Evaluaci?n de la huella h?drica de los sistemas de producci?n agr?cola y pecuario predominantes en la microcuenca la plata, (Ibagu?, Tolima)

116 p. Recurso Electr?nicoLa microcuenca La Plata tributa sus aguas a la cuenca del r?o Combeima, quien abastece agua para el acueducto de Ibagu? (Tolima). La microcuenca cuenta con un ?rea de 2.498 ha, el 86,66% de su cobertura es bosque natural, 7,5% cultivos, 5,75% pastos y 0,15% zonas improductivas. Las actividades productivas han provocado deforestaci?n, aumento en la erosi?n y han alterado la calidad y disponibilidad del agua. A pesar de estas condiciones, no se han definido indicadores de sostenibilidad para el manejo del recurso h?drico en la zona. Por tanto, este trabajo evalua la Huella H?drica (HH) de los sistemas de producci?n agr?cola predominantes en la microcuenca durante el a?o 2015, con el fin de establecer las relaciones causa-efecto a nivel socio-ambiental e indicadores para el manejo sostenible del recurso h?drico. Se calcularon las HH Azul (HA), Verde (HV) y Gris (HG) de los sistemas de producci?n. Los resultados indicaron que la HH de los sistemas de producci?n agr?cola es de 6.628,64 m3.t-1. El Caf? (Coffea arabica Linneo) es el que genera mayor HV. El sistema de producci?n que mayor HG produce es el de Mora (Rubus glaucus Benth). Adem?s, el an?lisis de sostenibilidad evidenci? que la microcuenca presenta un estado cr?tico o ?hotspot? ambiental por competencia de agua verde. Los resultados e indicadores permitieron crear estrategias de respuesta para mejorar la oferta, demanda y calidad del recurso h?drico, con el ?nimo de contribuir a su uso eficiente. Este trabajo recibi? apoyo econ?mico del proyecto ?EOCYT? de la Universidad del Tolima. Palabras claves: Huella H?drica Azul, Huella H?drica Verde, Huella H?drica Gris.The Plata micro-watershed tributes its waters to the Combeima river basin, which supplies water to the Ibagu? aqueduct (Tolima). The microbasin has an area of 2,498 ha, 86.66% of its coverage is natural forest, 7.5% crops, 5.75% pastures and 0.15% unproductive areas. Productive activities have caused deforestation, increased erosion and have altered the quality and availability of water. Despite these conditions, no sustainability indicators have been defined for the management of water resources in the area. Therefore, this work evaluates the Water Footprint (HH) of the predominant agricultural production systems in the microbasin during 2015, in order to establish cause-effect relationships at the socio-environmental level and indicators for the sustainable management of the resource. water HH Blue (HA), Green (HV) and Gray (HG) of the production systems were calculated. The results indicated that the HH of the agricultural production systems is 6,628.64 m3.t-1. Coffee (Coffea arabica Linneo) is the one that generates the highest HV. The production system that produces the most HG is Mora (Rubus glaucus Benth). In addition, the sustainability analysis showed that the microbasin presents a critical state or environmental "hotspot" due to green water competition. The results and indicators allowed to create response strategies to improve the supply, demand and quality of the water resource, with the aim of contributing to its efficient use. This work received financial support from the "EOCYT" project of the Universidad del Tolima.. Keywords: Blue Water Footprint, Green Water Footprint, Gray Water Footprin

A multi-wavelength view of the central kiloparsec region in the Luminous Infrared Galaxy NGC1614

The Luminous Infrared Galaxy NGC1614 hosts a prominent circumnuclear ring of star formation. However, the nature of the dominant emitting mechanism in its central ~100 pc is still under debate. We present sub-arcsecond angular resolution radio, mid-infrared, Pa-alpha, optical, and X-ray observations of NGC1614, aimed at studying in detail both the circumnuclear ring and the nuclear region. The 8.4 GHz continuum emission traced by the Very Large Array (VLA) and the Gemini/T-ReCS 8.7 micron emission, as well as the Pa-alpha line emission, show remarkable morphological similarities within the star-forming ring, suggesting that the underlying emission mechanisms are tightly related. We used an HST/NICMOS Pa-alpha map of similar resolution to our radio maps to disentangle the thermal free-free and non-thermal synchrotron radio emission, from which we obtained the intrinsic synchrotron power-law for each individual region within the central kpc of NGC1614. The radio ring surrounds a relatively faint, steep-spectrum source at the very center of the galaxy, suggesting that the central source is not powered by an AGN, but rather by a compact (r < 90 pc) starburst. Chandra X-ray data also show that the central kpc region is dominated by starburst activity, without requiring the existence of an AGN. We also used publicly available infrared data to model-fit the spectral energy distribution of both the starburst ring and a putative AGN in NGC1614. In summary, we conclude that there is no need to invoke an AGN to explain the observed bolometric properties of the galaxy.Comment: 13 pages, 7 figures, 5 tables. Accepted for publication in Ap

