Large Latin American Research Articles

Abstract Su505: Impact of a Targeted Automated External Defibrillator (AED) Program on Survival After Ventricular Fibrillation Cardiac Arrest in the Sao Paulo Metropolitan Subway System: A Landmark Initiative in Latin America

The targeted Automated External Defibrillator (AED) program in the Sao Paulo Metro has yielded promising results in improving survival rates for individuals experiencing out-of-hospital cardiac arrest (OHCA) due to ventricular arrhythmias. A longitudinal observational study conducted from September 2006 to November 2023 assessed the program's impact on survival outcomes. The implementation of the full program led to a significant improvement in survival to hospital discharge with minimal neurological impairment (0% vs. 43%, P=0.001). These findings underscore the importance of a targeted AED program in improving survival outcomes for OHCA, particularly in densely populated urban environments such as the Sao Paulo Metro. The short interval between arrest and defibrillation emerged as a critical factor in achieving favorable long-term, neurologically intact survival rates. The success of this program advocates for the strategic expansion of targeted AED initiatives in other large Latin American cities, emphasizing the potential to save lives and enhance public health outcomes through proactive emergency medical response measures.

Socioeconomic Status and Local Biodiversity as Predictors of Attitudes towards Nature among High School Students in a Latin American Metropolis.

Urbanization and biodiversity loss disconnect humans from nature and may limit pro-environmental actions. Although, a growing body of knowledge exists on people's attitudes towards nature, the majority focuses on the influence of socio-environmental factors. Significant variations in socioeconomic and educational levels in urban areas affect access to biodiversity. In this study, we aim to identify the socio-environmental variables that are associated with people's attitudes towards nature (student's knowledge about urban birds and their participation in conservation actions). We collected data on local biodiversity, socioeconomical status, and high school students' attitudes towards nature (15 schools, n = 175 students) in a large Latin American capital city. Structural equation modeling (SEM) was utilized to identify relationships among all variables. Socioeconomic characterization was assessed using levels of socio-materiality and school performance scores. Definitions of ecological complexity were based on bird species richness and vegetation density. Knowledge of urban birds was evaluated using two indicators: urban bird identification (recognition of names) and identification of the biogeographic origin of urban birds (native or exotic). Participation in conservation actions by students was assessed based on implementation scale and implementation frequency. According to our results, respondents' knowledge of birds was poor: 42% of students identified only two species (the domestic pigeon and the monk parakeet, both exotic). Only 26% of total students participated in conservation actions. SEM analysis revealed that socioeconomic status was positively associated with the ecological complexity of surrounding areas. In turn, ecological complexity showed a positive relationship with students' knowledge on urban birds. Finally, students' knowledge of urban birds showed a positive influence on conservation actions. Our findings suggest that, the improvement of students' knowledge about local biodiversity and ensuring equitable access to biodiversity could be an effective way to foster students' involvement in conservation actions, especially in neighborhoods of lower socioeconomic levels.

Design of the tertiary optical system for the Large Latin American Millimeter Array radio telescope

Design of the tertiary optical system for the Large Latin American Millimeter Array radio telescope

Modeling choice determinants for bicycle-bus integration in developing countries: Case study in Fortaleza, Brazil

In the context of first/last mile, the bicycle-transit intermodality could lessen accessibility problems of stations and stops, reducing the need for feeder services. Although extensively addressed in developed countries, bicycle-transit is less studied in Global South metropolises, where distinct usage patterns are observed. Thus, this research aimed to model the choice behavior of the low-income population for bicycle-transit integration in Fortaleza - Brazil, a large Latin American city with a deployed bike-sharing system focused mainly on bike-bus integration. A Stated Preference (SP) survey was conducted addressing socioeconomic and trip characteristics, as well as policy variables such as bicycle parking and cycleways/lanes. SP data allowed the estimation of nested and mixed logit models representing choice behavior, and sample segmentation was used to identify heterogeneity among different groups of individuals. The results show that investing in bicycle infrastructure could stimulate bike-bus integration in Fortaleza; however, their relative importance depends on the analyzed individual strata. Findings also indicate the influence of public and road safety issues, as well as gender, income, and trip characteristics such as purpose and access distance.

