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The complex Al/CuO self-propagating reaction involving multi-phase and multi-species dynamics was studied in order to investigate the very high flame temperature around the vaporization temperature of alumina, even under a neutral environment. Experiments were performed on different sputter-deposited Al/CuO multilayers coupling optical spectroscopy with high speed camera measurements. The clear presence of both AlO and Al signatures in gas phase suggests that the redox reaction starts in the bulk nanolaminate, which then rapidly tear off the substrate to continue burning in a heterogeneous (condensed and gas) phase in the environment. The flame temperature increases with the stoichiometry but is independent of the bilayer thickness. In addition to the confirmation of the effects of stoichiometry and the bilayer thickness on the characteristics of the self-propagating reaction, the predominant role of process-induced residual stress was highlighted for the first time; it can lead to an early disruption of the multilayer long before the completion of the redox reaction. [ABSTRACT FROM AUTHOR]

Aim Providing consistent levels of oxygen saturation (SpO2) for infants in neonatal intensive care units is not easy. This study explored how effectively the Auto-Mixer® algorithm automatically adjusted fraction of inspired oxygen (FiO2) levels to maintain SpO2 within an intended range in extremely low birth weight infants receiving supplemental oxygen without mechanical ventilation. Methods Twenty extremely low birth weight infants were randomly assigned to the Auto-Mixer® group or the manual intervention group and studied for 12 h. The SpO2 target was 85-93%, and the outcomes were the percentage of time SpO2 was within target, SpO2 variability, SpO2 >95%, oxygen received and manual interventions. Results The percentage of time within intended SpO2 was 58 ± 4% in the Auto-Mixer® group and 33.7 ± 4.7% in the manual group, SpO2 >95% was 26.5% vs 54.8%, average SpO2 and FiO2 were 89.8% vs 92.2% and 37% vs 44.1%, and manual interventions were 0 vs 80 (p < 0.05). Brief periods of SpO2 < 85% occurred more frequently in the Auto-Mixer® group. Conclusion The Auto-Mixer® effectively increased the percentage of time that SpO2 was within the intended target range and decreased the time with high SpO2 in spontaneously breathing extremely low birth weight infants receiving supplemental oxygen. [ABSTRACT FROM AUTHOR]

Thermite multilayered films have the potential to be used as local high intensity heat sources for a variety of applications. Improving the ability of researchers to more rapidly develop Micro Electro Mechanical Systems devices based on thermite multilayer films requires predictive modeling in which an understanding of the relationship between the properties (ignition and flame propagation), the multilayer structure and composition (bilayer thicknesses, ratio of reactants, and nature of interfaces), and aspects related to integration (substrate conductivity and ignition apparatus) is achieved. Assembling all these aspects, this work proposes an original 2D diffusion-reaction modeling framework to predict the ignition threshold and reaction dynamics of Al/CuO multilayered thin films. This model takes into consideration that CuO first decomposes into Cu2O, and then, released oxygen diffuses across the Cu2O and Al2 O3 layers before reacting with pure Al to form Al2O3. This model is experimentally validated from ignition and flame velocity data acquired on Al/CuO multilayers deposited on a Kapton layer. This paper discusses, for the first time, the importance of determining the ceiling temperature above which the multilayers disintegrate, possibly before their complete combustion, thus severely impacting the reaction front velocity and energy release. This work provides a set of heating surface areas to obtain the best ignition conditions, i.e., with minimal ignition power, as a function of the substrate type. [ABSTRACT FROM AUTHOR]

Introduction: Although the efficacy of monotherapy with biologics for psoriasis is well established, many patients fail to achieve complete plaque clearance from their initial biologic treatment alone. Adjunctive treatment with topical calcipotriene plus betamethasone dipropionate (Cal/BD) foam may offer substantial clinical benefit and potential cost savings. Methods: We conducted a 16-week, open-label, single-arm study of adjunctive therapy with Cal/BD foam in subjects who had been treated with etanercept or adalimumab for ≥ 24 weeks but had not obtained a satisfactory treatment response. Assessments included affected body surface area (BSA), Physician's Global Assessment (PGA) of disease severity, BSA × PGA, National Psoriasis Foundation (NPF) Treat to Target status, and likelihood of the physician to switch biologics. In parallel, a cost analysis was performed to compare the cost of switching to a different biologic versus adding Cal/BD foam to the original biologic. Results: Four weeks of daily adjunctive treatment with Cal/BD foam led to notable reductions in BSA, PGA, and BSA × PGA relative to baseline. Additionally, by week 4, > 75% of subjects achieved NPF Treat to Target status, and the likelihood of the investigator to switch biologics decreased from 90.0% at baseline to 7.1%. The improved efficacy was maintained throughout the additional 12 weeks of maintenance Cal/BD foam application. The pharmacoeconomic evaluation demonstrated that adjuvant use of Cal/BD foam led to cost savings compared with switching biologic treatments. Limitations: Due to the nature of the open-label study lacking a vehicle-treated control, no statistical comparison can be made. Conclusions: The results of this study demonstrate that the addition of Cal/BD foam to plaque psoriasis patients who still have significant disease activity despite being on stable biologic therapy improves treatment outcomes to the point where switching to a more expensive biologic therapy is a less suitable treatment option. [ABSTRACT FROM AUTHOR]

We have developeda new method to study the oxygen surface exchangekinetics in oxide materials in the form of epitaxial thin films byanalyzing subtle cell parameter variations induced by changes in theoxygen stoichiometry of the material. The method consists of continuouslyanalyzing the X-ray diffraction pattern of particular film reflectionswith a linear X-ray fast detector in a static position, while exposingthe sample to sudden changes in the pO2of the atmosphere at elevated temperatures. With this method, wehave been able to follow cell parameter changes as small as 2.10–4Å in time intervals as short as 10 s in La2NiO4+δepitaxial films and La2NiO4+δ/LaNiO3−δbilayers.This method provides a simpler and contactless tool for dynamicallyanalyzing oxygen surface exchange kinetics and diffusion in transitionmetal oxide compounds, and complements other currently used techniquessuch as Electric Conductivity Relaxation (ECR) and Isotopic Exchangedepth profiling (IEDP). In addition, this method is a unique toolto address oxygen transport across solid–solid interfaces inthin film heterostructures. [ABSTRACT FROM AUTHOR]