153 research outputs found
Emergence of the pointer basis through the dynamics of correlations
We use the classical correlation between a quantum system being measured and
its measurement apparatus to analyze the amount of information being retrieved
in a quantum measurement process. Accounting for decoherence of the apparatus,
we show that these correlations may have a sudden transition from a decay
regime to a constant level. This transition characterizes a non-asymptotic
emergence of the pointer basis, while the system-apparatus can still be quantum
correlated. We provide a formalization of the concept of emergence of a pointer
basis in an apparatus subject to decoherence. This contrast of the pointer
basis emergence to the quantum to classical transition is demonstrated in an
experiment with polarization entangled photon pairs.Comment: 4+2 pgs, 3 figures. Title changed. Revised version to appear on PR
Experimental investigation of dynamical invariants in bipartite entanglement
The non-conservation of entanglement, when two or more particles interact,
sets it apart from other dynamical quantities like energy and momentum. It does
not allow the interpretation of the subtle dynamics of entanglement as a flow
of this quantity between the constituents of the system. Here we show that
adding a third party to a two-particle system may lead to a conservation law
that relates the quantities characterizing the bipartite entanglement between
each of the parties and the other two. We provide an experimental demonstration
of this idea using entangled photons, and generalize it to N-partite GHZ
states
Utilización de inmunoreacciones para la detección de Scrapie en Óbex de ovinos provenientes de la XII Región de Chile
Scrapie is an neurodegenerative and infectious disease that affects sheep and goats. The purpose of this study is to compare both tecniques, ELISA and IHC, to determine the application factibility giving the conditions of the laboratory in the country. To develop this assay, fourty obex samples were taken from sheep of the XII Region of Chile and were processed for both techniques ELISA and IHC. The results showed 100% of the samples negative for Scrapie, using both diagnostic methods. Based in obtained and previously reported results, ELISA technique can be recommended to use in massive screening, since yields reliable and rapid test results and IHC is a confirmatory technique. Both techniques are necessary in the creation of current epidemiological surveillance programs in Chile. ELISA and IHC are easily performed given the current laboratories conditions of the Chilean country. El Scrapie es una enfermedad infecciosa neurodegenerativa que afecta a ovinos y caprinos. Dada la importancia que tiene esta enfermedad es que se desarrolló este estudio enmarcado en la comparación de la técnica de ELISA y la de inmunohistoquímica en el diagnóstico de Scrapie, para determinar la factibilidad de aplicarlas en las condiciones de laboratorio país. Para ello se procesaron 40 muestras de óbex de ovinos en duplicado, provenientes de la XII Región de Chile, las cuales fueron sometidas paralelamente a la técnica de ELISA e IHQ. Como resultados se obtuvo un 100% de muestras negativas a Scrapie, sometidas a ambos métodos diagnósticos. Con los valores informados previamente y los obtenidos en esta investigación, es posible recomendar el ELISA como una técnica utilizable en muestreos masivos, ya que aporta resultados confiables de manera más rápida. La IHQ corresponde a una técnica confirmatoria y que ambas, son necesarias en la creación de programas de vigilancia epidemiológica activa en Chile, siendo factibles de realizar en las actuales condiciones de laboratorio país.
Effect of the age of broodstock males on sperm function during cold storage in the trout (Oncorhynchus mykiss)
The knowledge of sperm quality in the broodstock males of different ages is a prerequisite to identify the reproductive ability of cultivated fish for the hatchery management. Thus, in this work, we analysed sperm function of the semen stored of broodstock males of rainbow trout (Oncorhychus mykiss) in different reproductive ages (2, 3 and 4years old). Sperm samples of each reproductive age were stored in Storfish((R)) during 10days at 4 degrees C, and then, motility, viability, mitochondrial function (MMP), superoxide anion (O-2(-)) level and DNA fragmentation (DNA(frag)) were assessed. The results demonstrated that sperm function parameters were affected significantly by the age of the males and the time of storage. Motility, viability and MMP significantly decreased, and DNA(frag) and O-2(-) level increased with the age increment and the time of storage. In conclusion, sperm quality of 2 and 3years old were superior to those of 4years old, based on higher quality of various sperm functions such as motility, viability, MMP, DNA integrity and level O-2(-) during short-term storage. This information must be considered for optimum utilization of broodstock males in aquacultur
