bluuebunny/crossref_metadata_2025_split huggingface dataset:
On the friction and adhesion hysteresis between polymer brushes attached to curved surfaces: Rate and solvation effects
Authors: de Beer Sissi , Kenmoé G. Djuidjé , Müser Martin H. 
Published: May 2015

Abstract
Computer simulations of friction between polymer brushes are usually simplified compared to real systems in terms of solvents and geometry. In most simulations, the solvent is only implicit with infinite compressibility and zero inertia. In addition, the model geometries are parallel walls rather than curved or rough as in reality. In this work, we study the effects of these approximations and more generally the relevance of solvation on dissipation in polymer-brush systems by comparing simulations based on different solvation schemes. We find that the rate dependence of the energy loss during the collision of brush-bearing asperities can be different for explicit and implicit solvent. Moreover, the non-Newtonian rate dependences differ noticeably between normal and transverse motion, i.e., between head-on and off-center asperity collisions. Lastly, when the two opposing brushes are made immiscible, the friction is dramatically reduced compared to an undersaturated miscible polymer-brush system, irrespective of the sliding direction.
Further Evidence ofDepdc7Dna Hypomethylation in Depression: a Study in Adult Twins
Authors: Córdova-Palomera A. , Fatjó-Vilas M. , Palma-Gudiel H. , Blasco-Fontecilla H. , Kebir O. , Fañanás L. 
Published: May 2015

AbstractLate and early stressful factors have widely been recognized to play a role in the aetiology of depression. Recent research indicates that such adverse environmental stimuli may alter gene expression in humans via epigenetic modifications. While epigenetic changes such as DNA methylation are likely involved in these processes, it is still unknown what specific genomic loci may be hyper- or hypo-methylated in depression. The association between depressive symptoms during the last 30 days (Brief Symptom Inventory [BSI]) and peripheral-blood DNA methylation levels at genomic loci previously reported as epigenetically altered in saliva and brain of depressive patients was evaluated in a community sample of 34 adult Caucasian MZ twins (17 pairs). Intrapair DNA methylation differences in an intron ofDEPDC7(chr11:33040743) were associated with intrapair differences in current depressive symptoms. Accordingly, a site-specific 10% DNA hypomethylation in a co-twin would correlate with a current depressive symptom score around 3.1 BSI points above the score of his/her less-depressed co-twin. These findings indicate thatDEPDC7hypomethylation in peripheral blood DNA may be associated with recent depressive symptomatology, in line with previous results.
Biogeochemical specifics of sapropel formation in Cisbaikalian undrained lakes (exemplified by Lake Ochki)
Authors: Leonova G.A. , Bobrov V.A. , Krivonogov S.K. , Bogush A.A. , Bychinskii V.A. , Mal’tsev A.E. , Anoshin G.N. 
Published: May 2015

Abstract
The biogeochemistry of organic lacustrine sediments (sapropels) has been poorly studied in Siberia. In this paper we show the specifics of sapropel formation caused by low pH and mineralization of water by the example of Lake Ochki in Cisbaikalia. The main sources of organic matter are zoo- and phytoplankton, which concentrate mostly basic chemical elements and also some alkaline, alkali-earth, and chalcophile elements and move them to the sediment. The calculated enrichment factors (EF) have shown that the lake plankton is strongly enriched with phosphorus and chalcophile elements. The calculations have also revealed a great contribution of the plankton to the elemental composition of sapropel (Mebio, %): P (≈100), Cd (57), Br (45), Hg (40), Se and Na (30), Zn (23), K (21), and Ca (15). Elements are rather uniformly distributed throughout the 3.2 m thick sapropel layer. Lithophile elements (Al, Sc, Ti, Y, Zr, Nb) and LREE are mostly from a terrigenous source. The high contents of mobile elements (Cd, Sb, Sn, Pb, Zn) in the upper part of sapropel are probably due to anthropogenic factors. The high Cu and Zn contents in some sapropel layers are probably related to the inflow of deep-level groundwaters, and the elevated contents of Hg, Cd, and Sb might have been caused by forest fires.
Nonlinear waves and solitons in models of fault block geological media
Authors: Bykov V.G. 
Published: May 2015

