Skyrmions" pile up in layered centrosymmetric materials is dictated by the interlayer exchange. Unbiased Monte Carlo simulations and simple stabilization arguments reveal face centered cubic and hexagonal close packed Skyrmion crystals for different choices of the interlayer exchange, in addition to the conventional triangular crystal of Skyrmion lines. Moreover, an inhomogeneous current induces a sliding motion of pancake Skyrmions, indicating that they behave as effective mesoscale particles.
17. Baby universes
International Nuclear Information System (INIS)
Strominger, A.
1988-01-01
This paper discusses how the subject of baby universes and their effects on spacetime coupling constants is in its infancy and rapidly developing. The subject is based on the non-existent (even by physicists' standards) Euclidean formulation of quantum gravity, and it is therefore necessary to make a number of assumptions in order to proceed. Nevertheless, the picture which has emerged is quite appealing: all spacetime coupling constants become dynamical variables when the effects of baby universes are taken into account. This fact might even solve the puzzle of the cosmological constant. The subject therefore seems worth further investigation
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3. Control and manipulation of antiferromagnetic skyrmions in racetrack
Science.gov (United States)
Xia, Haiyan; Jin, Chendong; Song, Chengkun; Wang, Jinshuai; Wang, Jianbo; Liu, Qingfang
2017-12-01
Controllable manipulations of magnetic skyrmions are essential for next-generation spintronic devices. Here, the duplication and merging of skyrmions, as well as logical AND and OR functions, are designed in antiferromagnetic (AFM) materials with a cusp or smooth Y-junction structures. The operational time are in the dozens of picoseconds, enabling ultrafast information processing. A key factor for the successful operation is the relatively complex Y-junction structures, where domain walls propagate through in a controlled manner, without significant risks of pinning, vanishing or unwanted depinning of existing domain walls, as well as the nucleation of new domain walls. The motions of a multi-bit, namely the motion of an AFM skyrmion-chain in racetrack, are also investigated. Those micromagnetic simulations may contribute to future AFM skyrmion-based spintronic devices, such as nanotrack memory, logic gates and other information processes.
4. Performance of synthetic antiferromagnetic racetrack memory: domain wall versus skyrmion
International Nuclear Information System (INIS)
Tomasello, R; Puliafito, V; Martinez, E; Manchon, A; Ricci, M; Carpentieri, M; Finocchio, G
2017-01-01
A storage scheme based on racetrack memory, where the information can be coded in a domain or a skyrmion, seems to be an alternative to conventional hard disk drive for high density storage. Here, we perform a full micromagnetic study of the performance of synthetic antiferromagnetic (SAF) racetrack memory in terms of velocity and sensitivity to defects by using experimental parameters. We find that, to stabilize a SAF skyrmion, the Dzyaloshinskii–Moriya interaction in the top and the bottom ferromagnet should have an opposite sign. The velocity of SAF skyrmions and SAF Néel domain walls are of the same order and can reach values larger than 1200 m s −1 if a spin–orbit torque from the spin-Hall effect with opposite sign is applied to both ferromagnets. The presence of disordered anisotropy in the form of randomly distributed grains introduces a threshold current for both SAF skyrmions and SAF domain walls motions. (paper)
5. Performance of synthetic antiferromagnetic racetrack memory: domain wall versus skyrmion
KAUST Repository
Tomasello, R
2017-06-20
A storage scheme based on racetrack memory, where the information can be coded in a domain or a skyrmion, seems to be an alternative to conventional hard disk drive for high density storage. Here, we perform a full micromagnetic study of the performance of synthetic antiferromagnetic (SAF) racetrack memory in terms of velocity and sensitivity to defects by using experimental parameters. We find that, to stabilize a SAF skyrmion, the Dzyaloshinskii–Moriya interaction in the top and the bottom ferromagnet should have an opposite sign. The velocity of SAF skyrmions and SAF Néel domain walls are of the same order and can reach values larger than 1200 m s−1 if a spin–orbit torque from the spin-Hall effect with opposite sign is applied to both ferromagnets. The presence of disordered anisotropy in the form of randomly distributed grains introduces a threshold current for both SAF skyrmions and SAF domain walls motions.
6. Performance of synthetic antiferromagnetic racetrack memory: domain wall versus skyrmion
KAUST Repository
Tomasello, R; Puliafito, V; Martinez, E; Manchon, Aurelien; Ricci, M; Carpentieri, M; Finocchio, G
2017-01-01
A storage scheme based on racetrack memory, where the information can be coded in a domain or a skyrmion, seems to be an alternative to conventional hard disk drive for high density storage. Here, we perform a full micromagnetic study
7. Degeneracies and fluctuations of Neel skyrmions in confined geometries
NARCIS (Netherlands)
Keesman, Rick; Leonov, A. O.; van Dieten, P.; Buhrandt, Stefan; Barkema, G. T.; Fritz, Lars; Duine, R. A.
2015-01-01
The recent discovery of tunable Dzyaloshinskii-Moriya interactions in layered magnetic materials with perpendicular magnetic anisotropy makes them promising candidates for stabilization and manipulation of skyrmions at elevated temperatures. In this article, we use Monte Carlo simulations to
8. B =5 Skyrmion as a two-cluster system
Science.gov (United States)
Gudnason, Sven Bjarke; Halcrow, Chris
2018-06-01
The classical B =5 Skyrmion can be approximated by a two-cluster system in which a B =1 Skyrmion is attached to a core B =4 Skyrmion. We quantize this system, allowing the B =1 to freely orbit the core. The configuration space is 11 dimensional but simplifies significantly after factoring out the overall spin and isospin degrees of freedom. We exactly solve the free quantum problem and then include an interaction potential between the Skyrmions numerically. The resulting energy spectrum is compared to the corresponding nuclei—the helium-5/lithium-5 isodoublet. We find approximate parity doubling not seen in the experimental data. In addition, we fail to obtain the correct ground-state spin. The framework laid out for this two-cluster system can readily be modified for other clusters and in particular for other B =4 n +1 nuclei, of which B =5 is the simplest example.
9. Generalised twisted partition functions
CERN Document Server
Petkova, V B
2001-01-01
We consider the set of partition functions that result from the insertion of twist operators compatible with conformal invariance in a given 2D Conformal Field Theory (CFT). A consistency equation, which gives a classification of twists, is written and solved in particular cases. This generalises old results on twisted torus boundary conditions, gives a physical interpretation of Ocneanu's algebraic construction, and might offer a new route to the study of properties of CFT.
10. Manipulation of magnetic Skyrmions with a Scanning Tunneling Microscope
OpenAIRE
Wieser, R.
2016-01-01
The dynamics of a single magnetic Skyrmion in an atomic spin system under the influence of Scanning Tunneling Microscope is investigated by computer simulations solving the Landau-Lifshitz-Gilbert equation. Two possible scenarios are described: manipulation with aid of a spin-polarized tunneling current and by an electric field created by the scanning tunneling microscope. The dynamics during the creation and annihilation process is studied and the possibility to move single Skyrmions is showed.
11. Topological Hall and Spin Hall Effects in Disordered Skyrmionic Textures
OpenAIRE
N'diaye, P. B.; Akosa, C. A.; Manchon, A.
2016-01-01
We carry out a throughout study of the topological Hall and topological spin Hall effects in disordered skyrmionic systems: the dimensionless (spin) Hall angles are evaluated across the energy band structure in the multiprobe Landauer-B\\"uttiker formalism and their link to the effective magnetic field emerging from the real space topology of the spin texture is highlighted. We discuss these results for an optimal skyrmion size and for various sizes of the sample and found that the adiabatic a...
12. Twisted network programming essentials
CERN Document Server
Fettig, Abe
2005-01-01
Twisted Network Programming Essentials from O'Reilly is a task-oriented look at this new open source, Python-based technology. The book begins with recommendations for various plug-ins and add-ons to enhance the basic package as installed. It then details Twisted's collection simple network protocols, and helper utilities. The book also includes projects that let you try out the Twisted framework for yourself. For example, you'll find examples of using Twisted to build web services applications using the REST architecture, using XML-RPC, and using SOAP. Written for developers who want to s
13. Tunable surface configuration of skyrmion lattices in cubic helimagnets
Science.gov (United States)
Wan, Xuejin; Hu, Yangfan; Wang, Biao
2018-06-01
In bulk helimagnets, the presence of magnetic skyrmion lattices is always accompanied by a periodic stress field due to the intrinsic magnetoelastic coupling. The release of this nontrivial stress field at the surface causes a periodic displacement field, which characterizes a novel particle-like property of skyrmion: its surface configuration. Here, we derive the analytical solution of this displacement field for semi-infinite cubic helimagnet with the skyrmion magnetization approximated by the triple-Q representation. For MnSi, we show that the skyrmion lattices have a bumpy surface configuration characterized by periodically arranged peaks with a characteristic height of about 10‑13 m. The pattern of the peaks can be controlled by varying the strength of the applied magnetic field. Moreover, we prove that the surface configuration varies together with the motion and deformation of the skyrmion lattices. As a result, the surface configuration can be tuned by application of electric current, mechanical loads, as well as any other effective external fields for skyrmion lattices.
14. Comparing the dynamics of skyrmions and superconducting vortices
International Nuclear Information System (INIS)
Olson Reichhardt, C.J.; Lin, S.Z.; Ray, D.; Reichhardt, C.
2014-01-01
Highlights: • We describe similarities and differences between skyrmion and vortex dynamics. • The Magnus force can dramatically alter skyrmion transport. • The pinning becomes very weak when the Magnus force is strong. - Abstract: Vortices in type-II superconductors have attracted enormous attention as ideal systems in which to study nonequilibrium collective phenomena, since the self-ordering of the vortices competes with quenched disorder and thermal effects. Dynamic effects found in vortex systems include depinning, nonequilibrium phase transitions, creep, structural order–disorder transitions, and melting. Understanding vortex dynamics is also important for applications of superconductors which require the vortices either to remain pinned or to move in a controlled fashion. Recently, topological defects called skyrmions have been realized experimentally in chiral magnets. Here we highlight similarities and differences between skyrmion dynamics and vortex dynamics. Many of the previous ideas and experimental setups that have been applied to superconducting vortices can also be used to study skyrmions. We also discuss some of the differences between the two systems, such as the potentially large contribution of the Magnus force in the skyrmion system that can dramatically alter the dynamics and transport properties
15. Controllable transport of a skyrmion in a ferromagnetic narrow channel with voltage-controlled magnetic anisotropy
Science.gov (United States)
Wang, Junlin; Xia, Jing; Zhang, Xichao; Zhao, G. P.; Ye, Lei; Wu, Jing; Xu, Yongbing; Zhao, Weisheng; Zou, Zhigang; Zhou, Yan
2018-05-01
Magnetic skyrmions have potential applications in next-generation spintronic devices with ultralow energy consumption. In this work, the current-driven skyrmion motion in a narrow ferromagnetic nanotrack with voltage-controlled magnetic anisotropy (VCMA) is studied numerically. By utilizing the VCMA effect, the transport of skyrmion can be unidirectional in the nanotrack, leading to a one-way information channel. The trajectory of the skyrmion can also be modulated by periodically located VCMA gates, which protects the skyrmion from destruction by touching the track edge. In addition, the location of the skyrmion can be controlled by adjusting the driving pulse length in the presence of the VCMA effect. Our results provide guidelines for practical realization of the skyrmion-based information channel, diode, and skyrmion-based electronic devices such as racetrack memory.
16. Direct writing of room temperature and zero field skyrmion lattices by a scanning local magnetic field
KAUST Repository
Zhang, Senfu; Zhang, Junwei; Zhang, Qiang; Barton, Craig; Neu, Volker; Zhao, Yuelei; Hou, Zhipeng; Wen, Yan; Gong, Chen; Kazakova, Olga; Wang, Wenhong; Peng, Yong; Garanin, Dmitry A.; Chudnovsky, Eugene M.; Zhang, Xixiang
2018-01-01
Magnetic skyrmions are topologically protected nanoscale spin textures exhibiting fascinating physical behaviors. Recent observations of room temperature skyrmions in sputtered multilayer films are an important step towards their use in ultra-low power devices. Such practical applications prefer skyrmions to be stable at zero magnetic fields and room temperature. Here, we report the creation of skyrmion lattices in Pt/Co/Ta multilayers by a scanning local field using magnetic force microscopy tips. We also show that those newly created skyrmion lattices are stable at both room temperature and zero fields. Lorentz transmission electron microscopy measurements reveal that the skyrmions in our films are of Néel-type. To gain a deeper understanding of the mechanism behind the creation of a skyrmion lattice by the scanning of local fields, we perform micromagnetic simulations and find the experimental results to be in agreement with our simulation data. This study opens another avenue for the creation of skyrmion lattices in thin films.
17. Direct writing of room temperature and zero field skyrmion lattices by a scanning local magnetic field
Science.gov (United States)
Zhang, Senfu; Zhang, Junwei; Zhang, Qiang; Barton, Craig; Neu, Volker; Zhao, Yuelei; Hou, Zhipeng; Wen, Yan; Gong, Chen; Kazakova, Olga; Wang, Wenhong; Peng, Yong; Garanin, Dmitry A.; Chudnovsky, Eugene M.; Zhang, Xixiang
2018-03-01
Magnetic skyrmions are topologically protected nanoscale spin textures exhibiting fascinating physical behaviors. Recent observations of room temperature skyrmions in sputtered multilayer films are an important step towards their use in ultra-low power devices. Such practical applications prefer skyrmions to be stable at zero magnetic fields and room temperature. Here, we report the creation of skyrmion lattices in Pt/Co/Ta multilayers by a scanning local field using magnetic force microscopy tips. We also show that those newly created skyrmion lattices are stable at both room temperature and zero fields. Lorentz transmission electron microscopy measurements reveal that the skyrmions in our films are of Néel-type. To gain a deeper understanding of the mechanism behind the creation of a skyrmion lattice by the scanning of local fields, we perform micromagnetic simulations and find the experimental results to be in agreement with our simulation data. This study opens another avenue for the creation of skyrmion lattices in thin films.
18. Stability of skyrmions on curved surfaces in the presence of a magnetic field
Energy Technology Data Exchange (ETDEWEB)
Carvalho-Santos, V.L., E-mail: vagson.carvalho@usach.cl [Instituto Federal de Educação, Ciência e Tecnologia Baiano - Campus Senhor do Bonfim, Km 04 Estrada da Igara, 48970-000 Senhor do Bonfim, Bahia (Brazil); Departamento de Física, Universidad de Santiago de Chile and CEDENNA, Avda. Ecuador 3493, Santiago (Chile); Elias, R.G.; Altbir, D. [Departamento de Física, Universidad de Santiago de Chile and CEDENNA, Avda. Ecuador 3493, Santiago (Chile); Fonseca, J.M. [Universidade Federal de Viçosa, Departamento de Física, Avenida Peter Henry Rolfs s/n, 36570-000 Viçosa, MG (Brazil)
2015-10-01
We study the stability and energetics associated to skyrmions appearing as excitations on curved surfaces. Using a continuum model we show that the presence of cylindrically radial and azimuthal fields destabilize the skyrmions that appear in the absence of an external field. Weak fields generate fractional skyrmions while strong magnetic fields yield stable 2π-skyrmions, which have their widths diminished by the magnetic field strength. Under azimuthal fields vortex appears as stable state on the curved surface. - Highlights: • Stability of skyrmions on curved surfaces in the presence of a magnetic field. • Weak fields can destabilize skyrmions. • Strong magnetic fields yield the appearing of 2π-skyrmions. • The width of skyrmions is determined by the curvature and magnetic field strength. • Under azimuthal fields vortex appears as stable states.
19. Direct writing of room temperature and zero field skyrmion lattices by a scanning local magnetic field
KAUST Repository
Zhang, Senfu
2018-03-29
Magnetic skyrmions are topologically protected nanoscale spin textures exhibiting fascinating physical behaviors. Recent observations of room temperature skyrmions in sputtered multilayer films are an important step towards their use in ultra-low power devices. Such practical applications prefer skyrmions to be stable at zero magnetic fields and room temperature. Here, we report the creation of skyrmion lattices in Pt/Co/Ta multilayers by a scanning local field using magnetic force microscopy tips. We also show that those newly created skyrmion lattices are stable at both room temperature and zero fields. Lorentz transmission electron microscopy measurements reveal that the skyrmions in our films are of Néel-type. To gain a deeper understanding of the mechanism behind the creation of a skyrmion lattice by the scanning of local fields, we perform micromagnetic simulations and find the experimental results to be in agreement with our simulation data. This study opens another avenue for the creation of skyrmion lattices in thin films.
20. Skyrmion burst and multiple quantum walk in thin ferromagnetic films
International Nuclear Information System (INIS)
Ezawa, Motohiko
2011-01-01
We propose a new type of quantum walk in thin ferromagnetic films. A giant Skyrmion collapses to a singular point in a thin ferromagnetic film, emitting spin waves, when external magnetic field is increased beyond the critical one. After the collapse the remnant is a quantum walker carrying spin S. We determine its time evolution and show the diffusion process is a continuous-time quantum walk. We also analyze an interference of two quantum walkers after two Skyrmion bursts. The system presents a new type of quantum walk for S>1/2, where a quantum walker breaks into 2S quantum walkers. -- Highlights: → A giant Skyrmion collapses to a singular point by applying strong magnetic field. → Quantum walk is realized in thin ferromagnetic films by Skyrmion collapsing. → Quantum walks for S=1/2 and 1 are exact solvable, where S represents the spin. → Quantum walks for >1/2 presents a new type of quantum walks, i.e., 'multiple quantum walks'. → Skyrmion bursts which occur simultaneously exhibit an interference as a manifestation of quantum walk.
1. Topological mass of magnetic Skyrmions probed by ultrafast dynamic imaging
International Nuclear Information System (INIS)
Buettner, Felix
2013-01-01
In this thesis, we investigate the GHz dynamics of skyrmionic spin structures by means of pump-probe dynamic imaging to determine the equation of motion that governs the behavior of these technologically relevant spin structures. To achieve this goal, we first designed and optimized a perpendicular magnetic anisotropy CoB/Pt multilayer material for low magnetic pinning, as required for ultrafast pump-probe imaging experiments. Second, we developed an integrated sample design for X-ray holography capable of tracking relative magnetic positional changes down to 3 nm spatial resolution. These advances enabled us to image the trajectory of a single magnetic Skyrmion. We find that the motion is comprised of two gyrotropic modes, one clockwise and one counterclockwise. The existence of two modes shows that Skyrmions are massive quasiparticles. From their derived frequencies we find an inertial mass for the Skyrmion which is a factor of five larger than expected based on existing models for inertia in magnetism. Our results demonstrate that the mass of Skyrmions is based on a novel mechanism emerging from their confined nature, which is a direct consequence of their topology.
2. The influence of the edge effect on the skyrmion generation in a magnetic nanotrack
Directory of Open Access Journals (Sweden)
N. Ran
2017-02-01
Full Text Available Magnetic skyrmions might be used for building next-generation nanomagnetic and spintronic devices, as they have several perspective properties, such as topologically protected stability, nanoscale size, and ultra-low depinning current density. Here we study the influence of the edge effect on the current-induced generation of a magnetic skyrmion in a finite-length thin-film ferromagnetic nanotrack with interface-induced Dzyaloshinskii-Moriya interaction. It shows that a stable skyrmion or a bunch of skyrmions can be successfully generated as long as the distance between the current injection region and the nanotrack terminal is larger than a certain threshold. We investigate the failed skyrmion generation caused by the edge effect, which will lead to an error writing event. We also present the phase diagrams of the skyrmion generation obtained for different material and geometric parameters. Our results could be useful for designing skyrmion-based information storage devices.
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5. Baby supplies you need
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Newborn care - baby supplies ... wintertime. Mobile. This can entertain and distract a baby who is fussy or is having a hard ... rainfall). These sounds can be soothing for the baby and can help him sleep.
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11. Twisted classical Poincare algebras
International Nuclear Information System (INIS)
Lukierski, J.; Ruegg, H.; Tolstoy, V.N.; Nowicki, A.
1993-11-01
We consider the twisting of Hopf structure for classical enveloping algebra U(g), where g is the inhomogeneous rotations algebra, with explicite formulae given for D=4 Poincare algebra (g=P 4 ). The comultiplications of twisted U F (P 4 ) are obtained by conjugating primitive classical coproducts by F element of U(c)xU(c), where c denotes any Abelian subalgebra of P 4 , and the universal R-matrices for U F (P 4 ) are triangular. As an example we show that the quantum deformation of Poincare algebra recently proposed by Chaichian and Demiczev is a twisted classical Poincare algebra. The interpretation of twisted Poincare algebra as describing relativistic symmetries with clustered 2-particle states is proposed. (orig.)
12. WORKSHOP: Let's twist again..
Energy Technology Data Exchange (ETDEWEB)
Villalobos Baillie, Orlando
1988-12-15
In the quantum chromodynamics (QCD) candidate theory of interquark forces, calculations involve summing the effects from many different possible quark/gluon interactions. In addition to the 'leading term' frequently used as the basis for QCD calculations, additional contributions — so-called 'higher twists' — are modulated by powers of kinematical factors. An illuminating international workshop to discuss higher twist QCD was held at the College de France, Paris, from 21-23 September.
13. The skyrmion-bubble transition in a ferromagnetic thin film
Directory of Open Access Journals (Sweden)
Anne Bernand-Mantel, Lorenzo Camosi, Alexis Wartelle, Nicolas Rougemaille, Michaël Darques, Laurent Ranno
2018-05-01
Full Text Available Magnetic skyrmions and bubbles, observed in ferromagnetic thin films with perpendicular magnetic anisotropy, are topological solitons which differ by their characteristic size and the balance in the energies at the origin of their stabilisation. However, these two spin textures have the same topology and a continuous transformation between them is allowed. In the present work, we derive an analytical model to explore the skyrmion-bubble transition. We evidence a region in the parameter space where both topological soliton solutions coexist and close to which transformations between skyrmion and bubbles are observed as a function of the magnetic field. Above a critical point, at which the energy barrier separating both solutions vanishes, only one topological soliton solution remains, which size can be continuously tuned from micrometer to nanometer with applied magnetic field.
14. Topological Hall and spin Hall effects in disordered skyrmionic textures
KAUST Repository
Ndiaye, Papa Birame; Akosa, Collins Ashu; Manchon, Aurelien
2017-01-01
We carry out a thorough study of the topological Hall and topological spin Hall effects in disordered skyrmionic systems: the dimensionless (spin) Hall angles are evaluated across the energy-band structure in the multiprobe Landauer-Büttiker formalism and their link to the effective magnetic field emerging from the real-space topology of the spin texture is highlighted. We discuss these results for an optimal skyrmion size and for various sizes of the sample and find that the adiabatic approximation still holds for large skyrmions as well as for nanoskyrmions. Finally, we test the robustness of the topological signals against disorder strength and show that the topological Hall effect is highly sensitive to momentum scattering.
15. Topological Hall and spin Hall effects in disordered skyrmionic textures
KAUST Repository
Ndiaye, Papa Birame
2017-02-24
We carry out a thorough study of the topological Hall and topological spin Hall effects in disordered skyrmionic systems: the dimensionless (spin) Hall angles are evaluated across the energy-band structure in the multiprobe Landauer-Büttiker formalism and their link to the effective magnetic field emerging from the real-space topology of the spin texture is highlighted. We discuss these results for an optimal skyrmion size and for various sizes of the sample and find that the adiabatic approximation still holds for large skyrmions as well as for nanoskyrmions. Finally, we test the robustness of the topological signals against disorder strength and show that the topological Hall effect is highly sensitive to momentum scattering.
16. Intrinsic nonadiabatic topological torque in magnetic skyrmions and vortices
KAUST Repository
Akosa, Collins Ashu; Ndiaye, Papa Birame; Manchon, Aurelien
2017-01-01
We propose that topological spin currents flowing in topologically nontrivial magnetic textures, such as magnetic skyrmions and vortices, produce an intrinsic nonadiabatic torque of the form Tt∼[(∂xm×∂ym)·m]∂ym. We show that this torque, which is absent in one-dimensional domain walls and/or nontopological textures, is responsible for the enhanced nonadiabaticity parameter observed in magnetic vortices compared to one-dimensional textures. The impact of this torque on the motion of magnetic skyrmions is expected to be crucial, especially to determine their robustness against defects and pinning centers.
17. Skyrmionic spin Seebeck effect via dissipative thermomagnonic torques
Science.gov (United States)
Kovalev, Alexey A.
2014-06-01
We derive thermomagnonic torque and its "β-type" dissipative correction from the stochastic Landau-Lifshitz-Gilbert equation. The β-type dissipative correction describes viscous coupling between magnetic dynamics and magnonic current and it stems from spin mistracking of the magnetic order. We show that thermomagnonic torque is important for describing temperature gradient induced motion of skyrmions in helical magnets while dissipative correction plays an essential role in generating transverse Magnus force. We propose to detect such skyrmionic motion by employing the transverse spin Seebeck effect geometry.
18. Intrinsic nonadiabatic topological torque in magnetic skyrmions and vortices
KAUST Repository
Akosa, Collins Ashu
2017-03-01
We propose that topological spin currents flowing in topologically nontrivial magnetic textures, such as magnetic skyrmions and vortices, produce an intrinsic nonadiabatic torque of the form Tt∼[(∂xm×∂ym)·m]∂ym. We show that this torque, which is absent in one-dimensional domain walls and/or nontopological textures, is responsible for the enhanced nonadiabaticity parameter observed in magnetic vortices compared to one-dimensional textures. The impact of this torque on the motion of magnetic skyrmions is expected to be crucial, especially to determine their robustness against defects and pinning centers.
19. Skyrmions and vector mesons: a symmetric approach
International Nuclear Information System (INIS)
Caldi, D.G.
1984-01-01
We propose an extension of the effective, low-energy chiral Lagrangian known as the Skyrme model, to one formulated by a non-linear sigma model generalized to include vector mesons in a symmetric way. The model is based on chiral SU(6) x SU(6) symmetry spontaneously broken to static SU(6). The rho and other vector mesons are dormant Goldstone bosons since they are in the same SU(6) multiplet as the pion and other pseudoscalars. Hence the manifold of our generalized non-linear sigma model is the coset space (SU(6) x SU(6))/Su(6). Relativistic effects, via a spin-dependent mass term, break the static SU(6) and give the vectors a mass. The model can then be fully relativistic and covariant. The lowest-lying Skyrmion in this model is the whole baryonic 56-plet, which splits into the octet and decuplet in the presence of relativistic SU(6)-breaking. Due to the built-in SU(6) and the presence of vector mesons, the model is expected to have better phenomenological results, as well as providing a conceptually more unified picture of mesons and baryons. 29 references
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1. Interactive baby feeding bottle
NARCIS (Netherlands)
2013-01-01
An interactive baby bottle with an electronic unit is disclosed. The electronic unit comprises a sensor unit configured to sense the heart beat of a person bottle feeding a baby and an actuator unit configured to transmit the sensed heart beat to the baby. The disclosed interactive baby bottle can
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Full Text Available ... In This Topic Breastfeeding help Breastfeeding is best Food allergies and baby Formula feeding How to breastfeed Keeping a breastfeeding log Keeping breast milk safe and healthy Problems and discomforts when breastfeeding Starting your baby on solid foods Using a breast pump Baby Feeding your baby ...
3. Magnus force on quantum Hall skyrmions and vortices
International Nuclear Information System (INIS)
Dhar, S.; Basu, B.; Bandyopadhyay, P.
2003-01-01
We have discussed here the Magnus force acting on the vortices and skyrmions in the quantum Hall systems. We have found that it is generated by the chirality of the system which is associated with the Berry phase and is same for both the cases
4. Skyrmion dynamics in single-hole Neel ordered doped two-dimensional antiferromagnets with arbitrary spin
International Nuclear Information System (INIS)
Moura, A.R.; Pereira, A.R.; Moura-Melo, W.A.; Pires, A.S.T.
2008-01-01
We develop an effective theory to study the skyrmion dynamics in the presence of a hole (removed spins from the lattice) in Neel ordered two-dimensional antiferromagnets with arbitrary spin value S. The general equation of motion for the 'mass center' of this structure is obtained. The frequency of small amplitude oscillations of pinned skyrmions around the defect center is calculated. It is proportional to the hole size and inversely proportional to the square of the skyrmion size
5. A Transformation Called "Twist"
Science.gov (United States)
Hwang, Daniel
2010-01-01
The transformations found in secondary mathematics curriculum are typically limited to stretches and translations (e.g., ACARA, 2010). Advanced students may find the transformation, twist, to be of further interest. As most available resources are written for professional-level readers, this article is intended to be an introduction accessible to…
6. SpaceTwist
DEFF Research Database (Denmark)
Yiu, Man Lung; Jensen, Christian Søndergaard; Xuegang, Huang
2008-01-01
-based matching generally fall short in offering practical query accuracy guarantees. Our proposed framework, called SpaceTwist, rectifies these shortcomings for k nearest neighbor (kNN) queries. Starting with a location different from the user's actual location, nearest neighbors are retrieved incrementally...
7. Twisting the Mirror TBA
NARCIS (Netherlands)
Arutyunov, G.E.; de Leeuw, M.; van Tongeren, S.J.
2010-01-01
We study finite-size corrections to the magnon dispersion relation in three models which differ from string theory on AdS5 x S5 in their boundary conditions. Asymptotically, this is accomplished by twisting the transfer matrix in a way which manifestly preserves integrability. In model I all
8. Safe Sleep for Babies
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... 5 MB] Read the MMWR Science Clips Safe Sleep for Babies Eliminating hazards Recommend on Facebook Tweet ... Page Problem Every year, there are thousands of sleep-related deaths among babies. View large image and ...
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10. Baby Brain Map
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... a Member Home Resources & Services Professional Resource Baby Brain Map Mar 17, 2016 The Brain Map was adapted in 2006 by ZERO TO ... supports Adobe Flash Player. To view the Baby Brain Map, please visit this page on a browser ...
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Full Text Available ... a valid e-mail address. Your information: Your recipient's information: Your personal message: Thank you! Your e- ... good for babies. You and your baby may need time and practice to get comfortable breastfeeding, but ...
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Full Text Available ... and your partner to bond with her. Breast milk is the best food for your baby during ... life. Learn how to breastfeed and why breast milk is so good for babies. You and your ...
15. Shaken baby symptoms (image)
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... is a severe form of head injury caused by the baby's brain rebounding inside of the baby's skull when shaken. In this injury there is bruising of the brain, swelling, pressure, and bleeding (intracerebral hemorrhage). This can easily lead ...
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... Development Infections Diseases & Conditions Pregnancy & Baby Nutrition & Fitness Emotions & Behavior School & Family Life First Aid & Safety Doctors & ... for sensitive skin.) Unless your baby has allergies , eczema/atopic dermatitis , or another condition causing sensitive skin, ...
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19. Your Baby's Growth: 12 Months
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... Safe Videos for Educators Search English Español Your Baby's Growth: 12 Months KidsHealth / For Parents / Your Baby's ... doubled his or her birth weight. Is My Baby Growing Normally? Babies' growth begins to slow as ...
20. Your Baby's Growth: 5 Months
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... Safe Videos for Educators Search English Español Your Baby's Growth: 5 Months KidsHealth / For Parents / Your Baby's ... a cause for concern. How Much Will My Baby Grow? By 5 months, your baby's birth weight ...
1. Immunizations for Preterm Babies
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... Issues Health Issues Health Issues Conditions Injuries & Emergencies Vaccine Preventable Diseases ... Children > Safety & Prevention > Immunizations > Immunizations For Preterm Babies Safety & ...
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3. The New Baby.
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Brain, Helen
This book for beginning readers tells the story of a South African priest and his wife who are ashamed when their daughter tells them she is going to have a baby. They refuse to have anything to do with her when she is pregnant. However, when the baby comes, everything changes and they come to accept and love the baby. Large black and white…
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6. Twisted quantum doubles
Directory of Open Access Journals (Sweden)
Daijiro Fukuda
2004-01-01
Full Text Available Using diagrammatic pictures of tensor contractions, we consider a Hopf algebra (Aop⊗ℛλA** twisted by an element ℛλ∈A*⊗Aop corresponding to a Hopf algebra morphism λ:A→A. We show that this Hopf algebra is quasitriangular with the universal R-matrix coming from ℛλ when λ2=idA, generalizing the quantum double construction which corresponds to the case λ=idA.
7. A point particle model of lightly bound skyrmions
Directory of Open Access Journals (Sweden)
Mike Gillard
2017-04-01
Full Text Available A simple model of the dynamics of lightly bound skyrmions is developed in which skyrmions are replaced by point particles, each carrying an internal orientation. The model accounts well for the static energy minimizers of baryon number 1≤B≤8 obtained by numerical simulation of the full field theory. For 9≤B≤23, a large number of static solutions of the point particle model are found, all closely resembling size B subsets of a face centred cubic lattice, with the particle orientations dictated by a simple colouring rule. Rigid body quantization of these solutions is performed, and the spin and isospin of the corresponding ground states extracted. As part of the quantization scheme, an algorithm to compute the symmetry group of an oriented point cloud, and to determine its corresponding Finkelstein–Rubinstein constraints, is devised.
8. Skyrmion clusters from Bloch lines in ferromagnetic films
KAUST Repository
Garanin, Dmitry A.
2017-12-29
Conditions under which various skyrmion objects emerge in experiments on thin magnetic films remain largely unexplained. We investigate numerically centrosymmetric spin lattices in films of finite thickness with ferromagnetic exchange, magnetic anisotropy, and dipole-dipole interaction. Evolution of labyrinth domains into compact topological structures on application of the magnetic field is found to be governed by the configuration of Bloch lines inside domain walls. Depending on the combination of Bloch lines, the magnetic domains evolve into individual skyrmions, biskyrmions, or more complex topological objects. While the geometry of such objects is sensitive to the parameters, their topological charge is uniquely determined by the topological charge of Bloch lines inside the magnetic domain from which the object emerges.
9. Multi-skyrmion solutions of a sixth order Skyrme model
International Nuclear Information System (INIS)
Floratos, I.
2001-08-01
In this thesis, we study some of the classical properties of an extension of the Skyrme model defined by adding a sixth order derivative term to the Lagrangian. In chapter 1, we review the physical as well as the mathematical motivation behind the study of the Skyrme model and in chapter 2, we give a brief summary of various extended Skyrme models that have been proposed over the last few years. We then define a new sixth order Skyrme model by introducing a dimensionless parameter λ that denotes the mixing between the two higher order terms, the Skyrme term and the sixth order term. In chapter 3 we compute numerically the multi-skyrmion solutions of this extended model and show that they have the same symmetries with the usual skyrmion solutions. In addition, we analyse the dependence of the energy and radius of these classical solutions with respect to the coupling constant λ. We compare our results with experimental data and determine whether this modified model can provide us with better theoretical predictions than the original one. In chapter 4, we use the rational map ansatz, introduced by Houghton, Manton and Sutcliffe, to approximate minimum energy multi-skyrmion solutions with B ≤ 9 of the SU(2) model and with B ≤ 6 of the SU(3) model. We compare our results with the ones obtained numerically and show that the rational map ansatz works just as well for the generalised model as for the pure Skyrme model, at least for B ≤ 5. In chapter 5, we use a generalisation of the rational map ansatz, introduced by loannidou, Piette and Zakrzewski, to construct analytically some topologically non-trivial solutions of the extended model in SU(3). These solutions are spherically symmetric and some of them can be interpreted as bound states of skyrmions. Finally, we use the same ansatz to construct low energy configurations of the SU(N) sixth order Skyrme model. (author)
10. Skyrmion based universal memory operated by electric current
Energy Technology Data Exchange (ETDEWEB)
Zang, Jiadong; Chien, Chia-Ling; Li, Yufan; Lake, Roger K.; Yin, Gen
2017-09-26
A method for generating a skyrmion, comprising: depositing a vertical metallic nanopillar electrode on a first side of a helimagnetic thin film, the helimagnetic thin film having a contact on a second side to provide a current drain; injecting a current through the vertical metallic nanopillar electrode to generate a rotating field; and applying a static upward magnetic field perpendicular to the helimagnetic thin film to maintain an FM phase background.
11. Real-space Berry phases: Skyrmion soccer (invited)
Science.gov (United States)
Everschor-Sitte, Karin; Sitte, Matthias
2014-05-01
Berry phases occur when a system adiabatically evolves along a closed curve in parameter space. This tutorial-like article focuses on Berry phases accumulated in real space. In particular, we consider the situation where an electron traverses a smooth magnetic structure, while its magnetic moment adjusts to the local magnetization direction. Mapping the adiabatic physics to an effective problem in terms of emergent fields reveals that certain magnetic textures, skyrmions, are tailormade to study these Berry phase effects.
12. Real-space Berry phases: Skyrmion soccer (invited)
Energy Technology Data Exchange (ETDEWEB)
Everschor-Sitte, Karin, E-mail: karin@physics.utexas.edu; Sitte, Matthias [The University of Texas at Austin, Department of Physics, 2515 Speedway, Austin, Texas 78712 (United States)
2014-05-07
Berry phases occur when a system adiabatically evolves along a closed curve in parameter space. This tutorial-like article focuses on Berry phases accumulated in real space. In particular, we consider the situation where an electron traverses a smooth magnetic structure, while its magnetic moment adjusts to the local magnetization direction. Mapping the adiabatic physics to an effective problem in terms of emergent fields reveals that certain magnetic textures, skyrmions, are tailormade to study these Berry phase effects.
13. Real-space Berry phases: Skyrmion soccer (invited)
International Nuclear Information System (INIS)
Everschor-Sitte, Karin; Sitte, Matthias
2014-01-01
Berry phases occur when a system adiabatically evolves along a closed curve in parameter space. This tutorial-like article focuses on Berry phases accumulated in real space. In particular, we consider the situation where an electron traverses a smooth magnetic structure, while its magnetic moment adjusts to the local magnetization direction. Mapping the adiabatic physics to an effective problem in terms of emergent fields reveals that certain magnetic textures, skyrmions, are tailormade to study these Berry phase effects
14. Hybridizing the Skyrmion with an Anti-de-Sitter bag
International Nuclear Information System (INIS)
Rosu, H.
1992-02-01
We discuss a phenomenological model of the nucleon in which a small Anti-de-Sitter bag is placed into the Skyrmion configuration. Such a bag has a timelike boundary and allows naturally the Cheshire Cat Principle. Very important in this model is the membrane of the bag, the 3-dimensional manifold S 1 xS 2 , in which topological techniques will come into play. (author). 63 refs
15. Pinning mode of integer quantum Hall Wigner crystal of skyrmions
Science.gov (United States)
Zhu, Han; Sambandamurthy, G.; Chen, Y. P.; Jiang, P.-H.; Engel, L. W.; Tsui, D. C.; Pfeiffer, L. N.; West, K. W.
2009-03-01
Just away from integer Landau level (LL) filling factors ν, the dilute quasi-particles/holes at the partially filled LL form an integer-quantum-Hall Wigner crystal, which exhibits microwave pinning mode resonances [1]. Due to electron-electron interaction, it was predicted that the elementary excitation around ν= 1 is not a single spin flip, but a larger-scale spin texture, known as a skyrmion [2]. We have compared the pinning mode resonances [1] of integer quantum Hall Wigner crystals formed in the partly filled LL just away from ν= 1 and ν= 2, in the presence of an in-plane magnetic field. As an in-plane field is applied, the peak frequencies of the resonances near ν= 1 increase, while the peak frequencies below ν= 2 show neligible dependence on in-plane field. We interpret this observation as due to a skyrmion crystal phase around ν= 1 and a single-hole Wigner crystal phase below ν= 2. The in-plane field increases the Zeeman gap and causes shrinking of the skyrmion size toward single spin flips. [1] Yong P. Chen et al., Phys. Rev. Lett. 91, 016801 (2003). [2] S. L. Sondhi et al., Phys. Rev. B 47, 16 419 (1993); L. Brey et al., Phys. Rev. Lett. 75, 2562 (1995).
16. Micromagnetic study of skyrmion stability in confined magnetic structures with perpendicular anisotropy
Science.gov (United States)
Novak, R. L.; Garcia, F.; Novais, E. R. P.; Sinnecker, J. P.; Guimarães, A. P.
2018-04-01
Skyrmions are emerging topological spin structures that are potentially revolutionary for future data storage and spintronics applications. The existence and stability of skyrmions in magnetic materials is usually associated to the presence of the Dzyaloshinskii-Moriya interaction (DMI) in bulk magnets or in magnetic thin films lacking inversion symmetry. While some methods have already been proposed to generate isolated skyrmions in thin films with DMI, a thorough study of the conditions under which the skyrmions will remain stable in order to be manipulated in an integrated spintronic device are still an open problem. The stability of such structures is believed to be a result of ideal combinations of perpendicular magnetic anisotropy (PMA), DMI and the interplay between geometry and magnetostatics. In the present work we show some micromagnetic results supporting previous experimental observations of magnetic skyrmions in spin-valve stacks with a wide range of DMI values. Using micromagnetic simulations of cobalt-based disks, we obtain the magnetic ground state configuration for several values of PMA, DMI and geometric parameters. Skyrmion numbers, corresponding to the topological charge, are calculated in all cases and confirm the occurrence of isolated, stable, axially symmetric skyrmions for several combinations of DMI and anisotropy constant. The stability of the skyrmions in disks is then investigated under magnetic field and spin-polarized current, in finite temperature, highlighting the limits of applicability of these spin textures in spintronic devices.
17. Origin of temperature and field dependence of magnetic skyrmion size in ultrathin nanodots
Science.gov (United States)
Tomasello, R.; Guslienko, K. Y.; Ricci, M.; Giordano, A.; Barker, J.; Carpentieri, M.; Chubykalo-Fesenko, O.; Finocchio, G.
2018-02-01
Understanding the physical properties of magnetic skyrmions is important for fundamental research with the aim to develop new spintronic device paradigms where both logic and memory can be integrated at the same level. Here, we show a universal model based on the micromagnetic formalism that can be used to study skyrmion stability as a function of magnetic field and temperature. We consider ultrathin, circular ferromagnetic magnetic dots. Our results show that magnetic skyrmions with a small radius—compared to the dot radius—are always metastable, while large radius skyrmions form a stable ground state. The change of energy profile determines the weak (strong) size dependence of the metastable (stable) skyrmion as a function of temperature and/or field.
18. Quantized transport for a skyrmion moving on a two-dimensional periodic substrate
Science.gov (United States)
Reichhardt, C.; Ray, D.; Reichhardt, C. J. Olson
2015-03-01
We examine the dynamics of a skyrmion moving over a two-dimensional periodic substrate utilizing simulations of a particle-based skyrmion model. We specifically examine the role of the nondissipative Magnus term on the driven motion and the resulting skyrmion velocity-force curves. In the overdamped limit, there is a depinning transition into a sliding state in which the skyrmion moves in the same direction as the external drive. When there is a finite Magnus component in the equation of motion, a skyrmion in the absence of a substrate moves at an angle with respect to the direction of the external driving force. When a periodic substrate is added, the direction of motion or Hall angle of the skyrmion is dependent on the amplitude of the external drive, only approaching the substrate-free limit for higher drives. Due to the underlying symmetry of the substrate the direction of skyrmion motion does not change continuously as a function of drive, but rather forms a series of discrete steps corresponding to integer or rational ratios of the velocity components perpendicular ( ) and parallel ( ) to the external drive direction: / =n /m , where n and m are integers. The skyrmion passes through a series of directional locking phases in which the motion is locked to certain symmetry directions of the substrate for fixed intervals of the drive amplitude. Within a given directionally locked phase, the Hall angle remains constant and the skyrmion moves in an orderly fashion through the sample. Signatures of the transitions into and out of these locked phases take the form of pronounced cusps in the skyrmion velocity versus force curves, as well as regions of negative differential mobility in which the net skyrmion velocity decreases with increasing external driving force. The number of steps in the transport curve increases when the relative strength of the Magnus term is increased. We also observe an overshoot phenomena in the directional locking, where the skyrmion motion
19. Organic Baby Food: Better for Baby?
Science.gov (United States)
... al. Organic foods: Health and environmental advantages and disadvantages. Pediatrics. 2012;130:e1406. Morin K. Organic baby ... Policy Notice of Privacy Practices Notice of Nondiscrimination Advertising Mayo Clinic is a not-for-profit organization ...
20. Twisted mass lattice QCD
International Nuclear Information System (INIS)
Shindler, A.
2007-07-01
I review the theoretical foundations, properties as well as the simulation results obtained so far of a variant of the Wilson lattice QCD formulation: Wilson twisted mass lattice QCD. Emphasis is put on the discretization errors and on the effects of these discretization errors on the phase structure for Wilson-like fermions in the chiral limit. The possibility to use in lattice simulations different lattice actions for sea and valence quarks to ease the renormalization patterns of phenomenologically relevant local operators, is also discussed. (orig.)
1. Twisted mass lattice QCD
Energy Technology Data Exchange (ETDEWEB)
Shindler, A. [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany). John von Neumann-Inst. fuer Computing NIC
2007-07-15
I review the theoretical foundations, properties as well as the simulation results obtained so far of a variant of the Wilson lattice QCD formulation: Wilson twisted mass lattice QCD. Emphasis is put on the discretization errors and on the effects of these discretization errors on the phase structure for Wilson-like fermions in the chiral limit. The possibility to use in lattice simulations different lattice actions for sea and valence quarks to ease the renormalization patterns of phenomenologically relevant local operators, is also discussed. (orig.)
2. Twist limits for late twisting double somersaults on trampoline.
Science.gov (United States)
Yeadon, M R; Hiley, M J
2017-06-14
An angle-driven computer simulation model of aerial movement was used to determine the maximum amount of twist that could be produced in the second somersault of a double somersault on trampoline using asymmetrical movements of the arms and hips. Lower bounds were placed on the durations of arm and hip angle changes based on performances of a world trampoline champion whose inertia parameters were used in the simulations. The limiting movements were identified as the largest possible odd number of half twists for forward somersaulting takeoffs and even number of half twists for backward takeoffs. Simulations of these two limiting movements were found using simulated annealing optimisation to produce the required amounts of somersault, tilt and twist at landing after a flight time of 2.0s. Additional optimisations were then run to seek solutions with the arms less adducted during the twisting phase. It was found that 3½ twists could be produced in the second somersault of a forward piked double somersault with arms abducted 8° from full adduction during the twisting phase and that three twists could be produced in the second somersault of a backward straight double somersault with arms fully adducted to the body. These two movements are at the limits of performance for elite trampolinists. Copyright © 2017 Elsevier Ltd. All rights reserved.
3. TEK twisted gradient flow running coupling
CERN Document Server
Pérez, Margarita García; Keegan, Liam; Okawa, Masanori
2014-01-01
We measure the running of the twisted gradient flow coupling in the Twisted Eguchi-Kawai (TEK) model, the SU(N) gauge theory on a single site lattice with twisted boundary conditions in the large N limit.
4. Teaching Spatial Awareness for Better Twisting Somersaults.
Science.gov (United States)
Hennessy, Jeff T.
1985-01-01
The barani (front somersault with one-half twist) and the back somersault with one twist are basic foundation skills necessary for more advanced twisting maneuvers. Descriptions of these movements on a trampoline surface are offered. (DF)
5. Twisting perturbed parafermions
Directory of Open Access Journals (Sweden)
A.V. Belitsky
2017-07-01
Full Text Available The near-collinear expansion of scattering amplitudes in maximally supersymmetric Yang–Mills theory at strong coupling is governed by the dynamics of stings propagating on the five sphere. The pentagon transitions in the operator product expansion which systematize the series get reformulated in terms of matrix elements of branch-point twist operators in the two-dimensional O(6 nonlinear sigma model. The facts that the latter is an asymptotically free field theory and that there exists no local realization of twist fields prevents one from explicit calculation of their scaling dimensions and operator product expansion coefficients. This complication is bypassed making use of the equivalence of the sigma model to the infinite-level limit of WZNW models perturbed by current–current interactions, such that one can use conformal symmetry and conformal perturbation theory for systematic calculations. Presently, to set up the formalism, we consider the O(3 sigma model which is reformulated as perturbed parafermions.
6. Spinning geometry = Twisted geometry
International Nuclear Information System (INIS)
Freidel, Laurent; Ziprick, Jonathan
2014-01-01
It is well known that the SU(2)-gauge invariant phase space of loop gravity can be represented in terms of twisted geometries. These are piecewise-linear-flat geometries obtained by gluing together polyhedra, but the resulting geometries are not continuous across the faces. Here we show that this phase space can also be represented by continuous, piecewise-flat three-geometries called spinning geometries. These are composed of metric-flat three-cells glued together consistently. The geometry of each cell and the manner in which they are glued is compatible with the choice of fluxes and holonomies. We first remark that the fluxes provide each edge with an angular momentum. By studying the piecewise-flat geometries which minimize edge lengths, we show that these angular momenta can be literally interpreted as the spin of the edges: the geometries of all edges are necessarily helices. We also show that the compatibility of the gluing maps with the holonomy data results in the same conclusion. This shows that a spinning geometry represents a way to glue together the three-cells of a twisted geometry to form a continuous geometry which represents a point in the loop gravity phase space. (paper)
7. How to Twist a Knot
DEFF Research Database (Denmark)
Randrup, Thomas; Røgen, Peter
1997-01-01
is an invariant of ambient isotopy measuring the topological twist of the closed strip. We classify closed strips in euclidean 3-space by their knots and their twisting number. We prove that this classification exactly divides closed strips into isotopy classes. Using this classification we point out how some...
8. Pinning of magnetic skyrmions in a monolayer Co film on Pt(111): Theoretical characterization and exemplified utilization
Science.gov (United States)
Stosic, Dusan; Ludermir, Teresa B.; Milošević, Milorad V.
2017-12-01
Magnetic skyrmions are nanoscale windings of the spin structure that can be observed in chiral magnets and hold promise for potential applications in storing or processing information. Pinning due to ever-present material imperfections crucially affects the mobility of skyrmions. Therefore, a proper understanding of how magnetic skyrmions pin to defects is necessary for the development and performance of spintronic devices. Here we present a fundamental analysis on the interactions of single skyrmions with atomic defects of distinctly different origins, in a Co monolayer on Pt, based on minimum-energy paths considerations and atomic-spin simulations. We first report the preferred pinning loci of the skyrmion as a function of its nominal size and the type of defect being considered, to further reveal the manipulation and "breathing" of skyrmion core in the vicinity of a defect. We also show the behavior of skyrmions in the presence of an extended defect of particular geometry, that can lead to ratcheted skyrmion motion or a facilitated guidance on a defect "trail." We close the study with reflections on the expected thermal stability of the skyrmion against collapse on itself for a given nature of the defect, and discuss the applications where control of skyrmions by defects is of particular interest.
9. Statistics of Skyrmions and the ν=5/2 puzzle
International Nuclear Information System (INIS)
Dziarmaga, J.
1997-01-01
For the hard-core interaction there is some freedom left in the choice of the exact multi-Skyrmionic wave function close-quote s topology. The statistics of textured quasiholes, analyzed by calculation of the Berry phase, depends on this choice of topology. We find a class of textured two-hole eigenstates of the Coulomb interaction. There is no definite quantum statistics, but there is a definite rule of how to construct Coulomb eigenstates out of the hard-core wave functions. A wave function for the 5/2 state is constructed according to this rule. copyright 1997 The American Physical Society
10. Skyrmion production on demand by homogeneous DC currents
Czech Academy of Sciences Publication Activity Database
Everschor-Sitte, K.; Sitte, M.; Valet, T.; Abanov, A.; Sinova, Jairo
2017-01-01
Roč. 19, Sep (2017), s. 1-5, č. článku 092001. ISSN 1367-2630 R&D Projects: GA ČR GB14-37427G; GA MŠk EF16_013/0001405 EU Projects: European Commission(XE) 610115 - SC2 Grant - others:OP VVV - LNSM(XE) CZ.02.1.01/0.0/0.0/16_013/0001405 Institutional support: RVO:68378271 Keywords : magnetization dynamics * micromagnetic simulations * skyrmions * thin films Subject RIV: BM - Solid Matter Physics ; Magnetism OBOR OECD: Condensed matter physics (including formerly solid state physics, supercond.) Impact factor: 3.786, year: 2016
11. Baby M: babies (and justice) for sale.
Science.gov (United States)
Annas, G J
1987-06-01
A professor of health law criticizes the decisions of New Jersey Superior Court Judge Harvey R. Sorkow which culminated in his awarding permanent custody of Baby M to her biological father, William Stern. Annas quotes from the In re Baby M decision and from the contract between Stern and his wife and surrogate mother Mary Beth Whitehead to support his contention that Sorkow "rendered a sermon filled with contradictions, double-standards, inapt analogies, and unsupported conclusions." He argues that legally Mrs. Whitehead could not have prospectively waived her right to rear a child she bore, that Sorkow was biased in favor of the "upper-middle-class Sterns," and that consideration should be given to returning Baby M to Mrs. Whitehead. He urges state legislatures to outlaw the sale of children, to affirm the legal status of the gestational mother, and to forbid a surrogate's relinquishment of parental rights until after her child's birth.
12. Smokefree After Baby
Science.gov (United States)
Many women quit smoking when they become pregnant. However, about 40 percent start smoking again 6 months after they have their baby. Quitting smoking has benefits for you and your baby that last longer than the 9 months of your pregnancy.
13. Grow, Baby, Grow
Science.gov (United States)
Maybe you quit smoking during your pregnancy. Or maybe you struggled and weren’t able to stay quit. Now that your baby is here, trying to stay away from smoking is still important. That’s because the chemicals in smoke can make it harder for your baby to grow like he or she should.
14. T P Nafeesa Baby
Home; Journals; Pramana – Journal of Physics. T P Nafeesa Baby. Articles written in Pramana – Journal of Physics. Volume 80 Issue 2 February 2013 pp 289-294 Research Articles. Plasma excitations in a single-walled carbon nanotube with an external transverse magnetic field · K A Vijayalakshmi T P Nafeesa Baby.
15. (AGA) Pre Term Babies
African Journals Online (AJOL)
Haematological Indices in Healthy Appropriate For-Gestational-Age (AGA) Pre Term Babies. ... International Journal of Medicine and Health Development. Journal Home ... Patient and Methods: All consecutive healthy pre-term new born babies delivered at UNTH and admitted into the hospital NBSCU were included.
16. CASE REPORT Mermaid baby
African Journals Online (AJOL)
SA JOURNAL OF RADIOLOGY • September 2010. Abstract. We were recently intrigued by a baby born at Kalafong Hospital with fused lower extremities resembling a mermaid, which caused us to search for the background and origin of this entity called sirenomelia. Case report. A 40-year-old woman delivered a baby at 36 ...
17. Shaken Baby Syndrome
Science.gov (United States)
... baby syndrome. Information from the National Library of Medicine’s MedlinePlus Child Abuse × What research is being done? The National ... baby syndrome. Information from the National Library of Medicine’s MedlinePlus Child Abuse See More About Research The National Institute ...
18. Baby Poop: What's Normal?
Science.gov (United States)
... I'm breast-feeding my newborn and her bowel movements are yellow and mushy. Is this normal for baby poop? Answers from Jay L. Hoecker, M.D. Yellow, mushy bowel movements are perfectly normal for breast-fed babies. Still, ...
19. Streamlined approach to mapping the magnetic induction of skyrmionic materials
International Nuclear Information System (INIS)
Chess, Jordan J.; Montoya, Sergio A.; Harvey, Tyler R.; Ophus, Colin; Couture, Simon; Lomakin, Vitaliy; Fullerton, Eric E.; McMorran, Benjamin J.
2017-01-01
Highlights: • A method to reconstruction the phase of electrons after pasting though a sample that requires a single defocused image is presented. • Restrictions as to when it is appropriate to apply this method are described. • The relative error associated with this method is compared to conventional transport of intensity equation analysis. - Abstract: Recently, Lorentz transmission electron microscopy (LTEM) has helped researchers advance the emerging field of magnetic skyrmions. These magnetic quasi-particles, composed of topologically non-trivial magnetization textures, have a large potential for application as information carriers in low-power memory and logic devices. LTEM is one of a very few techniques for direct, real-space imaging of magnetic features at the nanoscale. For Fresnel-contrast LTEM, the transport of intensity equation (TIE) is the tool of choice for quantitative reconstruction of the local magnetic induction through the sample thickness. Typically, this analysis requires collection of at least three images. Here, we show that for uniform, thin, magnetic films, which includes many skyrmionic samples, the magnetic induction can be quantitatively determined from a single defocused image using a simplified TIE approach.
20. Collective quantization of three-flavored Skyrmions reexamined
International Nuclear Information System (INIS)
Cherman, Aleksey; Cohen, Thomas D.; Dulaney, Timothy R.; Lynch, Erin M.
2005-01-01
A self-consistent large N c approach is developed for the collective quantization of SU(3) flavor hedgehog solitons, such as the Skyrmion. The key to this analysis is the determination of all of the zero-modes associated with small fluctuations around the hedgehog. These are used in the conventional way to construct collective coordinates. This approach differs from previous work in that it does not implicitly assume that each static zero-mode is associated with a dynamical zero-mode. It is demonstrated explicitly in the context of the Skyrmion that there are fewer dynamical zero-modes than static ones due to the Witten-Wess-Zumino term in the action. Group-theoretic methods are employed to identify the physical states resulting from canonical quantization of the collectively rotating soliton. The collective states fall into representations of SU(3) flavor labeled by (p,q) and are given by (2J,(Nc/2)-J) where J=(1/2),(3/2),··· is the spin of the collective state. States with strangeness S>0 do not arise as collective states from this procedure; thus the θ + (pentaquark) resonance does not arise as a collective excitation in models of this type
1. Streamlined approach to mapping the magnetic induction of skyrmionic materials
Energy Technology Data Exchange (ETDEWEB)
Chess, Jordan J., E-mail: jchess@uoregon.edu [Department of Physics, University of Oregon, Eugene, OR 97403 (United States); Montoya, Sergio A. [Center for Memory and Recording Research, University of California, San Diego, CA 92093 (United States); Department of Electrical and Computer Engineering, University of California, San Diego, La Jolla, CA 92093 (United States); Harvey, Tyler R. [Department of Physics, University of Oregon, Eugene, OR 97403 (United States); Ophus, Colin [National Center for Electron Microscopy, Molecular Foundry, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 94720 (United States); Couture, Simon; Lomakin, Vitaliy; Fullerton, Eric E. [Center for Memory and Recording Research, University of California, San Diego, CA 92093 (United States); Department of Electrical and Computer Engineering, University of California, San Diego, La Jolla, CA 92093 (United States); McMorran, Benjamin J. [Department of Physics, University of Oregon, Eugene, OR 97403 (United States)
2017-06-15
Highlights: • A method to reconstruction the phase of electrons after pasting though a sample that requires a single defocused image is presented. • Restrictions as to when it is appropriate to apply this method are described. • The relative error associated with this method is compared to conventional transport of intensity equation analysis. - Abstract: Recently, Lorentz transmission electron microscopy (LTEM) has helped researchers advance the emerging field of magnetic skyrmions. These magnetic quasi-particles, composed of topologically non-trivial magnetization textures, have a large potential for application as information carriers in low-power memory and logic devices. LTEM is one of a very few techniques for direct, real-space imaging of magnetic features at the nanoscale. For Fresnel-contrast LTEM, the transport of intensity equation (TIE) is the tool of choice for quantitative reconstruction of the local magnetic induction through the sample thickness. Typically, this analysis requires collection of at least three images. Here, we show that for uniform, thin, magnetic films, which includes many skyrmionic samples, the magnetic induction can be quantitatively determined from a single defocused image using a simplified TIE approach.
2. Partial twisting for scalar mesons
International Nuclear Information System (INIS)
Agadjanov, Dimitri; Meißner, Ulf-G.; Rusetsky, Akaki
2014-01-01
The possibility of imposing partially twisted boundary conditions is investigated for the scalar sector of lattice QCD. According to the commonly shared belief, the presence of quark-antiquark annihilation diagrams in the intermediate state generally hinders the use of the partial twisting. Using effective field theory techniques in a finite volume, and studying the scalar sector of QCD with total isospin I=1, we however demonstrate that partial twisting can still be performed, despite the fact that annihilation diagrams are present. The reason for this are delicate cancellations, which emerge due to the graded symmetry in partially quenched QCD with valence, sea and ghost quarks. The modified Lüscher equation in case of partial twisting is given
3. Spontaneous formation and dynamics of half-skyrmions in a chiral liquid-crystal film
Science.gov (United States)
Nych, Andriy; Fukuda, Jun-Ichi; Ognysta, Uliana; Žumer, Slobodan; Muševič, Igor
2017-12-01
Skyrmions are coreless vortex-like excitations emerging in diverse condensed-matter systems, and real-time observation of their dynamics is still challenging. Here we report the first direct optical observation of the spontaneous formation of half-skyrmions. In a thin film of a chiral liquid crystal, depending on experimental conditions including film thickness, they form a hexagonal lattice whose lattice constant is a few hundred nanometres, or appear as isolated entities with topological defects compensating their charge. These half-skyrmions exhibit intriguing dynamical behaviour driven by thermal fluctuations. Numerical calculations of real-space images successfully corroborate the experimental observations despite the challenge because of the characteristic scale of the structures close to the optical resolution limit. A thin film of a chiral liquid crystal thus offers an intriguing platform that facilitates a direct investigation of the dynamics of topological excitations such as half-skyrmions and their manipulation with optical techniques.
4. Aharonov–Bohm protection of black hole's baryon/skyrmion hair
Energy Technology Data Exchange (ETDEWEB)
Dvali, Gia [Arnold-Sommerfeld-Center for Theoretical Physics, Ludwig-Maximilians-Universität, 80333 München (Germany); Max-Planck-Institut für Physik, Werner-Heisenberg-Institut, 80805 München (Germany); Center for Cosmology and Particle Physics, Department of Physics, New York University, 4 Washington Place, New York, NY 10003 (United States); Gußmann, Alexander, E-mail: alexander.gussmann@physik.uni-muenchen.de [Arnold-Sommerfeld-Center for Theoretical Physics, Ludwig-Maximilians-Universität, 80333 München (Germany)
2017-05-10
The baryon/skyrmion correspondence implies that the baryon number is encoded into a topological surface integral. Under certain conditions that we clarify, this surface integral can be measured by an asymptotic observer in form of an Aharonov–Bohm phase-shift in an experiment in which the skyrmion passes through a loop of a probe string. In such a setup the baryon/skyrmion number must be respected by black holes, despite the fact that it produces no long-range classical field. If initially swallowed by a black hole, the baryon number must resurface in form of a classical skyrmion hair, after the black hole evaporates below a certain critical size. Needless to say, the respect of the baryon number by black holes is expected to have potentially-interesting astrophysical consequences.
5. Aharonov–Bohm protection of black hole's baryon/skyrmion hair
Directory of Open Access Journals (Sweden)
Gia Dvali
2017-05-01
Full Text Available The baryon/skyrmion correspondence implies that the baryon number is encoded into a topological surface integral. Under certain conditions that we clarify, this surface integral can be measured by an asymptotic observer in form of an Aharonov–Bohm phase-shift in an experiment in which the skyrmion passes through a loop of a probe string. In such a setup the baryon/skyrmion number must be respected by black holes, despite the fact that it produces no long-range classical field. If initially swallowed by a black hole, the baryon number must resurface in form of a classical skyrmion hair, after the black hole evaporates below a certain critical size. Needless to say, the respect of the baryon number by black holes is expected to have potentially-interesting astrophysical consequences.
6. Magnus-induced ratchet effects for skyrmions interacting with asymmetric substrates
Science.gov (United States)
Reichhardt, C.; Ray, D.; Olson Reichhardt, C. J.
2015-07-01
We show using numerical simulations that pronounced ratchet effects can occur for ac driven skyrmions moving over asymmetric quasi-one-dimensional substrates. We find a new type of ratchet effect called a Magnus-induced transverse ratchet that arises when the ac driving force is applied perpendicular rather than parallel to the asymmetry direction of the substrate. This transverse ratchet effect only occurs when the Magnus term is finite, and the threshold ac amplitude needed to induce it decreases as the Magnus term becomes more prominent. Ratcheting skyrmions follow ordered orbits in which the net displacement parallel to the substrate asymmetry direction is quantized. Skyrmion ratchets represent a new ac current-based method for controlling skyrmion positions and motion for spintronic applications.
7. Low-Field Bi-Skyrmion Formation in a Noncentrosymmetric Chimney Ladder Ferromagnet
Science.gov (United States)
Takagi, R.; Yu, X. Z.; White, J. S.; Shibata, K.; Kaneko, Y.; Tatara, G.; Rønnow, H. M.; Tokura, Y.; Seki, S.
2018-01-01
The real-space spin texture and the relevant magnetic parameters were investigated for an easy-axis noncentrosymmetric ferromagnet Cr11 Ge19 with Nowotny chimney ladder structure. Using Lorentz transmission electron microscopy, we report the formation of bi-Skyrmions, i.e., pairs of spin vortices with opposite magnetic helicities. The quantitative evaluation of the magnetocrystalline anisotropy and Dzyaloshinskii-Moriya interaction (DMI) proves that the magnetic dipolar interaction plays a more important role than the DMI on the observed bi-Skyrmion formation. Notably, the critical magnetic field value required for the formation of bi-Skyrmions turned out to be extremely small in this system, which is ascribed to strong easy-axis anisotropy associated with the characteristic helix crystal structure. The family of Nowotny chimney ladder compounds may offer a unique material platform where two distinctive Skyrmion formation mechanisms favoring different topological spin textures can become simultaneously active.
8. Skyrmion black hole hair: Conservation of baryon number by black holes and observable manifestations
Energy Technology Data Exchange (ETDEWEB)
Dvali, Gia [Arnold Sommerfeld Center, Ludwig-Maximilians-Universität, 80333 München (Germany); Max-Planck-Institut für Physik, Werner-Heisenberg-Institut, 80805 München (Germany); Center for Cosmology and Particle Physics, Department of Physics, New York University, 4 Washington Place, New York, NY 10003 (United States); Gußmann, Alexander, E-mail: alexander.gussmann@physik.uni-muenchen.de [Arnold Sommerfeld Center, Ludwig-Maximilians-Universität, 80333 München (Germany)
2016-12-15
We show that the existence of black holes with classical skyrmion hair invalidates standard proofs that global charges, such as the baryon number, cannot be conserved by a black hole. By carefully analyzing the standard arguments based on a Gedankenexperiment in which a black hole is seemingly-unable to return the baryon number that it swallowed, we identify inconsistencies in this reasoning, which does not take into the account neither the existence of skyrmion black holes nor the baryon/skyrmion correspondence. We then perform a refined Gedankenexperiment by incorporating the new knowledge and show that no contradiction with conservation of baryon number takes place at any stage of black hole evolution. Our analysis also indicates no conflict between semi-classical black holes and the existence of baryonic gauge interaction arbitrarily-weaker than gravity. Next, we study classical cross sections of a minimally-coupled massless probe scalar field scattered by a skyrmion black hole. We investigate how the skyrmion hair manifests itself by comparing this cross section with the analogous cross section caused by a Schwarzschild black hole which has the same ADM mass as the skyrmion black hole. Here we find an order-one difference in the positions of the characteristic peaks in the cross sections. The peaks are shifted to smaller scattering angles when the skyrmion hair is present. This comes from the fact that the skyrmion hair changes the near horizon geometry of the black hole when compared to a Schwarzschild black hole with same ADM mass. We keep the study of this second aspect general so that the qualitative results which we obtain can also be applied to black holes with classical hair of different kind.
9. Photophysics of internal twisting
International Nuclear Information System (INIS)
Heisel, F.; Miehe, J.A.; Lippert, E.; Rettig, W.; Bonacic-Koutecky, V.
1987-01-01
The formation and characteristics of the ''twisted intermolecular charge transfer'' is studied. Basic concepts on dual fluorescence, steady-state fluorescence, kinetic investigations and cage effects are discussed. The theoretical treatment on the electronic structure of the bonded π - donor - π acceptor pairs is outlined. The two-electron, two-orbital model, the ab initio CI models of simple double, charged and dative π - bonds as well as complex dative π - bonds and the origin of the dual fluorescence of 9.9'-Bianthryl are shown. Concerning the stochastic description of chemical reactions, Master equation, Markov, Birth-Death and Diffusion processes, Kramers-Moyal expansion, Langevin equation, Kramers' approach to steady-state rates of reaction and its extension to non-Markovian processes, and also unimolecular reactions in the absence of potential barrier are considered. Experimental results and interpretation on dynamics of DMABN in the excited state, kinetics of other dialkylanilines, extended donor-acceptor systems with anomalous fluorescence and donor-acceptor systems without anomalous fluorescence are given
10. Windings of twisted strings
Science.gov (United States)
Casali, Eduardo; Tourkine, Piotr
2018-03-01
Twistor string models have been known for more than a decade now but have come back under the spotlight recently with the advent of the scattering equation formalism which has greatly generalized the scope of these models. A striking ubiquitous feature of these models has always been that, contrary to usual string theory, they do not admit vibrational modes and thus describe only conventional field theory. In this paper we report on the surprising discovery of a whole new sector of one of these theories which we call "twisted strings," when spacetime has compact directions. We find that the spectrum is enhanced from a finite number of states to an infinite number of interacting higher spin massive states. We describe both bosonic and world sheet supersymmetric models, their spectra and scattering amplitudes. These models have distinctive features of both string and field theory, for example they are invariant under stringy T-duality but have the high energy behavior typical of field theory. Therefore they describe a new kind of field theories in target space, sitting on their own halfway between string and field theory.
11. Skyrmions and Novel Spin Textures in FeGe Thin Films and Artificial B20 Heterostructures
Science.gov (United States)
Skyrmions are magnetic spin textures that have a non-zero topological winding number associated with them. They have attracted much interest recently since they can be as small as 1 nm and could be the next generation of magnetic memory and logic. First, we grow epitaxial films of FeGe by molecular beam epitaxy and characterized the skyrmion properties. This had led us to image skyrmions in real-space with Lorentz transmission electron microscopy for the first time in the United States. Next, from an extensive series of thin and thick films, we have experimentally shown the existence of a magnetic surface state in FeGe and, consequently, any skyrmion material for the first time. Complementary theoretical calculations supported the existence of chiral bobbers--a surface state only predicted in 2015. Next, we fabricated for the first time a new class of skyrmion materials: B20 superlattices. These novel heterostructures of [FeGe/MnGe/CrGe] have now opened the door for tunable skyrmion systems with both Dresselhaus and Rashba Dzyaloshinskii-Moriya interactions. Additionally, we perform resonant soft x-ray scattering to image magnetic spin textures in reciprocal space for FeGe thin films in transmission. We have accomplished the removal of substrate and left an isolated single-crystal FeGe film. Lastly, SrO is grown on graphene as a crystalline, atomically smooth, and pinhole free tunnel barrier for spin injection.
12. Evolution of topological skyrmions across the spin reorientation transition in Pt/Co/Ta multilayers
Science.gov (United States)
He, Min; Li, Gang; Zhu, Zhaozhao; Zhang, Ying; Peng, Licong; Li, Rui; Li, Jianqi; Wei, Hongxiang; Zhao, Tongyun; Zhang, X.-G.; Wang, Shouguo; Lin, Shi-Zeng; Gu, Lin; Yu, Guoqiang; Cai, J. W.; Shen, Bao-gen
2018-05-01
Magnetic skyrmions in multilayers are particularly appealing as next generation memory devices due to their topological compact size, the robustness against external perturbations, the capability of electrical driving and detection, and the compatibility with the existing spintronic technologies. To date, Néel-type skyrmions at room temperature (RT) have been studied mostly in multilayers with easy-axis magnetic anisotropy. Here, we systematically broadened the evolution of magnetic skyrmions with sub-50-nm size in a series of Pt/Co/Ta multilayers where the magnetic anisotropy is tuned continuously from easy axis to easy plane by increasing the ferromagnetic Co layer thickness. The existence of nontrivial skyrmions is identified via the combination of in situ Lorentz transmission electron microscopy (L-TEM) and Hall transport measurements. A high density of magnetic skyrmions over a wide temperature range is observed in the multilayers with easy-plane anisotropy, which will stimulate further exploration for new materials and accelerate the development of skyrmion-based spintronic devices.
13. Ratchet Effects, Negative Mobility, and Phase Locking for Skyrmions on Periodic Substrates
Science.gov (United States)
Reichhardt, Charles; Ray, Dipanjan; Olson Reichhardt, Cynthia
We examine the dynamics of skyrmions interacting with 1D and 2D periodic substrates in the presence of dc and ac drives. We find that the Magnus term strongly affects the skyrmion dynamics and that new kinds of phenomena can occur which are absent for overdamped ac and dc driven particles interacting with similar substrates. We show that it is possible to realize a Magnus induced ratchet for skyrmions interacting with an asymmetric potential, where the application of an ac drive can produce quantized dc motion of the skyrmions even when the ac force is perpendicular to the substrate asymmetry direction. For symmetric substrates it is also possible to achieve a negative mobility effect where the net skyrmion motion runs counter to an applied dc drive. Here, as a function of increasing dc drive, the velocity-force curves show a series of locking phases that have different features from the classic Shapiro steps found in overdamped systems. In the phase locking and ratcheting states, the skyrmions undergo intricate 2D orbits induced by the Magnus term.
14. Healthy Smile for Your Baby
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... your baby is 1 year old before feeding him cow’s milk. m Hold your baby while feeding him breast milk or formula in a bottle. m ... your baby is 1 year old before giving him juice. m When your baby is around 4 ...
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Full Text Available ... Our work Community impact Global programs Research Need help? Frequently asked questions Contact us Tools & Resources Born ... your dashboard . Time to eat! Feeding your baby helps her grow healthy and strong. It’s also a ...
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Full Text Available ... baby Formula feeding How to breastfeed Keeping breast milk safe and healthy Problems and discomforts when breastfeeding ... health & safety ') document.write('') } Ask our experts! Have a ...
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... milk is easier to digest than formula. • Breast milk contains antibodies that protect infants from certain illnesses, such as ear infections, diarrhea, respiratory illnesses, and allergies. The longer your baby breastfeeds, ...
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Full Text Available ... Saving Just a moment, please. You've saved this page It's been added to your ... milk is the best food for your baby during the first year of life. Learn how to breastfeed and why ...
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Full Text Available ... discomforts . If you’re feeding your baby formula , find out how to choose the best one for ... care they receive. We're pioneering research to find solutions. We're empowering families with the knowledge ...
20. Babies Need Tummy Time
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... sharing on social media links Babies Need Tummy Time! Page Content Tummy Time is not only an ... of your baby’s normal growth. What Is Tummy Time? Tummy Time describes the times when you place ...
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Full Text Available ... this page It's been added to your dashboard . Time to eat! Feeding your baby helps her grow healthy and strong. It’s also a great time for you and your partner to bond with ...
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Full Text Available ... Content] March For Babies | Nacersano | Share Your Story Register | Sign In Hi | Your dashboard | sign out Donate ... DONATE sign up sign in sign out account center my dashboard Our Cause Our mission Fighting premature ...
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Full Text Available ... The Prematurity Campaign About us Annual report Our work Community impact Global programs Research Need help? Frequently ... for your baby during the first year of life. Learn how to breastfeed and why breast milk ...
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Full Text Available ... The Prematurity Campaign About us Annual report Our work Community impact Global programs Research Need help? Frequently ... bond with her. Breast milk is the best food for your baby during the first year of ...
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Full Text Available ... bond with her. Breast milk is the best food for your baby during the first year of ... feeding safe. And then get ready for solid foods ! In This Topic Breastfeeding help Breastfeeding is best ...
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Full Text Available ... us on Twitter Instagram: behind the scenes Our research Research grants Prematurity research Birth defects research Infant ... bond with her. Breast milk is the best food for your baby during the first year of ...
8. Potential implementation of reservoir computing models based on magnetic skyrmions
Science.gov (United States)
Bourianoff, George; Pinna, Daniele; Sitte, Matthias; Everschor-Sitte, Karin
2018-05-01
Reservoir Computing is a type of recursive neural network commonly used for recognizing and predicting spatio-temporal events relying on a complex hierarchy of nested feedback loops to generate a memory functionality. The Reservoir Computing paradigm does not require any knowledge of the reservoir topology or node weights for training purposes and can therefore utilize naturally existing networks formed by a wide variety of physical processes. Most efforts to implement reservoir computing prior to this have focused on utilizing memristor techniques to implement recursive neural networks. This paper examines the potential of magnetic skyrmion fabrics and the complex current patterns which form in them as an attractive physical instantiation for Reservoir Computing. We argue that their nonlinear dynamical interplay resulting from anisotropic magnetoresistance and spin-torque effects allows for an effective and energy efficient nonlinear processing of spatial temporal events with the aim of event recognition and prediction.
9. Twisting the N=2 string
International Nuclear Information System (INIS)
Ketov, S.V.; Lechtenfeld, O.; Parkes, A.J.
1993-12-01
The most general homogeneous monodromy conditions in N= 2 string theory are classified in terms of the conjugacy classes of the global symmetry group U(1, 1) x Z 2 . For classes which generate a discrete subgroup Γ, the corresponding target space backgrounds C 1,1 /Γ include half spaces, complex orbifolds and tori. We propose a generalization of the intercept formula to matrix-valued twists, and find massless physical states in a number of twisted cases. In particular, the sixteen Z 2 -twisted sectors of the N = 2 string are investigated, and the corresponding ground states are identified via bosonization and BRST cohomology. We find enough room for an extended multiplet of 'spacetime' supersymmetry, with the number of supersymmetries being dependent on global 'spacetime' topology. Unfortunately, world-sheet locality for the chiral vertex operators does not permit interactions for the massless 'spacetime' fermions; however possibly, an asymmetric GSO projection could evade this problem. (orig.)
10. Baby brain atlases.
Science.gov (United States)
Oishi, Kenichi; Chang, Linda; Huang, Hao
2018-04-03
The baby brain is constantly changing due to its active neurodevelopment, and research into the baby brain is one of the frontiers in neuroscience. To help guide neuroscientists and clinicians in their investigation of this frontier, maps of the baby brain, which contain a priori knowledge about neurodevelopment and anatomy, are essential. "Brain atlas" in this review refers to a 3D-brain image with a set of reference labels, such as a parcellation map, as the anatomical reference that guides the mapping of the brain. Recent advancements in scanners, sequences, and motion control methodologies enable the creation of various types of high-resolution baby brain atlases. What is becoming clear is that one atlas is not sufficient to characterize the existing knowledge about the anatomical variations, disease-related anatomical alterations, and the variations in time-dependent changes. In this review, the types and roles of the human baby brain MRI atlases that are currently available are described and discussed, and future directions in the field of developmental neuroscience and its clinical applications are proposed. The potential use of disease-based atlases to characterize clinically relevant information, such as clinical labels, in addition to conventional anatomical labels, is also discussed. Copyright © 2018. Published by Elsevier Inc.
11. Introduction to twisted conformal fields
International Nuclear Information System (INIS)
Kazama, Y.
1988-01-01
A pedagogical account is given of the recent developments in the theory of twisted conformal fields. Among other things, the main part of the lecture concerns the construction of the twist-emission vertex operator, which is a generalization of the fermion emission vertex in the superstring theory. Several different forms of the vertex are derived and their mutural relationships are clarified. In this paper, the authors include a brief survey of the history of the fermion emission vertex, as it offers a good perspective in which to appreciate the logical development
12. [Babies with cranial deformity].
Science.gov (United States)
Feijen, Michelle M W; Claessens, Edith A W M Habets; Dovens, Anke J Leenders; Vles, Johannes S; van der Hulst, Rene R W J
2009-01-01
Plagiocephaly was diagnosed in a baby aged 4 months and brachycephaly in a baby aged 5 months. Positional or deformational plagio- or brachycephaly is characterized by changes in shape and symmetry of the cranial vault. Treatment options are conservative and may include physiotherapy and helmet therapy. During the last two decades the incidence of positional plagiocephaly has increased in the Netherlands. This increase is due to the recommendation that babies be laid on their backs in order to reduce the risk of sudden infant death syndrome. We suggest the following: in cases of positional preference of the infant, referral to a physiotherapist is indicated. In cases of unacceptable deformity of the cranium at the age 5 months, moulding helmet therapy is a possible treatment option.
13. Waveguides with asymptotically diverging twisting
Czech Academy of Sciences Publication Activity Database
Krejčiřík, David
2015-01-01
Roč. 46, AUG (2015), s. 7-10 ISSN 0893-9659 R&D Projects: GA ČR(CZ) GA14-06818S Institutional support: RVO:61389005 Keywords : quantum waveguide * exploding twisting * Quasi-bounded * Quasi-cylindrical * discrete spectrum Subject RIV: BE - Theoretical Physics Impact factor: 1.659, year: 2015
14. Obstructions for twist star products
Science.gov (United States)
Bieliavsky, Pierre; Esposito, Chiara; Waldmann, Stefan; Weber, Thomas
2018-05-01
In this short note, we point out that not every star product is induced by a Drinfel'd twist by showing that not every Poisson structure is induced by a classical r-matrix. Examples include the higher genus symplectic Pretzel surfaces and the symplectic sphere S^2.
15. Your baby and the flu
Science.gov (United States)
Babies and the flu; Your infant and the flu; Your toddler and the flu ... FLU SYMPTOMS IN INFANTS AND TODDLERS The flu is an infection of the nose, throat, and (sometimes) lungs. Call your baby's provider if ...
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17. Salmonella from Baby Turtles
Centers for Disease Control (CDC) Podcasts
2017-01-09
Dr. Stacey Bosch, a veterinarian with CDC, discusses her article on Salmonella infections associated with baby turtles. Created: 1/9/2017 by National Center for Emerging and Zoonotic Infectious Diseases (NCEZID). Date Released: 1/9/2017.
18. Spitting Up in Babies
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... be done. If your baby’s reflux is causing health problems, your doctor may prescribe medicine. This medicine is the same ... Is my baby at risk for any health problems? Last Updated: February 8, 2018 ... of Family Physicians This information provides a general overview and may ...
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Full Text Available ... Global Map Premature Birth Report Cards Careers Archives Pregnancy Before or between pregnancies Nutrition, weight & fitness Prenatal care Is it safe? ... Feeding your baby Family health & safety Complications & Loss Pregnancy complications Preterm labor & premature birth The newborn intensive ...
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Full Text Available ... Product Catalog Volunteer Volunteer leaders Team Youth National service partners ... strong. It’s also a great time for you and your partner to bond with her. Breast milk is the best food for your baby during the first year of ...
1. How Babies Think
Science.gov (United States)
Bachleda, Amelia R.; Thompson, Ross A.
2018-01-01
Babies think differently than adults, and understanding how they think can help us see their explosive brain growth in everyday behavior. Infants learn language faster than adults do, use statistics to understand how the world works, and even reason about the minds of others. But these achievements can be hidden by their poor self-regulatory…
2. Choosing Safe Baby Gear
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... wipes within your reach, but out of your baby’s reach. Car seat: The law requires drivers to place a child in a car seat designed for the child’s age, weight, and height. These requirements can vary by state and include: Rear-facing car seats for babies up to age 2. Forward-facing car seats ...
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Full Text Available ... intensive care unit (NICU) Birth defects & other health conditions Loss & grief ... health of all moms and babies. We're advocating for policies to protect them. We're working to radically improve the health care they receive. ...
4. Twist deformations of the supersymmetric quantum mechanics
Energy Technology Data Exchange (ETDEWEB)
Castro, P.G.; Chakraborty, B.; Toppan, F., E-mail: pgcastro@cbpf.b, E-mail: biswajit@bose.res.i, E-mail: toppan@cbpf.b [Centro Brasileiro de Pesquisas Fisicas (CBPF), Rio de Janeiro, RJ (Brazil); Kuznetsova, Z., E-mail: zhanna.kuznetsova@ufabc.edu.b [Universidade Federal do ABC (UFABC), Santo Andre, SP (Brazil)
2009-07-01
The N-extended supersymmetric quantum mechanics is deformed via an abelian twist which preserves the super-Hopf algebra structure of its universal enveloping superalgebra. Two constructions are possible. For even N one can identify the 1D N-extended superalgebra with the fermionic Heisenberg algebra. Alternatively, supersymmetry generators can be realized as operators belonging to the Universal Enveloping Superalgebra of one bosonic and several fermionic oscillators. The deformed system is described in terms of twisted operators satisfying twist deformed (anti)commutators. The main differences between an abelian twist defined in terms of fermionic operators and an abelian twist defined in terms of bosonic operators are discussed. (author)
5. Noncommutative geometry and twisted conformal symmetry
International Nuclear Information System (INIS)
Matlock, Peter
2005-01-01
The twist-deformed conformal algebra is constructed as a Hopf algebra with twisted coproduct. This allows for the definition of conformal symmetry in a noncommutative background geometry. The twisted coproduct is reviewed for the Poincare algebra and the construction is then extended to the full conformal algebra. The case of Moyal-type noncommutativity of the coordinates is considered. It is demonstrated that conformal invariance need not be viewed as incompatible with noncommutative geometry; the noncommutativity of the coordinates appears as a consequence of the twisting, as has been shown in the literature in the case of the twisted Poincare algebra
6. Boosting Your Baby's Brain Power
Science.gov (United States)
Engel-Smothers, Holly; Heim, Susan M.
2009-01-01
With more than 100 billion neurons that would stretch more than 60,000 miles, a newborn baby's brain is quite phenomenal! These neurons must generally form connections within the first eight months of a baby's life to foster optimal brain growth and lifelong learning. Mommies, daddies, and caregivers are extremely vital to ensuring babies reach…
7. Baby Naps: Daytime Sleep Tips
Science.gov (United States)
... won't harm your baby. It's common for babies to cry when put down for sleep, but most will quiet themselves if left alone for a few minutes. If the crying lasts longer than a few minutes, check on your baby and offer comforting words. Then give him or ...
8. Negative baryon density and the folding structure of the B = 3 skyrmion
International Nuclear Information System (INIS)
Foster, D; Krusch, S
2013-01-01
The Skyrme model is a nonlinear field theory whose solitonic solutions, once quantized, describe atomic nuclei. The classical static soliton solutions, so-called skyrmions, have interesting symmetries and can only be calculated numerically. Mathematically, these skyrmions can be viewed as maps between two three-manifolds and, as such, their stable singularities can only be folds, cusps and swallowtails. Physically, the occurrence of singularities is related to negative baryon density. In this paper, we calculate the charge three skyrmion to a high resolution in order to examine its singularity structure in detail. Thereby, we explore regions of negative baryon density. We also discuss how the negative baryon density depends on the pion mass. (paper)
9. Theory of Topological Spin Hall Effect in Antiferromagnetic Skyrmion: Impact on Current-induced Motion
KAUST Repository
Akosa, Collins Ashu
2017-09-09
We demonstrate that the nontrivial magnetic texture of antiferromagnetic skyrmions (AFM-Sks) promotes a non-vanishing topological spin Hall effect (TSHE) on the flowing electrons. This results in a substantial enhancement of the non-adiabatic torque and hence improves the skyrmion mobility. This non-adiabatic torque increases when decreasing the skyrmion size, and therefore scaling down results in a much higher torque efficiency. In clean AFM-Sks, we find a significant boost of the TSHE close to van Hove singularity. Interestingly, this effect is enhanced away from the band gap in the presence of non-magnetic interstitial defects. Furthermore, unlike their ferromagnetic counterpart, TSHE in AFM-Sks increases with increase in disorder strength thus opening promising avenues for materials engineering of this effect.
10. Field-free deterministic ultrafast creation of magnetic skyrmions by spin-orbit torques
Science.gov (United States)
Büttner, Felix; Lemesh, Ivan; Schneider, Michael; Pfau, Bastian; Günther, Christian M.; Hessing, Piet; Geilhufe, Jan; Caretta, Lucas; Engel, Dieter; Krüger, Benjamin; Viefhaus, Jens; Eisebitt, Stefan; Beach, Geoffrey S. D.
2017-11-01
Magnetic skyrmions are stabilized by a combination of external magnetic fields, stray field energies, higher-order exchange interactions and the Dzyaloshinskii-Moriya interaction (DMI). The last favours homochiral skyrmions, whose motion is driven by spin-orbit torques and is deterministic, which makes systems with a large DMI relevant for applications. Asymmetric multilayers of non-magnetic heavy metals with strong spin-orbit interactions and transition-metal ferromagnetic layers provide a large and tunable DMI. Also, the non-magnetic heavy metal layer can inject a vertical spin current with transverse spin polarization into the ferromagnetic layer via the spin Hall effect. This leads to torques that can be used to switch the magnetization completely in out-of-plane magnetized ferromagnetic elements, but the switching is deterministic only in the presence of a symmetry-breaking in-plane field. Although spin-orbit torques led to domain nucleation in continuous films and to stochastic nucleation of skyrmions in magnetic tracks, no practical means to create individual skyrmions controllably in an integrated device design at a selected position has been reported yet. Here we demonstrate that sub-nanosecond spin-orbit torque pulses can generate single skyrmions at custom-defined positions in a magnetic racetrack deterministically using the same current path as used for the shifting operation. The effect of the DMI implies that no external in-plane magnetic fields are needed for this aim. This implementation exploits a defect, such as a constriction in the magnetic track, that can serve as a skyrmion generator. The concept is applicable to any track geometry, including three-dimensional designs.
11. Renormalization constants for 2-twist operators in twisted mass QCD
International Nuclear Information System (INIS)
Alexandrou, C.; Constantinou, M.; Panagopoulos, H.; Stylianou, F.; Korzec, T.
2011-01-01
Perturbative and nonperturbative results on the renormalization constants of the fermion field and the twist-2 fermion bilinears are presented with emphasis on the nonperturbative evaluation of the one-derivative twist-2 vector and axial-vector operators. Nonperturbative results are obtained using the twisted mass Wilson fermion formulation employing two degenerate dynamical quarks and the tree-level Symanzik improved gluon action. The simulations have been performed for pion masses in the range of about 450-260 MeV and at three values of the lattice spacing a corresponding to β=3.9, 4.05, 4.20. Subtraction of O(a 2 ) terms is carried out by performing the perturbative evaluation of these operators at 1-loop and up to O(a 2 ). The renormalization conditions are defined in the RI ' -MOM scheme, for both perturbative and nonperturbative results. The renormalization factors, obtained for different values of the renormalization scale, are evolved perturbatively to a reference scale set by the inverse of the lattice spacing. In addition, they are translated to MS at 2 GeV using 3-loop perturbative results for the conversion factors.
12. Effects of second neighbor interactions on skyrmion lattices in chiral magnets
International Nuclear Information System (INIS)
Oliveira, E A S; Silva, R L; Silva, R C; Pereira, A R
2017-01-01
In this paper we investigate the influences of the second neighbor interactions on a skyrmion lattice in two-dimensional chiral magnets. Such a system contains the exchange and the Dzyaloshinskii–Moriya for the spin interactions and therefore, we analyse three situations: firstly, the second neighbor interaction is present only in the exchange coupling; secondly, it is present only in the Dzyaloshinskii–Moriya coupling. Finally, the second neighbor interactions are present in both exchange and Dzyaloshinskii–Moriya couplings. We show that such effects cause important modifications to the helical and skyrmion phases when an external magnetic field is applied. (paper)
13. Thermal effects on current-related skyrmion formation in a nanobelt
Science.gov (United States)
Zhao, Xuebing; Wang, Shasha; Wang, Chao; Che, Renchao
2018-05-01
We report an in-situ Lorentz transmission electron microscopy (LTEM) investigation to study the thermal effects on the generation of magnetic skyrmions within a nanobelt. Under an action of a moderate current pulse, magnetic skyrmions appear even in the temperature range far below the critical temperature and even at zero field. Finite element simulation reveals that the Joule heating plays an essential role in this behavior. Our results also uncover the importance of the cooling conditions in the current-related in situ LTEM research.
14. Transmutation of skyrmions to half-solitons driven by the nonlinear optical spin Hall effect.
Science.gov (United States)
Flayac, H; Solnyshkov, D D; Shelykh, I A; Malpuech, G
2013-01-04
We show that the spin domains, generated in the linear optical spin Hall effect by the analog of spin-orbit interaction for exciton polaritons, are associated with the formation of a Skyrmion lattice. In the nonlinear regime, the spin anisotropy of the polariton-polariton interactions results in a spatial compression of the domains and in a transmutation of the Skyrmions into oblique half-solitons. This phase transition is associated with both the focusing of the spin currents and the emergence of a strongly anisotropic emission pattern.
15. Effective potentials for twisted fields
International Nuclear Information System (INIS)
Banach, R.
1981-01-01
Minus the density of the effective action, evaluated at the lowest eigenfunction of the (space-time) derivative part of the second (functional) derivative of the classical action, is proposed as a generalised definition of the effective potential, applicable to twisted as well as untwisted sectors of a field theory. The proposal is corroborated by several specific calculations in the twisted sector, namely phi 4 theory (real and complex) and wrong-sign-Gordon theory, in an Einstein cylinder, where the exact integrability of the static solutions confirms the effective potential predictions. Both models exhibit a phase transition, which the effective potential locates, and the one-loop quantum shift in the critical radius is computed for the real phi 4 model, being a universal result. Topological mass generation at the classical level is pointed out, and the exactness of the classical effective potential approximation for complex phi 4 is discussed. (author)
16. Creation of Single Chain of Nanoscale Skyrmion Bubbles with Record-high Temperature Stability in a Geometrically Confined Nanostripe
KAUST Repository
Hou, Zhipeng; Zhang, Qiang; Xu, Guizhou; Gong, Chen; Ding, Bei; Wang, Yue; Li, Hang; Liu, Enke; Xu, Feng; Zhang, Hongwei; Yao, Yuan; Wu, Guangheng; Zhang, Xixiang; Wang, Wenhong
2018-01-01
Nanoscale topologically nontrivial spin textures, such as magnetic skyrmions, have been identified as promising candidates for the transport and storage of information for spintronic applications, notably magnetic racetrack memory devices. The design and realization of a single skyrmion chain at room temperature (RT) and above in the low-dimensional nanostructures are of great importance for future practical applications. Here, we report the creation of a single skyrmion bubble chain in a geometrically confined Fe3Sn2 nanostripe with a width comparable to the featured size of a skyrmion bubble. Systematic investigations on the thermal stability have revealed that the single chain of skyrmion bubbles can keep stable at temperatures varying from RT up to a record-high temperature of 630 K. This extreme stability can be ascribed to the weak temperature-dependent magnetic anisotropy and the formation of edge states at the boundaries of the nanostripes. The realization of the highly stable skyrmion bubble chain in a geometrically confined nanostructure is a very important step toward the application of skyrmion-based spintronic devices.
17. Creation of Single Chain of Nanoscale Skyrmion Bubbles with Record-high Temperature Stability in a Geometrically Confined Nanostripe
KAUST Repository
Hou, Zhipeng
2018-01-04
Nanoscale topologically nontrivial spin textures, such as magnetic skyrmions, have been identified as promising candidates for the transport and storage of information for spintronic applications, notably magnetic racetrack memory devices. The design and realization of a single skyrmion chain at room temperature (RT) and above in the low-dimensional nanostructures are of great importance for future practical applications. Here, we report the creation of a single skyrmion bubble chain in a geometrically confined Fe3Sn2 nanostripe with a width comparable to the featured size of a skyrmion bubble. Systematic investigations on the thermal stability have revealed that the single chain of skyrmion bubbles can keep stable at temperatures varying from RT up to a record-high temperature of 630 K. This extreme stability can be ascribed to the weak temperature-dependent magnetic anisotropy and the formation of edge states at the boundaries of the nanostripes. The realization of the highly stable skyrmion bubble chain in a geometrically confined nanostructure is a very important step toward the application of skyrmion-based spintronic devices.
18. Twisting formula of epsilon factors
2017-08-07
Aug 7, 2017 ... In this article, we give a generalized twisting formula for ϵ(χ1χ2,ψ), when both χ1 and χ2 are ramified via the following local Jacobi sums. Let UF be the group of units in OF (ring of integers of F). For characters χ1, χ2 of F. × and a positive integer n, we define the local Jacobi sum. Jt(χ1,χ2, n) = ∑ x∈UF. Un.
19. Shaken baby syndrome; Shaken-baby-Syndrom
Energy Technology Data Exchange (ETDEWEB)
Reith, W.; Ahlhelm, F.; Papanagiotou, P. [Universitaetsklinikum des Saarlandes, Klinik fuer Diagnostische und Interventionelle Neuroradiologie, Homburg/Saar (Germany); Rohrer, T. [Universitaetsklinikum des Saarlandes, Klinik fuer Allgemeine Paediatrie und Neonatologie, Homburg/Saar (Germany)
2009-10-15
Shaken baby syndrome (SBS) describes the coincidence of subdural hematoma, retinal bleeding and, disadvantageous for the prognosis, diffuse brain damage caused by powerful shaking of the infant. The clinical symptoms include irritability, difficulty with drinking, somnolence, apathy, cerebral cramp attacks, apnoea, temperature regulation disorders and vomiting due to cranial pressure. Milder symptoms of SBS are often not diagnosed and the number of unregistered cases is probably much greater. The diagnosis of SBS is made through the typical symptom constellation, but the lack of retinal bleeding does not exclude the diagnosis. Normally the infants are held by the thorax or upper arms and shaken in a sagittal direction during which the head falls backwards and forwards and is stopped abruptly at each extreme position. The injurious mechanism is considered to be caused by rotational forces which force tissue layers in the brain against each other and also lead to rupture of bridging veins between the skull and the brain. The prognosis is poor and approximately 25% of infants die of SBS within days or weeks. Approximately 75% of survivors suffer from long term damage with physical handicaps, limitations in hearing, visual disturbances up to blindness and mental disorders or combinations of these conditions. Prevention is therefore the most important aspect. (orig.) [German] Das Shaken-baby-Syndrom (SBS) oder Schuetteltrauma des Saeuglings beschreibt die Koinzidenz subduraler Haematome, retinaler Blutungen und prognostisch unguenstiger, diffuser Hirnschaeden durch heftiges Schuetteln eines Saeuglings. Die klinischen Symptome umfassen Irritabilitaet, Trinkschwierigkeiten, Somnolenz, Apathie, zerebrale Krampfanfaelle, Apnoe, Temperaturregulationsstoerungen und Erbrechen durch Hirndruck. Leichtere Symptome des SBS werden haeufig nicht diagnostiziert, die Dunkelziffer ist wahrscheinlich viel hoeher. Die Diagnose des SBS wird durch die typische Symptomkonstellation gestellt
20. New twist on artificial muscles.
Science.gov (United States)
Haines, Carter S; Li, Na; Spinks, Geoffrey M; Aliev, Ali E; Di, Jiangtao; Baughman, Ray H
2016-10-18
Lightweight artificial muscle fibers that can match the large tensile stroke of natural muscles have been elusive. In particular, low stroke, limited cycle life, and inefficient energy conversion have combined with high cost and hysteretic performance to restrict practical use. In recent years, a new class of artificial muscles, based on highly twisted fibers, has emerged that can deliver more than 2,000 J/kg of specific work during muscle contraction, compared with just 40 J/kg for natural muscle. Thermally actuated muscles made from ordinary polymer fibers can deliver long-life, hysteresis-free tensile strokes of more than 30% and torsional actuation capable of spinning a paddle at speeds of more than 100,000 rpm. In this perspective, we explore the mechanisms and potential applications of present twisted fiber muscles and the future opportunities and challenges for developing twisted muscles having improved cycle rates, efficiencies, and functionality. We also demonstrate artificial muscle sewing threads and textiles and coiled structures that exhibit nearly unlimited actuation strokes. In addition to robotics and prosthetics, future applications include smart textiles that change breathability in response to temperature and moisture and window shutters that automatically open and close to conserve energy.
1. Baby universe theory
International Nuclear Information System (INIS)
Nielsen, H.B.; Ninomiya, Masao
1989-12-01
We give an elementary review of the so called 'the theory of baby universes' which is a series of ideas or speculations about some effects in quantum gravity, viz. the effect of a certain type of wormholes, representing the exchange of small 3-space universes called baby universes. We consider this 'theory' as being physically and scientifically a very promising candidate for a theory of everything. It is, however, mathematically lacking any strong foundation at all. It solves several fine-tuning problems: First of all the cosmological constant problem, and also the strong CP-problem and the hierarchy problem. We also speculate that it might predict the possibility of influencing the probability distributions of the outcome of quantum mechanical measurements at one time by acts at a later time. (orig.)
2. Ice, Ice, Baby!
Science.gov (United States)
Hamilton, C.
2008-12-01
The Center for Remote Sensing of Ice Sheets (CReSIS) has developed an outreach program based on hands-on activities called "Ice, Ice, Baby". These lessons are designed to teach the science principles of displacement, forces of motion, density, and states of matter. These properties are easily taught through the interesting topics of glaciers, icebergs, and sea level rise in K-8 classrooms. The activities are fun, engaging, and simple enough to be used at science fairs and family science nights. Students who have participated in "Ice, Ice, Baby" have successfully taught these to adults and students at informal events. The lessons are based on education standards which are available on our website www.cresis.ku.edu. This presentation will provide information on the activities, survey results from teachers who have used the material, and other suggested material that can be used before and after the activities.
3. Michelin tire baby syndrome
Directory of Open Access Journals (Sweden)
Rita V Vora
2016-01-01
Full Text Available Michelin tire baby syndrome (MTBS, is a rare genodermatosis, characterized by generalized folding of excess skin and may be associated with various phenotypic abnormalities. The pathogenesis of this condition is unclear. Various congenital anomalies can be associated with it. It may be a clinical finding associated with various syndromes. Diagnosis is mainly clinical, and skin folds gradually diminish and disappear with age without any intervention. Here, we report a case of MTBS associated with convergent squint and hydrocephaly.
4. LAMELLAR ICHTHYOSIS (COLLODION BABY
Directory of Open Access Journals (Sweden)
Paramarta IGE
2012-11-01
Full Text Available The ichthyosis are a heterogeneous group of hereditary and acquired disorder of keratinization which affected the epidermis characterized by presence of visible scales on the skin surface in the absence of inflammation. It can occur as a disease limited to the skin or in association with abnormalities of other organ systems. Lamelar ihthyosis (LI is one of two mayor autosomal recessive ichthyosis with an incidence of approximately one in 300,000. The diagnosis is based on clinical and pathologic finding. Infection is the most common complication, while prognosis of LI is depends on severity and complication of the disease. A case of lamellar ichthyosis in 0 day Balinese female baby was reported. The skin of the body was thick, plate-like appearance, scaling on the entire body, some of the thick skin was ruptured on chest and extremities. There were eclabium on the mouth and ectropion on the eyes. Histopathology examination showed hyperkeratosis without perivascular infiltration lymphocyte. The baby was given breast feeding, antibiotic, hydrocortisone cream and olium olivarum. The prognosis of the baby is good.
5. Modeling and control of active twist aircraft
Science.gov (United States)
Cramer, Nicholas Bryan
The Wright Brothers marked the beginning of powered flight in 1903 using an active twist mechanism as their means of controlling roll. As time passed due to advances in other technologies that transformed aviation the active twist mechanism was no longer used. With the recent advances in material science and manufacturability, the possibility of the practical use of active twist technologies has emerged. In this dissertation, the advantages and disadvantages of active twist techniques are investigated through the development of an aeroelastic modeling method intended for informing the designs of such technologies and wind tunnel testing to confirm the capabilities of the active twist technologies and validate the model. Control principles for the enabling structural technologies are also proposed while the potential gains of dynamic, active twist are analyzed.
6. Twisting dependent properties of twisted carbon nanotube fibers: microstructure and strain transfer factors
International Nuclear Information System (INIS)
Zhou, Jinyuan; Xie, Erqing; Sun, Gengzhi; Zhan, Zhaoyao; Zheng, Lianxi
2014-01-01
The dependences of twisting parameters on the electric and mechanical properties of twisted CNT fibers were systematically studied. Results from electric and mechanical measurements showed that twisting intensity is very effective to improve the electric and mechanical properties of CNT fibers. Further calculations combined with Raman results indicate that the twisting treatments, to a certain extent, can greatly enhance the strain transfer factors of the samples, which dominates the mechanical properties of CNT fibers. In addition, studies on the effect of twisting speeds suggested that lower twisting speed can lead to higher uniformity but lower performances in the electric and mechanical properties, higher twisting speed to higher Young’s modulus and higher conductance but lower uniformities. Ultra-strong uniform CNT fibers need to be prepared with a suitable twisting speed. (paper)
7. Recognition of a Baby's Emotional Cry towards Robotics Baby Caregiver
Directory of Open Access Journals (Sweden)
Shota Yamamoto
2013-02-01
Full Text Available We developed a method for pattern recognition of baby's emotions (discomfortable, hungry, or sleepy expressed in the baby's cries. A 32-dimensional fast Fourier transform is performed for sound form clips, detected by our reported method and used as training data. The power of the sound form judged as a silent region is subtracted from each power of the frequency element. The power of each frequency element after the subtraction is treated as one of the elements of the feature vector. We perform principal component analysis (PCA for the feature vectors of the training data. The emotion of the baby is recognized by the nearest neighbor criterion applied to the feature vector obtained from the test data of sound form clips after projecting the feature vector on the PCA space from the training data. Then, the emotion with the highest frequency among the recognition results for a sound form clip is judged as the emotion expressed by the baby's cry. We successfully applied the proposed method to pattern recognition of baby's emotions. The present investigation concerns the first stage of the development of a robotics baby caregiver that has the ability to detect baby's emotions. In this first stage, we have developed a method for detecting baby's emotions. We expect that the proposed method could be used in robots that can help take care of babies.
8. Topological dynamics and current-induced motion in a skyrmion lattice
Science.gov (United States)
Martinez, J. C.; Jalil, M. B. A.
2016-03-01
We study the Thiele equation for current-induced motion in a skyrmion lattice through two soluble models of the pinning potential. Comprised by a Magnus term, a dissipative term and a pinning force, Thiele’s equation resembles Newton’s law but in virtue of the topological character to the first, it differs significantly from Newtonian mechanics and because the Magnus force is dominant, unlike its mechanical counterpart—the Coriolis force—skyrmion trajectories do not necessarily have mechanical counterparts. This is important if we are to understand skyrmion dynamics and tap into its potential for data-storage technology. We identify a pinning threshold velocity for the one-dimensional pinning potential and for a two-dimensional attractive potential we find a pinning point and the skyrmion trajectories toward that point are spirals whose frequency (compare Kepler’s second law) and amplitude-decay depend only on the Gilbert constant and potential at the pinning point. Other scenarios, e.g. other choices of initial spin velocity, a repulsive potential, etc are also investigated.
9. Topological dynamics and current-induced motion in a skyrmion lattice
International Nuclear Information System (INIS)
Martinez, J C; Jalil, M B A
2016-01-01
We study the Thiele equation for current-induced motion in a skyrmion lattice through two soluble models of the pinning potential. Comprised by a Magnus term, a dissipative term and a pinning force, Thiele’s equation resembles Newton’s law but in virtue of the topological character to the first, it differs significantly from Newtonian mechanics and because the Magnus force is dominant, unlike its mechanical counterpart—the Coriolis force—skyrmion trajectories do not necessarily have mechanical counterparts. This is important if we are to understand skyrmion dynamics and tap into its potential for data-storage technology. We identify a pinning threshold velocity for the one-dimensional pinning potential and for a two-dimensional attractive potential we find a pinning point and the skyrmion trajectories toward that point are spirals whose frequency (compare Kepler’s second law) and amplitude-decay depend only on the Gilbert constant and potential at the pinning point. Other scenarios, e.g. other choices of initial spin velocity, a repulsive potential, etc are also investigated. (paper)
10. Creation and Annihilation of Skyrmions in the Frustrated Magnets with Competing Exchange Interactions.
Science.gov (United States)
Hu, Yong; Chi, Xiaodan; Li, Xuesi; Liu, Yan; Du, An
2017-11-22
In triangular-lattice magnets, the coexistence of third-neighbor antiferromagnetic and nearest-neighbor ferromagnetic exchange interactions can induce rich magnetic phases including noncoplanar skyrmion crystals. Based on Monte Carlo simulation, we studied the dependence of magnetic phase transition on exchange interaction strength. Under the consideration of uniaxial anisotropy and magnetic field both perpendicular to the film plane, a large antiferromagnetic exchange interaction induces a high frustration. When the value of antiferromagnetic exchange interaction is one and a half times larger than the ferromagnetic one, a magnetic phase composed of canting spin stripes, never observed in the chiral magnets, forms. Interestingly, different canting spin stripes along three 120 degree propagation directions may coexist randomly in a magnetic phase, attesting that the canting spin stripes are three-fold degenerate states akin to helices and the multiple state of canting spin stripes is a circular configuration with zero skyrmion charge number. Moreover, skyrmions and antiskyrmions can be observed simultaneously in the configuration at the low temperature nearly close to 0 K, and their configuration and diameter properties are discussed. Finally, the mechanisms of skyrmion creation and annihilation are properly interpreted by comparing exchange and Zeeman energy terms.
11. Dynamics of skyrmions and edge states in the resistive regime of mesoscopic p-wave superconductors
Energy Technology Data Exchange (ETDEWEB)
Fernández Becerra, V., E-mail: VictorLeonardo.FernandezBecerra@uantwerpen.be; Milošević, M.V., E-mail: milorad.milosevic@uantwerpen.be
2017-02-15
Highlights: • Voltage–current characterization of a mesoscopic p-wave superconducting sample. • Skyrmions and edge states are stabilized with an out-of-plane applied magnetic field. • In the resistive regime, moving skyrmions and the edge state behave distinctly different from the conventional kinematic vortices. - Abstract: In a mesoscopic sample of a chiral p-wave superconductor, novel states comprising skyrmions and edge states have been stabilized in out-of-plane applied magnetic field. Using the time-dependent Ginzburg–Landau equations we shed light on the dynamic response of such states to an external applied current. Three different regimes are obtained, namely, the superconducting (stationary), resistive (non-stationary) and normal regime, similarly to conventional s-wave superconductors. However, in the resistive regime and depending on the external current, we found that moving skyrmions and the edge state behave distinctly different from the conventional kinematic vortex, thereby providing new fingerprints for identification of p-wave superconductivity.
12. Remarks on twisted noncommutative quantum field theory
Energy Technology Data Exchange (ETDEWEB)
Zahn, J. [Hamburg Univ. (Germany). 2. Inst. fuer Theoretische Physik
2006-04-15
We review recent results on twisted noncommutative quantum field theory by embedding it into a general framework for the quantization of systems with a twisted symmetry. We discuss commutation relations in this setting and show that the twisted structure is so rigid that it is hard to derive any predictions, unless one gives up general principles of quantum theory. It is also shown that the twisted structure is not responsible for the presence or absence of UV/IR-mixing, as claimed in the literature. (Orig.)
13. DVCS amplitude with kinematical twist-3 terms
International Nuclear Information System (INIS)
2000-01-01
The authors compute the amplitude of deeply virtual Compton scattering (DVCS) using the calculus of QCD string operators in coordinate representation. To restore the electromagnetic gauge invariance (transversality) of the twist-2 amplitude they include the operators of twist-3 which appear as total derivatives of twist-2 operators. The results are equivalent to a Wandzura-Wilczek approximation for twist-3 skewed parton distributions. They find that this approximation gives a finite result for the amplitude of a longitudinally polarized virtual photon, while the amplitude for transverse polarization is divergent, i.e., factorization breaks down in this term
14. Skyrmion robustness in noncentrosymmetric magnets with axial symmetry: The role of anisotropy and tilted magnetic fields
Science.gov (United States)
Leonov, A. O.; Kézsmárki, I.
2017-12-01
We investigate the stability of Néel skyrmions against tilted magnetic fields in polar magnets with uniaxial anisotropy ranging from easy-plane to easy-axis type. We construct the corresponding phase diagrams and investigate the internal structure of skewed skyrmions with displaced cores. We find that moderate easy-plane anisotropy increases the stability range of Néel skyrmions for fields along the symmetry axis, while moderate easy-axis anisotropy enhances their robustness against tilted magnetic fields. We stress that the direction along which the skyrmion cores are shifted depends on the symmetry of the underlying crystal lattice. The cores of Néel skyrmions, realized in polar magnets with Cn v symmetry, are displaced either along or opposite to the off-axis (in-plane) component of the magnetic field depending on the rotation sense of the magnetization, dictated by the sign of the Dzyaloshinskii constant. The core shift of antiskyrmions, present in noncentrosymmetric magnets with D2 d symmetry, depends on the in-plane orientation of the magnetic field and can be parallel, antiparallel, or perpendicular to it. We argue that the role of anisotropy in magnets with axially symmetric crystal structure is different from that in cubic helimagnets. Our results can be applied to address recent experiments on polar magnets with C3 v symmetry, GaV4S8 and GaV4Se8 , and Mn1.4Pt0.9Pd0.1Sn with D2 d symmetry.
15. Device for measuring well twistings
Energy Technology Data Exchange (ETDEWEB)
Kostin, Yu S; Golubin, S V; Keller, V F; Merzheyevskiy, A B; Zdorov, V P
1982-01-01
The device for measuring the well twistings with the use of fluids (poured into a vessel and which leave an imprint on the walls), containing a housing and adapter, is distinguished by the fact that in order to improve the accuracy of measurement by obtaining a clear imprint, it is equipped with cylinder that is spring-loaded in relation to the adapter, forming a vessel for fluid with the adapter. The adapter is made of two parts, one of which is made of neutral metal in relation to the fluid, and the other, from active in relation to the same fluid.
16. Self-consistent mean field theory studies of the thermodynamics and quantum spin dynamics of magnetic Skyrmions.
Science.gov (United States)
Wieser, R
2017-05-04
A self-consistent mean field theory is introduced and used to investigate the thermodynamics and spin dynamics of an S = 1 quantum spin system with a magnetic Skyrmion. The temperature dependence of the Skyrmion profile as well as the phase diagram are calculated. In addition, the spin dynamics of a magnetic Skyrmion is described by solving the time dependent Schrödinger equation with additional damping term. The Skyrmion annihilation process driven by an electric field is used to compare the trajectories of the quantum mechanical simulation with a semi-classical description for the spin expectation values using a differential equation similar to the classical Landau-Lifshitz-Gilbert equation.
17. Observation of Various and Spontaneous Magnetic Skyrmionic Bubbles at Room Temperature in a Frustrated Kagome Magnet with Uniaxial Magnetic Anisotropy
KAUST Repository
Hou, Zhipeng; Ren, Weijun; Ding, Bei; Xu, Guizhou; Wang, Yue; Yang, Bing; Zhang, Qiang; Zhang, Ying; Liu, Enke; Xu, Feng; Wang, Wenhong; Wu, Guangheng; Zhang, Xixiang; Shen, Baogen; Zhang, Zhidong
2017-01-01
to various external stimuli acting as information carriers in spintronic devices. Here, the first observation of skyrmionic magnetic bubbles with variable topological spin textures formed at room temperature in a frustrated kagome Fe3 Sn2 magnet with uniaxial
18. Baby-Crying Acceptance
Science.gov (United States)
Martins, Tiago; de Magalhães, Sérgio Tenreiro
The baby's crying is his most important mean of communication. The crying monitoring performed by devices that have been developed doesn't ensure the complete safety of the child. It is necessary to join, to these technological resources, means of communicating the results to the responsible, which would involve the digital processing of information available from crying. The survey carried out, enabled to understand the level of adoption, in the continental territory of Portugal, of a technology that will be able to do such a digital processing. It was used the TAM as the theoretical referential. The statistical analysis showed that there is a good probability of acceptance of such a system.
19. JSW's baby cyclotron
International Nuclear Information System (INIS)
Toda, Y.; Kaneda, Y.; Satoh, Y.; Suzukawa, I.; Yamada, T.
1983-01-01
Designed by The Japan Steel Works, Ltd., specially for installation in a hospital's medical department and nuclear research laboratory, '' JSW BABY CYCLOTRON '' has been developed to produce short-lived radioisotopes such as 11C, 13N, 15O and 18F. JSW's Baby Cyclotron has some design features. 1) Fixed energy and four sector azimuthally varying field. 2) Compact figure desired for hospital's nuclear medical department 3) A bitter type magnet yoke shielding activity 4) Simple control and operation 5) Easy maintenance without skilled personnel. Type BC105 (P:10MeV, d:5MeV), BC107 (P:10MeV, d:7MeV), BC168 (P:16MeV, d:8MeV) and BC1710 (P:17MeV, d:10MeV) are available according to required amount of radioisotopes. In our radioisotope production test, yield and purity of 11C, 13N, 15O and 18F are usable to clinical diagnosis
20. Spontaneous nucleation and topological stabilization of skyrmions in magnetic nanodisks with the interfacial Dzyaloshinskii-Moriya interaction
Science.gov (United States)
Kolesnikov, A. G.; Samardak, A. S.; Stebliy, M. E.; Ognev, A. V.; Chebotkevich, L. A.; Sadovnikov, A. V.; Nikitov, S. A.; Kim, Yong Jin; Cha, In Ho; Kim, Young Keun
2017-05-01
One of the major societal challenges is reducing the power consumption of information technology (IT) devices and numerous data centers. Distinct from the current approaches based on switching of magnetic single-domain nanostructures or on movement of domain walls under high currents, an original magnetic skyrmion technology offers ultra-low power, fast, high-density, and scalable spintronic devices, including non-volatile random access memory. Using data-driven micromagnetic simulations, we demonstrate the possibility of spontaneous nucleation and stabilization of different skyrmionic states, such as skyrmions, merons, and meron-like configurations, in heavy metal/ferromagnetic nanodisks with the interfacial Dzyaloshinskii-Moriya interaction (iDMI) as a result of quasi-static magnetization reversal only. Since iDMI is not easily modulated in real systems, we show that skyrmion stabilization is easily achievable by manipulating magnetic anisotropy, saturation magnetization, and the diameters of nanodisks. The state diagrams, presented in terms of the topological charge, allow to explicitly distinguish the intermediate states between skyrmions and merons and can be used for developing a skyrmionic medium, which has been recently proposed to be a building block for future spin-orbitronic devices.
1. Azimuthal spin-wave excitations in magnetic nanodots over the soliton background: Vortex, Bloch, and Néel-like skyrmions
Science.gov (United States)
Mruczkiewicz, M.; Gruszecki, P.; Krawczyk, M.; Guslienko, K. Y.
2018-02-01
We study azimuthal spin-wave (SW) excitations in a circular ferromagnetic nanodot in different inhomogeneous, topologically nontrivial magnetization states, specifically, vortex, Bloch-type skyrmion, and Néel-type skyrmion states. A continuous transition between these states is realized by gradually changing the out-of-plane magnetic anisotropy and the Dzyaloshinskii-Moriya exchange interaction (DMI), and the corresponding SW spectra are calculated for each state. We observe the lifting of degeneracy of SW mode frequencies and a change in the systematics of frequency levels. The latter effect is induced by the geometric Berry phase, which occurs in SWs localized at the edge of the dot in the vortex state, and vanishes in the skyrmion states. Furthermore, channeling of edge-localized azimuthal SWs and a related large frequency splitting are observed in the skyrmion states. This is attributed to DMI-induced nonreciprocity, while the coupling of the breathing and gyrotropic modes is related to the skyrmion motion. Finally, we demonstrate efficient coupling of the dynamic magnetization to a uniform magnetic field in nanodots of noncircular symmetry in the skyrmion states.
2. Spontaneous nucleation and topological stabilization of skyrmions in magnetic nanodisks with the interfacial Dzyaloshinskii–Moriya interaction
Energy Technology Data Exchange (ETDEWEB)
Kolesnikov, A.G. [Laboratory of Thin Film Technologies, School of Natural Sciences, Far Eastern Federal University, Vladivostok 690950 (Russian Federation); Samardak, A.S., E-mail: samardak.as@dvfu.ru [Laboratory of Thin Film Technologies, School of Natural Sciences, Far Eastern Federal University, Vladivostok 690950 (Russian Federation); Stebliy, M.E.; Ognev, A.V.; Chebotkevich, L.A. [Laboratory of Thin Film Technologies, School of Natural Sciences, Far Eastern Federal University, Vladivostok 690950 (Russian Federation); Sadovnikov, A.V.; Nikitov, S.A. [Laboratory “Metamaterials,” Saratov State University, Saratov 410012 (Russian Federation); Kotel' nikov Institute of Radioengineering and Electronics, Russian Academy of Sciences, Moscow 125009 (Russian Federation); Kim, Yong Jin; Cha, In Ho [Department of Materials Science and Engineering, Korea University, Seoul 02841 (Korea, Republic of); Kim, Young Keun, E-mail: ykim97@korea.ac.kr [Department of Materials Science and Engineering, Korea University, Seoul 02841 (Korea, Republic of)
2017-05-01
One of the major societal challenges is reducing the power consumption of information technology (IT) devices and numerous data centers. Distinct from the current approaches based on switching of magnetic single-domain nanostructures or on movement of domain walls under high currents, an original magnetic skyrmion technology offers ultra-low power, fast, high-density, and scalable spintronic devices, including non-volatile random access memory. Using data-driven micromagnetic simulations, we demonstrate the possibility of spontaneous nucleation and stabilization of different skyrmionic states, such as skyrmions, merons, and meron-like configurations, in heavy metal/ferromagnetic nanodisks with the interfacial Dzyaloshinskii–Moriya interaction (iDMI) as a result of quasi-static magnetization reversal only. Since iDMI is not easily modulated in real systems, we show that skyrmion stabilization is easily achievable by manipulating magnetic anisotropy, saturation magnetization, and the diameters of nanodisks. The state diagrams, presented in terms of the topological charge, allow to explicitly distinguish the intermediate states between skyrmions and merons and can be used for developing a skyrmionic medium, which has been recently proposed to be a building block for future spin-orbitronic devices.
3. Twist-stretch profiles of DNA chains
Science.gov (United States)
Zoli, Marco
2017-06-01
Helical molecules change their twist number under the effect of a mechanical load. We study the twist-stretch relation for a set of short DNA molecules modeled by a mesoscopic Hamiltonian. Finite temperature path integral techniques are applied to generate a large ensemble of possible configurations for the base pairs of the sequence. The model also accounts for the bending and twisting fluctuations between adjacent base pairs along the molecules stack. Simulating a broad range of twisting conformation, we compute the helix structural parameters by averaging over the ensemble of base pairs configurations. The method selects, for any applied force, the average twist angle which minimizes the molecule’s free energy. It is found that the chains generally over-twist under an applied stretching and the over-twisting is physically associated to the contraction of the average helix diameter, i.e. to the damping of the base pair fluctuations. Instead, assuming that the maximum amplitude of the bending fluctuations may decrease against the external load, the DNA molecule first over-twists for weak applied forces and then untwists above a characteristic force value. Our results are discussed in relation to available experimental information albeit for kilo-base long molecules.
4. How Active Is Your Baby?
Science.gov (United States)
... range). As your baby develops, take advantage of every opportunity to help stimulate her mind and body. From the earliest weeks of life, walk around the house while holding and interacting with your baby and say aloud the names of the objects that the ...
5. Baby-MIND neutrino detector
Science.gov (United States)
Mefodiev, A. V.; Kudenko, Yu. G.; Mineev, O. V.; Khotjantsev, A. N.
2017-11-01
The main objective of the Baby-MIND detector (Magnetized Iron Neutrino Detector) is the study of muon charge identification efficiency for muon momenta from 0.3 to 5 GeV/ c. This paper presents the results of measurement of the Baby-MIND parameters.
6. Baby universes with induced gravity
International Nuclear Information System (INIS)
Gao Yihong; Gao Hongbo
1989-01-01
In this paper some quantum effects of baby universes with induced gravity are discussed. It is proved that the interactions between the baby-parent universes are non-local, and argue that the induced low-energy cosmological constant is zero. This argument does not depend on the detail of the induced potential
7. Colostrum: Your Baby's First Meal
Science.gov (United States)
... Our Sponsors Ages & Stages Ages & Stages Ages and Stages Prenatal Baby (0-12 mos.) Toddler 1-3yrs. Preschool 3-5yrs Grade School 5-12yrs. Teen 12- ... the Word Shop AAP Find a Pediatrician Ages & Stages Prenatal Baby Bathing & Skin ... Teen Young Adult Healthy Children > Ages & Stages > ...
8. The Baby Boomers' intergenerational relationships.
Science.gov (United States)
Fingerman, Karen L; Pillemer, Karl A; Silverstein, Merril; Suitor, J Jill
2012-04-01
As Baby Boomers enter late life, relationships with family members gain importance. This review article highlights two aspects of their intergenerational relationships: (a) caregiving for aging parents and (b) interactions with adult children in the context of changing marital dynamics. The researchers describe three studies: (a) the Within Family Differences Study (WFDS) of mothers aged 65-75 and their multiple grown children (primarily Baby Boomers) ongoing since 2001; (b) the Family Exchanges Study (FES) of Baby Boomers aged 42-60, their spouses, parents, and multiple grown children ongoing since 2008; and (c) the Longitudinal Study of Generations (LSoG) of 351 three-generation families started when the Baby Boomers were teenagers in 1971, with interviews every 3-5 years from 1985 to 2005. These studies show that the Baby Boomers in midlife navigate complex intergenerational patterns. The WFDS finds aging parents differentiate among Baby Boomer children in midlife, favoring some more than others. The FES shows that the Baby Boomers are typically more involved with their children than with their aging parents; Boomers' personal values, family members' needs, and personal rewards shape decisions about support. The LSoG documents how divorce and remarriage dampen intergenerational obligations in some families. Moreover, loosening cultural norms have weakened family bonds in general. Reviews of these studies provide insights into how the Baby Boomers may negotiate caregiving for aging parents as well as the likelihood of family care they will receive when their own health declines in the future.
9. Sirenomelia (Mermaid baby).
Science.gov (United States)
Akhtar, Jamshed; Shaikh, Muhammad Ali; Saleem, Nasir; Taqvi, Syed Raees; Jehan, Yaqoot; Batool, Tayyaba; Zameer, Naima; Mirza, Farhat
2005-11-01
Sirenomelia is a rare anomaly that rarely occurs as an isolated lesion. Several theories have been proposed regarding the etiopathogenesis. In this communication, we report a case of sirenomelia. Our patient was referred to hospital at the age of four hours. On examination, fusion of both lower limbs with hook shaped appendage, attached distally, absent genitalia and absent anal orifice was found. Spine was deficient in sacral region. Upper torso looked normal. Baby also had frothing from mouth. Abdomen was non-distended. Feeding tube no.10 was tried to pass through mouth, which got obstructed at the level of upper esophagus that suggested oesophageal atresia. The skeletogram revealed absence of pelvic bones, sacral agenesis, absent fibulae and fracture of both femora. The patient died at the age of 12 hours.
10. Quantisation of monotonic twist maps
International Nuclear Information System (INIS)
Boasman, P.A.; Smilansky, U.
1993-08-01
Using an approach suggested by Moser, classical Hamiltonians are generated that provide an interpolating flow to the stroboscopic motion of maps with a monotonic twist condition. The quantum properties of these Hamiltonians are then studied in analogy with recent work on the semiclassical quantization of systems based on Poincare surfaces of section. For the generalized standard map, the correspondence with the usual classical and quantum results is shown, and the advantages of the quantum Moser Hamiltonian demonstrated. The same approach is then applied to the free motion of a particle on a 2-torus, and to the circle billiard. A natural quantization condition based on the eigenphases of the unitary time--development operator is applied, leaving the exact eigenvalues of the torus, but only the semiclassical eigenvalues for the billiard; an explanation for this failure is proposed. It is also seen how iterating the classical map commutes with the quantization. (authors)
11. Ultrafast generation of skyrmionic defects with vortex beams: Printing laser profiles on magnets
Science.gov (United States)
Fujita, Hiroyuki; Sato, Masahiro
2017-02-01
Controlling electric and magnetic properties of matter by laser beams is actively explored in the broad region of condensed matter physics, including spintronics and magneto-optics. Here we theoretically propose an application of optical and electron vortex beams carrying intrinsic orbital angular momentum to chiral ferro- and antiferromagnets. We analyze the time evolution of spins in chiral magnets under irradiation of vortex beams by using the stochastic Landau-Lifshitz-Gilbert equation. We show that beam-driven nonuniform temperature leads to a class of ring-shaped magnetic defects, what we call skyrmion multiplex, as well as conventional skyrmions. We discuss the proper beam parameters and the optimal way of applying the beams for the creation of these topological defects. Our findings provide an ultrafast scheme of generating topological magnetic defects in a way applicable to both metallic and insulating chiral (anti-) ferromagnets.
12. Four-point functions with a twist
Energy Technology Data Exchange (ETDEWEB)
Bargheer, Till [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany). Theory Group
2017-01-15
We study the OPE of correlation functions of local operators in planar N=4 super Yang-Mills theory. The considered operators have an explicit spacetime dependence that is defined by twisting the translation generators with certain R-symmetry generators. We restrict to operators that carry a small number of excitations above the twisted BMN vacuum. The OPE limit of the four-point correlator is dominated by internal states with few magnons on top of the vacuum. The twisting directly couples all spacetime dependence of the correlator to these magnons. We analyze the OPE in detail, and single out the extremal states that have to cancel all double-trace contributions.
13. Euclidean supersymmetry, twisting and topological sigma models
International Nuclear Information System (INIS)
Hull, C.M.; Lindstroem, U.; Santos, L. Melo dos; Zabzine, M.; Unge, R. von
2008-01-01
We discuss two dimensional N-extended supersymmetry in Euclidean signature and its R-symmetry. For N = 2, the R-symmetry is SO(2) x SO(1, 1), so that only an A-twist is possible. To formulate a B-twist, or to construct Euclidean N = 2 models with H-flux so that the target geometry is generalised Kahler, it is necessary to work with a complexification of the sigma models. These issues are related to the obstructions to the existence of non-trivial twisted chiral superfields in Euclidean superspace.
14. Baby universes, fine tuning problems
International Nuclear Information System (INIS)
Nielsen, H.B.; Ninomiya, Masao.
1988-12-01
We review the recently popular 'theory of baby universes' put forward by Banks, Coleman and Hawking. We then derive the strong CP breaking coefficient θ-bar to be very small, in a similar manner to the derivation of the cosmological constant being zero. A solution for an old controversy concerning the entropy creation in black holes is also discussed. We finally confront the baby universe theory with random dynamics. We conclude that the theory of baby universes is so successful that the essential features are likely true and might have to go into a right theory even if with some troubles at first. (author)
15. Recognition of a Baby's Emotional Cry Towards Robotics Baby Caregiver
OpenAIRE
Yamamoto, Shota; Yoshitomi, Yasunari; Tabuse, Masayoshi; Kushida, Kou; Asada, Taro
2013-01-01
We developed a method for pattern recognition of baby's emotions (discomfortable, hungry, or sleepy) expressed in the baby's cries. A 32-dimensional fast Fourier transform is performed for sound form clips, detected by our reported method and used as training data. The power of the sound form judged as a silent region is subtracted from each power of the frequency element. The power of each frequency element after the subtraction is treated as one of the elements of the feature vector. We per...
16. Theory of high-resolution tunneling spin transport on a magnetic skyrmion
OpenAIRE
Palotás, Krisztián; Rózsa, Levente; Szunyogh, László
2018-01-01
Tunneling spin transport characteristics of a magnetic skyrmion are described theoretically in magnetic scanning tunneling microscopy (STM). The spin-polarized charge current in STM (SP-STM) and tunneling spin transport vector quantities, the longitudinal spin current and the spin transfer torque are calculated in high spatial resolution within the same theoretical framework. A connection between the conventional charge current SP-STM image contrasts and the magnitudes of the spin transport v...
17. Rourke Baby Record 2014
Science.gov (United States)
Riverin, Bruno; Li, Patricia; Rourke, Leslie; Leduc, Denis; Rourke, James
2015-01-01
18. Universal current-velocity relation of skyrmion motion in chiral magnets
Science.gov (United States)
Iwasaki, Junichi; Mochizuki, Masahito; Nagaosa, Naoto
2013-03-01
Current-driven motion of the magnetic domain wall requires large critical current density jc ~109 -1012 A/m2, at which the joule heating is a serious problem. The skyrmions recently discovered in chiral magnets, on the other hand, have much smaller critical current of jc ~105 -106 A/m2. We present a numerical simulation of the Landau-Lifshitz-Gilbert equation, which reveals a remarkably robust and universal current-velocity relation of the slyrmion motion driven by the spin transfer torque unaffected by either impurities or nonadiabatic effect in sharp contrast to the case of domain wall or spin helix (HL). Simulation results are analyzed using a theory based on Thiele's equation, and it is concluded that this surprising behavior is due to the Magnus force and flexible shape-deformation of individual skyrmions and skyrmion crystal (SkX), which enable them to avoid pinning centers and then weaken the net pinning force. Dynamical deformation of SkX leads to the fluctuation of Bragg peak with large amplitude, which can be detected by the recent neutron-scattering experiment.
19. Health Issues of Premature Babies
Science.gov (United States)
... they leave the hospital for home. Retinopathy of Prematurity (ROP) What It Is: ROP is an eye ... sometimes seen in preterm babies include anemia of prematurity (a low red blood cell count) and heart ...
20. Collodion Baby - a Case Report
Directory of Open Access Journals (Sweden)
Stojanović Vesna
2014-12-01
Full Text Available Colloidon baby describes a highly characteristic clinical entity in newborns encased in a yellowish translucent membrane resembling collodion. In most cases the condition either precedes the development of one of a variety of ichthyoses, the commonest of which are lamellar ichthyosis and non-bullous ichthyosiform erythroderma, or occasionally represents an initial phase of other ichthyoses such as ichthyosis vulgaris. In at least 10% of all cases of collodion baby, the condition is followed by a mild ichthyosis of lamellar type, so mild as to be considered more or less normal, so-called self-healing collodion baby or ‘lamellar ichthyosis of the newborn’. In this report we present a rare case of collodion baby in whom, after collodion membrane peeled-off, the skin retained normal appearance.
1. On the twist-2 and twist-3 contributions to the spin-dependent electroweak structure functions
International Nuclear Information System (INIS)
Bluemlein, J.; Kochelev, N.
1997-01-01
The twist-2 and twist-3 contributions of the polarized deep-inelastic structure functions are calculated both for neutral and charged current interactions using the operator product expansion in lowest order in QCD. The relations between the different structure functions are determined. New integral relations are derived between the twist-2 contributions of the structure functions g 3 (x,Q 2 ) and g 5 (x,Q 2 ) and between combinations of the twist-3 contributions to the structure functions g 2 (x,Q 2 ) and g 3 (x,Q 2 ). The sum rules for polarized deep-inelastic scattering are discussed in detail. (orig.)
2. Twisted Vector Bundles on Pointed Nodal Curves
Abstract. Motivated by the quest for a good compactification of the moduli space of -bundles on a nodal curve we establish a striking relationship between Abramovich's and Vistoli's twisted bundles and Gieseker vector bundles.
3. The LHC babies
CERN Multimedia
Laëtitia Pedroso
2011-01-01
With the machine restart and first collisions at 3.5 TeV, 2009 and 2010 were two action-packed years at the LHC. The events were a real media success, but one important result that remained well hidden was the ten births in the LHC team over the same period. The mothers – engineers, cryogenics experts and administrative assistants working for the LHC – confirm that it is possible to maintain a reasonable work-life balance. Two of them tell us more… Verena Kain (left) and Reyes Alemany (right) in the CERN Control Centre. With the LHC running around the clock, LHC operations engineers have high-pressure jobs with unsociable working hours. These past two years, which will undoubtedly go down in the annals of CERN history, the LHC team had their work cut out, but despite their high-octane professional lives, several female members of the team took up no less of a challenge in their private lives, creating a mini-baby-boom by which the LHC start-up will also be remembe...
4. The Baby Boomers’ Intergenerational Relationships
Science.gov (United States)
Fingerman, Karen L.; Pillemer, Karl A.; Silverstein, Merril; Suitor, J. Jill
2012-01-01
Purpose: As Baby Boomers enter late life, relationships with family members gain importance. This review article highlights two aspects of their intergenerational relationships: (a) caregiving for aging parents and (b) interactions with adult children in the context of changing marital dynamics. Design and Methods: The researchers describe three studies: (a) the Within Family Differences Study (WFDS) of mothers aged 65–75 and their multiple grown children (primarily Baby Boomers) ongoing since 2001; (b) the Family Exchanges Study (FES) of Baby Boomers aged 42–60, their spouses, parents, and multiple grown children ongoing since 2008; and (c) the Longitudinal Study of Generations (LSoG) of 351 three-generation families started when the Baby Boomers were teenagers in 1971, with interviews every 3–5 years from 1985 to 2005. Results: These studies show that the Baby Boomers in midlife navigate complex intergenerational patterns. The WFDS finds aging parents differentiate among Baby Boomer children in midlife, favoring some more than others. The FES shows that the Baby Boomers are typically more involved with their children than with their aging parents; Boomers’ personal values, family members’ needs, and personal rewards shape decisions about support. The LSoG documents how divorce and remarriage dampen intergenerational obligations in some families. Moreover, loosening cultural norms have weakened family bonds in general. Implications: Reviews of these studies provide insights into how the Baby Boomers may negotiate caregiving for aging parents as well as the likelihood of family care they will receive when their own health declines in the future. PMID:22250130
5. Twisted covariant noncommutative self-dual gravity
International Nuclear Information System (INIS)
Estrada-Jimenez, S.; Garcia-Compean, H.; Obregon, O.; Ramirez, C.
2008-01-01
A twisted covariant formulation of noncommutative self-dual gravity is presented. The formulation for constructing twisted noncommutative Yang-Mills theories is used. It is shown that the noncommutative torsion is solved at any order of the θ expansion in terms of the tetrad and some extra fields of the theory. In the process the first order expansion in θ for the Plebanski action is explicitly obtained.
6. Nonlinear physics of twisted magnetic field lines
International Nuclear Information System (INIS)
Yoshida, Zensho
1998-01-01
Twisted magnetic field lines appear commonly in many different plasma systems, such as magnetic ropes created through interactions between the magnetosphere and the solar wind, magnetic clouds in the solar wind, solar corona, galactic jets, accretion discs, as well as fusion plasma devices. In this paper, we study the topological characterization of twisted magnetic fields, nonlinear effect induced by the Lorentz back reaction, length-scale bounds, and statistical distributions. (author)
7. OAM mode converter in twisted fibers
DEFF Research Database (Denmark)
Usuga Castaneda, Mario A.; Beltran-Mejia, Felipe; Cordeiro, Cristiano
2014-01-01
We analyze the case of an OAM mode converter based on a twisted fiber, through finite element simulations where we exploit an equivalence between geometric and material transformations. The obtained converter has potential applications in MDM. © 2014 OSA.......We analyze the case of an OAM mode converter based on a twisted fiber, through finite element simulations where we exploit an equivalence between geometric and material transformations. The obtained converter has potential applications in MDM. © 2014 OSA....
8. Further Generalisations of Twisted Gabidulin Codes
DEFF Research Database (Denmark)
Puchinger, Sven; Rosenkilde, Johan Sebastian Heesemann; Sheekey, John
2017-01-01
We present a new family of maximum rank distance (MRD) codes. The new class contains codes that are neither equivalent to a generalised Gabidulin nor to a twisted Gabidulin code, the only two known general constructions of linear MRD codes.......We present a new family of maximum rank distance (MRD) codes. The new class contains codes that are neither equivalent to a generalised Gabidulin nor to a twisted Gabidulin code, the only two known general constructions of linear MRD codes....
9. Nonlinear Magnus-induced dynamics and Shapiro spikes for ac and dc driven skyrmions on periodic quasi-one-dimensional substrates
Science.gov (United States)
Reichhardt, Charles; Reichhardt, Cynthia J. Olson
We numerically examine skyrmions interacting with a periodic quasi-one-dimensional substrate. When we drive the skyrmions perpendicular to the substrate periodicity direction, a rich variety of nonlinear Magnus-induced effects arise, in contrast to an overdamped system that shows only a linear velocity-force curve for this geometry. The skyrmion velocity-force curve is strongly nonlinear and we observe a Magnus-induced speed-up effect when the pinning causes the Magnus velocity response to align with the dissipative response. At higher applied drives these components decouple, resulting in strong negative differential conductivity. For skyrmions under combined ac and dc driving, we find a new class of phase locking phenomena in which the velocity-force curves contain a series of what we call Shapiro spikes, distinct from the Shapiro steps observed in overdamped systems. There are also regimes in which the skyrmion moves in the direction opposite to the applied dc drive to give negative mobility.
10. Observation of Various and Spontaneous Magnetic Skyrmionic Bubbles at Room Temperature in a Frustrated Kagome Magnet with Uniaxial Magnetic Anisotropy
KAUST Repository
Hou, Zhipeng
2017-06-07
The quest for materials hosting topologically protected skyrmionic spin textures continues to be fueled by the promise of novel devices. Although many materials have demonstrated the existence of such spin textures, major challenges remain to be addressed before devices based on magnetic skyrmions can be realized. For example, being able to create and manipulate skyrmionic spin textures at room temperature is of great importance for further technological applications because they can adapt to various external stimuli acting as information carriers in spintronic devices. Here, the first observation of skyrmionic magnetic bubbles with variable topological spin textures formed at room temperature in a frustrated kagome Fe3 Sn2 magnet with uniaxial magnetic anisotropy is reported. The magnetization dynamics are investigated using in situ Lorentz transmission electron microscopy, revealing that the transformation between different magnetic bubbles and domains is via the motion of Bloch lines driven by an applied external magnetic field. These results demonstrate that Fe3 Sn2 facilitates a unique magnetic control of topological spin textures at room temperature, making it a promising candidate for further skyrmion-based spintronic devices.
11. Electrical-field-induced magnetic Skyrmion ground state in a two-dimensional chromium tri-iodide ferromagnetic monolayer
Science.gov (United States)
Liu, Jie; Shi, Mengchao; Mo, Pinghui; Lu, Jiwu
2018-05-01
Using fully first-principles non-collinear self-consistent field density functional theory (DFT) calculations with relativistic spin-orbital coupling effects, we show that, by applying an out-of-plane electrical field on a free-standing two-dimensional chromium tri-iodide (CrI3) ferromagnetic monolayer, the Néel-type magnetic Skyrmion spin configurations become more energetically-favorable than the ferromagnetic spin configurations. It is revealed that the topologically-protected Skyrmion ground state is caused by the breaking of inversion symmetry, which induces the non-trivial Dzyaloshinskii-Moriya interaction (DMI) and the energetically-favorable spin-canting configuration. Combining the ferromagnetic and the magnetic Skyrmion ground states, it is shown that 4-level data can be stored in a single monolayer-based spintronic device, which is of practical interests to realize the next-generation energy-efficient quaternary logic devices and multilevel memory devices.
12. Soft tissue twisting injuries of the knee
International Nuclear Information System (INIS)
Magee, T.; Shapiro, M.
2001-01-01
Twisting injuries occur as a result of differential motion of different tissue types in injuries with some rotational force. These injuries are well described in brain injuries but, to our knowledge, have not been described in the musculoskeletal literature. We correlated the clinical examination and MR findings of 20 patients with twisting injuries of the soft tissues around the knee. Design and patients: We prospectively followed the clinical courses of 20 patients with knee injuries who had clinical histories and MR findings to suggest twisting injuries of the subcutaneous tissues. Patients with associated internal derangement of the knee (i.e., meniscal tears, ligamentous or bone injuries) were excluded from this study. MR findings to suggest twisting injuries included linear areas of abnormal dark signal on T1-weighted sequences and abnormal bright signal on T2-weighted or short tau inversion recovery (STIR) sequences and/or signal to suggest hemorrhage within the subcutaneous tissues. These MR criteria were adapted from those established for indirect musculotendinous junction injuries. Results: All 20 patients presented with considerable pain that suggested internal derangement on physical examination by the referring orthopedic surgeons. All presented with injuries associated with rotational force. The patients were placed on a course of protected weight-bearing of the affected extremity for 4 weeks. All patients had pain relief by clinical examination after this period of protected weight-bearing. Twisting injuries of the soft tissues can result in considerable pain that can be confused with internal derangement of the knee on physical examination. Soft tissue twisting injuries need to be recognized on MR examinations as they may be the cause of the patient's pain despite no MR evidence of internal derangement of the knee. The demonstration of soft tissue twisting injuries in a patient with severe knee pain but no documented internal derangement on MR
13. Quantum entanglement of baby universes
International Nuclear Information System (INIS)
Aganagic, Mina; Okuda, Takuya; Ooguri, Hirosi
2007-01-01
We study quantum entanglements of baby universes which appear in non-perturbative corrections to the OSV formula for the entropy of extremal black holes in type IIA string theory compactified on the local Calabi-Yau manifold defined as a rank 2 vector bundle over an arbitrary genus G Riemann surface. This generalizes the result for G=1 in hep-th/0504221. Non-perturbative terms can be organized into a sum over contributions from baby universes, and the total wave-function is their coherent superposition in the third quantized Hilbert space. We find that half of the universes preserve one set of supercharges while the other half preserve a different set, making the total universe stable but non-BPS. The parent universe generates baby universes by brane/anti-brane pair creation, and baby universes are correlated by conservation of non-normalizable D-brane charges under the process. There are no other source of entanglement of baby universes, and all possible states are superposed with the equal weight
14. Quantum entanglement of baby universes
International Nuclear Information System (INIS)
Essman, Eric P.; Aganagic, Mina; Okuda, Takuya; Ooguri, Hirosi
2006-01-01
We study quantum entanglements of baby universes which appear in non-perturbative corrections to the OSV formula for the entropy of extremal black holes in type IIA string theory compactified on the local Calabi-Yau manifold defined as a rank 2 vector bundle over an arbitrary genus G Riemann surface. This generalizes the result for G=1 in hep-th/0504221. Non-perturbative terms can be organized into a sum over contributions from baby universes, and the total wave-function is their coherent superposition in the third quantized Hilbert space. We find that half of the universes preserve one set of supercharges while the other half preserve a different set, making the total universe stable but non-BPS. The parent universe generates baby universes by brane/anti-brane pair creation, and baby universes are correlated by conservation of non-normalizable D-brane charges under the process. There are no other source of entanglement of baby universes, and all possible states are superposed with the equal weight
15. Baby Solar System
Science.gov (United States)
2012-01-01
What did our solar system look like in its infancy,...... when the planets were forming? We cannot travel back in time to take an image of the early solar system, but in principle we can have the next best thing: images of infant planetary systems around Sun-like stars with ages of 1 to 5 million years, the time we think it took for the giant planets to form. Infant exoplanetary systems are critically important because they can help us understand how our solar system fits within the context of planet formation in general. More than 80% of stars are born with gas- and dust-rich disks, and thus have the potential to form planets. Through many methods we have identified more than 760 planetary systems around middle-aged stars like the Sun, but many of these have architectures that look nothing like our solar system. Young planetary systems are important missing links between various endpoints and may help us understand how and when these differences emerge. Well-known star-forming regions in Taurus, Scorpius. and Orion contain stars that could have infant planetary systems. But these stars are much more distant than our nearest neighbors such as Alpha Centauri or Sirius, making it extremely challenging to produce clear images of systems that can reveal signs of recent planet formation, let alone reveal the planets themselves. Recently, a star with the unassuming name LkCa 15 may have given us our first detailed "baby picture" of a young planetary system similar to our solar system. Located about 450 light-years away in the Taurus starforming region. LkCa 15 has a mass comparable to the Sun (0.97 solar mass) and an age of l to 5 million years, comparable to the time at which Saturn and perhaps Jupiter formed. The star is surrounded by a gas-rich disk similar in structure to the one in our solar system from which the planets formed. With new technologies and observing strategies, we have confirmed suspicions that LkCa 15's disk harbors a young planetary system.
16. Stray field signatures of Néel textured skyrmions in Ir/Fe/Co/Pt multilayer films
Science.gov (United States)
Yagil, A.; Almoalem, A.; Soumyanarayanan, Anjan; Tan, Anthony K. C.; Raju, M.; Panagopoulos, C.; Auslaender, O. M.
2018-05-01
Skyrmions are nanoscale spin configurations with topological properties that hold great promise for spintronic devices. Here, we establish their Néel texture, helicity, and size in Ir/Fe/Co/Pt multilayer films by constructing a multipole expansion to model their stray field signatures and applying it to magnetic force microscopy images. Furthermore, the demonstrated sensitivity to inhomogeneity in skyrmion properties, coupled with a unique capability to estimate the pinning force governing dynamics, portend broad applicability in the burgeoning field of topological spin textures.
17. Twisted electron-acoustic waves in plasmas
International Nuclear Information System (INIS)
Aman-ur-Rehman; Ali, S.; Khan, S. A.; Shahzad, K.
2016-01-01
In the paraxial limit, a twisted electron-acoustic (EA) wave is studied in a collisionless unmagnetized plasma, whose constituents are the dynamical cold electrons and Boltzmannian hot electrons in the background of static positive ions. The analytical and numerical solutions of the plasma kinetic equation suggest that EA waves with finite amount of orbital angular momentum exhibit a twist in its behavior. The twisted wave particle resonance is also taken into consideration that has been appeared through the effective wave number q_e_f_f accounting for Laguerre-Gaussian mode profiles attributed to helical phase structures. Consequently, the dispersion relation and the damping rate of the EA waves are significantly modified with the twisted parameter η, and for η → ∞, the results coincide with the straight propagating plane EA waves. Numerically, new features of twisted EA waves are identified by considering various regimes of wavelength and the results might be useful for transport and trapping of plasma particles in a two-electron component plasma.
18. Designer babies--why not?
Science.gov (United States)
Evans, M
2001-02-01
Though many objections can be levelled against the idea of the practice of genetic intervention to produce 'designer babies', upon examination they are shown to hinge on features which concern parental intentions towards their children, rather than features specific to the means involved. These intentions may be pursued by a variety of social practices which may, though need not, involve a measure of 'traditional' genetic selection (i.e. in terms of the identity and characteristics of the reproducing partners). This paper reviews a number of these objections and, by parity of reasoning, rejects their claim to count specifically or decisively against genetic intervention in pursuit of 'designer babies'. Rejecting these objections does not lead to the endorsement of 'designing babies, but it shows that any unease must be grounded elsewhere and defended by other arguments.
19. 'Dodo' and 'Baby Bear' Trenches
Science.gov (United States)
2008-01-01
NASA's Phoenix Mars Lander's Surface Stereo Imager took this image on Sol 11 (June 5, 2008), the eleventh day after landing. It shows the trenches dug by Phoenix's Robotic Arm. The trench on the left is informally called 'Dodo' and was dug as a test. The trench on the right is informally called 'Baby Bear.' The sample dug from Baby Bear will be delivered to the Phoenix's Thermal and Evolved-Gas Analyzer, or TEGA. The Baby Bear trench is 9 centimeters (3.1 inches) wide and 4 centimeters (1.6 inches) deep. The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.
20. Baby MIND Experiment Construction Status
Energy Technology Data Exchange (ETDEWEB)
Antonova, M.; et al.
2017-04-28
Baby MIND is a magnetized iron neutrino detector, with novel design features, and is planned to serve as a downstream magnetized muon spectrometer for the WAGASCI experiment on the T2K neutrino beam line in Japan. One of the main goals of this experiment is to reduce systematic uncertainties relevant to CP-violation searches, by measuring the neutrino contamination in the anti-neutrino beam mode of T2K. Baby MIND is currently being constructed at CERN, and is planned to be operational in Japan in October 2017.
1. 29 BABY DUMPING AND EVOLVING BABY FACTORIES IN NIGERIA
African Journals Online (AJOL)
room for a conducive environment for child rights and social protection. ... new dimensions to include the worst of all forms of human trafficking issues ... of strict penalties for offenders in the bid to give every child born the benefit of ..... vein, the study conducted by Onuoha (2014) listed the causes of baby factory incidences to.
