A preliminary study in Wistar rats with enniatin : A contaminated feed

A 28-day repeated dose preliminary assay, using enniatin A naturally contaminated feed through microbial fermentation by a Fusarium tricinctum strain, was carried out employing two months-old female Wistar rats as in vivo experimental model. In order to simulate a physiological test of a toxic compound naturally produced by fungi, five treated animals were fed during twenty-eight days with fermented feed. As control group, five rats were fed with standard feed. At the 28th day, blood samples were collected for biochemical analysis and the gastrointestinal tract, liver and kidneys were removed from each rat for enniatin A detection and quantitation. Digesta were collected from stomach, duodenum, jejunum, ileum and colon. Enniatin A present in organs and in biological fluids was analyzed by liquid chromatography-diode array detector (LC-DAD) and confirmed by LC-mass spectrometry linear ion trap (MS-LIT); also several serum biochemical parameters and a histological analysis of the duodenal tract were performed. No adverse effects were found in any treated rat at the enniatin A concentration (20.91 mg/kg bw/day) tested during the 28-day experiment. Enniatin A quantitation in biological fluids ranged from 1.50 to 9.00 mg/kg, whereas in the gastrointestinal organs the enniatin A concentration ranged from 2.50 to 23.00 mg/kg. The high enniatin A concentration found in jejunum liquid and tissue points to them as an absorption area. Finally, two enniatin A degradation products were identified in duodenum, jejunum and colon content, probably produced by gut microflora

