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41.
There is an urgent need for new drugs for the treatment of tropical parasitic diseases such as human African trypanosomiasis, which is caused by Trypanosoma brucei. The enzyme trypanothione reductase (TryR) is a potential drug target within these organisms. Herein we report the screening of a 62 000 compound library against T. brucei TryR. Further work was undertaken to optimise potency and selectivity of two novel‐compound series arising from the enzymatic and whole parasite screens and mammalian cell counterscreens. Both of these series, containing either a quinoline or pyrimidinopyrazine scaffold, yielded low micromolar inhibitors of the enzyme and growth of the parasite. The challenges of inhibiting TryR with druglike molecules is discussed.  相似文献   
42.
The impact of waste disposal on marsh soils was assessed in topsoil samples collected at eight randomly selected points in the salt marsh in Ramallosa (Pontevedra, Spain) at 4-month intervals for 2 years. Polluted soil samples were characterized in physico-chemical terms and their heavy metal contents determined by comparison with control, unpolluted samples. The results revealed a marked effect of waste discharges on the soils in the area, which have low contents in heavy metals under normal environmental conditions. In fact, the studied soils were found to contain substantial amounts of total and DTPA-extractable Cd, Cu, Pb and Zn. Based on the relationship of the redox potential with the DTPA-extractable Cd, Cu, Pb, and Zn contents of the soils, strongly reductive conditions raised the total contents in these elements by effect of their remaining in the soils as precipitated sulphides. Such contents, however, decreased as oxidative conditions gradually prevailed. The contents in DTPA-extractable metals increased with increasing Eh through the release of the metals in ionic form to the soil solution under oxidative conditions. The contents in heavy metals concentrating in the polluted soils were several times higher than those in the control soils (viz. 2 vs. 6 for Cd, 4 vs. 6 for Cu, 4 vs. 20 for Pb, and 2 vs. 15 for Zn, all in mg kg−1). This can be expected to influence the amounts of available heavy metals present in the soils, and hence the environmental quality of the area, in the near future. Based on its geoaccumulation index (Class ≥3 for Cd and Cu, and 1–4 for Pb and Zn), the Ramallosa marsh is highly polluted with Cd and moderately to highly polluted with Cu, Pb and Zn. The enrichment factors obtained confirm that the salt marsh is highly polluted (especially with Cd) as the primary result of anthropic activity.  相似文献   
43.
In this study, the authors examined parent-adolescent cortisol associations in 45 families with adolescent children (24 girls; M age = 15.78 years, SD = 1.44 years). Family members’ salivary cortisol levels were measured seven times a day on 2 typical weekdays. Family members provided reports of demographic and health variables, and adolescents rated parent-child relationship characteristics. After accounting for the effects of time of day and relevant demographic and health control variables on cortisol levels, hierarchical linear models indicated the presence of significant covariation over time in mother-adolescent cortisol (i.e., physiological synchrony). Furthermore, moderating tests revealed that mother-adolescent cortisol synchrony was strengthened among dyads characterized by mothers and adolescents spending more time together, and in families rated higher on levels of parent-youth shared activities and parental monitoring or supervision. Analysis of momentary characteristics indicated that maternal presence at the time of cortisol sampling lowered adolescent cortisol levels but did not account for mother-adolescent cortisol synchrony. Within-family physiological synchrony was amplified in momentary contexts of elevated maternal negative affect and elevated adolescent negative affect. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Film music has powerful aesthetic effects on the perception and understanding of screen content, but does it also influence viewers' sense of connection with movie characters thereby creating antecedents for an experience of empathy? Participants viewed clips showing characters' neutral or ambiguous reaction to an event, person, or object. Viewers rated character likability and their certainty about characters' thoughts in three conditions: thriller music, melodrama music, and no music. The effect of music conditions differed significantly from the no music condition. Compared to melodramatic music, thriller music significantly lowered likability and certainty about characters' thoughts. During subsequent cued recall of screen content, thriller music increased anger attributions and lowered sadness attributions, while melodramatic music increased love attributions and lowered fear attributions. The study provides evidence that film music can influence character likability and the certainty of knowing the character's thoughts, which are antecedents of empathetic concern and emphatic accuracy. Thus film music may be regarded as modulating antecedents of empathic concern and empathic accuracy. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
46.
The ideas of children about the environmental impact of vehicle emissions have been explored using a precoded questionnaire. The children were from British National Curriculum Years 7 (age 11/12 years), 9 (age 13/14) and 11 (age 15/16). Even in the oldest group only about half of the children appreciated the advantages of smaller, well‐maintained cars; this could have practical implication if not corrected in the adult population. Children seemed well aware of the environmental problems, smog, Acid Rain and Global Warming, to which vehicle emissions contribute, but these are part of an over‐generalised model which children employ in which cars are envisaged as contributing to other problems such as Ozone Layer depletion. We suggest that the use of the generic term ‘pollution’ to describe a wide range of environmental insults and the use of the word ‘environment’ in a non‐defined way might hinder children's differentiation of the different causes of separate environmental problems. The gaps in children's knowledge of the different components of vehicle emissions may reflect and exacerbate this difficulty. Ironically, children have a regard for the environmental and an interest in cars, and a combination of these enthusiasms may provide an opportunity for environmental education and curriculum science teaching.  相似文献   
47.
Reports an error in "Does Barbie make girls want to be thin? The effect of experimental exposure to images of dolls on the body image of 5- to 8-year-old girls" by Helga Dittmar, Emma Halliwell and Suzanne Ive (Developmental Psychology, 2006 Mar, Vol 42[2], 283-292). A substantive error occurs in the Body shape dissatisfaction section on page 287. The sentence describing the calculation of body shape dissatisfaction scores from girls' responses to the Child Figure Rating Scale should instead read as follows: "A body shape dissatisfaction score was computed by subtracting the girl's actual from her ideal body size." (The following abstract of the original article appeared in record 2006-03514-007.) The ubiquitous Barbie doll was examined in the present study as a possible cause for young girls' body dissatisfaction. A total of 162 girls, from age 5 to age 8, were exposed to images of either Barbie dolls, Emme dolls (U.S. size 16), or no dolls (baseline control) and then completed assessments of body image. Girls exposed to Barbie reported lower body esteem and greater desire for a thinner body shape than girls in the other exposure conditions. However, this immediate negative impact of Barbie doll was no longer evident in the oldest girls. These findings imply that, even if dolls cease to function as aspirational role models for older girls, early exposure to dolls epitomizing an unrealistically thin body ideal may damage girls' body image, which would contribute to an increased risk of disordered eating and weight cycling. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
48.
In this paper, the diagnosability of n-dimensional star graph Sn under the comparison diagnosis model has been studied. It is proved that Sn is (n−1)-diagnosable under the comparison diagnosis model when n?4.  相似文献   
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50.
This article presents an elaborated model of organizational regression suggesting that, within the framework of general systems and catastrophe theory, organizational units and whole enterprises can be viewed as struggling to attain a state of super-resilience that enables them to cope effectively with a large number of regressive forces. The model comprises 6 phases of organizational regression that occur either in a 10-stage process or in a chaotically unpredictable but behaviorally understandable and orderly sequence. Internal and external regressive forces that constantly pressure an organization toward less effective performance and more primitive behavior are identified. Organizational barriers and balancing forces that counter the regressive pressures are also described, along with the consequences of regression for individuals and enterprises. Several brief case illustrations (e.g., Montgomery Ward, Apple Computer, and General Electric Corporation) are provided to highlight aspects of this conceptual approach. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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