1,003 research outputs found

    Mapeo de Actores y Necesidades de Información Agroclimática en los Cultivos de Maíz y Frijol en sitios piloto - Colombia

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    Este trabajo presenta los resultados del mapeo de actores y necesidades de información agroclimática en los cultivos transitorios de seguridad alimentaria: maíz y frijol arbustivo en sitios piloto en Colombia. A través del mapeo de los actores que transmiten información a los agricultores, la confianza en la información proporcionada, y las necesidades de información para la toma de decisiones, logramos entender el ancho espectro de problemas y prioridades a tomar en cuenta en la producción de estos cultivos, y proponer soluciones útiles, relevantes, confiables, sostenibles y aplicables. Con este enfoque, se llevaron a cabo 27 entrevistas semi-estructuradas con informantes clave y 12 grupos focales con un total de 151 agricultores en los departamentos de Córdoba y Santander. Los resultados evidencian que una de las prioridades de los agricultores es recibir información agroclimática confiable a escala local, que permita tomar mejores decisiones de siembra, variedades, insumos y manejo de suelos y cultivos ante eventos de variabilidad climática. Se evidencia una desconfianza en las instituciones oficiales que transmiten información climática y un sentimiento difuso de falta de interés de las instituciones hacia los pequeños agricultores. Los agricultores se endeudan para lograr producir fríjol arbustivo y maíz o subsidian la producción por otros cultivos, mientras el acceso a un seguro agrícola es limitado. El formato preferido para recibir información climática es a través de mensajes de texto (celular) y mensajes en la radio local. Grupos de interacción presencial o virtual entre agricultores y expertos parecen una alternativa útil y confiable para recibir y compartir información en tiempo real. Sin embargo, los agricultores están interesados en adoptar el manejo agrícola tras un pronóstico si: a) la información es local, b) proviene de una fuente considerada confiable como expertos u otros agricultores, c) se transmite en el momento adecuado para la toma de decisiones y d) si sus efectos son medibles, verificables y validados, por ejemplo, a través de resultados de pilotos o parcelas experimentales en dos años consecutivos. ENGLISH This working paper presents the results of the mapping of actors and of agroclimatic information needs in pilot sites in Colombia for two annual crops, fundamental for food security: maize and bush beans. The mapping of the actors that transmit information to farmers, the confidence the latter have in the information provided, and their information needs for decision-making, allows us to understand the broad spectrum of issues and priorities to be taken into account in the production of these crops, and suggest solutions that are useful, relevant, reliable, sustainable and applicable. Under this assumption, we conducted 27 semi-structured interviews with key informants and 12 focus groups with a total of 151 farmers in the departments of Córdoba and Santander. Results show that one of the priorities of farmers is to receive reliable local agroclimatic information that enables them to take decisions on planting, varieties, inputs, soil and crop management, that address climate variability. We find a generalized distrust of official institutions that transmit weather information, and a feeling that institutions are not interested in smallholders. Farmers resort to indebtedness to produce beans and maize, or subsidize production with cash crops, while access to agricultural insurance is limited. The format preferred to receive weather information is text messages (phone) and information through the local radio. The creation of groups of farmers and experts who interact in person or virtually seem a useful and reliable alternative to receive and share information in real time. However, farmers are only interested in adopting farm management changes after a forecast if: a) the information is local, b) the information is given by a trusted source such as experts or other farmers, c) the information is transmitted at the right time for decision-making d) the effects of taking these decisions are measurable, verifiable and validated, for example, through pilots or results from experimental plots in two consecutive years

    Conscious mobility for urban spaces: case studies review and indicator framework design

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    A lack of data collection on conscious mobility behaviors has been identified in current sustainable and smart mobility planning, development and implementation strategies. This leads to technocentric solutions that do not place people and their behavior at the center of new mobility solutions in urban centers around the globe. This paper introduces the concept of conscious mobility to link techno-economic analyses with user awareness on the impact of their travel decisions on other people, local urban infrastructure and the environment through systematic big data collection. A preliminary conscious mobility indicator framework is presented to leverage behavioral considerations to enhance urban-community mobility systems. Key factors for conscious mobility analysis have been derived from five case studies. The sample offers regional diversity (i.e., local, regional and the global urban contexts), as well as different goals in the transformation of conventional urban transport systems, from improving public transport efficiency and equipment electrification to mitigate pollution and climate risks, to focusing on equity, access and people safety. The case studies selected provide useful metrics on the adoption of cleaner, smarter, safer and more autonomous mobility technologies, along with novel people-centric program designs to build an initial set of conscious mobility indicators frameworks. The parameters were applied to the city of Monterrey, Nuevo Leon in Mexico focusing on the needs of the communities that work, study and live around the local urban campus of the Tecnologico de Monterrey’s Distrito Tec. This case study, served as an example of how conscious mobility indicators could be applied and customized to a community and region of interest. This paper introduces the first application of the conscious mobility framework for urban communities’ mobility system analysis. This more holistic assessment approach includes dimensions such as society and culture, infrastructure and urban spaces, technology, government, normativity, economy and politics, and the environment. The expectation is that the conscious mobility framework of analysis will become a useful tool for smarter and sustainable urban and mobility problem solving and decision making to enhance the quality of life all living in urban communities

