...Ozone Layer Depletion: Introduction Are we damaging our protective blanket? Sunlight contains some ultraviolet light, and when we expose ourselves to too much of it, we get a sunburn. Over time, too much exposure to ultraviolet light can lead to cataracts and skin cancer. The earth has a layer in the upper atmosphere, consisting mostly of ozone gas, that filters out most of the ultraviolet in the sun's radiation. Recently there has been scientific evidence that we have been releasing gases that damage this layer. Our country and others have reacted by invoking legislation that should eliminate these contaminants from the atmosphere. What does the Ozone Layer do? * Ozone absorbs 99% of the harmful ultraviolet (UV) radiation. Without the Ozone Layer * Most of the harmful UV radiation will penetrate the atmosphere. The Ozone Layer The ozone layer is a layer in Earth's atmosphere which contains relatively high concentrations of ozone (O3). This layer absorbs 97-99% of the sun's high frequency ultraviolet light, which is potentially damaging to life on earth. Over 90% of ozone in earth's atmosphere is present here "Relatively high" means a few parts per million—much higher than the concentrations in the lower atmosphere but still small compared to the main components of the atmosphere. It is mainly located in the lower portion...
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...Biological Safety Cabinets (BSC) and set forth a position based on the risk and benefits. Background Ultraviolet (UV) radiation is a form of nonionizing radiation and behaves in accordance with the laws and principles of geometric optics. Electromagnetic radiation can be described as a “wave” that consists of an electric field and a magnetic field. Electromagnetic radiation is usually characterized by wavelength and frequency or photon energy. The term wavelength refers to a distance in a line of advance of a wave from any point to a like point on the next wave; it corresponds to the distance traveled by the wave during one cycle. A wavelength is usually measured in angstroms or nanometers (nm). The International Commission on Illumination (CIE) has divided the UV spectrum into three wavelength bands, primarily due to biological effects. The 315-400 nm wavelength band is designated as UV-A. 280-315 nm is designated as UV-B, and 100-280 nm as UV-C. Wavelengths below 180 nm are of little practical biological significance since the atmosphere readily absorbs them. Sources of UV-A are used for dentistry and tanning, UVB is used for fade testing and photocuring of plastics, and UV-C (100-280 nm) is used for germicidal purposes. All wavelengths less than 320 nm are actinic, meaning they are capable of causing chemical reactions. The mechanism of the germicidal effect involves these chemical reactions and so effectiveness varies by composition of the target organism in addition to physical...
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...Radiation is all around us and has been present since the beginning of time. Naturally occurring radioactive materials were discovered in 1896. Less than 50 years later, the physicist Enrico Fermi split the atom, producing the first man-made radioactive materials (Robert Brent MD). We used radioactive materials for beneficial purposes, such as generating electricity, diagnosing and treating medical problems. Man-made source of radiation from medical, commercial and industrial activities contribute about 310mrem to the annual radiation exposure. One of the largest of these sources of exposure is a CT scan, which account for about 150mrem. Radiation can cause adverse effects, including genetic defects in the children of exposed parents or mental retardation in the children of mother exposed during pregnancy. Most diagnostic procedures expose the embryo to less than 5 rad or 50mSv. This level of exposure will not increase reproductive risks. Potential radiation effects vary depending on the fetal stage of development and the magnitude of the dose. In the first two weeks post-conception the embryo is very resistant to the malformation effects of x-rays. The embryo is, however, sensitive to the lethal affects of x-ray, although doses much higher than 5 rad or 50mSv can cause a miscarriage. From the third to eighth week of pregnancy the embryo is in the period of early embryonic development but is not affected with birth defects, pregnancy loss, or growth retardation unless the exposure...
