753 research outputs found
On q-Deformed Supersymmetric Classical Mechanical Models
Based on the idea of quantum groups and paragrassmann variables, we presenta
generalization of supersymmetric classical mechanics with a deformation
parameter dealing with the case. The
coordinates of the -superspace are a commuting parameter and a
paragrassmann variable , where . The generator and
covariant derivative are obtained, as well as the action for some possible
superfields.Comment: No figures, 14 pages, Latex, revised versio
pompeii
O corpo é um pedaço da carne do mundo. O mundo é a pele do corpo
Simple implementation of complex functionals: scaled selfconsistency
We explore and compare three approximate schemes allowing simple
implementation of complex density functionals by making use of selfconsistent
implementation of simpler functionals: (i) post-LDA evaluation of complex
functionals at the LDA densities (or those of other simple functionals); (ii)
application of a global scaling factor to the potential of the simple
functional; and (iii) application of a local scaling factor to that potential.
Option (i) is a common choice in density-functional calculations. Option (ii)
was recently proposed by Cafiero and Gonzalez. We here put their proposal on a
more rigorous basis, by deriving it, and explaining why it works, directly from
the theorems of density-functional theory. Option (iii) is proposed here for
the first time. We provide detailed comparisons of the three approaches among
each other and with fully selfconsistent implementations for Hartree,
local-density, generalized-gradient, self-interaction corrected, and
meta-generalized-gradient approximations, for atoms, ions, quantum wells and
model Hamiltonians. Scaled approaches turn out to be, on average, better than
post-approaches, and unlike these also provide corrections to eigenvalues and
orbitals. Scaled selfconsistency thus opens the possibility of efficient and
reliable implementation of density functionals of hitherto unprecedented
complexity.Comment: 12 pages, 1 figur
Universal Quantum Walk Control Plane for Quantum Networks
Quantum networks are complex systems formed by the interaction among quantum
processors through quantum channels. Analogous to classical computer networks,
quantum networks allow for the distribution of quantum operations among quantum
processors. In this work, we describe a Quantum Walk Control Protocol (QWCP) to
perform distributed quantum operations in a quantum network. We consider a
generalization of the discrete-time coined quantum walk model that accounts for
the interaction between quantum walks in the network graph with quantum
registers inside the network nodes. QWCP allows for the implementation of
networked quantum services, such as distributed quantum computing and
entanglement distribution, abstracting hardware implementation and the
transmission of quantum information through channels. Multiple interacting
quantum walks can be used to propagate entangled control signals across the
network in parallel. We demonstrate how to use QWCP to perform distributed
multi-qubit controlled gates, which shows the universality of the protocol for
distributed quantum computing. Furthermore, we apply the QWCP to the task of
entanglement distribution in a quantum network.Comment: 27 pages; 2 figures. A preliminary version of this work was presented
at IEEE International Conference on Quantum Computing and Engineering 2021
(QCE21). arXiv admin note: text overlap with arXiv:2106.0983
Sorting of mitochondrial and plastid heteroplasmy in Arabidopsis is extremely rapid and depends on MSH1 activity
The fate of new mitochondrial and plastid mutations depends on their ability to persist and spread among the numerous organellar genome copies within a cell (heteroplasmy). The extent to which heteroplasmies are transmitted across generations or eliminated through genetic bottlenecks is not well understood in plants, in part because their low mutation rates make these variants so infrequent. Disruption of MutS Homolog 1 (MSH1), a gene involved in plant organellar DNA repair, results in numerous de novo point mutations, which we used to quantitatively track the inheritance of single nucleotide variants in mitochondrial and plastid genomes in Arabidopsis. We found that heteroplasmic sorting (the fixation or loss of a variant) was rapid for both organelles, greatly exceeding rates observed in animals. In msh1 mutants, plastid variants sorted faster than those in mitochondria and were typically fixed or lost within a single generation. Effective transmission bottleneck sizes (N) for plastids and mitochondria were N ⌠1 and 4, respectively. Restoring MSH1 function further increased the rate of heteroplasmic sorting in mitochondria (N ⌠1.3), potentially because of its hypothesized role in promoting gene conversion as a mechanism of DNA repair, which is expected to homogenize genome copies within a cell. Heteroplasmic sorting also favored GC base pairs. Therefore, recombinational repair and gene conversion in plant organellar genomes can potentially accelerate the elimination of heteroplasmies and bias the outcome of this sorting process.publishedVersio
