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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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SODAR
SODAR (SOnic Detection And Ranging), also written as sodar, is a meteorological instrument used as a wind profiler to measure the scattering of sound waves by atmospheric turbulence. SODAR systems are used to measure wind speed at various heights above the ground, and the thermodynamic structure of the lower layer of the atmosphere. Sodar systems are in fact nothing more than sonar systems used in the air rather than in water; more specifically, since they operate using the Doppler effect with a multi-beam configuration to determine wind speed, they are the exact in-air equivalent to a subclass of sonar systems known as acoustic Doppler current profilers. Other names used for sodar systems include sounder, echosounder and acoustic radar.
  • 1.1K
  • 29 Sep 2022
Topic Review
Tuberculin
Tuberculin, also known as purified protein derivative, is a combination of proteins that are used in the diagnosis of tuberculosis. This use is referred to as the tuberculin skin test and is recommended only for those at high risk. Reliable administration of the skin test requires large amounts of training, supervision, and practice. Injection is done into the skin. After 48 to 72 hours, if there is more than a five to ten millimeter area of swelling, the test is considered positive. Common side effects include redness, itchiness, and pain at the site of injection. Allergic reactions may occasionally occur. The test may be falsely positive in those who have been previously vaccinated with BCG or have been infected by other types of mycobacteria. The test may be falsely negative within ten weeks of infection, in those less than six months old, and in those who have been infected for many years. Use is safe in pregnancy. Tuberculin was discovered in 1890 by Robert Koch. Koch, best known for his work on the etiology of tuberculosis (TB), laid down various rigorous guidelines that aided the establishment between a pathogen and the specific disease that followed that were later named Koch's postulates. Although he initially believed it would cure tuberculosis, this was later disproved. Tuberculin is made from an extract of Mycobacterium tuberculosis. It is on the World Health Organization's List of Essential Medicines.
  • 1.6K
  • 29 Sep 2022
Topic Review
Inertial Confinement Fusion
Inertial confinement fusion (ICF) is a type of fusion energy research that attempts to initiate nuclear fusion reactions by heating and compressing a fuel target, typically in the form of a pellet that most often contains a mixture of deuterium and tritium. Typical fuel pellets are about the size of a pinhead and contain around 10 milligrams of fuel. To compress and heat the fuel, energy is delivered to the outer layer of the target using high-energy beams of laser light, electrons or ions, although for a variety of reasons, almost all ICF devices (As of 2015) have used lasers. The heated outer layer explodes outward, producing a reaction force against the remainder of the target, accelerating it inwards, compressing the target. This process is designed to create shock waves that travel inward through the target. A sufficiently powerful set of shock waves can compress and heat the fuel at the center so much that fusion reactions occur. ICF is one of two major branches of fusion energy research, the other being magnetic confinement fusion. When it was first proposed in the early 1970s, ICF appeared to be a practical approach to power production and the field flourished. Experiments during the 1970s and '80s demonstrated that the efficiency of these devices was much lower than expected, and reaching ignition would not be easy. Throughout the 1980s and '90s, many experiments were conducted in order to understand the complex interaction of high-intensity laser light and plasma. These led to the design of newer machines, much larger, that would finally reach ignition energies. The largest operational ICF experiment is the National Ignition Facility (NIF) in the US, designed using the decades-long experience of earlier experiments. Like those earlier experiments, however, NIF has failed to reach ignition and is, as of 2015, generating about ​1⁄3 of the required energy levels.
  • 4.0K
  • 29 Sep 2022
Topic Review
History of Biotechnology
Biotechnology is the application of scientific and engineering principles to the processing of materials by biological agents to provide goods and services. From its inception, biotechnology has maintained a close relationship with society. Although now most often associated with the development of drugs, historically biotechnology has been principally associated with food, addressing such issues as malnutrition and famine. The history of biotechnology begins with zymotechnology, which commenced with a focus on brewing techniques for beer. By World War I, however, zymotechnology would expand to tackle larger industrial issues, and the potential of industrial fermentation gave rise to biotechnology. However, both the single-cell protein and gasohol projects failed to progress due to varying issues including public resistance, a changing economic scene, and shifts in political power. Yet the formation of a new field, genetic engineering, would soon bring biotechnology to the forefront of science in society, and the intimate relationship between the scientific community, the public, and the government would ensue. These debates gained exposure in 1975 at the Asilomar Conference, where Joshua Lederberg was the most outspoken supporter for this emerging field in biotechnology. By as early as 1978, with the development of synthetic human insulin, Lederberg's claims would prove valid, and the biotechnology industry grew rapidly. Each new scientific advance became a media event designed to capture public support, and by the 1980s, biotechnology grew into a promising real industry. In 1988, only five proteins from genetically engineered cells had been approved as drugs by the United States Food and Drug Administration (FDA), but this number would skyrocket to over 125 by the end of the 1990s. The field of genetic engineering remains a heated topic of discussion in today's society with the advent of gene therapy, stem cell research, cloning, and genetically modified food. While it seems only natural nowadays to link pharmaceutical drugs as solutions to health and societal problems, this relationship of biotechnology serving social needs began centuries ago.
