On Applying the Lackadaisical Quantum Walk Algorithm to Search for Multiple Solutions on Grids

Quantum computing holds the promise of improving the information processing power to levels unreachable by classical computation. Quantum walks are heading the development of quantum algorithms for searching information on graphs more efficiently than their classical counterparts. A quantum-walk-based algorithm that is standing out in the literature is the lackadaisical quantum walk. The lackadaisical quantum walk is an algorithm developed to search two-dimensional grids whose vertices have a self-loop of weight $l$. In this paper, we address several issues related to the application of the lackadaisical quantum walk to successfully search for multiple solutions on grids. Firstly, we show that only one of the two stopping conditions found in the literature is suitable for simulations. We also demonstrate that the final success probability depends on the space density of solutions and the relative distance between solutions. Furthermore, this work generalizes the lackadaisical quantum walk to search for multiple solutions on grids of arbitrary dimensions. In addition, we propose an optimal adjustment of the self-loop weight $l$ for such scenarios of arbitrary dimensions. It turns out the other fits of $l$ found in the literature are particular cases. Finally, we observe a two-to-one relation between the steps of the lackadaisical quantum walk and the ones of Grover's algorithm, which requires modifications in the stopping condition. In conclusion, this work deals with practical issues one should consider when applying the lackadaisical quantum walk, besides expanding the technique to a wider range of search problems.Comment: Extended version of the conference paper available at https://doi.org/10.1007/978-3-030-61377-8_9 . 21 pages, 6 figure

Multiself-loop Lackadaisical Quantum Walk with Partial Phase Inversion

Quantum walks are the quantum counterpart of classical random walks and provide an intuitive framework for building new quantum algorithms. The lackadaisical quantum walk, which is a quantum analog of the lazy random walk, is obtained by adding a self-loop transition to each state allowing the walker to stay stuck in the same state, being able to improve the performance of the quantum walks as search algorithms. However, the high dependence of a weight $l$ makes it a key parameter to reach the maximum probability of success in the search process. Although many advances have been achieved with search algorithms based on quantum walks, the number of self-loops can also be critical for search tasks. Believing that the multiple self-loops have not yet been properly explored, this article proposes the quantum search algorithm Multiself-loop Lackadaisical Quantum Walk with Partial Phase Inversion, which is based on a lackadaisical quantum walk with multiple self-loops where the target state phase is partially inverted. Each vertex has $m$ self-loops, with weights $l' = l/m$, where $l$ is a real parameter. The phase inversion is based on Grover's algorithm and acts partiality, modifying the phase of a given quantity $s \leqslant m$ of self-loops. On a hypercube structure, we analyzed the situation where $s=1$ and $1 \leqslant m \leqslant 30$ and investigated its effects in the search for 1 to 12 marked vertices. Based on two ideal weights $l$ used in the literature, we propose two new weight values. As a result, with the proposal of the Multiself-loop Lackadaisical Quantum Walk with partial phase inversion of target states and the new weight values for the self-loop, this proposal improved the maximum success probabilities to values close to 1. This article contributes with a new perspective on the use of quantum interferences in the construction of new quantum search algorithms.Comment: 16 pages, 4 figures, 3 table

Gr\"uneisen parameter as an entanglement compass

The Gr\"uneisen ratio $\Gamma$, i.e., the singular part of the ratio of thermal expansion to the specific heat, has been broadly employed to explore both finite-$T$ and quantum critical points (QCPs). For a genuine quantum phase transition (QPT), thermal fluctuations are absent and thus the thermodynamic $\Gamma$ cannot be employed. We propose a quantum analogue to $\Gamma$ that computes entanglement as a function of a tuning parameter and show that QPTs take place only for quadratic non-diagonal Hamiltonians. We showcase our approach using the quantum 1D Ising model with transverse field and Kane's quantum computer. The slowing down of the dynamics and thus the ``creation of mass'' close to any QCP/QPT is also discussed.Comment: 5 pages, 3 figures, comments are wellcome

Efficacy of carfentrazone-ethyl and glyphosate mixtures on control of Commelina benghalensis in coffee crop (Coffea arabica)

