2,992 research outputs found

    Increasing the reaction kinetics of alkali-activated fly ash binders for stabilisation of a silty sand pavement sub-base

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    The paper addresses several options to improve the reaction kinetics of alkali-activated low-calcium fly ash binders for soil stabilisation in road platforms. For that purpose, an experimental programme was established to assess the strength evolution, with time, of different binders, based on ash, lime, sodium chloride and alkali solutions, applied in the stabilisation of a silty sand. The tests included unconfined compression strength tests, triaxial tests and seismic wave measurements performed at different curing periods. The results were compared with a binder made of Portland cement and a commercial additive specifically designed for soil stabilisation in road applications. The activated ash mixtures with lime were the most performing producing a significant increase in the reactions development and, consequently, in the strength gain rate. The sodium chloride significantly improved the lime and lime-ash mixtures, but provided only a slight improvement in the activated ash mixtures.The authors would like to acknowledge the company CJR Wind – Energy for life, for the funding which enable the presented research; the MCTES/FCT (Portuguese Science and Technology Foundation of Portuguese Ministry of Science and Technology) for their financial support through the SFRH/BPD/85863/2012 scholarship, which is co-funded by the European Social Fund by POCH program; and the Microscopy Unit of the University of Trás- os-Montes e Alto Douro. In addition, a special acknowledgment is also due to PEGOP – Energy Eléctrica, S.A. and LUSICAL – Companhia Lusitana de Cal, S.A. for providing respectively fly ash and lime for this study

    De la mitigación de desastres a la interrupción de trampas de riesgo: la experiencia de aprendizajeacción de clima sin riesgo

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    RESUMEN: En las últimas décadas hemos asistido a una profunda reformulación de cómo entender las condiciones de riesgo en el contexto urbano. Sin embargo, aún enfrentamos significativos desafíos para capturar conceptual, metodológica y empíricamente los círculos viciosos de reproducción de riesgos que configuran ‘trampas de riesgo urbano’ frecuentemente invisibilizadas. Entendemos a las trampas de riesgo como el resultado de la reproducción de riesgos cotidianos y de desastres repetitivos y frecuentes de pequeña escala, que afectan en forma desproporcional a los sectores empobrecidos en forma altamente localizada. A partir de cLIMA sin Riesgo - un proyecto de investigación-acción desarrollado por los autores en el contexto de Lima - este artículo explora las condiciones que producen y reproducen estas trampas, cómo y dónde se materializan, quié- nes son afectados y con qué consecuencias para aquellos que viven en barrios tugurizados y/o asentamientos informales y marginalizados. La discusión examina cómo el conocimiento espacial de la urbanización en riesgo y la evaluación critica de las inversiones y los esfuerzos de mitigación realizados por parte de pobladores y agencias estatales permiten avanzar hacia una apreciación más precisa del impacto de dichas trampas a lo largo del tiempo, así como hacia estrategias de acción para su interrupción. ABSTRACT: The last decades have witnessed a profound change in our understanding of the conditions of risk in urban contexts. However, we still face significant conceptual, methodological and empirical challenges in capturing the vicious cycles of risk accumulation that often render so-called ‘urban risk traps’ invisible. We define risk traps as the result of the reproduction of everyday risks and frequent small-scale disasters, which have highly localized impacts and disproportionately affect impoverished inhabitants. Based on the action-research project cLIMA without Risk (cLIMA sin riesgo), which was conducted by the authors in the context of two marginalized areas in the centre and periphery of Lima, Peru, this article explores the conditions that produce and reproduce these risk traps and it analyses how and where they materialize, who they affect and with what consequences. The discussion examines how spatial knowledge of urbanization at risk together with a critical evaluation of inhabitants’ and state agencies’ investments in mitigation efforts allows us to move towards a more accurate assessment of the impact of these risk traps over time, which is required for developing transformative strategies to disrupt them

    Integrating multicriteria decision analysis and scenario planning : review and extension

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    Scenario planning and multiple criteria decision analysis (MCDA) are two key management science tools used in strategic planning. In this paper, we explore the integration of these two approaches in a coherent manner, recognizing that each adds value to the implementation of the other. Various approaches that have been adopted for such integration are reviewed, with a primary focus on the process of constructing preferences both within and between scenarios. Biases that may be introduced by inappropriate assumptions during such processes are identified, and used to motivate a framework for integrating MCDA and scenario thinking, based on applying MCDA concepts across a range of "metacriteria" (combinations of scenarios and primary criteria). Within this framework, preferences according to each primary criterion can be expressed in the context of different scenarios. The paper concludes with a hypothetical but non-trivial example of agricultural policy planning in a developing country

    Supraclavicular nerve entrapment by the external jugular vein : An unreported finding

