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Estuarine mangroves are often considered nurseries for the Atlantic Goliath grouper juveniles. Yet, the contributions of different estuarine primary producers and habitats as sources of organic matter during early ontogenetic development remain unclear. Given the species' critically endangered status and protection in Brazil, obtaining biological samples from recently settled recruits in estuaries is challenging. In this study, we leveraged a local partnership with fishers and used stable isotope (C and N) profiles from the eye lenses of stranded individuals or incidentally caught by fishery to reconstruct the trophic and habitat changes of small juveniles. The eye lens grows by the apposition of protein-rich layers. Once these layers are formed, they become inert, allowing to make inferences on the trophic ecology and habitat use along the development of the individual until its capture. We used correlations between fish size and the entire eye lens size, along with estuarine baselines, to reconstruct the fish size and trophic positions for each of the lens layers obtained. We then used dominant primary producers and basal sources from mangrove sheltered, exposed estuarine and marine habitats to construct an ontogenetic model of trophic and habitat support changes since maternal origins. Our model revealed marine support before the juveniles reached 25 mm (standard length), followed by a rapid increase in reliance on mangrove sheltered sources, coinciding with the expected size at settlement. After reaching 60 mm, individuals began to show variability. Some remained primarily supported by the mangrove sheltered area, while others shifted to rely more on the exposed estuarine area around 150 mm. Our findings indicate that while mangroves are critical for settlement, as Goliath grouper juveniles grow, they can utilize organic matter produced throughout the estuary. This underscores the need for conservation strategies that focus on seascape connectivity, as protecting just one discrete habitat may not be sufficient to preserve this endangered species and safeguard its ecosystem functions.

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There are various climate policies to decarbonize the energy matrix of a country. In the case of Chile, a carbon tax of 5 USD/tCO2 was initially implemented, and later, a schedule was established for the phase-out of coal-fired thermoelectric plants, all the above in the absence of subsidies for non-conventional renewable energy (NCRE). This study uses a computable general equilibrium (CGE) model and microsimulations to assess the contribution of current climate policies and other more demanding scenarios that accelerate the decarbonization of the Chilean energy matrix, considering economic, environmental, and distributional impacts. Specifically, carbon taxes are simulated with and without complementary climate policies (phase-out of coal-fired power plants and NCRE subsidies). The results show that the scenarios that combine the three climate policies generate a greater decrease in greenhouse gas emissions (40.4% âˆ¼ 57.5%). Besides, the drop in GDP is more pronounced when coal-fired thermoelectric plants phase out (0.3% additional), and NCRE subsidies contribute to moderately reducing emissions. However, NCRE subsidies reduce the negative effect on households' expenditure and income, especially in the poorest quintile. Finally, microsimulations show marginal changes in income distribution and an increase of up to 0.4 percentage points in the poverty rate.

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Decades of government subsidies for LPG and electricity have facilitated near-universal clean cooking access and use in Ecuador, placing the nation ahead of most other peer low- and middle-income countries. The widespread socio-economic impacts of the COVID-19 pandemic has threatened the resilience of clean cooking systems globally, including by altering households' ability to purchase clean fuels and policymakers' considerations about continuing subsidy programs. As such, assessing the resilience of clean cooking in Ecuador during the pandemic can offer important lessons for the international community, especially other countries looking to ensure resilient transitions to clean cooking. We study household energy use patterns using interviews, newspaper reports, government data on household electricity and LPG consumption, and household surveys [N = 200 across two rounds]. The LPG and electricity distribution systems experienced occasional disruptions to cylinder refill delivery and meter reading processes, respectively, which were associated with pandemic-related mobility restrictions. However, for the most part, supply and distribution activities by private and public companies continued without fundamental change. Survey participants reported increases in unemployment and reductions in household income as well as increased use of polluting biomass as a secondary fuel. Ecuador's LPG and electricity distribution systems were resilient throughout the pandemic, with only minimal interruption of the widespread provision of low-cost clean cooking fuels. Our findings inform the global audience concerned about the resilience of clean household energy use on the potential for clean fuel subsidies to facilitate continued clean cooking even during the COVID-19 pandemic.

