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831.
I. Ratschinski H.S. Leipner F. Heyroth W. Fränzel R. Hammer M. Jurisch 《Philosophical Magazine Letters》2013,93(8):565-571
Single-crystal (0 0 0 1) GaN samples have been deformed with a Vickers indenter at room temperature using loads in the range from 0.02 to 4.90 N. Dislocations and cracks at the indentations were examined by means of scanning electron microscopy, cathodoluminescence, light microscopy and transmission electron microscopy. Geometrical relations could be found between the dislocation arrangement, cracks and the orientation of the indenter. The orientation of the indenter has only a slight effect on the dislocation pattern, but the crack system is predominantly determined by the symmetry and the orientation of the indenter. 相似文献
832.
The Vickers hardnesses of 15 semiconductors, namely Si, Ge, SiC, AlN, GaN, GaP, GaAs, GaSb, InP, InAs, InSb, ZnO, ZnSe, ZnTe and CdTe, have been investigated from room temperature to their melting points. The temperature dependences of the Vickers hardness H V of 11 of these semiconductors, namely those with a cubic structure, obey a universal relationship when H V and the temperature T are scaled respectively by the shear modulus G and by Gb 3 / k B, with b being the magnitude of the Burgers vector. The scaling rule is the same as that found for the temperature dependence of the critical shear stress c for the {111}<110> slip system, satisfying the relationship H V = (70-100) c . 相似文献
833.
P. Shang G. Yang I.P. Jones C.E. Gough J.S. Abell K. Nadarzinski 《Philosophical Magazine Letters》2013,93(9):741-745
The position of Dy in the unit cell of Bi2Sr2CaCu2Oy has been determined by a real-space method. This is compared with the reciprocal-space atom location by channelling-enhanced microanalysis (ALCHEMI) method. 相似文献
834.
I. A. Ovid'ko 《Philosophical Magazine Letters》2013,93(10):611-620
The notion of nanodefects (topological defects of nanoscale translational order) in nanostructures of various types is introduced. Experimental data reported in the literature are discussed giving direct evidence for the existence of nanodefects in self-assembled periodically ordered nanostructures such as arrays of quantum dots, self-assembled superlattice films of nanoparticles, and arrays of carbon nanotubes. Also, the specific geometric features of perfect and partial cellular dislocations (being a kind of nanodefect) and their role in superplastic deformation in nanocrystalline materials are considered. 相似文献
835.
Christopher P. Fairholme Elizabeth L. Nosen Yael I. Nillni Julie A. Schumacher Matthew T. Tull Scott F. Coffey 《Behaviour research and therapy》2013,51(9):540-546
Sleep disturbance and emotion dysregulation have been identified as etiologic and maintaining factors for a range of psychopathology and separate literatures support their relationships to anxiety, depression, PTSD, and alcohol dependence (AD) symptom severity. Previous studies have examined these relationships in isolation, failing to account for the high rates of comorbidity among disorders. It is not yet known whether these processes uniquely predict symptom severity in each of these domains. Participants were 220 patients in residential substance abuse treatment, who had experienced a potentially traumatic event and exceeded screening cutoffs for probable PTSD and problematic alcohol use. Controlling for emotion dysregulation and the interrelationships among the outcome variables, insomnia was uniquely associated with anxiety (B = .27, p < .001), depression (B = .25, p < .001), PTSD (B = .22, p < .001), and AD (B = .17, p = .01) symptom severity. Similarly, controlling for insomnia, emotion dysregulation was uniquely associated with anxiety (B = .40, p < .001), depression (B = .47, p < .001), PTSD (B = .38, p < .001), and AD (B = .26, p < .001) symptom severity. Insomnia and emotion dysregulation appear to be transdiagnostic processes uniquely associated with symptom severity across a number of different domains and might be important treatment targets for individuals with PTSD and AD. 相似文献
836.
