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131.
132.
M Kay R Wyllie W Michener M Caulfield R Steffen 《Canadian Metallurgical Quarterly》1993,60(6):473-478
We report two young men with clinical and laboratory evidence of macroscopic ulcerative colitis, sclerosing cholangitis, and insulin-dependent diabetes mellitus. The first patient presented at age 15 with vomiting, abdominal pain, weight loss, and abnormal liver function test results. Liver biopsy and endoscopic retrograde cholangiopancreatography (ERCP) demonstrated sclerosing cholangitis. Colonoscopy with biopsy revealed ulcerative colitis which responded to sulfasalazine. Diabetes occurred at age 18 and insulin therapy was begun. The second patient was 19 at presentation with diarrhea, hematochezia, and weight loss. Proctosigmoidoscopy revealed ulcerative colitis, and sulfasalazine led to clinical remission. Three months later he developed diabetes requiring insulin therapy. At age 28, he developed elevated alkaline phosphatase, and ERCP revealed sclerosing cholangitis. At age 37 he expired from adenocarcinoma that metastasized to the liver. Literature review revealed only one possible case report of this association with microscopic asymptomatic ulcerative colitis in that patient. Statistical analysis suggests that this association is real rather than a chance occurrence. An autoimmune process may be involved and a specific histocompatibility locus antigen (HLA) type may exert a regulatory influence. 相似文献
133.
Christina Polasky Armin Steffen Kristin Loyal Christian Lange Karl-Ludwig Bruchhage Ralph Pries 《International journal of molecular sciences》2021,22(21)
Obstructive sleep apnea (OSA) is characterized by nocturnal breathing intermissions resulting in oxidative stress and eventually, a low-grade systemic inflammation. The study aimed to investigate the impact of positive airway pressure (PAP) therapy on the inflammatory milieu as measured by monocyte and T cell phenotypic alterations. Participants were assessed for their OSA severity before PAP therapy and about six months later, including patient-reported outcome and therapy usage by telemetry readout. The distributions of the CD14/CD16-characterized monocyte subsets as well as the CD4/CD8-characterized effector T cell subsets with regard to their PD-1 and PD-L1 expression were analyzed by flow cytometry from blood samples. Data of 25 patients revealed a significant reconstitution of the monocyte subset distribution and a decrease in PD-L1 expression on pan-monocytes and CD8+ T cells without an association to initial AHI and overweight. The PD-1 expression was still increased on T cell subsets, especially on CD4+ TH17/22 cells. We conclude that PAP therapy might have a rapid effect on the monocyte phenotype and overall PD-L1 expression levels. However, T cell immune alterations especially on TH17/22 cells persist longer, indicating an ongoing disturbance of the adaptive immune system. 相似文献
134.
135.
Climate policies for road transport revisited (II): Closing the policy gap with cap-and-trade 总被引:2,自引:0,他引:2
Current policies in the road transport sector fail to deliver consistent and efficient incentives for greenhouse gas abatement (see companion article by Creutzig et al., in press). Market-based instruments such as cap-and-trade systems close this policy gap and complement traditional policies that are required where specific market failures arise. Even in presence of strong existing non-market policies, cap-and-trade delivers additional abatement and efficiency by incentivizing demand side abatement options. This paper analyzes generic design options and economic impacts of including the European road transport sector into the EU ETS. Suitable points of regulation are up- and midstream in the fuel chain to ensure effectiveness (cover all emissions and avoid double-counting), efficiency (incentivize all abatement options) and low transaction costs. Based on year 2020 marginal abatement cost curves from different models and current EU climate policy objectives we show that in contrast to conventional wisdom, road transport inclusion would not change the EU ETS allowance price. Hence, industrial carbon leakage induced by adding road transport to the EU ETS may be less important than previously estimated. 相似文献
136.
TJ Walters PA Mason CJ Sherry C Steffen JH Merritt 《Canadian Metallurgical Quarterly》1995,66(6):562-567
A wide range assessment of the possible bioeffects of an acute exposure to high peak power ultra-wide band (UWB) electromagnetic radiation was performed in rats. The UWB-exposure consisted of 2 min of pulsed (frequency: 60 Hz, pulse width: 5-10 ns) UWB (bandwidth: 0.25-2.50 GHz) electromagnetic radiation. Rats were examined using one of the following: 1) a functional observational battery (FOB); 2) a swimming performance test; 3) a complete panel of blood chemistries; or 4) determination of the expression of the c-fos protein in immunohistologically-stained sections of the brain. No significant differences were found between UWB- or sham-exposed rats on any of the measured parameters. 相似文献
137.
