Software utilities for the interpretation of mass spectrometric data of glycoconjugates: application to glycosphingolipids of human serum

Glycosphingolipids (GSLs) are major components of the outer leaflet of the cell membrane. These lipids are involved in many cell surface events and show disease‐related expression changes. GSLs could thus serve as useful targets for biomarker discovery. The GSL structure is characterized by two entities: a hydrophilic glycan and a hydrophobic ceramide moiety. Both components exhibit numerous structural variations, the combination of which results in a large diversity of GSL structures that can potentially exist. Mass spectrometry (MS) is a powerful tool for high‐throughput analysis of GSL expression analysis and structural elucidation. Yet, the assignment of GSL structures using MS data is tedious and demands highly specialized expertise. SysBioWare, a software platform developed for MS data evaluation in glycomics, was here applied for the MS analysis of human serum GSLs. The program was tuned to provide automated compositional assignment, supporting a variety of glycan and ceramide structures. Upon in silico fragmentation, the masses of predicted ions arising from cleavages in the glycan as well as the ceramide moiety were calculated, thus enabling structural characterization of both entities. Validation of proposed structures was achieved by matching in silico calculated fragment ions with those of experimental MS/MS data. These results indicate that SysBioWare can facilitate data interpretation and, furthermore, help the user to deal with large sets of data by supporting management of MS and non‐MS data. SysBioWare has the potential to be a powerful tool for high‐throughput glycosphingolipidomics in clinical applications. Copyright © 2010 John Wiley & Sons, Ltd.     

A New Class of Kernels Leading to an Arbitrary Decay in Viscoelasticity

A new assumption on the relaxation in a viscoelastic problem ensuring uniform stability in an arbitrary rate is established. This assumption replaces a usual condition and allows for a much wider class of kernels. As consequences several earlier results are extended and improved.     

Perturbation theory in a framework of iteration methods

In a previous paper [J. Phys. A 36 (2003) 11807], we introduced the ‘asymptotic iteration method’ for solving second-order homogeneous linear differential equations. In this Letter, we study perturbed problems in quantum mechanics and we use the method to find the coefficients in the perturbation series for the eigenvalues and eigenfunctions directly, without first solving the unperturbed problem.     

An Optimal Diversification Network Model with Fixed-Solution Universe Subsets

This paper develops a generalized dynamic network model for portfolio investment diversification. The model considers the situation of the fixed solution subset corresponding to a fixed single-resource economic investment such as that found in many oil-producing nations. Quadratic side constraints on the variance of the resultant flow distribution are added to the model to accommodate uncertainty. The model has been tested using a prototype example. The results indicate that the risk associated with a single-resource investment can be reduced by determining optimal investment weights.     

DPSM technique for ultrasonic field modelling near fluid-solid interface

Distributed point source method (DPSM) is gradually gaining popularity in the field of non-destructive evaluation (NDE). DPSM is a semi-analytical technique that can be used to calculate the ultrasonic fields produced by transducers of finite dimension placed in homogeneous or non-homogeneous media. This technique has been already used to model ultrasonic fields in homogeneous and multi-layered fluid structures. In this paper the method is extended to model the ultrasonic fields generated in both fluid and solid media near a fluid-solid interface when the transducer is placed in the fluid half-space near the interface. Most results in this paper are generated by the newly developed DPSM technique that requires matrix inversion. This technique is identified as the matrix inversion based DPSM technique. Some of these results are compared with the results produced by the Rayleigh-Sommerfield integral based DPSM technique. Theory behind both matrix inversion based and Rayleigh-Sommerfield integral based DPSM techniques is presented in this paper. The matrix inversion based DPSM technique is found to be very efficient for computing the ultrasonic field in non-homogeneous materials. One objective of this study is to model ultrasonic fields in both solids and fluids generated by the leaky Rayleigh wave when finite size transducers are inclined at Rayleigh critical angles. This phenomenon has been correctly modelled by the technique. It should be mentioned here that techniques based on paraxial assumptions fail to model the critical reflection phenomenon. Other advantages of the DPSM technique compared to the currently available techniques for transducer radiation modelling are discussed in the paper under Introduction.     

Bacilli as Biological Nano-factories Intended for Synthesis of Silver Nanoparticles and Its Application in Human Welfare

The search of eco-friendly technologies for nano-synthesis is significant to expand their applications in human welfare. Nowadays, various inorganic nanoparticles with beneficial features have been synthesized via physical, chemical, and biological means. Significant biological applications of silver nanoparticles include on-infectious microbes, target drug delivery, cancer and vector-borne disease control. Their syntheses have been tested from plant fungi, bacteria, and viruses. The bacterial mediated synthesis of silver, gold, zinc and other metal leads to a milestone in nano-medicines. Thus, in this review, we focus on the contribution of Bacilli in the synthesis of silver nanoparticles, the mechanism of action and their potential application in the welfare of human beings.     

Influence of Differential Diffusion on Super-Equilibrium Temperature in Turbulent Non-Premixed Hydrogen/Air Flames

In this paper we wish to investigate the occurrence of super-equilibrium temperature values, observed in many experimental configurations. We would like to understand the origin of this phenomenon. Previous authors have already shown that differential diffusion can lead to considerable changes in the temperature field and we would like to build on top of this observation. We investigate numerically super-equilibrium combustion by considering both laminar counter-flow and turbulent diluted hydrogen/air diffusion flames. These turbulent flames are computed using direct numerical simulations (DNS). A detailed reaction mechanism is employed and the transport properties are modeled using multicomponent diffusion velocities, including the Soret effect. Analyzing these results we introduce three complementary parameters (dilution-free mixture fraction, dilution excess and local enthalpy) to describe the local combustion conditions. Introducing a measure of dilution separately from the mixture fraction is necessary for a proper analysis. Using this set of parameters it becomes possible to explain super-equilibrium temperature levels as a consequence of differential diffusion.     

An exact algorithm for the sequential ordering problem and its application to switching energy minimization in compilers

This article presents an exact algorithm for the precedence-constrained traveling salesman problem, which is also known as the sequential ordering problem. This NP-hard problem has applications in various domains, including operational research and compilers. In this article, the problem is presented and solved in the context of minimizing switching energy in compilers. Most previous work on minimizing switching energy in the compiler domain has been limited to simple heuristics that are not guaranteed to give an optimal solution. In this work, we present an exact algorithm for solving the switching energy minimization problem using a branch-and-bound approach. The proposed algorithm is simple and intuitive, yet powerful. It is the first exact algorithm for the switching energy problem that is shown to solve real instances of the problem within a few seconds per instance. Compared to previous work in the operational research domain, the proposed algorithm is believed to be the most powerful exact algorithm that does not require a linear programming formulation. The proposed algorithm is experimentally evaluated using instances taken from a production compiler. The results show that with a time limit of 10 ms per node, the proposed algorithm optimally solves 99.8 % of the instances. It optimally solves instances with up to 598 nodes within a few seconds. The resulting switching cost is 16 % less than that produced without energy awareness and 5 % less than that produced by a commonly used heuristic.     

Vilsmeier Reagent: An Efficient Reagent for the Transformation of 2-Aminobenzamides into Quinazolin-4(3H)-one Derivatives

Clean and easy preparation of quinazolin-4(3H)-one derivatives using 2-aminobenzamides and Vilsmeier reagent is described. 2-Aminobenzamides were converted into the corresponding quinazolinones under mild and efficient conditions, in good yields without undesirable by-products.

[Supplementary materials are available for this article. Go to the publisher's online edition of Synthetic Communications® for the following free supplemental resource(s): Full experimental and spectral details.]