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    Publisher Copyright: © 2020 The Author(s)Objective: We aim to describe the supraclavicular nerve's vascular entrapment by the external jugular vein as an unreported anatomical finding. Case description: In a routine cadaveric dissection, the superficial emergence of the first division of the left supraclavicular nerve emerged along a duct formed through the external jugular vein. No other vascular or neural anatomical abnormalities were found in the surrounding structures. Conclusion: This unreported vascular entrapment of the supraclavicular nerve by the external jugular may harbour clinical implications for surgical and endovascular procedures on the external jugular vein and in refractory thoracic and scapular waist pain.Peer reviewe

    Proteasome Dysfunction Associated to Oxidative Stress and Proteotoxicity in Adipocytes Compromises Insulin Sensitivity in Human Obesity

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    AIMS: Obesity is characterized by a low-grade systemic inflammatory state and adipose tissue (AT) dysfunction, which predispose individuals to the development of insulin resistance (IR) and metabolic disease. However, a subset of obese individuals, referred to as metabolically healthy obese (MHO) individuals, are protected from obesity-associated metabolic abnormalities. Here, we aim at identifying molecular factors and pathways in adipocytes that are responsible for the progression from the insulin-sensitive to the insulin-resistant, metabolically unhealthy obese (MUHO) phenotype. RESULTS: Proteomic analysis of paired samples of adipocytes from subcutaneous (SC) and omental (OM) human AT revealed that both types of cells are altered in the MUHO state. Specifically, the glutathione redox cycle and other antioxidant defense systems as well as the protein-folding machinery were dysregulated and endoplasmic reticulum stress was increased in adipocytes from IR subjects. Moreover, proteasome activity was also compromised in adipocytes of MUHO individuals, which was associated with enhanced accumulation of oxidized and ubiquitinated proteins in these cells. Proteasome activity was also impaired in adipocytes of diet-induced obese mice and in 3T3-L1 adipocytes exposed to palmitate. In line with these data, proteasome inhibition significantly impaired insulin signaling in 3T3-L1 adipocytes. INNOVATION: This study provides the first evidence of the occurrence of protein homeostasis deregulation in adipocytes in human obesity, which, together with oxidative damage, interferes with insulin signaling in these cells. CONCLUSION: Our results suggest that proteasomal dysfunction and impaired proteostasis in adipocytes, resulting from protein oxidation and/or misfolding, constitute major pathogenic mechanisms in the development of IR in obesity.IMIBIC/Universidad de Córdoba-SCAI (ProteoRed, PRB2-ISCIII)MINECO/FEDERJunta de Andalucía/FEDERCIBERobn(Instituto de Salud Carlos III

    Socioeconomic inequalities in low birth weight risk before and during the COVID-19 pandemic in Argentina: A cross-sectional study

