Subspace hypercyclicity

A bounded linear operator T on Hilbert space is subspace-hypercyclic for a subspace M if there exists a vector whose orbit under T intersects the subspace in a relatively dense set. We construct examples to show that subspace-hypercyclicity is interesting, including a nontrivial subspace-hypercyclic operator that is not hypercyclic. There is a Kitai-like criterion that implies subspace-hypercyclicity and although the spectrum of a subspace-hypercyclic operator must intersect the unit circle, not every component of the spectrum will do so. We show that, like hypercyclicity, subspace-hypercyclicity is a strictly infinite-dimensional phenomenon. Additionally, compact or hyponormal operators can never be subspace-hypercyclic.Comment: 15 page

Chaotic differential operators

We give sufficient conditions for chaos of (differential) operators on Hilbert spaces of entire functions. To this aim we establish conditions on the coefficients of a polynomial P(z) such that P(B) is chaotic on the space lp, where B is the backward shift operator. © 2011 Springer-Verlag.This work was partially supported by the MEC and FEDER Projects MTM2007-64222, MTM2010-14909, and by GVA Project GV/2010/091, and by UPV Project PAID-06-09-2932. The authors would like to thank A. Peris for helpful comments and ideas that produced a great improvement of the paper's presentation. We also thank the referees for their helpful comments and for reporting to us a gap in Theorem 1.Conejero Casares, JA.; Martínez Jiménez, F. (2011). Chaotic differential operators. Revista- Real Academia de Ciencias Exactas Fisicas Y Naturales Serie a Matematicas. 105(2):423-431. https://doi.org/10.1007/s13398-011-0026-6S4234311052Bayart, F., Matheron, É.: Dynamics of Linear Operators, Cambridge Tracts in Mathematics, vol. 179. Cambridge University Press, Cambridge (2009)Bermúdez T., Miller V.G.: On operators T such that f(T) is hypercyclic. Integr. Equ. Oper. Theory 37(3), 332–340 (2000)Bonet J., Martínez-Giménez F., Peris A.: Linear chaos on Fréchet spaces. Int. J. Bifur. Chaos Appl. Sci. Eng. 13(7), 1649–1655 (2003)Chan K.C., Shapiro J.H.: The cyclic behavior of translation operators on Hilbert spaces of entire functions. Indiana Univ. Math. J. 40(4), 1421–1449 (1991)Conejero J.A., Müller V.: On the universality of multipliers on $${\mathcal{H}({\mathbb {C}})}$$ . J. Approx. Theory. 162(5), 1025–1032 (2010)deLaubenfels R., Emamirad H.: Chaos for functions of discrete and continuous weighted shift operators. Ergodic Theory Dyn. Syst. 21(5), 1411–1427 (2001)Devaney, R.L.: An introduction to chaotic dynamical systems, 2nd edn. In: Addison-Wesley Studies in Nonlinearity. Addison-Wesley Publishing Company Advanced Book Program, Redwood City (1989)Godefroy G., Shapiro J.H.: Operators with dense, invariant, cyclic vector manifolds. J. Funct. Anal. 98(2), 229–269 (1991)Grosse-Erdmann K.-G.: Hypercyclic and chaotic weighted shifts. Stud. Math. 139(1), 47–68 (2000)Grosse-Erdmann, K.-G., Peris, A.,: Linear chaos. Universitext, Springer, New York (to appear, 2011)Herzog G., Schmoeger C.: On operators T such that f(T) is hypercyclic. Stud. Math. 108(3), 209–216 (1994)Kahane, J.-P.: Some random series of functions, 2nd edn. In: Cambridge Studies in Advanced Mathematics, vol. 5. Cambridge University Press, Cambridge (1985)Martínez-Giménez F., Peris A.: Chaos for backward shift operators. Int. J. Bifur. Chaos Appl. Sci. Eng. 12(8), 1703–1715 (2002)Martínez-Giménez F.: Chaos for power series of backward shift operators. Proc. Am. Math. Soc. 135, 1741–1752 (2007)Müller V.: On the Salas theorem and hypercyclicity of f(T). Integr. Equ. Oper. Theory 67(3), 439–448 (2010)Protopopescu V., Azmy Y.Y.: Topological chaos for a class of linear models. Math. Models Methods Appl. Sci. 2(1), 79–90 (1992)Rolewicz S.: On orbits of elements. Stud. Math. 32, 17–22 (1969)Salas H.N.: Hypercyclic weighted shifts. Trans. Am. Math. Soc. 347(3), 93–1004 (1995)Shapiro, J.H.: Simple connectivity and linear chaos. Rend. Circ. Mat. Palermo. (2) Suppl. 56, 27–48 (1998

