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To assess occupational exposure to electromagnetic fields, 11 microwave (MW), 4 short-wave diathermy and 15 magneto therapy devices were analysed in eight physiotherapy departments. Measurements taken at consoles and environmental mapping showed values above European Directive 2004/40/EC and ACGIH exposure limits at approximately 50 cm from MW applicators (2.45 GHz) and above the Directive magnetic field limit near the diathermy unit (27.12 MHz). Levels in front of MW therapy applicators decreased rapidly with distance and reduction in power; this may not always occur in work environments where nearby metal structures (chairs, couches, etc.) may reflect or perturb electromagnetic fields. Large differences in stray field intensities were found for various MW applicators. Measurements of power density strength around MW electrodes confirmed radiation fields between 30 degrees and 150 degrees , with a peak at 90 degrees , in front of the cylindrical applicator and maximum values between 30 degrees and 150 degrees over the whole range of 180 degrees for the rectangular parabolic applicator. Our results reveal that although most areas show substantially low levels of occupational exposure to electromagnetic fields in physiotherapy units, certain cases of over-occupational exposure limits do exist.  相似文献   
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This paper describes the design, the realization and the experimental characterization of a micromachined band‐pass filter with a working frequency of 38GHz. The synthesis of the structure has been carried out by means of the image parameter representation of two‐port networks. A coupled line coplanar configuration has been adopted for the filtering network. The good agreement between theoretical and experimental results demonstrates the validity of the proposed design approach. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   
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Microsystem Technologies - Triangular resonators, designed by using Radio Frequency Micro Electro Mechanical Systems (RF MEMS) cantilevers in coplanar waveguide (CPW) configuration, have been...  相似文献   
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This research aims at demonstrating that wayfinding solutions can improve the effectiveness of the evacuation processes in complex architectural spaces such as those of cruise ships. We investigated the behaviours of passengers in maritime disaster to figure out whether people act similarly during buildings egress and ships evacuation. Data were collected through questionnaires administered in 2015 to passengers boarding various cruise ships at the port of Ancona (Italy), and through the analysis of real footage of the evacuation of the Costa Concordia. The open source software Fire Dynamics Simulator with Evacuation (FDS+EVAC), used in building egress analyses, was adapted to include these behavioural and event information such as familiarity with ship layout, ship rotation and lifeboats boarding. Simulation results on the case study confirmed similarities between ships and buildings evacuations, underlining the effectiveness of wayfinding solutions to improve passengers’ evacuation flows and routes selection. This study also demonstrated that computer simulation could benefit the ship design process, the preparation of safety guidelines, and the crewmembers during naval emergency management training.  相似文献   
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ABSTRACT. Objective: To investigate the unique contributions of social problem solving abilities and social support in the prediction of aspects of caregiver adjustment. Study Design: Correlational procedures were used to determine the unique contributions of social problem-solving abilities and social support in the prediction of caregiver depression, health, and life satisfaction. Mediating factors were examined with correlational and regression analyses. Participants: Caregivers of individuals who had a stroke (20 African Americans and 20 Caucasians). Main Outcome Measures: The general health scale from the Short-Form Health Survey and measures of life satisfaction and depression. Results: Social support was the best predictor of caregiver life satisfaction. Perceived control over emotions when solving problems was the best predictor of caregiver depressive behavior and health. Social problem-solving abilities were associated with caregiver depressive behavior and health; social support did not mediate these relationships. Conclusions: Problem-solving interventions may be most appropriate for the treatment and prevention of caregiver depression and health problems. Social support programs may be indicated for caregiver life satisfaction. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Persistent infection with High Risk-Human Papilloma Viruses (HR-HPVs) is a primary cause of cervical cancer worldwide. Vaginal-dysbiosis-associated bacteria were correlated with the persistence of HR-HPVs infection and with increased cancer risk. We obtained strains of the most represented bacterial species in vaginal microbiota and evaluated their effects on the survival of cervical epithelial cells and immune homeostasis. The contribution of each species to supporting the antiviral response was also studied. Epithelial cell viability was affected by culture supernatants of most vaginal-dysbiosis bacteria, whereas Lactobacillus gasseri or Lactobacillus jensenii resulted in the best stimulus to induce interferon-γ (IFN-γ) production by human mononuclear cells from peripheral blood (PBMCs). Although vaginal-dysbiosis-associated bacteria induced the IFN-γ production, they were also optimal stimuli to interleukin-17 (IL-17) production. A positive correlation between IL-17 and IFN-γ secretion was observed in cultures of PBMCs with all vaginal-dysbiosis-associated bacteria suggesting that the adaptive immune response induced by these strains is not dominated by TH1 differentiation with reduced availability of IFN-γ, cytokine most effective in supporting virus clearance. Based on these results, we suggest that a vaginal microbiota dominated by lactobacilli, especially by L. gasseri or L. jensenii, may be able to assist immune cells with clearing HPV infection, bypasses the viral escape and restores immune homeostasis.  相似文献   
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The design and testing of a new configuration of micromachined bandpass filter for millimetre-wave applications is presented. The design is based on image parameter representation of identical symmetrical cells connected in cascade. The measurements demonstrate transmission losses lower than 1 dB and very good agreement with the electromagnetic simulations.  相似文献   
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