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https://en.wikipedia.org/wiki/Jedediah%20Buxton | Jedediah Buxton (1707–1772) was a noted English mental calculator, born at Elmton, near Creswell, in Derbyshire.
Life
Buxton was born in 1707 and although his father was schoolmaster of Elmton, and his grandfather had been the vicar, he could not write; and his knowledge, except of numbers, was extremely limited. How he came to understand the relative proportions of numbers and their progressive denominations, he did not remember. However, this was his interest. He frequently took no notice of objects, and when he did, it was only with reference to their numbers. After hearing a sermon he knew nothing about its content other than that it contained a certain number of words which he had counted during its delivery.
He measured the lands of Elmton, consisting of some thousand acres (4 km2), simply by striding over it. He gave the area not only in acres, roods and perches, but even in square inches. After this, he reduced them into square hairs'-breadths, reckoning forty-eight to each side of the inch. His memory was so great, that in resolving a question he could leave off and resume the operation again at the same point after the lapse of several months. His perpetual application to figures prevented the acquisition of other knowledge. Among the examples of Buxton's arithmetical feats which are given are his calculation of the product of a farthing doubled 139 times. The result, expressed in pounds, extends to thirty-nine figures, and is correct so far as it can be readily verified by the use of logarithms. Buxton afterwards multiplied this enormous number by itself. It appears that he had invented an original nomenclature for large numbers, a 'tribe' being the cube of a million, and a 'cramp' (if Mr. Holliday's statement can be trusted) a thousand 'tribes of tribes'.
Journey to London
His mental acuity was tested in 1754 by the Royal Society when he walked to London, who acknowledged their satisfaction by presenting him with a handsome gratuity. During his visit |
https://en.wikipedia.org/wiki/Flip-Chip%20module | A Flip-Chip module is a component of digital logic systems made by the Digital Equipment Corporation (DEC) for its PDP-7, PDP-8, PDP-9, and PDP-10 computers, and related peripherals, beginning on August 24, 1964.
Description
As used by DEC, the term described a proprietary way to package electronic circuitry which was used for central processing units, peripheral controllers, and many other digital or analog electronic products produced by the company. The first flip-chip modules mated with single-sided 18-contact card edge connectors with contacts on 1/8 inch centers. Circuit boards were 2-7/16 inches wide by 5 inches long, with a handle adding 1/2 inch. Double-height modules with two connectors side by side were 5-3/16 inches wide. Later, when two-sided boards were introduced, upwards-compatible double-sided 36-contact edge connectors were used, but the basic connector and board dimensions remained unchanged. If more component real estate area were required for electronic circuitry, the "standard-length" modules would be supplemented by "extended-length" modules.
The company eventually produced extended-length quad-height (four connectors) and hex-height (six connectors) modules as larger circuit boards came into use; these larger boards often included metal levers to handle the larger forces need to insert or extract the boards from mating backplane connectors. The circuit boards (modules) were assembled into larger systems by plugging them into backplanes composed of blocks of connectors. These connectors were in turn interconnected by wirewrapping. (The earlier DEC System Modules used a hand-wired and soldered backplane. Manufacturing difficulties with this led DEC to investigate Gardner-Denver's automated wirewrap technology.) Troubleshooting would narrow down a fault to the module level, and a defective or suspected faulty module would be replaced by a known-good one, to repair a malfunctioning computer system.
The plastic handles were color-coded to |
https://en.wikipedia.org/wiki/ABX%20test | An ABX test is a method of comparing two choices of sensory stimuli to identify detectable differences between them. A subject is presented with two known samples (sample , the first reference, and sample , the second reference) followed by one unknown sample that is randomly selected from either A or B. The subject is then required to identify X as either A or B. If X cannot be identified reliably with a low p-value in a predetermined number of trials, then the null hypothesis cannot be rejected and it cannot be proven that there is a perceptible difference between A and B.
ABX tests can easily be performed as double-blind trials, eliminating any possible unconscious influence from the researcher or the test supervisor. Because samples A and B are provided just prior to sample X, the difference does not have to be discerned from assumption based on long-term memory or past experience. Thus, the ABX test answers whether or not, under the test circumstances, a perceptual difference can be found.
ABX tests are commonly used in evaluations of digital audio data compression methods; sample A is typically an uncompressed sample, and sample B is a compressed version of A. Audible compression artifacts that indicate a shortcoming in the compression algorithm can be identified with subsequent testing. ABX tests can also be used to compare the different degrees of fidelity loss between two different audio formats at a given bitrate.
ABX tests can be used to audition input, processing, and output components as well as cabling: virtually any audio product or prototype design.
History
The history of ABX testing and naming dates back to 1950 in a paper published by two Bell Labs researchers, W. A. Munson and Mark B. Gardner, titled Standardizing Auditory Tests.
The purpose of the present paper is to describe a test procedure which has shown promise in this direction and to give descriptions of equipment which have been found helpful in minimizing the variability of the te |
https://en.wikipedia.org/wiki/Light%20leak | A light leak is a hole or gap in the body of a camera, or other optical instrument, where light is able to "leak" into the normally light-tight chamber, exposing the film or sensor with extra light. This light is diffuse, although parts within the camera may cast shadows or reflect it in a particular way. For most purposes this is considered a problem. Within the lomography movement it is seen as a positive effect, giving photos character.
One frequent source of light leaks in 35 mm cameras is around the film door due to degrading foam. Replacing the foam is a simple matter. Medium format system cameras or large format cameras may have leaks between their various interchangeable parts or in old leather bellows. Electrical tape is often used to repair light leaks in these cases.
A light leak, considered as a problem, is a kind of stray light. It is possible to have a "virtual" light leak in spectral regions, like portions of the IR spectrum at room temperature, where surfaces inside the system emit significant amounts of radiation.
They can be created and emulated in digital photography and videography, either during production or after. In the first instance, the photographer or videographer removes the camera lens while photographing or recording and overloads the image sensor. This is usually used to create leaks which can then be overlaid onto another image or video. Or they can be created entirely digitally, with common photo-editing software packages such as Adobe Photoshop, and overlaid into the image. |
https://en.wikipedia.org/wiki/Beeturia | Beeturia is the passing of red or pink urine after eating beetroots or foods colored with beetroot extract or beetroot pigments. The color is caused by the excretion of betalain (betacyanin) pigments such as betanin. The coloring is highly variable between individuals and between different occasions, and can vary in intensity from invisible to strong. The pigment is sensitive to oxidative degradation under strongly acidic conditions. Therefore, the urine coloring depends on stomach acidity and dwell time as well as the presence of protecting substances such as oxalic acid. Beeturia is often associated with red or pink feces.
Cause
The red color seen in beeturia is caused by the presence of unmetabolized betalain pigments such as betanin in beetroot passed through the body. The pigments are absorbed in the colon. Betalains are oxidation-sensitive redox indicators that are decolorized by hydrochloric acid, ferric ions, and colonic bacteria preparations. The gut flora play a not-yet-evaluated role in the breakdown of the pigment.
Explanations
There is some relationship to iron deficiency.
There is no known relation to deficiencies in liver metabolism or removal from the body by the kidneys.
There is no known direct genetic influence, and no single gene variant, that differentiates excreters from non-excreters.
Factors affecting beeturia
The extent of excreted pigment depends on:
The pigment content of the meal, including:
The type of beetroot (for instance, the pigment concentration of the Detroit Rubidus variety is twice that of the Firechief variety)
The addition of concentrated beetroot extract as a food additive to certain processed foods
The storage conditions of the meal, including light, heat, and oxygen exposure, and repeated freeze-thaw cycles that all could degrade the pigments
Urine volume, affecting the dilution of the dye
The stomach acidity and dwell time
The presence of protecting substances such as oxalic acid in the meal and during intes |
https://en.wikipedia.org/wiki/Wiener%20deconvolution | In mathematics, Wiener deconvolution is an application of the Wiener filter to the noise problems inherent in deconvolution. It works in the frequency domain, attempting to minimize the impact of deconvolved noise at frequencies which have a poor signal-to-noise ratio.
The Wiener deconvolution method has widespread use in image deconvolution applications, as the frequency spectrum of most visual images is fairly well behaved and may be estimated easily.
Wiener deconvolution is named after Norbert Wiener.
Definition
Given a system:
where denotes convolution and:
is some original signal (unknown) at time .
is the known impulse response of a linear time-invariant system
is some unknown additive noise, independent of
is our observed signal
Our goal is to find some so that we can estimate as follows:
where is an estimate of that minimizes the mean square error
,
with denoting the expectation.
The Wiener deconvolution filter provides such a . The filter is most easily described in the frequency domain:
where:
and are the Fourier transforms of and ,
is the mean power spectral density of the original signal ,
is the mean power spectral density of the noise ,
, , and are the Fourier transforms of , and , and , respectively,
the superscript denotes complex conjugation.
The filtering operation may either be carried out in the time-domain, as above, or in the frequency domain:
and then performing an inverse Fourier transform on to obtain .
Note that in the case of images, the arguments and above become two-dimensional; however the result is the same.
Interpretation
The operation of the Wiener filter becomes apparent when the filter equation above is rewritten:
Here, is the inverse of the original system, is the signal-to-noise ratio, and is the ratio of the pure filtered signal to noise spectral density. When there is zero noise (i.e. infinite signal-to-noise), the term inside the square brackets equals 1, which means that the |
https://en.wikipedia.org/wiki/Raine%20syndrome | Raine syndrome (RNS), also called osteosclerotic bone dysplasia, is a rare autosomal recessive congenital disorder characterized by craniofacial anomalies including microcephaly, noticeably low set ears, osteosclerosis, a cleft palate, gum hyperplasia, a hypoplastic nose, and eye proptosis. It is considered to be a lethal disease, and usually leads to death within a few hours of birth. However, a recent report describes two studies in which children with Raine syndrome have lived to 8 and 11 years old, so it is currently proposed that there is a milder expression that the phenotype can take (Simpson 2009).
Signs and symptoms
Genetics
Raine syndrome appears to be an autosomal recessive disease. There are reports of recurrence in children born of the same parents, and an increased occurrence in children of closely related, genetically similar parents. Individuals with Raine syndrome were either homozygous or compound heterozygous for the mutation of FAM20C. Also observed have been nonsynonomous mutation and splice-site changes (Simpson et al. 2007).
FAM20C, located on chromosome 7p22.3, is an important molecule in bone development. Studies in mice have demonstrated its importance in the mineralization of bones in teeth in early development (OMIM, Simpson et al. 2007, Wang et al. 2010). FAM20C stands for “family with sequence similarity 20, member C.” It is also commonly referred to as DMP-4. It is a Golgi-enriched fraction casein kinase and an extracellular serine/threonine protein kinase. It is 107,743 bases long, with 10 exons and 584 amino acids (Weizmann Institute of Science).
Research
Current research describes Raine syndrome as a neonatal osteosclerotic bone dysplasia, indicated by its osteosclerotic symptoms that are seen in those with the disease. It has been found that a mutation in the gene FAM20C is the cause of the Raine syndrome phenotype. This microdeletion mutation leads to an unusual chromosome 7 arrangement. The milder phenotypes of Rai |
https://en.wikipedia.org/wiki/Disocactus%20%C3%97%20jenkinsonii | Disocactus × jenkinsonii is a hybrid between Disocactus phyllanthoides and Disocactus speciosus. It is perhaps the most commonly grown orchid cactus and seems to survive and flower under most conditions. It has a very complex taxonomic history and has been mistaken for Disocactus ackermannii for a long time.
History
In 1824, George Ackermann brought a part of a stem with him from Mexico and gave that to Tate who succeeded in flowering the specimen. Another specimen raised from Mexican seeds confirmed that this was really a novelty from Mexico and not a hybrid. The species was soon lost in cultivation. During the latter half of the 19th century, when cacti gave away to ferns, palms and orchids, only the toughest survived and as D. ackermannii is quite tricky it soon became lost in cultivation. About the same time some gardener succeeded in crossing D. phyllanthoides and D. speciosus producing a lovely red flowered hybrid. Being a vigorous, hardy, free-flowering plant, almost impossible to kill, it survived in collections. Unfortunately it was confused with the true D. ackermannii so when Britton and Rose published The Cactaceae, the switch had been made and the true species was forgotten. What Britton and Rose describe under Epiphyllum ackermanni is the hybrid, not the species. In 1943, Charles Gilles rediscovered the species in high, nearly unclimbable trees near Jalapa. He managed to collect living material and it was soon evident that the plant in cultivation was not the plant of Haworth. This hybrid is today correctly referred to as Disocactus × jenkinsonii 'Ackermannii'.
Description
The stems are flat to triangular, often quite thick and succulent. The flowers are more or less funnel shaped, usually orange to red. The stigma lobes are white, never lavender.
Cultivars
This cross has been remade many times creating several cultivars. However, many of them are confused today and cannot be identified. |
https://en.wikipedia.org/wiki/Common%20Vulnerability%20Scoring%20System | The Common Vulnerability Scoring System (CVSS) is a free and open industry standard for assessing the severity of computer system security vulnerabilities. CVSS attempts to assign severity scores to vulnerabilities, allowing responders to prioritize responses and resources according to threat. Scores are calculated based on a formula that depends on several metrics that approximate ease and impact of an exploit. Scores range from 0 to 10, with 10 being the most severe. While many utilize only the CVSS Base score for determining severity, temporal and environmental scores also exist, to factor in availability of mitigations and how widespread vulnerable systems are within an organization, respectively.
The current version of CVSS (CVSSv3.1) was released in June 2019.
History
Research by the National Infrastructure Advisory Council (NIAC) in 2003/2004 led to the launch of CVSS version 1 (CVSSv1) in February 2005, with the goal of being "designed to provide open and universally standard severity ratings of software vulnerabilities". This initial draft had not been subject to peer review or review by other organizations. In April 2005, NIAC selected the Forum of Incident Response and Security Teams (FIRST) to become the custodian of CVSS for future development.
Feedback from vendors utilizing CVSSv1 in production suggested there were "significant issues with the initial draft of CVSS". Work on CVSS version 2 (CVSSv2) began in April 2005 with the final specification being launched in June 2007.
Further feedback resulted in work beginning on CVSS version 3 in 2012, ending with CVSSv3.0 being released in June 2015.
Terminology
The CVSS assessment measures three areas of concern:
Base Metrics for qualities intrinsic to a vulnerability
Temporal Metrics for characteristics that evolve over the lifetime of vulnerability
Environmental Metrics for vulnerabilities that depend on a particular implementation or environment
A numerical score is generated for each of these metr |
https://en.wikipedia.org/wiki/Trabeculae%20of%20spleen | The fibroelastic coat of the spleen invests the organ, and at the hilum is reflected inward upon the vessels in the form of sheaths. From these sheaths, as well as from the inner surface of the fibroelastic coat, numerous small fibrous bands, the trabeculae of the spleen (or splenic trabeculae), emerge from all directions; these uniting, constitute the frame-work of the spleen.
The spleen therefore consists of a number of small spaces or areolae, formed by the trabeculae; in these areolae is contained the splenic pulp.
See also
Spleen
Trabecula |
https://en.wikipedia.org/wiki/International%20Radon%20Project | The International Radon Project (IRP) is a World Health Organization initiative to reduce the lung cancer risk around the world.
The IRP released their guidance to member countries in September 2009.
Exposure to radon in the home and workplace is one of the main risks of ionizing radiation causing tens of thousands of deaths from lung cancer each year globally. In order to reduce this burden it is important that national authorities have methods and tools based on solid scientific evidence and sound public health policy. The public needs to be aware of radon risks and the means to reduce and prevent these.
In 1996, WHO published a report containing several conclusions and recommendations covering the scientific understanding of radon risk and the need for countries to take action in the areas of risk management and risk communication.
Recent findings from case-control studies on lung cancer and exposure to radon in homes completed in many countries allow for substantial improvement in risk estimates and for further consolidation of knowledge by pooling data from these studies. The consistency of the findings from the latest pooled analyses of case-control studies from Europe and North America as well as China provides a strong argument for an international initiative to reduce indoor radon risks.
To fulfill these goals, WHO has developed a program on public health aspects of radon exposure. This project enjoys high priority with WHO's Department of Public Health and Environment. The key elements of the International Radon Project include:
Estimation of the global burden of disease (GBD) associated with exposure to radon, based on the establishment of a global radon database
Provision of guidance on methods for radon measurements and mitigation
Developing evidence-based public health guidance for Member States to formulate policy and advocacy strategy including the establishment of radon action levels
Development of approaches for radon risk communication.
|
https://en.wikipedia.org/wiki/CNet%20Technology | CNet Technology is a Taiwanese company that manufactures network equipment such as network cards, switches, and modems.
