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51.
Work-related musculoskeletal disorders (WRMD) are the result of the combination of different risk factors. They are very common among computer workers, mainly when neck and upper limbs are considered. Forty-two office workers from a public university participated in this study. They were divided into two groups: Symptomatic Subjects (SS, n=20) and Asymptomatic Subjects (AS, n=22), according to the Nordic Musculoskeletal Questionnaire (NMQ). Psychosocial indicators were assessed using the Job Content Questionnaire (JCQ) and Utrecht Work Engagement Scale (UWES). Workplaces were evaluated according to the Ergonomic Workplace Analysis (EWA), proposed by the Finnish Institute of Occupational Health. The NMQ showed higher weekly prevalence of complaints on neck, shoulders and wrist/hands (p=0.00) among SS. The annual prevalence of symptoms on wrist/hands was also higher among SS (p=0.02). The JCQ did not show any difference between groups (p>0.05). Higher proportion of servers with 'high level' of engagement, dedication and absorption, according to UWES, was identified among SS (p<0.01). EWA showed worse scores for 'Work Site', 'Job Content' and 'Repetitiveness of the Work' among SS (p<0.05). Servers are exposed to physical and psychosocial risk factors that can contribute to the development of WRMD. Work conditions need to be change in order to improve musculoskeletal health.  相似文献   
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This study aimed to perform an ergonomic evaluation of industrial processes and products - upholstered sofas - produced in the furniture cluster of Ubá-MG. The used material was collected from two sofas upholstered industries associated with the union of the furniture industries of Ubá region, located in Minas Gerais estate, Brazil. As for the product were evaluated dimensionally 29 upholstered sofas, with 12 being produced by industry "A" and 17 being produced by industry "B". As for the process, were evaluated: the socioeconomic profile of the worker and environmental factors of lighting and noise. The main results of this study showed that the upholstered sofas produced by industries, in general, fulfilled to the recommendations set out in the work in relation to the backrest height and useful seat depth. All the sofas, however, proved to be inadequate in relation to the seat height to the floor and the dimensions of the armrests Regarding environmental aspects, it was observed that in both industries, the activities in most jobs are performed under adverse conditions to the health and safety of workers and nonconformity with the limits set by Brazilian regulatory standard used in this work.  相似文献   
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Pilates method is employed for physical and mental conditioning. Elderly people could be benefited from a patterned and regulated conditioning work based on Pilates method. We performed a systematic review to assess the evidence on the effects of Pilates method in physical fitness on older adults. Our search included the following databases: MEDLINE-PubMed, Scopus and CINAHL Plus with Full Text via EBSCO and SPORTDiscus databases (up to April 2014). A summary of the results was performed using a best evidence synthesis and was reported according to the systematic review method proposed by Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) statement. The Physiotherapy Evidence Database (PEDro) scale was used to assess the methodology quality of selected studies. Seventeen experimental studies were included in this review. Fourteen were randomized controlled trials (RCT) and three clinical controlled trials (CCT). Quality scores according to PEDro indicate low quality of the included studies (range 1–6, mean 3.8?±?1.2). The most studied components related to physical fitness were neuromotor fitness (n?=?11), muscle strength (n?=?8), cardiorespiratory endurance (n?=?4), body composition (n?=?4) and flexibility (n?=?4). Results indicate that Pilates method seems to present positive effects in neuromotor fitness, especially in static and dynamic balance. Related to the other components of physical fitness (cardiorespiratory endurance, muscle strength, body composition and flexibility), contradictory results were observed. The Pilates method indicates to be an appropriate exercise modality in order to improve balance on older adults. Nevertheless, more intervention research is needed to build a solid knowledge base about the health benefits of Pilates method on older people, especially regarding the other components of physical fitness.  相似文献   
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The Family Adaptability and Cohesion Scales (FACES) are one of the most used instruments in the study of family relations, assessing relevant dimensions of family functioning. This study aims to examine the relationship between cohesion, communication and family satisfaction, measured by FACES IV, and the dimensions of discipline inventory (DDI). The sample consisted of 380 subjects (190 adolescents and 190 parents). Fathers are the main users of physical discipline and boys are the main targets of most discipline practices. Regarding the association of the DDI and FACES, families with a balanced cohesion use less punitive discipline, families with enmeshed cohesion and families with disengaged cohesion have higher and less use of the analyzed disciplinary practices respectively. Considering the results, it may be useful to work together with families to promote the use of positive disciplinary methods and work their communication skills in order to improve cohesion and consequently family satisfaction.  相似文献   
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In this paper, we present a study about the estimation of the serial correlation for Markov chain models which is used often in the quality control of autocorrelated processes. Two estimators, non-parametric and multinomial, for the correlation coefficient are discussed. They are compared with the maximum likelihood estimator [U.N. Bhat and R. Lal, Attribute control charts for Markov dependent production process, IIE Trans. 22 (2) (1990), pp. 181–188.] by using some theoretical facts and the Monte Carlo simulation under several scenarios that consider large and small correlations as well a range of fractions (p) of non-conforming items. The theoretical results show that for any value of p≠0.5 and processes with autocorrelation higher than 0.5, the multinomial is more precise than maximum likelihood. However, the maximum likelihood is better when the autocorrelation is smaller than 0.5. The estimators are similar for p=0.5. Considering the average of all simulated scenarios, the multinomial estimator presented lower mean error values and higher precision, being, therefore, an alternative to estimate the serial correlation. The performance of the non-parametric estimator was reasonable only for correlation higher than 0.5, with some improvement for p=0.5.  相似文献   
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The linear ordering problem (LOP) is an NP\mathcal{NP}-hard combinatorial optimization problem with a wide range of applications in economics, archaeology, the social sciences, scheduling, and biology. It has, however, drawn little attention compared to other closely related problems such as the quadratic assignment problem and the traveling salesman problem. Due to its computational complexity, it is essential in practice to develop solution approaches to rapidly search for solution of high-quality. In this paper we propose a new algorithm based on a greedy randomized adaptive search procedure (GRASP) to efficiently solve the LOP. The algorithm is integrated with a Path-Relinking (PR) procedure and a new local search scheme. We tested our implementation on the set of 49 real-world instances of input-output tables (LOLIB instances) proposed in Reinelt (Linear ordering library (LOLIB) 2002). In addition, we tested a set of 30 large randomly-generated instances proposed in Mitchell (Computational experience with an interior point cutting plane algorithm, Tech. rep., Mathematical Sciences, Rensellaer Polytechnic Institute, Troy, NY 12180-3590, USA 1997). Most of the LOLIB instances were solved to optimality within 0.87 seconds on average. The average gap for the randomly-generated instances was 0.0173% with an average running time of 21.98 seconds. The results indicate the efficiency and high-quality of the proposed heuristic procedure.  相似文献   
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This article presents the development of a Residential Care Youth Needs Assessment (RCYNA) instrument. In two studies, initial evidence regarding the RCYNA psychometric properties was obtained using a sample of youth in residential care. Results show adequate levels of content and face validity, reliability and concurrent validity.  相似文献   
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