23 research outputs found

    Optical repetition MIMO transmission with multipulse PPM

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    Analysis of COVID-19 Guideline Quality and Change of Recommendations: A Systematic Review.

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    Background Hundreds of coronavirus disease 2019 (COVID-19) clinical practice guidelines (CPGs) and expert consensus statements have been developed and published since the outbreak of the epidemic. However, these CPGs are of widely variable quality. So, this review is aimed at systematically evaluating the methodological and reporting qualities of COVID-19 CPGs, exploring factors that may influence their quality, and analyzing the change of recommendations in CPGs with evidence published. Methods We searched five electronic databases and five websites from 1 January to 31 December 2020 to retrieve all COVID-19 CPGs. The assessment of the methodological and reporting qualities of CPGs was performed using the AGREE II instrument and RIGHT checklist. Recommendations and evidence used to make recommendations in the CPGs regarding some treatments for COVID-19 (remdesivir, glucocorticoids, hydroxychloroquine/chloroquine, interferon, and lopinavir-ritonavir) were also systematically assessed. And the statistical inference was performed to identify factors associated with the quality of CPGs. Results We included a total of 92 COVID-19 CPGs developed by 19 countries. Overall, the RIGHT checklist reporting rate of COVID-19 CPGs was 33.0%, and the AGREE II domain score was 30.4%. The overall methodological and reporting qualities of COVID-19 CPGs gradually improved during the year 2020. Factors associated with high methodological and reporting qualities included the evidence-based development process, management of conflicts of interest, and use of established rating systems to assess the quality of evidence and strength of recommendations. The recommendations of only seven (7.6%) CPGs were informed by a systematic review of evidence, and these seven CPGs have relatively high methodological and reporting qualities, in which six of them fully meet the Institute of Medicine (IOM) criteria of guidelines. Besides, a rapid advice CPG developed by the World Health Organization (WHO) of the seven CPGs got the highest overall scores in methodological (72.8%) and reporting qualities (83.8%). Many CPGs covered the same clinical questions (it refers to the clinical questions on the effectiveness of treatments of remdesivir, glucocorticoids, hydroxychloroquine/chloroquine, interferon, and lopinavir-ritonavir in COVID-19 patients) and were published by different countries or organizations. Although randomized controlled trials and systematic reviews on the effectiveness of treatments of remdesivir, glucocorticoids, hydroxychloroquine/chloroquine, interferon, and lopinavir-ritonavir for patients with COVID-19 have been published, the recommendations on those treatments still varied greatly across COVID-19 CPGs published in different countries or regions, which may suggest that the CPGs do not make sufficient use of the latest evidence. Conclusions Both the methodological and reporting qualities of COVID-19 CPGs increased over time, but there is still room for further improvement. The lack of effective use of available evidence and management of conflicts of interest were the main reasons for the low quality of the CPGs. The use of formal rating systems for the quality of evidence and strength of recommendations may help to improve the quality of CPGs in the context of the COVID-19 pandemic. During the pandemic, we suggest developing a living guideline of which recommendations are supported by a systematic review for it can facilitate the timely translation of the latest research findings to clinical practice. We also suggest that CPG developers should register the guidelines in a registration platform at the beginning for it can reduce duplication development of guidelines on the same clinical question, increase the transparency of the development process, and promote cooperation among guideline developers all over the world. Since the International Practice Guideline Registry Platform has been created, developers could register guidelines prospectively and internationally on this platform

    What Influences Chinese Consumers’ Adoption of Battery Electric Vehicles? A Preliminary Study Based on Factor Analysis

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    The rapid development of automobile industry in China did improve people’s quality of life. However, it has also damaged the ecological environment. The emission of a large amount of automobiles is one of the serious air pollution sources. In recent years, the shortage of petrochemical energy, the rapid rise of harmful particles in the air (e.g., PM2.5 and PM10), and the increasing worse atmospheric environment are becoming obstacles to China’s sustainable development. Battery electric vehicles (BEVs) are recognized as an ideal alternative to conventional cars. This study aims to explore the factors that can promote consumers’ adoption of BEVs and to construct domains of these factors. Firstly, an open web questionnaire and semi-structured interviews were conducted to widely collect factors that promote consumers’ purchase of BEVs. Then, questionnaire survey and exploratory factor analysis were used to construct domains of promoting consumers’ purchasing willingness. A total of six factors that promote consumers’ adoption of BEVs were obtained. Finally, the research results can provide references for the Chinese government and the BEV manufacturers in the development and promotion of EVs

