84 research outputs found
Ampliación del rango de distribución de Rhipidomys leucodactylus (Rodentia: Cricetidae): una nueva localidad para el Ecuador
La distribución del género Rhipidomys (Rodentia: Cricetidae) comprende desde bosques húmedos de tierras bajas hasta bosques montanos altos en el neotrópico. En el Ecuador la presencia de Rhipidomys leucodactylus está reportada para las estibaciones nororiental, noroccidental y sur suroccidental de la cordillera de los Andes. El registro de un espécimen macho adulto de R. leucodactylus en un bosque montano a una altura de 2164 metros de elevación se convierte en una ampliación del rango de distribución altitudinal para la especie a manera general, además de ser una nueva localidad de registro en el suroriente del Ecuador
Aportes sobre la dieta y distribución del Ocelote Leopardus pardalis (Linné 1758) en los altos Andes de Ecuador
The Ocelot, Leopardus pardalis is a carnivore with wide distribution in South America. In Ecuador, most of the records come from lowland tropical forests and foothills of the Andes (<900 m at sea level), where this species has a variety of prey, particularly small mammals. However, in the high Andean regions, neither their occurrence nor their diet is known. On November 8, 2016 an adult male of L. pardalis was collected dead in the Usho locality, province of Cañar; the record is located in the high-Andean region in south of Ecuador at 2818 meters to sea level. During the evaluation of the specimen, several digested barbs were found and these were associated with the species of short-tailed porcupine, Coendou rufescens. This record shows that L. pardalis occurs at least seasonally in the high-Andean region of Ecuador; It also shows predation on the high-Andean species in their eating habits.El Ocelote, Leopardus pardalis es un carnívoro con amplia distribución en América del sur. En Ecuador, los registros se concentran en bosques tropicales de tierras bajas y en estribaciones de los Andes (< 900 m de elevación), en donde disponen de una variedad de preseas, particularmente de pequeños mamíferos. Sin embargo, en las regiones alto-Andinas no se conoce sobre su presencia ni tampoco sobre su dieta. El 8 de noviembre de 2016 un macho adulto de L. pardalis que fue colectado muerto en la localidad de Usho, provincia del Cañar; el registro está localizado en la región alto-Andina al sur del Ecuador a 2818 m de elevación. Durante la evaluación del espécimen se encontraron varias púas digeridas y asociadas a la especie de Puerco espín de cola corta, Coendou rufescens. Este registro demuestra que L. pardalis ocurre al menos estacionalmente en la región alto-Andina del Ecuador; además demuestra la predación de especies alto-Andinas dentro de sus hábitos alimenticios
Enhanced Particle Classification in Water Cherenkov Detectors Using Machine Learning: Modeling and Validation with Monte Carlo Simulation Datasets
The Latin American Giant Observatory (LAGO) is a ground-based extended cosmic rays observatory designed to study transient astrophysical events, the role of the atmosphere on the formation of secondary particles, and space-weather-related phenomena. With the use of a network of Water Cherenkov Detectors (WCDs), LAGO measures the secondary particle flux, a consequence of the interaction of astroparticles impinging on the atmosphere of Earth. This flux can be grouped into three distinct basic constituents: electromagnetic, muonic, and hadronic components. When a particle enters a WCD, it generates a measurable signal characterized by unique features correlating to the particle’s type and the detector’s specific response. The resulting charge histograms from these signals provide valuable insights into the flux of primary astroparticles and their key characteristics. However, these data are insufficient to effectively distinguish between the contributions of different secondary particles. In this work, we extend our previous research by using detailed simulations of the expected atmospheric response to the primary flux and the corresponding response of our WCDs to atmospheric radiation. This dataset, which was created through the combination of the outputs of the ARTI and Meiga simulation frameworks, simulated the expected WCD signals produced by the flux of secondary particles during one day at the LAGO site in Bariloche, Argentina, situated at 865 m above sea level. This was achieved by analyzing the real-time magnetospheric and local atmospheric conditions for February and March of 2012, where the resultant atmospheric secondary-particle flux was integrated into a specific Meiga application featuring a comprehensive Geant4 model of the WCD at this LAGO location. The final output was modified for effective integration into our machine-learning pipeline. With an implementation of Ordering Points to Identify the Clustering Structure (OPTICS), a density-based clustering algorithm used to identify patterns in data collected by a single WCD, we have further refined our approach to implement a method that categorizes particle groups using advanced unsupervised machine learning techniques. This allowed for the differentiation among particle types and utilized the detector’s nuanced response to each, thus pinpointing the principal contributors within each group. Our analysis has demonstrated that applying our enhanced methodology can accurately identify the originating particles with a high degree