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901.
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903.
While radio is America's most abundant medium, its content is characterized more by sameness than by diversity. Stations find it more profitable to duplicate mass appeal programming formats than to program to minority tastes. Such rational business decisions come at the expense of the listening audience which is given few formats from which to choose. The regulatory system, which speaks to the value of program diversity, has been unsuccessful in creating effective incentives to foster radio diversity. The article suggests a novel approach to radio regulation that combines economic incentives with new methods for identifying audience preferences such that a profit-maximizing radio industry would serve more tastes than are presently served.An earlier version of this paper was presented to the Mass Communication and Society Division of the Association for Education in Journalism, Boston, August 1980. 相似文献
904.
Using techniques derived from information theory, structural dimensions of adolescent self-images were studied. Within a sample of 58 adolescents, patients and normals, a variety of self-images were obtained using a specially designed Q-sort. The initial hypothesis predicted, on the basis of previous findings, that the idealized self-images would be more polarizedfor the patients. This hypothesis was only partiallyconfirmed. the self-idealization was significantly more polarized in the patient group. But the other two idealizations (those based on parental expectations) did not reflect a patient-normal difference. Rather, a significant three-way interaction of sex, age, and psychiatric status was found for these self-images, as well as for the current self-image. The consistent pattern in these three-way interactions was that late-adolescent boys polarized their self-images if they were in the normal group and had structurally complex (nonpolarized) self-images if they were in the patient group. The paper concludes by discussing the meaning of these findings. A framework for interpreting polarization is proposed and applied to the results. In addition, the notion of a Self-Image Profile is formulated and further elaborated. Finally, the relevance of these studies to other personality research and clinical observations is considered.This investigation was supported in part by a Research Scientist Development Award, Number K1-70-178, to S.T.H.Received M.A. in social anthropology from Harvard University and M.D. from Yale University. Candidate, Boston Psychoanalytic Institute, 1969-. Currently studying self-image and cognitive development in populations of normal and psychiatrically impaired adolescents, from individual and group perspectives.Received M.D. from the University of Chicago; attended the Chicago Psychoanalytic Institute (1952–1954) and the Washington Psychoanalytic Institute (1954–1961). Presently on staff of Washington School of Psychiatry and Washington Psychoanalytic Institute. Major research interests are adolescence and the family and psychoanalytic-oriented treatment in conjunction with a ward or in-patient milieu therapy. Specific interest is identity formation of adolescence. 相似文献
905.
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907.
Neglect, defined as the failure of a caregiver to adequately provide safety, food, clothing, shelter, education, protection, medical/dental care, and supervision for a child in his/her care, is a relatively uncommon but important cause of child mortality. A retrospective review of pediatric deaths (age 18 years or less) referred to the Medical University of South Carolina Forensic Pathology Office for autopsy over the past 25 years revealed 16 deaths due to some type of pediatric neglect. Cases were analyzed as to age, sex, race, cause and manner of death, autopsy findings, ancillary studies, past medical history, social/family history, and caregiver. Six cases of malnutrition/starvation and/or dehydration were identified, composing the most common cause of death in the neglect cases identified and the majority of the homicides due to neglect. Other deaths in which neglect contributed significantly included toxic ingestions (2 cases), hyper-/hypothermia (2 cases), unusual drowning/aspiration (4 cases), electrocution (1 case), and delayed/absent medical therapy (2 cases, including one of the previously mentioned ingestions). Of these additional cases, 7 were certified as accidental manner, 2 as natural, and 1 as a homicide. Cases which fell into a "gray zone" in which the appropriateness of invoking neglect was a matter of opinion or societal convention were excluded from the review; examples included conventional accidental drowning, choking on food or aspiration of foreign body, overlying/wedging during sleep, accidental hanging, and motor-vehicle traffic accidents (pedestrians, unrestrained passengers). The findings of this review reinforce the fact that malnutrition/starvation and dehydration compose the most common form of lethal pediatric neglect while highlighting less common forms of neglect and the difficulty of determining manner of death in cases in which neglect plays a more questionable role than in seemingly clear-cut malnutrition/starvation and dehydration cases. We demonstrate the typical victim and scenario that investigators will encounter in cases of fatal pediatric neglect, often a child under the age of 1 year who has been deprived of food and/or drink for some time, or an older, more independently mobile child who has not been adequately supervised. These children may or may not have a demonstrable prior history of maltreatment or (nonfatal) neglect, and review of medical records is an important part of the investigation. We additionally discuss key gross autopsy findings, appropriate specimen collection, helpful ancillary studies, microscopic findings of significance, potential mimickers of neglect, and other special considerations in cases of pediatric neglect. 相似文献
908.
