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|Feb3-08, 12:04 PM||#1| What is Heat? Written by Hootenanny. Edited by berkeman and Kurdt. Feel free to contact me with any questions, comments or corrections. What is Heat? One of the most frustrating misconceptions in Thermodynamics centres on the actual definition of heat. Many science/engineering students often ref...
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Research Highlights : Physics Smaller, cheaper and better 31 October 2008 (Volume 3 Issue 10) A new design for compact free-electron lasers leads the way towards exploiting extremely short wavelengths Figure 1: A view at the beam hall of the FEL test facility. The electron gun is contained in the grey box on the left.e...
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Carbon is the sixth element on the periodic table, having six protons in its nucleus. The most common number of neutrons in its nucleus is also six and the Carbon-12 isotope is the basis for atomic weights, with the mass of the proton being defined as 1/12 of the mass of the Carbon nucleus. The next most common isotopo...
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Cirripedes (barnacles) are known for their sessility – it’s their defining characteristic. They count as one of the first model organisms of evolutionary biology, having been comparatively studied by Darwin for over 8 years (one would think they’re his favourite animals – although this letter says otherwise!). The 4 re...
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Melting polar ice has a worrisome list of consequences—methane gas release, rising sea levels, and the liberation of long frozen 750,000-year-old microbes. While melting glaciers probably aren’t going to turn into Jurassic Park, scientists are understandably concerned how they might affect the environment. Scientific A...
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The .Net framework defines operator overloads for the + and - operators on the Delegate data type. The + operator effectively combines delegates so that a multiple delegates are called within one. The - operator, on the other hand, attempts to remove the delegate invocation list from a delegate. The list discinction is...
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suppress is equivalent to In the format string zis a format modifier that turns off all translate rules, his a format modifier that turns off all line-breaking rules, and %is the parse continuation operator. The following sample code demonstrates the use of suppress in a simple SGML program. The program prints all of t...
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Equilateral Triangle Areas Library Home || Primary || Math Fundamentals || Pre-Algebra || Algebra || Geometry || Discrete Math || Trig/Calc |Annie Fetter & Steve Weimar (extra)| |Geometry, difficulty level 3. If two equilateral triangles have edgelengths of 9 cubits and 12 cubits, what's the edgelength of the equilater...
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I found these clocks in the Arts Centre at the University of Warwick intriguing - do they really need four clocks and what times would be ambiguous with only two or three of them? A bicycle passes along a path and leaves some tracks. Is it possible to say which track was made by the front wheel and which by the back wh...
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In mathematics, a rational number is a number which can be expressed as a ratio of two integers. Non-integer rational numbers (commonly called fractions) are usually written as the vulgar fraction a / b, where b is not zero. a is called the numerator, and b the denominator. Each rational number can be written in infini...
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Climate change explained The Earth’s climate is driven by a continuous flow of energy from the sun. Heat energy from the sun passes through the Earth’s atmosphere and warms the Earth’s surface. As the temperature increases, the Earth sends heat energy (infrared radiation) back into the atmosphere. Some of this heat is ...
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|South of Antares, in the tail of the nebula-rich constellation Scorpius, lies emission nebula Nearby hot, massive stars, millions of years young, nebula with invisible ultraviolet light, stripping electrons The electrons eventually recombine with the atoms to produce the visible dominated by the red emission of hydrog...
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the Full Moon will planet Earth's shadow in a The entire eclipse sequence, including 51 minutes of totality, will be visible from Asia and Australia, but moonwatchers in Europe and Africa will miss out on the beginning partial phases because for them, the eclipse will start before In central and western North America t...
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- Recorder Online - http://www.berthoudrecorder.com - Earthsky Tonight—May 7, See the legendary green flash Posted By Gary Wamsley On May 6, 2010 @ 10:53 pm In Earth & Sky | Comments Disabled Courtesy of EarthSky A Clear Voice for Science Our image today was taken by Mike Baird . It is a classic image of a detached gr...
