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151.
MOTHERS AND TEACHERS of 94 children (53 boys) with Down syndrome, between 8 and 14 years of age, rated the children on a temperament scale and provided an overall impression as to whether the child was difficult in comparison with other children. Maternal ratings on the Middle Childhood Questionnaire showed significant differences from standardization scores. Children with Down syndrome were given ratings as less active, more predictable, of more positive mood, less persistent, and more distractible. Some of these dimensions favour the amiable personality stereotype for the syndrome but low persistence was associated with maternal impressions of difficulty. There was little agreement between mothers and teachers regarding the individual children who were rated as being significantly easier or more difficult than other children. Results with a subgroup (n = 32) showed that externalizing behaviours were significantly related to both mother and teacher impressions of difficulty and that mothers also found intense, active, distractible behaviour difficult.  相似文献   
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  总被引:1,自引:0,他引:1  
A survey of Australian PhD graduates has revealed that they do not necessarily fit traditional stereotypes in terms of age, previous or concurrent work experience nor, perhaps most importantly, a prospective career in research. Two years after graduating with PhD, just 36 per cent of those who found employment in the non-academic workforce continued to be 'xtensively' involved in research, while only 56 per cent of those in academic employment (other than those with postdoctoral fellowships) were so involved. Many of those trained in research are frustrated in not being able to implement and extend that training through appropriate employment, others who have the opportunity do not have the desire. Factors predictive of and related to continuing involvement in research are examined, with some surprising results and policy implications regarding postgraduate research degrees.  相似文献   
155.

A total of 189 engineers, both students and qualified engineers of both sexes at two universities in Bulgaria, were given a questionnaire addressing the issue of why such a high proportion of engineers in Bulgaria were women compared with Britain. Answers were both fixed answer and open ended. The responses stressed the importance of the need for women to work for economic reasons and the role of the previous (communist) system in emphasizing the importance of both engineering and gender equity in its policies, including its educational policy. Qualified engineers were slightly more ready to stress these ‘system’ factors than student engineers. Engineering in Bulgaria had not been altered in any way which would take account of Western feminist criticism of engineering, but was perceived as being taught more theoretically and via lectures than in Britain. A contemporary strong switch away from engineering into economics and business was perceived. It is not clear yet whether gender neutral engineering will survive in Bulgaria.  相似文献   
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The paper describes an attempt to provide students with a choice of learning media with which to absorb basic library skills. We were interested in seeing whether students particularly favoured one medium rather than another, and also, from the point of view of our Media Services section, we were concerned with comparing the various formats with regard to their effectiveness in communicating this particular information  相似文献   
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微生物给人类带来了有利又有害的一面。这些有利的影响一般源于人们与微生物之间的共生关系。但是人类一些疾病的产生使得看似友好的微生物成为条件致病菌,使人们感染上微生物相关的疾病。人们致力于研究多种抗菌剂用于治疗和抑制病原微生物的感染,但是微生物耐药性的出现使得人们的研究进程受阻。尽管已有大量关于药物开发的研究缓解了这个难题,但微生物对这些药物的耐受性以及持续的微生物进化变异,使研究人员把重点放在筛选各种植物膳食类化合物上以用于抗菌。亚麻酸及其衍生物(二十碳五烯酸和二十二碳六烯酸)是已被广泛研究的omega-3脂肪酸,在人类的健康方面扮演着重要的角色,对大脑、眼睛、心血管系统和人的正常成长都有重要作用。然而,作为抗菌剂的使用并没有受到人们广泛的重视,可能是由于人们缺乏对其抗菌机制、药理毒性以及给药方式的了解。因此,本文综述了omega-3脂肪酸作为替代药物在治疗和预防微生物相关疾病中的作用。  相似文献   
160.
The mechanical behavior of cells offers insight into many aspects of their properties. We propose an approach to the mechanical analysis of cells that uses a combination of electromanipulation for stimulus and capacitance for sensing. To demonstrate this approach, polystyrene spheres and yeast cells flowing in a 25 μm×100 μm microfluidic channel were detected by a perpendicular pair of gold thin film electrodes in the channel, spaced 25 μm apart. The presence of cells was detected by capacitance changes between the gold electrodes. The capacitance sensor was a resonant coaxial radio frequency cavity (2.3 GHz) coupled to the electrodes. The presence of yeast cells (Saccharomyces cerevisiae) and polystyrene spheres resulted in capacitance changes of approximately 10 and 100 attoFarad (aF), respectively, with an achieved capacitance resolution of less than 2 aF in a 30 Hz bandwidth. The resolution is better than previously reported in the literature, and the capacitance changes are in agreement with values estimated by finite element simulations. Yeast cells were trapped using dielectrophoretic forces by applying a 3 V signal at 1 MHz between the electrodes. After trapping, the cells were displaced using amplitude and frequency modulated voltages to produce modulated dielectrophoretic forces. Repetitive displacement and relaxation of these cells was observed using both capacitance and video microscopy.  相似文献   
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