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  • Nuclear
  • This seemingly authoritative declaration that the Philippines is 'safe' from radiation should not be allowed to blind the public to the real dangers brought about by the Japan Nuclear Reactor Disaster which has already surpassed the Three Mile Island incident and is alarmingly approaching the scale of the Chernobyl catastrophe. (abs-cbn.com)
  • Rather than downplaying a very serious catastrophe confronting the entire world and misleading the people, the government should address the full spectrum of public health and environmental problems caused by the release of ionizing radiation from the Fukushima Nuclear Power Plants. (abs-cbn.com)
  • The authorities apparently refer to the so-called standards of permissible or acceptable limits set by the International Commission on Radiation Protection (ICRP) and the US Nuclear Regulatory Commission as basis for declaring that exposure levels of the public are 'small' and within 'safety' limits and that significant risk of harm is limited to the immediate vicinity of the power plants. (abs-cbn.com)
  • Since the decision makers, were either users of ionizing radiation in their employment, or are government regulators, primarily from countries with nuclear weapon programs, the vested interests are very clear. (abs-cbn.com)
  • The characteristic blue glow of an underwater nuclear reactor is due to Cherenkov radiation. (wikipedia.org)
  • Devices intended for high radiation environments such as the nuclear industry and extra atmospheric (space) applications may be made radiation hard to resist such effects through design, material selection, and fabrication methods. (wikipedia.org)
  • This is of special concern as it can greatly affect their ability to perform in nuclear reactors and is the emphasis of radiation material science, which seeks to mitigate this danger. (wikipedia.org)
  • As concrete is used extensively in the construction of nuclear power plants, where it provides structure as well as containing radiation, the effect of radiation on it is also of major interest. (wikipedia.org)
  • Nuclear weapons have vastly widened the scope of attention, and the layman has long recognized that he lives in an age when radiation is a highly publicized fact of life. (encyclopedia.com)
  • Like all procedures that involve a radioactive substance, nuclear medicine techniques that use radiopharmaceuticals generate radiation that could potentially have adverse effects on a patient. (news-medical.net)
  • Therefore, as a general rule, the amount of exposure during a nuclear medicine procedure is kept "As Low As Reasonably Practicable" (ALARP), meaning that the smallest dose of radiation possible is used that will still achieve accurate results. (news-medical.net)
  • The radiation dose from a nuclear medicine procedure is measured in units of sieverts (usually in millisieverts, mSv). (news-medical.net)
  • This 'Canned Radiation' produced by Brenster Enterprises in 1980 was probably the most popular souvenir from the Three Mile Island nuclear incident. (neatorama.com)
  • If the source of the ionizing radiation is a radioactive material or a nuclear process such as fission or fusion, there is particle radiation to consider. (wikipedia.org)
  • Particle radiation is subatomic particles accelerated to relativistic speeds by nuclear reactions. (wikipedia.org)
  • Sources include cosmic radiation, and environmental radioactivity from such as naturally occurring radioactive materials including radon and radium, and fallout from nuclear weapons testing and nuclear accidents. (wikipedia.org)
  • Cyclotron radiation would likely be produced in a high altitude nuclear explosion. (wikipedia.org)
  • The term 'biological shield' is used for absorbing material placed around a nuclear reactor, or other source of radiation, to reduce the radiation to a level safe for humans. (wikipedia.org)
  • Ionizing radiation is used in a wide variety of fields such as medicine, nuclear power, research, manufacturing, construction, and many other areas, but presents a health hazard if proper measures against undesired exposure aren't followed. (wikipedia.org)
  • doses
  • Highly radiosensitive cancer cells are rapidly killed by modest doses of radiation. (wikipedia.org)
  • Radiation doses should all be kept as low as reasonably achievable ( ALARA ). (wikipedia.org)
  • This means that it is not enough to remain under the radiation dose limits, but that radiation doses are as low as reasonably achievable, which often means much lower than the permitted limit. (wikipedia.org)
