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991.
Several regularities of the accumulation of vacuum arc metal macroparticles (MP) on the sample on repetitively pulsed biasing (105 Hz, 7 µs, ?0.5 kV to ?3.5 kV) have been investigated. It has been shown that the substrate temperature plays a very important role in controlling the MP amounts on the sample. A possibility to change the metal particle number density on the substrate in the range from 105/cm2 to 107/cm2, depending on bias pulse parameters, sample temperature, and ion plasma saturation current density, has been demonstrated. The shape of MPs and their adhesion to the substrate surface depends strongly on the MP energy balance in a high-voltage space charge sheath. 相似文献
992.
Glioblastoma is the most frequent primary neoplasm of the central nervous system and still suffers from very poor therapeutic impact. No clear improvements over current standard of care have been made in the last decade. For other cancers, but also for brain metastasis, which harbors a very distinct biology from glioblastoma, immunotherapy has already proven its efficacy. Efforts have been pursued to allow glioblastoma patients to benefit from these new approaches, but the road is still long for broad application. Here, we aim to review key glioblastoma immune related characteristics, current immunotherapeutic strategies being explored, their potential caveats, and future directions. 相似文献
993.
Brouillet Thibaut; Ferrier Laurent P.; Grosselin Anne; Brouillet Denis 《Canadian Metallurgical Quarterly》2011,11(5):1202
Recent results from Cannon, Hayes, and Tipper (2010) have established that the Action Compatibility Effect (ACE) is hedonically marked and elicits a genuine positive reaction. In this work, we aim to show that the hedonic marking of the ACE has incidental consequences on affective judgment. For this, we used the affective priming paradigm principle (for a review, see Musch & Klauer, 2003): participants have to respond, as quickly as they can, regarding the pleasantness or unpleasantness character of a target word. In the priming phase, we do not present an affective stimulus; however, we present two different graspable objects, one after the other. The handles of the graspable objects are shown either both on the same side (i.e., perceptual action compatibility) or not (i.e., perceptual action incompatibility). In addition, the orientation of the handles of the objects are either compatible (i.e., action compatibility) or not (i.e., action compatibility) with the response hand used for the word evaluation. Consistent with our hypothesis, participants responded faster to positive words after perceptual action compatibility and action compatibility (thus demonstrating the ACE) than after incompatibility conditions. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
994.
It is widely accepted that low dimensionality of semiconductor heterostructures and nanostructures can significantly improve their thermoelectric efficiency. However, what is less well understood is the precise role of electronic and lattice transport coefficients in the improvement. We differentiate and analyze the electronic and lattice contributions to the enhancement by using a nearly parameter-free theory of the thermoelectric properties of semiconductor nanowires. By combining molecular dynamics, density functional theory, and Boltzmann transport theory methods, we provide a complete picture for the competing factors of thermoelectric figure of merit. As an example, we study the thermoelectric properties of ZnO and Si nanowires. We find that the figure of merit can be increased as much as 30 times in 8-Å-diameter ZnO nanowires and 20 times in 12-Å-diameter Si nanowires, compared with the bulk. Decoupling of thermoelectric contributions reveals that the reduction of lattice thermal conductivity is the predominant factor in the improvement of thermoelectric properties in nanowires. While the lattice contribution to the efficiency enhancement consistently becomes larger with decreasing size of nanowires, the electronic contribution is relatively small in ZnO and disadvantageous in Si. 相似文献
995.
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997.
Elif Tosun Denis Zorin 《Computer Aided Geometric Design》2011,28(1):1-22
We present a manifold-based surface construction extending the C∞ construction of Ying and Zorin (2004). Our surfaces allow for piecewise-smooth boundaries and have an improved derivative and visual behavior. Their degree of smoothness can be controlled by the user. Two-flexibility of our surface construction is confirmed numerically for a range of local mesh configurations. 相似文献
998.
The binary relation framework has been shown to be applicable to many real-life preference handling scenarios. Here we study preference contraction: the problem of discarding selected preferences. We argue that the property of minimality and the preservation of strict partial orders are crucial for contractions. Contractions can be further constrained by specifying which preferences should be protected. We consider preference relations that are finite or finitely representable using preference formulas. We present algorithms for computing minimal and preference-protecting minimal contractions for finite as well as finitely representable preference relations. We study relationships between preference change in the binary relation framework and belief change in the belief revision theory. We evaluate the proposed algorithms experimentally and present the results. 相似文献
999.
Alexander A. Artyukhov Mikhail I. Shtilman Andrey N. Kuskov Anna P. Fomina Denis E. Lisovyy Anna S. Golunova Aristidis M. Tsatsakis 《Journal of Polymer Research》2011,18(4):667-673
Macroporous polymeric hydrogels for the last several years have found broad application in areas connected with medicine,
especially in such new disciplines as cell and tissue engineering. In present work a novel combine approach is proposed for
preparation of polyvinyl alcohol macroporous hydrogels by cross-linking of polyvinyl alcohol acrylic derivatives in the presence
of heterophase of frozen aqueous media. Hydrogels prepared using this method does not need additional structure fixing and
are characterized by high thermal stability in swollen state sustaining even heating to more than 100 °С. The influence of
different factors and reaction conditions on the cross-linked hydrogel formation process was studied. The high yield of products
(80 ÷ 95%) was observed when reaction was conducted at temperature range −12 ÷ −18 °С, concentration of macromer 4–12 weight
%, and amount of initiator 0.8 ÷ 1.6 mg/ml. Moreover, the equilibrium swelling of synthesized macroporous hydrogels was investigated
and it was shown that synthesized cross-linked hydrogels are characterized by high water absorption which is weakly depended
on solution pH and ionic force values. 相似文献
1000.
Mathieu Renouf Philippe A. Guy Cynthia Marmet Anne‐Lise Fraering Karin Longet Julie Moulin Marc Enslen Denis Barron Fabiola Dionisi Christophe Cavin Gary Williamson Heike Steiling 《Molecular nutrition & food research》2010,54(6):760-766
Previous studies on coffee examined absorption of phenolic acids (PA) in the small intestine, but not the contribution of the colon to absorption. Nine healthy volunteers ingested instant soluble coffee (~335 mg total chlorogenic acids (CGAs)) in water. Blood samples were taken over 12 h, and at 24 h to assess return to baseline. Many previous studies, which used glucuronidase and sulfatase, measured only PA and did not rigorously assess CGAs. To improve this, plasma samples were analyzed after full hydrolysis by chlorogenate esterase, glucuronidase and sulfatase to release aglycone equivalents of PA followed by liquid–liquid extraction and ESI‐LC‐ESI‐MS/MS detection. Ferulic, caffeic and isoferulic acid equivalents appeared rapidly in plasma, peaking at 1–2 h. Dihydrocaffeic and dihydroferulic acids appeared in plasma 6–8 h after ingestion (Tmax=8–12 h). Substantial variability in maximum plasma concentration and Tmax was also observed between individuals. This study confirms that the small intestine is a significant site for absorption of PA, but shows for the first time that the colon/microflora play the major role in absorption and metabolism of CGAs and PA from coffee. 相似文献