Predictors of Survival, Treatment Modalities, and Clinical Outcomes of Diffuse Large B-Cell Lymphoma in Patients Older Than 70 Years Still an Unmet Medical Need in 2024 Based on Real-World Evidence.

Diffuse large B-cell lymphoma (DLBCL) especially affects the older population. Old (≥60 years) and very old age (≥80 years) DLBCL patients often present high-risk molecular alterations, lower tolerability to conventional immunochemotherapy, and poor clinical outcomes. In this scenario, attenuated therapeutic strategies, such as the R-MiniCHOP and R-MiniCHOP of the elderly regimens, have emerged for this particularly fragile population. However, the responses, clinical outcomes, and toxicities of these regimens currently remain poorly understood, mainly because these individuals are not usually included in controlled clinical trials. This retrospective, observational, and single-center real-world study included 185 DLBCL, NOS patients older than 70 years treated at the largest oncology center in Latin America from 2009 to 2020. We aimed to assess the outcomes, determine survival predictors, and compare responses and toxicities between three different primary therapeutic strategies, including the conventional R-CHOP regimen and the attenuated R-MiniCHOP and R-MiniCHOP of the elderly protocols. The median age at diagnosis was 75 years (70-97 years), and 58.9% were female. Comorbidities were prevalent, including 19.5% with immobility, 28.1% with malnutrition, and 24.8% with polypharmacy. Advanced clinical stage was observed in 72.4%, 48.6% had bulky disease ≥7 cm, 63.2% had B-symptoms, and 67.0% presented intermediate-high/high-risk IPI. With a median follow-up of 6.3 years, the estimated 5-year OS and PFS were 50.2% and 44.6%, respectively. The R-MiniCHOP of the elderly regimen had a lower ORR (p = 0.040); however, patients in this group had higher rates of unfavorable clinical and laboratory findings, including hypoalbuminemia (p = 0.001), IPI ≥ 3 (p = 0.013), and NCCN-IPI ≥ 3 (p = 0.002). Although associated with higher rates of severe neutropenia (p = 0.003), the R-CHOP regimen promoted increased OS (p = 0.003) and PFS (p = 0.005) in comparison to the attenuated protocols. Additionally, age ≥ 75 years, high levels of LDH, B-symptoms, advanced clinical stage (III/IV), neutrophilia, and low lymphocyte/monocyte ratio were identified as poor prognostic factors in this cohort. In this large and real-life Latin American cohort, we demonstrated that patients with DLBCL, NOS older than 70 years still do not have satisfactory clinical outcomes in 2024, with half of cases not reaching 5 years of life expectancy after diagnosis. Although the conventional R-CHOP offers response and survival advantages over attenuated regimens, its myelotoxicity is not negligible. Therefore, the outcomes reported and the prognostic factors here identified may assist clinicians in the appropriate selection of therapeutic strategies adapted to the risk for old and very old DLBCL patients.

Association of PD-L1 expression with driver gene mutations and clinicopathological characteristics in non-small cell lung cancer: A real-world study of 10 441 patients.

Programmed death ligand-1 (PD-L1) expression is a well-known predictive biomarker of response to immune checkpoint blockade in non-small cell lung cancer (NSCLC). However, there is limited evidence of the relationship between PD-L1 expression, clinicopathological features, and their association with major driver mutations in NSCLC patients in Latin America. This retrospective study included patients from Argentina with advanced NSCLC, and centralized evaluation of PD-L1 expression concurrently with genomic alterations in the driver genes EGFR, ALK, ROS1, BRAF, and/or KRAS G12C in FFPE tissue samples. A total of 10 441 patients with advanced NSCLC were analyzed. Adenocarcinoma was the most frequent histological subtype (71.1%). PD-L1 expression was categorized as PD-L1 negative (45.1%), PD-L1 positive low-expression 1%-49% (32.3%), and PD-L1 positive high-expression ≥50% (22.6%). Notably, current smokers and males were more likely to have tumors with PD-L1 tumor proportion score (TPS) ≥50% and ≥ 80% expression, respectively (p < 0.001 and p = 0.013). Tumors with non-adenocarcinoma histology had a significantly higher median PD-L1 expression (p < 0.001). Additionally, PD-L1 in distant nodes was more likely ≥50% (OR 1.60 [95% CI: 1.14-2.25, p < 0.01]). In the multivariate analysis, EGFR-positive tumors were more commonly associated with PD-L1 low expression (OR 0.62 [95% CI: 0.51-0.75], p < 0.01), while ALK-positive tumors had a significant risk of being PD-L1 positive (OR 1.81 [95% CI: 1.30-2.52], p < 0.01). PD-L1 expression was associated with well-defined clinicopathological and genomic features. These findings provide a comprehensive view of the expression of PD-L1 in patients with advanced NSCLC in a large Latin American cohort.

