2,992 research outputs found
Notes on two-parameter quantum groups, (II)
This paper is the sequel to [HP1] to study the deformed structures and
representations of two-parameter quantum groups
associated to the finite dimensional simple Lie algebras \mg. An equivalence
of the braided tensor categories \O^{r,s} and \O^{q} is explicitly
established.Comment: 21 page
The 2-Dimensional Quantum Euclidean Algebra
The algebra dual to Woronowicz's deformation of the 2-\-di\-men\-sion\-al
Euclidean group is constructed. The same algebra is obtained from
via contraction on both the group and algebra levels.Comment: 8 pages, LBL-31711 and UCB-PTH-92/0
Representations of the quantum matrix algebra
It is shown that the finite dimensional irreducible representaions of the
quantum matrix algebra ( the coordinate ring of ) exist only when both q and p are roots of unity. In this case th e space of
states has either the topology of a torus or a cylinder which may be thought of
as generalizations of cyclic representations.Comment: 20 page
Multi-heme Cytochromes in Shewanella oneidensis MR-1:Structures, functions and opportunities
Multi-heme cytochromes are employed by a range of microorganisms to transport electrons over distances of up to tens of nanometers. Perhaps the most spectacular utilization of these proteins is in the reduction of extracellular solid substrates, including electrodes and insoluble mineral oxides of Fe(III) and Mn(III/IV), by species of Shewanella and Geobacter. However, multi-heme cytochromes are found in numerous and phylogenetically diverse prokaryotes where they participate in electron transfer and redox catalysis that contributes to biogeochemical cycling of N, S and Fe on the global scale. These properties of multi-heme cytochromes have attracted much interest and contributed to advances in bioenergy applications and bioremediation of contaminated soils. Looking forward there are opportunities to engage multi-heme cytochromes for biological photovoltaic cells, microbial electrosynthesis and developing bespoke molecular devices. As a consequence it is timely to review our present understanding of these proteins and we do this here with a focus on the multitude of functionally diverse multi-heme cytochromes in Shewanella oneidensis MR-1. We draw on findings from experimental and computational approaches which ideally complement each other in the study of these systems: computational methods can interpret experimentally determined properties in terms of molecular structure to cast light on the relation between structure and function. We show how this synergy has contributed to our understanding of multi-heme cytochromes and can be expected to continue to do so for greater insight into natural processes and their informed exploitation in biotechnologies
Two-parameter quantum general linear supergroups
The universal R-matrix of two-parameter quantum general linear supergroups is
computed explicitly based on the RTT realization of
Faddeev--Reshetikhin--Takhtajan.Comment: v1: 14 pages. v2: published version, 9 pages, title changed and the
section on central extension remove
Multibody parameter estimation: A comprehensive case-study for an innovative rear suspension
Numerical and virtual simulation of mechanical systems is a standard part of product development in the automotive sector, and multibody techniques are a consolidated tool to describe vehicle dynamics, elasto- kinematic behavior, handling, and comfort. To achieve high precision results as output of simulations, it is essential to provide the system with reliable data as input, and to accurately describe the vehicle and its subsystems. The task of gathering objective parameters to fully describe a vehicle can seem trivial to the stakeholders directly connected to a project, that can access detailed design data and a plethora of schemes and datasheets covering all subsystems of a vehicle. However, whenever this task regards benchmarking, prototyping, research projects or niche/low-volume products, data availability decreases drastically, and alternative forms of data acquisition become essential. This paper proposes a comprehensive overview of data gathering and experimental procedures used to reliably extract parameters of an existing vehicle using quick and accessible strategies. The analysis is based on a case-study project of an A-segment vehicle mounted with an innovative rear suspension scheme, whose behavior should be described by a dedicated elasto- kinematic multibody model as well as a full vehicle model for dynamic validation. The multibody model is based on Adams/Car with the inclusion of flexible elements, which is briefly described, while a closer focus is given to the experimental extraction of key features, such as: total mass, longitudinal and lateral position of the center of gravity, CoG height, wheel travel and wheel rate, shock-absorber damping coefficient, steering ratio, components inertia and flexible elements strain. The results obtained in the static and dynamic experimental validation suggest a good outcome from the methodology, that can be replicated on many kinds of vehicle modelling activities as an approachable and affordable experimental methodology for small projects
On the fluctuations of jamming coverage upon random sequential adsorption on homogeneous and heterogeneous media
The fluctuations of the jamming coverage upon Random Sequential Adsorption
(RSA) are studied using both analytical and numerical techniques. Our main
result shows that these fluctuations (characterized by )
decay with the lattice size according to the power-law . The exponent depends on the dimensionality of
the substrate and the fractal dimension of the set where the RSA process
actually takes place () according to .This
theoretical result is confirmed by means of extensive numerical simulations
applied to the RSA of dimers on homogeneous and stochastic fractal substrates.
Furthermore, our predictions are in excellent agreement with different previous
numerical results.
It is also shown that, studying correlated stochastic processes, one can
define various fluctuating quantities designed to capture either the underlying
physics of individual processes or that of the whole system. So, subtle
differences in the definitions may lead to dramatically different physical
interpretations of the results. Here, this statement is demonstrated for the
case of RSA of dimers on binary alloys.Comment: 20 pages, 8 figure
Mixing Bandt-Pompe and Lempel-Ziv approaches: another way to analyze the complexity of continuous-states sequences
In this paper, we propose to mix the approach underlying Bandt-Pompe
permutation entropy with Lempel-Ziv complexity, to design what we call
Lempel-Ziv permutation complexity. The principle consists of two steps: (i)
transformation of a continuous-state series that is intrinsically multivariate
or arises from embedding into a sequence of permutation vectors, where the
components are the positions of the components of the initial vector when
re-arranged; (ii) performing the Lempel-Ziv complexity for this series of
`symbols', as part of a discrete finite-size alphabet. On the one hand, the
permutation entropy of Bandt-Pompe aims at the study of the entropy of such a
sequence; i.e., the entropy of patterns in a sequence (e.g., local increases or
decreases). On the other hand, the Lempel-Ziv complexity of a discrete-state
sequence aims at the study of the temporal organization of the symbols (i.e.,
the rate of compressibility of the sequence). Thus, the Lempel-Ziv permutation
complexity aims to take advantage of both of these methods. The potential from
such a combined approach - of a permutation procedure and a complexity analysis
- is evaluated through the illustration of some simulated data and some real
data. In both cases, we compare the individual approaches and the combined
approach.Comment: 30 pages, 4 figure
Enhanced degradation of softwood versus hardwood by the white-rot fungus Pycnoporus coccineus
16 p.-8 fig.-1 tab. Courier, Marie et al.This study was also funded by the French National Research Agency (A*MIDEX project ANR11-IDEX-0001-02;ANR FUNLOCK ANR-13-BIME-0002-01). The work by the US Department of Energy Joint Genome Institute, a DOE Office of Science User
Facility, is supported by the Office of Science of the US Department of Energy under Contract No. DE-AC02-05CH11231.Peer reviewe
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