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https://en.wikipedia.org/wiki/Asepsis | Asepsis is the state of being free from disease-causing micro-organisms (such as pathogenic bacteria, viruses, pathogenic fungi, and parasites). There are two categories of asepsis: medical and surgical. The modern day notion of asepsis is derived from the older antiseptic techniques, a shift initiated by different individuals in the 19th century who introduced practices such as the sterilizing of surgical tools and the wearing of surgical gloves during operations. The goal of asepsis is to eliminate infection, not to achieve sterility. Ideally, a surgical field is sterile, meaning it is free of all biological contaminants (e.g. fungi, bacteria, viruses), not just those that can cause disease, putrefaction, or fermentation. Even in an aseptic state, a condition of sterile inflammation may develop. The term often refers to those practices used to promote or induce asepsis in an operative field of surgery or medicine to prevent infection.
History
The modern concept of asepsis evolved in the 19th century through multiple individuals. Ignaz Semmelweis showed that hand washing prior to delivery reduced puerperal fever. Despite this, many hospitals continued to practice surgery in unsanitary conditions, with some surgeons taking pride in their bloodstained operating gowns. It was not until after reading of the findings by Louis Pasteur that Joseph Lister introduced the use of carbolic acid as an antiseptic, and in doing so, reduced surgical infection rates. Lawson Tait shifted the movement then from antisepsis to asepsis, instilling practices such as a strict no-talking policy within his operating room and drastically limiting the number of people to come in contact with a patient's wound. Ernst von Bergmann also introduced the autoclave, a device used for the practice of the sterilization of surgical instruments.
But, everything from operating room uniforms to gloves was pioneered by William Halsted. Preceding modern-day scrubs attire, Halsted implemented a no street c |
https://en.wikipedia.org/wiki/Coin%20problem | The coin problem (also referred to as the Frobenius coin problem or Frobenius problem, after the mathematician Ferdinand Frobenius) is a mathematical problem that asks for the largest monetary amount that cannot be obtained using only coins of specified denominations, for example, the largest amount that cannot be obtained using only coins of 3 and 5 units is 7 units. The solution to this problem for a given set of coin denominations is called the Frobenius number of the set. The Frobenius number exists as long as the set of coin denominations has no common divisor greater than 1.
There is an explicit formula for the Frobenius number when there are only two different coin denominations, and : the Frobenius number is then . If the number of coin denominations is three or more, no explicit formula is known. However, for any fixed number of coin denominations, there is an algorithm for computing the Frobenius number in polynomial time (in the logarithms of the coin denominations forming an input). No known algorithm is polynomial time in the number of coin denominations, and the general problem, where the number of coin denominations may be as large as desired, is NP-hard.
Statement
In mathematical terms, the problem can be stated:
Given positive integers such that gcd, find the largest integer that cannot be expressed as an integer conical combination of these numbers, i.e., as a sum:
where are non-negative integers.
This largest integer is called the Frobenius number of the set , and is usually denoted by
The existence of the Frobenius number depends on the condition that the greatest common divisor (GCD) is equal to 1. Indeed, the potential sums are multiples of the GCD in all cases. Hence, if it is not 1, then there are always arbitrarily large numbers that cannot be obtained as sums. For example, if you had two types of coins valued at 6 cents and 14 cents, the GCD would equal 2, and there would be no way to combine any number of such coins to produce a |
https://en.wikipedia.org/wiki/MBus%20%28SPARC%29 | MBus is a computer bus designed and implemented by Sun Microsystems for communication between high speed computer system components, such as the central processing unit, motherboard and main memory. SBus is used in the same machines to connect add-on cards to the motherboard.
MBus was first used in Sun's first multiprocessor SPARC-based system, the SPARCserver 600MP series (launched in 1991), and later found use in the SPARCstation 10 and SPARCstation 20 workstations. The bus permits the integration of several microprocessors on a single motherboard, in a multiprocessing configuration with up to eight CPUs packaged in detachable MBus modules. In practice, the number of processors per MBus is limited to four. Single processor systems were also sold that use the MBus protocol internally, but with the CPUs permanently attached to the motherboard to lower manufacturing costs.
MBus specifies a 64-bit datapath, which uses 36-bit physical addressing, giving an address space of 64 GB. The transfer rate is 80 MB/s sustained (320 MB/s peak) at 40 MHz, or 100 MB/s (400 MB/s peak) at 50 MHz. Bus controlling is done by an arbiter. Interrupt, reset, and timeout logic are also specified.
Related buses
Several related buses were also developed:
XBus
XBus is a packet-switched bus used in the SPARCserver 1000, SPARCcenter 2000 and Cray CS6400. This corresponds to the circuit-switched MBus, with identical electrical characteristics and physical form factor but an incompatible signalling protocol.
KBus
KBus is a high-speed interconnection system for linking multiple MBuses, used in Solbourne Computer Series 6 and Series 7 computer systems.
History
The MBus standard was cooperatively developed by Sun and Ross Technology and released in 1991.
Manufacturers who produced computer systems using the MBus included Sun, Ross Technology, Hyundai/Axil, Fujitsu, Solbourne Computer, Tatung, GCS, Auspex, ITRI, ICL, Cray, Amdahl, Themis, DTK and Kamstrup.
See also
List of device bandw |
https://en.wikipedia.org/wiki/Cicutoxin | Cicutoxin is a naturally-occurring poisonous chemical compound produced by several plants from the family Apiaceae including water hemlock (Cicuta species) and water dropwort (Oenanthe crocata). The compound contains polyene, polyyne, and alcohol functional groups and is a structural isomer of oenanthotoxin, also found in water dropwort. Both of these belong to the C17-polyacetylenes chemical class.
It causes death by respiratory paralysis resulting from disruption of the central nervous system. It is a potent, noncompetitive antagonist of the gamma-aminobutyric acid (GABA) receptor. In humans, cicutoxin rapidly produces symptoms of nausea, emesis and abdominal pain, typically within 60 minutes of ingestion. This can lead to tremors, seizures, and death. LD50(mouse; i.p.) ~9 mg/kg
History
Johann Jakob Wepfer's book Cicutae Aquaticae Historia Et Noxae Commentario Illustrata was published in 1679; it contains the earliest published report of toxicity associated with Cicuta plants. The name cicutoxin was coined by Boehm in 1876 for the toxic compound arising from the plant Cicuta virosa, and he also extracted and named the isomeric toxin oenanthotoxin from Oenanthe crocata. A review published in 1911 examined 27 cases of cicutoxin poisoning, 21 of which had resulted in death – though some of these cases involved deliberate poisoning. This review included a case where a family of five used Cicuta extracts as a topical treatment for itching, resulting in the deaths of two children, a report that suggests that cicutoxin may be absorbed through the skin. A review from 1962 examined 78 cases, 33 of which resulted in death, and cases of cicutoxin poisoning continue to occur:
A child used the stem of a plant as a toy whistle and died of cicutoxin poisoning
A 14-year-old boy died 20 hours after consuming a 'wild carrot' in 2001
In 1992, two brothers were foraging for wild ginseng and found a hemlock root. One of them ate three bites of the supposed ginseng root and |
https://en.wikipedia.org/wiki/Lehmer%20sequence | In mathematics, a Lehmer sequence is a generalization of a Lucas sequence.
Algebraic relations
If a and b are complex numbers with
under the following conditions:
Q and R are relatively prime nonzero integers
is not a root of unity.
Then, the corresponding Lehmer numbers are:
for n odd, and
for n even.
Their companion numbers are:
for n odd and
for n even.
Recurrence
Lehmer numbers form a linear recurrence relation with
with initial values . Similarly the companion sequence satisfies
with initial values |
https://en.wikipedia.org/wiki/Max%20Planck%20Institute%20for%20Biophysical%20Chemistry | The Max Planck Institute for Biophysical Chemistry (), also known as the Karl-Friedrich Bonhoeffer Institute (), was a research institute of the Max Planck Society, located in Göttingen, Germany. On January 1, 2022, the institute merged with the Max Planck Institute for Experimental Medicine in Göttingen to form the Max Planck Institute for Multidisciplinary Sciences.
This was the only Max Planck Institute (MPI) that combined the three classical scientific disciplines – biology, physics and chemistry. Founded in 1971, its initial focus was on problems in physics in chemistry. It had undergone a continuous evolution manifested through an expanding range of core subjects and work areas such as neurobiology, biochemistry, and molecular biology. At the time of merger, 850 people worked at the institute, about half of them scientists. Four researchers working at the institute – Stefan Hell, 2014; Erwin Neher and Bert Sakmann, 1991; and Manfred Eigen, 1967 – were awarded the Nobel Prize.
History
The origins of the institute date to 1949. At that time, the Max Planck Society established the MPI for Physical Chemistry in Göttingen as a follow-up to the former Kaiser Wilhelm Institute for Physical Chemistry in Berlin. Karl-Friedrich Bonhoeffer, who had worked at the Kaiser Wilhelm Institute, became the founding director of the new institute. He was one of the first researchers who applied physical-chemical methods in biological research and thus combined different disciplines of natural sciences in research.
In 1971, the MPI for Physical Chemistry merged with the MPI for Spectroscopy (also in Göttingen), forming the MPI for Biophysical Chemistry. This was mainly initiated by Nobel Prize laureate Manfred Eigen, director of the MPI for Physical Chemistry. His vision of an interdisciplinary approach to biological research was decisive and the creative impulse for the development of the institute. In honour of Karl Friedrich Bonhoeffer, the new institute was named after him |
https://en.wikipedia.org/wiki/Aggregate%20planning | Aggregate planning is a marketing activity that does an aggregate plan for the production process, in advance of 6 to 18 months, to give an idea to management as to what quantity of materials and other resources are to be procured and when, so that the total cost of operations of the organization is kept to the minimum over that period.
The quantity of outsourcing, subcontracting of items, overtime of labour, numbers to be hired and fired in each period and the amount of inventory to be held in stock and to be backlogged for each period are decided. All of these activities are done within the framework of the company ethics, policies, and long term commitment to the society, community and the country of operation.
Aggregate planning has certain pre-required inputs which are inevitable. They include:
Information about the resources and the facilities available.
Demand forecast for the period for which the planning has to be done.
Cost of various alternatives and resources. This includes cost of holding inventory, ordering cost, cost of production through various production alternatives like subcontracting, backordering and overtime.
Organizational policies regarding the usage of above alternatives.
"Aggregate Planning is concerned with matching supply and demand of output over the medium time range, up to approximately 12 months into the future. The term aggregate implies that the planning is done for a single overall measure of output or, at the most, a few aggregated product categories. The aim of aggregate planning is to set overall output levels in the near to medium future in the face of fluctuating or uncertain demands. Aggregate planning might seek to influence demand as well as supply.
Aggregate Plan Strategies
Level plans
Use a constant workforce & produce similar quantities each time period
Use inventories and back-orders to absorb demand peaks & valleys
Use inventories in better way to absorb the peak of demand and valleys
Chase plans
Minimize finish |
https://en.wikipedia.org/wiki/Version%206%20Unix | Sixth Edition Unix, also called Version 6 Unix or just V6, was the first version of the Unix operating system to see wide release outside Bell Labs. It was released in May 1975 and, like its direct predecessor, targeted the DEC PDP-11 family of minicomputers. It was superseded by Version 7 Unix in 1978/1979, although V6 systems remained in regular operation until at least 1985.
AT&T Corporation licensed Version 5 Unix to educational institutions only, but licensed Version 6 also to commercial users for $20,000, and it remained the most widely used version into the 1980s. An enhanced V6 was the basis of the first ever commercially sold Unix version, INTERACTIVE's IS/1. Bell's own PWB/UNIX 1.0 was also based on V6, where earlier (unreleased) versions were based on V4 and V5. Whitesmiths produced and marketed a (binary-compatible) V6 clone under the name Idris.
Source code
V6 Unix was released as a distribution including the full source code. Since source code was available and the license was not explicit enough to forbid it, V6 was taken up as a teaching tool, notably by the University of California, Berkeley, Johns Hopkins University and the University of New South Wales (UNSW).
UC Berkeley distributed a set of add-on programs called the First Berkeley Software Distribution or 1BSD, which later became a complete operating system distribution.
UNSW professor John Lions' famous Commentary on UNIX 6th Edition was an edited selection of the main parts of the kernel as implemented for a Digital PDP-11/40, and was the main source of kernel documentation for many early Unix developers. Due to license restrictions on later Unix versions, the book was mainly distributed by samizdat photo-copying.
The source code for the original V6 Unix was later made available as free software under a BSD License from the SCO Group.
Portability
Interdata 7/32
In 1977, Richard Miller and Ross Nealon, working under the supervision of professor Juris Reinfelds at Wollongong University |
https://en.wikipedia.org/wiki/Videotelephony | Videotelephony (also known as videoconferencing, video teleconferencing, or simply video call) is the two-way or multipoint reception and transmission of audio and video signals by people in different locations for real-time communication. A videophone is a telephone with a video camera and video display, capable of simultaneous video and audio communication. Videoconferencing implies the use of this technology for a group or organizational meeting rather than for individuals, in a videoconference. Telepresence may refer either to a high-quality videotelephony system (where the goal is to create the illusion that remote participants are in the same room) or to meetup technology, which can go beyond video into robotics (such as moving around the room or physically manipulating objects). Videoconferencing has also been called visual collaboration and is a type of groupware.
While development of video-conferring started in the late 19th century, the technology only became available to the public starting in the 1930s. These early demonstrations were installed at booths in post offices and shown at various world expositions. It took until 1970 for AT&T to launch the first true video-conferring system, where anyone could subscribe to the service and have the technology in their home or office. Videotelephony also included image phones which would exchange still images between units every few seconds over conventional plain old telephone service (POTS) lines, essentially the same as slow-scan TV. The development of advanced video codecs, more powerful CPUs, and high-bandwidth Internet service in the late 1990s allowed videophones to provide high-quality low-cost color service between users almost any place in the world where the Internet is available.
Useful applications include sign language transmission for deaf and speech-impaired people, distance education, telemedicine, and overcoming mobility issues. It is also used in commercial and corporate settings to facilita |
https://en.wikipedia.org/wiki/UDP%20hole%20punching | UDP hole punching is a commonly used technique employed in network address translation (NAT) applications for maintaining User Datagram Protocol (UDP) packet streams that traverse the NAT. NAT traversal techniques are typically required for client-to-client networking applications on the Internet involving hosts connected in private networks, especially in peer-to-peer, Direct Client-to-Client (DCC) and Voice over Internet Protocol (VoIP) deployments.
UDP hole punching establishes connectivity between two hosts communicating across one or more network address translators. Typically, third-party hosts on the public transit network are used to establish UDP port states that may be used for direct communications between the communicating hosts. Once port state has been successfully established and the hosts are communicating, port state may be maintained either by normal communications traffic, or in the prolonged absence thereof, by keep-alive packets, usually consisting of empty UDP packets or packets with minimal, non-intrusive content.
Overview
UDP hole punching is a method for establishing bidirectional UDP connections between Internet hosts in private networks using network address translators. The technique is not applicable in all scenarios or with all types of NATs, as NAT operating characteristics are not standardized.
Hosts with network connectivity inside a private network connected via a NAT to the Internet typically use the Session Traversal Utilities for NAT (STUN) method or Interactive Connectivity Establishment (ICE) to determine the public address of the NAT that its communications peers require. In this process another host on the public network is used to establish port mapping and other UDP port state that is assumed to be valid for direct communication between the application hosts. Since UDP state usually expires after short periods of time in the range of tens of seconds to a few minutes, and the UDP port is closed in the process, UDP hole pu |
https://en.wikipedia.org/wiki/NAT%20traversal | Network address translation traversal is a computer networking technique of establishing and maintaining Internet Protocol connections across gateways that implement network address translation (NAT).
NAT traversal techniques are required for many network applications, such as peer-to-peer file sharing and voice over IP.
Network address translation
Network address translation typically uses private IP addresses on private networks with a single public IP address for the router facing the Internet. The network address translator changes the source address in network protocols for outgoing requests from that of an internal device to its external address, so that internal devices can communicate with hosts on the external network, while relaying replies back to the originating device.
This leaves the internal network ill-suited for hosting services, as the NAT device has no automatic method for determining the internal host for which incoming packets from the external network are destined. This is not a problem for general web access and email. However, applications such as peer-to-peer file sharing, VoIP services, and video game consoles require clients to be servers as well. Incoming requests cannot be easily correlated to the proper internal host. Furthermore, many of these types of services carry IP address and port number information in the application data, potentially requiring substitution with deep packet inspection.
Network address translation technologies are not standardized. As a result, the methods used for NAT traversal are often proprietary and poorly documented. Many traversal techniques require assistance from servers outside of the masqueraded network. Some methods use the server only when establishing the connection, while others are based on relaying all data through it, which increases the bandwidth requirements and latency, detrimental to real-time voice and video communications.
NAT traversal techniques usually bypass enterprise security po |
https://en.wikipedia.org/wiki/Black%20Sun%20%28symbol%29 | The Black Sun () is a type of sun wheel (German: ) symbol originating in Nazi Germany and later employed by neo-Nazis and other far-right individuals and groups. The symbol's design consists of twelve radial sig runes, similar to the symbols employed by the SS in their logo. It first appeared in Nazi Germany as a design element in a castle at Wewelsburg remodeled and expanded by the head of the SS, Heinrich Himmler, which he intended to be a center for the SS.
It is unknown whether the design had a name or held any particular significance among the SS. Its association with the occult originates with a 1991 German novel, (The Black Sun of Tashi Lhunpo), by the pseudonymous author Russell McCloud. The book links the Wewelsburg mosaic with the neo-Nazi concept of the "Black Sun", invented by former SS officer Wilhelm Landig as a substitute for the Nazi swastika.
The Anti-Defamation League notes that though the symbol is popular with white supremacists, imagery resembling the black sun features in many cultures, and that such imagery should always be analyzed in the context in which it appears, as it may not necessarily be intended to serve as a symbol of white supremacy or racism.
Wewelsburg mosaic and the Nazi period
The symbol that later became known as the "black sun" originated in the early 20th century, with the first depiction being the Wewelsburg mosaic. In 1933, Heinrich Himmler, the head of the SS, acquired Wewelsburg, a castle near Paderborn in the German region of Westphalia. Himmler intended to make the building into a center for the SS, and between 1936 and 1942, Himmler ordered the building expanded and rebuilt for ceremonial purposes. Himmler's remodeling included the Wewelsburg mosaic that was composed of twelve dark-green radially overlaid sig runes, such as those employed in the logo of the SS, on the white marble floor of the structure's north tower known as the "General's Hall" (). The intended significance of the image remains unknown.
Some s |
https://en.wikipedia.org/wiki/Alethic%20modality | Alethic modality (from Greek ἀλήθεια = truth) is a linguistic modality that indicates modalities of truth, in particular the modalities of logical necessity, contingency, possibility and impossibility.
Alethic modality is often associated with epistemic modality in research, and it has been questioned whether this modality should be considered distinct from epistemic modality which denotes the speaker's evaluation or judgment of the truth. The criticism states that there is no real difference between "the truth in the world" (alethic) and "the truth in an individual's mind" (epistemic). An investigation has not found a single language in which alethic and epistemic modalities would be formally distinguished, for example by the means of a grammatical mood. In such a language, "A circle can't be square", "can't be" would be expressed by an alethic mood, whereas for "He can't be that wealthy", "can't be" would be expressed by an epistemic mood. As we can see, this is not a distinction drawn in English grammar.