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...stringent Electromagnetic Frequency Radiation Standards. epartment of Telecommunication (DoT) is all set to implement the new policy and regulation on electromagnetic radiation emitted by Mobile Tower and Handsets from today i.e. September 1. The policy is to made in corcern for the safety issues over health hazards due to radiations emitting from Mobile Tower and Mobile phones. With the implementation of these norms Indian standards would now be 10 times more stringent than more than 90% countries in the world. From September 1st 2012, for all mobile towers that must reduce emission to one-tenth of the present limits else face penalties of Rs 5 lakh per tower. While for Mobile handsets manufactured and sold in India or Imported from any other countries should be checked for compliance of Specific Absorption Limit. No handsets of SAR value above the prescribed standard adopted in India should be manufactured or sold in the country. Department of Telecommunications has recommended that the radiation level per cell tower should be less than 1-watt per sq metre-reducing it to 1/10th the current permissible norm. All research points out to the impact on the human immune and nervous systems, complications in reproductive health as well as behavioural problems in children. He emphasised that all epidemiological studies point out to adverse impact of mobile radio especially on children, pregnant women and on male fertility. radiation has two effects-thermal and non-thermal. The present...
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...Radiation Effects at the Tissue and Organ Level * Response to irradiation- measures the radiosensitivity of tissue or organ * Loss of moderate number of cells- does not affect function of organs * Loss of large number of cells- display clinical result * Severity of change depends on dose and thus amount of cell loss * Repairable damage- moderate dose to localized area * Death from damage to most sensitive system- comparable dose to whole organism Short- Term Effects * Sensitivity of parenchymal cell- determines short term effect of radiation on a tissue * Lost cells in mitosis- linked death- when continuously proliferating tissues (e.g bone marrow, oral mucous membrane) are irradiated with a moderate dose * Extent of cell loss depends on damage to stem cell pools and proliferative rate of cell population * Reduction in number of mature cells- effect of irradiation to such tissues * Little or no radiation-induced hypoplasia- when tissues composed of cells that rarely or never divide (e.g muscle) are irradiated Long- Term Effects * Damage to fine vasculature- determines long-term effect of radiation on tissue or organ * Radio sensitivity of capillaries and connective tissues- differentiating intermiotic cells and reverting postmiotic cells * Irradiation of capillaries- swelling, degeneration, necrosis * Increases capillary permeability and slow progressive fibrosis around vessels * Increased...
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...impairs many treatments that may be administered. Treatments for lung cancer include but are not limited to radiation, chemotherapy and surgery. Starting with surgery, there is more than one option available. In acute situations a small portion of the lung can be removed called a wedge resection. This can result in the least amount of residual damage to other areas of the lung as well as shorten recovery time significantly. Next there is the segmental resection which removes a larger portion but not an entire lobe. When larger parts of the lung are affected by cancer a lobectomy can be done which is the removal of an entire lobe of a lung and finally a complete removal of a lung, called pneumonectomy. Sometimes during any of the above stated procedures, the “surgeon may also remove lymph nodes from your chest in order to check them for signs of cancer” (www.mayoclinic.org). With any surgery there are risks involved including difficulty breathing and infections. Chemotherapy is another option available to patients with a non-surgical form of adenocarcinoma. “Chemotherapy uses drugs to kill cancer cells.”(www.mayoclinic.org). Chemotherapy has been shown to be effective post-surgery to destroy any remaining cancer cells and sometimes it is used prior to surgery in an attempt to reduce the size of the cells for ease of removal before surgery is attempted. Adverse reactions to chemotherapy can be quite severe because of the high toxicity of the drugs used. Chemotherapy...
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...Cause-effect relationships: climate change, ozone layer depletion, ultra violet radiation and biodiversity changes Ultraviolet radiation and ozone layer In recent years, along with the general deterioration of the environmental situation, climate change, pollution of the atmosphere and the aquatic environment, a problem has arisen associating with the effects on the human health of excessive ultraviolet irradiation. The global process of degradation of the Earth's ozone layer, one of the manifestations of which is the formation of "ozone holes", led to the disruption of the usual mode of natural UV radiation. The sun is the main source of optical radiation coming to the surface of the Earth from space. In quantitative terms, ultraviolet radiation...
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...Radiation proves to be one of the most devastating form of space weather. Solar energetic particle events and galactic cosmic rays are two types of radiation that can have adverse affects on a mission to the moon (WAS, 2018). Solar energetic particles come from solar flares or coronal mass ejections from the sun, and these events peak during the solar maximum (WAS, 18). Galactic cosmic rays are the most harmful, since they have accelerated to nearly the speed of light and come from outside of the solar system (NASA, 2012). The effects of radiation on humans can span from nausea, central nervous system damage, to long term risks of developing cancer due to damage of DNA (WAS, 2018). While radiation poses an imminent threat to space missions, there are ways to diminish its...