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The log of a molecule's molecular weight is proportional to the distance that molecule has migrated. Therefore, the first step is to generate a standard curve using molecules of know size (the molecular When using semilog paper (see the next page), the molecular weights (in bp for DNA and kiloDaltons, kDa, for proteins...
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2 min 20 sec Today, about one in four molecules of carbon dioxide in the atmosphere come from human activity, mainly burning fossil fuels. We also know that carbon dioxide, or CO2, is a "greenhouse gas" — it traps extra energy from the sun and warms the earth. Carbon dioxide levels in the air have been increasing every...
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The Document Object Model: an Introduction Published on May 14, 2001 Definition of a Document Object Model A Document Object Model is a model of how the various HTML elements in a page (paragraphs, images, form fields, etc.) are related to each other and to the topmost structure: the document itself. So the document is...
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- Sir Bernard Lovell - Planck First Results - Lovell Telescope - SKA Telescope - New Discovery Centre - ALMA Fringes - Active Galaxies - The Sun - PhD Studentships - Night Sky - Behind the Scenes - Sounds of Space - Meteor Detector It is with regret that we announce that Sir Bernard Lovell OBE FRS died on the 6th Augus...
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returns a pointer to a string containing the name of the user logged in on the controlling terminal of the process, or a null pointer if this information cannot be determined. The string is statically allocated and might be overwritten on subsequent calls to this function or to returns this same username in the array r...
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But is the increase in shark sightings due to the Gulf of Mexico oil spill? Perhaps not, explains George Burgess, director of Florida program for shark research at the University of Florida "It may be a situation where there's more people out there looking for things than there were before," he said. Warmer temperature...
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Australian cows are doing what they do best - ruminating and burping - for scientists who last month began an experiment to measure the contribution cattle make to the greenhouse effect. Cud-chewing animals such as cows, sheep and goats produce methane as they digest their food. This is thought to represent an estimate...
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HYDROGEN is the darling of alternative fuel proponents. But Olah, a Nobel laureate, Prakash and Goeppert argue that methanol is better, despite its higher toxicity. It is a liquid, so it is easier to ship and store. Today it can be created from natural gas. The authors' real dream is of a future in which nuclear or ren...
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In 1931 Kurt Gödel wrote an important paper in which he showed that an axiomatic system which contained the axiom of infinity could not be proved to be consistent or complete. The trouble does not exist, however, for finite systems. As a result, one might be tempted to confine their research interests to solely finite ...
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Giant Tree Lobsters Rediscovered Eighty years after they disappeared, tree lobsters have been rediscovered, living near an old volcano in Australia. And no, they’re not actually “lobsters,” but special six-legged insects that were thought to be extinct decades ago. The rare “tree lobsters,” otherwise commonly known as ...
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How is freezing rain different than sleet? Published: Jul 27 2011 10:34:13 AM EDT Freezing rain is rain which freezes on impact with a cold surface (below 32 degrees creating a glaze). Sleet occurs when raindrops freeze as small ice pellets BEFORE they hit the surface of the earth. » More Homework Help Questions
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Note: This project has been replaced by the BEC project. An Optical lattice (OL) is an array of periodic light-shift potentials formed due to interference of two or more laser beams. Atoms are cooled and localized in the potential minima. OL demonstrate many of the characteristics associated with solid state lattices, ...
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Database Server System Requirements From the point of view of the operating system, a database server requires the system resources described in the following sections. The amount of physical memory used by the database server process is determined by parameters in the local database definition, see The Local Database,...
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Garbage collection (GC) reclaims the heap space previously allocated to objects no longer needed. The process of locating and removing the dead objects can stall any application and consume as much as 25 percent throughput. Almost all Java Runtime Environments come with a generational object memory system and sophistic...
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Black Hole Eats Star, Beams Signal to Earth On March 28, 2011, NASA's Swift detected intense X-ray flares thought to be caused by a black hole devouring a star. In one model, illustrated here, a sun-like star on an eccentric orbit plunges too close to its galaxy's central black hole. About half of the star's mass feeds...
