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981.
What can Western powers do today to ease an eventual global power shift resulting from the rise of superpowers such as China? This paper suggests that part of the answer lies in the same power-binding institutions that allowed the US to rise post WWII without threatening its allies. Continuity in the rules of the global system during a great power transition would promote stability by reducing uncertainty, as well as the extent to which material power can be used coercively. I argue that current superpowers, the EU among them, have an interest in ensuring an equitable distribution of the gains from cooperation. While distributional issues are usually treated in normative terms, they take on very real, material meaning in the context of a great power transition. With this in mind, I look at three aspects of the current global institutional framework that would benefit from reform: international trade and aid, institutional design, and institutional proliferation. In all three cases, a more equal distribution of the gains from institutions today increases the odds that those institutional arrangements will remain in the future.  相似文献   
982.
Population Research and Policy Review -  相似文献   
983.
Employment and earnings of foreign-born scientists and engineers   总被引:1,自引:1,他引:0  
Population Research and Policy Review -  相似文献   
984.
This paper examines a wide variety of forms, and full histories, of family structure to test existing theories of family influences and identify needs for new theories. The focus is on links between childhood family structure and both completed schooling and risk of a nonmarital birth. Using a 27-year span of panel (PSID) data for U.S. children, we find that: (a) change is stressful, (b) timing during childhood is relevant, (c) adults other than parents are important, and (d) two more recently studied family structures (mother-with-grandparent(s) and mother-with-stepfather) do not fit the molds of existing theories. The findings suggest that new theories should consider allocation of resources and reasons people group into family structures. Received: 11 September 1998/Accepted: 27 March 2000  相似文献   
985.
In oncology, it may not always be possible to evaluate the efficacy of new medicines in placebo-controlled trials. Furthermore, while some newer, biologically targeted anti-cancer treatments may be expected to deliver therapeutic benefit in terms of better tolerability or improved symptom control, they may not always be expected to provide increased efficacy relative to existing therapies. This naturally leads to the use of active-control, non-inferiority trials to evaluate such treatments. In recent evaluations of anti-cancer treatments, the non-inferiority margin has often been defined in terms of demonstrating that at least 50% of the active control effect has been retained by the new drug using methods such as those described by Rothmann et al., Statistics in Medicine 2003; 22:239-264 and Wang and Hung Controlled Clinical Trials 2003; 24:147-155. However, this approach can lead to prohibitively large clinical trials and results in a tendency to dichotomize trial outcome as either 'success' or 'failure' and thus oversimplifies interpretation. With relatively modest modification, these methods can be used to define a stepwise approach to design and analysis. In the first design step, the trial is sized to show indirectly that the new drug would have beaten placebo; in the second analysis step, the probability that the new drug is superior to placebo is assessed and, if sufficiently high in the third and final step, the relative efficacy of the new drug to control is assessed on a continuum of effect retention via an 'effect retention likelihood plot'. This stepwise approach is likely to provide a more complete assessment of relative efficacy so that the value of new treatments can be better judged.  相似文献   
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989.
Summary This paper describes a series of experiments conducted to determine whySitophilus zeamais Mots. andSitotroga cerealella (Oliv.) could not survive together in maize cultures in the laboratory. The effect ofS. zeamais on different developmental stages ofS. cerealella was investigated. The presence of adultS. zeamais slightly affected moth copulation, egg laying and moth eggs in a mixed culture, but large numbers of developing moths inside maize grains were killed by the adult weevil through feeding on the grains. The major cause of elimination ofS. cerealella byS. zeamais from mixed cultures was therefore found to be damage to the immature moths in grain and such moth mortality increased as the developing moths became bigger in the grains. A weevil: grain ratio of approximately 1.4∶1 was found to be the critical weevil density at which the moth disappeared from the mixed cultures.  相似文献   
990.
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