53 research outputs found

    Modelamiento estocástico de variabilidad hidrológica a escalas de alta resolución temporal

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    El estudio de sistemas complejos puede ser abordados desde distintos enfoques. En hidrología, el uso de enfoques estocásticos ha sido aplicado desde principios de siglo pasado, sin embargo, en la mayoría de los casos se asume independencias en las variables que describe el sistema hidrológico. En este trabajo se aproxima la ecuación de Folkker-Planck- Kolmogorov (FPK) bidimensionales como supraoperador matemático mediante un esquema numérico en diferencias finitas explicitas para describir la variabilidad hidrológica a escalas temporales fijas bajo condiciones no estacionarias, representado lo anterior, como la evaluación temporal de la curva de densidad de probabilidad condicionada (CDPC) de sistemas hidrológicos instrumentadas en el territorio colombiano.Magíster en HidrosistemasMaestrí

    Do synthesis centers synthesize? A semantic analysis of topical diversity in research

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    Synthesis centers are a form of scientific organization that catalyzes and supports research that integrates diverse theories, methods and data across spatial or temporal scales to increase the generality, parsimony, applicability, or empirical soundness of scientific explanations. Synthesis working groups are a distinctive form of scientific collaboration that produce consequential, high-impact publications. But no one has asked if synthesis working groups synthesize: are their publications substantially more diverse than others, and if so, in what ways and with what effect? We investigate these questions by using Latent Dirichlet Analysis to compare the topical diversity of papers published by synthesis center collaborations with that of papers in a reference corpus. Topical diversity was operationalized and measured in several ways, both to reflect aggregate diversity and to emphasize particular aspects of diversity (such as variety, evenness, and balance). Synthesis center publications have greater topical variety and evenness, but less disparity, than do papers in the reference corpus. The influence of synthesis center origins on aspects of diversity is only partly mediated by the size and heterogeneity of collaborations: when taking into account the numbers of authors, distinct institutions, and references, synthesis center origins retain a significant direct effect on diversity measures. Controlling for the size and heterogeneity of collaborative groups, synthesis center origins and diversity measures significantly influence the visibility of publications, as indicated by citation measures. We conclude by suggesting social processes within collaborations that might account for the observed effects, by inviting further exploration of what this novel textual analysis approach might reveal about interdisciplinary research, and by offering some practical implications of our results.publishedVersio

    SMS-Builder: An adaptive software tool for building systematic mapping studies

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    A Systematic Mapping Study is an instrument frequently used to carry out a search process, identification, and classification of studies in different fields. Researchers in front of this type of process have a challenge while managing the data about these studies. This paper presents a software tool that has been created to help those who need to build a systematic mapping study. In addition, this work follows the evidence-based software engineering approach and extends it through a software tool by including different ways of adapting this process

    Programa de promoción y prevención “Mamitas sanas, familias felices” para disminuir la mortalidad materna en el Putumayo

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    El presente trabajo es una propuesta de un programa de promoción de la salud y prevención de enfermedades para mitigar y reducir el numero de muertes maternas, los cuales son eventos lamentables que son repudiados en muchos países y son indicadores de pobreza. Este programa esta enfocado a mujeres en edades de entre 15 a 44 años, las cuales son mas susceptibles a embarazos, en especial de alto riesgo en los extremos de este rango de edades que pueden convertirse en muertes maternas.The present work is a proposal for a health promotion and disease prevention program to mitigate and reduce the number of maternal deaths, which are regrettable events that are repudiated in many countries and are indicators of poverty. This program is focused on women between the ages of 15 and 44, who are more susceptible to pregnancies, especially high-risk ones at the extremes of this age range that can lead to maternal deaths

