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This paper proposes a pseudo-birth-cohort approach to deal with a lack of longitudinal data to measure health inequities over time. Using Roemer's framework for inequality of opportunity, this study measures ex-ante and ex-post inequalities in malnutrition, a concept that spans both sides of the nutrition continuum. The total contribution of observed circumstances and the direct contribution of observed efforts to the variation of malnutrition are disentangled for people born between 1983 and 1988 in Mexico. Results indicate that inequality of opportunity has been persistent across this 30-year lifespan for that cohort. Some evidence suggests that a lack of opportunities has been transmitted from parents to children and that people's circumstances account for most of the explained variation in the double burden of malnutrition. However, stratifying the analysis by sex shows that efforts account for more of the explained variation of inequality of opportunity for women in their middle adulthood than for men in most of the outcomes analyzed.

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This research investigates how entrepreneurs perceive the hypothetical nature of technologies (based on situations that are often imagined or theoretical) as a foundation for entrepreneurial endeavors and how this perception influences the formation of business Opportunity Beliefs. Drawing on the Construal Level Theory, we explore the relationship between the perceived hypotheticality of technologies and Opportunity Beliefs. Two experimental studies are conducted to examine these relationships, with Study 1 (n = 177 entrepreneurs) focusing on the perception of innovative technologies as more distant or hypothetical, and Study 2 (n = 404 entrepreneurs) delving into how the perceived distance to technology influences Opportunity Beliefs. The results indicate that entrepreneurs view more innovative technologies as more hypothetical and that hypotheticality mediates the relationship between the perceived degree of innovation and Opportunity Beliefs. We find evidence that Entrepreneurs tend to view the feasibility and fit/alignment of business opportunities more favorably when they perceive the psychological distance (hypotheticality) of the opportunity as closer rather than more distant. However, the difference this difference is nonsignificant in how they evaluate the desirability of the opportunity in any psychological distance. These results provide insight into the cognitive processes of entrepreneurs and offer implications for understanding how entrepreneurs perceive and evaluate business opportunities.

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The Darwin-Bateman paradigm predicts that females enhance their fitness by being choosy and mating with high-quality males, while males should compete to mate with as many females as possible. In many species, males enhance their fitness by defending females and/or resources used by females. That is, males directly defend access to mating opportunities. However, paternity analyses have repeatedly shown that females in most species mate polyandrously, which contradicts traditional expectations that male defensive behaviours lead to monandry. Here, in an extensive meta-analysis, encompassing 109 species and 1026 effect sizes from across the animal kingdom, we tested if the occurrence of defensive behaviours modulates sexual selection on females and males. If so, we can illuminate the extent to which males really succeed in defending access to mating and fertilisation opportunities. We used four different indices of the opportunity for sexual selection that comprise pre-mating and/or post-mating episodes of selection. We found, for both sexes, that the occurrence of defensive behaviours does not modulate the potential strength of sexual selection. This implies that male defensive behaviours do not predict the true intensity of sexual selection. While the most extreme levels of sexual selection on males are in species with male defensive behaviours, which indicates that males do sometimes succeed in restricting females' re-mating ability (e.g. elephant seals, Mirounga leonina), estimates of the opportunity for sexual selection vary greatly across species, regardless of whether or not defensive behaviours occur. Indeed, widespread polyandry shows that females are usually not restricted by male defensive behaviours. In addition, our results indicate that post-mating episodes of selection, such as cryptic female choice and sperm competition, might be important factors modulating the opportunity for sexual selection. We discuss: (i) why male defensive behaviours fail to lower the opportunity for sexual selection among females or fail to elevate it for males; (ii) how post-mating events might influence sexual selection; and (iii) the role of females as active participants in sexual selection. We also highlight that inadequate data reporting in the literature prevented us from extracting effect sizes from many studies that had presumably collected the relevant data.

