A phase transition from liquid state to gas state, which is affected by Raoult's law. It can be accomplished by fractional distillation.
A silver metallic element that exists as a liquid at room temperature. It has the atomic symbol Hg (from hydrargyrum, liquid silver), atomic number 80, and atomic weight 200.59. Mercury is used in many industrial applications and its salts have been employed therapeutically as purgatives, antisyphilitics, disinfectants, and astringents. It can be absorbed through the skin and mucous membranes which leads to MERCURY POISONING. Because of its toxicity, the clinical use of mercury and mercurials is diminishing.
Stable mercury atoms that have the same atomic number as the element mercury, but differ in atomic weight. Hg-196, 198-201, and 204 are stable mercury isotopes.
An order of fish with 26 families and over 3,000 species. This order includes the families CYPRINIDAE (minnows and CARPS), Cobitidae (loaches), and Catostomidae (suckers).
Mercury chloride (HgCl2). A highly toxic compound that volatizes slightly at ordinary temperature and appreciably at 100 degrees C. It is corrosive to mucous membranes and used as a topical antiseptic and disinfectant.
Accumulations of solid or liquid animal excreta usually from stables and barnyards with or without litter material. Its chief application is as a fertilizer. (From Webster's 3d ed)
Removal of ENVIRONMENTAL POLLUTANTS or contaminants for the general protection of the environment. This is accomplished by various chemical, biological, and bulk movement methods, in conjunction with ENVIRONMENTAL MONITORING.
A genus of gram-negative, rod-shaped bacteria that derives energy from the oxidation of one or more reduced sulfur compounds. Many former species have been reclassified to other classes of PROTEOBACTERIA.
A highly poisonous compound that is an inhibitor of many metabolic processes and is used as a test reagent for the function of chemoreceptors. It is also used in many industrial processes.
Radioactive air pollution refers to the presence and circulation of radioactive particles or gases in the atmosphere, originating from human activities such as nuclear power plant accidents, nuclear weapons testing, or improper disposal of radioactive waste, which can pose significant health risks to living organisms due to ionizing radiation exposure.
Contamination of the air, bodies of water, or land with substances that are harmful to human health and the environment.
A colorless alkaline gas. It is formed in the body during decomposition of organic materials during a large number of metabolically important reactions. Note that the aqueous form of ammonia is referred to as AMMONIUM HYDROXIDE.
The mixture of gases present in the earth's atmosphere consisting of oxygen, nitrogen, carbon dioxide, and small amounts of other gases.
Elimination of ENVIRONMENTAL POLLUTANTS; PESTICIDES and other waste using living organisms, usually involving intervention of environmental or sanitation engineers.
Chemical compounds which pollute the water of rivers, streams, lakes, the sea, reservoirs, or other bodies of water.
An element with the atomic symbol N, atomic number 7, and atomic weight [14.00643; 14.00728]. Nitrogen exists as a diatomic gas and makes up about 78% of the earth's atmosphere by volume. It is a constituent of proteins and nucleic acids and found in all living cells.
A plant genus of the family Cruciferae. It contains many species and cultivars used as food including cabbage, cauliflower, broccoli, Brussel sprouts, kale, collard greens, MUSTARD PLANT; (B. alba, B. junica, and B. nigra), turnips (BRASSICA NAPUS) and rapeseed (BRASSICA RAPA).
An element with the atomic symbol Se, atomic number 34, and atomic weight 78.96. It is an essential micronutrient for mammals and other animals but is toxic in large amounts. Selenium protects intracellular structures against oxidative damage. It is an essential component of GLUTATHIONE PEROXIDASE.
The presence of bacteria, viruses, and fungi in water. This term is not restricted to pathogenic organisms.
A compound formed in the liver from ammonia produced by the deamination of amino acids. It is the principal end product of protein catabolism and constitutes about one half of the total urinary solids.
The class of all enzymes catalyzing oxidoreduction reactions. The substrate that is oxidized is regarded as a hydrogen donor. The systematic name is based on donor:acceptor oxidoreductase. The recommended name will be dehydrogenase, wherever this is possible; as an alternative, reductase can be used. Oxidase is only used in cases where O2 is the acceptor. (Enzyme Nomenclature, 1992, p9)
The ability of microorganisms, especially bacteria, to resist or to become tolerant to chemotherapeutic agents, antimicrobial agents, or antibiotics. This resistance may be acquired through gene mutation or foreign DNA in transmissible plasmids (R FACTORS).

Exposure of medical personnel to methylmethacrylate vapor during percutaneous vertebroplasty. (1/834)

The occupational exposure to methylmethacrylate (MMA) vapor during percutaneous vertebroplasty was determined. During five vertebroplasty procedures, air-sampling pumps were attached to medical personnel. MMA vapor levels in the samples were then quantified using gas chromatography. The samples collected yielded MMA vapor levels of less than five parts per million (ppm). The MMA vapor concentrations measured were well below the recommended maximum exposure of 100 ppm over the course of an 8-hour workday.  (+info)

Characterization of inhaled alpha-methylstyrene vapor toxicity for B6C3F1 mice and F344 rats. (2/834)

alpha-Methylstyrene (AMS) is a chemical intermediate used in the synthesis of specialty polymers and copolymers. Inhalation studies of AMS were conducted because of the lack of toxicity data and the structural similarity of AMS to styrene, a toxic and potentially carcinogenic chemical. Male and female B6C3F1 mice were exposed to 0, 600, 800, or 1000 ppm AMS 6 h/day, 5 days/week, for 12 days. After 1 exposure, 21% (5/24) of female mice were found dead in the 1000-ppm group, 56% (10/18) in the 800-ppm group, and 6% (1/18) in the 600-ppm concentration group. After 12 exposures, relative liver weights were significantly increased and relative spleen weights were significantly decreased in both male and female mice at all concentrations. No microscopic treatment-related lesions were observed. A decrease in hepatic glutathione (GSH) was associated with AMS exposure for 1 and 5 days. Male and female F344 rats were exposed to 0, 600 or 1000 ppm AMS for 12 days. No mortality or sedation occurred in AMS-exposed rats. Relative liver weights were significantly increased in both males and females after 12 exposures to 600 or 1000 ppm. An increased hyaline droplet accumulation was detected in male rats in both concentration groups; no significant microscopic lesions were observed in other tissues examined. Exposure of male and female F344 rats and male NBR rats to 0, 125, 250 or 500 ppm AMS, 6 h/day for 9 days resulted in increased accumulation of hyaline droplets in the renal tubules of male F344 rats in the 250 and 500 ppm concentration groups. Although AMS and styrene are structurally very similar, AMS was considerably less toxic for mice and more toxic for male rats than styrene.  (+info)