History
The company was established in 1989 in Hsinchu Science Park.
See also
List of companies of Taiwan |
https://en.wikipedia.org/wiki/Preclosure%20operator | In topology, a preclosure operator or Čech closure operator is a map between subsets of a set, similar to a topological closure operator, except that it is not required to be idempotent. That is, a preclosure operator obeys only three of the four Kuratowski closure axioms.
Definition
A preclosure operator on a set is a map
where is the power set of
The preclosure operator has to satisfy the following properties:
(Preservation of nullary unions);
(Extensivity);
(Preservation of binary unions).
The last axiom implies the following:
4. implies .
Topology
A set is closed (with respect to the preclosure) if . A set is open (with respect to the preclosure) if its complement is closed. The collection of all open sets generated by the preclosure operator is a topology; however, the above topology does not capture the notion of convergence associated to the operator, one should consider a pretopology, instead.
Examples
Premetrics
Given a premetric on , then
is a preclosure on
Sequential spaces
The sequential closure operator is a preclosure operator. Given a topology with respect to which the sequential closure operator is defined, the topological space is a sequential space if and only if the topology generated by is equal to that is, if
See also
Eduard Čech |
https://en.wikipedia.org/wiki/Yamaha%20M7CL | The Yamaha M7CL is a digital mixer that was manufactured by Yamaha Pro Audio. Two models with onboard analog input exist: the M7CL-32 and M7CL-48. These models have 40 (32 microphone and 4 stereo line)- and 56 (48 microphone and 4 stereo line)-input channels respectively, counting mono channels. Mixes, masters, groups, DCAs and individual channels can then be routed to an output via any number of the board's 16 configurable output XLR ports. The eight faders of the master control section can control multiple functions by way of "layers" in the same manner as the Yamaha PM5D. The board features Yamaha's "Selected Channel" technology, and Centralogic, unique to the M7CL. It can be augmented with more inputs or outputs via expansion cards, and can be fitted with third-party cards such as ones made by Aviom (A-Net), AuviTran (EtherSound), Audinate (Dante networking), AudioService (MADI), Dan Dugan (automixer), Riedel Communications (RockNet), Waves Audio (SoundGrid interface, DSP plugins), and Optocore (optical network). The M7CL-48ES recently joined the line-up with built-in EtherSound for digital networking using EtherSound stage boxes.
In 2006, the M7CL was recognized at the TEC Awards ceremony for best sound reinforcement console technology. In 2011, a wireless app to control the M7CL with an iPad was nominated but did not win the TEC Award for best wireless technology.
Features
Selected channel
The selected channel interface allows for quick and easy access to every parameter of any channel on the board quickly and easily. Selecting a channel will pull up all available parameters into the Centralogic section for adjustment.
Centralogic
Centralogic is a technology new and unique to the M7CL. It employs a touch screen, rotary encoders, and faders that dynamically map to whatever function or parameter is selected for adjustment. The control software has only 3 main screens, Overview, Selected Channel, and Effects Rack views. There are no additional layers to n |
https://en.wikipedia.org/wiki/Interlobular%20veins | The stellate veins join to form the interlobular veins, which pass inward between the rays, receive branches from the plexuses around the convoluted tubules, and, having arrived at the bases of the renal pyramids, join with the venae rectae. |
https://en.wikipedia.org/wiki/Interlobular%20arteries | Cortical radial arteries, formerly known as interlobular arteries, are renal blood vessels given off at right angles from the side of the arcuate arteries looking toward the cortical substance. The interlobular arteries pass directly outward between the medullary rays to reach the fibrous tunic, where they end in the capillary network of this part.
These vessels do not anastomose with each other, but form end-arteries.
In their outward course, they give off lateral branches, which are the afferent arterioles that supply the renal corpuscles. The afferent arterioles, then, enter Bowman's capsule and end in the glomerulus.
From each glomerulus, the corresponding efferent arteriole arises and then exits the capsule near the point where the afferent arteriole enters. Distally, efferent arterioles branch out to form dense plexuses (i.e., capillary beds) around their adjacent renal tubules. For cortical nephrons, a single network of capillaries, known as the peritubular capillaries, surrounds the entire renal tubule, whereas for juxtamedullary nephrons, the peritubular capillaries surround only the proximal and distal convoluted tubules, while another network branching from the efferent arteriole, known as the straight arterioles of kidney, surrounds the nephron loop (of Henle).
Name
Lote refers to them as "cortical radial arteries (formerly called inter-lobular arteries)"
Mescher et al refer to them as "interlobular arteries (or cortical radial arteries)" |
https://en.wikipedia.org/wiki/Stellate%20veins | The stellate veins are veins that lie beneath the fibrous tunic of the kidney. They are stellate in arrangement and are derived from the capillary network, into which the terminal branches of the interlobular arteries break up. These join to form the interlobular veins, which pass inward between the rays.
See also
renal circulation |
https://en.wikipedia.org/wiki/Renal%20lobe | The renal lobe is a portion of a kidney consisting of a renal pyramid and the renal cortex above it. In humans, on average there are 7 to 18 renal lobes.
It is visible without a microscope, though it is easier to see in humans than in other animals.
It is composed of many renal lobules, which are not visible without a microscope.
See also
Renal capsule
Renal medulla |
https://en.wikipedia.org/wiki/Cortical%20lobule | A cortical lobule (or renal lobule) is a part of a renal lobe. It consists of the nephrons grouped around a single medullary ray, and draining into a single collecting duct. Its near identical parallel is the rectal lobe, which is present in the majority of mammals. |
https://en.wikipedia.org/wiki/Jaws%20ratio | The jaws ratio is a measure used in finance to demonstrate the extent to which a trading entity's income growth rate exceeds its expenses growth rate, measured as a percentage. A larger positive value demonstrates that a trading entity is effectively generating more income over time than it is generating expenses, thereby potentially increasing its profitability, and profitability growth rate. The ratio may also be a negative percentage, which should be a cause for concern for the owners/management of a trading entity as this will over time result in eroded profitability. The ratio is so named because, when these rates are graphed, the space between the lines resembles a pair of jaws.
Strictly speaking, the jaws ratio is not a true ratio in that the calculation is not expressed as one number divided by another, and is calculated as follows:
. The jaws ratio is calculated by subtracting the expense growth rate from the income growth rate. |
https://en.wikipedia.org/wiki/Arcuate%20arteries%20of%20the%20kidney | The arcuate arteries of the kidney, also known as arciform arteries, are vessels of the renal circulation. They are located at the border of the renal cortex and renal medulla.
They are named after the fact that they are shaped in arcs due to the nature of the shape of the renal medulla.
Arcuate arteries arise from renal interlobar arteries. |
https://en.wikipedia.org/wiki/Arcuate%20vein | The arcuate vein is a vessel of the renal circulation. It is located at the border of the renal cortex and renal medulla. Arcuate veins pass around the renal pyramids at the border between the renal cortex and renal medulla in an arch shape. Arcuate veins receive blood from cortical radiate veins, and in turn deliver blood into the arcuate veins. |
https://en.wikipedia.org/wiki/Interlobar%20arteries | The interlobar arteries are vessels of the renal circulation which supply the renal lobes. The interlobar arteries branch from the lobar arteries which branch from the segmental arteries, from the renal artery. They give rise to arcuate arteries. |
https://en.wikipedia.org/wiki/Pancreatic%20bud | The ventral and dorsal pancreatic buds (or pancreatic diverticula) are outgrowths of the duodenum during human embryogenesis. They join to form the adult pancreas.
The proximal portion of the dorsal pancreatic bud gives rise to the accessory pancreatic duct, while the distal portion of the dorsal pancreatic bud and ventral pancreatic bud give rise to the major pancreatic duct.
The ventral pancreatic bud develops into the pancreatic head and uncinate process.
Associated Disorders
In pancreas divisum the ducts of the pancreas are not fused to form a full pancreas, but instead it remains as a distinct dorsal and ventral duct. Without the proper fusion of both ducts the majority of the pancreas drainage is mainly through the accessory papilla. Three different variations in pancreas divisum have been described: the first is the classic example of pancreas divisum in which the ventral duct is visualized but there is total failure of fusion; the second variation is with the absence of a ventral duct; and the third variation is when there is very basic communication between the two ducts. Pancreatitis is a major complication of pancreas divisum.
Additional images |
https://en.wikipedia.org/wiki/John%20Ernest | John Ernest (May 6, 1922 – July 21, 1994) was an American-born constructivist abstract artist. He was born in Philadelphia, in 1922. After living and working in Sweden and Paris from 1946 to 1951, he moved to London, England, where he lived and worked from 1951. As a mature student at Saint Martin's School of Art he came under the influence of Victor Pasmore and other proponents of constructivism. During the 1950s together with Anthony Hill, Kenneth Martin, Mary Martin, Stephen Gilbert and Gillian Wise he became a key member of the British constructivist (a.k.a. constructionist) art movement.
Ernest created both reliefs and free standing constructions. Several of his works are held at Tate Britain, including the Moebius Strip sculpture. He designed both a tower and a large wall relief at the International Union of Architects congress, South Bank, London, 1961. The exhibition structure also housed works by several of the other British constructivists.
Ernest had a lifelong fascination with mathematics that is reflected in his work, and together with constructivist artist Anthony Hill he made contributions to graph theory, studying crossing numbers of complete graphs.
Ernest was an atheist. |
https://en.wikipedia.org/wiki/Genetic%20Alliance | Genetic Alliance is a nonprofit organization, founded in 1986 by Joan O. Weiss, working with Victor A. McKusick, to advocate for health benefits in the accelerating field of genomic research. This organization is a network of over 1,000 disease advocacy organizations, universities, government organizations, private companies, and public policy organizations. They aim to advance genetic research agendas toward health benefit by engaging a broad range of stakeholders, including healthcare providers, researchers, industry professionals, public policy leaders, as well as individuals, families and communities. They create programs using a collaborative approach, and aim to increase efficiency and reduce obstacles in genetic research, while ensuring that voices from the involved disease communities are heard. They also promote public policies to advance healthcare. Genetic Alliance provides technical support and informational resources to guide disease-specific advocacy organizations in being their own research advocates. They also maintain a biobank as a central storage facility for several organizations who otherwise would not have the infrastructure to maintain their own repository.
History
The organization was founded in 1986 by Joan O. Weiss, working with Victor A. McKusick, to advocate for health benefits in the accelerating field of genomic research. The organisation is an umbrella organisation for a number of charities dealing with genetic diseases. The founding chair of the Genetic Alliance in 1989 was Ann Mercy Hunt who had founded the Tuberous Sclerosis Association.
Genetic Alliance Registry and Biobank
Genetic Alliance manages a biobank, the Genetic Alliance Registry and Biobank (GARB), which is a cooperatively-managed clinical data and tissue sample repository. GARB was established in 2003, and combines its standardized infrastructure with the interests and motivations of disease advocacy groups to develop effective diagnostic tools and treatments, to “ |
https://en.wikipedia.org/wiki/EyeTV | EyeTV is a European brand of TV tuners that allow users to watch TV on various devices including computers and smartphones. The brand was introduced in 2002 by Elgato Systems and was sold to Geniatech in 2016.
History
The first EyeTV hardware device was introduced in November 2002. It was a small USB-powered device that contained a cable tuner and hardware encoder in order to convert television video into an MPEG-1 format for watching on a computer. It also had coaxial and RCA plugs to connect it with a VCR or camcorder. A 2002 article in Macworld said it was the "first step" in bridging computers and television, but at this point still had "some kinks".
The next iteration was released in 2004 and called EyeTV 200. EyeTV 200 introduced a digital remote control and converted video programming into the higher-quality MPEG-2 format. A Macworld review gave it 4 out of 5 stars for "very good" and emphasized the video quality and ease-of-use. A story in The Washington Post said it was more expensive than some alternatives, but worked on a Mac and had good-quality recordings. Also in 2004 the first EyeTV product for satellite television was introduced with the EyeTV 310, which was later discontinued and replaced with EyeTV Sat.
That same year a home media server called EyeHome was introduced. It had recording features similar to other EyeTV products, but was also intended for streaming a computer display to a television. It connected Mac computers and televisions that share the same home network. A review in Macworld gave it three stars or a "good" rating, saying that it was easy to install and worked well with Apple applications, but some aspects were quirky or frustrating. Sound and Vision Magazine said it was "pretty darn cool" and an easy, inexpensive way to get media server functionality, though there were some user interface quirks. It gave the product an 89 out of 100 rating.
By 2005, several other EyeTV products had been introduced, such as the EyeTV for DTT |
https://en.wikipedia.org/wiki/Hybrid%20growth%20disorders | Hybrid growth disorders refer to reduced growth or overgrowth in an organism that is a hybrid of two different species. In some sense, it is a type of hybrid dysgenesis when the growth disorder proves deleterious, making it the opposite of heterosis or hybrid vigour.
Hybrid growth disorders may be referred to as a growth dysplasia, especially when resulting in overgrowth, although this terminology may be confusing since the term dysplasia is commonly used to imply an impending cancer. However, a hybrid growth disorder is not caused by cancer.
Hybrid growth disorders are exhibited among a variety organisms, including ligers, tigons, hybrid mice, and hybrid dwarf hamsters.
A study on hybrid mice which investigated the possible causes for hybrid growth disorders reveals genomic imprinting to have a major effect. Paternal imprinting may increase growth to maximize maternal resources allocated to his progeny, while maternal imprinting may suppress growth in favor of ensuring her own survival and equal allocation of resources between offspring. This suggests that the extent of a disorder depends on the combination of parental species and their respective sexes, as demonstrated by the Vrana study. The study concludes that hybrid growth disorders most commonly affect the heterozygous sex, as expected by Haldane's rule. This would also explain why hybrid growth disorders often appear to affect one sex more than the other.
Similarly, a study of hybrids between dwarf hamster species Phodopus campbelli and Phodopus sungorus suggests that gene imprinting causes abnormal interactions between growth-promoting and growth-repressing genes which regulate placental and embryonic growth.
See also
F1 hybrid |
https://en.wikipedia.org/wiki/Gravitational%20wave | Gravitational waves are waves of the intensity of gravity that are generated by the accelerated masses of binary stars and other motions of gravitating masses, and propagate as waves outward from their source at the speed of light. They were first proposed by Oliver Heaviside in 1893 and then later by Henri Poincaré in 1905 as the gravitational equivalent of electromagnetic waves.
Gravitational waves were later predicted in 1916 by Albert Einstein on the basis of his general theory of relativity as ripples in spacetime. Later he refused to accept gravitational waves. Gravitational waves transport energy as gravitational radiation, a form of radiant energy similar to electromagnetic radiation. Newton's law of universal gravitation, part of classical mechanics, does not provide for their existence, since that law is predicated on the assumption that physical interactions propagate instantaneously (at infinite speed)showing one of the ways the methods of Newtonian physics are unable to explain phenomena associated with relativity.
The first indirect evidence for the existence of gravitational waves came in 1974 from the observed orbital decay of the Hulse–Taylor binary pulsar, which matched the decay predicted by general relativity as energy is lost to gravitational radiation. In 1993, Russell A. Hulse and Joseph Hooton Taylor Jr. received the Nobel Prize in Physics for this discovery.
The first direct observation of gravitational waves was made in 2015, when a signal generated by the merger of two black holes was received by the LIGO gravitational wave detectors in Livingston, Louisiana, and in Hanford, Washington. The 2017 Nobel Prize in Physics was subsequently awarded to Rainer Weiss, Kip Thorne and Barry Barish for their role in the direct detection of gravitational waves.
In gravitational-wave astronomy, observations of gravitational waves are used to infer data about the sources of gravitational waves. Sources that can be studied this way include binary star |
https://en.wikipedia.org/wiki/List%20of%20live%20CDs | A live CD or live DVD is a CD-ROM or DVD-ROM containing a bootable computer operating system. Live CDs are unique in that they have the ability to run a complete, modern operating system on a computer lacking mutable secondary storage, such as a hard disk drive.