Birefringence effects in multi-core fiber: coupled local-mode theory

© 2016 Optical Society of America. One print or electronic copy may be made for personal use only. Systematic reproduction and distribution, duplication of any material in this paper for a fee or for commercial purposes, or modifications of the content of this paper are prohibitedIn this paper, we evaluate experimentally and model theoretically the intra- and inter-core crosstalk between the polarized core modes in single-mode multi-core fiber media including temporal and longitudinal birefringent effects. Specifically, extensive experimental results on a four-core fiber indicate that the temporal fluctuation of fiber birefringence modifies the intra- and inter-core crosstalk behavior in both linear and nonlinear optical power regimes. To gain theoretical insight into the experimental results, we introduce an accurate multi-core fiber model based on local modes and perturbation theory, which is derived from the Maxwell equations including both longitudinal and temporal birefringent effects. Numerical calculations based on the developed theory are found to be in good agreement with the experimental data.This work has been partly funded by Spain National Plan project MINECO/FEDER UE XCORE TEC2015-70858-C2-1-R; HIDRASENSE RTC-2014-2232-3; European Regional Development Fund (ERDF) and the Galician Regional Government under project GRC2015/018. A. Macho and M. Morant work was supported by BES-2013-062952 F.P.I. Grant and postdoc UPV PAID-10-14 program, respectively.Macho-Ortiz, A.; García Meca, C.; Fraile-Peláez, FJ.; Morant Pérez, M.; Llorente Sáez, R. (2016). Birefringence effects in multi-core fiber: coupled local-mode theory. Optics Express. 24(19):21415-21434. https://doi.org/10.1364/OE.24.021415S21415214342419Mizuno, T., Takara, H., Sano, A., & Miyamoto, Y. (2016). Dense Space-Division Multiplexed Transmission Systems Using Multi-Core and Multi-Mode Fiber. Journal of Lightwave Technology, 34(2), 582-592. doi:10.1109/jlt.2015.2482901Morant, M., Macho, A., & Llorente, R. (2016). On the Suitability of Multicore Fiber for LTE–Advanced MIMO Optical Fronthaul Systems. Journal of Lightwave Technology, 34(2), 676-682. doi:10.1109/jlt.2015.2507137Hayashi, T., Sasaki, T., Sasaoka, E., Saitoh, K., & Koshiba, M. (2013). Physical interpretation of intercore crosstalk in multicore fiber: effects of macrobend, structure fluctuation, and microbend. Optics Express, 21(5), 5401. doi:10.1364/oe.21.005401Fini, J. M., Zhu, B., Taunay, T. F., Yan, M. F., & Abedin, K. S. (2012). Statistical Models of Multicore Fiber Crosstalk Including Time Delays. Journal of Lightwave Technology, 30(12), 2003-2010. doi:10.1109/jlt.2012.2188017Luis, R. S., Puttnam, B. J., Cartaxo, A. V. T., Klaus, W., Mendinueta, J. M. D., Awaji, Y., … Sasaki, T. (2016). Time and Modulation Frequency Dependence of Crosstalk in Homogeneous Multi-Core Fibers. Journal of Lightwave Technology, 34(2), 441-447. doi:10.1109/jlt.2015.2474128Hayashi, T., Taru, T., Shimakawa, O., Sasaki, T., & Sasaoka, E. (2012). Characterization of Crosstalk in Ultra-Low-Crosstalk Multi-Core Fiber. Journal of Lightwave Technology, 30(4), 583-589. doi:10.1109/jlt.2011.2177810Fini, J. M., Zhu, B., Taunay, T. F., & Yan, M. F. (2010). Statistics of crosstalk in bent multicore fibers. Optics Express, 18(14), 15122. doi:10.1364/oe.18.015122Koshiba, M., Saitoh, K., Takenaga, K., & Matsuo, S. (2011). Multi-core fiber design and analysis: coupled-mode theory and coupled-power theory. Optics Express, 19(26), B102. doi:10.1364/oe.19.00b102Hayashi, T., Taru, T., Shimakawa, O., Sasaki, T., & Sasaoka, E. (2011). Design and fabrication of ultra-low crosstalk and low-loss multi-core fiber. Optics Express, 19(17), 16576. doi:10.1364/oe.19.016576Koshiba, M., Saitoh, K., Takenaga, K., & Matsuo, S. (2012). Analytical Expression of Average Power-Coupling Coefficients for Estimating Intercore Crosstalk in Multicore Fibers. IEEE Photonics Journal, 4(5), 1987-1995. doi:10.1109/jphot.2012.2221085Macho, A., Morant, M., & Llorente, R. (2015). Experimental evaluation of nonlinear crosstalk in multi-core fiber. Optics Express, 23(14), 18712. doi:10.1364/oe.23.018712Macho, A., Morant, M., & Llorente, R. (2016). Unified Model of Linear and Nonlinear Crosstalk in Multi-Core Fiber. Journal of Lightwave Technology, 34(13), 3035-3046. doi:10.1109/jlt.2016.2552958Mecozzi, A., Antonelli, C., & Shtaif, M. (2012). Coupled Manakov equations in multimode fibers with strongly coupled groups of modes. Optics Express, 20(21), 23436. doi:10.1364/oe.20.023436Mecozzi, A., Antonelli, C., & Shtaif, M. (2012). Nonlinear propagation in multi-mode fibers in the strong coupling regime. Optics Express, 20(11), 11673. doi:10.1364/oe.20.011673Mumtaz, S., Essiambre, R.-J., & Agrawal, G. P. (2013). Nonlinear Propagation in Multimode and Multicore Fibers: Generalization of the Manakov Equations. Journal of Lightwave Technology, 31(3), 398-406. doi:10.1109/jlt.2012.2231401Palmieri, L., & Galtarossa, A. (2014). Coupling Effects Among Degenerate Modes in Multimode Optical Fibers. IEEE Photonics Journal, 6(6), 1-8. doi:10.1109/jphot.2014.2343998Antonelli, C., Mecozzi, A., & Shtaif, M. (2015). The delay spread in fibers for SDM transmission: dependence on fiber parameters and perturbations. Optics Express, 23(3), 2196. doi:10.1364/oe.23.002196Marcuse, D. (1975). Coupled-Mode Theory for Anisotropic Optical Waveguides. Bell System Technical Journal, 54(6), 985-995. doi:10.1002/j.1538-7305.1975.tb02878.xWong, D. (1990). Thermal stability of intrinsic stress birefringence in optical fibers. Journal of Lightwave Technology, 8(11), 1757-1761. doi:10.1109/50.60576Gloge, D. (1971). Weakly Guiding Fibers. Applied Optics, 10(10), 2252. doi:10.1364/ao.10.002252Cartaxo, A. V. T., Luis, R. S., Puttnam, B. J., Hayashi, T., Awaji, Y., & Wada, N. (2016). Dispersion Impact on the Crosstalk Amplitude Response of Homogeneous Multi-Core Fibers. IEEE Photonics Technology Letters, 28(17), 1858-1861. doi:10.1109/lpt.2016.2573925Poole, C. D., & Favin, D. L. (1994). Polarization-mode dispersion measurements based on transmission spectra through a polarizer. Journal of Lightwave Technology, 12(6), 917-929. doi:10.1109/50.296179Karlsson, O., Brentel, J., & Andrekson, P. A. (2000). Long-term measurement of PMD and polarization drift in installed fibers. Journal of Lightwave Technology, 18(7), 941-951. doi:10.1109/50.850739Brodsky, M., Frigo, N. J., Boroditsky, M., & Tur, M. (2006). Polarization Mode Dispersion of Installed Fibers. Journal of Lightwave Technology, 24(12), 4584-4599. doi:10.1109/jlt.2006.88578

