首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
The signifiers, 'race', 'culture' or 'ethnicity' are utilized in the teenage pregnancy literature (1) to highlight 'differences' in adolescent sexual and reproductive behaviour and (2) as explanatory tools. When 'white' teenagers are the focus of research, psychological explanations are usually invoked, whereas for 'black' teenagers, explanations are socio-cultural in nature. In this article, we explore how, through a process of racialization, the psychomedical literature on teenage pregnancy in South Africa contributes to the entrenchment of 'race', 'culture' and 'ethnicity' as fixed, 'natural' signifiers. We utilize Derrida's notion of différance , together with Phoenix and Woollett's adaptation - 'normalized absence/pathologized presence' - to indicate how 'black' people are cast as the Other, the pathologized presence which relies on the normalized absent trace, 'whiteness', for definition. We analyse how the notions of 'tradition' and 'culture' are deployed to sanitize or disguise the underlying racializing project. 'Black' is exoticized and rendered strange and thus open to scrutiny, monitoring and intervention. 'Culture' and 'tradition' appeal to the myth of origin, thus providing pseudohistorical explanations which essentialize and naturalize racialized collectivities.  相似文献   

2.
Men generally prefer feminine women''s faces and voices over masculine women''s faces and voices, and these cross-modal preferences are positively correlated. Men''s preferences for female facial and vocal femininity have typically been investigated independently by presenting soundless still images separately from audio-only vocal recordings. For the first time ever, we presented men with short video clips in which dynamic faces and voices were simultaneously manipulated in femininity/masculinity. Men preferred feminine men''s faces over masculine men''s faces, and preferred masculine men''s voices over feminine men''s voices. We found that men preferred feminine women''s faces and voices over masculine women''s faces and voices. Men''s attractiveness ratings of both feminine and masculine faces were increased by the addition of vocal femininity. Also, men''s attractiveness ratings of feminine and masculine voices were increased by the addition of facial femininity present in the video. Men''s preferences for vocal and facial femininity were significantly and positively correlated when stimuli were female, but not when they were male. Our findings complement other evidence for cross-modal femininity preferences among male raters, and show that preferences observed in studies using still images and/or independently presented vocal stimuli are also observed when dynamic faces and voices are displayed simultaneously in video format.  相似文献   

3.
Although many studies have reported that women's preferences for masculine physical characteristics in men change systematically during the menstrual cycle, the hormonal mechanisms underpinning these changes are currently poorly understood. Previous studies investigating the relationships between measured hormone levels and women's masculinity preferences tested only judgments of men's facial attractiveness. Results of these studies suggested that preferences for masculine characteristics in men's faces were related to either women's estradiol or testosterone levels. To investigate the hormonal correlates of within-woman variation in masculinity preferences further, here we measured 62 women's salivary estradiol, progesterone, and testosterone levels and their preferences for masculine characteristics in men's voices in five weekly test sessions. Multilevel modeling of these data showed that changes in salivary estradiol were the best predictor of changes in women's preferences for vocal masculinity. These results complement other recent research implicating estradiol in women's mate preferences, attention to courtship signals, sexual motivation, and sexual strategies, and are the first to link women's voice preferences directly to measured hormone levels.  相似文献   

4.
How do people respond to others'' accidental behaviors? Reward and punishment for an accident might depend on the actor''s intentions, or instead on the unintended outcomes she brings about. Yet, existing paradigms in experimental economics do not include the possibility of accidental monetary allocations. We explore the balance of outcomes and intentions in a two-player economic game where monetary allocations are made with a “trembling hand”: that is, intentions and outcomes are sometimes mismatched. Player 1 allocates $10 between herself and Player 2 by rolling one of three dice. One die has a high probability of a selfish outcome, another has a high probability of a fair outcome, and the third has a high probability of a generous outcome. Based on Player 1''s choice of die, Player 2 can infer her intentions. However, any of the three die can yield any of the three possible outcomes. Player 2 is given the opportunity to respond to Player 1''s allocation by adding to or subtracting from Player 1''s payoff. We find that Player 2''s responses are influenced substantially by the accidental outcome of Player 1''s roll of the die. Comparison to control conditions suggests that in contexts where the allocation is at least partially under the control of Player 1, Player 2 will punish Player 1 accountable for unintentional negative outcomes. In addition, Player 2''s responses are influenced by Player 1''s intention. However, Player 2 tends to modulate his responses substantially more for selfish intentions than for generous intentions. This novel economic game provides new insight into the psychological mechanisms underlying social preferences for fairness and retribution.  相似文献   

