Quantum BRST operators in the extended BRST-anti-BRST formalism

The quantum BRST-anti-BRST operators are explicitely derived and the consequences related to correlation functions are investigated. The connection with the standard formalism and the loopwise expansions for quantum operators and anomalies in Sp(2) approach are analyzed.Comment: 7 page

Assessing the impact of participatory research in rice breeding on poor rice farming households with emphasis on women farmers: a case study in eastern Uttar Pradesh, India

For the past years since the Consultative Group of International Agricultural Research (CGIAR) Systemwide Initiative on Participatory Research and Gender Analysis (PRGA) was initiated, guides for impact assessment of PRGA have been developed (Lilja and Ashby 1999; Johnson et.al., 2000; Lilja and Johnson 2001). However, according to Farnworth and Jiggins (2003) while there is rapidly growing literature on the impacts of PPB on farmers, this is not further differentiated by sex. Despite the immense literature on the impacts of production, post production technologies on women farmers, systematic studies on the impacts of PPB on women in any category, either in terms of the effects of being a participant in a participatory plant breeding process (PPB) process, or in terms of the impact of the new materials generated is few. There is practically no literature that examines the effects of PPB – either as process or in terms of the impacts of the emergent materials – on gender relations at the household, community or any other relevant social or geographic scale along the food chain. Even with women’s active involvement in rice production, post harvest and seed management, scientists who are mostly male often talk with the male farmers only. Ignoring women’s knowledge and preference for rice varieties may be an obstacle to adoption of improved varieties, particularly in areas with gender-specific tasks, and in farm activities where women have considerable influence. Feldstein (1996) cited three different ways in which gender analysis can be considered in participatory research. These are: the efficiency argument, equity oriented, and empowerment. This study attempts to fill in these research gaps. The objectives of this paper are to: a) discuss the process used in integrating participatory research and gender analysis in breeding for drought prone and submergence prone environment; b) assess how gender analysis contributed to the design and implementation of the research and development outcomes; c) assess the impacts of PVS on poor women farmers, particularly on women’s empowerment; and d) recommend strategies to further enhance women’s roles in ensuring household food (rice) food security and improving their social status within the household and the community

Transmittivity measurements by means of squeezed vacuum light

A method for measuring the transmittivity of optical samples by using squeezed--vacuum radiation is illustrated. A squeezed vacuum field generated by a below--threshold optical parametric oscillator is propagated through a nondispersive medium and detected by a homodyne apparatus. The variance of the detected quadrature is used for measuring the transmittivity. With this method it is drastically reduced the number of photons passing through the sample during the measurement interval. The results of some tests are reported.Comment: 14 pages, 8 figure

A two-step optimized measurement for the phase-shift

A two-step detection strategy is suggested for the precise measurement of the optical phase-shift. In the first step an unsharp, however, unbiased joint measurement of the phase and photon number is performed by heterodyning the signal field. Information coming from this step is then used for suitable squeezing of the probe mode to obtain a sharp phase distribution. Application to squeezed states leads to a phase sensitivity scaling as $\Delta\phi\simeq N^{-1}$ relative to the total number of photons impinged into the apparatus. Numerical simulations of the whole detection strategy are also also presented

Purity of Gaussian states: measurement schemes and time-evolution in noisy channels

We present a systematic study of the purity for Gaussian states of single-mode continuous variable systems. We prove the connection of purity to observable quantities for these states, and show that the joint measurement of two conjugate quadratures is necessary and sufficient to determine the purity at any time. The statistical reliability and the range of applicability of the proposed measurement scheme is tested by means of Monte Carlo simulated experiments. We then consider the dynamics of purity in noisy channels. We derive an evolution equation for the purity of general Gaussian states both in thermal and squeezed thermal baths. We show that purity is maximized at any given time for an initial coherent state evolving in a thermal bath, or for an initial squeezed state evolving in a squeezed thermal bath whose asymptotic squeezing is orthogonal to that of the input state.Comment: 9 Pages, 6 Figures; minor errors correcte

Análise faunística de cochonilhas (hemiptera: sternorrhyncha) na cultura da videira no município de Pinto Bandeira, Rio Grande do Sul, Brasil.