AbstractThis is an overview of theoretical research on solitons and other nonlinear waves induced by deformation in fault block (fragmented) geological media, including a brief description of available models with their geophysical and geodynamic applications. The cited models correspond to the classical and perturbed sine-Gordon equations and use the rotation angle and displacement of fault blocks as dynamic variables. The models simulate kinematics and dynamics of traveling deformation fronts (kinks and solitons) generated in faulted rocks. The sine-Gordon equation is presented in its seismological and geomechanic applications for description of earthquake data and modeling of strain waves, faulting patterns, and subduction processes, including slow earthquakes and periodic episodic tremor and slow slip (ETS) effects.
Discriminación y violencia contra los estudiantes de medicina de la Universidad de Caldas
Authors: Moreno-Cubillos Carmen Leonor , Sepúlveda-Gallego Luz Elena 
Published: May 2015

Objetivo: Evidenciar y caracterizar los actos de discriminación y violencia, que suceden entre los estudiantes del programa de medicina de la Universidad de Caldas (Colombia). Materiales y método: Estudio descriptivo y de corte, realizado entre el segundo periodo académico de 2010 y el primero de 2011, con fuente de información primaria y muestra seleccionada aleatoriamente constituida por 88 estudiantes de pregrado.
Resultados: El 86.4% de los estudiantes tienen antecedente de haber sido víctima de alguno de los siguientes eventos estudiados: discriminación por aspecto físico, procedencia, género, estrato socioeconómico, orientación sexual y religión; agresión verbal, física y psicológica; abuso de autoridad; acoso laboral; amenaza o intimidación; sanción o castigo; chantaje; burlas, piropos o gestos obscenos; exclusión y acoso sexual. Los tipos de violencia más frecuentemente reportados fueron abuso de autoridad y agresión psicológica.
Conclusión: Los resultados muestran la existencia de discriminación y violencia contra los estudiantes de medicina, y fundamentan la necesidad de realizar intervenciones desde el punto de vista administrativo y de bienestar universitario.
Factores relacionados con el rendimiento académico en alumnos de fisiopatología
Authors: Sanguinetti José María , López Raquel , Vieta María Eugenia , Berruezo Silvana , Chagra Carolina 
Published: May 2015

Introducción: El rendimiento académico está relacionado con diferentes variables.
Objetivos: Evaluar factores sociales, demográficos y hábitos, así como determinar su relación con el rendimiento académico.
Material y métodos: Trabajo observacional, transversal, correlacional entre abril y noviembre de 2012. Se realizó una encuesta a alumnos de Fisiopatología, de la Universidad Nacional de Salta y se constató en noviembre quienes habían regularizado la asignatura. Variables estudiadas: edad, sexo, provincia de origen, condición laboral, si tiene computadora, frecuencia de uso de correo electrónico, utilización de redes sociales, práctica regular de deportes, actividad en organización no gubernamental (ONG), nivel de satisfacción con la carrera, libros leídos en el último año, aprobación de Anatomía, si cursaba por primera vez, situación económica, tipo de educación secundaria.
Materiales y método: Medidas de resumen y comparativo con Test de Fisher para tablas de contingencia, estudiando la relación de: provincia de origen, actividad laboral, actividad en organizaciones no gubernamentales (ONG), hábitos de lectura, si cursaba por primera vez y final de Anatomía aprobado.
Resultados: Edad promedio 21.5 años, 91% sexo femenino, procedentes de Salta 70%, el 23.9% trabajan, 80.3% tienen PC, el 63.8% acceso a internet y el 86.1% Facebook®. El 14% checa diariamente su correo electrónico. El 36.7% practica deportes regularmente y el 25.5% participa en ONG. El 50.5% está “muy satisfecho” con su carrera, sólo el 43.4% leyó dos o más libros en el último año. El 50.3% aprobó Anatomía, el 55.3% cursaba por primera vez y el 52.1% percibía su situación económica como mala o regular. El 63.82% provenía de escuelas públicas y el 41.48% regularizó la materia. Análisis comparativo: Haber aprobado Anatomía y leer dos o más libros se relacionaron con un mejor rendimiento académico; el resto de las variables estudiadas no mostraron relación.
Conclusiones: Es importante tener en cuenta el perfil del estudiante, sus intereses y hábitos para el desarrollo de estrategias, que mejoren el rendimiento académico.
Personalidad, aprendizaje y rendimiento académico en medicina
Authors: Torres-Acosta Noel David , Rodríguez-Gómez Jaime , Acosta-Vargas Miriam 
Published: May 2015

