1,883 research outputs found

    Accurate evaluation of the interstitial KKR-Green function

    Full text link
    It is shown that the Brillouin zone integral for the interstitial KKR-Green function can be evaluated accurately by taking proper care of the free-electron singularities in the integrand. The proposed method combines two recently developed methods, a supermatrix method and a subtraction method. This combination appears to provide a major improvement compared with an earlier proposal based on the subtraction method only. By this the barrier preventing the study of important interstitial-like defects, such as an electromigrating atom halfway along its jump path, can be considered as being razed.Comment: 23 pages, RevTe

    Continuous twin screw rheo-extrusion of an AZ91D magnesium alloy

    Get PDF
    © The Minerals, Metals & Materials Society and ASM International 2012The twin screw rheo-extrusion (TSRE) is designed to take advantage of the nondendritc microstructure and thixotropic characterization of semisolid-metal slurries and produce simple metal profiles directly from melts. The extrusion equipment consists of a rotor-stator high shear slurry maker, a twin screw extruder, and a die assembly. The process is continuous and has a potential for significantly saving energy, manufacturing cost, and enhancing efficiency. The present investigation was carried out to study the process performance for processing rods of an AZ91D magnesium alloy and the microstructure evolution during processing. The semisolid slurry prepared by the process was characterized by uniformly distributed nondendritic granular primary phase particles. AZ91D rods with uniform and fine microstructures and moderate mechanical properties were produced. For the given slurry making parameters, decreasing extrusion temperature was found to improve microstructures and properties. The mechanisms of particle granulation and refinement and the effect of processing parameters on process performance and thermal management are discussed. © 2012 The Minerals, Metals & Materials Society and ASM International.EPSRC (UK) and Rautomead Lt

    Evaluating the longitudinal effect of colorectal surgery on health-related quality of life in patients with colorectal cancer.

    Get PDF
    Background and Objectives Surgery for colorectal cancer (CRC) negatively affects health-related quality of life (HRQoL). Addressing shortcomings in literature, the purpose of this study was to evaluate the impact of surgery for CRC on the course of HRQoL from baseline up to 2 years after diagnosis. Methods In this prospective, population-based study patients with newly diagnosed CRC were included between 2016 and 2019. HRQoL was assessed by the EORTC QLQ-C30 questionnaire over time both between and within subgroups of patients that underwent right-sided colonic, left-sided colonic, and rectal resection using linear mixed model analyses. Results The study included 415 patients of whom 148 patients underwent right-sided colonic (36%), 147 left-sided colonic (35%), and 120 rectal resection (29%). Overall, HRQoL scores restored to baseline level 1 year after diagnosis. Impact of surgery seems to be more prominent in patients who underwent rectal resection, as they experienced more pain and had worse role and social functioning scores 4 weeks after surgery. Finally, among patients who underwent left-sided and rectal resection, physical functioning did not return to baseline level during follow-up. Conclusion This study shows several differences (between-group and within-group) in HRQoL according to surgery type and offers perspective which patients may need additional support in the care pathway

    Dose-effect relations in time-limited combined psycho-pharmacological treatment for depression

    Get PDF
    BACKGROUND: A limited number of psychotherapy sessions in combination with medication is preferable to pharmacotherapy only in the treatment of ambulatory patients with major depression. Whether there is a relation between the number of sessions and the efficacy of the treatment is uncertain. METHOD: Randomized clinical trial comparing two treatment conditions in outpatients with major depression. All patients studied had a baseline score of at least 14 points on the 17-item Hamilton Depression Rating Scale. The two conditions consist of 8-session or 16-session Short Psychodynamic Supportive Psychotherapy, both in combination with pharmacotherapy. Efficacy was assessed using the 17-item HDRS, the CGI of Severity and of Improvement, the depression subscale of the SCL-90 and the Quality of Life Depression Scale. RESULTS: The rate of change would seem to indicate that eight sessions are preferable for both moderately and severely depressed patients, although the results converged again at the end. Furthermore, in terms of satisfaction with the number of sessions and drop-out percentages during treatment, no differences were found between the conditions. CONCLUSION: In the light of the outcome analysis (faster remission after fewer sessions), a short version of the psychotherapy treatment in a combined course of treatment seems to be justifie

    Person-Specific Non-shared Environmental Influences in Intra-individual Variability : A Preliminary Case of Daily School Feelings in Monozygotic Twins

    Get PDF
    Most behavioural genetic studies focus on genetic and environmental influences on inter-individual phenotypic differences at the population level. The growing collection of intensive longitudinal data in social and behavioural science offers a unique opportunity to examine genetic and environmental influences on intra-individual phenotypic variability at the individual level. The current study introduces a novel idiographic approach and one novel method to investigate genetic and environmental influences on intra-individual variability by a simple empirical demonstration. Person-specific non-shared environmental influences on intra-individual variability of daily school feelings were estimated using time series data from twenty-one pairs of monozygotic twins (age = 10 years, 16 female pairs) over two consecutive weeks. Results showed substantial inter-individual heterogeneity in person-specific non-shared environmental influences. The current study represents a first step in investigating environmental influences on intra-individual variability with an idiographic approach, and provides implications for future behavioural genetic studies to examine developmental processes from a microscopic angle
    • …
    corecore