561 research outputs found

    Industrialización de la riqueza vegetal: oportunidades sociales y económicas

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    Las empresas enfrentan un importante desafío es esta economía globalizada, porque para sobrevivir tienen que ofrecer nuevos productos con valor agregado en los mercados internacionales. Para ello se requieren profesionales entrenados en las metodologías para el desarrollo de nuevos productos (DNP), y los egresados universitarios tienen que tener estas habilidades para que puedan contribuir a enfrentar esta situación. J unto con esto se requieren también productos innovadores de la mano con la conservación del medio ambiente y aprovechando al máximo los recursos disponibles, bien sea de la tierra o de transformación tecnológica. Con este proyecto se pretende abrir una ventana de oportunidad para que los alumnos del programa de Ingeniería de Procesos puedan adquirir el entrenamiento necesario para desempeñarse con éxito en el DNP. A demás, los empresarios del campo puedan obtener un valor agregado para sus productos como alternativa en tiempos de precios desfavorables.Companies face a major challenge is this globalized economy, because to survive they have to offer new products with added value in the international market. This requires professionals trained in the methodologies for the development of new products (DNP) and university graduates must have these skills so that they can contribute to deal with this situation. A long with this they also require innovations running by the side of conservation of the environment and the taking of full advantage of available resources, either from land or technological transformation. This project is to open a window of opportunity so that the Process Engineering students can acquire the knowledge needed to perform successfully in the DNP training. A lso field employers can get valueadded products as an alternative in times of unfavourable prices

    Efecto de Cuatro Métodos de Separación Seminal sobre la Calidad y la Capacidad Fertilizante in vitro de Espermatozoides Equinos Criopreservados

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    The aim of this study was to evaluate the effect of four separation methods on seminal quality and in vitro fertilizing capacity of equine cryopreserved spermatozoa. Straws of equine cryopreserved semen were used for sperm separation through the Androcoll, CushionFluid, EquiPure and Percoll methods. A Sperm Class Analyzer (SCA®) system was used to determine total motility, progressive motility, curvilinear velocity, linear velocity and average speed. Also, intact acrosome and sperm vitality were evaluated by fluorescence microscopy. In vitro fertilizing capacity was assessed by in vitro fertilization of bovine oocytes with spermatozoa obtained by each separation method.Cleavage rates were determined after three days of in vitro culture. The results were analyzed using generalized linear models (GLM) and means of the four methods were compared using the Tukey test. The CushionFluid was superior for most parameters of sperm motility as well as for intact acrosome (p<0.05). Higher means of sperm vitality were obtained with EquiPure and Percoll (p<0.05), but no difference were found on cleavage rates between treatments. It was concluded that cryopreserved stallion semen selected by the CushionFluid method had better sperm quality compared to the other three methods; however no difference was evident between them for in vitro fertilizing capacity of spermatozoa.El objetivo del presente estudio fue evaluar el efecto de cuatro métodos de separación seminal sobre la calidad y la capacidad fertilizante in vitro de espermatozoides equinos criopreservados. Se utilizaron pajillas de semen equino criopreservado para la separación espermática a través de los métodos Androcoll, CushionFluid, EquiPure y Percoll. Mediante un sistema analizador de clase (SCA®) se evaluó la motilidad total, motilidad progresiva, velocidad curvilínea, velocidad lineal y velocidad media, y por microscopía de fluorescencia se determinaron los acrosomas intactos y la vitalidad espermática. La evaluación de la capacidad fertilizante in vitro se realizó mediante la fertilización in vitro de oocitos bovinos con espermatozoides obtenidos en cada método de separación. El clivaje se determinó después de tres días de cultivo in vitro. Los resultados se analizaron mediante modelos lineales generalizados (GLM) y las medias para los diferentes métodos se compararon usando la prueba de Tukey. El CushionFluid fue superior para la mayoría de parámetros de movilidad espermática, así como para acrosomas intactos (p<0.05). Se encontraron medias superiores de vitalidad espermática para EquiPure y Percoll (p<0.05), pero no se encontró diferencia entre las medias de clivaje entre tratamientos. Se concluye que el semen equino criopreservado y seleccionado por el método CushionFluid presenta mejores parámetros de calidad espermática respecto a los otros tres métodos; sin embargo, no se evidencia diferencia entre ellos para la capacidad fertilizante in vitro de los espermatozoides

