Modernización agropecuaria y pensamiento único, organizaciones corporativas y rol del Estado, oeste y sur de la provincia de Córdoba

El presente trabajo propone reflexionar acerca del papel de la modernización agropecuaria -sustentada en las innovaciones tecnológicas y organizacionales- y las transformaciones en la organización productiva ocurridas en Argentina, desde fines del siglo XIX hasta la actualidad. Por medio de la investigación de la influencia del conocimiento científico en los discursos, representaciones y estrategias de las entidades rurales y del Estado se analiza la influencia de un pensamiento único en la realidad productiva del país. Con este objetivo se realiza primero una contextualización y caracterización global del proceso de modernización agrícola tecno-científica, analizando los conceptos de desarrollo y progreso. Posteriormente se brindan algunos elementos sobre la realidad agrícola argentina y la influencia de diferentes instituciones dentro de este proceso. Por un lado se da cuenta de la presencia de esta racionalidad a través de un recorrido por bibliografía sobre discursos, estrategias y prácticas llevadas a cabo por instituciones tales como la Sociedad Rural Argentina (SRA), la Federación Agraria Argentina (FAA), la Confederación Intercooperativa Agropecuaria (CONINAGRO), Confederaciones Rurales Argentinas (CARBAP) y la Asociación Argentina de Consorcios Regionales de Experimentación Agrícola (AACREA). Por otro lado, se realizará el análisis de entrevistas realizadas a técnicos de entidades agrarias e instituciones estatales vinculados a la producción agropecuaria. Este trabajo brinda una reflexión sobre la presencia hegemónica de un pensamiento único vinculado a la visión de modernidad tecno-científica, progreso, y desarrollo en el agro.Facultad de Humanidades y Ciencias de la Educació

Measurements of droplet size in shear-driven atomization using ultra-small angle x-ray scattering

[EN] Measurements of droplet size in optically-thick, non-evaporating, shear-driven sprays have been made using ultra-small angle x-ray scattering (USAXS). The sprays are produced by orifice-type nozzles coupled to diesel injectors, with measurements conducted from 1 - 24 mm from the orifice, spanning from the optically-dense near-nozzle region to more dilute regions where optical diagnostics are feasible. The influence of nozzle diameter, liquid injection pressure, and ambient density were examined. The USAXS measurements reveal few if any nanoscale droplets, in conflict with a popular computational model of diesel spray breakup. The average droplet diameter rapidly decreases with downstream distance from the nozzle until a plateau value is reached, after which only small changes are seen in droplet diameter. This plateau droplet size is consistent with the droplets being small enough to be stable with respect to further breakup. Liquid injection pressure and nozzle diameter have the biggest impact on droplet size, while ambient density has a smaller effect. (C) 2017 Published by Elsevier Ltd.X-ray spray research at Argonne is supported by the DOE Advanced Combustion Program. We acknowledge team leaders Gurpreet Singh and Leo Breton for their support. These experiments were performed at the 7-BM, 9-ID, and 15-ID beamlines of the Advanced Photon Source, Argonne National Laboratory. ChemMatCARS Sector 15 is principally supported by the Divisions of Chemistry (CHE) and Materials Research (DMR), National Science Foundation, under grant number NSF/CHE-1346572. Use of the Advanced Photon Source, an Office of Science User Facility operated for the U.S. Department of Energy (DOE) Office of Science by Argonne National Laboratory, was supported by the U.S. DOE under Contract No. DE-ACO2-06CH11357. R. Payri was funded by a Fulbright visiting scholar grant in collaboration with the Ministry of Education, Culture and Sports of Spain (reference PRX14/00331) while performing this work. J.P. Viera was funded by the Spanish MINECO grant EEBB-I-15-0976 under project TRA2012-36932.Kastengren, A.; Ilavsky, J.; Viera-Sotillo, JP.; Payri, R.; Duke, DJ.; Swantek, A.; Tilocco, FZ.... (2017). Measurements of droplet size in shear-driven atomization using ultra-small angle x-ray scattering. International Journal of Multiphase Flow. 92:131-139. https://doi.org/10.1016/j.ijmultiphaseflow.2017.03.005S1311399

High spatial resolution imaging of methane and other trace gases with the airborne Hyperspectral Thermal Emission Spectrometer (HyTES)

Currently large uncertainties exist associated with the attribution and quantification of fugitive emissions of criteria pollutants and greenhouse gases such as methane across large regions and key economic sectors. In this study, data from the airborne Hyperspectral Thermal Emission Spectrometer (HyTES) have been used to develop robust and reliable techniques for the detection and wide-area mapping of emission plumes of methane and other atmospheric trace gas species over challenging and diverse environmental conditions with high spatial resolution that permits direct attribution to sources. HyTES is a pushbroom imaging spectrometer with high spectral resolution (256 bands from 7.5 to 12 µm), wide swath (1–2 km), and high spatial resolution (∼ 2 m at 1 km altitude) that incorporates new thermal infrared (TIR) remote sensing technologies. In this study we introduce a hybrid clutter matched filter (CMF) and plume dilation algorithm applied to HyTES observations to efficiently detect and characterize the spatial structures of individual plumes of CH_4, H_2S, NH_3, NO_2, and SO_2 emitters. The sensitivity and field of regard of HyTES allows rapid and frequent airborne surveys of large areas including facilities not readily accessible from the surface. The HyTES CMF algorithm produces plume intensity images of methane and other gases from strong emission sources. The combination of high spatial resolution and multi-species imaging capability provides source attribution in complex environments. The CMF-based detection of strong emission sources over large areas is a fast and powerful tool needed to focus on more computationally intensive retrieval algorithms to quantify emissions with error estimates, and is useful for expediting mitigation efforts and addressing critical science questions

