Adolescents’ perceptions of long-term effects of cycle skilltraining

Cycling to school is uncommon among adolescents in most developed countries. Development of cycling skills through cycle skills training (CST) can reduce cycling-related safety concerns. This study examined long-term effects of CST retrospectively by comparing adolescents’ perceptions of cycling to school and their confidence to cycle to school among those who participated in CST in primary and/or intermediate school with non-participants. Adolescents (n=1,260; 51% female; 12 schools) from Dunedin (New Zealand) completed an online survey at school. Adolescents self-reported transport modes to school, perceptions of cycling to school and CST, and previous participation in and perceived benefits of school-based CST programmes. Only 1-2% adolescents usually cycled to school. Overall, 42% agreed CST would make them safer in traffic (no significant difference between CST participants (n=512) and non-participants (n=748)). Among CST participants, 32% reported that CST increased their confidence to cycle to school and those adolescents had more favourable attitudes towards CST than participants who reported no effects. In a multivariable analysis, adolescents’ perceptions that CST increased their cycling confidence were positively associated with self-efficacy for cycling to school (odds ratio (OR) (95% confidence interval (CI)): 1.33 (1.07, 1.67)), perceived school support (1.51 (1.01, 2.25)), parental cycling-related safety concerns (1.84 (1.25, 2.69)) and being Māori (6.47 (2.36, 17.7)) or other ethnic origins (2.26 (1.00, 5.10); reference: New Zealand Europeans). Therefore, CST could be a useful strategy to support adolescents’ cycling to school, ideally (as suggested in the literature) in combination with appropriate infrastructure changes and speed management measures

Gender differences in perceived environmental correlates of physical activity

BACKGROUND: Limited research has been conducted on gender differences in perceived environmental correlates of physical activity (PA). The purpose of this study was to explore the potential role of gender in the link between perceived environment and PA. METHODS: Using a telephone-administered survey, data was collected on leisure time physical activity (LTPA), perceptions of the neighbourhood environment, and self-efficacy in a representative sample of 1209 adults from the province of Alberta, Canada. LTPA was regressed on ten measures of perceived neighbourhood environment and self-efficacy in a series of logistic regressions. RESULTS: Women were more likely than men to perceive their neighbourhood as unsafe to go for walks at night (χ(2 )= 67.46, p < 0.001) and to report seeing people being active in their neighbourhood (χ(2 )= 6.73, p < 0.01). Conversely, women were less likely to perceive easy access to places for PA (χ(2 )= 11.50, p < 0.01) and availability of places to buy things within easy walking distance from home (χ(2 )= 4.30, p < 0.05). Adjusting for age, education, income, and place of residence, access to places for PA (OR = 2.49) and interesting things to look at in the neighbourhood (OR = 1.94), were associated with higher levels of LTPA in men. Access to places for PA (OR = 2.63) and reporting seeing people being active (OR = 1.50) were associated with increased LTPA among women. After controlling for sociodemographic variables and self-efficacy, the presence of shops and places to buy things within easy walking distance from home (OR = 1.73), interesting things to look at in the neighbourhood (OR = 1.65), and access to places for PA (OR = 1.82) were associated with higher levels of LTPA in men. Among women, no significant relationships were observed between perceived environment and LTPA after adjusting for self-efficacy. CONCLUSION: The results provide additional support for the use of models in which gender is treated as a potential moderator of the link between the perceived environment and PA. Further, the results suggest the possibility of differential interventions to increase PA based on factors associated with gender

Comportamiento dinámico de puentes en arco con amortiguadores viscosos

En éste trabajo se presenta la respuesta sísmica analítica de dos puentes en arco de gran luz, sometiéndolos a un movimiento simulado que incluye efectos de fuente cercana. Para reducir la respuesta se exploró su comportamiento conectando los dos extremos del tablero con la subestructura por medio de amortiguadores viscosos. Se llevaron a cabo una serie de análisis en el plano de ambos modelos para identificar los amortiguadores óptimos. Los resultados indicaron que el uso de amortiguadores viscosos con comportamiento no lineal, ofrece una solución práctica para reducir la respuesta dinámica de estas estructuras

Insights into the nature of the active sites of pt-wox/al2o3 catalysts for glycerol hydrogenolysis into 1, 3-propanediol

The chemo-selective hydrogenolysis of secondary hydroxyls is an important reaction for the production of biomass-derived a, ¿-diols. This is the case for 1, 3-propanediol production from glycerol. Supported Pt-WOx materials are effective catalysts for this transformation, and their activity is often related to the tungsten surface density and Brönsted acidity, although there are discrepancies in this regard. In this work, a series of Pt-WOx/¿-Al2O3 catalysts were prepared by modifying the pH of the solutions used in the active metal impregnation step. The activity–structure relation-ships, together with the results from the addition of in situ titrants, i.e., 2, 6-di-tert-butyl-pyridine or pyridine, helped in elucidating the nature of the bifunctional active sites for the selective production of 1, 3-propanediol. © 2021 by the authors. Licensee MDPI, Basel, Switzerland

