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Christopher Busby
Christopher Busby (born 1 September 1945) is a British scientist primarily studying the health effects of internal ionising radiation. Busby is a director of Green Audit Limited, a private company, and scientific advisor to the Low Level Radiation Campaign (LLRC). Following the 2011 Fukushima Daiichi nuclear disaster, Busby established a television and internet presence where he discussed the risks of ionizing radiation and the Japanese Government's handling of the disaster. A Japanese language website marketed tests and a mineral supplement (dubbed an "anti-radiation" pill, and condemned by leading scientists as "useless") that Busby advised could mitigate the effects of ingested radioisotopes. Career Busby obtained a BSc in Chemistry with First Class Honours from the University of London. He later gained a PhD in chemical physics at the University of Kent, researching Raman spectro-electrochemistry. Busby was a member of the British government sponsored Committee Examining ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Linear No-threshold Model
The linear no-threshold model (LNT) is a dose-response model used in radiation protection to estimate stochastic health effects such as radiation-induced cancer, genetic mutations and teratogenic effects on the human body due to exposure to ionizing radiation. The model statistically extrapolates effects of radiation from very high doses (where they are observable) into very low doses, where no biological effects may be observed. The LNT model lies at a foundation of a postulate that all exposure to ionizing radiation is harmful, regardless of how low the dose is, and that the effect is cumulative over lifetime. The LNT model is commonly used by regulatory bodies as a basis for formulating public health policies that set regulatory dose limits to protect against the effects of radiation. The model has also been used in the assessment of cancer risks of mutagenic chemicals. The validity of the LNT model, however, is disputed, and other significant models exist: the threshold mo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radiation Hormesis
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. The reserve repair mechanisms are hypothesized to be sufficiently effective when stimulated as to not only cancel the detrimental effects of ionizing radiation but also inhibit disease not related to radiation exposure (see hormesis). This hypothesis has captured the attention of scientists and public alike in recent years. While the effects of high and acute doses of ionising radiation are easily observed and understood in humans (''e.g.'' Japanese atomic bomb survivors), the effects of low-level radiation are very difficult to observe and highly controversial. This is because the baseline cancer rate is already very high and the risk of developing cancer fluctuates 40% because of individual l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Committee On Medical Aspects Of Radiation In The Environment
The Committee on Medical Aspects of Radiation in the Environment (COMARE) is a UK-wide advisory committee set up by the British government. It was established in 1985. Terms of reference and function The terms of reference of COMARE are: "to assess and advise Government and the devolved authorities on the health effects of natural and man-made radiation and to assess the adequacy of the available data and the need for further research". COMARE is an independent expert advisory committee with members chosen for their medical and scientific expertise and recruited from universities, research and medical institutes. Members have never been drawn from the nuclear or electrical power supply industries. The committee offers independent advice to all government departments and devolved authorities, not just the health departments, and is responsible for assessing and advising them on the health effects of natural and man-made radiation. It is also asked to assess the adequacy of the av ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cell Cycle
The cell cycle, or cell-division cycle, is the series of events that take place in a cell that cause it to divide into two daughter cells. These events include the duplication of its DNA (DNA replication) and some of its organelles, and subsequently the partitioning of its cytoplasm, chromosomes and other components into two daughter cells in a process called cell division. In cells with nuclei ( eukaryotes, i.e., animal, plant, fungal, and protist cells), the cell cycle is divided into two main stages: interphase and the mitotic (M) phase (including mitosis and cytokinesis). During interphase, the cell grows, accumulating nutrients needed for mitosis, and replicates its DNA and some of its organelles. During the mitotic phase, the replicated chromosomes, organelles, and cytoplasm separate into two new daughter cells. To ensure the proper replication of cellular components and division, there are control mechanisms known as cell cycle checkpoints after each of the key s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radiosensitivity
Radiosensitivity is the relative susceptibility of cells, tissues, organs or organisms to the harmful effect of ionizing radiation. Cells types affected Cells are least sensitive when in the S phase, then the G1 phase, then the G2 phase, and most sensitive in the M phase of the cell cycle. This is described by the 'law of Bergonié and Tribondeau', formulated in 1906: X-rays are more effective on cells which have a greater reproductive activity. From their observations, they concluded that quickly dividing tumor cells are generally more sensitive than the majority of body cells. This is not always true. Tumor cells can be hypoxic and therefore less sensitive to X-rays because most of their effects are mediated by the free radicals produced by ionizing oxygen. It has meanwhile been shown that the most sensitive cells are those that are undifferentiated, well nourished, dividing quickly and highly active metabolically. Amongst the body cells, the most sensitive are spermato ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
