Search results for "termini"

First principles calculations of oxygen reduction reaction at fuel cell cathodes

2020

This study was partly supported by M-ERA-NET project SunToChem (EK, YM). The computer resources were provided by Stuttgart Super-computing Center (Project DEFTD 12939). Authors thank E. Heifets, M. M. Kuklja, M. Arrigoni, D. Morgan, R. Evarestov, and D. Gryaznov for fruitful discussions.

New insight on the lithium hydride–water vapor reaction system

2018

Abstract The reaction of lithium hydride (LiH) powder with pure water vapor (H2O and D2O) was studied by thermogravimetry and in situ infrared spectroscopy at 298 K over a large pressure range. The mean particle size of LiH is around 27 μm. At very low pressure, the hydrolysis starts with the formation of lithium oxide (Li2O). Then, both Li2O and lithium hydroxide (LiOH) are formed on increasing pressure, thus, creating a Li2O/LiOH bilayer. The reaction takes place through the consumption of LiH and the formation of Li2O at the LiH/Li2O interface and through the consumption of Li2O and the formation of LiOH at the Li2O/LiOH interface. Above 10 hPa, only the monohydrate LiOH·H2O is formed. T…

Surface termination effects on the oxygen reduction reaction rate at fuel cell cathodes

2018

This research was partly funded by the Latvian project IMIS2 with the computer resources provided by the High Performance Computing Centre Stuttgart (HLRS) (Project DEFTD 12939). The authors thank D. Gryaznov for fruitful discussions and M. Sokolov for technical assistance. MMK is grateful to the Office of the Director of National Science Foundation for support under the Independent Research and Development program. The ndings, conclusions, and recommendations expressed in this material are those of the authors and do not necessarily reect the views of NSF and other funding agencies.

Improved assessment of T-cell receptor (TCR) VB repertoire in clinical specimens: combination of TCR-CDR3 spectratyping with flow cytometry-based TCR…

2002

ABSTRACTAntigen-specific T-cell responses may be described by combining three categories: (i) the specificity and effector functions of a T-cell population, (ii) the quantity of T-cell responses (i.e., the number of responding T cells within the CD4/CD8 population), and (iii) the “quality” of T cells (defined by the T-cell receptor [TCR] structure). Several methods to measure T-cell responses are now available including evaluation of T-cell precursors using limiting dilution, the enzyme-linked immunospot assay, ex vivo TCR variable (v)-segment analysis determined by flow cytometry, and TCR-CDR3 length analysis (spectratyping), as well as identification of peptide-specific T cells using majo…

The role of positive selection in hepatitis C virus

2008

Hepatitis C virus (HCV) is a major health problem worldwide, infecting an estimated 170 million people. In this study, we have employed a large data set of sequences (14,654 sequences from between 25 and 100 clone sequences per analyzed region and per patient) from 67 patients infected with HCV genotype 1 (23 subtype 1a and 44 subtype 1b). For all patients, a sample prior to combined therapy with alpha interferon plus ribavirin was available, whereas for some patients additional samples after 6 or 12 months of treatment were also available. Twenty-seven patients responded to treatment (12 subtype 1a and 15 subtype 1b) and forty patients did not respond to treatment (11 subtype 1a vs. 29 sub…

Using evolutionary tools to refine the new hypervariable region 3 within the envelope 2 protein of hepatitis C virus

2007

Abstract The envelope 2 protein of hepatitis C virus (HCV) presents three hypervariable regions, named HVR1, HVR2 and HVR3, in which the presence of antigenic sites has been described. Genetic variability in these regions may reflect the generation of escape mutants as a consequence of the immune response. Therefore, these regions would tend to accumulate amino acid changes along the infection process, an effect that could be accelerated by antiviral treatments. In this study, we have analyzed the E1–E2 region of 23 HCV patients non-responders to antiviral treatment, 7 of which were infected with subtype 1a, 15 with subtype 1b, and 1 with a new HCV-1 subtype, before and after 6 and/or 12 mo…

Theoretical study of the temperature dependence of dynamic effects in thymidylate synthase.

2010

A theoretical study of the temperature dependence of dynamic effects in the rate limiting step of the reaction catalyzed by thymidylate synthase is presented in this paper. From hybrid Quantum Mechanics/Molecular Mechanics (QM/MM) optimizations of transition state structures within a fully flexible molecular model, free downhill molecular dynamics trajectories have been performed at four different temperatures. The analysis of the reactive and non-reactive trajectories in the enzyme environment has allowed us to study the geometric and electronic coupling between the substrate, the cofactor and the protein. The results show how the contribution of dynamic effects to the rate enhancement mea…

The Many Faces of a Translation

2000

First-order translations have recently been characterized as the maps computed by aperiodic single-valued nondeterministic finite transducers (NFTs). It is shown here that this characterization lifts to "V-translations" and "V-single-valued-NFTs", where V is an arbitrary monoid pseudovariety. More strikingly, 2-way V-machines are introduced, and the following three models are shown exactly equivalent to Eilenberg's classical notion of a bimachine when V is a group variety or when V is the variety of aperiodic monoids: V-translations, V-single-valued-NFTs and 2-way V-transducers.

Del terrorismo a la guerra

2004

Quantum Finite One-Counter Automata

1999

In this paper the notion of quantum finite one-counter automata (QF1CA) is introduced. Introduction of the notion is similar to that of the 2-way quantum finite state automata in [1]. The well-formedness conditions for the automata are specified ensuring unitarity of evolution. A special kind of QF1CA, called simple, that satisfies the well-formedness conditions is introduced. That allows specify rules for constructing such automata more naturally and simpler than in general case. Possible models of language recognition by QF1CA are considered. The recognition of some languages by QF1CA is shown and compared with recognition by probabilistic counterparts.