Lexikon
adenosine-triphosphate, the main energy storage and transfer molecule in the cell.
attenuation in general means the reduction of a material flux, decreasing velocity of a process, the reduction of the strength of a signal or the act of thinning or weakening of any affects. The term attenuation is used in physics, in biology, microbiology, virology and in environmental sciences.
In physics/electronics it is used for the reduction of signal strength during transmission. Attenuation is the opposite of amplification, and is normal when a signal is sent from one point to another. Networks require repeaters at regular intervals to compensate attenuation. This kind of attenuation is measured in decibels.
Physical attenuation can be demonstrated by the following examples:
- light attenuation in water with depths
- transmission loss in fiber optics
- light scattering
- UV or IR absorption and selective absorption by different molecules and materials
- attenuation of radio signals
- seismic vawe attenuation, etc.
Attenuation in the biology and microbiology means mainly the thinning or weakening, such as the slowing down of the fermentation process of yeast cells paralel to the consumption of the substrates or the alteration of virulence of a pathogenic microorganism by passage through another host species, decreasing the virulence of the organism for the native host and increasing it for the new host. In gene trascription and expression attenuation means a self-regulating mechanism, resulting in the premature termination of the transcription.
In environmental management and engineering, attenuation is a process whereby the concentration of contaminants are managed, removed, or reduced by a risk reduction technology. Attenuation may be accomplished naturally under certain conditions due to dispersion, dilution, photodegradation, hídrolysis, biodegradation or the combination of all these natural processe.
Atterberg limits are a basic measure of the nature of a fine-grained soil. Depending on the water content of the soil, it may appear in four states: solid, semi-solid, plastic and liquid. In each state the consistency and behavior of a soil is different and thus so are its engineering properties. Thus, the boundary between each state can be defined based on a change in the soil's behavior. The Atterberg limits can be used to distinguish between silt and clay, and it can distinguish between different types of silts and clays.
The shrinkage limit (SL) is the water content where further loss of moisture will not result in any more volume reduction. The test to determine the shrinkage limit is ASTM International D4943. The shrinkage limit is much less commonly used than the liquid limit and the plastic limit.
The plastic limit (PL) is the water content where soil starts to exhibit plastic behavior. A thread of soil is at its plastic limit when it is rolled to a diameter of 3 mm or begins to crumble. To improve consistency, a 3 mm diameter rod is often used to gauge the thickness of the thread when conducting the test. (AKA Soil Snake Test)
The liquid limit (LL) is the water content where a soil changes from plastic to liquid behavior. The original liquid limit test of Atterberg's involved mixing a pat of clay in a little round-bottomed porcelain bowl of 10-12cm diameter. A groove was cut through the pat of clay with a spatula, and the bowl was then struck many times against the palm of one hand.
Derived indexes:
The plasticity index (PI) is a measure of the plasticity of a soil. The plasticity index is the size of the range of water contents where the soil exhibits plastic properties. The PI is the difference between the liquid limit and the plastic limit (PI = LL-PL). Soils with a high PI tend to be clay, those with a lower PI tend to be silt, and those with a PI of 0 tend to have little or no silt or clay.
The liquidity index (LI) is used for scaling the natural water content of a soil sample to the limits. It can be calculated as a ratio of difference between natural water content, plastic limit, and plasticity index: LI=(W-PL)/(LL-PL) where W is the natural water content.
The activity (A) of a soil is the PI divided by the percent of clay-sized particles(less than 0.075mm size) present. Different types of clays have different specific surface areas which controls how much wetting is required to move a soil from one phase to another such as across the liquid limit or the plastic limit. From the activity one can predict the dominant clay type present in a soil sample. High activity signifies large volume change when wetted and large shrinkage when dried. Soil with high activity are very reactive chemically.
Normally, activity of clay is between 0.75 and 1.25 and in this range, clay is called normal. It is assumed that the plasticity index is approximately equal to the clay fraction (A = 1). When A is less than 0.75, it is considered inactive. When it is greater than 1.25, it is considered active.
Source: Wikipedia, http://en.wikipedia.org/wiki/Atterberg_limits
the REACH Regulation sets up a system under which the use of substances with properties of very high concern and their placing on the market can be made subject to an authorisation requirement. Such substances are included in Annex XIV of the Regulation, and may not be placed on the market or used without an authorisation.This authorisation requirement ensures that risks from the use of such substances are either adequately controlled or outweighed by socio-economic benefits. An analysis of alternative substances or technologies will be a fundamental component of the authorisation process. Source: REACH Glossary
autoimmun response is a condition in which the immune system attacks tissues in its own body. This happens if the immune system gets signals telling it that the body tissue is an outside invader. This false signal causes several diseases, such as rheomatoid athritis, lung emphysema, allergies, etc.