Conformal mechanics inspired by extremal black holes in d=4

A canonical transformation which relates the model of a massive relativistic particle moving near the horizon of an extremal black hole in four dimensions and the conventional conformal mechanics is constructed in two different ways. The first approach makes use of the action-angle variables in the angular sector. The second scheme relies upon integrability of the system in the sense of Liouville.Comment: V2: presentation improved, new material and references added; the version to appear in JHE

Impact of D0-D0bar mixing on the experimental determination of gamma

Several methods have been devised to measure the weak phase gamma using decays of the type B+- --> D K+-, where it is assumed that there is no mixing in the D0-D0bar system. However, when using these methods to uncover new physics, one must entertain the real possibility that the measurements are affected by new physics effects in the D0-D0bar system. We show that even values of x_D and/or y_D around 10^{-2} can have a significant impact in the measurement of sin^2{gamma}. We discuss the errors incurred in neglecting this effect, how the effect can be checked, and how to include it in the analysis.Comment: 18 pages, Latex with epsfig, 8 figure

Improved Methods for Observing CP Violation in B+/- --> K+/- D0 and Measuring the CKM Phase gamma

Various methods are discussed for obtaining the CKM angle gamma through the interference of the charged B-meson decay channels B- -> K- D0 and B- -> K- D0-bar where the D0 and D0-bar decay to common final states. It is found that choosing final states which are not CP eigenstates can lead to large direct CP violation which can give significant bounds on gamma without any theoretical assumptions. If two or more modes are studied, gamma may be extracted with a precision on the order of +/-15 degrees given about 10^8 B-mesons. We also discuss the case of three body decays of the D0 where additional information may be obtained from the distribution of the D0 decay products and consider the impact of D-D-bar oscillations.Comment: 51 pages 8 figures, typo in equation 33 correcte

Detecting new physics contributions to the D0-D0bar mixing through their effects on B decays

New physics effects may yield a detectable mass difference in the D0-D0bar system, Delta m_D. Here we show that this has an important impact on some B --> D decays. The effect involves a new source of CP violation, which arises from the interference between the phases in the B --> D decays and those in the D0-D0bar system. This interference is naturally large. New physics may well manifest itself through Delta m_D contributions to these B decays.Comment: 10 pages, Revtex, no figures. To appear in PR

Order-of-magnitude speedup for steady states and traveling waves via Stokes preconditioning in Channelflow and Openpipeflow

