Numerical Modeling of Grain Boundary Effects in the Diffusional Creep of Copper Interconnect Lines

We propose a numerical simulation technique to model the process of diffusional creep and stress relaxation that occurs in Cu-damascene interconnects of integrated circuit devices in processing stage. The mass flow problem is coupled to the stress analysis through vacancy flux and equilibrium vacancy concentration. The technique is implemented in a software package that seamlessly integrates the problem-oriented code with commercially available finite element program MSC.Marc. It is utilized to model the Coble creep phenomenon by introducing the nanoscale grain boundary region having the thickness on the order of several layers of atoms. As an illustration, the two-dimensional problem of stress relaxation in a single grain subjected to prescribed displacements and tractions is examined.     

Ethnicity, Expressed Emotion, Attributions, and Course of Schizophrenia: Family Warmth Matters.

The authors examined the role of family factors and the course of schizophrenia by carrying out additional assessments and analyses in 2 previously published studies of Mexican American and Anglo American patients and families. The authors found partial support for an attributional model of relapse for families who are low in emotional overinvolvement. Attributions of control, criticism, and warmth together marginally predicted relapse. The data also indicated that for Mexican Americans, family warmth is a significant protective factor, whereas for Anglo Americans, family criticism is a significant risk factor. These findings suggest that the sociocultural context shapes the pathways by which family processes are related to the course of illness. Moreover, the warmth findings suggest that families may contribute to preventing relapse. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Seismic Deformation of Bar Mat Mechanically Stabilized Earth Walls. II: A Multiblock Model

A relatively simple rigid plastic multiblock computational model has been developed to predict the permanent seismic displacement of mechanically stabilized earth (MSE) walls. The model formulation was based on many observations made from a series of centrifuge tests carried out on many different configurations of MSE walls. The proposed model is similar to the sliding block method of Newmark. The approach accounted for the variation in acceleration within the backfill and the nonuniform nature of the permanent wall face deformation. The predictive capability of the proposed model has been verified using centrifuge test results obtained for four MSE walls each subjected to three earthquake excitations with strength varying between 0.48 and 0.9g. The analytical model captures many aspects of the characteristic deformation behavior of MSE walls observed in the centrifuge tests. In each of the eleven wall displacement cases studied, the backfill friction angle that yielded a good match between the computed and measured maximum wall displacement was consistent with the corresponding laboratory measured values.     

A Comparison of Narrative Exposure Therapy, Supportive Counseling, and Psychoeducation for Treating Posttraumatic Stress Disorder in an African Refugee Settlement.

Little is known about the usefulness of psychotherapeutic approaches for traumatized refugees who continue to live in dangerous conditions. Narrative exposure therapy (NET) is a short-term approach based on cognitive-behavioral therapy and testimony therapy. The efficacy of narrative exposure therapy was evaluated in a randomized controlled trial. Sudanese refugees living in a Ugandan refugee settlement (N = 43) who were diagnosed as suffering from posttraumatic stress disorder (PTSD) either received 4 sessions of NET, 4 sessions of supportive counseling (SC), or psychoeducation (PE) completed in 1 session. One year after treatment, only 29% of the NET participants but 79% of the SC group and 80% of the PE group still fulfilled PTSD criteria. These results indicate that NET is a promising approach for the treatment of PTSD for refugees living in unsafe conditions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Application of confocal scanning laser microscopy in experimental pathology

Confocal scanning laser microscopy (CSLM) represents an exciting new tool for scientific disciplines which focus on mechanistic studies such as experimental pathology. Enhanced resolution in the specimen plane and rejection of out-of-focus fluorescence flare allow analysis of specific nucleic acid sequences, enzymes, structural macromolecules, and cellular homeostasis utilizing fluorescent probes. Four different experimental applications are discussed which utilize CSLM to evaluate pathological processes at the subcellular, cellular, and tissue levels. Programmed cell death, or apoptosis, is a natural process of significance both during development and as a response to toxic stimuli. CSLM-imaging of nuclei of human B lymphoblastoid cells following exposure to a monofunctional alkylating agent suggests that the degradation of chromatin characteristic of apoptosis may occur in asymmetric patterns. Surfactant apoprotein-A is the major non-serum protein component of pulmonary surfactant and is essential for the extracellular function of surfactant. CSLM of alveolar type II cells suggests that apoprotein-A is present in both the cytoplasm, predominantly in lamellar bodies, and in the nucleus. The tumor promoter, phorbol myristate acetate, rapidly stimulated the formation of vacuoles in human neutrophils. CSLM using Lucifer Yellow as a probe suggests that cylindrical vacuoles are formed by fluid-phase pinocytosis. The blood-nerve barrier (BNB) in peripheral nerves may be an important target during toxin-induced neuropathies. Ricin-induced permeability of the BNB in the rat was rapidly visualized by CSLM as leakage of fluorescein isothiocynate (FITC)-dextran into the endoneurial compartment.     

