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831.
The objective of this paper is to investigate the position of the resultant force in involute spline coupling teeth due to the contact pressure distribution for both ideal and misaligned conditions. In general, spline coupling teeth are in contact all along the involute profile and the load is far from uniform along the contact line. Theoretical models available in publications consider the resultant contact force as it is applied at the pitch diameter, and this study aims to evaluate the error introduced within the confines of a common approximation environment. This analysis is carried out through using finite element method (FEM) models, considering spline couplings in both ideal and misaligned conditions. Results show that the differences between the load application diameter and pitch diameter are not very obvious in both ideal and misaligned conditions; however, this ap- proximation becomes more important for the calculation of the tooth stiffness. 相似文献
832.
Andrea C. Goldfien Norena Norton Badway 《Community College Journal of Research & Practice》2014,38(2-3):122-130
Bridge programs, in which underprepared students gain the academic and technical skills necessary for college level courses and entry-level employment, are a promising initiative for expanding access to, and success in, community college education. For career pathways related to science, technology, engineering, or mathematics (STEM), bridge programs are critical for enlarging the pool of students who are exposed to, and can aspire to, STEM preparation. This study, conducted with support from the National Science Foundation Advanced Technological Education program, followed four community colleges for a year to understand local factors that facilitated or impeded implementation of a bridge program in which basic skills were contextualized in biotechnology. The findings are that implementation of a contextualized curriculum requires substantial faculty learning. Implementation of these bridge programs was facilitated by instructional leadership by both administration and faculty. Administration assisted in creating the conditions that supported learning by coordinating faculty schedules and funding faculty time for initial and ongoing program development. Faculty benefitted by the support of experienced team members who could guide interdisciplinary learning. Implementation was facilitated when team members met frequently and when faculty worked collaboratively to implement the curriculum. Recommendations include planning for faculty development, both for faculty collaboration and contextualizing curriculum. 相似文献
833.
The concept of open innovation captures the increasing propensity of firms to work across their traditional boundaries of operation. This phenomenon has largely been studied from the viewpoint of manufacturing businesses while services have received much less attention despite the predominant role they play in advanced economies. This paper focuses on open innovation in services, both as a subsector of the economy and as a component of the activities of manufacturing firms. We study the open innovation practices of business services firms and then consider the implications for open innovation of the adoption of a service inclusive business model by manufacturing firms. Our analyses are based on a unique dataset with information on open innovation activities amongst UK firms. Overall, engagement in open innovation increases with firm size and R&D expenditure. Business services are more active open innovators than manufacturers; they are more engaged in informal relative to formal open innovation practices than manufacturers; and they attach more importance to scientific and technical knowledge than to market knowledge compared to manufacturing firms. Open innovation practices are also associated with the adoption of a service inclusive business model in manufacturing firms and service-integrated manufacturers engage in more informal knowledge-exchange activities. The paper contributes towards a reconceptualisation of open innovation in service businesses and a deeper evidence-based understanding of the service economy. 相似文献
834.
Ines Poto?njak Goran Te?ovi? Andrea Te?ija Kuna Mario ?tefanovi? Orjena ?aja 《Biochemia medica : ?asopis Hrvatskoga dru?tva medicinskih biokemi?ara / HDMB》2014,24(3):396-402
Congenital Cytomegalovirus (CMV) infection and alpha 1-antitrypsin (A1AT) deficiency are separately well described entities, but their simultaneous occurrence can pose a special challenge to a clinician, especially dealing with optimal diagnostic as well as therapeutic approach. Congenital CMV infection is the most common vertically transmitted infection in developed countries. In 85–95% of newborns it runs asymptomatic, while in others it is presented with jaundice, petechias, hepatosplenomegaly and central nervous system damage. A1AT deficiency is on the other hand, the most common genetic liver disease in children, and the clinical spectrum varies from the accidentally detected increased levels of transaminases through to the severe infant cholestasis that can progress to cirrhosis. The following case report describes a two-month old male with severe clinical presentation of congenital CMV infection probably exacerbated due to A1AT deficiency comorbidity. The clinical manifestations and unusually difficult clinical signs this infant presented lead to assumption that the additional liver damage exists. Extensive laboratory analyses were performed, including PCR for CMV DNA, A1AT serum concentration, A1AT genotyping, followed and confirmed with phenotyping. Patient was treated parenteral with ganciclovir, what continued with oral valganciclovir and supportive therapy. Intensive and thorough supportive treatment of the infant resulted in satisfactory progress and excellent outcome. Patient was followed-up till the age of 18 months. The presented case provides excellent example about successful overcoming obstacles in differential diagnosis of A1AT in neonates and infants. Medical charts analysis was the methodology used in making this report. 相似文献
835.
