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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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Xlib
Xlib (also known as libX11) is an X Window System protocol client library written in the C programming language. It contains functions for interacting with an X server. These functions allow programmers to write programs without knowing the details of the X protocol. Few applications use Xlib directly; rather, they employ other libraries that use Xlib functions to provide widget toolkits: Xlib appeared around 1985, and is used in GUIs for many Unix-like operating systems. A re-implementation of Xlib was introduced in 2007 using XCB.
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  • 24 Oct 2022
Topic Review
Shallow Affect
Reduced affect display, sometimes referred to as emotional blunting, is a condition of reduced emotional reactivity in an individual. It manifests as a failure to express feelings (affect display) either verbally or nonverbally, especially when talking about issues that would normally be expected to engage the emotions. Expressive gestures are rare and there is little animation in facial expression or vocal inflection. Reduced affect can be symptomatic of autism, schizophrenia, depression, posttraumatic stress disorder, depersonalization disorder, schizoid personality disorder or brain damage. It may also be a side effect of certain medications (e.g., antipsychotics and antidepressants). Reduced affect should be distinguished from apathy and anhedonia, which explicitly refer to a lack of emotion, whereas reduced affect is a lack of emotional expression (affect display) regardless of whether emotion (underlying affect) is actually reduced or not.
  • 12.7K
  • 24 Oct 2022
Topic Review
Medical Uses of Silver
The medical uses of silver include its use in wound dressings, creams, and as an antibiotic coating on medical devices. Wound dressings containing silver sulfadiazine or silver nanomaterials may be used to treat external infections. The limited evidence available shows that silver coatings on endotracheal breathing tubes may reduce the incidence of ventilator-associated pneumonia. There is tentative evidence that using silver-alloy indwelling catheters for short-term catheterizing will reduce the risk of catheter-acquired urinary tract infections. Silver generally has low toxicity, and minimal risk is expected when silver is used in approved medical applications. Alternative medicine products such as colloidal silver are not safe or effective.
  • 2.5K
  • 24 Oct 2022
Topic Review
Sound Masking
Masking Sound is the addition of generated sound (commonly, though inaccurately, referred to as "white noise" or "pink noise") into an environment to mask unwanted sound. It relies on auditory masking. Masking sound is not an active noise control (noise cancellation technique). Masking sound reduces or eliminates perception of sound. The technology is promoted as a widespread application to an entire area to improve the acoustical satisfaction, by improving the acoustical privacy of the space. This improves one's ability to focus and their productivity. Masking sound is analogous to light. - Sound Power and Luminosity - Sound Intensity and Light intensity - They both have spectral characteristics.
  • 875
  • 24 Oct 2022
Topic Review
Mineral Processing
In the field of extractive metallurgy, mineral processing, also known as ore dressing, is the process of separating commercially valuable minerals from their ores.
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  • 27 Oct 2022
Topic Review
Space Shuttle Main Engine
The Aerojet Rocketdyne RS-25, otherwise known as the Space Shuttle main engine (SSME), is a liquid-fuel cryogenic rocket engine that was used on NASA's Space Shuttle and is planned to be used on its successor, the Space Launch System. Designed and manufactured in the United States by Rocketdyne (later known as Pratt & Whitney Rocketdyne and Aerojet Rocketdyne), the RS-25 burns cryogenic liquid hydrogen and liquid oxygen propellants, with each engine producing 1,859 kN (418,000 lbf) of thrust at liftoff. Although the RS-25 can trace its heritage back to the 1960s, concerted development of the engine began in the 1970s, with the first flight, STS-1, occurring on April 12, 1981. The RS-25 has undergone several upgrades over its operational history to improve the engine's reliability, safety, and maintenance load. Subsequently, the RS-25D is the most efficient liquid fuel rocket engine currently in use. The engine produces a specific impulse (Isp) of 452 seconds (4.43 km/s) in a vacuum, or 366 seconds (3.59 km/s) at sea level, has a mass of approximately 3.5 tonnes (7,700 pounds), and is capable of throttling between 67% and 109% of its rated power level in one-percent increments. The RS-25 operates at temperatures ranging from −253 °C (−423 °F) to 3300 °C (6000 °F). The Space Shuttle used a cluster of three RS-25 engines mounted in the stern structure of the orbiter, with fuel being drawn from the external tank. The engines were used for propulsion during the entirety of the spacecraft's ascent, with additional thrust being provided by two solid rocket boosters and the orbiter's two AJ-10 orbital maneuvering system engines. Following each flight, the RS-25 engines were removed from the orbiter, inspected, and refurbished before being reused on another mission.
