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排序方式: 共有1072条查询结果,搜索用时 15 毫秒
61.
62.
R Gomez L Dauwe H Haggerty E Malamud M Nikolic S Hagopian A Pifer R Abrams J Ares H Goldberg C Halliwell S Margulies D McLeod A Salminen J Solomon G Wu S Blessing R Crittenden P Draper A Dzierba R Heinz J Krider T Marshall J Martin A Sambamurti P Smith A Snyder C Stewart T Sulanke A Zieminski R Ellsworth J Goodman S Gupta G Yodh T Watts V Abramov Y Antipov B Baldin S Denisov V Glebov Y Gorin V Kryshkin A Petrukhin S Polovnikov R Sulyaev 《Canadian Metallurgical Quarterly》1987,35(9):2736-2746
63.
Revenue-collection data from toll roads allow for accurate estimates of miles driven by vehicle type and, when combined with crash data, valid estimates of crash involvements per mile driven. Data on vehicle-miles traveled and collisions were obtained from toll road authorities in Florida. Kansas, and New York. In addition, state crash files and published vehicle-miles of travel were obtained for toll roads in Illinois. Indiana, Ohio, and Pennsylvania. Large commercial motor vehicles were significantly underinvolved in single-vehicle crashes on all state toll roads. In five states, commercial motor vehicles were significantly overinvolved in multiple-vehicle crashes relative to passenger vehicles; the exceptions were Kansas, where they had significantly lower multiple-vehicle involvement rates, and Indiana. where there were no significant differences in multiple-vehicle involvements by vehicle type. The risk of commercial motor vehicle involvement in multiple-vehicle crashes resulting in deaths or serious injuries was double that of passenger vehicles in the two states (Ohio and Pennsylvania) that identified serious injuries. Whether crash rates, on toll roads of commercial motor vehicles are higher or lower than those of passenger vehicles appears to depend on the type of crash, specific toll road. and traffic density. 相似文献
64.
Quintanar L Stoj C Taylor AB Hart PJ Kosman DJ Solomon EI 《Accounts of chemical research》2007,40(6):445-452
Multicopper oxidases (MCOs) are encoded in the genomes of Eukarya, Bacteria, and Archea. These proteins are unique in that they contain at least four Cu atom prosthetic groups organized into one each of the three spectral classifications of copper sites in biology: type 1 (T1), type 2 (T2), and binuclear type 3 (T3), where the T2 and T3 sites form a trinuclear Cu cluster. With these four redox-active copper sites, the multicopper oxidases catalyze the four-electron (4e(-)) reduction of dioxygen to 2H2O, an activity that they alone share with the terminal heme-containing oxidases. Most MCOs exhibit broad specificity towards organic reductants, while a relatively small number of family members exhibit equally robust activity towards metal ions like Fe(II), Cu(I), and Mn(II) and, thus, are considered metallo-oxidases. This Account analyzes the structure-activity features of multicopper oxidases that determine their relative substrate specificity. Since the substrate oxidation step involves an outer-sphere electron transfer from the reductant to the T1Cu site in the protein, the concepts of Marcus theory are applied to unravel the origin of the substrate specificity of the multicopper ferroxidases. 相似文献
65.
KR Solomon EA Kurt-Jones RA Saladino AM Stack IF Dunn M Ferretti D Golenbock GR Fleisher RW Finberg 《Canadian Metallurgical Quarterly》1998,102(11):2019-2027
Septic shock induced by lipopolysaccharide (LPS) triggering of cytokine production from monocytes/macrophages is a major cause of morbidity and mortality. The major monocyte/macrophage LPS receptor is the glycosylphosphatidylinositol (GPI)-anchored glycoprotein CD14. Here we demonstrate that CD14 coimmunoprecipitates with Gi/Go heterotrimeric G proteins. Furthermore, we demonstrate that heterotrimeric G proteins specifically regulate CD14-mediated, LPS-induced mitogen-activated protein kinase (MAPK) activation and cytokine production in normal human monocytes and cultured cells. We report here that a G protein binding peptide protects rats from LPS-induced mortality, suggesting a functional linkage between a GPI-anchored receptor and the intracellular signaling molecules with which it is physically associated. 相似文献
66.
