Evaluating the impact of an environmental education programme; an empirical study in Mexico.

This study draws on information from 11 in-depth interviews, two focus groups and 72 written questionnaires to evaluate an extra-curricular environmental education programme on forestry designed for preparatory school students from a small rural community in Mexico. Specifically, the study assessed the impact of the programme on the ecological knowledge of 72 students. Qualitative feedback suggests that students learnt about forestry, acquired greater awareness of the importance of conservation for the local environment and enjoyed the participatory teaching methods used in the programme. Quantitative results show a positive and significant association between the number of times a student participated in the programme and the student&rsquo;s ecological knowledge. Students who participated in the programme once had a 16.3% higher knowledge on ecological concepts and knew, on average, 1.5 more local forest plants than students who never attended it (p&lt;.001). Findings suggest that the inclusion of participatory environmental education programmes in preparatory schools would improve the acquisition of ecological knowledge. Further research could consider the consistency of the findings by replicating participatory methods presented here and by using an experimental research design.<br /

Estrategias gerenciales con criterios ergonómicos y de prevención de riesgos laborales, para una fábrica de calzados en Barranquilla

Administración de EmpresasThe research conducted aims to design ergonomic management strategies and Occupational Risk Prevention (ORP) criteria for a shoe factory in Barranquilla. The research, in the positivist paradigm with a predominantly quantitative, based on fieldwork, descriptive, transactional, non-experimental design, and using an analytical-explanatory documentary component, from the qualitative allowed based information the final development. An instrument of data collection consisting of notes of observation was used. The study population consisted of shoe factories in downtown of Barranquilla with increased production to two thousand weekly pairs and probabilistic intentional sample. The results show them the significant detachment of workers to the inherent aspects of health care, from observing locative factors in their jobs. It helps with the presentation of the strategies that the manager must follow to get continuous improvement regarding ergonomics and (ORP), and a value added tool for the manager, represented by tabs systematic observation.La investigación que se realiza tuvo por objetivo diseñar las estrategias gerenciales con criterios ergonómicos y de prevención de riesgos laborales (PRL), para una fábrica de calzados en Barranquilla. El tipo de investigación, en el paradigma positivista con un carácter dominantemente cuantitativo, se basó en un trabajo de campo, descriptivo y transaccional, de diseño no experimental, utilizando además un componente documental analítico-explicativo, que desde lo cualitativo permitió la información base para el desarrollo final. Se utilizó un instrumento de recolección de datos, constituido por fichas de observación. La población de estudio estuvo constituida por fábricas de calzado del centro de Barranquilla con una producción mayor a los dos mil pares semanales y la muestra fue no probabilística intencionada. Los resultados demostraron el desapego significativo de los trabajadores hacia los aspectos inherentes al cuidado de su salud, desde la observación de factores locativos en sus puestos de trabajo. Se contribuye con la presentación de las estrategias que el gerente debe seguir para la mejora continua relacionada con la ergonomía y PRL, además de un valor agregado con una herramienta para el gerente, representada por las fichas de observación sistemática

Estimating flooded area and mean water level using active and passive microwaves: the example of Paraná River Delta floodplain

This paper describes a procedure to estimate both the fraction of flooded area and the mean water level in vegetated river floodplains by using a synergy of active and passive microwave signatures. In particular, C band Envisat ASAR in Wide Swath mode and AMSR-E at X, Ku and Ka band, are used. The method, which is an extension of previously developed algorithms based on passive data, exploits also model simulations of vegetation emissivity. The procedure is applied to a long flood event which occurred in the Paraná River Delta from December 2009 to April 2010. Obtained results are consistent with in situ measurements of river water level

Estudio del proceso de crecimiento del cultivo del tomate

Para conocer la densidad poblacional óptimay obtener el mayor rendimiento en el cultivo deltomate en el Valle del Sinú medio, se hizo una investigaciónmediante diseño completamente al azar con cuatrotratamientos (densidades poblacionales de 20.000,25.000, 33.333 y 50.000 plantas∙ha -1) y tres repeticiones.Se tomaron las medidas directas: altura de planta, númerode hojas, área foliar, número de frutos y rendimiento.También se calcularon los índices de crecimiento: tasa decrecimiento del cultivo (TCC), tasa de asimilación neta(TAN), tasa relativa de crecimiento (TRC), índice deárea foliar (IAF) y duración del área foliar (DAF). Con lapoblación de 50.000 plantas∙ha -1 se obtuvo mayor alturade planta, con un promedio de 240,33 cm a los 120 díasdespués del trasplante; mayor número de hojas, con unpromedio de 196,7 a los 120 días, mayor área foliar, conun promedio de 8.109,73 cm 2, a los 105 días, y el mayorrendimiento de frutos por planta, con un promedio de1.699,27 g. Este mismo tratamiento (50.000 plantas∙ha -1)presentó los más altos valores medios de (a) TCC (40,88g∙m -2∙día-1 a los 105 días después del trasplante), (b) TAN(0,00343 g∙cm -2∙día-1 a los 75 días), (c) TRC (0,1532g∙g -1∙día-1, a los 45 días), (d) IAF (4,04824 a los 105días), y (e) DAF (56,37075 días, a los 120 días)

Behavior of multitemporal and multisensor passive microwave indices in Southern Hemisphere ecosystems