2. Electrically Controllable Magnetism in Twisted Bilayer Graphene.
Science.gov (United States)
Gonzalez-Arraga, Luis A; Lado, J L; Guinea, Francisco; San-Jose, Pablo
2017-09-08
Twisted graphene bilayers develop highly localized states around AA-stacked regions for small twist angles. We show that interaction effects may induce either an antiferromagnetic or a ferromagnetic (FM) polarization of said regions, depending on the electrical bias between layers. Remarkably, FM-polarized AA regions under bias develop spiral magnetic ordering, with a relative 120° misalignment between neighboring regions due to a frustrated antiferromagnetic exchange. This remarkable spiral magnetism emerges naturally without the need of spin-orbit coupling, and competes with the more conventional lattice-antiferromagnetic instability, which interestingly develops at smaller bias under weaker interactions than in monolayer graphene, due to Fermi velocity suppression. This rich and electrically controllable magnetism could turn twisted bilayer graphene into an ideal system to study frustrated magnetism in two dimensions.
3. Gauged multisoliton baby Skyrme model
Science.gov (United States)
Samoilenka, A.; Shnir, Ya.
2016-03-01
We present a study of U (1 ) gauged modification of the 2 +1 -dimensional planar Skyrme model with a particular choice of the symmetry breaking potential term which combines a short-range repulsion and a long-range attraction. In the absence of the gauge interaction, the multisolitons of the model are aloof, as they consist of the individual constituents which are well separated. A peculiar feature of the model is that there are usually several different stable static multisoliton solutions of rather similar energy in a topological sector of given degree. We investigate the pattern of the solutions and find new previously unknown local minima. It is shown that coupling of the aloof planar multi-Skyrmions to the magnetic field strongly affects the pattern of interaction between the constituents. We analyze the dependency of the structure of the solutions, their energies, and magnetic fluxes on the strength of the gauge coupling. It is found that, generically, in the strong coupling limit, the coupling to the gauge field results in effective recovery of the rotational invariance of the configuration.
4. Fetal Echocardiography/Your Unborn Baby's Heart
Science.gov (United States)
... Artery Disease Venous Thromboembolism Aortic Aneurysm More Fetal Echocardiography / Your Unborn Baby's Heart Updated:Oct 6,2016 ... Your Risk • Symptoms & Diagnosis Introduction Common Tests Fetal Echocardiography/Your Unborn Baby's Heart - Fetal Echocardiogram Test - Detection ...
5. Feeding patterns and diet -- babies and infants
Science.gov (United States)
... child's state of development Can help prevent childhood obesity Recommendations During the first 6 months of life, your baby needs only breast milk or formula for proper nutrition. Your baby will ...
6. Crying Baby? How to Keep Your Cool
Science.gov (United States)
... fatal. If you're having trouble managing your emotions or dealing with parenthood, seek help. Your baby's ... infant-and-toddler-health/in-depth/crying-baby/art-20046995 . Mayo Clinic Footer Legal Conditions and Terms ...
7. Higher-twist correlations in polarized hadrons
International Nuclear Information System (INIS)
Tangerman, R.D.
1996-01-01
In this thesis we studied the response of polarized hadrons to several high-energy probes, working in the framework of the field theoretic model. Emphasis is laid upon higher-twist effects such as quark transverse momentum. The inclusive DIS process is very well suited to study QCD. From general principles we were able to derive four positivity constraints on the structure functions without invoking the helicity formalism. The on-shell quark model is used to illustrate these constraints. Subseqeuently, we concentrated on the higher-twist structure function g 2 (x,Q 2 ). (orig./HSI)
8. Factorising the 3D topologically twisted index
Science.gov (United States)
Cabo-Bizet, Alejandro
2017-04-01
We explore the path integration — upon the contour of hermitian (non-auxliary) field configurations — of topologically twisted N=2 Chern-Simons-matter theory (TTCSM) on {S}_2 times a segment. In this way, we obtain the formula for the 3D topologically twisted index, first as a convolution of TTCSM on {S}_2 times halves of {S}_1 , second as TTCSM on {S}_2 times {S}_1 — with a puncture, — and third as TTCSM on {S}_2× {S}_1 . In contradistinction to the first two cases, in the third case, the vector multiplet auxiliary field D is constrained to be anti-hermitian.
9. Anisotropic magnetocrystalline coupling of the skyrmion lattice in MnSi
Science.gov (United States)
Luo, Yongkang; Lin, Shi-Zeng; Fobes, D. M.; Liu, Zhiqi; Bauer, E. D.; Betts, J. B.; Migliori, A.; Thompson, J. D.; Janoschek, M.; Maiorov, B.
2018-03-01
We investigate the anisotropic nature of magnetocrystalline coupling between the crystallographic and skyrmion crystal (SKX) lattices in the chiral magnet MnSi by magnetic field-angle resolved resonant ultrasound spectroscopy. Abrupt changes are observed in the elastic moduli and attenuation when the magnetic field is parallel to the [011] crystallographic direction. These observations are interpreted in a phenomenological Ginzburg-Landau theory that identifies switching of the SKX orientation to be the result of an anisotropic magnetocrystalline coupling potential. Our paper sheds new light on the nature of magnetocrystalline coupling potential relevant to future spintronic applications.
10. Nucleon-delta mass difference in the chiral bag plus skyrmion hybrid model
International Nuclear Information System (INIS)
Kusaka, K.; Toki, H.
1988-01-01
We study the nucleon-delta isobar mass difference in the chiral bag plus skyrmion hybrid model (CSH). While in the Skyrme model the collective rotation solely provides the mass difference, in the CSH model the one-gluon exchange process also contributes in addition to the collective rotation due to the broken symmetry restoration. We study the one-gluon exchange contribution using the collective coordinate projection method. We find that the one-gluon exchange energy tends to compensate for the decreasing tendency of the rotational energy in the large bag region. (orig.)
11. A higher twist correction to heavy quark production
International Nuclear Information System (INIS)
Brodsky, S.J.; Gunion, J.F.; Soper, D.E.
1987-06-01
The leading twist prediction for heavy quark production and a model for a higher twist correction that may be important for charm production was discussed. The correction arises from the interaction of the charm quark with spectator quarks
12. The Baby Boomers' Intergenerational Relationships
Science.gov (United States)
Fingerman, Karen L.; Pillemer, Karl A.; Silverstein, Merril; Suitor, J. Jill
2012-01-01
Purpose: As Baby Boomers enter late life, relationships with family members gain importance. This review article highlights two aspects of their intergenerational relationships: (a) caregiving for aging parents and (b) interactions with adult children in the context of changing marital dynamics. Design and Methods: The researchers describe three…
13. Best-feeding the baby
African Journals Online (AJOL)
Enrique
Best-feeding the baby. Human infants should be fed their own mothers' breast- milk. Where this is unavailable, replacement feeding becomes necessary. Through the ages and right up to the present, human milk has been supplied by other lactating women within or from outside the family. Donated breast-milk has been ...
14. Babies, Toddlers and the Media.
Science.gov (United States)
Fenichel, Emily, Ed.
2001-01-01
"Zero to Three" is a single-focus bulletin of the National Center for Infants, Toddlers, and Families providing insight from multiple disciplines on the development of infants, toddlers, and their families. Noting that America's babies and toddlers live in a world full of television sets, VCRs, computers, videogames, and interactive…
15. Preparing Your Family for a New Baby
Science.gov (United States)
... Shop AAP Find a Pediatrician Ages & Stages Prenatal Decisions to Make Delivery and Beyond Baby Toddler Preschool Gradeschool Teen ... preschooler in planning for the baby . This will make him less jealous. ... you get them ready for the new baby. Buy your child (boy or girl) a doll so ...
16. Twist operators in N=4 beta-deformed theory
NARCIS (Netherlands)
de Leeuw, M.; Łukowski, T.
2010-01-01
In this paper we derive both the leading order finite size corrections for twist-2 and twist-3 operators and the next-to-leading order finite-size correction for twist-2 operators in beta-deformed SYM theory. The obtained results respect the principle of maximum transcendentality as well as
17. Twisted Frobenius Identities from Vertex Operator Superalgebras
Directory of Open Access Journals (Sweden)
Alexander Zuevsky
2017-01-01
Full Text Available In consideration of the continuous orbifold partition function and a generating function for all n-point correlation functions for the rank two free fermion vertex operator superalgebra on the self-sewing torus, we introduce the twisted version of Frobenius identity.
18. Magnetization Modeling of Twisted Superconducting Filaments
CERN Document Server
Satiramatekul, T; Devred, Arnaud; Leroy, Daniel
2007-01-01
This paper presents a new Finite Element numerical method to analyze the coupling between twisted filaments in a superconducting multifilament composite wire. To avoid the large number of elements required by a 3D code, the proposed method makes use of the energy balance principle in a 2D code. The relationship between superconductor critical current density and local magnetic flux density is implemented in the program for the Bean and modified Kim models. The modeled wire is made up of six filaments twisted together and embedded in a lowresistivity matrix. Computations of magnetization cycle and of the electric field pattern have been performed for various twist pitch values in the case of a pure copper matrix. The results confirm that the maximum magnetization depends on the matrix conductivity, the superconductor critical current density, the applied field frequency, and the filament twist pitch. The simulations also lead to a practical criterion for wire design that can be used to assess whether or not th...
19. Hilbert's Grand Hotel with a series twist
Science.gov (United States)
Wijeratne, Chanakya; Mamolo, Ami; Zazkis, Rina
2014-08-01
This paper presents a new twist on a familiar paradox, linking seemingly disparate ideas under one roof. Hilbert's Grand Hotel, a paradox which addresses infinite set comparisons is adapted and extended to incorporate ideas from calculus - namely infinite series. We present and resolve several variations, and invite the reader to explore his or her own variations.
20. On the Compton Twist-3 Asymmetries
International Nuclear Information System (INIS)
Korotkiyan, V.M.; Teryaev, O.V.
1994-01-01
The 'fermionic poles' contribution to the twist-3 single asymmetry in the gluon Compton process is calculated. The 'gluonic poles' existence seems to contradict the density matrix positivity. Qualitative predictions for the direct photon and jets asymmetries are presented. 13 refs., 2 figs
1. Generalized Weyl modules for twisted current algebras
Science.gov (United States)
Makedonskyi, I. A.; Feigin, E. B.
2017-08-01
We introduce the notion of generalized Weyl modules for twisted current algebras. We study their representation-theoretic and combinatorial properties and also their connection with nonsymmetric Macdonald polynomials. As an application, we compute the dimension of the classical Weyl modules in the remaining unknown case.
2. Hardy Inequalities in Globally Twisted Waveguides
Czech Academy of Sciences Publication Activity Database
Briet, Ph.; Hammedi, H.; Krejčiřík, David
2015-01-01
Roč. 105, č. 7 (2015), s. 939-958 ISSN 0377-9017 R&D Projects: GA ČR(CZ) GA14-06818S Institutional support: RVO:61389005 Keywords : quantum waveguides * twisted tubes * Dirichlet Laplacian * Hardy inequality Subject RIV: BE - Theoretical Physics Impact factor: 1.517, year: 2015
3. Morphing wing structure with controllable twist based on adaptive bending-twist coupling
Science.gov (United States)
Raither, Wolfram; Heymanns, Matthias; Bergamini, Andrea; Ermanni, Paolo
2013-06-01
A novel semi-passive morphing airfoil concept based on variable bending-twist coupling induced by adaptive shear center location and torsional stiffness is presented. Numerical parametric studies and upscaling show that the concept relying on smart materials permits effective twist control while offering the potential of being lightweight and energy efficient. By means of an experimental characterization of an adaptive beam and a scaled adaptive wing structure, effectiveness and producibility of the structural concept are demonstrated.
4. Morphing wing structure with controllable twist based on adaptive bending–twist coupling
International Nuclear Information System (INIS)
Raither, Wolfram; Heymanns, Matthias; Ermanni, Paolo; Bergamini, Andrea
2013-01-01
A novel semi-passive morphing airfoil concept based on variable bending–twist coupling induced by adaptive shear center location and torsional stiffness is presented. Numerical parametric studies and upscaling show that the concept relying on smart materials permits effective twist control while offering the potential of being lightweight and energy efficient. By means of an experimental characterization of an adaptive beam and a scaled adaptive wing structure, effectiveness and producibility of the structural concept are demonstrated. (paper)
5. Emergent Momentum-Space Skyrmion Texture on the Surface of Topological Insulators
Science.gov (United States)
Mohanta, Narayan; Kampf, Arno P.; Kopp, Thilo
The quantum anomalous Hall effect has been theoretically predicted and experimentally verified in magnetic topological insulators. In addition, the surface states of these materials exhibit a hedgehog-like spin'' texture in momentum space. Here, we apply the previously formulated low-energy model for Bi2Se3, a parent compound for magnetic topological insulators, to a slab geometry in which an exchange field acts only within one of the surface layers. In this sample set up, the hedgehog transforms into a skyrmion texture beyond a critical exchange field. This critical field marks a transition between two topologically distinct phases. The topological phase transition takes place without energy gap closing at the Fermi level and leaves the transverse Hall conductance unchanged and quantized to e2 / 2 h . The momentum-space skyrmion texture persists in a finite field range. It may find its realization in hybrid heterostructures with an interface between a three-dimensional topological insulator and a ferromagnetic insulator. The work was supported by the Deutsche Forschungsgemeinschaft through TRR 80.
6. Analytic self-gravitating Skyrmions, cosmological bounces and AdS wormholes
Directory of Open Access Journals (Sweden)
Eloy Ayón-Beato
2016-01-01
Full Text Available We present a self-gravitating, analytic and globally regular Skyrmion solution of the Einstein–Skyrme system with winding number w=±1, in presence of a cosmological constant. The static spacetime metric is the direct product R×S3 and the Skyrmion is the self-gravitating generalization of the static hedgehog solution of Manton and Ruback with unit topological charge. This solution can be promoted to a dynamical one in which the spacetime is a cosmology of the Bianchi type-IX with time-dependent scale and squashing coefficients. Remarkably, the Skyrme equations are still identically satisfied for all values of these parameters. Thus, the complete set of field equations for the Einstein–Skyrme–Λ system in the topological sector reduces to a pair of coupled, autonomous, nonlinear differential equations for the scale factor and a squashing coefficient. These equations admit analytic bouncing cosmological solutions in which the universe contracts to a minimum non-vanishing size, and then expands. A non-trivial byproduct of this solution is that a minor modification of the construction gives rise to a family of stationary, regular configurations in General Relativity with negative cosmological constant supported by an SU(2 nonlinear sigma model. These solutions represent traversable AdS wormholes with NUT parameter in which the only “exotic matter” required for their construction is a negative cosmological constant.
7. Steady motion of skyrmions and domains walls under diffusive spin torques
KAUST Repository
Elías, Ricardo Gabriel
2017-03-09
We explore the role of the spin diffusion of conducting electrons in two-dimensional magnetic textures (domain walls and skyrmions) with spatial variation of the order of the spin precession length λex. The effect of diffusion reflects in four additional torques that are third order in spatial derivatives of magnetization and bilinear in λex and in the nonadiabatic parameter β′. In order to study the dynamics of the solitons when these diffusive torques are present, we derive the Thiele equation in the limit of steady motion and we compare the results with the nondiffusive limit. When considering a homogenous current these torques increase the longitudinal velocity of transverse domain walls of width Δ by a factor (λex/Δ)2(α/3), α being the magnetic damping constant. In the case of single skyrmions with core radius r0 these new contributions tend to increase the Magnus effect in an amount proportional to (λex/r0)2(1+2αβ′).
8. Steady motion of skyrmions and domains walls under diffusive spin torques
KAUST Repository
Elí as, Ricardo Gabriel; Vidal-Silva, Nicolas; Manchon, Aurelien
2017-01-01
We explore the role of the spin diffusion of conducting electrons in two-dimensional magnetic textures (domain walls and skyrmions) with spatial variation of the order of the spin precession length λex. The effect of diffusion reflects in four additional torques that are third order in spatial derivatives of magnetization and bilinear in λex and in the nonadiabatic parameter β′. In order to study the dynamics of the solitons when these diffusive torques are present, we derive the Thiele equation in the limit of steady motion and we compare the results with the nondiffusive limit. When considering a homogenous current these torques increase the longitudinal velocity of transverse domain walls of width Δ by a factor (λex/Δ)2(α/3), α being the magnetic damping constant. In the case of single skyrmions with core radius r0 these new contributions tend to increase the Magnus effect in an amount proportional to (λex/r0)2(1+2αβ′).
9. 7 CFR 319.56-48 - Conditions governing the entry of baby squash and baby courgettes from Zambia.
Science.gov (United States)
2010-01-01
... 7 Agriculture 5 2010-01-01 2010-01-01 false Conditions governing the entry of baby squash and baby... Fruits and Vegetables § 319.56-48 Conditions governing the entry of baby squash and baby courgettes from Zambia. Baby squash (Curcurbita maxima Duchesne) and baby courgettes (C. pepo. L.) measuring 10 to 25...
10. The baby boom, the baby bust, and the housing market.
Science.gov (United States)
Mankiw, N G; Weil, D N
1989-05-01
This paper explores the impact of demographic changes on the housing market in the US, 1st by reviewing the facts about the Baby Boom, 2nd by linking age and housing demand using census data for 1970 and 1980, 3rd by computing the effect of demand on price of housing and on the quantity of residential capital, and last by constructing a theoretical model to plot the predictability of the jump in demand caused by the Baby Boom. The Baby Boom in the U.S. lasted from 1946-1964, with a peak in 1957 when 4.3 million babies were born. In 1980 19.7% of the population were aged 20-30, compared to 13.3% in 1960. Demand for housing was modeled for a given household from census data, resulting in the finding that demand rises sharply at age 20-30, then declines after age 40 by 1% per year. Thus between 1970 and 1980 the real value of housing for an adult at any given age jumped 50%, while the real disposable personal income per capita rose 22%. The structure of demand is such that the swelling in the rate of growth in housing demand peaked in 1980, with a rate of 1.66% per year. Housing demand and real price of housing were highly correlated and inelastic. If this relationship holds in the future, the real price of housing should fall about 3% per year, or 47% by 2007. The theoretical model, a variation of the Poterba model, ignoring inflation and taxation, suggests that fluctuations in prices caused by changes in demand are not foreseen by the market, even though they are predictable in principle 20 years in advance. As the effects of falling housing prices become apparent, there may be a potential for economic instability, but people may be induced to save more because their homes will no longer provide the funds for retirement.
11. ["Designer baby" changed to French for "double hope baby"].
Science.gov (United States)
Fagniez, P-L; Loriau, J; Tayar, C
2005-10-01
Scientific advances during the last decades regarding potential intervention on embryos arouse many questions in society to prepare the ground concerning the limits that should be set for these practices. For the first time in 1994, a parliamentary proceeding allowed the definition of a French model of bioethics through laws of the same name. These laws, among others, authorized in a well and strictly defined setting the practice of preimplantation genetic diagnosis (PGD). Because of technical progress concerning PGD, new questions arose, especially concerning the accomplishment of designer babies. The French Chamber of Representatives came in with a new law that banishes the concept of designer babies and replaces it with another concept: double hope babies, in French "bébé du double espoir". A first hope of a pregnancy giving birth to a healthy child and the second being that this child conceived with the aid of PGD could help treat an elder brother. Because of the issuing of two specific laws in a ten years interval, France occupies a privileged place in a Europe where bioethical issues continue to be debated, particularly PGD.
12. Present situation of 'baby cyclotron'
International Nuclear Information System (INIS)
1981-01-01
A ''baby cyclotron'' has been developed by the Japan Steel Works, Ltd. Its No. 1 model (proton 9.4 MeV) was delivered to the Nakano Hospital of National Sanatorium in March, 1979. It is being used successfully for the production of 11 C, 13 N and 15 O and labeled compounds. The proton or deuteron particles accelerated in the cyclotron collide on target materials. The target box, which is automatically changeable, is directly installed to the accelerating box, thereby taking the safety measures for any leaking radiation. The following matters are described: the production of short-lived radioisotopes (RI yields and treatment); the processes of production in the Nakano Hospital, with No. 1 baby cyclotron, including the photosynthesis of labeled compounds such as 11 C-labeled glucose; the research on the automation in the synthesis of organic labeled compounds like 11 C-palmitic acid. (J.P.N.)
13. A novel role for Twist-1 in pulp homeostasis.
Science.gov (United States)
Galler, K M; Yasue, A; Cavender, A C; Bialek, P; Karsenty, G; D'Souza, R N
2007-10-01
The molecular mechanisms that maintain the equilibrium of odontoblast progenitor cells in dental pulp are unknown. Here we tested whether homeostasis in dental pulp is modulated by Twist-1, a nuclear protein that partners with Runx2 during osteoblast differentiation. Our analysis of Twist-1(+/-) mice revealed phenotypic changes that involved an earlier onset of dentin matrix formation, increased alkaline phosphatase activity, and pulp stones within the pulp. RT-PCR analyses revealed Twist-1 expression in several adult organs, including pulp. Decreased levels of Twist-1 led to higher levels of type I collagen and Dspp gene expression in perivascular cells associated with the pulp stones. In mice heterozygous for both Twist-1 and Runx2 inactivation, the phenotype of pulp stones appeared completely rescued. These findings suggest that Twist-1 plays a key role in restraining odontoblast differentiation, thus maintaining homeostasis in dental pulp. Furthermore, Twist-1 functions in dental pulp are dependent on its interaction with Runx2.
14. Universal acquired melanosis (Carbon baby
Directory of Open Access Journals (Sweden)
Kaviarasan P
2008-01-01
Full Text Available We report a 3-year-old girl born with fair complexion which became darker. The color change was insidious in onset at the age of 5 months, asymptomatic and progressive involving the entire body surface. Histopathology revealed increased pigmentation of the epidermal basal layer. Universal acquired melanosis is a rare form of hypermelanosis which was synonymously referred to as "Carbon baby". This is a rare presentation with only one earlier case report.
15. Advanced Portable Preterm Baby Incubator
OpenAIRE
Shaib , M.; Rashid , M.; Hamawy , L.; Arnout , M.; Majzoub , I. ,; Zaylaa , A. ,
2017-01-01
International audience; Nearly 20 million premature and Low Birth Weight infants are born each year in developing countries, 4 million die within their first month. These deaths occur due to the unavailability or unreliability of traditional incubators. Moreover, although Telemedicine is helpful in rural areas, the shortage of healthcare providers have made it inaccessible in both basic healthcare. Thereby, traditional preterm baby and low-birth weight incubators and therapeutic techniques la...
16. Baby universes in string theory
International Nuclear Information System (INIS)
Dijkgraaf, Robbert; Gopakumar, Rajesh; Ooguri, Hirosi; Vafa, Cumrun
2006-01-01
We argue that the holographic description of four-dimensional Bogomol'nyi-Prasad-Sommerfield black holes naturally includes multicenter solutions. This suggests that the holographic dual to the gauge theory is not a single AdS 2 xS 2 but a coherent ensemble of them. We verify this in a particular class of examples, where the two-dimensional Yang-Mills theory gives a holographic description of the black holes obtained by branes wrapping Calabi-Yau cycles. Using the free fermionic formulation, we show that O(e -N ) nonperturbative effects entangle the two Fermi surfaces. In an Euclidean description, the wave function of the multicenter black holes gets mapped to the Hartle-Hawking wave function of baby universes. This provides a concrete realization, within string theory, of effects that can be interpreted as the creation of baby universes. We find that, at least in the case we study, the baby universes do not lead to a loss of quantum coherence, in accord with general arguments
17. Energy efficient and fast reversal of a fixed skyrmion two-terminal memory with spin current assisted by voltage controlled magnetic anisotropy
Science.gov (United States)
Bhattacharya, Dhritiman; Mamun Al-Rashid, Md; Atulasimha, Jayasimha
2017-10-01
Recent work (P-H Jang et al 2015 Appl. Phys. Lett. 107 202401, J. Sampaio et al 2016 Appl. Phys. Lett. 108 112403) suggests that ferromagnetic reversal with spin transfer torque (STT) requires more current in a system in the presence of Dzyaloshinskii-Moriya interaction (DMI) than switching a typical ferromagnet of the same dimensions and perpendicular magnetic anisotropy (PMA). However, DMI promotes the stabilization of skyrmions and we report that when perpendicular anisotropy is modulated (reduced) for both the skyrmion and ferromagnet, it takes a much smaller current to reverse the fixed skyrmion than to reverse the ferromagnet in the same amount of time, or the skyrmion reverses much faster than the ferromagnet at similar levels of current. We show with rigorous micromagnetic simulations that skyrmion switching proceeds along a different path at very low PMA, which results in a significant reduction in the spin current or time required for reversal. This can offer potential for memory applications where a relatively simple modification of the standard STT-RAM (to include a heavy metal adjacent to the soft magnetic layer and with appropriate design of the tunnel barrier) can lead to an energy efficient and fast magnetic memory device based on the reversal of fixed skyrmions.
18. A New Twisting Somersault: 513XD
Science.gov (United States)
Tong, William; Dullin, Holger R.
2017-12-01
We present the mathematical framework of an athlete modelled as a system of coupled rigid bodies to simulate platform and springboard diving. Euler's equations of motion are generalised to non-rigid bodies and are then used to innovate a new dive sequence that in principle can be performed by real-world athletes. We begin by assuming that shape changes are instantaneous so that the equations of motion simplify enough to be solved analytically, and then use this insight to present a new dive (513XD) consisting of 1.5 somersaults and five twists using realistic shape changes. Finally, we demonstrate the phenomenon of converting pure somersaulting motion into pure twisting motion by using a sequence of impulsive shape changes, which may have applications in other fields such as space aeronautics.
19. Chiral tunneling in a twisted graphene bilayer.
Science.gov (United States)
He, Wen-Yu; Chu, Zhao-Dong; He, Lin
2013-08-09
The perfect transmission in a graphene monolayer and the perfect reflection in a Bernal graphene bilayer for electrons incident in the normal direction of a potential barrier are viewed as two incarnations of the Klein paradox. Here we show a new and unique incarnation of the Klein paradox. Owing to the different chiralities of the quasiparticles involved, the chiral fermions in a twisted graphene bilayer show an adjustable probability of chiral tunneling for normal incidence: they can be changed from perfect tunneling to partial or perfect reflection, or vice versa, by controlling either the height of the barrier or the incident energy. As well as addressing basic physics about how the chiral fermions with different chiralities tunnel through a barrier, our results provide a facile route to tune the electronic properties of the twisted graphene bilayer.
20. Factorising the 3D topologically twisted index
Energy Technology Data Exchange (ETDEWEB)
Cabo-Bizet, Alejandro [Instituto de Astronomía y Física del Espacio (CONICET-UBA),Ciudad Universitaria, C.P. 1428, Buenos Aires (Argentina)
2017-04-20
We explore the path integration — upon the contour of hermitian (non-auxliary) field configurations — of topologically twisted N=2 Chern-Simons-matter theory (TTCSM) on S{sub 2} times a segment. In this way, we obtain the formula for the 3D topologically twisted index, first as a convolution of TTCSM on S{sub 2} times halves of S{sub 1}, second as TTCSM on S{sub 2} times S{sub 1} — with a puncture, — and third as TTCSM on S{sub 2}×S{sub 1}. In contradistinction to the first two cases, in the third case, the vector multiplet auxiliary field D is constrained to be anti-hermitian.
1. IRONY IN CHARLES DICKEN'S OLIVER TWIST
Directory of Open Access Journals (Sweden)
Ika Kana Trisnawati
2016-05-01
Full Text Available This paper describes the types of irony used by Charles Dickens in his notable early work, Oliver Twist, as well as the reasons the irony was chosen. As a figurative language, irony is utilized to express one’s complex feelings without truly saying them. In Oliver Twist, Dickens brought the readers some real social issues wrapped in dark, deep written expressions of irony uttered by the characters of his novel. Undoubtedly, the novel had left an impact to the British society at the time. The irony Dickens displayed here includes verbal, situational, and dramatic irony. His choice of irony made sense as he intended to criticize the English Poor Laws and to touch the public sentiment. He wanted to let the readers go beyond what was literally written and once they discovered what the truth was, they would eventually understand Dickens’ purposes.
2. Leibniz algebroids, twistings and exceptional generalized geometry
Science.gov (United States)
Baraglia, D.
2012-05-01
We investigate a class of Leibniz algebroids which are invariant under diffeomorphisms and symmetries involving collections of closed forms. Under appropriate assumptions we arrive at a classification which in particular gives a construction starting from graded Lie algebras. In this case the Leibniz bracket is a derived bracket and there are higher derived brackets resulting in an L∞-structure. The algebroids can be twisted by a non-abelian cohomology class and we prove that the twisting class is described by a Maurer-Cartan equation. For compact manifolds we construct a Kuranishi moduli space of this equation which is shown to be affine algebraic. We explain how these results are related to exceptional generalized geometry.
3. Valve-aided twisted Savonius rotor
Energy Technology Data Exchange (ETDEWEB)
Jaya Rajkumar, M.; Saha, U.K.
2006-05-15
Accessories, such as end plates, deflecting plates, shielding and guide vanes, may increase the power of a Savonius rotor, but make the system structurally complex. In such cases, the rotor can develop a relatively large torque at small rotational speeds and is cheap to build, however it harnesses only a small fraction of the incident wind energy. Another proposition for increasing specific output is to place non-return valves inside the concave side of the blades. Such methods have been studied experimentally with a twisted-blade Thus improving a Savonius rotor's energy capture. This new concept has been named as the 'Valve-Aided Twisted Savonius'rotor. Tests were conducted in a low-speed wind tunnel to evaluate performance. This mechanism is found to be independent of flow direction, and shows potential for large machines. [Author].
4. Chiral Tunnelling in Twisted Graphene Bilayer
OpenAIRE
He, Wen-Yu; Chu, Zhao-Dong; He, Lin
2013-01-01
The perfect transmission in graphene monolayer and the perfect reflection in Bernal graphene bilayer for electrons incident in the normal direction of a potential barrier are viewed as two incarnations of the Klein paradox. Here we show a new and unique incarnation of the Klein paradox. Owing to the different chiralities of the quasiparticles involved, the chiral fermions in twisted graphene bilayer shows adjustable probability of chiral tunnelling for normal incidence: they can be changed fr...
5. Vacuum expectation value of twist fields
Science.gov (United States)
Belitsky, A. V.
2017-09-01
Twist fields emerge in a number of physical applications ranging from entanglement entropy to scattering amplitudes in four-dimensional gauge theories. In this work, their vacuum expectation values are studied in the path integral framework. By performing a gauge transformation, their correlation functions are reduced to field theory of matter fields in external Aharonov-Bohm vortices. The resulting functional determinants are then analyzed within the zeta-function regularization for the spectrum of Bessel zeros, and concise formulas are derived.
6. Leibniz algebroids, twistings and exceptional generalized geometry
OpenAIRE
Baraglia, David
2011-01-01
We investigate a class of Leibniz algebroids which are invariant under diffeomorphisms and symmetries involving collections of closed forms. Under appropriate assumptions we arrive at a classification which in particular gives a construction starting from graded Lie algebras. In this case the Leibniz bracket is a derived bracket and there are higher derived brackets resulting in an $L_\\infty$-structure. The algebroids can be twisted by a non-abelian cohomology class and we prove that the twis...
7. Exploring exotic states with twisted boundary conditions
International Nuclear Information System (INIS)
2017-01-01
he goal of this thesis is to develop methods to study the nature and properties of exotic hadrons from lattice simulations. The main focus lies in the application of twisted boundary conditions. The thesis consists of a general introduction and the collection of three papers, represented respectively in three chapters. The introduction of the thesis reviews the theoretical background, which is further used in the rest of the thesis. Further implementing partially twisted boundary conditions in the scalar sector of lattice QCD is studied. Then we develop a method to study the content of the exotic hadrons by determining the wave function renormalization constant from lattice simulations, exploiting the dependence of the spectrum on the twisted boundary conditions. The final chapter deals with a novel method to study the multi-channel scattering problem in a finite volume, which is relevant for exotic states. Its key idea is to extract the complex hadron-hadron optical potential, avoiding the difficulties, associated with the solution of the multi-channel Luescher equation.
8. Exploring exotic states with twisted boundary conditions
Energy Technology Data Exchange (ETDEWEB)
2017-09-11
he goal of this thesis is to develop methods to study the nature and properties of exotic hadrons from lattice simulations. The main focus lies in the application of twisted boundary conditions. The thesis consists of a general introduction and the collection of three papers, represented respectively in three chapters. The introduction of the thesis reviews the theoretical background, which is further used in the rest of the thesis. Further implementing partially twisted boundary conditions in the scalar sector of lattice QCD is studied. Then we develop a method to study the content of the exotic hadrons by determining the wave function renormalization constant from lattice simulations, exploiting the dependence of the spectrum on the twisted boundary conditions. The final chapter deals with a novel method to study the multi-channel scattering problem in a finite volume, which is relevant for exotic states. Its key idea is to extract the complex hadron-hadron optical potential, avoiding the difficulties, associated with the solution of the multi-channel Luescher equation.
9. Transverse kink oscillations in the presence of twist
Science.gov (United States)
2012-12-01
Context. Magnetic twist is thought to play an important role in coronal loops. The effects of magnetic twist on stable magnetohydrodynamic (MHD) waves is poorly understood because they are seldom studied for relevant cases. Aims: The goal of this work is to study the fingerprints of magnetic twist on stable transverse kink oscillations. Methods: We numerically calculated the eigenmodes of propagating and standing MHD waves for a model of a loop with magnetic twist. The azimuthal component of the magnetic field was assumed to be small in comparison to the longitudinal component. We did not consider resonantly damped modes or kink instabilities in our analysis. Results: For a nonconstant twist the frequencies of the MHD wave modes are split, which has important consequences for standing waves. This is different from the degenerated situation for equilibrium models with constant twist, which are characterised by an azimuthal component of the magnetic field that linearly increases with the radial coordinate. Conclusions: In the presence of twist standing kink solutions are characterised by a change in polarisation of the transverse displacement along the tube. For weak twist, and in the thin tube approximation, the frequency of standing modes is unaltered and the tube oscillates at the kink speed of the corresponding straight tube. The change in polarisation is linearly proportional to the degree of twist. This has implications with regard to observations of kink modes, since the detection of this variation in polarisation can be used as an indirect method to estimate the twist in oscillating loops.
10. Design optimization for active twist rotor blades
Science.gov (United States)
Mok, Ji Won
11. Simulating QCD at the physical point with Nf=2 Wilson twisted mass fermions at maximal twist
International Nuclear Information System (INIS)
Abdel-Rehim, A.; Alexandrou, C.; Cyprus Univ. Nicosia; Burger, F.
2015-12-01
We present simulations of QCD using N f =2 dynamical Wilson twisted mass lattice QCD with physical value of the pion mass and at one value of the lattice spacing. Such simulations at a∼0.09 fm became possible by adding the clover term to the action. While O(a) improvement is still guaranteed by Wilson twisted mass fermions at maximal twist, the introduction of the clover term reduces O(a 2 ) cutoff effects related to isospin symmetry breaking. We give results for a set of phenomenologically interesting observables like pseudo-scalar masses and decay constants, quark masses and the anomalous magnetic moments of leptons. We mostly find remarkably good agreement with phenomenology, even though we cannot take the continuum and thermodynamic limits.
12. Self-dual Skyrmions on the spheres S2 N +1
Science.gov (United States)
Amari, Y.; Ferreira, L. A.
2018-04-01
We construct self-dual sectors for scalar field theories on a (2 N +2 )-dimensional Minkowski space-time with the target space being the 2 N +1 -dimensional sphere S2 N +1. The construction of such self-dual sectors is made possible by the introduction of an extra functional in the action that renders the static energy and the self-duality equations conformally invariant on the (2 N +1 )-dimensional spatial submanifold. The conformal and target-space symmetries are used to build an ansatz that leads to an infinite number of exact self-dual solutions with arbitrary values of the topological charge. The five-dimensional case is discussed in detail, where it is shown that two types of theories admit self-dual sectors. Our work generalizes the known results in the three-dimensional case that lead to an infinite set of self-dual Skyrmion solutions.
13. Skyrmion formation and optical spin-Hall effect in an expanding coherent cloud of indirect excitons.
Science.gov (United States)
Vishnevsky, D V; Flayac, H; Nalitov, A V; Solnyshkov, D D; Gippius, N A; Malpuech, G
2013-06-14
We provide a theoretical description of the polarization pattern and phase singularities experimentally evidenced recently in a condensate of indirect excitons [H. High et al., Nature 483, 584 (2012)]. We show that the averaging of the electron and hole orbital motion leads to a comparable spin-orbit interaction for both types of carriers. We demonstrate that the interplay between a radial coherent flux of bright indirect excitons and the Dresselhaus spin-orbit interaction results in the formation of spin domains and of topological defects similar to Skyrmions. We reproduce qualitatively all the features of the experimental data and obtain a polarization pattern as in the optical spin-Hall effect despite the different symmetry of the spin-orbit interactions.
14. The half-skyrmion phase in a chiral-quark model
International Nuclear Information System (INIS)
Mantovani Sarti, Valentina; Vento, Vicente
2014-01-01
The Chiral Dilaton Model, where baryons arise as non-topological solitons built from the interaction of quarks and chiral mesons, shows in the high density low temperature regime a two phase scenario in the nuclear matter phase diagram. Dense soliton matter described by the Wigner–Seitz approximation generates a periodic potential in terms of the sigma and pion fields that leads to the formation of a band structure. The analysis up to three times nuclear matter density shows that soliton matter undergoes two separate phase transitions: a delocalization of the baryon number density leading to B=1/2 structures, as in skyrmion matter, at moderate densities, and quark deconfinement at larger densities. This description fits well into the so-called quarkyonic phase where, before deconfinement, nuclear matter should undergo structural changes involving the restoration of fundamental symmetries of QCD
15. Theory of high-resolution tunneling spin transport on a magnetic skyrmion
Science.gov (United States)
Palotás, Krisztián; Rózsa, Levente; Szunyogh, László
2018-05-01
Tunneling spin transport characteristics of a magnetic skyrmion are described theoretically in magnetic scanning tunneling microscopy (STM). The spin-polarized charge current in STM (SP-STM) and tunneling spin transport vector quantities, the longitudinal spin current and the spin transfer torque, are calculated in high spatial resolution within the same theoretical framework. A connection between the conventional charge current SP-STM image contrasts and the magnitudes of the spin transport vectors is demonstrated that enables the estimation of tunneling spin transport properties based on experimentally measured SP-STM images. A considerable tunability of the spin transport vectors by the involved spin polarizations is also highlighted. These possibilities and the combined theory of tunneling charge and vector spin transport pave the way for gaining deep insight into electric-current-induced tunneling spin transport properties in SP-STM and to the related dynamics of complex magnetic textures at surfaces.
16. Acute appendicitis in a premature baby
International Nuclear Information System (INIS)
Beluffi, Giampiero; Alberici, Elisa
2002-01-01
A case of acute appendicitis in a premature baby in whom diagnosis was suggested on plain films of the abdomen is presented. In this baby air in a hollow viscus suspected of being an enlarged appendix was the clue to diagnosis. The diagnostic dilemma of this rare and life-threatening condition in premature babies and newborns is underlined. The relevance of different imaging modalities and of different findings in this age group is discussed. Awareness of this rare condition and possible differential diagnosis in newborns and premature babies is stressed. (orig.)
17. Brane-induced Skyrmion on S3: Baryonic matter in holographic QCD
International Nuclear Information System (INIS)
Nawa, Kanabu; Suganuma, Hideo; Kojo, Toru
2009-01-01
We study baryonic matter in holographic QCD with D4/D8/D8 multi-D brane system in type IIA superstring theory. The baryon is described as the 'brane-induced Skyrmion', which is a topologically nontrivial chiral soliton in the four-dimensional meson effective action induced by holographic QCD. We employ the ''truncated-resonance model'' approach for the baryon analysis, including pion and ρ meson fields below the ultraviolet cutoff scale M KK ∼1 GeV, to keep the holographic duality with QCD. We describe the baryonic matter in large N c as single brane-induced Skyrmion on the three-dimensional closed manifold S 3 with finite radius R. The interactions between baryons are simulated by the curvature of the closed manifold S 3 , and the decrease of the size of S 3 represents the increase of the total baryon-number density in the medium in this modeling. We investigate the energy density, the field configuration, the mass and the root-mean-square radius of single baryon on S 3 as the function of its radius R. We find a new picture of 'pion dominance' near the critical density in the baryonic matter, where all the (axial) vector meson fields disappear and only the pion fields survive. We also find the swelling phenomena of the baryons as the precursor of the deconfinement, and propose the mechanism of the swelling in the general context of QCD. The properties of the deconfinement and the chiral symmetry restoration in the baryonic matter are examined by taking the proper order parameters. We also compare our truncated-resonance model with another instanton description of the baryon in holographic QCD, considering the role of cutoff scale M KK .
18. Ten helical twist angles of B-DNA
Energy Technology Data Exchange (ETDEWEB)
Kabsch, W; Sander, C; Trifonov, E N
1982-01-01
On the assumption that the twist angles between adjacent base-pairs in the DNA molecule are additive a linear system of 40 equations was derived from experimental measurements of the total twist angles for different pieces of DNA of known sequences. This system of equations is found to be statistically consistent providing a solution for all ten possible twist angles of B-DNA by a least squares fitting procedure. Four of the calculated twist angles were not known before. The other six twist angles calculated are very close to the experimentally measured ones. The data used were obtained by the electrophoretic band-shift method, crystallography and nuclease digestion of DNA adsorbed to mica or Ca-phosphate surface. The validity of the principle of additivity of the twist angles implies that the angle between any particular two base-pairs is a function of only these base-pairs, independent of nearest neighbors.
19. Can Babies Learn to Read? A Randomized Trial of Baby Media
Science.gov (United States)
Neuman, Susan B.; Kaefer, Tanya; Pinkham, Ashley; Strouse, Gabrielle
2014-01-01
Targeted to children as young as 3 months old, there is a growing number of baby media products that claim to teach babies to read. This randomized controlled trial was designed to examine this claim by investigating the effects of a best-selling baby media product on reading development. One hundred and seventeen infants, ages 9 to 18 months,…
20. Extended skyrmion lattice scattering and long-time memory in the chiral magnet Fe1 -xCoxSi
Science.gov (United States)
Bannenberg, L. J.; Kakurai, K.; Qian, F.; Lelièvre-Berna, E.; Dewhurst, C. D.; Onose, Y.; Endoh, Y.; Tokura, Y.; Pappas, C.
2016-09-01
Small angle neutron scattering measurements on a bulk single crystal of the doped chiral magnet Fe1 -xCoxSi with x =0.3 reveal a pronounced effect of the magnetic history and cooling rates on the magnetic phase diagram. The extracted phase diagrams are qualitatively different for zero and field cooling and reveal a metastable skyrmion lattice phase outside the A phase for the latter case. These thermodynamically metastable skyrmion lattice correlations coexist with the conical phase and can be enhanced by increasing the cooling rate. They appear in a wide region of the phase diagram at temperatures below the A phase but also at fields considerably smaller or higher than the fields required to stabilize the A phase.
1. Interface-induced chiral domain walls, spin spirals and skyrmions revealed by spin-polarized scanning tunneling microscopy.
Science.gov (United States)
von Bergmann, Kirsten; Kubetzka, André; Pietzsch, Oswald; Wiesendanger, Roland
2014-10-01
The spin textures of ultra-thin magnetic layers exhibit surprising variety. The loss of inversion symmetry at the interface of the magnetic layer and substrate gives rise to the so-called Dzyaloshinskii-Moriya interaction which favors non-collinear spin arrangements with unique rotational sense. Here we review the application of spin-polarized scanning tunneling microscopy to such systems, which has led to the discovery of interface-induced chiral domain walls and spin spirals. Recently, different interface-driven skyrmion lattices have been found, and the writing as well as the deleting of individual skyrmions based on local spin-polarized current injection has been demonstrated. These interface-induced non-collinear magnetic states offer new exciting possibilities to study fundamental magnetic interactions and to tailor material properties for spintronic applications.
2. Interlayer Exchange Coupling: A General Scheme Turning Chiral Magnets into Magnetic Multilayers Carrying Atomic-Scale Skyrmions.
Science.gov (United States)
Nandy, Ashis Kumar; Kiselev, Nikolai S; Blügel, Stefan
2016-04-29
We report on a general principle using interlayer exchange coupling to extend the regime of chiral magnetic films in which stable or metastable magnetic Skyrmions can appear at a zero magnetic field. We verify this concept on the basis of a first-principles model for a Mn monolayer on a W(001) substrate, a prototype chiral magnet for which the atomic-scale magnetic texture is determined by the frustration of exchange interactions, impossible to unwind by laboratory magnetic fields. By means of ab initio calculations for the Mn/W_{m}/Co_{n}/Pt/W(001) multilayer system we show that for certain thicknesses m of the W spacer and n of the Co reference layer, the effective field of the reference layer fully substitutes the required magnetic field for Skyrmion formation.
3. Twisted Vanes Would Enhance Fuel/Air Mixing In Turbines
Science.gov (United States)
Nguyen, H. Lee; Micklow, Gerald J.; Dogra, Anju S.
1994-01-01
Computations of flow show performance of high-shear airblast fuel injector in gas-turbine engine enhanced by use of appropriately proportioned twisted (instead of flat) dome swirl vanes. Resultant more nearly uniform fuel/air mixture burns more efficiently, emitting smaller amounts of nitrogen oxides. Twisted-vane high-shear airblast injectors also incorporated into paint sprayers, providing advantages of low pressure drop characteristic of airblast injectors in general and finer atomization of advanced twisted-blade design.
4. Twisted rudder for reducing fuel-oil consumption
Directory of Open Access Journals (Sweden)
Jung-Hun Kim
2014-09-01
Full Text Available Three twisted rudders fit for large container ships have been developed; 1 the Z-twisted rudder that is an asymmetry type taking into consideration incoming flow angles of the propeller slipstream, 2 the ZB-twisted rudder with a rudder bulb added onto the Z-twisted rudder, and 3 the ZB-F twisted rudder with a rudder fin attached to the ZB-twisted rudder. The twisted rudders have been designed computationally with the hydrodynamic characteristics in a self-propulsion condition in mind. The governing equation is the Navier-Stokes equations in an unsteady turbulent flow. The turbulence model applied is the Reynolds stress. The calculation was carried out in towing and self-propulsion conditions. The sliding mesh technique was employed to simulate the flow around the propeller. The speed performances of the ship with the twisted rudders were verified through model tests in a towing tank. The twisted versions showed greater performance driven by increased hull efficiency from less thrust deduction fraction and more effective wake fraction and decreased propeller rotating speed.
5. Higher twist contributions to deep-inelastic structure functions
International Nuclear Information System (INIS)
Bluemlein, J.; Boettcher, H.
2008-07-01
We report on a recent extraction of the higher twist contributions to the deep inelastic structure functions F ep,ed 2 (x,Q 2 ) in the large x region. It is shown that the size of the extracted higher twist contributions is strongly correlated with the higher order corrections applied to the leading twist part. A gradual lowering of the higher twist contributions going from NLO to N 4 LO is observed, where in the latter case only the leading large x terms were considered. (orig.)
6. Twisted sigma-model solitons on the quantum projective line
Science.gov (United States)
Landi, Giovanni
2018-04-01
On the configuration space of projections in a noncommutative algebra, and for an automorphism of the algebra, we use a twisted Hochschild cocycle for an action functional and a twisted cyclic cocycle for a topological term. The latter is Hochschild-cohomologous to the former and positivity in twisted Hochschild cohomology results into a lower bound for the action functional. While the equations for the critical points are rather involved, the use of the positivity and the bound by the topological term lead to self-duality equations (thus yielding twisted noncommutative sigma-model solitons, or instantons). We present explicit nontrivial solutions on the quantum projective line.
7. Bound states on the lattice with partially twisted boundary conditions
International Nuclear Information System (INIS)
Agadjanov, D.; Guo, F.-K.; Ríos, G.; Rusetsky, A.
2015-01-01
We propose a method to study the nature of exotic hadrons by determining the wave function renormalization constant Z from lattice simulations. It is shown that, instead of studying the volume-dependence of the spectrum, one may investigate the dependence of the spectrum on the twisting angle, imposing twisted boundary conditions on the fermion fields on the lattice. In certain cases, e.g., the case of the DK bound state which is addressed in detail, it is demonstrated that the partial twisting is equivalent to the full twisting up to exponentially small corrections.
8. Twisting and Writhing with George Ellery Hale
Science.gov (United States)
Canfield, Richard C.
2013-06-01
Early in his productive career in astronomy, George Ellery Hale developed innovative solar instrumentation that allowed him to make narrow-band images. Among the solar phenomena he discovered were sunspot vortices, which he attributed to storms akin to cyclones in our own atmosphere. Using the concept of magnetic helicity, physicists and mathematicians describe the topology of magnetic fields, including twisting and writhing. Our contemporary understanding of Hale's vortices as a consequence of large-scale twist in sunspot magnetic fields hinges on a key property of helicity: conservation. I will describe the critical role that this property plays, when applied to twist and writhe, in a fundamental aspect of global solar magnetism: the hemispheric and solar cycle dependences of active region electric currents with respect to magnetic fields. With the advent of unbroken sequences of high-resolution magnetic images, such as those presently available from the Helioseismic and Magnetic Imager on Solar Dynamics Observatory, the flux of magnetic helicity through the photosphere can be observed quantitatively. As magnetic flux tubes buoy up through the convection zone, buffeted and shredded by turbulence, they break up into fragments by repeated random bifurcation. We track these rising flux fragments in the photosphere, and calculate the flux of energy and magnetic helicity there. Using a quantitative model of coronal currents, we also track connections between these fragments to calculate the energy and magnetic helicity stored at topological interfaces that are in some ways analogous to the storage of stress at faults in the Earth's crust. Comparison of these values to solar flares and interplanetary coronal mass ejections implies that this is the primary storage mechanism for energy and magnetic helicity released in those phenomena, and suggests a useful tool for quantitative prediction of geomagnetic storms.
9. Baby Blues’ highbush blueberry
Science.gov (United States)
Baby Blues’ is a new highbush blueberry from the U.S. Department of Agriculture-Agricultural Research Service (USDA-ARS) breeding program in Corvallis, OR, released in cooperation with Oregon State University’s Agricultural Experiment Station. ‘Baby Blues’ is a vigorous, high-yielding, very small-f...
10. Safe Sleep for Babies PSA (:60)
Centers for Disease Control (CDC) Podcasts
This 60 second public service announcement is based on the January 2018 CDC Vital Signs report. Every year, there are about 3,500 sleep-related deaths among U.S. babies. Learn how to create a safe sleep environment for babies.
11. Motor Development Programming in Trisomic-21 Babies
Science.gov (United States)
Sanz, Teresa; Menendez, Javier; Rosique, Teresa
2011-01-01
The present study contributes to the understanding of gross motor development in babies with Down's syndrome. Also, it facilitates the comprehension of the efficiency of the early motor stimulation as well as of beginning it as early as possible. We worked with two groups of babies with Down's syndrome, beginning the early motor training in each…
12. Designer Babies: Eugenics Repackaged or Consumer Options?
Science.gov (United States)
Baird, Stephen L.
2007-01-01
"Designer babies" is a term used by journalists and commentators--not by scientists--to describe several different reproductive technologies. These technologies have one thing in common: they give parents more control over what their offspring will be like. Designer babies are made possible by progress in three fields: (1) Advanced…
13. Three-parent baby: Is it ethical?
Science.gov (United States)
Dahiya, Neha; Garg, Suneela
2018-01-01
The UK was the first country to legalise mitochondrial donation in October 2015 (1). In 2016, the first three-parent baby was born in Mexico (2) and the US Food and Drug Administration declared that further research on mitochondrial donation is ethically permissible (3). It has now become an important issue, raising as it does, the spectre of "genetically modified designer babies".
14. Tracking Your Baby's Weight and Measurements
Science.gov (United States)
... Our Sponsors Ages & Stages Ages & Stages Ages and Stages Prenatal Baby (0-12 mos.) Toddler 1-3yrs. Preschool 3-5yrs Grade School 5-12yrs. Teen 12- ... the Word Shop AAP Find a Pediatrician Ages & Stages Prenatal Baby Bathing & Skin ... Teen Young Adult Healthy Children > Ages & Stages > ...
15. MONITORING BABY INCUBATOR SENTRAL DENGAN KOMUNIKASI WIRELESS
Directory of Open Access Journals (Sweden)
Ary Sulistyo Utomo
2018-04-01
180m. Pengujian suhu ruang baby incubator menggunakan termometer sebagai perbandingan dengan nilai suhu yang dibaca pada alat. Dari pengukuran diperoleh tingkat perbedaan 0% pada suhu 30oC dan 2,8% pada suhu 37oC. Kata kunci: baby incubator, sistem monitoring sentral, microsoft visual studio, arduino.
16. How to Keep Your Sleeping Baby Safe
Science.gov (United States)
... first hour. After that, or when the mother needs to sleep or cannot do skin-to-skin, babies should ... Back is Best New Crib Standards: What Parents Need to Know Safe Sleep for Babies (Video) The Healthy Children Show: Sleep ( ...
17. Development of Baby-EBM Interface System
International Nuclear Information System (INIS)
Mukhlis Mokhtar; Abu Bakar Ghazali; Muhammad Zahidee Taat
2010-01-01
This paper explains the works being done to develop an interface system for Baby-Electron Beam Machine (EBM). The function of the system is for the safety, controlling and monitoring the Baby-EBM. The integration for the system is using data acquisition (DAQ) hardware and LabVIEW to develop the software. (author)
18. Development of Baby-EBM Interface System
Energy Technology Data Exchange (ETDEWEB)
Mokhtar, Mukhlis; Ghazali, Abu Bakar; Taat, Muhammad Zahidee [Accelerator Development Center, Malaysian Nuclear Agency, Bangi, Kajang, Selangor (Malaysia), Technical Support Div.
2010-07-01
This paper explains the works being done to develop an interface system for Baby-Electron Beam Machine (EBM). The function of the system is for the safety, controlling and monitoring the Baby-EBM. The integration for the system is using data acquisition (DAQ) hardware and LabVIEW to develop the software. (author)
19. Teen Moms and Babies Benefit from Camping.
Science.gov (United States)
Goode, Marsha; Broesamle, Barbara
1987-01-01
Describes nine-day residential camp for Michigan teenage mothers/babies to enhance personal growth and develop responsible social skills. Outlines goals, pre-camp planning, staff, activities, evaluation. Reports 31 teen moms (ages 13-21) and 35 babies attended in 1986. Indicates participants were in therapy, experienced abuse, had low self-esteem,…
20. Twisted Polynomials and Forgery Attacks on GCM
DEFF Research Database (Denmark)
Abdelraheem, Mohamed Ahmed A. M. A.; Beelen, Peter; Bogdanov, Andrey
2015-01-01
Polynomial hashing as an instantiation of universal hashing is a widely employed method for the construction of MACs and authenticated encryption (AE) schemes, the ubiquitous GCM being a prominent example. It is also used in recent AE proposals within the CAESAR competition which aim at providing...... in an improved key recovery algorithm. As cryptanalytic applications of our twisted polynomials, we develop the first universal forgery attacks on GCM in the weak-key model that do not require nonce reuse. Moreover, we present universal weak-key forgeries for the nonce-misuse resistant AE scheme POET, which...
1. Optical twists in phase and amplitude
DEFF Research Database (Denmark)
Daria, Vincent R.; Palima, Darwin; Glückstad, Jesper
2011-01-01
where both phase and amplitude express a helical profile as the beam propagates in free space. Such a beam can be accurately referred to as an optical twister. We characterize optical twisters and demonstrate their capacity to induce spiral motion on particles trapped along the twisters’ path. Unlike LG...... beams, the far field projection of the twisted optical beam maintains a high photon concentration even at higher values of topological charge. Optical twisters have therefore profound applications to fundamental studies of light and atoms such as in quantum entanglement of the OAM, toroidal traps...
2. NMSBA - Twist Resist - Rotational Exercise Module
Energy Technology Data Exchange (ETDEWEB)
Walker, Aaron [Twist Resist, Albuquerque, NM (United States); Reece, Blake D. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Berger, Jason E. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Guido, Steven Frank [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Linker, Taylor [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
2016-08-01
This report contains a summary of the work completed to develop a modular, rotational exercise device. In the report are images, diagrams, and explanations of the efforts contributed to the project since its inception. The purpose of this document is to provide a walk-through of the progress on this project, from the initial design concepts to the final design and work done, so that the customer (Twist Resist), or individuals/firms who work on this project in the future will have a springboard of ideas/concepts to work from.
3. Deteksi Antibodi terhadap Cysticercus Cellulosae pada Babi Lokal yang Dipotong di Tempat Pemotongan Babi Panjer, Denpasar
Directory of Open Access Journals (Sweden)
Ida Bagus Ngurah Swacita
2016-03-01
Full Text Available Sistiserkosis merupakan penyakit yang bersifat zoonosis yang disebabkan oleh larva cacing pita Taenia solium yang disebut Cysticercus cellulosae. Di Indonesia terdapat tiga provinsi yang berstatus endemik penyakit sistiserkosis, salah satunya adalah provinsi Bali. Penelitian ini bertujuan untuk mendeteksi antibodi terhadap C. cellulosae pada babi lokal yang dipotong di tempat pemotongan babi Panjer, Denpasar. Sampel penelitian adalah 270 sampel serum babi lokal yang dipotong di tempat pemotongan babi Panjer, Denpasar Selatan. Babi lokal ini berasal dari Nusa Penida, Karangasem dan Negara. Sampel serum diuji dengan metode ELISA (Enzyme Linked Immunosorbent Assay indirect. Hasil penelitian menunjukkan bahwa antibodi C. cellulosae terdeteksi pada 33 sampel. Disimpulkan bahwa terdeteksi antibodi C. cellulosae pada 33 sampel dari 270 sampel serum babi lokal yang dipotong di tempat pemotongan babi Panjer, Denpasar.
4. Resuscitating the Baby after Shoulder Dystocia
Directory of Open Access Journals (Sweden)
Savas Menticoglou
2016-01-01
Full Text Available Background. To propose hypovolemic shock as a possible explanation for the failure to resuscitate some babies after shoulder dystocia and to suggest a change in clinical practice. Case Presentation. Two cases are presented in which severe shoulder dystocia was resolved within five minutes. Both babies were born without a heartbeat. Despite standard resuscitation by expert neonatologists, no heartbeat was obtained until volume resuscitation was started, at 25 minutes in the first case and 11 minutes in the second. After volume resuscitation circulation was restored, there was profound brain damage and the babies died. Conclusion. Unsuspected hypovolemic shock may explain some cases of failed resuscitation after shoulder dystocia. This may require a change in clinical practice. Rather than immediately clamping the cord after the baby is delivered, it is proposed that (1 the obstetrician delay cord clamping to allow autotransfusion of the baby from the placenta and (2 the neonatal resuscitators give volume much sooner.
5. Processing mechanics of alternate twist ply (ATP) yarn technology
Science.gov (United States)
Elkhamy, Donia Said
Ply yarns are important in many textile manufacturing processes and various applications. The primary process used for producing ply yarns is cabling. The speed of cabling is limited to about 35m/min. With the world's increasing demands of ply yarn supply, cabling is incompatible with today's demand activated manufacturing strategies. The Alternate Twist Ply (ATP) yarn technology is a relatively new process for producing ply yarns with improved productivity and flexibility. This technology involves self plying of twisted singles yarn to produce ply yarn. The ATP process can run more than ten times faster than cabling. To implement the ATP process to produce ply yarns there are major quality issues; uniform Twist Profile and yarn Twist Efficiency. The goal of this thesis is to improve these issues through process modeling based on understanding the physics and processing mechanics of the ATP yarn system. In our study we determine the main parameters that control the yarn twist profile. Process modeling of the yarn twist across different process zones was done. A computational model was designed to predict the process parameters required to achieve a square wave twist profile. Twist efficiency, a measure of yarn torsional stability and bulk, is determined by the ratio of ply yarn twist to singles yarn twist. Response Surface Methodology was used to develop the processing window that can reproduce ATP yarns with high twist efficiency. Equilibrium conditions of tensions and torques acting on the yarns at the self ply point were analyzed and determined the pathway for achieving higher twist efficiency. Mechanistic modeling relating equilibrium conditions to the twist efficiency was developed. A static tester was designed to zoom into the self ply zone of the ATP yarn. A computer controlled, prototypic ATP machine was constructed and confirmed the mechanistic model results. Optimum parameters achieving maximum twist efficiency were determined in this study. The
6. PREBIOTICS, INULIN AND BABY FOODS
Directory of Open Access Journals (Sweden)
S.V. Bel’mer
2010-01-01
Full Text Available Prebiotics play significant role in life support of microorganisms of human gastrointestinal tract, and normal functional state of intestinal biocenosis is sufficient condition for human health. Intestinal microbiocenosis is a component of regulation of proteins and lipids metabolism, vitamins synthesis, detoxication process in intestine, etc. prebiotics include a number of disaccharides (lactulose, oligosaccharides and polysaccharides (inulin, cellulose, etc.. Fructose polymer — inulin — provides growth of bifido- and lactobacteria, improves metabolism and has immunomodulating activity. Formation of intestinal micro biocenosis in infant is provided by prebiotics of breast milk. Further state of micro biocenosis, which is necessary for growth and development of child, is determined by adequate intake of prebiotics from fruits, vegetables and cereals. It is reasonable to use special baby foods fortified with prebiotics (for example, inulin.Key words: prebiotics, intestinal microflora, inulin.(Voprosy sovremennoi pediatrii — Current Pediatrics. – 2010;9(3:121-125
7. On reflection algebras and twisted Yangians
International Nuclear Information System (INIS)
Doikou, Anastasia
2005-01-01
It is well known that integrable models associated to rational R matrices give rise to certain non-Abelian symmetries known as Yangians. Analogously boundary symmetries arise when general but still integrable boundary conditions are implemented, as originally argued by Delius, Mackay, and Short from the field theory point of view, in the context of the principal chiral model on the half-line. In the present study we deal with a discrete quantum mechanical system with boundaries, that is the N site gl(n) open quantum spin chain. In particular, the open spin chain with two distinct types of boundary condition known as soliton preserving and soliton nonpreserving is considered. For both types of boundaries we present a unified framework for deriving the corresponding boundary nonlocal charges directly at the quantum level. The nonlocal charges are simply coproduct realizations of particular boundary quantum algebras called boundary or twisted Yangians, depending on the choice of boundary conditions. Finally, with the help of linear intertwining relations between the solutions of the reflection equation and the generators of the boundary or twisted Yangians we are able to exhibit the exact symmetry of the open spin chain, namely we show that a number of the boundary nonlocal charges are in fact conserved quantities
8. How the embryonic brain tube twists
Science.gov (United States)
Chen, Zi; Guo, Qiaohang; Forsch, Nickolas; Taber, Larry
2014-03-01
During early development, the tubular brain of the chick embryo undergoes a combination of progressive ventral bending and rightward torsion. This deformation is one of the major organ-level symmetry-breaking events in development. Available evidence suggests that bending is caused by differential growth, but the mechanism for torsion remains poorly understood. Since the heart almost always loops in the same direction that the brain twists, researchers have speculated that heart looping affects the direction of brain torsion. However, direct evidence is virtually nonexistent, nor is the mechanical origin of such torsion understood. In our study, experimental perturbations show that the bending and torsional deformations in the brain are coupled and that the vitelline membrane applies an external load necessary for torsion to occur. In addition, the asymmetry of the looping heart gives rise to the chirality of the twisted brain. A computational model is used to interpret these findings. Our work clarifies the mechanical origins of brain torsion and the associated left-right asymmetry, reminiscent of D'Arcy Thompson's view of biological form as diagram of forces''.
9. Drag Performance of Twist Morphing MAV Wing
Directory of Open Access Journals (Sweden)
Ismail N.I.
2016-01-01
Full Text Available Morphing wing is one of latest evolution found on MAV wing. However, due to few design problems such as limited MAV wing size and complicated morphing mechanism, the understanding of its aerodynamic behaviour was not fully explored. In fact, the basic drag distribution induced by a morphing MAV wing is still remained unknown. Thus, present work is carried out to compare the drag performance between a twist morphing wing with membrane and rigid MAV wing design. A quasi-static aeroelastic analysis by using the Ansys-Fluid Structure Interaction (FSI method is utilized in current works to predict the drag performance a twist morphing MAV wing design. Based on the drag pattern study, the results exhibits that the morphing wing has a partial similarities in overall drag pattern with the baseline (membrane and rigid wing. However, based CD analysis, it shows that TM wing induced higher CD magnitude (between 25% to 82% higher than to the baseline wing. In fact, TM wing also induced the largest CD increment (about 20% to 27% among the wings. The visualization on vortex structure revealed that TM wing also produce larger tip vortex structure (compared to baseline wings which presume to promote higher induce drag component and subsequently induce its higher CD performance.
10. Strong CP, flavor, and twisted split fermions
International Nuclear Information System (INIS)
Harnik, Roni; Perez, Gilad; Schwartz, Matthew D.; Shirman, Yuri
2005-01-01
We present a natural solution to the strong CP problem in the context of split fermions. By assuming CP is spontaneously broken in the bulk, a weak CKM phase is created in the standard model due to a twisting in flavor space of the bulk fermion wavefunctions. But the strong CP phase remains zero, being essentially protected by parity in the bulk and CP on the branes. As always in models of spontaneous CP breaking, radiative corrections to theta bar from the standard model are tiny, but even higher dimension operators are not that dangerous. The twisting phenomenon was recently shown to be generic, and not to interfere with the way that split fermions naturally weaves small numbers into the standard model. It follows that out approach to strong CP is compatible with flavor, and we sketch a comprehensive model. We also look at deconstructed version of this setup which provides a viable 4D model of spontaneous CP breaking which is not in the Nelson-Barr class. (author)
11. Summing skyrmions
International Nuclear Information System (INIS)
Jackson, A.D.; Weiss, C.; Wirzba, A.
1990-01-01
The Skyrme model has the same high density behavior as a free quark gas. However, the inclusion of higher-order terms spoils this agreement. We consider the all-order sum of a class of chiral invariant Lagrangians of even order in L μ suggested by Marleau. We prove Marleau's conjecture that these terms are of second order in the derivatives of the chiral angle for the hedgehog case and show the terms are unique under the additional condition that, for each order, the identity map on the 3-sphere S 3 (L) is a solution. The general form of the summation can be restricted by physical constraints leading to stable results. Under the assumption that the Lagrangian scales like the non-linear sigma model at low densities and like the free quark gas at high densities, we prove that a chiral phase transition must occur. (orig.)
12. Quadratic Twists of Rigid Calabi–Yau Threefolds Over
DEFF Research Database (Denmark)
Gouvêa, Fernando Q.; Kiming, Ian; Yui, Noriko
2013-01-01
of weight 4 on some Γ 0(N). We show that quadratic twisting of a threefold corresponds to twisting the attached newform by quadratic characters and illustrate with a number of obvious and not so obvious examples. The question is motivated by the deeper question of which newforms of weight 4 on some Γ 0(N...
13. Bend-twist coupling potential of wind turbine blades
DEFF Research Database (Denmark)
2014-01-01
-twist coupling magnitude of up to 0.2 is feasible to achieve in the baseline blade structure made of glass-fiber reinforced plastics. Further, by substituting the glass-fibers with carbon-fibers the coupling effect can be increased to 0.4. Additionally, the effect of introduction of bend-twist coupling...
14. A twisted generalization of Novikov-Poisson algebras
OpenAIRE
Yau, Donald
2010-01-01
Hom-Novikov-Poisson algebras, which are twisted generalizations of Novikov-Poisson algebras, are studied. Hom-Novikov-Poisson algebras are shown to be closed under tensor products and several kinds of twistings. Necessary and sufficient conditions are given under which Hom-Novikov-Poisson algebras give rise to Hom-Poisson algebras.
15. Twisted Acceleration-Enlarged Newton-Hooke Hopf Algebras
International Nuclear Information System (INIS)
Daszkiewicz, M.
2010-01-01
Ten Abelian twist deformations of acceleration-enlarged Newton-Hooke Hopf algebra are considered. The corresponding quantum space-times are derived as well. It is demonstrated that their contraction limit τ → ∞ leads to the new twisted acceleration-enlarged Galilei spaces. (author)
16. Enhancement of heat transfer using varying width twisted tape inserts
African Journals Online (AJOL)
user
enhancement of heat transfer with twisted tape inserts as compared to plain ... studies for heat transfer and pressure drop of laminar flow in horizontal tubes ... flow in rectangular and square plain ducts and ducts with twisted-tape inserts .... presence of the insert in the pipe causes resistance to flow and increases turbulence.
17. Electronic and Optical Properties of Twisted Bilayer Graphene
Science.gov (United States)
Huang, Shengqiang
The ability to isolate single atomic layers of van der Waals materials has led to renewed interest in the electronic and optical properties of these materials as they can be fundamentally different at the monolayer limit. Moreover, these 2D crystals can be assembled together layer by layer, with controllable sequence and orientation, to form artificial materials that exhibit new features that are not found in monolayers nor bulk. Twisted bilayer graphene is one such prototype system formed by two monolayer graphene layers placed on top of each other with a twist angle between their lattices, whose electronic band structure depends on the twist angle. This thesis presents the efforts to explore the electronic and optical properties of twisted bilayer graphene by Raman spectroscopy and scanning tunneling microscopy measurements. We first synthesize twisted bilayer graphene with various twist angles via chemical vapor deposition. Using a combination of scanning tunneling microscopy and Raman spectroscopy, the twist angles are determined. The strength of the Raman G peak is sensitive to the electronic band structure of twisted bilayer graphene and therefore we use this peak to monitor changes upon doping. Our results demonstrate the ability to modify the electronic and optical properties of twisted bilayer graphene with doping. We also fabricate twisted bilayer graphene by controllable stacking of two graphene monolayers with a dry transfer technique. For twist angles smaller than one degree, many body interactions play an important role. It requires eight electrons per moire unit cell to fill up each band instead of four electrons in the case of a larger twist angle. For twist angles smaller than 0.4 degree, a network of domain walls separating AB and BA stacking regions forms, which are predicted to host topologically protected helical states. Using scanning tunneling microscopy and spectroscopy, these states are confirmed to appear on the domain walls when inversion
18. Duality and braiding in twisted quantum field theory
International Nuclear Information System (INIS)
Riccardi, Mauro; Szabo, Richard J.
2008-01-01
We re-examine various issues surrounding the definition of twisted quantum field theories on flat noncommutative spaces. We propose an interpretation based on nonlocal commutative field redefinitions which clarifies previously observed properties such as the formal equivalence of Green's functions in the noncommutative and commutative theories, causality, and the absence of UV/IR mixing. We use these fields to define the functional integral formulation of twisted quantum field theory. We exploit techniques from braided tensor algebra to argue that the twisted Fock space states of these free fields obey conventional statistics. We support our claims with a detailed analysis of the modifications induced in the presence of background magnetic fields, which induces additional twists by magnetic translation operators and alters the effective noncommutative geometry seen by the twisted quantum fields. When two such field theories are dual to one another, we demonstrate that only our braided physical states are covariant under the duality
19. Analysis list: Twist1 [Chip-atlas[Archive
Lifescience Database Archive (English)
Full Text Available Twist1 Embryo,Neural + mm9 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/target/Tw...ist1.1.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/target/Twist1.5.tsv http://dbarchive.biosciencedbc....jp/kyushu-u/mm9/target/Twist1.10.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/colo/Twist1.Embryo.tsv,http://dbarchive.bioscien...cedbc.jp/kyushu-u/mm9/colo/Twist1.Neural.tsv http://dbarchive.bioscience...dbc.jp/kyushu-u/mm9/colo/Embryo.gml,http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/colo/Neural.gml ...
20. On the performance analysis of Savonius rotor with twisted blades
Energy Technology Data Exchange (ETDEWEB)
Saha, U.K.; Rajkumar, M. Jaya [Department of Mechanical Engineering, Indian Institute of Technology Guwahati, Guwahati-781 039 (India)
2006-09-15
The present investigation is aimed at exploring the feasibility of twisted bladed Savonius rotor for power generation. The twisted blade in a three-bladed rotor system has been tested in a low speed wind tunnel, and its performance has been compared with conventional semicircular blades (with twist angle of 0{sup o}). Performance analysis has been made on the basis of starting characteristics, static torque and rotational speed. Experimental evidence shows the potential of the twisted bladed rotor in terms of smooth running, higher efficiency and self-starting capability as compared to that of the conventional bladed rotor. Further experiments have been conducted in the same setup to optimize the twist angle. (author)
1. Bianisotropic metamaterials based on twisted asymmetric crosses
International Nuclear Information System (INIS)
Reyes-Avendaño, J A; Sampedro, M P; Juárez-Ruiz, E; Pérez-Rodríguez, F
2014-01-01
The effective bianisotropic response of 3D periodic metal-dielectric structures, composed of crosses with asymmetrically-cut wires, is investigated within a general homogenization theory using the Fourier formalism and the form-factor division approach. It is found that the frequency dependence of the effective permittivity for a system of periodically-repeated layers of metal crosses exhibits two strong resonances, whose separation is due to the cross asymmetry. Besides, bianisotropic metamaterials, having a base of four twisted asymmetric crosses, are proposed. The designed metamaterials possess negative refractive index at frequencies determined by the cross asymmetry, the gap between the arms of adjacent crosses lying on the same plane, and the type of Bravais lattice. (papers)
2. Band engineering in twisted molybdenum disulfide bilayers
Science.gov (United States)
Zhao, Yipeng; Liao, Chengwei; Ouyang, Gang
2018-05-01
In order to explore the theoretical relationship between interlayer spacing, interaction and band offset at the atomic level in vertically stacked two-dimensional (2D) van der Waals (vdW) structures, we propose an analytical model to address the evolution of interlayer vdW coupling with random stacking configurations in MoS2 bilayers based on the atomic-bond-relaxation correlation mechanism. We found that interlayer spacing changes substantially with respect to the orientations, and the bandgap increases from 1.53 eV (AB stacking) to 1.68 eV (AA stacking). Our results reveal that the evolution of interlayer vdW coupling originates from the interlayer interaction, leading to interlayer separations and electronic properties changing with stacking configurations. Our predictions constitute a demonstration of twist engineering the band shift in the emergent class of 2D crystals, transition-metal dichalcogenides.
3. Unusual presentation of twisted ovarian cyst
Directory of Open Access Journals (Sweden)
Vineet V Mishra
2016-01-01
Full Text Available Ovarian torsion (also termed as adnexal torsion refers to partial or complete rotation of the ovary and a portion of fallopian tube along its supplying vascular pedicle. It occurs commonly in reproductive age group; more on the right side (60% and often presents with acute lower abdominal pain lasting for few hours and up to 24 h, accounting for 2.7% of acute gynecological conditions. It is one of the devastating conditions, hampering blood supply of ovary which may lead to total necrosis of ovarian tissue and complications, if not diagnosed and managed in time. Hence, we present a case on a twisted ovarian cyst in postmenopausal woman with unusual symptomatology leading to delayed diagnosis and loss of an ovary.
4. Regular non-twisting S-branes
International Nuclear Information System (INIS)
Obregon, Octavio; Quevedo, Hernando; Ryan, Michael P.
2004-01-01
We construct a family of time and angular dependent, regular S-brane solutions which corresponds to a simple analytical continuation of the Zipoy-Voorhees 4-dimensional vacuum spacetime. The solutions are asymptotically flat and turn out to be free of singularities without requiring a twist in space. They can be considered as the simplest non-singular generalization of the singular S0-brane solution. We analyze the properties of a representative of this family of solutions and show that it resembles to some extent the asymptotic properties of the regular Kerr S-brane. The R-symmetry corresponds, however, to the general lorentzian symmetry. Several generalizations of this regular solution are derived which include a charged S-brane and an additional dilatonic field. (author)
5. Dynamical twisted mass fermions and baryon spectroscopy
International Nuclear Information System (INIS)
Drach, V.
2010-06-01
The aim of this work is an ab initio computation of the baryon masses starting from quantum chromodynamics (QCD). This theory describes the interaction between quarks and gluons and has been established at high energy thanks to one of its fundamental properties: the asymptotic freedom. This property predicts that the running coupling constant tends to zero at high energy and thus that perturbative expansions in the coupling constant are justified in this regime. On the contrary the low energy dynamics can only be understood in terms of a non perturbative approach. To date, the only known method that allows the computation of observables in this regime together with a control of its systematic effects is called lattice QCD. It consists in formulating the theory on an Euclidean space-time and to evaluating numerically suitable functional integrals. First chapter is an introduction to the QCD in the continuum and on a discrete space time. The chapter 2 describes the formalism of maximally twisted fermions used in the European Twisted Mass (ETM) collaboration. The chapter 3 deals with the techniques needed to build hadronic correlator starting from gauge configuration. We then discuss how we determine hadron masses and their statistical errors. The numerical estimation of functional integral is explained in chapter 4. It is stressed that it requires sophisticated algorithm and massive parallel computing on Blue-Gene type architecture. Gauge configuration production is an important part of the work realized during my Ph.D. Chapter 5 is a critical review on chiral perturbation theory in the baryon sector. The two last chapter are devoted to the analysis in the light and strange baryon sector. Systematics and chiral extrapolation are extensively discussed. (author)
6. Bioinspired twisted composites based on Bouligand structures
Science.gov (United States)
Pinto, F.; Iervolino, O.; Scarselli, G.; Ginzburg, D.; Meo, M.
2016-04-01
The coupling between structural support and protection makes biological systems an important source of inspiration for the development of advanced smart composite structures. In particular, some particular material configurations can be implemented into traditional composites in order to improve their impact resistance and the out-of-plane properties, which represents one of the major weakness of commercial carbon fibres reinforced polymers (CFRP) structures. Based on this premise, a three-dimensional twisted arrangement shown in a vast multitude of biological systems (such as the armoured cuticles of Scarabei, the scales of Arapaima Gigas and the smashing club of Odontodactylus Scyllarus) has been replicated to develop an improved structural material characterised by a high level of in-plane isotropy and a higher interfacial strength generated by the smooth stiffness transition between each layer of fibrils. Indeed, due to their intrinsic layered nature, interlaminar stresses are one of the major causes of failure of traditional CFRP and are generated by the mismatch of the elastic properties between plies in a traditional laminate. Since the energy required to open a crack or a delamination between two adjacent plies is due to the difference between their orientations, the gradual angle variation obtained by mimicking the Bouligand Structures could improve energy absorption and the residual properties of carbon laminates when they are subjected to low velocity impact event. Two different bioinspired laminates were manufactured following a double helicoidal approach and a rotational one and were subjected to a complete test campaign including low velocity impact loading and compared to a traditional quasi-isotropic panel. Fractography analysis via X-Ray tomography was used to understand the mechanical behaviour of the different laminates and the residual properties were evaluated via Compression After Impact (CAI) tests. Results confirmed that the biological
7. Help Protect Babies from Whooping Cough
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... this? Submit What's this? Submit Button Past Emails Help Protect Babies from Whooping Cough Language: English (US) ... Emails Language: English (US) Español (Spanish) File Formats Help: How do I view different file formats (PDF, ...
8. Having a Baby (Especially for Teens)
Science.gov (United States)
... pregnancy. Caffeine—Caffeine is found in coffee, tea, chocolate, energy drinks, and soft drinks. It is a ... only for a few weeks or months has health benefits for the baby. When you go back to ...
9. Common Cold in Babies: Symptoms and Causes
Science.gov (United States)
... clear at first but might thicken and turn yellow or green Other signs and symptoms of a common cold in a baby may include: Fever Sneezing Coughing Decreased appetite Irritability Difficulty sleeping Trouble ...
10. Surrogate Motherhood II: Reflections after "Baby M."
Science.gov (United States)
Schwartz, Lita Linzer
1988-01-01
Discusses the "Baby M" surrogate motherhood case which has produced heated debate in popular media, legal publications, and other professional journals. Summarizes arguments offered and reasoning behind actions of judiciary. (Author/ABL)
11. Zika Virus: Protecting Pregnant Women and Babies
Science.gov (United States)
... Digital Press Kit Read the MMWR Science Clips Zika Virus Protecting Pregnant Women and Babies Language: English (US) ... Spanish) Recommend on Facebook Tweet Share Compartir Overview Zika virus infection (Zika) during pregnancy can cause damage to ...
12. A report from America: Baby M.
Science.gov (United States)
Rachels, James
1987-10-01
Rachels reviews the social and legal facts of the celebrated "Baby M" case, in which surrogate Mary Beth Whitehead attempted to keep the daughter she had borne under contract to William Stern. The first phase of the legal battle between the parents ended in March 1988, when New Jersey Superior Court Judge Harvey R. Sorkow upheld the validity of the surrogacy contract, terminated Whitehead's parental rights, and awarded custody of the child to Stern. Rachels comments on public reaction to "Baby M," on Sorkow's decision, and on the impact the case may have on legislative attempts to regulate surrogacy. He also uses the example of "Baby M," as well as that of California heart transplant patient "Baby Jesse," to discuss how the media sensationalize controversial issues.
13. Why lions roar like babies cry
Science.gov (United States)
Titze, Ingo
2012-11-01
When an angry lion roars, the sounds it emits can terrify anyone within earshot. But, as Ingo Titze explains, the properties of a lion's roar have some surprising similarities with those of a crying baby.
14. Quantum cosmology and baby universes
International Nuclear Information System (INIS)
Grishchuk, L.P.
1990-01-01
The contributed papers presented to the workshop on ''Quantum Cosmology and Baby Universes'' have demonstrated the great interest in, and rapid development of, the field of quantum cosmology. In my view, there are at least three areas of active research at present. The first area can be defined as that of practical calculations. Here researchers are dealing with the basic quantum cosmological equation, which is the Wheeler-DeWitt equation. They try to classify all possible solutions to the Wheeler-DeWitt equation or seek a specific integration contour in order to select one particular wave function or generalize the simple minisuperspace models to more complicated cases, including various inhomogeneities, anisotropies, etc. The second area of research deals with the interpretational issues of quantum cosmology. There are still many questions about how to extract the observational consequences from a given cosmological wave function, the role of time in quantum cosmology, and how to reformulate the rules of quantum mechanics in such a way that they could be applicable to the single system which is our Universe. The third area of research is concerned with the so-called ''third quantization'' of gravity. In this approach a wave function satisfying the Wheeler-DeWitt equation becomes an operator acting on a Wave Function of the many-universes system. Within this approach one operates with Euclidean worm-holes joining different Lorentzian universes. (author)
15. PIXE analysis by baby cyclotron
International Nuclear Information System (INIS)
Yoshida, Hyogo; Tanaka, Teruaki; Ito, Takashi; Toda, Yohjiro; Wakasa, Hideichiro
1988-01-01
The Japan Steel Works, Ltd. has been supplying a very small sized cyclotron (Baby Cyclotron) to hospitals and research facilities. The cyclotron is designed to produce short-lived radioisotopes for medical use. In the present study, this cyclotron is modified so that it can serve for PIXE analysis. The PIXE (particle induced X-ray emission) technique has the following features: (1) Down to 1 ng of trace material in a sample (mg - μg) can be detected, (2) An analysis run is completed in one to ten minutes, permitting economical analysis for a large number of samples, (3) Several elements can be analyzed simultaneously, with an almost constant sensitivity for a variety of elements ranging from aluminum to heavy metals, (4) Analysis can be performed nondestructively without a chemical process, and (5) The use of microbeam can provide data on the distribution of elements with a resolution of several μm. Software for analysis is developed to allow the modified equipment to perform peak search, background fitting, and identification and determination of peaks. A study is now being conducted to examine the performance of the equipment for PIXE analysis of thin samples. Satisfactory results have been obtained. The analysis time, excluding the background correction, is 5-10 min. (Nogami, K.)
16. The ART of marketing babies.
Science.gov (United States)
2010-01-01
New legislation can be oppressive for a significant population depending upon the politics of its drafters. The current upsurge of the surrogacy trade in India, and the label of a "win-win" situation that it has acquired, points towards an unfettered commercialisation of assisted reproductive technology and the practice of surrogacy that is blinding its middle class users as well as providers, policy makers and law makers, and charging an imagination that is already caught up in spiralling consumerism. This paper analyses the Draft Assisted Reproductive Technology (Regulation) Bill and Rules, 2008, in the Indian socioeconomic context. It identifies the interests of the affected women, and examines the contradictions of the proposed Bill with their interests, as well as with current health and population policies, confining itself to the handling of surrogacy and not the entire content of the Bill. The bases of the analytical perspective used are: the context of poverty and the health needs of the Indian population; the need to locate surrogacy services within the overall public health service context and its epidemiological basis; the need to restrain direct human experimentation for the advancement of any technology; the use of safer methods; and, finally, the rights of surrogate mothers and their babies, in India, as opposed to the compulsion or dynamics of the medical market and reproductive tourism.
17. Twisted boundary states in c=1 coset conformal field theories
International Nuclear Information System (INIS)
Ishikawa, Hiroshi; Yamaguchi, Atsushi
2003-01-01
We study the mutual consistency of twisted boundary conditions in the coset conformal field theory G/H. We calculate the overlap of the twisted boundary states of G/H with the untwisted ones, and show that the twisted boundary states are consistently defined in the charge-conjugation modular invariant. The overlap of the twisted boundary states is expressed by the branching functions of a twisted affine Lie algebra. As a check of our argument, we study the diagonal coset theory so(2n) 1 +so(2n) 1 /so(2n) 2 , which is equivalent to the orbifold S 1 /Z 2 at a particular radius. We construct the boundary states twisted by the automorphisms of the unextended Dynkin diagram of so(2n), and show their mutual consistency by identifying their counterpart in the orbifold. For the triality of so(8), the twisted states of the coset theory correspond to neither the Neumann nor the Dirichlet boundary states of the orbifold and yield conformal boundary states that preserve only the Virasoro algebra. (author)
18. Conical twist fields and null polygonal Wilson loops
Science.gov (United States)
Castro-Alvaredo, Olalla A.; Doyon, Benjamin; Fioravanti, Davide
2018-06-01
Using an extension of the concept of twist field in QFT to space-time (external) symmetries, we study conical twist fields in two-dimensional integrable QFT. These create conical singularities of arbitrary excess angle. We show that, upon appropriate identification between the excess angle and the number of sheets, they have the same conformal dimension as branch-point twist fields commonly used to represent partition functions on Riemann surfaces, and that both fields have closely related form factors. However, we show that conical twist fields are truly different from branch-point twist fields. They generate different operator product expansions (short distance expansions) and form factor expansions (large distance expansions). In fact, we verify in free field theories, by re-summing form factors, that the conical twist fields operator product expansions are correctly reproduced. We propose that conical twist fields are the correct fields in order to understand null polygonal Wilson loops/gluon scattering amplitudes of planar maximally supersymmetric Yang-Mills theory.
19. Safe Sleep for Babies PSA (:60)
Centers for Disease Control (CDC) Podcasts
2018-01-09
This 60 second public service announcement is based on the January 2018 CDC Vital Signs report. Every year, there are about 3,500 sleep-related deaths among U.S. babies. Learn how to create a safe sleep environment for babies. Created: 1/9/2018 by Centers for Disease Control and Prevention (CDC). Date Released: 1/9/2018.
20. Baby boomers nearing retirement: the healthiest generation?
Science.gov (United States)
Rice, Neil E; Lang, Iain A; Henley, William; Melzer, David
2010-02-01
The baby-boom generation is entering retirement. Having experienced unprecedented prosperity and improved medical technology, they should be the healthiest generation ever. We compared prevalence of disease and risk factors at ages 50-61 years in baby boomers with the preceding generation and attributed differences to period or cohort effects. Data were from the Health Survey for England (HSE) from 1994 to 2007 (n = 48,563). Logistic regression models compared health status between birth cohorts. Age-period-cohort models identified cohort and period effects separately. Compared to the wartime generation, the baby-boomer group was heavier (3.02 kg; 95% confidence interval [CI], 2.42-3.63; p Baby boomers reported fewer heart attacks (OR = 0.61; CI, 0.47-0.79; p baby boomers are moving toward retirement with improved cardiovascular health. However, the baby-boomer cohort has a higher prevalence of mental illness diagnoses and shows no improvement in self-rated health compared to the wartime birth cohort. There remains substantial scope to reduce health risks and future disability.
1. 75 FR 81788 - Revocation of Requirements for Full-Size Baby Cribs and Non-Full-Size Baby Cribs
Science.gov (United States)
2010-12-28
...-Size Baby Cribs and Non-Full- Size Baby Cribs AGENCY: Consumer Product Safety Commission. ACTION: Final... Safety Specification for Full-Size Baby Cribs,'' and ASTM F 406-10a, Standard Consumer Safety Specification for Non-Full-Size Baby Cribs/Play Yards.'' The crib standards that the CPSC is publishing...
2. 75 FR 43107 - Revocation of Requirements for Full-Size Baby Cribs and Non-Full-Size Baby Cribs
Science.gov (United States)
2010-07-23
...] Revocation of Requirements for Full-Size Baby Cribs and Non-Full- Size Baby Cribs AGENCY: Consumer Product... standards, and include ASTM F 1169-10, Standard Consumer Safety Specification for Full-Size Baby Cribs,'' and ASTM F 406-10, Standard Consumer Safety Specification for Non-Full-Size Baby Cribs/Play Yards...
3. Conformal invariance and pion wave functions of nonleading twist
International Nuclear Information System (INIS)
Braun, V.M.; Filyanov, I.E.
1989-01-01
The restrictions are studied for the general structure of pion wave functions of twist 3 and twist 4 imposed by the conformal symmetry and the equations of motion. A systematic expansion of wave functions in the conformal spin is built and the first order corrections to asymptotic formulae are calculated by the QCD sum rule method. In particular, we have found a multiplicatively renormalizable contribution into the two-particle wave function of twist 4 which cannot be expanded in a finite set of Gegenbauer polynomials. 19 refs.; 5 figs
4. Quantum communication through a spin ring with twisted boundary conditions
International Nuclear Information System (INIS)
Bose, S.; Jin, B.-Q.; Korepin, V.E.
2005-01-01
We investigate quantum communication between the sites of a spin ring with twisted boundary conditions. Such boundary conditions can be achieved by a magnetic flux through the ring. We find that a nonzero twist can improve communication through finite odd-numbered rings and enable high-fidelity multiparty quantum communication through spin rings (working near perfectly for rings of five and seven spins). We show that in certain cases, the twist results in the complete blockage of quantum-information flow to a certain site of the ring. This effect can be exploited to interface and entangle a flux qubit and a spin qubit without embedding the latter in a magnetic field
5. TWIST1 promotes invasion through mesenchymal change in human glioblastoma
Directory of Open Access Journals (Sweden)
Wakimoto Hiroaki
2010-07-01
Full Text Available Abstract Background Tumor cell invasion into adjacent normal brain is a mesenchymal feature of GBM and a major factor contributing to their dismal outcomes. Therefore, better understandings of mechanisms that promote mesenchymal change in GBM are of great clinical importance to address invasion. We previously showed that the bHLH transcription factor TWIST1 which orchestrates carcinoma metastasis through an epithelial mesenchymal transition (EMT is upregulated in GBM and promotes invasion of the SF767 GBM cell line in vitro. Results To further define TWIST1 functions in GBM we tested the impact of TWIST1 over-expression on invasion in vivo and its impact on gene expression. We found that TWIST1 significantly increased SNB19 and T98G cell line invasion in orthotopic xenotransplants and increased expression of genes in functional categories associated with adhesion, extracellular matrix proteins, cell motility and locomotion, cell migration and actin cytoskeleton organization. Consistent with this TWIST1 reduced cell aggregation, promoted actin cytoskeletal re-organization and enhanced migration and adhesion to fibronectin substrates. Individual genes upregulated by TWIST1 known to promote EMT and/or GBM invasion included SNAI2, MMP2, HGF, FAP and FN1. Distinct from carcinoma EMT, TWIST1 did not generate an E- to N-cadherin "switch" in GBM cell lines. The clinical relevance of putative TWIST target genes SNAI2 and fibroblast activation protein alpha (FAP identified in vitro was confirmed by their highly correlated expression with TWIST1 in 39 human tumors. The potential therapeutic importance of inhibiting TWIST1 was also shown through a decrease in cell invasion in vitro and growth of GBM stem cells. Conclusions Together these studies demonstrated that TWIST1 enhances GBM invasion in concert with mesenchymal change not involving the canonical cadherin switch of carcinoma EMT. Given the recent recognition that mesenchymal change in GBMs is
6. Baby boom generation at the retirement onset
Directory of Open Access Journals (Sweden)
Stojilković Jelena
2010-01-01
Full Text Available Sudden increase in the number of live births after the Second World War due to an increase in fertility rates has led to the formation of cohorts with specific characteristics or baby boom generation. This generation is unique in the history of the demographic phenomenon that has affected and affects the functioning of many segments of society. The aim of this paper is to assess structure of baby boomers who are few years away from retirement, using demographic data. Impact of baby boomer age structure of current and future retirees is described with a graphical display of current and projected age pyramid of baby boomers. Demographic pattern that women live longer than men is evident in the projected pyramid. In addition, the number of baby boomers will lead to a "younger" old population. The imbalance in the number of men and women pensioners, as well as older cohorts of women and female baby boomers was analyzed. As a result, an increasing trend of women's age pensioners who are members of the baby boom generation was clearly observed, which is opposite to the older cohort of women who often were family pensioners. Different circumstances and conditions in which female boomers lived and worked will form a new "pension model" because they will gain their benefits as well as men, for the first time in significant number, unlike their mothers, which gained the right to retire after they become widows. Number of women age pensioners is getting greater comparing to men, as the result of changes in the economic activities of women in the last half of the 20th century. When baby boomers retire and exit the working population, this will create a vacuum, because the numerically smaller generations will enter working population, while the sudden and very shortly, the number of population older than 60 or 65 will increase, most of them will likely to acquire the right to a pension. It is undeniable that baby boomers had impact on demographic structure
7. Renormalization of quark propagator, vertex functions, and twist-2 operators from twisted-mass lattice QCD at Nf=4
Science.gov (United States)
Blossier, Benoît.; Brinet, Mariane; Guichon, Pierre; Morénas, Vincent; Pène, Olivier; Rodríguez-Quintero, Jose; Zafeiropoulos, Savvas
2015-06-01
We present a precise nonperturbative determination of the renormalization constants in the mass independent RI'-MOM scheme. The lattice implementation uses the Iwasaki gauge action and four degenerate dynamical twisted-mass fermions. The gauge configurations are provided by the ETM Collaboration. Renormalization constants for scalar, pseudoscalar, vector and axial operators, as well as the quark propagator renormalization, are computed at three different values of the lattice spacing, two volumes and several twisted-mass parameters. The method we developed allows for a precise cross-check of the running, thanks to the particular proper treatment of hypercubic artifacts. Results for the twist-2 operator O44 are also presented.
8. 7 CFR 319.56-43 - Baby corn and baby carrots from Zambia.
Science.gov (United States)
2010-01-01
... § 319.56-43 Baby corn and baby carrots from Zambia. (a) Immature, dehusked “baby” sweet corn (Zea mays L... consignments only. (b) Immature “baby” carrots (Daucus carota L. ssp. sativus) for consumption measuring 10 to...
9. What is my Baby Like? Representations Concerning the Baby in the Third Trimester of Pregnancy
Directory of Open Access Journals (Sweden)
Marta Pedreira
2015-11-01
Full Text Available AimTo investigate if during the third trimester of pregnancy fantasies emerge in the baby representations based on the information that pregnant women have on their real babies through ultrasound techniques.MethodA qualitative, descriptive and exploratory research based on a sample of 30 pregnant Portuguese women, whose average age is 32 years old, was developed. A socio-demographic questionnaire and a semi-directive interview entitled "Interview of Maternal Representations During Pregnancy – Revised Version" (IRMAG-R, Ammaniti & Tambelli, 2010 were employed.ResultsBaby representations are immersed in a fantasy dimension, which means that the imaginary baby is quite present in this phase of pregnancy. Pregnant women mainly attribute psychological characteristics to the babies, rather than physical characteristics. Regardless of the type of characteristics analysed, the preference for these characteristics emerges based on their wishes. Secondly, characteristics of the parents may also emerge. Fetal movements and information from ultrasound have no significant influence on the characterization of the baby.ConclusionDespite the development of ultrasound techniques, the imaginary baby defines parents representations about the baby on the third trimester of pregnancy. Consequently, a new understanding of how pregnant women experience the transition to the postnatal phase has to be considered.
10. Enhancement of heat transfer using varying width twisted tape inserts
African Journals Online (AJOL)
International Journal of Engineering, Science and Technology ... experimental investigations of the augmentation of turbulent flow heat transfer in a horizontal tube by means of varying width twisted tape inserts with air as the working fluid.
11. Periodic solutions of asymptotically linear Hamiltonian systems without twist conditions
Energy Technology Data Exchange (ETDEWEB)
Cheng Rong [Coll. of Mathematics and Physics, Nanjing Univ. of Information Science and Tech., Nanjing (China); Dept. of Mathematics, Southeast Univ., Nanjing (China); Zhang Dongfeng [Dept. of Mathematics, Southeast Univ., Nanjing (China)
2010-05-15
In dynamical system theory, especially in many fields of applications from mechanics, Hamiltonian systems play an important role, since many related equations in mechanics can be written in an Hamiltonian form. In this paper, we study the existence of periodic solutions for a class of Hamiltonian systems. By applying the Galerkin approximation method together with a result of critical point theory, we establish the existence of periodic solutions of asymptotically linear Hamiltonian systems without twist conditions. Twist conditions play crucial roles in the study of periodic solutions for asymptotically linear Hamiltonian systems. The lack of twist conditions brings some difficulty to the study. To the authors' knowledge, very little is known about the case, where twist conditions do not hold. (orig.)
12. The geometric Langlands twist in five and six dimensions
International Nuclear Information System (INIS)
Bak, Dongsu; Gustavsson, Andreas
2015-01-01
Abelian 6d (2,0) theory has SO(5) R symmetry. We twist this theory by identifying the R symmetry group with the SO(5) subgroup of the SO(1,5) Lorentz group. This twisted theory can be put on any five-manifold M, times R, while preserving one scalar supercharge. We subsequently assume the existence of one unit normalized Killing vector field on M, and we find a corresponding SO(4) twist that preserves two supercharges and is a generalization of the geometric Langlands twist of 4d SYM. We generalize the story to non-Abelian gauge group for the corresponding 5d SYM theories on M. We derive a vanishing theorem for BPS contact instantons by identifying the 6d potential energy and its BPS bound, in the 5d theory. To this end we need to perform a Wick rotation that complexifies the gauge field.
13. Static-light meson masses from twisted mass lattice QCD
International Nuclear Information System (INIS)
Jansen, Karl; Michael, Chris; Shindler, Andrea; Wagner, Marc
2008-08-01
We compute the static-light meson spectrum using two-flavor Wilson twisted mass lattice QCD. We have considered five different values for the light quark mass corresponding to 300 MeV PS S mesons. (orig.)
14. Higher-Twist Dynamics in Large Transverse Momentum Hadron Production
International Nuclear Information System (INIS)
Francois, Alero
2009-01-01
A scaling law analysis of the world data on inclusive large-p # perpendicular# hadron production in hadronic collisions is carried out. A significant deviation from leading-twist perturbative QCD predictions at next-to-leading order is reported. The observed discrepancy is largest at high values of x # perpendicular# = 2p # perpendicular#/√s. In contrast, the production of prompt photons and jets exhibits the scaling behavior which is close to the conformal limit, in agreement with the leading-twist expectation. These results bring evidence for a non-negligible contribution of higher-twist processes in large-p # perpendicular# hadron production in hadronic collisions, where the hadron is produced directly in the hard subprocess rather than by gluon or quark jet fragmentation. Predictions for scaling exponents at RHIC and LHC are given, and it is suggested to trigger the isolated large-p # perpendicular# hadron production to enhance higher-twist processes.
15. Flux Density through Guides with Microstructured Twisted Clad DB Medium
Directory of Open Access Journals (Sweden)
M. A. Baqir
2014-01-01
Full Text Available The paper deals with the study of flux density through a newly proposed twisted clad guide containing DB medium. The inner core and the outer clad sections are usual dielectrics, and the introduced twisted windings at the core-clad interface are treated under DB boundary conditions. The pitch angle of twist is supposed to greatly contribute towards the control over the dispersion characteristics of the guide. The eigenvalue equation for the guiding structure is deduced, and the analytical investigations are made to explore the propagation patterns of flux densities corresponding to the sustained low-order hybrid modes under the situation of varying pitch angles. The emphasis has been put on the effects due to the DB twisted pitch on the propagation of energy flux density through the guide.
16. Õnnetu saatusega Oliver Twist Polanski meelevallas / Andres Laasik
Index Scriptorium Estoniae
Laasik, Andres, 1960-2016
2005-01-01
Mängufilm Charles Dickensi romaani järgi "Oliver Twist" : stsenarist Ronald Harwood : režissöör Roman Polanski : nimiosas Barney Clark, Fagin - Ben Kingsley : Suurbritannia - Tšehhi - Prantsusmaa - Itaalia 2005
17. Study of twist boundaries in aluminium. Structure and intergranular diffusion
International Nuclear Information System (INIS)
Lemuet, Daniel
1981-01-01
This research thesis addresses the study of grain boundaries in oriented crystals, and more particularly the systematic calculation of intergranular structures and energies of twist boundaries of <001> axis in aluminium, the determination of intergranular diffusion coefficients of zinc in a set of twist bi-crystals of same axis encompassing a whole range of disorientations, and the search for a correlation between these experimental results and calculated structures
18. 'Twisted' strings and higher level Kac-Moody representations
International Nuclear Information System (INIS)
Horvath, Z.; Palla, L.
1989-01-01
Using an orbifold-like construction the twisted sector of a closed string moving on GxG (with G simply laced) is determined. A level-two G current operating there is constructed explicitly. The decomposition of the twisted sector into products between appropriate conformal and level-two G representations is given if 2 rank G-2 dim G/(2+g)<1. (orig.)
19. New look at the dynamics of twisted accretion disks
International Nuclear Information System (INIS)
Hatchett, S.P.; Begelman, M.C.; Sarazin, C.L.
1981-01-01
We reexamine the dynamic response of a thin, accretion disk to twisting torques, guided by the earlier analyses by Bardeen and Petterson. We make several corrections to this earlier work, and present a new version of the twist equations consistent with their physical assumptions. By describing the distortion of the disk in terms Cartesian direction cosines rather than the Euler angles used by the earlier authors, we are able to transform the twist equations from a pair of coupled, nonlinear, partial differential equations to a single, linear, complex one. We write down formulae for the external twisting torques likley to be encountered in astrophysic, and we show that even with these driving torques our twist equation remains linear. We find exact, analytic solutions for steady state structure of a disk subject to Lense-Thirring torques by a nonaligned central Kerr black hole and also for the time-dependent problem of the structure of a slaved disk with its oscillating boundary conditions. Finally, we discuss the stability of disks against twisting modes and show that undriven disks and disks subject to time-independent driving torques are stable
20. Observations on discretization errors in twisted-mass lattice QCD
International Nuclear Information System (INIS)
Sharpe, Stephen R.
2005-01-01
I make a number of observations concerning discretization errors in twisted-mass lattice QCD that can be deduced by applying chiral perturbation theory including lattice artifacts. (1) The line along which the partially conserved axial current quark mass vanishes in the untwisted-mass-twisted-mass plane makes an angle to the twisted-mass axis which is a direct measure of O(a) terms in the chiral Lagrangian, and is found numerically to be large; (2) Numerical results for pionic quantities in the mass plane show the qualitative properties predicted by chiral perturbation theory, in particular, an asymmetry in slopes between positive and negative untwisted quark masses; (3) By extending the description of the 'Aoki regime' (where m q ∼a 2 Λ QCD 3 ) to next-to-leading order in chiral perturbation theory I show how the phase-transition lines and lines of maximal twist (using different definitions) extend into this region, and give predictions for the functional form of pionic quantities; (4) I argue that the recent claim that lattice artifacts at maximal twist have apparent infrared singularities in the chiral limit results from expanding about the incorrect vacuum state. Shifting to the correct vacuum (as can be done using chiral perturbation theory) the apparent singularities are summed into nonsingular, and furthermore predicted, forms. I further argue that there is no breakdown in the Symanzik expansion in powers of lattice spacing, and no barrier to simulating at maximal twist in the Aoki regime
1. Twisting short dsDNA with applied tension
Science.gov (United States)
Zoli, Marco
2018-02-01
The twisting deformation of mechanically stretched DNA molecules is studied by a coarse grained Hamiltonian model incorporating the fundamental interactions that stabilize the double helix and accounting for the radial and angular base pair fluctuations. The latter are all the more important at short length scales in which DNA fragments maintain an intrinsic flexibility. The presented computational method simulates a broad ensemble of possible molecule conformations characterized by a specific average twist and determines the energetically most convenient helical twist by free energy minimization. As this is done for any external load, the method yields the characteristic twist-stretch profile of the molecule and also computes the changes in the macroscopic helix parameters i.e. average diameter and rise distance. It is predicted that short molecules under stretching should first over-twist and then untwist by increasing the external load. Moreover, applying a constant load and simulating a torsional strain which over-twists the helix, it is found that the average helix diameter shrinks while the molecule elongates, in agreement with the experimental trend observed in kilo-base long sequences. The quantitative relation between percent relative elongation and superhelical density at fixed load is derived. The proposed theoretical model and computational method offer a general approach to characterize specific DNA fragments and predict their macroscopic elastic response as a function of the effective potential parameters of the mesoscopic Hamiltonian.
2. Scanning tunneling microscopy and spectroscopy of twisted trilayer graphene
Science.gov (United States)
Zuo, Wei-Jie; Qiao, Jia-Bin; Ma, Dong-Lin; Yin, Long-Jing; Sun, Gan; Zhang, Jun-Yang; Guan, Li-Yang; He, Lin
2018-01-01
Twist, as a simple and unique degree of freedom, could lead to enormous novel quantum phenomena in bilayer graphene. A small rotation angle introduces low-energy van Hove singularities (VHSs) approaching the Fermi level, which result in unusual correlated states in the bilayer graphene. It is reasonable to expect that the twist could also affect the electronic properties of few-layer graphene dramatically. However, such an issue has remained experimentally elusive. Here, by using scanning tunneling microscopy/spectroscopy (STM/STS), we systematically studied a twisted trilayer graphene (TTG) with two different small twist angles between adjacent layers. Two sets of VHSs, originating from the two twist angles, were observed in the TTG, indicating that the TTG could be simply regarded as a combination of two different twisted bilayers of graphene. By using high-resolution STS, we observed a split of the VHSs and directly imaged the spatial symmetry breaking of electronic states around the VHSs. These results suggest that electron-electron interactions play an important role in affecting the electronic properties of graphene systems with low-energy VHSs.
3. Neutron radiography by using JSW baby cyclotron
International Nuclear Information System (INIS)
Toda, Yojiro
1995-01-01
4. Phthalates in baby skin care products.
Science.gov (United States)
Lampel, Heather P; Jacob, Sharon E
2011-01-01
The systemic toxicity of phthalates has been extensively reported. Although rarely sensitizing, phthalates have been implicated in promoting the development of both atopy and contact dermatitis in animal models. Dermal absorption of phthalates may contribute to overall chemical burden. Infants may be particularly susceptible to chemical exposures. Baby skin care products may be a significant source of phthalate exposure. We measured the phthalate content of 30 skin care products intended for babies and children. Nineteen leave-on and 11 wash-off baby skin care products were analyzed for 17 unique phthalates by an independent laboratory using standard gas chromatographic mass spectrometry. Of 30 products tested, four had phthalate levels above the reporting limit (0.1-0.5 ppm); of these, only one had levels above 1 ppm (44 ppm). There was no statistical significance of phthalate detection in leave-on versus wash-off products (p = .578). The majority (26 of 30) of the baby skin care products analyzed did not have detectable phthalate levels. Four products had detectable phthalate levels. In baby skin care products, levels of the 17 phthalates tested are low overall, but occasional products may contain higher phthalate levels. Monitoring products to ensure safety standards are met may be warranted.
5. Baby factories taint surrogacy in Nigeria.
Science.gov (United States)
Makinde, Olusesan Ayodeji; Makinde, Olufunmbi Olukemi; Olaleye, Olalekan; Brown, Brandon; Odimegwu, Clifford O
2016-01-01
The practice of reproductive medicine in Nigeria is facing new challenges with the proliferation of 'baby factories'. Baby factories are buildings, hospitals or orphanages that have been converted into places for young girls and women to give birth to children for sale on the black market, often to infertile couples, or into trafficking rings. This practice illegally provides outcomes (children) similar to surrogacy. While surrogacy has not been well accepted in this environment, the proliferation of baby factories further threatens its acceptance. The involvement of medical and allied health workers in the operation of baby factories raises ethical concerns. The lack of a properly defined legal framework and code of practice for surrogacy makes it difficult to prosecute baby factory owners, especially when they are health workers claiming to be providing services to clients. In this environment, surrogacy and other assisted reproductive techniques urgently require regulation in order to define when ethico-legal lines have been crossed in providing surrogacy or surrogacy-like services. Copyright © 2015 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.
6. Flux compactifications, twisted tori and doubled geometry
International Nuclear Information System (INIS)
Reid-Edwards, R.A.
2009-01-01
In [1] an O(D,D)-covariant sigma model describing the embedding of a closed world-sheet into the 2D-dimensional twisted torus X was proposed. Such sigma models provide a universal description of string theory with target spaces related by the action of T-duality. In this article a six-dimensional toy example is studied in detail. Different polarisations of the six-dimensional target space give different three-dimensional string backgrounds including a nilmanifold with H-flux, a T-fold with R-flux and a new class of T-folds. Global issues and connections with the doubled torus formalism are discussed. Finally, the sigma model introduced in [1], describing the embedding of a world-sheet into X, is generalised to one describing a target space which is a bundle of X over a base M d , allowing for a more complete description of the associated gauged supergravity from the world-sheet perspective to be given.
7. Twisted conformal field theories and Morita equivalence
Energy Technology Data Exchange (ETDEWEB)
Marotta, Vincenzo [Dipartimento di Scienze Fisiche, Universita di Napoli ' Federico II' and INFN, Sezione di Napoli, Compl. universitario M. Sant' Angelo, Via Cinthia, 80126 Napoli (Italy); Naddeo, Adele [CNISM, Unita di Ricerca di Salerno and Dipartimento di Fisica ' E.R. Caianiello' , Universita degli Studi di Salerno, Via Salvador Allende, 84081 Baronissi (Italy); Dipartimento di Scienze Fisiche, Universita di Napoli ' Federico II' , Compl. universitario M. Sant' Angelo, Via Cinthia, 80126 Napoli (Italy)], E-mail: adelenaddeo@yahoo.it
2009-04-01
The Morita equivalence for field theories on noncommutative two-tori is analysed in detail for rational values of the noncommutativity parameter {theta} (in appropriate units): an isomorphism is established between an Abelian noncommutative field theory (NCFT) and a non-Abelian theory of twisted fields on ordinary space. We focus on a particular conformal field theory (CFT), the one obtained by means of the m-reduction procedure [V. Marotta, J. Phys. A 26 (1993) 3481; V. Marotta, Mod. Phys. Lett. A 13 (1998) 853; V. Marotta, Nucl. Phys. B 527 (1998) 717; V. Marotta, A. Sciarrino, Mod. Phys. Lett. A 13 (1998) 2863], and show that it is the Morita equivalent of a NCFT. Finally, the whole m-reduction procedure is shown to be the image in the ordinary space of the Morita duality. An application to the physics of a quantum Hall fluid at Jain fillings {nu}=m/(2pm+1) is explicitly discussed in order to further elucidate such a correspondence and to clarify its role in the physics of strongly correlated systems. A new picture emerges, which is very different from the existing relationships between noncommutativity and many body systems [A.P. Polychronakos, arXiv: 0706.1095].
8. How the embryonic chick brain twists.
Science.gov (United States)
Chen, Zi; Guo, Qiaohang; Dai, Eric; Forsch, Nickolas; Taber, Larry A
2016-11-01
During early development, the tubular embryonic chick brain undergoes a combination of progressive ventral bending and rightward torsion, one of the earliest organ-level left-right asymmetry events in development. Existing evidence suggests that bending is caused by differential growth, but the mechanism for the predominantly rightward torsion of the embryonic brain tube remains poorly understood. Here, we show through a combination of in vitro experiments, a physical model of the embryonic morphology and mechanics analysis that the vitelline membrane (VM) exerts an external load on the brain that drives torsion. Our theoretical analysis showed that the force is of the order of 10 micronewtons. We also designed an experiment to use fluid surface tension to replace the mechanical role of the VM, and the estimated magnitude of the force owing to surface tension was shown to be consistent with the above theoretical analysis. We further discovered that the asymmetry of the looping heart determines the chirality of the twisted brain via physical mechanisms, demonstrating the mechanical transfer of left-right asymmetry between organs. Our experiments also implied that brain flexure is a necessary condition for torsion. Our work clarifies the mechanical origin of torsion and the development of left-right asymmetry in the early embryonic brain. © 2016 The Author(s).
9. Complex Toda theories and twisted reality conditions
International Nuclear Information System (INIS)
Evans, J.M.
1993-01-01
The Toda equations (based on a finite-dimensional or affine Lie algebra of superalgebra) are discussed as integrable non-linear differential equations for a set of complex scalar fields. We show that such complex Toda fields can either be restricted to take real values in the standard way or else they can be subjected to a 'twisted' reality condition associated to any Z 2 symmetry of the Cartan matrix or Dynkin diagram of the underlying algebra. Different reality conditions give rise to different lagrangian field theories. In the conformal case, however, these theories have the same central charge, while in the affine case they have the same mass spectrum. The construction of N=2 superconformal theories based on the superalgebras A(n, n-1) is clarified, and a new class of conformal field theories with positive kinetic energy based on the superalgebras C(n) is presented. The ideas developed are also relevant to understanding solition solutions in affine Toda theories with imaginary coupling constant. (orig.)
10. The Latest Twists in Chromatin Remodeling.
Science.gov (United States)
Blossey, Ralf; Schiessel, Helmut
2018-01-05
In its most restrictive interpretation, the notion of chromatin remodeling refers to the action of chromatin-remodeling enzymes on nucleosomes with the aim of displacing and removing them from the chromatin fiber (the effective polymer formed by a DNA molecule and proteins). This local modification of the fiber structure can have consequences for the initiation and repression of the transcription process, and when the remodeling process spreads along the fiber, it also results in long-range effects essential for fiber condensation. There are three regulatory levels of relevance that can be distinguished for this process: the intrinsic sequence preference of the histone octamer, which rules the positioning of the nucleosome along the DNA, notably in relation to the genetic information coded in DNA; the recognition or selection of nucleosomal substrates by remodeling complexes; and, finally, the motor action on the nucleosome exerted by the chromatin remodeler. Recent work has been able to provide crucial insights at each of these three levels that add new twists to this exciting and unfinished story, which we highlight in this perspective. Copyright © 2017 Biophysical Society. Published by Elsevier Inc. All rights reserved.
11. Reducing the risk of baby falls in maternity units.
Science.gov (United States)
Janiszewski, Helen
During a 12-month period there were 17 baby falls on the maternity wards at Nottingham University Hospitals Trust; two of the babies who fell were injured. By collecting information about the baby falls and how they happened, we were able to compile a guideline for both preventing and managing baby falls. This formed part of the trust's patient safety programme. We then piloted and implemented risk-prevention strategies for baby falls. These involved a risk assessment to identify women needing closer observation and the installation of bedside cots. These strategies brought about a marked reduction of baby falls and are now being established across all the maternity units across the trust.
12. Mothers' use of and attitudes to BabyCheck.
OpenAIRE
Thomson, Hilary; Ross, Sue; Wilson, Philip; McConnachie, Alex; Watson, Richard
2002-01-01
A copy of BabyCheck was sent to 497 mothers shortly after the birth of their baby. Six months later they were sent a questionnaire asking about their use of and attitudes to, BabyCheck. Questionnaires were returned by 323 (65%) mothers; 215 (67%) of them reported reading BabyCheck, the majority found it easy to understand (74%) and agreed with the advice (67%). Eighty-four (26%) of the mothers who returned the questionnaires reported using BabyCheck when their baby was ill; of these, 71% agre...
13. Reaction mechanism of the acidic hydrolysis of highly twisted amides: Rate acceleration caused by the twist of the amide bond.
Science.gov (United States)
Mujika, Jon I; Formoso, Elena; Mercero, Jose M; Lopez, Xabier
2006-08-03
We present an ab initio study of the acid hydrolysis of a highly twisted amide and a planar amide analogue. The aim of these studies is to investigate the effect that the twist of the amide bond has on the reaction barriers and mechanism of acid hydrolysis. Concerted and stepwise mechanisms were investigated using density functional theory and polarizable continuum model calculations. Remarkable differences were observed between the mechanism of twisted and planar amide, due mainly to the preference for N-protonation of the former and O-protonation of the latter. In addition, we were also able to determine that the hydrolytic mechanism of the twisted amide will be pH dependent. Thus, there is a preference for a stepwise mechanism with formation of an intermediate in the acid hydrolysis, whereas the neutral hydrolysis undergoes a concerted-type mechanism. There is a nice agreement between the characterized intermediate and available X-ray data and a good agreement with the kinetically estimated rate acceleration of hydrolysis with respect to analogous undistorted amide compounds. This work, along with previous ab initio calculations, describes a complex and rich chemistry for the hydrolysis of highly twisted amides as a function of pH. The theoretical data provided will allow for a better understanding of the available kinetic data of the rate acceleration of amides upon twisting and the relation of the observed rate acceleration with intrinsic differential reactivity upon loss of amide bond resonance.
14. Studies on the separation between higher-twist and minimum-twist in the photoproduction experiment WA69 at the CERN-OMEGA spectrometer
International Nuclear Information System (INIS)
Kingler, J.
1990-01-01
A Lund type Monte Carlo program (LUCIFER) is used to describe in perturbative QCD the pointlike component of the photon interacting on a hydrogen target. Kinematical and topological variables are developed to enhance higher twist events on the lowest order minimum twist background. The emphasis is laid on π ± , K ± higher twist mesons. (orig.)
15. VTR module: weaning foods for baby.
Science.gov (United States)
1993-01-01
Weaning should start when the baby turns 4 months old. At this stage (4 to 6 months), milk is no longer enough. Parents should introduce new foods which can meet the fast-increasing nutrition needs of the child. Among the latest materials produced by the Video Radio Production Division of the Nutrition Center of the Philippines is a VTR training module entitled "Karagdagang Pagkain ni Baby" (Weaning Foods for Baby), designed to strengthen this important aspect of child care. Specifically, the module seeks to encourage parents to introduce foods in addition to breastmilk to their 4 to 6 month old children and to start giving them "complete" meals from 6 months onward. It provides suggestions on the kinds of foods or food combinations to give to the baby and encourages home food production (backyard gardening, poultry-raising etc) to supply food requirements of growing children. Contents of the module include how-to's on weaning food preparation (mashing, straining, flaking, chopping, scraping, etc), prescriptions on the kinds and amounts of foods for babies; and food combinations (porridge or rice and a viand from the 3 basic food groups: energy-giving, body building and regulating). For instance, at 4 months old, the baby may be given lugao (porridge), soup and fruits; at 5 months, eggs, vegetables and beans; at 6 months, fish/meat, oil or gata (coconut oil). With a running time of 18 minutes, the module uses computer graphics to highlight food items, recommended amounts, and age group requirements in the text, and applies digital multi-effects to ensure smooth traditions. full text
16. Phosphorylation of basic helix-loop-helix transcription factor Twist in development and disease.
Science.gov (United States)
Xue, Gongda; Hemmings, Brian A
2012-02-01
The transcription factor Twist plays vital roles during embryonic development through regulating/controlling cell migration. However, postnatally, in normal physiological settings, Twist is either not expressed or inactivated. Increasing evidence shows a strong correlation between Twist reactivation and both cancer progression and malignancy, where the transcriptional activities of Twist support cancer cells to disseminate from primary tumours and subsequently establish a secondary tumour growth in distant organs. However, it is largely unclear how this signalling programme is reactivated or what signalling pathways regulate its activity. The present review discusses recent advances in Twist regulation and activity, with a focus on phosphorylation-dependent Twist activity, potential upstream kinases and the contribution of these factors in transducing biological signals from upstream signalling complexes. The recent advances in these areas have shed new light on how phosphorylation-dependent regulation of the Twist proteins promotes or suppresses Twist activity, leading to differential regulation of Twist transcriptional targets and thereby influencing cell fate.
17. Cerebral Palsy Checklist: Babies & Preschoolers (Birth to age 5)
Science.gov (United States)
... Staying Safe Videos for Educators Search English Español Cerebral Palsy Checklist: Babies & Preschoolers KidsHealth / For Parents / Cerebral Palsy Checklist: Babies & Preschoolers What's in this article? Step ...
18. N=1 supersymmetric extension of the baby Skyrme model
International Nuclear Information System (INIS)
Adam, C.; Queiruga, J. M.; Sanchez-Guillen, J.; Wereszczynski, A.
2011-01-01
We construct a method to supersymmetrize higher kinetic terms and apply it to the baby Skyrme model. We find that there exist N=1 supersymmetric extensions for baby Skyrme models with arbitrary potential.
19. When Your Baby's in the NICU (Neonatal Intensive Care Unit)
Science.gov (United States)
... baby's progress? Is wi-fi access available for smartphones and other devices? Can we use our cellphones ... you also want to allow periods of undisturbed sleep. Let your baby set the pace for your ...
20. Baby Teeth Link Autism and Heavy Metals, NIH Study Suggests
Science.gov (United States)
... Release Thursday, June 1, 2017 Baby teeth link autism and heavy metals, NIH study suggests Cross-section ... Sinai Health System Baby teeth from children with autism contain more toxic lead and less of the ...
1. Baby Cry Detection in Domestic Environment using Deep Learning
OpenAIRE
Ijzerman, Hans
2017-01-01
Automatic detection of a baby cry in audio signals is an essential step in applications such as remote baby monitoring. It is also important for researchers, who study the relation between baby cry patterns and various health or developmental parameters. In this paper, we propose two machine-learning algorithms for automatic detection of baby cry in audio recordings. The first algorithm is a low-complexity logistic regression classifier, used as a reference. To train this classifier, we extra...
2. Extension-twist coupling of composite circular tubes with application to tilt rotor blade design
Science.gov (United States)
Nixon, Mark W.
1987-01-01
This investigation was conducted to determine if twist deformation required for the design of full-scale extension-twist-coupled tilt-rotor blades can be achieved within material design limit loads, and to demonstrate the accuracy of a coupled-beam analysis in predicting twist deformations. Two extension-twist-coupled tilt-rotor blade designs were developed based on theoretically optimum aerodynamic twist distributions. The designs indicated a twist rate requirement of between .216 and .333 deg/in. Agreement between axial tests and analytical predictions was within 10 percent at design limit loads. Agreement between the torsion tests and predictions was within 11 percent.
3. Finite element and analytical models for twisted and coiled actuator
Science.gov (United States)
Tang, Xintian; Liu, Yingxiang; Li, Kai; Chen, Weishan; Zhao, Jianguo
2018-01-01
Twisted and coiled actuator (TCA) is a class of recently discovered artificial muscle, which is usually made by twisting and coiling polymer fibers into spring-like structures. It has been widely studied since discovery due to its impressive output characteristics and bright prospects. However, its mathematical models describing the actuation in response to the temperature are still not fully developed. It is known that the large tensile stroke is resulted from the untwisting of the twisted fiber when heated. Thus, the recovered torque during untwisting is a key parameter in the mathematical model. This paper presents a simplified model for the recovered torque of TCA. Finite element method is used for evaluating the thermal stress of the twisted fiber. Based on the results of the finite element analyses, the constitutive equations of twisted fibers are simplified to develop an analytic model of the recovered torque. Finally, the model of the recovered torque is used to predict the deformation of TCA under varying temperatures and validated against experimental results. This work will enhance our understanding of the deformation mechanism of TCAs, which will pave the way for the closed-loop position control.
4. AKT-ions with a TWIST between EMT and MET.
Science.gov (United States)
Tang, Huifang; Massi, Daniela; Hemmings, Brian A; Mandalà, Mario; Hu, Zhengqiang; Wicki, Andreas; Xue, Gongda
2016-09-20
The transcription factor Twist is an important regulator of cranial suture during embryogenesis. Closure of the neural tube is achieved via Twist-triggered cellular transition from an epithelial to mesenchymal phenotype, a process known as epithelial-mesenchymal transition (EMT), characterized by a remarkable increase in cell motility. In the absence of Twist activity, EMT and associated phenotypic changes in cell morphology and motility can also be induced, albeit moderately, by other transcription factor families, including Snail and Zeb. Aberrant EMT triggered by Twist in human mammary tumour cells was first reported to drive metastasis to the lung in a metastatic breast cancer model. Subsequent analysis of many types of carcinoma demonstrated overexpression of these unique EMT transcription factors, which statistically correlated with worse outcome, indicating their potential as biomarkers in the clinic. However, the mechanisms underlying their activation remain unclear. Interestingly, increasing evidence indicates they are selectively activated by distinct intracellular kinases, thereby acting as downstream effectors facilitating transduction of cytoplasmic signals into nucleus and reprogramming EMT and mesenchymal-epithelial transition (MET) transcription to control cell plasticity. Understanding these relationships and emerging data indicating differential phosphorylation of Twist leads to complex and even paradoxical functionalities, will be vital to unlocking their potential in clinical settings.
5. The Twist Tensor Nuclear Norm for Video Completion.
Science.gov (United States)
Hu, Wenrui; Tao, Dacheng; Zhang, Wensheng; Xie, Yuan; Yang, Yehui
2017-12-01
In this paper, we propose a new low-rank tensor model based on the circulant algebra, namely, twist tensor nuclear norm (t-TNN). The twist tensor denotes a three-way tensor representation to laterally store 2-D data slices in order. On one hand, t-TNN convexly relaxes the tensor multirank of the twist tensor in the Fourier domain, which allows an efficient computation using fast Fourier transform. On the other, t-TNN is equal to the nuclear norm of block circulant matricization of the twist tensor in the original domain, which extends the traditional matrix nuclear norm in a block circulant way. We test the t-TNN model on a video completion application that aims to fill missing values and the experiment results validate its effectiveness, especially when dealing with video recorded by a nonstationary panning camera. The block circulant matricization of the twist tensor can be transformed into a circulant block representation with nuclear norm invariance. This representation, after transformation, exploits the horizontal translation relationship between the frames in a video, and endows the t-TNN model with a more powerful ability to reconstruct panning videos than the existing state-of-the-art low-rank models.
6. Healthy Family 2009: Bringing in Baby
Science.gov (United States)
... anemia, prevalent among African Americans. 8 Great Information Sources About Baby and You 1. medlineplus.gov —"Teenage Pregnancy" and a vast array of other accessible information on pregnancy from the National Library of Medicine. 2. www.kidshealth.org —"Exercising During ...
7. The Incredible Years Parents and Babies Program:
DEFF Research Database (Denmark)
Pontoppidan, Maiken W.; Klest, Sihu; Sandoy, Tróndur Møller
2016-01-01
Introduction Infancy is an important period of life; adverse experiences during this stage can have both immediate and lifelong impacts on the child’s mental health and well-being. This study evaluates the effects of the Incredible Years Parents and Babies (IYPB) program as a universal intervention...
8. Feeding Tips For Your Baby with CHD
Science.gov (United States)
... weight as rapidly as other infants, despite your hard work and persistence, and at times this may be ... the bottle thickens the formula and makes it hard for your baby to suck it out ... and snacks can play a very important role in providing good nutrition. ...
9. Giant lower oesophageal ulcer Bushman baby
African Journals Online (AJOL)
1983-02-26
Feb 26, 1983 ... The case of a giant, penetrating lower oesophageal ulcer in a 14-month-old Bushman baby is reported. This would probably be classified as a Barrett's ulcer. Histological examination showed that the ulcer developed in columnar epithelium and that there was normal stratified squamous oesophageal.
10. The baby has not come: obstructed labour
African Journals Online (AJOL)
Introduction. This article is about how to recognize obstructed labour and deal with it in a way that preserves the life and health of mother and child. It is for midwives and others who work in maternity care and is based on our experiences in Yei, South Sudan. Obstructed labour means that the baby is too big to pass through ...
11. Mermaid baby | Khan | SA Journal of Radiology
African Journals Online (AJOL)
We were recently intrigued by a baby born at Kalafong Hospital with fused lower extremities resembling a mermaid, which caused us to search for the background and origin of this entity called sirenomelia. Full Text: EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT · DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT.
12. Welcoming a New Baby into Your Family
Science.gov (United States)
... it's also OK if you miss the way things were before the baby came. If you feel left out or need some attention, tell your mom or dad. Also be sure to tell a parent if you're having trouble getting your homework done or you're not getting enough sleep. Before ...
13. Expedient Treatment of a Collodion Baby
Directory of Open Access Journals (Sweden)
Michael Chung
2011-01-01
Full Text Available Only ~270 cases of collodion babies have been reported in the literature since 1892. As the name suggests, the term “collodion baby” refers to a phenotype that can be characterized by a yellow, shiny, tight parchment-like membrane stretched over the skin. Although the collodion membrane is only an evanescent condition of the newborn, neonatal complications can occur in 45% of all collodion babies, leading to a mortality rate of ~11% in the first few weeks of life. Most children born as collodion babies will spontaneously desquamate within 2 weeks, but may be as long as 3 months. Eventually, these children develop signs of one of several types of ichthyosis, which gives the skin the appearance of “fish scales.” We report a unique case of a Caucasian male that was born as a Collodion baby at the University of Kentucky Children's Hospital in Lexington, Kentucky. Although the impairment of the skin barrier function put the patient at risk for a number of complications, he improved significantly after being treated with emollients and antibiotics. In contrast to previous findings, we found that skin emollients were beneficial and did not increase the risk of infection.
14. Babies Bottom Out--A 'Maybe Boom'
Science.gov (United States)
Science News, 1977
1977-01-01
Data for the period September 1976 through April 1977 indicate a rise in the United States birth rate; however, the rate is still below the replacement level. It is speculated that the increase is an "echo" effect to the post-World War II baby boom which peaked in 1957. (SL)
15. Faith, existence and birth of preterm babies
DEFF Research Database (Denmark)
Rasmussen, Christina Prinds
The aim is to explore if becoming a mother preterm of a premature baby, actualises existential and religious issues, and to explore the impact of the considerations in their way of coping. It is thus to shed light on these issues, that can both function as a positive coping-resource and the oppos...
16. Me? Have a Baby? Preconception Health
Centers for Disease Control (CDC) Podcasts
2012-10-01
Preconception health means taking care of your own health now so youâll be healthy for yourself and your future baby. Created: 10/1/2012 by National Center on Birth Defects and Developmental Disabilities (NCBDDD). Date Released: 10/1/2012.
17. Me? Have Another Baby? Preconception Health
Centers for Disease Control (CDC) Podcasts
2012-10-01
Preconception health means taking care of your own health now so youâll be healthy for yourself and your future baby. Created: 10/1/2012 by National Center on Birth Defects and Developmental Disabilities (NCBDDD). Date Released: 10/1/2012.
18. Breech Babies: What Can I Do If My Baby Is Breech?
Science.gov (United States)
... Control Sex and Sexuality Birth Control Family Health Infants and Toddlers Kids and Teens Pregnancy and Childbirth ... Pregnancy: First TrimesterTaking Care of You and Your Baby While You’re PregnantChanges in Your Body During ...
19. Kangaroo Mother Care Management of a 750 Ggrammes Baby: A ...
African Journals Online (AJOL)
This paper presents the successful management of 750 grammes low birth weight baby using kangaroo mother care in the hospital and at home. The baby had suffered a variety of morbidities associated with prematurity in the early neonatal period. Key words: Kangaroo mother care, low birth weight babies ...
20. Implementing the Fussy Baby Network[R] Approach
Science.gov (United States)
Gilkerson, Linda; Hofherr, Jennifer; Heffron, Mary Claire; Sims, Jennifer Murphy; Jalowiec, Barbara; Bromberg, Stacey R.; Paul, Jennifer J.
2012-01-01
Erikson Institute Fussy Baby Network[R] (FBN) developed an approach to engaging parents around their urgent concerns about their baby's crying, sleeping, or feeding in a way which builds their longer-term capacities as parents. This approach, called the FAN, is now in place in new Fussy Baby Network programs around the country and is being infused…
1. Crying Baby: What to Do When Your Newborn Cries
Science.gov (United States)
... a crying baby — and renewing your ability to handle the tears. By Mayo Clinic Staff The dream: Your baby sleeps through the night after just a few weeks, gurgles happily while you run errands and fusses only when hunger strikes. The reality: Your baby's favorite playtime is after ...
2. Birthing Healthy Babies (A Cup of Health with CDC)
Centers for Disease Control (CDC) Podcasts
Every four and a half minutes a baby is born with a birth defect in the United States. That means nearly 120,000 babies, or about three percent of all babies born each year. In this podcast, Dr. Suzanne Gilboa discusses ways to prevent birth defects.
3. Infants & Toddlers: How Babies Use Gestures to Communicate
Science.gov (United States)
Honig, Alice Sterling
2004-01-01
Evolution has provided babies with wonderful ways to get the loving attention and care that they need from adults. When a baby is distressed, his cry is the most primitive and powerful tool for bringing help. By the time a baby is 2 or 3 months old, his dazzling smile and crooked grin evokes tenderness, smiles, and nurturance from adults who are…
4. Beliefs about the use of baby walkers.
Science.gov (United States)
Chagas, Paula S C; Mancini, Marisa C; Tirado, Marcella G A; Megale, Luiz; Sampaio, Rosana F
2011-01-01
To understand the opinion of the parents about the baby walker and compare the age of gait acquisition between infants that used a walker and those that did not. In this quali-quantitative study, an interview involving a semi-structured questionnaire was carried out with 26 parents, 14 of whose infants used the equipment (BWG) and 12 of whose infants did not (NBWG) prior to gait acquisition. After extensive content analysis, categories for interpreting the results emerged. For data triangulation, the age of gait acquisition was documented by weekly telephone contact. Student's t-test was used for comparison between groups with a significance level of α=0.05. The following categories were identified in the parents' reports: a) information about the baby walker; b) doubt/decision to use it vs. certainty about not using it; c) beliefs about the use of a baby-walker; and d) benefits and harm from use. The age of independent gait acquisition did not differ between groups (p=0.837): BWG initiated gait at 376.17 (SD=32.62) days and NBWG did so at 378.75 (SD=27.99) days. The beliefs and feelings that permeate the decision to use a baby walker illustrate the different rationales adopted by parents about the role of this equipment in the child's development of gait and autonomy. The use of a baby walker did not influence the age of gait acquisition. The results broaden the understanding of choices that influence child-rearing practices prior to gait acquisition.
5. Optical patterning and dynamics of torons and hopfions in a chiral nematic with photo-tunable equilibrium pitch
Science.gov (United States)
Sohn, Hayley; Ackerman, Paul; Smalyukh, Ivan
Three-dimensional (3D) topological solitons arise in field theories ranging from particle physics to condensed matter and cosmology. They are the 3D counterparts of 2D skyrmions (often called `baby skyrmions''), which attract a great deal of interest in studies of chiral ferromagnets and enable the emerging field of skyrmionics. In chiral nematic liquid crystals, the stability of such solitons is enhanced by the chiral medium's tendency to twist the director field describing the 3D spatial patterns of molecular alignment. However, their experimental realization, control and detailed studies remain limited. We combine experimental realization and numerical modeling of such light-responsive solitonic structures, including elementary torons and hopfions, in confined chiral nematic liquid crystals with photo-tunable cholesteric pitch. We show that the optical tunability of the pitch allows for using low-intensity light to control the soliton stability, dimensions, spatial patterning and dynamics.
6. Fast Torsional Artificial Muscles from NiTi Twisted Yarns.
Science.gov (United States)
Mirvakili, Seyed M; Hunter, Ian W
2017-05-17
Torsional artificial muscles made of multiwalled carbon nanotube/niobium nanowire yarns have shown remarkable torsional speed and gravimetric torque. The muscle structure consists of a twisted yarn with half of its length infiltrated with a stimuli-responsive guest material such as paraffin wax. The volumetric expansion of the guest material creates the torsional actuation in the yarn. In the present work, we show that this type of actuation is not unique to wax-infiltrated carbon multiwalled nanotube (MWCNT) or niobium nanowire yarns and that twisted yarn of NiTi alloy fibers also produces fast torsional actuation. By gold-plating half the length of a NiTi twisted yarn and Joule heating it, we achieved a fully reversible torsional actuation of up to 16°/mm with peak torsional speed of 10 500 rpm and gravimetric torque of 8 N·m/kg. These results favorably compare to those of MWCNTs and niobium nanowire yarns.
7. From starproducts to Drinfeld-twists. Present and future applications
International Nuclear Information System (INIS)
Koch, Florian
2008-01-01
Physics comes up with models that invoke noncommutative structures in configuration space. Such structures are dual to the deformed coalgebra sector of a represented symmetry algebra. In the mean time such deformations are performed in terms of the symmetry algebra itself via twists or quasitriangular structures. One might thus find oneself in the bad situation that the symmetry algebra is not large enough to provide the required twist that dually matches the noncommutative structure found. It thus has to remain in the unpleasant state of being without any notion of symmetry. We show how starproducts can be pushed to twists by introducing a larger algebra that accommodates any finite dimensional representation of a Lie-algebra. This new algebra is similar to a Heisenberg-algebra but in contrast to the latter can be enhanced to a Hopf-algebra. Some Examples are given. (author)
8. Twisted vertex algebras, bicharacter construction and boson-fermion correspondences
International Nuclear Information System (INIS)
Anguelova, Iana I.
2013-01-01
The boson-fermion correspondences are an important phenomena on the intersection of several areas in mathematical physics: representation theory, vertex algebras and conformal field theory, integrable systems, number theory, cohomology. Two such correspondences are well known: the types A and B (and their super extensions). As a main result of this paper we present a new boson-fermion correspondence of type D-A. Further, we define a new concept of twisted vertex algebra of order N, which generalizes super vertex algebra. We develop the bicharacter construction which we use for constructing classes of examples of twisted vertex algebras, as well as for deriving formulas for the operator product expansions, analytic continuations, and normal ordered products. By using the underlying Hopf algebra structure we prove general bicharacter formulas for the vacuum expectation values for two important groups of examples. We show that the correspondences of types B, C, and D-A are isomorphisms of twisted vertex algebras
9. Iterative methods for overlap and twisted mass fermions
International Nuclear Information System (INIS)
Chiarappa, T.; Jansen, K.; Shindler, A.; Wetzorke, I.; Scorzato, L.; Urbach, C.; Wenger, U.
2006-09-01
We present a comparison of a number of iterative solvers of linear systems of equations for obtaining the fermion propagator in lattice QCD. In particular, we consider chirally invariant overlap and chirally improved Wilson (maximally) twisted mass fermions. The comparison of both formulations of lattice QCD is performed at four fixed values of the pion mass between 230 MeV and 720 MeV. For overlap fermions we address adaptive precision and low mode preconditioning while for twisted mass fermions we discuss even/odd preconditioning. Taking the best available algorithms in each case we find that calculations with the overlap operator are by a factor of 30-120 more expensive than with the twisted mass operator. (orig.)
10. Iterative methods for overlap and twisted mass fermions
Energy Technology Data Exchange (ETDEWEB)
Chiarappa, T. [Univ. di Milano Bicocca (Italy); Jansen, K.; Shindler, A.; Wetzorke, I. [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany). John von Neumann-Inst. fuer Computing NIC; Nagai, K.I. [Wuppertal Univ. (Gesamthochschule) (Germany). Fachbereich Physik; Papinutto, M. [INFN Sezione di Roma Tre, Rome (Italy); Scorzato, L. [European Centre for Theoretical Studies in Nuclear Physics and Related Areas (ECT), Villazzano (Italy); Urbach, C. [Liverpool Univ. (United Kingdom). Dept. of Mathematical Sciences; Wenger, U. [ETH Zuerich (Switzerland). Inst. fuer Theoretische Physik
2006-09-15
We present a comparison of a number of iterative solvers of linear systems of equations for obtaining the fermion propagator in lattice QCD. In particular, we consider chirally invariant overlap and chirally improved Wilson (maximally) twisted mass fermions. The comparison of both formulations of lattice QCD is performed at four fixed values of the pion mass between 230 MeV and 720 MeV. For overlap fermions we address adaptive precision and low mode preconditioning while for twisted mass fermions we discuss even/odd preconditioning. Taking the best available algorithms in each case we find that calculations with the overlap operator are by a factor of 30-120 more expensive than with the twisted mass operator. (orig.)
11. Template preparation of twisted nanoparticles of mesoporous silica
Institute of Scientific and Technical Information of China (English)
Kui Niu; Zhongbin Ni; Chengwu Fu; Tatsuo Kaneko; Mingqing Chen
2011-01-01
Optical isomers of N-lauroyl-L-(or-D-) alanine sodium salt {C12-L-(or-D-)AlaS} surfactants were used for the preparation of mesoporous silica nanoparticles with a twisted hexagonal rod-like morphology. Thermogravimetric analysis (TGA) was used to determine the temperature for template removal. Circular dichroism (CD) spectra of the surfactant solution with various compositions illustrated the formation and supramolecular assembly of protein-like molecular architecture leading to formation of twisted nanoparticles. Scanning electron microscopy (SEM),high-resolution transmission electron microscopy (HRTEM)and X-ray powder diffraction (XRD) patterns of these as-synthesized mesoporous silica confirmed that the twisted morphology of these nanoparticles was closely related to the supramolecular-assembled complex of amino acid surfactants.
12. Twisted spin Sutherland models from quantum Hamiltonian reduction
International Nuclear Information System (INIS)
Feher, L; Pusztai, B G
2008-01-01
Recent general results on Hamiltonian reductions under polar group actions are applied to study some reductions of the free particle governed by the Laplace-Beltrami operator of a compact, connected, simple Lie group. The reduced systems associated with arbitrary finite-dimensional irreducible representations of the group by using the symmetry induced by twisted conjugations are described in detail. These systems generically yield integrable Sutherland-type many-body models with spin, which are called twisted spin Sutherland models if the underlying twisted conjugations are built on non-trivial Dynkin diagram automorphisms. The spectra of these models can be calculated, in principle, by solving certain Clebsch-Gordan problems, and the result is presented for the models associated with the symmetric tensorial powers of the defining representation of SU(N)
13. Reversible Twisting of Primary Amides via Ground State N-C(O) Destabilization: Highly Twisted Rotationally Inverted Acyclic Amides.
Science.gov (United States)
Meng, Guangrong; Shi, Shicheng; Lalancette, Roger; Szostak, Roman; Szostak, Michal
2018-01-17
Since the seminal studies by Pauling in 1930s, planarity has become the defining characteristic of the amide bond. Planarity of amides has central implications for the reactivity and chemical properties of amides of relevance to a range of chemical disciplines. While the vast majority of amides are planar, nonplanarity has a profound effect on the properties of the amide bond, with the most common method to restrict the amide bond relying on the incorporation of the amide function into a rigid cyclic ring system. In a major departure from this concept, here, we report the first class of acyclic twisted amides that can be prepared, reversibly, from common primary amides in a single, operationally trivial step. Di-tert-butoxycarbonylation of the amide nitrogen atom yields twisted amides in which the amide bond exhibits nearly perpendicular twist. Full structural characterization of a range of electronically diverse compounds from this new class of twisted amides is reported. Through reactivity studies we demonstrate unusual properties of the amide bond, wherein selective cleavage of the amide bond can be achieved by a judicious choice of the reaction conditions. Through computational studies we evaluate structural and energetic details pertaining to the amide bond deformation. The ability to selectively twist common primary amides, in a reversible manner, has important implications for the design and application of the amide bond nonplanarity in structural chemistry, biochemistry and organic synthesis.
14. Borel resummation of soft gluon radiation and higher twists
International Nuclear Information System (INIS)
Forte, Stefano; Ridolfi, Giovanni; Rojo, Joan; Ubiali, Maria
2006-01-01
We show that the well-known divergence of the perturbative expansion of resummed results for processes such as deep-inelastic scattering and Drell-Yan in the soft limit can be treated by Borel resummation. The divergence in the Borel inversion can be removed by the inclusion of suitable higher twist terms. This provides us with an alternative to the standard 'minimal prescription' for the asymptotic summation of the perturbative expansion, and it gives us some handle on the role of higher twist corrections in the soft resummation region
15. Modeling higher twist contributions to deep inelastic scattering with diquarks
International Nuclear Information System (INIS)
Anselmino, M.
1994-01-01
The most recent detailed data on the unpolarized nucleon structure functions allow a precise determination of higher twist contributions. Quark-quark correlations induced by color forces are expected to be a natural explanation for such effects; indeed, a quark-diquark picture of the nucleon, previously introduced in the description of several exclusive processes at intermediate Q 2 values, is found to model the proton higher twist data with great accuracy. The resulting parameters are consistent with the diquark properties suggested by other experimental and theoretical analyses. (author)
16. Modelling higher twist contributions to deep inelastic scattering with diquarks
International Nuclear Information System (INIS)
Anselmino, M.; Caruso, F.; Penna Firme, A.; Soares, J.; Mello Neto, J.R.T. de
1994-08-01
The most recent detailed data on the unpolarized nucleon structure functions allow a precise determination of higher twist contributions. Quark-quark correlations induced by colour forces are expected to be a natural explanation for such effects: indeed, a quark-diquark picture of the nucleon, previously introduced in the description of several exclusive processes at intermediate Q 2 values, is found to model the proton higher twist data with great accuracy. The resulting parameters are consistent with the diquark properties suggested by other experimental and theoretical analyses. (author). 15 refs, 5 figs
17. Anomalous phase shift in a twisted quantum loop
International Nuclear Information System (INIS)
Taira, Hisao; Shima, Hiroyuki
2010-01-01
The coherent motion of electrons in a twisted quantum ring is considered to explore the effect of torsion inherent to the ring. Internal torsion of the ring composed of helical atomic configuration yields a non-trivial quantum phase shift in the electrons' eigenstates. This torsion-induced phase shift causes novel kinds of persistent current flow and an Aharonov-Bohm-like conductance oscillation. The two phenomena can occur even when no magnetic flux penetrates inside the twisted ring, thus being in complete contrast with the counterparts observed in untwisted rings.
18. Note on twisted elliptic genus of K3 surface
Energy Technology Data Exchange (ETDEWEB)
Eguchi, Tohru, E-mail: eguchi@yukawa.kyoto-u.ac.j [Yukawa Institute for Theoretical Physics, Kyoto University, Kyoto 606-8502 (Japan); Hikami, Kazuhiro, E-mail: KHikami@gmail.co [Department of Mathematics, Naruto University of Education, Tokushima 772-8502 (Japan)
2011-01-03
We discuss the possibility of Mathieu group M{sub 24} acting as symmetry group on the K3 elliptic genus as proposed recently by Ooguri, Tachikawa and one of the present authors. One way of testing this proposal is to derive the twisted elliptic genera for all conjugacy classes of M{sub 24} so that we can determine the unique decomposition of expansion coefficients of K3 elliptic genus into irreducible representations of M{sub 24}. In this Letter we obtain all the hitherto unknown twisted elliptic genera and find a strong evidence of Mathieu moonshine.
19. Note on twisted elliptic genus of K3 surface
International Nuclear Information System (INIS)
Eguchi, Tohru; Hikami, Kazuhiro
2011-01-01
We discuss the possibility of Mathieu group M 24 acting as symmetry group on the K3 elliptic genus as proposed recently by Ooguri, Tachikawa and one of the present authors. One way of testing this proposal is to derive the twisted elliptic genera for all conjugacy classes of M 24 so that we can determine the unique decomposition of expansion coefficients of K3 elliptic genus into irreducible representations of M 24 . In this Letter we obtain all the hitherto unknown twisted elliptic genera and find a strong evidence of Mathieu moonshine.
20. Stability of short wavelength tearing and twisting modes
International Nuclear Information System (INIS)
Waelbroeck, F.L.
1998-01-01
The stability and mutual interaction of tearing and twisting modes in a torus is governed by matrices that generalize the well-known Δ' stability index. The diagonal elements of these matrices determine the intrinsic stability of modes that reconnect the magnetic field at a single resonant surface. The off-diagonal elements indicate the strength of the coupling between the different modes. The author shows how the elements of these matrices can be evaluated, in the limit of short wavelength, from the free energy driving radially extended ballooning modes. The author applies the results by calculating the tearing and twisting Δ' for a model high-beta equilibrium with circular flux surfaces | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.6885315179824829, "perplexity": 3510.828873369412}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2018-43/segments/1539583510754.1/warc/CC-MAIN-20181016134654-20181016160154-00376.warc.gz"} |
http://en.wikipedia.org/wiki/Omnidirectional_antenna | Omnidirectional antenna
The radiation pattern of a simple omnidirectional antenna, a vertical half-wave dipole antenna. In this graph the antenna is at the center of the "donut," or torus. Radial distance from the center represents the power radiated in that direction. The power radiated is maximum in horizontal directions, dropping to zero directly above and below the antenna.
Types
Radiation pattern of a 3λ/2 monopole antenna. Although the radiation of an omnidirectional antenna is symmetrical in azmuthal directions, it may vary in a complicated way with elevation angle, having lobes and nulls at different angles.
Common types of low-gain omnidirectional antennas are the whip antenna, "Rubber Duck" or "Rubber Ducky", ground plane antenna, vertically oriented dipole antenna, discone antenna, mast radiator, horizontal loop antenna (sometimes known colloquially as a 'circular aerial' because of the shape), and the halo antenna.
Higher-gain omnidirectional antennas can also be built. "Higher gain" in this case means that the antenna radiates less energy at higher and lower elevation angles and more in the horizontal directions. High-gain omnidirectional antennas are generally realized using collinear dipole arrays. These arrays consist of half-wavelength dipoles with a phase shifting method between each element that ensures the current in each dipole is in phase.[1] The Coaxial Colinear or COCO antenna uses transposed coaxial sections to produce in-phase half-wavelength radiators. A Franklin Array uses short U-shaped half-wavelength sections whose radiation cancels in the far-field to bring each half-wavelength dipole section into equal phase.
Types of higher gain omnidirectional antennas are the coaxial collinear (COCO) antenna[2] and Omnidirectional Microstrip Antenna (OMA).[3]
Some planar antennas (constructed from printed circuit board) are omnidirectional antennas.[4]
Analysis
Vertical polarized VHF- UHF biconical antenna 170 – 1100 MHz with omni directional H-plane pattern
Omnidirectional radiation patterns are produced by the simplest practical antennas, monopole and dipole antennas, consisting of one or two straight rod conductors on a common axis. Antenna gain (G) is defined as antenna efficiency (e) multiplied by antenna directivity (D) which is expressed mathematically as: $G = eD$. A useful relationship between omnidirectional radiation pattern directivity (D) in decibels and half-power beamwidth (HPBW) based on the assumption of a $\sin{b\theta} / {b\theta}$ pattern shape is:[5]
$D = 10\log_{10} {\left ({101.5\over {HPBW - 0.00272(HPBW)^2}}\right )} \;\; dB.$
4. ^ Yanaga; Kurashima; Arita; Kobayashi (2003?). "A Planar UWB Monopole Antenna Formed on a Printed Circuit Board" (PDF). Check date values in: |date= (help) | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 3, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.7943293452262878, "perplexity": 5516.417186429936}, "config": {"markdown_headings": false, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2014-42/segments/1413507442900.2/warc/CC-MAIN-20141017005722-00278-ip-10-16-133-185.ec2.internal.warc.gz"} |
https://hal-insu.archives-ouvertes.fr/insu-03047218v1 | Comparison of stratospheric ozone profiles and their seasonal variations as measured by lidar and Stratospheric Aerosol and Gas Experiment during 1988 - Archive ouverte HAL Access content directly
Journal Articles Journal of Geophysical Research: Atmospheres Year : 1990
Comparison of stratospheric ozone profiles and their seasonal variations as measured by lidar and Stratospheric Aerosol and Gas Experiment during 1988
I. Stuart Mcdermid
• Function : Author
Sophie Godin
Pi-Huan Wang
• Function : Author
M. Patrick Mccomick
• Function : Author
Abstract
A ground-based, high power, laser remote sensing system for measurements of stratospheric ozone concentration profiles has been in operation at the Jet Propulsion Laboratory Table Mountain Facility located in southern California, +34.4°N, -117.7°W, since January 1988. The seasonal variations observed in the ozone profiles, during 1988 and as a function of altitude, are described here. These profiles are compared with those from the Stratospheric Aerosol and Gas Experiment (SAGE II) satellite instrument made within a radius of 1000 km from the lidar and also with the zonal mean measurements made in the band 34.4°±5°. Comparison with the proposed new CIRA ozone reference model has also been carried out. The seasonal variations, between 25 km and 50 km, observed by the two instruments and indicated by the reference model are in good agreement.
