bluuebunny/crossref_metadata_2025_split huggingface dataset:
Red neuronal artificial backpropagation versus modelos empíricos para estimación de radiación global diaria en Sinaloa, México*
Authors: Cervantes-Osornio Rocio , Arteaga Ramírez Ramón , Vázquez Peña Mario A. , Ojeda Bustamante Waldo 
Published: January 2018

Se compararon los resultados de los promedios de radiación global diaria estimados con el modelo de red neuronal artificial (RNA) bakpropagation contra los obtenidos por los modelos empíricos Hargreaves, Angström-Prescott y los calibrados de estos. Se utilizó un modelo de red neuronal artificial backpropagation con el algoritmo Levenberg Marquardt para el pronóstico de los promedios diarios de radiación global de cuatro estaciones ubicadas en el distrito de riego 075 Valle del Fuerte, Los Mochis Sinaloa, México. La base de datos representa promedios diarios con vectores de 1 484 datos para entrenamiento, validación y prueba y 229 para pronóstico. Entre las variables de entrada proporcionadas por el Distrito de riego, fueron: temperatura mínima y temperatura máxima, otras fueron calculadas como: duración real de la insolación, fotoperiodo y radiación solar extraterrestre. Se obtuvieron escenarios con una, dos y tres capas ocultas, con diversos números de neuronas en cada capa oculta. La RNA e6{27} con las entradas temperatura mínima, máxima, horas brillo sol dividida por el fotoperiodo y radiación solar extraterrestre, obtuvo el mejor ajuste, con un RMSE de 1.6871 y R2 de 0.89 para los 1484 datos y para los 229, lo obtuvo el modelo Angström-Prescott calibrado con un RMSE de 2.2812 y R2 de 0.89. Para los 1 484 datos promedios, el escenario e6{27} presenta la mejor estimación de la radiación global diaria (Rs ) y es mejor que los modelos empíricos, sin embargo para los 229 datos el modelo Angström-Prescott calibrado presenta una estimación de Rs mejor al e6{27} de la RNA.
Comportamiento defensivo, sanitario y producción de ecotipos de Apis mellifera L. en Tabasco, México
Authors: Contreras-Ramírez Dulce Nayeli , Pérez León María Isabel , Payró-de la Cruz Emeterio , Rodríguez-Ortiz Gerardo , Castañeda-Hidalgo Ernesto , Gómez-Ugalde Rosa María 
Published: January 2018

La africanización, las enfermedades, especialmente varroasis, la inestabilidad del mercado internacional de la miel y el deterioro del entorno ecológico, ha llevado a una constante investigación sobre como obtener abejas con características de alto rendimiento, baja defensividad y resistencia a enfermedades. El objetivo fue evaluar el comportamiento defensivo, sanitario y productivo de Apis mellifera L. y dos ecotipos de abejas (carniolas y africanizadas) en Centla, Huimanguillo y Tacotalpa, Tabasco, México; durante marzo a mayo de 2014. El clima es húmedo con temperatura media de 27 °C y precipitación media de 2 550 mm anuales. En comportamiento defensivo y sanitario se evaluó mediante la técnica de Payró et al (2010) y la infestación de varroa en adultas mediante la prueba de David de Jong; y se evaluó la producción de miel en peso. Se utilizó un DCA, con 10 colmenas por municipio y se aplicaron las pruebas de Tukey (p= 0.05) y “t”- de Student para separar medias poblacionales. En Tacotalpa, la defensividad (1.7) e infestación de varroa en abeja adulta fue mayor (6.6%). Varroa en cría fue muy ligera en Huimanguillo (0.7%) mientras que en Centla y Tacotalpa se presentaron niveles ligeros. El acicalamiento fue medio en Tacotalpa (39.8%) y ligero en Centla y Huimanguillo. La producción de miel en Huimanguillo fue mayor (58.44 kg colmena). Las abejas carniolas son menos defensivas (4.4). Se concluye que en los tres municipios presentaron colonias higiénicas con remoción mayor a 86%. En abejas carniolas y africanizadas la incidencia de varroa en adultas y en cría, el comportamiento higiénico y la producción de miel son similares.
Plan de Capacitación en el Procesamiento Artesanal del Cambur como Actividad Productiva
Authors: Valencia Navas Gladys Esther 
Published: January 2018

