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Item type:Publication, Impact of urban facilities spatial inequality on sustainable travel mode(2024); ;Luz Flórez-Calderón ;Yasna Cortés; Marcelo Lufin<jats:p>With the implementation of sustainable development objectives in developing countries, urban planning, land use regulation, and urban mobility policies are expected to help reduce inequalities in access to urban facilities. Urban transport policies are also expected to encourage travel by non-motorised modes and public transport. These are considered to be the sustainable modes of urban transport. In this paper, we investigate how inequality of urban facilities impacts trips made by sustainable modes in the city of Santiago de Chile. We use a Poisson regression model and its geographical extension, the geographically weighted Poisson regression model (GWPR). The results suggest that the inequality of urban facilities impacts trips made by sustainable modes. The variables with the highest relevance are the spatial distribution of mixed land use, the spatial distribution of urban services related to transport infrastructure, primary and secondary education, as well as the spatial distribution of demographic variables related to people’s life cycle.</jats:p>Scopus© Citations 1 5 - Some of the metrics are blocked by yourconsent settings
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Item type:Publication, Structural brain abnormalities in schizophrenia in adverse environments: examining the effect of poverty and violence in six Latin American cities(2020) ;Nicolas A. Crossley ;Andre Zugman ;Francisco Reyes-Madrigal ;Leticia S. CzepielewskiMariana N. Castro<jats:title>Summary</jats:title><jats:sec id="S0007125020001439_sec_a1"><jats:title>Background</jats:title><jats:p>Social and environmental factors such as poverty or violence modulate the risk and course of schizophrenia. However, how they affect the brain in patients with psychosis remains unclear.</jats:p></jats:sec><jats:sec id="S0007125020001439_sec_a2"><jats:title>Aims</jats:title><jats:p>We studied how environmental factors are related to brain structure in patients with schizophrenia and controls in Latin America, where these factors are large and unequally distributed.</jats:p></jats:sec><jats:sec id="S0007125020001439_sec_a3" sec-type="methods"><jats:title>Method</jats:title><jats:p>This is a multicentre study of magnetic resonance imaging in patients with schizophrenia and controls from six Latin American cities. Total and voxel-level grey matter volumes, and their relationship with neighbourhood characteristics such as average income and homicide rates, were analysed with a general linear model.</jats:p></jats:sec><jats:sec id="S0007125020001439_sec_a4" sec-type="results"><jats:title>Results</jats:title><jats:p>A total of 334 patients with schizophrenia and 262 controls were included. Income was differentially related to total grey matter volume in both groups (<jats:italic>P</jats:italic> = 0.006). Controls showed a positive correlation between total grey matter volume and income (<jats:italic>R</jats:italic> = 0.14, <jats:italic>P</jats:italic> = 0.02). Surprisingly, this relationship was not present in patients with schizophrenia (<jats:italic>R</jats:italic> = −0.076, <jats:italic>P</jats:italic> = 0.17). Voxel-level analysis confirmed that this interaction was widespread across the cortex. After adjusting for global brain changes, income was positively related to prefrontal cortex volumes only in controls. Conversely, the hippocampus in patients with schizophrenia, but not in controls, was relatively larger in affluent environments. There was no significant correlation between environmental violence and brain structure.</jats:p></jats:sec><jats:sec id="S0007125020001439_sec_a5" sec-type="conclusions"><jats:title>Conclusions</jats:title><jats:p>Our results highlight the interplay between environment, particularly poverty, and individual characteristics in psychosis. This is particularly important for harsh environments such as low- and middle-income countries, where potentially less brain vulnerability (less grey matter loss) is sufficient to become unwell in adverse (poor) environments.