Rescue and repair
Billix – A multiboot distribution and system administration toolkit with the ability to install any of the included Linux distributions
Inquisitor – Linux kernel-based hardware diagnostics, stress testing and benchmarking live CD
Parted Magic – Entirely based on the 2.6 or newer Linux kernels
System Folder of classic Mac OS on a CD or on a floppy disk – Works on any media readable by 68k or PowerPC Macintosh computers
SystemRescueCD – A Linux kernel-based CD with tools for Windows and Linux repairs
BSD-based
FreeBSD based
DesktopBSD – as of 1.6RC1 FreeBSD and FreeSBIE based
FreeBSD – has supported use of a "fixit" CD for diagnostics since 1996
FreeNAS – m0n0wall-based
FreeSBIE (discontinued) – FreeBSD-based
GhostBSD – FreeBSD based with gnome GUI, installable to HDD
Ging – Debian GNU/kFreeBSD-based
m0n0wall (discontinued) – FreeBSD-based
TrueOS – FreeBSD-based
pfSense – m0n0wall-based
Other BSDs
DragonFly BSD
Linux kernel-based
Arch Linux based
Artix – LXQt preconfigured and OpenRC-oriented live CD and distribution
Archie – live CD version of Arch Linux.
Antergos
Chakra
Manjaro – primarily free software operating system for personal computers aimed at ease of use.
Parabola GNU/Linux-libre - distro endorsed by the Free Software Foundation
SystemRescueCD
Debian-based
These are directly based on Debian:
antiX – A light-weight edition based on Debian
Debian Live – Official live CD version of Debian
Devuan - A fork of the Debian Linux distribution that uses sysvinit, runit or OpenRC instead of systemd.
Finnix – A small system administration live CD, based on Debian testing, and available for x86 and PowerPC architectures
grml – Installable live CD for sysad |
https://en.wikipedia.org/wiki/Mathematical%20anxiety | Mathematical anxiety, also known as math phobia, is a feeling of tension and anxiety that interferes with the manipulation of numbers and the solving of mathematical problems in daily life and academic situations. This is, arguably, distinct from statistics anxiety where the negative state is the result of encountering statistics at any level but related to but distinct from mathematical anxiety.
Math Anxiety
Mark H. Ashcraft defines math anxiety as "a feeling of tension, apprehension, or fear that interferes with math performance" (2002, p. 1). It is a phenomenon that is often considered when examining students' problems in mathematics. According to the American Psychological Association, mathematical anxiety is often linked to testing anxiety. This anxiety can cause distress and likely causes a dislike and avoidance of all math-related tasks. The academic study of math anxiety originates as early as the 1950s, when Mary Fides Gough introduced the term mathemaphobia to describe the phobia-like feelings of many towards mathematics. The first math anxiety measurement scale was developed by Richardson and Suinn in 1972. Since this development, several researchers have examined math anxiety in empirical studies. Hembree (1990) conducted a meta-analysis of 151 studies concerning math anxiety. The study determined that math anxiety is related to poor math performance on math achievement tests and to negative attitudes concerning math. Hembree also suggests that math anxiety is directly connected with math avoidance.
Ashcraft (2002) suggests that highly anxious math students will avoid situations in which they have to perform mathematical tasks. Unfortunately, math avoidance results in less competency, exposure and math practice, leaving students more anxious and mathematically unprepared to achieve. In college and university, anxious math students take fewer math courses and tend to feel negative towards the subject. In fact, Ashcraft found that the correlation betwee |
https://en.wikipedia.org/wiki/Globally%20hyperbolic%20manifold | In mathematical physics, global hyperbolicity is a certain condition on the causal structure of a spacetime manifold (that is, a Lorentzian manifold). It is called hyperbolic in analogy with the linear theory of wave propagation, where the future state of a system is specified by initial conditions. (In turn, the leading symbol of the wave operator is that of a hyperboloid.) This is relevant to Albert Einstein's theory of general relativity, and potentially to other metric gravitational theories.
Definitions
There are several equivalent definitions of global hyperbolicity. Let M be a smooth connected Lorentzian manifold without boundary. We make the following preliminary definitions:
M is non-totally vicious if there is at least one point such that no closed timelike curve passes through it.
M is causal if it has no closed causal curves.
M is non-total imprisoning if no inextendible causal curve is contained in a compact set. This property implies causality.
M is strongly causal if for every point p and any neighborhood U of p there is a causally convex neighborhood V of p contained in U, where causal convexity means that any causal curve with endpoints in V is entirely contained in V. This property implies non-total imprisonment.
Given any point p in M, [resp. ] is the collection of points which can be reached by a future-directed [resp. past-directed] continuous causal curve starting from p.
Given a subset S of M, the domain of dependence of S is the set of all points p in M such that every inextendible causal curve through p intersects S.
A subset S of M is achronal if no timelike curve intersects S more than once.
A Cauchy surface for M is a closed achronal set whose domain of dependence is M.
The following conditions are equivalent:
The spacetime is causal, and for every pair of points p and q in M, the space of continuous future-directed causal curves from p to q is compact in the topology.
The spacetime has a Cauchy surface.
The spacetime i |
https://en.wikipedia.org/wiki/Relational%20Model/Tasmania | Relational Model/Tasmania (RM/T) was published by Edgar F. Codd in 1979 and is the name given to a number of extensions to his original relational model (RM) published in 1970. The overall goal of the RM/T was to define some fundamental semantic units, at "atomic" and "molecular" levels, for data modelling. Codd writes: "the result is a model with a richer variety of objects than the original relational model, additional insert-update-delete rules and some additional operators that make the algebra more powerful."
RM History
Between 1968 and 1988 Codd published over 30 papers on the relational model (RM) - the most famous of which is his 1970 paper. Up to 1978 the papers describe RM Version 1 (RM/V1). In early 1979 Codd first presented some new ideas, called RM/T ('T' for Tasmania), at an invited talk for the Australian Computer Science Conference in Hobart, Tasmania. Later that year the ACM journal published a paper on RM/T, in which Codd acknowledges the influence of Schmid & Swensen (1975) and Wiederhold (1977).
A later version of RM/T (we shall call it here "RM/D") was described by Chris Date in Date (1983) in which Date and Codd improved and refined RM/T, adding an entity type called designative. Although Codd writes nothing about this new type, Date offers a rationale in Date (1983, page 262). Date revised this 1983 article in Date (1995), which additionally compares the RM/T model with the E/R model.
Following a disappointing uptake of RM/T by the database industry, Codd decided to introduce the RM/T model more gradually. He planned to release a sequence of RM versions: RM/V2, RM/V3 etc. each time progressively including some of the ideas of the original RM/T into the new version. Perhaps this explains why there is no obvious mapping of concepts between RM/T and RM/V2. For example, there is no reference to associative or designative entity types in Codd's 1990 book that defines RM/V2. On the other hand, the book extends and builds on the existing body of |
https://en.wikipedia.org/wiki/Renal%20fascia | The renal fascia is a dense, elastic connective tissue envelope enclosing the kidney and adrenal gland, together with the layer of perirenal fat surrounding these two.
The renal fascia separates the adipose capsule of kidney from the overlying pararenal fat. The deeper layers deep to the renal fascia are, in order, the adipose capsule (or perirenal fat), the renal capsule and finally the parenchyma of the renal cortex. At the renal hilum, the renal capsule extends into the renal sinus.
The renal fascia was originally described as consisting of two distinct structures: the anterior renal fascia (Gerota's fascia), and posterior renal fascia (Zuckerkandl's fascia); these two fasciae were said to fuse laterally to form the lateroconal fascia. Understanding of the structure of the renal fascia has subsequently evolved.
Additional images |
https://en.wikipedia.org/wiki/Muscle%20hypertrophy | Muscle hypertrophy or muscle building involves a hypertrophy or increase in size of skeletal muscle through a growth in size of its component cells. Two factors contribute to hypertrophy: sarcoplasmic hypertrophy, which focuses more on increased muscle glycogen storage; and myofibrillar hypertrophy, which focuses more on increased myofibril size. It is the primary focus of bodybuilding-related activities.
Hypertrophy stimulation
A range of stimuli can increase the volume of muscle cells. These changes occur as an adaptive response that serves to increase the ability to generate force or resist fatigue in anaerobic conditions.
Strength training
Strength training (resistance training) causes neural and muscular adaptations which increase the capacity of an athlete to exert force through voluntary muscular contraction: After an initial period of neuro-muscular adaptation, the muscle tissue expands by creating sarcomeres (contractile elements) and increasing non-contractile elements like sarcoplasmic fluid.
Muscular hypertrophy can be induced by progressive overload (a strategy of progressively increasing resistance or repetitions over successive bouts of exercise to maintain a high level of effort). However, the precise mechanisms are not clearly understood; currently accepted hypotheses involve some combination of mechanical tension, metabolic fatigue, and muscular damage.
Muscular hypertrophy plays an important role in competitive bodybuilding and strength sports like powerlifting, American football, and Olympic weightlifting.
Anaerobic training
The best approach to specifically achieve muscle growth remains controversial (as opposed to focusing on gaining strength, power, or endurance); it was generally considered that consistent anaerobic strength training will produce hypertrophy over the long term, in addition to its effects on muscular strength and endurance. Muscular hypertrophy can be increased through strength training and other short-duration, high-i |
https://en.wikipedia.org/wiki/Sport%20auto%20%28Germany%29 | sport auto is a German automobile magazine, established in 1969, published monthly by Motor Presse Stuttgart, based in Stuttgart.
The magazine publishes its "Supertest" of cars, featuring the laptime at the Nordschleife. Until 2015 almost all supertest were done by Horst von Saurma, from 2015 laptimes are recorder by Christian Gebhardt. The magazine also runs a challenge for the fastest lap time driven with a car that is road legal (TÜV) and registered in Germany. The road legality rule also applies for the tires.
Racing participation
The journalists usually enter VLN and 24 Hours Nürburgring races, in cooperation with Honda or Aston Martin. Results are mixed, they caused at least two crashes.
Sport Auto Trophy
In 1995, the magazine introduced a Nordschleife lap record challenge for the fastest lap time driven with a car that is road legal, having passed German TÜV and is registered in Germany. The road legality rule also applies for the tires. After the trophy had been given to Blitz, a Japanese tuning parts company in 1997, sport auto editor Horst v. Saurma regained the record in 1999. After the sport auto record was lowered to 7:14 in 2005, sport auto announced to introduce rules according to their Hockenheimring-based Tuner GP event. In 2005, sport auto also clocked a 6:55 for a UK-registered Radical SR8 which is not eligible to sport autos ranking.
5 Supersportler auf der Nordschleife
In 2008, five super sports cars owned by an enthusiast were compared by Porsche factory driver Marc Basseng, winner of several VLN races in Porsche GT3 RSR. Timing was provided by sport auto as in a Supertest. The results were also reported elsewhere.
Supertest Nordschleife
During the industry testing sessions in which sport auto records its "Supertest", the track can not be traveled at full speed past "Tribüne 13" (T13, grandstand 13) in order to allow safe access from the old exit/entrance there. The missing uphill section, from a slow right hand corner, would take in |
https://en.wikipedia.org/wiki/Descending%20limb%20of%20loop%20of%20Henle | Within the nephron of the kidney, the descending limb of loop of Henle is the portion of the renal tubule constituting the first part of the loop of Henle.
Physiology
The permeability is as follows:
Also, the medullary interstitium is highly concentrated (because of the activity of the ascending limb), leading to a strong osmotic gradient from the descending limb to the medulla.
Because of these factors, the concentration of the urine increases dramatically in the descending limb. Osmolality can reach up to 1400 mOsmol/kg by the end of the descending limb.
Histology
The epithelium of the Thick segment is low simple cuboidal epithelium. The epithelium of the Thin segment is simple squamous.
They can be distinguished from the vasa recta by the absence of blood, and they can be distinguished from the thick ascending limb by the thickness of the epithelium.
Nomenclature
Like the ascending limb, the descending limb has thick and thin portions. However, this distinction is not as important physiologically as in the ascending limb, so often the two are treated as one structure. The thick descending limb is less important than the thin descending limb, so often the terms "descending limb" and "thin descending limb" are used interchangeably.
Some sources simply refer to a "thin limb". In this context, the thin ascending limb of loop of Henle would be included.
Additional images |
https://en.wikipedia.org/wiki/Ascending%20limb%20of%20loop%20of%20Henle | Within the nephron of the kidney, the ascending limb of the loop of Henle is a segment of the heterogenous loop of Henle downstream of the descending limb, after the sharp bend of the loop. This part of the renal tubule is divided into a thin and thick ascending limb; the thick portion is also known as the distal straight tubule, in contrast with the distal convoluted tubule downstream.
Structure
The ascending limb of the loop of Henle is a direct continuation from the descending limb of loop of Henle, and one of the structures in the nephron of the kidney. The ascending limb has a thin and a thick segment. The ascending limb drains urine into the distal convoluted tubule.
The thick ascending limb is found in the medulla of the kidney, and the thick ascending limb can be divided into a part that is in the renal medulla and a part that is in the renal cortex. The ascending limb is much thicker than the descending limb.
At the junction of the thick ascending limb and the distal convoluted tubule are a subset of 15–25 cells known as the macula densa that are part of renal autoregulation through the mechanism of tubuloglomerular feedback.
Histology
As in the descending limb, the epithelium is simple squamous epithelium.
Function
Thin ascending limb
The thin ascending limb is impermeable to water; but is permeable to ions allowing for some sodium reabsorption. Na/K-ATPase is expressed at very low levels in this segment and thus this reabsorption is likely through passive diffusion. Salt moves out of the tubule and into the interstitium due to osmotic pressure created by the countercurrent system.
Thick ascending limb
Functionally, the parts of the ascending limb in the medulla and cortex are very similar.
The medullary ascending limb is largely impermeable to water. Sodium (Na+), potassium (K+) and chloride (Cl−) ions are reabsorbed by active transport. The predominant mechanism of active transport in this segment is through the Na+/K+/Cl− co-transporter NKCC2 |
https://en.wikipedia.org/wiki/NP-40 | NP-40 (also known as Tergitol-type NP-40 and nonyl phenoxypolyethoxylethanol) is a commercially available detergent with CAS Registry Number 9016-45-9. NP-40 is an ethoxylated nonylphenol for non-ionic surfactants and can act as emulsifier and demulsifier agent.
NP-40 is often used to break open all membranes within a cell, including the nuclear membrane . To break only the cytoplasmic membrane, other detergents such as digitonin can be used.
NP-40 has applications in paper and textile processing, in paints and coatings, and in agrochemical manufacturing.
Care should be taken to avoid confusing NP-40 with Nonidet P-40 (octyl phenoxypolyethoxylethanol) which is currently out of production. Nonidet P-40 ("Non-Ionic Detergent") was originally manufactured and trademarked by the Shell Chemical Company, but was phased out of production in the early 2000s. Confusingly, biochemical protocols published between the 1960s and 2000s refer to Shell's Nonidet P-40 as NP-40. Shell's original Nonidet P-40 had a hydrophilic-lipophilic balance (HLB) value of 13.5, as opposed to 12.9 for the currently available IGEPAL CA-630, indicating that the currently available compound is more potent than the compound used in older publications. Indeed, according to a 2017 report, an additional dilution factor of 10 was required for the currently available NP-40 ("Nonidet P-40 substitutes") to match the activity of the previously available, and now discontinued, Shell's Nonidet P-40.
See also
Nonoxynol-9
Surfactant
Lipid bilayer
Detergent
Triton X-100 (differs only in the # of carbons in the aliphatic portion) |
https://en.wikipedia.org/wiki/Cohn%20process | The Cohn process, developed by Edwin J. Cohn, is a series of purification steps with the purpose of extracting albumin from blood plasma. The process is based on the differential solubility of albumin and other plasma proteins based on pH, ethanol concentration, temperature, ionic strength, and protein concentration. Albumin has the highest solubility and lowest isoelectric point of all the major plasma proteins. This makes it the final product to be precipitated, or separated from its solution in a solid form. Albumin was an excellent substitute for human plasma in World War Two. When administered to wounded soldiers or other patients with blood loss, it helped expand the volume of blood and led to speedier recovery. Cohn's method was gentle enough that isolated albumin protein retained its biological activity.
Process details
During the operations, the ethanol concentration change from zero initially to 40%. The pH decreases from neutral at 7 to more acidic at 4.8 over the course of the fractionation. The temperature starts at room temperature and decreases to −5 degrees Celsius. Initially, the blood is frozen. There are five major fractions. Each fraction ends with a specific precipitate. These precipitates are the separate fractions.