El propósito del presente artículo está centrado en la aplicación de un plan de capacitación en el procesamiento artesanal de la materia prima del cambur como actividad productiva dirigido a los agricultores de la comunidad El Cobalongo, Parroquia Altamira de Cáceres Municipio Bolívar, Estado Barinas. En tal sentido, la investigación está orientada bajo la modalidad de proyecto factible y se desarrollará en las siguientes fases: Fase I: del Diagnóstico, Fase II: Elaboración del programa, Fase III: Evaluación de la Viabilidad, Fase IV: Ejecución del programa y Fase V: Evaluación del impacto del programa. El diseño es de campo de tipo descriptivo por lo que el método a emplear es el descriptivo. La muestra estará conformada por dieciocho (18) productores de cambur de la comunidad antes mencionada, a los que se les aplicará una encuesta, como cuestionario de veinte (20) ítems, con cuatro alternativas de respuesta (siempre, casi siempre, algunas veces y nunca). El que se validará a través de juicio de expertos y su confiabilidad se realizará calculando el coeficiente de Alfa de Cronbach. El procesamiento de los datos se realizará como indican los criterios que se han de emplear para la codificación, tabulación y análisis de la información.
La Interdisciplinariedad y la Hermenéutica como Recursos Pedagógicos para la Elaboración de Proyectos de Aprendizaje
Authors: Villamizar Vega Lizbeth Teresa 
Published: January 2018

Los llamados Proyectos de Aprendizaje (P.A.), se consideran una estrategia metodológica concebida en la escuela y para la escuela, que deben elaborarse en un año escolar producto de un trabajo colaborativo entre la comunidad educativa: estudiantes, docentes y directivos, pero donde algunos docentes no tienen idea clara de la vinculación que pueden darle a los contenidos programáticos de las asignaturas que imparten con el proyecto de aprendizaje, asimismo desconocen que la interdisciplinariedad y la hermenéutica son recursos pedagógicos que le permitirán tanto a docentes como alumnos la búsqueda de la respuesta a ¿qué significa su accionar diario?, es aquí donde se reconoce la necesidad de la visión holística de los docentes que administran las distintas unidades curriculares en las escuelas técnicas, donde deben buscar a través de los P.A. que los alumnos demuestren su capacidad de otorgarle a los nuevos conocimientos, funcionabilidad instrumental y utilidad para resolución de problemas presentes y futuros, que puedan crear seres humanos críticos, reflexivos, humanistas, liberadores y ambientalistas, que beneficien a la comunidad donde se encuentran inmersos, donde la solución del problema sea resuelto con la interpretación de los conocimientos transmitidos, así como con las nuevas competencias interdisciplinarias para buscar soluciones reales a problemas reales.
Educación a Distancia. Alternativa para Estudios Universitarios en la Venezuela de Hoy
Authors: Zapata de López María Mercedes 
Published: January 2018

