495 resultados para Bicycle helmet
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Background Brachial blood pressure predicts cardiovascular outcome at rest and during exercise. However, because of pulse pressure amplification, there is a marked difference between brachial pressure and central (aortic) pressure. Although central pressure is likely to have greater clinical importance, very little data exist regarding the central haemodynamic response to exercise. The aim of the present study was to determine the central and peripheral haemodynamic response to incremental aerobic exercise. Materials and methods Twelve healthy men aged 31 +/- 1 years (mean +/- SEM) exercised at 50%, 60%, 70% and 80% of their maximal heart rate (HRmax) on a bicycle ergometer. Central blood pressure and estimated aortic pulse wave velocity, assessed by timing of the reflected wave (T-R), were obtained noninvasively using pulse wave analysis. Pulse pressure amplification was defined as the ratio of peripheral to central pulse pressure and, to assess the influence of wave reflection on amplification, the ratio of peripheral pulse pressure to nonaugmented central pulse pressure (PPP : CDBP-P-1) was also calculated. Results During exercise, there was a significant, intensity-related, increase in mean arterial pressure and heart rate (P < 0.001). There was also a significant increase in pulse pressure amplification and in PPP : CDBP-P-1 (P < 0.001), but both were independent of exercise intensity. Estimated aortic pulse wave velocity increased during exercise (P < 0.001), indicating increased aortic stiffness. There was also a positive association between aortic pulse wave velocity and mean arterial pressure (r = 0.54; P < 0.001). Conclusions Exercise significantly increases pulse pressure amplification and estimated aortic stiffness.
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The issues involved in planning for pedal cyclists are examined with reference to the West Midlands County. Working with a local cycling campaign group, the researcher uses action research methods to investigate and influence the campaign. Development of cycle planning is traced through the literature, focusing on bicycle ownership, bicycle use and cycling policy. UK practice is contrasted with the integrated approach of other countries. An extensive bibliography is provided. Local authority cycle planning through the TPP process is systematically assessed over three years. This provides a context for the information regarding cycling in the West Midlands. Existing data is presented from the 1981 Census and local police road accident and bicycle theft records. The developing relationship between the local authority and the cycle campaign group is narrated in detail, explaining the problems that can beset efforts to improve conditions for cyclists. The researcher was closely involved in this interaction, particularly with policy and a major public inquiry. A survey of the Cycle Campaign Network indicates that the local group was not atypical. To provide information relevant to the local campaign and for effective local planning, a survey of 3,500 West Midlands residents was conducted using a novel combination of questionnaires and interviews. It shows that 1) Bicycle ownership and use is considerably higher than indicated by the 1978/9 National Travel Survey 2) Cycling is most import to certain disadvantaged sections of the community, particularly the young, those without access to a car and in the lower SEGs. The broader issues of transport policy are discussed, concluding that cycling is regarded as a marginal activity and that changes in general transport policy, land use planning and fiscal arrangements are necessary conditions for cycle planning to succeed. An integrated package of cycling measures involving engineering, education, enforcement and encouragement is also required. Recommendations are made concerning central government, local authorities and cycle campaign groups. Subjects for further research are identified.
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Despite years of effort in building organisational taxonomies, the potential of ontologies to support knowledge management in complex technical domains is under-exploited. The authors of this chapter present an approach to using rich domain ontologies to support sense-making tasks associated with resolving mechanical issues. Using Semantic Web technologies, the authors have built a framework and a suite of tools which support the whole semantic knowledge lifecycle. These are presented by describing the process of issue resolution for a simulated investigation concerning failure of bicycle brakes. Foci of the work have included ensuring that semantic tasks fit in with users’ everyday tasks, to achieve user acceptability and support the flexibility required by communities of practice with differing local sub-domains, tasks, and terminology.
