1,408 research outputs found

    NASA applications project in Miami County, Indiana

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    The study site selection is intended to serve all of the different research areas within the project, i.e., soil conditions, soil management, etc. There are seven major soil associations or soils formed on similar landscapes in the Miami Co., and over 38 soil series that were mapped. Soil sampling was conducted in some sites because of its variability in soils and cover types, variable topography, and presence of erosion problems. Results from analysis of these soil data is presented

    Effects of livestock pressure and vegetation cover on the spatial and temporal structure of soil microarthropod communities in Iberian rangelands

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    Forests, including their soils, play an important role since they represent a large reservoir of biodiversity. Current studies show that the diversity of soil fauna provides multiple ecosystem functions and services across biomes. However, anthropogenic practices often pose a threat to soil fauna because of changes in land use and soil mismanagement. In these terms, rangelands in the southwest of Spain present several problems of soil degradation related to livestock activity and soil erosion, the intensity of which compromises the soil fauna's functions in the ecosystem. Therefore, the aim of this study is to evaluate the response of community metrics and the spatial distribution of soil microarthropods to livestock activity and vegetation in such ecosystems. A photo interpretation analysis of an experimental catchment used as a study area was developed to identify and classify the intensity of livestock pressure. A total of 150 soil samples were collected throughout 2018. Soil biological (CO2 efflux) and physical-chemical parameters (pH, bulk density, organic matter, and water contents), and such meteorological variables as precipitation, temperature, and evapotranspiration were considered as variables affecting the composition of microarthropod communities in terms of taxa diversity, abundances, and their adaptation to soil environment (evaluated by QBS-ar index). Results showed higher abundance of microarthropods and higher adaptation to soil environment outside the influence of trees rather than beneath tree canopies. Moreover, the classification of livestock pressure revealed by the photo interpretation analysis showed low correlations with community structure, as well as with the occurrence of well-adapted microarthropod groups that were found less frequently in areas with evidence of intense livestock activity. Furthermore, abundances and adaptations followed different spatial patterns. Due to future climate changes and increasing anthropogenic pressure, it is necessary to continue the study of soil fauna communities to determine their degree of sensitivity to such changes

    First investigation of a novel 2D position-sensitive semiconductor detector concept

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    This paper presents a first study of the performance of a novel 2D position-sensitive microstrip detector, where the resistive charge division method was implemented by replacing the metallic electrodes with resistive electrodes made of polycrystalline silicon. A characterization of two proof-of-concept prototypes with different values of the electrode resistivity was carried out using a pulsed Near Infra-Red laser. The experimental data were compared with the electrical simulation of the sensor equivalent circuit coupled to simple electronics readout circuits. The good agreement between experimental and simulation results establishes the soundness of resistive charge division method in silicon microstrip sensors and validates the developed simulation as a tool for the optimization of future sensor prototypes. Spatial resolution in the strip length direction depends on the ionizing event position. The average value obtained from the protype analysis is close to 1.2% of the strip length for a 6 MIP signal.Comment: 14 pages, 12 figure

    Las nociones de calidad percibidas por productores queseros de Tandil, Argentina: diversidad de estrategias y tensiones en procesos de desarrollo territorial

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    El partido de Tandil tiene una larga historia y tradición en la producción láctea y la elaboración de quesos. La actividad quesera en la zona comienza a mediados del siglo XIX. Tradicionales, locales y naturales son los significantes asociados a los quesos tandileros, cuyo saber hacer se ha trasmitido a través de generaciones. Desde fines de los ´90, en un contexto de crisis económica, se produce un nuevo impulso a la quesería, debido: a) a las dificultades que la crisis impuso a muchos tambos su reconversión a queseros; y b) al crecimiento de la demanda de productos artesanales causado, entre otros, por el desarrollo del turismo interno. La búsqueda de la valorización de la tipicidad de los productos de Tandil, se verifica en un conjunto de iniciativas promovidas por productores y actores locales (Denominación de Origen del Salame Tandilero, Marca “Producto tradicional Tandil”). En la construcción de la imagen y valorización del producto, interviene ciertamente la concepción de la calidad de los quesos. La calidad no es un elemento que pueda ser definido por criterios objetivos, sino que depende de las percepciones de los productores y otros actores, que se generan en relación y siempre en tensión, entre los atributos intrínsecos al alimento (sabor, aroma, color) y los atributos simbólicos. La finalidad de esta comunicación es indagar la manera en que se combinan los distintos niveles de construcción de una determinada noción de "calidad” aplicada a las queserías de base rural para poder reconocer las transformaciones que se producen en el territorio tandilense. Conceptualmente apoyaremos el análisis de caso en la corriente de pensamiento económico que propone el carácter endógeno de la calidad en la definición del producto agroalimentario. Esta noción se conoce por la teoría de las convenciones (TC) que hemos aplicado para caracterizar al universo de productores estudiados de Tandil. La metodología combinó técnicas propias de las ciencias exactas y las ciencias sociales y su triangulación. Se presentan los resultados de la idea de calidad, artesanalidad, tipicidad de los distintos tipos de productores y las tensiones resultantes entre las diferentes representaciones y las nociones normativas que las contextualizan.productos típicos, convenciones de calidad, valorización, Agribusiness, Agricultural and Food Policy, Community/Rural/Urban Development, Food Consumption/Nutrition/Food Safety, Labor and Human Capital,

