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A range of prepared titania nanoparticles were characterised by Brunauer-Emmett-Teller (BET) surface area, X-ray Diffraction (XRD), CPS Disc Centrifuge, Transmission Electron Microscope (TEM), Scanning Electron Micrographs (SEM), Thermogravimetric Analysis (TGA) and Fourier Transform Infrared Measurements (DRIFTS). In addition, the activities of the different catalysts were determined via rapid assessment methodologies like Microwave Dielectric Spectroscopy (MDS), Hydroxyl content, Phosphorescence and Chemiluminescence Spectroscopy and Isopropanol Oxidation Test and the data related to actual weathering properties of the pigments doped in metallocene polyethylene under dry and humid conditions. Quantum size effects, which lead to high surface areas and blue shifts and diminish electron–hole recombination, are used to explain the high activities of the nanoparticle products. In situ FTIR data and OH content determination show the presence of high contents of hydroxyl groups and large amounts of adsorbed water on TiO2 nanoparticles. The Disc Centrifuge results and BET surface area combined with the XRD particle size results show that a careful distinction between the crystal and aggregate sizes must be made in order to properly interpret the activity of TiO2 pigments. Aggregation of TiO2 pigments affects not only the surface area offered by the TiO2 but also the type of interaction between the light and the TiO2. The treatment conditions used for the crystallization of the primary material (precursor) in order to prepare the nanoparticle pigments, not only influenced the anatase crystal size but also other anatase properties (such as the surface hydroxylation, adsorbed water, recombination rate, aggregation state and type of structural defects). Chemiluminescence of the titania particles is discussed in light of potential surface active peroxidic species.

A range of prepared titania nanoparticles were characterised by Brunauer-Emmett-Teller (BET) surface area, X-ray Diffraction (XRD), CPS Disc Centrifuge, Transmission Electron Microscope (TEM), Scanning Electron Micrographs (SEM), Thermogravimetric Analysis (TGA) and Fourier Transform Infrared Measurements (DRIFTS). In addition, the activities of the different catalysts were determined via rapid assessment methodologies like Microwave Dielectric Spectroscopy (MDS), Hydroxyl content, Phosphorescence and Chemiluminescence Spectroscopy and Isopropanol Oxidation Test and the data related to actual weathering properties of the pigments doped in metallocene polyethylene under dry and humid conditions. Quantum size effects, which lead to high surface areas and blue shifts and diminish electron–hole recombination, are used to explain the high activities of the nanoparticle products. In situ FTIR data and OH content determination show the presence of high contents of hydroxyl groups and large amounts of adsorbed water on TiO2 nanoparticles. The Disc Centrifuge results and BET surface area combined with the XRD particle size results show that a careful distinction between the crystal and aggregate sizes must be made in order to properly interpret the activity of TiO2 pigments. Aggregation of TiO2 pigments affects not only the surface area offered by the TiO2 but also the type of interaction between the light and the TiO2. The treatment conditions used for the crystallization of the primary material (precursor) in order to prepare the nanoparticle pigments, not only influenced the anatase crystal size but also other anatase properties (such as the surface hydroxylation, adsorbed water, recombination rate, aggregation state and type of structural defects). Chemiluminescence of the titania particles is discussed in light of potential surface active peroxidic species.