Fractions I, II, and III are precipitated out at earlier stages. The conditions of the earlier stages are 8% ethanol, pH 7.2, −3 °C, and 5.1% protein for Fraction I; 25% ethanol, pH of 6.9, −5 °C, and 3% protein. The albumin remains in the supernatant fraction during the solid/liquid separation under these conditions. Fraction IV has several unwanted proteins that need to be removed. In order to do this, the conditions are varied in order to precipitate the proteins out. The conditions to precipitate these proteins are raising the ethanol concentration from 18 to 40% and raising the pH from 5.2 to 5.8. Finally, albumin is located in fraction V. The precipitation of albumin is done by reducing the pH to 4.8, which is near the pI o |
https://en.wikipedia.org/wiki/B5000%20instruction%20set | The Burroughs B5000 was the first stack machine and also the first computer with a segmented virtual memory.
The Burroughs B5000 instruction set includes the set of valid operations for the B5000, B5500 and B5700. It is not compatible with the B6500, B7500, B8500 or their successors.
Instruction streams on a B5000 contain 12-bit syllables, four to a word. The architecture has two modes, Word Mode and Character Mode, and each has a separate repertoire of syllables. A processor may be either Control State or Normal State, and certain syllables are only permissible in Control State. The architecture does not provide for addressing registers or storage directly; all references are through the 1024 word Program Reference Table (PRT), current code segment, marked locations within the stack or to the A and B registers holding the top two locations on the stack. Burroughs numbers bits in a syllable from 0 (high bit) to 11 (low bit) and in a word from 0 (high bit) to 47 (low bit).
Word Mode
In Word Mode, there are four types of syllables.
The interpretation of the 10-bit relative address in Operand Call and Descriptor Call depends on the setting of several processor flags. For main programs (SALF off) it is always an offset into the Program Reference Table (PRT).
Character Mode |
https://en.wikipedia.org/wiki/Dioxathion | Dioxathion, systematically known as p-dioxane-2,3-diyl ethyl phosphorodithioate, is an organophosphate pesticide. It is used as an insecticide on livestock and as an acaricide on citrus fruits, deciduous fruits and nuts.
Uses
Under the trade name Delnav, it can be used to control insects and mites on apples, pears, quince, grapes, and walnuts, and finds use in the control of ticks, horn flies, lice and sheep keds in various livestock, either as a spray or as a dip. Under the trade name Deltic, it is a restricted use pesticide for exterior control of fleas, ticks and mites, in kennels, dog houses, yards, and other recreational areas.
Toxicity
Dioxathion is an Extremely Hazardous Substance, as defined by Section 302 of the U.S. Emergency Planning and Community Right-to-Know Act, and is no longer allowed to be sold in the United States. However, it continues to see use in some other countries. It has been known to cause inhibition of the enzyme cholinesterase in rats, and it is recommended that people who have exposure to dioxathion regularly get their plasma and red blood cell cholinesterase levels assessed. Persons exposed to other chemicals which affect cholinesterase levels, e.g. other organophosphates or carbamates, may be at an increased risk. There are no known carcinogenic or reproductive effects, but long term exposure may result in nerve damage, poor motor coordination, and personality changes of anxiety, depression or irritability.
Short-term effects may include irritation to the eyes, pupil constriction and blurring of vision, abdominal cramps, laboured breathing, nausea, vomiting, diarrhoea, muscle cramps and excess salivation. These are mostly classic symptoms of organophosphate poisoning.
Dioxathion must be stored away from alkalis, iron, tin and strong acids. Contact can be avoided by using protective clothing and eyeware. If poisoning occurs, a physician may administer atropine sulfate, or pralidoxime in case of severe poisoning. |
https://en.wikipedia.org/wiki/COSIC | The Computer Security and Industrial Cryptography research group, commonly called COSIC, is a research group at the Department of Electrical Engineering of KU Leuven, which is headed by Bart Preneel.
Research
Research and expertise in digital security:
Security architectures for information and communication systems
Cryptographic algorithms and protocols
Symmetric key
Public key
Post-quantum
Security for embedded systems
Privacy-preserving systems
Applications:
Cloud
Automotive
Privacy
Data Protection
Trusted Systems
E-payments
E-documents
...
AES
One of the well-known successes is the selection of Rijndael as the Advanced Encryption Standard (AES). Currently AES is used by millions of users in more than thousand products, such as the protection of US government information.
Research projects
COSIC has participated in over 50 European research projects.
IMEC
COSIC is part of the Smart Applications and Innovation Services of imec. |
https://en.wikipedia.org/wiki/Samara%20flag | The Samara Flag (, Samarsko zname, , Samarskoye znamya) is a historical military symbol of the Bulgarian Army.
History
The flag was woven by local nuns and given to the Bulgarian volunteers during the Russo-Turkish War of 1877–78 by inhabitants of the Russian city of Samara, on 18 May 1877.
The flag became famous after it escaped capture by Ottoman forces at the Battle of Stara Zagora, where many Bulgarian soldiers died in order to prevent the flag from being captured by the Ottoman forces.
The flag, originally intended for the rebels of the April Uprising, was handed to the Bulgarians near Ploieşti on 18 May, having been transported through Chişinău, where it arrived on 1 May. A delegation from the city of Samara, headed by Efim Kozhevnikov and Pyotr Alabin, handed the Samara flag to the volunteers in a special ceremony, with the flag being attached to its pole with gold nails. Tseko Petkov, a leader of a band in the Troyan part of the Balkan Mountains, exclaimed:
The flag, entrusted to the 3rd battalion of the Bulgarian volunteer corps, went through of the battles at Stara Zagora and Nova Zagora, where a number of flag-bearers perished protecting it (including Lieutenant-Colonel Pavel Kalitin), as well as the Battles of Shipka Pass and Sheynovo.
The Samara flag was initially kept in Radomir, the birthplace of its last bearer, Pavel Korchev. It was later kept in the royal palace in Sofia (now the National Art Gallery) from 1881. In 1946, the flag was transferred to the National Museum of Military History (NMMH). It has remained there ever since, preserved in a chamber under special conditions.
Two copies of the flag were made in 1958, one of which was sent to the Central Military Museum in Russia. Another two were subsequently created, one of which was made in the Mihail Maletski NMMH restoration workshop by in 1978. The nuns of the Russian-founded Knyazhevo Nunnery of the Shroud of the Most Holy Mother of God created another precise replica in 2006.
Desig |
https://en.wikipedia.org/wiki/Newton%E2%80%93Wigner%20localization | Newton–Wigner localization (named after Theodore Duddell Newton and Eugene Wigner) is a scheme for obtaining a position operator for massive relativistic quantum particles. It is known to largely conflict with the Reeh–Schlieder theorem outside of a very limited scope.
The Newton–Wigner position operators 1, 2, 3, are the premier notion of position
in relativistic quantum mechanics of a single particle. They enjoy the same
commutation relations with the 3 space momentum operators and transform under
rotations in the same way as the , , in ordinary QM. Though formally they have the same properties with respect to 1,
2, 3, as
the position in ordinary QM, they have additional properties: One of these is that
This ensures that the free particle moves at the expected velocity with the given momentum/energy.
Apparently these notions were discovered when attempting to define a self adjoint operator in the relativistic setting that resembled the
position operator in basic quantum mechanics in the sense that at low momenta it
approximately agreed with that operator. It also has several famous strange behaviors (see the Hegerfeldt theorem in particular), one of
which is seen as the motivation for having to introduce quantum field theory. |
https://en.wikipedia.org/wiki/ORVYL%20and%20WYLBUR | ORVYL is a time-sharing monitor developed by Stanford University for IBM System/360 and System/370 computers in 1967–68. ORVYL was one of the first time-sharing systems to be made available for IBM computers. Wylbur is a text editor and word processor program designed to work either without ORVYL, or in conjunction with ORVYL.
Overview
The names ORVYL and WYLBUR are often used interchangeably, but:
ORVYL is a timesharing monitor that supports a file system, command language, program execution and debugging, and provides supervisor services. The first version runs only on a 360/67, but later versions run on a System/370.
WYLBUR is a text editor, word processor, job submission and retrieval, and e-mail program designed to work in conjunction with ORVYL or with IBM's OS/360, SVS, and MVS operating systems.
MILTEN is terminal control software used by both ORVYL and WYLBUR for start/stop terminals.
WYLBUR is not a full standalone operating system in the mold of Dartmouth Time Sharing System (DTSS) or Unix. Instead it runs on top of an IBM batch operating system (OS/360, SVS, MVS). It takes the form of an editor with a Remote Job Entry system and thus has much the same relationship to the IBM operating systems as Emacs does to Unix. For these reasons WYLBUR is often thought of as a text editor rather than a time-sharing system. However, whereas Unix does not need Emacs to provide text editing services, IBM's operating systems originally needed WYLBUR. Later innovations such as IBM's Administrative Terminal System (ATS), Conversational Remote Batch Entry (CRBE), Conversational Remote Job Entry (CRJE) and Time Sharing Option (TSO) made WYLBUR less relevant for IBM users and gradually replaced it.
This article will use the full upper case spelling for commands and keywords. All references to characters and string assume an EBCDIC code page.
Use
ORVYL and WYLBUR were used at the Stanford Linear Accelerator Center (SLAC), the European Organization for Nuclear Resear |
https://en.wikipedia.org/wiki/Atriplex%20semibaccata | Atriplex semibaccata, commonly known as Australian saltbush, berry saltbush, or creeping saltbush, is a species of flowering plant in the family Amaranthaceae and is endemic to Australia. It is a perennial herb native to Western Australia, South Australia, Queensland and New South Wales, but has been introduced into other states and to overseas countries. It flowers and fruits in spring, and propagates from seed when the fruit splits open. This species of saltbush is adapted to inconsistent rainfall, temperature and humidity extremes and to poor soil. It is used for rehabilitation, medicine, as a cover crop and for fodder. Its introduction to other countries has had an environmental and economic impact on them.
Description
Atriplex semibaccata is a taproot perennial herb, that has prostrated and decumbent characteristics. Native to Australia and widespread in all mainland Australian states, A. semibaccata thrives in harsh and saline conditions. A. semibaccata is often mat-forming or semi-erect and can grow 40–80 cm tall, spanning a diameter of 1.5-2m. Its slender branches arise from a woody taproot.
Leaves are white scruffy, subsessile (small stalk) and are spatulate or obovate (oblong or elliptic) when the plant is young. Leaves develop a green to grey-green colour, with a length of 5-30mm and a width of 2-9mm, where the base is tapered and tip obtuse. Leaves are thin, oblong-elliptic, obtuse and have short petiolate (1–2 cm). Staminate flowers are tiny, terminal and 1.5mm wide, whereas pistillate flowers cluster distally from leaves. A. semibaccata is monoecious.
Fruiting bracteoles are red or orange when mature, as well as having a convex and rhombic shape (diamond like appearance). Fruits are succulent, united at base, margin toothed, sessile and are a length of 4-6mm.
A. semibaccata is seed propagated and seeds are dimorphic. Black seeds are 1.5-1.7mm, while brown seeds are 2mm in size. It can be used as fodder and is useful for degraded or salt affected l |
https://en.wikipedia.org/wiki/Monosodium%20citrate | Monosodium citrate, more correctly, sodium dihydrogen citrate (Latin: ), is an acid salt of citric acid. Disodium citrate and trisodium citrate are also known. It can be prepared by partial neutralisation of citric acid with an aqueous solution of sodium bicarbonate or carbonate. It has a slightly acidic taste.
NaHCO3 + C6H8O7 → NaC6H7O7 + CO2 + H2O
Na2CO3 + 2C6H8O7 → 2NaC6H7O7 + CO2 + H2O
It is highly soluble in water and practically insoluble in ethanol. Monosodium citrate is used as an anticoagulant in donated blood. It is used as an alkalinizing agent to prevent kidney stone disease. The crystals form as nearly perfect cubes. |
https://en.wikipedia.org/wiki/Disodium%20citrate | Disodium citrate, also known as disodium hydrogen citrate, Alkacitron, and sesquihydrate, is an acid salt of citric acid with the chemical formula Na2C6H6O7.
Uses
Food
It is used as an antioxidant in food and to improve the effects of other antioxidants. It is also used as an acidity regulator and sequestrant. Typical products include gelatin, jam, sweets, ice cream, carbonated beverages, milk powder, wine, and processed cheeses. Disodium citrate can also be used as a thickening agent or stabilizer.
Manufacturing
Disodium citrate can also be used as an ingredient in household products that remove stains.
Health
Disodium citrate may be used in patients to alleviate discomfort from urinary-tract infections. |
https://en.wikipedia.org/wiki/Ad%20Bax | Adriaan "Ad" Bax (born 1956) is a Dutch-American molecular biophysicist. He was born in the Netherlands and is the Chief of the Section on Biophysical NMR Spectroscopy at the National Institutes of Health. He is known for his work on the methodology of biomolecular NMR spectroscopy.
Biography
Bax was born in the Netherlands. He studied at Delft University of Technology where he got his engineer's degree (Ir. degree) in 1978, and Ph.D. degree in applied physics in 1981, after spending considerable time working with Ray Freeman at Oxford University. He worked as a postdoc with Gary Maciel at Colorado State University, before joining the NIH's Laboratory of Chemical Physics in 1983. In 1994 he became correspondent of the Royal Netherlands Academy of Arts and Sciences. He is currently the Chief of the Section on Biophysical NMR Spectroscopy at NIH. In 2002 he was elected a member of the National Academy of Sciences in the section on Biophysics and computational biology and a Fellow of the American Academy of Arts and Sciences. Bax was awarded the 2018 NAS Award for Scientific Reviewing and the 2018 Welch Award in Chemistry.
Work in NMR spectroscopy
Bax works in the field of biomolecular NMR spectroscopy, and has been involved in the development of many of the standard methods in the field. He collaborated extensively with fellow NIH scientists Marius Clore, Angela Gronenborn and Dennis Torchia in the development of multidimensional protein NMR. Bax is a pioneer in the development of triple resonance experiments and technology for resonance assignment of isotopically enriched proteins. He was also heavily involved in the development of using residual dipolar couplings and chemical shifts for determining RNA and protein structures.
Much of his recent work focuses on the roles of proteins in membranes.
He was the world's most cited chemist over two decades (1981-1997).
Work during COVID-19 pandemic
Using laser light scattering, Bax examined how speech-generated drople |
https://en.wikipedia.org/wiki/Nephrin | Nephrin is a protein necessary for the proper functioning of the renal filtration barrier. The renal filtration barrier consists of fenestrated endothelial cells, the glomerular basement membrane, and the podocytes of epithelial cells. Nephrin is a transmembrane protein that is a structural component of the slit diaphragm. They are present on the tips of the podocytes as an intricate mesh and convey strong negative charges which repel protein from crossing into the Bowman's space.
A defect in the gene for nephrin, NPHS1, is associated with congenital nephrotic syndrome of the Finnish type and causes massive amounts of protein to be leaked into the urine, or proteinuria. Nephrin is also required for cardiovascular development.
Interactions
Nephrin has been shown to interact with:
CASK,
CD2AP,
CDH3 and
CTNND1,
FYN,
KIRREL, and
NPHS2.
See also
Podocyte |
https://en.wikipedia.org/wiki/French%20Geodesic%20Mission%20to%20the%20Equator | The French Geodesic Mission to the Equator (), also called the French Geodesic Mission to Peru and the Spanish-French Geodesic Mission, was an 18th-century expedition to what is now Ecuador carried out for the purpose of performing an arc measurement, measuring the length of a degree of latitude near the Equator, by which the Earth radius can be inferred. The mission was one of the first geodesic (or geodetic) missions carried out under modern scientific principles, and the first major international scientific expedition.
Background
In the 18th century, there was significant debate in the scientific community, specifically in the French Academy of Sciences (Académie des sciences), as to whether the circumference of the Earth was greater around the Equator or around the poles. French astronomer Jacques Cassini held to the view that the polar circumference was greater. Louis XV of France and the academy sent two expeditions to determine the answer: one was sent to Meänmaa in Lapland, close to the Arctic Circle, under Swedish physicist Anders Celsius and French mathematician Pierre Maupertuis. The other mission was sent to Ecuador, at the Equator. Previous accurate measurements had been taken in Paris by Cassini and others.