    The O3N2 and N2 abundance indicators revisited: improved calibrations based on CALIFA and Te-based literature data

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    The use of IFS is since recently allowing to measure the emission line fluxes of an increasingly large number of star-forming galaxies both locally and at high redshift. The main goal of this study is to review the most widely used empirical oxygen calibrations, O3N2 and N2, by using new direct abundance measurements. We pay special attention to the expected uncertainty of these calibrations as a function of the index value or abundance derived and the presence of possible systematic offsets. This is possible thanks to the analysis of the most ambitious compilation of Te-based HII regions to date. This new dataset compiles the Te-based abundances of 603 HII regions extracted from the literature but also includes new measurements from the CALIFA survey. Besides providing new and improved empirical calibrations for the gas abundance, we also present here a comparison between our revisited calibrations with a total of 3423 additional CALIFA HII complexes with abundances derived using the ONS calibration by Pilyugin et al. (2010). The combined analysis of Te-based and ONS abundances allows us to derive their most accurate calibration to date for both the O3N2 and N2 single-ratio indicators, in terms of all statistical significance, quality and coverage of the space of parameters. In particular, we infer that these indicators show shallower abundance dependencies and statistically-significant offsets compared to those of Pettini and Pagel (2004), Nagao et al. (2006) and P\'erez-Montero and Contini (2009). The O3N2 and N2 indicators can be empirically applied to derive oxygen abundances calibrations from either direct abundance determinations with random errors of 0.18 and 0.16, respectively, or from indirect ones (but based on a large amount of data) reaching an average precision of 0.08 and 0.09 dex (random) and 0.02 and 0.08 dex (systematic; compared to the direct estimations),respectively.Comment: 12 pages, 5 figures, accepted for publication in A&

    The Mass-Metallicity relation explored with CALIFA: I. Is there a dependence on the star formation rate?

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    We present the results on the study of the global and local M-Z relation based on the first data available from the CALIFA survey (150 galaxies). This survey provides integral field spectroscopy of the complete optical extent of each galaxy (up to 2-3 effective radii), with enough resolution to separate individual HII regions and/or aggregations. Nearly \sim3000 individual HII regions have been detected. The spectra cover the wavelength range between [OII]3727 and [SII]6731, with a sufficient signal-to-noise to derive the oxygen abundance and star-formation rate associated with each region. In addition, we have computed the integrated and spatially resolved stellar masses (and surface densities), based on SDSS photometric data. We explore the relations between the stellar mass, oxygen abundance and star-formation rate using this dataset. We derive a tight relation between the integrated stellar mass and the gas-phase abundance, with a dispersion smaller than the one already reported in the literature (σΔlog(O/H)=\sigma_{\Delta{\rm log(O/H)}}=0.07 dex). Indeed, this dispersion is only slightly larger than the typical error derived for our oxygen abundances. However, we do not find any secondary relation with the star-formation rate, other than the one induced due to the primary relation of this quantity with the stellar mass. We confirm the result using the \sim3000 individual HII regions, for the corresponding local relations. Our results agree with the scenario in which gas recycling in galaxies, both locally and globally, is much faster than other typical timescales, like that of gas accretion by inflow and/or metal loss due to outflows. In essence, late-type/disk dominated galaxies seem to be in a quasi-steady situation, with a behavior similar to the one expected from an instantaneous recycling/closed-box model.Comment: 19 Pages, 8 figures, Accepted for Publishing in Astronomy and Astrophysics (A&A

    The Association of Arsenic Exposure and Metabolism With Type 1 and Type 2 Diabetes in Youth: The SEARCH Case-Control Study

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    Little is known about arsenic and diabetes in youth. We examined the association of arsenic with type 1 and type 2 diabetes in the SEARCH for Diabetes in Youth Case-Control (SEARCH-CC) study. Because one-carbon metabolism can influence arsenic metabolism, we also evaluated the potential interaction of folate and vitamin B12 with arsenic metabolism on the odds of diabetes