A range of prepared titania nanoparticles were characterised by Brunauer-Emmett-Teller (BET) surface area, X-ray Diffraction (XRD), CPS Disc Centrifuge, Transmission Electron Microscope (TEM), Scanning Electron Micrographs (SEM), Thermogravimetric Analysis (TGA) and Fourier Transform Infrared Measurements (DRIFTS). In addition, the activities of the different catalysts were determined via rapid assessment methodologies like Microwave Dielectric Spectroscopy (MDS), Hydroxyl content, Phosphorescence and Chemiluminescence Spectroscopy and Isopropanol Oxidation Test and the data related to actual weathering properties of the pigments doped in metallocene polyethylene under dry and humid conditions. Quantum size effects, which lead to high surface areas and blue shifts and diminish electron–hole recombination, are used to explain the high activities of the nanoparticle products. In situ FTIR data and OH content determination show the presence of high contents of hydroxyl groups and large amounts of adsorbed water on TiO nanoparticles. The Disc Centrifuge results and BET surface area combined with the XRD particle size results show that a careful distinction between the crystal and aggregate sizes must be made in order to properly interpret the activity of TiO pigments. Aggregation of TiO pigments affects not only the surface area offered by the TiO but also the type of interaction between the light and the TiO. The treatment conditions used for the crystallization of the primary material (precursor) in order to prepare the nanoparticle pigments, not only influenced the anatase crystal size but also other anatase properties (such as the surface hydroxylation, adsorbed water, recombination rate, aggregation state and type of structural defects). Chemiluminescence of the titania particles is discussed in light of potential surface active peroxidic species.

In this work it was analyzed the reception of interpretive genres in Guayaquil Naval Academy based on the communicational impact of the Journalism Club from the newspaper El Telégrafo. It was sought to identify the processes of reception of the interpretive genres and their communicational incidence on students. The type of research is descriptive, the methodology is hermeneutical. In this investigation it was used nine research techniques, between quantitative and qualitative. Population is 357 students, it was used the probabilistic technique with mathematical equations to quantify the sample, which corresponds to 145 students. It was found out that there is a need to implement interpretive genres in the study area, to generate and develop cognitive skills, and design effective communication strategies in the institution. All these techniques will help to improve the learning process, Este trabajo analiza la recepción de los géneros periodísticos interpretativos en la Academia Naval Guayaquil, a partir de la incidencia comunicacional del Club de Periodismo del diario El Telégrafo. Se buscó identificar los procesos de recepción de los géneros interpretativos y su incidencia comunicacional en los estudiantes. El tipo de investigación fue descriptiva, con una metodología hermenéutica y nueve técnicas de investigación (entre cuantitativas y cualitativas). La población para la investigación fue de 357 estudiantes, usando una técnica probabilística con ecuaciones matemáticas para cuantificar la muestra, la misma que correspondió a 145 alumnos. A través de esto, se logró observar la necesidad de implementar los géneros interpretativos como tema de estudio, para generar y desarrollar las habilidades cognitivas y diseñar estrategias de comunicación efectivas dentro de la institución, todo esto enfocado a mejorar el proceso de aprendizaje.

Native bees contribute a considerable portion of pollination services for endemic as well as introduced plant species. Their decline has been attributed to several human-derived influences including global warming as well as the reduction, alteration, and loss of bees' habitat. With human expansion comes along the introduction of exotic plant species with negative impacts over native ecosystems. Anthropic effects may even have a deeper impact on communities adapted to extreme environments, such as high elevation habitats, where abiotic stressors alone are a natural limitation to biodiversity. Among these effects, the introduction of exotic plants and urbanization may have a greater influence on native communities. In this work, we explored such problems, studying the relationship between the landscape and its effect over richness and abundance of native bees from the subandean belt in the Andes mountain chain. Furthermore, we investigated the effects of exotic plant abundance on this high-altitude bee assemblage. Despite the landscape not showing an effect over bee richness and abundance, exotic plants did have a significant influence over the native bee assemblage. The abundance of exotic plants was associated with a relative increase in the proportion of small and medium bee species. Moreover, Halictidae was the only family that appeared to be favored by an increase in the abundance of exotic plant species. We discuss these results and the urgent need for further research of high-altitude environments due to their vulnerability and high endemicity.

