bluuebunny/crossref_metadata_2025_split huggingface dataset:
Fluctuations in 1D stochastic homogenization of pseudo-elliptic equations with long-range dependent potentials
Authors: Lechiheb Atef , Haouala Ezeddine 
Published: February 2018

AbstractThis paper deals with the homogenization problem of one-dimensional pseudo-elliptic equations with a rapidly varying random potential. The main purpose is to characterize the homogenization error (random fluctuations), i.e., the difference between the random solution and the homogenized solution, which strongly depends on the autocovariance property of the underlying random potential. It is well known that when the random potential has short-range dependence, the rescaled homogenization error converges in distribution to a stochastic integral with respect to standard Brownian motion. Here, we are interested in potentials with long-range dependence and we prove convergence to stochastic integrals with respect to the Hermite process.
Full column rank preservers that preserve semipositivity of matrices
Authors: Arumugasamy Chandrashekaran , Jayaraman Sachindranath 
Published: February 2018

Abstract
Left invertibility preservers on Mm,n(ℝ), m ≥ n, that preserve either semipositivity of matrices or the subset of minimally semipositive matrices are studied. We prove that such maps cannot be degenerate. We also highlight the structure of nonsingular subspaces of dimension 2 in M2(ℝ).
Experimental Study in the Modification of Mortar Samples with Incorporated Rice Husk
Authors: Liu Jiesheng , Li Faping , He Xiang , Liu Xiaofan , Zhang Rongtang 
Published: February 2018

Abstract
The aim of this work is to investigate the influence of rice husk (RH) on the properties of mortar. Two different RH were used as integral additives in the mortar samples: direct natural RH addition to the mortar and the use of pretreated RH. The results of such modification are described, taking into consideration the interaction between the RH and mortar. In addition, the physical properties, visual observation and microstructure of mortar prepared with different amount of modified RH were experimentally studied. The test results indicated that modification of RH enhanced the interaction between the RH and mortar because of the impurities removal and rougher surface. Comparing with the natural RH, the modification of RH increases the density and the mechanical properties. The addition of RH can increase the pore number of the mortar mixture, resulting in decrease in the density and mechanical properties of mortar. Morphology characterization results showed that the modification of RH results in an improvement in the interaction between the RH and mortar and further increase in RH content increases the number of pores in the mortar structure.
Overlapping Role of SCYL1 and SCYL3 in Maintaining Motor Neuron Viability
Authors: Kuliyev Emin , Gingras Sebastien , Guy Clifford S. , Howell Sherie , Vogel Peter , Pelletier Stephane 
Published: February 2018

Members of the SCY1-like (SCYL) family of protein kinases are evolutionarily conserved and ubiquitously expressed proteins characterized by an N-terminal pseudokinase domain, centrally located Huntingtin, elongation factor 3, protein phosphatase 2A, yeast kinase TOR1 repeats, and an overall disorganized C-terminal segment. In mammals, three family members encoded by genesScyl1,Scyl2, andScyl3have been described. Studies have pointed to a role for SCYL1 and SCYL2 in regulating neuronal function and viability in mice and humans, but little is known about the biological function of SCYL3. Here, we show that the biochemical and cell biological properties of SCYL3 are similar to those of SCYL1 and both proteins work in conjunction to maintain motor neuron viability. Specifically, although lack ofScyl3in mice has no apparent effect on embryogenesis and postnatal life, it accelerates the onset of the motor neuron disorder caused byScyl1deficiency. Growth abnormalities, motor dysfunction, hindlimb paralysis, muscle wasting, neurogenic atrophy, motor neuron degeneration, and loss of large-caliber axons in peripheral nerves occurred at an earlier age inScyl1/Scyl3double-deficient mice than inScyl1-deficient mice. Disease onset also correlated with the mislocalization of TDP-43 in spinal motor neurons, suggesting that SCYL1 and SCYL3 regulate TDP-43 proteostasis. Together, our results demonstrate an overlapping role for SCYL1 and SCYL3in vivoand highlight the importance the SCYL family of proteins in regulating neuronal function and survival. Only male mice were used in this study.SIGNIFICANCE STATEMENTSCYL1 and SCYL2, members of the SCY1-like family of pseudokinases, have well established roles in neuronal function. Herein, we uncover the role of SCYL3 in maintaining motor neuron viability. Although targeted disruption ofScyl3in mice had little or no effect on embryonic development and postnatal life, it accelerated disease onset associated with the loss ofScyl1, a novel motor neuron disease gene in humans.Scyl1andScyl3double-deficient mice had neuronal defects characteristic of amyotrophic lateral sclerosis, including TDP-43 pathology, at an earlier age than didScyl1-deficient mice. Thus, we show that SCYL1 and SCYL3 play overlapping roles in maintaining motor neuronal viabilityin vivoand confirm that SCYL family members are critical regulators of neuronal function and survival.
Abstract Memory Representations in the Ventromedial Prefrontal Cortex and Hippocampus Support Concept Generalization
Authors: Bowman Caitlin R. , Zeithamova Dagmar 
Published: February 2018