Employment Expectations and Gross Flows by Type of Work Contract

There is growing interest in understanding firms’ temporary and permanent employment practices and how institutional changes shape them. Using data on Spanish establishments, we examine: (a) how employers adjust temporary and permanent job and worker flows to prior employment expectations, and (b) how the 1994 and 1997 labour reforms promoting permanent employment affected establishments’ employment practices. Generally, establishments’ prior employment expectations are realized through changes in all job and worker flows. However, establishments uniquely rely on temporary hires as a buffer to confront diminishing long-run employment expectations. None of the reforms significantly affected establishments’ net temporary or permanent employment flows.http://deepblue.lib.umich.edu/bitstream/2027.42/40032/3/wp646.pd

Spin dynamics for bosons in an optical lattice

We study the internal dynamics of bosonic atoms in an optical lattice. Within the regime in which the atomic crystal is a Mott insulator with one atom per well, the atoms behave as localized spins which interact according to some spin Hamiltonian. The type of Hamiltonian (Heisenberg, Ising), and the sign of interactions may be tuned by changing the properties of the optical lattice, or applying external magnetic fields. When, on the other hand, the number of atoms per lattice site is unknown, we can still use the bosons to perform general quantum computation

Carbon input threshold for soil carbon budget optimization in eroding vineyards

Previous studies have documented that, relative to conventional tillage (CT), alternative soil management (reduced tillage, mulching, or cover crops) decreases soil erosion and increases soil organic matter (SOM) in vineyards. These previous studies, however, failed to consider the loss of soil organic carbon (SOC) with erosion that could occur with the adoption of agro-environmental measures (AEM) in a semiarid environment. Accordingly, the aims of this study were to determine whether changes in SOC content under AEM management are always positive and to develop a conceptual model for estimating the "SOC threshold". The SOC threshold was defined as that level of SOC in an AEM-managed vineyard above which erosion will result in greater loss of C than occur in a comparable vineyard with CT management. SOC was analyzed at a 100 paired sites (vineyards with AEM management vs. CT). The results showed that in some cases the loss of C was higher with AEM than with CT. Overall, the results indicate that the SOC threshold may be a key parameter in determining the best AEM measures for vineyards that are on slopes and therefore vulnerable to erosion

Systemic Effects Induced by Hyperoxia in a Preclinical Model of Intra-abdominal Sepsis

Supplemental oxygen is a supportive treatment in patients with sepsis to balance tissue oxygen delivery and demand in the tissues. However, hyperoxia may induce some pathological effects. We sought to assess organ damage associated with hyperoxia and its correlation with the production of reactive oxygen species (ROS) in a preclinical model of intra-abdominal sepsis. For this purpose, sepsis was induced in male, Sprague-Dawley rats by cecal ligation and puncture (CLP). We randomly assigned experimental animals to three groups: control (healthy animals), septic (CLP), and sham-septic (surgical intervention without CLP). At 18 h after CLP, septic (n = 39), sham-septic (n = 16), and healthy (n = 24) animals were placed within a sealed Plexiglas cage and randomly distributed into four groups for continuous treatment with 21%, 40%, 60%, or 100% oxygen for 24 h. At the end of the experimental period, we evaluated serum levels of cytokines, organ damage biomarkers, histological examination of brain and lung tissue, and ROS production in each surviving animal. We found that high oxygen concentrations increased IL-6 and biomarkers of organ damage levels in septic animals, although no relevant histopathological lung or brain damage was observed. Healthy rats had an increase in IL-6 and aspartate aminotransferase at high oxygen concentration. IL-6 levels, but not ROS levels, are correlated with markers of organ damage. In our study, the use of high oxygen concentrations in a clinically relevant model of intra-abdominal sepsis was associated with enhanced inflammation and organ damage. These findings were unrelated to ROS release into circulation. Hyperoxia could exacerbate sepsis-induced inflammation, and it could be by itself detrimental. Our study highlights the need of developing safer thresholds for oxygen therapy