    Fragmentation of Andes-to-Amazon connectivity by hydropower dams

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    Andes-to-Amazon river connectivity controls numerous natural and human systems in the greater Amazon. However, it is being rapidly altered by a wave of new hydropower development, the impacts of which have been previously underestimated. We document 142 dams existing or under construction and 160 proposed dams for rivers draining the Andean headwaters of the Amazon. Existing dams have fragmented the tributary networks of six of eight major Andean Amazon river basins. Proposed dams could result in significant losses in river connectivity in river mainstems of five of eight major systems—the Napo, Marañón, Ucayali, Beni, and Mamoré. With a newly reported 671 freshwater fish species inhabiting the Andean headwaters of the Amazon (>500 m), dams threaten previously unrecognized biodiversity, particularly among endemic and migratory species. Because Andean rivers contribute most of the sediment in the mainstem Amazon, losses in river connectivity translate to drastic alteration of river channel and floodplain geomorphology and associated ecosystem services

    Innovación para el desarrollo de productos

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    Colombia usually has been a commodities exporter country and a value-added products importer but, if this situation persists, not only the economic but also the technological gap will be maintained. Therefore, it is necessary to stress the need to innovate in the training of engineering students in design and product development, that is, to go beyond the simple extraction of raw materials to the transformation processes. To that end, this document proposes the use of not structured practices as an initial approach to develop early skills in product development. These investigative competences are strengthened and tested in the degree project, a requirement for the respective engineer´s degree. Three cases investigated are included as examples, the first is related to obtaining a natural dye from the flower of the Majagua tree, the second case in which, through the study of patents, the conditions for improving performance for the production of sodium  percarbonate are obtained and finally the conditions for obtaining an avocado oil gourmet type are determined.Colombia ha sido normalmente un país exportador de materias primas e importador de productos con valor agregado, pero si está situación persiste se mantendrá la brecha no sólo económica sino tecnológica. Por lo tanto, es necesario insistir en la necesidad de entrenar a los estudiantes de ingeniería en el diseño y desarrollo de productos, es decir, ir más allá de la simple extracción de materias primas para llegar a los procesos de transformación. Para tal efecto, en este documento se propone el empleo de las prácticas no estructuradas como una aproximación inicial al desarrollo de las habilidades iniciales en el desarrollo de productos. Estas competencias investigativas se fortalecen y ponen a prueba en el desarrollo de los proyectos de grado, requisitos necesarios para obtener los respectivos grados de ingenieros.Se incluyen, a modo de ejemplo, tres casos investigados, relativos a la obtención de un colorantes de la flor del árbol de Majagua, otro caso en el cual, a partir del estudio de patentes, se pueden obtener las condiciones para mejorar el rendimiento en la producción de percarbonato de sodio y finalmente se determinan las condiciones para obtener el aceite de aguacate tipo gourmet

    Registered replication report on Fischer, Castel, Dodd, and Pratt (2003)

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    The attentional spatial-numerical association of response codes (Att-SNARC) effect (Fischer, Castel, Dodd, & Pratt, 2003)—the finding that participants are quicker to detect left-side targets when the targets are preceded by small numbers and quicker to detect right-side targets when they are preceded by large numbers—has been used as evidence for embodied number representations and to support strong claims about the link between number and space (e.g., a mental number line). We attempted to replicate Experiment 2 of Fischer et al. by collecting data from 1,105 participants at 17 labs. Across all 1,105 participants and four interstimulus-interval conditions, the proportion of times the effect we observed was positive (i.e., directionally consistent with the original effect) was .50. Further, the effects we observed both within and across labs were minuscule and incompatible with those observed by Fischer et al. Given this, we conclude that we failed to replicate the effect reported by Fischer et al. In addition, our analysis of several participant-level moderators (finger-counting habits, reading and writing direction, handedness, and mathematics fluency and mathematics anxiety) revealed no substantial moderating effects. Our results indicate that the Att-SNARC effect cannot be used as evidence to support strong claims about the link between number and space