of confidence on a single-pulse basis, highlighting its precision and reliability. These promising results suggest the feasibility of future implementations of machine-leaning-based models throughout LAGO’s distributed detection network and other astroparticle observatories for semi-automated, onboard and real-time data analysis.Fil: Torres Peralta, Ticiano Jorge. Universidad Nacional de Tucumán. Facultad de Ciencias Exactas y Tecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Molina, Maria Graciela. Universidad Nacional de Tucumán. Facultad de Ciencias Exactas y Tecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Asorey, Hernán Gonzalo. Comisión Nacional de Energía Atómica. Centro Atómico Bariloche; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte; ArgentinaFil: Sidelnik, Iván Pedro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte; Argentina. Comisión Nacional de Energía Atómica. Gerencia del Área de Energía Nuclear. Gerencia de Ingeniería Nuclear (CAB). División Neutrones y Reactores; ArgentinaFil: Rubio Montero, Antonio Juan. Centro de Investigaciones Energeticas Medioambientales y Tecnologicas (ciemat);Fil: Dasso, Sergio Ricardo. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Ciencias de la Atmósfera y los Océanos; Argentina. Consejo Nacional de Investigaciónes Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Astronomía y Física del Espacio. - Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Astronomía y Física del Espacio; ArgentinaFil: Mayo Garcia, Rafael. Centro de Investigaciones Energeticas Medioambientales y Tecnologicas (ciemat);Fil: Taboada Nuñez, Alvaro. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Tecnología en Detección y Astropartículas. Comisión Nacional de Energía Atómica. Instituto de Tecnología en Detección y Astropartículas. Universidad Nacional de San Martín. Instituto de Tecnología en Detección y Astropartículas; ArgentinaFil: Otiniano, Luis. No especifíca
Parallel evolutionary biclustering of short-term electric energy consumption
Presentación realizada en el marco del Proyecto PINV18-661: Análisis de la eficiencia energética en edificios no residenciales mediante técnicas metaheurísticas y de inteligencia artificial.CONACYT - Consejo Nacional de Ciencias y TecnologíaPROCIENCI
Fodder, Nitrogen, and Energy Balances in Grasslands with Algarroba Trees (Prosopis juliflora (S.W.) DC.) under Dairy Cow Grazing
The purpose of this study was to evaluate the effect of algarroba (Prosopis juliflora (S.W.) DC.) on fodder, nitrogen and energy contents in Ecuadoran dairy farm grasslands. The study was made at ESPAM bovine facility, 15 meters above sea level, in Manabí, 00º49’23’’, south latitude, and 80º11’01” west longitude, with 962.4 mm of annual precipitation, between September 2011 and December 2014. The stocking rate was 1.09 LU/ha. The areas were populated with 1-4 algarroba trees/ha by 2011, and 8-35 trees/ha, in 2014. Fodder, nitrogen, and energy balances depended on the arborization degree. As a result, 52 t of DM were estimated in 2014, in comparison to the 21 t produced in 2011. Nitrogen was higher with increased arborization between 2011 (60.9 kg/ha), greater nutrient intake from external sources, and 2014 (39.3 kg/ha), with less use of supplements and mineral fertilizers, and greater N2 contribution by arborization. The energy values were higher in 2014, with an increase in algarroba population/ha. The rise in trees/ha in 2014 favored forage yields, with improved N2 and energy efficiency, which was linked to the benefits acquired by the grassland, the contribution of nitrogen to the ecosystem, and the reduction in feed and fertilizer consumption, which led to energy savings
Balance forrajero, de energía y nitrógeno en pastizales arborizados con Algarrobo (Prosopis juliflora (S.W.) DC.) bajo pastoreo de vacas lecheras
El objetivo del estudio fue evaluar el efecto de la arborización de pastizales con Algarrobo (Prosopis juliflora (S.W.) DC. en los balances forrajero, de nitrógeno y energía en fincas ganaderas con vacas lecheras en Ecuador. El trabajo se hizo en el Hato bovino de la ESPAM, situado a 15 msnm en Manabí, a los 00º49’23’’ de Latitud Sur y 80º11’01” de Longitud Oeste y 962,4 mm de lluvia anual, entre septiembre de 2011 y diciembre de 2014. La carga fue de 1,09 UGM/ha. Las áreas tenían arborización de 1-4 árboles de Algarrobo/ha en 2011 y 8-35 árboles/ha en 2014. Se realizaron balances forrajeros, de nitrógeno y energía en función de la arborización. Los balances fueron de 21 t de MS en 2011 frente a 52 t en 2014. Los balances de N2, fueron favorables con el incremento de la arborización entre el año 2011 con 60,9 kg/ha con mayores ingresos del nutriente por insumos extras y 39,3 kg/ha en 2014 con menos ingresos de N2 por balanceados y fertilizantes minerales y dependió más del aporte de N2 por la arborización. El balance de energía fue mejor en 2014 con incremento en las poblaciones/ha de Algarrobo. El incremento de árboles/ha en 2014, favoreció los rendimientos de forrajes del sistema con mejoras en la eficiencia de uso del N2 y la energía, lo que está ligado a beneficios en el pastizal, los aportes de nitrógeno al ecosistema ganadero y reducción de alimentos y fertilizantes que favoreció su economía energética.AbstractThe purpose of this study was to evaluate the effect of Algarroba (Prosopis juliflora (S.W.) DC.) trees on nitrogen-energy forage contents, on Ecuadorian dairy farms