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Allochthonous resource fluxes mediated by organisms crossing ecosystem boundaries may be essential for supporting the structure and function of resource-limited environments, such as tropical islands and surrounding coral reefs. However, invasive species, such as black rats, thrive on tropical islands and disrupt the natural pathways of nutrient subsidies by reducing seabird colonies. Here, we used stable isotopes of nitrogen and carbon to examine the role of seabirds in subsidizing the terrestrial food webs and adjacent coral reefs in the Abrolhos Archipelago, Southwest Atlantic Ocean. By sampling invasive rats and multiple ecosystem compartments (soil, plants, grasshoppers, tarantulas, and lizards) within and outside seabird colonies, we showed that seabird subsidies led to an overall enrichment in 15 N across the food web on islands. However, contrary to other studies, δ15 N values were consistently lower within the seabird colonies, suggesting that a higher seabird presence might produce a localized depletion in 15 N in small islands influenced by seabirds. In contrast, the nitrogen content (%N) in plants and soils was higher inside the colonies, corresponding to a higher effect of seabirds at the base of the trophic web. Among consumers, lizards and invasive rats seemed to obtain allochthonous resources from subsidized terrestrial organisms outside the colony. Inside the colony, however, they showed a more direct consumption of marine matter, suggesting that subsidies benefit these native and invasive animals both directly and indirectly. Nonetheless, in coral reefs, scleractinian corals assimilated seabird-derived nitrogen only around the two smaller and lower-elevation islands, as demonstrated by the substantially higher δ15 N values in relation to the reference areas. This provides evidence that island morphology may influence the incorporation of seabird nutrients in coral reefs around rat-invaded islands, likely because guano lixiviation toward seawater is facilitated in small and low-elevation terrains. Overall, these results showed that seabirds affected small islands across all trophic levels within and outside colonies and that these effects spread outward to coral reefs, evidencing resiliency of seabird subsidies even within a rat-invaded archipelago. Because rats are consumers of seabird chicks and eggs, however, rat eradication could potentially benefit the terrestrial and nearshore ecosystems through increased subsides carried by seabirds.

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RESUMO O presente artigo avaliou o fim dos benefícios fiscais dados aos agrotóxicos a partir dos microdados do Censo agropecuário de 2017. Realizou-se um estudo descritivo explorando duas variáveis pesquisadas: a despesa com agrotóxicos e o lucro obtido com a atividade agropecuária. Foram traçados cenários de aplicação de alíquotas de tributação dos agrotóxicos e os seus respectivos aumentos de preços, o que possibilitou avaliar os impactos diretos na lucratividade dos produtores. O cenário de tributação que gere um aumento de 15% nos preços dos agrotóxicos reduziria a lucratividade em cerca de 5,1% em 2017 (R$ 4,8 bilhões). Contudo, os maiores impactados seriam os produtores de commodities, com uma redução média de 9,6% na lucratividade. Discutiram-se esses resultados à luz de dois prismas: o impacto na renda do produtor e possíveis consequências no aumento de preços da cesta básica; e a capacidade da função extrafiscal do imposto em regular o uso dos agrotóxicos e redirecionar possíveis mudanças na tomada de decisão sobre os métodos de controle de pragas mais sustentáveis. Concluiu-se que há necessidade de harmonizar regras fiscais à uma política pública mais equilibrada no âmbito do setor agropecuário que garantisse a defesa da saúde da população e a sustentabilidade ambiental.

ABSTRACT This paper assesses the end of the tax incentives given to pesticides, based on the constitutionality analysis lawsuit (ADI 5553) that will be judged by the Supreme Court, which discusses the exemptions of ICMS and IPI on these products. Based on the last Brazilian Census Survey we evaluate the tax incidence of ICMS and IPI on agricultural expenditure and profitability of the agricultural establishment in some diferent scenarios. A 15% increase in pesticide prices would have an impact on costs and profitability of approximately R$ 4 and R$ 6.8 billion (-7%), respectively. This represents a value of almost R$ 10 billion less than calculated by a similar study released by the Sindicato Nacional da Indústria da Defesa Vegetal (Sindiveg) for a scenario of equivalent price increase. We discussed not only the impact results in income of the producer, but also the capacity of the extrafiscal function of the tax to regulate the use of pesticides and redirect possible changes in decision making on pest control methods, enabling the transition to a more sustainable and healthy agriculture. Finally, we conclude that, regardless of the outcome of the judgment of ADI 5553, the problem of negative externalities resulting from the use of pesticides does not end with the end of fiscal incentives to them, as they depend on the formulation of a more balanced public policy within the scope of the agricultural sector that would guarantee the defense of the population's health and environmental sustainability.