G2 Phase
G2 phase, Gap 2 phase, or Growth 2 phase, is the third subphase of interphase in the cell cycle directly preceding mitosis. It follows the successful completion of S phase, during which the cell’s DNA is replicated. G2 phase ends with the onset of prophase, the first phase of mitosis in which the cell’s chromatin condenses into chromosomes. G2 phase is a period of rapid cell growth and protein synthesis during which the cell prepares itself for mitosis. Curiously, G2 phase is not a necessary part of the cell cycle, as some cell types (particularly young ''Xenopus'' embryos and some cancers)) proceed directly from DNA replication to mitosis. Though much is known about the genetic network which regulates G2 phase and subsequent entry into mitosis, there is still much to be discovered concerning its significance and regulation, particularly in regards to cancer. One hypothesis is that the growth in G2 phase is regulated as a method of cell size control. Fission yeast (''S ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Strontium 90
Strontium-90 () is a radioactive isotope of strontium produced by nuclear fission, with a half-life of 28.8 years. It undergoes β− decay into yttrium-90, with a decay energy of 0.546 MeV. Strontium-90 has applications in medicine and industry and is an isotope of concern in fallout from nuclear weapons, nuclear weapons testing, and nuclear accidents. Radioactivity Naturally occurring strontium is nonradioactive and nontoxic at levels normally found in the environment, but 90Sr is a radiation hazard. 90Sr undergoes β− decay with a half-life of 28.79 years and a decay energy of 0.546 MeV distributed to an electron, an antineutrino, and the yttrium isotope 90Y, which in turn undergoes β− decay with a half-life of 64 hours and a decay energy of 2.28 MeV distributed to an electron, an antineutrino, and 90Zr (zirconium), which is stable. Note that 90Sr/Y is almost a pure beta particle source; the gamma photon emission from the decay of 90Y is so infrequent that i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Decay Chain
In nuclear science, the decay chain refers to a series of radioactive decays of different radioactive decay products as a sequential series of transformations. It is also known as a "radioactive cascade". Most radioisotopes do not decay directly to a stable state, but rather undergo a series of decays until eventually a stable isotope is reached. Decay stages are referred to by their relationship to previous or subsequent stages. A ''parent isotope'' is one that undergoes decay to form a ''daughter isotope''. One example of this is uranium (atomic number 92) decaying into thorium (atomic number 90). The daughter isotope may be stable or it may decay to form a daughter isotope of its own. The daughter of a daughter isotope is sometimes called a ''granddaughter isotope''. The time it takes for a single parent atom to decay to an atom of its daughter isotope can vary widely, not only between different parent-daughter pairs, but also randomly between identical pairings of parent ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Self-published
Self-publishing is the publication of media by its author at their own cost, without the involvement of a publisher. The term usually refers to written media, such as books and magazines, either as an ebook or as a physical copy using POD (print on demand) technology. It may also apply to albums, pamphlets, brochures, games, video content, artwork, and zines. Web fiction is also a major medium for self-publishing. Definitions Although self-publishing is not a new phenomenon, dating back to the 18th century, it has transformed during the internet age with new technologies and services providing increasing alternatives to traditional publishing, becoming a $1 billion market.Jennifer Alsever, Fortune magazine, 30 December 2016The Kindle Effect Retrieved 9 November 2017, "...has become a $1 billion industry..." However, with the increased ease of publishing and the range of services available, confusion has arisen as to what constitutes self-publishing. In 2022, the Society ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nova Science Publishers, Inc
A nova (plural novae or novas) is a transient astronomical event that causes the sudden appearance of a bright, apparently "new" star (hence the name "nova", which is Latin for "new") that slowly fades over weeks or months. Causes of the dramatic appearance of a nova vary, depending on the circumstances of the two progenitor stars. All observed novae involve white dwarfs in close binary systems. The main sub-classes of novae are classical novae, recurrent novae (RNe), and dwarf novae. They are all considered to be cataclysmic variable stars. Classical nova eruptions are the most common type. They are likely created in a close binary star system consisting of a white dwarf and either a main sequence, subgiant, or red giant star. When the orbital period falls in the range of several days to one day, the white dwarf is close enough to its companion star to start drawing accreted matter onto the surface of the white dwarf, which creates a dense but shallow atmosphere. This atmos ... [...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 spe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
