Dissipation instability of Couette-like adiabatic flows in a plane channel

The mixed convection flow in a plane channel with adiabatic boundaries is examined. The boundaries have an externally prescribed relative velocity defining a Couette-like setup for the flow. A stationary flow regime is maintained with a constant velocity difference between the boundaries, considered as thermally insulated. The effect of viscous dissipation induces a heat source in the flow domain and, hence, a temperature gradient. The nonuniform temperature distribution causes, in turn, a buoyancy force and a combined forced and free flow regime. Dual mixed convection flows occur for a given velocity difference. Their structure is analysed where, in general, only one branch of the dual flows is compatible with the Oberbeck-Boussinesq approximation, for realistic values of the Gebhart number. A linear stability analysis of the basic stationary flows with viscous dissipation is carried out. The stability eigenvalue problem is solved numerically, leading to the determination of the neutral stability curves and the critical values of the P\'eclet number, for different Gebhart numbers. An analytical asymptotic solution in the special case of perturbations with infinite wavelength is also developed.Comment: 24 pages, 11 figure

Antilisterial active compound from lactic acid bacteria present on fresh iceberg lettuce

Pediococcus pentosaceus DT016, a bacteriocin producing strain, was isolated from fresh lettuce. A protein with antilisterial activity (bacDT016), between 11 to 17 kDa, was identified and characterized as the bioactive substance from the LAB culture. Highest bacteriocin production was noted after 15 h of growth. Antibacterial activity was affected by some enzymes and detergents, as well as by temperatures equal or above 80 ºC. DT016 strain contains an 1110 bp DNA fragment with homology to pediocin AcH/PA-1

Faithful Squashed Entanglement

Squashed entanglement is a measure for the entanglement of bipartite quantum states. In this paper we present a lower bound for squashed entanglement in terms of a distance to the set of separable states. This implies that squashed entanglement is faithful, that is, strictly positive if and only if the state is entangled. We derive the bound on squashed entanglement from a bound on quantum conditional mutual information, which is used to define squashed entanglement and corresponds to the amount by which strong subadditivity of von Neumann entropy fails to be saturated. Our result therefore sheds light on the structure of states that almost satisfy strong subadditivity with equality. The proof is based on two recent results from quantum information theory: the operational interpretation of the quantum mutual information as the optimal rate for state redistribution and the interpretation of the regularised relative entropy of entanglement as an error exponent in hypothesis testing. The distance to the set of separable states is measured by the one-way LOCC norm, an operationally-motivated norm giving the optimal probability of distinguishing two bipartite quantum states, each shared by two parties, using any protocol formed by local quantum operations and one-directional classical communication between the parties. A similar result for the Frobenius or Euclidean norm follows immediately. The result has two applications in complexity theory. The first is a quasipolynomial-time algorithm solving the weak membership problem for the set of separable states in one-way LOCC or Euclidean norm. The second concerns quantum Merlin-Arthur games. Here we show that multiple provers are not more powerful than a single prover when the verifier is restricted to one-way LOCC operations thereby providing a new characterisation of the complexity class QMA.Comment: 24 pages, 1 figure, 1 table. Due to an error in the published version, claims have been weakened from the LOCC norm to the one-way LOCC nor

A reversible theory of entanglement and its relation to the second law

We consider the manipulation of multipartite entangled states in the limit of many copies under quantum operations that asymptotically cannot generate entanglement. As announced in [Brandao and Plenio, Nature Physics 4, 8 (2008)], and in stark contrast to the manipulation of entanglement under local operations and classical communication, the entanglement shared by two or more parties can be reversibly interconverted in this setting. The unique entanglement measure is identified as the regularized relative entropy of entanglement, which is shown to be equal to a regularized and smoothed version of the logarithmic robustness of entanglement. Here we give a rigorous proof of this result, which is fundamentally based on a certain recent extension of quantum Stein's Lemma proved in [Brandao and Plenio, Commun. Math. 295, 791 (2010)], giving the best measurement strategy for discriminating several copies of an entangled state from an arbitrary sequence of non-entangled states, with an optimal distinguishability rate equal to the regularized relative entropy of entanglement. We moreover analyse the connection of our approach to axiomatic formulations of the second law of thermodynamics.Comment: 21 pages. revised versio

On the stability of the isoflux Darcy–Bénard problem with a generalised basic state

none5siThe scope of this study is to determine the conditions for the onset of the instability in a horizontal porous layer subject to isoflux boundary conditions and with an infinitely wide single–cell basic flow. When the circulation in the basic cellular flow is absent, one recovers the usual Darcy–Bénard conduction basic state. The governing parameters are the Rayleigh number associated with the uniform wall heat flux, and the dimensionless horizontal temperature gradient. The latter parameter controls the magnitude of the basic cellular circulation flow in the horizontal direction. The modal analysis of the instability is carried out numerically by employing a pseudo–spectral method, as well as the shooting method for the solution of the stability eigenvalue problem. Neutral stability and the critical conditions for the onset of the convective instability of the basic state are investigated.noneVayssiere Brandão, P.; Barletta, A.; Celli, M.; Alves, L.S. de B.; Rees, D.A.S.Vayssiere Brandão, P.; Barletta, A.; Celli, M.; Alves, L.S. de B.; Rees, D.A.S

An information system for air quality monitoring using mobile sensor networks

Engineering the information system that runs a heterogeneous mobile sensor network is a complex task. In this paper we present the solution that was developed in the context of the ExpoLIS project. The goal of this project is to deploy a network of mobile (low-cost) sensors in city buses. Besides the software that needs to transfer, process, and store sensor data, we also developed a mobile application to increase awareness on air pollution, and a tool that allows scientists to subscribe to sensor data. We present the engineering solutions that form the backbone of the information system, and the structure and design of developing supporting tools. We discuss our choices regarding how sensor data are processed in order to make these data available for the common citizen. We mention possible future directions for the software that we have developed.info:eu-repo/semantics/acceptedVersio

Avaliação de protocolos hormonais de seis, nove e doze dias sobre o estro, ovulação e fertilidade de cabras da raça Toggenburg em anestro.