Heterogeneous pipelined square-root Kalman Filter algorithm for the MMSE-OSIC problem

The final publication is available at Springer via http://dx.doi.org/10.1007/s11227-009-0354-x[EN] This paper describes a pipelined parallel algorithm for the MMSE-OSIC decoding procedure proposed in V-BLAST wireless MIMO systems, for heterogeneous networks of processors. It is based on a block version of the square-root Kalman Filter algorithm that was initially devised to solve the RLS problem. It has been parallelized in a pipelined way obtaining a good efficiency and scalability. The optimum load balancing for this parallel algorithm is dynamic, but we derive a static load balancing scheme with good performance. © 2009 Springer Science+Business Media, LLC.This work has been supported by the Generalitat Valenciana, project 20080811, by the Universidad Politecnica de Valencia, project 20080009, by the Conserjería de Educacion de la Región de Murcia (Fundacion Séneca, 08763/PI/08), and by the Ministerio de Ciencia e Innovacion (TIN2008-06570-C04-02).Martínez Zaldívar, FJ.; Vidal Maciá, AM.; Giménez Cánovas, D. (2011). Heterogeneous pipelined square-root Kalman Filter algorithm for the MMSE-OSIC problem. Journal of Supercomputing. 58(2):235-243. https://doi.org/10.1007/s11227-009-0354-xS235243582Foschini GJ (1996) Layered space-time architecture for wireless communications in a fading environment when using multiple antennas. Bell Labs Techn J 1:41–59Hassibi B (2000) An efficient square-root algorithm for BLAST. In: IEEE international conference on acoustics, speech and signal processing 2000, vol 2, pp II737–II740Zhu H, Lei Z, Chin FPS (2004) An improved square-root algorithm for BLAST. IEEE Signal Process Lett 11(9)Choi Y-S, Voltz PJ, Cassara FA (2001) On channel estimation and detection for multicarrier signals in fast and selective Rayleigh fading channels. IEEE Trans Commun 49(8)Burg A, Haene S, Perels D, Luethi P, Felber N, Fichtner W (2006) Algorithm and VLSI architecture for linear MMSE detection in MIMO-OFDM systems. In: Proceedings of the IEEE int symp on circuits and systems, May 2006Martínez Zaldívar FJ (2007) Algoritmos paralelos segmentados para los problemas de Mínimos Cuadrados Recursivos (RLS) y de Detección por Cancelación Ordenada y Sucesiva de Interferencia (OSIC). PhD thesis, Facultad de Informática, Universidad Politécnica de Valencia, SpainSayed AH, Kailath T (1994) A state-space approach to adaptive RLS filtering. IEEE Signal Process Mag 11(3):18–60Kumar V, Gram A, Gupta A, Karypis G (2003) An introduction to parallel computing: design and analysis of algorithms, Chap 4, 2nd edn. Addison-Wesley, Harlow

Efectos de una unidad didáctica de mimo basada en el modelo de Educación Deportiva sobre la interculturalidad

