52 research outputs found

    Using protection motivation theory to explain the intention to initiate human papillomavirus vaccination among men who have sex with men in China

    Get PDF
    Human papillomavirus (HPV) infection and related diseases are common among men who have sex with men (MSM). The most effective prevention is HPV vaccination. In China, however, men are not included in the HPV vaccination plan. We investigated the intention to initiate HPV vaccination and associated factors among MSM in China. Methods We surveyed 563 unvaccinated MSM aged 18 or older from six cities in China. Participants completed an electronic questionnaire about demographics, knowledge of and attitude towards HPV and HPV vaccine, intention to initiate HPV vaccination, willingness to recommend HPV vaccine to peers, feeling about government policy about HPV vaccination. We used the structural equation modeling (SEM) to analyze factors associated with HPV vaccine intention. Results The knowledge of HPV and HPV vaccine among participants was low. The mean score of knowledge about HPV and HPV vaccine was only 1.59 (range 0–11). The intention to initiate HPV vaccination within 6 months among participants was moderate (43.3% in total, 18.1% for ‘very high' and 25.2% for ‘above average')

    Causal association between serum 25-Hydroxyvitamin D levels and cutaneous melanoma: a two-sample Mendelian randomization study

    Get PDF
    BackgroundDespite numerous observational studies on the association between serum 25-Hydroxyvitamin D levels and cutaneous melanoma, causal inferences remain ambiguous due to confounding and reverse causality. This study aimed to elucidate the causal relationship between serum 25-Hydroxyvitamin D levels and melanoma incidence using Mendelian randomization (MR).MethodsA two-sample MR was conducted using genetic variants associated with serum 25-Hydroxyvitamin D levels as instrumental variables. Summary statistics for these variants were derived from genome-wide association studies, and those for melanoma risk were obtained from a comprehensive melanoma case-control study. Robustness of the results was assessed through sensitivity analyses, including the “leave-one-out” approach and tests for potential pleiotropy.ResultsThe MR analysis provided substantial evidence of a positive causal relationship between serum 25-Hydroxyvitamin D levels and the incidence of cutaneous melanoma, suggesting that each unit increase in serum 25-Hydroxyvitamin D levels corresponds with an increased risk of melanoma. Tests for pleiotropy showed minimal effects, and the sensitivity analysis confirmed no disproportionate influence by any individual single nucleotide polymorphism (SNP).ConclusionThe findings indicated a potentially causal positive association between serum 25-Hydroxyvitamin D levels and melanoma risk, challenging traditional beliefs about vitamin D’s role in melanoma. This emphasizes the need for a balanced and personalized approach to vitamin D supplementation and sun exposure, particularly in high-risk populations. These results should be interpreted with caution due to potential unrecognized pleiotropy and confounding factors. Future research should focus on validating these findings in diverse populations and exploring underlying biological mechanisms

    Contextualizing the Revised Patient Perception of Patient-Centeredness (Pppc-R) Scale in Primary Healthcare Settings: a Validity and Reliability Evaluation Study

    Get PDF
    BACKGROUND: An English version of the Patient Perception of Patient-Centeredness (PPPC) scale was recently revised, and it is necessary to test this instrument in different primary care populations. AIM: This study aimed to assess the validity and reliability of a Chinese version of the PPPC scale. DESIGN: A mixed method was used in this study. The Delphi method was used to collect qualitative and quantitative data to address the content validity of the PPPC scale by calculating the Content Validity Index, Content Validity Ratio, the adjusted Kappa, and the Item Impact Score. Confirmatory factor analysis (CFA) and exploratory factor analysis (EFA) were used to assess the construct validity of the PPPC scale through a cross-sectional survey. The internal consistency was also assessed. SETTING/PARTICIPANTS: In the Delphi consultation, seven experts were consulted through a questionnaire sent by email. The cross-sectional survey interviewed 188 outpatients in Guangzhou city and 108 outpatients in Hohhot City from community health service centers or stations face-to-face. RESULTS: The 21 items in the scale were relevant to their component. The Item-level Content Validity Index for each item was higher than 0.79, and the average Scale-level content validity index was 0.97 in each evaluation round. The initial proposed 4-factor CFA model did not fit adequately. Still, we found a 3-factor solution based on our EFA model and the validation via the CFA model (model fit: [Formula: see text], P \u3c 0.001, RMSEA = 0.044, CFI = 0.981; factor loadings: 0.553 to 0.888). Cronbach\u27s α also indicated good internal consistency reliability: The overall Cronbach\u27s α was 0.922, and the Cronbach\u27s α for each factor was 0.851, 0.872, and 0.717, respectively. CONCLUSIONS: The Chinese version of the PPPC scale provides a valuable tool for evaluating patient-centered medical service quality

