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1.
Lussier Isabelle; Derevensky Jeffrey L.; Gupta Rina; Bergevin Tanya; Ellenbogen Stephen 《Canadian Metallurgical Quarterly》2007,21(2):165
The study of resilient children has overturned many deficit-focused models concerning the ontogenesis of children raised in adversity. This study explored the relationship between risk and protective factors, resilience, and youth gambling behavior. More specifically, this study examined the relative contribution of various risk and protective domains in relation to problem gambling behavior and examined whether youth identified as resilient (high risk exposure- high internalized protection) were as likely as those identified as vulnerable (high risk exposure-low internalized protection) to engage in excessive gambling behavior. The sample consisted of 1,273 students ages 12 to 19. The findings demonstrated that risk and protective factors each provide a unique contribution to the prediction model of gambling problems. Resilient and vulnerable youth differed significantly in their self-reported gambling severity. As well, resilient youth were not statistically distinguishable from low-risk exposure groups in terms of their gambling severity. Findings are interpreted with respect to resilience and prevention research. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
2.
A method for direct purine N isolation and determination was modified from the method of Zinn and Owens for rapid determination of purines. By this method, N derived from purines in digesta was measured and collected for 15N determinations. Measurements of purine N in 33 samples of ruminal contents and duodenal digesta of sheep and goats were compared with purine determinations in the same samples. The results showed that essentially all the N in the purines that could be isolated by the Zinn and Owens procedure also could be detected by N isolation and determination. Determinations of 15N in the NH3 N, NAN, and purine N fractions in a continuous culture in vitro showed significant differences in the 15N enrichment curves between diets based on either roasted or raw soybean meal. 相似文献
3.
Although the basal ganglia have been shown to be critical for the expression of emotion in prosody and facial expressions, it is unclear whether they are also critical for recognition of emotions. Selective pathology of parts of the basal ganglia is a hallmark of individuals with Parkinson's disease, and such patients have been examined in several studies of emotion. We examined 18 patients with Parkinson's disease (11 men, 7 women) and 13 age-, education-, gender ratio-, and IQ-matched normal controls on their ability to recognize emotions signaled by facial expressions. Parkinson's patients performed entirely normally on a quantitative task of recognizing emotional facial expressions. The findings do not support the notion that the sectors of basal ganglia that are dysfunctional in Parkinson's disease are essential for recognizing emotion in facial expressions. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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AND/OR search spaces accommodate advanced algorithmic schemes for graphical models which can exploit the structure of the
model. We extend and evaluate the depth-first and best-first AND/OR search algorithms to solving 0-1 Integer Linear Programs (0-1 ILP) within this framework. We also include a class
of dynamic variable ordering heuristics while exploring an AND/OR search tree for 0-1 ILPs. We demonstrate the effectiveness
of these search algorithms on a variety of benchmarks, including real-world combinatorial auctions, random uncapacitated warehouse
location problems and MAX-SAT instances. 相似文献
6.
Monuko du Plessis Herzl Aharoni Lukas W. Snyman 《Sensors and actuators. A, Physical》2000,80(3):242-248
A novel multi-terminal silicon light emitting device (TRANSLED) is described where both the light intensity and spatial light pattern of the device are controlled by an insulated MOS gate voltage. This presents a major advantage over two terminals Si-LEDs, which require direct modulation of the relatively high avalanche current. It is found that, depending on the bias conditions, the light intensity is either a linear or a quadratic function of the applied gate voltage. The nonlinear relationship facilitates new applications such as the mixing of electrical input signals and modulating the optical output signal, which cannot readily be achieved with two terminal Si-LEDs, since they exhibit a linear relationship between diode avalanche current and light intensity. Furthermore, the control gate voltage can also modulate the emission pattern of the light emitting regions, for example, changing the TRANSLED from an optical line source to two point sources. 相似文献
7.
There are two main solving schemas for constraint satisfaction and optimization problems: i) search, whose basic step is branching over the values of a variables, and ii) dynamic programming, whose basic step is variable elimination. Variable elimination is time and space exponential in a graph parameter called induced width, which renders the approach infeasible for many problem classes. However, by restricting variable elimination so that only low arity constraints are processed and recorded, it can be effectively combined with search, because the elimination of variables may reduce drastically the search tree size.In this paper we introduce BE-BB(k), a hybrid general algorithm that combines search and variable elimination. The parameter k controls the tradeoff between the two strategies. The algorithm is space exponential in k. Regarding time, we show that its complexity is bounded by k and a structural parameter from the constraint graph. We provide experimental evidence that the hybrid algorithm can outperform state-of-the-art algorithms in constraint satisfaction, Max-CSP and Weighted CSP. Especially in optimization tasks, the advantage of our approach over plain search can be overwhelming. 相似文献
8.
ieved in the study of gynecological cancers,early diagnosis,early treatment and valid recognition of precancerous stage are still the priority of therapy.The standardization of treatment on gynecological cancers remains to be generalized and the surgeries are prone to be humanize and individuate.The technique of clinical treatment should be based on evidence-based medicine and cooperation of multi-ceneri和L.hilgardii无法加以区分,但是仍有助于将未知杆菌归入这一群。 相似文献
9.
目的:探究天冬多糖的结构特征、免疫调节活性和体外抗氧化活性,为后续天冬多糖研究提供依据。方法:采用水提醇沉法提取天冬粗多糖,Sevage法脱蛋白和分级醇沉法对脱蛋白后的多组分多糖进行分离,苯酚-浓硫酸法测定其糖含量;采用高效凝胶渗透色谱法测定其相对分子质量,高效离子色谱法测定其单糖组成;采用红外光谱法分析其结构;对于均一分子质量的80%醇沉多糖分级产物(以下简称TD-80),采用小鼠脾淋巴细胞和巨噬细胞RAW264.7评价TD-80的免疫调节活性及其相关细胞因子的分泌情况。通过测定DPPH自由基清除能力、超氧阴离子清除能力评价其体外抗氧化活性。结果:天冬粗多糖糖含量为63.13%,天冬脱蛋白冻干粉糖含量达73.98%。不同体积分数乙醇分级醇沉后,80%醇沉产物为均一分子质量的多糖产物TD-80(Mw = 7.3 ku,Mw/Mn = 2.68)。TD-80主要含有7种单糖组成,其中以半乳糖和半乳糖醛酸为主,属于酸性杂多糖。TD-80能促进脾淋巴细胞的增殖,并呈质量浓度依赖关系,对相关细胞因子(TNF-α,IL-1β和IL-6)的分泌有一定的刺激作用,呈现一定的免疫调节活性和抗氧化活性。结论:本方法具有操作简便、结果准确等优点,可为天冬及其它类似药材中多糖的提取、纯化及药理活性研究提供参考。 相似文献
10.