"You can't give these plants too much water." is a well-known play on the distinction between perhaps alethic and hortatory or injunctive modalities (it can mean either "it is impossible to give these plants too much water = giving them too much water is harmless" or "you must not give these plants too much water = giving them too much water is harmful"). The dilemma is fairly easily resolved when listening through paralinguistic cues and particularly suprasegmental cues (intonation). So while there may not be a morphologically based alethic mood, this does not seem to preclude the usefulness of distinguishing between these two types of modes. Alethic modality might then concern what are considered to be apodictic statements. |
https://en.wikipedia.org/wiki/Optode | An optode or optrode is an optical sensor device that optically measures a specific substance usually with the aid of a chemical transducer.
Construction
An optode requires three components to function: a chemical that responds to an analyte, a polymer to immobilise the chemical transducer and instrumentation (optical fibre, light source, detector and other electronics). Optodes usually have the polymer matrix coated onto the tip of an optical fibre, but in the case of evanescent wave optodes the polymer is coated on a section of fibre that has been unsheathed.
Operation
Optodes can apply various optical measurement schemes such as reflection, absorption, evanescent wave, luminescence (fluorescence and phosphorescences), chemiluminescence, surface plasmon resonance. By far the most popular methodology is luminescence.
Luminescence in solution obeys the linear Stern–Volmer relationship. Fluorescence of a molecule is quenched by specific analytes, e.g., ruthenium complexes are quenched by oxygen. When a fluorophore is immobilised within a polymer matrix myriad micro-environments are created. The micro-environments reflect varying diffusion co-efficients for the analyte. This leads to a non-linear relationship between the fluorescence and the quencher (analyte). This relationship is modelled in various ways, the most popular model is the two site model created by James Demas (University of Virginia).
The signal (fluorescence) to oxygen ratio is not linear, and an optode is most sensitive at low oxygen concentration, i.e., the sensitivity decreases as oxygen concentration increases. The optode sensors can however work in the whole region 0–100% oxygen saturation in water, and the calibration is done the same way as with the Clark type sensor. No oxygen is consumed and hence the sensor is stirring insensitive, but the signal will stabilize more quickly if the sensor is stirred after being put into the sample.
Popularity
Optical sensors are growing in popularity due |
https://en.wikipedia.org/wiki/Free%20Software%20Foundation%20of%20India | The Free Software Foundation of India (FSFI) is the Indian sister organisation to the US-based Free Software Foundation. It was founded in Thiruvananthapuram (Trivandrum) (the capital of Kerala) in 2001 as a non-profit Company. The FSFI advocates to promote the use and development of free software in India. This includes educating people about free software, including how it can help the economy of a developing country like India. FSF India regards non-free software as not a solution, but a problem to be solved. Free software is sometimes locally called swatantra software in India.
In 2003, after meeting with FSF founder Richard Stallman, the President of India Dr. Abdul Kalam urged Indian computer scientists and professionals to use free and open-source software in research and development.
Logo
The left side of the FSF India logo resembles the famed Ashoka Chakra, that also appears on the Indian national flag, while its right half is a depiction of a compact disc. The combination of both symbols is intended to draw attention to the similarity between political freedom and free software, the latter of which the FSF promotes.
The Ashoka Chakra, in addition to being a long-standing Buddhist symbol depicting the wheel of time, also resembles Charkha of India's Freedom Struggle and thus in the current context, may symbolize the Indian independence movement which resulted in India's freedom from British occupation.
See also
Free Software Foundation
Free Software Foundation Europe
Free Software Movement of India
Free Software Movement |
https://en.wikipedia.org/wiki/Grid%20Security%20Infrastructure | The Grid Security Infrastructure (GSI), formerly called the Globus Security Infrastructure, is a specification for secret, tamper-proof, delegatable communication between software in a grid computing environment. Secure, authenticatable communication is enabled using asymmetric encryption.
Authentication
Authentication is performed using digital signature technology (see digital signatures for an explanation of how this works); secure authentication allows resources to lock data to only those who should have access to it.
Delegation
Authentication introduces a problem: often a service will have to retrieve data from a resource independent of the user; in order to do this, it must be supplied with the appropriate privileges. GSI allows for the creation of delegated privileges: a new key is created, marked as a delegated and signed by the user; it is then possible for a service to act on behalf of the user to fetch data from the resource.
Security mechanisms
Communications may be secured using a combination of methods:
Transport Layer Security (TLS) can be used to protect the communication channel from eavesdropping or man-in-the-middle attacks.
Message-Level Security can be used (although currently it is much slower than TLS). |
https://en.wikipedia.org/wiki/Nearline%20storage | Nearline storage (a portmanteau of "near" and "online storage") is a term used in computer science to describe an intermediate type of data storage that represents a compromise between online storage (supporting frequent, very rapid access to data) and offline storage/archiving (used for backups or long-term storage, with infrequent access to data).
Nearline storage dates back to the IBM 3850 Mass Storage System (MSS) tape library, which was announced in 1974.
Overview
The formal distinction between online, nearline, and offline storage is:
Online storage is immediately available for input/output (I/O).
Nearline storage is not immediately available, but can be made online quickly without human intervention.
Offline storage is not immediately available, and requires some human intervention to become online.
For example, always-on spinning hard disk drives are online storage, while spinning drives that spin down automatically, such as in Massive Arrays of Idle Disks (MAID), are nearline storage. Removable media such as tape cartridges that can be automatically loaded, as in tape libraries, are nearline storage, while tape cartridges that must be manually loaded are offline storage.
Robotic nearline storage
The nearline storage system knows on which volume (cartridge) the data resides, and usually asks a robot to retrieve it from this physical location (usually: a tape library or optical jukebox) and put it into a tape drive or optical disc drive to enable access by bringing the data it contains online. This process is not instant, but it only requires a few seconds.
Nearline tape and optical storage has the advantage of relatively longer lifespans compared to spinning hard drives, simply due to the storage media being idle and usually stored in protected dust-free enclosures when not in use. In a robotic tape loading system, the tape drive used for accessing data experiences the most wear and may need occasional replacement, but the tapes themselves can las |
https://en.wikipedia.org/wiki/CD8 | CD8 (cluster of differentiation 8) is a transmembrane glycoprotein that serves as a co-receptor for the T-cell receptor (TCR). Along with the TCR, the CD8 co-receptor plays a role in T cell signaling and aiding with cytotoxic T cell-antigen interactions.
Like the TCR, CD8 binds to a major histocompatibility complex (MHC) molecule, but is specific for the MHC class I protein.
There are two isoforms of the protein, alpha and beta, each encoded by a different gene. In humans, both genes are located on chromosome 2 in position 2p12.
Tissue distribution
The CD8 co-receptor is predominantly expressed on the surface of cytotoxic T cells, but can also be found on natural killer cells, cortical thymocytes, and dendritic cells. The CD8 molecule is a marker for cytotoxic T cell population. It is expressed in T cell lymphoblastic lymphoma and hypo-pigmented mycosis fungoides.
Structure
To function, CD8 forms a dimer, consisting of a pair of CD8 chains. The most common form of CD8 is composed of a CD8-α and CD8-β chain, both members of the immunoglobulin superfamily with an immunoglobulin variable (IgV)-like extracellular domain connected to the membrane by a thin stalk, and an intracellular tail. Less-common homodimers of the CD8-α chain are also expressed on some cells. The molecular weight of each CD8 chain is about 34 kDa. The structure of the CD8 molecule was determined by Leahy, D.J., Axel, R., and Hendrickson, W.A. by X-ray Diffraction at a 2.6A resolution. The structure was determined to have an immunoglobulin-like beta-sandwich folding and 114 amino acid residues. 2% of the protein is wound into α-helices and 46% into β-sheets, with the remaining 52% of the molecules remaining in the loop portions.
Function
The extracellular IgV-like domain of CD8-α interacts with the α3 portion of the Class I MHC molecule. This affinity keeps the T cell receptor of the cytotoxic T cell and the target cell bound closely together during antigen-specific activation. Cytotoxic T cel |
https://en.wikipedia.org/wiki/FitNesse | FitNesse is a web server, a wiki and an automated testing tool for software. It is based on Ward Cunningham's Framework for Integrated Test and is designed to support acceptance testing rather than unit testing in that it facilitates detailed readable description of system function.
FitNesse allows users of a developed system to enter specially formatted input (its format is accessible to non-programmers). This input is interpreted and tests are created automatically. These tests are then executed by the system and output is returned to the user. The advantage of this approach is very fast feedback from users. The developer of the system to be tested needs to provide some support (classes named "fixtures", conforming to certain conventions).
FitNesse is written in Java (by Micah Martin with help from Robert C. Martin and others). The program first supported only Java, but versions for several other languages have been added over time (C++, Python, Ruby, Delphi, C#, etc.).
Principles of FitNesse
FitNesse as a testing method
FitNesse was originally designed as a highly usable interface around the Fit framework. As such its intention is to support an agile style of black-box testing acceptance and regression testing. In this style of testing the functional testers in a software development project collaborate with the software developers to develop a testing suite.
FitNesse testing is based around the notation of black-box testing, in which a system under test is considered to be a black box and is tested in terms of the outputs generated in response to predetermined inputs. A functional tester is responsible for designing the tests in a functional sense and expressing them within the FitNesse tool, whereas the software developer is responsible for connecting the FitNesse tool to the system under test so that FitNesse can execute the test and compare the actual output to the expected output.
The idea behind this testing method, as described in Fit for Developing |
https://en.wikipedia.org/wiki/Masyu | is a type of logic puzzle designed and published by Nikoli. The purpose of its creation was to present a puzzle that uses no numbers or letters and yet retains depth and aesthetics.
Rules
Masyu is played on a rectangular grid of squares, some of which contain circles; each circle is either "white" (empty) or "black" (filled). The goal is to draw a single continuous non-intersecting loop that properly passes through all circled cells. The loop must "enter" each cell it passes through from the center of one of its four sides and "exit" from a different side; all turns are therefore 90 degrees.
The two varieties of circle have differing requirements for how the loop must pass through them:
White circles must be traveled straight through, but the loop must turn in the previous and/or next cell in its path.
Black circles must be turned upon, but the loop must travel straight through the next and previous cells in its path.
Variants
There are additionally or solely gray circles. The solver has to find out which of these gray circles are white and which are black.
The diagram is a Toroid; i.e. the left and the right edge of the diagram as well as the top and the bottom edge of the diagram are glued together.
The diagram is divided into regions; the loop must turn in every region at least once.
The diagram is played on a hexagonal grid, with grey circles indicating 60-degree turns where the loop turns both before and after the turn, and black circles indicating 120-degree turns where the loop goes straight on the cells before and after the turn.
History
The early version of Masyu first appeared in Puzzle Communication Nikoli #84 under the title of Shinju no Kubikazari (真珠の首飾り, meaning "pearl necklace"). That puzzle contains only white circles. Black circles were introduced in Puzzle Communication Nikoli #90, and the puzzle was renamed Shiroshinju Kuroshinju (白真珠黒真珠, meaning "white pearls and black pearls"). This improvement deepened the puzzle and made it gain po |
https://en.wikipedia.org/wiki/Crobots | Crobots is a programming game released for the first time by Tom Poindexter in December, 1985 as Shareware. It is an MS-DOS program for IBM PC and compatibles and was developed on x86-based Unix systems.
The robots are controlled by a program written in a stripped-down version of C. The robot's mission is to seek out and destroy other robots, each running different programs. The robots can be controlled in order to move around the battlefield, scan the environment to find enemies and fire at enemies using a cannon.
Crobots borrows the concept used from the game RobotWar that ran on the original Apple II computer. Robots were programmed in a proprietary programming language that was interpreted and included a real-time view of the game as it was played.
In October, 2013, Poindexter released the source code of Crobots under the GPLv2 free software license.
Clones
There have been many Crobots clones made. However, very few of them are compiler and virtual machine at the same time; for example there are Java clones that use JVM and C++ clones that use a standard Microsoft compiler.
Proper clones have the same intrinsic functions as the original Tom Poindexter version; sometimes however the direction of angles is changed to match the standard C library's trigonometric functions. The most recent clones are Crobots64 and Netrobots.
Crobots64 by Marco Zora has a C++-subset compiler and a virtual machine with a graphical interface. New capabilities in this clone are cooperation between robots of the same species, the unlimited number of concurrent robots, the floating point math functions and the speed of the virtual CPU.
In contrast, Netrobots can run over a network with each robot running in a separate process, and each robot can be written in a different programming language.
See also
Core War |
https://en.wikipedia.org/wiki/Simple%20Common%20Gateway%20Interface | The Simple Common Gateway Interface (SCGI) is a protocol for applications to interface with HTTP servers, as an alternative to the CGI protocol. It is similar to FastCGI but is designed to be easier to parse. Unlike CGI, it permits a long-running service process to continue serving requests, thus avoiding delays in responding to requests due to setup overhead (such as connecting to a database).
SCGI is a protocol which defines communication between a web server and an application server. This is in contrast to CGI, which is an earlier application (gateway) interface designed to let the application programmer avoid the complexity of sockets and long-running service processes when poor scalability and high overhead are acceptable.
The SCGI protocol leverages the fact that the web server has already parsed and validated the HTTP request, and canonically communicates the request to the SCGI server while letting the application programmer avoid parsing ambiguities and protocol edge cases. This avoids the complicated header-parsing and header-combining rules from RFC 2616, saving significant complexity in the SCGI server process.
History
Neil Schemenauer published the original SCGI protocol specification dated October 2001. He developed the first implementations of SCGI and initially published them in April 2002.
Specification
The client connects to a SCGI server over a reliable stream protocol allowing transmission of 8-bit bytes. The client begins by sending a request. When the SCGI server sees the end of the request it sends back a response and closes the connection. The format of the response is not specifically specified by this protocol, although CGI-equivalent HTTP responses are generally used.
Request format
A SCGI request is the concatenation of netstring-encoded headers and a body. A SCGI response is a normal HTTP response.
Each header consists of a name–value pair, where both the name and the value are null-terminated strings (C strings). The value ca |
https://en.wikipedia.org/wiki/Duck%20sauce | Duck sauce (or orange sauce) is a condiment with a sweet and sour flavor and a translucent orange appearance similar to a thin jelly. Offered at American Chinese restaurants, it is used as a dip for deep-fried dishes such as wonton strips, spring rolls, egg rolls, duck, chicken, fish, or with rice or noodles. It is often provided in single-serving packets along with soy sauce, mustard, hot sauce or red chili powder. It may be used as a glaze on foods, such as poultry. Despite its name, the sauce is not prepared using duck meat; rather it is named as such because it is a common accompaniment to Chinese-style duck dishes along with using duck in the sauce.
Ingredients
It is made of plums, apricots, pineapples or peaches added to sugar, vinegar, ginger and chili peppers. It is used in more traditional Chinese cuisine in the form of plum sauce.
Name
It is speculated that the name "duck sauce" came about because its ancestor, tianmian sauce, was first served with Peking duck in China. When the Chinese emigrated to the U.S., they created Chinese dishes that would appeal more to the American palate, and developed a sweeter version of the sauce used in China.
See also
List of dips
Hoisin sauce
List of condiments
List of sauces
Oyster sauce
Plum sauce
Siu haau sauce
Sweet and sour sauce
Tianmian sauce |
https://en.wikipedia.org/wiki/Image%20macro | An image macro is a piece of digital media featuring a picture, or artwork, with some form of text superimposed. The text frequently appears at the top and bottom of the image. Image macros were one of the most common forms of internet memes in the 2000s, and often featured witty messages or catchphrases, although not all image macros are necessarily humorous. LOLcats, which are images of expressive cats coupled with texts, are considered to be the first notable occurrence of image macros. Advice animal image macros, also referred to as stock-character macros, are also highly associated with the image macro template.
Etymology and use
The term "image macro" originated on the Something Awful forums. The name derived from the fact that the "macros" were a short bit of text a user could enter that the forum software would automatically parse and expand into the code for a pre-defined image. This, in turn, related to the computer science concept of a macroinstruction; "a rule or pattern that specifies how a certain input sequence (often a sequence of characters) should be mapped to an output sequence (also often a sequence of characters) according to a defined procedure".
Beginning in 2007, lolcats and similar image macros (a form of internet phenomenon) spread beyond the initial communities who created them and became widely popular.
Formats
Although they come in many forms, the most common type of image macros consists of:
Text, typically a large text in the Impact font, centered at the top and bottom of the image, usually using all upper-case letters. White text with a black border is typically used because it is easily readable on almost any background color. Typically, the text at the top is only for introduction and the text at the bottom is the main message. Exaggerated, intentional spelling errors are also used frequently for humorous effect.
An image to be placed behind the text. These are typically drawn from a specific set of images that are underst |
https://en.wikipedia.org/wiki/Virtual%20displacement | In analytical mechanics, a branch of applied mathematics and physics, a virtual displacement (or infinitesimal variation) shows how the mechanical system's trajectory can hypothetically (hence the term virtual) deviate very slightly from the actual trajectory of the system without violating the system's constraints. For every time instant is a vector tangential to the configuration space at the point The vectors show the directions in which can "go" without breaking the constraints.
For example, the virtual displacements of the system consisting of a single particle on a two-dimensional surface fill up the entire tangent plane, assuming there are no additional constraints.
If, however, the constraints require that all the trajectories pass through the given point at the given time i.e. then
Notations
Let be the configuration space of the mechanical system, be time instants, consists of smooth functions on , and
The constraints are here for illustration only. In practice, for each individual system, an individual set of constraints is required.
Definition
For each path and a variation of is a function such that, for every and The virtual displacement being the tangent bundle of corresponding to the variation assigns to every the tangent vector
In terms of the tangent map,
Here is the tangent map of where and
Properties
Coordinate representation. If are the coordinates in an arbitrary chart on and then
If, for some time instant and every then, for every
If then
Examples
Free particle in R3
A single particle freely moving in has 3 degrees of freedom. The configuration space is and For every path and a variation of there exists a unique such that as
By the definition,
which leads to
Free particles on a surface
particles moving freely on a two-dimensional surface have degree of freedom. The configuration space here is
where is the radius vector of the particle. It follows that
and every path ma |
https://en.wikipedia.org/wiki/Hypoplasia | Hypoplasia (from Ancient Greek 'under' + 'formation'; adjective form hypoplastic) is underdevelopment or incomplete development of a tissue or organ. Although the term is not always used precisely, it properly refers to an inadequate or below-normal number of cells. Hypoplasia is similar to aplasia, but less severe. It is technically not the opposite of hyperplasia (too many cells). Hypoplasia is a congenital condition, while hyperplasia generally refers to excessive cell growth later in life. (Atrophy, the wasting away of already existing cells, is technically the direct opposite of both hyperplasia and hypertrophy.)
