2,155 research outputs found


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    Control strategies for cleaning robots in domestic applications: A comprehensive review:

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    Service robots are built and developed for various applications to support humans as companion, caretaker, or domestic support. As the number of elderly people grows, service robots will be in increasing demand. Particularly, one of the main tasks performed by elderly people, and others, is the complex task of cleaning. Therefore, cleaning tasks, such as sweeping floors, washing dishes, and wiping windows, have been developed for the domestic environment using service robots or robot manipulators with several control approaches. This article is primarily focused on control methodology used for cleaning tasks. Specifically, this work mainly discusses classical control and learning-based controlled methods. The classical control approaches, which consist of position control, force control, and impedance control , are commonly used for cleaning purposes in a highly controlled environment. However, classical control methods cannot be generalized for cluttered environment so that learning-based control methods could be an alternative solution. Learning-based control methods for cleaning tasks can encompass three approaches: learning from demonstration (LfD), supervised learning (SL), and reinforcement learning (RL). These control approaches have their own capabilities to generalize the cleaning tasks in the new environment. For example, LfD, which many research groups have used for cleaning tasks, can generate complex cleaning trajectories based on human demonstration. Also, SL can support the prediction of dirt areas and cleaning motion using large number of data set. Finally, RL can learn cleaning actions and interact with the new environment by the robot itself. In this context, this article aims to provide a general overview of robotic cleaning tasks based on different types of control methods using manipulator. It also suggest a description of the future directions of cleaning tasks based on the evaluation of the control approaches

    The Federated Practice of Soccer Influences Hamstring Flexibility in Healthy Adolescents: Role of Age and Weight Status

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    The aim of this study was to compare the hamstring flexibility between federated soccer and non-federated adolescents, and also to evaluate the effect of age and weight status on hamstring flexibility. The participants were 234 students (11-18 years old) divided into: (i) G1: non-federated (n = 127), and (ii) G2: federated in soccer (n = 107). The deep flexion of the trunk (DF) test and the sit and reach test (SRT) were performed. G2 showed higher values for the DF and SRT compared to G1 (p < 0.05). Both flexibility tests correlated positively (r = 0.4, p < 0.001). Body mass index (BMI) was negatively correlated with the DF test (r = -0.3, p < 0.001), but not with the SRT. Divided by BMI, the underweight and normal weight groups had higher scores in the DF test compared with the overweight and obese groups (p < 0.001). BMI was negatively correlated with hamstring flexibility. Federated soccer students present higher scores of hamstring flexibility

    Prevalence of chronic kidney disease and comorbidities in isolated African descent communities (PREVRENAL): methodological design of a cohort study

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    Background: Chronic kidney disease (CKD) is considered a serious public health problem, both in Brazil and worldwide, with an increasing number of cases observed inrecent years. Especially, CKD has been reported to be highly prevalent in those of African descent. However, Brazil lacks data from early-stage CKD population studies, and the prevalence of CKD is unknown for both the overall and African descent populations. Hence, the present study aims to estimate the prevalence of early-stage CKD and its associated risk factors in African-Brazilians from isolated African-descent communities. Herein, the detailed methodology design of the study is described. Methods: This population-based, prospective, longitudinal, cohort study (PREVRENAL) is performed in three stages: first, clinical, nutritional, and anthropometric evaluationsmeasurements of serum and urinary markersand examinations of comorbidities were performed. Second, repeated examinations of individuals with CKD, systemic arterial hypertension, and/or diabetes mellitusimage screeningand cardiac risk assessment were performed. Third, long-term monitoring of all selected individuals will be conducted (ongoing). Using probability sampling, 1539 individuals from 32 communities were selected. CKD was defined asaglomerular filtration rate (GFR) 30 mg/day. Discussion: This study proposes to identify and monitor individuals with and without reduced GFR and high albuminuria in isolated populations of African descendants in Brazil. As there are currently no specific recommendations for detecting CKD in African descendants, four equations for estimating the GFR based on serum creatinine and cystatin C were used and will be retrospectively compared. The present report describes the characteristics of the target population, selection of individuals, and detection of a population at risk, along with the imaging, clinical, and laboratory methodologies used. The first and second stages have been concluded and the results will be published in the near future. The subsequent (third) stage is the long-term, continuous monitoring of individuals diagnosed with renal abnormalities or with CKD risk factors. The entire study population will be re-evaluated five years after the study initiation. The expectation is to obtain information about CKD evolution among this population, including the progression rate, complication development, and cardiovascular events.Research Support Foundation of Maranhao (Fundacao de Amparo a Pesquisa do Maranhao - FAPEMA)Univ Fed Maranhao, Kidney Dis Prevent Ctr, Sao Luis, MA, BrazilUniv Fed Maranhao, Dept Med 1, Sao Luis, MA, BrazilUniv Fed Maranhao, Dept Publ Hlth, Sao Luis, MA, BrazilUniv Fed Maranhao, Kidney Dis Prevent Ctr, Sao Luis, MA, BrazilUniv Fed Maranhao, Dept Physiol Sci, Sao Luis, MA, BrazilUniv Sao Paulo, Ribeirao Preto Sch Med, Dept Pathol & Radiol, Ribeirao Preto, SP, BrazilUniv Estado Rio De Janeiro, Dept Internal Med, Rio De Janeiro, RJ, BrazilUniv Fed Sao Paulo, Paulista Sch Med, Discipline Nephrol, Sao Paulo, SP, BrazilUniv Fed Sao Paulo, Paulista Sch Med, Discipline Nephrol, Sao Paulo, SP, BrazilWeb of Scienc

