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Uncontrolled hemorrhage models require sufficient quantities of donor blood products to support resuscitation. To that end, we describe a novel method of whole blood extraction from donor swine using resuscitative endovascular balloon occlusion of the aorta (REBOA) to support hemodynamics during terminal blood extraction and its impact on the quality of banked blood. Ten adult Yorkshire-cross swine were anesthetized and instrumented with an REBOA catheter, femoral multistage venous cannula, and proximal/distal blood pressure monitoring. Hemodynamics during terminal blood extraction was supported with hand-titrated partial REBOA. Blood samples were taken at set time points for analysis. The median collected blood volume was 3912 mL, with all animals surviving through the planned blood collection of 60% estimated total blood volume (ETBV). Median lactate and potassium levels remained within normal limits for swine through collection of 40% of the ETBV. Median hemoglobin through collection of 40% ETBV did not significantly change from values measured at the start of hemorrhage. This method of whole blood extraction provided sufficient blood volume and blood quality appropriate for transfusion through 40% ETBV, with remaining collected blood likely still acceptable for allogeneic transfusion despite increased lactate levels. This method of whole blood extraction can efficiently provide a large volume of quality blood to support resuscitation for subsequent uncontrolled hemorrhage models. [ABSTRACT FROM AUTHOR]

Nonradiative centers in InAs dots grown on GaAs substrates are investigated in this study. The emission from InAs dots close to 1.3 μm is monitored under different excitation densities and different excitation energy. The used samples were also treated by hydrogen plasma in order to suppress the nonradiative centers. The purpose of this work is to study how nonradiative centers influence the efficiency of InAs dots emission and whether the nonradiative centers can be reduced. Our results clearly illustrate that there indeed exist nonradiative centers, both at the interface between the InAs dots and surrounding layers and in the GaAs layers, which can be suppressed by H-treatments. A technique to estimate relative amount of nonradiative centers is also discussed. [Copyright &y& Elsevier]

Effect of temperature and time of heat treatment on the distribution of ion-implanted nitrogen in poly Si0.65Ge0.35 gate MOS samples was studied. Secondary ion mass spectrometry (SIMS) was used for the qualitative analysis of the nitrogen distribution. Rapid thermal processing was carried out for a temperature range of 950–1070°C for the redistribution of ions. The nitrogen implantation doses were 5×1014 cm−2, 2×1015 cm−2 and 5×1015 cm−2, all with an implantation energy of 50 keV. For a uniform distribution of nitrogen in the SiO2 region, an optimal temperature at a well calibrated time must be applied and this depends on the implantation dose. For medium and high concentrations the optimal conditions were 1050°C and 15 s, and 1070°C and 15 s, respectively. A uniform nitrogen distribution could be obtained throughout the SiO2 film. Prolonged heat treatment can cause degradation of the oxide layer and movement of the nitrogen and oxygen into the channel and the poly-Si0.65Ge0.35 layer. [Copyright &y& Elsevier]

We explore the occurrence of dust in M-type Mira atmospheres and its effect on limb darkening under schematic assumptions about dust temperatures and dust particle properties. Dust particles that are thermodynamically coupled to the surrounding gas may form and may affect limb darkening, though only by very little in infrared continuum bandpasses. Dust particles that assume the equilibrium temperature given by the mean intensity of the radiation field only form under rare circumstances. Unexpectedly large or wavelength-dependent infrared continuum radii observed by interferometry are unlikely to be caused by atmospheric dust, except possibly near 1 μm; however, radius measurements may be significantly affected by molecular band contamination. [ABSTRACT FROM AUTHOR]

We discuss the wavelength dependence of angular diameters of M giants from an observational perspective. Observers cannot directly measure an optical-depth radius for a star, despite this being a common theoretical definition. Instead, they can use an interferometer to measure the square of the fringe visibility. We present new plots of the wavelength-dependent centre-to-limb variation (CLV) of intensity of the stellar disc as well as visibility for Mira and non-Mira M giant models. We use the terms ‘CLV spectra’ and ‘visibility spectra’ for these plots. We discuss a model-predicted extreme limb-darkening effect (also called the narrow-bright-core effect) in very strong TiO bands which can lead to a misinterpretation of the size of a star in these bands. We find no evidence as yet that this effect occurs in real stars. Our CLV spectra can explain the similarity in visibilities of R Dor (M8IIIe) that have been observed recently, despite the use of two different passbands. We compare several observations with models, and find that the models generally underestimate the observed variation in visibility with wavelength. We present CLV and visibility spectra for a model that is applicable to the M supergiant α Ori. [ABSTRACT FROM AUTHOR]

Current-Voltage characteristics of Zigzag and Armchair Graphene Nanoribbons before and after H 2 S adsorption. • DFT analysis of zigzag and armchair GNR as H 2 S gas sensing element. • Electronic transport properties have been analysed as sensing parameters. • Adsorption process found exothermic and H 2 S physisorbed to Z/A GNR, defends its reusable property. • H 2 S gas sensitivity of ZGNRs is better than Armchair GNR, however suffers in recovery time. Armchair (A) and zigzag (Z) type graphene nanoribbons (GNR) have been investigated for its suitability to sense the toxic H 2 S gas, by using density functional theory (DFT) based ab-initio approach. On adsorption of H 2 S, the variations in original metallic behaviour of ZGNR and semiconducting behaviour of AGNR has further been analysed by observing the conductance and bandgap variation as a function of H 2 S distance from GNR surface. The HOMO-LUMO profiles have also been analysed to understand the chemistry of GNRs and H 2 S molecule. Further, the current-voltage characteristics in presence of H 2 S near the nanoribbon surface, also shows the sensing of H 2 S, discussed in terms of that the current in both the nanoribbons increases due to H 2 S presence. The computed sensitivity confirms the zigzag GNR as better sensor than its armchair counterpart however, relatively with less recovery time than its zigzag counterpart. [ABSTRACT FROM AUTHOR]