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Whole-body Counting
In health physics, whole-body counting refers to the measurement of radioactivity ''within'' the human body. The technique is primarily applicable to radioactive material that emits gamma rays. Alpha particle decays can also be detected indirectly by their coincident gamma radiation. In certain circumstances, beta emitters can be measured, but with degraded sensitivity. The instrument used is normally referred to as a whole body counter. This must not be confused with a "whole body monitor" which used for personnel exit monitoring, which is the term used in radiation protection for checking for external contamination of a whole body of a person leaving a radioactive contamination controlled area. Principles If a gamma ray is emitted from a radioactive element within the human body due to radioactive decay, and its energy is sufficient to escape then it can be detected. This would be by means of either a scintillation detector or a semiconductor detector placed in close proximi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Health Physics
Health physics, also referred to as the science of radiation protection, is the profession devoted to protecting people and their environment from potential radiation hazards, while making it possible to enjoy the beneficial uses of radiation. Health physicists normally require a four-year bachelor’s degree and qualifying experience that demonstrates a professional knowledge of the theory and application of radiation protection principles and closely related sciencesHealth physicistsprincipally work at facilities where radionuclides or other sources of ionizing radiation (such as X-ray generators) are used or produced; these include research, industry, education, medical facilities, nuclear power, military, environmental protection, enforcement of government regulations, and decontamination and decommissioning—the combination of education and experience for health physicists depends on the specific field in which the health physicist is engaged. Sub Specialties There are many ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Urinalysis
Urinalysis, a portmanteau of the words ''urine'' and ''analysis'', is a panel of medical tests that includes physical (macroscopic) examination of the urine, chemical evaluation using urine test strips, and microscopic examination. Macroscopic examination targets parameters such as color, clarity, odor, and specific gravity; urine test strips measure chemical properties such as pH, glucose concentration, and protein levels; and microscopy is performed to identify elements such as cells, urinary casts, crystals, and organisms. Background Urine is produced by the filtration of blood in the kidneys. The formation of urine takes place in microscopic structures called nephrons, about one million of which are found in a normal human kidney. Blood enters the kidney though the renal artery and flows through the kidney's vasculature into the Glomerulus (kidney), glomerulus, a tangled knot of capillaries surrounded by Bowman's capsule. The glomerulus and Bowman's capsule together form t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radiation Health Effects
In physics, radiation is the emission or transmission of energy in the form of waves or particles through space or through a material medium. This includes: * ''electromagnetic radiation'', such as radio waves, microwaves, infrared, visible light, ultraviolet, x-rays, and Gamma ray, gamma radiation (γ) * ''particle radiation'', such as alpha radiation, alpha radiation (α), beta radiation, beta radiation (β), proton radiation and neutron radiation (particles of non-zero rest energy) * ''acoustics, acoustic radiation'', such as ultrasound, sound, and seismic waves (dependent on a physical transmission medium) * ''gravitational wave, gravitational radiation'', that takes the form of gravitational waves, or ripples in the curvature of spacetime Radiation is often categorized as either ''ionizing radiation, ionizing'' or ''non-ionizing radiation, non-ionizing'' depending on the energy of the radiated particles. Ionizing radiation carries more than 10 electron volt, eV, which ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
University Of Chicago
The University of Chicago (UChicago, Chicago, U of C, or UChi) is a private research university in Chicago, Illinois. Its main campus is located in Chicago's Hyde Park neighborhood. The University of Chicago is consistently ranked among the best universities in the world and it is among the most selective in the United States. The university is composed of an undergraduate college and five graduate research divisions, which contain all of the university's graduate programs and interdisciplinary committees. Chicago has eight professional schools: the Law School, the Booth School of Business, the Pritzker School of Medicine, the Crown Family School of Social Work, Policy, and Practice, the Harris School of Public Policy, the Divinity School, the Graham School of Continuing Liberal and Professional Studies, and the Pritzker School of Molecular Engineering. The university has additional campuses and centers in London, Paris, Beijing, Delhi, and Hong Kong, as well as in downtown ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Leonidas D
Leonidas I (; grc-gre, Λεωνίδας; died 19 September 480 BC) was a king of the Greek city-state of Sparta, and the 17th of the Agiad line, a dynasty which claimed descent from the mythological demigod Heracles. Leonidas I was son of King Anaxandridas II. He succeeded his half-brother King Cleomenes I to the throne in c. 489 BC. His co-ruler was King Leotychidas. He was succeeded by his son, King Pleistarchus. Leonidas had a notable participation in the Second Greco-Persian War, where he led the allied Greek forces to a last stand at the Battle of Thermopylae (480 BC) while attempting to defend the pass from the invading Persian army; he died at the battle and entered myth as the leader of the 300 Spartans. While the Greeks lost this battle, they were able to expel the Persian invaders in the following year. Life According to Herodotus, Leonidas' mother was not only his father's wife but also his father's niece and had been barren for so long that the ephors, the five an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Detection Limit