Quantitative analysis of styrene monomer in polystyrene and foods including some preliminary studies of the uptake and pharmacodynamics of the monomer in rats. (3/834)

A variety of food containers, drinking cups and cutlery, fabricated from polystyrene (PS) or polystyrene-related plastic, were analyzed for their styrene monomer content. Samples of yogurt, packaged in PS cups, were similarly analyzed and the leaching of styrene monomer from PS containers by some food simulants was also determined. Blood level studies with rats, dosed with styrene monomer by various routes, illustrated uptake phenomena that were dependent on the dose and route of administration and were also affected by the vehicle used to convey the styrene monomer.  (+info)

Dose-dependent fate of vinyl chloride and its possible relationship to oncogenicity in rats. (4/834)

Studies on the fate of 14C-labeled vinyl chloride (VC) following oral administration and inhalation exposure in rats demonstrated that the disposition of VC in the body is a function of the dose. More importantly, from the data available, it appears that a correlation exists between doses of VC which cause tumors and those that saturate metabolic or detoxifying pathways. Additional studies characterized the depression of liver non-protein sulfhydryl content (primarily GSH) with the duration and concentration of exposure to VC. The results of these investigations indicate that statistical projections utilizing data collected from rats exposed to high doses of VC are invalid for predicting the hazard of low level exposure, because such projections violate a priori assumption that the dynamics governing the fate of VC in the body are unaltered.  (+info)

Health aspects of the curing of synthetic rubbers. (5/834)

A commonly used tread rubber formulation was cured in the laboratory under conditions simulating vulcanization in the Bag-O-Matic press. Volatile emissions were collected on charcoal and analyzed by combined GC-mass spectrometry. The compounds identified were either contaminants present in the raw material or reaction products. Some of these compounds were also identified in charcoal tube samples collected in the atmosphere of the industrial operations. Estimates based on the loss of weight of rubber during curing were used to predict airborne concentrations and compared to the concentrations actually found. The literature of the toxicity of raw materials and effluents was reviewed, and no acute or chronic toxicological effects would be anticipated. Information concerning potential carcinogenicity was not available and could not be evaluated.  (+info)

Transurethral prostate vaporization using an oval electrode in 82 cases of benign prostatic hyperplasia. (6/834)

OBJECTIVE: To present our initial experience in transurethral vaporization of the prostate (TVP) using an oval electrode for the treatment of benign prostatic hyperplasia (BPH). METHODS: A total of 82 patients underwent TVP procedures with the oval electrode. The newly designed oval-shaped electrode can work with a High Frequency Electrosurgery Unit. Prostate gland tissue was vaporized through an Fr 24 percutaneous nephroscope transurethrally. The operation procedure was similar to transurethral resection of the prostate (TURP) or transurethral laser prostatectomy (TULP). Power setting ranged from 240 W to 320 W. Local vaporization temperature reached 120 degrees C. RESULTS: Urination was recovered in all 82 patients after TVP. Mean post-treatment International Prostate Symptom Score (I-PSS) reduced from 27.10 to 5.05; mean bladder residual urine volume dropped from 147.71 ml to 33.2 ml; and mean urine flow rate (MFR) increased from 4.45 ml/s to 14.57 ml/s (P < 0.01). The initial results of short-term follow-up were excellent. CONCLUSIONS: TVP with the oval electrode is easy to perform and causes less hemorrhage and few complications. It especially benefits elderly and/or critically-ill patients. We believe that TVP with our oval electrode is feasible with low risk.  (+info)

Estimation of the dermal absorption of m-xylene vapor in humans using breath sampling and physiologically based pharmacokinetic analysis. (7/834)

A physiologically-based pharmacokinetic model, containing a skin compartment, was derived and used to simulate experimentally determined exposure to m-xylene, using human volunteers exposed under controlled conditions. Biological monitoring was conducted by sampling, in exhaled alveolar air and blood, m-xylene and urinary methyl hippuric acid concentrations. The dermal absorption of m-xylene vapor was successfully and conveniently studied using a breath sampling technique, and the contribution to m-xylene body burden from the dermal route of exposure was estimated to be 1.8%. The model was used to investigate the protection afforded by an air-fed, half-face mask. By iteratively changing the dermal exposure concentration, it was possible to predict the ambient concentration that was required to deliver the observed urinary excretion of methylhippuric acid, during and following inhalation exposure to 50 ppm m-xylene vapor. This latter extrapolation demonstrates how physiologically-based pharmacokinetic modeling can be applied in a practical and occupationally relevant way, and permitted a further step not possible with biological monitoring alone. The ability of the model to extrapolate an ambient exposure concentration was dependent upon human metabolism data, thereby demonstrating the mechanistic toxicological basis of model output. The methyl hydroxylation of m-xylene is catalyzed by the hepatic mixed function oxidase enzyme, cytochrome P450 2E1 and is active in the occupationally relevant, (<100 ppm) exposure range of m-xylene. The use of a scaled-up in vitro maximum rate of metabolism (Vmaxc) in the model also demonstrates the increasingly valuable potential utility of biokinetic data determined using alternative, non-animal methods in human chemical-risk assessment.  (+info)