Expedition
The equatorial mission was led by French astronomers Charles Marie de La Condamine, Pierre Bouguer, Louis Godin and Spanish geographers Jorge Juan and Antonio de Ulloa. They were accompanied by several assistants, including the naturalist Joseph de Jussieu and Louis's cousin Jean Godin. La Condamine was joined in his journey down the Amazon by Ecuadoran geographer and topographer Pedro Maldonado. (Maldonado later traveled to Europe to continue his scientific work.)
The Ecuadoran expedition
left France in May 1735. They landed on the Caribbean coast in Colombia, sailed to Panama where they traveled overland to the Pacific, and continued by sail to Ecuador, then called the Territory of Quito by Spain. In Ecuador, they split into tw |
https://en.wikipedia.org/wiki/Unitarity%20gauge | In theoretical physics, the unitarity gauge or unitary gauge is a particular choice of a gauge fixing in a gauge theory with a spontaneous symmetry breaking. In this gauge, the scalar fields responsible for the Higgs mechanism are transformed into a basis in which their Goldstone boson components are set to zero. In other words, the unitarity gauge makes the manifest number of scalar degrees of freedom minimal.
The gauge was introduced to particle physics by Steven Weinberg in the context of the electroweak theory. In electroweak theory, the degrees of freedom in a unitarity gauge are the massive spin-1 W+, W− and Z bosons with three polarizations each, the photon with two polarizations, and the scalar Higgs boson.
The unitarity gauge is usually used in tree-level calculations. For loop calculations, other gauge choices such as the 't Hooft–Feynman gauge often reduce the mathematical complexity of the calculation. |
https://en.wikipedia.org/wiki/Axino | The axino is a hypothetical elementary particle predicted by some theories of particle physics. Peccei–Quinn theory attempts to explain the observed phenomenon known as the strong CP problem by introducing a hypothetical real scalar particle called the axion. Adding supersymmetry to the model predicts the existence of a fermionic superpartner for the axion, the axino, and a bosonic superpartner, the saxion. They are all bundled up in a chiral superfield.
The axino has been predicted to be the lightest supersymmetric particle in such a model. In part due to this property, it is considered a candidate for the composition of dark matter.
The supermultiplet containing an axion and axino has been suggested as the origin of supersymmetry breaking, where the supermultiplet gains an F-term expectation value. |
https://en.wikipedia.org/wiki/Konishi%20anomaly | In theoretical physics, the Konishi anomaly is the violation of the conservation of the Noether current associated with certain transformations in theories with N=1 supersymmetry. More precisely, this transformation changes the phase of a chiral superfield. It shouldn't be confused with the R-symmetry that also depends on the fermionic superspace variables. The divergence of the corresponding Noether current for the Konishi transformation is nonzero but can be exactly expressed using the superpotential.
Konishi anomaly is named after its discoverer Kenichi Konishi, who is currently full professor of Theoretical Physics at the Physics Department E.Fermi of University of Pisa, Italy. |
https://en.wikipedia.org/wiki/R-symmetry | In theoretical physics, the R-symmetry is the symmetry transforming different supercharges in a theory with supersymmetry into each other. In the simplest case of the N=1 supersymmetry, such an R-symmetry is isomorphic to a global U(1) group or its discrete subgroup (for the Z2 subgroup it is called R-parity). For extended supersymmetry, the R-symmetry group becomes a global U(N) non-abelian group.
In a model that is classically invariant under both N=1 supersymmetry and conformal transformations, the closure of the superconformal algebra (at least on-shell) needs the introduction of a further bosonic generator that is associated to the R-symmetry. |
https://en.wikipedia.org/wiki/Harmonic%20superspace | In supersymmetry, harmonic superspace
is one way of dealing with supersymmetric theories with 8 real SUSY generators in a manifestly covariant manner. It turns out that the 8 real SUSY generators are pseudoreal, and after complexification, correspond to the tensor product of a four-dimensional Dirac spinor with the fundamental representation of SU(2)R. The quotient space , which is a 2-sphere/Riemann sphere.
Harmonic superspace describes N=2 D=4, N=1 D=5, and N=(1,0) D=6 SUSY in a manifestly covariant manner.
There are many possible coordinate systems over S2, but the one chosen not only involves redundant coordinates, but also happen to be a coordinatization of . We only get S2 after a projection over . This is of course the Hopf fibration. Consider the left action of SU(2)R upon itself. We can then extend this to the space of complex valued smooth functions over SU(2)R. In particular, we have the subspace of functions which transform as the fundamental representation under SU(2)R. The fundamental representation (up to isomorphism, of course) is a two-dimensional complex vector space. Let us denote the indices of this representation by i,j,k,...=1,2. The subspace of interest consists of two copies of the fundamental representation. Under the right action by U(1)R -- which commutes with any left action—one copy has a "charge" of +1, and the other of -1. Let us label the basis functions .
.
The redundancy in the coordinates is given by
.
Everything can be interpreted in terms of algebraic geometry. The projection is given by the "gauge transformation" where φ is any real number. Think of S3 as a U(1)R-principal bundle over S2 with a nonzero first Chern class. Then, "fields" over S2 are characterized by an integral U(1)R charge given by the right action of U(1)R. For instance, u+ has a charge of +1, and u− of -1. By convention, fields with a charge of +r are denoted by a superscript with r +'s, and ditto for fields with a charge of -r. R-charges are additive un |
https://en.wikipedia.org/wiki/Wess%E2%80%93Zumino%20gauge | In particle physics, the Wess–Zumino gauge is a particular choice of a gauge transformation in a gauge theory with supersymmetry. In this gauge, the supersymmetrized gauge transformation is chosen in such a way that most components of the vector superfield vanish, except for the usual physical ones when the function of the superspace is expanded in terms of components.
See also
Supersymmetric gauge theory
Supersymmetric quantum field theory
Gauge theories |
https://en.wikipedia.org/wiki/AIDA%20interactive%20educational%20freeware%20diabetes%20simulator | AIDA is a freeware computer program that permits the interactive simulation of plasma insulin and blood glucose profiles for demonstration, teaching, self-learning, and research purposes. Originally developed in 1991, it has been updated and enhanced since, and made available without charge from 1996 on the World Wide Web. The program, which is still being updated, has gone through a number of revisions and developments in the 16+ years since its original internet launch. During this time over 2.5 million visits have been logged at the AIDA Websites and more than 400,000 copies of the program have been downloaded. Further copies of the simulator have been made available, in the past, on diskette by the system developers and from the British Diabetic Association (BDA) — now called 'Diabetes UK' — London, England, following the BDA's own independent evaluation of the software. More than 1,075,000 diabetes simulations have been run via a web-based version of the AIDA diabetes simulator.
The AIDA software is intended to serve as an educational support tool and can be used by anyone — person with diabetes, relative of a patient, health care professional (doctor, nurse, clinical diabetes educator, dietician, pharmacist, etc.), or student — even if they may have minimal knowledge of the pathophysiology of diabetes mellitus.
Overview of AIDA physiological model
AIDA has been described in detail in the medical / scientific / computing / diabetes literature. It incorporates a compartmental model that describes glucose-insulin interaction in people completely lacking endogenous insulin secretion — i.e. insulin-dependent patients with type 1 diabetes mellitus. The AIDA model contains a single extra-cellular glucose compartment into which glucose enters via both absorption from the intestine and glucose production from the liver. The model also contains separate compartments for plasma and 'active' insulin, the latter being responsible for glycemic control while insu |
https://en.wikipedia.org/wiki/Quasi-set%20theory | Quasi-set theory is a formal mathematical theory for dealing with collections of objects, some of which may be indistinguishable from one another. Quasi-set theory is mainly motivated by the assumption that certain objects treated in quantum physics are indistinguishable and don't have individuality.
Motivation
The American Mathematical Society sponsored a 1974 meeting to evaluate the resolution and consequences of the 23 problems Hilbert proposed in 1900. An outcome of that meeting was a new list of mathematical problems, the first of which, due to Manin (1976, p. 36), questioned whether classical set theory was an adequate paradigm for treating collections of indistinguishable elementary particles in quantum mechanics. He suggested that such collections cannot be sets in the usual sense, and that the study of such collections required a "new language".
The use of the term quasi-set follows a suggestion in da Costa's 1980 monograph Ensaio sobre os Fundamentos da Lógica (see da Costa and Krause 1994), in which he explored possible semantics for what he called "Schrödinger Logics". In these logics, the concept of identity is restricted to some objects of the domain, and has motivation in Schrödinger's claim that the concept of identity does not make sense for elementary particles (Schrödinger 1952). Thus in order to provide a semantics that fits the logic, da Costa submitted that "a theory of quasi-sets should be developed", encompassing "standard sets" as particular cases, yet da Costa did not develop this theory in any concrete way. To the same end and independently of da Costa, Dalla Chiara and di Francia (1993) proposed a theory of quasets to enable a semantic treatment of the language of microphysics. The first quasi-set theory was proposed by D. Krause in his PhD thesis, in 1990 (see Krause 1992). A related physics theory, based on the logic of adding fundamental indistinguishability to equality and inequality, was developed and elaborated independently in t |
https://en.wikipedia.org/wiki/Ultrafiltration%20%28kidney%29 | In renal physiology, ultrafiltration occurs at the barrier between the blood and the filtrate in the glomerular capsule (Bowman's capsule) in the kidneys. As in nonbiological examples of ultrafiltration, pressure (in this case blood pressure) and concentration gradients lead to a separation through a semipermeable membrane (provided by the podocytes). The Bowman's capsule contains a dense capillary network called the glomerulus. Blood flows into these capillaries through the afferent arterioles and leaves through the efferent arterioles.
The high hydrostatic pressure forces small molecules in the tubular fluid such as water, glucose, amino acids, sodium chloride and urea through the filter, from the blood in the glomerular capsule across the basement membrane of the Bowman's capsule and into the renal tubules. This process is called ultrafiltration; the resulting fluid, virtually free of large proteins and blood cells, is referred to as glomerular filtrate, or ultrafiltrate. Further modification of ultrafiltrate, by reabsorption and secretion, transforms it into urine.
Glomerular pressure is about 75 millimeters of mercury (10 kPa). It is opposed by osmotic pressure (30 mmHg, 4.0 kPa) and hydrostatic pressure (20 mmHg, 2.7 kPa) of solutes present in capsular space. This difference in pressure is called effective pressure (25 mmHg, 3.3 kPa).
In hemodialysis centers, ultrafiltration takes place in a hemofilter on the hemodialysis machines, when the blood pressure is greater than the dialysate pressure (difference = transmembrane pressure (TMP)). This removes fluid from the blood while keeping its blood cells intact.
Selectivity
The structures of the layers of the glomerulus determine their permeability-selectivity (permselectivity). For instance, small ions such as sodium and potassium pass freely, while larger plasma proteins, such as hemoglobin tetramers, haptoglobin bound hemoglobin and albumin have practically no permeability at all. Also, negatively charged |
https://en.wikipedia.org/wiki/Multiple%20Access%20with%20Collision%20Avoidance%20for%20Wireless | Multiple Access with Collision Avoidance for Wireless (MACAW) is a slotted medium access control (MAC) protocol widely used in ad hoc networks. Furthermore, it is the foundation of many other MAC protocols used in wireless sensor networks (WSN). The IEEE 802.11 RTS/CTS mechanism is adopted from this protocol. It uses RTS-CTS-DS-DATA-ACK frame sequence for transferring data, sometimes preceded by an RTS-RRTS frame sequence, in view to provide solution to the hidden node problem. Although protocols based on MACAW, such as S-MAC, use carrier sense in addition to the RTS/CTS mechanism, MACAW does not make use of carrier sense.
Principles of operation
Assume that node A has data to transfer to node B. Node A initiates the process by sending a Request to Send frame (RTS) to node B. The destination node (node B) replies with a Clear To Send frame (CTS). After receiving CTS, node A sends data. After successful reception, node B replies with an acknowledgement frame (ACK). If node A has to send more than one data fragment, it has to wait a random time after each successful data transfer and compete with adjacent nodes for the medium using the RTS/CTS mechanism.
Any node overhearing an RTS frame (for example node F or node E in the illustration) refrains from sending anything until a CTS is received, or after waiting a certain time. If the captured RTS is not followed by a CTS, the maximum waiting time is the RTS propagation time and the destination node turnaround time.
Any node (node C and node E) overhearing a CTS frame refrains from sending anything for the time until the data frame and ACK should have been received (solving the hidden terminal problem), plus a random time. Both the RTS and CTS frames contain information about the length of the DATA frame. Hence a node uses that information to estimate the time for the data transmission completion.
Before sending a long DATA frame, node A sends a short Data-Sending frame (DS), which provides information about the |
https://en.wikipedia.org/wiki/European%20Physical%20Journal%20C | The European Physical Journal C (EPJ C) is a biweekly peer-reviewed, open access scientific journal covering theoretical and experimental physics. It is part of the SCOAP3 initiative.
See also
European Physical Journal |
https://en.wikipedia.org/wiki/Introduction%20to%20Commutative%20Algebra | Introduction to Commutative Algebra is a well-known commutative algebra textbook written by Michael Atiyah and Ian G. Macdonald. It deals with elementary concepts of commutative algebra including localization, primary decomposition, integral dependence, Noetherian and Artinian rings and modules, Dedekind rings, completions and a moderate amount of dimension theory. It is notable for being among the shorter English-language introductory textbooks in the subject, relegating a good deal of material to the exercises.
(Hardcover 1969, ) (Paperback 1994, )
1969 non-fiction books
Mathematics textbooks
Commutative algebra |
https://en.wikipedia.org/wiki/Talkboy | Talkboy is a line of handheld voice recorder and sound novelty toys manufactured by Tiger Electronics in the 1990s. The brand began as a result of a promotional tie-in with the 1992 film Home Alone 2: Lost in New York; the most well-known product was the Deluxe Talkboy, a cassette recorder and player with a variable-speed voice changer that caused toy crazes over several holiday shopping seasons beginning in 1993.
The Talkboy was originally conceived as a prop for Home Alone 2 for the lead character Kevin MacCallister to use to outsmart adults. At the request of writer John Hughes and distributor 20th Century Fox, Tiger designed and built the prop. The company was given permission by the movie studio to sell a retail version of the toy, and it released two cassette recorders modeled after the film prop in 1992 and 1993, respectively. The original model did not have the voice changer of the film version and sold only moderately during the 1992 holiday shopping season. Tiger added the feature to the Deluxe model, which was released in April 1993. Following the release of Home Alone 2 on home video in July and a cross-promotion with Life cereal, interest in the toy spiked. Retailers had severely underestimated demand, and as a result the Deluxe Talkboy was one of the most highly sought-after toys during the 1993 holiday shopping season, selling out of stores across the United States. The product continued to be a best-seller in subsequent holiday shopping seasons. A pink version of the cassette recorder called Deluxe Talkgirl was released in 1995.
The success of the Talkboy cassette recorders spawned a product line of electronic sound novelty toys, including a phone, walkie talkies, and a radio. For subsequent recording devices, Tiger transitioned to digital technology, using solid-state storage and adding sound effects, beginning with Talkboy/Talkgirl F/X+ pens in 1995, which sold more than a million units in 45 days.
Origin as movie prop
The original Talkboy mode |
https://en.wikipedia.org/wiki/Igusa%20zeta%20function | In mathematics, an Igusa zeta function is a type of generating function, counting the number of solutions of an equation, modulo p, p2, p3, and so on.
Definition
For a prime number p let K be a p-adic field, i.e. , R the valuation ring and P the maximal ideal. For we denote by the valuation of z, , and for a uniformizing parameter π of R.
Furthermore let be a Schwartz–Bruhat function, i.e. a locally constant function with compact support and let be a character of .
In this situation one associates to a non-constant polynomial the Igusa zeta function
where and dx is Haar measure so normalized that has measure 1.
Igusa's theorem
showed that is a rational function in . The proof uses Heisuke Hironaka's theorem about the resolution of singularities. Later, an entirely different proof was given by Jan Denef using p-adic cell decomposition. Little is known, however, about explicit formulas. (There are some results about Igusa zeta functions of Fermat varieties.)
Congruences modulo powers of
Henceforth we take to be the characteristic function of and to be the trivial character. Let denote the number of solutions of the congruence
.
Then the Igusa zeta function
is closely related to the Poincaré series
by |
https://en.wikipedia.org/wiki/Degloving | A degloving injury is a type of avulsion in which an extensive section of skin is completely torn off the underlying tissue, severing its blood supply. It is named by analogy to the process of removing a glove.
