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81.
Criteria to protect aquatic life are intended to protect diverse ecosystems, but in practice are usually developed from compilations of single‐species toxicity tests using standard test organisms that were tested in laboratory environments. Species sensitivity distributions (SSDs) developed from these compilations are extrapolated to set aquatic ecosystem criteria. The protectiveness of the approach was critically reviewed with a chronic SSD for cadmium comprising 27 species within 21 genera. Within the data set, one genus had lower cadmium effects concentrations than the SSD fifth percentile‐based criterion, so in theory this genus, the amphipod Hyalella, could be lost or at least allowed some level of harm by this criteria approach. However, population matrix modeling projected only slightly increased extinction risks for a temperate Hyalella population under scenarios similar to the SSD fifth percentile criterion. The criterion value was further compared to cadmium effects concentrations in ecosystem experiments and field studies. Generally, few adverse effects were inferred from ecosystem experiments at concentrations less than the SSD fifth percentile criterion. Exceptions were behavioral impairments in simplified food web studies. No adverse effects were apparent in field studies under conditions that seldom exceeded the criterion. At concentrations greater than the SSD fifth percentile, the magnitudes of adverse effects in the field studies were roughly proportional to the laboratory‐based fraction of species with adverse effects in the SSD. Overall, the modeling and field validation comparisons of the chronic criterion values generally supported the relevance and protectiveness of the SSD fifth percentile approach with cadmium.  相似文献   
82.
Two competing and yet complementary philosophical concepts form the foundation for the legal protection of intellectual property – ‘competing’ in that created works protected by copyright are unavailable for unrestricted use by others as a result of the economic monopoly given to the works’ owners, and ‘complementary’ in that the presumption is that works no longer protected by copyright serve as the basis for the creation of new copyrightable works. These unprotected works comprise the ‘public domain,’ which has never been affirmatively defined. In Golan v. Holder (2012), the US Supreme Court concluded that such a realm is constitutionally unimportant. This research contends, however, that the Court's decision is incorrect, that Golan, federal legislation, and international treaties threaten to bring larger and larger portions of cultural and intellectual content under the control of a property regime that does not understand the contradiction inherent in the notion of absolute property rights in intangible goods. The result is that the public domain is under tremendous pressure from those entities which have the most to gain from expanded authorial rights and from a weakened and less inclusive public domain. Citizens thus will have fewer rights to access and freely use their culture as they choose. The eventual significance of this evolution will be that further creativity and innovation will be stifled, the opposite of the intention of intellectual property law. In this article, we develop an affirmative definition of the public domain, which we believe will correct the imbalance in current intellectual property law.  相似文献   
83.

The Shaping of South African Society 1652–1820, edited by Richard Elphick and Hermann Giliomee. Cape Town: Longman, 1979.  相似文献   
84.
The present meta-analytic review examined the magnitude of the relation between discrete emotion knowledge and three of its most commonly studied correlates in childhood and adolescence: social competence, internalizing problems, and externalizing problems. Emotion knowledge demonstrated small to medium-sized relations with each correlate. Moderators of effect size were also examined and included multiple sample and methodological characteristics. Using random effects models, significant moderators of effect size for relations between emotion knowledge and externalizing problems included sample recruitment, sample age, and the source of externalizing problems ratings. Moderators of effect size were not found for emotion knowledge and social competence, and the effect sizes across samples for emotion knowledge and internalizing problems were homogeneous. Results highlight the relatively consistent yet modest relations between emotion knowledge and its correlates. Implications for applied research and new directions for research on emotion knowledge using innovative methods are discussed.  相似文献   
85.
86.
This article extends research on the consequences of mass imprisonment and the factors shaping population health and health inequalities by considering the associations between imprisonment and population health—measured as life expectancy at birth and the infant mortality rate—and black-white differences in population health using state-level panel data from the United States (= 669), 1980-2004. Results show that imprisonment is significantly associated with poorer population health, though associations between imprisonment and infant mortality and female life expectancy are somewhat more consistently statistically significant than are associations with male life expectancy, and associations are more pronounced and statistically significant for blacks than they are for whites. Results also show, however, that increases in imprisonment are associated with decreases in the mortality rates of young black men. Thus, though imprisonment tends to be associated with higher mortality risk and greater black-white differences in mortality, it may, in the short-run, have some paradoxical mortality benefits for young black men.  相似文献   
87.
Parametric confidence intervals are given for linear combinations of the means of independent Poisson variables and for their continuous versions. The performance of the intervals is assessed using simulation. A real data set is used to compare the proposed intervals with known ones. The proposed intervals are shown to be superior to known ones and comparable to exact intervals.  相似文献   
88.
Despite the prevalence of goal setting in organizations, researchers have not thoroughly examined the implications of goal setting to work outcomes in interdependent work settings. A field survey (n= 442) assessed the relation of goal setting and goal sharing, the extent to which others are aware of an individual's work goal, to performance and conflict across varying levels of task interdependence. The results of moderated regression analyses demonstrate that in highly interdependent tasks, the use of goal setting resulted in lower performance levels. Moreover, goal setting and goal sharing in highly interdependent tasks resulted in individuals' reporting more somatic symptoms. The results are discussed in terms of clarifying the role of goal setting for interdependent tasks.  相似文献   
89.
A mathematical model of receptor-mediated gene expression that includes receptor binding of natural and xenobiotic ligands, protein synthesis and degradation, and metabolism of the xenobiotic ligand was created to identify the determinants of the shape of the dose-response profile. Values of the model's parameters were varied to reflect alternative mechanisms of expression of the protein. These assumptions had dramatic effects on the computed response to a bolus dose of the xenobiotic ligand. If all processes in the model exhibit hyperbolic kinetics, the dose-response curves can appear sigmoidal but actually be linear with a positive slope at low doses. The slope of the curve only approached zero at low dose, indicative of a threshold for response, if binding of the xenobiotic ligand to the receptor exhibited positive cooperativity (ligand binding at one site increases the affinity for ligand at another binding site on the receptor). Positive cooperativity in the rate-limiting step of protein synthesis produced dose-response curves which were "U-shaped" at low doses, also indicative of a threshold. Positive cooperativity in the metabolism of the xenobiotic ligand produced dose-response curves that increased more rapidly than linearly with increasing dose. The model illustrates the fact that response cannot be predicted from qualitative mechanistic arguments alone; any assessment of risk to health from xenobiotic chemicals must be based on a detailed quantitative examination of the kinetic behavior of each chemical species individually.  相似文献   
90.
This review paper examines the effect of matching and mismatching learning style and learning activity and matching and mismatching trainer and trainee learning style on learning achievement. It also explores the possibility of creating a match by promoting learner adaptability or modifying the trainer's training style. The implications of this discussion for training and development are considered.  相似文献   
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