  • An example of reducing radiation doses by reducing the time of exposures might be improving operator training to reduce the time they take to handle a radioactive source. (wikipedia.org)
  • In much higher doses, radiation is used to treat cancer. (kidshealth.org)
  • Normal cells are more likely to recover from its effects, though, and the health care team will take extensive measures to carefully monitor a child's radiation doses to protect healthy tissue. (kidshealth.org)
  • Receiving small daily doses of radiation helps to protect the normal cells from damage, while weekend breaks help them recover from the trauma of radiation. (kidshealth.org)
  • 1965), doses of a few hundred rads to the whole body will cause death within days, while doses of several thousands of rads are delivered to focal points of the body in radiation therapy without lethal effect. (encyclopedia.com)
  • Because one of the basic premises of homeopathic medicine is that small doses of a treatment can help to heal those symptoms that large doses are known to cause, Ludlam suggested to Grubbe that radiation may be a treatment for conditions such as tumors because it also causes them. (huffingtonpost.com)
  • Radiation hormesis is the hypothesis that low doses of ionizing radiation (within the region of and just above natural background levels) are beneficial, stimulating the activation of repair mechanisms that protect against disease, that are not activated in absence of ionizing radiation. (wikipedia.org)
  • While the effects of high and acute doses of ionising radiation are easily observed and understood in humans (e.g. (wikipedia.org)
  • However, children are particularly sensitive to radioactivity, with childhood leukemias and other cancers increasing even within natural and man-made background radiation levels (under 4 mSv cumulative with 1 mSv being an average annual dose from terrestrial and cosmic radiation excluding radon which primarily doses the lung). (wikipedia.org)
  • Radiation hormesis stands in stark contrast to the more generally accepted linear no-threshold model (LNT), which states that the radiation dose-risk relationship is linear across all doses, so that small doses are still damaging, albeit less so than higher ones. (wikipedia.org)
  • Similarly, many of the common, moderately radioresponsive tumors are routinely treated with curative doses of radiation therapy if they are at an early stage. (wikipedia.org)
  • Chronic radiodermatitis occurs with chronic exposure to "sub-erythema" doses of ionizing radiation over a prolonged period, producing varying degrees of damage to the skin and its underlying parts after a variable latent period of several months to several decades. (wikipedia.org)
  • tissue
  • During external beam radiation therapy, a machine directs radiation through the skin to the tumour and some of the tissue around it. (cancer.ca)
  • To spare normal tissues (such as skin or organs which radiation must pass through to treat the tumor), shaped radiation beams are aimed from several angles of exposure to intersect at the tumor, providing a much larger absorbed dose there than in the surrounding, healthy tissue. (wikipedia.org)
  • Brachytherapy , in which a radioactive source is placed inside or next to the area requiring treatment, is another form of radiation therapy that minimizes exposure to healthy tissue during procedures to treat cancers of the breast, prostate and other organs. (wikipedia.org)
  • Another type, proton-beam radiation therapy, better focuses the radiation on the cancerous tissue with the goal of causing less harm to the surrounding healthy tissue. (kidshealth.org)
  • The effects of these radiations on chemical systems and living tissue are caused primarily by heating effects from the combined energy transfer of many photons. (wikipedia.org)
  • atoms
  • Radiation can also lead to segregation and diffusion of atoms within materials, leading to phase segregation and voids as well as enhancing the effects of stress corrosion cracking through changes in both the water chemistry and alloy microstructure. (wikipedia.org)
  • The polonium isotope discovered in Litvinenko's body emits radiation only in the form of alpha particles , which are the charged nuclei of helium atoms. (slate.com)
  • While an individual cell is made of trillions of atoms, only a small fraction of those will be ionized at low to moderate radiation powers. (wikipedia.org)
  • thermal radiation
  • All matter with a temperature greater than absolute zero emits thermal radiation. (wikipedia.org)
