453 research outputs found
Neural Networks Architecture Evaluation in a Quantum Computer
In this work, we propose a quantum algorithm to evaluate neural networks
architectures named Quantum Neural Network Architecture Evaluation (QNNAE). The
proposed algorithm is based on a quantum associative memory and the learning
algorithm for artificial neural networks. Unlike conventional algorithms for
evaluating neural network architectures, QNNAE does not depend on
initialization of weights. The proposed algorithm has a binary output and
results in 0 with probability proportional to the performance of the network.
And its computational cost is equal to the computational cost to train a neural
network
Lorentz-violating effects in the Bose-Einstein condensation of an ideal bosonic gas
We have studied the effects of Lorentz-violation in the Bose-Einstein
condensation (BEC) of an ideal boson gas, by assessing both the nonrelativistic
and ultrarelativistic limits. Our model describes a massive complex scalar
field coupled to a CPT-even and Lorentz-violating background. We irst analyze
the nonrelativistic case, at this level by using experimental data, we obtain
upper-bounds for some LIV parameters. In the sequel, we have constructed the
partition function for the relativistic ideal boson gas which to be able of a
consistent description requires the imposition of severe restrictions on some
LIV coefficients. In both cases, we have demonstrated that the LIV
contributions are contained in an overall factor, which multiplies almost all
thermodynamical properties. An exception is the fraction of the condensed
particles.Comment: 7 pages Latex2e. To be published in Modern Physics Letters
Cebus cf. apella exhibits rapid acquisition of complex stimulus relations and emergent performance by exclusion
A “second generation” matching-to-sample procedure that minimizes past sources of artifacts involves (1) successive discrimination between sample stimuli, (2) stimulus displays ranging from four to 16 comparisons, (3) variable stimulus locations to avoid unwanted stimulus-location control, and (4) high accuracy levels (e.g., 90% correct on a 16-choice task in which chance accuracy is 6%). Examples of behavioral engineering with experienced capuchin monkeys included four-choice matching problems with video images of monkeys with substantially above-chance matching in a single session and 90% matching within six sessions. Exclusion performance was demonstrated by interspersing non-identical sample-comparison pairs within a baseline of a nine-comparison identity-matching-to-sample procedure with pictures as stimuli. The test for exclusion presented the newly “mapped” stimulus in a situation in which exclusion was not possible. Degradation of matching between physically non-identical forms occurred while baseline identity accuracy was sustained at high levels, thus confirming that Cebus cf. apella is capable of exclusion. Additionally, exclusion performance when baseline matching relations involved non-identical stimuli was shown
Microsatellites for the Amazonian Fish Hypophthalmus marginatus
We isolated 41 and characterized 17 microsatellite loci for evaluating the genetic structure of the Amazonian fish Hypophthalmus marginatus, from the Tocantins and Araguaia River in the Eastern Amazonia. Of the 17 selected microsatellite sequences, 15 were dinucleotide repeats, 9 of which were perfect (5–31 repetitions) and 6 were composite motifs. Among these 17 microsatellites, only two were polymorphic. The average number of alleles (Na) observed in the five examined populations ranged from 3.5 to 4.5, while the average observed heterozygosity (Ho) ranged from 0.3 to 0.6. The allelic frequency was less homogeneous at the locus Hm 5 than that for the Hm 13. Genetic diversity was measured in three upstream and two downstream populations under the influence of the Tucuruí Hydroelectric Dam. Our findings provide evidence for low levels of genetic diversity in H. marginatus of the Tocantis basin possibility related to the Dam construction. The Fst and Rst analysis fits well with migratory characteristics of H. marginatus, suggesting the existence of a gene flow mainly in the upstream or downstream directions. To test the hypothesis that the Dam was responsible for the detected reduction on this species genetic diversity, a large number of genetic markers are recommended, covering geographic distribution range of the fish species
Optimal Decision Making in Electrical Systems Using an Asset Risk Management Framework
