335 research outputs found

    Producción de emulsiones submicrónicas formuladas con dos biodisolventes y tres tensioactivos ecológicos diferentes

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    El objetivo de este trabajo fue comparar las propiedades emulsionantes de tres tensioactivos ecológicos que derivan del aceite de coco para la preparación de emulsiones aceite-en-agua formuladas con una mezcla de disolventes verdes como fase dispersa, N,Ndimetildecanamiday a-pineno. La reología, la difracción láser, la microscopía óptica y el “multiple lightscattering” fueron las técnicas principales utilizadas para evaluar las propiedades emulsionantes de estos tensioactivos. Se obtuvieron emulsiones ligeramente concentradas usando cualquiera de los tensio activos estudiados, que difieren en el número de grupos etoxilados.Sin embargo, se ha demostrado que el uso del tensioactivo no-iónico con el mayor número de grupos etoxilados (Levenol C201) es adecuado por tresmotivos: (a) permite obtener los menores tamaños degota, (b) proporciona suficiente viscosidad para prevenirel cremado y (c) no se produce desestabilización por coalescencia. La caracterización sistemática quese presenta en este trabajo proporciona importantes resultados sobre las propiedades emulsionantes de los ésteres polietoxilados de glicerina derivados del aceitede coco, que pueden ser utilizados para el desarrollo de nuevos productos biocompatibles

    Algorithms for Game Metrics

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    Simulation and bisimulation metrics for stochastic systems provide a quantitative generalization of the classical simulation and bisimulation relations. These metrics capture the similarity of states with respect to quantitative specifications written in the quantitative {\mu}-calculus and related probabilistic logics. We first show that the metrics provide a bound for the difference in long-run average and discounted average behavior across states, indicating that the metrics can be used both in system verification, and in performance evaluation. For turn-based games and MDPs, we provide a polynomial-time algorithm for the computation of the one-step metric distance between states. The algorithm is based on linear programming; it improves on the previous known exponential-time algorithm based on a reduction to the theory of reals. We then present PSPACE algorithms for both the decision problem and the problem of approximating the metric distance between two states, matching the best known algorithms for Markov chains. For the bisimulation kernel of the metric our algorithm works in time O(n^4) for both turn-based games and MDPs; improving the previously best known O(n^9\cdot log(n)) time algorithm for MDPs. For a concurrent game G, we show that computing the exact distance between states is at least as hard as computing the value of concurrent reachability games and the square-root-sum problem in computational geometry. We show that checking whether the metric distance is bounded by a rational r, can be done via a reduction to the theory of real closed fields, involving a formula with three quantifier alternations, yielding O(|G|^O(|G|^5)) time complexity, improving the previously known reduction, which yielded O(|G|^O(|G|^7)) time complexity. These algorithms can be iterated to approximate the metrics using binary search.Comment: 27 pages. Full version of the paper accepted at FSTTCS 200

    Simulation-Based Graph Similarity

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    We present symmetric and asymmetric similarity measures for labeled directed rooted graphs that are inspired by the simulation and bisimulation relations on labeled transition systems. Computation of the similarity measures has close connections to discounted Markov decision processes in the asymmetric case and to perfect-information stochastic games in the symmetric case. For the symmetric case, we also give a polynomial-time algorithm that approximates the similarity to any desired precision

    First report of Tomato torrado virus on weed hosts in Spain

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    Alfaro Fernández, AO.; Córdoba-Sellés, C.; Cebrián, M.; Herrera-Vásquez, J.; Sanchez Navarro, JA.; Juárez, M.; Espino, A.... (2088). First report of Tomato torrado virus on weed hosts in Spain. Plant Disease. 92(5):831-831. https://doi.org/10.1094/pdis-92-5-0831b83183192

