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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 Ref index 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 Ref and THL heat strain indexes as dual metrics for characterizing the heat strain performance of turnout clothing fabrics. [ABSTRACT FROM AUTHOR]

Aim: To compare the effects of a supported speed treadmill training exercise program (SSTTEP) with exercise on spasticity, strength, motor control, gait spatiotemporal parameters, gross motor skills, and physical function. Method: Twenty-six children (14 males, 12 females; mean age 9y 6mo, SD 2y 2mo) with spastic cerebral palsy (CP; diplegia, n = 12; triplegia, n = 2; quadriplegia n = 12; Gross Motor Function Classification System levels II-IV) were randomly assigned to the SSTTEP or exercise (strengthening) group. After a twice daily, 2 week induction, children continued the intervention at home 5 days a week for 10 weeks. Data collected at baseline, after 12-weeks' intervention, and 4 weeks after the intervention stopped included spasticity, motor control, and strength; gait spatiotemporal parameters; Gross Motor Function Measure (GMFM); and Pediatric Outcomes Data Collection Instrument (PODCI). Results: Gait speed, cadence, and PODCI global scores improved, with no difference between groups. No significant changes were seen in spasticity, strength, motor control, GMFM scores, or PODCI transfers and mobility. Post-hoc testing showed that gains in gait speed and PODCI global scores were maintained in the SSTTEP group after withdrawal of the intervention. Interpretation: Although our hypothesis that the SSTTEP group would have better outcomes was not supported, results are encouraging as children in both groups showed changes in function and gait. Only the SSTTEP group maintained gains after withdrawal of intervention.

An ideal firefighter turnout system should be capable of releasing body heat to prevent heat stress, indicated by THL (total heat loss) and Ref (evaporative resistance) indexes, while maintaining high thermal protective performance (TPP). Our study found no correlations between THL and Ref, or between Ref and TPP. The results showed that, when tested in the mild condition as in the standard THL test method, turnout systems with bi-component moisture barriers exhibited an advantage in THL that did not translate to more thermally stressful hot environments. A physiological manikin was used to understand the effect of turnout clothing systems on heat strain in different environmental conditions and the value of utilizing Ref or THL to predict heat strain performance. We found no difference in heat strain performance between composites with one-layer and two-layer spunlace thermal liners in mild or hot conditions. It showed that both THL and Ref had their limitations: THL only predicted thermal burden in mild environments, while Ref was only correlated in hot conditions. Thus, the exclusive reliance on either index could increase the risk of heat stress, and we recommend incorporating the Ref heat strain index, along with THL, as dual metrics for certifying the heat strain performance of turnout suits in the NFPA 1971 standard. [ABSTRACT FROM AUTHOR]

Firefighters frequently have to work in direct solar radiant heat. To reduce firefighter heat stress, the influence of turnout garment properties on heat gain from solar radiation must be understood. This research studied the effects of color, texture, washing, and contamination of outer shell fabrics on heat loss through firefighter turnout fabric materials in simulated solar exposures. It showed that solar radiation could be a major factor in heat loss through turnout suits. Solar radiation equivalent to a sunny day completely reversed heat exchange through the turnout fabric systems, converting a heat loss of about 240 W/m2 to a heat gain exceeding 100 W/m2. Solar radiation caused turnout fabric systems to dry out and this decreased the performance of turnout systems that incorporated bi-component moisture barriers. Most significantly, the color of the outer shell had a major influence on lowering turnout heat loss in solar exposures. Composites with a black-dyed outer shell absorbed more solar energy than composites with lighter colored shell materials. Soot and fire-ground contaminants present on turnout outer shell fabrics also reduced heat loss under solar exposure. The findings of this study answered long-standing questions about the importance of turnout fabric color on heat exchange with the environment. The results provide additional motivation for efficient turnout cleaning practices, not only to reduce potentially toxic exposure to smoke contaminants, but to reduce turnout-gear-related heat strain on firefighters. [ABSTRACT FROM AUTHOR]

The goal of this research was to understand how firefighter protective suits perform in different operational environments. This study used a sweating guarded hotplate to examine the effect of environmental temperature (20–45°C) and relative humidity (25–85% RH) on evaporative heat loss through firefighter turnout materials. Four firefighter turnout composites containing three different bi-component (semi-permeable) and one microporous moisture barriers were selected. The results showed that the evaporative resistance of microporous moisture barrier systems was independent of environmental testing conditions. However, absorbed moisture strongly affected evaporative heat loss through semi-permeable moisture barriers coated with a layer of nonporous hydrophilic polymer. Moisture absorption in mild environment (20–25°C) tests, or when testing at high humidity (>85% RH), significantly increased water vapor transmission in semi-permeable turnout systems. It was also found that environmental conditions used in the total heat loss (THL) test (25°C and 65% RH) produced moisture condensation in bi-component barrier systems, making them appear more breathable than could be expected when worn in hotter environments. Regression models successfully qualified the relationships between moisture uptake levels in semi-permeable barrier systems and evaporative resistance and THL. These findings reveal the limitations in relying on THL, the heat strain index currently called for by the NFPA 1971 Standard for Structural Firefighter personal protective equipment, and supports the need to measure turnout evaporative resistance at 35°C (Ret), in addition to THL at 25°C. [ABSTRACT FROM AUTHOR]

Byline: Sandra Bellamy, Heather Worden, See Yang, Kyle Watson 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.