Memory function involves both the ability to remember details of individual experiences and the ability to link information across events to create new knowledge. Prior research has identified the ventromedial prefrontal cortex (VMPFC) and the hippocampus as important for integrating across events in the service of generalization in episodic memory. The degree to which these memory integration mechanisms contribute to other forms of generalization, such as concept learning, is unclear. The present study used a concept-learning task in humans (both sexes) coupled with model-based fMRI to test whether VMPFC and hippocampus contribute to concept generalization, and whether they do so by maintaining specific category exemplars or abstract category representations. Two formal categorization models were fit to individual subject data: a prototype model that posits abstract category representations and an exemplar model that posits category representations based on individual category members. Latent variables from each of these models were entered into neuroimaging analyses to determine whether VMPFC and the hippocampus track prototype or exemplar information during concept generalization. Behavioral model fits indicated that almost three-quarters of the subjects relied on prototype information when making judgments about new category members. Paralleling prototype dominance in behavior, correlates of the prototype model were identified in VMPFC and the anterior hippocampus with no significant exemplar correlates. These results indicate that the VMPFC and portions of the hippocampus play a broad role in memory generalization and that they do so by representing abstract information integrated from multiple events.SIGNIFICANCE STATEMENTWhether people represent concepts as a set of individual category members or by deriving generalized concept representations abstracted across exemplars has been debated. In episodic memory, generalized memory representations have been shown to arise through integration across events supported by the ventromedial prefrontal cortex (VMPFC) and hippocampus. The current study combined formal categorization models with fMRI data analysis to show that the VMPFC and anterior hippocampus represent abstract prototype information during concept generalization, contributing novel evidence of generalized concept representations in the brain. Results indicate that VMPFC–hippocampal memory integration mechanisms contribute to knowledge generalization across multiple cognitive domains, with the degree of abstraction of memory representations varying along the long axis of the hippocampus.
Identification of Two Distinct Classes of the Human INO80 Complex Genome-Wide
Authors: Runge John S , Raab Jesse R , Magnuson Terry 
Published: February 2018

Abstract
Chromatin remodeling and histone modifying enzymes play a critical role in shaping the regulatory output of a cell. Although much is known about these classes of proteins, identifying the mechanisms by which they coordinate gene expression programs remains an exciting topic of investigation. One factor that may contribute to the targeting and activity of chromatin regulators is local chromatin landscape. We leveraged genomic approaches and publically-available datasets to characterize the chromatin landscape at targets of the human INO80 chromatin remodeling complex (INO80-C). Our data revealed two classes of INO80-C targets with distinct chromatin signatures. The predominant INO80-C class was enriched for open chromatin, H3K27ac, and representative subunits from each of the three INO80-C modules (RUVBL1, RUVBL2, MCRS1, YY1). We named this class Canonical INO80. Notably, we identified an unexpected class of INO80-C targets that contained only the INO80 ATPase and harbored a repressive chromatin signature characterized by inaccessible chromatin, H3K27me3, and the methyltransferase EZH2. We named this class Non-Canonical INO80 (NC-INO80). Biochemical approaches indicated that INO80-C and the H3K27 acetyltransferase P300 physically interact, suggesting INO80-C and P300 may jointly coordinate chromatin accessibility at Canonical INO80 sites. No interaction was detected between INO80-C and EZH2, indicating INO80-C and EZH2 may engage in a separate form of regulatory crosstalk at NC-INO80 targets. Our data indicate that INO80-C is more compositionally heterogenous at its genomic targets than anticipated. Moreover, our data suggest there is an important link between INO80-C and histone modifying enzymes that may have consequences in developmental and pathological contexts.
Identification of sibling species in the genus Eucyclops from water-bodies of Ukraine and Russia using crossbreeding studies
Authors: Monchenko V. I. , Gaponova L. P. , Alekseev V. R. 
Published: February 2018

