918 resultados para Perforadoras de roca


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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Inversión extranjera directa y desarrollo: la experiencia del Mercosur / Daniel Chudnovsky y Andrés López. -- Desarrollo de ventajas competitivas: pymes exportadoras exitosas en Argentina, Chile y Colombia / Dario Milesi, Virginia Moori, Verónica Robert y Gabriel Yoguel. -- Efectos de la capacitación en la competitividad de la industria manufacturer / Ramón Padilla y Miriam Juárez. -- La inserción laboral de los jóvenes: características, tensiones y desafíos / Jürgen Weller. -- La globalización de la atención de la salud: oportunidades para el Caribe / Richard L. Bernal. -- La protección social en el Caribe de habla inglesa / Oliver Paddison. -- Reforzando un pilar fiscal: el impuesto a la renta dual a la uruguaya / Alberto Barreix y Jerónimo Roca. -- Migraciones internacionales y desarrollo: el impacto socioeconómico de las remesas en Colombia / David Khoudour-Castéras. -- Agentes extrasectoriales y transformaciones recientes en el agro argentine / Clara Craviotti. -- Jueces de la Revista de la CEPAL 2005-2006. -- Orientaciones para los colaboradores de la Revista de la CEPAL. -- La Revista de la CEPAL en Internet . -- Publicaciones recientes de la CEPAL.

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Foreign direct investment and development: the MERCOSUR experience / Daniel Chudnovsky and Andrés López. -- Developing competitive advantages: successful export SMES in Argentina, Chile and Colombia / Dario Milesi, Virginia Moori, Verónica Robert and Gabriel Yoguel. -- Effects of training on competitiveness in the manufacturing sector / Ramón Padilla and Miriam Juárez. -- Youth employment: characteristics, tensions and challenges / Jürgen Weller. -- The globalization of the health-care industry: opportunities for the Caribbean / Richard L. Bernal. -- Social protection in the English-speaking Caribbean / Oliver Paddison. -- Strengthening a fiscal pillar: the Uruguayan dual income tax / Alberto Barreix and Jerónimo Roca. -- International migration and development: the socioeconomic impact of remittances in Colombia / David Khoudour-Castéras. -- Non-sectoral agents and recent changes in Argentina’s agricultural sector / Clara Craviotti. -- Referees for CEPAL Review 2005-2006. -- Guidelines for contributors to the CEPAL Review. -- CEPAL Review on the Internet. -- Recent ECLAC publications.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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This work evaluated the beef quality parameters of 108 bulls randomly administered to three treatments during rearing in pastures and two treatments during fatting in feedlots, including mineral and rumen-protected lipids. Meat and fat color, cooking yield, shear force, sensorial traits and chemical and fatty acid compositions were evaluated. Generally, the beef quality parameters were not affected by the rumen protected lipids; however, supplementation with rumen-protected lipids during the rearing period yielded darker beef and brighter fat and increased beef tenderness in meat aged for 28 days compared to the meat from animals that received only mineral supplementation. In addition, the percent of meat polyunsaturated fatty acids was negatively affected by the inclusion of protected lipids, yielding 5.58 and 3.72% in animals fed with and without rumen-protected lipids, respectively, during the fatting period. (C) 2014 Elsevier Ltd. All rights reserved.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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The enrichment of an organic compound with biofertilizers of microorganisms (solubilizing phosphorus bacteria, BSF) can improve the properties of phosphate fertilizers applied to soils to increase nutrient availability. The experimental design was randomized complete blocks with a factorial 4x2 +1 arrangement of treatments: 1) four sources of phosphorus: phosphate rock, natural phosphate, triple superphosphate (TSP) and Cuban phosphate rock; 2) two sources of bio-fertilizer prepared from filter cake (cane waste) enriched with microorganisms and no enrichment; 3) and an absolute control (no filter cake or fertilizer); repeated three times. Data was analyzed with ANOVA and treatment means were compared using Tukey (p <= 0.05). Assessments of available P (Bray-2 and Oniani methodology) and the quantification of total and solubilizing bacteria and fungi in the soil were performed 30, 60 and 90 d after starting the experiment. After 60 d, the population of BSF was lower in the control (p <= 0.05) and the content of P (Bray-2) was higher for SFT (p <= 0.01). The application of the bio-fertilizer increased the P content compared to the control. At 90 d P (Bray-2) increased with the SFT treatment, which also increased (p P in the soil at 60 and 90 d regardless of the presence of microorganism-enriched bio-fertilizer. The use of filter cake enriched with microorganisms associated with different sources of P, and applied to the soil with a high content of P, did not change the soil populations of total and solubilizing bacteria and fungi in the short term. TSP promoted the highest levels of P in the soil, irrespective of the presence of the organic compound enriched with P solubilizing microorganisms.

