310 research outputs found

    Flood Frequency Estimation by Neyman-Scott Rectangular Pulse Rainfall Model and TOPMODEL

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    A spatial-temporal Neyman-Scott Rectangular Pulse (NSRP) stochastic rainfall model is developed for seasonal-continuous simulation to project annual discharge probabilities from a relatively small watershed, the 1395 km2 Upper Iowa River watershed upstream from Decorah, Iowa. NSRP rainfall data is used as rainfall input to TOPMODEL, a conceptual, semidistributed rainfall runoff model, to calculate river discharge at a site common to the United States Geological Survey (USGS) gauging station in Decorah, Iowa. Annual peak flows based on simulated rainfall are used to fit a log-Pearson type III distribution to project 1 %-, 0.2%-, and 0.1 %-annual discharges. These results are compared to projections for the same frequency flows based on observed annual peak flow data measured at the USGS gauge site in Decorah. The NSRP model parameters are modified to reflect changes in environmental storm parameters (e.g. rainfall intensity and storm frequency) due to a warming atmosphere to study the sensitivity of annual peak flows due to climate variations

    Struktur innerer Grenzflächen von Halbleiter-Heterostrukturen und ihre Auswirkung auf optische Eigenschaften

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    A statistical, spatial, and hydrologic comparison of gauge-based and MPE-based rainfall measurements

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    Gauge-based and multi-sensor precipitation estimation (MPE) data are compared on hourly, daily, monthly and event time scales at site locations over a 12-year period. Gauge data is collected at 16 sites within a 950 km2 portion of the Upper Iowa River in northeast Iowa. Average relative MPE bias is positive for all but the event time scale, and has a magnitude of less than 0.10 for all scales. Gauge and MPE average correlation coefficients range from 0.73 on the hourly scale to 0.92 on the event and monthly scales. The MPE relative bias standard deviation decreases from 1.70 mm on the hourly scale to 0.27 mm on the monthly scale. Decomposition of hourly bias reveals that the false positive portion is the most significant component. Seventy percent of MPE accumulation have a relative bias of 0.5 or less when hourly accumulations are 7 mm or greater. Pearson product-moment coefficient analysis reveals strong similarities in spatial correlations as a function of site separation. Rainfall time series for the basin are constructed from the two data sources and used as input to a Blocked Topmodel rainfall runoff scheme to provide another means of comparison on a basin-wide spatial scale. Five goodness-of-fit measures are used for quantifying the viability of simulated flows. No statistically significant difference in annual means using the difference sources is found for any of the measures

    Synchronous primary intrapulmonary and mediastinal thymoma-A case report

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    We report an extremely rare case of Synchronous primary intrapulmonary and mediastinal thymoma in a Chinese patient. We describe the histological and radiological findings, which support the possibility of multicentric thymoma. Resection of the mass in the left anterior superior mediastinum and upper lobectomy of right lung were performed, with lymph Nodes clearance, superior vena cava, left and right brachiocephalic veins resection, reconstruction of left brachiocephalic vein to right auricle and reconstruction of right brachiocephalic vein to superior vena cava

    Barotraumatic Perforation of Pharyngoesophagus by Explosion of a Bottle into the Mouth

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    Pharyngoesophageal perforation from an exploding bottle is an extremely rare injury. To date, twenty-four cases have been documented in English literature. In this study, we reported two additional cases of pharyngoesophageal perforation by a bottle exploding in the mouth. Explosion of the bottle occurred when the patients removed the cap of a home-made wine bottle with their teeth, which resulted in pharyngoesophageal perforation. The patients were managed by conservative treatment and operative repair, respectively. Both patients had an uneventful recovery. Possible mechanisms and preventive measures are discussed in this study, along with a review of the literature

    Inhibition of mitochondrial respiration prevents BRAF-mutant melanoma brain metastasis

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    Melanoma patients carry a high risk of developing brain metastases, and improvements in survival are still measured in weeks or months. Durable disease control within the brain is impeded by poor drug penetration across the blood-brain barrier, as well as intrinsic and acquired drug resistance. Augmented mitochondrial respiration is a key resistance mechanism in BRAF-mutant melanomas but, as we show in this study, this dependence on mitochondrial respiration may also be exploited therapeutically. We first used high-throughput pharmacogenomic profiling to identify potentially repurposable compounds against BRAF-mutant melanoma brain metastases. One of the compounds identified was β-sitosterol, a well-tolerated and brain-penetrable phytosterol. Here we show that β-sitosterol attenuates melanoma cell growth in vitro and also inhibits brain metastasis formation in vivo. Functional analyses indicated that the therapeutic potential of β-sitosterol was linked to mitochondrial interference. Mechanistically, β-sitosterol effectively reduced mitochondrial respiratory capacity, mediated by an inhibition of mitochondrial complex I. The net result of this action was increased oxidative stress that led to apoptosis. This effect was only seen in tumor cells, and not in normal cells. Large-scale analyses of human melanoma brain metastases indicated a significant role of mitochondrial complex I compared to brain metastases from other cancers. Finally, we observed completely abrogated BRAF inhibitor resistance when vemurafenib was combined with either β-sitosterol or a functional knockdown of mitochondrial complex I. In conclusion, based on its favorable tolerability, excellent brain bioavailability, and capacity to inhibit mitochondrial respiration, β-sitosterol represents a promising adjuvant to BRAF inhibitor therapy in patients with, or at risk for, melanoma brain metastases.publishedVersio
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