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The outbreak of COVID-19 makes people feel distant from each other, and masks have become one of the indispensable articles in People's Daily life. At present, there are many brands of masks with various types and uneven quality. In order to understand the current market of masks and the sales of different brands, users can choose masks with perfect quality. This paper uses Python web crawler technology, based on the input of the word "mask", crawl JD website sales data, through data visualization technology drawing histogram, pie chart, the word cloud, etc., for goods compared with the relationship between price, average price of all brands, brands, average distribution of analysis and evaluation of user information, In this way, the sales situation, price distribution and quality evaluation of each store of the product can be visually displayed. At the same time, it also provides some reference for other users who need to buy the product. © The Authors. Published under a Creative Commons Attribution CC-BY 3.0 License.
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Based on signal amplification strategy of dendritic mesoporous silica nanospheres loaded with CdSe/ZnS quantum dots (DMSN@QDs), an ultrasensitive electrochemiluminescence (ECL) immunosensor with magnetic separation was constructed for the detection of SARS-CoV-2 nucleocapsid protein (NP). DMSN, a mesoporous material with abundant radial pores, large specific surface area and high porosity, can increase the loading capacity of QDs and hinder their aggregation as the nanocarrier. DMSN@QDs with good ECL efficiency were used as signal labels to construct a sandwich immunosensor. The designed ECL immunosensor displayed a good linear relationship for NP concentrations ranging from 0.005 ng mL(-1) to 50 ng mL(-1), with a limit of detection of 3.33 pg mL(-1). The ECL immunosensor was successfully applied to detect NP in human serum samples with satisfactory recovery. This strategy provided a new method for detecting NP and expanded the application field of DMSN.
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Over the past two years, China has wrested domestic control of the COVID-19 pandemic through non-pharmaceutical interventions. However, the extent to which the pandemic has changed people's travel behavior in the new normal under the zero-COVID policy is not yet clear. This study investigates the profound effects of the zero-COVID strategy on human mobility in 365 Chinese cities over time. Our results suggest the following: (1) Even between city pairs with no local cases, intercity mobility decreased by an average of 16%, whereas intra-city mobility increased by 9% compared with the pre-pandemic baseline. Long-distance travel decreased substantially, while trips below 100 km increased slightly. These new trends indicate a localized pattern which is presumably caused by the wide adoption of teleworking and virtual classes, as well as concerns about the safety and availability of public transportation. (2) Containment measures caused a considerably acute decline in intercity short-distance trips but exerted a markedly lasting effect on long-distance trips. (3) Cities with lower levels of urbanization, smaller population sizes, less labor force, and lower GDP and GDP per capita experienced greater reductions in mobility, which may be due to their insufficient management capabilities. (4) The Chinese government has adopted adaptive measures to contain outbreaks. Stricter and more timely responses led to faster recoveries in the second half of 2021 compared with the first half. Inter- and intra-city mobility decreased by 41% and 26%, respectively, within the first 2 weeks of an outbreak, and it took 6-7 weeks to return to pre-outbreak levels. © The Author(s) 2023.
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Blood vessel chips are bioengineered microdevices, consisting of biomaterials, human cells, and microstructures, which recapitulate essential vascular structure and physiology and allow a well-controlled microenvironment and spatial-temporal readouts. Blood vessel chips afford promising opportunities to understand molecular and cellular mechanisms underlying a range of vascular diseases. The physiological relevance is key to these blood vessel chips that rely on bioinspired strategies and bioengineering approaches to translate vascular physiology into artificial units. Here, several critical aspects of vascular physiology are discussed, including morphology, material composition, mechanical properties, flow dynamics, and mass transport, which provide essential guidelines and a valuable source of bioinspiration for the rational design of blood vessel chips. The state-of-art blood vessel chips are also reviewed that exhibit important physiological features of the vessel and reveal crucial insights into the biological processes and disease pathogenesis, including rare diseases, with notable implications for drug screening and clinical trials. It is envisioned that the advances in biomaterials, biofabrication, and stem cells improve the physiological relevance of blood vessel chips, which, along with the close collaborations between clinicians and bioengineers, enable their widespread utility. © 2023 Wiley-VCH GmbH.
