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排序方式: 共有406条查询结果,搜索用时 15 毫秒
61.
Beverly S Colley Melissa A Cavallin KC Biju David R Marks Debra A Fadool 《BMC neuroscience》2009,10(1):8
Background
Neurotrophins are important regulators of growth and regeneration, and acutely, they can modulate the activity of voltage-gated ion channels. Previously we have shown that acute brain-derived neurotrophic factor (BDNF) activation of neurotrophin receptor tyrosine kinase B (TrkB) suppresses the Shaker voltage-gated potassium channel (Kv1.3) via phosphorylation of multiple tyrosine residues in the N and C terminal aspects of the channel protein. It is not known how adaptor proteins, which lack catalytic activity, but interact with members of the neurotrophic signaling pathway, might scaffold with ion channels or modulate channel activity. 相似文献62.
Antonio L. Braga Ricardo S. Schwab Syed M. Salman Juliano B. Azeredo 《Tetrahedron letters》2009,50(20):2309-1982
A set of chiral β-seleno amines were prepared by the ring-opening reaction of unprotected aziridines. Under acid conditions diaryl or dialkyl diselenides were reduced by zinc and treated with unprotected aziridines to produce the desired products in good yields. Chiral β-telluro amine was also obtained using this method. 相似文献
63.
We consider the weakly singular boundary integral equation on a deterministic smooth closed curve with random loading g(ω). Given the kth order statistical moment of g, the aim is the efficient deterministic computation of the kth order statistical moment of u. We derive a deterministic formulation for the kth statistical moment. It is posed in the tensor product Sobolev space and involves the k-fold tensor product operator . The standard full tensor product Galerkin BEM requires unknowns for the kth moment problem, where N is the number of unknowns needed to discretize Γ. Extending ideas of [V.N. Temlyakov, Approximation of functions with bounded mixed derivative, Proc. Steklov Inst. Math. (1989) vi+121. A translation of Trudy Mat. Inst. Steklov 178 (1986)], we develop the p-Sparse Grid Galerkin BEM to reduce the number of unknowns from to . 相似文献
64.
Barnabás Bede Emil Daniel Schwab Hajime Nobuhara Imre J. Rudas 《International Journal of Approximate Reasoning》2009,50(1):21-36
Recently, it has been shown that sum and product are not the only operations that can be used in order to define concrete approximation operators. Several other operations provided by fuzzy sets theory can be used. In the present paper, pseudo-linear approximation operators are investigated from the practical point of view in Image Processing. We study max–min, max–product Shepard type approximation operators together with Shepard operators based on pseudo-operations generated by an increasing continuous generator. It is shown that in several cases these outperform classical approximation operators based on sum and product operations. 相似文献
65.
Kovaric BC Kokona B Schwab AD Twomey MA de Paula JC Fairman R 《Journal of the American Chemical Society》2006,128(13):4166-4167
The anionic porphyrin, meso-tetrakis(4-sulfonatophenyl)porphine, is found to tightly bind to an engineered 14-residue peptide, resulting in induced alpha-helix formation when mixed in aqueous solutions. The small porphyrin-peptide dissociation constant (2 muM) observed is related to the energetics of peptide helix formation coupled with electrostatic interactions between the anionic porphyrin and cationic residues in the coiled peptide. Analytical ultracentrifugation measurements indicate the porphyrin-peptide complexes dimerize, probably into a coiled coil, and weakly associate to form even higher order structures. 相似文献
66.
Schwab NV Porcari AM Coelho MB Schmidt EM Jara JL Visentainer JV Eberlin MN 《The Analyst》2012,137(11):2537-2540
An exceptionally easy to assemble source for ambient mass spectrometry is described. Based on Venturi easy ambient sonic-spray ionization (V-EASI), the source was further simplified by the use of a can of compressed air which simultaneously provides solution or solvent Venturi self-pumping and continuous, stable and abundant low-noise ion signal via voltage-free sonic-spraying. Further simplification was also attained by the use of inexpensive and readily commercially available parts: a surgical 2-way catheter, an aerosol can of compressed air, a 30 cm long fused-silica capillary and a hypodermic needle. This "Spartan" V-EASI source seems to offer one of the easiest and cheapest ways to make ions for ambient desorption/ionization mass spectrometry analysis of both liquid and solid samples. 相似文献
67.
D. Cortina-Gil T. Baumann H. Geissel H. Lenske K. Sümmerer L. Axelsson U. Bergmann M.J.G. Borge L.M. Fraile M. Hellström M. Ivanov N. Iwasa R. Janik B. Jonson K. Markenroth G. Münzenberg F. Nickel T. Nilsson A. Ozawa K. Riisager G. Schrieder W. Schwab H. Simon C. Scheidenberger B. Sitar T. Suzuki M. Winkler 《The European Physical Journal A - Hadrons and Nuclei》2001,10(1):49-56
One-neutron removal cross-sections ( ) of 17, 19C in various targets at about 900 MeV/nucleon, and one-proton removal cross-sections ( ) of 8, 10B at about 1400 MeV/nucleon were measured using the fragment separator FRS at GSI. A significant increase of for 19C compared to its neighbors was observed. The same behavior was found for for the neutron-deficient nucleus 8B compared to the stable isotope 10B. These results support a one-neutron halo structure in 19C and a one-proton halo in 8B.
Received: 26 July 2000 / Accepted: 11 January 2001 相似文献
68.
D. Brill P. Beckerle C. Bormann E. Schwab Y. Shin H. Ströbele P. Baltes C. Müntz H. Oeschler C. Sturm A. Wagner R. Barth M. Cieslak M. Dȩbowski E. Grosse P. Koczoń M. Mang D. Miśkowiec R. Schicker P. Senger B. Kohlmeyer F. Pühlhofer J. Speer K. Völkel W. Waluś 《Zeitschrift für Physik A Hadrons and Nuclei》1997,357(2):207-213
Triple differential cross-sections of midrapidity pions from 209Bi+209Bi collisions were measured with the Kaon Spectrometer at SIS at incident energies of 400, 700 and 1000 AMeV. The azimuthal emission pattern of the pions has been investigated in dependence of beam energy and impact parameter. An enhanced emission of pions perpendicular to the reaction plane is observed. The strength of the anisotropy increases with beam energy and pion transverse momentum. In contrast to the nucleons the anisotropy varies only little with the impact parameter. No difference in the behaviour of positive and negative pions is observed. 相似文献
69.
D. Reuter V. Stavarache A.D. Wieck M. Schwab R. Oulton M. Bayer 《Physica E: Low-dimensional Systems and Nanostructures》2006,32(1-2):73
We have performed single dot photoluminescence and time-resolved ensemble photoluminescence measurements on InAs quantum dots embedded in a lateral in-plane p–i–n or n–i–n device, respectively, which makes the application of lateral electric fields, i.e. field direction perpendicular to the growth direction, feasible. Time-resolved measurements show an increase in the radiative lifetime of up to 30% with increasing field. We attribute this to the reduced overlap between the electron and hole wave functions. Single dot spectroscopy revealed a small red-shift of the emission energies of maximum 0.5 meV. This shift can be explained by the quantum confined Stark effect taking into account that the red-shift due to the band-tilting is partly compensated by a decrease in exciton binding energy. 相似文献
70.