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In a previous study, the authors investigated that abnormal Vth behaviour could occur due to polyimide charging when a voltage was applied to the gate in thin film transistors fabricated on polyimide substrates. The authors propose a barrier structure that could prevent this charging effect when fabricating flexible thin film transistors on polyimide substrates. The barrier layer was changed to an SiOCH/SiO2 double layer to reduce the influence of fluorine ions generated in PI by negative bias temperature stress. To confirm the effect of the SiOCH layer, Al/PI/SiO2/Al, Al/PI/SiOCH/SiO2/Al metal‐insulator‐metal capacitors were fabricated and electrical properties were measured. When bias stress was applied, changes in current and capacitance were observed only in the device with a single SiO2 barrier layer. In addition, it was confirmed through secondary ion mass spectrometry measurements that the Si–CH3 bonds in the SiOCH layer were replaced with Si–F bonds by the fluorine ions originating from PI. It was also verified that the abnormal behaviour of Vth did not occur after negative bias temperature stress of the thin film transistor fabricated using an SiOCH/SiO2 double layer.

This study investigated evolution of the microstructure of oxide dispersion strengthened Alloy 617 with annealing temperature. A mixture of prealloyed Alloy 617 and Y2O3 powders was mechanically alloyed and consolidated by hot-extrusion at 1100 °C. Hot extrusion developed a submicron-sized grain structure with M23C6 carbides and finely dispersed Al2O3 and Y2Ti2O7 oxides. The fine-grained structure was stable during subsequent annealing at temperatures up to 1250 °C. Further increase of annealing temperature to 1300 °C resulted in a significantly coarsened grain structure, which was coincident with the abrupt coarsening of oxides. M23C6 carbides in the as-extruded conditions were transformed to M7C3 carbides with complex shapes when annealed at 1200 °C, and their shapes changed to very coarse hexagonal prisms at 1250 °C, which was followed by the formation of eutectic M2C carbides at grain boundaries at 1300 °C. Tensile tests of the as-extruded ODS Alloy 617 showed that the yield strength decreased steeply at a transition temperature of around 600 °C, which can be attributed to diffusional creep along the grain boundaries.

Necroptosis has been found to be involved in the pathogenesis of some lung diseases, but its role in hyperoxic acute lung injury (HALI) is still unclear. This study aimed to investigate contribution of necroptosis to the pathogenesis of HALI induced by hyperbaric hyperoxia exposure in a rat model. Rats were divided into control group, HALI group, Nec-1 (necroptosis inhibitor) group and edaravone group. Rats were exposed to pure oxygen at 250 kPa for 6 h to induce HALI. At 30 min before hyperoxia exposure, rats were intraperitoneally injected with Nec-1 or edaravone, and sacrificed at 24 h after hyperoxia exposure. Lung injury was evaluated by histology, lung water to dry ratio (W/D) and bronchoalveolar lavage fluid (BALF) biochemistry; the serum and plasma oxidative stress, expression of RIP1, RIP3 and MLKL, and interaction between RIP1 and RIP3 were determined. Results showed hyperoxia exposure significantly caused damage to lung and increased necroptotic cells and the expression of RIP1, RIP3 and MLKL. Edaravone pre-treatment not only inhibited the oxidative stress in HALI, but also reduced necroptotic cells, decreased the expression of RIP1, RIP3 and MLKL and improved lung pathology. Nec-1 pretreatment inhibited necroptosis and improved lung pathology, but had little influence on oxidative stress. This study suggests hyperoxia exposure induces oxidative stress may activate necroptosis, involving in the pathology of HALI, and strategies targeting necroptosis may become promising treatments for HALI.

Multiscale microstructure refinement of a 12Cr-ODS steel by equal channel angular extrusion (ECAE) was investigated by numerous microscopy techniques. The as-HIPped material showed a bimodal microstructure. Three types of second phase particles, including Y2O3, (Cr, Fe)23C6 and Cr oxide, were observed. After ECAE, the large matrix grains and Cr rich particles were effectively refined, and yttrium oxide nanoparticles surrounding ultrafine grain boundaries were redistributed. Geometry change of nanoscale yttrium oxide particles was also observed. An increased hardening by ∼35% was related to ECAE induced refinement of microstructures.

This paper present a design for X/Ku dual-band reflectarray antennas with single layer which has two independent radiation patterns for X and Ku bands. In the design, a novel dual resonance structure has been used as the unit cell for both X and Ku band to achieve dual-band performance with a new approach. A 10×10 center-fed reflectarray operating at 9 GHz and 13.5 GHz with scattering angles of 12° and -30° respectively, is designed and the simulated results are presented to validate the approach.

An experimental modal analysis is the process to identify structure's dynamic characteristics. For investigating vibrational characteristics of cylindrical shell with multiple supports, modal testing is performed using impact exciting method. The frequency response function(FRF) measurements are also made on the experimental model within the frequency range from 0 to 4kHz. Modal parameters are identified from resonant peaks in the FRF’s and animated deformation patterns associated with each of the resonances are shown on a computer screen. The experimental results are compared with analytical and FEA results.