What results when firms implement practices: The differential relationship between specific practices, firm financial performance, customer service, and quality.

Previous research on organizational practices is replete with contradictory evidence regarding their effects. Here, the authors argue that these contradictory findings may have occurred because researchers have often examined complex practice combinations and have failed to investigate a broad variety of firm-level outcomes. Thus, past research may obscure important differential effects of specific practices on specific firm-level outcomes. Extending this research, the authors develop hypotheses about the effects of practices that (a) enable information sharing, (b) set boundaries, and (c) enable teams on 3 different firm-level outcomes: financial performance, customer service, and quality. Relationships are tested in a sample of observations from over 200 Fortune 1000 firms. Results indicate that information-sharing practices were positively related to financial performance 1 year following implementation of the practices, boundary-setting practices were positively related to firm-level customer service, and team-enabling practices were related to firm-level quality. No single set of practices predicted all 3 firm-level outcomes, indicating practice-specific effects. These findings help resolve the theoretical tension in the literature regarding the effects of organizational practices and offer guidance as to how to best target practices to increase specific work-related outcomes. Implications for theory, research, and practice are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Fitting in and feeling fine: Conformity and coping motives as mediators of the relationship between social anxiety and problematic drinking.

The present research was conducted to clarify the relationships among social anxiety, alcohol consumption, alcohol-related problems, and negative-reinforcement drinking motives among college students. Heavy drinking students (N = 316, 53.80% female) completed self-report measures of social anxiety, alcohol consumption, alcohol-related problems, and drinking motives. Findings indicated that students higher in social anxiety consumed less alcohol but experienced more negative consequences. Moreover, the relationship between social anxiety and negative consequences was mediated by coping and conformity drinking motives in addition to alcohol consumption. In the context of social anxiety, the current research demonstrates the importance of examining problematic drinking as distinct constructs: alcohol consumption and negative consequences. Findings are also discussed in terms of implications for interventions with socially anxious students. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

An analysis of EMG electrode configuration for targeted muscle reinnervation based neural machine interface.

Targeted muscle reinnervation (TMR) is a novel neural machine interface for improved myoelectric prosthesis control. Previous high-density (HD) surface electromyography (EMG) studies have indicated that tremendous neural control information can be extracted from the reinnervated muscles by EMG pattern recognition (PR). However, using a large number of EMG electrodes hinders clinical application of the TMR technique. This study investigated a reduced number of electrodes and the placement required to extract sufficient neural control information for accurate identification of user movement intents. An electrode selection algorithm was applied to the HD EMG recordings from each of four TMR amputee subjects. The results show that when using only 12 selected bipolar electrodes the average accuracy over subjects for classifying 16 movement intents was 93.0 (+/-3.3)%, just 1.2% lower than when using the entire HD electrode complement. The locations of selected electrodes were consistent with the anatomical reinnervation sites. Additionally, a practical protocol for clinical electrode placement was developed, which does not rely on complex HD EMG experiment and analysis while maintaining a classification accuracy of 88.7+/-4.5%. These outcomes provide important guidelines for practical electrode placement that can promote future clinical application of TMR and EMG PR in the control of multifunctional prostheses.     

Computer use in the elementary classroom: A survey of computer contact persons in four school districts

This article investigates the use of computers in the elementary classroom. The research involved a review of some literature and field research done at schools in four chosen school districts in Toronto and Vancouver. A questionnaire was distributed and interviews were conducted with elementary school teachers and district consultants. From this field research, information was collected on the availabilities of hardware, software, teacher implementation, as well as on teachers' perceptions on computer use in the classroom. The survey results illustrate the state of computer use in some elementary schools. The findings provide implications for integrating computer use into the curriculum, and lays the groundwork for further research on how best to use the technology for elementary education.