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...di-oxide is a natural constituent of atmosphere, but now, its concentration is increasing at an alarming rate. According to an estimate, CO2 level is expected to be doubled by 2030 A.D. The term ‘Green House Effect’ is also called as ‘Atmospheric Effect’, ‘Global Warming’ or ‘CO2 Problem’. Human activities are changing the composition as well as behaviour at an unprecedented rate. The pollutants form a wide range of human activities are increasing the global atmospheric concentration of certain heat trapping gases, which act like a blanket, trapping close to the surface that would otherwise escape through the atmosphere to the outer space. This process is known as ‘Green House Effect’. Green House is that body which allows the short wave length incoming solar radiation to come in, but does not allow the long wave outgoing terrestrial infra red radiation to escape. The progressive warming up of the earth’s surface due to blanketing effect of manmade CO 2 in the atmosphere is called ‘Green House Effect’. (Figure 1). The four major green house gases, which cause adverse effects are CO2, CH4, N2O and CFC’s. Among these CO2 is the most common and important green house gas. In addition, ozone and SO2 are also act as serious pollutants in causing global warming. Green House Effect Under normal concentrations of CO2, the temperature of the earth’s surface is maintained by the energy balance of the sun’s rays that strike the planet and the heat is radiated back into the outer space...
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...EXAMINATION OF THE MOUTH AND OTHER RELEVANT STRUCTURES A thorough case history and clinical examination are mandatory on the child’s first visit to the dentist and at the start of every new treatment period. KNOW YOUR PATIENT * Who is taking care of the child? * Who is with him today? * Is the child attending school? * Who referred the patient? * Where does the child live? * Important factors to be addressed during the child’s initial dental visit (3-6) * Limited existing health history * No clinical baseline data * Behavioral unknowns * A primary dental occlusion with limited predictive value * Preventive needs that must be assessed A thorough case history and clinical examination of the child patient is important in order to: * Establish good contact with and knowledge of the child and parent * Decide on prescriptions of radiographic and laboratory examinations * Identify possible signs of general conditions and diseases * Arrive at a proper diagnosis and appropriate treatment plan CASE HISTORY Case history in children, especially young children has to be taken through another person, the parent. This has 2 important implications: 1. The information obtained from the accompanying person may not necessarily reflect the situation of the child. 2. The dentist may tend to forget to communicate with the child, which occasionally leads the child to feel that he is being neglected by the dentist. CASE HISTORY ...
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...science, public health, sanitary engineering etc. In broader sense, it is the study of the sources, reactions, transport, effect and fate of chemical species in the air, water and soil and the effect of human activity upon these. Pollutant: A substance present in nature, in greater than natural abundance due to human activity, which ultimately has a detrimental effect on the environment and therefrom on living organisms and mankind. Examples are- lead, mercury, sulphur dioxide, carbon monoxide, etc. Contaminant: A material which does not occur in nature, but is introduced by human activity into the environment, affecting its composition. A contaminant is classified as a pollutant when it exerts a detrimental effect. Example- chlorine gas Types of Pollution Air Causes of air pollution: * motor vehicle exhaust * power stations * car manufacturing * fertilizer factories * demolishing buildings * solvent evaporation * volcanic eruption * building roads * forest fires Effect of air pollution: Global warming, acid rain, smog, ozone depletion are some effects of air pollution Water Causes of water pollution: * man-made chemicals used in farming * heavy metals * waste from factories * sediment from the river bed * air pollution * thermal (heat) pollution * soil pollution from rubbish dumps Effects of water pollution: The water in the earth’s biosphere is used and reused again and again by all living things Soil ...
