2,066 research outputs found

    Research on optimization-based design

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    Research on optimization-based design is discussed. Illustrative examples are given for cases involving continuous optimization with discrete variables and optimization with tolerances. Approximation of computationally expensive and noisy functions, electromechanical actuator/control system design using decomposition and application of knowledge-based systems and optimization for the design of a valve anti-cavitation device are among the topics covered

    Healing Thyself: What Barriers Do Psychologists Face When Considering Personal Psychotherapy and How Can They Be Overcome?

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    Most mental health professionals seek personal psychotherapy at least once in their careers (Phillips, 2011), and at a much higher rate than the general population (Norcross & Guy, 2005). While one-fourth of the general adult population has received mental health services, three-fourths of mental health professionals have done so (Bike, Norcross, & Schatz, 2009; Norcross & Guy, 2005). A wealth of studies have explored why psychologists have sought personal psychotherapy — often for the same reason that the rest of the world seeks therapy, such as coping with loss, dealing with depression or anxiety, or struggling with a personal crisis. However, more research is needed about the potential barriers that psychologists may experience when considering such treatment. In this article, we discuss the research exploring why psychologists may benefit from psychotherapy and report on the findings of our own national survey, which explored independent practitioners\u27 perceived barriers to psychological care

    Millimeter Wave Substrate Integrated Waveguide Antennas: Design and Fabrication Analysis

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    The paper presents a new concept in antenna design, whereby a photo-imageable thick-film process is used to integrate a waveguide antenna within a multilayer structure. This has yielded a very compact, high performance antenna working at high millimeter-wave (mm-wave) frequencies, with a high degree of repeatability and reliability in antenna construction. Theoretical and experimental results for 70 GHz mm-wave integrated antennas, fabricated using the new technique are presented. The antennas were formed from miniature slotted waveguide arrays using up to 18 layers of photo-imageable material. To enhance the electrical performance a novel folded waveguide array was also investigated. The fabrication process is analysed in detail and the critical issues involved in the fabrication cycle are discussed. The losses in the substrate integrated waveguide have been calculated. The performance of the new integrated antenna is compared to conventional metallic, air-filled waveguide antennas, and also to conventional microstrip antenna arrays operating at the same frequencies

    Queen discrimination by honeybee (Apis mellifera L) workers

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    A simple new technique for testing worker honeybees' ability to distinguish between honeybee queens is presented. Two queens were caged separately with groups of young sibling workers which were the daughters of another queen. The cages were exposed to the same environmental odours for 10 days. When placed in the test apparatus and given a choice of both queens, workers segregated towards the queen with which they had been caged. This provides further evidence that the distinctive odour of an individual queen is probably partly inherited and is learned by workers. The nature and functioning of queen odours are discussed

    Strategies Employed by Clergy to Prevent and Cope with Interpersonal Isolation

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    Numerous studies have affirmed that interpersonal isolation is one of the unique challenges clergy face. This study examined the experience of interpersonal isolation among a sample of clergy serving in a senior pastor role by having them complete a modified form of the Social Support Questionnaire, Short Form (SSQSR), as well as six open-ended interview questions. The interview responses of clergy participants were compared based on a median split of the SSQSR satisfaction scores. Analysis of clergy responses revealed several prominent themes in the following areas: barriers to establishing supportive relationships, strategies for establishing and maintaining supportive relationships, lack of support, and coping with loneliness. Identified themes, as well as clergy responses that exemplified these themes, are discussed. Clergy with social support scores at or above the median more frequently indicated that being transparent and vulnerable is a means by which they establish and maintain close, supportive relationships with others

    Barriers to Psychologists Seeking Mental Health Care

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    Professional psychologists provide help to people in need, but how freely do psychologists seek psychotherapy themselves when facing personal challenges and struggles? What obstacles make it difficult for professional psychologists to seek psychotherapy? A survey of 260 professional psychologists (52% response rate) was conducted to investigate the frequency of various stressors impacting professional psychologists and the barriers they experience in seeking mental health services. Though none of the stressors were rated with particularly high frequencies, burnout was identified as the most frequent problem. Difficulty finding a psychotherapist and a lack of time were identified as the greatest obstacles to seeking psychotherapy. Practice and training implications are discussed as well as future research directions

    Nicotinic Receptor Interloop Proline Anchors β1-β2 and Cys loops in Coupling Agonist Binding to Channel Gating

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    Nicotinic acetylcholine receptors (AChRs) mediate rapid excitatory synaptic transmission throughout the peripheral and central nervous systems. They transduce binding of nerve-released ACh into opening of an intrinsic channel, yet the structural basis underlying transduction is not fully understood. Previous studies revealed a principal transduction pathway in which αArg 209 of the pre-M1 domain and αGlu 45 of the β1–β2 loop functionally link the two regions, positioning αVal 46 of the β1–β2 loop in a cavity formed by αPro 272 through αSer 269 of the M2–M3 loop. Here we investigate contributions of residues within and proximal to this pathway using single-channel kinetic analysis, site-directed mutagenesis, and thermodynamic mutant cycle analysis. We find that in contributing to channel gating, αVal 46 and αVal 132 of the signature Cys loop couple energetically to αPro 272. Furthermore, these residues are optimized in both their size and hydrophobicity to mediate rapid and efficient channel gating, suggesting naturally occurring substitutions at these positions enable a diverse range of gating rate constants among the Cys-loop receptor superfamily. The overall results indicate that αPro 272 functionally couples to flanking Val residues extending from the β1–β2 and Cys loops within the ACh binding to channel opening transduction pathway
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