The causes of degloving can vary, but they often occur when someone's hand or arm gets stuck in a machine or when they are involved in a car crash. Treatment for degloving injuries can vary depending on the severity of the injury, but often includes surgery and skin grafts.
All sorts of events can lead to this type of injury. Car crashes, falls, or getting caught in machinery are all common causes. However, there are also less obvious things that can cause degloving injuries, like contact with chemicals or extreme weather conditions.
Effects
Typically, degloving injuries affect the extremities and limbs; in these cases, they are frequently associated with underlying fractures. Any injury which would induce degloving of the head or torso is likely to be lethal. However, controlled facial degloving is often featured in plastic surgery.
Degloving injuries invariably require major surgical interventions. Treatment options include replantation or revascularization of the degloved skins, or when these are not possible, skin grafts or skin flaps. While the preservation of the extremities and limbs is normally preferred, in some cases amputations may be advised or required. Post-operative physiotherapy is of particular importance for degloving injuries involving the hand.
Other animals
Many small mammals are able to induce degloving of their tails to escape capture; this is comparable to tail autotomy in reptiles. |
https://en.wikipedia.org/wiki/CRC%20Handbook%20of%20Chemistry%20and%20Physics | The CRC Handbook of Chemistry and Physics is a comprehensive one-volume reference resource for science research. First published in 1914, it is currently () in its 103rd edition, published in 2022. It is sometimes nicknamed the "Rubber Bible" or the "Rubber Book", as CRC originally stood for "Chemical Rubber Company".
As late as the 1962–1963 edition (3604 pages) the Handbook contained myriad information for every branch of science and engineering. Sections in that edition include: Mathematics, Properties and Physical Constants, Chemical Tables, Properties of Matter, Heat, Hygrometric and Barometric Tables, Sound, Quantities and Units, and Miscellaneous. Earlier editions included sections such as "Antidotes of Poisons", "Rules for Naming Organic Compounds", "Surface Tension of Fused Salts", "Percent Composition of Anti-Freeze Solutions", "Spark-gap Voltages", "Greek Alphabet", "Musical Scales", "Pigments and Dyes", "Comparison of Tons and Pounds", "Twist Drill and Steel Wire Gauges" and "Properties of the Earth's Atmosphere at Elevations up to 160 Kilometers". Later editions focus almost exclusively on chemistry and physics topics and eliminated much of the more "common" information.
Contents by edition
22nd–44th Editions
Section A: Mathematical Tables
Section B: Properties and Physical Constants
Section C: General Chemical Tables/Specific Gravity and Properties of Matter
Section D: Heat and Hygrometry/Sound/Electricity and Magnetism/Light
Section E: Quantities and Units/Miscellaneous
Index
45th–70th Editions
Section A: Mathematical Tables
Section B: Elements and Inorganic Compounds
Section C: Organic Compounds
Section D: General Chemical
Section E: General Physical Constants
Section F: Miscellaneous
Index
71st–102nd Editions
Section 1: Basic Constants, Units, and Conversion Factors
Section 2: Symbols, Terminology, and Nomenclature
Section 3: Physical Constants of Organic Compounds
Section 4: Properties of the Elements and Inorganic Com |
https://en.wikipedia.org/wiki/Z800%203DVisor | The Z800 3DVisor is a head-mounted display manufactured by eMagin since 2005.
Overview
The main part of the Z800 is a pair of OLED displays with magnifying lenses producing a 40-degree diagonal field of view for each eye, used to display stereoscopic images with a fixed resolution of 800x600 pixels, through the use of the nVidia stereo 3D drivers, or, using later firmware revisions, any source of alternating frames. The visor can also be used as a 2D portable monitor on computers not equipped with an nVidia video card, using another operating system, or Macintoshes.
The visor is equipped with a NEC TOKIN combined accelerometer/magnetometer/rate gyroscope 3-degrees of freedom motion sensor used to emulate mouse movements (typically to look around in first-person shooters), a pair of ear buds and an integrated microphone.
See also
Virtual reality
3D stereo view
External links
eMagin Website
Z800 3DVisor site
Linux Alpha Drivers
VR Viewer Headsets
Display technology
Multimodal interaction
Virtual reality headsets
Display devices |
https://en.wikipedia.org/wiki/Fusion%20torch | A fusion torch is a technique for utilizing the high-temperature plasma of a fusion reactor to break apart other materials (especially waste materials) and convert them into a few reusable and saleable elements. It was invented in 1968 by Bernard J. Eastlund and William C. Gough while they were program managers of the controlled thermonuclear research program of the United States Atomic Energy Commission (AEC). The basic concept was to impinge the plasma leaking from fusion reactors onto solids or liquids, vaporizing, dissociating and ionizing the materials, then separating the resulting elements into separate bins for collection. Other applications of fusion plasmas such as generation of UV and optical light, and generation of hydrogen fuel, were also described in their associated 1969 paper.
How it works
The process began with a tokamak, a doughnut-shaped magnetic "bottle", containing plasma and unwanted material. This combination would result in a pool of electrons and nuclei which in turn would cause the tokamak to overflow and transfer the plasma into an outlet. This plasma then passes through a series of metal plates, differing in particular temperatures, all arranged in descending order. The atoms of elements pass over the plates with boiling points above their own. Eventually, the atoms encounter plates where the temperature is lower than their boiling point. This makes them stick onto the plate. The plates then work as a distillation system which sorts the plasma into its constituent elements. These pure elements can then be reused.
1969 paper
In the paper "The Fusion Torch – Closing the Cycle from Use to Reuse", Bernard J. Eastlund and William C. Gough defined population (food), entropy (resources, energy, pollution), and war (human needs and behavior) as three traps that could hamper the advancement of mankind.
In terms of energy needs they estimated that by the year 2000 they would need 140,000 megawatts of electrical capacity. They also speculated |
https://en.wikipedia.org/wiki/Absorption%20%28skin%29 | Skin absorption is a route by which substances can enter the body through the skin. Along with inhalation, ingestion and injection, dermal absorption is a route of exposure for toxic substances and route of administration for medication. Absorption of substances through the skin depends on a number of factors, the most important of which are concentration, duration of contact, solubility of medication, and physical condition of the skin and part of the body exposed.
Skin (percutaneous, dermal) absorption is the transport of chemicals from the outer surface of the skin both into the skin and into circulation. Skin absorption relates to the degree of exposure to and possible effect of a substance which may enter the body through the skin. Human skin comes into contact with many agents intentionally and unintentionally. Skin absorption can occur from occupational, environmental, or consumer skin exposure to chemicals, cosmetics, or pharmaceutical products. Some chemicals can be absorbed in enough quantity to cause detrimental systemic effects. Skin disease (dermatitis) is considered one of the most common occupational diseases. In order to assess if a chemical can be a risk of either causing dermatitis or other more systemic effects and how that risk may be reduced, one must know the extent to which it is absorbed. Thus, dermal exposure is a key aspect of human health risk assessment.
Factors influencing absorption
Along with inhalation, ingestion and injection, dermal absorption is a route of exposure for bioactive substances including medications. Absorption of substances through the skin depends on a number of factors:
Concentration
Molecular weight of the molecule
Duration of contact
Solubility of substance
Physical condition of the skin
Part of the body exposed including the amount of hair on the skin
In general, the rate of absorption of chemicals through skin follows the following scheme from fastest to slowest: Scrotal > Forehead > Armpit ≥ Scalp > B |
https://en.wikipedia.org/wiki/Eye%20movement%20in%20music%20reading | Eye movement in music reading is the scanning of a musical score by a musician's eyes. This usually occurs as the music is read during performance, although musicians sometimes scan music silently to study it. The phenomenon has been studied by researchers from a range of backgrounds, including cognitive psychology and music education. These studies have typically reflected a curiosity among performing musicians about a central process in their craft, and a hope that investigating eye movement might help in the development of more effective methods of training musicians' sight reading skills.
A central aspect of music reading is the sequence of alternating saccades and fixations, as it is for most oculomotor tasks. Saccades are the rapid ‘flicks’ that move the eyes from location to location over a music score. Saccades are separated from each other by fixations, during which the eyes are relatively stationary on the page. It is well established that the perception of visual information occurs almost entirely during fixations and that little if any information is picked up during saccades. Fixations comprise about 90% of music reading time, typically averaging 250–400 ms in duration.
Eye movement in music reading is an extremely complex phenomenon that involves a number of unresolved issues in psychology, and which requires intricate experimental conditions to produce meaningful data. Despite some 30 studies in this area over the past 70 years, little is known about the underlying patterns of eye movement in music reading.
Relationship with eye movement in language reading
Eye movement in music reading may at first appear to be similar to that in language reading, since in both activities the eyes move over the page in fixations and saccades, picking up and processing coded meanings. However, it is here that the obvious similarities end. Not only is the coding system of music nonlinguistic; it involves what is apparently a unique combination of features among hu |
https://en.wikipedia.org/wiki/Regulon | In molecular genetics, a regulon is a group of genes that are regulated as a unit, generally controlled by the same regulatory gene that expresses a protein acting as a repressor or activator. This terminology is generally, although not exclusively, used in reference to prokaryotes, whose genomes are often organized into operons; the genes contained within a regulon are usually organized into more than one operon at disparate locations on the chromosome. Applied to eukaryotes, the term refers to any group of non-contiguous genes controlled by the same regulatory gene.
A modulon is a set of regulons or operons that are collectively regulated in response to changes in overall conditions or stresses, but may be under the control of different or overlapping regulatory molecules. The term stimulon is sometimes used to refer to the set of genes whose expression responds to specific environmental stimuli.
Examples
Commonly studied regulons in bacteria are those involved in response to stress such as heat shock. The heat shock response in E. coli is regulated by the sigma factor
σ32 (RpoH), whose regulon has been characterized as containing at least 89 open reading frames.
Regulons involving virulence factors in pathogenic bacteria are of particular research interest; an often-studied example is the phosphate regulon in E. coli, which couples phosphate homeostasis to pathogenicity through a two-component system. Regulons can sometimes be pathogenicity islands.
The Ada regulon in E. coli is a well-characterized example of a group of genes involved in the adaptive response form of DNA repair.
Quorum sensing behavior in bacteria is a commonly cited example of a modulon or stimulon, though some sources describe this type of intercellular auto-induction as a separate form of regulation.
Evolution
Changes in the regulation of gene networks are a common mechanism for prokaryotic evolution. An example of the effects of different regulatory environments for homologous protei |
https://en.wikipedia.org/wiki/Eye%20movement%20in%20reading | Eye movement in reading involves the visual processing of written text. This was described by the French ophthalmologist Louis Émile Javal in the late 19th century. He reported that eyes do not move continuously along a line of text, but make short, rapid movements (saccades) intermingled with short stops (fixations). Javal's observations were characterised by a reliance on naked-eye observation of eye movement in the absence of technology. From the late 19th to the mid-20th century, investigators used early tracking technologies to assist their observation, in a research climate that emphasised the measurement of human behaviour and skill for educational ends. Most basic knowledge about eye movement was obtained during this period. Since the mid-20th century, there have been three major changes: the development of non-invasive eye-movement tracking equipment; the introduction of computer technology to enhance the power of this equipment to pick up, record, and process the huge volume of data that eye movement generates; and the emergence of cognitive psychology as a theoretical and methodological framework within which reading processes are examined. Sereno & Rayner (2003) believed that the best current approach to discover immediate signs of word recognition is through recordings of eye movement and event-related potential.
History
Until the second half of the 19th century, researchers had at their disposal three methods of investigating eye movement. The first, unaided observation, yielded only small amounts of data that would be considered unreliable by today's scientific standards. This lack of reliability arises from the fact that eye movement occurs frequently, rapidly, and over small angles, to the extent that it is impossible for an experimenter to perceive and record the data fully and accurately without technological assistance. The other method was self-observation, now considered to be of doubtful status in a scientific context. Despite this, some kn |
https://en.wikipedia.org/wiki/Kinetoplast | A kinetoplast is a network of circular DNA (called kDNA) inside a mitochondrion that contains many copies of the mitochondrial genome. The most common kinetoplast structure is a disk, but they have been observed in other arrangements. Kinetoplasts are only found in Excavata of the class Kinetoplastida. The variation in the structures of kinetoplasts may reflect phylogenic relationships between kinetoplastids. A kinetoplast is usually adjacent to the organism's flagellar basal body, suggesting that it is bound to some components of the cytoskeleton. In Trypanosoma brucei this cytoskeletal connection is called the tripartite attachment complex and includes the protein p166.
Trypanosoma
In trypanosomes, a group of flagellated protozoans, the kinetoplast exists as a dense granule of DNA within the mitochondrion. Trypanosoma brucei, the parasite which causes African trypanosomiasis (African sleeping sickness), is an example of a trypanosome with a kinetoplast. Its kinetoplast is easily visible in samples stained with DAPI, a fluorescent DNA stain, or by the use of fluorescent in situ hybridization (FISH) with BrdU, a thymidine analogue.
Structure
The kinetoplast contains circular DNA in two forms, maxicircles and minicircles. Maxicircles are between 20 and 40kb in size and there are a few dozen per kinetoplast. There are several thousand minicircles per kinetoplast and they are between 0.5 and 1kb in size. Maxicircles encode the typical protein products needed for the mitochondria which is encrypted. Herein lies the only known function of the minicircles - producing guide RNA (gRNA) to decode this encrypted maxicircle information, typically through the insertion or deletion of uridine residues. The network of maxicircles and minicircles are catenated to form a planar network that resembles chain mail. Reproduction of this network then requires that these rings be disconnected from the parental kinetoplast and subsequently reconnected in the daughter kinetoplast. This u |
https://en.wikipedia.org/wiki/Peptide%20sequence%20tag | A peptide sequence tag is a piece of information about a peptide obtained by tandem mass spectrometry that can be used to identify this peptide in a protein database.
Mass spectrometry
In general, peptides can be identified by fragmenting them in a mass spectrometer. For example, during collision-induced dissociation peptides collide with a gas within the mass spectrometer and break into pieces at their peptide bonds. The resulting fragment ions (called b-ions and y-ions) have mass differences corresponding to the residue masses of the respective amino acids. Thus, a tandem mass spectrum contains partial information about the amino acid sequence of the peptide. The peptide sequence tag approach, developed by Matthias Wilm and Matthias Mann at the EMBL, uses this information to identify the peptide in a database. Briefly, a couple of masses are extracted from the spectrum in order to obtain the peptide sequence tag. This peptide sequence tag is a unique identifier of a specific peptide and can be used to find it in a database containing all possible peptide sequences.
Peptide fragment notation
A notation has been developed for indicating peptide fragments that arise from a tandem mass spectrum. Peptide fragment ions are indicated by a, b, or c if the charge is retained on the N-terminus and by x, y or z if the charge is maintained on the C-terminus. The subscript indicates the number of amino acid residues in the fragment. Prime symbols indicate the number of protons or hydrogens added to the fragment to form the observed ion. For example, y'' denotes the singly charged ion analogous to a protonated peptide, (y''')2+ is a doubly charged ion analogous to a doubly protonated peptide.
See also
Protein sequence
Protein mass spectrometry |
https://en.wikipedia.org/wiki/Alveolar%20macrophage | An alveolar macrophage, pulmonary macrophage, (or dust cell) is a type of macrophage, a professional phagocyte, found in the airways and at the level of the alveoli in the lungs, but separated from their walls.
Activity of the alveolar macrophage is relatively high, because they are located at one of the major boundaries between the body and the outside world. They are responsible for removing particles such as dust or microorganisms from the respiratory surfaces.
Alveolar macrophages are frequently seen to contain granules of exogenous material such as particulate carbon that they have picked up from respiratory surfaces. Such black granules may be especially common in smoker's lungs or long-term city dwellers.
The alveolar macrophage is the third cell type in the alveolus; the others are the type I and type II pneumocytes.