Taguchi et al. first utilized AlN and MnS as grain growth inhibitors at the primary recrystallization stage and a nitrogen contained atmosphere at the secondary recrystallization stage to produce high quality grain oriented silicon steels with sharp {l_brace}110{r_brace} texture. Recently, further strengthening of the inhibition was realized by nitriding the final gauge steel sheet prior to the secondary recrystallization process. Though the beneficial effect of the nitrogen has been confirmed, there has not been sufficient understanding how the presence of the element changes the precipitate size and distribution. The authors investigated the size and distribution of AlN precipitates in 3% silicon steels under the influence of nitrogen in the matrix or annealing atmosphere. Final gauge steel sheets of 0.10 mm thickness were nitrided to have various nitrogen content in the matrix ([N]). They were, then, annealed under two different nitrogen partial pressures (100%H{sub 2}, 75%N{sub 2} + 25%H{sub 2}). Samples were taken prior to and at certain intervals during the annealing. Precipitates in the samples were inspected by analyzing the extraction replica images taken by transmission electron microscopy (TEM).

A new form of MOS transistor called L-type MOS transistor is proposed for high punchthrough voltage and scaled-down DRAM cells. Characteristics such as threshold voltage, subthreshold and back-bias effects are analytically derived and suppression of punchthrough is investigated using device simulation. The threshold voltage and substrate-bias sensitivity are larger than those of the planar MOS transistor. As the radius of curvature increases, these become close to those of the planar MOS. If the radius of curvature is above 0.3 μm, the subthreshold swing is only within 10% larger than that of the planar MOS. 2-Dimensional simulation results show that the L-type MOS transistor has a better punchthrough characteristic than the planar MOS transistor with the same substrate doping. The L-type MOS can be used in some specific ICs such as DRAM cells.

Background Contralateral acupuncture (CAT) involves inserting needles in the meridian on the side opposite the disease location and is often used in post-stroke rehabilitation. The aim of this systematic review is to summarize and critically evaluate the evidence for and against the effectiveness of CAT for post-stroke rehabilitation as compared to ipsilateral acupuncture (IAT). Methods Seventeen databases were searched from their inceptions through June 2010. Prospective clinical trials were included if CAT was tested as the sole treatment or as an adjunct to other treatments for post-stroke rehabilitation and compared to IAT. Results Eight randomized clinical trials (RCTs) met our inclusion criteria. Four of them reported favorable effects of CAT compared to IAT for at least one outcome. A meta-analysis showed superior effects of CAT compared to IAT on recovery rate (n = 361; risk ratio (RR), 1.12; 95 % confidence intervals (CIs), 1.04 to 1.22, p = 0.005). Subgroup analysis also showed favorable effects of using CAT on patients with cerebral infarction (n = 261; RR, 1.15; 95 % CIs, 1.04 to 1.27, p = 0.006). Further analysis including patients with cerebral infarction and intracranial hemorrhage, however, failed to show these advantages (n = 100; RR, 1.11; 95 % CIs, 0.85 to 1.46, p = 0.43). Conclusion The results of our systematic review and meta-analysis suggest that there is limited evidence for CAT being superior to IAT in the treatment of cerebral infarction. The total number of RCTs included in our analysis was low, however, and the RCTs included had a high risk of bias. Future RCTs appear to be warranted.

A method and a novel circuitry for intra- and inter-chip temperature measurement in a system in a package (SiP) module is presented. The proposed built-in self-test (BiST) system for the SiP module features a newly proposed digital frequency analyser (DFA) that can be used to efficiently discern clock period differences of up to 1 ns. The full digital interface of the DFA enables power and area efficient temperature measurements in an SiP.

In the present study, theoretical development proposed in previous work carried out in extrusion of clover sections in relation to a generalized die design method is presented in the extended scope for three-dimensional extrusion of trocoidal gear sections from round billets with experimental verification. Computations are carried out for clover and trocoidal gear sections. The CAD/CAM of the suggested dies is introduced for the experiments. Experiments are carried out for a clover section and a trocoidal gear section with eight teeth. Al 2024 aluminum billets were used as the working material. Half-cut specimens are used for flow visualization of the extrusion process. The theoretical predictions are in good agreement with the experimental results in extrusion load and metal flow.

13C NMR of isotopically enriched metabolites has been used to study the metabolism of Microbacterium ammoniaphilum, a bacterium which excretes large quantities of L-glutamic acid into the medium. Biosynthesis from 90% [1-13C]glucose results in relatively high specificity of the label, with [2,4-13C2]glutamate as the major product. The predominant biosynthetic pathway for synthesis of glutamate from glucose was determined to be the Embden Meyerhof glycolytic pathway followed by P-enolpyruvate carboxylase and the first third of the Krebs cycle. Different metabolic pathways are associated with different correlations in the enrichment of the carbons, reflected in the spectrum as different 13C-13C scalar multiplet intensities. Hence, intensity and 13C-13C multiplet analysis allows quantitation of the pathways involved. Although blockage of the Krebs cycle at the alpha-ketoglutarate dehydrogenase step is the basis for the accumulation of glutamate, significant Krebs cycle activity was found in glucose grown cells, and extensive Krebs cycle activity in cells metabolizing [1-13C]acetate. In addition to the observation of the expected metabolites, the disaccharide alpha, alpha-trehalose and alpha, beta-glucosylamine were identified from the 13C NMR spectra.