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Organisms use diverse strategies to thrive in varying habitats. While life history theory partly explains these relationships, the combined impact of resource availability and disturbance frequency on life form strategy evolution has received limited attention. We use Chamaecrista species, a legume plant lineage with a high diversity of plant life forms in the Neotropics, and employ ecological niche modeling and comparative phylogenetic methods to examine the correlated evolution of plant life forms and environmental niches. Chamaephytes and phanerophytes have optima in environments characterized by moderate water and nutrient availability coupled with infrequent fire disturbances. By contrast, annual plants thrive in environments with scarce water and nutrients, alongside frequent fire disturbances. Similarly, geophyte species also show increased resistance to frequent fire disturbances, although they thrive in resource-rich environments. Our findings shed light on the evolution of plant strategies along environmental gradients, highlighting that annuals and geophytes respond differently to high incidences of fire disturbances, with one enduring it as seeds in a resource-limited habitat and the other relying on reserves and root resprouting systems in resource-abundant habitats. Furthermore, it deepens our understanding of how organisms evolve associated with their habitats, emphasizing a constraint posed by low-resource and high-disturbance environments.

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We assessed the feasibility of obtaining parent-collected General Movement Assessment videos using the Baby Moves app. Among 261 participants from 4 Chicago NICUs, 70% submitted videos. Families living in higher areas of childhood opportunity used the app more than those from areas of lower opportunity.

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OBJECTIVE: To evaluate the effect of neighborhood-level characteristics on cardiorespiratory fitness (CRF) via peak oxygen consumption (VO2peak) for healthy pediatric patients. STUDY DESIGN: The institutional cardiopulmonary exercise testing (CPET) database was analyzed retrospectively. All patients aged ≤ 18 years without a diagnosis of cardiac disease and with a maximal effort CPET were included. Patients were divided into three self-identified racial categories: White, Black, and Latinx. The Child Opportunity Index (COI) 2.0 was used to analyze social determinants of health. CRF was evaluated based on COI quintiles and race. Assessment of the effect of COI on racial disparities in CRF was performed using ANCOVA. RESULTS: A total of 1753 CPETs met inclusion criteria. The mean VO2peak was 42.1 ± 9.8 mL/kg/min. The VO2peak increased from 39.1 ± 9.6 mL/kg/min for patients in the very low opportunity cohort to 43.9 ± 9.4 mL/kg/min for patients in the very high opportunity cohort. White patients had higher percent predicted VO2peak compared with both Black and Latinx patients (P < .01 for both comparisons). The racial differences in CRF were no longer significant when adjusting for COI. CONCLUSION: In a large pediatric cohort, COI was associated with CRF. Racial disparities in CRF are reduced when accounting for modifiable risk factors.

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OBJECTIVE: The objective of this study was to evaluate whether the children's neighborhood quality, as a measure of place-based social determinants of health, is associated with the odds of developmental delay and developmental performance up to the age of 4 years. STUDY DESIGN: Mothers of 5702 children from the Upstate KIDS Study, a longitudinal population-based cohort of children born from 2008 through 2010, provided questionnaire data and a subset of 573 children participated in a clinic visit. The Child Opportunity Index 2.0 was linked to home census tract at birth. Probable developmental delays were assessed by the Ages and Stages Questionnaire up to 7 times between 4 and 36 months, and developmental performance was assessed via the Battelle Developmental Inventory at the age of 4 years. RESULTS: In unadjusted models, higher neighborhood opportunity was protective against developmental delays and was associated with slightly higher development scores at age 4. After adjusting for family-level confounding variables, 10-point higher Child Opportunity Index (on a 100-point scale) remained associated with a lower odds of any developmental delay (OR = .966, 95% CI = .940-.992), and specifically delays in the personal-social domain (OR = .921, 95% CI = .886-.958), as well as better development performance in motor (B = 0.79, 95% CI = 0.11-1.48), personal-social (B = 0.64, 95% CI = 0.003-1.28), and adaptive (B = 0.69, 95% CI = 0.04-1.34) domains at age 4. CONCLUSIONS: Community-level opportunities are associated with some aspects of child development prior to school entry. Pediatric providers may find it helpful to use neighborhood quality as an indicator to inform targeted developmental screening.