    Robust estimation of bacterial cell count from optical density

    Get PDF
    Optical density (OD) is widely used to estimate the density of cells in liquid culture, but cannot be compared between instruments without a standardized calibration protocol and is challenging to relate to actual cell count. We address this with an interlaboratory study comparing three simple, low-cost, and highly accessible OD calibration protocols across 244 laboratories, applied to eight strains of constitutive GFP-expressing E. coli. Based on our results, we recommend calibrating OD to estimated cell count using serial dilution of silica microspheres, which produces highly precise calibration (95.5% of residuals <1.2-fold), is easily assessed for quality control, also assesses instrument effective linear range, and can be combined with fluorescence calibration to obtain units of Molecules of Equivalent Fluorescein (MEFL) per cell, allowing direct comparison and data fusion with flow cytometry measurements: in our study, fluorescence per cell measurements showed only a 1.07-fold mean difference between plate reader and flow cytometry data

    Performance, Design

    No full text
    In an indoor ultra-wideband (UWB) communication environment, the line-of-sight (LOS) between the transmitter and receiver may be frequently blocked by moving people. Blocking of LOS may significantly affect the quality of service (QoS) of on-going UWB communications. Based on the Angular Power Spectrum and the human blocking models, we build a packet-level UWB channel model considering the shadowing processes. The model is simple enough to be incorporated into existing network simulators and it can be used to facilitate protocol design and QoS analysis for UWB based wireless personal area networks (WPANs)

    Joint AMC and Packet Fragmentation for Error Control Over Fading Channels

    No full text

    Resource management for multimedia services in high data rate wireless networks

    No full text
    This brief offers a valuable resource on principles of quality-of-service (QoS) provisioning and the related link-layer resource management techniques for high data-rate wireless networks. The primary emphasis is on protocol modeling and analysis. It introduces media access control (MAC) protocols, standards of wireless local area networks (WLANs), wireless personal area networks (WPANs), and wireless body area networks (WBANs), discussing their key technologies, applications, and deployment scenarios. The main analytical approaches and models for performance analysis of the fundamental resource scheduling mechanisms, including the contention-based, reservation-based, and hybrid MAC, are presented. To help readers understand and evaluate system performance, the brief contains a range of simulation results. In addition, a thorough bibliography provides an additional tool. This brief is an essential resource for engineers, researchers, students, and users of wireless networks

    Research on the generating mechanism among dominant scientific relationships of international cooperation based on GERGM

    No full text
    <p>This article uses the 235,746 papers published in the field of artificial intelligence from 2001-2020 to quantify dominant scientific relationships based on international collaboration. The analysis of these relationships of international cooperation was systematically explored by referring to both endogenous and exogenous effects. After the generalized exponential random graph model was applied, results were obtained which show that:</p> <p>①There is a strong tendency for countries to develop mutually-led international scientific collaborations with established partners;</p> <p>②Scientific productivity and the R&D expenditure play a crucial role in countries generating dominant scientific relationships based on international scientific cooperation, which is also significant for countries who seek to form dominant relationships;</p> <p>③Geographical distance is still a major constraint on generating international scientific ties between two countries. Countries that share the same official language have a strong tendency to form new collaborations. This paper reveals the role of endogenous structural factors based on edge dependencies and considers their impact on dominant international scientific collaborations. We introduce GERGM to scientometrics, which has been applied to avoid information being lost in traditional binary network simulations.</p&gt
    corecore