L'Univers

1881/08/05 (Numéro 5022).

Flora fanerogâmica não-arbórea do cerrado na Estação Ecológica de Assis, Estado de São Paulo

A vegetação de cerrado no Estado de São Paulo sobrevive em poucas áreas naturais remanescentes cuja flora, exceto pelas espécies arbóreas, é pouco conhecida. O presente estudo teve como objetivo caracterizar a flora fanerogâmica não-arbórea das diferentes fisionomias da vegetação (campo úmido, cerrado sensu stricto, cerradão e mata ciliar) na Estação Ecológica de Assis (22°33'65" e 22°36'68" S e 50°22'29" e 50°23'00" W), Estado de São Paulo, Brasil, e compará-la a outras áreas de cerrado no estado, para verificar possíveis endemismos ou a presença de espécies raras, que mereçam providências especiais de manejo para sua conservação. Nas diferentes fisionomias da vegetação no interior da unidade de conservação foram registradas 301 espécies fanerógamas não-arbóreas, pertencentes a 199 gêneros e 61 famílias. As famílias com os maiores números de espécies foram: Fabaceae, Asteraceae, Bignoniaceae e Poaceae. A riqueza de espécies foi decrescente do cerrado sensu stricto (146 espécies ou 48,8%), seguido pelo cerradão (48 espécies ou 15,9%), campo úmido (47 espécies ou 15,6%) e, por último, a mata ciliar (15 espécies ou 5,0%). Comparada às outras áreas analisadas de cerrado no Estado de São Paulo, a diversidade da flora não-arbórea local é elevada. O alto nível de ocorrências únicas para as formas de vida inventariadas (102 espécies ou 34%) tem sido igualmente observado em outros estudos, indicando que ou os endemismos são mais comuns para espécies vegetais não-arbóreas do que para arbóreas ou os métodos de inventário não têm sido adequados para representar toda a riqueza dessas espécies em cada local. Estratégias de conservação e inventários botânicos devem valorizar especialmente a flora não-arbórea, uma vez que as espécies da flora arbórea apresentam-se mais amplamente distribuídas e melhor inventariadas.

L'Écho de Paris

1898/02/24 (Numéro 5022).

Oeuvres de JEAN JUVENAL DES URSINS.

Contient : 1 Épître sur le traité de paix que le roi de France voulait faire avec le roi d'Angleterre ; 2 Épître ou discours sur la paix d'Arras

Resoluciones Cámara de Comercio de Bogotá

Doctrina

Pollen and grain size records in abyssal sediments of the northwest Pacific Ocean as proxies of Plio-Pleistocene climate change /

A distinctive period of global change occurred during the PUocene between the warm Miocene and subsequent Quaternary cooling. Samples from Ocean Drilling Project Site 11 79 (-5586 mbsl, 41°4'N, 159°57'E), Site 881 (-5765 mbsl, 47°6.133'N, 161°29.490'E) and Site 882 (-3255 mbsl, 50°22'N, 167°36'E) were studied to determine the magnitude and composition ofterrigenous flux to the western mid-latitude North Pacific and its relation to climate change in East Asia since the mid-Pliocene. Dust-sized particles (including pollen), sourced from the arid regions and loess plateaus in East Asia are entrained by prevailing westerly winds and transported to the midlatitude northwest North Pacific Ocean. This is recorded by peaks in the total concentration of pollen and spores, as well as the mean grain size of allochthonous and autochthonous silicate material in abyssal marine sediments. Aridification of the Asian interior due to the phased uplift of the Himalayan-Tibetan Plateau created the modem East Asian Monsoon system dominated by a strengthening of the winter monsoon. The winter monsoon is further enhanced during glacials due to the expansion of desert and steppe environments at the expense ofwoodlands and forests recorded by the composition of palynological assemblages. The late Pliocene-Pleistocene glacials at ODP Sites 1 179, 881, and 882 are characterized by increases in grain size, magnetic susceptibility, pollen and spore concentrations around 3.5-3.3, 2.6-2.4, 1.7-1.6, and 0.9-0.7 Ma (ages based on magnetostratigraphic and biostratigraphic datums). The peaks during these times are relatively rich in pollen taxa derived primarily from steppe and boreal vegetation zones, recording cool, dry climates. The overall size increase of sediment and abundance of terrestrial palynomorphs record enhanced wind strength. The increase in magnitude of pollen and spore concentrations as well as grain size record global cooling and Northern Hemisphere glaciation. The peaks in grain size as well as pollen and spore abundance in marine sediments correlate with the mean grain size of loess in East Asia, consistent with the deflation of unarmoured surfaces during glacials. The transport of limiting nutrients to marine environments enhanced sea surface productivity and increased the rate of sediment accumulation.