Comparison of pigmented pulmonary macrophages
Function
Alveolar macrophages are phagocytes that play a critical role in homeostasis, host defense, and tissue remodeling. Their population density is decisive for these many processes. They are highly adaptive and can release many secretions, to interact with other cells and molecules using several surface receptors. Alveolar macrophages are also involved in the phagocytosis of apoptotic and necrotic cells. They need to be selective of the material that is phagocytized to safeguard the normal cells and structures. To combat infection, the phagocytes facilitate many pattern recognition receptors (PRRs) to help recognize pathogen-associated molecular patterns (PAMPs) on the surface of pathogenic microorganisms. PAMPs all have the common features of being unique to a group of pathogens but invariant in their basic structure; and are essential for pathogenicity (ability of an organism to produce an infectious disease in another organism). Proteins involved in microbial pattern recognition include mannose receptor, complement receptors, DC-SIGN, Toll-like receptors(TLRs), the scavenger receptor, C |
https://en.wikipedia.org/wiki/Trabecular%20arteries | The trabecular arteries are the name of the branches of the splenic artery after it passes into the trabeculae of the spleen, where it branches.
When these arteries then reach the white pulp, and become covered with periarteriolar lymphoid sheaths, the name changes again to central arteries (or central arterioles). Branches of the central arteries are given to the red pulp, and these are called penicillar arteries).
Details
The lienal artery is remarkable for its large size in proportion to the size of the organ, and also for its tortuous course. It divides into six or more branches, which enter the hilum of the spleen and ramify throughout its substance, receiving sheaths from an involution of the external fibrous tissue.
Similar sheaths also invest the nerves and veins.
Each branch runs in the transverse axis of the organ, from within outward, diminishing in size during its transit, and giving off in its passage smaller branches, some of which pass to the anterior, others to the posterior part.
These ultimately leave the trabecular sheaths, and terminate in the proper substance of the spleen in small tufts or pencils of minute arterioles, which open into the interstices of the reticulum formed by the branched sustentacular cells.
Each of the larger branches of the artery supplies chiefly that region of the organ in which the branch ramifies, having no anastomosis with the majority of the other branches.
The arterioles, supported by the minute trabeculae, traverse the pulp in all directions in bundles (penicilli) of straight vessels.
Their trabecular sheaths gradually undergo a transformation, become much thickened, and converted into adenoid tissue; the bundles of connective tissue becoming looser and their fibrils more delicate, and containing in their interstices an abundance of lymph corpuscles.
The altered coat of the arterioles, consisting of adenoid tissue, presents here and there thickenings of a spheroidal shape, the white pulp.
The arterioles end |
https://en.wikipedia.org/wiki/Trabecular%20veins | The trabecular veins are the largest veins inside the spleen. They drain the blood collected in the sinuses of the pulp.
Details
The blood is collected from the interstices of the splenic tissue by the rootlets of the veins, which begin much in the same way as the arteries end.
The connective-tissue corpuscles of the pulp arrange themselves in rows, in such a way as to form an elongated space or sinus.
They become elongated and spindle-shaped, and overlap each other at their extremities, and thus form a sort of endothelial lining of the path or sinus, which is the radicle of a vein.
On the outer surfaces of these cells are seen delicate transverse lines or markings, which are due to minute elastic fibrils arranged in a circular manner around the sinus.
Thus the channel obtains an external investment, and gradually becomes converted into a small vein, which after a short course acquires a coat of ordinary connective tissue, lined by a layer of flattened epithelial cells which are continuous with the supporting cells of the pulp.
The smaller veins unite to form larger veins that do not accompany the arteries, but soon enter the trabecular sheaths of the capsule, and by their junction form six or more branches, which emerge from the splenic hilum, and, uniting, constitute the splenic vein, the largest radicle of the portal vein. |
https://en.wikipedia.org/wiki/Grand%20mean | The grand mean or pooled mean is the average of the means of several subsamples, as long as the subsamples have the same number of data points. For example, consider several lots, each containing several items. The items from each lot are sampled for a measure of some variable and the means of the measurements from each lot are computed. The mean of the measures from each lot constitutes the subsample mean. The mean of these subsample means is then the grand mean.
Example
Suppose there are three groups of numbers: group A has 2, 6, 7, 11, 4; group B has 4, 6, 8, 14, 8; group C has 8, 7, 4, 1, 5.
The mean of group A = (2+6+7+11+4)/5 = 6,
The mean of group B = (4+6+8+14+8)/5 = 8,
The mean of group C = (8+7+4+1+5)/5 = 5,
Therefore, the grand mean of all numbers = (6+8+5)/3 = 6.333.
Application
Suppose one wishes to determine which states in America have the tallest men. To do so, one measures the height of a suitably sized sample of men in each state. Next, one calculates the means of height for each state, and then the grand mean (the mean of the state means) as well as the corresponding standard deviation of the state means. Now, one has the necessary information for a preliminary determination of which states have abnormally tall or short men by comparing the means of each state to the grand mean ± some multiple of the standard deviation.
In ANOVA, there is a similar usage of grand mean to calculate sum of squares (SSQ), a measurement of variation. The total variation is defined as the sum of squared differences between each score and the grand mean (designated as GM), given by the equation
Discussion
The term grand mean is used for two different concepts that should not be confused, namely, the overall mean and the mean of means. The overall mean (in a grouped data set) is equal to the sample mean, namely, . The mean of means is literally the mean of the G (g=1,...,G) group means , namely, . If the sample sizes across the G groups are equal, then the t |
https://en.wikipedia.org/wiki/Cauzin%20Softstrip | Cauzin Softstrip was the first commercial 2D barcode format. Introduced in 1985, it could store up to 1000 bytes per square inch, which was 20 to 100 times more than the bar codes of the day. It was designed to allow magazines to distribute computer programs by simply printing a pattern on a page. Several computer magazines printed Softstrip data that encoded program source listings, or even executable programs. It is now known as Datastrip code.
Softstrip format never became very popular for program distribution. It was intended to replace the tedium of entering type-in programs from magazines, but the format encoded less than a thousand bytes per square inch, which meant that large files took up a lot of space in a magazine. The bar codes didn't work well if the magazine ink was smeared; and the reader hardware was relatively expensive at around US$200. The high cost of the unit and the added demands placed on publishers led to a chicken or egg dilemma between supply and demand where magazines were reluctant to publish listings in Softstrip format until there was a sizable user base, and users waited for the bar codes to become common in magazines before buying the unit.
More recently, other applications for the code have been developed, including its use on identification cards and similar documents to encode text and biometric data. |
https://en.wikipedia.org/wiki/Libdmc | Libdmc is a library designed at the LIP6 laboratory. Its goal is to ease the distribution of existing model checkers. It has also been designed to provide the most generic interfaces, without sacrificing performance, thanks to the C++ language.
Model checking offers a way to automatically prove that a modeled system behavior is correct by verifying properties. However, it suffers from the so-called state space explosion problem, caused by an intensive use of memory. Many solutions have been proposed to overcome this problem (e.g. symbolic representations with decisions diagrams - like BDD) but these methods can rapidly lead to an unacceptable time consumption.
Distributed model checking is a way to overcome both memory and time consumptions by using aggregated resources of a dedicated cluster. However, re-writing an entire model checker is a difficult task, so the approach of libdmc is to give a framework in order to construct a model checker. |
https://en.wikipedia.org/wiki/Fiador%20knot | The fiador knot (also Theodore knot) is a decorative, symmetrical knot used in equine applications to create items such as rope halters, hobbles, and components of the fiador on some hackamore designs. As traditionally described, it is a four strand diamond knot in which six of the eight ends loop back into the knot, thus allowing it to be tied with a single line. While a specific knot is discussed in this article, the fiador knot has also been treated as an entire class of multi-strand knots similarly made with a single line.
Etymology
The origin of the variant name "Theodore knot", used in the United States, is a corruption of the Spanish fiador. American cowboys likewise corrupted a number of other closely related terms, substituting "hackamore" for jaquima and "McCarty" for mecate.
Knotting authority Clifford Ashley relates Philip Ashton Rollins's suggestion that, "When Theodore Roosevelt, 'the hero of San Juan Hill,' visited the Southwest, shortly after the Spanish–American War, it was a foregone conclusion that the Spanish name 'Fiador' would be corrupted to 'Theodore' in his honor."
Tying
Considered a difficult knot to tie, cowboys were said to have been able to collect a fee for tying it. Ashley went so far as to include it in a chapter covering trick knots in The Ashley Book of Knots stating archly, "the trick is to succeed in tying it."
Many methods have been devised to tie the fiador knot, including fixtures used to hold the parts in shape while tying. More recent sources have shown a simpler method of forming the fiador knot using a flat precursor knot.
The following images show a method for tying the fiador knot:
Tight face and loose face
Careful inspection reveals the two faces of the completed fiador knot, where the four strands emerge, are not identical. One has the appearance of a crown knot surrounding the emerging strands and is somewhat resistant to spreading when they are pulled apart. By comparison, the strands emerging from the |
https://en.wikipedia.org/wiki/Multi-project%20wafer%20service | Multi-project chip (MPC), and multi-project wafer (MPW) semiconductor manufacturing arrangements allow customers to share mask and microelectronics wafer fabrication cost between several designs or projects.
With the MPC arrangement, one chip is a combination of several designs and this combined chip is then repeated all over the wafer during the manufacturing. MPC arrangement produces typically roughly equal number of chip designs per wafer.
With the MPW arrangement, different chip designs are aggregated on a wafer, with perhaps a different number of designs/projects per wafer. This is made possible with novel mask making and exposure systems in photolithography during IC manufacturing. MPW builds upon the older MPC procedures and enables more effective support for different phases and needs of manufacturing volumes of different designs/projects. MPW arrangement support education, research of new circuit architectures and structures, prototyping and even small volume production.
Worldwide, several MPW services are available from companies, semiconductor foundries and from government-supported institutions. Originally both MPC and MPW arrangements were introduced for integrated circuit (IC) education and research; some MPC/MPW services/gateways are aimed for non-commercial use only. Currently MPC/MPW services are effectively used for system on a chip integration. Selecting the right service platform at the prototyping phase ensures gradual scaling up production via MPW services taking into account the rules of the selected service.
MPC/MPW arrangements have also been applied to microelectromechanical systems (MEMS), integrated photonics like silicon photonics fabrication and microfluidics.
A refinement of MPW is multi-layer mask (MLM) arrangement, where a limited number of masks (e.g. 4) are changed during manufacturing at exposure phase. The rest of the masks are the same from the chip to chip on the whole wafer. MLM approach is well suited for several specifi |
https://en.wikipedia.org/wiki/Tunica%20externa | The tunica externa (Neo-Latin "outer coat"), also known as the tunica adventitia (Neo-Latin "additional coat"), is the outermost tunica (layer) of a blood vessel, surrounding the tunica media. It is mainly composed of collagen and, in arteries, is supported by external elastic lamina. The collagen serves to anchor the blood vessel to nearby organs, giving it stability.
The three layers of the blood vessels are: an inner tunica intima, a middle tunica media, and an outer Tunica externa.
Structure
The tunica externa is made from collagen and elastic fibers in a loose connective tissue. This is secreted by fibroblasts. This is normally the thickest tunic in veins and may be thicker than the tunica media in some larger arteries. The outer layers of the tunica externa are not distinct but rather blend with the surrounding connective tissue outside the vessel, helping to hold the vessel in relative position.
Function
The tunica externa provides basic structural support to blood vessels. It prevents vessels from expanding too much from internal blood pressure, particularly arteries. It is also relevant in controlling vascular flow in the lungs.
Clinical significance
A common pathological disorder concerning the tunica externa is scurvy, also known as vitamin C deficiency. Scurvy occurs because vitamin C is essential for the synthesis of collagen, and without it, the faulty collagen cannot maintain the vein walls and rupture, leading to a multitude of problems.
Additional images
See also
Adventitia |
https://en.wikipedia.org/wiki/Vasculum | A vasculum or a botanical box is a stiff container used by botanists to keep field samples viable for transportation. The main purpose of the vasculum is to transport plants without crushing them and by maintaining a cool, humid environment.
Construction
Vascula are cylinders typically made from tinned and sometimes lacquered iron, though wooden examples are known. The box was carried horizontally on a strap so that plant specimens lie flat and lined with moistened cloth. Traditionally, British and American vascula were somewhat flat and valise-like with a single room, while continental examples were more cylindrical and often longer, sometimes with two separate compartments. Access to the interior is through one (sometimes two) large lids in the side, allowing plants to be put in and taken out without bending or distorting them unnecessarily. This is particularly important with wildflowers, which are often fragile.
Some early 20th century specimen are made from sheet aluminium rather than tin, but otherwise follow the 19th century pattern. The exterior is usually left rough, or lacquered green.
History
The roots of the vasculum are lost in time, but may have evolved from the 17th century tin candle-box of similar construction. Linnaeus called it a vasculum dillenianum, from Latin vasculum – small container and dillenianum, referring to J.J. Dillenius, Linnaeus' friend and colleague at Oxford Botanic Garden. With rise of botany as a scientific field the mid 18th century, the vasculum became an indispensable part of the botanist's equipment.
Together with the screw-down plant press, the vasculum was popularized in Britain by naturalist William Withering around 1770. The shortened term "vasculum" appears to have become the common name applied to them around 1830. Being a hallmark of field botany, vascula were in common use until World War II . With post-war emphasis on systematics rather than alpha taxonomy and new species often collected in far-away places, field |
https://en.wikipedia.org/wiki/Institute%20of%20Physics%20and%20Engineering%20in%20Medicine | The Institute of Physics and Engineering in Medicine (IPEM) is the United Kingdom's professional body and learned society for physicists, engineers and technologists within the field of medicine, founded in 1995, changing its name from the Institution of Physics and Engineering in Medicine and Biology (IPEMB) in 1997. The Institute is governed by an elected Board of Trustees reporting to which are the Science, Research and Innovation Council and the Professional and Standards Council. The councils have operational responsibility for scientific and professional aspects of the Institute's work, respectively. Beneath the councils is a substructure of committees, groups and panels of members, which undertake the work of the Institute.
The Institute is licensed by the Engineering Council to register Chartered Engineers, Incorporated Engineers and Engineering Technologists and by the Science Council to register Chartered Scientists, Registered Scientists and Registered Science Technicians.
The aim of the Institute and its members, set out in its charitable objects and articles of association, is to promote for the public benefit the advancement of physics and engineering applied to medicine and biology, and to advance public education in the field.
History
The organization can trace its origin to three societies:
the Hospital Physicists Association (HPA) founded in 1943,
the Hospital Physics Technicians Association (HPTA) founded in 1952, and
the Biological Engineering Society (BES) founded in 1960.
The HPA created its scientific arm in 1984, the Institute of Physical Sciences in Medicine (IPSM). The trade union and scientific activities split in 1989: the scientific arm merged with the BES to form IPEMB while the trade union (HPA) joined the Manufacturing, Science and Finance Trades Union (MSF).
The Association of Medical Technologists (AMT), formerly HPTA, merged with IPEM in 2001.
Membership
There are several categories of membership:
Fellowship (FIPEM): This |
https://en.wikipedia.org/wiki/Joan%20A.%20Steitz | Joan Elaine Argetsinger Steitz (born January 26, 1941) is Sterling Professor of Molecular Biophysics and Biochemistry at Yale University and Investigator at the Howard Hughes Medical Institute. She is known for her discoveries involving RNA, including ground-breaking insights into how ribosomes interact with messenger RNA by complementary base pairing and that introns are spliced by small nuclear ribonucleic proteins (snRNPs), which occur in eukaryotes. In September 2018, Steitz won the Lasker-Koshland Award for Special Achievement in Medical Science. The Lasker award is often referred to as the 'American Nobel' because 87 of the former recipients have gone on to win Nobel prizes.
Early life and education
Steitz was born in Minneapolis, Minnesota. She grew up in Minnesota in the 1950s and 60s and attended the then all-girls Northrop Collegiate School for high school.
In 1963, Steitz received her Bachelor of Science degree in chemistry from Antioch College, Ohio, where she first became interested in molecular biology at Alex Rich's Massachusetts Institute of Technology laboratory as an Antioch "coop" intern.
After completing her undergraduate degree, Steitz applied to medical school rather than graduate school since she knew of female medical doctors but not women scientists. She was accepted to Harvard Medical School, but having been excited by a summer working as a bench scientist in the laboratory of Joseph Gall at the University of Minnesota, she declined the invitation to Harvard Medical School and instead applied to Harvard's new program in biochemistry and molecular biology. There, she was the first female graduate student to join the laboratory of Nobel Laureate James Watson, with whom she first worked on bacteriophage RNA.
