Biological characteristics

Biological characteristics include microscopic and chromatographic examinations, plate counts, total heterotrophs, petroleum degrading, total hydrogen degrading, bacteria microscopic examination, and TOC. 

Microscopic Examination Microscopic examination involves a slurry derived from fresh soil that is examined under high magnification for bacterial type, cell health, protozoans, and approximate number of bacteria. 

Total Heterotrophs This tests for all bacteria capable of using organic carbon as an energy source. The number obtained from this test is compared with background samples from similar soil types of similar depths, and compared with the number of hydrocarbon-degrading bacteria within the same sample. 

Petroleum Degraders This test cultures bacteria that are able to grow using petroleum as the sole carbon source. A popular variation of this test is called the 

Total Organic Carbon Formations with a significant TOC content greater than the petroleum hydrocarbon content, as with peat-rich soil, can compete with the hydrocarbon-degrading microbes for oxygen and nutrients. A representative sample should thus be analyzed for TOC if organic matter is observed in soil samples or borings. 

Comparison of Selected Soil Physical and Chemical Properties (0-20 cm) among Wetland Types 

Note BD = bulk density OM = organic matter N = nitrogen P = phosphorus Ex-Ca = exchangeable calcium Ex-Mg = exchangeable magnesium Ox-Fe = oxalate extractable iron Ox-Al = oxalate extractable aluminum (summarized by Faulkner and Richardson, 1989). 

FIGURE 3.8 Schematic of changes in microbial communities after a flooding event. 

which are active in upland environments, cease to exist in wetland soils. This is primarily due to the absence of oxygen and alteration in soil pH (acid to neutral) under anaerobic conditions. Overall, microbial biomass decreases under saturated soil conditions. The metabolic activities of anaerobic bacteria depend on alternate electron acceptors, such as oxidized forms of nitrogen, iron, manganese, and sulfur. Under wetland soil conditions, rates of many microbially mediated reactions decline, and some reactions may be eliminated and replaced by new ones. New microbial reactions are involved in the reduction of oxidized compounds during respiratory processes, resulting in the production of reduced compounds. 

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This chapter discusses the kinetics, modeling and simulation of biochemical reactions, types and scale-up of bioreactors. The chapter provides definitions and summary of biological characteristics. 

George DG, Maberly SC, Hewitt DP (2004) The influence of the North Atlantic Oscillation on the physical, chemical and biological characteristics of four lakes in the English Lake District. Freshw Biol 49 760-774... 

Purification of biopharmaceuticals often involves the removal of materials with physical characteristics very similar to the desired product, such as failure sequences from DNA synthesis or misfolded proteins from bacterial fermentations. The contaminants, however, may have biological characteristics very different from the desired product, including different antigenicities, bioactivities, and specificities. There are even systems in which the... 

This chapter describes examples of the chemical/biologi-cal threat agents that might be used in a terrorist attack on the U.S. air transportation system, as well as some key physical, chemical, and biological characteristics of these agents that would affect the number of people exposed to such an attack. Some plausible scenarios for the release of these agents into the air transportation environment are also discussed. 

Many types of threat agents might be used in an attack on the air transportation system. Each has its own set of physical, chemical, and biological characteristics, which would determine how lethal and widely dispersed the effects would be. Four different categories of threat agents can be distinguished 1... 

Ionization is the process of separation or dissociation of a molecule into particles of opposite electrical charge (ions). The presence and extent of ionization has a large effect on the chemical behavior of a substance. An acid or base that is extensively ionized may have markedly different solubility, sorption, toxicity, and biological characteristics than the corresponding neutral compound. Inorganic and organic acids, bases, and salts may be ionized under environmental conditions. A weak acid HA will ionize to some extent in water according to the reaction ... 

Lundstedt-Enkel K, Johansson AK, Tysklind M, Asplund L, Nylund K, Olsson M, Orberg J (2005) Multivariate data analyses of chlorinated and brominated contaminants and biological characteristics in adult guillemot (Uria aalge) from the Baltic Sea. Environ Sci Technol 39(22) 8630-8637. doi 10.1021/es051118o... 

Nativists contend that genetically determined traits are characteristic of specific racial groups and that cultures themselves can be reduced to biological characteristics. Extremists have opposed immigration with arguments that the inferiority of some races is a biological fact based on evolutionary... 

Environmental contamination, either from diffuse or point sources, may compromise the ability of ecosystems to provide society with those goods and services that we require. Contamination is also linked to other widely recognised anthropogenic threats to sustainable functioning of our planet, such as the loss of biodiversity. As many soil properties and processes are conferred by soil biota, it is currently widely agreed that biological characteristics should be taken into account when evaluating the quality, or health, of soil [13, 16]. 

The expression of the active transport systems is time-dependent and may vary with nutritional conditions [53, 54]. The culturing conditions, e.g., the passaging process, can dramatically alter the biological characteristics and transport properties of Caco-2 cell monolayers [55-58]. 

Clarke, S. J., Hollmann, C. A., Aldaye, F. A. and Nadeau, J. L. (2008). Effect of ligand density on the spectral, physical, and biological characteristics of CdSe/ZnS quantum dots. Bioconjug. Chem. 19, 562-8. 

The specific values of the physical and biological characteristics such as breathing patterns for occupational exposure and active and resting patterns for environmental exposure are given in the footnotes to the Tables. A few remarks should be made concerning the parameters used which affect the dose calculation significantly. 

Gregorich EG, Beare MH, McKim UF, Skjemstad JO (2006) Chemical and biological characteristics of physically uncomplexed organic matter. Soil Sci Soc Am J 70 975-985... 

Widmer F, Fliepbach A, Laczko E, Shulze-Aurich J, Zeyer J (2001) Assessing soil biological characteristics a comparison of bulk soil community DNA-, PLFA, and Biolog -analyses. Soil Biol Biochem 33 1029-1036... 

Manipulation. Autologous, allogenic, or xenogenic cells which have been expanded propagated manipulated or had their biological characteristics altered ex vivo (e.g., TIL or LAK cells islet cells housed in a membrane). 

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