</jats:p></jats:sec>Scopus© Citations 10 1 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Seroprevalence of Natural and Acquired Immunity against the SARS-CoV-2 Virus in a Population Cohort from Two Chilean Cities, 2020–2022(2023) ;Loreto Núñez-Franz ;Muriel Ramírez-Santana; ;Macarena Said<jats:p>Background: Chile has achieved the highest coverage for vaccines against the SARS-CoV-2 virus worldwide. Objective: To assess the progression of immunity (natural and acquired by vaccine) in a cohort from two Chilean cities. Methods: Individuals (n = 386) who participated in three phases of population-based serial prevalence studies were included (2020–2021 and 2022). Presence of SARS-CoV-2 antibodies was measured in serum. Data including time of vaccination and type of vaccine received were analysed with descriptive statistics. Results: Seroprevalence was 3.6% in the first round and increased to 96.9% in the second and 98.7% in the third. In the third round, 75% of individuals who had received the basal full scheme were seropositive at 180 days or more since their last dose; 98% of individuals who received one booster dose were seropositive at 180 days or more, and 100% participants who received two boosters were seropositive, regardless of time since their last dose. Participants receiving mRNA vaccines had higher seroprevalence rates over time. Conclusions: The high vaccination coverage in Chile enabled the population to maintain high levels of antibodies. Vaccination boosters are essential to maintain immunity over time, which also depends on the type of vaccine administered.</jats:p>1Scopus© Citations 12 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Perceived barriers and facilitators for adhering to COVID-19 preventive measures in Chile: a qualitative study in three large cities(2023); ; ;Francisca Vezzani ;Consuelo RobledoAlice Blukacz<jats:title>Abstract</jats:title><jats:sec> <jats:title>Background</jats:title> <jats:p>Globally, it has been reported that different social determinants of health -structural, sociodemographic, economic, living conditions and cultural factors- may affect opportunities to adhere to prevention measures against SARS-CoV-2. The objective of this study was to explore the perceptions around barriers and facilitators for adherence to COVID-19 prevention measures among the adult population residing in three large cities in Chile from a social determinants of health perspective.</jats:p> </jats:sec><jats:sec> <jats:title>Methods</jats:title> <jats:p>Qualitative paradigm, multiple case-study design. Online semi-structured interviews were conducted with men and women aged 18 and over from different socioeconomic groups residing in three large cities. For participant recruitment and selection, purposive contacts were made based on community and social media networks, followed by snowball sampling. Saturation was reached at 61 participants, after which a thematic analysis was carried out with the support of AtlasTi software. The Ethics Committee of the Universidad del Desarrollo in Chile approved this study.</jats:p> </jats:sec><jats:sec> <jats:title>Results</jats:title> <jats:p>The main perceived barriers to adherence to COVID-19 preventive measures are linked to structural social determinants of health such as income, occupation, gender, access to basic supplies, and housing. Perceived facilitators are the fear of contagion and the incorporation of measures into daily habits. The social communication of preventive measures by health authorities is perceived as punitive, affecting adherence once the fear of contagion decreased in the country. It is also perceived that the recommended preventive measures are disconnected from communities’ cultural practices and people´s identity, as well as affected by gender inequities and socioeconomic conditions that stakeholders in the country do not sufficiently address.</jats:p> </jats:sec><jats:sec> <jats:title>Conclusion</jats:title> <jats:p>Study findings suggest that adherence to preventive measures, such as social distancing, mask use, and hand washing, could be promoted through their incorporation into the daily life habits of people and communities. These measures should consider the structural social determinants that generate multiple barriers to adherence, like poverty, occupational risks, and overcrowding. Socio-cultural dimensions of health and everyday risks need further understanding among the different communities in the country, allowing for differences in viewpoints and practices based on gender, age, place, and social identity.</jats:p> </jats:sec>Scopus© Citations 2 1 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, A city of cities: Measuring how 15-minutes urban accessibility shapes human mobility in Barcelona(2021) ;Eduardo Graells-Garrido ;Feliu Serra-Burriel ;Francisco Rowe ;Fernando M. CucchiettiPatricio Reyes<jats:p>As cities expand, human mobility has become a central focus of urban planning and policy making to make cities more inclusive and sustainable. Initiatives such as the “15-minutes city” have been put in place to shift the attention from monocentric city configurations to polycentric structures, increasing the availability and diversity of local urban amenities. Ultimately they expect to increase local walkability and increase mobility