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Aiming at the problem that the Beidou B1I navi¬gation receiver is susceptible to continuous-wave interfer¬ence (CWI), it is of great significance to investigate the interference effect and mechanism of the B1I navigation receiver. With the threshold of carrier-to-noise ratio (C/N0) as the criterion of satellite tracking missing, the CWI injection experiment is conducted on a kind of B1I navigation receiver. The results indicate that the power spectrum of the satellite signal affects the CWI's ability to interfere with each satellite. Then, a prediction model of satellite tracking loss under dual-frequency CWI is proposed, and the accuracy of the model is verified through experiments. The experiment results demonstrate that the power combination between the dual-frequency CWI is negatively correlated, and the error of this model is less than 2 dB. Finally, the sensitive frequency bands of the navigation receiver under out-of-band CWI are obtained through experiments. It is confirmed by theoretical and simulation analysis that the mixer is the main non-linear circuit generating these sensitive frequency bands. Furthermore, improving the selectivity of the radio frequency (RF) front-end circuit can enhance the performance of anti out-of-band interference.

Abstract Background Transient ischemic attack (TIA) patients are at high risk of recurrent vascular events; timely management can reduce that risk by 70%. The Protocol-guided Rapid Evaluation of Veterans Experiencing New Transient Neurological Symptoms (PREVENT) developed, implemented, and evaluated a TIA quality improvement (QI) intervention aligned with Learning Healthcare System principles. Methods This stepped-wedge trial developed, implemented and evaluated a provider-facing, multi-component intervention to improve TIA care at six facilities. The unit of analysis was the medical center. The intervention was developed based on benchmarking data, staff interviews, literature, and electronic quality measures and included: performance data, clinical protocols, professional education, electronic health record tools, and QI support. The effectiveness outcome was the without-fail rate: the proportion of patients who receive all processes of care for which they are eligible among seven processes. The implementation outcomes were the number of implementation activities completed and final team organization level. The intervention effects on the without-fail rate were analyzed using generalized mixed-effects models with multilevel hierarchical random effects. Mixed methods were used to assess implementation, user satisfaction, and sustainability. Discussion PREVENT advanced three aspects of a Learning Healthcare System. Learning from Data: teams examined and interacted with their performance data to explore hypotheses, plan QI activities, and evaluate change over time. Learning from Each Other: Teams participated in monthly virtual collaborative calls. Sharing Best Practices: Teams shared tools and best practices. The approach used to design and implement PREVENT may be generalizable to other clinical conditions where time-sensitive care spans clinical settings and medical disciplines. Trial registration clinicaltrials.gov: NCT02769338 [May 11, 2016].

At present, Fiber metal laminates (FMLs) are mostly used in the aeronautical field to manufacture large-size components, such as skins of fuselage or wing. However, the utilization of FMLs in microsystems and micro-electro-mechanical systems has not been explored yet. Therefore, miniaturization of conventional FMLs and integration of micro-sheet preparation and complex-shaped components forming are of utmost significance from a practical viewpoint. Herein, an integrated ultrasonic-assisted preparation-forming-curing method is proposed to manufacture ultra-thin micro-Ti/Cf/PPS hybrid laminates (TA1/Carbon fiber/PPS) components in this paper. The influence of ultrasonic vibrations on the performance of as-prepared micro-laminates is systematically studied, including the immersion distribution of PPS resin in Cf layer, interfacial bonding properties of Cf/PPS and Ti/PPS interfaces and micro-deformation mechanism of metallic layer. Furthermore, the hot bulging test is carried out by rapid transfer of the micro-laminates at melting temperature (280 °C) of the resin layer using a micro-arrayed spherical-cap die to assess the formability. A combination of electron backscatter diffraction (EBSD) analysis, metallographic observations and image precision measurement revealed the unique deformation characteristics and thickness evolution of complex-shaped micro-Ti/Cf/PPS laminates. Overall, a high deformation level is achieved during the bulging process. The current study provides an enhanced understanding of ultrasonic-assisted micro-forming-curing process.

Abstract Otolaryngologists frequently serve as the first touchpoint for patients presenting with dermatologic conditions of the head and neck. This study aims to identify and quantify gaps in dermatologic training among otolaryngology residents, and to assess their diagnostic accuracy in comparison to dermatology residents. It comprised 14 multiple‐choice questions focused on common dermatologic diagnoses related to the head and neck. Sixty‐one dermatology and 36 otolaryngology residents participated in the study. Dermatology residents significantly outperformed otolaryngology residents, with average scores of 90% (SD = 8) compared to 71% (SD = 10) (P

Confirmation biases make consumers feel comfortable because consistent beliefs simplify the processing of electronic word-of-mouth (eWOM). Whether the helpfulness of eWOM is a belief of information underlying biased information, i.e., positive–negative asymmetry, or an illusion of overconfidence underlying biased judgment, i.e., belief consistency, is crucial to the foundation of theory and the advance of practice in user-generated persuasion. The questions challenge the literature that the helpfulness of product reviews relies on unbiased information and/or unbiased judgment. Drawing on the cognitive-information lens, we developed a research model to explain how belief consistency affects the helpfulness beliefs of eWOM, and examined the effects of positive–negative asymmetry. Using a scenario-based questionnaire survey, we collected 334 consumer samples to test the research model. According to the empirical results, the conflicts of influence between positive and negative confirmation indicated that perceived review helpfulness was a belief of information and constrained by the positive–negative review frame. Without using personal expertise, respondents’ consistent beliefs were significant to confirm positive reviews as useful and thereby perceive the review content as helpful, which is an illusion of overconfidence and constrained by belief consistency. Whether personal expertise reinforces the effect of belief consistency depends on the positive–negative asymmetry.