638 research outputs found

    Implicaciones genéticas de nuevos datos de Sr y Nd de rocas intrusivas del Arco Laramide en el Norte de Sonora, México

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    The Laramide Intrusive Arc constitutes a wide intrusive belt broadly parallel to the actual Sonora coastline. It was formed by the subduction of the Farallon Plate beneath the North-American Plate during the Late Cretaceous-Early Tertiary period. New isotopic data on rocks of this arc show initial 87Sr/86Sr and eNd isotopic values of 0.7066 to 0.7070 and -5 to -6, respectively, for two samples from Bacanora area; as well as 0.7074 to 0.7081 and -3 to -5.5 respectively, for five samples from Cananea, Mariquita and La Caridad areas. Isotopic ages were determined by U/Pb in zircons (95 Ma) and Ar/Ar in potassic feldspar (56 to 71 Ma) from a quartz monzonite porphyry, and by Ar/Ar in potassic feldspar (56 Ma) from another plutonic granodiorite, both from Bacanora. Initial 87Sr/86Sr and eNd values for samples reported in this study suggest that the Laramidic magmas had a large influence from the Proterozoic basement in northeastern Sonora. Four different isotopic zones are proposed for Sonora, according with Sr-Nd data of laramidic rocks and the substratum intruded.El Arco Intrusivo Laramide constituye un amplio cinturón de rocas intrusivas orientado burdamente paralelo a la costa actual de Sonora. Este cinturón se originó por la subducción de la Placa Farallón bajo la Placa de Norteamérica durante el período Cretácico Tardío – Terciario Temprano. Nuevos datos isotópicos en rocas de este arco indican valores iniciales de 87Sr/86Sr y de eNd de 0.7066 a 0.7070 y -5 a -6, respectivamente, para dos muestras del área de Bacanora; así como de 0.7074 a 0.7081 y -3 a -5.5, respectivamente, para cinco muestras de las áreas de Cananea, Mariquita y La Caridad. Se determinaron también edades isotópicas por U/Pb en zircones (95 Ma) y Ar/Ar en feldespato potásico (56 a 71 Ma) para un pórfido de monzonita de cuarzo, y por Ar/Ar en feldespato potásico (56 Ma) para otra granodiorita plutónica, ambas de Bacanora. Los valores iniciales de 87Sr/86Sr y eNd para las muestras reportadas en este estudio, sugieren que los magmas laramídicos tuvieron gran influencia del basamento proterozoico en el noreste de Sonora. Cuatro diferentes zonas isotópicas son propuestas para Sonora, de acuerdo con los datos de Sr-Nd de las rocas laramídicas y el sustrato intrusionado

    Identification of an alternative G{alpha}q-dependent chemokine receptor signal transduction pathway in dendritic cells and granulocytes

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    CD38 controls the chemotaxis of leukocytes to some, but not all, chemokines, suggesting that chemokine receptor signaling in leukocytes is more diverse than previously appreciated. To determine the basis for this signaling heterogeneity, we examined the chemokine receptors that signal in a CD38-dependent manner and identified a novel "alternative" chemokine receptor signaling pathway. Similar to the "classical" signaling pathway, the alternative chemokine receptor pathway is activated by G{alpha}i2-containing Gi proteins. However, unlike the classical pathway, the alternative pathway is also dependent on the Gq class of G proteins. We show that G{alpha}q-deficient neutrophils and dendritic cells (DCs) make defective calcium and chemotactic responses upon stimulation with N-formyl methionyl leucyl phenylalanine and CC chemokine ligand (CCL) 3 (neutrophils), or upon stimulation with CCL2, CCL19, CCL21, and CXC chemokine ligand (CXCL) 12 (DCs). In contrast, G{alpha}q-deficient T cell responses to CXCL12 and CCL19 remain intact. Thus, the alternative chemokine receptor pathway controls the migration of only a subset of cells. Regardless, the novel alternative chemokine receptor signaling pathway appears to be critically important for the initiation of inflammatory responses, as G{alpha}q is required for the migration of DCs from the skin to draining lymph nodes after fluorescein isothiocyanate sensitization and the emigration of monocytes from the bone marrow into inflamed skin after contact sensitization

    Planteamiento metodológico para lograr la eficiencia hídrica sustentable. Estudio de caso: unidad habitacional Tepic, Nayarit

