Hoyleharbo9474

This study proposed to investigate the thermal properties and subjective thermal discomfort of five virtual reality headsets, and their relationships. Twenty-seven university students used each of the five headsets for 45 min. CP-673451 Microclimate temperature and relative humidity were measured by miniature dataloggers. Infrared thermography was used to measure temperature distribution on the contact points between user's face and the headsets. Participants reported subjective thermal discomfort associated with using each headset. The average microclimate temperature and relative humidity increased by 7.8 °C and 3.5% respectively after headset use. Overall subjective thermal discomfort increased along with duration of use and came primarily from the display. Applying the linear mixed-effects model showed that subjective thermal discomfort is positively correlated with duration of use, microclimate temperature, relative humidity and display coverage area. Conversely, thermal discomfort is negatively correlated with total coverage area, with microclimate temperature acting as the most significant contributing factor. The headsets were ranked by pairing the objective measurements with subjective evaluations. The aim of this study was to employ validated biological markers to quantify the physiologic consequences of exposure to whole-body vibration (WBV) and evaluate the relative impact of mining vehicle operator vibration exposure on physiological responses as compared to vertical-axial dominant WBV. In a laboratory-based study with a repeated-measures design, we played actual field-measured floor vibration profiles into a 6-degree-of-freedom motion platform to create different realistic WBV exposures 1) vertical-dominant vibration collected from long-haul trucks, 2) multi-axial vibration collected from mining heavy equipment vehicles, and 3) no vibration (control condition). Circulating biomarkers of interest were cortisol and catecholamines (epinephrine and norepinephrine) to assess physiological stress, interleukin-6 (IL-6) and tumor necrosis factor-α (TNFα) to test for inflammation, thiobarbituric acid reactive substances (TBARS) to measure oxidative stress, and myoglobin and plasma creatine kinase to assess muscle damage. We collected blood samples at pre-exposure (0 h), during-exposure (2 and 4 h), and 2 h into recovery after the WBV exposure (6 h) in all four exposure conditions. The results showed that a single, 4-h acute exposure to WBV may not be sufficient to induce skeletal muscle damage, inflammation or physiologic stress measurable in the blood. No significant differences were observed between conditions for any of the biomarkers that could be attributed to the exposure contrast between vertical-dominant and multi-axial WBV exposures. These findings further indicate known complications of WBV exposure likely arise secondary to chronic, repeated exposures that give rise to subclinical stresses that were not captured here. OBJECTIVES Investigate whether a range of cooling methods can extend tolerance time and/or reduce physiological strain in those working in the heat dressed in a Class 2 chemical, biological, radiological, nuclear (CBRN) protective ensemble. METHODS Eight males wore a Class 2 CBRN ensemble and walked for a maximum of 120 min at 35 °C, 50% relative humidity. In a randomised order, participants completed the trial with no cooling and four cooling protocols 1) ice-based cooling vest (IV), 2) a non-ice-based cooling vest (PCM), 3) ice slushy consumed before work, combined with IV (SLIV) and 4) a portable battery-operated water-perfused suit (WPS). Mean with 95% confidence intervals are presented. RESULTS Tolerance time was extended in PCM (46 [36, 56] min, P = 0.018), SLIV (56 [46, 67] min, P  less then  0.001) and WPS (62 [53, 70] min, P  less then  0.001), compared with control (39 [30, 48] min). Tolerance time was longer in SLIV and WPS compared with both IV (48 [39, 58 min]) and PCM (P ≤ 0.011). After 20 min of work, HR was lower in SLIV (121 [105, 136] beats·min-1), WPS (117 [101, 133] beats·min-1) and IV (130 [116, 143] beats·min-1) compared with control (137 [120, 155] beats·min-1) (all P  less then  0.001). PCM (133 [116, 151] beats·min-1) did not differ from control. CONCLUSION All cooling methods, except PCM, utilised in the present study reduced cardiovascular strain, while SLIV and WPS are most likely to extend tolerance time for those working in the heat dressed in a Class 2 CBRN ensemble. Technological developments present diverse opportunities to modernise services for the rail industry. Systems can be implemented to improve passengers' experiences, but these may also affect the experiences of crew working on board trains. This first-of-a-kind research extends the concept of customer journey mapping as a design tool to understand the experiences of train crew. To produce these crew journey maps, interviews and user observation methods were adopted (N = 22). Results show that two main negative touchpoints for the crew occur at the platform-train interface and during revenue protection activities. This paper presents an innovative methodological contribution around journey mapping to better understand rail experiences, but revolving around the crew rather than the expected consumer experience. We conclude this paper proposing requirements for technological systems and indicate opportunities for the design of systems to generate human-centred improvements for the working practices and experiences of train crew. Many factors affect the comfort of automotive seats including pressure distribution, vibration, temperature, and backrest inclination. However, one aspect of seating that has not been well studied is leg splay; splay is a rotation at the hips which causes the knees to move outward. The work presented here identified the ranges of "comfortable" splay in different styles of seats and related changes in seating pressure due to leg splay. Sixteen midsized male participants were tested in six seats a flat control, three mid-sized sedan, a sports car, and a pickup truck. Participants sat with two leg conditions 1) shoulder width apart and 2) rotating their legs to splay to a self-identified, comfortable position. For each test, the participant placed his left leg on a foot support and right leg on a depressible pedal to mimic a driving position. In each posture, leg angle and seat pan pressures were collected. Of the seats tested, the flat wooden seat had the highest possible splay (24.5°). The three sedan seats had similar splay angles (16.