24 research outputs found
Tracking the emergence of disparities in the subnational spread of COVID-19 in Brazil using an online application for real-time data visualisation: A longitudinal analysis
Background: Brazil is one of the countries worst affected by the COVID-19 pandemic with over 20 million cases and 557,000 deaths reported by August 2021. Comparison of real-time local COVID-19 data between areas is essential for understanding transmission, measuring the effects of interventions, and predicting the course of the epidemic, but are often challenging due to different population sizes and structures. Methods: We describe the development of a new app for the real-time visualisation of COVID-19 data in Brazil at the municipality level. In the CLIC-Brazil app, daily updates of case and death data are downloaded, age standardised and used to estimate the effective reproduction number (Rt). We show how such platforms can perform real-time regression analyses to identify factors associated with the rate of initial spread and early reproduction number. We also use survival methods to predict the likelihood of occurrence of a new peak of COVID-19 incidence. Findings: After an initial introduction in S\~o Paulo and Rio de Janeiro states in early March 2020, the epidemic spread to northern states and then to highly populated coastal regions and the Central-West. Municipalities with higher metrics of social development experienced earlier arrival of COVID-19 (decrease of 11·1 days 95% CI:8.9,13.2 in the time to arrival for each 10% increase in the social development index). Differences in the initial epidemic intensity (mean Rt) were largely driven by geographic location and the date of local onset. Interpretation: This study demonstrates that platforms that monitor, standardise and analyse the epidemiological data at a local level can give useful real-time insights into outbreak dynamics that can be used to better adapt responses to the current and future pandemics. Funding: This project was supported by a Medical Research Council UK (MRC-UK) -S{\~{a}}o Paulo Research Foundation (FAPESP) CADDE partnership award (MR/S0195/1 and FAPESP 18/14389-0
Dapagliflozin and Kidney Outcomes in Hospitalized Patients with COVID-19 Infection:An Analysis of the DARE-19 Randomized Controlled Trial
Background and objectives: Patients who were hospitalized with coronavirus disease 2019 (COVID-19) infection are at high risk of AKI and KRT, especially in the presence of CKD. The Dapagliflozin in Respiratory Failure in Patients with COVID-19 (DARE-19) trial showed that in patients hospitalized with COVID-19, treatment with dapagliflozin versus placebo resulted in numerically fewer participants who experienced organ failure or death, although these differences were not statistically significant. We performed a secondary analysis of the DARE-19 trial to determine the efficacy and safety of dapagliflozin on kidney outcomes in the overall population and in prespecified subgroups of participants defined by baseline eGFR. Design, setting, participants, & measurements: The DARE-19 trial randomized 1250 patients who were hospitalized (231 [18%] had eGFR <60 ml/min per 1.73 m2) with COVID-19 and cardiometabolic risk factors to dapagliflozin or placebo. Dual primary outcomes (time to new or worsened organ dysfunction or death, and a hierarchical composite end point of recovery [change in clinical status by day 30]), and the key secondary kidney outcome (composite of AKI, KRT, or death), and safety were assessed in participants with baseline eGFR <60 and ≥60 ml/min per 1.73 m2. Results: The effect of dapagliflozin versus placebo on the primary prevention outcome (hazard ratio, 0.80; 95% confidence interval, 0.58 to 1.10), primary recovery outcome (win ratio, 1.09; 95% confidence interval, 0.97 to 1.22), and the composite kidney outcome (hazard ratio, 0.74; 95% confidence interval, 0.50 to 1.07) were consistent across eGFR subgroups (P for interaction: 0.98, 0.67, and 0.44, respectively). The effects of dapagliflozin on AKI were also similar in participants with eGFR <60 ml/min per 1.73 m2 (hazard ratio, 0.71; 95% confidence interval, 0.29 to 1.77) and ≥60 ml/min per 1.73 m2 (hazard ratio, 0.69; 95% confidence interval, 0.37 to 1.29). Dapagliflozin was well tolerated in participants with eGFR <60 and ≥60 ml/min per 1.73 m2. Conclusions: The effects of dapagliflozin on primary and secondary outcomes in hospitalized participants with COVID-19 were consistent in those with eGFR below/above 60 ml/min per 1.73 m2. Dapagliflozin was well tolerated and did not increase the risk of AKI in participants with eGFR below or above 60 ml/min per 1.73 m2
Efeito da interação do nicosulfuron e chlorpyrifos sobre o banco de sementes e os atributos microbianos do solo
Colopexia incisional por celiotomia ou transparietal auxiliada por laparoscopia em cães
What are we missing when we measure accessibility? : Comparing calculated and self-reported accounts among older people
