Robust transitivity and domination for endomorphisms displaying critical points

We show that robustly transitive endomorphisms of a closed manifolds must have a non-trivial dominated splitting or be a local diffeomorphism. This allows to get some topological obstructions for the existence of robustly transitive endomorphisms. To obtain the result we must understand the structure of the kernel of the differential and the recurrence to the critical set of the endomorphism after perturbation.Comment: We rewrote Lemmas 2.7 and 4.7 in order to be clearer. we also would like to thanks the referee for their suggestion and comment

Prospeccion de la necesidad de formacion de tecnicos en servicios turisticos para la explotacion turistica del Radal Siete Tazas : Caso Liceo Polivalente de Molina

180 p.La presente investigación tiene como propósito prospectar la necesidad de formación de técnicos en turismo en el Liceo Polivalente de Molina, para la explotación turística del Radal Siete Tazas. Para dar cumplimiento a los objetivos planteados se realizó una investigación cualitativa y cuantitativa. La investigación cualitativa permitió determinar la fuente de financiamiento para la capacitación a los profesores, a través de entrevistas en profundidad con el director comunal de educación de Molina; competencias requeridas por los egresados de la carrera, información obtenida a través del Ministerio de Educación; costo del programa de capacitación de los profesores, objetivo que se pretendió lograr a través de entrevistas a docentes del área turismo; las actividades turísticas que se pueden realizar dentro del Radal Siete Tazas, otorgadas por la Ilustre Municipalidad de Molina y consultas realizadas a CONAF. Dentro de la investigación cuantitativa se diseñaron dos encuestas estadísticas, una dirigida a los alumnos del liceo, para determinar el conocimiento que poseen sobre el Radal Siete Tazas y grado de interés por la carrera de servicios turísticos. La segunda encuesta fue dirigida a los profesores del establecimiento, cuya finalidad es determinar el grado de interés para capacitarse en turismo. Previo a ejecutar el trabajo en terreno, se realizó un piloteo de cada encuesta. En el caso de los alumnos se debió extraer una muestra de la población en estudio y en el caso de los profesores se realizó un censo. Además, fue necesario consultar a las agencias y operadores de tour, como también a las instituciones educacionales que imparten cameras de turismo. Finalmente, se determinó un alto grado de interés de los alumnos por la carrera propuesta. El técnico-profesional debe poseer alto conocimiento cultural, histórico, geográfico y administrativo en el ámbito turístico, además debe mantener buenas relaciones sociales y un manejo de idiomas. Por otra parte los docentes se encuentran interesados en capacitarse para impartir dicha carrera. El Ministerio de Educación otorga el financiamiento respectivo para los programas de capacitación, junto con la Ilustre Municipalidad de Molina, la cual concursa para obtener mas financiamiento de otros fondos estatales. Además se logro determinar la alta demanda y una oferta limitada del lugar en estudio. Las palabras claves del estudio son: necesidad, turismo, capacitación y financiamient

Analysing the impacts of individual-level factors on public transport usage during the COVID-19 pandemic: A comprehensive literature review and meta-analysis

Public transport (PT) usage was severely impacted during the COVID-19 pandemic, resulting in up to a 90% reduction in many cities in 2020. Numerous studies have been conducted since then to determine the relationship between individual-level factors (such as gender, attitudes, etc.) and the decrease in PT usage during the pandemic. Despite the evidence provided, findings are dispersed, and for several factors contradictory, making it challenging to reach any generalised conclusion. Furthermore, a comprehensive comparison of the effect sizes among travellers’ factors affecting PT use during this period is yet to be compiled. This paper aims to address these gaps by systematically reviewing the existing evidence and synthesising the effect sizes of travellers’ factors through a meta-analysis. We first identified 36 studies that statistically assessed the contribution of 15 individual-level factors on PT usage during the COVID-19 pandemic. By merging the empirical evidence of those studies, the direction of the association between those factors and PT usage was analysed. Then, after selecting comparable studies, meta-analyses were conducted for each factor to estimate the corresponding pooled effect sizes. The meta-analysis established that car availability, teleworking opportunities and high educational level contributed the most to reducing PT use during the pandemic. These factors increased the odds of reducing PT usage compared with the pre-pandemic by about three times. Factors such as COVID-19 risk perception, gender, high income and health had a moderate effect on the decision to stop using PT. PT habits, travel distance and physical accessibility also influenced PT use during the pandemic. Geographical location and the pandemic period explained part of the heterogeneity found. The findings provided in this study can help policy-makers understand the impacts of travellers’ factors on the decision to reduce PT usage during future pandemics/epidemics and guide public policies accordingly