Steady states and traveling waves play a fundamental role in understanding hydrodynamic problems. Even when unstable, these states provide the bifurcation-theoretic explanation for the origin of the observed states. In turbulent wall-bounded shear flows, these states have been hypothesized to be saddle points organizing the trajectories within a chaotic attractor. These states must be computed with Newton's method or one of its generalizations, since time-integration cannot converge to unstable equilibria. The bottleneck is the solution of linear systems involving the Jacobian of the Navier-Stokes or Boussinesq equations. Originally such computations were carried out by constructing and directly inverting the Jacobian, but this is unfeasible for the matrices arising from three-dimensional hydrodynamic configurations in large domains. A popular method is to seek states that are invariant under numerical time integration. Surprisingly, equilibria may also be found by seeking flows that are invariant under a single very large Backwards-Euler Forwards-Euler timestep. We show that this method, called Stokes preconditioning, is 10 to 50 times faster at computing steady states in plane Couette flow and traveling waves in pipe flow. Moreover, it can be carried out using Channelflow (by Gibson) and Openpipeflow (by Willis) without any changes to these popular spectral codes. We explain the convergence rate as a function of the integration period and Reynolds number by computing the full spectra of the operators corresponding to the Jacobians of both methods.Comment: in Computational Modelling of Bifurcations and Instabilities in Fluid Dynamics, ed. Alexander Gelfgat (Springer, 2018

Multiple extraordinary optical transmission peaks from evanescent coupling in perforated metal plates surrounded by dielectrics

© 2010 Optical Society of America. One print or electronic copy may be made for personal use only. Systematic reproduction and distribution, duplication of any material in this paper for a fee or for commercial purposes, or modifications of the content of this paper are prohibitedWe study numerically and theoretically the optical transmission of nanostructured gold films embedded in dielectric claddings. We show how multiple transmission peaks appear as the claddings thickness increases. These transmission peaks come not only from surface plasmon polariton excitations but also from the excitation of Fabry-Perot modes sustained at the claddings, coupled through the metal, as long as a periodic pattern is milled in the metal film. We propose that this structure could be used as an ultracompact all-optical switch by surrounding the metal film with Kerr nonlinear dielectric layers. (C) 2010 Optical Society of AmericaWe thank the FCT (Fundacao para a Ciencia e Tecnologia) for funding of this research through the projects SFRH/BD/8278/2002 and PTDC/FIS/68419/2006.Ortuño Molinero, R.; García Meca, C.; Rodríguez Fortuño, FJ.; Martí Sendra, J.; Martínez Abietar, AJ. (2010). Multiple extraordinary optical transmission peaks from evanescent coupling in perforated metal plates surrounded by dielectrics. Optics Express. 18(8):7893-7898. https://doi.org/10.1364/OE.18.007893S78937898188Dragila, R., Luther-Davies, B., & Vukovic, S. (1985). High Transparency of Classically Opaque Metallic Films. Physical Review Letters, 55(10), 1117-1120. doi:10.1103/physrevlett.55.1117Ebbesen, T. W., Lezec, H. J., Ghaemi, H. F., Thio, T., & Wolff, P. A. (1998). Extraordinary optical transmission through sub-wavelength hole arrays. Nature, 391(6668), 667-669. doi:10.1038/35570Koerkamp, K. J. K., Enoch, S., Segerink, F. B., van Hulst, N. F., & Kuipers, L. (2004). Strong Influence of Hole Shape on Extraordinary Transmission through Periodic Arrays of Subwavelength Holes. Physical Review Letters, 92(18). doi:10.1103/physrevlett.92.183901Takakura, Y. (2001). Optical Resonance in a Narrow Slit in a Thick Metallic Screen. Physical Review Letters, 86(24), 5601-5603. doi:10.1103/physrevlett.86.5601Zhou, L., Wen, W., Chan, C. T., & Sheng, P. (2005). Electromagnetic-Wave Tunneling Through Negative-Permittivity Media with High Magnetic Fields. Physical Review Letters, 94(24). doi:10.1103/physrevlett.94.243905Lomakin, V., & Michielssen, E. (2005). Enhanced transmission through metallic plates perforated by arrays of subwavelength holes and sandwiched between dielectric slabs. Physical Review B, 71(23). doi:10.1103/physrevb.71.235117Rakić, A. D., Djurišić, A. B., Elazar, J. M., & Majewski, M. L. (1998). Optical properties of metallic films for vertical-cavity optoelectronic devices. Applied Optics, 37(22), 5271. doi:10.1364/ao.37.005271Genet, C., & Ebbesen, T. W. (2007). Light in tiny holes. Nature, 445(7123), 39-46. doi:10.1038/nature05350Ghaemi, H. F., Thio, T., Grupp, D. E., Ebbesen, T. W., & Lezec, H. J. (1998). Surface plasmons enhance optical transmission through subwavelength holes. Physical Review B, 58(11), 6779-6782. doi:10.1103/physrevb.58.6779Martínez, A., & Martí, J. (2005). Negative refraction in two-dimensional photonic crystals: Role of lattice orientation and interface termination. Physical Review B, 71(23). doi:10.1103/physrevb.71.235115Ruan, Z., & Qiu, M. (2006). Enhanced Transmission through Periodic Arrays of Subwavelength Holes: The Role of Localized Waveguide Resonances. Physical Review Letters, 96(23). doi:10.1103/physrevlett.96.233901Economou, E. N. (1969). Surface Plasmons in Thin Films. Physical Review, 182(2), 539-554. doi:10.1103/physrev.182.539Esembeson, B., Scimeca, M. L., Michinobu, T., Diederich, F., & Biaggio, I. (2008). A High-Optical Quality Supramolecular Assembly for Third-Order Integrated Nonlinear Optics. Advanced Materials, 20(23), 4584-4587. doi:10.1002/adma.200801552Spano, R., Daldosso, N., Cazzanelli, M., Ferraioli, L., Tartara, L., Yu, J., … Pavesi, L. (2009). Bound electronic and free carrier nonlinearities in Silicon nanocrystals at 1550nm. Optics Express, 17(5), 3941. doi:10.1364/oe.17.003941Dani, K. M., Ku, Z., Upadhya, P. C., Prasankumar, R. P., Brueck, S. R. J., & Taylor, A. J. (2009). Subpicosecond Optical Switching with a Negative Index Metamaterial. Nano Letters, 9(10), 3565-3569. doi:10.1021/nl901764

