Diet of Hyphessobrycon auca (Pisces, characidae) in Iberá Wetland (Northeastern, Argentina)

Hyphessobrycon auca Almirón, Casciotta, Bechara & Ruiz Díaz, 2004, inhabit small lakes located at the northwest of Iberá wetland in Argentina. This research describes sorne aspects of its feeding. Samples were collected from its type locality from 2007 to 2009. Analysis of 70 digestive tracts of individuals ranging from 24 to 56 mm standard length (SL) showed that higher plants, algae, and quironomids larvae dominated the diet in terms of relative volume and occurrence frequency. Therefore, this species was characterized as omnivorous, but there was a growing trend towards herbivory when size class incremed. Smaller size class (< 35 mm SL) fed on higher proportion of animal preys such as quironomids larvae and protozoans, in contrast to larger ones who consumed almost exclusively plants and algae

Complexity of Instances for Combinatorial Optimization Problems

Non

LSSVM APLICADA EN LA ESTIMACIÓN DE LA RESISTENCIA DE ROTOR EN MOTOR DE INDUCCIÓN JAULA DE ARDILLA

En este artículo se estima la resistencia de rotor presente en la dinámica de un motor de inducción Jaula de Ardilla aplicando LSSVM en regresión. El problema es que la resistencia de rotor es difícil de medir por lo que se requiere estimarla. Además, de ser afectada por el incremento en la temperatura, conllevando a que la constante de tiempo del rotor cambie y afecte los parámetros del motor. Se plantea un modelo del motor, en Simulink de Matlab, del cual se extrae la data, se preprocesa y se aplica el algoritmo LSSVM en regresión con Kernel no lineal RBF y la optimización de gamma se hace por validación cruzada. La medición del desempeño del modelo se utilizó la raíz cuadrada del error medio de predicción. Obteniendo buenos resultados

NUEVOS MODELOS NANOTECNOLÓGICOS EN EL DISEÑO DE PIEL ARTIFICIAL CON NANOPARTÍCULAS PARA EL RECUBRIMIENTO DE PRÓTESIS DE MANO Y PIERNA EN DISCAPACITADOS

El artículo trata sobre la investigación y el desarrollo de una nueva metodología el desarrollo de modelos nanotecnológicos de acuerdo a una metodología de diseño, implementación de recubrimientos y mantenimiento, para la captura, transformación, almacenamiento y extracción de datos, de la piel artificial con nanopartículas para el recubrimiento de prótesis; equipándolo con un sistema de adquisición de datos que tome las señales de su par biológico y luego sean replicadas en la prótesis usando técnicas de inteligencia artificial

A substituted sulfonamide and its Co (II), Cu (II), and Zn (II) complexes as potential antifungal agents

A sulfonamide 1-tosyl-1-H-benzo(d)imidazol-2-amine (TBZA) and three new complexes of Co(II), Cu(II), and Zn(II) have been synthesized. The compounds have been characterized by elemental analyses, FTIR, 1H, and 13C-NMR spectroscopy. The structure of the TBZA, and its Co(II) and Cu(II) complexes, was determined by X-ray diffraction methods. TBZA and its Co(II) complex crystallize in the triclinic P-1 space group, while the Cu(II) complex crystallizes in the monoclinic P21/c space group. Antifungal activity was screened against eight pathogenic yeasts: Candida albicans (DMic 972576), Candida krusei (DMic 951705), Candida glabrata (DMic 982882), Candida tropicalis (DMic 982884), Candida dubliniensis (DMic 93695), Candida guilliermondii (DMic 021150), Cryptococcus neoformans (ATCC 24067), and Cryptococcus gattii (ATCC MYA-4561). Results on the inhibition of various human (h) CAs, hCA I, II, IV, VII, IX, and XII, and pathogenic beta and gamma CAs are also reported.Facultad de Ciencias ExactasInstituto de Física La PlataCentro de Química Inorgánic

High-resolution optical imaging of the core of the globular cluster M15 with FastCam

