460 research outputs found

    Pleistocene climate fluctuations drove demographic history of African golden wolves (Canis lupaster)

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    Pleistocene climate change impacted entire ecosystems throughout the world. In the northern hemisphere, the distribution of Arctic species expanded during glacial periods, while more temperate and mesic species contracted into climatic refugia, where isolation drove genetic divergence. Cycles of local cooling and warming in the Sahara region of northern Africa caused repeated contractions and expansions of savannah‐like environments which connected mesic species isolated in refugia during interglacial times, possibly driving population expansions and contractions; divergence and geneflow in the associated fauna. Here, we use whole genome sequences of African golden wolves (Canis lupaster), a generalist mesopredator with a wide distribution in northern Africa to estimate their demographic history and past episodes of geneflow. We detect a correlation between divergence times and cycles of increased aridity‐associated Pleistocene glacial cycles. A complex demographic history with responses to local climate change in different lineages was found, including a relict lineage north of the High Atlas Mountains of Morocco that has been isolated for more than 18,000 years, possibly a distinct ecotype.CS was supported by a PhD fellowship from Programa Internacional de Becas “La Caixa-Severo Ochoa” of the Spanish Ministerio de Economía y Competitividad and La Caixa bank (BES-2015-074331). This project was funded by the Frontera grant P18-FR-5099 from the Junta de Andalucia. EBD-CSIC received support from the Spanish Ministry of Economy and Competitiveness under the ‘Centro de Excelencia Severo Ochoa 2013-2017’ program, SEV-2012-0262

    Desarrollo de herramientas de búsqueda en los archivos históricos de la CompañÍa de Jesús

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    El trabajo de los historiadores es pesado y difícil ya que consiste, fundamentalmente, en la localización, análisis e interpretación de documentos antiguos. Estos documentos, cuando están disponibles para su consulta, deben ser leídos uno por uno y todas las posibles referencias cruzadas, revisadas una por una. La Compañía de Jesús llegó a la Nueva España en el siglo XV y trabajó en colegios, misiones, parroquias y hospitales a lo largo de todo el continente hasta la expulsión de la Orden en 1767. Durante este tiempo, la Compañía de Jesús puso en marcha un sistema de comunicación conocido como las Cartas Anuales o Cartas Annuas que el Provincial enviaba al General de la Compañía en Roma. Cada una de las Cartas Anuales relataba las actividades llevadas a cabo por miembros de la Compañía. Para ayudarse a redactar cada Carta y con el fin de circular la información en toda la Provincia de la Nueva España, cada uno de los encargados de las obras enviaba al Provincial una o varias cartas conocidas como Puntos de Annua. La Compañía de Jesús, junto con el Archivo General de la Nación y el Instituto Nacional de Antropología e Historia se dio a la tarea de recopilar todas las Cartas Anuales escritas desde que los jesuitas llegaron a la Nueva España hasta su expulsión en 1767. Esta búsqueda resultó en más de 13000 folios que debieron paleografiarse para ayudar a la investigación histórica sobre la Compañía de Jesús. Como resultado de este trabajo de recuperación y paleografía y para facilitar el acceso y manejo de los documentos, se decidió crear una herramienta informática que ofreciera a los investigadores un motor de búsqueda para hacer referencias cruzadas rápida y fácilmente, así como el acceso a los documentos a través de índices temáticos. El desarrollo de esta herramienta presentó varios problemas técnicos que se han ido solucionando. Por ejemplo, la necesidad de que los documentos en formato electrónico siguieran fielmente las reglas de la paleografía. Este requerimiento hizo necesaria la realización de un filtro para manipular los archivos en formato XML. Se desarrolló también la interfaz gráfica para acceder a los índices temáticos y el motor de búsqueda para realizar referencias cruzadas en una o varias palabras, continuas o discontinuas en el texto del documento. La herramienta ha sido bien recibida por los investigadores y se ha decido aumentarla con algoritmos de Text-Mining para aumentar las capacidades de la búsqueda así como la generación de referencias cruzadas entre los documentos.ITESO, A.C

    Bayesian estimation of incomplete data using conditionally specified priors

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    In this paper, a class of conjugate prior for estimating incomplete count data based on a broad class of conjugate prior distributions is presented. The new class of prior distributions arises from a conditional perspective, making use of the conditional specification methodology and can be considered as the generalisation of the form of prior distributions that have been used previously in the estimation of in- complete count data well. Finally, some examples of simulated and real data are given