Lifetime calculations in energy levels of Kr VII
Calculations of the lifetimes for all experimentally known energy levels of the spectrum of the six times-ionized krypton (Kr VII) are presented. The relativistic Hartree–Fock method including corepolarization effects were used. The energy matrix was calculated using energy parameters adjusted to the experimental energy levels.Wealso present a calculation based on a relativistic multiconfigurational Dirac–Fock approach. For some energy levels, a comparison of these results with the bibliography data was made
Optimization of the efficiency in an induction machine drive by algorithm based on the interior point method
[EN] This work optimizes the efficiency of the squirrel cage type Inverter-Induction Machine (IM) system, using an algorithm based on the Interior Point Method (IPM), where the input variables are the electromagnetic torque and the rotor speed at steady state,and as outputs the optimal efficiency and slip values are obtained. The optimum rotor flux value is calculated, which is used as a reference in the flux control loop, in the direct control vector method of the IM. Simulation results are obtained where the increase in efficiency is observed in low load states. The experimental installation used in the implementation of the vector control with maximum system efficiency is described, and the experimental results obtained are shown. A discussion is carried out on the results and the use of the Interior Point Optimization Method.[ES] En este trabajo se realiza la optimización de la eficiencia del sistema Inversor-Máquina de Inducción (MI) del tipo jaula de ardilla, utilizando un algoritmo basado en el Método de Punto Interior (MPI), donde las variables de entrada son el par electromagnético y la velocidad del rotor en estado estacionario, y como salidas se obtienen los valores de la eficiencia óptima y del deslizamiento. Se calcula el valor del flujo óptimo del rotor que se utiliza como referencia en el lazo de control del flujo, en el control vectorial método directo de la MI. Se obtienen resultados de simulación donde se observa el incremento de la eficiencia en estados de baja carga. Se describe la instalación experimental usada en la implementación del control vectorial con máxima eficiencia del sistema, y se muestran los resultados experimentales obtenidos. Se realiza una discusión sobre los resultados y la utilización del Método de Optimización de Punto Interior.Instituto Politécnico Nacional (IPN), proyecto multidisciplinario registro número 1995.Pacheco-Montiel, J.; Badaoui, M.; Rodríguez-Rivas, J.; Alvarado-Farías, JM.; Carranza-Castillo, O.; Ortega-González, R. (2021). Optimización de la eficiencia en el accionamiento de una máquina de inducción mediante algoritmo basado en el método de punto interior. Revista Iberoamericana de Automática e Informática industrial. 18(4):336-346. https://doi.org/10.4995/riai.2020.13418OJS336346184Andréasson, N., Evgrafov, A., Patriksson, M, 2020. An Introduction to Continuous Optimization Fundations & Fundamental Algorithms. Dover Publications.Benson, H. Y., Shanno, D. F, 2014. Interior-point methods for nonconvex nonlinear programming: cubic regularization. Comput Optim Appl, 58:323-346. https://doi.org/10.1007/s10589-013-9626-8Borisevich, A., and Schullerus, G, 2016. Energy Efficient Control of an Induction Machine Under Torque Step Changes. IEEE Trans. on Energy Conv., vol. 31, no. 4, pp. 1295-1303, December. https://doi.org/10.1109/TEC.2016.2561307Capitanescu, F., Wehenkel, L., 2013. Experiments with the interior-point method for solving large scale optimal power flow problems. Electric Power Systems Research, vol. 95, pp. 276-283. https://doi.org/10.1016/j.epsr.2012.10.001Casacio, L., Lyra, C., Oliveira, A.R.L, 2019. Interior point methods for power flow optimization with security constraints. Intl. Trans. in Op. Res. 26 (2019) 364-378. https://doi.org/10.1111/itor.12279Colín, E. A. O., González, I. H. G., Rivas, J. J. R., Castillo, O. C., González, R. O., Caporal, R. M., 2017. Implementación del Algoritmo Sünter-Clare en un Convertidor Matricial 3x3. Revista Iberoamericana de Automática e Informática Industrial (RIAI), vol. 14, no. 4, pp. 446-454, Oct.