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21.
Laser desorption mass spectrometry (LDMS) may be used for the detection and identification of dyes found in inks. Naturally-aged and artificially-aged blue and black ballpoint pen inks containing the cationic dye methyl violet were analyzed on paper. The average molecular weight of the dye sample was calculated from LD mass spectral data and plotted versus time. The resulting aging curves demonstrate that, as dye degradation increases, the average molecular weight of the dye decreases. Typical variables involved in ink aging, such as the type of paper and ink formulation, were investigated. Results show that these variables influence the rate of dye degradation. Furthermore, UV accelerated aging has been developed and tested as an alternative to thermal approaches.  相似文献   
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This paper uses a heretofore untapped source of information in the National Crime Survey (NCS) victimization data—the interviewer narratives—to explore school-related victimizations among adolescents. These narrative reports provide important information bearing on lifestyle and routine activity theories of victimization that is simply not available from the more familiar, highly structured portions of the NCS questionnaire. The NCS narratives suggest that a large proportion of school-related victimizations stems from peer interactions that occur in the course of routine daily activities and escalate into victimizations. Students represent pools of both potential offenders and potential victims who come in frequent contact with each other, often in the absence of capable guardians. However, rather than predatory, calculated attempts to harm, school-related victimizations among adolescents appear to consist primarily of bullying, injured pride, and misguided mischief. The theoretical and methodological implications of this study are highlighted.  相似文献   
23.
Risk adjustment (RA) consists of a series of techniques that account for the health status of patients when predicting or explaining costs of health care for defined populations or for evaluating retrospectively the performance of providers who care for them. Although the federal government seems to have settled on an approach to RA for Medicare Advantage programs, adoption and implementation of RA techniques elsewhere have proceeded much more slowly than was anticipated. This article examines factors affecting the adoption and use of RA outside the Medicare program using case studies in six U.S. health care markets (Baltimore, Seattle, Denver, Cleveland, Phoenix, and Atlanta) as of 2001. We found that for purchasing decisions, RA was used exclusively by public agencies. In the private sector, use of risk adjustment was uncommon and scattered and assumed informal and unexpected forms. The most common private sector use of RA was by health plans, which occasionally employed RA in negotiations with purchasers or to allocate resources internally among providers. The article uses classic technology diffusion theory to explain the adoption and use of RA in these six markets and derives lessons for health policy generally and for the future of RA in particular. For health policy generally, the differing experiences of public and private actors with RA serve as markers of the divergent paths that public and private health care sectors are pursuing with respect to managed care and risk sharing. For the future of RA in particular, its history suggests the need for health service researchers to consider barriers to use adoption and new analytic technologies as they develop them.  相似文献   
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Gas chromatography-mass spectrometry was used to compare gasoline samples obtained from different sources based on the difference in amounts of certain components found in the headspace of gasoline using target response data. Many suspected arson cases involve comparing an ignitable liquid extracted from fire debris to a liquid found in a suspect's possession to determine if they could have had a common source. Various component ratios are proposed for determining if an unevaporated gasoline sample could have originated from the same source as an evaporated gasoline extracted from fire debris. Fifty and 75% evaporated gasoline samples were both found to contain similar ratios of certain components when compared with its unevaporated source gasoline. The results of the comparisons in this study demonstrate that for cases involving gasoline that has been evaporated up to 50% and extracted from pine, it is possible to eliminate comparison samples as originating from the same source. The results of the 75% comparisons suggest it may be possible to apply the same type of comparison to cases involving 75% evaporated gasoline.  相似文献   
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This paper addresses research in the life sciences, responsible for significant national expenditures for scientific investigations funded by both the federal government and industry. Our investigation examines faculty members' involvement with industry in entrepreneurial ways that is, involved in translating their research into potentially marketable knowledge or products. First, this study examines whether there are differences in entrepreneurial behaviour between clinical and non-clinical faculty in the life sciences with industry relationships, and, second, to discover any linkage between entrepreneurship and secrecy or productivity in different ways for clinical and non-clinical faculty. The study is based on survey responses of a national sample of 4,000 clinical and non-clinical life sciences faculty in 49 U.S. research universities. The results show non-clinical faculty as more involved at the back end. The more entrepreneurial end of commercialization while clinical faculty are involved at the back end. The more entrepreneurial faculty (non-clinical) are more likely to be secretive about their research. Clinical faculty are less likely to have been denied access to research results or products. Entrepreneurial faculty are not less productive in their faculty roles. This investigation is preliminary in that it addresses one large area of academic research but excludes fields with longer historical relationships with industry.  相似文献   
29.
The death of a parent in childhood represents a profound psychological insult. Although a number of studies have examined rates of depression and anxiety in bereaved children, less attention has been given to understanding predictors of children's adjustment to the loss. Data are presented from 83 families with school-age children in which a parent had died of cancer in the preceding 18 months. The surviving parent and one randomly selected child completed individual interviews conducted by a clinician in the families' homes. Using multiple regression, potential predictors of children's psychosocial adjustment to parental death are examined and their relative importance is discussed. Among the predictors considered were child's age, child's gender, deceased parent's gender, time since death, length of illness, presence of siblings, and parental communication patterns. The child's perception of the surviving parent's level of openness in parental communication was found to be significantly correlated with lower levels of depressive symptoms and state anxiety in bereaved children. Boys reported lower levels of depressive symptoms than did girls, and older children reported lower levels of state anxiety than did younger children.  相似文献   
30.
Despite decades of critical reframings, policy and practice on prisoner (re)entry often remains situated within a framework of individual responsibility that fails to acknowledge the structural drivers of criminalization. Attending to individual symptoms rather than root social, political and economic causes, such approaches may ultimately reinforce the inequalities and injustices that fuel imprisonment. This article presents a case study of an alternative approach. It examines A New Way of Life Reentry Project, a nonprofit organization in South Los Angeles, California, that offers housing and support to women coming home from prison through a critical and holistic framework—one that attends simultaneously to the physical, mental and social contexts that shape lived experiences before, during and after prison. Drawing from 7 years of observation and participation, supplemented by ten in-depth interviews, I argue that a critical, holistic approach can have a significant positive impact for people returning home from prison.  相似文献   
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