George I. Mamboleo Abdoulaye Diallo Robinson M. Ocharo Spalatin N. Oire Charlene M. Kampfe 《Journal of Psychology in Africa》2013,23(3):216-223
This study examined personal and contextual variables as predictors of attitudes toward disability at a Kenyan higher education setting. Participants were a convenience sample of 309 undergraduate students at a Kenyan university enrolled in Sociology, Social Work, Psychology, Political Science, and Public Administration majors. Data on attitudes were collected using the Attitudes Towards Disabled Persons scale (ATDP: Antonac & Livneh, 1988). A cross-sectional survey design was employed for data collection, and a multiple regression analysis was used for data analysis. Results revealed that the model was significant: F (9, 250)?=?2.784, p?=?0.004. However, only age (β?=?0.173, p?=?0.044) significantly predicted attitudes towards disability, indicating older students held more positive attitudes than their younger counterparts. Older students had a more favourable attitude towards people with disabilities than younger students. Seniority, by age, is highly valued in Africa than perhaps anywhere in the world. Kenyan older adults may be key to enhancing favourable attitudes toward individuals with disabilities in Kenya as well as interventions aimed at changing negative attitudes towards people with disabilities. 相似文献
837.
Gary I. Steele 《Journal of Psychology in Africa》2013,23(2):207-215
This article describes the translation of the Beck Depression Inventory-II, the Beck Hopeless Scale, and the Beck Anxiety Inventory, into Xhosa the language spoken in the Eastern Cape of South Africa. The processes of translation, back-translation and committee discussion failed to yield trustworthy translations because of practical difficulties in working with translators. Critical words and phrases were identified which gave rise to lack of agreement. For each, a range of options was generated and the advantages and disadvantages evaluated in terms of criteria such as conceptual and idiomatic equivalence, and extensiveness of usage. Examples are given of the problems encountered and the way in which final decisions were made. A pilot clinical trial demonstrated the acceptability of the translated instruments. Two further articles report the psychometric evaluation of the translated scales. 相似文献
838.
Gary I. Steele 《Journal of Psychology in Africa》2013,23(2):217-226
The Beck Depression Inventory-II (BDI-II), the Beck Anxiety Inventory (BAI), and the Beck Hopelessness Scale (BHS) were translated into Xhosa, a language widely spoken in South Africa to yield translated scales referred to as the XBDI-I (Xhosa BDI-II), the XBAI (Xhosa BAI) and the XBHS (Xhosa BHS). These scales were administered to a sample of 122 Xhosa respondents which included students and patients. The psychometric properties of the translated scales were comparable to those of the original English versions. Measures of internal consistency were as high as those for the validation studies in the USA and good item-scale correlations were obtained. This suggests that the translation yielded clinically useful scales which tap symptoms that are largely culturally universal. 相似文献
839.
Luis Felipe Rios Francisca Luciana de Aquino Miguel Muñoz-Laboy Cinthia Oliveira Richard G. Parker 《文化与宗教》2013,14(4):355-372
Religious beliefs have had a key role in shaping local responses to HIV and AIDS. As the world's largest Catholic country, Brazil is no exception. Yet little research has been conducted to document how religious doctrine is enacted in practice among its lay leaders and followers. In this article, we present ethnographic research from Recife, Brazil, conducted to understand the way in which religious doctrines are interpreted at a local level. Contextualised within the sociology of contemporary Brazilian Catholicism, we draw on interviews with clergy members, lay leaders, and parishioners to discuss how the Catholic Church's vision of sexuality translates into everyday lives of its followers. We explore the disjuncture between the Catholic ideals of fidelity and delaying sex until marriage with the everyday reality of the Church's followers, highlighting the role that gender plays in defining sexual roles and expectations. We conclude by posing questions for future research and HIV prevention strategies considering the formal institutional response of the Brazilian Catholic Church to AIDS on the one hand, and the social and cultural contexts in which Catholics live their daily lives on the other. 相似文献
840.
Mario I. Aguilar 《文化与宗教》2013,14(2):233-245
This paper examines some of the current ideas and methods that have problematised the study of religion within a globalised community. Religion and culture cannot be considered bounded entities, to be described as unchangeable. However, their constant process of change is not something new. It becomes new due to writing patterns and contemporary ideas on the relevance of religion or the creativity of culture. By analysing some discussions on possession cults, the paper suggests that ritual and performance constitute the moments when culture and religion are mediated. It is through ritual that religious practices are adapted, and it is in a ritual performance where culture is contested and challenged. Religion becomes ‘confused culture’, that once again is re‐organised and made orderly by reflection on ritual practices. Finally, the paper suggests that the agenda for an anthropology of religion for this new century is two‐fold. Firstly, to try to become more conversant with ever changing localised practices of ritual, and secondly, to try to converse about those practices with other practitioners and scholars from different fields and in different fields. 相似文献