    Steady-State 3D Trapping and Manipulation of Microbubbles Using Thermocapillary

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    [EN] An experimental and theoretical study on the 3D trapping and manipulation of microbubbles by means low power laser-induced temperature gradients induced in ethanol by bulk light absorption (¿ 1550 nm) is presented. Two optical fibers were used: One for bubble generation (OFG) and the other for both trapping and manipulation (OFT). Light from a Q-switched pulsed laser (¿ 532 nm and pulse width ¿p 5 ns) propagates in fiber OFG and gets absorbed at silver nanoparticles (AgNPs), previously photodeposited, at the distal end of a fiber optic core, generating the microbubbles. In the fiber OFT, light of low power CW laser was used to trap and manipulate the bubbles by thermocapillary induced by light bulk absorption in ethanol. The microbubble generated on OFG migrates toward the fiber OFT. The equilibrium between the buoyancy force FB, drag force FD and the Marangoni force (also known as thermocapillary force) FM gives rise to a 3D stably trapping and manipulation of the microbubble for the best time to our best knowledge.This work was supported by CONACyT through the grant number A1-S-28440.Muñoz-Pérez, FM.; Ortega-Mendoza, JG.; Padilla-Vivanco, A.; Toxqui-Quitl, C.; Sarabia-Alonso, J.; Ramos-García, R. (2020). Steady-State 3D Trapping and Manipulation of Microbubbles Using Thermocapillary. Frontiers in Physics. 8. https://doi.org/10.3389/fphy.2020.585590

    Effect of Defoliation Frequency on Forage Yield from Intensive Silvopastoral Systems Compared to a Monoculture Grassland

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    Livestock production in the tropical regions of the world faces serious constraints as a result of climate change. Monoculture based pastures require the use of large amounts of nitrogen fertilizers to sustain production throughout the year. In general terms, tropical grasses are of low quality and when consumed by ruminant species, contribute to the emission of greenhouse gases (methane, carbon dioxide and nitrous oxide) (Herrero et al. 2009; Place et al. 2009). The establishment of intensive silvopastoral systems (iSPS) with associated shrubs legumes and grasses can increase the yield and quality of forage as well as fixation and transfer of atmospheric nitrogen (N) (Murgueitio et al. 2011). Therefore, the costs of nitrogen fertilizers and the emissions of greenhouse gases under practical conditions can be reduced. The intensive silvopastoral system is a kind of agroforestal practice that it is environmentally friendly and at the same time improves productivity of livestock systems. However, several aspects of its management have not been fully evaluated. This is the case of the response to defoliation, which is an important management factor associated to the overall biomass productivity (Solorio 2005)

    Determination of dichlobenil and its major metabolite (BAM) in onions by PTV–GC–MS using PARAFAC2 and experimental design methodology

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    The optimization of a GC–MS analytical procedure which includes derivatization, Quick Easy Cheap Effective Rugged and Safe (QuEChERS) and programmed temperature vaporization (PTV) using design of experiments is performed to determine 2,6-dichlorobenzonitrile (dichlobenil) and 2,6-dichlorobenzamide (BAM) in onions, using 3,5-dichlorobenzonitrile and 2,4-dichlorobenzamide as internal standards. The use of a central composite design and two D-optimal designs, together with the desirability function, makes it possible to significantly reduce the economic, time and environmental cost of the study. The usefulness of PARAFAC2 for solving problems as the interference of unexpected derivatization artifacts unavoidably linked to some derivatization agents, or the presence of coeluents from the complex matrix, which share m/z ratios with the target compounds, is shown. The limits of decision (CCα) of the optimized procedure, 5.00 μg kg− 1 for dichlobenil and 1.55 μg kg− 1 for BAM (α = 0.05), are below the maximum residue limit (MRL) established by the EU for dichlobenil (20 μg kg− 1) in this commodity.Ministerio de Economía y Competitividad (CTQ2011-26022) and Junta de Castilla y León (BU108A11-2

    Moleculars biomarkers in pediatric rhabdomyosarcoma: from molecular biology to clinical application

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    El rabdomiosarcoma (RMS) es el tumor ma-ligno de partes blandas más común en la infancia. Se dis-tinguen principalmente dos subtipos histológicos: embrio-nario (RMSe) y alveolar (RMSa), teniendo el primero mejor pronóstico que el segundo. Estudios recientes han identifi-cado alteraciones moleculares (transcriptos de fusión PAX3 y PAX7) en el 80% de los RMSa. Estos transcriptos de fusión, además de definir el diagnóstico, le confieren propiedades biológicas al tumor independientemente del subtipo histoló-gico, que modifican su comportamiento. El estudio de estos marcadores podría ser incorporado a la estratificación de riesgo (edad, tamaño tumoral, tipo histológico, localización) al comprobarse que los mismos confieren un valor pronós-tico adverso. Objetivos: el objetivo del siguiente estudio fue implementar la búsqueda de los transcriptos de fusión PAX3 y PAX7 en las muestras de pacientes diagnosticados con RMS. Se plan-teó, también, el estudio de la asociación entre los marcado-res moleculares con la estratificación de riesgo y la respuesta terapéutica de pacientes pediátricos con RMS

