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211.
Gail A. Wasserman Pam Factor-Litvak Xinhua Liu Andrew C. Todd Jennie K. Kline Vesna Slavkovich 《Child neuropsychology》2013,19(1):22-34
We report associations between serial measures of blood lead and intelligence in children age 10–12 years, half heavily exposed to lead from the prenatal period onward, and half relatively unexposed. For a subsample, we examine bone lead-IQ associations, comparing them with blood lead associations. Both blood and bone lead levels were associated with intelligence decrements, small relative to the contribution of social factors. For each doubling of Tib-Pb, Full Scale, Performance, and Verbal IQ decreased by an estimated 5.5, 6.2, and 4.1 points, respectively. Bone lead-IQ associations were stronger than those for blood lead, which nonetheless provide robust analogues. Current BPb, easy to obtain, provides a useful means for assessing Pb exposure/IQ associations. 相似文献
212.
HaiYing Wu YaHong Chen XinFang Su ChengRong Deng Zi-Jiang Liu 《Philosophical Magazine Letters》2013,93(4):198-204
A phase transition of MgS under high pressure is investigated using a first-principles method. It is found from energy-volume calculations that the rock-salt (B1) phase of MgS transforms into a FeSi-type (B28) phase at 143?GPa. The calculated ground-state parameters in the B1 phase are in excellent agreement with available experimental and theoretical data. Ab initio phonon calculations are also performed to investigate the structural behaviour of MgS under high pressure. An unstable transverse acoustic mode and a phase transition from B1 to B28 phase at ~143.7?GPa driven by this soft mode are predicted. The B28 structure of MgS is stable up to 350?GPa according to lattice dynamics calculations. 相似文献
213.
In this study, (Gd1? x Nd x )2(Zr1? x Ce x )2O7 (0 ≤ x ≤ 0.5) ceramics have been prepared by pressureless sintering at 1973 K to investigate the influence of Nd and Ce co-doping on their electrical conductivity. The electrical conductivity of the ceramics was investigated by impedance spectroscopy measurements from 723 to 1173 K over the frequency range of 20 Hz to 2 MHz in air. The measured values obey the Arrhenius relation. For each composition, the grain conductivity gradually increases with increasing temperature from 723 to 1173 K. At a given temperature, it gradually decreases with increasing neodymium and cerium contents from x = 0 to 0.3; thereafter, the grain conductivity exhibits a slight increase with further increasing neodymium and cerium contents up to x = 0.5. 相似文献
214.
The effect of chemical stresses upon the relation between extended dislocations and high-temperature creep in a thin plate has been investigated. The critical stress needed for the contraction of extended jogs and its effect on the creep rate are obtained. The results indicate that the critical stress needed for the contraction increases with decreasing stacking fault energy (SFE). However, creep occurs more easily with increasing SFE and increasing angle of the Burgers vector to the dislocation line, as well as with the concentration of any diffusing atoms. 相似文献
215.
How likely is the glass to break, given that it is heated? The present study asks questions such as this with or without the premise if the glass is heated, it breaks. A reduced problem (question without premise) measures the statistical dependency (conditional probability) of an event to occur, given that another has occurred. Such statistical dependency represents knowledge-based reasoning (inferring from “glass heated” to “its breaking”) and is a component of the response to the complete problem (question with premise). The complete problems therefore measure not only knowledge-based reasoning in terms of statistical dependencies (inductive component) but assumption-based reasoning (deductive component). Two experiments revealed: a) Knowledge-based reasoning continues to develop and attains adult levels at 7th grade for the problems tested, and b) assumption-based reasoning (deductive component) is reliable only for secondary school students (7th graders). 相似文献
216.
Xufeng Liu Yang Liao Luping Zhou Gang Sun Min Li Lun Zhao 《Cognitive, affective & behavioral neuroscience》2013,13(3):491-500
The aim of the present study was to investigate the time course of the positive advantage in the expression classification of faces by recording event-related potentials (ERPs). Although neutral faces were classified more quickly than either happy or sad faces, a significant positive classification advantage (PCA)—that is, faster classification for happy than for sad faces—was found. For ERP data, as compared with sad faces, happy faces elicited a smaller N170 and a larger posterior N2 component. The P3 was modulated by facial expressions with higher amplitudes and shorter latencies for both happy and neutral stimuli than for sad stimuli, and the reaction times were significantly correlated with the amplitude and latency of the P3. Overall, these data showed robust PCA in expression classification, starting when the stimulus has been recognized as a face revealed by the N170 component. 相似文献
217.
Yanbo Wang Hongbiao Wang Ji Wang Jing Wu Xiaohong Liu 《Journal of clinical psychology in medical settings》2013,20(1):3-12
This study examined prevalence and predictors of posttraumatic growth in 180 accidentally injured patients of mainland China in their convalescence stage, investigating its relationships with demographic and accidental injury variables, personality, posttraumatic stress disorder (PTSD) symptoms, and coping styles. Our results showed that posttraumatic growth (PTG) presented mostly in the domain of Relating to Others and indicated that PTG was significantly related to marital status, educational level, personality, coping styles, and PTSD symptoms. Avoidance of PTSD symptoms, Openness to experience, and positive coping were significant predictors of PTG. The findings emphasize that when promoting PTG of accidentally injured patients, healthcare providers should facilitate patients utilizing personal resources, understand PTG coexists with PTSD symptoms, and adjust interventions based on the coping styles the patients have adopted. 相似文献
218.
Flashing a homogeneous light mask after the presentation of a masked target reduces the deleterious effects of the mask, a phenomenon often called target recovery. Target recovery has been studied using masking paradigms in which a target object is presented in isolation prior to the presentation of a mask, thus capturing attention. In the present study, we examined whether target recovery is possible when a target does not benefit from attentional capture. We hypothesized that target recovery would be eliminated when a target must compete with distractors for perceptual attention. Replicating classic studies, we observed target recovery when pattern and light masks followed an isolated target. However, target recovery was not observed when a light mask followed a masked visual search target. Furthermore, using an attentional-capture paradigm we found that sudden onset search targets were recoverable whereas nononset targets were not. The present findings indicate that attentional capture by a target prior to masking plays a critical role in the subsequent recovery of the target. 相似文献
219.
探讨个人幸福指数-中小学生版(PWI-SC)在中国的适用性以及中澳两国中学生个人幸福指数的跨文化差异。采用PWI-SC施测522名中国中学生、185名澳洲中学生,进行区分度、信度和效度检验,发现该问卷可运用于中国中学生个人幸福指数的调查,个别项目需稍加修改。比较中澳中学生的施测结果,中国中学生的个人幸福指数低于澳洲中学生,中国中学生得分为47-70,澳洲中学生得分为51-72;中国中学生除在个人已有成就项目上得分高于澳洲中学生外,其他方面均较低;中澳两国初中生的个人幸福指数均显著高于高中生,两国初高中生个人幸福指数的差异体现在不同方面;中澳两国中学生个人幸福指数的年龄差异均显著,进一步事后分析发现,两国中学生个人幸福指数的基本趋势均为随年龄增长,个人幸福指数降低,中国15岁中学生的个人幸福指数较高。PWI-SC基本适用于中国中学生;中学生随年龄增长,个人幸福指数降低;中国中学生的个人幸福指数低于澳洲中学生。 相似文献
220.