Voter models on weighted networks

We study the dynamics of the voter and Moran processes running on top of complex network substrates where each edge has a weight depending on the degree of the nodes it connects. For each elementary dynamical step the first node is chosen at random and the second is selected with probability proportional to the weight of the connecting edge. We present a heterogeneous mean-field approach allowing to identify conservation laws and to calculate exit probabilities along with consensus times. In the specific case when the weight is given by the product of nodes' degree raised to a power theta, we derive a rich phase-diagram, with the consensus time exhibiting various scaling laws depending on theta and on the exponent of the degree distribution gamma. Numerical simulations give very good agreement for small values of |theta|. An additional analytical treatment (heterogeneous pair approximation) improves the agreement with numerics, but the theoretical understanding of the behavior in the limit of large |theta| remains an open challenge.Comment: 21 double-spaced pages, 6 figure

Estrategias de internacionalización en las Mypes en el sector textil en Gamarra – La Victoria 2019

Con el objetivo de exportar de las empresas mypes se da la búsqueda de las estrategias de internacionalización que asegurar que el objetivo se cumplirá con éxito. En el Perú, En el Perú al 31 de diciembre de 2019, registró un incremento de 2 millones 734 mil 619 de empresas y en el distrito de La Victoria – Gamarra hay cerca de 27,280 empresas de confección textil, según la información de la INEI. En base a lo anterior expuesto, la presente investigación tuvo como objetivo exponer la Estrategias de internacionalización en las mypes en el sector textil en Gamarra – La Victoria 2019; para lo cual se utilizaron fuentes de información científica en su desarrollo. La metodología utilizada fue de tipo aplicada con un diseño no experimental – transversal. La población estuvo conformada por 22 mypes trabajadores del área operativa de los almacenes aduaneros ubicados en La Victoria, tomando una muestra de 22 mypes. La técnica utilizada fue la encuesta, teniendo como instrumento el cuestionario que contó con 16 ítems para cada dimensión en escala de Likert. El análisis de datos se realizó a través del software estadístico SPSS 24, donde también se midió su confiabilidad a través del Alfa de Cronbach; asimismo, se utilizó el coeficiente de determinación (R2) para definir la contrastación de hipótesis. En conclusión, los resultados mostraron que las hipótesis se relacionan significativamente, es decir, sí existe relación entre las tres primeras hipótesis especificas desarrolladas en las Estrategias de internacionalización en las mypes en el sector textil en Gamarra – La Victoria 2019

Indicadores bibliométricos de la revista de investigación y postgrado, Ciencia, Tecnología y Salud: una historia desde los números

La difusión y divulgación de los resultados de investigación, vital para el desarrollo científico y tecnológico de un país, se realiza en parte, por medio de publicaciones en revistas científicas. Caracterizar la visibilidad de estas revistas permite medir impacto, distribución y mejorar los procesos editoriales. Se analizan las 36 publicaciones científicas (artículos, artículos de revisión y ensayos) del 2014 al 2017 de la Revista Centroamericana de Investigación y Postgrado Ciencia, Tecnología y Salud, midiendo: número y distribución de autores, procedencia institucional, número de citación, número y distribución geográfica de las visitas. Ciencia, Tecnología y Salud, a pesar de ser una revista joven con cuatro números, ha alcanzado un impacto a nivel nacional e internacional, con nueve citas y más de 10,000 visitas en la página. Aunque cuenta con pocas contribuciones internacionales y la mayor parte de sus autores son de la Universidad de San Carlos de Guatemala, se espera que la tendencia a largo plazo mejoren estos indicadores

Park use, perceived park proximity, and neighborhood characteristics: Evidence from 11 cities in Latin America

This study examines how park use may be associated with perceived park proximity, neighborhood-built environment and perceived social disorder in Latin American cities. The study uses self-reported data from the 2016 CAF survey, including 7,970 urban residents from 11 cities across Latin America. Results show positive graded associations between perceived park proximity and use, holding all others constant. Additional factors that were found to be associated with park use are neighborhood formality and related built-environment characteristics, including paved streets and sidewalks. Park use was mostly unrelated to perceived social disorder, with the exception of indigence, with which it is was positively associated. Stronger associations between park proximity and use were observed among those who reported higher prevalence of indigence or begging in their household block. These findings stress the importance of perceived park proximity in enhancing their use in urban Latin America, and challenge the role of social disorder and crime as a barrier for park use

By myself but not alone:Agency, creativity, and extended musical historicity

In this paper we offer a preliminary framework that highlights the relational nature of solo music-making, and its associated capacity to influence the constellation of habits and experiences one develops through acts of musicking. To do so, we introduce the notion of extended musical historicity and suggest that when novice and expert performers engage in individual musical practices, they often rely on an extended sense of agency which permeates their musical experience and shapes their creative outcomes. To support this view, we report on an exploratory, qualitative study conducted with novice and expert music performers. This was designed to elicit a range of responses, beliefs, experiences and meanings concerning the main categories of agency and creativity. Our data provide rich descriptions of solitary musical practices by both novice and expert performers, and reveal ways in which these experiences involve social contingencies that appear to generate or transform creative musical activity. We argue that recognition of the interactive components of individual musicking may shed new light on the cognition of solo and joint music performance, and should inspire the development of novel conceptual and empirical tools for future research and theory