Si partimos del hecho de que la educación es un derecho humano, el Estado tiene la obligación de garantizar el acceso equitativo al sistema educativo en todos sus niveles. En tal sentido, los gobiernos deben ofrecer alternativas para que la población tenga acceso a ella. Esta alternativa puede ser la Educción a Distancia (EaD), modalidad mediada por las TIC como herramienta de aprendizaje del milenio que ofrece bajo costo, masificación y democratización, con una educación pertinente y eficaz. El objetivo del presente ensayo es mostrar las bondades de la EaD y cómo se ha convertido en una alternativa para la formación de profesionales con la misma calidad y excelencia de los egresados en los sistemas convencionales, fundamentado en los aportes sobre EaD de García, Leal, entre otros. Puntualizando las diferencias más sobresalientes entre la modalidad a distancia y la convencional, el rol de asesores y estudiantes, las características de asesores y estudiantes a distancia; y el aporte científico y humanístico de las investigaciones con sistemas a distancia, que demuestran que la EaD reúne y tiene la competencia educativa para formar recurso humano de vanguardia, con las exigencias del milenio.
Formación en Cultura Ciudadana Espacio para la Responsabilidad Social de las Organizaciones Empresariales
Authors: Méndez Jiménez Elita Marina 
Published: January 2018

En Venezuela convivimos en una época sedienta de paz, de compromiso y convivencia social, de igualdad social, a diario escuchamos decir que hay crisis social, crisis de valores. En esta coyuntura, la educación corresponsablemente impartida es el factor central para reflexionar, inculcar, fortalecer y consolidar en los ciudadanos, valores, formación personal, formación ética y otros temas vinculantes, en suma, cultura ciudadana. Es propósito de este ensayo generar reflexiones en torno a la cultura ciudadana, para ello se mencionan algunos roles, que como acciones gerenciales de corresponsabilidad social, pueden realizar las organizaciones empresariales privadas, para fortalecer el accionar social del individuo en aras de promover los estímulos necesarios para que alcance la condición de buen ciudadano, para quien la idea de vivir en una comunidad próspera y participativa, sea representada en un espacio donde la educación, el buen trato, la igualdad en oportunidades y el respeto a sus semejantes, al hábitat y a la vida en cualquiera de sus expresiones sean la norma.
Surgical Site Infection In Laparotomy
Authors: Bhatta Pashupati N. , Yadav Umesh Kumar , Mishra Gorakh Nath , Jha Randhir , Shrestha Kumar 
Published: January 2018

INTRODUCTION: Surgical site infection (ssi) is one of the most common surgical complications which increases the rate of morbidity and mortality and increases the health care cost by prolonging the hospital stay. AIMS AND OBJECTIVES: The main objective of the study was to find out the incidence of ssi in emergency laparotomy in general surgery and to find out the associated risk factor for ssi.MATERIAL & METHODS: Study was carried out in national medical college, Birgunj from January 2011 to June 2012 after getting ethical clearance from Institutional Review Committee National Medical College. Total 200 cases were included in study and follow up done up to 30 days postoperatively. RESULTS: Out of 200 patients, 76 patients developed ssi. The total incidence of ssi was 38%.The rate ssi in clean-contaminated, contaminated and dirty wound were 18.2%, 33.3% & 45.5% respectively. Age, type of surgical operation and prolonged duration of surgery were the significant risk factor for ssi while sex, BMI were not statistically significant. The median length of hospital stay with ssi was 16 days while the median length of hospital stay without ssi was 10 days.CONCLUSION: The rate of ssi was found to be higher in our study in comparison to western study but neariy same when comparing to study of Asian countries. so, we emphasize for the need of evidence based infection control and recommend for better surveillance program me for control of ssi in each hospital.Journal of Universal College of Medical Sciences (2016) Vol.04 No.01 Issue 13, Page: 22-25
Luminous Efficiency Estimates of Meteors. II. Application to Canadian Automated Meteor Observatory Meteor Events
Authors: Subasinghe Dilini , Campbell-Brown Margaret 
Published: January 2018

