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1.
Transportation research record ; 2677(4):168-180, 2021.
Artículo en Inglés | EuropePMC | ID: covidwho-2320839

RESUMEN

The research team has utilized privacy-protected mobile device location data, integrated with COVID-19 case data and census population data, to produce a COVID-19 impact analysis platform that can inform users about the effects of COVID-19 spread and government orders on mobility and social distancing. The platform is being updated daily, to continuously inform decision-makers about the impacts of COVID-19 on their communities, using an interactive analytical tool. The research team has processed anonymized mobile device location data to identify trips and produced a set of variables, including social distancing index, percentage of people staying at home, visits to work and non-work locations, out-of-town trips, and trip distance. The results are aggregated to county and state levels to protect privacy, and scaled to the entire population of each county and state. The research team is making their data and findings, which are updated daily and go back to January 1, 2020, for benchmarking, available to the public to help public officials make informed decisions. This paper presents a summary of the platform and describes the methodology used to process data and produce the platform metrics.

2.
Transp Res Rec ; 2677(4): 168-180, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: covidwho-2320840

RESUMEN

The research team has utilized privacy-protected mobile device location data, integrated with COVID-19 case data and census population data, to produce a COVID-19 impact analysis platform that can inform users about the effects of COVID-19 spread and government orders on mobility and social distancing. The platform is being updated daily, to continuously inform decision-makers about the impacts of COVID-19 on their communities, using an interactive analytical tool. The research team has processed anonymized mobile device location data to identify trips and produced a set of variables, including social distancing index, percentage of people staying at home, visits to work and non-work locations, out-of-town trips, and trip distance. The results are aggregated to county and state levels to protect privacy, and scaled to the entire population of each county and state. The research team is making their data and findings, which are updated daily and go back to January 1, 2020, for benchmarking, available to the public to help public officials make informed decisions. This paper presents a summary of the platform and describes the methodology used to process data and produce the platform metrics.

3.
J Franklin Inst ; 360(10): 6846-6861, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: covidwho-2311178

RESUMEN

In this study, we investigate the COVID-19 propagation dynamics using a stochastic SIQR model with Gaussian white noise and semi-Markovian switching, focusing on the impacts of Gaussian white noise and semi-Markovian switching on the propagation dynamics of COVID-19. It is suggested that the fate of COVID-19 is entirely determined by the basic reproduction number R0, under mild extra conditions. By making sensitivity analysis on R0, we found that the effect of quarantine rate on R0 was more significant compared to transmission rate. Our results demonstrate that: (i) The presence of Gaussian white noise, while reducing the basic reproduction number R0 of COVID-19, also poses more challenges for the prediction and control of COVID-19 propagation. (ii) The conditional holding time distribution has a significant effect on the kinetics of COVID-19. (iii) The semi-Markov switching and Gaussian white noise can support irregular recurrence of COVID-19 outbreaks.

4.
Reg Sci Policy Prac ; 2022 Dec 05.
Artículo en Inglés | MEDLINE | ID: covidwho-2304367

RESUMEN

Mobility interventions in communities play a critical role in containing a pandemic at an early stage. The real-world practice of social distancing can enlighten policymakers and help them implement more efficient and effective control measures. A lack of such research using real-world observations initiates this article. We analyzed the social distancing performance of 66,149 census tracts from 3,142 counties in the United States with a specific focus on income profile. Six daily mobility metrics, including a social distancing index, stay-at-home percentage, miles traveled per person, trip rate, work trip rate, and non-work trip rate, were produced for each census tract using the location data from over 100 million anonymous devices on a monthly basis. Each mobility metric was further tabulated by three perspectives of social distancing performance: "best performance," "effort," and "consistency." We found that for all 18 indicators, high-income communities demonstrated better social distancing performance. Such disparities between communities of different income levels are presented in detail in this article. The comparisons across scenarios also raise other concerns for low-income communities, such as employment status, working conditions, and accessibility to basic needs. This article lays out a series of facts extracted from real-world data and offers compelling perspectives for future discussions.

