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11.
A linear-quadratic differential game in which the system state is affected by disturbance and both players have access to different measurements is solved. The problem is first converted to an optimization problem in infinite-dimensional state space and then solved using standard techniques. For convenience, L
2-white noise instead of Wiener process setup is used. 相似文献
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Selective Exo‐Enzymatic Labeling of N‐Glycans on the Surface of Living Cells by Recombinant ST6Gal I
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Huiqing Li Dr. Kai‐For Mo Dr. Qun Wang Dr. C. Kendall Stover Dr. Antonio DiGiandomenico Prof. Geert‐Jan Boons 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(51):17425-17431
Pseudomonas aeruginosa is an opportunistic Gram‐negative bacterium that can cause life‐threatening infections in critically ill and cystic fibrosis patients. The Psl exopolysaccharide of P. aeruginosa offers an attractive serotype‐independent antigen for the development of immunotherapies. Here, the first chemical synthesis of a panel of oligosaccharides derived from the exopolysaccharide of P. aeruginosa by a synthetic strategy that efficiently deals with the stereoselective installation of several β‐mannosides and the formation of a mannoside that is extended by saccharide moieties at C‐1, C‐2, and C‐3 in a crowded 1,2,3‐cis configuration is described. The approach was employed to prepare tetra‐, penta‐, and hexa‐ and decasaccharide part structures. The compounds were employed to define the epitope requirements of several functionally active monoclonal antibodies (mAbs) that can bind three distinct epitopes of Psl (class I, II, and III). The class II mAb reacted potently with each oligosaccharide indicating its epitope resides within the tetrasaccharide and does not require the branched mannoside of Psl. The class III antibody did not bind the tetra‐ or pentasaccharide; however, it did react potently with the hexasaccharide and weakly with the decasaccharide, suggesting a terminal glucoside is required for optimal binding. Unexpectedly, the class I mAb did not bind any of the oligosaccharides indicating that Psl contains a yet to be elucidated sub‐stoichiometric isoform. This study demonstrates that functional activity of a mAb does not only depend on the avidity of binding but also on the location of an epitope within a bacterial polysaccharide. The results also provide a strong impetus to analyze further the structure of Psl to identify the class I epitope, that is expected to provide an attractive target for the development of a synthetic vaccine for P. aeruginosa. 相似文献
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Barbara M. Liszka Aufried T. M. Lenferink Geert‐Jan Witkamp Cees Otto 《Journal of Raman spectroscopy : JRS》2015,46(12):1230-1234
The sensitivity of far‐field Raman micro‐spectroscopy was investigated to determine quantitatively the actual thickness of organic thin films. It is shown that the thickness of organic films can be quantitatively determined down to 3 nm with an error margin of 20% and down to 1.5 nm with an error margin of 100%. Raman imaging of thin‐film surfaces with a far‐field optical microscope establishes the distribution of a polymer with a lateral resolution of ~400 nm and the homogeneity of the film. Raman images are presented for spin‐coated thin films of polysulfone (PSU) with average thicknesses between 3 and 50 nm. In films with an average thickness of 43 nm, the variation in thickness was around 5% for PSU. In films with an average thickness of 3 nm for PSU, the detected thickness variation was 100%. Raman imaging was performed in minutes for a surface area of 900 µm2. The results illustrate the ability of far‐field Raman microscopy as a sensitive method to quantitatively determine the thickness of thin films down to the nanometer range. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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Hanna Talacua Serge H. M. Sntjens Shraddha H. Thakkar Aurelie M. A. Brizard Lex A. van Herwerden Aryan Vink Geert C. van Almen Patricia Y. W. Dankers Carlijn V. C. Bouten Ricardo P. J. Budde Henk M. Janssen Jolanda Kluin 《Macromolecular bioscience》2020,20(7)
For in situ tissue engineering (TE) applications it is important that implant degradation proceeds in concord with neo‐tissue formation to avoid graft failure. It will therefore be valuable to have an imaging contrast agent (CA) available that can report on the degrading implant. For this purpose, a biodegradable radiopaque biomaterial is presented, modularly composed of a bisurea chain‐extended polycaprolactone (PCL2000‐U4U) elastomer and a novel iodinated bisurea‐modified CA additive (I‐U4U). Supramolecular hydrogen bonding interactions between the components ensure their intimate mixing. Porous implant TE‐grafts are prepared by simply electrospinning a solution containing PCL2000‐U4U and I‐U4U. Rats receive an aortic interposition graft, either composed of only PCL2000‐U4U (control) or of PCL2000‐U4U and I‐U4U (test). The grafts are explanted for analysis at three time points over a 1‐month period. Computed tomography imaging of the test group implants prior to explantation shows a decrease in iodide volume and density over time. Explant analysis also indicates scaffold degradation. (Immuno)histochemistry shows comparable cellular contents and a similar neo‐tissue formation process for test and control group, demonstrating that the CA does not have apparent adverse effects. A supramolecular approach to create solid radiopaque biomaterials can therefore be used to noninvasively monitor the biodegradation of synthetic implants. 相似文献
18.
Erwin Hans Gerhard Wullink Mark van Houdenhoven Geert Kazemier 《European Journal of Operational Research》2008
We consider the robust surgery loading problem for a hospital’s operating theatre department, which concerns assigning surgeries and sufficient planned slack to operating room days. The objective is to maximize capacity utilization and minimize the risk of overtime, and thus cancelled patients. This research was performed in collaboration with the Erasmus MC, a large academic hospital in the Netherlands, which has also provided historical data for the experiments. We propose various constructive heuristics and local search methods that use statistical information on surgery durations to exploit the portfolio effect, and thereby to minimize the required slack. We demonstrate that our approach frees a lot of operating room capacity, which may be used to perform additional surgeries. Furthermore, we show that by combining advanced optimization techniques with extensive historical statistical records on surgery durations can significantly improve the operating room department utilization. 相似文献
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Neil S. Keddie Geert Bultynck Tomas Luyten Alexandra M.Z. Slawin Stuart J. Conway 《Tetrahedron: Asymmetry》2009,20(6-8):857-866
The synthesis of d-myo-inositol 1,4,5-trisphosphate (InsP3) from methyl α-d-glucopyranose, via a type 2 Ferrier rearrangement is reported. A key intermediate in this synthesis possesses orthogonal protecting groups at the 1-, 4- and 5-position, making it a versatile starting point for the synthesis of unnatural InsP3 derivatives. Biological evaluation of the synthetic InsP3 demonstrates that this compound evokes selective Ca2+ release via activation of InsP3 receptors. 相似文献