We present high-resolution I-band imaging of the core of the globular cluster M15 obtained at the 2.5 m Nordic Optical Telescope with FastCam, a low readout noise L3CCD based instrument. Short exposure times (30 ms) were used to record 200000 images (512 x 512 pixels each) over a period of 2 hours 43 min. The lucky imaging technique was then applied to generate a final image of the cluster centre with FWHM ~ 0".1 and 13" x 13" FoV. We obtained a catalogue of objects in this region with a limiting magnitude of I=19.5. I-band photometry and astrometry are reported for 1181 stars. This is the deepest I-band observation of the M15 core at this spatial resolution. Simulations show that crowding is limiting the completeness of the catalogue. At shorter wavelengths, a similar number of objects has been reported using HST/WFPC observations of the same field. The cross-match with the available HST catalogues allowed us to produce colour-magnitude diagrams where we identify new Blue Straggler star candidates and previously known stars of this class.Comment: 11 pages, 15 figures. Accepted for publication in Monthly Notices of the Royal Astronomical Societ

Low-Q whispering gallery modes in anisotropic metamterials shells

Anisotropic and inhomogeneous metamaterial shells are studied in order to exploit all their resonant mode richness. These multilayer structures are based on a cylindrical distribution of radially dependent constitutive parameters including an inner void cavity. Shell, cavity, and whispering gallery modes are characterized, and special attention is paid to the latter ones. The whispering gallery modes are created at the boundary layers of the shell with the background. Energy localization is produced with highly radiative characteristics when the localization takes place at the external layer. These low-Q resonant states have frequencies that are independent of the shell thickness. However, their quality factors can be controlled by the number of layers forming the shell, which allows confining electromagnetic waves at the interface layers (internal or external), and make them suitable for the harvesting of electromagnetic energy.The authors acknowledge the financial support of Spanish Ministry MINECO (Grants No. TEC 2010-19751 and No. Consolider CSD2008-00066), and the US Office of Naval Research (USA). J. Sanchez-Dehesa acknowledges useful discussions with Federico Sabina and Matthew Guild.Diaz Rubio, A.; Carbonell Olivares, J.; Torrent Martí, D.; Sánchez-Dehesa Moreno-Cid, J. (2013). Low-Q whispering gallery modes in anisotropic metamterials shells. Physical Review B. 88(11):115118-115128. doi:10.1103/PhysRevB.88.115118S1151181151288811Williams, C. R., Andrews, S. R., Maier, S. A., Fernández-Domínguez, A. I., Martín-Moreno, L., & García-Vidal, F. J. (2008). Highly confined guiding of terahertz surface plasmon polaritons on structured metal surfaces. Nature Photonics, 2(3), 175-179. doi:10.1038/nphoton.2007.301Watts, C. M., Liu, X., & Padilla, W. J. (2012). Metamaterial Electromagnetic Wave Absorbers. Advanced Materials, 24(23), OP98-OP120. doi:10.1002/adma.201200674Spinelli, P., Verschuuren, M. A., & Polman, A. (2012). Broadband omnidirectional antireflection coating based on subwavelength surface Mie resonators. Nature Communications, 3(1). doi:10.1038/ncomms1691Munk, B. A. (2000). Frequency Selective Surfaces. doi:10.1002/0471723770Carbonell, J., Lheurette, E., & Lippens, D. (2011). FROM REJECTION TO TRANSMISSION WITH STACKED ARRAYS OF SPLIT RING RESONATORS. Progress In Electromagnetics Research, 112, 215-224. doi:10.2528/pier10121402Wang, S., Garet, F., Blary, K., Croënne, C., Lheurette, E., Coutaz, J.