Environmental exposure to volatile organic compounds among workers in Mexico City as assessed by personal monitors and blood concentrations. (8/834)

Benzene, an important component in gasoline, is a widely distributed environmental contaminant that has been linked to known health effects in animals and humans, including leukemia. In Mexico City, environmental benzene levels, which may be elevated because of the heavy traffic and the poor emission control devices of older vehicles, may pose a health risk to the population. To assess the potential risk, portable passive monitors and blood concentrations were used to survey three different occupational groups in Mexico City. Passive monitors measured the personal exposure of 45 workers to benzene, ethylbenzene, toluene, o-xylene and m-/p-xylene during a work shift. Blood concentrations of the above volatile organic compounds (VOCs), methyl tert-butyl ether, and styrene were measured at the beginning and the end of a work shift. Passive monitors showed significantly higher (p > 0.0001) benzene exposure levels among service station attendants (median = 330 microg/m3; range 130-770) as compared to street vendors (median = 62 microg/m3; range 49-180) and office workers (median = 44 microg/m3, range 32-67). Baseline blood benzene levels (BBLs) for these groups were higher than those reported for similar populations from Western countries (median = 0.63 microg/L, n = 24 for service station attendants; median = 0.30 microg/L, n = 6 for street vendors; and median = 0.17 microgr;g/L, n = 7 for office workers). Nonsmoking office workers who were nonoccupationally exposed to VOCs had BBLs that were more than five times higher than those observed in a nonsmoking U.S. population. BBLs of participants did not increase during the work shift, suggesting that because the participants were chronically exposed to benzene, complex pharmacokinetic mechanisms were involved. Our results highlight the need for more complete studies to assess the potential benefits of setting environmental standards for benzene and other VOCs in Mexico.  (+info)

Volatilization, in the context of pharmacology and medicine, refers to the process by which a substance (usually a medication or drug) transforms into a vapor state at room temperature or upon heating. This change in physical state allows the substance to evaporate and be transferred into the air, potentially leading to inhalation exposure.

In some medical applications, volatilization is used intentionally, such as with essential oils for aromatherapy or topical treatments that utilize a vapor action. However, it can also pose concerns when volatile substances are unintentionally released into the air, potentially leading to indoor air quality issues or exposure risks.

It's important to note that in clinical settings, volatilization is not typically used as a route of administration for medications, as other methods such as oral, intravenous, or inhalation via nebulizers are more common and controlled.

In the context of medicine, Mercury does not have a specific medical definition. However, it may refer to:

1. A heavy, silvery-white metal that is liquid at room temperature. It has been used in various medical and dental applications, such as therapeutic remedies (now largely discontinued) and dental amalgam fillings. Its use in dental fillings has become controversial due to concerns about its potential toxicity.
2. In microbiology, Mercury is the name of a bacterial genus that includes the pathogenic species Mercury deserti and Mercury avium. These bacteria can cause infections in humans and animals.

It's important to note that when referring to the planet or the use of mercury in astrology, these are not related to medical definitions.

Mercury isotopes refer to variants of the chemical element mercury (Hg) that have different numbers of neutrons in their atomic nuclei. This means that while all mercury isotopes have 80 protons in their nucleus, they can have different numbers of neutrons, ranging from 120 to 124 or more.

The most common and stable mercury isotope is Hg-202, which has 80 protons and 122 neutrons. However, there are several other mercury isotopes that occur naturally in trace amounts, including Hg-196, Hg-198, Hg-199, Hg-200, and Hg-204.

Mercury isotopes can also be produced artificially through various nuclear reactions. These isotopes may have different physical and chemical properties than the more common mercury isotopes, which can make them useful for a variety of applications, such as in medical imaging or environmental monitoring. However, some mercury isotopes are radioactive and can be hazardous to handle or dispose of improperly.

Cypriniformes is an order of freshwater fish that includes carps, minnows, and loaches. These fish are characterized by the presence of a single pair of barbels near their mouths and the absence of teeth on their jaws. They are found primarily in North America, Europe, and Asia. Some well-known examples of Cypriniformes include the common carp, goldfish, and zebrafish. These fish are often used as model organisms in scientific research due to their relatively small size, ease of breeding, and genetic similarity to humans.

Mercuric chloride, also known as corrosive sublimate, is defined medically as a white or colorless crystalline compound used historically as a topical antiseptic and caustic. It has been used in the treatment of various skin conditions such as warts, thrush, and some parasitic infestations. However, its use is limited nowadays due to its high toxicity and potential for serious side effects, including kidney damage, digestive problems, and nervous system disorders. It is classified as a hazardous substance and should be handled with care.

"Manure" is not a term typically used in medical definitions. However, it is commonly referred to in agriculture and horticulture. Manure is defined as organic matter, such as animal feces and urine, that is used as a fertilizer to enrich and amend the soil. It is often rich in nutrients like nitrogen, phosphorus, and potassium, which are essential for plant growth. While manure can be beneficial for agriculture and gardening, it can also pose risks to human health if not handled properly due to the potential presence of pathogens and other harmful substances.

Environmental remediation is the process of treating, removing, or containing contamination from environmental media such as soil, groundwater, sediment, or surface water for the purpose of reducing the impact on human health and the environment. The goal of environmental remediation is to return the contaminated area to its original state, or to a state that is safe for use and poses no significant risk to human health or the environment. This process often involves various techniques such as excavation, soil washing, bioremediation, chemical treatment, and thermal treatment. The specific method used depends on the type and extent of contamination, as well as site-specific conditions.

Thiobacillus is a genus of gram-negative, rod-shaped bacteria that are capable of oxidizing inorganic sulfur compounds and sulfides to produce sulfuric acid. These bacteria play a significant role in the biogeochemical cycles of sulfur and carbon, particularly in environments like soil, water, and sediments. They are widely distributed in nature and can be found in various habitats such as acid mine drainage, sewage treatment plants, and even in the human respiratory system. Some species of Thiobacillus have been used in industrial applications for the bioremediation of heavy metal-contaminated soils and wastewater treatment. However, they can also contribute to the corrosion of metals and concrete structures due to their acid production.