5.
David D. Perkins 《Genetics》1974,77(3):459-489
Rapid, effective techniques have been developed for detecting and characterizing chromosome aberrations in Neurospora by visual inspection of ascospores and asci. Rearrangements that are detectable by the presence of deficient, nonblack ascospores in test crosses make up 5 to 10% of survivors after UV doses giving 10-55% survival. Over 135 rearrangements have been diagnosed by classifying unordered asci according to numbers of defective spores. (These include 15 originally identified or analyzed by other workers.) About 100 reciprocal translocations (RT''s) have been confirmed and mapped genetically, involving all combinations of the seven chromosomes. Thirty-three other rearrangements generate viable nontandem duplications in meiosis. These consist of insertional translocations (IT''s) (15 confirmed), and of rearrangements that involve a chromosome tip (10 translocations and 3 pericentric inversions). No inversion has been found that does not include the centromere. A reciprocal translocation was found within one population in nature. When pairs of RT''s that involve the same two chromosome arms were intercrossed, viable duplications were produced if the breakpoints overlapped in such a way that pairing resembled that of insertional translocations (27 combinations).—The rapid analytical technique depends on the following. Deficiency ascospores are usually nonblack (W: "white") and inviable, while nondeficient ascospores, even those that include duplications, are black (B) and viable. Thus RT''s typically produce 50% black spores, and IT''s 75% black. Asci are shot spontaneously from ripe perithecia, and can be collected in large numbers as groups of eight ascospores representing unordered tetrads, which fall into five classes: 8B:0W; 6B:2W, 4B:4W, 2B:6B, 0B:8W. In isosequential crosses, 90-95% of tetrads are 8:0. When a rearrangement is heterozygous, the frequencies of tetrad classes are diagnostic of the type of rearrangement, and provide information also on the positions of break points. With RT''s, 8:0 (alternate centromere segregation) = 0:8 (adjacent-1), 4:4''s require interstitial crossing over in a centromere-break point interval, and no 6:2''s or 2:6''s are expected. With IT''s, duplications are viable, 8:0 = 4:4, 6:2''s are from interstitial crossing over, 0:8''s or 2:6''s are rare. Tetrads from RT''s that involve a chromosome tip resemble those from IT''s, as do tetrads from intercrosses between partially overlapping RT''s that involve identical chromosome arms.—Because viable duplications and other aneuploid derivatives regularly occur among the offspring of rearrangements such as insertional translocations, care must be taken in selecting stocks, and original strains should be kept for reference.  相似文献   

6.
Four biotypes (pathotypes) of the citrus nematode, Tylenchulus semipenetrans, occurring in California, U.S.A. were differentiated on the basis of differences of infectivity on ''Homosassa'' sweet orange, ''Troyer'' citrange, ''Pomeroy'' and ''Rubidoux'' Poncirus trifoliata, ''Thompson Seedless'' grape, and ''Manzanillo'' olive. A method for differentiating biotypes of T. semipenetrans is described. Field observations indicate that biotypes of this nematode are very stable. The importance of using highly infective biotypes in the development and selection of satisfactory citrus-nematode-resistant rootstocks is emphasized.  相似文献   

7.
帕金森病是常见的神经退行性疾病,其发病原因至今尚未明确,目前的治疗方法价格昂贵、效果差且副作用大。帕金森病患者常见胃肠道功能障碍,帕金森病和肠道菌群之间的关联已得到实验证实,患者有望通过益生菌改善肠道菌群达到治疗的目的。工程益生菌的出现使得人们可以按照自己的意愿改造益生菌,提高其稳定性和靶向性,展现出其特有的应用潜力。本文将从益生菌治疗帕金森病的研究现状出发,阐述益生菌治疗帕金森病的可能机制,进一步分析工程益生菌治疗帕金森病的可行性,为该疾病的安全治疗提供新的思路。  相似文献   

8.
Eye contact and pointing are typical gestures in order to direct another individual''s attention toward a target. We previously investigated on Japanese monkeys whether joint attention ability encouraged by eye contact and pointing was associated with the imitation of human''s actions. The monkeys with the joint attention skills showed the imitation of human''s actions. In the current study, we investigated on a monkey whether joint attention ability also facilitated the imitation of human body-movements. Results showed that the monkey being taught eye contact and pointing showed the imitation of human body-movements. These results suggest that the monkeys have basic potential for following another individual''s motion, and that what imitation expresses depends on where the monkeys are paying attention. Thus, eye contact and pointing are suitable for directing the monkey''s attention toward the human.  相似文献   