Accessibility is increasingly recognised as a key purpose of transport policies. Most of the common practices found both in academic studies and policy planning draw on relatively simple accessibility measures taken as ‘objective’ indicators that only focus on the interaction between land use and transport. Relatively little attention has been paid to heterogeneity in individual characteristics and in self-reported perceptions of accessibility (‘subjective’ indicators), and the corresponding differences with respect to available modal options. This study includes a comparison of (1) ‘objective’ indicators of accessibility to key activities by various modes of transport; and (2) individuals' own perceptions of their capability to access valuable out-of-home activities and the modal options available to them. This study examines the key differences between the two representations of accessibility. The calculated measure was developed using door-to-door travel times to supermarkets and healthcare centres using OpenTripPlanner. The self-reported measure was based on a dedicated capability-oriented travel survey of people aged 65–79 in Sweden's large metropolitan regions: Stockholm, Gothenburg and Malmö. The data were analysed using descriptive statistics and binary and multinomial logistic regressions. The results of this study allow us to gain a greater insight into the ways in which the two accounts differ and can complement one another. We find that conventional methods, by overlooking the heterogeneity in people's perceptions of their accessibility, tend to overestimate accessibility levels and underestimate accessibility inequalities. This study shows how perceived accounts of accessibility can be incorporated into conventional accessibility models and improve accessibility analyses.Research funding provided by K2 – The Swedish Knowledge Centre for Public Transport (grant numbers 2020012 and 2016003). </p
Estimating public transport emissions from General Transit Feed Specification data
This paper introduces the gtfs2emis model, a bottom-up method available as an R package to estimate emissions of public transport systems. The method uses General Transit Feed Specification (GTFS) data, a standard format for public transport data widely adopted worldwide, which makes the method easily applicable to cities with limited data. The model requires a GTFS feed of a given transport system and a table with general characteristics of the vehicle fleet profile. The package can estimate over 16 pollutants and energy consumption based on emission factor models from Europe, the United States, and Brazil. It also includes functions to help users examine how emissions are distributed across space, at different times of the day, and by types of vehicles. This paper presents a reproducible example of the city of São Paulo (Brazil) to demonstrate the gtfs2emis package and to discuss the potential applications and limitations of the proposed model
Evaluating the impact of public transport travel time inaccuracy and variability on socio-spatial inequalities in accessibility
Urban accessibility by public transport has been attracting increasing attention from researchers and transport agencies in recent years. Many of the studies rely on public transport scheduled timetables from GTFS data to calculate accessibility indicators, overlooking the ways in which inaccuracies in scheduled levels of service, as well as day-to-day travel time variability, might impact different socioeconomic groups. This might generate unrealistic or biased results when analyzing accessibility socio-spatial inequalities and assessing transport projects. In this study, we consolidate a method to correct timetables of GTFS feeds based on historical GPS data, and use the city of Fortaleza, Brazil, to show how accessibility to work opportunities based on these two accounts can influence the results of accessibility analyses due to two issues: data inaccuracy and day-to-day travel time variabilities. We use 1-month archived GPS data to create new GTFS timetables that represent both a median level of service and a variability-state level of service; then we use these estimated GTFS to examine the impact of travel time inaccuracy and day-to-day variability on accessibility levels. Results show that, due to the problem of data inaccuracy, the scheduled GTFS underestimates accessibility by 1.5% on average, but in some areas accessibility estimates can be over or underestimated by more than 40%, with significant impact in low income regions. We also find that the variability of travel times have a significant impact of 50% on average on accessibility estimates. This impact is unequally distributed both spatially and across income groups, raising accessibility inequality by 30%. The underlying causes of these impacts are related to several factors, including the GTFS feed\u27s quality, the high concentration of jobs in the city center, and higher travel time variability in the corridors that connect lower-income areas to the city center. These results highlight the importance of considering both inaccuracy and day-to-day variability issues in public transport travel times when estimating accessibility levels and evaluating transport projects, particularly from an equity perspective
Measuring just accessibility within planetary boundaries