Sodium cyanide is a highly toxic chemical compound with the formula NaCN. It is a white solid that is readily soluble in water, and it has a bitter, almond-like odor that some people can detect. Sodium cyanide is used in various industrial processes, including metal cleaning and electroplating, but it is perhaps best known as a poison.

Cyanide ions (CN-) are extremely toxic because they bind to the ferric iron (Fe3+) in cytochrome c oxidase, a crucial enzyme in the mitochondria that is responsible for cellular respiration and energy production. When cyanide ions bind to this enzyme, it becomes unable to function, leading to a rapid depletion of ATP (adenosine triphosphate) and an accumulation of lactic acid, which can cause metabolic acidosis, coma, and death within minutes to hours.

It is important to note that sodium cyanide should be handled with extreme care and only by trained professionals who are familiar with its hazards and proper safety protocols. Exposure to this compound can cause severe health effects, including respiratory failure, convulsions, and cardiac arrest.

Radioactive air pollution refers to the presence of radioactive particles or radionuclides in the air. These substances emit ionizing radiation, which can be harmful to human health and the environment. Radioactive air pollution can come from a variety of sources, including nuclear power plants, nuclear weapons testing, industrial activities, and natural processes such as the decay of radon gas.

Exposure to radioactive air pollution can increase the risk of developing cancer and other diseases, particularly in cases of prolonged or high-level exposure. It is important to monitor and regulate radioactive air pollution to protect public health and ensure compliance with safety standards.

Environmental pollution is the introduction or presence of harmful substances, energies, or objects in the environment that can cause adverse effects on living organisms and ecosystems. These pollutants can be in the form of chemical, physical, or biological agents that contaminate air, water, soil, or noise levels, exceeding safe limits established by environmental regulations.

Examples of environmental pollution include:

1. Air pollution: The presence of harmful substances such as particulate matter, sulfur dioxide, nitrogen oxides, and volatile organic compounds (VOCs) in the air that can cause respiratory and other health problems.
2. Water pollution: Contamination of water sources with chemicals, heavy metals, pathogens, or other pollutants that can harm aquatic life and make the water unsafe for human consumption or recreational use.
3. Soil pollution: The presence of harmful substances such as heavy metals, pesticides, and industrial waste in soil that can reduce soil fertility, contaminate crops, and pose a risk to human health.
4. Noise pollution: Excessive noise levels from transportation, industrial activities, or other sources that can cause stress, sleep disturbances, and hearing loss in humans and animals.
5. Light pollution: The excessive use of artificial light that can disrupt ecosystems, affect human circadian rhythms, and contribute to energy waste.

Environmental pollution is a significant global health issue that requires urgent attention and action from governments, industries, and individuals to reduce pollutant emissions, promote sustainable practices, and protect the environment for future generations.

Ammonia is a colorless, pungent-smelling gas with the chemical formula NH3. It is a compound of nitrogen and hydrogen and is a basic compound, meaning it has a pH greater than 7. Ammonia is naturally found in the environment and is produced by the breakdown of organic matter, such as animal waste and decomposing plants. In the medical field, ammonia is most commonly discussed in relation to its role in human metabolism and its potential toxicity.

In the body, ammonia is produced as a byproduct of protein metabolism and is typically converted to urea in the liver and excreted in the urine. However, if the liver is not functioning properly or if there is an excess of protein in the diet, ammonia can accumulate in the blood and cause a condition called hyperammonemia. Hyperammonemia can lead to serious neurological symptoms, such as confusion, seizures, and coma, and is treated by lowering the level of ammonia in the blood through medications, dietary changes, and dialysis.

In medical terms, 'air' is defined as the mixture of gases that make up the Earth's atmosphere. It primarily consists of nitrogen (78%), oxygen (21%), and small amounts of other gases such as argon, carbon dioxide, and trace amounts of neon, helium, and methane.

Air is essential for human life, as it provides the oxygen that our bodies need to produce energy through respiration. We inhale air into our lungs, where oxygen is absorbed into the bloodstream and transported to cells throughout the body. At the same time, carbon dioxide, a waste product of cellular metabolism, is exhaled out of the body through the lungs and back into the atmosphere.

In addition to its role in respiration, air also plays a critical role in regulating the Earth's climate and weather patterns, as well as serving as a medium for sound waves and other forms of energy transfer.

Environmental biodegradation is the breakdown of materials, especially man-made substances such as plastics and industrial chemicals, by microorganisms such as bacteria and fungi in order to use them as a source of energy or nutrients. This process occurs naturally in the environment and helps to break down organic matter into simpler compounds that can be more easily absorbed and assimilated by living organisms.

Biodegradation in the environment is influenced by various factors, including the chemical composition of the substance being degraded, the environmental conditions (such as temperature, moisture, and pH), and the type and abundance of microorganisms present. Some substances are more easily biodegraded than others, and some may even be resistant to biodegradation altogether.

Biodegradation is an important process for maintaining the health and balance of ecosystems, as it helps to prevent the accumulation of harmful substances in the environment. However, some man-made substances, such as certain types of plastics and industrial chemicals, may persist in the environment for long periods of time due to their resistance to biodegradation, leading to negative impacts on wildlife and ecosystems.

In recent years, there has been increasing interest in developing biodegradable materials that can break down more easily in the environment as a way to reduce waste and minimize environmental harm. These efforts have led to the development of various biodegradable plastics, coatings, and other materials that are designed to degrade under specific environmental conditions.

Chemical water pollutants refer to harmful chemicals or substances that contaminate bodies of water, making them unsafe for human use and harmful to aquatic life. These pollutants can come from various sources, including industrial and agricultural runoff, sewage and wastewater, oil spills, and improper disposal of hazardous materials.

