Luiz Bueno da Silva

Analysis of air temperature changes on blood pressure and heart rate and performance of undergraduate students

BACKGROUND The increase in air temperature has been associated with human deaths, some of which are related to cardiovascular dysfunctions, and with the reduction of physical and cognitive performance in humans. OBJECTIVE To analyze the relationship between blood pressure (BP) and heart rate (HR) and the cognitive performance of students who were submitted to temperature changes in classrooms. METHODS The university students answered a survey that was adapted from the Battery of Reasoning Tests over 3 consecutive days at different air temperatures while their thermal state and HR were measured. During those 3 days, BP and HR were evaluated before and after the cognitive test. RESULTS The average and final HR increased at high temperatures; the tests execution time was reduced at high temperatures; and the cognitive tests was related to Mean BP at the beginning of the test, the maximum HR during the test and the air temperature. CONCLUSIONS The cognitive performance of undergraduate students in the field of engineering and technology will increase while performing activities in a learning environment with an air temperature of approximately 23.3°C (according to their thermal perception), if students have an initial MBP of 93.33 mmHg and a 60 bpm HRmax.

ESTATÍSTICA MULTIVARIADA: APLICAÇÃO DA ANÁLISE FATORIAL NA ENGENHARIA DE PRODUÇÃO

A Estatistica Multivariada permite o estudo de fenomenos complexos, pois realiza o tratamento de diversas variaveis simultaneamente, mesmo quando nao se conhece o modelo teorico das relacoes entre as variaveis. A Analise Fatorial, uma das tecnicas da estatistica multivariada, pode ser aplicada quando ha uma grande quantidade de dados e busca-se a sua sumarizacao com fatores latentes, que sao definidos atraves de comportamento semelhantes entre as variaveis. Este artigo tem como objetivo fazer uma revisao da literatura sobre a Estatistica Multivariada de dados e mostrar a aplicacao dessa tecnica de analise na Engenharia de Producao. O Inventario de Estresse em Enfermeiros, composto por 44 variaveis, foi aplicado a 391 individuos. A aplicacao da Analise Fatorial extraiu oito fatores determinantes para o estresse, que pode servir como subsidio para seu gerenciamento.

Aplicação de método e técnica multivariados para previsão de variáveis termoambientais e perceptivas

An ergonomically ideal environment for bank services needs to be thermally adequate, mainly according to the thermal perceptions of those responsible for the productivity, namely, human beings. This research has made it possible to recognize the relevant thermo-environmental characteristics of these activities and, based on the collected data, to apply the Linear Regression method and Discriminant Analysis exploratory technique to determine the thermal variables that may best represent the employees reported thermal sensations. For this purpose, the variables of thermal balance and sensation of each worker were determined, based on available international standards. It was found that the dry bulb temperature was the one that better represented these preferences. In the comfort situation, 23.79oC was the ideal temperature for these activities to be performed with thermal satisfaction.

Modeling Bayesian Networks from a conceptual framework for occupational risk analysis

Occupational risk is the possibility that some element included in a particular work environment can cause damage to someone’s health. Thereby, the risk is understood as the product of probability and consequences. In this sense, risk analysis through probabilistic stochastic techniques, such as Bayesian networks (BN), becomes an important tool to analyze occupational risks. Thus, this article aims to show how BNs are being used in the field of occupational risk analysis, and to develop a conceptual framework for the construction of the BNs. Therefore, a systematic review analogous to the Statement for Reporting Systematic Reviews (PRISMA) protocol was performed, which allowed the evaluation of learning methods with the BN, building models and also for us propose a conceptual framework for the implementation of BNs in the analysis of occupational risks.

APLICAÇÃO DO MÉTODO SERVQUAL NA AVALIAÇÃO DA SATISFAÇÃO DE CLIENTES DE UMA ACADEMIA DE GINÁSTICA

O crescente numero de academias de ginastica e consequentemente da demanda pelos servicos oferecidos neste tipo de empreendimento, e sobretudo a alta rotatividade, ou seja, a grande dificuldade apresentada na retencao de clientes levaram a investigacao e aprofundamento do tema proposto. A qualidade dos servicos e de dificil mensuracao e depende de diversos fatores ate que atenda as expectativas dos clientes e possa ser reconhecida pelos mesmos. Nem todas as empresas tem conseguido atingir as reais necessidades de seus clientes. Na tentativa de analisar a qualidade dos servicos prestados em uma academia de ginastica realizou-se uma pesquisa com a participacao de 92 clientes. Como instrumento de pesquisa utilizou-se uma adaptacao da escala SERVQUAL, que compara expectativas com percepcoes dos clientes em relacao as cinco dimensoes da qualidade: tangibilidade, responsabilidade, confiabilidade, empatia e garantia, tendo como base uma pesquisa qualitativa aplicada aos clientes da academia. Como resultado, obteve-se um panorama geral da qualidade percebida pelos clientes, dos servicos oferecidos, mostrando os pontos fortes e fracos do sistema.

