177 research outputs found

    El juego de chuncana entre los chimú. Un tablero de madera que prueba la hipótesis de Erland Nordenskiöld

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    A principios del siglo XX el antropólogo sueco Nordenskiöld describe un tipo de juego que los indígenas del Chaco practican al final de la época de lluvias, en el mes de marzo. Nordenskiöld plantea la hipótesis de que tal juego es de origen andino. Añadiendo nuevas pruebas lingüísticas y etnológicas, así como la aplicabilidad de las reglas del referido juego del Chaco, la autora trata de demostrar, basándose en un estudio iconográfico, que un tablero de juego de la época chimú que se encuentra en el Museo Linden, Alemania, podría probar la hipótesis de Nordenskiöld.Au début du 20ème siècle l’anthropologue suédois Erland Nordenskiöld décrivit une forme de jeu pratiqué par les indigènes de la région de Chaco à la fin de la saison des pluies au mois de mars. Nordenskiöld soutient l’hypothèse que ce jeu pourrait avoir ses origines dans les Andes. L’auteur établit la probabilité de cette hypothèse en se basant sur l’analyse iconographique d’une planche en bois d’un jeu de l’époque Chimú, planche qui appartient à la collection du Musée Linden en Allemagne. L’auteur apporte des arguments linguistiques et éthnologiques supplémentaires, comme une description des règles du jeu, ce qui appuie l’hypothèse de Nordenskiöld.In the beginning of the 20th century, the Swedish anthropologist Erland Nordenskiöld described a game played by the indigenous people of the Chaco Region at the end of the rainy season (March). Nordenskiöld asserts as a hypothesis that game might have its origins in the Andes. The authors proves that hypothesis correct using an iconografic analysis of a wooden game board of the Chimu culture that is in the collection of the Linden Museum in Germany. The author presents additional linguistic and ethnological arguments as well as a game description that supports Nordenkiöld hypothesis

    A multi-purpose, multi-rotor drone system for long-range and high-altitude volcanic gas plume measurements

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    A multi-rotor drone has been adapted for studies of volcanic gas plumes. This adaptation includes improved capacity for high-altitude and long-range, real-time SO2 concentration monitoring, long-range manual control, remotely activated bag sampling and plume speed measurement capability. The drone is capable of acting as a stable platform for various instrument configurations, including multi-component gas analysis system (MultiGAS) instruments for in situ measurements of SO2, H2S, and CO2 concentrations in the gas plume and portable differential optical absorption spectrometer (MobileDOAS) instruments for spectroscopic measurement of total SO2 emission rate, remotely controlled gas sampling in bags and sampling with gas denuders for posterior analysis on the ground of isotopic composition and halogens. The platform we present was field-tested during three campaigns in Papua New Guinea: in 2016 at Tavurvur, Bagana and Ulawun volcanoes, in 2018 at Tavurvur and Langila volcanoes and in 2019 at Tavurvur and Manam volcanoes, as well as in Mt. Etna in Italy in 2017. This paper describes the drone platform and the multiple payloads, the various measurement strategies and an algorithm to correct for different response times of MultiGAS sensors. Specifically, we emphasize the need for an adaptive flight path, together with live data transmission of a plume tracer (such as SO2 concentration) to the ground station, to ensure optimal plume interception when operating beyond the visual line of sight. We present results from a comprehensive plume characterization obtained during a field deployment at Manam volcano in May 2019. The Papua New Guinea region, and particularly Manam volcano, has not been extensively studied for volcanic gases due to its remote location, inaccessible summit region and high level of volcanic activity. We demonstrate that the combination of a multi-rotor drone with modular payloads is a versatile solution to obtain the flux and composition of volcanic plumes, even for the case of a highly active volcano with a high-altitude plume such as Manam. Drone-based measurements offer a valuable solution to volcano research and monitoring applications and provide an alternativespan idCombining double low line"page4256"/> and complementary method to ground-based and direct sampling of volcanic gases

    One-pot synthesis of hierarchical porous layered hybrid materials based on aluminosilicate sheets and organic functional pillars

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    Layered hybrid materials (LHMs) based on ordered silicoaluminate sheets linked with organic fragments, perpendicularly located and stabilized in the interlayer space, were synthesized by a one-pot direct hydrothermal process in the absence of structural directing agents (SDAs) and using bridged silsesquioxanes as organosilicon precursors. By following the synthesis described here, the preliminary preparation of inorganic layered precursors, post-synthesis swelling and/or pillaring treatments can be avoided. The physico-chemical and structural characteristics of the materials were studied by chemical and thermogravimetrical analyses, X-ray diffraction, TEM microscopy, spectroscopic techniques (NMR and FTIR) and textural measurements. The complete exchange of intracrystalline sodium cations by protons, without substantial structural alteration of the hybrid materials, facilitated the generation of hybrid materials, which contained acid and base sites located in the inorganic (silicoaluminate layers) and in the organic interlayer linkers, respectively, with the resultant acid base materials showing promise as active and selective catalysts.The authors thank financial support to Spanish Government by Consolider-Ingenio MULTICAT CSD2009-00050, MAT2011-29020-C02-01 and Severo Ochoa Excellence Program SEV-2012-0267. AG and JMM thank pre-doctoral fellowships from MINECO for economical support.Gaona Cordero, A.; Moreno, JM.; Velty, A.; Díaz Morales, UM.; Corma Canós, A. (2014). One-pot synthesis of hierarchical porous layered hybrid materials based on aluminosilicate sheets and organic functional pillars. 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    The impacts of risk and competition on bank profitability in China