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This data set consists of exposure ages for glacial deposits on nunataks and ice-free areas adjacent to Scott Glacier, Transantarctic Mountains. Most samples are glacially transported clasts deposited during the last glacial period or exposed by subsequent retreat of the glacier, ca. 16,000 yr B.P. to present. These ag...
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There are several types of indexes are available in MySQL: - B-Tree Indexes: - Normal Indexes – Normal indexes are the most basic indexes, and have no restraints such as uniqueness. It can contain duplicate value. - Unique Indexes – Unique indexes are the same as “Normal” indexes with one difference: all values of the ...
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Spotted Garden Eel Heteroconger hassi These eels spend their lives swaying gracefully to and fro with their heads up in the water and their tails in their sandy burrows. Several hundred fish live together in a colony, or “garden,” looking like evenly spaced plants blowing in the breeze. Garden eels are much slimmer tha...
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Part of twisted.flow.stage View Source View In Hierarchy Merges two or more Stages results into a single streamFor example: source = flow.Zip([1,flow.Cooperate(),2,3],["one","two"]) printFlow(source) |Method||_yield||executed during a yield statement by previous stage| Inherited from Stage: |Method||next||return curren...
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According to the rock record, until about a million years ago the climate followed a neat 41,000-year cycle of ups and downs. Then, abruptly, that cycle stopped operating, and another one — 100,000 years long — took over. Why? Some scientists speculated that a cosmic catastrophe had reset the climatic clock. Others sim...
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The fossil was originally described (Radoičić, 1959) as minute thick-walled cylindrical bags closed at one end, ca 500 to 780 µm long, with 32 to 80 µm external and 10 to 24 µm internal diameters. It was ascribed to the genus Aeolisaccus Elliott, 1958, under the name A. kotori Radoičić, 1959. A supplementary descriptio...
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We can use what we know of arithmetic sequences to understand arithmetic series. An arithmetic series is a series or summation that sums the terms of an arithmetic sequence. There are methods and formulas we can use to find the value of an arithmetic series. Understanding arithmetic series can help to understand geomet...
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The visible satellite imagery is essentially a snapshot of what the satellite sees, unlike Infrared (IR) satellite imagery, which depicts the temperature of the clouds. As the sun approaches midday over a given area, clouds will appear as bright white, as opposed to gray at sunrise and sunset. This is due to more sunli...
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Sometimes mathematicians play "fast and loose" with definitions. We probably will not find total agreement about what a "polynomial" is. Some books will define "a polynomial in x" as opposed to just a polynomial. And what about a "polynomial in two variables?" If y=2+x is x+y a binomial? And what does "quotient" refer ...
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How to Spot The Comet This Week Two comets visible in the Chilean night sky, March 2013. PANSTARRS is seen in the lower right. Credit: Juri Beletsky, Observatorio de Las Campanas, Chile. The first of two great comets expected to be visible to the naked eye in 2013 makes its flyby this weekend. Comet PANSTARRS will be c...
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Java multi-threading Javamulti-threading What method is invoked to cause an object to begin executing as a separate thread Java multi-threading Javamulti-threading How does multithreading take place on a computer with a single CPU Multi-Threading - Java Beginners Multi-Threading Consider a producer process prime-genera...
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Posted Sunday, March 10, 2013, at 8:00 AM I worked with Hubble Space Telescope (HST) for many years. First it was with early data (taken weeks after launch) for my PhD research, and then several years helping to build and calibrate a camera on board called STIS. Working with HST (as those of us in the know call it) and...
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Bring Back Project Pilot Most people have never heard of Project Pilot, the U.S. Navy’s maverick air-launched orbital booster program of 1958. Those who have call it an interesting failure. The project probably put one satellite in orbit in six launch attempts. It had minimal effect on the future: The designer of today...
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HYPERSPHERE VISUALISATION AND LENSING. This paper provides a method of visualising the four dimensional hypersphere as a perspective construction in three dimensions, and it also shows how the curvature of hyperspherical space will distort images from distant galaxies and supernovae. Figure 1. Any attempt to project th...