Physiological variables in energy expenditure estimation by actigraphy: a systematic review protocol

Background: Energy expenditure measurement based on movement quantity is showed as a relevant alternative in clinical and research contexts. The best recommended and validated methods are expensive and inconvenient to field measurement, limiting the use to the laboratory. Lately, several devices have been developed to identify and classify activities by body movements, showing acceptable outcomes. These devices and techniques have been used to estimate energy expenditure in many physical activities situations. However, for this, is necessary include physiological variables. Methods: We propose a systematic review to identify evidence of influence and relevancy of physiological variables in energy expenditure measurement by actigraphy. We will search for Academic Search Complete, Scopus, Web of Science, Science Direct, Pubmed, and Informaworld by Francis & Taylor databases. Discussion: The outcomes will be synthesized to identify variables used in energy expenditure calculation methods and analyze the error between measured and calculated values considering the influence of physiological variables on this.

The Influence of the Metabolism in the PMV Model from ISO 7730 (2005)

Thermal comfort is one of the most influential variable to the measurable environmental quality. The most used mechanism to measure thermal comfort in a moderate environment is the Predicted Mean Vote (PMV) of the ISO 7730 standard [1]. Studies show discrepancies between the PMV and the occupants’ thermal sensation vote (TSV). The purpose of this study is to analyze the influence of the metabolism on the PMV model that represents the real sensation of students while working on a smart environment. Personal and lifestyle data was collected through questionnaires. The metabolism was calculated through six different methods. A comparison found that the study of Gilani et al. [2] was more accurate considering the TSV. Statistical tests were used to analyze the difference and compare the groups of quantitative, binary and nominal variables with significance level of 0,05. Using Generalized Linear Models (GLM) and the metabolism model of Gilani et al. [2] two models were adjusted. It was shown that gender and drug (medicaments) usage have an influence of approximate 10% over the metabolism. The new models were used to calculate PMVx and PMVy. Both PMVx and PMVy were found to be closer to the TSV than the PMV calculated with the metabolism obtained through the activity (1,2 met), though limited by the results from Gilani et al. [2]. These results show that the evolution of the environments such as the new smart teaching environments drive the need for improvement in thermal comfort studies using personal variables.

Relationship between psychosocial factors and musculoskeletal disorders in footwear industry workers

This study evaluated the effects of psychosocial factors on the risk of WRMD symptoms in Brazilian footwear industry workers. The workers’ perceptions regarding psychosocial factors and frequency of body pain were collected through a self-administered questionnaire. Logistic regression modeling was used to estimate the risk (Odds Ratio) of a worker more frequently exhibiting a symptom due to psychosocial factors. It was observed that some psychosocial factors, such as stress, contribute to WRMD in men, increasing the chance of symptoms in the knee (OR=3.07; p-value=0.036). In women, the ‘job dissatisfaction’ factor contributes to WRMD, increasing the chance of pain in the elbow (OR=4.83; p-value=0.007). It was concluded that a greater number of psychosocial factors influences the development of WRMD in male workers, although the effect these factors be discreet. In women, less psychosocial factors are related to WRMD, however its influence is very significant.

Risk of WMSDs in monofunctional and multifunctional workers in a Brazilian footwear company

This study aimed to analyze the risk of musculoskeletal disorders in monofunctional and multifunctional workers in a footwear company. The sample comprised 114 workers in the shoe production sector. The method Occupational Repetitive Actions was used to assess the risk of work-related musculoskeletal disorders (WMSDs). Proportional odds models were constructed, relating the risk of WMSDs to the type of work and the worker’s level of multifunctionality. For monofunctional workers, exposure to the higher risk was related to cycle time and the technical actions within their activities, whereas for multifunctional workers, it was related to the range of motion, use of gloves and precision needed in activities. For monofunctional workers, greater risks were associated with a short activity cycle, whereas for multifunctional workers, they were associated with complementary and organizational factors. Moreover, workers whose intracellular activities were less than 30% of the total appeared to be less exposed to the risk of WMSDs.

Sound pressure and temperature centering of material and sterilization

Objective: Gauge the sound pressure and temperature levels emitted by the equipment of the drying and sterilization rooms of the Material and Sterilization Center and compare them with the current legislation. Method: It is an experimental study with a quantitative approach, implemented in a school hospital in Joao Pessoa-PB. The data were obtained by a sound pressure meter and a thermal stress meter in September 2016. Results and Discussion: The data evidenced high sound pressure levels, reaching a mean of 71.25 and 76.25 dB (A), in the drying and sterilization rooms respectively. The levels found do not exceed that recommended by NR15 (Regulatory Norm 15) which is 85dB(A), but NBR 10152/87 (Brazilian Norm 10152/87) indicates levels between 45 and 55 dB(A) for acoustic well-being. As for the temperature the measured mean ranged between 24.91 and 25.87 °C. Conclusion: The levels of sound pressure and temperatures found in the environment can cause physiopsychological changes in the professionals that works in this services. Keywords: Sound pressure; Temperature; Material and Sterilization Center