Moving on: Exploring the implications of leader departure and incoming temporary leaders for collective turnover and unit performance.

While leader departures from work units frequently occur within organizations and are assumed to negatively impact unit functioning, the collective reaction to a leader departure event can vary across time. While a common expectation of leader departure models is that the incoming leader is permanent, it is unclear how unit-level reactions, such as collective turnover and unit performance, might change over time in response to a departure event when the departing leader is replaced with a temporary leader. We draw on context emergent turnover (CET) theory and literature on leader departures to develop and empirically test specific hypotheses exploring relationships among leader departures, collective turnover, and unit performance over time. In addition, we examine the extent to which these relationships are influenced by the temporary status of the incoming leader. Using discontinuous growth models, we examine a longitudinal data set from 324 units within a large Latin American operation of a global direct sales company (N = 3,082 performance periods). Findings indicate that, after a leader departs, there is an immediate increase in collective turnover and that unit performance decreases over time. Further, when the incoming leader is temporary, unit performance increases briefly, but the rate of performance drops over time. Overall, our research offers insights with regard to how leader departures impact unit outcomes, as well as how long such effects last. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Spatial analysis for prioritizing areas for urban renewal projects in the city of Cali in Colombia

Most traditional downtown areas in large Latin American cities are undergoing processes of physical deterioration and population decline; thus, alternative urban planning solutions are required to address these issues, including urban renewal as a means to enhance, valorize, improve, and integrate consolidated areas of the city through a change in patterns, with a view to promoting mixed-use development and prevent urban sprawl. This paper proposes a spatial analysis methodology for prioritizing areas for urban renewal projects (AEPRU) in the downtown area of Cali, Colombia, using indicators supported by current urban regulations and fieldwork in the selected study area. The results are reported through tables and thematic cartography produced with Geographic Information Systems (GIS) tools.

The street tree distribution across a streetscape reflects the social inequality of Latin American cities

Due to the ecosystem services they provide, street trees are fundamental for the quality of life and well-being of the urban human population. However, street trees are usually not equitably distributed across streetscapes, making some demographic groups most vulnerable to the consequences of a poorly managed street tree community. In this study, we evaluated if the socioeconomic characteristics of a large Latin American metropolis (wealth and density of older adults and children) are related to aspects describing characteristics of the street tree community (number of trees, beta diversity, canopy diameter, and proportion of native trees). Our street trees database is comprised of more than 250,000 trees and 559 species. Through a model selection approach, we observed that all socioeconomic characteristics relate to an aspect of the street tree community. The number of trees increased with wealth, but the highest densities of older adults were observed in regions with fewer trees. Canopy cover, conversely, decreased in wealthier neighborhoods and in regions with a higher density of children, while increasing with the density of older adults. Beta diversity of native trees also decreased with wealth. These results not only highlight the luxury effect across the streetscape but reflect the social inequality of Latin American cities: most people from both demographic groups live in regions with a less exuberant tree cover. Our approach can help identify the strengths and weaknesses regarding the plan and management of this street tree community, assisting in the definition of public policies and guidelines for a more sustainable and equitable urban landscape.