3D reconstruction of weeds using depth cameras

El objetivo de este estudio fue optimizar el ángulo de posicionamiento del sensor Kinect para la reconstrucción de la estructura tridimensional de Xanthium strumarium L., Datura stramonium L. y Chenopodium album L., utilizando para ello algoritmos que permiten la captura y combinación de imágenes de profundidad y RGB. Se han comparado diferentes ángulos, fijando en cada uno de ellos el sensor Kinect de forma estática respecto de la planta objetivo. Los resultados han confirmado la correlación entre la biomasa de malas hierbas y el área estimada con el sensor. La estimación de la altura de las plantas también fue adecuada, con una media de 2cm de error dependiendo de la posición del sensor. Sin embargo, aunque el sensor ha mostrado su capacidad para la creación de modelos tridimensionales, el adecuado posicionamiento del sensor es fundamental para la correcta reconstrucción de plantas. La posición ideal del sensor debe ser elegida de acuerdo a la especie a medir y su estado fenológico. Estos resultados sugieren que Kinect es una herramienta útil para caracterizar de forma rápida y fiable las malas hierbas, con importantes ventajas sobre otros sensores debido a su bajo coste, bajo requerimiento energético y alta frecuencia de transmisión de imágenes.The objective of this study was to optimize the positioning angle of a Kinect sensor for reconstructing the three dimensional structure of weeds, using Kinect fusion algorithms to generate a 3D point cloud from the depth video stream. The sensor was mounted in different positions facing the plant in order to obtain depth (RGB-D) images from different angles. The results confirmed the correlation between ground truth (e. g. weed biomass) and the measured area with Kinect. In addition, plant height was accurately estimated with a few centimeters error. However, although the Kinect sensor has shown its ability for plant reconstruction, proper positioning of the sensor is critical for correct reconstruction of plants. The best position of the sensor must be chosen according to the species to be measured and their growth stage. These results suggest that Kinect is a promising tool for a rapid and reliable weed characterization, with several important advantages such as low cost, low power requirement and a high frame rate

Twitter, partisan use and institutional use: Comparative analysis between the profiles of Moncloa, Madrid City Council and their ruling parties

This paper seeks to compare and analyse the differences in the use of Twitter that, Partido Popular, as a traditional political party, and Ahora Madrid, as a new political party, make of the institutional channels for the public institutions that they administer. In addition, the present study analyses three different periods in the electoral process: the pre-campaign, campaign and post-campaign during the Spanish general elections of December 20th, 2015 in order to see if the election periods caused changes in their communications on Twitter. The sample consists of four cases divided into two groups for content analysis. On one hand, the Government’s Twitter profile (@desdelamoncloa) and of its ruling party, Partido Popular (@ppopular), comprise the old political group, while the Madrid City Council (@Madrid) and its ruling party, Ahora Madrid (@AhoraMadrid), are integrated into the new political group. Additionally, word clouds provide a visual representation of the main terms used by each group. The study results show which group uses and better leverages Twitter’s potential, in that Partido Popular and Moncloa have clearer differences between party and institutional channels, while Ahora Madrid and the Madrid City Council do not seem to be as clear about the difference between the two concepts and use the party channel as the city council channel. However, the results demonstrate that the new political profile leverages Twitter’s potential more.El presente trabajo analiza las diferencias de uso de Twitter por parte de dos partidos políticos españoles, Partido Popular, como partido tradicional, y Ahora Madrid, como nuevo partido, así como la utilización de los canales institucionales de los entes públicos que estos partidos presiden a nivel nacional y local, respectivamente. Los resultados muestran usos y aprovechamientos diferentes de las potencialidades de Twitter. El estudio se realizó en tres periodos electorales diferenciados: precampaña, campaña y post-campaña de las elecciones generales del 20 de diciembre de 2015, para examinar también cambios de comportamiento en la comunicación en Twitter en el periodo electoral. La muestra consta de cuatro casos divididos en dos grupos para el análisis de contenido. Por un lado, el perfil en Twitter del Gobierno (@desdelamoncloa) y el del partido gobernante, el Partido Popular (@ppopular) constituyen el grupo de la vieja política. Por otro lado, el Ayuntamiento de Madrid (@madrid) y su partido gobernante, Ahora Madrid (@AhoraMadrid), se integran dentro del grupo de nueva política. Además, unas nubes de palabras presentarán visualmente las principales ideas enviadas por los perfiles. Los resultados indican que Partido Popular y Moncloa mantuvieron un uso diferenciado entre los canales de partido y los institucionales, mientras que en el caso de Ahora Madrid y el Ayuntamiento de Madrid se constataron usos concluyentes y no diferenciados entre el canal del partido y el institucional. Además, se observa que los perfiles de la nueva política aprovechan más las potencialidades de Twitter