Hypoplasia can be present in any tissue or organ. It is descriptive of many medical conditions, including underdevelopment of organs such as:
Breasts during puberty
Testes in Klinefelter's syndrome
Ovaries in Fanconi anemia, gonadal dysgenesis, trisomy X
Thymus in DiGeorge syndrome
Labia majora in popliteal pterygium syndrome
Corpus callosum, connecting the two sides of the brain, in agenesis of the corpus callosum
Cerebellum caused by mutation in the reelin gene
Tooth caused by oral pathology, such as Turner's hypoplasia
Chambers of the heart in hypoplastic left heart syndrome and hypoplastic right heart syndrome
Optic nerve in optic nerve hypoplasia
Sacrum in sacral agenesis
Facial muscle in asymmetric crying facies
Thumb from birth
Lungs, often as a result of oligohydramnios during gestation or the existence of congenital diaphragmatic hernia
Small bowel in coeliac disease
Fingers and ears in harlequin-type ichthyosis
Mandible in congenital hypothyroidism
See also
Atrophy, when an existing part wastes away
List of biological development disorders |
https://en.wikipedia.org/wiki/List%20of%20United%20Kingdom%20flags | This list includes flags that either have been in use or are currently used by the United Kingdom, British Overseas Territories and the Crown Dependencies.
The College of Arms is the authority on the flying of flags in England, Wales and Northern Ireland and maintains the only official register of flags for these countries. It was established in 1484 and as part of the Royal Household operates under the authority of the Crown. The Lord Lyon King of Arms, established prior to 1399, holds a similar role within Scotland. A separate private body called the Flag Institute, an educational charity financed by its own membership, also maintains a registry of United Kingdom flags that it styles 'the UK Flag Registry', though this has no official status under UK law.
Flags recognised by planning law
Certain classes of flag enjoy a special status within English planning law and can be flown without needing the planning permission normally required for advertisements. These include any country’s national flag, civil ensign or civil air ensign; the flag of the Commonwealth, the United Nations or any other international organisation of which the United Kingdom is a member; a flag of any island, county, district, borough, burgh, parish, city, town or village within the United Kingdom; the flag of the Black Country, East Anglia, Wessex, any Part of Lincolnshire, any Riding of Yorkshire or any historic county within the United Kingdom; the flag of St David; the flag of St Patrick; the flag of any administrative area within any country outside the United Kingdom; any flag of the British Armed Forces; and the Armed Forces Day flag.
Current national flags
National and subnational flags of the United Kingdom.
United Kingdom
Countries of the United Kingdom
The flags of England and of Scotland are ancient war flags which became by usage the national flags of the Kingdom of England (which included Wales) and of the Kingdom of Scotland respectively and continued in use until the Act o |
https://en.wikipedia.org/wiki/Rotations%20in%204-dimensional%20Euclidean%20space | In mathematics, the group of rotations about a fixed point in four-dimensional Euclidean space is denoted SO(4). The name comes from the fact that it is the special orthogonal group of order 4.
In this article rotation means rotational displacement. For the sake of uniqueness, rotation angles are assumed to be in the segment except where mentioned or clearly implied by the context otherwise.
A "fixed plane" is a plane for which every vector in the plane is unchanged after the rotation. An "invariant plane" is a plane for which every vector in the plane, although it may be affected by the rotation, remains in the plane after the rotation.
Geometry of 4D rotations
Four-dimensional rotations are of two types: simple rotations and double rotations.
Simple rotations
A simple rotation about a rotation centre leaves an entire plane through (axis-plane) fixed. Every plane that is completely orthogonal to intersects in a certain point . For each such point is the centre of the 2D rotation induced by in . All these 2D rotations have the same rotation angle .
Half-lines from in the axis-plane are not displaced; half-lines from orthogonal to are displaced through ; all other half-lines are displaced through an angle less than .
Double rotations
For each rotation of 4-space (fixing the origin), there is at least one pair of orthogonal 2-planes and each of which is invariant and whose direct sum is all of 4-space. Hence operating on either of these planes produces an ordinary rotation of that plane. For almost all (all of the 6-dimensional set of rotations except for a 3-dimensional subset), the rotation angles in plane and in plane – both assumed to be nonzero – are different. The unequal rotation angles and satisfying , are almost uniquely determined by . Assuming that 4-space is oriented, then the orientations of the 2-planes and can be chosen consistent with this orientation in two ways. If the rotation angles are unequal (), is sometimes |
https://en.wikipedia.org/wiki/Pulpitis | Pulpitis is inflammation of dental pulp tissue. The pulp contains the blood vessels, the nerves, and connective tissue inside a tooth and provides the tooth's blood and nutrients. Pulpitis is mainly caused by bacterial infection which itself is a secondary development of caries (tooth decay). It manifests itself in the form of a toothache.
Signs and symptoms
Increased sensitivity to stimuli, specifically hot and cold, is a common symptom of pulpitis. A prolonged throbbing pain may be associated with the disease. However, pulpitis can also occur without any pain.
Reversible pulpitis is characterised by intermittent, brief discomfort initiated by a hot, cold or sweet stimulus. The pain evoked is of short duration and there is no lingering or spontaneous pain. The pain ceases within a short period after removal of the stimulus. With a reversible pulpitis, sleep is usually not affected and no analgesics are necessary. Usually, no atypical change is evident on the radiograph. Pulp vitality tests are positive and it is possible to preserve a healthy vital pulp.
Irreversible pulpitis, in contrast, is characterised by a constant severe pain that arises without provocation. Characteristics may include sharp pain upon thermal stimulus, lingering thermal pain, spontaneity, and referred pain. Sometimes, the pain may be accentuated by postural changes such as lying down or bending over. If a stimulus is applied, the pain persists for minutes or hours after removal of the stimulus. These indicate that the vital inflamed pulp is not capable of healing and it is often indicated for the pulp to be removed as it is too damaged. Sleep may be disturbed and over-the-counter painkillers are often taken in an attempt to provide relief, but are usually ineffective.
Causes
Pulpitis may be caused by bacteria from dental caries that penetrate through the enamel and dentin to reach the pulp, or it may be mechanical, a result of trauma, such as physical damage to the tooth.
Inflammati |
https://en.wikipedia.org/wiki/Wizardry%3A%20Proving%20Grounds%20of%20the%20Mad%20Overlord | Wizardry: Proving Grounds of the Mad Overlord is the first game in the Wizardry series of role-playing video games. It was developed by Andrew Greenberg and Robert Woodhead. In 1980, Norman Sirotek formed Sir-Tech Software, Inc. and launched a beta version of the product at the 1980 Boston Computer Convention. The final version of the game was released in 1981.
The game was one of the first Dungeons & Dragons-style role-playing games to be written for computer play, and the first such game to offer color graphics. It was also the first true party-based role-playing video game. It is now listed among the best video games of all time.
The game ended up as the first of a trilogy that also included Wizardry II: The Knight of Diamonds and Wizardry III: Legacy of Llylgamyn.
Gameplay
Starting in the town, which is represented only as a text-based menu, the player creates a party of up to six characters from an assortment of five possible races (Humans, Elves, Dwarves, Gnomes, Hobbits), three alignments (Good, Neutral, Evil), and four basic classes (Fighter, Priest, Mage, Thief), with four elite classes (Bishop: priest and mage spells; Samurai: fighter with mage spells; Lord: fighter with priest spells, and Ninja: fighter with thief abilities) unlocked once the characters have progressed sufficiently. Good and evil characters normally cannot be assigned to the same party.
After characters are equipped with basic armor and weaponry, the party descends into the dungeon below Trebor's castle. This consists of a maze of ten levels, each progressively more challenging than the last. Classes have multiple spells, each with seven levels, that characters learn as they advance.
The style of play employed in this game has come to be termed a dungeon crawl. The goal, as in most subsequent role-playing video games, is to find treasure including ever more potent items, gain levels of experience by killing monsters, then face the evil arch-wizard Werdna on the bottom level and r |
https://en.wikipedia.org/wiki/The%20Fairyland%20Story | is a platform arcade video game developed and published by Taito in 1985. In the game, the player controls the witch Ptolemy, with the objective being to clear the screen of all enemies. Ptolemy can use her wand to turn the enemies into large cakes, which she can then push off of platforms onto other enemies, which will squash them and award bonus points. Various Items that increase Ptolemy's projectile radius, as well as kill multiple enemies at the same time, will also appear throughout the stages.
Gameplay has been compared to later Taito platform games, such as Bubble Bobble and The NewZealand Story. It has been ported to various home systems, and has seen releases in various Taito compilations.
Gameplay
The Fairyland Story is a platform arcade game. The player controls the witch Ptolemy through a series of single-screen stages, with the objective being to defeat all of the enemies on each screen. Ptolemy's main weapon is her projectile magic, which will temporarily transform the enemies into large cakes. While in a "caked" form, the enemies can be destroyed either by further magic attacks or by being dropped off a platform, possibly squashing other enemies below. Squashing more than one enemy results in an award of more points and, sometimes, in extra bonuses. 2000 points are awarded for squashing an enemy below a cake, with each additional enemy doubling the number of points awarded. If two or more enemies are killed at once in one spot, a coin will appear in that spot, which may be collected for additional points, and if more are collected, will multiply in points, so as long the player doesn't lose a life.
Ptolemy's enemies are based upon typical fantasy beings - these include Orcs, pig-like soldiers, Salamanders, dragon-like creatures that can breathe fire, Wizards, mages that can make Ptolemy shrink and disappear, Clerics, bishops who can multiply themselves, Golems, and Wraiths, hooded creatures can phase through Ptolemy's magic. If Ptolemy takes too |
https://en.wikipedia.org/wiki/Dollar%20sign | The dollar sign, also known as peso sign, is a currency symbol consisting of a capital "S" crossed with one or two vertical strokes ($ or depending on typeface), used to indicate the unit of various currencies around the world, including most currencies denominated "peso" and "dollar". The explicitly double-barred sign is called cifrão in Portuguese.
The sign is also used in several compound currency symbols, such as the Brazilian real (R$) and the United States dollar (US$): in local use, the nationality prefix is usually omitted. In countries that have other currency signs, the US dollar is often assumed and the "US" prefix omitted.
The one- and two-stroke version are often considered mere stylistic (typeface) variants, although in some places and epochs one of them may have been specifically assigned, by law or custom, to a specific currency. The Unicode computer encoding standard defines a single code for both.
In most English-speaking countries that use that symbol, it is placed to the left of the amount specified, e.g. "$1", read as "one dollar".
History
Use for the Spanish American peso in the late 1700s
The symbol appears in business correspondence in the 1770s from Spanish America, the early independent U.S., British America and Britain, referring to the Spanish American peso, also known as "Spanish dollar" or "piece of eight" in British America. Those coins provided the model for the currency that the United States adopted in 1792, and for the larger coins of the new Spanish American republics, such as the Mexican peso, Argentine peso, Peruvian real, and Bolivian sol coins.
With the Coinage Act of 1792, the United States Congress created the U.S. dollar, defining it to have "the value of a Spanish milled dollar as the same is now current" but a variety of foreign coins were deemed to be legal tender until the Coinage Act of 1857 ended this status.
The earliest U.S. dollar coins did not have any dollar symbol. The first occurrence in print is clai |
https://en.wikipedia.org/wiki/Idiosyncrasy | An idiosyncrasy is a particular feature of a person, though there are also other uses (see below). It usually means unique habits. The term is often used to express peculiarity. A synonym may be distinctive.
Etymology
The term "idiosyncrasy" originates from Greek , "a peculiar temperament, habit of body" (from , "one's own", , "with" and , "blend of the four humors" (temperament)) or literally "particular mingling".
Linguistics
The term can also be applied to symbols or words. Idiosyncratic symbols mean one thing for a particular person, as a blade could mean war, but to someone else, it could symbolize a surgery.
Idiosyncratic property
In phonology, an idiosyncratic property contrasts with a systematic regularity. While systematic regularities in the sound system of a language are useful for identifying phonological rules during analysis of the forms morphemes can take, idiosyncratic properties are those whose occurrence is not determined by those rules. For example, the fact that the English word cab starts with a /c/ is an idiosyncratic property; on the other hand that its vowel is longer than in the English word cap is a systematic regularity, as it arises from the fact that the final consonant is voiced rather than voiceless.
Medicine
Disease
Idiosyncrasy defined the way physicians conceived diseases in the 19th century. They considered each disease as a unique condition, related to each patient. This understanding began to change in the 1870s, when discoveries made by researchers in Europe permitted the advent of a "scientific medicine", a precursor to the evidence-based medicine that is the standard of practice today.
Pharmacology
The term idiosyncratic drug reaction denotes an aberrant or bizarre reaction or hypersensitivity to a substance, without connection to the pharmacology of the drug. It is what is known as a Type B reaction. Type B reactions have the following characteristics: they are usually unpredictable, might not be picked up by toxi |
https://en.wikipedia.org/wiki/Flipped%20SO%2810%29 | Flipped SO(10) is a grand unified theory which is to standard SO(10) as flipped SU(5) is to SU(5).
Details
In conventional SO(10) models, the fermions lie in three spinorial 16 representations, one for each generation, which decomposes under [SU(5) × U(1)χ]/Z5 as
This can either be the Georgi–Glashow SU(5) or flipped SU(5).
In flipped SO(10) models, however, the gauge group is not just SO(10) but SO(10)F × U(1)B or [SO(10)F × U(1)B]/Z4. The fermion fields are now three copies of
These contain the Standard Model fermions as well as additional vector fermions with GUT scale masses. If we suppose [SU(5) × U(1)A]/Z5 is a subgroup of SO(10)F, then we have the intermediate scale symmetry breaking [SO(10)F × U(1)B]/Z4 → [SU(5) × U(1)χ]/Z5 where
In that case,
note that the Standard Model fermion fields (including the right handed neutrinos) come from all three [SO(10)F × U(1)B]/Z4 representations. In particular, they happen to be the 101 of 161, the of 10−2 and the 15 of 14 (apologies to the readers for mixing up SO(10) × U(1) notation with SU(5) × U(1) notation, but it would be really cumbersome if we have to spell out which group any given notation happens to refer to. It is left up to the reader to determine the group from the context. This is a standard practice in the GUT model building literature anyway).
The other remaining fermions are vectorlike. To see this, note that with a 161H and a Higgs field, we can have VEVs which breaks the GUT group down to [SU(5) × U(1)χ]/Z5. The Yukawa coupling 161H 161 10−2 will pair up the 5−2 and fermions. And we can always introduce a sterile neutrino φ which is invariant under [SO(10) × U(1)B]/Z4 and add the Yukawa coupling
OR we can add the nonrenormalizable term
Either way, the 10 component of the fermion 161 gets taken care of so that it is no longer chiral.
It has been left unspecified so far whether [SU(5) × U(1)χ]/Z5 is the Georgi–Glashow SU(5) or the flipped SU(5). This is because both alternatives lead to reaso |
https://en.wikipedia.org/wiki/David%20M.%20Kreps | David Marc "Dave" Kreps (born 1950 in New York City) is a game theorist and economist and professor at the Graduate School of Business at Stanford University (since 1980). The Stanford University Department of Economics appointed Kreps the Adams Distinguished Professor of Management. He is known for his analysis of dynamic choice models and non-cooperative game theory, particularly the idea of sequential equilibrium, which he developed with Stanford Business School colleague Robert B. Wilson.
He earned his A.B. from Dartmouth College in 1972 and his Ph.D. from Stanford in 1975. Kreps won the John Bates Clark Medal in 1989. He was awarded an honorary Ph.D. by the Université Paris-Dauphine in 2001. With colleagues Paul Milgrom and Robert B. Wilson, he was awarded the 2018 John J. Carty Award for the Advancement of Science. He is a member of the National Academy of Sciences. In 2018, Kreps was awarded the Erwin Plein Nemmers Prize in Economics by Northwestern University.
He has also written many books, including Microeconomics for Managers, A Course in Microeconomic Theory, and Game Theory and Economic Modeling.
See also
Trade-off Talking Rational Economic Person
External links
David M. Kreps' home page at Stanford University |
https://en.wikipedia.org/wiki/Black%20bean%20paste | Black bean paste, commonly called dòushā () or hēidòushā (), is a sweet bean paste often used as a filling in cakes such as mooncakes or doushabao in many Chinese and Taiwanese cuisines.
Black bean paste is made from pulverized mung beans, combined with potassium chlorate, ferrous sulfate heptahydrate () crystal (which in Indonesia is known as tawas hijau, or "green crystal"), or black food colouring.
Black bean paste is similar to the more well-known red bean paste. The recorded history of black bean paste goes as far back as the Ming Dynasty. |
https://en.wikipedia.org/wiki/Oxyntomodulin | Oxyntomodulin (often abbreviated OXM) is a naturally occurring 37-amino acid peptide hormone found in the colon, produced by the oxyntic (fundic) cells of the oxyntic (fundic) mucosa. It has been found to suppress appetite.
The mechanism of action of oxyntomodulin is not well understood. It is known to bind both the GLP-1 receptor and the glucagon receptor, but it is not known whether the effects of the hormone are mediated through these receptors or through an unidentified receptor.
Oxyntomodulin has been linked to entrainment of the liver's circadian clock.
Oxyntomodulin has been investigated as a blood-glucose regulation agent in connection with diabetes.
Research
Oxyntomodulin could be a potential candidate for treating obesity because of its ability to suppress appetite. In a 4 week study, healthy overweight and obese volunteers were given either saline or oxyntomodulin injections. Their body weight, energy intake, and the levels of adipose hormones were taken prior to the treatment. The volunteers maintained their usual diets and daily activities and self-administered the injections three times daily, 30 minutes before their meals. In the course of 4 weeks, volunteers treated with oxyntomodulin injections had an average weight loss of 2.3±0.4 kg compared to those treated with saline who had an average of 0.5±0.5 kg, indicating oxyntomodulin was successful in weight loss. |
https://en.wikipedia.org/wiki/Profiling%20%28computer%20programming%29 | In software engineering, profiling ("program profiling", "software profiling") is a form of dynamic program analysis that measures, for example, the space (memory) or time complexity of a program, the usage of particular instructions, or the frequency and duration of function calls. Most commonly, profiling information serves to aid program optimization, and more specifically, performance engineering.
Profiling is achieved by instrumenting either the program source code or its binary executable form using a tool called a profiler (or code profiler). Profilers may use a number of different techniques, such as event-based, statistical, instrumented, and simulation methods.
Gathering program events
Profilers use a wide variety of techniques to collect data, including hardware interrupts, code instrumentation, instruction set simulation, operating system hooks, and performance counters.
Use of profilers
The output of a profiler may be:
A statistical summary of the events observed (a profile)
Summary profile information is often shown annotated against the source code statements where the events occur, so the size of measurement data is linear to the code size of the program.
/* ------------ source------------------------- count */
0001 IF X = "A" 0055
0002 THEN DO
0003 ADD 1 to XCOUNT 0032
0004 ELSE
0005 IF X = "B" 0055
A stream of recorded events (a trace)
For sequential programs, a summary profile is usually sufficient, but performance problems in parallel programs (waiting for messages or synchronization issues) often depend on the time relationship of events, thus requiring a full trace to get an understanding of what is happening.