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This paper explores how the concept of Alzheimer’s disease (AD) is constructed through Spanish media and documentary films and how it is represented. The article analyses three documentary films and the cultural and social contexts in and from which they emerged: Solé´s Bucarest: la memòria perduda [Bucharest: Memory Lost] (2007), Bosch´s Bicicleta, cullera, poma [Bicycle, Spoon, Apple] (2010) , and Frabra’s Las voces de la memoria [Memory´s Voices] (2011). The three documentary films approach AD from different perspectives, creating well-structured discourses of what AD represents for contemporary Spanish society, from medicalisation of AD to issues of personhood and citizenship. These three films are studied from an interdisciplinary perspective, in an effort to strengthen the links between ageing and dementia studies and cultural studies. Examining documentary film representations of AD from these perspectives enables semiotic analyses beyond the aesthetic perspectives of film studies, and the exploration of the articulation of knowledge and power in discourses about AD in contemporary Spain
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This paper discusses the development and the application of a safety performance indicator which measures the intrinsic safety of a country's vehicle fleet related to fleet composition. The indicator takes into account both the ‘relative severity’ of individual collisions between different vehicle types, and the share of those vehicle types within a country's fleet. The relative severity is a measure for the personal damage that can be expected from a collision between two vehicles of any type, relative to that of a collision between passenger cars. It is shown how this number can be calculated using vehicle mass only. A sensitivity analysis is performed to study the dependence of the indicator on parameter values and basic assumptions made. The indicator is easy to apply and satisfies the requirements for appropriate safety performance indicators. It was developed in such a way that it specifically scores the intrinsic safety of a fleet due to its composition, without being influenced by other factors, like helmet wearing. For the sake of simplicity, and since the required data is available throughout Europe, the indicator was applied to the relative share of three of the main vehicle types: passenger cars, heavy goods vehicles and motorcycles. Using the vehicle fleet data from 13 EU Member States and Norway, the indicator was used to rank the countries’ safety performance. The UK was found to perform best in terms of its fleet composition (value is 1.07), while Greece has the worst performance with the highest indicator value (1.41).
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Magnetoencephalography (MEG) offers significant opportunities for the localization and characterization of focal and generalized epilepsies, but its potential has so far not been fully exploited, as the evidence for its effectiveness is still anecdotal. This is particularly true for pediatric epilepsy. MEG recordings on school-age children typically rely on the use of MEG systems that were designed for adults and children's smaller head-size and stature can cause significant problems. Reduced signal-to-noise ratio when recording from smaller heads, increased movement, reduced sensor coverage of anterior temporal regions and incomplete insertion into the MEG helmet can all reduce the quality of data collected from children. We summarize these challenges and suggest some practical solutions.
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During the past three decades, the use of roundabouts has increased throughout the world due to their greater benefits in comparison with intersections controlled by traditional means. Roundabouts are often chosen because they are widely associated with low accident rates, lower construction and operating costs, and reasonable capacities and delay. ^ In the planning and design of roundabouts, special attention should be given to the movement of pedestrians and bicycles. As a result, there are several guidelines for the design of pedestrian and bicycle treatments at roundabouts that increase the safety of both pedestrians and bicyclists at existing and proposed roundabout locations. Different design guidelines have differing criteria for handling pedestrians and bicyclists at roundabout locations. Although all of the investigated guidelines provide better safety (depending on the traffic conditions at a specific location), their effects on the performance of the roundabout have not been examined yet. ^ Existing roundabout analysis software packages provide estimates of capacity and performance characteristics. This includes characteristics such as delay, queue lengths, stop rates, effects of heavy vehicles, crash frequencies, and geometric delays, as well as fuel consumption, pollutant emissions and operating costs for roundabouts. None of these software packages, however, are capable of determining the effects of various pedestrian crossing locations, nor the effect of different bicycle treatments on the performance of roundabouts. ^ The objective of this research is to develop simulation models capable of determining the effect of various pedestrian and bicycle treatments at single-lane roundabouts. To achieve this, four models were developed. The first model simulates a single-lane roundabout without bicycle and pedestrian traffic. The second model simulates a single-lane roundabout with a pedestrian crossing and mixed flow bicyclists. The third model simulates a single-lane roundabout with a combined pedestrian and bicycle crossing, while the fourth model simulates a single-lane roundabout with a pedestrian crossing and a bicycle lane at the outer perimeter of the roundabout for the bicycles. Traffic data was collected at a modern roundabout in Boca Raton, Florida. ^ The results of this effort show that installing a pedestrian crossing on the roundabout approach will have a negative impact on the entry flow, while the downstream approach will benefit from the newly created gaps by pedestrians. Also, it was concluded that a bicycle lane configuration is more beneficial for all users of the roundabout instead of the mixed flow or combined crossing. Installing the pedestrian crossing at one-car length is more beneficial for pedestrians than two- and three-car lengths. Finally, it was concluded that the effect of the pedestrian crossing on the vehicle queues diminishes as the distance between the crossing and the roundabout increases. ^
