Laboratory model organisms

Application of radiolabeled mirex to plants grown in a terrestrial/aquatic laboratory model ecosystem indicated that when the plant leaves were eaten by caterpillars, the aquatic system became contaminated. Mirex was detected in all segments of two aquatic food chains (alga > snail and plankton > daphnia > mosquito > fish) within 33 days. Undegraded mirex contributed to over 98.6, 99.4, 99.6, and 97.9% of the radiolabel in fish, snails, mosquitoes, and algae, respectively. No metabolites of mirex were found in any of the organisms (Francis and Metcalf 1984 Metcalf et al. 1973). 

As seen in Chapter 9.C.2, a very wide variety of organics are found in particles in ambient air and in laboratory model systems. The most common means of identification and measurement of these species is mass spectrometiy (MS), combined with either thermal separation or solvent extraction and gas chromatographic separation combined with mass spectrometry and/or flame ionization detection. For larger, low-volatility organics, high-performance liquid chromatography (HPLC) is used, combined with various detectors such as absorption, fluorescence, and mass spectrometry. For applications of HPLC to the separation, detection, and measurement of polycyclic aromatic hydrocarbons, see Wingen et al. (1998) and references therein. 

Concentration and Recovery of Solutes. The RO method was evaluated by using small-scale concentrations and selected model organic solutes. Similar concentrations were performed by other researchers by using alternate sampling methods as part of a comparison study. The concentration provided a 50-fold volume reduction (500 L down to 10 L). Field applications of the RO method usually involve sample volumes of 2000-8000 L. No steps were taken to condition membranes and equipment prior to the laboratory tests. This laboratory performance evaluation was conducted, in many respects, as a worst case exercise. 

Cultivation of the plasmodium of myxomycetes in a practical scale has been known only for very limited species. Physarum polycephalum may be the most familiar species of myxomycetes because of the ease with which its plasmodium may be grown in the laboratory. It has been therefore used extensively in physiological, biochemical, and genetic studies as well as in schools for model organisms. Mass culture of the plasmodia of Physarum polycephalum... 

BioProtocols. B1O.COM. URL http //www.bio.com/protocol-stools/index.jhtml. Includes protocols for cell biology, chromatin, ethanol, laboratory methods, model organisms, molecular biology, and plant biology. 

The approaches to the creation of universal system of biosensors for ecological monitoring using bioluminescent organisms and their enzymes and to devise a laboratory model of a biosensors system are discussed."... 

Owing to its practical importance and its toxicity to warm-blooded organisms, its metabolism has been investigated extensively on various test objects, including a laboratory model ecosystem (Metcalf et al., 1968 Ashworth and Sheets, 1972 Dorough, 1968 Knaak et al., 1970 Yu et al., 1974). The most important metabolites are 3-hydroxycarbofuran (17) and its glucoside, and 3-ketocarbofuran... 

The review of phosphorus models by Lewis and McCechan (2002) showed that one of the major differences in phosphorus cycling models is the number of inorganic and organic phosphorus pools and the ability to measure them in the laboratory. Models such as CENTURY have included phosphorus pools that are conceptually important for the model structure, but are difficult to measure. For example, the CENTURY model includes separate pools for parent phosphorus, strongly sorbed phosphate and occluded phosphorus, while... 

There are only a few studies of the biological utilization of Cd and they have been restricted to marine phytoplankton. It may be that Cd is only a useful element in marine phytoplankton or it may be that Cd has more widespread biological uses, which have been masked so far by the similar, perhaps redundant, and more obvious role of Zn in the model organisms studied in the laboratory. In any case the discovery of the biological role of Cd in phytoplankton owes much to the obvious clue provided by its vertical concentration profiles in the oceans [19-22,44] (Fig. 4). 

Shaffer, H. B., 1993, Phylogenetics of model organisms The laboratory axolotl, Ambystoma mexicanum, Syst. Biol. 42 508-522. 

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