Crossbreeding experiments were used to estimate cryptic species in water bodies of Ukraine and Russia because the most useful criterion in species independence is reproductive isolation. The problem of cryptic species in the genus Eucyclops was examined using interpopulation crosses of populations collected from Baltic Sea basin (pond of Strelka river basin) and Black Sea basin (water-reservoires of Dnieper, Dniester and Danube rivers basins). The results of reciprocal crosses in Eucyclops serrulatus-group are shown that E. serrulatus from different populations but from water bodies belonging to the same river basin crossed each others successfully. The interpopulation crosses of E. serrulatus populations collected from different river basins (Dnipro, Danube and Dniester river basins) were sterile. In this group of experiments we assigned evidence of sterility to four categories: 1) incomplete copulation or absence of copulation; 2) nonviable eggs; 3) absence of egg membranes or egg sacs 4) empty egg membranes. These crossbreeding studies suggest the presence of cryptic species in the E. serrulatus inhabiting ecologically different populations in many parts of its range. The same crossbreeding experiments were carries out between Eucyclops serrulatus and morphological similar species – Eucyclops macruroides from Baltic and Black Sea basins. The reciprocal crossings between these two species were sterile. Thus taxonomic heterogeneity among species of genus Eucyclops lower in E. macruroides than in E. serrulatus. The interpopulation crosses of E. macruroides populations collected from distant part of range were fertile. These crossbreeding studies suggest that E. macruroides species complex was evaluated as more stable than E. serrulatus species complex.
«Biological and bioorganic chemistry». 2 Vol. Vol. 1 «Molecular organization of living matter. Metabolisms and bioenergetics». Vol. 2 «Bіоchemical aspects of molecular biology and intercellular communications» / L. I. Ostapchenko, V. K. Rybalchenko
Authors: Severynovska O. V. , Kyrychenko S. V. 
Published: February 2018

The article reviews the textbook «Biological and Bioorganic Chemistry», intended for students of biological specialties. The textbook examines the main provisions of static and dynamic biochemistry – the science of the pathways and mechanisms of biochemical processes occurring in the cell. Not only the general characteristics of metabolic activity, but also sections related to the regulation of metabolism and the physiological functions of cells are presented. The mechanisms of global metabolic regulation, which are characteristic for all living organisms, are disclosed. The textbook is intended for students of higher educational institutions receiving education in the areas of «Biology», «Ecology», «Chemical technology and biotechnology»; specialties «Biology», «Physiology», «Microbiology», «Biotechnology», «Molecular biology», «Bioecology». It is of interest for specialists, researchers, postgraduates and doctoral students who need basic biochemical preparation.
REIMPERIALIZACIÓN EN EL ORDEN INTERNACIONAL CONTEMPORÁNEO. RUSIA Y SU RECONSTRUCCIÓN HISTÓRICA
Authors: Patiño Villa Carlos Alberto 
Published: February 2018

El final de la Guerra Fría dejó la idea de que Washington quedaba a la cabeza del orden internacional y Rusia dejaba de ser un imperio para ser considerado un Estado-nación, situación que no ha sido aceptada por Moscú. En ese contexto se pretende indagar por el rumbo del orden internacional contemporáneo, creado en 1945 al final de la Segunda Guerra Mundial, y que ha experimentado la más aguda transformación con el proceso de la implosión soviética. Dicha indagación se trabajó con el análisis de fuentes secundarias tales como: investigaciones de expertos, información provista por medios de comunicación de relevancia global y uso de informaciones y datos provenientes de revistas y think tanks especializados. Como conclusiones se destacan: la clara intención de Rusia de evitar acercamientos de la OTAN en sus territorios de interés y la incertidumbre internacional en cuanto al accionar de Washington y su posición geoestratégica respecto a Rusia.
FINANCIAMIENTO PÚBLICO Y SUPERVIVENCIA DE PARTIDOS POLÍTICOS MINORITARIOS EN MÉXICO
Authors: Leyva Cordero Oswaldo , Tamez González Gerardo , Montalvo Herrera Daniela , Ganga Francisco 
Published: February 2018

