2,201 research outputs found

    Calibration of TCCON column-averaged CO2: the first aircraft campaign over European TCCON sites

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    The Total Carbon Column Observing Network (TCCON) is a ground-based network of Fourier Transform Spectrometer (FTS) sites around the globe, where the column abundances of CO2, CH4, N2O, CO and O2 are measured. CO2 is constrained with a precision better than 0.25% (1-σ). To achieve a similarly high accuracy, calibration to World Meteorological Organization (WMO) standards is required. This paper introduces the first aircraft calibration campaign of five European TCCON sites and a mobile FTS instrument. A series of WMO standards in-situ profiles were obtained over European TCCON sites via aircraft and compared with retrievals of CO2 column amounts from the TCCON instruments. The results of the campaign show that the FTS measurements are consistently biased 1.1% ± 0.2% low with respect to WMO standards, in agreement with previous TCCON calibration campaigns. The standard a priori profile for the TCCON FTS retrievals is shown to not add a bias. The same calibration factor is generated using aircraft profiles as a priori and with the TCCON standard a priori. With a calibration to WMO standards, the highly precise TCCON CO2 measurements of total column concentrations provide a suitable database for the calibration and validation of nadir-viewing satellite

    Перевод паровой котельной на водогрейный режим г. Кедровый Томской области

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    Выпускная квалификационная работа 172 страницы, 17 табл., 8 рисунков, 21 источник литературы, 8 листов графического материала. КОТЕЛЬНАЯ ПРОИЗВОДСТВЕННО - ОТОПИТЕЛЬНАЯ, КОТЕЛ ПАРОВОЙ, ВОДОГРЕЙНЫЙ РЕЖИМ, ТЕПЛОВОЙ, ГИДРАВЛИЧЕСКИЙ, АЭРОДИНАМИЧЕСКИЙ РАСЧЕТ, ЭКОНОМИЧЕСКИЙ ЭФФЕКТ. Целью работы является перевод котла ДКВр-10-13 с парового режима работы в водогрейный.Final qualifying work of 172 pages, 17 tab., 8 figures, 21 source of literature, 8 sheets of graphic material. INDUSTRIAL BOILER - Heating, steam boiler, hot-water boilers, thermal, hydraulic, aerodynamic calculations, the economic effect. The aim is to transfer the boiler DKVr-10-13 with steam mode to hot water

    Decreased expression of breast cancer resistance protein in the duodenum in patients with obstructive cholestasis

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    Background/Aims: The expression of transporters involved in bile acid homeostasis is differentially regulated during obstructive cholestasis. Since the drug efflux transporter breast cancer resistance protein (BCRP) is known to transport bile acids, we investigated whether duodenal BCRP expression could be altered during cholestasis. Methods: Using real-time RT-PCR analysis we determined mRNA expression levels in duodenal tissue of 19 cholestatic patients. Expression levels were compared to 14 healthy subjects. BCRP protein staining was determined in biopsies of 6 cholestatic and 6 healthy subjects by immunohistochemistry. Results: We found that in patients with obstructive cholestasis mean duodenal BCRP mRNA levels were significantly reduced to 53% and mean protein staining was reduced to 57%. Conclusions: BCRP, a transporter for bile acids and numerous drugs, appears to be down-regulated in the human duodenum during cholestasis. The clinical impact of these results has to be investigated in further studies. Copyright (c) 2006 S. Karger AG, Basel

    Организация работ по охране труда и оценка рисков работников нефтегазодобывающего предприятия

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    Несмотря на усовершенствование технологических процессов и вводимые меры по обеспечению безопасности труда, на предприятиях существует тенденция к снижению себестоимости продукции. В связи с этим увеличивается вероятность возникновения производственных рисков на промышленных предприятиях, которые рассмотрены в данной работе на примере нефтегазодобывающего управления "Федоровскнефть".Despite the improvement of technological processes and the introduction of measures to ensure labor safety, there is a tendency at enterprises to reduce the cost of production. In this connection, the probability of occurrence of industrial risks in industrial enterprises is increased, which are considered in this work by the example of oil and gas production department "Fedorovskneft"

    In Vivo Imaging of Stepwise Vessel Occlusion in Cerebral Photothrombosis of Mice by 19F MRI

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    Background 19^{19}F magnetic resonance imaging (MRI) was recently introduced as a promising technique for in vivo cell tracking. In the present study we compared 19^{19}F MRI with iron-enhanced MRI in mice with photothrombosis (PT) at 7 Tesla. PT represents a model of focal cerebral ischemia exhibiting acute vessel occlusion and delayed neuroinflammation. Methods/Principal Findings Perfluorocarbons (PFC) or superparamagnetic iron oxide particles (SPIO) were injected intravenously at different time points after photothrombotic infarction. While administration of PFC directly after PT induction led to a strong 19^{19}F signal throughout the entire lesion, two hours delayed application resulted in a rim-like 19^{19}F signal at the outer edge of the lesion. These findings closely resembled the distribution of signal loss on T2-weighted MRI seen after SPIO injection reflecting intravascular accumulation of iron particles trapped in vessel thrombi as confirmed histologically. By sequential administration of two chemically shifted PFC compounds 0 and 2 hours after illumination the different spatial distribution of the 19^{19}F markers (infarct core/rim) could be visualized in the same animal. When PFC were applied at day 6 the fluorine marker was only detected after long acquisition times ex vivo. SPIO-enhanced MRI showed slight signal loss in vivo which was much more prominent ex vivo indicative for neuroinflammation at this late lesion stage. Conclusion Our study shows that vessel occlusion can be followed in vivo by 19^{19}F and SPIO-enhanced high-field MRI while in vivo imaging of neuroinflammation remains challenging. The timing of contrast agent application was the major determinant of the underlying processes depicted by both imaging techniques. Importantly, sequential application of different PFC compounds allowed depiction of ongoing vessel occlusion from the core to the margin of the ischemic lesions in a single MRI measurement

    How to perform Contrast-Enhanced Ultrasound (CEUS)

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    "How to perform contrast-enhanced ultrasound (CEUS)" provides general advice on the use of ultrasound contrast agents (UCAs) for clinical decision-making and reviews technical parameters for optimal CEUS performance. CEUS techniques vary between centers, therefore, experts from EFSUMB, WFUMB and from the CEUS LI-RADS working group created a discussion forum to standardize the CEUS examination technique according to published evidence and best personal experience. The goal is to standardise the use and administration of UCAs to facilitate correct diagnoses and ultimately to improve the management and outcomes of patients

    Semaphorin 6A Improves Functional Recovery in Conjunction with Motor Training after Cerebral Ischemia

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    Background: We have previously identified Semaphorin 6a (Sema6A) as an upregulated gene product in a gene expression screen in cortical ischemia [1]. Semaphorin 6a was regulated during the recovery phase following ischemia in the cortex. Semaphorin 6a is a member of the superfamily of semaphorins involved in axon guidance and other functions. We hypothesized that the upregulation indicates a crucial role of this molecule in post-stroke rewiring of the brain. Here we have tested this hypothesis by overexpressing semaphorin 6a in the cortex by microinjection of a modified AAV2-virus. A circumscribed cortical infarct was induced, and the recovery of rats monitored for up to 4 weeks using a well-established test battery (accelerated rotarod training paradigm, cylinder test, adhesive tape removal). We observed a significant improvement in post-ischemic recovery of animals injected with the semaphorin 6a virus versus animals treated with a control virus. We conclude that semaphorin 6a overexpressed in the cortex enhances recovery after cerebral ischemia
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