The size of a (full) trace is linear to the program's instruction path length, making it somewhat impractical. A trace may therefore be initiated at one point in a |
https://en.wikipedia.org/wiki/The%20Research%20and%20Analysis%20Center | The Research and Analysis Center (TRAC), formerly the TRADOC Analysis Center, is an analysis agency of the United States Army. TRAC conducts research on potential military operations worldwide to inform decisions about the most challenging issues facing the Army and the Department of Defense (DoD). TRAC relies upon the intellectual capital of a highly skilled workforce of military and civilian personnel to execute its mission.
TRAC conducts operations research (OR) on a wide range of military topics, some contemporary but most often set five to 15 years in the future. TRAC directly supports the mission of the Army Futures Command (AFC), to develop future concepts and requirements while also serving the decision needs of many military clients.
Mission statement
To produce relevant and credible operations analysis to inform decisions.
Organization
TRAC is led by a civilian SES director, subordinate to the Commanding General of the US Army Futures Command. It comprises four centers:
TRAC-Fort Leavenworth (TRAC-FLVN), led by a civilian SES director, is co-located with TRAC headquarters at Fort Leavenworth, Kansas and has traditionally conducted analysis at the operational (Corps and division) level.
TRAC-White Sands Missile Range (TRAC-WSMR), led by a civilian SES director, is located at White Sands Missile Range in New Mexico and has traditionally conducted analysis at the tactical Brigade and below level.
TRAC-LEE, led by a led by a lieutenant colonel, is co-located with the Combined Arms Support Command (CASCOM) located at Fort Lee, VA and has traditionally conducted analysis in the area of Sustainment, which includes Logistics and other support functions such as medical and personnel.
TRAC-Monterey, also led by a lieutenant colonel, is co-located with the Naval Postgraduate School (NPS) in Monterey, CA and has traditionally utilized the resources of NPS to conduct research into new models and methodologies.
Each center director is subordinate to the TRA |
https://en.wikipedia.org/wiki/Radial%20basis%20function | In mathematics a radial basis function (RBF) is a real-valued function whose value depends only on the distance between the input and some fixed point, either the origin, so that , or some other fixed point , called a center, so that . Any function that satisfies the property is a radial function. The distance is usually Euclidean distance, although other metrics are sometimes used. They are often used as a collection which forms a basis for some function space of interest, hence the name.
Sums of radial basis functions are typically used to approximate given functions. This approximation process can also be interpreted as a simple kind of neural network; this was the context in which they were originally applied to machine learning, in work by David Broomhead and David Lowe in 1988, which stemmed from Michael J. D. Powell's seminal research from 1977.
RBFs are also used as a kernel in support vector classification. The technique has proven effective and flexible enough that radial basis functions are now applied in a variety of engineering applications.
Definition
A radial function is a function . When paired with a metric on a vector space a function is said to be a radial kernel centered at . A Radial function and the associated radial kernels are said to be radial basis functions if, for any set of nodes
Examples
Commonly used types of radial basis functions include (writing and using to indicate a shape parameter that can be used to scale the input of the radial kernel):
Approximation
Radial basis functions are typically used to build up function approximations of the form
where the approximating function is represented as a sum of radial basis functions, each associated with a different center , and weighted by an appropriate coefficient The weights can be estimated using the matrix methods of linear least squares, because the approximating function is linear in the weights .
Approximation schemes of this kind have been particularly used i |
https://en.wikipedia.org/wiki/Chuvash%20numerals | Chuvash numerals is an ancient numeral system from the Old Turkic script the Chuvash people used. (Modern Chuvash use Hindu-Arabic numerals.)
Those numerals originate from finger numeration. They look like Roman numerals, but larger numerals stay at the right side. It was possible to carve those numerals on wood. In some cases numerals were preserved until the beginning of the 20th century.
Examples |
https://en.wikipedia.org/wiki/Gauss%27s%20lemma%20%28polynomials%29 | In algebra, Gauss's lemma, named after Carl Friedrich Gauss, is a statement about polynomials over the integers, or, more generally, over a unique factorization domain (that is, a ring that has a unique factorization property similar to the fundamental theorem of arithmetic). Gauss's lemma underlies all the theory of factorization and greatest common divisors of such polynomials.
Gauss's lemma asserts that the product of two primitive polynomials is primitive (a polynomial with integer coefficients is primitive if it has 1 as a greatest common divisor of its coefficients).
A corollary of Gauss's lemma, sometimes also called Gauss's lemma, is that a primitive polynomial is irreducible over the integers if and only if it is irreducible over the rational numbers. More generally, a primitive polynomial has the same complete factorization over the integers and over the rational numbers. In the case of coefficients in a unique factorization domain , "rational numbers" must be replaced by "field of fractions of ". This implies that, if is either a field, the ring of integers, or a unique factorization domain, then every polynomial ring (in one or several indeterminates) over is a unique factorization domain. Another consequence is that factorization and greatest common divisor computation of polynomials with integers or rational coefficients may be reduced to similar computations on integers and primitive polynomials. This is systematically used (explicitly or implicitly) in all implemented algorithms (see Polynomial greatest common divisor and Factorization of polynomials).
Gauss's lemma, and all its consequences that do not involve the existence of a complete factorization remain true over any GCD domain (an integral domain over which greatest common divisors exist). In particular, a polynomial ring over a GCD domain is also a GCD domain. If one calls primitive a polynomial such that the coefficients generate the unit ideal, Gauss's lemma is true over every commut |
https://en.wikipedia.org/wiki/Gauss%27s%20lemma%20%28number%20theory%29 | Gauss's lemma in number theory gives a condition for an integer to be a quadratic residue. Although it is not useful computationally, it has theoretical significance, being involved in some proofs of quadratic reciprocity.
It made its first appearance in Carl Friedrich Gauss's third proof (1808) of quadratic reciprocity and he proved it again in his fifth proof (1818).
Statement of the lemma
For any odd prime let be an integer that is coprime to .
Consider the integers
and their least positive residues modulo . These residues are all distinct, so there are ( of them.
Let be the number of these residues that are greater than . Then
where is the Legendre symbol.
Example
Taking = 11 and = 7, the relevant sequence of integers is
7, 14, 21, 28, 35.
After reduction modulo 11, this sequence becomes
7, 3, 10, 6, 2.
Three of these integers are larger than 11/2 (namely 6, 7 and 10), so = 3. Correspondingly Gauss's lemma predicts that
This is indeed correct, because 7 is not a quadratic residue modulo 11.
The above sequence of residues
7, 3, 10, 6, 2
may also be written
−4, 3, −1, −5, 2.
In this form, the integers larger than 11/2 appear as negative numbers. It is also apparent that the absolute values of the residues are a permutation of the residues
1, 2, 3, 4, 5.
Proof
A fairly simple proof, reminiscent of one of the simplest proofs of Fermat's little theorem, can be obtained by evaluating the product
modulo p in two different ways. On one hand it is equal to
The second evaluation takes more work. If is a nonzero residue modulo , let us define the "absolute value" of to be
Since counts those multiples which are in the latter range, and since for those multiples, is in the first range, we have
Now observe that the values are distinct for . Indeed, we have
because is coprime to .
This gives = , since and are positive least residues. But there are exactly of them, so their values are a rearrangement of the integers . Therefore,
|
https://en.wikipedia.org/wiki/Parallel%20terraced%20scan | The parallel terraced scan is a multi-agent based search technique that is basic to cognitive architectures, such as Copycat, Letter-string, the Examiner, Tabletop, and others. It was developed by John Rehling and Douglas Hofstadter at the Center for Research on Concepts and Cognition at Indiana University, Bloomington.
The parallel terraced scan builds on the concepts of the workspace, coderack, conceptual memory, and temperature. According to Hofstadter the parallel and random nature of the processing captures aspects of human cognition.
See also
Copycat
External links
The Parallel Terraced Scan: An Optimization For An Agent-Oriented Architecture (pdf)
Cognitive architecture
Theory of computation |
https://en.wikipedia.org/wiki/Best-effort%20delivery | Best-effort delivery describes a network service in which the network does not provide any guarantee that data is delivered or that delivery meets any quality of service. In a best-effort network, all users obtain best-effort service. Under best-effort, network performance characteristics such as network delay and packet loss depend on the current network traffic load, and the network hardware capacity. When network load increases, this can lead to packet loss, retransmission, packet delay variation, and further network delay, or even timeout and session disconnect.
Best-effort can be contrasted with reliable delivery, which can be built on top of best-effort delivery (possibly without latency and throughput guarantees), or with virtual circuit schemes which can maintain a defined quality of service.
Network examples
Physical services
The postal service (snail mail) physically delivers letters using a best-effort delivery approach. The delivery of a certain letter is not scheduled in advance – no resources are preallocated in the post offices. The service will make their "best effort" to try to deliver a message, but the delivery may be delayed if too many letters suddenly arrive at a postal office or triage center. The sender is generally not informed when a letter has been delivered successfully, unless one pays for this premium service.
Conventional telephone networks are not based on best-effort communication, but on circuit switching. During the connection phase of a new call, resources are reserved in the telephone exchanges, or a busy signal informs the user that the call failed due to a lack of capacity. An ongoing phone call can never be interrupted due to overloading of the network, and is guaranteed constant bandwidth (both of which are not guaranteed in a mobile telephone network).
Internet
The Internet Protocol offers a best-effort service for delivering datagrams between hosts. IPv4 is a connectionless internet protocol that depends on the best |
https://en.wikipedia.org/wiki/Richard%20Turner%20%28computer%20scientist%29 | Richard Turner (born 1954) is a distinguished service professor in the School of Systems and Enterprises of Stevens Institute of Technology in Hoboken, New Jersey.
Turner has a BA in mathematics from Huntingdon College, an MS in computer science from the University of Louisiana-Lafayette, and a DSc in engineering management from the George Washington University.
Before joining Stevens, he was a Fellow of the Systems and Software Consortium Inc., a Research Professor at The George Washington University, a computer scientist at the Federal Aviation Administration, and technical manager and practitioner with various DC area businesses working with defense, intelligence, and commercial clients. He has also served as a visiting scientist at the Software Engineering Institute of Carnegie Mellon University, and consulted independently.
Much of his research at Stevens has been through the Systems Engineering Research Center (SERC) supporting the U.S. Department of Defense, particularly on the integration of systems and software engineering and the acquisition of complex defense systems. He was on the original author team of the CMMI and a core author of the Software Extension to the Guide to the Project Management Body of Knowledge PMI and IEEE Computer Society.
He is a Senior Member of the IEEE, a Golden Core Awardee of the IEEE Computer Society, and a Fellow of the Lean Systems Society.
He has authored / co authored several books:-
The Incremental Commitment Spiral Model: Principles and Practices for Successful Systems and Software, by Barry Boehm, Jo Ann Lane, Supannika Koolmanojwong, and Richard Turner: Addison-Wesley, (2014).
CMMI (Capability Maturity Model Integration) Distilled: A Practical Introduction to Integrated Process Improvement, by Dennis M. Ahern, Aaron Clouse, Richard Turner: Addison-Wesley, (Third Edition 2008).
CMMI Survival Guide: Just enough process improvement, by Suzanne Garcia, Richard Turner: Addison-Wesley, (2007).
Balancing Agility |
https://en.wikipedia.org/wiki/WMOR-TV | WMOR-TV (channel 32) is an independent television station licensed to Lakeland, Florida, United States, serving the Tampa Bay area. Owned by Hearst Television, the station maintains studios on Hillsborough Avenue in east Tampa, and its transmitter is located in Riverview. Master control and some internal operations are based at the studios of Orlando NBC affiliate WESH (channel 2) on North Wymore Road in Eatonville.
WMOR-TV is the only television station owned by Hearst that is not affiliated with any major broadcast network, as well as the only Hearst station that does not maintain a news department. Despite Lakeland being WMOR-TV's city of license, the station has no physical presence there.
History
The station first signed on the air on April 24, 1986, as WTMV; branded as "V-32", it originally maintained an all-music video format. The station's owner and general manager was Dan Johnson, former mayor of St. Petersburg Beach, who previously owned the old WXCR-FM classical music radio station in nearby Safety Harbor. The station originally operated from studio facilities located on South Florida Avenue/SR 37 on the south side of Lakeland, with its transmitter near Mulberry in southwestern Polk County.
After a brief period of broadcasting from its transmitter in Mulberry, WTMV relocated its studio operations to its present-day studios in Tampa in 1988. The facility had been a former headend office for Group W Cable's Hillsborough County system. Around this time, it transitioned to a conventional general entertainment format, filling a void left by WFTS-TV's switch to Fox. It aired a schedule of off-network and syndicated sitcoms and dramas, game shows, movies and cartoons. It also picked up several network programs from ABC, NBC and CBS that Tampa Bay's Big Three affiliates (WTSP channel 10 (now with CBS), WFLA-TV channel 8, and WTVT channel 13 (now with Fox)) as well as those from Orlando (WFTV channel 9, WESH, WCPX (now WKMG-TV), channel 6) chose to preempt.
WT |
https://en.wikipedia.org/wiki/Ventricular%20hypertrophy | Ventricular hypertrophy (VH) is thickening of the walls of a ventricle (lower chamber) of the heart. Although left ventricular hypertrophy (LVH) is more common, right ventricular hypertrophy (RVH), as well as concurrent hypertrophy of both ventricles can also occur.
Ventricular hypertrophy can result from a variety of conditions, both adaptive and maladaptive. For example, it occurs in what is regarded as a physiologic, adaptive process in pregnancy in response to increased blood volume; but can also occur as a consequence of ventricular remodeling following a heart attack. Importantly, pathologic and physiologic remodeling engage different cellular pathways in the heart and result in different gross cardiac phenotypes.
Presentation
In individuals with eccentric hypertrophy there may be little or no indication that hypertrophy has occurred as it is generally a healthy response to increased demands on the heart. Conversely, concentric hypertrophy can make itself known in a variety of ways. Most commonly, chest pain, either with or without exertion is present, along with shortness of breath with exertion, general fatigue, syncope, and palpitations. Overt signs of heart failure, such as edema, or shortness of breath without exertion are uncommon.
Physiology
The ventricles are the chambers in the heart responsible for pumping blood either to the lungs (right ventricle) or to the rest of the body (left ventricle). Ventricular hypertrophy may be divided into two categories: concentric hypertrophy and eccentric hypertrophy. These adaptations are related to how the cardiomyocyte contractile units, called sarcomeres, respond to stressors such as exercise or pathology. Concentric hypertrophy is a result of pressure overload on the heart, resulting in parallel sarcomerogenesis (addition of sarcomere units parallel to existing units). Eccentric hypertrophy is related to volume overload and leads to the addition of sarcomeres in series.
Concentric hypertrophy results from |
https://en.wikipedia.org/wiki/Endogenous%20retrovirus | Endogenous retroviruses (ERVs) are endogenous viral elements in the genome that closely resemble and can be derived from retroviruses. They are abundant in the genomes of jawed vertebrates, and they comprise up to 5–8% of the human genome (lower estimates of ~1%).
ERVs are a vertically inherited proviral sequence and a subclass of a type of gene called a transposon, which can normally be packaged and moved within the genome to serve a vital role in gene expression and in regulation. ERVs however lack most transposon functions, are typically not infectious and are often defective genomic remnants of the retroviral replication cycle. They are distinguished as germline provirus retroelements due to their integration and reverse-transcription into the nuclear genome of the host cell.
Researchers have suggested that retroviruses evolved from a type of transposon called a retrotransposon, a Class I element; these genes can mutate and instead of moving to another location in the genome they can become exogenous or pathogenic. This means that not all ERVs may have originated as an insertion by a retrovirus but that some may have been the source for the genetic information in the retroviruses they resemble. When integration of viral DNA occurs in the germ-line, it can give rise to an ERV, which can later become fixed in the gene pool of the host population.
Formation
The replication cycle of a retrovirus entails the insertion ("integration") of a DNA copy of the viral genome into the nuclear genome of the host cell. Most retroviruses infect somatic cells, but occasional infection of germline cells (cells that produce eggs and sperm) can also occur. Rarely, retroviral integration may occur in a germline cell that goes on to develop into a viable organism. This organism will carry the inserted retroviral genome as an integral part of its own genome—an "endogenous" retrovirus (ERV) that may be inherited by its offspring as a novel allele. Many ERVs have persisted in the g |
https://en.wikipedia.org/wiki/National%20research%20and%20education%20network | A national research and education network (NREN) is a specialised internet service provider dedicated to supporting the needs of the research and education communities within a country.
It is usually distinguished by support for a high-speed backbone network, often offering dedicated channels for individual research projects.
In recent years NRENs have developed many 'above the net' services.
List of NRENs by geographic area
East and Southern Africa
UbuntuNet Alliance for Research and Education Networking - the Alliance of NRENs of East and Southern Africa
Eb@le - DRC NREN
EthERNet - Ethiopian NREN
iRENALA - Malagasy NREN
KENET - Kenyan NREN
MAREN - Malawian NREN
MoRENet - Mozambican NREN
RENU - Ugandan NREN
RwEdNet - Rwanda NREN
SomaliREN - Somali NREN
SudREN - Sudanese NREN
TENET/SANReN - South African NREN
TERNET - Tanzanian NREN
Xnet - Namibian NREN
ZAMREN - Zambian NREN
North Africa
ASREN - Arab States Research and Education Network
TUREN - Tunisian NREN
MARWAN - Moroccan NREN
ENREN - Egyptian NREN
ARN (Algeria) - Algerian NREN
SudREN - Sudanese NREN
SomaliREN - Somali NREN
West and Central Africa
WACREN - West and Central African Research and Education Network
GARNET - Ghanaian NREN
TogoRER - Togolese NREN
GhREN - Ghanaian NREN
MaliREN - Mali NREN
Niger-REN - Nigerien NREN
RITER - Côte d'Ivoire NREN
SnRER - Senegalese NREN
NgREN - Nigerian NREN
Eko-Konnect Research and Education Network - Nigerian NREN
LRREN - Liberia Research and Education Network
Asia Pacific
APAN - Asia-Pacific Advanced Network
AARNet - Australian NREN
AfgREN - Afghanistan NREN
BDREN - Bangladeshi NREN
CSTNET - China Science and Technology Network
CERNET - China Education and Research Network
ERNET - Indian NREN
HARNET - Hong Kong NREN
KOREN - Korean NREN
KREONET- Korean NREN
IDREN - Indonesian NREN
LEARN - Sri Lankan NREN
SINET - Japanese NREN
MYREN - Malaysian NREN
NKN - Indian NREN
NREN - Nepal NREN
NREN - Islamic Republic of Iran N |
https://en.wikipedia.org/wiki/UEFI%20Forum | UEFI Forum, Inc. is an alliance between technology companies to coordinate the development of the UEFI specifications. The board of directors includes representatives from twelve promoter companies: AMD, American Megatrends, ARM, Apple, Dell, Hewlett Packard Enterprise, HP Inc., Insyde Software, Intel, Lenovo, Microsoft, and Phoenix Technologies.
Overview
The non-profit corporation has assumed responsibility for the management and promotion of the Unified Extensible Firmware Interface (UEFI) specification, a bootloader and runtime interface between platform firmware and an operating system. The original EFI specification was developed by Intel and was used as the starting point from which the UEFI version(s) were developed. The goal of the organization is to replace the aging PC BIOS.