    A decentralized approach to model national and global food and land use systems

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    The achievement of several sustainable development goals and the Paris Climate Agreement depends on rapid progress towards sustainable food and land systems in all countries. We have built a flexible, collaborative modeling framework to foster the development of national pathways by local research teams and their integration up to global scale. Local researchers independently customize national models to explore mid-century pathways of the food and land use system transformation in collaboration with stakeholders. An online platform connects the national models, iteratively balances global exports and imports, and aggregates results to the global level. Our results show that actions toward greater sustainability in countries could sum up to 1 Mha net forest gain per year, 950 Mha net gain in the land where natural processes predominate, and an increased CO2 sink of 3.7 GtCO2e yr−1 over the period 2020-2050 compared to current trends, while average food consumption per capita remains above the adequate food requirements in all countries. We show examples of how the global linkage impacts national results and how different assumptions in national pathways impact global results. This modeling setup acknowledges the broad heterogeneity of socio-ecological contexts and the fact that people who live in these different contexts should be empowered to design the future they want. But it also demonstrates to local decision-makers the interconnectedness of our food and land use system and the urgent need for more collaboration to converge local and global priorities.Fil: Mosnier, Aline. Sustainable Development Solutions Network; FranciaFil: Javalera Rincon, Valeria. International Institute For Applied Systems Analysis, Laxenburg; AustriaFil: Jones, Sarah K. Alliance of Bioversity International; FranciaFil: Andrew, Robbie. Center for International Climate Research; NoruegaFil: Bai, Zhaohai. Chinese Academy of Sciences; República de ChinaFil: Baker, Justin. North Carolina State University; Estados UnidosFil: Basnet, Shyam. Stockholm Resilience Centre; SueciaFil: Boer, Rizaldi. Bogor Agricultural University; IndonesiaFil: Chavarro, John. Geo-agro-environmental Sciences And Resources Research Center; ColombiaFil: Costa, Wanderson. Centro de Previsao de Tempo e Estudos Climáticos. Instituto Nacional de Pesquisas Espaciais; BrasilFil: Daloz, Anne Sophie. Center for International Climate Research; NoruegaFil: DeClerck, Fabrice A.. Alliance of Bioversity International; Francia. Stockholm Resilience Centre; SueciaFil: Diaz, Maria. Sustainable Development Solutions Network; FranciaFil: Douzal, Clara. Sustainable Development Solutions Network; FranciaFil: Howe Fan, Andrew Chiah. Sunway University; MalasiaFil: Fetzer, Ingo. Stockholm Resilience Centre; SueciaFil: Frank, Federico. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires; ArgentinaFil: Gonzalez Abraham, Charlotte E.. University of California at San Diego; Estados UnidosFil: Habiburrachman, A. H. F.. Universitas Indonesia; IndonesiaFil: Immanuel, Gito. Stockholm Resilience Centre; SueciaFil: Harrison, Paula A.. Centre for Ecology & Hydrology; Reino UnidoFil: Imanirareba, Dative. Uganda Martyrs University; UgandaFil: Jha, Chandan. Indian Institute Of Management Ahmedabad; IndiaFil: Monjeau, Jorge Adrian. Fundación Bariloche; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Vittis, Yiorgos. International Institute For Applied Systems Analysis; AustriaFil: Wade, Chris. North Carolina State University; Estados UnidosFil: Winarni, Nurul L.. Universitas Indonesia; IndonesiaFil: Woldeyes, Firew Bekele. Ethiopian Development Research Institute; EtiopíaFil: Wu, Grace C.. University of California; Estados UnidosFil: Zerriffi, Hisham. University of British Columbia; Canad

    Liderazgo, emprendimiento y autogestión: Aportes desde el saber pedagógico para la educación del siglo XXI

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    110 páginas. Libro ElectrónicoEl ejercicio que se plantea en el marco de la línea Liderazgo, emprendimiento y autogestión, se diseñó con el fin de pensar y repensar diversas prácticas pedagógicas que interpelan la escuela. De manera específica, diez propuestas de maestras y maestros inspiradores que, con tiempos, experiencias y objetivos distintos, se han venido pensando lugares del liderazgo y la gestión en la escuela.Primera edició

    The effect of cigarette smoking, alcohol consumption and fruit and vegetable consumption on IVF outcomes: A review and presentation of original data