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In this interactive activity adapted from NOVA Online, learn how a typical photovoltaic cell converts solar energy into electricity. Explore the components of a photovoltaic cell, including the silicon layers, metal backing, antireflective coating, and metal conductor strips. Using animations, investigate why the silic...
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Want to stay on top of all the space news? Follow @universetoday on Twitter A mass driver is a proposed device for propelling objects by using electromagnets. It was first conceptualized in the 1970′s as a possible method to launch rockets into space but still has to come into fruition. Think of it as a linear accelera...
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Manipulate directed acyclic graphs Date/Time of Processing: Tuesday 24 May 1994 12:53:46Pm Overall Assessment of System: OK Classification of System: B Basis of Classification -- Syntax Errors PASS Completeness PASS Independence from External Libraries FAIL Independence from a Specific Ada Compiler PASS Explanations fo...
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Published March 17, 2010 Amphipods , Hemipterans (True Bugs) , Isopods (Pill Bugs) , Uncategorized Tags: Antarctica, Aphids, Biofuel, Genomics, Limnoria, Limnoriids, Lyssianasids Quick blurbs about arthropod research and news: - NASA climate researchers have discovered animal life deep below the Pine Island Glacier Ice...
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The total eclipse of 1999 August 11 is the twenty-first member of Saros series 145 (Table 37), as defined by van den Bergh . All eclipses in the series occur at the Moon's ascending node and gamma1 decreases with each member in the family. The series is a young one which began with a minuscule partial eclipse at high n...
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Previous Next Edit Rename Undo Refresh Search Administration Static Sub IndexMask ( Mask As Integer ) the writing of individual bits in the color index buffers. Specifies a bit mask to enable and disable the writing of individual bits in the color index buffers. Initially, the mask is all 1's. controls the writing of i...
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What is Phase? As a sinoidal signal in the time domain can be defined as The signal phase describes an 'offset' of the signal along the time axis and defines the 'zero crossing' of the signal. An sinoid signal is periodic, therefore usually only phase values from +/-180deg (or +/-Pi) are used. You see here an sinoidal ...
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Value Types and Reference Types A data type is a value type if it holds the data within its own memory allocation. A reference type contains a pointer to another memory location that holds the data. Reference types include the following: All arrays, even if their elements are value types Class types, such as Form You c...
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Computer Simulations of the Martian Atmosphere Interacting with the Solar Wind Tom Bridgman, Marte Newcombe, Cindy Starr, Naoki Terada, Hiroyuki Shinagawa, NASA GSFC Scientific Visualization Studio, NASA GSFC Scientific Visualization Studio, NASA GSFC Scientific Visualization Studio, Solar-Terrestrial Environment Labor...
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Investigate how this pattern of squares continues. You could measure lengths, areas and angles. A man paved a square courtyard and then decided that it was too small. He took up the tiles, bought 100 more and used them to pave another square courtyard. How many tiles did he use altogether? Can you work out the area of ...
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The extent of adsorption of a gas on the surface of a solid depends on the following factors: (a) Nature of gas (b) Nature of solid (c) Specific area of solid (d) Pressure of gas (f) Activation of solid (i) Nature of gas: Since physical adsorption is non-specific in nature, any gas will be adsorbed on the surface of a ...
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An infinitely long, thin conducting sheet defined over the space \(0<=x <= \infty\) and \(-\infty <= y <=\infty\) is carrying a current with a uniform surface current density \(J_s=a_y5\) . (a) write down R (b) what is the direction of dI x R? Note that I is the current vector (c) Calculate B (note you may need to pref...
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public member function explicit binomial_distribution ( result_type t = 1, double p = 0.5 ); explicit binomial_distribution ( const param_type& parm ); Construct binomial distribution Constructs a binomial_distribution object, adopting the distribution parameters specified either by t and p or by object parm. - The upp...
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The phosphatases are enzymes which catalyse the transfer of the phosphate radical (PO4) between the inorganic ionic state, as in sodium phosphate, and attachment to an organic radical, as in glucose 6-phosphate. There are numerous kinds of phosphatase in the body. One of these, red-cell acid phosphatase, is present in ...