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The expansion of the specialty of sports and exercise medicine (SEM) is a relatively recent development in the medical community and the role of the SEM specialist continues to evolve and develop. The SEM specialist is ideally placed to care for all aspects of physical activity not only in athletes but also in the general population. As an advocate for physical activity the SEM specialist plays a broad role in advising safe effective sports and recreation participation; screening for disease related to sports participation; examining and contributing to the evidence behind treatment strategies and evaluating any potential negative impact of sports injury prevention measures. In this thesis I will demonstrate the breadth of the role the Sports and Exercise Medicine Specialist from epidemiology to in-depth examination of treatment strategies. In Chapter 2, I examined the epidemiology of sports and recreation related injury (SRI) in Ireland, an area that has previously been poorly studied. We report on 3,172 SRI (14% of total presentations) presentations to the ED over 6 months. Paediatric patients (4-16 yrs) were over represented comprising 39.9% of all SRI presentation compared to 16% of total ED presentations and 18% of the general population. These injuries were serious (32% fractures) and though 49% of injuries occurred during organised competition/practice, 41.5% occurred during recreation-most often at home. In Chapter 3, I examined risk factors associated with hand injury in hurling. The previous chapter highlighted the importance of a firm evidence base underpinning treatment strategies. When measures to improve welfare are introduced not only must potential benefits be measured, so too must potential unwanted adverse outcomes. In this study I examined a cohort of adult hurlers who had presented to the ED with a hurling related injury in order to highlight the variables associated with hand injury in this population. I found the athletes who wore a helmet were far more likely (OR 3.15 95% CI (1.51-6.56) p= 0.002) to suffer a hand injury than athletes who did not. Very few of those interviewed (4.9%) used hand protection compared to 65% who used helmet and faceguard. The introduction of the helmet and faceguard in hurling has undeniably decreased the incidence of head and face injury in hurling. However in tandem with this intervention several observational studies have demonstrated an increase in the occurrence of hurling related hand injuries. This study highlights the importance of being cognisant of unanticipated or unintended consequences when implementing a new treatment or intervention. In Chapter 4, I examined the role of population screening as applied to sport and exercise. This is a controversial area –cardiac screening in the exercising population has been the subject of much debate. Specifically I define the prevalence of exercise induced bronchoconstriction (EIB) using a specifically designed sports specific field-testing protocol. In this study I found almost a third (29%) of a full international professional rugby squad had confirmed asthma or EIB, as compared with 12-15% of the general population. Despite regular medical screening, 5 ‘new’ untreated cases (12%) were elicited by the challenge test and in the group already on treatment for asthma/EIB; over 50% still displayed EIB. In Chapter 5, I examined the evidence supporting current treatment options for iliotibial band friction syndrome (ITBFS). The practice of sports medicine has traditionally been ‘eminence based’ rather than ‘evidence based’. This may be problematic as some of these practices are based upon flawed principles- for example the treatment of iliotibial band friction syndrome (ITBFS). In this chapter, using cadaveric and biomechanical studies I expand upon the growing base of evidence clarifying the anatomy and biomechanics of the area-thereby re-examining the principles on which current treatments are based. The role of the SEM specialist is broad; we chose to examine specific examples of some of the roles that they execute. An understanding of the epidemiology of SRI presenting to the ED has implications for individual patients, sports governing bodies and health resource utilisation. Population screening is an important tool in health promotion and disease prevention in the general population. Screening in SEM may have similar less well-recognised benefits. The SEM specialist needs to be conversant in screening for medical conditions concerning physical activity. A comprehensive understanding of the pathophysiology of a disease is required for its diagnosis and treatment. Due to the ongoing evolution of SEM many treatments are eminence-based rather than evidence‐based practice. Continued re-examination of the fundamentals of current practice is essential. An awareness of potential unwanted side effects is essential prior to the introduction of any new treatment or intervention. The SEM specialist is ideally placed to advise sports governing bodies on these issues prior to and during their implementation.