In addition to the UEFI specification, the forum is responsible for a UEFI Platform Initialization (PI) specification, which addresses the firmware internal architecture as well as firmware-to-hardware interfaces. The forum also is responsible for Self-Certification Test suites, which defines conformance to the specifications that it defines.
In October 2013, the Advanced Configuration and Power Interface (ACPI) assets have also been transferred into the forum. The forum is responsible for the management and promotion of future ACPI specifications, which provides static tables at boot time and dynamic control methods as the primary runtime interfaces between the OS and system firmware for system configuration, power management and RAS (Reliability, Availability and Supportability) features. ACPI "Revision 5.0" is used as the starting point from which future ACPI version(s) will be developed.
Published specifications
UEFI Specification version 2.8, published March, 2019
UEFI Shell Specification version 2.2, published January 26, 2016
UEFI Platform Initialization Specification version 1.7, published January, 2019
UEFI Platform Initialization Distribution Packaging Specification |
https://en.wikipedia.org/wiki/Electropherogram | An electropherogram, or electrophoretogram, can also be referred to as an EPG or e-gram. It is a record or chart produced when electrophoresis is used in an analytical technique, primarily in the fields of forensic biology, molecular biology and biochemistry. The method utilizes data points that correspond with a specific time and fluorescence intensity at various wavelengths of light to represent a DNA profile.
In the field of genetics, an electropherogram is a plot of DNA fragment sizes, typically used for genotyping such as DNA sequencing. The data is plotted with time, shown via base pairs (bps), on the x-axis and fluorescence intensity on the y-axis. Such plots are often achieved using an instrument such as an automated DNA sequencer paired with capillary electrophoresis (CE). Such electropherograms may be used to determine DNA sequence genotypes, or genotypes that are based on the length of specific DNA fragments or number of short tandem repeats (STR) at a specific locus by comparing the sample to internal size standards and allelic ladder data using the same size standard. These genotypes can be used for:
genealogical DNA testing
DNA paternity testing
DNA profiling
phylogenetics
population genetics
See also
Gel electrophoresis of nucleic acids |
https://en.wikipedia.org/wiki/Investigational%20device%20exemption | An investigational device exemption (IDE) allows an investigational device (i.e. a device that is the subject of a clinical study) to be used in order to collect safety and effectiveness data required to support a premarket approval (PMA) application or a
premarket notification [510(k)] submission to Food and Drug Administration (FDA). Clinical studies are most often conducted to support a PMA. Only a small percentage of 510(k)'s require clinical data to support the application. Investigational use also includes clinical evaluation of certain modifications or new intended uses of legally marketed devices. All clinical evaluations of investigational devices, unless exempt, must have an approved IDE before the study is initiated.
Clinical evaluation of devices that have not been cleared for marketing requires:
An IDE approved by an institutional review board (IRB). If the study involves a significant risk device, the IDE must also be approved by FDA
Informed consent from all patients
Labeling for investigational use only
Monitoring of the study and
Required records and reports
An approved IDE permits a device to be shipped lawfully for the purpose of conducting investigations of the device without complying with other requirements of the Food, Drug, and Cosmetic Act that would apply to devices in commercial distribution. Sponsors need not submit a PMA or premarket notification, register their establishment, or list the device while the device is under investigation. Sponsors of IDEs are also exempt from the Quality System (QS) Regulation except for the requirements for design control.
A commercial sponsor of a significant risk device study must submit a complete IDE application to FDA. There are no preprinted forms for an IDE application; however, an IDE application must include certain required information. The sponsor must demonstrate in the application that there is reason to believe that the risks to human subjects from the proposed investigation are outweighe |
https://en.wikipedia.org/wiki/Bioprocess | A bioprocess is a specific process that uses complete living cells or their components (e.g., bacteria, enzymes, chloroplasts) to obtain desired products.
Transport of energy and mass is fundamental to many biological and environmental processes. Areas, from food processing (including brewing beer) to thermal design of buildings to biomedical devices, manufacture of monoclonal antibodies to pollution control and global warming, require knowledge of how energy and mass can be transported through materials (momentum, heat transfer, etc.).
Cell bioprocessing
Cell therapy bioprocessing is a discipline that bridges the fields of cell therapy and bioprocessing (i.e., biopharmaceutical manufacturing), and is a sub-field of bioprocess engineering. The goals of cell therapy bioprocessing are to establish reproducible and robust manufacturing processes for the production of therapeutic cells. Commercially relevant bioprocesses will:
Produce products that maintain all of the quality standards of biopharmaceutical drugs
Supply both clinical and commercial quantities of therapeutic cells throughout the various stages of development. The processes and production technologies must be scalable, and
Control the cost of goods (CoGs) of the final drug product. This aspect is critical to building the foundation for a commercially viable industry.
Upstream bioprocessing
Therapeutic cell manufacturing processes can be separated into upstream processes and downstream processes. The upstream process is defined as the entire process from early cell isolation and cultivation, to cell banking and culture expansion of the cells until final harvest (termination of the culture and collection of the live cell batch).
Aside from technology challenges, concerning the scalability of culture apparatus, a number of raw material supply risks have emerged in recent years, including the availability of GMP grade fetal bovine serum.
The upstream part of a bioprocess refers to the first step |
https://en.wikipedia.org/wiki/INDICARE |
Goal
The overall goal of INDICARE (The INformed DIalogue about Consumer Acceptability of DRM Solutions in Europe) was to help to reconcile heterogeneous interests of multiple stakeholders, and to support the emergence of a common European position with regard to consumer and user issues of Digital Rights Management (DRM) solutions.
eContent
INDICARE responded to the 3rd call, subline 3.3: Management of rights for digital content, of the eContent Programme of the European Commission, DG Information Society. INDICARE, a so-called Accompanying Measure, was initiated March 2004 and was scheduled for two years (Ref.: EDC - 53042 INDICARE / 28609). eContent was replaced by eContentplus as of 9 March 2005.
Focus
INDICARE addresses problems pointed out in the eContent Work Programme 2003–2004: “There has been little attention to the consumer side of managing rights. Questions remain open as to the level of consumer acceptability of rights management solutions. Interface and functionality of systems, as well as policy issues linked to privacy and access to information should be the investigated. The consumer question also involves the easiness of access, the legitimate use of content and business models and the easiness of access for disabled persons” (p. 19). In addition to consumer issues, INDICARE addresses the user side, in particular concerns of creators and small and medium-sized information providers.
Approach
The INDICARE project establishes and maintains an informed dialogue about consumer and user issues of DRM. Informed dialogue means that discussions will be stimulated and informed by good quality input such as news information and profound analyses (see below). Part of the input will be derived from interdisciplinary in-depth research of the INDICARE partners as well as from knowledge of experts and stakeholders co-operating with INDICARE.
External links
INDICARE website with all publications
eContent Work Programme 2003–2004
eContentplus
Projec |
https://en.wikipedia.org/wiki/Nerve%20growth%20factor | Nerve growth factor (NGF) is a neurotrophic factor and neuropeptide primarily involved in the regulation of growth, maintenance, proliferation, and survival of certain target neurons. It is perhaps the prototypical growth factor, in that it was one of the first to be described. Since it was first isolated by Nobel Laureates Rita Levi-Montalcini and Stanley Cohen in 1956, numerous biological processes involving NGF have been identified, two of them being the survival of pancreatic beta cells and the regulation of the immune system.
Structure
NGF is initially in a 7S, 130-kDa complex of 3 proteins – Alpha-NGF, Beta-NGF, and Gamma-NGF (2:1:2 ratio) when expressed. This form of NGF is also referred to as proNGF (NGF precursor). The gamma subunit of this complex acts as a serine protease, and cleaves the N-terminal of the beta subunit, thereby activating the protein into functional NGF.
The term nerve growth factor usually refers to the 2.5S, 26-kDa beta subunit of the protein, the only component of the 7S NGF complex that is biologically active (i.e. acting as a signaling molecule).
Function
As its name suggests, NGF is involved primarily in the growth, as well as the maintenance, proliferation, and survival of nerve cells (neurons). In fact, NGF is critical for the survival and maintenance of sympathetic and sensory neurons, as they undergo apoptosis in its absence. However, several recent studies suggest that NGF is also involved in pathways besides those regulating the life cycle of neurons.
Neuronal proliferation
NGF can drive the expression of genes such as bcl-2 by binding to the Tropomyosin receptor kinase A, which stimulates the proliferation and survival of the target neuron.
High affinity binding between proNGF, sortilin, and p75NTR can result in either survival or programmed cell death. Study results indicate that superior cervical ganglia neurons that express both p75NTR and TrkA die when treated with proNGF, while NGF treatment of these same neuro |
https://en.wikipedia.org/wiki/Direct-attached%20storage | Direct-attached storage (DAS) is digital storage directly attached to the computer accessing it, as opposed to storage accessed over a computer network (i.e. network-attached storage). DAS consists of one or more storage units such as hard drives, solid-state drives, optical disc drives within an external enclosure. The term "DAS" is a retronym to contrast with storage area network (SAN) and network-attached storage (NAS).
Features
A typical DAS system is made of a data storage device (for example enclosures holding a number of hard disk drives) connected directly to a computer through a host bus adapter (HBA). Between those two points there is no network device (like hub, switch, or router), and this is the main characteristic of DAS.
The main protocols used for DAS connections are ATA, SATA, eSATA, NVMe, SCSI, SAS, USB, USB 3.0 and IEEE 1394.
Storage features of SAN, DAS, and NAS
Most functions found in modern storage do not depend on whether the storage is attached directly to servers (DAS), or via a network (SAN and NAS). In enterprise environments, direct-attached storage systems can utilize storage devices that have higher endurance in terms of data workload capability, along with scalability in the amount of capacity that storage arrays can achieve compared to NAS and other consumer-graded storage devices.
Advantages and disadvantages
The key difference between DAS and NAS is that DAS storage does not incorporate any network hardware and related operating environment to provide a facility to share storage resources independently of the host so is only available via the host to which the DAS is attached.
DAS is typically considered much faster than NAS due to lower latency in the type of host connection although contemporary network and direct connection throughput typically exceeds the raw read/write performance of the storage units themselves.
A SAN (storage area network) has more in common with a DAS than a NAS with the key difference being that DA |
https://en.wikipedia.org/wiki/Event%20reconstruction | In a particle detector experiment, event reconstruction is the process of interpreting the electronic signals produced by the detector to determine the original particles that passed through, their momenta, directions, and the primary vertex of the event. Thus the initial physical process (for instance, that occurred at the interaction point of the particle accelerator), whose study is the ultimate goal of the experiment, can be determined. The total event reconstruction is not always possible and necessary; in some cases, only a part of the data described above is obtained and processed.
Experimental particle physics |
https://en.wikipedia.org/wiki/Cognitive%20ethology | Cognitive ethology is a branch of ethology concerned with the influence of conscious awareness and intention on the behaviour of an animal. Donald Griffin, a zoology professor in the United States, set up the foundations for researches in the cognitive awareness of animals within their habitats.
The fusion of cognitive science and classical ethology into cognitive ethology "emphasizes observing animals under more-or-less natural conditions, with the objective of understanding the evolution, adaptation (function), causation, and development of the species-specific behavioral repertoire" (Niko Tinbergen 1963).
According to Jamieson & Bekoff (1993), "Tinbergen's four questions about the evolution, adaptation, causation and development of behavior can be applied to the cognitive and mental abilities of animals." Allen & Bekoff (1997, chapter 5) attempt to show how cognitive ethology can take on the central questions of cognitive science, taking as their starting point the four questions described by Barbara Von Eckardt in her 1993 book What is Cognitive Science?, generalizing the four questions and adding a fifth. Kingstone, Smilek & Eastwood (2008) suggested that cognitive ethology should include human behavior. They proposed that researchers should firstly study how people behave in their natural, real world environments and then move to the lab. Anthropocentric claims for the ways non-human animals interact in their social and non-social worlds are often used to influence decisions on how the non-human animals can or should be used by humans.
Relation to laboratory experimental psychology
Traditionally, cognitive ethologists have questioned research methods that isolate animals in unnatural surroundings and present them with a limited set of artificial stimuli, arguing that such techniques favor the study of artificial issues that are not relevant to an understanding of the natural behavior of animals. However, many modern researchers favor a judicious combinat |
https://en.wikipedia.org/wiki/Hopanoids | Hopanoids are a diverse subclass of triterpenoids with the same hydrocarbon skeleton as the compound hopane. This group of pentacyclic molecules therefore refers to simple hopenes, hopanols and hopanes, but also to extensively functionalized derivatives such as bacteriohopanepolyols (BHPs) and hopanoids covalently attached to lipid A.
The first known hopanoid, hydroxyhopanone, was isolated by two chemists at The National Gallery, London working on the chemistry of dammar gum, a natural resin used as a varnish for paintings. While hopanoids are often assumed to be made only in bacteria, their name actually comes from the abundance of hopanoid compounds in the resin of plants from the genus Hopea. In turn, this genus is named after John Hope, the first Regius Keeper of the Royal Botanic Garden, Edinburgh.
Since their initial discovery in an angiosperm, hopanoids have been found in plasma membranes of bacteria, lichens, bryophytes, ferns, tropical trees and fungi. Hopanoids have stable polycyclic structures that are well-preserved in petroleum reservoirs, rocks and sediment, allowing the diagenetic products of these molecules to be interpreted as biomarkers for the presence of specific microbes and potentially for chemical or physical conditions at the time of deposition. Hopanoids have not been detected in archaea.
Biological function
About 10% of sequenced bacterial genomes have a putative shc gene encoding a squalene-hopene cyclase and can presumably make hopanoids, which have been shown to play diverse roles in the plasma membrane and may allow some organisms to adapt in extreme environments.
Since hopanoids modify plasma membrane properties in bacteria, they are frequently compared to sterols (e.g., cholesterol), which modulate membrane fluidity and serve other functions in eukaryotes. Although hopanoids do not rescue sterol deficiency, they are thought to increase membrane rigidity and decrease permeability. Also, gammaproteobacteria and eukaryotic organisms |
https://en.wikipedia.org/wiki/In%20situ%20hybridization | In situ hybridization (ISH) is a type of hybridization that uses a labeled complementary DNA, RNA or modified nucleic acids strand (i.e., probe) to localize a specific DNA or RNA sequence in a portion or section of tissue (in situ) or if the tissue is small enough (e.g., plant seeds, Drosophila embryos), in the entire tissue (whole mount ISH), in cells, and in circulating tumor cells (CTCs). This is distinct from immunohistochemistry, which usually localizes proteins in tissue sections.
In situ hybridization is used to reveal the location of specific nucleic acid sequences on chromosomes or in tissues, a crucial step for understanding the organization, regulation, and function of genes. The key techniques currently in use include in situ hybridization to mRNA with oligonucleotide and RNA probes (both radio-labeled and hapten-labeled), analysis with light and electron microscopes, whole mount in situ hybridization, double detection of RNAs and RNA plus protein, and fluorescent in situ hybridization to detect chromosomal sequences. DNA ISH can be used to determine the structure of chromosomes. Fluorescent DNA ISH (FISH) can, for example, be used in medical diagnostics to assess chromosomal integrity. RNA ISH (RNA in situ hybridization) is used to measure and localize RNAs (mRNAs, lncRNAs, and miRNAs) within tissue sections, cells, whole mounts, and circulating tumor cells (CTCs). In situ hybridization was invented by American biologists Mary-Lou Pardue and Joseph G. Gall.
Challenges of in-situ hybridization
In situ hybridization is a powerful technique for identifying specific mRNA species within individual cells in tissue sections, providing insights into physiological processes and disease pathogenesis. However, in situ hybridization requires that many steps be taken with precise optimization for each tissue examined and for each probe used. In order to preserve the target mRNA within tissues, it is often required that crosslinking fixatives (such as formaldehyde |
https://en.wikipedia.org/wiki/Lexra | Lexra (1997–2003) was a semiconductor intellectual property core company based in Waltham, Massachusetts. Lexra developed and licensed semiconductor intellectual property cores that implemented the MIPS I architecture, except for the four unaligned load and store (lwl, lwr, swl, swr) instructions.
Lexra did not implement those instructions because they are not necessary for good performance in modern software. Silicon Graphics owned a patent that was initially granted to MIPS Computer Systems Inc. for implementing unaligned loads and stores in a RISC processor. Lexra did not wish to pay a high license fee for permission to use the patent.
Lexra licensed soft cores, unlike ARM Ltd at the time. Lexra was probably the first semiconductor intellectual property core company to do so.
In 1998 Silicon Graphics spun out MIPS Technologies Inc. as a semiconductor IP licensing company that would compete directly with Lexra. MIPS Technologies soon sued Lexra, asserting trademark infringement by Lexra's claims of compatibility with MIPS I. Lexra and MIPS Technologies settled the dispute by agreeing that Lexra would explicitly describe its products as not implementing unaligned loads and stores.
In 1999, MIPS Technologies sued Lexra again, but this time for infringing its patents on unaligned loads and stores. Though Lexra's processor designs did not implement unaligned loads and stores, it was possible to emulate their functionality through a series of other instructions. The ability to emulate the function of unaligned loads and stores was used, for example, in microcode for IBM mainframes long before the application for MIPS Technologies' patent. Lexra contended that the patent was invalid if construed to cover software emulation of unaligned loads and stores. If construed to cover only hardware implementations, Lexra did not infringe. The protracted second lawsuit, combined with a downturn in semiconductor industry business, forced Lexra into a settlement with MIPS Techno |
https://en.wikipedia.org/wiki/Michel%20de%20Castelnau | Michel de Castelnau, Sieur de la Mauvissière (c. 1520–1592) was a French soldier and diplomat, ambassador to Queen Elizabeth. He wrote a memoir covering the period between 1559 and 1570.
Life
He was born in La Mauvissière (now part of Neuvy-le-Roi, Indre-et-Loire), Touraine about 1520. He was a son of Jean de Castelnau and Jeanne Dusmesnil, one of a family of nine children. His grandfather, Pierre de Castelnau, had been Equerry (Master of the Horse) to Louis XII.
Endowed with a clear and penetrating intellect and remarkable strength of memory, he received a careful education, capped off with travels in Italy and a long stay at Rome. He then spent some time in Malta and afterwards entered the army. His first acquaintance with war was in the campaigns of the French in Italy. His abilities and his courage won him the friendship and protection of Charles, Cardinal of Lorraine, who took him into his service.
In 1557 a command in the navy was given to him, and the cardinal proposed to get him knighted. This, however, he declined, and then rejoined the French army in Picardy. Various delicate missions requiring tact and discretion were entrusted to him by the Constable, Anne de Montmorency, and these he discharged so satisfactorily that he was sent by the king, Henry II, to Scotland with dispatches for Mary of Guise, the mother of Mary, Queen of Scots, who was betrothed to the Dauphin (afterwards Francis II).
From Scotland he passed into England in 1559, and treated with Queen Elizabeth respecting her claims on Calais, a settlement of which was effected at the congress of Le Cateau-Cambrésis. He was next sent as ambassador to the princes of Germany, for the purpose of prevailing upon them to withdraw their favor from the Protestants. This embassy was followed by missions to Margaret of Austria, governess of the Netherlands, to Savoy, and then to Rome, to ascertain the views of Pope Paul IV in regard to France. Paul having died just before his arrival, Castelnau used hi |
https://en.wikipedia.org/wiki/LF-space | In mathematics, an LF-space, also written (LF)-space, is a topological vector space (TVS) X that is a locally convex inductive limit of a countable inductive system of Fréchet spaces.