Dates and versions
insu-03047218 , version 1 (02-02-2021)
Identifiers
• HAL Id : insu-03047218 , version 1
• DOI :
Cite
I. Stuart Mcdermid, Sophie Godin, Pi-Huan Wang, M. Patrick Mccomick. Comparison of stratospheric ozone profiles and their seasonal variations as measured by lidar and Stratospheric Aerosol and Gas Experiment during 1988. Journal of Geophysical Research: Atmospheres, 1990, 95 (D5), pp.5605-5612. ⟨10.1029/JD095iD05p05605⟩. ⟨insu-03047218⟩
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La Formule des Traces Tordue d'après le Friday Morning Seminar
Jean-Pierre Labesse, Institut Mathématique de Luminy, Marseille, France, and Jean-Loup Waldspurger, Institut Mathématique de Jussieu, Paris, France
with a Foreword by Robert Langlands
A co-publication of the AMS and Centre de Recherches Mathématiques.
Note to readers: This book is in French.
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CRM Monograph Series
2013; 234 pp; hardcover
Volume: 31
ISBN-10: 0-8218-9441-2
ISBN-13: 978-0-8218-9441-5
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The trace formula for an arbitrary connected reductive group over a number field was developed by James Arthur. The twisted case was the subject of the Friday Morning Seminar at the Institute for Advanced Study in Princeton during the 1983-1984 academic year. During this seminar, lectures were given by Laurent Clozel, Jean-Pierre Labesse and Robert Langlands. Having been written quite hastily, the lecture notes of this seminar were in need of being revisited. The authors' ambition is to give, following these notes, a complete proof of the twisted trace formula in its primitive version, i.e., its noninvariant form. This is a part of the project of the Parisian team led by Laurent Clozel and Jean-Loup Waldspurger. Their aim is to give a complete proof of the stable form of the twisted trace formula, and to provide the background for the forthcoming book by James Arthur on twisted endoscopy for the general linear group with application to symplectic and orthogonal groups.
Titles in this series are co-published with the Centre de Recherches Mathématiques. | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.2289760708808899, "perplexity": 2829.6696990724763}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2015-48/segments/1448398447729.93/warc/CC-MAIN-20151124205407-00259-ip-10-71-132-137.ec2.internal.warc.gz"} |
https://math.stackexchange.com/questions/1404137/using-lamberts-w-function-to-solve-this-equation/1404156 | # Using Lambert's W Function to solve this equation
I'm attempting to solve the following equation (eventually with Lambert's W Function having checked the solution on Wolfram Alpha):
$$100n^2 = 2^n$$
I got as far as follows but I am unsure how to progress:
$$\ln100 + 2\ln(n) = n\ln2$$
Any suggestions would be much appreciated.
To use Lambert W you may proceed this way : \begin{align} 100\,n^2 &= 2^n\\ (10\,n)^2 &= e^{n\log 2}\\ 10\,n &= \pm e^{n\log 2/2}\\ \left(-\,n \log 2/2\right) e^{-n\log 2/2}&= \mp (\log 2)/{20}\\ -\,n \log 2/2&=W\left(\mp (\log 2)/20\right)\\ \end{align} The negative argument (see wikipedia) will be between $-\dfrac 1e$ and $0$ and return you two solutions :
1. $-\frac{2}{\log 2}W_{-1}\left(-\frac{\log 2}{20}\right)\approx 14.324727837\quad$ and
2. $-\frac{2}{\log 2}W\left(-\frac{\log 2}{20}\right)\approx 0.1036578164$
while the positive argument will return simply
3. $-\frac{2}{\log 2}W\left(\frac{\log 2}{20}\right)\approx -0.0967040343267$
$$2^n=100n^2$$
$$2^n n^{-2}=100$$
Raising to the power of $-1/2$:
$$2^{-n/2} n= \pm\frac{1}{10}$$
$$e^{- 1/2 \log (2) \cdot n } n= \pm\frac{1}{10}$$
$$e^{- 1/2 \log (2) \cdot n } (- 1/2 \log (2) n)=\pm\frac{1/2 \log (2) }{10}$$
$$e^{- 1/2 \log (2) \cdot n } (- 1/2 \log (2) n)=\pm\frac{\log (2) }{20}$$
$$n = \frac{W\left(\pm\frac{\log (2) }{20}\right)}{-1/2 \log(2)}$$
$$n = -\frac{2W\left(\pm\frac{\log (2) }{20}\right)}{\log(2)}$$
Now we must consider the $\pm$ sign and the different branches of W to obtain the answers in Dr. Sonnhard Graubner's answer.
We obtain $$n_1=-2\,{\frac {{\rm W} \left(-1/20\,\ln \left( 2 \right) \right)}{\ln \left( 2 \right) }}$$ $$n_2=-2\,{\frac {{\rm W} \left(-1,-1/20\,\ln \left( 2 \right) \right)}{ \ln \left( 2 \right) }}$$ $$n_3=-2\,{\frac {{\rm W} \left(1/20\,\ln \left( 2 \right) \right)}{\ln \left( 2 \right) }}$$
• Apologies, there was indeed a typo in the original problem. Would you be able to provide some additional working prior to these final solutions to aid understanding? Thank you. – Joshua Aug 20 '15 at 17:43 | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 1, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 1, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9990691542625427, "perplexity": 1499.3327528806558}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 20, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2019-43/segments/1570987835748.66/warc/CC-MAIN-20191023173708-20191023201208-00546.warc.gz"} |
https://www.shaalaa.com/concept-notes/concentration-of-a-solution_6272 | # Concentration of a Solution
#### definition
• Unsaturated solution: If the amount of solute contained in a solution is less than the saturation level, it is called an unsaturated solution. (till it is dissolving).
• Saturated solution: When no more solute can be dissolved in a solution at a given temperature, it is called a saturated solution.
• Solubility: The amount of the solute present in the saturated solution at this temperature is called its solubility.
# Concentration of a Solution:
• Take salt and dissolve it in water.
• After a time, it won’t be soluble.
• Heat it and try dissolving.
• It will dissolve!
• Try adding more and dissolve it.
From the about activity, the following can be inferred!
1. Unsaturated solution: If the amount of solute contained in a solution is less than the saturation level, it is called an unsaturated solution. (till it is dissolving).
2. Saturated solution: When no more solute can be dissolved in a solution at a given temperature, it is called a saturated solution.
3. Solubility: The amount of the solute present in the saturated solution at this temperature is called its solubility.
## How will you decide how concentrated the solution is?
Concentration of solution = " Amount of solute"/"Amount of solution" "or" "Amount of solute"/"Amount of solvent"
There are various ways of expressing the concentration of a solution
1. "Mass by mass percentage of a solution" = "Mass of solute"/"Mass of solution" xx 100
2. "Mass by volume percentage of a solution" = "Mass of solute"/"Volume of solution" xx 100.
#### Example
A solution contains 40 g of common salt in 320 g of water. Calculate the concentration in terms of mass by the mass percentage of the solution.
Mass of solute (salt) = 40 g
Mass of solvent (water) = 320 g
We know,
Mass of solution = Mass of solute + Mass of solvent
= 40 g + 320 g
= 360 g
Mass percentage of solution = "Mass of solute"/"Mass of solution" xx 100
= 40/360 xx 100
= 11.1%
#### Example
To make a saturated solution, 36 g of sodium chloride is dissolved in 100 g of water at 293 K. Find its concentration at this temperature.
Mass of solute (sodium chloride) = 36 g (Given)
Mass of solvent (water) = 100 g (Given)
Then, mass of solution = Mass of solute + Mass of solvent
= (36 + 100) g
= 136 g
Therefore, concentration (mass by mass percentage) of the solution
="Mmmmass of solute"/"Mass of solvent"xx100%
=36/136xx100%
= 26.47 %
If you would like to contribute notes or other learning material, please submit them using the button below.
### Shaalaa.com
Solubility of Solution [00:11:32]
S
0% | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.7417765259742737, "perplexity": 3496.79467389485}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2021-17/segments/1618039604430.92/warc/CC-MAIN-20210422191215-20210422221215-00538.warc.gz"} |
https://www.physicsforums.com/threads/sin-x-2-x-4.366207/ | # Homework Help: Sin(x/2) = x/4
1. Dec 30, 2009
### garyng2001hk
1. The problem statement, all variables and given/known data
Solve for x.
2. Relevant equations
Given sin(x/2) = x/4.
3. The attempt at a solution
no idea. the question gives a hint: use graphical method.
2. Dec 30, 2009
### icystrike
You just have to graph y=sin(x/2) and y=x/4 and find the intersection pts.
3. Dec 30, 2009
### alijav
your solution comes as mentioned below
1. draw a curve of x vs sin(x/2)
2. draw a second curve of "x vs x/4"
The solution for x is where both the curves intersect. these are two points
x=0
and
x=3.8
you can find the resultant chart in attached file.
File size:
58.9 KB
Views:
132
4. Jan 3, 2010
### SONOS
Plotting $$\sin(x/2)$$ vs. x and $$x/4$$ is the way to go indeed.
You can plot this another way also.
Rearranging
$$sin(x/2) = x/4$$
to
$$sin(x/2) - x/4 = 0$$
and plotting where the curve crosses the x axis is also another way. It crosses three times. At exactly x=0 and at x equals approximately -3.8 and approximately +3.8.
Close up you see the "zero-crossings" of the x-axis at {-3.8,0,3.8} and if you zoom out you see the curve does not cross at any other points (as far as we can see).
File size:
3.3 KB
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File size:
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159
5. Jan 3, 2010
### SONOS
Here it is from very far away.
File size:
3 KB
Views:
153 | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 1, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9044793248176575, "perplexity": 4197.710885671735}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2018-39/segments/1537267156314.26/warc/CC-MAIN-20180919235858-20180920015858-00309.warc.gz"} |
https://www.qalaxia.com/questions/Find-the-equation-of-the-median-of-a-triangle-Consider | Krishna
0
Step 1: Note down the given vertices and calculate the mid points of the sides.
NOTE: Note down the endpoints (x_1, y_1)and (x_2, y_2) from the given
points. And substitute the values into the midpoint formula.
[FORMULA: The midpoint formula is
M = (\frac{x_1 + x_2}{2}, \frac{y_1 + y_2}{2})
where M is the midpoint of a line segment with endpoints
at (x_1, y_1) and(x_2, y_2).
Step 2: Find the slope of the line between the opposite vertex and each midpoint.
NOTE: m = \frac{y_2 - y_1}{x_2 - x_1}
Step 3: Calculate the equation of the line containing the median from the vertex and the slope.
NOTE: y - y_1 = m(x - x_1)
Step 4:Substitute the known values in the line equation and simplify
Step 5: Do this for the other two medians as well. | {"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8670972585678101, "perplexity": 904.6155933530017}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 20, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2019-09/segments/1550249501174.94/warc/CC-MAIN-20190223122420-20190223144420-00312.warc.gz"} |
https://worldwidescience.org/topicpages/t/tissue+breaking+strength.html | #### Sample records for tissue breaking strength
1. Effect of symmetry breaking on transition strength distributions
International Nuclear Information System (INIS)
Mitchell, G.E.; Shriner, J.F. Jr.
2001-01-01
The quantum numbers of over 100 states in 30 P have been determined from the ground state to 8 MeV. Previous measurements had provided complete spectroscopy in 26 Al. For these N=Z=odd nuclei, states of isospin T=0 and T=1 coexist at all energies. These spectra provide a unique opportunity to test the effect of symmetry breaking (of the approximate symmetry isospin) on the level statistics and on the transition strength distributions. The level statistics are strongly affected by the small symmetry breaking and the transition strength distributions differ from the Porter-Thomas distribution
2. Fibroblast implantation enhances wound healing as indicated by breaking strength determinations
Energy Technology Data Exchange (ETDEWEB)
Krueger, W W; Goepfert, H; Romsdahl, M; Hersen, J; Withers, R H; Jesse, R H
1978-09-01
Irradiation of normal tissues at the dose/time factor employed in the treatment of solid tumors impairs the subsequent healing of surgical wounds made in those tissues. Irreversible radiation damage to regional fibroblasts is one cause of impared healing. This study was conducted to determine whether syngeneic guinea pig fibroblasts is one cause of impared healing. This study was conducted to determine whether syngeneic guinea pig fibroblasts, harvested from tissue culture when injected into irradiated guinea pig skin at the time of wound closure, could improve wound healing. Breaking strength determinations indicate that irradiated wounds demonstrate enhanced wound healing if implanted with fibroblasts.
3. Medullary bone and humeral breaking strength in laying hens
International Nuclear Information System (INIS)
Fleming, R.H.; McCormack, H.A.; McTeir, L.; Whitehead, C.C.
1998-01-01
To test the hypothesis that large amounts of medullary bone in the humeral diaphysis may increase breaking strength, various parameters of bone quality and quantity were examined in two large flocks of hens near end of lay. We conclude that the amount of medullary bone in the humerus of hens during the laying period influences bone strength. This medullary bone may not have any intrinsic strength, but may act by contributing to the fracture resistance of the surrounding cortical bone. Using a quantitative, low dose, radiographic technique, we can predict, from early in the laying period, those birds which will develop large amounts of medullary bone in their humeri by the end of the laying period. The formation of medullary bone in the humeral diaphysis is not at the expense of the surrounding radiographed cortical bone
4. Tissue soldering with biodegradable polymer films: in-vitro investigation of hydration effects on weld strength
Science.gov (United States)
Sorg, Brian S.; Welch, Ashley J.
2001-05-01
Previous work demonstrated increased breaking strengths of tissue repaired with liquid albumin solder reinforced with a biodegradable polymer film compared to unreinforced control specimens. It was hypothesized that the breaking strength increase was due to reinforcement of the liquid solder cohesive strength. Immersion in a moist environment can decrease the adhesion of solder to tissue and negate any strength benefits gained from reinforcement. The purpose of this study was to determine if hydrated specimens repaired with reinforced solder would still be stronger than unreinforced controls. A 50%(w/v) bovine serum albumin solder with 0.5 mg/mL Indocyanine Green dye was used to repair an incision in bovine aorta. The solder was coagulated with 806-nm diode laser light. A poly(DL-lactic- co-glycolic acid) film was used to reinforce the solder (the controls had no reinforcement). The repaired tissues were immersed in phosphate buffered saline for time periods of 1 and 2 days. The breaking strengths of all of the hydrated specimens decreased compared to the acute breaking strengths. However, the reinforced specimens still had larger breaking strengths than the unreinforced controls. These results indicate that reinforcement of a liquid albumin solder may have the potential to improve the breaking strength in a clinical setting.
5. Effect of diclofenac on cyclooxygenase-2 levels and early breaking strength of experimental colonic anastomoses and skin incisions
DEFF Research Database (Denmark)
Klein, M; Krarup, P-M; Burcharth, Jakob
2011-01-01
of diclofenac 4 mg/kg/day on the cyclooxygenase-2 (COX-2) enzyme in the anastomotic tissue and on the breaking strength of anastomotic and incisional wounds. The operation was performed with colonic resection and hand-sewn anastomosis. After 3 days, the rats were sacrificed and the breaking strength and the COX......-2 content of the anastomosis were measured. Results: There was a significantly reduced level of COX-2 in the rats treated with diclofenac (p = 0.001); no significant differences in any of the breaking strength measurements and no significant correlation between COX-2 levels and breaking strength...... of the anastomotic or incisional wounds could be found (p = 0.073 and p = 0.727). Conclusion: This study for the first time showed that a diclofenac dose of 4 mg/kg/24 h was sufficient to reduce the level of COX-2 enzymes in the anastomotic tissue in rats. This inhibition of the inflammatory response did not lead...
6. DNA Double-Strand Break Rejoining in Complex Normal Tissues
International Nuclear Information System (INIS)
Ruebe, Claudia E.; Dong, Xiaorong; Kuehne, Martin; Fricke, Andreas; Kaestner, Lars; Lipp, Peter; Ruebe, Christian
2008-01-01
7. Standard test method for determination of breaking strength of ceramic tiles by three-point loading
CERN Document Server
American Society for Testing and Materials. Philadelphia
2001-01-01
1.1 This test method covers the determination of breaking strength of ceramic tiles by three-point loading. 1.2 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.
8. Planning to break unwanted habits: habit strength moderates implementation intention effects on behaviour change.
Science.gov (United States)
Webb, Thomas L; Sheeran, Paschal; Luszczynska, Aleksandra
2009-09-01
Implementation intention formation promotes effective goal striving and goal attainment. However, little research has investigated whether implementation intentions promote behaviour change when people possess strong antagonistic habits. Experiment 1 developed relatively habitual responses that, after a task switch, had a detrimental impact on task performance. Forming an if-then plan reduced the negative impact of habit on performance. However, the effect of forming implementation intentions was smaller among participants who possessed strong habits as compared to participants who had weaker habits. Experiment 2 provided a field test of the role of habit strength in moderating the relationship between implementation intentions and behaviour in the context of smoking. Implementation intentions reduced smoking among participants with weak or moderate smoking habits, but not among participants with strong smoking habits. In summary, habit strength moderates the effectiveness of if-then plan formation in breaking unwanted habits.
9. The {open_quotes}leak-before-break{close_quotes} applicability in decision support system {open_quotes}strength{close_quotes}
Energy Technology Data Exchange (ETDEWEB)
Torop, V.M.; Orynyak, I.V. [Institute for Problems of Strength, Kiev (Ukraine); Kutovoy, O.L. [Institute of Structure Integrity, Kiev (Ukraine)
1997-04-01
A software decision support system, STRENGTH, for application of leak before break analysis, is described. The background methodology and sample application are outlined. The program allows multioptional computation of loading parameters for different types of defects, and variable properties for metals and welded joints. Structural strength is assessed, and service life predictions are made. The program is used to analyze specific defects identified by nondestructive testing.
10. Increasing break-down strength of the support colomn of high-voltage accelerators
International Nuclear Information System (INIS)
Rezvykh, K.A.; Romanov, V.A.
1981-01-01
Calculation results of strength of electric field of the EG-2.5 electrostatic accelerator for the support colomn with electrodes of circular and elliptical transverse cross sections are presented. Conducted is the choice of constructing the column under the condition that the dimensions of the tank, high-voltage electrode, step between the sections and internal diameter of the colomn electrodes are not changed. The potential at the high-voltage electrode equals 2.5 MV while the average longitudinal gradient of the colomn field equals 1.25 MV/m. The support insulation colomn of the high-voltage accelerator screened by rings with transverse cross section in the form of orientation oval in some accelerators promotes obtaining higher operating voltage and at the same time increase of operation reliability at the rest unchanged dimensions of the plant because the probability of break-down between the support colomn and the tank wall decreases. The latter is especially significant for most high-energy accelerators as well as for accelerators used in national economy [ru
11. Effect of Oil Application, Age, Diet, and Pigmentation on the Tensile Strength and Breaking Point of Hair.
Science.gov (United States)
Kavitha, S; Natarajan, Karthika; Thilagavathi, G; Srinivas, C R
2016-01-01
Hair strength depends on various factors such as nutrition, environmental factors, sunlight, oiling, aging, conditioner, etc. To compare the tensile strength and breaking point of the hair shaft between (1) vegetarian and nonvegetarian. (2) Those who regularly apply and those who do not apply oil. (3) Pigmented and nonpigmented hair, (4) childhood and elderly. Hair fibers were mounted in tensile strength testing machine Zwick/Roell Z010 and gradual force was administered. The elongation of hair fiber in mm and the maximum force required to break the hair strand were recorded for each fiber. Elasticity of the children's hair was more than the elasticity of adult ( P = 0.05) although tensile strength in children hair was not statistically significant (>0.05). Similarly, the tensile strength was more among those who regularly consumed nonvegetarian food but the difference was not statistically significant ( P > 0.05). There was no statistically significant difference in other groups ( P > 0.05). Elasticity in children hair is statistically more than elderly hair although there is no significant change in tensile strength.
12. Validation of freezing tissues and cells for analysis of DNA strand break levels by comet assay
Science.gov (United States)
Jackson, Petra
2013-01-01
The comet analysis of DNA strand break levels in tissues and cells has become a common method of screening for genotoxicity. The large majority of published studies have used fresh tissues and cells processed immediately after collection. However, we have used frozen tissues and cells for more than 10 years, and we believe that freezing samples improve efficiency of the method. We compared DNA strand break levels measured in fresh and frozen bronchoalveolar cells, and lung and liver tissues from mice exposed to the known mutagen methyl methanesulphonate (0, 25, 75, 112.5mg/kg). We used a high-throughput comet protocol with fully automated scoring of DNA strand break levels. The overall results from fresh and frozen samples were in agreement [R 2 = 0.93 for %DNA in tail (%TDNA) and R 2 = 0.78 for tail length (TL)]. A slightly increased %TDNA was observed in lung and liver tissue from vehicle controls; and TL was slightly reduced in bronchoalveolar lavage cells from the high-dose group. In our comet protocol, a small block of tissue designated for comet analysis is frozen immediately at tissue collection and kept deep frozen until rapidly homogenised and embedded in agarose. To demonstrate the feasibility of long-term freezing of samples, we analysed the day-to-day variation of our internal historical negative and positive comet assay controls collected over a 10-year period (1128 observations, 11 batches of frozen untreated and H2O2-treated A549 lung epithelial cells). The H2O2 treatment explained most of the variation 57–77% and the day-to-day variation was only 2–12%. The presented protocol allows analysis of samples collected over longer time span, at different locations, with reduced variation by reducing number of electrophoreses and is suitable for both toxicological and epidemiological studies. The use of frozen tissues; however, requires great care during preparation before analysis, with handling as a major risk factor. PMID:24136994
13. Variation in normal and tumor tissue sensitivity of mice to ionizing radiation-induced DNA strand breaks in vivo
International Nuclear Information System (INIS)
Meyn, R.E.; Jenkins, W.T.
1983-01-01
The efficiency of DNA strand break formation in normal and tumor tissues of mice was measured using the technique of alkaline elution coupled with a microfluorometric determination of DNA. This methodology allowed measurement of the DNA strand breaks produced in tissues irradiated in vivo with doses of radiation comparable to those used in radiotherapy (i.e., 1.0 gray) without the necessity for the cells to be dividing and incorporating radioactive precursors to label the DNA. The results showed that substantial differences existed among various tissues in terms of the amount of DNA strand break damage produced for a given dose of radiation. Of the normal tissues, the most breaks were produced in bone marrow and the least were produced in gut. Furthermore, strand break production was relatively inefficient in the tumor compared to the normal tissues. The efficiency of DNA strand break formation measured in the cells from the tissues irradiated in vitro was much more uniform and considerably greater than that measured in vivo, suggesting that the normal tissues in the animal may be radiobiologically hypoxic
14. Accumulation of DNA Double-Strand Breaks in Normal Tissues After Fractionated Irradiation
International Nuclear Information System (INIS)
Ruebe, Claudia E.; Fricke, Andreas; Wendorf, Juliane; Stuetzel, Annika; Kuehne, Martin; Ong, Mei Fang; Lipp, Peter; Ruebe, Christian
2010-01-01
15. Epithelial rotation is preceded by planar symmetry breaking of actomyosin and protects epithelial tissue from cell deformations.
Science.gov (United States)
Viktorinová, Ivana; Henry, Ian; Tomancak, Pavel
2017-11-01
Symmetry breaking is involved in many developmental processes that form bodies and organs. One of them is the epithelial rotation of developing tubular and acinar organs. However, how epithelial cells move, how they break symmetry to define their common direction, and what function rotational epithelial motions have remains elusive. Here, we identify a dynamic actomyosin network that breaks symmetry at the basal surface of the Drosophila follicle epithelium of acinar-like primitive organs, called egg chambers, and may represent a candidate force-generation mechanism that underlies the unidirectional motion of this epithelial tissue. We provide evidence that the atypical cadherin Fat2, a key planar cell polarity regulator in Drosophila oogenesis, directs and orchestrates transmission of the intracellular actomyosin asymmetry cue onto a tissue plane in order to break planar actomyosin symmetry, facilitate epithelial rotation in the opposite direction, and direct the elongation of follicle cells. In contrast, loss of this rotational motion results in anisotropic non-muscle Myosin II pulses that are disorganized in plane and causes cell deformations in the epithelial tissue of Drosophila eggs. Our work demonstrates that atypical cadherins play an important role in the control of symmetry breaking of cellular mechanics in order to facilitate tissue motion and model epithelial tissue. We propose that their functions may be evolutionarily conserved in tubular/acinar vertebrate organs.
16. Breaking through the strength-ductility trade-off dilemma in an Al-Si-based casting alloy.
Science.gov (United States)
Dang, B; Zhang, X; Chen, Y Z; Chen, C X; Wang, H T; Liu, F
2016-08-09
Al-Si-based casting alloys have a great potential in various industrial applications. Common strengthening strategies on these alloys are accompanied inevitably by sacrifice of ductility, known as strength-ductility trade-off dilemma. Here, we report a simple route by combining rapid solidification (RS) with a post-solidification heat treatment (PHT), i.e. a RS + PHT route, to break through this dilemma using a commercial Al-Si-based casting alloy (A356 alloy) as an example. It is shown that yield strength and elongation to failure of the RS + PHT processed alloy are elevated simultaneously by increasing the cooling rate upon RS, which are not influenced by subsequent T6 heat treatment. Breaking through the dilemma is attributed to the hierarchical microstructure formed by the RS + PHT route, i.e. highly dispersed nanoscale Si particles in Al dendrites and nanoscale Al particles decorated in eutectic Si. Simplicity of the RS + PHT route makes it being suitable for industrial scaling production. The strategy of engineering microstructures offers a general pathway in tailoring mechanical properties of other Al-Si-based alloys. Moreover, the remarkably enhanced ductility of A356 alloy not only permits strengthening further the material by work hardening but also enables possibly conventional solid-state forming of the material, thus extending the applications of such an alloy.
17. Elasticity and breaking strength of synthetic suture materials incubated in various equine physiological and pathological solutions.
Science.gov (United States)
Kearney, C M; Buckley, C T; Jenner, F; Moissonnier, P; Brama, P A J
2014-07-01
Selection of suture material in equine surgery is often based on costs or subjective factors, such as the surgeon's personal experience, rather than objective facts. The amount of objective data available on durability of suture materials with regard to specific equine physiological conditions is limited. To evaluate the effect of various equine physiological and pathological fluids on the rate of degradation of a number of commonly used suture materials. In vitro material testing. Suture materials were exposed in vitro to physiological fluid, followed by biomechanical analysis. Three absorbable suture materials, glycolide/lactide copolymer, polyglactin 910 and polydioxanone were incubated at 37°C for 7, 14 or 28 days in phosphate-buffered saline, equine serum, equine urine and equine peritoneal fluid from an animal with peritonitis. Five strands of each suture material type were tested to failure in a materials testing machine for each time point and each incubation medium. Yield strength, strain and Young's modulus were calculated, analysed and reported. For all suture types, the incubation time had a significant effect on yield strength, percentage elongation and Young's modulus in all culture media (Ptype was also shown significantly to influence changes in each of yield strength, percentage elongation and Young's modulus in all culture media (Ptype of fluid have significant effects on the biomechanical properties of various suture materials. These findings are important for evidence-based selection of suture material in clinical cases. © 2013 EVJ Ltd.
18. Mechanical response tissue analyzer for estimating bone strength
Science.gov (United States)
Arnaud, Sara B.; Steele, Charles; Mauriello, Anthony
1991-01-01
One of the major concerns for extended space flight is weakness of the long bones of the legs, composed primarily of cortical bone, that functions to provide mechanical support. The strength of cortical bone is due to its complex structure, described simplistically as cylinders of parallel osteons composed of layers of mineralized collagen. The reduced mechanical stresses during space flight or immobilization of bone on Earth reduces the mineral content, and changes the components of its matrix and structure so that its strength is reduced. Currently, the established clinical measures of bone strength are indirect. The measures are based on determinations of mineral density by means of radiography, photon absorptiometry, and quantitative computer tomography. While the mineral content of bone is essential to its strength, there is growing awareness of the limitations of the measurement as the sole predictor of fracture risk in metabolic bone diseases, especially limitations of the measurement as the sole predictor of fracture risk in metabolic bone diseases, especially osteoporosis. Other experimental methods in clinical trials that more directly evaluate the physical properties of bone, and do not require exposure to radiation, include ultrasound, acoustic emission, and low-frequency mechanical vibration. The last method can be considered a direct measure of the functional capacity of a long bone since it quantifies the mechanical response to a stimulus delivered directly to the bone. A low frequency vibration induces a response (impedance) curve with a minimum at the resonant frequency, that a few investigators use for the evaluation of the bone. An alternative approach, the method under consideration, is to use the response curve as the basis for determination of the bone bending stiffness EI (E is the intrinsic material property and I is the cross-sectional moment of inertia) and mass, fundamental mechanical properties of bone.
19. Nanomechanical strength mechanisms of hierarchical biological materials and tissues.
Science.gov (United States)
Buehler, Markus J; Ackbarow, Theodor
2008-12-01
Biological protein materials (BPMs), intriguing hierarchical structures formed by assembly of chemical building blocks, are crucial for critical functions of life. The structural details of BPMs are fascinating: They represent a combination of universally found motifs such as alpha-helices or beta-sheets with highly adapted protein structures such as cytoskeletal networks or spider silk nanocomposites. BPMs combine properties like strength and robustness, self-healing ability, adaptability, changeability, evolvability and others into multi-functional materials at a level unmatched in synthetic materials. The ability to achieve these properties depends critically on the particular traits of these materials, first and foremost their hierarchical architecture and seamless integration of material and structure, from nano to macro. Here, we provide a brief review of this field and outline new research directions, along with a review of recent research results in the development of structure-property relationships of biological protein materials exemplified in a study of vimentin intermediate filaments.
20. Bone mineral density (BMD) and computer tomographic measurements of the equine proximal phalanx in correlation with breaking strength.
Science.gov (United States)
Tóth, P; Horváth, C; Ferencz, V; Tóth, B; Váradi, A; Szenci, O; Bodó, G
2013-01-01
Despite the fact that bone mineral density (BMD) is an important fracture risk predictor in human medicine, studies in equine orthopedic research are still lacking. We hypothesized that BMD correlates with bone failure and fatigue fractures of this bone. Thus, the objectives of this study were to measure the structural and mechanical properties of the proximal phalanx with dual energy X-ray absorptiometry (DXA), to correlate the data obtained from DXA and computer tomography (CT) measurements to those obtained by loading pressure examination and to establish representative region of interest (ROI) for in vitro BMD measurements of the equine proximal phalanx for predicting bone failure force. DXA was used to measure the whole bone BMD and additional three ROI sites in 14 equine proximal phalanges. Following evaluation of the bone density, whole bone, cortical width and area in the mid-diaphyseal plane were measured on CT images. Bones were broken using a manually controlled universal bone crusher to measure bone failure force and reevaluated for the site of fractures on follow-up CT images. Compressive load was applied at a constant displacement rate of 2 mm/min until failure, defined as the first clear drop in the load measurement. The lowest BMD was measured at the trabecular region (mean +/- SD: 1.52 +/- 0.12 g/cm2; median: 1.48 g/cm2; range: 1.38-1.83 g/cm2). There was a significant positive linear correlation between trabelcular BMD and the breaking strength (P = 0.023, r = 0.62). The trabecular region of the proximal phalanx appears to be the only significant indicator of failure of strength in vitro. This finding should be reassessed to further reveal the prognostic value of trabecular BMD in an in vivo fracture risk model.
1. The Effect of Egg Yolk Chicken Utilization In Fat Liquoring Process to Tensile Strength, Elongation at Break, Water Absorption and Shank Skin Leather Stitch Tear Strength of Combination Tanning (Chrome – Tannine
Directory of Open Access Journals (Sweden)
Mustakim Mustakim
2012-02-01
Full Text Available The aim of this research were to examine level of egg yolk chicken utilization that effective in fat liquoring process to tensile strength, elongation at break, watter absorptin and stitchtear strength of combination tann (Chrome – tannine of shank skin. The material used were fresh shank skin which seven week old, fresh egg with prserved for not more seven days. Data analyse used in this study was complete randomice desaign (CRD. The research treatment was level of egg yolk utilization that are 5 % (P1, 7,5 % (P2, 10,0 % (P3 and 12,5 % (P4. Each treatment repeated four times, and the control using 6,0 % paradol HISN oil (%age calculated from the weight of wet blue. The result shown that rates of tensile strength of P1, P2, P3, P4 respectively were 67,93, 88,09, 89,31, 70,00 kg/cm2. Elongation at break by 24,5, 29,5, 30,0, 28,0 %. Watter absorption by 181,54, 146,20, 132,81, 132,56 %, and stritchtear strength by 43,00, 63,80, 69,50, 60,98 kg/cm. The utilization level of egg yolk 10 % could produce a better tensile strength and elongation at break, watter absorption and stitchtearstrength. It was suggested for used as fat liquoring agent in tanning process shsnk., skin leather. Keywords : Fat liquoring, Tensile strength, Elongation at break, Watter absorbtion,Stitchtear strength
2. Push-out bond strength of bioceramic materials in a synthetic tissue fluid.
Directory of Open Access Journals (Sweden)
2013-12-01
Full Text Available This study compared the push-out bond strength of EndoSequence Root Repair Material (ERRM and Bioaggregate (BA, new bioceramic materials, to that of mineral trioxide aggregate (MTA after incubation in phosphate-buffered saline (PBS, a synthetic tissue fluid, for either 1 week or 2 months.One-hundred and twenty root sections were filled with ProRoot MTA, BA, or ERRM. Each tested material was then randomly divided into two subgroups (n = 20: root sections were immersed in PBS for 1 week or 2 months. The bond strengths were measured using a universal testing machine. After that, the failure modes were examined with stereomicroscopy and scanning electron microscopy (SEM. The push-out data and failure mode categories were analyzed by two-way ANOVA and chi-square tests, respectively.The bond strength of ERRM was significantly higher than that of BA and MTA at both incubation periods. No significant difference was found between the bond strength of MTA and BA at either 1 week or 2 months. Increasing the incubation time to 2 months resulted in a significant increase in bond strength of all the materials. The failure mode was mainly mixed for MTA and BA, but cohesive for ERRM at both incubation periods.ERRM had significantly higher bond strength to root canal walls compared to MTA and BA. Increasing the incubation time significantly improved the bond strength and bioactive reaction products of all materials.
3. Modelling and Predicting the Breaking Strength and Mass Irregularity of Cotton Rotor-Spun Yarns Containing Cotton Fiber Recovered from Ginning Process by Using Artificial Neural Network Algorithm
Directory of Open Access Journals (Sweden)
Mohsen Shanbeh
2011-01-01
Full Text Available One of the main methods to reduce the production costs is waste recycling which is the most important challenge for the future. Cotton wastes collected from ginning process have desirable properties which could be used during spinning process. The purpose of this study was to develop predictive models of breaking strength and mass irregularity (CV% of cotton waste rotor-spun yarns containing cotton waste collected from ginning process by using the artificial neural network trained with backpropagation algorithm. Artificial neural network models have been developed based on rotor diameter, rotor speed, navel type, opener roller speed, ginning waste proportion and yarn linear density as input parameters. The parameters of artificial neural network model, namely, learning, and momentum rate, number of hidden layers and number of hidden processing elements (neurons were optimized to get the best predictive models. The findings showed that the breaking strength and mass irregularity of rotor spun yarns could be predicted satisfactorily by artificial neural network. The maximum error in predicting the breaking strength and mass irregularity of testing data was 8.34% and 6.65%, respectively.
4. Development of high strength hydroxyapatite for bone tissue regeneration using nanobioactive glass composites
Science.gov (United States)
Shrivastava, Pragya; Dalai, Sridhar; Sudera, Prerna; Sivam, Santosh Param; Vijayalakshmi, S.; Sharma, Pratibha
2013-02-01
With an increasing demand of biocompatible bone substitutes for the treatment of bone diseases and bone tissue regeneration, bioactive glass composites are being tested to improvise the osteoconductive as well as osteoinductive properties. Nanobioactive glass (nBG) composites, having composition of SiO2 70 mol%, CaO 26 mol % and P2O5 4 mol% were prepared by Freeze drying method using PEG-PPG-PEG co-polymer. Polymer addition improves the mechanical strength and porosity of the scaffold of nBG. Nano Bioactive glass composites upon implantation undergo specific reactions leading to the formation of crystalline hydroxyapatite (HA). This is tested in vitro using Simulated Body Fluid (SBF). This high strength hydroxyapatite (HA) layer acts as osteoconductive in cellular environment, by acting as mineral base of bones, onto which new bone cells proliferate leading to new bone formation. Strength of the nBG composites as well as HA is in the range of cortical and cancellous bone, thus proving significant for bone tissue regeneration substitutes.
5. Development of high strength hydroxyapatite for bone tissue regeneration using nanobioactive glass composites
International Nuclear Information System (INIS)
Shrivastava, Pragya; Dalai, Sridhar; Vijayalakshmi, S.; Sudera, Prerna; Sivam, Santosh Param; Sharma, Pratibha
2013-01-01
With an increasing demand of biocompatible bone substitutes for the treatment of bone diseases and bone tissue regeneration, bioactive glass composites are being tested to improvise the osteoconductive as well as osteoinductive properties. Nanobioactive glass (nBG) composites, having composition of SiO 2 70 mol%, CaO 26 mol % and P 2 O 5 4 mol% were prepared by Freeze drying method using PEG-PPG-PEG co-polymer. Polymer addition improves the mechanical strength and porosity of the scaffold of nBG. Nano Bioactive glass composites upon implantation undergo specific reactions leading to the formation of crystalline hydroxyapatite (HA). This is tested in vitro using Simulated Body Fluid (SBF). This high strength hydroxyapatite (HA) layer acts as osteoconductive in cellular environment, by acting as mineral base of bones, onto which new bone cells proliferate leading to new bone formation. Strength of the nBG composites as well as HA is in the range of cortical and cancellous bone, thus proving significant for bone tissue regeneration substitutes.
6. Association of sitting time and breaks in sitting with muscle mass, strength, function, and inflammation in community-dwelling older adults.
Science.gov (United States)
Reid, N; Healy, G N; Gianoudis, J; Formica, M; Gardiner, P A; Eakin, E E; Nowson, C A; Daly, R M
2018-02-26
The mechanisms through which excessive sitting time impacts health are important to understand. This study found that each hour of sitting per day was not associated with physical function, although associations with poor body composition were observed. Reducing sitting time for improved weight management in older adults needs further exploration. To examine the association of sitting time and breaks in sitting time with muscle mass, strength, function, and inflammation in older Australians. Data from the thigh-worn activPAL3™ monitor (7-day continuous wear) was used to derive time spent sitting (hours) and total number of sit-stand transitions per day. Body composition (dual energy X-ray absorptiometry), lower-body muscle strength, function (timed up-and-go [TUG], 4-m gait speed, four square step test, 30-second sit-to-stand), and serum inflammatory markers (interleukin-[IL-6], IL-8, IL-10, tumor necrosis factor-alpha [TNF-α], and adiponectin) were measured. Multiple regression analyses, adjusted for age, sex, ethnicity, education, employment status, marital status, number of prescription medications, smoking status, vitamin D, and stepping time, were used to assess the associations. Data from 123 community-dwelling older adults (aged 65-84 years, 63% female) were used. Total daily sitting time was associated with lower percentage lean mass (β [95%CI], - 1.70% [- 2.30, - 1.10]) and higher total body fat mass (2.92 kg [1.94, 3.30]). More frequent breaks in sitting time were associated with a 45% reduced risk of having pre-sarcopenia (OR = 0.55; 95% CI 0.34, 0.91; model 1), defined as appendicular lean mass divided by BMI. No significant associations were observed for sitting time or breaks in sitting with measures of muscle strength, function, or inflammation. In older community-dwelling adults, greater sitting time was associated with a lower percentage lean mass, while more frequent breaks in sitting time were associated with lower odds of having
7. Genipin crosslinker releasing sutures for improving the mechanical/repair strength of damaged connective tissue.
Science.gov (United States)
Sundararaj, Sharath; Slusarewicz, Paul; Brown, Matt; Hedman, Thomas
2017-11-01
8. Breaking of the SU(4) limit for the Gamow-Teller strength in N{proportional_to}Z nuclei
Energy Technology Data Exchange (ETDEWEB)
2007-12-15
We have performed large-scale shell model calculations of the Gamow-Teller strength distributions in N{proportional_to}Z pf-shell nuclei. These calculations were motivated by the experimental attempts to measure the low-lying GT strength for the even-even N=Z+2 or N=Z-2 nuclei {sup 46}Ti, {sup 50}Cr, {sup 54}Fe and {sup 62}Ge, where a sizable low-energy GT strength could be interpreted as reminiscence of SU(4) symmetry; in the limit of exact SU(4) symmetry the GT{sub -} strength would be concentrated in a single transition to the lowest T=0, J=1{sup +} state in the daughter. We confirm that the SU(4) symmetry is strongly broken by the spin-orbit interaction and by increasing neutron excess. (orig.)
9. Theoretical investigations into the influence of the position of a breaking line on the tensile failure of flat, round, bevel-edged tablets using finite element methodology (FEM) and its practical relevance for industrial tablet strength testing.
Science.gov (United States)
Podczeck, Fridrun; Newton, J Michael; Fromme, Paul
2014-12-30
10. In vitro tendon tissue development from human fibroblasts demonstrates collagen fibril diameter growth associated with a rise in mechanical strength
DEFF Research Database (Denmark)
Herchenhan, Andreas; Bayer, Monika L; Svensson, René B
2013-01-01
Collagen-rich tendons and ligaments are important for joint stability and force transmission, but the capacity to form new tendon is poorly understood. In the present study, we investigated mechanical strength, fibril size, and structure during development of tendon-like tissue from adult human...
11. Application of Quantitative MRI for Brain Tissue Segmentation at 1.5 T and 3.0 T Field Strengths
Science.gov (United States)
West, Janne; Blystad, Ida; Engström, Maria; Warntjes, Jan B. M.; Lundberg, Peter
2013-01-01
Background Brain tissue segmentation of white matter (WM), grey matter (GM), and cerebrospinal fluid (CSF) are important in neuroradiological applications. Quantitative Mri (qMRI) allows segmentation based on physical tissue properties, and the dependencies on MR scanner settings are removed. Brain tissue groups into clusters in the three dimensional space formed by the qMRI parameters R1, R2 and PD, and partial volume voxels are intermediate in this space. The qMRI parameters, however, depend on the main magnetic field strength. Therefore, longitudinal studies can be seriously limited by system upgrades. The aim of this work was to apply one recently described brain tissue segmentation method, based on qMRI, at both 1.5 T and 3.0 T field strengths, and to investigate similarities and differences. Methods In vivo qMRI measurements were performed on 10 healthy subjects using both 1.5 T and 3.0 T MR scanners. The brain tissue segmentation method was applied for both 1.5 T and 3.0 T and volumes of WM, GM, CSF and brain parenchymal fraction (BPF) were calculated on both field strengths. Repeatability was calculated for each scanner and a General Linear Model was used to examine the effect of field strength. Voxel-wise t-tests were also performed to evaluate regional differences. Results Statistically significant differences were found between 1.5 T and 3.0 T for WM, GM, CSF and BPF (p3.0 T. The mean differences between 1.5 T and 3.0 T were -66 mL WM, 40 mL GM, 29 mL CSF and -1.99% BPF. Voxel-wise t-tests revealed regional differences of WM and GM in deep brain structures, cerebellum and brain stem. Conclusions Most of the brain was identically classified at the two field strengths, although some regional differences were observed. PMID:24066153
12. Radiation-induced DNA damage in tumors and normal tissues. III. Oxygen dependence of the formation of strand breaks and DNA-protein crosslinks
International Nuclear Information System (INIS)
Zhang, H.; Wallen, C.A.; Wheeler, K.T.; Joch, C.J.
1995-01-01
13. Self-assembled high-strength hydroxyapatite/graphene oxide/chitosan composite hydrogel for bone tissue engineering.
Science.gov (United States)
Yu, Peng; Bao, Rui-Ying; Shi, Xiao-Jun; Yang, Wei; Yang, Ming-Bo
2017-01-02
Graphene hydrogel has shown greatly potentials in bone tissue engineering recently, but it is relatively weak in the practical use. Here we report a facile method to synthesize high strength composite graphene hydrogel. Graphene oxide (GO), hydroxyapatite (HA) nanoparticles (NPs) and chitosan (CS) self-assemble into a 3-dimensional hydrogel with the assistance of crosslinking agent genipin (GNP) for CS and reducing agent sodium ascorbate (NaVC) for GO simultaneously. The dense and oriented microstructure of the resulted composite gel endows it with high mechanical strength, high fixing capacity of HA and high porosity. These properties together with the good biocompatibility make the ternary composite gel a promising material for bone tissue engineering. Such a simultaneous crosslinking and reduction strategy can also be applied to produce a variety of 3D graphene-polymer based nanocomposites for biomaterials, energy storage materials and adsorbent materials. Copyright © 2016 Elsevier Ltd. All rights reserved.
14. Strengths and weaknesses of EST-based prediction of tissue-specific alternative splicing
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Vingron Martin
2004-09-01
Full Text Available Abstract Background Alternative splicing contributes significantly to the complexity of the human transcriptome and proteome. Computational prediction of alternative splice isoforms are usually based on EST sequences that also allow to approximate the expression pattern of the related transcripts. However, the limited number of tissues represented in the EST data as well as the different cDNA construction protocols may influence the predictive capacity of ESTs to unravel tissue-specifically expressed transcripts. Methods We predict tissue and tumor specific splice isoforms based on the genomic mapping (SpliceNest of the EST consensus sequences and library annotation provided in the GeneNest database. We further ascertain the potentially rare tissue specific transcripts as the ones represented only by ESTs derived from normalized libraries. A subset of the predicted tissue and tumor specific isoforms are then validated via RT-PCR experiments over a spectrum of 40 tissue types. Results Our strategy revealed 427 genes with at least one tissue specific transcript as well as 1120 genes showing tumor specific isoforms. While our experimental evaluation of computationally predicted tissue-specific isoforms revealed a high success rate in confirming the expression of these isoforms in the respective tissue, the strategy frequently failed to detect the expected restricted expression pattern. The analysis of putative lowly expressed transcripts using normalized cDNA libraries suggests that our ability to detect tissue-specific isoforms strongly depends on the expression level of the respective transcript as well as on the sensitivity of the experimental methods. Especially splice isoforms predicted to be disease-specific tend to represent transcripts that are expressed in a set of healthy tissues rather than novel isoforms. Conclusions We propose to combine the computational prediction of alternative splice isoforms with experimental validation for
15. DNA double strand break repair pathway plays a significant role in determining the radiotherapy induced normal tissue toxicity among head-and-neck and breast cancer
International Nuclear Information System (INIS)
Sadashiva, Satish Rao Bola; Mumbrekar, Kamalesh Dattaram; Venkatesh, Goutham Hassan; Fernandes, Donald Jerard; Bejadi, Vadhiraja Manjunath; Kapaettu, Satyamoorthy
2014-01-01
The ability to predict individual risk of radiotherapy induced normal tissue complications prior to the therapy may give an opportunity to personalize the treatment aiming improved therapeutic effect and quality of life. Therefore, predicting the risk of developing acute reactions before the initiation of radiation therapy may serve as a potential biomarker. DNA double-strand break (DSB) induction and its repair kinetics in lymphocytes of Head-and-Neck (n = 183) and Breast cancer (n = 132) patients undergoing chemoradiation or radiation therapy alone were analyzed by performing γ-H2AX foci, neutral comet and a modified neutral filter elution assay. Candidate radioresponsive genes like DNA repair, antioxidant pathway, profibrotic cytokine genes were screened for the common variants for their association with normal tissue toxicity outcome. Patients were stratified as non-over responders (NOR) and over responders (OR) based on their Radiation Therapy Oncology Group grading for normal tissue adverse reactions. Our results suggest that DSB repair plays a major role in the development of normal tissue adverse reactions in H and N and Breast cancer patients. The cellular (γ-H2AX analysis) and SNP analysis may have the potential to be developed into a clinically useful predictive assay for identifying the normal tissue over reactors
16. The Relationship between Intramuscular Adipose Tissue, Functional Mobility, and Strength in Postmenopausal Women with and without Type 2 Diabetes
Directory of Open Access Journals (Sweden)
Janet M. Pritchard
2015-01-01
Full Text Available Objectives. To determine (1 whether intramuscular adipose tissue (IntraMAT differs between women with and without type 2 diabetes and (2 the association between IntraMAT and mobility and strength. Methods. 59 women ≥ 65 years with and without type 2 diabetes were included. A 1-Tesla MRI was used to acquire images of the leg. Timed-up-and-go (TUG and grip strength were measured. Regression was used to determine associations between the following: (1 type 2 diabetes and IntraMAT (covariates: age, ethnicity, BMI, waist : hip ratio, and energy expenditure, (2 IntraMAT and TUG (covariates: diabetes, age, BMI, and energy expenditure, and (3 IntraMAT and grip strength (covariates: diabetes, age, height, and lean mass. Results. Women with diabetes had more IntraMAT. After adjustment, IntraMAT was similar between groups (diabetes mean [SD] = 13.2 [1.4]%, controls 11.8 [1.3]%, P=0.515. IntraMAT was related to TUG and grip strength, but the relationships became nonsignificant after adjustment for covariates (difference/percent IntraMAT [95% CI]: TUG = 0.041 seconds [−0.079–0.161], P=0.498, grip strength = −0.144 kg [−0.335–0.066], P=0.175. Conclusions. IntraMAT alone may not be a clinically important predictor of functional mobility and strength; however, whether losses in functional mobility and strength are promoted by IntraMAT accumulation should be explored.
17. Tissue-engineering with muscle fiber fragments improves the strength of a weak abdominal wall in rats
DEFF Research Database (Denmark)
Jangö, Hanna; Gräs, Søren; Christensen, Lise
2017-01-01
INTRODUCTION AND HYPOTHESIS: Alternative approaches to reinforce the native tissue in patients with pelvic organ prolapse (POP) are needed to improve surgical outcome. Our aims were to develop a weakened abdominal wall in a rat model to mimic the weakened vaginal wall in women with POP and then e...... showed a significantly higher strength than the group with MPEG-PLGA alone (p = 0.034). CONCLUSION: Tissue-engineering with MFFs seeded on a scaffold of biodegradable MPEG-PLGA might be an interesting adjunct to future POP repair.......INTRODUCTION AND HYPOTHESIS: Alternative approaches to reinforce the native tissue in patients with pelvic organ prolapse (POP) are needed to improve surgical outcome. Our aims were to develop a weakened abdominal wall in a rat model to mimic the weakened vaginal wall in women with POP...
18. Peak lean tissue mass accrual precedes changes in bone strength indices at the proximal femur during the pubertal growth spurt.
Science.gov (United States)
Jackowski, Stefan A; Faulkner, Robert A; Farthing, Jonathan P; Kontulainen, Saija A; Beck, Thomas J; Baxter-Jones, Adam D G
2009-06-01
We examined the timing of the age and the magnitude of peak lean tissue mass accrual (PLTV) relative to the age and magnitude of two variables of bone strength [peak cross sectional area velocity (PCSAV), and peak section modulus velocity, (PZV)] at the proximal femur in males and females during the adolescent growth spurt. We hypothesized that the age of PLTV would precede the ages of PCSAV and PZV and that there is a positive relationship between the magnitude of PLTV and both PCSAV and PZV in both genders. 41 males and 42 females aged 8-18 years were selected from the Saskatchewan Pediatric Bone Mineral Accrual Study (1991-2005). Participants' total body lean tissue mass was assessed annually for 6 consecutive years using DXA. Narrow neck and femoral shaft cross sectional areas (CSA) and section modulus (Z) were determined using the hip structural analysis (HSA) program. Participants were aligned by maturational age (years from peak height velocity). Lean tissue mass, CSA, and Z were converted into whole year velocities and the maturational age of peak tissue velocities was determined using a cubic spline curve fitting procedure. A 2 x 3 (gender x tissue) factorial MANOVA with repeated measures was used to test for differences between age of PLTV and the ages of PCSAV and PZV between genders. Multiple regression analyses were used to examine the relationship between PLTV and both PCSAV and PZV. There were no sex differences in the ages at which tissue peaks occurred when aligned by maturational age. There were significant differences between the age of PLTV and both PCSAV and PZV at the narrow neck (p=0.001) and femoral shaft (p=0.03), where the age of PLTV preceded both PCSAV and PZV when pooled by gender. PLTV was a significant predictor of the magnitude of both PCSAV and PZV at all sites (ptheory that muscle development is an important factor in affecting bone strength.
19. The effect of dietary phosphorus level and phytase supplementation on growth performance, bone-breaking strength, and litter phosphorus concentration in broilers.
Science.gov (United States)
Powell, S; Johnston, S; Gaston, L; Southern, L L
2008-05-01
This research was conducted to determine the effects of feeding different P levels with and without phytase supplementation on broiler growth performance, bone-breaking strength (BBS), and litter P concentration. An experiment with 4 trials was conducted with 7,840 Ross x Ross straight-run broilers. For each trial, 1,960 broilers were allotted on d 0 to treatments, with 7 replications each and with 70 broilers per replication. The broilers were fed a 4-period feeding program consisting of starter (0 to 14 d), grower (14 to 32 d), finisher (32 to 41 d), and withdrawal (41 to 50 d) periods. For each trial, the same pen was used continuously for each treatment-replication combination, and the litter was not removed between trials. Broilers were fed a control diet [0.43, 0.40, 0.36, or 0.32% nonphytate P (nPP)] in the starter, grower, finisher, and withdrawal periods, respectively, a low Ca and P (LCaP) diet with a 0.05% reduction in nPP in each period, and these 2 diets supplemented with phytase at 600 phytase units/kg (nPP and Ca were reduced by 0.094% in diets with phytase). Diet did not affect (P > 0.10) broiler performance in the starter or withdrawal periods. Generally, both phytase addition and the LCaP diet decreased some aspects of growth performance during the grower and finisher periods. There was no main effect of phytase on BBS, but BBS was decreased in the broilers fed the LCaP diet with phytase addition (nPP x phytase, P broilers fed the LCaP diet. Total P, soluble P (SP), and reactive soluble P (RSP) were decreased (P litter of broilers fed the LCaP diets. Total P, SP, and RSP were decreased (P litter of broilers fed phytase. These data indicate that phytase supplementation at 600 phytase units/kg reduces growth in some periods, has no effect on BBS, and reduces total P, SP, and RSP in the litter.
20. Fixation Strength of Polyetheretherketone Sheath-and-Bullet Device for Soft Tissue Repair in the Foot and Ankle.
Science.gov (United States)
Christensen, Jay; Fischer, Brian; Nute, Michael; Rizza, Robert
Tendon transfers are often performed in the foot and ankle. Recently, interference screws have been a popular choice owing to their ease of use and fixation strength. Considering the benefits, one disadvantage of such devices is laceration of the soft tissues by the implant threads during placement that potentially weaken the structural integrity of the grafts. A shape memory polyetheretherketone bullet-in-sheath tenodesis device uses circumferential compression, eliminating potential damage from thread rotation and maintaining the soft tissue orientation of the graft. The aim of this study was to determine the pullout strength and failure mode for this device in both a synthetic bone analogue and porcine bone models. Thirteen mature bovine extensor tendons were secured into ten 4.0 × 4.0 × 4.0-cm cubes of 15-pound per cubic foot solid rigid polyurethane foam bone analogue models or 3 porcine femoral condyles using the 5 × 20-mm polyetheretherketone soft tissue anchor. The bullet-in-sheath device demonstrated a mean pullout of 280.84 N in the bone analog models and 419.47 N in the porcine bone models. (p = .001). The bullet-in-sheath design preserved the integrity of the tendon graft, and none of the implants dislodged from their original position. Copyright © 2017 The American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.
1. DNA double-strand break repair of blood lymphocytes and normal tissues analysed in a preclinical mouse model: implications for radiosensitivity testing.
Science.gov (United States)
Rübe, Claudia E; Grudzenski, Saskia; Kühne, Martin; Dong, Xiaorong; Rief, Nicole; Löbrich, Markus; Rübe, Christian
2008-10-15
2. Nbn and atm cooperate in a tissue and developmental stage-specific manner to prevent double strand breaks and apoptosis in developing brain and eye.
Directory of Open Access Journals (Sweden)
Paulo M G Rodrigues
Full Text Available Nibrin (NBN or NBS1 and ATM are key factors for DNA Double Strand Break (DSB signaling and repair. Mutations in NBN or ATM result in Nijmegen Breakage Syndrome and Ataxia telangiectasia. These syndromes share common features such as radiosensitivity, neurological developmental defects and cancer predisposition. However, the functional synergy of Nbn and Atm in different tissues and developmental stages is not yet understood. Here, we show in vivo consequences of conditional inactivation of both genes in neural stem/progenitor cells using Nestin-Cre mice. Genetic inactivation of Atm in the central nervous system of Nbn-deficient mice led to reduced life span and increased DSBs, resulting in increased apoptosis during neural development. Surprisingly, the increase of DSBs and apoptosis was found only in few tissues including cerebellum, ganglionic eminences and lens. In sharp contrast, we showed that apoptosis associated with Nbn deletion was prevented by simultaneous inactivation of Atm in developing retina. Therefore, we propose that Nbn and Atm collaborate to prevent DSB accumulation and apoptosis during development in a tissue- and developmental stage-specific manner.
3. Breaking Bat
Science.gov (United States)
Aguilar, Isaac-Cesar; Kagan, David
2013-01-01
The sight of a broken bat in Major League Baseball can produce anything from a humorous dribbler in the infield to a frightening pointed projectile headed for the stands. Bats usually break at the weakest point, typically in the handle. Breaking happens because the wood gets bent beyond the breaking point due to the wave sent down the bat created…
4. Dynamic breaking of a single gold bond
DEFF Research Database (Denmark)
Pobelov, Ilya V.; Lauritzen, Kasper Primdal; Yoshida, Koji
2017-01-01
While one might assume that the force to break a chemical bond gives a measure of the bond strength, this intuition is misleading. If the force is loaded slowly, thermal fluctuations may break the bond before it is maximally stretched, and the breaking force will be less than the bond can sustain...... of a single Au-Au bond and show that the breaking force is dependent on the loading rate. We probe the temperature and structural dependencies of breaking and suggest that the paradox can be explained by fast breaking of atomic wires and slow breaking of point contacts giving very similar breaking forces....
5. A new stable GIP-Oxyntomodulin hybrid peptide improved bone strength both at the organ and tissue levels in genetically-inherited type 2 diabetes mellitus.
Science.gov (United States)
Mansur, Sity Aishah; Mieczkowska, Aleksandra; Flatt, Peter R; Bouvard, Beatrice; Chappard, Daniel; Irwin, Nigel; Mabilleau, Guillaume
2016-06-01
Obesity and type 2 diabetes mellitus (T2DM) progress worldwide with detrimental effects on several physiological systems including bone tissue mainly by affecting bone quality. Several gut hormones analogues have been proven potent in ameliorating bone quality. In the present study, we used the leptin receptor-deficient db/db mice as a model of obesity and severe T2DM to assess the extent of bone quality alterations at the organ and tissue levels. We also examined the beneficial effects of gut hormone therapy in this model by using a new triple agonist ([d-Ala(2)]GIP-Oxm) active at the GIP, GLP-1 and glucagon receptors. As expected, db/db mice presented with dramatic alterations of bone strength at the organ level associated with deterioration of trabecular and cortical microarchitectures and an augmentation in osteoclast numbers. At the tissue level, these animals presented also with alterations of bone strength (reduced hardness, indentation modulus and dissipated energy) with modifications of tissue mineral distribution, collagen glycation and collagen maturity. The use of [d-Ala(2)]GIP-Oxm considerably improved bone strength at the organ level with modest effects on trabecular microarchitecture. At the tissue level, [d-Ala(2)]GIP-Oxm ameliorated bone strength reductions with positive effects on collagen glycation and collagen maturity. This study provides support for including gut hormone analogues as possible new therapeutic strategies for improving bone quality in bone complications associated to T2DM. Copyright © 2016 Elsevier Inc. All rights reserved.
6. Theoretical effects of fully ductile versus fully brittle behaviors of bone tissue on the strength of the human proximal femur and vertebral body.
Science.gov (United States)
Nawathe, Shashank; Yang, Haisheng; Fields, Aaron J; Bouxsein, Mary L; Keaveny, Tony M
2015-05-01
7. The Break
DEFF Research Database (Denmark)
Strand, Anete Mikkala Camille
2018-01-01
storytelling to enact fruitful breakings of patterns unbecoming. The claim being, that the hamster wheel of Work-life anno 2016 needs reconfiguration and the simple yet fruitful manner by which this is done is through acknowledging the benefits of bodies, spaces and artifacts – and the benefits of actually...... taking a break, discontinuing for a moment in order to continue better, wiser and more at ease. Both within and as part of the daily routines, and – now and then – outside these routines in the majesty of nature with time to explore and redirect the course of life in companionships with fellow man...
8. Inner power, physical strength and existential well-being in daily life: relatives' experiences of receiving soft tissue massage in palliative home care.
Science.gov (United States)
Cronfalk, Berit Seiger; Strang, Peter; Ternestedt, Britt-Marie
2009-08-01
This article explores relatives' experiences of receiving soft tissue massage as a support supplement while caring for a dying family member at home. In palliative home care, relatives play an important role as carers to seriously ill and dying family members. To improve their quality of life, different support strategies are of importance. Complementary methods, such as soft tissue massage have become an appreciated supplement for these patients. However, only few studies focus on relatives experiences of receiving soft tissue massage as a supplemental support. Qualitative design Nineteen relatives received soft tissue massage (hand or foot) nine times (25 minutes) in their homes. Open-ended semi-structured tape-recorded interviews were conducted once per relative after the nine times of massage, using qualitative content analysis. Soft tissue massage gave the relatives' feelings of 'being cared for', 'body vitality' and 'peace of mind'. For a while, they put worries of daily life aside as they just experienced 'being'. During massage, it became apparent that body and mind is constituted of an indestructible completeness. The overarching theme was 'inner power, physical strength and existential well-being in their daily lives'. All relatives experienced soft tissue massage positively, although they were under considerable stress. Soft tissue massage could be an option to comfort and support relatives in palliative home care. In palliative nursing care, soft tissue massage could present a worthy supplement in supporting caring relatives.
9. Tissue
Directory of Open Access Journals (Sweden)
David Morrissey
2012-01-01
Full Text Available Purpose. In vivo gene therapy directed at tissues of mesenchymal origin could potentially augment healing. We aimed to assess the duration and magnitude of transene expression in vivo in mice and ex vivo in human tissues. Methods. Using bioluminescence imaging, plasmid and adenoviral vector-based transgene expression in murine quadriceps in vivo was examined. Temporal control was assessed using a doxycycline-inducible system. An ex vivo model was developed and optimised using murine tissue, and applied in ex vivo human tissue. Results. In vivo plasmid-based transgene expression did not silence in murine muscle, unlike in liver. Although maximum luciferase expression was higher in muscle with adenoviral delivery compared with plasmid, expression reduced over time. The inducible promoter cassette successfully regulated gene expression with maximum levels a factor of 11 greater than baseline. Expression was re-induced to a similar level on a temporal basis. Luciferase expression was readily detected ex vivo in human muscle and tendon. Conclusions. Plasmid constructs resulted in long-term in vivo gene expression in skeletal muscle, in a controllable fashion utilising an inducible promoter in combination with oral agents. Successful plasmid gene transfection in human ex vivo mesenchymal tissue was demonstrated for the first time.
10. The strength of a calcified tissue depends in part on the molecular structure and organization of its constituent mineral crystals in their organic matrix
Science.gov (United States)
Landis, W. J.
1995-01-01
High-voltage electron-microscopic tomographic (3D) studies of the ultrastructural interaction between mineral and organic matrix in a variety of calcified tissues reveal different crystal structural and organizational features in association with their respective organic matrices. In brittle or weak pathologic or ectopic calcifications, including examples of osteogenesis imperfecta, calciphylaxis, calcergy, and dermatomyositis, hydroxyapatite crystals occur in various sizes and shapes and are oriented and aligned with respect to collagen in a manner which is distinct from that found in normal calcified tissues. A model of collagen-mineral interaction is proposed which may account for the observed crystal structures and organization. The results indicate that the ultimate strength, support, and other mechanical properties provided by a calcified tissue are dependent in part upon the molecular structure and arrangement of its constituent mineral crystals within their organic matrix.
11. Breaking away.
Science.gov (United States)
Innes, G M; Sosnow, P L
1995-05-01
While life as hospital employees was comfortable, the lure of independence won out for these two emergency department physicians. Breaking away to develop a new company was not easy, but it's paid off for the entrepreneurs of the Capital Region Emergency Medicine, P.C. Developing an emergency medicine business meant learning all aspects of business: billing services, evaluating legal services, raising capital, and becoming employers. The advantage has been an ability to use profits to improve the moral of staff, an increase in salary, and an overall sense of satisfaction.
12. Brittle stalk 2 encodes a putative glycosylphosphatidylinositol-anchored protein that affects mechanical strength of maize tissues by altering the composition and structure of secondary cell walls.
Science.gov (United States)
Ching, Ada; Dhugga, Kanwarpal S; Appenzeller, Laura; Meeley, Robert; Bourett, Timothy M; Howard, Richard J; Rafalski, Antoni
2006-10-01
A spontaneous maize mutant, brittle stalk-2 (bk2-ref), exhibits dramatically reduced tissue mechanical strength. Reduction in mechanical strength in the stalk tissue was highly correlated with a reduction in the amount of cellulose and an uneven deposition of secondary cell wall material in the subepidermal and perivascular sclerenchyma fibers. Cell wall accounted for two-thirds of the observed reduction in dry matter content per unit length of the mutant stalk in comparison to the wildtype stalk. Although the cell wall composition was significantly altered in the mutant in comparison to the wildtype stalks, no compensation by lignin and cell wall matrix for reduced cellulose amount was observed. We demonstrate that Bk2 encodes a Cobra-like protein that is homologous to the rice Bc1 protein. In the bk2-ref gene, a 1 kb transposon-like element is inserted in the beginning of the second exon, disrupting the open reading frame. The Bk2 gene was expressed in the stalk, husk, root, and leaf tissues, but not in the embryo, endosperm, pollen, silk, or other tissues with comparatively few or no secondary cell wall containing cells. The highest expression was in the isolated vascular bundles. In agreement with its role in secondary wall formation, the expression pattern of the Bk2 gene was very similar to that of the ZmCesA10, ZmCesA11, and ZmCesA12 genes, which are known to be involved in secondary wall formation. We have isolated an independent Mutator-tagged allele of bk2, referred to as bk2-Mu7, the phenotype of which is similar to that of the spontaneous mutant. Our results demonstrate that mutations in the Bk2 gene affect stalk strength in maize by interfering with the deposition of cellulose in the secondary cell wall in fiber cells.
13. The Break
DEFF Research Database (Denmark)
Strand, Anete Mikkala Camille; Larsen, Jens
2015-01-01
the challenges of the million-dollar question is stemming from the ‘bets on the future’ – or what David Boje coins as ‘antenarratives’, (Boje, 2008) that emerged through various reconfiguring story actions, on two different occasions. The paper thus elaborates on two cases of restorying events; One taking place...... that language and the social has been granted too much power on the dispense of the bodily, physical and biological – or in short, in dispense of the material. The break To be or not to be poses the theoretical notion of dis-/continuity (Barad, 2007, 2010) from the quantum approach to storytelling (Strand 2012...... in their use of the communicative platform of Object theatre from the methodology of Material Storytelling (Strand 2012). The Bets on the Future piece discusses the extend to which the cases of using this kind of technologies may provide fruitful ‘bets on the future’ in regard to the million-dollar question...
14. A poly(glycerol sebacate)-coated mesoporous bioactive glass scaffold with adjustable mechanical strength, degradation rate, controlled-release and cell behavior for bone tissue engineering.
Science.gov (United States)
Lin, Dan; Yang, Kai; Tang, Wei; Liu, Yutong; Yuan, Yuan; Liu, Changsheng
2015-07-01
15. Albumin solder covalently bound to a polymer membrane: New approach to improve binding strength in laser tissue soldering in-vitro.
Science.gov (United States)
Hiebl, B; Ascher, L; Luetzow, K; Kratz, K; Gruber, C; Mrowietz, C; Nehring, M E; Lendlein, A; Franke, R-P; Jung, F
2018-01-01
Laser tissue soldering (LTS) based on indocyanine green (ICG)-mediated heat-denaturation of proteins might be a promising alternative technique for micro-suturing, but up to now the problem of too weak shear strength of the solder welds in comparison to sutures is not solved. Earlier reports gave promising results showing that solder supported by carrier materials can enhance the cohesive strength of the liquid solder. In these studies, the solder was applied to the carriers by dip coating. Higher reliability of the connection between the solder and the carrier material is expected when the solder is bound covalently to the carrier material. In the present study a poly(ether imide) (PEI) membrane served as carrier material and ICG-supplemented albumin as solder substrate. The latter was covalently coupled to the carrier membrane under physiological conditions to prevent structural protein changes. As laser source a diode continuous-wave laser emitting at 808 nm with intensities between 250 mW and 1500 mW was utilized. The albumin functionalized carrier membrane was placed onto the tunica media of explanted pig thoracic aortae forming an overlapping area of approximately 0.5×0.5 cm2. All tests were performed in a dry state to prevent laser light absorption by water. Infrared spectroscopy, spectro-photometrical determination of the secondary and primary amine groups after acid orange II staining, contact angle measurements, and atomic force microscopy proved the successful functionalization of the PEI membrane with albumin. A laser power of 450 mW LTS could generate a membrane-blood vessel connection which was characterized by a shear strength of 0.08±0.002 MPa, corresponding to 15% of the tensile strength of the native blood vessel. Theoretically, an overlapping zone of 4.1 mm around the entire circumference of the blood vessel could have provided shear strength of the PEI membrane-blood vessel compound identical to the tensile strength of the native
16. Detection of DNA Double Strand Breaks by γH2AX Does Not Result in 53bp1 Recruitment in Mouse Retinal Tissues
Directory of Open Access Journals (Sweden)
Brigitte Müller
2018-05-01
Full Text Available Gene editing is an attractive potential treatment of inherited retinopathies. However, it often relies on endogenous DNA repair. Retinal DNA repair is incompletely characterized in humans and animal models. We investigated recruitment of the double stranded break (DSB repair complex of γH2AX and 53bp1 in both developing and mature mouse neuroretinas. We evaluated the immunofluorescent retinal expression of these proteins during development (P07-P30 in normal and retinal degeneration models, as well as in potassium bromate induced DSB repair in normal adult (3 months retinal explants. The two murine retinopathy models used had different mutations in Pde6b: the severe rd1 and the milder rd10 models. Compared to normal adult retina, we found increased numbers of γH2AX positive foci in all retinal neurons of the developing retina in both model and control retinas, as well as in wild type untreated retinal explant cultures. In contrast, the 53bp1 staining of the retina differed both in amount and character between cell types at all ages and in all model systems. There was strong pan nuclear staining in ganglion, amacrine, and horizontal cells, and cone photoreceptors, which was attenuated. Rod photoreceptors did not stain unequivocally. In all samples, 53bp1 stained foci only rarely occurred. Co-localization of 53bp1 and γH2AX staining was a very rare event (< 1% of γH2AX foci in the ONL and < 3% in the INL, suggesting the potential for alternate DSB sensing and repair proteins in the murine retina. At a minimum, murine retinal DSB repair does not appear to follow canonical pathways, and our findings suggests further investigation is warranted.
17. Balancing mechanical strength with bioactivity in chitosan-calcium phosphate 3D microsphere scaffolds for bone tissue engineering: air- vs. freeze-drying processes.
Science.gov (United States)
Nguyen, D T; McCanless, J D; Mecwan, M M; Noblett, A P; Haggard, W O; Smith, R A; Bumgardner, J D
2013-01-01
18. Unification of SUSY breaking and GUT breaking
Energy Technology Data Exchange (ETDEWEB)
Kobayashi, Tatsuo [Department of Physics, Hokkaido University,Sapporo 060-0810 (Japan); Omura, Yuji [Department of Physics, Nagoya University,Nagoya 464-8602 (Japan)
2015-02-18
We build explicit supersymmetric unification models where grand unified gauge symmetry breaking and supersymmetry (SUSY) breaking are caused by the same sector. Besides, the SM-charged particles are also predicted by the symmetry breaking sector, and they give the soft SUSY breaking terms through the so-called gauge mediation. We investigate the mass spectrums in an explicit model with SU(5) and additional gauge groups, and discuss its phenomenological aspects. Especially, nonzero A-term and B-term are generated at one-loop level according to the mediation via the vector superfields, so that the electro-weak symmetry breaking and 125 GeV Higgs mass may be achieved by the large B-term and A-term even if the stop mass is around 1 TeV.
19. Duality after supersymmetry breaking
International Nuclear Information System (INIS)
1998-05-01
Starting with two supersymmetric dual theories, we imagine adding a chiral perturbation that breaks supersymmetry dynamically. At low energy we then get two theories with soft supersymmetry-breaking terms that are generated dynamically. With a canonical Kaehler potential, some of the scalars of the ''magnetic'' theory typically have negative mass-squared, and the vector-like symmetry is broken. Since for large supersymmetry breaking the ''electric'' theory becomes ordinary QCD, the two theories are then incompatible. For small supersymmetry breaking, if duality still holds, the magnetic theory analysis implies specific patterns of chiral symmetry breaking in supersymmetric QCD with small soft masses
20. Bubbles and breaking waves
Science.gov (United States)
Thorpe, S. A.
1980-01-01
The physical processes which control the transfer of gases between the atmosphere and oceans or lakes are poorly understood. Clouds of micro-bubbles have been detected below the surface of Loch Ness when the wind is strong enough to cause the waves to break. The rate of transfer of gas into solution from these bubbles is estimated to be significant if repeated on a global scale. We present here further evidence that the bubbles are caused by breaking waves, and discuss the relationship between the mean frequency of wave breaking at a fixed point and the average distance between breaking waves, as might be estimated from an aerial photograph.
1. 'BREAKS' Protocol for Breaking Bad News.
Science.gov (United States)
Narayanan, Vijayakumar; Bista, Bibek; Koshy, Cheriyan
2010-05-01
Information that drastically alters the life world of the patient is termed as bad news. Conveying bad news is a skilled communication, and not at all easy. The amount of truth to be disclosed is subjective. A properly structured and well-orchestrated communication has a positive therapeutic effect. This is a process of negotiation between patient and physician, but physicians often find it difficult due to many reasons. They feel incompetent and are afraid of unleashing a negative reaction from the patient or their relatives. The physician is reminded of his or her own vulnerability to terminal illness, and find themselves powerless over emotional distress. Lack of sufficient training in breaking bad news is a handicap to most physicians and health care workers. Adherence to the principles of client-centered counseling is helpful in attaining this skill. Fundamental insight of the patient is exploited and the bad news is delivered in a structured manner, because the patient is the one who knows what is hurting him most and he is the one who knows how to move forward. Six-step SPIKES protocol is widely used for breaking bad news. In this paper, we put forward another six-step protocol, the BREAKS protocol as a systematic and easy communication strategy for breaking bad news. Development of competence in dealing with difficult situations has positive therapeutic outcome and is a professionally satisfying one.
2. Gauge symmetry breaking
International Nuclear Information System (INIS)
Weinberg, S.
1976-01-01
The problem of how gauge symmetries of the weak interactions get broken is discussed. Some reasons why such a heirarchy of gauge symmetry breaking is needed, the reason gauge heirarchies do not seem to arise in theories of a given and related type, and the implications of theories with dynamical symmetry breaking, which can exhibit a gauge hierarchy
3. Dynamical supersymmetry breaking
International Nuclear Information System (INIS)
Affleck, I.
1985-03-01
Supersymmetry, and in particular, dynamical supersymmetry breaking, offers the hope of a natural solution of the gauge hierarchy problem in grand unification. I briefly review recent work on dynamical supersymmetry breaking in four-dimensional Higgs theories and its application to grand unified model building
4. High-speed scanning ablation of dental hard tissues with a λ = 9.3 μm CO2 laser: adhesion, mechanical strength, heat accumulation, and peripheral thermal damage
OpenAIRE
Nguyen, Daniel; Chang, Kwang; Hedayatollahnajafi, Saba; Staninec, Michal; Chan, Kenneth; Lee, Robert; Fried, Daniel
2011-01-01
CO2 lasers can be operated at high laser pulse repetition rates for the rapid and precise removal of dental decay. Excessive heat accumulation and peripheral thermal damage is a concern when using high pulse repetition rates. Peripheral thermal damage can adversely impact the mechanical strength of the irradiated tissue, particularly for dentin, and reduce the adhesion characteristics of the modified surfaces. The interpulpal temperature rise was recorded using microthermocouples situated at ...
5. Consistency of Trend Break Point Estimator with Underspecified Break Number
Directory of Open Access Journals (Sweden)
Jingjing Yang
2017-01-01
Full Text Available This paper discusses the consistency of trend break point estimators when the number of breaks is underspecified. The consistency of break point estimators in a simple location model with level shifts has been well documented by researchers under various settings, including extensions such as allowing a time trend in the model. Despite the consistency of break point estimators of level shifts, there are few papers on the consistency of trend shift break point estimators in the presence of an underspecified break number. The simulation study and asymptotic analysis in this paper show that the trend shift break point estimator does not converge to the true break points when the break number is underspecified. In the case of two trend shifts, the inconsistency problem worsens if the magnitudes of the breaks are similar and the breaks are either both positive or both negative. The limiting distribution for the trend break point estimator is developed and closely approximates the finite sample performance.
6. Supersymmetry breaking from superstrings
International Nuclear Information System (INIS)
Gaillard, M.K.; Lawrence Berkeley Lab., CA; California Univ., Berkeley
1990-01-01
The gauge hierarchy problem is briefly reviewed and a class of effective field theories obtained from superstrings is described. These are characterized by a clasical symmetry, related to the space-time duality of string theory, that is responsible for the suppression of observable supersymmetry breaking effects. At the quantum level, the symmetry is broken by anomalies that provide the seed of observable supersymmetry breaking, and an acceptably large gauge hierarchy may be generated
7. Supersymmetry breaking from superstrings
International Nuclear Information System (INIS)
Gaillard, M.K.
1990-05-01
The gauge hierarchy problem is briefly reviewed and a class of effective field theories obtained from superstrings is described. These are characterized by a classical symmetry, related to the space-time duality of string theory, that is responsible for the suppression of observable supersymmetry breaking effects. At the quantum level, the symmetry is broken by anomalies that provide the seed of observable supersymmetry breaking, and an acceptably large gauge hierarchy may be generated. 26 refs
8. Evaluation of tensile strength of tissue adhesives and sutures for clear corneal incisions using porcine and bovine eyes, with a novel standardized testing platform
Directory of Open Access Journals (Sweden)
Kaja S
2012-02-01
Full Text Available Simon Kaja, Daryl L Goad, Fatima Ali, Ashley Abraham, R Luke Rebenitsch, Savak Teymoorian, Rohit Krishna, Peter KoulenVision Research Center and Department of Ophthalmology, University of Missouri-Kansas City, School of Medicine, Kansas City, MO, USABackground: Tissue adhesives for ophthalmologic applications were proposed almost 50 years ago, yet to date no adequate tissue glues have been identified that combine strong sealing properties with adequate safety and absence of postsurgical side effects. In recent years, cataract surgeries and Descemet's stripping with endothelial keratoplasty procedures have significantly increased the number of clear corneal incisions performed. One of the obstacles to discovery and development of novel tissue adhesives has been the result of nonstandardized testing of potential tissue glues.Methods: We developed an instrument capable of controlling intraocular pressure in explanted porcine and bovine eyes in order to evaluate sealants, adhesives, and surgical closure methods used in ophthalmic surgery in a controlled, repeatable, and validated fashion. We herein developed and validated our instrument by testing the adhesive properties of cyanoacrylate glue in both porcine and bovine explant eyes.Results: The instrument applied and maintained intraocular pressure through a broad range of physiological intraocular pressures. Cyanoacrylate-based glues showed significantly enhanced sealing properties of clear corneal incisions compared with sutured wounds.Conclusion: This study shows the feasibility of our instrument for reliable and standardized testing of tissue adhesive for ophthalmological surgery.Keywords: manometer, intraocular pressure, applanation tonometry, clear corneal incision, tissue adhesive, ocular surgery
9. The Effect of Tempering on Strength Properties and Seed Coat ...
African Journals Online (AJOL)
The effect of tempering on seed coat adhesion strength and mechanical strength of sorghum and millet grain kernels was investigated at different tempering durations. Tempering reduced the kernel breaking strength and had significant effect on seed coat adhesion strength. Tempering the grain for 60 minutes at ambient ...
10. Strong Electroweak Symmetry Breaking
CERN Document Server
Grinstein, Benjamin
2011-01-01
Models of spontaneous breaking of electroweak symmetry by a strong interaction do not have fine tuning/hierarchy problem. They are conceptually elegant and use the only mechanism of spontaneous breaking of a gauge symmetry that is known to occur in nature. The simplest model, minimal technicolor with extended technicolor interactions, is appealing because one can calculate by scaling up from QCD. But it is ruled out on many counts: inappropriately low quark and lepton masses (or excessive FCNC), bad electroweak data fits, light scalar and vector states, etc. However, nature may not choose the minimal model and then we are stuck: except possibly through lattice simulations, we are unable to compute and test the models. In the LHC era it therefore makes sense to abandon specific models (of strong EW breaking) and concentrate on generic features that may indicate discovery. The Technicolor Straw Man is not a model but a parametrized search strategy inspired by a remarkable generic feature of walking technicolor,...
11. Influence of Nd:YAG laser on the bond strength of self-etching and conventional adhesive systems to dental hard tissues.
Science.gov (United States)
Marimoto, A K; Cunha, L A; Yui, K C K; Huhtala, M F R L; Barcellos, D C; Prakki, A; Gonçalves, S E P
2013-01-01
12. Breaking the silence
DEFF Research Database (Denmark)
Konradsen, Hanne; Kirkevold, Marit; McCallin, Antoinette
2012-01-01
and individual interviews were analyzed using the grounded theory method. The findings revealed that the main concern of the patients was feeling isolated, which was resolved using a process of interactional integration. Interactional integration begins by breaking the silence to enable the progression from...
13. Violent breaking wave impacts
DEFF Research Database (Denmark)
Bredmose, Henrik; Peregrine, D.H.; Bullock, G.N.
2009-01-01
When an ocean wave breaks against a steep-fronted breakwater, sea wall or a similar marine structure, its impact on the structure can be very violent. This paper describes the theoretical studies that, together with field and laboratory investigations, have been carried out in order to gain a bet...
14. Spontaneous symmetry breaking, self-trapping, and Josephson oscillations
CERN Document Server
2013-01-01
This volume collects a a number of contributions on spontaneous symmetry breaking. Current studies in this general field are going ahead at a full speed. The book present review chapters which give an overview on the major break throughs of recent years. It covers a number of different physical settings which are introduced when a nonlinearity is added to the underlying symmetric problems and its strength exceeds a certain critical value. The corresponding loss of symmetry, called spontaneous symmetry breaking, alias self-trapping into asymmetric states is extensively discussed in this book.
15. High-speed scanning ablation of dental hard tissues with a λ = 9.3 μm CO2 laser: adhesion, mechanical strength, heat accumulation, and peripheral thermal damage
Science.gov (United States)
Nguyen, Daniel; Chang, Kwang; Hedayatollahnajafi, Saba; Staninec, Michal; Chan, Kenneth; Lee, Robert; Fried, Daniel
2011-07-01
CO2 lasers can be operated at high laser pulse repetition rates for the rapid and precise removal of dental decay. Excessive heat accumulation and peripheral thermal damage is a concern when using high pulse repetition rates. Peripheral thermal damage can adversely impact the mechanical strength of the irradiated tissue, particularly for dentin, and reduce the adhesion characteristics of the modified surfaces. The interpulpal temperature rise was recorded using microthermocouples situated at the roof of the pulp chamber on teeth that were occlusally ablated using a rapidly-scanned CO2 laser operating at 9.3 μm with a pulse duration of 10 to 15 μs and repetition rate of 300 Hz over a 2 min time course. The adhesion strength of laser treated enamel and dentin surfaces was measured for various laser scanning parameters with and without post-ablation acid etching using the single-plane shear test. The mechanical strength of laser-ablated dentin surfaces were determined via the four-point bend test and compared to control samples prepared with 320 grit wet sand paper to simulate conventional preparations. Thermocouple measurements indicated that the temperature remained below ambient temperature if water-cooling was used. There was no discoloration of either dentin or enamel laser treated surfaces, the surfaces were uniformly ablated, and there were no cracks visible. Four-point bend tests yielded mean mechanical strengths of 18.2 N (s.d. = 4.6) for ablated dentin and 18.1 N (s.d. = 2.7) for control (p > 0.05). Shear tests yielded mean bond strengths approaching 30 MPa for both enamel and dentin under certain irradiation conditions. These values were slightly lower than nonirradiated acid-etched control samples. Additional studies are needed to determine if the slightly lower bond strength than the acid-etched control samples is clinically significant. These measurements demonstrate that enamel and dentin surfaces can be rapidly ablated by CO2 lasers with minimal
16. Routinizing Breaking News
DEFF Research Database (Denmark)
Hartley, Jannie Møller
2011-01-01
This chapter revisits seminal theoretical categorizations of news proposed three decades earlier by US sociologist Gaye Tuchman. By exploring the definition of ”breaking news” in the contemporary online newsrooms of three Danish news organisations, the author offers us a long overdue re-theorizat......-theorization of journalistic practice in the online context and helpfully explores well-evidenced limitations to online news production, such as the relationship between original reporting and the use of ”shovelware.”......This chapter revisits seminal theoretical categorizations of news proposed three decades earlier by US sociologist Gaye Tuchman. By exploring the definition of ”breaking news” in the contemporary online newsrooms of three Danish news organisations, the author offers us a long overdue re...
DEFF Research Database (Denmark)
Hartley, Jannie Møller
The aim of the paper is to make explicit how the different categories are applied in the online newsroom and thus how new categories can be seen as positioning strategies in the form of radicalisations of already existing categories. Thus field theory provides us with tools to analyse how online...... journalists are using the categorisations to create hierarchies within the journalistic field in order to position themselves as specialists in what Tuchman has called developing news, aiming and striving for what today is know as breaking news and the “exclusive scoop,” as the trademark of online journalism...... in a media environment where immediacy rules (Domingo 2008a). Following this research the primary focus of this paper is the category breaking news and Tuchmans developing news, but as they are all connected the analysis will also draw upon the other categories in Tuchmans typology. The theoretical framework...
18. Predicting appointment breaking.
Science.gov (United States)
Bean, A G; Talaga, J
1995-01-01
The goal of physician referral services is to schedule appointments, but if too many patients fail to show up, the value of the service will be compromised. The authors found that appointment breaking can be predicted by the number of days to the scheduled appointment, the doctor's specialty, and the patient's age and gender. They also offer specific suggestions for modifying the marketing mix to reduce the incidence of no-shows.
19. Single sector supersymmetry breaking
International Nuclear Information System (INIS)
Luty, Markus A.; Terning, John
1999-01-01
We review recent work on realistic models that break supersymmetry dynamically and give rise to composite quarks and leptons, all in a single sector. These models have a completely natural suppression of flavor-changing neutral currents, and the hierarchy of Yukawa couplings is explained by the dimensionality of composite states. The generic signatures are unification of scalar masses with different quantum numbers at the compositeness scale, and lighter gaugino, Higgsino, and third-generation sfermion masses
20. Dual descriptions of supersymmetry breaking
International Nuclear Information System (INIS)
Intrilligator, K.; Thomas, S.
1996-08-01
Dynamical supersymmetry breaking is considered in models which admit descriptions in terms of electric, confined, or magnetic degrees of freedom in various limits. In this way, a variety of seemingly different theories which break supersymmetry are actually interrelated by confinement or duality. Specific examples are given in which there are two dual descriptions of the supersymmetry breaking ground state
1. BOOK REVIEW: Symmetry Breaking
Science.gov (United States)
Ryder, L. H.
2005-11-01
One of the most fruitful and enduring advances in theoretical physics during the last half century has been the development of the role played by symmetries. One needs only to consider SU(3) and the classification of elementary particles, the Yang Mills enlargement of Maxwell's electrodynamics to the symmetry group SU(2), and indeed the tremendous activity surrounding the discovery of parity violation in the weak interactions in the late 1950s. This last example is one of a broken symmetry, though the symmetry in question is a discrete one. It was clear to Gell-Mann, who first clarified the role of SU(3) in particle physics, that this symmetry was not exact. If it had been, it would have been much easier to discover; for example, the proton, neutron, Σ, Λ and Ξ particles would all have had the same mass. For many years the SU(3) symmetry breaking was assigned a mathematical form, but the importance of this formulation fell away when the quark model began to be taken seriously; the reason the SU(3) symmetry was not exact was simply that the (three, in those days) quarks had different masses. At the same time, and in a different context, symmetry breaking of a different type was being investigated. This went by the name of spontaneous symmetry breaking' and its characteristic was that the ground state of a given system was not invariant under the symmetry transformation, though the interactions (the Hamiltonian, in effect) was. A classic example is ferromagnetism. In a ferromagnet the atomic spins are aligned in one direction only—this is the ground state of the system. It is clearly not invariant under a rotation, for that would change the ground state into a (similar but) different one, with the spins aligned in a different direction; this is the phenomenon of a degenerate vacuum. The contribution of the spin interaction, s1.s2, to the Hamiltonian, however, is actually invariant under rotations. As Coleman remarked, a little man living in a ferromagnet would
2. Inertial Symmetry Breaking
Energy Technology Data Exchange (ETDEWEB)
Hill, Christopher T.
2018-03-19
We review and expand upon recent work demonstrating that Weyl invariant theories can be broken "inertially," which does not depend upon a potential. This can be understood in a general way by the "current algebra" of these theories, independently of specific Lagrangians. Maintaining the exact Weyl invariance in a renormalized quantum theory can be accomplished by renormalization conditions that refer back to the VEV's of fields in the action. We illustrate the computation of a Weyl invariant Coleman-Weinberg potential that breaks a U(1) symmetry together,with scale invariance.
3. Break the Pattern!
DEFF Research Database (Denmark)
Hasse, Cathrine; Trentemøller, Stine
Break the Pattern! A critical enquiry into three scientific workplace cultures: Hercules, Caretakers and Worker Bees is the third publication of the international three year long project "Understanding Puzzles in the Gendered European Map" (UPGEM). By contrasting empirical findings from academic ...... (physics in culture) and discuss how physics as and in culture influence the perception of science, of work and family life, of the interplay between religion and science as well as how physics as culture can either hinder or promote the career of female scientists....
4. Breaking the Waves
DEFF Research Database (Denmark)
Christensen, Poul Rind; Kirketerp, Anne
2006-01-01
The paper shortly reveals the history of a small school - the KaosPilots - dedicated to educate young people to carriers as entrepreneurs. In this contribution we want to explore how the KaosPilots managed to break the waves of institutionalised concepts and practices of teaching entrepreneurship....... Following the so-called 'Dogma' concept developed by Danish filmmakers, this contribution aim to explore the key elements making up the recipes guiding the entrepreneurship training program exercised by the school. Key factors forming a community of learning practice are outlined as well as the critical...... pedagogical elements on which the education in entrepreneurship rests....
5. Acute Ultraviolet Radiation Perturbs Epithelialization but not the Biomechanical Strength of Full-thickness Cutaneous Wounds
DEFF Research Database (Denmark)
Danielsen, Patricia L; Lerche, Catharina M; Wulf, Hans Christian
2016-01-01
SED, 3 SED and 5 SED. Twenty-four hours after UV irradiation, inflammation was quantified by skin reflectance (erythema) and myeloperoxidase (MPO) tissue levels, and two 6 mm full-thickness excisional wounds and one 3 cm incisional wound were inflicted. Epidermal hyperplasia was assessed...... (P epithelial coverage decreased (P = 0.024) by increasing the UVR dose, whereas there was no significant difference (P = 0.765) in wound MPO levels. Neither wound width (P = 0.850) nor breaking strength (P...... = 0.320) differed among the groups. Solar-simulated UVR 24 h before wounding impaired epithelialization but was not detrimental for surgical incisional wound healing....
6. More dynamical supersymmetry breaking
International Nuclear Information System (INIS)
Csaki, C.; Randall, L.; Skiba, W.
1996-01-01
In this paper we introduce a new class of theories which dynamically break supersymmetry based on the gauge group SU(n) x SU(3) x U(1) for even n. These theories are interesting in that no dynamical superpotential is generated in the absence of perturbations. For the example SU(4) x SU(3) x U(1) we explicitly demonstrate that all flat directions can be lifted through a renormalizable superpotential and that supersymmetry is dynamically broken. We derive the exact superpotential for this theory, which exhibits new and interesting dynamical phenomena. For example, modifications to classical constraints can be field dependent. We also consider the generalization to SU(n) x SU(3) x U(1) models (with even n>4). We present a renormalizable superpotential which lifts all flat directions. Because SU(3) is not confining in the absence of perturbations, the analysis of supersymmetry breaking is very different in these theories from the n=4 example. When the SU(n) gauge group confines, the Yukawa couplings drive the SU(3) theory into a regime with a dynamically generated superpotential. By considering a simplified version of these theories we argue that supersymmetry is probably broken. (orig.)
7. Bootstrap Dynamical Symmetry Breaking
Directory of Open Access Journals (Sweden)
Wei-Shu Hou
2013-01-01
Full Text Available Despite the emergence of a 125 GeV Higgs-like particle at the LHC, we explore the possibility of dynamical electroweak symmetry breaking by strong Yukawa coupling of very heavy new chiral quarks Q . Taking the 125 GeV object to be a dilaton with suppressed couplings, we note that the Goldstone bosons G exist as longitudinal modes V L of the weak bosons and would couple to Q with Yukawa coupling λ Q . With m Q ≳ 700 GeV from LHC, the strong λ Q ≳ 4 could lead to deeply bound Q Q ¯ states. We postulate that the leading “collapsed state,” the color-singlet (heavy isotriplet, pseudoscalar Q Q ¯ meson π 1 , is G itself, and a gap equation without Higgs is constructed. Dynamical symmetry breaking is affected via strong λ Q , generating m Q while self-consistently justifying treating G as massless in the loop, hence, “bootstrap,” Solving such a gap equation, we find that m Q should be several TeV, or λ Q ≳ 4 π , and would become much heavier if there is a light Higgs boson. For such heavy chiral quarks, we find analogy with the π − N system, by which we conjecture the possible annihilation phenomena of Q Q ¯ → n V L with high multiplicity, the search of which might be aided by Yukawa-bound Q Q ¯ resonances.
8. Using Appreciative Intelligence for Ice-Breaking: A New Design
Science.gov (United States)
Verma, Neena; Pathak, Anil Anand
2011-01-01
Purpose: The purpose of this paper is to highlight the importance of applying appreciative intelligence and appreciative inquiry concepts to design a possibly new model of ice-breaking, which is strengths-based and very often used in any training in general and team building training in particular. Design/methodology/approach: The design has…
9. Breaking of ocean surface waves
International Nuclear Information System (INIS)
Babanin, A.V.
2009-01-01
Wind-generated waves are the most prominent feature of the ocean surface, and so are breaking waves manifested by the appearance of sporadic whitecaps. Such breaking represents one of the most interesting and most challenging problems for both fluid mechanics and physical oceanography. It is an intermittent random process, very fast by comparison with other processes in the wave breaking on the water surface is not continuous, but its role in maintaining the energy balance within the continuous wind-wave field is critical. Ocean wave breaking also plays the primary role in the air-sea exchange of momentum, mass and heat, and it is of significant importance for ocean remote sensing, coastal and maritime engineering, navigation and other practical applications. Understanding the wave breaking its occurrence, the breaking rates and even ability to describe its onset has been hindered for decades by the strong non-linearity of the process, together with its irregular and ferocious nature. Recently, this knowledge has significantly advanced, and the review paper is an attempt to summarise the facts into a consistent, albeit still incomplete picture of the phenomenon. In the paper, variety of definitions related to the were breaking are discussed and formulated and methods for breaking detection and measurements are examined. Most of attention is dedicated to the research of wave breaking probability and severity. Experimental, observational, numerical and statistical approaches and their outcomes are reviewed. Present state of the wave-breaking research and knowledge is analysed and main outstanding problems are outlined (Authors)
10. Toughening elastomers with sacrificial bonds and watching them break.
Science.gov (United States)
Ducrot, Etienne; Chen, Yulan; Bulters, Markus; Sijbesma, Rint P; Creton, Costantino
2014-04-11
Elastomers are widely used because of their large-strain reversible deformability. Most unfilled elastomers suffer from a poor mechanical strength, which limits their use. Using sacrificial bonds, we show how brittle, unfilled elastomers can be strongly reinforced in stiffness and toughness (up to 4 megapascals and 9 kilojoules per square meter) by introducing a variable proportion of isotropically prestretched chains that can break and dissipate energy before the material fails. Chemoluminescent cross-linking molecules, which emit light as they break, map in real time where and when many of these internal bonds break ahead of a propagating crack. The simple methodology that we use to introduce sacrificial bonds, combined with the mapping of where bonds break, has the potential to stimulate the development of new classes of unfilled tough elastomers and better molecular models of the fracture of soft materials.
11. Small break loss of coolant accidents: Bottom and side break
International Nuclear Information System (INIS)
Hardy, P.G.; Richter, H.J.
1987-01-01
A LOCA can be caused, e.g. by a small break in the primary cooling system. The rate of fluid escaping through such a break will define the time until the core will be uncovered. Therefore the prediction of fluid loss and pressure transient is of major importance to plan for timely action in response to such an event. Stratification of the two phases might be present upstream of the break, thus, the location of the break relative to the vapor-liquid interface and the overall upstream fluid conditions are relevant for the calculation of fluid loss. Experimental results and analyses are presented here for small breaks at the bottom or at the side of a small pressure vessel. It was found that in such a case the onset of the so-called ''vapor pull through'' is important but swelling at sufficient depressurization rates of the liquid due to flashing is also of significance. It was also discovered that in the bottom break the flow rate is strongly dependent on the break entrance quality of the vapour-liquid mixture. The side break can be treated similarly to the bottom break if the interface level is above the break. The analyses developed on the basis of experimental observations showed reasonable agreement of predicted and measured pressure transients. It was possible to calculate the changing interface level and mixture void fraction history in a way compatible with the behavior observed during the experiments. Even though the experiments were performed at low pressures, this work should help to get a better understanding of physical phenomena occurring in a full scale small break LOCA. (orig./HP)
12. Electroweak breaking in supersymmetric models
CERN Document Server
Ibáñez, L E
1992-01-01
We discuss the mechanism for electroweak symmetry breaking in supersymmetric versions of the standard model. After briefly reviewing the possible sources of supersymmetry breaking, we show how the required pattern of symmetry breaking can automatically result from the structure of quantum corrections in the theory. We demonstrate that this radiative breaking mechanism works well for a heavy top quark and can be combined in unified versions of the theory with excellent predictions for the running couplings of the model. (To be published in Perspectives in Higgs Physics'', G. Kane editor.)
13. Effects of Whey, Soy or Leucine Supplementation with 12 Weeks of Resistance Training on Strength, Body Composition, and Skeletal Muscle and Adipose Tissue Histological Attributes in College-Aged Males
Directory of Open Access Journals (Sweden)
C. Brooks Mobley
2017-09-01
Full Text Available We sought to determine the effects of L-leucine (LEU or different protein supplements standardized to LEU (~3.0 g/serving on changes in body composition, strength, and histological attributes in skeletal muscle and adipose tissue. Seventy-five untrained, college-aged males (mean ± standard error of the mean (SE; age = 21 ± 1 years, body mass = 79.2 ± 0.3 kg were randomly assigned to an isocaloric, lipid-, and organoleptically-matched maltodextrin placebo (PLA, n = 15, LEU (n = 14, whey protein concentrate (WPC, n = 17, whey protein hydrolysate (WPH, n = 14, or soy protein concentrate (SPC, n = 15 group. Participants performed whole-body resistance training three days per week for 12 weeks while consuming supplements twice daily. Skeletal muscle and subcutaneous (SQ fat biopsies were obtained at baseline (T1 and ~72 h following the last day of training (T39. Tissue samples were analyzed for changes in type I and II fiber cross sectional area (CSA, non-fiber specific satellite cell count, and SQ adipocyte CSA. On average, all supplement groups including PLA exhibited similar training volumes and experienced statistically similar increases in total body skeletal muscle mass determined by dual X-ray absorptiometry (+2.2 kg; time p = 0.024 and type I and II fiber CSA increases (+394 μm2 and +927 μm2; time p < 0.001 and 0.024, respectively. Notably, all groups reported increasing Calorie intakes ~600–800 kcal/day from T1 to T39 (time p < 0.001, and all groups consumed at least 1.1 g/kg/day of protein at T1 and 1.3 g/kg/day at T39. There was a training, but no supplementation, effect regarding the reduction in SQ adipocyte CSA (−210 μm2; time p = 0.001. Interestingly, satellite cell counts within the WPC (p < 0.05 and WPH (p < 0.05 groups were greater at T39 relative to T1. In summary, LEU or protein supplementation (standardized to LEU content does not provide added benefit in increasing whole-body skeletal muscle mass or strength above PLA
14. Protein-enriched diet, with the use of lean red meat, combined with progressive resistance training enhances lean tissue mass and muscle strength and reduces circulating IL-6 concentrations in elderly women: a cluster randomized controlled trial.
Science.gov (United States)
Daly, Robin M; O'Connell, Stella L; Mundell, Niamh L; Grimes, Carley A; Dunstan, David W; Nowson, Caryl A
2014-04-01
Physical inactivity, inadequate dietary protein, and low-grade systemic inflammation contribute to age-related muscle loss, impaired function, and disability. We assessed the effects of progressive resistance training (PRT) combined with a protein-enriched diet facilitated through lean red meat on lean tissue mass (LTM), muscle size, strength and function, circulating inflammatory markers, blood pressure, and lipids in elderly women. In a 4-mo cluster randomized controlled trial, 100 women aged 60-90 y who were residing in 15 retirement villages were allocated to receive PRT with lean red meat (∼160 g cooked) to be consumed 6 d/wk [resistance training plus lean red meat (RT+Meat) group; n = 53] or control PRT [1 serving pasta or rice/d; control resistance training (CRT) group; n = 47)]. All women undertook PRT 2 times/wk and received 1000 IU vitamin D3/d. The mean (± SD) protein intake was greater in the RT+Meat group than in the CRT group throughout the study (1.3 ± 0.3 compared with 1.1 ± 0.3 g · kg⁻¹ · d⁻¹, respectively; P < 0.05). The RT+Meat group experienced greater gains in total body LTM (0.45 kg; 95% CI: 0.07, 0.84 kg), leg LTM (0.22 kg; 95% CI: 0.02, 0.42 kg), and muscle strength (18%; 95% CI: 0.03, 0.34) than did the CRT group (all P < 0.05). The RT+Meat group also experienced a 10% greater increase in serum insulin-like growth factor I (P < 0.05) and a 16% greater reduction in the proinflammatory marker interleukin-6 (IL-6) (P < 0.05) after 4 mo. There were no between-group differences for the change in blood lipids or blood pressure. A protein-enriched diet equivalent to ∼1.3 g · kg⁻¹ · d⁻¹ achieved through lean red meat is safe and effective for enhancing the effects of PRT on LTM and muscle strength and reducing circulating IL-6 concentrations in elderly women. This trial was registered at the Australian Clinical Trials Registry as ACTRN12609000223235.
15. R-parity breaking phenomenology
International Nuclear Information System (INIS)
Vissani, F.
1996-02-01
We review various features of the R-parity breaking phenomenology, with particular attention to the low energy observables, and to the patterns of the R-parity breaking interactions that arise in Grand Unified models. (author). 22 refs, 1 fig., 3 tabs
16. STRESS FRACTURE OF THE ULNA IN A BREAK-DANCER
Directory of Open Access Journals (Sweden)
Yu-Hsu Chen
2008-12-01
Full Text Available Break dancing is a popular activity in teenagers and is associated with severe trauma to bones and tissues. We report the first known case of a break dancer with an ulnar stress fracture. Such injuries occur in a variety of sports due to substantial stress on the ulna and repetitive excessive rotation of the forearm. In this study we describe a patient who experienced an ulnar stress fracture during break dancing training. The diagnosis was established by history and physical examination. Initial radiographic findings were negative. However, radiographs taken 3 months after initial presented revealed callus formation over the ulnar shaft. This suggested that readjustment is required in break dancing training protocols. It is important to increase awareness of this injury among physicians to expedite the diagnosis and to prevent the possibility of conversion to an overt fracture in the future
17. Inflation from supersymmetry breaking
Energy Technology Data Exchange (ETDEWEB)
Antoniadis, I. [UMR CNRS 7589 Sorbonne Universites, UPMC Paris 6, LPTHE, Paris (France); University of Bern, Albert Einstein Center, Institute for Theoretical Physics, Bern (Switzerland); Chatrabhuti, A.; Isono, H.; Knoops, R. [Chulalongkorn University, Department of Physics, Faculty of Science, Pathumwan, Bangkok (Thailand)
2017-11-15
We explore the possibility that inflation is driven by supersymmetry breaking with the superpartner of the goldstino (sgoldstino) playing the role of the inflaton. Moreover, we impose an R-symmetry that allows one to satisfy easily the slow-roll conditions, avoiding the so-called η-problem, and leads to two different classes of small-field inflation models; they are characterised by an inflationary plateau around the maximum of the scalar potential, where R-symmetry is either restored or spontaneously broken, with the inflaton rolling down to a minimum describing the present phase of our Universe. To avoid the Goldstone boson and be left with a single (real) scalar field (the inflaton), R-symmetry is gauged with the corresponding gauge boson becoming massive. This framework generalises a model studied recently by the present authors, with the inflaton identified by the string dilaton and R-symmetry together with supersymmetry restored at weak coupling, at infinity of the dilaton potential. The presence of the D-term allows a tuning of the vacuum energy at the minimum. The proposed models agree with cosmological observations and predict a tensor-to-scalar ratio of primordial perturbations 10{sup -9}
18. Symmetry breaking by bifundamentals
Science.gov (United States)
Schellekens, A. N.
2018-03-01
We derive all possible symmetry breaking patterns for all possible Higgs fields that can occur in intersecting brane models: bifundamentals and rank-2 tensors. This is a field-theoretic problem that was already partially solved in 1973 by Ling-Fong Li [1]. In that paper the solution was given for rank-2 tensors of orthogonal and unitary group, and U (N )×U (M ) and O (N )×O (M ) bifundamentals. We extend this first of all to symplectic groups. When formulated correctly, this turns out to be straightforward generalization of the previous results from real and complex numbers to quaternions. The extension to mixed bifundamentals is more challenging and interesting. The scalar potential has up to six real parameters. Its minima or saddle points are described by block-diagonal matrices built out of K blocks of size p ×q . Here p =q =1 for the solutions of Ling-Fong Li, and the number of possibilities for p ×q is equal to the number of real parameters in the potential, minus 1. The maximum block size is p ×q =2 ×4 . Different blocks cannot be combined, and the true minimum occurs for one choice of basic block, and for either K =1 or K maximal, depending on the parameter values.
19. Symmetry and symmetry breaking
International Nuclear Information System (INIS)
Balian, R.; Lambert, D.; Brack, A.; Lachieze-Rey, M.; Emery, E.; Cohen-Tannoudji, G.; Sacquin, Y.
1999-01-01
The symmetry concept is a powerful tool for our understanding of the world. It allows a reduction of the volume of information needed to apprehend a subject thoroughly. Moreover this concept does not belong to a particular field, it is involved in the exact sciences but also in artistic matters. Living beings are characterized by a particular asymmetry: the chiral asymmetry. Although this asymmetry is visible in whole organisms, it seems it comes from some molecules that life always produce in one chirality. The weak interaction presents also the chiral asymmetry. The mass of particles comes from the breaking of a fundamental symmetry and the void could be defined as the medium showing as many symmetries as possible. The texts put together in this book show to a great extent how symmetry goes far beyond purely geometrical considerations. Different aspects of symmetry ideas are considered in the following fields: the states of matter, mathematics, biology, the laws of Nature, quantum physics, the universe, and the art of music. (A.C.)
20. Experimental and simulated strength of spot welds
DEFF Research Database (Denmark)
Nielsen, Chris Valentin; Bennedbæk, Rune A.K.; Larsen, Morten B.
2014-01-01
Weld strength testing of single spots in DP600 steel is presented for the three typical testing procedures, i.e. tensile-shear, cross-tension and peel testing. Spot welds are performed at two sets of welding parameters and strength testing under these conditions is presented by load......-elongation curves revealing the maximum load and the elongation at break. Welding and strength testing is simulated by SORPAS® 3D, which allows the two processes to be prepared in a combined simulation, such that the simulated welding properties are naturally applied to the simulation of strength testing. Besides...... the size and shape of the weld nugget, these properties include the new strength of the material in the weld and the heat affected zone based on the predicted hardness resulting from microstructural phase changes simulated during cooling of the weld before strength testing. Comparisons between overall...
1. Simulation of breaking waves using the high-order spectral method with laboratory experiments: Wave-breaking onset
Science.gov (United States)
Seiffert, Betsy R.; Ducrozet, Guillaume; Bonnefoy, Félicien
2017-11-01
waves provides a wide range of breaking-wave strengths, types and scales for validation of the model. A comparison of calculations made using HOS-NWT with experimental measurements show that the model is successful at predicting the occurrence of wave breaking, as well as accurately calculating breaking onset time and location. Although the current study is limited to a unidirectional wave field, the success of the wave-breaking model presented provides the basis for application of the model in a multidirectional wave field. By including wave breaking onset with the addition of an appropriate energy dissipation model into HOS-NWT, we can increase the application range of the model, as well as decrease the occurrence of numerical instabilities that are associated with breaking waves in a potential flow solver. An accurate description of the wave field is useful for predicting the dynamic response of offshore vessels and marine renewable energy devices, predicting loads on marine structures and the general physics of ocean waves, for example.
2. Cytology specimens offer an effective alternative to formalin-fixed tissue as demonstrated by novel automated detection for ALK break-apart FISH testing and immunohistochemistry in lung adenocarcinoma.
Science.gov (United States)
Rosenblum, Frida; Hutchinson, Lloyd M; Garver, Joann; Woda, Bruce; Cosar, Ediz; Kurian, Elizabeth M
2014-11-01
Minimally invasive sampling by cytology or core needle biopsy often provides an initial diagnosis for treatment in patients with lung nodules. From these limited specimens, multiple molecular studies are frequently requested. Current guidelines from the US Food and Drug Administration recommend using formalin-fixed paraffin-embedded tissue sections for the detection of anaplastic lymphoma kinase (ALK) gene rearrangement by fluorescence in situ hybridization (FISH). The authors compared alcohol-fixed and formalin-fixed cytology specimens using a novel automated detection for ALK rearrangements by FISH and immunohistochemistry (IHC). ALK FISH testing was performed on 129 lung adenocarcinomas from 71 cytology cases and 58 biopsy/resection specimens using Papanicolaou staining with integrated cytomorphology. IHC with the ALK D5F3 antibody was performed on cases with residual material (88 of 129 cases). The mean age of the patients was 66 years; there were 62 women and 67 men. ALK gene rearrangement was present in 4% of cytology specimens (3 of 71 specimens) and 7% of surgical specimens (4 of 58 specimens). FISH in 13 cases was technically unsuccessful. Of the 7 FISH-positive cases, only 2 cytology cases (4%) and 2 surgical cases (6%) were found to be positive with the ALK antibody, demonstrating 80% concordance. The one case found to be negative for ALK by IHC demonstrated a variant rearrangement of the ALK 2p23 gene locus by FISH. The results of the current study validate the usefulness of alcohol-fixed and/or formalin-fixed cytology specimens for ALK rearrangement by a novel automated FISH method. IHC using the D5F3 antibody for ALK is specific in this limited cohort. The authors also demonstrated that alcohol-fixed cytology specimens can be used for ALK rearrangement by automated FISH, alone or in conjunction with IHC. © 2014 American Cancer Society.
3. Attitude Strength.
Science.gov (United States)
Howe, Lauren C; Krosnick, Jon A
2017-01-03
Attitude strength has been the focus of a huge volume of research in psychology and related sciences for decades. The insights offered by this literature have tremendous value for understanding attitude functioning and structure and for the effective application of the attitude concept in applied settings. This is the first Annual Review of Psychology article on the topic, and it offers a review of theory and evidence regarding one of the most researched strength-related attitude features: attitude importance. Personal importance is attached to an attitude when the attitude is perceived to be relevant to self-interest, social identification with reference groups or reference individuals, and values. Attaching personal importance to an attitude causes crystallizing of attitudes (via enhanced resistance to change), effortful gathering and processing of relevant information, accumulation of a large store of well-organized relevant information in long-term memory, enhanced attitude extremity and accessibility, enhanced attitude impact on the regulation of interpersonal attraction, energizing of emotional reactions, and enhanced impact of attitudes on behavioral intentions and action. Thus, important attitudes are real and consequential psychological forces, and their study offers opportunities for addressing behavioral change.
4. Supersymmetry breaking with extra dimensions
International Nuclear Information System (INIS)
Zwirner, Fabio
2004-01-01
This talk reviews some aspects of supersymmetry breaking in the presence of extra dimensions. The first part is a general introduction, recalling the motivations for supersymmetry and extra dimensions, as well as some unsolved problems of four-dimensional models of supersymmetry breaking. The central part is a more focused introduction to a mechanism for (super)symmetry breaking, proposed first by Scherk and Schwarz, where extra dimensions play a crucial role. The last part is devoted to the description of some recent results and of some open problems. (author)
5. Stochastic mechanism of symmetry breaking
International Nuclear Information System (INIS)
Baseyan, H.Z.
1983-01-01
A new symmetry breaking mechanism conditioned by presence of random fields in vacuum is proposed. Massive Yang-Mills fields finally arise, that may be interpreted as ''macroscopic'' manifestation of the ''microscopic'' Yang-Mills massless theory
6. Spontaneous Lorentz breaking at high energies
International Nuclear Information System (INIS)
Cheng, H.-C.; Luty, Markus A.; Mukohyama, Shinji; Thaler, Jesse
2006-01-01
Theories that spontaneously break Lorentz invariance also violate diffeomorphism symmetries, implying the existence of extra degrees of freedom and modifications of gravity. In the minimal model ('ghost condensation') with only a single extra degree of freedom at low energies, the scale of Lorentz violation cannot be larger than about M ∼ 100GeV due to an infrared instability in the gravity sector. We show that Lorentz symmetry can be broken at much higher scales in a non-minimal theory with additional degrees of freedom, in particular if Lorentz symmetry is broken by the vacuum expectation value of a vector field. This theory can be constructed by gauging ghost condensation, giving a systematic effective field theory description that allows us to estimate the size of all physical effects. We show that nonlinear effects become important for gravitational fields with strength Φ 1/2 ∼> g, where g is the gauge coupling, and we argue that the nonlinear dynamics is free from singularities. We then analyze the phenomenology of the model, including nonlinear dynamics and velocity-dependent effects. The strongest bounds on the gravitational sector come from either black hole accretion or direction-dependent gravitational forces, and imply that the scale of spontaneous Lorentz breaking is M ∼ 12 GeV, g 2 10 15 GeV). If the Lorentz breaking sector couples directly to matter, there is a spin-dependent inverse-square law force, which has a different angular dependence from the force mediated by the ghost condensate, providing a distinctive signature for this class of models
7. Strength and lifetime of polymer glasses
Energy Technology Data Exchange (ETDEWEB)
Bartenev, G.M.; Kartasov, E.M.
1981-03-01
A kinetic equation of the time-dependence of strength (complete isotherm of lifetime) of polymer glasses at stress values ranging from the limiting stress of the occurence of separation breaks to the critical stress is derived. The curvature of lifetime plots occuring at low and high periods of time in the experiments are considered. The ranges of noncritical state, breaks caused by a thermofluctuation mechanism, a transition range and athermal breaks are discerned. The limitations of applicability of the basic empirical equation of the kinetic theory of the time-dependence of strength are explained. Theoretical equations are suggested for calculating various characteristics of the brittle break, as limiting stress and critical stress, relative critical craze length and coefficient of stress concentration at the craze tip with respect to various geometrical configurations of the craze and its position in the sample. With polymethylmethacrylate as an example in the brittle and quasi-brittle state, as characterized by the transition from the rupture of sets of chemical bonds to individual chemical bonds, the thermofluctuation processes of break in polymer glasses are discussed. The application of the thermofluctuation theory of solids to the quasi-brittle fracture is considered. The growth kinetics of crazes and the corresponding equation of lifetime were found to be described by identical (corresponding) analytical expressions by which the changes of the coefficients of stress concentration in the range of microplastic deformation in front of the growing is covered within a wide region of temperature including the brittle temperature.
8. Mechanical enhancement and in vitro biocompatibility of nanofibrous collagen-chitosan scaffolds for tissue engineering.
Science.gov (United States)
Zou, Fengjuan; Li, Runrun; Jiang, Jianjun; Mo, Xiumei; Gu, Guofeng; Guo, Zhongwu; Chen, Zonggang
2017-12-01
The collagen-chitosan complex with a three-dimensional nanofiber structure was fabricated to mimic native ECM for tissue repair and biomedical applications. Though the three-dimensional hierarchical fibrous structures of collagen-chitosan composites could provide more adequate stimulus to facilitate cell adhesion, migrate and proliferation, and thus have the potential as tissue engineering scaffolding, there are still limitations in their applications due to the insufficient mechanical properties of natural materials. Because poly (vinyl alcohol) (PVA) and thermoplastic polyurethane (TPU) as biocompatible synthetic polymers can offer excellent mechanical properties, they were introduced into the collagen-chitosan composites to fabricate the mixed collagen/chitosan/PVA fibers and a sandwich structure (collagen/chitosan-TPU-collagen/chitosan) of nanofiber in order to enhance the mechanical properties of the nanofibrous collagen-chitosan scaffold. The results showed that the tensile behavior of materials was enhanced to different degrees with the difference of collagen content in the fibers. Besides the Young's modulus had no obvious changes, both the break strength and the break elongation of materials were heightened after reinforced by PVA. For the collagen-chitosan nanofiber reinforced by TPU, both the break strength and the Young's modulus of materials were heightened in different degrees with the variety of collagen content in the fibers despite the decrease of the break elongation of materials to some extent. In vitro cell test demonstrated that the materials could provide adequate environment for cell adhesion and proliferation. All these indicated that the reinforced collagen-chitosan nanofiber could be as potential scaffold for tissue engineering according to the different mechanical requirements in clinic.
9. Breaking diffeomorphism invariance and tests for the emergence of gravity
International Nuclear Information System (INIS)
Anber, Mohamed M.; Aydemir, Ufuk; Donoghue, John F.
2010-01-01
If general relativity is an emergent phenomenon, there may be small violations of diffeomorphism invariance. We propose a phenomenology of perturbatively small violations of general relativity by the inclusion of terms which break general covariance. These can be tested by matching to the parameterized post-Newtonian formalism. The most sensitive tests involve pulsar timing and provide an extremely strong bound, with a dimensionless constraint of order 10 -20 relative to gravitational strength.
10. Bond strength of masonry
NARCIS (Netherlands)
Pluijm, van der R.; Vermeltfoort, A.Th.
1992-01-01
Bond strength is not a well defined property of masonry. Normally three types of bond strength can be distinguished: - tensile bond strength, - shear (and torsional) bond strength, - flexural bond strength. In this contribution the behaviour and strength of masonry in deformation controlled uniaxial
11. String breaking with Wilson loops?
CERN Document Server
Kratochvila, S; Kratochvila, Slavo; Forcrand, Philippe de
2003-01-01
A convincing, uncontroversial observation of string breaking, when the static potential is extracted from Wilson loops only, is still missing. This failure can be understood if the overlap of the Wilson loop with the broken string is exponentially small. In that case, the broken string ground state will only be seen if the Wilson loop is long enough. Our preliminary results show string breaking in the context of the 3d SU(2) adjoint static potential, using the L\\"uscher-Weisz exponential variance reduction approach. As a by-product, we measure the fundamental SU(2) static potential with improved accuracy and see clear deviations from Casimir scaling.
12. Code breaking in the pacific
CERN Document Server
Donovan, Peter
2014-01-01
Covers the historical context and the evolution of the technically complex Allied Signals Intelligence (Sigint) activity against Japan from 1920 to 1945 Describes, explains and analyzes the code breaking techniques developed during the war in the Pacific Exposes the blunders (in code construction and use) made by the Japanese Navy that led to significant US Naval victories
13. Strong coupling electroweak symmetry breaking
International Nuclear Information System (INIS)
Barklow, T.L.; Burdman, G.; Chivukula, R.S.
1997-04-01
The authors review models of electroweak symmetry breaking due to new strong interactions at the TeV energy scale and discuss the prospects for their experimental tests. They emphasize the direct observation of the new interactions through high-energy scattering of vector bosons. They also discuss indirect probes of the new interactions and exotic particles predicted by specific theoretical models
14. Appointment breaking: causes and solutions.
Science.gov (United States)
Bean, A G; Talaga, J
1992-12-01
From a review of research on health care appointment breaking, the authors find that patient demographic characteristics, psychosocial problems, previous appointment keeping, health beliefs, and situational factors predict no-show behavior. Suggestions are offered for designing the marketing mix to increase patient appointment keeping. Methods for mitigating the negative effects of no-shows on health care providers are described.
15. Strong coupling electroweak symmetry breaking
Energy Technology Data Exchange (ETDEWEB)
Barklow, T.L. [Stanford Linear Accelerator Center, Menlo Park, CA (United States); Burdman, G. [Univ. of Wisconsin, Madison, WI (United States). Dept. of Physics; Chivukula, R.S. [Boston Univ., MA (United States). Dept. of Physics
1997-04-01
The authors review models of electroweak symmetry breaking due to new strong interactions at the TeV energy scale and discuss the prospects for their experimental tests. They emphasize the direct observation of the new interactions through high-energy scattering of vector bosons. They also discuss indirect probes of the new interactions and exotic particles predicted by specific theoretical models.
16. Oil prices: Breaks and trends
International Nuclear Information System (INIS)
Noguera, José
2013-01-01
This paper contributes to the literature of the stationarity of financial time series and the literature on oil and macroeconomics in several ways. First, it uses Kejriwal and Perron (2010) sequential procedure to endogenously determine multiple structural changes in real oil prices without facing the circular testing problem between structural changes and stationary assumptions of previous tests. Second, it performs a diagnostic check to detect the significance and magnitude of the potential breaks. Third, it uses the above information to test for the existence of stochastic trends in real oil prices, and fourth, it speculates about possible explanations for the break dates found in order to encourage further work and discussions. The exercise uses monthly data from January 1861 to August 2011. - Highlights: ► The model endogenously determine multiple structural changes in real oil prices. ► The methods used does not face the circular testing problem. ► It also detect the significance and magnitude of the breaks detected. ► It tests for the existence of stochastic trends. ► It explains the reasons for the break dates found
17. Instantons and chiral symmetry breaking
International Nuclear Information System (INIS)
Carneiro, C.E.I.; McDougall, N.A.
1984-01-01
A detailed investigation of chiral symmetry breaking due to instanton dynamics is carried out, within the framework of the dilute gas approximation, for quarks in both the fundamental and adjoint representations of SU(2). The momentum dependence of the dynamical mass is found to be very similar in each representation. (orig.)
18. Instantons and chiral symmetry breaking
Energy Technology Data Exchange (ETDEWEB)
Carneiro, C.E.I.; McDougall, N.A. (Oxford Univ. (UK). Dept. of Theoretical Physics)
1984-10-22
A detailed investigation of chiral symmetry breaking due to instanton dynamics is carried out, within the framework of the dilute gas approximation, for quarks in both the fundamental and adjoint representations of SU(2). The momentum dependence of the dynamical mass is found to be very similar in each representation.
19. Inflationary implications of supersymmetry breaking
NARCIS (Netherlands)
Borghese, Andrea; Roest, Diederik; Zavala, Ivonne
2013-01-01
We discuss a general bound on the possibility to realise inflation in any minimal supergravity with F-terms. The derivation crucially depends on the sGoldstini, the scalar field directions that are singled out by spontaneous supersymmetry breaking. The resulting bound involves both slow-roll
20. Aluminum break-point contacts
NARCIS (Netherlands)
Heinemann, Martina; Groot, R.A. de
1997-01-01
Ab initio molecular dynamics is used to study the contribution of a single Al atom to an aluminum breakpoint contact during the final stages of breaking and the initial stages of the formation of such a contact. A hysteresis effect is found in excellent agreement with experiment and the form of the
1. Breaking Carbon Lock-in
DEFF Research Database (Denmark)
Driscoll, Patrick Arthur
2014-01-01
This central focus of this paper is to highlight the ways in which path dependencies and increasing returns (network effects) serve to reinforce carbon lock-in in large-scale road transportation infrastructure projects. Breaking carbon lock-in requires drastic changes in the way we plan future...
2. Parental Break-Ups and Stress
DEFF Research Database (Denmark)
Dissing, Agnete S.; Dich, Nadya; Nybo Andersen, Anne-Marie
2017-01-01
Background: Parental break-up is wide spread, and the effects of parental break-up on children’s well-being are known. The evidence regarding child age at break-up and subsequent family arrangements is inconclusive. Aim: to estimate the effects of parental break-up on stress in pre-adolescent chi......Background: Parental break-up is wide spread, and the effects of parental break-up on children’s well-being are known. The evidence regarding child age at break-up and subsequent family arrangements is inconclusive. Aim: to estimate the effects of parental break-up on stress in pre......-adolescent children with a specific focus on age at break-up and post-breakup family arrangements. Methods: We used data from the Danish National Birth Cohort. Participants included 44 509 children followed from birth to age 11. Stress was self-reported by children at age 11, when the children also reported...... on parental break-up and post break-up family arrangements. Results: Twenty-one percent of the children had experienced a parental break-up at age 11, and those who had experienced parental break-up showed a higher risk of stress (OR:1.72, 95%CI:1.55;1.91) regardless of the child’s age at break-up. Children...
3. Stress corrosion evaluation of powder metallurgy aluminum alloy 7091 with the breaking load test method
Science.gov (United States)
Domack, Marcia S.
1987-01-01
The stress corrosion behavior of the P/M aluminum alloy 7091 is evaluated in two overaged heat treatment conditions, T7E69 and T7E70, using an accelerated test technique known as the breaking load test method. The breaking load data obtained in this study indicate that P/M 7091 alloy is highly resistant to stress corrosion in both longitudinal and transverse orientations at stress levels up to 90 percent of the material yield strength. The reduction in mean breaking stress as a result of corrosive attack is smallest for the more overaged T7E70 condition. Details of the test procedure are included.
4. Improving long term driving comfort by taking breaks - how break activity affects effectiveness
OpenAIRE
Sammonds, GM; Mansfield, NJ; Fray, M
2017-01-01
During long duration journeys, drivers are encouraged to take regular breaks. The benefits of breaks have been documented for safety; breaks may also be beneficial for comfort. The activity undertaken during a break may influence its effectiveness. Volunteers completed 3 journeys on a driving simulator. Each 130 min journey included a 10 min break after the first hour. During the break volunteers either stayed seated, left the simulator and sat in an adjacent room, or took a walk on a treadmi...
5. A model of intrinsic symmetry breaking
International Nuclear Information System (INIS)
Ge, Li; Li, Sheng; George, Thomas F.; Sun, Xin
2013-01-01
Different from the symmetry breaking associated with a phase transition, which occurs when the controlling parameter is manipulated across a critical point, the symmetry breaking presented in this Letter does not need parameter manipulation. Instead, the system itself suddenly undergoes symmetry breaking at a certain time during its evolution, which is intrinsic symmetry breaking. Through a polymer model, it is revealed that the origin of the intrinsic symmetry breaking is nonlinearity, which produces instability at the instance when the evolution crosses an inflexion point, where this instability breaks the original symmetry
6. Targeting abnormal DNA double strand break repair in cancer
OpenAIRE
Rassool, Feyruz V.; Tomkinson, Alan E.
2010-01-01
A major challenge in cancer treatment is the development of therapies that target cancer cells with little or no toxicity to normal tissues and cells. Alterations in DNA double strand break (DSB) repair in cancer cells include both elevated and reduced levels of key repair proteins and changes in the relative contributions of the various DSB repair pathways. These differences can result in increased sensitivity to DSB-inducing agents and increased genomic instability. The development of agent...
7. Physics of chiral symmetry breaking
International Nuclear Information System (INIS)
Shuryak, E.V.
1991-01-01
This subsection of the 'Modeling QCD' Workshop has included five talks. E. Shuryak spoke on 'Recent Progress in Understanding Chiral Symmetry Breaking'; below it is split into two parts: (i) a mini-review of the field and (ii) a brief presentation of the status of the theory of interacting instantons. The next sections correspond to the following talks: (iii) K. Goeke et al., 'Chiral Restoration and Medium Corrections to Nucleon in the NJL Model'; (iv) M. Takizawa and K. Kubodera, 'Study of Meson Properties and Quark Condensates in the NJL Model with Instanton Effects'; (v) G. Klein and A. G. Williams, 'Dynamical Chiral Symmetry Breaking in Dual QCD'; and (vi) R. D. Ball, 'Skyrmions and Baryons.' (orig.)
8. Supersymmetry breaking by gaugino condensation
International Nuclear Information System (INIS)
Casas, J.A.
1991-01-01
We briefly review the status and some of the recent work on supersymmetry breaking by gaugino condensation effects in the context of superstring theories. This issue is intimately related to the structure of the effective potential coming from superstrings. Minimization of this not only allows to find the scale of supersymmetry breaking, but also to determine dynamically other fundamental parameters of the theory, in particular the gauge coupling constant at the unification point and the expectation values of the moduli which give the size and shape of the compactified space. In a multiple condensate scenario these get reasonable values which may, in turn, lead to a determination of the family mass hierarchy. Some directions for future work are examined too. (author). 23 refs
9. Post accidental small breaks analysis
International Nuclear Information System (INIS)
Depond, G.; Gandrille, J.
1980-04-01
EDF ordered to FRAMATOME by 1977 to complete post accidental long term studies on 'First Contrat-Programme' reactors, in order to demonstrate the safety criteria long term compliance, to get information on NSSS behaviour and to improve the post accidental procedures. Convenient analytical models were needed and EDF and FRAMATOME respectively developped the AXEL and FRARELAP codes. The main results of these studies is that for the smallest breaks, it is possible to manually undertake cooling and pressure reducing actions by dumping the steam generators secondary side in order to meet the RHR operating specifications and perform long term cooling through this system. A specific small breaks procedure was written on this basis. The EDF and FRAMATOME codes are continuously improved; the results of a French set of separate effects experiments will be incorporated as well as integral system verification
10. Prophylactic treatment of retinal breaks
DEFF Research Database (Denmark)
Blindbæk, Søren Leer; Grauslund, Jakob
2015-01-01
Prophylactic treatment of retinal breaks has been examined in several studies and reviews, but so far, no studies have successfully applied a systematic approach. In the present systematic review, we examined the need of follow-up after posterior vitreous detachment (PVD) - diagnosed by slit...... published before 2012. Four levels of screening identified 13 studies suitable for inclusion in this systematic review. No meta-analysis was conducted as no data suitable for statistical analysis were identified. In total, the initial examination after symptomatic PVD identified 85-95% of subsequent retinal......-47% of cases, respectively. The cumulated incidence of RRD despite prophylactic treatment was 2.1-8.8%. The findings in this review suggest that follow-up after symptomatic PVD is only necessary in cases of incomplete retinal examination at presentation. Prophylactic treatment of symptomatic retinal breaks...
11. Breaking through the tranfer tunnel
CERN Document Server
Laurent Guiraud
2001-01-01
This image shows the tunnel boring machine breaking through the transfer tunnel into the LHC tunnel. Proton beams will be transferred from the SPS pre-accelerator to the LHC at 450 GeV through two specially constructed transfer tunnels. From left to right: LHC Project Director, Lyn Evans; CERN Director-General (at the time), Luciano Maiani, and Director for Accelerators, Kurt Hubner.
12. Models of electroweak symmetry breaking
CERN Document Server
Pomarol, Alex
2015-01-01
This chapter present models of electroweak symmetry breaking arising from strongly interacting sectors, including both Higgsless models and mechanisms involving a composite Higgs. These scenarios have also been investigated in the framework of five-dimensional warped models that, according to the AdS/CFT correspondence, have a four-dimensional holographic interpretation in terms of strongly coupled field theories. We explore the implications of these models at the LHC.
13. Supersymmetry breaking at finite temperature
International Nuclear Information System (INIS)
Kratzert, K.
2002-11-01
The mechanism of supersymmetry breaking at finite temperature is still only partly understood. Though it has been proven that temperature always breaks supersymmetry, the spontaneous nature of this breaking remains unclear, in particular the role of the Goldstone fermion. The aim of this work is to unify two existing approaches to the subject. From a hydrodynamic point of view, it has been argued under very general assumptions that in any supersymmetric quantum field theory at finite temperature there should exist a massless fermionic collective excitation, named phonino because of the analogy to the phonon. In the framework of a self-consistent resummed perturbation theory, it is shown for the example of the Wess-Zumino model that this mode fits very well into the quantum field theoretical framework pursued by earlier works. Interpreted as a bound state of boson and fermion, it contributes to the supersymmetric Ward-Takahashi identities in a way showing that supersymmetry is indeed broken spontaneously with the phonino playing the role of the Goldstone fermion. The second part of the work addresses the case of supersymmetric quantum electrodynamics. It is shown that also here the phonino exists and must be interpreted as the Goldstone mode. This knowledge allows a generalization to a wider class of models. (orig.)
14. Defining Nitrogen Kinetics for Air Break in Prebreathe
Science.gov (United States)
Conkin, Johnny
2009-01-01
Actual tissue nitrogen (N2) kinetics are complex; the uptake and elimination is often approximated with a single half-time compartment in statistical descriptions of denitrogenation [prebreathe (PB)] protocols. Air breaks during PB complicate N2 kinetics. A comparison of symmetrical versus asymmetrical N2 kinetics was performed using the time to onset of hypobaric decompression sickness (DCS) as a surrogate for actual venous N2 tension. Published results of 12 tests involving 179 hypobaric exposures in altitude chambers after PB, with and without air breaks, provide the complex protocols from which to model N2 kinetics. DCS survival time for combined control and air breaks were described with an accelerated log logistic model where N2 uptake and elimination before, during, and after the air break was computed with a simple exponential function or a function that changed half-time depending on ambient N2 partial pressure. P1N2-P2 = delta P defined DCS dose for each altitude exposure, where P2 was the test altitude and P1N2 was computed N2 pressure at the beginning of the altitude exposure. The log likelihood (LL) without DCS dose (null model) was -155.6, and improved (best-fit) to -97.2 when dose was defined with a 240 min half-time for both N2 elimination and uptake during the PB. The description of DCS survival time was less precise with asymmetrical N2 kinetics, for example, LL was -98.9 with 240 min half-time elimination and 120 min half-time uptake. The statistical regression described survival time mechanistically linked to symmetrical N2 kinetics during PBs that also included air breaks. The results are data-specific, and additional data may change the conclusion. The regression is useful to compute additional PB time to compensate for an air break in PB within the narrow range of tested conditions.
15. A simple self-breaking 2 MV gas switch
Energy Technology Data Exchange (ETDEWEB)
Di Capua, M.S.; Freytag, E.K.; Dixon, W.R.; Hawley, R.A.
1987-06-29
We describe a simple self-breaking 2 MV gas master switch for the LLNL 2 MV general purpose relativistic electron beam (REB) accelerator. The switch cavity has been hollowed out in a 17.8 cm-thick acrylic slab. The switch gap is 3.55 cm. At 2 MV the maximum field at the cathode is 740 kV cm/sup -1/ and the maximum envelope field is 172 kV cm/sup -1/. The maximum measured switching voltage is 1.90 +- 0.1 MV (10 bar abs). The minimum switching voltage is 1.1 MV (4.3 bar abs). The operating characteristics break away from the 89 kV/(cm atm) dc breakdown strength of SF/sub 6/ at 5 bar abs. Careful electrical and mechanical design as well as strict quality control during assembly and operation have resulted in reliable and reproducible operation.
16. The Strength Compass
DEFF Research Database (Denmark)
Ledertoug, Mette Marie
In the Ph.D-project ͚Strengths-based Learning - Children͛s character strengths as a means to their learning potential͛ 750 Danish children have assessed ͚The Strength Compass͛ in order to identify their strengths and to create awareness of strengths. This was followed by a strengths......-based intervention program in order to explore the strengths. Finally different methods to apply the strength in everyday life at school were applied. The paper presentation will show the results for strengths display for children aged 6-16 in different categories: Different age groups: Are the same strengths...... present in both small children and youths? Gender: Do the results show differences between the two genders? Danish as a mother- tongue language: Do the results show any differences in the strengths display when considering different language and cultural backgrounds? Children with Special Needs: Do...
17. Electroweak symmetry breaking: Higgs/whatever
International Nuclear Information System (INIS)
Chanowitz, M.S.
1990-01-01
In these two lectures the author discusses electroweak symmetry breaking from a general perspective, stressing properties that are model independent and follow just from the assumption that the electroweak interactions are described by a spontaneously broken gauge theory. This means he assumes the Higgs mechanism though not necessarily the existence of Higgs bosons. The first lecture presents the general framework of a spontaneously broken gauge theory: (1) the Higgs mechanism sui generis, with or without Higgs boson(s) and (2) the implications of symmetry and unitarity for the mass scale and interaction strength of the new physics that the Higgs mechanism requires. In addition he reviews a softer theoretical argument based on the naturalness problem which leads to a prejudice against Higgs bosons unless they are supersymmetric. This is a prejudice, not a theorem, and it could be overturned in the future by a clever new idea. In the second lecture he illustrates the general framework by reviewing some specific models: (1) the Weinberg-Salam model of the Higgs sector; (2) the minimal supersymmetric extension of the Weinberg-Salam model; and (3) technicolor as an example of the Higgs mechanism without Higgs bosons. He concludes the second lecture with a discussion of strong WW scattering that must occur if L SB lives above 1 TeV. In particular he describes some of the experimental signals and backgrounds at the SSC. 57 refs., 12 figs
18. The Character Strengths of Class Clowns
Directory of Open Access Journals (Sweden)
Willibald F. Ruch
2014-09-01
Full Text Available Class clowns traditionally were studied as a type concept and identified via sociometric procedures. In the present study a variable-centered approach was favored and class clown behaviors were studied in the context of character strengths, orientations to happiness and satisfaction with life. A sample of 672 Swiss children and adolescents filled in an 18 item self-report instrument depicting class clown behaviors. A hierarchical model of class clown behaviors was developed distinguishing a general factor and the four positively correlated dimensions of identified as a class clown, comic talent, disruptive rule-breaker, and subversive joker. Analysis of the general factor showed that class clowns were primarily male, and tended to be seen as class clowns by the teacher. Analyses of the 24 character strengths of the VIA-Youth (Park & Peterson, 2006 showed that class clowns were high in humor and leadership, and low in strengths like prudence, self-regulation, modesty, honesty, fairness, perseverance, and love of learning. An inspection of signature strengths revealed that 75% of class clowns had humor as a signature strength. Furthermore, generally class clown behaviors were shown by students indulging in a life of pleasure, but low life of engagement. The four dimensions yielded different character strengths profiles. While all dimensions of class clowns behaviors were low in temperance strengths, the factors identified as the class clown and comic talent were correlated with leadership strengths and the two negative factors (disruptive rule-breaker, subversive joker were low in other directed strengths. The disruptive rule breaking class clown was additionally low in intellectual strengths. While humor predicted life satisfaction, class clowning tended to go along with diminished satisfaction with life. It is concluded that different types of class clowns need to be kept apart and need different attention by teachers.
19. The character strengths of class clowns.
Science.gov (United States)
Ruch, Willibald; Platt, Tracey; Hofmann, Jennifer
2014-01-01
Class clowns traditionally were studied as a type concept and identified via sociometric procedures. In the present study a variable-centered approach was favored and class clown behaviors were studied in the context of character strengths, orientations to happiness and satisfaction with life. A sample of 672 Swiss children and adolescents filled in an 18 item self-report instrument depicting class clown behaviors. A hierarchical model of class clown behaviors was developed distinguishing a general factor and the four positively correlated dimensions of "identified as a class clown," "comic talent," "disruptive rule-breaker," and "subversive joker." Analysis of the general factor showed that class clowns were primarily male, and tended to be seen as class clowns by the teacher. Analyses of the 24 character strengths of the VIA-Youth (Park and Peterson, 2006) showed that class clowns were high in humor and leadership, and low in strengths like prudence, self-regulation, modesty, honesty, fairness, perseverance, and love of learning. An inspection of signature strengths revealed that 75% of class clowns had humor as a signature strength. Furthermore, class clown behaviors were generally shown by students indulging in a life of pleasure, but low life of engagement. The four dimensions yielded different character strengths profiles. While all dimensions of class clowns behaviors were low in temperance strengths, the factors "identified as the class clown" and "comic talent" were correlated with leadership strengths and the two negative factors ("disruptive rule-breaker," "subversive joker") were low in other directed strengths. The disruptive rule breaking class clown was additionally low in intellectual strengths. While humor predicted life satisfaction, class clowning tended to go along with diminished satisfaction with life. It is concluded that different types of class clowns need to be kept apart and need different attention by teachers.
20. Leaders break ground for INFINITY
Science.gov (United States)
2008-01-01
Community leaders from Mississippi and Louisiana break ground for the new INFINITY at NASA Stennis Space Center facility during a Nov. 20 ceremony. Groundbreaking participants included (l to r): Gottfried Construction representative John Smith, Mississippi Highway Commissioner Wayne Brown, INFINITY board member and Apollo 13 astronaut Fred Haise, Stennis Director Gene Goldman, Studio South representative David Hardy, Leo Seal Jr. family representative Virginia Wagner, Hancock Bank President George Schloegel, Mississippi Rep. J.P. Compretta, Mississippi Band of Choctaw Indians representative Charlie Benn and Louisiana Sen. A.G. Crowe.
1. Give Young Scientists a Break
Energy Technology Data Exchange (ETDEWEB)
Wiley, H. S.
2009-11-01
There has been much concern about the impact of tight funding on the careers of young scientists. When only a small percentage of grants are approved, even the smallest problem or error with an application can push it out of the funding range. Unfortunately, the relative lack of grant writing skills by new investigators often has this effect. To avoid a situation where only experienced investigators with polished writing skills are funded, the National Institutes of Health has instituted a more generous ranking scale for new investigators. Not surprisingly, some senior investigators have protested, calling it reverse discrimination. I say that their anger is misplaced. New investigators do deserve a break.
2. Inflationary implications of supersymmetry breaking
Energy Technology Data Exchange (ETDEWEB)
Borghese, Andrea; Roest, Diederik; Zavala, Ivonne [Centre for Theoretical Physics, University of Groningen, Nijenborgh 4, 9747 AG Groningen (Netherlands)
2013-07-23
We discuss a general bound on the possibility to realise inflation in any minimal supergravity with F-terms. The derivation crucially depends on the sGoldstini, the scalar field directions that are singled out by spontaneous supersymmetry breaking. The resulting bound involves both slow-roll parameters and the geometry of the Kähler manifold of the chiral scalars. We analyse the inflationary implications of this bound, and in particular discuss to what extent the requirements of single field and slow-roll can both be met in F-term inflation.
3. History of electroweak symmetry breaking
International Nuclear Information System (INIS)
Kibble, T W B
2015-01-01
In this talk, I recall the history of the development of the unified electroweak theory, incorporating the symmetry-breaking Higgs mechanism, as I saw it from my standpoint as a member of Abdus Salam's group at Imperial College. I start by describing the state of physics in the years after the Second World War, explain how the goal of a unified gauge theory of weak and electromagnetic interactions emerged, the obstacles encountered, in particular the Goldstone theorem, and how they were overcome, followed by a brief account of more recent history, culminating in the historic discovery of the Higgs boson in 2012. (paper)
4. Sediment transport under breaking waves
DEFF Research Database (Denmark)
Christensen, Erik Damgaard; Hjelmager Jensen, Jacob; Mayer, Stefan
2000-01-01
The sediment transport in the surf zone is modelled by combining a Navier-Stokes solver, a free surface model, a turbulence model, and a sediment transport model. The flow solver is based on the finite volume technique for non-orthogonal grids. The model is capable of simulating the turbulence...... generated at the surface where the wave breaks as well as the turbulence generated near the bed due to the wave-motion and the undertow. In general, the levels of turbulent kinetic energy are found to be higher than experiments show. This results in an over prediction of the sediment transport. Nevertheless...
5. Forecasting long memory time series under a break in persistence
DEFF Research Database (Denmark)
Heinen, Florian; Sibbertsen, Philipp; Kruse, Robinson
We consider the problem of forecasting time series with long memory when the memory parameter is subject to a structural break. By means of a large-scale Monte Carlo study we show that ignoring such a change in persistence leads to substantially reduced forecasting precision. The strength...... of this effect depends on whether the memory parameter is increasing or decreasing over time. A comparison of six forecasting strategies allows us to conclude that pre-testing for a change in persistence is highly recommendable in our setting. In addition we provide an empirical example which underlines...
6. Investigation on the effect of atomic defects on the breaking behaviors of gold nanowires
International Nuclear Information System (INIS)
Wang Fenying; Sun Wei; Wang Hongbo; Zhao Jianwei; Kiguchi, Manabu; Sun Changqing
2012-01-01
The mechanical properties and breaking behaviors of the [100]-oriented single-crystal gold nanowires containing a set of defect ratios have been studied at different temperatures using molecular dynamics simulations. The size of the nanowire is 10a × 10a × 30a (a stands for lattice constant, 0.408 nm for gold). The mechanical strengths of the nanowires decrease with the increasing temperature. However, the defects that enhance the local thermal energy have improved the nanowire mechanical strength under a wide range of temperature. Comparing to the single-crystal nanowire, the existence of the atomic defects extends the elastic deformation showing a larger yield strain. By summarizing 300 samples at each temperature, the statistical breaking position distribution shows that the nanowire breaking behavior is sensitive to the atomic defects when the defect ratio is 5 % at 100 K, whereas the ratio is 1 % when temperatures are 300 and 500 K.
7. THE MAKE BREAK TEST AS A DIAGNOSTIC-TOOL IN FUNCTIONAL WEAKNESS
NARCIS (Netherlands)
VANDERPLOEG, RJO; OOSTERHUIS, HJGH
Strength was measured in four major muscle groups with a hand-held dynamometer. The "make" and "break" technique was used with and without encouragement, and fatiguability was tested in patients with organic weakness and patients with functional weakness. Patients with functional weakness could be
8. Structural Break Tests Robust to Regression Misspecification
Directory of Open Access Journals (Sweden)
Alaa Abi Morshed
2018-05-01
Full Text Available Structural break tests for regression models are sensitive to model misspecification. We show—analytically and through simulations—that the sup Wald test for breaks in the conditional mean and variance of a time series process exhibits severe size distortions when the conditional mean dynamics are misspecified. We also show that the sup Wald test for breaks in the unconditional mean and variance does not have the same size distortions, yet benefits from similar power to its conditional counterpart in correctly specified models. Hence, we propose using it as an alternative and complementary test for breaks. We apply the unconditional and conditional mean and variance tests to three US series: unemployment, industrial production growth and interest rates. Both the unconditional and the conditional mean tests detect a break in the mean of interest rates. However, for the other two series, the unconditional mean test does not detect a break, while the conditional mean tests based on dynamic regression models occasionally detect a break, with the implied break-point estimator varying across different dynamic specifications. For all series, the unconditional variance does not detect a break while most tests for the conditional variance do detect a break which also varies across specifications.
9. The strength compass
DEFF Research Database (Denmark)
Ledertoug, Mette Marie
of agreement/disagreement. Also the child/teacher is asked whether the actual strength is important and if he or she has the possibilities to apply the strength in the school. In a PhDproject ‘Strengths-based Learning - Children’s Character Strengths as Means to their Learning Potential’ 750 Danish children......Individual paper presentation: The ‘Strength Compass’. The results of a PhDresearch project among schoolchildren (age 6-16) identifying VIAstrengths concerning age, gender, mother-tongue-langue and possible child psychiatric diagnosis. Strengths-based interventions in schools have a theoretical...... Psychological Publishing Company. ‘The Strength Compass’ is a computer/Ipad based qualitative tool to identify the strengths of a child by a self-survey or a teacher’s survey. It is designed as a visual analogue scale with a statement of the strength in which the child/teacher may declare the degree...
10. Toughening elastomers with sacrificial bonds and watching them break
Science.gov (United States)
Creton, Costantino
2014-03-01
Most unfilled elastomers are relatively brittle, in particular when the average molecular weight between crosslinks is lower than the average molecular weight between entanglements. We created a new class of tough elastomers by introducing isotropically prestretched chains inside ordinary acrylic elastomers by successive swelling and polymerization steps. These new materials combine a high entanglement density with a densely crosslinked structure reaching elastic moduli of 4 MPa and fracture strength of 25 MPa. The highly prestretched chains are the minority in the material and can break in the bulk of the material before catastrophic failure occurs, increasing the toughness of the material by two orders of magnitude up to 5 kJ/m2. To investigate the details of the toughening mechanism we introduced specific sacrificial dioxetane bonds in the prestretched chains that emit light when they break. In uniaxial extension cyclic experiments, we checked that the light emission corresponded exactly and quantitatively to the energy dissipation in each cycle demonstrating that short chains break first and long chains later. We then watched crack propagation in notched samples and mapped spatially the location of bond breakage ahead of the crack tip before and during propagation. This new toughening mechanism for elastomers creates superentangled rubbers and is ideally suited to overcome the trade-off between toughness and stiffness of ordinary elastomers. We gratefully acknowledge funding from DSM Ahead
11. Symmetry breaking in gauge glasses
International Nuclear Information System (INIS)
Hansen, K.
1988-09-01
In order to explain why nature selects the gauge groups of the Standard Model, Brene and Nielsen have proposed a way to break gauge symmetry which does not rely on the existence of a Higgs field. The observed gauge groups will in this scheme appear as the only surviving ones when this mechanism is applied to a random selection of gauge groups. The essential assumption is a discrete space-time with random couplings. Some working assumptions were made for computational reasons of which the most important is that quantum fluctuations were neclected. This work presents an example which under the same conditions show that a much wider class of groups than predicted by Brene and Nielsen will be broken. In particular no possible Standard Model Group survives unbroken. Numerical calculations support the analytical result. (orig.)
12. Rotational Symmetry Breaking in Baby Skyrme Models
Science.gov (United States)
Karliner, Marek; Hen, Itay
We discuss one of the most interesting phenomena exhibited by baby skyrmions - breaking of rotational symmetry. The topics we will deal with here include the appearance of rotational symmetry breaking in the static solutions of baby Skyrme models, both in flat as well as in curved spaces, the zero-temperature crystalline structure of baby skyrmions, and finally, the appearance of spontaneous breaking of rotational symmetry in rotating baby skyrmions.
