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981.
This study uses pairing of Mexican‐owned manufacturing firms and firms with direct United States investment, to examine the effects of ownership structure on firms’ performance and sources of technology. Results suggest that in terms of profitability, growth and export performance the Mexican firms were competing successfully during the period 1966–73. Furthermore, the basis for this strong posture by the Mexican manufacturers was not due to a heavy reliance on foreign technology imported through formal channels, but rather is linked with internal innovative activity and the use of domestic consultants.  相似文献   
982.

This article focuses on the measurement of embodied technological change. It develops the core-machinery approach to capital measurement, which is based on an engineering perspective on technological change. Using technical characteristics of different types of machinery, technical progress in the capital stock can be decomposed into incremental innovation in existing machinery and radical shifts to new technologies. The usefulness of this approach is illustrated by an analysis of embodied technological change in the Indonesian spinning and weaving industries. The core-machinery measure is compared with more traditional measures of the capital stock which are based on price information. Strengths, weaknesses and relevance of the new measure are discussed.  相似文献   
983.
It is often argued that agricultural factor markets in colonial India were underdeveloped, leading to inefficient resource use and slow agricultural development. However, there is little econometric evidence on these issues. This article outlines a model which incorporates the factor market imperfections discussed in the literature and tests the model against data from the Punjab. There is, in the statistical sense, evidence of resource misallocation; however, these effects are too small to be of much economic significance.  相似文献   
984.
985.
Book Reviews     
Jarol B. Manheim, All of the People all the Time: Strategic Communication and American Politics (New York: M.E. Sharpe, Inc., 1991), 255 pp. $25.00.

Harry C. Mansfield, Jr., America's Constitutional Soul (Baltimore, MD: Johns Hopkins Press, 1991), pp. 236.

Donald L. Horowitz, A Democratic South Africa? (Berkeley, CA: University of California Press, 1991), 293 pp. $24.95.  相似文献   
986.
In July 2000, the PRI (Institutional Revolutionary Party) lost the presidency of Mexico after 71 years of continuous rule. Research based on individual data obtained with surveys shows that important media effects occurred. Using aggregate data, in this article the author explores the effects of political advertising and media coverage on preferences during the Mexican presidential campaign. Data on voter preferences are taken from results of a trial ballot question in public opinion polls. Data on advertising are measured in gross rating points. Data on media coverage are taken from the monitoring of newscasts on the two major networks. OLS regression models are developed, with preferences as the dependent variable and campaigning differentials as the independent variables. Based on aggregate data, this research shows that in Mexico's 2000 presidential campaign, exposure to political communication led to persuasion, and news appears to have been more important than ads. Political communication was a unified process where ads and news presence acted together in a very interesting fashion, “bounding” each other in periods of major changes in preferences but with news effects prevailing over ads. Qualified news differentials accounted for 20% of the variance in preferences, and ad differentials accounted for 8%. This media effect occurred through a cumulative process where ads and news coverage acted together.  相似文献   
987.
Bath salts are new designer drugs with stimulant effects on the central nervous system. White or brown powder sold online and in mini‐marts under different brand names, bath salts can be used by injecting, snorting, smoking, or ingesting with food or drink. The case of a 30‐year‐old Caucasian male who developed acute psychosis within a few hours of injecting himself with bath salts is described. The patient was hospitalized with a complaint of hearing voices. The drug also induced in the patient a state of euphoria, increased energy level, along with decreased need for sleep and decreased appetite. The psychological effects of the bath salts subsided within a few hours of injection and his reality testing remained consistently intact over the next 3 days of hospitalization. This case brings to attention the fact that bath salts were legal throughout the United States until recently and is still not completely controlled. This report informs clinicians of harmful effects of bath salts, including severe agitation with possible rhabdomyolysis, psychosis, suicidal ideation, hypertension, tachycardia, and death.  相似文献   
988.
This study investigated and evaluated the safety margins of the continuous long duration (up to 30 min) effect of the TASER X26 waveform, using a Sus scrofa model. Long duration continuous stimulus has not been evaluated on humans or human surrogates prior to this study. Swine were used as models due to similarities with humans in their skin and cardiovascular systems. Very long duration was used to determine both exposure dose and possible adverse physiological effects of dose. The trial began with an application of 10 min, and subsequent animals received increasing exposure time up to a survived maximum duration of 30 min. At the onset of this work, it was hypothesized that there would be a time limit after which most animals would not survive consistent with increased dose response. However, this hypothesis was not supported by the experimental results. All animals (10 of 10) survived up to 3 min. Seven of the 10 animals survived up to a 10‐min exposure and 3 of 5 animals with a 30‐min target exposure survived the full exposure. Surviving animals were recovered and observed for 24 h, with no postrecovery deaths. This suggests that swine (based on physiology) will not experience a fatal event when exposed to the TASER X26 for a continuous 3 min. Conclusions regarding longer duration (10–30 min) are not as certain due to the small sample sizes at these time intervals.  相似文献   
989.
In the past, improvements in craniofacial reconstructions (CFR) methodology languished due to the lack of adequate 3D databases that were sufficiently large and appropriate for 3‐dimensional shape statistics. In our study, we created the “FACE‐R” database from CT records and 3D surface scans of 400 clinical patients from Hungary, providing a significantly larger sample that was available before. The uniqueness of our database is linking of two data types that makes possible to investigate the bone and skin surface of the same individual, in upright position, thus eliminating many of the gravitational effects on the face during CT scanning. We performed a preliminary geometric morphometric (GMM) study using 3D data that produces a general idea of skull and face shape correlations. The vertical position of the tip of the (soft) nose for a skull and landmarks such as rhinion need to be taken into account. Likewise, the anterior nasal spine appears to exert some influence in this regard.  相似文献   
990.
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