©2014. American Geophysical Union. All Rights Reserved. This study focused on the time series analysis of passive microwave and optical satellite data collected from six Southern Hemisphere ecosystems in Australia and Argentina. The selected ecosystems represent a wide range of land cover types, including deciduous open forest, temperate forest, tropical and semiarid savannas, and grasslands. We used two microwave indices, the frequency index (FI) and polarization index (PI), to assess the relative contributions of soil and vegetation properties (moisture and structure) to the observations. Optical-based satellite vegetation products from the Moderate Resolution Imaging Spectroradiometer were also included to aid in the analysis. We studied the X and Ka bands of the Advanced Microwave Scanning Radiometer-EOS and Wind Satellite, resulting in up to four observations per day (1:30, 6:00, 13:30, and 18:00-h). Both the seasonal and hourly variations of each of the indices were examined. Environmental drivers (precipitation and temperature) and eddy covariance measurements (gross ecosystem productivity and latent energy) were also analyzed. It was found that in moderately dense forests, FI was dependent on canopy properties (leaf area index and vegetation moisture). In tropical woody savannas, a significant regression (R2) was found between FI and PI with precipitation (R2->-0.5) and soil moisture (R2->-0.6). In the areas of semiarid savanna and grassland ecosystems, FI variations found to be significantly related to soil moisture (R2->-0.7) and evapotranspiration (R2->-0.5), while PI varied with vegetation phenology. Significant differences (p-<-0.01) were found among FI values calculated at the four local times. Key Points Passive microwave indices can be used to estimate vegetation moisture Microwave observations were supported by flux data Passive microwave indices could be used to estimate evapotranspiratio

Jacalones y permisos: la instalación de cinematógrafos entre 1898-1904

Explica la instalación de los cines ambulantes en las plazuelas de la ciudad de México en el periodo señalado. Se trata de los "jacalones", construcciones de madera y lona parecidas a las carpas circenses. La información procede del Archivo Histórico del Ex-Ayuntamiento de la ciudad de México. El entonces Ayuntamiento concedía los permisos de instalación a los nuevos empresarios de cine, siempre y cuando satisficieran ciertos requisitos reglamentarios y pagaran un gravamen. Pese a ser hoy prácticamente desconocidos, los peticionarios locales lograron que el cine se difundiera entre la gente del pueblo y no quedara confinado a los ámbitos de la aristocracia y la clase media porfirianas. Aquí se hace su relación y se comentan algunas de las circunstancias en que instalaron sus cinematógrafosThe text explains the installation of itinerant movies in the small squares of Mexico City, in the years indicated. They were knowned as the Jacalones (from "jacal", mexican rustic cabin), wtxxi and canvas buildings, similar as circus tents. The information prtx eeds from the Archivo Histórico del Ex-Ayuntamiento de la ciudad de Mexico. Tire former Ayuntamiento gave the licences to the new movie managers, under certains requeriments and the pay of a tribute. Eventhough they are practically unknown at the present time, their labor in the Jacalones achieve the spreading of cinema to the common people and, in these way, the invention scapes from the exclusive precints of Porfirian aristocracy and medium classes public. Tírese text includes a list of the jacalones and information about the particular conditions in which they were installed

Water Splitting Electrocatalysis within Layered Inorganic Nanomaterials

The conversion of solar energy into chemical fuel is one of the “Holy Grails” of twenty-first century chemistry. Solar energy can be used to split water into oxygen and protons, which are then used to make hydrogen fuel. Nature is able to catalyze both the oxygen evolution reaction (OER) and the hydrogen evolution reaction (HER) required for the conversion of solar energy into chemical fuel through the employment of enzymes that are composed of inexpensive transition metals. Instead of using expensive catalysts such as platinum, cheaper alternatives (such as cobalt, iron, or nickel) would provide the opportunity to make solar energy competitive with fossil fuels. However, obtaining efficient catalysts based on earth-abundant materials is still a daunting task. In this chapter, we review the advancements made with zirconium phosphate (ZrP) as a support for earth-abundant transition metals for the OER. Our studies have found that ZrP is a suitable support for transition metals as it provides an accessible surface where the OER can occur. Further findings have also shown that exfoliation of ZrP increases the availability of sites where active species can be adsorbed and performance is improved with this strategy

Confined two-dimensional fermions at finite density

We introduce the chemical potential in a system of two-dimensional massless fermions, confined to a finite region, by imposing twisted boundary conditions in the Euclidean time direction. We explore in this simple model the application of functional techniques which could be used in more complicated situations.Comment: 15 pages, LaTe

A Molecular Platinum Cluster Junction: A Single-Molecule Switch

We present a theoretical study of the electronic transport through single-molecule junctions incorporating a Pt6 metal cluster bound within an organic framework. We show that the insertion of this molecule between a pair of electrodes leads to a fully atomically engineered nano-metallic device with high conductance at the Fermi level and two sequential high on/off switching states. The origin of this property can be traced back to the existence of a HOMO which consists of two degenerate and asymmetric orbitals, lying close in energy to the Fermi level of the metallic leads. Their degeneracy is broken when the molecule is contacted to the leads, giving rise to two resonances which become pinned close to the Fermi level and display destructive interference.Comment: 4 pages, 4 figures. Reprinted (adapted) with permission from J. Am. Chem. Soc., 2013, 135 (6), 2052. Copyright 2013 American Chemical Societ