Stratospheric contraction caused by increasing greenhouse gases

Rising emissions of anthropogenic greenhouse gases (GHG) have led to tropospheric warming and stratospheric cooling over recent decades. As a thermodynamic consequence, the troposphere has expanded and the rise of the tropopause, the boundary between the troposphere and stratosphere, has been suggested as one of the most robust fingerprints of anthropogenic climate change. Conversely, at altitudes above ∼55 km (in the mesosphere and thermosphere) observational and modeling evidence indicates a downward shift of the height of pressure levels or decreasing density at fixed altitudes. The layer in between, the stratosphere, has not been studied extensively with respect to changes of its global structure. Here we show that this atmospheric layer has contracted substantially over the last decades, and that the main driver for this are increasing concentrations of GHG. Using data from coupled chemistry-climate models we show that this trend will continue and the mean climatological thickness of the stratosphere will decrease by 1.3 km following representative concentration pathway 6.0 by 2080. We also demonstrate that the stratospheric contraction is not only a response to cooling, as changes in both tropopause and stratopause pressure contribute. Moreover, its short emergence time (less than 15 years) makes it a novel and independent indicator of GHG induced climate change

Polarizability and magnetoplasmonic properties of magnetic general nanoellipsoids

An approach to compute the polarizability tensor of magnetic nanoparticles having general ellipsoidal shape is presented. We find a surprisingly excellent quantitative agreement between calculated and experimental magneto-optical spectra measured in the polar Kerr configuration from nickel nanodisks of large size (exceeding 100 nm) with circular and elliptical shape. In spite of its approximations and simplicity, the formalism presented here captures the essential physics of the interplay between magneto-optical activity and the plasmonic resonance of the individual particle. The results highlight the key role of the dynamic depolarization effects to account for the magneto-optical properties of plasmonic nanostructures

MixInYeast: A Multicenter Study on Mixed Yeast Infections

Invasive candidiasis remains one of the most prevalent systemic mycoses, and several studies have documented the presence of mixed yeast (MY) infections. Here, we describe the epidemiology, clinical, and microbiological characteristics of MY infections causing invasive candidiasis in a multicenter prospective study. Thirty-four centers from 14 countries participated. Samples were collected in each center between April to September 2018, and they were sent to a reference center to confirm identification by sequencing methods and to perform antifungal susceptibility testing, according to the European Committee on Antimicrobial Susceptibility Testing (EUCAST). A total of 6895 yeast cultures were identified and MY occurred in 150 cases (2.2%). Europe accounted for the highest number of centers, with an overall MY rate of 4.2% (118 out of 2840 yeast cultures). Of 122 MY cases, the most frequent combinations were Candida albicans/C. glabrata (42, 34.4%), C. albicans/C. parapsilosis (17, 14%), and C. glabrata/C. tropicalis (8, 6.5%). All Candida isolates were susceptible to amphotericin B, 6.4% were fluconazole-resistant, and two isolates (1.6%) were echinocandin-resistant. Accurate identification of the species involved in MY infections is essential to guide treatment decisions

Beyond arctic and alpine: the influence of winter climate on temperate ecosystems

Winter climate is expected to change under future climate scenarios, yet the majority of winter ecology research is focused in cold-climate ecosystems. In many temperate systems, it is unclear how winter climate relates to biotic responses during the growing season. The objective of this study was to examine how winter weather relates to plant and animal communities in a variety of terrestrial ecosystems ranging from warm deserts to alpine tundra. Specifically, we examined the association between winter weather and plant phenology, plant species richness, consumer abundance, and consumer richness in 11 terrestrial ecosystems associated with the U.S. Long-Term Ecological Research (LTER) Network. To varying degrees, winter precipitation and temperature were correlated with all biotic response variables. Bud break was tightly aligned with end of winter temperatures. For half the sites, winter weather was a better predictor of plant species richness than growing season weather. Warmer winters were correlated with lower consumer abundances in both temperate and alpine systems. Our findings suggest winter weather may have a strong influence on biotic activity during the growing season and should be considered in future studies investigating the effects of climate change on both alpine and temperate systems.This is the publisher’s final pdf. The published article is copyrighted by the Ecological Society of America and can be found at: http://esajournals.onlinelibrary.wiley.com/hub/journal/10.1002/%28ISSN%291939-9170/Keywords: ecosystem stability, temperate ecosystem, US LTER Network, global change, critical climate periods, winterKeywords: ecosystem stability, temperate ecosystem, US LTER Network, global change, critical climate periods, winte