Gestión de proyecto. Propuesta de conjunto habitacional popular como estrategia de desarrollo comunitario y regeneración con enfoque administrativo para el área metropolitana de Monterrey.

Tesis (Maestría en Administración de la Construcción) UANL, 2010.

Understanding deep architectures and the effect of unsupervised pre-training

Cette thèse porte sur une classe d'algorithmes d'apprentissage appelés architectures profondes. Il existe des résultats qui indiquent que les représentations peu profondes et locales ne sont pas suffisantes pour la modélisation des fonctions comportant plusieurs facteurs de variation. Nous sommes particulièrement intéressés par ce genre de données car nous espérons qu'un agent intelligent sera en mesure d'apprendre à les modéliser automatiquement; l'hypothèse est que les architectures profondes sont mieux adaptées pour les modéliser. Les travaux de Hinton (2006) furent une véritable percée, car l'idée d'utiliser un algorithme d'apprentissage non-supervisé, les machines de Boltzmann restreintes, pour l'initialisation des poids d'un réseau de neurones supervisé a été cruciale pour entraîner l'architecture profonde la plus populaire, soit les réseaux de neurones artificiels avec des poids totalement connectés. Cette idée a été reprise et reproduite avec succès dans plusieurs contextes et avec une variété de modèles. Dans le cadre de cette thèse, nous considérons les architectures profondes comme des biais inductifs. Ces biais sont représentés non seulement par les modèles eux-mêmes, mais aussi par les méthodes d'entraînement qui sont souvent utilisés en conjonction avec ceux-ci. Nous désirons définir les raisons pour lesquelles cette classe de fonctions généralise bien, les situations auxquelles ces fonctions pourront être appliquées, ainsi que les descriptions qualitatives de telles fonctions. L'objectif de cette thèse est d'obtenir une meilleure compréhension du succès des architectures profondes. Dans le premier article, nous testons la concordance entre nos intuitions---que les réseaux profonds sont nécessaires pour mieux apprendre avec des données comportant plusieurs facteurs de variation---et les résultats empiriques. Le second article est une étude approfondie de la question: pourquoi l'apprentissage non-supervisé aide à mieux généraliser dans un réseau profond? Nous explorons et évaluons plusieurs hypothèses tentant d'élucider le fonctionnement de ces modèles. Finalement, le troisième article cherche à définir de façon qualitative les fonctions modélisées par un réseau profond. Ces visualisations facilitent l'interprétation des représentations et invariances modélisées par une architecture profonde.

Strait dynamics of tropical tidal inlets

The dynamics and associated stability analysis of tidal inlets situated on the southwest coast of India, namely Andhakaranazhi (90 45 J OO JJN and 760 17 J 29 JJ E) and the other at Cochin harbour inlet (90 58 1 04 J1N and 760 14 1 50 1J E) have beenconducted. A detailed study on the inlet regime of Cochin barmouth (permanent in nature) was attempted so as to elucidate information on: (a) channel characteristics (b) tidal hydraulics and (c) stability of the inlet. In this connection, a naturally occurring seasonal sandbar formation at Andhakaranazhi, near Sherthallay, about 20 km south of Cochin inlet, was also chosen as a site ofstudy brought out conclusively the dynamical study. The aspects of ( 1) tidal influx/out flux (2) channel morphology (3) sedimentation regime and (4) stability and factors related to stability of these locations. The above aspects are supported by suitable mathematical formulations to describe the associated coastal processes, wherever applicable