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The deterioration of environmental quality has attracted the attention of the Chinese government and the public. The Chinese government has delegated part of the power of environmental regulation to local governments. To fulfill the KPI, local governments tend to loosen environmental regulations to attract more settlement of enterprises, thus leading to an increasingly fierce local environmental regulation competition. The improvement of people’s living standards makes it possible for the public to participate in environmental regulation. This article seeks to carry out the empirical study to interpret the relationship between local environmental regulation competition, public participation, and enterprise location selection through a random effects (RE) spatial Durbin model with 29 provincial panel data in China from 2004 to 2017. The results show that the provincial spatial spillover effect of enterprise location selection is significant. More intensified local environmental regulation competition can attract more investment but may harm sustainable economic development. Active public participation can effectively avoid the excessive investment caused by local environmental regulation competition and sustain economic development. Therefore, we should establish and improve the local environmental prevention and regulation system and establish an information disclosure mechanism to ensure public participation. The local government’s environmental regulation and public participation mechanism should be effectively coordinated. Copyright © 2022 Mu, Zhan, Ameer, Anser, Zeng and Amin.
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As an important symbol and carrier of regional social and economic activities, population mobility is a vital force to promote the re-agglomeration and diffusion of social and economic factors. An accurate and timely grasp on the impact of the COVID-19 epidemic on population mobility between cities is of great significance for promoting epidemic prevention and control and economic and social development. This study proposes a theoretical framework for resilience assessment, using centrality and nodality, hierarchy and matching, cluster, transmission, and diversity to measure the impact of the COVID-19 epidemic on population mobility in the Beijing-Tianjin-Hebei (BTH) urban agglomeration in 2020-2022, based on the migration data of AutoNavi and social network analysis. The results show that the COVID-19 epidemic had different impacts on the population network resilience of the BTH urban agglomeration based on the scale and timing. During the full-scale outbreak of the epidemic, strict epidemic prevention and control measures were introduced. The measures, such as social distancing and city and road closure, significantly reduced population mobility in the BTH urban agglomeration, and population mobility between cities decreased sharply. The population mobility network's cluster, transmission, and diversity decreased significantly, severely testing the network resilience. Due to the refinement of the epidemic control measures over time, when a single urban node was impacted, the urban node did not completely fail, and consequently it had little impact on the overall cluster, transmission, and diversity of the population mobility network. Urban nodes at different levels of the population mobility network were not equally affected by the COVID-19 epidemic. The findings can make references for the coordination of epidemic control measures and urban development. It also provides a new perspective for the study of network resilience, and provides scientific data support and a theoretical basis for improving the resilience of BTH urban agglomeration and promoting collaborative development.
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With the rapid spread and proliferation of Coronavirus disease 2019 (COVID-19) worldwide, highly pathogenic severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) seriously threatens human life and health. The rapid and accurate abilities to detect SARS-CoV-2 have become the key to prevent and control COVID-19. Electrochemical sensors have shown broad application prospects in biological detection because of the advantages of high sensitivity, specificity, and short time-consuming. This review summarizes the application of electrochemical biosensors in detecting SARS-CoV-2 and discusses prospects for developing direction in this field.
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Biosafety is an important guarantee of the new coronavirus laboratory test. The accident treatment of sample overflow and sprinkle is a necessary part of the emergency plan for testing activities. Beijing Preventive Medicine Association coordinated biosafety experts of COVID-19 laboratories from Beijing CDC, to write up "The standard for handling of accidents of corona virus disease 2019 sample (T/BPMA 0005-2020)" . The group standard was based on the guidelines of China and WHO, and combined with the practical experience of COVID-19 epidemic and the principle of "scientific, normative, applicable and feasible" . Through all kinds of risk Assessment, it included the spillover of samples caused by the packing of COVID-19 (highly pathogenic) samples, the overflow and sprinkle in the laboratory during the detection operation, and the spillage accident occurred during the transfer of samples in the same building. The standard could guide and standardize the handling methods of accidental overflow and sprinkle that may occur in the SARS-CoV-2 testing laboratories in the city.