9.
Impairment of endothelial function forms basis for many cardiovascular diseases, therefore today it becomes an independent target for therapeutic action, and the search for new compounds possessing endothelium-protective properties is one of the prospective goals of the pharmacotherapy and medicinal chemistry. An efficient instrument to solve the problem is the use of methods of molecular modeling. Application of the methods is possible only if detailed information on three-dimensional structure and function of molecular targets—receptors and enzymes responsible for signal transduction both inside and outside endothelial cells—is available. In the review we collected the data on the structure and functions of various macromolecules involved in the process of regulation of vascular tone. The structure of endothelial NO-synthase (EC 1.14.13.39) (eNOS) responsible for synthesis of nitrogen oxide and involved in the process of vascular tone regulation is described. The importance of its substrate, L-arginine, from the point of view of eNOS activity regulation is emphasized; the data on structure and functions of L-arginine transport system are presented. Also, various pathways of eNOS activity regulation are described, including activation and competitive inhibition through binding of exogenous substances in its active center and inhibition through caveolin binding at eNOS oxygenase domain among them, as well as regulation by means of phosphorylation of individual eNOS amino acid residues by protein kinases and their dephosphorylation by phosphatases. The importance of membrane receptors of endotheliocytes as targets for substances possessing endothelium-protective activity is emphasized. Receptors of endothelin, thrombocyte activation factor, prostaglandins, bradykinin, histamine, serotonin, and protein kinase-activated receptors are among them. The importance of calcium and potassium ion channels in vessel cells for endothelium protection is emphasized. Finally, the macromolecules discussed in the review are considered as targets in the search for endothelium-protective therapeutic agents by the proposed approaches and methods of molecular modeling.  相似文献   

10.
11.
12.
Abstract

Some demographers have argued that post‐World War II mortality declines in the less‐developed countries (LDC's) are not associated with economic and social development because of the diffusion of health and medical techniques from the developed to the underdeveloped countries. This paper examines the current relationship between socioeconomic development and mortality levels in 124 countries, 94 of which are LDC's. The argument is tested with a path model consisting of five multidimensional and three unidimensional indicators. Results indicate that for the LDC's, there is a very strong set of direct and indirect relationships between indicators of socioeconomic development and mortality. Between 62 and 80 per cent of the variances in the crude death rate, infant mortality, and life expectancy are explained in the LDC model. The empirical test of the model demonstrates that lower mortality levels in the LDC's are dependent on socioeconomic factors and health services; continued improvement of socioeconomic levels in the LDC's will result in further mortality declines. For comparative purposes, the same model also is tested for more developed countries. Results for the model with more developed countries (MDC's) show that entirely different measures are necessary for MDC mortality models; the concept of “mortality” for LDC's and MDC's is orthogonal and requires different empirical indicators.  相似文献   

13.
Following Hermann von Helmholtz, who described visual perceptions as unconscious inferences from sensory data and knowledge derived from the past, perceptions are regarded as similar to predictive hypotheses of science, but are psychologically projected into external space and accepted as our most immediate reality. There are increasing discrepancies between perceptions and conceptions with science''s advances, which makes it hard to define ''illusion''. Visual illusions can provide evidence of object knowledge and working rules for vision, but only when the phenomena are explained and classified. A tentative classification is presented, in terms of appearances and kinds of causes. The large contribution of knowledge from the past for vision raises the issue: how do we recognize the present, without confusion from the past. This danger is generally avoided as the present is signalled by real-time sensory inputs-perhaps flagged by qualia of consciousness.  相似文献   

14.
In a survey of the farming population of Orkney, Ayrshire, and East Lothian the prevalence of farmer''s lung was estimated at 86 per 1,000 in both Orkney and Ayrshire and 23 per 1,000 in East Lothian. If cases with a negative farmer''s lung hay (F.L.H.) precipitin test are excluded these figures are reduced to 43, 36, and nil respectively, but those for Orkney and Ayrshire are still about 20 times higher than any figure previously reported for the prevalence of farmer''s lung in Britain.Regional variations in prevalence are probably related both to climatic conditions and to differences in agricultural methods, the latter often being dictated by economic circumstances. Nevertheless the prevalence of farmer''s lung could be reduced considerably by the energetic application of preventive measures, backed by financial incentives. The most important of these are efficient drying of hay and cereals before storage, more extensive use of silage, better ventilation of farm buildings, and the introduction of mechanical feeding systems. Individual farmworkers could be taught how to recognize the early symptoms of the disease and encouraged to wear respirators when handling mouldy fodder.  相似文献   

