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The concentrations of ten elements in 209 unrelated glass specimens received as evidence were used to assess the frequencies of errors of false association (Type II errors) using several comparison criteria at specified significance levels (Type I errors). Pairwise comparisons of the samples using either the equal-variance t-test or Welch's modification (unequal variances) result in a small number of errors of false association, even when adjusting the significance level (Bonferroni correction) for multivariate comparisons. At the 95% confidence level (overall Type I error of 0.05, or individual element comparison error of 0.005), only two Type II errors are made in 21736 comparisons (0.009%) when using the equal-variance t-test for comparison of sample means. In this study, the range overlap test using three replicate measurements per specimen results in no errors of false association. Most specimen pairs in this data set are readily discriminated either by differences in the concentrations of several elements or by an extremely large difference in the concentrations of one or more element. 相似文献
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Steinhauer JR Volk A Hardy R Konrad R Daly T Robinson CA 《Journal of forensic sciences》2002,47(1):221-223
Ketosis occurs in ketoacidosis or malnourishment. When either is suspected in relation to a death, it may be important to analyze for ketosis at autopsy. We encountered a case where starvation was suspected in a deceased nursing home resident, where the body had been embalmed prior to autopsy. Gas chromatography (GC) was unable to separate acetone from formaldehyde, a component of embalming fluid. The Acetest is a simple test that can detect acetone and acetoacetate in body fluids. We validated the Acetest with GC on vitreous. The Acetest and GC were consistent except at very low levels of acetone or acetoacetate. The sensitivity of the Acetest for acetoacetate in vitreous was 10 mg/dL, consistent with early starvation. Significant interference from embalming fluid did not occur. The Acetest was negative in the described case. The Acetest is a simple and useful test for the detection of ketosis in embalmed autopsies. 相似文献
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China's rapidly growing motor vehicle fleet is changing the makeup of its urban atmosphere. While the two major problem pollutants historically have been particulates and sulfur dioxide, the growth in the number of automobiles has generated substantially increased levels of nitrogen dioxide (NO2). This paper examines and values the mortality health effects (reduced premature deaths) from cleaning up these three pollutants. Findings indicate that valued gains from reduced air pollution mortality can average 3% of a city's GDP. Moreover, the growing auto fleet may generate a ten-fold increase in NO2-based mortality costs and offset other, ongoing cleanup efforts in many Chinese cities. Specifically, the paper explores how the increasing number of automobiles might diminish or offset environmental cleanup activities focused upon particulate and sulfur dioxide pollution. 相似文献
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Robert S. Ross 《当代中国》2006,15(48):443-458
Taiwan is a revisionist power. Its independence movement challenges a vital status-quo interest of mainland China's opposition to a de jure Taiwan declaration of independence and maintaining, however ambiguously, Taiwan's commitment to the ‘one-China’ formulation. Why is it that a small and vulnerable island off the coast of a great power has continued to challenge the vital interest of that great power and risk war? Adopting a ‘levels of analysis’ approach to Taiwan's mainland policy, this paper addresses this question by examining four prevalent explanations for Taiwan's revisionist diplomacy: (1) the mainland deterrent is ineffective, reflecting Taiwan doubts about either mainland capabilities or mainland resolve to wage a retaliatory war; (2) in an example of the security dilemma in alliance politics, US commitment to Taiwan, although aimed at deterring PRC use of force, encourages Taiwan to challenge the status quo because the Taiwan leadership is confident of US intervention and US ability to defend Taiwan; (3) because of the development of a ‘Taiwan identity’ and of corresponding domestic political pressures, the Democratic Progressive Party has been compelled to adopt a pro-independence policy; (4) Chen Shui-bian has a personal commitment to Taiwan independence and has been willing to challenge the mainland's interest in one-China, despite risk of heightened conflict and regardless of domestic political considerations. 相似文献
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