The following list gives some of the autoimmune diseases:
Acute disseminated encephalomyelitis (ADEM)
Autoimmune aplastic anemia
Autoimmune lymphoproliferative syndrome
Autoimmune peripheral neuropathy
Autoimmune polyendocrine syndrome
Autoimmune progesterone dermatitis
Autoimmune thrombocytopenic purpura
Balo disease/Balo concentric sclerosis
Chronic inflammatory demyelinating polyneuropathy
Chronic recurrent multifocal osteomyelitis
Chronic obstructive pulmonary disease
Complement component 2 deficiency
Crohn's disease (one of two types of idiopathic inflammatory bowel disease "IBD")
Cutaneous leukocytoclastic angiitis
Diffuse cutaneous systemic sclerosis
Enthesitis-related arthritis[28]
Epidermolysis bullosa acquisita
Erythroblastosis fetalis
Essential mixed cryoglobulinemia
Fibrodysplasia ossificans progressiva
Fibrosing alveolitis (or Idiopathic pulmonary fibrosis)
Guillain-Barré syndrome (GBS)
Herpes gestationis aka Gestational Pemphigoid
Idiopathic inflammatory demyelinating diseases
Idiopathic thrombocytopenic purpura (See Autoimmune thrombocytopenic purpura)
Chronic inflammatory demyelinating polyneuropathy
Juvenile idiopathic arthritis aka Juvenile rheumatoid arthritis
Lambert-Eaton myasthenic syndrome
Linear IgA disease (LAD)
Lou Gehrig's disease (Also Amyotrophic lateral sclerosis)
Lupoid hepatitis aka Autoimmune hepatitis
Miller-Fisher syndrome see Guillain-Barre Syndrome
Mixed connective tissue disease
Mucha-Habermann disease aka Pityriasis lichenoides et varioliformis acuta
Neuromyelitis optica (also Devic's disease)
Occular cicatricial pemphigoid
PANDAS (pediatric autoimmune neuropsychiatric disorders associated with streptococcus)
Paraneoplastic cerebellar degeneration
Paroxysmal nocturnal hemoglobinuria (PNH)
Primary sclerosing cholangitis
Progressive inflammatory neuropathy
Schmidt syndrome another form of APS
Still's disease see Juvenile Rheumatoid Arthritis
Subacute bacterial endocarditis (SBE)
Systemic lupus erythematosis see Lupus erythematosis
Temporal arteritis (also known as "giant cell arteritis")
Ulcerative colitis (one of two types of idiopathic inflammatory bowel disease "IBD")
Undifferentiated connective tissue disease different from Mixed connective tissue disease
Undifferentiated spondyloarthropathy
Source: http://en.wikipedia.org/wiki/Autoimmune_disease
an axiom is a mathematical rule. This basic assumption about a system allows theorems to be developed. For example, the system could be the points and lines in the plane. Then an axiom would be that given any two distinct points in the plane, there is a unique line through them.
an axon (also known as a nerve fiber) is a long, slender projection of a nerve cell (neuron), that typically conducts electrical impulses away from the neuron's cell body.
In certain sensory neurons (pseudounipolar neurons), the impulse travels along an axon from the periphery to the cell body, and from the cell body to the spinal cord along another branch of the same axon. Axon dysfunction causes many inherited and acquired neurological disorders which can affect both the peripheral and central neurons.
an inherited, degenerative disorder of the peripheral and central nervous system or a disorder caused by neurotoxins.
an average or expected concentration of a substance l in a specific environment, or typical concentrations of substances that occur naturally in an environment.
an average or expected imission in the environment of an air polluting source.
bacteria usually control gene expression by regulating the level of mRNA transcription. In bacteria, genes with related function are generally located adjacent to each other and they are regulated co-ordinately . Coordinate regulation of clustered genes is accomplished by regulating the production of a polycistronic mRNA (a large mRNA containing the information for several genes). Thus, bacteria are able to "sense" their environment and express the appropriate set of genes needed for that environment by regulating transcription of those genes.