The Effects of a Short-Term Corporate Social Impact Activity on Employee Turnover: Field Experimental Evidence

Short-term corporate social impact activities, wherein employees participate in firm-sponsored prosocial initiatives, are becoming increasingly common. However, it remains unclear whether short-term social impact activities affect employee behavior in a manner of relevance to the firm. Theoretically, arguments could be made in favor of or against the likelihood that such short-term activities would increase firm-benefitting employee behavior. We utilized data from a randomized field experiment implemented at a large Latin American bank to examine whether a short-term social impact activity can be beneficial for firms, focusing on one important outcome: turnover. Newly hired employees were randomly assigned to a short-term social impact activity as part of the new employee onboarding process or not. Notably, we find causal evidence that a day-long, short-term engagement reduced employee turnover almost a year later. We explore potential mechanisms behind this effect and find that employees’ perceptions of organizational justice help to explain the effects of the intervention on turnover. We also explore heterogeneous treatment effects and find more substantial effects for male, rather than female, employees. This paper advances the literature on the implications of corporate social responsibility (CSR) practices by shedding light on the causal mechanisms through which a theoretically underexplored and practically relevant type of CSR activity can benefit organizations and their employees. This paper was accepted by Lamar Pierce, organizations. Funding: The authors acknowledge funding from NSF through the Learning the Earth with Artificial intelligence and Physics (LEAP) Science and Technology Center (STC) (Award #2019625). Supplemental Material: The data files are available at https://doi.org/10.1287/mnsc.2022.01517 .

Escape from the ‘lost decades?’ Governance challenges in Argentina, Brazil, Colombia, Mexico, and Venezuela

AbstractMuch of Latin America has experienced a renewed ‘lost decade’, failing to substantially expand quality of life since the late 2000s. While the outcomes of governance performance across the largest countries – including Brazil, Venezuela, Mexico, Colombia, and Argentina – have discrete causes, common themes like internal conflict, corruption, and overreliance on natural resources plague the entire region. Put more generally, the inability to turn democratic accountability into a state mechanism able to deliver economic growth and public goods in a sustainable manner is a liability affecting all five countries. To explore the difficulties that the large Latin American countries have faced in the twenty‐first century, this article examines results from the 2022 Berggruen Governance Index, and then presents three key issues facing the region: insufficient state capacity, flirtations with authoritarianism, and economic inequality and inflation. While the challenges remain substantial, increased regional integration may offer one way out of the predicament.

Caregivers on the move: Gender and socioeconomic status in the care mobility in Bogotá

The concept of mobility of care is relatively new and generating growing interest, because it allows a greater understanding of daily mobility and the differences in time use (TU) and unpaid workloads in the population. There is a large unexplored field of study in the relationships between the socioeconomic and gender characteristics of the population and care trips in large Latin American cities. This study uses the Mobility Survey for Bogotá − 2019 to characterizes travel for caregivers in the city, identifying trips made for care reasons, and then relating the analysis to variables of gender, age, socioeconomic status, occupation, and time and mode of transport used, in order to highlight and deepen the understanding of interdependence relationships between caregivers and care receivers. Results show that care work and care trips are carried out mostly by women, and we also find an unequal burden among caregivers and their socioeconomic conditions, with the lower strata population assuming a greater burden for care trips and time use when caring for others. Our findings contribute to the understanding of a phenomenon of growing importance and allow progress in the design and implementation of public policies towards a triple objective: transparency for care tasks and mobility, facilitation of their execution, and minimizing gender and socioeconomic status inequalities.

Genome-wide association study of Helicobacter pylori serological status in Latin American children.

Few genome-wide association studies (GWAS) on Helicobacter pylori infection susceptibility have been conducted for admixed populations from developing countries. Here, we performed a GWAS to identify genetic factors associated with H. pylori serostatus in a cohort of admixed children from a large Latin American urban center. A cross-sectional study involving 1161 children from 4 to 11 years old living in poor areas of Salvador, in northeastern Brazil. Logistic regression analysis was performed to detect associations between single-nucleotide variants (SNVs) and H. pylori seropositivity, assuming an additive genetic model. Enrichment analyses were conducted using the MAGMA v1.10 software. We found 22 SNVs to be suggestively associated (p < 10-5 ) with H. pylori seropositivity. The most suggestive SNV was the rs77955022 (p = 4.83e-07) located in an intronic region of EXOC3 at 5p15.33. The second most suggestively associated SNV was rs10914996 (p = 8.97e-07), located in an intergenic region at 1p34.3. Furthermore, we were able to replicate three SNVs (p < 0.05) in the Study of Health in Pomerania (SHIP) cohort: the rs2339212 and rs4795970, both located at 17q12 near TMEM132E, as well as the rs6595814, an intronic variant of FBN2 at 5q23.3. The enrichment analysis indicated the participation of genes and metabolic pathways related to the regulation of the digestive system and gastric acid secretion in the risk of seropositivity for H. pylori. Additional studies are required to validate these association findings in larger population samples and to get insight into the underlying physiological mechanisms.