Integrated optical fiber force myography sensor as pervasive predictor of hand postures
Force myography (FMG) is an appealing alternative to traditional electromyography in biomedical applications, mainly due to its simpler signal pattern and immunity to electrical interference. Most FMG sensors, however, send data to a computer for further processing, which reduces the user mobility and, thus, the chances for practical application. In this sense, this work proposes to remodel a typical optical fiber FMG sensor with smaller portable components. Moreover, all data acquisition and processing routines were migrated to a Raspberry Pi 3 Model B microprocessor, ensuring the comfort of use and portability. The sensor was successfully demonstrated for 2 input channels and 9 postures classification with an average precision and accuracy of ~99.5% and ~99.8%, respectively, using a feedforward artificial neural network of 2 hidden layers and a competitive output layer11CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTĂFICO E TECNOLĂGICO - CNPQCOORDENAĂĂO DE APERFEIĂOAMENTO DE PESSOAL DE NĂVEL SUPERIOR - CAPESFUNDAĂĂO DE AMPARO Ă PESQUISA DO ESTADO DE SĂO PAULO - FAPESPNĂŁo tem0012017/25666-
Spin 3/2 Pentaquarks
We investigate the possible existence of the spin 3/2 pentaquark states using
interpolating currents with K-N color-octet structure in the framework of QCD
finite energy sum rule (FESR). We pay special attention to the convergence of
the operator product expansion
Asymmetric exclusion model with several kinds of impurities
We formulate a new integrable asymmetric exclusion process with
kinds of impurities and with hierarchically ordered dynamics.
The model we proposed displays the full spectrum of the simple asymmetric
exclusion model plus new levels. The first excited state belongs to these new
levels and displays unusual scaling exponents. We conjecture that, while the
simple asymmetric exclusion process without impurities belongs to the KPZ
universality class with dynamical exponent 3/2, our model has a scaling
exponent . In order to check the conjecture, we solve numerically the
Bethe equation with N=3 and N=4 for the totally asymmetric diffusion and found
the dynamical exponents 7/2 and 9/2 in these cases.Comment: to appear in JSTA
Utilization of organic soil amendments and phosphorus fertilizer to improve chemical properties of degraded dry land Vertisol and maize yield
This study aimed to evaluate the effects of soil amendment and phosphorus fertilizer application techniques on the chemical properties of dry land Vertisols, P absorption efficiency by maize and maize yield. The study was conducted on farmer's land located in Noelbaki Village, Central Kupang District, Kupang Regency, East Nusa Tenggara, Indonesia. The study was conducted during two planting seasons, namely the rainy season 2020/2021 (PS-1) and the dry season 2021 (PS-2). The soil used in this experiment was included in the degraded Vertisols. This study used a split-plot design with three replications. The main plot was the type of organic soil-amendment material, and the subplot was the technique (dose and stage) of applying phosphorus fertilizer sourced from SP-36. The results showed that organic soil amendment and phosphorus fertilizer application techniques could improve soil chemical properties, P uptake, P absorption efficiency and maize yield in Vertisols until the second planting season. In the long term, the combination of maize stover biochar and the technique of applying phosphorus fertilizer (P3-T2) significantly increased the P uptake by 32.31 kg ha-1 (PS-1) and 31.23 kg ha-1 (PS-2), the P absorption efficiency by 28.65% (PS-1) and 27.75% (PS-2). The P3-T2 treatment gave maize yields of 6.92 t ha-1 (PS-1) and 6.92 t ha-1 (PS-2), which were higher than those of other treatments
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