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    Background: The coronavirus disease 2019 (COVID-19) pandemic may have exacerbated existing socioe- conomic inequalities in health. In Argentina, public hospitals serve the poorest uninsured segment of the population, while private hospitals serve patients with health insurance. This study aimed to assess whether socioeconomic inequalities in low birth weight (LBW) risk changed during the first wave of the COVID-19 pandemic. Methods: This multicenter cross-sectional study included 15929 infants. A difference-in-difference (DID) analysis of socioeconomic inequalities between public and private hospitals in LBW risk in a pandemic cohort (March 20 to July 19, 2020) was compared with a prepandemic cohort (March 20 to July 19, 2019) by using medical records obtained from ten hospitals. Infants were categorized by weight as LBW < 2500 g, very low birth weight (VLBW) < 1500 g and extremely low birth weight (ELBW) < 1000 g. Log binomial regression was performed to estimate risk differences with an interaction term representing the DID estimator. Covariate-adjusted models included potential perinatal confounders. Findings: Of the 8437 infants in the prepandemic cohort, 4887 (57 ? 9%) were born in public hospitals. The pandemic cohort comprised 7492 infants, 4402 (58 ? 7%) of whom were born in public hospitals. The DID estimators indicated no differences between public versus private hospitals for LBW risk ( −1 ? 8% [95% CI −3 ? 6, 0 ? 0]) and for ELBW risk ( −0 ? 1% [95% CI −0 ? 6, 0 ? 3]). Significant differences were found between public versus private hospitals in the DID estimators ( −1 ? 2% [95% CI, −2 ? 1, −0 ? 3]) for VLBW risk. The results were comparable in covariate-adjusted models. Interpretation: In this study, we found evidence of decreased disparities between public and private hos- pitals in VLBW risk. Our findings suggest that measures that prioritize social spending to protect the most vulnerable pregnant women during the pandemic contributed to better birth outcomes. Funding: No funding was secured for this study.Fil: Cuestas, Eduardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Ciencias de la Salud. Universidad Nacional de Córdoba. Instituto de Investigaciones en Ciencias de la Salud; ArgentinaFil: Gómez Flores, Martha E.. Gobierno de la Provincia de Buenos Aires. Hospital Doctor Ramón Carrillo; ArgentinaFil: Charras, María D.. Gobierno de la Provincia de Buenos Aires. Hospital Doctor Ramón Carrillo; ArgentinaFil: Peyrano, Alberto J.. Hospital Materno Provincial Dr. Raúl Felipe Lucini; ArgentinaFil: Montenegro, Clara. Hospital Materno Provincial Dr. Raúl Felipe Lucini; ArgentinaFil: Sosa Boye, Ignacio. No especifíca;Fil: Burgos, Verónica. Universidad Católica de Córdoba. Facultad de Medicina. Clínica Universitaria Reina Fabiola; ArgentinaFil: Giusti, Graciela. Clínica y Maternidad del Sol; ArgentinaFil: Espósito, Mario. Clínica y Maternidad del Sol; ArgentinaFil: Blanco Pool, Silvyana S.. Hospital Misericordia Nuevo Siglo ; Gobierno de la Provincia de Cordoba; ArgentinaFil: Gurevich, Debora P.. Hospital Misericordia Nuevo Siglo ; Gobierno de la Provincia de Cordoba; ArgentinaFil: Ahumada, Luis A.. Hospital Misericordia Nuevo Siglo ; Gobierno de la Provincia de Cordoba; ArgentinaFil: Pontoriero, Ricardo D.. Hospital Misericordia Nuevo Siglo ; Gobierno de la Provincia de Cordoba; ArgentinaFil: Rizzotti, Alina. Hospital Privado Universitario de Córdoba; ArgentinaFil: Bas, José I.. Hospital Privado Universitario de Córdoba; ArgentinaFil: Vaca, María B.. Hospital Universitario de Maternidad y Neonatología; ArgentinaFil: Miranda, María J.. Hospital Universitario de Maternidad y Neonatología; ArgentinaFil: Ferreyra, Mirta E.. Hospital Misericordia Nuevo Siglo ; Gobierno de la Provincia de Cordoba; ArgentinaFil: Moreno, Gabriela C.. Gobierno de la Provincia de Buenos Aires. Hospital Doctor Ramón Carrillo; ArgentinaFil: Pedicino, Héctor. Hospital Italiano; ArgentinaFil: Rojas Rios, Melvy. Hospital Italiano; Argentin

    Estimating mortality and disability in Peru before the COVID-19 pandemic: a systematic analysis from the Global Burden of the Disease Study 2019

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    "Background: Estimating and analyzing trends and patterns of health loss are essential to promote efficient resource allocation and improve Peru’s healthcare system performance. Methods: Using estimates from the Global Burden of Disease (GBD), Injuries, and Risk Factors Study (2019), we assessed mortality and disability in Peru from 1990 to 2019. We report demographic and epidemiologic trends in terms of population, life expectancy at birth (LE), mortality, incidence, prevalence, years of life lost (YLLs), years lived with disability (YLDs), and disability-adjusted life-years (DALYs) caused by the major diseases and risk factors in Peru. Finally, we compared Peru with 16 countries in the Latin American (LA) region. Results: The Peruvian population reached 33.9 million inhabitants (49.9% women) in 2019. From 1990 to 2019, LE at birth increased from 69.2 (95% uncertainty interval 67.8–70.3) to 80.3 (77.2–83.2) years. This increase was driven by the decline in under-5 mortality (−80.7%) and mortality from infectious diseases in older age groups (+60 years old). The number of DALYs in 1990 was 9.2 million (8.5–10.1) and reached 7.5 million (6.1–9.0) in 2019. The proportion of DALYs due to non-communicable diseases (NCDs) increased from 38.2% in 1990 to 67.9% in 2019. The all-ages and age-standardized DALYs rates and YLLs rates decreased, but YLDs rates remained constant. In 2019, the leading causes of DALYs were neonatal disorders, lower respiratory infections (LRIs), ischemic heart disease, road injuries, and low back pain. The leading risk factors associated with DALYs in 2019 were undernutrition, high body mass index, high fasting plasma glucose, and air pollution. Before the COVID-19 pandemic, Peru experienced one of the highest LRIs-DALYs rates in the LA region. Conclusion: In the last three decades, Peru experienced significant improvements in LE and child survival and an increase in the burden of NCDs and associated disability. The Peruvian healthcare system must be redesigned to respond to this epidemiological transition. The new design should aim to reduce premature deaths and maintain healthy longevity, focusing on effective coverage and treatment of NCDs and reducing and managing the related disability.