O objetivo deste estudo foi avaliar as taxas de ovulação e gestação, após o uso de dispositivos intraginais de progesterona (CIDR) 6, 9 e 12 dias, em cabras em anestro. Os animais (n=51) utilizados, foram distribuídos homogeneamente em dois grupos. Cada grupo era composto or 3 tratamentos , T1 o CIDR permaneceu por seis dias; T2 nove dias com o CIDR e T3 seis dias com o CIDR. As cabras receberam uma dose de 10 mg de dinoprost no dia de inserção do implante e 200 IU de eCG 24 horas antes da retirada do CIDR. As fêmeas no G1 foram cobertas naturalmente e no G2 as fêmeas foram inseminadas em tempo fixo. O período entre o início do estro e a ovulação no G1 foi de 23,3 ± 4,08 horas e de 15,47 ± 4,08 horas no G2. A percentagem de animais que ovularam foi de 100% no G1 e no G2 foi de 85%, 71% e 71% para T1, T2 e T3, respectivamente, mas não foi observado diferença (p=0,05) entre os tratamentos A taxa de gestação no G1 foi de 60%, 70% e 40% para T1, T2e T3, respectivamente, no G2, 50%, 80 % e 60% para T1, T2 e T3, respectivamente, sem haver diferenças entre os tratamentos e entre os grupos. A indução e a sincronização de estro em cabras com CIDR no período de anestro, independente do tempo de exposição a progesterona resulta em uma boa fertilidade, tanto na monta natural quanto também na IATF. Efectos del protocolos hormonales del seis, nueve o doce días sobre celo, la ovulación y la fertilidad en las cabras Toggenburg en anestrous estacionales. Abstract -The aim of the study was to evaluate the rates of ovulation and pregnancy, after the use of controlled internal drug release device impregnated with progesterone (CIDR) 6, 9 and 12 days, in anoestrus season. Animals (n=51) were used, distributed homogeneously into 2 groups (G1 = 30 animals and G2 = 21 animals). Each group had 3 treatments, T1 remained 6 days with CIDR®; treatment T2 9 days with CIDR and T3 6 days with CIDR. The goats received dose of 10 mg of dinoprost on the insertion of the device in 200 IU of eCG 24 hours before the removal of CIDR. The method of mating was covered by natural insemination in G1 and AIFT in G2. The period that includes the start of estrus to ovulation was in G1 23.3 ± 4.08 hours and 15.47 ± 4.08 hours to G2. The percentage of animals that had ovulation was 100% in G1 and G2, 85%, 71% and 71% for T1, T2 and T3, respectively, But there was no significant difference (p=0.05) between treatments. The pregnancies of G1 had 60%, 70% and 40% for T1, T2 and T3, respectively in G2, 50%, 80 % and 60% for T1, T2 and T3, respectively, with no statistical difference between treatments and between groups. The induction and synchrony of estrus in goats with CIDR in the period of anoestrus season, independent of the time of exposure to P4 result in good fertility, natural mated and in AIFT

A two-step factorial design for optimization of protein extraction from industrial rapeseed meal after ethanol-assisted reduction of antinutrients

Rapeseed meal is a by-product of oil production with relatively high antinutrient content which limits its application in both feed and food industries. A two-step procedure, including two-level full factorial and central composite designs, was used to assess the influence of five factors namely pH (6 and 12), temperature (20 and 40 degrees C), NaCl concentration (0 and 7.5%), rapeseed meal concentration (2.5 and 5%), and extraction longevity (15 and 60 min) on protein extraction from industrial rapeseed meal subjected to ethanol-assisted reduction of antinutrients. Data demonstrated that pH and its interaction with NaCl influenced protein extractability the most. While still significant, individual effects of NaCl, extraction longevity, temperature and its interaction with pH had a less significant effect on protein yield. Overall. higher protein yields were obtained in response to combining high pH values with low NaCl concentrations, and high pH values with high temperatures. The highest protein yield (59.56 +/- 1.29%) was achieved after extraction of 5% ethanol-treated rapeseed meal at pH 12 with no NaCl addition, at 40 degrees C and extraction longevity of 60 min. A second-order polynomial model for protein yield prediction was generated. The adequacy of the model was verified by coefficient of determination and residual analyses. A high correlation between experimentally obtained and predicted protein yields (R-2 = 0.95) was established. Since extraction conditions are strong determinants of protein characteristics, the predictive model generated in the present work is useful for the selection of factor combinations, which allows for the achievement of optimal protein yield of a product with desired techno-functional properties.info:eu-repo/semantics/publishedVersio

Preovulatory follicle dynamics in Toggenburg goats after treatment with intravaginal implants of progesterone for 6, 9 or 12 days.

Edição dos Abstracts do II International Symposium on animal Biology or Reproduction, São Paulo, nov. 2008