Career
Steitz completed postdoctoral research at the Medical Research Council (MRC) Laboratory of Molecular Biology (LMB) at the University of Cambridge (UK), where she collaborated with Francis Crick, Sydney Brenner, and Mark Bret |
https://en.wikipedia.org/wiki/Particle%20decay | In particle physics, particle decay is the spontaneous process of one unstable subatomic particle transforming into multiple other particles. The particles created in this process (the final state) must each be less massive than the original, although the total mass of the system must be conserved. A particle is unstable if there is at least one allowed final state that it can decay into. Unstable particles will often have multiple ways of decaying, each with its own associated probability. Decays are mediated by one or several fundamental forces. The particles in the final state may themselves be unstable and subject to further decay.
The term is typically distinct from radioactive decay, in which an unstable atomic nucleus is transformed into a lighter nucleus accompanied by the emission of particles or radiation, although the two are conceptually similar and are often described using the same terminology.
Probability of survival and particle lifetime
Particle decay is a Poisson process, and hence the probability that a particle survives for time t before decaying (the survival function) is given by an exponential distribution whose time constant depends on the particle's velocity:
where
is the mean lifetime of the particle (when at rest), and
is the Lorentz factor of the particle.
Table of some elementary and composite particle lifetimes
All data are from the Particle Data Group.
{| class=wikitable style="text-align: center;"
!Type
!Name
!Symbol
!Mass (MeV)
!Mean lifetime
|-
|rowspan="3" | Lepton
|Electron / Positron
|
|0.511
|
|-
|Muon / Antimuon
|
|105.7
|
|-
|Tau lepton / Antitau
|
|1777
|
|-
|rowspan="2" | Meson
|Neutral Pion
|
|135
|
|-
|Charged Pion
|
|139.6
|
|-
|rowspan="2" | Baryon
|Proton / Antiproton
|
|938.2
|
|-
|Neutron / Antineutron
|
|939.6
|
|-
|rowspan="2" | Boson
|W boson
|
|80400
|
|-
|Z boson
|
|91000
|
|}
Decay rate
This section uses natural units, where
The lifetime of a particle is given by the inverse of its decay rate, , the |
https://en.wikipedia.org/wiki/Gastric%20pits | Gastric pits are indentations in the stomach which denote entrances to 3-5 tubular shaped gastric glands. They are deeper in the pylorus than they are in the other parts of the stomach. The human stomach has several million of these pits which dot the surface of the lining epithelium. Surface mucous cells line the pits themselves but give way to a series of other types of cells which then line the glands themselves.
Gastric acid
Gastric acid also known as gastric juice is secreted from gastric glands, which are located in gastric pits. Gastric juice contains hydrochloric acid, pepsinogen and mucus in a healthy adult. Hydrochloric acid is secreted by parietal cells, pepsinogen is secreted by gastric chief cells and mucus is secreted by mucus neck cells. |
https://en.wikipedia.org/wiki/Jane%20Coffin%20Childs%20Memorial%20Fund%20for%20Medical%20Research | The Jane Coffin Childs Memorial Fund for Medical Research (the "JCC"), established in 1937, awards the "Jane Coffin Childs Postdoctoral Fellowship" for research in the medical and related sciences bearing on cancer.
History
The Fund was founded on June 11, 1937, by Starling Winston Childs and Alice S. Childs, in memory of Jane Coffin Childs. Its funds have been on the order of $3 million.
Description
Currently, the Foundation awards 20 to 30 fellowships per year. The fellowship is regarded as one of the most prestigious fellowships in the US, and postdoctoral candidates are awarded with a three-year support. The researchers and the research labs where the fellows conduct their projects have made major scientific contributions in areas such as the advancement of understanding the human genome, and the application of genetic approaches to understanding pathway regulation, and stem cell activation. There are nearly two dozen individuals associated with the Fund—as grantees, fellows, and advisers—have won Nobel Prizes in physiology, medicine, and chemistry.
Over the years, the Fund has attracted distinguished scientists for its Board of Scientific Advisers. As of 2020, 17 of the former Board members have earned the Nobel Prize.
Members of the Board of Scientific Advisers have included:
Ali Shilatifard
Elizabeth Blackburn
Peter Cresswell
Elaine Fuchs
Tony Hunter
Cynthia Kenyon
John Kuriyan
Susan McConnell
Thomas D. Pollard
Randy Schekman
Charles J. Sherr
Pamela A. Silver
Graham C. Walker
The Jane Coffin Childs Memorial Fund for Medical Research is dedicated to providing financial support to offer highly qualified scientists the opportunity to pursue research into the causes and origins of cancer. The goal of the Fund is to provide support to the brightest individual scientists pursuing careers in cancer research while promoting and emphasizing the value and contribution of the individual in keeping with the spirit of the conception of the Fund.
Notabl |
https://en.wikipedia.org/wiki/Exfoliation%20%28botany%29 | Exfoliation (from the term "foliate", meaning “related to leaves”) means the removal or loss of leaves from a plant. It is used both to describe the loss of a leaves as a natural part of a plant's life cycle (such as in the case of deciduous trees which lose their leaves in the autumn) or because of some trauma or outside cause (such as dehydration, an infestation of caterpillars or hurricane-force winds).
In arboriculture, the term “exfoliating bark” describes the natural process and condition of the bark peeling-away from a tree trunk, typically in large pieces that remain partially attached to the trunk until such time as they are completely detached by the elements or the eventual and subsequent exfoliation of additional layers of bark. Examples of trees with exfoliating bark are the paperbark maple and various species of Plane (Sycamore) and birch.
See also
Bark peeling by deer
Plant physiology
Plant anatomy
Plant morphology |
https://en.wikipedia.org/wiki/Jan%20Bergstra | Johannes Aldert "Jan" Bergstra (born 1951) is a Dutch computer scientist. His work has focussed on logic and the theoretical foundations of software engineering, especially on formal methods for system design. He is best known as an expert on algebraic methods for the specification of data and computational processes in general.
Biography
Jan Bergstra was born in 1951 in Rotterdam, the son of Tjeerd Bergstra and Johanna Bisschop. He was educated at the Montessori Lyceum Rotterdam (gymnasium beta) and then studied mathematics at Utrecht University, starting in 1969. After an MSc he wrote a PhD thesis, defended in 1976, on recursion theory in higher types, under the supervision of Dirk van Dalen.
Bergstra held posts at the Institute of Applied Mathematics and Computer Science of the University of Leiden (1976–82), and the Centrum Wiskunde & Informatica (CWI) in Amsterdam. In 1985 he was appointed Professor of Programming and Software Engineering at the Informatics Institute of the University of Amsterdam and, at the same time, Professor of Applied Logic at Utrecht University; such split positions are not uncommon in the Netherlands. These two chairs he continues to hold.
He has been an Advisor of the CWI (1985–2004). In 1989 he worked for a year at Philips Research in Eindhoven as a project leader and, subsequently, continued as a consultant there until 2002. While at Philips he was involved in industrial projects on consumer electronics and medical equipment.
He founded CONCUR, the international conference series in Concurrency Theory, by organising the first two conferences in Amsterdam in 1990 and 1991. He is a member of several editorial boards, and is the managing editor of Science of Computer Programming and the Journal of Logic and Algebraic Programming.
In 2004 Jan Bergstra contacted Mark Burgess of the Oslo University College, looking for scientific backing for a proposed one year masters course at the University in system administration. In spite of ve |
https://en.wikipedia.org/wiki/Hilbert%20basis%20%28linear%20programming%29 | The Hilbert basis of a convex cone C is a minimal set of integer vectors such that every integer vector in C is a conical combination of the vectors in the Hilbert basis with integer coefficients.
Definition
Given a lattice and a convex polyhedral cone with generators
we consider the monoid . By Gordan's lemma, this monoid is finitely generated, i.e., there exists a finite set of lattice points such that every lattice point is an integer conical combination of these points:
The cone C is called pointed if implies . In this case there exists a unique minimal generating set of the monoid —the Hilbert basis of C. It is given by the set of irreducible lattice points: An element is called irreducible if it can not be written as the sum of two non-zero elements, i.e., implies or . |
https://en.wikipedia.org/wiki/Calvatia%20booniana | Calvatia booniana, the western giant puffball, is a puffball mushroom that can grow 10 to 70 centimetres (3.9 to 28 in) in diameter, as large as its close relative, the giant puffball of eastern North America and Europe. Like the giant puffball, it grows on composted soil such as in meadows, fields, and forests, as well as on roadsides, sagebrush flats, pastures, and other sunny places. In general, western giant puffballs occur on the west side of the Rockies and giant puffballs occur on the east side. However, on the West Coast of North America the western giant puffball is replaced by the giant puffball or a closely related species.
Its shape is round or a flattened sphere with no stalk, and it at least across when mature. The exterior is white or tan. Unlike giant puffballs, which are smooth, the western giant puffball is covered with plaques or large pointed warts. The interior is first firm and white, then yellow and slimy, and finally powdery.
Reproduction
Unlike most puffballs the western giant puffball reproduces in three stages asexually. Smaller western giant puffballs usually clump of the epididymal covering of the parent.
Cooking
The western giant puffball is edible when completely white inside. (Those that have even traces of yellow or green can cause upset stomachs.) It does not wash well, so trimming most of the dirt off is best. Washing with water makes it too soggy to saute. It is seasoned the same way as the giant puffball. It is good cubed and cooked in soup, breaded and deep-fried, steamed, sauteed, or simmered like other mushrooms. The western giant puffball, like the giant puffball, does not dehydrate well but can be cooked (to prevent it from becoming mush) and then frozen. After it thaws it should be cooked again. With the texture of tofu or marshmallows it is similar to the giant puffball. Like many other foodstuffs (and many puffballs), not all of them taste the same. |
https://en.wikipedia.org/wiki/Germline%20development | In developmental biology, the cells that give rise to the gametes are often set aside during embryonic cleavage. During development, these cells will differentiate into primordial germ cells, migrate to the location of the gonad, and form the germline of the animal.
Creation of germ plasm and primordial germ cells
Cleavage in most animals segregates cells containing germ plasm from other cells. The germ plasm effectively turns off gene expression to render the genome of the cell inert. Cells expressing germ plasm become primordial germ cells (PGCs) which will then give rise to the gametes. The germ line development in mammals, on the other hand, occurs by induction and not by an endogenous germ plasm.
Germ plasm in fruit fly
Germ plasm has been studied in detail in Drosophila. The posterior pole of the embryo contains necessary materials for the fertility of the fly. This cytoplasm, pole plasm, contains specialized materials called polar granules and the pole cells are the precursors to primordial germ cells.
Pole plasm is organized by and contains the proteins and mRNA of the posterior group genes (such as oskar, nanos gene, Tudor, vasa, and Valois). These genes play a role in germ line development to localize nanos mRNA to the posterior and localize germ cell determinants. Drosophila progeny with mutations in these genes fail to produce pole cells and are thus sterile, giving these mutations the name 'grandchildless'. The genes oskar, nanos and germ cell-less (gcl) have important roles. Oskar is sufficient to recruit the other genes to form functional germ plasm. Nanos is required to prevent mitosis and somatic differentiation and for the pole cells to migrate to function as PGCs (see next section). Gcl is necessary (but not sufficient) for pole cell formation. In addition to these genes, Pgc polar granule component blocks phosphorylation and consequently activation of RNA polymerase II and shuts down transcription.
Germ plasm in amphibians
Similar germ plasm |
https://en.wikipedia.org/wiki/Notehead | In music, a notehead is the part of a note, usually elliptical in shape, whose placement on the staff indicates the pitch, to which modifications are made that indicate duration. Noteheads may be the same shape but colored completely black or white, indicating the note value (i.e., rhythmic duration). In a whole note, the notehead, shaped differently than shorter notes, is the only component of the note. Shorter note values attach a stem to the notehead, and possibly beams or flags. The longer double whole note can be written with vertical lines surrounding it, two attached noteheads, or a rectangular notehead. An "x" shaped notehead may be used to indicate percussion, percussive effects (ghost notes), or speaking. A square, diamond, or box shaped notehead may be used to indicate a natural or artificial harmonic. A small notehead can be used to indicate a grace note.
History
Noteheads ultimately derive from the neumes used to notate Gregorian chant. The punctum, seen at right, is the simplest of the shapes and most clearly anticipates the modern notehead. When placed on a clef, the position of a notehead indicates the relative pitch of a note. The development of different colors of noteheads, and the use of it to indicate rhythmic values, was the use of white mensural notation, adopted around 1450.
Franco of Cologne, ancient composer and music theorist, codified a system of rhythm notation. He explained this system in his work, Ars Cantus Mensurabilis (“The Art of Measurable Music”), circa 1280. In this system, the relative duration of notes was indicated by the note shapes. The noteheads were rectangles, squares, or diamonds depending on the note length. This system was expanded during the Ars Nova period.
Shortly before the Renaissance, scribes began to write the notes of the Franconian and Ars Nova style with open noteheads. During the Renaissance, composers added shorter note durations that used filled-in noteheads. Near the end of the 16th century, the sq |
https://en.wikipedia.org/wiki/World%20Geographical%20Scheme%20for%20Recording%20Plant%20Distributions | The World Geographical Scheme for Recording Plant Distributions (WGSRPD) is a biogeographical system developed by the international Biodiversity Information Standards (TDWG) organization, formerly the International Working Group on Taxonomic Databases. The WGSRPD standards, like other standards for data fields in botanical databases, were developed to promote "the wider and more effective dissemination of information about the world's heritage of biological organisms for the benefit of the world at large". The system provides clear definitions and codes for recording plant distributions at four scales or levels, from "botanical continents" down to parts of large countries. The codes may be referred to as TDWG geographical codes. Current users of the system include the International Union for Conservation of Nature (IUCN), the Germplasm Resources Information Network (GRIN), and Plants of the World Online (POWO).
Principles of organization
The scheme is one of a number developed by Biodiversity Information Standards particularly aimed at taxonomic databases. The starting point was the "need for an agreed system of geographical units at approximately 'country' level and upwards for use in recording plant distributions". The scheme represents a compromise between political and botanical divisions. All boundaries either follow a political boundary (country boundary, province boundary, etc.), or coastlines. The scheme also aims to follow botanical tradition, in terms of the distribution categories used in works like the Flora Europaea, Flora Malesiana, or Med-Checklist. This approach occasionally leads to departures from political boundaries. Thus the scheme follows Flora Europaea in placing the eastern Aegean islands (such as Lesbos, Samos and Rhodes) in the West Asia region, rather than in Europe where they belong politically as part of Greece.
Levels
The scheme defines geographic places at four scales or levels, from "botanical continents" down to parts of large c |
https://en.wikipedia.org/wiki/Network%20segmentation | Network segmentation in computer networking is the act or practice of splitting a computer network into subnetworks, each being a network segment. Advantages of such splitting are primarily for boosting performance and improving security.
Advantages
Reduced congestion: On a segmented network, there are fewer hosts per subnetwork and the traffic and thus congestion per segment is reduced
Improved security:
Broadcasts will be contained to local network. Internal network structure will not be visible from outside.
There is a reduced attack surface available to pivot in if one of the hosts on the network segment is compromised. Common attack vectors such as LLMNR and NetBIOS poisoning can be partially alleviated by proper network segmentation as they only work on the local network. For this reason it is recommended to segment the various areas of a network by usage. A basic example would be to split up web servers, databases servers and standard user machines each into their own segment.
By creating network segments containing only the resources specific to the consumers that you authorise access to, you are creating an environment of least privilege
Containing network problems: Limiting the effect of local failures on other parts of network
Controlling visitor access: Visitor access to the network can be controlled by implementing VLANs to segregate the network
Improved security
When a cyber-criminal gains unauthorized access to a network, segmentation or “zoning” can provide effective controls to limit further movement across the network. PCI-DSS (Payment Card Industry Data Security Standard), and similar standards, provide guidance on creating clear separation of data within the network, for example separating the network for Payment Card authorizations from those for Point-of-Service (till) or customer wi-fi traffic. A sound security policy entails segmenting the network into multiple zones, with varying security requirements, and rigorously enforcing th |
https://en.wikipedia.org/wiki/Subserosa | The subserosa or tela subserosa, is a thin layer of tissue in the walls of various organs. It is a layer of connective tissue (usually of the areolar type) between the muscular layer (muscularis externa) and the serosa (serous membrane).
The subserosa has clinical importance particularly in cancer staging (for example, in staging stomach cancer or uterine cancer).
The subserosa (sub- + serosa) is to a serous membrane what the submucosa (sub- + mucosa) is to a mucous membrane. |
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