Introducción: El éxito académico durante la vida estudiantil se ve afectado por muchos factores. La personalidad, de acuerdo las Five Factor Model y los enfoques de aprendizaje (profundo, estratégico y superficial) han mostrado ser condicionantes importantes del rendimiento académico.
Objetivo: Encontrar las correlaciones entre enfoques de aprendizaje-promedio de calificaciones (PC), factores de personalidad-PC, enfoques de aprendizaje-factores de personalidad.Material y métodos: Estudio observacional, analítico, transversal y prospectivo. Población de estudio: 204 estudiantes de medicina en una universidad de Nuevo León. Se utilizaron Big Five Inventory (BFI) para medir la personalidad y Approaches and Study Skills Inventory for Students (ASSIST) para medir los enfoques de aprendizaje. Se utilizó correlación r de Pearson para ver las relaciones entre las variables principales del estudio y análisis discriminante para encontrar las variables que mejor describen el desempeño académico.
Resultados: Los resultados mostraron correlaciones significativas entre PC y enfoque profundo, PC y enfoque superficial y PC-responsabilidad de manera general. Asimismo, hubo correlaciones significativas entre neuroticismo-enfoque superficial y enfoque profundo, y los factores de responsabilidad y apertura a la experiencia. En el análisis discriminante se vio que el enfoque profundo y el factor de responsabilidad son los que mejor diferenciaron a los subgrupos.
Discusión: El presente estudio demuestra una asociación significativa entre el factor de responsabilidad y el enfoque profundo con el rendimiento académico, lo que concuerda con estudios previos.
Conclusión: Se sugiere realizar estudios similares utilizando BFI y ASSIST para acoplarlos más a la realidad mexicana.
Distractores en preguntas de opción múltiple para estudiantes de medicina: ¿cuál es su comportamiento en un examen sumativo de altas consecuencias?
Authors: Jurado-Núñez Alma , Flores-Hernández Fernando , Delgado-Maldonado Laura , Sommer-Cervantes Hermann , Martínez-González Adrián , Sánchez- Mendiola Melchor 
Published: May 2015

Introducción: Los exámenes de opción múltiple son la herramienta más utilizada en la evaluación del conocimiento en estudiantes de medicina. Se ha demostrado que tres opciones para cada ítem son suficientes, sin embargo, muchos exámenes en nuestro medio aún están compuestos por preguntas con cinco opciones. El estudio de los distractores no funcionales (DNF) es necesario para mejorar la calidad de los exámenes. Objetivo: Identificar los DNF y su comportamiento en una evaluación sumativa de altas consecuencias en estudiantes de medicina. Método: Se realizó análisis psicométrico del Examen Profesional Teórico de la Facultad de Medicina de la Universidad Nacional Autónoma de México (UNAM), en la versión de 2008. Se calcularon dificultad, discriminación y correlación punto-biserial de cada ítem y de sus cuatro distractores. Se obtuvo la frecuencia de preguntas con cero a cuatro DNF y se valoraron las diferencias de DNF por ítem y sus características psicométricas. Se contrastó el comportamiento psicométrico del examen completo, con una versión en la que se eliminaron los ítems con cuatro DNF. Resultados: El examen tuvo 420 reactivos de opción múltiple con cinco opciones de respuesta, fue contestado por 882 sustentantes. El instrumento tuvo un alfa de Cronbach de 0.93. De los 1 680 distractores evaluados, sólo 788 (46.9%) fueron funcionales. Más de dos tercios del total de ítems contaron con dos o más DNF. Se encontró un promedio de 2.12 ± 0.99 DNF por ítem, la mayoría de los cuales fueron elegidos por menos de 5% de los sustentantes. A mayor cantidad de DNF, mayor índice de dificultad y menor poder de discriminación de los ítems. Conclusiones: Los ítems con dos distractores funcionales comprenden la mayoría de los reactivos del examen. Dos distractores plausibles representan una alternativa asequible para elaborar los ítems, manteniendo o mejorando la confiabilidad y el perfil psicométrico de este tipo de evaluaciones.
Empirical and theoretical study of atelostomate (Echinoidea, Echinodermata) plate architecture: using graph analysis to reveal structural constraints
Authors: Saucède Thomas , Laffont Rémi , Labruère Catherine , Jebrane Ahmed , François Eric , Eble Gunther J. , David Bruno 
Published: May 2015