-Dic. https://doi.org/10.1016/j.riai.2017.06.002De Almeida, A. T., Ferreira, F. J. T. E., Duarte, A. Q, 2014. Technical and Economical Considerations on Super High-Efficiency Three-Phase Motors. IEEE Trans. on Ind. App., vol. 50, no. 2, pp. 1274-1285, March/April. https://doi.org/10.1109/TIA.2013.2272548Eftekhari, S. R., Davari, S. A., Naderi, P., García C., Rodriguez, J, 2020. Robust Loss Minimization for Predictive Direct Torque and Flux Control of an Induction Motor With Electrical Circuit Model. IEEE Trans. on Power Electronics, vol. 35, no. 5, pp. 5417-5426, May. https://doi.org/10.1109/TPEL.2019.2944190Farhat, I. A., El-Hawary, M. E, 2009. Interior point methods application in optimum operational scheduling of electric power systems. IET Generation, Transmission & Distribution, vol. 3, Iss. 11, pp. 1020-1029. https://doi.org/10.1049/iet-gtd.2008.0573IEA International Energy Agency. World Energy Outlook, 2018. IEA, Paris 2018. 01/2020. https://www.iea.org/reports/world-energy-outlook-2018.IEC 60034-30-1, 2014. Efficiency classes of line operated AC motors (IE-code), Edition 1.0.Mallik, S., Mallik, K., Barman, A., Maiti, D., Biswas, S. K., Deb, N. K., Basu, S, 2017. Efficiency and Cost Optimized Design of an Induction Motor Using Generic Algorithm. IEEE Trans. on Ind. Appl., vol. 64, no. 12, pp. 9854-9863, December. https://doi.org/10.1109/TIE.2017.2703687McElveen, R., Melfi, M., McFarland, J, 2019. Improved Characterization of Polyphase Induction Motor Losses: Test Standards Must Be Modified to Improve Efficiency Optimization. IEEE Ind. Appl. Magazine., pp. 61-68, Nov./Dec. https://doi.org/10.1109/MIAS.2018.2875208Rao, N., and Chamund, D, 2014. Calculating Power Losses in an IGBT Module. Application Note. DYNEX Power Control through Innovation.Rathore, A. K., Holtz, J., Boller, T, 2013. Generalized Optimal Pulsewidth Modulation of Multilevel Inverters for Low-Switching-Frequency Control of Medium-Voltage High-Power Industrial AC Drives. IEEE Trans. on Ind. Electronics, vol. 60, no. 10, pp. 4215-4224, Oct. https://doi.org/10.1109/TIE.2012.2217717Seung-Ki, S, 2011. Control of Electric Machine Drive Systems. IEEE Press & Wiley. Printed in the USA.Salomon, C. P., Sant'Ana, W. C., Borges da Silva, L. E., Torres, G. L., Bonaldi, E. L., Olveira, L. E. L., Borges da Silva, J. G, 2015. Induction Motor Efficiency Evaluation Using a New Concept of Stator Resistance. IEEE Trans. on Inst. and Meas., vol. 64, no. 11, pp. 2908-2917, November. https://doi.org/10.1109/TIM.2015.2437632Santos, V. S., Felipe, P. R. V, Sarduy, J. R. G., Lemozy, N. A. L., Jurado, A., Quispe, E. C, 2015. Procedure for Determining Induction Motor Efficiency Working Under Distorted Grid Voltages. IEEE Trans. on Energy Conv., vol. 30, no. 1, pp. 331-339, March. https://doi.org/10.1109/TEC.2014.2335994Shukla, S., and Singh, B, 2017. Solar Powered Sensorless Induction Motor Drive with Improved Efficiency forWater Pumping. IET Power Electronics, vol. 11, issue 3, pp. 1-11, March. https://doi.org/10.1049/iet-pel.2017.0452Stumper, J. F., Dötlinger, A., Kennel, R, 2013. Loss Minimization of Induction Machines in Dynamic Operation. IEEE Trans. on Energy Conv., vol. 28, no. 3, pp. 726-735, September. https://doi.org/10.1109/TEC.2013.2262048Sul, S. K., 2011. Control of Electric Machine Drive Systems. IEEE Press-Wiley & Sons. https://doi.org/10.1002/9780470876541Taheri, A., Rahmati, A., Kaboli, S, 2012. Efficiency Improvement in DTC of Six-Phase Induction Machine by Adaptive Gradient Descent of Flux. IEEE Trans. on Power Electronics, vol. 27, no. 3, pp. 1552-1562, March. https://doi.org/10.1109/TPEL.2011.2163420Vanderbei, R. J., Shanno, D. F, 1999. Interior-point methods for nonconvex nonlinear programming. Computational Optimization and Applications, 13, 31-252. https://doi.org/10.1023/A:1008677427361Vural, A. M, 2015. Interior point-based slack-bus free-power flow solution for balanced islanded microgrids. Int. Trans. Electr. Energ. Syst, 26:968-992. https://doi.org/10.1002/etep.2117Xu, W., Hu, D., Lei, G., Zhu, J, 2019. System-Level Efficiency Optimization of a Linear Induction Motor Drive System. IEEE Trans. on Electrical Machines and Systems, vol. 3, no. 3, pp. 285-291, Sept. https://doi.org/10.30941/CESTEMS.2019.00037Xu, W., Xiao, X., Du, G., Zou, J, 2020. Comprehensive Efficiency Optimization of Linear Induction Motors for Urban Transit. IEEE Trans. on Vehicular Tech., vol. 69, no. 1, pp. 131-139, January. https://doi.org/10.1109/TVT.2019.295395
Syndecan 4 interacts genetically with Vangl2 to regulate neural tube closure and planar cell polarity