The aim of this study was to assess the impact of a Sport Education unit on elementary school students’ intercultural competence. The program involved the participation of 28 fifth-grade students (M = 10.75; DT = .75) from a state school in Region of Murcia, Spain.A quasi-experimental design, pretest and posttest (of quantitative and qualitative nature) measures, was used. The data included students’ questionnaires and interviews, andteachers’ interviews and diary notes. Results indicated that students improved on positive emotional responses, as well as providing help and having better relations with their peers from different cultures/countries. The incidence of methodological elements, communication and the social climate of the classroom on the development of intercultural competence is also discussed. Lines of future research are suggested in order to improve the model for the development of intercultural competence.El propósito de este estudio fue conocer el impacto generado por una unidad didáctica de mimo basada en el Modelo de Educación Deportiva (MED) sobre la competencia intercultural del alumnado de primaria. Participaron 28 estudiantes (M = 10.75; DT = .75) de quinto curso de educación primaria pertenecientes a un colegio ubicado en la Región de Murcia (España). Se desarrolló un diseño cuasiexperimental con medidas pretest y postest, de naturaleza cuantitativa y cualitativa. La información fue recabada mediante cuestionarios y entrevistas al alumnado, así como diarios y entrevistas a los docentes. Los resultados mostraron mejoras en la respuesta emocional positiva, así como en la ayuda, y las relaciones entre iguales de distintas culturas y países. Se discute también la incidencia de los elementos metodológicos, la comunicación y el clima social del aula sobre el desarrollo de la competencia intercultural. Se sugieren líneas de investigación futura al objeto de perfeccionar el modelo para el desarrollo de la competencia intercultural.

Influence of ocular biometric factors on the defocus curve in an enlarged depth-of-focus intraocular lens

Background: To assess the influence of biometric measurements on the defocus curve after the implantation of enlarged depth-of-focus (EDoF) intraocular lens (IOL). Methods: Patients who underwent cataract surgery with bilateral implantation of Tecnis Symfony IOL were enrolled. Preoperatively, axial length (AL), corneal keratometry (K), pupil size and corneal aberrations were measured. 1 month after surgery, distance, intermediate, and near visual acuities (VA) were recorded. At 3 months, monocular and binocular corrected contrast sensitivities under photopic and mesopic lighting conditions were measured with CSV-1000E test. At 6-months, the defocus curve between −5.00 to + 3.00 diopters (D) was assessed in steps of 0.50 D, and NEI-RQL-42 questionnaire was administered. Results: One hundred thirty one eyes of 66 patients were included. Binocular logMAR VA better than 0.1 for intermediate vision was obtained in 90% of patients, whereas only 17.7% obtained that result in near vision. The rate of satisfaction was high (96%) and most of them (85.5%) had no or little difficulties in near vision. The mean amplitude of the defocus curve was 2.35D ± 0.73D, and smaller AL, smaller pupils, younger age, and male sex were associated with wider range of clear vision. Conclusions: Tecnis Symfony IOL enables functional vision at all distances, but demographic variables and preoperative biometric measurements like AL and pupil size influence the postoperative amplitude of the defocus curve. These parameters could be used to predict the performance of EDoF IOLs