In this work it was analyzed the reception of interpretive genres in Guayaquil Naval Academy based on the communicational impact of the Journalism Club from the newspaper El Telégrafo. It was sought to identify the processes of reception of the interpretive genres and their communicational incidence on students. The type of research is descriptive, the methodology is hermeneutical. In this investigation it was used nine research techniques, between quantitative and qualitative. Population is 357 students, it was used the probabilistic technique with mathematical equations to quantify the sample, which corresponds to 145 students. It was found out that there is a need to implement interpretive genres in the study area, to generate and develop cognitive skills, and design effective communication strategies in the institution. All these techniques will help to improve the learning process, Este trabajo analiza la recepción de los géneros periodísticos interpretativos en la Academia Naval Guayaquil, a partir de la incidencia comunicacional del Club de Periodismo del diario El Telégrafo. Se buscó identificar los procesos de recepción de los géneros interpretativos y su incidencia comunicacional en los estudiantes. El tipo de investigación fue descriptiva, con una metodología hermenéutica y nueve técnicas de investigación (entre cuantitativas y cualitativas). La población para la investigación fue de 357 estudiantes, usando una técnica probabilística con ecuaciones matemáticas para cuantificar la muestra, la misma que correspondió a 145 alumnos. A través de esto, se logró observar la necesidad de implementar los géneros interpretativos como tema de estudio, para generar y desarrollar las habilidades cognitivas y diseñar estrategias de comunicación efectivas dentro de la institución, todo esto enfocado a mejorar el proceso de aprendizaje.

OBJECTIVE: To assess the available data on the prevalence of metabolic syndrome (MS) in Latin-American countries. DESIGN: Systematic review. Searches were carried out in PubMed, ISIWeb, SCielo and Redalyc, using 'metabolic syndrome x' and 'prevalence' as keywords for titles and/or abstracts. Articles selected were cross-sectional studies in Latin-American countries, whose main objective was to study MS and whose study population is described below. MS must be determined using Adult Treatment Panel III criteria. Twelve studies with these criteria were selected, one of which was multi-centric. SETTING: Latin America. SUBJECTS: Apparently healthy subjects aged 18-65 years (including young adult, mature adult and elderly populations) of both genders. RESULTS: The general prevalence (weighted mean) of MS in Latin-American countries was 24·9 (range: 18·8-43·3) %. MS was slightly more frequent in women (25·3 %) than in men (23·2 %), and the age group with the highest prevalence of MS consisted of those over 50 years of age. The most frequent components of MS were low HDL cholesterol levels (62·9 %) and abdominal obesity (45·8 %). Similar outcomes were obtained from the multi-centre study on Latin-American populations analysed. CONCLUSIONS: The present review brings us closer to an understanding of the prevalence of MS in Latin-American countries. However, it is not possible to know the full scope of the problem, partly because data from some countries are not available, and because the methodological differences among the studies published up to the present limit a joint analysis of their results.

One of the challenges in the development of mineral processing simulators is modelling the liberation characteristics of particles produced by comminution circuits. Understanding the mineral characteristics of these particles is one of the keys to predicting their behaviour in separation circuits. Several researchers have noted the similarity of the liberation characteristics for a selected size fraction of particulate material, whether the fraction comes from a coarse material, such as the product from a jaw crusher, or a more finely ground material, such as the product from a ball mill. In most cases these observations were reported as an aside and were not the main focus of the published work. This observed behaviour has the potential to be a useful tool for modelling the particle characteristics in mineral comminution and separation circuits, particularly as we move towards the development of multi-component models. However, before the behaviour can be used widely we need to understand which ore types follow the observed pattern and which do not. The current work examines a range of ores and identifies which exhibit the pattern of similarity of composition for particles in a given size class that has been produced as the result of a variety of breakage conditions. The impact of mineralogy and texture on the evolution of liberation characteristics for both valuable and gangue minerals is discussed., One of the challenges in the development of mineral processing simulators is modelling the liberation characteristics of particles produced by comminution circuits. Understanding the mineral characteristics of these particles is one of the keys to predicting their behaviour in separation circuits. Several researchers have noted the similarity of the liberation characteristics for a selected size fraction of particulate material, whether the fraction comes from a coarse material, such as the product from a jaw crusher, or a more finely ground material, such as the product from a ball mill. In most cases these observations were reported as an aside and were not the main focus of the published work. This observed behaviour has the potential to be a useful tool for modelling the particle characteristics in mineral comminution and separation circuits, particularly as we move towards the development of multi-component models. However, before the behaviour can be used widely we need to understand which ore types follow the observed pattern and which do not. The current work examines a range of ores and identifies which exhibit the pattern of similarity of composition for particles in a given size class that has been produced as the result of a variety of breakage conditions. The impact of mineralogy and texture on the evolution of liberation characteristics for both valuable and gangue minerals is discussed.

