Estimaciones de los determinantes de los ingresos laborales en Colombia con consideraciones diferenciales para asalariados y cuenta propia

La literatura sobre determinantes de los ingresos laborales ha evolucionado en sus fundamentos teóricos, metodológicos y estimaciones empíricas. Colombia no ha sido ajena a este proceso, pero su evolución, notoria en fertilidad, ha venido relajándose en rigor conceptual: se tiende a considerar a los cuenta propia y asalariados como categorías relativamente semejantes. Para mostrar el efecto de dicha relajación realizamos estimaciones conjuntas de determinantes del ingreso laboral para ocupados asalariados y cuenta propia, y luego las contrastamos con estimaciones más detalladas y desagregadas ilustrando los sesgos efectivos que se generan si no se tienen en cuenta las características laborales de los ocupados cuenta propia y asalariado.

Estructura salarial y segmentación en el mercado laboral de Colombia: un análisis de las siete principales ciudades, 2001-2005

Este documento se concentra en el estudio de las diferencias salariales mediante la comparación de las distribuciones de los salarios para las siete principales ciudades colombianas en el periodo 2001-2005 con datos de la Encuesta Continua de Hogares. Se detectan diferencias significativas que se explican a la luz de la teoría del capital humano y de segmentación laboral; mediante la estimación de ecuaciones de salarios a partir de las características socioeconómicas de los trabajadores junto con efectos particulares para región y rama de actividad económica que resultan significativos dando evidencia de segmentación del mercado laboralen Colombia. El componente de los salarios que es particular a la región y a la actividad económica se explica a partir de variables macroeconómicas como el crecimiento económico, la dotación sectorial de factores, el costo de vida y el desempleo a nivel regional.

Modeling Habitat Associations for the Common Loon (Gavia immer) at Multiple Scales in Northeastern North America

Common Loon (Gavia immer) is considered an emblematic and ecologically important example of aquatic-dependent wildlife in North America. The northern breeding range of Common Loon has contracted over the last century as a result of habitat degradation from human disturbance and lakeshore development. We focused on the state of New Hampshire, USA, where a long-term monitoring program conducted by the Loon Preservation Committee has been collecting biological data on Common Loon since 1976. The Common Loon population in New Hampshire is distributed throughout the state across a wide range of lake-specific habitats, water quality conditions, and levels of human disturbance. We used a multiscale approach to evaluate the association of Common Loon and breeding habitat within three natural physiographic ecoregions of New Hampshire. These multiple scales reflect Common Loon-specific extents such as territories, home ranges, and lake-landscape influences. We developed ecoregional multiscale models and compared them to single-scale models to evaluate model performance in distinguishing Common Loon breeding habitat. Based on information-theoretic criteria, there is empirical support for both multiscale and single-scale models across all three ecoregions, warranting a model-averaging approach. Our results suggest that the Common Loon responds to both ecological and anthropogenic factors at multiple scales when selecting breeding sites. These multiscale models can be used to identify and prioritize the conservation of preferred nesting habitat for Common Loon populations.

Establishing Lagrangian connections between observations within air masses crossing the Atlantic during the International Consortium for Atmospheric Research on Transport and Transformation experiment

The ITCT-Lagrangian-2K4 (Intercontinental Transport and Chemical Transformation) experiment was conceived with an aim to quantify the effects of photochemistry and mixing on the transformation of air masses in the free troposphere away from emissions. To this end, attempts were made to intercept and sample air masses several times during their journey across the North Atlantic using four aircraft based in New Hampshire (USA), Faial (Azores) and Creil (France). This article begins by describing forecasts from two Lagrangian models that were used to direct the aircraft into target air masses. A novel technique then identifies Lagrangian matches between flight segments. Two independent searches are conducted: for Lagrangian model matches and for pairs of whole air samples with matching hydrocarbon fingerprints. The information is filtered further by searching for matching hydrocarbon samples that are linked by matching trajectories. The quality of these "coincident matches'' is assessed using temperature, humidity and tracer observations. The technique pulls out five clear Lagrangian cases covering a variety of situations and these are examined in detail. The matching trajectories and hydrocarbon fingerprints are shown, and the downwind minus upwind differences in tracers are discussed.

Possible Migration Routes Through Maine by Vernal Migrants

In this study we evaluate the possibility of two routes of migration into the state of Maine. The first possible route would be for migrants to continue along the coast, north of the Maine/New Hampshire border, and later swinging inland across the interior. The second path is for migrants who come up the east coast and straight into Maine, spreading across the state as they move north. In order to evaluate these possible routes we utilize a citizen-science project that measures the spring arrival dates of migrants according to the biophysical regions of Maine (Wilson 2007). Independent t-Tests and maps indicate that there is a trend of birds continuing along the coast before moving inland; six of the nine species show this pattern. Of the nine birds studied, only the eastern phoebe showed a significant trend of moving directly inland and moving across the state. Two birds show non-significant patterns of migration which could indicate insufficient data, or random migration patterns. The results are not conclusive because several of the biophysical regions have less reporting, and so the relationships among regions regarding arrival dates are skewed. Continued data collection and analysis is recommended.

A comunicação conectada ao uso das novas mídias no contexto educacional

Dissertação apresentada ao Programa de Pós-Graduação em Comunicação da Universidade Municipal de São Caetano do Sul

O computador no ensino de lígnua inglesa no CEFET/RN

The present study has as goal to analyze the aplicability of the computational technology as mediator in the english-speaking teaching in the Centro Federal de Educação Tecnológica do Rio Grande do Norte-CEFET/RN. The object of study was centered in the use of the computer incorporated in the teaching of English by four institution groups. The research was ruled metodologically in the study of case, adopting a qualitative and quantitative boarding of interpretative-reflexive mark. We support ourselves on a bibliographical literature revision that cares of the use of the computational technology matter into the class-room, aiming an education new practice, regarding the current reality conceptions in what we live in the technological education. We also use a referencial for a pedagogical action, trying to offer subsidies for a practice that provides the knowledges generation through the interaction, aiming a subject reflexive and critical education. For materialization of this study, we used esrutuctured action, as interviews for the teachers and students, besides the observations of the dayly in class-room, in order to get the necessary datas for analysis. During this study, we oserved that the use of the computer, while pedagogical support instrument in the english-speaking teaching, has acted like mediator of the teaching-learning process. The results demonstrate use of the computer use has been each more a practice adopted by other institution languages teachers. The conclusions confirm the hypothesis showed at the beginning of the work and evidence that the teachers are warden of forming thinking, reflexive and critical subjects. For that, they need to be prepared to face situations in which they can take the pedagogical practice to tune with the technological advances, consequently providing an effective technological education

Signal-flow graphs: Direct method of reduction and MATLAB implementation

Block diagrams and signal-flow graphs are used to represent and to obtain the transfer function of interconnected systems. The reduction of signal-flow graphs is considered simpler than the reduction of block diagrams for systems with complex interrelationships. Signal-flow graphs reduction can be made without graphic manipulations of diagrams, and it is attractive for a computational implementation. In this paper the authors propose a computational method for direct reduction of signal-flow graphs. This method uses results presented in this paper about the calculation of literal determinants without symbolic mathematics tools. The Cramer's rule is applied for the solution of a set of linear equations, A program in MATLAB language for reduction of signal-flow graphs with the proposed method is presented.