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991.
992.
Resource development in the western United States of America offers the prospect of rapid population and economic growth which may dramatically alter the traditional social bases of these rural communities. Reports from other western boomtowns suggests that such rapid growth can lead to substantial community disruption with a disproportionate increase in social problems and an eventual lowered productivity in the synthetic fuels industry. Changes related to population growth need not produce such disruptive results. Cooperation among industry, government, and community and well planned and coordinated human services and programs designed to relieve the stresses of change, to provide a sense of community, and to integrate newcomers into the community can reduce or prevent many of the negative impacts as well as reduce overall costs by building on existing resources. 相似文献
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Summary Play behavior of young ponies accounted for two-thirds of total running exercise and over 95% of all high-speed turns in ten animals from birth to age six weeks. The classical supposition, never previously demonstrated, that most exercise of young mammals occurs in play, is confirmed in these subjects. 相似文献
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Behavioral Ecology and Sociobiology - 相似文献
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Environmental Conflicts and the SLAPP 总被引:1,自引:0,他引:1
Terrance M. Hurley Visiting Scientist Jason F. Shogren Thomas Stroock Distinguished Professor of Natural Resource Conservation Management 《Journal of Environmental Economics and Management》1997,33(3):253-273
A citizen has the right to challenge a firm's actions regarding development plans or violations of environmental laws. Firms have responded with the SLAPP—Strategic Lawsuit Against Public Participation. Fearing the loss of the Constitutional Right to Petition, several U.S. states have or are considering explicitly restricting the SLAPP. For a class of environmental conflict models with one-sided asymmetric information, our results suggest that restricting the SLAPP does not increase the efficiency of the dispute. 相似文献
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The fate of pesticides in soil is incompletely described by the analytical determination of applied pesticides because a differentiation between the processes degradation and sorption which determine pesticide concentration in soils is not possible. By analyzing corresponding metabolites, degradation can be confirmed. Detailed mass balances considering the mineralization and formation of non-extractable residues are set up in closed model systems applying radiotracer techniques. This complex laboratory data can only be transferred to field conditions by mathematical modeling. 相似文献
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Summary Life stages of the primitive Australian ithomiine butterflyTellervo zoilus and its larval hostplant, the apocynaceous vineParsonsia straminea, were quantitatively assayed for pyrrolizidine alkaloids (PAs). PAs were found in all stages, mainly as N-oxides, being most concentrated in larvae and freshly-emerged adults. Although adults feed at various confirmed PA sources this probably does not compensate for losses, as wild-caught adults had considerably lower concentrations of PAs. The main alkaloid present in both freshly-emerged adults and in leaves of the host-plant was lycopsamine (1b), stored by butterflies in the N-oxide form. Its presence in higher proportion, in relation to intermedine (1a), in larvae, pupae and adults ofTellervo in relation to the host-plants suggests the inversion of intermedine to lycopsamine by the insects. No 14-member ring macrocyclic PAs were detected in either food-plant or butterflies. Several other PAs were found in wild-caught adults reflecting visits to other PA sources. PAs were also found in high concentrations in freshly-emerged individuals of the danaineEuploea core bred onParsonsia straminea. Wild-caughtDanaus affinis had high PA levels acquired from adult feeding. Freshly emergedEuploea raised onIschnocarpus frutescens andDanaus raised onIschnostemma carnosum (both PA-free) were preyed on by the orb weaving spiderNephila maculata, and showed no PAs. In all cases where PAs were present, most butterflies were liberated, usually cut out of the web unharmed, byNephila. The spider's response was not closely linked to PA concentration, however, and may also depend on hunger levels and previous experience with PA-containing butterflies. All control and other non-PA containing butterflies were consumed although rejection of some body parts of freshly-emergedDanaus affinis suggests that compounds other than PAs may be involved. 相似文献