    Exploring the evolution and terrestrialization of scorpions (Arachnida: Scorpiones) with rocks and clocks

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    This is the final version. Available on open access from Springer via the DOI in this recordScorpions (Arachnida: Scorpiones Koch, 1837) are an ancient chelicerate arthropod lineage characterised by distinctive subdivision of the opisthosoma and venomous toxicity. The crown group is represented by over 2400 extant species, and unambiguous fossil representatives are known at least from the Cretaceous Period. However, a number of extinct scorpion lineages existed in the Palaeozoic Era, many of which are of a contentious marine (or at least semi-aquatic) lifestyle, and have long caused confusion regarding the nature of arachnid terrestrialization and arachnid phylogeny more broadly. To clarify the process of terrestrialization, there is a need to marry fossil and extant scorpions in a common evolutionary framework utilising modern advances in phylogenetics. Here, we review phylogenetic hypotheses of arachnid and scorpion interrelationships, relevant advances in phylogenetic divergence time estimation and the scorpion fossil record—especially with reference to terrestrialization. In addition, we provide a list of scorpion fossil calibrations for use in molecular dating and demonstrate their utility in deriving a novel scorpion time tree using Bayesian relaxed-clock methods. Our results reveal a window of divergence from 335 to 266 Mya for the scorpion crown group, consistent with a Pangean origin of crown scorpions inferred from the biogeographical distribution of the extant fauna.Natural Environment Research Council (NERC)University of Mancheste

    RAB8, RAB10 and RILPL1 contribute to both LRRK2 kinase-mediated centrosomal cohesion and ciliogenesis deficits

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    Mutations in the LRRK2 kinase are the most common cause of familial Parkinson's disease, and variants increase risk for the sporadic form of the disease. LRRK2 phosphorylates multiple RAB GTPases including RAB8A and RAB10. Phosphorylated RAB10 is recruited to centrosome-localized RILPL1, which may interfere with ciliogenesis in a disease-relevant context. Our previous studies indicate that the centrosomal accumulation of phosphorylated RAB8A causes centrosomal cohesion deficits in dividing cells, including in peripheral patient-derived cells. Here, we show that both RAB8 and RAB10 contribute to the centrosomal cohesion deficits. Pathogenic LRRK2 causes the centrosomal accumulation not only of phosho-RAB8 but also of phospho-RAB10, and the effects on centrosomal cohesion are dependent on RAB8, RAB10 and RILPL1. Conversely, the pathogenic LRRK2-mediated ciliogenesis defects correlate with the centrosomal accumulation of both phospho-RAB8 and phospho-RAB10. LRRK2-mediated centrosomal cohesion and ciliogenesis alterations are observed in patient-derived peripheral cells, as well as in primary astrocytes from mutant LRRK2 mice, and are reverted upon LRRK2 kinase inhibition. These data suggest that the LRRK2-mediated centrosomal cohesion and ciliogenesis defects are distinct cellular readouts of the same underlying phospho-RAB8/RAB10/RILPL1 nexus and highlight the possibility that either centrosomal cohesion and/or ciliogenesis alterations may serve as cellular biomarkers for LRRK2-related PD

    A molecular palaeobiological exploration of arthropod terrestrialization

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    Understanding animal terrestrialization, the process through which animals colonized the land, is crucial to clarify extant biodiversity and biological adaptation. Arthropoda (insects, spiders, centipedes and their allies) represent the largest majority of terrestrial biodiversity. Here we implemented a molecular palaeobiological approach, merging molecular and fossil evidence, to elucidate the deepest history of the terrestrial arthropods. We focused on the three independent, Palaeozoic arthropod terrestrialization events (those of Myriapoda, Hexapoda and Arachnida) and showed that a marine route to the colonization of land is the most likely scenario. Molecular clock analyses confirmed an origin for the three terrestrial lineages bracketed between the Cambrian and the Silurian. While molecular divergence times for Arachnida are consistent with the fossil record, Myriapoda are inferred to have colonized land earlier, substantially predating trace or body fossil evidence. An estimated origin of myriapods by the Early Cambrian precedes the appearance of embryophytes and perhaps even terrestrial fungi, raising the possibility that terrestrialization had independent origins in crown-group myriapod lineages, consistent with morphological arguments for convergence in tracheal systems. This article is part of the themed issue ‘Dating species divergences using rocks and clocks’.© 2016 The Authors. Published by the Royal Society under the terms of the Creative Commons Attribution License http://creativecommons.org/licenses/by/4.0/, which permits unrestricted use, provided the original author and source are credited
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