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HandWiki is the world's largest wiki-style encyclopedia dedicated to science, technology and computing. It allows you to create and edit articles as long as you have external citations and login account. In addition, this is a content management environment that can be used for collaborative editing of original scholarly content, such as books, manuals, monographs and tutorials.

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Gag Order
A gag order (also known as a gagging order or suppression order) is an order, typically a legal order by a court or government, restricting information or comment from being made public or passed onto any unauthorized third party. The phrase may sometimes be used of a private order by an employer or other institution. Gag orders may be used, for example, to keep legitimate trade secrets of a company, to protect the integrity of ongoing police or military operations, or to protect the privacy of victims or minors. Conversely, as their downside, they may be abused as a useful tool for those of financial means to intimidate witnesses and prevent release of information, using the legal system rather than other methods of intimidation. Strategic Lawsuit Against Public Participation (SLAPP) orders may potentially be abused in this way. Gag orders are sometimes used in an attempt to assure a fair trial by preventing prejudicial pre-trial publicity, although their use for this purpose is controversial since they are a potentially unconstitutional prior restraint that can lead to the press's using less reliable sources such as off-the-record statements and second- or third-hand accounts. In a similar manner, a "gag law" may limit freedom of the press, by instituting censorship or restricting access to information.
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  • 17 Oct 2022
Topic Review
Exclusion of the Null Hypothesis
In inferential statistics, the null hypothesis (often denoted H0) is a default hypothesis that a quantity to be measured is zero (null). Typically, the quantity to be measured is the difference between two situations, for instance to try to determine if there is a positive proof that an effect has occurred or that samples derive from different batches. The null hypothesis is effectively stating that a quantity (of interest) is larger or equal to zero AND smaller or equal to zero. If either requirement can be positively overturned, the null hypothesis is "excluded from the realm of possibilities". The null hypothesis is generally assumed to remain possibly true. Multiple analyses can be performed to show how the hypothesis should be either: rejected or excluded e.g. having high confidence level, thus demonstrating a statistically significant difference. This is demonstrated by showing that zero is outside of the specified confidence interval of the measurement on either side, typically within the real numbers. Failure to exclude the null hypothesis (with any confidence) does logically NOT confirm or support the (unprovable) null hypothesis. (When you have not proven something is e.g. bigger than x, it does not necessarily mean you have made it plausible that it is smaller or equal than x; alternatively you may just have done a lousy measurement with low accuracy. Confirming the null hypothesis two-sided would amount to positively proving it is bigger or equal than 0 AND to positively proving it is smaller or equal than 0; this is something for which you need infinite accuracy as well as exactly zero effect neither of which normally are realistic. Also measurements will never indicate a non-zero probability of exactly zero difference.) So failure of an exclusion of a null hypothesis amounts to a "don't know" at the specified confidence level; it does not immediately imply null somehow, as the data may already show a (less strong) indication for a non-null. The used confidence level does absolutely certainly not correspond to the likelihood of null at failing to exclude; in fact in this case a high used confidence level expands the still plausible range. A non-null hypothesis can have the following meanings, depending on the author a) a value other than zero is used, b) some margin other than zero is used and c) the "alternative" hypothesis. Testing (excluding or failing to exclude) the null hypothesis provides evidence that there are (or are not) statistically sufficient grounds to believe there is a relationship between two phenomena (e.g., that a potential treatment has a non-zero effect, either way). Testing the null hypothesis is a central task in statistical hypothesis testing in the modern practice of science. There are precise criteria for excluding or not excluding a null hypothesis at a certain confidence level. The confidence level should indicate the likelihood that much more and better data would still be able to exclude the null hypothesis on the same side. The concept of a null hypothesis is used differently in two approaches to statistical inference. In the significance testing approach of Ronald Fisher, a null hypothesis is rejected if the observed data is significantly unlikely to have occurred if the null hypothesis were true. In this case, the null hypothesis is rejected and an alternative hypothesis is accepted in its place. If the data is consistent with the null hypothesis statistically possibly true, then the null hypothesis is not rejected. In neither case is the null hypothesis or its alternative proven; with better or more data, the null may still be rejected. This is analogous to the legal principle of presumption of innocence, in which a suspect or defendant is assumed to be innocent (null is not rejected) until proven guilty (null is rejected) beyond a reasonable doubt (to a statistically significant degree). In the hypothesis testing approach of Jerzy Neyman and Egon Pearson, a null hypothesis is contrasted with an alternative hypothesis, and the two hypotheses are distinguished on the basis of data, with certain error rates. It is used in formulating answers in research. Statistical inference can be done without a null hypothesis, by specifying a statistical model corresponding to each candidate hypothesis, and by using model selection techniques to choose the most appropriate model. (The most common selection techniques are based on either Akaike information criterion or Bayes factor).
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  • 17 Oct 2022
Topic Review
Celebrity Worship Syndrome
Celebrity worship syndrome (CWS) is an obsessive addictive disorder in which a person becomes overly involved with the details of a celebrity's personal and professional life. Psychologists have indicated that though many people obsess over film, television, sport and pop stars, the only common factor between them is that they are all figures in the public eye. Written observations of celebrity worship date back to the 19th century.