Examples of chemical water pollutants include heavy metals (such as lead, mercury, and cadmium), pesticides and herbicides, volatile organic compounds (VOCs), polychlorinated biphenyls (PCBs), and petroleum products. These chemicals can have toxic effects on aquatic organisms, disrupt ecosystems, and pose risks to human health through exposure or consumption.

Regulations and standards are in place to monitor and limit the levels of chemical pollutants in water sources, with the aim of protecting public health and the environment.

Nitrogen is not typically referred to as a medical term, but it is an element that is crucial to medicine and human life.

In a medical context, nitrogen is often mentioned in relation to gas analysis, respiratory therapy, or medical gases. Nitrogen (N) is a colorless, odorless, and nonreactive gas that makes up about 78% of the Earth's atmosphere. It is an essential element for various biological processes, such as the growth and maintenance of organisms, because it is a key component of amino acids, nucleic acids, and other organic compounds.

In some medical applications, nitrogen is used to displace oxygen in a mixture to create a controlled environment with reduced oxygen levels (hypoxic conditions) for therapeutic purposes, such as in certain types of hyperbaric chambers. Additionally, nitrogen gas is sometimes used in cryotherapy, where extremely low temperatures are applied to tissues to reduce pain, swelling, and inflammation.

However, it's important to note that breathing pure nitrogen can be dangerous, as it can lead to unconsciousness and even death due to lack of oxygen (asphyxiation) within minutes.

'Brassica' is a term used in botanical nomenclature, specifically within the family Brassicaceae. It refers to a genus of plants that includes various vegetables such as broccoli, cabbage, cauliflower, kale, and mustard greens. These plants are known for their nutritional value and health benefits. They contain glucosinolates, which have been studied for their potential anti-cancer properties. However, it is not a medical term per se, but rather a taxonomic category used in the biological sciences.

Selenium is a trace element that is essential for the proper functioning of the human body. According to the medical definitions provided by the National Institutes of Health (NIH), selenium is a component of several major metabolic pathways, including thyroid hormone metabolism, antioxidant defense systems, and immune function.

Selenium is found in a variety of foods, including nuts (particularly Brazil nuts), cereals, fish, and meat. It exists in several forms, with selenomethionine being the most common form found in food. Other forms include selenocysteine, which is incorporated into proteins, and selenite and selenate, which are inorganic forms of selenium.

The recommended dietary allowance (RDA) for selenium is 55 micrograms per day for adults. While selenium deficiency is rare, chronic selenium deficiency can lead to conditions such as Keshan disease, a type of cardiomyopathy, and Kaschin-Beck disease, which affects the bones and joints.

It's important to note that while selenium is essential for health, excessive intake can be harmful. High levels of selenium can cause symptoms such as nausea, vomiting, hair loss, and neurological damage. The tolerable upper intake level (UL) for selenium is 400 micrograms per day for adults.

Water microbiology is not a formal medical term, but rather a branch of microbiology that deals with the study of microorganisms found in water. It involves the identification, enumeration, and characterization of bacteria, viruses, parasites, and other microscopic organisms present in water sources such as lakes, rivers, oceans, groundwater, drinking water, and wastewater.

In a medical context, water microbiology is relevant to public health because it helps to assess the safety of water supplies for human consumption and recreational activities. It also plays a critical role in understanding and preventing waterborne diseases caused by pathogenic microorganisms that can lead to illnesses such as diarrhea, skin infections, and respiratory problems.

Water microbiologists use various techniques to study water microorganisms, including culturing, microscopy, genetic analysis, and biochemical tests. They also investigate the ecology of these organisms, their interactions with other species, and their response to environmental factors such as temperature, pH, and nutrient availability.

Overall, water microbiology is a vital field that helps ensure the safety of our water resources and protects public health.

Urea is not a medical condition but it is a medically relevant substance. Here's the definition:

Urea is a colorless, odorless solid that is the primary nitrogen-containing compound in the urine of mammals. It is a normal metabolic end product that is excreted by the kidneys and is also used as a fertilizer and in various industrial applications. Chemically, urea is a carbamide, consisting of two amino groups (NH2) joined by a carbon atom and having a hydrogen atom and a hydroxyl group (OH) attached to the carbon atom. Urea is produced in the liver as an end product of protein metabolism and is then eliminated from the body by the kidneys through urination. Abnormal levels of urea in the blood, known as uremia, can indicate impaired kidney function or other medical conditions.

Oxidoreductases are a class of enzymes that catalyze oxidation-reduction reactions, which involve the transfer of electrons from one molecule (the reductant) to another (the oxidant). These enzymes play a crucial role in various biological processes, including energy production, metabolism, and detoxification.

The oxidoreductase-catalyzed reaction typically involves the donation of electrons from a reducing agent (donor) to an oxidizing agent (acceptor), often through the transfer of hydrogen atoms or hydride ions. The enzyme itself does not undergo any permanent chemical change during this process, but rather acts as a catalyst to lower the activation energy required for the reaction to occur.

Oxidoreductases are classified and named based on the type of electron donor or acceptor involved in the reaction. For example, oxidoreductases that act on the CH-OH group of donors are called dehydrogenases, while those that act on the aldehyde or ketone groups are called oxidases. Other examples include reductases, peroxidases, and catalases.

Understanding the function and regulation of oxidoreductases is important for understanding various physiological processes and developing therapeutic strategies for diseases associated with impaired redox homeostasis, such as cancer, neurodegenerative disorders, and cardiovascular disease.

Microbial drug resistance is a significant medical issue that refers to the ability of microorganisms (such as bacteria, viruses, fungi, or parasites) to withstand or survive exposure to drugs or medications designed to kill them or limit their growth. This phenomenon has become a major global health concern, particularly in the context of bacterial infections, where it is also known as antibiotic resistance.