This means that X is a direct limit of a direct system in the category of locally convex topological vector spaces and each is a Fréchet space. The name LF stands for Limit of Fréchet spaces.
If each of the bonding maps is an embedding of TVSs then the LF-space is called a strict LF-space. This means that the subspace topology induced on by is identical to the original topology on .
Some authors (e.g. Schaefer) define the term "LF-space" to mean "strict LF-space," so when reading mathematical literature, it is recommended to always check how LF-space is defined.
Definition
Inductive/final/direct limit topology
Throughout, it is assumed that
is either the category of topological spaces or some subcategory of the category of topological vector spaces (TVSs);
If all objects in the category have an algebraic structure, then all morphisms are assumed to be homomorphisms for that algebraic structure.
is a non-empty directed set;
is a family of objects in where is a topological space for every index ;
To avoid potential confusion, should not be called 's "initial topology" since the term "initial topology" already has a well-known definition. The topology is called the original topology on or 's given topology.
is a set (and if objects in also have algebraic structures, then is automatically assumed to have has whatever algebraic structure is needed);
is a family of maps where for each index , the map has prototype . If all objects in the category have an algebraic structure, then these maps are also assumed to be homomorphisms for that algebraic structure.
If it exists, then the final topology on in , also called the colimit or inductive topology in , and denoted by or , is the finest topology on such that
is an object in , and
for every ind |
https://en.wikipedia.org/wiki/YaCy | YaCy (pronounced “ya see”) is a free distributed search engine, built on the principles of peer-to-peer (P2P) networks created by Michael Christen in 2003. The engine is written in Java and distributed on several hundred computers, , so-called YaCy-peers. Each YaCy-peer independently crawls through the Internet, analyzes and indexes found web pages, and stores indexing results in a common database (so-called index) which is shared with other YaCy-peers using principles of peer-to-peer. It is a search engine that everyone can use to build a search portal for their intranet and to help search the public internet clearly.
Compared to semi-distributed search engines, the YaCy-network has a distributed architecture. All YaCy-peers are equal and no central server exists. It can be run either in a crawling mode or as a local proxy server, indexing web pages visited by the person running YaCy on their computer. Several mechanisms are provided to protect the user's privacy. Access to the search functions is made by a locally run web server which provides a search box to enter search terms, and returns search results in a similar format to other popular search engines.
System components
YaCy search engine is based on four elements:
Crawler A search robot that traverses between web pages, analyzing their content.
Indexer It creates a reverse word index (RWI), i.e., each word from the RWI has its own list of relevant URLs and ranking information. Words are saved in the form of word hashes.
Search and administration interface Made as a web interface provided by a local HTTP servlet with servlet engine.
Data storage Used to store the reverse word index database utilizing a distributed hash table.
Search-engine technology
YaCy is a complete search appliance with user interface, index, administration and monitoring.
YaCy harvests web pages with a web crawler. Documents are then parsed, indexed and the search index is stored locally. If your peer is part of a peer network, t |
https://en.wikipedia.org/wiki/Digital%20sum%20in%20base%20b | The digital sum in base b of a set of natural numbers is calculated as follows: express each of the numbers in base b, then take the sum of corresponding digits and discard all carry overs. That is, the digital sum is the same as the normal sum except that no carrying is used.
For example, in decimal (base 10) arithmetic, the digital sum of 123 and 789 is 802:
3 + 9 = 12, discard the 10 leaving 2.
2 + 8 = 10, discard the 10 leaving 0.
1 + 7 = 8, there is no carry to discard.
123
789
---
802
More usually the digital sum is calculated in binary (base 2) where the result only depends upon whether there are an even or odd number of 1s in each column. This is the same function as parity or multiple exclusive ors.
For example:
011 (3)
100 (4)
101 (5)
---
010 (2) is the binary digital sum of 3, 4 and 5.
The binary digital sum is crucial for the theory of the game of Nim.
The digital sum in base b is an associative and commutative operation on the natural numbers; it has 0 as neutral element and every natural number has an inverse element under this operation. The natural numbers together with the base-b digital sum thus form an abelian group; this group is isomorphic to the direct sum of a countable number of copies of Z/bZ.
Integers |
https://en.wikipedia.org/wiki/De%20Sitter%20double%20star%20experiment | The de Sitter effect was described by Willem de Sitter in 1913 (as well as by Daniel Frost Comstock in 1910) and used to support the special theory of relativity against a competing 1908 emission theory by Walther Ritz that postulated a variable speed of light dependent on the velocity of the emitting object. De Sitter showed what Ritz's theory have predicted that the orbits of binary stars would appear more eccentric than consistent with experiment and with the laws of mechanics, however, the experimental result was negative. This was confirmed by Brecher in 1977 by observing the x-rays spectrum. For other experiments related to special relativity, see tests of special relativity.
The effect
According to simple emission theory, light thrown off by an object should move at a speed of with respect to the emitting object. If there are no complicating dragging effects, the light would then be expected to move at this same speed until it eventually reached an observer. For an object moving directly towards (or away from) the observer at , this light would then be expected to still be travelling at ( or ) at the time it reached us.
In 1913, Willem de Sitter argued that if this was true, a star orbiting in a double-star system would usually, with regard to us, alternate between moving towards us and away from us. Light emitted from different parts of the orbital path would travel towards us at different speeds. For a nearby star with a small orbital velocity (or whose orbital plane was almost perpendicular to our line of view) this might merely make the star's orbit seem erratic, but for a sufficient combination of orbital speed and distance (and inclination), the "fast" light given off during approach would be able to catch up with and even overtake "slow" light emitted earlier during a recessional part of the star's orbit, and the star would present an image that was scrambled and out of sequence. That is, Kepler's laws of motion would apparently be violated for |
https://en.wikipedia.org/wiki/Secure%20Digital%20Container | Secure Digital Container (SDC) is a compressed, encrypted executable file type that is made and used by the e-academy License Management System (ELMS) for secure downloads of primarily academic software. After being downloaded, it is decrypted and the software is extracted. The SDC file is created by e-academy for distribution of academic software purchased or freely downloaded by its academic user base. It cannot be opened without the Secure Delivery Client.
The Secure delivery client requests permission from ELMS to download. If ELMS denied the request, the download does not proceed. There is also a limited number of downloads a customer could use. When download count hits zero, a customer would be unable to download more copies of the software.
Older SDC files have weak protection and can be unpacked with the UnpackSDC 1.1 tool.
Recently related SDX files have been introduced. They are metadata for Secure Download Manager, which downloads either normal EXE/MSI files or encrypted SDC files and automatically decrypts them.
See also
DreamSpark
MSDNAA |
https://en.wikipedia.org/wiki/Combat%20information%20center | A combat information center (CIC) or action information centre (AIC) is a room in a warship or AWACS aircraft that functions as a tactical center and provides processed information for command and control of the near battlespace or area of operations. Within other military commands, rooms serving similar functions are known as command centers.
Regardless of the vessel or command locus, each CIC organizes and processes information into a form more convenient and usable by the commander in authority. Each CIC funnels communications and data received over multiple channels, which is then organized, evaluated, weighted and arranged to provide ordered timely information flow to the battle command staff under the control of the CIC officer and his deputies.
Overview
CICs are widely depicted in film and television treatments, frequently with large maps, numerous computer consoles and radar and sonar repeater displays or consoles, as well as the almost ubiquitous grease-pencil annotated polar plot on an edge-lighted transparent plotting board. At the time the CIC concept was born, the projected map-like polar display (PPI scopes) with the ship at the center was making its way into radar displays displacing the A-scope which was simply a time-delayed blip showing a range on the cathode ray tube display of an oscilloscope.
Such polar plots are used routinely in navigation and military action management to display time-stamped range and bearing information to the CIC decision makers. A single 'mark' (range and bearing datum) bears little actionable decision-making information by itself. A succession of such data tells much more, including whether the contact is closing or opening in range, an idea of its speed and direction (these are calculable, even from bearings-only data, given sufficient observations and knowledge of tactics), the relation to other contacts and their ranges and behaviors. Harvesting such data sets from the polar plots and computers (Common to sonar, ra |
https://en.wikipedia.org/wiki/Hosohedron | In spherical geometry, an -gonal hosohedron is a tessellation of lunes on a spherical surface, such that each lune shares the same two polar opposite vertices.
A regular -gonal hosohedron has Schläfli symbol with each spherical lune having internal angle radians ( degrees).
Hosohedra as regular polyhedra
For a regular polyhedron whose Schläfli symbol is {m, n}, the number of polygonal faces is :
The Platonic solids known to antiquity are the only integer solutions for m ≥ 3 and n ≥ 3. The restriction m ≥ 3 enforces that the polygonal faces must have at least three sides.
When considering polyhedra as a spherical tiling, this restriction may be relaxed, since digons (2-gons) can be represented as spherical lunes, having non-zero area.
Allowing m = 2 makes
and admits a new infinite class of regular polyhedra, which are the hosohedra. On a spherical surface, the polyhedron {2, n} is represented as n abutting lunes, with interior angles of . All these spherical lunes share two common vertices.
Kaleidoscopic symmetry
The digonal spherical lune faces of a -hosohedron, , represent the fundamental domains of dihedral symmetry in three dimensions: the cyclic symmetry , , , order . The reflection domains can be shown by alternately colored lunes as mirror images.
Bisecting each lune into two spherical triangles creates an -gonal bipyramid, which represents the dihedral symmetry , order .
Relationship with the Steinmetz solid
The tetragonal hosohedron is topologically equivalent to the bicylinder Steinmetz solid, the intersection of two cylinders at right-angles.
Derivative polyhedra
The dual of the n-gonal hosohedron {2, n} is the n-gonal dihedron, {n, 2}. The polyhedron {2,2} is self-dual, and is both a hosohedron and a dihedron.
A hosohedron may be modified in the same manner as the other polyhedra to produce a truncated variation. The truncated n-gonal hosohedron is the n-gonal prism.
Apeirogonal hosohedron
In the limit, the hosohedron becomes an ape |
https://en.wikipedia.org/wiki/Fluid%20solution | In general relativity, a fluid solution is an exact solution of the Einstein field equation in which the gravitational field is produced entirely by the mass, momentum, and stress density of a fluid.
In astrophysics, fluid solutions are often employed as stellar models. (It might help to think of a perfect gas as a special case of a perfect fluid.) In cosmology, fluid solutions are often used as cosmological models.
Mathematical definition
The stress–energy tensor of a relativistic fluid can be written in the form
Here
the world lines of the fluid elements are the integral curves of the velocity vector ,
the projection tensor projects other tensors onto hyperplane elements orthogonal to ,
the matter density is given by the scalar function ,
the pressure is given by the scalar function ,
the heat flux vector is given by ,
the viscous shear tensor is given by .
The heat flux vector and viscous shear tensor are transverse to the world lines, in the sense that
This means that they are effectively three-dimensional quantities, and since the viscous stress tensor is symmetric and traceless, they have respectively three and five linearly independent components. Together with the density and pressure, this makes a total of 10 linearly independent components, which is the number of linearly independent components in a four-dimensional symmetric rank two tensor.
Special cases
Several special cases of fluid solutions are noteworthy (here speed of light c = 1):
A perfect fluid has vanishing viscous shear and vanishing heat flux:
A dust is a pressureless perfect fluid:
A radiation fluid is a perfect fluid with :
The last two are often used as cosmological models for (respectively) matter-dominated and radiation-dominated epochs. Notice that while in general it requires ten functions to specify a fluid, a perfect fluid requires only two, and dusts and radiation fluids each require only one function. It is much easier to find such solutions than it is to find |
https://en.wikipedia.org/wiki/Haplogroup | A haplotype is a group of alleles in an organism that are inherited together from a single parent, and a haplogroup (haploid from the , haploûs, "onefold, simple" and ) is a group of similar haplotypes that share a common ancestor with a single-nucleotide polymorphism mutation. More specifically, a haplotype is a combination of alleles at different chromosomal regions that are closely linked and that tend to be inherited together. As a haplogroup consists of similar haplotypes, it is usually possible to predict a haplogroup from haplotypes. Haplogroups pertain to a single line of descent. As such, membership of a haplogroup, by any individual, relies on a relatively small proportion of the genetic material possessed by that individual.
Each haplogroup originates from, and remains part of, a preceding single haplogroup (or paragroup). As such, any related group of haplogroups may be precisely modelled as a nested hierarchy, in which each set (haplogroup) is also a subset of a single broader set (as opposed, that is, to biparental models, such as human family trees).
Haplogroups are normally identified by an initial letter of the alphabet, and refinements consist of additional number and letter combinations, such as (for example) . The alphabetical nomenclature was published in 2002 by the Y Chromosome Consortium.
In human genetics, the haplogroups most commonly studied are Y-chromosome (Y-DNA) haplogroups and mitochondrial DNA (mtDNA) haplogroups, each of which can be used to define genetic populations. Y-DNA is passed solely along the patrilineal line, from father to son, while mtDNA is passed down the matrilineal line, from mother to offspring of both sexes. Neither recombines, and thus Y-DNA and mtDNA change only by chance mutation at each generation with no intermixture between parents' genetic material.
Haplogroup formation
Mitochondria are small organelles that lie in the cytoplasm of eukaryotic cells, such as those of humans. Their primary function is to |
https://en.wikipedia.org/wiki/Iron%28II%29%20hydroxide | Iron(II) hydroxide or ferrous hydroxide is an inorganic compound with the formula Fe(OH)2. It is produced when iron(II) salts, from a compound such as iron(II) sulfate, are treated with hydroxide ions. Iron(II) hydroxide is a white solid, but even traces of oxygen impart a greenish tinge. The air-oxidised solid is sometimes known as "green rust".
Preparation and reactions
Iron(II) hydroxide is poorly soluble in water (1.43 × 10−3 g/L), or 1.59 × 10−5 mol/L. It precipitates from the reaction of iron(II) and hydroxide salts:
FeSO4 + 2 NaOH → Fe(OH)2 + Na2SO4
If the solution is not deoxygenated and iron not totally reduced in Fe(II), the precipitate can vary in colour starting from green to reddish brown depending on the iron(III) content. Iron(II) ions are easily substituted by iron(III) ions produced by its progressive oxidation.
It is also easily formed as a by-product of other reactions, a.o., in the synthesis of siderite, an iron carbonate (FeCO3), if the crystal growth conditions are imperfectly controlled.
Structure
Fe(OH)2 is a layer double hydroxide (LDH) easily accommodating in its crystal lattice ferric ions () produced by oxidation of ferrous ions () by the atmospheric oxygen ().
Related materials
Green rust is a recently discovered mineralogical form. All forms of green rust (including fougerite) are more complex and variable than the ideal iron(II) hydroxide compound.
Reactions
Under anaerobic conditions, the iron(II) hydroxide can be oxidised by the protons of water to form magnetite (iron(II,III) oxide) and molecular hydrogen.
This process is described by the Schikorr reaction:
3 Fe(OH)2 → Fe3O4 + H2 + 2 H2O
Anions such as selenite and selenate can be easily adsorbed on the positively charged surface of iron(II) hydroxide, where they are subsequently reduced by Fe2+. The resulting products are poorly soluble (Se0, FeSe, or FeSe2).
Natural occurrence
Iron dissolved in groundwater is in the reduced iron II form. If this groundwater comes in c |
https://en.wikipedia.org/wiki/CB%20Simulator | CompuServe CB Simulator was the first dedicated online chat service that was widely available to the public. It was developed by a CompuServe executive, Alexander "Sandy" Trevor, and released by CompuServe on February 21, 1980, as the first public, commercial multi-user chat program.
At that time, most people were familiar with citizens band radio, often abbreviated as CB radio, but multi-user chat and instant messaging were largely unknown. CompuServe CB used the CB radio paradigm to help users understand the new concept. Like CB radio, it had 40 "channels" and commands like "tune", "squelch", and "monitor". CompuServe CB quickly became the largest single product on CompuServe despite virtually no marketing. When 40 channels was not enough, additional "bands" were added, such as the "Adult" band.
The first online wedding occurred on CompuServe CB, and worldwide fans organized events to meet in the "real world" people they had met in CB. Compuserve's CBIG (CB Interest Group) Sysop Chris Dunn (ChrisDos) met his wife Pamela (Zebra3) there in the early 1980s, eventually being featured on the Phil Donahue Show. Later, enhancements to CompuServe CB were made to enable multiplayer games, digital pictures, multimedia, and large conferences. For example, Mick Jagger of the Rolling Stones held the first online multimedia conference using CompuServe CB from London on December 7, 1995.
One of the first online weddings occurred between *MilesTeg* and *Cinderella* on May 4, 1991. While the couple said their vows at the Silver Bells Wedding Chapel in Las Vegas, *TennesseeBunny* was dialed in with a laptop computer and a 2,400-bit-per-second modem and broadcast the event play by play. Later the couple celebrated at the "reception" during the Vegas CB Bash at the Palace Station Hotel. The wedding was attended by 20+ CB regulars in person and over 50 virtual guests online. The couple were still married as of 2019.
The CompuServe CB Simulator was also the setting for The Strange |
https://en.wikipedia.org/wiki/Synonymous%20substitution | A synonymous substitution (often called a silent substitution though they are not always silent) is the evolutionary substitution of one base for another in an exon of a gene coding for a protein, such that the produced amino acid sequence is not modified. This is possible because the genetic code is "degenerate", meaning that some amino acids are coded for by more than one three-base-pair codon; since some of the codons for a given amino acid differ by just one base pair from others coding for the same amino acid, a mutation that replaces the "normal" base by one of the alternatives will result in incorporation of the same amino acid into the growing polypeptide chain when the gene is translated. Synonymous substitutions and mutations affecting noncoding DNA are often considered silent mutations; however, it is not always the case that the mutation is silent.
Since there are 22 codes for 64 codons, roughly we should expect a random substitution to be synonymous with probability about 22/64 = 34%. The actual value is around 20%.
A synonymous mutation can affect transcription, splicing, mRNA transport, and translation, any of which could alter the resulting phenotype, rendering the synonymous mutation non-silent. The substrate specificity of the tRNA to the rare codon can affect the timing of translation, and in turn the co-translational folding of the protein. This is reflected in the codon usage bias that is observed in many species. A nonsynonymous substitution results in a change in amino acid that may be arbitrarily further classified as conservative (a change to an amino acid with similar physiochemical properties), semi-conservative (e.g. negatively to positively charged amino acid), or radical (vastly different amino acid).
Degeneracy of the genetic code
Protein translation involves a set of twenty amino acids. Each of these amino acids is coded for by a sequence of three DNA base pairs called a codon. Because there are 64 possible codons, but only 20-22 |
https://en.wikipedia.org/wiki/Polydextrose | Polydextrose is a synthetic polymer of glucose. It is a food ingredient classified as soluble fiber by the US FDA as well as Health Canada, . It is frequently used to increase the dietary fiber content of food, to replace sugar, and to reduce calories and fat content. It is a multi-purpose food ingredient synthesized from dextrose (glucose), plus about 10 percent sorbitol and 1 percent citric acid. Its E number is E1200. The FDA approved it in 1981.