Monday Eze Charles Okunbor Deborah Aleburu Olubukola Adekola Ibrahim Ramon Nneka Richard-Nnabu Oghenetega Avwokuruaye Abisola Olayiwola Rume Yoro Esomu Solomon 《计算机系统科学与工程》2022,41(2):595-609
This work demonstrates in practical terms the evolutionary concepts and computational applications of Parametric Curves. Specific cases were drawn from higher order parametric Bezier curves of degrees 2 and above. Bezier curves find real life applications in diverse areas of Engineering and Computer Science, such as computer graphics, robotics, animations, virtual reality, among others. Some of the evolutionary issues explored in this work are in the areas of parametric equations derivations, proof of related theorems, first and second order calculus related computations, among others. A Practical case is demonstrated using a graphical design, physical hand sketching, and programmatic implementation of two opposite-faced handless cups, all evolved using quadratic Bezier curves. The actual drawing was realized using web graphics canvas programming based on HTML 5 and JavaScript. This work will no doubt find relevance in computational researches in the areas of graphics, web programming, automated theorem proofs, robotic motions, among others. 相似文献
67.
Shyla Joseph James T. Joseph Annamma John J. K. Thomas Sam Solomon 《Journal of Materials Science: Materials in Electronics》2011,22(7):741-744
LnTiSbxNb1−xO6 (Ln = Ce, Pr) ceramics were prepared by the conventional solid state ceramic route for x = 0, 0.05, 0.1, 0.15, 0.2 and 0.25.
The structure of the materials was analyzed using X-ray diffraction techniques. The cell parameters and the theoretical densities
of the samples were calculated using least square methods. The samples are sintered to more than 90% of the theoretical density
at 1,325–1,350 °C. The microwave dielectric properties were measured using the cavity resonator method. The surface morphology
of the sintered sample was analyzed using Scanning Electron Microscopy. All the materials have good microwave dielectric properties
and are suitable for dielectric resonator applications. 相似文献
68.
Solomon Guadie Worku Chunxiang XuAuthor VitaeJining ZhaoAuthor Vitae Xiaohu HeAuthor Vitae 《Computers & Electrical Engineering》2014
Cloud computing poses many challenges on integrity and privacy of users’ data though it brings an easy, cost-effective and reliable way of data management. Hence, secure and efficient methods are needed to ensure integrity and privacy of data stored at the cloud. Wang et al. proposed a privacy-preserving public auditing protocol in 2010 but it is seriously insecure. Their scheme is vulnerable to attacks from malicious cloud server and outside attackers regarding to storage correctness. So they proposed a scheme in 2011 with an improved security guarantee but it is not efficient. Thus, in this paper, we proposed a scheme which is secure and with better efficiency. It is a public auditing scheme with third party auditor (TPA), who performs data auditing on behalf of user(s). With detail security analysis, our scheme is proved secure in the random oracle model and our performance analysis shows the scheme is efficient. 相似文献
69.
Surface expression of the T cell antigen receptor (TCR) in mature T cells requires the association of a variable heterodimer (alpha.beta or gamma.delta) with six invariant CD3 polypeptides (gamma, delta, epsilon-epsilon, zeta-zeta, or zeta-eta). We described here that deletion of the cytoplasmic tail polypeptide sequence (Lys-Lys-Lys-Asn-Ser) of TCR beta-chain (beta CT) results in expression of the truncated beta-chain on the surface of a mature T cell hybridoma line, in the absence of TCR-alpha, as a glycophosphatidylinositol (GPI)-anchored monomeric polypeptide. The GPI-anchored TCR-beta CT is not associated with CD3-epsilon and is incapable of conventional signal transduction. Association with TCR-alpha prevents beta CT from GPI-linkage formation. The alpha beta CT heterodimer binds the CD3 polypeptides, and the resultant TCR alpha beta CT/CD3 complex is capable of signal transduction. Our data show that a signal sequence for GPI-linkage formation is present in TCR-beta, and this alternative membrane anchoring mechanism can be utilized by beta-chain polypeptide lacking the CT sequence. We conclude therefore that in the absence of TCR-alpha expression, the beta-chain CT sequence plays an essential function in hindering GPI-linkage formation, thereby preventing escape of incompletely assembled TCR beta-chain to the cell surface of mature T cells. 相似文献
70.
Noam Ben-Eliezer Eddy Solomon Elad Harel Nava Nevo Lucio Frydman 《Magma (New York, N.Y.)》2012,25(6):433-442