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51.
马泽威  全鹏 《心理科学》2015,(2):379-382
考察抑郁在青少年核心自我评价与自杀意念间的中介作用。对502名高中生进行量表测评。通过偏差校正的Bootstrap法和有先验信息的MCMC法求出中介效应值的95%置信区间分别为[-.030,-.011]和[-.024,-.014],提示抑郁的中介效应显著。效应量k2、R2med分别为.124、.104,偏差校正的Bootstrap法抽样5000次后,构建的效应量的95%置信区间分别为[.070,.178]、[.063,.156],两种指标共同验证效应量为中等。研究结果说明抑郁在核心自我评价与自杀意念间起部分中介作用,效应量中等。  相似文献   
52.
Sexist attitudes do not exist in a limbo; they are embedded in larger belief systems associated with specific hierarchies of values. In particular, manifestations of benevolent sexism (Glick and Fiske 1996, 1997, 2001) can be perceived as a social boon, not a social ill, both because they are experienced as positive, and because they reward behaviors that maintain social stability. One of the strongest social institutions that create and justify specific hierarchies of values is religion. In this paper, we examine how the values inherent in religious beliefs (perhaps inadvertently) propagate an unequal status quo between men and women through endorsement of ideologies linked to benevolent sexism. In a survey with a convenience sample of train passengers in Southern and Eastern Poland (N?=?180), we investigated the relationship between Catholic religiosity and sexist attitudes. In line with previous findings (Gaunt 2012; Glick et al. 2002a; Ta?demir and Sakall?-U?urlu 2010), results suggest that religiosity can be linked to endorsement of benevolent sexism. This relationship was mediated in our study by the values of conservatism and openness to change (Schwartz 1992): religious individuals appear to value the societal status quo, tradition, and conformity, which leads them to perceive women through the lens of traditional social roles. Adhering to the teachings of a religion that promotes family values in general seems to have as its byproduct an espousal of prejudicial attitudes toward specific members of the family.  相似文献   
53.
By atomic-scale high-angle annular dark-field scanning transmission electron microscopy, the long-period stacking ordered (LPSO) structures in a near-equilibrium Mg97Zn1Y2 (at.%) alloy have been characterised. In addition to 18R and 14H, new polytypes of LPSO structures are analysed and determined as 60R, 78R, 26H, 96R, 38H, 40H, 108H and 246R. All of these LPSO structures feature AB′C′A building blocks with two Mg layers and three Mg layers sandwiched between them. The Bravais lattices and space groups of new polytypes of LPSO structures were easily determined via the newly introduced method. A structural relationship between the LPSOs is proposed.  相似文献   
54.
有关数量化维度特征搜索的研究表明 ,目标搜索斜率 (反应时间对呈现项目数量函数的斜率 )是由目标与干扰子之间的差异决定的 ,然而以往研究中其差异的值取决于具体的实验条件。根据韦伯定律 ,笔者推测 ,目标搜索斜率应由目标与干扰子之间的相对差异 (C)决定 ,C为目标值 (T)与干扰子值 (D)的差值与该干扰子值的比值。当C值对应相等时 ,不同几何形状刺激的目标搜索斜率应无差异。为此笔者分别采用圆 (实验一 )和三角形 (实验二 )进行实验研究。实验结果支持了上述假设 ,并发现目标大于干扰子时的目标搜索斜率对C值的函数是单调递减函数  相似文献   
55.
A contraction-free and cut-free sequent calculus \(\mathsf {G3SDM}\) for semi-De Morgan algebras, and a structural-rule-free and single-succedent sequent calculus \(\mathsf {G3DM}\) for De Morgan algebras are developed. The cut rule is admissible in both sequent calculi. Both calculi enjoy the decidability and Craig interpolation. The sequent calculi are applied to prove some embedding theorems: \(\mathsf {G3DM}\) is embedded into \(\mathsf {G3SDM}\) via Gödel–Gentzen translation. \(\mathsf {G3DM}\) is embedded into a sequent calculus for classical propositional logic. \(\mathsf {G3SDM}\) is embedded into the sequent calculus \(\mathsf {G3ip}\) for intuitionistic propositional logic.  相似文献   
56.