In this paper, a methodology for optimal decision making for electrical systems is addressed. This methodology seeks to identify and to prioritize the replacement and maintenance of a power asset fleet optimizing the return of investment. It fulfills this objective by considering the risk index, the replacement and maintenance costs, and the company revenue. The risk index is estimated and predicted for each asset using both its condition records and by evaluating the consequence of its failure. The condition is quantified as the probability of failure of the asset, and the consequence is determined by the impact of the asset failure on the whole system. Failure probability is estimated using the health index as scoring of asset condition. The consequence is evaluated considering a failure impact on the objectives of reliability (energy not supplied -ENS), environment, legality, and finance using Monte Carlo simulations for an assumed period of planning. Finally, the methodology was implemented in an open-source library called PywerAPM for assessing optimal decisions, where the proposed mathematical optimization problem is solved. As a benchmark, the power transformer fleet of the New England IEEE 39 Bus System was used. Condition records were provided by a local utility to compute the health index of each transformer. Subsequently, a Monte Carlo contingency simulation was performed to estimate the energy not supplied for a period of analysis of 10 years. As a result, the fleet is ranked according to risk index, and the optimal replacement and maintenance are estimated for the entire fleet
The ecology of plant chemistry and multi-species interactions in diversified agroecosystems
COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPESCONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESPOver the past few years, our knowledge of how ecological interactions shape the structure and dynamics of natural communities has rapidly advanced. Plant chemical traits play key roles in these processes because they mediate a diverse range of direct and917COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPESCONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESPCOORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPESCONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESPsem informação2014/50316-7sem informaçãoWe thank the editors of this Research Topic, in particular Massuo Jorge Kato and Lydia Fumiko Yamaguchi, for the invitation to contribute. We also thank the two reviewers and the editor TM for the valuable contributions in the revision process of the man
Magnetic response dependence of ZnO based thin films on Ag doping and processing architecture
Multifunctional and multiresponsive thin films are playing an increasing role in modern technology. This work reports a study on the magnetic properties of ZnO and Ag-doped ZnO semiconducting films prepared with a zigzag-like columnar architecture and their correlation with the processing conditions. The films were grown through Glancing Angle Deposition (GLAD) co-sputtering technique to improve the induced ferromagnetism at room temperature. Structural and morphological characterizations have been performed and correlated with the paramagnetic resonance measurements, which demonstrate the existence of vacancies in both as-cast and annealed films. The magnetic measurements reveal changes in the magnetic order of both ZnO and Ag-doped ZnO films with increasing temperature, showing an evolution from a paramagnetic (at low temperature) to a diamagnetic behavior (at room temperature). Further, the room temperature magnetic properties indicate a ferromagnetic order even for the un-doped ZnO film. The results open new perspectives for the development of multifunctional ZnO semiconductors, the GLAD co-sputtering technique enables the control of the magnetic response, even in the un-doped semiconductor materials.The Brazilian agencies CNPq, CAPES partially supports the research. From Portugal side,
this work was supported by the Portuguese Foundation for Science and Technology (FCT) in the framework of the
Strategic Funding UID/FIS/04650/2020 and the junior research contract (A.F.). Financial support from the Basque
Government Industry Department under the ELKARTEK. HAZITEK and PIBA programs is also acknowledged
Efeitos dos exercícios pilates na função do tronco e na dor de pacientes com lombalgia / Effects of pilates exercices on trunk function and pain in patients with low back pain
Introdução: Evidências científi cas atuais apontam que a falta de resistência da musculatura lombar é o principal fator para desenvolvimento das dores lombares. O exercício físico em geral tem se mostrado benéfi co para recuperação da funcionalidade bem como para melhora dos sintomas clínicos dos pacientes com lombalgia crônica.
Objetivo: Avaliar os efeitos de um treinamento físico por meio dos exercícios de Pilates de solo nas variáveis de dor, flexibilidade, equilíbrio, força e resistência dos músculos lombares em pacientes com lombalgia de origem desconhecida.