Anthropometric Characteristics, Body Composition and Somatotype of Elite Pan-American Race Walking 20K

The anthropometric and somatotype evaluation is an essential tool in the selection and control of high-performance athletes. The aim of this study was to describe the somatotype and body composition of male elite race walkers (20 k modality), and its relationship with athletic performance. Twenty-four race walkers participated in this study. The sample was divided into two groups: the race walkers with the best performance (upper 25 percentile; n=7) and the second group (n=17) that corresponds to the rest of the participants. Weight (kg), height (cm), seven skinfolds, two diameters and five perimeters were measured. Body fat percentage (BF%) were estimated with the Yuhasz formula, and the somatotype was used applying the Heath-Carter method. The best performing athletes were taller (178.3 +/- 4.4 cm vs. 173.7 +/- 5.6 cm, p<0.05) and showed a greater ectomorphic component (p<0.05) than the rest of the participants. The somatotype of the best performance athletes was 2.2-2.8-4.1 against the 2.5-3.8-2.9 of the lowest performing athletes. The average time (hours, minute, seconds) of execution of the race in athletes of better performances was 1: 22:40, in comparison with the athletes of lower performances with 1: 32: 41 (p<0.02). The ectomorphic component and height are morphological characteristics that can determine athletic performance of race walkers. It is suggested to consider these factors in the selection of the race walkers. La evaluación antropométrica y del somatotipo es una importante herramienta en la selección y control de los atletas de alto rendimiento. El objetivo de este estudio fue describir el somatotipo y composición corporal de hombres marchistas olímpicos, modalidad 20 k, y su relación con el rendimiento atlético. Veinticuatro atletas de marcha participaron en este estudio. La muestra fue dividida en dos grupos: los marchistas de mejores rendimientos p25 superior (n=7) y el segundo grupo (n=17) que corresponde al resto de los participantes. Se registró el peso (kg), talla (cm), siete pliegues cutáneos, dos diámetros y cinco perímetros. Se estimó el porcentaje de grasa corporal (%GC) con la fórmula de Yuhasz y se describió el somatotipo utilizando el método de Heath-Carter. Se reporta una mayor altura en los atletas de mejor rendimiento (178,3±4,4 cm vs. 173,7±5,6 cm; p<0,05) y mayor componente ectomorfico (p<0,05) que el resto de los participantes. El somatotipo de los atletas de mejor rendimiento fue de 2.2-2.8-4.1 frente al 2.5-3.8-2.9 de los atletas de menor rendimiento. El tiempo promedio (hora, minuto, segundo) de ejecución de la carrera en atletas de mejores rendimientos fue de 1:22:40, en comparación con los atletas de menores rendimientos con 1:32:41 (p <0,02). El componente ectomórfico y altura serian características morfológicas que pueden determinar el rendimiento deportivo de atletas de marcha. Se sugiere considerar estos factores en la selección de los marchistas olímpicos

The contribution of Teacher education to universities:a case study for international teacher educators

This paper reports on the initial stage of a research project which aims to develop deeper understanding of the contribution teacher education, as a sub-discipline within Education, makes to Higher Education in England. The study is located in the intersection between the domains of teacher education and higher education scholarship, which in England represents a contested and ambiguous professional space. Tensions between competing accountability measures, pulling away from university-based to exclusively school-based teacher education, are exacerbated by proposed policy changes arising from the government's recent market review. Findings drawn from analysis of qualitative data from a national survey are discussed in the context of Elizabeth Povinelli's critique of late liberalism and previous scholarship on the nature of teacher educators’ work. Evidence from the study demonstrates numerous benefits to higher education of hosting teacher education departments, including contributions to standard metrics, regional development and knowledge exchange within a strategic social justice agenda. However, teacher educators themselves may find articulating these benefits difficult, because of marginalisation from the dominant ways of achieving and accounting for excellence in the modern university. These findings offer a cautionary tale to international colleagues whose governments may be embarking on equivalent paths of teacher education reform.<br/