5.
Front Public Health ; 10: 1041580, 2022.
Artículo en Inglés | MEDLINE | ID: covidwho-2142364

RESUMEN

Background: The outbreak of the new coronavirus-2019 (COVID-19) has had a significant impact on people's mental and physical health. Meanwhile, people's perceptions of risk may influence their emotional states and preventative behavior during an epidemic. Previous research have revealed the diversity and uniqueness of risk perception, and college students may have a different perspective on risk perception. The objective of this study was to describe the subtypes of risk perception for COVID-19 among college students in China, identify the subtypes' traits, and investigate their affecting variables. Methods: College students from 10 Chinese provinces participated in a cross-sectional study (n = 2,000) that from January 16 to 30, 2022. The latent profiles and influencing factors for risk perception were investigated using latent profile analysis, one-way analysis of variance, and multinomial logistical regression. Results: The sample group of this survey was 1,946 students, and the response rate was 97.3%. The best model was suggested to consist of three profiles: "neutral risk perception" (20.3%), "perception seriously without susceptible" (52.8%), and "low risk perception" (26.9%). Risk perception of COVID-19 was positively associated with attention to negation information (r = 0.372, p < 0.01), anxiety (r = 0.232, p < 0.01), and depression (r = 0.241, p < 0.01), and negatively associated with perceived social support (r = -0.151, p < 0.01). Logistic-regressions analyses mainly revealed that the risk perception of three profiles related to having chronic diseases (OR = 2.704, p < 0.01), medical major (OR = 0.595, p < 0.01; OR = 0.614, p < 0.05), without having COVID-19 confirmed cases around (OR = 0.539, p < 0.01), attention to negative information (OR = 1.073, p < 0.001; OR = 1.092, p < 0.001), and perceived social support (OR = 0.0.975, p < 0.01). Conclusions: The level of risk perception for COVID-19 among Chinese college students was unsatisfactory, and the risk perception of COVID-19 had significant group characteristics and heterogeneity. Colleges and public health practitioners could have a theoretical and empirical basis to implement risk perception intervention efforts by identifying latent subgroups during the COVID-19 epidemic.


Asunto(s)
COVID-19 , Humanos , Estudios Transversales , COVID-19/epidemiología , Estudiantes/psicología , China/epidemiología , Percepción
6.
Transportation Research Board; 2021.
No convencional en Inglés | Transportation Research Board | ID: grc-747483

RESUMEN

The research team has utilized privacy-protected mobile device location data, integrated with COVID-19 case data and census population data, to produce a COVID-19 impact analysis platform that can inform users about the effects of COVID-19 spread and government orders on mobility and social distancing. The platform is being updated daily, to continuously inform decision-makers about the impacts of COVID-19 on their communities using an interactive analytical tool. The research team has processed anonymized mobile device location data to identify trips and produced a set of variables including social distancing index, percentage of people staying at home, visits to work and non-work locations, out-of-town trips, and trip distance. The results are aggregated to county and state levels to protect privacy and scaled to the entire population of each county and state. The research team are making their data and findings, which are updated daily and go back to January 1, 2020, for benchmarking, available to the public in order to help public officials make informed decisions. This paper presents a summary of the platform and describes the methodology used to process data and produce the platform metrics.

7.
PLoS One ; 15(11): e0241468, 2020.
Artículo en Inglés | MEDLINE | ID: covidwho-917994

RESUMEN

In March of this year, COVID-19 was declared a pandemic, and it continues to threaten public health. This global health crisis imposes limitations on daily movements, which have deteriorated every sector in our society. Understanding public reactions to the virus and the non-pharmaceutical interventions should be of great help to fight COVID-19 in a strategic way. We aim to provide tangible evidence of the human mobility trends by comparing the day-by-day variations across the U.S. from January 2020 to early April 2020. Large-scale public mobility at an aggregated level is observed by leveraging mobile device location data and the measures related to social distancing. Our study captures spatial and temporal heterogeneity as well as the sociodemographic variations and teleworking trends regarding the pandemic propagation and the non-pharmaceutical mobility interventions. All metrics adapted capture decreased public movements after the national emergency declaration. The population staying home has increased in all states before the stay-at-home mandates implemented and becomes more stable after the order with a smaller range of fluctuation. The public had been taking active responses, voluntarily staying home more, to the in-state confirmed cases while the stay-at-home orders stabilize the variations. As the estimated teleworking rates also continue to incline throughout the study period, the teleworking trend can be another driving factor for the growing stay-at-home population. We confirm that there exists overall mobility heterogeneity between the income or population density groups. The study suggests that public mobility trends are in line with the government message urging to stay home. We anticipate our data-driven analysis offers integrated perspectives and serves as evidence to raise public awareness and, consequently, reinforce the importance of social distancing while assisting policymakers.