Rabdomiosarcoma paratesticular: reporte de caso y revisión de la literatura

Objetivo: Ofrecer un alcance de la relevancia del diagnóstico oportuno del cáncer testicular, a partir de un caso infrecuente de rabdomiosarcoma paratesticular en un adulto. Reporte de Caso: Se trata de un paciente varón de 39 años, que ingresa al servicio de cirugía - urología por un aumento de volumen de contenido escrotal, de forma progresiva desde hace 2 años, con crecimiento paulatino de la masa. En la ecografía testicular se evidencia un notorio aumento de volumen de bolsas escrotales por aparente tumoración o masa de consistencia dura, de estructura heterogénea y aspecto sólido de bordes mal definidos. Considerando los hallazgos clínicos, marcadores testiculares e imagenológicos se diagnosticó un tumor paratesticular derecho. Se realizó una orquiectomía derecha más exéresis de tumor paratesticular derecho. Patología concluyó en rabdomiosarcoma embrionario paratesticular con cápsula rota. Paciente fue dado de alta con seguimiento por consulta externa y referido a hospital oncológico de cuarto nivel

Estimating the Power of Indirect Comparisons: A Simulation Study

Indirect comparisons are becoming increasingly popular for evaluating medical treatments that have not been compared head-to-head in randomized clinical trials (RCTs). While indirect methods have grown in popularity and acceptance, little is known about the fragility of confidence interval estimations and hypothesis testing relying on this method.We present the findings of a simulation study that examined the fragility of indirect confidence interval estimation and hypothesis testing relying on the adjusted indirect method.Our results suggest that, for the settings considered in this study, indirect confidence interval estimation suffers from under-coverage while indirect hypothesis testing suffers from low power in the presence of moderate to large between-study heterogeneity. In addition, the risk of overestimation is large when the indirect comparison of interest relies on just one trial for one of the two direct comparisons.Indirect comparisons typically suffer from low power. The risk of imprecision is increased when comparisons are unbalanced