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    El presente trabajo consiste en un estudio acerca de la problemática que enfrentan los conjuntos habitacionales en Tepic Nayarit, para abastecer la creciente demanda de la población. Se parte de cuatro aspectos fundamentales que un sistema de agua potable debe cumplir, de acuerdo a la Comisión Nacional del Agua. Referido a un estudio de caso, en donde se hizo un análisis del contexto en relación con el suministro y presión del agua, análisis del usuario en relación con el consumo de agua, que incluye un monitoreo de gasto actual y otro con dispositivos ahorradores. Al final se establecen escenarios para mejorar el abastecimiento continuo de agua, y para conocer el efecto que tiene la implementación de dispositivos ahorradores. La eficiencia hídrica promovida en estas viviendas ayudará a garantizar el abastecimiento continuo, promover el uso adecuado y consiente del agua, fomentar hábitos de consumo responsable y ayudar a preservar los mantos acuíferos de la ciudad.ITESO, A.C

    The Whooping Crane in Mexico: Past, Present, and Future?

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    We reviewed ornithological, historic, anthropological, and archaeological records for evidence of whooping cranes (Grus americana) in Mexico. Records of whooping cranes in Mexico span 88 years (1863-1951) and cluster in 3 areas. Wintering records come from the northern highlands (Durango, and possibly Chihuahua), the central highlands (Guanajuato, Jalisco), and northeastern Tamaulipas, where the bird was also found in summer and might have bred. Later records (1970’s and 1980’s) of whooping cranes in the northern highlands are from individual birds released into the experimental migratory population that formerly migrated from Idaho to New Mexico, USA. Many of the wetlands used by whooping cranes remain and, though faced with a variety of threats, are conservation priority areas and some are already protected. We suggest 3 scenarios by which whooping cranes might return to winter in Mexico. The first 2 involve dispersal by birds wintering at the Aransas National Wildlife Refuge, Texas, USA, by either population growth or ecosystem changes or degradation (e.g., climate change, reduced freshwater inflows) at the refuge. Finally, reintroduction of a migratory population might target part of Mexico as a wintering area. We encourage investigation of wetlands in Mexico, especially in northeastern Tamaulipas for their potential as future wintering areas. Our preliminary survey of historic Spanish language publications covering the 1500’s to early 1600’s found clear references to cranes in which, for example, cranes are described feeding with geese in grain fields. Cranes are mentioned in accounts of the DeSoto and Coronado expeditions as well as the travels of Bishop Alonso de la Mota y Escobar. Unfortunately, these accounts do not adequately describe the birds for species identification. Only, the Florentine Codex by Fray Bernardino de Sahagun provides a description of the sandhill crane (G. canadensis) from near Mexico City at the time of Spanish conquest of the Aztecs. Continued searches of early Spanish language publications might yield more information of the historic distribution of cranes in Mexico

    Characterization of Burkholderia rhizoxinica and B. endofungorum Isolated from Clinical Specimens

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    Eight isolates submitted to CDC from 1989 to 2006 from clinical specimens were initially identified as members of the genus Burkholderia based on preliminary cellular fatty acid analysis and/or 16S rRNA gene sequencing. With the recent descriptions of the new species B. rhizoxinica and B. endofungorum, which are considered endosymbiotic bacteria in Rhizopus microsporus fungi, we now identify seven of these clinical isolates as B. rhizoxinica and one as B. endofungorum based on biochemical testing, 16s rRNA, and DNA-DNA hybridization results. We also further characterize these isolates by assessing toxin production and/or by multiple locus sequence typing

    El sistema skarn-epitermal de Zn–(Pb–Cu) de Velardeña, Durango (México): Nuevos datos fisicoquímicos de los procesos de mineralización

