151 research outputs found

    Affinity Constants of Naturally Acquired and Vaccine-Induced Anti-Pseudomonas aeruginosa Antibodies in Healthy Adults and Cystic Fibrosis Patients

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    Naturally acquired anti-Pseudomonas aeruginosa antibody fails to afford protection against repeated P. aeruginosa bronchopulmonary exacerbations in cystic fibrosis (CF) patients. In an effort to explain this phenomenon, the titer and affinity constants of serum anti-lipopolysaccharide (LPS) IgG were determined in five study groups: healthy adults before and after immunization with a polyvalent LPS-based vaccine, healthy noncolonized CF patients before and after immunization, nonimmunized CF patients with significantly elevated anti-LPS antibody titers without documented colonization, recently colonized CF patients before and after immunization, and nonimmunized CF patients chronically colonized with P. aeruginosa. Immunization elicited a significant rise in total anti-LPS immunoglobulin levels and affinity constants in both healthy adults and CF patients. Although chronically colonized patients had elevated levels of total anti-LPS antibody, these antibodies possessed affinities at least tOO-fold less than those of vaccine-induced antibodie

    Indirect Efficiency Determination and Parameter Identification of Permanent-Magnet Synchronous Machines

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    This thesis presents a method for efficiency determination of inverter-fed permanent-magnet synchronous machines by summation of the individual losses. For electrically excited synchronous machines there are already standardized methods, as for high efficiency values the direct procedure of input/output measurement is too inaccurate. With the novel method for machines in the base speed range, the individual losses are determined at the no-load experiment and the removed rotor test and recalculated for rated operation. The prerequisites and the analysis of the experiments are described. To evaluate the procedure, measurement series are performed on five different permanent-magnet synchronous machines with a rated power of 45 kW ... 160 kW. The indirect efficiency is compared with a direct measurement. Also for four of the five test machines finite element simulations are carried out to prove the assumptions of the proposed method. The result is, that for four of the test machines a good accordance with deviations below 0.5 % at rated operation conditions is reached. But because of the special design of the fifth test machine the losses and thus the efficiency show deviations of about 1 %. In total, the indirect procedure is usable as an adequate replacement for typical kinds of permanent-magnet synchronous machines with distributed windings and especially for big rated powers, where the direct method is too imprecise. In addition to the efficiency determination the thesis also shows, how to determine the no-load voltage, the short-circuit current, and the synchronous inductance by using the described experiments

    Exploring the Neural Basis of Avatar Identification in Pathological Internet Gamers and of Self-Reflection in Pathological Social Network Users

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    Background and aims Internet gaming addiction appears to be related to self-concept deficits and increased angular gyrus (AG)-related identification with one’s avatar. For increased social network use, a few existing studies suggest striatal-related positive social feedback as an underlying factor. However, whether an impaired self-concept and its reward-based compensation through the online presentation of an idealized version of the self are related to pathological social network use has not been investigated yet. We aimed to compare different stages of pathological Internet game and social network use to explore the neural basis of avatar and self-identification in addictive use. Methods About 19 pathological Internet gamers, 19 pathological social network users, and 19 healthy controls underwent functional magnetic resonance imaging while completing a self-retrieval paradigm, asking participants to rate the degree to which various self-concept-related characteristics described their self, ideal, and avatar. Self-concept-related characteristics were also psychometrically assessed. Results Psychometric testing indicated that pathological Internet gamers exhibited higher self-concept deficits generally, whereas pathological social network users exhibit deficits in emotion regulation only. We observed left AG hyperactivations in Internet gamers during avatar reflection and a correlation with symptom severity. Striatal hypoactivations during self-reflection (vs. ideal reflection) were observed in social network users and were correlated with symptom severity. Discussion and conclusion Internet gaming addiction appears to be linked to increased identification with one’s avatar, evidenced by high left AG activations in pathological Internet gamers. Addiction to social networks seems to be characterized by emotion regulation deficits, reflected by reduced striatal activation during self-reflection compared to during ideal reflection

    High-speed IPM Motors with Rotor Sleeve: Structural Design and Performance Evaluation

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    This paper deals with the structural design of sleeves for high-speed interior permanent magnet (IPM) synchronous machines. Wrapped IPM (WIPM) motors are a new player in the field of high-speed e-machines for traction, where a retaining sleeve is used to hold the magnetic poles in place against centrifugal forces, replacing the role of conventional iron bridges. The wrapping technique, originating from surface-mounted permanent magnet rotors, is believed to push speed limitations to new heights, as demanded by the increasing requirements of the automotive industry. By developing an equivalent rotor geometry of the WIPM rotor, an analytical model is formulated to evaluate the stress in the rotor and to provide a quick and intuitive tool for the sleeve design. The results are successfully validated by structural finite element analysis. Also, the output figures of a WIPM machine are compared to those of an equivalent IPM machine with iron bridges

