1,753 research outputs found

    Oral bacterial microbiota and traumatic injuries of free-ranging Phrynops geoffroanus (Testudines, Chelidae) in southeastern Brazil

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    During 2006 and 2007, we collected free-ranging Phrynops geoffroanus, from two anthropogenically altered rivers in southeastern Brazil. Oral microbiological samples were taken for isolation of aerobic and facultative anaerobic bacteria; a physical examination was performed;and we evaluated possible effects on the turtles’ health. Twenty-nine species of bacteria were isolated in Piracicaba River turtles (n=10), and twenty-four species in Piracicamirim stream turtles (n=8), most of them gram-negative. In both sites, potential pathogens for reptiles were: Escherichia coli, Klebsiella pneumoniae, Enterobacter agglomerans, Citrobacter freundii, and Bacillus sp. Although boatpropeller lesions were common on the carapace of the turtles, we have not found turtles with signs of clinical diseases. The oral bacterial microbiota of P. geoffroanus inhabiting the Piracicaba River basin are composed of a diverse microbe spectrum, and long-term studies of the effects of pollution and traumatic injuries on this population and its microbial flora are warranted

    Microbiota bacteriana oral e lesões traumáticas no cágado Phrynops geoffroanus (Testudines, Chelidae) no sudeste do Brasil

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    Entre 2006 e 2007, coletamos amostras microbiológicas da cavidade oral de cágados Phrynops geoffroanus de vida livre, em dois rios antropizados da região sudeste do Brasil, para o isolamento de bactérias aeróbicas e anaeróbicas facultativas, e realizamos um exame físico e avaliamos possíveis efeitos sobre o estado de saúde dos animais. Vinte e nove espécies de bactérias foram isoladas em cágados do rio Piracicaba (n=10), e vinte e quatro espécies em animais do ribeirão Piracicamirim (n=8), a maioria delas gram-negativas. Em ambos os sítios estudados foram isolados patógenos potenciais para répteis, como Escherichia coli, Klebsiella pneumoniae, Enterobacter agglomerans, Citrobacter freundii e Bacillus sp. Embora lesões na carapaça dos cágados, causadas por hélices de barcos, foram um achado comum no exame físico, não encontramos animais com sinais clínicos de doenças. A microbiota bacteriana oral dos cágados que habitam a bacia do rio Piracicaba é composta por um amplo espectro de bactérias, e estudos de longa duração sobre os efeitos da poluição e de lesões traumáticas nesta população e de sua microbiota oral são recomendados.During 2006 and 2007, we collected free-ranging Phrynops geoffroanus, from two anthropogenically altered rivers in southeastern Brazil. Oral microbiological samples were taken for isolation of aerobic and facultative anaerobic bacteria; a physical examination was performed; and we evaluated possible effects on the turtles' health. Twenty-nine species of bacteria were isolated in Piracicaba River turtles (n=10), and twenty-four species in Piracicamirim stream turtles (n=8), most of them gram-negative. In both sites, potential pathogens for reptiles were: Escherichia coli, Klebsiella pneumoniae, Enterobacter agglomerans, Citrobacter freundii, and Bacillus sp. Although boat propeller lesions were common on the carapace of the turtles, we have not found turtles with signs of clinical diseases. The oral bacterial microbiota of P. geoffroanus inhabiting the Piracicaba River basin are composed of a diverse microbe spectrum, and long-term studies of the effects of pollution and traumatic injuries on this population and its microbial flora are warranted

    Multiself-loop Lackadaisical Quantum Walk with Partial Phase Inversion

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    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 ll 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 mm self-loops, with weights l=l/ml' = l/m, where ll is a real parameter. The phase inversion is based on Grover's algorithm and acts partiality, modifying the phase of a given quantity sms \leqslant m of self-loops. On a hypercube structure, we analyzed the situation where s=1s=1 and 1m301 \leqslant m \leqslant 30 and investigated its effects in the search for 1 to 12 marked vertices. Based on two ideal weights ll 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

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    The Gr\"uneisen ratio Γ\Gamma, i.e., the singular part of the ratio of thermal expansion to the specific heat, has been broadly employed to explore both finite-TT and quantum critical points (QCPs). For a genuine quantum phase transition (QPT), thermal fluctuations are absent and thus the thermodynamic Γ\Gamma cannot be employed. We propose a quantum analogue to Γ\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

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

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    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 ll. 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 ll for such scenarios of arbitrary dimensions. It turns out the other fits of ll 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

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

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    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

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

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    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.

    Prognostic value of epidermal growth factor receptors in gastric cancer: a survival analysis by Weibull model incorporating long-term survivors

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    BACKGROUND: There is no consensus about the prognostic role of HER2 expression and that of other members of the EGFR family in gastric cancer patients. The aim of this study was to evaluate the prognostic value of the EGFR family in gastric cancer. METHODS: This retrospective study included 201 patients with gastric and esophagogastric junction adenocarcinoma stages 0–IV (AJCC 6th edition) who underwent primary tumor resection. Tissues from primary tumors were analyzed by tissue microarray technology and immunohistochemistry. Correlations between receptor expression and clinicopathological characteristics were performed according to the chi-square test. Survival analysis was calculated according to the Weibull model with a mixture model incorporating long-term survivors. Multivariate analysis of prognostic factors was performed by a regression model incorporating long-term survivors with the Weibull distribution. RESULTS: Membrane expression of HER1, HER2, and HER4 were 9, 17, and 15 %, respectively. No membrane expression of HER3 was observed. Cytoplasmic expression of HER1, HER3, and HER4 were 45, 62, and 24 %, respectively. HER2 and HER3 expression were correlated (p < 0.001) and associated with intestinal-type histology (p = 0.001 and p < 0.001, respectively) and advanced age (p = 0.011 and p = 0.008, respectively). According to a regression model adjusted for age, surgical radicality, surgical modality, Laurén histology, adjuvant therapy, TNM stage, and receptor expressions, only TNM stage showed prognostic influence. CONCLUSIONS: According to analysis by a parametric model, the EGFR family did not have prognostic influence in the gastric cancer population studied. The data presented showed a correlation between HER2 and HER3 expression, which might suggest a potential role for HER2–HER3 heterodimerization inhibitors
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