    Investigating the impact of visual perspective in a motor imagery-based brain-robot interaction: A pilot study with healthy participants

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    IntroductionMotor Imagery (MI)-based Brain Computer Interfaces (BCI) have raised gained attention for their use in rehabilitation therapies since they allow controlling an external device by using brain activity, in this way promoting brain plasticity mechanisms that could lead to motor recovery. Specifically, rehabilitation robotics can provide precision and consistency for movement exercises, while embodied robotics could provide sensory feedback that can help patients improve their motor skills and coordination. However, it is still not clear whether different types of visual feedback may affect the elicited brain response and hence the effectiveness of MI-BCI for rehabilitation.MethodsIn this paper, we compare two visual feedback strategies based on controlling the movement of robotic arms through a MI-BCI system: 1) first-person perspective, with visual information that the user receives when they view the robot arms from their own perspective; and 2) third-person perspective, whereby the subjects observe the robot from an external perspective. We studied 10 healthy subjects over three consecutive sessions. The electroencephalographic (EEG) signals were recorded and evaluated in terms of the power of the sensorimotor rhythms, as well as their lateralization, and spatial distribution.ResultsOur results show that both feedback perspectives can elicit motor-related brain responses, but without any significant differences between them. Moreover, the evoked responses remained consistent across all sessions, showing no significant differences between the first and the last session.DiscussionOverall, these results suggest that the type of perspective may not influence the brain responses during a MI- BCI task based on a robotic feedback, although, due to the limited sample size, more evidence is required. Finally, this study resulted into the production of 180 labeled MI EEG datasets, publicly available for research purposes

    Overall and cause-specific excess mortality in HIV-positive persons compared with the general population: Role of HCV coinfection

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    We aimed to estimate overall and cause-specific excess mortality of HIV-positive patients compared with the general population, and to assess the effect of risk factors.We included patients aged >19 years, recruited from January 1, 2004 to May 31, 2014 in Cohort of the Spanish Network on HIV/AIDS Research. We used generalized linear models with Poisson error structure to model excess mortality rates.In 10,340 patients, 368 deaths occurred. Excess mortality was 0.82 deaths per 100 person-years for all-cause mortality, 0.11 for liver, 0.08 for non-AIDS-defining malignancies (NADMs), 0.08 for non-AIDS infections, and 0.02 for cardiovascular-related causes. Lower CD4 count and higher HIV viral load, lower education, being male, and over 50 years were predictors of overall excess mortality. Short-term (first year follow-up) overall excess hazard ratio (eHR) for subjects with AIDS at entry was 3.71 (95% confidence interval [CI] 2.66, 5.19) and 1.37 (95% CI 0.87, 2.15) for hepatitis C virus (HCV)-coinfected; medium/long-term eHR for AIDS at entry was 0.90 (95% CI 0.58, 1.39) and 3.83 (95% CI 2.37, 6.19) for HCV coinfection. Liver excess mortality was associated with low CD4 counts and HCV coinfection. Patients aged ‚Č•50 years and HCV-coinfected showed higher NADM excess mortality, and HCV-coinfected patients showed increased non-AIDS infections excess mortality.Overall, liver, NADM, non-AIDS infections, and cardiovascular excesses of mortality associated with being HIV-positive were found, and HCV coinfection and immunodeficiency played significant roles. Differential short and medium/long-term effects of AIDS at entry and HCV coinfection were found for overall excess mortality.The RIS cohort (CoRIS) is supported by the Instituto de Salud Carlos III through the Red Tem√°tica de Investigaci√≥n Cooperativa en Sida (RD06/006 and RD12/0017/0018) as part of the Plan Nacional R+D+I and cofinanced by ISCIII-Subdirecci√≥n General de Evaluaci√≥n y el Fondo Europeo de Desarrollo Regional (FEDER)S
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