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991.
YJ Geng Y Ishikawa DE Vatner TE Wagner SP Bishop SF Vatner CJ Homcy 《Canadian Metallurgical Quarterly》1999,84(1):34-42
We examined the potential involvement of two CC chemokine receptors (CCRs), CCR-1 and CCR-3, in the functional activation of granulocyte-macrophage colony-stimulating factor (GM-CSF) plus interleukin-4 (IL-4)-generated human peripheral blood monocyte-derived immature dendritic cells (DCs). Flow cytometric analysis showed that CCR-1, CCR-3, CCR-5, and CXC chemokine receptor (CXCR)-4 were expressed on the cell surface of monocyte-derived DCs. Treatment with a monoclonal antibody (MoAb) to either CCR-1 or CCR-3 but not MoAbs to CCR-5 and CXCR-4 abolished chemotactic migration of monocyte-derived DCs. The DCs treated with either the anti-CCR-1 MoAb or anti-CCR-3 MoAb were less efficient than untreated DCs in proliferation of allogeneic T cells (TCs) and TC-derived secretion of interferon-gamma (IFN-gamma). The homotypic aggregation of DCs and heterotypic aggregation of DCs with TCs were suppressed by the anti-CCR-1 MoAb or anti-CCR-3 MoAb. These results indicate that CCR-1 and CCR-3 specifically regulate interaction of TCs and DCs in the process of antigen presentation. 相似文献
992.
Christie Daniel J.; Tint Barbara S.; Wagner Richard V.; Winter Deborah DuNann 《Canadian Metallurgical Quarterly》2008,63(6):540
Although the literature in peace psychology has been growing rapidly, many American psychologists are unaware of how conflict is resolved and peace is conceptualized and achieved. This article reviews the long history and broadening scope of peace psychology and introduces a model of peace that is useful for organizing the literature. The model suggests that peace can be facilitated at four different points of intervention. The authors discuss relationships between positive and negative peace, structural and direct violence, and peacekeeping, peacemaking, and peacebuilding. They advance some challenges for peace psychologists and conclude that peace psychology is a crucial field for grappling with humanity's most pressing problems in the coming decades. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
993.
Brenda J. Little Patricia Wagner James S. Maki Marianne Walch Ralph Mitchell 《The Journal of Adhesion》2013,89(3):187-210
Starvation, growth phase, and carbon source influenced bacterial cell surface hydrophobicity. Both the number and kind of microorganisms that colonized metal surfaces depended on the type of metal and the presence of an imposed electrical potential. No significant differences in attachment and growth of a pure culture were observed when metal surfaces were dipped in an exogenous energy source. The chemical composition of naturally occurring adsorbed organic films on metal surfaces was shown to be independent of surface composition and polarization. 相似文献
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Ohne Zusammenfassung 相似文献
997.
Bhattacharya R. Wagner S. Tung Y.-J. Esler J.R. Hack M. 《Proceedings of the IEEE. Institute of Electrical and Electronics Engineers》2005,93(7):1273-1280
We fabricated an array of organic LED (OLED) pixels on a dome of clear polymer foil. The array is first formed on the flat polymer substrate and then is shaped to the dome. During the shaping process, the polymer substrate and the metal interconnect undergo plastic deformation while the OLED pixels remain intact. The OLED pixels have comparable I-V characteristics before and after deformation, but the luminous efficiency was reduced by the deformation, apparently as a consequence of fractures in the aluminum cathode. The demonstration of OLED displays on a spherical surface is an important advance in the fabrication of conformally shaped electronics. 相似文献
998.
Maalolan Ramanujam Renate Mix Manfred Wagner 《Journal of Adhesion Science and Technology》2013,27(16):1828-1839
For simulation and acceleration of artificial polymer ageing, polyolefin foils were exposed to low-pressure Ar plasma. Plasma particle bombardment and irradiation induce C–C and C–H bond scissions by σ?→?σ ? excitations on the surface and in near-surface layers. Consequently, radicals are generated. They react by recombination, cross-linking, metastable trapping of the radical site or formation of olefinic double bonds. The long-living and metastable trapped C-radicals as well as double bonds in polyolefins were immediately exposed to bromine vapour without breaking the vacuum after switching-off the plasma. These reactive sites rapidly react with the molecular bromine under formation of C–Br bonds. For 5?min of argon plasma exposure, the elemental concentration of bromine was 13% for polyethylene and 22% Br/C for polypropylene as analysed by X-ray photoelectron spectroscopy. Nevertheless, not all C radical sites have reacted with bromine. Later on, when the polyolefins brought in contact with ambient air, an additional post-plasma reaction of the remaining trapped radicals with oxygen was observed. The oxygen concentrations were lower after bromine gassing, thus repressing partially the post-plasma oxidation in the analysed layer (ca. 6?nm) by radical quenching. Such bromination took place either at the surface or in near-surface layers because the Attenuated Total Reflectance (ATR)-FTIR spectra (sampling depth ca. 2500?nm) did not show significant changes for argon plasma-treated PE foils with and without bromine vapour exposure. Further addition of bromine may also occur on C=C double bonds. 相似文献
999.
Over the past five years, we have been developing a Web-based, resource-bounded, information-gathering agent-called BIG, for Bounded Information Gathering-to support a human decision process. Although its techniques are general enough to apply to a wide range of domains, BIG specifically helps clients pick software packages. For example, a client can instruct BIG to recommend a database package for Windows 98 and specify constraints on both the search process and the product characteristics. BIG will then formulate a plan, locate and extract relevant information from both structured and unstructured documents, and return a recommendation to the client, along with supporting data. Our focus is on a recently developed capability, namely, to schedule information-gathering activity in a way that controls the money spent on acquiring information from sites that charge a fee for access. This capability supports an information marketplace on the Web, which we feel will eventually supersede (but obviously not completely replace) the current model of free information access supported by advertising fees 相似文献
1000.
Electric power generation systems require continuous monitoring to ensure safe and reliable operation. The data available from plant sensors supplied to the control systems may also be analyzed to verify proper operation and predict future behavior. In this paper, a combined cycle electric power plant has been monitored using limit and trend checking, reconstructed phase planes, and regression curves for transient and steady-state power generation. Representative experimental results are presented and discussed to illustrate the strengths of the proposed analysis strategies on a 510 MW combined-cycle system and a 180 MW steam turbine. The phase space analysis provides a means of visual inspection of operational anomalies and also offers a context for numerical analysis of the anomalous behavior. The statistical prognostic method provided regression errors below 2.0% for two of the three proposed plant signal combinations. However, all signal combinations offered the opportunity for system monitoring and diagnosis in terms of threshold violations which varied from 2.7% to 5.4% for these two signal sets. Overall, the monitoring strategies exhibited great promise for power generation system applications and merit further study. 相似文献