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31.
Paul A. Lewis 《政治学》2002,22(1):17-23
Researchers in political science are devoting increasing attention to the ontological commitments of their theories – that is, to what those theories presuppose about the nature of the political world. This article focuses on a recent contribution to this 'ontological turn' in political science ( Sibeon, 1999 ). Tensions are identified in Sibeon's account of the causal interplay between agency and social structure. It is argued that these tensions can be resolved by reflecting explicitly on ontological issues, in particular the causal efficacy of social structure, using a particular approach to the philosophy of the social sciences known as critical realism. The value of such reflection for the explanatory power of political analysis is highlighted.  相似文献   
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In an era when everyone wants to be a millionaire, governments struggle to attract and retain highly qualified employees, making it more important than ever to understand what attracts people to the public service. Using contingency table analysis and logistic regression on the 1989 and 1998 General Social Surveys, we explore how individuals' demographic characteristics and the importance they place on various job qualities influence their preference for and employment in the public sector. Job security may still be the strongest attraction of government jobs, but high income and the opportunity to be useful to society also attract some Americans to the public service. Minorities, veterans, Democrats, and older Americans preferred public-sector jobs more than whites, nonveterans, Republicans, and younger Americans, who were otherwise similar. Women and college graduates were more likely than comparable men and less-educated respondents to have government jobs, but no more likely to prefer them. Overall, desire for government jobs declined markedly between 1989 and 1998.  相似文献   
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During fatal aviation accident investigations, biosamples from the victims are submitted to the FAA Civil Aeromedical Institute (CAMI) for drug analysis. In the process of one such analysis by CAMI, an unknown substance was found in a urine sample. Simultaneous screening by thin layer chromatography (TLC) and gas chromatography/FID (GC/FID) suggested the presence of pseudoephedrine. A subsequent routine confirmation analysis of a separate urine aliquot by GC Fourier transform infrared (GC/FTIR) and GC mass spectrometry (GC/MS) indicated that the retention times of the unknown substance matched with those of pseudoephedrine. However, its infrared and mass spectra were different--the -OH and -NH groups were missing, a C-O-C group was present, and the molar mass was 12 atomic mass units (amu) more than that of pseudoephedrine. A subsequent literature search suggested that ephedrine-like amines react with aldehydes to form oxazolidines. Therefore, the 12-amu increase could be accounted for by condensation of pseudoephedrine with formaldehyde. Since this aldehyde is present in various grades of methanol and ethyl acetate, and these solvents were used during the solid-phase extraction, 3,4-dimethyl-5-phenyl-1,3-oxazolidine was synthesized by using (+)-pseudoephedrine HCl and formaldehyde. The analytical findings of the synthesized compound were consistent with those of the unknown interfering substance, confirming that it was the oxazolidine. Aldehyde contaminants in solvents or specimens can transform drugs of interest and may result in misidentification of a compound originally present in specimens. Therefore, chemicals used in analyses should be of the highest available purity, and a multi-analytical approach should be adopted to maintain a high degree of quality assurance.  相似文献   
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Medical examiners frequently rely on the finding of free morphine present in postmortem specimens to assist in certifying deaths associated with narcotics. In vitro hydrolysis of morphine-3-D glucuronide (M3DG) to free morphine was studied using variable specimen pH, initial degree of specimen putrefaction, storage temperature and time, and the effectiveness of sodium fluoride (NaF) preservation. Reagent M3DG was added to opiate-free fresh blood and urine and to autopsy-derived blood specimens. Reagent bovine glucuronidase was also added to certain specimens. Freshly collected and refrigerated NaF-preserved blood produced minimal free morphine, whereas four of five autopsy blood specimens produced free morphine from M3DG. Increased storage time, temperature, and initial degree of putrefaction resulted in greater free morphine generation despite the absence of viable bacteria. Hydrolysis occurring during specimen storage can generate free morphine from M3DG and may result in erroneous conclusions in certifying narcotic deaths.  相似文献   
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Thirty Black women activists within different age categories, from varied educational and occupational backgrounds, and representing Black women's organizations from different regions of the U.S. were interviewed to determine their views on the meaning and effect of the UN Decade for Women on the lives of Black American women. Their responses to questions about the Decade indicate that the masses of Black women are poorly informed or totally uninformed about the UN Decade for Women. And, among that segment of the Black female population which is well informed about the Decade, positive views on the benefits of the Decade for Black women correlate strongly with employment in a national women's organization or governmental agency dealing with women's issues, and personal involvement in UN Conferences. Many Black women feel that the opportunity to network with third-world women is the major benefit that Black American women gained from the Decade. They also feel that American racism and class bias effectively prevent equitable implementation of a national plan of action to improve the status of women in the United States.  相似文献   
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