13. Big break for charge symmetry
Energy Technology Data Exchange (ETDEWEB)
Miller, G.A. [Department of Physics, University of Washington, Seattle (United States); Kolck, U. van [Department of Physics, University of Arizona, Tucson (United States)
2003-06-01
Two new experiments have detected charge-symmetry breaking, the mechanism responsible for protons and neutrons having different masses. Symmetry is a crucial concept in the theories that describe the subatomic world because it has an intimate connection with the laws of conservation. The theory of the strong interaction between quarks - quantum chromodynamics - is approximately invariant under what is called charge symmetry. In other words, if we swap an up quark for a down quark, then the strong interaction will look almost the same. This symmetry is related to the concept of {sup i}sospin{sup ,} and is not the same as charge conjugation (in which a particle is replaced by its antiparticle). Charge symmetry is broken by the competition between two different effects. The first is the small difference in mass between up and down quarks, which is about 200 times less than the mass of the proton. The second is their different electric charges. The up quark has a charge of +2/3 in units of the proton charge, while the down quark has a negative charge of -1/3. If charge symmetry was exact, the proton and the neutron would have the same mass and they would both be electrically neutral. This is because the proton is made of two up quarks and a down quark, while the neutron comprises two downs and an up. Replacing up quarks with down quarks, and vice versa, therefore transforms a proton into a neutron. Charge-symmetry breaking causes the neutron to be about 0.1% heavier than the proton because the down quark is slightly heavier than the up quark. Physicists had already elucidated certain aspects of charge-symmetry breaking, but our spirits were raised greatly when we heard of the recent work of Allena Opper of Ohio University in the US and co-workers at the TRIUMF laboratory in British Columbia, Canada. Her team has been trying to observe a small charge-symmetry-breaking effect for several years, using neutron beams at the TRIUMF accelerator. The researchers studied the
14. Rock breaking methods to replace blasting
Science.gov (United States)
Zhou, Huisheng; Xie, Xinghua; Feng, Yuqing
2018-03-01
The method of breaking rock by blasting has a high efficiency and the cost is relatively low, but the associated vibration, flyrock, production of toxic gases since the 1970’s, the Western developed countries began to study the safety of breaking rock. This paper introduces different methods and their progress to safely break rock. Ideally, safe rock breaking would have little vibration, no fly stone, and no toxic gases, which can be widely used in municipal engineering, road excavation, high-risk mining, quarrying and complex environment.
15. NPP Krsko small break LOCA analysis
International Nuclear Information System (INIS)
Mavko, B.; Petelin, S.; Peterlin, G.
1987-01-01
Parametric analysis of small break loss of coolant accident for the Krsko NPP was calculated by using RELAP5/MOD1 computer code. The model that was used in our calculations has been improved over several years and was previously tested in simulation (s) of start-up tests and known NPP Krsko transients. In our calculations we modelled automatic actions initiated by control, safety and protection systems. We also modelled the required operator actions as specified in emergency operating instructions. In small-break LOCA calculations, we varied break sizes in the cold leg. The influence of steam generator tube plugging on small break LOCA accidents was also analysed. (author)
16. Give me a better break: Choosing workday break activities to maximize resource recovery.
Science.gov (United States)
Hunter, Emily M; Wu, Cindy
2016-02-01
Surprisingly little research investigates employee breaks at work, and even less research provides prescriptive suggestions for better workday breaks in terms of when, where, and how break activities are most beneficial. Based on the effort-recovery model and using experience sampling methodology, we examined the characteristics of employee workday breaks with 95 employees across 5 workdays. In addition, we examined resources as a mediator between break characteristics and well-being. Multilevel analysis results indicated that activities that were preferred and earlier in the work shift related to more resource recovery following the break. We also found that resources mediated the influence of preferred break activities and time of break on health symptoms and that resource recovery benefited person-level outcomes of emotional exhaustion, job satisfaction, and organizational citizenship behavior. Finally, break length interacted with the number of breaks per day such that longer breaks and frequent short breaks were associated with more resources than infrequent short breaks. (c) 2016 APA, all rights reserved).
17. Lie-algebra approach to symmetry breaking
International Nuclear Information System (INIS)
Anderson, J.T.
1981-01-01
A formal Lie-algebra approach to symmetry breaking is studied in an attempt to reduce the arbitrariness of Lagrangian (Hamiltonian) models which include several free parameters and/or ad hoc symmetry groups. From Lie algebra it is shown that the unbroken Lagrangian vacuum symmetry can be identified from a linear function of integers which are Cartan matrix elements. In broken symmetry if the breaking operators form an algebra then the breaking symmetry (or symmetries) can be identified from linear functions of integers characteristic of the breaking symmetries. The results are applied to the Dirac Hamiltonian of a sum of flavored fermions and colored bosons in the absence of dynamical symmetry breaking. In the partially reduced quadratic Hamiltonian the breaking-operator functions are shown to consist of terms of order g 2 , g, and g 0 in the color coupling constants and identified with strong (boson-boson), medium strong (boson-fermion), and fine-structure (fermion-fermion) interactions. The breaking operators include a boson helicity operator in addition to the familiar fermion helicity and ''spin-orbit'' terms. Within the broken vacuum defined by the conventional formalism, the field divergence yields a gauge which is a linear function of Cartan matrix integers and which specifies the vacuum symmetry. We find that the vacuum symmetry is chiral SU(3) x SU(3) and the axial-vector-current divergence gives a PCAC -like function of the Cartan matrix integers which reduces to PCAC for SU(2) x SU(2) breaking. For the mass spectra of the nonets J/sup P/ = 0 - ,1/2 + ,1 - the integer runs through the sequence 3,0,-1,-2, which indicates that the breaking subgroups are the simple Lie groups. Exact axial-vector-current conservation indicates a breaking sum rule which generates octet enhancement. Finally, the second-order breaking terms are obtained from the second-order spin tensor sum of the completely reduced quartic Hamiltonian
18. Strengths-based Learning
DEFF Research Database (Denmark)
Ledertoug, Mette Marie
-being. The Ph.D.-project in Strength-based learning took place in a Danish school with 750 pupils age 6-16 and a similar school was functioning as a control group. The presentation will focus on both the aware-explore-apply processes and the practical implications for the schools involved, and on measurable......Strength-based learning - Children͛s Character Strengths as Means to their Learning Potential͛ is a Ph.D.-project aiming to create a strength-based mindset in school settings and at the same time introducing strength-based interventions as specific tools to improve both learning and well...
19. Controlling break-the-glass through alignment
NARCIS (Netherlands)
Adriansyah, A.; Dongen, van B.F.; Zannone, N.
2013-01-01
Modern IT systems have to deal with unpredictable situations and exceptions more and more often. In contrast, security mechanisms are usually very rigid. Functionality like break-the-glass is thus employed to allow users to bypass security mechanisms in case of emergencies. However, break-the-glass
20. Charge-symmetry-breaking nucleon form factors
Energy Technology Data Exchange (ETDEWEB)
Kubis, Bastian, E-mail: kubis@hiskp.uni-bonn.de [Universitaet Bonn, Helmholtz-Institut fuer Strahlen- und Kernphysik (Theorie) and Bethe Center for Theoretical Physics (Germany)
2011-11-15
A quantitative understanding of charge-symmetry breaking is an increasingly important ingredient for the extraction of the nucleon's strange vector form factors. We review the theoretical understanding of the charge-symmetry-breaking form factors, both for single nucleons and for {sup 4}He.
1. Charge-symmetry-breaking nucleon form factors
International Nuclear Information System (INIS)
Kubis, Bastian
2011-01-01
A quantitative understanding of charge-symmetry breaking is an increasingly important ingredient for the extraction of the nucleon’s strange vector form factors. We review the theoretical understanding of the charge-symmetry-breaking form factors, both for single nucleons and for 4 He.
2. Breaking antidunes: Cyclic behavior due to hysteresis
DEFF Research Database (Denmark)
Deigaard, Rolf
2006-01-01
The cyclic behavior of breaking antidunes (growth, breaking of surface wave, obliteration) is investigated by use of a numerical model. The model includes the transition between supercritical and transcritical flow. As the antidune grows the flow becomes transcritical and a hydraulic jump is form...
3. Metastable Supersymmetry Breaking in a Cooling Universe
International Nuclear Information System (INIS)
2007-01-01
I put metastable supersymmetry breaking in a cosmological context. I argue that under reasonable assumptions, the cooling down early Universe favors metastable SUSY-breaking vacua over the stable supersymmetric vacua. To illustrate the general argument, I analyze the early-Universe history of the Intriligator-Seiberg-Shih model
4. The new break-even analysis.
Science.gov (United States)
2013-12-01
Changes in the economic and legislative environment have complicated the capital acquisition landscape. Hospitals and health systems should: Question the assumptions that underlie their break-even analysis. Revamp the break-even calculator. Engage in discussions about the clinical aspects of equipment and technology acquisition decisions.
5. Strongly coupled semidirect mediation of supersymmetry breaking
International Nuclear Information System (INIS)
Ibe, M.; Izawa, K.-I.; Nakai, Y.
2009-01-01
Strongly coupled semidirect gauge mediation models of supersymmetry breaking through massive mediators with standard-model charges are investigated by means of composite degrees of freedom. Sizable mediation is realized to generate the standard-model gaugino masses for a small mediator mass without breaking the standard-model symmetries.
6. Multiscale Simulation of Breaking Wave Impacts
DEFF Research Database (Denmark)
Lindberg, Ole
compare reasonably well. The incompressible and inviscid ALE-WLS model is coupled with the potential flow model of Engsig-Karup et al. [2009], to perform multiscale calculation of breaking wave impacts on a vertical breakwater. The potential flow model provides accurate calculation of the wave...... with a potential flow model to provide multiscale calculation of forces from breaking wave impacts on structures....
7. Nick translation detection in situ of cellular DNA strand break induced by radiation
International Nuclear Information System (INIS)
Maehara, Y.; Anai, H.; Kusumoto, T.; Sakaguchi, Y.; Sugimachi, K.
1989-01-01
DNA strand break in HeLa cells induced by radiation was detected using the in situ nick translation method. The cells were exposed to radiation of 3, 6, 12, 18, and 24 Gy in Lab-Tek tissue culture chamber/slides and were fixed with ethanol/acetic acid on the slide glass. The break sites in DNA were translated artificially in the presence of Escherichia coli DNA polymerase I and [ 3 H]-labeled dTTP. Autoradiographic observation was made of the level of break sites in the DNA. The DNA strand break appeared even with a 3 Gy exposure, increased 8.6 times at 24 Gy compared with the control cells, and this level correlated reciprocally to change in cell viability. This nick translation method provides a rapid in situ assay for determining radiation-induced DNA damage of cultured cells, in a semi-quantitative manner
8. Research progress on dam-break floods
KAUST Repository
Wu, Jiansong; Bao, Kai; Zhang, Hui
2011-01-01
Because of the catastrophic effects downstream of dam-break failure, more and more researchers around the world have been working on the study of dam-break flows to accurately forecast the downstream inundation mapping. With the rapid development of computer hardware and computing techniques, numerical study on dam-break flows has been a popular research subject. In the paper, the numerical methodologies used to solve the governing partial differential equations of dam-break flows are classified and summarized, and their characteristics and applications are discussed respectively. Furthermore, the fully-developed mathematical models developed in recent decades are reviewed, and also introduced the authors' on-going work. Finally, some possible future developments on modeling the dam-break flows and some solutions are presented and discussed. © 2011 IEEE.
9. Dynamical study of symmetries: breaking and restauration
International Nuclear Information System (INIS)
Schuck, P.
1986-09-01
First symmetry breaking (spontaneous) is explained and the physical implication discussed for infinite systems. The relation with phase transitions is indicated. Then the specific aspects of symmetry breaking in finite systems is treated and illustrated in detail for the case of translational invariance with the help of an oversimplified but exactly solvable model. The method of projection (restauration of symmetry) is explained for the static case and also applied to the model. Symmetry breaking in the dynamical case and for instance the notion of a soft mode responsible for the symmetry breaking is discussed in the case of superfluidity and another exactly solvable model is introduced. The Goldstone mode is treated in detail. Some remarks on analogies with the breaking of chiral symmetry are made. Some recent developments in the theory of symmetry restauration are briefly outlined [fr
10. Research progress on dam-break floods
KAUST Repository
Wu, Jiansong
2011-08-01
Because of the catastrophic effects downstream of dam-break failure, more and more researchers around the world have been working on the study of dam-break flows to accurately forecast the downstream inundation mapping. With the rapid development of computer hardware and computing techniques, numerical study on dam-break flows has been a popular research subject. In the paper, the numerical methodologies used to solve the governing partial differential equations of dam-break flows are classified and summarized, and their characteristics and applications are discussed respectively. Furthermore, the fully-developed mathematical models developed in recent decades are reviewed, and also introduced the authors\\' on-going work. Finally, some possible future developments on modeling the dam-break flows and some solutions are presented and discussed. © 2011 IEEE.
11. Chiral symmetry and chiral-symmetry breaking
International Nuclear Information System (INIS)
Peskin, M.E.
1982-12-01
These lectures concern the dynamics of fermions in strong interaction with gauge fields. Systems of fermions coupled by gauge forces have a very rich structure of global symmetries, which are called chiral symmetries. These lectures will focus on the realization of chiral symmetries and the causes and consequences of thier spontaneous breaking. A brief introduction to the basic formalism and concepts of chiral symmetry breaking is given, then some explicit calculations of chiral symmetry breaking in gauge theories are given, treating first parity-invariant and then chiral models. These calculations are meant to be illustrative rather than accurate; they make use of unjustified mathematical approximations which serve to make the physics more clear. Some formal constraints on chiral symmetry breaking are discussed which illuminate and extend the results of our more explicit analysis. Finally, a brief review of the phenomenological theory of chiral symmetry breaking is presented, and some applications of this theory to problems in weak-interaction physics are discussed
12. Big break for charge symmetry
CERN Document Server
Miller, G A
2003-01-01
Two new experiments have detected charge-symmetry breaking, the mechanism responsible for protons and neutrons having different masses. Symmetry is a crucial concept in the theories that describe the subatomic world because it has an intimate connection with the laws of conservation. The theory of the strong interaction between quarks - quantum chromodynamics - is approximately invariant under what is called charge symmetry. In other words, if we swap an up quark for a down quark, then the strong interaction will look almost the same. This symmetry is related to the concept of sup i sospin sup , and is not the same as charge conjugation (in which a particle is replaced by its antiparticle). Charge symmetry is broken by the competition between two different effects. The first is the small difference in mass between up and down quarks, which is about 200 times less than the mass of the proton. The second is their different electric charges. The up quark has a charge of +2/3 in units of the proton charge, while ...
13. Breaking rocks made easy: subcritical processes and tectonic predesign
Science.gov (United States)
Voigtlaender, Anne; Krautblatter, Michael
2017-04-01
In geomorphic studies, to change in landforms, e.g. by rock slope failure, fluvial or glacial erosion, a threshold is commonly assumed, which is crossed either by an increase in external driving or a decrease of internal resisting forces, respectively. If the threshold is crossed, bedrock breaks and slope fails, rivers incise and glaciers plug and sew their bed. Here we put forward a focus on the decrease of the resisting forces, as an increase in the driving forces, to match the strength of bedrock, is not that likely. We suggest that the degradation of resisting forces of bedrock can be better explained by subcritical processes like creep, fatigue and stress corrosion interplaying with tectonic predesign. Both concepts, subcritical processes and tectonic predesign have been issued in the last century, but have not been widely accepted nor have their assumptions been explicitly stressed in recent case studies. Moreover both concepts profit especially on scale issues if merged. Subcritical crack growth, includes different mechanisms promoting fractures well below the ultimate strength. Single infinitesimal but irreversible damage and deformations are induced in the material over time. They interact with inherent microstructural flaws and low applied stresses, limiting local strength and macroscopic behavior of bedrock. This reissues the concept of tectonic predesigned, as proposed by A.E. Scheidegger, which not only encompasses structural features that determine the routing of drainage patterns and shear planes, e.g. joints, faults and foliations, but also the (neo)tectonic stress-field and the (in-situ) strain state of bedrocks and mountains. Combining subcritical processes and tectonic predesign we can better explain, why and where we see a dissected, eroded and geomorphic divers' landscape. In this conceptual framework actual magnitudes of the driving forces are accounted for and so is the nature of the bedrock material, to better understand the trajectories of
14. Improving long term driving comfort by taking breaks - How break activity affects effectiveness.
Science.gov (United States)
Sammonds, George M; Mansfield, Neil J; Fray, Mike
2017-11-01
During long duration journeys, drivers are encouraged to take regular breaks. The benefits of breaks have been documented for safety; breaks may also be beneficial for comfort. The activity undertaken during a break may influence its effectiveness. Volunteers completed 3 journeys on a driving simulator. Each 130 min journey included a 10 min break after the first hour. During the break volunteers either stayed seated, left the simulator and sat in an adjacent room, or took a walk on a treadmill. The results show a reduction in driver discomfort during the break for all 3 conditions, but the effectiveness of the break was dependent on activity undertaken. Remaining seated in the vehicle provided some improvement in comfort, but more was experienced after leaving the simulator and sitting in an adjacent room. The most effective break occurred when the driver walked for 10 min on a treadmill. The benefits from taking a break continued until the end of the study (after a further hour of driving), such that comfort remained the best after taking a walk and worst for those who remained seated. It is concluded that taking a break and taking a walk is an effective method for relieving driving discomfort. Copyright © 2017 Elsevier Ltd. All rights reserved.
15. Yield of radiation-induced DNA single-strand breaks in Escherichia coli and superinfecting phage lambda at different dose rates. Repair of strand breaks in different buffers
International Nuclear Information System (INIS)
Boye, E.; Johansen, I.; Brustad, T.
1976-01-01
Cells of E. coli K-12 strain AB 1886 were irradiated in oxygenated phosphate buffered saline at 2 0 C with electrons from a 4-MeV linear accelerator. The yield of DNA single-strand breaks was determined as a function of the dose rate between 2.5 and 21,000 krad/min. For dose rates over 100 krad/min the yield was found to be constant. Below 10 krad/min the yield of breaks decreases drastically. This is explained by rejoining of breaks during irradiation. Twenty percent of the breaks induced by acute exposure are repaired within 3 min at 2 0 C. Superinfecting phage lambda DNA is repaired at the same rate as chromosomal DNA. In contrast to the results obtained with phosphate-buffered saline, an increase in the number of breaks after irradiation is observed when the bacteria are suspended in tris buffer. It is suggested that buffers of low ionic strength facilitate the leakage through the membrane of a small-molecular-weight component(s) necessary for DNA strand rejoining
16. Strength measurement of optical fibers by bending
Science.gov (United States)
Srubshchik, Leonid S.
1999-01-01
A two-point bending technique has been used not only to measure the breaking stress of optical fiber but also to predict its static and dynamic fatigue. The present theory of this test is based on elastica theory of rod. However, within the limits of elastica theory the tensile and shear stresses cannot be determined. In this paper we study dynamic and static problems for optical fiber in the two- point bending test on the base of geometrically exact theory in which rod can suffer flexure, extension, and shear. We obtain the governing partial differential equations taking into account the fact that the lateral motion of the fiber is restrained by the presence of flat parallel plates. We develop the computational methods for solving the initial and equilibrium free-boundary nonlinear planar problems. We derive the formulas for predicting of the tensile strength from strength in the bending and calculate one example.
17. Give Me Strength.
Institute of Scientific and Technical Information of China (English)
维拉
1996-01-01
Mort had an absolutely terrible day at the office.Everythingthat could go wrong did go wrong.As he walked home he could beheard muttering strange words to himself:“Oh,give me strength,give me strength.”Mort isn’t asking for the kind of strength thatbuilds strong muscles:he’s asking for the courage or ability to
18. Science Illiteracy: Breaking the Cycle
Science.gov (United States)
Lebofsky, L. A.; Lebofsky, N. R.
2003-12-01
At the University of Arizona, as at many state universities and colleges, the introductory science classes for non-science majors may be the only science classes that future K--8 teachers will take. The design of the UA's General Education program requires all future non-science certified teachers to take the General Education science classes. These classes are therefore an ideal venue for the training of the state's future teachers. Many students, often including future teachers, are ill-prepared for college, i.e., they lack basic science content knowledge, basic mathematics skills, and reading and writing skills. They also lack basic critical thinking skills and study skills. It is within this context that our future teachers are trained. How do we break the cycle of science illiteracy? There is no simple solution, and certainly not a one-size-fits-all panacea that complements every professor's style of instruction. However, there are several programs at the University of Arizona, and also principles that I apply in my own classes, that may be adaptable in other classrooms. Assessment of K--12 students' learning supports the use of inquiry-based science instruction. This approach can be incorporated in college classes. Modeling proven and productive teaching methods for the future teachers provides far more than `just the facts,'' and all students gain from the inquiry approach. Providing authentic research opportunities employs an inquiry-based approach. Reading (outside the textbook) and writing provide feedback to students with poor writing and critical thinking skills. Using peer tutors and an instant messaging hot line gives experience to the tutors and offers "comfortable" assistance to students.
19. Dynamical Symmetry Breaking of Extended Gauge Symmetries
OpenAIRE
Appelquist, Thomas; Shrock, Robert
2003-01-01
We construct asymptotically free gauge theories exhibiting dynamical breaking of the left-right, strong-electroweak gauge group $G_{LR} = {\\rm SU}(3)_c \\times {\\rm SU}(2)_L \\times {\\rm SU}(2)_R \\times {\\rm U}(1)_{B-L}$, and its extension to the Pati-Salam gauge group $G_{422}={\\rm SU}(4)_{PS} \\times {\\rm SU}(2)_L \\times {\\rm SU}(2)_R$. The models incorporate technicolor for electroweak breaking, and extended technicolor for the breaking of $G_{LR}$ and $G_{422}$ and the generation of fermion ...
20. Spontaneous symmetry breaking and its cosmological consequences
International Nuclear Information System (INIS)
Kobzarev, I.Yu.
1975-01-01
The concept of symmetry and of the spontaneous symmetry breaking are presented in popular form as applied to quantum physics. Though the presence of the spontaneous symmetry breaking is not proved directly for interactions of elementary particles, on considering the hypothesis of its presence as applied to the hot Universe theory a possibility of obtaining rather uncommon cosmological consequences is discussed. In particular, spontaneous symmetry breaking of vacuum and the rather hot Universe lead necessarily to the presence of the domain structure of the Universe with the surfase energy at the domain interface in the form of a real physical object
1. Supersymmetry Breaking through Transparent Extra Dimensions
Energy Technology Data Exchange (ETDEWEB)
Schmaltz, Martin
1999-11-23
We propose a new framework for mediating supersymmetry breaking through an extra dimension. It predicts positive scalar masses and solves the supersymmetric flavor problem. Supersymmetry breaks on a ''source'' brane that is spatially separated from a parallel brane on which the standard model matter fields and their superpartners live. The gauge and gaugino fields propagate in the bulk, the latter receiving a supersymmetry breaking mass from direct couplings to the source brane. Scalar masses are suppressed at the high scale but are generated via the renormalization group. We briefly discuss the spectrum and collider signals for a range of compactification scales.
2. Reliability of nondestructive testing of metal strength properties for power equipment
International Nuclear Information System (INIS)
Bugaj, N.V.; Lebedev, A.A.; Sharko, A.V.
1985-01-01
Ultrasonic control which is a constituent part of a complex control system which includes specimen-free (by hardness) tests, random breaking tests and acoustic measurements is stUdied for its reliability with respect to strength properties of power-equipment metal. Quantitative and alternative criteria are developed to estimate quality of elements for power-equipment according to results of metal strength properties. Acoustic control results are presented for ultimate strength in 12Kh1MF-steel
3. Speckle dynamics under ergodicity breaking
Science.gov (United States)
Sdobnov, Anton; Bykov, Alexander; Molodij, Guillaume; Kalchenko, Vyacheslav; Jarvinen, Topias; Popov, Alexey; Kordas, Krisztian; Meglinski, Igor
2018-04-01
Laser speckle contrast imaging (LSCI) is a well-known and versatile approach for the non-invasive visualization of flows and microcirculation localized in turbid scattering media, including biological tissues. In most conventional implementations of LSCI the ergodic regime is typically assumed valid. However, most composite turbid scattering media, especially biological tissues, are non-ergodic, containing a mixture of dynamic and static centers of light scattering. In the current study, we examined the speckle contrast in different dynamic conditions with the aim of assessing limitations in the quantitative interpretation of speckle contrast images. Based on a simple phenomenological approach, we introduced a coefficient of speckle dynamics to quantitatively assess the ratio of the dynamic part of a scattering medium to the static one. The introduced coefficient allows one to distinguish real changes in motion from the mere appearance of static components in the field of view. As examples of systems with static/dynamic transitions, thawing and heating of Intralipid samples were studied by the LSCI approach.
4. Chain Ends and the Ultimate Tensile Strength of Polyethylene Fibers
Science.gov (United States)
O'Connor, Thomas C.; Robbins, Mark O.
Determining the tensile yield mechanisms of oriented polymer fibers remains a challenging problem in polymer mechanics. By maximizing the alignment and crystallinity of polyethylene (PE) fibers, tensile strengths σ ~ 6 - 7 GPa have been achieved. While impressive, first-principal calculations predict carbon backbone bonds would allow strengths four times higher (σ ~ 20 GPa) before breaking. The reduction in strength is caused by crystal defects like chain ends, which allow fibers to yield by chain slip in addition to bond breaking. We use large scale molecular dynamics (MD) simulations to determine the tensile yield mechanism of orthorhombic PE crystals with finite chains spanning 102 -104 carbons in length. The yield stress σy saturates for long chains at ~ 6 . 3 GPa, agreeing well with experiments. Chains do not break but always yield by slip, after nucleation of 1D dislocations at chain ends. Dislocations are accurately described by a Frenkel-Kontorova model, parametrized by the mechanical properties of an ideal crystal. We compute a dislocation core size ξ = 25 . 24 Å and determine the high and low strain rate limits of σy. Our results suggest characterizing such 1D dislocations is an efficient method for predicting fiber strength. This research was performed within the Center for Materials in Extreme Dynamic Environments (CMEDE) under the Hopkins Extreme Materials Institute at Johns Hopkins University. Financial support was provided by Grant W911NF-12-2-0022.
5. Anisotropic Concrete Compressive Strength
DEFF Research Database (Denmark)
Gustenhoff Hansen, Søren; Jørgensen, Henrik Brøner; Hoang, Linh Cao
2017-01-01
When the load carrying capacity of existing concrete structures is (re-)assessed it is often based on compressive strength of cores drilled out from the structure. Existing studies show that the core compressive strength is anisotropic; i.e. it depends on whether the cores are drilled parallel...
6. High strength ferritic alloy
International Nuclear Information System (INIS)
1977-01-01
A high strength ferritic steel is specified in which the major alloying elements are chromium and molybdenum, with smaller quantities of niobium, vanadium, silicon, manganese and carbon. The maximum swelling is specified for various irradiation conditions. Rupture strength is also specified. (U.K.)
7. Photon strength functions
International Nuclear Information System (INIS)
Bergqvist, I.
1976-01-01
Methods for extracting photon strength functions are briefly discussed. We follow the Brink-Axel approach to relate the strength functions to the giant resonances observed in photonuclear work and summarize the available data on the E1, E2 and M1 resonances. Some experimental and theoretical problems are outlined. (author)
8. Interviewing to Understand Strengths
Science.gov (United States)
Hass, Michael R.
2018-01-01
Interviewing clients about their strengths is an important part of developing a complete understanding of their lives and has several advantages over simply focusing on problems and pathology. Prerequisites for skillfully interviewing for strengths include the communication skills that emerge from a stance of not knowing, developing a vocabulary…
9. Dirac neutrino masses from generalized supersymmetry breaking
International Nuclear Information System (INIS)
Demir, D.A.; Everett, L.L.; Langacker, P.
2007-12-01
We demonstrate that Dirac neutrino masses in the experimentally preferred range are generated within supersymmetric gauge extensions of the Standard Model with a generalized supersymmetry breaking sector. If the usual superpotential Yukawa couplings are forbidden by the additional gauge symmetry (such as a U(1) ' ), effective Dirac mass terms involving the ''wrong Higgs'' field can arise either at tree level due to hard supersymmetry breaking fermion Yukawa couplings, or at one-loop due to nonanalytic or ''nonholomorphic'' soft supersymmetry breaking trilinear scalar couplings. As both of these operators are naturally suppressed in generic models of supersymmetry breaking, the resulting neutrino masses are naturally in the sub-eV range. The neutrino magnetic and electric dipole moments resulting from the radiative mechanism also vanish at one-loop order. (orig.)
10. Tidal Mixing at the Shelf Break
National Research Council Canada - National Science Library
Hogg, Nelson; Legg, Sonya
2005-01-01
The aim of this project was to study mixing forced by tidal flow over sudden changes in topographic slope such as near the shelf-break, using high-resolution nonhydrostatic numerical simulations employing the MIT gem...
11. Higgsless grand unified theory breaking and trinification
International Nuclear Information System (INIS)
Carone, Christopher D.; Conroy, Justin M.
2004-01-01
Boundary conditions on an extra dimensional interval can be chosen to break bulk gauge symmetries and to reduce the rank of the gauge group. We consider this mechanism in models with gauge trinification. We determine the boundary conditions necessary to break the trinified gauge group directly down to that of the standard model. Working in an effective theory for the gauge-symmetry-breaking parameters on a boundary, we examine the limit in which the grand-unified theory-breaking-sector is Higgsless and show how one may obtain the low-energy particle content of the minimal supersymmetric standard model. We find that gauge unification is preserved in this scenario, and that the differential gauge coupling running is logarithmic above the scale of compactification. We compare the phenomenology of our model to that of four dimensional 'trinified' theories
12. Water Breaking: Understand This Sign of Labor
Science.gov (United States)
Healthy Lifestyle Labor and delivery, postpartum care Water breaking worries? Prepare yourself for childbirth by getting the facts about this important sign of labor. By Mayo Clinic Staff If you're ...
13. On breaks of the Indian monsoon
R. Narasimhan (Krishtel eMaging) 1461 1996 Oct 15 13:05:22
quadrapole is a basic feature of weak spells of the intraseasonal variation over the Asia-west Pacific region. ... (Earth Planet. Sci.), 112 .... be useful to define the break monsoon (and active ... monsoon zone, different scientists have used the.
14. The problem of symmetry breaking hierarchy
International Nuclear Information System (INIS)
Natale, A.A.
1983-01-01
The problem of symmetry breaking hierarchy in grand unified theories is discussed, proving the impossibility to get a big hierarchy of interactions, in a natural way within the framework of perturbation theory. (L.C.) [pt
15. Tissue engineering
CERN Document Server
Fisher, John P; Bronzino, Joseph D
2007-01-01
Increasingly viewed as the future of medicine, the field of tissue engineering is still in its infancy. As evidenced in both the scientific and popular press, there exists considerable excitement surrounding the strategy of regenerative medicine. To achieve its highest potential, a series of technological advances must be made. Putting the numerous breakthroughs made in this field into a broad context, Tissue Engineering disseminates current thinking on the development of engineered tissues. Divided into three sections, the book covers the fundamentals of tissue engineering, enabling technologies, and tissue engineering applications. It examines the properties of stem cells, primary cells, growth factors, and extracellular matrix as well as their impact on the development of tissue engineered devices. Contributions focus on those strategies typically incorporated into tissue engineered devices or utilized in their development, including scaffolds, nanocomposites, bioreactors, drug delivery systems, and gene t...
16. Measuring Relative Coupling Strength in Circadian Systems.
Science.gov (United States)
Schmal, Christoph; Herzog, Erik D; Herzel, Hanspeter
2018-02-01
Modern imaging techniques allow the monitoring of circadian rhythms of single cells. Coupling between these single cellular circadian oscillators can generate coherent periodic signals on the tissue level that subsequently orchestrate physiological outputs. The strength of coupling in such systems of oscillators is often unclear. In particular, effects on coupling strength by varying cell densities, by knockouts, and by inhibitor applications are debated. In this study, we suggest to quantify the relative coupling strength via analyzing period, phase, and amplitude distributions in ensembles of individual circadian oscillators. Simulations of different oscillator networks show that period and phase distributions become narrower with increasing coupling strength. Moreover, amplitudes can increase due to resonance effects. Variances of periods and phases decay monotonically with coupling strength, and can serve therefore as measures of relative coupling strength. Our theoretical predictions are confirmed by studying recently published experimental data from PERIOD2 expression in slices of the suprachiasmatic nucleus during and after the application of tetrodotoxin (TTX). On analyzing the corresponding period, phase, and amplitude distributions, we can show that treatment with TTX can be associated with a reduced coupling strength in the system of coupled oscillators. Analysis of an oscillator network derived directly from the data confirms our conclusions. We suggest that our approach is also applicable to quantify coupling in fibroblast cultures and hepatocyte networks, and for social synchronization of circadian rhythmicity in rodents, flies, and bees.
17. Spontaneous symmetry breaking in N=3 supergravity
International Nuclear Information System (INIS)
Zinov'ev, Yu.M.
1986-01-01
The possibility of the spontaneous symmetry breaking without a cosmological term in N=3 supergravity is investigated. A new, dual version of N=3 supergravity - U(3)-supergravity is constructed. Such a theory is shown to admit a spontaneous supersymmetry breaking without a cosmological term and with three arbitrary scales, including partial super-Higgs effect N=3 → N=2 and N=3 → N=1
18. Why and How Java Developers Break APIs
OpenAIRE
Brito, Aline; Xavier, Laerte; Hora, Andre; Valente, Marco Tulio
2018-01-01
Modern software development depends on APIs to reuse code and increase productivity. As most software systems, these libraries and frameworks also evolve, which may break existing clients. However, the main reasons to introduce breaking changes in APIs are unclear. Therefore, in this paper, we report the results of an almost 4-month long field study with the developers of 400 popular Java libraries and frameworks. We configured an infrastructure to observe all changes in these libraries and t...
19. Lifshitz-sector mediated SUSY breaking
OpenAIRE
Pospelov, MaximDepartment of Physics and Astronomy, University of Victoria, Victoria, BC, V8P 5C2, Canada; Tamarit, Carlos(Perimeter Institute for Theoretical Physics, Waterloo, ON, N2L 2Y5, Canada)
2014-01-01
We propose a novel mechanism of SUSY breaking by coupling a Lorentz-invariant supersymmetric matter sector to non-supersymmetric gravitational interactions with Lifshitz scaling. The improved UV properties of Lifshitz propagators moderate the otherwise uncontrollable ultraviolet divergences induced by gravitational loops. This ensures that both the amount of induced Lorentz violation and SUSY breaking in the matter sector are controlled by {{{\\Lambda_{\\mathrm{HL}}^2}} \\left/ {{M_P^2}} \\righ... 20. Group theory of spontaneous symmetry breaking International Nuclear Information System (INIS) Ghaboussi, F. 1987-01-01 The connection between the minimality of the Higgs field potential and the maximal little groups of its representation obtained by spontaneous symmetry breaking is analyzed. It is shown that for several representations the lowest minimum of the potential is related to the maximal little group of those representations. Furthermore, a practical necessity criterion is given for the representation of the Higgs field needed for spontaneous symmetry breaking 1. Cooperation and competition between two symmetry breakings in a coupled ratchet Science.gov (United States) Li, Chen-Pu; Chen, Hong-Bin; Fan, Hong; Xie, Ge-Ying; Zheng, Zhi-Gang 2018-03-01 We investigate the collective mechanism of coupled Brownian motors in a flashing ratchet in the presence of coupling symmetry breaking and space symmetry breaking. The dependences of directed current on various parameters are extensively studied in terms of numerical simulations and theoretical analysis. Reversed motion can be achieved by modulating multiple parameters including the spatial asymmetry coefficient, the coupling asymmetry coefficient, the coupling free length and the coupling strength. The dynamical mechanism of these transport properties can be reasonably explained by the effective potential theory and the cooperation or competition between two symmetry breakings. Moreover, adjusting the Gaussian white noise intensity, which can induce weak reversed motion under certain condition, can optimize and manipulate the directed transport of the ratchet system. 2. Isospin-symmetry breaking in masses of N≃Z nuclei Directory of Open Access Journals (Sweden) P. Bączyk 2018-03-01 Full Text Available Effects of the isospin-symmetry breaking (ISB beyond mean-field Coulomb terms are systematically studied in nuclear masses near the N=Z line. The Coulomb exchange contributions are calculated exactly. We use extended Skyrme energy density functionals (EDFs with proton–neutron-mixed densities, to which we add new terms breaking the isospin symmetry. Two parameters associated with the new terms are determined by fitting mirror and triplet displacement energies (MDEs and TDEs of isospin multiplets. The new EDFs reproduce MDEs for the T=12 doublets and T=1 triplets, and TDEs for the T=1 triplets. Relative strengths of the obtained isospin-symmetry-breaking terms are not consistent with the differences in the NN scattering lengths, ann, app, and anp. Based on low-energy experimental data, it seems thus impossible to delineate the strong-force ISB effects from beyond-mean-field Coulomb-energy corrections. 3. Isospin-symmetry breaking in masses of N ≃ Z nuclei Science.gov (United States) Bączyk, P.; Dobaczewski, J.; Konieczka, M.; Satuła, W.; Nakatsukasa, T.; Sato, K. 2018-03-01 Effects of the isospin-symmetry breaking (ISB) beyond mean-field Coulomb terms are systematically studied in nuclear masses near the N = Z line. The Coulomb exchange contributions are calculated exactly. We use extended Skyrme energy density functionals (EDFs) with proton-neutron-mixed densities, to which we add new terms breaking the isospin symmetry. Two parameters associated with the new terms are determined by fitting mirror and triplet displacement energies (MDEs and TDEs) of isospin multiplets. The new EDFs reproduce MDEs for the T = 1/2 doublets and T = 1 triplets, and TDEs for the T = 1 triplets. Relative strengths of the obtained isospin-symmetry-breaking terms are not consistent with the differences in the NN scattering lengths, ann, app, and anp. Based on low-energy experimental data, it seems thus impossible to delineate the strong-force ISB effects from beyond-mean-field Coulomb-energy corrections. 4. The structure of GUT breaking by orbifolding International Nuclear Information System (INIS) Hebecker, Arthur; March-Russell, John 2002-01-01 Recently, an attractive model of GUT breaking has been proposed in which a 5-dimensional supersymmetric SU(5) gauge theory on an S 1 /(Z 2 xZ 2 ') orbifold is broken down to the 4d MSSM by SU(5)-violating boundary conditions. Motivated by this construction and several related realistic models, we investigate the general structure of orbifolds in the effective field theory context, and of this orbifold symmetry breaking mechanism in particular. An analysis of the group theoretic structure of orbifold breaking is performed. This depends upon the existence of appropriate inner and outer automorphisms of the Lie algebra, and we show that a reduction of the rank of the GUT group is possible. Some aspects of larger GUT theories based on SO(10) and E 6 are discussed. We explore the possibilities of defining the theory directly on a space with boundaries and breaking the gauge symmetry by more general consistently chosen boundary conditions for the fields. Furthermore, we derive the relation of orbifold breaking with the familiar mechanism of Wilson line breaking, finding a one-to-one correspondence, both conceptually and technically. Finally, we analyse the consistency of orbifold models in the effective field theory context, emphasizing the necessity for self-adjoint extensions of the Hamiltonian and other conserved operators, and especially the highly restrictive anomaly cancellation conditions that apply if the bulk theory lives in more than 5 dimensions 5. The spontaneous ℤ_2 breaking Twin Higgs International Nuclear Information System (INIS) Beauchesne, Hugues; Earl, Kevin; Grégoire, Thomas 2016-01-01 The Twin Higgs model seeks to address the little hierarchy problem by making the Higgs a pseudo-Goldstone of a global SU(4) symmetry that is spontaneously broken to SU(3). Gauge and Yukawa couplings, which explicitly break SU(4), enjoy a discrete ℤ_2 symmetry that accidentally maintains SU(4) at the quadratic level and therefore keeps the Higgs light. Contrary to most beyond the Standard Model theories, the quadratically divergent corrections to the Higgs mass are cancelled by a mirror sector, which is uncharged under the Standard Model groups. However, the Twin Higgs with an exact ℤ_2 symmetry leads to equal vevs in the Standard Model and mirror sectors, which is phenomenologically unviable. An explicit ℤ_2 breaking potential must then be introduced and tuned against the SU(4) breaking terms to produce a hierarchy of vevs between the two sectors. This leads to a moderate but non-negligible tuning. We propose a model to alleviate this tuning, without the need for an explicit ℤ_2 breaking sector. The model consists of two SU(4) fundamental Higgses, one whose vacuum preserves ℤ_2 and one whose vacuum breaks it. As the interactions between the two Higgses are turned on, the ℤ_2 breaking is transmitted from the broken to the unbroken sector and a small hierarchy of vevs is naturally produced. The presence of an effective tadpole and feedback between the two Higgses lead to a sizable improvement of the tuning. The resulting Higgs boson is naturally very Standard Model like. 6. The breaking of flavor democracy in the quark sector Science.gov (United States) Fritzsch, Harald; Xing, Zhi-Zhong; Zhang, Di 2017-09-01 The democracy of quark flavors is a well-motivated flavor symmetry, but it must be properly broken in order to explain the observed quark mass spectrum and flavor mixing pattern. We reconstruct the texture of flavor democracy breaking and evaluate its strength in a novel way, by assuming a parallelism between the Q=+2/3 and Q=-1/3 quark sectors and using a nontrivial parametrization of the flavor mixing matrix. Some phenomenological implications of such democratic quark mass matrices, including their variations in the hierarchy basis and their evolution from the electroweak scale to a super-high energy scale, are also discussed. Supported by National Natural Science Foundation of China (11375207) and National Basic Research Program of China (2013CB834300) 7. GUT scale and superpartner masses from anomaly mediated supersymmetry breaking International Nuclear Information System (INIS) Chacko, Z.; Luty, Markus A.; Ponton, Eduardo; Shadmi, Yael; Shirman, Yuri 2001-01-01 We consider models of anomaly-mediated supersymmetry breaking (AMSB) in which the grand unification (GUT) scale is determined by the vacuum expectation value of a chiral superfield. If the anomaly-mediated contributions to the potential are balanced by gravitational-strength interactions, a GUT scale of M Planck /(16π 2 ) can be generated. The GUT threshold also affects superpartner masses, and can easily give rise to realistic predictions if the GUT gauge group is asymptotically free. We give an explicit example of a model with these features, in which the doublet-triplet splitting problem is solved. The resulting superpartner spectrum is very different from that of previously considered AMSB models, with gaugino masses typically unifying at the GUT scale 8. Study of projectile break-up process at intermediate energies International Nuclear Information System (INIS) Kumar, Harish; Parashari, Siddharth; Tali, Suhail A. 2016-01-01 The projectile break-up reactions are explained in terms of incomplete fusion or massive transfer reactions leading to the formation of composite system with less mass, charge and excitation energy, as compared to the complete fusion (CF) process. Since, the existing theoretical models are not applicable to reproduce the experimentally measured ICF, data satisfactory below 10 MeV/nucleon energies; thereby the study of the role of the entrance channel parameters in the fusion reactions is still a relevant problem in establishing the explicit inference regarding the influence of ICF on CF at 4-7 MeV/nucleon energies. Recently reported some studies have also shown that alpha Q-value is also an important parameter which affects the onset of ICF and conflict with the suggestion of Morgenstern et al. Keeping in view the recent aspects, to provide more strength to the aspect of projectile-target mass-asymmetry effect, role of non α-cluster projectile over α-cluster projectile, the present work has been carried out which will be useful to understand a clearer picture about the conflict between mass-asymmetry and projectile structure effect on break-up fusion process. As such, excitation function measurement of residues produced in 13 C + 175 Lu system has been carried out in a series of experiments of comparative study using α-cluster as well as non α-cluster projectiles with deformed heavier target nuclei at lower projectile energies ≈ 4-7 MeV/nucleon 9. Microablation of collagen-based substrates for soft tissue engineering International Nuclear Information System (INIS) Kumar, Vivek A; Caves, Jeffrey M; Naik, Nisarga; Haller, Carolyn A; Chaikof, Elliot L; Martinez, Adam W 2014-01-01 Noting the abundance and importance of collagen as a biomaterial, we have developed a facile method for the production of a dense fibrillar extracellular matrix mimicking collagen–elastin hybrids with tunable mechanical properties. Through the use of excimer-laser technology, we have optimized conditions for the ablation of collagen lamellae without denaturation of protein, maintenance of fibrillar ultrastructure and preservation of native D-periodicity. Strengths of collagen–elastin hybrids ranged from 0.6 to 13 MPa, elongation at break from 9 to 70% and stiffness from 2.9 to 94 MPa, allowing for the design of a wide variety of tissue specific scaffolds. Further, large (centimeter scale) lamellae can be fabricated and embedded with recombinant elastin to generate collagen–elastin hybrids. Exposed collagen in hybrids act as cell adhesive sites for rat mesenchymal stem cells that conform to ablate waveforms. The ability to modulate these features allows for the generation of a class of biopolymers that can architecturally and physiologically replicate native tissue. (communication) 10. Spontaneous symmetry breaking in ΡΤ symmetric systems with nonlinear damping International Nuclear Information System (INIS) Karthiga, S.; Chandrasekar, V.K.; Senthilvelan, M.; Lakshmanan, M. 2016-01-01 In this talk, we discuss the remarkable role of position dependent damping in determining the parametric regions of symmetry breaking in nonlinear ΡΤ -symmetric systems. We illustrate the nature of ΡΤ-symmetry preservation and breaking with reference to a remarkable integrable scalar nonlinear system. In the two dimensional cases of such position dependent damped systems, we unveil the existence of a class of novel bi-ΡΤ -symmetric systems which have two fold ΡΤ symmetries. We discuss the dynamics of these systems and show how symmetry breaking occurs, that is whether the symmetry breaking of the two ΡΤ symmetries occurs in pair or occurs one by one. The addition of linear damping in these nonlinearly damped systems induces competition between the two types of damping. This competition results in a ΡΤ phase transition in which the ΡΤ symmetry is broken for lower loss/gain strength and is restored by increasing the loss/gain strength. We also show that by properly designing the form of the position dependent damping, we can tailor the ΡΤ-symmetric regions of the system. (author) 11. No struggle, no strength DEFF Research Database (Denmark) Morgall, Janine Marie; Almarsdóttir, Anna Birna 1999-01-01 Research accounts of the struggle of professions to attain and maintain a monopoly, strategies of exclusion and usurpation, make for interesting and often exciting reading. The purpose of this article is to present a less frequently reported phenomenon--the study of a profession that had a monopoly......, and then lost it. The authors attempt to answer the question: under what circumstances will a profession support the state in breaking their own monopoly? The study looked at the pharmacy profession in Iceland in the light of the recent change in drug legislation. Interviews with key actors in the pharmacy...... profession were conducted to gain an understanding of how they interpreted and experienced this change. Three factors contributed to the break in the professional monopoly: (1) political desire to take advantage of new competition and deregulation policy, (2) desire to cut the health budget and (3) internal... 12. Tissue types (image) Science.gov (United States) ... are 4 basic types of tissue: connective tissue, epithelial tissue, muscle tissue, and nervous tissue. Connective tissue supports ... binds them together (bone, blood, and lymph tissues). Epithelial tissue provides a covering (skin, the linings of the ... 13. Breaking of axial symmetry in excited heavy nuclei as identified in giant dipole resonance data Energy Technology Data Exchange (ETDEWEB) Grosse, E.; Massarczyk, R. [Technische Universitaet Dresden, Institute of Nuclear and Particle Physics, Dresden (Germany); Junghans, A.R. [Helmholtz-Zentrum Dresden-Rossendorf, Institute of Radiation Physics, Dresden (Germany) 2017-11-15 A recent theoretical prediction of a breaking of axial symmetry in quasi all heavy nuclei is confronted to a new critical analysis of photon strength functions of nuclei in the valley of stability. For the photon strength in the isovector giant dipole resonance (IVGDR) regime a parameterization of GDR shapes by the sum of three Lorentzians (TLO) is extrapolated to energies below and above the IVGDR. The impact of non-GDR modes adding to the low energy slope of photon strength is discussed including recent data on photon scattering and other radiative processes. These are shown to be concentrated in energy regions where various model calculations predict intermediate collective strength; thus they are obviously separate from the IVGDR tail. The triple Lorentzian (TLO) ansatz for giant dipole resonances is normalized in accordance to the dipole sum rule. The nuclear droplet model with surface dissipation accounts well for positions and widths without local, nuclide specific, parameters. Very few and only global parameters are needed when a breaking of axial symmetry already in the valley of stability is admitted and hence a reliable prediction for electric dipole strength functions also outside of it is expected. (orig.) 14. Radiotherapy in patients with connective tissue diseases. Science.gov (United States) Giaj-Levra, Niccolò; Sciascia, Savino; Fiorentino, Alba; Fersino, Sergio; Mazzola, Rosario; Ricchetti, Francesco; Roccatello, Dario; Alongi, Filippo 2016-03-01 The decision to offer radiotherapy in patients with connective tissue diseases continues to be challenging. Radiotherapy might trigger the onset of connective tissue diseases by increasing the expression of self-antigens, diminishing regulatory T-cell activity, and activating effectors of innate immunity (dendritic cells) through Toll-like receptor-dependent mechanisms, all of which could potentially lead to breaks of immune tolerance. This potential risk has raised some debate among radiation oncologists about whether patients with connective tissue diseases can tolerate radiation as well as people without connective tissue diseases. Because the number of patients with cancer and connective tissue diseases needing radiotherapy will probably increase due to improvements in medical treatment and longer life expectancy, the issue of interactions between radiotherapy and connective tissue diseases needs to be clearer. In this Review, we discuss available data and evidence for patients with connective tissue diseases treated with radiotherapy. Copyright © 2016 Elsevier Ltd. All rights reserved. 15. Relating wood properties to handsheet porosity and mechanical strength CSIR Research Space (South Africa) Maharaj, S 2006-11-01 Full Text Available , 4041 3CSIR, Forestry and Forest Products Research Centre, P.O. Box 17001, Congella, 4013 WOOD HAND-SHEET (STRENGTH) PROCESSING Anatomy Chemistry Density Tear Tensile Burst Background Variation in pulp mills •Need to predict quality of end... important concepts… Some important concepts… • Collapsibility and inter-fibre bonding Light Microscopy SEM • Tear – Fibre level: pull-out vs. breaking/rupture Some important concepts… •Fibre breakage / rupture: less energy = lower tear strength... 16. Laser-tissue soldering with biodegradable polymer films in vitro: film surface morphology and hydration effects. Science.gov (United States) Sorg, B S; Welch, A J 2001-01-01 Previous research introduced the concept of using biodegradable polymer film reinforcement of a liquid albumin solder for improvement of the tensile strength of repaired incisions in vitro. In this study, the effect of creating small pores in the PLGA films on the weld breaking strength is studied. Additionally, the effect of hydration on the strength of the reinforced welds is investigated. A 50%(w/v) bovine serum albumin solder with 0.5 mg/mL Indocyanine Green dye was used to repair an incision in bovine aorta. The solder was coagulated with an 806-nm CW diode laser. A poly(DL-lactic-co-glycolic acid) (PLGA) film was used to reinforce the solder (the controls had solder but no reinforcement). Breaking strengths were measured acutely and after hydration in saline for 1 and 2 days. The data were analyzed by ANOVA (P < 0.05) and multiple comparisons of means were performed using the Newman-Keuls test. The creation of pores in the PLGA films qualitatively improved the film flexibility without having an apparent adverse effect on the breaking strength, while the actual technique of applying the film and solder had more of an effect. The acute maximum average breaking strengths of some of the film reinforced specimens (114.7 g-134.4 g) were significantly higher (P < 0.05) than the acute maximum average breaking strength of the unreinforced control specimens (68.3 g). Film reinforced specimens were shown to have a statistically significantly higher breaking strength than unreinforced controls after 1- and 2-day hydration. Reinforcement of liquid albumin solders in laser-assisted incision repair appears to have advantages over conventional methods that do not reinforce the cohesive strength of the solder in terms of acute breaking strength and after immersion in moist environments for short periods of time. Using a film with the solder applied to one surface only may be advantageous over other techniques. 17. Modelling oil price volatility with structural breaks International Nuclear Information System (INIS) Salisu, Afees A.; Fasanya, Ismail O. 2013-01-01 In this paper, we provide two main innovations: (i) we analyze oil prices of two prominent markets namely West Texas Intermediate (WTI) and Brent using the two recently developed tests by Narayan and Popp (2010) and Liu and Narayan, 2010 both of which allow for two structural breaks in the data series; and (ii) the latter method is modified to include both symmetric and asymmetric volatility models. We identify two structural breaks that occur in 1990 and 2008 which coincidentally correspond to the Iraqi/Kuwait conflict and the global financial crisis, respectively. We find evidence of persistence and leverage effects in the oil price volatility. While further extensions can be pursued, the consideration of asymmetric effects as well as structural breaks should not be jettisoned when modelling oil price volatility. - Highlights: ► We analyze oil price volatility using NP (2010) and LN (2010) tests. ► We modify the LN (2010) to account for leverage effects in oil price. ► We find two structural breaks that reflect major global crisis in the oil market. ► We find evidence of persistence and leverage effects in oil price volatility. ► Leverage effects and structural breaks are fundamental in oil price modelling. 18. Infliximab's influence on anastomotic strength and degree of inflammation in intestinal surgery in a rabbit model DEFF Research Database (Denmark) Frostberg, Erik; Ström, Petter; Gerke, Oke 2014-01-01 and conclusions. The purpose of this study was to investigate whether a single dose infliximab has an adverse effect on the anastomotic healing process, observed as reduced anastomotic breaking strength and histopathologically verified lower grade of inflammatory response, in the small intestine of a rabbit....... METHODS: Thirty New Zealand rabbits (median weight 2.5 kg) were allocated to treatment with an intravenous bolus of either 10 mg/kg infliximab (n = 15) or placebo (n = 15). One week later all rabbits underwent two separate end-to-end anastomoses in the jejunum under general anesthesia. At postoperative...... day three, the anastomotic breaking strength was determined and histopathological changes were examined. RESULTS: The mean value of anastomotic breaking strength in the placebo group was 1.89 +/- 0.36 N and the corresponding value was 1.81 +/- 0.33 N in the infliximab treated rabbits... 19. 9 CFR 590.522 - Breaking room operations. Science.gov (United States) 2010-01-01 ... personnel. (m) Ingredients and additives used in, or for, processing egg products, shall be handled in a..., Processing, and Facility Requirements § 590.522 Breaking room operations. (a) The breaking room shall be kept... clean and reasonably dry during breaking operations and free of egg meat and shells. (b) All breaking... 20. Jet simulations and gamma-ray burst afterglow jet breaks NARCIS (Netherlands) van Eerten, H.J.; Meliani, Z.; Wijers, R.A.M.J.; Keppens, R. 2011-01-01 The conventional derivation of the gamma-ray burst afterglow jet break time uses only the blast wave fluid Lorentz factor and therefore leads to an achromatic break. We show that in general gamma-ray burst afterglow jet breaks are chromatic across the self-absorption break. Depending on 1. Jet simulations and gamma-ray burst afterglow jet breaks NARCIS (Netherlands) van Eerten, H. J.; Meliani, Z.; Wijers, R.A.M.J.; Keppens, R. 2010-01-01 The conventional derivation of the gamma-ray burst afterglow jet break time uses only the blast wave fluid Lorentz factor and therefore leads to an achromatic break. We show that in general gamma-ray burst afterglow jet breaks are chromatic across the self-absorption break. Depending on 2. Hydraulic Response of Caisson Breakwaters in Multidirectional Breaking and Non-Breaking Waves DEFF Research Database (Denmark) Grønbech, J.; Kofoed, Jens Peter; Hald, Tue 1998-01-01 The present paper concerns the results and findings of a physical study on wave impacts on vertical caisson breakwaters situated in irregular, multidirectional breaking seas. The study has taken place as part of the framework programme "Dynamic of Structures" financially supported by the Danish T...... breaking waves at deep water. The study on wave overtopping showed that the 3D wave overtopping formula suggested by Franco et al., 1995b, predicts the wave overtopping reasonable well for both non breaking and breaking waves at deep water.......The present paper concerns the results and findings of a physical study on wave impacts on vertical caisson breakwaters situated in irregular, multidirectional breaking seas. The study has taken place as part of the framework programme "Dynamic of Structures" financially supported by the Danish...... induced loading and overtopping on caisson breakwaters situated in breaking seas. Regarding the wave forces only minor differences between breaking and non breaking waves in deep water were observed, and it was found that the prediction formula of Goda also seems to apply well for multidirectionally... 3. Break-glass handling exceptional situations in access control CERN Document Server Petritsch, Helmut 2014-01-01 Helmut Petritsch describes the first holistic approach to Break-Glass which covers the whole life-cycle: from access control modeling (pre-access), to logging the security-relevant system state during Break-Glass accesses (at-access), and the automated analysis of Break-Glass accesses (post-access). Break-Glass allows users to override security restrictions in exceptional situations. While several Break-Glass models specific to given access control models have already been discussed in research (e.g., extending RBAC with Break-Glass), the author introduces a generic Break-Glass model. The pres 4. U(1) mediation of flux supersymmetry breaking Science.gov (United States) Grimm, Thomas W.; Klemm, Albrecht 2008-10-01 We study the mediation of supersymmetry breaking triggered by background fluxes in Type II string compactifications with Script N = 1 supersymmetry. The mediation arises due to an U(1) vector multiplet coupling to both a hidden supersymmetry breaking flux sector and a visible D-brane sector. The required internal manifolds can be constructed by non-Kähler resolutions of singular Calabi-Yau manifolds. The effective action encoding the U(1) coupling is then determined in terms of the global topological properties of the internal space. We investigate suitable local geometries for the hidden and visible sector in detail. This includes a systematic study of orientifold symmetries of del Pezzo surfaces realized in compact geometries after geometric transition. We construct compact examples admitting the key properties to realize flux supersymmetry breaking and U(1) mediation. Their toric realization allows us to analyze the geometry of curve classes and confirm the topological connection between the hidden and visible sector. 5. Report of Break Out Group 1 DEFF Research Database (Denmark) Alward, Randy; Carley, Kathleen M.; Madsen, Fredrik Huitfeldt 2006-01-01 , action" (OODA) loop. The break out group discussed vulnerability presentation needs common across various application domains, particularly in support of network discovery and network analysis tasks in those domains. Finally, the break out group wished to determine whether there is a means...... of characterizing a vulnerability. This would take into account the potential for the vulnerability to be exploited as well as the potential impact on the operations supported by the network, and on the network structure itself, of a successful exploit of that vulnerability.......To help understand a network and its ability to continue operating when under attack, the break out group discussed issues that need to be considered when presenting network vulnerability information to an analyst, manager or commander in effective support of that person's "observe, orient, decide... 6. U(1) mediation of flux supersymmetry breaking International Nuclear Information System (INIS) Grimm, Thomas W.; Klemm, Albrecht 2008-01-01 We study the mediation of supersymmetry breaking triggered by background fluxes in Type II string compactifications with N = 1 supersymmetry. The mediation arises due to an U(1) vector multiplet coupling to both a hidden supersymmetry breaking flux sector and a visible D-brane sector. The required internal manifolds can be constructed by non-Kaehler resolutions of singular Calabi-Yau manifolds. The effective action encoding the U(1) coupling is then determined in terms of the global topological properties of the internal space. We investigate suitable local geometries for the hidden and visible sector in detail. This includes a systematic study of orientifold symmetries of del Pezzo surfaces realized in compact geometries after geometric transition. We construct compact examples admitting the key properties to realize flux supersymmetry breaking and U(1) mediation. Their toric realization allows us to analyze the geometry of curve classes and confirm the topological connection between the hidden and visible sector. 7. Large eddy simulation of breaking waves DEFF Research Database (Denmark) Christensen, Erik Damgaard; Deigaard, Rolf 2001-01-01 A numerical model is used to simulate wave breaking, the large scale water motions and turbulence induced by the breaking process. The model consists of a free surface model using the surface markers method combined with a three-dimensional model that solves the flow equations. The turbulence....... The incoming waves are specified by a flux boundary condition. The waves are approaching in the shore-normal direction and are breaking on a plane, constant slope beach. The first few wave periods are simulated by a two-dimensional model in the vertical plane normal to the beach line. The model describes...... the steepening and the overturning of the wave. At a given instant, the model domain is extended to three dimensions, and the two-dimensional flow field develops spontaneously three-dimensional flow features with turbulent eddies. After a few wave periods, stationary (periodic) conditions are achieved... 8. Workshop on electroweak symmetry breaking: proceedings Energy Technology Data Exchange (ETDEWEB) Hinchliffe, I. (ed.) 1984-10-01 A theoretical workshop on electroweak symmetry breaking at the Superconducting Supercollider was held at Lawrence Berkeley Laboratory, June 4-22, 1984. The purpose of the workshop was to focus theoretical attention on the ways in which experimentation at the SSC could reveal manifestations of the phenomenon responsible for electroweak symmetry breaking. This issue represents, at present, the most compelling scientific argument for the need to explore the energy region to be made accessible by the SSC, and a major aim of the workshop was to involve a broad cross section of particle theorists in the ongoing process of sharpening the requirements for both accelerator and detector design that will ensure detection and identification of meaningful signals, whatever form the electroweak symmetry breaking phenomenon should actually take. Separate entries were prepared for the data base for the papers presented. 9. Workshop on electroweak symmetry breaking: proceedings International Nuclear Information System (INIS) Hinchliffe, I. 1984-10-01 A theoretical workshop on electroweak symmetry breaking at the Superconducting Supercollider was held at Lawrence Berkeley Laboratory, June 4-22, 1984. The purpose of the workshop was to focus theoretical attention on the ways in which experimentation at the SSC could reveal manifestations of the phenomenon responsible for electroweak symmetry breaking. This issue represents, at present, the most compelling scientific argument for the need to explore the energy region to be made accessible by the SSC, and a major aim of the workshop was to involve a broad cross section of particle theorists in the ongoing process of sharpening the requirements for both accelerator and detector design that will ensure detection and identification of meaningful signals, whatever form the electroweak symmetry breaking phenomenon should actually take. Separate entries were prepared for the data base for the papers presented 10. Breaking bad news in cancer patients. Science.gov (United States) Konstantis, Apostolos; Exiara, Triada 2015-01-01 In a regional hospital, many patients are newly diagnosed with cancer. Breaking the bad news in these patients and their relatives is a tough task. Many doctors are not experienced in talking to patients about death or death-related diseases. In recent years, there have been great efforts to change the current situation. The aim of this study was to investigate the experience and education of medical personnel in breaking bad news in a secondary hospital. 59 doctors from General Hospital of Komotini, Greece were included in the study. All the doctors were in clinical specialties that treated cancer patients. A brief questionnaire was developed based on current guidelines such as Baile/SPIKES framework and the ABCDE mnemonic. Residents are involved in delivering bad news less frequently than specialists. Only 21 doctors (35.59%) had specific training on breaking bad news. 20 doctors (33.90%) were aware of the available techniques and protocols on breaking bad news. 47 doctors (79.66%) had a consistent plan for breaking bad news. 57 (96.61%) delivered bad news in a quiet place, 53 (89.83%) ensured no interruptions and enough time, 53 (89.83%) used simple words and 54 (91.53%) checked for understanding and did not rush through the news. 46 doctors (77.97%) allowed relatives to determine patient's knowledge about the disease. There were low rates of specific training in breaking bad news. However, the selected location, the physician's speech and their plan were according to current guidelines. 11. Breaking bad news in cancer patients Directory of Open Access Journals (Sweden) Apostolos Konstantis 2015-01-01 Full Text Available Objective: In a regional hospital, many patients are newly diagnosed with cancer. Breaking the bad news in these patients and their relatives is a tough task. Many doctors are not experienced in talking to patients about death or death-related diseases. In recent years, there have been great efforts to change the current situation. The aim of this study was to investigate the experience and education of medical personnel in breaking bad news in a secondary hospital. Materials and Methods: 59 doctors from General Hospital of Komotini, Greece were included in the study. All the doctors were in clinical specialties that treated cancer patients. A brief questionnaire was developed based on current guidelines such as Baile/SPIKES framework and the ABCDE mnemonic. Results: Residents are involved in delivering bad news less frequently than specialists. Only 21 doctors (35.59% had specific training on breaking bad news. 20 doctors (33.90% were aware of the available techniques and protocols on breaking bad news. 47 doctors (79.66% had a consistent plan for breaking bad news. 57 (96.61% delivered bad news in a quiet place, 53 (89.83% ensured no interruptions and enough time, 53 (89.83% used simple words and 54 (91.53% checked for understanding and did not rush through the news. 46 doctors (77.97% allowed relatives to determine patient′s knowledge about the disease. Conclusions: There were low rates of specific training in breaking bad news. However, the selected location, the physician′s speech and their plan were according to current guidelines. 12. Theoretical predictions for alpha particle spectroscopic strengths International Nuclear Information System (INIS) Draayer, J.P. 1975-01-01 Multinucleon transfers induced in heavy-ion reactions of the type ( 6 Li,d) furnish a selective probe with which to study the interplay between rotational and clustering phenomena so characteristic of the structure of the light sd-shell nuclei. For these nuclei, theoretical predictions for inter-band as well as intra-band transfer strengths can be made using recently tabulated results for angular momentum dependent SU 3 inclusion R 3 relative spectroscopic strengths and angular momentum independent SU 6 inclusion SU 3 coefficients of fractional parentage. The pure SU 3 (oscillator)-SU 4 (supermultiplet) symmetry limit agrees well with results obtained using available eigenfunctions determined in large shell model calculations. In particular, the scalar nature of a transferred ''alpha''-cluster insures that the effect of spatial symmetry admixtures in the initial and final states of the target and residual nuclei are minimized. Sum rule quantities provide a measure of the probable effects of symmetry breaking. Strength variations within a band are expected; transfers to core excited states are often favored. Results extracted from exact finite range DWBA analyses of ( 6 Li,d) data on 16 , 18 O, 20 , 21 , 22 Ne, 24 , 25 Mg show some anomalies in our understanding of the structure and/or reaction mechanisms. (18 figures) (U.S.) 13. Implications of career break from personal and company perspectives OpenAIRE Vuorinen, Niina 2017-01-01 The objective of this study is to show the implications that career breaks have on individuals and employers. The intensions are to identify personal motivations for career breaks, and if the breaks change the careers of the people taking them. Furthermore, this study intends to understand how career breaks are viewed by employers, and if career breaks are becoming more acceptable internationally. The theoretical framework was based on description of work and careers both from employee an... 14. Coupled simulation of steam line break accident International Nuclear Information System (INIS) Royer, E.; Raimond, E.; Caruge, D. 2000-01-01 The steam line break is a PWR type reactor design accident, which concerns coupled physical phenomena. To control these problems simulation are needed to define and validate the operating procedures. The benchmark OECD PWR MSLB (Main Steam Line Break) has been proposed by the OECD to validate the feasibility and the contribution of the multi-dimensional tools in the simulation of the core transients. First the benchmark OECD PWR MSLB is presented. Then the analysis of the three exercises (system with pinpoint kinetic, three-dimensional core and whole system with three-dimensional core) are discussed. (A.L.B.) 15. The experimental investigation of supersymmetry breaking International Nuclear Information System (INIS) Peskin, M.E. 1996-04-01 If Nature is supersymmetric at the weak interaction scale, what can we hope to learn from experiments on supersymmetric particles? The most mysterious aspect of phenomenological supersymmetry is the mechanism of spontaneous supersymmetry breaking. This mechanism ties the observable pattern of supersymmetric particle masses to aspects of the underlying unified theory at very small distance scales. In this article, I will discuss a systematic experimental program to determine the mechanism of supersymmetry breaking. Both pp and e + e - colliders of the next generation play an essential role 16. What records have we been breaking? Science.gov (United States) Bartholow, J.M.; Milhous, R. 2002-01-01 "Today was another record-breaking day," the evening radio or television declares. High temperatures, low temperatures, floods, drought - take your choice. But how can we put these pronouncements in perspective? What do they really mean?We present two types of information in this article: 1) an analysis of daily air temperature and precipitation for Fort Collins and 2) an analysis of annual precipitation for Fort Collins. Each analysis provides a different meaning to the statement about a record-breaking day or year. 17. Detecting Structural Breaks using Hidden Markov Models DEFF Research Database (Denmark) Ntantamis, Christos Testing for structural breaks and identifying their location is essential for econometric modeling. In this paper, a Hidden Markov Model (HMM) approach is used in order to perform these tasks. Breaks are defined as the data points where the underlying Markov Chain switches from one state to another....... The estimation of the HMM is conducted using a variant of the Iterative Conditional Expectation-Generalized Mixture (ICE-GEMI) algorithm proposed by Delignon et al. (1997), that permits analysis of the conditional distributions of economic data and allows for different functional forms across regimes... 18. Chitosan fibers with improved biological and mechanical properties for tissue engineering applications. Science.gov (United States) Albanna, Mohammad Z; Bou-Akl, Therese H; Blowytsky, Oksana; Walters, Henry L; Matthew, Howard W T 2013-04-01 The low mechanical properties of hydrogel materials such as chitosan hinder their broad utility for tissue engineering applications. Previous research efforts improved the mechanical properties of chitosan fiber through chemical and physical modifications; however, unfavorable toxicity effects on cells were reported. In this paper, we report the preparation of chitosan fibers with improved mechanical and biocompatibility properties. The structure-property relationships of extruded chitosan fibers were explored by varying acetic acid (AA) concentration, ammonia concentration, annealing temperature and degree of heparin crosslinking. Results showed that optimizing AA concentration to 2vol% improved fiber strength and stiffness by 2-fold. Extruding chitosan solution into 25wt% of ammonia solution reduced fiber diameters and improved fiber strength by 2-fold and stiffness by 3-fold, due to an increase in crystallinity as confirmed by XRD. Fiber annealing further reduced fiber diameter and improved fiber strength and stiffness as temperature increased. Chitosan fibers crosslinked with heparin had increased diameter but lower strength and stiffness properties and higher breaking strain values. When individual parameters were combined, further improvement in fiber mechanical properties was achieved. All mechanically improved fibers and heparin crosslinked fibers promoted valvular interstitial cells (VIC) attachment and growth over 10 day cultures. Our results demonstrate the ability to substantially improve the mechanical properties of chitosan fibers without adversely affecting their biological properties. The investigated treatments offer numerous advantages over previous physical/chemical modifications and thus are expected to expand the utility of chitosan fibers with tunable mechanical properties in various tissue engineering applications. Copyright © 2012 Elsevier Ltd. All rights reserved. 19. Tissue Classification DEFF Research Database (Denmark) Van Leemput, Koen; Puonti, Oula 2015-01-01 Computational methods for automatically segmenting magnetic resonance images of the brain have seen tremendous advances in recent years. So-called tissue classification techniques, aimed at extracting the three main brain tissue classes (white matter, gray matter, and cerebrospinal fluid), are now...... well established. In their simplest form, these methods classify voxels independently based on their intensity alone, although much more sophisticated models are typically used in practice. This article aims to give an overview of often-used computational techniques for brain tissue classification... 20. Peaking cladding temperature and break equivalent size of intermediate break loss of coolant accident International Nuclear Information System (INIS) Luo Bangqi 2012-01-01 The analysis results of intermediate break loss of coolant accident for the nuclear power plant of million kw level showed to be as following: (1) At the begin of life, the break occur simultaneity reactor shutdown with L(X)P. it's equivalent break size and peaking cladding temperature is respectively 20 cm and 849℃. (2) At the begin of life, the break occur simultaneity reactor shutdown without loop. the reactor coolant pumps will be stop after reactor shutdown 10 minutes, it's equivalent break size and peaking cladding temperature is respectively 10.5 cm and 921℃. (3) At the bur up of 31 GWd/t(EOC1). the break occur simultaneity reactor shutdown without loop, the reactor coolant pumps will be stop after reactor shutdown 20 minutes, it's equivalent break size and peaking cladding temperature is respectively 8 cm and 1145℃. The above analysis results showed that the peaking cladding temperature of intermediate break loss of coolant accident is not only related with the break equivalent size and core bur up, and is closely related with the stop time of coolant pumps because the coolant pumps would drive the coolant from safety system to produce the seal loop in break loop and affect the core coolant flow, results in the fuel cladding temperature increasing or damaging. Therefore, the break spectrum, burn up spectrum, the stop time of coolant pumps and operator action time will need to detail analysis and provide appropriate operating procedure, otherwise the peaking cladding temperature will exceed 1204℃ and threaten the safety of the reactor core when the intermediate break loss of coolant accident occur in some break equivalent size, burn up, stop pumps time and operator action not appropriate. The pressurizer pressure low signal simultaneity containment pressure higher signal were used as the operator manual close the signal of reactor coolant pumps after reactor shutdown of 20 minutes. have successful solved the operator intervention time from 10 minutes 1. Shading Contributes to the Reduction of Stem Mechanical Strength by Decreasing Cell Wall Synthesis in Japonica Rice (Oryza sativa L. Directory of Open Access Journals (Sweden) Longmei Wu 2017-05-01 Full Text Available Low solar radiation caused by industrial development and solar dimming has become a limitation in crop production in China. It is widely accepted that low solar radiation influences many aspects of plant development, including slender, weak stems and susceptibility to lodging. However, the underlying mechanisms are not well understood. To clarify how low solar radiation affects stem mechanical strength formation and lodging resistance, the japonica rice cultivars Wuyunjing23 (lodging-resistant and W3668 (lodging-susceptible were grown under field conditions with normal light (Control and shading (the incident light was reduced by 60% with a black nylon net. The yield and yield components, plant morphological characteristics, the stem mechanical strength, cell wall components, culm microstructure, gene expression correlated with cellulose and lignin biosynthesis were measured. The results showed that shading significantly reduced grain yield attributed to reduction of spikelets per panicles and grain weight. The stem-breaking strength decreased significantly under shading treatment; consequently, resulting in higher lodging index in rice plant in both varieties, as revealed by decreased by culm diameter, culm wall thickness and increased plant height, gravity center height. Compared with control, cell wall components including non-structural carbohydrate, sucrose, cellulose, and lignin reduced quite higher. With histochemical straining, shading largely reduced lignin deposition in the sclerenchyma cells and vascular bundle cells compared with control, and decreased cellulose deposition in the parenchyma cells of culm tissue in both Wuyunjing23 and W3668. And under shading condition, gene expression involved in secondary cell wall synthesis, OsPAL, OsCOMT, OsCCoAOMT, OsCCR, and OsCAD2, and primary cell wall synthesis, OsCesA1, OsCesA3, and OsCesA8 were decreased significantly. These results suggest that gene expression involved in the reduction of 2. Shading Contributes to the Reduction of Stem Mechanical Strength by Decreasing Cell Wall Synthesis in Japonica Rice (Oryza sativa L.). Science.gov (United States) Wu, Longmei; Zhang, Wujun; Ding, Yanfeng; Zhang, Jianwei; Cambula, Elidio D; Weng, Fei; Liu, Zhenghui; Ding, Chengqiang; Tang, She; Chen, Lin; Wang, Shaohua; Li, Ganghua 2017-01-01 Low solar radiation caused by industrial development and solar dimming has become a limitation in crop production in China. It is widely accepted that low solar radiation influences many aspects of plant development, including slender, weak stems and susceptibility to lodging. However, the underlying mechanisms are not well understood. To clarify how low solar radiation affects stem mechanical strength formation and lodging resistance, the japonica rice cultivars Wuyunjing23 (lodging-resistant) and W3668 (lodging-susceptible) were grown under field conditions with normal light (Control) and shading (the incident light was reduced by 60%) with a black nylon net. The yield and yield components, plant morphological characteristics, the stem mechanical strength, cell wall components, culm microstructure, gene expression correlated with cellulose and lignin biosynthesis were measured. The results showed that shading significantly reduced grain yield attributed to reduction of spikelets per panicles and grain weight. The stem-breaking strength decreased significantly under shading treatment; consequently, resulting in higher lodging index in rice plant in both varieties, as revealed by decreased by culm diameter, culm wall thickness and increased plant height, gravity center height. Compared with control, cell wall components including non-structural carbohydrate, sucrose, cellulose, and lignin reduced quite higher. With histochemical straining, shading largely reduced lignin deposition in the sclerenchyma cells and vascular bundle cells compared with control, and decreased cellulose deposition in the parenchyma cells of culm tissue in both Wuyunjing23 and W3668. And under shading condition, gene expression involved in secondary cell wall synthesis, OsPAL, OsCOMT, OsCCoAOMT, OsCCR , and OsCAD2 , and primary cell wall synthesis, OsCesA1, OsCesA3 , and OsCesA8 were decreased significantly. These results suggest that gene expression involved in the reduction of lignin and 3. Strength of Fibrous Composites CERN Document Server Huang, Zheng-Ming 2012-01-01 "Strength of Fibrous Composites" addresses evaluation of the strength of a fibrous composite by using its constituent material properties and its fiber architecture parameters. Having gone through the book, a reader is able to predict the progressive failure behavior and ultimate strength of a fibrous laminate subjected to an arbitrary load condition in terms of the constituent fiber and matrix properties, as well as fiber geometric parameters. The book is useful to researchers and engineers working on design and analysis for composite materials. Dr. Zheng-Ming Huang is a professor at the School of Aerospace Engineering & Applied Mechanics, Tongji University, China. Mr. Ye-Xin Zhou is a PhD candidate at the Department of Mechanical Engineering, the University of Hong Kong, China. 4. High strength alloys Science.gov (United States) Maziasz, Phillip James [Oak Ridge, TN; Shingledecker, John Paul [Knoxville, TN; Santella, Michael Leonard [Knoxville, TN; Schneibel, Joachim Hugo [Knoxville, TN; Sikka, Vinod Kumar [Oak Ridge, TN; Vinegar, Harold J [Bellaire, TX; John, Randy Carl [Houston, TX; Kim, Dong Sub [Sugar Land, TX 2010-08-31 High strength metal alloys are described herein. At least one composition of a metal alloy includes chromium, nickel, copper, manganese, silicon, niobium, tungsten and iron. System, methods, and heaters that include the high strength metal alloys are described herein. At least one heater system may include a canister at least partially made from material containing at least one of the metal alloys. At least one system for heating a subterranean formation may include a tubular that is at least partially made from a material containing at least one of the metal alloys. 5. Hand grip strength DEFF Research Database (Denmark) Frederiksen, Henrik; Gaist, David; Petersen, Hans Christian 2002-01-01 in life is a major problem in terms of prevalence, morbidity, functional limitations, and quality of life. It is therefore of interest to find a phenotype reflecting physical functioning which has a relatively high heritability and which can be measured in large samples. Hand grip strength is known......-55%). A powerful design to detect genes associated with a phenotype is obtained using the extreme discordant and concordant sib pairs, of whom 28 and 77 dizygotic twin pairs, respectively, were found in this study. Hence grip strength is a suitable phenotype for identifying genetic variants of importance to mid... 6. Dynamical Symmetry Breaking in RN Quantum Gravity Directory of Open Access Journals (Sweden) A. T. Kotvytskiy 2011-01-01 Full Text Available We show that in the RN gravitation model, there is no dynamical symmetry breaking effect in the formalism of the Schwinger-Dyson equation (in flat background space-time. A general formula for the second variation of the gravitational action is obtained from the quantum corrections hμν (in arbitrary background metrics. 7. Numerical Simulation of a Seaway with Breaking Science.gov (United States) Dommermuth, Douglas; O'Shea, Thomas; Brucker, Kyle; Wyatt, Donald 2012-11-01 The focus of this presentation is to describe the recent efforts to simulate a fully non-linear seaway with breaking by using a high-order spectral (HOS) solution of the free-surface boundary value problem to drive a three-dimensional Volume of Fluid (VOF) solution. Historically, the two main types of simulations to simulate free-surface flows are the boundary integral equations method (BIEM) and high-order spectral (HOS) methods. BIEM calculations fail at the point at which the surface impacts upon itself, if not sooner, and HOS methods can only simulate a single valued free-surface. Both also employ a single-phase approximation in which the effects of the air on the water are neglected. Due to these limitations they are unable to simulate breaking waves and air entrainment. The Volume of Fluid (VOF) method on the other hand is suitable for modeling breaking waves and air entrainment. However it is computationally intractable to generate a realistic non-linear sea-state. Here, we use the HOS solution to quickly drive, or nudge, the VOF solution into a non-linear state. The computational strategies, mathematical formulation, and numerical implementation will be discussed. The results of the VOF simulation of a seaway with breaking will also be presented, and compared to the single phase, single valued HOS results. 8. Controlling break-the-glass through alignment NARCIS (Netherlands) Adriansyah, A.; Dongen, van B.F.; Zannone, N. 2013-01-01 Modern IT systems have to deal with unpredictable situations and exceptions more and more often. In contrast, security mechanisms are usually very rigid. This causes organizations to employ functionality like break-the-glass that allows users to bypass security mechanisms in case of emergencies. 9. The issue of supersymmetry breaking in strings International Nuclear Information System (INIS) Binetruy, P. 1989-12-01 We discuss the central role that supersymmetry plays in string models, both in spacetime and at the level of the string world-sheet. The problems associated with supersymmetry-breaking are reviewed together with some of the attempts to solve them, in the string as well as the field theory approach 10. Prediction of LOCA Break Size Using CFNN Energy Technology Data Exchange (ETDEWEB) Choi, Geon Pil; Yoo, Kwae Hwan; Back, Ju Hyun; Kim, Dong Yeong; Na, Man Gyun [Chosun University Gwangju (Korea, Republic of) 2016-05-15 The NPPs have the emergency core cooling system (ECCS) such as a safety injection system. The ECCS may not function properly in case of the small break size due to a slight change of pressure in the pipe. If the coolant is not supplied by ECCS, the reactor core will melt. Therefore, the meltdown of reactor core have to be prevented by appropriate accident management through the prediction of LOCA break size in advance. This study presents the prediction of LOCA break size using cascaded fuzzy neural network (CFNN). The CFNN model repeatedly applies FNN modules that are serially connected. The CFNN model is a data-based method that requires data for its development and verification. The data were obtained by numerically simulating severe accident scenarios of the optimized power reactor (OPR1000) using MAAP code, because real severe accident data cannot be obtained from actual NPP accidents. The CFNN model has been designed to rapidly predict the LOCA break size in LOCA situations. The CFNN model was trained by using the training data set and checked by using test data set. These data sets were obtained using MAAP code for OPR1000 reactor. The performance results of the CFNN model show that the RMS error decreases as the stage number of the CFNN model increases. In addition, the performance result of the CFNN model presents that the RMS error level is below 4%. 11. Lifshitz-sector mediated SUSY breaking International Nuclear Information System (INIS) Pospelov, Maxim; Tamarit, Carlos 2014-01-01 We propose a novel mechanism of SUSY breaking by coupling a Lorentz-invariant supersymmetric matter sector to non-supersymmetric gravitational interactions with Lifshitz scaling. The improved UV properties of Lifshitz propagators moderate the otherwise uncontrollable ultraviolet divergences induced by gravitational loops. This ensures that both the amount of induced Lorentz violation and SUSY breaking in the matter sector are controlled by Λ HL 2 /M P 2 , the ratio of the Hořava-Lifshitz cross-over scale Λ HL to the Planck scale M P . This ratio can be kept very small, providing a novel way of explicitly breaking supersymmetry without reintroducing fine-tuning. We illustrate our idea by considering a model of scalar gravity with Hořava-Lifshitz scaling coupled to a supersymmetric Wess-Zumino matter sector, in which we compute the two-loop SUSY breaking corrections to the masses of the light scalars due to the gravitational interactions and the heavy fields 12. Atmospheric noise of a breaking tidal bore. Science.gov (United States) Chanson, Hubert 2016-01-01 A tidal bore is a surge of waters propagating upstream in an estuary as the tidal flow turns to rising and the flood tide propagates into a funnel-shaped system. Large tidal bores have a marked breaking roller. The sounds generated by breaking tidal bores were herein investigated in the field (Qiantang River) and in laboratory. The sound pressure record showed two dominant periods, with some similarity with an earlier study [Chanson (2009). J. Acoust. Soc. Am. 125(6), 3561-3568]. The two distinct phases were the incoming tidal bore when the sound amplitude increased with the approaching bore, and the passage of the tidal bore in front of the microphone when loud and powerful noises were heard. The dominant frequency ranged from 57 to 131 Hz in the Qiantang River bore. A comparison between laboratory and prototype tidal bores illustrated both common features and differences. The low pitch sound of the breaking bore had a dominant frequency close to the collective oscillations of bubble clouds, which could be modeled with a bubble cloud model using a transverse dimension of the bore roller. The findings suggest that this model might be over simplistic in the case of a powerful breaking bore, like that of the Qiantang River. 13. Critical wind speed at which trees break Science.gov (United States) Virot, E.; Ponomarenko, A.; Dehandschoewercker, É.; Quéré, D.; Clanet, C. 2016-02-01 Data from storms suggest that the critical wind speed at which trees break is constant (≃42 m /s ), regardless of tree characteristics. We question the physical origin of this observation both experimentally and theoretically. By combining Hooke's law, Griffith's criterion, and tree allometry, we show that the critical wind speed indeed hardly depends on the height, diameter, and elastic properties of trees. 14. Spontaneous symmetry breaking in N = 2 supergravity International Nuclear Information System (INIS) Zinov'ev, Y.M. 1987-01-01 A model describing the interaction of N = 2 supergravity with a vector and a linear multiplet is constructed. The model admits the introduction of spontaneous supersymmetry breaking with two arbitrary scales, one of which can be equal to zero, corresponding to the partial super-Higgs effect (N = 2→N = 1). The cosmological term is automatically equal to zero 15. Firm break-up and performance Czech Academy of Sciences Publication Activity Database Kočenda, Evžen; Hanousek, Jan 2012-01-01 Roč. 13, č. 2 (2012), s. 121-143 ISSN 1435-6104 R&D Projects: GA ČR GA402/09/1595 Institutional support: PRVOUK-P23 Keywords : break-up of firms * corporate performance * ownership changes Subject RIV: AH - Economics Impact factor: 0.588, year: 2012 16. Pair breaking and charge relaxation in superconductors International Nuclear Information System (INIS) Nielson, J.B.; Pethick, C.J.; Rammer, J.; Smith, H. 1982-01-01 We present a general formalism based on the quasiclassical Green's function for calculating charge imbalance in nonequilibrium superconductors. Our discussion is sufficiently general that it applies at arbitrary temperatures, and under conditions when the width of quasiparticle states are appreciable due to pair breaking processes, and when strong coupling effects are significant. As a first application we demonstrate in detail how in the limit of smallpair breaking and for a weak coupling superconductor the collision term in the formalism reduces to the one in the quasiparticle Boltzmann equation. We next treat the case of charge imbalance generated by tunnel injection, with pair breaking by phonons and magnetic impurities. Over the range of temperatures investigated exerimentally to date, the calculated charge imbalance is rather close to that evaluated using the Boltzmann equation, even if pair braeking is so strong as almost to destroy superconductivity. Finally we consider charge imbalance generated by the combined influence of a supercurrent and a temperature gradient. We give calculations for a dirty superconductor with scattering by phonons as the pair breaking mechanism, and the results give a reasonable account of the experimental data of Clarke, Fjordboge, and Lindelof. We carry out calculations for the case of impurity scattering along which are valid not only in the clean and dirty limits, but also for intermediate situations. These enable us to see how the large contribution to the charge imbalance found for energies close to the gap edge in the clean case is reduced with increasing impurity scattering 17. Path-breaking books in regional science NARCIS (Netherlands) Waldorf, BS This article presents a collection of regional science books that long-standing members of the Regional Science Association International (RSAI) identified as path-breaking books. The most frequently nominated books include the "classics" by Isard, the seminal books in urban economics by Alonso, 18. Fragmentation in DNA double-strand breaks International Nuclear Information System (INIS) Wei Zhiyong; Suzhou Univ., Suzhou; Zhang Lihui; Li Ming; Fan Wo; Xu Yujie 2005-01-01 DNA double strand breaks are important lesions induced by irradiations. Random breakage model or quantification supported by this concept is suitable to analyze DNA double strand break data induced by low LET radiation, but deviation from random breakage model is more evident in high LET radiation data analysis. In this work we develop a new method, statistical fragmentation model, to analyze the fragmentation process of DNA double strand breaks. After charged particles enter the biological cell, they produce ionizations along their tracks, and transfer their energies to the cells and break the cellular DNA strands into fragments. The probable distribution of the fragments is obtained under the condition in which the entropy is maximum. Under the approximation E≅E 0 + E 1 l + E 2 l 2 , the distribution functions are obtained as exp(αl + βl 2 ). There are two components, the one proportional to exp(βl 2 ), mainly contributes to the low mass fragment yields, the other component, proportional to exp(αl), decreases slowly as the mass of the fragments increases. Numerical solution of the constraint equations provides parameters α and β. Experimental data, especially when the energy deposition is higher, support the statistical fragmentation model. (authors) 19. Critical wind speed at which trees break. Science.gov (United States) Virot, E; Ponomarenko, A; Dehandschoewercker, É; Quéré, D; Clanet, C 2016-02-01 Data from storms suggest that the critical wind speed at which trees break is constant (≃42m/s), regardless of tree characteristics. We question the physical origin of this observation both experimentally and theoretically. By combining Hooke's law, Griffith's criterion, and tree allometry, we show that the critical wind speed indeed hardly depends on the height, diameter, and elastic properties of trees. 20. SUSY breaking mediation by throat fields International Nuclear Information System (INIS) Bruemmer, F.; Hebecker, A.; Trapletti, M. 2006-01-01 We investigate, in the general framework of KKLT, the mediation of supersymmetry breaking by fields propagating in the strongly warped region of the compactification manifold ('throat fields'). Such fields can couple both to the supersymmetry breaking sector at the IR end of the throat and to the visible sector at the UV end. We model the supersymmetry breaking sector by a chiral superfield which develops an F term vacuum expectation value (also responsible for the uplift). It turns out that the mediation effect of vector multiplets propagating in the throat can compete with modulus-anomaly mediation. Moreover, such vector fields are naturally present as the gauge fields arising from isometries of the throat (most notably the SO(4) isometry of the Klebanov-Strassler solution). Their mediation effect is important in spite of their large 4d mass. The latter is due to the breaking of the throat isometry by the compact manifold at the UV end of the throat. The contribution from heavy chiral superfields is found to be subdominant 1. Symmetry breaking and restoration in gauge theories International Nuclear Information System (INIS) Natale, A.A. A review is made of the utilization of the Higgs mechanism in spontaneous symmetry breaking. It is shown that such as ideas came from an analogy with the superconductivity phenomenological theory based on a Ginzburg-Landau lagrangean. The symmetry restoration through the temperature influence is studied. (L.C.) [pt 2. Dynamical symmetry breaking in barium isotopes International Nuclear Information System (INIS) Rawat, Bir Singh; Chattopadhyay, P.K. 1997-01-01 The isotopes of Xe with mass numbers 124, 126, 128, 130 and the isotopes of barium with mass numbers 128, 130, 132, 134 were shown to correspond to the O(6) dynamical symmetry of IBM. In the investigation of the dynamical symmetry breaking in this region, the barium isotopes for departures from O(6) symmetry have been studied 3. Variations on supersymmetry breaking and neutrino spectra International Nuclear Information System (INIS) Borzumati, F.; Hamaguchi, K.; Nomura, Y.; Yanagida, T. 2000-01-01 The problem of generating light neutrinos within supersymmetric models is discussed. It is shown that the hierarchy of scales induced by supersymmetry breaking can give rise to suppression factors of the correct order of magnitude to produce experimentally allowed neutrino spectra 4. Unified gauge theories with spontaneous symmetry breaking International Nuclear Information System (INIS) MacDowell, S.W. 1975-01-01 Unified gauge theories with spontaneous symmetry breaking are studied with a view to renormalize quantum field theory. Georgi-Glashow and Weinberg-Salam models to unify weak and electromagnetic interactions are discussed in detail. Gauge theories of strong interactions are also considered [pt 5. Biochemical studies of DNA strand break repair and molecular characterization of mei-41, a gene involved in DNA break repair International Nuclear Information System (INIS) Oliveri, D.R. 1989-01-01 The ability to repair X-irradiation induced single-strand DNA breaks was examined in mutagen-sensitive mutants of Drosophila melanogaster. This analysis demonstrated that examined stocks possess a normal capacity to repair X-ray induced single-strand breaks. One of the mutants in this study, mei-41, has been shown to be involved in a number of DNA metabolizing functions. A molecular characterization of this mutant is presented. A cDNA hybridizing to genomic DNA both proximal and distal to a P element inducing a mei-41 mutation was isolated from both embryonic and adult female recombinant lambda phage libraries. A 2.2 kilobase embryonic cDNA clone was sequenced; the sequence of an open reading frame was identified which would predict a protein of 384 amino acids with a molecular weight of 43,132 daltons. An examination of homologies to sequences in protein and nucleic acid data bases revealed no sequences with significant homology to mei-41, however, two potential Zinc-finger domains were identified. Analysis of RNA hybridizing to the embryonic cDNA demonstrated the existence of a major 2.2 kilobase transcript expressed primarily in embryos and adult flies. An examination of the transcription of this gene in mei-41 mutants revealed significant variation from wild-type, an indication that the embryonic cDNA does represent a mei-41 transcript. Expression in tissues from adult animals demonstrated that the 2.2 kilobase RNA is expressed primarily in reproductive tissues. A 3.8kb transcript is the major species of RNA in the adult head and thorax. Evidence is presented which implies that expression of the mei-41 gene is strongly induced by exposure of certain cells to mutagens 6. OPTIMUM DESIGN OF ULTRAHIGH STRENGTH NANOLAYERED COMPOSITES Energy Technology Data Exchange (ETDEWEB) H. KUNG; ET AL 2000-10-01 This is the final report of a three-year, Laboratory Directed Research and Development (LDRD) project at Los Alamos National Laboratory (LANL). Refinement of the microstructure in metallic multilayers from the micrometer-scale to the nanometer-scale often results in a break down of the classical Hall-Petch model relating strength to the microstructural length scale. The critical length scale at which this behavior breaks down is investigated both experimentally and theoretically. Using transmission electron microscopy and nanoindentation, we evaluated the microstructure and mechanical properties of Cu/Cr, Cu./Ni, and Cu/Nb multilayers that had different shear moduli mismatch between layers and lattice misfit strain between layers. Two-dimensional maps showing layer thickness and grain size ranges over which different deformation mechanisms operate were constructed using dislocation theory. The deformation mechanisms responsible for the breakdown of Hall-Petch behavior are discussed. By correlating the deformation mechanism maps with the experimental data, we show that these maps serve as guidelines for interpreting the scale-dependent deformation mechanisms in multilayers. Atomistic simulation was also used to evaluate the interaction between interfaces and glide dislocations to provide atomic scale insights into the deformation mechanisms. 7. Probe tests microweld strength Science.gov (United States) 1965-01-01 Probe is developed to test strength of soldered, brazed or microwelded joints. It consists of a spring which may be adjusted to the desired test pressure by means of a threaded probe head, and an indicator lamp. Device may be used for electronic equipment testing. 8. Musculoskeletal injuries in break-dancers. Science.gov (United States) Cho, Chul Hyun; Song, Kwang Soon; Min, Byung Woo; Lee, Sung Moon; Chang, Hyuk Won; Eum, Dae Seup 2009-11-01 Since no epidemiologic studies have been reported about musculoskeletal injuries in break-dancers, there are no data on the rates and patterns of musculoskeletal injuries in this population that clinicians can use to find ways to decrease injury rate. We believe that the incidence of injuries in break-dancers is higher than assumed and that injury rates and patterns differ between professional and amateur dancers. Descriptive epidemiologic study. Of a total of 42 study subjects, 23 were professional dancers and 19 were amateur dancers. Injury frequency, site and type, along with the presence of supervised training, the use of protective devices and warm-up exercises done were recorded. Of the 42 study subjects, excluding two amateur dancers, 40 (95.2%) had had musculoskeletal injuries at more than one site. The mean number of sites per dancer was 4.60. The frequency of injury depended on the site and was as follows: wrist (69.0%), finger (61.9%), knee (61.9%), shoulder (52.4%), lumbar spine (50.0%), elbow (42.9%), cervical spine (38.1%), ankle (38.1%), foot (28.6%) and hip (16.7%). Sprain, strain and tendinitis were the most common injuries, accounting for the most cases. Of the 42 dancers, 13 (31%) had had fractures or dislocations. Eight (19.1%) learned break-dancing under supervised instruction, 17 (40.5%) used protective devices and 28 (66.7%) performed warm-up exercises before dancing. There were significant differences in age, dance career length, amount of dance training, mean number of injury sites and the presence of supervised training between professionals and amateurs (Pnature of the activities that result in both unusual and common injuries in break-dancers and educate them about safety. Careful screening, instruction and supervised training of break-dancers will help to prevent injuries. 9. Breaking bad news among cancer physicians Directory of Open Access Journals (Sweden) Sami Ayed Alshammary 2017-01-01 Full Text Available Background: Breaking bad news to patients with cancer diagnosis is not an easy task for physicians. The diagnosis must be explicitly stated and understood, and prognosis must be well-discussed in the most gentle and comfortable manner. It is important that the disclosure is performed in a way that patients will not lose all hope and get very depressed, leading them to undergo an abrupt change of their outlook in life. Objective: The aim of this study was to explore the physicians' perceptions and perspectives of breaking bad news to cancer patients. Methods: A cross-sectional survey of all comprehensive cancer centre physicians currently working in a university teaching hospital in the Middle East was conducted from August to September 2016. Results: Sixty-eight percent responded to the survey. Eighty-four percent were comfortable with breaking bad news, and 70% had training in breaking bad news. Eighty-six percent of responders stated that patients should be told about their cancer. Almost 30% of the respondents stated that they would still disclose the diagnosis to patients even if it would be against the preference of the relatives. Nearly 61% said that they would only tell the details to the patients if asked while 67% of them disagreed that patients should be told about the diagnoses only if the relatives consent. About 51% of physicians wanted to discuss the bad news with the family members and patient together, whereas 24% stated that the patient alone should be involved in the discussion. Conclusion: Physicians face a dilemma when families do not wish the patient to know the cancer diagnosis and this highlights the necessity of taking into consideration the social circumstances in healthcare. When taking these into considerations, curriculum in the medical school must, therefore, be updated and must integrate the acquisition of skills in breaking bad news early in training. 10. Quantum break-time of de Sitter Energy Technology Data Exchange (ETDEWEB) Dvali, Gia; Gómez, César; Zell, Sebastian, E-mail: georgi.dvali@physik.uni-muenchen.de, E-mail: cesar.gomez@uam.es, E-mail: sebastian.zell@campus.lmu.de [Arnold Sommerfeld Center, Ludwig-Maximilians-Universität, Theresienstraße 37, 80333 München (Germany) 2017-06-01 The quantum break-time of a system is the time-scale after which its true quantum evolution departs from the classical mean field evolution. For capturing it, a quantum resolution of the classical background—e.g., in terms of a coherent state—is required. In this paper, we first consider a simple scalar model with anharmonic oscillations and derive its quantum break-time. Next, following [1], we apply these ideas to de Sitter space. We formulate a simple model of a spin-2 field, which for some time reproduces the de Sitter metric and simultaneously allows for its well-defined representation as quantum coherent state of gravitons. The mean occupation number N of background gravitons turns out to be equal to the de Sitter horizon area in Planck units, while their frequency is given by the de Sitter Hubble parameter. In the semi-classical limit, we show that the model reproduces all the known properties of de Sitter, such as the redshift of probe particles and thermal Gibbons-Hawking radiation, all in the language of quantum S -matrix scatterings and decays of coherent state gravitons. Most importantly, this framework allows to capture the 1/ N -effects to which the usual semi-classical treatment is blind. They violate the de Sitter symmetry and lead to a finite quantum break-time of the de Sitter state equal to the de Sitter radius times N . We also point out that the quantum-break time is inversely proportional to the number of particle species in the theory. Thus, the quantum break-time imposes the following consistency condition: older and species-richer universes must have smaller cosmological constants. For the maximal, phenomenologically acceptable number of species, the observed cosmological constant would saturate this bound if our Universe were 10{sup 100} years old in its entire classical history. 11. Quantum break-time of de Sitter Science.gov (United States) Dvali, Gia; Gómez, César; Zell, Sebastian 2017-06-01 The quantum break-time of a system is the time-scale after which its true quantum evolution departs from the classical mean field evolution. For capturing it, a quantum resolution of the classical background—e.g., in terms of a coherent state—is required. In this paper, we first consider a simple scalar model with anharmonic oscillations and derive its quantum break-time. Next, following [1], we apply these ideas to de Sitter space. We formulate a simple model of a spin-2 field, which for some time reproduces the de Sitter metric and simultaneously allows for its well-defined representation as quantum coherent state of gravitons. The mean occupation number N of background gravitons turns out to be equal to the de Sitter horizon area in Planck units, while their frequency is given by the de Sitter Hubble parameter. In the semi-classical limit, we show that the model reproduces all the known properties of de Sitter, such as the redshift of probe particles and thermal Gibbons-Hawking radiation, all in the language of quantum S-matrix scatterings and decays of coherent state gravitons. Most importantly, this framework allows to capture the 1/N-effects to which the usual semi-classical treatment is blind. They violate the de Sitter symmetry and lead to a finite quantum break-time of the de Sitter state equal to the de Sitter radius times N. We also point out that the quantum-break time is inversely proportional to the number of particle species in the theory. Thus, the quantum break-time imposes the following consistency condition: older and species-richer universes must have smaller cosmological constants. For the maximal, phenomenologically acceptable number of species, the observed cosmological constant would saturate this bound if our Universe were 10100 years old in its entire classical history. 12. Reliability, Validity, and Sensitivity of a Novel Smartphone-Based Eccentric Hamstring Strength Test in Professional Football Players. Science.gov (United States) Lee, Justin W Y; Cai, Ming-Jing; Yung, Patrick S H; Chan, Kai-Ming 2018-05-01 To evaluate the test-retest reliability, sensitivity, and concurrent validity of a smartphone-based method for assessing eccentric hamstring strength among male professional football players. A total of 25 healthy male professional football players performed the Chinese University of Hong Kong (CUHK) Nordic break-point test, hamstring fatigue protocol, and isokinetic hamstring strength test. The CUHK Nordic break-point test is based on a Nordic hamstring exercise. The Nordic break-point angle was defined as the maximum point where the participant could no longer support the weight of his body against gravity. The criterion for the sensitivity test was the presprinting and postsprinting difference of the Nordic break-point angle with a hamstring fatigue protocol. The hamstring fatigue protocol consists of 12 repetitions of the 30-m sprint with 30-s recoveries between sprints. Hamstring peak torque of the isokinetic hamstring strength test was used as the criterion for validity. A high test-retest reliability (intraclass correlation coefficient = .94; 95% confidence interval, .82-.98) was found in the Nordic break-point angle measurements. The Nordic break-point angle significantly correlated with isokinetic hamstring peak torques at eccentric action of 30°/s (r = .88, r 2 = .77, P hamstring strength measures among male professional football players. 13. Photothermal effects of laser tissue soldering International Nuclear Information System (INIS) McNally, K.M.; Sorg, B.S.; Welch, A.J.; Dawes, J.M.; Owen, E.R. 1999-01-01 Low-strength anastomoses and thermal damage of tissue are major concerns in laser tissue welding techniques where laser energy is used to induce thermal changes in the molecular structure of the tissues being joined, hence allowing them to bond together. Laser tissue soldering, on the other hand, is a bonding technique in which a protein solder is applied to the tissue surfaces to be joined, and laser energy is used to bond the solder to the tissue surfaces. The addition of protein solders to augment tissue repair procedures significantly reduces the problems of low strength and thermal damage associated with laser tissue welding techniques. Investigations were conducted to determine optimal solder and laser parameters for tissue repair in terms of tensile strength, temperature rise and damage and the microscopic nature of the bonds formed. An in vitro study was performed using an 808 nm diode laser in conjunction with indocyanine green (ICG)-doped albumin protein solders to repair bovine aorta specimens. Liquid and solid protein solders prepared from 25% and 60% bovine serum albumin (BSA), respectively, were compared. The efficacy of temperature feedback control in enhancing the soldering process was also investigated. Increasing the BSA concentration from 25% to 60% greatly increased the tensile strength of the repairs. A reduction in dye concentration from 2.5mgml -1 to 0.25mgml -1 was also found to result in an increase in tensile strength. Increasing the laser irradiance and thus surface temperature resulted in an increased severity of histological injury. Thermal denaturation of tissue collagen and necrosis of the intimal layer smooth muscle cells increased laterally and in depth with higher temperatures. The strongest repairs were produced with an irradiance of 6.4Wcm -2 using a solid protein solder composed of 60% BSA and 0.25mgml -1 ICG. Using this combination of laser and solder parameters, surface temperatures were observed to reach 85±5 deg. C with a 14. B-L mediated SUSY breaking with radiative B-L symmetry breaking International Nuclear Information System (INIS) Kikuchi, Tatsuru; Kubo, Takayuki 2008-01-01 We explore a mechanism of radiative B-L symmetry breaking in analogous to the radiative electroweak symmetry breaking. The breaking scale of B-L symmetry is related to the neutrino masses through the see-saw mechanism. Once we incorporate the U(1) B-L gauge symmetry in SUSY models, the U(1) B-L gaugino, Z-tilde B-L appears, and it can mediate the SUSY breaking (Z-prime mediated SUSY breaking) at around the scale of 10 6 GeV. Then we find a links between the neutrino mass (more precisly the see-saw or B-L scale of order 10 6 GeV) and the Z-prime mediated SUSY breaking scale. It is also very interesting that the gluino at the weak scale becomes relatively light, and almost compressed mass spectra for the gaugino sector can be realized in this scenario, which is very interesting in scope of the LHC. 15. Redox Buffer Strength Science.gov (United States) de Levie, Robert 1999-04-01 The proper functioning of enzymes in bodily fluids requires that the pH be maintained within rather narrow limits. The first line of defense against large pH fluctuations in such fluids is the passive control provided by the presence of pH buffers. The ability of pH buffers to stabilize the pH is indicated by the buffer value b introduced in 1922 by van Slyke. It is equally important for many enzymes that the redox potential is kept within a narrow range. In that case, stability of the potential is most readily achieved with a redox buffer. In this communication we define the redox buffer strength by analogy with acid-base buffer strength. 16. More efficient repair of DNA double-strand breaks in skeletal muscle stem cells compared to their committed progeny OpenAIRE Leyla Vahidi Ferdousi; Pierre Rocheteau; Romain Chayot; Benjamin Montagne; Zayna Chaker; Patricia Flamant; Shahragim Tajbakhsh; Miria Ricchetti 2014-01-01 International audience; The loss of genome integrity in adult stem cells results in accelerated tissue aging and is possibly cancerogenic. Adult stem cells in different tissues appear to react robustly to DNA damage. We report that adult skeletal stem (satellite) cells do not primarily respond to radiation-induced DNA double-strand breaks (DSBs) via differentiation and exhibit less apoptosis compared to other myogenic cells. Satellite cells repair these DNA lesions more efficiently than their... 17. Corium crust strength measurements Energy Technology Data Exchange (ETDEWEB) Lomperski, S. [Argonne National Laboratory, 9700 S. Cass Avenue, Argonne, IL 60439-4840 (United States)], E-mail: lomperski@anl.gov; Farmer, M.T. [Argonne National Laboratory, 9700 S. Cass Avenue, Argonne, IL 60439-4840 (United States)], E-mail: farmer@anl.gov 2009-11-15 Corium strength is of interest in the context of a severe reactor accident in which molten core material melts through the reactor vessel and collects on the containment basemat. Some accident management strategies involve pouring water over the melt to solidify it and halt corium/concrete interactions. The effectiveness of this method could be influenced by the strength of the corium crust at the interface between the melt and coolant. A strong, coherent crust anchored to the containment walls could allow the yet-molten corium to fall away from the crust as it erodes the basemat, thereby thermally decoupling the melt from the coolant and sharply reducing the cooling rate. This paper presents a diverse collection of measurements of the mechanical strength of corium. The data is based on load tests of corium samples in three different contexts: (1) small blocks cut from the debris of the large-scale MACE experiments, (2) 30 cm-diameter, 75 kg ingots produced by SSWICS quench tests, and (3) high temperature crusts loaded during large-scale corium/concrete interaction (CCI) tests. In every case the corium consisted of varying proportions of UO{sub 2}, ZrO{sub 2}, and the constituents of concrete to represent a LWR melt at different stages of a molten core/concrete interaction. The collection of data was used to assess the strength and stability of an anchored, plant-scale crust. The results indicate that such a crust is likely to be too weak to support itself above the melt. It is therefore improbable that an anchored crust configuration could persist and the melt become thermally decoupled from the water layer to restrict cooling and prolong an attack of the reactor cavity concrete. 18. Strength capability while kneeling. Science.gov (United States) Haslegrave, C M; Tracy, M F; Corlett, E N 1997-12-01 Work sometimes has to be carried out kneeling, particularly where jobs are performed in confined spaces as is common for miners, aircraft baggage handlers and maintenance workers. In order to assess the risks in performing forceful tasks under such conditions, data is needed on strength capabilities of kneeling subjects. A study was undertaken to measure isometric strength in single-handed exertions for male subjects and to investigate the effects on this of task layout factors (direction of force exertion, reach distance, height of the workpiece and orientation relative to the subject's sagittal plane). The data has been tabulated to show the degree to which strength may be reduced in different situations and analysis of the task factors showed their influence to be complex with direction of exertion and reach distance having the greatest effect. The results also suggest that exertions are weaker when subjects are kneeling on two knees than when kneeling on one knee, although this needs to be confirmed by direct experimental comparison. 19. Dual realizations of dynamical symmetry breaking International Nuclear Information System (INIS) Dudas, Emilian; Papineau, Chloe 2006-01-01 We show the infrared equivalence between a recently proposed model containing a six dimensional scalar field with a four-dimensional localized Higgs type potential and the four-dimensional Nambu-Jona-Lasinio (NJL) model. In the dual NJL description, the fermions are localized at the origin of a large two-dimensional compact space. Due to a classical running effect above the compactification scale, the four-fermion coupling of the NJL model increases from the cutoff scale down to the compactification scale, providing the large Fermi coupling needed for the dynamical symmetry breaking. We also present a string theory embedding of our field-theory construction. On more general grounds, our results suggest that 4d models with dynamical symmetry breaking can be given a higher dimensional description in terms of field theories with nontrivial boundary conditions in the internal space 20. Boost breaking in the EFT of inflation Energy Technology Data Exchange (ETDEWEB) Delacrétaz, Luca V.; Senatore, Leonardo [Stanford Institute for Theoretical Physics, Stanford University, Stanford, CA 94305 (United States); Noumi, Toshifumi, E-mail: lvd@stanford.edu, E-mail: tnoumi@phys.sci.kobe-u.ac.jp, E-mail: senatore@stanford.edu [Jockey Club Institute for Advanced Study, Hong Kong University of Science and Technology (Hong Kong) 2017-02-01 If time-translations are spontaneously broken, so are boosts. This symmetry breaking pattern can be non-linearly realized by either just the Goldstone boson of time translations, or by four Goldstone bosons associated with time translations and boosts. In this paper we extend the Effective Field Theory of Multifield Inflation to consider the case in which the additional Goldstone bosons associated with boosts are light and coupled to the Goldstone boson of time translations. The symmetry breaking pattern forces a coupling to curvature so that the mass of the additional Goldstone bosons is predicted to be equal to √2 H in the vast majority of the parameter space where they are light. This pattern therefore offers a natural way of generating self-interacting particles with Hubble mass during inflation. After constructing the general effective Lagrangian, we study how these particles mix and interact with the curvature fluctuations, generating potentially detectable non-Gaussian signals. 1. Analysis of chiral symmetry breaking mechanism International Nuclear Information System (INIS) Guo, X. H.; Academia Sinica, Beijing; Huang, T.; CCAST 1997-01-01 The renormalization group invariant quark condensate μ is determined both from the consistent equation for quark condensate in the chiral limit and from the Schwinger-Dyson (SD) equation improved by the intermediate range QCD force singular like δ (q) which is associated with the gluon condensate. The solutions of μ in these two equations are consistent. The authors also obtain the critical strong coupling constant α c above which chiral symmetry breaks in these two approaches. The nonperturbative kernel of the SD equation makes α c smaller and μ bigger. An intuitive picture of the condensation above α c is discussed. In addition, with the help of the Slavnov-Taylor-Ward (STW) identity they derive the equations for the nonperturbative quark propagator from the SD equation in the presence of the intermediate range force and find that the intermediate-range force is also responsible for dynamical chiral symmetry breaking 2. [Breaking bad news in clinical practice]. Science.gov (United States) Herrera, Andrea; Ríos, Matías; Manríquez, José Manuel; Rojas, Gonzalo 2014-10-01 Breaking bad news is a complex task that requires multiple communication skills from health professionals. Clinical practice demands to communicate all type of bad news, from a diagnosis of cancer to adverse effects of a treatment. On the other hand, since the beginning of the health reform in 2003, the need to improve the quality of services was proposed, among which the concern about the rights and duties of patients stands out. Therefore, the health care provider-patient relationship becomes again the subject of discussion and study, and a topic of great importance for clinical work. We revise the consequences of breaking bad news for the patient and for the health care provider, as well as the current protocols available for this purpose. The importance of developing communication skills both for future health professionals as for those who currently work in the area is emphasized. 3. Fractional Branes and Dynamical Supersymmetry Breaking CERN Document Server Franco, S; Saad, F; Uranga, Angel M; Franco, Sebastian; Hanany, Amihay; Saad, Fouad; Uranga, Angel M. 2006-01-01 We study the dynamics of fractional branes at toric singularities, including cones over del Pezzo surfaces and the recently constructed Y^{p,q} theories. We find that generically the field theories on such fractional branes show dynamical supersymmetry breaking, due to the appearance of non-perturbative superpotentials. In special cases, one recovers the known cases of supersymmetric infrared behaviors, associated to SYM confinement (mapped to complex deformations of the dual geometries, in the gauge/string correspondence sense) or N=2 fractional branes. In the supersymmetry breaking cases, when the dynamics of closed string moduli at the singularity is included, the theories show a runaway behavior (involving moduli such as FI terms or equivalently dibaryonic operators), rather than stable non-supersymmetric minima. We comment on the implications of this gauge theory behavior for the infrared smoothing of the dual warped throat solutions with 3-form fluxes, describing duality cascades ending in such field th... 4. A break in the obesity epidemic? DEFF Research Database (Denmark) Visscher, T L S; Heitmann, B L; Rissanen, A 2015-01-01 Recent epidemiologic papers are presenting prevalence data suggesting breaks and decreases in obesity rates. However, before concluding that the obesity epidemic is not increasing anymore, the validity of the presented data should be discussed more thoroughly. We had a closer look into the litera......, focusing on trends in waist circumference rather than BMI leads to a less optimistic conclusion: the public health problem of obesity is still increasing.International Journal of Obesity advance online publication, 22 July 2014; doi:10.1038/ijo.2014.98....... into the literature presented in recent reviews to address the major potential biases and distortions, and to develop insights about how to interpret the presented suggestions for a potential break in the obesity epidemic. Decreasing participation rates, the use of reported rather than measured data and small sample... 5. Selecting a model of supersymmetry breaking mediation International Nuclear Information System (INIS) AbdusSalam, S. S.; Allanach, B. C.; Dolan, M. J.; Feroz, F.; Hobson, M. P. 2009-01-01 We study the problem of selecting between different mechanisms of supersymmetry breaking in the minimal supersymmetric standard model using current data. We evaluate the Bayesian evidence of four supersymmetry breaking scenarios: mSUGRA, mGMSB, mAMSB, and moduli mediation. The results show a strong dependence on the dark matter assumption. Using the inferred cosmological relic density as an upper bound, minimal anomaly mediation is at least moderately favored over the CMSSM. Our fits also indicate that evidence for a positive sign of the μ parameter is moderate at best. We present constraints on the anomaly and gauge mediated parameter spaces and some previously unexplored aspects of the dark matter phenomenology of the moduli mediation scenario. We use sparticle searches, indirect observables and dark matter observables in the global fit and quantify robustness with respect to prior choice. We quantify how much information is contained within each constraint. 6. Soft supersymmetry breaking in KKLT flux compactification International Nuclear Information System (INIS) Choi, K.; Falkowski, A.; Nilles, H.P.; Olechowski, M. 2005-01-01 We examine the structure of soft supersymmetry breaking terms in KKLT models of flux compactification with low energy supersymmetry. Moduli are stabilized by fluxes and nonperturbative dynamics while a de Sitter vacuum is obtained by adding supersymmetry breaking anti-branes. We discuss the characteristic pattern of mass scales in such a set-up as well as some features of 4D N=1 supergravity breakdown by anti-branes. Anomaly mediation is found to always give an important contribution and one can easily arrange for flavor-independent soft terms. In its most attractive realization, the modulus mediation is comparable to the anomaly mediation, yielding a quite distinctive sparticle spectrum. In addition, the axion component of the modulus/dilaton superfield dynamically cancels the relative CP phase between the contributions of anomaly and modulus mediation, thereby avoiding dangerous SUSY CP violation 7. Qinshan NPP large break LOCA safety analysis International Nuclear Information System (INIS) Shi Guobao; Tang Jiahuan; Zhou Quanfu; Wang Yangding 1997-01-01 Qinshan NPP is the first nuclear power plant in the mainland of China, a 300 MW(e) two-loop PWR. Large break LOCA is the design-basis accident of Qinshan NPP. Based on available computer codes, the own analysis method which complies with Appendix k of 10 CFR 50 has been established. The RELAP4/MOD7 code is employed for the calculations of blowdown, refill and reflood phase of the RCS respectively. The CONTEMPT-LT/028 code is used for the containment pressure and temperature analysis. The temperature transient in the hot rod is calculated using the FRAP-6T code. Conservative initial and functional assumptions were adopted during Qinshan NPP large break LOCA analysis. The results of the analysis show the applicable acceptance criteria for the loss-of-coolant accident are met 8. Isospin breaking in octet baryon mass splittings Energy Technology Data Exchange (ETDEWEB) Horsley, R. [Edinburgh Univ. (United Kingdom). School of Physics and Astronomy; Najjar, J. [Regensburg Univ. (Germany). Institut fuer Theoretische Physik; Nakamura, Y. [RIKEN Advanced Institute for Computational Science, Kobe, Hyogo (Japan); Pleiter, D. [Forschungszentrum Juelich (Germany). Juelich Supercomputer Centre; Rakow, P.E.L. [Liverpool Univ. (United Kingdom). Theoretical Physics Division; Schierholz, G. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Zanotti, J.M. [Adelaide Univ., SA (Australia). CSSM, School of Chemistry and Physics 2012-06-15 Using an SU(3) flavour symmetry breaking expansion in the quark mass, we determine the QCD component of the nucleon, Sigma and Xi mass splittings of the baryon octet due to up-down (and strange) quark mass differences in terms of the kaon mass splitting. Provided the average quark mass is kept constant, the expansion coefficients in our procedure can be determined from computationally cheaper simulations with mass degenerate sea quarks and partially quenched valence quarks. Both the linear and quadratic terms in the SU(3) flavour symmetry breaking expansion are considered; it is found that the quadratic terms only change the result by a few percent, indicating that the expansion is highly convergent. 9. Electroweak symmetry breaking: Higgs/whatever International Nuclear Information System (INIS) Chanowitz, M.S. 1989-01-01 In the first of these two lectures the Higgs mechanism is reviewed in its most general form, which does not necessarily require the existence of Higgs bosons. The general consequences of the hypothesis that electroweak symmetry breaking is due to the Higgs mechanism are deduced just from gauge invariance and unitarity. In the second lecture the general properties are illustrated with three specific models: the Weinberg-Salam model, its minimal supersymmetric extension, and technicolor. The second lecture concludes with a discussion of the experiment signals for strong WW scattering, whose presence or absence will allow us to determine whether the symmetry breaking sector lies above or below 1 TeV. 57 refs 10. Dynamics of Symmetry Breaking and Tachyonic Preheating CERN Document Server Felder, G; Greene, P B; Kofman, L A; Linde, Andrei D; Tkachev, Igor I; Felder, Gary; Garcia-Bellido, Juan; Greene, Patrick B.; Kofman, Lev; Linde, Andrei; Tkachev, Igor 2001-01-01 We reconsider the old problem of the dynamics of spontaneous symmetry breaking using 3d lattice simulations, and develop a theory of tachyonic preheating, which occurs due to the spinodal instability of the scalar field. Tachyonic preheating is so efficient that symmetry breaking typically completes within a single oscillation of the field distribution as it rolls towards the minimum of its effective potential. As an application of this theory we consider preheating in the hybrid inflation scenario, including SUSY-motivated F-term and D-term inflationary models. We show that preheating in hybrid inflation is typically tachyonic and the stage of oscillations of a homogeneous component of the scalar fields driving inflation ends after a single oscillation. Our results may also be relevant for the theory of the formation of disoriented chiral condensates in heavy ion collisions. 11. Automatic first-break picking using the instantaneous traveltime attribute KAUST Repository Saragiotis, Christos; Alkhalifah, Tariq Ali 2012-01-01 Picking the first breaks is an important step in seismic processing. The large volume of the seismic data calls for automatic and objective picking. We introduce a new automatic first-break picker, which uses specifically designed time windows 12. On the character of scale symmetry breaking in gauge theories International Nuclear Information System (INIS) Gusijnin, V.P.; Kushnir, V.A.; Miransky, V.A. 1988-01-01 The problem of scale symmetry breaking in gauge theories is discussed. It is shown that the phenomenon of spontaneous breaking of scale symmetry in gauge theories is incompatible with the PCAAC dynamics. 12 refs 13. Microwave-assisted rock breaking modelling and application CSIR Research Space (South Africa) Monchusi, B 2012-10-01 Full Text Available As part of the ongoing development of novel mining methods, the CSIR has developed alternative methods to break rocks. In this case, we show the application of microwave energy to break narrow tabular ore bodies.... 14. Break-even analysis in a nurse-managed center. Science.gov (United States) McBryde-Foster, Merry J 2005-01-01 The concept of break-even analysis as a financial assessment tool is defined and demonstrated in evaluation of a proposed nurse-managed center. The advantages of using break-even analysis during proposal development are explored. 15. Breaking Bad Habits | NIH MedlinePlus the Magazine Science.gov (United States) ... of this page please turn Javascript on. Feature: Bad Habits Breaking Bad Habits: Why It's So Hard to Change Past Issues / ... News in Health ( http://newsinhealth.nih.gov/ ) Break Bad Habits Avoid temptations. If you always stop for a ... 16. Breaking democracy with non renormalizable mass terms CERN Document Server Silva-Marcos, Joaquim I 2001-01-01 The exact democratic structure for the quark mass matrix, resulting from the action of the family symmetry groupA_{3L}\\times A_{3R}$, is broken by the vacuum expectation values of heavy singlet fields appearing in non renormalizable dimension 6 operators. Within this specific context of breaking of the family symmetry we formulate a very simple ansatz which leads to correct quark masses and mixings. 17. Charge-independence-breaking in the triton International Nuclear Information System (INIS) Gloeckle, W.; Lee, T.S.H.; Wiringa, R.B. 1990-01-01 We find the effect of the observed charge-independence-breaking in 1 S 0 nucleon-nucleon scattering on the binding energy of the triton to be of order 80 keV. When corrections for this effect are made in an 18-channel momentum-space Faddeev calculation, we find the Paris and Argonne v 14 potentials triton binding energies that differ by only 20 keV 18. Adjoint string breaking in the pseudoparticle approach International Nuclear Information System (INIS) Szasz, Christian; Wagner, Marc 2008-01-01 We apply the pseudoparticle approach to SU(2) Yang-Mills theory and perform a detailed study of the potential between two static charges for various representations. Whereas for charges in the fundamental representation we find a linearly rising confining potential, we clearly observe string breaking, when considering charges in the adjoint representation. We also demonstrate Casimir scaling and compute gluelump masses for different spin and parity. Numerical results are in qualitative agreement with lattice results. 19. Missed retinal breaks in rhegmatogenous retinal detachment Directory of Open Access Journals (Sweden) Brijesh Takkar 2016-12-01 Full Text Available AIM: To evaluate the causes and associations of missed retinal breaks (MRBs and posterior vitreous detachment (PVD in patients with rhegmatogenous retinal detachment (RRD. METHODS: Case sheets of patients undergoing vitreo retinal surgery for RRD at a tertiary eye care centre were evaluated retrospectively. Out of the 378 records screened, 253 were included for analysis of MRBs and 191 patients were included for analysis of PVD, depending on the inclusion criteria. Features of RRD and retinal breaks noted on examination were compared to the status of MRBs and PVD detected during surgery for possible associations. RESULTS: Overall, 27% patients had MRBs. Retinal holes were commonly missed in patients with lattice degeneration while missed retinal tears were associated with presence of complete PVD. Patients operated for cataract surgery were significantly associated with MRBs (P=0.033 with the odds of missing a retinal break being 1.91 as compared to patients with natural lens. Advanced proliferative vitreo retinopathy (PVR and retinal bullae were the most common reasons for missing a retinal break during examination. PVD was present in 52% of the cases and was wrongly assessed in 16%. Retinal bullae, pseudophakia/aphakia, myopia, and horse shoe retinal tears were strongly associated with presence of PVD. Traumatic RRDs were rarely associated with PVD. CONCLUSION: Pseudophakic patients, and patients with retinal bullae or advanced PVR should be carefully screened for MRBs. Though Weiss ring is a good indicator of PVD, it may still be over diagnosed in some cases. PVD is associated with retinal bullae and pseudophakia, and inversely with traumatic RRD. 20. Effective potential and chiral symmetry breaking International Nuclear Information System (INIS) Hochberg, David 2010-01-01 The nonequilibrium effective potential is calculated for the Frank model of spontaneous mirror-symmetry breaking in chemistry in which external noise is introduced to account for random environmental effects. The well-mixed limit, corresponding to negligible diffusion, and the case of diffusion in two space dimensions are studied in detail. White noise has a disordering effect in the former case, whereas in the latter case a phase transition occurs for external noise exceeding a critical intensity which racemizes the system. 1. The Beam Break-Up Numerical Simulator International Nuclear Information System (INIS) Travish, G.A. 1989-11-01 Beam Break-Up (BBU) is a severe constraint in accelerator design, limiting beam current and quality. The control of BBU has become the focus of much research in the design of the next generation collider, recirculating and linear induction accelerators and advanced accelerators. Determining the effect on BBU of modifications to cavities, the focusing elements or the beam is frequently beyond the ability of current analytic models. A computer code was written to address this problem. The Beam Break-Up Numerical Simulator (BBUNS) was designed to numerically solve for beam break-up (BBU) due to an arbitrary transverse wakefield. BBUNS was developed to be as user friendly as possible on the Cray computer series. The user is able to control all aspects of input and output by using a single command file. In addition, the wakefield is specified by the user and read in as a table. The program can model energy variations along and within the beam, focusing magnetic field profiles can be specified, and the graphical output can be tailored. In this note we discuss BBUNS, its structure and application. Included are detailed instructions, examples and a sample session of BBUNS. This program is available for distribution. 50 refs., 18 figs., 5 tabs 2. Enhanced breaking of heavy quark spin symmetry Energy Technology Data Exchange (ETDEWEB) Guo, Feng-Kun, E-mail: fkguo@hiskp.uni-bonn.de [Helmholtz-Institut für Strahlen- und Kernphysik and Bethe Center for Theoretical Physics, Universität Bonn, D-53115 Bonn (Germany); Meißner, Ulf-G., E-mail: meissner@hiskp.uni-bonn.de [Helmholtz-Institut für Strahlen- und Kernphysik and Bethe Center for Theoretical Physics, Universität Bonn, D-53115 Bonn (Germany); Institute for Advanced Simulation, Institut für Kernphysik and Jülich Center for Hadron Physics, Forschungszentrum Jülich, D-52425 Jülich (Germany); Shen, Cheng-Ping, E-mail: shencp@ihep.ac.cn [School of Physics and Nuclear Energy Engineering, Beihang University, Beijing 100191 (China) 2014-11-10 Heavy quark spin symmetry is useful to make predictions on ratios of decay or production rates of systems involving heavy quarks. The breaking of spin symmetry is generally of the order of O(Λ{sub QCD}/m{sub Q}), with Λ{sub QCD} the scale of QCD and m{sub Q} the heavy quark mass. In this paper, we will show that a small S- and D-wave mixing in the wave function of the heavy quarkonium could induce a large breaking in the ratios of partial decay widths. As an example, we consider the decays of the ϒ(10860) into the χ{sub bJ}ω(J=0,1,2), which were recently measured by the Belle Collaboration. These decays exhibit a huge breaking of the spin symmetry relation were the ϒ(10860) a pure 5S bottomonium state. We propose that this could be a consequence of a mixing of the S-wave and D-wave components in the ϒ(10860). Prediction on the ratio Γ(ϒ(10860)→χ{sub b0}ω)/Γ(ϒ(10860)→χ{sub b2}ω) is presented assuming that the decay of the D-wave component is dominated by the coupled-channel effects. 3. Dormancy Breaking in Ormosia arborea Seeds Directory of Open Access Journals (Sweden) Edilma Pereira Gonçalves 2011-01-01 Full Text Available Ormosia arborea is a tree species planted in urban areas and used to restore degraded areas. Its seeds are dormant and propagation is difficult. This study compares different dormancy breaking methods and physiological seed quality and seedling production. The seeds were germinated in sand in the laboratory of the Universidade Estadual de Santa Cruz, Ilhéus, Bahia, Brazil. The following dormancy breaking treatments were applied: control (intact seeds, 100°C water immersion; boiling water immersion followed by 24 hours of soaking; scarification with number 100 and number 50 sandpaper opposite from root emergence; sulfuric acid immersion for 1 hour, 50, 45, and 30 minutes. Seed immersion in 100°C and boiling water did not break the dormancy. The study species showed a greater vigor of seedling when its seeds were submitted to treatments associated with tegument rupturing by sandpaper or sulfuric acid. On the other hand, seed scarification with sulfuric acid for 1 hour, 50, 45, and 30 minutes or sandpaper favored seed germination and vigor. 4. Phenomenology of GUT-less Supersymmetry Breaking CERN Document Server Ellis, Jonathan Richard; Sandick, Pearl 2007-01-01 We study models in which supersymmetry breaking appears at an intermediate scale, M_{in}, below the GUT scale. We assume that the soft supersymmetry-breaking parameters of the MSSM are universal at M_{in}, and analyze the morphology of the constraints from cosmology and collider experiments on the allowed regions of parameter space as M_{in} is reduced from the GUT scale. We present separate analyses of the (m_{1/2},m_0) planes for tan(beta)=10 and tan(beta)=50, as well as a discussion of non-zero trilinear couplings, A_0. Specific scenarios where the gaugino and scalar masses appear to be universal below the GUT scale have been found in mirage-mediation models, which we also address here. We demand that the lightest neutralino be the LSP, and that the relic neutralino density not conflict with measurements by WMAP and other observations. At moderate values of M_{in}, we find that the allowed regions of the (m_{1/2},m_0) plane are squeezed by the requirements of electroweak symmetry breaking and that the ligh... 5. A comparison of lateral ankle ligament suture anchor strength. Science.gov (United States) Barber, F Alan; Herbert, Morley A; Crates, John M 2013-06-01 Lateral ankle ligament repairs increasingly use suture anchors instead of bone tunnels. Our purpose was to compare the biomechanical properties of a knotted and knotless suture anchor appropriate for a lateral ankle ligament reconstruction. In porcine distal fibulae, 10 samples of 2 different PEEK anchors were inserted. The attached sutures were cyclically loaded between 10N and 60N for 200 cycles. A destructive pull was performed and failure loads, cyclic displacement, stiffness, and failure mode recorded. PushLock 2.5 anchors failed before 200 cycles. PushLock 100 cycle displacement was less than Morphix 2.5 displacement (panchors completing 200 cycles was 86.5N (PushLock) and 252.1N (Morphix) (panchor breaking and suture breakage. The knotted Morphix demonstrated more displacement and greater failure strength than the knotless PushLock. The PushLock failed consistently with suture breaking. The Morphix anchor failed both by anchor breaking and by suture breaking. Copyright © 2012 European Foot and Ankle Society. Published by Elsevier Ltd. All rights reserved. 6. A model for string-breaking in QCD International Nuclear Information System (INIS) Antonov, Dmitri; Del Debbio, Luigi; Di Giacomo, Adriano 2003-01-01 We present a model for string breaking based on the existence of chromoelectric flux tubes. We predict the form of the long-range potential and obtain an estimate of the string breaking length. A prediction is also obtained for the behaviour with temperature of the string breaking length near the deconfinement phase transition. We plan to use this model as a guide for a program of study of string breaking on the lattice. (author) 7. Fast Times During Spring Breaks: Are Traffic Fatalities Another Consequence? OpenAIRE French, Michael; Gumus, Gulcin 2014-01-01 Every year in the United States, millions of college students travel for spring break, spending billions of dollars. We examine a potential adverse consequence of spring break that has received little attention in the literature - traffic safety. In particular, we estimate the impact of spring break season on fatal passenger vehicle crashes. Using daily county-level longitudinal data on traffic fatalities in popular spring break destinations from 1982-2011, we conduct separate analyses by age... 8. Radiative breaking of cosmologically acceptable grand unified theories International Nuclear Information System (INIS) Gato, B.; Leon, J.; Quiros, M. 1984-01-01 We present a cosmologically acceptable grand unified model where the breaking of SU(5) proceeds through radiative corrections induced by supergravity soft-breaking terms. The breaking scale is determined by dimensional transmutation. The model is compatible with the radiative breaking of SU(2)sub(L)xU(1)sub(Y) which provides an experimentally accessible low energy particle spectrum and small top quark mass. (orig.) 9. Strength degradation of oxidized graphite support column in VHTR International Nuclear Information System (INIS) Park, Byung Ha; No, Hee Cheon 2010-01-01 Air-ingress events caused by large pipe breaks are important accidents considered in the design of Very High Temperature Gas-Cooled Reactors (VHTRs). A main safety concern for this type of event is the possibility of core collapse following the failure of the graphite support column, which can be oxidized by ingressed air. In this study, the main target is to predict the strength of the oxidized graphite support column. Through compression tests for fresh and oxidized graphite columns, the compressive strength of IG-110 was obtained. The buckling strength of the IG-110 column is expressed using the following empirical straight-line formula: σ cr,buckling =91.34-1.01(L/r). Graphite oxidation in Zone 1 is volume reaction and that in Zone 3 is surface reaction. We notice that the ultimate strength of the graphite column oxidized in Zones 1 and 3 only depends on the slenderness ratio and bulk density. Its strength degradation oxidized in Zone 1 is expressed in the following nondimensional form: σ/σ 0 =exp(-kd), k=0.114. We found that the strength degradation of a graphite column, oxidized in Zone 3, follows the above buckling empirical formula as the slenderness of the column changes. (author) 10. Strengths only or strengths and relative weaknesses? A preliminary study. Science.gov (United States) Rust, Teri; Diessner, Rhett; Reade, Lindsay 2009-10-01 Does working on developing character strengths and relative character weaknesses cause lower life satisfaction than working on developing character strengths only? The present study provides a preliminary answer. After 76 college students completed the Values in Action Inventory of Strengths (C. Peterson & M. E. P. Seligman, 2004), the authors randomly assigned them to work on 2 character strengths or on 1 character strength and 1 relative weakness. Combined, these groups showed significant gains on the Satisfaction With Life Scale (E. Diener, R. A. Emmons, R. J. Larsen, & S. Griffin, 1985), compared with a 32-student no-treatment group. However, there was no significant difference in gain scores between the 2-strengths group and the 1-character-strength-and-1-relative-character-weakness group. The authors discuss how focusing on relative character weaknesses (along with strengths) does not diminish-and may assist in increasing-life satisfaction. 11. Breaking Boundaries: Complementary and Alternative Medicine Provider Framing of Preventive Care. Science.gov (United States) Agarwal, Vinita 2017-11-01 This textual examination extends understandings of how complementary and alternative medicine (CAM) providers constitute preventive care in their discourse by identifying the frame of breaking boundaries referencing relational, structural, and philosophical orientations in their practice with their clients. Analysis of semistructured, in-depth interviews with CAM providers ( n = 17) reveals that the frame of breaking boundaries was comprised of three themes: finding one's own strength; I don't prescribe, so I'm exploring; and ground yourself, and have an escape route. The themes describe preventive care by identifying how CAM providers negotiate their relational positionality in connecting with clients, structural positionality within the field of health care, and philosophical positionality within the ontological understandings that guide how health is defined and conceptualized. The study contributes toward enhancing diverse understandings of constituting preventive care in practice and suggests pragmatic implications for addressing biomedical provider communication with their patients seeking CAM care alongside conventional treatments. 12. Effects of tissue mechanical properties on susceptibility to histotripsy-induced tissue damage Science.gov (United States) Vlaisavljevich, Eli; Kim, Yohan; Owens, Gabe; Roberts, William; Cain, Charles; Xu, Zhen 2014-01-01 Histotripsy is a non-invasive tissue ablation method capable of fractionating tissue by controlling acoustic cavitation. To determine the fractionation susceptibility of various tissues, we investigated histotripsy-induced damage on tissue phantoms and ex vivo tissues with different mechanical strengths. A histotripsy bubble cloud was formed at tissue phantom surfaces using 5-cycle long ultrasound pulses with peak negative pressure of 18 MPa and PRFs of 10, 100, and 1000 Hz. Results showed significantly smaller lesions were generated in tissue phantoms of higher mechanical strength. Histotripsy was also applied to 43 different ex vivo porcine tissues with a wide range of mechanical properties. Gross morphology demonstrated stronger tissues with higher ultimate stress, higher density, and lower water content were more resistant to histotripsy damage in comparison to weaker tissues. Based on these results, a self-limiting vessel-sparing treatment strategy was developed in an attempt to preserve major vessels while fractionating the surrounding target tissue. This strategy was tested in porcine liver in vivo. After treatment, major hepatic blood vessels and bile ducts remained intact within a completely fractionated liver volume. These results identify varying susceptibilities of tissues to histotripsy therapy and provide a rational basis to optimize histotripsy parameters for treatment of specific tissues. 13. Breaking Waves on the Ocean Surface Science.gov (United States) Schwendeman, Michael S. In the open ocean, breaking waves are a critical mechanism for the transfer of energy, momentum, and mass between the atmosphere and the ocean. Despite much study, fundamental questions about wave breaking, such as what determines whether a wave will break, remain unresolved. Measurements of oceanic breakers, or "whitecaps," are often used to validate the hypotheses derived in simplified theoretical, numerical, or experimental studies. Real-world measurements are also used to improve the parameterizations of wave-breaking in large global models, such as those forecasting climate change. Here, measurements of whitecaps are presented using ship-based cameras, from two experiments in the North Pacific Ocean. First, a method for georectifying the camera imagery is described using the distant horizon, without additional instrumentation. Over the course of the experiment, this algorithm correctly identifies the horizon in 92% of images in which it is visible. In such cases, the calculation of camera pitch and roll is accurate to within 1 degree. The main sources of error in the final georectification are from mislabeled horizons due to clouds, rain, or poor lighting, and from vertical "heave" motions of the camera, which cannot be calculated with the horizon method. This method is used for correcting the imagery from the first experiment, and synchronizing the imagery from the second experiment to an onboard inertial motion package. Next, measurements of the whitecap coverage, W, are shown from both experiments. Although W is often used in models to represent whitecapping, large uncertainty remains in the existing parameterizations. The data show good agreement with recent measurements using the wind speed. Although wave steepness and dissipation are hypothesized to be more robust predictors of W, this is shown to not always be the case. Wave steepness shows comparable success to the wind parameterizations only when using a mean-square slope variable calculated over the 14. Strength Training: For Overall Fitness Science.gov (United States) Healthy Lifestyle Fitness Strength training is an important part of an overall fitness program. Here's what strength training can do for ... is a key component of overall health and fitness for everyone. Lean muscle mass naturally diminishes with ... 15. Cosmology with equivalence principle breaking in the dark sector International Nuclear Information System (INIS) Keselman, Jose Ariel; Nusser, Adi; Peebles, P. J. E. 2010-01-01 A long-range force acting only between nonbaryonic particles would be associated with a large violation of the weak equivalence principle. We explore cosmological consequences of this idea, which we label ReBEL (daRk Breaking Equivalence principLe). A high resolution hydrodynamical simulation of the distributions of baryons and dark matter confirms our previous findings that a ReBEL force of comparable strength to gravity on comoving scales of about 1 h -1 Mpc causes voids between the concentrations of large galaxies to be more nearly empty, suppresses accretion of intergalactic matter onto galaxies at low redshift, and produces an early generation of dense dark-matter halos. A preliminary analysis indicates the ReBEL scenario is consistent with the one-dimensional power spectrum of the Lyman-Alpha forest and the three-dimensional galaxy autocorrelation function. Segregation of baryons and DM in galaxies and systems of galaxies is a strong prediction of ReBEL. ReBEL naturally correlates the baryon mass fraction in groups and clusters of galaxies with the system mass, in agreement with recent measurements. 16. Breaking Out of the Local: International dimensions of science shops Directory of Open Access Journals (Sweden) Caspar DeBok 2008-09-01 Full Text Available In this article we want to give an overview of the international dimension and the interest of the European Union (EU in the concept of Science Shops. The European Commission (EC manages the day-to-day business by initiating and implementing EU policies and spending EU funds. The EC support for Science Shops has been an important factor for the international interest and progress of the Science Shop movement. This article will not give detailed information about daily routines of a Science Shop. Detailed information about the Science Shop concept can be found at the Living Knowledge website (www.livingknowledge.org. Living Knowledge represents the international Science Shop Network. In this article international developments of the Science Shop Network, like the project TRAMS, and Science Shop backgrounds will be linked with past and new EU policies like the EU 7th Framework Programme for Research. It shows how community-based research does not only have a local dimension. The international Science Shop activities show the strengths of international cooperation to break out of the local and to bring local issues on the international agenda. Detailed information about the Science Shop concept and daily routines of a Science Shop can be found at the Living Knowledge website (www.livingknowledge.org, e.g. at the FAQ section and in the toolbox. 17. Thermal damage control of dye-assisted laser tissue welding: effect of dye concentration Science.gov (United States) Xie, Hua; Buckley, Lisa A.; Prahl, Scott A.; Shaffer, Brian S.; Gregory, Kenton W. 2001-05-01 Successful laser-assisted tissue welding was implemented to provide proper weld strength with minimized tissue thermal injury. We investigated and compared the weld strengths and morphologic changes in porcine small intestinal submucose (SIS) and porcine ureteral tissues with various concentration of indocyanine green (ICG) and with a solid albumin sheet. The study showed that the tissues were welded at lower ICG concentration (0.05 mM) with minimized tissue thermal damage using an 800-nm wavelength diode laser. 18. Sparticle spectrum and constraints in anomaly mediated supersymmetry breaking models International Nuclear Information System (INIS) Huitu, K.; Laamanen, J.; Pandita, P.N. 2002-01-01 We study in detail the particle spectrum in anomaly mediated supersymmetry breaking models in which supersymmetry breaking terms are induced by the super-Weyl anomaly. We investigate the minimal anomaly mediated supersymmetry breaking models, gaugino assisted supersymmetry breaking models, as well as models with additional residual nondecoupling D-term contributions due to an extra U(1) gauge symmetry at a high energy scale. We derive sum rules for the sparticle masses in these models which can help in differentiating between them. We also obtain the sparticle spectrum numerically, and compare and contrast the results so obtained for the different types of anomaly mediated supersymmetry breaking models 19. Computational simulation of chromosome breaks in human liver International Nuclear Information System (INIS) Yang Jianshe; Li Wenjian; Jin Xiaodong 2006-01-01 An easy method was established for computing chromosome breaks in cells exposed to heavily charged particles. The cell chromosome break value by 12 C +6 ions was theoretically calculated, and was tested with experimental data of chromosome breaks by using a premature chromosome condensation technique. The theoretical chromosome break value agreed well with the experimental data. The higher relative biological effectiveness of the heavy ions was closely correlated to its physical characteristics. In addition, the chromosome break value can be predicted off line. (authors) 20. Anisotropic toughness and strength in graphene and its atomistic origin Science.gov (United States) Hossain, M. Zubaer; Ahmed, Tousif; Silverman, Benjamin; Khawaja, M. Shehroz; Calderon, Justice; Rutten, Andrew; Tse, Stanley 2018-01-01 This paper presents the implication of crystallographic orientation on toughness and ideal strength in graphene under lattice symmetry-preserving and symmetry-breaking deformations. In symmetry-preserving deformation, both toughness and strength are isotropic, regardless of the chirality of the lattice; whereas, in symmetry-breaking deformation they are strongly anisotropic, even in the presence of vacancy defects. The maximum and minimum of toughness or strength occur for loading along the zigzag direction and the armchair direction, respectively. The anisotropic behavior is governed by a complex interplay among bond-stretching deformation, bond-bending deformation, and the chirality of the lattice. Nevertheless, the condition for crack-nucleation is dictated by the maximum bond-force required for bond rupture, and it is independent of the chiral angle of the lattice or loading direction. At the onset of crack-nucleation a localized nucleation zone is formed, wherein the bonds rupture locally satisfying the maximum bond-force criterion. The nucleation zone acts as the physical origin in triggering the fracture nucleation process, but its presence is undetectable from the macroscopic stress-strain data. 1. Best estimate small break LOCA analysis for KNGR SIS optimization International Nuclear Information System (INIS) Song, JIn Ho; Lim, Hong Sik; Bae, Kyoo Hwan; Lee, Joon 1996-01-01 The KNGR has an advanced ECCS design feature which employs four mechanically-separated SI trains where each train consisting of one HPSI pump and one SIT injects ECC water directly into the reactor vessel downcomer annulus. To demonstrate that the KNGR ECCS design features meet the EPRI ALWR requirements of no core uncovery for a break of up to 6 inch diameter, small break LOCA cases with various break sizes were analyzed using a best-estimate analytical procedure. Two kinds of break locations are considered: cold leg and DVI line breaks. It was observed that the KNGR ECCS design can tolerate a cold leg break of up to 10 inches with no core uncovery. However, since DVI line break with 6 inch diameter undergoes slight core uncovery, further investigation is required for KNGR SIS optimization 2. Climate and floods still govern California levee breaks Science.gov (United States) Florsheim, J.L.; Dettinger, M.D. 2007-01-01 Even in heavily engineered river systems, climate still governs flood variability and thus still drives many levee breaks and geomorphic changes. We assemble a 155-year record of levee breaks for a major California river system to find that breaks occurred in 25% of years during the 20th Century. A relation between levee breaks and river discharge is present that sets a discharge threshold above which most levee breaks occurred. That threshold corresponds to small floods with recurrence intervals of ???2-3 years. Statistical analysis illustrates that levee breaks and peak discharges cycle (broadly) on a 12-15 year time scale, in time with warm-wet storm patterns in California, but more slowly or more quickly than ENSO and PDO climate phenomena, respectively. Notably, these variations and thresholds persist through the 20th Century, suggesting that historical flood-control effects have not reduced the occurrence or frequency of levee breaks. Copyright 2007 by the American Geophysical Union. 3. High-Tensile Strength Tape Versus High-Tensile Strength Suture: A Biomechanical Study. Science.gov (United States) Gnandt, Ryan J; Smith, Jennifer L; Nguyen-Ta, Kim; McDonald, Lucas; LeClere, Lance E 2016-02-01 To determine which suture design, high-tensile strength tape or high-tensile strength suture, performed better at securing human tissue across 4 selected suture techniques commonly used in tendinous repair, by comparing the total load at failure measured during a fixed-rate longitudinal single load to failure using a biomechanical testing machine. Matched sets of tendon specimens with bony attachments were dissected from 15 human cadaveric lower extremities in a manner allowing for direct comparison testing. With the use of selected techniques (simple Mason-Allen in the patellar tendon specimens, whip stitch in the quadriceps tendon specimens, and Krackow stitch in the Achilles tendon specimens), 1 sample of each set was sutured with a 2-mm braided, nonabsorbable, high-tensile strength tape and the other with a No. 2 braided, nonabsorbable, high-tensile strength suture. A total of 120 specimens were tested. Each model was loaded to failure at a fixed longitudinal traction rate of 100 mm/min. The maximum load and failure method were recorded. In the whip stitch and the Krackow-stitch models, the high-tensile strength tape had a significantly greater mean load at failure with a difference of 181 N (P = .001) and 94 N (P = .015) respectively. No significant difference was found in the Mason-Allen and simple stitch models. Pull-through remained the most common method of failure at an overall rate of 56.7% (suture = 55%; tape = 58.3%). In biomechanical testing during a single load to failure, high-tensile strength tape performs more favorably than high-tensile strength suture, with a greater mean load to failure, in both the whip- and Krackow-stitch models. Although suture pull-through remains the most common method of failure, high-tensile strength tape requires a significantly greater load to pull-through in a whip-stitch and Krakow-stitch model. The biomechanical data obtained in the current study indicates that high-tensile strength tape may provide better repair 4. Break spectrum analyses for small break loss of coolant accidents in a RESAR-3S Plant International Nuclear Information System (INIS) Fletcher, C.D.; Kullberg, C.M. 1986-03-01 A series of thermal-hydraulic analyses were performed to investigate phenomena occurring during small break loss-of-coolant-accident (LOCA) sequences in a RESAR-3S pressurized water reactor. The analysis included simulations of plant behavior using the TRAC-PF1 and RELAP5/MOD2 computer codes. Series of calculations were performed using both codes for different break sizes. The analyses presented here also served an audit function in that the results shown here were used by the US Nuclear Regulatory Commission (NRC) as an independent confirmation of similar analyses performed by Westinghouse Electric Company using another computer code. 10 refs., 62 figs., 14 tabs 5. Electroweak Symmetry Breaking (3/3) CERN Multimedia CERN. Geneva 2012-01-01 The focus of the lectures will be on the role of the Higgs boson in the mechanism of electroweak symmetry breaking, both in the Standard Model and in models of New Physics. In particular, I will discuss how a determination of its couplings to matter and gauge fields can give important information on the nature and origin of the Higgs boson. I will thus review the picture on Higgs couplings implied by the current experimental data and examine further interesting processes that can be measured in the future. 6. Electroweak Symmetry Breaking (2/3) CERN Multimedia CERN. Geneva 2012-01-01 The focus of the lectures will be on the role of the Higgs boson in the mechanism of electroweak symmetry breaking, both in the Standard Model and in models of New Physics. In particular, I will discuss how a determination of its couplings to matter and gauge fields can give important information on the nature and origin of the Higgs boson. I will thus review the picture on Higgs couplings implied by the current experimental data and examine further interesting processes that can be measured in the future. 7. Electroweak Symmetry Breaking (1/3) CERN Multimedia CERN. Geneva 2012-01-01 The focus of the lectures will be on the role of the Higgs boson in the mechanism of electroweak symmetry breaking, both in the Standard Model and in models of New Physics. In particular, I will discuss how a determination of its couplings to matter and gauge fields can give important information on the nature and origin of the Higgs boson. I will thus review the picture on Higgs couplings implied by the current experimental data and examine further interesting processes that can be measured in the future. 8. Mechanically controllable break junctions for molecular electronics. Science.gov (United States) Xiang, Dong; Jeong, Hyunhak; Lee, Takhee; Mayer, Dirk 2013-09-20 A mechanically controllable break junction (MCBJ) represents a fundamental technique for the investigation of molecular electronic junctions, especially for the study of the electronic properties of single molecules. With unique advantages, the MCBJ technique has provided substantial insight into charge transport processes in molecules. In this review, the techniques for sample fabrication, operation and the various applications of MCBJs are introduced and the history, challenges and future of MCBJs are discussed. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. 