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Resource acquisition and allocation impacts individual fitness. Using pellet analysis of breeding adults and stable isotopes of carbon and nitrogen of down feathers of Kelp Gull (Larus dominicanus) nestlings, we evaluated the relationship between urban refuse (beef and chicken) and natural food (fish) consumption of individual females during the pre-incubation period, with fecundity and young nesting's success in the Río de la Plata Estuary in Uruguay. Assimilated urban refuse positively correlated with egg weight and negatively with young nestling's success. This suggests a possible impact of urban refuse foraged by females during the pre-incubation period on their immediate fecundity (positively) and young nestling's survival (negatively). Differences between studies at the individual and colony levels are also discussed in light of an "ecological fallacy" of interpretation and we thus argue for the need of additional research to evaluate this relationship further, considering potential confounding factors.

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State Film Incentives (SFIs) are a recent and popular economic development incentive. I study these through case studies of two prominent SFIs: those in Louisiana and New Mexico, using the Abadie et al. (2010) synthetic control case study method. This allows me to estimate the effect of SFIs relative to the "business-as-usual": what would have happened without SFIs. I estimate the effects of these SFIs on filming location, using databases from IMDb and Studio System, and on business establishments, and employment in the motion picture production industry, using the Quarterly Census of Employment and Wages. My results show increases in feature films, but not TV series filming, employment, or business establishments. This suggests that while there are some benefits to these incentives, their ability, under favorable circumstances, to develop a local film industry is very limited.

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Communities are shaped by a variety of ecological and environmental processes, each acting at different spatial scales. Seminal research on rocky shores highlighted the effects of consumers as local determinants of primary productivity and community assembly. However, it is now clear that the species interactions shaping communities at local scales are themselves regulated by large-scale oceanographic processes that generate regional variation in resource availability. Upwelling events deliver nutrient-rich water to coastal ecosystems, influencing primary productivity and algae-herbivore interactions. Despite the potential for upwelling to alter top-down control by herbivores, we know relatively little about the coupling between oceanographic processes and herbivory on tropical rocky shores, where herbivore effects on producers are considered to be strong and nutrient levels are considered to be limiting. By replicating seasonal molluscan herbivore exclusion experiments across three regions exposed to varying intensity of seasonal upwelling, separated by hundreds of kilometers along Panama's Pacific coast, we examine large-scale environmental determinants of consumer effects and community structure on tropical rocky shores. At sites experiencing seasonal upwelling, grazers strongly limited macroalgal cover when upwelling was absent, leading to dominance by crustose algae. As nutrients increased and surface water cooled during upwelling events, increases in primary productivity temporarily weakened herbivory, allowing foliose, turf and filamentous algae to replace crusts. Meanwhile, grazer effects were persistently strong at sites without seasonal upwelling. Our results confirm that herbivores are key determinants of tropical algal cover, and that the mollusk grazing guild can control initial stages of macroalgal succession. However, our focus on regional oceanographic conditions revealed that bottom-up processes regulate top-down control on tropical shorelines. This study expands on the extensive body of work highlighting the influence of upwelling on local ecological processes by demonstrating that nutrient subsidies delivered by upwelling events can weaken herbivory in tropical rocky shores.

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BACKGROUND: Cancer research is a prominent theme on national and international development agendas. In many developed countries, funding for this area comes mainly from government sources. This article analyzes government funding of cancer research in Brazil, identifying the main funding instruments and examining the regional distribution of resources, research project and researcher profiles. METHODS: Exploratory study of government funding of cancer research in Brazil between 2007 and 2016. The primary data were federal and state funding agencies. RESULTS: A total of 8565 research awards were identified for the period 2007-2016. Amounting to almost US$489 million, these awards were linked to 7622 research projects and 3068 researchers. The proportion of grants awarded to women was slightly higher. It is noteworthy that just 3% of researchers received 20 % of the grants. The multiple-grant history of individual researchers seemed to be a conditioning factor for obtaining new grants/fellowships. Funding was highly concentrated in the Southeast region, accounting for 84.4 % of total awards. There was a positive correlation between number of awards and amount awarded. The most frequently studied cancers were breast (11.8 %), head and neck (9.0 %) and skin cancer (5.3 %). Studies that did not specify the type of cancer accounted for 36.8 % of grants and 45.1 % of funding. CONCLUSION: The findings show a fall in the share of cancer research funding in the three largest funders. Cuts in government spending triggered by the country's political and economic crisis, highlight the vulnerability of science and technology. Greater transparency through access to information on funding, researcher, and research profiles is key to obtaining a better understanding the cancer research funding landscape in Brazil and reducing regional inequalities. POLICY SUMMARY: A more centralized management of public cancer research funding and constant investment and monitoring is needed to ensure the effective implementation of funding policy.