Abstract
Luminous efficiency is a necessary parameter for determining meteoroid mass from optical emission. Despite this importance, it is very poorly known, with previous results varying by up to two orders of magnitude for a given speed. We present the most recent study of luminous efficiency values determined with modern high-resolution instruments, by directly comparing dynamic and photometric meteoroid masses. Fifteen non-fragmenting meteoroids were used, with a further five clearly fragmenting events for comparison. Twelve of the fifteen non-fragmenting meteoroids had luminous efficiencies less than 1%, while the fragmenting meteoroids had upper limits of a few tens of per cent. No clear trend with speed was seen, but there was a weak negative trend of luminous efficiency on meteoroid mass, implying that smaller meteoroids radiate more efficiently.
Discovery of a Possible Early-T Thick-disk Subdwarf from the AllWISE2 Motion Survey*
Authors: Kellogg Kendra , Kirkpatrick J. Davy , Metchev Stanimir , Gagné Jonathan , Faherty Jacqueline K. 
Published: January 2018

Abstract
We have discovered a potential T0 ± 1 subdwarf from a search for sources in the AllWISE2 Motion Survey that do not have counterparts in surveys at shorter wavelengths. With a tangential velocity of ∼170 km s−1, this object—WISE J071121.36–573634.2—has kinematics that are consistent with the thick-disk population of the Milky Way. Spectral fits suggest a low-metallicity for this object but also allow for the possibility of unresolved multiplicity. If WISE J0711–5736 is indeed an sdT0 dwarf, it would be only the second early-T subdwarf discovered to date.
Evolutionary Models of Red Supergiants: Evidence for A Metallicity-dependent Mixing Length and Implications for Type IIP Supernova Progenitors
Authors: Chun Sang-Hyun , Yoon Sung-Chul , Jung Moo-Keon , Kim Dong Uk , Kim Jihoon 
Published: January 2018

Abstract
Recent studies on the temperatures of red supergiants (RSGs) in the local universe provide us with an excellent observational constraint on RSG models. We calibrate the mixing length parameter by comparing model predictions with the empirical RSG temperatures in Small and Large Magellanic Clouds, Milky Way, and M31, which are inferred from the TiO band and the spectral energy distribution (SED). Although our RSG models are computed with the MESA code, our result may be applied to other stellar evolution codes, including the BEC and TWIN codes. We find evidence that the mixing length increases with increasing metallicity for both cases where the TiO and SED temperatures of RSGs are used for the calibration. Together with the recent finding of a similar correlation in low-mass red giants by Tayar et al., this implies that the metallicity dependence of the mixing length is a universal feature in post-main sequence stars of both low and high masses. Our result implies that typical Type IIP supernova (SN IIP) progenitors with initial masses of

have a radius range of

regardless of metallicity. As an auxiliary result of this study, we find that the hydrogen-rich envelope mass of SN IIP progenitors for a given initial mass is predicted to be largely independent of metallicity if the Ledoux criterion with slow semiconvection is adopted, while the Schwarzschild models predict systematically more massive hydrogen-rich envelopes for lower metallicity.
Where Is the Flux Going? The Long-term Photometric Variability of Boyajian’s Star
Authors: Simon Joshua D. , Shappee Benjamin J. , Pojmański G. , Montet Benjamin T. , Kochanek C. S. , van Saders Jennifer , Holoien T. W.-S. , Henden Arne A. 
Published: January 2018

Abstract
We present ∼800 days of photometric monitoring of Boyajian’s Star (KIC 8462852) from the All-Sky Automated Survey for Supernovae (ASAS-SN) and ∼4000 days of monitoring from the All Sky Automated Survey (ASAS). We show that from 2015 to the present the brightness of Boyajian’s Star has steadily decreased at a rate of 6.3 ± 1.4 mmag yr−1, such that the star is now 1.5% fainter than it was in 2015 February. Moreover, the longer time baseline afforded by ASAS suggests that Boyajian’s Star has also undergone two brightening episodes in the past 11 years, rather than only exhibiting a monotonic decline. We analyze a sample of ∼1000 comparison stars of similar brightness located in the same ASAS-SN field and demonstrate that the recent fading is significant at ≳99.4% confidence. The 2015–2017 dimming rate is consistent with that measured with Kepler data for the time period from 2009 to 2013. This long-term variability is difficult to explain with any of the physical models for the star’s behavior proposed to date.
Power-law Statistics of Driven Reconnection in the Magnetically Closed Corona
Authors: Knizhnik K. J. , Uritsky V. M. , Klimchuk J. A. , DeVore C. R. 
Published: January 2018