9. Breaking the fault tree circular logic International Nuclear Information System (INIS) Lankin, M. 2000-01-01 Event tree - fault tree approach to model failures of nuclear plants as well as of other complex facilities is noticeably dominant now. This approach implies modeling an object in form of unidirectional logical graph - tree, i.e. graph without circular logic. However, genuine nuclear plants intrinsically demonstrate quite a few logical loops (circular logic), especially where electrical systems are involved. This paper shows the incorrectness of existing practice of circular logic breaking by elimination of part of logical dependencies and puts forward a formal algorithm, which enables the analyst to correctly model the failure of complex object, which involves logical dependencies between system and components, in form of fault tree. (author) 10. Leak before break experience in CANDU reactors International Nuclear Information System (INIS) Price, E.G.; Moan, G.D.; Coleman, C.E. 1988-04-01 The paper describes how the requirements for Leak-Before-Break are met in CANDU reactors. The requirements are based on operational and laboratory experience. After the onset of leakage in a fuel channel from a delayed hydride crack, time is available to the operator to take action before the crack grows to an unstable length. The time available is calculated using different models which use crack growth data from small specimen tests. When the results from crack growth behaviour experiments, carried out on components removed from reactor are used in the model, the time available for operator response is about 100 hours 11. SU(3) flavour breaking and baryon structure Energy Technology Data Exchange (ETDEWEB) Cooke, A.N.; Horsley, R. [Edinburgh Univ. (United Kingdom). School of Physics and Astronomy; Nakamura, Y. [RIKEN Advanced Institute for Computational Science, Kobe, Hyogo (Japan); Pleiter, D. [Forschungszentrum Juelich GmbH (Germany). Juelich Supercomputing Centre (JSC); Regensburg Univ. (Germany). Institut fuer Theoretische Physik; Rakow, P.E.L. [Liverpool Univ. (United Kingdom). Theoretical Physics Div.; Shanahan, P.; Zanotti, J.M. [Adelaide Univ., SA (Australia). CSSM, School of Chemistry and Physics; Schierholz, G. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Stueben, H. [Hamburg Univ. (Germany). Regionales Rechenzentrum; Collaboration: QCDSF/UKQCD Collaboration 2013-11-15 We present results from the QCDSF/UKQCD collaboration for hyperon electromagnetic form factors and axial charges obtained from simulations using N{sub f}=2+1 flavours of O(a)-improved Wilson fermions. We also consider matrix elements relevant for hyperon semileptonic decays. We find flavour-breaking effects in hyperon magnetic moments which are consistent with experiment, while our results for the connected quark spin content indicates that quarks contribute more to the spin of the {Xi} baryon than they do to the proton. 12. Electroweak symmetry breaking beyond the Standard Model International Nuclear Information System (INIS) Bhattacharyya, Gautam 2012-01-01 In this paper, two key issues related to electroweak symmetry breaking are addressed. First, how fine-tuned different models are that trigger this phenomenon? Second, even if a light Higgs boson exists, does it have to be necessarily elementary? After a brief introduction, the fine-tuning aspects of the MSSM, NMSSM, generalized NMSSM and GMSB scenarios shall be reviewed, then the little Higgs, composite Higgs and the Higgsless models shall be compared. Finally, a broad overview will be given on where we stand at the end of 2011. (author) 13. Phenomenology of flavor-mediated supersymmetry breaking International Nuclear Information System (INIS) Kaplan, D. Elazzar; Kribs, Graham D. 2000-01-01 The phenomenology of a new economical supersymmetric model that utilizes dynamical supersymmetry breaking and gauge mediation for the generation of the sparticle spectrum and the hierarchy of fermion masses is discussed. Similarities between the communication of supersymmetry breaking through a messenger sector and the generation of flavor using the Froggatt-Nielsen (FN) mechanism are exploited, leading to the identification of vector-like messenger fields with FN fields and the messenger U(1) as a flavor symmetry. An immediate consequence is that the first and second generation scalars acquire flavor-dependent masses, but do not violate flavor changing neutral current bounds since their mass scale, consistent with ''effective supersymmetry,'' is of order 10 TeV. We define and advocate a ''minimal flavor-mediated model'' (MFMM), recently introduced in the literature, which successfully accommodates the small flavor-breaking parameters of the standard model using order 1 couplings and ratios of flavon field VEVs. The mediation of supersymmetry breaking occurs via two-loop logarithm-enhanced gauge-mediated contributions, as well as several one-loop and two-loop Yukawa-mediated contributions for which we provide analytical expressions. The MFMM is parametrized by a small set of masses and couplings, with values restricted by several model constraints and experimental data. Full two-loop renormalization group evolution is performed, correctly taking into account the negative two-loop gauge contributions from heavy first and second generations. Electroweak symmetry is radiatively broken with the value of μ determined by matching to the Z mass. The weak scale spectrum is generally rather heavy, except for the lightest Higgs boson, the lightest stau, the lightest chargino, the lightest two neutralinos, and of course a very light gravitino. The next-to-lightest sparticle always has a decay length that is larger than the scale of a detector, and is either the lightest stau 14. Density Functional Simulation of a Breaking Nanowire DEFF Research Database (Denmark) Nakamura, A.; Brandbyge, Mads; Hansen, Lars Bruno 1999-01-01 to a specific number of eigenchannels. The transitions between plateaus can be abrupt in connection with structural rearrangements or extend over a few a of elongation. The interplay between conductance modes and structural deformation is discussed by means of the eigenchannel transmission probabilities.......We study the deformation and breaking of an atomic-sized sodium wire using density functional simulations. The wire deforms through sudden atomic rearrangements and smoother atomic displacements. The conductance of the wire exhibits plateaus at integer values in units of 2e(2)/h corresponding... 15. Cosmoparticle physics of family symmetry breaking International Nuclear Information System (INIS) Khlopov, M.Yu. 1993-07-01 The foundations of both particle theory and cosmology are hidden at super energy scale and can not be tested by direct laboratory means. Cosmoparticle physics is developed to probe these foundations by the proper combination of their indirect effects, thus providing definite conclusions on their reliability. Cosmological and astrophysical tests turn to be complementary to laboratory searches of rare processes, induced by new physics, as it can be seen in the case of gauge theory of broken symmetry of quark and lepton families, ascribing to the hierarchy of the horizontal symmetry breaking the observed hierarchy of masses and the mixing between quark and lepton families. 36 refs 16. Several ways of breaking the colour symmetry International Nuclear Information System (INIS) Krolikowski, W. 1975-01-01 We discuss some cases of colour-symmetry breaking and its implications for quark binding by one-gluon-exchange forces. We pay special attention to the case, where colour-isospin and colour-hypercharge subsymmetries are preserved. Then, the ω-PHI-like mixing of colour-nonet components 0 and 8 leads to a Zweig-type approximate selection rule for decays of PHI-like meson = antiqsub(B)qsub(B)(qsub(B) is the '' blue'' quark) into ordinary mesons (and photons). (author) 17. Wave-induced stress and breaking of sea ice in a coupled hydrodynamic discrete-element wave-ice model Science.gov (United States) Herman, Agnieszka 2017-11-01 In this paper, a coupled sea ice-wave model is developed and used to analyze wave-induced stress and breaking in sea ice for a range of wave and ice conditions. The sea ice module is a discrete-element bonded-particle model, in which ice is represented as cuboid grains floating on the water surface that can be connected to their neighbors by elastic joints. The joints may break if instantaneous stresses acting on them exceed their strength. The wave module is based on an open-source version of the Non-Hydrostatic WAVE model (NHWAVE). The two modules are coupled with proper boundary conditions for pressure and velocity, exchanged at every wave model time step. In the present version, the model operates in two dimensions (one vertical and one horizontal) and is suitable for simulating compact ice in which heave and pitch motion dominates over surge. In a series of simulations with varying sea ice properties and incoming wavelength it is shown that wave-induced stress reaches maximum values at a certain distance from the ice edge. The value of maximum stress depends on both ice properties and characteristics of incoming waves, but, crucially for ice breaking, the location at which the maximum occurs does not change with the incoming wavelength. Consequently, both regular and random (Jonswap spectrum) waves break the ice into floes with almost identical sizes. The width of the zone of broken ice depends on ice strength and wave attenuation rates in the ice. 18. Gaussian discriminating strength Science.gov (United States) Rigovacca, L.; Farace, A.; De Pasquale, A.; Giovannetti, V. 2015-10-01 We present a quantifier of nonclassical correlations for bipartite, multimode Gaussian states. It is derived from the Discriminating Strength measure, introduced for finite dimensional systems in Farace et al., [New J. Phys. 16, 073010 (2014), 10.1088/1367-2630/16/7/073010]. As the latter the new measure exploits the quantum Chernoff bound to gauge the susceptibility of the composite system with respect to local perturbations induced by unitary gates extracted from a suitable set of allowed transformations (the latter being identified by posing some general requirements). Closed expressions are provided for the case of two-mode Gaussian states obtained by squeezing or by linearly mixing via a beam splitter a factorized two-mode thermal state. For these density matrices, we study how nonclassical correlations are related with the entanglement present in the system and with its total photon number. 19. Tissue irradiator International Nuclear Information System (INIS) Hungate, F.P.; Riemath, W.F.; Bunnell, L.R. 1975-01-01 A tissue irradiator is provided for the in-vivo irradiation of body tissue. The irradiator comprises a radiation source material contained and completely encapsulated within vitreous carbon. An embodiment for use as an in-vivo blood irradiator comprises a cylindrical body having an axial bore therethrough. A radioisotope is contained within a first portion of vitreous carbon cylindrically surrounding the axial bore, and a containment portion of vitreous carbon surrounds the radioisotope containing portion, the two portions of vitreous carbon being integrally formed as a single unit. Connecting means are provided at each end of the cylindrical body to permit connections to blood-carrying vessels and to provide for passage of blood through the bore. In a preferred embodiment, the radioisotope is thulium-170 which is present in the irradiator in the form of thulium oxide. A method of producing the preferred blood irradiator is also provided, whereby nonradioactive thulium-169 is dispersed within a polyfurfuryl alcohol resin which is carbonized and fired to form the integral vitreous carbon body and the device is activated by neutron bombardment of the thulium-169 to produce the beta-emitting thulium-170 20. Hyperscaling violation and electroweak symmetry breaking Energy Technology Data Exchange (ETDEWEB) Elander, Daniel, E-mail: pelander@purdue.edu [Department of Physics, Purdue University, 525 Northwestern Avenue, West Lafayette, IN 47907-2036 (United States); Lawrance, Robert; Piai, Maurizio [Department of Physics, College of Science, Swansea University, Singleton Park, Swansea, Wales (United Kingdom) 2015-08-15 We consider a class of simplified models of dynamical electroweak symmetry breaking built in terms of their five-dimensional weakly-coupled gravity duals, in the spirit of bottom-up holography. The sigma-model consists of two abelian gauge bosons and one real, non-charged scalar field coupled to gravity in five dimensions. The scalar potential is a simple exponential function of the scalar field. The background metric resulting from solving the classical equations of motion exhibits hyperscaling violation, at least at asymptotically large values of the radial direction. We study the spectrum of scalar composite states of the putative dual field theory by fluctuating the sigma-model scalars and gravity, and discuss in which cases we find a parametrically light scalar state in the spectrum. We model the spontaneous breaking of the (weakly coupled) gauge symmetry to the diagonal subgroup by the choice of IR boundary conditions. We compute the mass spectrum of spin-1 states, and the precision electroweak parameter S as a function of the hyperscaling coefficient. We find a general bound on the mass of the lightest spin-1 resonance, by requiring that the indirect bounds on the precision parameters be satisfied, that implies that precision electroweak physics excludes the possibility of a techni-rho meson with mass lighter than several TeV. 1. Rock Directed Breaking Under the Impulse Load Science.gov (United States) Khomeriki, Sergo; Mataradze, Edgar; Chikhradze, Nikoloz; Losaberidze, Marine; Khomeriki, Davit; Shatberashvili, Grigol 2016-10-01 In the work the problem of directed chipping of facing stone material by means of managing of explosion process is considered. The technology of the mining of decorative stone by the use of explosion energy means the very rapid transfer of potential energy of elastic deformations to kinetic energy. As a result, the explosion impulse, in the expanse of the inertia of rock massive, does not cause the increase of existing cracks. In the course of explosion, the shock wave is propagated by ultrasonic velocity and in this case the medium parameters (pressure, density, temperature, velocity) increase in spurts. In spite of this fact the all three conservation laws of mechanics remain valid on basis of three laws the equations are derived by which the parameters of shock wave may be defined by means of the rock physical-mechanical properties. The load on the body volume at breaking under explosion acts over very small period of the time. Therefore, stressed-deformed state of the rock was studied when the impulse load acts on the boundary. It was considered that the mining of the blocks of facing stone is performed from the hard rocks. This means that the breaking proceeds in the zone of elastic deformation. In the conditions of mentioned assumptions, the expression of the stress tensor and displacement of vector components initiated by stressed-deformed state in the rock are written. 2. Flavor symmetry breaking and meson masses International Nuclear Information System (INIS) Bhagwat, Mandar S.; Roberts, Craig D.; Chang Lei; Liu Yuxin; Tandy, Peter C. 2007-01-01 The axial-vector Ward-Takahashi identity is used to derive mass formulas for neutral pseudoscalar mesons. Flavor symmetry breaking entails nonideal flavor content for these states. Adding that the η ' is not a Goldstone mode, exact chiral-limit relations are developed from the identity. They connect the dressed-quark propagator to the topological susceptibility. It is confirmed that in the chiral limit the η ' mass is proportional to the matrix element which connects this state to the vacuum via the topological susceptibility. The implications of the mass formulas are illustrated using an elementary dynamical model, which includes an Ansatz for that part of the Bethe-Salpeter kernel related to the non-Abelian anomaly. In addition to the current-quark masses, the model involves two parameters, one of which is a mass-scale. It is employed in an analysis of pseudoscalar- and vector-meson bound-states. While the effects of SU(N f =2) and SU(N f =3) flavor symmetry breaking are emphasized, the five-flavor spectra are described. Despite its simplicity, the model is elucidative and phenomenologically efficacious; e.g., it predicts η-η ' mixing angles of ∼-15 deg. and π 0 -η angles of ∼1 deg 3. Dynamical supersymmetry breaking and gauge anomalies International Nuclear Information System (INIS) Zhang, H. 1991-01-01 Some aspects of supersymmetric gauge theories are discussed. It is shown that dynamical supersymmetry breaking does not occur in supersymmetric QED in higher dimensions. The cancellation of both local (perturbative) and global (non-perturbative) gauge anomalies are also discussed in supersymmetric gauge theories. We argue that there is no dynamical supersymmetry breaking in higher dimensions in any supersymmetric gauge theories free of gauge anomalies. It is also shown that for supersymmetric gauge theories in higher dimensions with a compact connected simple gauge group, when the local anomaly-free condition is satisfied, there can be at most a possible Z 2 global gauge anomaly in extended supersymmetric SO(10) (or spin (10)) gauge theories in D=10 dimensions containing additional Weyl fermions in a spinor representation of SO(10) (or spin (10)). In four dimensions with local anomaly-free condition satisfied, the only possible global gauge anomalies in supersymmetric gauge theories are Z 2 global gauge anomalies for extended supersymmetric SP(2N) (N=rank) gauge theories containing additional Weyl fermions in a representation of SP(2N) with an odd 2nd-order Dynkin index. (orig.) 4. Large-field inflation and supersymmetry breaking International Nuclear Information System (INIS) Buchmueller, Wilfried; Wieck, Clemens; Dudas, Emilian; Heurtier, Lucien; Ecole Polytechnique, Palaiseau 2014-07-01 Large-field inflation is an interesting and predictive scenario. Its non-trivial embedding in supergravity was intensively studied in the recent literature, whereas its interplay with supersymmetry breaking has been less thoroughly investigated. We consider the minimal viable model of chaotic inflation in supergravity containing a stabilizer field, and add a Polonyi field. Furthermore, we study two possible extensions of the minimal setup. We show that there are various constraints: first of all, it is very hard to couple an O'Raifeartaigh sector with the inflaton sector, the simplest viable option being to couple them only through gravity. Second, even in the simplest model the gravitino mass is bounded from above parametrically by the inflaton mass. Therefore, high-scale supersymmetry breaking is hard to implement in a chaotic inflation setup. As a separate comment we analyze the simplest chaotic inflation construction without a stabilizer field, together with a supersymmetrically stabilized Kaehler modulus. Without a modulus, the potential of such a model is unbounded from below. We show that a heavy modulus cannot solve this problem. 5. Supersymmetry breaking in 4D string theory International Nuclear Information System (INIS) De la Macorra, A.; Ross, G.G. 1995-01-01 We construct a (locally supersymmetric) four-fermion effective lagrangian description of the strong binding effects responsible for the formation of a gaugino condensate, extending the analysis to include the multiple moduli of orbifold compactification. Using this to estimate the binding we find that supersymmetry is broken and a phenomenologically realistic value for the gravitino mass and gauge coupling constant at the unification scale with only one gaugino condensate may be obtained. The main source for supersymmetry breaking is the VEV of the auxiliary field of the dilaton h s (i.e. h S >>h T , where T are moduli fields). By studying the scalar potential we find either that the vacuum expectation values of the moduli have a common value related to the vacuum expectation value of the dilaton or that they take the values of the dual invariant points. A squeezed orbifold can thus naturally be obtained, allowing for the possibility of minimal string unification. We include chiral matter fields and derive the scalar potential up to one-loop level. The one-loop potential is responsible for stabilising the scalar potential for vanishing vacuum expectation values of the chiral matter fields. We then calculate the soft supersymmetry breaking parameters in the visible sector. Finally we show that with a suitable choice of superpotential it is possible to cancel the cosmological constant while having supersymmetry broken. ((orig.)) 6. Osmocapsules for direct measurement of osmotic strength. Science.gov (United States) Kim, Shin-Hyun; Lee, Tae Yong; Lee, Sang Seok 2014-03-26 Monodisperse microcapsules with ultra-thin membranes are microfluidically designed to be highly sensitive to osmotic pressure, thereby providing a tool for the direct measurement of the osmotic strength. To make such osmocapsules, water-in-oil-in-water double-emulsion drops with ultra-thin shells are prepared as templates through emulsification of core-sheath biphasic flow in a capillary microfluidic device. When photocurable monomers are used as the oil phase, the osmocapsules are prepared by in-situ photopolymerization of the monomers, resulting in semipermeable membranes with a relatively large ratio of membrane thickness to capsule radius, approximately 0.02. These osmocapsules are buckled by the outward flux of water when they are subjected to a positive osmotic pressure difference above 125 kPa. By contrast, evaporation-induced consolidation of middle-phase containing polymers enables the production of osmocapsules with a small ratio of membrane thickness to capsule radius of approximately 0.002. Such an ultra-thin membrane with semi-permeability makes the osmocapsules highly sensitive to osmotic pressure; a positive pressure as small as 12.5 kPa induces buckling of the capsules. By employing a set of distinct osmocapsules confining aqueous solutions with different osmotic strengths, the osmotic strength of unknown solutions can be estimated through observation of the capsules that are selectively buckled. This approach provides the efficient measurement of the osmotic strength using only a very small volume of liquid, thereby providing a useful alternative to other measurement methods which use complex setups. In addition, in-vivo measurement of the osmotic strength can be potentially accomplished by implanting these biocompatible osmocapsules into tissue, which is difficult to achieve using conventional methods. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. 7. 'Jet breaks' and 'missing breaks' in the X-Ray afterglow of Gamma Ray Bursts CERN Document Server Dado, Shlomo; De Rújula, Alvaro 2008-01-01 The X-ray afterglows (AGs) of Gamma-Ray Bursts (GRBs) and X-Ray Flashes (XRFs) have, after the fast decline phase of their prompt emission, a temporal behaviour varying between two extremes. A large fraction of these AGs has a 'canonical' light curve which, after an initial shallow-decay 'plateau' phase, 'breaks smoothly' into a fast power-law decline. Very energetic GRBs, contrariwise, appear not to have a 'break', their AG declines like a power-law from the start of the observations. Breaks and 'missing breaks' are intimately related to the geometry and deceleration of the jets responsible for GRBs. In the frame of the 'cannonball' (CB) model of GRBs and XRFs, we analyze the cited extreme behaviours (canonical and pure power-law) and intermediate cases spanning the observed range of X-ray AG shapes. We show that the entire panoply of X-ray light-curve shapes --measured with Swift and other satellites-- are as anticipated, on very limpid grounds, by the CB model. We test the expected correlations between the... 8. Structural changes in Central and Eastern European economies: breaking news or breaking the ice? Czech Academy of Sciences Publication Activity Database Égert, B.; Jiménez-Rodríguez, R.; Kočenda, Evžen; Morales-Zumaquero, A. 2006-01-01 Roč. 39, 1-2 (2006), s. 85-103 ISSN 1573-9414 R&D Projects: GA MŠk LC542 Institutional research plan: CEZ:MSM0021620846 Keywords : Central and Eastern European (CEE) countries * multiple structural breaks * volatility Subject RIV: AH - Economics 9. Structural changes in transition economies: breaking the news or breaking the ice? Czech Academy of Sciences Publication Activity Database Égert, B.; Jiménez-Rodríguez, R.; Kočenda, Evžen; Morales-Zumaquero, A. -, č. 16 (2006), s. 1-15 Institutional research plan: CEZ:AV0Z70850503 Keywords : transition countries * structural break * volatility Subject RIV: AH - Economics http://deepblue.lib.umich.edu/bitstream/2027.42/41234/1/IPC-working-paper-016-Kocenda.pdf 10. To Break it Down or Not Break it Down: That is the Question! Science.gov (United States) Coker, Cheryl A. 2006-01-01 Learning a new skill, even a seemingly simple one, can be an overwhelming task for a beginner. A question often faced by the practitioner as a result is whether or not to break the skill into parts for initial practice. Skill complexity and skill organization interact to provide direction as to whether whole or part practice should be employed in… 11. Topically applied connective tissue growth factor/CCN2 improves diabetic preclinical cutaneous wound healing: potential role for CTGF in human diabetic foot ulcer healing. Science.gov (United States) Henshaw, F R; Boughton, P; Lo, L; McLennan, S V; Twigg, S M 2015-01-01 Topical application of CTGF/CCN2 to rodent diabetic and control wounds was examined. In parallel research, correlation of CTGF wound fluid levels with healing rate in human diabetic foot ulcers was undertaken. Full thickness cutaneous wounds in diabetic and nondiabetic control rats were treated topically with 1 μg rhCTGF or vehicle alone, on 2 consecutive days. Wound healing rate was observed on day 14 and wound sites were examined for breaking strength and granulation tissue. In the human study across 32 subjects, serial CTGF regulation was analyzed longitudinally in postdebridement diabetic wound fluid. CTGF treated diabetic wounds had an accelerated closure rate compared with vehicle treated diabetic wounds. Healed skin withstood more strain before breaking in CTGF treated rat wounds. Granulation tissue from CTGF treatment in diabetic wounds showed collagen IV accumulation compared with nondiabetic animals. Wound α-smooth muscle actin was increased in CTGF treated diabetic wounds compared with untreated diabetic wounds, as was macrophage infiltration. Endogenous wound fluid CTGF protein rate of increase in human diabetic foot ulcers correlated positively with foot ulcer healing rate (r = 0.406; P diabetic foot ulcers. 12. Compressive and flexural strength of high strength phase change mortar Science.gov (United States) Qiao, Qingyao; Fang, Changle 2018-04-01 High-strength cement produces a lot of hydration heat when hydrated, it will usually lead to thermal cracks. Phase change materials (PCM) are very potential thermal storage materials. Utilize PCM can help reduce the hydration heat. Research shows that apply suitable amount of PCM has a significant effect on improving the compressive strength of cement mortar, and can also improve the flexural strength to some extent. 13. Institutional Strength in Depth International Nuclear Information System (INIS) Weightman, M. 2016-01-01 Much work has been undertaken in order to identify, learn and implement the lessons from the TEPCO Fukushima Daiichi nuclear accident. These have mainly targeted on engineering or operational lessons. Less attention has been paid to the institutional lessons, although there have been some measures to improve individual peer reviews, particularly by the World Association of Nuclear Operators, and the authoritative IAEA report published in 2015 brought forward several important lessons for regulators and advocated a system approach. The report noted that one of the contributing factors the accident was the tendency of stakeholders not to challenge. Additionally, it reported deficiencies in the regulatory authority and system. Earlier, the root cause of the accident was identified by a Japanese independent parliamentary report as being cultural and institutional. The sum total of the institutions, the safety system, was ineffective. While it is important to address the many technical and operational lessons these may not necessary address this more fundamental lesson, and may not serve to provide robust defences against human or institutional failings over a wide variety of possible events and combinations. The overall lesson is that we can have rigorous and comprehensive safety standards and other tools in place to deliver high levels of safety, but ultimately what is important is the ability of the nuclear safety system to ensure that the relevant institutions diligently and effectively apply those standards and tools — to be robust and resilient. This has led to the consideration of applying the principles of the strength in depth philosophy to a nuclear safety system as a way of providing a framework for developing, assessing, reviewing and improving the system. At an IAEA conference in October 2013, a model was presented for a robust national nuclear safety system based on strength in depth philosophy. The model highlighted three main layers: industry, the 14. Symmetry Breaking in MILP Formulations for Unit Commitment Problems KAUST Repository Lima, Ricardo 2015-12-11 This paper addresses the study of symmetry in Unit Commitment (UC) problems solved by Mixed Integer Linear Programming (MILP) formulations, and using Linear Programming based Branch & Bound MILP solvers. We propose three sets of symmetry breaking constraints for UC MILP formulations exhibiting symmetry, and its impact on three UC MILP models are studied. The case studies involve the solution of 24 instances by three widely used models in the literature, with and without symmetry breaking constraints. The results show that problems that could not be solved to optimality within hours can be solved with a relatively small computational burden if the symmetry breaking constraints are assumed. The proposed symmetry breaking constraints are also compared with the symmetry breaking methods included in two MILP solvers, and the symmetry breaking constraints derived in this work have a distinct advantage over the methods in the MILP solvers. 15. Chiral symmetry breaking and confinement - solutions of relativistic wave equations International Nuclear Information System (INIS) Murugesan, P. 1983-01-01 In this thesis, an attempt is made to explore the question whether confinement automatically leads to chiral symmetry breaking. While it should be accepted that chiral symmetry breaking manifests in nature in the absence of scalar partners of pseudoscalar mesons, it does not necessarily follow that confinement should lead to chiral symmetry breaking. If chiral conserving forces give rise to observed spectrum of hadrons, then the conjuncture that confinement is responsible for chiral symmetry breaking is not valid. The method employed to answer the question whether confinement leads to chiral symmetry breaking or not is to solve relativistic wave equations by introducing chiral conserving as well as chiral breaking confining potentials and compare the results with experimental observations. It is concluded that even though chiral symmetry is broken in nature, confinement of quarks need not be the cause of it 16. Symmetry Breaking in MILP Formulations for Unit Commitment Problems KAUST Repository Lima, Ricardo; Novais, Augusto Q. 2015-01-01 This paper addresses the study of symmetry in Unit Commitment (UC) problems solved by Mixed Integer Linear Programming (MILP) formulations, and using Linear Programming based Branch & Bound MILP solvers. We propose three sets of symmetry breaking constraints for UC MILP formulations exhibiting symmetry, and its impact on three UC MILP models are studied. The case studies involve the solution of 24 instances by three widely used models in the literature, with and without symmetry breaking constraints. The results show that problems that could not be solved to optimality within hours can be solved with a relatively small computational burden if the symmetry breaking constraints are assumed. The proposed symmetry breaking constraints are also compared with the symmetry breaking methods included in two MILP solvers, and the symmetry breaking constraints derived in this work have a distinct advantage over the methods in the MILP solvers. 17. PWR cold-leg small break loca with faulty HPI International Nuclear Information System (INIS) Kumamaru, H.; Kukita, Y. 1991-01-01 The ROSA-IV Large Scale Test Facility (LSTF) is a 1/48 volumetrically-scaled model of a pressurized water reactor (PWR). At the LSTF are performed cold-leg small-break loss-of-coolant accident (LOCA) tests with faulty high pressure injection (HPI) system for break areas from 0.5% to 10% and an intentional primary system depressurization test following a small-break LOCA test. A simple prediction model is proposed for prediction of times of major events. Test data and calculations show that intentional primary system depressurization with use of the pressurizer power-operated relief valves (PORVs) is effective for break areas of approximately 0.5% or less, is unnecessary for breaks of 5% or more, and is insufficient for intermediate break areas to maintain adequate core cooling. (author) 18. Napping during breaks on night shift: critical care nurse managers' perceptions. Science.gov (United States) Edwards, Marie P; McMillan, Diana E; Fallis, Wendy M 2013-01-01 Fatigue associated with shiftwork can threaten the safety and health of nurses and the patients in their care. Napping during night shift breaks has been shown to be an effective strategy to decrease fatigue and enhance performance in a variety of work environments, but appears to have mixed support within health care. The purpose of this study was to explore critical care unit managers'perceptions of and experiences with their nursing staff's napping practices on night shift, including their perceptions of the benefits and barriers to napping/not napping in terms of patient safety and nurses'personal health and safety. A survey design was used. Forty-seven Canadian critical care unit managers who were members of the Canadian Association of Critical Care Nurses responded to the web-based survey. Data analysis involved calculation of frequencies and percentages for demographic data, use of the Friedman rank test for comparison of managers' perceptions, and content analysis for responses to open-ended questions. The findings of this study offer valuable insights into the complexities and conflicts perceived by managers with respect to napping on night shift breaks by nursing staff Staff and patient health and safety issues, work and break expectations and experiences, and strengths and deficits related to organizational napping resources and policy are considerations that will be instrumental in the development of effective napping strategies and guidelines. 19. Atmospheric Transport and Mixing linked to Rossby Wave Breaking in GFDL Dynamical Core Science.gov (United States) Liu, C.; Barnes, E. A. 2015-12-01 Atmospheric transport and mixing plays an important role in the global energy balance and the distribution of health-related chemical constituents. Previous studies suggest a close linkage between large-scale transport and Rossby wave breaking (RWB). In this work, we use the GFDL spectral dynamical core to investigate this relationship and study the response of RWB-related transport in different climate scenarios. In a standard control run, we quantify the contribution of RWB to the total transport and mixing of an idealized tracer. In addition, we divide the contribution further into the two types of RWB - anticyclonic wave breaking (AWB) and cyclonic wave breaking (CWB) -- and contrast their efficiency at transport and mixing. Our results are compared to a previous study in which the transport ability of the two types of RWB is studied for individual baroclinic wave life-cycles. In a series of sensitivity runs, we study the response of RWB-related transport and mixing to various states of the jet streams. The responses of the mean strength, frequency, and the efficiency of RWB-related transport are documented and the implications for the transport and mixing in a warmer climate are discussed. 20. Mixed Mediation of Supersymmetry Breaking in Models with Anomalous U(1) Gauge Symmetry International Nuclear Information System (INIS) Choi, Kiwoon 2010-01-01 There can be various built-in sources of supersymmetry breaking in models with anomalous U(1) gauge symmetry, e.g. the U(1) D-term, the F-components of the modulus superfield required for the Green-Schwarz anomaly cancellation mechanism and the chiral matter superfields required to cancel the Fayet-Iliopoulos term, and finally the supergravity auxiliary component which can be parameterized by the F-component of chiral compensator. The relative strength between these supersymmetry breaking sources depends crucially on the characteristics of D-flat direction and also on how the D-flat direction is stabilized at a vacuum with nearly vanishing cosmological constant. We examine the possible pattern of the mediation of supersymmetry breaking in models with anomalous U(1) gauge symmetry, and find that various different mixed mediation scenarios can be realized, including the mirage mediation which corresponds to a mixed modulus-anomaly mediation, D-term domination giving a split sparticle spectrum, and also a mixed gauge-D-term mediation scenario. 1. Synthesis of biodegradable and electroactive multiblock polylactide and aniline pentamer copolymer for tissue engineering applications. Science.gov (United States) Huang, Lihong; Zhuang, Xiuli; Hu, Jun; Lang, Le; Zhang, Peibiao; Wang, Yu; Chen, Xuesi; Wei, Yen; Jing, Xiabin 2008-03-01 To obtain one biodegradable and electroactive polymer as the scaffold for tissue engineering, the multiblock copolymer PLAAP was designed and synthesized with the condensation polymerization of hydroxyl-capped poly( l-lactide) (PLA) and carboxyl-capped aniline pentamer (AP). The PLAAP copolymer exhibited excellent electroactivity, solubility, and biodegradability. At the same time, as one scaffold material, PLAAP copolymer possesses certain mechanical properties with the tensile strength of 3 MPa, tensile Young 's modulus of 32 MPa, and breaking elongation rate of 95%. We systematically studied the compatibility of PLAAP copolymer in vitro and proved that the electroactive PLAAP copolymer was innocuous, biocompatible, and helpful for the adhesion and proliferation of rat C6 cells. Moreover, the PLAAP copolymer stimulated by electrical signals was demonstrated as accelerating the differentiation of rat neuronal pheochromocytoma PC-12 cells. This biodegradable and electroactive PLAAP copolymer thus possessed the properties in favor of the long-time application in vivo as nerve repair scaffold materials in tissue engineering. 2. New particles and breaking the colour symmetry International Nuclear Information System (INIS) Krolikowski, W. 1975-01-01 In the framework of one-gluon-exchange static forces mediated by a colour octet or nonet of vector gluons, we discuss quark binding in coloured-meson states and its connection with breaking the colour symmetry. A possible identification of psi (3.1), psi(3.7) and the broad bump at 4.1 GeV with some coloured bound states of quarks and antiquarks is pointed out. This identification implies the existence of a second bump in the region of 5 GeV. The general conclusion of the paper is that the colour interpretation of the new particles may be true only if the colour symmetry is badly broken (provided the considered forces are relevant). (author) 3. Structural breaks and energy efficiency in Fiji International Nuclear Information System (INIS) Bhaskara Rao, B.; Rao, Gyaneshwar 2009-01-01 This paper examines how energy-output ratios (EYRs) in Fiji have responded to the major energy crises and in particular if these ratios have declined after the energy shocks. The expectation is that energy efficiency should improve after an energy crisis. For this purpose we have used at first a few simpler procedures and then a recently developed more powerful tests for structural breaks by Bai and Perron [Bai, J., Perron, P., 1998. Estimating and testing linear models with multiple structural changes. Econometrica 66, 47-78; Bai, J., Perron, P., 2003a. Computation and analysis of multiple structural change models. Journal of Applied Econometrics 18, 1-22; Bai, J., Perron, P., 2003b. Critical values for multiple structural change tests. Econometrics Journal 6, 72-78]. Policy implications of our results are discussed. 4. Passive appendages generate drift through symmetry breaking Science.gov (United States) Lācis, U.; Brosse, N.; Ingremeau, F.; Mazzino, A.; Lundell, F.; Kellay, H.; Bagheri, S. 2014-10-01 Plants and animals use plumes, barbs, tails, feathers, hairs and fins to aid locomotion. Many of these appendages are not actively controlled, instead they have to interact passively with the surrounding fluid to generate motion. Here, we use theory, experiments and numerical simulations to show that an object with a protrusion in a separated flow drifts sideways by exploiting a symmetry-breaking instability similar to the instability of an inverted pendulum. Our model explains why the straight position of an appendage in a fluid flow is unstable and how it stabilizes either to the left or right of the incoming flow direction. It is plausible that organisms with appendages in a separated flow use this newly discovered mechanism for locomotion; examples include the drift of plumed seeds without wind and the passive reorientation of motile animals. 5. Passive appendages aid locomotion through symmetry breaking Science.gov (United States) Bagheri, Shervin; Lacis, Ugis; Mazzino, Andrea; Kellay, Hamid; Brosse, Nicolas; Lundell, Fredrik; Ingremeau, Francois 2014-11-01 Plants and animals use plumes, barbs, tails, feathers, hairs, fins, and other types of appendages to aid locomotion. Despite their enormous variation, passive appendages may contribute to locomotion by exploiting the same physical mechanism. We present a new mechanism that applies to body appendages surrounded by a separated flow, which often develops behind moving bodies larger than a few millimeters. We use theory, experiments, and numerical simulations to show that bodies with protrusions turn and drift by exploiting a symmetry-breaking instability similar to the instability of an inverted pendulum. Our model explains why the straight position of an appendage in flowing fluid is unstable and how it stabilizes either to the left or right of the incoming fluid flow direction. The discovery suggests a new mechanism of locomotion that may be relevant for certain organisms; for example, how plumed seeds may drift without wind and how motile animals may passively reorient themselves. 6. Observing string breaking with Wilson loops CERN Document Server Kratochvila, S; Kratochvila, Slavo; Forcrand, Philippe de 2003-01-01 An uncontroversial observation of adjoint string breaking is proposed, while measuring the static potential from Wilson loops only. The overlap of the Wilson loop with the broken-string state is small, but non-vanishing, so that the broken-string groundstate can be seen if the Wilson loop is long enough. We demonstrate this in the context of the (2+1)d SU(2) adjoint static potential, using an improved version of the Luscher-Weisz exponential variance reduction. To complete the picture we perform the more usual multichannel analysis with two basis states, the unbroken-string state and the broken-string state (two so-called gluelumps). As by-products, we obtain the temperature-dependent static potential measured from Polyakov loop correlations, and the fundamental SU(2) static potential with improved accuracy. Comparing the latter with the adjoint potential, we see clear deviations from Casimir scaling. 7. Dirac gauginos in low scale supersymmetry breaking International Nuclear Information System (INIS) Goodsell, Mark D.; Tziveloglou, Pantelis 2014-01-01 It has been claimed that Dirac gaugino masses are necessary for realistic models of low-scale supersymmetry breaking, and yet very little attention has been paid to the phenomenology of a light gravitino when gauginos have Dirac masses. We begin to address this deficit by investigating the couplings and phenomenology of the gravitino in the effective Lagrangian approach. We pay particular attention to the phenomenology of the scalar octets, where new decay channels open up. This leads us to propose a new simplified effective scenario including only light gluinos, sgluons and gravitinos, allowing the squarks to be heavy – with the possible exception of the third generation. Finally, we comment on the application of our results to Fake Split Supersymmetry 8. A (critical) overview of electroweak symmetry breaking International Nuclear Information System (INIS) Csaki, Csaba 2010-01-01 This presentation discusses the following points: The standard Higgs, big vs. little hierarchy; Electroweak Symmetry Breaking in supersymmetry and little hierarchy of Minimal Supersymmetric Standard Model (MSSM): Buried Higgs, Bigger quartic (D-terms, Next-to-Minimal Supersymmetric Standard Model (NMSSM), fat Higgs,..); Strong dynamics and related models: Technicolor, Monopole condensate, Warped extra dimensions, Realistic RS, Higgs-less, Composite Higgs, Little Higgs. In summary, we do not understand how Higgs is light and still no trace of new physics. In Supersymmetry (SUSY) it calls for extension of MSSM. In strong dynamics models: electroweak penguin (EWP) usually issue (Warped extra dimension - composite Higgs, Higgs-less, Little Higgs, Technicolor, monopole condensation,..). None of them is fully convincing but LHC should settle these 9. Symmetry breaking during seeded growth of nanocrystals. Science.gov (United States) Xia, Xiaohu; Xia, Younan 2012-11-14 Currently, most of the reported noble-metal nanocrystals are limited to a high level of symmetry, as constrained by the inherent, face-centered cubic (fcc) lattice of these metals. In this paper, we report, for the first time, a facile and versatile approach (backed up by a clear mechanistic understanding) for breaking the symmetry of an fcc lattice and thus obtaining nanocrystals with highly unsymmetrical shapes. The key strategy is to induce and direct the growth of nanocrystal seeds into unsymmetrical modes by manipulating the reduction kinetics. With silver as an example, we demonstrated that the diversity of possible shapes taken by noble-metal nanocrystals could be greatly expanded by incorporating a series of new shapes drastically deviated from the fcc lattice. This work provides a new method to investigate shape-controlled synthesis of metal nanocrystal. 10. Symmetry breaking bifurcations of a current sheet International Nuclear Information System (INIS) Parker, R.D.; Dewar, R.L.; Johnson, J.L. 1990-01-01 Using a time evolution code with periodic boundary conditions, the viscoresistive hydromagnetic equations describing an initially static, planar current sheet with large Lundquist number have been evolved for times long enough to reach a steady state. A cosh 2 x resistivity model was used. For long periodicity lengths L p , the resistivity gradient drives flows that cause forced reconnection at X point current sheets. Using L p as a bifurcation parameter, two new symmetry breaking bifurcations were found: a transition to an asymmetric island chain with nonzero, positive, or negative phase velocity, and a transition to a static state with alternating large and small islands. These states are reached after a complex transient behavior, which involves a competition between secondary current sheet instability and coalescence 11. Instantons, monopoles and chiral symmetry breaking International Nuclear Information System (INIS) Feurstein, M.; Markum, H.; Thurner, S. 1996-01-01 We analyze the interplay of topological objects in four dimensional QCD. The distributions of color magnetic monopoles obtained in the maximum abelian gauge are computed around instantons in both pure and full QCD. We find an enhanced probability of encountering monopoles inside the core of an instanton. We show this by means of local correlation functions of the topological variables. For specific gauge field configurations we visualize the situation graphically. Motivated by the fact that a fermion in the field of a static monopole has an energy zero mode we investigate how monopole loops and instantons are locally correlated with the chiral condensate. The observed correlations suggest that monopoles are involved in the mechanism of breaking of chiral symmetry. (orig.) 12. Gravity mediated supersymmetry breaking in six dimensions International Nuclear Information System (INIS) Falkowski, A.; Lee, H.M.; Luedeling, C. 2005-04-01 We study gravity mediated supersymmetry breaking in four-dimensional effective theories derived from six-dimensional brane-world supergravities. Using the Noether method we construct a locally supersymmetric action for a bulk-brane system consisting of the minimal six-dimensional supergravity coupled to vector and chiral multiplets located at four-dimensional branes. We compactify this system on T 2 /Z 2 and derive the four-dimensional effective supergravity. Most interestingly, sequestering of the matter living on different branes is not explicit in the tree-level Kaehler potential (but of course the action obtained from this Kaehler potential is consistent with higher dimensional locality). As a consequence, the features of gravity mediation are different than in five-dimensional models. We identify one scenario of moduli stabilization that yields positive gravity mediated soft scalar masses squared. (orig.) 13. Gravity mediated supersymmetry breaking in six dimensions International Nuclear Information System (INIS) Falkowski, Adam; Lee, Hyun Min; Luedeling, Christoph 2005-01-01 We study gravity mediated supersymmetry breaking in four-dimensional effective theories derived from six-dimensional brane-world supergravity. Using the Noether method we construct a locally supersymmetric action for a bulk-brane system consisting of the minimal six-dimensional supergravity coupled to vector and chiral multiplets located at four-dimensional branes. Couplings of the bulk moduli to the brane are uniquely fixed, in particular, they are flavour universal. We compactify this system on T 2 /Z 2 and derive the four-dimensional effective supergravity. The tree-level effective Kaehler potential is not of the sequestered form, therefore gravity mediation may occur at tree-level. We identify one scenario of moduli stabilization in which the soft scalar masses squared are positive 14. Supersymmetry Breaking, Gauge Mediation, and the LHC International Nuclear Information System (INIS) Shih, David 2015-01-01 Gauge mediated SUSY breaking (GMSB) is a promising class of supersymmetric models that automatically satisfies the precision constraints. Prior work of Meade, Seiberg and Shih in 2008 established the full, model-independent parameter space of GMSB, which they called 'General Gauge Mediation' (GGM). During the first half of 2010-2015, Shih and his collaborators thoroughly explored the parameter space of GGM and established many well-motivated benchmark models for use by the experimentalists at the LHC. Through their work, the current constraints on GGM from LEP, the Tevatron and the LHC were fully elucidated, together with the possible collider signatures of GMSB at the LHC. This ensured that the full discovery potential for GGM could be completely realized at the LHC. 15. Supersymmetry breaking and composite extra dimensions International Nuclear Information System (INIS) Luty, Markus A.; Sundrum, Raman 2002-01-01 We study supergravity models in four dimensions where the hidden sector is superconformal and strongly coupled over several decades of energy below the Planck scale, before undergoing spontaneous breakdown of scale invariance and supersymmetry. We show that large anomalous dimensions can suppress Kaehler contact terms between the hidden and visible sectors, leading to models in which the hidden sector is 'sequestered' and anomaly-mediated supersymmetry breaking can naturally dominate, thus solving the supersymmetric flavor problem. We construct simple, explicit models of the hidden sector based on supersymmetric QCD in the conformal window. The present approach can be usefully interpreted as having an extra dimension responsible for sequestering replaced by the many states of a (spontaneously broken) strongly coupled superconformal hidden sector, as dictated by the anti-de Sitter conformal field theory correspondence 16. Symmetry breaking: The standard model and superstrings International Nuclear Information System (INIS) Gaillard, M.K. 1988-01-01 The outstanding unresolved issue of the highly successful standard model is the origin of electroweak symmetry breaking and of the mechanism that determines its scale, namely the vacuum expectation value (vev)v that is fixed by experiment at the value v = 4m//sub w//sup 2///g 2 = (√2G/sub F/)/sup /minus/1/ ≅ 1/4 TeV. In this talk I will discuss aspects of two approaches to this problem. One approach is straightforward and down to earth: the search for experimental signatures, as discussed previously by Pierre Darriulat. This approach covers the energy scales accessible to future and present laboratory experiments: roughly (10/sup /minus/9/ /minus/ 10 3 )GeV. The second approach involves theoretical speculations, such as technicolor and supersymmetry, that attempt to explain the TeV scale. 23 refs., 5 figs 17. Special small-break applications with TRAC International Nuclear Information System (INIS) Dobranich, D.; DeMuth, N.S.; Henninger, R.J.; Burns, R.D. III. 1981-01-01 Input models for the Transient Reactor Analysis Code (TRAC) are described and applications of these models to reactor transients involving small breaks in the primary coolant pressure boundary are demonstrated. The operation of the primary overpressure protection system (relief and safety valves) and the thermal-hydraulic response of the reactor to these transients are obtained from numerical simulations. Also, the effects of steam generator recirculation, steam generator tube rupture, Emergency Core Cooling (ECC) injection and reactivity feedback on the course and consequences of these transients are investigated. These models allow reliable predictions of accident signatures that can help determine the adequacy of equipment and procedures at nuclear power plants to prevent and to control severe accidents 18. Symmetry breaking bifurcations of a current sheet International Nuclear Information System (INIS) Parker, R.D.; Dewar, R.L.; Johnson, J.L. 1988-08-01 Using a time evolution code with periodic boundary conditions, the viscoresistive hydromagnetic equations describing an initially static, planar current sheet with large Lundquist number have been evolved for times long enough to reach a steady state. A cosh 2 x resistivity model was used. For long periodicity lengths, L p , the resistivity gradient drives flows which cause forced reconnection at X point current sheets. Using L p as a bifurcation parameter, two new symmetry breaking bifurcations were found - a transition to an asymmetric island chain with nonzero, positive or negative phase velocity, and a transition to a static state with alternating large and small islands. These states are reached after a complex transient behavior which involves a competition between secondary current sheet instability and coalescence. 31 refs., 6 figs 19. Applicability of the leak before break concept International Nuclear Information System (INIS) 1993-06-01 Within the framework of the IAEA Extrabudgetary Programme on the Safety of WWER-440 Model 230 NPPs, a list of safety issues requiring broad studies of general interest have been agreed upon by an Advisory Group which met in Vienna in September 1990. The information on the status of the issues, and on amount of work already completed and under way in various countries, needs to be compiled. Moreover, an evaluation of what further work is required to resolve each of the issues is also necessary. In view of this, the IAEA has started the preparation of a series of status reports on the various issues. This report on the generic safety issue ''Applicability of the Leak Before Break Concept'' presents a comprehensive survey of technical information available in the field and identifies those which require further investigation. 50 refs, 15 figs, 2 tabs 20. Towards a Decision Making Model for City Break Travel OpenAIRE Dunne, Gerard; Flanagan, Sheila; Buckley, Joan 2011-01-01 Purpose The purpose of this paper is to examine the city break travel decision and in particular to develop a decision making model that reflects the characteristics of this type of trip taking. Method The research follows a sequential mixed methods approach consisting of two phases. Phase One involves a quantitative survey of 1,000 visitors to Dublin, from which city break and non city break visitor cohorts are separated and compared. Phase Two entails a qualitative analysis (involvin... 1. Breaking Gaussian incompatibility on continuous variable quantum systems Energy Technology Data Exchange (ETDEWEB) Heinosaari, Teiko, E-mail: teiko.heinosaari@utu.fi [Turku Centre for Quantum Physics, Department of Physics and Astronomy, University of Turku, FI-20014 Turku (Finland); Kiukas, Jukka, E-mail: jukka.kiukas@aber.ac.uk [Department of Mathematics, Aberystwyth University, Penglais, Aberystwyth, SY23 3BZ (United Kingdom); Schultz, Jussi, E-mail: jussi.schultz@gmail.com [Turku Centre for Quantum Physics, Department of Physics and Astronomy, University of Turku, FI-20014 Turku (Finland); Dipartimento di Matematica, Politecnico di Milano, Piazza Leonardo da Vinci 32, I-20133 Milano (Italy) 2015-08-15 We characterise Gaussian quantum channels that are Gaussian incompatibility breaking, that is, transform every set of Gaussian measurements into a set obtainable from a joint Gaussian observable via Gaussian postprocessing. Such channels represent local noise which renders measurements useless for Gaussian EPR-steering, providing the appropriate generalisation of entanglement breaking channels for this scenario. Understanding the structure of Gaussian incompatibility breaking channels contributes to the resource theory of noisy continuous variable quantum information protocols. 2. Review on research of small break loss of coolant accident International Nuclear Information System (INIS) Bo Jinhai; Wang Fei 1998-01-01 The Small Break Loss of Coolant Accident (SBLOCA) and its research art-of -work are reviewed. A typical SBLOCA process in Pressurized Water Reactor (PWR) and Boiling Water Reactor (BWR) and the influence of break size, break location and reactor coolant pump on the process are described. The existing papers are classified in two categories: experimental and numerical modeling, with the primary experimental apparatuses in the world listed and the research works on SBLOCA summarized 3. Phenomenology of induced electroweak symmetry breaking International Nuclear Information System (INIS) Chang, Spencer; Galloway, Jamison; Luty, Markus A.; Salvioni, Ennio; Tsai, Yuhsin 2015-01-01 We study the phenomenology of models of electroweak symmetry breaking where the Higgs potential is destabilized by a tadpole arising from the coupling to an “auxiliary” Higgs sector. The auxiliary Higgs sector can be either perturbative or strongly coupled, similar to technicolor models. Since electroweak symmetry breaking is driven by a tadpole, the cubic and quartic Higgs couplings can naturally be significantly smaller than their values in the standard model. The theoretical motivation for these models is that they can explain the 125 GeV Higgs mass in supersymmetry without fine-tuning. The auxiliary Higgs sector contains additional Higgs states that cannot decouple from standard model particles, so these models predict a rich phenomenology of Higgs physics beyond the standard model. In this paper we analyze a large number of direct and indirect constraints on these models. We present the current constraints after the 8 TeV run of the LHC, and give projections for the sensitivity of the upcoming 14 TeV run. We find that the strongest constraints come from the direct searches A 0 →Zh, A 0 →tt-bar, with weaker constraints from Higgs coupling fits. For strongly-coupled models, additional constraints come from ρ + →WZ where ρ + is a vector resonance. Our overall conclusion is that a significant parameter space for such models is currently open, allowing values of the Higgs cubic coupling down to 0.4 times the standard model value for weakly coupled models and vanishing cubic coupling for strongly coupled models. The upcoming 14 TeV run of the LHC will stringently test this scenario and we identify several new searches with discovery potential for this class of models. 4. Soft-tissue tension total knee arthroplasty. Science.gov (United States) Asano, Hiroshi; Hoshino, Akiho; Wilton, Tim J 2004-08-01 It is far from clear how best to define the proper strength of soft-tissue tensioning in total knee arthroplasty (TKA). We attached a torque driver to the Monogram balancer/tensor device and measured soft-tissue tension in full extension and 90 degrees flexion during TKA. In our surgical procedure, when we felt proper soft-tissue tension was being applied, the mean distraction force was noted to be 126N in extension and 121N in flexion. There was no significant correlation between soft-tissue tension and the postoperative flexion angle finally achieved. To the best of our knowledge, this is the first study to assess the actual distraction forces in relation to soft-tissue tension in TKA. Further study may reveal the most appropriate forces to achieve proper soft-tissue tension in the wide variety of circumstances presenting at knee arthroplasty. 5. Line-breaking algorithm enhancement in inverse typesetting paradigma Directory of Open Access Journals (Sweden) Jan Přichystal 2007-01-01 Full Text Available High quality text preparing using computer desktop publishing systems usually uses line-breaking algorithm which cannot make provision for line heights and typeset paragraph accurately when composition width, page break, line index or other object appears. This article deals with enhancing of line-breaking algorithm based on optimum-fit algorithm. This algorithm is enhanced with calculation of immediate typesetting width and thus solves problem of forced change. Line-breaking algorithm enhancement causes expansion potentialities of high-quality typesetting in cases that have not been yet covered with present typesetting systems. 6. Unstable volatility functions: the break preserving local linear estimator DEFF Research Database (Denmark) Casas, Isabel; Gijbels, Irene The objective of this paper is to introduce the break preserving local linear (BPLL) estimator for the estimation of unstable volatility functions. Breaks in the structure of the conditional mean and/or the volatility functions are common in Finance. Markov switching models (Hamilton, 1989......) and threshold models (Lin and Terasvirta, 1994) are amongst the most popular models to describe the behaviour of data with structural breaks. The local linear (LL) estimator is not consistent at points where the volatility function has a break and it may even report negative values for finite samples... 7. Nonstandard Supersymmetry Breaking and Dirac Gaugino Masses without Supersoftness Energy Technology Data Exchange (ETDEWEB) Martin, Stephen P. [Northern Illinois U. 2015-08-05 I consider models in which nonstandard supersymmetry-breaking terms, including Dirac gaugino masses, arise from F-term breaking mediated by operators with a 1/M3 suppression. In these models, the supersoft properties found in the case of D-term breaking are absent in general, but can be obtained as a special case that is a fixed point of the renormalization group equations. The μ term is replaced by three distinct supersymmetry-breaking parameters, decoupling the Higgs scalar potential from the Higgsino masses. Both holomorphic and nonholomorphic scalar cubic interactions with minimal flavor violation are induced in the supersymmetric Standard Model Lagrangian. 8. Chitosan adhesive for laser tissue repair Science.gov (United States) Lauto, A.; Stoodley, M.; Avolio, A.; Foster, L. J. R. 2006-02-01 Background. Laser tissue repair usually relies on haemoderivate solders, based on serum albumin. These solders have intrinsic limitations that impair their widespread use, such as limited repair strength, high solubility, brittleness and viral transmission. Furthermore, the solder activation temperature (65-70 °C) can induce significant damage to tissue. In this study, a new laser-activated biomaterial for tissue repair was developed and tested in vitro and in vivo to overcome some of the shortcomings of traditional solders. Materials and Methods. Flexible and insoluble strips of chitosan adhesive (surface area ~34 mm2, thickness ~20 μm) were developed and bonded on sheep intestine with a laser fluence and irradiance of 52 +/- 2 J/cm2 and ~15 W/cm2 respectively. The temperature between tissue and adhesive was measured using small thermocouples. The strength of repaired tissue was tested by a calibrated tensiometer. The adhesive was also bonded in vivo to the sciatic nerve of rats to assess the thermal damage induced by the laser (fluence = 65 +/- 11 J/cm2, irradiance = 15 W/cm2) four days post-operatively. Results. Chitosan adhesives successfully repaired intestine tissue, achieving a repair strength of 0.50 +/- 0.15 N (shear stress = 14.7 +/- 4.7 KPa, n=30) at a temperature of 60-65 °C. The laser caused demyelination of axons at the operated site; nevertheless, the myelinated axons retained their normal morphology proximally and distally. 9. Breaking Terrorists’ Will To Fight Science.gov (United States) 2014-06-01 guillotine spreads in all of France and brings to justice all the traitors. There is no other means to inspire the...the end, we shall fight in France , we shall fight on the seas and oceans, we shall fight with growing confidence and growing strength in the air, we...deprivation: “Any ideology—even the very best, even Marxism -Leninism itself—is ineffective unless it is linked with objective realities, meets 10. Spontaneous symmetry breaking and response functions International Nuclear Information System (INIS) Beraudo, A.; De Pace, A.; Martini, M.; Molinari, A. 2005-01-01 We study the quantum phase transition occurring in an infinite homogeneous system of spin 1/2 fermions in a non-relativistic context. As an example we consider neutrons interacting through a simple spin-spin Heisenberg force. The two critical values of the coupling strength-signaling the onset into the system of a finite magnetization and of the total magnetization, respectively-are found and their dependence upon the range of the interaction is explored. The spin response function of the system in the region where the spin-rotational symmetry is spontaneously broken is also studied. For a ferromagnetic interaction the spin response along the direction of the spontaneous magnetization occurs in the particle-hole continuum and displays, for not too large momentum transfers, two distinct peaks. The response along the direction orthogonal to the spontaneous magnetization displays instead, beyond a softened and depleted particle-hole continuum, a collective mode to be identified with a Goldstone boson of type II. Notably, the random phase approximation on a Hartree-Fock basis accounts for it, in particular for its quadratic-close to the origin-dispersion relation. It is shown that the Goldstone boson contributes to the saturation of the energy-weighted sum rule for ∼25% when the system becomes fully magnetized (that is in correspondence of the upper critical value of the interaction strength) and continues to grow as the interaction strength increases 11. The assessment of cold atmospheric plasma treatment of DNA in synthetic models of tissue fluid, tissue and cells Science.gov (United States) Szili, Endre J.; Gaur, Nishtha; Hong, Sung-Ha; Kurita, Hirofumi; Oh, Jun-Seok; Ito, Masafumi; Mizuno, Akira; Hatta, Akimitsu; Cowin, Allison J.; Graves, David B.; Short, Robert D. 2017-07-01 There is a growing literature database that demonstrates the therapeutic potential of cold atmospheric plasma (herein referred to as plasma). Given the breadth of proposed applications (e.g. from teeth whitening to cancer therapy) and vast gamut of plasma devices being researched, it is timely to consider plasma interactions with specific components of the cell in more detail. Plasma can produce highly reactive oxygen and nitrogen species (RONS) such as the hydroxyl radical (OH•), peroxynitrite (ONOO-) and superoxide (\\text{O}2- ) that would readily modify essential biomolecules such as DNA. These modifications could in principle drive a wide range of biological processes. Against this possibility, the reported therapeutic action of plasmas are not underpinned by a particularly deep knowledge of the potential plasma-tissue, -cell or -biomolecule interactions. In this study, we aim to partly address this issue by developing simple models to study plasma interactions with DNA, in the form of DNA-strand breaks. This is carried out using synthetic models of tissue fluid, tissue and cells. We argue that this approach makes experimentation simpler, more cost-effective and faster than compared to working with real biological materials and cells. Herein, a helium plasma jet source was utilised for these experiments. We show that the plasma jet readily induced DNA-strand breaks in the tissue fluid model and in the cell model, surprisingly without any significant poration or rupture of the phospholipid membrane. In the plasma jet treatment of the tissue model, DNA-strand breaks were detected in the tissue mass after pro-longed treatment (on the time-scale of minutes) with no DNA-strand breaks being detected in the tissue fluid model underneath the tissue model. These data are discussed in the context of the therapeutic potential of plasma. 12. A critical Examination of the Phenomenon of Bonding Area - Bonding Strength Interplay in Powder Tableting. Science.gov (United States) Osei-Yeboah, Frederick; Chang, Shao-Yu; Sun, Changquan Calvin 2016-05-01 Although the bonding area (BA) and bonding strength (BS) interplay is used to explain complex tableting behaviors, it has never been experimentally proven. The purpose of this study is to unambiguously establish the distinct contributions of each by decoupling the contributions from BA and BS. To modulate BA, a Soluplus® powder was compressed into tablets at different temperatures and then broken following equilibration at 25°C. To modulate BS, tablets were equilibrated at different temperatures. To simultaneously modulate BA and BS, both powder compression and tablet breaking test were carried out at different temperatures. Lower tablet tensile strength is observed when the powder is compressed at a lower temperature but broken at 25°C. This is consistent with the increased resistance to polymer deformation at lower temperatures. When equilibrated at different temperatures, the tensile strength of tablets prepared under identical conditions increases with decreasing storage temperature, indicating that BS is higher at a lower temperature. When powder compression and tablet breaking are carried out at the same temperature, the profile with a maximum tensile strength at 4°C is observed due to the BA-BS interplay. By systematically varying temperature during tablet compression and breaking, we have experimentally demonstrated the phenomenon of BA-BS interplay in tableting. 13. Breaking sod or breaking even? Flax on the northern Great Plains and Prairies, 1889-1930. Science.gov (United States) MacFayden, Joshua D 2009-01-01 A new thirst for paint and color in cities made extensive flax production profitable in the northern Great Plains and Prairies and contributed to the cultivation of the most fragile grassland ecosystems. The production of flax seed for linseed oil became an early spin-off of the Prairie wheat economy but, unlike wheat, flax vanished from old land after one or two rotations and reappeared in districts with the most new breaking. Officials explained the migrant crop as preparing native grasslands for cultivation or exhausting soil in old land, but farmers brought flax to their new breaking for other reasons. Producers would only put flax on any land when a range of economic and environmental conditions were in place. It was never sown without promise of adequately high prices or in the absence of affordable seed and other inputs. When price allowed, it usually appeared on new breaking because it could be planted later and transported further without upsetting the balance of other activities and without farmers learning many new techniques. Scientists discovered that diseased soil drove flax off old land, not soil exhaustion. Circumventing the disease was possible but costly, and farmers simply replaced flax with the next most lucrative commodity. 14. Skills Associated with Line Breaks in Elite Rugby Union Directory of Open Access Journals (Sweden) Steve den Hollander, James Brown, Michael Lambert, Paul Treu, Sharief Hendricks 2016-09-01 Full Text Available The ability of the attacking team to break through the defensive line is a key indicator of success as it creates opportunities to score tries. The aim of this study was to analyse line breaks and identify the associated skills and playing characteristics. The 2013 Super Rugby season (125 games was analysed, in which 362 line breaks were identified and coded using variables that assessed team patterns and non-contact attacking skills in the phases preceding the line break. There was an average of 3 line breaks per game, with 39% of line breaks resulting in a try. Line breaks occurred when the ball-carrier was running fast [61%, x2(4 = 25.784, p = 0.000, Cramer’s v = 0.1922, weak]. At a moderate distance, short lateral passes (19% and skip passes (15% attributed to the highest percentage of line breaks [x2(26 = 50.899, p = 0.036, Cramer’s v = 0.2484, moderate]. Faster defensive line speeds resulted in more line breaks [x2(12 = 61.703, p < 0.001, Cramer’s v = 0.3026, moderate]. Line breaks are associated with overall team success and try scoring opportunities. Awareness of the defenders line speed and depth, fast running speed when receiving the ball and quick passing between attackers to the outside backs creates line break opportunities. During training, coaches should emphasise the movement speed of the ball between attackers and manipulate the speed and distance of the defenders. 15. Loading Conditions and Longitudinal Strength DEFF Research Database (Denmark) Sørensen, Herman 1995-01-01 Methods for the calculation of the lightweight of the ship.Loading conditions satisfying draught, trim and intact stability requirements and analysis of the corresponding stillwater longitudinal strength.......Methods for the calculation of the lightweight of the ship.Loading conditions satisfying draught, trim and intact stability requirements and analysis of the corresponding stillwater longitudinal strength.... 16. Oscillator strengths for neutral technetium International Nuclear Information System (INIS) Garstang, R.H. 1981-01-01 Oscillator strengths have been calculated for most of the spectral lines of TcI which are of interest in the study of stars of spectral type S. Oscillator strengths have been computed for the corresponding transitions in MnI as a partial check of the technetium calculations 17. Leak-Before-Break assessment of a welded piping based on 3D finite element method International Nuclear Information System (INIS) Chen, Mingya; Yu, Weiwei; Chen, Zhilin; Qian, Guian; Lu, Feng; Xue, Fei 2017-01-01 Highlights: • The effects of load reduction, strength match, welding width, load level, crack size and constraint are studied. • The results show that the LBB margin is dependent on the load level. • The results show that higher strength-match of WPJs will have higher crack-front constraints. • The results show that the engineering method has a high precision only if the width of weld is comparable to the crack depth. - Abstract: The paper studies the effects of the load reduction (discrepancy between designing and real loadings), strength match of the welded piping joint (WPJ), welding width, crack size and crack tip constraint on the Leak-Before-Break (LBB) assessment of a welded piping. The 3D finite element (FE) method is used in the study of a surge line of the steam generator in a nuclear power plant. It is demonstrated that the LBB margin is dependent on the loading level and the load reduction effect should be considered. When the loading is high enough, there is a quite large deviation between the J-integral calculated based on the real material property of WPJ and that calculated based on the engineering method, e.g. Zahoor handbook of Electric Power Research Institute (EPRI). The engineering method assumes that the whole piping is made of the unique welding material in the calculation. As the influence of the strength matching and welding width is ignored in the engineering method for J-integral calculation, the engineering method has a sufficient precision only if the width of welding is comparable to the crack depth. Narrower welding width leads to higher constraint of the plastic deformation in the welding and larger high stress areas in the base for the low strength-match WPJ. Higher strength matching of WPJs has higher crack-front constraints. 18. STRENGTH OF NANOMODIFIED HIGH-STRENGTH LIGHTWEIGHT CONCRETES Directory of Open Access Journals (Sweden) NOZEMTСEV Alexandr Sergeevich 2013-02-01 Full Text Available The paper presents the results of research aimed at development of nanomodified high-strength lightweight concrete for construction. The developed concretes are of low average density and high ultimate compressive strength. It is shown that to produce this type of concrete one need to use hollow glass and aluminosilicate microspheres. To increase the durability of adhesion between cement stone and fine filler the authors offer to use complex nanodimensinal modifier based on iron hydroxide sol and silica sol as a surface nanomodifier for hollow microspheres. It is hypothesized that the proposed modifier has complex effect on the activity of the cement hydration and, at the same time increases bond strength between filler and cement-mineral matrix. The compositions for energy-efficient nanomodified high-strength lightweight concrete which density is 1300…1500 kg/m³ and compressive strength is 40…65 MPa have been developed. The approaches to the design of high-strength lightweight concrete with density of less than 2000 kg/m³ are formulated. It is noted that the proposed concretes possess dense homogeneous structure and moderate mobility. Thus, they allow processing by vibration during production. The economic and practical implications for realization of high-strength lightweight concrete in industrial production have been justified. 19. Repair of double-strand breaks in Micrococcus radiodurans International Nuclear Information System (INIS) Burrell, A.D.; Dean, C.J. 1975-01-01 Micrococcus radiodurans has been shown to sustain double-strand breaks in its DNA after exposure to x-radiation. Following sublethal doses of x-rays (200 krad in oxygen or less), the cells were able to repair these breaks, and an intermediate fast-sedimenting DNA component seemed to be involved in the repair process 20. Chiral symmetry breaking in QED for weak coupling Energy Technology Data Exchange (ETDEWEB) Huang, J.C. (Missouri Univ., Columbia, MO (USA). Dept. of Physics and Astronomy); Shen, T.C. (Illinois Univ., Urbana, IL (USA). Beckman Inst.) 1991-05-01 We examine the procedure for studying chiral symmetry breaking for weak coupling in QED. We note that while the lowest non-trivial order calculations using numerical solutions to the Schwinger-Dyson equation indicate a breaking of chiral symmetry, the neglected higher-order contributions to the effective potential have imaginary values which can indicate possible instabilities in the theory. (author). 1. Chiral symmetry breaking in QED for weak coupling International Nuclear Information System (INIS) Huang, J.C.; Shen, T.C. 1991-01-01 We examine the procedure for studying chiral symmetry breaking for weak coupling in QED. We note that while the lowest non-trivial order calculations using numerical solutions to the Schwinger-Dyson equation indicate a breaking of chiral symmetry, the neglected higher-order contributions to the effective potential have imaginary values which can indicate possible instabilities in the theory. (author) 2. Gauge principle, vector-meson dominance, and spontaneous symmetry breaking International Nuclear Information System (INIS) Nambu, Yoichiro 1989-01-01 The author concentrates on certain theoretical developments of the late 1950s which are concerned with the meaning and role of symmetries and symmetry breaking, and especially work done in Chicago, and notes his own involvement in this debate. He worked on symmetry-breaking in superconductivity, using a four-fermion interaction model. (UK) 3. Spontaneous breaking of supersymmetry and gauge invariance in supergravity Energy Technology Data Exchange (ETDEWEB) Sohnius, M. (European Organization for Nuclear Research, Geneva (Switzerland)); West, P. (King' s Coll., London (UK). Dept. of Mathematics) 1982-08-09 Using the new minimal auxillary fields of N = 1 supergravity it is found possible to construct a model of local supersymmetry which spontaneously breaks both supersymmetry and gauge invariance. The status of the cosmological constant resulting from this breaking is discussed. 4. Spontaneous breaking of supersymmetry and gauge invariance in supergravity International Nuclear Information System (INIS) Sohnius, M.; West, P. 1982-01-01 Using the new minimal auxillary fields of N = 1 supergravity it is found possible to construct a model of local supersymmetry which spontaneously breaks both supersymmetry and gauge invariance. The status of the cosmological constant resulting from this breaking is discussed. (orig.) 5. Physical pictures of symmetry breaking in quenched QED4 International Nuclear Information System (INIS) Kogut, J.B.; Argonne National Lab., IL 1989-01-01 We discuss 'collapse of the wavefunction' as the phenomenon underlying chiral symmetry breaking in quenched QED4. The 1/r singularity in the 'collapsed' qanti q wavefunction causes 'catalyzed symmetry breaking' which is the field theoretic analog of 'monopole induced proton decay'. The evasion of mean field exponents by the quenched theory's chiral phase transition is emphasized. (orig.) 6. Evaluation of ATLAS 100% DVI Line Break Using TRACE Code International Nuclear Information System (INIS) Huh, Byung Gil; Bang, Young Seok; Cheong, Ae Ju; Woo, Sweng Woong 2011-01-01 ATLAS (Advanced Thermal-Hydraulic Test Loop for Accident Simulation) is an integral effect test facility in KAERI. It had installed completely to simulate the accident for the OPR1000 and the APR1400 in 2005. After then, several tests for LBLOCA, DVI line break have been performed successfully to resolve the safety issues of the APR1400. Especially, a DVI line break is considered as another spectrum among the SBLOCAs in APR1400 because the DVI line is directly connected to the reactor vessel and the thermal hydraulic behaviors are expected to be different from those for the cold leg injection. However, there are not enough experimental data for the DVI line break. Therefore, integral effect data for the DVI line break of ATLAS is very useful and available for an improvement and validation of safety codes. For the DVI line break in ATLAS, several analyses using MARS and RELAP codes were performed in the ATLAS DSP (Domestic Standard Problem) meetings. However, TRACE code has still not used to simulate a DVI line break. TRACE code has developed as the unified code for the reactor thermal hydraulic analyses in USNRC. In this study, the 100% DVI line break in ATLAS was evaluated by TRACE code. The objectives of this study are to identify the prediction capability of TRACE code for the major thermal hydraulic phenomena of a DVI line break in ATLAS 7. Some geological and geophysical aspects in electric rock breaking CSIR Research Space (South Africa) Henry, G 2011-08-01 Full Text Available an important role in any rock-breaking techniques using electrical power. The research done at the CSIR's Centre for Mining Innovation is towards understanding the science behind electric rock breaking. This understanding would lead to a practical method... 8. Dynamics of symmetry breaking in strongly coupled QED International Nuclear Information System (INIS) Bardeen, W.A. 1988-10-01 I review the dynamical structure of strong coupled QED in the quenched planar limit. The symmetry structure of this theory is examined with reference to the nature of both chiral and scale symmetry breaking. The renormalization structure of the strong coupled phase is analysed. The compatibility of spontaneous scale and chiral symmetry breaking is studied using effective lagrangian methods. 14 refs., 3 figs 9. Chiral symmetry breaking and cooling in lattice QCD International Nuclear Information System (INIS) Woloshyn, R.M.; Lee, F.X. 1995-08-01 Chiral symmetry breaking is calculated as a function of cooling in quenched lattice QCD. A non-zero signal is found for the chiral condensate beyond one hundred cooling steps, suggesting that there is chiral symmetry breaking associated with instantons. Quantitatively, the chiral condensate in cooled gauge field configurations is small compared to the value without cooling. (author) 7 refs., 1 tab., 3 figs 10. An automatic system for elaboration of chip breaking diagrams DEFF Research Database (Denmark) Andreasen, Jan Lasson; De Chiffre, Leonardo 1998-01-01 A laboratory system for fully automatic elaboration of chip breaking diagrams has been developed and tested. The system is based on automatic chip breaking detection by frequency analysis of cutting forces in connection with programming of a CNC-lathe to scan different feeds, speeds and cutting... 11. Breaking the spores of Ganoderma lucidum by fermentation with ... African Journals Online (AJOL) In this paper, fermentation of G. lucidum with Lactobacillus plantarum was applied to break down the sporoderm. Scanning electron microscope (SEM) was used to characterize the spores. The broken spores were found on the 3rd day and complete breaking on the 5th day of fermentation. Lactic acid, acetic acid and ... 12. Salam-Weinberg symmetry breaking with superheavy Higgs particles International Nuclear Information System (INIS) Misra, S.P. 1986-09-01 We discuss here the possibility of the breaking of the Salam-Weinberg symmetry by Higgs particles which are superheavy. The symmetry-breaking is associated with a nonzero vacuum expectation value of fermion condensates. This mechanism, if operative in nature, will imply the absence of Higgs particles at the weak scale. (author) 13. View of industry on the impact of pipe break criteria International Nuclear Information System (INIS) Bernsen, S.A. 1983-01-01 Historically, large pipe breaks in the types of materials used and under operating conditions similar to those in light water reactor service have not occurred. Nevertheless, the non-mechanistic assumption of a double ended pipe break of the early sixties, selected for loss of coolant accident analysis purposes, has become a mechanistic criterion for the design and arrangement of high pressure piping systems and their associated supports and enclosures in today's nuclear plants. While it seems reasonable and appropriate to continue to design the Emergency Core Cooling Systems for a range of loss of coolant accidents up to and including those that approximate the area of the largest pipe connected to the reactor vessel and to use this break in determining the loading and temperature rise rate for containment structures and equipment qualification, it no longer seems reasonable to provide precisely engineered break protection for a limited number of potential pipe break locations. This observation is gaining increasing support, particularly as engineering judgment and historical perspectives are being supplemented by both deterministic and probabilistic studies that indicate the potential for large instantaneous breaks in nuclear grade piping systems is virtually incredible. Fracture mechanics analyses support leak-before-break assumptions with wide margins and probabilistic studies indicate potentials for double-ended pipe breaks in the range of less than one in a billion years 14. Supergravity and upper bound on scale of supersymmetry breaking International Nuclear Information System (INIS) Kim, J.E.; Nishino, H. 1983-09-01 In locally supersymmetric grand unified models we show rather a model independent upper bound 3x10 11 GeV for the scale of supersymmetry breaking, which is derived by considering SU(2)xU(1) breaking at electro-weak mass scale. This bound necessarily implies the existence of new particles (superpartners) below 10 4 GeV. (author) 15. Electroweak symmetry breaking in supersymmetric gauge-Higgs unification models International Nuclear Information System (INIS) Choi, Kiwoon; Jeong, Kwang-Sik; Okumura, Ken-ichi; Haba, Naoyuki; Shimizu, Yasuhiro; Yamaguchi, Masahiro 2004-01-01 We examine the Higgs mass parameters and electroweak symmetry breaking in supersymmetric orbifold field theories in which the 4-dimensional Higgs fields originate from higher-dimensional gauge supermultiplets. It is noted that such gauge-Higgs unification leads to a specific boundary condition on the Higgs mass parameters at the compactification scale, which is independent of the details of supersymmetry breaking mechanism. With this boundary condition, phenomenologically viable parameter space of the model is severely constrained by the condition of electroweak symmetry breaking for supersymmetry breaking scenarios which can be realized naturally in orbifold field theories. For instance, if it is assumed that the 4-dimensional effective theory is the minimal supersymmetric standard model with supersymmetry breaking parameters induced by the Scherk-Schwarz mechanism, a correct electroweak symmetry breaking can not be achieved for reasonable range of parameters of the model, even when one includes additional contributions to the Higgs mass parameters from the auxiliary component of 4-dimensional conformal compensator. However if there exists a supersymmetry breaking mediated by brane superfields, sizable portion of the parameter space can give a correct electroweak symmetry breaking. (author) 16. The hidden X-ray breaks in afterglow light curves International Nuclear Information System (INIS) Curran, P. A.; Wijers, R. A. M. J.; Horst, A. J. van der; Starling, R. L. C. 2008-01-01 Gamma-Ray Burst (GRB) afterglow observations in the Swift era have a perceived lack of achromatic jet breaks compared to the BeppoSAX, or pre-Swift era. Specifically, relatively few breaks, consistent with jet breaks, are observed in the X-ray light curves of these bursts. If these breaks are truly missing, it has serious consequences for the interpretation of GRB jet collimation and energy requirements, and the use of GRBs as standard candles.Here we address the issue of X-ray breaks which are possibly 'hidden' and hence the light curves are misinterpreted as being single power-laws. We show how a number of precedents, including GRB 990510 and GRB 060206, exist for such hidden breaks and how, even with the well sampled light curves of the Swift era, these breaks may be left misidentified. We do so by synthesising X-ray light curves and finding general trends via Monte Carlo analysis. Furthermore, in light of these simulations, we discuss how to best identify achromatic breaks in afterglow light curves via multi-wavelength analysis 17. DNA double-strand breaks & poptosis in the testis NARCIS (Netherlands) Hamer, Geert 2003-01-01 During spermatogenesis, DNA damage is a naturally occurring event. At a certain stage, during the first meiotic prophase, DNA breaks are endogenously induced and even required for meiotic recombination. We studied these DNA breaks but also used ionizing radiation (IR) to induce DNA double-strand 18. DNA breaks early in replication in B cell cancers Science.gov (United States) Research by scientists at the NCI has identified a new class of DNA sites in cells that break early in the replication process. They found that these break sites correlate with damage often seen in B cell cancers, such as diffuse large B cell lymphoma. 19. Burrowing as a novel voluntary strength training method for mice: A comparison of various voluntary strength or resistance exercise methods. Science.gov (United States) Roemers, P; Mazzola, P N; De Deyn, P P; Bossers, W J; van Heuvelen, M J G; van der Zee, E A 2018-04-15 Voluntary strength training methods for rodents are necessary to investigate the effects of strength training on cognition and the brain. However, few voluntary methods are available. The current study tested functional and muscular effects of two novel voluntary strength training methods, burrowing (digging a substrate out of a tube) and unloaded tower climbing, in male C57Bl6 mice. To compare these two novel methods with existing exercise methods, resistance running and (non-resistance) running were included. Motor coordination, grip strength and muscle fatigue were measured at baseline, halfway through and near the end of a fourteen week exercise intervention. Endurance was measured by an incremental treadmill test after twelve weeks. Both burrowing and resistance running improved forelimb grip strength as compared to controls. Running and resistance running increased endurance in the treadmill test and improved motor skills as measured by the balance beam test. Post-mortem tissue analyses revealed that running and resistance running induced Soleus muscle hypertrophy and reduced epididymal fat mass. Tower climbing elicited no functional or muscular changes. As a voluntary strength exercise method, burrowing avoids the confounding effects of stress and positive reinforcers elicited in forced strength exercise methods. Compared to voluntary resistance running, burrowing likely reduces the contribution of aerobic exercise components. Burrowing qualifies as a suitable voluntary strength training method in mice. Furthermore, resistance running shares features of strength training and endurance (aerobic) exercise and should be considered a multi-modal aerobic-strength exercise method in mice. Copyright © 2017 Elsevier B.V. All rights reserved. 20. Smiles count but minutes matter: responses to classroom exercise breaks. Science.gov (United States) Howie, Erin K; Newman-Norlund, Roger D; Pate, Russell R 2014-09-01 To determine the subjective responses of teachers and students to classroom exercise breaks, and how responses varied by duration. This mixed-methods experimental study included focus groups with teachers (N = 8) and 4(th)- and 5(th)-grade students (N = 96). Students participated in 5-, 10-, and 20-minute exercise breaks and 10 minutes of sedentary activity. In an additional exploratory analysis, video-tapes of each condition were coded and compared for positive affect. Students and teachers discussed multiple benefits, but teachers discussed barriers to implementing regular breaks of 5-minutes or more. Students exhibited higher positive affect during each exercise condition. Classroom exercise breaks are an enjoyable way to increase physical activity, but additional support may be needed to encourage teachers to implement breaks of 5 minutes or longer. 1. A synopsis of experimental activities on small-break LOCA International Nuclear Information System (INIS) Hein, D. 1984-01-01 Through reactor safety studies like WASH 1400 or the ''Deutsche Risiko-Studie'' the attention has turned from large break loss of coolant accidents to small breaks because of the high contribution of this type of accidents to core meltdown. But only after the TMI-2 accident were also the main activities in the experimental fields shifted world-wide to the small break LOCAs. Since TMI numerous research programs have either been finished or are underway. This review paper presents: a classification of the various types of transients according to break size; a discussion of major physical phenomena associated with a small break LOCA, and a description of a few selected research programs and the most important results achieved. (author) 2. Breaking gold nano-junctions simulation and analysis DEFF Research Database (Denmark) Lauritzen, Kasper Primdal , to predict the structure of a gold junction just as it breaks. This method is based on artificial neural networks and can be used on experimental data, even when it is trained purely on simulated data. The method is extended to other types of experimental traces, where it is trained without the use......Simulating the movements of individual atoms allows us to look at and investigate the physical processes that happen in an experiment. In this thesis I use simulations to support and improve experimental studies of breaking gold nano-junctions. By using molecular dynamics to study gold nanowires, I...... can investigate their breaking forces under varying conditions, like stretching rate or temperature. This resolves a confusion in the literature, where the breaking forces of two different breaking structures happen to coincide. The correlations between the rupture and reformation of a gold junction... 3. ANALISA BREAK EVENT POINT (BEP TERHADAP LABA PERUSAHAAN Directory of Open Access Journals (Sweden) Muhammad Yusuf 2015-09-01 Full Text Available Break event point or the break-even point can be defined as a situation where the operating company does not make a profit and not a loss. The goal is to provide the knowledge to increase knowledge about the break event point (the point of principal and its relationship with the company profit and to know how the results of the. Analysis break event point is very important for the leadership of the company to determine the production rate how much the cost will be equal to the amount of sales or in other words to determine the break event point we will determine the relationship between sales, production, selling price, cost, loss or profit, making it easier for leaders to take discretion.DOI: 10.15408/ess.v4i1.1955 4. Effects of fishing rope strength on the severity of large whale entanglements. Science.gov (United States) Knowlton, Amy R; Robbins, Jooke; Landry, Scott; McKenna, Henry A; Kraus, Scott D; Werner, Timothy B 2016-04-01 Entanglement in fixed fishing gear affects whales worldwide. In the United States, deaths of North Atlantic right (Eubalaena glacialis) and humpback whales (Megaptera novaeangliae) have exceeded management limits for decades. We examined live and dead whales entangled in fishing gear along the U.S. East Coast and the Canadian Maritimes from 1994 to 2010. We recorded whale species, age, and injury severity and determined rope polymer type, breaking strength, and diameter of the fishing gear. For the 132 retrieved ropes from 70 cases, tested breaking strength range was 0.80-39.63 kN (kiloNewtons) and the mean was 11.64 kN (SD 8.29), which is 26% lower than strength at manufacture (range 2.89-53.38 kN, mean = 15.70 kN [9.89]). Median rope diameter was 9.5 mm. Right and humpback whales were found in ropes with significantly stronger breaking strengths at time of manufacture than minke whales (Balaenoptera acuturostrata) (19.30, 17.13, and 10.47 mean kN, respectively). Adult right whales were found in stronger ropes (mean 34.09 kN) than juvenile right whales (mean 15.33 kN) and than all humpback whale age classes (mean 17.37 kN). For right whales, severity of injuries increased since the mid 1980s, possibly due to changes in rope manufacturing in the mid 1990s that resulted in production of stronger ropes at the same diameter. Our results suggest that broad adoption of ropes with breaking strengths of ≤ 7.56 kN (≤ 1700 lbsf) could reduce the number of life-threatening entanglements for large whales by at least 72%, and yet could provide sufficient strength to withstand the routine forces involved in many fishing operations. A reduction of this magnitude would achieve nearly all the mitigation legally required for U.S. stocks of North Atlantic right and humpback whales. Ropes with reduced breaking strength should be developed and tested to determine the feasibility of their use in a variety of fisheries. © 2015 The Authors. Conservation Biology published by Wiley 5. Breaking a dark degeneracy with gravitational waves Energy Technology Data Exchange (ETDEWEB) Lombriser, Lucas; Taylor, Andy, E-mail: llo@roe.ac.uk, E-mail: ant@roe.ac.uk [Institute for Astronomy, University of Edinburgh, Royal Observatory, Blackford Hill, Edinburgh, EH9 3HJ (United Kingdom) 2016-03-01 We identify a scalar-tensor model embedded in the Horndeski action whose cosmological background and linear scalar fluctuations are degenerate with the concordance cosmology. The model admits a self-accelerated background expansion at late times that is stable against perturbations with a sound speed attributed to the new field that is equal to the speed of light. While degenerate in scalar fluctuations, self-acceleration of the model implies a present cosmological tensor mode propagation at ∼<95 % of the speed of light with a damping of the wave amplitude that is ∼>5 % less efficient than in general relativity. We show that these discrepancies are endemic to self-accelerated Horndeski theories with degenerate large-scale structure and are tested with measurements of gravitational waves emitted by events at cosmological distances. Hence, gravitational-wave cosmology breaks the dark degeneracy in observations of the large-scale structure between two fundamentally different explanations of cosmic acceleration—a cosmological constant and a scalar-tensor modification of gravity. The gravitational wave event GW150914 recently detected with the aLIGO instruments and its potential association with a weak short gamma-ray burst observed with the Fermi GBM experiment may have provided this crucial measurement. 6. Flavor universal dynamical electroweak symmetry breaking International Nuclear Information System (INIS) Burdman, G.; Evans, N. 1999-01-01 The top condensate seesaw mechanism of Dobrescu and Hill allows electroweak symmetry to be broken while deferring the problem of flavor to an electroweak singlet, massive sector. We provide an extended version of the singlet sector that naturally accommodates realistic masses for all the standard model fermions, which play an equal role in breaking electroweak symmetry. The models result in a relatively light composite Higgs sector with masses typically in the range of (400 - 700) GeV. In more complete models the dynamics will presumably be driven by a broken gauged family or flavor symmetry group. As an example of the higher scale dynamics a fully dynamical model of the quark sector with a GIM mechanism is presented, based on an earlier top condensation model of King using broken family gauge symmetry interactions (that model was itself based on a technicolor model of Georgi). The crucial extra ingredient is a reinterpretation of the condensates that form when several gauge groups become strong close to the same scale. A related technicolor model of Randall which naturally includes the leptons too may also be adapted to this scenario. We discuss the low energy constraints on the massive gauge bosons and scalars of these models as well as their phenomenology at the TeV scale. copyright 1999 The American Physical Society 7. LHC Report: a break from luminosity production CERN Multimedia Jan Uythoven for the LHC team 2016-01-01 The LHC has been in great shape over the last few months, delivering over 20 fb-1 of integrated luminosity before the ICHEP conference in Chicago at the beginning of August. This is not much below the 25 fb-1 target for the whole of 2016. With this success in mind, a break in luminosity production was taken for six days, starting on 26 July 2016, for a machine development period. This year, 20 days of the LHC schedule are devoted to machine development with the aim of carrying out detailed studies of the accelerator. The 20 days are divided over five different periods, called MD blocks. They can be seen as an investment in the future, so the machine can produce collisions more efficiently in the months and years to come. A detailed programme is worked out for each MD block, whereby different specialist teams are assigned periods of four to twelve hours, depending on the topic, to perform their previously approved tests. The MD program continues 24 hours per day, as in normal physics operation. One... 8. Radiative Symmetry Breaking in Brane Models CERN Document Server Antoniadis, Ignatios; Quirós, Mariano 2000-01-01 We propose a way to generate the electroweak symmetry breaking radiatively in non-supersymmetric type I models with string scale in the TeV region. By identifying the Higgs field with a tree-level massless open string state, we find that a negative squared mass term can be generated at one loop. It is finite, computable and typically a loop factor smaller than the string scale, that acts as an ultraviolet cutoff in the effective field theory. When the Higgs open string has both ends confined on our world brane, its mass is predicted to be around 120 GeV, i.e. that of the lightest Higgs in the minimal supersymmetric model for large$\\tan\\beta$and$m_A$. Moreover, the string scale turns out to be one to two orders of magnitude higher than the weak scale. We also discuss possible effects of higher order string threshold corrections that might increase the string scale and the Higgs mass. 9. Breaking open the set top box Science.gov (United States) Banks, David; Wiley, Anthony; Catania, Nicolas; Coles, Alastair N.; Smith, Duncan; Baynham, Simon; Deliot, Eric; Chidzey, Rod 1998-02-01 In this paper we describe the work being done at HP Labs Bristol in the area of home networks and gateways. This work is based on the idea of breaking open the set top box by physically separating the access network specific functions from the application specific functions. The access network specific functions reside in an access network gateway that can be shared by many end user devices. The first section of the paper present the philosophy behind this approach. The end user devices and the access network gateways must be interconnected by a high bandwidth network which can offer a bounded delay service for delay sensitive traffic. We are advocating the use of IEEE 1394 for this network, and the next section of the paper gives a brief introduction to this technology. We then describe a prototype digital video broadcasting satellite compliant gateway that we have built. This gateway could be used, for example, by a PC for receiving a data service or by a digital TV for receiving an MPEG-2 video service. A control architecture is the presented which uses a PC application to provide a web based user interface to the system. Finally, we provide details of our work on extending the reach of IEEE 1394 and its standardization status. 10. Generalized geometry and partial supersymmetry breaking Energy Technology Data Exchange (ETDEWEB) Triendl, Hagen Mathias 2010-08-15 This thesis consists of two parts. In the first part we use the formalism of (exceptional) generalized geometry to derive the scalar field space of SU(2) x SU(2)-structure compactifications. We show that in contrast to SU(3) x SU(3) structures, there is no dynamical SU(2) x SU(2) structure interpolating between an SU(2) structure and an identity structure. Furthermore, we derive the scalar manifold of the low-energy effective action for consistent Kaluza-Klein truncations as expected from N = 4 supergravity. In the second part we then determine the general conditions for the existence of stable Minkowski and AdS N = 1 vacua in spontaneously broken gauged N = 2 supergravities and construct the general solution under the assumption that two appropriate commuting isometries exist in the hypermultiplet sector. Furthermore, we derive the low-energy effective action below the scale of partial supersymmetry breaking and show that it satisfies the constraints of N = 1 supergravity. We then apply the discussion to special quaternionic-Kaehler geometries which appear in the low-energy limit of SU(3) x SU(3)-structure compactifications and construct Killing vectors with the right properties. Finally we discuss the string theory realizations for these solutions. (orig.) 11. Protein Determinants of Meiotic DNA Break Hotspots Science.gov (United States) Fowler, Kyle R.; Gutiérrez-Velasco, Susana 2013-01-01 SUMMARY Meiotic recombination, crucial for proper chromosome segregation and genome evolution, is initiated by programmed DNA double-strand breaks (DSBs) in yeasts and likely all sexually reproducing species. In fission yeast, DSBs occur up to hundreds of times more frequently at special sites, called hotspots, than in other regions of the genome. What distinguishes hotspots from cold regions is an unsolved problem, although transcription factors determine some hotspots. We report the discovery that three coiled-coil proteins – Rec25, Rec27, and Mug20 – bind essentially all hotspots with unprecedented specificity even without DSB formation. These small proteins are components of linear elements, are related to synaptonemal complex proteins, and are essential for nearly all DSBs at most hotspots. Our results indicate these hotspot determinants activate or stabilize the DSB-forming protein Rec12 (Spo11 homolog) rather than promote its binding to hotspots. We propose a new paradigm for hotspot determination and crossover control by linear element proteins. PMID:23395004 12. Isospin symmetry breaking in sd shell nuclei International Nuclear Information System (INIS) Lam, Y.W. 2011-12-01 In the thesis, we develop a microscopic approach to describe the isospin-symmetry breaking effects in sd-shell nuclei. The work is performed within the nuclear shell model. A realistic isospin-conserving Hamiltonian is perfected by a charge-dependent part consisting of the Coulomb interaction and Yukawa-type meson exchange potentials to model charge-dependent forces of nuclear origin. The extended database of the experimental isobaric mass multiplet equation coefficients was compiled during the thesis work and has been used in a fit of the Hamiltonian parameters. The constructed Hamiltonian provides an accurate theoretical description of the isospin mixing nuclear states. A specific behaviour of the IMME (Isobaric Multiplet Mass Equation) coefficients have been revealed. We present two important applications: (i) calculations of isospin-forbidden proton emission amplitudes, which is often of interest for nuclear astrophysics, and (ii) calculation on corrections to nuclear Fermi beta decay, which is crucial for the tests of fundamental symmetries of the weak interaction. (author) 13. Rice Research to Break Yield Barriers Science.gov (United States) Verma, Vivek; Ramamoorthy, Rengasamy; Kohli, Ajay; Kumar, Prakash P. 2015-10-01 The world’s population continues to expand and it is expected to cross 9 billion by 2050. This would significantly amplify the demand for food, which will pose serious threats to global food security. Additional challenges are being imposed due to a gradual decrease in the total arable land and global environmental changes. Hence, it is of utmost importance to review and revise the existing food production strategies by incorporating novel biotechnological approaches that can help to break the crop yield barriers in the near future. In this review, we highlight some of the concerns hampering crop yield enhancements. The review also focuses on modern breeding techniques based on genomics as well as proven biotechnological approaches that enable identification and utilization of candidate genes. Another aspect of discussion is the important area of research, namely hormonal regulation of plant development, which is likely to yield valuable regulatory genes for such crop improvement efforts in the future. These strategies can serve as potential tools for developing elite crop varieties for feeding the growing billions. 14. Breaking of electroweak symmetry: origin and effects International Nuclear Information System (INIS) Delaunay, C. 2008-10-01 The Higgs boson appears as the corner stone of high energy physics, it might be the cause of the excess of matter that led to the formation of the structures of the universe and it seems that it drives the breaking of the electroweak symmetry. Moreover, when the stability at low energies of the Higgs boson is assured by an extra space dimension, it appears that this extra dimension can explain most issues in the flavor physics that are not understood by the standard model. The first chapter presents the main tools of effective field theories, the role of experimental data in the construction of theories valid beyond the standard model is discussed. The second chapter focuses on the electroweak baryogenesis that allows the testing of new physics via the electroweak phase transition. We detail the calculation of a Higgs potential at finite temperature. We follow the dynamics of the phase transition including nucleation an supercooling. Finally we investigate the prospects of gravity wave detection to see the effects of a strong electroweak phase transition. The 2 last chapters are dedicated to the physics of extra-dimension. The properties of the dynamics of scalar, vector fields with a 1/2 spin plunged in a 5 d. Anti de Sitter geometry are reviewed. We present a model of lepton masses and mixings based on the A 4 non-Abelian discrete symmetry. It is shown that this model does not contradict the tests of electroweak precision. (A.C.) 15. Generalized geometry and partial supersymmetry breaking International Nuclear Information System (INIS) Triendl, Hagen Mathias 2010-08-01 This thesis consists of two parts. In the first part we use the formalism of (exceptional) generalized geometry to derive the scalar field space of SU(2) x SU(2)-structure compactifications. We show that in contrast to SU(3) x SU(3) structures, there is no dynamical SU(2) x SU(2) structure interpolating between an SU(2) structure and an identity structure. Furthermore, we derive the scalar manifold of the low-energy effective action for consistent Kaluza-Klein truncations as expected from N = 4 supergravity. In the second part we then determine the general conditions for the existence of stable Minkowski and AdS N = 1 vacua in spontaneously broken gauged N = 2 supergravities and construct the general solution under the assumption that two appropriate commuting isometries exist in the hypermultiplet sector. Furthermore, we derive the low-energy effective action below the scale of partial supersymmetry breaking and show that it satisfies the constraints of N = 1 supergravity. We then apply the discussion to special quaternionic-Kaehler geometries which appear in the low-energy limit of SU(3) x SU(3)-structure compactifications and construct Killing vectors with the right properties. Finally we discuss the string theory realizations for these solutions. (orig.) 16. Golden Probe of Electroweak Symmetry Breaking CERN Document Server Chen, Yi; Spiropulu, Maria; Stolarski, Daniel; Vega-Morales, Roberto 2016-12-09 The ratio of the Higgs couplings to$WW$and$ZZ$pairs,$\\lambda_{WZ}$, is a fundamental parameter in electroweak symmetry breaking as well as a measure of the (approximate) custodial symmetry possessed by the gauge boson mass matrix. We show that Higgs decays to four leptons are sensitive, via tree level/1-loop interference effects, to both the magnitude and, in particular, overall sign of$\\lambda_{WZ}$. Determining this sign requires interference effects, as it is nearly impossible to measure with rate information. Furthermore, simply determining the sign effectively establishes the custodial representation of the Higgs boson. We find that$h\\to4\\ell$($4\\ell \\equiv 2e2\\mu, 4e, 4\\mu$) decays have excellent prospects of directly establishing the overall sign at a high luminosity 13 TeV LHC. We also examine the ultimate LHC sensitivity in$h\\to4\\ell$to the magnitude of$\\lambda_{WZ}$. Our results are independent of other measurements of the Higgs boson couplings and, in particular, largely free of assumpti... 17. Induction and repair of DNA double-strand breaks in rat cerebellar cortex exposed to 60Co γ-rays Science.gov (United States) Bulanova, T. S.; Zadneprianetc, M. G.; Ježková, L.; Kruglyakova, E. A.; Smirnova, E. V.; Boreyko, A. V. 2018-01-01 The induction and repair of DNA double-strand breaks are studied using the immunohistochemical staining procedure of paraffin-embedded rat cerebellum tissues after exposure to γ-rays of 60Co. The dose dependence of radiation-induced colocalized γH2AX/53BP1 foci is studied and its linear character is established. It is shown that these foci are efficiently eliminated 24 h after irradiation. 18. Prediction of radiotherapy induced normal tissue adverse reactions: the role of double-strand break repair International Nuclear Information System (INIS) Rao, B.S. Satish; Mumbrekar, K.D.; Goutham, H.V.; Donald, J.F.; Vadhiraja, M.B.; Satyamoorthy, K. 2016-01-01 We aimed at evaluating the predictive potential of DSB repair kinetics (using γH2AX foci assay) in lymphocytes and analysed the genetic variants in the selected radioresponsive candidate genes like XRCC3, LIG4, NBN, CD44, RAD9A, LIG3, SH3GL1, BAXS, XRCC1, MAD2L2 on the individual susceptibility to radiotherapy (RT) induced acute skin reactions among the head and neck cancer (HNC), and breast cancer (BC) patients. All the 183 HNC and 132 BC patients were treated by a 3-dimensional conformal RT technique 19. A method for predicting the fatigue life of pre-corroded 2024-T3 aluminum from breaking load tests Science.gov (United States) Gruenberg, Karl Martin Characterization of material properties is necessary for design purposes and has been a topic of research for many years. Over the last several decades, much progress has been made in identifying metrics to describe fracture mechanics properties and developing procedures to measure the appropriate values. However, in the context of design, there has not been as much success in quantifying the susceptibility of a material to corrosion damage and its subsequent impact on material behavior in the framework of fracture mechanics. A natural next step in understanding the effects of corrosion damage was to develop a link between standard material test procedures and fatigue life in the presence of corrosion. Simply stated, the goal of this investigation was to formulate a cheaper and quicker method for assessing the consequences of corrosion on remaining fatigue life. For this study, breaking load specimens and fatigue specimens of a single nominal gage (0.063″) of aluminum alloy 2024-T3 were exposed to three levels of corrosion. The breaking load specimens were taken from three different material lots, and the fatigue tests were carried out at three stress levels. All failed specimens, both breaking load and fatigue specimens, were examined to characterize the damage state(s) and failure mechanism(s). Correlations between breaking load results and fatigue life results in the presence of corrosion damage were developed using a fracture mechanics foundation and the observed mechanisms of failure. Where breaking load tests showed a decrease in strength due to increased corrosion exposure, the corresponding set of fatigue tests showed a decrease in life. And where breaking load tests from different specimen orientations exhibited similar levels of strength, the corresponding set of fatigue specimens showed similar lives. The spread from shortest to longest fatigue lives among the different corrosion conditions decreased at the higher stress levels. Life predictions based 20. The effect of interruptions and breaks on insight and impasses: Do you need a break right now? NARCIS (Netherlands) Beeftink, F.; van Eerde, W.; Rutte, C.G. 2008-01-01 Some time away from a problem, or incubation time, is found to be beneficial to creative problem solving. But are interruptions as equally helpful as breaks? An experiment was conducted to gain more insight into the differences between imposed and self-initiated breaks, and their effects on 1. When does taking a break help in negotiations? The influence of breaks and social motivation on negotiation processes and outcomes NARCIS (Netherlands) Harinck, F.; de Dreu, C.K.W. 2011-01-01 Most negotiations are interrupted from time to time to reflect on the negotiation or to do other pressing tasks. This study investigated how these breaks and the thoughts during these breaks influence subsequent negotiation behavior. Prosocially motivated dyads, with a tendency to think 2. Comparison of the DVI line break LOCA with the equivalent cold leg break with the ATLAS facility International Nuclear Information System (INIS) Choi, K. Y.; Cho, S.; Kang, K. H.; Park, H. S.; Kim, Y. S.; Baek, W. P. 2010-01-01 The APR1400 (Advanced Power Reactor, 1400 MWe) adopts a DVI (Direct Vessel Injection) method for ECC (Emergency Core Cooling) water delivery rather than a conventional CLI (Cold Leg Injection) method as an advanced safety feature. The break scenario of one DVI nozzle is taken into account in the small break LOCA analysis. Transient behavior during the DVI line breaks needs to be investigated and compared with the equivalent break on the cold leg. An 8.5-inch double-ended break of one DVI nozzle was simulated with the ATLAS, and a counterpart test for the DVI break was performed at the cold leg with the equivalent break size for comparison. This comparison will contribute to enhancing a comprehensive understanding of the thermal hydraulic behavior during transients. A constructed integral effect database is also used to validate the existing conservative safety analysis methodology and to develop a best-estimate safety analysis methodology for small-break LOCAs. A post-test calculation was performed with a best-estimate safety analysis code, MARS 3.1, in order to examine its prediction capability and to identify any code deficiencies for thermal hydraulic phenomena occurring during the transient. (authors) 3. Defining Nitrogen Kinetics for Air Break in Prebreath Science.gov (United States) Conkin, Johnny 2010-01-01 Actual tissue nitrogen (N2) kinetics are complex; the uptake and elimination is often approximated with a single half-time compartment in statistical descriptions of denitrogenation [prebreathe(PB)] protocols. Air breaks during PB complicate N2 kinetics. A comparison of symmetrical versus asymmetrical N2 kinetics was performed using the time to onset of hypobaric decompression sickness (DCS) as a surrogate for actual venous N2 tension. METHODS: Published results of 12 tests involving 179 hypobaric exposures in altitude chambers after PB, with and without airbreaks, provide the complex protocols from which to model N2 kinetics. DCS survival time for combined control and airbreaks were described with an accelerated log logistic model where N2 uptake and elimination before, during, and after the airbreak was computed with a simple exponential function or a function that changed half-time depending on ambient N2 partial pressure. P1N2-P2 = (Delta)P defined decompression dose for each altitude exposure, where P2 was the test altitude and P1N2 was computed N2 pressure at the beginning of the altitude exposure. RESULTS: The log likelihood (LL) without decompression dose (null model) was -155.6, and improved (best-fit) to -97.2 when dose was defined with a 240 min half-time for both N2 elimination and uptake during the PB. The description of DCS survival time was less precise with asymmetrical N2 kinetics, for example, LL was -98.9 with 240 min half-time elimination and 120 min half-time uptake. CONCLUSION: The statistical regression described survival time mechanistically linked to symmetrical N2 kinetics during PBs that also included airbreaks. The results are data-specific, and additional data may change the conclusion. The regression is useful to compute additional PB time to compensate for an airbreak in PB within the narrow range of tested conditions. 4. On the non-existence of a sharp cooling break in gamma-ray burst afterglow spectra International Nuclear Information System (INIS) Uhm, Z. Lucas; Zhang, Bing 2014-01-01 Although the widely used analytical afterglow model of gamma-ray bursts (GRBs) predicts a sharp cooling break ν c in its afterglow spectrum, the GRB observations so far rarely show clear evidence for a cooling break in their spectra or a corresponding temporal break in their light curves. Employing a Lagrangian description of the blast wave, we conduct a sophisticated calculation of the afterglow emission. We precisely follow the cooling history of non-thermal electrons accelerated into each Lagrangian shell. We show that a detailed calculation of afterglow spectra does not in fact give rise to a sharp cooling break at ν c . Instead, it displays a very mild and smooth transition, which occurs gradually over a few orders of magnitude in energy or frequency. The main source of this slow transition is that different mini shells have different evolutionary histories of the comoving magnetic field strength B, so that deriving the current value of ν c of each mini shell requires an integration of its cooling rate over the time elapsed since its creation. We present the time evolution of optical and X-ray spectral indices to demonstrate the slow transition of spectral regimes and discuss the implications of our result in interpreting GRB afterglow data. 5. Infliximab's influence on anastomotic strength and degree of inflammation in intestinal surgery in a rabbit model DEFF Research Database (Denmark) Frostberg, Erik; Ström, Petter; Gerke, Oke 2014-01-01 and conclusions. The purpose of this study was to investigate whether a single dose infliximab has an adverse effect on the anastomotic healing process, observed as reduced anastomotic breaking strength and histopathologically verified lower grade of inflammatory response, in the small intestine of a rabbit......BACKGROUND: Infliximab, a TNF-alpha inhibitor, is a potent anti-inflammatory drug in the treatment of inflammatory bowel diseases. Recent studies have investigated the effect of infliximab treatment on postoperative complications such as anastomotic leakage, however, with conflicting results...... of infliximab, given one week prior to surgery, does not have an impact on the anastomotic breaking strength on the third postoperative day in the small intestine of rabbits.... 6. Temperature dependence of deformation vs. strength properties of radiation-crosslinked polyethylene International Nuclear Information System (INIS) Matusevich, Yu.I.; Krul', L.P. 1992-01-01 The authors have studied the deformation vs. strength properties of radiation-crosslinked low-density polyethylene irradiated by γ irradiation up to doses from 5.0 sm-bullet 10 4 to 1.0 sm-bullet 10 6 Gy. The authors present the elongation diagrams taken at temperatures below and above the melting point of the polymer. The authors have obtained the dependences of the breaking stress and the pre-break elongation of the polymer on the irradiation doses and the testing temperature. Based on the kinetic lifetime equation, The authors calculated the values of the activation energy for mechanical fracture and the structure-sensitive coefficient γ. The authors show that in the crystalline state the strength of radiation-crosslinked polyethylene is determined by the chemical interactions along the chain of polymer macromolecules; and in molten polyethylene, by the crosslinks between the macromolecules. 8 refs., 4 figs., 1 tab 7. Electric strength of metal-ceramic brazed units of thermionic energy converters in cesium vapours International Nuclear Information System (INIS) Belousenko, A.P.; Vasilchenko, A.V.; Nikolaev, Y.V. 1989-01-01 The investigation of electric strength characteristics of the hollow metal-ceramic brazed units of thermionic energy converters with the insulator 1 = 10-50 mm from polycrystal aluminum oxide at the temperature T = 450-750 degrees and the cesium vapour pressure P Cs = 10 - 1 -10 3 Pa has been carried out. The experimental dependencies of the break-down voltage of the brazed units on the temperature, parameter P Cs · 1 and the value of surface electric resistance of the insulators are given as well as the empiric equations obtained with the help of experimental data for calculating the break-down voltage. A mechanism of ceramic insulator influence on electric strength characteristics of the cesium gap is investigated. A breakdown model explaining this influence is proposed 8. Rock strength under explosive loading International Nuclear Information System (INIS) Rimer, N.; Proffer, W. 1993-01-01 This presentation emphasizes the importance of a detailed description of the nonlinear deviatoric (strength) response of the surrounding rock in the numerical simulation of underground nuclear explosion phenomenology to the late times needed for test ban monitoring applications. We will show how numerical simulations which match ground motion measurements in volcanic tuffs and in granite use the strength values obtained from laboratory measurements on small core samples of these rocks but also require much lower strength values after the ground motion has interacted with the rock. The underlying physical mechanisms for the implied strength reduction are not yet well understood, and in fact may depend on the particular rock type. However, constitutive models for shock damage and/or effective stress have been used successfully at S-Cubed in both the Geophysics Program (primarily for DARPA) and the Containment Support Program (for DNA) to simulate late time ground motions measured at NTS in many different rock types 9. Strength Training and Your Child Science.gov (United States) ... in organized sports or activities such as baseball, soccer, or gymnastics usually can safely to start strength ... as biking and running, adequate hydration, and healthy nutrition. Reviewed by: Mary L. Gavin, MD Date reviewed: ... 10. DNA strand breaks, acute phase response and inflammation following pulmonary exposure by instillation to the diesel exhaust particle NIST1650b in mice DEFF Research Database (Denmark) Kyjovska, Zdenka O.; Jacobsen, Nicklas R.; Saber, Anne T. 2015-01-01 by the alkaline comet assay as DNA strand breaks in BAL cells, lung and liver tissue. The pulmonary acute phase response was analysed by Saa3 mRNA levels by real-time quantitative polymerase chain reaction. Instillation of DEP induced a strong neutrophil influx 1 and 3 days, but not 28 days post-exposure. Saa3 m... 11. Leak before break piping evaluation diagram International Nuclear Information System (INIS) Fabi, R.J.; Peck, D.A. 1994-01-01 Traditionally Leak Before Break (LBB) has been applied to the evaluation of piping in existing nuclear plants. This paper presents a simple method for evaluating piping systems for LBB during the design process. This method produces a piping evaluation diagram (PED) which defines the LBB requirements to the piping designer for use during the design process. Several sets of LBB analyses are performed for each different pipe size and material considered in the LBB application. The results of this method are independent of the actual pipe routing. Two complete LBB evaluations are performed to determine the maximum allowable stability load, one evaluation for a low normal operating load, and the other evaluation for a high normal operating load. These normal operating loads span the typical loads for the particular system being evaluated. In developing the allowable loads, the appropriate LBB margins are included in the PED preparation. The resulting LBB solutions are plotted as a set of allowable curves for the maximum design basis load, such is the seismic load versus the normal operating load. Since the required margins are already accounted for in the LBB PED, the piping designer can use the diagram directly with the results of the piping analysis and determine immediately if the current piping arrangement passes LBB. Since the LBB PED is independent of pipe routing, changes to the piping system can be evaluated using the existing PED. For a particular application, all that remains is to confirm that the actual materials and pipe sizes assumed in creating the particular design are built into the plant 12. PCB-Based Break-Out Box Science.gov (United States) Lee, Jason H. 2011-01-01 Break-out boxes (BOBs) are necessary for all electrical integration/cable checkouts and troubleshooting. Because the price of a BOB is high, and no work can be done without one, often the procedure stops, simply waiting for a BOB. A less expensive BOB would take less time in the integration, testing, and troubleshooting process. The PCB-based BOB works and looks the same as a standard JPL BOB, called Gold Boxes. The only differences between the old BOB and the new PCB-based BOB is that the new one has 80 percent of its circuitry in a printed circuit board. This process reduces the time for fabrication, thus making the BOBs less expensive. Moreover, because of its unique design, the new BOBs can be easily assembled and fixed. About 80 percent of the new PCB-based BOB is in a$22 (at the time of this reporting) custom-designed, yet commercially available PCB. This device has been used successfully to verify that BOB cables were properly made. Also, upon completion, the BOB was beeped out via a multimeter to ensure that all sockets on the connectors were properly connected to the respective banana jack. When compared to the Gold Box BOBs, the new BOB has many advantages. It is much more cost efficient, it delivers equal usability at substantially lower cost of the BOB, and the Gold Box is much heavier when compared to the new BOB. The new BOB is also a bit longer and much more versatile in that connectors are easily changeable and if a banana jack is broken, it can be replaced instead of throwing away an entire BOB.
13. Characteristics of structural loess strength and preliminary framework for joint strength formula
OpenAIRE
Rong-jian Li; Jun-ding Liu; Rui Yan; Wen Zheng; Sheng-jun Shao
2014-01-01
The strength of structural loess consists of the shear strength and tensile strength. In this study, the stress path, the failure envelope of principal stress (Kf line), and the strength failure envelope of structurally intact loess and remolded loess were analyzed through three kinds of tests: the tensile strength test, the uniaxial compressive strength test, and the conventional triaxial shear strength test. Then, in order to describe the tensile strength and shear strength of structural lo...
14. Attributing Changing Rates of Temperature Record Breaking to Anthropogenic Influences
Science.gov (United States)
King, Andrew D.
2017-11-01
Record-breaking temperatures attract attention from the media, so understanding how and why the rate of record breaking is changing may be useful in communicating the effects of climate change. A simple methodology designed for estimating the anthropogenic influence on rates of record breaking in a given time series is proposed here. The frequency of hot and cold record-breaking temperature occurrences is shown to be changing due to the anthropogenic influence on the climate. Using ensembles of model simulations with and without human-induced forcings, it is demonstrated that the effect of climate change on global record-breaking temperatures can be detected as far back as the 1930s. On local scales, a climate change signal is detected more recently at most locations. The anthropogenic influence on the increased occurrence of hot record-breaking temperatures is clearer than it is for the decreased occurrence of cold records. The approach proposed here could be applied in rapid attribution studies of record extremes to quantify the influence of climate change on the rate of record breaking in addition to the climate anomaly being studied. This application is demonstrated for the global temperature record of 2016 and the Central England temperature record in 2014.
15. Gauge unification, non-local breaking, open strings
International Nuclear Information System (INIS)
Trapletti, M.
2005-01-01
The issue of non-local GUT symmetry breaking is addressed in the context of open string model building. We study Z N xZ M ' orbifolds with all the GUT-breaking orbifold elements acting freely, as rotations accompanied by translations in the internal space. We consider open strings quantized on these backgrounds, distinguishing whether the translational action is parallel or perpendicular to the D-branes. GUT breaking is impossible in the purely perpendicular case, non-local GUT breaking is instead allowed in the purely parallel case. In the latter, the scale of breaking is set by the compactification moduli, and there are no fixed points with reduced gauge symmetry, where dangerous explicit GUT-breaking terms could be located. We investigate the mixed parallel+perpendicular case in a Z 2 xZ 2 ' example, having also a simplified field theory realization. It is a new S 1 /Z 2 xZ 2 ' orbifold-GUT model, with bulk gauge symmetry SU(5)xSU(5) broken locally to the Standard Model gauge group. In spite of the locality of the GUT symmetry breaking, there is no localized contribution to the running of the coupling constants, and the unification scale is completely set by the length of S 1
16. Strength and fracture behavior of aluminide matrix composites with ceramic fibers
Energy Technology Data Exchange (ETDEWEB)
Inoue, M.; Suganuma, K.; Niihara, K.
1999-07-01
This paper investigates the fracture behavior of FeAl and Ni{sub 3}Al matrix composites with ceramic continuous fibers 8.5--10 {micro}m in diameter. When stress is applied to these composites, multiple-fracture of fibers predominantly occurs before matrix cracking, because the load carried by the fibers reaches their fracture strength. Fragments which remain longer than the critical length can provide significant strengthening through load bearing even though fiber breaking has occurred. The ultimate fracture strength of the composites also depends on stress relaxation by plastic deformation of the matrix at a crack tip in the multiple-fractured fibers. Ductilizing of the matrix by B doping improves the ultimate strength at ambient temperatures in both composites. However, their mechanical properties at elevated temperatures are quite different. In the case of Ni{sub 3}Al matrix composites, embrittlement of the matrix is undesirable for high strength and reliability at 873--973 K.
17. The Impact of Biomechanics in Tissue Engineering and Regenerative Medicine
Science.gov (United States)
Butler, David L.; Goldstein, Steven A.; Guo, X. Edward; Kamm, Roger; Laurencin, Cato T.; McIntire, Larry V.; Mow, Van C.; Nerem, Robert M.; Sah, Robert L.; Soslowsky, Louis J.; Spilker, Robert L.; Tranquillo, Robert T.
2009-01-01
Biomechanical factors profoundly influence the processes of tissue growth, development, maintenance, degeneration, and repair. Regenerative strategies to restore damaged or diseased tissues in vivo and create living tissue replacements in vitro have recently begun to harness advances in understanding of how cells and tissues sense and adapt to their mechanical environment. It is clear that biomechanical considerations will be fundamental to the successful development of clinical therapies based on principles of tissue engineering and regenerative medicine for a broad range of musculoskeletal, cardiovascular, craniofacial, skin, urinary, and neural tissues. Biomechanical stimuli may in fact hold the key to producing regenerated tissues with high strength and endurance. However, many challenges remain, particularly for tissues that function within complex and demanding mechanical environments in vivo. This paper reviews the present role and potential impact of experimental and computational biomechanics in engineering functional tissues using several illustrative examples of past successes and future grand challenges. PMID:19583462
18. From DNA lesions to tissue malfunction
International Nuclear Information System (INIS)
Denekamp, J.
1989-01-01
After large doses of radiation, tissues fail to function when the proliferating cells lose their clonogenic ability. This results from unrepaired or misrepaired double strand breaks in the DNA. The lesions are inflicted immediately but there is a variable latent period before tissue damage is expressed. This ranges from a few days in intestine, to weeks in skin, and to months or years in deep visceral tissues, e.g. heart, lung, kidney, spinal cord. The latency relates to the proliferation kinetics of each tissue component. Doses of 10-30 Gy do not cause serious functional defects in differentiated cells, but they prevent successful mitosis in proliferating cells. Thus each tissue continues to function until its differentiated cells are lost by normal wear and tear processes. After a time which relates to the natural lifespan of the differentiated cells, failure to provide replacement cells from the proliferating compartment becomes important and the tissue shows atrophy and eventually a functional deficit. If the radiation exposure is divided into a series of smaller exposures or is given at a low dose-rate, the biochemical repair of DNA is more effective and less damage is observed. After high LET ionizing radiation, e.g. neutrons or α particles, the response is almost linear and is not affected by doserate or fractionation. (author)
19. Composite quarks and leptons from dynamical supersymmetry breaking without messengers
International Nuclear Information System (INIS)
Arkani-Hamed, N.; Luty, M.A.; Terning, J.
1998-01-01
We present new theories of dynamical supersymmetry breaking in which the strong interactions that break supersymmetry also give rise to composite quarks and leptons with naturally small Yukawa couplings. In these models, supersymmetry breaking is communicated directly to the composite fields without open-quotes messengerclose quotes interactions. The compositeness scale can be anywhere between 10thinspTeV and the Planck scale. These models can naturally solve the supersymmetric flavor problem, and generically predict sfermion mass unification independent from gauge unification. copyright 1998 The American Physical Society
20. Amino acid chirality breaking by N-phosphorylation
International Nuclear Information System (INIS)
Zhao Yufen; Yan Qingjin.
1995-01-01
The chirality breaking of amino acid is a focus issue in the origin of life. For chemists, there are some interesting chemical approaches to solve the symmetry breaking problem. Our previous experiments indicated that when amino acids were phosphorylated, there were many bio-mimic reactions happened. In this paper, it was found that there had significant difference between the N-phosphoryl L- and D- amino acids such as serine and threonine. The optical rotation tracing experiments of the racemic N-phosphoamino acids also showed the similar results. The chirality breaking of amino acids by N-phosphorylation was a novel phenomena. (author). 3 refs, 1 fig. Abstract only
1. RG analysis of magnetic catalysis in dynamical symmetry breaking
International Nuclear Information System (INIS)
Hong, Deog Ki; Kim, Youngman
1996-01-01
We perform the renormalization group analysis on the dynamical symmetry breaking under strong external magnetic field, studied recently by Gusynin, Miransky and Shovkovy. We find that any attractive four-Fermi interaction becomes strong in the low energy, thus leading to dynamical symmetry breaking. When the four-Fermi interaction is absent, the β-function for the electromagnetic coupling vanishes in the leading order in 1/N. By solving the Schwinger-Dyson equation for the fermion propagator, we show that in 1/N expansion, for any electromagnetic coupling, dynamical symmetry breaking occurs due to the presence of Landau energy gap by the external magnetic field. 5 refs
2. NPP Krsko Containment Response Following Main Steam Line Break
International Nuclear Information System (INIS)
Spalj, S.; Grgic, D.; Cavlina, N.
2000-01-01
This paper presents the calculation of thermohydraulic environmental parameters (pressure and temperature) inside containment of Krsko NPP after postulated Main Steam Line Break (MSLB) accident. This analysis was done as a part of the ambient parameters specification in the frame of the NPP Krsko Equipment Qualification (EQ) project. The RELAP5/mod2 computer code was used for the determination of MSLB mass and energy release and computer code GOTHIC was used to calculate pressure and temperature profiles inside NPP Krsko containment. The analysis was performed for spectrum of break sizes to account for possible steam superheating during accidents with smaller break sizes. (author)
3. Charge and color breaking minima in supersymmetric models
International Nuclear Information System (INIS)
Brhlik, Michal
2001-01-01
Supersymmetric extensions of the Standard Model include complicated scalar sectors leading to the possible occurrence of non-standard minima along suitable directions in the field space. These minima usually break charge and/or color and their presence in the theory would require an explanation why the universe has settled in the standard electroweak symmetry breaking minimum. In this talk I illustrate the relevance of the charge and color breaking minima in the framework of the minimal supergravity model and a string motivated Horava-Witten scenario
4. Direct gauge mediation of uplifted metastable supersymmetry breaking in supergravity
International Nuclear Information System (INIS)
Maru, Nobuhito
2010-01-01
We propose a direct gauge mediation model based on an uplifted metastable supersymmetry (SUSY) breaking coupled to supergravity. A constant superpotential plays an essential role to fix the moduli as well as breaking SUSY and R symmetry and the cancellation of the cosmological constant. Gaugino masses are generated at leading order of SUSY breaking scale, and comparable to the sfermion masses as in the ordinary gauge mediation. The Landau pole problem for QCD coupling can be easily solved since more than half of messengers become superheavy, which are heavier than the grand unified theory (GUT) scale.
5. Unified models of the QCD axion and supersymmetry breaking
Directory of Open Access Journals (Sweden)
Keisuke Harigaya
2017-08-01
Full Text Available Similarities between the gauge meditation of supersymmetry breaking and the QCD axion model suggest that they originate from the same dynamics. We present a class of models where supersymmetry and the Peccei–Quinn symmetry are simultaneously broken. The messengers that mediate the effects of these symmetry breakings to the Standard Model are identical. Since the axion resides in the supersymmetry breaking sector, the saxion and the axino are heavy. We show constraints on the axion decay constant and the gravitino mass.
6. Flavour breaking effects in the pseudoscalar meson decay constants
Energy Technology Data Exchange (ETDEWEB)
Bornyakov, V.G. [Institute for High Energy Physics, Protvino (Russian Federation); Institute of Theoretical and Experimental Physics, Moscow (Russian Federation); Far Eastern Federal Univ., Vladivostok (Russian Federation). School of Biomedicine; Horsley, R. [Edinburgh Univ. (United Kingdom). School of Physics and Astronomy; Nakamura, Y. [RIKEN Advanced Institute for Computational Science, Hyogo (Japan); Perlt, H.; Schiller, A. [Leipzig Univ. (Germany). Inst. fuer Theoretische Physik; Pleiter, D. [Forschungszentrum Juelich (Germany). Juelich Supercomputing Centre; Regensburg Univ. (Germany). Inst. fuer Theoretische Physik; Rakow, P.E.L. [Liverpool Univ. (United Kingdom). Theoretical Physics Division; Schierholz, G. [DESY Hamburg (Germany); Stueben, H. [Hamburg Univ. (Germany). Regionales Rechenzentrum; Zanotti, J.M. [Adelaide Univ. (Australia). CSSM, Dept. of Physics; Collaboration: QCDSF-UKQCD Collaborations
2016-12-14
The SU(3) flavour symmetry breaking expansion in up, down and strange quark masses is extended from hadron masses to meson decay constants. This allows a determination of the ratio of kaon to pion decay constants in QCD. Furthermore when using partially quenched valence quarks the expansion is such that SU(2) isospin breaking effects can also be determined. It is found that the lowest order SU(3) flavour symmetry breaking expansion (or Gell-Mann-Okubo expansion) works very well. Simulations are performed for 2+1 flavours of clover fermions at four lattice spacings.
7. Moduli/inflaton mixing with supersymmetry breaking field
Energy Technology Data Exchange (ETDEWEB)
Endo, M.; Takahashi, F. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)]|[Tokyo Univ. (Japan). Inst. for Cosmic Ray Research; Hamaguchi, K. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)]|[Tokyo Univ. (Japan). Dept. of Physics
2006-05-15
A heavy scalar field such as moduli or an inflaton generally mixes with a field responsible for the supersymmetry breaking. We study the scalar decay into the standard model particles and their superpartners, gravitinos, and the supersymmetry breaking sector, particularly paying attention to decay modes that proceed via the mixing between the scalar and the supersymmetry breaking field. The impacts of the new decay processes on cosmological scenarios are also discussed; the modulus field generically produces too much gravitinos, and most of the inflation models tend to result in too high reheating temperature and/or gravitino overproduction. (Orig.)
8. Spontaneous breaking of the BRST symmetry in the ABJM theory
International Nuclear Information System (INIS)
2014-01-01
In this paper, we will analyze the ghost condensation in the ABJM theory. We will perform our analysis in N=1 superspace. We show that in the Delbourgo–Jarvis–Baulieu–Thierry–Mieg gauge the spontaneous breaking of BRST symmetry can occur in the ABJM theory. This spontaneous breaking of BRST symmetry is caused by ghost–anti-ghost condensation. We will also show that in the ABJM theory, the ghost–anti-ghost condensates remain present in the modified abelian gauge. Thus, the spontaneous breaking of BRST symmetry in ABJM theory can even occur in the modified abelian gauge
9. Breaking cover: neural responses to slow and fast camouflage-breaking motion.
Science.gov (United States)
Yin, Jiapeng; Gong, Hongliang; An, Xu; Chen, Zheyuan; Lu, Yiliang; Andolina, Ian M; McLoughlin, Niall; Wang, Wei
2015-08-22
Primates need to detect and recognize camouflaged animals in natural environments. Camouflage-breaking movements are often the only visual cue available to accomplish this. Specifically, sudden movements are often detected before full recognition of the camouflaged animal is made, suggesting that initial processing of motion precedes the recognition of motion-defined contours or shapes. What are the neuronal mechanisms underlying this initial processing of camouflaged motion in the primate visual brain? We investigated this question using intrinsic-signal optical imaging of macaque V1, V2 and V4, along with computer simulations of the neural population responses. We found that camouflaged motion at low speed was processed as a direction signal by both direction- and orientation-selective neurons, whereas at high-speed camouflaged motion was encoded as a motion-streak signal primarily by orientation-selective neurons. No population responses were found to be invariant to the camouflage contours. These results suggest that the initial processing of camouflaged motion at low and high speeds is encoded as direction and motion-streak signals in primate early visual cortices. These processes are consistent with a spatio-temporal filter mechanism that provides for fast processing of motion signals, prior to full recognition of camouflage-breaking animals. © 2015 The Authors.
10. Breaking of axial symmetry in excited nuclei as identified in experimental data
Directory of Open Access Journals (Sweden)
Junghans Arnd R.
2017-01-01
Full Text Available A phenomenological prediction for radiative neutron capture is presented and compared to recent compilations of Maxwellian averaged cross sections and average radiative widths. Photon strength functions and nuclear level densities near the neutron separation energy are extracted from data without the assumption of axial symmetry – at variance to common usage. A satisfactory description is reached with a small number of global parameters when theoretical predictions on triaxiality (from constrained HFB calculations with the Gogny D1S interaction are inserted into conventional calculations of radiative neutron capture. The photon strength is parametrized using the sum of three Lorentzians (TLO in accordance to the dipole sum rule. The positions and widths are accounted for by the droplet model with surface dissipation without locally adjusted parameters. Level densities are influenced strongly by the significant collective enhancement based on the breaking of axial symmetry. With the less stringent requirement of invariance against rotation by 180∘ a global set of parameters which allows to describe the photon strength function and the level densities in the nuclear mass range from mass number 50 < A < 250 is found.
11. Mixed Connective Tissue Disease
Science.gov (United States)
Mixed connective tissue disease Overview Mixed connective tissue disease has signs and symptoms of a combination of disorders — primarily lupus, scleroderma and polymyositis. For this reason, mixed connective tissue disease ...
12. Undifferentiated Connective Tissue Disease
Science.gov (United States)
... Home Conditions Undifferentiated Connective Tissue Disease (UCTD) Undifferentiated Connective Tissue Disease (UCTD) Make an Appointment Find a Doctor ... by Barbara Goldstein, MD (February 01, 2016) Undifferentiated connective tissue disease (UCTD) is a systemic autoimmune disease. This ...
13. Soft Tissue Sarcoma
Science.gov (United States)
... muscles, tendons, fat, and blood vessels. Soft tissue sarcoma is a cancer of these soft tissues. There ... have certain genetic diseases. Doctors diagnose soft tissue sarcomas with a biopsy. Treatments include surgery to remove ...
14. A method for the calculation of collision strengths for complex atomic structures based on Slater parameter optimisation
International Nuclear Information System (INIS)
Fawcett, B.C.; Mason, H.E.
1989-02-01
This report presents details of a new method to enable the computation of collision strengths for complex ions which is adapted from long established optimisation techniques previously applied to the calculation of atomic structures and oscillator strengths. The procedure involves the adjustment of Slater parameters so that they determine improved energy levels and eigenvectors. They provide a basis for collision strength calculations in ions where ab initio computations break down or result in reducible errors. This application is demonstrated through modifications of the DISTORTED WAVE collision code and SUPERSTRUCTURE atomic-structure code which interface via a transformation code JAJOM which processes their output. (author)
15. Simulation of breaking waves using the high-order spectral method with laboratory experiments: wave-breaking energy dissipation
Science.gov (United States)
Seiffert, Betsy R.; Ducrozet, Guillaume
2018-01-01
We examine the implementation of a wave-breaking mechanism into a nonlinear potential flow solver. The success of the mechanism will be studied by implementing it into the numerical model HOS-NWT, which is a computationally efficient, open source code that solves for the free surface in a numerical wave tank using the high-order spectral (HOS) method. Once the breaking mechanism is validated, it can be implemented into other nonlinear potential flow models. To solve for wave-breaking, first a wave-breaking onset parameter is identified, and then a method for computing wave-breaking associated energy loss is determined. Wave-breaking onset is calculated using a breaking criteria introduced by Barthelemy et al. (J Fluid Mech https://arxiv.org/pdf/1508.06002.pdf, submitted) and validated with the experiments of Saket et al. (J Fluid Mech 811:642-658, 2017). Wave-breaking energy dissipation is calculated by adding a viscous diffusion term computed using an eddy viscosity parameter introduced by Tian et al. (Phys Fluids 20(6): 066,604, 2008, Phys Fluids 24(3), 2012), which is estimated based on the pre-breaking wave geometry. A set of two-dimensional experiments is conducted to validate the implemented wave breaking mechanism at a large scale. Breaking waves are generated by using traditional methods of evolution of focused waves and modulational instability, as well as irregular breaking waves with a range of primary frequencies, providing a wide range of breaking conditions to validate the solver. Furthermore, adjustments are made to the method of application and coefficient of the viscous diffusion term with negligible difference, supporting the robustness of the eddy viscosity parameter. The model is able to accurately predict surface elevation and corresponding frequency/amplitude spectrum, as well as energy dissipation when compared with the experimental measurements. This suggests the model is capable of calculating wave-breaking onset and energy dissipation
16. Reactive Strength Index: A Poor Indicator of Reactive Strength?
Science.gov (United States)
Healy, Robin; Kenny, Ian; Harrison, Drew
2017-11-28
The primary aim was to assess the relationships between reactive strength measures and associated kinematic and kinetic performance variables achieved during drop jumps. A secondary aim was to highlight issues with the use of reactive strength measures as performance indicators. Twenty eight national and international level sprinters, consisting of fourteen men and women, participated in this cross-sectional analysis. Athletes performed drop jumps from a 0.3 m box onto a force platform with dependent variables contact time (CT), landing time (TLand), push-off time (TPush), flight time (FT), jump height (JH), reactive strength index (RSI, calculated as JH / CT), reactive strength ratio (RSR, calculated as FT / CT) and vertical leg spring stiffness (Kvert) recorded. Pearson's correlation test found very high to near perfect relationships between RSI and RSR (r = 0.91 to 0.97), with mixed relationships found between RSI, RSR and the key performance variables, (Men: r = -0.86 to -0.71 between RSI/RSR and CT, r = 0.80 to 0.92 between RSI/RSR and JH; Women: r = -0.85 to -0.56 between RSR and CT, r = 0.71 between RSI and JH). This study demonstrates that the method of assessing reactive strength (RSI versus RSR) may be influenced by the performance strategies adopted i.e. whether an athlete achieves their best reactive strength scores via low CTs, high JHs or a combination. Coaches are advised to limit the variability in performance strategies by implementing upper and / or lower CT thresholds to accurately compare performances between individuals.
17. Lifting strength in two-person teamwork.
Science.gov (United States)
Lee, Tzu-Hsien
2016-01-01
This study examined the effects of lifting range, hand-to-toe distance, and lifting direction on single-person lifting strengths and two-person teamwork lifting strengths. Six healthy males and seven healthy females participated in this study. Two-person teamwork lifting strengths were examined in both strength-matched and strength-unmatched groups. Our results showed that lifting strength significantly decreased with increasing lifting range or hand-to-toe distance. However, lifting strengths were not affected by lifting direction. Teamwork lifting strength did not conform to the law of additivity for both strength-matched and strength-unmatched groups. In general, teamwork lifting strength was dictated by the weaker of the two members, implying that weaker members might be exposed to a higher potential danger in teamwork exertions. To avoid such overexertion in teamwork, members with significantly different strength ability should not be assigned to the same team.
18. High-energy behavior of field-strength interactions
International Nuclear Information System (INIS)
Levin, D.N.
1976-01-01
It is known that spontaneously broken gauge theories are the only renormalizable theories of massive spin-one particles with mass dimension less than or equal to 4. This paper describes a search for renormalizable interactions with higher mass dimension. Specifically, we examine the high-energy behavior of a class of models which involve field-strength interactions. Power counting shows that the high-energy behavior of these models is no worse than the naively estimated high-energy behavior of a gauge theory in the U gauge. Therefore, there may be a ''soft'' symmetry-breaking mechanism (for instance, a soft divergence of an antisymmetric tensor current) which enforces renormalizable high-energy behavior in the same way that spontaneously broken gauge invariance guarantees the renormalizability of gauge theories. This hope is supported by the existence of ''gauge theories'' of strings, which describe analogous interactions of strings and field strengths. Unfortunately, this idea is tarnished by explicit calculations in which renormalizability is imposed in the form of unitarity bounds. These unitarity bounds imply that all possible field-strength couplings must be zero and that the remaining interactions describe a spontaneously broken gauge theory. Thus this result supports an earlier conjecture that gauge theories are the only renormalizable theories of massive vector bosons
19. Density-dependent coupling constants and charge symmetry breaking
International Nuclear Information System (INIS)
Barreiro, L.A.
2001-01-01
The effect of the medium in the coupling constants implicate in a charge symmetry breaking on nuclear interactions. The amount of energy due to this modification can explain the Nolen-Schiffer anomaly. (author)
20. Approximate equations at breaking for nearshore wave transformation coefficients
Digital Repository Service at National Institute of Oceanography (India)
Chandramohan, P.; Nayak, B.U.; SanilKumar, V.
Based on small amplitude wave theory approximate equations are evaluated for determining the coefficients of shoaling, refraction, bottom friction, bottom percolation and viscous dissipation at breaking. The results obtainEd. by these equations...
1. New mechanisms of gauge-mediated supersymmetry breaking
International Nuclear Information System (INIS)
Randall, L.
1997-01-01
New mechanisms for the communication of supersymmetry breaking via gauge interactions are introduced. These models do not require complicated dynamics to induce a non-vanishing F term for a singlet. The first class of models communicates supersymmetry breaking to the visible sector through a ''mediator'' field that transforms under both a messenger gauge group of the dynamical supersymmetry breaking sector and the standard model gauge group. This model has a distinctive phenomenology; in particular, the scalar superpartners should be heavier than the gaugino superpartners by at least an order of magnitude. The second class of models has a phenomenology more similar to the ''standard'' messenger sectors. A singlet is incorporated, but the model does not require complicated mechanisms to generate a singlet F term. The role of the singlet is to couple fields from the dynamical symmetry breaking sector to fields transforming under the standard model gauge group. We also mention a potential solution to the μ problem. (orig.)
2. Dynamical symmetry breaking as an alternative for Higg's mechanics
International Nuclear Information System (INIS)
Shellard, R.C.
1979-01-01
The effective action of a theory where dynamical symmetry breaking occurs is expanded in terms of loops, producing a Ginzburg-Landau-like Lagrangian reproducing fenomenologically the Higg's potencial. (L.C.) [pt
3. The self-breaking mechanism of atomic scale Au nanocontacts
International Nuclear Information System (INIS)
Nakazumi, Tomoka; Kiguchi, Manabu; Wada, Yasuo
2012-01-01
We have investigated the self-breaking mechanism of atomic scale Au nanocontacts at room temperature in air. In the conductance traces, we frequently observed traces showing both a 1G 0 (2e 2 /h) and 3G 0 plateaux, or only a 2G 0 plateau in the conductance regime below 3G 0 . The statistical analysis showed a negative correlation between the appearance of 1G 0 and 2G 0 peaks, and a positive correlation between 1G 0 and 3G 0 peaks. This conductance behavior suggested that the symmetric triple atomic rows changed into a symmetric single row, while the asymmetric double rows broke without changing into a symmetric single row. The regular self-breaking process can be explained by the breaking of the thermodynamically stable Au nanocontacts which were formed during the self-breaking of the contacts. (paper)
4. Local models of Gauge Mediated Supersymmetry Breaking in String Theory
CERN Document Server
Garcia-Etxebarria, I; Uranga, Angel M; Garcia-Etxebarria, Inaki; Saad, Fouad; Uranga, Angel M.
2006-01-01
We describe local Calabi-Yau geometries with two isolated singularities at which systems of D3- and D7-branes are located, leading to chiral sectors corresponding to a semi-realistic visible sector and a hidden sector with dynamical supersymmetry breaking. We provide explicit models with a 3-family MSSM-like visible sector, and a hidden sector breaking supersymmetry at a meta-stable minimum. For singularities separated by a distance smaller than the string scale, this construction leads to a simple realization of gauge mediated supersymmetry breaking in string theory. The models are simple enough to allow the explicit computation of the massive messenger sector, using dimer techniques for branes at singularities. The local character of the configurations makes manifest the UV insensitivity of the supersymmetry breaking mediation.
5. [Breaking bad news in oncology: the Belgian experience].
Science.gov (United States)
Delevallez, F; Lienard, A; Gibon, A-S; Razavi, D
2014-10-01
Breaking bad news is a complex and frequent clinical task for physicians working in oncology. It can have a negative impact on patients and their relatives who are often present during breaking bad news consultations. Many factors influence how the delivery of bad news will be experienced especially the communication skills used by physicians. A three-phase process (post-delivery phase, delivery phase, pre-delivery phase) has been developed to help physician to handle this task more effectively. Communication skills and specific breaking bad news training programs are both necessary and effective. A recent study conducted in Belgium has shown their impact on the time allocated to each of the three phases of this process, on the communication skills used, on the inclusion of the relative in the consultation and on physicians' physiological arousal. These results underscore the importance of promoting intensive communication skills and breaking bad news training programs for health care professionals.
6. Isospin breaking in the pion-nucleon scattering lengths
International Nuclear Information System (INIS)
Hoferichter, Martin; Kubis, Bastian; Meissner, Ulf-G.
2009-01-01
We analyze isospin breaking through quark mass differences and virtual photons in the pion-nucleon scattering lengths in all physical channels in the framework of covariant baryon chiral perturbation theory.
7. Isospin breaking in the pion-nucleon scattering lengths
Energy Technology Data Exchange (ETDEWEB)
Hoferichter, Martin [Helmholtz-Institut fuer Strahlen- und Kernphysik (Theorie) and Bethe Center for Theoretical Physics, Universitaet Bonn, D-53115 Bonn (Germany); Kubis, Bastian [Helmholtz-Institut fuer Strahlen- und Kernphysik (Theorie) and Bethe Center for Theoretical Physics, Universitaet Bonn, D-53115 Bonn (Germany)], E-mail: kubis@itkp.uni-bonn.de; Meissner, Ulf-G. [Helmholtz-Institut fuer Strahlen- und Kernphysik (Theorie) and Bethe Center for Theoretical Physics, Universitaet Bonn, D-53115 Bonn (Germany); Institut fuer Kernphysik (Theorie), Institute for Advanced Simulation, and Juelich Center for Hadron Physics, Forschungszentrum Juelich, D-52425 Juelich (Germany)
2009-07-06
We analyze isospin breaking through quark mass differences and virtual photons in the pion-nucleon scattering lengths in all physical channels in the framework of covariant baryon chiral perturbation theory.
8. Breaking the Emotional Barrier through the Bibliotherapeutic Process.
Science.gov (United States)
Ouzts, Dan T.
1984-01-01
Reviews literature concerning bibliotherapy and concludes that it can be of value to a child's overall emotional development and may help in breaking emotional barriers to learning. Discusses the role of the reading teacher in the bibliotherapeutic process. (FL)
9. Mental health and Citizenship: Breaking down barriers in Brazil and ...
International Development Research Centre (IDRC) Digital Library (Canada)
2015-04-14
Apr 14, 2015 ... Mental health and Citizenship: Breaking down barriers in Brazil and Canada ... struggle to exercise full citizenship in health care systems that leave little room ... Digital solidarity, key to Africa's development — interview with Mr ...
10. The Coulomb break-up of 9Be
International Nuclear Information System (INIS)
Macdonald, E.W.; Shotter, A.C.; Branford, D.; Rahighi, J.; Davinson, T.; Davis, N.J.
1992-01-01
Kinematically complete data is presented on the break-up reaction 120 Sn( 9 Be, 8 Be g.s +n) 120 Sn g.s. at E beam =90 MeV for several scattering angles inside the grazing angle. These data are compared with the predictions of a Coulomb break-up model. It is shown that the data can be understood in terms of the Coulomb model provided some account is taken of the interactions of the break-up fragments with the target. Analysis of the 9 Be break-up data, using radio-isotope measurements of the 9 Be(γ, n) cross-section, indicates that for this photo-disintegration reaction there is probably a significant direct component to the threshold cross-section, in addition to a threshold resonance at 1.69 MeV. (orig.)
11. Dam-Break Flood Analysis Upper Hurricane Reservoir, Hartford, Vermont
National Research Council Canada - National Science Library
Acone, Scott
1995-01-01
.... Various dam break flood conditions were modeled and inundation maps developed. Based on this analysis the dam is rated a Class 2 or significant hazard category in terms of its potential to cause downstream damage...
12. Yukawa unification in moduli-dominant SUSY breaking
International Nuclear Information System (INIS)
Khalil, S.; Tatsuo Kobayashi
1997-07-01
We study Yukawa in string models with moduli-dominant SUSY breaking. This type of SUSY breaking in general leads to non-universal soft masses, i.e. soft scalar masses and gaugino masses. Such non-universality is important for phenomenological aspects of Yukawa unification, i.e., successful electroweak breaking, SUSY corrections to the bottom mass and the branching ratio of b → sγ. We show three regions in the whole parameter space which lead to successful electroweak breaking and allow small SUSY corrections to the bottom mass. For these three regions we investigated the b → sγ decay and mass spectra. (author). 26 refs, 6 figs
13. Digital decoupling and disentangling: towards design for romantic break up
NARCIS (Netherlands)
Herron, D.; Moncur, W.; van den Hoven, E.
2017-01-01
Romantic relationships are often facilitated through digital technologies, such as social networking sites and communication services. They are also facilitated through 'digital possessions', such as messages sent to mobile devices and photos shared through social media. When individuals break up,
14. Spontaneous charge breaking in the NMSSM: dangerous or not?
Energy Technology Data Exchange (ETDEWEB)
Krauss, Manuel E.; Opferkuch, Toby [Bethe Center for Theoretical Physics and Physikalisches Institut der Universitaet Bonn, Bonn (Germany); Staub, Florian [Karlsruhe Institute of Technology, Institute for Theoretical Physics (ITP), Karlsruhe (Germany); Karlsruhe Institute of Technology, Institute for Nuclear Physics (IKP), Eggenstein-Leopoldshafen (Germany)
2017-05-15
We investigate the impact of charge-breaking minima on the vacuum stability of the NMSSM. We concentrate on the case of vanishing A-terms in the sfermion sector, i.e. the only potentially dangerous sources of charge breaking are vacuum expectation values of the charged Higgs fields. We find that, in contrast to Two-Higgs-Doublet Models like the MSSM, at both tree and loop level there exist global charge-breaking minima. Consequently, many regions of parameter space are rendered metastable, which otherwise would have been considered stable if these charge-breaking minima were neglected. However, the inclusion of these new scalar field directions has little impact on otherwise metastable vacuum configurations. (orig.)
15. Nearshore bars and the break-point hypothesis
Science.gov (United States)
Sallenger, A.H.; Howd, P.A.
1989-01-01
The set of hypotheses calling for bar formation at the break point was tested with field data. During two different experiments, waves were measured across the surf zone coincident with the development of a nearshore bar. We use a criterion, based on the wave height to depth ratio, to determine the offshore limit of the inner surf zone. During the first experiment, the bar became better developed and migrated offshore while remaining well within the inner surf zone. During the second experiment, the surf zone was narrower and we cannot rule out the possibility of break point processes contributing to bar development. We conclude that bars are not necessarily coupled with the break point and can become better developed and migrate offshore while being in the inner surf zone landward from initial wave breaking in the outer surf zone. ?? 1989.
Science.gov (United States)
... older kids who continue to suck their thumbs, peer pressure at school usually ends the habit. Remember, though, ... an incredibly difficult habit to break. Remember, though, peer pressure typically leads kids to stop daytime sucking habits ...
17. Mind the Gap: Women in STEM Career Breaks
Directory of Open Access Journals (Sweden)
Catherine Mavriplis
2010-03-01
Full Text Available There are two issues related to women and pathways to STEM careers. Recruitment to the field is one aspect. The second issue is the retention of women in STEM fields. This paper reports on the structured interviews with 14 women who have taken career breaks sometime after receiving their PhD in order to understand the pressures in place to take such breaks, how women remain connected (or not to their field during the break and issues related to re-entering the field after a career break. Suggestions based on the interviews include enhancements for women’s preparation for STEM fields and changes to the STEM culture itself. We suggest the inclusion workshops to detail what they might expect in their career and a provision for networking opportunities. We urge changes in the fee structure for society membership, differences in how resumes are reviewed as well as changes in maternity and child care leave.
18. Time dependent micromechanics in continuous graphite fiber/epoxy composites with fiber breaks
Science.gov (United States)
Zhou, Chao Hui
Time dependent micromechanics in graphite fiber/epoxy composites around fiber breaks was investigated with micro Raman spectroscopy (MRS) and two shear-lag based composite models, a multi-fiber model (VBI) and a single fiber model (SFM), which aim at predicting the strain/stress evolutions in the composite from the matrix creep behavior and fiber strength statistics. This work is motivated by the need to understand the micromechanics and predict the creep-rupture of the composites. Creep of the unfilled epoxy was characterized under different stress levels and at temperatures up to 80°C, with two power law functions, which provided the modeling parameters used as input for the composite models. Both the VBI and the SFM models showed good agreement with the experimental data obtained with MRS, when inelasticity (interfacial debonding and/or matrix yielding) was not significant. The maximum shear stress near a fiber break relaxed at t-alpha/2 (or as (1+ talpha)-1/2) and the load recovery length increased at talpha/2(or (1+ talpha)1/2) following the model predictions. When the inelastic zone became non-negligible, the viscoelastic VBI model lost its competence, while the SFM with inelasticity showed good agreement with the MRS measurements. Instead of using the real fiber spacing, an effective fiber spacing was used in model predictions, taking into account of the radial decay of the interfacial shear stress from the fiber surface. The comparisons between MRS data and the SFM showed that inelastic zone would initiate when the shear strain at the fiber end exceeds a critical value gammac which was determined to be 5% for this composite system at room temperature and possibly a smaller value at elevated temperatures. The stress concentrations in neighboring intact fibers played important roles in the subsequent fiber failure and damage growth. The VBI model predicts a constant stress concentration factor, 1.33, for the 1st nearest intact fiber, which is in good
19. Mast cell degranulation breaks peripheral tolerance.
Science.gov (United States)
de Vries, V C; Wasiuk, A; Bennett, K A; Benson, M J; Elgueta, R; Waldschmidt, T J; Noelle, R J
2009-10-01
Mast cells (MC) have been shown to mediate regulatory T-cell (T(reg))-dependent, peripheral allograft tolerance in both skin and cardiac transplants. Furthermore, T(reg) have been implicated in mitigating IgE-mediated MC degranulation, establishing a dynamic, reciprocal relationship between MC and T(reg) in controlling inflammation. In an allograft tolerance model, it is now shown that intragraft or systemic MC degranulation results in the transient loss of T(reg) suppressor activities with the acute, T-cell dependent rejection of established, tolerant allografts. Upon degranulation, MC mediators can be found in the skin, T(reg) rapidly leave the graft, MC accumulate in the regional lymph node and the T(reg) are impaired in the expression of suppressor molecules. Such a dramatic reversal of T(reg) function and tissue distribution by MC degranulation underscores how allergy may causes the transient breakdown of peripheral tolerance and episodes of acute T-cell inflammation.
20. Mass generation and chiral symmetry breaking by pseudoparticles
International Nuclear Information System (INIS)
Hietarinta, J.; Palmer, W.F.; Pinsky, S.S.
1978-01-01
Massless QCD is studied with regard to mass generation and chiral SU(N/sub f/) symmetry breaking from pseudoparticle effects. While mass is generated when there is only one massless quark, and chiral U(1) is always broken, no rigorous indication of the breaking of chiral SU(N/sub f/) and mass generation is seen when there are more than one massless quarks in the original theory | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.6882284879684448, "perplexity": 4350.576250507115}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2018-30/segments/1531676591455.76/warc/CC-MAIN-20180720002543-20180720022543-00331.warc.gz"} |
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1JWtLISHED BY
SAt.US & SEASON.
PRICE,
For a yearlen dollars-fQor-six months, six dollars.,
Those subscribing for a year, wh6 do (ot, either at the time of
ordering the paper, or obsequnently, give notice of their wish#
to have the aperdiseoutinued at tlie expiration of their year,
will be presumed a7 desiring its' ontinuance until counter-
mande.I, ar;d it wiU.Je continued accordinglyat 'tie option ul
the Ediiors. '
BANK Of THi METROPOLIS, JAN. 1, 1836.
