La incidencia de factores regionales y locales en el crecimiento urbano de Chillán

En este trabajo se examinan los factores regionales y locales que explican el desarrollo urbano de Chillán en las últimas 5 décadas. Se identifican los patrones del crecimiento urbano de Chillán y se cuantifican los cambios en la superficie urbana construida en un período de 57 años. Entre 1997 y el año 2000, se analizó el cambio en relación con el uso del suelo, la densidad de población y la condición socioeconómica de los hogares, con la utilización de fotografías aéreas, SIG (Arcview 3.2 y Arc-Info N.T) e índices de análisis espacial (Calculation of spatially explicit landscape index)

Evaluación multicriterio/multiobjetivo aplicada a los usos y coberturas de suelo en la cuenca de Chillán

La integración de las técnicas de Evaluación Multicriterio (EMC) y Evaluación Multiobjetivo (EMO) con los Sistemas de Información Geográfica (SIG) y programas de procesamiento de imágenes, todos ellos incluidos en el concepto amplio de Geomática, constituyen una poderosa herramienta para determinar la aptitud del territorio para ciertas actividades y usos/coberturas del suelo que requieren condiciones específicas para su expansión o consolidación en el paisaje y con ello generar lineamientos para un ordenamiento territorial efectivo. El objetivo de esta comunicación es realizar una EMC/EMO para los usos/coberturas de  la cuenca del río Chillán, ubicada en la VIII Región del Biobío, con el fin de determinar los espacios más aptos para cuatro usos representativos: espacios de conservación, plantaciones forestales, usos agrícolas y áreas de expansión urbana. De un punto de   vista metodológico se procesaron y analizaron imágenes satelitales Landsat, Aster y diversas coberturas complementarias, y posteriormente se ejecutó un modelo de EMC/EMO. Los resultados obtenidos permiten prever ciertos conflictos entre los suelos de alta  prioridad agrícola con la presión inmobiliaria futura de la ciudad de Chillán; y en los espacios cordilleranos entre las plantaciones forestales y el bosque nativo. Estos resultados pueden ser de gran ayuda para una planificación sustentable de cuencas y  planes regionales de ordenamiento territorial

The past, present, and future of accessible tourism research: A bibliometric analysis using the Scopus database

At present, it is estimated that there are more than 1 billion people with some type of disability worldwide. Against this background, it is important to reconceive every life sphere and activity to ensure the inclusion, participation and equal opportunity of people with disabilities and to promote respect for their capacities and desires as people. The tourism sector is leaving large segments of global society behind. Tourism companies need more training and guidance to address the requirements of tourists who have specific needs or require certain types of support. This study aims to analyze and map the progress in scientific research on accessible tourism. To achievethis objective, this paper presents a bibliometric analysis of scientific paperson accessible tourism published in the Scopus database between 1997 and 2021. The study used the VOSviewer and CiteSpace software to map and visualize publication trends within this field. A total of 254 articles were included, of which 95.6% were original research. These studies were published in 52 countries. Australia is among the countries with high researchproductivity in this field. The most productive journals are Tourism Management and Sustainability (Switzerland), and the most prominent author is Simon Darcy. The analysis of keywords allows us to continually review the opportunities that new information and communication technologies(specifically smartphones and virtual reality) offer for the future development of the accessible tourism sector.Peer Reviewe

El Teletrabajo un Análisis Bibliométrico a su Produción Científica

The article aims to present the development of the existing scientific literature on teleworking and identify whether Covid-19 has had an impact on scientific production in the Scopus and Web of Science databases. The methodology used to develop this research is based on a bibliometric study between the period from 1977 to October 29, 2020, in which a total of 1667 documents were reviewed through the Bibliometrix and VOSviewer software, including articles, book chapters and books. The analysis that was performed on the documents was at the level of authors, sources, documents, and keywords through the number of documents, citations, H-index, Bradford's law, Lotka, in addition to co-citation and co-authorship networks. Ultimately, scientific production has increased little by little over the years, however, Covid-19 caused this production to increase considerably. Most of the documents written on the subject are produced in collaboration and originate mostly in the United States and the United Kingdom, with Latin American countries lagging far behind in the production of teleworking documents.El artículo tiene como objetivo presentar el desarrollo de la literatura científica existente del teletrabajo e identificar si el Covid-19 ha tenido un impacto en la producción científica en las bases de datos Scopus y Web of Science. La metodología empleada para desarrollar esta investigación se basa en un estudio bibliométrico entre el período de 1977 al 29 de octubre del 2020, en el cual a través de los softwares Bibliometrix y VOSviewer se revisaron en total 1667 documentos, incluyendo artículos, capítulos de libros y libros. El análisis que se realizó a los documentos fue a nivel de autores, fuentes, documentos y palabras claves a través de la cantidad de documentos, citas, índice H, Ley de Bradford, Ley de Lotka y además de redes de co-citación y co-autoría. En definitiva, la producción científica ha crecido poco a poco con el paso de los años, sin embargo, el Covid-19 hizo que esta producción aumentara de forma considerable. La mayor parte de los documentos escritos sobre el tema se realizan en colaboración y la mayoría se originan en Estados Unidos y Reino Unido, quedando los países latinoamericanos muy rezagados en la producción de documentos del teletrabajo

Along urbanization sprawl, exotic plants distort native bee (Hymenoptera: Apoidea) assemblages in high elevation Andes ecosystem

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

Variación en la intensidad de la isla de calor urbana por efecto del cambio climático en ciudades chilenas