Our societies are wrestling with the problem of how to provide a good life for all without overconsuming environmental resources. Consequently, the search for approaches that simultaneously inspect the environmental and social goals of sustainability have become increasingly popular in many disciplines. In transport research, accessibility is a key tool to characterize linkages between people, transport, and land use. In the current paper, we propose a conceptual framework for measuring just accessibility within planetary boundaries. We first carry out a review of transport studies and discover a substantial body of literature on accessibility and social disadvantage, much vaster compared to the body of literature around environmental and ecological impacts of accessibility. We also show a gap in approaches that have integrated these two perspectives. Building on the review, we move forward by suggesting a conceptual framework for incorporating environmental and social sustainability goals in accessibility research. We conclude the paper by pointing to some key challenges and research avenues related to the framework, including (i) dealing with uncertainty and complexity in socio-ecological thresholds, (ii) developing ways to measure accessibility through other metrics than travel time, and (iii) integrating both quantitative and qualitative data.Our societies struggle to provide a good life for all without overconsuming environmental resources. Consequently, scholarly search for approaches to meet environmental and social goals of sustainability have become popular. In transport research, accessibility is a key tool to characterise linkages between people, transport, and land use. In the current paper, we propose a conceptual framework for measuring just accessibility within planetary boundaries. We reviewed transport studies and discovered a substantial literature body on accessibility and social disadvantage, much vaster compared to the literature around environmental and ecological impacts of accessibility. We also show a gap in approaches that have integrated these two perspectives. Building on the review, we suggest a conceptual framework for incorporating environmental and social sustainability goals in accessibility research. We conclude the paper by pointing to key challenges and research avenues related to the framework, including (i) dealing with uncertainty and complexity in socio-ecological thresholds, (ii) integrating environmental limits into the conceptualisations of transport equity, (iii) measuring accessibility through other costs than travel time, and (iv) integrating both quantitative and qualitative data.Peer reviewe
The impact of transit monetary costs on transport inequality
Transport inequality analyses are often informed by accessibility estimates based solely on travel time impedance, ignoring other elements that might hinder access to activities, such as the monetary cost of a trip. This paper examines how and to what extent simultaneously incorporating both time and monetary costs into accessibility measures may impact transport inequality assessment. We calculate job accessibility by transit in the city of Rio de Janeiro, Brazil, using cumulative opportunity measures under distinct combinations of temporal and monetary thresholds, and compare how inequality levels vary across different scenarios. We find that the most common research practice of disregarding monetary costs tends to overestimate accessibility levels. However, stricter monetary constraints do not necessarily result in more unequal scenarios. How accessibility inequality is affected by monetary costs is highly dependent on what combinations of temporal and monetary cut-offs are considered in the analysis. In the case of Rio, opting for lower monetary thresholds when looking at shorter trips leads to inequality levels lower than those found in the no monetary threshold scenario, but results in higher inequality levels when allowing for longer trips. We find that the impact of monetary costs on transport inequality estimates depend on a complex interaction between fare policies, the spatial organization and operational characteristics of transit systems, and the spatial co-distribution of opportunities and residential locations. The paper thus highlights that conclusions and policy recommendations derived from transport inequality analyses can be affected in non-intuitive ways by the interplay between temporal and monetary constraints. Future research should investigate how different combinations of travel time and monetary costs thresholds affect inequality estimates in different contexts
Caracterización de los parámetros neutrónicos del reactor Triga IPR-R1 con el código SCALE6.0 (KENO VI)
KENO
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VI es un código de transporte neutrónico en el sistema SCALE6.0 que utiliza
el método de Monte Carlo para cálculos de criticidad en sistemas nucleares. Se ha construido
un modelo en 3D para caracterizar parámetros neutrónicos del reactor
de investigación TRIGA
IPR
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R1. Se han comparado los valores encontrados con los obtenidos por el código MCNP5 y
experimentales con el propósito de validar esta metodología.Faria De Castro, V.; Miró Herrero, R.; Mello Da Silva, CA.; Pereira, C.; Verdú Martín, GJ.; Barrachina Celda, TM.; Dalle, H. (2011). Caracterización de los parámetros neutrónicos del reactor Triga IPR-R1 con el código SCALE6.0 (KENO VI). Grupo Senda. http://hdl.handle.net/10251/34071S10