AbstractDescribing patterns of connectivity among organs is essential for identifying anatomical homologies among taxa. It is also critical for revealing morphogenetic processes and the associated constraints that control the morphological diversification of clades. This is particularly relevant for studies of organisms with skeletons made of discrete elements such as arthropods, vertebrates, and echinoderms. Nonetheless, relatively few studies devoted to morphological disparity have considered connectivity patterns as a level of morphological organization or developed comparative frameworks with proper tools. Here, we analyze connectivity patterns among apical plates in Atelostomata, the most diversified clade among irregular echinoids. The clade comprises approximately 1600 fossil and Recent species (e.g., 25% of post-Paleozoic species of echinoids) and shows high levels of morphological disparity. Plate connectivity patterns were analyzed using tools and statistics of graph theory. To describe and explore the diversity of connectivity patterns among plates, we symbolized each pattern as a graph in which plates are coded as nodes that are connected pairwise by edges. We then generated a comparative framework as a morphospace of connections, in which the disparity of plate patterns observed in nature was mapped and analyzed. Main results show that apical plate patterns are both highly disparate between and within atelostomate groups and limited in number; overall, they also constitute small, compact, and simple structures compared to possible random patterns. Main traits of the evolution of apical plate patterns reveal the existence of strong morphogenetic constraints that are phylogenetically determined. In contrast, evolutionary radiations within atelostomates were accompanied by a clear increase in disparity, suggesting a release of some constraints at the origin of clades.
ECONOMIC REFORMS IN 1970S COLOMBIA: ASSESSING THE STRATEGIC ROLE OF LÓPEZ MICHELSEN’S GOVERNMENT AND THE COFFEE BOOM
Authors: Rojas Rivera Angela M. 
Published: May 2015

ABSTRACTIn this article I build an analytic narrative to provide an integrated and analytical view of the economic reforms that took place in Colombia during the years 1974-1978. Through the use of basic game theory and historical evidence, I present the core of the strategic interactions between several players: Government is depicted as a committed but poorly endowed agenda setter, Coffee as the dominant player and Industry as the contending but relatively weak player. The analysis shows that the 1976 coffee boom changed the interaction between sectors from an assurance to a prisoner’s dilemma game, and identifies as the post-boom solution the Government–Coffee coalition, which carried out a soft version of the initial reforms.
On the Hilbert functions of sets of points in 1 × 1 × 1
Authors: GUARDO ELENA , VAN TUYL ADAM 
Published: May 2015

AbstractLet HX be the trigraded Hilbert function of a set X of reduced points in $\mathbb{P}$1 × $\mathbb{P}$1 × $\mathbb{P}$1. We show how to extract some geometric information about X from HX. This paper generalises a similar result of Giuffrida, Maggioni and Ragusa about sets of points in $\mathbb{P}$1 × $\mathbb{P}$1.
The effects of the interplay of genetics and early environmental risk on the course of internalizing symptoms from late childhood through adolescence
Authors: Musci Rashelle J. , Masyn Katherine E. , Benke Kelly , Maher Brion , Uhl George , Ialongo Nicholas S. 
Published: May 2015

AbstractInternalizing symptoms during adolescence and beyond is a major public health concern, particularly because severe symptoms can lead to the diagnosis of a number of serious psychiatric conditions. This study utilizes a unique sample with a complex statistical method in order to explore Gene × Environment interactions found in internalizing symptoms during adolescence. Data for this study were drawn from a longitudinal prevention intervention study (n = 798) of Baltimore city school children. Internalizing symptom data were collected using self-report and blood or saliva samples genotyped using Affymetrix 6.0 microarrays. A major depression polygenic score was created for each individual using information from the major depressive disorder Psychiatric Genetics Consortium and used as a predictor in a latent trait–state–occasion model. The major depressive disorder polygenic score was a significant predictor of the stable latent trait variable, which captures time-independent phenotypic variability. In addition, an early childhood stressor of death or divorce was a significant predictor of occasion-specific variables. A Gene × Environment interaction was not a significant predictor of the latent trait or occasion variables. These findings support the importance of genetics on the stable latent trait portion of internalizing symptoms across adolescence.
Effects of High-Dose Vitamin D Supplementation on Metabolic Status and Pregnancy Outcomes in Pregnant Women at Risk for Pre-Eclampsia
Authors: Karamali M. , Beihaghi E. , Mohammadi A. A. , Asemi Z. 
Published: May 2015