LGMDD1 natural history and phenotypic spectrum: Implications for clinical trials

OBJECTIVE: To delineate the full phenotypic spectrum and characterize the natural history of limb girdle muscular dystrophy type D1 (LGMDD1). METHODS: We extracted age at clinical events of interest contributing to LGMDD1 disease burden via a systematic literature and chart review. Manual muscle testing and quantitative dynamometry data were used to estimate annualized rates of change. We also conducted a cross-sectional observational study using previously validated patient-reported outcome assessments (ACTIVLIM, PROMIS-57) and a new LGMDD1 questionnaire. Some individuals underwent repeat ACTIVLIM and LGMDD1 questionnaire assessments at 1.5 and 2.5 years. RESULTS: A total of 122 LGMDD1 patients were included from 14 different countries. We identified two new variants (p.E54K, p.V99A). In vitro assays and segregation support their pathogenicity. The mean onset age was 29.7 years. Genotype appears to impact onset age, weakness pattern, and median time to loss of ambulation (34 years). Dysphagia was the most frequent abnormality (51.4%). Deltoids, biceps, grip, iliopsoas, and hamstrings strength decreased by (0.5-1 lb/year). Cross-sectional ACTIVLIM and LGMDD1 questionnaire scores correlated with years from disease onset. Longitudinally, only the LGMDD1 questionnaire detected significant progression at both 1.5 and 2.5 years. Treatment trials would require 62 (1.5 years) or 30 (2.5 years) patients to detect a 70% reduction in the progression of the LGMDD1 questionnaire. INTERPRETATION: This study is the largest description of LGMDD1 patients to date and highlights potential genotype-dependent differences that need to be verified prospectively. Future clinical trials will need to account for variability in these key phenotypic features when selecting outcome measures and enrolling patients

El puente con pretensado extradosado. Un nuevo tipo estructural

La idea de estos puentes y su denominación proviene de Mathivat quien, en 1988, propone comosolución de concurso del viaducto de L'Arret-DarréW1 puente con esta tipología, que se caracterizapor disponer el pretensado, sobre las secciones de apoyo en pila, exteriormente al canto de lasección y por la pane superior del tablero, intentando ganar excentricidad. Resulta, así, unaespecie de puente de tirantes con pila baja y canto holgado, que busca, además de la compensaciónde cargas, que la variación de tensión en el acero de los tendones extradosados, debida a lasobrecarga, sea lo suficientemente baja para que no se requieran los caros anclajes resistentes afatiga empleados en los puentes de tirantes. El artículo ilustra la concepción y desarrollo de este tipo de puente a partir de la evolución delconcepto de compensación de cargas mediante el pretensado con tendones de acero y de laconstrucción por avance en voladizo. Hace una presentación de los puentes construidos o enfase de construcción que pueden ser catalogados dentro de esta tipología de puentes. Además, ydado que la filosofía de diseño de este tipo de puentes busca agotar las posibilidades de laresistencia afatiga de los tendones de pretensado exterior, se presenta un resumen de la revisiónbibliográfica existente sobre fatiga en tendones y tirantes de acero y sus dispositivos de apoyo yanclaje. Por último, se establecen las principales conclusiones de la investigación.The idea of ​​these bridges and their designation comes from Mathivat who, in 1988, proposes as a solution to the L'Arret-DarréW1 viaduct bridge with this typology, which is characterized by the provision of prestressing, on the support sections in stack , Externally to the edge of the section and to the upper part of the board, trying to gain eccentricity. Thus, it is a kind of tie-rod bridge with low pile and loose edge, which seeks, besides the compensation of loads, that the variation of stress in the steel of the extrados tendons, due to the overload, is sufficiently low so that the expensive fatigue resistant anchors used in the jumpers are not required. The article illustrates the conception and development of this type of bridge from the evolution of the concept of load compensation by prestressing with steel tendons and the construction by cantilever advancement. It gives a presentation of the bridges built or under construction that can be cataloged within this type of bridge. In addition, given that the design philosophy of this type of bridges seeks to exhaust the possibilities of fatigue resistance of the external prestressing tendons, a summary of the existing literature review on fatigue in tendons and steel straps and their devices Support and anchorage. Finally, the main conclusions of the investigation are establishe