within residential areas. While we know how urban amenities influence human mobility at the city level, little is known about spatial variations in this relationship. Here, we use mobile phone, census, and volunteered geographical data to measure geographic variations in the relationship between origin-destination flows and local urban accessibility in Barcelona. Using a Negative Binomial Geographically Weighted Regression model, we show that, globally, people tend to visit neighborhoods with better access to education and retail. Locally, these and other features change in sign and magnitude through the different neighborhoods of the city in ways that are not explained by administrative boundaries, and that provide deeper insights regarding urban characteristics such as rental prices. In conclusion, our work suggests that the qualities of a 15-minutes city can be measured at scale, delivering actionable insights on the polycentric structure of cities, and how people use and access this structure.</jats:p>Scopus© Citations 167 1 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, A global metagenomic map of urban microbiomes and antimicrobial resistance(2021) ;David Danko ;Daniela Bezdan ;Evan E. Afshin ;Sofia AhsanuddinChandrima BhattacharyaScopus© Citations 292 6 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Photochemical sensitivity to emissions and local meteorology in Bogotá, Santiago, and São Paulo(2022) ;Rodrigo J. Seguel ;Laura Gallardo ;Mauricio Osses ;Néstor Y. RojasThiago Nogueira<jats:p>This study delves into the photochemical atmospheric changes reported globally during the pandemic by analyzing the change in emissions from mobile sources and the contribution of local meteorology to ozone (O3) and particle formation in Bogotá (Colombia), Santiago (Chile), and São Paulo (Brazil). The impact of mobility reductions (50%–80%) produced by the early coronavirus-imposed lockdown was assessed through high-resolution vehicular emission inventories, surface measurements, aerosol optical depth and size, and satellite observations of tropospheric nitrogen dioxide (NO2) columns. A generalized additive model (GAM) technique was also used to separate the local meteorology and urban patterns from other drivers relevant for O3 and NO2 formation. Volatile organic compounds, nitrogen oxides (NOx), and fine particulate matter (PM2.5) decreased significantly due to motorized trip reductions. In situ nitrogen oxide median surface mixing ratios declined by 70%, 67%, and 67% in Bogotá, Santiago, and São Paulo, respectively. NO2 column medians from satellite observations decreased by 40%, 35%, and 47%, respectively, which was consistent with the changes in mobility and surface mixing ratio reductions of 34%, 25%, and 34%. However, the ambient NO2 to NOx ratio increased, denoting a shift of the O3 formation regime that led to a 51%, 36%, and 30% increase in the median O3 surface mixing ratios in the 3 respective cities. O3 showed high sensitivity to slight temperature changes during the pandemic lockdown period analyzed. However, the GAM results indicate that O3 increases were mainly caused by emission changes. The lockdown led to an increase in the median of the maximum daily 8-h average O3 of between 56% and 90% in these cities.</jats:p>Scopus© Citations 15 2 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Scaling behavior of public procurement activity(2021) ;António Curado ;Bruno Damásio ;Sara Encarnação; Flávio L. PinheiroPublic procurement refers to the purchase by public sector entities—such as government departments or local authorities—of Services, Goods, or Works. It accounts for a significant share of OECD countries’ expenditures. However, while governments are expected to execute them as efficiently as possible, there is a lack of methodologies for an adequate comparison of procurement activity between institutions at different scales, which represents a challenge for policymakers and academics. Here, we propose using methods borrowed from urban scaling laws literature to study public procurement activity among 278 Portuguese municipalities between 2011 and 2018. We find that public procurement expenditure scales sublinearly with population size, indicating an economy of scale for public spending as cities increase their population size. Moreover, when looking at the municipal Scale-Adjusted Indicators (the deviations from the scaling law) by contract categories—Works, Goods, and Services—we are able to identify a richer local characterisation of municipalities based on the similarity of procurement activity. These results make up a framework for quantitatively studying local public expenditure by enabling policymakers a more appropriate foundation for comparative analysis.3Scopus© Citations 7