FRI-282 - Validation of serum biomarker panels for early HCC detection: results from a large prospective European and Latin American multicenter study

FRI-282 - Validation of serum biomarker panels for early HCC detection: results from a large prospective European and Latin American multicenter study

Dental size variation in admixed Latin Americans: Effects of age, sex and genomic ancestry.

Dental size variation in modern humans has been assessed from regional to worldwide scales, especially under microevolutionary and forensic contexts. Despite this, populations of mixed continental ancestry such as contemporary Latin Americans remain unexplored. In the present study we investigated a large Latin American sample from Colombia (N = 804) and obtained buccolingual and mesiodistal diameters and three indices for maxillary and mandibular teeth (except third molars). We evaluated the correlation between 28 dental measurements (and three indices) with age, sex and genomic ancestry (estimated using genome-wide SNP data). In addition, we explored correlation patterns between dental measurements and the biological affinities, based on these measurements, between two Latin American samples (Colombians and Mexicans) and three putative parental populations: Central and South Native Americans, western Europeans and western Africans through PCA and DFA. Our results indicate that Latin Americans have high dental size diversity, overlapping the variation exhibited by the parental populations. Several dental dimensions and indices have significant correlations with sex and age. Western Europeans presented closer biological affinities with Colombians, and the European genomic ancestry exhibited the highest correlations with tooth size. Correlations between tooth measurements reveal distinct dental modules, as well as a higher integration of postcanine dentition. The effects on dental size of age, sex and genomic ancestry is of relevance for forensic, biohistorical and microevolutionary studies in Latin Americans.

Lacking time: A case study of student and faculty perceptions of academic workload in the COVID‐19 pandemic

AbstractBackgroundTo avoid the spread of COVID‐19, most engineering programs rapidly shifted to emergency online education, and prior research has associated online education with academic overload. Before the pandemic, engineering curricula were already packed with content and course assignments, so more studies should explore how the unprecedented conditions of remote learning affected the intensive academic workload of engineering programs.Purpose/HypothesisThis study addresses the following research question: How did the COVID‐19 pandemic affect the perceptions of engineering instructors and students regarding their academic workload? Thus, the main research objective is to explore the influence of COVID‐19 on the perceived academic workload, extrapolating lessons learned for engineering education settings.Design/MethodDuring 2020, we developed a single‐case study to understand academic workload in 22 engineering majors at a large Latin American university. We triangulated different sources of institutional and research‐focused evidence, including two instructor surveys (n = 110), two student surveys (n = 2218), two student focus groups (n = 18), and workload measurement surveys (n = 3131).ResultsBoth instructors and students experienced academic overload since the outbreak of the COVID‐19 pandemic. Throughout the first year, instructors became capable of accommodating course activities and assignments to students' particular circumstances. Regardless of these efforts, students continue perceiving academic overload, particularly affecting those who experience connectivity issues or frequent problems with their personal computer or tablet.ConclusionsFurther efforts are needed to support course planning and self‐regulated learning in engineering education. In these lines, lessons learned were captured and shared to inform engineering education research and practice beyond the COVID‐19 pandemic.

In-hospital and Post-discharge Status in COVID-19 Patients With Acute Respiratory Failure Supported With Extracorporeal Membrane Oxygenation.