  • Examples of thermal radiation include the visible light and infrared light emitted by an incandescent light bulb, the infrared radiation emitted by animals that is detectable with an infrared camera, and the cosmic microwave background radiation. (wikipedia.org)
  • Thermal radiation is different from thermal convection and thermal conduction-a person near a raging bonfire feels radiant heating from the fire, even if the surrounding air is very cold. (wikipedia.org)
  • Sunlight is part of thermal radiation generated by the hot plasma of the Sun. The Earth also emits thermal radiation, but at a much lower intensity and different spectral distribution (infrared rather than visible) because it is cooler. (wikipedia.org)
  • The Earth's absorption of solar radiation, followed by its outgoing thermal radiation, are the two most important processes that determine the temperature and climate of the Earth in most climate models. (wikipedia.org)
  • Thermal radiation is one of the fundamental mechanisms of heat transfer. (wikipedia.org)
  • Thermal radiation, also known as heat, is the emission of electromagnetic waves from all matter that has a temperature greater than absolute zero. (wikipedia.org)
  • The characteristics of thermal radiation depend on various properties of the surface it is emanating from, including its temperature, its spectral absorptivity and spectral emissive power, as expressed by Kirchhoff's law. (wikipedia.org)
  • Thus, to thermal radiation it appears black. (wikipedia.org)
  • background radiation
  • Background radiation originates from a variety of sources, both natural and artificial. (wikipedia.org)
  • For example, in considering radiation safety , 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. (wikipedia.org)
  • However, if no specific radiation source is of concern, then the total radiation dose measurement taken at a location is generally called the background radiation , and this is usually the case where an ambient dose rate is measured for environmental purposes. (wikipedia.org)
  • Background radiation varies with location and time, and the following table gives examples: Radioactive material is found throughout nature. (wikipedia.org)
  • The biggest source of natural background radiation is airborne radon, a radioactive gas that emanates from the ground. (wikipedia.org)
  • The widespread construction of well insulated and sealed homes in the northern industrialized world has led to radon becoming the primary source of background radiation in some localities in northern North America and Europe. (wikipedia.org)
  • chemotherapy
  • Radiation therapy is synergistic with chemotherapy , and has been used before, during, and after chemotherapy in susceptible cancers. (wikipedia.org)
  • It is also common to combine radiation therapy with surgery , chemotherapy, hormone therapy , immunotherapy or some mixture of the four. (wikipedia.org)
  • Some kids receive radiation therapy alone, while others need both radiation and chemotherapy (the use of medicines to destroy cancer cells). (kidshealth.org)
  • Cherenkov
  • Cherenkov radiation glowing in the core of the Advanced Test Reactor . (wikipedia.org)
  • Cherenkov radiation in the Reed Research Reactor . (wikipedia.org)
  • It is also known as the Vavilov-Cherenkov radiation ( VCR ) (named after Sergey Vavilov and Pavel Cherenkov ). (wikipedia.org)
  • Cherenkov radiation had been theoretically predicted by the English polymath Oliver Heaviside in papers published in 1888-89. (wikipedia.org)
  • The geometry of the Cherenkov radiation (shown for the ideal case of no dispersion). (wikipedia.org)
  • However, some misconceptions regarding Cherenkov radiation exist, for example, it is believed that the medium becomes electrically polarized by the particle's electric field. (wikipedia.org)
  • However, high intensities can cause emission of visible light upon interaction with matter, such as in Cherenkov radiation and radioluminescence. (wikipedia.org)
  • photons
  • In quantum mechanics , radiation pressure can be interpreted as the transfer of momentum from photons as they strike a surface. (daviddarling.info)
  • By analogy to the way photons mediate electromagnetic interactions between particles in the Standard Model (called baryonic matter in cosmology), dark radiation is proposed to mediate interactions between dark matter particles. (wikipedia.org)
  • cancers
  • Other radiation-related human tragedies such as earlier occurrence of cancers, endocrine disorders, immune dysfunction, developmental disorders, and other illnesses are not included. (abs-cbn.com)