We develop a model-checking algorithm for a logic that permits propositions to be defined using greatest and least fixed points of mutually recursive systems of equations. This logic is as expressive as the alternation-free fragment of the modal mu-calculus identified by Emerson and Lei, and it may therefore be used to encode a number of temporal logics and behavioral preorders. Our algorithm determines whether a process satisfies a formula in time proportional to the product of the sizes of the process and the formula; this improves on the best known algorithm for similar fixed-point logics. 相似文献
138.
Stefan Reis Steffen Nitter Rainer Friedrich 《Environmental Modelling & Software》2005,20(12):1524-1531
In this paper, crucial aspects of the implications and the complexity of interconnected multi-pollutant multi-effect assessments of both air pollution control strategies and the closely related reduction of greenhouse gas emissions will be discussed. The main aims of the work described here are to identify the core problems which occur when trying to apply current state-of-the-art methodology to conduct integrated assessments – in this context, cost-benefit assessment (CBA) as well as cost-effectiveness assessment (CEA) – using sophisticated computer models and propose solutions to the problems identified. The approaches described will display the integrated use of databases, efficient algorithms and already existing software tools and models in a unified model framework. The first part of the paper discusses the need for new developments in one particular field of Integrated Assessment Models (IAMs), which is the use of (typically) country-specific single pollutant abatement cost curves, which have been applied in a large number of modelling approaches with the aim to find cost-effective solutions for given air quality targets. However, research conducted to find such cost-effective solutions for the non-linear problem of tropospheric ozone abatement (dealing with two primary pollutants and their rather complex relationship to form tropospheric ozone, [see] [Friedrich, R., Reis, S. (Eds.), 2000. Tropospheric Ozone Abatement – Developing Efficient Strategies for the Reduction of Ozone Precursor Emissions in Europe. Springer Publishers] identified basic problems of cost curve based approaches even in this two-pollutant case. The approach discussed here promises to solve the key problems identified, making extensive use of databases in order to provide fast and high quality model input for CEA and CBA. In addition to that, the application of Genetic Algorithms will be discussed as a means to address extremely complex, vast solution spaces which are typical for the tasks IAMs are set to solve nowadays. As the application of the model in extensive assessment studies is currently under way, it is yet too early for a full evaluation of lessons learned. However, initial tests of performance and behaviour have shown robust and promising results. 相似文献
139.
Johannes Schemmel Steffen Hohmann Karlheinz Meier Felix Schürmann 《Analog Integrated Circuits and Signal Processing》2004,38(2-3):233-244
A hardware neural network is presented that combines digital signalling with analog computing. This allows a high amount of parallelism in the synapse operation while maintaining signal integrity and high transmission speed throughout the system. The presented mixed-mode implementation achieves a synapse density of 4 k per mm2 in 0.35 μm CMOS. The current-mode operation of the analog core combined with differential neuron inputs reaches an analog precision sufficient for 10 bit parity while running at a speed of 0.8 Teraconnections per second. 相似文献
140.
Applications of optical technologies like vision care, digital imaging or data communication play a decisive role in our daily life. Manipulation of light is mainly done using optical lenses. Beside mineral lenses, transparent plastic materials become more and more important. The optical and mechanical properties of lenses are crucially improved by high‐quality coatings. These includes primarily anti‐reflective coatings to enhance light transmission, hard coats to improve scratch resistance of the sensitive plastic substrates and finally clean coats to inhibit dusting of the lenses and to ease cleaning. In the following we present modern vacuum coating technologies for industrial refinement of optical substrates. The focal point is set to the coating of plastic eyeglass lenses using a revolutionary inline technology. On one hand the technology merges all coating steps in a fully automated system and enables on the other hand the flexible combination of different layer stacks necessary for RX‐production of ophthalmic lenses. This inline technology is available by the coating system OPTICUS. The design of the OPTICUS is described in the last chapter. 相似文献