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Venezuela ha pasado a ser un país asimétrico, con grandes desigualdades y la inseguridad alimentaria familiar constituye quizás el problema nutricional más importante. En 1996, se comenzó a implementar la "Agenda Venezuela", la cual tiene un componente de protección social, que incluye 14 programas, para compensar a los grupos de población más desfavorecidos por las medidas económicas. Objetivo. Describir y analizar las fortalezas y debilidades de los programas de la Agenda, más vinculados con la situación nutricional. Materiales y métodos. Se basó en el análisis de informes presentados por los organismos ejecutores, de una encuesta de opinión realizada en Caracas, además de entrevistas a coordinadores de los programas. Se examinaron los programas: alimentos estratégicos, subsidio familiar, alimentación escolar, merienda y comedores escolares, hogares y multihogares de cuidado diario. Resultados. Las debilidades más comunes son: deficiente evaluación y apoyo educativo, escasa cobertura, solapamiento de beneficiarios, problemas de tipo logístico y presupuestario. A pesar de la fuerte inversión de recursos, el déficit nutricional en menores de seis años presenta una tendencia ascendente, lo cual reitera que los problemas nutricionales son multicausales y requieren de políticas sociales integrada, estables en el tiempo y focalizadas en los grupos más vulnerables. Conclusiones. Esta situación obliga a replantearse los programas en función a la pertinencia, factibilidad, costo-eficiencia e impacto y ha reiterado, la necesidad de un proceso de descentralización para otorgar más responsabilidad y poder de decisión a los gobiernos estatales, municipales y a la comunidad organizada y lograr un mayor impacto en la población objetivo y su contexto(AU)

Venezuela has become an asymmetric country, with great inequalities and family food insecurity is perhaps the most important nutritional problem. In 1996, the "Venezuela Agenda" began to be implemented, which has a social protection component, which includes 14 programs, to compensate the most disadvantaged population groups for economic measures. Objective. Describe and analyze the strengths and weaknesses of the Agenda programs, more linked to the nutritional situation. Materials and methods. It was based on the analysis of reports submitted by the executing agencies, an opinion poll conducted in Caracas, as well as interviews with program coordinators. The programs were examined: strategic food, family subsidy, school feeding, snack and school canteens, daily care homes and multi-homes. Results. The most common weaknesses are poor evaluation and educational support, poor coverage, overlapping beneficiaries, logistical and budgetary problems. Despite the strong investment of resources, the nutritional deficit in children under six years of age shows an upward trend, which reiterates that nutritional problems have multiple causes and require integrated social policies, stable over time and focused on the most vulnerable groups. Conclusions. This situation forces us to reconsider the programs based on their relevance, feasibility, cost-efficiency and impact and has reiterated the need for a decentralization process to grant more responsibility and decision-making power to state and municipal governments and to the organized community and achieve a greater impact on the target population and its context(AU)

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This paper evaluates the health effects of a large-scale subsidizing program of prescription drugs introduced in Brazil, the Aqui Tem Farmácia Popular program (ATFP). We exploit features of the program to identify its effects on mortality and hospitalization rates by diabetes for individuals aged 40 years or more. We find weak evidence for a decline in mortality, but a robust reduction in hospitalization rates. According to our preferred specification, an additional ATFP pharmacy per 100,000 inhabitants is associated with a decrease in hospitalization rates by diabetes of 8.2, which corresponds to 3.6% of its baseline rate. Effects are larger for Type II diabetes in comparison to Type I, and among patients with relatively lower socioeconomic status. Overall, the results are consistent with insulin-dependent patients being relatively less responsive to subsidies because of higher immediate life-threatening risks; and with lower-SES individuals being more responsive because of liquidity constraints. These results support the view that the optimal design of health systems and cost-sharing mechanisms should take into account equity concerns, heterogeneous impacts by health condition, and their potential offsetting effects on the utilization of downstream health services.