    Traditional Excluding Forces: A Review of the Quantitative Literature on the Economic Situation of Indigenous Peoples, Afro-Descendants, and People Living with Disability

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    Effectiveness of a Messenger RNA Vaccine Booster Dose Against Coronavirus Disease 2019 Among US Healthcare Personnel, October 2021-July 2022

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    BACKGROUND: Protection against symptomatic severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection (coronavirus disease 2019 [COVID-19]) can limit transmission and the risk of post-COVID conditions, and is particularly important among healthcare personnel. However, lower vaccine effectiveness (VE) has been reported since predominance of the Omicron SARS-CoV-2 variant. METHODS: We evaluated the VE of a monovalent messenger RNA (mRNA) booster dose against COVID-19 from October 2021 to June 2022 among US healthcare personnel. After matching case-participants with COVID-19 to control-participants by 2-week period and site, we used conditional logistic regression to estimate the VE of a booster dose compared with completing only 2 mRNA doses \u3e150 days previously, adjusted for multiple covariates. RESULTS: Among 3279 case-participants and 3998 control-participants who had completed 2 mRNA doses, we estimated that the VE of a booster dose against COVID-19 declined from 86% (95% confidence interval, 81%-90%) during Delta predominance to 65% (58%-70%) during Omicron predominance. During Omicron predominance, VE declined from 73% (95% confidence interval, 67%-79%) 14-60 days after the booster dose, to 32% (4%-52%) ≥120 days after a booster dose. We found that VE was similar by age group, presence of underlying health conditions, and pregnancy status on the test date, as well as among immunocompromised participants. CONCLUSIONS: A booster dose conferred substantial protection against COVID-19 among healthcare personnel. However, VE was lower during Omicron predominance, and waning effectiveness was observed 4 months after booster dose receipt during this period. Our findings support recommendations to stay up to date on recommended doses of COVID-19 vaccines for all those eligible

    Differential cross section measurements for the production of a W boson in association with jets in proton–proton collisions at √s = 7 TeV

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    Measurements are reported of differential cross sections for the production of a W boson, which decays into a muon and a neutrino, in association with jets, as a function of several variables, including the transverse momenta (pT) and pseudorapidities of the four leading jets, the scalar sum of jet transverse momenta (HT), and the difference in azimuthal angle between the directions of each jet and the muon. The data sample of pp collisions at a centre-of-mass energy of 7 TeV was collected with the CMS detector at the LHC and corresponds to an integrated luminosity of 5.0 fb[superscript −1]. The measured cross sections are compared to predictions from Monte Carlo generators, MadGraph + pythia and sherpa, and to next-to-leading-order calculations from BlackHat + sherpa. The differential cross sections are found to be in agreement with the predictions, apart from the pT distributions of the leading jets at high pT values, the distributions of the HT at high-HT and low jet multiplicity, and the distribution of the difference in azimuthal angle between the leading jet and the muon at low values.United States. Dept. of EnergyNational Science Foundation (U.S.)Alfred P. Sloan Foundatio

    Penilaian Kinerja Keuangan Koperasi di Kabupaten Pelalawan

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    This paper describe development and financial performance of cooperative in District Pelalawan among 2007 - 2008. Studies on primary and secondary cooperative in 12 sub-districts. Method in this stady use performance measuring of productivity, efficiency, growth, liquidity, and solvability of cooperative. Productivity of cooperative in Pelalawan was highly but efficiency still low. Profit and income were highly, even liquidity of cooperative very high, and solvability was good
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