Laboratory Tests to Assess Optimal Agricultural Residue Traits for an Abrasive Weed Control System

International Conference of Agricultural Engineering Aarhus, Denmark 26 - 29 June (2016)One of the biggest challenges to organic agricultural production and herbicide resistant crops in industrialized countries today is the non-chemical control of weed plants. Studies of new tools and methods for weed control have been motivated by an increased consumer demand for organic produce and consumer and regulatory demands for a reduction in environmentally harmful herbicide use. The objective of this study is to assess different agricultural residues as gritty weed-abrading materials that are delivered through condensed-air machinery. This is a new weed control technology based on highly-directed air-propelled, innocuous, abrasive grit. Laboratory equipment was designed to calculate the angle of repose of seven different agricultural residues (crushed olive seed, walnut shell, maize cob, poultry manure, soybean seed, almond shell and grape seed). Color, digital, high-speed computer vision analysis of the motion and energy of the air-propelled particles was conducted. The high-speed video analysis determined the capability of each grit to damage a reference surface and kill weeds (species of Amaranthus, Centaurea, and Chenopodium) at different growth stages. A preliminary laboratory trial showed that walnut shell grit has great potential to damage/break the reference surface when it was propelled at 600, 700 and 800 kPa air pressure. Abrasive-weeding reduced final weed biomass by 80% compared with the weedy control at early growth stages. Field research tests are needed in different cropping systems to improve the technical and economic efficiency of this novel system before on-farm adoption

Foundation of Fractional Langevin Equation: Harmonization of a Many Body Problem

In this study we derive a single-particle equation of motion, from first-principles, starting out with a microscopic description of a tracer particle in a one-dimensional many-particle system with a general two-body interaction potential. Using a new harmonization technique, we show that the resulting dynamical equation belongs to the class of fractional Langevin equations, a stochastic framework which has been proposed in a large body of works as a means of describing anomalous dynamics. Our work sheds light on the fundamental assumptions of these phenomenological models.Comment: 8 pages, 2 figures, REVTeX, revised with 4 appendices added, to appear in Physical Review E

A mid-infrared Mueller ellipsometer with pseudo-achromatic optical elements

The purpose of this article is to present a new broadband Mueller ellipsometer designed to work in the mid-infrared range, from 3 to 14 microns. The Mueller ellipsometer, which can be mounted in reflection or in transmission configuration, consists of a polarization state generator (PSG), a sample holder, and a polarization state analyzer (PSA). The PSG consists in one linear polarizer and a retarder sequentially rotated to generate a set of four optimal polarization states. The retarder consists in a bi-prism made of two identical Fresnel rhombs disposed symmetrically and joined by optical contact, giving the ensemble a "V" shape. Retardation is induced by the four total internal reflections that the beam undergoes when it propagates through the bi-prism. Total internal reflection allows to generate a quasi-achromatic retardation. The PSA is identical to the PSG, but with its optical elements mounted in reverse order. After a measurement run, the instrument yields a set of sixteen independent values, which is the minimum amount of data required to calculate the Mueller matrix of the sample. The design of the Mueller ellipsometer is based on the optimization of an objective criterion that allows minimizing the propagation of errors from raw data to the Mueller matrix of the sample. The pseudo-achromatic optical elements ensure a homogeneous quality of the measurements for all wavelengths. The performance of the Mueller ellipsometer in terms of precision, and accuracy, is discussed and illustrated with a few examples

Ensemble of global climate simulations for temperature in historical, 1.5 °C and 2.0 °C scenarios from HadAM4

Large ensembles of global temperature are provided for three climate scenarios: historical (2006–16), 1.5 °C and 2.0 °C above pre-industrial levels. Each scenario has 700 members (70 simulations per year for ten years) of 6-hourly mean temperatures at a resolution of 0.833° ´ 0.556° (longitude ´ latitude) over the land surface. The data was generated using the climateprediction.net (CPDN) climate simulation environment, to run HadAM4 Atmosphere-only General Circulation Model (AGCM) from the UK Met Office Hadley Centre. Biases in simulated temperature were identified and corrected using quantile mapping with reference temperature data from ERA5. The data is stored within the UK Natural and Environmental Research Council Centre for Environmental Data Analysis repository as NetCDF V4 files