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Human waste is a global concern, and volumes are growing rapidly. For opportunistic species, like many birds, urban waste offers alternative food which in turn may lead to plastic ingestion with potential negative effects. We assessed the incidence of plastics and other marine debris in breeding Kelp Gull (Larus dominicanus) diet at nine colonies located along ~2400 km of coastline from southern Buenos Aires to southern Chubut, Argentina, using regurgitated pellets (n = 2355) and chick stomach content samples (n = 588). Plastics were recorded at all colonies, and incidence varied between 0.0 and 16.2% in adult pellets and 0.0-12.5% in chick stomach content samples, depending on the colony, breeding stage and year. Contrary to our expectation, incidence of debris including plastics in Kelp Gull diet was relatively low despite its opportunistic feeding habits and widespread use of refuse dumps, even at colonies located close (<10 km) to these anthropogenic food subsidies.

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Abstract INTRODUCTION: This study investigated the role of early public research funding regarding the COVID-19 pandemic in Brazil. METHODS: We examined the budget for research projects relating to the number of cases and deaths and the relationship between each federal unit, gross domestic product (GDP) per capita, and the national GDP per capita. RESULTS: Using data from the websites of official funding agencies and the Brazilian government, we found that, in the first four months since the first case in Wuhan, China (December 31, 2019), around US$ 38.3 million were directed to public funding for scientific investigations against the COVID-19 pandemic. However, only 11 out of 27 federal units provided funding during the initial stages of the outbreak, and those that did provide financing were not necessarily the units having the most inhabitants, highest GDP, or the greatest number of cases. The areas of research interest were also identified in the funding documents; the most common topic was "diagnosis" and the least common was "equipment for treatment." CONCLUSIONS: Brazilian researchers had access to funding opportunities for projects against COVID-19. However, strategies to minimize the economic impacts of COVID-19 are crucial in mitigating or avoiding substantial financial and social shortcomings, particularly in terms of an emerging market such as Brazil.

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After more than three decades of access to low-cost liquefied petroleum gas (LPG) financed by large direct government subsidies, more than 90% of Ecuadorian households cook primarily with LPG. Due to the large fiscal burden of the LPG subsidy, increases in electricity from hydropower, and other sociopolitical factors, the Government of Ecuador launched a major induction stove program (PEC) to reduce the demand for LPG. We assess the effects of the LPG subsidies and PEC using government records, interviews, academic literature, newspaper reports, household surveys, and focus groups. Household surveys, conducted in rural, northern Ecuadorian households (n=383), characterized cooking patterns and fuel access. Focus groups (n=6) were carried out with a subset of surveyed households to better characterize survey findings. The LPG subsidy was developed as part of broad social support reforms in the early 1970s, without specific aims to reduce the health impacts of household air pollution from woodfuel or provide economic benefits as part of the transition to a clean cooking fuel. Nonetheless, the subsidy has resulted in nearly all Ecuadorian households cooking primarily with LPG. PEC has generated the sale of 740,000 induction stoves since its inception in 2014, short of the goal of 3.5 million. Among the rural households surveyed, LPG use, acceptance, and satisfaction was high, however, more than three-quarters of those surveyed reported weekly woodfuel use. Induction stove ownership (17%) and use as a primary cooking fuel (1%) was low among the rural households surveyed; furthermore, households owning induction stoves reported very low satisfaction with the stoves. Here we show that nationally-representative surveys reporting only "primary cooking fuef" use may underestimate solid fuel use as a supplemental household cooking energy, particularly in rural areas where fuel availability issues play a stronger role in decisions about what fuels to use.

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Coastal marine upwelling famously supports elevated levels of pelagic biological production, but can also subsidize production in inshore habitats via pelagic-benthic coupling. Consumers inhabiting macroalgae-dominated rocky reef habitats are often considered to be members of a food web fuelled by energy derived from benthic primary production; conversely, they may also be subsidized by materials transported from pelagic habitats. Here, we used stable isotopes (δ13 C, δ15 N) to examine the relative contribution of pelagic and benthic materials to an ecologically and economically important benthivorous fish assemblage inhabiting subtidal macroalgae-dominated reefs along ~1,000 km of the northern Chilean coast where coastal upwelling is active. Fish were isotopically most similar to the pelagic pathway and Bayesian mixing models indicated that production of benthivorous fish was dominated (median 98%, range 69-99%) by pelagic-derived C and N. Although the mechanism by which these materials enter the benthic food web remains unknown, our results clearly highlight the importance of pelagic-benthic coupling in the region. The scale of this subsidy has substantial implications for our basic understanding of ecosystem functioning and the management of nearshore habitats in northern Chile and other upwelling zones worldwide.