Distributional chaos for operators with full scrambled sets

In this article we answer in the negative the question of whether hypercyclicity is sufficient for distributional chaos for a continuous linear operator (we even prove that the mixing property does not suffice). Moreover, we show that an extremal situation is possible: There are (hypercyclic and non-hypercyclic) operators such that the whole space consists, except zero, of distributionally irregular vectors.The research of first and third author was supported by MEC and FEDER, project MTM2010-14909 and by GV, Project PROMETEO/2008/101. The research of second author was supported by the Marie Curie European Reintegration Grant of the European Commission under grant agreement no. PERG08-GA-2010-272297. The financial support of these institutions is hereby gratefully acknowledged. We also want to thank X. Barrachina for pointing out to us a gap in the proof of a previous version of Theorem 3.1.Martínez Jiménez, F.; Oprocha, P.; Peris Manguillot, A. (2013). Distributional chaos for operators with full scrambled sets. Mathematische Zeitschrift. 274(1-2):603-612. https://doi.org/10.1007/s00209-012-1087-8S6036122741-2Banks, J., Brooks, J., Cairns, G., Davis, G., Stacey, P.: On Devaney’s definition of chaos. Am. Math. Monthly 99(4), 332–334 (1992)Barrachina, X., Peris, A.: Distributionally chaotic translation semigroups. J. Differ. Equ. Appl. 18, 751–761 (2012)Beauzamy, B.: Introduction to Operator Theory and Invariant Subspaces. North-Holland, Amsterdam (1988)Bermúdez, T., Bonilla, A., Martínez-Giménez, F., Peris, A.: Li–Yorke and distributionally chaotic operators. J. Math. Anal. Appl. 373, 83–93 (2011)Bayart, F., Matheron, E.: Dynamics of linear operators, vol. 179. Cambridge University Press, London(2009).Costakis, G., Sambarino, M.: Topologically mixing hypercyclic operators. Proc. Am. Math. Soc. 132, 385–389 (2004)Devaney, R.L.: An introduction to chaotic dynamical systems, 2nd edn. Addison-Wesley Studies in Nonlinearity. Addison-Wesley Publishing Company Advanced Book Program. Redwood City (1989)Feldman, N.: Hypercyclicity and supercyclicity for invertible bilateral weighted shifts. Proc. Am. Math. Soc. 131, 479–485 (2003)Grosse-Erdmann, K.-G.: Hypercyclic and chaotic weighted shifts. Studia Math. 139(1), 47–68 (2000)Grosse-Erdmann, K.-G., Peris Manguillot, A.: Linear Chaos. Universitext, Springer, London (2011)Hou, B., Cui, P., Cao, Y.: Chaos for Cowen-Douglas operators. Proc. Am. Math. Soc 138, 929–936 (2010)Hou, B., Tian, G., Shi, L.: Some dynamical properties for linear operators. Ill. J. Math. 53, 857–864 (2009)Li, T.Y., Yorke, J.A.: Period three implies chaos. Am. Math. Monthly 82(10), 985–992 (1975)Martínez-Giménez, F., Oprocha, P., Peris, A.: Distributional chaos for backward shifts. J. Math. Anal. Appl. 351, 607–615 (2009)Müller, V., Peris, A.: A Problem of Beauzamy on Irregular Operators (2011). (Preprint)Oprocha, P.: Distributional chaos revisited. Trans. Am. Math. Soc. 361, 4901–4925 (2009)Oprocha, P.: A quantum harmonic oscillator and strong chaos. J. Phys. A 39(47), 14559–14565 (2006)Schweizer, B., Smítal, J.: Measures of chaos and a spectral decomposition of dynamical systems on the interval. Trans. Am. Math. Soc. 344(2), 737–754 (1994)Wu, X., Zhu, P.: The principal measure of a quantum harmonic oscillator. J. Phys. A 44(505101), 6 (2011

RepA-WH1 prionoid: Clues from bacteria on factors governing phase transitions in amyloidogenesis

10 p.-1 fig.In bacterial plasmids, Rep proteins initiate DNA replication by undergoing a structural transformation coupled to dimer dissociation. Amyloidogenesis of the ‘winged-helix’ N-terminal domain of RepA (WH1) is triggered in vitro upon binding to plasmid-specific DNA sequences, and occurs at the bacterial nucleoid in vivo. Amyloid fibers are made of distorted RepA-WH1 monomers that assemble as single or double intertwined tubular protofilaments. RepA-WH1 causes in E. coli an amyloid proteinopathy, which is transmissible from mother to daughter cells, but not infectious, and enables conformational imprinting in vitro and in vivo; i.e. RepA-WH1 is a ‘prionoid’. Microfluidics allow the assessment of the intracellular dynamics of RepA-WH1: bacterial lineages maintain two types (strains-like) of RepA-WH1 amyloids, either multiple compact cytotoxic particles or a single aggregate with the appearance of a fluidized hydrogel that it is mildly detrimental to growth. The Hsp70 chaperone DnaK governs the phase transition between both types of RepA-WH1 aggregates in vivo, thus modulating the vertical propagation of the prionoid. Engineering chimeras between the Sup35p/[PSI*] prion and RepA-WH1 generates [REP-PSI*], a synthetic prion exhibiting strong and weak phenotypic variants in yeast. These recent findings on a synthetic, self-contained bacterial prionoid illuminate central issues of protein amyloidogenesis.Research on RepA-WH1 amyloids at CIBCSIC is currently financed by Spanish MINECO grants BIO2012-30852 and CSD2009-00088.Peer reviewe

