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51.
Numerous accounts reveal that congressional leaders often secure “hip‐pocket votes” or “if you need me” pledges from rank‐and‐file legislators. These are essentially options on votes. Leaders exercise sufficient options—pay legislators to convert to favorable votes—when those options will yield victory. Otherwise, they release the options. A model shows that this optimal strategy for leaders produces many small victories, few small losses, and losses that are, on average, larger than victories. We find precisely these patterns, hence strong evidence for vote options, in Congressional Quarterly key votes from 1975 through 2001 and in non‐key votes from the 106th Congress (1999–2000).  相似文献   
52.
This concept paper presents a theory of environmental scarcity developed byHomer-Dixon. Homer-Dixon developed a model to describe the consequences of scarcity for sub-national violence in third world countries. This paper hasfour interrelated purposes. First, it presents the model of scarcity developedby Thomas Homer-Dixon in 1999. Second, it assesses the way in which the scarcity model contextualizes criminal justice and criminology research, andby extension, how research in crime and justice processes can broaden the scarcity model. Third, it applies elements of the model to the United States,a goal that represents a generalization of the model from third-world to first-world settings. Fourth, it presents a particular case, the migrationof African-Americans from the rural South to urban centers in the 1950s and1960s and consequent inner-city violence in the 1960s, that displays manyelements of the environmental scarcity model.  相似文献   
53.
In 1991 the FCC implemented a price cap plan for local exchange carriers' interstate access service designed to deal with the regulatory boundaries problem arising from the breakup of AT&T in 1984. The experience with the price cap plan demonstrates the difficulty of predicting productivity growth accurately and makes clear that regulators cannot depend upon a pure price cap plan to keep prices within a reasonable range of costs. With periodic reviews to readjust plan parameters, however, a price cap plan can maintain the rate-of-return close to the target rate-of-return without diminishing the price cap plan's incentives for efficient production. A simple method of recalculating the X-factor based on the rate-of-return over the previous three years worked well in simulations. If this procedure had been used over the price cap period 1991 to 2000, prices would have been 20 percent lower and expenditures on LECs' telecommunications service subject to a price cap would have been $3.8 billion lower.  相似文献   
54.
The adjustment problems associated with sexual abuse, physical abuse, psychological maltreatment, neglect, and witnessing family violence during childhood were examined in three studies. Study 1 demonstrated significant overlap between maltreatment types in parent reports (N = 50) of maltreatment experiences of their child aged 5–12 years. Parental sexual punitiveness, traditionality, family adaptability and family cohesion significantly predicted scores on 4 maltreatment scales and children's externalizing behavior problems. Level of maltreatment predicted internalizing, externalizing, and sexual behavior problems. In Study 2, significant overlap was found between adults' retrospective reports (N = 138) of all 5 types of maltreating behaviors. Parental sexual punitiveness, traditionality, family adaptability, and family cohesion during childhood predicted the level of maltreatment and current psychopathology. Although child maltreatment scores predicted psychopathology, childhood family variables were better predictors of adjustment. Study 3 demonstrated that child maltreatment scores predicted positive aspects of adult adaptive functioning (N = 95).  相似文献   
55.
This paper considers technology transfer from a holistic perspective, defining and integrating all essential elements. Technology, technology ownership, and technology transfer are defined to enable practical management of the value of technology as an organizational asset. Concepts from value-chain movement of technology in commercial product development are used to develop a complete, detailed vision of technology transfer across corporate boundaries. Lessons enable development of a productive technology-transfer function that will speed evolution of technology to product and enable creation of new wealth.  相似文献   
56.
57.
There is widespread concern that higher education is being compromised by being turned into a ‘commodity’ to be ‘consumed’. This article represents an initial attempt to explore the trends in both the UK and US, and considers how the law has responded to them. It argues, however, that there is an important distinction to be drawn between ‘commodification’ and ‘consumerism’. Education has always been a commodity to be bought and sold; the true danger lies in the move to a ‘rights-based’ culture where students (and politicians) see education merely as something to be ‘consumed’ rather than as an activity in which to participate. Whilst the law seems thus far to have been something of a bulwark against this movement, it remains an open question as to whether this will continue to be the case if HEIs do not themselves act more proactively in challenging this damaging view of higher education.  相似文献   
58.
Weit weg und mittlerweile doch sehr nah liegt die Antarktis, wenn es um Klima- und Umweltschutz geht. Forschung und Tourismus strapazieren den au?ergew?hnlichen Naturraum. Der Beitrag zeigt auf, mit welchen Steuerungsans?tzen Deutschland seinen Verpflichtungen zum Antarktisschutz gerecht werden will. Ausgehend von einigen Informationen über den 6. Kontinent (A.) werden die unterschiedlichen Interessenkonflikte rund um Nutzung und Schutz der Antarktis illustriert (B.). Im Anschluss daran wird der zugeh?rige internationale und nationale Rechtsrahmen kurz vorgestellt (C.), ehe verschiedene Facetten des deutschen Ausführungsgesetzes n?her beleuchtet werden (D.). Flankierend wird neben dem Ordnungsrecht eine gute fachliche Praxis in Form eines Leitfadens als Element nichtrechtlicher Steuerung genutzt (E.). Der Beitrag schlie?t mit Fazit und Ausblick (F.).  相似文献   
59.
采用生长试验、免疫放射分析和定量PCR方法,观察了生长猪血液中类胰岛素生长因子(IGF-I)及其结合蛋白(IGFBP3)数量的变化和IGF-I基因在肝中表达量的变化。结果显示, 每1 kg饲料中添加125-250 mg铜,能够上调IGF-I基因的表达量,显著提高猪的平均日增重,促进生长猪循环血液中IGF-I浓度的增加。试验结果证实,铜是通过促进生长激素-胰岛素样生长因子轴相关因子的合成和分泌来发挥促生长作用的。  相似文献   
60.
While the concepts of race and ethnicity have been abused historically, they are potentially invaluable in epidemiology and public health. Epidemiology relies upon variables that help differentiate populations by health status, thereby refining public health and health care policy, and offering insights for medical science. Race and ethnicity are powerful tools for doing this. The prerequisite for their responsible use is a society committed to reducing inequalities and inequities in health status. When this condition is met, it is irresponsible not to utilize these concepts.  相似文献   
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