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A validated physiological manikin method was used to qualify environmentally dependent correlations between firefighter turnout total heat loss (THL) and intrinsic evaporative resistance (Ref) heat strain indexes and core temperature rise in stressful work conducted in mild (25 °C, 65% relative humidity [RH]) and hot (35 °C, 40% RH; 40 °C, 28% RH) conditions. Five turnout suit constructions representing a wide range of breathability were selected. The observed correlations between measured material heat loss and core temperature showed that the THL heat strain index accurately forecast thermal burden in mild environments (<25 °C); while the Refindex provided accurate prediction in hot environments (>35 °C). They showed that the THL index did not predict heat strain in hot work environments. The findings of this study support incorporating both the Refand THL heat strain indexes as dual metrics for characterizing the heat strain performance of turnout clothing fabrics.

Compact beam steering in the visible spectral range is required for a wide range of emerging applications, such as augmented and virtual reality displays, optical traps for quantum information processing, biological sensing, and stimulation. Optical phased arrays (OPAs) can shape and steer light to enable these applications with no moving parts on a compact chip. However, OPA demonstrations have been mainly limited to the near-infrared spectral range due to the fabrication and material challenges imposed by the shorter wavelengths. Here, we demonstrate the first chip-scale phased array operating at blue wavelengths (488 nm) using a high-confinement silicon nitride platform. We use a sparse aperiodic emitter layout to mitigate fabrication constraints at this short wavelength and achieve wide-angle beam steering over a 50° field of view with a full width at half-maximum beam size of 0.17°. Large-scale integration of this platform paves the way for fully reconfigurable chip-scale three-dimensional volumetric light projection across the entire visible range.

The purpose of this study was to assess the concurrent validity and reliability of scores from 4 new parent-report computer-adapted testing (CAT) programs developed to measure the physical functioning of children with cerebral palsy (CP). The Shriners Hospitals for Children CP-CAT battery includes upper-extremity skills, lower-extremity and mobility skills, activity, and global physical health.

The pairing of healthcare practitioners with engineers can produce products to revolutionise patient care. This paper discusses benefits of a novel-design ambulatory assistive device to promote gait efficiency and safety in adult individuals with balance disorders. Posterior-wheeled walkers are commonly used and reported in paediatric research literature to promote increased walking speed and decreased energy demand, when compared to anterior-wheeled walkers. Posterior walkers are not commonly utilised for adults in the USA, likely, due to limited commercial availability and problems with size and function of current designs. This paper reports a new equipment design for an adult posterior-wheeled walker with features that promote optimal skeletal alignment, allow normal stride length, and provide protection against backward and lateral falls, while reducing mechanical vibration within the device itself. Additional features enhance ease of storage, transport, and aesthetics.

Background:Contemporary clinical assessments of activity are needed across the age span for children with cerebral palsy (CP). Computerized adaptive testing (CAT) has the potential to efficiently administer items for children across wide age spans and functional levels.Objective:The objective of this study was to examine the psychometric properties of a new item bank and simulated computerized adaptive test to assess activity level abilities in children with CP.Design:This was a cross-sectional item calibration study.Methods:The convenience sample consisted of 308 children and youth with CP, aged 2 to 20 years (X=10.7, SD=4.0), recruited from 4 pediatric hospitals. We collected parent-report data on an initial set of 45 activity items. Using an Item Response Theory (IRT) approach, we compared estimated scores from the activity item bank with concurrent instruments, examined discriminate validity, and developed computer simulations of a CAT algorithm with multiple stop rules to evaluate scale coverage, score agreement with CAT algorithms, and discriminant and concurrent validity.Results:Confirmatory factor analysis supported scale unidimensionality, local item dependence, and invariance. Scores from the computer simulations of the prototype CATs with varying stop rules were consistent with scores from the full item bank (r=.93–.98). The activity summary scores discriminated across levels of upper-extremity and gross motor severity and were correlated with the Pediatric Outcomes Data Collection Instrument (PODCI) physical function and sports subscale (r=.86), the Functional Independence Measure for Children (Wee-FIM) (r=.79), and the Pediatric Quality of Life Inventory–Cerebral Palsy version (r=.74).Limitations:The sample size was small for such IRT item banks and CAT development studies. Another limitation was oversampling of children with CP at higher functioning levels.Conclusions:The new activity item bank appears to have promise for use in a CAT application for the assessment of activity abilities in children with CP across a wide age range and different levels of motor severity.

The purpose of this study was to assess the content, format, and comprehension of test items and responses developed for use in a computer adaptive test (CAT) of physical function for children with cerebral palsy (CP).

The purposes of this paper are to: 1) present a conceptual framework that supports development of a computer adaptive test (CAT) outcome measure of physical functioning for children with cerebral palsy; 2) illustrate the development and refinement of an item bank for use in the CAT; and 3) describe the intended application of these newly developed items in a CAT platform. Improvement in physical functioning is one of the most important developmental and rehabilitative outcomes for children with cerebral palsy (CP). Computer adaptive testing technology provides means to improve outcome measures. We adopted a conceptual framework appropriate to support a CAT of physical functioning consisting of 4 sub-domains: lower extremity skills, upper extremity skills, physical activity, and global physical health. Review of existing tests and measures of physical function, expert clinician review, and cognitive testing were used to identify, develop and refine sets of items (item banks) that reflect the breadth of each sub-domain. These item banks will be used to develop contemporary parent-report instruments by application of Item Response Theory (IRT) analyses, leading to a CAT outcome measure. Such CAT approaches can efficiently assess broad areas of physical functioning across a wide age-range and levels of severity of children with CP.

The turbulence filter and the proper orthogonal decomposition (POD)methods are applied to PIV measurements of lifted CH4-air diffusionflames at three different Reynolds numbers. Properties such as vorticityand strain rate distributions of the decomposed fields are analyzed inorder to assess the physical behavior. The turbulence filter can userelatively less data than the POD method while still providingsignificant insight about the flow field. The energy activation ratesshow the first modes (mean flow) account for 85% of the total energy.Reconstruction of the POD modes reveals that the combination of modesyields a complex fluctuating behavior. The averaged Reynolds stress ofthe mean flow removed parts shows interesting correlation with the meanflow vorticity and strain rate distributions. Selected turbulentproperties are calculated and discussed.

This paper presents the results of a parametric study concerning the phenomenon of liftoff of a nonpremixed jet flame. The dependence of liftoff height on jet exit velocity and coflow velocity is described. It is shown that lifted flames become less sensitive to jet exit velocity as the stabilization point recedes from the burner exit. The results reveal that in cases of extreme liftoff height, increases in jet exit velocity with a constant coflow cause some ethylene flames to stabilize closer to the burner. The success of current theories on lifted flame stabilization in comparison to the experimental results of this study are assessed. The existence of multiple regimes for flame stabilization, incorporating aspects of both premixed and nonpremixed combustion, is proposed.