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This essay seeks to extend current anthropological theorizing on emotion. Although anthropologists have convincingly established the specifically cultural status of emotion, recognition also of state (including sociopolitical institutions of nation-states) constructions of affect has been slow in coming. The present essay seeks to expand the emerging scholarly discourse on the emotions by examining the nexus among the role of the state in constructing a political ethos, the personal emotions of those who dwell in that ethos, and the mental health consequences for refugees. This analysis is intended as a bridge between analyses of the state construction of affect, on the one hand, and the phenomenology of those affects, on the other. To illustrate, I examine the state construction of affect and its traces in the narrative and clinical presentations of Salvadoran refugees in North America. The saliency of fear and anxiety among a group of psychiatric out-patients is framed by bodily experience, knowledge of illness, and the ethnopsychology of emotion within the context of chronic political violence and poverty. Distinctions between terror and torture, distress and disease are proposed as essential to an account of refugee experience. Future directions for the study of the state construction of affect are suggested.  相似文献   
134.
In this investigation, an attempt was made to identify the major urinary estrogen metabolites in the okapi by radioisotope infusion and by chromatographic separation procedures. The results suggest that the urinary estrogens are excreted in concentrations below the limit of sensitivity of conventional assay systems. In addition, a variety of contaminants with estrogenic immunoreactivity are present in okapi urine that are not necessarily correlated with follicular activity. A great proportion of circulating estrogen is eliminated in fecal material. However, the rate of elimination is slow, and the extraction procedures necessary to detect the metabolites are tedious, which would prevent the practical application of this procedure for monitoring follicular activity.  相似文献   
135.
This longitudinal study from Germany examined the dynamic progression of antisocial behavior in childhood and adolescence based on the social interactional model by Patterson, DeBaryshe, and Ramsey. It examined the link between antisocial behavior, social rejection, academic failure, and affiliation with deviant peers in a sample of 1,657 children and youths aged between 6 and 15 years who were studied at three measurement waves (T1 to T3) over a time period of about 5 years. Teachers rated the children on all variables, parents additionally provided ratings of antisocial behavior and social rejection. Latent structural equation modeling yielded the predicted positive paths from antisocial behavior at T1 to social rejection and academic failure at T2. As predicted, affiliation with deviant peers at T2 was positively associated with social rejection and academic failure at the same measurement point. Finally, affiliation with deviant peers at T2 significantly predicted antisocial behavior at T3.  相似文献   
136.
Ovarian activity in the female giraffe was evaluated during the nonfertile ovarian cycle and during the terminal stages of gestation. Progesterone metabolites, in the form of pregnanediol-3-glucuronide (PdG), were measured in daily random urine samples collected from four adult parous giraffes. The follicular phase averaged 4.0 ± 0.1 days in length (N = 12; range 3–5 days) and peak PdG levels in the postovulatory period averaged 30.9 ± 1.7 ng/mg Cr (N = 12). PdG levels during the latter half of gestation greatly exceeded average luteal phase levels, which is in contrast to domestic ruminants. Prior to parturition, a marked decline in PdG excretion was evident, which may be useful for anticipating this event. These data serve to elucidate ovarian function in the mature female giraffe and to provide information concerning the physiologic role of certain anomalous ovarian structures. In addition, observed similarities in the pattern of PdG excretion during the nonfertile cycles of the giraffe and the okapi indicate similar underlying physiologic processes.  相似文献   
137.

Background  

The melanocortin (MC) receptors have a key role in regulating body weight and pigmentation. They belong to the rhodopsin family of G protein-coupled receptors (GPCRs). The purpose of this study was to identify ancestral MC receptors in agnathan, river lamprey.  相似文献   
138.