Andrea N. Eagleman 《Sport Management Review》2013,16(4):488-497
National governing bodies (NGB) of sport are not-for-profit organisations that typically receive less mainstream media coverage and have much smaller marketing budgets than mainstream professional sports. Therefore, they must seek alternative methods from mainstream media and traditional marketing in order to increase brand awareness and reach fans and stakeholders. While all sport organisations stand poised to benefit from social media, NGBs seem to be a segment of the sport industry uniquely positioned to capitalise on social media's benefits. Because there is currently no known literature on NGBs’ use of social media, this study examined the role that social media plays within NGBs in the United States including employees’ acceptance of social media, motivations to use social media, and the organisation's current usage of social media. An online survey was distributed to NGB employees in the spring of 2012, and results revealed that contrary to studies on other sport organisations, NGB employees reported high levels of acceptance and motivation to use social media regardless of demographic factors. Additionally, NGBs seemed to use social media as a communications tool to a greater degree than as a marketing tool. Implications for international and niche sport organisations are presented in the conclusion. 相似文献
836.
Andrea Viggiano Sergio Chieffi Domenico Tafuri Giovanni Messina Marcellino Monda Bruno De Luca 《Journal of sports sciences》2013,31(1):46-62
Vividness and controllability of relaxing and energizing imagery by efficient and less efficient imagers. 相似文献
837.
Andrea Margaret McNeilly Marie Murphy Jane McEneny Tom Trinick George Burke 《Journal of sports sciences》2013,31(8):725-732
Abstract Individuals with impaired glucose tolerance (IGT) are at greater risk of developing diabetes than in normoglycaemia. The aim of this study was to examine the effects of 12-weeks exercise training in obese humans with IGT. Eleven participants (6 males and 5 females; 49±9 years; mean Body Mass Index (BMI) 32.4 kg · m?2), completed a 12-week brisk walking intervention (30 min per day, five days a week (d · wk?1), at 65% of age-predicted maximal heart rate (HRmax). Anthropometric measurements, dietary intake, pulse wave velocity (PWV, to determine arterial stiffness) and blood pressure (BP) were examined at baseline and post intervention. Fasting blood glucose, glycosylated haemoglobin, insulin, blood lipids, indices of oxidative stress and inflammation (lipid hydroperoxides; superoxide dismutase; multimeric adiponectin concentration and high-sensitivity C-reactive protein) were also determined. Post intervention, PWV (9.08±1.27 m · s?1 vs. 8.39±1.21 m · s?1), systolic BP (145.4±14.5 vs. 135.8±14.9 mmHg), triglycerides (1.52±0.53 mmol . L?1 vs. 1.31±0.54 mmol . L?1), lipid hydroperoxides (1.20±0.47 μM · L?1 vs. 0.79±0.32 μM · L?1) and anthropometric measures decreased significantly (P < 0.05). Moderate intensity exercise training improves upper limb vascular function in obese humans with IGT, possibly by improving triglyceride metabolism, which may subsequently reduce oxidative stress. These changes were independent of multimeric adiponectin modification and alterations in other blood biomarkers. 相似文献
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