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The Instituto Mexicano del Seguro Social (IMSS) through the Coordinación de Investigación en Salud (Health Research Council) has promoted a strong link between the generation of scientific knowledge and the clinical care through the program Redes Institucionales de Investigación (Institutional Research Network Program), whose main aim is to promote and generate collaborative research between clinical, basic, epidemiologic, educational, economic and health services researchers, seeking direct benefits for patients, as well as to generate a positive impact on institutional processes. All of these research lines have focused on high-priority health issues in Mexico. The IMSS internal structure, as well as the sufficient health services coverage, allows the integration of researchers at the three levels of health care into these networks. A few years after their creation, these networks have already generated significant results, and these are currently applied in the institutional regulations in diseases that represent a high burden to health care. Two examples are the National Health Care Program for Patients with Acute Myocardial Infarction "Código Infarto", and the Early Detection Program on Chronic Kidney Disease; another result is the generation of multiple scientific publications, and the promotion of training of human resources in research from the same members of our Research Networks. There is no doubt that the Coordinación de Investigación en Salud advances steadily implementing the translational research, which will keep being fruitful to the benefit of our patients, and of our own institution.

El Instituto Mexicano del Seguro Social (IMSS), a través de la Coordinación de Investigación en Salud, ha promovido el vínculo entre la generación de conocimiento científico y la actividad asistencial mediante el programa de Redes Institucionales de Investigación, cuyo objetivo principal es la promoción y generación de trabajo de investigación colaborativo entre investigadores del área clínica, básica, epidemiológica, educativa y en economía y sistemas de salud, buscando siempre obtener productos que tengan aplicación directa sobre los pacientes y generen un impacto positivo en los procesos institucionales. Todas las líneas de investigación se enfocan en los temas prioritarios de salud de México. La estructura interna del IMSS y la vasta cobertura de servicios que ofrece permiten incluir en estas redes a personal de los tres niveles de atención médica. A pocos años de su creación, estas redes han generado importantes resultados que se aplican en la normativa institucional en enfermedades con alta carga asistencial y económica; por ejemplo, el programa "Código Infarto" y el Programa de Detección Temprana de Enfermedad Renal Crónica; otro resultado son las múltiples publicaciones científicas y la promoción de la formación de recursos humanos en investigación de los mismos integrantes de nuestras redes de investigación. Sin duda, la Coordinación de Investigación en Salud avanza a grandes pasos en la implementación cada vez más sólida de la investigación traslacional, que seguirá dando frutos en beneficio de nuestros pacientes y de la propia institución.

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A simulation Monte Carlo model was used to assess the economic and financial viability of 130 small-scale dairy farms in central Mexico, through a Representative Small-Scale Dairy Farm. Net yields were calculated for a 9-year planning horizon by means of simulated values for the distribution of input and product prices taking 2010 as base year and considering four scenarios which were compared against the scenario of actual production. The other scenarios were (1) total hiring in of needed labour; (2) external purchase of 100 % of inputs and (3) withdrawal of subsidies to production. A stochastic modelling approach was followed to determine the scenario with the highest economic and financial viability. Results show a viable economic and financial situation for the real production scenario, as well as the scenarios for total hiring of labour and of withdrawal of subsidies, but the scenario when 100 % of feed inputs for the herd are bought-in was not viable.

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Wrack removal has been adopted indiscriminately, with no previous assessment of the ecological implications for sandy beach ecosystem. This study evaluated, through an M-BACI design, the effect of wrack removal on supralittoral arthropods on Atlantic sandy beaches receiving different types of wrack: mangrove propagules (Brazil), seagrasses and macroalgae (Spain). Impacted plots were contrasted with controls in 8 successive periods before and after experimental wrack removal. After the disturbance, drastic decreases in the densities of the amphipod Platorchestia monodi, coleopterans Cleridae, Nitidulidae and Phaleria testacea (Brazilian beaches) and amphipod Talitrus saltator (Spanish beaches) were detected in the impacted plots. The recovery patterns of arthropods might be related to wrack features (amount, composition, and degradation) combined with density and species-specific strategies (e.g. mobility, feeding preferences) in each Atlantic region. The temporary suppression of wrack and its associated fauna can have potential effects on the wrack-derived process and food-web structure on sandy beaches.