O objetivo do presente trabalho foi avaliar a eficácia do herbicida carfentrazone-ethyl em mistura com glyphosate no controle de trapoeraba (Commelina henghafensis) na cultura do café (CojJea arabica). O experimento foi conduzido na Fazenda São José, localizada no município de Garça, SP. Os tratamentos utilizados foram: carfentrazone + glyphosate (10+2500, 15+1200, 20+ 1200, 25+ 1200, 30+ 1200, 40+ 1200 e 50+ 1200 g/ha), 2,4-0 (2680 g/ha), glyphosate (1200 g/ha) e uma testemunha sem controle. Foi utilizado o delineamento experimental em blocos ao acaso com 3 repetições. A combinação de carfentrazone-ethyl com glyphosate foi eficiente no controle de trapoeraba a partir da dose de 75 g/ha. A máxima dose utilizada de carfentrazone-ethyl (125 g/ha) na combinação com glyphosate, provocou total controle de trapoeraba aos 7 dias após os tratamentos. O glyphosate foi mais eficaz no controle das plantas daninhas e provocou dessecação mais rápida. quando foram utilizadas doses crescentes de carfentrazone acima de 25 g/ha (meia dose) comparado com o herbicida glyphosate aplicado isoladamente. Todos os herbicidas testados não apresentaram toxicidade nas folhas de café. The objective of this research was to evaluate the efficacy in control of Commefina benghalensis using mixtures of carfentrazone-ethyl and glyphosate herbicides on the coffee crop. The experiment was carried out in São José Farm, Garça- SP, Brazil. The treatrnents were: postemergence application of carfentrazone-ethyl + glyphosate (10+ 1200, 15+ 1200,20+ 1200, 25+1200,30+1200,40+1200 and 50+1200 g/ha), 2,4-0 (2680 g/ha), glyphosate (1200 g/ha) and an untreated control. Experimental design was a randomized complete block with three replications. The carfentrazone-ethyl mixture with glyphosate herbicide was efficient in the control of Commelina benghalensis starting with doses greater than or equal to 30 g/ha. The maximum dose of carfentrazone-ethyl (50 g/ha) mixture and glyphosate herbicides were fully efficient in control of the weed, up to 15 days after application on the coffee crop. The glyphosate herbicide control on the weed species was more efficient, presenting a faster dessication period, when used with increasing doses of carfentrazone herbicide above 25 g/ha, when compared with glyphosate alone. The evaluated herbicides and mixtures did not present toxicity to the coffee leaves.

Acute exercise induce endothelial nitric oxide synthase phosphorylation via Akt and AMP-activated protein kinase in aorta of rats: Role of reactive oxygen species

AbstractBackgroundAcute exercise increases reactive oxygen species (ROS) levels, including hydrogen peroxide (H2O2). H2O2 promotes endothelial nitric oxide synthase (eNOS) activation and phosphorylation in endothelial cells. With this in mind, the present study was designed to evaluate ex vivo eNOS phosphorylation in rat aortas incubated with H2O2 and to test this hypothesis in vivo in the aortas of rats submitted to acute exercise.MethodsFor ex vivo studies, six groups of aortic tissue were formed: control, H2O2, N-acetylcysteine (NAC), LY294002, compound C, and LY294002 plus compound C. While incubation with H2O2 increased Akt, AMPK and eNOS phosphorylation, pre-incubation with NAC strongly reduced the phosphorylation of these enzymes. For in vivo studies, male Wistar rats were divided into four groups: control, cont+NAC, exercise, and exer+NAC. After a 3h swimming session, animals were decapitated and aortas were excised for biochemical and immunoblotting analysis.ResultsAcute exercise increased superoxide levels and dichlorofluorescein (DCF) concentrations, and this increase was related to phosphorylation of Akt, AMPK and eNOS. On the other hand, use of NAC reduced superoxide levels and DCF concentration. Reduced superoxide levels and DCF in the exer+NAC group were associated with decreased Akt, AMPK and eNOS phosphorylation. These results appear to be connected with vascular function because VASP phosphorylation increased in acute exercise and decreased in exer+NAC.ConclusionOur results indicate that ROS induced by acute exercise play the important role of activating eNOS, a process apparently mediated by Akt and AMPK

Análise Funcional de Comportamentos Verbais Inapropriados de um Esquizofrênico

The present study registered the inappropriate verbalizations of a schizophrenic male adult. The inappropriate verbal behaviors were observed during periods of brief exposure to four conditions: attention, non-contingent attention, demand and alone. Results indicated that these conditions affected the inadequate verbalizations in different ways. These results are discussed in terms of their implications for functional evaluations before the psychological interventions.  O presente estudo registrou as verbalizações inapropriadas de um esquizofrênico adulto e do sexo masculino. Os comportamentos verbais inapropriados foram observados durante breves períodos de exposição a quatro condições: atenção, atenção não contingente, demanda e sozinho. Os resultados indicaram que as condições afetaram os comportamentos verbais inapropriados diferentemente. Esses resultados são discutidos em termos das suas implicações para as avaliações funcionais antes de intervenções psicológicas. &nbsp

PARSEC PARAMETERIZATION METHODOLOGY FOR ENHANCING AIRFOILS GEOMETRY USING PSO ALGORITHM

The electromechanical generating system is mainly based on the characteristics wherein the turbine has to ”harvest” the energy of a working fluid. Thus, the engineering behind the blades, such as the geometry and construction, must be effectively consolidated to increase the overall turbine efficiency. This work aims to go further into the computational principles of modeling the turbine blades, precisely, the hydrokinetic turbine hydrofoil built by LEA (Engineering Laboratory and Environment - UNB). The study has a focus on designing and analyzing, through numerical studies of parameterization and optimization profiles, blades using computational tools such as MATLAB R2016b and XFOIL. In this case, the model study is part of the airfoil theory combined with the Particle Swarm Optimization technic (PSO), which are implemented to get a maximum utilization of the aerodynamic coefficient CL over CD of the blade. Furthermore, an optimal turbine blade geometry, set by PARSEC parameter, is found and compared with results obtained from the original hydrofoil, using the software of profile analysis XFOIL, to certify the mathematical method, proving its effectiveness to parameterize hydrodynamic profiles and optimize their geometries.Keywords: Hydrokinetic Turbine. Airfoils. Parameterization and Optimization. Parsec. PSO