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    [eng] The Velardeña mining district is economically the most important of Durango state. The ore deposits occur in different skarn zones developed within the intrusive contact between Mesozoic limestones and Eocene granitic stocks and dikes. The most important ore deposits are related to the Santa María dike and Reyna de Cobre porphyritic stock (separated from each other by 10 km). They occur as irregularly shaped replacement masses developed near the intrusive contact and have a skarn paragenesis dominated by calc-silicates and sulfides. The mineral assemblages show replacement textures and are dominated by calcic clinopyroxene (Di97-53Hd42-02Jh04-01) and garnet (Ad100-57Grs43-00) in the exoskarn, with wollastonite particularly abundant in the endoskarn. Hydrous silicates are actinolite, epidote, and chlorite, whereas sulfides include pyrite, sphalerite, pyrrhotite, galena, chalcopyrite, and sulfosalts. Scheelite, hematite, quartz, and calcite are also present. According to sphalerite geobarometry, the skarns formed at hypabyssal depths (~3-4 km). They developed by a succession of replacive mineralizing events, including (a) a prograde stage at temperatures from ≥470 to 335 °C in conditions of low f (CO2), followed by (b) a retrograde stage from 335 to 220 °C. There was a general increase in f (O2), accompanying the temperature decline during the formation of the system, which accounts for a process of mixing with cooler, oxidizing, and dilute water. During the retrograde stage, wollastonite, calcic garnet and clinopyroxene formed. On the other hand, hydrous silicates, sulfides, sulfosalts, scheelite, and hematite crystallized during the retrograde stage. Skarn mineralization is crosscut by veins of calcite, fluorite, adularia, and sphalerite. The vein mineralization formed at temperatures below 200 °C. The different ore deposits of Velardeña constitute a telescoped skarn-epithermal mineral system.[spa]El distrito minero Velardeña es económicamente el más importante del estado de Durango. En él, las mineralizaciones comprenden diferentes zonas de skarn, desarrolladas entre el contacto de calizas mesozoicas, stocks y diques del Eoceno. Los depósitos de Velardeña más importantes están relacionados al dique Santa María, y el stock porfídico Reyna de Cobre (separados entre sí ~10 km). La mineralización ocurre como reemplazamiento, formando cuerpos irregulares cerca del contacto con los intrusivos, caracterizados por una paragénesis típica de skarn (calcisilicatos y sulfuros). Las asociaciones minerales muestran texturas de reemplazo dominados por clinopiroxeno cálcico (Di53Hd42-02Jh04-01) y granate (Ad100-57Grs43-00) en el exoskarn, y wollastonita particularmente abundante en el endoskarn. Los hidrosilicatos son actinolita, epidota y clorita; los sulfuros incluyen pirita, esfalerita, pirro tita, galena, calcopirita y sulfosales. Scheelita, hematita, cuarzo y calcita también están presentes. El geobarómetro de esfalerita estima que las mineralizacionestipo skarn de Velardeña se formaron a profundidades hipabisales (~ 3-4 km). La mineralización metálica se desarrolló por una sucesión de eventos de reemplazamiento, que incluyen (a) una etapa prógrada a ≥470 a 335 °C y baja f(CO ), seguida por (b) la etapa retrógrada de 335 a 2202°C. Hubo un aumento general de f(O ), durante el descenso de temperatura en laformación del yacimiento, debido a la mezcla de fluidos mineralizantes con agua más fría, oxidante y diluida. Durante la etapa retrógrada, se formaron wollastonita, granate cálcico y clinopiroxeno. La etapa prógrada dio lugar a la formación de hidrosilicatos, sulfuros (inclu- yendo sulfosales), scheelita y hematita. Además de las mineralizaciones tipo skarn en Velardeña, hay vetas epitermales de calcita, fluorita, adularia y esfalerita, cortando los calcosilicatos. La mineralización en estas vetas se estima que se formó a <200 °C. Por ello, es plausible proponer que los depósitos minerales que conforman el distrito minero Velardeña constituyen un sistema skarn-epitermal telescópeado

    Interleukin 12p40 is required for dendritic cell migration and T cell priming after Mycobacterium tuberculosis infection

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    Migration of dendritic cells (DCs) to the draining lymph node (DLN) is required for the activation of naive T cells. We show here that migration of DCs from the lung to the DLN after Mycobacterium tuberculosis (Mtb) exposure is defective in mice lacking interleukin (IL)-12p40. This defect compromises the ability of IL-12p40–deficient DCs to activate naive T cells in vivo; however, DCs that express IL-12p40 alone can activate naive T cells. Treatment of IL-12p40–deficient DCs with IL-12p40 homodimer (IL-12(p40)2) restores Mtb-induced DC migration and the ability of IL-12p40–deficient DCs to activate naive T cells. These data define a novel and fundamental role for IL-12p40 in the pathogen-induced activation of pulmonary DCs

    Metodología de análisis de sostenibilidad de materiales producidos en Jalisco, de la Materioteca del ITESO

