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We demonstrate room temperature operation of mid-wave infrared photodetectors leveraging a guided mode resonance architecture and bulk alloy InAsSb absorbers. Room temperature operation with low dark current is achieved by using detector structures with ultra-thin (150 , 250 nm) absorbers leveraging the strong confinement enabled by the guided mode architecture. Devices with 1D and 2D grating arrays are fabricated and characterized, and compared to unpatterned detector devices. We see enhancement in the detectors' optical response associated with coupling to both TE- and TM-polarized guided modes and good agreement between experimental and theoretically-predicted behavior. We show strong enhancement for unpolarized light incident on 2D grating arrays, with a broader spectral response than observed for polarized light incident upon 1D grating GMR detectors. The bulk InAsSb detectors presented in this work offer enhanced performance at room temperature for a range of imaging and sensing applications. [ABSTRACT FROM AUTHOR]

Link analysis (LA) is a popular ergonomic tool for studying and improving the layout of workspaces. It uses a data (event) recording method to input interactions of human behavior with their environment. The traditional 'pen and paper'' method of LA is cumbersome, time consuming, and gives limited outputs. To address these limitations, the computerized link analysis (CLA) system was developed and tested in laboratory and real-world environments. CLA offers an integrated task analysis tool, including traditional LA functions (layout, event recording) with more detail for operator activities, time-motion functions, and multioperator data recording. As well as the conventional LA results (link diagrams and link tables), there are additional outputs for time-event lists (start/end time, duration, chronology, additional notes, importance, and operator ID), and processed link diagrams with the link direction and frequency. © 2012 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Objective: To examine the chronic illness literature and evaluate the impact on single parenting and children and adolescents with chronic illness.Methods: We conducted literature reviews of relevant research pertaining to single-parent families on PubMed, Medline, and PsychINFO and also surveyed pertinent book chapters and all of the articles from the Journal of Pediatric Psychology since 1987 for articles, specifically examining the potential associations of single (lone) parenting versus two-parent households on children's psychosocial functioning and the impact of the child's illness on caregiver functioning.Results: While the literature has examined and discussed the stressors associated with parenting a child with an illness, including the impact of illness on finances, family roles, and caregiver burden, few studies have examined single parents of children and adolescents with chronic illnesses and related stressors stemming from being a lone caregiver.Conclusions: There is a dearth of studies examining the association between lone parenting and psychosocial functioning among children and adolescents with chronic illnesses. Specific questions necessitating future investigation are summarized and recommendations are made for future research in this important area of inquiry. [ABSTRACT FROM AUTHOR]

The effect of variations in posture and vibration magnitude on apparent mass and seat-to-pelvis pitch transmissibility have been studied with vertical random vibration over the frequency range 1·0–20 Hz. Each of 12 subjects was exposed to 27 combinations of three vibration magnitudes (0·2, 1·0 and 2·0m/s2 r.m.s.) and nine sitting postures (“upright”, “anterior lean”, “posterior lean”, “kyphotic”, “back-on”, “pelvis support”, “inverted SIT-BAR” (increased pressure beneath ischial tuberosities), “bead cushion” (decreased pressure beneath ischial tuberosities) and “belt” (wearing an elasticated belt)).Peaks in the apparent masses were observed at about 5 and 10 Hz, and in the seat-to-pelvis pitch transmissibilities at about 12 Hz. In all postures, the resonance frequencies in the apparent mass and transmissibility decreased with increased vibration magnitude, indicating a non-linear softening system. There were only small changes in apparent mass or transmissibility with posture, although peaks were lower for the apparent mass in the “kyphotic” posture and were lower for the transmissibility in the “belt” posture. The changes in apparent mass and transmissibility caused by changes in vibration magnitude were greater than the changes caused by variation in posture. [Copyright &y& Elsevier]

A subjective quality test was undertaken to quantify the amount by which the perceived quality of full-face digital video (such as a newsreader) varies with the spatial location of degradation. It was found that perceived error was greatest for degradation occurring around the eyes and mouth. Traditional digital video assessment techniques, such as peak signal-to-noise ratio, rate all errors equally, irrespective of spatial location and thus do not give a meaningful measure of perceived quality. [ABSTRACT FROM AUTHOR]

Reductions in vehicle vibration that may contribute to improvements in overall vehicle ride could individually be too small to be detected by drivers or passengers. This study investigated the 'difference threshold' (the difference in magnitude between two stimuli which is just sufficient for their difference to be detected) required for a change in vehicle ride to be perceived and whether this was consistent with Weber's Law. Ten male and 10 female subjects sat in a car seat and were exposed to four different reproductions of the vertical vibration recorded on the seat of a car. Three of the stimuli had the same waveform recorded while the car traversed a tarmac surface. This waveform was reproduced using three different magnitudes of vibration at the seat: 0.2, 0.4 and 0.8 m s(-2) r.m.s. (Wb weighted). The other stimulus was recorded with the car traversing a 'pavé' surface that gave a different waveform that was reproduced at a magnitude of 0.4 m s(-2) r.m.s. (Wb weighted). There were significant differences in the absolute difference thresholds measured using the same waveform at the three different magnitudes. When the difference thresholds were expressed in relative terms (the proportion by which two stimuli must differ in magnitude to be discriminated), the relative difference thresholds were approximately 13%, and independent of both the vibration magnitude and the vibration waveform. The results are therefore consistent with Weber's Law. No consistent differences were observed between the responses of male and female subjects. [ABSTRACT FROM AUTHOR]