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On December 25, 1999, another "Chesapeake Bay" effect snow event occured within the Wakefield CWA. As in the November 30, 1999 case, very cold 850 MB temperatures were indicated across the area. 850 MB temperatures were in the -10C to -15C range across the area where the "bay effect" plume was generated. Bay water temp...
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Given three disjoint circles A, B and C of unequal radii situated entirely in each other's exterior, the common internal tangents of circles A and C meet in Y, the common internal tangents of circles A and B meet in Z and the common external tangents of circles B and C meet in X. Then the points X, Y and Z are collinea...
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Maintained by W-W There are two main reasons for studying the Sun. First, there is the practical need to understand how changes at the Sun's surface affect the flow of energy and of dangerous radiation to Earth. Second, the Sun is the only star that is close enough to study its surface in detail. What we learn about su...
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Why is 30 the “Magic Number” for Sample Size? It seems like whenever people learn about statistical problem solving, the sample size question comes up. Invariably, the number 30 is bandied about as a sweet spot that should get the job done. Astute learners generally want to understand why 30 seems to work. Read on to f...
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THE future of biofuels just got brighter. Yields from farm-scale plantings of the switchgrass Panicum virgatum suggest that producing ethanol from the cellulose in these crops will be about twice as energy-efficient as previously estimated. Researchers led by Ken Vogel of the US Agricultural Research Service in Lincoln...
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Uses of linear programming Name: nick j wilwert Date: Around 1995 Could you list some ways in which linear programming is used in real life? There is a journal called "The Journal of Operations Research" that contains articles by people who apply linear programming to everyday problems. One of the classic applications ...
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Search our database of handpicked sites Looking for a great physics site? We've tracked down the very best and checked them for accuracy. Just fill out the fields below and we'll do the rest. You searched for We found 16 results on physics.org and 215 results in our database of sites 207 are Websites, 4 are Videos, and...
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Please sign up, comment on articles and bring your friends! The best way to predict the future is to create it. The researchers used high-speed light sheet microscopy to image the activity of 80% of the neurons in the brain (which is composed of ~100,000 neurons) of a fish larva at 0.8 Hz (an image every 1.3 seconds), ...
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This PEP has been withdrawn in favor of PEP 3141. Today, Python's numerical model is similar to the C numeric model: there are several unrelated numerical types, and when operations between numerical types are requested, coercions happen. While the C rationale for the numerical model is that it is very similar to what ...
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The process of detecting and monitoring the physical characteristics of an area by measuring its reflected and emitted radiation at a distance from the targeted area. Remote sensing is used in this thesaurus to refer to methods that are solely or primarily deployed through air or space. Included in this concept are stu...
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www.windaction.orgfacts, analysis, exposure of wind energy's real impactsWindactionhttp://www.windaction.org/articles/c38+111?theme=atomXarayar2006-06-12T02:16:27ZWind turbine pressure change kills bats, research may help prevent future deaths.364212012-10-30T10:27:36Z2012-10-30T10:27:36ZMiles away, wind turbines sat m...
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Mars Student Imaging Project The Mars Student Imaging Project (MSIP, sometimes called Mars Student Imaging Program) is a collaboration between NASA and Arizona State University's Mars Education Program that gives United States grade school students the opportunity to participate in Mars research. Students from grade 5 ...
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Comprehensive DescriptionRead full entry BiologyNear shore and in bays. Very common, has been successfully introduced to Lakes Kava, Kariba and Carbora Bass (Ref. 4967). A lacustrine species, preferring open water (Ref. 13337). Forms large schools. Mainly nocturnal and feeds on plankton (especially atyid shrimps, also ...
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Energy and Magnitude of the Sliding Block The following unit definitions are from: http://www.unc.edu/~rowlett/units/index.html newton (N) the SI unit of force. A force of one newton will accelerate a mass of one kilogram at the rate of one meter per second per second. The corresponding unit in the CGS system is the dy...