En el presente artículo se aborda el tema del financiamiento público, el cual es un elemento determinante de los partidos políticos para el cumplimiento de sus funciones sociales y políticas. Este, además, permite la existencia de un sistema plural de partidos, donde los partidos políticos minoritarios son fundamentales para el sistema democrático, a fin de que la totalidad de las voces sean escuchadas y representadas. El objetivo es identificar, a través de técnicas cuantitativas, las diferencias de opinión entre los miembros de partidos políticos mayoritarios y minoritarios, sobre las reglas que rigen el reparto de los recursos públicos, con miras a establecer si las condiciones legales aseguran una efectiva distribución y si el financiamiento público constituye un límite para el desarrollo de los partidos minoritarios.
¿VERDAD O FICCIÓN? EL USO POLÍTICO DE LAS REDES SOCIALES EN LA PARTICIPACIÓN POLÍTICA OFFLINE EN LAS ELECCIONES PRESIDENCIALES EN ECUADOR
Authors: Zumárraga Espinosa Marcos , Reyes Valenzuela Carlos , Carofilis Cedeño Cynthia 
Published: February 2018

El presente artículo explora la relación entre distintos tipos de uso político de las redes sociales y la participación política offline, así como el efecto político-movilizador diferenciado de las plataformas Facebook, Twitter y WhatsApp en un contexto de elecciones presidenciales en Ecuador. Los resultados confirman que: (i) las redes sociales estimulan la movilización de las personas hacia conductas políticas offline; (ii) este efecto movilizador se limita a las plataformas Facebook y WhatsApp y (iii) los usos políticos de tipo expresivo y de contacto con los grupos políticos influyen con mayor fuerza sobre la participación política offline. Se discuten las implicacionesde estos hallazgos en el marco del debate sobre el efecto movilizador de las redes sociales en el grado de activismo político offline.
LA DEFENSA COLECTIVA DE LA DEMOCRACIA EN AMÉRICA LATINA: ¿POR QUÉ?, ¿CÓMO?, ¿CUÁNDO?
Authors: González Manuel Camilo , Liendo Nicolás Alejandro 
Published: February 2018

Este artículo explora los factores que incentivan a las organizaciones regionales a sancionar países que experimentan retrocesos autoritarios en su proceso político. Tomando como caso de estudio las respuestas diplomáticas de la Organización de los Estados Americanos a nueve crisis políticas entre 1990 y 2017, el documento profundiza en las variables determinantes que han permitido la aplicación y efectividad de los distintos mecanismos de protección de la democracia en el hemisferio. El artículo formula tres aportes. Primero, que a mayor número de países democráticos al interior de la Organización, más probable es la aplicación de las sanciones. Segundo, que una conducta multilateral de Estados Unidos es mucho más efectiva que la conducta unilateral para restaurar la democracia. Tercero, que los países con coaliciones de golpe sólidas harán menos efectivas las sanciones.
Efecto antimicrobiano del aceite esencial de Citrus reticulata sobre Fusobacterium nucleatum asociada a enfermedad periodontal
Authors: Pardo Cindy Giohanna , Monsalve Gladys Stella , Tupaz Erira Herlinto Alveiro , Espinosa Villamizar Yeison , Jaramillo Gloria Isabel 
Published: February 2018