The limit of detection (LOD or LoD) is the lowest signal, or the lowest corresponding quantity to be determined (or extracted) from the signal, that can be observed with a sufficient degree of confidence or statistical significance. However, the exact threshold (level of decision) used to decide when a signal significantly emerges above the continuously fluctuating background noise remains arbitrary and is a matter of policy and often of debate among scientists, statisticians and regulators depending on the stakes in different fields. Significance in analytical chemistry In analytical chemistry, the detection limit, lower limit of detection, or LOD (limit of detection), often mistakenly confused with the analytical sensitivity, is the lowest quantity of a substance that can be distinguished from the absence of that substance (a '' blank value'') with a stated confidence level (generally 99%). The detection limit is estimated from the mean of the blank, the standard deviation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Background Radiation
Background radiation is a measure of the level of ionizing radiation present in the environment at a particular location which is not due to deliberate introduction of radiation sources. Background radiation originates from a variety of sources, both natural and artificial. These include both cosmic radiation and environmental radioactivity from naturally occurring radioactive materials (such as radon and radium), as well as man-made medical X-rays, fallout from nuclear weapons testing and nuclear accidents. Definition Background radiation is defined by the International Atomic Energy Agency as "Dose or dose rate (or an observed measure related to the dose or dose rate) attributable to all sources other than the one(s) specified. So a distinction is made between dose which is already in a location, which is defined here as being "background", and the dose due to a deliberately introduced and specified source. This is important where radiation measurements are taken of a specifie ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Low-background Steel
Low-background steel, also known as pre-war steel, is any steel produced prior to the detonation of the first nuclear bombs in the 1940s and 1950s. Typically sourced from shipwrecks and other steel artifacts of this era, it is often used for modern particle detectors because more modern steel is contaminated with traces of nuclear fallout. Since the cessation of atmospheric nuclear testing, background radiation has decreased to very near natural levels, making special low-background steel no longer necessary for most radiation-sensitive applications, as brand-new steel now has a low enough radioactive signature that it can generally be used in such applications. However, some demand remains for the most radiation-sensitive applications, such as Geiger counters and sensing equipment aboard spacecraft, and World War II-era shipwrecks near in the Java Sea and western South China Sea are often illegally scavenged for low-background steel. Radionuclide contamination From 1856 until t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Potassium
Potassium is the chemical element with the symbol K (from Neo-Latin ''kalium'') and atomic number19. Potassium is a silvery-white metal that is soft enough to be cut with a knife with little force. Potassium metal reacts rapidly with atmospheric oxygen to form flaky white potassium peroxide in only seconds of exposure. It was first isolated from potash, the ashes of plants, from which its name derives. In the periodic table, potassium is one of the alkali metals, all of which have a single valence electron in the outer electron shell, that is easily removed to create an ion with a positive charge – a cation, that combines with anions to form salts. Potassium in nature occurs only in ionic salts. Elemental potassium reacts vigorously with water, generating sufficient heat to ignite hydrogen emitted in the reaction, and burning with a lilac- colored flame. It is found dissolved in sea water (which is 0.04% potassium by weight), and occurs in many minerals such as orthoclase, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Caesium-137
Caesium-137 (), cesium-137 (US), or radiocaesium, is a radioactive isotope of caesium that is formed as one of the more common fission products by the nuclear fission of uranium-235 and other fissionable isotopes in nuclear reactors and nuclear weapons. Trace quantities also originate from spontaneous fission of uranium-238. It is among the most problematic of the short-to-medium-lifetime fission products. Caesium-137 has a relatively low boiling point of and is volatilized easily when released suddenly at high temperature, as in the case of the Chernobyl nuclear accident and with atomic explosions, and can travel very long distances in the air. After being deposited onto the soil as radioactive fallout, it moves and spreads easily in the environment because of the high water solubility of caesium's most common chemical compounds, which are salts. Caesium-137 was discovered by Glenn T. Seaborg and Margaret Melhase. Decay Caesium-137 has a half-life of about 30.05 years. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stand-up WBC
Stand-up comedy is a comedic performance to a live audience in which the performer addresses the audience directly from the stage. The performer is known as a comedian, a comic or a stand-up. Stand-up comedy consists of one-liners, stories, observations or a shtick that may incorporate props, music, magic tricks or ventriloquism. It can be performed almost anywhere, including comedy clubs, comedy festivals, bars, nightclubs, colleges or theatres. History Stand-up as a Western art form has its roots in the stump speech of American minstrel shows, which featured an actor in blackface delivering nonsensical monologue to the audience. While the intention of stump speeches was to mock African-Americans, they also occasionally contained political and social satire. The minstrel show would later influence theatrical traditions of the late 19th and early 20th centuries, such as vaudeville and burlesque. The first documented use of "stand-up" as a term was in ''The Stage'' in 19 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Scanning Bed WBC
Scan may refer to: Acronyms * Schedules for Clinical Assessment in Neuropsychiatry (SCAN), a psychiatric diagnostic tool developed by WHO * Shared Check Authorization Network (SCAN), a database of bad check writers and collection agency for bad checks * Space Communications and Navigation Program (SCaN) * Social Cognitive and Affective Neuroscience (journal) * Scientific content analysis (SCAN), also known as statement analysis Businesses * Scan Furniture, Washington, D.C., US chain * SCAN Health Plan, not-for-profit health care company based in Long Beach, California * Scan AB or Scan Foods UK Ltd, the Swedish and UK subsidiaries of the Finnish HKScan Oyj * Seattle Community Access Network, Seattle, Washington, US TV channel * Scan (company), a software company based in Provo, Utah, US Electronics or computer related * 3D scanning * Counter-scanning, in physical micro and nanotopography measuring instruments like scanning probe microscope * Elevator algorithm (also SCAN ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