  • 2.8K
  • 21 Apr 2023
Topic Review
2015–16 Zika Virus Epidemic
In early 2015, a widespread epidemic of Zika fever, caused by the Zika virus in Brazil , spread to other parts of South and North America. It also affected several islands in the Pacific, and Southeast Asia. In January 2016, the World Health Organization (WHO) said the virus was likely to spread throughout most of the Americas by the end of the year. In November 2016 WHO announced the end of the Zika epidemic. In February 2016, WHO declared the outbreak a Public Health Emergency of International Concern as evidence grew that Zika can cause birth defects as well as neurological problems. The virus can be transmitted from an infected pregnant woman to her fetus, then can cause microcephaly and other severe brain anomalies in the infant. Zika infections in adults can result in Guillain–Barré syndrome. Prior to this outbreak, Zika was considered a mild infection, as most Zika virus infections are asymptomatic, making it difficult to determine precise estimates of the number of cases. In approximately one in five cases, Zika virus infections result in Zika fever, a minor illness that causes symptoms such as fever and a rash. The virus is spread mainly by the Aedes aegypti mosquito, which is commonly found throughout the tropical and subtropical Americas. It can also be spread by the Aedes albopictus ("Asian tiger") mosquito, which is distributed as far north as the Great Lakes region in North America. Men infected with Zika can transmit the virus to their sexual partners. A number of countries have issued travel warnings, and the outbreak is expected to reduce tourism significantly. Several countries have taken the unusual step of advising their citizens to delay pregnancy until more is known about the virus and its impact on fetal development. Furthermore, the outbreak raised concerns regarding the safety of athletes and spectators at the 2016 Summer Olympics in Rio de Janeiro. In Brazil, the Zika virus epidemic revealed structural problems of the health system, in particular in public health services and basic sanitation.
  • 2.3K
  • 29 Sep 2022
Topic Review
Deformation
In physics, deformation is the continuum mechanics transformation of a body from a reference configuration to a current configuration. A configuration is a set containing the positions of all particles of the body. A deformation can occur because of external loads, intrinsic activity (e.g. muscle contraction), body forces (such as gravity or electromagnetic forces), or changes in temperature, moisture content, or chemical reactions, etc. Strain is related to deformation in terms of relative displacement of particles in the body that excludes rigid-body motions. Different equivalent choices may be made for the expression of a strain field depending on whether it is defined with respect to the initial or the final configuration of the body and on whether the metric tensor or its dual is considered. In a continuous body, a deformation field results from a stress field due to applied forces or because of some changes in the temperature field of the body. The relation between stress and strain is expressed by constitutive equations, e.g., Hooke's law for linear elastic materials. Deformations which cease to exist after the stress field is removed are termed as elastic deformation. In this case, the continuum completely recovers its original configuration. On the other hand, irreversible deformations remain. They exist even after stresses have been removed. One type of irreversible deformation is plastic deformation, which occurs in material bodies after stresses have attained a certain threshold value known as the elastic limit or yield stress, and are the result of slip, or dislocation mechanisms at the atomic level. Another type of irreversible deformation is viscous deformation, which is the irreversible part of viscoelastic deformation. In the case of elastic deformations, the response function linking strain to the deforming stress is the compliance tensor of the material.
  • 4.9K
  • 09 Oct 2022
Topic Review
Coherence Therapy
Coherence therapy is a system of psychotherapy based in the theory that symptoms of mood, thought and behavior are produced coherently according to the person's current mental models of reality, most of which are implicit and unconscious. It was founded by Bruce Ecker and Laurel Hulley in the 1990s. It has been considered among the most well respected postmodern/constructivist therapies.
  • 1.5K
  • 29 Sep 2022
Topic Review
Information Technology Audit
An information technology audit, or information systems audit, is an examination of the management controls within an Information technology (IT) infrastructure and business applications. The evaluation of evidence obtained determines if the information systems are safeguarding assets, maintaining data integrity, and operating effectively to achieve the organization's goals or objectives. These reviews may be performed in conjunction with a financial statement audit, internal audit, or other form of attestation engagement. IT audits are also known as automated data processing audits (ADP audits) and computer audits. They were formerly called electronic data processing audits (EDP audits).
  • 992
  • 29 Sep 2022
Topic Review
Wani (Scholar)
Wani (Japanese: 王仁, 和邇吉師, romanized: Wani, Wani Kishi) is a semi-legendary scholar who is said to have been sent to Japan by Baekje of southwestern Korea during the reign of Emperor Ōjin. He used to be associated with the introduction of the Chinese writing system to Japan.
  • 2.1K
  • 29 Sep 2022
Topic Review
Weekday Cartoon
A weekday cartoon is the colloquial term for the animated series programming that was typically scheduled on weekday mornings and afternoons in the United States on many major television networks and in broadcast syndication since the 1960s.
  • 1.1K
  • 29 Sep 2022
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