It is 0.1 times as sweet as sugar.
History
Commercial manufacture of edible polydextrose originated with a process developed by Hans H. Rennhard of Pfizer, Inc. Rennhard began investigating the potential of polysaccharides as low-calorie replacements for sugar, fat, flour, and starch. In 1965, he created polydextrose, a polymer of dextrose, produced from the naturally occurring components: glucose, sorbitol, and citric acid.
Commercial uses
Polydextrose is commonly used as a replacement for sugar, starch, and fat in commercial beverages, cakes, candies, dessert mixes, breakfast cereals, gelatins, frozen desserts, puddings, and salad dressings. Polydextrose is frequently used as an ingredient in low-carb, sugar-free, and diabetic cooking recipes. It is also used as a humectant, stabiliser, and thickening agent.
Polydextrose is a form of soluble fiber and has shown healthful prebiotic benefits when tested in animals. It contains only 1 kcal per gram and, therefore, is able to help reduce calories.
However, polydextrose is not universally well tolerated. Doses as low as 10 g cause significantly more intestinal gas and flatulence than fermentation resistant psyllium. |
https://en.wikipedia.org/wiki/Ssh-agent | Secure Shell (SSH) is a protocol allowing secure remote login to a computer on a network using public-key cryptography. SSH client programs (such as ssh from OpenSSH) typically run for the duration of a remote login session and are configured to look for the user's private key in a file in the user's home directory (e.g., .ssh/id_rsa). For added security (for instance, against an attacker that can read any file on the local filesystem), it is common to store the private key in an encrypted form, where the encryption key is computed from a passphrase that the user has memorized. Because typing the passphrase can be tedious, many users would prefer to enter it just once per local login session. The most secure place to store the unencrypted key is in program memory, and in Unix-like operating systems, memory is normally associated with a process. A normal SSH client process cannot be used to store the unencrypted key because SSH client processes only last the duration of a remote login session. Therefore, users run a program called ssh-agent that runs beyond the duration of a local login session, stores unencrypted keys in memory, and communicates with SSH clients using a Unix domain socket.
Security issues
ssh-agent creates a socket and then checks the connections from ssh. Everyone who is able to connect to this socket also has access to the ssh-agent. The permissions are set as in a usual Linux or Unix system. When the agent starts, it creates a new directory in /tmp with restrictive permissions. The socket is located in this directory.
There is a procedure that may prevent malware from using the ssh-agent socket. If the ssh-add -c option is set when the keys are imported into the ssh-agent, then the agent requests a confirmation from the user using the program specified by the SSH_ASKPASS environment variable, whenever ssh tries to connect.
Ssh-agents can be "forwarded" onto a server you connect to, making their keys available there as well, for other con |
https://en.wikipedia.org/wiki/ClickOnce | ClickOnce is a component of Microsoft .NET Framework 2.0 and later, and supports deploying applications made with Windows Forms or Windows Presentation Foundation. It is similar to Java Web Start for the Java Platform or Zero Install for Linux.
Description
The core principle of ClickOnce is to ease the deployment of Windows applications. In addition, ClickOnce aims to solve three other problems with conventional deployment models: the difficulty in updating a deployed application, the impact of an application on the user's computer, and the need for administrator permissions to install applications.
ClickOnce-deployed applications are considered "low impact", in that they are installed per user, not per machine. Administrator privileges are not required to install these applications. Each ClickOnce application is isolated from the others. This means one ClickOnce application is not able to "break" another. ClickOnce employs Code Access Security (CAS) to prevent system functions being called by a ClickOnce application from the web, ensuring the security of data and the client system in general.
Applications
The ClickOnce model supports both installed applications (akin to conventional Windows applications with Start Menu integration) and online applications (browser-hosted applications that are not installed, only run and cached). ClickOnce applications can be deployed to a computer from an internet location, a network share, or a local file location such as a CD-ROM.
The ClickOnce deployment technology has been integrated into Visual Studio 2005 and later. It is also natively supported by MSBuild, Microsoft's build management technology.
Manifests
A ClickOnce deployment is controlled through the use of two XML manifest files: a deployment manifest and an application manifest. The manifests are in the same XML format as the side-by-side assembly implementation. The deployment manifest (*.application file) describes the deployment model: the current version, upda |
https://en.wikipedia.org/wiki/RRKM%20theory | The Rice–Ramsperger–Kassel–Marcus (RRKM) theory is a theory of chemical reactivity. It was developed by Rice and Ramsperger in 1927 and Kassel in 1928 (RRK theory) and generalized (into the RRKM theory) in 1952 by Marcus who took the transition state theory developed by Eyring in 1935 into account. These methods enable the computation of simple estimates of the unimolecular reaction rates from a few characteristics of the potential energy surface.
Assumption
Assume that the molecule consists of harmonic oscillators, which are connected and can exchange energy with each other.
Assume the possible excitation energy of the molecule to be , which enables the reaction to occur.
The rate of intra-molecular energy distribution is much faster than that of reaction itself.
As a corollary to the above, the potential energy surface does not have any "bottlenecks" for which certain vibrational modes may be trapped for longer than the average time of the reaction
Derivation
Assume that is an excited molecule:
where stands for product, and for the critical atomic configuration with the minimum energy along the reaction coordinate.
The unimolecular rate constant is obtained as follows:
where is the microcanonical transition state theory rate constant, is the sum of states for the active degrees of freedom in the transition state, is the quantum number of angular momentum, is the collision frequency between molecule and bath molecules, and are the molecular vibrational and external rotational partition functions.
See also
Transition state theory |
https://en.wikipedia.org/wiki/SNARE%20protein | SNARE proteins – "SNAP REceptors" – are a large protein family consisting of at least 24 members in yeasts, more than 60 members in mammalian cells, and some numbers in plants. The primary role of SNARE proteins is to mediate the fusion of vesicles with the target membrane; this notably mediates exocytosis, but can also mediate the fusion of vesicles with membrane-bound compartments (such as a lysosome). The best studied SNAREs are those that mediate the release of synaptic vesicles containing neurotransmitters in neurons. These neuronal SNAREs are the targets of the neurotoxins responsible for botulism and tetanus produced by certain bacteria.
Types
SNAREs can be divided into two categories: vesicle or v-SNAREs, which are incorporated into the membranes of transport vesicles during budding, and target or t-SNAREs, which are associated with nerve terminal membranes. Evidence suggests that t-SNAREs form stable subcomplexes which serve as guides for v-SNARE, incorporated into the membrane of a protein-coated vesicle, binding to complete the formation of the SNARE complex. Several SNARE proteins are located on both vesicles and target membranes, therefore, a more recent classification scheme takes into account structural features of SNAREs, dividing them into R-SNAREs and Q-SNAREs. Often, R-SNAREs act as v-SNAREs and Q-SNAREs act as t-SNAREs. R-SNAREs are proteins that contribute an arginine (R) residue in the formation of the zero ionic layer in the assembled core SNARE complex. One particular R-SNARE is synaptobrevin, which is located in the synaptic vesicles. Q-SNAREs are proteins that contribute a glutamine (Q) residue in the formation of the zero ionic layer in the assembled core SNARE complex. Q-SNAREs include syntaxin and SNAP-25. Q-SNAREs are further classified as Qa-, Qb-, or Qc-SNAREs depending on their location in the four-helix bundle.
Occurrence
Variants are known from yeasts, mammals Drosophila, and Caenorhabditis elegans.
Structure
SNAREs |
https://en.wikipedia.org/wiki/Classification%20of%20electromagnetic%20fields | In differential geometry and theoretical physics, the classification of electromagnetic fields is a pointwise classification of bivectors at each point of a Lorentzian manifold. It is used in the study of solutions of Maxwell's equations and has applications in Einstein's theory of relativity.
The classification theorem
The electromagnetic field at a point p (i.e. an event) of a Lorentzian spacetime is represented by a real bivector defined over the tangent space at p.
The tangent space at p is isometric as a real inner product space to E1,3. That is, it has the same notion of vector magnitude and angle as Minkowski spacetime. To simplify the notation, we will assume the spacetime is Minkowski spacetime. This tends to blur the distinction between the tangent space at p and the underlying manifold; fortunately, nothing is lost by this specialization, for reasons we discuss as the end of the article.
The classification theorem for electromagnetic fields characterizes the bivector F in relation to the Lorentzian metric by defining and examining the so-called "principal null directions". Let us explain this.
The bivector Fab yields a skew-symmetric linear operator defined by lowering one index with the metric. It acts on the tangent space at p by . We will use the symbol F to denote either the bivector or the operator, according to context.
We mention a dichotomy drawn from exterior algebra. A bivector that can be written as , where v, w are linearly independent, is called simple. Any nonzero bivector over a 4-dimensional vector space either is simple, or can be written as , where v, w, x, and y are linearly independent; the two cases are mutually exclusive. Stated like this, the dichotomy makes no reference to the metric η, only to exterior algebra. But it is easily seen that the associated skew-symmetric linear operator Fab has rank 2 in the former case and rank 4 in the latter case.
To state the classification theorem, we consider the eigenvalue problem fo |
https://en.wikipedia.org/wiki/Lego%20Trains | Lego Trains (stylized as LEGO Trains) is a product range and theme of the construction toy Lego, which incorporates buildable train sets. The Lego Trains theme became a sub-theme of Lego City in 2006. Products in the range have included locomotives, tracks, rolling stock, stations, signal boxes, and other track-side buildings and accessories. The theme is popular among adult fans, as well as children, and has spawned international associations and conventions. The train system is sometimes referred to as 'L-gauge' among Lego fans, in reference to traditional model railway scales. Lego trains use a nominal gauge of , based on 5-stud track centerlines gauge, corresponding with a circa 1:38 scale.
Development
The design of Lego trains has developed substantially, with several different systems introduced, with varying degrees of cross-compatibility.
The Blue Era (1966-1980)
Lego trains were first introduced in 1966 with Lego set number 080. The train sets used blue rails, and the first train sets were simply push-along. Set number 115 introduced 4.5 volt battery-operated trains (initially the battery box was handheld, but train sets soon contained a railcar that carried the battery box), and train sets numbered 720 (1969) and up operated on 12-volt electrified rails, introduced in 1969. In 1972, 4.5-volt trains gained a monolithic railcar that carried the batteries and contained both a bottom-mounted stop button to be actuated by signals, as well as a side-mounted lever for manual go/stop/back control and tripping by a track-side pivot. All three kinds (push trains, 4.5-volt battery-operated trains and 12-volt electric trains) existed alongside each other and even allowed for upgrades. The motors were the same size, the push trains used a motor-shaped dummy block of bricks, and all used the same wheel style. These wheels had the same press-fit metal axles as used in the two larger sizes of rubber-tire Lego wheels, which also meant that both 4.5-volt and 12-volt m |
https://en.wikipedia.org/wiki/Quantum%20fingerprinting | Quantum fingerprinting is a proposed technique that uses a quantum computer to generate a string with a similar function to the cryptographic hash function. Alice and Bob hold -bit strings and . Their goal and a referee's is to obtain the correct value of . To do this, quantum states are produced from the O(logn)-qubit state fingerprints and sent to the referee who performs the Swap test to detect if the fingerprints are similar or different with a high probability.
If unconditional guarantees of security are needed, and if it is impractical for the communicating parties to arrange to share a secret that can be used in a Carter–Wegman MAC, this technique might one day be faster than classical techniques given a quantum computer with 5 to 10 qubits. However, these circumstances are very unusual and it is unlikely the technique will ever have a practical application; it is largely of theoretical interest. |
https://en.wikipedia.org/wiki/Generality%20%28psychology%29 | In behavioral psychology, the assumption of generality is the assumption that the results of experiments involving schedules of reinforcement, conducted on non-human subjects (often pigeons), can be generalized to apply to humans. If the assumption holds, many aspects of daily human life can be understood in terms of these results. The naturalization of sunlight helps our bodies to stay awake and keep motivated. The darkness that comes with night tells our body to slow down for the day and get some rest. The ability to survive comes with generality. Experiments have been done to test inescapability and insolubility.
Fergus Lowe has questioned the generality of schedule effects in cases of fixed-interval performance among humans and non-humans.
The ability to generalize information from one situation to another is a function of several factors: the reliability of the original information; the paradigm's validity; one's understanding of the paradigm, the true determinants of the behavior, and the relevant details of the situations in question; and the similarity between the original source of the data and the situation to which it is to be applied.
There are both similarities and differences between the terms "stimulus generalization" and "generality of a functional relationship." Stimulus generalization is the description of the fact that an organism behaves in a similar way to similar stimuli, and that the more different the stimuli, the more different the behavior. The generality of a finding refers to the degree to which a functional relationship obtained in one situation is able to predict the obtained relationship in a new situation.
"Generality" refers more to functional relationships than individual events. That responses occur to X about the same as to Z is irrelevant; rather, that distributed practice helps in learning nonsense syllables and in learning other tasks. |
https://en.wikipedia.org/wiki/Winter%20Games | Winter Games is a sports video game developed by Epyx (and released in Europe by U.S. Gold), based on sports featured in the Winter Olympic Games.
A snow-and-ice themed follow-up to the highly successful Summer Games, Winter Games was released in 1985 for the Commodore 64 and later ported to several popular home computers and video game consoles of the 1980s.
The game was presented as a virtual multi-sport carnival called the "Epyx Winter Games" (there was no official IOC licensing in place) with up to 8 players each choosing a country to represent, and then taking turns competing in various events to try for a medal.
Events
The events available vary slightly depending on the platform, but include some or all of the following:
Slalom skiing
Ski jumping
Biathlon
Bobsled
Figure skating
Speed skating
Luge
Freestyle skiing; more precisely, the aerial skiing discipline, called "Hot Dog Aerials" in the game
Free skating
The game allows players to compete in all of the events sequentially, choose a few events, choose just one event, or practice an event.
Ports
Winter Games was ported to the Amiga, Apple II, Atari ST, Apple Macintosh, Apple IIGS, Amstrad CPC, ZX Spectrum, and IBM PC computer platforms, and to the Atari 2600, Atari 7800, Nintendo Entertainment System, and the Family Computer Disk System video game consoles. In 2004, it was featured as one of the games on the C64 Direct-to-TV. A Virtual Console version was released in Europe on February 20, 2009.
Reception
Winter Games was Epyx's best-selling Commodore game as of late 1987. Its sales had surpassed 250,000 copies by November 1989.
Info rated Winter Games four-plus stars out of five, stating that each event was good enough to be sold separately, and concluding that it was "sports simulation at its best!". In 1985, Zzap!64 gave 94% for the game calling it "another classic sport simulation from Epyx". Lemon64 website users have given average vote of 8.6 which places the game on top 20 list on the |
https://en.wikipedia.org/wiki/Rock%20cycle | The rock cycle is a basic concept in geology that describes transitions through geologic time among the three main rock types: sedimentary, metamorphic, and igneous. Each rock type is altered when it is forced out of its equilibrium conditions. For example, an igneous rock such as basalt may break down and dissolve when exposed to the atmosphere, or melt as it is subducted under a continent. Due to the driving forces of the rock cycle, plate tectonics and the water cycle, rocks do not remain in equilibrium and change as they encounter new environments. The rock cycle explains how the three rock types are related to each other, and how processes change from one type to another over time. This cyclical aspect makes rock change a geologic cycle and, on planets containing life, a biogeochemical cycle.
Transition to igneous rock
When rocks are pushed deep under the Earth's surface, they may melt into magma. If the conditions no longer exist for the magma to stay in its liquid state, it cools and solidifies into an igneous rock. A rock that cools within the Earth is called intrusive or plutonic and cools very slowly, producing a coarse-grained texture such as the rock granite. As a result of volcanic activity, magma (which is called lava when it reaches Earth's surface) may cool very rapidly on the Earth's surface exposed to the atmosphere and are called extrusive or volcanic rocks. These rocks are fine-grained and sometimes cool so rapidly that no crystals can form and result in a natural glass, such as obsidian, however the most common fine-grained rock would be known as basalt. Any of the three main types of rocks (igneous, sedimentary, and metamorphic rocks) can melt into magma and cool into igneous rocks.
Secondary changes
Epigenetic change (secondary processes occurring at low temperatures and low pressures) may be arranged under a number of headings, each of which is typical of a group of rocks or rock-forming minerals, though usually more than one of these alt |
https://en.wikipedia.org/wiki/AS2 | AS2 (Applicability Statement 2) is a specification on how to transport structured business-to-business data securely and reliably over the Internet. Security is achieved by using digital certificates and encryption.
Background
AS2 was created in 2002 by the IETF to replace AS1, which they created in the early 1990s.
The adoption of AS2 grew rapidly throughout the early 2000s because major players in the retail and fast-moving consumer goods industries championed AS2. Walmart was the first major retailer to require its suppliers to use the AS2 protocol instead of relying on dial-up modems for ordering goods. Amazon, Target, Lowe's, Bed, Bath, & Beyond and thousands of others followed suit. Many other industries use the AS2 protocol, including healthcare, as AS2 meets legal HIPAA requirements.
In some cases, AS2 is a way to bypass expensive value-added networks previously used for data interchange.
Technical overview
AS2 is specified in RFC 4130, and is based on HTTP and S/MIME. It was the second AS protocol developed and uses the same signing, encryption and MDN (as defined by RFC3798) conventions used in the original AS1 protocol introduced in the late 1990s by IETF . In other words:
Files are encoded as "attachments" in a standardized S/MIME message (an AS2 message). AS2 does not specify the contents of the files. Usually, the file contents are in a standardized format that is separately agreed upon, such as XML or EDIFACT.
AS2 messages are always sent using the HTTP or HTTPS protocol (Secure Sockets Layer — also known as SSL — is implied by HTTPS) and usually use the "POST" method (use of "GET" is rare).
Messages can be signed, but do not have to be.
Messages can be encrypted, but do not have to be.
Messages may request a Message Disposition Notification (MDN) back if all went well, but do not have to request such a message.
If the original AS2 message requested an MDN:
Upon the receipt of the message and its successful decryption or signature valida |
https://en.wikipedia.org/wiki/Sweet%20Tooth%20%28Twisted%20Metal%29 | Needles Kane—commonly known as Sweet Tooth—is a fictional character from the Twisted Metal video game series. Sweet Tooth is designed around the premise of a killer clown that drives a combat ice cream truck, and his face has been featured on the cover of every Twisted Metal game, making him the series' mascot. He is the only character besides Marcus Kane (who makes up his split personality) to drive more than one vehicle in any of the games, being the driver of "Dark Tooth", "Tower Tooth", and as of Twisted Metal: Lost, "Gold Tooth".
The character has gone through several redesigns differing from game to game, similar to fellow character Calypso, and his personality has grown progressively darker along the way. Despite the changes some factors remained uniform, notably the perpetual flame on his head introduced in the second game. Starting with Twisted Metal: Black, his design became a large, somewhat overweight bare chested clown with a mask featuring a maniacal smile. Twisted Metal: Head-On expanded on this idea, changing the mask to face paint and the smile to his own.