Drug resistance arises due to genetic changes in microorganisms that enable them to modify or bypass the effects of antimicrobial agents. These genetic alterations can be caused by mutations or the acquisition of resistance genes through horizontal gene transfer. The resistant microbes then replicate and multiply, forming populations that are increasingly difficult to eradicate with conventional treatments.

The consequences of drug-resistant infections include increased morbidity, mortality, healthcare costs, and the potential for widespread outbreaks. Factors contributing to the emergence and spread of microbial drug resistance include the overuse or misuse of antimicrobials, poor infection control practices, and inadequate surveillance systems.

To address this challenge, it is crucial to promote prudent antibiotic use, strengthen infection prevention and control measures, develop new antimicrobial agents, and invest in research to better understand the mechanisms underlying drug resistance.

"Reactive Flash Volatilization of Fluid Fuels" "Flash volatilization: a new biomass-to-liquids process". Biopact. 2006-11-04. ... Reactive flash volatilization (RFV) is a chemical process that rapidly converts nonvolatile solids and liquids to volatile ... A publication in the scientific journal Green Chemistry demonstrated that the process of reactive flash volatilization can be ... The first demonstration of reactive flash volatilization occurred by a series of experimental steps: The researchers start with ...
Generally speaking, volatilization will be lower when urea is applied during the wetter and cooler conditions that generally ... Ammonia volatilization reduces the economic efficiency of agricultural cropping systems. Either yield will be reduced or ... The soil's pH also has a strong effect on the amount of volatilization. Specifically, highly alkaline soils (pH~8.2 or higher) ... More urease results in greater hydrolysis of urea and ammonia volatilization, particularly if urea fails to move into the soil ...
Volatilization is the process whereby a dissolved sample is vaporised. In atomic spectroscopy this is usually a two-step ... Herbicide volatilisation refers to evaporation or sublimation of a volatile herbicide. The effect of gaseous chemical is lost ... 2,4-D and dicamba are commonly used chemicals that are known to be subject to volatilisation but there are many others. ... Herbicides vary in their susceptibility to volatilisation. Prompt incorporation of the herbicide into the soil may reduce or ...
Adding vinegar also helps reduce nitrogen loss (via ammonia volatilization) during short-term storage. Freney, J. R., Simpson, ... J. R., & Denmead, O. T. (1981). AMMONIA VOLATILIZATION. Ecological Bulletins, 33, 291-302. https://www.jstor.org/stable/ ...
Incorporation and/or injection of urea and ammonium-containing fertilizers decreases ammonia volatilization because good soil ... and volatilization (or other gas exchanges). There can be potential interactions because of differences in nutrient pathways ... reducing volatilization losses when these fertilizers are surface applied; these losses can be meaningful in high-residue, ... ammonia volatilization; and denitrification. Nitrogen management aims to maximize the efficiency with which crops use applied N ...
Hulett, G. A.; Berger, H. W. (1904). "Volatilization of Platinum". Journal of the American Chemical Society. 26 (11): 1512-1515 ...
Cameron, A.G.W. (1985). "The partial volatilization of Mercury". Icarus. 64 (2): 285-294. Bibcode:1985Icar...64..285C. doi: ...
He was interred at the cimetière du Père-Lachaise (44th division). The Volatilization of Polonium, 1928. Radon action on the ... La Volatilisation du polonium Paul Bonét-Maury; Mme Curie, présidente du jury bibliotheques.mnhn.fr, accessed 19 August 2019 ...
In volatilization methods, removal of the analyte involves separation by heating or chemically decomposing a volatile sample at ... Volatilization methods can be either direct or indirect. Water eliminated in a quantitative manner from many inorganic ... Another direct volatilization method involves carbonates which generally decompose to release carbon dioxide when acids are ... "Section 3-2: Volatilization methods". January 8, 2017. Archived from the original on November 25, 2016. Retrieved January 8, ...
A final idea is using less urea and ammonium based fertilizers which are prone to volatilization into ammonia. Nitrogen cycle ... One suggested change is keeping manure and fertilizer in large storage tanks to prevent runoff and volatilization into the air ... 2013). Ammonia Volatilization [PowerPoint presentation]. Hermiston Agricultural Research and Extension Center, Oregon. https:// ...
doi:10.1016/0019-1035(88)90118-2. Cameron, Alastair G. W. (1985). "The partial volatilization of Mercury". Icarus. 64 (2): 285- ...
Alexander CA (2005). "Volatilization of urania under strongly oxidizing conditions". Journal of Nuclear Materials. 346 (2-3): ...
"Microbial participation in iodine volatilization from soils". Environmental Science & Technology. 37 (17): 3885-3890. Bibcode: ...
R. James, Ryan; G. McDonald, Jeffrey; Symonik, Daniel; Swackhamer, Deborah; A. Hites, Ronald (2001-08-10). "Volatilization of ...
... laquelle volatilisation a été effectuée au moyen des acides" [Observation of a remarkable volatilization of part of a type of ... Marggraf, Andreas Sigismun (1770). "Observation concernant une volatilisation remarquable d'une partie de l'espece de pierre, à ... stone to which one gives the name flosse, flüsse, flus-spaht, as well as that of hesperos; which volatilization was effected by ...
... laquelle volatilisation a été effectuée au moyen des acides" [Observation of a remarkable volatilization of part of a type of ... ISBN 978-0-935702-90-3. Marggraf, Andreas Sigismun (1770). "Observation concernant une volatilisation remarquable d'une partie ... stone to which one gives the name flosse, flüsse, flus-spaht, as well as that of hesperos; which volatilization was effected by ...
Gibon, Fénelon (10 November 1907). "Encore la volatilisation d'un milliard". Le Correspondant. Hillairet, Jacques (1963). ...
... claimants of the volatilization of savings in Novo Banco; defense of minority shareholders in the MasMovil group and the ...
