Environmental variability

Simulations of the dynamic motion of proteins aim at sampling relevant portions of the conformational space accessible to the proteins under the influence of environmental variables such as temperature, pressure, and pH. We... 

The performance characteristics of ceramic sensors are defined by one or more of the foUowing material properties bulk, grain boundary, interface, or surface. Sensor response arises from the nonelectrical input because the environmental variable effects charge generation and transport in the sensor material. 

Karably, L. and K. Babcock. Effects of Environmental Variables on Soil Gas Surveys In Superfund 87, The 8th National Conference... 

Armijo, J. S., Intergranular Corrosion of Nonsensitised Austenitic Stainless Steels —Part I Environmental Variables , Corrosion, 21, 235 (1965)... 

The effect of environmental variables upon the logarithm of velocity V5. K relationship has been examined for a few alloys in some conditions of heat treatment. While it cannot be certain that similar results would be obtained with all alloys, the results reported do show interesting features that may have points in common with all alloys. For an Al-Zn-Mg-Cu alloy (7075-T651) the stress-corrosion plateau velocity was a maximum in 5 m KI solution under potentiostatic conditions at -520 mV (v5. S.C.E.), reaching about 2 X 10 to 5 X 10 cm/s, whereas in 3% NaCl under open-circuit... 

Among the physical factors, current velocity has a special significance for benthic biofilms because it can modulate the diffusion of metals through the biofilm and their effects [18, 40]. pH and organic complexation are particularly significant for metal bioavailability [42]. Therefore, metal toxicity will also depend on the influence that environmental variability has on its bioavailability. 

The approach to the evaluation of vibrational spectra described above is based on classical simulations for which quantum corrections are possible. The incorporation of quantum effects directly in simulations of large molecular systems is one of the most challenging areas in theoretical chemistry today. The development of quantum simulation methods is particularly important in the area of molecular spectroscopy for which quantum effects can be important and where the goal is to use simulations to help understand the structural and dynamical origins of changes in spectral lineshapes with environmental variables such as the temperature. The direct evaluation of quantum time- correlation functions for anharmonic systems is extremely difficult. Our initial approach to the evaluation of finite temperature anharmonic effects on vibrational lineshapes is derived from the fact that the moments of the vibrational lineshape spectrum can be expressed as functions of expectation values of positional and momentum operators. These expectation values can be evaluated using extremely efficient quantum Monte-Carlo techniques. The main points are summarized below. 

The ability to change and control the composition of the nutrient solution and the relatively small size of the microcosms used enables manipulation of environmental variables and time-course studies of rhizodeposition to be made relatively easily. The influence of nutrient availability, mechanical impedance, pH, water availability, temperature, anoxia, light intensity, CO2 concentration, and microorganisms have all been examined within a range of plant species (9). A few examples to illustrate the continued interest in examining the effect of such variables on rhizodeposition in nutrient culture are given in Table 1. 

To what extent do environmental variables such as diet and substances have an influence in pharmacotherapy Can we minimize the adverse impact of drug-substance and drug-herb interactions ... 

The individual risk for drag inefficacy or drug toxicity is a product of the interaction of genes and the environment. Environmental variables include nutritional factors, concommittantly administered drugs, disease and many other factors in-... 

When using fluorophores of known lifetime, it is important to validate the lifetime used. Fluorescence lifetimes can be sensitive to concentration, temperature, pH, and other environmental variables. Fluorophores from different suppliers can have variable purity. As a result, one should not assume that a value reported in the literature will be exactly transferable to other labs and conditions. Users of the method should be particularly careful to use low concentrations of fluorophore (<10 /iM) to avoid a variety of processes which can perturb lifetimes in solution. There are a limited number of well characterized fluorophores. If one is not available for a particular wavelength this will require a change of filters leaving the method with nothing to recommend it over reflection and scatter. 

Landrum, P.F. (1988) Toxicokinetics of organic xenobiotics in the amphipod Pontoporeia hoyi role of physiological and environmental variables. Aqua. Toxicol. 12, 245-271. 

Fig. 4 Redundance analysis (RDA) on phytoplankton communities collected during the surveys of 2005-2006 and their relationship with the environmental variables, such as the Total Phosphorus (PTOT), Water Flow (WATFL), Total Suspended Solids (TSS), ammonia concentration (NH4), nitrate concentration (N03), and conductivity (COND). Acronyms were also used for phytoplankton taxa representation...

Wren, C.D. and H.R. Mac Crimmon. 1983. Mercury levels in the sunfish, Icpomis gibbosus, relative to pH and other environmental variables of precambrian shield lakes. Canad Jour. Fish. Aquat. Sci. 40 1737-1744. 

Nuruzzaman H, Lambers H, Bolland MDA, Veneklaas EJ (2006) Distribution of carboxylates and acid phosphatase and depletion of different phosphorus fractions in the rhizosphere of a cereal and three grain legumes. Plant Soil 281 109-120 Olde Venterink H, Wassen MJ, Belgers JDM, Verhoeven JTA (2001) Control of environmental variables on species density in fens and meadows importance of direct effects and effects through community biomass. J Ecol 89 1033-1040. doi http //www.blackwell-synergy.com/ doi/abs/10.111 l/j.1365-2745.2001.00616.x... 

Abiotic organic reactions, such as hydrolysis, elimination, substitution, redox, and polymerization reactions, can be influenced by surfaces of clay and primary minerals, and of metal oxides. This influence is due to adsorption of the reactants to surface Lewis and Br nsted sites. Temperature and moisture content are the most important environmental variables. Under ambient environmental temperatures, some reactions are extremely slow. However, even extremely slow transformation reactions may be important from environmental and geochemical viewpoints. 

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