  • The use of radiation therapy in non-malignant conditions is limited partly by worries about the risk of radiation-induced cancers. (wikipedia.org)
  • Combining radiation therapy with immunotherapy is an active area of investigation and has shown some promise for melanoma and other cancers. (wikipedia.org)
  • Most kids receive only external radiation therapy, although those with cancers of the head and neck, uterus, cervix, thyroid, and testes may also undergo internal radiation therapy. (kidshealth.org)
  • Different cancers respond to radiation therapy in different ways. (wikipedia.org)
  • ICRP
  • Thus, it is quite clear that even the ICRP recognizes that radiation exposure below 'acceptable' levels could actually cause adverse health effects. (abs-cbn.com)
  • For radiation protection and dosimetry assessment the International Committee on Radiation Protection (ICRP) and International Commission on Radiation Units and Measurements (ICRU) have published recommendations and data which is used to calculate the biological effects on the human body, and thereby advise dose uptake limits. (wikipedia.org)
  • In most countries a national regulatory authority works towards ensuring a secure radiation environment in society by setting dose limitation requirements that are generally based on the recommendations of the ICRP. (wikipedia.org)
  • Measurements
  • Reports by the United States National Research Council and the National Council on Radiation Protection and Measurements and the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) argue that there is no evidence for hormesis in humans and in the case of the National Research Council hormesis is outright rejected as a possibility. (wikipedia.org)
  • This is important where radiation measurements are taken of a specified radiation source, and the incidental background may affect this measurement. (wikipedia.org)
  • rems
  • It further stated that: 'The commission believes that this level [5 rems radiation exposure per 30 years for the general public] provides reasonable latitude for the expansion of atomic energy programs in the foreseeable future. (abs-cbn.com)
  • high exposures
  • Even though Grubbe had to have one hand amputated early in life due to the high exposures received from his early experiences with radiation, he ultimately lived a long and full life of 85 years, in part due to the homeopathic treatment he received throughout his life. (huffingtonpost.com)
  • spectrum
  • Since there are an infinite number of modes this implies infinite heat capacity (infinite energy at any non-zero temperature), as well as an unphysical spectrum of emitted radiation that grows without bound with increasing frequency, a problem known as the ultraviolet catastrophe . (wikipedia.org)
  • This results in charge-acceleration and/or dipole oscillation which produces electromagnetic radiation, and the wide spectrum of radiation reflects the wide spectrum of energies and accelerations that occur even at a single temperature. (wikipedia.org)
  • Planck's law describes the spectrum of blackbody radiation, which depends only on the object's temperature. (wikipedia.org)
  • The radiation is not monochromatic, i.e., it does not consist of just a single frequency, but comprises a continuous dispersion of photon energies, its characteristic spectrum. (wikipedia.org)
  • Cyclotron radiation has a spectrum with its main spike at the same fundamental frequency as the particle's orbit, and harmonics at higher integral factors. (wikipedia.org)
  • molecules
  • In the atmosphere such particles are often stopped by air molecules, and this produces short-lived charged pions, which soon decay to muons, a primary type of cosmic ray radiation that reaches the ground (and also penetrates it to some extent). (wikipedia.org)
  • intensity
  • The official line about the type and intensity of radiation exposure we face seems to change every day everywhere. (huffingtonpost.com)
  • Like any ideal law, the inverse-square law approximates a measured radiation intensity to the extent that the source approximates a geometric point. (wikipedia.org)
  • Wien's displacement law determines the most likely frequency of the emitted radiation, and the Stefan-Boltzmann law gives the radiant intensity. (wikipedia.org)
  • amount of radiation
  • Your healthcare team will consider your personal needs to plan the type and amount of radiation, and when and how it is given. (cancer.ca)