Syndecan 4 (Sdc4) is a cell-surface heparan sulfate proteoglycan (HSPG) that regulates gastrulation, neural tube closure and directed neural crest migration in Xenopus development. To determine whether Sdc4 participates in Wnt/PCP signaling during mouse development, we evaluated a possible interaction between a null mutation of Sdc4 and the loop-tail allele of Vangl2. Sdc4 is expressed in multiple tissues, but particularly in the non-neural ectoderm, hindgut and otic vesicles. Sdc4;Vangl2Lp compound mutant mice have defective spinal neural tube closure, disrupted orientation of the stereocilia bundles in the cochlea and delayed wound healing, demonstrating a strong genetic interaction. In Xenopus, co-injection of suboptimal amounts of Sdc4 and Vangl2 morpholinos resulted in a significantly greater proportion of embryos with defective neural tube closure than each individual morpholino alone. To probe the mechanism of this interaction, we overexpressed or knocked down Vangl2 function in HEK293 cells. The Sdc4 and Vangl2 proteins colocalize, and Vangl2, particularly the Vangl2Lp mutant form, diminishes Sdc4 protein levels. Conversely, Vangl2 knockdown enhances Sdc4 protein levels. Overall HSPG steady-state levels were regulated by Vangl2, suggesting a molecular mechanism for the genetic interaction in which Vangl2Lp/+ enhances the Sdc4-null phenotype. This could be mediated via heparan sulfate residues, as Vangl2Lp/+ embryos fail to initiate neural tube closure and develop craniorachischisis (usually seen only in Vangl2Lp/Lp) when cultured in the presence of chlorate, a sulfation inhibitor. These results demonstrate that Sdc4 can participate in the Wnt/PCP pathway, unveiling its importance during neural tube closure in mammalian embryos
Modulated Entanglement Evolution Via Correlated Noises
We study entanglement dynamics in the presence of correlated environmental
noises. Specifically, we investigate the quantum entanglement dynamics of two
spins in the presence of correlated classical white noises, deriving Markov
master equation and obtaining explicit solutions for several interesting
classes of initial states including Bell states and X form density matrices. We
show how entanglement can be enhanced or reduced by the correlation between the
two participating noises.Comment: 9 pages, 4 figures. To be published in Quantum Information
Processing, special issue on Quantum Decoherence and Entanglemen
Characterization of Microbialites and Microbial Mats of the Laguna Negra Hypersaline Lake (Puna of Catamarca, Argentina)
Microbial carbonates provide an invaluable tool to understand biogeochemical processes in aqueous systems, especially in lacustrine and marine environments. Lakes are strongly sensitive to climatically driven environmental changes, and microbialites have recently been shown to provide a record of these changes. Unraveling physicochemical and microbiological controls on carbonates textures and geochemistry is necessary to correctly interpret these signals and the microbial biosphere record within sedimentary carbonates. The Laguna Negra is a high-altitude hypersaline Andean lake (Puna of Catamarca, Argentina), where abundant carbonate precipitation takes place and makes this system an interesting example that preserves a spectrum of carbonate fabrics reflecting complex physical, chemical, and biological interactions. The extreme environmental conditions (high UV radiation, elevated salinity, and temperature extremes) make the Laguna Negra a good analogue to some Precambrian microbialites (e.g., Tumbiana Fm., Archean, Australia). In addition, the discovery of ancient evaporating playa-lake systems on Mars’ surface (e.g., ShalbatanaVallis, Noachian, Mars) highlights the potential of Laguna Negra to provide insight into biosignature preservation in similar environments, in both terrestrial and extraterrestrial settings, given that microbial processes in the Laguna Negra can be studied with remarkable detail.Fil: Boidi, Flavia Jaquelina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Centro de Investigaciones en Ciencias de la Tierra. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Centro de Investigaciones en Ciencias de la Tierra; ArgentinaFil: Mlewski, Estela Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Centro de Investigaciones en Ciencias de la Tierra. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Centro de Investigaciones en Ciencias de la Tierra; ArgentinaFil: Gomez, Fernando Javier. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Centro de Investigaciones en Ciencias de la Tierra. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Centro de Investigaciones en Ciencias de la Tierra; ArgentinaFil: Gérard, Emmanuelle. Centre National de la Recherche Scientifique; Franci
Equation of motion for entanglement
We review an evolution equation for quantum entanglement for 2x2 dimensional
quantum systems, the smallest system that can exhibit entanglement, and extend
it to higher dimensional systems. Furthermore, we provide statistical evidence
for the equation's applicability to the experimentally relevant domain of
weakly mixed states.Comment: 7 pages, 3 figures, published versio
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