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51.
In January of 2007, freezing temperatures destroyed citrus and vegetable crops in California. By May 2007, more than 9,000 freeze‐related unemployment applications had been filed. Through face‐to‐face interviews, this study documents the experience of 63 farmworkers to find out how they survived the freeze and accessed services. Findings revealed that more than half of the interviewees did not seek benefits from the governmental One‐Stop centers set up to help them. Less than 10% of interviewees stated the benefits had covered their needs. Creating simple, nonbureaucratic guidelines for assisting affected individuals emerged as a need.  相似文献   
52.
Abstract

The icosahedral quasicrystals i-AIMn, isomorphically substituted by 28 at.% Fe or by a mixture of (CrFe) atoms, have been studied for the first time by in-field Mössbauer spectroscopy in order to determine the sign and asymmetry parameter of the dominant electric-field gradient (EFG) term. In addition, the orthorhombic o-Al(MnFe) and cubic α- and hexagonal β-Al(MnFe)Si crystalline phases have been studied. We show that the previous Mössbauer results are inadequate for determining whether there are two sites in the quasicrystalline structure in the ratio of the golden number. Our results for i-Al(MnFe) show that the dominant EFG is negative, with an asymmetry parameter of about 0·6. For i-Al(CrFe), essentially no deviations are found from the model of Czjzek or the Gaussian isotropic model. One crystalline phase, the hexagonal β phase, is found to have a very similar quadrupole effect to that found in i-Al(MnFe). In addition it is found that this phase undergoes a change which is at least partly of magnetic origin.  相似文献   
53.
Relations between constructs are estimated based on correlations between measures of constructs corrected for measurement error. This process assumes that the true scores on the measure are linearly related to construct scores, an assumption that may not hold. We examined the extent to which differences in distribution shape reduce the correlation between true scores on a measure and scores on the underlying construct they are intended to measure. We found, via a series of Monte Carlo simulations, that when the actual construct distribution is normal, nonnormal distributions of true scores caused this correlation to drop by an average of only .02 across 15 conditions. When both construct and true score distributions assumed different combinations of nonnormal distributions, the average correlation was reduced by .05 across 375 conditions. We conclude that theory‐based scales intended to measure constructs usually correlate highly with the constructs they are constructed to measure. We show that, as a result, in most cases true score correlations only modestly underestimate correlations between different constructs. However, in cases in which the two constructs are redundant, this underestimation can lead to the false conclusion that the constructs are ‘correlated but distinct constructs,’ resulting in construct proliferation.  相似文献   
54.
55.
Resumen

El objetivo de esta investigación es analizar el efecto del contexto lingüístico en la comprensión de las oraciones con ambigüedad estructural superficial. La tarea utilizada para este propósito ha sido de reconocimiento del significado adecuado al contexto presentado. Los resultados obtenidos muestran que efectivamente el contexto desempeña an papel determinante en la eliminación de la ambigüedad.  相似文献   
56.
The current study investigated the use of frames of reference in an asymmetrical spatial dialogue task. Participants navigated through a real environment by following instructions provided by other participants guiding them over the phone. The dialogues were transcribed and analysed to locate the introduction of landmarks. We examined which frames of reference were used to introduce these landmarks and how far their use was determined by each participant's role within the dyads (i.e. guide vs. guided person). Results revealed that both partners contributed to the dialogue by introducing landmarks. However, the guides introduced more landmarks than the guided persons and were also more likely to use perspective taking when doing so. These results are discussed in the light of perspective taking and collaboration in dialogue. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
57.
Any postpartum mental disorder in a mother can influence the mother-child relationship and communication and lead to the development of psychosomatic disorders or disorders of behavioral regulation with diagnostic status. These can have a long-term impact on the mother-child relationship and the child’s mental development. Based on research findings on mother-child interaction, the authors expound why including the child in treatment is crucial. Accordingly, possible contraindications for mother-infant treatment are described. Clinical parent-infant treatment practice is reviewed as an interdisciplinary and multiprofessional challenge and the necessity of adhering to minimum standards, beside adult psychiatric skills, of child psychiatric and developmental expertise in diagnostics and intervention for quality assurance.  相似文献   
58.

Indentations have been made on a (011) surface of GaAs single crystal at room temperature. The loading-unloading curves were compared with those obtained under the same experimental conditions on (001) surfaces. The indents formed were observed by transmission electron microscopy in plan view as well as in cross-sectional view in samples prepared by the focused-ion-beam technique. The gliding systems could be identified, providing a better understanding of the plastic flow under the indenter. The arrangements of dislocations generated by the indenter have been analysed and compared with results previously reported by Ning et al.  相似文献   
59.
Animals may memorise spatial and social information for many months and even years. Here, we investigated long-term memory of hierarchically ordered relationships, where the position of a reward depended on the relationship of a stimulus relative to other stimuli in the hierarchy. Seventeen greylag geese (Anser anser) had been trained on discriminations between successive pairs of five or seven implicitly ordered colours, where the higher ranking colour in each pair was rewarded. Geese were re-tested on the task 2, 6 and 12 months after learning the dyadic colour relationships. They chose the correct colour above chance at all three points in time, whereby performance was better in colour pairs at the beginning or end of the colour series. Nonetheless, they also performed above chance on internal colour pairs, which is indicative of long-term memory for quantitative differences in associative strength and/or for relational information. There were no indications for a decline in performance over time, indicating that geese may remember dyadic relationships for at least 6 months and probably well over 1 year. Furthermore, performance in the memory task was unrelated to the individuals’ sex and their performance while initially learning the dyadic colour relationships. We discuss possible functions of this long-term memory in the social domain.  相似文献   
60.
伤害回避是指个体对厌恶刺激信号做出强烈的反应,并学会被动地回避惩罚的一种倾向,这一倾向使得个体反复思考未来的结局,并谨慎小心地对待不确定情景中的事件,进而更有可能诱发情感障碍。伤害回避涉及的神经网络包括三个子网络,即额顶叶-前扣带皮层的连接、皮层-杏仁核的连接和白质通道的结构性连接,这三个子网络分别与羞怯感-易疲劳性、预期担心以及不确定环境中的害怕情绪有关。而其生物基础则包括单一基因多态性和基因多态间的交互作用。今后的研究应该集中在深化伤害回避神经网络与生物基础间的联合机制、研究三种及以上基因多态间的交互作用、考察其他因素对基因效应的调节作用、注重伤害回避四种亚型相关神经网络之间的连接、探讨5-HT4等其他几种5-羟色胺受体多态性与伤害回避的关系以及分析伤害回避内部机制在抗抑郁治疗中的作用等方面。  相似文献   
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