268 research outputs found

    Chemical pavement modifications to reduce ice adhesion

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    The formation of ice and snow on road pavement surfaces is a recurring problem, creating hazardous driving conditions, restricting public mobility as well as having adverse economic effects. It would be desirable to develop new and improved ways of modifying the pavement surface, to prevent or at least delay the build-up of ice and to weaken the pavement–ice bond, and making the ice which forms easier to remove. This development could lead to economic, environmental and safety benefits for winter service providers and road users. This paper describes how environmental scanning electron microscopy was used to examine the mechanism by which de-icing chemicals, added as a filler replacement to bituminous materials, can be transferred to the pavement surface. The paper assesses the potential for chemical modifications to reduce the adhesion between ice and the pavement surface by means of work of adhesion calculations, based on surface energy parameters and a new physical ice bond test. The paper also examines the influence that the chemical modifications have on the durability of the pavement surface course

    Locating the place and meaning of physical activity in the lives of young people from low-income, lone-parent families

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    Background: In the United Kingdom (UK), it is predicted that economic cuts and a subsequent increase in child poverty will affect those already on the lowest incomes and, in particular, those living in lone-parent families. As a result, the informal pedagogic encounters within the family that contribute to the development of physical activity-related values, beliefs and dispositions from a very early age will be affected. Therefore, it is vital that we gain an understanding of the place and meaning of physical activity in the lives of young people, as well as the informal pedagogic practices and the socio-cultural forces that influence individual agency. Purpose: Based on Bourdieu's key concepts, this paper explores the interplay of structural conditions and personal agency with regard to physical activity in the lives of young people from low-income, lone-parent families. Methods: This study reports on the voices of 24 participants (aged 11–14) from low-income, lone-parent families in the West Midlands, UK. These participants were engaged in paired, semi-structured interviews to explore issues of personal agency by listening to how they reported on their present lives, past experiences and future possibilities with regard to physical activity. All corresponding interview data were analysed using analytical induction. Findings: This paper suggests that young people exhibited diminished desires to engage in activity due to structural constraints of time, parents' work commitments and a lack of transport that resulted in engagement in sedentary alternatives. Informal pedagogic practices within these families were restricted due to the associated structural conditions of living in a lone-parent family. As such, young people's choice to not seek out physical activities when at home reflected a ‘taste for necessity’ resulting from a lack of cultural and economic capital, placing restrictions on physical activity opportunities that stemmed from their family doxa. Conclusions: To succeed in fostering dispositions and opportunities to participate in physical activity, we must engage with young people from low-income, lone-parent families from an early age. Certainly though, further consideration of the informal pedagogic practices within, and the demands on, lone-parent families is required when designing any intervention or policy that seeks to enhance their current circumstances and provide opportunities for engagement in a variety of contexts

    Poliéster armado con fibra de vidrio en la obra de Tous y Fargas

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    The architects Enric Tous (1925; t 1952) and Josep Maria Fargas (1926-2011, t 1952) achieved remarkable success during the 1960s and 1970s thanks to their commitment to technical experimentation and exploration of new construction systems. Among their most significant contributions is the incorporation of polyester reinforced with glass fiber as a material applied to solutions of light facades. This article tracks the origin, context, and results they obtained with this material. We propose an approach to the GRC material through the experience developed by the architects, analyzing the characteristics and specific implications of the systems proposed in their projects. Through this reading, the industrial initiative implemented by Tous and Fargas is put into value, and the key aspects that limited the progression of the construction system are detected.Los arquitectos Enric Tous (1925; t. 1952) y Josep Maria Fargas (1926-2011; t. 1952) alcanzaron un éxito notable durante las décadas de 1960 y 1970 gracias a su trabajo comprometido con la experimentación técnica y la exploración de nuevos sistemas constructivos. Entre sus aportaciones más significativas destaca la incorporación del poliéster armado con fibra de vidrio como material aplicado a soluciones de cerramientos ligeros. Este artículo rastrea el origen, contexto y resultados que obtuvieron con este material. Se propone un acercamiento al material GRC a través de la experiencia desarrollada por los arquitectos, analizando las características e implicaciones específicas de los sistemas propuestos en sus proyectos. A través de esta lectura se pone en valor la iniciativa industrial puesta en práctica por Tous y Fargas, detectándose los aspectos clave que limitaron la progresión del sistema constructivo

    Can’t pay, can’t play? Talent lead’s perspectives on the financial constraints experienced by athletes on the England Talent Pathway

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    © 2017 European Council for High Ability This study explored the extent of financial constraints experienced by athletes on the England Talent Pathway, as perceived by talent leads from various sports. Using a mixed-methods approach, 34 participants completed online surveys with 26 follow-up interviews. Findings showed the prevalence of financial constraints on individuals within the system, with three emerging themes: costs; demands on athletes; and potential funding support. “Pinch points”, causing the greatest severity of financial constraint, emerged further along the pathway and there were infrequent examples of mechanisms to identify talented athletes experiencing financial hardship. A means-tested system, premised on the demonstration of potential, is suggested by talent leads as a way of providing funding for athletes to ameliorate financial constraints in the future

    A single base mutation in the androgen receptor gene causes androgen insensitivity in the testicular feminized rat.

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    The complete form of androgen insensitivity is an inherited X-linked syndrome in which genetic males fail to undergo masculinization in utero due to defective functioning of the androgen receptor (AR). The molecular basis of androgen insensitivity was investigated in the testicular feminized (Tfm) rat with this syndrome. AR mRNA size and amount, as well as nuclear AR protein revealed by immunocytochemistry, suggested normal expression of the AR gene in the Tfm rat. Sequence analysis of the AR coding region from Tfm and wild-type littermate male rats revealed a single transition mutation, guanine to adenine, within exon E, changing arginine 734 to glutamine within the steroid-binding domain of the AR. This arginine is highly conserved among the family of nuclear receptors and may be part of a phosphorylation recognition site. A recreated mutant AR (Arg734----Gln) expressed in COS cells had only 10-15% of the androgen-binding capacity of wild-type AR; the reduced androgen-binding capacity was similar to that of AR in tissue extracts of the Tfm rat. Stimulation of transcriptional activity by the recreated mutant AR was reduced relative to wild-type AR in cotransfection assays in CV1 cells using as reporter plasmid the mouse mammary tumor virus promoter linked to the chloramphenicol acetyltransferase gene. Thus, arginine 734 appears essential for normal AR function both in androgen binding and transcriptional activation. Absence of these functions results in androgen insensitivity and lack of male sexual development
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