T HE Board bf I.ritlors have declared a dividend of
4 per cent. for the last half year.
jan 2--3taw2w GEO. THOMAS, Cashier.
DI. KING & JOHN. WILSON, Land and Gcne-
t* ral Aebits, Washington city, D. C. (,fice in the rooms
lately occupied by the Bank of the Mletropolis, corner of F oan-
55h streets. dec l-d6m
<. +WILtrAitM C. IPONELAN,
,"- Miniature Palnter,e .
S North side of Pennsylvania Avenue, one door west of 12th st.
jan 6-eolm
A CATALOGUE OF REASONS for using Dr.
Peters's celebrated Vegetable Pills.
1. Because they are exceedingly puoplar, which proves them
to be exceedingly good.
6. Because they are composed of simple which have the
power to do good in an immense number of cases, without pos-
sessing the means to do injury in any.
3. Because theyjare not a quack medicine, but the scientific
compound of'a regular physician, who has made his profession
the study of his life.
S4. BeCause they 'are not unpleasant to take, nbr distressing
to retain, while they aie most effective to operate.
5. Because they are recommended as a standard medicine
by the regular faculty.
'6. Because, by keeping the system in a natural state of ac-,
lion, they cure almost every disease which the human frame is
ifiidental to, .
7 ., Because they are cheap and portable, and will retainall
their virtues in full vigor, in any .climate, and for any 'i~eih of
me.'..
8. Because,.nowithstanding. fheir. simplicity and mildness,
they are onaofl he speediest purgative medicines which has
yet beev discovered. ..
9. Because they. are an tnfailing remedy for-procuring a
goodappetite:
10. Because in cases of spleen orf despondency, by their
healthy influence on the excited state of the body, they have a
most happy effect in calmimg and invigorating the mind.
SII. 1 because they effecttheir cures without the usual attend-
Sants ofdther pills, sickness and gripings.
12. Because, as well as being an unrivalled purifier of the
general system, they are a sovereign remedy for sick headache.
13. Because they differ 9bm the majority of medicines in
the fact that the more they are known the more they are ap-.
proved,
,14. Because, as their application produces no debility in the
System, they may be taken without producing iny- hindrance to
Sbusinesior the usual pursuits of every day life.
15, and lastly. -Because they are acknowledged to be an al-
most infallible remedy for bilious fever, fever and ague, dyspep-
sia, liver complaints, jaundice, asthma, dropsy, rheutmatism, en-
largement ortlie spleen, lowness bfspirits, piles, colic, heart-
\burn, nausea, distension of the stomach and bowels, flatlence,
habitual costiveneas, loss of apFetite, blotched or sallow com-
plexion, and in all eases of torpor of the bowels, where a mild
but effective medicine may-be requisite..
In short, the general voice. of the community has decided
that Dr. PETERS'S Vegetable Pills-are one ofthc happids1dis-
coveries of modern days, and altogether unrivalled as a general
soother of bodily afflictions. Prepared by Joseph Priestly Pe-
ters, M. D. No. 129 Liberty street, New York. Each box con-
tains 40 pills. Price 50 cents.
Be careful and inquire for Peters's Vegetable, Pills; they
are sold by all the principal druggists in Washington, Alexan-
dria, Georgetown, and Baltimore.
jan 8-eo6m
I LANK BOOKS.-The most extensive assortment of
Blank Books of every description, made of the best mate-
rias by a first-rate workman, is constantly for sale at Stationers'
Hall, at prices the most reasonable.
jan 12 W. FISCHER.
SEW CLOTHS, CASSIMERES, AND VEST-
INGS, which will be made up in the best manner, very
jan 6-eo2w (Globe)
HE DEMOCRATIC REVIEW, No. 2-Will be
: this morning issued, and can be procured at
F. TAYLOR'S Bookstore,
jan 3 Immediately east of Gadsby's Hotel.
HE YOUNG WIFE, or Duties of Woman in the
Marriage Relation; by' Wm. A. Alcott, author of the
Young Mother, Young Man s Guide, and House I Live in, and
editor of the Library of Health. For sale between 9th and 10th
streets, Pennsylvania avenue.' R. FARNHAM.
dec 11
W WALKING CANES AND WVHIPS.-A large
assortment of canes and whips, comprising almost every
description of both'articles, of the best quality and at the lowest
*prices. For sale at the old snuff, tobacco and fancy store, be-
tween 11th and 12th streets, Pennsylvania avenue.
jan 8 LEWIS JOHNSON.
W'ANTED, a situation as teacher, by a graduate of an
"tVV. European university, who has been engaged in that
profession in this country during the last eight years. Ample
recommendations for strict morality and sound ability to in-
structin the Greek, Latin, and English languages, and in all
the mathematical and other branches of education necessary
colleges and universities,will be exhibited from private families,
and trustees of academies in the neighboring States in which
the advertiser has taught, besides testimonials from the uni-
C, E, through the city'post office, will be immediately attend-
ed to. jan 2-5t3taw
A DDISON'l PENCIL CASES.-The most exten-
sive assortment of Addison's superior Gold and Silver
Pencil Cases is constantly kept for sale at Stationers' Hall, at
prices from 50 cents to 20 dollars each.
URTON'S COMIC SONGSTER-For sale be-
tween Ninth and Tenth streets, Pennsylvania Avenue.
'dec 30 R. FARNHAM.
IREWOOD FOR SALE.-From one to two thou-
Ssand cords of the best Firewood for sale, on reasonable
terms, about from one to two miles from Georgetown Ferry, on
the west side of the river. The wood either cut and corded, or
sian.ding, to suit purchasers. Apply to J. W. Minor, Esq. at
the Glebe House, in the vicinity, or to the subscriber, in this
city. JOHN P. VAN NESS.
jan 5-tf
W ANTED.-South Carolina, Alabama, and Mississippi
Bank Notes, and Bank Checks, or Certificates of De-
posite. Also, New Orleans Funds. Apply to
W. S. NICHOLLS,
Pennsylvania Avenue.
Treasury Notes bought and sold at current rates.
.dec 27-3wd:
OCKHART'S LIFE OF SCOTT,vols. 4 and 5,
Boston edition, with a Portrait of Scott. For sale between
9th and 10th streets, Pennsylvania Avenue.
jan 5 R. FARNHAM.
ORTOISE SHELL AND OTHER COMBS.-
The subscriber has this day received from the manufacto-
ry an invoice of newest fashion Shell and other Combs, con-
sisting of Twist, Tuck, Narrow Top, Side, Neck, &c.
Also, Backgammon Boards, complete
Graces, Battledores and other Games of exercise
Superior Bead Bags, Long Silk Purses
Fine Pen and Pocket Knives
Best Rodgers's Scissors, &c. &c. for sale at the. lowest
S prices.
TFWIS .TOHNT ONN
WASHINGTON CANAL STEAMBOAT COM-
W PAN Y.-This company has. declared a dividend on
the captial stock thereof, whikh will 'be paid (tp stockholders)
on application at the Patriotic Bank, on and after Tuesday next,
the 16th ir.slant. A. B. WALLER,
.jn 13--3t Chair'n Cotn: ofrMariagetnent.
W AN ED IMMEDIATELY.-Two or three.smart
.active boys ; one to wait in the house, and the other. to'
work' ~t doors. They must be well recnninrend.d. Those
f'ronm the country %ill he;prerferred. Apply 10 thbe
Jau 13-3t ST~ AARD. COLUMiBIAN COLLEGE.
JOHTI'PRIVA.UX, Cook to the late Pe-ident J.,:kson,
would most respectfully announce to the citiz.r.s .,f Wash-
igitbon .thit he has established himself pernianeritly lietwe.n-i
tlie Six'and Seven buildings, directly' opposite the W\'t larkel,
an fii-.readv at all 'times to wait upon those who need his ser-
vitce. as a skilful and professed cook, either at their dtl ellirin.
or hiq ovu Resta',nant.. :Prom his long experience, lie flatters
himself competent to give general ratisfaciion, and at the same
tiie his changes will hemoderie.. jan 13--c.3w
P IANOS.-Additioual supply of superior German
ilanos.-Ju-t received, three more of those splendid'
instrudiento, of the same quality as those I have he"i4p'ore sold.,
'The tone of bheFe pi.inos is powerful and sweet, thgir case, of
superior cu'mr'dmahognyn, wih pillars and stand.-A-of ithe new-
est pattern ; also, bn-hand, .two m..ire of the same quality. I
wijl sell tlrege as low as instruments of such superior quality
can be botgght iLlthe UniQed States., Old Pianos+ received'in
part pay.; RICHARD IDAViS,
j-n 13-3t Pairfax street Alexpndria.
HORSESt OlI iALE.-Jumst arrived froni the North
ten'first rate Horses, all well broken to single and double har-'
ness, among which re three pairs of very superior matches,
not to I) surpassed by any in the city.-
Gentl'imen wishing to purchase willplease to call at.the Na-
tio-al Hotel Livery Stables, where they can be seen.
jan 13--3
PETERS' VEG ETAIILl .-PI1 LS, having stood
the test of experience, are recommended to thl Public as
a cheap and superior family medicine. Wlientatke according
to the directions accompanying them, they are highly beneficial
in the prevention and cure of bilious fevers, fever and ague, dys-
pepsia, liver complaints, dbch headache, jaundice, asthilla, 4rop-
sy, rheumatism, enlargement of the spleen, piles, cholic, female
obstructions, heartiuhrn, pausea, furred tongue, distension of the
stomach and bowels, incipient diarrhea, flatulence, habitual
costiveness, loss of appetite, blotched or sallow complexion, and
in all cases of. t(dpor of the bowels, where a cathartic or an ape-
rient is needed.
They are t.xceedingly mild in their operation, producing nei-
ther nausea,griping, nor debility.
Prepared by Joseph lriestly Peters, M. D., at his- Institu-
tion for the cure pf obstinate diseases by means of vegetable
rceties, No. 129, Liberty street, New Ytirk.
E- ac!h box contains 4-t pills. Price GO cents.
For sale by'S. J.TODD, C. TOTT, T. WATKINS,'NM.
GUNTON, JOHN F. CALLAN, and F. H \ARD,'Wash-
ington ; and by-WM. STABLER, C. FARQUHAR, and, \M..
HARPER, Alexandria; and in Georgetown, by 0.. lM." IIN'l
THICUM. ap --eoly.
willbe opened again on the 15ih of January next, under
the superintendence of its present Principal, Mr. C. A. LEWIS.
The course,of instruction wiJf e extensive, embracing the.
Latin, Greek, and Freich la'igifiges, History, Mathetnaticis,'
-the theory and practice of Sur~eying, the e .inents of Chem-
iitry, and Natural Philosophy; together wlth those brinclies
which constitute a goid English education. In the discharged
of the laborious duties of his station, the principal will be aided
by his present assistant, Mr. BUCKNER, and also by Mr. VAw
DOREW, a graduate of Princeton Colf ge, and highly recom-
mended by the Faculty ofthat institution. The discipline of
the school, though strict, will be parental and affectionate, and
every exertion used to promote the moral abd intellectual cul-
ture of those committed to its care. The superior advantages
of this institution, as a suitable place for the instruction of youth,
are well known to the Public. The whole expense, including
board, tuition, washing, &c. with the exception of bed, bedding,
towels, and candles, will be $120; for bed and bedding, if fur- nished, the charge will be$6.
Letters addressed to the Principal, at the Rappahannock
RICHARD BUCKNER, Jr.
JOHN TAYLOR, Jr. Trustees.
WILLIAM P. TAYLOR,
dec 16-2awlmo
C ONCORD ACADEMY.-The exercises of this sem-
inary for the year 1838 will commence on the 1st of Feb-
ruary, and terminate on the 30th of November.
The price of board and tuition, including washing, bedding,
and fuel, will be $100 for a session of five months, payable in advance. The course of instruction embraces the languages and sciences generally, and is designed to prepare students thoroughly for colleges and universities. There are at present a few vacancies, which it will be desirable to fill with youths whose educations are intended to be on a liberal scale. In announcing the intention of resuming the duties of their vocation, the subscribers tender their acknowledgments to their patrons for the grateful sense which they manifest of the im- provement of their sons and wards. As to the general charac- ter of the institution, reference is made to Professors Bonny- castle, Harrison, Emmet, Tacker and Davis, of the University of Virginia. , The seminary is easy of access to students coming from the North or from the South, being situated about three miles from the Richmond and Fredericksburg Railroad. Letters addressed to either of the subscribers, and directed tol Concord Academy, Caroline county, will be promptly attend- ed to. A. C. COLEMAN, F. W. COLEMAN, dec21--d&clm J. D. COLEMAN. N EW BOOKS.-The Youth's Letter Writer, or the EpiEtolary Art made plain and easy to beginners, through the examples of Henry Moreton. By Mrs. John Farrar. The American Frugal Housewife, dedicated to those who are not ashamed of economy. By Mrs. Child. Three Experiments of Living: Living within the Means, Living up to the Means, Living beyond the Means. Sequel to Three Experiments of Living. Stories from Real Life, designed to teach true Independence and Domestic Economy. A fresh supply, just received and" for sale between 9th and 10th streets, Pennsylvania Avenue. dec 18 R. FARNHAM. V IE DE WASHINGTON.--The Life of Gen. Geo. Washington, in French, by A. N. Girault. For sale be- tween 9th and 10th streets, Penn. Avenue. nov 3 R. FARNHAM. C ASH FOR NEGROES.-I will give cash and liberal prices for young and likely negroes of both sexes. I can be found at Mr. Thomas Lloyd's steamboat hotel, on Seventh street, opposite the Centre Market House, in the City of Wash- ington. All letters (post paid) will be punctually attended to. jan 10-eo7t JILSON DOVE. B RITISII DRAMA, in two large octavo volumes, hand- somely printed, and well bound, with engravings, con- taining one hundred and twelve of the best Plays in the Eng- lish language. Price$4 50, (equivalent to about 4cents for
each Play.) For sale by
jan 10 F. TAYLOR.
F-RESH GARDEN & GRASS SEED STORE,
at the old established stand, M'Mahon's, 17
south Second street, Philadelphia.-The subscriber in-
forms his friends and the Public generally, that he has received
his new crop entire of Garden and Grass Seeds, which he war-
rants to be equal, if not superior, to any articles of the kind of-
fered to the Public.
He has also for sale, at his Nursery, on the township line
road, above the first gate on the Germantown turnpike, a choice
collection of Fruit and Ornamental Trees, many of tlhe latter
suitable for street planting, together with a great variety of gar-
den shrubbery.
Also, a choice collection of Double Dahlias, which he will war-
rant to be true to name and color.
Also, several thousand Macluras, or Osage Apple, or Orange
Trees, suitable for hedges, together with a great variety of hot-
house and green-house plants, all of which will be sold asrea-
sonable as they can be purchased in any part of the United
States.
Orders left at the store, 17 south Second street, or the In-
dian Queen Hotel, 15 south Fourth street, will be promptly at-
tended to.
doc on-on.n ("ln ( TiFTRNAR nt nTTiTK
Elegant black Lace Veils
do Edgings
do Insertings
Swiss Edgings
S do Insertings
Muslin Bands
Superior Linen-Cabric Handkerchief
r.i Book and Swiss Muslins ". ~
Colored Straw Bonnets, &c. -
jarrJ6-3t \VM & GEO. STETTINIUS.
r O THE LADIES OF WASHINGTON.-Mf .
S BLAKEY, of Balrimnore, corset maker, from hlndon, "I'
exhibit her celebrated Corsets for sal., for a fewday, cotiN
menacing on Tuesil:iv, the 16th in-r. at Miss Artridge's, dreds
maker, over Mr. Beardsley's conrcclionary store, Pepnniylvani4
avenuee, -ineir 12th street, where the ladies may avail thefI,
selves of the opportunity .o purchase. .-
jan 13-3t .
ALE OF-GENTEEL FURNITURE-By Ed-
S ward Dyer.-On Fri-ay next, the 19th instant, at 11
o'clock A. M., I shall sell, at the residence of Mr. Sairhel L.
Willkon, on Calitol Hill, B street north, near the residence of
Colonel Williamn Brent, the furniture ofhis Boarding e;lablihh-
menl, consisting in paro-f-- -
Mlahogany Side*oard, Brass Andirons and Fenders
Cane-seat and il6ter Chairs, gilt set Dessert China
Cut Celeries, Ivory handle Knives and Forks
Handsome Tureen, &c., Damask French Napkins
Hall Lamps, pas.sae and stair Carpeting and Rods ,
With high-post and French Bedsteads, very superior Beds,
made in thelefimuly, Mattresses, Marseilles Quilis, Blankets and
C'uonfortatles, of best quality; with several excellent Chamber
carpetss Bureaus, Toilet Glasses, Washstands,,Basins and Pit-
chers, with many ohibr articles desirable to housekeeperxsand
'mnot necessary to lie enumerated.
There will also be added, a first-rate double-barrelled Fowl-.
ing Piece, and an excellent Violin.
Sterns ofsali : For all sums ofand under $20, cash; over W90, a credit of 60 days; purchasers giving notes, with approved endorsers. EDWARD DYER, jan 16--TuTh&P Auctioneer,-' ENTEEL FURNITURE. Ad. by E. DYE., On Thursday.-ne., the I1th in-tant, at II o'clock A. M. 1 shill sell, at the resid nce of the Rev. Mr. Hanson, "n 10th street, between ) naid streets, [east side, all his hosehd an,] kitc hen Furniture, coisisiing, in part, of excellent 'ii -grain parlor aiid chamber Carpets and Rugs, and cane-s"- land otlhed Chairs ;IAndiions, Shovels, Tongs, and Fender; handsome mantelPilass; straw Matting, &e. ; an excellent eighlt-dav Time Piece; iah.,gan.y Tuubles; step C'arpet aTfi Rull ; French-post maple Be'.lIseard, excellent Beds and Bed- ling ; Bureaus, toilet Gl;ses, Washistann Basins, atl Ewers; \Waidrube, &c. with a good assorltmlent of kitchiln utensils, aiio,nst them an excellent Cooking Stove, (te- plate,) withl two boilers, large size. Also a lot of \Wood in t e yard. Terms at sale. EDW. DYER, _ .-jan 16-3t Auctioneer. ',T HE Subscrihbr will rent the house in which he at present sides. It is situated on the corner of G6tha ad D streets, atid is iminediately we. t of tlh' Unitarian Churdh. The house is in a very pleasant neighborhoodand has ev 4v convenience attaclied to it wliii-h could be desired. It is tihoujpt. unnecessary to give a larticil.ir description asthe person wih- ing to rent would view the pretuisi.i Toa careful andpuncta'pl i.:-nant, the rent will be modcrati-. i'or furtherparticulars apply at ithe City Hat to o WM. HEWVITF., S'an 1t-3t (Ghe) A BOLMAR'S INSTITUTION 'OIL BOYS, *. est Ch(ester.-Ti4 above school, fo.r the ediiuafldn and instrtuction of Boys, is located in thle berough of \Wesi-Cles- ter, Chester county, Penn., within about,"Ifor hours' rid4 of Philadelphia, by the Columbin Railroad. * The biiillii;is. have been planned and completed expressly for a Boarding School. The school has been in full operation since May, 1834. The number of boarders has varied between sixty and eighty, from different parts of the country, principally from Philadel- phia, where A. BOLMAR has been known as an instructor of youths for many years. The pupils are advanced, as rapidlyas their intelligence per- mits, in the knowledge of such branches as fully prepare them for college or for a mercantile life. The most particular attention is paid to the morals, health, manners, and personal neatness of the pupils. No boarder is ever permitted to leave the premises without permission. No new pupils are received over fourteen years ofage. As there is in West Chester a place of worship for almost every religious sect, pupils are accompanied or sent on Sundays to any one that parents or guardians designate. The school year consists of four quarters, of eleven and a half weeks each. There is a vacation of three weeks in April, and another likewise of three weeks in October. If desired, any boarder may remain at the school during the vacations. The course of instruction comprises Orthography, Reading, Writing, Arithmetic, Gepgraphy, the use of the Globes, Eng- lish Grammar, English Composition, History, Book-Keeping, Algebra, Geometry, Mensuration, and Surveying; the Latin, Greek, French, panish, and German languages. During the winter, Lectures on the Elements of Natural Phi- losophy, Chemistry, and Astronomy, are delivered to the pupils at such time as does not interfere with their other studies, aid by this means they get some valuable information during a time which is generally spent in idleness in most boarding schools. The charge for each boarder is$250 per annum, payable quar-
terly in advance. This sum is in full for tuition in all the above
branches-except in French, Spanish, and German-for Board-
ing, Lodging, Washing, Fuel and Light, including also the use
of Bedding, Maps, Globes, and of Books for reading.
Pupiis studying French, Spanish, or German, pay for each
$50 extra per annumn. Drawing$10 per quarter.
The Principal is assisted in the discharge of the duties of his
school by Messrs. H. B. PEARSON, JAMES A. KEECH, THOMAS
COSOGOVE, CHAS. BURTON, LouIS BEER, M. GOLE, and F. LE
BARBER.
REFERENCES.
In Philadelphia.-Rev. Samuel B. Wylie, D. D., *A. D
Bache, Henry Reed, Professors In the University of Pennsylva-
nia; Charles Picot, *Matthew Carey, *S. Jaudon, *Peter Gra-
ham, *Gerard Ralston, *Ashbal Ralston, A. de Valville, Robert
Walsh, Esquires; *Professor Walter R. Johnson; *John IM.
Brewer, M. D. ; M. E. Hersan, Esq. French Consul; *John
Swift, Esq. Mayor of Philadelphia ; Hen. John Sergeant; *Hon.
Joseph Barnes ; John K. Mitchell, M. D. ; Peter S. Duponceau,
*H1. D. Gilpin, Henry Toland, *S. C. Walker, *John Frost,
*Manuel Eyre, Esquires ; James Rush, M. D.; *Hon. George
M. Dallas; *John M. Scott, Esq.; George McClellan, M. D. ;
S. Calhoun, M. D.; Professor Jacob Gieen; *John M. Read,
*Clement C. Biddle, *Moses Kempton, Esquires; *Hon. Win.
Dunne; Colonel Wm.Drayton; Charles J. Ingersoll, Esq.;
*Wm. Gibson, M. D.; *Robert E. Griffith, M. D.; J. J. Van-
der Kemp, *Colman Fisher, *P. J. Van Hall, *Isaac Harvey,
*Wm. Read, *Henry C. Carey, Esqrs.; Samuel Jackson, M.
D.; Philip M. Price, M. D.; John Bell, M. D.; *Isaac Lea,
*Jacob Gilliams, *Isaac Roach, John Laval, *Charles Chaun-
cey, Joseph R. Ingersoll, Esqrs.; *Isaac Hays, M. D.; N. Shoe-
maker, M. D.; *General Patterson; *Joseph G. Nancrede, M.
D.; Eli K. Price, Esq.; *Thomas Harris, M. D.; *Algernon
S. Roberts, *Henry White, *John Stewart, *Wm. B.Fling,
*Durden B. Carter, Esqrs.; *Col. John G. Watmough; *Con-
dy Raguet, *Thomas U. Walter, *Samuel H. Carpenter, *L.
Kimball, Esqrs.; and *Pablo Chacon, Esq., ConsulGeneral of
Spai n.
In Burlington, N. J.-Right Rev. G. W. Doane, D. D.
In West Chester.-*Wm. Darlington, M.D.; *Ziba Pyle,
Esq.; Isaac Thomas, M. D.; *John W. Townsend, *David
Townsend, *Nathan H. Sharpless, *Townsend Haines, Esqrs.;
*Wilmer Wortlington, M.D.; *W. H. Dillingham, Esq.
In Pittsburgh.-*Hon. T. B. Dallas and *H. Bonnet, Esq.
In Washington, D. C.-Wm. S. Derrick, Esq.
In Virginia.-*Wm. Burke, Esq., Red SulphurSprings.
*John Dunn and *Benjamin Jones, Esqrs., Petersburg.
In Charleston, S. C.-Dr. Wilkinson.
In Georgia.-*Hon. Langdon Cheves, *Isaac Minis, *M.
Myers, *Robert Hazlehurst, *Peter Wiltberger, Esqrs.; Geo.
Jones, M. D.
In Louisiana.--*Hugo C. Gildemeester, *Richard Bein,
*John D. Bein, *Wm. McKean, and *Henry McCall, Esqrs.
N. B.-The Principal of the institution here announced either
taught in the families of the above named gentlemen before
whose names an asterisk (+) is placed, or had some of their
T HE CHRISTIAN-STATESMAN, deroted to -the
promotion of just riews in' Liter'lure Humanity
'Liberty, Politics, African Colonization, and Reigion.
The Rev. R. R.GiUR.Ev, Editor. ..
'The untler-igded propose to establish in the City of Wash-
.ington, under the'editorial direction of the Rev. R. R. Gurley,
a weekly paper, ad'a'pted to p~inote just views in llorals, lIan-
ners, Gorernment, and Religion, and which, sel arate from
the selfish conflicts of ambition, and the uncharitable controver-
sies of sectarianism, shall contribute to unite all Patriots and
Chjistians in the accomplishmid'nt of objects for the good of our
country, tile benefit of humanity, -and the glory of God. It
will be our endeavor, through the aid of our able and efficient
editor, to make this journal woithy- the patronage of the Amer-
ican People. The cause of African Colonization willbe ad-
vocated as meriting the united, immediate, earnest, and liberal
support of this 'nation. A summary of general intelligence
will be given weekly; and, during the session, a condensed re-
port of the, proceedings of both tHuses of Congress, pid a brief
"iew of public. affairs. In fine, no means will be neglected of
presenting to the Public through the columns of the Statesmani
such information, facts, and argumemnis on the topics which
most occupy the minds of the wise and good-in this country,and
age, as may tend to advance the great .nse of human im-
provement and happiness, and render this joupal in every re-
speot a valuable family newspaper. -
CONDITIONS. '
The CHRISTIAN STATESMAN will be published in the City of
Washington, every Friday" morning, ou an imperial sheet, at $3 per annum,'payable in advance. Individuals ra.nsmitltiing the amount for fiie or more papers, shall receive them at$2 50
each, per annum.
The first number will be issued in the first week in Februa-
ry, 1838.
'- All communications relating to subscriptions, and the
-financial affairs of this journal, to be addressed to ETTER &
BAYNEr pulishers Of the Christian Statesman, Washington
City, D. C. Those relating to, the editorial department; to the
Rev. R, R, GURLBj, editor, &c.
JOSEPH BETTER,
dec 30- VILLIAM H. BAYNE.
OYSTERS, TERRAPINSS, AND VENISON.-
Tie subscriber has just received a large supply of re-
markab'y fine Newark Oysters, to which he invites the atten-
tion of lovers of ihis delicious shellfish. He has also got some
immense Rockfish, tle finest ever brought to this market.
His larder will be lieund well sIuplied with Terrapins, Veni-
son, and other delicacies. J. BOULANGER.
jan fl--3t (Globe)
NE E M MAHOGANY FURNITURE, MANTEL
alid Pier Glasses, Piano, &c.-I have just received
for private sale- .
3 liew mahogany Sideboanrds
Several new mnilaogany iniletand plain Bureaus, '
Secretary, and Bookcase,
I dlzen mahogany hair seat Chairs,
2 Jozen maple cane'seat, do
Mahogany dining and card Tables,
,A beautiful maple centre Table,
,- l-Hair seat Sofas, new and second hand,
One new and one second-hand Piano-Forte,
Large gilt mantel and pier Glasses, French and
-.German plates,
With a great variety'of mahogany mantel and pier Glasses, all
sizes, all of which will be sold.at redlnces prices for cash. A
few sltares National Theatre Stock, fully paid up, for sale.
EDWVARD DYER,
jan I.l--3t Au.tironeer and Ctnniksion MNrlPhani.
OUGE ON BANKING.-A sliwrt history of"l,'per
money and baking in the United States, including an
"account of Provincial and Continental paper money; to which
is prefixed an inquiry into the principles of the system, &c.
Also, an inquiry iato the expedicncy'of dispensing with bank
agemny and 'bank paper in- the fiscal concerns of the., hited
States. By Win. M. Gouge. .. ,
A fresh supply just-received and for sale, between 9th and
10tl streets, Penn. avenue. R.-FARNHAM.-
jan 15
"HISTORY OF THE LATE WAR-Comprising
A a minute account of the various military and naval oper-
ations, with many engravings, one volume, is just received and
for sale by F. TAYLOR.
Or for circulation among the subscribers to theWaverley Cir-
culating Library. jan 15
CHOOL BOOKS.--The subscriber is constantly re-
ceiving from the publishers, at the North, a great variety
of School Books, in every department, and which will be sold
at the same prices as if bought from the publishers.
Parents and teachers will find it to their advantage to examine
the books, and a liberal discount always made when bought by
the quantity. R. FARNHAM.
At the School ancFJuvenile Book Store, between 9th and 10th
streets, Penn. avenue. jan 15
the laboratory of the original inventor Laroque, and for
sale at the old Snuff, Tobacco, and Fancy Store, between 11th
and 12th streets, Pennsylvania avenue. L. JOHNSON.
P. S. A general assortment of fresh Perfumeries, Toilette
Soaps, &c. for sale at the lowest prices, as above. jan 15
FLOUR, CORN, &c.--
S 200 barrels Flour, Clagett's brand,
300 do do different brands,
1,000 do Corn,
3,000 bushels ground Alumn Salt,
800 tons Plaster,
In store and for sale by W. SMOOT,
jan 15-7t Georgetown.
4nfHIS IS TO GIVE NOTICE that the subscriber
.-B hath obtained from the Orphans' Court of Charles
county, letters of administration on the personal estate of
Henry Davidson, late of Charles county, Md. deceased. All per-
sons having claims against the said deceased are hereby
warned to exhibit thesame, with the vouchers thereof, to the
subscriber, at or before the 20th day of August next; they may
otherwise by law be excluded from all benefit of said estate.
Given under my hand this 5th day of December, 1837.
JOHN H. DAVIDSON,
dec 9-w4w
FJ1 HIS IS TO GIVE NOTICE that the subscriber
has obtained from the Orphans' Court of Washington
County, in the District of Columbia, letters of administration
de bonis nor,, with the will annexed, on the personal estate -of
David Bates, late of Washington county, deceased. All per-
sons having claims against the deceased are hereby warned
to exhibit the same, with the vouchers thereof, to the sub-
scriber, on or before the 5th day of January next; they may
otherwise, byllaw, be excluded from all benefit of said estate.
Given under my hand, this 5th day of January, 1838,
DANIEL C. DIGGES,
jan 6-w3w Administrator D. B. N. W. A.
l LOUR.-100 bbls. white wheat Family Flour, very su-
perior,
85 bbls. Pennsylvania mountain wheat Flour,
300 do. superfine Flour, most approved brands,
100 do. scratched or fine Flour.
In store, and for sale by W. T. COMPTON,
jan 11-w3t Water street, Georgetown.
3 hhds. and 5 bbls. Whiskey
4 bales Marseilles Almonds
2 do Euglish Walnuts
2 do Filberts
8 baskets Champagne, key and other brands
10 kegs prime Butter, Baltimore inspection
200 Shenandoah Roll do
Citron, Raisins, Currants, &c.
For sale low by
A CARD.-As persons shall receive their accounts, they
will please call and.settle them, as it is particularly de-
sirable that all accounts should be closed, either by note or
otherwise, before a new one is opened for 1838.
H YMNS, selected from various authors, with a Key of
Musical Expression, by Samuel Worcester, D. D. Also,
Watts' Psalms and Hymns, with the preceding selection add-
ed. For sale, between 9th and 10th streets, Pennsylvania ave.
dec 8 R. FARNHAM.
DEBATE IN THE SENATE.
jSAt RDAY, JANUARY 6, 1838.
ON MR. CALHOUN'..RESOLUTIONS.
'The-resolUitions of Mr. CALHOUN., on the relations, &c.
of the State and General Governments coming up, and the
question being on Mr. MoRRis's amendment to the'third
resolution, declaring the freedom of speech and the press
oni all subjects indisputable, and under the supervision on-
ly of the State in which such freedom is exercised---
Mr. MORRIS resumed his remarks by say-
ing that the error which he had committed the day before,
in relation to.the,sentiments of the Metliodist Conferen6i.
had afforded so rhuch pleasure, that he did not regret hav-
ing fallen into it.- He made a brief explanation, which
which was believed to relate to this mistake, (but inaudi-
ble and unintelligible to the reporter.)
What, he asked, was the object of the resolutions un-
der consideration ", It was to restrain and check the liber.
ty of speech and of the press, and their first amid principal
domination was now felt in the Senate. But, he repeated,'
that the attempt to stifle the freedom of speech and the
press in this country, on moral or political subjects, would
be a vain effort. But ilit Wfas sinful to discuss the ques-
tion of slavery, or other subjects relating to other commu-
nities, he asked why they did not. attempt to suppress dis-
cussion by an enactment. If it really threatened a disso-
lution, it deserved the severest measures that the Senate
could adopt against it. Why then not put it down by law
at once!' Let us see the features of such a law, and then
form our judgment respecting it. Would the People sub-
mit to it? Would any man dare to make the attempt
There was no Government in the world that would dare
to do it openly and generally.
right of a slaveholder'to his slave. The Senator from In-
.diana had said, and it had not been denied, that one effect
of these resolutions was to extend slavery. Mr. M. re-
sponded to that sentiment; and this was one object, if there
was a-ny object at all. But if the Constitution of the Uni-
ted States was held to guaranty the property in slaves,
then that Constitution was, on thispoint, above the law
and Constitution ofvany State, and the act of no State,
therefore, could annul the property in slaves. [" State, un-
der the laws thereof."] Mr. M. had used this argument
before, and it wouldTollow fromit that the States were
all still slaveholding States under the Constitution, and
must continue so, beyond the power of this Government,
unless the States generally should give that power.
The Constitution, therefore, Mr. M. maintained, had
left slavery precyely where it found it. But the framers
of the Constitution had intended that the moral power of
this instrument should abolish slavery in all the Starts, and
accordingly the States began immediately to abolish slavery
on its adoption. The ordinance of 1787, in relation to the
northwestern territory, was adopted by Congress at the very
time when the framers of the Constitutiorn were sitting in
Convention, and the Constitution was adopted two or three
months after that ordinance. Now, could any one believe,
while Congress, in the very face of the Convention, deter-
mined t-hat slavery should'not exist in that vast territory,
that they did not intend that the moral .power of the Con-
stitution should abolish slavery in the whole country 7?
Mr. M. went on to argue that, by the Constitution,
Congress has the power to abolish slavery in the whole
Union. More than twenty thousand- citizens of Ohio were
the friends of emancipation; and he thought, when these
petitions came up here, they did not deserve the treatment.
they received of being called incendiaries, aid being brand-.'
ed wjrh infamy.- the objef
Mr. M1. concluded by explaining theobjecthfhishiend'
ment, which was (he said) to enlarge more fully that which
had been offered by his colleague (Mr. ALLEN.)
Mr. PRESTON said he could see no shade of difference
between the two amendments.
Mr. HUBBARD called upon Mr. MORRIS to point out
the difference.
Mr. MORRIS said, ifthe eagle eye of the member from
New Hampshire couldn't discern between thetwo, it
would'be a hopeless task for him to enlighten him.BEut, he
would ask, if Mr. HUBBARD could see no difference, why
was he so much opposed to his, while he was in favor oftthe
other?
Mr. CALHOUN suggested to Mr. ALLEN to withdraw
his amendment for the present, as only tending to embar-
rass the general question, and to consent to introduce it at
the end of the resolutions.
Mr. ALLEN assented; but, as the, amendment could
,not now be withdrawn but by unanimous consent, it was
agreed that a vote of rejection should be taken on it, pro
forma, that it might be offered by the mover hereafter, when
all the resolutions should have been acted on. The vote
being accordingly taken, the amendment was negative.
Mr. DAVIS then urged the propriety of Mr. SMTHn's
amendment being now taken up. It appeared to him the
object of Mr. ALLEN'S amendment had been to get rid of
the other; and now that it was withdrawn, he thought the
question ought to be taken on the amendment first offered
by Mr. SMITH, of Indiana.
The question, however, being announced from the CHAIR
to be now on the third resolution-
Mr. PRENTISS rose, and said that, as the re-
solution under consideration had been considerably modified,
and rendered somewhat plausible by amendments, he wish-
ed to say a word or two before the question was taken up-
on it, in explanation of the vote he should give. He had
been offered, and should feel quite indifferent as to the/fate
of any amendments which might hereafter be proposed,'be-
cause it was his intention to vote against all the resolu-
tions, without any critical examination into the truth or
correctness of any of the propositionscontainedin them. He
should do this not only for the reason which had been fre-
quently stated, that the vice of nullification was apparent
upon the face of the resolutions, but for another reason al-
so. It was obvious that they could neither add to nor
abridge any of the constitutional rights of the People, by
any resolutions they could adopt.; and he deemed it not
only unnecessary and useless, but highly inexpedient, to
make a formal declaration of rights there, to assert abstract
principles, in the form of resolutions, having no view to
any practical results, and which might not only be liable
to misconstruction and misapplication, but might occasion
thereafter as much controversy as to their meaning as did
the famous Virginia resolutions of '98. He did not wish
to go into the subject at all, but merely to say that he
should vote against all the resolutions, because he consider-
ed most of them wrong in principle, and all of them unne-
cessary and inexpedient.
Mr. DAVIS next rose. He said that he had
several times briefly addressed the Senate upon this sub-
ject, which for two years or more had been greatly agitat-
ed, more so, probably, than was useful. As ling ago as
that, an effort was first made to suppress petitions upon
the subject of abolition in this body, and from thence till
though both here and in the other House much regret had
been expressed that it was agitated at all.
At the first session of the last Congress, after a long,
animated, denunciatory debate, carried on chiefly by the
members from the South, the Senate arrived at certain re-
sults in regard to abolition petitions, in which he (Mr. D.)
did not concur, but a very great majority did. It was pro-
per to recur to the state of things then, and to call to mind
the sentiments of that day. The leading argument in that
debate was, that the agitation of the question was a source
of great danger, pregnant with ruinous consequences to
the country, causing serious obstruction to t;he action of
Congress, and great uneasiness out of doors. And it was
most urgently insisted that it was one of those delicate to-
pics which it was not safe to discuss, which, in truth, we
had no right to discuss, either as regarded the States in-
-, - '. 'i .
is, that the ne presenting the petition d ed c i t hS
to lay it before the Senate, as the Sma fed tecetv
it.T'he Senatoufrom South Carolina COA touer w) s
jn the lead of these measures, and is it:ot true that hec aI
sustained by an overwhelming majority 1 -.' ''
Mr. CALHOUN said the'towsve whieh Ae marked olyt a
not followed at all.. .. .
Mr. DAVIS. I did not mean to say that thedJ lt'of&.d
Senator's proposals was adopted but, that the Senate at
trained the chief purpose he ainied at. .
Mr. CALHOUN. I was in the minfority in every vote i"
This subject. 1 wished to, meet the petitions, a&d i~a
the admission.of them. I wished to talkeiigher ard it
er ground. I was ndt-averse to agitation. .
lr. DAas. I did not allege that thtfenatir wao~ "Si
to agitation, but that it was gene a eeatedand thai
his proposed measures looked to th -eni 'aie'the Piaran
irost fully proves.. If the Senator bhail not ief~rIid
he would.have had no occasion to complaliUr- t&o nwt .
me4for I 5 about to notice what I am aware of, h.B
pripbed'urae of the iemiber was to meet theilme- 'W
era at the' do*, shll' it -in their faces, turn thd rf
stairs, and bil hi ne; andthat he Urged ,tAiI .
to sustain t.itt iew of tht matter., In t'afl kni
was failure; Hiit in liisgeneral oblct ithMb
by different meaqi,. he tid fully suCpeW. He.
friends did erect a.. bairLer 'i iaih asle
barrier insurmountable t9 te tltioCB ani[ Uilf tall
to stop agitation and debate iq this ch srer;-and the pre-
sentation of petition,1 ast cWioi tle: lt| _feot bili-t
ties. Discussion died wvjthi'hi~ arbitrar a"ethe
Sena4e yielded obedience to it. If any t iph ist-
portaice had since been said', it hai escao betpya*
lion. I therefore repeat that 3he oljeet of the tiiafh r,had
been attained ; the pelitionervJlave bee friivtll; i iy-Wt -
out 9 hearing; ,po aspweri-o tir pra.r J.a .ben.ls-4
no, not so' mui h as to say tiey were in $ir.' W~h I.. .wouldask, cquld the Senator -do beond thws, if th Bti- ate yielded itself tQ his will ' TffSenator from Viginia (Mr.Jl, i said yytdy, that the States could take care of,.me.elvif %ti' .B nel through this Goverin-t waa u pfftt. f, 4 nothing from th.aibolitjnt s i i.b own teirt Q . not the Senate close up tbhis ha eouguetai6 ly '. it not choked to the top,. e s ht~ inhg can eahn Se Senate ? What higher or str~ner baier i can b 1 pmft There is but one-that can be more-effeetal, and that is, t, make a law of Congress, consisting-of pains amd.peamlties..: Make it felony, punishable by'imprisonment in t '- i-. tentiary for any one to p"fition fbr the abolitionfbf l rey in this District. If therd be nb right to petition, antr the pe- titioners arikviolators of the Constitution, ddtturber b6f'ihit . public peace, criminal agitators, threatening.tihe Afety'od- the Union, t heauch a lawwill be 4th isittioIh ft expedient.* Let it be brought fofw'~t, fdr it, itl'teg ti. principles advocated, and jpt memlbeis to vote upoli'A. - ponsibility beyond a n'eK ex prespion ofpinnm. fe o I such offenders against the pdblie peaca "libli. jita' to the judicial tribunal, if such is:the scie of Otgrhm , to receive the reward of thehirmerits. T4ts would f stamp of cortsiste iAy. J thiabctiinei 'rc temnfti 6lth results are sound, 'eri 'let -them gotoirth in a.fordthlra shall he undersoo& ld lel.',- Lel those whe deiimnrat li I take thd re ~ I oassaa ~eir hands, ahd they itff soon learn t'h ieosf of t e-blie on this right orpftfidn. This would be nore manly than to agitate the PCabl icf threats.. It wol.l fence the People out from the Capit,; and separate tem from their own Goyqnment. Jt Il o1lt consign ofenfc to infamy foz .Besumutiuousy daring to l,4proach ehallst to aike a humble request. T'h sen- or h'asTot prl ed 6 this len'dth; and irtihgh he 4s qit ri in, isying he was in a minority, yt it i 'obvit th 3tf his main -bject.. Pelitns con- tinued to co rihFreutndo what end .1-N-elah t-q tR-- heard, nor received. Not one has since come to the'posses- sion of the Senate so as to be in order for its action; nor, under existing practice, could one corm-to its posseuruon. In this state of things, why are wLe appealed to for'new- measures, which can do no more than accomplish the same thing, if they do as much 1 Why does the Senator from Carolina, when so solicitous to exclude from those ihalls the petitions-when he has steadfastly maintained that: Congress has no right to debate or act on the subject-whby does he voluntarily introduce it here ? A stuject'too deli- cate to-agitate;, one which, it is said, we-oughl not to difs cuss, and have no right to consider! Why then is dii- cussion invited Why is examination provoked? hy is controversy challenged? ' For myself, said Mr. D, I have been disposed to respect the avowed feelings of Southern Senators; and as they - seemed to deprecate discussion as a calamity, I have avoided it, leaving it in the hands of the mover and those interested. I had no purpose of changing my course till that Senator, yesterday, threw down the glove, and challenge l discus- sion, in terms which almost made it dishonorable tb forbear. This challenge, and this alone, has induced me to rise, for I had resolved that the Senator should be left free to act upon the majority, which goes with him, with' whatever power he might, while he adhered to abolition, although my own constituents have written to me inviting my at-. tention to these resolutions; not because of their effect upon the abolitionists, but because they embrace other matters of high moment and of objectionable character. I would have taken the hazard-of disregarfling these calls upon me, but I could not be silent under the challenge of ^ the Senator. The Senator says we can bring no objection against his resolutions while we vote against them, inferring from our silence that we vote il, a blind and senseless-manner. I deem his inference, from his premises;' wholly unwarrant- ed, for the larger portion of the votes we give are recorded without offering the reasons to the Senate.upon which they rest. But I have many objections to these resolutions, more than I shall find physical ability to express, and the strong- est of those objections are to their political character. They are not called for, are not more efficient than the measures now in force, and can do no good. They are, as has beeinwell said-, (a part of them, at least,) mere abstrac- tions oi"avowals of abstract doctrines no way demanded by'. the occasion. They embrace matters having no connexion with abolition, and call upon us*to commit ourselves, to an interpretation of the Constitution when there is no emer- gency arising in the course of our public duty requiring us to give interpretation to that instrument. Jt is an unne- cessary attempt to influence the public judgment, and such -4 works of supererogation are best let alone. Any and all these reasons are a most ample justification for voting against even that which may seemito be right in the abstract; for I would give no countenance to making a creed of avow- als for politicians, and to the publication yy. the Senite of abstract opinions, merely because they may contain appa- rent truisms. They ought also to be useful, and put forth for some useful public purpose. The Senate wouI wbe foolishly employed to. resolve that two added to two make four. But, sir, the leading reason urged for disposing of the whole abolition matter is, that the agitation of the topic dis- turbs the public harmony and endangers the Union. I am quite disposed to respect all such fears and apprehensions, when urged with seriousness, to listenito public sentiment, and to yield much to public judgment; and, sir, I am happy to perceive that the. thought now and then flashes across the minds of gentlemen that there- are two ends to this Union, both of which should fall under the protection -and paternal regard of this Government. We are the represen- tatives of the whole, and our affections and watchfulness should be commensurate with the whole. It is,our duty to see that the whole republic is safe. All interests must be regarded, all rights must be, protected. We must look to i lblic sentiment throughout.- No interest, because it is great and powerful, should be permitted to absorb all public attention, or to cause a disregard of those of less importance. All must be nourished, all respected, the rightswof all so adjusted and harmonized by a spirit of compromise and con- ciliation as to remove all just cause of discontent. This is th ..... t, o Tir~lrve the Union. And vet. from the course - -* l ^ ; ,:':' .. '" .-\. ^ ,+ .*; ^ ; ** .+ w ... ,2 L . 4o&tm& -~~~ , -J *2~ * 1. Vat. XXVI. _ _.w,% % u r it... v i d% x c, -* .4 '. A A - .. I O S-- -.. ** __ .* . =5 -. '^ o .1 r7' . ^ ~ ~ ~ ~ ~ ~ r *'-. -''' ."^ t- ."*l n m Sho f, political Power, or those who ave no pE except the rce of argument' 7 J wish to ask you, sir, what your llqctions are re- jd to the history of public policy. T have probably- fr the last thirty years been a witness and participatory in what has occurred here, and your memory can go much be- yond that. You know what has been the public feeling on the subject of the integrity ofthe Union, and what kind of a reputation those have acquired who have been suspected only of agitating this alarming topic. How stands the Hart- ford Convention in public estimation?- How other coin- ventions and assemblies of men of more recent date, who were supposed to meditate unfriendly feelings to the Union ' All hostility to the Union has at all times been viewed by the great body of- the people- with the most profound sor- row and regret. ThosiL therefore, iho" engage in such treasonable purposes, do it at the imminent hazard of charac- ter, at least, for.they acquire a very unenviable reputation. The abolitionists can have no motive 4o dissolve the Union. They have never been charged with such an ob- ject, to my knowledge. Their acts may create alarm and discontent, which may-tend to that. There may be sel-- fish men among them, for the ambitious always mould the moving elements, when they can, to aid 'their own selfish purposes. It would not be singular if such were found among them, but their number cannot be great. But how is the abolitionist to be profited, if his wishes are all realized ? If all the slaves on the globe were made free, how will it mend his condition ? In no way whatever. SHe can gain nothing by the change. But they repudiate, and very properly,-all right to interfere with the States, and confine themselves to the Territories and the District Sof Columbia. Their views are thus'limited in extent, and to the attainment of an object in which they neither have nor can havd any interest which excites a selfish feeling, and which does not, in fact, touch the Union, or threaten it. :.The worst, then, which can be said of them,' by their bitterest enemies, is what is actually said: they are de- luded, misguided philanthropists, fanatics-heated with an unbecoming zeal. These, and such opprobrious epithets, have been applied to them; but no one affirms that they aim -at disunion, nor do I think any one can impute to them any corrupt purpose, I do not-~iean to touch the question of the expediency of their course in asking for immediate abolition in this District. That I will meet Whenever the Senate will open it by receiving their peti- tions, but riot until then; for the right of petition is the higher right, ,rnd must first be vindicated. I shall,'how- ever, at all times'go for the Union, and the whole Urtion; and against the abolitionists if they propose to interfere with constitutional rights or guaranties. But I again return to the inquiry, who is to dissolve the Union ? There cannot, I.trust,.be such purpose here, for 'every day we hear the thought deprecated, and the depre- cation mingled with the most ardent patriotic professions of love an attachment to the Constitution. Is the great ,slave interest to do it ? I appeal again to your recollections, and to those of the Senator from South Carolina, and ask you whether an interest, so powerful as to have majorities in both Houses,and to maintain its 'ascendancy in the Govenaient, is likely to have occasion to secede from the Urri.n through fear or oppression? Sir, this interest has raled the destinies of the republic. For forty years out of forty-eight years it has given us a President from its own territory, and of its own selection. I do not advert to this in the tone of complaint, for it has been done at the ballot box; but as a proof of its great :strength, tact, and skill, and of the extraordinary predo- Aminance it liolds'over all other interests, bending and shaping them to its purposes. -During all this time it has not only'had a President sustaidiing its own peculiar views of public policy, but through him has held and used, in its own way, the whole orgaiizdatltipof all the Departments, and all the vast ai cootrolfiijg patronage incident to that office, to aid it at"idcarry out its views and policy, as well as to protect it and secure to i~ every advantage. Let us explore' little furter, sir, ~nd see how the Houses of Congress have been organized. I. qm sorry that I rely on memory alone, for- I may possibly, fall into error; but I shall be, I think, right as far is 1gp; if not, the records can easily be had to correct m*.' ,For thirty years out of thirty-six years, that interest has placed its own Speaker in the Chair of the other Hotiltethus secur- ing the organization of committees, and theW g_ tinfluenee of that station. Ad;-,sir, while all other interests have, during part of the'i ie, had the'Chair in Wrih 'you pre- side assigned to them, as an 'eqiivalent'to'r thesegrea; concessions, yet in each year, when a president pro terni. is elected, who uon the contingenet~s meft'iped in the C'-be the President of the United States, that interest has invariably given us this officer. Look, I besee~ h you, through all the places of honor, of profit, and privilege, and there you will find the representatives of this interest in numbers that .indicate its influence. Does not, then, this interest hold the destinies of this re- public in its owni hands l. Does it not rul< guide, and adapt public policy to its own views, and fit it to suit the action and products of its own labor ? Sir, I know that the politicians of the slave country sometimes disagree "about men and; measures of minor consideration ; but, on thygreat inter4tt of slave labar and th.i protection of slave property, they- tand firmly together, aiil, like a Mace- donian phalani, shoulder to shoulder, gather round it, and, by mighty and concertd efforts, give it the lead in public affairs against all opposition. Sir, how can I better explain its all-pervading influence than to declare again "i iiftnloves this Government over fifteen millions of souls, great and energetic as:it is, and disproportionate as is the slaveholding population to that of the free States. With this mighty power in your hands, with proof at every vote taken in this Capitol of your ability to continue it, can you of this interest entertain apprehensions for your safety 1 What more do you claim? What more can you have 1 How can those who- hold power be oppressed? by those who have none How can those who hold the power of thisGovernment fear it? I cannot believe there is occasion in the mind of any one belonging to this inter- est for ajdissolution of the Union, unless he be ambitious, unprincipled, and without hope of advancement. It will be reasonable enough to meet danger from other quarters ,hen it threatens mischief. But, Mr. President, I must iot omit somal'ther proofs of the toweririg magnitude of the slave interest here. It claims to itself and- its exer- tion whatever of merit there is in the overthrow of the pol- icy of internal/improvements, antfiof having broken down and rendered unpophulat the policy of so assessing and col- lecting the public revenue as to protect and encourage free labor. Over this fast great interest it claims a signal tri- umph for having defeated it. I need .pt multiply proofs of the zeal, activity, and sin- - gular success of..those who manage this interest. The in-. tegrity of the I~lion is probably quite as important to the slave territory-~ to the free. I cannot, therefore, credit the suggestion ,hat the people of the South-are so blinded to their interestrai to court so calamitous a result. What then is it that shakes this greatrepublic so that it reels upon- its foundations ? So thatwe are brought to a solemn pause here in thr public business, and are gravely and solemnly devising remedies to redeem us from threatened luin ? Sir, we have a set of resolutions,,nearly concocted, that are to *, So forth with healing power to calm thepubic mind, to al- lay the outbreakings of fanaticism, and to tranquillize the raging elements. The opinion of the majority of the Sen- ateisito work out this extraordinary result. But I again dsk, what it is tiat we are contending with ? What that threat- ons calamity, and ia thus easily to be subdued ? It is the abolitionists who come here in no very alarming numbers, Though the course pursued here has increased the aggre- gate, not to threaten the Government or to menace the Union tno, sir, not at all, but humbly to entreat and pray you to abolish slavery in the District of Columbia, where, I believe, there are about foity thousand people of all co- lors. Sir, they have claimed nothing but the right to beg and pray of the Senate to use its power for this purpose ' What more humble and less objectionable right can be claimed by man than the right of respectfully entreating? Yet, sir, the exercise of this poor privilege, by persons mostlyy females too;1ias brought us into grave deliberation, to rescue the Union from impending dissolution. Sir, I Cannot participating these fears, nor persuade myself that such causes will pri(uce such results, or that the Union Swill he attacked unless the, proivcation is given here. These abolitionists are. in, the free States. It has often i been aiti, and, was a da, or two past reiterated by the Se- kato,r. front MKissouri (Mr. BFNTro ) that theirbooks, papers; prints, &c. cannot enter the slave country, and therefore would do no harm t ere, even-if-the slaves could read, as- they never can reach them. It seemed also to be admitted *by the Senator from .Virginia (Mr. Rives) thatthere is no treated more temperately. There would probably be no ex-' citement among the slaveholders if it was not roused here; and there would be less here, if the flame kindled elsew here by the breath of these halls did not impart its warmth to this body. But, sir, I return, to the- inquiry, what is to be hoped from these resolutions Where are their healing proper- ties, their power to assuage resentments, and to allay irri- tated passions ? Are we now agitating the matter to any useful purpose? I read them, and while a part of them seemed to me to contain certain doctrines on slavery accord- ing with the sentiments of the mover, the residue seemed to be a mere avowal of a political creed. Not being quite cer- tain that I was right in the matter, I was minforted when myfriend from Delaware (Mr. BAYARD) rose and expressed the same sentiment. They professed to treat of abolition, but the worthy Senator declared that, on lifting the veil, he had discovered nullification concealed under the first of the series. He pointed the little fellow out to us hidden snugly under a thin covering of State right gauze. Now,: sir, I ask the Senate to look at that resolution. It is in these words: "Resolved, That in the adoption f the Federal C1on~tiutioin, the States adopting the same acted, severally, as free, indepen- dent, and sovereign States; and that each, for itself, by its own voluntary assent, entered the Union with the view to its increas- ed security against all dangersyldomestic as well as.foreigri, and the more perfect and secure enjoyment of its advantages, natu- lal, political, and social." And to inquire whether it has any apparent connexion with the abolition of slavery. The mover has already been ask- ed what he means by this resolution? How itis pertinent or applicable to the matter in hand What was his an- swer ? Did he say it was'to allay excitement, to suppress debate, or to-check petitions ? No, nothing of this-but he did, in substance, affirm that it was introduced is a sort of constitutional platform, upon which, as a newly'disco- vered footing, the Senate were to gather together and stand at this momentous crisis. The Constitution itself, without Senatorial amendments, is broad enough and good enough for me to stand upon. Sir, there have been many plat- forms, creeds, and confessions of faith, allof which are de- signed to tier down freedom of thought' and action, and which in general I do not believe have subserved any va- luable purposes. They are designed to carry out particu- lar doctrines, and so the Senator from Carolina avers in regard to his. He says it embraces the doctrine of '98, and it is expedient occasionally to reiterate fundamental principles. Magna Charta was reaffirmed, and hence the propriety, even upon this occasion, to reiterate and reaffirm the fundamentals of the doctrine of '98. What, sir, is the doctrine of '98? The Senator has had some bitter experience in this matter. He knows where it led him; he knows what results he has contended for under its authority, and he knows that many others, now on this floor, who claim to respect with equal deference the doctrines of'98, travelled pathswidely divergent from his; paths so opposed that they led to sharp, bitter, and alarm- ing conflict. This ought to teach the Senator not only the folly, but the danger of putting forth abstract theories upon the Constitution. But the Senator advances this theory because it contains the only conservative principle-the only remedy for the slave States. And what is that conservative principle, and what the remedy ? The Senator from Delaware, in giv- ing definition of the meaning of the resolution, solved, per- haps without designing it, this principle and remedy. The mover's view of State rights is, as I understood them, that the United States are confederated corporations; each a party to the Constitution in the nature of a treaty or con- federation; and when this Government, or perhaps one of the States, in the judgment of a State, sflall violate this compact, it may declare the whole contract void, because it has been broken, and cease to observe it with the same freedom and upon the same principles that one nation de- clares a treaty null because' the other party, in its opinion, has violated it. This must be the remedy-the right to se- cede from the Union when a State sees cause; and what is this but nullification? The resolution is capable of two constructions: one to bear out the Senator's view; the other the view of those who hold to a different construc- tion of the Constitution, and still call themselves State rights politicians. But what advantage can there be in avowing an opinion that can only excite controversy about its meaning. It is futile to attempt to make the Constitu- tion broader or n rrower, for we have no power to add or diminish. We may sanction puzzling theories about the probable intention of the United States, but the Constitu- tion must and will speak for itself, be the opinions-of this 'Senate what they may. The Public will look upon aich jets as they are-u nnecessar,and obligatory upon nobody, as mere attempts to give direction to the public judgment. Sir, I ask the Senator and the Senate to read the pre- amble td the Constitution, which I now bring to their at- tention : < We, the People of the United States, in order to form a more perfect union, establish justice, ensure domestic "tranquil- lity, .provide for the common defence, promote the general wel- fare, and secure the blessings of liberty to ourselves and our pos- terity, do rdain and establish this Constitution for the Ur.ited States of bn erica." And compare'it with this first resolution; observe its unequivocal language, "we; the People," &c. instead of the States, as corporations, and see how they will stand together. But, sir, I will not dwell on this matter, which has been again and again argued by the best talent in-the country. I care not whether the Constitution was made by the States, as corporations, or otherwise; it makes no provision for nullification ; gives no countenanceto it, but leaves it to stand on such theories as human invention has brought to its aid. I am' in no respect disposed to revive it, since it has met with signal public condemnation, and therefore shall vote against all abstractions where its seed is sown. It is no part of my duty to sit here forming creeds and confessions of faith for the purpose of experimenting upon public opinion. The People, I hope, will think and act for themselves, and will be too wise to entangle their understandings in the meshes of politicians. What is the second resolution ? It seems designed to point out the duties of the States towards one another in regard to their domestic institutions, and the duty of this Government to protect each State in the enjoyment of all such domestic institutions, and to restrain such States as assail those of other States. This country stretches through a wide space of the earth-embraces twenty-six States-some almost under a vertical sun, while others are in the region of frost. These domestic institutions, we all know, must be various, and different under differ- ent circumstances. Those, for example, suited to Loui- siana, will be ill fitted for Vermont. The views of differ- ent States, upon the necessity, character, and expediency of domestic institutions will always conflict, and our or- ganization was designed for that very purpose. -.The right of speech, the freedom of the press, the liberty of discus- sion, are domestic institutions; and are we to be restrained in the exercise of any of these precious rights, because others differ from us in opinion, and may hold our reason- ing against their institutions injurious'? These matters all belong to the States: and it lies with them to regulate them at pleasure, and without reference 'to the views or opinions of other States. If the designs to clothe this Government with power to abridge the privileges of the SttLtes, then the Senate can exercise no such authority, anil had better pause before it acts. But, sir, I must bring my remarks to a close, as the state of my health Will not permit me to proceed. I in- tended to haveexamined the character of these resolutions more in detail, and to state more fully my objections; but I must forbear. I cannot, however, sit down, without asking the Senator from South Carolina again-why he incorporates political doctrines with this matter-why he mingles with slavery the annexation of Texas to the UTrited Statea ? He says we must go back to elementary principles, to fundamentals. Cio back from where, and what are we t, go to? Sir, both you and the Senatgr participated, bilt with quite different sentiments, in that act of this Gc;vernment sometimes called the Force bill; and each of yciu had your opinions apon that-celebrated paper called th e Proclamation. -You were then arrayed against each ot her. The Senator is about to go back, and asks the Senate to go with him; and they do go with him, but where from and where to? He.cannot be going to the Force bill, or tfi te Proclamation; and doubtless he consi- ders the Senate as going from them, back to what ? 1 have endeavored, Ito s ow the character of the first resolu- tion, and the co; instruction which maybe put upon it. It may possibly be considered an attempt to renew a creed which the Force bill and the Proclamation had rendered of doubtful auth, ority. For myself, I had little sympathy with those who so much lauded the Preclamation, or sc much condemned the bill. The quarrel was between parts I. L-. n- _!- __. T -__ _- I.__ L -- -_ Mr. CALHOUN rose and said, that before he should notice such observations of the Senator from Massachusetts (Mr. DAIs) as he deemed pertinent to the question before the Senate, he felt:it a duty which he ow-' ed to himself, to state distinctly the position which he had heretofore held in relation to the subject of these resolu- tions. It is pot true, as the Senator supposes, that my views in relation to the proper course to be taken have pre- vailed,- It is just the reverse. Mr. C. said he had, he be- lieved, been in a standing minority from the time the sub- ject of abolition was first agitated in this body, till the in- troduction of these resolutions; and, although he had steadily objected to the reception of any abolition petitions, so far from taking a lead in laying them on the tabre, as- the Senator stated, he had not, in a single instance, made sudh a motion. He was, on the contrary, wholly opposed to the course. He had never doubted the folly of the po- sition, that we were bound to receive petitions, but might- lay them immediately on the table, without consideration or discussion. In the original debate, he told the Senator from Pennsylvania, (Mr. BUCHANAN,) who took a lead in favor of that course, that it was utterly indefensible, and that the reasons he (Mr. B.) assigned to prove that we were bound to receive, would be equally cogent to show that we were bound to refer, report on, discuss, and decide on them. He also told him what would be the conse- quences of his false position, all ofwhich have already been realized. The Senator from Kentucky has already taken the precise ground which he foretold would be taken. Nor is the Senator less mistaken in supposing that he has been opposed to the discussion of the subject. He has, it is true,- been utterly and unalterably opposed to any discussion with the abolitionists. They have no right to come here, and he was and is for shutting the door in their face; but he never shunned discussion when the subject came fairly up, nor would he, so long as the Senator's constituents, and others, continue to agitate the subject; in proof of which, he referred the Senator to the course he adopted in relation to the President's Message, some years since, on the circulation of incendiary publications through the mail. So far from avoiding discussion, he raised-a special committee on-that portion of the Message, made a full re- port adverse to the President's views, accompanied by a bill, which gave rise to much discussion. So, now, acting on the same principle, he had presented these resolutions as the antagonist of the Vermont resolutions. He touched on these misapprehensions of the Senator as to his course, the more fully, as there appeared to be a fixed determina- tion of late, both in and out of this Chamber, to mistake his course on this as well as other occasions.. : But this is not the only instance of the misstatement of his course by the Senator. He has misapprehended it as much in relation to the subject immediately under dis- cussion. Assuming, erroneously, as he had shown, that his position had been that Congress has no right to agi- tate or discuss this subject, however presented, he accu- ses him (Mr. C.) of challenging debate on the present oc- casion, and says that he (Mr. D.) would have remained silent had it not been for his challenge. The Senator greatly mistakes in supposing he had made any such chal- lenge, and he thought it would puzzle him to state when and in what terms it was given. It is true, he stated that the political creed of the Senator, and those who thought with him, in reference to the origin and structure of our Government, so far from affording any constitutional pro- tection against the assaults of the abolitionists, had roused their fanatical spirit into action, and he had, at the same time, called on the party generally who entertaifeil it, to show, if he was in a mistake as to the effect'of their creed, what protection it afforded. If the Senator has construed this into a challenge to discuss these resolutions, he must say he has most signally failed to meet it. He-has wholly shunned the point on which it was given. He hos note even attempted to show that the view. which he and his party take of the Constitution cn afford the least protec- tion against the dangers which now so seriously menafe the country and its institutions. His silence he had a right to consider as conclusive proof of the truth of his as- sertion, and the Senator ought not to be surprised if, after this tacit confession, he should turn to those who enter- tained the opposite constitutional views, and call on them exclusively to rally to the rescue at this hour of danger. The Senator was so conscious odfhis weakness on this point, that instead of attempting to point out a remedy, when his political theory afforded none, he took the oppo- site course, to deny that there was any danger to be re- pelled. He told us, gravely, that the abolitionists were no disunionists; that they had no ambitious.objects; no cor- rupt purpose; that they repudiated all interference with the-States; that they only aimed to abolish slavery in the Territories and in this District, where there were not more than 2,000 slaves; and that they claimed no right, but to beg you to grant them the innocent and harmless boon they craved, (of cutting our throats and burning our houses,) and that these beggars were but a handful, of whom a large portion were females. Such is the picture which he gives of this small band of innocents, and the harmless motives that actuate them; and this, in the face-of the constant, uniform, and open avowal, that their object is the total abolition of slavery in the States, as well as in this District and the Territories, and that they consider the abolition in the latter but as the first step to abolition in the former. But lie had received a letter that very morning from one of the fraternity, of high standing and authority, which gave a very different account of this small corps of humble beggars. He says that they count 1,500 societies, ave-. raging 100 individuals each, and are growing at the rate of one society a day. Here, then, we have 150,000 per- sons regularly organized, with a copious revenue, and 'an extensive and powerful press, (a large portion of whom are the Senator's constituents.) who. are waging regular war on the institutions of the Southern and Western States-- institutions that involve not less than$9.00,000,000 of pro-
perty, and.the prosperity and safety of an entire section of
this Union, in violation of the most solemnly plighted faith,
and subversion of the fundamental principles of the Con-
stitution; and yet the Senator can see neither harm nor
danger in all this. When we see one of his enlightened
understanding, and usually correct sentiments, thus think-
ing and feeling, what m stbe the tone of those with whom
he is daily associated, which could so blind his understand-
ing and blunt his moral perception ?
He next tells us that the abolitionists can do no harm;
that their publications cannot circulate in the slaveholding
States, and can do no mischief in the non-slaveholding
States; that the'evil exists here, where too much excite-
ment exists, and that if we would keep perfectly cool and
patient, and hear ourselves and constituents called robbers
and murderers, and our rights and property and lives at-
tacked, without moving hand or tongue, all would be well.
Accustomed, as he has been, to respect the Senator for his
sober and correct judgment and feelings on most subjects,
he could not but be surprised at the language which he
has held on the present occasion. Is his judgment so per-
verted that he can see no danger to the Constitution and
the Union, for which je professes, and, he doubted not, sin-
cerely, to have so much regard, in' the thousands of publi-
cations and lectures which are daily issued and delivered,
holding up, in the blackest colors, the character and insti-
tutions of nearly one-half of the Union-exciting towards
them the deepest feelings of abhorrence, to be returned, on
their part, with a detestation not less deep ? Is the univer-
sal spread of this deep, mutual'abhorrence compatible
with the existence of the Union ? If not, is it not time to
arrest it, and, of course, to deliberate on the means of do-
ing it ? Are the Senator's reason and feelings so far warped
that he either cannot apprehend the plainest consequences,
or, apprehending, is indifferent to them ?
But we are next told, for the hundredth time, that these
are mere abstract propositions, and not demanded, by the
occasion; on which account, with various other reasons
that he assigns, he cannot vote for them.
It was, he would suppose, perfectly needless for the
Senator to assign any reason for voting against these reso-
Slutiohs, or any other measure having the same object in
view, after what he had told us of the abolitionists, and the
purity and harmlessness of their objects-; nor is it at all sur-
prising that he should think that there was no necessity
for their introduction. But those who regard the subject
Sin a different light, who see danger where the Senator sees
nothing to apprehend, and crime where he beholds inno-
Scence, will come to a very different conclusion. They will
think it high time that this body should.define its position;
should declare its opinion as to those unprovoked assaults
Sof one portion of the Union on the other, and take the
Stand it intends to maintain in resistance to them; and
that the opposite course, to remain silent, or tamper with
the disease, is neither becoming its dignity nor its duty.
As to what the Senator has thought proper to say about
the secret mischief lurking under these resolutions, about
The Senator asks, why mingle abolition with political
matters 1 Why with the Texas question ? He knew not
how to reconcile such questions with the respect which he
has entertained for the Senator's intelligence and fairness.
Does not the Senator know that we have received hun-
dreds of petitions, and that they continue daily to pour in
on us in one incessant stream, praying that Texas may
not be admitted, on the ground that it would extend the
limits of the slaveholding portion of the Union ? Does he
not know that a sovereign State of the Unioi has come
here with its resolutions objecting to the annexation on the
same ground ? Does he not know that the entire move-
ment on abolition, with the object proposed to be effected,
and the means by which it is to be done, involves political
and constitutional questions and considerations of the high-
est possible magnitude, vital to the peace and safety of all ?
Knowing all this, with what propriety could he ask me the
questions he did ? Does he wish to shitt the burden by mak-
ing those who repel, and not those who assail, responsible ?
'Does he wish,to transfer the odium from those who make
war on our rights and property, tous, who defend them, and
.this, too, in the face of the most notorious facts ?
As brief as has been his notice of the Senator's apology
for the abolitionists, (for such he must consider his speech,)-
it is much longer than he would have made it, had it not
been for the respect which he has had for his talents and
character. He cannot consider the course he has pursued
in his speech as indicative of his actual feelings and fair-
ness, and is compelled to regard it as indicative of the dis.-
tempered state of the public sentiment of those he represent-
ed. Thus viewed, it affords an important lesson to those
he represented. Throughout, not a censure of the aboli-
tionists is whispered. All is excuse, defence, apology.
It is we, not they, who are the agitators ; it is we, not they,
Who are the disturbers of the peace and quiet of the coun-
try ; it is we, not they, who are the assailants; it is we,
not they, who harbor ambitious and improper designs; and
finally, it is we, not they, who meditate disunion. It is no
crime to attack us, but a heinous offence in us to defend
ourselves.
Mr. BAYARD moved to strike out the words the
several States," and insert the words of the Consti-
tut 0on itself, viz. the People of the United States." His
only object was to avoid a committal to a political creed, to
which he could not consent. If Mr. C. would admit this
slight change, Mr. B. would go with him.
Mr. CALHOUN objected, that those words were am-
biguous; they might be taken in a geographical sense,
meaning the inhabitants of the northern continent of Ame-
rica; or they might mean the People, as a People; or they
might mean the People only of the several separate States:
The latter was the only sense he could admit.
Mr. BAYARD urged that the very words of the Con-
stitution, to which every Senator had sworn, could not .
surely be objected to. It appeared to him that Mr. C. was
contending rather to put his own peculiar interpretation
upon that instrument, rather than following the instrument
itself, leaving the interpretation open. This he (Mr. B.)
contended ought to be done. Why, he asked, should Mr.
CALHOUN refuse to take the very words of the Constitution
-itself? .
Mr. CLAY, of Kentucky, said, if the Senator from Del-
aware would frame his amendment according to the histo-
rical fact, in the adoption of the Constitution, Mr. CLAY
would vote for it. The historical fact was, that the Con-
stitution was adopted by the People of the several States,
acting within their respective limits.
SMr. CALHOUN. The Senator, to establish the views
of the other side, has selected a passage for his amendment
which is their whole reliance. We rely on the historical
fact; a-nd the Senator from Delaware ought not to force
his interpretation on us.
Mr. BAYARD. The Senator is much mistaken if he
thinks our views are sustained only bythe preamble (of the
Constitution.) The historical fact is, that it is the Gov-
ernment, in the words of the Constitution, of the People
of the United States." -It is so decided ay Chief Justice
Marshall. When the preamble of the Constitution was
e, the People of New Hampshire, Vermont," &c., the
names of the several States were stricken out, and theex-
isting expression inserted, in order to avoid all ambiguity.
I do not depend at all on the preamble, but on the discus-
sion in the Convention. Ican demonstrate that it was re-
gardled as a Government emanating from the People as a
general body; and on this subject I shall be ready to wield
a laIce with the Senator on any suitable occasion. If the
Senator puts a different construction on those words, be it
so ; do not want to express any particular opinion on that
subjet.. ,
so Mr, w an o expr y p p
SMr. B ~ nD's amendment was lost, Yeas 8, Nays 34;
The remarks made by Mr. LUMPKIN, of Geor-
gia, on a previous day, having been imperfectly
heard and defectively reported in our paper, the
following, more correct report is now given, in
justice to Mr. L.:
Mr. LUMPKIN said it was with extreme reluctance
that he approached the subject under consideration. That
reluctance did not arise from a disposition to shrink from
the discharge of the duties which devolved on him. But
the delicacy and difficulty which were attached to this sub-
ject arose from the fact thatit was not a legitimate subject for
discussion in the Senate. By the constitutional compact of
the Union, this subject, if discussed at all, must be left to
the People and the States where slavery exists.
In regard to the resolutions offered by the gentleman
from South Carolina, (Mr. CALHOUN,) I consider it my du-
ty to remark (said Mr. L) that I have carefully and con-
siderately examined them, and am prepared to record my
vote in their favor, as originally submitted. Indeed, sir, I
can but regret that we could not have a direct vote upon
the resolutions in their original form, as I consider all the
amendments which have been suggested tending to muti-
late and disfigure, and lessen whatever of utility the pro-
posed resolutions embraced.
From the remarks which have fallen from the gentleman
from Delaware, (Mr. BAYARD,) in which he considers the
doctrine of nullification, in some obscure form, embraced in
these resolutions, I feel myself called upon, at this stage of
the discussion, to state that my friend (if I may so call him)
from South Carolina and myself stood as antipodes in the
days of excitement upon this doctrine in the South. I was
no nullifier, sir, but opposed it with all my might and
strength. I am still disposed to :cling to the Union with
that emphatic sentiment in my hear and on my lips, The
Federal Union must be preserved." But, sir, I am greatly
deceived if there will be any division amongst my consti-
tuents in regard to the resolutions now before the Senate.
-I believe that ninety-nine out of every hundred of the Peo-
ple of the South will approve of the principles laid down
in these resolutions. Upon this subject, sir, the South is
united as the voice of one man. We have to contend with
a common enemy. And, whatever may be our party names,
we are all State rights men. We go for a strict construc-
tion of the Constitution of the United States. We con-
cede nothing to the Federal Government by implication.
We respect the powers of the Federal Government in its
whole constitutional range; but that range is restricted
and limited to its specified powers of war, peace, treaties:
levying and collecting taxes, regulating commerce, and the
corresponding Legislative, Executive, and-Judicial powers,
This sir, is'the great outline, in brief, of the Federal Con-
stitution; and, sir, this Constitution was brought into exis-
tence by a spirit of amity, and that mutual deference and
concession which the peculiarity of our situation as a people
at that time demanded. If each State had then contend-
ed for, and rigidly adhered to, its own peculiar habits and
local prejudices and prepossessions, as the basis of a Go-
vernment for all the rest, this Federal 'Union of States
would never have been brought into existence. Butn nc
such surrender of opinion or power was required of the
States. The reserved rights of the States secured to each
the free and sovereign right to manage its own domestic
affairs in its own way, rightfully liable to no molestation
or interruption from the rest. The resolutions of the gen-
tleman from South Carolina (Mr. CALHOUN) having beer
brought to the consideration of the Senate, I should b(
L highly gratified at seeing them receive the sanction of this
honorable body; not that I believe they would put an effec.
Stual check to these deluded people called fanatics, but ii
Might serve as a rallying point for the sane. If the wis-
dom of our friends, and the friends of the Union, in the
non-slaveholding States, cannot devise the ways and mrearn
to stay the fury of these infuriated abolitionists, we of the
slaveholding States can only rely upon our own powel
within our own bounds. Whenever we find any of these
disturbers of the peace within our jurisdiction, we must ex-
t ecute our laws-punish them-and punish them in the
Most exemplary manner. They are our inveterate ene
tended upon this occasion, and sincerely hope that the fur-
ther discussion of this subject may not.again make it my
duty to trespass further upon the time of the Senate.
FROM THE CHARLESTON COURIER.
OCEOLA AT THE CHARLESTON THEATRE.
BY JAMES B. RANSOM.
The chandeliers sent forth a dazzling light,
And spltndid lamps and paintings shone around,
The scenery was superb, and all looked bright,
While not one vacant seat could there be found.
Indeed, a prince of high pretensions might
Have viewed the scene without a single frown-
For beauty, fashion, learning, all combined
To form a crowd, genteel, polite, refined.
Then OCEOLA, with his warriors came-
A stern, unbending stoic band they were-
Whose names, in truth, will long be known to fame,"
For deeds of valor, and for love of war.
With car-fings, trinkets, necklaces, and bands,
Heads deck'd with feathers, rings upon their hands-
A group so mild, grotesque, and yet so sage,
Have very seldom looked upon the stage.
I mark'd the heavy thought upon his brow,
Which clung like mist around the mountain top,
And watched his listless mien and careless bow, 9
As tho' he saw the play, but heard it not.
And then his lips would breathe some secret vow,
To strike for injuries ne'er to be forgot,
And peril all, tho' life should be the cost,
To save his native home and country, lost.
The lovely glow of JULIANA'S* face,
Her smiles and blushes, and the tears she shed,
Her splendid attitude, and native grace,
Were, to his war-lit fancy, stale and dead.
Yes, there he sat, subdued, butstill enraged,
(Like the fierce tiger when he's caught and caged,
Will lie composed-yet, when you pass him by,
You'll see a lurking devil in his eye."
The softest strains of music fell unheard,
And every sound seemed lost upon his ear-
While songs that spoke of love in every word,
Nor made him sigh, nor smile, nor drop a tear:
For his wild thoughts, like some unfettered bird,
Flew swift as lightning to that home too dear,
Where his undaunted heart still Longed to go,
To raise the savage yell, and fight the foe.
CHARLESTON, JAN. 7, 1838.
*The play was The Honey Moon-Juliana by Miss COOPER.
"W1 TANTED.-A trustworthy person as a Nurse for two
infants. A woman of experience in the business, and
especially one who has herself had children, would be pre-
ferred. A suitable person may obtain a corimfortable home
and liberal wages. Inquire at Gen. W. SMITH's, Georgetown.
jan 17
SADDLE HORSE FOR SALE.-Will be sold at
auction on Thursday morning, the 18th instant, between 9
and half past 9 o'clock, in front of Lloyd's Hotel, unless pre-
viously disposed of, a small handsome bay riding Horse, Saddle,
&c. This Horse will be eight years old next Spring; paces
easily, though not fast; trots tolerably well, and canters uncom-
monly well, and is remarkably sprightly. Until the sale, he
may be seen and examined at Pumphrey's Stable, back of
Brown's. E. DYER,
jan 17-2t Auctioneer.
] WEW METALLIC PENS.-W. FISCHLERhas just
received Waring, Commercial, Damascus, and Eagle
Steel Pens, of excellent quality. Also, in store, eVery variety.
of Perry's, Gillott's, Windle's, and Heeley & Son's genuine
Steel Pens, wholesale and retail, at Stationers' Hall.
P LANK IOOKS.-All kinds of Blank Books kept
constantly on hand, for sale at the lowest prices, at
GARRET ANDERSON'S
Cheap Book, Stationery, and Fancy Store, Penn. Avenue,
jan 17-3t between llth and 12th ste.
LACKWOOl1'S MAGAZINE.-Subscribers to the
above work are repeclfully.requested to call in person at
Station ers' Hall, and obtain the November number just received.
B jan 17 (Adv. & Met.) W. FISCHER.
T EXAS.-Just published dnd for sale at Stationers' Hall,
Texas, or an answer to the objections urged against her
admission into the Union. Price only 12N cts.
jan 17 (Adv. & Met.) W. FISCHER.
20 0 SLAV'tS WANTED.-The subscriber will
0 ~give higher prices, in cash, for hkely youngslaves,
of both sexes, than any other person in this market, or who
may come. I can be find at the large yellow house on 7th
street, or at Alexander Lee's Lottery and Exchange Office. All
communications will be promptly attended to.
N. B. I will pay at all times liberal commissions for informa-
tion. THOMAS N. DAVIS.
jan 17-eo3m
B LANK BOOKS.-The subscriber has lately received
from the North a lot of half bound Cap Blank Books,
which will he sold at the low price of twenty cents per quire.
Also, Demy, Long Cap, Record Legers, 4to Blank Books at
unusually low prices. R. FARNHAM,
Between Ninth and Tenth streets,
jan 17 Pennsylvania avenue.
"1ARSH'S BOOK-KEEPING.-The science of
double-entry book-keeping simplified in the introduc-
tion of an infallible rule for Dr. and Cr. calculated to insure a
complete knowledge of the theory and practice of accounts, by
C. C. Marsh, accountant, improved edition.
Also, Bennett's American system of practical book-keeping.
For sale,-between 9th and 10th streets, Varnum's Row,
Penn. avenue, R. FARNHAM.
jan 17
]J FOR RENT-The three-story brick Dwelling and
trM Store on 7th st,, opposite the Patriotic Bank of Wasfi-
I ington, next door to Mr. John A. Donohoo. Possession
given immediately. The dwelling, if desired, can be rented
separate from the store. For terms apply toiMessrs. Kneller &
Co., a few doors below the premises, or to the subscriber.
jan 17-3t THOMAS FERRAL.
1 0 REAMS of superior Envelope Paper, large size, are
1! for sale a'tStationers' Hall.
RECOMMENDED BY THE FACULTY.-
Howard's Compound Sirup of Carrageen, a safe, simple,
pleasant, and effectual remedy for chronic coughs, asthmas,
consumption, &c.
This sirup has deservedly acquired great reputation, and
the confidence of physicians, as a remedy in the cure of pul-
monary diseases. It is not offered as a specific, but will be
found generally effectual in the cure of chronic coughs, asth-
mas, &c. and will frequently relieve obstinate pulmonary dis-
eases.
s- When circumstancesadmit, it should be used under the
direction of a physician.
Prepared and sold, wholesale and retail, at my Pharmacy,
near 7 Buildings. FLODOARDO HOWARD.
Also for sale by S. J. Todd, C. Stott, G. S. Farquhar, and
C. Boyle, Washington; G. M. Sofitheron, Georgetown.; Win.
- Stabler and John Sears, Alexandria.
jan 8-2awlmoif (Nat Amer & Pot Adv)
DR. BIGELOW has taken apartments at Mrs. Bihler's,
between 9th and 10th streets, Pennsylvania avenue.
The most perfect operations for the health and preservation of
the Teeth executed in the neatest mainer. Superior artificial
and natural Teeth supplied. He has letters and recommenda-
tions from gentlemen of the highest respectability.
N. B. Persons afflicted with diseases of the Eye or Ear
are most respectfully invited to call. jan 15--if3t
REAL ESTATE LOTTERY,
EMACK'S OFFICE.
THE following valuable prizes, amounting to $80,310, con- sisting of valuable Mills, Farms, Houses, Lots, and Per- sonal Property of various kinds, &c. situated in Washington county, Maryland, within two miles of Gagerstown, and six miles of Williamsport, will positively be d~mwn on the 1st of February, 1838. Who will not risk$10 to obtain a valuable Mill, ($33,333,) or another valued at$16,000, or another valued at $6,600, he'- sides Farm', Houses, Lots, &c. and thereby obtain a home for life, for so small a sum ? SPLENDID SCHEME. SHAFER'S REAL 1 Prize, valued at 1 Do do 1 Do do 1 Do do I Do do 2 Do of - 1 Do of 1 Do of 6 Do of, 1 Do of 3 Do of 1 o Do of E STATE LOTTERY.$33,333
16,000
6,600
2,600
1,067
667 each.
600-
400
S 300 each.
336
267
SS 250
IEY WEST.
Letter to a Gentleman in Washington, dated
KEY WEST, DEC. 30, 1837.
DEAR SIR: In my last, I gave you a short description of
Key West, and touched upon its advantages as a naval
rendezvous for the protection or annoyance of the most
flourishing commerce in the. world. In this, I propose to
pursue the subjects of your inquiry.
From its latitude and growth, this island may be pro-
nounced decidedly tropical. Mercury rarely rises above
88 degrees in the hottest day of summer, and has never
but once fallen as low as 45 degrees in winter. The clie
mate is, therefore, mild, and not subject to the same chan-
ges as at places farther north; When. the island was oc-
cupied by Commodore Porter, in 1823, as a naval station,
it was found very sickly, as was alleged by him, principally
on account of the exposed service of the seamen in open
boats, and for the want of the common comforts of life.
Since then, sickness appeared in 1825 and in 1829. But
the buildings are now more comfortable and commodious,
rain-water cisterns are numerous, and the woods are cut
away to give a better circulation of air; and I doubt if a
place can be found enjoying more perfect health than Key
West has during the last seven or eight years. It is but
fair'to predict that every improvement in and around the
town will increase the comforts of the citizens, and render
their exemption from prevailing sickness surer.
But with the finest climate in the world, with extraordi-
nary advantages in natural position, and acknowledged
health, there is yet a great drawback upon the comfort of
the inhabitants in the summer. I mean the insects called
musquitoes. From June to September, after the sun sinks
below the horizon, there is need for all the patience and
philosophy that each can muster to his support.
Perhaps niopart of the world will hold out so great in-
ducements to invalids laboring under consumptive Affec-
tions as this island, so soon as good accommodations Are
provided. A commodious Hotel, I understand, is to be
erected this winter, and several buildings of the better
class are riow in progress, and the day is not far distant
when the feeble and the sick may enjoy all the comforts
their condition requires. ...
The inhabitants are generally orderly and peaceable.
There are several, both male and female,,who would be
deemed excellent society in any community.. Since 1832,
families are constantly locating themselves on the Key,
and the presence of accomplished females tends to give a
higher tone to the morals of any community. It is be-
lieved that there is not only more intelligence among the
inhabitants than at any former period, but also far more una -
nimity and charitable feeling. Perhaps 1 ought to add,
that the ordinances of religion, with regular worship on
the Sabbath, have greatly aided other causes of ameliora-
tion. An Episcopal church is organized, and a clergyman
of great learning and piety is supported here, aided by the
Missionary Society.
As to the business and future prospects of Key West, I
am less able to approach accuracy. The wrecking busi-
ness doubtless stands first on the list, though but few per-.
sons residing on this Key are directly interested therein.
The principal part of the wreckers and owners belong to
Indian Key, and the northern ports. But the wrecking
business transacted here indirectly gives occupation to ma-
ny. The next business is the fisheries-and particularly
taking live fish to Havana market. There are about
twenty Northern smacks employed in this business. And
the returns for the-capital and labot expended are sure and
liberal. The fisheries on the main land for salting and
drying fish for the same market, have been abandoned--
since the Seminole war broke out. These will doubtless
be resumed with success on the return of peace.
Salt Making, which has jot commenced, promises to
be the best investment and pursuit in this island. I say
promises, for the experiment, though successful, is yet in
its infancy. A company has been incorporated, and erect.
ed one string of covered works (about 2,500 salt-work
feet) in connexion with a natural' salt-pond of three hun-
dred and forty acres, at the northeasterly end of the island.
In the works the New Bedford and Bahama plans of salt
making are united, and the result last year was very flat-
tering. The 2,50Q feet making 4,500 bushels of salt, of
an excellent quality, in nine months, which is about six
times the New Bedford yield. These' works are yet in-
complete as respects the ground reservoirs in the pond.
The proprietors believe these can be so improved as to in-
crease the annual yield from one-fourth to one-third per'
foot. Another string of works are just finished', d esti-
mates are made out for two more, on an improved scale,
which, when complete, it is believed, will make the whole
stock yield 20 per cent. per annum; and when 20 or 30
strings are completed, the result must be from 40 to 50 per
cent. per annum. I have carefully examined the salt pond
and its neighborhood. and believe there can be assigned no
definite limit to the salt that may be manufactured here.
This half-way ground, between the North and the South,
is most favorably located to effect sales and the shipment
of salt, inasmuch as vessels in ballast almost always stop
here, looking for freight. As soon as these works are suf-
ficiently extended to inisure cargoes of salt, vessels will
seek it for a cargo when freights are dull, and it can, with
equal facility, be sent on the Gulf or Atlantic coasts.
Other salt ponds, it is said, exist along this chain of islands,
which, at some future day, will make them the Bahamas
(as far as salt making is concerned,) of the United States.
The Lafayette Salt Company is yet in its infancy, and lit-
tle or no aid has, thus far, been drawn from the NIorth. ,
From the results already attained, and the character and
standing of the men at the head of the company, there can
be no doubt of the ultimate and sure value of the stock to
Northern capitalists. The books are now open for further
subscriptions, and it is to be hoped success will crown the
endeasvrs of this company to extend their works to the li-
mit of their i. trter.
As to the future business prospects of this island, I am,
perhaps, less able to give an opinion that should be relied
on. The business incident to wrecking, fishing, and salt
making, I should suppose, would increase as commerce in-
creases, and the salt works are extended, and give a gra-
dual increase to the growth of the place. In case of a war
with a commercial nation, and Key West is not left ex-
posed to capture, it will be a convenient mart for the disp6-
sition of-prizes, and will suddenly increase. In the event,
also, of commercial restrictions; requiring an indirect trade
with any port of the West Indies, Key West will become
a depot for merchandise, and become a busy mart. It is
now increasing in buildings, and when the Seminoles, if
ever, are removed from the peninsula, the fisheries and ag-
of this place. On the whole, for the reasons above stated,
I consider Key West as a place of much higher importance,
every way, than my own or the general impression had
heretofore assigned to it. Yours, &c. .
W RS RONCKENDORFF has tivo comfortable
COhambers unoccupied, and wvil be pleased to'aecom-
modate a gentleman and lady, or two gentlemen, with Board.
jan 17
THE GOROSTIZA PAMPHLET--For sale by
F. TAYLOR, in pamphlet form, An Examination and
Review of a painphlet printed and secretly circulated by M.
E. Gorostiza, previous to his departure from the United Etates,
and by him entitled Correspondence between the Mexican
Legation and the Department of State of the United States re-
specting the Passage of the Sabine." jan 17
LI FOR RENT-A large two-story brick HOUSF,
situated on Maryland Avenue, in a healthy and desire k -.
l able neighborhood, with a large lot adjoining, and ev-
ery convenience attached, such as stable, carriage-house, &c.
Possession can be given immediately. To a good and permanent
tenant the terms will be moderate. Application to be made to
Mr. Wm. Lloyd, living near the premises, dr. to the subscriber.
jan 17-eo3t JOHN PICKRELL.
A PPAIIACHICOLALAND COMPANY.-Sales
at auction.-the Trustees arid Directors of the above
Company hereby give notice that a public sale of lots, in the'
City of Appalachicola, will take place there on the second
Wednesday, being the fourteenth day of March next, under
the direction of Joseph Delafield, Esq. the Agekt of the Com-
pany.
SThe Agent is also-authorized to sell at private sale that part
of the Company's land lying on both sides of the Railroad, be-
tweeh Tallahassee and St. Mark's: and also the land lying-on
the Ocklockonyland Little rivers, in such quantities as may be
agreed upon. Also, any other tracts.which nmay be wanted.
A company of Surveyors are now employed in laying out said
tracts preparatory to a sale..
The terms of the public sale will be one-fourth cash, or ap-
proved drafts at 60 days on one of the Northern cities. Th*
balance in three equal annual payments with interest; and
when ,nid navments are completed, a clear title will be given.
*' <
TWENTY-FIFTH CONGRESS.
TUESDAY, JANUARY 16, 1838.
IN SENATE.
A message was received from the Presidentpof the United
States through Mr. A. VAN BUREN, his private Secretary.
The following petitions and memorials weie presented
and referred:
By Mr. McKEAN: The memorial of J. N. Barker and
others, of Philadelphia, remonstrating against repealing the
law establishing an express mail. Referred to the Com-
mittee on the Post Office ard Post Roads.
Also, two petitions from citizens of Philadelphia,,pray-
ing Congress to adopt measures, for finishing the frigate
Raritan. Referred to the Committee on Naval Affairsm
Also, a memorial from young men of Philadelphiai re-
monstrating against annexing Texas to the United States.
Laid on the table.
By Mr. RUGGLES : The memorial of Jos. H. Adams,
President of the Ocean Insurance Company, and of a nunm-
ber of other officers of Marine Insurance Companies,
and of a number ofthe merchants of Boston, for the erec-
tion at the entrance of Boston harbor of'orie of Morse's
Perpetual Fog Bells. The memorial commends the inven-
tion as an important one'to the commercial community, for
the invention of which, Mr. Morse has received a gold
medal from the Mechanics'Association of Boston, and the
highest reward in the power of the New York Mechanics'
Institute to bestow.
Mr. R. also presented the petition of several shipmasters
and branch pilots of Boston, for the same-object.
By Mr. MERRICK: For indemnity for Spanish spo-
liations. y .
By Mr. TALLMADGE: From importing hardware
merchants 6f New York, praying the repeal of certain
clauses in-the second section of the tariff act of 1832.
Laidin the table, as a bill ~br that object is already in pro-
gress.
SBy Mr. YOUNG: For the establishment of a post
route.
By Mr. RIVES: A remonstrance against the reinstate-
ment of officers in the Navy who have withdrawn or been
dismissed.
And by Messrs. FULTON, MERRICK, ROANE,
PIERCE, SMITH, of Indiana, and MORRIS, all on
individual claims. ,
VERMONT RESOLUTIONS.
Mr. SWIFT again presented the resolutions of the Le-
gislature of Vermont, in relation to slavery and the slave
trade in the District of Columbia and Territories, and
against the annexation of Texas to the Union. Mr. S.
accompanied the presentation of theresolutions with some
reniarks, and moved that they be received.
A discussion arose on the subject, in which Messrs.
PRENTISS, PRESTOS, STRANGE, KING, CAL-
HOUN, SWIFT, WHITE, and ROANE participated.
Mr. STRANGE moved to lay the motion to receive the
resolutions on the table; which was negatived-Ayes 12,
Snoes-26.. :
On motiori of Mr. SWIFT, the resolutions were then
received, and laid on the table for the present.
SUB-TREASURY. SCHEME.
Mr. WRIGHT, from the Committee on Finance, re-
ported a bill, imposing additional duties on certain public
officers as depositaries, creating receivers general of the
public money, and to regulate the deposits of the public
money. .
Mr. WRIGHT,moved that it be made the special order
for this day week.
Mr. CLAY, ofKy., said hi would like a little longer
time. The Senate had been in session a great while, and
public expectation was high on this subject. Mr. C. had
never seen a section f the bill; he understood that its de-
tails were numerous and he therefore hoped that more
time would be given for the consideration of a bill of so
momentous a character.
Mri WEBSTER rose, he said, to make two questions.
In regard to this, and other measures of the Government,
he had no disposition to oppose delay, with any purpose of
thwarting them. This, however, was one of the most im-
portant subjects before the Senate, and of great interest to
the community; he, therefore, desired as much delay as
was consistent with a due regard to the convenience of
the Senate. He also wished that the bill and all its pro-
visions should be made as generally known as possible.
He therefore moved that the bill be made the special order
Sfor this day tfo weeks, and that 1,500 extra copies be or-
dered to be printed.
Mr. CALHOUN expressed a wish that the postpone-
ment might be only to this day week, and not a fortnight,
as proposed by Mr. WEBSTER. He thought a speedy ac-
tion on this important measure highly desirable. It did
not require any more discussion, as it was fully discussed
last session, and the country was well acquainted with its
merits.
The question being taken on Mr. ,VVEBSTER'S motion,
the bill was made the special order for this day two weeks:
Ayes 22, noes 20; and 1,500 extra copies were ordered to be
printed.
Mr. PRESTON, on leave, introduced a bill for the re-
lief of Dr. Thomas Cooper. Read twice, and referred.
Mr. SEVIER offered a resolution calling upon the Sec-
retary of War to examine the papers of the Cherokee
Prince Leocheehau, and to give his opinion as to the lia-
bility of the United States for depredations committed upon
his property.
Mri. BUCHANAN said, that having seen this morning
in the National Intelligencer that the statement of Col.
in the militia on the frontiers, so as to render the preserva-
tion of peace yet more difficult than it was before, he was
anxious to take' up the bill to prevent conterminous colli-
sions, and-to give authority for the seizure of arms intend-
ed to be used against neighboring Powers.
The Senate refused to take it up at this hour, (it being
late,) and
HOUSE OF REPRESENTATIVES.
MISSISSIPPI ELECTION.
The CHAIR having announced that this was the day
on which, by a resolution of the House, the report of the
Committee on Elections on the claim of two new members
from Mississippi to a seat in the House was to be taken up
for consideration-
Mr. BRONSON offered the following resolution:
"Resolved, That Messrs. S. S. PRENTISS and T. J. WOaD
are not members of the 25th Congress, and are not entitled to
seats in this House as such."
Before any decision,on this resolution-
Mr. WISE, by leave, moved, as preliminary, a resolu-
tion, which, on suggestion of ,Mr. BELL, he modified so as
Resolved, That S. S. PRENTISS and T. J. WORD have
leave to occupy a seat within the bar of this House pending the
discussion of the report of the Committee on Elections upon
their petition ; and that they have leave to speak to the merits
of the petition and the report of the committee thereon."
Mr. HOWARD here presented a statement in manu-
script (there having been no time to print,) by Mr. CLAI-
BORNE, who is detained by illness from the House, pre-
senting an argument of the case in behalf of himself and
his colleague, and moved that itbe read at the Clerk's table.
After some conversation on points of order, Mr. WISE,
at the suggestion of Mr. BELL, modified his resolution so
as to preserve the words of a similar resolution adopted in
the case of Mr. Arnold.
Mr. FOSTER moved to amend the resolution as fol-
lows:
Resolved, That S. S. Prentissand T. J. Word have leave to
appear at the bar of this House, and argue the merits of their
application forseats therein."
This'amendment was debated by Messrs. FOSTER,
WISE, BELL, POPE, GLASCOCK, HAMER,
REED, CUSHING, HAWES, and BIDDLE; when,
to end this preliminary discussion, Mr. BOON moved the
Previous Question.
The motion was sustained by the House, the previous
question put and carried, and the main question on the
adoption of the original resolution was decided in the af-
firmative.
By order of the CHAIR, seats were now assigned in
the broad passage in front of the Chair for Messrs. PREN-
TISS and WORD.
fr. T- Tx A i T -_ .
for the printing of this paper
tion, though he thought the printing'would be very proper.
Mr. GHOLSON then said that he and. his colleague
were not before this House.asking its charity for the
printing of this paper: and though they might not be as
able as some to pay printers' bills, they did not beg the
House to pay for it. Mr. G. added another remark, which
led to a reply from M-r.-WISE, of a very angry character,
which was, instantly retorted by Mr. GHOLSON, in a
similar strain.
The CHAIR interposed, in both cases, the moment the
words were uttered.
JIThe reading of the paper was now ordered; and the
Mr. RENC-HER moved that, in consequence of the ill-
ness of Mr. CLAIBORNE, the further consideration of the
case be postponed.
The paper having been read through-
Mr. BELL offered a resolution makl'ng this report the
order of the day for this lay and every day succeeding,
until the subject should have been finally disposed of.
Mr. RENCHER said that Messrs. PRENTISS and WORD
concurred in the wish that the case should be postponed if-
lthere was a prospect that Mr. CLAIBORNE would be able,'
Mr. GHOLSON said it was his own desire, and that of
his'colleague, that there should be no delay, but that Mr.
BEuL'S motion should prevail.
Mr. BELL modified the resolution so as not to make
this subject the order of the day till one o'clock each day,
in which form it was agreed to.
The question now recurring on the resolution moved at
the commencement of the sitting by Mr. BRONSON, viz.
"Resolved4, That S. S. PiENTISS -and T. J. WORD are not
members of tlie 25th Congress, and are not entitled to
seats in this Hbuse as such."
Mr. UNDEIWVOOD moved for the printing'of Mr.
motion a desultory debate arose, in which Messrs. UNDER-
WOOD, GRAVES, HOWARD, PATTON, JENIFER, and CILLEY
took part; when, to save time, Mr. UNDERWOOD Withdrew
his motion.
The motion was immediately renewed by Mr. CILLEY,
and the discussion renewed'by Messrs. CILLEY, PENNrY-
BACKER, GRAVES, BRONSON, GLASCOCK, PATTONi and
UNDERWOOD, when, the question being put, the printing
was ordered.
Mr. DAWSON, of Georgia, after some allusion to the
very painful occurrence between Messrs. GHOLSON and
WISE, moved the following resolution: -
"The hon. SAMI. J. GHOLSON, a member of this House
from the State of Misissippi, and the hon. H. A. W\ISE, also a
member from the State of Virginia, having spoken language
subject to the sensure of this House, because in violation of its
rules,
Be it therefore Resolved, That those gentlemen do now
make submission to this body."
As this motion had relation to a question of privilege,.
the CHAIR decided that"it took precedence of every subject'
before the House.'
Statements were then made by Mr. WISE and Mr.
GHOLSON, (in the course of which both were called to
order by the CHAIR;) after which,
Mr. GLASCOCK moved to lay the resolution of Mr.
DAWSON on the table. He withdrew the motion, however,
at the request of
Mr. MERCER, who quoted .Jeffers'bn's Manual to,
prove that the motion of Mr. DAWSON, hot having been
made immediately after the occurrence, was out of order.
He then, in compliance with a promise to Mr. GLASCOCK,
renewed the motion to lay the resolution on)te table ; and
it was laid on the table.
Mr. MERCER then offered the following resolution:
Resolved, That Messrs. GHOLSON and WISE, members of
this House, between whom warm words have passed in debate,
be required by the Speaker to declare in their places that they
will not prosecute further the quarrel which has arisen this day
between them."
This resolution was supported at great length, and with
great feeling and earnestness, by Mr. MERCER.
Mr. JENIFER, believing that it would aggravate, in-
stead of allaying, the excitement, moved to lay the resolu-
tion on the table.
'On this motion, Mr. MERCER demanded the yeas and
nays, which, being taken, resulted as follows: Yeas 78,
nays 123.
So the House refused to lay the resohition on the table.
The debate was further continued by Messrs. HOW-
ARD, POPE, JENIFER, MERCER, TURNEY,
GLASCOCK, CUSHING, and REED, when the House,
without-coming to any decision, on motion of Mr. JENI-
In the House of Representatives, on Monday, Mr. Ew-
ING presented the following petitions, viz.
Of M. Bruillet, for compensation of a horse lost in the public
service.
Of Wm. Purcell, for compensation of two horses lost in the
public service.
And the claim of D. S. Chambers, for deficiency of land pa-
tented.
must take the freedom of remonstrating, in behalf of my-
self and others, against a sore grievance. During the pre-
sent session of Congress you have adopted the practice of
giving in detail all the petitions presented to the two
Houses, not only on private claims, pensions, &c. (which
interest nobody but the petitioners, and the notice of which
might well be dispensed with until reported on,) but also of
the swarms of petitions about slavery and Texas; and, if
they go on increasing, they will soon take up your whole
paper, to the exclusion of every thing else. You have
adopted the practice, I suppose, either to gratity the mem-
bers presenting these petitions, or to entertain and instruct
beg you t6 believe that you are egregiously mistaken-unless,
might tolerate them as those other necessary evils-tax
lists, &c.-because they would then have at least the con-
solution of knowing that if they are annoyed you are ben-
efited.
Look, gentlemen, for instance, at this morning's Intelli-
gencer. Out of the near six columns of Congressional
inatter which you gave us, three of them are taken up with
an enumeration and description of individual petitions pre-
sented on the subject above referred to. In the name of
mercy, gentlemen, if these endless petitions must be no-
ticed, would it not be sufficient for all the purposes of pub-
lic information to state that Mr. A B presented so many
petitions from so many inhabitants of such a State, without
giving them all and each in detail as at present? Think of
this, I pray you, and see if the evil be not susceptible of a
W4SHINGTON, JAN. 16.
[Here is a correspondent who objects, on general grounds,
to a practice of recent growth, which, we supposed, con-
cerned only ourselves, byhe expense it involves, and our
advertising customers by the space in our columns of which
it deprives them of the use of. We do not (as our corres-
pondent appears inclined to) consider the publication of the
list of petitions an evil in itself, but, on the contrary, as
desirable, if made at the cost of those whom it benefits,
that is, of the Public generally, and not of the proprietors
of newspapers, to whom, without any advantage, it is in
fact a dead loss. But until very lately, these lists were not
published, and are now published only partially; that is,
so far as those who present these petitions communicate the
names, contents, &c. to the Reporters. We shall not, for
a time at least, refuse a place to these petition lists; but,
as well to avoid taxing too heavily the good-will of publish-
ers, as to make the publication general, authentic, and reg-
ula., it is really highly desirable that the House of Repre-
sentatives (or perhaps both Houses) should cause these
things to be published daily, or periodically, in some one
or more papers published at the Seat of Government, pay-
ing therefore a reasonable compensation, such as is paid for
ordinary advertising. Such a regulation would at least he
an approach to a compliance with the positive injunction,
which is now effectively a DEAD letter, in the Constitution,
that "each House shall keep a journal of its proceedings,
and from time to time ubhLi.h hthA. amem."--l nrrna 1
WASHINGTON.
"Liberty and Union, now and forever, one aiid
inseparable."
WEDNESDAY, JANUARY i7, 1838.
In the Senate, yesterday,.a bill was report d
by the Committee -on Finance, embracing the
project of the Administration, varying conside,-
rably from the sub-Treasury scheme of the late
extra session, and by so much the more excep-.
tionable as it varies from that scheme. The
bill is of great length, and we have no means
of obtaining a: copy of it. The following is,
however, a summary of its principal provisions:
First. Certain rooms in the new Treasury
Building, with safes and vaults, are to consti-
tute the Treasury of the United States,
Second. The Mint and the Branch Mints are
also to be public depositories of the public mo-"
neys.
Tird. Certain special depositories are to be
create,, viiz, in Charleston, New York, and
Boston, r and officers to be appointed therefore, ta.
be called Receivers-General, with salaries, &1c.
Fourth. In certain cases, collectors of public
moneys may make special deposits in banks
the,'key upon such depositories to be retained
by the depositing officer.
Fifth. Many .provisions are proposed, by
bond and otherwise, for the security of money
in the hands of those,officers.
Sixth.' Exclusive specie payments, for all dues:
and ebts to Government, to be required after a
certain time: say, four or six years hence.
SAnothier feature, if we understand aright, an-
nals the-equisition of specie payments at the
land offices, permitting the alternative of paying
the money into the Treasury at Washingtdon,
certificates of such payment to be received as
cash at the land offices.
THE BANK FAILURE AT BosToN.-The fail-
ure of the Commonwealth's Bank, it appears,
has been anticipated by well-informed persons4
in the cify of Boston for several months past.-
The following remarkable paragraphs, referring
to that institution, are extracted from the file of
the Boston Atlas:
FROM THE ATLAS OF JUNE 5, 1837.
Is it not true that one of the deposit banks in this city.
-4the bank of the new-fashioned "Democracy"(!)-the
,Pet par excellence of the Administration-would have
been compelled to sop payment on the day of the general
suspension, even if the bank? in New York and this city
had continued to pay.? Was it not brought up short,
the day before-unable to pay its balances-and with %
few pieces of foreign gold, and less than a hundred dollars
in silver, roi. the sum total of specie in its vaults 1
FROM .THE ATLAS OF JUNE 2, 1837.
No sooner did they receive the deposits, than the pet
,banks commenced a career of the most blind, reckless, and
profligate speculations, that ever disgraced any age or na-
tion. And who took the lead in themin Pet-Bank di-
rectors, officers, and stockholders-custom-house officers,
And where did the money come from ? What paid'-foar
Eastern lands-Western lands-the piles of granite on
our wharves-to insinuate nothing qf the monument of
Spoils Patriotism in the vicinity of Dorchester Heights ?
BILLS OF THE PET BANKS. And to whom were these
loaned ? To the- Whig merchant ? NOT AT ALL. To
the noisy partisan and the hopeful convert. The Pet
Banks had a double duty of payment and proselytism;
they were to reward the fidelity of old friends, to enlight-
en, encourage, and .stimulate the new-born zeal of the
converted.
NEW WORK ON EDUCATION.
HOGAN & THOMPSON (of Philadelphia) have in press,
and will publish in a few days, a work with the following ti-
tle: Hints on a System of Popular Education.; addressed
to'R. S. Field, Esq. Chairman of the Committee on Edu-
cation in the Legislature of New Jersey, and to the Rev. A.
B. Dod, Professor of Mathematics in the College of New
Jersey, by E. C. WINES, author of Two Years and a
Half in the Navy," and late Principal of the Edgehill
School. 12mo.
We have had an opportunity of examining some of the
sheets of this work in its progress through the press, and
have been struck with the very able and clear manner in
which the importance of popular education is illustrated
and enforced. We cannot .but think the work will meet
warm approbation, and be productive of immense good, by
drawing the attention of the Public to this very important
subject, and urging it with the force of conviction upon
their minds.--Conm. Herald.
CINCINNATI, JAN. 9.
ANOTHER SUB-TREASURY BANK RUN OFF.-We lear;
that a Mr. Klinepeeler, or some similar name, postmaster
at Liberty, Montgomery county, in this State, after peeling
the bark off most of the Van-Jacks of the township, had
decamped with the spoils, some eight or ten thousand dol-
lars, which he had borrowed from his political friends ;
most of the amount without security, such was their con-
fidence in the integrity of Mr. Van Buren's new Treasury
Banks.
CORRESPONDENCE OF THE BALTIMORE CHRONICLE.
ANNAPOLIS, (MD.) JAN. 10, 1838.
Applications for divorces are pouring in from all quar-
ters. You would suppose, from the anxiety of so many to
be relieved from the marriage vow, that'" the place ofhap-
piness is the single station." There are some curious
cases before the House. One from the Eastern Shore sets
forth that the parties quarrelled the day after the wed-
ding," and now hate each other with a brotherly hate;"
what this last is you will find on reference to Byron's Let-
ters; he said he loved a '.' good hater," and methinks he
would have been enraptured with the swain in this case.
'Tis melancholy, and fearful sign
Of human frailty, folly, also crime,
That love and marriage rarely can combine.
Within a few years divorces have been granted, with
but little objection, for almost any cause, and the indiffer-
ence with which they pass is indeed a fearful sign" of
the absence in the majority of the members of the proper
feeling as to the sanctity of the marriage rite.
I believe no one part of the State is distinguished above
another for the number of its applications for divorces, un-
less it be the city of Baltimore. One divorce, if no more,
has already been granted to persons residing in that city,
and there is a score of others pending.
An attempt, somewhat original, at extorting money, has
been ineffectually played off upon Gov. EVERETT, of Mas-
sachusetts. A letter was addressed to him, stating that
certain parties had it in contemplation to abduct one of his
children, and keep it secluded till he should sign a pardon
for a convict now in the State Prison. The writer said
for ten dollars, to be sent to him through the post office, he
would disclose to the Governor the names of all the parties.
The Governor very properly sent the letter to the District,
Attorney, who caused a letter addressed as requestedsto be
put into the post office, instructing the postmaster to detain
whoever should eall for it. A man named Hollis Parker
did call, was arrested, confessed that he wrote the letter,
andi ini;ta ,i thft it i fn nnm..... ... ....... .-_ :_
We comply with the request of a distinguish-
ed citizen by copying the following article, ard
inviting to it the serious attention of all whom it
in any wise concerns :
F ROM THE UNITED STATES GAZETTE.
To the Public, and to the Managers, Agents, and
.Thei fiolowing appeal is made in the hope that it may be
the means of saving life, or at least of securing exemption
from cruel injury to some fellow-cieatures.
...The desire to render this appeal as forcible as possible
must be the apology for the gloomy details which accom-
pany it. It.is not to gratify the usual morbid propensity'to
rnad of distress, or to give food to so depraved an appetite,
but, if possible, to produce such an effect upon all concern-
ed, as may be the.means of obviating the evil, which was
the source of all the agony of those hours that immediately
followed the late accident on the PORTSMOUTH AND ROAN-
OKE RAILROAD, and of the cruel sufferings by which it has
been attended.
The writer of this appeal and his only daughter were
part of the company who took their places in the centre car
of three, which formed a part of the train.upon the above-
named-road, on the morning of the 10th of De'ember. Our
fellow-passengers were two ladies, their children, onein-
fant, two female servants, and several gentlemen; the other
cars contained an unknown number, but the third car was
occupied principally by a party of females, who entered it
upon the route, and who Were the greatest sufferers by the
accident which occurred shortly afterward. They were in
high spirits, and were evidently seeking pleasure in their
trip, looking forth with gay countenances and cheerful an-
ticipations of enjoyment, at the very moment that they
were brought to the most excruciating tortures, some of
them to death.
The cars were moving at the rate of 12 or 14 miles an
hour, when a crash was heard, and the writer was con-
scious of a sensation of rising in the air, then fall,1but fur-
ther than this all sensatinti and memory fail, save the agony
of that moment, when his child was before him, fellow-
creatures, including females and children, around, with the
instant conviction that death, in fearful torture, was claim-
ing his victims from among them.
STothe scene which followed no pen can give description.
The three cars had been crushed to pieces, and all whom
they contained, except those only of the second car, were
lying, torn and mangled, on and among the fragments.
The cries, lamentations, and prayers of the less injured,,
distressing as they were, were far less appalling than the
faltered accents of the mother who said, '.Tell my son to
come tome, Iam dyin." She died that nimgt; CQuldany
thing be more agonizing than the situation 6f that poor
girl, who lay with her limbs jammed and crushed by the
iron wheels for hours, whilst all our efforts to relieve her,
in the absence of all means, and far removed from all aid,
were in vain. Let us close this detail by stating that two
burden cars were emptied of their loads, and in them were
placed twelve of those whose cruel injuries and heart-
.rending lamentation's can never be forgotten, and they'
were conveyed back to the nearest station. The remainder,
with the uninjured, were taken on bhy another engine and
.train, which arrived in a few hours at the place of the ac-
cident.
The loss of life, the wounds and sufferings of the maim-
ed, were not necessaryconsequences of the accident to the
Engine, but were occasioned by the excessively reprehen-
siblefustom of.attaching burden cars behind the passen-
ger cars. In-this instance the facts and circumstances are
as follows': -'
The road is constructed of light plate rails, laid on wood-
en string pieces and 'sleepers. The end of one of the rails
was loose, and'stood up; it struck the scraper, and threw
the engine off the track and into the side of the ditch, when
its further progress was arrested, the front of the. frame
being buried in the earth. The tender was throw ron its
side, against the back part of the engine, which lay partly
over the track; against this opposing mass, the light pas-
senger cars were crushed to pieces; and the foot of the
baggage car was s:ove in, as it lay upon the pile of ruins,
by the momentum of a number of burden cars loaded
with cotton, in bales, which formed the rear of the train.
It is consistent with the laws of matter and motion, and
many circumstances warrant the belief, that if the passen-
ger cars had been placed behind the burden cars, or if
there had been no burden cars in the train, little or no in-
jury would have resulted to the passengers from the acci-
dent.
A pair of horses which were in a car forming part of the
train were apparently entirely uninjured, and a carriage
standing upon an open car was scarcely displaced.
In continuance of his journey, with all these circum-
stances fresh upon his memory, and when the papers had
announced the deaths of two of the sufferers, the writer
entered one of the cars at Washington for Baltimore, and
was painfully compelled to witness the attachment of bur-
den cars behind the train, and this too in the night, when
obstructions upon the road are much more to be feared.
When the agent came round to examine, and collect tick-
ets, the writer made the circumstance a subject of earnest
remonstrance. The agent, with honest candor, acknow-
ledged that the custom was extremely reprehensible, cited
instances of injury from the like causes, regretted that' his
remonstrances had not been attended to, and said that.no-
thing was left to him but to look to his own safety in case
of accident.
In publishing this statement, the writer does not mean
to censure any one; he makes no charge of neglect or
carelessness; but he believes that the parties who had con-
trol were not sufficiently aware of the consequence of the
sudden arrestation, (and the consequent liability to injury
of every thing which intervenes,) of such a moving mass
as a train of burden cars, at the ordinary rate of railroad
progress. He feels that this statement is an indispensable
duty to his fellow-creatures, called for by circumstances
From which, providentially, he is a sufferer only in a slight
degree.
Sales This IDay.
SALE OF GENTEEL FURNITURE.-By E.
Dyer.-On Wednesday next, 17th inst. at 11 o'clock A.
M. I shall sell at the two-story brick house corner of2d street
and Pennsylvania Avenue, immediately east of the railroad
depot, the household furniture of the present occupant, consist-
ing, in part, of-
Mahogany Sideboard and Tables,
Good Ingrain Carpets, Parlor and Chamber Chairs,
Andirons, Shovels, Tongs, and Fenders,
Small Franklin Stove, Mahogany Bureaus,
Washstands, Basins and Ewers,
With many other articles necessary to housekeepers.
Also- Kitchen requisites.
In addition-1 Counter, 2 Show-cases, and Show-bottles.
EDWARD DYER,
jan "15--d3t Auctioneer.
SPLENDID GOLD JEWELRY, WAATCHES,
CLOTIIS, AND FANCY ARTICLES.-This
evening, and will be continued, if not all sold, on Tuesday and
Wednesday evenings next, at 7 o'clock, under a deed of trust,
for cash, a splendid assortment of Blue, Black, Brown, Oxford
Mixed, Green, and Drab Broadcloths, superfine Stripe, Drab,
and Mixed Cassimeres and Satinets, Gum Suspenders, Sewing
Silks, Worked Capes and Collars, Patent Thread, Sewing Cot-
ton, Spbol Cotton, French Perfumery, Dirks, Solid Gold Breast-
pins, Earrings, Finger-rings, Guard Chains and Keys, Specta-
cles, Eye-glasses, Gold and Silver Watches, Penknives and
Razors, with a general assortment of Fancy articles.
SETH H YATT, Auctioneer,
jan 15-MT&W Opposite Brown's Hotel.
Y A. McINTIRE.-BOOKS-BOOKS-Books.
On Wednesday evening, 17th instant, at 7 o'clock, I
shall sell at auction by catalogue, a large and valuable collec-
tion of miscellaneous Books, in plain, fancy, and handsome
bindings. To the lovers of literature in its various branches
a good opportunity offers.
SURVEYORSr COMPASSES.-A few cases of handsome
and superior Surveyors' Compasses remain unsold. These
are first-rate articles, and will be offered at private sale during
the present week. ALEX. McINTIRE,
jan 15-3t (Globe) Auctioneer.
BOOKS TO, BE IMPORTED FROM LON-
DON.-F. TAYLOR has made arrangements by
which he is enabled to import from London any books (English
or foreign) that are to be found there, upon as advantageous
terms as are possessed by any house in this country.
HOME INTELLIGENCE E.
[REPORTED FOR THE NATIONAL INTELLIGaNICER.]
At a meeting held at the First Presbyterian Church, on
4J street, on the evening of January 14, .1838, to adopt
measures to promote the Sanctiftcdtion qf the Sabbath, in
the city of WASHINGTON and its vicinity,the Rev. STEPHEN
CHAPIN, D. D. was called to the Chair, and J. L. EDWARDs
was appointed Secretary.
The meeting was opened with prayer by the Chairman,
which was followed by an appropriate hymn.
Rev. J. Q. SItTH, of Georgetown, after an appropriate',
address, offered the following resolution, which was second-
ed by the Rev. W. HAWLEY, and which passed unani-
mously,:: .
Resolved, That the-Sabbath was instituted by Almighty God
at the creation, and, as he has never abrogated it, it now remains
in full force.; '
Rev. Mr. MC.LAIN, after some pertinent remarks, offered the.
following resolution, which also was adopted :
Resolved, That the necessity for the Sabbath is fouBndin the'
feature of man and his relations to the Creator.
Rev. Mr. NOBLE, after a suitable address, offered the follow-
ing resolution, which passed :
Resolved, That the liberties and welfare of this nation are
identified with the strict observance of the Sabbath.
The following resolution, offered by the Rev. Mr. WEBSTER,
SResolved, That all abbor performed on the Sabbath, save in
answer to the calls of niercy, is a violation of the law of God.
On motion of Mr. PARKE, seconded by the Rev. Dr. LAUrIE,
the following resolution was adopted : f
Resolved, That the frequent violations of the Holy Sabbath
by professors of religion and others, are great and threatening
evils, and it behooves them- and all others to aid in arresting
their progress.. ,
Rev. Mr. HAWLEY offered the following resolution, which was
Resolved, That theMayor of the city of Washington be re-
spectfully requested to require some of the police officers ol' the
Corporation to perambulate our streets, and the different parts
of the city, on the Holy Sabbath, and suppress, by all lawful
means, the noisy and unlawful games in which the youth and
others of our city are so frequently and wickedly engaged in de-
secration of that sacred time, a'id which so powerfully tend to
,subvert the Christian Sabbath; and that the Rev. Dr. Laurie,
and the Rev. Messrs. Hawley,-Webster, and Parke be a coin-
Inittee to wait on the Mayor, and furnish him with a copy of this
resolution.
The Rev. J. C. SMITH offered the following resolution, which
Resolved, That, to promote more extensively the objects of
this meeting,'the ministers of all denominations officiating in the
respective churches in this District be requested'to preach on
the strict observance and sanctification of the Sabbath ON or
about the first Sabbath in February next, and thatthe Secretary
furnish each one of them a copy of this resolution.
Col. JAs. L. EDWARDS offered the following resolutipnwhich
Resolved, That Messrs. JACOB GIDEON, jr. J. W. HAND,
and JAcOB NOLLNER be a committee to publish the proceedings
of this meeting, and adopt and prosecute such measures as may
,best promote the sanctification of the Sabbath.
After the benediction,' by the Chairman, the meeting ad-
journed. .
STEPHEN CHAPIN, D.D. Chairman.
JAS. L. EDWARDS, Secretary.
NATIONAL Tai:ATRE.-The lovers of the drama in this
city have an opportunity of gratifying themselves by wit-
nessing the performances of a great tragedian who is
now playing, under a short-engagement, at the National
Theatre. 'Mr. BOOTH is announced to perform for four
.nights, and it will certainly be the fault of the patrons of
the legitimate drama in this city, if his stay is not pro-
longed for some time beyond that period. For the sake
of the drama's best interests, as well as for that of
the great tragedian himself and the manager, we hopi
that overflowing, brilliant, and-intelligent audiences will
attend the theatre during the whole of Booth's engage-
ment. It is deemed unnecessary to say a single word in
praise of BooTH. His professional merit is pre-eminent,
and has been acknowledged by a host of critics, both in
this country and in Europe. We would'-merely remark
that such is the high estimation in which Boolh's repre-
sentation of RICHARD, IAGO, MACBETH, SIR GILES OVER-
REACH, and other kindred characters, are held, that they
may be witnessed (,as they have 'been, -probably, in this
country and Europe) a hundred times, without any dimi-
nution .of interest on the part of those intellectual and
enlightened audiences who have uniformly and universally
attended his performances.
We understand from gentlemen of the first standing in
the country as dramatic critics, and who have recently
witnessed Mr. Booth's celebrated performances in Balti-
more, that at no former period of his professional career
did that great tragedian appear to greater advantage. And
we are further assured by the Baltimore press generally,
that Mr. Booth's late performances in that city drev the
most brilliant and crowded audiences that were ever wit-
nessed.
While we are writing on this subject, we conceive that
we should not be doing ample justice to the Manager,
whose conduct on a recent occasion, in ridding the house
of a grievous annoyance, has elicited the warm approba-
tion of every respectable patron of the theatre in this c6m-
munity, if we did not particularly recommend the estab-
lishment to the patronage of the friends of the regular and
well-conducted drama. Having attended the house during
the last week, we can testify that no occurrence, calcu-
lated in the smallest degree to offend the eye or ears of
female delicacy, or to disturb the audience, has ever taken
'place. The Public may be assured that, since the exclu-
sion of disorderly persons from the theatre, &c. the best
order has prevailed; and we hope that such a state of
things will continue without any detriment totthe mana-
ger's interest.
MARRIAGES.
On Sunday, the 7th inst. by the Rev. Mr. VAN HOR-
SEIGH, Mr. JAMES J. JARBOE to Miss ELIZABETH
.ELLEN SMOOT, all of the District of Columbia.
At the residence of W. HASELL HUNT, Esq. in Nash-
ville, (Tenn.) on the evening of Thursday, Dec. 28, by
the Rev. J. THOMAS WHEAT, Rector of Christ Churchi
Mr. ALEXANDER S,. VILLEPLAIT to Miss SA-
RAH A. ROSCOE.
On Thursday last, by the Rev. W. McLAIN, JAMES
CUNNINGHAM to Miss SARAH. ANN JONES, all
of this city.
DEATHS.
On Monday, the 15th instant, in the 28th year of her
age, BRIDGET WHELAN, relict of the late WILLIAM
WHELAN.
In Georgetown, D. C. on the morning of the 14th Janu-
ary, SOPHIA M. SMITH, youngest daughter of AN-
THONY SMITH, in the 17th year of her age, after a painful
illness of three weeks, which she bore with the greatest
composure and fortitude.
NATIONAL THEATRE.-WASHINGTON.
The highly celebrated Tragedian Mr. BOOTH will make his
second appearance in his favorite character of'Sir Edward Mo'-
timer.
THIS EVENING, JANUARY 17,
Will be performed Coleman's Drama of the'
IRON CHEST;
Or, The Mysterious Murderer.
Sir Edward Mortimer, Mr. BOOTH.
To conclude with the interesting Drama of
THERESE,
The Orphan of Geneva.
On Thursday the lastnight but one of the engagementof Mr.
BOOTH.
GEORGETOWN ASSEMBLIES-Will be held
at the Union Hotel on the evenings of the 25th of Janu-
ary, and the 8th and 22d of February.
Tickets of admission may be obtained by non-subscribers on
application to any manager.
MANAGEas.
Colonel John Cox J. S. Ringgold
Com. Charles Morris A. H. Dodge
Col. Samuel Humphreya Jno. T. Cochrane
Cul. John Carter T. R. Cruttenden
Col. Geo. C. Washington J. W. Bronaugh, Jr.
Dr. 0. M. Linthicum R.L., Mackall
John Mason, Jr. Geo. C. Bomford
Wm. A. Gordon Daniel Boyd
S NEW YOR, JAir. 15.
The latest news we have from Nivy Island id
the apparent intention of Gen. VANs RZNSSE-
LiER to leave the Islard.- and go upr'the Lake
in order to nibark on the main laud; of thi
apparent abandonment of all attack upmo itby
MCNABB, because he cannot make his militia
volunteer; of the. arrival of another steamboat
at Schlosser, the Aarcenola, from Buffalo, to at-,
as a ferryboat there and of the increase of the
Na'vy Island forces by French Canadians and
Americans.
Of DUNCOMBE'S reported forces in the vici-
nity of Fort, Maiden, if there are a.q all "i
doubtful. -One report puts'him on aBmish Is-
land, another says he has difd. i
The probability is, .as -McNABB cannot:. or -
dare not, make an attack upon Navy Island,
that the Navy Islanders-will .ail in a steamboat
-to go p p the:Lake, in ordet:'effect a debarica-
tion, for the purpose of joining compatriota,
who,4it is said, are somewhere or *other, I Iar
not for 'i certainty where.
The British account of the Schlosser affair
has made -a most painful iinpression upon th~i
public mind and embarrassed ve~r9 muc~91d'
peaceful action uof the Goveinment on the -
tir. Gen. SCOTT will not be able 't, do any
"thing effectual there. One fact shiews he tem-
per of the people he will have t0Sec. te his
orders,--when the steamboat frii Buffalo
reached Schlosser, the militia stationed there to
preserve neutrality gave three cheers, and the
band struck 'up Yankep Dbodle.
This is the day for transactions in foreign ex-
change. To-morrow being packet day, excihani
on London is 110 to 110 which isahigher than
bythe last packets. 'Our moriyed men here feel
a good deal of interest in MrfffJAUDON'S effotlt
in London to effect; thedsasof. the surplus U.
S. Bank stock, which, if effected, will save us
from a large drain of money, or rather give ui
so much credit there.
Our rates of domes ic exchange vary every
day on Mississippi, Detroit, and St. Louis, end
a quotation made one day will not- stand the L
next." ..
The Boston banks, io fai s I can judge, all
stand firm, the Cornmo eahth except, which
has gone over the dam for ti prisnt at-least.
From JAMAICA we hadyvda.tes to the 23d ult.
but there is nothing new'iorth,.qiting.
Our Legislatureswill 'suspend, if not -peal,
the small' ill law1 .. .
Treasury idri-d n6w-ill at the Board of Bro-
kers 1 percent ,under paper money, and Trea
sury notes bths per cent. under paper money,
which is R2 d-3 per centiunder Aerican gold.
U. S.Bank Stck is, p. tol0- Europosn
opzations, witf:the .,bd account given of iti
qo'dlitiopa,are the cause of this ri-qr, psrhAmpq
Our merchants here. express much surprise
tion party in Congress on the subject of the
currency. The contraction of the'currency which
must take place till Congress exercises its vested
power for its regulation is destruction to all trade'
and all enterprise. The spring is coning t he
season of improvements; and Congress :doing, ;
on this subject, nothing. If the _special depb-
site system is to be pursued, it is time to know it.
SPLENDID CAPITALS.
$30,000--.$10,000. '
14 DRAWN NUMBERS..
VIRGINIA STATE LOTTERY,
For the benefitof the Mechanical Benevolent Society of Nor-
folk.
Class No. 1, for 1838.
To be drawn at Alexandria, Va. on Saturday, Jan. 27, 1838..
GRAND SCHEME.
$30,000-$ 1 0,000- $6,000-- 5,000.$4,000-$3,000-$-2,500--$2,120-82,000. 25 prizes of 1,000 20 do 500 20 do 400, &e. Tickets$1 b-Halves $5-Quarters$2 50.
Certificates of packages of 25 whole tickets, 8120 -
Do do 25 half do 60
Do do 25 quarter do 30
$25,000 CAPITAL. MARYLAND STATE LOTTERY. Class No. 4, for 1838. To be drawn at Baltimore, Jan. 31, 1838. -CAPITAL PRIZES.$25,000-$8,000-$5,000-$3,500-$2,392
20 prizes of 2,000
20 do 500
20 do 4Q0
20 do 200, &.
Tickets $10-Halves$5 -Quarters $2 50. Certificates of packages of 22 whole tickets 8120 Do do 22half do 60 Do do 22 quarter do 3.0 VIRGINIA STATE LOTTERY, For the benefit of Monongalia Academy. Class No. I, for 1838. To be drawn at Alexandria, Va. on the 3d Feb. 1838. GRAND CAPITAL PRIZES.$35,294-$11,764-$6,000-$5,000-$3,000,
-23,500-$2,361. 50 of$1,000! &c. &c.
Tickets $10-Halves$5-Quarters $2 50. Certificates of packages of 25 whole tickets$13
Do do 25 half do- 65
Do ( do 25- quarter do 32 50
VIRGINIA STATE LOTTERY,
For the benefit of the town of Wheeling. .
Class No. 1, for 1838.
To be drawn at Alexandria, Virginia, Saturday, Feb. 10, 1838.
SPLENDID SCHEME.
$30,000-$10,000-$6,000-$5,000-$4,000,$2,500-$2,000-$1,747.
25 prizes of 1,000
25 do 500
28 do 300, &e.
Tickets $10-Halves,$5- Quarters $2 40*,, Certificates of packages of25 whole tickets,$130
Do. do 25 half do 65
Do. do 25 quarter do 82 0
STATE OF VIRGINIA,
Class No. 1, for 1838.
To be drawn at Alexandria, Va., on Saturday, Feb. 17, 1838.
'MOST SPLENDID PRIZES.
- $40,000 1 prize of BALTIMORE & PORT DEPOSIT RAIL-ROAD Of1lICE, BALTIMORE, DECEMBER 28. THE CARS OF THE PHILADELPHIA, SWILMINGTON.AND BALTI1OtDRI RAJL- ROAD COMPANIES, will, for the present, continue to leave the depot ir Pratt street daily at 7 o'clock A. M. for Phil- adelphia and the intermediate places. The Rail road from Wilmington towards Philadelphia being completed to the Schuylkill, the passengers will be conveyed Son that road to Philadelphia as soon as the Delaware becomes impracticable for the steamboat Telegraph, all the arrangements Having been made to that effect. dec 30 L OUISA RAILROAD.-The transportation of passen- gers on this road commenced regularly on the 22d inst. The charges are as follows: Frederick's Hall Depot to Beaverdam$00 75
S Ditto to Junction 1 50
Ditto to Richmond 2 75
,, Ditto to Fredericksburg 3 75
A daily train leaves Richmond for Frederick's Hall at 121
SP. PiFederick's Hall for'Richmond and Fredericksburg, at
4 A iM.
SStages will be run regularly between Frederick's Hall and
Charlottesville by Me isrs. Boyd & Edmonds.& Stockton & Co.
in connexion with the train. The stage.fare will not exceed
,-$2 75. PasSengers preferring so to do will have it in their power;to pay at Richmond and Fredericksburg through to Charlottesville. DtDistance from Richmond to Frederick's Hall about 46 miles. Distance from Frederick's Hall to Charlottesville about 44. This train connects regularly with the mail line to and from Fredericksburg and Washington City. Passengers leaving Richmond or Fredericksburg at half past 12 o'clock in the day, arrive at Charlottesville, (with but little night travelliig,) by 10-o'clock next morning; and, in return, leaving Charlottes- ville after the arrival of the stages from Staunton, arrive in SRichmond or Fredericksburg by half past 8 next morning. dec 25-ff ,WASHINGTON BRANCH RAILROAD.-On V and after Monday next, the 11th instant, the cars will leave the depot in this city for Baltimore at 9 o'clock A. M., in- stead of 9f A. M., as heretofore. The object of this alteialion is to render certain the arrival of the train at Baltimore early enough to afford ample time for pas- sengers going North to take the steamboat, which now departs daly'for' Philadelphia, at half past 12 o'clock. The afternoon train will, as heretofore, leave the depot at a S/ quarter after 5 o'clock P. M., sept 8-d6t&wtf WASHINGTON BRANCH RAILROAD TRANSPORTATION DEPOT, WASHINGTON, DEC. 13,1837. IT IS RESPECTFULLY MADE KNOWN, That merchandise or other commodities received at this Delpot for delivery in this city, or to be forwarded to Baltimore, or t' points on the line of 'the road, will, hereafter, be subject to the following regulations, of which those interested will please .take notice : 1st. The freight and charges on all goods consigned to indi- viduals in this city or its vicinity must be paid before their re- moval from the depot. S2d. Commodities offered for transportation must be distinctly marked, and be accompanied by a list, in duplicate, of the num- ber'and description of packages to be forwarded; the name of the consignee, and of the party forwarding the same; otherwise they cannot be received.. 'The Company wil not be responsible for damage arising from leakage or breakage; nor will they be responsible for damage alleged to have leen received by any goods or commodities transported by them, unless the claim shall be made before the Sfemoval of the goods from the depot; further, if goods which shall have been transported on this road be not received or Taken aiyay by their consignees or owners on the day of their Arrival at the depot, the Company will not be responsible for, or pay any claims for loss or damage which maybe sustained by such goods;.in other words, if goods as above described, be per- mitted'to rmairrineoron the cats on the railway, or at the de- pot one or more nights after their arrival, they will remain so at the exclusive risk of the owners or consignees. -? The hours for. receiving and delivering goods will, until fur- ther notice, be from 9 A. M. tiliA P. M. - .By order: I SAML.:STETTINIUS, dec 14- -Agent P ...-...f.r.ilt OTik.;-The stea- mer COLUMBIA, Captain JAM ES MITCHELL, will leave Washington Severe Thursday, at 12 o'clock A. M. drrling in Ndrfolk in due time for the Charleston steam- boat, Portsmouth railroad cars, and the Richmond steamboat. Returning, will leave Norfolkat 3 o'clock'P. M. every Sun- day. Passage and fare$6. (Globe & Alex.,Gaz.)
Oct 28-eotf
TELLING, TRAVELING, AND POCKET
( ISTOLS.-- R large and general assortment, of supe-
rior quality, London made, for sale on the most accommodating
terms,,at the old established Snuff, Tobacco and Fancy Store,
between llth and 1L2thi streets, Penn. Av.
;: ...... .... LEWIS JOHNSON.
P. S. Best 0o1t Yell'w 'leaf James River and Barboursville
,. Chewing Tobacco. Real Prinoipe and Havana Segars. All
kinds of best European aud American Snuffs, &c. <&c. for sale
cheap as above. a.n I
j'_EORGE SWEAN Y, Notary Public, Counvey-
a. U ancer, and General Agent, has opened an office in
" Elliot's new block of btfiliings, on Pennsylvania Avenue, east of
o him. .
G. S. will undertake the prosecution of claims upon Congress
and the Executive Departments of the Government, and will
be .thankful to those who may favor him with orders or com-
missions.
