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351.
Studies on packaging accessibility are still incipient in Brazil. Many of these packagings can represent a challenge to users, whether due to non-informative labels, tricky tabs or seals, or even those that need strength to open. This paper brings a simple test to determine the necessary torque force to open PET bottles, and to predict the amount of users that could not open it. The findings suggest that a considerable amount of users could not open it or would have some difficulties to exert the necessary force.  相似文献   
352.
353.
Shift workers from control centers of electrical systems are a group that has received little attention in Brazil. This study aimed to compare workers' job satisfaction at five control centers of a Brazilian company electrical system, and according to their job titles. Method: The Organization Satisfaction Index (OSI) questionnaire to assess job satisfaction was used. ANOVA was used to compare OSI means, according to job title and control center. The results showed that there is no difference in job satisfaction among job titles, but a significant difference was found according to the control center. A single organizational culture cannot be applied to several branches. It is required to implement actions that would result in job satisfaction improvements among workers of all studied control rooms centers. The high level of education of operators working in all centers might have contributed to the similar values of perceived satisfaction among distinct job titles.  相似文献   
354.
The purpose of this study was to evaluate the impact of introduction a new work tool on health and productivity of manual harvesting sugarcane workers. In this study it was performed aErgonomic Work Analysis (EWA) to analyze the work tool changes.The study included sugarcane workers, drivers, fiscals, and technical's safety at work.During the analysis process, 134 questionnaires were applied,aimed to identify the constraints that such workers are submitted,to evaluate the tool introduced, in order to propose modifications to improve it.The results showed a decrease in perceived exertion and discomfort, without compromising the cut quality. The main contributions of Ergonomic Work Analysis were the possibility of bringing the logic of the worker, in order to understand the inherent real work characteristics, to the process of developing the new tool. Besides, it was also noted that this methodology, based on the analysis workers activity in a real usage, as an application tool in design projects, providing innovations from the workers perspective.  相似文献   
355.
The purpose of this study was to compare the neuromuscular adaptations produced by strength-training (ST) and power-training (PT) regimens in older individuals. Participants were balanced by quadriceps cross-sectional area (CSA) and leg-press 1-repetition maximum and randomly assigned to an ST group (n = 14; 63.6 ± 4.0 yr, 79.7 ± 17.2 kg, and 163.9 ± 9.8 cm), a PT group (n = 16; 64.9 ± 3.9 yr, 63.9 ± 11.9 kg, and 157.4 ± 7.7 cm), or a control group (n = 13; 63.0 ± 4.0 yr, 67.2 ± 10.8 kg, and 159.8 ± 6.8 cm). ST and PT were equally effective in increasing (a) maximum dynamic and isometric strength (p < .05), (b) increasing quadriceps muscle CSA (p < .05), and (c) decreasing electrical mechanical delay of the vastus lateralis muscle (p < .05). There were no significant changes in neuromuscular activation after training. The novel finding of the current study is that PT seems to be an attractive alternative to regular ST to maintain and improve muscle mass.  相似文献   
356.
We study Bayesian dynamic models for detecting changepoints in count time series that present structural breaks. As the inferential approach, we develop a parameter learning version of the algorithm proposed by Chopin [Chopin N. Dynamic detection of changepoints in long time series. Annals of the Institute of Statistical Mathematics 2007;59:349–366.], called the Chopin filter with parameter learning, which allows us to estimate the static parameters in the model. In this extension, the static parameters are addressed by using the kernel smoothing approximations proposed by Liu and West [Liu J, West M. Combined parameters and state estimation in simulation-based filtering. In: Doucet A, de Freitas N, Gordon N, editors. Sequential Monte Carlo methods in practice. New York: Springer-Verlag; 2001]. The proposed methodology is then applied to both simulated and real data sets and the time series models include distributions that allow for overdispersion and/or zero inflation. Since our procedure is general, robust and naturally adaptive because the particle filter approach does not require restrictive specifications to ensure its validity and effectiveness, we believe it is a valuable alternative for dealing with the problem of detecting changepoints in count time series. The proposed methodology is also suitable for count time series with no changepoints and for independent count data.  相似文献   
357.
This work presents a framework of dynamic structural models with covariates for short-term forecasting of time series with complex seasonal patterns. The framework is based on the multiple sources of randomness formulation. A noise model is formulated to allow the incorporation of randomness into the seasonal component and to propagate this same randomness in the coefficients of the variant trigonometric terms over time. A unique, recursive and systematic computational procedure based on the maximum likelihood estimation under the hypothesis of Gaussian errors is introduced. The referred procedure combines the Kalman filter with recursive adjustment of the covariance matrices and the selection method of harmonics number in the trigonometric terms. A key feature of this method is that it allows estimating not only the states of the system but also allows obtaining the standard errors of the estimated parameters and the prediction intervals. In addition, this work also presents a non-parametric bootstrap approach to improve the forecasting method based on Kalman filter recursions. The proposed framework is empirically explored with two real time series.  相似文献   
358.

Despite great developmental efforts in recent decades, Latin America still presents high levels of poverty and inequality when compared to developed nations. As explored widely in the literature, one potential instrument to diminish these issues is financial inclusion, including the access and usage of financial services by all people. Specifically, this paper verifies if financial inclusion and technology adoption decrease the poverty headcount ratio and the Gini index (i.e., inequality) of 13 Latin America countries (Argentina, Bolivia, Brazil, Colombia, Costa Rica, Dominican Republic, Ecuador, El Salvador, Honduras, Panama, Paraguay, Peru, and Uruguay). To perform such analysis, an unbalanced panel dataset was built, and the Feasible Generalized Least Squares (FGLS) and the Limited Information Maximum Likelihood (LIML) techniques were employed. The results suggest that, in accordance with previous studies, financial inclusion is a powerful tool to tackle poverty and inequality. Additionally, the combined effects of financial inclusions and technology (i.e., mobile use) are also capable of decreasing the poverty and inequality levels. We discuss the policy implications of our findings and suggest a future research agenda.

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359.
A great deal of scholarship investigates the effects of parenting on adults who parent. While existing literature has identified the ways in which parenting affects parents adversely, we argue that more attention needs to be paid to how having children may enhance parents’ lives. Thus, we draw upon twenty-four in-depth interviews with young parents in order to investigate this process. First, we identify five ways in which parents say caregiving has changed their worldviews, relationships, and expectations, leading them to 1) erect barriers, 2) aspire for more, 3) view parenthood as a second chance, 4) hew a new path, and 5) make connections. Second, we uncover two central metaphors that parents rely on to explain the effect that having responsibility for children has had on their lives: the child as witness and the child as tether. We also point to future areas of investigation, arguing that only with an adequate understanding of what parenting does to parents can we understand what changing trends in families and inequality hold for ourselves and our futures.  相似文献   
360.
Reforms aimed at expanding learning for low-income children must do more than add hours and days to the school year; they must push beyond the traditional boundaries of school-based learning and find ways to maximize and integrate the assets that cities, districts, and communities can offer. This article reviews research on how schools are using extended learning time to promote student engagement and achievement. A key finding is that successful efforts use partnerships with outside organizations to provide academic support and enrichment activities that build students' skills and connections with an expanded network of supportive adults. The challenge is to ensure that these partnerships are not mere add-ons, designed only to plug extracurricular holes and seen as peripheral to the core academic work of schools. They must be part of a larger system that integrates in-school and out-of-school learning and improves outcomes for youth.  相似文献   
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