LLa clorhexidina como tratamiento de la enfermedad periodontal ha logrado efectos bactericidas sobre periodontopatógenos y biopelícula oral. Su uso genera efectos adversos, por lo tanto se presentan alternativas naturales con efecto antimicrobiano similar. Los aceites esenciales han demostrado efectividad en el control de la placa dental, sin los efectos adversos de la clorhexidina. El objetivo de este estudio fue determinar el efecto bacteriostático y bactericida del aceite esencial de mandarina contra Fusobacterium nucleatum. Se realizó extracción por expresión del aceite esencial de cáscaras de mandarina (variedades Arrayana y Oneco). Se evaluaron concentraciones al 20%, 40%, 60%, 80% y 100% del aceite esencial diluido en Tween al 0,02%. El efecto bacteriostático y bactericida se determinó por pruebas de sensibilidad antimicrobiana por difusión en disco. Como control positivo se utilizó Clorhexidina 0,2% y agua como control negativo. Se midió halo de inhibición (mm) y se determinó ausencia o presencia de crecimiento bacteriano a partir de unidades formadoras de colonias. Para comparación de proporciones de la actividad bacteriostática y bactericida, se realizó prueba de Fisher y T student (IC 95% p = 0,05). El halo de inhibición a una concentración del 100% mostró comportamiento similar a clorhexidina (p<0,05). Concentraciones al 100% y 80% fueron bactericidas, al 60%, 40% y 20% presentaron comportamiento bacteriostático. No se encontraron diferencias significativas en las proporciones de inhibición entre las dos variedades de mandarina (p>0,05). El uso de aceites esenciales de mandarina podría ser una alternativa complementaria al tratamiento de la enfermedad periodontal.
Efectos de nitratos y sacarosa en la propagación in vitro de tres variedades de papa nativa
Authors: Tacoronte Melangel , Vielma A. María , Olivo Auxiliadora , Chacín Nancy 
Published: February 2018

En Venezuela es prioridad rescatar las papas nativas por representar un gran alimento y un valioso recurso genético. Pero, desafortunadamente estas papas fueron desplazadas por variedades comerciales introducidas y las pocas semillas existentes están degeneradas y reutilizadas en continuos ciclos de siembra, No obstante, estandarizar las condiciones del cultivo aséptico es garantía de “semillas” rehabilitadas con mejor calidad fitosanitaria. Se planteó, entonces investigar el efecto de distintas concentraciones de nitratos y sacarosa en la propagación in vitro de variedades venezolanas ̀̀Cucubaʹ ̀̀Arbolona Negraʹ y ̀̀Rosadaʹ. Segmentos uninodales fueron cultivados e incubados en fotoperíodo de16 horas de luz (76 μmol m-2 s-1) y temperatura 19º C ± 1. Fue implementado el diseño estadístico factorial, estableciendo tres tratamientos partiendo del medio básico Murashige & Skoog (MS), sólido. Hubo un efecto significativo entre los tratamiento, al menos una de las medias es diferente a las otras, para las tres variedades la mayor inducción de crecimiento ocurrió, al modificar MS aumentando sus concentraciones de nitrato de amonio a 1,98 g L-1, nitrato de potasio 2,28 g L-1y bajando sacarosa a 20 g L-1, los vástagos desarrollaron 5,82 cm. de longitud promedio y las raíces 3 cm. Mientras, el MS (tratamiento control), presentó vástagos de 2,94cm. longitud promedio y sin enraizar. Entre las variedades ̀̀Cucuba´ obtuvo el mayor crecimiento. Posteriormente, las vitroplántulas resultantes, tratadas en MS líquido, con sacarosa al 8 % fueron inducidas a producir microtubérculos a los 90 días. Obteniendo así resultados prometedores para la propagación in vitro de las papas nativas.
Terapias Celulares y Productos de Ingeniería de Tejidos para el Tratamiento de Lesiones Condrales de Rodilla
Authors: Flórez Cabrera Adriana , González Duque Martha Isabel , Fontanlla Marta Raquel 
Published: February 2018

El cartílago articular es un tejido vulnerable a las lesiones de diferente etiología; siendo uno de los más afectados, el cartílago de la rodilla. Aunque la mayoría de los tratamientos convencionales reducen los síntomas, generalmente conducen a la formación de fibrocartílago; el cual, posee características diferentes a las del cartílago hialino de las articulaciones. Son pocas las aproximaciones terapéuticas que promueven el reemplazo del tejido dañado por cartílago hialino funcional; las más exitosas son las denominadas terapias avanzadas, que aplican células y productos de ingeniería de tejidos con el fin de estimular la regeneración del cartílago. La mayoría de ellas se basan en colocar soportes hechos con biomateriales de diferente origen, que sembrados o no con células exógenas o endógenas, reemplazan al cartílago dañado y promueven su regeneración. Este trabajo revisa algunas de las aproximaciones terapéuticas enfocadas en la regeneración del cartílago articular de rodilla; así como, los biomateriales más empleados en la elaboración de soportes para terapia celular e ingeniería de tejido cartilaginoso.