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Observations of cosmic rays arrival directions made with the Pierre Auger Observatory have previously provided evidence of anisotropy at the 99% CL using the correlation of ultra high energy cosmic rays (UHECRs) with objects drawn from the Veron-Cetty Veron catalog. In this paper we report on the use of three catalog independent methods to search for anisotropy. The 2pt-L, 2pt+ and 3pt methods, each giving a different measure of self-clustering in arrival directions, were tested on mock cosmic ray data sets to study the impacts of sample size and magnetic smearing on their results, accounting for both angular and energy resolutions. If the sources of UHECRs follow the same large scale structure as ordinary galaxies in the local Universe and if UHECRs are deflected no more than a few degrees, a study of mock maps suggests that these three method can efficiently respond to the resulting anisotropy with a P-value = 1.0% or smaller with data sets as few as 100 events. using data taken from January 1, 2004 to July 31, 2010 we examined the 20, 30, ... , 110 highest energy events with a corresponding minimum energy threshold of about 49.3 EeV. The minimum P-values found were 13.5% using the 2pt-L method, 1.0% using the 2pt+ method and 1.1% using the 3pt method for the highest 100 energy events. In view of the multiple (correlated) scans performed on the data set, these catalog-independent methods do not yield strong evidence of anisotropy in the highest energy cosmic rays.

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Atmospheric conditions at the site of a cosmic ray observatory must be known for reconstructing observed extensive air showers. The Global Data Assimilation System (GDAS) is a global atmospheric model predicated on meteorological measurements and numerical weather predictions. GDAS provides altitude-dependent profiles of the main state variables of the atmosphere like temperature, pressure, and humidity. The original data and their application to the air shower reconstruction of the Pierre Auger Observatory are described. By comparisons with radiosonde and weather station measurements obtained on-site in Malargue and averaged monthly models, the utility of the GDAS data is shown. (C) 2012 Elsevier B.V. All rights reserved.

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The Pierre Auger Observatory is exploring the potential of the radio detection technique to study extensive air showers induced by ultra-high energy cosmic rays. The Auger Engineering Radio Array (AERA) addresses both technological and scientific aspects of the radio technique. A first phase of AERA has been operating since September 2010 with detector stations observing radio signals at frequencies between 30 and 80 MHz. In this paper we present comparative studies to identify and optimize the antenna design for the final configuration of AERA consisting of 160 individual radio detector stations. The transient nature of the air shower signal requires a detailed description of the antenna sensor. As the ultra-wideband reception of pulses is not widely discussed in antenna literature, we review the relevant antenna characteristics and enhance theoretical considerations towards the impulse response of antennas including polarization effects and multiple signal reflections. On the basis of the vector effective length we study the transient response characteristics of three candidate antennas in the time domain. Observing the variation of the continuous galactic background intensity we rank the antennas with respect to the noise level added to the galactic signal.

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The Pierre Auger Observatory is a facility built to detect air showers produced by cosmic rays above 10(17) eV. During clear nights with a low illuminated moon fraction, the UV fluorescence light produced by air showers is recorded by optical telescopes at the Observatory. To correct the observations for variations in atmospheric conditions, atmospheric monitoring is performed at regular intervals ranging from several minutes (for cloud identification) to several hours (for aerosol conditions) to several days (for vertical profiles of temperature, pressure, and humidity). In 2009, the monitoring program was upgraded to allow for additional targeted measurements of atmospheric conditions shortly after the detection of air showers of special interest, e. g., showers produced by very high-energy cosmic rays or showers with atypical longitudinal profiles. The former events are of particular importance for the determination of the energy scale of the Observatory, and the latter are characteristic of unusual air shower physics or exotic primary particle types. The purpose of targeted (or "rapid") monitoring is to improve the resolution of the atmospheric measurements for such events. In this paper, we report on the implementation of the rapid monitoring program and its current status. The rapid monitoring data have been analyzed and applied to the reconstruction of air showers of high interest, and indicate that the air fluorescence measurements affected by clouds and aerosols are effectively corrected using measurements from the regular atmospheric monitoring program. We find that the rapid monitoring program has potential for supporting dedicated physics analyses beyond the standard event reconstruction.

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The surface detector array of the Pierre Auger Observatory can detect neutrinos with energy E-nu between 10(17) eV and 10(20) eV from point-like sources across the sky south of +55 degrees and north of -65 degrees declinations. A search has been performed for highly inclined extensive air showers produced by the interaction of neutrinos of all flavors in the atmosphere (downward-going neutrinos), and by the decay of tau leptons originating from tau neutrino interactions in Earth's crust (Earth-skimming neutrinos). No candidate neutrinos have been found in data up to 2010 May 31. This corresponds to an equivalent exposure of similar to 3.5 years of a full surface detector array for the Earth-skimming channel and similar to 2 years for the downward-going channel. An improved upper limit on the diffuse flux of tau neutrinos has been derived. Upper limits on the neutrino flux from point-like sources have been derived as a function of the source declination. Assuming a differential neutrino flux k(PS) . E-nu(-2). from a point-like source, 90% confidence level upper limits for k(PS) at the level of approximate to 5x10(-7) and 2.5x10(-6) GeV cm(-2) s(-1) have been obtained over a broad range of declinations from the searches for Earth-skimming and downward-going neutrinos, respectively.

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A thorough search of the sky exposed at the Pierre Auger Cosmic Ray Observatory reveals no statistically significant excess of events in any small solid angle that would be indicative of a flux of neutral particles from a discrete source. The search covers from -90 degrees to +15 degrees in declination using four different energy ranges above 1 EeV (10(18) eV). The method used in this search is more sensitive to neutrons than to photons. The upper limit on a neutron flux is derived for a dense grid of directions for each of the four energy ranges. These results constrain scenarios for the production of ultrahigh energy cosmic rays in the Galaxy.