Ammonia volatilisation occurs when ammonium reacts chemically with an alkaline soil, converting NH4+ to NH3. The application of ... All kinds of nitrogen losses, whether by leaching or volatilization, are responsible for a large part of aquifer pollution and ... Rao, Desiraju L.N. & Batra, Lalit (1983). "Ammonia volatilization from applied nitrogen in alkali soils" (PDF). Plant and Soil ... ammonium fertiliser to such a field can result in volatilisation losses of as much as 30 percent. ...
"Renewable Hydrogen from Nonvolatile Fuels by Reactive Flash Volatilization". Science. 314 (5800): 801-804. Bibcode:2006Sci... ... known for mentoring over a hundred graduate students and his work on millisecond reactors and reactive flash volatilization. ...
One way is through volatilization from rivers and lakes. Henry's law estimates that the volatilization half life from a model ...
"Rhizosphere Bacteria Enhance Selenium Accumulation and Volatilization by Indian mustard". Plant Physiology. 119 (2): 565-574. ...
Volatilization is the primary removal mechanism on most ERH sites. However, ERH can also be used to enhance other processes, ...
Herbicide volatilisation refers to evaporation or sublimation of a volatile herbicide. The effect of a gaseous chemical is lost ... 2,4-D and dicamba are commonly used chemicals that are known to be subject to volatilisation, but there are many others. The ... Herbicides vary in their susceptibility to volatilisation. Prompt incorporation of the herbicide into the soil may reduce or ... Wind, temperature, and humidity also affect the rate of volatilisation, with humidity reducing it. ...
Primary methods of endrin disappearance from soil are volatilization and photodecomposition. Under ultraviolet light, endrin ...
Effects of starch encapsulation on clomazone and atrazine movement in soil and clomazone volatilization. Weed Science. 43:445- ... Adsorption of the herbicide to soil solids slows degradation and volatilization. Encapsulation helps reduce volatility and ...
... by successive volatilization and condensation as early as 1981... Harrad, Stuart (6 December 2012). Persistent Organic ...
Pan, Baobao; Lam, Shu Kee; Mosier, Arvin; Luo, Yiqi; Chen, Deli (2016). "Ammonia Volatilization from Synthetic Fertilizers and ...
Pan B, Lam SK, Mosier A, Luo Y, Chen D (2016). "Ammonia Volatilization from Synthetic Fertilizers and its Mitigation Strategies ...
Pan, Baobao; Lam, Shu Kee; Mosier, Arvin; Luo, Yiqi; Chen, Deli (2016). "Ammonia Volatilization from Synthetic Fertilizers and ...
"Reactive Flash Volatilization of Fluid Fuels" "Flash volatilization: a new biomass-to-liquids process". Biopact. 2006-11-04. ... Reactive flash volatilization (RFV) is a chemical process that rapidly converts nonvolatile solids and liquids to volatile ... A publication in the scientific journal Green Chemistry demonstrated that the process of reactive flash volatilization can be ... The first demonstration of reactive flash volatilization occurred by a series of experimental steps: The researchers start with ...
... with some volatilization to the atmosphere (Oliver, 1984; Oliver and Carey, 1986). The half-lives for volatilization of ... Volatilization. In: Lyman, Reehl, and Rosenblatt, eds. Handbook of Chemical Properties Estimation Methods. McGraw-Hill Book Co ... The fate of tetrachlorobenzenes in the environment is governed by transport processes such as volatilization and adsorption, ...
Environ Sci Technol 34(5):915-917.Gan J, Yates SR, Ernst FF, Jury WA [2000]. Degradation and volatilization of the fumigant ...
Evaluation of ammonia volatilization losses by adjusted parameters of a logistic function Soil Use And Management. Vale, Marcos ... Patterns of ammonia volatilization losses provide details on behavior of the variable, details which can be used to develop and ... Thus, the purpose of this study was to evaluate the patterns of cumulative N losses from urea through ammonia volatilization in ... Univariate analysis showed that the parameters related to total N losses and rate of volatilization were more affected by soil ...
Volatilisation: Based on the vapour pressure of the substance (1.5·10-6Pa (20°C)), SymHelios® 1031 can safely be considered as ...
The deterministic as well as the probabilistic risk analyses in this study indicated that postspray volatilization in the ... We examined the significance of meteorology and postspray volatilization of methamidophos (an organophosphorus insecticide) in ...
Volatilization: The changing of a liquid into a vapor or a gas. ... It may also enter the environment through volatilization, ...
Optimum rates of surface-applied coal char decreased soil ammonia volatilization loss. Panday D, Mikha MM, Collins HP, Jin VL, ...
refers to the speed of the volatilization of the pheromone.. After the ants return to the starting point, send out the second ... 5) The volatilization of the pheromone {the pheromone will dissipate as time goes by}. ... Modify artificial ant colony, routing selection and pheromone volatilization to optimize the basic ant colony algorithm and ... namely the volatilization coefficient is 0.1. The Sink broadcasts Ant Packet query message every 10 seconds. Randomly choose 20 ...
Volatilization from Water: Henry LC: 8.15E-005 atm-m3/mole (estimated by Bond SAR Method) ...
VOLATILIZATION OF TRIFLURALIN, ATRAZINE, METOLACHLOR, CHLORPYRIFOS, A-ENDOSULFAN, AND B-ENDOSULFAN FROM FRESHLY TILLED SOIL - ( ...
The downside, however, is short volatilization, necessitating regular disinfections. While non-volatile metal-based antivirals ...
Different types of this method of analysis contain precipitation, volatilization and electro-analytical method. Several ...
... and volatilization called as phytovolatilization. ...
In aerobic soils the decrease was mainly due to volatilization and binding to the soil. In aerobic loam about 20% of the total ... radioactivity was lost by volatilization in 14 days, and in silt loam 35% in 21 days. In aerobic soil the main organo-soluble ...
Volatilization. Selenium volatilizes from soils at rates that are modified by temperature, moisture, time, season or year, ...
Amine Volatilization from Herbicide Salts: Implications for Herbicide Formulations and Atmospheric Chemistry. Sharkey, S.M., ...
