关键词： COVID-19   Discrimination   Transit   Understanding America Study   Walking  

摘要： A rise in reporting and media coverage of negative social interactions and experiences of racism in transit and other public environments suggests that perceived discrimination may have affected the travel behavior and health of people of color during the COVID-19 pandemic. In this study, to examine relationships between race, perceived discrimination, transit use, and walking behavior, we draw on data collected in 20 waves of the Understanding America Study (UAS) COVID-19 tracking survey, fielded July 2020–July 2021. Importantly, we find that transit use among minorities continued during the pandemic at higher rates, especially among Black and Hispanic respondents, despite non-White respondents reporting more frequent perceptions of discrimination. Our linear mixed-effect model results further indicate that non-White respondents were notably more likely to use transit. Examining walking behavior, we find that White and Asian respondents consistently reported more walking than Black and Hispanic respondents, even when controlling for income. Crucially, we found that in the presence of controls, while large disparities were observed in both walking and transit behavior based on race, perceived discrimination had little to no effect. While disparities in travel behavior based on race are evidently better explained by structural factors as opposed to overt, individual-level discrimination, planners, policymakers, and designers should nevertheless give greater consideration to micro- and macro-scale interventions that facilitate safe transit use and walking for racial and ethnic minorities.

关键词： Public transport   Passenger crowding   Discrete choice modelling   Real-time crowding information   RTCI   Willingness to wait   COVID-19  

摘要： Travel preferences in public transport (PT) have been substantially affected by the COVID-19 crisis, with rising emphasis on on-board safety and comfort aspects. Hence, real-time crowding information (RTCI) might have become even more instrumental in supporting travel decisions in congested urban PT systems. This study investigates the willingness to wait (WTW) to reduce (or avoid) overcrowding with RTCI in urban PT (bus and tram) journeys, analysing pre- vs. post-COVID travel behaviour attitudes. Stated-preference data and (subsequently estimated) choice models indicate that, while the pre-COVID WTW was primarily driven by mere possibility to avoid an overcrowded first departure, the post-COVID propensity to wait is strongly associated with expectations of seat availability in second departure as well. The ex-post WTW with RTCI seems to have become less-dependent on individual characteristics and more prominent for time-critical (obligatory) trips as well. Our findings underpin the rising relevance of passenger overcrowding in urban PT journeys. Moreover, they help better understand the potential of RTCI in post-pandemic recovery of PT ridership.

关键词： Compartmental epidemic models   Covid-19   Dynamic simulations   Equilibrium states  

摘要： We introduce a generalization of the 4 compartments SVIR epidemic model discussed in [1] for the first time. Our model has K+4 compartments. K-1 of these compartments represent additional subsequent vaccination stages not considered in the original SVIR model, while a further compartment accounts for dead people. We analyze the equilibrium points of the model. A time-varying parameters version of it, having K = 3 vaccination compartments, is then calibrated to Italian COVID-19 dataset. This analysis is carried out for three specific sub-periods: the first one, ranging from February 24th, 2020, up to December 26th 2020, when no vaccines were available; the second one, from the December 27th, 2020 up to December 31st, 2021, during which the Delta variant of the virus prevailed and Delta-targeted vaccination doses were administered to the population for the first time; finally, the last considered period is ranging from January 10th, 2022 up to June 3rd, 2022, and it was characterized by the diffusion of the Omicron variant. To tackle the problem of undetected infected or undetected recovered people we adopt an approach relying on different scenarios. The calibration of the model uses the property that the discrete-time version of it turns out to be explicitly solvable with respect to the parameters, hence providing a daily estimate of the involved parameters. This produces meaningful evolution patterns of the COVID-19 epidemic which allow a better understanding of the diffusive behavior of the pandemic along time. Lastly a statistical analysis of the epidemiological parameters estimators supports the non stationarity of their time series.

关键词： COVID-19   Mathematical model   Control reproduction number   Asymptotic stability   Parameter estimation   Global sensitivity analysis   Caputo fractional derivative   SIR EPIDEMIC MODEL   DISEASE  

摘要： This study focuses on formulating and analysing a COVID-19 transmission dynamics model using integer and fractional-order derivatives in the Caputo sense. The model considers two doses of vaccination, confinement, and treatment with limited resources. The control reproduction number is computed and the asymptotic stability analysis of the disease-free equilibrium is proved. We also prove the existence of at least one endemic equilibrium whenever R- c > 1. Using real data from Germany, we calibrate our models by performing parameter estimations. We find that the control reproduction number is approximately equal to 1.90, which implies that the disease remains endemic in Germany. We also perform global sensitivity analysis by computing partial rank correlation coefficients (PRCC) between R- c (respectively compartments of infected individuals) and each model parameter. By fixing vaccine coverage at 70%, we observe that it might be more effective to increase the vaccine efficacy than increasing the numbers of vaccinated people. After that, we formulate the corresponding fractional model in the Caputo sense, proving positivity, boundedness, existence, and uniqueness of solutions. We calculate the control reproduction number of the fractional model, and prove the asymptotic stability of the DFE, and existence of at least one endemic equilibrium point. We find from numerical simulations, that for a long-term forecasting, it seems better to use a fractional derivative in the range phi is an element of (0 , 0 .87] than using just ordinary derivatives. Indeed, for this range of the fractional-order parameter, daily detected cases are closer to those the classical model predicts.