AbstractThis study was designed to assess the beneficial effects of high-dose (cholecalciferol) vitamin D supplementation on metabolic profiles and pregnancy outcomes among pregnant women at risk for pre-eclampsia. This randomized double-blind placebo-controlled clinical trial was performed among 60 pregnant women at risk for pre-eclampsia according to abnormal uterine artery Doppler waveform. Subjects were randomly divided into 2 groups to receive 50 000 IU vitamin D supplements (n=30) or receive placebo (n=30) every 2 weeks from 20 to 32 weeks of gestation. Fasting blood samples were taken at baseline study and 12 weeks after the intervention to quantify relevant variables. Newborn’s anthropometric measurements were determined. Pregnant women who received cholecalciferol supplements had significantly increased serum 25-hydroxyvitamin D concentrations (+17.92±2.28 vs. +0.27±3.19 ng/ml, p<0.001) compared with the placebo. The administration of cholecalciferol supplements, compared with the placebo, resulted in significant differences in serum insulin concentrations (+1.08±6.80 vs. +9.57±10.32 μIU/ml, p<0.001), homeostasis model of assessment-insulin resistance (HOMA-IR) (+0.19±1.47 vs. +2.10±2.67, p<0.001), homeostatic model assessment-beta cell function (HOMA-B) (+5.82±29.58 vs. +39.81±38.00, p<0.001) and quantitative insulin sensitivity check index (QUICKI) score (−0.009±0.03 vs. −0.04±0.03, p=0.004). Furthermore, cholecalciferol-supplemented pregnant women had increased HDL-cholesterol concentrations (+2.67 ± 8.83 vs. −3.23±7.76 mg/dl, p=0.008) compared with the placebo. Finally, cholecalciferol supplementation led to a significant rise in plasma total antioxidant capacity (TAC) concentrations (+79.00±136.69 vs. −66.91±176.02 mmol/l, p=0.001) compared with the placebo. Totally, the administration of cholecalciferol supplements among pregnant women at risk for pre-eclampsia for 12 weeks had favorable effects on insulin metabolism parameters, serum HDL-cholesterol, and plasma TAC concentrations.
The Ice-Bucket Challenge: The Legitimacy of the Memetic Mode of Cultural Reproduction Is the Message
Authors: Rossolatos George 
Published: May 2015

AbstractThe multimodal video meme of the ice-bucket challenge raises a “bucketful” of questions for media and cultural studies. This article focuses narrowly on unearthing who speaks in this message and what is ultimately communicated. By unpeeling the multiple layers of message structuration with view to discerning the formal structure of the concerned multimodal message, the analysis proceeds with an exploration of the function of the message in the context of a cultural predicament where networking and connectivity constitute overarching cultural values. The argumentative thrust deploys against the background of the assumption that the ice-bucket challenge constitutes a meme as minimal unit of cultural reproduction that functions on both ontic and ontological levels. The offered analysis aims at demonstrating that the enunciator of this unit is the meme itself that summons hosts or enunciatees to legitimate the prereflective memetic mode of cultural reproduction and propagation as overarching mode of communication.
The Role of Visualizing Failure in Estonian Art, 1987–1999: The “Winners’ Generation”
Authors: Orav Kristin 
Published: May 2015

AbstractThis article explores the conditions, possibilities, and meanings of the concept “winners’ generation” in Estonian art in the 1990s. Some of the artists who were labeled by this name had their triumph in the freedom to express ideas that did not serve the dominant discourse, that is, discourse that captured only the interests of those who became successful during the period of change while shutting down realities not in line with their newly constructed norms and values. The ideological transition from socialist to capitalist ways of life in the course of the dissolution of the Soviet Union in 1991 was an opportunity for these artists to become successful via visualizing failure, thus bringing out, but also questioning, the variations within the “victorious” discourse.