El modelo de Educación Deportiva y la orientación. Efectos en la satisfacción con la vida, las inteligencias múltiples, las necesidades psicológicas básicas y las percepciones sobre el modelo de los adolescentes

The aim of this study was to assess the effects of a Sport Education (SE) model-based teaching unit through orienteering on grade 9 (14-17 years) students’ life satisfaction, multiple intelligences, basic psychological needs and curricular model perceptions.81 students (Mage = 14.62; SD = .80) allocated in three intact groups from a high-school in Region of Murcia (Spain), took part in this unit. Based on a quasi-experimental design (pretest-posttest measures), data were collected from interviews (teacher perspective) and both quantitative and qualitative questionnaires (student perspective). Significant improvements were obtained on the development of the three main SE goals (competency, literacy and enthusiasm), whereas no significant changes were found on life satisfaction and multiple intelligences. Findings confirmed orienteering as a suitable content to be taught according through the pedagogical principles of SE model.Likewise, results showed its benefits on the development of the objectives this pursues.Se examinaron los efectos de una unidad didáctica de orientación deportiva (OD) basada en el modelo de Educación Deportiva (ED) sobre la satisfacción con la vida, las inteligencias múltiples, las necesidades psicológicas básicas y las percepciones del modelo en estudiantesde tercer curso de educación secundaria. La muestra estuvo comprendida por 81 estudiantes (M de edad = 14.62; DT = .80) distribuidos en tres grupos naturales, pertenecientes a un instituto ubicado en la Región de Murcia (España). A partir de un diseño cuasi-experimental (medidas pretest-postest), se recabaron datos mediante entrevistas (percepción docente), cuestionarios cuantitativos y cualitativos (percepción discente). Se obtuvieronmejoras significativas en el desarrollo de los tres objetivos que persigue el modelo (competencia, cultura deportiva y entusiasmo), al tiempo queno se revelaron cambios significativos en la satisfacción con la vida y en las inteligencias múltiples. Los resultados constatan a la OD como contenido apto para ser abordado mediante los principios del modelo de ED y respaldansu eficaciarespecto a los objetivos que este últimopersigue

Variabilidad radiológica de la artroplastia de cadera, según la dominancia del cirujano

El objetivo de este trabajo es analizar la relación entre la dominancia de los cirujanos ortopédicos y el correcto posicionamiento del componente acetabular en las artroplastias totales de cadera. Secundariamente, se analiza la posible relación entre esta dominancia del cirujano y la lateralidad del procedimiento quirúrgico a realizar ya sean caderas derechas o izquierdas. Para ello, se crearon 2 grupos. El grupo A correspondiente a 20 caderas intervenidas por un cirujano de dominancia diestra y el grupo B formado por 20 intervenciones realizadas por otro cirujano de dominancia zurda Las mediciones se realizaron sobre la proyección radiográfica AP de pelvis del control postquirúrgico usando el visor de rayos del hospital. Para la valoración de la anteversión se utilizó el método descrito por Widmer. Con este trabajo hemos demostrado una mayor dificultad para la correcta implantación del cotilo por parte de nuestro cirujano zurdo en el caso de intervenir caderas izquierdas