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951.
Among the known causes of aircraft disasters, sabotage is perhaps the most terrifying and difficult to comprehend. Bombs have been exploded in at least 34 commercial aircraft, with the resultant loss of more than 300 lives. Motives for these acts include profit, the deaths of certain persons, and politics. On November 1, 1955, United Airlines Flight 629, bound to Denver-Portland, exploded and burned in flight near Longmont, Colorado, a few minutes after takeoff, with the loss of all 44 on board. Investigation revealed that the plane had been destroyed by the explosion of a bomb that had been placed in the rear luggage hold in Denver. Twelve days after the disaster, John Gilbert Graham, the son of one of the female passengers, was arrested and charged with murder. He reportedly admitted placing a time bomb on board the aircraft, apparently in order to collect $37,500.00 in life insurance that he had taken on his mother's life. Though he soon recanted, he was convicted of murder and was executed. The potential for additional such crimes remains.  相似文献   
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Public-goods dilemmas are characterized by conflicts between self-interest and the welfare of a group or society at large. Research has identified several factors that enhance cooperation in such dilemmas. However, less is known about how concern for distributive justice affects willingness to contribute in asymmetric public-goods dilemmas. To test the hypothesis that contributions to a common resource is related to perceived fairness, experiments were performed to investigate willingness to pay to the social service of child care in hypothetical societies. Experiment 1 aimed at replicating a previous survey study (Biel et al., 1997). Experiments 2 and 3 were extensions. In all three experiments subjects were asked to indicate how fair they considered different distributions of the quality of child care provided by their municipality. These distributions corresponded to the principles of equality, equity, and need. University students (32, 48, and 32 in the three experiments, respectively) served as subjects. Ratings of perceived fairness were positively related to willingness to pay. Other factors also positively related to willingness to pay included ability to pay, personal need, expected payment from others, and the number of households who had to contribute in order to maintain the quality. Furthermore, decreasing municipality size increased willingness to pay.  相似文献   
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Forensic investigations often demand a clear definition of secretor status. Lewis-typing of secretion stains may help to verify non-secretor results and to identify mixtures of secretions from Le (a-b-) persons and secretors (or non-secretors). Furthermore it gives an additional check on secretor status, determined by ABO-grouping. Few problems may arise, when testing prepared saliva or semen stains. Therefore our interest was focussed on the possibility of Lewis-typing in stains appearing in forensic case work such as cigarette tips, stamps and envelope flaps, semen stains and vaginal swabs, nasal secretion, sweat and urine stains. All stains with the exception of sweat and urine were successfully Lewis-typed. In saliva stains Lewis substances could be determined even after 5 years and in semen stains for at least up to 40 days.  相似文献   
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Reports of single-parent-child relationships characterized by child maltreatment have increased in recent years. The present paper discusses Belsky's child maltreatment/parenting model concerning parenting and the etiology of this problem. The model may serve as a source of conceptual unification of this risk in single-parent homes. It is proposed that the model also may have heuristic value in identifying highest risk single-parent families who warrant intervention.  相似文献   
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