Subject(s)
Biohazard Release , Clinical Laboratory Techniques , Containment of Biohazards/standards , Beijing , COVID-19 Testing , Coronavirus Infections/diagnosis , HumansABSTRACT
AIM: To provide suggestion for research and development of drugs against coronavirus disease 2019 (COVID-19) by analyzing the characteristics of the drug clinical trial registration information of COVID-19 in China. METHODS: The clinical trials of COVID-19 were searched from Chinese Clinical Trial Registry, and the type, purpose, and design of the studies were analyzed. RESULTS: Totally 271 drug clinical trials have been registered till July 1st, 2020. Most of the drugs are marketed ones, including chemical drugs, traditional Chinese medicines, and biologics. Combined applications were adopted in some projects. Randomized or non-randomized parallel control trials were conducted in most projects. Others included single arm, sequential, and factorial design. CONCLUSION: To deal with the epidemic, it is important to conduct emergent drug clinical trials to find out effective drugs as soon as possible. However, some weaknesses and deficiencies on trials design, conduct and supervision were exposed in the drug clinical trials against COVID-19. It is suggested to enhance the scientific evaluation of candidate drugs, standardize the investigator initiated trials, and establish the national multi-subject research and development platform, and the collaborative and innovative key-task tackling mechanism, thus to improve the ability and level of antiviral drug research and development.
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Objective: To summarize and analyze the clinical and imaging characteristics of patients with 2019 novel coronavirus pneumonia in the early stage in Beijing. Methods: A retrospective analysis of clinical and imaging data of 9 patients with 2019 novel coronavirus infection diagnosed in one fever clinicic in Beijing from January 18, 2020 to February 3, 2020. Results: 5 male and 4 female was included in those 9 patients, whose median age was 36 years, and the age range from 15 to 49 years. 8 of these patients had no underlying disease and one suffered from diabetes. 7 patients had a history of travel to Wuhan City or Hubei Province, and one patient was a medical staff. Two family clustered was found. The incubation period was 1 to 6 days. The clinical manifestations were fever in 8 cases (8/9) , dry cough in 5 cases (5/9) , pharyngalgia in 4 cases (4/9) , fatigue in 4 cases (4/9) , body soreness in 4 cases (4/9) , and blocked or watery nose in 1 case (1/9) . Six patients (6/9) had abnormal cell peripheral blood, of which 3 (3/9) had an increased monocyte count, 2 (2/9) had a reduced lymphocyte , and 1 (1/9) had an increased leukocyte count, while the 3 patients had normal cell blood routines. The median of CRP was 16.3 mg/L, including 5 patients with slightly elevated (5/9) , 4 patients with normal values (4/9) . the results of procalcitonin test were negative in5 patients. Three patients were examined by chest X-ray examination, one of which was normal, one case showed infiltrates of right upper lung, and another showed in right lower lung. All patients underwent chest HRCT. And 7 cases (7/9) showed multiple ground glass exudation, including 5 cases (5/7) involved bilateral lungs, 2 cases (2/7) involved unilateral lung, 3 cases (3/7) with patchy consolidation, and 2 cases (2/9) showed no abnormality. Conclusions: The patents with 2019 novel coronavirus pneumonia in this study generally have an epidemiological history. The clinical manifestations are fever and cough. Peripheral white blood cell counts were most normal And PCT were all negative. Chest HRCT manifested as multiple ground-glass opacities with partly consolidation. Some patients had normal chest radiographs but HRCT showed pneumonia. Some patients had no pneumonia on chest HRCT.