Asunto(s)
Infecciones por Coronavirus/patología , Movimiento , Neumonía Viral/patología , Betacoronavirus/aislamiento & purificación , COVID-19 , Uso del Teléfono Celular/estadística & datos numéricos , Infecciones por Coronavirus/epidemiología , Infecciones por Coronavirus/virología , Procesamiento Automatizado de Datos , Humanos , Pandemias , Neumonía Viral/epidemiología , Neumonía Viral/virología , SARS-CoV-2 , Análisis Espacio-Temporal , Estados Unidos/epidemiología
8.
Cell ; 182(2): 417-428.e13, 2020 07 23.
Artículo en Inglés | MEDLINE | ID: covidwho-342735

RESUMEN

Nucleotide analog inhibitors, including broad-spectrum remdesivir and favipiravir, have shown promise in in vitro assays and some clinical studies for COVID-19 treatment, this despite an incomplete mechanistic understanding of the viral RNA-dependent RNA polymerase nsp12 drug interactions. Here, we examine the molecular basis of SARS-CoV-2 RNA replication by determining the cryo-EM structures of the stalled pre- and post- translocated polymerase complexes. Compared with the apo complex, the structures show notable structural rearrangements happening to nsp12 and its co-factors nsp7 and nsp8 to accommodate the nucleic acid, whereas there are highly conserved residues in nsp12, positioning the template and primer for an in-line attack on the incoming nucleotide. Furthermore, we investigate the inhibition mechanism of the triphosphate metabolite of remdesivir through structural and kinetic analyses. A transition model from the nsp7-nsp8 hexadecameric primase complex to the nsp12-nsp7-nsp8 polymerase complex is also proposed to provide clues for the understanding of the coronavirus transcription and replication machinery.


Asunto(s)
Betacoronavirus/química , Betacoronavirus/enzimología , ARN Polimerasa Dependiente del ARN/química , Proteínas no Estructurales Virales/química , Adenosina Monofosfato/análogos & derivados , Adenosina Monofosfato/química , Adenosina Monofosfato/metabolismo , Adenosina Monofosfato/farmacología , Alanina/análogos & derivados , Alanina/química , Alanina/metabolismo , Alanina/farmacología , Antivirales/química , Antivirales/metabolismo , Antivirales/farmacología , Dominio Catalítico , ARN Polimerasa Dependiente de ARN de Coronavirus , Microscopía por Crioelectrón , Modelos Químicos , Modelos Moleculares , ARN Viral/metabolismo , SARS-CoV-2 , Transcripción Genética , Replicación Viral
9.
Science ; 368(6492): 779-782, 2020 05 15.
Artículo en Inglés | MEDLINE | ID: covidwho-47347

RESUMEN

A novel coronavirus [severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2)] outbreak has caused a global coronavirus disease 2019 (COVID-19) pandemic, resulting in tens of thousands of infections and thousands of deaths worldwide. The RNA-dependent RNA polymerase [(RdRp), also named nsp12] is the central component of coronaviral replication and transcription machinery, and it appears to be a primary target for the antiviral drug remdesivir. We report the cryo-electron microscopy structure of COVID-19 virus full-length nsp12 in complex with cofactors nsp7 and nsp8 at 2.9-angstrom resolution. In addition to the conserved architecture of the polymerase core of the viral polymerase family, nsp12 possesses a newly identified ß-hairpin domain at its N terminus. A comparative analysis model shows how remdesivir binds to this polymerase. The structure provides a basis for the design of new antiviral therapeutics that target viral RdRp.


Asunto(s)
Betacoronavirus/enzimología , ARN Polimerasa Dependiente del ARN/química , ARN Polimerasa Dependiente del ARN/ultraestructura , Proteínas no Estructurales Virales/química , Proteínas no Estructurales Virales/ultraestructura , Adenosina Monofosfato/análogos & derivados , Adenosina Monofosfato/metabolismo , Adenosina Monofosfato/farmacología , Alanina/análogos & derivados , Alanina/metabolismo , Alanina/farmacología , Antivirales/metabolismo , Antivirales/farmacología , Dominio Catalítico , ARN Polimerasa Dependiente de ARN de Coronavirus , Microscopía por Crioelectrón , Diseño de Fármacos , Modelos Moleculares , Complejos Multiproteicos/química , Complejos Multiproteicos/metabolismo , Complejos Multiproteicos/ultraestructura , Conformación Proteica en Lámina beta , Dominios Proteicos , ARN Polimerasa Dependiente del ARN/antagonistas & inhibidores , ARN Polimerasa Dependiente del ARN/metabolismo , SARS-CoV-2 , Proteínas no Estructurales Virales/antagonistas & inhibidores , Proteínas no Estructurales Virales/metabolismo
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