Background: A quantitative comfort model will aid in evaluating comfort levels of various target groups before the actual flight of an airplane. However, constructing the model is always a challenge due to the complexity of the phenomenon., Objectives: In this paper, we present quantitative comfort models to predict the (dis)comfort of passengers flying with turboprops based on objective measures., Methods: Ninety-seven participants took part in two experiments conducted during real flights, during which forty of them had environmental and personal factors recorded using (self-developed) measurement tools. The collected data were analyzed to model the relations between objective measures and subjective feelings., Results: Two preliminary models based on gradient boosting regression were developed. The models were able to predict the changes in comfort and discomfort of individual passengers with an accuracy of 0.12±0.01 and 0.21±0.01 regarding normalized comfort and discomfort scores, respectively. Additionally, contributions of different factors were highlighted., Conclusion: The outcomes of the models show that we took a step forward in modeling the human comfort experience using objective measurements. Anthropometry (including age), seat positions, time duration, and row (noise) emerged as leading factors influencing the feeling of (dis)comfort in turboprop planes.

We present a spectrally selective, passively cooled mid-wave infrared bolometric absorber engineered to spatially and spectrally decouple infrared absorption and thermal emission. The structure leverages an antenna-coupled metal-insulator-metal resonance for mid-wave infrared normal incidence photon absorption and a long-wave infrared optical phonon absorption feature, aligned closer to peak room temperature thermal emission. The phonon-mediated resonant absorption enables a strong long-wave infrared thermal emission feature limited to grazing angles, leaving the mid-wave infrared absorption feature undisturbed. The two independently controlled absorption/emission phenomena demonstrate decoupling of the photon detection mechanism from radiative cooling and offer a new design approach enabling ultra-thin, passively cooled mid-wave infrared bolometers.

Objective: Analyze the effect of sodium supplementation, hydration, and climate on dysnatremia in ultramarathon runners., Design: Prospective observational study., Setting: The 2017 80 km (50 mile) stage of the 250 km (150 mile) 6-stage RacingThePlanet ultramarathon in 2017 Chilean, Patagonian, and 2018 Namibian, Mongolian, and Chilean deserts., Participants: All race entrants who could understand English were invited to participate, with 266 runners enrolled, mean age of 43 years (± 9), 61 (36%) females, average weight 74 kg (± 12.5), and average race time 14.5 (± 4.1) hours. Post-race sodium collected on 174 (74%) and 164 (62%) participants with both the blood sample and post-race questionnaire., Intervention: Weight change and finish line serum sodium levels were gathered., Main Outcome Measures: Incidence of exercise-associated hyponatremia (EAH; <135 mmol·L-1) and hypernatremia (>145 mmol·L-1) by sodium ingestion and climate., Results: Eleven (6.3%) runners developed EAH, and 30 (17.2%) developed hypernatremia. Those with EAH were 14 kg heavier at baseline, had significantly less training distances, and averaged 5 to 6 hours longer to cover 50 miles (80 km) than the other participants. Neither rate nor total ingested supplemental sodium was correlated with dysnatremia, without significant differences in drinking behaviors or type of supplement compared with normonatremic runners. Hypernatremic runners were more often dehydrated [8 (28%), -4.7 kg (± 9.8)] than EAH [4 (14%), -1.1 kg (± 3.8)] (P < 0.01), and EAH runners were more frequently overhydrated (6, 67%) than hypernatremia (1, 11%) (P < 0.01). In the 98 (56%) runners from hot races, there was EAH OR = 3.5 [95% confidence interval (CI), 0.9-25.9] and hypernatremia OR = 8.8 (95% CI, 2.9-39.5) compared with cold races., Conclusions: This was the first study to show that hot race climates are an independent risk factor for EAH and hypernatremia. Sodium supplementation did not prevent EAH nor cause hypernatremia. Longer training distances, lower body mass, and avoidance of overhydration were shown to be the most important factors to prevent EAH and avoidance of dehydration to prevent hypernatremia., Competing Interests: The authors report no conflicts of interest., (Copyright © 2020 Wolters Kluwer Health, Inc. All rights reserved.)

Polyurethane foams have unique properties that make them suitable for a wide range of applications, including cushioning and seat pads. The foam mechanical properties largely depend on both the parent material and foam cell microstructure. Uniaxial loading experiments, X-ray tomography and finite element analysis can be used to investigate the relationship between the macroscopic mechanical properties and microscopic foam structure. Polyurethane foam specimens were scanned using X-ray computed tomography. The scanned geometries were converted to three-dimensional (3D) CAD models using open source, and commercially available CAD software tools. The models were meshed and used to simulate the compression tests using the implicit finite element method. The calculated uniaxial compression tests were in good agreement with experimental results for strains up to 30%. The presented method would be effective in investigating the effect of polymer foam geometrical features in macroscopic mechanical properties, and guide manufacturing methods for specific applications.