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61.
Distinctive MS/MS Fragmentation Pathways of Glycopeptide‐Generated Oxonium Ions Provide Evidence of the Glycan Structure
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Jin Yu Manuel Schorlemer Alejandro Gomez Toledo Christian Pett Dr. Carina Sihlbom Prof. Göran Larson Dr. Ulrika Westerlind Dr. Jonas Nilsson 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(3):1114-1124
Post‐translational glycosylation of proteins play key roles in cellular processes and the site‐specific characterisation of glycan structures is critical to understanding these events. Given the challenges regarding identification of glycan isomers, glycoproteomic studies generally rely on the assumption of conserved biosynthetic pathways. However, in a recent study, we found characteristically different HexNAc oxonium ion fragmentation patterns that depend on glycan structure. Such patterns could be used to distinguish between glycopeptide structural isomers. To acquire a mechanistic insight, deuterium‐labelled glycopeptides were prepared and analysed. We found that the HexNAc‐derived m/z 126 and 144 oxonium ions, differing in mass by H2O, had completely different structures and that high‐mannose N‐glycopeptides generated abundant Hex‐derived oxonium ions. We describe the oxonium ion decomposition mechanisms and the relative abundance of oxonium ions as a function of collision energy for a number of well‐defined glycan structures, which provide important information for future glycoproteomic studies. 相似文献
62.
A well-known result for Vilenkin systems is the fact that for all 1 p ∞ the n-th partial sums of Fourier series of all functions in the space Lpconverge to the function in Lp-norm.This statement can not be generalized to any representative product system on the complete product of finite non-abelian groups,but even then it is true for the complete product of quaternion groups with bounded orders and monomial representative product system ordered in a specific way. 相似文献
63.
M. J. Cánovas A. Hantoute J. Parra F. J. Toledo 《Journal of Optimization Theory and Applications》2014,160(1):111-126
This paper characterizes the calmness property of the argmin mapping in the framework of linear semi-infinite optimization problems under canonical perturbations; i.e., continuous perturbations of the right-hand side of the constraints (inequalities) together with perturbations of the objective function coefficient vector. This characterization is new for semi-infinite problems without requiring uniqueness of minimizers. For ordinary (finitely constrained) linear programs, the calmness of the argmin mapping always holds, since its graph is piecewise polyhedral (as a consequence of a classical result by Robinson). Moreover, the so-called isolated calmness (corresponding to the case of unique optimal solution for the nominal problem) has been previously characterized. As a key tool in this paper, we appeal to a certain supremum function associated with our nominal problem, not involving problems in a neighborhood, which is related to (sub)level sets. The main result establishes that, under Slater constraint qualification, perturbations of the objective function are negligible when characterizing the calmness of the argmin mapping. This result also states that the calmness of the argmin mapping is equivalent to the calmness of the level set mapping. 相似文献
64.
Alex Neves Junior Romildo Dias Toledo Filho Eduardo de Moraes Rego Fairbairn Jo Dweck 《Journal of Thermal Analysis and Calorimetry》2013,113(3):1577-1584
During the formation of pastes, mortar and concretes have been used to capture CO2. This work presents a methodology to estimate the carbon dioxide (CO2) sequestered by high strength and sulfate-resistant Portland cement pastes during their early stages of hydration, by Thermogravimetry and Derivative Thermogravimetry. Water to cement ratio equal to 0.50 and 0.70 were evaluated and the captured CO2 amount was determined through TG/DTG curve data on initial cement mass basis, obtained during accelerated carbonation from the fluid state and accelerated carbonation after a first hydration process. The experiments were performed in a controlled chamber, maintaining the CO2 content at 20 vol % and the temperature at 25 °C, at different relative humidity (RH) (60 and 80 %) ambient. The procedure allows one to estimate the amount of CO2 sequestered by the initial cement mass of a given volume of paste, as well as to evaluate the RH and W/C ratio influence on the amount of hydrated formed products, mainly on the Ca(OH)2, important for CO2 fixation. 相似文献
65.
A new accurate finite‐difference (AFD) numerical method is developed specifically for solving high‐order Boussinesq (HOB) equations. The method solves the water‐wave flow with much higher accuracy compared to the standard finite‐difference (SFD) method for the same computer resources. It is first developed for linear water waves and then for the nonlinear problem. It is presented for a horizontal bottom, but can be used for variable depth as well. The method can be developed for other equations as long as they use Padé approximation, for example extensions of the parabolic equation for acoustic wave problems. Finally, the results of the new method and the SFD method are compared with the accurate solution for nonlinear progressive waves over a horizontal bottom that is found using the stream function theory. The agreement of the AFD to the accurate solution is found to be excellent compared to the SFD solution. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
66.
We discuss a technical problem arising in the motion planning algorithm of Kedem and Sharir [KS], and propose a way to overcome
it without increasing the asymptotic complexity of the algorithm
The first author was supported by the Eshkol Grant 04601-90 from the Israeli Ministry of Science and Technology. The second
author was partly supported by the Fund for Basic Research administered by the Israeli Academy of Sciences, by National Science
Foundation Grants CCR-91-22103 and CCR-93-11127, and by grants from the U.S.-Israeli Binational Science Foundation, and the
G.I.F., the German-Israeli Foundation for Scientific Research and Development. The third author was partly supported by the
Interdisciplinary Program at Tel-Aviv University. The third author’s current address is: Department of Computer Science, MIT,
Boston, MA, USA. 相似文献
67.
M. Schrader A. Szanto de Toledo H. V. Klapdor 《Zeitschrift für Physik A Hadrons and Nuclei》1979,289(2):193-196
A new method of identifying high-spin states at high excitation energies is presented. 相似文献
68.
69.
Wei Zhang Liban Jirmo Samira Toledo‐Roy Prof. John C. Hershberger Jocelyn M. Macho Prof. Alexander J. Grenning 《Angewandte Chemie (International ed. in English)》2016,55(51):15792-15796
Oxygenated, polycyclic terpenoid natural products have important biological activities. Although total synthesis of such terpenes is widely studied, synthetic strategies that allow for controlled placement of oxygen atoms and other functionality remains a challenge. Herein, we present a simple, scalable, and tunable synthetic strategy to assemble terpenoid‐like polycycloalkanes from cycloalkanones, malononitrile, and allylic electrophiles, abundantly available reagent classes. 相似文献
70.
M. J. Cánovas R. Henrion J. Parra F. J. Toledo 《Set-Valued and Variational Analysis》2016,24(4):565-579
This paper introduces the concept of critical objective size associated with a linear program in order to provide operative point-based formulas (only involving the nominal data, and not data in a neighborhood) for computing or estimating the calmness modulus of the optimal set (argmin) mapping under uniqueness of nominal optimal solution and perturbations of all coefficients. Our starting point is an upper bound on this modulus given in Cánovas et al. (4). In this paper we prove that this upper bound is attained if and only if the norm of the objective function coefficient vector is less than or equal to the critical objective size. This concept also allows us to obtain operative lower bounds on the calmness modulus. We analyze in detail an illustrative example in order to explore some strategies that can improve the referred upper and lower bounds. 相似文献