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  • 17 Oct 2022
Topic Review
Net Neutrality (Last Week Tonight)
"Net Neutrality" is the first segment of the HBO news satire television series Last Week Tonight with John Oliver devoted to net neutrality in the United States. It aired for 13 minutes on June 1, 2014, as part of the fifth episode of Last Week Tonight's first season. During this segment, as well Oliver's follow-up segment entitled "Net Neutrality II", comedian John Oliver discusses the threats to net neutrality. Under the administration of President Barack Obama, the Federal Communications Commission (FCC) was considering two options for net neutrality in early 2014. The FCC proposed permitting fast and slow broadband lanes, which would compromise net neutrality, but was also considering reclassifying broadband as a telecommunication service, which would preserve net neutrality. After a surge of comments supporting net neutrality that were inspired by Oliver's episode, the FCC voted to reclassify broadband as a utility in 2015.
  • 1.1K
  • 17 Oct 2022
Topic Review
SpaceX Rocket Engines
Since the founding of SpaceX in 2002, the company has developed four families of rocket engines — Merlin, Kestrel, Draco and SuperDraco — and is currently developing another rocket engine: Raptor.
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  • 17 Oct 2022
Topic Review
Chrysler Pacifica (RU)
The Chrysler Pacifica is a minivan being produced by the Chrysler division of FCA US LLC. Despite sharing its name with a discontinued crossover, it is an all-new design replacing the Chrysler Town & Country. The minivan is produced with two powertrains, a 3.6-liter gasoline powered engine and a plug-in hybrid, marketed as Pacifica Hybrid. The plug-in hybrid version has a 16-kWh lithium-ion battery that can propel the car up to 33 mi (53 km) on electric power alone. The gasoline-only version of the Pacifica minivan went on sale in mid-2016, while the plug-in hybrid version became available in early 2017.
  • 2.7K
  • 17 Oct 2022
Topic Review
Hypoxemia
Hypoxemia is an abnormally low level of oxygen in the blood. More specifically, it is oxygen deficiency in arterial blood. Hypoxemia has many causes, and often causes hypoxia as the blood is not supplying enough oxygen to the tissues of the body.
  • 1.1K
  • 17 Oct 2022
Topic Review
Biological Patent
A biological patent is a patent on an invention in the field of biology that by law allows the patent holder to exclude others from making, using, selling, or importing the protected invention for a limited period of time. The scope and reach of biological patents vary among jurisdictions, and may include biological technology and products, genetically modified organisms and genetic material. The applicability of patents to substances and processes wholly or partially natural in origin is a subject of debate.
  • 1.9K
  • 17 Oct 2022
Topic Review
2001 Massacre of Plaza de Mayo
The 2001 Massacre of Plaza de Mayo was a slaughter of people at Plaza de Mayo (May Square), Buenos Aires, Argentina, and around this area that took place on December 20, 2001. Five people were murdered. The names of the fatal victims were: Carlos Almiron, Gustavo Ariel Benedetto, Diego Lamagna, Alberto Marquez and Gaston Marcelo Riva. The perpetrators tried to kill four more people (Marcelo Dorado, Martin Galli, Sergio Ruben Sanchez, and Paula Simonetti), but they did not succeed. A total of 277 injuries was reported.These crimes were committed under Fernando de la Rua’s presidential term in which Argentina was suffering one of its deepest crises and people were rioting in different cities around the nation. These incidents left a total of 39 people that were murdered across the country, among them 7 children.The trial against the 17 defendants started on February 24, 2014.
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  • 17 Oct 2022
Topic Review
Interconnects (Integrated Circuits)
In integrated circuits (ICs), interconnects are structures that connect two or more circuit elements (such as transistors) together electrically. The design and layout of interconnects on an IC is vital to its proper function, performance, power efficiency, reliability, and fabrication yield. The material interconnects are made from depends on many factors. Chemical and mechanical compatibility with the semiconductor substrate, and the dielectric in between the levels of interconnect is necessary, otherwise barrier layers are needed. Suitability for fabrication is also required; some chemistries and processes prevent integration of materials and unit processes into a larger technology (recipe) for IC fabrication. In fabrication, interconnects are formed during the back-end-of-line after the fabrication of the transistors on the substrate. Interconnects are classified as local or global interconnects depending on the signal propagation distance it is able to support. The width and thickness of the interconnect, as well as the material from which it is made, are some of the significant factors that determine the distance a signal may propagate. Local interconnects connect circuit elements that are very close together, such as transistors separated by ten or so other contiguously laid out transistors. Global interconnects can transmit further, such as over large-area sub-circuits. Consequently, local interconnects may be formed from materials with relatively high electrical resistivity such as polycrystalline silicon (sometimes silicided to extend its range) or tungsten. To extend the distance an interconnect may reach, various circuits such as buffers or restorers may be inserted at various points along a long interconnect.
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  • 17 Oct 2022
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