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More than a decade after NAFTA (North American Free Trade Agreement) entered into force, the environmental effects of agricultural trade liberalization in Mexico are still controversial, emerging, and not fully understood. This paper contributes to the literature that aims to explore trends in input use in the agricultural sector in Mexico during the post-NAFTA period among both commercial/industrial and traditional/rainfed farmers, and examines the influence of the national and multilateral institutional framework on these outcomes. We decompose the post-NAFTA agricultural production data into scale, technique and composition effects to estimate the impact that trade liberalization has had on the use of fertilizer and land use, two key agricultural inputs for which reliable aggregate data is available. We conclude that among commercial farmers patterns of crop type specialization and significant technological improvements have led to some declines in fertilizer use but they have been offset by growth in fertilizer use associated with growing agricultural output. Among traditional farmers increased output and specialization in land-intensive grain crops are contributing to an increase in land under cultivation and technological improvements show the potential, but not yet not the strength, to counteract these effects. We analyse the environmental institutional framework and rural development plans, observing that institutional weaknesses have, in several instances, reduced the environmental benefit of technique and composition effects. We conclude with recommendations about how the Mexican agricultural sector might reap the environmental benefits of international agricultural trade.  相似文献   
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The end of the twentieth century was marked by a sea change in global governance in the realm of intellectual property rights (IPRs). Whereas countries historically retained substantial autonomy with regard to what they defined as intellectual "property" and the rights granted to the owners of intellectual property, the 1990s witnessed the establishment of new global obligations regarding national practices. This paper focuses on the case of software "piracy" to assess the mechanisms by which the new global obligations for the treatment of IPRs are transmitted from the international to the national levels. We first consider a set of national-level factors that many scholars have shown to be important determinants of IPR policy. We then supplement the standard emphasis on domestic factors with an analysis of new transnational factors: countries' multilateral obligations under the World Trade Organization's (WTO) Agreement on Trade-Related Aspects of Intellectual Property Rights (TRIPS) and bilateral pressures from the United States to increase the protection of IPRs. Population-averaged panel data models are used to assess the effects of these national and transnational determinants on levels of software piracy in 80 countries from 1994 to 2002. Our results indicate that membership in the WTO and bilateral pressures from the United States—particularly pressures that offer reciprocal concessions—lead to substantial increases in levels of protection in rich and poor countries. There is, in short, a new international political economy of intellectual property.  相似文献   
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Law enforcement agencies and institutions of higher education have confronted increasing numbers of violent and destructive campus riots and disturbances over the past decade. Problematic is the fact that these riots typically have no underlying cause, other than students’ quest for excitement. Responding to gaps in the empirical literature about these events, this study used data from two waves of surveys to systematically examine those involved in a recurring problem event in a college town that was subject to a police crackdown. The analyses drew on survey responses from over eight hundred event participants in 2002 and 2003, and the results revealed that increased enforcement had a significant effect on crowd composition, including the gender and race of participants, repeat visitors, out-of-town participants, and perceptions about the subjects' overall experience. Implications for law enforcement and community strategies to decrease the size and destructiveness of such problem events are outlined.  相似文献   
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Eight homicidal youths were assessed for language disorders and psychiatric diagnoses using a battery of standardized language tests and the Diagnostic Interview for Children and Adolescents. Both language disorders and Diagnostic and Statistical Manual III-R psychiatric diagnoses were present in all subjects.  相似文献   
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