Volatilisation is not an applicable endpoint for cobalt metal or cobalt salts. ...
... volatilization, and leaching. The uptake of N by crops is closely related to rootability conditions in the soil: higher root ...
Volatilisation as max % of applied dose lost. From plant surface. -. -. -. From soil surface. ...
Effect of Agrotain Treated Urea on Ammonia Volatilization in Kentucky Bluegrass the Columbia Basin ... Effect of Agrotain Treated Urea on Ammonia Volatilization in Kentucky Bluegrass the Columbia Basin ... Effect of Agrotain Treated Urea on Ammonia Volatilization in Kentucky Bluegrass the Columbia Basin ...
Volatilization and carryover of silica with the steam may cause hard, ... Volatilization and carryover of silica with the steam may cause hard, glassy siliceous deposits to form on turbine blades that ...
The liquid will remain on the slats, increasing the volatilisation. Grooved slats, to facilitate drainage, will result in lower ... it is unlikely to reduce the opportunity for ammonia volatilisation from the concrete surfaces. ... did not close properly or the slurry was not able to open the valve and so remained in the channels allowing volatilisation. ...
High-temperature Volatility. Grease made from low-viscosity base oils is at the highest risk of volatilization. At sufficiently ...
The properties of metallic technetium, solution chemistry, volatilization methods, extraction into organic solvents, ...
Houbraken M, van den Berg F, Butler Ellis CM, Dekeyser D, Nuyttens D, de Schampheleire M and Spanoghe P,2016:Volatilisation of ...
Smaller plumes are produced near the margins of active lava flows by explosive volatilization of the underlying or surrounding ...
Nitrogen fertilizer can be lost through volatilization, leaching, or denitrification depending on conditions. Farmers can adapt ...
... less fragmentation because the laser beams interaction with the sample leads to rapid heating and subsequent volatilization. ...
  • Optimum rates of surface-applied coal char decreased soil ammonia volatilization loss. (nih.gov)
  • RFV: Biomass + heat + Reactant + Catalyst → Gases + VOCs + Reactant + Catalyst → Products + Catalyst Reactive flash volatilization was demonstrated in 2006 in the journal Science by the high temperature (700-800 °C) conversion of soybean oil (triglycerides) and sugar (D-(+)-glucose) to synthesis gas (H2 + CO) and olefins (ethylene and propylene). (wikipedia.org)
  • however paramonochlorophenol was unable to exert antibacterial activity from the volatilization of its gases. (bvsalud.org)
  • 2002). Exposure continues from leaks from transformers and capacitors, volatilization of PCBs in cites, in buildings, from sewage, landfills and waste sites, and combustion of materials containing PCBs (Dyke et al. (who.int)
  • Chemicals (including disinfection byproducts) in drinking water or in recreational water that cause health effects either through water exposure or by volatilization leading to poor air quality are included. (cdc.gov)
  • We examined the significance of meteorology and postspray volatilization of methamidophos (an organophosphorus insecticide) in assessing potential inhalation risk to children in an agricultur al community. (cdc.gov)
  • The deterministic as well as the probabilistic risk analyses in this study indicated that postspray volatilization in the specific spray situation analyzed (methamidophos applied on potato fields in Eastern Washington) did not pose acute or subchronic risks as defined by the EPA. (cdc.gov)
  • Grease made from low-viscosity base oils is at the highest risk of volatilization. (machinerylubrication.com)
  • Nitrogen fertilizer can be lost through volatilization, leaching, or denitrification depending on conditions. (realagriculture.com)
  • The aim of the present study was to evaluate the antimicrobial effects of paramonochlorophenol and tricresol formalin using a new methodology to simulate the volatilization of these substances. (bvsalud.org)
  • 19. [Effect of Biochar and Chemical Fertilizer Mixture on Ammonia Volatilization and Phosphorus Fixation]. (nih.gov)
  • Leytem and Bjorneberg concluded that dairy farmers who use dairy manure to amend soils could best reduce ammonia emissions by using subsurface injection, and that immediately incorporating manure deep into the soils during its application can limit losses of manure nitrogen from ammonia volatilization. (phys.org)
  • An on-farm study lead by Montana State University Soil Scientist Richard Engel and funded by SARE has shed light on the urea fertilization practices that are most susceptible to nitrogen volatilization. (sare.org)
  • Noteworthy is 30-3-15's active role in reducing nitrogen loss, mitigating volatilization, and preventing nitrate leaching into groundwater. (tlhort.com)
  • The arrows show the movement of PCBs between the water and the air is dominated by volatilization. (nih.gov)
  • The neutral acids, however, have relatively high KAWs and volatilization from water has been demonstrated. (scipedia.com)
  • The extent of volatilization of PFCAs in the environment will depend on the water pH and their pKa. (scipedia.com)
  • It may also enter the environment through volatilization, spills, and the disposal of chlorpyrifos waste. (cdc.gov)
  • The amount of formaldehyde depends entirely on the interior decoration materials and furniture environmental friendliness, but only in the environment of floor heating, intensified the internal content of volatilization. (dongjiacn.com)
  • In this work, a non-isothermal multi-component two-phase flow model was developed to investigate the thermally induced volatilization and migration of the VOCs in contaminated aquifers. (copernicus.org)
  • For PFOA, we derived a pKa of 0.5 from fitting the experimental measurements with a volatilization model. (scipedia.com)
  • In addition, the aforementioned laminate flooring will have a lot of internal glue bonding, glue composition will have a lot of formaldehyde class, the boiling point of formaldehyde is relatively low, when baked in the floor heating, will accelerate the internal formaldehyde class of substances emitted, and even the volatilization of other substances, so the environmental pollution brought is relatively large. (dongjiacn.com)