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    Background - Lifestyle factors including cigarette smoking, alcohol consumption and nutritional habits impact on health, wellness, and the risk of chronic diseases. In the areas of in-vitro fertilization (IVF) and pregnancy, lifestyle factors influence oocyte production, fertilization rates, pregnancy and pregnancy loss, while chronic, low-grade oxidative stress may underlie poor outcomes for some IVF cases. Methods - Here, we review the current literature and present some original, previously unpublished data, obtained from couples attending the PIVET Medical Centre in Western Australia. Results - During the study, 80 % of females and 70 % of male partners completed a 1-week diary documenting their smoking, alcohol and fruit and vegetable intake. The subsequent clinical outcomes of their IVF treatment such as quantity of oocytes collected, fertilization rates, pregnancy and pregnancy loss were submitted to multiple regression analysis, in order to investigate the relationship between patients, treatment and the recorded lifestyle factors. Of significance, it was found that male smoking caused an increased risk of pregnancy loss (p = 0.029), while female smoking caused an adverse effect on ovarian reserve. Both alcohol consumption (β = 0.074, p < 0.001) and fruit and vegetable consumption (β = 0.034, p < 0.001) had positive effects on fertilization. Conclusion - Based on our results and the current literature, there is an important impact of lifestyle factors on IVF clinical outcomes. Currently, there are conflicting results regarding other lifestyle factors such as nutritional habits and alcohol consumption, but it is apparent that chronic oxidative stress induced by lifestyle factors and poor nutritional habits associate with a lower rate of IVF success

    Genome-wide analysis identifies genetic effects on reproductive success and ongoing natural selection at the FADS locus

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    : Identifying genetic determinants of reproductive success may highlight mechanisms underlying fertility and identify alleles under present-day selection. Using data in 785,604 individuals of European ancestry, we identified 43 genomic loci associated with either number of children ever born (NEB) or childlessness. These loci span diverse aspects of reproductive biology, including puberty timing, age at first birth, sex hormone regulation, endometriosis and age at menopause. Missense variants in ARHGAP27 were associated with higher NEB but shorter reproductive lifespan, suggesting a trade-off at this locus between reproductive ageing and intensity. Other genes implicated by coding variants include PIK3IP1, ZFP82 and LRP4, and our results suggest a new role for the melanocortin 1 receptor (MC1R) in reproductive biology. As NEB is one component of evolutionary fitness, our identified associations indicate loci under present-day natural selection. Integration with data from historical selection scans highlighted an allele in the FADS1/2 gene locus that has been under selection for thousands of years and remains so today. Collectively, our findings demonstrate that a broad range of biological mechanisms contribute to reproductive success

    Genome-wide analysis identifies 12 loci influencing human reproductive behavior.

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    The genetic architecture of human reproductive behavior-age at first birth (AFB) and number of children ever born (NEB)-has a strong relationship with fitness, human development, infertility and risk of neuropsychiatric disorders. However, very few genetic loci have been identified, and the underlying mechanisms of AFB and NEB are poorly understood. We report a large genome-wide association study of both sexes including 251,151 individuals for AFB and 343,072 individuals for NEB. We identified 12 independent loci that are significantly associated with AFB and/or NEB in a SNP-based genome-wide association study and 4 additional loci associated in a gene-based effort. These loci harbor genes that are likely to have a role, either directly or by affecting non-local gene expression, in human reproduction and infertility, thereby increasing understanding of these complex traits

    Comparing trends in hydrometeorological average and extreme data sets around the world at different time scales

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    Study region: The Present work shows trend analysis results for temperature and precipitation around the world and for river discharges in the Americas, Australia and some European countries for a common time period with free access hydrometeorological information. Study focus: Hydrometeorological data sets for discharge, precipitation and temperature around the world were analysed for statistically significant trends both in average and extreme value data sets between 1970 and 2010. The data was analysed with the Mann–Kenndall trend test at annual, monthly and daily resolutions, to compare the results on a global scale and between the different time resolutions. New hydrological insights for the region: Results indicate that trends can be found for all variables and on all latitudes, with an increase of global temperature in the analysed time period. Fewer trends were observed in extreme value data. Trends in discharge data were predominantly negative, and precipitation trends were not very common. In some cases, an opposing pattern was observed in the northern and southern hemisphere. The highest number of trends was found at the annual and least on the daily resolution, nevertheless, trend patterns for discharges remained similar at different time scales. Some of the factors that might influence these results are discussed. Keywords: Trend analysis, Hydrometeorological data sets, Extreme event, Mann–Kendall trend test, Time resolution, Global analysi
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