关键词： Community   Heterogeneity   AIDS   Incidence   Statistical estimation   Geographical variations  

摘要： Background The number of people undergoing voluntary HIV testing has abruptly decreased since 2020. The geographical heterogeneity of HIV infection and the impact of COVID-19 on the diagnosis of HIV at regional level are important to understand. This study aimed to estimate the HIV incidence by geographical region and understand how the COVID-19 pandemic influenced diagnosis of HIV. Methods We used an extended back-calculation method to reconstruct the epidemiological dynamics of HIV/AIDS by geographical region. We used eight regions: Tokyo, the capital of Japan, Hokkaido plus Tohoku, Kanto plus Koshinetsu (excluding Tokyo), Hokuriku, Tokai, Kinki, Chugoku plus Shikoku, and Kyushu plus Okinawa. Four different epidemiological measurements were evaluated: (i) estimated HIV incidence, (ii) estimated rate of diagnosis, (iii) number of undiagnosed HIV infections, and (iv) proportion of HIV infections that had been diagnosed. Results The incidence of HIV/AIDS during the COVID-19 pandemic from 2020 to 2022 increased in all regions except Kanto/Koshinetsu (51.3 cases/year), Tokyo (183.9 cases/year), Hokuriku (1.0 cases/year), and Tokai (43.1 cases/year). The proportion of HIV infections that had been diagnosed only exceeded 90% in Tokyo (91.7%, 95% confidence interval (CI): 90.6, 93.3), Kanto/Koshinetsu (91.0%, 95% CI: 87.3, 97.8), and Kinki (92.5%, 95% CI: 90.4, 95.9). The proportion of infections that had been diagnosed was estimated at 83.3% (95% CI: 75.1, 98.7) in Chugoku/Shikoku and 80.5% (95% CI: 73.9, 91.0) in Kyusyu/Okinawa. Conclusions In urban regions with major metropolitan cities, including Tokyo, Kinki, and Kanto/Koshinetsu, the number of undiagnosed HIV infections is substantial. However, the proportion of undiagnosed infections was estimated to be smaller than in other regions. The diagnosed proportion was the lowest in Kyusyu/Okinawa (80.5%), followed by Chugoku/Shikoku and Hokkaido/Tohoku. The level of diagnosis in those regional prefectures may have been m

关键词： Nitrous acid   Nitrogen oxides   COVID-19   HONO budget   Unknown sources   NITROUS-ACID HONO   URBAN SITE   HETEROGENEOUS PRODUCTION   ATMOSPHERIC CHEMISTRY   VERTICAL PROFILES   BOUNDARY-LAYER   OH REACTIVITY   RURAL SITE   NO2   EMISSIONS  

摘要： HONO is a critical precursor of center dot OH, but its sources are controversial due to its complex formation mechanism. This study conducted comprehensive observations in Zhengzhou from April 26 to May 11, 2022. Low NO x concentrations were observed during the Covid epidemic period (EP) (10.4 +/- 3.0 ppb), compared to the pre -epidemic period (PEP) (12.5 +/- 3.8 ppb). The mean HONO concentration during EP (0.53 +/- 0.34 ppb) was 0.09 ppb lower than that during PEP (0.62 +/- 0.53 ppb). The decrease in HONO concentration during EP came mainly at night due to the reduction in the direct emission (P emi ) (0.03 ppb/hr), the homogeneous reaction between center dot OH and NO (P OH + NO ) (0.02 ppb/hr), and the heterogeneous conversion of NO 2 on the ground (0.01 ppb/hr). Notably, there was no significant change in daytime HONO concentration. The daytime HONO budget indicated that the primary HONO sources during PEP were the nitrate photolysis ( P nitrate ), followed by the P OH + NO , P emi , the photo -enhanced reaction of NO 2 on the ground ( P ground + hv ) and aerosol surface ( P aerosol + hv ). The primary HONO sources were P nitrate , P OH + NO , P emi , and P aerosol + hv during EP, respectively. The missing source has a high correlation with solar radiation, there might be other photo -related HONO sources or the contributions of photosensitized reactions were underestimated. In the extremely underestimated cases, HONO production rates from the P nitrate , P ground + hv , and P aerosol + hv increased by 0.17, 0.10, and 0.10 ppb/hr during PEP, 0.23, 0.13, and 0.16 ppb/hr during EP, and P nitrate was still the primary source during both PEP and EP. (c) 2024 The Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences. Published by Elsevier B.V.