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Progesterone receptors (PRs) are biomarkers used as prognostic and predictive factors in breast cancer, but they are still not used as therapeutic targets. We have proposed that the ratio between PR isoforms A and B (PRA and PRB) predicts antiprogestin responsiveness. The MIPRA trial confirmed the benefit of 200 mg mifepristone, administered to patients with tumors with a high PRA/PRB ratio, but dose-ranging has not been conducted. The aim of this study was to establish the plasma mifepristone levels of patients from the MIPRA trial, along with the resultant steroid profiles, and compare these with those observed in mifepristone-treated mice using therapeutic schemes able to induce the regression of experimental mammary carcinomas with high PRA/PRB ratios: 6 mg pellets implanted subcutaneously, or daily doses of 12 mg/kg body weight. The plasma levels of mifepristone and other 19 plasma steroids were measured by liquid chromatography-tandem mass spectometry. In mifepristone-treated mice, plasma levels were lower than those registered in mifepristone-treated patients (i.e. day 7 after treatment initiation, pellet-treated mice: 8.4 ± 3.9 ng/mL; mifepristone-treated patients: 300.3 ± 31.7 ng/mL (mean ± s.d.; P < 0.001)). The increase in corticoid related steroids observed in patients was not observed in mifepristone-treated mice. The increase in progesterone levels was the most significant side effect detected in mifepristone-treated mice after 14 or 21 days of treatment, probably due to an ovarian compensatory effect not observed in postmenopausal patients. We conclude that in future clinical trials using mifepristone, the possibility of lowering the standard daily dose of 200 mg should be considered.

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Objetivo: determinar si la anemia crónica es un factor de riesgo asociado a la muerte por choque hipovolémico en adultos peruanos. Métodos: estudio observacional, de casos y controles, basado en datos del Sistema Nacional de Defunciones del Ministerio de Salud peruano entre enero de 2021 a septiembre de 2022. La población estudiada fue de 281.456 adultos cuando se analizó según sexo, y 281.416 adultos cuando se dividió según grupo etario con una diferencia de 40 datos perdidos durante el procesamiento de la información. Se incluyó a pacientes con y sin anemia (variable independiente), cuyas causas de muerte inmediata fueron divididas en muertes por choque hipovolémico (variable dependiente) y muertes por otras causas inmediatas. Se realizó la prueba de Chi-cuadrado y el coeficiente V de Cramer, así como el análisis multivariado considerando variables como la edad y el sexo. Se consideró un valor de p significativo menor a 0,05 con un intervalo de confianza al 95%. Resultados: 1627 hombres fallecieron por choque hipovolémico de los cuales 18,20% tuvo anemia crónica (p<0,001). De 1540 mujeres fallecidas, 21,30% tuvo anemia crónica (p<0,001) y en ambos grupos (3167) el 19,70% tuvo anemia crónica (p<0,001). Con la prueba V de Cramer se halló una asociación positiva y baja entre las variables estudiadas (p<0,001). Los pacientes con anemia crónica tuvieron mayor probabilidad de morir por choque hipovolémico que los fallecidos sin anemia crónica, siendo mayor en adultos a partir de los 40 años, datos reafirmados en el modelo de regresión logística binaria. Conclusiones: la anemia crónica es una comorbilidad que supone un aumento del riesgo de muerte en pacientes con choque hipovolémico. Independientemente de la etiología del choque, el control y corrección de la anemia crónica podría tener un impacto en la reducción de la mortalidad de la hipovolemia aguda en adultos peruanos.

Objective: To determine if chronic anemia is a risk factor associated with death due to hypovolemic shock in Peruvian adults. Methods: Observational, case-control study, based on data from the National Death System of the Peruvian Ministry of Health between January 2021 and September 2022. Patients with and without anemia (independent variable) were included, whose causes of immediate death were divided into deaths due to hypovolemic shock (dependent variable) and deaths due to other immediate causes. The Chi-square test and Cramer's V coefficient were performed, as well as multivariate analysis considering variables such as age and sex. A significant p value of less than 0.05 with a 95% confidence interval was considered. Results: One thousand six hundred and twenty-seven men died from hypovolemic shock, of which 18.20% had chronic anemia (p<0.001). Of 1540 deceased women, 21.30% had chronic anemia (p<0.001) and in both groups (3167) 19.70% had chronic anemia (p<0.001). With Cramer's V test, a positive and low association was found between the variables studied (p<0.001). Patients with chronic anemia were more likely to die from hypovolemic shock than those who died without chronic anemia, and this was higher in adults over 40 years of age, data reaffirmed in the binary logistic regression model. Conclusions: Chronic anemia is a comorbidity that represents an increased risk of death in patients with hypovolemic shock. Regardless of the etiology of the shock, the control and correction of chronic anemia could have an impact on reducing mortality from acute hypovolemia in Peruvian adults.