Few data from Latin American centers on clinical outcomes in coronavirus disease 2019 (COVID-19) patients with acute respiratory distress syndrome who required extracorporeal membrane oxygenation (ECMO) are published. Moreover, clinical and functional status after hospital discharge remains poorly explored in these patients. We evaluated in-hospital outcomes of severe COVID-19 patients who received ECMO support in two Brazilian hospitals. In one-third of the survivors, post-acute COVID-19 syndrome (PACS), quality of life, anxiety, depression, and return to work were evaluated. Eighty-five patients were included and in-hospital mortality was 47%. Age >65 years (HR: 4.8; 95% confidence interval [CI]: 1.4-16.4), diabetes (HR: 6.0; 95% CI: 1.8-19.6), ECMO support duration (HR: 1.08; 95% CI: 1.05-1.12) and dialysis initiated after ECMO (HR: 3.4; 95% CI: 1.1-10.8) were independently associated with higher in-hospital mortality and mechanical ventilation (MV) duration before ECMO was not (HR: 1.18; 95% CI: 0.71-2.09). PACS-related symptoms were reported by two-thirds and half of patients at 30- and 90-days post-discharge, respectively. The median EQ-5D score was 0.85 (0.70-1.00) and 0.77 (0.66-1.00) at 30 and 90 days. Of the 15 responders, all previously working patients, except one, have returned to work at 90 days. In conclusion, in-hospital mortality in a large Latin American cohort was comparable to the Global extracorporeal life support organization registry.

Bicycle use in Latin American cities: changes over time by socio-economic position

IntroductionWe aimed to examine utilitarian bicycle use among adults from 18 large Latin American cities and its association with socio-economic position (education and income) between 2008 and 2018.MethodsData came from yearly cross-sectional surveys collected by the Development Bank of Latin America (CAF). A total of 77,765 survey respondents with complete data were used to estimate multilevel logistic regression models with city as random intercept and year as random slope.ResultsIndividuals with high education and high-income levels had lower odds of using a bicycle compared with participants with lower education and income levels. These associations, however, changed over time with the odds of bicycle use increasing for all groups, especially among individuals with the highest education and income levels.DiscussionOur results confirm the broadening appeal of bicycling across socio-economic positions in several Latin American cities and reinforce the importance of considering policies aimed at supporting and enhancing bicycle travel for all users.

Characterization of urban distribution networks with light electric freight vehicles

The massive incorporation of light electric freight vehicles (LEFV) in the last mile distribution has been identified as one of the alternatives that large Latin American cities shall include in their agenda for cleaner and more effective public policy in logistics operations. Thence, in this paper, arouting optimization model was used to evaluate the reduction in operational cost and GHG emissionswhen fueled cargo trucks or motorcycles are replacedbyLEFV (i.e.,e-trikes or e-bikes)in the last mile distribution in large Latin American cities. Results showed that for the case of a commercial area in Bogota, and two lines of business (i.e., parcel delivery and dry chain), the use of LEFV reduces more than 50% de operational cost and more than 95% the GHG emissions. These high reductions are due to the synergistic effect of switching from fuel to electricity and reducing the energy consumption of vehicles.

City features related to obesity in preschool children: a cross-sectional analysis of 159 cities in six Latin American countries

Childhood obesity is a rising global health problem. The rapid urbanization experienced in Latin America might impact childhood obesity through different pathways involving urban built and social features of cities. We aimed to evaluate the association between built and social environment features of cities and childhood obesity across countries and cities in Latin America. Cross-sectional analysis of data from 20,040 children aged 1-5 years living in 159 large cities in six Latin American countries. We used individual-level anthropometric data for excess weight (overweight or obesity) from health surveys that could be linked to city-level data. City and sub-city level exposures included the social environment (living conditions, service provision and educational attainment) and the built environment (fragmentation, isolation, presence of mass transit, population density, intersection density and percent greenness). Multi-level logistic models were used to explore associations between city features and excess weight, adjusting for age, sex, and head of household education. The overall prevalence of excess weight among preschool children was 8% but varied substantially between and within countries, ranging from 4% to 25%. Our analysis showed that 97% of the variability was between individuals within sub-city units and around 3% of the variance in z-scores of weight for height was explained by the city and sub-city levels. At the city-level, a higher distance between urban patches (isolation, per 1 SD increase) was associated with lower odds of excess weight (OR 0.90, 95% CI 0.82-0.99). Higher sub-city education was also associated with lower odds of excess weight, but better sub-city living conditions were associated with higher odds of excess weight. Built and social environment features are related to excess weight in preschool children. Our evidence from a wide range of large Latin American cities suggests that urban health interventions may be suitable alternatives towards attaining the goal of reducing excess weight early in the life course. The SALURBAL project (Salud Urbana en América Latina, Urban Health in Latin America) is funded by Wellcome [205177/Z/16/Z].