Background

Estimating evolutionary rates for slowly evolving viruses such as papillomaviruses (PVs) is not possible using fossil calibrations directly or sequences sampled over a time-scale of decades. An ability to correlate their divergence with a host species, however, can provide a means to estimate evolutionary rates for these viruses accurately. To determine whether such an approach is feasible, we sequenced complete feline PV genomes, previously available only for the domestic cat (Felis domesticus, FdPV1), from four additional, globally distributed feline species: Lynx rufus PV type 1, Puma concolor PV type 1, Panthera leo persica PV type 1, and Uncia uncia PV type 1.

Results

The feline PVs all belong to the Lambdapapillomavirus genus, and contain an unusual second noncoding region between the early and late protein region, which is only present in members of this genus. Our maximum likelihood and Bayesian phylogenetic analyses demonstrate that the evolutionary relationships between feline PVs perfectly mirror those of their feline hosts, despite a complex and dynamic phylogeographic history. By applying host species divergence times, we provide the first precise estimates for the rate of evolution for each PV gene, with an overall evolutionary rate of 1.95 × 10-8 (95% confidence interval 1.32 × 10-8 to 2.47 × 10-8) nucleotide substitutions per site per year for the viral coding genome.

Conclusion

Our work provides evidence for long-term virus-host co-speciation of feline PVs, indicating that viral diversity in slowly evolving viruses can be used to investigate host species evolution. These findings, however, should not be extrapolated to other viral lineages without prior confirmation of virus-host co-divergence.  相似文献   
139.
The Ras GTPase-activating-like protein IQGAP1 is a multimodular scaffold that controls signaling and cytoskeletal regulation in fibroblasts and epithelial cells. However, the functional role of IQGAP1 in T cell development, activation, and cytoskeletal regulation has not been investigated. In this study, we show that IQGAP1 is dispensable for thymocyte development as well as microtubule organizing center polarization and cytolytic function in CD8(+) T cells. However, IQGAP1-deficient CD8(+) T cells as well as Jurkat T cells suppressed for IQGAP1 were hyperresponsive, displaying increased IL-2 and IFN-γ production, heightened LCK activation, and augmented global phosphorylation kinetics after TCR ligation. In addition, IQGAP1-deficient T cells exhibited increased TCR-mediated F-actin assembly and amplified F-actin velocities during spreading. Moreover, we found that discrete regions of IQGAP1 regulated cellular activation and F-actin accumulation. Taken together, our data suggest that IQGAP1 acts as a dual negative regulator in T cells, limiting both TCR-mediated activation kinetics and F-actin dynamics via distinct mechanisms.  相似文献   
140.
A primary focus of wildlife ecology is studying how the arrangement, quality, and distribution of habitat influence wildlife populations at multiple spatial scales. A practical limitation of conducting wildlife–habitat investigations in the field, however, is that sampling points tend to be close to one another, resulting in spatial clustering. Consequently, when ecologists seek to quantify the effects of environmental predictors surrounding their sampling points, they encounter the issue of using landscapes that are partially or completely overlapping. A presumed problem of overlapping landscapes is that data generated from these landscapes, when used as predictors in statistical modeling, might violate the assumption of independence. However, the independence of error is the critical assumption, not the independence of predictor variables. Nonetheless, many researchers strive to avoid such overlaps through sampling design or alternative analytical procedures and specialized software programs have been created to assist with this. We present theoretical arguments and empirical evidence showing that changing the amount of overlap does not alter the degree of spatial autocorrelation. Using data derived from 2 broad-scaled avian monitoring programs, we quantified the relationship between forest cover and bird abundance and occurrence at multiple landscapes ranging from 100 m to 24 km across. We found no clear evidence that increasing overlap of landscapes increased spatial autocorrelation in model residuals. Our results demonstrate that the concern of overlapping landscapes as a potential cause of violation of spatial independency among sampling units is misdirected and represents an oversimplification of the statistical and ecological issues surrounding spatial autocorrelation. Overlapping landscapes and spatial autocorrelation are separate issues in the modeling of wildlife populations and their habitats; non-overlapping landscapes do not ensure spatial independency and overlapping landscapes do not necessarily lead to greater spatial autocorrelation in model errors. © 2011 The Wildlife Society.  相似文献   
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