His well-known experience in all such business as he pro-
poses to undertake, remndrs particular references unnecessary.
dec 4--dlww3m '[Globe]
01 The Baltimore Patriot, Philadelphia Enquirer, New York
SJournal of Commerce, Charleston Courier, New Orleans Bul-
$letin, Cincinnati Gazette, Louisville Journal, and Mobile Com- mercial Advertiser will please to insert the above six times, and secf their accounts to the advertiser for payment. N EW WORtKS.-Letters of Lucius M. Piso, from Pal- 1 myra, tohis friend,,Marpus Curtius, at Rome. The Christian Professor, addressed, in a series of Counsels and Cautions, -to the members of Christian churches. By John Angell James. A New-Tribute to the Memory of J. Brainerd Taylor. Modern' Accomplishment%, or the March of IntelleCt.' By Miss C. Sinclair. Modern Society, or the M1arch of Intellect, the conclusion of Modei A omplishments. Byjiis C. Sinclair. Pretenisfo By Sarah Stickney, author of Poetry of Life. 2 vols. S Zinzendarff, and qther Poems., -By Mrs. L. Sigourney. ',' 'AGood Life,extracted from tli true plan of a Living Tfript, ..nan considered in his proper relation to th6 ordinary occu- itions and pursuits of life. With an introductory Essay. By John Brazer. The Christian Father at Home, or Manual of Parental In- stinction.' In two-parts: 1st. On the Neccssity of Salvation. 2. d. On the Way of Salvation. By W. C. Brownlee, DiD. SWorth a-Million. Stories from'Real Life. Part 5. The Young Wife, or Dutiesof Woman in the Marriage Re- lation. By Dr. Alcottj ', -Just received and- feo. sale, at No. 5,, yarnum's Row, be- tween 9th and 10th streets, Pennsylvania avenue. jani R. PARNHAM. FOSTER'S COUNTING HOUSE MANUAL; m" qor,the Merchani's, Banker's, and Tradcsnan's Assistant. SFor ale.bptween 9th and 10thstreets, Fennsylvjnia avenue. dee 8' R. FARNHAM. DB rLING'S PATENT" ROTARY PISTOLS. LEWIS JOHNSON has just received a case of iliese superior instruments, which he invites the Public to ca'l and see. .jan 5-3t .-1 ARYLAND POCKET ANNUAL lbr 1838, containing an almanac, eclipses, moveable feats, &c.' officers ofthe State, offiFers-oftheTseveral counties of the State, United States officers in Maryland, meetings of the courts, election returns, members of the Legislature, Executive of the United. States, Congress, dates of the Statq elections, revenue dof Maryland' State Government expenses, newspapers, &c. in Maryland, religions in the United States, popular statistics, heights of principal mountains; census: of the United States for S1830-estimated for 1840, population arranged, in sections, cen- sus of Maryland from 1790 to 1820 and '30, &o. The above w ork may be had at Stationers' Hall; price only 50 cents. jan 5 (Met & Adv) W. FISCHER. YCl OPREDIA OF HISTORY.--rA poplar Cy- elopedia of History, ancient and modnrn.-forminLr n a GREAT NORTH AND SOUTH EXPRESS LINE. Winter Arrangement. HALIFAX, WILMINGTON, AND CHARLESTON. While it avoids the dangers of the Capes, and the fatigues of 300 miles of staging, it offers to the traveller a route which, for speed, safety, comfort, and economy, is not equalled. GOING SOUTH. By this route, passengers who leave Baltimore on Monday and Friday, via the Chesapeake Bay Boats and Portsmouth Railroad, or via Washington city, the Fredericksburg, Rich- mond, and Petersburg Railroad, to Blakely, will reach Halifax on the evenings of the next days, viz. Tuesday and Saturday. From Halifax, they will be immediately conveyed, by post coaches and railroad, to Wilmington, where they will arrive on Thursday and Monday mornings, (having slept at South Wash- ington the preceding nights;) thence, after two hours' delay, to Charleston, in fromr12 to 16 hours; thence, by railroad, to Au- gusta. EXTRA.-Leave Baltimore or Washington city on Wednes- day, via Fredericksburg, Richmond, and Petersburg railroad to Blakely. Passengers will arrive at Halifax on Thursday even- ing, at Wilmington Saturday morning, and leave for Charleston on Monday. GOING NORTH. Leave Charleston every Sunday and Tuesday, at 5 o'clock P. M., reach' Wilmington the following mornings to breakfast. Leave Wilmington at 12 o'clock, and by railroad and post coaches arrive at Halifax on the evenings of the next days, viz. Tuesday and Thursday; sleep at Halifax, and the next morning proceed North, via the Petersburg, Richmond, and Fredericks- burg railroad. EXTRA.-Leave Wilmington on Friday, arrive at Halifax on Saturday, and the next morning, via the Portsmouth Railroad and Bay Boats, or the Petersburg, Richmond, and Fredericks- burg railroads. RECAPITULATION. GOING SourH. Leave Baltimore or Washington city Monday, Wednesday, and Friday, and arrive at Halifax Tuesday, Thursday, and Sa- turday. Arrive at Wilmington Thursday, Saturday, and Monday. Arrive at Charleston Friday, Tuesday, and Tuesday. GOING NORTH. Leave Charleston Sunday and Tuesday. Leave Wilmington Friday and Saturday. Arrive at Wilmington Monday, Wednesday, and Friday. Arrive at Halifax Tuesday, Thursday, and Saturday. The Portsmouth cars run daily ; the Petersburg cars on Sun- day, Monday, Wednesday, and Friday. Passengers will observe that, on this route, via the Chesa- peake Bay Boats and Portsmiouth Railroad, only one night's sleep is lost between New York and Augusta, or, via Peters- burg, only one-night between Richmond and Augusta. The coaches are now, the horses fresh and well trained, the drivers sober and skilful, the fare and accommodations good. The new, beautiful, and swift steamboat NORTH CAROLINA, built by Cor- nelius Vanderbilt, Esq., of New York, for the Company, has justbeen added to the line between Wilmington and Charles- ton. In fine, no expense has been Spared to render the line comfortable and safe. OFFICE W. & R. RAILROAD COMPANY, WILMINGTON, DECEMBER 14. jan 2-4w (Gl he) W INE STORE, Pennsylvania Avenue, third door West of 41 street, City of Washington. -M. L. GITTINGS, has on hand a superior Stock of old WINES and LIQUORS, consisting in part as follows: MADEIRAS. 20 dozen Reserved Madeira, very old and fine Burgundy Blackburn Murdoch Grape Juice Oliveira Tinta Sercial Otranto Malmsey Johnson Constantia do do do do do do Sdo do do do do do do do do do do do do do do do SHERRIES. 40 do Pale Lobo, Carera, Oldham, Gold, &c. very su- perior S40 do, -Brown, Lobo, Romano, Duff, Gordon's 20 do Pure Grape Juice, Port 20 do Otard, Dupuy & Co's Brandy, very superior S20 do do Pale do do 18 do Champagne Brandy do 15 do Peach do do 10 do Jamaica Spirits do 15 do Irish Whiskey do 20 do Monongahela Whiskey, 18 years old CHAMPAGNES. 50 do Sparkling Champagne, Napoleon brand 20 do do de Anchor do 15 do ; do do Grape do 10 do do do Harp do 69 do do do Pints, Napoleon do 20 do London Porter, Brown Stout, Scotch Ale, quart and pint bottles FRENCH WINES AND CORDIALS. - 50 dozen Clarets, Chateau Margeaux, Leoville, Medoc, St. Julien; Sauterne, White and Red Hermitage CORDIALS. 25 dozen Marisehino,Curacoa Liqueurs, Perfect Love,Cinna- mon, Rose, Lemon, Aniseed, &c. RHENISH WINES. 20 dozen Hock, Marcobruner, Hockheimer, &c. ON DRAFT. 12 pipes Madeira Reserved, Star, Burgundy, Murdoc, Black- burn, Howard March & Co.'s Tinta, Grape Juice, &c. very superior 4 butts Pale Sherry, Lobo, Carerp, Oldham, &c. 4 do Brown do do do do 2 do Pure Juice Port 1 do Irish Whiskey, very old and fine 6 barrels Monongahela Whiskey, 18 years old 3 pipes Otard, Dupuy & Co.'s Brandy, old and fine 1 do do Pale do do 1 do Charante Brandy do 1 do Champagne do do 2 do Holland Gin, Wesp, Anchor and Orange 2 do Jamaica Spirits 2 do St. Croix do 1 do Peach Brandy Demijohns loaned, and goods sent free of-porterage. dee 4-dtf C ASH FOR NEGROES.-I will give cash and liberal prices for a number of likely Negroes, under twenty-five years 'of age, families included. I can be found at B. O. She- kell's Tavern, a few doors below Lloyd's Tavern, opposite the Centre Market. JAMES H. BIRCH, june 26-tf Washington City. C harles County Court, August Term, 1837.-On the appearance of Zephaniah H. Turner, a petitioner for the benefit of the insolvent laws of this State, it is ordered by the court here that the bond of said Zephaniah H. Turner be respited until the 3d Monday in March next, and that he give noticejto his creditors that they be and appear before the Judges of Charles county court, on the third Monday in March next, to show cause, if any they have, why the said Zephaniah H. Tur- ner shall not have the benefit of said laws; provided a copy of -this order be published in some newspaper in the District of Columbia, once a week for two months successively previous to the said third Monday in March next. S Test, JOHN BARNES, dec 21-law2m Clerk. SUITARS.-Justopened, at Stationers' Hall, a large as- sortment of patent screw Guitars, of superior tone and finish, at prices from 10 to 45 dollars. Expected daily, three superior Piano Fortes, from the unri- valled- manufacturers Messrs. J. Chickering & Co. Boston, which wiil be sold at their prices. W. FISCHER. jan f0 (Adv.) S TATE OF MARYLAND, SeO.-On application to me the subscriber, a Judge of the Orphans' court of Charles -county, by petition, in writing, of Thomas H. Latimer, praying ft the benefit of the act of Assembly for the reliefof sundry insol- vent debtors, passed at November session, 1805, and the sever- al supplements thereto, a schedule of his property and a list of his creditors, on oath, as far as he can ascertain them, being annexed to his petition, and the said Thomas H. Latimer having satisfied me by competent testimony that he has residedin the State of Maryland two years immediately preceding the time of his application; it is therefore ordered by me that the said Thomas H. Latimer be discharged; and that he, by causing a copy of this order to be inserted in some newspaper published in the.District of Columbia once a week for two successive months before the third Monday of March ne.t, give notice to his creditors to appear before Charles County Court on the 3d Monday of March next, for the purpose of recommending a Trustee for their benefit, and show cause, if any they have, why the said Thomas H. Latimer should not have the benefit of said act and supplements thereto, as prayed. TALL AND WINTER GOODS.-C. Ecklofl, Merchant Tailor Pennsylvania avenue, respectfully calls the attention of his customers and the Public to his large and elegant assortment of FALL AND WINTER GOODS; which he will make up, to order, at the shortest notice, and in the best and most fashionable style. Together with a first-rate stock of fashionable READY MADE CLOTHING, FANCY ARTICLES, &c., which will make his assort- ment, in every respect, fall and complete. nov 13-eod2m AGENCY AT WASHING GTON.-J AMES H.CA US- STEN, (late of Baltimore,) having made this city his perma- nentresidence,and located his dwellingand office directlyopposite to the Department of State, will undertake, with his accustomed zeal and diligence, the settlement of claims generally; and more particularly claims before Congress, against the United States, or the several Departments thereof, and before any board of commissioners that may be raised for the adjustment of spo- liation or other claims. He has now in charge the entire class arising out. of French spoliations prior to the year 1800-; with reference to which, inaddition to a mass of documents and proofs in his possession, he has access to those in the archives of the Government. Claimants and pensioners on the Navy fund, &c. bounty lands, return duties, &c. &c. and those requiring life insurance, can have their business promptly attended to by letter, (post paid,) and thus relieve themselvesfrom an expensive and incon- venient personal attendance. Having obtained a commission of Notary Public, he is prepar- ed to furnish legalized copies of any required public documents or other papers. He has been so long engaged in the duties of an agent, that it can only be necessary now to say that economy and prompt attention shallbe extended to all business confided to his care; and that, to enable him to render his services and facilities more efficacious, he has become familiar with all the forms of office. teb 26-ly i1OR RENT.--The dwelling-house and grounds of the late Lewis G. Davidson, Esq. situated on the extreme right of the heights of Georgetown, D. C. and comprising every advantage most desirable in a private residence. The house is substantially built of brick, and is of two stories, and spacious, neatly furnished with garrets, having four large rooms on each floor, with wing for kitchen, servants' rooms, pantry, &c. Sta- bles, carriage-house, cow-house, and gardener's house, and other offices, all of brick, are attached. The lot covers an ex- tent of twenty acres and more, which is now under fine culti- vation as garden, orchards, grass lots, woodland, &c. The pros- pect from this residence, south, is perhaps more extensive than that of any other part of the heights, while it embraces a Very beautiful northern view, of which all the others are deprived. For terms, apply to R. R. CRAWFORD, on the premises. june 10-dtf A TEACHER WANTED to take charge of the Mont ocacy school, near the mouth of the river Monocacy, Montgomery county, Maryland. A single man, who is quali- fied to teach all the useful branches of an English education, and who can come well recommended for sobriety and atten- tion, wil meet with immediate employment and liberal compen- sation. The situation is healthy, and the neighborhood is con- sidered a good one. Letters addressed to Joseph J. W. Jones, William Truidle, Warren King, or to Benjamin White, pos- paid, will be immediately attended to. Letters addressed to Poolesville Montgomery county, Maryland. nov 21w4w ECOLLECTIONS ofa Southern Matron,by Mrs. Gilman, of Charleston, S. C. A Love Token for Children, by MrS. Sedgwick, with a great variety of JUVENILE BOOKS, just received from the North, and for sale at the lowest prices, between 9th and 10th street's, Pennsylvania avenue. R. FARNHAM. O HIO GAZETTEER, with a map-Just published and this day received, for sale by F. TAYLOR. Also, Wetmore's New Gazetteer of Missoari, with a laige map, 1837. Sherwood's New Gazetteer of Georgia, with a large map, 1837. ' Peck's New Gazetteer of Illinois, 1837. illinois in 1837, with a map. Gordon s New Gazetteer of the State of New York, 10 otavo volume. :' ' Martin's Gazetteer of Virginia and the District of Columbia, I octavo volume. '. Large Map of Florida, taken from the documents in the Land Office at Tallahassee. . Large Maps of Mississippi and Alabama, just engraved froln the United States Surveys in the General Land Office, Wash- ington City. Visit to Texas, 1 volume. Large New Maps of Illinois, Michigan, Wisconsin, &c. ex- hibiting the sections. SDavenport's New Gazetteer, 471 closely printed large octa- vo pages, handsomely bound,with many engravings, prige 1 50. New Geographical Dictionary, containing 304 closely printed pages, price 87 cents. And very many other works of the same class of literature, at the lowest price in every case. jan 3 Charles County, set. O N application to me, the subscriber, Chief Judge of the Orphans' Court of Charles county, (in the recess.of Charles County Court,) by the petition, in writing, of Dennis Nalley, of said county, praying for the benefit of the Act of Assembly for the relief of insolvent debtors, and the supple- ments thereto, a schedule of his property and a list of his cre- ditors, on oath, being annexed to his petition, and being satis- fied thai he has resided in the State of Maryland two years - immediately previous to his application, and having also stated that he is unable to pay his debts, and that he is now confined in jail for the same, do hereby order and- adjudge tlihat the said Dennis Nalley be discharged from cUgtqdy, and that he :give notice published in some newspaper once a week fur two months successively, in the District of Columbia, to his credit- ors, to appear before Charles County Court on the third Mon- day in March next, for the purpose of recommending a trustee for their benefit, and to show cause, if any they have, why the said Dennis Nalley shall not have the benefit of said'acts as prayed. Given under my hand, this .9th day-of Decembcr, 1837. JOHN FERGUSSON. True copy. Test: JOHN BARNES, dec 12-w2m Clerk of Charles County Court. ANIFOLD LETTER WRITERS.-W. FIS- IB 1CHER has just received an assortment of Wilson's su- perior Manifold Letter Writers, from five to ten dollars, enve- lopedcovers, steel mounted, with lock and key. dec 25 JUST PUBLISHED AND FOR SALE, by W. M. MORRISON, two doors west of Brown's Hotel, Peck's New Gazetteer of Illinois, in three parts, containing a general view of the State; a general view of each county, and a particular description of each town, settlement, stream, prairie, bottom, bluff, etc., alphabetically arranged; by J. M. Peck. Also, a second edition of Peck's New Guide for Emigrants to the West; containing Sketches of Michigan, Ohio, Indiana, Illinois, Missouri, Arkansas, with the Territory of Wisconsin and the adjacent parts. Tales from the German, translated by Nathaniel Green; in 2vols. Twice Told Tales, by Nathaniel Hawthorn.- The Youth's Keepsake, for 1838. The Harcourts, or Stories from Real Life, designed to teach true Independence and Domestic Economy; .in five parts. Part 3d: Extravagance is the disease, economy is the reme- dy."-Paulding. The Savings Bank, and other stories; illustrating true Inde- dependence and Domestic Economy; translated from the French by a Lady. Part 4: Stories from Real Life. The Lady's Annual Register and Housewife's Memorandum Book, for 1838; by Caroline Gilman; with Engravings, by Devereux. i dec 16 POEMS BY THE HON. MRS. NORTON,-In .one volume, price fifty cents, is just received. For sale y F. TAYLOR. nov 29 EOLOGY AND MINERALOGY.-A new sip- ply of Buckland's Geology and Mineralogy, 2 vols. new Lyell's Principles of Geology, 2 vols. De la Beche's Geological Manual Comstock's Mineralogy Do Geology, . Is received and for sale at low prices, at GARRET ANDER- SON'S Book, Stationery, and Fancy Store, Pennsylvania Avenue, between 11th and 12th streets, jan 8 th00 FOSTER'S COPY BOOKS.-Just re- 200 8 ceived from Boston, Foster's Elementary Copy Bookg, designed to render the acquisition of penmanship simple and progressive; to save teachers the trouble of setting copies, and to furnish schools and families with a practical system- lby which the art may be taught with facility and correctness. Also, Bascom's Guide to Chirography, in a series of writing books ; ruled, with the lines about one-seventh of an inch a pat; which style of ruling is adapted to coarse hand, medium hand, fine hand, capitals, &c.; with engraved copies in each book,, and general directions on the covers; being an improvementon the author's system of penmanship and writing book combined. - A considerable deduction will be made to those who buy by the quantity. For sale between 9th and O1li streets, Pennsylvania avenue. R. FARNHAM. dec 8 POCKET LEDGERS, &c.-W. FISCHER has in store English Pocket Ledgers, with and without locks and 1 I' i A i 1 -A 1 -- A 1 - STEWART, THORNTON, AND EASTON, Attorneys and Counsellors at Law, and Solicitors in Chancery, MOBILE, ALABAMA. GEORGE N. STEWART, HARRY I. THORNTON, SWM. C. EASTON, Postage to be paid on business letters. oct 17-d&cly BECKWITH'S ANTIDYSPEPTIC PILLS.- For the most part, those who are already dyspeptic, or by -their habits and pursuits in a fair way to become so, are com- monly not much in doubt of the fact, and sufficiently disposed to employ a remedy entitled to their confidence. The object of this advertisement is, to offer to those who may require a medi- cine of this kind, such weight of testimony as will satisfy any reasonable mind that, under all circumstances, these pills may be tried with safety, at least. It is presumed such evidence as the following would be thought sufficient to establish much more important matters: From the Rt. Rev. Levi S. Ives, D. D. Bishop of North Carolina. "RALEIGH, MARCH 2, 1835. SHaving for the last three years been intimately acquainted with Dr. John Beckwith, of this city, and enjoyed his profes- sionaf services, I take pleasure in stating that his character as a Christian gentleman and experienced physician, entitles his testimony, in regard to the use of his Antidyspeptic Pills, to the entire confidence of the Public. My experience of the good ef- fects of these Pills, for two years past, satisfies me of their emi- nent value, particularly in aiding in impaired digestion, and warding off bilious attacks. Having been for a long time sub- ject to the annual recurrence of such attacks, I was in the habit of resorting for security against them, and with very partial success, to a liberal use ofcalomel or bluepill. But since my acquaintance with the Antidyspeptic Pill of Dr. Beckwith, which 'he prescribed in the first instance himself, I have not been un- der the necessity of using mercury in any form, besides being wholly exempt from bilious attacks. Several members of my family are experiencing the same beneficial effects. "L. S. IVES." From the Rev. F. L. Hawks, D. D. "NEW YORK, FEB. 3, 1836. "I have no knowledge, derived from experience, of the effi- cacy of Dr. Beckwith's Pills; but I know that several of my personal friends in North Carolina, whom I left some years ago suffering severely under dyspepsia, were in good health when I saw them, on a visit made a few months since, and all ascrib- ed their recovery to the use of Beckwith's Pills. "I know that the certificates obtained by the Doctor in North Carolina are from gentlemen ofthe highest respectability, and several of them stated to me verbally that which is contained in their published certificates. I have the most entire confi- dence in them. S"I also know Dr. Beckwith, and have known him from my boyhood; and I cheerfully state, with Bishop Ives, 'that his character as a Christian gentleman and experienced physician, entitles his testimony, in regard to the use of his Antidyspeptic Pills, to the entire confidence of the Public.' F. L. HAWKS." From Governor Iredell. "AUGUST 21, 1834. -"DIr. Beckwith's Antidyspeptic Pills have been used in my Inily, which is a large one, with the most beneficial effects. A number of my friends who have been afflicted with dyspepsia ajd.othler disorders of the stomach, have spoken to me in strong terms of the relief they experiened'from this remedy. With- out the evidence I have received from others, my intimate ,knowledge of the professional and private character of Dr. Beckwith, for the last twenty years, justifies me in declaring that he would give no assurances of facts of his own experience, or of professional deductions, of which he was not perfectly confident, and on which the Public might not safely rely. "JAS. IREDELL." From the Hon. George E. Badger, LL. D. "RALEIGH, NOV. 7, 1834. "For several years past, Dr. Beckwith's Antidyspeptic Pills have been used as a domestic medicine in my family. I have myself frequently used them for the relief of headache, acid, and otherwise disordered stomach, resulting from imprudence or excessin diet, and I have had many opportunities of learning from others their effects, when used by them for like purposes. My experience and observation justify me in saying that the re- lief afforded by the Pills is generally speedy, and almost al- ways certain ; that they may be taken at any time without dan- ger or inconvenience, and that their operation is attended by no nausea or other disagreeable effects whatever; and though I have known many persons use them, I have known none who did not approve them; none who sustained any injury, and none who failed Lo derive benefit from their use. And, upon the whole, I do.not hesilate to recommend them as an agreeable, safe, and efficacious remedy in dyspeptic affections, and believe them my- self to be the best antidyspeptic medicine ever offered to the Public. "G. E. BADGER." From the Hon. Richard Hikes, late member of Congress from the Tarboro' district. HERMITAGE, near Sparta, Edgecombe co. Nov. 10, 1834. I was severely afflicted for several years with dyspepsia, jaundice, and general ill health. I called in the aid of eminent physicians, and visited most of the mineral springs of celebrity wa; thought to be hopeless. Being ee in mellin the winter of 1824 to spend some weeks in Raleigh, I consulted Dr. Beck- with, when he prescribed what is now known as 'Beckwith's Antidyspeptic Pills,' by the use of which I soon became much better. I continued to take them for some months, .until my health was entirely restored, to which they mainly contributed. Another member of my family subsequently used them with like benefit'and success. Having been many years well acquainted with Dr. Beck- willh, I take pleasure in mentioning him as a gentleman of great worth and intelligence, and of known and admitted science and skill in his profession, and in recommending his Antidyspeptic Pills as a most valuable medicine to those afflicted with the diseases I have mentioned. "RICHARD HINES." From the Hon. Charles Fisher, late member of Congress, Salisbury district. "SALISBURY, FEB. 23. 1837. ' "S ?veral years ago I was very much afflicted with diseased rnomach and bowels; nothing I could eat appeared to agree with -ine, and I was obliged to be very careful in my diet. A jour- rey to the Southwest afforded me considerable relief, and, as 1 supp,''-.l.d, had cured me ; but, when I left off travelling, the disease returned again, and I was obliged to take medicine x-onstanfly, among -other things very often calomel; this con- tinueid to be my state until about twelve months ago, when, on tle recommendation of Major John Beard, I began to try Beck- with's Antidvspeptic Pills; I soon found relief from them, and since have taken no other medicine whatever. Whenever I find my stomach or bowels becoming deranged, I resort to these Sp;ll, and invariably find relief. I have heard a number of persoiis speak of the benefits they have received from these pills, in the most decided terms. I am well acquainted with Dr. Beckwith ; he for a time resided in this place, and was my fiamini physician. His own testimony with regard to the use of his Antidyspeptic Pills may be fully relied on. CHARLES FISHER." These Pills may be had at the stores of Dr. W. GUNTON and S. J. TODD, Washington City; R: STABLER, Alexan- Sdria; O. M. I NTHICUM, Georgetown, and of almost every extensive Druggist throughout the United States. sept2-d6m dec 4-d4m, ASH' FOR NEGROES.-- will give the highest cash price for likely NEGROES from 10 to 25 years of age. Myself or agent can at all times be found at the estab- lishment formerly owned by Armfield, Franklin & .Co. at the west end of Duke street, Alexandria. mar 14-tf GEORGE KEPHART. F IFTY DOLLARS REWARD.-Eloped frotnmy V residence ELOIZA, a young negress of ordinary stature and size, but strongly made, about 22 years old, color of a chest- nut or brown, long thick woolly hair, which is commonly neat- ly combed, parted before, and tucked with combs. Her cloth- ing consists of several calico frocks, white cotton aprons and collars, &c. and a black bombasin dress. She has had from her birth a very singular mark, resembling the dashing on the skin of coffee grounds or some black substance. This mark, to the best of my recollection, commences on the neck or collar boneand covers part of her breasts, body, and limbs, and when her neck and arms are uncovered is very perceptible. I un- Sderstand that she calls herself Louisa, and has been frequently seen east and south of the Capitol square, and harbored by ill- - disposed persons of every complexion for her services, where by diligent search she may be found, unless she has hired her- self elsewhere as a cook or house servant. I will give the above reward if caught in the District of Columbia and deliver- ed to me, or if out of the District I will give an additional sum often dollars for every ten miles beyond the District line in any direction, provided the distance does not exceed fifty miles, and if beyond that distance one hundred dollars, and secured so that I get her again, in case it should not be convenient to de- liver'her as aforesaid. WM. ROBINSON, oct 2-dtf Georgetown. W HIG ALMANAC.-The Whig Almanac and Politi- cal Register, for 1838, containing full tables of the votes for President in the several States, by counties, compared with the votes cast in the same States arid counties during the last F tR SALE.-A First-rate Carriage and harness, and a YELLOW PINE AND WHITE OAK TIMBER. pair of well-rwatched carriage horses. They may be seen at-Smith's Livery stable, who will give any information that NAVY COMMISSIONERS' OFFICE, may be desired, and will state the terms of sale. JANUARY 4, 1838. dec 20-dtf ROPOSALS, sealed and endorsed, will be received at F O CLAIMANTS FRANCIS A. DICKINSt of thoe K. this office until three o'clock P. M. on the third day of ' cit CLAIMANTS.-FRANCIS A. DICKaINS, of tintme February next, for the following Yellow Pine and White Oak Shd city of Washington, having resigned the appointment timber, deliverable at the Navy Yard, Gosport, Va. held by him for several years in the Treasury and War Depart- No. 1. One set of yellow pine beams, for a frigate of the ments, has undertaken the agency of claims before Congress, first class. and other branches of the Government, including commission- No. 2. Two sets of yellow pine beams, for sloops of war, crs under treaties, and the various public offices; also, the pro- first class. curing of patents for public lands, prosecuting claims for servi- No. 3. Twenty thousand cubic feet of yellow pine plank ces in the Revolution, and for Navy pensions, and generally 'stocks. such other business as may require the aid ofan agent at Wash- No. 4: Twenty thousand cubic .feet of yellow pine plank ington. He will likewise attend to the prosecution of bounty stocks. land claims upon the State of Virginia, and the recovery of No. 5. Twenty thousand cubic feet do. do. do. lands in Ohio which have been sold for taxes. No. 6. Twenty thousand cubic feet do. do. do. Persons having, or supposing themselves to have claims, will, No. 7. Twenty thousand cubic feet do. do. do. on transmitting a statement of the facts, be advised of the pro- No. 8. Twenty thousand cubic feet white oak plank stocks. per course of proceeding. His charge will be moderate, de- The beam pieces and one half of the plank stocks to be de- pending upon the amount of the claim and the extent.of the slivered on or before the 30th April, 1839, and the other half of service the plank stocks on or before the 30th April, 1840. He is also agent fo the American Life Insurance and Trust Persons offering will make their offers separately for the Company, which has a capital of two millions of dollars paid in, quantities and kind of timber embraced in any of the above and for the Baltimore Fire Insurance Company. numbers, and they willbe considered and decided independ- Mr. F. A. DICKINS is known to most of those who have been entlof each they in Congress within the last few years, or who have occupied Schedules of the beam pieces will be furnished on applica- any public situation at Washington. tion to the Commissioners of the Navy, or to the Commandant His office is on Pennsylvania Avenue, adjoining the building of the Navy Yard, Gosport, Virginia. occupied by the Treasury Department, and opposite to those oc- The yellow pine beam pieces and plank stocks must be the cupied by the Post Office Department. best quality long leaf fine grain, heart, Southern yellowpine =r All letters must be post paid. july 6-dly timber. The white oak plank stocks must be of the best RY GOODS--As the season is advanced, we have quality, and must have grown on lands situated near to salt come to the determination to dispose of our entire stock water, or within the influence of the sea air; and the white oak of Goods, at very reduced prices, which consists of- and yellow pine rlank stocks must have been girdled or felled Silks, Linens, Cloths, Cassimeres, Vestings between the twentieth day of October and the twentieth day Hosiery, Gloves, Merinoes, Blankets of March next preceding the deliveries ;all of which must Calicoes, Sheeting,'Diapers, Table Cloths be proved to thie satisfaction of the commanding officer of the And a good assortment of Carpeting and Curtain Goods. said Navy Yard, Gosport, Virginia. BRADLEY & CATLETT. All the said timber must be free from sap, heart shakes, dec 30-eo3w (Glo.&Mad.) wind shakes, and all other defects. The plank stocks must average forty-five feet in length, and J ADY BLESSINGTON'S MAGNIFICENT none of them must be less than thirty-five feet long; the white S ANNUAL.-Gems of Beauty, displayed in a series oak planrk stocks must square not less than fourteen inches at of 12 highly finished engravings of The Passions, from designs the but, amd may square one-fourth less at the top; the yellow by E. T. Parris, Esq. executed under the superintendence of pine plank stocks must square not less than fourteen, nor more Mr. Charles Heath, with fanciful illustrations in verse, by the than sixteen, inches at the but, and may square one-fifth less COUNTESS OF BLESSINGTON. One splendid volume, imperial at the top. quarto, superbly bound in rich figured silk, and gilt Turkey Ten per centum will be withheld from the amount of each morocco, in a variety of styles. The exquisite taste of the fair delivery made, as collateral security, in addition to the bonds editress is conspicuous in the perfection of this beautiful annual; given, to secure the performance of the respective contracts, the illustration's, which include a wider range of subjects than which will in no event be paid until the contracts are complied those of last year, have never been equalled for high finish and with in all respects. delicacy of execution, and the general style of binding, and Ninety per centum will be paid within thirty days after the "getting up," is such as to give it a decided superiority over bills for the timber shall be approved and presented to the every other publication of the season. Navy Agent. THE AUTHORS OF ENGLAND, a series of Medallion All of the said timber must be subject to inspection and Portraits of modern literary characters, engraved from the measurement by the inspector and measure of timber at the works of British artists, by Achille Collas, with illustrative no- said Navy Yard, Gosport, or by such other person or persons tices by Henry F. Chorley-one splendid royal quarto volume, as may be designated by the Commissioners of the Navy for richly bound. the performance of that duty; and in all cases the timber must FLORA'S GEMS, or the. choicest Treasures of the Parterre, be in all respects to the acceptance and satisfaction of the con- containing 12 bouquets of flowers, drawn and colored in the manding officer of the said Navy Yard, and approved by him. most finished and delicate style, so as to equal first-rate draw- jan 6-d ings, with poetical Illustrations, by Miss L. A. Twamley. Im- ij;To be published in the National Intelligencer, Globe, perial quarto, richly and appropriately bound in green and gold. Army.and Navy Chronicle, Baltimore Republican, Norfolk - PEARLS FROM THE EAST, or Beauties of Lalla Rookh, Herald, Norfolk Beacon, Raleigh Star, and Newbern Sentinel. designed Dvy anny Cuorbaux, drawn on stone by LIouisa Uor- baux, containing 12 splendid illustrations, on tinted paper, or may be had superbly colored under the artist's inspection. Im- perial quarto. FLOWERS OF LOVELINESS-Twelve groups of female figures, emblematic of Flowers, forming an assemblage of fe- male beauty, designed by various artists, with poetical- illustra- tions, by L. E. L. Imperial quarto, handsomely bound in moreen. THE BOOK OF GEMS, 1838. The Poets and Artists of Great Britain, edited by S. C. Hall. Third volume, completing the work, and containing specimens and memoirs of the modern Poets of GreatBritain, and 43 exquisite Illustrations. 1 vol 8vo. The same work for 1837 and 1836, altogether probably one of the most attractive books in existence. Also, over twenty Souvenirs, of various kinds not enumerated above, English Bibles of all sizes, superb Prayer Books, Draw- ing Books, and Albums, in great variety. Books of Engravings of many different kinds, Gold Pencil Cases, Portfolios in splen- did ending, Ladies' writing desks, Ladies'- work Boxes, Bronze Inkstands. Motto Seals, Gentlemen's Dressing Cases, Colored Toy Books. Books for young People, Juvenile Souvenirs, &c. &c. with many other articles suitable for the present season, in the great- est variety and all at the lowest prices, for sale by F. TAYLOR, At the Waverly Circulating Library, immediately east of Gadsby's Hotel. jan 1 Circuit Court of the District of Columbia for tlhe County of Washington.-In Chancery. Auguste R. Theriot, The Mayor, Board of Aldermen, and Board of Common Coun- cil of the City of Washington, the heir or heirs at law of Peter Passet, late of said city, deceased, and Paul Kinchey, Administrator of said Passet. HE bill in this case states that at a public sale of certain lots in the city of Washington, held by the Corporation of said city on the 3d April, 1826, by virtue of an act of Con- ,gress entitled An act to authorize and empower the Corpora- tion of the city of Washiigton, in the I)istrict of Columbia, to drain the low grounds on and near the public reservations, and to improve and ornament certain parts of such reservations," the said Passet, and one William Fadeuilhe, became the pur- chasers of lot No. 31, in square A, in the said city, at the sum of$532 87J, on certain conditions of sale and improvement.
That they paid one-fifth of the purchase money in hand, and
the said Fadeuilhe shortly afterwards sold and assigned his
right, title, and interest in said lot to the said Passet, who paid
all the instalments of said purchase money, with the "interest
thereon, which became due in his lifetime, as they became
due, and died some time in the year --, leaving the fast two
instalments of said purchase money unpaid, and indebted to the
complainantin the sum of $151 25, besides interest, and also to divers other persons, leaving personal property insufficient to pay his debts. That said Passet did not leave any known heir, for devisee, capable of inheriting or taking the said lot or his interest therein, and that he died intestate, and his heir or heirs at law, if any suchthere be, most probably reside in -- , whence the said Passet emigrated. The object of the bill is t, obtain a decree for the sale (subject to said conditions of im- provement) of all the right, title, and interest of said Passet, at the time of his decease, and of his heir or heirs at law, if any such there be, to said lot, for the payment of the complainant and the other creditors of said Passet. , Arid it appearing to the satisfaction of this Court, the heir or heirs at law of said Passet, if any such there be, reside without the jurisdiction of this Court, and most probably in France, it is thereupon, this 29th day of November, 1837, by this Court ordered, that notice of the substance and object of said bill be given to the -person or persons who is or are heir or 'heirs at law of said Passet, by publishing a copy of this order in the National Intelligencer once a week for six successive weeks ensuing, the heir or heirs at law of said Passet to be and ap- pear in the Clerk's office of this county at the rules therein to be held on the first Monday of April next, then and there to answer said bill, otherwise the same will be taken pro confesso against them : the first publication of this order to appear at least four months before said day. By order of the Court: Test: WM. BRENT, Clerk. dec 4-law6w McGCULLOCH'S COMMERCIAL DICTIONA- RY, latest edition, is just received for sale by : F. TAYLOR. Also. Loudon's Encyclopaedia of Plants. Loudon's Encyclopedia of Gardening. London's Encyclopaedia of Agriculture. Loudon's Eucyclopaidia of Cottage, Farm, and Villa Ar- chitecture. And many other valuable Eniglish editions. F' EXAS, in 1 volume, price 50 cents, describing the soil, productions, habits, advantages, &c. throughout those parts most interestingto American settlers, 262 pages. For sale by F. TAYLOR. jan 8 OST, on the llth instant, between the Capitol and Pre- sident's House, a small Pocket Book with between twen- ty and" thirty dollars, and several notes of hand, valuable to the owner, and also a silver Fruit Knife in it. It had also written in it, Mrs. Henrietta Nenner, No. 17 Harrison street, Baltimore. A suitable reward will be given if left at Mrs. Auld's boarding- house, Penn. Avenue. jan 12--3t ONDEIRS OF THEUNIVERSE.-Wonders of ihe Universe, Curiosities of Nature and Art, Won- derfirl and Eccentric Characters of every age and nation, An. ecdotes, Memoirs, Narratives, &c., in one octavo volume of 440. closely printed pages, handsomely bound, and illustrated with engravings. Price$1 25. Just received, and for sale by
jan 12 F. TAYLOR.
1 case assorted silk velvets for ladies' dresses.
1 case assorted silks, figured and plain
_- t .....- -_ -- _- . 1, J ...K 1. .,.;11 l,^ .1,-1 .,, ,,.^,, 11.T
O 'NEILL'S ANTI-RHEUMATIC MEDI-
CINE.-The transcendent merits, of this preparation, its
sanative powers and unparalleled efficacy in the cure of Rheu-
matism, &c. have voluntarily drawn forth the plaudits of thou-
sands, who byits use have been restored from pain and torture,
stiffness and decrepitude, to ease, strength, activity, and vigor-
ous health.
For sale by WM. GUNTON, only agent for the District.
jan 6-eol9t
Charles County Court, August Term, 183 7.
O RDERED by the Court, that the creditors of Charles Fer-
rall, a petitioner for the benefit of the insolvent laws of
the State of Maryland, be and appear before the Judges of
Charles County Court on the third Monday of March next, to
appoint a Trustee for their benefit, and show cause, if any they,
have, why the said Charles Feirall shall not have the benefit
of said acts. -Provided a copy of this order be inserted in some
newspaper published'in the District of Columbia, once a week
for two months before said third Monday of March'next.
True copy-Test: JOHN BARNES,
jan 6-w2m Clerk of Charles county.Court.
PARLEY'S -UNIVERSAL HISTORY.-Peter
Parley's Universal History, on the basis of Geography, for
the use of families; illustrated by maps and engravings, 2 vols.
square 16mo. royal.
This work is an attempt to present an outline of Universal
History in a form so attractive and agreeable as to, accomplish
the desirable object of imprinting on the minds of youth, in
bright and unfading colors, a clear outline of the story of man-
kind. tThe author has endeavoredto avoid bewildering diffuse-
ness on the one hand, and repulsive chronological brevity on
the other, and to present, in a small compass, a continuous tale
of the great human family-one that may be both comprehen-
sible and entertaining to the young reader. The work is print-
ed and bound in a superior manner. Just published and for
sale between 9th and 10th streets, Pennsylvania Avenue.
nov 10- 0 R. PFARNHAM.
OLD PENCIL CASES.-A large assortment of
L Gold aid Silver Everpoint Pencil Cases, Addisdn & Co's.
improved manufacture; just received and for sale at very low
prices at GARRET ANDERSON'S
Book, Stationery, and Fancy Store, between 11th & 12th
streets, Pennsylvania Avenue. jan 8-3t
IN CHANCERY, 29th DECEMBER, 1837.
O RDERED, That-the sales of the real estate of Samuel
Childs, deceased, made and reported by John D. Bow-
ling, the trustee, be ratified and confirmed, unless cause to the
contrary be shown before the first day of March, 1838 : Pro-
vided, That a copy of this order be published in some newspa-
per at least once in each of three successive weeks before the
29th day of January, 1838.
The report states the amount of said sales'to be $4,881. . True copy-test: RAMSAY WATERS. jan 2-law3w Reg. Cur. Can. l~pHE TOKEN FOR 1838, beautifully embellished S and enlarged to the size of Jennings's Landscape Annual, and bound in a superior manner in goat-skin morocco; and, as it regards mechanical execution, and its literary merits, far sur- passes any of its predecessors. For sale between 9th and 10th streets, Pennsylvania avenue. R. PARNHAM. OTICE.-By virtue of an order from the Orphans' .iN Court of Charles county, Maryland, I hereby give notice that I have obtained fromniaid Court letters of administration oi the personal estate of Ann Maria Murdock. All personstiav- ing claims against the ~aid Ann Maria Murdock are hereby no- tified to exhibit the same to the subscriber, on orbefore the 1st of July next, or they may be excluded from all benefit of said estate. PETER W. RAIN, jan 3-w6w Administrator of Ann Maria Murdock. HIS IS TO GIVE- NOTICE that the subscriber. t hath obtained from the Orphans' CourtofWashington county, in the District of Columibia, letters ofadministration on the personal estate of William R. Maddox, late of Washington county, deceased. All persons having claims against the said de- ceased are hereby warned to exhibit thesame, with the vouch- ers thereof, to the subscriber, on or before the 3d day of January next; they may otherwise by law be excluded from all be- nefit of said estate. Ani all persons indebted to- said estate are hereby requested to-make immediate payment. : SGiven under my hand this 3d day of January, eighteen hun- dred and thirty-eight. E. SELIZABETH F. MADDOX, jan 4-w3w Administratrix. ANDI FOR SALE.-The subscriber will sell at pri- L vate sale all or any portion of the real estate of the late Thomas Cramph'in, remaining unsold at this time, consisting of several farms in Montgomery county, Maryland, distant only ten or eleven miles from'Washington City or Georgetown. , Anydescription of this property is deemed unnecessary, as it is presumed that those wishing to purchase would examine for themselves, and they are referred for any further informa- tion on the subject, to Charles B. Calvert National- Hotel, ,Washington City. GEORGE CALVERT, sept 19-2awtf Trustee. SARD CASES.-W. FISCHIlR has opened a very large -L assortment of the handsomest Card an'd'Needle Cases, of, silver, pearl, ivory, and tortoise;shell, that has ever been offer- ed for sale in the city. 1BYRON'S WORKS.-The works of Lord Byron, in- eluding the suppressed poems. Also, a Skttch of his Life, by J. W. Lake, complete in' IPol. handsomely printed and bound. ---'; Cowper's and Thompson's "Works.-The works of Thompson and Cowper, including many letters and.poems ne- ver before published in this country,'with a new interesting memoir of the Life of Thompson, complete in one volume. The poetical works of Milton, Young, ,Gray, Beattie, and Collins, complete in I volume. - The poetical works of Rogers, Campbell, I. Montgomery, Lamb, and Kirk White, complete in I volume. The works of Lawrence Sterne, with the Life of the Author, written by himself, in 1 volume. Mackenzie's Five Thousand Receipts in all the useful and Daily national intelligencer ALL ISSUES CITATION SEARCH THUMBNAILS MAP IT! PAGE IMAGE ZOOMABLE Full Citation STANDARD VIEW MARC VIEW Permanent Link: http://ufdc.ufl.edu/UF00073214/00008 Material Information Title: Daily national intelligencer Alternate title: National intelligencerSunday national intelligencer Physical Description: v. : ; 50-60 cm. Language: English Publisher: Gales & Seaton Place of Publication: Washington City D.C. Creation Date: March 28, 1837 Publication Date: 1813- Frequency: daily (except sunday)[feb. 6, 1865-]daily[ former 1813-feb. 5, 1865]dailynormalized irregular Subjects Subjects / Keywords: Newspapers -- Washington (D.C.) ( lcsh ) Genre: newspaper ( marcgt )newspaper ( sobekcm ) Spatial Coverage: United States -- District of Columbia -- Washington Coordinates: 38.895111 x -77.036667 ( Place of Publication ) Notes Citation/Reference: Brigham, C.S. Amer. newspapers Additional Physical Form: Also available on microform from Readex Microprint Corp., and on microfilm from the Library of Congress. Dates or Sequential Designation: Vol. 1, no. 1 (Jan. 1, 1813)- Dates or Sequential Designation: Ceased in 1869. Numbering Peculiarities: Suspended Aug. 24-30, 1814. Record Information Source Institution: University of Florida Rights Management: All rights reserved by the source institution and holding location. Resource Identifier: oclc - 02260099lccn - sn 83026172 System ID: UF00073214:00008 Related Items Related Items: Weekly national intelligencer (Washington, D.C.) Related Items: National intelligencer (Washington, D.C. : 1810) Related Items: Universal gazette (Philadelphia, Pa. : Nov. 1797) Succeeded by: Washington express Succeeded by: Daily national intelligencer and Washington express Full Text A -, I- ~-t-~-t---~- - !&i1ll tz'iLtJ~injci~~ SVOL. XXV. PUBLISHED BY GALES & SEASON. PR(GE, FOR A YEAR, TEN DOLLARS ; FOR SIX MONTHS, SIX DOLLARS. PAYABLE IN ADVANCE. Those subscribing for a year, who do not, either at the time of ordering the paper, or subsequently, give notice of their wish to havo the paper discontinued at the expiration of their year, will be presumed as desiring its continuance until counter- manded, and it will be continued accordingly, at the option of the Editors. RAILROAD ARRANGEMENT. Until further notice the cars will depart as follows: 1From Washington for Baltimore, AT HALF PAST NINE O'CLOCK A. M. AND AT HALF PAST THREE O'CLOCK P. M. From Baltimore for Washington, AT NINE O'CLOCK A. M. AND AT A QUARTER PAST THREE O'CLOCK P. M; dee 28-d6t&w6t [Alex. Gaz. & Met.] CANAL PACKET OFFICE, GEORGETOWN, MARCH 20, 1837. T HE Packet Line is now in operation between Georgetown and Shepherdstown, via Harper's'Fe'riy,' for the present, leaving the former place on Monday, Wednesday, and Friday, and the latter on Tuesday, Thursday, and Saturday. On and after the 3d of April the trips will be daily (Sundays exdepted) from each place. Hours 'of starting 4 o'clock, A. M.: fare brought 83 50, intermediate distances five cents per mile. J. I. STULL, mar 21-dt3dAp Treasurer. FOR NORFOLK.-The Steamer CO- LUMBIA, Captain James Mitchell, having been placed permanently on the route between the Districtof Colum- bia and Norfolk, will leave Washington every- Thursday at 10 o'clock, A. M. and, returning, will leave Norfolk every Sunday at 3 o'clock P. M. The Columbia arrives in time tor the Charlesto .,at'ts, Ports- mouth Railroad, and the James river boats. Passage and Fare$8.
Freight destined to Petersburg or Richmond, must be paid
for at the time of shipment. (Globe) mar 10-tf
SUMMER ARRANGEMENT.
THREE TIMES A WEEK.
Passage to Norfolk, Peters-
burg, and Richmond.-Onand
after Monday, the 13th instant, the
steamboat Kentucky will make
two trips a week to Norfolk, leaving the lower end of Spear's
wharf, Baltimore, every Monday and Friday afternoon, at 2
o'clock. Returning, will leave Norfolk every Sunday qnd
Wednesday afternoon.
The Columbus will leave the same wharf every Wednesday
afternoon, at sarte hour, and, returning, will leave Norfolk every
Friday afternoon, weather permitting; will put passengers on
board the Philadelphia boat next morning.
These boats run in connexion with the Charleston steam
packets, and the James river steamboats for Petersburg and
Richmond. Passage and fare 88.
All baggage at the risk of the owners.
JAMES FERGUSSON, Agent, -
mar 23-2aw. Baltimore.
PASSAGE FROM NOR-
FOLK TO CHARLESTON,
S. C.-The superior steampackets
South Carolina and Georgia will
commence to run weekly on Saturday, the 18th instant, and
will continue to leave Norfolk every Saturday, after the arrival
of the boatfrom Baltimore.
Returning, will leave Charleston every Friday, and, unless in
bad weather, passengers may arrive in New Cork on Monday
right.
Passengers leaving- New York on Thursday, and Philadel-
phia on Friday, will arrive in Norfolk in due time for the abore
packets..
Passage and fare $25 on and after the 18th. All baggage at the risk of the owners. Apply to DICKSON, HUNTER & HIPKINS, Norfolk. JAMES FERGUSSON, Baltimore. WILLIAM PATTON, Charleston. mar 23-2aw V ERY EXTENSIVE SALE.-O:n Saturday, the 1st of April, at 12 o'clock M. I shall sell at auction, without reserve, at the National Hotel Livery Stables, the very exten- sive and valuable stock of Carriages, Barouclies, &c. with the fine harness and saddle Horses belonging to the above estab- lishment, viz. Handsome close Carriages and Coaichees, with harness Do brass and silver mounted Barouches, with do Do light buggy Wagon, with do Five pairs of well broken harness Horses, in good condition, ad have been carefully used. Amongst these are pairs ofihand- ome match Horses, with several valuable saddle Horses. Also, Saddles and Bridles, stable furniture, &c. The carriages and barouches are in first-rate order, built in ie most modern style, and of the best workmanship and mate- als. Any one desirous of making a purchase of the above in one tire lot, or a part thereof, has an opportunity of doing so at -ivate sale previous to the 1st of April. EDWARD DYER,' mar 25-d&cpts Auctioneer. IY EDWARD DYER--GENTEEL HOUSE- HOLD FURNITURE.-On Friday next, 31st ;it at 11 o'clock A. M. I shall sell at the residence of Mr. J. Wilson, on F street, west of the Navy Department, his house- Id and kitchen furniture, which is genteer and well kept, isisting of, viz. Parlor and chamber Carpets and Rug Window Curtains, mahogany Sideboard Hair Sofa, gilt mantel Glass Handsome seat and Windsor Chairs Passage and step Carpets, hall Lamp Dining and breakfast Tables Crockery and China, Glassware - Set ivory Knives and Forks, &c. French post Bedsteads, Beds WVashstands end other articles of chamber furniture Kitchen articles generally, Refrigerator, &c. erms at sale. EDW'D DYER, ar 25 (Globe) Auctioneer. VALUABLE FARMS AT PRIVATE SALE.- The subscriber will sell at private sale all or any portion e real estate left by Thomas Cramphin, deceased, remain mnsold at this time, consisting 6f the late residence of said uphin, and otlber lands adjoining, together with two or very valuable Farms on Rock ereehk. et Dwelling-house-Faarm is situated about eleven miles Washington, on the Washington and Rockville turnpike and contains 375.; acres of land, a large portion of which wood. The improvements consist of 'a brick dwelling- : nearly new, with all the necessary out.-buildings. -se Rock creek Farm, situated six miles from Georgetown diately on the Georgetown and Reockville turnpike road, of the most valuable and desirable farms in the county, composed of a large portion of the finest timber and mea- ind. The improvements consist of a commodious frame ng-house, and all the necessary out-houses. se lands have been recently surveyed, and laid off into of from 200 to 400 acres; but should it be found advanta- for the disposal of them, they will be subdivided to suit :sers. Any communications addressed to the subscriber, lensburg, or left at the National Hotel, Washington, will rnptly attended to. GEORGE CALVERT, 21-dtf Trustee. /T AND COAL.-The cargo'of the ship Caledonia, ipt. Coffin, from Liverpool, now arrived in the river, is for sale, either the entire cargo or in lots to suit to pur- SIt consists of -00 sacks of blown or stowed Salt 00 do. Ground Alum do. to 14,000 bushels Ground Alum Salt, in bulk, and 10 bushels Orrell Coal, for grates. Apply to WALTER SMITH, Georgetown. !2-d2w PICE.--The undersigned, Commissioners appointed r Prince George's County Court to value and lay off er of Margery Daral in andto to e lands of Richard ceased, late of Prince George's county, according to isions of the acts of Assembly in such case made and do hereby give notice to all concerned, that they will , him late residence of Mr. Richard Hill, on the 4th day or thereabouts, at 10 o'clock, to correct the mistake made in assigning Mrs. Margery Darnall's dower to WILLIAM F. DEAKINS, THOMAS HARVEY, WILLIAM B. GAILER, JOHN ANDERSON, BENJAMIN- 0. LOWNDS, -w4w Commissioners. 1,300,000 INDIAN RATIONS. WAR DEPARTMENT, OFFICE INDIAN AFFAIRS, March 10, 1837. P ROPOSALS will be received at Cincinnati, Ohio, until 12 o'clock M. on the 10th day of April next, for furnishing, forlthe use of the Chickasaws, one million three hundred thou- sand Indian rations ; one hundred thousand to be delivered at Memphis, Tennessee, on or before the 10th day of.May, two hundred thousand at Little Rock, Arkansas, on or before then 20th day of May, and one million at Fort Cofflee, on the Arkan- sas river, on or before the 30th day of May next. The Indian ration consists of- 1. One pound of fresh beef or pork, or three-fourths of a pound of salt pork. 2. Three-fourths of a quart of corn or corn meal, or one pound of wheat flour. 3. Four quarts of salt to every one hundred rations. The rations, which must be of the first quality, must be de- livered in good order, at the points indicated, without expense to the Uni'ed States, to the agents of the Government, who will be stationed there for the purpose of inspecting and receiving the same. Bids may be made for each delivery, separately, but no bid for less than the whole amount wanted at each place will be considered. Approved security, in a penalty of double the amount of the accepted bid or bids, will be required. The privilege of rejecting all the bids, if deemed too high, is reserved to the Government. Payments will be made by drafts on this office, accompanied. by the certificate of the agent receiving the rations, as to the delivery of the same in accordance with the contract. No ad- vances will be made. The proposals must be sealed and endorsed "Proposals to furnish Chickasaw rations," and directed to Lieut. J. D. SEA- RIGHT, U. S. A. Cincinnati, Ohio, who, or some other officer of the Government, will open and declare the bids on the 10th of April, and close the contracts. C. A. HARRIS, Q Commissioner Indian Affairs. Inr To be published daily till the 10th April, in the Republi- fan and Advertiser, Cincinnati, and Hemisphere, Columbus, Ohio, Gazette, Lexington, Monitor, Maysville, and Advertiser, Louisville, Kentucky, and the accounts, with one copy of each paper, presented to Lieut. Searight for payment. mar I 1-dtl0thAp C. A. H. 25,000 BUSHELS OF RICHMOND COAL. NAVY AGENT'S OFFICE, WASHINGTON, MARCH 18, 1837. P ROPOSALS will be received at this office until the 5th of April next, for twenty-five thousand bushels of Richmond Coal, to be delivered at the Navy Yard in this city. One-third part, at least, must brseoa coal, and the remainder may be fine -coal for smiths' use. The quality must be equal to the Black Heath Company of Colliers" Coal. Part of thie Coal will be wanted in the early part of next month, and the remain- der on or before the first day of October next. Ten percentum will be withheld from the amonuntof each de- livery until thie contract is fully complied with, in ad hition to the bond'with the sureties given for the faithful performance of the contract. tir To be published daily in the National Intelligencer, Globe, and Richmond Enquirer. mar 22-dtA5 P[ROPOSALS will be received by the undersiga- ed, through the Post Office at Philadelphia, till the 25th of April, for furnishing the United States witll the following Yel- low Pine Lumber, viz. 3,000 running feet of 12 inches square, in lengths of 32, 38, 44, and 50 feet in equal proportions. 60 pieces, 12 inches square, 22 feet long. 100 pieces, 6 inches by 12,23 feet long. 30,000 feet (board measure) of 3 inch plank. The above to be delivered on the beach near Lewes,. Dela- ware, Cape Henlopen, one-third in May, one-third in June, and the remainder in July. The whole of the above to be'free of sap. For any further information, apply to the-undersigned, or to Lieut. F. A. Smith, of the Corps of Engineers, Lewes, Dela- ware ... R1CHD. DELAFIELD mar 25-dt24A ". Captain of Engineers. P ROPOSALS will be received by the undersign- .X ed, through the Post Office at Philadelphia, till the l7th of April, to furnish the United States with 350 White Oak Piles, 26 feet long and 12 inches square. Also, 30 White Oak Tim- bers for capping, 25 feetlong and 12 inches square. To be de- livered at the beach near Lewes, Cape Henlopen, one-third in May, one-third in June, and the remainder in July. For any further information, apply to the undersigned or to Lieut. F. A. Smith ofthe Corps of Engineers, Lewes, Delaware. RICHD. DELAFIELID mar 25-dtl5A Captain of Engineers. STONE FOR THE DELAWARE BREAK- I WATER.-Proposals will be received by the under- signed, through the post office, (Philadelphia,) until the 15th of April, for the delivery, at the Delaware Breakwater, of Stone to the value of one hundred thousand dollars. The stone to be of the hardest and mostdurable kind. A preference will be gi- ven to that containing the least mica. One-third of the quanti- ty is required in pieces exceeding two tons (of 2,240 lbs.) weight, and the other two-thirds in pieces not less than one- quarter of a ton weight. The whole to be delivered on or be- fore the 15th day of November next. Proposals will be received specifying the rate per ton of each size for any quantities over one thousand tons. Payments made in this city, on producing evidence ofdelive- ry at the Breakwater, subject to a reservation of ten per cent. as security for the performance of the contract. For any more information apply to the undersigned, at his of- fice, 208 Spruce street, Philadelphia, or to Lieut. F. A. Smith, of the corps of Engineers, at the Breakvwater. RICHARD DELAFIELD, mar 18-dtl3thA Captain of Engineers. NAVY DEPARTMENT, MARCH 11, 1837. NOTICE.-All persons claiming to be placed upon the Navy Pension Roll are requested to send their papers to the Navy Department. All claims for arrears of Navy Pensions arc requested ta be forwarded to the Fourth Auditor of the Treasury for settlement. In all cases, the necessary instructions as to proof, &sc.will be promptly transmitted to claimantshby the Department and Fourth Auditor. This notice is given to prevent personal applications at the Department, and to save to the parties the expense and delay of employing agents. mar 14 -dimno APPAHANNOCK CANAL AND SLACK- WATER NAVIGATION.-Notice to Contrac- tors.-Sealed proposals will be received, until the 7th day of April next, by the subscriber, on behalf of the Rappahannock Company, at the office of their Engineer, in the town of Fred-. ericksburg, for the construction of four new Dams, raising, cov- ering, and backing several others, several short Canals, four- teen Lift Looks, of wood and stone combined, ten Guard Locks, and other incidental works, for that portion of the slack-water navigation extending from the town of Fredericksburg to Bar- nettl's mills, a distance of twenty miles. The prices for the work must include the expense of materials necessary for the completion of the same according to plans and specifications that will be ready for examination on the Ist to the 7th April, inclusive. The work to be completed by the 15th day of November of the present year. It is believed that the work above offered for contract presents superior inducements, especially to such as have been accus- tomed to, and prefer, contracts embracing heavy dry wallingand carpentry, the materials for which are at hand and in abund- ance. No fears need be entertained as to the healthfulness of the climate. The usual testimonials of character and responsibility will be expected to accompany the proposals. P. MARTINEAU, mnar 21-dt7thAp Chief Engineer. F TSH DOCKS.-The following sites have been estab- llished by law for the sale of fish, viz. The south extremity of 17th street west, on the Tiber ; the landing on thie north side of the Tiber at 7th and 12th streets west, provided no fish shall be cleaned on said landings; the steamboat wharf on the Potomac, near the bridge over the Polo- mac., and at Cana's wharf; 'Pront's wharf on the Eastern Branch ; the wharf owned or occupied by F. B. Poston, on the Potomac river, near the entrance of Rock creek in the same, and on theu south side ofTiber creek bn 151h street west; and the whartf now occupied by Messrs. F. B. Poston and Thomas Herbert, near tihe intersection of G and 27th streets west. No fish can be sold, between the 15th of March and 1st of June, out of any vessel, scow, or boat, at any other site or plmci in this city, under a penalty of 810, except at Ihe landings where they may be caught or taken in seines, or out of cars and wa- gons, and at the several market-houses. mar 13-1mo WM. HEWITT, Register. LANK BOOKS, STATIONERY, &c.-GAR- RETANDERSON has on hand a good assortment of Blank Books, Writing and Printing Paper, Tape, Taste, &P. which he will sell at a low rate. The Clerks in the Depart- ments and others purchasing Stationery, will do well to see his samples, and compare the prices with those of othcr dealers. For sale at P. Thompson's Old Stand, Pennsylvania ave:nue,- between Lith and 12th streets. feb 10 WASHI ING5TON: 'UESDA M, IIRCL TO TIHE LOVES OF DRY FEET! Keep the feet dry, the head cool, and bid defiance to the Physioiain.-Doct. Bocrhaavie. The subscriber need not expatiate on the above passage, which is taken from the works of the celebrated physician whose name is prefixed; lie is aware e hat an enlightened public will digest and bear its import in minJ, and thus give to it its due appreci- ation. The Journal of Health, published in Philadelphia in 1827, by an association of medical gentlemen, in giving a list of all the melancholy diseases that arise from wet feet, numbering thirty- nine, says tlhe fair and lovely of the land are cut down in the bloom and blossom of life, from diseases arising from wet feet, owing in a great meaiisure to the pride of youth, and the heed- lessness of old ago, thus depriving society ofsome of the bright- est orbs and greatest ornaments, and when such diseases have taken place, tie house is on fire, and danger is not far off."- Vol. 1, No. 6. The following is taken from the Medical Advocate. What causes the doctors to ride in their coaches ? Cold and wet feet. If, then, you would wish to dispense with their services, keep your feet dry." An ounce ofpreventative is worth a pound of cure." HJealth, the poor man's riches, the rich man's bliss." Doctor Franklin. The subscriber most respectfully informs the reader that he has superseded, by his late discovery, the alarming consequren- ces mentioned in the respectable journals above quoted, which discovery has been sanctioned by one of the most erudite socie- ties probably in the world, (the American Institute.) And after having undergone an ordeal of the-severest scrutiny and criti- cisem before the judges of said institution as to the public utility o.fhis invention, it awarded him the diploma in October, 1835, .and again in October, 1836, having thus twice borne its testi- mony to the excellence of his invention. With such testimony, he hesitated not in applying to the Government for an .exclusive right for the said discovery, which right has been granted, ac- cording to law, for the term of fourteen years from the 10th day of this month, for this most desirabledesideratum. Hispatented composition renders all kinds of leather completely impervious to water, and is a sure preventative against its breaking; and this latter property is in importance "equal to the former.. It wilt be useful to the currier, the boot maker, the carriage maker, saddle and har ness maker, the wall painter, in preserv- ing his patterns, and lastly to the contractors of the mails, in ren- dering the bags in which letters, packages, &e. are conveyed, completely impervious, which will be a saving of at least 25 per cent. The patent right is for sale. All communications address- ed to thei patentee (post paid) will be attended to. P. G. NAGLE, Railroad Hotel, near the Capitol, Penn. Av. N. N. The diplomas, patent right, certificates and speci- mens are now exhibiting as above. mar 1-dtf- STOCK OF MERCHANDISE FOR SALE and Taver Ibfor rent.-The subscriber, being anxious to retire from the mercantile business, offers for sale his Stock of Goods, consisting of merchandise generally. Also, for rent, the Store House, situated on the Washington Railroad, twelve miles from Washington. As to the advantages of this situation as a place of business, lie will satisfy any who may be disposed to buy him out. Also, for rent, is Taver'n stand, at the samdre place, (Belts- ville, Maryland.) The tavern is large, ready furnished, and conveniently constructed, with every necessary building at- tached, such as stabling, &c. The railroad cars stop at this place four times daily, to take in and put out passengers, and to receive and deliver produce. The situation is remarkably healthy; and t: any crs who -.ill properly carry en one or both establishments, offers great inducements. Terms will be very liberal, and possession given at any time. TRUEMAN BELT. P. S.-I am authorized to rent the Tavern stand in Bladens- burg, belonging to Mrs. H. Ross. The house, has been occu- pied a long time a tavern, and holds out inducements at this time, as passengers stop to and from the railroad. Possession given immediately, and rent moderate. TRUEMAN BELT, jan' 21-ceotf Beltsville, Washington Railroad, Md. OTICE.-Thle subscriber will sell from 1,000 to 12,000 cords of Pine Wood, standing on his plantation, near Har- ris's Lot Post Office, Charles county, Maryland, for the low suma of seventy-five cents per cord, or at a lower price, according to the number of cords wanted. The hauling, either to the Poto- mac or Wycomico rivers, is convenient; two and a half miles from the former, and two from the latter. Some of said pines are from twenty to sixty feet high, and free from knots, boughs, or limbs, nearly to the top, and from 8 to 12 inches square. M. LLOYD, Harris's Lot, Charles county, Maryland. feb 28-3taw3w F-INAL NOTICE TO DEBTORS.-All persons in- debted to Walter Harper, late of the City of Washington, Dry Goods Merchant, are requested to make immediate pay- ment to the subscriber. Those who have not yet made payment of their accounts may save the costs ofsuit, provided they do so on or before Monday next, the 27th instant, when all delinquents will either be proceeded against in the Circuit Court, or by warrant, without respect of persons. WILLIAM THOMPSON, Magistrate, No. 7, Louisiana Avenue, near the Bank of Washington. 4f Ladies, wishing to settle with the subscriber, can call at his dwelling, seven doors above his office. mar 21-1w (Glo.) A FARM FOR SALE-Situated in Prince George's county, Maryland, containing 270 or 280 acres. It lies in a very pleasant and healthy neighborhood, and is distant tenm miles from Washington city. lThe improvements are a two- story frame dwelling house, a two-story barn, the lower of stone; the stable joins the barn, so as to form a right angle, and the corn-house is connected with the stable, making it a very de- sirable place for cattle. It lies on the main road leading from Bladensburg to Good Luck post office, and can easily be recog- nised by two rows of locust trees leading from the road to the house. Clover, plaster, and lime have been used with great success. It certainly yields, in a great degree, to the growth of clover, timothy, and red-top. There are two meadows, one at tie head of a spring of very pure water, adjoining the barn, distant sixty yards friom the dwelling; the other in one of the fields, headed by four first-rate springs. The place is divided into six fields, and the barn being so centered as to receive the stock from either direction. This finm would suit a town gentle- man, for its local situation partakes of some variety. It has a large supply of- wood land, and a very handsome young apple orchard of select fruit. It possesses a large and desirable out- let for cattle and iaogs, and the farm is well adapted to grazing, which would render it acceptable to those who would prefer farming altogether. Possession can be had at any time, and payments to suit the purchaser. Messrs. GEORGE WV. PHIL- LIPS and WIc'E-a BE~vr both of Washington city, can de- scribe this farm to the satisfaction of inquiry. mar 20-w4w JONATHAN PHILLIPS. T HIS IS TO GIVE NOTICE that the subscriber hatli obtained from the Orphans' Court of Washington county, in the District of Columbia, letters of administration on the personal estate of Pearce Naddy, late of Washington coun- ty, deceased. All persons having claims against said deceas- ed are hereby warned to exhibit the same, with the vouchers thereof, to the subscriber, on or before the 14th day of October next; they miay otherwise by law be excluded from all benefit of tie said deceased's estate. Given under my hand this 14th day of October, 1836. MARY ANN NADDY, mar 16-w3w Administratrix. UCKLAND'S GEOLOGY.-Just received from S the publisher, Geology and Mineralogy, considered with reference to Natural Theology, by the Rev. William Buckland, D. D. For sale by GARRET ANDERSON, mar 15-3t Penn. Avenue, between 1lhh and 12th sts. NEW YORK INFIRMARY for Diseases of the Skin, corner of Broadway and Courtland street, (en trance No. 2 Courtland street,) open daily, fi-rom 1 till 2 o'clock Physicians.-JoHN W.ScHMDnT, Jr M.D., MINTURniPosT M. D., CHARLES A. I'POTEn, MI. D. jan 26-dt Wh1OR SALE OR RENT.-On the upperpart of Green- .A leaRs Point, the two westernmost three story Brick Houses, in which Commodore RODGEas recently resided, together with the garden, ice house, bath, smoke house, stables, carriage house, &c. &c. mar 7-tf ( ASH FOR NEGROES.-I will give the highest a cash price for likely NEGROES from 10 to 25 years of age. Myselfor agent can at all times be found at the estab- lishnmnt formerly owned by Armfiold, Pranklin & Co. at the west end of Duke street, Alexandria. - mar 14-tf GEORGE KEPHART. ASH FOR 4100 NEGROES, including bothlsexs, from twelveto twenty-five years of age. Persons having servants to dispose of will find it to their interest to give me a call, as I will give higher prices, in cash, than any other pur- chaser who is now in this market. I can at all times be found at the MECHANICS' HALL,now kept by B. 0. Sheckle, and formerly ke-t Iby Isaac Beers, on Seventh street, a few doors below Lloyd's tavern, opposite the Centre market. All cominmunicationspronptly attended to. JAMES H. BIRCH, nov 7-rit Washington City. 28. 1837. WASHINGTON CITY, MARCH 7, 1837. S EPARATE PROPOSALS will be received at the office of the Q uartermnaster of the Marine Corps, in this city, until the 2d day of April next, for furnishing, for the use of the United States, thie following articles ; 5,000 cotton shirts 2,500 linen overalls 1,500 linen jackets 3,000 pairs Germantown socks 800 fatigue caps 1,000 .blankets 4,000 pair of shoes - 500 knapsacks 600 uniform leather caps, complete, except pompons 4,000 yards ofyellow worsted lace, 3-8 inch wide 3,000 do do do 1-2 do 1,500 pompons 120 yellow worsted sergeant's epaulets 120 do. do corporal's do 1,400 do do shoulder straps 35 sergeant's sashes. Samples of the different articles can be sean at this office, and at the offices of the officers commanding marines at Portsmouth, New Hampshire ; Charlestown, Massachusetts ; Brooklyn, New York; Philadelphia, Pennsylvania; and Norfolk, Virginia. One-half of the cotton shirts, linen jackets, and linen overalls, to be delivered on or before the 1st day of May next; and the other half, together with all the articles, on or before the lstday of July tnc i it,: i..I i to be delivered at the Marine Clothing Store, in P ...l..t..p .1, good, new, and stroug.packing boxes, (for which no charge will be allowed,) without expense 'to, the: United States, and subject, after delivery, to- the inspection of the Quartermaster, or such persons as hle may appoint. The proposals to be endorsed "Proposals for Marine Clothing." E. J. WEED, tiar 8-3tawtd Quartermaster. 'The Portsmouth Gazette, New Hampshire ; American Senti- nel and Pennsylvanian, Philadelphia; the New York Times; Morning Post, Boston; the Republican Herald, Providence, R. 1.; Baltimore Republican, and Norfolk Herald, will give the above three insertions per week, and send one copy of the pa- per containing the advertisement to this office. WRITING PAPER.-W. FISCHER has been re- ceiving by the late arrivals from New York and Phila- delphia, his fall supply of Writing Paper. The assortmen is extensive, a part of which he had made expressly to order, of superior quality, and weighing from 12 to 16 ounces more in the ream than any other kind ofthe same size. 1 HIS IS TO GIVE NOTICE that the subscriber has obtained from the Orphans' Court of Washington county, in the District of Columbia, letters of administration on the personal estate of Ferdinani' F. Wood, late of Washington county, D. C. deceased. All persons having claims against the deceased are hereby warned to exhibit the same, within the vouchers thereof, to'the subscriber on or before thIe 3d day of March next; they mnay otherwise by law be excluded from all benefit ot said estate. Given under my hand this 3d day of March, 1837. mar 8-w3w MARY A. E. WOOD, Adm'x. Notice is also given, that my father, John Nowland, is here- by authorized to transact all business for me relating to the nbove administration. MARY A. E. WOOD. T HIS IS TO GIVE NOTICE that the subscriber has obtained.from the Orphans' Court of Washington county, iu the District of Columbia, letters of administration oni thie personal estate of Elizabeth Bowie, late of Washington county, deceased. All per'sois having claims against the said deceased are hereby warned to exhibit the same, with the vouchers thereof, to the subscriber, oin or before the 22d day of February next ; they may otherwise, by law, be excluded from all benefit of said estate. Given under my han'l, this 20th day of March, 1837.- HENRY MAY, mniar 21-w3w Adiinistrator. OR RENT OR SALE.-A new Brick Tavern es- tablishimnet, in thea town of Lewisburg, opposite the court-house, nine miles from the White Sulphur Sprinas, and twelve miles from the Blue Sulphur Springs, end ou the main stage line frnom Washington and Richmond to Guyan.otte, on the Ohio riyer. The heojse is 80 feet in lenghi, and 50 in width, three stories high, with thirty-one' fine sized rooms, and the kitchen in the basement story, and a large new stable, and within all other necessary ont-buildings. To any gentleman that will furnish the house, and can come well recommended, I will give one year free of rent. Letters to be addressed to DAVID S. CREIGH, or Col. THOMAS CREIGH, feb 20-3taw2rmd&c Lewisburg, Va. L AND FOR SALIE.-The subscribers will offer at public sale, to the highest bidder, for cash, on the 20th of April next, a Tract of Land named Pig Pen, containing 126 acres, more or less, and about one-half in wood. The said land adjoins Capt. C. Baden's and John Contee's lands, and formerly the plantation where the late William Cross resided, lying and being in Prince George's county, Maryland, and not more-than one and a half miles from Good Luck Post Office. It is presumed those who wish to purchase will view the land before the day of sale. Sale to take place at Good Luck Post Office, at 10 o'clock A.M. Title indisputable. . FIELDER CROSS, BEN. M. DUCKETT, feb 13-wts Executors of Col. Jos. Cross. AND FOR SALE.-I wish to sell my plantation call- ed B.oolkridge," lying in Prince George's county, Md. nearUpper iVarlboro' and Nottingham, four and a halfmiles distant from each place, containing about Four Hundred Acres, on which there is a new and comfortable dwelling-house, kitch- en, meat-house, stable, carriage-house, overseer's house, and three negro quarters, &c.; fine springs ofwater, good fruit, fire- wood in abundance, and is situated in one of the most respect able neighborhoods in tlie county. Persons hielined to purchase can view the land by applying to Mr. Grimes, the manager, and the terms made known by application to GEO. W. BISCOE, jan 28-law6w. NottinEgham. Circuit Court of tile District of" Columbla, ior tise Cottunty of Washington.-tIn Equity. George Law, vs. Charles Brugiere, James L. Duval et al. T HE bill of complaint in this ac.se alleges an agreement, between the complainant and the said Charles Brugiere, one of the defendants, by which it was stipulated that the com- plainant, in consideration of his services in and about the pro- seutien of a certain claim before the Board of Commissioners appointed under the treaty with France, providing for remune- ration to the citizens of the United States for spoliations by French subjects, &c. and in consideration of hishaving inform- ed the said Brugiere of the existence of said claim, and of his furnishing the evidence to establish the validity of the same, should have and retain out of the sum which should be awarded in liquidation of the said claim, a certain proportion thereof, to wit, one-third of tihe whole amount. The bill further shows that the complainant dlid prosecutee he said claim, and that an award in liquidation thereof was made, for$1,879, to the said
James L. David, another of the defendants, in trust for the said
Charles Brugiere : by reason whereof the said complainant
could net receive or secure any portion of the same, under the
power of attorney made to him by thie said Brugiere.
Tie complainant asserts in his bill that he ought to be per-
muitted to receive from the Treasury Department a certificate
for one-third of the amount awarded, to wit, 8626 33 ; and the
bill seeks to compel the said Duval to execute his duty as trus-
tee of the said award, and to assign and transfer to the com-
plainant his one-third part thereof; and, further, to obtain a
full discovery-.'ind disclosure, upon the oath of the said parties,
of all connexion between them in rela ion to tihe premises, &c.
&c.; and to prevent the said parties, or either of them, from
obtaining possession of the said fund, without seenuring to the
complainant what is justly'due to him, the bill prays an injunc-
tion, &e.
And forasmuch as the said Charles Brugiere and the said
James L. Duval do not reside within the jurisdiction of this
Court, but beyond and without the District of Columbia, it is
therefore ordered, this ninth day of March, in the year of our
Lord .one thousand eight hundred and thirty-seven, that the
said Charles Brugiere and James L. Duval be and appear inm
the Court here, or at the rules, in propriis persons, or by so-
licitor, on or before the first.Monday in August next, to answer
to the said bill of complaint and the several matters thereof:
or otherwise, that the said bill and the several matters thereof
be taken as confessed against the parties so failing to ap-
pear: Provided, that a copy of this order be published in tihe
National Intelligencer once a week nor three weeks, the first
publication thereof to be at least four months before said day.
W. CRANCH.
True Copy. Test: W. BRENT, Clerk.
COXE & CARLISLE, Solitinors, &c. for complainant.
mar l-w3 w
(iARRET ANDERSON has just received, fur sale,
S The German Tourist, with 17 fine engravings
A View of the 'World, as distinguished by manners, costumes
characteristics of all nations, with 80 engravings, by the Rev. J.
L. Beake.
Walker's Manly Exernisae, illustrated by engravings.
Knapp's Female Biography, containing notices of distinguish-
ed women in different nations and ages.
At his book, stationery, and fancy store, Pennsylvania Aven-
lie, between 11th and 12th streets, tab 28-3t
MONTVUE COLLEGIATE INSTITUTE
Warren county, Virginia-Post Office, Mliddle
town, Frederick county, Virginia.--This is a select school,
limited in the number of pupils, and taught by the subscriber
as Principal, with the aid of such assistants as circumstances
may require.
The most approved methods and systems are adopted; such
as are calculated to obviate useless drudgery, and to elicit the
exercise of mind. In connexion within the study of the Greek
and Latin classics, particular attention is paid to those minor
branches of English so frequently neglected.
Besides a separate English Department, and a Preparatory
Classical School,l the Institute includes four classes, embracing a
course of liberal education but little inferior to that pursued in
mostofour colleges, and at much less expense. Itis presumed
that a youth, after completing thie course of any one of these
classes, will be prepared to commence with a class of the same
name in college. As far as time and circumstances admit, the
following constitutes tire course of studies:
Cmesar, Cicero and Virgil, Arithmetic, Malte Brun's Geography,
English Grammar, Profane History, Sacred History, Elocution,
Sophomores.--Adams s Latin Grammar, Valpy's Greek
Grammar, Horace, Greek New Testament, Algebra, (Bon.)
Malte Brun's Geography, English Grammar, Profane History,
Sacred History, Elocution, Composition, Penmanship, Reading
and Orthography.
Juniores.-Adams's Latin Grammar, Valpy's Greek Gramn-
mar, Tacitus, Gr. Minoras and Majora, Geometry, (Enc.) (Leg.)
Mensuration and Surveying, (Gum.) Con. Sec. and S. Trig.
(Sim.) Profane -History, Sacred History and Ethics, Elocution%,
Conupusition, Criticism, Debating.
Seniorcs.-Adams's Latin Grammar, Valpy's Greek Gram-
mar, Cicero de Oratore, Gr. Major, Natural Philosophy and
Chemistry, Moral Philosophy, (With.) Logic (Hed.) Rhetoric,
(Blair,) Profane History, Sacred History and Ethics, Elocution,
(original,) Composition, Criticism, Debating.
In the Preparatory Classical School, such studies are pursued
as will qualify for admission to the Freshman Class. In the
English Department, parents and guardians will select the
branches desired.
A good miscellaneous library is accessible to the students at
all times, in-which are stately deposited a number of the most
approved periodicals, devoted to education, literature, and sci-
ence.
A Lyceum is in successful operation, affording opportunities
and facilities for mental exercise.
Such regulations respecting health and habits of personal
cleanliness are adopted and practised, as every parent imust-ap-i
prove. The lodging rooms are large, and constructed with spe-
cial reference to ventilation and comfort. And every practice
on the part of the student calculated to injure health is carefully
avoided.
A system of manual labor i- adopted, (altogether voluntary
with the student,) uniting healthful exercise with pecuniary re-
muneration.
The morals of the pupils are most sedulously guarded. Their
limited number and select character, as well as the retired lo-
cation of the buildings, are calculated to favor this object. All
amusements and recreautions are limited to such distances as to
avoid all contact with improper associates. The Sabbath is de-
voted to attendance on. public worship, or to such moral employ-
meats as must mineet tihe .cordial approbation of all religious de-
nominations.
The pupils are daily associated with the family circle, and
their government is purely parental. The rules and regulations
for theirdeportinent and attention'to study are enforced by them-
selves, and yet are such as to challenge the severest scrutiny
of the most rigid disciplinarian. A strict regard to truth and
personal integrity are the principles upon which they are taught
to act; and a youth whorn repeated efforts cannot induce to re-
gard these principles as most sacred and inviolable, must spee-
dily close hims connexion with the institution.
Monthly and annual examinations are statedly held, and the
results forwarded to parents in regular monthly reports and an-
nual certificates, with statements respecting progress, deport-
ment, health, accidents, &c. &c. The school is at all times
open for the ispection of fri-ends and the Public generally.
The most flattering testimonials have been received from a
very large majority of those educated in the institute, speaking
in the highest terms of the system of instruction, mode of
government, personal treatment, &c. &e. Many of these in-
dividuals are now actively engaged in professional life, and it is
presumed that they are competent to judge of the merits of the
institution.
The next session will commence April 17, 1837. It is not
desirable that the pupil visit home during the session, excepting
under very special circumstances.
Terms for boarding and tuition, $73 per session offive months. The students furnish their own lights, towels, &c. A reduction is made to pious students of limited resources, having the gospel ministry in view. No applicantreceived for less than session, or that portion of the session remaining at the time of admission. And as it is a select school, none will be admitted without satis- factory credentials of good moral character. JOHN LODOR. REFEnENCES. Winchester.-Rev. J. J. Royall, Messrs. T. A. Tidball, A. S. Tidball, E. W. Robinson, and Daniel Gold. Jeffcrson.-Rev. T. W. Simpson. Betrkeley.-Rev. L. F. Wilson. Prince William.-J. B. Ewell, Esq. Fredericksburg.-Rev. S. B. Wilson. Alexandria, D. C.-Wm. Hill, D.BD. . Fairfax.-Com. T. Ap C. Jones, U. S. N. University of Virgin.ia.-Rev. Sep. Tuston, Chaplain. mar 14-wly L AND FOR SALE.-A SMALL FARM, containing about one hundred and twenty acres, lying about three miles from Bladensburg, in Prince George's county, Mary- land, and eight' from Washington, and adjoining the lands of Mr. Stephien Onions and Walter Smith. Nearly one-half of this land is in wood; two lots have .been improved with clover, and about fifteen acres of meadow land. It has on it a good dwelling house, stable, &c., a good garden paled in,-a small orchard of excellent fruit, and fine water. The above farm will. be sold very low; and terms made known on application to the subscriber, living at Migruder's mill, in said county, about five miles from Upper Marlborough, or to Mr. William Becket, in Bladensburg. feb l--law4wcp ALARIC McGREGOR. SNDIAN TREATIES, LAWS, &c. &C.-For sale by P. TAYLOR, in one volume, all the Laws relating to Indians and Indian Affairs, by the Colonial, State, and General Governments, (including those of the Congress ofthe Confede- ration,) from 1633 to the present time, one octavo volume of 330 pages; price only$1 25.
Also, Indian Treaties and Laws and Regulations r lating to
Indian affairs, showing also the proceedings of the Old Con-
gress on tlhe same subject.; and many other important State Pa-
pers relating to Indians and Indian affairs, one octavo volume.
Speeches on tile Indian Removal Bill of 1830, one volume,
price 62j cents, containingSpeeches of Frelinghuysen, Sprague,
Robbins, Storrs, Ellsworth, Evans, Huntingdon, Everett, and
others. feb 13
PLENDID ENGLISH BOOKS.-Just imported,
S and this day opened for sale by F. TAYLOR-
Shakspeare, large foilio edition, with one 'hundred of the
largest sized engravings, splendidly bound in Turkey morocco.
SFairbai nor's Political Economy of Railroads, showing their in-
fluence upon Ihe affairs of nations ; containing also a practical
plan for converting turnpikes into railroads.
Pugin's Specimens of Gothic Architecture, in two quarto vol-
umes, filled with engravings illustrating the various styles, and
showing also the practical construction.
The Plants (by Baron Hiuholdt and M. Bonpland) of Southi
Americaand thie West India Ilands, 1 folio volume, filled witli
the largest sized engravings, splendidly colored.
Dictionary of Architecture, descriptive, topographical, and
mechanical, 3 volumes, by Stuart, Architectand Civil Engineer-
Walpole's Royal and Noble Authors, 4 volumes.
Hanoverian and Saxon Scenery, by Batty.
Te Book of the British Constitution, 1 volume octavo.
North on Fish Ponds, 1 volume quarto.
Cotman's Architectural Antiquities of Normandy, 2 folio vols.
with 100 of the largest sized engravings. I
Sir Walter Scott's Border Antiquities of England and Scot-
land, 2 quarto volumes, filled with engravings..
Graphic Illustrations and Chronological History of Architec-
ture in England, 1 quarto volume, numerous engravings.
Milner's Ecclesiastical Architecture of England during the
Middle Ages, 1 volume, with illustrations.
ThIe Court of Queen Rlizabeth, I volume quarto, very numer-
ouri authcntic likenesses.
Nichnolson's Engineerngand Architectural Dictionary, 2 quar.
to volimnes.
How to observe Geology," by De la Beche, 1 volume, en-
gravings.
Memoirs and Diary of Pepys, in the reigns of Charles the
Second and James the Second, 5 volumes octavo.
Memoirs and Diary of Evelyn, author of the Sylva," 5 vols.
oc.tavo.
Costumes, I large quarto volume, colored engravings.
**' The above works have been delayed for two months by
the closing of the Potinmc with ice, and the season for which
they were intended having nearly closed, they will be offered
for a fewdays at a much lower price than they have or can again
he sold for in Wash'ngton. mar 1
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mc~,-ra~a~l~;rx~acn~1<~~~-~i~- --r~rc~-~7mnmrrEmnca-i ~L~i~;uu~-p~iarj~a~-Ud---------Y-~-,,,,
GEOLOGY AND MINERALOGY BY BUCK-
LAND, being the last of the Bridgewater Treatises,
just published, and this day received for sale by
F. TAYLOR,
mar 15 Inmmediately east of Gadsby's Hotel.
OHN VAUGHAN, Importer of Wtines
Duff, Gordon & Co.'s Sherries
Buinnester & Brothers' Ports
Claret, Champlagne, and other Wines
All of the most approved brands, and imported direct by J. V,
up 21--d&cwly
IlOljFIIZ~5~CCIP~I~L~(C5548~.~sDF~iTL~FS
No. 7527.
UNION BANKc OF GEOnzETowWN
MARCH 2, 183i
NOTICE IS HEREBY GIVEN that .an elect
will be held, in the Banking House, on Monday, the
A pril, for the purpose of choosing twelve stockholders as ]
rectors for the year next ensuing.
mar 3-2awtd D. ENGLISH, Cashier.
r7fRUSTEES' SALE of valuable Lots of Grow
in and adjoining tile town of Cumberland.-]
virtue ofa decree of Allegany County Court, asa CourtofEqi
ty, in a cause wherein Andrew Bruce, executor of John Sco
deceased, is complainant, and Ann Scott and others defendant
the subscribers, as Trustees, will expose to public sale, at tl
tavern-house of Mr. James Black, in Cumberland, on Wedne
day, the 22d day of March next, at II o'clock A. M. several v.
luable Lots and parcels of Land in and adjoining the town .
Cumberland, embracing all the real estate of the late John Scot
The greater part of the above lots front on the road leading I
Hagerstown, opposite -Mrs. Slicer's tavern, and are advantage(
ously situated for building lots.
Lot No. 195 fronts on Mechanic street 66 feet, and runs bad
to Wills's creek, and adjoins the lot on which the tavern-hous,
stafids, now kept by Mrs. Edwards.
The whole of the above lots will. be. sold clear of dower, Mrs
Scott having assented to the decree.
The- terms ofsale are : One-fourth of the purchase money t<
be paid on the day of sale, or on the ratification thereof, and th<
balance in three equal annual payments, with interest from the
day of sale, to be secured by bonds with such surelies as the
subscribers may at proveof. On the payment of the whole ol
the purchase money, the Trustees are authorized to execute
deeds conveying the property sold, free, clear, and discharged
of all the parties to this cause. WILLIAM PglCE,
ANDREW BRUCE,
jan 10-wtds Trustees.
''ILMINGTON CLASSICAL INSTITUTE,
WV Quaker Hill.-The course of instruction in this In-
stitution, now in successful operation, embraces the Latin, Greek,
and Hebrew languages, Mathematics, and .the usual branches of
a substantial English education. Number of pupils limited to
thirty. TERMS.
For the Classics, with strict attention tothe English branches
in which the pupils may be found defective, 81io0 per annum,
For the English branches, Mathematics, and Natural Sciences,
$140 per annum, payable as above. This coves all expenses, board, tuition,'washing, fuel, lights, &c. Books furnished by the pupils. References to thefollowing gentlemen rons of the Insti- tation. DovER. Hon. J. M. Clayton, U.S. i WILMINGTON. Hon. Arnold Naudain, U. S. Senator J. J. Milligan, Representative to C tigress. NEW CASTLE. Rev. J. Decker, J. Cooper, M. I). I-Ion. R. Black, f Superior Court. Kensey Johns, jr.Chancellor. Dr. Colesberry. SALEM, (New Jersey.) Rev. A. Heherton, J. Vanmeter, M. D. Col. R. Johnson. I?HILADELPHIA,. Rev. Ashbel Green, D. D. Paul Beck, Esq. " Wtn. Young, Esq. BALTIMORE. IH. Niles, Esiq; Editor of the Register. John Robinson, Esq. H. B. Pennington, Esq. RREV. S. M. GALEY, jan 3-2aw3m Wilnmington. F AND EPO)R SALE. -By virtue of the last will and -A testament of Joshua Jcies, late of Frederick county, de- ceased, thie subscriber offers at private sale the entire real es- tate of tliedeceased, consisting of the home farm "Traveller's- Rest," containing 301 acres. This farm lies on tlie road lead. ing from Liberty Town to Baltimore, six miles from Liberty Town and thirty miles from Baltimore, half a mile distant from Sam's creek,and within ofie mile of Jacob Landis's, Paul Man- ren's, and Levi Devilbiss' mill. Thei quality of this land.is equal to any in the neighborhood, and so well arranged that the stuck may have free access to water from any part of the farm. About 76 acres are in woodland, of healthy, thriving timber, and'convenient for every farninig purpose. The buildings con- sistofa two story brick house, 40 by 30 feet, with six fine rooms, cellars,&c. The whole is thoroughly finished in a neat, comfortable manner, and well calculated for a genteel family. Attached to the dwelling is a comfortable log kitchen. Tihe barn is built of logs, partly weather-boarded, with two threshing doors, and stable room for horses, cows, &c. Thern is a finer apple and peach orchard, and a variety of fruit; also, a well of excellent water at the door. The neighborhood is healthy, and moral and respectable in every point of view. Also, a tract of land of 30 acres, adjoining the lands of Cas- par and Thomas Devilbiss, and half a mile distant from Jacob Landis's mill ; part of this tract is- fine meadow land, and the balance under cultivation. The improvements consist of a comfortable log dwelling and stable, with a never failing spring at the door. Also, a tract of 67j acres, adjoining the lands of Dr. J. L. Warfield and Thomas WAorthington ; 20 acres of which are cleared, and the balance in fine thrifty woodland, part of which is yonng growing chestnut. It is deemed unnecessary to say more of these tracts of land, us persons wishing to purchase can view the premises by calling on the familyat the home place, and for the terms, which are moderate, on the subscriber, residing in Union Town, Freder- ick county, Md. JOSIIUA J6NES, Acting Executor. an 14-lawts K ENTUCKY LAND AGENCY.-The undersign-. ed having succeeded to the office of Surveyor of Military Lands in the State of Kentucky, west of the Tennessee river, has facilities for superintending those lands as Agent for distant proprietors, aund lie tenders his services to pay taxes, to sell, or to do any other act in regard to those lands, which their owners may wish performed. He states, for ties information of those at a distance, that speculators are endeavoring to appropriate those lands to themselves, in virtue of Kentucky land warrants, and that there is a necessity of attending immediately to the military claims. Letters addressed to him (postage paid) at Columbus, Hickman county, Kentucky, will receive attention. feb 4-wlOw FRANCIS T. TAYLOR. STATIONERY.-F. TAYLOR has just received (in ad- -dition to his former large supply of very superior Station- er , 40 gross English Metallic Pens, warranted of superiorquality, and selected with that object, withoutregard toprice, beingPer ry s, Heely's, Gillot's, arind Windle's celebrated Pensofvarious descriptions ; also several new kinds that have not been seen in Washington. Terry's London Writing Ink, Black, Red, and Japan. French Writing Ink, Red and Black, London Ink Powder. Also on hand 4 varieties Red and Black Ink of the best Amne- rican manufacture. English and Holland Quills, number 60, 70, and 80, Yellow, White, and Opaque. Brookrman and Langdon's London Drawing Pencils, warrant- 'd genuine. , Also nI hand Jackson's, Monroe's and Cohen's American manufactured Pencils of every number and letter. English and French Wafers, English, Irish, and Vienna Seal- ng W ax. . Also on hand several varieties ofthe best American Wax.' 4 English Pounce, German Red Tape, French Silk Taste, In- lia Rubber, (London patent.) English Letter Paper, Blue andt White, Luid and Wove, Plain ind.Gilt. English and French Note Paper. . Foolscap and Letter Paper on hand from the manufactories of Butler, Hudson, Donaldson, Gilpin, Ancs, and others. *** Public officers anti others may depend on having the ,, bove articles supplied at as low prices havingg regard to the |nality) as they can be procured anywhere in the United States. he subscriber also offers, with the same guaranty, a large" tock of Stationery, and Stationery Articles, (not enumerated above ) of American as well as foreign mneanufacture, the quality nd finish of which has been looked into with the greatest care nd attention. mar 20 F. TAYLOR. -*-S *. .^ .. ", >* CONGRESSIONAL REPORTS. FROM THE COMMITTEE ON THE ADMINISTRATION OF THE EXECUTIVE DEPARTMENTS. HOUSE (tL REPRESENTATIVES, MARCit 3, 1837. REPORT OF MR. WISE-CONCLUDED. Notwithstanding the principles of the majority as illus- trated by thile foregoing resolutions and votes, as toI sPEci- rfic and definite investigation, the very first question pro- pounded- by them, in committee was so vague and indefi- ite, so intangible and abstract, that one of the most intel- irent and.respectable witnesses first called, tlhc Hon. James Palrker, of New Jersey, who did know of a specific act of he worst corruption and abuse in one or the other, or both he President and Secretary of the Treasury, could not an- wer it onil account of its general form. (" First question by Mr. Mann to Mr. Parker: "Do you, ofyour own knowledge, know of any act bIv either fthe heads o! tile Executive Departments which is either cor- upt or a violation oftheir official duties ? "Mr. Parker presented the following objcclions to answering: I do not understand this quest n sufficiently to enable mie answer it in this general form. I came liere by order of the oummilttec, neither as accusernor to accuse ; and I consider iny- elf boun I to answer questions on those points only to which my attention is directed by the committee. "Mr. Pearce moved that thie objection of Mr. Parker to an- 'werinog Ihe question be overruled, and that Ire be required to answer tihe same. -"Mr. Miann, upon the suggestion of Mr. Wise, withdrew Ihis question, to enable Mr. WYise to examine Mr. Pa. ker as to tihe pecifricacts; and Mr. 'earee accordingly withdrew Iris motionn" But that question was repeatedly put to other witnesses itih the obnoxious view of proving NEo.IrnvELY a general ood character of the Administration, or of making certain witnesses purge themselves of certain charges against that haractcr. Mot only was this, general question propound- .d, but when Messrs. White, Pcyton, and Pickens were ,ailed, Mr. Mann stated tire reasons in writing for calling .hem-his specifications of reasons were : 1. That tire purpose for which ie has desired the honorable witnesses, named in the said resolution, to be sworn is, to prose- ute the inquiries di-ected by the resolution of thie I'House of representatives ofthe 17th of January instant. 2. Thie matters to which they are expected to testily are, cts, ifany ihey know respectively, of their own knowledge, whichh will show a wilfil violation ol the duties of the heads of e respective Executive Departmentsn f the Government of te United States, or tire subordinate officers connected with .eil Departments, or either of them. "3. The 'charges against theE xecrtive Departmnrts,' which is expected they will sustain by facts within their own know- dge, are corrupt violations of official duties. "Tihe question being stared, whetl;er, in the foregoing speci- cations, Mr. Mann has complied with the requisition o'f the re- .ii;... .. :.. i:. the samne and whether tire witnesses pre- r h :, ill -..? "',I ; those who voted infi tle allirmative were : Ayes-Mr. Pearce, Mr. Mann, Mr. Clhaney-3. Those who voted in tire negative ere : Nays-Mr. Wi-e, Mr. Muhlenberg, Mr. Campbell, Mr. arks, Mr. Lincoln-5. So it was decided that said specification does rnot comply "ith ihe requisition of tihe re-slutiun. ''" The honorable Francis W. Pickens, a reemrerrofthe House, minroned as a witness, read to the comiiittee a paper, which denominated a protest, against his being examined as a wit- ess ; and which, when ie should be called upon to be sworn, 3 said lie would submit to be placed upon their files. "tMr. Mlann sulnitled, iun compliance wilthi Ithe requisition of ie last meeting, for specifieatiors as to the grounds ofsummon- 'g tire witness in attendance, the following, viz. 'ccoud specifications by 11r. ]lMann. Mr. Mann, in compliance with thie conditions of tihe resolu- mns of tis committee of thie 2Sth inst. states, in writing, agari: 1. That tie specific purposes for which he lihas desired the 3norable witnesses inained in thie sid resolution to be summon- 1, are to prosecuted tile inquiries specifiedM ad directed by tihe solution of tile House of Representatires of the 17th January slant. 2. Th' matters to which they are expected to testify are, Its within their own knowledge, if any they know, severally, their own knowledge, concerning the condittion of the various xecutive Departments; lshe ability and integrity with which ey have been conducted ; the manner in which lthie public busi- 'ss lihas been conducted i n all ofthirem ; the failure of such De- rtnents to accomplish the objects oftheir creation ; there viola- n of tihe official duties of thie said Departmseuts respectively. "3. The charges against thie Executive Departiients, whiichl is expected they will sustain by facts within their own know- Ige, are -charges of corrUtipt violations ofnfficial duties, abuses tihe administration of the public affairs, with which such De- .rtmerats are charged by law and tire Constitution. "And the question being, Is the assignment ofreasons for rnmonring said witnesses sufficient, and in compliance with the solutions of lire committeeT' it was decided in s le affirmative, foliows:-s Ayes-Mr. Campbell, Mr. Hannegan, Mr. Mann, Mr. Cia- !y, and Mr. I\ ise-5. - Nays-Mr. Mihlleriberg and Mr. Parks- 2. Such it a specimen of the sPECtIFIC examination of a ember of the Senate and members of thie House, who had !en called at the request of the President to purge them- Ives of all contempt to his Administration 1 When another class of witnesses was called, some from a Departments, others frorn a great distance, to testify of ts of corruption and abuse, as notorious in this metropo-. as the noon-tide sun, acts named and specified before a coinmittec until reiteration became tiresome, thie nma- ity became inmore strict and contracted in the inves- :ation. Question by Mr. Wise to Mr..Buck : 1.' I'L Do you know tire amount of patronage of tie War De- 'tment to the press, and the principle upon which printers are ected to do the public printing; whether they are selected on .omit of their political opinions? '" Tis question was objected to by Mr. Parks ; and on the 2stion being put, Shrall thie question be propounded 2 it was eided in the negative, as follows : Ayes-Mr. Catripbell, Mr. Lincoln, Mr. Wise-3. Nays- MAr. Pearce, Mr. Mulilenberg, Mir. Hannegan, Mr. n, Mr. Parks, Mr. Clianey-6. Question by Mr. Wise to Mr. Buck : '15l. Do you know, or are you inftrored, whether any of tire ds ofDepartments, or any officer or agent thereof; has been, s now, interested in Indian reservations'? Answer by Mr. Burck I do nuot know, neither have I been wrined, that any one of tlte heads of Departments is now, or r has been, interested in Indian reservations neither do I )w that any officer oil agent of either Department ias ever i, or is now, so interested. " Question by Mr. Wise to Mr. Buck : 16. Do you know, or are you informed, whether any of the ds of the Executive Departments, or any officer or agent eof has been interested in the purchase ot public lauds' V 1'his question was objected to by Mr. Parks ; and thie lies- being put, Shall the interrogatory he propoundedd! it was ided in thIe affirmative, as follows : Ayes-Mr. Wise, Mr. Muhlenberg, Mr. Campbell, Mr.Lin- t, Mr. Hannegan-5. Nays-Mr. Pearce, Mr.Parks, Mr. Chaney, Mr. Mann-4. Answer to question 16 by Mr. Buck : I have no knowledge te facts mentioned in tie above iuterrogatory : neither have ,y information in relation to the same, except such as is de- d from the newspapers of thIe day. Question by Mr. Wise to Mr. Buck : Do you know iupo what principle public officers are ap- !ted to and lereoved.'froi office, in the "several Executive ,artnents ; whether appointments and removals are not made guardd to the political opinions of officers ? This question was objected to by Mr. Pearce ; and on the ition being-taken, Shall the interrogaitry be propounded 'I it decided in the negative, as ibllows e yes-Mr. Campbell, Mr. Lincoln, Mr. Wise-3. ays-Mr. Pearce, Mr. Muhlenberg, Mr.-Hannegar, Mr. \to, Mr. Mann, Mr. Clianey--6. W. J. Duane (late Secretary of the Treasury) appeared as toss. Mr. Wise submitted the following question to be proposed idd witness, viz. 1:,. Will y'ou please to state tll that you know respecting the luct ofthc President of the United States in removing the ie money from the Bank of thIe United States, in tire year The question being objected to by Mr. Mann, and tile rues- stated, Shiall said interrogatory be propounded?, it was de- ' d in tlhe negative, as follows : Ayes-Mr. Muhlenberg, Mr. Campbell, Mr. Lincoln, Mr. a-I. Nays-Mr.Pearce, Mr.tlanne.gan, Mr.Parkl, Mr.Manrn-4. Mr. Wise thIen submitted the following question to be pro- tded to the witness, viz. 2. Do you know whether the Presielent consulted or advi- fith Reuben M. Whitney or Arms Kendall as to that merta- ,'and wliatiufluence those persons had upon the President king that step? Objected to by Mr. Mann ; and the question-being stated, I said intearogatory be proptnodedt? it was decided in the tire, as follows : Ayes-Mr. Campbell, Mr. Lincoln, Mr. Wise-3; Nays-Mr. Pearce, Mr. Muhllenberg, Mr. HIannegan, Mr. s, Mr. Mann-5. VIr- Wise also submitted the following to be propounded to witness: i. Have yon reason to believe that your official relations to government were disturbed by the active interference of Vhiitney and Kendall, or either of them, with the opinions ! President in relation to tlhat measure ?e )bjected to by Mr. Mftrer; and tie question being stated, said interrogatory be prolounded? it was decided in the. doe a hololows : Lyes-Mr. Campbell, Mr. Lincoln, Mr. Wise-3. 4ays-Mr. Pearce, Mr. launnegan, Mr. Parks, Mr. Mann, tuiihinberg-5. n" Qu,.tion by Mr. Wie lo tMr. WV:dbUnry : 2. Will yonu please firn'ish this committee with a cnpy or copies of the papers in the Treasury De, artment,.or in your possession, particularly thie report of Mr. Littlefield, the colrect- "or, in relation to the removal of David Melvill from ithe office of weigher and gauger at Newport, Rhode Islard ? Objected to by Mr. Mann ; and on thIe question beingstated, Shall said interrogatory be propounded ? it wa decided in tihe negative, as hollowsr: Ayes3-Mr. Mahilenberg, Mr. C.nampbell, Mr. Lincoln, Mr. WVise-4. Nays-Mr. Pearce, Mr. Hannegon, Mr-. Mann, Mr. Parks, Mr. Chancy--5. Question ry Mr. Wise to Mr. WWoodbury :. 3. Please state ill thiaT you know in relation to the removal ofDavid Melvill fi-omin the office of weigher and gaugerat New- port, Ilthode Island, and the reasons fur said removal. Objected to by Mr. Mann ; and thie question being stated, Shall the interrogatory be propounded ? it was decided in trhe negative, as follows Ayes--Mr. Campbell, Mr. Lincoln, ;'lr. Wise-3. . Nays-Mr. Pearce,-Mr. Muhlen'.crg, Mr. IHannegan, Mr. Parks Mr. Mann, Mr. Chancy-6. Question by Mr. Wise to Mr. \VWoodbury .3. Are ithe papers witichi you did not communicate to tine Senate, because they are connfidential, on ihe files ofthIe Trea- sury Department ; and was tine report of thei collector, Littl'e- field, included in tihe number oftpapers considered confidential Objected to by Mr. Mann ; and on the question, Shall said interrogatory be propounded ? it was decided in tlre negative, as follows ;' - Ayes-Mr. Ciampbhell, Mr. Lincoln, iMr. Wis,-3. Nays-Mr. Pearce, Mr. Parks, Mr. Mann, MIr.GChaney, iMr. itbhlehberg-5. Mr. Wise proposed thie following question, to be propound- ed to thie Hron. Aaron Vanderpoel, oftltie House, a witness pre- sent, via. 1. Did yont inform any melnber or meminibers of thie Hoise of Representatives that the President. desired ot preferred that the resoluti(rn, which was adopted on thel 17th of Janiiary, under which this committee is appointed, should be passed ; and, ifso, by what authority did you give such information '. Objected to ITy Mr. Parks; and on the question beingstated, Shall said interrogatory be propounded 7 it was decided ir tllie negative, as follows: Ay-Mr. WVise-I. "Nays--Mr. Muhlilenberg, Mr.Campbell, Mr. Hannegan, Mir. Parks, lMr. Lincoln, tMr. Mana, Mr. Clhaney-7. Mr. Wise proposed thre following question, to be propound- ed to Mr. Vanderpoel, viz. 2. Did tine President-of the United States .informyou, orlinti- 'mate to you,, or to anry one else in your knowledge, that lie de- sired that tire resolution of the 17th of January under -which this committee was appointed, should be passed by'the House . Si" bjected to by Mr. Maan ; and on-the question beingstated, Shah said interrogatory bie ,ropounded? it vwas de'ded in the negative, as fbllows: Ayes-fMr. Campbell, Mr. Wise-2. "Nays--Mr. Pearce,t Mr. bMulenberg, iMr. Hannegaa, Mr. Parks, Mr. Lincoln, Mr. Mann, Mr. Chaney-7. Honorable James Standtfer, of the House of Representa- tives, being present, Mr. Vise proposed the following question : Question by tir. 'Wise to Mr. Standefer: 1. Please state all that you kinow respecting a letter that was written, some time during the year 1334,1o Benijamin F.Cur- ry, Ihen acting ais agent of tihe Government, in treating with the Cherokee Indians, by the President of the United States, re- spectingyourself; whether said letter was not used publicly, by said Curry, against your election to Congress; and whether lie was trot influenced by the President in electioneering against you as a candidate? andstate thie purport of said letter, as exhi- bited toyou asnd tocrowds in your district. Objected to by Mr. Parks, and rejected by the following Tore : Ayes-Mr. Campbell, Mr. Wise-2. Nays-Mr. Pearce, Mr. Park s, Mitr. Lincoln,.Mr. Mann,hMr. Chaney-5. Question by Mr. Lincoln to Mr. Standefer: 2. Did Benjaini F. Curry, an Indian agent, in tine last congressional canvass in your district, publicly exhibit a letter which he represented-to be addressed to him by the Presicld'nt of the United States, to prejudice your claims to favorable consi- deraltion as a candidate in the election 'i, Objected to by Mr. Mann, and rejected as follows : Ayes-Mr. Lincoln, Mr. Wise-2. Nays-Mr. Parks.-, Mr. Mann Mr. Chancy-3. Question by iMr. Wise to Mr. Towns : 2. D o You kn ow, of your own knirwledge, or from any of the officers 6r agents of 'lie Executive branch of this Government, whether they, or either of them, are now, or have been, inter- ested personally in purchasing or speculating in the reservations of Creek or other Indians ; andl, ifecitherfof tIem, who? "Objected to by Mr. Mann, and rejected by the following voteI Ay-Mr. Wise-J. Nays-Mr. Mul.!eiiberg, Mr. Parks, Mri. Mann, Mr. Clia- ney-4. "Question by Mr. Wise to Mr. Tnvns-. 3. Do you know, or have you beeu iniflormed by him, swbeth- er trle Hion. John Porsythi, Secretary of State, is now, or has been, personally interested in purchasing or speculatling in the reservations of fl-. i..'.. t.., thelr Indias'. QObj:ecied to Ia, '. ',,.in., and rejected by the following vote: "Ayes-Mr. tMuhlenlberg, Mr. Wise-2. "Nays-Mr. Parks, Mr. Mlann, Mr. Chaney-3. n Question by Mr. Wise to Mir. Towns.: "4. Do you know, of your own knowledge, or from informa- tLion derived from either of them, whether Jolihn -J. Abert, whIilst agent of tire Gervernment to locate thie. reservations under the treaty of 1832, with Ihe C(reek Indians, was personally inter- ested and engaged in purchasing and speculating in said reser- varionus ; and, if so, whether John F'orsytlh, Secretary of State, was interested, in like manner, with said Abert, or others ? Objected to by Mr. Mann, and rejected by the billowing vote, thie committee being equally divided . "Ayes-Mrl. Muhilenberg, Mr. Campbell, Mr. Wise-3. "Nays-Mr. Parks, Mr. Alann, Mr. Chaney-3. 5Questiou by Mr. Mann to Mr. 'Towns : "5. Do you know, of your own knowledge, or by information derived from him, whether J. J. Abert, whiilst agent of thie Go- vernment to locate the reservations under the treaty of 1832, with the Greek Indians, was personally interested aind engaged in purchasing such reservations ? "Answer by Mr. Towns: "I do not know, of my own knowledge, or front information derived from J. J. Abert, or any other source, that he was per- sonally interested and engaged, in purchasing Indian reserva- tions under the treaty of 1832, with the Creek lndians. "Question by-Mr. WVise to Mr. Lewis: "4. Was there not a contract entered into by J. and L. Jo- seph & Co. of New York, and R. J. Phillips, of Philadelphia, on the one part, and William D. Lewis and others, on the other part, early in the month of November, 1S35, or about that time, to operate in tile purchase of slock in the Morris Canal and Banking Company, the latter parties agreeing to furnnish fruds to a large amount; and were not the funds drawn froniom the Gi- rard Bantik, ind furnished monthlyfrom November to April suc- ceeding, inclusive ; and was not tine account closed in June, 1836, by paying over to you (William D. Lewis, and others) your share of the profit; if so, how many thousand dollars ; and was not Reuben MA. VWhitney, agent of the Gilrerd Bank to trans- act its business with thie Treasury Department, concerned with you and others in said speculation and profits? Objected to by Mr. Pearce, and rejected by time following vote : "Ayes-Mr. CampbclI, Mr. Lincoln, Mr. Wise-3. Nay--Mr. Pearce, Mr. Muhlenberg, Mr. Hannegan, Mr.' Parks, Mr. Mann, Mir. Cltanrey-6. Question by Mr. Wise to Mr. Lew's : "5. Had you not a correspondence with Reuben M. Whit- ney, in the autnnn of 1835, in relation to a speculation in Mor- ris Canal and B3anking Company stock, and w:th reference to Iris procuring a portion of the public revenue to be placed in said bank for tIre purpose of enhmanting the value of its stbek, to favor your profits and his; and~lid not Mr. Whitney give you reason to believe that ha could so procure a portion of the public revenue fr the purpose aforesaid 2 Objected to by Mr. Mann, and rejected by the following vote , otAyes-lMr. Carmpbell, tir. Lincoln, Mr. WVise-3. "Nays-Mr. Pearce, Mr. Parks, Mr. Mann, Mr. Hannegan -4. Noother question was propounded. "'Question by Mr. Wise to Mr. Hobbibi : "Do you know, of your knowledge, or fronm the ioinfamation derived from them, whether any ofiicees or agents of thi rrea- sury Department, or of any other Execritive Department, since the 4th of March, 1829, have been interested or concerned in purchasing or speculating in the public lands? if so, state all that you know or are inforaoed of, by the officers or agents them- selves, Os to their purchases arid speculations aforesaid. "Objected no by Mr. Harnegan, and rejected by the follow- lng vote: "Ayes-eMr. Muhlenberg, Mr. Caminbell, Mr. Lincoln, Mr. WVise-4. "Nays-Mr. Peatnc, tiMr. Hannegan, Mr. Parks, Mr.. Mant , t'Il. Chancy-5. Question by Mr. Wise to Mtl. Hobie : 6. Please state all that you know respecting the removal of B. H. Wheeler from tine office of postmasler at Providence, Rhode Islhnd. Objected to by Mr. Maui, and rejected by the followiuig vote : . "Ayvs-tMr. Mnhlenberg, Mr. Lincoln, Mr. -Wise-3. "Naysti-Ml. Pearce, Me. Csmpbell, Mr. Parks, Mr. Manu, tleh. Chaney-5. Question be Alr. Wise to Mr. Ilnbbie : S y7. Do yutiknow whether ai postmaster in one Of the New England States did, Or did inot, write to tiePost Office Department thut It'ho wished to remove some distance, say twVenty or thirty miles froimn his office, but. wished to retain his office as postmaster, saying lie would have tlie duties of thel etoffice discharged by a cleric, and that lie could still assist to re-elect General Jackson ; and dtid you yourself not writc a letter in' reply, that he was at libertv to do as lie request-c ini[ ir-- ;. i iiin to do all tie cou'd to electioneer lor G. .- i i. i .... Objected to by Mr. Marimt, and rejected as follows: "Ayes--Mr. Munhlenberg, Mr. Lincolin, Mr. Wise, Mr. Camp- bell-4. Nays--Mr. Pearce,tMr. Parks, Mr. Mann, Mr. Chaney-.l. Queiitioni .y Mi:. Wibie to Mr. Friylh : "3. Did youi, or not, exert )your influence, personal or official, witi allny Senator or other person, to have the treaty ratified with said stimulation a s to tire Golphin claim; or with any per- son, an officer or agent, or not, of the Government, to have said stipulation inserted in said treaty'? Objected to by Mir. Parks, and rejected by thie following vote; . Ayes-Mr. Campbell, Mr. Lincoln, iMr. Chancy, Mr. Wise --,l. Nays-iMr. Pearce, Mr. MuhleAnberg, Mr. Parks, Mr. Mann-4. "Qunestion by Mr. wise to Mr. Forsythi : 4. Did you note whilsit Governor of the State of Georgia, re- commend the Golphin claim to the favorable consideration of thie Georgia Legislature'? Objected to by Mr. Parks, and rejected by tlre following vote "Ay-IMr. Wise. iNays-Mr. .Pearce, Mr. Mndilenberg, Mr. Campbelli, Mr. Parks, Mr. Lincoln, Mr. Mann, Mr. Chaney-7. Question by Mr. Wise to Mr. Forsyth : "6. 1Have you, or not, been directly or indirectly interested or councerne4 in tie purchase of, and in speculating in, the rer- servations of Creek or oeiliter Indians, since you have. been in the office ofSeretasy of Stale? Objerted to by Mir. Mann, and rejected by tlie following ,ate - Ayes-tMr. Mti'irenberg, Mr. Lincroln, Mr. WVise-3. "Nays-Mr. Pearce, Mri. Campbell, iMr. Parks, Mr. Mann, Mr. Cianey-5. Question by-Mr. Wise to iMr. Pearce : SWill you pleas- o stale all that you know respecting tihe causes, reasons, and influences, whiich were brought to bear, or operai'ted on the collector, Mr. Litlefield, at Newport, Rhode Island: or upon the Secretary of thie Treasurye in removing David iMelv ill,t a weigher and ganger under said collector, from the said oaliee of weigher and ganger ? S iObjected to by lMr. Parks, and rejected as fillovs, Mir. Pearcr being excused from voting : "Ayes-Mr. Campabell, Mr. Lincoln, Mr. Wise-3. "Nays-Mr. Mulllenberg, Mr. Parks, Mr. Mann, iMr. Cha- ney-4. Question by Mr. Wise to Mr.KendaH : "2. Do you. 6now whether tIhe President of ithe United States" dild or did not communicate to you and ioRenben M. Whitney his intention to remove the deposits befoIre he advised with the Secretary of the Treasury ; and whether lie did not approve of R. AI. Whitney as contemplated agent t of the dteposte banks to be selected before their selection ? "Objected to by Mr. Maun, and rejected as follows,: Ayes-Mr. Camrpbell, iMr. Wise-2. "Nays-Mr. Pearce, Mir. Muhlenberg, Mr. Parks, Mr. Mann, Mr. Chaney-5. Question by Mr. Wise to Mr. Kendlall: "4. Please state to this committee all you know .--"' : the formation of i] club called the Hickory Club, c "-" i. officers of thie Governmentt in this city ; state its organization, its design, and its means of operation ; whether its members were officers and agents of rime Executive Depattric nts ; by v% hom it was organized ; whether its design was to influence thie elections of tine People ; 'and whether its means were de- rived, or not, in part from tie salaries of Executive officers? Objected to by lMr. Parks, and rejected as follows: "Ayes-Mr. Campbell, iMr. Wise-2. p,: Nays-Mr. Pearce, lAr. Muhlenberg, irl. Hannegami, Mr. Ptrks, Mr. Lincoln, Mir. Mann, Mire. Chaney-7. Question by irl. W-ise to Mr. Kendall: i"Do you know whether any officers or agents of the Execu- tive Departments trave ever formed political combinations to control the elections of thie People, and to influence the public press? Objected to by Mr. Miann, and adopted as follows: Ayes-.-Mr. Pearce, Mr. Muhlenberg, Mri. Campbell, Mr. Lincoln, Mr. Wise-5. Nays-AMr. Hannegan, IMr. Parks, Mr. Mann, Mr. ChIa- ncy-4. "Answer by iMr. Kendall "I have no knowledge-of any combinations of public officers for thIe objects stated in tihe lustion, nol; of any combinations of which public officers fin ruedt part, hfr tany other purpose than to promote objects of a general character, by discussion of prin- ciples, without regard to men. "Question by AMr. Vise in tMr. Kendlil : 6. Will you please to state what combinations you know of to promote objects of a general character, of whiichi public offi- cers formed a part; the character of those combinations; whe- ther. they were political or not ; whether favorable or not to this Administration, and to thie election of Marltin Van Buren to the Presidency; and whether they aimed a procure tie Govern- ment patronage for i.. ;, i.' ? 1t Objected to by 1Mi-v r 1 and rejected as follows: Ayes-AMr. Campbell, Mr. Lincoln,i Mr. Wise-3. Nays-Mri. Mufleriberg, iMr. Hannqgan, Mr. Parks, :'Mr. Mann, Mr. Chaney-5. Question by Mr. Wise to tMr. Kendall: 8. Will you please look upon the paper handed you, and state what you know respecting tihe facts therein spoken of? "ThIe paper alluded to is in the following words, viz. o",Sory of the Indian reservations. "Somte years ago, certain tracts of land, situated principally or wholly in the State of Mississippi, were reserved 'by Con- grcss (or by Indian treaty, to which Congress assentcd),lfor Ithe use of tlihe Indians, and to be disposed of by then, and for their benefit, whenever the President of thIe .United States should give his assent to such sale and transfer, (not otherwise.) These lands were known to be very valuable, and the poor Indians could be easily enough managed ; perhaps they hIad, or were about to leave the, east fr thie west side of the Nississippi river; but how to obtain thie assent of tihe President to so large a Esale of Indian lands to a company of'speculators, seemed a more dif- ficult matter. A company was formed in Boston two or three years ago, with, it. is believed, a capital of$300,000, to try to
effect this object. Amos Binney, Esq. was a leading man in
the company ; and it is believed that Brodhead, navy agent in
Boston, was another; and various otherindividuals had a greater
or less interest in it; but what didn, nas is believed, obtain the
President's assent to tile sale and transfer, was the admission of
Amos Kendall, at present Postmaster General, intothe concern;
he to have one-third part of the profits of the speculation when
it shall be closed up, without, in Fact, paying one dollar of the
consideration, although lie may appear to have paid his part as
well as all the others. Yet ithe agreement of the other pa tners
with Mr. Kendall was, that they would furnish thie money to
pay his one-third part of the consideration, free from interest,
provided he (Kendall) would oblain the. assent of the President
to tihe sale, and would, ushen requested so to do by the other
partners, go to the lands and transact such matters and things
relating to their common interest as the company might deem
expedient. The mindss were purchased by the company; there-
fore, we atire to infer that Mr. Kendall did obtain the President's
assent to the sale ; but Mr. Kendall wias not, and probably will
not, be Called oni for any further 'services. Those interested in
the purchase, speak confidently oftheir expectation of realizing,
at tihe end of tihe sales, three or finir dollars for every one inves-
ted. The People of the United States, by this transaction, have
not been defrauded or overreached ; but the interest of the In-
dians in those reservations his probably been obtained by this
company lfr less than half its market value. How far the Pre-
sident should guard thle interest of the. Indians, is for him and
Congress to determine; possibly it may have some connexion
with Ihis oath ofoffice. But if tihe interests of thie Indians must
or may be sacrificed, shall it be done fbr thie benefit of a few
favorites, and at the sole suggestion of oneo individual, himself
moree deeply interested than tiny other l February 9, 1837.
Objected to by Mr. Mann, and rejected as fellows :
"Ayes-Mr. Campbell, Mr. Lincoln, Mr. Wise-3.
Nays-Mr. Hannoegan, Mir. Muhlcnberg, Mr. Pearce, Mr.
Parks, Mr. Mann, Mr. Chianey-6.
Question by Mr. Wise to Mr. Kendtall;
Have you, or not, since you have been Fourth Auditor and
Postmaster, General, or since you bave been an Executive olli-
cer of this Goveruanent, beer editor, proprietor, or part otnmr,
or publisher, joint or sole, of a newspaper called the Globe, or
other newspaper published in- this District, or in the-United
States? If so, state whether you have or have not written edi-
torial articles for the same ; and whether you have had or ex.-
cised a control or riot over its general course in politics.
Objected to by Mr. Hanaegan, mnd rejected as follows :
"Ayes-Mr. Campbell, Mr. Lincoln, Mr. Wise-3.
"Nays--Mr. Muhlenberg, Mr. Haunegan, Mr. Parks, Mr.
Mannn, Mr. Chaney- 5.
No further questions were proptonded to the witness.
Question by Mr. Wise to Mr. Ilittlfield :
1. Please state to inis committee all that yon kiow respect-
ing thIe cordndut of David Mtlvill, whilst in tine office of weigh-
er amid gauger, at Newport, Rhode Island, and respecting his
removal from thiat office, and the action of tIme Secretary of thIe
Treasury thereon.
Objected to by Mr. Pearce, and rejected by tIne following
vote ;
Ayes--Mr. Mnhlenberg, Mr. 'iWise-2.
"Nays--Mr. Pearce, Mr. Parks, Mr. Manu-n3.
Question- by Mr. ',Wise to Mr. ]Ienshaw :
" 1. Is Amos Kendall mow, me tims lie been sincee InhasIbeen
an Executive officer, a member of any company for the purchase
of the public lards? If so, state what company, and tlie extent
of his interest.
Objected to by AIr. tibent, and rejected :
Ayes-Mr. Gampbell, Mr. Lincora Mr. Wise-B3.
Nays-tMr. Pearce, Mr. Marne, Mr. Chaney'-3.
'" Question by Mr. Wise to Mr. Henshraw :
"2. Did thie said Amos Kendall apply to become a member
of said company, or was he applied to by said company, or any
of its members, to become a arlenuber?
Ohujeeted to try Mr. Pearce, and rejected :
"Ayes-Mr. Caropbeall, tie. Lincoln, Mr. Wise-3.
Nays-tMr. Pearce, Mr. Mann,, Mr. Chancy--3.
Question try Mr. Wise to Mr. Henslhaw :
"3. Did time said Amos Kendall make iny advance to the
capital stock of said company' And, if so, in what manner was
the sum procurcd and advanced ?
SOljeeted to by Mr. Manrn, and rejected:
Ayes-Mr. Campbell, Mr. Lincoln, Mr. t Vise-3.
Nays-Mr. Pearce, Mr. Mann, Mr. Chancy-3.
i Question by MrI. Wiss to Mr. Ilenthaw :
"4. What adVeilntage or benefit was contrinpulted from the
said Amos Kendall hos..in,. *.icnsie)meoer of said coitpany '
Olbjelcd to by '. I'. and rejected:
Ayes-Mi-. Cinmpbell, Mr. Lincoln, Mr. Wise--3.
: Nays-Mr. Pearce, Mr. Mann Mr. Chaney-3.
Question by Mr. "Wite to Mr. Hitnrlaw :
"5. Did said Amos Kendall at any time, and, if so, wheiu, ap-
ply to be released from said company ? Anid, ifeso, what reasons
did Ihe-assign therefor? .
Objected to by Mr. Mlann, and rejected :
"Ayes-Mr. Campbell, Mr. Lincoln, Mr. Wise-3.
Nays-Mr. Pearce, Mr. Marn, Mr. Chaney-3.
"Question by Mr. Wise to Mr. Henshaw :
"9. Have you any information ofpersons interested witih Mr.
Kendall in tire profits of buying arid selling public lands ? If so,
state what.
I ihave no information of any persons interested, att this time,
within Mr. Keudali in tihe profits of buying and selling public
lands.
Question by Mr. Wise to Mr. lensihaw :
10. Have you any information of persons who have been in-
terested with Mr. Kendall, since he has been an Executive ofli-
cer, in tile profits of buying and selling public lands? Ifso, state
what.
Objected to by Mr. Parks, arid rejected as follows :
"Ayes-Mr. Muhlenberg; Mr. Wice-2.
"Navs-Mr. Hannegan, Mr. Parks, Mr. Mann, Mr. Cha-
ney-4.f,
In this exhibit of catechism we see neither cpnuistency,
nor propriety, nor liberality, nor fairness, in propounding
or rejecting interrogatorics. Some questions are propound-
ed to some witnesses, which, in substance the sarne, are
rejected as to others. Subjects of inquiry of thie deepest
interest to tho Public were peremptorily excluded from in-
vestigation. Mr. Woodbury, for example, was not per-
mitted to respond as to thie removal of David Melvill, or
to explain why it was that hie could communicate one pa-
per and withhold another from Congress, touching the
same matter, because done was confidential, the other not.
Mr. Duane had been called before one committee of inves-
because it acas too full for the limited resolution under
which that cormmittce was appointed; hlie was called before
this committee to testify as to the grossest abuses on the
part of the President in recognizing arid consulting with
unknown and irresponsible private persons, of doubtful
character, to the exclusion of those who were Iis regular
cabinet ,counsellors and constitutional advisers, and the
majority would not permit him to testify at all, BECAUSE tHE
HAD BEEN CALLED BEFORE TiE OTHERS COMMITTEE. WHIrCH
HAD ALSO REFUSED TO ALLOW tHIM OR ANY OTHER WITNESS
TO TESTIFY AT ALL ON THE SUBJECT OF ABUSES. Mr. Van-
derpoel, of New York, was called to testify whether hle had
not, as was known to a member of the committee, repre-
sented THAT THE PRESIDENT DEaIRED THE RESOLUTION OF
THE 17th JANUARY, UNDER WHICH THIS COMMITTEE WAS AP-
POINTED, TO PASS, AND NOT THE AMENDMENT REQUIRING
SPECtFIC CHARGES, which was offered by the gentleman
from Rhode Island ; and to testify, also, as to what autho-
rity he had for making this representation to members ; aind
the majority refused to hear himn. Mr. Standefer was call-
ed, as stated to the committee, to prove that the President
of the United States had written letters to Benjamin F.
Curry, an Indian Agent, which letters were used, arid in-
tended to be used, by that subordinate executive officer,
publicly, against the election to Congress of Mr. Stande-
ler; that triese letters were read publicly by this agent to
crowds of the people in Mr. Standefer's district, in Ten-
nessee; that there was strong circumstantial evidence to
prove that this was done with the knowledge and approba-
tion of the President; and yet the majority would not ex-
amine this witness, because the conduct of the Presidentrcas
not involved in the inquiry under lthc resolution, asit was al-
leged he was not an officer or7 agent of the Executive De-
partmnents.
And the witness, Littlefield, was sent for hundreds of
miles for tile known object of telling all hlie knew in rela-
tion to the removal of Davidl Melvill, at considerable ex-
pense and trouble; and when he arrived ho was permitted
to testify only as to some stale charges against that in-
jured man, supported only by ex part proof, taken with-
out notice to him, and trumped up long since Ilis removal
for the obvious purpose of punishing him for daring'to
complain of wrongs already inflicted. Although there are
highly penal laws of the United States against any class
of executive officers being concerned in trade, or in the
purchase qf public lands, or other public property, (see
Gordon's Digest, page 30,) and althougis the charge was
purchasing public lands, and other public property, were,
anrid had been, constantly speculating on their official influ-
encc; and although'there is the most obvious impropriety
and incompatibility in any head of any department being
thus tempted and tempting in his .place, yet thie subjects of
dealing and speculating int Indian reservations, wherein
there is much foul fraud daily practised on tribes of unpro-
tected savages, whom thie United States arc bound to pro-
tect, and on this Govern ment itself, and whence have, no
doubt, sprung such disastrous wars;i and of dealing and
speculating in public lands, whence, it is supposed, has
been generated so much corruption arid bribery aniong the
officers of the Government of every description, antid pri-
vate citizens of all classes, wrve sealed subjects in this
committee.
The majority, too, it is proper to state, showed as little
INDUSTRY as zeal in prosecuting the investigations of tIhe
committee. They generally voted to adjourn to the latest
day ; they could not be got to meet more than once a day:
a resolution was passed to meet at 10 o'clock A. M. and 7
P. M.; one night session was held on the 16th "February,
another attempted on the 7th; but two members (Mr.
LINCOLN and Mr. WisE) attended, and the resolution to
meet twice in twenty-four hours was repealed before it
operated twice; Such has been, in general, the course of
-the committee. Such wpas to have been expected to be its
course from tile moment of its appointment. "Six friends
of the Executive to three of the Opposition were placed
upon it by the Speaker, who is supposed to owe his elec-
tion to the influence of the President over a HIouso where
there is anrt overwhelming majority in favor of the Admin-
istration ; and ofthese six, several were known, by their
speeches on the floor, to-be utterly opposed to the resolu-
tion under which the committee was appointed, and to the
investigation which that resolution instituted.
But the appointments and labors of the committee have
not been in vain. Though their inquiry has had to con-
tend with the power and popularity of the President-with
thIe majority which his name and influence held in the
House-with his official machinery there-with thie com-
mittee created to smother its efforts-with all unprecedent-
ed resistance to its powers by tire Departments-with one
ofthe worst evils of the times, that gag-law with which
patronage rules the silence of the best witnesses-with the
heaviest masses and burdens of papers, with which- any
bureau usually covers up calls for information, and baffles
all altcmpts at analysis or synopsis, except when at partial
concealment or a labored self-acquittal is meant-wilh
shortness of time, six weeks, in which to examine tihe
most momentous and voluminous subjects, the witnesses
scattered hundreds and thousands of miles over the United
States, during the winter season-and though the House
discharged from attendance the main witness of all, as to
one of thie most serious charges against a Department, and
tlihe committee lihas since refused to cause him (R. M.
Whitney) to be summoned under a resolution stating the
strongest special reason for taking his testimony, (see
journal, page -,) yet, in spite of every obstacle, the inves-
tigation has-developed many and important facts which it
becomes cvcry'man in tlIe nation to know.
It is the duty of the undersigned, also, to present the
facts of another transaction, which involves thIe conduct of
the Secretary of State. Reference iJ made to the fiacts
simply, without comment or the expression of an opi-
uion. A treaty, or pretended treaty, was concluded at
New Echota, Georgia. on the 39th day of December, 1835,
by Gen. William Carroll and John F. Scherrmerbmorn, on
the part of the United States, and the chiefs, headmen,
and people, as was said, of the Cherokce tribe of Indians.
Whilst the commissioners of the United States were act-
ing, application was made to them to insert an article in
that treaty binding this Government to pay a claim, com-
- only called thac OLPHIN CtrAI. A synopsis of that claim
is herewith presented in the form of the following letter to
thei commissioners:
"Hon. Wtm.Carroll and the Ieon. John F. Sdcermerhorn:
"GENTLEMEN: Thie Cherokee Indians having, in a late
treaty c'omnluded by you as courmissioners of the United States
appointed for that purpose, expressed their wish that certain
traders might be paid lislir just debts, whiichl were stipulated to
be paid by the treaty of 1773, I have taker tIre liberty of laying
before your a short history of then, being mooe loll titan here-
tofore communicated to you.
FProm the year 1761, till the date of tine treaty, in 17-63,
these traders lind finished the ordinary supplies to tIre In-
dians, on thie fhith und credit of the Creek and Cherokee ua-
tions ; that, being in great distress and poverty, tire Indians
impltt ed the British crown to accept of a cessiou of their land,
(now Wilkes county, in tinc State of Georgia,) to the end that
their trader"- ni _- t be pad Idmbeir debts, and enabled to furnish
Ihem (the I.'.I.,. ,1 with goods as usual. Aecordir gld r iu De-
cember, 1772, the Colonial Governor of Georgia was in-
structed to hold a treaty in compliance with ice wishes of
the Indians, by which instructions it appirsat lhat thi British
crown IWas not to be pledged, ol any account, fIr the payment
of those debts, but lthat ihe lia ds intended to be ceded were
to ble sold, and the proceeds aipptlied, in tlie first place, to the
extlguInishnietnt of those debts, and the surplus appropriated to
thie defence of thio colony.
"l The treaty wasi niadc in 1773, and contains but a single ob.-
ligation on tfihc part of the British Government, which was Tihe
payment of thie debts due to thie Indilun traders lni 1m tie sale of
thie ceded lands.
At the date of the treaty, tile Indian traders not only releas- tihe subject with Mr. Preston, of South Carolina, Mr. Brown, a
ed tire British Government,m but also the Indians, from all liabili- North Carolina, and Messrs. King and Cuthbert, of Georgia,
ty on account of the debts of the latter, and perhaps with others ; but to noone without a distinct uaru-
Thie Colonial Gnovemrnment of Georgia, acting in obedience ing that I spoke in the character of counsel for the parties, hav-
to instructions, appointed a commission to execute the treaty, by ing a contingent interest. My appeals to them were founded
selling tihe lands comprehended in the treaty, and ascertaining solely on time justice of thIe claim, and the hardship of the condi-
the amount that was respectively due to thie Indian traders when L tion of the claimants."
thie war of thie Revolution broke mut. The following communication was received and read :
"Before, however, this eventhappened, on the 2d May, 1775, ;" jA r 0o February 14, 1837;
George Golphin, who was an Indian trader, and held by as- SIaR: I ask leave of the committee to correct an error in my
signment the plains of other Indian traders, obtained a liquids- I statement relative to thIe amount of the Golphin claim. By re-
tion of his claims to the amount of.9,791 I5s. 5d. of thie cur- Perring to document No.83, of the Senate, you will find a copy
rency of thie then province ef Georgia ; which sum was again of the certificate; and the amount is 9,791 15s. Sd., and not
guarantied to be p according to the stipulation of tie treaty. 9,000, as I had supposed yesterday.
TiThe effectofthe. revolutionary war swas to place beyond thie 'I am, sir, your obedient servant,
power of- tie Britishi Government thIe perbfrmance of the treaty "JOHN FORSYTH.
by the means therein specified. lButa part of these traders, whoi Hon. HENRY A. 'WISE,
were loyal to thie erown during that contest, were afterwards /Chair'man ofthe Commnittee, 4-c. cf-'c."
paid by the British Government, notwithstanding the release
heretofore refl'erred to. Afterwards, John Ross, the principal chief of the Che-
Pending the negotiation at Paris, in 1783, a memorial teas rokec nation, was called, and testified as follows:
laid before the Amernican commissioners, in behalf of certain AMr. Wise to Mr. Ross:
merchants trading to South Carolina and Georgia, asking farin- '1. Please state asl that you kaow respecting the means
demrnification fior debts due to thiemu from ithe Creek and Clero- which were employed, or tie influence exerted ty any Oicer
kee Indians, for the payment of which a tract of land was ceded or a e E e >r e D nlene y n ip i
or agent of the Executive De'partnents, to have the stipulalion
In Georgia in 1i773. respecting the'Golphin dlaim, commonly so called, inserted in
As the American commissioners had no authority to admit the last treaty with the Clherokiee natio; and to ohaltain your as-
or deny thIe justice of thie claims, they were transmitted to Con- sent to the sami, after it was inserted, as a chief of that nation
greess. or e ie.
"'It is believed that Congress never acted on this subject ; "2.i ereyo ffeed reard, bribe, oraluable consider-
or, if it did, suhl action was adversely to the claims of the me- ationofan kind-if so, what -by y offic or agent of either
morialists ; for we find that, in July, 1768, an act of Ithe Bri- ofny the Exective Departmenti, or by any personie or;: agent of eticer
tish Parliament was passed creating a commission to inquire orae the Eectif eptments, or by any peron fo : eany officer
into the claims of sufferers by the cession of Georgia to trIe oe agent thereof if by any oner, uhon .-to obtain youre assent,
Americans. that of any other ihadman or chief of your nation, to said
Ameridtanos.tGolpint claim, or to said treaty, in whlicr it was insertedoi
And iu 1790, the sum of .749,536, with, interest at the rate 3.Will you please state. all that you know respecting the
of four per centum, was appropriated for the payment of claims .ondc 'ite yo p P oesecraer all tia you knot' espengs tohe
on la.rids in Georgia ceded to lle Americans. ducdt oftire 'arious officers, agents, superintendents, or other
on ands in Geogia ceded to ira Anterian. s persons employed or paid by the Government to superintend
Under the expectation of being indemnified by these acts and negotiate its affairs with the Cherokees. from rime year 1828
of Parliament, tihe representative of George Golphin employed u1p to tie present period ?
Charles Goodwin, Esq. a distinguished lawyer of South Caro-
lina, now deceased, to go to London and receive the amount of "Answer ofSir. John Ross, Indian Chief.
his ancestor's just debt, under these acts of Parliament. The WASHINGn oNo CaTY, FnB. 25, 1837.
mission of Mr. Goodwin resulted in a failure, not on account of S Sin In reply to the first question propounded to me ly the
the justice of the debts of Golphin, but the obnoxiousness ofhis honorable committee, I have thn e honor to state that I know of
conduct during thie revohtfionary struggle, none of the means which were. employed, or of the influence
On this side of the Atlantic, thie exertions of those interest- exerted, by any of tire officers or agentsof the Executive De-
,cd in these claims have been equally unsuccessful. It did partments, to have thie stipulation respecting thIe Golphin claim
seem equitable that .when Georgia had acquired jurisdiction (so called) inserted in the (alleged) Chrerokee treaty. 'That in-
over the ceded territory in question, she ought to have paid these strument was negotiated and entered into with certain ounn-
debts. Acting, probably, under this conviction, this State, in theorized individuals of the Cherokee nation, ata time when I
1780, passed ama act requiring such Indian traders who were 'ias in this city sitha a delegation who were duly authorized
friendly to the independence of the colonies, cnd hml claims on amid empowered try said nation to negotiate a treaty sith the
the Indians, for the payment of which the county of WVilkes was United States Government. Aftdr the arrival of Joh n F. Scher-
ceded, that they lay them before the then, or some future Le- muerhorn, the cennmissionser of the United States, in this city,
gislature ; and whatever was found to be due was to be paid in rand of several of the Cherokee individuals who had entered
Treasury certificates, payable in two, three, and four-years, into the aforesaid instrument, tumd nwhoead comen for the pur-
bearing interest at six per centutn. pose of getting their proceedings ratified by the Goverenment,
"Holding forth, as this act did, a pledge that this debt ofGol- the duly authorized delegation, of whihl I teas a member, re-
phin, and all such like, would be paid, his representatives liave ceived front there Ciherokee people, thi ough the h ands ofeerta il
agsin and again petitionend tine legislarenre of Georgia The special messengers, their protest against the ratification of the
uniform course of that Legislhturemhas been to receive the peth- pretended treaty aforesaid, and which was comnnicated to
tions, raise a committee, whso report favorably, and then lay. it tile War Department for the information of tiea President. At
on the table for the balance' of the session. None ever ques- tine same time, the delegation stated their readiness to negotiate
tinned the justice of the debt, or the firm and devoted attach- swith the Government for m treaty, by which the Cherokee diffi-
meat of George Golphin to the liberties of hIis country, cuties might be satisfactorily and honorably adjusted. A reply
However unfaithfully the State of Georgia may seem to have was returned through the Comrnissioner of Indian Affairs, ery-
acted on this subject, her conduct will he probably justified by ing to us, (tile delegation,) You will distinctly understand that
these considerations; lshe did not, by her own individual act, you will not be recognise,I by the.Department as members of
defeat there fulfilnment of thie treaty of 1773,but that it was defeat- s delegation, unless you will unite ith those who had conic o
ad by the act of the United States, as it was a war of all the with the treaty, and sign the same, and o-operate wi ththem to
States united. effect its ratification.'
"And more especially that, as the State of Georgia, as arly r "To the second question I have tIhe honor to state that no
us 1783, had set aparl lfor thle soldiery and other troops this reward, brile, or valuable eonsideatiou of any kind, has been
same territory of Wilkes county, (being then her only valuable offered me, by any officer or agent of either of the Executive
and uulocated lands to which the Indian title wias then extin- Departments, or mby any person, for anry officer or agent thereof,
guished,) for the purpose of fulfilling her engagements to tthe to obtain my assent, or thtat ofany other headman or chiufofmy
contineutul troops. nation, to said Golplmin elaim, or to said instrument in which it
That afterwards, in 1784, when her territory was enlarged was inserted.
by the addition of two othlier counties, a large section ofherafer- From the nature of the oath which hlas been adnmtinistered
tile lands -was reserved, for the space of 'twelve months, 'for, t nme, and tire generality of the questions propounded, I feel
the officer's, seanen, and soldiers who were entitled to landis bound futlher to state, as concisely and substantially as my mre-
in that State by asy resoloe of Congress, or act or resolve of m'ory will permit, such facts known to tme as I believe have any
that State.' bearing upon those questions.- Some timelduring the session of
S" That, still finding the bounties promnisedl to thie continental the Congress of 1832-'33 I was called rupon in ny room at
soldiers could not be located by reason of the smallness of Ithe Brown's hotel, on one Sunday'morning, by a person who intro-
territory above referred to, Georgia afterwards, min 1785, declar- duced himself as a Mr. Hunter, door-keeper of the House of
ed that another portion of her soil should be deemed a reserve Representatives, and who inquired if I was acquainted with
fur the space of twelve months, 'to make good her engagements Mr. Barney McKinny, of Augusta, Georgia. I replied in ti e
to the continental soldiery, and seamen, and officers ofthre me-. affirmative. He then asked if I knew any thing about lthe Gol-
dical departmentt' pbin claim? I replied that Mr. MeKinny, to whom he had just
"ThIns we find tlat, before the termination of the revolution alluded, had once been at rmy house in the Cherokee nation,
ary war, the State of Georgia had actually bestowed, as a re- and was accompanied by Colonel Andrew Erwsin ; that said
source of carrying on that war, on thie continental soldiery, by McKinny had laid before ime certain papers in reference to that
way of bounty, this same territory, which had been pledged, by claim ; that lie considered the claim to be a good one against
thie Colonial Government, for the payment of debts due to tire the State of Georgia; and that he had proffered to lease the
Indian traders ; and, still finding her engagemuents to that sol- Cherokee gold mines, and to pay the nation in thatclaim ; that
diery unfulfilled she continued to grant-bounties out other soil. my reply was, that I lhad no authority to dispose of the gold
In this aspect of tie case, it does appel that, whatever liabili- mines in any manner, nor did I know whether the general
ty appears to rest, in tile first place, on tile State of Georgia, council oftihe nation would be disposed to rent them out; and
that liability really and equitably rests upon the United States. if the council would inake a lease of thenm, I was sure that it -
More than half a century has" been passed in earnest and would not agree toacceptofthat claim in payment, howevergood
finuitless negotiation with every power capable of doing justice it may be against Georgia ; because, if that State had proved
to these claims. The Indians, in the last resort, have been ap- herself faithless towards the just rights of her own citizens, by
plied to; they have only heard the simple history of these withholding payment to that claim, the Cherokees could have
claims, and acknowledged thie moral obligation that they ought no confidence that she would be more faithful towards them in
to be paid; that, as a matter of future security, and to avoid, paying it, when transferred to them. tMr. Hunter remarked
hencoeforth, all importunity on this subject, when about crossing that he haind acted as an agent for'the proprietors of that claim,
the Mississippi, and abandoning the lands of their fathers, they in trying to have it recognized and paid, and that he mad spent
desire that their fathers' debts may be paid. a good deal of money on that business ; so Ire was interested in
"MILLEDGE GOLPHIN, said claim. That he had heard it was probable that the Chero-
SOne of the heirs of George Golphin." kee delegation, then in the city. won-d nterit r ,;nt in t to,
An article was inserted (the 20th) embracing the claim,
to wit:
"Art. 20. The United States do also hereby guaranty the
payment of all unpaid just claims upon the Indians, without ex-
pense to them, out of the proper funds of the United States, fir
the settlement of which a session or cessions of land hias 6r
have been heretofore made by the Indians in Georgia : Provi-
ded, Tihe United States, or the State of Georgia, has derived
benefit from thie said cession or cessions of land, without having
.made payment to tie Indians therefore. It isI hereby, however,
further agreed and understood, that if the Senate of the United
pairing any other provision of this treaty, or affecting tIhe In-
dians in any manner whatever."
The treaty was sent by the President to the Senate with
that article in it. The Senate, May 16, 1836, refused to
advise and consent to the ratification of that article, by a
vote of 26 to 12. What caused the Senate to reject it thus
decidedly is not known, except what appears on its face,
that it singularly enough stipulated with the Indians that
the United States would pay its own or Georgia's debts out
of thie proper funds of the United States.
February 13th, the H-on. John Forsyth was called before
this committee, and the following examination of him as a
witness took place:
(I Question by Mr. Wise to Mr. Forsyth
1. Were you, or riot, personally interested in d certain
claim, commonly called time Golphin claim, as to which a stipur-
lation was inserted in the last Cherokee treaty, as sent to tire
Senate of the United States to be ratified?
"I have been interested in the Golphin claim since 1S27 or
1828, as counsel for tIle representatives of Golphin, and expect,
whenever it is paid, a portion of thie sums recovered.
"Question by Mr. Wise to Mr. Forsyih :
"2. Do you know w.hiiether any person or persons, connected
or not with tine State Department, or interested or not in- said
Golpin claim, offered a reward in" money, goods, or other valu-
able consideration, to a Cherokee chic!, named Jolhn Ross, to
assent to the stipulation as to said claim irinserted in said treaty I
Answerby Mlr. Foasyth : I do not.
Question by Mr. Mann to Mr. Forsyth :
9. Has tine Golphin claim, in any manner, been officially
before your Department for examination, pending the negotia-
thion of the late treaty with dtie Cherohiee Indianss?
"Objected to by Mr. Parks, and adopted as follows:
Ayes-Mr. Pearce, Mr. Muhlenberg, Mr. Campbell, Mlr.
Lincoln, Mr. Mann, Mr. Wise-6.
t Nays-Mr. Parks, Mr. Chancy-2.
"Thie Department of State, since it has been un.icr-amy care,
has had no concern with tihe Golphin claim, other than in certi-
fying some documents among thie files of papers relating to a
time anterior to thie adoption of tihe Federal Constitution. All
the business of Indian treaties is transacted in the War Depart-
ment, to which during the administration of it by Mlajor Eaton,
I delivered a statement of the Golphiin claim, with an view to
have it provided for by some subsequent arrangement with the
Creek or Clherikee Indians. Thanstatement having been mis-
laid, another statement was substituted for it, by the parties in-
terested, during Governor Cass's administration. While tihe
treaty was negotiated here, the representatives of Golphin had
ar agent (Judge Underwood) in this cily, who applied to me to
urge tho President to admit thie claim, whlichi Underwood said
ine Indians wished to see. paid. I declined any conversation
with thie President on thie subject, because of my contingent in-
terest. Governor Cass told' me he thought thie claim just, but
doubted whether it should not be paid by Georgia, nd not the
United States. The President, as Governor Cass informed nie,
refused, on that ground, to permit ar article respecting it tio be
put into thire treaty. And when the treaty was considered and
decided utipon inlltie Cherokee country, time agents of Golphin
procured from theni thIe article as it went to thIe Senate. Tlhe
claim was not admitted to form part of the treaty, but it was be-
fore tire Senate on its own merits. Tirho original demand was
,000ooo. A law of Georgia promises to pay 6 per cent. interest.
I had no further counnexion with the insertion of thie article in
tim treaty, otherwise than advising the representatives ol Gol-
plin, before inserting it, to procure from tihe Indians an urgent
application for tihe payment of thie claim; and all the conversa-
tions I had on lmthat subject, prior to the treaty, were winh r lip
parties interested, or thie ir iattornecys. 1 applied to Major Eaton
and Governor Cass to examine rlie claim, andil feu'nicled inmeans
of forming a just opinion. Both were informed of nmy personal
interest, and thlatl what I said to them proceeded front tiat inter-
est. Vhiileo the treaty was before the Senate, I conversed on
cession with the Government; and if, in case a treaty be nego-
tiated, and I would get an article inserted in the treaty for tIhe
payment of that claim, he would make me interested in it to the
amount of $40,000 or$50,000; this proposition was spurned,
and the interview broken off. -Some short time thereafter, I
was again visited in my room by another gentleman, who intro-
duced himself to me as a Mr. Crawford, of Augusta, Georgia,
then late Attorney General of that State. This gentleman re-
marked that hie was interested in the Golphin claim, and, from
what hlie had heard ofMr. Hunter's interview with me in refer-
ence to that claimnl he was sorry to believe that Mr. Hunter had
presented the subject before meinamanner that was offensive; ,
and he lihoped, from the knowledge I had ef his character, and
the respect which he entertained for mine, that I would believe
him incapable of proposing any thIing that would be dishonor-
able. I related what had passed between Mr. Hunter and my-
self, and expressed my regret and disapprobation of being thus
tampered within. He expressed his disapprobation also of the
manner in wvhichl Mr. Hunter had presented the subject before
me. Mr. Crawford then proposed to surrender into my hands
the documents relating to the Golplinclaim ; and:said, ifatreaty
be entered into with the Goernment, and the delegation would
get an article inserted to. bind the United States to pay that
claim, the delegation m might retain such a portion oftime amount
of the claim, for tihe benefit of their nation, as they thought pro.
per-even the one half, so that the residue be paid over to the
proper claimants. I refused having any thing to do with the
claim, or to examine the documents, because it was not a debt
against the Cherokee nation ; and if considered as a claim
against tie United States, it ought lo be presented before the
proper officers of the Gover .men, fobr settlement. Some tinie
during the sess-ion ofthe Congress of1834-'35, mW illiam H. Un-
derwood, Esq., of Georgia, vlho had been employed to defend
thie rights, ofthe Cherokees before tlie courts of that State, ar-
rived in this city, unsolicited by thIe Cherokee delegation, and
whilst thie delegation were in correspondence with tle Seen etary
of WVar on the subject of negotiating a rei'aty. AIr. Underwood
remarked to me that lie was intrusted with tihe Golphin claim,
and was promised a handsome fee for its collection ; that ie'
was poort, and if the delegation negotiated a treaty with
the Government,i he would take it as a great favor in me if I
would secure thIe insertion of such an article in it, whicIh he
would draw up, couched in sich language as would not, in ltihe
slightest manner, afTcrt the interests or rights of the Chero-
kees, but which would commit the United States to pay the
claim, and that I should be no loser. I replied, that lie well
knew I had every disposition to render him any favor, without
remuneration, when in my power to do it honorably, and with-
out injury to tille nation. A short period thereafter, when I was
preparing a communication to thIe Secretary of War, emnrbracing
certain propositions for a treaty, iMr. Underwood came into mv
room, and showed me an article which lie had drawn up, to
embrace thIe Golphinh claim, and asked if I would not, in the
concluding part of the communication which I was then writ-
ing, insert it as a part of the propositions of the delegation. I
replied, no: and hie retired romn thie room. Soon after this,
Mr. John F. Schermerhorn, a commissioner of thIe United
States, negotiated a proposition in treaty form with John Ridge
and other individuals of the Cherokee nation, then in this city;
and when Mr. Underwood left the city, it was made known to
me that thIe Government had paid his expenses in corning, stay-
ing here, and returning home.
thie spring of 1835, it was communicated to me that Mr. Under-
wood and John Ridget had written i letter to the Secretary of
Wari, suggesting that, if thIe Cherokees were assured that Ithe
President would not offer them atny other sterns for a treaty thIan
were contained in tIhe prepositions negotiated with Ridge and
others, in all probability they would be induced to adopt them ;
that a letter, in reply from thie Secretary, was returned, making
sno. declarations as had been tsuggestetd, extracts of which were
then transmitted by Mr. Underwood to certain persons in the
nation, for lie information of then Cherokees. After thIis, there "
followed a letter from thie President of lthe United States to
Governor L.umpkin, authorizing tie Governor to make it
known, fori thIe information of the Cheroklces, that, if they did
not i.ccept of ihe propositions offered, he would iot, during his
administration, offer them arny other terms, but give them up to
the jurisdiction of thIe State atulthmoritins, to be dealt within as they
may think proper. In thIe course of rthIe summnner of thiat year,'"
Major William Y. ihmnsoll, who had leen associated with Mr.
Underwood as an attnrney-lt-law, paid me a visit at a mineral
spring, where I had taken my family for ltIeir health. Ile
minade known to me that Mr. Forsyti, the Secretary of State of
tie United States, was then or had c been in Georgia, and that
ie (tansell) hIad asccerlninped from an unquestionable source
that Mr. Forsyth was one of the parties interested in the Gol-
phin claim ; that ie possessed great influence over thne Presi-
dlent, and, notwithstanding the declarations made by the Presi-
- j* 0.' 0
glh Governor Lumpkin, M.'. Forsyth could tand would
President to grant an additional suit of money sui-
ver the Golphin claim, over and above what was stl-
the propositions submitted to time nation, if the Che-
uld sanictin a treaty upon such terms.
3d question, I beg leave to remark that a statement
stion would necessarily be very lengthy, wlich, toge-
the want of references to such documentary facets as
present within my reach, renders it impossible for
'pare an answer during the present session of Con-
!ie honorable committee will therefore please to ex-
br simply referring Ithem to the correspondence be-
self ad associates and t various officers of the Go-
and to the memorials and protests submitted both to
ive Dl)epartmenti and the Congress of the United
myself and colleagues, on ithe part of the Cherokee
in 1828 up to the present session of Congress; and,
ioin, to lay before them ar official general order, (No,
d Head Quarters, Army, E. T. and C. N., Fort
'ciber 3, 1836,' and signed 'John E. Wool, Briga-
'ral commanding.'
have tine hoor 1to be, very respectfully,
"JOHN RO-3S.
e Hon. HSznry A. WIsE,
3hmirnian of tle Select Committee of Investigation.
HEAD QUARTERs, AvMY, E. T. and C. N'.
FORT CASS, Nov. 3, 1836.
GENERAL ORDER-No. 74.
instructed by the President of the United States,
the War Department, to make known to Mr. John
all others whom it may concern, that it is his deter-
to have the late treaty, entered into between the
plates and the Cherokee people, and ratified by the Sc-
25th May, 1836, 'religiously fulfilled in all its parts,
i conditions, within the period prescribed ;' and that
gati6nl which may be ent' to Washington, 'with a
obtain new terms, or a modification of those of the ex-
Mly, will be received or recognized ; nor will any in-
i be had with them, directly or indirectly, orally or in
and that thle President regards the proceedings of
and his associates, in the late Council held at Red
s in direct contravention of the plighted faith of their
and a repetition of then will lie considered as indica-
design to prevent the execution of the treaty, even at
rd of actual hoslitiles : and they will be promptly re-
further made known, by instructions from the WarDe-
t, that 'if anty of our citizens enter thie Cherokee coun-
incite opposition to tihe execution of the treaty,' they
roceeded against according to the laws of the State, if
t ou the subject, in which they may enter; and, if there
a no law of thu, State which can be brought to bear on0
id under which they may be removed,' it is the opinion
'resident,' as expressed through the War Department, -
my may be removed' out of the country under the 6th
,f thle treaty,' in which the United States guaranty that
rokees shall be protected against interruption and in-
'rain citizens of the United States who may attempt to
the country,' unless it is with the express consent of
mite iwho are acting under tie 12th article of the trea-
,by the terms of that article, they alone are authorized
officers of ithe army, whether commanding volunteers
.ar troops, under my command, are required and direct-
ake knosvn to all persons resiitng, or who may come
lie range of their respective commands, the contents of
er; and to make diligent search and inquiry in regard to
ens who may enter the Chcrokee country and invite up-
i or interfere with the due execution of the treaty, and
.heir names and places of residence, without delay, to
head-quarters, in order that they may be proceeded
according t thie laws of the country and thle instruc-
'the President of the United States. They are also re-
mitd directed to prevent all meetings, and to break up all
s coming- to their knowledge, assembled in the Cherokee
-, or the purpose opposing the treaty, ordiscussing its
section.
"JOHN E. WOOL, "
amount of this Golphin claim, principal andi inter-
estimated at about $150,000. undersigned deems it to be his duty to present also r subject clearly before the House and the nation. the 11th July, 1836, the Treasury Department issued ilar to the land receivers and deposit banks, requir- ecie in payment for the public lands. This circular, tlie'ed, was dictated by the President, without the rrence of the Secretary of the Treasury ; it is be- Ito have benefited speculators in the public lands nany of whom are charged to be officers of the Gov- nt; and the circular itself was thought to be, if not' action of law, a suspension of law-at least in viola- : a sacred principle of civil liberty that all power gof :ding lawis, or the execution of laws, by any author- thost the consent of the Representatives of the Peo- injfrious to their rights, and ought not to be excr- The circular was an abuse in itself, but its appli- ,or rather the exception in its application, was a r abuse still, an the following correspondence between ranch Bank of Alabama, at Decatur, and the Secre- 7 the Treasury, will show. cashier of the Branch of the Bank of the State of -na, at Decatur, addressed a letter to the Secretary of treasury, dated July 28, 1836, in whichi-he says: -CH Or' THE BANK OF THE STATE OF ALABAMA, DECATUR, JULY 28, 1836. i: In easequence of yourletter, under date of the 11th amlressed to the receivers of public money," [&c. :r r- -irctular requiring specie for the public lands,] S-- ..f this institution have ordered me to make the ag inquiry : easequence of the purchase by you of five hnndred Tml dollars of Alabama Sater bonds, being for the increase ca pial! of this branch bank, the payment of which, has :: .-, r I- .1-- trom time to time, by the receiver of r'>r.'-' -r '1r- Iaads sold, or tobe sold, for the ben- the Chiekasaw nation, as folly expressed in the terms of s. sil .l, nuner date 31 aDfrchi, 16836,1 would, there- cay ree-peafsclty beg leare to inquire whetheryoa will lie li vs, wi er the said receiver at Ponfiloci to accept, in pay- inr s isl public land-s, the notes, or certificates of deposit, S ineatc bank, to thie amount of$31jC00, or such ani
it as may be due this branch bank at the time of said pay-
bintag made. This bank, as a rlater ofcourse, agreeing
elaIS its own notes by checks'at sight-iin this instance,
e eiier at the U(nionBank ef L',tiianaor Citizenis Bantik,
"Means; the Mechaniec' (Bank, Philadelphia, or the Phie-
ski, NIew York; for any sunm or sutfs over and above thle
al de o it from the Treasury, and which might be paid to
s-serat Poatitoc for Chickasaw lands during the present
lik te~ae-st is notl made with a view to thie accommodation
l t k i swa k s l'eh as for theo ctnuenienee of thIe People, par-
li tt&i.--' -'i i-. .1 r .' ,- .:.1 whom hays al-
i o tsei ... .i : ii '" '. .' ,.. :. Ian ,, and are con-
misva h o remove there. lI it, therefore, at their sug-
ai ilsai-se dre "ory effthe institution hove been induced to
',awi-u ap;psictio to &P mrilde; for (pemit me to say)
,auotmI elia is fully prepared to afsbrd its crinsners the
i ,r -i,' .i. i- .r ilie puuymentif their lands in specie dol-
and risk in thetransmission of tbch being
I oiwkl satlaileldgedl to be great, through'a country but
,w*i'- ed-, a,' where several robberies and depredations
Owati ematel, sthat we are anxious that tie same faciii-
'ae.b !!base bwi.-oire been extended to them should be
'lenr ttble fai ir cimatane's of the e ne, ttis braneih
-- largea rporlioti of het whole atnount
I i 'Il 'i' -ew to ldin r p l at t'ootitoe for lind, gold
i.n. m'l ; ,'* i iI- 'i i, iC* i ,,, 7, i ,.] lilr r w ilt natbe
S *' i, -i i i,',, I. I,.' ,I,, ir. r.est, w hile it
a'--. .. ." hI., in I itm tiOt h i aii. in daily expecta-
'aiui'sin l i" '-- -in rTefsred to from the bank of thle State
in'i ,, I., .-- rai elved shall be executed mime-
',s, ,li siW' eirhd le thee amoeunts as received from timhe rc-
isilugiin %.o 5fpectl IS hIve the honor to be, &c.
"JAMES DUBNO, Ceahicr.
r lie Ts 7'reasury."
re1f of the Secretary was as follows:
TaSAssaY DISPABTM5IT, Ao. 11, 1836.
t'in' o- (thin notes of yur Iunk luy tie receiver at Poun-
s 11'Ih *istmint of yottr etutrintet wish this Department, Ihat
-in II in.. theeh.t hie ustumh teuke your notes to the extent of
- :..v".,' i1 your balin, uondcr the contract, upon your
in --i .'. II thient from him as money, He is auttihorls-
..i.. t way, and to that extent, on your showi-tg
-i' nillt' ; itbut I icanusitt user the reglslatinms i to notes
'I'I "--Isi fir general purpotels.
"| ii, in 't:ry respectfolIy, ,...,r .t.. c.nl -. ri .r 'i
"Secretary of the Treasoury.
'i' -. E- f(r
i 1t-nch Bank of Alabama, Decatar."
inisi l' di rc u.hUlar, and this exception under it, not
vAct t a.jawt c(iuspetinded, but their uniformity de-
'i1,, sl -'ar *' wu')strtt'e/ or1 THE PRESIDENT ALONE, IM-
:iudt, A'f1rBt Co t~su wA IN m SESaION. One portion
-.,.....as aeconmeodteda, itns being allowed to pay
,t',. t,... in convertient banttk notes, whilst hleir
,ilhtt;, swae obliged to pay irt site.'f, ait every cost and
,e, linl tiak of transportation. One bank 's notes
a( Weinl tdo any amount less than 8 500,000 dollars,
r!lAhtivdlhs- of the surrounding Statos, orof I'Tennes-
" '. I ard for every 'dollar coin which
i ..-i T.," Presidential election w tiherin fast
,..; i, aW what feet this indulgence, ant that
-' '- iittl etreular s. to bank notes of Miasi|ilppii
c Mif- 1 nisc ,.bsi.,mo.iippi, mh'd upon the People of the
-lt, Aharm *,ni ,iieiipp,, it is not difficult to
There are a number of other cases which*might be se-
lected from the testimony, thie whole nass of which is sub-
mit ed, but ti e committee has not hald time to report parti-
cularly upon them. The undersigned, however, woult call
the attention of the House particularly to a report of Amos
Kendall and John P. Van Ness, commissioners appointed,
by authority of the President, to receive and report testi-
mony touching certain charges preferred Ib-i .Gassaway;
end also tothe teestimony of Commodore Morris and Charles
W. Goldsborough, in relation to said charges, in the appen-
dix to the journal of this committee. One thing is re-
sioners it seemed issued SUBPOENAS for witnesses in the lfrm
of "request," and it is believed that one or ,oth of them
administered corporal.4 aths. How far the constitution of
this tribunal was in the competency of Executive autho-
rity, the undersigned is not prepared to say. But this [they]
are prepared to say: that, whilst the President was de-
nouncing this committee as worse than a Spanish Inquisi-
tion, he should have looked well to his own acts in insti-
tuting commissions of inquiry. Certain it is, that though
these comUissioners reported very'strongly against several
officers in the Navy Department, not one of themt, as far as
this committee is informed has ever been removed from
office.
It had been represented to a member of the committee
;hat disbursing officers had unnecessarily drawn specie
from the deptosite banks, after the issuing of the Treasury
circular requiring specie payments for public lands, and
sold the same as merchandise for their private profit, to
those who required specie at the land offices. This subject
was left unexamined, except by a call on the Department,
which resulted in developing nothing of the abuse. The
subjects of frauds in Indian reservations, and in the pur-
chase and sales of public lands, in comnexion with thie le-
gislation of Congress, as well as theExecutive administra-
tion, were necessarily left untouched, although the atten-
tion of the committee was called to them in various ways.
[See anonymous letters, and the examinations of Amos
Kendall and David Henshaw: sec, also, the letter of R.
T. Archer, and the answer of the Depar:ment to the call
of the committee, on its subject-matter.]