    Graphitic carbon nitride as a distinct solid stabilizer for emulsion polymerization

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    g‐C3N4 has been found to be highly functional in many fields, such as photocatalysis, electrocatalysis, and chemical analysis. Pickering emulsion polymerization is a fascinating strategy to fabricate a range of nanomaterials, in which the emulsion is stabilized by solid particles, rather than molecular surfactants. Herein, we demonstrate that g‐C3N4 can act as a remarkable stabilizer for Pickering emulsion polymerization. Contrary to normal Pickering systems, monodisperse polystyrene microspheres with tunable size, surface charge, and morphology were achieved using this approach. Importantly, the g‐C3N4 hybridized latex is highly processable and has exhibited multiple functions: manufacture of photonic crystals via self‐organization, stabilizing Pickering emulsion owing to proper wettability, and acting as bioimaging agents with enriched fluorescent colors. Considering the easy synthesis and low cost of g‐C3N4, our approach has a high potential for scale‐up synthesis and practical translation

    Cellular uptake of nickel by NikR is regulated by phase separation

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    Summary: Bacterial cells were long thought to be “bags of enzymes” with minimal internal structures. In recent years, membrane-less organelles formed by liquid-liquid phase separation (LLPS) of proteins or nucleic acids have been found to be involved in many important biological processes, although most of them were studied on eukaryotic cells. Here, we report that NikR, a bacterial nickel-responsive regulatory protein, exhibits LLPS both in solution and inside cells. Analyses of cellular nickel uptake and cell growth of E. coli confirm that LLPS enhances the regulatory function of NikR, while disruption of LLPS in cells promotes the expression of nickel transporter (nik) genes, which are negatively regulated by NikR. Mechanistic study shows that Ni(II) ions induces the accumulation of nik promoter DNA into the condensates formed by NikR. This result suggests that the formation of membrane-less compartments can be a regulatory mechanism of metal transporter proteins in bacterial cells

    Self-Assembly of Fluorescent Organic Nanoparticles for Iron(III) Sensing and Cellular Imaging

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    Fluorescent organic nanoparticles have attracted increasing attentions for chemical or biological sensing and imaging due to their low-toxicity, facile fabrication and surface functionalization. In this work, we report novel fluorescent organic nanoparticles via facile self-assembly method in aqueous solution. First, the designed water-soluble fluorophore shows a weak and negligible intrinsic fluorescence in water. Upon binding with adenosine-5′-triphosphate (ATP), fluorescent nanoparticles were formed immediately with strongly enhanced fluorescence. These fluorescent nanoparticles exhibit high sensitivity and selectivity toward Fe<sup>3+</sup> sensing with detection limit of 0.1 nM. In addition, after incubation with HeLa cells, the fluorophore shows excellent imaging performance by interaction with entogenous ATP in cells. Finally, this fluorescent system is also demonstrated to be capable of Fe<sup>3+</sup> sensing via fluorescence quenching in cellular environment

    Ultrabright Fluorescent Silica Nanoparticles Embedded with Conjugated Oligomers and Their Application in Latent Fingerprint Detection

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    Fluorescent micro- and nanosized particles have a broad range of applications in biology, medicine, and engineering. For these uses, the materials should have high emission efficiency and good photostability. However, many organic fluorophores suffer from aggregation-induced quenching effects and photobleaching. Here, we used a simple method based on covalently blending a fluorescent conjugated oligomer with silica nanoparticles to achieve emission quantum yields as high as 97%. The resulting system also showed excellent stability under continuous light illumination, in a range of pH values and temperatures, and in common solvents. This fluorescent material showed outstanding properties, including highly efficient blue emission, low cost, low toxicity, and easy synthesis. Furthermore, its effectiveness for latent fingerprint detection was demonstrated as a proof of concept on various substrates. The obtained emissive fingerprint powder gave good optical/fluorescent images with high contrast and resolution between the ridges and spaces
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