    O USO DO ALUMINOSSILICATO (SILVET®) COMO ADJUVANTE NA MELHORA DO ASPECTO DAS FEZES E DESEMPENHO DAS AVES

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    O controle da umidade da cama na criação comercial de aves é essencial, especialmente no verão, quando há maior ingestão de água pelas aves e as fezes ficam muito liqüefeitas. Uma solução é incorporar substâncias adsorventes de água na dieta, como aluminossilicato, que reduz a água livre e proporciona menor umidade na cama. Este estudo teve por objetivo avaliar se o aluminossilicato pode melhorar o aspecto das fezes ao ser adicionado na ração de frangos. Foi realizado numa granja comercial em São José dos Pinhais-PR, utilizando-se dois tratamentos e quatro repetições com 25 aves cada. No primeiro tratamento adicionou-se 1% de aluminossilicato (SilvetÒ) à dieta, no segundo, o produto estava ausente. Dos 3 aos 40 dias de vida as aves receberam ração e água ad libitum, sendo pesadas aos 22 e 40 dias e avaliadas quanto consumo de ração, ganho de peso e conversão alimentar. Realizou-se também necropsia de 4 aves por tratamento, para observação de possíveis lesões macroscópicas e colheita dos conteúdos intestinais que foram enviados para análise de umidade total e cinzas. Os resultados foram submetidos a ANOVA, não havendo diferenças significativas quanto ao desempenho das aves entre os tratamentos, entretanto, em ambas as idades as porcentagens de cinzas e umidade total foram maiores nas aves que receberam aluminossilicato. A inclusão do aluminossilicato na dieta não influencia no desempenho das aves, porém melhora o aspecto fecal, aumentando a quantidade de matéria seca e reduzindo a umidade livre nas fezes excretadas. The use of aluminossilicate (silvet®) as an adjuvant in broiler feces aspect and performance improvement Abstract The control of bed humidity in the creations of r commercial broiler chicken is essential, especially in the summer, when there is a larger ingestion of water the feces becoming more liquefied. The incorporation of water adsorptive substances to the diet, such as the aluminossilicate, reduces the free water and provides lower humidity in the bed. This study was carried out to evaluate the use of aluminossilicate on feces aspect. Two treatments and four repetitions with 25 chicks each were performed in a commercial farm in São José dos Pinhais-PR. At the first treatment 1% of aluminossilicate was added (SilvetÒ) to the diet, while the product was absent in the other. From 3 to 40 days of life the chicks received ration and water ad libitum and were weighted at days 22 and 40 and evaluated over ration consumption, bodyweight gain and alimentary conversion. Necropsy of 4 chicks per treatment was carried out in order to detect possible macroscopic lesions, collect intestinal contents and analyze total humidity and ashes content in the feces. The results submitted to the statistical method ANOVA, did not show expressive differences between the treatments for animal performance. However, in both ages the total humidity and ash percentage were higher on broiler that received aluminossilicate. Aluminossilicate inclusion on diet did not influence in the broiler performance, although it improved the feces aspect by increasing the drought matter quantity and reducing the feces free humidity

    O USO DO ALUMINOSSILICATO (SILVET®) COMO ADJUVANTE NA MELHORA DO ASPECTO DAS FEZES E DESEMPENHO DAS AVES

    Get PDF
    O controle da umidade da cama na criação comercial de aves é essencial, especialmente no verão, quando há maior ingestão de água pelas aves e as fezes ficam muito liqüefeitas. Uma solução é incorporar substâncias adsorventes de água na dieta, como aluminossilicato, que reduz a água livre e proporciona menor umidade na cama. Este estudo teve por objetivo avaliar se o aluminossilicato pode melhorar o aspecto das fezes ao ser adicionado na ração de frangos. Foi realizado numa granja comercial em São José dos Pinhais-PR, utilizando-se dois tratamentos e quatro repetições com 25 aves cada. No primeiro tratamento adicionou-se 1% de aluminossilicato (SilvetÒ) à dieta, no segundo, o produto estava ausente. Dos 3 aos 40 dias de vida as aves receberam ração e água ad libitum, sendo pesadas aos 22 e 40 dias e avaliadas quanto consumo de ração, ganho de peso e conversão alimentar. Realizou-se também necropsia de 4 aves por tratamento, para observação de possíveis lesões macroscópicas e colheita dos conteúdos intestinais que foram enviados para análise de umidade total e cinzas. Os resultados foram submetidos a ANOVA, não havendo diferenças significativas quanto ao desempenho das aves entre os tratamentos, entretanto, em ambas as idades as porcentagens de cinzas e umidade total foram maiores nas aves que receberam aluminossilicato. A inclusão do aluminossilicato na dieta não influencia no desempenho das aves, porém melhora o aspecto fecal, aumentando a quantidade de matéria seca e reduzindo a umidade livre nas fezes excretadas. The use of aluminossilicate (silvet®) as an adjuvant in broiler feces aspect and performance improvement Abstract The control of bed humidity in the creations of r commercial broiler chicken is essential, especially in the summer, when there is a larger ingestion of water the feces becoming more liquefied. The incorporation of water adsorptive substances to the diet, such as the aluminossilicate, reduces the free water and provides lower humidity in the bed. This study was carried out to evaluate the use of aluminossilicate on feces aspect. Two treatments and four repetitions with 25 chicks each were performed in a commercial farm in São José dos Pinhais-PR. At the first treatment 1% of aluminossilicate was added (SilvetÒ) to the diet, while the product was absent in the other. From 3 to 40 days of life the chicks received ration and water ad libitum and were weighted at days 22 and 40 and evaluated over ration consumption, bodyweight gain and alimentary conversion. Necropsy of 4 chicks per treatment was carried out in order to detect possible macroscopic lesions, collect intestinal contents and analyze total humidity and ashes content in the feces. The results submitted to the statistical method ANOVA, did not show expressive differences between the treatments for animal performance. However, in both ages the total humidity and ash percentage were higher on broiler that received aluminossilicate. Aluminossilicate inclusion on diet did not influence in the broiler performance, although it improved the feces aspect by increasing the drought matter quantity and reducing the feces free humidity

