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991.
992.
Leigh Irene W.; Powers Laurie; Vash Carolyn; Nettles Reginald 《Canadian Metallurgical Quarterly》2004,49(1):48
Objective: To identify barriers to, strategies for, and supports for psychological services for clients with disabilities. Design: Mail survey. Participants: Four hundred eighty-one psychologists who were American Psychological Association members. Measure: A survey that ascertained psychologists' perceptions of access barriers, success factors, and support needs in providing services to clients with disabilities, as well as experiences with bias or sensitivity. Results: Barriers to service provision include funding, accessibility, lack of provider knowledge, limited training in disability issues and services, and lack of sensitivity. Conclusions: Additional training for psychologists in disability issues, legal requirements regarding public accommodations, and disability resources is needed. Psychologists with disabilities may be an important resource. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
993.
Weber Irene T.; Harrison Robert W. 《Protein engineering, design & selection : PEDS》1999,12(6):469-474
Drug-resistant mutants of HIV-1 protease limit the long-termeffectiveness of current anti-viral therapy. In order to studydrug resistance, the wild-type HIV-1 protease and the mutantsR8Q, V32I, M46I, V82A, V82I, V82F, I84V, V32I/I84V and M46I/I84Vwere modeled with the inhibitors saquinavir and indinavir usingthe program AMMP. A new screen term was introduced to reproducemore correctly the electron distribution of atoms. The atomicpartial charge was represented as a delocalized charge distributioninstead of a point charge. The calculated proteasesaquinavirinteraction energies showed the highly significant correlationof 0.79 with free energy differences derived from the measuredinhibition constants for all 10 models. Three different protonationstates of indinavir were evaluated. The best indinavir modelincluded a sulfate and gave a correlation coefficient of 0.68between the calculated interaction energies and free energiesfrom inhibition constants for nine models. The exception wasR8Q with indinavir, probably due to differences in the solvationenergy. No significant correlation was found using the standardmolecular mechanics terms. The incorporation of the new screencorrection resulted in better prediction of the effects of inhibitorson resistant protease variants and has potential for selectingmore effective inhibitors for resistant virus. 相似文献
994.
In the present work results about roughness evolution along a polishing operation with corundum disks of size Norton 400 are presented. Hardened steel and hardened stainless steel samples were previously subjected to ball-end milling or side milling with cylindrical tool at different cutting conditions. Roughness height parameters Ra and Rt, as well as parameters related to the Abbott-Firestone curve such as Rk, Rpk, and Rvk, and shape parameters such as Rsk and Rku were studied. It is usually considered that a polishing operation is complete when Ra does not decrease significantly with more polishing time. In the present paper, an alternative method for determining the end of a polishing test is presented. Roughness is measured both in the longitudinal and in the transversal direction with respect to cutting marks, and it is assumed that the polishing operation is finished when longitudinal values equal transversal values, provided that from that moment on roughness values do not decrease significantly. Moreover, it is recommended to measure parameter Rvk in addition to or even instead of Ra, in order to obtain information about the presence of valleys from the previous milling operation. 相似文献
995.
996.
Blake Regan Alireza Aghajamali Johannes Froech Toan Trong Tran John Scott James Bishop Irene Suarez-Martinez Ying Liu Julie M. Cairney Nigel A Marks Milos Toth Igor Aharonovich 《Advanced materials (Deerfield Beach, Fla.)》2020,32(9):1906458
Diamond is known to possess a range of extraordinary properties that include exceptional mechanical stability. In this work, it is demonstrated that nanoscale diamond pillars can undergo not only elastic deformation (and brittle fracture), but also a new form of plastic deformation that depends critically on the nanopillar dimensions and crystallographic orientation of the diamond. The plastic deformation can be explained by the emergence of an ordered allotrope of carbon that is termed O8-carbon. The new phase is predicted by simulations of the deformation dynamics, which show how the sp3 bonds of (001)-oriented diamond restructure into O8-carbon in localized regions of deforming diamond nanopillars. The results demonstrate unprecedented mechanical behavior of diamond, and provide important insights into deformation dynamics of nanostructured materials. 相似文献
997.
998.
Munasur AP Pillay V Choonara YE Mackraj I Govender T 《Drug development and industrial pharmacy》2008,34(2):189-198
The aims were to compare the mucoadhesivity, controlled release properties, and release mechanisms of several polymeric systems of propranolol buccal tablets and to propose polymer(s) for formulation optimization. Mucoadhesivity differences in the polymer ranking between compacts and tablets were found. Mathematical models that best described the matrices were power law or a combination of the power law and Hopfenberg models. Poly acrylic acid (PAA), carboxymethyl cellulose (CMC), and poly ethylene glycol (PEG) in combination, were identified as suitable polymers for formulation optimization of a multipolymeric propranolol buccal tablet. Artificial neural networks were employed as a confirmatory approach to explicate that the selected polymers, in particular PAA, produced the most significant effect on the mean dissolution time and mucoadhesivity. 相似文献
999.
Annunziata M Guida L Perillo L Aversa R Passaro I Oliva A 《Journal of materials science. Materials in medicine》2008,19(12):3585-3591
Titanium nitride (TiN) coating has been proposed as an adjunctive surface treatment aimed to increase the physico-mechanical
and aesthetic properties of dental implants. In this study we investigated the biological response of primary human bone marrow
stromal cells (BMSC) to TiN-coated sandblasted (TiN-SB) compared to uncoated sandblasted (SB) surfaces. SB and TiN-SB disks
were qualitatively and quantitatively analyzed by atomic force microscopy. BMSC were obtained from healthy donors and their
adhesion and proliferation on the titanium disks were evaluated by scanning electron microscopy and viability assay. The osteoblastic
differentiation, in terms of alkaline phosphatase activity, osteocalcin synthesis, and extracellular mineralization, was assessed
by specific immunoenzymatic or spectrophotometric assays. No difference (P > 0.05) between TiN-SB and SB disks was found in terms of any of the investigated parameters. TiN-coating showed to maintain
the topographical characteristics of sandblasted titanium surfaces and their biological affinity toward bone precursors. 相似文献
1000.