-L., & Lippens, D. (2010). Composite left/right-handed stacked hole arrays at submillimeter wavelengths. Journal of Applied Physics, 107(7), 074510. doi:10.1063/1.3374703Aznabet, M., Navarro-Cia, M., Kuznetsov, S. A., Gelfand, A. V., Fedorinina, N. I., Goncharov, Y. G., … Sorolla, M. (2008). Polypropylene-substrate-based SRR- and CSRR- metasurfaces for submillimeter waves. Optics Express, 16(22), 18312. doi:10.1364/oe.16.018312Barnes, W. L., Dereux, A., & Ebbesen, T. W. (2003). Surface plasmon subwavelength optics. Nature, 424(6950), 824-830. doi:10.1038/nature01937Pendry, J. B. (2004). Mimicking Surface Plasmons with Structured Surfaces. Science, 305(5685), 847-848. doi:10.1126/science.1098999Torrent, D., & Sánchez-Dehesa, J. (2009). Radial Wave Crystals: Radially Periodic Structures from Anisotropic Metamaterials for Engineering Acoustic or Electromagnetic Waves. Physical Review Letters, 103(6). doi:10.1103/physrevlett.103.064301Carbonell, J., Díaz-Rubio, A., Torrent, D., Cervera, F., Kirleis, M. A., Piqué, A., & Sánchez-Dehesa, J. (2012). Radial Photonic Crystal for detection of frequency and position of radiation sources. Scientific Reports, 2(1). doi:10.1038/srep00558Horiuchi, N., Segawa, Y., Nozokido, T., Mizuno, K., & Miyazaki, H. (2005). High-transmission waveguide with a small radius of curvature at a bend fabricated by use of a circular photonic crystal. Optics Letters, 30(9), 973. doi:10.1364/ol.30.000973Lee, P.-T., Lu, T.-W., Fan, J.-H., & Tsai, F.-M. (2007). High quality factor microcavity lasers realized by circular photonic crystal with isotropic photonic band gap effect. Applied Physics Letters, 90(15), 151125. doi:10.1063/1.2724899Carbonell, J., Torrent, D., & Sanchez-Dehesa, J. (2013). Radial Photonic Crystal Shells and Their Application as Resonant and Radiating Elements. IEEE Transactions on Antennas and Propagation, 61(2), 755-767. doi:10.1109/tap.2012.2225015Harrington, R. F. (2001). Time-Harmonic Electromagnetic Fields. doi:10.1109/9780470546710Vinogradov, A. P., Dorofeenko, A. V., Erokhin, S. G., Inoue, M., Lisyansky, A. A., Merzlikin, A. M., & Granovsky, A. B. (2006). Surface state peculiarities in one-dimensional photonic crystal interfaces. Physical Review B, 74(4). doi:10.1103/physrevb.74.045128Goto, T., Baryshev, A. V., Inoue, M., Dorofeenko, A. V., Merzlikin, A. M., Vinogradov, A. P., … Granovsky, A. B. (2009). Tailoring surfaces of one-dimensional magnetophotonic crystals: Optical Tamm state and Faraday rotation. Physical Review B, 79(12). doi:10.1103/physrevb.79.125103Carbonell, J., Torrent, D., Díaz-Rubio, A., & Sánchez-Dehesa, J. (2011). Multidisciplinary approach to cylindrical anisotropic metamaterials. New Journal of Physics, 13(10), 103034. doi:10.1088/1367-2630/13/10/103034Torrent, D., & Sánchez-Dehesa, J. (2010). Acoustic resonances in two-dimensional radial sonic crystal shells. New Journal of Physics, 12(7), 073034. doi:10.1088/1367-2630/12/7/073034Yao, Y., Yao, J., Narasimhan, V. K., Ruan, Z., Xie, C., Fan, S., & Cui, Y. (2012). Broadband light management using low-Q whispering gallery modes in spherical nanoshells. Nature Communications, 3(1). doi:10.1038/ncomms1664Navau, C., Prat-Camps, J., & Sanchez, A. (2012). Magnetic Energy Harvesting and Concentration at a Distance by Transformation Optics. Physical Review Letters, 109(26). doi:10.1103/physrevlett.109.263903Carbonell, J., Cervera, F., Sánchez-Dehesa, J., Arriaga, J., Gumen, L., & Krokhin, A. (2010). Homogenization of two-dimensional anisotropic dissipative photonic crystal. Applied Physics Letters, 97(23), 231122. doi:10.1063/1.352638