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851.
852.
This article provides a new maximum-likelihood estimator forselection models with dichotomous dependent variables when identicalfactors affect the selection equation and the equation of interest.Such situations arise naturally in game-theoretic models whereselection is typically nonrandom and identical explanatory variablesinfluence all decisions under investigation. When identicalexplanatory variables influence selection and a subsequent outcomeof interest, the commonly used Heckman-type estimators identifyfrom distributional assumptions about the residuals alone. Whenits own identifying assumption is reasonable, the new estimatorallows the researcher to avoid the painful choice between identifyingfrom distributional assumptions alone and adding a theoreticallyunjustified variable to the selection equation in a mistakenattempt to "boost" identification. The article uses Monte Carlomethods to compare the small-sample properties of the estimatorwith those of the Heckman-type estimator and ordinary probit.  相似文献   
853.
Prostitute for a good reason: stars and morality in Egypt   总被引:2,自引:0,他引:2  
“Prostitute for a Good Reason. Stars and Morality in Egypt” introduces briefly the history of Egyptian film industry, its current star system and the general evaluation of stars on the artistic and moral level. It examines whether and to what extent Egyptian stars may attain a quasi-mythical power and the kind of moral concepts that are conveyed through them. Hence, it touches on the process of how Egyptian audiences are inclined to read mass-mediated messages. In this context the study refers to the phenomenon of veiling that spread among actresses during the early 1990s and tries to relate it to relevant ideological tensions at work. Consequently, the study investigates the position of actresses, primarily top star Nadia al-Gindi. Her image and film persona seem to indicate a very specific interaction between prevalent ideological and moral concepts of different origins including Islamism and modernism on the one hand and cultural taboos of sexuality and power on the other.  相似文献   
854.
Don't lose sleep     
Allen E 《Time》2001,157(14):83
  相似文献   
855.
This paper directs itself to the impact of American social science on the writings of Alva and Gunnar Myrdal on the role of education and social science in modern industrial democracy. After a brief sketch of the Myrdals' role in the development of Swedish welfare reforms and of their intellectual contacts in the United States during the 1930's, the paper outlines four theoretical dilemmas of modernity to the solution of which education and social research was seen to contribute: the relationships between facts and values, the individual and the collective, child rearing and social change, and theory and practice. The paper concludes by tracing the articulation of these themes in the Social Democratic Party school reform proposals of 1948.  相似文献   
856.
We report here the results of mtDNA analysis of remains exhumed in July, 1995 from Mt. Olivet Cemetery in Kearney, Nebraska, that are thought to be those of Jesse James. The remains were poorly preserved, presumably due to wet and slightly acidic soil conditions, and insufficient DNA for analysis was obtained from two bone samples. However, two of four teeth, and two hairs recovered in 1978 from the original burial site on the James Farm, did yield reproducible mtDNA sequences. These mtDNA sequences from the teeth and hairs were all identical, suggesting that they came from the same individual; furthermore, this mtDNA sequence was identical to mtDNA sequences determined from blood samples from two maternal relatives of Jesse James. Therefore, either the remains are indeed those of Jesse James, or they are from an unrelated individual who, by chance, happens to have the same mtDNA sequence. To assess the probability that an unrelated individual would have the same sequence, we searched the forensic mtDNA database, and found that this sequence does not appear among the 2426 mtDNA sequences therein. Hence, the mtDNA analysis supports the identification of the exhumed remains from Mt. Olivet Cemetery as those of Jesse James.  相似文献   
857.
Two species of blow flies (Diptera: Calliphoridae) were reared on tissues from rabbits administered different dosages of morphine. These species, Protophormia terraenovae and Calliphora vicina are among the first wave of insects colonizing a dead body. Two series of 3 rabbits were given dosages of 10, 20, and 40 mg/h of morphine over a 3 h period via ear artery perfusion. A morphine blood level plateau was attained after 1 h of perfusion. Two other rabbits were used as controls. Samples of tissues collected from rabbits using a coelioscopic technique were determined to have morphine concentrations similar to those encountered in human overdoses and were correlated with dosages of morphine administered. All samples from control rabbits were negative for morphine. Larvae and puparia of both species were regularly collected from each rabbit for toxicological analysis. Concentrations of morphine in larvae reared on rabbit carcasses containing morphine were significantly lower than concentrations found in the tissues. There was a decrease in concentration in morphine observed in transition from feeding 3rd instar larva to puparium. A correlation between larval concentration and tissue concentration was found only in feeding 3rd instar larvae.  相似文献   
858.
859.
The nature and extent of the use of blank pistols in Hamburg (according to the Hamburg crime statistics about 300 to 400 such cases per year; 34 cases involving head and neck wounds from 1989 to 1999 were investigated at our institute; among these 8 suicides, no homicide) as well as patterns of injuries caused by close distance blank pistol shots were analysed. 7 of these cases are described in detail. The results of our studies corroborate the warning statements made by many criminological and medico-legal experts regarding the danger inherent in these allegedly harmless weapons. Blank cartridge pistols can, when shot from a close distance, cause most severe injuries involving penetration into body cavities and bodily organs (especially in the head and neck), and even perforation of the skull. Therefore, we call for a much stricter control of weapons of this kind.  相似文献   
860.
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