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Many engineers currently in professional practice will have gained a degree level qualification which involved studying a curriculum heavy with mathematics and engineering science. While this knowledge is vital to the engineering design process so also is manufacturing knowledge, if the resulting designs are to be both technically and commercially viable.
The methodology advanced by the CDIO Initiative aims to improve engineering education by teaching in the context of Conceiving, Designing, Implementing and Operating products, processes or systems. A key element of this approach is the use of Design-Built-Test (DBT) projects as the core of an integrated curriculum. This approach facilitates the development of professional skills as well as the application of technical knowledge and skills developed in other parts of the degree programme. This approach also changes the role of lecturer to that of facilitator / coach in an active learning environment in which students gain concrete experiences that support their development.
The case study herein describes Mechanical Engineering undergraduate student involvement in the manufacture and assembly of concept and functional prototypes of a folding bicycle.
Resumo:
BACKGROUND:
Evidence regarding the association of the built environment with physical activity is influencing policy recommendations that advocate changing the built environment to increase population-level physical activity. However, to date there has been no rigorous appraisal of the quality of the evidence on the effects of changing the built environment. The aim of this review was to conduct a thorough quantitative appraisal of the risk of bias present in those natural experiments with the strongest experimental designs for assessing the causal effects of the built environment on physical activity.
METHODS:
Eligible studies had to evaluate the effects of changing the built environment on physical activity, include at least one measurement before and one measurement of physical activity after changes in the environment, and have at least one intervention site and non-intervention comparison site. Given the large number of systematic reviews in this area, studies were identified from three exemplar systematic reviews; these were published in the past five years and were selected to provide a range of different built environment interventions. The risk of bias in these studies was analysed using the Cochrane Risk of Bias Assessment Tool: for Non-Randomized Studies of Interventions (ACROBAT-NRSI).
RESULTS:
Twelve eligible natural experiments were identified. Risk of bias assessments were conducted for each physical activity outcome from all studies, resulting in a total of fifteen outcomes being analysed. Intervention sites included parks, urban greenways/trails, bicycle lanes, paths, vacant lots, and a senior citizen's centre. All outcomes had an overall critical (n = 12) or serious (n = 3) risk of bias. Domains with the highest risk of bias were confounding (due to inadequate control sites and poor control of confounding variables), measurement of outcomes, and selection of the reported result.
CONCLUSIONS:
The present review focused on the strongest natural experiments conducted to date. Given this, the failure of existing studies to adequately control for potential sources of bias highlights the need for more rigorous research to underpin policy recommendations for changing the built environment to increase physical activity. Suggestions are proposed for how future natural experiments in this area can be improved.