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    Several rounds of banking reforms in China have aimed to increase the competitive condition and further enhance stability in the Chinese banking sector, while the joint effects of competition and risk-taking behaviour on the profitability in the banking sector have not been studied well enough so far in the literature. The current study contributes to the empirical literature by testing the impacts of risk and competition on profitability in the Chinese banking industry (state-owned, joint-stock and city commercial banks) over the period 2003-2011 under a one-step Generalized Method of Moments (GMM) system estimator. The results do not show any robust finding with regards to the impacts of competition and risk on bank profitability, while it is found that Chinese bank profitability is affected by taxation, overhead cost, labour productivity and inflation. The study provides policy implications to the Chinese banking industry and different ownership types of Chinese commercial banks

    The summertime Boreal forest field measurement intensive (HUMPPA-COPEC-2010): an overview of meteorological and chemical influences

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    This paper describes the background, instrumentation, goals, and the regional influences on the HUMPPA-COPEC intensive field measurement campaign, conducted at the Boreal forest research station SMEAR II (Station for Measuring Ecosystem-Atmosphere Relation) in Hyytiälä, Finland from 12 July–12 August 2010. The prevailing meteorological conditions during the campaign are examined and contrasted with those of the past six years. Back trajectory analyses show that meteorological conditions at the site in 2010 were characterized by a higher proportion of southerly flow than in the other years studied. As a result the summer of 2010 was anomalously warm and high in ozone making the campaign relevant for the analysis of possible future climates. A comprehensive land use analysis, provided on both 5 and 50 km scales, shows that the main vegetation types surrounding the site on both the regional and local scales are: coniferous forest (Scots pine and/or Norway spruce); mixed forest (Birch and conifers); and woodland scrub (e.g. Willows, Aspen); indicating that the campaign results can be taken as representative of the Boreal forest ecosystem. In addition to the influence of biogenic emissions, the measurement site was occasionally impacted by sources other than vegetation. Specific tracers have been used here to identify the time periods when such sources have impacted the site namely: biomass burning (acetonitrile and CO), urban anthropogenic pollution (pentane and SO<sub>2</sub>) and the nearby Korkeakoski sawmill (enantiomeric ratio of chiral monoterpenes). None of these sources dominated the study period, allowing the Boreal forest summertime emissions to be assessed and contrasted with various other source signatures

    Dung removal increases under higher dung beetle functional diversity regardless of grazing intensification

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    Dung removal by macrofauna such as dung beetles is an important process for nutrient cycling in pasturelands. Intensification of farming practices generally reduces species and functional diversity of terrestrial invertebrates, which may negatively affect ecosystem services. Here, we investigate the effects of cattle-grazing intensification on dung removal by dung beetles in field experiments replicated in 38 pastures around the world. Within each study site, we measured dung removal in pastures managed with low- and high-intensity regimes to assess between-regime differences in dung beetle diversity and dung removal, whilst also considering climate and regional variations. The impacts of intensification were heterogeneous, either diminishing or increasing dung beetle species richness, functional diversity, and dung removal rates. The effects of beetle diversity on dung removal were more variable across sites than within sites. Dung removal increased with species richness across sites, while functional diversity consistently enhanced dung removal within sites, independently of cattle grazing intensity or climate. Our findings indicate that, despite intensified cattle stocking rates, ecosystem services related to decomposition and nutrient cycling can be maintained when a functionally diverse dung beetle community inhabits the human-modified landscape

    Salivary Markers for Oral Cancer Detection

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    Oral cancer refers to all malignancies that arise in the oral cavity, lips and pharynx, with 90% of all oral cancers being oral squamous cell carcinoma. Despite the recent treatment advances, oral cancer is reported as having one of the highest mortality ratios amongst other malignancies and this can much be attributed to the late diagnosis of the disease. Saliva has long been tested as a valuable tool for drug monitoring and the diagnosis systemic diseases among which oral cancer. The new emerging technologies in molecular biology have enabled the discovery of new molecular markers (DNA, RNA and protein markers) for oral cancer diagnosis and surveillance which are discussed in the current review

    Potential impacts of offshore oil and gas activities on deep-sea sponges and the habitats they form

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    Sponges form an important component of benthic ecosystems from shallow littoral to hadal depths. In the deep ocean, beyond the continental shelf, sponges can form high-density fields, constituting important habitats supporting rich benthic communities. Yet these habitats remain relatively unexplored. The oil and gas industry has played an important role in advancing our knowledge of deep-sea environments. Since its inception in the 1960s, offshore oil and gas industry has moved into deeper waters. However, the impacts of these activities on deep-sea sponges and other ecosystems are only starting to become the subject of active research. Throughout the development, operation and closure of an oil or gas field many activities take place, ranging from the seismic exploration of subseafloor geological features to the installation of infrastructure at the seabed to the drilling process itself. These routine activities and accidental releases of hydrocarbons during spills can significantly impact the local marine environment. Each phase of a field development or an accidental oil spill will therefore have different impacts on sponges at community, individual and cellular levels. Legacy issues regarding the future decommissioning of infrastructure and the abandonment of wells are also important environmental management considerations. This chapter reviews our understanding of impacts from hydrocarbon exploration and exploitation activities on deep-sea sponges and the habitats they form. These impacts include those (1) at community level, decreasing the diversity and density of benthic communities associated with deep-sea sponges owing to physical disturbance of the seabed; (2) at individual level, interrupting filtration owing to exposure to increased sedimentation; and (3) at cellular level, decreasing cellular membrane stability owing to exposure to drill muds. However, many potential effects not yet tested in deep-sea sponges but observed in shallow-water sponges or other model organisms should also be taken into account. Furthermore, to the best of our knowledge, no studies have shown impact of oil or dispersed oil on deep-sea sponges. To highlight these significant knowledge gaps, a summary table of potential and known impacts of hydrocarbon extraction and production activities combined with a simple “traffic light” scheme is also provided
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