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Population aging will increase the demand for long-term care services. Many countries, including Chile, have not implemented comprehensive responses to address these demands, relying on informal care. This article aims to estimate the economic value of caregiving in Chile, contributing to filling a gap in the literature and the policy debate. Economic value is estimated using replacement and opportunity cost approaches using two nationally representative databases: one survey on time use (to estimate hours of caregiving) and one on socioeconomic characterization (to identify caregivers and wages). Regressions for the determinants of caregiving effort and wages in the formal labor market are used to calculate the market value of caregiving time. Results show that the yearly value of caregiving ranges between US$266 million (when assuming a wage equal to the minimum wage for all caregivers) and US$4,946 million (when replacing all caregivers with nurses), i.e. between 0.11% and 1.95% of the country's gross domestic product. The analysis provides several estimations of the economic value of caregivers in Chile and, even considering these calculations can be underestimated, the results show the need to highlight and value the contribution of caregivers and implement policies to address the increase in long-term care needs in the country.

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Introduction: Coral-reef communities are considered one of the most biodiverse, but also most threatened, marine ecosystems, and the accelerating loss of habitat over the past decades warrants active intervention. Objective: The present study demonstrates the successful implementation of a low-impact restoration technique in three Central Mexican Pacific degraded coral communities, using a protocol based on natural fragmentation (''fragments of opportunity") of the branching coral Pocillopora spp., considered the most abundant and primary carbonate-producing coral species of the Eastern Tropical Pacific. Methods: The restoration program was implemented in two offshore and one inshore coraline areas. The relationships between seawater temperature and coral survival, growth, and attachment rate were assessed over one year, with 183 fragments monitored each month. Results: The mean coral growth rate was 3.3 ± 0.1 mm mo-1, with annual growth rates in length and width of 39.9 ± 14.2 and 36.5 ± 19.5 mm yr-1, respectively. Self-attachment efficiency was 78 % and the survival rate was high (84 %). The growth rate differed significantly among reefs. Conclusions: Upon monitoring directly fragmented corals over a year, growth rates were deemed high enough to merit active restoration in the region. However, our data show that structural and abiotic differences and seasonal variability must be considered overall in successful long-term coral community restoration initiatives in the eastern Pacific region.

Introducción: Las comunidades de arrecifes de coral se consideran uno de los ecosistemas marinos con mayor biodiversidad, pero también los más amenazados, y la pérdida acelerada de hábitat en las últimas décadas justifica la implementación de una intervención activa. Objetivo: El presente estudio demuestra la implementación exitosa de una técnica de restauración de bajo impacto basada en la fragmentación natural (''fragmentos de oportunidad") del coral ramificado Pocillopora spp., la cual es la especie coralina más abundante y principal productora de carbonato del Pacífico Oriental Tropical. Métodos: El programa de restauración se implementó en dos sitios lejos de la costa y un sitio cercano a la costa, con comunidades coralinas degradadas. Las relaciones entre la temperatura del agua de mar y la supervivencia, el crecimiento y la tasa de adhesión de los corales se evaluaron durante un año con 183 fragmentos monitoreados cada mes. Resultados: La tasa media de crecimiento coralino fue de 3.3 ± 0.1 mm mo-1, con tasas de crecimiento anual en largo y ancho de 39.9 ± 14.2 y 36.5 ± 19.5 mm año-1, respectivamente. La eficiencia de la auto-adherencia fue del 78 % y la tasa de supervivencia fue alta (84 %). La tasa de crecimiento difirió significativamente entre los arrecifes. Conclusiones: Al monitorear directamente los corales fragmentados durante un año, las tasas de crecimiento se consideraron lo suficientemente altas como para merecer una restauración activa en la región. Sin embargo, nuestros datos muestran que las diferencias estructurales y abióticas y la variabilidad estacional deben considerarse en general en las iniciativas exitosas de restauración de comunidades de coral a largo plazo en la región del Pacífico oriental.

