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排序方式: 共有1774条查询结果,搜索用时 187 毫秒
91.
92.
Rafaelle Spear Ludovic Boytard Renaud Blervaque Maggy Chwastyniak David Hot Jonathan Vanhoutte Bart Staels Yves Lemoine Nicolas Lamblin Fran?ois-René Pruvot Stephan Haulon Philippe Amouyel Florence Pinet 《International journal of molecular sciences》2015,16(5):11276-11293
Abdominal aortic aneurysm (AAA) is an inflammatory disease associated with marked changes in the cellular composition of the aortic wall. This study aims to identify microRNA (miRNA) expression in aneurysmal inflammatory cells isolated by laser microdissection from human tissue samples. The distribution of inflammatory cells (neutrophils, B and T lymphocytes, mast cells) was evaluated in human AAA biopsies. We observed in half of the samples that adventitial tertiary lymphoid organs (ATLOs) with a thickness from 0.5 to 2 mm were located exclusively in the adventitia. Out of the 850 miRNA that were screened by microarray in isolated ATLOs (n = 2), 164 miRNAs were detected in ATLOs. The three miRNAs (miR-15a-3p, miR-30a-5p and miR-489-3p) with the highest expression levels were chosen and their expression quantified by RT-PCR in isolated ATLOs (n = 4), M1 (n = 2) and M2 macrophages (n = 2) and entire aneurysmal biopsies (n = 3). Except for the miR-30a-5p, a similar modulation was found in ATLOs and the two subtypes of macrophages. The modulated miRNAs were then evaluated in the plasma of AAA patients for their potential as AAA biomarkers. Our data emphasize the potential of miR-15a-3p and miR-30a-5p as biomarkers of AAA but also as triggers of ATLO evolution. Further investigations will be required to evaluate their targets in order to better understand AAA pathophysiology. 相似文献
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Aggregates were formed by heating mixtures of whey protein isolate (WPI) and pure κ-casein or sodium caseinate at pH 7 and 0.1 M NaCl. The aggregates were characterized by static and dynamic light scattering and size exclusion chromatography. After extensive heat-treatment at 80 °C for 24 h, almost all whey proteins and κ-casein formed mixed aggregates, but a large proportion of the sodium caseinate did not aggregate. At a given WPI concentration the size of the aggregates decreased with increasing κ-casein or sodium caseinate concentration, but the overall self-similar structure of the aggregates was the same. The presence of κ-casein or caseinate therefore inhibited growth of the heat-induced whey protein aggregates. The results were discussed relative to the reported chaperone-like activity of casein molecules towards heat aggregation of globular proteins. 相似文献
95.
A systematic comparison of PCA‐based Statistical Process Monitoring methods for high‐dimensional,time‐dependent Processes
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Tiago Rato Marco Reis Eric Schmitt Mia Hubert Bart De Ketelaere 《American Institute of Chemical Engineers》2016,62(5):1478-1493
High‐dimensional and time‐dependent data pose significant challenges to Statistical Process Monitoring. Most of the high‐dimensional methodologies to cope with these challenges rely on some form of Principal Component Analysis (PCA) model, usually classified as nonadaptive and adaptive. Nonadaptive methods include the static PCA approach and Dynamic Principal Component Analysis (DPCA) for data with autocorrelation. Methods, such as DPCA with Decorrelated Residuals, extend DPCA to further reduce the effects of autocorrelation and cross‐correlation on the monitoring statistics. Recursive Principal Component Analysis and Moving Window Principal Component Analysis, developed for nonstationary data, are adaptive. These fundamental methods will be systematically compared on high‐dimensional, time‐dependent processes (including the Tennessee Eastman benchmark process) to provide practitioners with guidelines for appropriate monitoring strategies and a sense of how they can be expected to perform. The selection of parameter values for the different methods is also discussed. Finally, the relevant challenges of modeling time‐dependent data are discussed, and areas of possible further research are highlighted. © 2016 American Institute of Chemical Engineers AIChE J, 62: 1478–1493, 2016 相似文献
96.