Urban Heat Island (UHI) is the main characteristic of the urban climate and is defined as the difference between urban and rural temperature. Its existence is explained by the design and construction materials of the city, impermeable and non-evapo-transpiring surfaces, its effects are of various kinds. The magnitude and intensity of the ICU depends on the size of the city and therefore, the volume of spatially concentrated population. The objective of this research is to propose a methodology that allows estimating the maximum intensity present and future ICU through an approximation of multiple models (climate and land use) and considering the effects of climate change. The results show that the average ICU of the main Chilean cities analyzed is consistent with values from international studies, highlighting the case of Great Santiago, which would have a UCI higher than 10 ºC.La Isla de Calor Urbano (ICU) es la principal característica del clima urbano y se define como la diferencia entre la temperatura urbana y la temperatura rural. Su existencia se explica por el diseño y materiales de construcción de la ciudad, superficies impermeables y no evapotranspirantes, y sus efectos son de diversa índole. La magnitud e intensidad de la ICU depende, a su vez, del tamaño de la ciudad y por ello, del volumen de población concentrada espacialmente. El objetivo de esta investigación es proponer una metodología que permita estimar la intensidad máxima de la ICU presente y futura mediante una aproximación de múltiples modelos (climáticos y de usos de suelo) y considerando los efectos del cambio climático. Los resultados demuestran que la ICU promedio de las principales ciudades chilenas analizadas es consistente con valores de estudios internacionales, destacando el caso del Gran Santiago que llegaría a tener una ICU mayor 10 ºC

The effects of interset rest on adaptation to 7 weeks of explosive training in young soccer players

The aim of the study was to compare the effects of plyometric training using 30, 60, or 120 s of rest between sets on explosive adaptations in young soccer players. Four groups of athletes (age 10.4 ± 2.3 y; soccer experience 3.3 ± 1.5 y) were randomly formed: control (CG; n = 15), plyometric training with 30 s (G30; n = 13), 60 s (G60; n = 14), and 120 s (G120; n = 12) of rest between training sets. Before and after intervention players were measured in jump ability, 20-m sprint time, change of direction speed (CODS), and kicking performance. The training program was applied during 7 weeks, 2 sessions per week, for a total of 840 jumps. After intervention the G30, G60 and G120 groups showed a significant (p = 0.0001 – 0.04) and small to moderate effect size (ES) improvement in the countermovement jump (ES = 0.49; 0.58; 0.55), 20 cm drop jump reactive strength index (ES = 0.81; 0.89; 0.86), CODS (ES = -1.03; -0.87; -1.04), and kicking performance (ES = 0.39; 0.49; 0.43), with no differences between treatments. The study shows that 30, 60, and 120 s of rest between sets ensure similar significant and small to moderate ES improvement in jump, CODS, and kicking performance during high-intensity short-term explosive training in young male soccer players

Vestibular dysfunction and its association with cognitive impairment and dementia

The vestibular system plays an important role in maintaining balance and posture. It also contributes to vertical perception, body awareness and spatial navigation. In addition to its sensory function, the vestibular system has direct connections to key areas responsible for higher cognitive functions, such as the prefrontal cortex, insula and hippocampus. Several studies have reported that vestibular dysfunction, in particular bilateral vestibulopathy, is associated with an increased risk of cognitive impairment and the development of dementias such as Alzheimer’s disease. However, it is still controversial whether there is a causal relationship between vestibular damage and cognitive dysfunction. In this mini-review, we will explore the relationship between the vestibular system, cognitive dysfunction and dementia, hypotheses about the hypothesis and causes that may explain this phenomenon and also some potential confounders that may also lead to cognitive impairment. We will also review multimodal neuroimaging approaches that have investigated structural and functional effects on the cortico-vestibular network and finally, describe some approaches to the management of patients with vestibular damage who have shown some cognitive impairment

Redes sociales e identidad cultural: Análisis de su incidencia en adolescentes de Ecuador

The use of social networks in the new generations has generated that the behavior of adolescents has been influenced by customs far removed from their own culture, thus losing their identity. For this reason, in the present study we proceeded to analyze of this aspect in the first-year high school students at the Octavio Cordero Palacios school in the city of Cuenca-Ecuador. The quantitative, non-experimental, cross-sectional study used the survey as an instrument for collecting information from the twenty-eight participating students. The results showed that adolescents make frequent use of social networks, where Facebook and WhatsApp platforms were the most used, which exert an important influence on changes in the behavior of those investigated, distancing them from their own cultural identity. Given this, a didactic guide for the promotion of local culture is proposed.El uso de las redes sociales en las nuevas generaciones ha generado que las conductas de los adolescentes hayan sido influenciadas por costumbres alejadas a la cultura propia, perdiendo de esta forma su identidad, Por tal motivo, en el presente estudio se procedió al análisis de este aspecto en los estudiantes de primer año de bachillerato del colegio Octavio Cordero Palacios de la ciudad de Cuenca-Ecuador. El estudio cuantitativo, no experimental, de corte transversal utilizó la encuesta como instrumento para la recolección de información de los 28 estudiantes participantes. Los resultados demostraron que los adolescentes realizan un uso frecuente de las redes sociales, donde las plataformas de Facebook y WhatsApp resultaron las más utilizadas, las cuales ejercen una importante influencia en los cambios de comportamiento de los investigados, alejándoles de su propia identidad cultural. Ante ello se propone una guía didáctica para la promoción de la cultura local