Development of Electrochemical and Fluorescent Sensors

Chemical sensors have growing interest in the determination of food additives, which are creating toxicity and may cause serious health concern, drugs and metal ions. A chemical sensor can be defined as a device that transforms chemical information, ranging from the concentration of a specific sample component to total composition analysis, into an analytically useful signal. The chemical information may be generated from a chemical reaction of the analyte or from a physical property of the system investigated. Two main steps involved in the functioning of a chemical sensor are recognition and transduction. Chemical sensors employ specific transduction techniques to yield analyte information. The most widely used techniques employed in chemical sensors are optical absorption, luminescence, redox potential etc. According to the operating principle of the transducer, chemical sensors may be classified as electrochemical sensors, optical sensors, mass sensitive sensors, heat sensitive sensors etc. Electrochemical sensors are devices that transform the effect of the electrochemical interaction between analyte and electrode into a useful signal. They are very widespread as they use simple instrumentation, very good sensitivity with wide linear concentration ranges, rapid analysis time and simultaneous determination of several analytes. These include voltammetric, potentiometric and amperometric sensors. Fluorescence sensing of chemical and biochemical analytes is an active area of research. Any phenomenon that results in a change of fluorescence intensity, anisotropy or lifetime can be used for sensing. The fluorophores are mixed with the analyte solution and excited at its corresponding wavelength. The change in fluorescence intensity (enhancement or quenching) is directly related to the concentration of the analyte. Fluorescence quenching refers to any process that decreases the fluorescence intensity of a sample. A variety of molecular rearrangements, energy transfer, ground-state complex formation and collisional quenching. Generally, fluorescence quenching can occur by two different mechanisms, dynamic quenching and static quenching. The thesis presents the development of voltammetric and fluorescent sensors for the analysis of pharmaceuticals, food additives metal ions. The developed sensors were successfully applied for the determination of analytes in real samples. Chemical sensors have multidisciplinary applications. The development and application of voltammetric and optical sensors continue to be an exciting and expanding area of research in analytical chemistry. The synthesis of biocompatible fluorophores and their use in clinical analysis, and the development of disposable sensors for clinical analysis is still a challenging task. The ability to make sensitive and selective measurements and the requirement of less expensive equipment make electrochemical and fluorescence based sensors attractive.

Efectos de un estresor acad??mico sobre las respuestas psicol??gica e inmune en j??venes

Resumen tomado de la publicaci??n

Prevalencia de sintomatología musculoesquelética en trabajadores de una empresa avícola de Cundinamarca en el año 2013

RESUMEN Objetivos Determinar la prevalencia de sintomatología musculoesquelética en trabajadores en una empresa avícola de Cundinamarca en el año 2013. Metodología Se eligió un diseño observacional, descriptivo, transversal mediante un método de recolección de datos a través de una herramienta estandarizada el “Cuestionario Nórdico musculoesquelético”(1), se adicionaron datos sociodemográficos como edad, género, cargo laboral y antigüedad laboral. El análisis del presente estudio se realizó a través de herramienta informática estadística “EPIINFO versión 3.5.4”(2). Resultados Del total de la población estudiada en la empresa avícola de Cundinamarca que fue de 229 trabajadores, se excluyeron 65 trabajadores por llevar menos de un año de labor en la empresa; quedando 164 trabajadores de las que correspondieron al género femenino 36.0% (n=58) y del género masculino 64.0% (n=105). El promedio de edad fue de 38.1 ± 9.4 años con un mínimo de 18 años y un máximo de 56 años. La distribución de acuerdo a nivel educativo principalmente fueron bachilleres con el 48.8% (n=80) y primaria fueron 34.8% (n=57). La prevalencia de síntomas osteomusculares en los últimos 12 meses por segmentos corporales fue más frecuente en manos y muñecas con un 65.2%, seguido del segmento de columna lumbar con un 48.0%; por número de segmentos comprometidos se encontró una prevalencia de 4 o más segmentos del 52.2%. Conclusión La prevalencia global de sintomatología musculoesquelética de nuestro estudio aunque coincidente con la literatura, evidencia a nivel de segmentos diferencias importantes como en el de manos muñecas, donde la séptima encuesta nacional de condiciones de trabajo del Instituto Nacional de Higiene en el Trabajo de España (INHT) reporta el 10.8%(3). En nuestro estudio se encontró una mayor prevalencia de síntomas en 4 o más segmentos comprometidos, comparado con el estudio Prevalence of multisite musculoskeletal symptoms: a French cross-sectional working population-based study que reporta una prevalencia para 4 o más segmentos del 27.0% al 35.0%(12), lo que nos hace pensar en la coexistencia de múltiples factores de riesgos ergonómicos.

Prevalencia de síntomas osteomusculares en trabajadores del Congreso de la República de Colombia durante el 2013

This study followed a design of observational, cross-sectional descriptive. In a sample of 59 workers of the Congress of the Republic of Colombia, to which we applied a survey based on the Nordic questionnaire (1) and demographic information: age, gender, position and seniority; as well as height and weight to estimate body mass index (BMI). For the analysis of the information frequency, percentage and units of central tendency were used. The data processing was performed with the software Stat Info Vocational (2) and Excel version 2013.