    Association between COVID-19 mandatory lockdown and decreased incidence of preterm births and neonatal mortality

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    Previous studies suggest a decrease in preterm births (PTB) during de coronavirus disease 2019 (COVID-19), possibly due to the effect of the mandatory lockdown. Nevertheless, other reports have been unable to confirm this finding. Most of these studies originated in high-income countries and evaluated a limited number of potential confounders, and all of them assessed a short lockdown period. In addition, an important question remains unanswered: How can we be sure that the observed changes are due to lockdown, when most of the pregnancies delivered in the lockdown period were conceived prior to it?To date there is insufficient evidence to support the notion that public health interventions during the lockdown prevent PTB . The aim of this study was to compare the incidence of PTB, neonatal mortality (NM) and stillbirths adjusted by potential confounders during the lockdown period assessing a time window of nine and a half months during which all the pregnancies analyzed in the exposed group were conceived after the lockdown, with the corresponding incidence in the previous year where all the unexposed pregnancies analyzed were conceived before the lockdown.publishedVersionFil: Cuestas, Eduardo. Universidad Nacional de Córdoba. Facultad de Ciencias Médicas; Argentina.Fil: Cuestas, Eduardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Ciencias de la Salud; Argentina.Fil: Gómez Flores, Martha E. Gobierno de la Provincia de Buenos Aires. Hospital Doctor Ramon Carrillo; Argentina.Fil: Charras, María D. Gobierno de la Provincia de Buenos Aires. Hospital Doctor Ramon Carrillo; Argentina.Fil: Peyrano, Alberto J. Hospital Materno Provincial Dr. Raúl Felipe Lucini; Argentina.Fil: Montenegro, Clara. Hospital Materno Provincial Dr. Raúl Felipe Lucini; Argentina.Fil: Sosa-Boye, Ignacio. Clínica Universitaria Reina Fabiola; Argentina.Fil: Burgos, Verónica. Clínica Universitaria Reina Fabiola; Argentina.Fil: Giusti, Graciela. Clínica y Maternidad del Sol; Argentina.Fil: Espósito, Mario. Clínica y Maternidad del Sol; Argentina.Fil: Blanco Pool, Silvyana S. Hospital Misericordia Nuevo Siglo; Argentina.Fil: Blanco Pool, Silvyana S. Sanatorio Allende; Argentina.Fil: Gurevich, Debora P. Sanatorio Allende; Argentina.Fil: Gurevich, Debora P. Hospital Misericordia Nuevo Siglo; Argentina.Fil: Ahumada, Luis A. Sanatorio Allende; Argentina.Fil: Ahumada, Luis A. Hospital Misericordia Nuevo Siglo; Argentina.Fil: Pontoriero, Ricardo D. Hospital Misericordia Nuevo Siglo; Argentina.Fil: Rizzotti, Alina. Hospital Privado Universitario de Córdoba; Argentina.Fil: Bas, José I. Hospital Privado Universitario de Córdoba; Argentina.Fil: Vaca, María B. Hospital Universitario de Maternidad y Neonatología; Argentina.Fil: Miranda, María J. Hospital Universitario de Maternidad y Neonatología; Argentina.Fil: Ferreyra, Mirta E. Sanatorio del Salvador; Argentina.Fil: Ferreyra, Mirta E. Hospital Misericordia Nuevo Siglo; Argentina.Fil: Moreno, Gabriela C. Sanatorio del Salvador; Argentina.Fil: Pedicino, Héctor. Instituto Universidad Escuela de Medicina del Hospital Italiano; Argentina.Fil: Rojas-Rios, Melvy. Instituto Universidad Escuela de Medicina del Hospital Italiano; Argentina

    Evaluating the influence of environmental variables on fish assemblages along Tropical Andes: considerations from ecology to conservation

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    The lack of knowledge about freshwater biodiversity in remote areas like montane Andean rivers is noticeable and hinder the development of efficient conservation plans for aquatic ecosystems. Habitat requirements of tropical Andean fishes have been poorly analysed, despite the relevance of these ecological features on the fish conservation strategies. The present study aimed to examine fish assemblages along the altitudinal gradient in tropical Andean rivers and their relationship to habitat features to detect the most relevant abiotic factors and their implication on conservation. This study was conducted on a regional scale, along six basins located in tropical Andes (500 to 2,692 m a.s.l.). We studied fish diversity and distribution and their habitats along these elevation gradients. We found 6,320 specimens from 53 genera. Our analysis for the six most common and widely distributed genera (Astroblepus, Brycon, Bryconamericus, Chaetostoma, Pimelodella and Trichomycterus) underlines the relevance of hydromorphological variables on fish community structure in the Andean montane rivers, whereas human alterations seem to be less significant. These findings could be useful for current management and conservation strategies considering present threats over tropical montane rivers
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