Design and history
Sweet Tooth's original look featured him as a green-haired, slim simple circus clown who had escaped from a mental institution. The design was expanded upon in the second game in response to changes to the truck's design, notably due to the clown head adorning the truck now featuring a personality of its own. The result gave Sweet Tooth the flaming head design seen on the character since. 989 Studios, who handled the next two games, put more emphasis on the clown design, redesigning his attire to that of a ringmaster in Twisted Metal 4; neither design was held in high regard by the developers, with David Jaffe stating his dislike of III's look. As of Black and beyond, the design was modified heavily, giving him increased bulk and other features that would be called his "classic look" by Incog Inc.'s design team.
The ice cream truck was actually designed well before the driver |
https://en.wikipedia.org/wiki/Lunar%20effect | The lunar effect is a purported correlation between specific stages of the roughly 29.5-day lunar cycle and behavior and physiological changes in living beings on Earth, including humans. A considerable number of studies have examined the effect on humans. By the late 1980s, there were at least 40 published studies on the purported lunar-lunacy connection, and at least 20 published studies on the purported lunar-birthrate connection. Literature reviews and metanalyses have found no correlation between the lunar cycle and human biology or behavior. In cases such as the approximately monthly cycle of menstruation in humans (but not other mammals), the coincidence in timing reflects no known lunar influence. The widespread and persistent beliefs about the influence of the Moon may depend on illusory correlation – the perception of an association that does not in fact exist.
In a number of marine animals, there is stronger evidence for the effects of lunar cycles. Observed effects relating to reproductive synchrony may depend on external cues relating to the presence or amount of moonlight. Corals contain light-sensitive cryptochromes, proteins that are sensitive to different levels of light. Coral species such as Dipsastraea speciosa tend to synchronize spawning in the evening or night, around the last quarter moon of the lunar cycle. In Dipsastraea speciosa, a period of darkness between sunset and moonrise appears to be a trigger for synchronized spawning. Another marine animal, the bristle worm Platynereis dumerilii, spawns a few days after a full moon. It contains a protein with light-absorbing flavin structures that differentially detect moonlight and sunlight. It is used as a model for studying the biological mechanisms of marine lunar cycles.
Contexts
Claims of a lunar connection have appeared in the following contexts:
Fertility
It is widely believed that the Moon has a relationship with fertility due to the corresponding human menstrual cycle, which |
https://en.wikipedia.org/wiki/Euler%20function | In mathematics, the Euler function is given by
Named after Leonhard Euler, it is a model example of a q-series and provides the prototypical example of a relation between combinatorics and complex analysis.
Properties
The coefficient in the formal power series expansion for gives the number of partitions of k. That is,
where is the partition function.
The Euler identity, also known as the Pentagonal number theorem, is
is a pentagonal number.
The Euler function is related to the Dedekind eta function as
The Euler function may be expressed as a q-Pochhammer symbol:
The logarithm of the Euler function is the sum of the logarithms in the product expression, each of which may be expanded about q = 0, yielding
which is a Lambert series with coefficients -1/n. The logarithm of the Euler function may therefore be expressed as
where -[1/1, 3/2, 4/3, 7/4, 6/5, 12/6, 8/7, 15/8, 13/9, 18/10, ...] (see OEIS A000203)
On account of the identity , where is the sum-of-divisors function, this may also be written as
.
Also if and , then
Special values
The next identities come from Ramanujan's Notebooks:
Using the Pentagonal number theorem, exchanging sum and integral, and then invoking complex-analytic methods, one derives |
https://en.wikipedia.org/wiki/Anosov%20diffeomorphism | In mathematics, more particularly in the fields of dynamical systems and geometric topology, an Anosov map on a manifold M is a certain type of mapping, from M to itself, with rather clearly marked local directions of "expansion" and "contraction". Anosov systems are a special case of Axiom A systems.
Anosov diffeomorphisms were introduced by Dmitri Victorovich Anosov, who proved that their behaviour was in an appropriate sense generic (when they exist at all).
Overview
Three closely related definitions must be distinguished:
If a differentiable map f on M has a hyperbolic structure on the tangent bundle, then it is called an Anosov map. Examples include the Bernoulli map, and Arnold's cat map.
If the map is a diffeomorphism, then it is called an Anosov diffeomorphism.
If a flow on a manifold splits the tangent bundle into three invariant subbundles, with one subbundle that is exponentially contracting, and one that is exponentially expanding, and a third, non-expanding, non-contracting one-dimensional sub-bundle (spanned by the flow direction), then the flow is called an Anosov flow.
A classical example of Anosov diffeomorphism is the Arnold's cat map.
Anosov proved that Anosov diffeomorphisms are structurally stable and form an open subset of mappings (flows) with the C1 topology.
Not every manifold admits an Anosov diffeomorphism; for example, there are no such diffeomorphisms on the sphere . The simplest examples of compact manifolds admitting them are the tori: they admit the so-called linear Anosov diffeomorphisms, which are isomorphisms having no eigenvalue of modulus 1. It was proved that any other Anosov diffeomorphism on a torus is topologically conjugate to one of this kind.
The problem of classifying manifolds that admit Anosov diffeomorphisms turned out to be very difficult, and still has no answer for dimension over 3. The only known examples are infranilmanifolds, and it is conjectured that they are the only ones.
A sufficient condition f |
https://en.wikipedia.org/wiki/Quantum%20Monte%20Carlo | Quantum Monte Carlo encompasses a large family of computational methods whose common aim is the study of complex quantum systems. One of the major goals of these approaches is to provide a reliable solution (or an accurate approximation) of the quantum many-body problem. The diverse flavors of quantum Monte Carlo approaches all share the common use of the Monte Carlo method to handle the multi-dimensional integrals that arise in the different formulations of the many-body problem.
Quantum Monte Carlo methods allow for a direct treatment and description of complex many-body effects encoded in the wave function, going beyond mean-field theory. In particular, there exist numerically exact and polynomially-scaling algorithms to exactly study static properties of boson systems without geometrical frustration. For fermions, there exist very good approximations to their static properties and numerically exact exponentially scaling quantum Monte Carlo algorithms, but none that are both.
Background
In principle, any physical system can be described by the many-body Schrödinger equation as long as the constituent particles are not moving "too" fast; that is, they are not moving at a speed comparable to that of light, and relativistic effects can be neglected. This is true for a wide range of electronic problems in condensed matter physics, in Bose–Einstein condensates and superfluids such as liquid helium. The ability to solve the Schrödinger equation for a given system allows prediction of its behavior, with important applications ranging from materials science to complex biological systems.
The difficulty is however that solving the Schrödinger equation requires the knowledge of the many-body wave function in the many-body Hilbert space, which typically has an exponentially large size in the number of particles. Its solution for a reasonably large number of particles is therefore typically impossible, even for modern parallel computing technology in a reasonable am |
https://en.wikipedia.org/wiki/Vesicle-associated%20membrane%20protein | Vesicle associated membrane proteins (VAMPs) are a family of SNARE proteins with similar structure, and are mostly involved in vesicle fusion.
VAMP1 and VAMP2 proteins known as synaptobrevins are expressed in brain and are constituents of the synaptic vesicles, where they participate in neurotransmitter release.
VAMP3 (known as cellubrevin) is ubiquitously expressed and participates in regulated and constitutive exocytosis as a constituent of secretory granules and secretory vesicles.
VAMP5 and VAMP7 participate in constitutive exocytosis.
VAMP5 is a constituent of secretory vesicles, myotubes and tubulovesicular structures.
VAMP7 is found both in secretory granules and endosomes.
VAMP8 (known as endobrevin) participates in endocytosis and is found in early endosomes. VAMP8 also participates the regulated exocytosis in pancreatic acinar cells.
VAMP4 is involved in transport from the Golgi. |
https://en.wikipedia.org/wiki/Synaptobrevin | Synaptobrevins (synaptobrevin isotypes 1-2) are small integral membrane proteins of secretory vesicles with molecular weight of 18 kilodalton (kDa) that are part of the vesicle-associated membrane protein (VAMP) family.
Synaptobrevin is one of the SNARE proteins involved in formation of the SNARE complexes.
Structure
Out of four α-helices of the core SNARE complex one is contributed by synaptobrevin, one by syntaxin, and two by SNAP-25 (in neurons).
Function
SNARE proteins are the key components of the molecular machinery that drives fusion of membranes in exocytosis. Their function however is subject to fine-tuning by various regulatory proteins collectively referred to as SNARE masters.
Classification
In the Q/R nomenclature for organizing SNARE proteins, VAMP/synaptobrevin family members are classified as R-SNAREs, so named for the presence of an arginine at a specific location within the primary sequence of the protein (as opposed to the SNAREs of the target membrane, which contain a glutamine and are so named Q-SNAREs). Synaptobrevin is classified as a V-SNARE in the V/T nomenclature, an alternative classification scheme in which SNAREs are classified as V-SNAREs and T-SNAREs for their localization to vesicles and target membranes, respectively.
Clinical significance
Synaptobrevin is degraded by tetanospasmin, a protein derived from the bacterium Clostridium tetani, which causes tetanus. A related bacterium, Clostridium botulinum, produces the botulinum toxin. Various botulinum toxin serotypes exist that each cleave specific peptide bonds of specific neuronal SNARE proteins, and synaptobrevin is this target protein for several of the serotypes.
Human proteins containing this domain
SEC22A; SEC22B; VAMP1; VAMP2; VAMP3; VAMP4; VAMP5; VAMP7; VAMP8; YKT6; |
https://en.wikipedia.org/wiki/Train%20noise | Train noise is vehicle noise made by trains. Noises may be heard inside the train and outside.
Subway systems, light rail transit and freight trains can send loud train noise into neighborhoods. Organizations such as the World Health Organization and the U.S. Environmental Protection Agency have set guidelines for noise level decibel limits for rapid transit. Noise levels can be reduced by installing noise barriers next to the track. Traditional clickety-clack sounds occur as a result of gaps in the rail to allow for thermal expansion. On most railways, the gaps are opposite each other and if the carriages are about the same length as the rails, an even clickety clack sound is generated. In the USA the rail joints are staggered, so not being opposite each other, a different and irregular sound is heard.
Sources
Several distinct sounds are created by various parts of the train, such as engines, traction motors, brakes, and the wheels rolling on the rails.
Roughness and irregularities on the wheel and rail surfaces are a source of noise and vibration. Rail joints and squats on the rail cause a familiar "clickety-clack" sound as train wheels roll over them. Rail corrugation (a periodic wear pattern resembling corrugated metal) causes tonal noise and vibration; fine, short-wavelength corrugation is known as "roaring rails" due to its high-pitched sound, whereas coarse, long-wavelength corrugation can cause the ground and nearby buildings to vibrate. Rail roughness and corrugation are treated by grinding the rails. This reduces noise in problem areas although trains make a distinctive tonal sound on freshly-ground track due to the pattern on the rail left by the grinding process, which wears flat over time.
Rail squeal is a sound caused by a train's wheels slipping under specific conditions, usually around sharp curves.
Air displacement of a train in a tunnel can create noise from turbulence.
Trains also use horns, whistles, bells, and other noise-making devices f |
https://en.wikipedia.org/wiki/PageStream | PageStream (originally Publishing Partner) is a desktop publishing software package by Grasshopper LLC (United States) currently available for a variety of operating systems including Windows, Linux, and macOS. The software was originally released under the name Publishing Partner for the Atari ST in 1986 by Soft-Logic Publishing Corporation.
Publishing Partner 1.5 was released for the Atari ST and Commodore Amiga platform in 1989. Version 1.8 followed in 1990 with an improved user interface and manual. Publishing Partner Professional 2.0, renamed to PageStream 2.0, was released for the Amiga in 1990 and Atari ST in 1991. This version added support for PostScript fonts and for the Amiga, AGFA Compugraphic Intellifont support.
PageStream 2.2 for Amiga and Atari ST was released in 1992 with support for the HotLinks Editions publish-subscribe system which was bundled with the PageLiner text editor and BME bitmap image editor.
PageStream 3.0 for Amiga was released in 1994. The application was entirely rewritten with a new user interface and many new features including colour separations, table of contents, index, nested chapters, Bézier curves, horizontal and vertical multi-page spreads, drop caps, hanging punctuation, Pantone colors, auto-kerning, auto-hyphenation, and ARexx scripting support.
In 1996 PageStream 3.1 and 3.2 were released for Amiga and a pre-release of PageStream was made available for Macintosh System 7. Various extensions were released for PageStream including TextFX (vector text warp), Borders (vector borders for rectangles), and Gary's Effects (image processing filters).
PageStream 3.3 was released for Amiga and Macintosh in 1997 with new fly-out tools for shapes, grids, and notes, as well as RTF export, a character panel, and improved chapter support. The Macintosh version included support for AppleScript.
PageStream 4.0 was released in 1999 with added support for Windows and Linux support was added in 2004. According to the official website, |
https://en.wikipedia.org/wiki/Link%20adaptation | Link adaptation, comprising adaptive coding and modulation (ACM) and others (such as Power Control), is a term used in wireless communications to denote the matching of the modulation, coding and other signal and protocol parameters to the conditions on the radio link (e.g. the pathloss, the interference due to signals coming from other transmitters, the sensitivity of the receiver, the available transmitter power margin, etc.). For example, WiMAX uses a rate adaptation algorithm that adapts the modulation and coding scheme (MCS) according to the quality of the radio channel, and thus the bit rate and robustness of data transmission. The process of link adaptation is a dynamic one and the signal and protocol parameters change as the radio link conditions change—for example in High-Speed Downlink Packet Access (HSDPA) in Universal Mobile Telecommunications System (UMTS) this can take place every 2 ms.
Adaptive modulation systems invariably require some channel state information at the transmitter. This could be acquired in time-division duplex systems by assuming the channel from the transmitter to the receiver is approximately the same as the channel from the receiver to the transmitter. Alternatively, the channel knowledge can also be directly measured at the receiver, and fed back to the transmitter. Adaptive modulation systems improve rate of transmission, and/or bit error rates, by exploiting the channel state information that is present at the transmitter. Especially over fading channels which model wireless propagation environments, adaptive modulation systems exhibit great performance enhancements compared to systems that do not exploit channel knowledge at the transmitter.
Example
In HSDPA link adaptation is performed by:
Choice of modulation type—the link can employ QPSK for noisy channels and 16QAM for clearer channels. The former is more robust and can tolerate higher levels of interference but has lower spectral efficiency, which means it may transmi |
https://en.wikipedia.org/wiki/Bronchoconstriction | Bronchoconstriction is the constriction of the airways in the lungs due to the tightening of surrounding smooth muscle, with consequent coughing, wheezing, and shortness of breath.
Causes
The condition has a number of causes, the most common being emphysema as well as asthma. Exer an otherwise asymptomatic individual.
Emphysema
With emphysema the shortness of breath due to effective bronchoconstriction from excessive very thick mucus blockage (it is so thick that great difficulty is encountered in expelling it resulting in near exhaustion at times) can bring on panic attacks unless the individual expects this and has effectively learned pursed lip breathing to more quickly transfer oxygen to the blood via the damaged alveoli resulting from the disease. The most common cause of emphysema is smoking and smoking cessation is mandatory if this incurable disease is to be treated. Prevention of bronchoconstriction by this pathway is vital for people with emphysema and there are several anticholinergic medications that in combination with mucous thinning agents such as Guaifenesin cause significant improvement in breathing.
Exercise-induced bronchoconstriction
More generally termed exercise-induced asthma, the preferred and more accurate term exercise-induced bronchoconstriction better reflects underlying pathophysiology. It is also preferred due to the former term giving the false impression that asthma is caused by exercise.
In a patient with EIB, exercise initially follows the normal patterns of bronchodilation. However, by three minutes, the constriction sets in, which peaks at around 10–15 minutes, and usually resolves itself by an hour. During an episode of this type of bronchoconstriction, the levels of inflammatory mediators, particularly leukotrienes, histamine, and interleukin, increase. TH2-type lymphocytes are activated, with an increase in T cells expressing CD25 (IL-2R), and B cells expressing CD 23, causing increased production of IgE. After exercise, |
https://en.wikipedia.org/wiki/Elastic%20recoil%20detection | Elastic recoil detection analysis (ERDA), also referred to as forward recoil scattering (or, contextually, spectrometry), is an ion beam analysis technique in materials science to obtain elemental concentration depth profiles in thin films. This technique is known by several different names. These names are listed below. In the technique of ERDA, an energetic ion beam is directed at a sample to be characterized and (as in Rutherford backscattering) there is an elastic nuclear interaction between the ions of beam and the atoms of the target sample. Such interactions are commonly of Coulomb nature. Depending on the kinetics of the ions, cross section area, and the loss of energy of the ions in the matter, ERDA helps determine the quantification of the elemental analysis. It also provides information about the depth profile of the sample.
The energy of incident energetic ions can vary from 2 MeV to 200 MeV, depending on the studied sample. The energy of the beam should be enough to kick out (“recoil”) the atoms of the sample. Thus, ERD usually employs appropriate source and detectors to detect recoiled atoms.
ERDA setup is large, expensive and difficult to operate. Therefore, although it is commercially available, it is relatively uncommon in materials characterization. The angle of incidence that an ion beam makes with the sample must also be taken into account for correct analysis of the sample. This is because, depending on this angle, the recoiled atoms will be collected.
ERDA has been used since the mid-1970s. It has similar theory to Rutherford backscattering spectrometry (RBS), but there are minor differences in the set-up of the experiment. In case of RBS, the detector is placed in the back of the sample whereas in ERDA, the detector is placed in the front.
Characteristics of ERDA
The main characteristics of ERDA are listed below.
A variety of elements can be analyzed simultaneously as long as the atomic number of recoiled ion is smaller than the atomic n |
https://en.wikipedia.org/wiki/Degrees%20of%20freedom%20%28mechanics%29 | In physics, the degrees of freedom (DOF) of a mechanical system is the number of independent parameters that define its configuration or state. It is important in the analysis of systems of bodies in mechanical engineering, structural engineering, aerospace engineering, robotics, and other fields.
The position of a single railcar (engine) moving along a track has one degree of freedom because the position of the car is defined by the distance along the track. A train of rigid cars connected by hinges to an engine still has only one degree of freedom because the positions of the cars behind the engine are constrained by the shape of the track.
An automobile with highly stiff suspension can be considered to be a rigid body traveling on a plane (a flat, two-dimensional space). This body has three independent degrees of freedom consisting of two components of translation and one angle of rotation. Skidding or drifting is a good example of an automobile's three independent degrees of freedom.
The position and orientation of a rigid body in space is defined by three components of translation and three components of rotation, which means that it has six degrees of freedom.
The exact constraint mechanical design method manages the degrees of freedom to neither underconstrain nor overconstrain a device.
Motions and dimensions
The position of an n-dimensional rigid body is defined by the rigid transformation, [T] = [A, d], where d is an n-dimensional translation and A is an n × n rotation matrix, which has n translational degrees of freedom and n(n − 1)/2 rotational degrees of freedom. The number of rotational degrees of freedom comes from the dimension of the rotation group SO(n).
A non-rigid or deformable body may be thought of as a collection of many minute particles (infinite number of DOFs), this is often approximated by a finite DOF system. When motion involving large displacements is the main objective of study (e.g. for analyzing the motion of satellites), |
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