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181.
Previous research has investigated the effect of maternal soothing behaviors on reducing infant reactivity but not the differential effects of specific maternal behaviors on infant stress responses. The present study investigated maternal regulation of 2- and 6-month-olds' responses to an inoculation and found a significant decline with age in both the intensity and duration of infants' crying. Maternal affection and touching decreased from 2 to 6 months, whereas maternal vocalizing and distraction behaviors increased. At both ages, the combination of maternal holding/rocking and vocalizing was associated with decreases in all levels of infant reactivity. Neither strategy alone, however, was found to be effective. Feeding/ pacifying behaviors were effective only when initial distress was at a low or moderate level, which suggests that the effectiveness of maternal regulatory behaviors may depend on the intensity of infants' crying. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
182.
The authors used model-based cluster analysis to identify subtypes of criminal psychopaths on the basis of differences in personality structure. Participants included 96 male prisoners diagnosed as psychopathic, using the Psychopathy Checklist Revised (PCL-R; R. D. Hare, 1991). Personality was assessed using the brief form of the Multidimensional Personality Questionnaire (MPQ-BF; C. J. Patrick, J. J. Curtin, & A. Tellegen, 2002). The best-fitting model yielded two clusters. Emotionally stable psychopaths were characterized by low Stress Reaction and high Agency. Aggressive psychopaths were characterized by high Negative Emotionality, low Constraint, and low Communion. These results suggest that psychopaths as defined by the PCL-R includes distinct subtypes, distinguishable in terms of personality structure, that may reflect different etiologies. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
183.
Questionnaire data from 2,033 participants in the National Anxiety Disorders Screening Day sample were used to assess the presence of panic and comorbid anxiety problems. These participants were selected from more than 15,000 attendees on the basis of never having received treatment for a psychiatric disorder and meeting screening criteria for panic disorder. With each comorbid anxiety problem (generalized anxiety disorder, posttraumatic stress disorder, social phobia, and obsessive-compulsive disorder), participants had a corresponding increase in interference in daily living as well as readiness to seek treatment. The addition of generalized anxiety or depression with panic symptoms resulted in marked increases in interference scores. Clinical treatment implications for panic disorder are discussed in terms of the effects of comorbid anxiety problems. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
184.
Although word stress has been hailed as a powerful speech-segmentation cue, the results of 5 cross-modal fragment priming experiments revealed limitations to stress-based segmentation. Specifically, the stress pattern of auditory primes failed to have any effect on the lexical decision latencies to related visual targets. A determining factor was whether the onset of the prime was coarticulated with the preceding speech fragment. Uncoarticulated (i.e., concatenated) primes facilitated priming. Coarticulated ones did not. However, when the primes were presented in a background of noise, the pattern of results reversed, and a strong stress effect emerged: Stress-initial primes caused more pruning than non-initial-stress primes, regardless of the coarticulatory cues. The results underscore the role of coarticulation in the segmentation of clear speech and that of stress in impoverished listening conditions. More generally, they call for an integrated and signal-contingent approach to speech segmentation. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
185.
使用有限元程序对聚变次临界堆双冷嬗变包层第一壁进行数值模拟 ,给出不同载荷条件下的温度场和应力场分布 ,结果证明典型氦气系统设计满足热工要求。依据数值模拟结果对第一壁氦气载热能力进行分析 ,并考虑了流道形状对结构热应力的影响。  相似文献   
186.
按照生态农业工程理论和抗旱节水工程技术要求,对棉花转基因抗旱品种、不同密度、不同基肥N、P的施用量进行田间水分胁迫综合试验.经在关中灌区3年试验研究结果表明:密度以每公顷种植7.5万株比种植4.5、6万株分别增产671.854、83.30 kg,增产57.49%和41.36%.品种陕402(早熟)、陕576(中早熟)分别比中棉所41(中熟)增产16.62%和16.17%.施磷酸二铵比尿素增产,每公顷施1502、25 kg分别增产11.35%和10.53%.抗旱节水农业工程育种和农艺节水工程技术结合,不仅可降低生产成本44%~47%,还可提高产量和品质,增收1 050~5 000元/hm2,同时节约了水资源,保护了农业生态环境.  相似文献   
187.
根据厚壁圆筒形压力容器开孔应力集中系数的一般表达式,利用正交函数展开的方法,将厚壁圆柱壳的开孔应力问题简化为求解一组无穷代数方程组问题为说明复变函数分析方法的适用性,给出了圆筒形压力容器在自由边界条件下,开圆孔和椭圆孔应力集中系数的数值结果  相似文献   
188.
电测技术在人体骨骼力学性能分析中的应用   总被引:2,自引:0,他引:2  
用电测实验应力分析方法,对人体管状长骨的力学性质,以及骨折的钢板皮外固定治疗中的力学问题,进行测量与分析。其结果对于推进力学理论在医学方面的应用,以及临床治疗骨折,具有实用价值。  相似文献   
189.
In order to investigate stress corrosion cracking (SCC) of X70 pipeline steel and its weld joint area in acidic soil environ-ment in China, two simulating methods were used: one was to obtain bad microstructures in heat affected zone by annealing at 1300°C for 10 min and then, quenching in water; the other was to get different simulating solutions of acidic soil in Yingtan in south-east China. The SCC susceptibilities of X70 pipeline steel before and after quenching in the simulating solutions were analyzed...  相似文献   
190.
避免出料管破裂或断裂是保证核废料高放废液玻璃固化进程的重要措施之一。通过建立力学模型,分析了服役工况下不同因素对出料管的受力作用及应力大小。结果表明,熔融高放废液玻璃固化料静水压力作用和玻璃固化料及出料管自重作用导致的出料管最大拉应力,远小于出料管不同服役温度时对应的拉伸强度,其对出料管破裂风险影响极低。出料管在停止出料阶段,同时承受固化料对其作用的静水压力和内外壁温差导致的热应力叠加作用,由此导致的最大拉应力分布在出料管内壁,且足以对出料管产生明显不利影响。通过对出料管内、外径进行优化设计,可降低服役过程中导致的最大拉应力值,从而保障出料管的安全可靠应用。  相似文献   
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