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Thesis (Master's)--University of Washington, 2016-06
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Despite the high incidence of abdominal traumas, traumatic abdominal wall hernias (TAWHs) remain rare probably because of elasticity of the abdominal wall. The TAWH is due to blunt abdominal trauma with disruption of the abdominal wall muscles and fascia with intact overlying skin. TAWH can be classified into high energy injures (generally motor vehicle accidents) and low energy injures (impact on a small blunt object). Common example of the latter type is a fall onto a bicycle handlebar. The mechanism of the trauma includes sudden increase of intra-abdominal pressure and extensive shear forces applied to the abdominal wall. The diagnosis of TAWH is difficult in the Emergency Room because during the primary diagnostic process most attention is directed toward the detection of internal injures and TAWH can be missed. In this article we report a case of TAWH caused by a work accident (an heavy steel tube fallen onto the abdominal wall of the patient from a height of five meters) with delayed diagnosis.
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The urban mobility has in the bicycle its symbol of the most environmentally sustainable modal of transportation of the planet, title conferred by the United Nations Organization (ONU). Nevertheless, the cities suffer with the traffic jam caused by the automobile fleet growth, what implies in a larger displacement time, injuries to the environment, to financials and to the quality of life. In order to build in a sustainable way the urban mobility, public policies are necessary to encourage the preferential usage, by the society, of the mass transit or the non-motorized type of transportation. Objecting cooperate with the public power and the civil society, this study intents to, through an analysis about the UFPR Extension Program - CICLOVIDA, propose a sustainable urban mobility public policy development, with emphasis in the bicycle´s usage. eferentially, it is discussed concepts such as Society, State and Government as well as public policies, which go in cycles to the State´s and Government´s responsibilities; and are presented the Sustainable Urban Mobility Public Policies (PPMUS) in Brazil. Also, it is debated about the transport by bicycle as an option to the sustainable mobility. Methodologically, the study is of an empiric-social nature, with the application of both qualitative and observational methods, what characterizes as an exploratory level of research, with the researcher´s involvement in the participant form, due to her acting on the Program. Regarding the research lineation, it was used the bibliographic and documental form as well as case study, by means of the nonparametric sampling by accessibility or convenience. Related to the data collection technique, it was used structured interviews with self-applied questionnaires and natural participant observation. Aligned with the research´s objective and matter, the outcome confirmed that the Extension Program CICLOVIDA of the Federal University of Paraná (UFPR) may effectively contribute in the development of a PPMUS proposal with emphasis in the bicycle usage. Thus, it was built a political proposal with a free form writing, objecting subsidize policies both institutional as public MUS through the bicycle usage and therefore, support the mobility, also contributing to the sustainability and to the public development planning.
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Com uma Sociedade cada vez mais complexa e evolutiva, vários são os desafios a que somos postos à prova. Com isto, a população apesar das suas dependências e comodismos, tende a procurar novos meios de lazer que se envolvam com a natureza e com a prática desportiva. Deste modo, o Cicloturismo vai ao encontro destas práticas, tornando-se um mercado em evolução, cuja a aderência do número de pessoas tem vindo a crescer, sendo um tipo de turismo que acarreta resultados positivos, tais como um estilo de vida saudável, bem como a utilização de um meio de transporte de baixo custo e com uma pegada ecológica. Na mesma linha de pensamento, o presente documento aborda todo o processo de execução de um Quadriciclo. O objetivo geral do mesmo, incide em satisfazer as necessidades dos praticantes de cicloturismo e incentivar as pessoas para o uso da bicicleta como meio de transporte. Para tal, os participantes envolvidos foram utilizadores assíduos do uso da bicicleta, não só procurando-a para o lazer, mas sim para a prática do Cicloturismo. Assim, os utilizadores do veiculo projetado têm o privilégio de ter como painel de fundo das suas viagens, o coração da natureza, disfrutando do conforto e da segurança que este proporciona, e ainda como resultado das mesmas, um estilo de vida mais saudável. De forma sequencial e organizada, utilizando como base a Metodologia de Ulrich e Eppinger, são notáveis os passos que foram dados para obter o produto final. Para além dos fortes conceitos de conforto, estabilidade, engenharia e ergonomia, é primordial salientar toda a importância do Design, uma vez que influenciou a disposição do veículo de quatro rodas, do início ao fim.