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Web-spinning spiders that inhabit stream channels are considered specialists of aquatic ecosystems and are major consumers of emerging aquatic insects, while other spider taxa are more commonly found in riparian forests and as a result may consume more terrestrial insects. To determine if there was a difference in spider taxa abundance between riverine web-spinning spider assemblages within the stream channel and the assemblages 10 m into the riparian forest, we compared abundances for all web-spinning spiders along a headwater stream in El Yunque National Forest in northeast Puerto Rico. By using a nonmetric dimensional scaling (NMDS) abundance analysis we were able to see a clear separation of the two spider assemblages. The second objective of the study was to determine if aquatic insects contributed more to the diet of the spider assemblages closest to the stream channel and therefore stable isotope analyses of δ (15)N and δ (13)C for web-spinning spiders along with their possible prey were utilized. The results of the Bayesian mixing model (SIAR) however showed little difference in the diets of riverine (0 m), riparian (10 m) and upland (25 m) spiders. We found that aquatic insects made up ∼50% of the diet for web-spinning spiders collected at 0 m, 10 m, and 25 m from the stream. This study highlights the importance of aquatic insects as a food source for web-spinning spiders despite the taxonomic differences in assemblages at different distances from the stream.

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The aim of this investigation was to respond the following question: is the consumption of allochthonous resources by Astyanax aff. fasciatus influenced by the longitudinal gradient in streams? To respond this question we sampled fish in the headwater, middle and mouth stretches of four streams (Upper Paraná River basin). Samplings were carried out from July 2007 to June 2008 using electrical fishing. Fish were identified, measured and their stomach contents identified and quantified. Spatial variations (among longitudinal stretches) in the diet were summarized using a principal coordinate analysis (PCoA). Spatial differences in the diet were tested with a multiresponse permutation procedure (MRPP). Allochthonous resources had the highest percentage of the A. aff. fasciatus diet in all stretches; however, the increased importance of autochthonous resources in the fish diet in the stream mouths made these stretches to differ significantly from the middle and headwater ones. The ordination analysis separated the fish diet sampled in the stream mouth from the diet of most fish samples in the headwater and middle stretches. The results highlight the importance of allochthonous resources, mainly insects, in the diet of A. aff. fasciatus. However, the diet was affected by longitudinal gradient and followed the pattern described for these ecosystems, where fish depend basically of allochthonous material in the headwaters and the importance of these resources decrease along the longitudinal gradient.

O objetivo deste estudo foi responder a seguinte pergunta: o consumo de recursos alóctones por Astyanax aff. fasciatus é influenciado pelo gradiente longitudinal dos riachos? Para responder esta questão, foram amostrados peixes na cabeceira, no meio e na foz de quatro riachos (bacia do alto Rio Paraná). As amostragens foram realizadas entre julho/2007 e junho/2008, utilizando-se pesca elétrica. Os peixes foram identificados, medidos e seus conteúdos estomacais identificados e quantificados. Variações espaciais (entre os trechos) na dieta foram sumarizadas através da análise de ordenação de coordenadas principais (PCoA). Diferenças espaciais na dieta foram testadas através do procedimento de permutação de multiresposta (MRPP). Recursos alimentares alóctones compuseram a maior parcela da dieta de A. aff. fasciatus em todos os trechos, porém, na foz dos riachos a dieta diferiu significativamente do meio e da cabeceira, sendo esta diferença causada pelo incremento de recursos autóctones na dieta na foz. A análise de ordenação mostrou a separação da dieta dos peixes amostrados na foz da dieta da maioria dos peixes amostrados na cabeceira e no meio. Estes resultados evidenciam a importância de recursos alóctones, principalmente insetos, na dieta de A. aff. fasciatus. No entanto, a dieta foi influenciada pelo gradiente longitudinal, seguindo o padrão descrito para estes ambientes, onde na cabeceira os peixes dependem primariamente de material alóctone, e ao longo do gradiente ocorre um decréscimo na importância destes recursos.