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...RESEARCH ARTICLE EEG Changes Due to Experimentally Induced 3G Mobile Phone Radiation Suzanne Roggeveen1*, Jim van Os1,2, Wolfgang Viechtbauer1, Richel Lousberg1 1 Department of Psychiatry and Psychology, Maastricht University, Maastricht, The Netherlands, 2 King’s College London, King’s Health Partners, Department of Psychosis Studies, Institute of Psychiatry, London, United Kingdom * s.roggeveen@maastrichtuniversity.nl Abstract OPEN ACCESS Citation: Roggeveen S, van Os J, Viechtbauer W, Lousberg R (2015) EEG Changes Due to Experimentally Induced 3G Mobile Phone Radiation. PLoS ONE 10(6): e0129496. doi:10.1371/journal. pone.0129496 Academic Editor: Suminori Akiba, Kagoshima University Graduate School of Medical and Dental Sciences, JAPAN Received: September 24, 2014 Accepted: May 8, 2015 Published: June 8, 2015 Copyright: © 2015 Roggeveen et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Data Availability Statement: All relevant data are within the paper and its Supporting Information files. Funding: The authors received no specific funding for this work. Competing Interests: Suzanne Roggeveen has read the journal’s policy and the authors have the following conflict: Jim van Os is a PLOS ONE Editorial Board member. This does not alter the authors’...
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...P. K. Muana 3 January 2012 “Radiation and Cancer: The Connection between Cell Phone Use and Brain Cancer” According to a Baltimore neurologist, Christopher J. Newman, Motorola is the cause a life frightening tumor that has developed overtime in his brain. Newman sues Motorola for “a direct and proximate result of the defective and unreasonably dangerous condition of the relevant products” (Parascandola). The court system and scientist are feuding on the matter of using scientific data as evidence in court cases. The courts argue whether or not the data is applicable and reliable. Hence, the association of cellular phone radiation and brain cancer is still under dispute on whether there is a correlation in between the two. Worldwide there are over 4.3 billion cell phone users (web). This substantial number of cell phone users also causes generous amount of radiation to be generated. The radiation that is discharged through these devices is to as radio frequency (RF) energy. The measure of RF energy that is taken in by users is known as its Specific Absorption Rate or SAR. SAR is what researchers use to compare radiation given off by cell phones to cancerous tumors. Scientist research the amount of SAR that is exposed in different mobile phone models. For a phone to pass the Federal Communication Commission its SAR must be less than 1.6 W/kg (web). Researchers from CNET in 2007 did a study to show the quantity of radiation given off by various cell phone models...
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...Introduction Perhaps the most dangerous, damaging form of pollution facing developing countries every minute of every day is invisible, soundless, and cannot be touched or felt. It is electromagnetic field radiation (EMF) and it is emanating from virtually every single electrical appliance, computer, electric wire, TV, radio, microwaves and especially high voltage lines (overhead and buried) which are carrying current. Electric fields are measured in units of volts per meter or V/m. Magnetic fields are measured in milli-Gauss or mG. The field is always strongest near the source and diminishes as you move away from the source. These energies have the ability to influence particles at great distances. For example, the radiation from a radio tower influences the atoms within a distant radio antenna, allowing it to pick up the signal. Despite the many wonderful conveniences of electrical technology, the effects of EMF on biological tissue remains the most controversial aspect of the EMF issue with virtually all scientists agreeing that more research is necessary to determine safe or dangerous levels. Iron, necessary for healthy blood and stored in the brain, is highly effected by EMF. The permeability of the cell membrane of our nerves, blood vessels, skin, and other organs is effected. The intricate DNA of the chromosomes has been shown to be effected by EMFs as well. In fact, throughout our bodies, every biochemical process involves precisely choreographed movement...
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...out as the best and most efficient method of treating cancer patients. It solely uses protons rather than x-rays towards the treatment of cancer. These protons are released at high energy; at high energy protons have a high likelihood of destroying cancer. Some doctors use this therapy alone whereas others combine it with other therapies like chemotherapy, radiation therapy, immunotherapy, and surgery. It is most preferred for tumors that have not spread as well as for tumors near vital body organs like the spinal cord, the brain, and near the eye (Poludniowski, Allinson, & Evans, 2015). It is also recommended for treating tumors in children since it has a low likelihood of damaging healthy developing tissues. How Proton Therapy is beneficial compared to alternative treatments Unlike, x-rays, this therapy does not expose the body to radiation dose beyond the tumor. X-rays continually deposit radiation doses as the exit the body of the patient. This is a clear indication that x-rays have quite detrimental effects on the body; it has a high likelihood of damaging nearby healthy tissues hence causing several side effects. In other words, proton therapy plays an immense role in targeting a patient tumor in a precise manner; thus, reducing damage to any healthy tissue nears the tumor. Hence, it is much more accurate and precise as compared to any other forms of...
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