  • 11.9K
  • 24 Oct 2022
Topic Review
Intrastate Airline
Intrastate airlines in the U.S. are defined as air carriers operating inside of one individual state and thus not flying across state lines. Larger intrastate airlines in the U.S. that operated mainline turboprop and/or jet aircraft were created as a result of past federal airline regulations as passenger air carriers that only flew intrastate service were not regulated by the federal government but were instead primarily regulated by the respective state governments in their home states. For example, Pacific Southwest Airlines (PSA) and Air California were both regulated by the California Public Utilities Commission (CPUC) prior to the federal Airline Deregulation Act of 1978. Intrastate air carriers primarily operated in the United States but also elsewhere globally. In the U.S., California, Florida, Hawaii and Texas had scheduled jet passenger service operated by intrastate air carriers in the past.
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  • 24 Oct 2022
Topic Review
Cheating
Cheating is a term used in behavioral ecology and ethology to describe behavior whereby organisms receive a benefit at the cost of other organisms. Cheating is common in many mutualistic and altruistic relationships. A cheater is an individual who does not cooperate (or cooperates less than their fair share) but can potentially gain the benefit from others cooperating. Cheaters are also those who selfishly use common resources to maximize their individual fitness at the expense of a group. Natural selection favors cheating, but there are mechanisms to regulate it.
  • 1.3K
  • 27 Oct 2022
Topic Review
Anaxagoras
Anaxagoras (/ˌænækˈsæɡərəs/; Greek: Ἀναξαγόρας, Anaxagoras, "lord of the assembly"; c. 500 – c. 428 BC) was a Pre-Socratic Greek philosopher. Born in Clazomenae at a time when Asia Minor was under the control of the Persian Empire, Anaxagoras came to Athens. According to Diogenes Laërtius and Plutarch, in later life he was charged with impiety and went into exile in Lampsacus; the charges may have been political, owing to his association with Pericles, if they were not fabricated by later ancient biographers. Responding to the claims of Parmenides on the impossibility of change, Anaxagoras described the world as a mixture of primary imperishable ingredients, where material variation was never caused by an absolute presence of a particular ingredient, but rather by its relative preponderance over the other ingredients; in his words, "each one is... most manifestly those things of which there are the most in it". He introduced the concept of Nous (Cosmic Mind) as an ordering force, which moved and separated out the original mixture, which was homogeneous, or nearly so. He also gave a number of novel scientific accounts of natural phenomena. He deduced a correct explanation for eclipses and described the Sun as a fiery mass larger than the Peloponnese, as well as attempting to explain rainbows and meteors.
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  • 24 Oct 2022
Topic Review
Vaginal Anomalies
Vaginal anomalies are abnormal structures that are formed (or not formed) during the prenatal development of the female reproductive system and are rare congenital defects that result in an abnormal or absent vagina. When present, they are often found with uterine, skeletal and urinary abnormalities. This is because these structures, like the vagina, are most susceptible to disruption during crucial times of organ-genesis. Many of these defects are classified under the broader term Müllerian duct anomalies. Müllerian duct anomalies are caused by a disturbance during the embryonic time of genitourinary development. The other isolated incidents of vaginal anomalies can occur with no apparent cause. Oftentimes vaginal anomalies are part of a cluster of defects or syndromes. In addition, inheritance can play a part as can prenatal exposure to some teratogens. Many vaginal anomalies are not detected at birth because the external genitalia appear to be normal. Other organs of the reproductive system may not be affected by an abnormality of the vagina. The uterus, fallopian tubes and ovaries can be functional despite the presence of a defect of the vagina and external genitalia. A vaginal anomaly may not affect fertility. Though it depends on the extent of the vaginal defect, it is possible for conception to occur. In instances where a functional ovary exists, IVF may be successful. Functioning ovaries in a woman with a vaginal defect allows the implantation of a fertilized ovum into the uterus of an unaffected gestational carrier, usually another human. A successful conception and can occur. Vaginal length varies from 6.5 to 12.5 cm. Since this is slightly shorter than older descriptions, it may impact the diagnosis of women with vaginal agenesis or hypoplasia who may unnecessarily be encouraged to undergo treatment to increase the size of the vagina. Vaginal anomalies may cause difficulties in urination, conception, pregnancy, impair sex. Psychosocial effects can also exist.
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  • 24 Oct 2022
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