    CANDELS: The progenitors of compact quiescent galaxies at z~2

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    We combine high-resolution HST/WFC3 images with multi-wavelength photometry to track the evolution of structure and activity of massive (log(M*) > 10) galaxies at redshifts z = 1.4 - 3 in two fields of the Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey (CANDELS). We detect compact, star-forming galaxies (cSFGs) whose number densities, masses, sizes, and star formation rates qualify them as likely progenitors of compact, quiescent, massive galaxies (cQGs) at z = 1.5 - 3. At z > 2 most cSFGs have specific star-formation rates (sSFR = 10^-9 yr^-1) half that of typical, massive SFGs at the same epoch, and host X-ray luminous AGN 30 times (~30%) more frequently. These properties suggest that cSFGs are formed by gas-rich processes (mergers or disk-instabilities) that induce a compact starburst and feed an AGN, which, in turn, quench the star formation on dynamical timescales (few 10^8 yr). The cSFGs are continuously being formed at z = 2 - 3 and fade to cQGs by z = 1.5. After this epoch, cSFGs are rare, thereby truncating the formation of new cQGs. Meanwhile, down to z = 1, existing cQGs continue to enlarge to match local QGs in size, while less-gas-rich mergers and other secular mechanisms shepherd (larger) SFGs as later arrivals to the red sequence. In summary, we propose two evolutionary scenarios of QG formation: an early (z > 2), fast-formation path of rapidly-quenched cSFGs that evolve into cQGs that later enlarge within the quiescent phase, and a slow, late-arrival (z < 2) path for SFGs to form QGs without passing through a compact state.Comment: Submitted to the Astrophysical Journal Letters, 6 pages, 4 figure

    Galectin-1 prevents pathological vascular remodeling in atherosclerosis and abdominal aortic aneurysm

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    Pathological vascular remodeling is the underlying cause of atherosclerosis and abdominal aortic aneurysm (AAA). Here, we analyzed the role of galectin-1 (Gal-1), a β-galactoside-binding protein, as a therapeutic target for atherosclerosis and AAA. Mice lacking Gal-1 (Lgals1 −/− ) developed severe atherosclerosis induced by pAAV/D377Y-mPCSK9 adenovirus and displayed higher lipid levels and lower expression of contractile markers of vascular smooth muscle cells (VSMCs) in plaques than wild-type mice. Proteomic analysis of Lgals1 −/− aortas showed changes in markers of VSMC phenotypic switch and altered composition of mitochondrial proteins. Mechanistically, Gal-1 silencing resulted in increased foam cell formation and mitochondrial dysfunction in VSMCs, while treatment with recombinant Gal-1 (rGal-1) prevented these effects. Furthermore, rGal-1 treatment attenuated atherosclerosis and elastase-induced AAA, leading to higher contractile VSMCs in aortic tissues. Gal-1 expression decreased in human atheroma and AAA compared to control tissue. Thus, Gal-1-driven circuits emerge as potential therapeutic strategies in atherosclerosis and AAA. Galectin-1 plays an essential role in prevention of atherosclerosis and abdominal aortic aneurysm

    Social sciences research in neglected tropical diseases 2: A bibliographic analysis

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    The official published version of the article can be found at the link below.Background There are strong arguments for social science and interdisciplinary research in the neglected tropical diseases. These diseases represent a rich and dynamic interplay between vector, host, and pathogen which occurs within social, physical and biological contexts. The overwhelming sense, however, is that neglected tropical diseases research is a biomedical endeavour largely excluding the social sciences. The purpose of this review is to provide a baseline for discussing the quantum and nature of the science that is being conducted, and the extent to which the social sciences are a part of that. Methods A bibliographic analysis was conducted of neglected tropical diseases related research papers published over the past 10 years in biomedical and social sciences. The analysis had textual and bibliometric facets, and focussed on chikungunya, dengue, visceral leishmaniasis, and onchocerciasis. Results There is substantial variation in the number of publications associated with each disease. The proportion of the research that is social science based appears remarkably consistent (<4%). A textual analysis, however, reveals a degree of misclassification by the abstracting service where a surprising proportion of the "social sciences" research was pure clinical research. Much of the social sciences research also tends to be "hand maiden" research focused on the implementation of biomedical solutions. Conclusion There is little evidence that scientists pay any attention to the complex social, cultural, biological, and environmental dynamic involved in human pathogenesis. There is little investigator driven social science and a poor presence of interdisciplinary science. The research needs more sophisticated funders and priority setters who are not beguiled by uncritical biomedical promises
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