    Calorie Restriction Improves Physical Performance and Modulates the Antioxidant and Inflammatory Responses to Acute Exercise

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    Our aim was to characterize the effects of calorie restriction on the anthropometric characteristics and physical performance of sportsmen and to evaluate the effects of calorie restriction and acute exercise on mitochondria energetics, oxidative stress, and inflammation. Twenty volunteer taekwondo practitioners undertook a calorie restriction of 30–40% on three alternate days a week for one month. Eleven volunteer sportsmen participated as controls. Both groups performed an energy efficiency test to evaluate physical performance, and samples were taken before and after exercise. The total weight of participants significantly decreased (5.9%) after calorie restriction, while the efficiency of work and the contributions of fat to obtain energy were enhanced by calorie restriction. No significant differences induced by acute exercise were observed in individual non-esterified fatty acid percentage or oxidative stress markers. Calorie restriction downregulated the basal gene expression of nitric oxide synthase, antioxidant enzymes, mitochondrial uncoupling proteins, and repairing stress proteins, but it enhanced the expression of sirtuins in peripheral blood mononuclear cells. In conclusion, one month of calorie restriction decreases body weight and increases physical performance, enhancing energy efficiency, moderating the antioxidant and inflammatory basal gene expression, and influencing its response to acute exercise.This research was funded by Acción Estratégica en Salud del Ministerio de Ciencia e Innovación DPS2008-07033-C03-03, Program of Promotion of Biomedical Research and Health Sciences, Projects 11/01791, Red Predimed-RETIC RD06/0045/1004, CIBEROBN CB12/03/30038, and Balearic Island Government (35/2011 and 23/2012) and FEDER funds. X.C. was funded by a FOLIUM program of Institut d’Investigació Sanitària de les Illes Balears. M.H.L. was founded by APOSTD/2017/023 fellowship from Generalitat Valenciana to APS

    Effect of immunocastration on behaviour and blood parameters (cortisol and testosterone) of Holstein bulls

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    To evaluate the effect that immunocastration has on behaviour, testosterone and cortisol levels of feedlot Holstein bulls, 720 intact animals aged between 7 and 8 months, weighing 232±1.19 kg were randomly assigned to two treatments: immunocastration using the Bopriva vaccine and a placebo (360 animals per treatment). The bulls were slaughtered at day 239 of treatment. Animals were vaccinated on days 1, 21, 101, and 181, and on those same days testosterone levels were measured; while cortisol, glucose and creatin kinase measurements were done on day 181 and during exanguination at slaughter. Sexual, aggressive and social behaviours were evaluated and it was found that intact bulls showed a higher average of head butts, mounting, threats, flehmen sign and sniffing (P<0.05), no differences were found for vocalisations, lowering of the head and grooming (P>0.05). Testosterone levels in intact bulls remained at 0.47ng/mL throughout the study, however, by day 181 differences (P<0.05) were observed in immunised bulls, with values of 0.22ng/mL. At slaughter, testosterone levels were 0.21 ± 0.06 ng/mL in immunocastrated bulls and 0.54 ± 0.06 ng/mL in the placebo group. The use of immunocastration with Bopriva has shown to be effective to reduce testosterone, sexual and aggressive behaviours on Holstein bulls

    Multi-technical approach for the characterization of polychrome decorative surfaces at Spanish Mission Churches in Nueva Vizcaya (Chihuahua, Mexico)

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    An interdisciplinary and multi-institutional group of science and art conservation specialists has provided new insight into the painting materials used in the polychrome walls and wooden ceilings in four seventeenth century Spanish colonial churches of Nueva Vizcaya (Chihuahua, Mexico). A multi-analytical study of the decorative surfaces was performed in situ using spectroscopic approaches (XRF, FORS), False Colour Infrared Reflectography - IRFC, as well as micro sampling (ATR-FTIR, LM, GC/MS). A survey of natural resources and study (ATR-FTIR, LM) was carried out to elucidate the natural occurrence of a select number of materials in the surrounding areas of the churches. The present paper presents a multi-analytical study and characterization of green, red-orange and black colour pigments and binders selected from the decorative surfaces. The aim of this study is to highlight relationships between local materials and those from the original polychrome ceilings, in order to understand the material and technological influences that converged in the Spanish colonial architecture of northern Mexico
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