15.
肿瘤目前成为人类健康和生命的重要危胁,肿瘤基因诊断是对肿瘤的各种原癌基因、抑癌基因进行检测,聚合酶链反应(polymerase chain reaction,PCR)技术是目前临床基因诊断应用最广泛的诊断技术,具有普及率高、特异性好、简便快捷等特点。肿瘤基因PCR诊断技术可以用于已知基因突变的检测,快速了解突变状态,有效制定治疗方案,为肿瘤患者带来福音。本研究主要基于专利数据,对肿瘤基因PCR诊断技术进行分析,探讨了全球与中国在肿瘤基因PCR诊断技术领域的发展现状与趋势。在Innography数据库共检索到PCR技术相关专利16,939件,专利家族6,285件。在肿瘤基因PCR诊断技术领域中,荧光定量PCR技术占比较大,约占肿瘤基因PCR诊断技术总量的三分之一。从技术技术生命周期来看,肿瘤基因PCR诊断技术目前仍处在高速发展阶段。美国是肿瘤基因PCR诊断技术的发展领先国家。该技术的主要来源国为美国,全球42.09%的专利来自美国,同时美国也是同族专利的主要分布地区。在肿瘤基因PCR诊断技术领域,排名前15位的顶尖机构中,来自美国的机构有7所。中国在肿瘤基因PCR诊断技术领域起步较晚,但发展迅速,在该技术领域申请的专利数量仅次于美国。中国申请的肿瘤基因PCR诊断技术的专利绝大多数都只在中国进行专利保护,并没有布局全球市场的意愿。  相似文献   

16.
Recent innovations have increased enormously the opportunities for investigating the molecular basis of bacterial pathogenicity, including the availability of whole-genome sequences, techniques for identifying key virulence genes, and the use of microarrays and proteomics. These methods should provide powerful tools for analysing the patterns of gene expression and function required for investigating host-microbe interactions in vivo. But, the challenge is exacting. Pathogenicity is a complex phenotype and the reductionist approach does not adequately address the eclectic and variable outcomes of host-microbe interactions, including evolutionary dynamics and ecological factors. There are difficulties in distinguishing bacterial ''virulence'' factors from the many determinants that are permissive for pathogenicity, for example those promoting general fitness. A further practical problem for some of the major bacterial pathogens is that there are no satisfactory animal models or experimental assays that adequately reflect the infection under investigation. In this review, we give a personal perspective on the challenge of characterizing how bacterial pathogens behave in vivo and discuss some of the methods that might be most relevant for understanding the molecular basis of the diseases for which they are responsible. Despite the powerful genomic, molecular, cellular and structural technologies available to us, we are still struggling to come to grips with the question of ''What is a pathogen?''  相似文献   

17.
18.
Review of a 1993 survey of the 29 United Kingdom departments of general practice (or equivalent) identified seven master''s degree courses available for general practitioners. Up to another 11 are planned within the next five years. Around 50 general practitioners undertake all such courses at any one time. Possible reasons for this low uptake include cost, lack of flexibility of courses, and the prospect of writing a thesis. Appropriate master''s courses are essential to the future development of general practice, and this paper postulates the characteristics of an "ideal" course.  相似文献   

19.
Abstract

Survivorship curves and life tables for the 1971-75 generations of currant clearwing in an unsprayed blackcurrant (cv. 'Cotswold Cross') plantation and for the 1972-74 generations in a sprayed blackcurrant plantation (cvs 'Cotswold Cross' and 'Magnus') are presented. The key element in the life cycle is identified as adult survival, and the density dependence of the various mortalities is identified by various indices. The possible effects on population levels of currant clearwing of the proposed pruning management for mechanically harvested blackcurrants is discussed.  相似文献   

20.
The Bahamian archipelago has a rich flora with 89 endemic species. An international symposium held at Nassau in October 2012 to celebrate the 30th anniversary of the publication of the “Flora of the Bahama Archipelago” provided a forum to discuss plant conservation issues on these islands. This article builds on conclusions from this symposium and results from joint plant conservation research projects among the authors. The two main conservation challenges for these islands are: (1) environmental uncertainties derived from global warming and associated sea level changes and (2) the need for increased plant conservation awareness among the predominant urban population of the archipelago. Legal tools and biodiversity international agreements in place for The Commonwealth of the Bahamas can facilitate mechanisms for effective plant conservation. Further legal developments need to be established in The United Kingdom Overseas Territory of The Turks and Caicos Islands. There is an urgent need to redevelop the Botanic Garden of Nassau and designate it as the national botanic garden of The Bahamas. Further research related to the taxonomy, biology, conservation status, and distribution of the endemic species is urgently needed. Research initiatives pertinent to the detrimental effect and biology of invasive species are also lacking. The heterogeneous environments and uneven distribution of human populations across the archipelago are major challenges for conservation. Finally because of the political and economic status of The Bahamas and The Turks and Caicos, conservation agencies from the archipelago do not have easy access to international or British/European Union funds for global conservation initiatives.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号