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Introducción: En Chile, el Cáncer colorrectal (CC) abarca el 11,5% de todas las neoplasias malignas. La cirugía es la piedra angular del tratamiento del cáncer de colon, y en pacientes en etapa III, la quimioterapia adyuvante forma parte del tratamiento estándar. Materiales y Métodos: Estudio descriptivo retrospectivo transversal, de centro único, de pacientes con cáncer de colon en estadio III patológico. Objetivo principal de este estudio es conocer si, en pacientes con cáncer de colon etapa III, la quimioterapia adyuvante se entrega de manera oportuna. Resultados: En el período comprendido entre abril de 2016 y abril de 2021 se operaron 35 pacientes con cáncer de colon en estadio III patológico. Se realizó quimioterapia adyuvante en un 80%, y en siete pacientes durante las primeras ocho semanas poscirugía. La dehiscencia de anastomosis ocurrió en un 11,4%, aumentando la mediana de hospitalización en 2,2 veces. Discusión: En nuestro estudio, la adyuvancia en cáncer de colon etapa III se administró a un alto porcentaje de los pacientes (80%), pero observamos un retraso importante, ya que sólo en un 25% se inició el tratamiento durante las primeras 8 semanas poscirugía, lo cual puede ser explicado por múltiples factores, siendo la dehiscencia de anastomosis un punto importante a considerar. Conclusión: En estadio III de CC la adyuvancia puede verse retrasada por múltiples factores, lo que puede repercutir en la sobrevida de los pacientes, por lo tanto, conocer las causas de este retraso podría ayudar a instaurar nuevas estrategias, como la neoadyuvancia, para mejorar los resultados oncológicos.

Introduction: In Chile, colorectal cancer covers 11.5% of all malignant neoplasms. Surgery is the cor- nerstone of colon cancer treatment and in stage III patients adjuvant chemotherapy is part of standard treatment. Materials and Methods: A descriptive, retrospective, cross-sectional study, single center, of patients with pathological stage III colon cancer. Main objective of this study is to know if in patients with stage III colon cancer adjuvant chemotherapy is delivered in a timely manner. Results: Between April 2016 and April 2021, 35 patients with pathological stage III colon cancer were operated on. Adjuvant chemotherapy was performed in 80%, and in seven patient during the first eight weeks after surgery. Anastomotic dehiscence occurred in 11.4%, the median hospitalization increased by 2.2 times. Discussion: In this study, adjuvant stage III colon cancer was administered to a high percentage of patients (80%), but we observed a significant delay, since only 25% began treatment during the first 8 weeks post-surgery, which can be explained by multiple factors, with anastomotic dehiscence being an important point to consider. Conclusion: In stage III CC, adjuvant treatment can be delayed by multiple factors, which may affect patient survival; therefore, knowing the causes of this delay could help to establish new strategies, such as neoadjuvant therapy, to improve oncological results.

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Imminent predation risk affects mating behaviours in prey individuals in a multitude of ways that can theoretically impact the strength of sexual selection, as well as its operation on traits. However, empirical studies of the effects of imminent predation risk on sexual selection dynamics are still scarce. Here we explore how perceived predation affects: (1) the relationship between the opportunity for selection and the actual strength of selection on male traits; and (2) which traits contribute to male fitness and the shape of selection on these traits. We simulate two consecutive reproductive episodes, under control conditions and perceived predation risk using experimental populations of Trinidad guppies. The opportunity for selection is higher under predation risk compared to the control condition, but realised selection on traits remains unaffected. Pre- and postcopulatory traits follow complex patterns of nonlinear selection in both conditions. Differences in selection gradients deviate from predictions based on evolutionary and non-lethal effects of predation, the most notable being strong disruptive selection on courtship rate under predation risk. Our results demonstrate that sexual selection is sensitive to imminent predation risk perception and reinforce the notion that both trait-based and variance-based metrics should be employed for an informative quantification.