O Rio Grande do Sul é o principal estado produtor de uvas e vinhos do país, com destaque para a região da Serra Gaúcha. Um dos principais problemas enfrentados pelos viticultores é a presença de cochonilhas que ocorrem na parte aérea da cultura e que, dependendo da severidade dos danos causam a morte da planta. Nesse trabalho foi realizada uma análise faunística das cochonilhas presentes na parte aérea de videiras, no município de Pinto Bandeira, RS. As amostragens foram realizadas quinzenalmente em vinhedo comercial de 1 ha de Vitis vinifera L. cultivar Merlot. Foram coletadas amostras de cochonilhas presentes no ritidoma e brotações, de janeiro de 2011 a janeiro de 2013. A triagem e identificação dos espécimes foram realizadas em laboratório com o auxílio de microscópio óptico e bibliografia especializada. Os dados obtidos foram analisados a partir da determinação da frequência, constância e dominância. Foram identificadas duas espécies de cochonilhas incluídas em Diaspididae - Hemiberlesia latanie e Pseudaonidia marquesi; e uma em Monophlebidae - Icerya schrottkyi. Hemiberlesia latanie foi a espécie que apresentou 89,72% de frequência, I. schrottkyi 7,13% e P. marquesi 3,14%. Hemiberlesia latanie foi a cochonilha dominante, mais frequente e constante no vinhedo

Minimum decoherence cat-like states in Gaussian noisy channels

We address the evolution of cat-like states in general Gaussian noisy channels, by considering superpositions of coherent and squeezed-coherent states coupled to an arbitrarily squeezed bath. The phase space dynamics is solved and decoherence is studied keeping track of the purity of the evolving state. The influence of the choice of the state and channel parameters on purity is discussed and optimal working regimes that minimize the decoherence rate are determined. In particular, we show that squeezing the bath to protect a non squeezed cat state against decoherence is equivalent to orthogonally squeezing the initial cat state while letting the bath be phase insensitive.Comment: 10 pages, 2 figures, references added, submitted to J. Opt.

Clustering Molecular Dynamics Trajectories for Optimizing Docking Experiments

Molecular dynamics simulations of protein receptors have become an attractive tool for rational drug discovery. However, the high computational cost of employing molecular dynamics trajectories in virtual screening of large repositories threats the feasibility of this task. Computational intelligence techniques have been applied in this context, with the ultimate goal of reducing the overall computational cost so the task can become feasible. Particularly, clustering algorithms have been widely used as a means to reduce the dimensionality of molecular dynamics trajectories. In this paper, we develop a novel methodology for clustering entire trajectories using structural features from the substrate-binding cavity of the receptor in order to optimize docking experiments on a cloud-based environment. The resulting partition was selected based on three clustering validity criteria, and it was further validated by analyzing the interactions between 20 ligands and a fully flexible receptor (FFR) model containing a 20 ns molecular dynamics simulation trajectory. Our proposed methodology shows that taking into account features of the substrate-binding cavity as input for the k-means algorithm is a promising technique for accurately selecting ensembles of representative structures tailored to a specific ligand

Quantifying decoherence in continuous variable systems

We present a detailed report on the decoherence of quantum states of continuous variable systems under the action of a quantum optical master equation resulting from the interaction with general Gaussian uncorrelated environments. The rate of decoherence is quantified by relating it to the decay rates of various, complementary measures of the quantum nature of a state, such as the purity, some nonclassicality indicators in phase space and, for two-mode states, entanglement measures and total correlations between the modes. Different sets of physically relevant initial configurations are considered, including one- and two-mode Gaussian states, number states, and coherent superpositions. Our analysis shows that, generally, the use of initially squeezed configurations does not help to preserve the coherence of Gaussian states, whereas it can be effective in protecting coherent superpositions of both number states and Gaussian wave packets.Comment: Review article; 36 pages, 19 figures; typos corrected, references adde