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81.
Gifted adolescents: An analysis of their psychosocial development   总被引:1,自引:0,他引:1  
A model for viewing adolescent psychosocial development is outlined. The model assumes that basic changes in adolescents' biological, cognitive, and social capacities reciprocally interact with the social settings of the family, peer group, and school/work to influence transformations in six areas of psychosocial development (attachment, friendship, sexuality, achievement, autonomy, and identity). The model is then used as a framework for reviewing literature regarding gifted adolescents' psychosocial adjustment. On the whole, the literature provides a positive view of the psychosocial adjustment of gifted adolescents. While adjustment problems seem to exist in certain areas (e.g., friendship), unequivocal conclusions cannot be drawn because of methodological limitations and the narrow scope of existing research.  相似文献   
82.
83.
From 1991 to 2009, the fraction of Medicaid recipients enrolled in HMOs and other forms of Medicaid managed care (MMC) increased from 11 percent to 71 percent. This increase was largely driven by state and local mandates that required most Medicaid recipients to enroll in an MMC plan. Theoretically, it is ambiguous whether the shift from fee‐for‐service into managed care would lead to an increase or a reduction in Medicaid spending. This paper investigates this effect using a data set on state‐ and local‐level MMC mandates and detailed data from the Centers for Medicare and Medicaid Services (CMS) on state Medicaid expenditures. The findings suggest that shifting Medicaid recipients from fee‐for‐service into MMC did not on average reduce Medicaid spending. If anything, our results suggest that the shift to MMC increased Medicaid spending and that this effect was especially present for risk‐based HMOs. However, the effects of the shift to MMC on Medicaid spending varied significantly across states as a function of the generosity of the state's baseline Medicaid provider reimbursement rates.  相似文献   
84.
Indian snakeroot (Rauvolfia serpentina) is a valuable forest product, root extracts of which are used as an antihypertensive drug. Increasing demand led to overharvesting in the wild. Control of international trade is hampered by the inability to identify root samples to the species level. We therefore evaluated the potential of molecular identification by searching for species‐specific DNA polymorphisms. We found two species‐specific indels in the rps16 intron region for R. serpentina. Our DNA barcoding method was tested for its specificity, reproducibility, sensitivity and stability. We included samples of various tissues and ages, which had been treated differently for preservation. DNA extractions were tested in a range of amplification settings and dilutions. Species‐specific rps16 intron sequences were obtained from 79 herbarium accessions and one confiscated root, encompassing 39 different species. Our results demonstrate that molecular analysis provides new perspectives for forensic identification of Indian snakeroot.  相似文献   
85.
Slimming cactus (Hoodia), found only in southwestern Africa, is a well‐known herbal product for losing weight. Consequently, Hoodia extracts are sought‐after worldwide despite a CITES Appendix II status. The failure to eradicate illegal trade is due to problems with detecting and identifying Hoodia using morphological and chemical characters. Our aim was to evaluate the potential of molecular identification of Hoodia based on DNA barcoding. Screening of nrITS1 and psbAtrnH DNA sequences from 26 accessions of Ceropegieae resulted in successful identification, while conventional chemical profiling using DLI‐MS led to inaccurate detection and identification of Hoodia. The presence of Hoodia in herbal products was also successfully established using DNA sequences. A validation procedure of our DNA barcoding protocol demonstrated its robustness to changes in PCR conditions. We conclude that DNA barcoding is an effective tool for Hoodia detection and identification which can contribute to preventing illegal trade.  相似文献   
86.
Abstract

In the absence of physical evidence, investigators must often rely on offence behaviours when determining whether several crimes are linked to a common offender. A variety of factors can potentially influence the degree to which accurate linking is possible, including the similarity coefficient used to assess across-crime similarity. The current study examines the performance of two similarity coefficients that have recently been compared to one another, Jaccard's coefficient (J) and the taxonomic similarity index (Δs), using samples of two crime types, serial homicide (N=237) and serial burglary (N=210). In contrast to previous research, the results indicate that Δs does not significantly outperform J with respect to linking accuracy. In addition, both coefficients lead to higher levels of linking accuracy in cases of serial homicide compared to serial burglary. Potential explanations for these findings are presented and their implications are discussed.  相似文献   
87.
In this meta‐analytic study, we looked at all empirical studies that examined the effectiveness of court‐affiliated divorcing parents education programs (DPEs). Overall, we found that DPEs were generally effective. Nineteen studies with a DPE treatment group and no‐treatment control group had an overall significant moderate positive effect (d= .39); those who participated in DPEs were about 50% better off in terms of program outcomes compared to those who did not participate. The studies examined five specific outcomes: co‐parenting conflict, parent‐child relationships, child well‐being, parent well‐being, and relitigation; with most of these specific outcomes we found significant moderate effects ranging from d= .19–.61. However, there were important methodological limitations in this body of research, which are discussed. While more research is needed to confirm the positive potential of DPEs, we probably know enough to justify continuing and even increasing support for this recent social policy innovation.  相似文献   
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