    Quantization of the Damped Harmonic Oscillator Revisited

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    We return to the description of the damped harmonic oscillator by means of a closed quantum theory with a general assessment of previous works, in particular the Bateman-Caldirola-Kanai model and a new model recently proposed by one of the authors. We show the local equivalence between the two models and argue that latter has better high energy behavior and is naturally connected to existing open-quantum-systems approaches.Comment: 16 page

    Lepton Flavour Violating Leptonic/Semileptonic Decays of Charged Leptons in the Minimal Supersymmetric Standard Model

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    We consider the leptonic and semileptonic (SL) lepton flavour violating (LFV) decays of the charged leptons in the minimal supersymmetric standard model (MSSM). The formalism for evaluation of branching fractions for the SL LFV charged-lepton decays with one or two pseudoscalar mesons, or one vector meson in the final state, is given. Previous amplitudes for the SL LFV charged-lepton decays in MSSM are improved, for instance the γ\gamma-penguin amplitude is corrected to assure the gauge invariance. The decays are studied not only in the model-independent formulation of the theory in the frame of MSSM, but also within the frame of the minimal supersymmetric SO(10) model within which the parameters of the MSSM are determined. The latter model gives predictions for the neutrino-Dirac Yukawa coupling matrix, once free parameters in the model are appropriately fixed to accommodate the recent neutrino oscillation data. Using this unambiguous neutrino-Dirac Yukawa couplings, we calculate the LFV leptonic and SL decay processes assuming the minimal supergravity scenario. A very detailed numerical analysis is done to constrain the MSSM parameters. Numerical results for SL LFV processes are given, for instance for tau -> e (mu) pi0, tau -> e (mu) eta, tau -> e (mu) eta', tau -> e (mu) rho0, tau -> e (mu) phi, tau -> e (mu) omega, etc.Comment: 36 pages, 3 tables, 5 .eps figure

    Lorentz breaking Effective Field Theory and observational tests

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    Analogue models of gravity have provided an experimentally realizable test field for our ideas on quantum field theory in curved spacetimes but they have also inspired the investigation of possible departures from exact Lorentz invariance at microscopic scales. In this role they have joined, and sometime anticipated, several quantum gravity models characterized by Lorentz breaking phenomenology. A crucial difference between these speculations and other ones associated to quantum gravity scenarios, is the possibility to carry out observational and experimental tests which have nowadays led to a broad range of constraints on departures from Lorentz invariance. We shall review here the effective field theory approach to Lorentz breaking in the matter sector, present the constraints provided by the available observations and finally discuss the implications of the persisting uncertainty on the composition of the ultra high energy cosmic rays for the constraints on the higher order, analogue gravity inspired, Lorentz violations.Comment: 47 pages, 4 figures. Lecture Notes for the IX SIGRAV School on "Analogue Gravity", Como (Italy), May 2011. V.3. Typo corrected, references adde

    Implications of early respiratory support strategies on disease progression in critical COVID-19: a matched subanalysis of the prospective RISC-19-ICU cohort.

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    Uncertainty about the optimal respiratory support strategies in critically ill COVID-19 patients is widespread. While the risks and benefits of noninvasive techniques versus early invasive mechanical ventilation (IMV) are intensely debated, actual evidence is lacking. We sought to assess the risks and benefits of different respiratory support strategies, employed in intensive care units during the first months of the COVID-19 pandemic on intubation and intensive care unit (ICU) mortality rates. Subanalysis of a prospective, multinational registry of critically ill COVID-19 patients. Patients were subclassified into standard oxygen therapy ≥10 L/min (SOT), high-flow oxygen therapy (HFNC), noninvasive positive-pressure ventilation (NIV), and early IMV, according to the respiratory support strategy employed at the day of admission to ICU. Propensity score matching was performed to ensure comparability between groups. Initially, 1421 patients were assessed for possible study inclusion. Of these, 351 patients (85 SOT, 87 HFNC, 87 NIV, and 92 IMV) remained eligible for full analysis after propensity score matching. 55% of patients initially receiving noninvasive respiratory support required IMV. The intubation rate was lower in patients initially ventilated with HFNC and NIV compared to those who received SOT (SOT: 64%, HFNC: 52%, NIV: 49%, p = 0.025). Compared to the other respiratory support strategies, NIV was associated with a higher overall ICU mortality (SOT: 18%, HFNC: 20%, NIV: 37%, IMV: 25%, p = 0.016). In this cohort of critically ill patients with COVID-19, a trial of HFNC appeared to be the most balanced initial respiratory support strategy, given the reduced intubation rate and comparable ICU mortality rate. Nonetheless, considering the uncertainty and stress associated with the COVID-19 pandemic, SOT and early IMV represented safe initial respiratory support strategies. The presented findings, in agreement with classic ARDS literature, suggest that NIV should be avoided whenever possible due to the elevated ICU mortality risk
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