grasslands. The study was made at ESPAM bovine facility, 15 meters above sea level, in Manabí, 00º49’23’’, south latitude, and 80º11’01” west longitude, with 962.4 mm annual precipitation, between September 2011 and December 2014. The stocking rate was 1.09 LU/ha. There were 1-4 algarroba trees/ha by 2011, and 8-35 trees/ha, in 2014. Evaluations of forage nitrogen and energy were based on the effects of arborization. As a result, 52 t of DM were estimated in 2014, in comparison to the 21 t of 2011. Nitrogen was higher with increased arborization between 2011 (60.9 kg/ha), with greater nutrient intake from external sources, and 2014 (39.3 kg/ha), with less input of supplements and mineral fertilizers, and greater N2 contribution by arborization. Energy was higher in 2014, with an increase in algarroba population/ha. The increase of trees/ha favored forage yields, with improved N2 and energy efficiency, which was linked to the benefits acquired by the grassland, the contribution of livestock to the ecosystem, and the reduction in feeds and fertilizers
Survival in Southern European patients waitlisted for kidney transplant after graft failure: A competing risk analysis
Background Whether patients waitlisted for a second transplant after failure of a previous kidney graft have higher mortality than transplant-näive waitlisted patients is uncertain. Methods We assessed the relationship between a failed transplant and mortality in 3851 adult KT candidates, listed between 1984–2012, using a competing risk analysis in the total population and in a propensity score-matched cohort. Mortality was also modeled by inverse probability weighting (IPTW) competing risk regression. Results At waitlist entry 225 (5.8%) patients had experienced transplant failure. All-cause mortality was higher in the post-graft failure group (16% vs. 11%; P = 0.033). Most deaths occurred within three years after listing. Cardiovascular disease was the leading cause of death (25.3%), followed by infections (19.3%). Multivariate competing risk regression showed that prior transplant failure was associated with a 1.5-fold increased risk of mortality (95% confidence interval [CI], 1.01–2.2). After propensity score matching (1:5), the competing risk regression model revealed a subhazard ratio (SHR) of 1.6 (95% CI, 1.01–2.5). A similar mortality risk was observed after the IPTW analysis (SHR, 1.7; 95% CI, 1.1–2.6). Conclusions Previous transplant failure is associated with increased mortality among KT candidates after relisting. This information is important in daily clinical practice when assessing relisted patients for a retransplant.This study was supported in part by the Spanish Ministry of Economy and Competitiveness
(MINECO) (grant ICI14/00016) from the Instituto de Salud Carlos III co-funded by the Fondo
Europeo de Desarrollo Regional±FEDER, RETICS (REDINREN RD16/0009/0006, RD16/0009/0031
Measurement of the cosmic ray spectrum above eV using inclined events detected with the Pierre Auger Observatory
A measurement of the cosmic-ray spectrum for energies exceeding
eV is presented, which is based on the analysis of showers
with zenith angles greater than detected with the Pierre Auger
Observatory between 1 January 2004 and 31 December 2013. The measured spectrum
confirms a flux suppression at the highest energies. Above
eV, the "ankle", the flux can be described by a power law with
index followed by
a smooth suppression region. For the energy () at which the
spectral flux has fallen to one-half of its extrapolated value in the absence
of suppression, we find
eV.Comment: Replaced with published version. Added journal reference and DO
Energy Estimation of Cosmic Rays with the Engineering Radio Array of the Pierre Auger Observatory
The Auger Engineering Radio Array (AERA) is part of the Pierre Auger
Observatory and is used to detect the radio emission of cosmic-ray air showers.
These observations are compared to the data of the surface detector stations of
the Observatory, which provide well-calibrated information on the cosmic-ray
energies and arrival directions. The response of the radio stations in the 30
to 80 MHz regime has been thoroughly calibrated to enable the reconstruction of
the incoming electric field. For the latter, the energy deposit per area is
determined from the radio pulses at each observer position and is interpolated
using a two-dimensional function that takes into account signal asymmetries due
to interference between the geomagnetic and charge-excess emission components.
The spatial integral over the signal distribution gives a direct measurement of
the energy transferred from the primary cosmic ray into radio emission in the
AERA frequency range. We measure 15.8 MeV of radiation energy for a 1 EeV air
shower arriving perpendicularly to the geomagnetic field. This radiation energy
-- corrected for geometrical effects -- is used as a cosmic-ray energy
estimator. Performing an absolute energy calibration against the
surface-detector information, we observe that this radio-energy estimator
scales quadratically with the cosmic-ray energy as expected for coherent
emission. We find an energy resolution of the radio reconstruction of 22% for
the data set and 17% for a high-quality subset containing only events with at
least five radio stations with signal.Comment: Replaced with published version. Added journal reference and DO
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