Bactericides are substances that kill bacteria. Bactericides are either disinfectants, antiseptics or antibiotics. Bactericides are widely used in human and animal therapy, in agriculture plant pesticides and in different industries for killing harmful bacteria.
bacterostatic agent or shotly bacteriostat is a biological or chemical agent that stops bacteria from reproducing, while not necessarily harming them otherwise.
Depending on their application, bacteriostatic antibiotics, disinfectants, antiseptics and preservatives can be distinguished. Upon removal of the bacteriostat, the bacteria usually start to grow again. This is in contrast to bactericides, which kill bacteria.
BioAccumulation Factor is the ratio between concentration in an organism or in a part or organ of an organism, and exposure level, = environmental concentration. It is also called Bioconcentration Factor, BCF.
unit of pressure. Normal atmospheric pressure 1 atmosphere = 1.013 bar (= 1013 mbar).
a barrel is a hollow cylindrical container, traditionally made of vertical wooden staves and bound by wooden or metal hoops.
Barrel is also one of several units of volume, with dry barrels, fluid barrels (UK beer barrel, U.S. beer barrel), oil barrel, etc. The conversion to other units of volume:
| barrels, US beer | gallons | 31 |
| barrels, US beer | liters | 117.347 77 |
| barrels, US petroleum | gallons (British) | 34.97 |
| barrels, US petroleum | gallons (US) | 42 |
| barrels, US petroleum | liters | 158.987 29 |
| barrels, US proof spirits | gallons | 40 |
| barrels, US proof spirits | liters | 151.416 47 |
adopted in 1989 and entered into force on 5 May 1992. The Basel Convention on the Control of Transboundary Movements of Hazardous Wastes and their Disposal aims to minimise the generation of hazardous wastes and control their movement.
Best Available Techniques Not Entailing Excessive Cost.
An electrical battery consists of one or more electrochemical cells, which are able to convert the chemical energy stored in the battery into electrical energy. The cell was developed by Alessandro Volta, in 1800. Today, the battery is a common power source for households, industries and toys.
Batteries may be used once and discarded, or recharged for years as in standby power applications. Miniature cells are used to power devices such as wristwatches and portable electronic devices; larger batteries provide standby power for telephone exchanges or computer data centers, for cars and other vehicles, incuding electric cars.
The 2006/66/EC European Directive (see the Summary of EU waste Legislation on Batteries and Accumulators) aims at minimising the negative impacts of batteries and accumulators on the environment. The Directive introduces measures to prohibit the marketing of some batteries containing hazardous substances. The Directive contains measures for establishing schemes aiming at high level of collection and recycling of batteries with quantified collection and recycling targets.
BEVs store electricity in batteries and draw power from the batteries to run an electric motor that drives the vehicle. So long as the ultimat electricity source is clean, the BEV system can reduce emissions significantly compared with an internal combustion engine vehicle (ICEV) run on a liquid fuel. Indeed, BEVs using WWS power would be completely zero-emission vehicles. Moreover, BEVs get about 5 times more work (in miles of travel) per unit of input energy than do ICEVs (mi/kWh-outlet versus mi/kWh-gasoline). BEVs have existed for decades in small levels of production, and today most major automobile companies are developing BEVs. The latest generation of vehicles uses lithium-ion batteries, which do not use the toxic chemicals associated with lead-acid or the nickel-cadmium batteries (1).
Vehicles using both electric motors and internal combustion engines are examples of hybrid electric vehicles, and are not considered pure (or all) EVs because they operate in a charge-sustaining mode.
- Regular hybrid electric vehicles cannot be externally charged.
- Hybrid vehicles with batteries that can be charged externally to displace some or all of their internal combustion engine power and gasoline fuel are called plug-in hybrid electric vehicles (PHEV), and are BEVs during their charge-depleting mode.
All-electric and plug-in hybrids are off-vehicle charge capable. (“OVCC” or pluginable), which means their batteries can be charged from an off-vehicle electric energy source that cannot be connected or coupled to the vehicle while the vehicle is being driven (2)
Sources:
(1) Mark Z. Jacobson and Mark A. Delucchi: Evaluating the Feasibility of a Large-Scale Wind, Water, and Sun Energy Infrastructure
(2) http://en.wikipedia.org/wiki/Battery_electric_vehicle
the BMD concept involves fitting a mathematical model to dose-response data. The BMD is defined as the dose causing a predetermined change in response.
Source: REACH
the BMD concept involves fitting a mathematical model to dose-response data. The BMD is defined as the dose causing a predetermined change in response.
