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91.
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Children exposed to alcohol prenatally may suffer from severe brain damage, expressed as a variety of behavioral problems, including hyperactivity and learning deficits. There is a critical need to identify effective treatments for fetal alcohol effects. Physical exercise enhances cognitive ability and increases neurogenesis in the hippocampus, a brain area important for learning and memory. Thus, the present study examined whether physical exercise might reduce the severity of alcohol-induced behavioral alterations. Sprague-Dawley rats were intubated with 5.25 g/kg/day ethanol during the third trimester equivalent (postnatal days [PDs] 4-9). Intubated sham control and nontreated controls were included. From PD 21 to PD 51, half of the subjects were given access to running wheels. On PD 52, subjects were tested on the Morris water maze, and on PD 60, open field activity levels were measured. Morris maze performance was significantly impaired among ethanol-exposed subjects; exercise significantly improved performance of all groups. Similarly, ethanol-exposed subjects were overactive in the open field, an effect attenuated with exercise. In sum, these data suggest that exercise may increase neuronal plasticity not only in controls, but also in subjects exposed to alcohol during development. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
93.
The purpose of the present study was to examine the effectiveness and feasibility of phonological awareness training, with and without a beginning decoding component. 33 teachers in 8 urban schools were assigned randomly within their schools to 3 groups: control, phonological awareness training, and phonological awareness training with beginning decoding instruction and practice. Following training, teachers in the 2 treatment groups conducted the treatments for about 20 wks. In each teacher's class, pre- and posttreatment data were collected on 12–14 children (N?=?404); 312 children were tested again the following fall. At the end of kindergarten, the 2 treatment groups performed comparably and outperformed controls on the phonological awareness measures. On alphabetic (reading and spelling) tasks, however, the group participating in phonological awareness training with beginning decoding instruction did better than the other 2 groups. In the fall of the next year, many of these between-group differences remained but were less impressive. Implications are discussed for bridging research and practice. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
94.
A thorough understanding of consumer confidence in the safety of food and the factors by which this is influenced is necessary for the development of adequate and effective risk management and communication regarding food safety issues. As food chains become globalized, risk management and communication are increasingly applied at international levels. As a consequence, cross-culturally valid theoretical models are needed to investigate consumer confidence in the safety of food. In this study, consumer confidence in the safety of food in Canada and the Netherlands was systematically compared. On the basis of two nationally representative samples, it was examined to what extent differences in consumer confidence between the two countries resulted from differences in the relative importance of the determinants of confidence, and differences in the means of the constructs. No differences between Canada and the Netherlands were found regarding the relative importance of the determinants, which provides support for the generalizability of the framework. However, results indicated that Dutch consumers had a higher level of optimism and a lower level of pessimism regarding the safety of food, which appeared to be mainly related to Dutch consumers’ lower level of concern about factors related to production. The results also indicated cross-national differences in consumer recall of food safety issues in the media.  相似文献   
95.

Background  

Parents who perceive common infant behaviors as formula intolerance-related often switch formulas without consulting a health professional. Up to one-half of formula-fed infants experience a formula change during the first six months of life.  相似文献   
96.
A previous randomized trial with 224 alcohol and/or cocaine addicts who had completed an initial phase of treatment indicated that 12 weeks of telephone-based continuing care yielded higher abstinence rates over 24 months than did group counseling continuing care. The current study examined mediators of this treatment effect. Results suggested that self-help involvement during treatment and self-efficacy and commitment to abstinence 3 months after treatment mediated subsequent abstinence outcomes. These analyses controlled for substance use prior to the assessment of mediators. Conversely, there was no evidence that self-help beliefs or social support mediated the treatment effect. These results are consistent with a model in which treatment effects are first accounted for by changes in behavior, followed by changes in self-efficacy and in commitment to abstinence. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
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正几个世纪以来,不同的地理环境一直都采用这类封闭的庭院形式——每一次都根据当地气候、风俗习惯和建筑实践进行改造。作为一种在建筑物内捕捉户外景观的手段,庭院由建筑内部结构决定。流畅的庭院不但提供内外部隐私保护,而且也不断地向外延伸,积极融入周边景观。该住宅遵守严格的分区指导方针,同时通过在屋顶上扩建自然植物区系与景观融合。坐落在橄榄树林、松树和葡萄园内,该住宅充分利用坡地,从而获得可持续的拓展和种植  相似文献   
99.
Fluorogenic enzyme probes go from a dark to a bright state following hydrolysis and can provide a sensitive, real‐time readout of enzyme activity. They are useful for examining enzymatic activity in bacteria, including the human pathogen Mycobacterium tuberculosis. Herein, we describe two fluorogenic esterase probes derived from the far‐red fluorophore 7‐hydroxy‐9H‐(1,3‐dichloro‐9,9‐dimethylacridin‐2‐one) (DDAO). These probes offer enhanced optical properties compared to existing esterase probes because the hydrolysis product, DDAO, excites above 600 nm while retaining a good quantum yield (?=0.40). We validated both probes with a panel of commercially available enzymes alongside known resorufin‐ and fluorescein‐derived esterase substrates. Furthermore, we used these probes to reveal esterase activity in protein gel‐resolved mycobacterial lysates. These probes represent new tools for esterase detection and characterization and should find use in a variety of applications.  相似文献   
100.
The catalytic dehydrogenation (DH) and oxidative dehydrogenation (ODH) of light alkanes are of significant industrial importance. In this work both carbonaceous material deposited on VOx/Al2O3 catalysts during reaction and unsupported carbon nanofibres (CNFs) are shown to be active for the dehydrogenation of butane in the absence of gas-phase oxygen. Their activity in these reactions is shown to be dependent upon their structure, with different reaction temperatures yielding structurally different coke deposits. Terahertz time-domain spectroscopy (THz-TDS), among other techniques, has been applied to the characterisation of these deposits – the first time this technique has been employed in coke studies. TEM and other techniques show that coke encapsulates the catalyst, preventing access to VOx sites, without a loss of activity. Studies on CNFs confirm that carbonaceous materials act as catalysts in this reaction. Carbon-based catalysts represent an important new class of potential catalysts for DH and ODH reactions.  相似文献   
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