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    Se presenta el proyecto de investigación y los primeros resultados de la metodología de análisis de sostenibilidad en materiales producidos dentro del estado de Jalisco, con base en normas internacionales para la evaluación del proceso industrial en la fabricación de materiales. A partir de investigación documental y de campo, se observan variables de impacto ambiental, social y económico, por medio del Análisis de Ciclo de Vida y del uso de software especializado, se establece el impacto ambiental en CO2, Huella Hídrica y Huella de Carbono y otras huellas de la dimensión ambiental; en los temas sociales se analizan criterios como la seguridad laboral, la capacitación, el desarrollo y la responsabilidad social de las empresas productoras; en los temas económicos se analizan aspectos de la producción local y artesanal, o la producción en cooperativas y el comercio justo. Con lo anterior se desarrollan fichas físicas de materiales que muestran sus características de desempeño sostenible, en un formato compatible con materiotecas de otros países. Se presentan también ejemplos de resultados y se concluye sobre las oportunidades de mejora en los procesos productivos locales y la prospectiva de esta investigación, entre ellas el aterrizaje de resultados a un contexto social comprensible, mejoramiento de la información y de los procesos productivos de los materiales locales, así como la creación de una estrategia integral entre productores, dependencias gubernamentales e instituciones de educación superior para el mejoramiento de estos procesos

    The changing nature of shelf-break exchange revealed by the OOI Pioneer Array

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    Author Posting. © The Oceanography Society, 2018. This article is posted here by permission of The Oceanography Society for personal use, not for redistribution. The definitive version was published in Oceanography 31, no. 1 (2018): 60–70, doi:10.5670/oceanog.2018.110.Although the continental shelf and slope south of New England have been the subject of recent studies that address decadal-scale warming and interannual variability of water mass properties, it is not well understood how these changes affect shelf-break exchange processes. In recent years, observations of anomalous shelf and slope conditions obtained from the Ocean Observatories Initiative Pioneer Array and other regional observing programs suggest that onshore intrusions of warm, salty waters are becoming more prevalent. Mean cross-shelf transects constructed from Pioneer Array glider observations collected from April 2014 through December 2016 indicate that slope waters have been warmer and saltier. We examine shelf-break exchange events and anomalous onshore intrusions of warm, salty water associated with warm core rings located near the shelf break in spring 2014 and winter 2017 using observations from the Pioneer Array and other sources. We also describe an additional cross-shelf intrusion of ring water in September 2014 to demonstrate that the occurrence of high-salinity waters extending across the continental shelf is rare. Observations from the Pioneer Array and other sources show warm core ring and Gulf Stream water masses intrude onto the continental shelf more frequently and penetrate further onshore than in previous decades.GG, WZ, RT, and MD were supported by the National Science Foundation under grant OCE-1657853. WZ was also supported by grant OCE-1634965. JP is grateful for the support of the Woods Hole Oceanographic Institution Summer Student Fellow Program. AMM was supported by a grant from the MacArthur Foundation. GG and AMM were also supported by a grant from the van Beuren Charitable Foundation for collection and analysis of hydrographic data collected by the CFRF Shelf Research Fleet

    Assessment and visualization of phenome-wide causal relationships using genetic data:an application to dental caries and periodontitis

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    Hypothesis-free Mendelian randomization studies provide a way to assess the causal relevance of a trait across the human phenome but can be limited by statistical power, sample overlap or complicated by horizontal pleiotropy. The recently described latent causal variable (LCV) approach provides an alternative method for causal inference which might be useful in hypothesis-free experiments across human phenome. We developed an automated pipeline for phenome-wide tests using the LCV approach including steps to estimate partial genetic causality, filter to a meaningful set of estimates, apply correction for multiple testing and then present the findings in a graphical summary termed causal architecture plot. We apply this pipeline to body mass index (BMI) and lipid traits as exemplars of traits where there is strong prior expectation for causal effects, and to dental caries and periodontitis as exemplars of traits where there is a need for causal inference. The results for lipids and BMI suggest that these traits are best viewed as contributing factors on a multitude of traits and conditions, thus providing additional evidence that supports viewing these traits as targets for interventions to improve health. On the other hand, caries and periodontitis are best viewed as a downstream consequence of other traits and diseases rather than a cause of ill health. The automated pipeline is implemented in the Complex-Traits Genetics Virtual Lab ( https://vl.genoma.io ) and results are available in https://view.genoma.io . We propose causal architecture plots based on phenome-wide partial genetic causality estimates as a new way visualizing the overall causal map of the human phenome
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