The BMD10 Benchmark-dose associated with a 10% response (for tumours upon lifetime exposure after correction for spontaneous incidence, for other effects in a specified study.
The BMDL10 is the lower 95% confidence interval of a Benchmark-dose representing a 10% response (e.g., tumour response upon lifetime exposure), i.e. the lower 95% confidence interval of a BMD10. (Source: REACH Glossary)
benthos is the community of organisms which live in the bed sediment of freshwater or the sea, in the so called benthic zone.
The size of living organisms may vary largely, some of them are microorganisms, not or hardfly visible by naked eyes, these constitute microbenthos. The bigger ones belong to the mezo or macrobenthos.
Benthic community of freshwater and the sea are significantly different.
Light does not penetrate very deep waters, that is why the energy source for deep benthic ecosystems is often organic matter from higher up in the water column which drifts down to the depths. This dead and decaying matter sustains the benthic food chain; most organisms in the benthic zone are scavengers or detritivores.
See also zoobenthos.
a colorless liquid with a sweet odor. It belongs to hydrocarbons, the simplest representative of aromatics with chemical formula of C6H6. Its boiling temperature is 80,5 °C, melting temperature 6 °C, specific gravity 0.880 g/cm3 at 20 °C. It evaporates into the air very quickly and dissolves slightly in water. It is highly flammable and is formed from both natural processes and human activities. Natural sources of benzene include emissions from volcanoes and forest fires. benzene is also a natural part of crude oil, gasoline, and cigarette smoke.benzene is widely used to make other chemicals which are applied to make plastics, resins, and nylon and other synthetic fibers. benzene is also used to make some types of rubbers, lubricants, dyes, detergents, drugs, and pesticides. It breaks down slowly in water and soil, and can pass through the soil into underground water. benzene does not build up in plants or animals. Breathing very high levels of benzene can result in death, while high levels can cause drowsiness, dizziness, rapid heart rate, headaches, tremors, confusion, and unconsciousness. Eating or drinking foods containing high levels of benzene can cause vomiting, irritation of the stomach, dizziness, sleepiness, convulsions, rapid heart rate, and death. The major effect of benzene from long-term exposure is on the blood. benzene causes harmful effects on the bone marrow and can cause a decrease in red blood cells leading to anemia. It can also cause excessive bleeding and can affect the immune system, increasing the chance for infection. Long-term exposure to high levels of benzene in the air can cause leukemia, particularly acute myelogenous leukemia, often referred to as AML. This is a cancer of the bloodforming organs. The Department of Health and Human Services (DHHS) in the USA has determined that benzene is a known carcinogen. The International Agency for Research on Cancer (IARC) and the EPA have determined that benzene is carcinogenic to humans. (Source: Agency for Toxic Substances and Deseas Registry, ATSDR, www.atsdr.cdc.gov)
benzene, or benzol, is an aromatic ring with the molecular formula C6H6. benzene is a colorless and flammable liquid with a strong smell and a relatively high melting point. Because it is a known carcinogen, its use as in gasoline is now limited, but it is an important industrialsolvent and precursor in the production of drugs and plastics. benzene is a natural constituent of mineral oil.
Alkylbenzenes are organic compounds that has an alkyl group bound to a benzene ring. Two well known alkylbenzenes are methylbenzene and toluene, both are colorless flammable liquids obtained from petroleum or coal tar, used as a solvent for gums and lacquers and in high-octane fuels. See also BTEX.
Best Environmental Practices (BEPs), the application of the most appropriate combination of environmental control measures or strategies in order to reduce the impact of specific substances or applications.
the Best Practicable Environmental Option BPEO Twelfth Report, FEB 1988, Cm 310, is a set of procedures adopted by Great Britain with the goal of managing waste and other environmental concerns. According to the Royal Commission on Environmental Pollution, BPEO "emphasises the protection and conservation of the environment across land, air and water. The BPEO procedure establishes for a given set of objectives, the option that provides the most benefits or the least damage to the environment, as a whole, at acceptable cost, in the long term as well as in the short term."
Source: Wikipedia, http://en.wikipedia.org/wiki/Best_practicable_environmental_option
one thousand million (in the U.S.). 1,000,000,000=109.
a microbial, plant or animal species whose presence, abundance, and health reveal the general condition of its habitat. The specific chemical, biochemical or genetical characteristic or molecule of these species can also function and bio-indicator. These bio-indicators can be used as measured endpoints in ecological surveys or ecotoxicological test methods.