20 research outputs found

    Isoelectronic Trap Like Luminescence Centers Of Ingan

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    AbstractThis paper describes the characteristics of the luminescence centers observed in the various photoluminescence (PL) and photoluminescence excitation (PLE) spectra of hexagonal InxGa1−xN microcrystals, synthesized by the nitridation of sulfide in the In concentration range of 2%&lt;x&lt;6%. The grown crystals showed macroscopic and microscopic inhomogeneity. A series of component bands expressed by Gaussian functions with discrete peak energies selected from the frequently observed peaks in the PL spectra and full width at half maximum obtained from the narrowest PL bands were fitted well to observed broad emission bands. As some of the peak energies of the component bands coincide with those of the bands that are attributed to the decay of excitons at the localized states caused by the In content fluctuation in the literature, we concluded the luminescence center for the component bands also originates from the fluctuation of the In contents. Although the In contents of the samples determined by the X ray diffraction method were compatible the gap energies from the PLE measurements were different. The PLE spectra showed that the Stokes shifts were large and the gap energies were irrelevant to the emission band peaks. The excitation bands for the emission bands in the range of 2.8 to 2.48 eV were located at 3.36, 3.26, and 3.21 eV. These results indicate that the states of the luminescence center are localized and the energy levels are discrete. To obtain the microscopic structure of the localized states in InxGa1−xN, we propose the isoelectronic atom cluster model comparable with Te clusters in ZnSeTe.</jats:p

    Localized luminescence centers of InGaN

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    Open-Source Software for Building-Integrated Photovoltaic Tiling for Novelty Architecture

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    Novelty architecture buildings can be tiled with conventional rectangular solar photovoltaic (PV) modules with both close-packed cells or partially transparent modules, vastly increasing renewable energy, reducing carbon emissions, and allowing for positive energy buildings. To enable this potential, in this study, for the first time, two open-source programs were developed and integrated to provide a foundation for designing and coating real-life novelty architecture buildings and objects with solar PV modules. First, a tiling algorithm was proposed and integrated into Blender that can generate solar PV modules on the face of any 3D model, and an augmented Python version of SAM was developed to simulate the performance of the resultant irregularly shaped PV systems. The integrated open-source software was used to analyze the energy performance of seven different novelty BIPVs located across the globe. The buildings&rsquo; energy performance was compared to conventional ground-based PV systems, and the results showed that the conventional arrays generate more energy per unit power than the BIPVs. The analysis reveals that the more complex the building model geometry, the less energy the building generates; however, the novelty BIPV power and energy densities far surpass conventional ground-based PV. The real estate savings observed were substantial, reaching 170% in one case where the BIPV reached 750 m in height. The BIPVs&rsquo; energy production is optimized by orienting the building via rotation and only needs to be carried out a single time for replication anywhere globally. The results show that the energy yield of the BIPV increases as the building becomes more detailed while the total power and energy decrease, indicating the need for the careful balancing of priorities in building design. Finally, the energy simulations demonstrate the potential for net-positive energy buildings and contribute to net-zero-emission cities. The findings indicate that BIPVs are not only appropriate for conventional residential houses and commercial buildings, but also for historical building replicas or monuments in the future. Further studies are needed to investigate the structural, electrical, and socio-economic aspects of novelty-architecture BIPVs

    Sepsis-Induced Coagulopathy and Japanese Association for Acute Medicine DIC in Coagulopathic Patients with Decreased Antithrombin and Treated by Antithrombin

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    Disseminated intravascular coagulation (DIC) in patients with sepsis represents a critical condition. Thus, a simple and rapid diagnosis is required. The purpose of this study was to compare the performances of a recently developed Sepsis-Induced Coagulopathy (SIC) with the Japanese Association for Acute Medicine (JAAM) DIC. Four hundred nine patients with sepsis having coagulopathy and antithrombin activity of less than 70% and treated with antithrombin were retrospectively analyzed, and the SIC and JAAM-DIC criteria on days 1 (before treatment), 2, 4, and 7 were compared. The prevalence of JAAM-DIC on day 1 was significantly higher than that of SIC (91.4% vs 81.8%, P = .003), but there were no differences on days 2, 4, and 7. The mortality rates in the SIC and JAAM-DIC groups were both 23.3%. The specificity to 28-day mortality on day 1 was higher in the SIC group (15.8% vs 9.2%, P = .013). There were no differences in sensitivity on days 1, 2, 4, and 7. Mortality was significantly different between SIC-positive and SIC-negative groups on days 2, 4, and 7 ( P &lt; .01, respectively), while significant differences were seen between JAAM-DIC-positive and JAAM-DIC-negative groups only on days 4 and 7 ( P &lt; .05, .01, respectively). In summary, the SIC characteristics were similar to the JAAM-DIC group, and the classifications were comparable in terms of mortality prediction. The SIC scoring system is simple, easy to use, and adaptable to the new sepsis definitions and offers an important approach to evaluating patients in emergency and critical care settings. </jats:p

    Abstract 1703: Nicotine-induced gemcitabine resistance is reversed by gamma-aminobutyric acid but enhanced by baclofen in pancreatic cancer xenografts and in pancreatic cancer cells <i>in vitro</i>

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    Abstract Pancreatic cancer is frequently resistant to cancer therapeutics. Smoking and alcoholism are risk factors and pancreatic cancer patients often undergo nicotine replacement therapy (NRT) and treatment for alcohol dependence. Based on our report that low dose nicotine within the range of NRT causes gemcitabine resistance in pancreatic cancer, our current study has tested the hypothesis that GABA or the selective GABA-B-R agonist baclofen used to treat alcohol dependence reverse nicotine-induced gemcitabine resistance in pancreatic cancer. Using pancreatic cancer cell lines BXPC-3 and PANC-1, our data show that GABA significantly reversed gemcitabine resistance induced by low dose nicotine in xenografts whereas baclofen did not. This effect of GABA was accompanied by decreases in cAMP, p-CREB, p-AKT, p-Src, p-ERK metalloproteinases-9 and -2 and EGR-1 and increases in cleaved caspase-3 in xenografts whereas baclofen had the opposite effects. In vitro exposure of cells to single doses or seven days of nicotine induced the protein expression of MMP-2, MMP-9 and EGR-1 and these responses were blocked by GABA. Baclofen downregulated the protein expression of GABA-B-Rs in xenograft tissues and in cells exposed to baclofen for seven days in vitro. This response was accompanied by inversed baclofen effects from inhibition of cAMP formation after single dose exposures to stimulation of cAMP formation in cells pretreated for seven days. These findings suggest GABA as a promising agent to overcome nicotine-induced gemcitabine resistance in pancreatic cancer whereas treatment of alcoholism by baclofen may increase gemcitabine resistance. Supported by grants RO1CA130888 and RO1CA042829 with the National Cancer Institute. Citation Format: Jheelam Banerjee, Hussein A. N Al-Wadei, Mohammed H. Al-Wadei, Koami Dagnon, Hildegard M. Schuller. Nicotine-induced gemcitabine resistance is reversed by gamma-aminobutyric acid but enhanced by baclofen in pancreatic cancer xenografts and in pancreatic cancer cells in vitro. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 1703. doi:10.1158/1538-7445.AM2014-1703</jats:p
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