The minority cannot do less' than justice to Col. Tow-
son, the Paymaster General of the Army, by saying that a
complaint was made against his official conduct by a person
named Hobby, and ihe promptly asked for inquiry and in-
vestigatioi, as the best means of doing justice both to the
Government and the -officer; the committee had not time
to examine and report upon his case, and can only refer to
his testimony for the facts of his defence. For other mat-
ters, also of great interest, the minority must refer general-
ly to the testimony of the Honorable H. L. White, John
Bell, Balie Peyton, Frpancis W. Pickens, Henry A. Wise,
Amos Keidall, David Henshaw, John Ross, and others
who were examined. Many who were summoned and
sworn could not be examined ; some for the want of time
and others because they would not have been permittedto
testify as to the matter of evidence for which they were
called..
There is not time, in fact, or opportunity, (part of tjie
journal of the committee having been until the present
moment in the hands of the printer,) to'digest and proper-
ly arrange the facts which have been proved. But, in con-
clusion, the undersigned would humbly hope that the la-
bors of the committee may be fruitful of health and purity
to the administration of the Government. Whether in-
quiry results in vindicating public officers, and demonstrat-
ing their integrity and capacity, or in detecting and expos-
ing their errors of mal-atdministration; their characters on
the one hand, and the interests of the Government on the
other, are well worth the trouble and the cost of inquiry.
The wisest system of laws is no better than the worst, when
corruptly and ignorantly administered; and the worst system
as wholesome as the best, when administered by pure, pa-
triotic, capable, and independent public servants, who act
officially with a single eye to the public good.
All which is respectfully submitted as-a substitute for the
report of the majority. HENRY A. WISE.
FEBRUARY 27, 1837.
[END OF THE REPORT.]
SPRING GOODS.-We have received, and arp now
T opening a large and'general assortment of seasonable goods,
to which we invite the attention of our customers and purcha-
sers generally; among which are the following :
Elegant colored figured Silks of the latest fashion
1 case rich plaid Silks, beautiful colors -
1 do handsome plaid Silks, light colors
50 pieces black Silks, various qualities
20 do elegant Spring Shalleys
100 do French Lawns
100 do Muslin Delane
50 do French Painted Muslins
100 do low-priced Painted Muslins
250 do French and English Chintz
50 do Cambric Inserting and Edgings
100 do superfine Cambric Muslin
50 do do Jaconet do
100 do Swiss and Book Muslins
100 dozen Cotton Hose, comprising general assortment
50 do Ladies' Gloves, beautiful spring colors.
C. E. WASHINGTON & CO.
mar 28-2w [Globe]
FRENCH EMBROIDERY, &c.
J 3 cartons elegant French-vworked Capes and Silencers
50 elegant embroidered camel's hair Shawls
20 dozen Fancy Shawls and Handkerchiefs
10 dozen embroidered and ribbed Silk Hose
100 do Linen Cambric Handkdrchiefs
10 boxes beautiful French Flowers, &c.
C. E. WASHINGTON & CO.
mar 28-2w [Globe]
RI:sH LINENS, SHEETINGS, &c.-
I case superfine Irish Linens, warranted all linenl
I do heavy do do for pillow cases
I do 10-4 and'12-4 Irish Sheetings
1 do 10-4 and 12-4 Russia do
I do superfine Diaper Towelling
1 do Irish and tRussia Table Diapers
25 superfine Marseilles Quills, very beautiful
100 low-priced do.
The above goods were purchased in. New York at auction,
and will be offered at very reduced prices.
C. E. WASHINGTON & CO.
mar 28-2w (Globe)
JERY EXTEN'SIVE SALE.-On Saturday, the 1st
V of April, at 12 o'clock M. I tiall sell at auction, without
reserve, at the National Hotel Livery Stables, the very exten-
sive and valuable stock of Carriages, Barouches, &c. with tihe
fine harness and saddle II.c.ses belonging to the above estab-
lidament, viz.
Handsome close Carriages and Coachees, with harness
Do brass and silver mounted Barouches, with do
Do light buggy \Vagon, with do
Five pairs of well broken harness Horses, in good condition,
anrl have ben carefully used. Amongst these are pairs ofband-
aome maith Horses, with several valuable saddle Horses.
Alno, Saddbl sand Bridles, stable furniture, &c.
Tile carriages andti baronshes are in first-rateo order, built itn
the m,m.t modern style, and of tile best workmanship anid mate-
rials.
Trerum of sale : Catstli for all suing of and under $100; over$l00, and not exceeding (200, i60 days; over 8200, 90 days
credit, for notes satisfactorily endorsed, hearing interest.
Any OtO desiroua of making a purchase of the above it o0e
entire lot, or a part titereaf, has an opportunity of doing so at
private samle previous to tihe 1st of April.
mar 2.5-d&cptB EDWARD DYER, Auct.
ALE O HOUSEHOLD itURNITUE.-Oum
Monday net., :3d of April, at 11 o'clock A.M. I shall
sell, at the dwelling next to S. R. Hobble's, EB'l on 1tl street,
nortli of P treat, the Household Furniture of a lIdy raminoving
from the city; amongst which are
IImdiloiimm sprintlg oait Sofi, Mahlogany Sidteboard,
Gilt Maitlel Gits ittnd ornarmehta
fliot Sotl atnd Winoder Chairs, Iltgrain Carpels & Rugs,
Hall mind Step CarpmeOs, (new,) Fhit brass Stop ltods,
Green Whisomw Blhihil, Best Hair Mattrunenes,
New emlxteail, Bitroaei, Andiron, Tongs nd Shovels,
Fenders, Chalimber Tables &c. &c.
ilotary 4...,tm,,,. '-.,c end appntrtensnce,
Kitlheln It, ml .. '
f t Tlic bove ]eirniturea has been only a short time in use,
atd hm teen well kept.
icir 27---dts EDW. DYER, Auctioneer.
W M M MIT- tPIRHRSON, Attorney at Law and
V Geinetral I danlI Agent,Mclcnt, Arkiansas, offers
Iis tvervIe,-'s fr thii puroImi bitr sI ale. of lands, pibymntit of taxes,
&e. &o. iti ArlutmIanisi d thO hnto Indian purelts hi Missiissippi.
'..l.. It the himiedliato vianiy ,if the Militsry LaindA in Ar-
katismssj Io will ati tany tiin fitrnish infioriii ion concerning
tihill.
Prfessmionl busNineis i promptly attended to.
Bh Run rTO
Chief JIsti(f. lSiberfoon, Lexington, )
Hou. C. Alian, W -inhelotir, Kientucky.
Jolhn J. Maislitll, alZ0,1 lsuisville, 5
Griffen & Whieto n, New Y k
E. U. Berryman, MiA., Ya
Tinomas Paul, Es1. Whmeling, Virginia.
Col. Win. Chirisly, New Orlians.
J, B. Thirasher, Esq., Port Gibson, Misslusiippl.
Col. A. FPowler, Little Roclk.
1,POl SALI, len l thouand acres of choice Cnltion Lind in
toriu'sljized tracts, situated in Alkansas tid Miila ssi ppit s, tie
orf l iin ear the Mississippi river. Also, 30 Lots in lthu town l
Helena. se 14-i-win
WAS HITNGUONT.
71 Ftw S ty iti Union,, noxv anad (tarever, one and
TUESDAY, MARCH 2S, 1837.
LATEST FROM FLORIDA.
The news from Florida is not by any means of
as favorable a complexion as that lately received.
The following is an extract of a Letter receiv-
ed by tihe Editor of the Charleston Courier from
St. Augusline, under date of March 17:
An express arrived here from Gen. JEsuP this morn-
ing, bringing despatches as late as the 12th of March. We
understand ihe is not so sanguine as to the result of the
treaty lately entered into with the Chiefs, as would appear
from the letters published in our last. He expresses doubts
as to the ability of the Chief's to govern their people, andti
particularly their young men. And he also doubts the faith
of Philip, Chief of the Topkoliky Indians. Philip has a
Information also reached Charleston, on the
20th, by Captain Southwick, from St. Augustine,
that a few moments before his leaving that place,
an express arrived from Picolata, dated the same
morning, (18th inst.) which stated that the In-
dians attacked that place the previous night and
were beaten off-ftrther Capt. S. could not learn,
but this can be relied on. The bugle was sound-
ing as theMills was leaving the harbor; it was said,
for Capt.Hanson's company to muster and march
forthwith to Picolata, or in that direction. Cap-
tain S. did not understand what the result was,
only that the Indians were beaten off, they car-
rying with then some horses.
From Volusia we learn, (says the Charleston
Courier,) that orders had been sent to Col. FAN-
NING, by Gen. JESUP, that in case he should re-
ceive no orders from the latter to the contrary
by the 7th, he should again take the field. In
consequence of these instructions, Col. Fan-
ning, with his command of about 500 men,
marched on the 8th for Lake Monroe.
FROM NEW ORLEANS.,
The slips due at this office by the Express
Mail from the South came to hand, in part, by
the regular (irregular) mail papers received from
the Post Office yesterday morning. They were
of the date of the 17th and 18th instant. The
following is the latest allusion that we perceive
in them to the commercial embarrassments in
that city :"
OFFICE Op TiHE TauE AMEHICAN,
FRIDAY, MARCH 17, 1837.
We have nothing now to communicate relative to the
money market. Situated as we are, no great change either
for better or worse can take place without predisposing
causes from New York. We are so subject to the influ-
ences of the state of the money market in that great empo-
rium, that we can scarcely hope for any independent action
in our own monetary concerns. Cotton has declined from
I to 1 cent. The causes of this depression must be found
in the derangements occasioned by the late suspensions.
In truth, cotton has always been held in this city too near
the Liverpool prices for doing a safe business. No one
could enter the market but the heaviest capitalists at such
rates, and hence the tendency to a monopoly. But the
time is coming, rapidly, that the transactions in cotton must
be open to competition, and the trade will then be restored
to a healthful condition. The sales recorded by the board
of brokers, to-day, are only 112 bales of Mississippi at 12h
cents. Large quantities are arriving, as will be seen by
reference to our statement.
NATIONAL CIVILITIES.-The following is an
extract from a letter from an officer of the U. S.
ship John Adams. The action recorded, and
the note from the Captain of the English ship
relieved in the hour of peril, are both creditable
to the parties concerned :
Extractfrom a letter of an officer on board the Eited Stlates
MALAGA, January 11, 1837.
On the 2d, it commenced blowing from the east at about
one in the morning, and continued until four in the after-
noon, when it became a complete hurricane. We had as
much as we could do to take care of our fine ship. We
sent down every thing to our lower masts, and we receiv-
ed but very trifling injury. There were three English
men of war here ; one arrived the night before the gale.
She had to cut away all her masts, and is otherwise injured.
One of the others lihad to heave over all her guns, and was
about cutting away her masts, when tile gale abated. The
other, the largest of the three, lost her rudder, besides re-
ceiving .farther damage. Six rmerchantmen were wrecked,
but none of them Americans. Our captain sent his largest
boat to the assistance of theship that was dismasted, and
succeeded in getting one of her cables on shore, which was
of great service to her. The following is a copy of a let-
ter received from Lord Ingestrie, who commanded the larg-
est ship: -
H. B. M. StIp TYRE, MALAcA, Jan. 5, 1837.
SiR : It is with infinite pleasure that I, in the name of
you, your officers, and ship's company, our best thanks for
the, kind ani cheerful assistance you were so good as to
giye us during our critical position in the late gale. Ihave
to request that you will have the goodness to make this
communication to those under your command.
I have the honor to be, sir, your most obedient, humble
servant, INGESTRIE, Captain.
To Captain SILasH. ST'RINGIInAM,
The Democracy of the Senate [of VIRGINIA]
have stricken from the Preamble to the Resolu-
tions censuring Mr. LEIoG, the sentence the
voice of the People is the voice of God." This
is a specimen of exceeding modesty and conde-
scension on the part of the wise men who sit in
the upper chamnber.-Whig.
PROM THE SAC.EM (MASS.) REGISTER.
S'eamen's Hospital Tax,-The Fall River Pa-
triot says :
A statement is going the rounds of the newspapers,
that the Hospital Tax is repealed for one year, and that
an appropriation of $150,000 has been made to sustain tihe Marine Hospitals during that period. We are inclined to doubt this; if our recollection serves us, the clause touch- ing the hospital money was lost by the carrying of the pre- vious question." The Editor of the Patriot is mistaken; an amendment to theli Harbor Bill, suspendinig the payment of the Hospi- tal Tax for one year, andi appropriating$150,000 to sustain
the Marine Hospitals during that period, was moved by
our representative, (Hon. S. C. Pn.tielPS) atud was carried,
as follows
Provided, That from and after the first day of April
next, all laws enacted, whereby seamen are required to
pay twenty cents a month, or their employers arc required
to retain that sumni out of their wages, to crea. e a fund for
Ithe sick rttd disabled senitien, shall be suspended for one
year, during which no such exaction shall be made; and
that, illtemuad of said tax, they're be appropriated, out of any
money in the Treasury nuot otherwise appropriated, the
sum of one hundred and filly thousand dollars, to be dis-
bursed ill the same maniur as the sum above mentioned."
We trust that at the next session of Congress this tax
will be repealed ; and we mgree with the Editor ofthe Pa-
triot, that with such an overflowing Treasury, it would
seem that our Marine Hosp'tals might be supported with-
out the collection of twenty cents a month fron-our hardy
and generous hearted soamen, especially since a large por-
tion of them robust personally ever be beyond its beneficial
influence."
FROM MEXICO.
We take from the'New York Daily Express the
following Extract of a Letter from a Mexican in
Tampico, to William Kidd, Esq. of the Mer-
chants' Exchange, New Orleans, Ithe contents
of which are said to be !he'ievt'd tbe entirely
true by those actually acquainted with the state
of affairs in Mexico :"
"Dear Sir: Notwithstanding the nonsensical rant in
the American papers concerning this country, and the ex-
pedition destined to operate against the Texans, you should
know that the Mexicans and the Government areresolved
to make Texas enter into its duty, and they will do so.
Every thing is now ready for the march of the troops,
which are composed of 6,000 infantry and 1,200 cavalry,
with their corresponding artillery; and the command is
confided to General Bustamente, well known for his valor
anti patriotisam. Although with a great trouble, therechave
been equipped four brigs, three schooners, and eleven gun-
boats; and there are expected daily from Jamaica two good
steamboats and one brig, under the command of William
McKenzie, who served with Commodore Porter in the
war of independence. As soon as these vessels arrive,
about 1,000 men will be embarked to operate by sea against
Galveston, and the other troops will go by land, to unite
with them, under the command of Bustamente. The ar-
'rival of Santa Anna will not change,, in the least degree,
the'aspect of things in Texas, because he has agreed with
Bustamiente and our Government; and I repeat that the
expedition will start about the middle of March, if not
before." '
We find in another New York paper the fol-
lowing Letter, which appears to have been copied
frotn the Government paper in the city of Mexico:
LETTER R OM COL. ALMIONTE.
To his Excellency General Don Jos6 Maria Tornct:
Vera Cruz, Feb. 20, 1837. Much esteemed Friend:
I improve the few moments afforded me by the express
which is going to set out, to inform you that, through the
favor of Divine Providence, we have got out of the claws
of the banditti of Texas, and of their SYMPATHIZING friends.
We shall soon see each other, and you shall know our
long chain of sufferings.
I beg you to forward immediately the annexed to my
house, and send me, if you can, the answer to Manga de
Clavo.
The President [Santa Atna] comes sick, and "will not
be able, I think, to recover for many days.
JUAN N. ALMONTE.
Licut, Col. FosTER, of the United States Army, arrived
at New Orleans on the 15th inst., from Tampa Bay, with
intelligence that the war with the Seminoles was (as be-
lieved) brought to a close. Col. F., with another officer,
accompanied by two private soldiers, travelled more than
one hundred miles through the midst of tlihe Indian coun-
try, oil their way to Tampa Bay, without being molested.
HERALD OFFICE,
NnoRFOLK, SUNDAY, MARCH 26-2 P.M.
Awful Coif'laglraton it IVashinmg/on, N. Carolina.-We
have verbal accounts of a desolating conflagration in the
town of Washington, North Carolina, which broke out on
Monday night last, and destroyed sixty-fobur houses;
but our information does not extend to particulars. The
fire, it is said, originated in a turpentine distillery, and
swept away the entire business part of the town. A vast
quantity of naval stores was destroyed.
Supposed Loss of another Emigrant Vesscl.-There
was a rumor in Liverpool when the packet ship North
America sailed, of the loss of the British barque Jane &
Margaret, bound from Liverpool to New York with 188
passengers, on the Irish coast, near Arklow. An Irish
trader, which arrived at Liverpool on the 17th February,
reported that, when off Arklow, she picked up some cases
of goods, the marks of which were found to correspond,
with some goods shipped by the above vessel.
We understand that the family of the illustrious MAnt-
soN are preparing for the press five or six volumes of his
MSS. One volume is to be devoted to Constitutional Doc-
trines, and the others to his interesting Correspondence.
These are, of course, exclusive of his Reports of the old
Congress and of the Federal Convention, for the purchase
of which the last Congress have appropriated $30,000.- Richmond Enquirer. A LAUNCH EXTRAORDINARY.-A SHIP FROM THE COUNTRY. A correspondent of the Ellsworth (Maine) Radical, un- der date of Blue Hill, March 17, 1837," gives an inter- esting.account of the launching of a vessel as follows :. On Wednesday of last week, the 8th instant, we wit- nessed with considerable interest what seblom occurs in this country, and never was before seen in this place-a ship coming out of the country .on dry land. A vessel of seventy-two tons burthen, built by a number of the farm- ers of this town, at the distance of three and a half miles from salt water, was moved by the power of men and oxen into her destined element. At the time appointed about 60 yokes of oxen and from 400 to 500 men and boys appeared on the spot. The ves- sel was placed upon a sled made for thi purpose, about 30 Feet in length and 8 feet in breadth. To this sled the oxen were attacTied by means of two chain cables, and arrang- ed in two divisions so as to draw side by side. Two haw- sers wore attached to the quarters of the vessel, on either. side. By these a crowd of men drew with no little power, either forward or aft, as their power was needed to aid the oxen in going ahead," or to nullify their power in de- scending hills. Two ropes were also attached to the bow- spfit, by means of which 20 or 30 men on each side guided her with ease. At a little past 9 o'clock A. M. all was ready, and the word given to proceed. Some little difficulty occurred at the outset, but soon all was in order, and moving forward with great regularity and ease. In descending some ofrthe sharpest hills, it was deemed expedient to place a part of the team iu thea roar to prevent too rapid a descent, so that for the greater part of the distance she was drawn by'30 yokes of oxen, together with thie aid afforded bly the men. The whole eompauy dliued on the road, anil the oxen were bailed, which necessarily took' up considerable time ; but still, in six hours from the hirst move, she was safely landed on the ice some distance from the wharf: not thie slightest accident occurred, nor was the least disorder witnessed during the day. Tothose who never witnessed the like, their sight must have been one of no ordinary interest. To sece a vessel of such size and weight, preceded by a team so long, accom- panied by such a crowd of men, admi all in perfect order, moving slowly forward with majesty and ease, traversing hills and valleys, passing through woodlands and open plains, plunging through snow drifts aisd skating upon the ice, still holding her course onwards towrnls the sea, had, indeed, quite aim air of -tha sublime. hIt is p roper to remark that this vessel lias been built and hatlod without the aid (or, to speak more accurately, with- out the hindrance) of spirits. This accounts for the per- feet order whiich prevailed at the hauling, and the safety and despatch with which it was accomplished. A TRICK.-A fellow exhibited, in Vienna, a young girl stained with walnut juice, as a veritable wild Esaquinmaux! Upon the deception being discovered, he was imprisoned, as he deserved to be. WHEELIG, MARCH 23. SUDDENo DATII.-JOHN C. GRAY, frmni Boston, arrived here on thIe 2d iainut, mand took lodgings at thle Virginia Hotel. It was shortly ascertained that hlie ws a hypochondriac of le most untiiHrtn te aundi pitliablle ktind--ollen iinlgining htimselfseritun- ly afflicted in various' -h,:.Il .1 ....1 often ludicrous ways-somne- times Ithat i e was it ....I.. ...i i -- and the least touch would breuk him;at other times that hlie wns snow, id lthe fire would melt himin. He ot.en applied to a drug store for medicine, andi on Monday lie procured an ounce of opium, a part of which lie took. Promn that time, lie bamine languid, though lie did not go to sleep until late in the evening. On Tuesday morning, he was found dead in Ilss bed. A coroner's jury was summoned, adl evidanec ltaon. Those acquanted wi ll him express the opinion that hlie did not take the opimn in the belief thatit would kill iln. h-is i:manners in lucid intervals, and his general ap- pearance, evinced a good education and respectability. We nu- detrtand his relations in Boston are wealthy and respected. [ Times. THE ARMY. We have before us (says the Political Arena) the official Army Register for 1837. It presents a frightful list of casualties in the Army since the publication of th last Register, viz. itSIGN.t TIONi. C.lonels 2, Captains'20, Ist Lieutenants 40, 2d Lieu- tenauts 37, Brevet 2d Lieutenants 13, Staff 3-Total re- signations, 115. DECtINED. Lieutenant Colonel 1, C;ptain 1, 1st Lieutenants 3, 2d Lieutenants 1, Brevet 2dl Lieutenants 1I-Total declin- ed, 7. DEATIuS. Lieutenant Colonels 2, Brevet Lieutenant Colonel 1, Brevet Majors 5, Captains 9, 1st Lieutenants 7, 3d Lieu- tenants 5, Brevet 2d Lieutenants 1, Medical Staff 3-To- tal deaths, 33. SDIS.MISSED. 1st Licutetrant, 1. nCECAPIt, tTTON. Resignations 115, declined 7, dcaths 33, dismission 1- Total 156. MILITARY APPOINTMENTS BY THE EXE- CUTIVE OF MARYLAND. For tile 53d Regiment, Baltimore city, JoutN SPE.a NI- cuor.AS, Colonel, vice Walker, resigned. SAMUEL OwinGs H t.OFFMAN, Lieutenant Colonel of the same. For the 4th Brigade, SAMUEL COE, Brigadier General, vice Briscoe, resigned. For the '2d division, JAMES SEWALL, Major General, vice Forman, stricken off for not reporting. For the 1st Brigade, ISRAEL D. MAULSBY, Brigadier Gen- eral, vice Sewall, promoted. For tbo-4th division, WILLIAM JAMESON, Major General, vice Stansbury, stricken off for not reporting. For the 11th Brigade, JosUA TAYLOR,t Brigadier Gene- ral, vice Jameson, promoted. For the 12th Brigade, WILn.t.M POTTERn, Brigadier Gen- eral, vice Dickinson, resigned. For the 1st Regiment, 1st Regimental Cavalry District, JOHN MCPHERSON, Colonel, re-appointed with rank from 30th December, 1829, the date of a former commission. WILLIAMt, McPHERSON, Lieutenant Colonel. RICHARD JOHNSON, of William, Major, vice McPherson, promoted. For the 2d Regiment, 1st Regimental Cavalry District, Tnoaas -HOOK, Colonel, ro-apipointed with rank from 3d February, 1827, the date of'a former commission. JAMBs (C. 4Tr.s:E, Lieutenant Colonel, re-appoirited with rank from 23d October, 1833, the date of a former commnis- sion. For the 2d Regimental Cavalry District, Jontx CONTEE, Colonel, vice Winsor, declined. THOMAs. G. PR.XTT, Lieutenant Colonel, vice Dunlop, moved away. For the 3d Regimental Cavalry District, GEOEGE How- ARD, Colonel, re-appointed with rank from the 14th Feb- ruary, 1834, the date of former commission. ALPREDn SEt.,MAN, Lieutenant Colonel, vice Cooke, stricken off for not reporting. For the 4th Regimental Cavalry District, DANIEL JENI- ran, Colonel, vice Causin, moved away. For the 6th Regimental Cavalry District, JosIUA C. GtST, Colonel, vice Wilson, stricken off for not reporting. SWILLIAM TAGART, Lieutenant Colonel, vice Gist, pro- moted. Forthec7th Regimen!al.Cavalry District, AQLILA BRowN, Colonel, vice Rutledge, stricken off for not reporting. CLEMENT BUTLER, Lieutenant Colonel, sice Brown, pro- moted. AMERICANS ABROAD. Extract of a letter to the Editor, dated RoME, FEB. 2.-We have met here a considerable num- ber of our countrymen, the most distinguished among whom are Commodore Hull, Mr. Binney, and Mr. Tick- ner-more distinguished, I can proudly say, in their res- pective walks, than any other here. The English are not as numerous as usual. The Pope has forbidden the use of masks during the carnival, because, as is said, he fears revolution. The consequence is, the people are extremely sour. Many of them make money by this folly, and most of them receive great enjoyment. It is particularly a holiday to the priests, who, in fantastic dresses and masked, give loose, during the carnival, to any portion of the devil not driven out of them-how much this is you can guess as well as I. In consequence of the cholera at Naples; which has cut off all intercourse between the Roman States and the southern portion of Italy, and thereby much abridged the little commerce these people have, as well as the influx of foreigners, the people are suffering unusual distress from want of food. They are indeed driveit to such extremi- ties, that the bakers and victuallers cannot take round their wares without a guard of soldiers, and this is not always a sufficient defence, as there are daily instances of the guard being disarmed after a scuffle, and the provisions -distri- buted among the assailants. The crowd of beggars and idlers about the streets sur- prises and disgusts us more thanan n be conceived, parti-. cularly when we refer this state of things, as we must do, to bad government. -They are handsome, sprightly, intelligent people, but in ptofound ignorance, ant tiey are kept so design.,dly by their Government. A different state of things would des- troy this civil and religious cheat in a moment. On visiting one of the churches, St. John Lateran, the second in importance here, and looking over some ancient books, for the offices of the church, I asked the attending priest for the Bible. He said it was not in the church! but was preserved in the consistory room. I asked him when it was read io the people: "On the day of Petite- cost," was his answer, some portions of it are read." In fact, none but the learned are permitted to read the Bible-which, moreover, is forbidden to be sold. However, you know all these things as well as I, and have seen them.. How I wish that all my countrymen could be persuaded of the happy condition in which our virtuous and wise forefathers, under the guidance of Divine Providence, have placed them-that they might, uninflu- enced by thle love of change or the arts of demagogues, preserve in its purity the government which secures such blessings to them.-N. Y. American. TENACITY, oP i.PE op TiE AIt,'Lm TREi.-A medical gentleman who has recently made a tour through several of the Western States, related to us the following singular instance, illustrative of the power of the apple-tree to sup- port life out of the ground : In tile mlionth of October, 1835, Mr. Alex. McCoy, liv- ing near Columbus, Ohio, bought ofa nurseryman on Long Island 100 apple trees; they were thlen packed up, ship- ped via the great Eric canal and the lakes, to Cleveland, Ohio. On arriving at that point, ilhe canal being frozen up, the trees remained there until the later cnd.of March, 1836, when they \vere sent to Columbus, Ohio, by the canal; they reached the latter place in the month of April following. As it was presumed that thIe trees, whiich had now been out of the ground six months, were all dead, or their vital powers so far destroyed as to render their vege- tating not only doubtful, but, as was supposed, hopeless, the owner refused to receive them. In this situation they remained till May, when the agent of the canal forwarded them to their proprietor, who planted them out in his corn- field, rich limestone land, and tended them with his corn. At the period of planting, which was seven months from thie time of their being taknu up, tise trees were partially its leaf, and notwithstandintg all of these disadvantageous circumstances, 98 of them lived, only 2 of the hundred dying. Nantucket is what the New Englanders call a froze and thaw." The whole concern hlias been frozen as hard as sea b biscuit tdring the whole winter, and his but just shook off her icicles. The Inquirer thus discourses spring music: A scarcity of nearly all thle necessary articles of consump- tion has at lengtlli come upon us. The stalls in ourt markets inuv louug heee swept eleam ; our tmef uad pork barrels are itt- torly bereft.; time woodwhiimlingera have disposed of thme last catstick ; there is scarcely any tling eatable or burnable to lIe procured, even for money, thit all-commanding agent; time clam, banks have suspended dliseutnts, the wild fowl alre extcr- initiated, the very eels have wriggled into the value of sixpence a pound, nnd we are still bl cked by ice, in a manner so ambi- guous however, as neither to suffer navigation to,move, nor men to travel on its surface. Here are 7000 mouths to be fed, and as many bodies to be warmed. Vessels can iconme ad go, to atntd t from Brant Point, nalthotglt earcraft still lies embodied in the frozen docks. Oh! for a few cargoes of food and fire- wood from Connecticut, Cape God, and all along shore !" P IANO FORTES.-Just received, fmoir splendid Piano F'ories, direct from one of thie best houses of Germany. They are warranted, and will be sold on very accomuiiodaling terms. Expected by first arrival fi'om Boston, fiur Piano Fortes from the celebrated factory of Messrs. Gilbert & Co SAMUEL CARUSI. moar 27-colmd&c (Alex. Gaz.) THE EXPRESS MAILS. From the SOUTH, by the Express rider last evening, nothing at all received. From the NORTH, a single slip from the office of the New York Mercantile Advertiser, which mentions the arrival of the fast-sailing ship Re- publican, from Liverpool, whence she sailed on the 25th of February. The news from the Con- tinent, by her, is no hlter than has been hereto- fore received. The following is the latest ac- count of the state of the Cotton Market: LIVERPOOL COTTON MARKET. FRIDAY Ev,'tINo, February 24.-The very low business transacted in American Cotton at the close of last week, under he. continued pressure of money, attracted the at- tention of buyers in the early part of this week; and from ihe improved demannd upon the market on Monday and Tuesday, it rallied to id. per lb. This advance has not, however, since been maintained, and the market closes to- day at only id to jd per lb. above our last quotations. In Brazils little has been done, and this little is at rather low rates. In Surats there is no change. A letter from Liverpool of the 25th, referring to the state of the Cotton Market as discourag- ing, says : The alarm among bankers is great, (we may say excessive,) and all capitalists 'are endeavoring to pull in as hard as they can." MARRIAGE. At Brown's, in this 'city, on Sunday, the-26th March, by the Rev. Mr. Tippet, Mr. JOHN HARRISON BUSH, to Miss HANNAH ELIZABETH GRAY, both of Charles county, Md. SHIP NEWS-Powr OF ALEXANDRIA. IASRIVED, MARCH.25. Schooner Ringgold, WescotI, Newbcrn, .N. C.; shingles to order. Schooner Flowers, Thompson, Newheborn, N. C.; shingles to P. Waters. Schooner Margaret, Marsdon, Richmond; coal to Wash- ington. SAILED. Schooner Washington, Rice, New York. W ASH.INGTON LIB1AARY.-The Stockholders of the, Washington Library will take notice 'that "i elec- lion oF seven Directors will be held at the Library rooms on theli first Mionday (3d day) of April next. Polls to be open from 3 o'clock to 6 o'clozlk P. M. JOHN SESSFOnD, EDWAlRD IGLE, and LAMBERT TtEE have been appointed Judges of Election. No Stockholder will be allowed to vote whoshallbe in arrears to the institution. By order of the Board. rnar 28-eo3t 1 0. 0. I} -The members of Washington Lodge, No. 6, are requested to attend a meeting of the Lodge at th-Air Hall on C street, for the purpose of electing officers for the en- suing quarter, on Tuesday evening, March 28. mar 28 JOS. SMITH, Secretary. E ASTER BALL.--Carusi's Assembly Rooms.- L. CARUSI respectfully gives notice that his large Sa- loon will be prepared fr .the reception of visitors on Tuesday, the 28th instant, being his Eighth Cotillion Party for the sea. son. Those wishing to enjoy the festivity can purchase tickers (at S1 each) at the Saoon, and at the door on the eveningof the Ball. (Globe) mar 21-cotd NOTICE.-Washington Branch Raiiroad.-On anil after Saturday next, the t.t of April, the hours of departure of the evening train of Passenger Cars from Baltimore andl Washington, respectively, will be as follows, viz. FROM, BALTIMORE FOR WASHINGTON, At half past-4 o'clock P. M., instead of quarter past 3 o'clock P. M., as at present. FROM WASHINGTON FOR BALTIMORE, At three-quarters past 4 o'clock P. M., instead ofhalf past 3 o'clock P. M., as at present. mar 28 (Glo. Reformer, Met. & Alex. Gas.) OARDiIN.G.-Mrs. C. WOLFENDEN, on Pennsylva- .nia avenue, directly opposite Todd's drug store, having put her house in complete order, would be pleased to receive a fbw summer boarders. (Globe) mar 28-eolw A N EXCELLENT CARRIAGE and HORSES SFor Sale.-On Tuesduy afternoon 28th instant, at 5 o'clock, in front of Brown's Hotel, I shall sell at auction, (if not previously sold at private sale,) a very handsome Carriage, with harness brass nmounted made in a superior manner to order, in the latest fashion. With a pair of very fine, active, and well- broken Bay Horses, 7 years old. EDWARD DYER, mar 27- 2E Auctioneer. W E want immediately a good Salesman. One who is sc- q quainted with the citizens of this place would be pre- ferred. BRADLEY & CATLETT. war 28-3taw2w (Globe) SALT AIF'lOAT.-30,000 bushels of St.. Ubes Salt, the cargoes of the ships John Marshall and Maryland, for sale by HENRY DAINGERFIELD, , mar 20-dlw Alexandria. ALUABL[E PROPERTY F'OR SALE.-Tho slsubscriber, being deterinied to remove to t he West, will sell all of his Real Estate-his Tavern Stand, in Rockville, Montgomery county, Mdrl., known as the FARMERS' HOTEL. The house is two stories high, built of brick, 40 feet front, 37 feet deep, back wing 40 feet-a well with a pump in itofexcel. lent water in the yard. Stable 36 feet by 40, with two sheds o? 10 feet each. Also, a first-rate garden. This property is very desirable, it being located on the north side of the public square, and fronting the Court-.house, and one of the best stands in the place. Also, a lot of land containing 1| acres, with a building ilireon. The house is a new one, 18 feet by 24, one and a half itiries high, and built of the best materials, and tlhe land is in a high state of cultivation, and well set in grass. Also, a lot of ground lying ini tlie forks of the roads leading to Washington nnd Georgetown, near the Ranan Catholic Church, rontaining about 2 acres. This land, being in a high state of cultivation, and well set in grass, would be an excellent situa- tion for a butcher or gardener. Any person wishing to purchase the above described property or any part of it, can be shown the same by calling oni the sub- scriber, at the Farmers' Hotel, Rockville, Montgomery county, Maryland. F. KIDWELL. N. B. Persons indebted to the subscriber will call and settle their accounts immediately. F. K. fetb tI-cptnmar3 I A CtLASSICAL TEACHER WANTING AN ESTABLISHMENT.-The-advertiser, a graduate of Trinity College, Dublin, a married iman, upwards of 40 years orf age, wio has had more than twenty years' experience in clas- sical instruction in the United States, and has.been Principalof several academies in Virginia, wishes to obtain a situation in a respectable seminary, in which hIis attention will be confined exclusively to instruction in thie Greek and Roman languages and literature. A liberal salary will be expected, anti satisfac- tory testinonials of ability and moral character will be given from some of ths most distinguished characters in the Union. A healthy locatiot- in the State of Maryland, in the rneighbor- hood of WVashington or Baltimore, will be preferred; but if suf- ficient inducement is held out, the advertiser would move to Charleston, South Carolina. His present engagement will'Fter- minate in a few months, and hlie wishes to make his arrange- nlents for a change as early as possible. Address, by mail, to Q, teacher, Richlmond, Virginia. mar 9-eolm TOTICE TO EMIGRANTS.-The subscriber, be- .'I ing connected with the Pit'sburg lines ofsplendid Steam Packets to Wheeling, Cincinnati, Louisville, and St. Louis, in forms emigrauts froi-n Europe and the Eastern States, going West, also those bound to Texas for the purpose of locating themselves or colonizing on the lands belonging to the Colorado or Red River Laud Cotipany, that lie lias made arrangement. fir their reception immPediately on their arrival at his STiamboat Stores, Water street, Wheeling, from whence they can be sent on board without delay, subject to no charge whatever for ser- vices rendered by the subscriber. This arrangement is made in consequence of the difficulties encountered in notbeing enabled to obtain mshelter-for themselve- or a depot for their goods. Editors in England, Ireland, and the ports ofembarkation if- Germany, will pllromnote the interests of their countrymen by inserting this notice. JOB STANBERY, feb 2.3-eonlt .V Wheeling, Virginia. N. B. 'Those bound to Texas will please call on Win. Bryan, No. 36, Old Levee street, New Orleans. JOTICE.-Tne subscriber wishes to exchange some va- -L Inable LANDS in Louisiana, say 2000 acres, for Negroes. The land is well adapwtd to the cultivation of cotton or sugar." lie is also desirous to enter r into partnership, for the purpose of cultivating cotton or stirar, with any one owning slaves vwh nay wish to embark in that lucrative branch of iotdstry. For fltrther information apply to G. WATTERSTON, Washington, or to GEORGE W. WATTERSTON, lmar 18-2naw4w New Orleans. -rOTICE.-The C olaictorshipslor tle Washingto National SMomnumtent Sociev in the following Statesand Territorie% viz. New Hampshire, Rhode slalnid, Vermont, Maryland, Flored da, South Carolina, Arkansas, louisiana, and Alabama, are at present vacant. Persons desirous to act will make applientioO to the subscriber, post paid. GEO. WATTERSTON. mar 13--3wlaw Secretary. NAVY COMMISSIONEiS' OFFICE, MARCH 18, 1837. 5 "L IVE OAK TIMBER.---Sealed offers, endorsed Ofersfor Live Oakfor smallvessels," will be received at this oilice until 3 o'clock P. M. of the first day of July next, for the supply of Live Oak Timber as follows, viz. No. 1. For the frame timber anld keelson pieces, and tihe promiscuous timber for one sloop of war, (small class,) to li e de- livered at the Navy Yard, Charicstown, Malssachusetts. No. 2. For the frame timber, keelson pieces, and the pro- miscuous timber for one sloop of war, (small class,) anti one smaller vessel, to be delivered at time Navy Yard, Brooklyn, New York. No. 3. For the frame timber, keelson pieces, and promiscu- ous timber for one smaller vessel, to be delivered at the Navy Yard, Philadtlphia. No. 4. For the frame timber, keelson pieces, and promiscu- ous timber for one sloop of war, (small class,) to be delivered at the Navy Yard, Washington, District of Columbia. No. 5. For the frame timber, keelson pieces, and promiseu- ous timber for one sloop of war, (small class,) to be delivered at the Navy Yard, Gosport, Virginia. The quantity and dimensions of the promiscuouj timber for each vessel of each class is aa follows : For each loop of war, 1,500 cubic feet, which Must be sided twelve incies, andl be from twelve to eighteen feet long; six of the longest pieces to side sixteen inches. For eactitsmull vessel, 800 cubic feet, which must be sided eight inches, and be fironm ten to sixteen feet long; six of the longest pieces to side twelve and a half inches. A part ofthe promiscuous timber may be got to larger di- mensions, provided thIe pieces will answerfor replacing defec- tive hawse pieces, transonms, breast hooks, or other valuable pieces. Separate offers must be made for cacrofthe preceding numn hers, and each offer must embrace all the timber that is called for by the number to which it refers ; the prices asked per cubic foot must be stated separately for each and every class of vessels embraced in the offer, and for the promiscuous timber of each, *class separately from the other; all of which other is coiTsidered anoulded timber. The whole to be delivered before the first day of July, 1838, and as much sooner as practicable. The said Live Oak Timber must have grown within twenty- five miles ofthe acabord, (which must be proven to the sutisfac- tion of the respective cuommnfidants,) must be got out by the moulds and written directions and specifications of dimensions, &d. which will be furnished fo contractors fbrtheir government; and must be free from all injuries and defects which may impair the good quality of the said timber for the purposes-for which it is required by contract, and be, in all respects, satisfactory to thee commandants of the respective navy yards where it is delivered. Bonds, with two good and responsible sureties, whoseb names must be forwarded with the offers,) in the amountof one- third the estimated value ofthe timber to be furnished under the respective contracts, will be required; and, as collateralse- curity for the faithful compliance with the terms, stipulations, and conditions of the said contracts, ten per centum will lie re- served from the actual amount of each payment which may he made, from time to time, within thirty days after bills shall be i duly approved and presented to the Navy Agents, until the said contracts are completed and closed ; which reservations respec- lively will be forfeited to the use and benefit of the United States, in the event of failures to deliver the timber within the respective periods prescribed by the contracts. The moulds will be furnished to the contractors at one of the Navy Yards, Brooklyn, Gosport, or Philadelphia. 't To be published twice a week, until 15th June next, in the National Intelligencer, Globe, Eastern Argus, New Haump- i shire Gazette, Commnercial Gazette, Boston Morning Post, New York Times, New York Evening Post, Trenton Emporiunn, Pennsylvanian, American Sentinel, Richmond Enquirer, Nor- o folk Herald, Raleigh Star, Charleston Patriot, Georgian, Pen- sacola Gazette, Lrnisiana Advertiser, Mobile Register. N mar 21-2awtlSJ OARDING.-Mrs. MOUNT, a few doors east of Mr. Gadsby's Hotel, on Pennsylvania Avenue, is always pre- pared f.r the reception nf boarders, either by the day, week, month, or year. Citizens, as well as strangers, will find plea- sant apartments, and comfortable accommodations, on thei most moderate terns, arid she pledges herself to give every al - tention. mar 16-co3t PENSION AGENCY, CITY OF WASI-IIN'. - TON.-NAVY PENSIONS.-The widow, or if no widow, the children ofany officer,,seaman, or marine, who mn3 have died at any time and from any cause, while in the naval service ofthe United States, is entitled ion pension, and Irom thbr time of the death, a widow till her death or intermarriage, and the children till the age of twenty-one years.. And in all such cases, when a pension., has been granted that does not run back to the death of the officer, seaman, or marine, arrears are due on that account;, and when held tiy a child, five years' arrears are now due or will become due, that is, from the former limita- tion of sixteen years of age to lihe present extension oLticenty- one years of age. Anyofficer, seaman, or marine, who may at any time have been disabled by wounds or injury while in the naval service, is entitled to a pension front the dte of such wound or injury ; and ifnot heretofore pensioned to that extent, is now entitled ti. arrears on that account. S Those having failed to make application, those having applied and not succeeded, and those having obtained a pension that does notrun back to the death or disability (as the case may be) or, if a child, was restricted to the age of sixteen years, should lose no time in ascertaining their right. The undersigned having devoted much attention to this sub- ject, and being now prepared to make his efforts beneficial to claimants, invites them to transmit to him, forthwith, (post paid,) a brief sketch of their ca-e, with a full power to adjust and re- ceive in all cases of arrears in which a pension has been grant ed, which shall have instant attention. The undersigned, being wil known, deems it only necessary to refer to members of Congress generally. JAMES II. CAUSTEN, mar 11-d4l&law4w Washington City. The Daily Advertiser, Portland, Maine, Portsmouth Jour- nal, Portsmouth, New Hampshire, Boston Courier, Boston, Mas- sachusetts, Now York American, New York, Poulson's Daily Advertiser, Philadelphia, Baltimore Patriot, Norfolk Herald, anti Charleston (S. C.) Courier, will copy the above, and send accounts as above. F O TH-E TRUSTEES OF THE ROCKVILLE ACADEMY : GENTLEMEN : At this early date I re- spectfully apprize you of my wish to dispense with the scholastic portion of my labors, and my intention to resign the office o! Prin ipal of the Rockville Academy on the 14th uf-April next, which day will terminate a connexion with you, as a Boiid, for -fifteen. years. In the anticipation of surrendering into your hands the trust confided to me, I assure you, gentlemen, I have great pleasure in the recollection that, during this-whole period, no circumstance has ever occurred to interrupt, for a moment, the harmony and friend.shipsubsisting between us. It is, more- over, very gratifying to me, soon about to retire, to leave the academy in a-highly prosperous condition, having nearly one hundred pupils, witlihtwo competent, faithful, and effthcient teach- ers in the Mathematicaland English departments. In the hope that, under the direction of Divine Providence, you will be able to select a Principal possessing the necessary qualifications and weight of character for the highly responsible office, and with my best wishes for the lasting prosperityof the institution under your carol, I am, with sincere regard, your obedient servant, JOHN MINES. Rockville, Jan. 14, 1l37. As it will be seen from the foregoing communication to the trustees of the Rockville Academy, that the Principal, the Rev. -John Mimes, lihas resigned thle office of Principal in that institu- tion, a vacancy, therefore, has occurred; and the trustees wish to engago a gentleman of high moral character, who can teach Greek, Latin, the higher branches of Mathematics, Moral and Natural Philosophy, and Geography, and who is thoroughly ac- quainted with the duties of an academy. To such a one, the -salary will be four hundred dollars per annum from the State of Maryland, and the privilege of taking thirty-five scholars, each of whom will pay twenty dollars a year for tuition. The trus- tees would state that few villages hold out more inducements for an academy than Rockville, The health of the place is not ex- celled by any in the State, and the society is as good as that of any village in the Union. The undersigned committee will receive applications for the situation of Principal until Wednesday, the 22d day of March next, when an examination and election will take place. It is expected that the Principal elect will enter upon his duties on Monday, the 17thof April. All applications must be accompa- nied with testimonials of character. JOSEPH II. JONES, ) JOHN COOK, Committee. SAMUEL C. VEIRS, P. S. Communications must be post paid. mitr 1-2aw4w AGENCY AT WASHINGTON.-JAMES H.CAUS TEN, (late of Baltimore,) having made this city his pernma- nentre.idence,andlocated hisdwellingandoffice directlyopposite to th e Department of State, will undertake, with his accustomed zeal and diligence,.the settlement of claims generally; and more particularly claims before Congress, against the United States, or the several Departments thereof, and before any board onf commissioners that may be raised for the adjustment of spo- liation or other claims. He has now in charge the entire class arising out oi French apoliations prior to the year 1800 ; with rererente to which, insaddition to a mass ofdocuments and proofs in hic, possession, he has access to those in the archives .f thle Government. Claimants and pensioners on the Navy fund, &c. bounty lands, return duties, &c. &c. and those requiriin life insurance, can hav their business promptly attended to by letter, (post paid,) ar d thus relieve themselves from an expensive and incon- venient personalattendance.. Having obtained ac commission of Notary Public, ihe is prepar- ed to furnish legalized copies of any required public documents or other papers. He has been so long engaged in the duties of an agent, that it can only be necessary now to say that economy and prompt intention shall be extended to all business confided to his care; and that, to enable him to render his services and facilities more efficacious, lie hlias become familiar with all the forms of office. teb 26-ly NAVY COMMiSSIONEi.ts' OFFrCE, MARCH 18, 1837. s L IVE OAK TIMBER.-Sealed proposals will be re- ceived at this office until three o'clock P. M. of the 1st day of July next, for the supply of Live Oak Titmher, as fol- lows : No. 1. For the frame timber, beam and keels-on pieces, and for the promiscuous timber which mny be directed, obr one ship of the line, one frigate, tvwo sloops of war, (one of .h1. 1. ., and onn e smaller vessel ; to be-delivered at the -,. A .',. near Portsmouth, N. H. No. 2. For the frame timber, beam and keel-on pieces, and for the promiscuous timber which may Ibe directed, for cne ship of the line, one frigate, and one steamer: tt. be delivered at the NVary Yard at Charlestown, Massachuscttls. No. 3. For the fame timber, beam and keelson pieces, and for the promiscuous timber which nmay be directed, for one ship of the line, one sloop, of war, large class, oe small vessel and one steamer: to be delivered atthe Navy Yard, Charlestown, Massachuisetls. No. 4. For the frame timber, beam and keelson pieces, and for the promiscuous timber which may be directed, for one ship of thie line, one frig ate, an one leamaier : to be delivered at thie Navy Yard, Brooklyn, V. Y. No. 5. For the frame timriber, beam and keelson pieces, and for the promiscuous timber which may be directed, for oneshipl of the line, one sloop of war, large class, and one sl eauer : toba delivered at the Navy Yard, Brooklyn, N. Y. No. 6. For the frame timber, beam and keelson pieces, and for the promiscuous timber Ihich nmay be directed, for two sloops of war, small class, and two steamers : to be delivered at time Navy Yard at Philadelphia. The quantity and dimensions of thIe promiscuous timber for each vessel, of each class, is as follows: For each ship of the linae 6,000 cubic feet; which must be sided 15 inches, and be from 12 to 20 feet in length, six of the longest pieces to side 22 inches. For each frigate 3,000 cubic feet; which must be sided 15 inches, and be from 12 to 20 feet long, six of the longest pieces to side 19 inches. For each sloop of.war 1,500 cubic feet; which must be sided 12 inches, aid be from 12 to IS feet long, six of the longest pie- ces to side 16 inches. For each steamer 1,,500 cubic feet; which must be sided 15 inches, and be from 12 to 18 feet long, six of the longest pieces to side 16 inches. For each small vessel S00 cubic feet; lwhicli must be sided 8 inches, and he from 10 oto 16 feet long, six of the longest pieces to side 121 inches. A part ofthe promiscuous timber may be got to larger dimen- sions, provided the pieces will answer for replacing defective hawse pieces, transoms, breast liooksd, or other valuable pieces. -Separate offers minust be made for each of lithe preceding nuntm- bers ad eich offer must embrace all lthe limber that is called for by the number to which it refers ; the prices asked per cu- bic foot must be stated separately for ach mind every class of vessels embraced in the offer, and for the promiscuous limber of each class separately from the other; all of which other is considered moulded timber. At least one-fourth of the whole quantity of timber embraced n each offer, comprising a fair proportion of the most valuable pieces, must be delivered on or before, thel last of March, 1839; one-halfof tlhe remainder on or before the last of March, 1340; and the whole quantity on or before the last of March, 1841; and if the above proportions shall not ba delivered at the respective times above specified, the Commissioners of the Navy reserve to themselves the right of cancelli:g any contract, in the execution of which such failure may occur, and of entering into new con- tracts, holding the original contractors and their sureties liable for any excess of cost, and other damages, which may be thus neurred. The said live oak timber'must have grown within twenty-five miles of the seabord, (which must be proven to time satisfaction if the respective Commandants,) must be got out by the moulds mnd written directions, and specifications of dimensions, &c. ,which witl be furnished to the contractors for their government, and must be free from all injuries and defects which unay impair the good quality of the sald timber for the purposes fur which it is required by contract, and be in all respects satisfactory to the Commandants of thie respective navy yards where it is deliv- ered. Bonds, with two good and responsible sureties (whose names must be forwarded with the offers) in the amount of one-third tho estimated value of the timber to be furnished under the res- pective contracts, will he required; and, as collateral security for the faithful compliance with the terms, stipulations, and con- ditions of thie said contracts, ten per centum will be reserved from the actual amount of edch payyment which may be made from time to time, within thirty days after bills shall bhdily ap- proved and presented to the Navy Agent, until the said con- racts are completed and closed ; which reservations, respect- vely, will be forfeited to the use and benefit of the United States, in the event of failures to deliver the timber within the respercive periods prescribed. The moulds will be furnished to the contractors at ,me of the navy yards, Brooklyn, Gosport, or Philadelphia. To be published twice a week, umtil the 151h of June next, in the National Intelligencei', Globe, Eastern Argus, New Hamp- shire Gazette, Boeton Morning Post and Commercial Gazette, New York Times, New York Evening Post, Trenton Empori- nm, Pennsylvanian, American Sentinel, Richmond Enquirer, Norfolk Herald, Raleigh Star, Charleston Patriot, Georgian, Pensacola Gazette, Louisiana Advertiser, and Mobile Register. mar 21-2awtl5J EW &S BEAUTIFUL BOOKS just received. The Pictorial Album, or Cabinet of Paintings ; containing eleven designs, executed in oil colors, by G. Baxtei ; some- thing new and very splendid. Harding's Port Folio, containing 24 splendid colored plates. Finden's Gallery of Graces, a series of 36 portrait illustra- tions, in style similar to the Beauties of Byron. For .-a!ce by GARRET ANDERSON, mar 22-3t Penn. avenue, between llth and 12th sts. N EW NOV ELS.-The Youthful Impostor, by G.W.M. Reyolds.i - Traits and Trials of'Early Life, by L. E. L. New supply of Pickwick Papers. This day received and for sale by GARRET ANDERSON, mar 22-3t Penn. avenue, between I tIh and. 12th sts. R. BIRD'S NEW NOVEL, Nick of the Woods, a Tale of Kentucky, in 2 vols. just published, and this day received, for sale by F. TAYLOR, or for circulation among the subscribers to the Waverly Circulating Library. Also, new edition of Henrietta T'1 mple. Life in Paris, or, The Rambles of Dick Wildfire, 2 vols. Delicate Attentions, and other Tales, by Paul Pry. mar 22 rjHE SUBSCRIBERS HAVE JUST RECEIV- ED- The Nick of the Woods, or the Jibbenainosay; a tale of Ken- tucky, by Dr. Bird ; in 2 vo!s. Godolphin, a novel, second edition. Traits and Trials of Early Life, by Miss Landon. The Youthful Impostor, by G. W. Reynolds. Life in Paris, or the Rambles and Sprers of Dick Wildfire. Paul Pry's Delicate Attentions, and other Tales. KENNEDY & ELLIOTT, mar 22-3t In the Athenmium. ft FOR RENT, the two-story Brick House in the vicinity of the City Hall, now in the occupancy oh" S Mr. John II. Noyes. The house is new and lately been handsomely papered, has a carriage-house and stable at- tached, and a neat yard with paved walks-rent$150. 'Pos-
session given immediately. Apply to
CHARLES II. WILTBERGER,
mar 16-eo6t City Hall.
W, HARF & WAREHOUSE FOR RENT.
S The subscriber wishes to rent his extensive Wharf
1 and Warehouse, on the Eastern Branch. It is well
calculated for the lumber, wood, coal, and grain business; like-
-wise for storing a large quantity of lime, there being ample ac-
commodation for the whole. The warehouse is two stories
high, 30 by 70 feet.
Any person wishing to go into the above business will doii,
well to examine the same. The rent will be made uncommon-
ly low. Possession may be had immediately.
mar 8-eo6w GRIFFITH COOMBE.
The Alexandria Gazette will please copy the above, and send
their account to G. C.
EDW NOVELS.-Just received from the publishers-
Nick of the Woods, or Jibbenainosay, a tale of Kentucky,
by the author of Calavar, the Infidel, &c.
Godolphin.
Life in Paris, or the Rambles and Sprees of Dick Wildfiroe and
others.
Paul Pry's Delicate Attentions, and other tales.
For sale at GARRET ANDERSON'S
Book, stationery, and fancystore, Penn. Avenue, between I Itli
and 12th streets. mar 22-3t
ENRIETTA TEMPLE, &c.-A new supply, with
The Fourth Way of Living-Living without Means, is
just received and for sale at
GARRET ANDERSON'S
Book, stationery, and fancy store, Penn. Avenue, between
1 lth and 12lh streets. mar 22-3t
"ULWER'S AND MAIRRYATT'S WORKS-
L Hansomely bound in one and two volumes.
For sale at GAlrRETr ANDERSON'S
Book stationery, and fancy store, Penn. Avenue, between
I lth and 12th streets. mnar 22-3t
4-1ENE.AL AUSTIN'S MAP OF1 TEXAS, by
c Tanner, just published, (l 83i7,) is Ithe largest and most
perfect and correct Map of Texas in existence. This dayy re-
ceived, and for sale by
Smart 22 P. TAYLOR.
SKETCHES 01F5 TIlE LIFE' AND CHARAC-
Sterinof time Rev. Lemuel Huynas, A. MI. by T. M. Cooley,
D.D. wihli Introductory Remaiks, by Win'X 1. Spragiue, D. D.
Pridau:x's Coinexions, 2 vols. with imaps and plates.
Srumuns of tlhe Rev. James Saurin, from the last Loud n edi-I
tion, containing one hundmredl Sermons.
Just received, and for sale by -
GARRET ANDERSON,
mar 8 Penn. Avenue, between llthanud 12th sts.
NOTICE TO CLAIMANTS
Under the act entitled An. act to carry into effect a Conven-
tion between the United States and Spain."
OrFFICE OF THE COMMISSIONERS (under the above act,)
Washington, February 8, 1837.
"lP1E Board; having considered and disposed of all the- mc-
morials before it,'lias passed ihe following Orders:
1. Ordered, That all persons having claims to be presented
to this Board, memorials for which have not been filed with the
Secretary, or which, being filed, have not been received by the
Board at its present session, by reason of defects in the same,
do file memorials of their said claims with the Secretary, on or
before the 22d day of May next; after which day no new me-
morial will be received, unless upon good cause shown why ihe
same was not filed, as heretofore required; and that each of the
said memorials, so required to be filed, be prepared and verified
in conformity to th -orders of this Board, of the 30th dayi'of
July, S136.
2. Ordered, That the memorials which have been received
by the Board at its present session be set down on the 22d day
of May next for examination, upon the proofs filed with the Se-
cretary previously to that period ; and that all memorials that
shall hereafter be presented and received by the Board, shall
be set down at the expiration of three months thereafter, (unless
good cause be shown to the contrary,) for examioalion.
3. Ordered, That in the case of every memorial in which the
clahimant intends to submit an argument to thie Board, such ar-
gument shall be fied with tie Secretary before or on the day
his memorial shall be set down for examination; and no proof,
argomenil, or other document shall be received after the memo-
rial is set down bor examination, except by special leave of the
Board ; and no paper sshill be withdrawn after being filed, with-
out such leave.
And, that time may be allowed to claimants to prepare and file
their memorials, ais above directed, procure their proofs, and
prepare their cases bfor examination, it is further
Ordered, That when the Board shall adjourn to-day, it will
adjourn to meet again on the 22d day of May next.
LOUIS 1). HIENRY, Commnissioner.
By JOHN I. MUMFORD, Secretary.
g_ The following are thOe DOrDrs of the 30th July, 1836,
to which reference is made above :
Notice to claimants under the act entitled An act to carry into
effect a Convention between the United States and Spain. -
The Commissioner under the above act having this day
adopted the following Orders, they are published for the infer-
mation of claimants:
Ordered, That all persons having claims under the Conven-
tion between the United States and Spain, concluded at Madrid
on the 17th day of February, 1834, which are to be received.
by the Board, do file a memorial of the same with the Secretary
of this Board, to the end that they may hereafter be duly ex-
amined, and the validity and amount thereof be decided upon
according to the merits of the several cases, and the suitable
and authentic testimony concerning them which may be furnish-
ed in support thereof. The said memorial must be addressed to
this Board; it must set forth minutely and particularly the va-
rious facts and circumstances whence the right to prefer
such claim is derived ; it must be verified by the affidavit of
the claimant.
Anud, in order to prevent unnecessary delay, and to expedite
the business of this Board, it is further
Ordered, That all the proof necessary and sufficient to sup-
port the respective claims aforesaid be filed with the Secretary
of the Board at the time of filing the respective memorials
thereof, or on or before the first Monday of December next, to
which day this Board will adjourn.
And, in order that claimants may be informed of what is now
considered by the Coommnissioner as essential to be averred and
established before any such memorial can be received by this
Board, it is further
Orde-ed, That each claimant shall declare, in his said me-
mnorial for and in behalf of whom the said' claim is-preferred, and
whether the amount thereof, and of any part thereof, if allowed,
does now, and at the time when the said chaim arose, did be-
long solely and absolutely to the said claimant, or to any other,
anid, if any other, what person ; and in cases ofclaimspreferred
for the benefit of any other than the claimant, the memorial to
be exhibited must further set forth when, why, and by what
means, and for what consideration, such other hlias become en-
titled to the amount, or any part of the amount, of said claim.
The memorial required to be exhibited by all claimants must
also set forth and certainly declare whether the claimant, as well
as any other for whose benefit the claim is preferred, is now,
and at the time when the said claim arose, was a citizen of the
United States of America; where lie is now, and at the time
the said claim arose was, domiciliated ; and, if any, whatchange
of domiciliation-has since taken place.
The said memorial minust also set forth whether the claimant,
or any other who may have been at any time entitled to the
amount claimed, or any part thereof, hath ever received any,
and, ifany, what sum of money, or other equivalent or indem-
nification, by way of insurance or otherwise, for loss or injury
sustained, satisfaction for which is therein asked ; and, if any
such paymnent-or indemnification has been made, to set forth
when and from whom time same wasxreceived.
LOUIS D. HENRY, Comnmissioner.
By JOHN I. MUMFORD, Secretary.
4 All communications relative to claims under the above act
must be addressed to the Secretary, at Washington.
mar 7-lawt'2dMay
W ENDELL'S DIGEST of Cases decided and re-
ported in the Supreme Court of Judicature, and in the
Court for the correction of Errors, in the State of New York,
from May, 1828, to May, 1835, with Tables of the names of the
Cases reported, and of Cases determined in thle Court for the
correction of Errors, from the commencement of the Reports
in the State of New York, until January, 1835, by John L.
Wendell, Counsellor at Law, in 1 volume, is just published,
'and this day received for sale by
feb 13 F. TAYLOR.
In Prince George's county Court, as a Court of
Equity-February Term, 1837.
Henry Mitchell,
Mary Ann Mitchell and others.
T HE object of this suit is to obtain a decree for the convey-
ance of part of a tract of land called Mitchell's Adven-
ture." The original bill states that a certain Tilghman Mit-
chell, being seized in fee of a tract of land called Mitchell's
Adventure, conveyed the same unto a certain Thomas L. Mit-
chell, with power to dispose of it for his benefit; that said land
was patented to Tilghman, and held by him individually ; that
Singleton Mitchell having defrayed one-half of the expensesof
said patent, a deed for his part vwas executed by thesaid Thomas
to tlie said Singleton, with the consent of the said Tilghman ; .and
that Singleton hath since conveyed the same to a certain Hen-
ry Mitchell; that Tilghman and Thomas have sold the balance
of said land to a certain Mary Ann Prather, formerly Butler,
and executed a bond of conveyance-to her for the same ; that
Rather and wife have assigned the said bond to a certain Lib-
burn Mitchell, who hath since transferred the same to the said
Henry Mitchell; that thie whole of the purchase minoney for tihe
same has been paid by the said Hilenry, excepting $100, with same interest for which the said Tilghman holds his single bill, and which he is ready to pay when he can obtain title to tihe said land. The supplemental bill e states te substance of the original bill, and also that an decree was passed by Prince George's county Court, at November term, 1836, against tihe said Tilghman, for the conveyance of said land ; that, before the said decree was rendered, the said Tilghman died, leaving the following heirs, to wit: Mary Ann, wife of the said Tilgh- man Mitchell, and Sarah Mitchell, Rebecca Mitchell, John Al- exander Mitchell, Maria Ellen Mitchell, and Thomas Morti- more Mitchell, minors under twenty-one years of age, and who reside in thie State of Ohio. It is thereupon ordered by Prince George's county Court, sitting as a Court of Equity, this 14th day of February, 1837, that the complainant, by causing a copy of this order to be inserted in some newspaper published in WVashitgton city once a week for four successive weeks before thie first Monday of April next, give notice to the said absent defendants, Mary Ann Mitchell, Sarah Mitchell, Rebecca Mit- chell, John Alexander Mitchell, Maria Ellen Mitchell, and Thomas Mortimorc Mitchell, of thie object and substance of the original and supplemental bill, and warn them to be and appear in this Court, in person or by guardian, on or before the second Monday in July next, to answer the premises, and show cause, if any they have, why a decree should not pass as prayed. EDMUND KEY. True copy-Test; A. BEALL, feb 21-w4w Clerk. A ARON BURR.-Just received, and for sale,-a newsup- ply of the Memoirs of Aaron Burr, by GARRET ANDERSON, Penn. Av. between 11th & 12thstreets. SPLENDID ENGLISH BOOKS.--List Conti- nued.-Just opened by F. TAYLOR- Middiman's Views in Great Britain, I vol. quarto. Life of Ali Pacha, illustrated with large colored plates, 1 vol. Major's Cabinet Gallery of Pictures of the First Masters of the English and Foreign Schools, 2 vols. filled with engravings, with remarks by Allan Cunningham. Stanfield's Coast Scenery of the British Channel. English Spy, 2 volumes, filled with colored engravings. Filtslhry's Holy Land, quarto engravings. Italian Scenery, 1 large folio volumno of plates. Nicholson on Masonry and Stone-cutting; plates. Splendid Albums, with engraving-. Naval Albumn, filled with nautical engravings. Merigot's Views and Ruins in Rome ; large quarto volume, with splendid colored engravings. Naturalist's Library, containing beautifully colored plates of various stilijects of natural history. All for sale unusually low. mir 3 In Chliarles CouniLty Court, August Term, 1836. N the matter of the petition of Leonard L. Robey and Delia, his wife, ad others, for the cvOision of the real estate whereof Edward Thomas died seized : Ordered by the Court that the return ofthecommnissioness in this case be ratified and confirm- ed, nless.causes to the contrary be shown by the third Monday in March next:a Provided a copy of this order he inserted in some newspaper published in the District of Columbia once in each of three suncessice weeks before the third Monday in March next, giving notice to the heirs absent out of the State of Maryland of this order. EDMUND KEY. True copy. Te l: JOHN BARNES, feb 25-w3w Clerk Charles County Court. EIGHT HUNDRED CORDS OF PINE WOOD. NAVY AGENT'S OFFICE, WASHINGTON, MARCH 18, 1837. 5 P ROPOSALS will be received at-this office until the Istday of May next, for eight hundred cords of Pine Wood, to be delivered at the Navy Yard in this city on or before the first day of October next. The wood must be well-seasoned and of good quality, and may be delivered from tiute to time as soon as the contractor may think proper to deliver it. Ten per centum will be withheld from the amount of each delivery until the contract is fully complied with, in addition to the bond and sureties given for the faithful performance of the contract. 8.'- To be published three times a week in the National Intel- ligencer, Globe, and Richmond Enquirer. mar 22 NAVY CommissoNErns' OFFICE, M ARCHe 23, 1837;. A SHI TIMBER.-Sealed proposals, endorsed Propo- sals for Ash Timber,",will be received at this office un- til 3 o'clock P.I I. o the first of May next, for furnishing at the Navy Yard, VWashington, (onehialf by tihe first of Decem- ber next, and the other half by the first of June, eighteen hun- dred and thirty-eight, or as much earlier as the contractor may choose,) twelve thousand cubic feet of' White Ash Timber, to be of the following dimensions, viz.. The whole to bu in logs of from twelve to eighteen feet in length ; one-fifth of the whole quantity to be sixteen inches diameter; one-fifth twenty inches; one-fifilhtwenty-six inches; one-fifth thirty inches ; and one-fifth thirty-six inches in di- ameter. The whole must be perfectly sound and free from all defects, suliject ito the inaspectionm and measurement of persons appointed by the cominandantof the yard, and in all respects to his entire satisfaction. Personas wishing to offer must offer for at least half the quan- tity, and state the price asked per cubic foot. Payments will be made within thirty days after the whole quantity ics delivered, and approved bills presented to the Navy Agent. Bonds, with two sureties in one-third-the estimated amount of the contract, will be required for its faithful performance. To be published twice a week till first of May next in the National Intelligencer, Globe, Army and Navy Chronicle, New York Times, Pennsylvanian, Baltimore Republican, Richmond Enquirer, and Norfolk Beacon. mar 25 -UALUABLE PROPERTY IN GEORGE-, I TOWN c-By virtue of a decree of the Circuit Court of the District of Columbia, made in the case of Edson & Scott against the administratrix and heirs at law of John Shaw, the subscriber will sell, at public auction, on Friday, the'28th day of April next, the following valuable real estate in Georgetown, and District of Columbia, viz. The large throo-story brick store and dwelling at the corner of Market Space and Cherry street, with the lot of ground on which it stands, measuring forty by forty-one feet, fronting on the south side of the canal. Attention is particularly invited to this property. Also, two handsome two-story brick dwellings, fronting on the east side of Potomac street, between Bridge and Prospect streets. They are quite new, and will be sold separately, with the ground attached. Also, a lot of ground at the southeast corner of Water street and Cecil alley, formerly the property of John McPherson, with the frame buildings thereon. All this property will be sold free of taxes and dower. The title is considered good. Terms of sale : One-fifth of the purchase money is to be paid in cash on the day of sale, or in five days thereafter ; the re- sidue in three equal instalments, at six, twelve, and eighteen months, with interest from the day of sale, the purchasers to give their bonds, with approved security, for said instalments. If the terms of sale be not complied with within ten days after the day of sale, the Tiustee reserves to himself the right to re- sell the property of the defaulting purchaser, at his risk and cost, after a reasonable notice. The sale will commence in front of the first mentioned house and house and lot, at 4 o'clock P. M. and continue from lotto lot until all has been sold. mar 23-3tawtds JOHN MARBURY, Trustee. E-UROPEAN AGENCY.-The undersigned intends to leave Pittsburg on the 1st day of March next, and sail from New York on thle 1st day of April, on an eighteenth tour through every part of England, Scotland, and Ireland, as a Gene ral Agent, for the purpose ofattending to such business as he may be desirous of transacting. He intends to return to Pitts- burg about the I st of December, 1837. The agents and friends ofthe subscriber, and the Public, are respectfully requested not to forward any documents or papers relating to any claims or business, until the same is first explain- ed and approved, after which, instructions will be given. Money-remittances made as usual to France, Holland, Ger- many, Switzerland, Italy, &c. &c. Every information connected with the Agency may be obtained, by post paid letters, address- ed to JAMES STUART, jan 5-eoc&d20t European Agent, Pittsburg, Pa. L LARGE MAP OF ILLINOIS-Nelwly publish- ed.-Engraved from the Government surveys, on a scale which covers six square feet, exhibiting the sections, &c. and pointing out the woodland, prairies, marshes, bottom lands, &c. &c. Also, the internal improvements, distance between towns, post offices, &c. &c. in a style of perfection and accuracy never attempted before with any of the Western States. Is just received and for sale by F. TAYLOR, in a portable form, for the pocket, at the Waverly Circulating Library, immedi- ately east of Gadsby's Hotel. jan 1 ANCIENT, MYSTERIES AND FREEMA- SONRY.-An exposition of the Religious Dogmas and Customs of the Ancient Egyptians, Pythagoreans, and Druids, &c. &c. Also, of the Origin, History, and Purport of Freemnat nrmy, by John Fellows, A. M. in one- volume, is just received, for sale by F. TAYLOR. mar 13 A AW OF PATENTS, by Willard Phillips, including L the remedies and legal procedings in relation to patent rights, in one volume, is just published, and this day received for sale by P. TAYLOR. HIS IS TO GIVE NOTICE that the subscriber lhas obtained from the Orphans' Court of Charles county, in the State of Maryland, letters of administration on the personal estate of Benedict Jameson, late of said county, deceased. All persons having claims against the said deceased are hereby warned to exhibit the same, with the proper vouchers thereof, to the subscriber on or before the first day of January, 1838; they may otherwise, by law, be excluded from all benefit of the said estate. Persons indebted to the estate are requested to make immedrliate paymentU WALTER F. BOARMAN, Executor, mar 17-wfiw Bryantown, Charles co. Md. SILESIAN BEET SEED.-A quantity of this genu- S ine Seed has been received from the Philadelphia Beet Sugar Society, together with the report of their agent, Mr. Ped- der. The former is foi-" sale at 75 cents the pint, the latter at 25 cents, by F. TAYLOR, who has been requested to under- take the sale of it in Washington city. An additional supply of Chaptal's Agricultural Chemistry is nst received. Also, Sir Hunphrey Davy's Agricultural Chemistry Porter on the Sugar Cane: A variety of works on the Silk-worm, the Mulberry, and the making of Silk ; also, on the Vine, and making of Wine. Secretary WVoodbury's work oi Cotton ; and a fine collection of the best works, generally, on Agriculture, Husbandry, Gar- dening, Botany, &c. &., in all their branches, mar 2 UPERIOR STATION ERY.-Thesubscriber has on S hand fomn recent purchases- 400 reams best American an d English Letter Paper 100 do Cap Paper 100 do Domi and Medium Paper 40 do Folio Post 100 do Envelope Paper C0,000 Quills 10 gross Inks in quart, pint, and hallf-pint bottles 200 pounds best American and English Sealing Wax 100 do Wafers 360 dozen Office Tape 500 cards most approved Steel Pens 20 gross best Lead Pencils 500 pieces India Inka 24 dozen Mouth Glue 28 do Cut Glass Inks, for office use 800 pounds of superior Black Sand With an extensive assortment of Ivory Folders Letter Stamps, Wafer, Pounce, and Sand Boxes Paper Weights, Rulers Blotting, Tracing, and Drawing Paper And every other article in the Stationery line, all of which will be sold on better terms than articles of similar quality cat be obtained elsewhere. Orders promptly executed at Station- ers' Hall. W. FISCHER. N EW LAW BOOKS.-Sugden on Vendors, new edi- tion, improved and enlarged, 2 volumes in I ; Kent's Commentaries, new edition ; Chiitty on Bills, Sth edition, just pUblished ; Rtussell on Crimes, just published ; Fontblanque's Equity, 4th editions; Wendell's Digest of New York Repo ts; Bland's Chancery Reports, 1836 ; Story's Equity ; Rosroe on Criminal Evidence ; Starkie on Evidence, 1837 ; Beck's Me- dical Jurispruidence, new edition, 2 vols. ; Williams's Medical Jurisprudence, I vol. price 75 cents. The above are just unpacked, and for sale by F. TAYLOR, who offers for sale an extensive assortuient of Law Books at prices as low s they can be purchased for any where in the United States. Ils supply lihas been purchased, not from other booksellers or publishers, but chiefly at thie Northmern spring and fall trade sales, t the sme times ani arid prices with all the Northern bookselling-houses; and supposing that hlie can afford to sell at as liw an m advance .rs any one, the advertiser with great confidence invites a comparisonbetween his prices and tlosc of any city in thie United SuItes. lundivilduals wisl.in to pIurchase may sauve themselves some expense and risk of transportation, by examining into this point for themselves, before sending their orders to the North. Ap- ply at the WIaverly Circulating Library, immediately east of Gadsby's Hotel. fel 16 , F ERESHI SPRING GOODS.-The subscriber having taken the store lately occupied by W. Stettinius, offers to til Public an entire fresh stock of seasonable Dry Goods, con- sisting in part as follows : Superfine Cloths, Cassimeres, and Cassinets Black Italian Lutestring, black and blue Poult de Sois Plaiuand figured Gro de Naps, Satins French worked Capes and Collars Thread Lace Edgings and Insertings Painted Muslins, Lawns, Shallietts, Ginghams and Calicoes Linen Cambrics, linen cambric, sea-grass and silk Hdkfs Fancy silk and gauze Handkerchiefs Blonde gauze Veils Dotted Thule, assorted colors, Bobbinets Fine French Bombasins, Irish Linens, Lawns Damask, Bird's-eye and RussiaDiaper, brown Holland Cambric, book and Swiss Muslins, Bishop's Lawns, &c. Silk and cotton Hosiery Ladies' and gentlemen s kid, silk, thread, and cotton Gloves Domestic, bleached, and brown do With a great variety of other articles, to which he would in- vite the attention of the Public, as they will he sold unusually low. ALSO. 2 cases plain Straw Bonnets 2 do Grecian do do 2 do Tuscan do 2 do Rolio do 2 do misses' Tuscan de 3 do fancy do mar 10-eolOt A. W. TURNER. 7 THE subscribers hlive received and are now opening their Spring stock of BOOTS, SHOES, &c. among which are the following, viz. 1000 pairs Ladies' black morocco and kid Slippers, 1000 do do seal do 1000 do do do Walking Shoes, 1000 do common, sewed, and pegged welted, 5000 do.Misses' morocco, kid, and seal Slippers,! 500 do do do Boots, 5000 do Children's morocco, kid & seal Boots & Ankle Ties, 500 tdo Infants' kid, 3000 do Gentlemen s calf, morocco, and seal, sewed, pegged, and nailed Boots, 2000 do calf and seal Bootees, .1000 do Unions and Van Burens, 1000 do Jackson Ties, 2000 do kip and split Brogans, 2000 do coarse Brogans, 1000 do Boys' pegged Bootees, 2000 do Youths' do 1000 do Men's fine seal heel Pumps 1000 do do spring heel Pumps. ALSO, 100 dozen prime French Calf Skinls, 100 do do Morocco, 50 do do Kid, 100 do Philadelphia Morocco and Kid, 200 sides Covering Leather for Coachmakers, 100 do Patent Leather do 200 do fine grain do do 100 do handsome Light Skirting. We shall be receiving, every week through the season, fresh stock from the manufacturers, all of which has been selected by ourselves, and bought on terms that will enable us to sell as low as any other house south of Boston. SW. NOYES & CO. 7th street, opposite National Intelligencer office. mar 8-coS't " OR SALE, two valuable house and kitchen Female Al Servants, one thirty-eight, the other fifteen years of age. Also, two Boys, one eleven, the other six years of age. The above servants will be sold for term of years. They are sprightly and intelligent, and also of a good complexion. They are perfectly honest, nothing inducing me to sell but that of my intention to go West. Also, the House and Lot now occupied by me will be sold very cheap. RICHARD H. DAY, mar 16-eo2w Bladensburg, Md. A TEACHER WANTED.-We wish to engage a young man who is well qualified to teaeh the Latin and Greek languages; also, all the other branches of an English education. One who can come well recommended can obtain a situation. We wish him to take charge of the school about the 1st day of April, and we are willing to pay a fair compensa- tion for the services of one that will suit. The number of scho- lars will be from sixteen to twenty. Letters addressed to either of the undersigned will be an- swered immediately. WILLIAM STEPHENSON, JAMES G. FICKLEN, feb 28-2awtf Near Winchester, Va. EISTE'S SLIPPERS.-A..W. TURNER has this day received- 200 pairs Este's French Morocco Slippers at$1 50
300 do McMullin's Kid and Morocco do at 81 25
200 do Misses' do do do do at $1 00 1000 do Women's Seal and Morocco Jefferson and do at 61. With a general assortment of children's and other Shoes. mar 20-eo5t A. W. TURNER. ]ILK HOSIERY.-We have this day opened our fresh importation of Hosiery. 50 blue-black English silk Hose 50 jet do do do 50 white silk do 50 black raw silk do 50 black English Hose 50 gentlemen's black raw silk do. ALSO. 40 dozen gentlemen's best kid Gloves 40 do do silk do 100 do ladies' superfine kid do 1 case very rich figured Silks. mar 14-3-taw3w BRADLEY & CATLETT. -RS. TYTE, from London begs to acquainttlhe vi- .v- sisters and residents of Washington, that she has just ar- rived with an elegant assortment of the newest and most FASH- IONABLE MILLINERY, consisting of Bonnets, Head Dress- es, Caps, Flowers, Feathers, &c., which are opened for sale, on Pennsylvania Avenue, between Ninth and Tenth streets, one doorjrom Varnum's Row. Il- Straws and Leghorns cleaned and altered to the newest fashions. dec 20-eotf -EGROES FOR SALE.-The subscriber has four L-likely young Negroes, which he wishes to sell for a term of years, viz. one girl, 18 years of age next June ; one boy, 15 in July next; one ditto, 13 in June next, and one other boy, 10 years old in November next. They are all negroes of good qualities, and are not to be sold for any fault. Any one wishing to purchase such will do well to call at the subscriber's residence, four miles from Washington,. on the south of the turnpike road leading to Bladensburg, where they may be seen at any time. mar 15-eo2w JOHN VEITCH. - ALEXANDER, TUpolsterer & Paper Hanger, qj. respeetfuly informs his friends and the Public generally that he has just received his Spring' assortment of PAPER HANGINGS, consisting of 2000 pieces of paper of the latest pattern and newest style, with velvet and common borders, as- sorted. Besides his stock, he has also a very handsome assort- mnent of Gildings and Cornices of every description, Beds, Mattresses, Pillows, Bolsters, Cots, &c. &c. Every order in his line will be attended to immediately. The whole of it will be sold cheap for cash, or on time to punctual customers. Two Apprentice Boys in the above line wanted immediate- ly. No one need apply without g-od recommendations. mar 9-eoIlm CITIZENS AND STRANGERS.-W. FISCHER respectfully invites the Citizens and Strangers to call at Stationers' Hall and examine one of (Messrs. Chickering & Co. of Boston) the most elegant and best Piano Fortes ever offered for sale in the District. The price for it is$525. Packed free
of cost. (Tel) mar 8-
CHEAP LEIPSIC EDITIONS of the GREEK
and Latin Classics, in the original.-P. TAYLOR
has just imported a large addition to his former collection of
classics, making his collection of this class oif literature much
more extensive and complete than is to be found generally in
the bookstores of this country.
The following comprise only a part of the collection, which is
sold as low in all cases as they can be found any where in this
country.
Florus, Dio Cassius, 4vols. Appiani Opera, 4 vols.
Theophrastus, Herodianus, Polybius, 4 vols.
Palingenii Zodiacus, Pomponius, Pliny, 5 vols.
Velleius, Aurelius Victor, JEschinis, Marcus Antonius
Justinian, Arriani Anabasis, Anacreon
Corpus Fabularum, Isaeus, Plato, 8 vols.
Aristotle, 16 vols. Dinysius, (of Halicarnassus,) 6 vols.
Plutarchi Moralia, 6 vols. Diodorus Siculus, 6 vols.
Demosthenes, 5 vols. Seneca, 5 vols.
Diogenis Laertii, 2 vols.
Qdintus Tryphiodorus Izetzes et Colvth, Apollodonrs
Curtius, Fabulie ]Esopoicnv, Gnoomici, Lucretius
Eutropius, Isocrates, 2 vols.
Phaiedri, Aviani, nt Faerni Fabule, Apolloniua, Lysias
)Elianus, Parsanius, 3 vols. Lncian, 4 vols.
Strabo, 3 vols. Isocrates, 2 vols.
Erasmus, 2 vols. Virgil, Sophocles
Sallust, Cornelius Nepos, Demoslhenes, 5 vols.
Thucydides, 2 vols. Homer, 4 vols. Livy, 6 vols.
Cicero 10 vols. Euripides, 4 vols. Ovid, 3 vols.
Juvenal and Persius,Phimdrus, Horace, Xenophon, &c.
-'I'The Leipsic editions are noted as being the most correct
editions of the classics extant, fob 28
F OR RENT.-The south part of Hlouse and Lot, as now
divided, at the corner of Maryland avenue and Twelfth
street west, containing five rooms and passage, a fine cellar,
also a kitchen, with three rooms, and separate stairway. The
hose is in good order, and has a large back yard and stable
attached to hlie premises. Possession can be had immediately.
For particulars, inquire of Mr. R. M. Bell, living adjoining, or
Edward Mattingly, near the Navy Yard.
mar 18-w3w
BALTIMORE LIFE INSURANCE COMPANY.
JOHN J. DONALDSON, PRESIDENT,
NSURES LIVES for one or more years, or for life.
----
Rates for One Hundred Dollars.
Age. One year. Seven years. For life.
25 1.00 1.12 2.04
30 1.31 1.36 2.36
35 1.36 1.53 %.75
40 1.09 1.83 3.20
45 1.91 1.96 3.73
50 1.96 2.09 4.60
55 2.32 3.21 5.78
60 4.35 4.91 7.00
GRANTS ANNUITIES.
Rates for One Hundred Dollars.
60 years of age, 10.55 per cent. )
65 do. 12.27 do. per annum.
70 do. 14.19 do.
SELLS ENDOWMENTS.
For One Hundred Dollars deposited at birth of child, the Coinm-
pany will pay, if he attain 21 years ofage, $469 At six months, 408 One year, 375 The Company also executes trusts; receives money on depo- site, paying interest semi-annually, or compounding it and inmakes all kinds of contracts in which life or the interest of mo- ney is involved. WILLIAM MURDOCK, Secretary. AGENTS. Jaies H. Causten, City of Washington. Dr. B. R. Wellford, Fredericksburg, Virginia. John 0. Lay, Richmond, Va. D. Robertson, Norfolk, Va. A. S. Tidball, Winchester, Va. George Richards, Leesburg, Va. Neilson PFee, Frederick, Md. feb 3-ly American Life Insurance and Trust Company. OFFICES-No. 136 Baltimore street, Baltimore; and Wall Street, New York. AGENCY-Pennsylvania Avenue, opposite Fuller's Hotel, anc two doors from the Buildings occupied by the Treasury Depart. ment, Washington city. CAPITAL PAID IN$2,000,000.
PATRICK MACAULAY, President, Baltimore.
MORRIS ROBINSON, Vice President, New York.
ONEY received daily on deposit, on which interest wili
be allowed, payable semi-annually. The Company ais(
insures lives, grants annuities, sells endowments, and executed
t rusts
Of the rdtes of insurance qf $100 on a single life. ANNUAL PREMIUM. Age. I year. years. For life. Age. 1 year. 7 years. For life. 14 72 86 1 53 38 1 48 1 70 3 05 15 77 88 1 56 39 1.57 1 76 3 11 16 84 90 1 62 40 1 69 1 83 3 20 17 86 91 1 65 41 1 78 1 88 3 31 18 89 92 1 69 42 1 85 1 89 3 40 19 90 94 1 73 43 1 89 1.92 3 51 20 91 95 1 77 44 1 90 1 94 3 63 21 92 97 1 82 45 1 91 1 96 3 73 22 94 99 1 88 46 1 92 1 98 3 87 23 97 1 03 1 93 47 1 93 1 99 4 01 24 99 1 07 1 98 48 1,94 2 02 4 17 25 1 00 1 12 2 04 49 1 95 2 04 4 49 26 1 07 1 17 2 11 50 1 96 2 09 4 60 27 1 12 1 23 2 17 51 1 97 2 20 4 75 28 1 20 1 28 2 24 52 2 02 2 37 4 90 29 1 28 1 35 2 31 53 2 10 2 59 5 24 30 1 31 1 36 2 36 54 2 18 2 89 5 49 31 1 32 1 42 2 43 55 2 32 3 21 5 78 32 1 33 1 46 2 50 56 2 47 3 56 6 05 33 1 34 1 48 2 57 57 2 70 4 20 6 27 34 1 35 1 50 2 64 58 3 14 4 31 6 50 35 1 36 1 53 2 75 59 3 67 4 63 6 75 36 1 39 1 57 2 81 60 4 35 4 91 7 00 37 1 43 1 63 2 90 Applications, post paid, may be addressed to- PATRICK MACAULAY, Esq., President, Baltimore; or MORRIS RO- BINSON, Esq., Vice President, New York; to which ihume- diale attention will he paid. Applications may also be madepersonally, or by letter, post paid, to FRANCIS A. DICKINS, Agent for the Company in the City of WASHINGTON. His office is on Pennvslvania Avenue, opposite Fuller's Hotel, and two doors from the buildings occu- pied by the Treasury Department. oct 16-26-dly HISTORY OF THE INDIANS of the Ameri- can Continent, in one octave volume, published by the American Antiquarian Society, is this day received for sale by F. TAYLOR. feb 22 USKISSON'S SPEECHES, in 1 volume, oc- tavo, containing also the Select Speeches of the Right Honorable WILLIAM WYNDHAM, together with their Biogra- phies, &c. &c. just published, and this day received for sale'by F TAYLOR. feb 15 EW BOOKS.-Just received, Life in London; or, The Day and Night Scenes of Jerry Hawthorn and others, in their Rambles and Sprees through the Metropolis, by P. Egan. The Honey Moon, by the Countess of Blessington, and other Tales by other authors. The Humorist, by Theodore Hook. For sale by GARRET ANDERSON, mar 10-3t Penn. Avenue, between 11th and 12th sts. fAEAUTIFUL BOOKS.-Now opening at Stationers' Hall the following beautiful Books, suitable for Christmas and new year's presents: The Souvenir Keepsake for 1837 The Religious Souvenir do The Pearl do The Violet do .The Christmas Box do The Gift do The Forget Me Not do Friendship's Offering do With a variety of Toy Books for children, and Almanacs for 1837, at 61 cents. W. FISCHER. dec 23 [Tel] N EW BOOKS.-Just published, and this day received, S for sale by F. TAYLOR, or for circulation among the subscribers to the Waverly Circulating Library- Life in London; or, Day and Night Rambles and Sprees through the Metropolis, 2 vols. The Honey Moon, and other Tales, by James Bulwer,.D'Is- raeli, and others, 2 vols. The T Humorist, in 1 yol. by Htook. FT HE BOOK OF SAINT NICHOLAS, translated fronmthe original Dutch of Dominie Nicholas (Egidius Ou- den Arde, by Paulding. For sale by GARRET ANDERSON, mar 10-3t Penn. Avenue, between I th and 12th sts. C ARD CASES.-Just opening, at Stationers' Hall, the largest and most extensive assortment of English Pearl, Ivory, Shell, and Leather Card Cases that has ever been kept for sale in the District, and at lnprices the most reasonable. jan 9 [Tel] W. P1SCHER. OOPER'S NEW WORK, Gleanings in Eu- rope, justreceived and for sale by F. TAYLOR. Also, Sketches of Every-day Life and Every-day People, by Boz, author of Pickwick Club, &c. _Minor Morals for Young People, illustrated in tales and travels, by John Bowning. mar 15 FANNING'S VOYAGES TO THE SOUTH SEA, containing, also, information relating to important late discoveries between 1792 and the present time. 1 volume octavo, with engravings. A few copies of the above publication (particularly interest- ing at the present time) are this day received, and for sale by feb 8 TAYLOR. ATVAW GLOSSARY, containing the Greek, Latin, Sax- on, Norman, French, and Italian sentences, phrases, and maxims, found in the works of Coke, Peere, Williams, Vesey, Rent, Sugden, Preston, Chlitty, Starkie, Bosanquet, Blackstone, Tidd, and numerous other law writers, with Historical and Ex- planatory Notes, alphabetically arranged, and translated into English for the use of Lawyers, Studenats, &c., is for sale by P. TAYLOR, 1 octavo volume, in law binding, over 500 pages, price$3 25.
Oliver's Law Summary, 1 octavo volume, lawyhinding, price
$1 75. Wentwomith on Executors, do do price 82 00. Supreme Court of the United States Reports for the term commencing January, 1834. Price$3 50.
Chittyon Bills, lasted.ilion, price \$1 75.
An extensive collectiofi of Law Books, alnil the latest and best
editions, are for sale at the Waverly Circulating Library, imme-
diately east of Gadsby's Hotel, in all cases at the lowest Phila-
delphia prices. feb 17
HEAP LAW BOOKS.-
Kent's Commentaries, Starkie on Evidence
Story's do Thomas's Coke
Chitty on Bills, Chmitty's Criminal Law
Do on Contracts, Norris's Peake, Ruterford's nstitte
Story on Bailments, Vattel's Law of Nttions
Cox's Digest, Cruise's Digest
Sugden on Vendors, Roscoe on Evidence
Comyn eta Coniracts, Fearoo on Remaeic[n.es
Fell on Gmaranty, Fomplanque's Equity"
Sugden on Powers
Diplomatic Correspondence of the United Stantes, from
!0th Sept. 1783, to March 4th, 1789, in 7 vols.
For sale by GARRET ANDERSON,
feb 28 At P. Thompson's old stand.
T HE GREAT METROPOLIS, by the author of
Random Recollections of the Houses of Lords andt.C0om1
nmons.-An additional supply of the above popular work is this
day opened and for sale by ,i 1. TAYLOR.
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https://quics.umd.edu/research/publications?page=29&s=author&%3Bf%5Bag%5D=N&%3Bf%5Bauthor%5D=1721&o=asc&f%5Bauthor%5D=93 | # Publications
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, Universal simulation of Hamiltonian dynamics for qudits, Physical Review A, vol. 66, no. 2, 2002. | {"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8452237844467163, "perplexity": 9053.903036158346}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2021-25/segments/1623487626008.14/warc/CC-MAIN-20210616190205-20210616220205-00275.warc.gz"} |
https://krymarh.wordpress.com/author/krymarh/ | # The Prince and the Pauper and The Theory of Mind
June 2, 2017
The last 25 chapters of The Reading Mastery V Textbook present an abridged version of The Prince and the Pauper. Since I don’t remember the original text, I am not sure how much more complicated or longer the original is. However, I don’t find the textbook version simple. It must be specially difficult for a person with autism. The person whose ability to take into account how the perception of things varies from reality seems to be limited. It is difficult to explain trepidation Tom Canty and Edward Tudor had to feel while being thrust into each other life. It is even harder to make sense of other characters treating Tom as if he were Prince Edward and treating Edward Tudor as if he were the poor boy from Pudding Lane.
June 21, 2017
On June 16, Robert finished reading The Prince and the Pauper. His dad accompanied him in this endeavor and later completed with him three pages of related worksheets. I regret that I was too tired to read with Robert that last chapter because I wanted to see Robert reaction to the ending. However, reading this text was extremely challenging. Maybe more challenging for me than for Robert. First, I had difficult time reading the parts that related to cruel mistreatment of Edward and his companion, Miles Hendon. I wasn’t sure if I should explain the cruelty of those times. I felt very uneasy reading about betrayals, flogging, begging, and all kinds of punishments mentioned in the book. I felt even worse knowing that Robert is reading as well. What pictures were created in his mind? What emotions were evoked? Would they stay with him or evaporate at the end of the chapter?
Over and over I kept remaining Robert that Tom Canty was treated like a king. The people in the palace believed that he was the king. Their beliefs were based on the way Tom was dressed. At first Tom protested but since his denials didn’t work, he decided to pretend to be the king. So he began to act like one. Edward, however, strongly and stubbornly kept behaving like Tudor, he was. Although he was confronted by people’s beliefs that he was a poor boy from Pudding Lane, he refused to act like one. Not only he didn’t beg and didn’t steal but he also made Miles Hendon a knight and, later, an earl. He would avoid mockery and mistreatment if he pretended to be Tom Canty, or at least stopped demanding to be treated like royalty. Yet, he constantly demanded to be recognized as a prince and then as a king. He didn’t adjust his behavior to match the expectations of those who formed false beliefs of who he was based on his tattered clothes.
Those are not easy concepts to grasp. I struggled with explaining the plot and struggled even more trying to figure out what Robert understood and HOW he understood it.
From the way, Robert answered questions in the worksheets, I should deduce that the complexities of the situations the boys put themselves in were not lost on him. He answered correctly. Still, I had doubts regarding Robert’s comprehension of the whole story. After all, Robert cannot explain anything with full sentences, The best I can count on are one word answers.
# So Puzzling, So Easy. Learning Elements of Algebra
May 3, 2017
$\frac{1}{3}x^3$
There are many aspects of Elements of Basic Algebra B written by Nancy Nichols and published by Firelight Books LLC, I don’t like. As I am using this workbook/textbook with Robert not once I find slightly incorrect statements. Not once, I think that some concepts could be introduced differently. Not once I think that I would present some of the ideas in a simpler, clearer way.
BUT
The truth is, I wouldn’t. I wouldn’t dare.
I wouldn’t have courage to teach Robert Algebra. I would consider it too sophisticated, too complex, and too abstract. I would be afraid of failing to teach him and confronting the limits of his abilities.
So although there are many things I don’t like about this curriculum, nonetheless, I am sticking to it because it presents elements of Algebra in the easiest possible way. In the way that shows how to introduce such concepts as “slope” or “y intercept” and then use them to present graphically linear equations.
No need to plug in numbers and perform operations on integers which are still relatively confusing to Robert. It is enough to look at the equation y= ax+b and plot the intercept (0, b) and then go a units up or down depending on the sign and one unit to the right remembering that slope = rise/run. That has been explained on many pages of the workbook with both positive and negative a and b.
April 6, 2017
For three months now, Robert and I have been reading story after story from old Reading Mastery V Rainbow Edition Textbook. This out of print SRA reading curriculum that includes Skillbook and Workbook, two Presentation Books and a few additional books had been waiting on a shelf for a few years before I dared to introduce it to Robert. I doubted Robert’s ability to understand the stories. I also distrusted my ability to guide Robert through reading in a way that would enrich his life.
To put it simply, I was afraid of his and my failures.
I didn’t know if Robert was armed in prerequisite skills that would make it easier to take a plunge into this program. After all, I didn’t work with Robert on any of the lower level curricula. We didn’t have Reading Mastery IV or III or any other. They were too expensive to purchase. The one in our possession was bought in a second hand store for a fraction of the original price.
Moreover, I felt intimidated by different approaches to reading comprehension. I read The Power of Retelling and The magic of Story. They described very sound methods and yet I knew that it would be almost impossible to use them with Robert. His ability to formulate sentences is so delayed that it renders him almost speechless. All too often, the deficiency of speech is misconstrued as the lack of ability to think and/or to understand. That happens specially when the reading instructor doesn’t have tools to asses student’s comprehension of a particular text.
Those were the reason I didn’t start Reading Mastery years ago. Meantime, we went twice through some of the texts in Horizon Reading to Learn. We completed a few of the Spectrum Reading workbooks. Some matched Robert’s developmental and personal needs, some didn’t.
Finally, I pulled the huge binder of the shelf, studied it for a while and presented the first story The Secret Cave to Robert. We analyzed the pictures that introduced the settings and characters. Then, I read a paragraph. Robert read the next one. The following paragraph, we read together. We kept switching until the end of the first part. Next, we worked on workbook and skillbook tasks that addressed comprehension in a few of its basic aspects. Mainly “WHO” “WHAT” and “WHERE” Less of “HOW ” and “WHY”, as those questions would require longer verbal utterances which would immediately discourage Robert from reading.
As we followed the textbook with The Wizard of OZ and other stories, I stopped using Presentation Book. Although that decision might have reduced Robert’s learning opportunities, it also simplified our reading process. So, we just read together and then answered the questions as they were presented in student’s materials. Some of them related to maps representing settings. Some of them asked which character said something or could have said something. Some asked if an event happened at the beginning or the end of the stories. It was easy for Robert to answer because he didn’t have to string words into complex sentences. It was reassuring to me because I finally had a tool to check some aspects of Robert’s comprehension and assert that yes, he grasps many elements of the story. He understands and /or remembers enough to let me go to the next story in the textbook or to the next event in our lives.
Since Robert’s language is delayed so severely that it interferes with expressing his thoughts, the options to answer in one word utterances to demonstrate his level of comprehension was rewarding to both of us. Finding the answer easy to say or write helped build his confidence. He didn’t have to struggle with multiple syllables which always came out scrambled beyond recognition. He could clearly say or write a word and be understood. And I could clearly recognize and appreciate his level of comprehension.
So we kept reading and enjoying it more and more with every new story.
It came to my attention that Reading Mastery Rainbow Edition differs in some aspects from Reading Mastery Signature Edition. For instance at least some of the stories in level V of an old edition are in level IV of a new edition.
# Horse for Prompt Dependency
February 13, 2017
In many of my previous posts I whined about Robert being too prompt dependent. I complained that as soon as I leave Robert alone with the worksheet, he stops working and waits for my return. I tried to make the tasks simpler. I went over the worksheets with Robert. After he answered every question orally I let him write down the answers he had just practiced. It didn’t help. I reduced the number of questions. It didn’t help. Every time, I left Robert alone with the problems he stopped working. He waited for me not to tell him the answer, but to encourage him with nothing more than, “Go on”.
It seemed that my words of encouragement were the switch that could turn on his brain. He would think when I asked him to think.
I realized that prompt dependency is not just the function of not knowing and waiting for someone to give an answer or to provide more or less subtle cue. It might be that some of the individuals are so prompt dependent that they delegate to others the right to operate the button that controls their engagement in the given activity. I realized that as I watched Robert trying to weave his horse, Calvin, between the cones. Robert has done that many times before. What was new, however, was that this time, his instructor Cindy was standing behind the rider and WAS NOT offering constant directions or words of encouragement. Moreover, Calvin was also reluctant to follow the path because he, too, needed constant reminders to continue. As soon as Robert lead the horse from left to right and right to left, the horse stopped. Calvin waited for a gentle nudge from Robert’s heels and the word, “Walk”. Robert, however, didn’t do anything as he was also waiting for Cindy to tell him, “Make the horse walk.” Cindy didn’t say anything. Since, she was standing behind him, Robert couldn’t even get a clue from her body language. So he waited. And waited. And waited. So Calvin waited. And waited. And waited. It seemed like a very long time passed before Robert nudged the horse and very softly said, “Walk”. Calvin weaved from left to right and from right to left and stopped again. Then Calvin waited for Robert and Robert waited for Cindy. But Cindy said nothing. Finally, Robert used his feet a couple of times to give Calvin a cue. Calvin moved again. From left to tight and right to left. This pattern of behaviors repeated itself one more time before the horse and the rider reached the end of the line of street cones.
It was an eye-opening experience for me. There were a few discoveries I made at the same time. They seemed almost too congested to pull them apart for clarity.
1. Robert needed a prompt almost in the same way Calvin needed a prompt.
2. At the beginning, Robert didn’t believe that he can control Calvin’s behavior the same way he let Cindy control his own actions.
3. Robert realized that he can control Calvin himself without being prompted to do so by someone else.
4. As Robert regained control of Calvin, he also reasserted the control of … himself. Robert gave command to Calvin AFTER he had given a command to himself.
I am not sure if Calvin was aware of the importance of this lesson for Robert. Cindy, however, was very aware. Just a few weeks before, we talked about Robert’s prompt dependency and she understood the nature of Robert’s problem much better than I. She knew how to design the lesson to convince Robert that he has to decide on his own what to do and that he has the ability to do so.
Of course, Calvin also helped.
Robert’s instructor, Cindy Conquest, sent me an e-mail with more detailed description of her approach. With her permission, I copied it below. It explains the steps involved in her teaching methodology.
“To give you a little background information if you have interest: I had to build up to get Robert do this gradually. I scaffold all of his lessons in this manner. In previous weeks, we started with the cue “walk around the barrel” and he would have to walk away from me 5 feet to get around the barrel, then turn to face me and come back to me. Sometimes Calvin would stop at the barrel, but as Robert turned around he would see my face and that prompted him to ask his horse to walk back to me.
Then we shifted to “walk to letter H (or any of the letters). I started out at the letters, then moved into Robert’s peripheral vision, then eventually moved behind him.
Finally, we graduated to the cones. Robert had completed the cone task many times with prompting, and Robert had successfully walked away from me many times by then withOUT prompting, so we combined the two. What was different this time was that it took Robert almost twice as long to initiate the task again once his horse stopped walking. However, he did initiate it. Others may consider this a “waste” of time as it appeared that Robert sat for at least a few minutes silently before he initiated the task. But, Robert finally did initiate the task on his own – which made all that waiting well worth the while. “
# Forcing Flexibility
February 11, 2017
Writing about Robert is like describing the ride on the rollercoaster. Before you find sentences depicting your slow mount to the top, you are already loosing your breath while sliding down with the speed that in a fraction of a second destroys all of your previously strung phrases turning them back into their gelatin beginning.
Not much has changed since, almost a year ago (February 23, 2016), I wrote the above sentences. There are calm times when Robert and I are learning. Robert is reading, answering questions, completing worksheets, speaking, solving problems. Slowly, with some difficulties we move from one concept to another. But before I write in this blog describing some of the idiosyncrasies that affect Robert’s appropriation of the specific ideas, something else happens, and I have to use all my resolve to steer Robert and us (his family) out of the path sharply descending into unknown. It might be that Robert wants our guests to leave and demonstrates his wishes in a way that cannot be accepted. It might be that Robert refuses to go to horse riding lesson with me but for hours keeps demanding that dad, who happens to be sick, takes him there. It might be that Robert insists that his dad stops working in the garden and returns to the computer. It would be so easy to give up. It would be much easier to tell the guests to end the visit. They would understand. It is much harder to make Robert accept their presence. It would be easier for dad, even when sick to get up and drive Robert to the horse riding lesson, than to teach Robert to accept that sick parent cannot always do what Robert wants. It would be easier to do garden work when Robert is not at home than to make Robert tolerate dad’s yard work.
It is much easier doing everything the same way since for Robert any change provokes his strong and long resistance. And yet we have learned that we have to do everything to make sure that Robert accepts different solutions or outcomes.
Years ago, Robert had to learn that different roads might still lead home. He wasn’t even three years old when we noticed that he always became agitated when on the way home, we took slight detour. He noticed immediately that it was a wrong way and acted up – kicking, wiggling in his seat and making noises. It took a lot of road constructions and detours before he understood that different roads might lead to the same place. Ability to adjust to change enlarges one’s world and frees a person from the rigid bars of rituals. Yes, Robert appears to feel safer when things remain the same. But, the things never remain the same forever. The change is inevitable. Robert cannot escape it. That is why we try to help Robert to adjust to the change or, sadly, show the consequences of not accepting it.
Those difficult moments often make me forget about calm hours of learning. But we still learn. Following old Reading Mastery V curriculum, we kept reading The Wizard of Oz. We solve problems – two pages a day from Singapore Math 4B . We build birdhouses or assemble 4 cylinder working toy engine. And we regain our serenity.
# Fait Acompli
February 9, 2017
It was exhausting. It was hard for my husband and for me. But it was excruciating for Robert. He was clearly in distress. Ignoring him didn’t help. Redirecting him didn’t help. So I did the only thing I could do. When Robert went to his dad again but without carrots, I took all the carrots out of the plastic bag and hid them. I left, however, the empty bag in the refrigerator.
Robert opened the refrigerator drawer and found an empty bag, threw it away, and …. went to watch Netflix on his IPAD. After four hours of attempts to force his dad to go with him to the horse riding class, Robert calmed down in a second. Just like that. He didn’t mention riding class not even once that day. Maybe for Robert there was no point of going horseback riding since not even one carrot left.
I left an empty bag because of my previous observations of Robert’s reactions. Many times in the past, when I tried to throw away his socks with holes, Robert would go through all the trash cans to find them and put them back in his dresser. When I, however, cut socks from top to bottom leaving a flat pieces of fabric and left them in the open, Robert accepted the fact that they couldn’t be worn anymore and dropped them in the garbage basket.
So I believed that hiding of the whole bag of carrot, would make Robert even more anxious. He doesn’t like when imperishable things vanish without explanation. Thus he would keep looking and persevering even more. Carrots, after all, could be eaten or used in cooking. Their disappearance could be explained and accepted to everybody’s relief.
# Rejecting Entropia
February 6, 2016
As soon as I drop dirty laundry into the hamper, Robert rushes to organize them in his way. He removes the clothes I have just dropped and places them back in the hamper one on top of the other in a the same pattern that he uses for his own garment. He places his clothes in the hamper in the same order he takes them off. The shirt is on the bottom, followed by the white undershirt. Next go his socks, jeans, and underwear. Every article of clothing is spread evenly. In the morning, he does the same thing with his pajamas. He changes pajamas everyday. Nothing would convince Robert to wear the same pajama two nights in a row.
When he suspects that either his dad or I messed up the clothes, he empties the whole hamper and meticulously places each item inside making sure that the order is followed. Day clothes, then night ones, day clothes, then night ones. My clothes are also placed in a proper sequence. And so are dad’s. Robert doesn’t rush. He takes time. He doesn’t make mistakes.
With similar attentiveness to the details, he places clothes in the washing machine and later in the drier. When doing so, he separates white garment from the dark, but nonetheless, keeps as much of the original order as possible. It is no wonder that Robert devotes a lot of his time to the laundry.
I have tried to explain to Robert that organizing dirty laundry is not important since the washing machine and the dryer would mix up all the clothes. I have told him that we could just drop the clothes randomly to the appliances and concentrate instead on folding and putting clean laundry in appropriate places. I have told him that many times, but Robert doesn’t accept randomness. Unrelentingly, he keeps on organizing each chaotic corner of the universe. One laundry basket at a time.
# Decoding, Enforcing, and Correcting Rules
February 5, 2017
Robert tries to find patterns in our chaotic movements and haphazardly performed everyday chores. If we repeat the same, meaningless behaviors a few times, Robert treats it as a paradigm of how we should behave every time. He insists that we follow the model he established for us based on his observations. We usually notice that when, for one reason or another, we abandon our insignificant routines and Robert becomes restless and tries to compel us to return to our convenient but senseless habits.
We know we cannot allow that, but all too often we are compliant with Robert’s wishes.
1. Robert wears his socks at home while I usually walk barefoot at home. So, when I had my socks on, Robert followed me all over the house. “Socks off, socks off” , he kept repeating. A few times, I took them off not really caring one way or another. Only when I noticed how distressed Robert became about my socks, I understood that we had a problem. So, to Robert’s dismay, I started wearing socks more often. Knowing, however, how persistent Robert can be, I developed a strategy that would give Robert an indication of how long I would keep them on. “Socks off, socks off” , insisted Robert. ” Oh, you want me to take socks off, I will do that when I finish this or that (usually short activity). “I will take them off when I get on the sofa to watch TV”. It took a while. But today, I can proudly say that Robert doesn’t care one way or another if I wear socks at home or not.
3. I used to drive Robert to his afternoon activities, but for the last few months it has been his dad who has taken him swimming and horseback riding. Everything went smoothly until one Sunday dad get sick and I needed to take Robert to his horse riding class. No way! Robert insisted that dad goes with him. Nothing seemed to persuade him otherwise. We had to cancel horseback riding class that day. And as of now we are still planning out next move.
# New Obstacles. New Frontiers. Part 1 Home, Home
February 2nd, 2017
Not so long ago, I had a notion that Robert’s behaviors would only get better. I thought that as he grows and learns, the problem behaviors we had dealt with in the past would vanish. I believed that acquired knowledge would result in better understanding of his environment and thus result in appropriate adjustment to new situations. I didn’t anticipate new kinds of issues. But they kept emerging. Some of them were created by Robert’s ideas about the rules controlling his world. The sources of other remain murky. Whatever their origins, the main cause of Robert’s problem behaviors remains the same. It is the lack of ability to communicate the causes of his distresses to others.
Robert used to like going out. He still does. He likes going skiing. He likes going on Saturday’s field trips organized by one of the centers. He loves SNL parties he can attend in another program. He wants to go to movies. Yet,in the last year in all of those and other places he expressed very loudly his desire to go home.
“Home, home”, he would call in the middle of the movie. “Home, home”, he demanded not even one hour into 2 hour-long ski lesson. “Home, home”, he insisted in the middle of the party. “Home, home, home” he would keep on saying using all kinds of voices, from a low one to a very dramatic high pitch.
It gets more complicated.
In the movie theater, for instance, Robert doesn’t want to leave before the movie is over. He wants to go home, but not before the ending. If I get up, and say, ” Let’s go”, he would equally loudly protest, “No, no, no!” . Because Robert wants the movie to end just that minute, so he could leave after finishing seeing it.
In the bowling alley, Robert would keep bringing regular shoes to his bowling companions, so they would stop playing, take off their bowling shoes, and leave so Robert could go home.
He can be extremely persistent. He can repeat “Home, home” ten times a minute, every minute for an hour or longer. This is not easy for him, and it is equally difficult for everybody else.
If this behavior happens during his swimming or skiing lesson, it is helpful to tell Robert that he would go home after completing some other activity. ” Robert’s swimming instructor, tells Robert that he would go home after swimming one or two more times(or three, depending on her assessment of his distress.) She moves her hand back and forth as many times as she wants Robert to swim. The skiing instructors use similar explanation although they might tell Robert, “First we go on this trail, next on that one, then you will go home.”
The most important thing, however, is NOT to interpret this behavior as a sign that Robert doesn’t want swimming, skiing, field trips, or going to movies and parties. It is possible that when he goes to a new place or the old place he hasn’t visited for a while, he feels confused of how long he should stay there and what to expect. So we kept going back with Robert. We tell him what to expect in this place and what is expected of him.
That is why Robert went to two other SNL parties and three other ski lessons. He did better, then he did great.
It is not, that I believe that Robert has already learned not to call “Home, home” in many new places, or the places he partially forgot and thus become confused and concerned. He might call, “Home, home” again, but that is not the end of the world, and it shouldn’t be something that would prevent him for coming back.
# Back to Writing a Journal, Page 17
January 12, 2017
One month has passed since my last post on this blog. We are still learning. We do a lot of ,so-called, “maintenance” by going over the same old topics that Robert encountered in the past. We review them through new worksheets or through the same ones we did years ago. Meantime, Robert and I completed all the lessons from Saxon Math 4 and from Horizon Reading to Learn C-D Fast Track. I won’t claim that Robert mastered those curricula, but he grasped a lot and became familiar with the rest.
We started with Saxon Math 5, but after a few lessons and multiple exercises I decided to review fourth grade topics by using Singapore Math 4B. US Edition which is a little simpler that the original one. Many topics in Singapore Math are presented in a clear format allowing for better grasp pf concepts. For instance rounding of decimals was introduced by drawing appropriate number lines. For instance to round 4.28 to the whole number Robert had in front of himself a segment with 4 and 5 at the end and 4.5 (or 4.50 ) in the middle. Number 4.28 was clearly between 4 and 4.5 so the choice was easy to make.
To round the same number to the tenth decimal place, Robert could use a segment with 4.2 and 4.3 at the ends which he improved by adding zeros at the end and thus having 4.20 and 4.30. He had already placed by the authors 4.25 in the middle and 4.28 on the right side of it, closer to 4.30.
That was exactly as we practiced before when Robert had to round large whole numbers. Except, it was Robert’s job to draw a line segment, write numbers at the ends and in the middle of a segment, and place the given number in the correct half. This process was never easy. For Robert the exercises which clearly placed all important number cues on the line segments seemed not just easy but also helpful in understanding better the concept behind rounding.
I am not sure, however, if the fact that we started with more difficult, but “hands on” approach that forced Robert to do all the steps by himself was not beneficial to his learning even if it wasn’t completely understood.
We continue doing speech and language exercises using worksheets from Speech Improvement Reproducible Master and the Fun Deck 4. They are easy because what is easy helps with fluency and reduces the stress Robert feels every time he has to speak.
While I was cleaning drawers I found old worksheets related to time telling and we did many exercises on finding elapsed time. That is a topic that is still difficult. However, I also found many exercises that seemed to be easy enough for Robert to do on his own. Some of them required doing math operations, some matching synonyms or antonyms. Leaving Robert alone for 15-20 minutes to do that work independently was very gratifying. | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 1, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.38529571890830994, "perplexity": 2402.9532941505636}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2017-26/segments/1498128320057.96/warc/CC-MAIN-20170623114917-20170623134917-00226.warc.gz"} |
https://physics.stackexchange.com/questions/169257/does-the-frac12mv2-law-apply-to-quantum-mechanics | # Does the $\frac12mv^2$ law apply to quantum mechanics?
Consider the classical Hamiltonian for a spring: $$H = \frac{1}{2}\frac{p^2}{m} + \frac{1}{2}kx^2$$ This is one of those simple cases where when you work out the math we find $$m\ddot{x} = -kx$$ and it makes plain and obvious that the $\frac{1}{2}\frac{p^2}{m}$ term has now turned into $m\ddot{x}$, Newton's law. So it's clear here how the $\frac{1}{2}\frac{p^2}{m}$ corresponds to the $m\ddot{x}$ term and the $-kx$ is consistent with Newtons law.
My Question:
Does this relationship between $\frac{1}{2}\frac{p^2}{m}$ and $m\ddot{x}$ hold for the quantum mechanical operator? By the operator, I mean this Hamiltonian
$$\hat{H} = \frac{1}{2}\frac{\hat{p}^2}{m} + \hat{V}$$
Its obviously the same format, but my suspicion is that it doesn't carry the same relationship to Newtons laws because of the fundamental differences between classical and quantum mechanics. If I am correct that the quantum mechanical operator is unrelated to Newton's law, can someone explain why given they are of the same format?
Yes, it holds referring to the Heisenberg evolution of operators and in the specific case of the harmonic oscillator: $$\hat{x}(t) := U(t)^\dagger \hat{x} U(t)$$ where $U(t) := e^{-it\hat{H}}$ (here $\hbar:=1$). One has $$\frac{d^2}{dt^2} \hat{x}(t) =\frac{d}{dt} \frac{d}{dt} U(t)^\dagger \hat{x} U(t) = \frac{d}{dt} U(t)^\dagger i [\hat{H}, \hat{x}] U(t) = U(t)^\dagger i^2 [\hat{H},[\hat{H}, \hat{x}]] U(t)\:.$$ Using the explicit form of $\hat{H}$ of the harmonic oscillator and the canonical commutation relations, $[\hat{x}, \hat{p}]= iI$, you have $[\hat{H},[\hat{H}, \hat{x}]]= \frac{k}{m}\hat{x}$ so that, $$U(t)^\dagger i^2 [\hat{H},[\hat{H}, \hat{x}]] U(t)= -\frac{k}{m} U(t)^\dagger \hat{x} U(t) = -\frac{k}{m} \hat{x}(t)$$ so that $$m\frac{d^2}{dt^2} \hat{x}(t) = -k \hat{x}(t)\:.$$ This result does not hold for more complicated forms of $V$ as you can see by direct inspection.
• Putting aside domain issues and regularity of the potential, it seems to me that the Hamilton equation $\dot p = -\nabla V$ holds in general in this approach, as $[\hat p,V(\hat q)] = -i\hbar \nabla V(\hat q)$, where $\nabla V(\hat q)$ is the "multiplication by $\nabla V$" operator. Am I overlooking something? – Phoenix87 Mar 9 '15 at 12:46
By Ehrenfest's theorem you have $$i\hbar\frac{\text d}{\text dt}E_\omega[q] = E_\omega[[q,H]]$$ and $$i\hbar\frac{\text d}{\text dt}E_\omega[p] = E_\omega[[p,H]]$$ where $E_\omega$ indicates the expectation value over the state $\omega$. Simple computations show that the first equation gives $$i\hbar\frac{\text d}{\text dt}E_\omega[q] = \frac{i\hbar}m E_\omega[p]$$ while the second one gives $$i\hbar\frac{\text d}{\text dt}E_\omega[p] = -i\hbar kE_\omega[q].$$ Setting $x:=E_\omega[q]$ and $\pi := E_\omega[p]$ you see that you get $$\dot x = \frac\pi m\qquad\text{and}\qquad\dot \pi = -kx,$$ whence $$m\ddot x = -kx.$$
More generally, given a generic potential $V$ which is differentiable, the above equations generalise to $$m\ddot x = -U',$$ where $U':=\frac i\hbar E_\omega[[p,V(q)]]$, which coincides with $V'(x)$ only when $V'$ is linear in its argument. | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 1, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 3, "x-ck12": 0, "texerror": 0, "math_score": 0.969140350818634, "perplexity": 93.97931248054039}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2019-47/segments/1573496670731.88/warc/CC-MAIN-20191121050543-20191121074543-00003.warc.gz"} |
https://wiki.minr.org/index.php?title=Updates&diff=prev&oldid=9035 | # Difference between revisions of "Updates"
A log of changes since the 10.0.0 Minr Scripts 2 + 1.13 update.
## Upcoming
11.0 - Everything And The Kitchen Sink (releasing sometime in 2020)
12.0 - Commands Overhaul
## 10.7 - Scripts 2.3
### 10.7.1 (2020/11/21)
#### Server Configuration
Logins with non-whitelisted mods will be rejected.
Signs and scripts are now clickable with left mouse button, even in adventure.
#### Scripts
Added boxing/unboxing (on the backend) to make maintaining builtin functions easier. Should not affect any of the behaviour.
### 10.7.0 (2020/11/12)
#### Scripts
Added new generic functions on List. Generic means that they can take any Type within constraints. In the following T will be the base type of your list (i.e., String[] -> T = String).
Void append(T value) appends a value to the List.
Void add(T value, Int index) places a value at an index, shifting the elements at that index and higher one index up.
T pop() removes the last element of the list and returns it.
T remove(Int index) removes the element at index from the list and returns it.
Boolean contains(T value) returns whether the list contains an element that equals value.
Int find(T value) returns the first index that matches the value. Throws a ElementNotFoundException if the value is not in the list. (Tip: always use contains before find)
Two functions have been added specifically for String[]:
String concat() concatenates a list of Strings together: String["hello", "world"].concat() yields "helloworld".
String join(String delimiter) joins a list of string, inserting delimiter between each string: String["hello", "world"].join(" ") yields "hello world".
## 10.6 - Scripts 2.2
Update to 1.16.4
### 10.6.10 (2020/10/28)
#### Scripts
Added traces to help find the cause of an exception in a Script. Only works for opped players.
#### Bugfixes
Fix NullPointerException on Materials that are Null.
Optimize script execution to reduce the chance of a StackOverflowError.
### 10.6.9 (2020/10/26)
#### Bugfixes
Actually store and load Material to/from file.
### 10.6.8 (2020/10/24)
#### Bugfixes
DiscordBot is now independent of discord server name, previously causing discord requests to fail due to the server name changing.
Any issues with deverification are now properly logged.
Fixed serialization of Position
### 10.6.7 (2020/10/13)
#### Bugfixes
Allow deverification even if Discord user can no longer be found.
### 10.6.6 (2020/10/11)
#### Bugfixes
Fixed /scripts copy and /scripts paste not working when pasting in a different world.
### 10.6.4 (2020/10/01)
#### Bugfixes
Re-calculate player display names on rank change.
Fix crash when calling toString() on a default Position variable (one without a value).
Fix calling toString() on a default Location variable returning 'null null null null' instead of 'null'.
Fix obj == null where obj is set to null or uninitialized not functioning properly.
### 10.6.3 (2020/09/23)
#### Bugfixes
Fix portal scaling when going from an overworld to a nether being 64:1 instead of 8:1.
### 10.6.1 (2020/08/29)
#### Hardcore
Bumped Hardcore version to 10.1.
Add 10.0 -> 10.1 Hardcore checkpoint conversion.
Add support for forcing a player to respawn at their Hardcore checkpoint upon conversion, even if it hasn't moved.
### 10.6.0 (2020/08/18)
#### Scripts
Position(Double x, Double y, Double z, Float yaw, Float pitch, String world)
Location(Double x, Double y, Double z, String world)
Vector3(Double x, Double y, Double z)
Vector2(Double x, Double z)
BlockLocation(Int x, Int y, Int z, String world)
BlockVector3(Int x, Int y, Int z)
BlockVector2(Int x, Int z)
Region(String id, String world, String type, X points, Boolean transient)
These all have methods, too innumerable to mention here.
See this forum post for a short overview.
Added Location player.getLocation(), Position player.getPosition() and BlockLocation block.getLocation().
Added Player.teleport(Position destination) and Entity.teleport(Position destination).
#### Commands
/prefix now shows <colour> when setting a prefix consisting of only a colour, i.e. /prefix set rickyboy320 10m &6
#### Chat
Player names are now stored in proper text components.
As a consequence, keeping the colon colour of player names in chat consistent with the name colour was disproportionately difficult, so it is now white. (i.e. rickyboy320: hello world).
## 10.5 - The Bakery
### 10.5.5 (2020/07/30)
#### Commands
Added /challenge modifier set <player> <modifier> <value> to set a player's modifier value mid-challenge.
Added /challenge modifier add <player> <modifier> <value> to add a value to a player's modifier (i.e. life challenge).
#### Bugfixes
Fixed @chatscript timeout resetting newer instances of the same group (even when the timeout shouldn't trigger).
Fixed an issue where sometimes a value would be rejected due to 'self-cycle', even though there was none.
### 10.5.4 (2020/07/24)
#### Scripts
Added Boolean util::executeAndQuerySuccess(String command) and Int util::executeAndQueryResult(String command).
Added String util::randomUUID() to randomly generate an UUID.
format::formatDate now uses a timezone of UTC, so you can use more formats.
### 10.5.3 (2020/07/24)
#### Server Configuration
Updated to 1.16.1.
### 10.5.2 (2020/07/06)
#### Privacy
Messages are now sent to the (private) #zero_archive channel as well, allowing for periodic wipes of the public #zero channel.
#### Bugfixes
Fixed a bug where certain player settings would not be saved if modifed while the player was offline (e.g. from discord).
Fix potential data loss if an error occurred during start up.
### 10.5.1 (2020/06/16)
#### Bugfixes
Fixed a bug where logout messages would show even when they were supposed to be hidden.
### 10.5.0 (2020/06/15)
#### Scripts
Scripts are no longer triggered while the player is in spectator mode.
#### Commands
/players now sorts by rank, and player names are now coloured by their rank.
Disabled certain functionality on the test server, for privacy and secrecy reasons. Greens will be unaffected by this.
#### Hardcore
Players now retain their Hardcore checkpoint at Hall of Fame (HC-END) on conversion, rather than being removed.
Players now are blocked from entering Hardcore if their Hardcore checkpoint is at Hall of Fame, or if they have no Hardcore checkpoint but have completed Jiga's Claymaze.
#### Chat
The format of player join and quit messages has been changed to match Vanilla (the exclamation point has been replaced with a full stop).
The player's rank is now displayed during first-time join messages.
First-time join messages will no longer be shown if they are not of default rank, even if they have no existing player data.
## 10.4 - Scripts 2.1
### 10.4.13 (2020/06/14)
#### Bugfixes
Fixed players being set to Blue on map complete if they satisified the blue requirements, regardless of their rank.
### 10.4.12 (2020/06/14)
#### Ranks
Blue now requires 100 points (up from 35).
Blue now requires at least 5 or more maps completed of Moderate or greater difficulty.
#### Hardcore
Incremented Hardcore version from 9.0 -> 10.0.
Implemented Hardcore checkpoint conversion for 9.0 -> 10.0.
Improved conversion of checkpoints from 7.0, 8.0 and 8.1.
#### Commands
Added /checkpoint remplayercp <player> <mode>, to remove a player's checkpoint.
Updated /help ranks to reflect the new blue requirements and better convery rank-up requirements.
### 10.4.11 (2020/06/05)
#### Bugfixes
Fixed array initializers of 2 or more elements failing to parse inline (as an argument for a function calls or within a subexpression).
Fixed 'silent' error when a script line containing a '%' contains an error.
Fixed pi being accepted as a variable name: it should have been a keyword.
Fixed error message saying 'missing right-side operator', while actually the left side was missing.
### 10.4.10 (2020/05/19)
#### Commands
/creative is now accessible by moderators.
/tps is now available for greens+.
#### Bugfixes
Fixed an issue where variables in a namespace A using a type from namespace B sometimes fail to load their fields. (If namespace A was loaded before namespace B).
### 10.4.9 (2020/05/14)
#### Maps
Global Points have been renamed to Speedrun Score in an effort to make the name more intuitive.
You may also call it Minr Clout. You know who you are.
#### Scripts
Added @fast and @slow script operators.
By default, the @command, @bypass or @console script operators have a one-tick delay (like @delay 1).
@fast will remove that delay for all subsequent command operators.
Having either one multiple times in a row without the other is legal.
Note that this effect only applies to the local execution context - other functions called will be unaffected.
Added player.getSpeedrunScore(). player.getGlobalPoints() is now deprecated.
### 10.4.8 (2020/05/02)
#### Challenges
Added the Monthly challenge, containing from 8 to 25 maps, to cycle every month. The reward calculation is done the same as dailies and weeklies.
#### Commands
Added /checkpoint uncompleted which shows the maps the player yet has to complete (excluding valley/HC/board maps).
#### Scripts
Added String Player.getBedLocationWorld(), which returns a String containing the world where the player has set their bed.
Added String[] String.split(String separator), which splits the string based on the separator into a list of pieces around the separator. For example: "hi world".split(" ") would yield: ["hi", "world"].
Added Double[] system::getTPS() which returns a list of size 3, containing the average TPS over the last 1 minute, 5 minutes and 15 minutes.
#### Bugfixes
Fixed nested @for loops erroneously failing to compile.
Fixed setting max health using player.setMaxHealth() resulting in errors when joining a map, setting a checkpoint and in other arbitrary scenarios.
Fixed the left-hand sides of a @var assignment incorrectly parsing if the target expression was a field of an array.
### 10.4.7 (2020/04/19)
#### Bugfixes
Fixed an issue where removal of food was not saved, if this was the only action on a map.
Fixed an issue where having multiple constructors for one type would result in only one of the constructors remaining after server restart.
### 10.4.6 (2020/04/12)
#### Bugfixes
Fixed an issue where Player variables were not loaded correctly (resulting in null).
#### Cosmetics
Hats
Added "Bunny" hat, which requires finding 10% of the eggs in the open world of Egghunt 2.0.
Added "Compeggitor" hat, which requires participating in the Egghunt 2.0 Compeggition.
Added "Golden Egg" hat, which requires finding 50% of the eggs in the open world of Egghunt 2.0.
Titles
Rebranded the title "The Eggman" to "The Egglord", now requiring the victory of any Egghunt Compeggition.
Added "Eggspert" title, which requires finding all the eggs in the open world of Egghunt 2.0.
### 10.4.5 (2020/04/04)
#### Challenges
/spawn is now allowed during challenges.
Players can no longer use the Hardcore start sign whilst in a challenge.
#### Commands
Removed /sethome <player>. Note other variations of this command are unaffected.
/listhomes <page> now has priority over /listhomes <player>.
#### Scripts
Added literals pi and π (both equal to 3.14159265358979323846)
Added the following functions to the math namespace:
sin(), cos(), tan()
arcsin(), arccos(), arctan()
deg()
#### Discord
Minr Bot will no longer use markdown in messages.
#### Bugfixes
Visiting another player's home would set the target player's checkpoint mode to home, instead of the executor's.
Fixed /checkpoint times <page> checking for map codes before map names.
Fixed Float/Double values with the literal xxxE-xxx failing to parse.
Fixed various commands that take namespaces requiring the same namespace specifier. (/variable define casino_lb DBtable db would fail even though DBtable is a type in casino_lb)
Fixed an issue where in some cases Int(someList[0]) (or similar) would fail to compile.
Fixed @for loops within a @if statement failing to execute in special cases.
Fixed @done not showing a parse-error when it was put on the wrong depth level.
### 10.4.4 (2020/02/21)
#### Bugfixes
Fixed paged commands' paging arrows failing to work.
### 10.4.3 (2020/02/11)
#### Commands
/home
Homes are now listed alphabetically and shown in pages.
Mods can now set homes using coordinates.
Ops can now set and remove others' homes.
/whois
whois <player> is now usable by everyone.
whois <player> is now usable on Discord.
### 10.4.2 (2020/01/10)
#### Bugfixes
Fixed 100% not being attainable, due to aliased maps counting twice to total points.
### 10.4.1 (2020/01/06)
#### Bugfixes
Fixed default values of relative variables not being loaded (and therefore being lost after a restart).
### 10.4.0 (2019/12/20) - Scripts 2.1
#### Scripts
Lists
They are automatically created for every non-list type.
Lists are defined using X[], where X[] is a list of type X (e.g. Int[]).
Lists can be initialised with X[a, b, ..., z]. (Where a, b, ..., z are zero, one, or more instances of X)
Values can be retrieved using X[index]; to set a value simply assign to this (e.g. X[0] = 1).
List indicies are zero-based.
To append to a list, simply assign a value to an index one greater than the last item in the list.
e.g., if @define Int[] x = Int[1, 2, 3], append to x with @var x[x.length()] = 4.
Accessing an out of bound index will yield an IndexOutOfBoundsException (which will terminate the script).
Lists have the following methods:
List.length(), which reports the number of items in the list.
List.remove(Int index), which removes the item at the specified index from the list.
List.clear(), which removes all items from the list.
List.reverse(), which reveres the order of the items in the list.
List.shuffle(), which will randomise the order of the items in the list.
List Namespace
A range() function was added to a new list namespace as a convenience.
Int[] range(Int start, Int end) will generate a list of numbers from start (inclusive) to end (exclusive).
This allows you to iterate through every index in a list with @for Int i in range(0, list.length())
Loops
Added for-in loops, to iterate over any iterable.
Lists are the only iterable at this time.
Loops are defined with @for X item in X[], and terminated with @done
This example loop will print 1, 2, 3, 4 and 5 to the player (on separate lines).
@for Int i in Int[1, 2, 3, 4, 5]
@player {{i}}
@done
To loop through a range of numbers (like for (int i = 0; i < 10; i++)), use list::range().
@for Int i in range(0, 10)
Relative Variables
It is now possible to retrieve the value of a relative variable for specific players.
Simply use relativeVar[Player]. (Where Player is an instance of a Player type: e.g., Player("rickyboy320"))
Note that as this requires a Player instance, UUIDs will be required for retrieving values when players are offline. (Will fail otherwise)
Like lists, assigning to relativeVar[Player] will set their value.
Formatting
Whitespace will now be preserved when importing from Hastebin, and will be exported as well.
Script Creation
When creating a script, the co-ordinates of the script will be displayed. If you accidentally misplace a script this will allow you to easily remove the script.
Math Namespace
Added Int floor(Double x) and Int ceil(Double x), which floor and ceiling a number respectively.
Player Type
Added sendMessage(String message) to send a raw message directly to a player.
#### Commands
Added /challenge join <challenge> <player> and /challenge finish <challenge> <player> for administrators.
Fixed /checkpoint removealltimes not working on maps.
#### Discord
/discord verify now correctly instructs the player to post their verification code in #verify_here, instead of #general_discussion.
#### Server Configuration
Updated to 1.15.1 (Paper #15)
#### Bugfixes
Fixed c_dric's bug, where setting a field would spawn multiple script runners (causing delays to be skipped).
Fixed tab-completion of namespaces only showing namespaces that begin with lowercase letters.
## 10.3 - Cosmetics Part 2
### 10.3.6 (2019/10/30)
#### Bugfixes
Fixed a player's map timer being saved as invalid if their challenge timer was invalid.
### 10.3.5 (2019/09/01)
#### Hardcore
Updated checkpoints to Hardcore 9.0.
Old checkpoints will automatically be converted.
#### Scripts
Display names of items are now accessible.
Use Boolean Item.hasDisplayName() and String Item.getDisplayName().
#### Commands
Self-targetting /rocket is now restricted to mods and ops due to abuse.
Using /rocket as a non-operator no longer invalidates runs.
### 10.3.4 (2019/08/23)
#### Team Chat
Added /teamchat (aliases are /teammsg, /tchat, /tm and /t).
Overrides the vanilla command for better Minr-specific support.
/teamchat <message> will send a message to everyone on your team.
Players must be on a team that isn't a rank team to send or receive a message.
Subscribing
Alternatively, one can subscribe to a team channel for a team they aren't on.
Subscribers can send and receive messages in any channel they are subscribed to, regardless of the team.
The syntax is: /teamchat <team> <message>.
Subscribers are not preserved between restarts.
Subscribers can be added with /teamchat subscribe <team> <player>.
Subscribers can be removed with /teamchat unsubscribe <team> <player>.
Subscribers can be listed with /teamchat subscribe <team>.
#### Cosmetics
Hats now support player heads with custom skins.
Cosmetic GUI items now also support player heads with skins.
### 10.3.3 (2019/07/22)
#### Features
Addition of the /spectator command for Moderators.
Player names in many places (notably in the in-game player list and nameplates above other players) are now coloured by the player's rank.
The in-game player list is now sorted by rank.
#### Server Configuration
Updated to 1.14.4 (Paper #137)
#### Bugfixes
Command Block Minecarts no longer break when trying to execute Minr commands.
### 10.3.2 (2019/06/21)
#### Maps
Added announcements and special effects when obtaining 10%, 25%, 50%, 75% and 100% of all points.
#### Hardcore
Updated HC checkpoint converter to HC 8.1.
HC checkpoint converter is now more verbose and informs the player of the change.
#### Commands
Added expiration feedback to the call request.
#### Scripts
Added support for coloured player and objective names in the MSC Scoreboard API.
#### Server Configuration
All schematics have been converted to the 1.13 schematic format (.schem), which should fix irregularities in blocks and crashes (such as in Inaros).
Updated to Paper 1.13.2 #632
#### Bugfixes
Fixed issue with the command '/prefix reset' not taking arguments as intended.
Fixed command usage of the /type constructor define command: removed <returnType>.
Fixed 'This person has not requested a teleport to you within the last 5 minutes' message in /call: it now reflects the actual 1 minute expiration time.
Fixed adding of maps to a Challenge failing, but the message saying it succeeded: added more checks on the command to inform of failure.
Fixed removal of empty namespaces displaying a failing message, while the action succeeded.
Fixed attempts of removing a built-in namespace throwing a console exception.
### 10.3.1 (2019/05/24)
#### Bugfixes
Players can no longer see their own titles on occasion, which prevented interaction with the environment.
### 10.3.0 (2019/05/18)
#### Particle Trails
Adjusted the vertical offset for particle spawns (0.8 -> 1.2).
Adjusted the vertical offset for particle spawns when swimming or gliding (0 -> 0.2).
The period for particle spawns can now be customised.
Particle trails now have rarities.
Fixed particle trails now being applied on join.
#### Hats
Hats are cosmetic items, where various blocks appear on the player's head.
They can be deactivated easily by clicking on them while inside the inventory screen.
#### Prefixes
Prefixes are now time-based. They will be automatically removed are the period expires.
Removing prefixes has been simplified significantly (no longer requires magic word).
Commands are now: /prefix set <player>
#### Cosmetics GUI
Expanded the GUI to 27 slots.
Rearranged item positions slightly.
The item icons can now be customised.
Items now have a coloured name derived from their rarity.
Item lore has been significantly reformatted, and now displays requirements, rarity and multi-line descriptions.
Items can now be properly unobtainable.
Items are now sorted, first by rarity then alphabetically.
Items are now enchanted in the shop when active.
#### Rarity
Split rarities from Titles, so they can now be used by anything.
Renamed RARE to UNCOMMON.
Swapped the colours of UNCOMMON and HEROIC.
Rarity names are now displayed in game.
#### Commands
Cosmetic commands now have unified syntax, and are now ops-only.
They also all now support targetting other players, and all have "current" subcommands.
Additionally, cosmetic names within said commands are now displayed in colour.
Cosmetics can now be reloaded without a server restart, though this is not guaranteed to be safe.
Going to /spawn now resets you like entering a map does (triggering scripts when this happens in the future?).
## 10.2 - Cosmetics Update and Valentine Event
### 10.2.3 (2019/04/20)
#### Bugfixes
Fixed issue where an area script would crash the server on load when the region was deleted.
Fixed issue where User Types would break when default values were not set.
### 10.2.2 (2019/03/21)
#### Scoreboard Namespace
Added a new built-in namespace for manipulating scoreboards.
You can add or remove objectives and scores, and set the display slots of objectives.
Unlike using vanilla commands, there is no one-tick delay when using these functions.
#### Global Points
Updated global points to be somewhat more representative of top times.
Renewed formula is:
${\displaystyle base=1/{\sqrt {rank}}}$
. Everyone's score for this map is then rescaled according to the amount of completions:
${\displaystyle gpoints_{map}=(100/|F_{map}|)*base}$
${\displaystyle |F_{map}|={\sqrt {\sum base^{2}}}}$
Everyone can now use /checkpoint gpoints <player> <map>.
#### Events
Removed references to Valentines event.
#### Bugfixes
Fixed an error when deverifying a deleted Discord account.
Fixed an issue where tabbing did not work for /checkpoint gpoints.
Mapnames can now be used for /checkpoint gpoints
### 10.2.1 (2019/02/15)
#### Bugfixes
Valentine Leaderboard is now sorted by each couple's love points total.
Valentine Leaderboard now no longer opens the Challenge Leaderboard when pressing next page.
### 10.2.0 (2019/02/14)
#### Challenges
Use /marry <player> to link yourself with another player.
If one player dies, the linked player will also die.
Soul Link challenges reward Love Points as well as Challenge Points.
Use /divorce do decouple yourself from another player.
Soul Link is fully compatible with other challenge modifiers.
#### Cosmetics
Particle Trails.
Added particle trails. When you move, a trail of particles will be left behind you.
Added "Love Trail" particle trail, which requires 300 Love Points.
Added "Completionist" particle trail, which requires 100% of all points obtained.
Cosmetics GUI
Added new GUI for managing cosmetics, openable with /cosmetics (alias: /shop).
#### Events
A special Valentines event is running from Febuary 14th to March 14th, centred around Soul Link challenges. The top five couples with the most Love Points at the end of the event will unlock an exclusive title. Gain 300 Love Points to unlock the "Love Trail" particle trail.
#### Commands
/cosmetics
Alias: /shop
Opens the Cosmetic GUI.
/trail
Alias: /trails
Operators Only:
/trail give <player> <trail> gives a player a particle trail.
/trail take <player> <trail> takes a particle trail from a player.
The following commands were also added for everyone, but may be removed at a later date.
/trail set <trail> enables a particle trail.
/trail list shows all your particle trails.
/trail clear disables your currently active particle trail.
/titles
/titles list was changed to be similar to /trail list.
/valentine
/valentine ranks shows the current event leaderboard.
/valentine completed <player> shows the current event leaderboard.
/marry <player> to link with another player.
/hide
/hide <player> hides a player from you.
If a player relogs they will become visible again.
#### Bugfixes
Titles no longer persist after logout in a vehicle.
Titles have more debug measures such that it is easier to track the cause of persisting titles.
Fix valid Scripts throwing OutdatedException when slay (and others) is used as a parameter in @bypass.
## 10.1 - Difficulty Rework
### 10.1.5 (2019/01/08)
#### Bugfix
Fixed repeating challenges subtracting challenge points.
### 10.1.4 (2019/01/08)
#### Bugfix
Fixed repeating challenges having an extreme reward.
### 10.1.3 (2019/01/07)
#### Bugfixes
Fixed recent invalid times overwriting valid times.
Fixed leaderboards not updating on removal of completions.
### 10.1.2 (2019/01/04)
#### Bugfixes
Fixed force joining challenges skipping requirements check.
Invalid but legitimate times on maps are now saved.
Fixed /whois showing the executor's points instead of the target's.
### 10.1.1 (2019/01/02)
#### Commands
A breakdown of where challenge points have been otained is now shown in /c points.
#### Bugfix
Fixed an error when regenerating a challenge before the leaderboard is setup.
### 10.1.0 (2018/12/31)
#### Difficulty Brackets
Added new difficulty brackets, white and black. Rebalanced the number of points awarded by each bracket. Renamed some of the brackets.
The difficulty spectrum is now as follows:
• White, "Very Easy" - awards 1 point
• Blue, "Easy" - awards 2 point
• Green, "Novice" - awards 4 point
• Yellow, "Moderate" - awards 7 point
• Orange, "Hard" - awards 12 point
• Red, "Very Hard" - awards 18 point
• Black, "Very Expert" - awards 25 point
Completions of black maps are now announced in chat like red maps. FFA Points have now been renamed to Points.
#### Hardcore
Whities are now automatically promoted to Blue once they meet the Hardcore point threshold, before entering Hardcore.
Entry to Hardcore now requires 35 points plus completion of the FAQ Quiz.
Completions of individual Hardcore maps are now announced.
#### Scripts
Local variables have been reworked internally. Chat scripts should behave properly now as a result.
Improved error messages when an exception occurs while importing a script.
If an exception occurs when adding or importing a script, the script will not be modified.
#### Bugfixes
Fixed issues when redefining or removing regions with scripts bound to them.
Methods now work on fields.
/type constructors and /type methods can now be used on built-in types.
## Prior to 10.0.0
Please consult the announcements forum. https://forums.minr.org/forums/news-announcements.18/ | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 3, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.2863466441631317, "perplexity": 14303.53562767633}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 20, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2021-04/segments/1610703587074.70/warc/CC-MAIN-20210125154534-20210125184534-00766.warc.gz"} |
https://quant.stackexchange.com/questions/32138/calculating-the-pair-weights-from-log-price-hedge-ratio | # calculating the pair weights from log price hedge ratio
I am calculating the hedge ratio using log prices:
$$\ln(A) = \text{hedge_ratio} \cdot \ln(B)$$
How do I convert the hedge_ratio into a number of shares of A vs. a number of shares of B?
Think in terms of dollars invested, not shares. A hedge ratio of 2 for example means that Stock A will go up 2% (on a logarithmic basis, i.e. $\ln P_{t+1}=\ln P_t+0.02$) when Stock B goes up 1%. That means you need twice as many dollars invested in B as in A for the movements to offset each other in dollar terms.
Once you decide what these amounts should be (based on a position size rule, say 10000 USD for the most volatile of the two stocks, or other more complicated rule) you just divide 10000 and 20000 by the respective prices to determine the number of shares (e.g. $10000/P_A$ and $20000/P_B$). | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 1, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.37918728590011597, "perplexity": 1020.0300133916431}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2020-05/segments/1579251705142.94/warc/CC-MAIN-20200127174507-20200127204507-00044.warc.gz"} |
https://hal-insu.archives-ouvertes.fr/insu-02047069 | Chemical Aging of Titan's Tholins Exposed to Solar Radiation in Low Earth Orbit onboard the EXPOSE Facility - Archive ouverte HAL Access content directly
Conference Papers Year :
Chemical Aging of Titan's Tholins Exposed to Solar Radiation in Low Earth Orbit onboard the EXPOSE Facility
(1) , (1) , (2) , (2) , (2) , (3) , (2) , (2)
1
2
3
Cyril Szopa
Nathalie Carrasco
Patrice Coll
• Function : Author
• PersonId : 1043165
Hervé Cottin
• Function : Author
• PersonId : 963259
Didier Chaput
• Function : Author
• PersonId : 1043166
Katia Grira
• Function : Author
• PersonId : 1043167
Diana Khalaf
• Function : Author
• PersonId : 1043168
Abstract
Titan's organic aerosols are produced from the chemistry occurring in the atmosphere from gaseous N2 and CH4 submitted to UV solar radiation and energetic particles from Saturn magnetosphere. Our direct knowledge about their chemical composition is limited but we know they are among the most complex organic materials on Titan, composed of a solid core incorporating at least both carbon, hydrogen and nitrogen atoms. This chemistry is unique in the solar system and it could help understanding pathways of the prebiotic chemistry that resulted in the emergence of life. Titan's aerosols composition is indirectly studied through the production and analysis of analogues, called tholins, using laboratory experiments which mimic Titan's atmosphere chemistry conditions. But usually, these tholins are analyzed straight after their production, and it is only recently that the question of their aging was raised. In particular, the aging of the Titan's aerosols submitted to solar radiation during their long descent to the satellite surface was studied in the laboratory using specific UV wavelengths (1). With the same objective, Titan's tholins were exposed to the direct solar radiation in low Earth orbit using the ESA's EXPOSE facility mounted outside the ISS for months. Two varieties of tholins with different chemical properties were produced with the PAMPRE laboratory experiment (2), the first one using a (98:2) N2:CH4 gaseous mixture, and the other one, a (90:10) one. Increasing the amount of initial methane results in a more aliphatic material. These samples were exposed to the same solar radiation for the months the EXPOSE facility was mounted outside ISS. The chemical properties of these samples measured before the flight and after their return to the laboratory were compared. They clearly showed that both tholins structure have been modified in some extent by the solar radiation. Thanks to control samples placed in the EXPOSE facility in blind cells, and in a facility in the laboratory, this evolution can be definitely attributed to UV radiation. We present here the corresponding results and the consequences we can deduce for the aging of the Titan's aerosols Ref:[1]Carrasco N.(2018) Nat. Ast. [2] Szopa C. (2005) Planet. Space Sci.
Dates and versions
insu-02047069 , version 1 (23-02-2019)
Identifiers
• HAL Id : insu-02047069 , version 1
• BIBCODE :
Cite
Cyril Szopa, Nathalie Carrasco, Patrice Coll, François Raulin, Hervé Cottin, et al.. Chemical Aging of Titan's Tholins Exposed to Solar Radiation in Low Earth Orbit onboard the EXPOSE Facility. American Geophysical Union, Fall Meeting 2018, Dec 2018, Washington, United States. ⟨insu-02047069⟩
107 View | {"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8459071516990662, "perplexity": 5640.646164018082}, "config": {"markdown_headings": false, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.3, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2023-06/segments/1674764499758.83/warc/CC-MAIN-20230129180008-20230129210008-00767.warc.gz"} |
https://socratic.org/questions/what-is-the-slope-of-the-tangent-line-of-x-y-2-3xe-y-2-c-where-c-is-an-arbitrary | Calculus
Topics
# What is the slope of the tangent line of (x-y^2)/(3xe^(y^2)) =C , where C is an arbitrary constant, at (1,5)?
Oct 22, 2016
The slope, $m = \frac{5}{46}$
#### Explanation:
Specifying the point $\left(1 , 5\right)$ makes C become a defined constant:
$C = \frac{1 - {5}^{2}}{3 \left(1\right) \left({e}^{{5}^{2}}\right)} = \frac{- 24}{3 {e}^{25}} = - 8 {e}^{- 25}$
However, this has no bearing on the slope of the tangent line, because it will be 0, when we differentiate:
$\frac{d \left(- 8 {e}^{- 25}\right)}{\mathrm{dx}} = 0$
Use the Quotient Rule to differentiate the left side:
$f \left(x , y\right) = g \frac{x , y}{h \left(x , y\right)}$, then $f ' \left(x , y\right) = \frac{g ' \left(x , y\right) h \left(x , y\right) - g \left(x , y\right) h ' \left(x , y\right)}{h \left(x , y\right)} ^ 2$
Let $g \left(x , y\right) = x - {y}^{2}$, then $g ' \left(x , y\right) = 1 - 2 y \frac{\mathrm{dy}}{\mathrm{dx}}$
Let $h \left(x , y\right) = 3 x {e}^{{y}^{2}}$, then $h ' \left(x , y\right) = 3 {e}^{{y}^{2}} + 6 x y {e}^{{y}^{2}} \frac{\mathrm{dy}}{\mathrm{dx}}$
This is equal to 0, therefore, we can rid ourselves of the denominator by multiplying both sides by it.
Substitute the above into the numerator and set it equal to 0:
$\left(1 - 2 y \frac{\mathrm{dy}}{\mathrm{dx}}\right) \left(3 x {e}^{{y}^{2}}\right) - \left(x - {y}^{2}\right) \left(3 {e}^{{y}^{2}} + 6 x y {e}^{{y}^{2}} \frac{\mathrm{dy}}{\mathrm{dx}}\right) = 0$
$\left(1 - 2 y \frac{\mathrm{dy}}{\mathrm{dx}}\right) \left(3 x {e}^{{y}^{2}}\right) + \left({y}^{2} - x\right) \left(3 {e}^{{y}^{2}} + 6 x y {e}^{{y}^{2}} \frac{\mathrm{dy}}{\mathrm{dx}}\right) = 0$
3xe^(y^2) - 6xye^(y^2)dy/dx + 3(y^2 - x)e^(y^2) + 6xy(y^2 - x)e^(y^2)dy/dx) = 0
$3 {y}^{2} {e}^{{y}^{2}} - 6 x y {e}^{{y}^{2}} \frac{\mathrm{dy}}{\mathrm{dx}} + 6 x y \left({y}^{2} - x\right) {e}^{{y}^{2}} \frac{\mathrm{dy}}{\mathrm{dx}} = 0$
$3 {y}^{2} {e}^{{y}^{2}} + 6 x y \left({y}^{2} - x - 1\right) {e}^{{y}^{2}} \frac{\mathrm{dy}}{\mathrm{dx}} = 0$
$6 x y \left({y}^{2} - x - 1\right) {e}^{{y}^{2}} \frac{\mathrm{dy}}{\mathrm{dx}} = 3 {y}^{2} {e}^{{y}^{2}}$
$\frac{\mathrm{dy}}{\mathrm{dx}} = \frac{3 {y}^{2} {e}^{{y}^{2}}}{6 x y \left({y}^{2} - x - 1\right) {e}^{{y}^{2}}}$
$\frac{\mathrm{dy}}{\mathrm{dx}} = \frac{y}{2 x \left({y}^{2} - x - 1\right)}$
The slope, m, is the above evaluated at the point $\left(1 , 5\right)$:
$m = \frac{5}{2 \left(1\right) \left({5}^{2} - 1 - 1\right)}$
$m = \frac{5}{2 \left(23\right)}$
$m = \frac{5}{46}$
##### Impact of this question
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https://www.askmehelpdesk.com/coins-paper-money/20-bill-misprint-451711.html | My $20 bill has a small little green star on the top left hand corner next to the serial number I already checked a lot of$20 and none have the little green star could this be a small misprinted bill?? | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.36957624554634094, "perplexity": 4254.80622081604}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2018-22/segments/1526794867173.31/warc/CC-MAIN-20180525180646-20180525200646-00133.warc.gz"} |