CuIn(S,Se)2thin film solar cells from nanocrystal inks: Effect of nanocrystal precursors

CuIn(S,Se)₂ thin film solar cells are fabricated by selenizing CuInS₂ nanocrystals synthesized using a variety of copper and indium precursors. Specifically, copper and indium acetates, acetylacetonates, iodides, chlorides and nitrates are investigated to determine the effect of precursors on electronic properties and device performance. Nanocrystal synthesis with each of these precursors can be optimized to yield similar nanocrystal composition, size and structure. In addition, dense chalcopyrite CuIn(S,Se)₂ thin films with micron sized grains at the surface are formed upon selenization regardless of precursor type. Surprisingly, solar cells fabricated from each nanocrystal ink have roughly the same carrier concentrations of 10¹⁶ to 10¹⁷ cm^− 3 in the absorber layer and achieve active area efficiencies of approximately 5%.     

Optimum synchronisation preamble design

A performance model for the detection of binary synchronisation preambles embedded in random data is described. This model identifies the three original Barker sequences as optimum preambles. However, the model also indicates that the performances of the remaining Barker codes are suboptimum, and alternatives having improved synchronisation performances are presented.<>     

Posttraumatic headache: neuropsychological and psychological effects and treatment implications

Posttraumatic headache (PTHA) is a frequent occurrence following trauma to the head, brain, and/or neck. Estimates of persistence for 6 months are as high as 44%. Review of available studies examining the effect of headache on neuropsychological test findings reveals that chronic headache pain, and chronic pain generally, exerts a significant and negative effect that poses a challenge to differential diagnostic efforts in the evaluation of mild brain injury. Given that PTHA is the most common postconcussive symptom and most frequent type of posttraumatic pain associated with mild traumatic brain injury (TBI), it follows that resolution of the postconcussion syndrome, and successful posttraumatic adaptation, may frequently rely on success in coping with PTHA symptomatology. Viewing PTHA from a biopsychosocial perspective, a general outline is offered for improving both assessment and treatment of PTHA. In addition, the most promising psychology-based treatment interventions are reviewed.     

Trajectories of psychosocial adjustment in adolescents with spina bifida: A 6-year, four-wave longitudinal follow-up.

Objective: As a follow-up to an earlier cross-sectional study (Holmbeck et al., 2003), the current multimethod, multi-informant investigation examined individual growth in psychosocial adjustment across the adolescent transition in 2 samples: young adolescents with spina bifida (SB) and typically developing adolescents (N = 68 in both groups at Time 1). Method: Growth curve modeling procedures were used to describe the developmental course of psychosocial adjustment across 4 waves of data collection from ages 8 to 15. Child gender was included in the models as a moderator of associations between illness status and adjustment trajectories. Results and Conclusions: Findings revealed that preadolescent differences between groups were maintained for several adjustment variables, indicating that adolescents with SB have enduring academic and attention problems and difficulties with social development (e.g., fewer friends and less influence during family interactions). For other outcomes, trajectories of adjustment levels for adolescents with SB converged on levels observed in comparison adolescents, indicating some areas of resilience. Girls with SB were at risk for increasing levels of social difficulties and negative perceptions of their physical appearance. Clinical implications are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

alphadbeta2 integrin is expressed on human eosinophils and functions as an alternative ligand for vascular cell adhesion molecule 1 (VCAM-1)

The beta2 family of integrins, CD11a, CD11b, CD11c, and alphad, are expressed on most leukocytes. We show that the newest member of this family, alphad, is expressed on human eosinophils in peripheral blood, and surface expression can be upregulated within minutes by phorbol ester or calcium ionophore A23187. Culture of eosinophils with interleukin 5 (IL-5) leads to a two- to fourfold increase in alphad levels by 3-7 d without a change in alpha4 integrin expression. Eosinophils isolated from late phase bronchoalveolar lavage fluids express alphad at levels similar to that seen after 3 d of IL-5 culture. Regarding alphadbeta2 ligands, in both freshly isolated and IL-5-cultured eosinophils, as well as alphadbeta2-transfected Chinese hamster ovary cells, alphadbeta2 can function as a ligand for vascular cell adhesion molecule 1 (VCAM-1). This conclusion is based on the ability of monoclonal antibodies to alphad, beta2, or VCAM-1 to block cell attachment in static adhesion assays. In experiments with eosinophils, the relative contribution of alphadbeta2 integrin- mediated adhesion is enhanced after IL-5 culture. These experiments demonstrate that alphadbeta2 is an alternative ligand for VCAM-1, and this integrin may play a role in eosinophil adhesion to VCAM-1 in states of chronic inflammation.     

Effects of interparental aggression on children's adjustment: The moderating role of cognitive appraisal and coping.

This research examined the relationship between interparental aggression and children's adjustment through an analysis of the moderating effects of children's cognitive appraisal and coping strategies. Participants were 80 children in Grades 6, 7, and 8 who completed measures of level of interparental aggression and of cognitive appraisal and coping strategies reported in response to parents' conflicts. Children's adjustment was based on self-report measures of self-worth, externalizing behavior, and depression. Results showed that more frequent and intense conflict was associated with greater adjustment problems for children. Problematic beliefs about interparental conflict and ineffective coping strategies were also related to greater maladjustment. Significant interaction effects suggest that perceived peer availability and the use of social supports may buffer the negative effects of marital conflict. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Adolescent health psychology.

In this article, a biopsychosocial model of adolescent development is used as an organizing framework for a review of primary, secondary, and tertiary prevention research with adolescent populations. During adolescence many critical health behaviors emerge, affecting future disease outcomes in adulthood. In addition, most of the predominant causes of morbidity and mortality in adolescence are unique to this period of development, indicating that health-focused interventions must be tailored specifically to adolescents. Moreover, it is during adolescence that lifelong patterns of self-management of and adjustment to chronic health conditions are established. Thus, an increased focus on adolescence in health psychology research is important both to improve the health of adolescents per se and to optimize health trajectories into adulthood. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Success and failure in the behavioral treatment of obsessive-compulsives.

Attempted to construct a model for predicting success and failure in the behavioral treatment (exposure and response prevention) of obsessive-compulsives (N?=?50, mean age 34 yrs). Three sets of variables—demographic, pretreatment level of neurotic symptomatology, and S's responses during exposure sessions—were examined. Seven variables were found to be related to outcome at posttreatment and/or at follow-up: Pretreatment level of depression and of anxiety, reactivity, and habituation of reported anxiety to feared stimuli within- and between-sessions were all found to affect outcome at posttreatment. Posttreatment outcome as well as age at symptom onset were significantly related to maintenance of gains. A model of the interrelationships of these variables was constructed and tested by a path analysis. (33 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)