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771.
772.
Davis  Douglas D.  Reilly  Robert J. 《Public Choice》1999,100(1-2):31-38
Nitzan's (1991) analysis of differential sharing rules in a collective rent-seeking setting is reconsidered. Two groups, each with more than one member, are presumed to use different linear combinations of two sharing rules, one based on an equal-division of the prize, and the other on each member's relative effort. We show that an equilibrium always exists for this type of game, and then characterize the equilibrium. Our result is contrary to Nitzan's claims that (a) in the general case an equilibrium often does not exist, and (b) an equilibrium never exists when the groups use the polar extreme rules.  相似文献   
773.
Differential extraction is an efficient method to separate sperm cells from epithelial cells. A manual Chelex®-100 based method is used at the Swedish National Laboratory of Forensic Science, SKL. The Differex™ System (Promega) uses a Proteinase K digestion of epithelial cells followed by centrifugation and phase separation. The sperm- and epithelial fractions are further purified with DNA IQ™ System (Promega) or with phenol/chloroform. The Differex™ System in combination with DNA IQ™ System were evaluated and compared to the Chelex®-100 method used routinely. After modifications, the Differex™ System gave comparable results to the Chelex®-100 method. The modifications included additional Proteinase K and DTT, longer incubation time and additional steps when removing the solid support from the Digestion Solution. In the Chelex®-100 based method microscopic examination is done on the sperm pellet in a total volume of 50 μl. It was not possible to do a microscopic examination in less than 100 μl using the Differex™ System. Additionally the sperms were in clusters of epithelial cell debris. Microscopic examination is an important part of the differential extraction at SKL. Therefore, the Differex™ System will not be implemented at our laboratory.  相似文献   
774.
Why a combatant command for Africa? I argue that AFRICOM was formed to implement the U.S. national security strategy that seeks to strengthen states and eliminate ungoverned space, as well as establish relationships with African states that offer a means to greater state stability and foster economic development. In so doing, it counters global jihadist by denying them haven among weak governments or in ungoverned areas. It protects U.S. interests in resources by helping governments become more stable. And it competes with the Chinese approach that could worsen the status quo of ineffective states and ungoverned space. Indeed, the U.S. approach of increasing state effectiveness makes African countries less susceptible to the problems that may arise from the Chinese approach and so serves China's interests in access to natural resources.  相似文献   
775.
776.
Stamp marks are used as a unique identification for a range of items, but these can be erased for criminal activities. Erased marks can sometimes be recovered by etching or magnetic means. The present study looked at the application of Fry's reagent to recover erased marks from steel. The investigation also demonstrated that Fry's reagent can deteriorate on storing and will require a longer etching time. The effect of different applied forces of stamping was investigated, and the depth of the underlying deformation was determined by etching after varying degrees of metal removal. The amount of metal needing to be removed depends on the force applied to the die. Metal removal also affects the time needed for recovery. The underlying structural change remains as a hidden identification mark, and could potentially be used by manufacturers as an unseen identifier. A model for the underlying deformation is proposed.  相似文献   
777.
A fraction of SIDS cases have death delayed by successful CPR, yet they have not been compared to SIDS cases which were found dead or not successfully resuscitated. Our aims were to: (1) determine the percent of SIDS cases in the San Diego SIDS Research Project database for whom death was delayed by CPR and subsequent life support; (2) compare demographics, circumstances of death and autopsy findings of delayed death SIDS cases (delayed SIDS) with those whose deaths were not delayed (non-delayed SIDS); (3) examine the evolution of pathologic changes in delayed SIDS as a function of survival interval. A retrospective 15-year population-based study of 454 infant deaths attributed to SIDS revealed 29 delayed SIDS cases (Group I) and 425 non-delayed SIDS cases (Group II). Group I cases were significantly older than Group II cases (mean age 132 days vs. 102 days and p<0.0001). Eighty-nine percent of the Group I cases were discovered between 08.00 and 19.59 h; none were found between 00.00 and 07.59 h, compared to 38% of the Group II cases. Group I infants were found significantly more often away from home (at daycare, or at the home of a relative, friend, or baby sitter) than Group II infants (45% vs. 25%, p<0.05). There were no differences between groups with regard to gender, gestational age, type of delivery, bed sharing, URI within 48 h of death, ALTEs, a history of referral to child protective services, body position when placed or found, or face position when found. Pathologic changes were semiquantitatively evaluated; findings were characteristic of anoxic-ischemic injury that generally became more severe with increasing survival intervals. Anoxic-ischemic brain injury was the immediate cause of death in all delayed SIDS cases. Aspiration of gastric contents was identified in Group I cases surviving less than 48 h and was the likely etiology of acute bronchopneumonia occurring in 83% of the Group I cases. We did not identify factors that would reliably predict which SIDS cases might be discovered soon enough to allow earlier and more effective CPR and survival without permanent brain injury.  相似文献   
778.
The incarceration of young people is a growing national problem. Key correlates of incarceration among American youth include mental health problems, substance use, and delinquency. The present study uses a statewide sample of incarcerated youth to examine racial differences in African American and Caucasian juvenile offenders' outcomes related to mental health, substance use, and delinquency. The data indicate that relative to Caucasian offenders, African American offenders report lower levels of mental health problems and substance use but higher levels of delinquent behavior such as violence, weapon carrying, and gang fighting. The data further reveal that African American offenders are more likely than Caucasian offenders to be victims of violence and to experience traumatic events such as witnessing injury and death. Recognition of these patterns may help to improve postrelease services by tailoring or adapting preexisting programs to patterns of risk factors and their relative magnitudes of effect.  相似文献   
779.
The associations between intimate partner violence (IPV) and mental health among adolescent and young adult mothers were compared. The sample was drawn from the Fragile Families and Child Wellbeing Study and participants were 672 mothers between the ages of 14 and 21. IPV was significantly positively associated with both depression and anxiety among young adult mothers. However, these associations were not found among adolescent mothers. In addition, IPV and marital status were significantly related among young adult mothers, but not adolescent mothers. Results suggest that IPV may have different consequences during different parts of the life course, or that mental health symptoms may be reported only later in life.
Christina B. GeeEmail:
  相似文献   
780.
Despite the fact that patients with mild traumatic brain injuries (TBI) are commonly encountered in clinical practice, there are numerous myths surrounding their diagnosis, assessment, and outcome. The purpose of this paper is to review some of the more common myths related to mild TBI including: (a) there is no Miserable Minority; (b) meta-analytic studies have proven that patients with mild TBI do not experience persistent deficits; (c) personality tests can reliably capture psychological problems in patients with a mild TBI; (d) findings from the sports concussion literature can be directly applied to clinical patients; and (e) in the absence of loss of consciousness, the diagnosis of a mild TBI is uncertain.  相似文献   
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