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81.
The views expressed here are solely those of the author and do not represent the position of any U.S. government agency.  相似文献   
82.
Since 1958 NASA has invested approximately $3.7 billion in life sciences R&D in the support of the successful human space flight program. There are numerous studies documenting the spin-off technologies that can be traced to NASA research and development activities. Most of these studies describe the technologies and their uses; however only a few measure the economic impact of the spin-offs and most of these are benefit/cost studies that tend to overstate benefits or underestimate costs. This study takes a different approach, measuring only economic impacts to the companies that developed successful spin-off products from NASA life sciences investments. A personal interview was conducted with each company and the benefits are conservatively estimated as the value-added by the NASA technology to the company's output and the amount of additional private R&D stimulated by the NASA R&D.This pilot study of fifteen companies, using a very conservative measurement technique, found a large return to companies that have successfully commercialized NASA life sciences spin-off products. Value-added benefits totaled over $3.7 billion in life sciences R&D in the support of the successful human space flight program. There are numerous studies documenting the spin-off technologies that can be traced to NASA research and development activities. Most of these studies describe the technologies and their uses; however only a few measure the economic impact of the spin-offs and most of these are benefit/cost studies that tend to overstate benefits or underestimate costs. This study takes a different approach, measuring only economic impacts to the companies that developed successful spin-off products from NASA life sciences investments. A personal interview was conducted with each company and the benefits are conservatively estimated as the value-added by the NASA technology to the company's output and the amount of additional private R&D stimulated by the NASA R&D.This pilot study of fifteen companies, using a very conservative measurement technique, found a large return to companies that have successfully commercialized NASA life sciences spin-off products. Value-added benefits totaled over 1.5 billion and a NASA R&D total investment in these 15 technologies of 64 million was found to stimulate an additional64 million was found to stimulate an additional 200 million in private R&D.  相似文献   
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Behaviors developed in adolescence influence health later in life. The purpose of this study was to investigate the frequency of health care provider's discussion of health behaviors with overweight and non-overweight adolescents and identify demographic and health behaviors related to exercise, hours of television viewing, and weight issues associated with these discussions. A Cross sectional survey of urban adolescents was conducted. Trained interviewers administered surveys over a three month period in 2001 at an urban academic pediatric and adolescent clinic. The 252 adolescents surveyed had a mean age of 15 with 49% categorized as being at risk for overweight/overweight and 51% as normal weight using the CDC percentiles for BMI. While 16% of the adolescents reported that their physician or nurse discussed the amount of television they watched, rates of discussion related to exercise (58%), and weight (54%) were much higher. In multivariate analyses, health care provider discussions with adolescents regarding exercise were more common for overweight (O.R.=2.42, 95% C.I. [1.28–4.57]) and at risk for overweight (O.R.=1.98, 95% C.I. [1.03–3.81]) adolescents, whereas physician discussion of television viewing was not associated with weight. Discussions of weight were more common for female (O.R.=2.18, 95% C.I. [1.21–3.95]), African-American (O.R.=2.53, 95% C.I. [1.40–4.57]), and overweight (O.R.=3.92, 95% C.I. [1.97–7.81]) adolescents. Even after adjusting for weight, race and gender strongly influenced the frequency of discussions about weight in physician offices. Although health care providers frequently address weight and exercise with adolescents, more discussions related to sedentary behaviors such as television viewing may be warranted to address adolescent obesity.Received PhD in Epidemiology from University of California, San Diego. Research interests include smoking prevention and cessation among adolescents and health promotion interventions.Received MD from University of Missouri-Kansas City and MPH from Johns Hopkins University. Research interests include health services research and research in support of measurable, systematic improvements in the quality of medical care.Received medical degree from Christian Medical College, Punjab, India and Master of Public Health from University of Kansas School of Medicine. Research interests include diet and physical activity behaviors, role of the environment in obesity and obesity prevention, especially among children and adolescents.Received MBBS from Allama Iqbal Medical College, Punjab University, Lahore, Pakistan and MPH from University of Kansas Medical Center. Research interests include smoking cessation, database design, implementation, data management and analysis, and use of information technology in health care settings.Director, Cancer Prevention, Control, and Population Sciences, Kansas Cancer Institute. Received MD/MPH from Tulane University and MS from Harvard School of Public Health. Research interests include disparities in healthcare; smoking cessation among underserved populations, specifically African Americans; diet, nutrition, obesity, and physical activity.  相似文献   
84.
Political knowledge is a powerful predictor of political participation. Moreover, what citizens know about the political system and its actors is a central aspect of informed voting. This article investigates how and why political knowledge varies between citizens. The analysis is comparative and based on data from the Comparative Study of Electoral Systems. At the micro level, the results confirm results from national surveys – specifically that education explains what citizens know about politics. It is found in a contextualized analysis, however, that the effect of education varies with the country's degree of economic redistribution. In more egalitarian countries, political knowledge is less contingent on education attained than in more inegalitarian countries. Similarly, education seems to have a stronger effect in countries with majoritarian electoral systems compared to countries with proportional systems.  相似文献   
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This aticle analyses China's housing reform against the background that a new housing policy has been implemented since 1988. The crucial point of the 1998 housing policy package is to stop the allocation system of state‐subsidized public housing. By changing this rule of the game, a major institutional obstacle to housing reform will be removed, and some unfeasible policy measures become feasible within the new institutional context.  相似文献   
89.
In “Reconciling voters' behavior with legislative term limits,” Dick and Lott argue that since more senior representatives are better at rent-seeking, there is an inefficient tendency to re-elect incumbents. In their model, term limits are preferred collectively by constituencies, even though no constituency would independently oust its incumbent representative. However, many term limits are unilaterally self-imposed (in particular the 22nd amendment limiting presidents' terms to two), and their model cannot explain these limits. In this comment, I suggest that term limits may be self-imposed by risk-averse voters, who prefer cycling between left and right wing candidates to a once-and-for-all election that imposes a candidate of a single ideology on the entre electorate. The market failure that makes term limits helpful is that out of power minorities cannot bribe the median voter.  相似文献   
90.
In contrast to the belief that the 1995–1996 Taiwan Straits crisis was caused by the visit of the President of Taiwan to Cornell University, in fact, the post‐Mao ruling groups in Beijing made forcing early reunification with mainland China on Taiwan a top priority soon after assuming power in 1978. This new focus on Taiwan's reunification reflects a policy switch. It is not a continuation of Mao era policies. The switch is basic. It involves a profound change in the content of Chinese nationalism from Mao era nationalism, which is seen by its critics in China as insufficiently promoting the national interests of the Chinese people. The new, post‐Mao nationalism in China not only challenges Taiwan's autonomy, it also could endanger peace in the Pacific‐Asia region. Consequently, it is important to rethink the political dynamics at work in China and in the region if the parties involved hope to avoid a larger war.  相似文献   
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