Tripping and falling is a serious health problem for older citizens due to the high medical costs incurred and the high mortality rates precipitated mostly by hip fractures that do not heal well. Current falls prevention technology encompasses a broad range of interventions; both passive (e.g., safer environments, hip protectors) and active (e.g., sensor-based fall detectors) which attempt to reduce the effects of tripping and falling. However the majority of these interventions minimizes the impact of falls and do not directly reduce the risk of falling. This paper investigates the prediction of gait parameters related to foot-to-ground clearance height during the leg swing phase which have been physically associated with tripping and falling risk in the elderly. The objective is to predict parameters of foot trajectory several walking cycles in advance so that anticipated low foot clearance could be addressed early with more volitional countermeasures, e.g., slowing down or stopping. In this primer study, foot kinematics was recorded with a highly accurate motion capture system for 10 healthy adults (25-32 years) and 11 older adults (65-82 years) with a history of falls who each performed treadmill walking for at least 10 min. Vertical foot displacement during the swing phase has three characteristic inflection points and we used these peak values and their normalized time as the target prediction values. These target variables were paired with features extracted from the corresponding foot acceleration signal (obtained through double differentiation). A generalized regression neural network (GRNN) was used to independently predict the gait variables over a prediction horizon (number of gait cycles ahead) of 1-10 gait cycles. It was found that the GRNN attained 0.32-1.10 cm prediction errors in the peak variables and 2-8% errors in the prediction of normalized peak times, with slightly better accuracies in the healthy group compared to elderly fallers. Prediction accuracy decreased linearly (best fit) at a slow rate with increasing prediction horizon ranging from 0.03 to 0.11 cm per step for peak displacement variables and 0.34 × 10(-3) - 1.81 × 10(-3)% per step for normalized peak time variables. Further time series analysis of the target gait variable revealed high autocorrelations in the faller group indicating the presence of cyclic patterns in elderly walking strategies compared to almost random walking patterns in the healthy group. The results are promising because the technique can be extended to portable sensor-based devices which measure foot accelerations to predict the onset of risky foot clearance, thus leading to a more effective falls prevention technology.  相似文献   
57.
In this study, we investigated gender differences in problem solving as a function of problem context and expectations for success. Subjects were 90 women and 56 men from introductory psychology classes who were administered a set of mathematical problems varying in gender context under male-expectancy, female-expectancy, and neutral-expectancy conditions. No significant gender differences or interaction of gender with problem context were found. However, significant effects of problem context and expectancy were found. Both male and female subjects made higher scores on female-context problems and lower scores in the female-expectancy condition. When mathematics aptitude was used as a covariate, an interaction of gender with expectancy was found. Men in the female-expectancy condition made significantly lower scores than either men or women in the male-expectancy condition.  相似文献   
58.
59.
Tyrone Lai 《Synthese》1989,79(3):361-392
In trying to make discoveries, we are trying to uncover knowledge of HIDDEN realities. It appears impossible to uncover knowledge of hidden realities. How can we evaluate results? (How can we find out whether they are true or even good approximation when we cannot compare them to the hidden realities?) But we are often able to do things which appear impossible; it depends on whether we have chanced onto, or discovered, or invented, the relevant OPERATING PRINCIPLES. It appeared impossible to fly to the moon in one lifetime. We discovered the principle of the rocket. If we can discover the operating principle for making discoveries, we know how we make discoveries. In this paper, I show step by step how we can discover this operating principle.  相似文献   
60.
本文详细介绍了一例因为英语四级考试没有通过引发的一般心理问题的咨询过程。来访者韩某,女,20岁,是一名大二学生,因为英语四级考试没有通过而出现了睡眠质量差,学习效率下降,情绪低落等症状,来访者主动求助于校心理健康中心,迫切希望改变现状,能够正常的学习生活。咨询师在和来访者商议后根据其个性特征和问题的特点采用了合理情绪疗法对其进行干预,帮助她改变了其非理性的信念,经过咨询,来访者情绪好转,可以正确看待困难,取得了比较好的咨询效果。  相似文献   
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