Toon Verstraelen Bartłomiej M. Szyja David Lesthaeghe Reinout Declerck Veronique Van Speybroeck Michel Waroquier Antonius P. J. Jansen Alexander Aerts Lana R. A. Follens Johan A. Martens Christine E. A. Kirschhock Rutger A. van Santen 《Topics in Catalysis》2009,52(9):1261-1271
Zeolite synthesis is driven by structure-directing agents, such as tetrapropyl ammonium ions (TPA+) for Silicalite-1 and ZSM-5. However, the guiding role of these organic templates in the complex assembly to highly ordered
frameworks remains unclear, limiting the prospects for advanced material synthesis. In this work, both static ab initio and
dynamic classical modeling techniques are employed to provide insight into the interactions between TPA+ and Silicalite-1 precursors. We find that as soon as the typical straight 10-ring channel of Silicalite-1 or ZSM-5 is formed
from smaller oligomers, the TPA+ template is partially squeezed out of the resulting cavity. Partial retention of the template in the cavity is, however,
indispensable to prevent collapse of the channel and subsequent hydrolysis.
相似文献
Rutger A. van Santen (Corresponding author)Email: |
97.
M. Mitri D. Nicolai O. Neubauer H.T. Lambertz I. Schmidt A. Khilchenko B. Schweer U. Maier U. Samm 《Fusion Engineering and Design》2009,84(7-11):1329-1332
The tokamak TEXTOR at the Research Centre in Jülich is in operation since more than 25 years. The various control systems at the start, in 1982, were based on analogue techniques, a standard at the time, and were later partly replaced by specially developed digital systems. These systems proved their robustness over the years. As a replacement for the old system, off-the-shelf products were used to ensure continuity, reliability and to reduce the development cost. To provide advanced control scenarios, the new system allows the implementation of more sophisticated algorithms for magnetic and kinetic control. The LabVIEW Real-Time (RT) modules and real-time hardware from National Instruments satisfy these requirements to a large extent. The new system has already been successfully commissioned at TEXTOR and is used to calculate in real-time the plasma density profile (10 ms), the Shafranov shift (10 ms), the plasma vertical and horizontal position (20 s) and to control the plasma shape (1 ms). TEXTOR has circular plasmas and has an iron core. Its central part is operated in saturation. During the saturation phase, stray fields change the plasma shape from nearly circular to slightly triangular. By using a shape-control coil set, we can control and adjust the plasma form. The new real-time system is presented as well as the implemented control applications. 相似文献
98.
Wouter M.J. Achten Joana Almeida Vincent Fobelets Evelien Bolle Erik Mathijs Virendra P. Singh Dina N. Tewari Louis V. Verchot Bart Muys 《Applied Energy》2010
Since 2003 India has been actively promoting the cultivation of Jatropha on unproductive and degraded lands (wastelands) for the production of biodiesel suitable as transportation fuel. In this paper the life cycle energy balance, global warming potential, acidification potential, eutrophication potential and land use impact on ecosystem quality is evaluated for a small scale, low-input Jatropha biodiesel system established on wasteland in rural India. In addition to the life cycle assessment of the case at hand, the environmental performance of the same system expanded with a biogas installation digesting seed cake was quantified. The environmental impacts were compared to the life cycle impacts of a fossil fuel reference system delivering the same amount of products and functions as the Jatropha biodiesel system under research. The results show that the production and use of Jatropha biodiesel triggers an 82% decrease in non-renewable energy requirement (Net Energy Ratio, NER = 1.85) and a 55% reduction in global warming potential (GWP) compared to the reference fossil-fuel based system. However, there is an increase in acidification (49%) and eutrophication (430%) from the Jatropha system relative to the reference case. Although adding biogas production to the system boosts the energy efficiency of the system (NER = 3.40), the GWP reduction would not increase (51%) due to additional CH4 emissions. For the land use impact, Jatropha improved the structural ecosystem quality when planted on wasteland, but reduced the functional ecosystem quality. Fertilizer application (mainly N) is an important contributor to most negative impact categories. Optimizing fertilization, agronomic practices and genetics are the major system improvement options. 相似文献
99.
100.
R.T. EiswirthH.-J. Bart T. AtmakidisE.Y. Kenig 《Chemical Engineering and Processing: Process Intensification》2011,50(7):718-727
A toluene droplet rising in a continuous aqueous phase is studied both experimentally and numerically. The experiments have been performed in a small scale, high-speed measuring unit with a high magnification device to image the process in all details. Numerical simulations are performed with the aid of the level set method implemented in the commercial CFD tool COMSOL Multiphysics 3.3a by COMSOL AB. A new technique for quantitative comparison of experimental and numerical results with respect to the droplet shape is presented. Both terminal velocity and droplet shape in experiments and simulations are found to be in excellent agreement. Based on the experimental and numerical data obtained, an improvement of an existing terminal velocity correlation is suggested. The adjusted correlation can be used for the design and optimisation of liquid-liquid extraction units. 相似文献