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This post is about the LHCb – the motivations and science behind the experiment, and what scientists hope to discover there. The LHCb is one of four experiments at the Large Hadron Collider (LHC) at CERN in Geneva. It will study the decays of particles known as B mesons in the hope of discovering the answer to a proble...
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The father of genetics, Gregory Mendel, discovered that pea plants passed certain traits on to their offspring. Once we began to explore genetics, we found a complex system of proteins that make up every living thing on Earth. This complex system, DNA, is so difficult to decode that even though the entire human genome ...
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A game that tests your understanding of remainders. In a square in which the houses are evenly spaced, numbers 3 and 10 are opposite each other. What is the smallest and what is the largest possible number of houses in the square? In this article for teachers, Bernard Bagnall describes how to find digital roots and sug...
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I’ve heard from the likes of Brian Cox that what we see of the sun during a sunset and sun rise is actually the mirage of the sun. The Sun has actually set/risen and we see it due to the way light is bent across the atmosphere. Apparently due to coincidence of the size and distance of the sun, its exactly the same size...
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Analysis confronts model of universe’s formation Nov 16, 2007 2 comments Tiny temperature variations found in maps of the cosmic microwave background are commonly thought to be proof that stars, galaxies and other large-scale structures grew from density perturbations in the early universe. But one physicist in the US ...
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Some people love washing their cars, but many folks would appreciate having the fresh-from-the-showroom look without all of the effort. And don't forget the environmental impact of car washing, which drains water reserves and spills pollutants into endangered wetlands. If only our cars would clean themselves. Thanks to...
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Calculate ionospheric equivalent currents (1D) From ground magnetometer data the ionospheric equivalent currents can be calculated. These are currents that flow only within the ionospheric plane (assumed at 100 km altitude) and cause the same magnetic field on the ground as the actual ionospheric current system (which ...
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What's the point of a triploid tissue? koning at ECSUC.CTSTATEU.EDU Thu Feb 27 09:32:05 EST 1997 At 7:16 AM -0000 2/27/97, John Hewitson wrote: >My students ask "What's the point of a triploid tissue?" >The thinking goes like this:- >* Triploid tissue is unique to angiosperms. True? >* Natural selection does not suppor...
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Glen Paul: G'day and welcome to CSIROpod, I'm Glen Paul. You're probably familiar with the East Australian current, if from nothing more than the 2003 animated film Finding Nemo, where the current is portrayed as a super-highway for marine life to travel down the East Coast of Australia. In a recent paper published in ...
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You already know how to link XML documents together with XLink, and isolate specific nodes or node collections with XPath. Now uncover the third and final piece of the XML linking jigsaw - XPointer, an experimental technology from the W3C, which allows you to create XML links to specific points or ranges within an XML ...
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In NIU's Math Education Lab, brightly colored Macintosh computers sit all in a row. Hundreds of Tupperware containers line the shelves on the wall, each containing a different material used in demonstrating math concepts, such as pattern blocks, geoboards and base blocks. The shelves on both sides of the room are fille...
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On January 30, 2012, the Schmidt Ocean Institute ship Lone Ranger returns to the Sargasso Sea for a third time with Ken Smith and Alana Sherman aboard to continue their study on the effects of climate variation on the sea-surface communities and deep-sea ecosystems. This third Sargasso Sea research expedition is a coll...
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the quantity of electric charge that, passed though an ionic solution, will cause electrolysis of one equivalent of ions; it is equal to about 96,490 coulombs. The number of univalent metal ions (such as silver in a silver nitrate solution) which would be deposited as free metal by such a current is Avogadro's number, ...
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Photograph courtesy Beth Shapiro Beth Shapiro travels through time—observing mammoths, dodos, and other extinct animals; witnessing the last ice age and arrival of humans in North America; watching genetic diversity shrink in one species while blossoming in another. Her journey is made possible by ancient DNA samples a...
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When the Leonid meteor storm hits the Earth on 17 November, the Hubble Space Telescope will be turned away from the onslaught to protect its delicate optics. But the time will be put to good use. Teams from the University of New South Wales in Sydney, NASA's Goddard Space Flight Center in Greenbelt, Maryland, and the U...