En los primeros meses del año 1996 se hizo encuesta a 121 productores de frijol, ubicados en la región B-3 (Las Segovias) en Nicaragua, que comprende los departamentos de Estelí, Madriz y Nueva Segovia. El objetivo fue el de conocer las tasas de adopción de las variedades Estelí 90A, Estelí 908 y Estelí 150. Los resultados obtenidos muestran que en la región de estudio, el uso de variedades mejoradas es alto, ya que son cultivadas por 79.3 % de los productores en el 72.7 % del área sembrada con frijol (aproximadamente unas 16,600 ha). En las variedades mejoradas se destaca la utilización de Estelí 90A material que fue sembrado por el 54.2 % de los agricultores en el 55.5 % del área cultivada con éste tipo de genotipos. Le sigue en orden de importancia la variedad Estelí 908 y luego Estelí 150. En cuanto al patrón de difusión de las variedades Estelí, se encontró que en 1990 iniciaron con un 8 % de Índice de Aceptabilidad, hasta llegar a 74 % en las siembras de postrera de 1995-96, indicando que el potencial de difusión de estas variedades es excelente. Según los datos obtenidos con el estudio, bajo el supuesto de que la muestra entrevistada representa a la población de productores de frijol de la región, se infiere que del área total cultivada en postrera de 1995-96, el 69.5 % fue con las variedades Estelí, lo cual equivale a unas 16,000 ha. En concepto de los productores, las variedades Estelí son de alto potencial de rendimiento, de buena aceptación en el mercado y tolerantes al Tizón común (Xanthomonas campestris pv. Phaseolis) y sequía, aspectos que han contribuido positivamente para su difusión.

Technical assistance was given to Compañía Azucarera Hondureña, S.A. (Agro-Industrial Co.), Honduras, Central America, to determine if a campaign against noxious rodents to agriculture crops was needed. Several trappings were carried out at different places using snap traps to determine the population structure of rodents associated with the crop, and live traps to determine the index or density of the Sigmodon hispidus rat population, which was identified as being responsible for the damage to sugarcane. Results were 43.24% adult males, 14.86% young males, 31.41% adult females, and 10.47% young females. Of the adult females captured, 54.83% were pregnant with an average of 3 to 4 embryos per rat. A control demonstration combat was carried out at one of the experimental stations with a bait prepared with 2% zinc phosphide in a place where it had been previously determined there was a population of 39 rats per hectare. After such control, the population was reduced to 18 rats per hectare, which represents an efficiency of 53.85%. An evaluation of damages was also measured at different places to determine the degree of loss caused by the rats, which proved to be 22.79% damage. The size of the sample was estimated in 3 samples per hectare, with a level of confidence of 95%.

Technical assistance was given to Compañía Azucarera Hondureña, S.A. (Agro-Industrial Co.), Honduras, Central America, to determine if a campaign against noxious rodents to agriculture crops was needed. Several trappings were carried out at different places using snap traps to determine the population structure of rodents associated with the crop, and live traps to determine the index or density of the Sigmodon hispidus rat population, which was identified as being responsible for the damage to sugarcane. Results were 43.24% adult males, 14.86% young males, 31.41% adult females, and 10.47% young females. Of the adult females captured, 54.83% were pregnant with an average of 3 to 4 embryos per rat. A control demonstration combat was carried out at one of the experimental stations with a bait prepared with 2% zinc phosphide in a place where it had been previously determined there was a population of 39 rats per hectare. After such control, the population was reduced to 18 rats per hectare, which represents an efficiency of 53.85%. An evaluation of damages was also measured at different places to determine the degree of loss caused by the rats, which proved to be 22.79% damage. The size of the sample was estimated in 3 samples per hectare, with a level of confidence of 95%.