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101.
The authors reviewed the evidential basis of three environmental approaches to reducing population obesity: What are the effects of (a) taxing or subsidizing foods, (b) manipulating the ease of food access, and (c) restricting access to certain foods? A narrative review evaluated evidence using National Heart, Lung, and Blood Institute criteria. There was strong evidence that subsidization influences food purchases, but not necessarily food consumption or body weight. Ease of food access may influence food purchases, and possibly food intake and body weight. Data on restriction were lacking. More studies are needed to justify that altering these macro-environmental variables will necessarily reduce population obesity. A proposed conceptual model posits that the steps through environmental interventions may exert intended and unintended influences on body weight and obesity prevalence. Contemplated policy changes should weigh scientific evidence with social judgments and values concerning changes to the environment. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
102.
The authors investigated relationships between marijuana and inhalant use and several cultural and demographic factors in Anglo American and Hispanic American adolescents (N=1,094). Outcome measures assessed lifetime and 30-day marijuana and inhalant use. Predictors and covariates used in logistic regression analyses were region, grade, gender, knowledge, acculturation, familism, and parental monitoring. Hispanic Americans exhibited higher usage across all measures. In this group, high acculturation was associated with low marijuana, but high inhalant, use. Across all participants, positive family relations and parental monitoring were strongly associated with attenuated marijuana use hut only among those most knowledgeable about drugs. Familism and monitoring were not associated with diminished usage among the less knowledgeable. For inhalants, monitoring combined with high knowledge or high familism was associated with diminished usage. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
103.
较详细地介绍了在北京核电厂模拟培训中心的模拟器上建立RMS仿真系统的工作。首先对仿真的原型进行分析和简化,建立数学物理模型,并对包括RCS、PZR、SG、CVCS等的近20个核电厂系统进行了动态仿真建模,确定RMS各监测点放射性水平仿真读数的计算方法,最后,给出部分仿真实验结果,以验证数学物理模型的可靠性和适用性。  相似文献   
104.
海洋是个特殊的环境,为许多光纤传感器提供了一个极好的应用领域。对于海洋这个特殊的“敌对”环境,光纤传感器将面临许多挑战。 本文着重介绍应用于海水温度、浊度、盐份浓度、浮游生物和溶解物光吸收量以及环境湿度等海洋环境参数监测的光纤传感器的原理、结构和特性,展望光纤传感器在海洋环境监测方面的美好前景。  相似文献   
105.
通过对西安绿色康居小区规划设计的实例分析,阐明了小康型住宅区的标准和要求,在旧城住宅区改造中的落实和运用,试图探索下一世纪旧城住宅区的改造之路.  相似文献   
106.
Reflectance anisotropy spectroscopy (RAS) has been used to study As-by-P exchange during metalorganic vapor phase epitaxy. The study focuses on the processes occurring during switching from GaAs to GaInP, especially the effect of purging PH3 over a GaAs surface. GaAsP/GaAs superlattices of different periodicity were grown and the P-content was determined by high-resolution x-ray diffraction and correlated to the RAS spectra. From the temperature dependence of the P-content, an activation energy of 0.56 eV was estimated for the incorporation mechanism. In addition to the insights into the processes at mixed group-V heterointerfaces, our study demonstrates the reproducibility of RAS transients that thus can be used for process monitoring.  相似文献   
107.
通过对几座典型水库大坝原型观测设施的分析论证,总结了土坝测压管观测设备分析论证的步骤和方法,从观测设施的考证及全面性、合理性、可靠性等方面进行分析,以确定各测压管的可操作性,从而为观测资料的准确性以及整编分析提供可靠的保证。  相似文献   
108.
Humanitarian psychological support as an organized field is relatively young. Pioneers in the field were involved primarily in providing psychological support to refugees and internally displaced persons in conflict and nonconflict situations. This article describes basic principles for the design of psychological support programs and interventions. The International Federation of Red Cross and Red Crescent Societies (IFRC) began a psychological support program in 1991. The IFRC chose psychological first aid as its model for implementation in developing countries. Psychological first aid fits all the principles for psychological support program design and is adapted to individual communities. The first generation of psychological support programs differed dramatically depending on the countries in which they were developed. A second generation of psychological support programs evolved in response to the earthquake/tsunami of December 26, 2004. The Inter-Agency Standing Committee international guidelines consolidated the advances of second-generation programs and provided a clear indication of the wide acceptance of the importance of psychological support. A glimpse is provided of the third generation of psychological support programs, and an admonition is made for a more empirical evaluation of the effectiveness of interventions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
109.
结合紫金苑工程实例,分析喷锚结合水泥搅拌桩在基坑支护中的应用并总结施工、监测经验。  相似文献   
110.
Determining contributions of source-monitoring and inhibitory function to age-related forgetting has been an elusive goal for cognitive theorists. Five studies used a verbal working memory paradigm to examine mechanisms accounting for disproportionate retroactive interference (RI) experienced with adult aging. Participants distinguished studied target-word pairs from interfering pairs that were read aloud. Source-monitoring and inhibitory task components varied through manipulations of response requirements. RI effects were primarily due to source-monitoring failures rather than to inhibitory failures. Removing both source and inhibitory components eliminated age differences in RI. When source monitoring was emphasized, RI continued to be observed in all age groups but disproportionately for older adults. Process dissociation analyses of memory found recollection decreases and familiarity increases consistent with source failures. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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