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In the Solar System, the region beyond Neptune. It includes more than 70,000 small objects, a number up to asteroidal size. It is located from 30 to 50 A.U.'s and was discovered in 1992. The Kuiper belt may be the source of the short-period comets (like Halley's comet). The Kuiper belt was named for the Dutch-American ...
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(often represented by the generic formula HA ]) is traditionally considered any chemical compound that, when dissolved in water , gives a solution with a hydrogen ion activity greater than in pure water, i.e. a pH less than 7.0. That approximates the modern definition of Johannes Nicolaus Brønsted and Martin Lowry , wh...
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C2 Epstein Diagrams The dogma reads: Everybody is always and everywhere moving at the speed of light c in 4D space-time. Everyone calls the direction in which they move their time and the directions orthogonal to it form their space. One second of time therefore corresponds to 299,792,458 m (≈ 300,000 km) of space (tha...
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The word synoptic means "view together" or "view at a common point". Therefore, synoptic meteorology is primarily concerned with viewing the weather at a common point -- time. Also known as large scale or cyclonic scale, the size of weather patterns we are looking at range upwards from about 620 miles (1,000 kilometers...
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Common Names in English: 'The Nymphalidae are members of the Superfamily Papilionoidea, the true butterflies. Distributed worldwide, butterflies of this family are especially rich in the tropics. They are highly variable, and there are more species in this family than in any other. Adults vary in size from small to lar...
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Not many of you will believe that hagfish, also called snot-eels, are fascinating creatures, but they truly are. You will only be able to believe me after reading this post. I still persist saying that I am not falling in love with them but some of my colleagues start worrying about my desire to always know more on the...
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Carlo Zapponi created Bolides, a fantastic animated visualization of meteorites that have been seen hitting the Earth. The data source is the Nomenclature Committee of the Meteoritical Society's Meteorite Bulletin. "The word bolide comes from Greek βολίς bolis, which means missile. Astronomers tend to use bolide to ide...
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I don't really get how the authors came up with their three models: - the "Paleolithic" model assumes beginning of expansion at 21 kBP; as this was unsupported under any mutation rate, I won't bother with it further. - the "Neolithic" models had expansion beginning at 10.5kBP, that is about 2k prior to the known earlie...
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Tuesday, April 17, 2012 - 14:00 in Biology & Nature Lobes of fat connecting to their ears may allow baleen whales to hear underwater. - Researchers find first genetic evidence for loss of teeth in the common ancestor of baleen whalesWed, 29 Sep 2010, 17:23:24 EDT - Scientists use marine robots to detect endangered whal...
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Spring Pygmy Sunfish, One of Alabama's Rare Fishes Keith B. Floyd Alabama is blessed with an abundance of streams and rivers. This large amount of fresh water provides a home to over 306 native freshwater species. Alabama is second only to Tennessee in the number of freshwater fish species found in a state. These diver...
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(Submitted February 16, 1998) I just heard the term 'hypernova'. Do hypernovae really exist? Is it true that there was a recently discovered one? How does a hypernova form, in contrast to supernovae & black holes? A hypernova is a possible explanation for gamma-ray bursts. It can be thought of as a "failed supernova" -...
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Questions, Suggestions, & References Back to Franklin Square QuestionsHere are some ideas for questions: Is it possible to make a Franklin Cube with some or all of the properties of the square? Which properties? Can some of the observations be combined to discover new magical or half-magical shapes? Can the constructio...
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If b>0 prove that limn->infinity 1/1+nb=0 using the limit definition. I can't seem to make any headway in choosing my delta to make progress in this exercise. what we need to do is show that for ANY ε > 0 (even, or perhaps especially the very tiny ones), we can find SOME positive integer N, such that: for ALL n > N: no...
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(a) AB = 8, BC = 6 in rectangle ABCD. Find the lengths of all segments shown in the diagram above. Specifically: BD, CF,DE, BE, FE, CE Comments: This is another in a series of rectangle investigations. To deepen student understanding of triangle relationships and to provide considerable practice with these ideas, the q...
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