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BACKGROUND: Psychotic disorders contribute significantly to the global disease burden by causing disability, impaired quality of life, and higher mortality in affected people compared with the general population. In rural settings, where there is limited or no access to healthcare, individuals living with psychotic disorders often seek support from Community Health Workers (CHWs). However, little is known about what CHWs know about psychosis and how they manage such cases. This study aimed to explore the CHWs perception of psychosis and their experiences and beliefs about the factors that might enable or hinder care-taking for patients with psychosis in rural settings in Mozambique. METHODS: A qualitative study was conducted in rural districts of Maputo Province, a southern region of Mozambique, using six focus group discussions with participation of 79 CHWs. Thematic analysis was used informed by the Capabilities, Opportunities, Motivation and Behaviour framework (COM-B). RESULTS: Nine primary themes were identified. Overall, CHWs perceived psychosis as treatable medical conditions and held a positive attitude about being part of the care-taking process of patients with psychosis in rural settings. Partnerships with key-stakeholders such as traditional healers, health care workers, and families, were perceived by CHWs as enablers to improve access to care in rural areas. However, stigma, myths, and lack of competencies to treat people with psychosis were perceived by CHWs as barriers for appropriate care. CONCLUSION: CHWs, with adequate support, could play an important role in the care of patients with psychosis in rural settings, including identifying patients requiring care and referring them to appropriate healthcare professionals, and following up medicated patients with psychosis. Training of CHWs should consider inclusion of basic mental health care competencies.

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BACKGROUND: As a Neglected Tropical Disease associated with Latin America, Chagas Disease (CD) is little known in non-endemic territories of the Americas, Europe and Western Pacific, making its control challenging, with limited detection rates, healthcare access and consequent epidemiological silence. This is reinforced by its biomedical characteristics-it is usually asymptomatic-and the fact that it mostly affects people with low social and financial resources. Because CD is mainly a chronic infection, which principally causes a cardiomyopathy and can also cause a prothrombotic status, it increases the risk of contracting severe COVID-19. METHODS: In order to get an accurate picture of CD and COVID-19 overlapping and co-infection, this operational research draws on community-based experience and participative-action-research components. It was conducted during the Bolivian elections in Barcelona on a representative sample of that community. RESULTS: The results show that 55% of the people interviewed had already undergone a previous T. cruzi infection screening-among which 81% were diagnosed in Catalonia and 19% in Bolivia. The prevalence of T. cruzi infection was 18.3% (with 3.3% of discordant results), the SARS-CoV-2 22.3% and the coinfection rate, 6%. The benefits of an integrated approach for COVID-19 and CD were shown, since it only took an average of 25% of additional time per patient and undoubtedly empowered the patients about the co-infection, its detection and care. Finally, the rapid diagnostic test used for COVID-19 showed a sensitivity of 89.5%. CONCLUSIONS: This research addresses CD and its co-infection, through an innovative way, an opportunity of systematic integration, during the COVID-19 pandemic.

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Estrogen produces several beneficial effects in healthy neurological tissues and exhibits cardioprotective effects. Hormone therapy has been widely used to treat menopausal estrogen deficiency for more than 80 years. Despite high initial expectations of cardioprotective effects, there has been substantial distrust following important randomized clinical trials, such as the Women's Health Initiative. Subsequently, the timing of treatment in relation to the onset of menopause came under consideration and led to the proposal of the timing hypothesis, that early initial treatment is important, and benefits are lost as the timing since menopause becomes prolonged. Subsequent analyses of the Women's Health Initiative data, together with more recent data from randomized and observational trials, consistently show reductions in coronary heart disease and mortality in younger menopausal women. Regarding cognitive function, the timing hypothesis is consistent with observations from basic and animal studies. There is some clinical evidence to support the benefits of hormonal therapy in this context, though skepticism remains due to the paucity of clinical trials of substantial length in younger menopausal women. It is likely that the effects of estrogens on cognitive performance are due to rapid mechanisms, including mechanisms that influence Ca2+ homeostasis dynamics, provide protection in a hostile environment and reduce inflammatory signals from neural tissues. In the future, inflammatory profiles accounting for early signs of pathological inflammation might help identify the 'window of opportunity' to use estrogen therapy for successful cognitive protection.