Abstract
Numerous observations have revealed that power-law distributions are ubiquitous in energetic solar processes. Hard X-rays, soft X-rays, extreme ultraviolet radiation, and radio waves all display power-law frequency distributions. Since magnetic reconnection is the driving mechanism for many energetic solar phenomena, it is likely that reconnection events themselves display such power-law distributions. In this work, we perform numerical simulations of the solar corona driven by simple convective motions at the photospheric level. Using temperature changes, current distributions, and Poynting fluxes as proxies for heating, we demonstrate that energetic events occurring in our simulation display power-law frequency distributions, with slopes in good agreement with observations. We suggest that the braiding-associated reconnection in the corona can be understood in terms of a self-organized criticality model driven by convective rotational motions similar to those observed at the photosphere.
OGLE-2014-BLG-0289: Precise Characterization of a Quintuple-peak Gravitational Microlensing Event
Authors: Udalski A. , Han C. , Bozza V. , Gould A. , Bond I. A. ,   and, Mróz P. , Skowron J. , Wyrzykowski Ł. , Szymański M. K. , Soszyński I. , Ulaczyk K. , Poleski R. , Pietrukowicz P. , Kozłowski S. ,   (The OGLE Collaboration), Abe F. , Barry R. , Bennett D. P. , Bhattacharya A. , Donachie M. , Evans P. , Fukui A. , Hirao Y. , Itow Y. , Kawasaki K. , Koshimoto N. , Li M. C. A. , Ling C. H. , Masuda K. , Matsubara Y. , Miyazaki S. , Munakata H. , Muraki Y. , Nagakane M. , Ohnishi K. , Ranc C. , Rattenbury N. , Saito T. , Sharan A. , Sullivan D. J. , Sumi T. , Suzuki D. , Tristram P. J. , Yamada T. , Yonehara A. ,   (The MOA Collaboration), Street R. A. , Tsapras Y. , Bachelet E. , Bramich D. M. , DÁgo G. , Dominik M. , Jaimes R. Figuera , Horne K. , Hundertmark M. , Kains N. , Menzies J. , Schmidt R. , Snodgrass C. , Steele I. A. , Wambsganss J. ,   (Robonet Collaboration), Pogge R. W. , Jung Y. K. , Shin I.-G. , Yee J. C. , Kim W.-T. ,   (The μFun Collaboration), Beichman C. , Carey S. , Novati S. Calchi , Zhu W. ,   (The Spitzer Team)
Published: January 2018

Abstract
We present the analysis of the binary-microlensing event OGLE-2014-BLG-0289. The event light curve exhibits five very unusual peaks, four of which were produced by caustic crossings and the other by a cusp approach. It is found that the quintuple-peak features of the light curve provide tight constraints on the source trajectory, enabling us to precisely and accurately measure the microlensing parallax

π

E

. Furthermore, the three resolved caustics allow us to measure the angular Einstein radius

θ

E

. From the combination of

π

E

and

θ

E

, the physical lens parameters are uniquely determined. It is found that the lens is a binary composed of two M dwarfs with masses

M

1

=
0.52
±
0.04

M

⊙

and

M

2

=
0.42
±
0.03

M

⊙

separated in projection by

a

⊥

=
6.4
±
0.5

au

. The lens is located in the disk with a distance of

D

L

=
3.3
±
0.3

kpc

. The reason for the absence of a lensing signal in the Spitzer data is that the time of observation corresponds to the flat region of the light curve.
The Galaxy–Halo Connection for
as Revealed by the Spitzer Matching Survey of the UltraVISTA Ultra-deep Stripes
Authors: Cowley William I. , Caputi Karina I. , Deshmukh Smaran , Ashby Matthew L. N. , Fazio Giovanni G. , Le Fèvre Olivier , Fynbo Johan P. U. , Ilbert Olivier , McCracken Henry J. , Milvang-Jensen Bo , Somerville Rachel S. 
Published: January 2018