Método: Foram avaliados 12 pacientes com lombalgia crônica (idade média de 33 anos), que realizaram um período de treinamento com o método tradicional de 13 exercícios Pilates (básico e intermediário no mat), duas vezes na semana, com duração de uma hora, durante um total de 11 semanas. As principais medidas de resultados analisadas pré- e pós-treinamento Pilates foram: (1) flexibilidade (Banco de Wells), (2) equilíbrio unipodal (plataforma de força), (3) força lombar (dinamometria), (4) resistência lombar (teste de Sorensen), e dor (Escala Visual Analógica: EVA).
Resultados: A amostra fi nal do estudo foi de quatro voluntários devido à perda experimental. Os resultados mostraram uma diminuição significativa da dor (P < 0.05), mas nenhuma diferença significativa entre pré- e pós-treinamento Pilates para as demais variáveis, apesar da leve melhora na fl exibilidade e força.
Conclusão: Os resultados do presente estudo apresentaram efeitos benéfi cos do treinamento Pilates para diminuir os sintomas de dor. Entretanto, novos estudos com maior número amostral devem ser realizados para melhor estabelecer os protocolos de exercícios Pilates em pacientes com lombalgia crônica.
Introduction: Scientific evidences report that poor back muscle endurance is the most risk factor for developing low back pain. Overall, physical exercise has been effective to recovery of the functioning as well as to improve the clinical symptoms of patients with low back pain.
Objective: To assess the effects of Pilates training on mat in variables of flexibility, balance, strength and endurance of the lumbar extensor muscles in patients with low back pain unknown.
Method: 16 patients with chronic low back pain (mean age 33 yrs) performed a training program with a mat method of 13 Pilates exercises (basic and intermediate), 2 x a week for a session of approximately 1h, during 11 weeks. The main outcome measures analyzed before (pre-) and post-Pilates training were: fl exibility (sit-and-reach during a Wells test), unipodal support (under a force platform),
strength (lumbar dynamometer) and endurance (Sorensen test) of lumbar muscles and pain (VAS).
Results: Significant decrease of the pain was found (P < 0.05). However, no significant changes were found for other variables analyzing in pre- and post-training, although the slight improvement in the flexibility and strength.
Conclusions: The results of the present study showed the effi cacy of the Pilates exercises to decrease pain. However, more studies would be conducted using much more subjects to establish better standardization of Pilates exercises in patients with low back pain
Increasing biomass in Amazonian forest plots
A previous study by Phillips et al. of changes in the biomass of permanent sample plots in Amazonian forests was used to infer the presence of a regional carbon sink. However, these results generated a vigorous debate about sampling and methodological issues. Therefore we present a new analysis of biomass change in old-growth Amazonian forest plots using updated inventory data. We find that across 59 sites, the above-ground dry biomass in trees that are more than 10 cm in diameter (AGB) has increased since plot establishment by 1.22 ± 0.43 Mg per hectare per year (ha-1 yr-1), where 1 ha = 104 m2), or 0.98 ± 0.38 Mg ha-1 yr-1 if individual plot values are weighted by the number of hectare years of monitoring. This significant increase is neither confounded by spatial or temporal variation in wood specific gravity, nor dependent on the allometric equation used to estimate AGB. The conclusion is also robust to uncertainty about diameter measurements for problematic trees: for 34 plots in western Amazon forests a significant increase in AGB is found even with a conservative assumption of zero growth for all trees where diameter measurements were made using optical methods and/or growth rates needed to be estimated following fieldwork. Overall, our results suggest a slightly greater rate of net stand-level change than was reported by Phillips et al. Considering the spatial and temporal scale of sampling and associated studies showing increases in forest growth and stem turnover, the results presented here suggest that the total biomass of these plots has on average increased and that there has been a regional-scale carbon sink in old-growth Amazonian forests during the previous two decades
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