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贾谊是西汉初杰出的政论家,他提出了一系列切中时弊且影响深远的政治主张,但他却不被汉文帝所重用,究其原因,乃是因为贾谊的主张损害了朝廷重臣等人的既得利益,而汉文帝以藩王身份继承皇位,皇权有限,在强大的政治压力下将他贬为长沙王太傅。之后贾谊被迁升为梁怀王太傅,因其削藩措施不符合汉文帝以诸侯王国拱卫西汉中央王朝的思路,故也不被汉文帝采用。  相似文献   
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Manifestations of Fanconi Anemia Complementation Group C (FA-C) include multiple major congenital malformations, hypoplastic radius, absent thumb, growth retardation, elfin-like facial features, microphthalmia, microcephaly, café-au-lait spots, early onset of hematologic disease and poor survival (Auerbach, 1997). We describe two cases in which second-trimester sonographic findings led to parental carrier testing for FA-C and subsequent prenatal diagnosis of affected fetuses. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   
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Considerable attention has focused on inter- and intraspecific variation in trophic niches of marine predators. Although this has revealed evidence for sexual segregation in distribution in some species, few studies have been able to address sex-related dietary specialisation. Stable isotope analysis of blood cells collected from albatrosses and petrels at South Georgia during chick-rearing indicated a difference in δ13C, suggesting that females fed to the north of males, only in two species with male-biased sexual size dimorphism; in no species did sexes differ in trophic level (δ15N). Based on a wider review, significant differences between sexes in isotope signatures were much more common in seabirds during the pre-laying or breeding than the nonbreeding period, presumably reflecting greater between-sex partitioning of resources when foraging ranges are more constrained and competition is greater. Sex differences, or their absence, were usually consistent across successive stages during the pre-laying and breeding periods, but not necessarily year-round nor between populations. Significant differences in isotope signatures between males and females were extremely rare in monomorphic species, suggesting a link between sexual size dimorphism and segregation in diet or distribution. Among the Southern Ocean albatrosses, sex differences in δ13C suggested the underlying mechanism was related to habitat specialisation, whereas in other size-dimorphic taxa (both male- and female-biased), sex differences were more common in δ15N than δ13C and therefore more consistent with size-mediated competitive exclusion or dietary specialisation.  相似文献   
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Emotional labor—the management of emotional displays as part of one's work role—has emerged as a growth area of study within organizational behavior and customer service research. In this article, we call attention to the human costs of “service with a smile” requirements with little benefits. We first review the evidence showing that requiring positive emotions from employees induces dissonance and depleted resources, which hinders task performance and threatens well‐being. We articulate how formalized emotion display requirements limit self‐determination by threatening the autonomy, competence, and belongingness needs of employees. Further, via an organizational justice lens, we argue that emotional labor is an unfair labor practice because employees in such circumstances are (1) undervalued by the organization (constituting distributive injustice); (2) disrespected by customers (constituting interactional injustice); and (3) self‐undermined by organizational policies (constituting procedural injustice). We then argue for bringing light to the dark side of emotional labor with a “modest proposal”: Organizations and customers should abandon formalized emotion display expectations and replace such efforts with more humanistic practices that support and value employees, engendering positive climates and an authentically positive workforce. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
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Perchlorate (ClO4-) contamination of ground water and surface water is a widespread problem, particularly in the western United States. This study examined the effect of biodegradation on perchlorate fate and transport in soils. Solute transport experiments were conducted on two surface soils. Pulses of solution containing perchlorate and Br- were applied to saturated soil columns at steady state water flow. Perchlorate behaved like a nonreactive tracer in Columbia loam (coarse-loamy, mixed, superactive, nonacid, thermic Oxyaquic Xerofluvent) but was degraded in Yolo loam (fine-silty, mixed, superactive, nonacid, thermic Mollic Xerofluvent). Batch experiments demonstrated that perchlorate removal from solution in Yolo loam was caused by biodegradation. Other batch experiments with Yolo loam surface and subsurface soils, Columbia loam surface soil, and dredge tailings demonstrated that perchlorate biodegradation required anaerobic conditions, an adequate carbon source, and an active perchlorate-degrading microbial population. The sequential reduction of perchlorate and NO3- by an indigenous soil microbial community in Yolo loam batch systems was also studied. Nitrate reduction occurred much sooner than perchlorate reduction in soils that had not been previously exposed to perchlorate, but NO3- and perchlorate were simultaneously reduced in soils previously exposed to perchlorate. The results of this study have implications for in situ remediation schemes and for agricultural soils that have been contaminated by perchlorate-tainted irrigation water.  相似文献   
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