Crop rotational complexity affects plant-soil nitrogen cycling during water deficit

One of the biggest environmental challenges facing agriculture is how to both supply and retain nitrogen (N), especially as precipitation becomes more variable with climate change. We used a greenhouse experiment to assess how contrasting histories of crop rotational complexity affect plant-soil-microbe interactions that govern N processes, including during water stress. With higher levels of carbon and N cycling hydrolytic enzymes, higher mineral-associated organic matter N concentrations, and an altered microbial community, soils from the most complex rotation enabled 80% more corn N uptake under two moisture regimes, compared to soil from monoculture corn. Higher levels of plant N likely drove the changes in corn leaf gas exchange, particularly increasing intrinsic water use efficiency by 9% in the most complex rotation. The water deficit increased the standing pool of nitrate 44-fold in soils with a history of complex crop rotations, compared to an 11-fold increase in soils from the corn monoculture. The implications of this difference must be considered in a whole cropping systems and field context. Cycling of 15N-labeled fresh clover residue into soil N pools did not depend on the water regime or rotation history, with 2-fold higher recovery in the mineral vs. particulate organic N pool. In contrast, the water deficit reduced recovery of clover 15N in corn shoots by 37%, showing greater impacts of water deficit on plant N uptake compared to organic N cycling in soil. This study provides direct experimental evidence that long-term crop rotational complexity influences microbial N cycling and availability with feedbacks to plant physiology. Collectively, these results could help explain general observations of higher yields in more complex crop rotations, including specifically during dry conditions

The Link Between the Hidden Broad Line Region and the Accretion Rate in Seyfert 2 Galaxies

In the past few years more and more pieces of evidence have been presented for a revision of the widely accepted Unified Model of Active Galactic Nuclei. A model based solely on orientation cannot explain all the observed phenomenology. In the following, we will present evidence that accretion rate is also a key parameter for the presence of Hidden Broad Line Regions in Seyfert 2 galaxies. Our sample consists of 21 sources with polarized Hidden Broad Lines and 18 sources without Hidden Broad Lines. We use stellar velocity dispersions from several studies on the CaII and Mg b triplets in Seyfert 2 galaxies, to estimate the mass of the central black holes via the Mbh-{\sigma}\ast relation. The ratio between the bolometric luminosity, derived from the intrinsic (i.e. unabsorbed) X-ray luminosity, and the Eddington luminosity is a measure of the rate at which matter accretes onto the central supermassive black hole. A separation between Compton-thin HBLR and non-HBLR sources is clear, both in accretion rate (log Lbol/LEdd = -1.9) and in luminosity (log Lbol = 43.90). When, properly luminosity-corrected, Compton-thick sources are included, the separation between HBLR and non-HBLR is less sharp but no HBLR source falls below the Eddington ratio threshold. We speculate that non-HBLR Compton-thick sources with accretion rate higher than the threshold, do possess a BLR, but something, probably related to their heavy absorption, is preventing us from observing it even in polarized light. Our results for Compton-thin sources support theoretical expectations. In a model presented by Nicastro (2000), the presence of broad emission lines is intrinsically connected with disk instabilities occuring in proximity of a transition radius, which is a function of the accretion rate, becoming smaller than the innermost stable orbit for very low accretion rates and therefore luminosities.Comment: 23 pages, 4 figure

Spitzer observations of Abell 1763 - I: infrared and optical photometry

We present a photometric analysis of the galaxy cluster Abell 1763 at visible and infrared wavelengths. Included are fully reduced images in r', J, H, and Ks obtained using the Palomar 200in telescope, as well as the IRAC and MIPS images from Spitzer. The cluster is covered out to approximately 3 virial radii with deep 24um imaging (a 5? depth of 0.2 mJy). This same field of 40' by 40' is covered in all four IRAC bands as well as the longer wavelength MIPS bands (70 and 160um). The r' imaging covers 0.8 deg2 down to 25.5 magnitudes, and overlaps with most of the MIPS field of view. The J, H, Ks images cover the cluster core and roughly half of the filament galaxies, which extend towards the neighboring cluster, Abell 1770. This first, in a series of papers on Abell 1763, discusses the data reduction methods and source extraction techniques used for each dataset. We present catalogs of infrared (IR) sources (with 24 and/or 70um emission) and their corresponding emission in the optical (u', g', r', i', z'), and Near- to Far-IR (J, H, Ks, IRAC, and MIPS 160um). We provide the catalogs and reduced images to the community through the NASA/IPAC Infrared Science Archive (IRSA).Comment: 25 pages, 16 figure