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991.
Crecelius AC Cornett DS Caprioli RM Williams B Dawant BM Bodenheimer B 《Journal of the American Society for Mass Spectrometry》2005,16(7):1093-1099
We have developed a method to visualize matrix-assisted laser desorption ionization imaging mass spectrometry (MALDI IMS) data aligned with optically determinable tissue structures in three dimensions. Details of the methodology are exemplified using the 3-D reconstruction of myelin basic protein (MBP) in the corpus callosum of a mouse brain. In this procedure, optical images obtained from serial coronal sections are first aligned to each other to reconstruct a surface of the corpus callosum from segmented contours of the aligned images. The MALDI IMS data are then coregistered to the optical images and superimposed into the surface to create the final 3-D visualization. Correlating proteomic data with anatomical structures provides a more comprehensive understanding of healthy and pathological brain functions, and holds promise to be utilized in more complex anatomical arrangements. 相似文献
992.
Alberghina G Cozzolino R Fisichella S Garozzo D Savarino A 《Rapid communications in mass spectrometry : RCM》2005,19(14):2069-2074
The verification of the cDNA-deduced sequence of the high molecular weight glutenin subunit 1Bx7 in Chinese Spring cultivar was achieved by direct matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOFMS) analysis of the tryptic fragments. The published sequence of the 1Bx7 subunit contains 5 Lys and 15 Arg residues but, due to the presence of three Arg-Pro bonds, which are generally resistant to cleavage by trypsin, or cleaved to a very limited extent by trypsin, 19 peptides can be predicted. The identification of the tryptic fragments was achieved by direct MALDI-MS analysis by using three different matrices (DHB, SA and HCCA) in combination with the most compatible sample preparation procedures in order to obtain the maximum sequence coverage. MALDI analysis of the 1Bx7 tryptic digest resulted in the identification of the expected peptides and additional fragments arising from non-specific cleavages; the fragments that were not detected are peptides with low mass (from 147.2 to 317.4), so we obtained a sequence coverage of 98.8%. The results reported here also indicated that the sequence of the 1Bx7 subunit from cv. Chinese Spring is different from the cDNA-deduced sequence reported in the literature; in particular, a possible insertion of the hexapeptide QPGQGQ within the sequence Gln630-Tyr725 was suggested. Finally, it is possible to rule out glycosylation of the 1Bx7 subunit, or any other post-translational modification, to within the detection limits of the method. 相似文献
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996.
June?DongEmail author Ding?Zhang Hong?Yan Anna?Nagurney 《Annals of Operations Research》2005,135(1):155-178
In this paper, we present a supply chain network model with multiple tiers of decision-makers, consisting, respectively, of
manufacturers, distributors, and retailers, who can compete within a tier but may cooperate between tiers. We consider multicriteria
decision-making for both the manufacturers and the distributors whereas the retailers are subject to decision-making under
uncertainty since the demands associated with the product are random. We derive the optimality conditions for the decision-makers,
establish the equilibrium conditions, and derive the variational inequality formulation. We then utilize the variational inequality
formulation to provide both qualitative properties of the equilibrium product shipment, service level, and price pattern and
to propose a computational procedure, along with convergence results. This is the first supply chain network model to capture
both multicriteria decision-making and decision-making under uncertainty in an integrated equilibrium framework. 相似文献
997.
Anna?Dall’AcquaEmail author Guido?SweersEmail author 《Annali di Matematica Pura ed Applicata》2005,184(3):361-374
Hadamard claimed in 1907 that the clamped-plate equation is positivity preserving for domains which are bounded by a Limaçon de Pascal. We will show that this claim is false in its full generality. However, we will also prove that there are nonconvex limaçons for which the clamped-plate equation has the sign-preserving property. In fact we will give an explicit bound for the parameter of the limaçon where sign change may occur. Mathematics Subject Classification (2000) 35J40, 35Q72, 35B50 相似文献
998.
Paul Houston Ilaria Perugia Anna Schneebeli Dominik Schötzau 《Numerische Mathematik》2005,100(3):485-518
Summary In this paper, we introduce and analyze the interior penalty discontinuous Galerkin method for the numerical discretization of the indefinite time-harmonic Maxwell equations in the high-frequency regime. Based on suitable duality arguments, we derive a-priori error bounds in the energy norm and the L2-norm. In particular, the error in the energy norm is shown to converge with the optimal order (hmin{s,}) with respect to the mesh size h, the polynomial degree , and the regularity exponent s of the analytical solution. Under additional regularity assumptions, the L2-error is shown to converge with the optimal order (h+1). The theoretical results are confirmed in a series of numerical experiments.Supported by the EPSRC (Grant GR/R76615).Supported by the Swiss National Science Foundation under project 21-068126.02.Supported in part by the Natural Sciences and Engineering Council of Canada. 相似文献
999.
1J(13C13C) has been determined in naturally abundant samples of η1,η2 -alkenyl-η5 -cyclopentadienylnickel complexes; for the coordinated double bonds 1J(CC) lies between the value for free ethylene and cyclopropane, and therefore gives direct insight into the relevant bonding situation. 相似文献
1000.
Ewa Skrzypczak-Jankun Hanna Małuszyńska Anna Perkowska Zygmunt Kałuski 《Journal of chemical crystallography》1980,10(3-4):67-74
The formula of the title compound is C16H27ClN2O5,MW = 362.9 orthorhombic,P212121,a = 8.403(1),b= 13.133(1),c= 15.972(2) Å,Z = 4,D
x
= 1.37 g cm–3, (CuK) = 2.2 mm-1. The lupanine skeleton has atrans-trans configuration. The ringA has a half-chair conformation, theB andD rings adopt a chair form, and theC ring forms a boat. The lupanine cations are linked together by the intermolecular hydrogen bonds forming infinite chains alongb. The N(16) ... O(C2) distance is 2.763(7) Å. 相似文献