Abstract
The Spitzer Matching Survey of the UltraVISTA ultra-deep Stripes (SMUVS) provides unparalleled depth at 3.6 and 4.5 μm over ∼0.66 deg2 of the COSMOS field, allowing precise photometric determinations of redshift and stellar mass. From this unique data set we can connect galaxy samples, selected by stellar mass, to their host dark matter halos for

, filling in a large hitherto unexplored region of the parameter space. To interpret the observed galaxy clustering, we use a phenomenological halo model, combined with a novel method to account for uncertainties arising from the use of photometric redshifts. We find that the satellite fraction decreases with increasing redshift and that the clustering amplitude (e.g., comoving correlation length/large-scale bias) displays monotonic trends with redshift and stellar mass. Applying ΛCDM halo mass accretion histories and cumulative abundance arguments for the evolution of stellar mass content, we propose pathways for the coevolution of dark matter and stellar mass assembly. Additionally, we are able to estimate that the halo mass at which the ratio of stellar-to-halo mass is maximized is

at

. This peak halo mass is here inferred for the first time from stellar mass-selected clustering measurements at

, and it implies a mild evolution of this quantity for

, consistent with constraints from abundance-matching techniques.
Possible Imprints of Cold-mode Accretion on the Present-day Properties of Disk Galaxies
Authors: Noguchi Masafumi 
Published: January 2018

Abstract
Recent theoretical studies suggest that a significant part of the primordial gas accretes onto forming galaxies as narrow filaments of cold gas without building a shock and experiencing heating. Using a simple model of disk galaxy evolution that combines the growth of dark matter halos predicted by cosmological simulations with a hypothetical form of cold-mode accretion, we investigate how this cold-accretion mode affects the formation process of disk galaxies. It is found that the shock-heating and cold-accretion models produce compatible results for low-mass galaxies owing to the short cooling timescale in such galaxies. However, cold accretion significantly alters the evolution of disk galaxies more massive than the Milky Way and puts observable fingerprints on their present properties. For a galaxy with a virial mass

, the scale length of the stellar disk is larger by 41% in the cold-accretion model than in the shock-heating model, with the former model reproducing the steep rise in the size–mass relation observed at the high-mass end. Furthermore, the stellar component of massive galaxies becomes significantly redder (0.66 in u − r at

), and the observed color–mass relation in nearby galaxies is qualitatively reproduced. These results suggest that large disk galaxies with red optical colors may be the product of cold-mode accretion. The essential role of cold accretion is to promote disk formation in the intermediate-evolution phase (

) by providing the primordial gas having large angular momentum and to terminate late-epoch accretion, quenching star formation and making massive galaxies red.
Dressing the Coronal Magnetic Extrapolations of Active Regions with a Parameterized Thermal Structure
Authors: Nita Gelu M. , Viall Nicholeen M. , Klimchuk James A. , Loukitcheva Maria A. , Gary Dale E. , Kuznetsov Alexey A. , Fleishman Gregory D. 
Published: January 2018

Abstract
The study of time-dependent solar active region (AR) morphology and its relation to eruptive events requires analysis of imaging data obtained in multiple wavelength domains with differing spatial and time resolution, ideally in combination with 3D physical models. To facilitate this goal, we have undertaken a major enhancement of our IDL-based simulation tool, GX_Simulator, previously developed for modeling microwave and X-ray emission from flaring loops, to allow it to simulate quiescent emission from solar ARs. The framework includes new tools for building the atmospheric model and enhanced routines for calculating emission that include new wavelengths. In this paper, we use our upgraded tool to model and analyze an AR and compare the synthetic emission maps with observations. We conclude that the modeled magneto-thermal structure is a reasonably good approximation of the real one.