    Design Guidelines for interlocked stator cores made of CoFe sheets

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    CoFe lamination stacks used for high-performance electric motors can be manufactured economically in high volumes by interlocking. In order to ensure sufficient joint strength with minimized sheet thickness, a comprehensive knowledge of the influences of various process parameters, such as embossing depth, clearance and counter punch force, is essential. To analyze these parameters, which also influence the magnetic properties, experiments are carried out and resulting joint strengths are determined in top tensile tests. The negative influences of the cutting process on magnetic conductivity and thus hysteresis losses due to residual stresses and plastic deformation are well known. In the subsequent stacking step, an influence of embossing and pre-stresses on the material properties is expected. In addition, local electrical contacts between the sheets may occur due to the interlocking process, causing additional eddy currents. Loss measurements are conducted to investigate the effect of the joining process on the magnetic properties of the stack. In doing so, the influence of process parameters such as the embossing depth and clearance on eddy current power losses is analyzed

    Transfer of manualized Short Term Psychodynamic Psychotherapy (STPP) for social phobia into clinical practice: study protocol for a cluster-randomised controlled trial

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    <p>Abstract</p> <p>Background</p> <p>Psychodynamic psychotherapy is frequently applied in the treatment of social phobia. Nevertheless, there has been a lack of studies on the transfer of manualized treatments to routine psychodynamic practice. Our study is the first one to examine the effects of additional training in a manualized Short Term Psychodynamic Psychotherapy (STPP) procedure on outcome in routine psychotherapy for social phobia. This study is an extension to a large multi-site RCT (N = 512) comparing the efficacy of STPP to Cognitive-Behavioral Therapy (CBT) of Social Phobia.</p> <p>Methods/Design</p> <p>The manualized treatment is designed for a time limited approach with 25 individual sessions of STPP over 6 months. Private practitioners will be randomized to training in manualized STPP vs. treatment as usual without a specific training (control condition). We plan to enrol a total of 105 patients (84 completers). Assessments will be conducted before treatment starts, after 8 and 15 weeks, after 25 treatment sessions, at the end of treatment, 6 months and 12 months after termination of treatment. The primary outcome measure is the Liebowitz Social Anxiety Scale. Remission from social phobia is defined scoring with 30 or less points on this scale.</p> <p>Discussion</p> <p>We will investigate how the treatment can be transferred from a controlled trial into the less structured setting of routine clinical care. This question represents Phase IV of psychotherapy research. It combines the benefits of randomized controlled and naturalistic research. The study is genuinely designed to promote faster and more widespread dissemination of effective interventions. It will answer the questions whether manualized STPP can be implemented into routine outpatient care, whether the new methods improve treatment courses and outcomes and whether treatment effects reached in routine psychotherapeutic treatments are comparable to those of the controlled, strictly manualized treatment of the main study.</p> <p>Trial Registration</p> <p>German Clinical Trials Register (DRKS) DRKS00000570</p

    The German Young Olympic Athletes' Lifestyle and Health Management Study (GOAL Study): design of a mixed-method study

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    <p>Abstract</p> <p>Background</p> <p>In order to perform at top levels, elite athletes have to both protect and risk their health at the same time. Adolescent elite athletes have the additional challenge of coping with substantial physical, psychological and social transformations. The contradictory phenomenon of protecting and risking the adolescent athletes' health in sports challenges the development of health promotion and protection strategies. The GOAL Study (German Young Olympic Athletes' Lifestyle and Health Management Study) analyzes the individual and organizational management of health in adolescent elite sports.</p> <p>Methods/design</p> <p>We combine quantitative and qualitative approaches in a mixed-method study. This allows us to gather a broad range of representative information on squad athletes from all Olympic disciplines as well as in-depth information on four selected Olympic disciplines (artistic gymnastics, biathlon, handball and wrestling). Within the quantitative section we attempt to identify the young athletes' health and nutrition behavior, their subjective health state and their lay health representations, health-related social networks, and structures of medical attendance. 1138 national team level athletes born between 1992 and 1995 from 51 Olympic disciplines responded to the questionnaire (response rate: 61,75%). The qualitative section investigates the meaning and relevance of health and nutrition within the athletes' sports specific surroundings, the impact of biographic backgrounds on individual health behavior, and sports specific cultures of health, nutrition and risk. We interviewed 24 athletes and 28 coaching and medical experts, and carried out 14 multi-day participant observations at training sessions and competitions.</p> <p>Conclusions</p> <p>The studies' results will serve as the basis for developing tailored health promotion strategies to be in cooperation with German elite sports associations.</p
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