Ancillary studies in amniotic fluid embolism: a case report and review of the literature 总被引:2,自引:0,他引:2
Marcus BJ Collins KA Harley RA 《The American journal of forensic medicine and pathology》2005,26(1):92-95
The incidence of amniotic fluid embolism during pregnancy is approximately 1/50,000 and has a mortality rate in excess of 80%. The postmortem diagnosis of amniotic fluid embolism can be challenging for forensic investigators and pathologists. At autopsy, usually signs of disseminated intravascular coagulation suggest an amniotic fluid embolism. A definitive diagnosis of amniotic fluid embolism cannot be made until ancillary studies are performed on the decedent's tissues. We report a case of a 37-year-old G3P2 white female who was 36 weeks gestation when her membranes spontaneously ruptured. She suddenly became breathless, went into cardiogenic shock, and died. The autopsy revealed gross and microscopic findings of amniotic fluid embolism, which was confirmed with ancillary studies consisting of special stains, immunohistochemistry, and a serum tryptase level. The authors hope this case report, including gross and microscopic autopsy findings with procedural and ancillary studies, and review of the literature will help investigators and pathologists in the diagnosis of amniotic fluid embolism. 相似文献
909.
This paper attempts to investigate the determinants of the capital structure of a sample of 972 listed companies on the Shanghai
Stock Exchange and Shenzhen Stock Exchange in China in 2003. Various theories, namely, the trade-off, pecking order and agency
theories, are deployed to explain and predict the signs and significance of each factor identified by Ragan and Zingales (1995)
and Booth et al. (2001). Furthermore, we include institutional shareholdings, including state agency shareholdings, state-owned
shareholdings and privately owned shareholdings, as corporate governance variables to examine the effects of corporate structure
on the debt financing behaviours. As well documented, we find that profitability is negatively related to capital structure
at a highly significant level. The size and risk of the firms are positively related to the debt ratio – but only in term
of market value measures of capital structure. The years of the companies being listed on stock markets are positively related
to capital structure, indicating the access of the firms to debt finance is more easily judged by book value. Tax is not a
factor in influencing debt ratio. Ownership structure has a negative effect on the capital structure. The firms with higher
institutional shareholdings tend to avoid using debt financing, a behaviour that can be explained by entrenchment effects.
A further classification of the institutional shareholders reveals that, among the three groups of institutional shareholding,
the state institutions, including state agency and state-owned institutions, were more averse to debt financing, particularly
for state-owned institutions. There is no strong evidence indicating debt-averse behaviour by domestic institutional shareholders. 相似文献
910.
Death by overlaying and wedging: a 15-year retrospective study 总被引:1,自引:0,他引:1
Collins KA 《The American journal of forensic medicine and pathology》2001,22(2):155-159
Overlaying, the accidental death by smothering caused by a larger individual sleeping on top of an infant, is a cause of death that has been documented for centuries. The hazard of death has been reported to be greater in infants less than 5 months of age but may occur in children up to the age of 2 years. When an adult or older child rolls on top of an infant, mechanical asphyxia results. The face may be pressed into the mattress or into the body of the sleeping adult or older child. The infant's air may be expressed, and he or she is unable to cry due to pressure on the thorax and the inability to inhale. Some pathologists and investigators believe that the victims of overlaying have no pertinent physical findings at autopsy and that any injury is indicative of inflicted trauma. Others believe that one may see contusions and abrasions from overlaying in and of itself. Wedging is another form of accidental mechanical asphyxia that may have negative autopsy findings. The prevalence of bruising, contusions, or facial and ocular petechiae is not clear. The author reviewed all pediatric forensic cases referred for autopsy to the Forensic Section of the Medical University of South Carolina/Medical Examiners' Office over the past 15 years, from 1985 to 1999. Of these, all cases of overlaying, cases listed as undetermined sudden infant death syndrome versus overlaying, and wedging were included. The cases were analyzed as to victims' age, sex, race, location/bedding, bed-sharer, and whether the bed-sharer was known to have ingested drugs or alcohol before sleep. Postmortem physical findings were also reviewed, particularly for documentation of contusions, abrasions, or facial or ocular petechiae. By clarifying not only the victim, bed-sharer, and scenario but also the presence or absence of physical findings in cases of overlaying, wedging, and other accidental asphyxia, we can better categorize these cases. 相似文献