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With the rapid development of industrialization and urbanization, returning-home entrepreneurship has received increasing attention from social and academic circles. This paper adopted the method of descriptive statistics to analyze the current situation, and the process by which entrepreneurs in the returning-home entrepreneurship ecosystem participate in the development of entrepreneurial opportunities from two dimensions: resource acquisition and institutional support. This research adopted the method of social network analysis to explore the mechanism of opportunity development of each subject of the returning-home entrepreneurship ecosystem. The results showed that during the opportunity development of returning-home entrepreneurship, all the subjects in the returning-home entrepreneurship ecosystem participated with their own resources and capabilities and jointly promoted the development of opportunities. During the development of these opportunities, each subject in the returning-home entrepreneurship ecosystem participated in different ways and with different emphases. This paper enriched the integration research of returning-home entrepreneurship theory and innovation ecosystem theory, and provided a reference for realizing rural revitalization and promoting regional economic development.

Com o rápido desenvolvimento da industrialização e da urbanização, o empreendedorismo voltando para cidade natal tem recebido cada vez mais atenção dos círculos sociais e acadêmicos. Nesse texto, adotando um método de análise estatística descritiva, analisamos a situação atual e o processo pelo qual os empreendedores do ecossistema de empreendedorismo voltando para cidade natal participam do desenvolvimento de oportunidades empreendedoras nas duas dimensões: aquisição de recursos e apoio institucional. E adotando o método de análise de rede social, exploramos o mecanismo de desenvolvimento de oportunidades de cada sujeito do ecossistema de empreendedorismo de retorno de cidade natal. Os resultados mostram que durante o desenvolvimento das oportunidades de empreendedorismo de retorno de cidade natal, todos os sujeitos do ecossistema de empreendedorismo de retorno de cidade natal participaram com seus próprios recursos e capacidades e promoveram conjuntamente o desenvolvimento de oportunidades. Durante o desenvolvimento dessas oportunidades, cada sujeito do ecossistema do empreendedorismo de retorno de cidade natal participou de diferentes formas e com diferentes ênfases. Este texto ajuda a enriquecer a pesquisa de integração da teoria do empreendedorismo de retorno de cidade natal e da teoria do ecossistema de inovação, e além disso fornece uma referência para realizar a revitalização rural e promover o desenvolvimento econômico regional.

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Aiming to assist the environmental sustainability of the Brazilian Amazonian agriculture, this article developed an eco-efficiency index, indicating the possible limits to maximize economic and environmental objectives, taking into account the best practices in the municipalities of the region. Shadow prices of degraded areas and forest preservation were also estimated using data envelopment analysis with directional distance functions. The results indicate that, on average, the analyzed municipalities are able to expand the production and the forest areas by 38% and reduce degraded areas and their inputs in the same proportion. The shadow prices allowed the estimation of the annual opportunity cost of the degraded areas and the preservation of the forest on the farms. The first, US$ 3,131,571, represented 0.04% of the annual output value, indicating that the internalization of that cost should be a low burden for the eco-efficient producer. The second, the total cost of preserving 80% of the area of property, represented US$ 120,890,662 or 1.7% of the annual income of the biome producers studied. Therefore, the main conclusion of this work is that the internalization of negative and positive externalities of agricultural production in the Amazonian biome does not make agricultural production economically unfeasible in the region. In addition, the reimbursement of damages avoided by carbon sequestration, through the Clean Development Mechanism (CDM) established by the Kyoto Conference, should further increase the economic and environmental sustainability of agriculture in the area.

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There is great heterogeneity in parasite communities among hosts, understanding the nature and drivers of such variations is still a great scientific quest. Here, we analyse the variation in parasite communities by addressing the following questions: (i) What is the beta-diversity component (nestedness or turnover) that most contributes to beta diversity in parasite communities among anuran species? (ii) Does the beta diversity of parasite communities follow a non-random pattern? (iii) Is the dissimilarity in composition of parasite communities related to the phylogenetic or functional dissimilarity among hosts? We found that turnover in parasite assemblages was the main component of beta diversity, but the variation observed both in the total beta diversity and in its components did not differ from the respective null models. The dissimilarity among parasite communities was not related to the phylogenetic species variability or functional dissimilarity among anuran species for most localities. In short, our findings may indicate a process of resource tracking by the parasite species, in which the resource may not necessarily be conserved phylogenetically in their hosts.

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