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To explore the health risks of the interactive effects between PM2.5 and ozone on cardiovascular mortality in Chengdu.Daily data on the mortality of cardiovascular diseases, including data for both men and women, during 2014-2016 were collected. The meteorological data, the daily average of particulate matter with aerodynamic diameter less than 2.5 micrometers (PM2.5), and the daily ozone 8 h maximum concentration (OThe highest health risks of PM2.5 and OThere was a synergistic amplification effect between high concentrations of PM2.5 and high concentrations of O

The human body, as an open system in nature, whose health is bound to be affected by climatic conditions. And these conditions have a very important impact on the length and quality of the elderly life especially. In this paper, a new method for solving fuzzy multiple attribute decision making problem is presented, where the attribute values are trapezoidal fuzzy numbers. First, based on fuzzy multiple attribute decision method, the comfort parameter of climate vector is got. Then by using the judgment matrices about the attributes given by the experts, the attribute weight vector is acquired. Finally, three similar degrees between trapezoidal fuzzy numbers are introduced to provide the supported tools for the decision-makers and the pensioners to choose the more suitable address for pension.

This study aimed to investigate the effects of sleep deprivation on postural control, subjective fatigue assessment and psychomotor performance, and to assess the efficiency of an objective posturographic test as an indicator of mental fatigue. Postural sway using static posturography (Romberg's test), subjective fatigue assessment (Stanford Sleepiness Scale) and psychomotor performance (Sternberg dual-task test) were assessed in 12 subjects before and after 24 h of sustained wakefulness. After sustained wakefulness, the Romberg test parameters of circumference area and rectangle area with the eyes-closed, and standard deviation in the anterior–posterior direction with the eyes-open were significantly higher compared with baseline values (before sustained wakefulness). Subjective fatigue assessment scores were also significantly increased, while psychomotor performance was unchanged. Sleep deprivation can arouse a feeling of fatigue and can affect postural stability, hence an objective posturographic test score may be useful as an indicator of mental fatigue.

Introduction: Exposure to high +G z acceleration forces on a centrifuge or in an aircraft can severely decrease cerebral blood perfusion and cause rapid G-induced loss of consciousness. However, milder acceleration may gradually reduce cerebral blood flow and affect cognitive function in subtler ways. This study used lower body negative pressure (LBNP) to mimic +G z circulatory effects in order to study cerebral hemodynamics and brain function. Methods: Subjects were 15 healthy men, 19-21 yr of age. They were exposed to LBNP at two levels for 5 min each separated by a 10-min recovery period. The conditions were low (LO), -4.00 kPa (-30 mmHg) and high (HI), -6.67 kPa (-50 mmHg). Variables measured before, during, and after LBNP included cerebral blood flow velocity (CBFV) in the middle cerebral artery, blood oxygen saturation (S a O 2 ), heart rate (HR), blood pressure, P300 of event-related EEG potentials, reaction time, and tracking error. Results: LO significantly reduced CBFV at 4 and 5 min, increased HR, and decreased the amplitude of P300, but none of the other variables changed from baseline. In contrast, HI produced significant changes in most variables: CBFV decreased at 2 min and then fell further at 4 and 5 min, HR increased, and S a O 2 decreased. Significant neurocognitive changes included increased latency and reduced amplitude of P300, slower reaction time, and greater tracking error. Conclusion: The higher level of LBNP used here reduced cerebral perfusion sufficiently to impair neurocognitive function. This model may be useful for further studies of these and other variables under closelv controlled conditions.