Herein two new and concise synthetic approaches for making an unsaturated bicyclic oxamazin core are reported. The first involves the use of an intramolecular Diels–Alder reaction to form both of the fused rings in one step. The second approach incorporates ring-closing olefin metathesis in the final step to form the second fused ring of the core. The scope of the second approach was also expanded further to afford larger ringed bicyclic systems. [ABSTRACT FROM AUTHOR]

Abstract: The use of fluorine as an oxidizing agent in aluminum (Al)-based thermite reactions yields higher peak pressures and an increase in gas production compared with oxygen-containing oxidizers, such as molybdenum trioxide (MoO3). Thus fluorination reactions have the potential to excel in situations that require high pressures and flame speeds. This study compares the combustion behaviors of Al/Teflon, Al/MoO3/Teflon, and Al/MoO3 in an effort to determine the effects that the replacement of oxygen with fluorine has on the reaction dynamics in both open and confined burning configurations. Data were collected from pressure sensors and high-speed imaging. The mass percent of Al was varied from 10 to 90% to study the effects of composition. The composites were then further tested at the optimum stoichiometry using either 50 nm or 1–3 μm Al to examine the effect of Al particle size. The addition of Teflon in an open configuration hinders the reaction due to a loss of liberated gas. Confining the reaction enables the trapped gases to enhance convection, yielding increased flame speeds. For confined conditions, the reactions containing Teflon exhibit higher peak pressures but lower flame speeds than the reactions with MoO3. These results imply that a direct relationship between generated gas pressures and flame speeds does not generally exist when comparing different oxidizers. The theoretically predicted relationship for the relative flame speed versus relative particle size based on the melt-dispersion mechanism agrees with experimental data for all Al particle sizes and for the fluorination reaction. Particle synthesis parameters are suggested that could be controlled to enable micrometer-scale Al particles to achieve the performance of nanoscale Al particles. This is of significant practical importance, because nanoparticles are 30 to 50 times more expensive than the micrometer particles. [Copyright &y& Elsevier]

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. [ABSTRACT FROM AUTHOR]

The theoretically predicted relationship for the relative flame rate versus relative particle size based on the melt dispersion mechanism (MDM), which was previously confirmed for oxidation of 40–120 nm diameter aluminum particles, is found to be in agreement with experiments for 1–3 μm diameter Al particles and fluorination. The main physical parameters for MDM (pressure in molten particle, cavitation threshold, and nanoclusters’ velocity) have been estimated for micron scale particles. The results suggest parameters that could be controlled during particle synthesis that would enable micron scale Al particles to react and achieve the performance of nanoscale Al particles. [ABSTRACT FROM AUTHOR]

The successful approach to bicyclic oxamazins (III) relies on a Mitsunobu reaction to form β-lactams (II) selectively, followed by a ring closing metathesis (RCM). [ABSTRACT FROM AUTHOR]

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.

Manikins have been used for almost 100 years to help understand the properties of clothing materials and garments. Data from sweating manikins also have been used within thermoregulation computer models to estimate the physiological responses of humans. In recent years, the development of the ManikinPC system has incorporated a thermoregulation model into a thermal sweating manikin system to provide a real-time analysis of predicted physiological response. This paper describes an experimental study that demonstrates the utility of this manikin-model system to predict the effects of three composite materials used in firefighter suits on human physiological response. This study addresses this question: Can ManikinPC emulate the physiological response of a controlled wear trial using three different sets of firefighter turnout gear in one environmental condition? The average core temperature, skin temperature, and sweat loss from human subjects are compared with the predicted values generated from the manikin coupled with the model. Results indicate similar trends and ranking of the three suits. The data revealed slightly higher predictive responses from the manikin-model system compared with the collected human data.

Purpose: 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)., Methods: After training in cognitive interviewing techniques, investigators defined item intent and developed questions for each item. Parents of children with CP (n = 27) participated in interviews probing item meaning, item wording, and response choice adequacy and appropriateness., Results: Qualitative analysis identified 3 themes: item clarity; relevance, context, and attribution; and problems with wording or tone. Parents reported the importance of delineating task components, assistance amount, and environmental context., Conclusion: Cognitive interviewing provided valuable information about the validity of new items and insight to improve relevance and context. We believe that the development of CATs in pediatric rehabilitation may ultimately reduce the impact of the issues identified.

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.