关键词： COVID‐19   choledocholithiasis   endoscopic retrograde cholangiopancreatography   pandemic   state of emergency  

摘要： Objectives:This study aimed to determine the impact of the coronavirus disease 2019 (COVID-19) pandemic on the treatment of acute cholangitis caused by choledocholithiasis. Methods:The Japanese government declared a state of emergency in April 2020 due to the COVID-19 pandemic. We retrospectively reviewed the medical records of 309 patients who underwent endoscopic retrograde cholangiopancreatography (ERCP) for acute cholangitis caused by choledocholithiasis between April 2017 and December 2022. Results:Patients were categorized into a pregroup ( = 134) and a postgroup ( = 175), depending on whether they were diagnosed before or after the state of emergency declaration. The total number of ERCP cases and the number of ERCP cases with endoscopic stone removals increased after the state of emergency declaration. Compared with the pregroup, the numbers of patients with performance status of 0-1 and surgically altered anatomy increased, whereas the numbers of patients taking oral antiplatelets or anticoagulants and those with cerebrovascular disease decreased in the postgroup. The number of single-stage endoscopic stone removals increased and hospital stays were significantly shorter in the postgroup. No differences in adverse event rates were detected between the two groups. Conclusions:Although our hospital provides tertiary care, the number of patients with cholangitis in good general condition and no underlying disease increased after the state of emergency declaration. The COVID-19 pandemic resulted in an increase in the number of single-stage endoscopic treatments and shortened hospital stays for patients with acute cholangitis caused by choledocholithiasis. No safety issues with ERCP were detected, even during the pandemic.

关键词： G11   G14   G15   Q56   SRI   SIN   ETFs   COVID-19   Financial crises   ESG  

摘要： This study analyses the performance dynamics of socially responsible investment (SRI) and SIN investment exchange-traded funds (ETFs) during the COVID-19 pandemic in the United States. Utilising a GARCH methodology, the research examines ETF returns while considering significant COVID-19-related events to assess their impact. The study diverges from the conventional narrative of SIN stocks’ superiority by illustrating the resilience and outperformance of SRI ETFs in terms of returns and volatility stability during the pandemic. This finding challenges previous assertions in the literature and suggests a potential paradigm shift in investment strategies during periods of global crisis. The results underscore the importance of integrating Environmental, Social, and Governance (ESG) factors into investment decisions, especially in turbulent times. This study offers investors actionable insights into the benefits of SRI ETFs, demonstrating their ability to provide stable returns and reduced risk during economic downturns. Fund managers can leverage these findings to align their portfolios with ESG principles, enhancing resilience against future crises. Policymakers can also draw on this evidence to promote sustainable investment frameworks that support long-term financial stability. Overall, this study contributes to the evolving discourse on sustainable investing, positioning SRI as a viable approach that balances financial performance with societal impact.

关键词： EQ-5D-5L   long COVID   quality of life  

摘要： Objective We aimed to assess physical and psychosomatic manifestations of patients with long COVID and their association with a decreased patient’s quality of life (QOL) or different times elapsed since the COVID-19 diagnosis. Methods This is a cross-sectional study. We retrospectively collected the clinical characteristics of adult patients who had tested positive for SARS-CoV-2 and had symptoms at least as early as 4 weeks after COVID-19 in México City between April 2020 and February 2021. A total of 179 were included. They answered questions to define chronic symptoms. The Sniffin’ Sticks Screening 12 test olfactory evaluation was performed. The diminish of QOL was defined by ≥10 points in the EuroQol visual analog scale between pre- and post-COVID-19, and each dimension of EQ-5D-5L test was evaluated. Chi-square test, Fisher’s exact test, Student t test, Wilcoxon rank-sum, and signed-rank test were used as required. A backward stepwise logistic regression analysis determined the factors associated with a decrease in QOL. All analyses were performed using R software version 3.6.3 (R Foundation). Results In the multivariable analysis, post-COVID-19 pain/discomfort (adjusted odds ratio [aOR] 2.5 [1.66-9.68]; P  = .01), anxiety/depression (aOR 13 [1.44-17.23]; P  = .03), and persistence of ≥3 symptoms (aOR 2.6 [0.96-7.47]; P  = .05) remained statistically significant associated with decreased QOL. Conclusions Patients with long COVID-19 have decreased QOL mainly associated with pain/discomfort, anxiety/depression, and ≥3 persistent symptoms. Our findings enhanced the notion of a strong psychosomatic factors involved with long COVID-19. Therefore, these patients might benefit from neuropsychological rehabilitation, although the effect of such interventions should be evaluated.