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Reproduction definition

Derived plant and animal products make better use or upgrade the nutritional quaHty of already existing materials or products. Synthetic and manufactured products arose from knowledge of the functional properties of food ingredients and of human and animal nutrition that involved more precise definition of nutrient requirements for growth, reproduction, lactation, and body maintenance in both humans and domestic Hvestock. Pood products have been developed to meet human needs under abnormal environments, eg, military rations for arctic, tropical, or desert environments, and special products for astronauts ia space flights. [Pg.463]

A major difficulty which has been encountered with these definitions (identified as a particular problem by EDSTAC) is the definition of the term adverse . For a chemical to be judged an ED, it is important to show that the response seen has an adverse effect on the health or reproductive capacity of affected organisms or populations and is not just a change which falls within the normal range of physiological variation. [Pg.5]

Instead of reproduction or replication , the more general term production was used. The third definition includes the first definition. However, because it contains neither Darwinian nor genetic specification, this definition takes both coded and uncoded life into account. Since the term population is not included, the definition can be applied to single objects such as robots. [Pg.14]

Fig. 1.5 Schematic representation of the evolution of life from its precursors, on the basis of the definition of life given by the authors. If bioenergetic mechanisms have developed via autonomous systems, the thermodynamic basis for the beginning of the archiving of information, and thus for a one-polymer world such as the RNA world , has been set up. Several models for this transition have been discussed. This phase of development is possibly the starting point for the process of Darwinian evolution (with reproduction, variation and heredity), but still without any separation between genotype and phenotype. According to the authors definition, life begins in exactly that moment when the genetic code comes into play, i.e., in the transition from a one-polymer world to a two-polymer world . The last phase, open-ended evolution, then follows. After Ruiz-Mirazo et al. (2004)... Fig. 1.5 Schematic representation of the evolution of life from its precursors, on the basis of the definition of life given by the authors. If bioenergetic mechanisms have developed via autonomous systems, the thermodynamic basis for the beginning of the archiving of information, and thus for a one-polymer world such as the RNA world , has been set up. Several models for this transition have been discussed. This phase of development is possibly the starting point for the process of Darwinian evolution (with reproduction, variation and heredity), but still without any separation between genotype and phenotype. According to the authors definition, life begins in exactly that moment when the genetic code comes into play, i.e., in the transition from a one-polymer world to a two-polymer world . The last phase, open-ended evolution, then follows. After Ruiz-Mirazo et al. (2004)...
No definitive, quantitative data were available regarding the potential reproductive and developmental toxicity of arsine in humans. [Pg.93]

Whichever interpretation is correct, Kalecki s silence on the labour theory of value leaves open the theoretical possibility that its relevance can be fruitfully explored. To relate Kalecki s model of reproduction to Marx s theory, a reconfiguration is required of the definition of profits. The problem, as we have seen, is that Kalecki s model requires a gross definition of profits that is different from Marx s category of surplus value. The Kalecki principle has not been precisely demonstrated in the context of Marx s reproduction schema, in which surplus value is the key category of analysis. [Pg.26]

This contradiction bears a close resemblance to Luxemburg s posing of the question of how new capital goods can be produced in the absence of sufficient demand to satisfy the new capacity. Sufficient demand, to meet the requirements of a balanced growth in capacity, is unlikely to be forthcoming from within the Domar model, from within the reproduction schema. Joan Robinson s interpretation of Luxemburg has some resonance with the Domar definition of the problem ... [Pg.74]

Reproductive Effects. It has not been definitively determined whether chloroform exposure induces reproductive effects in humans. No studies were located regarding reproductive effects in humans after inhalation or dermal exposure to chloroform. Only one study was located regarding reproductive effects in humans after oral exposure to chloroform. Bove et al. (1995) studied the effects of drinking-water consumption on birth outcomes and found that exposure to TTHM at levels >0.1 ppm resulted in reduced birth weight and size as well as an increased risk of oral cleft, central nervous system, and neural tube defects. These results should be viewed with caution since the authors did not specifically monitor chloroform levels. The effects seen may be due to exposure to other THMs or non-THM contaminants in the drinking water. [Pg.156]

The adverse reproductive effects are considered as being threshold effects, i.e., effects for which there are expected to be a threshold of substance concentration below which the effects will not be manifested. For the hazard and risk assessment, it is important to identify those dose levels at which adverse reproductive effects are observed, and the dose level at which adverse reproductive effects are not observed, i.e., to derive a NOAEL for reproductive toxicity. Crucial in the derivation of the NOAEL and/or LOAEL, is the definition of adverse effects (Section 4.2.2). In the derivation of the NOAEL and/or LOAEL, a number of factors need to be considered these issues are addressed in detail in Sections 4.2.3 and 4.2.4. An alternative approach to the derivation of the... [Pg.185]

The reproductive/developmental toxicity screening test can provide initial information on possible effects on reproduction and/or development and may make it possible to identify a substance as being toxic to reproduction, i.e., the test gives a clear positive result. However, this test offers only limited means of detecting postnatal manifestations of prenatal exposure or effects that may be induced during postnatal exposure. In addition, because of the study design (e.g., relatively small numbers of animals per dose level, relatively short smdy duration), the test will not provide evidence for definite claims of no effects. [Pg.187]

In vitro studies will not, in the absence of more definitive data, provide a basis for a firm decision about the reproductive toxicity of a substance. Positive results from such smdies indicate that there may be some concern in relation to the potential for reproductive toxicity, but they can be overridden by clearly negative data from well-conducted test guideline smdies for reproductive toxicity. Negative data from in vitro smdies, if well conducted, may contribute to the weight of evidence. [Pg.188]


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See also in sourсe #XX -- [ Pg.124 ]




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