Thermal Evolution of Dielectric and Piezoelectric properties of Lead-Free Submicron-Structured (Bi0.5Na0.5)0.94Ba0.06TiO3 Ceramics

The challenge to develop high piezoelectric sensitivity and lead-free compositions ferroelectric ceramics has bring new interest to the study of some classical ferroelectrics as (Bi0.5Na0.5)TiO3 and its solid solutions. The composition near the MPB of the system (1-x) (Bi0.5Na0.5)TiO3-xBaTiO3 with x=0.06 (BNBT6) was found to have interesting properties as lead-free piezoelectric ceramic. Processing of ceramics from nanopowders allows getting fine grained, submicron structured, ceramics that are of interest both for the basic studies of size-effects in ferroelectrics and for their use as high frequency ultrasonic transducers. Submicron-structured BNBT6 ceramics, obtained from nanometric powder synthesized by sol gel auto-combustion at 500?C, by hot-pressing at low temperature (700-800?C) and subsequent recrystallization at higher temperature, still moderate (<1100?C), in order to reduce loss of the volatile elements, have been studied. Elastic and piezoelectric coefficients, as well as electromechanical coupling factors, were determined at the resonances of, thickness poled, thin disks and shear plates. The best room temperature piezoelectric coefficient obtained in these BNBT6 fine-grained (~1&#956;m) ceramics (d33=148 pC.N-1, d31= -37 pC.N-1, d15=158 pC.N-1, kt= 40.4%, kp=26.8% and k15=40.2%) can be compared with those reported for coarse-grained ceramics prepared at higher sintering temperatures. The thermal evolution of the dielectric permittivity, piezoelectric coefficients and coupling factors has been also determined and compared with results reported for BNBT6 coarse grained ceramics, which showed a depolarization temperature of ~105?

Thermal depolarization of lead-free (Bi0.5Na0.5)0.94Ba0.06TiO3 piezoceramics monitored by shear resonance of thickness-poled plates

Submicron-structured (Bi0.5Na0.5)0.94Ba0.06TiO3 ceramics, at the Morphotropic Phase Boundary of the solid solution, were prepared from nanometric powder synthesized by sol gel auto-combustion at 500?C. Samples were obtained by hot-pressing (800?C-2h) and subsequent recrystallization at moderate temperature (1050?C-1h) [1]. Accurate resonance measurements at the uncoupled shear mode of thickness-poled plates and their analysis by Alemany software [2] were carried out to obtain electromechanical coupling factors (k15) and piezoelectric (e15, d15) and elastic (sE55)coefficients. Evolution of these as a function of the temperature was determined to study the depolarization process. Results show that irreversible depoling starts from a temperature higher than 120?C. Shear resonance modes are measurable well above the reported depolarization temperature (100?C). A value of d15=105 pC.N-1 was measured at 160?C. This is most probably due to a difuse phase transition from a field-induced ferroelectric (FE) phase to the low temperature non-polar phase at zero field (LTNPZF) phase. The macroscopic ferro-piezoelectricity observed may arise from the coexistence of the FE phase at the nano-scale in the LTNPZF phas

STUDY OF THE O-18+Ni-64 TWO-NEUTRON TRANSFER REACTION AT 84 MeV BY MAGNEX

A study of the two-neutron transfer reaction of the O-18 + Ni-64 system at 84 MeV incident energy to the ground and first 2(+) excited state of the residual Ni-66 nucleus is presented. The experiment was performed at the INFN-LNS (Italy) by using the large acceptance MAGNEX spectrometer. Theoretical models are used in order to disentangle the competition between long-range and short-range correlations

No confirmed cases of Taenia solium taeniasis in a group of recently arrived Sub-Saharan migrants to Italy

One-hundred and sixty-four migrants from Sub-Saharan Africa to Italy were screened with the Taenia solium specific enzyme-linked immunosorbent assay coproantigen (ELISA CoAg) and four (2.4%) were recorded as positive, but with optical density values near to the cut-off. No ELISA CoAg positive samples were confirmed by parasitological methods. Low positivity could be attributed to false positive result or cross-reaction with other Taenia species. Further studies are needed to assess the role of migration on sporadic autochthonous transmission of T. solium taeniasis/cysticercosis in Europe