  • The therapist will leave, and a large machine will then deliver the exact amount of radiation needed to kill the cells in the cancerous area. (kidshealth.org)
  • cancer
  • Answers common questions, such as what radiation therapy is and how it affects cancer cells. (cancer.gov)
  • Radiation therapy uses high-energy rays or particles to destroy cancer cells. (cancer.ca)
  • You may have radiation therapy to relieve pain or control the symptoms of advanced kidney cancer (called palliative therapy). (cancer.ca)
  • Radiation therapy may be curative in a number of types of cancer if they are localized to one area of the body. (wikipedia.org)
  • The response of a cancer to radiation is described by its radiosensitivity. (wikipedia.org)
  • Renal cell cancer and melanoma are generally considered to be radioresistant but radiation therapy is still a palliative option for many patients with metastatic melanoma. (wikipedia.org)
  • It is important to distinguish the radiosensitivity of a particular tumor, which to some extent is a laboratory measure, from the radiation "curability" of a cancer in actual clinical practice. (wikipedia.org)
  • But parents whose kids need radiation therapy - one of the most common treatments for childhood cancer - often have many questions and concerns about it. (kidshealth.org)
  • But besides destroying cancer cells, radiation therapy also can harm normal cells. (kidshealth.org)
  • A homeopath by the name of Emil Grubbe, M.D. (1875-1960) was the first person to use radiation to treat a person with cancer (Dearborn, 2005). (huffingtonpost.com)
  • He gave radiation treatment to Mrs. Rose Lee, a woman with breast cancer. (huffingtonpost.com)
  • Grubbe got the idea of using radiation as a treatment for Lee's breast cancer from Reuben Ludlam, M.D., a professor at the homeopathic medical school. (huffingtonpost.com)
  • This is because the baseline cancer rate is already very high and the risk of developing cancer fluctuates 40% because of individual life style and environmental effects, obscuring the subtle effects of low-level radiation. (wikipedia.org)
  • Older people have much higher cancer rates even in the absence of excess radiation exposure. (wikipedia.org)
  • Radiation therapy can also cause radiation cancer. (wikipedia.org)
  • tumour
  • Besides the tumour itself, the radiation fields may also include the draining lymph nodes if they are clinically or radiologically involved with tumor, or if there is thought to be a risk of subclinical malignant spread. (wikipedia.org)
  • hazards
  • Perhaps the most recent application of this field to applied sciences has taken place since the advent of the space age, when those concerned with the effects of unusual environmental conditions upon man have focused attention on the radiation hazards in space (Hanrahan & Bushnell 1960, pp. 155-188). (encyclopedia.com)
  • existence
  • Government and regulatory bodies disagree on the existence of radiation hormesis and research points to the "severe problems and limitations" with the use of hormesis in general as the "principal dose-response default assumption in a risk assessment process charged with ensuring public health protection. (wikipedia.org)
  • frequency
  • Radiation burns can also occur with high power radio transmitters at any frequency where the body absorbs radio frequency energy and converts it to heat. (wikipedia.org)
  • concern
  • Since the inception of radiation research, the biomedical literature has reflected concern with behavioral data in terms of their application to diagnosis, abnormal growth patterns, heredity, and lethality. (encyclopedia.com)
  • The psychologist studying radiation must concern himself with them individually and in combinations. (encyclopedia.com)
  • emission
  • Further, the Japanese are working to reduce radiation emission by dousing the container with graphite and borax, both of which may change the nature of the emissions. (huffingtonpost.com)
  • include
  • Other familiar radiations include the Cambrian explosion, the Avalon explosion, the Great Ordovician Biodiversification Event, the Mesozoic-Cenozoic Radiation, the radiation of land plants after their colonisation of land, the Cretaceous radiation of angiosperms, and the diversification of insects, a radiation that has continued almost unabated since the Devonian, 400 million years ago. (wikipedia.org)
  • occurs
  • Restated, radiation recall dermatitis is an inflammatory skin reaction that occurs in a previously irradiated body part following drug administration. (wikipedia.org)