The complexity of a dynamical system exhibiting a homoclinic orbit is given by its dynamical core which, due to Cantwell, Conlon and Fenley, is a set uniquely determined in the isotopy class, up to a ...topological conjugacy, of the end-periodic map relative to that orbit. In this work we prove that a sufficient condition to determine the dynamical core of a homoclinic orbit of a Smale diffeomorphism on the
-disk is the non-existence of bigons relative to this orbit. Moreover, we propose a pruning method for eliminating bigons that can be used to find a Smale map without bigons and hence for finding the dynamical core.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
The existence of a homoclinic orbit in dynamical systems implies chaotic behaviour with positive entropy. In this work, we determine explicitly the Markov shifts associated to certain Smale horseshoe ...homoclinic orbits which allow us to compute a lower bound for the topological entropy that such a system can have. It is done associating a heteroclinic orbit which belongs to the same isotopy class and then determining the Markov partition of the dynamical core of an end periodic mapping.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
In this note we explain how to find the minimal topological chaos relative to finite set of homoclinic and periodic orbits. The main tool is the pruning method, which is used for finding a hyperbolic ...map, obtained uncrossing pieces of the invariant manifolds, whose basic set contains all orbits forced by the finite set under consideration. Then we will show applications related to transport phenomena and to the problem of determining the orbits structure coexisting with a finite number of periodic orbits arising from the bouncing ball model.
•The pruning method can be applied to certain physical models.•The combinatorics of the pruning map is found uncrossing invariant manifolds.•Infinite pruning regions are related to singularities without rotation.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
The Pruning Front Conjecture is proved for an open set of Hénon parameters far from unimodal. More specifically, for an open subset of Hénon parameter space, consisting of two connected components ...one of which intersects the area-preserving locus, it is shown that the associated Hénon maps are prunings of the horseshoe. In particular, their dynamics is a subshift of the two-sided two-shift.
La educacion es parte integrante de las nuevas tecnologias y eso es tan asi que un número cada vez mayor de universidades en todo el mundo esta exigiendo la alfabetizacion electronica como uno de los ...requisitos en sus examenes de acceso y de graduacion, por considerar que es un objetivo esencial preparar a los futuros profesionales para la era digital en los centros de trabajo. La Fundacion Nacional para la Ciencia(NSF), por medio del Sociedad Internacional para la Tecnologia en la Educacion (ISTE) y la Asociacion de profesores de informatica(CSTA), impulsa activamente un nuevo enfoque de ensenanza que permite visualizar los problemas de forma que sus posibles soluciones pueden ser representadas con secuencias de instrucciones y atravez de algoritmos, proponiendo que en todos los niveles de educacion y no solamente en las areas de informatica , se incluya el Pensamiento Computacional (Computational Thinking). Este nuevo enfoque educativo complementa los distintos modelos educativos ya que hace uso del pensamiento logico al hacer uso de las matematicas para interactuar con el mundo real, permitiendo que con el uso de dispositvos informaticos se puedan crear simulaciones en mundos virtuales en diferentes areas del conocimiento. Es asi que como parte de la metodologia de pensamiento computacional se encuentra la utilizacion de software de simulacion como apoyo para el aprendizaje y solucion de problemas, dichos paquetes informaticos permiten explorar, analizar, comprender, correlacionar y experimentar en el mundo virtual soluciones que posteriormente pueden aplicarse para resolver un problema real, como en el caso de la electronica en el diseno y programacion de circuitos., cuyos contenidos curriculares pueden ser complejos y extensos debido a la gran cantidad de desarrollos e innovaciones que han surgido en las últimas décadas.
Transforming growth factor (TGF) β1, β2, and β3 (TGF-β1–TGF-β3, respectively) are small secreted signaling proteins that each signal through the TGF-β type I and type II receptors (TβRI and TβRII, ...respectively). However, TGF-β2, which is well-known to bind TβRII several hundred-fold more weakly than TGF-β1 and TGF-β3, has an additional requirement for betaglycan, a membrane-anchored nonsignaling receptor. Betaglycan has two domains that bind TGF-β2 at independent sites, but how it binds TGF-β2 to potentiate TβRII binding and how the complex with TGF-β, TβRII, and betaglycan undergoes the transition to the signaling complex with TGF-β, TβRII, and TβRI are not understood. To investigate the mechanism, the binding of the TGF-βs to the betaglycan extracellular domain, as well as its two independent binding domains, either directly or in combination with the TβRI and TβRII ectodomains, was studied using surface plasmon resonance, isothermal titration calorimetry, and size-exclusion chromatography. These studies show that betaglycan binds TGF-β homodimers with a 1:1 stoichiometry in a manner that allows one molecule of TβRII to bind. These studies further show that betaglycan modestly potentiates the binding of TβRII and must be displaced to allow TβRI to bind. These findings suggest that betaglycan functions to bind and concentrate TGF-β2 on the cell surface and thus promote the binding of TβRII by both membrane-localization effects and allostery. These studies further suggest that the transition to the signaling complex is mediated by the recruitment of TβRI, which simultaneously displaces betaglycan and stabilizes the bound TβRII by direct receptor–receptor contact.
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IJS, KILJ, NUK, PNG, UL, UM
A strategy for cancer treatment was implemented, based on chemo-photodynamic therapy, utilizing a novel formulation, low-cost system called Cas-ZnONPs. This system consisted of the incorporation of ...Casiopeina III-ia (CasIII-ia), a hydrophilic copper coordination compound with well-documented anti-neoplastic activity, on Zinc oxide nanoparticles (ZnONPs) with apoptotic activity and lipophilicity, allowing them to permeate biological barriers. Additionally, ZnONPs exhibited fluorescence, with emission at different wavelengths depending on their agglomeration and enabling real-time tracking biodistribution. Also, ZnONPs served as a sensitizer, generating reactive oxygen species (ROS) in situ. In in vitro studies on HeLa and MDA-MB-231 cell lines, a synergistic effect was observed with the impregnated CasIII-ia on ZnONPs. The anticancer activity had an increase in cellular inhibition, depending on the dose of exposure to UV–vis irradiation. In in vivo studies utilized zebrafish models for xenotransplanting stained MDA-MB-231 cells and testing the effectiveness of Cas-ZnONPs treatment. The treatment successfully eliminated cancer cells, both when combined with Photodynamic Therapy (PDT) and when used alone. However, a significantly higher concentration (50 times) of Cas-ZnONPs was required in the absence of PDT. This demonstrates the potential of Cas-ZnONPs in cancer treatment, especially when combined with PDT.
A new nanoformulation that works as a theranostic system, Cas-ZnONPs has emission at different wavelengths and presents two different synergistic effects, between its components: ZnO nanoparticles and Casiopeina III-ia, and an additional one in the presence of PDT. The anticancer activity was studied in zebrafish, achieving the elimination of xenotransplanted MDA-MB-231 cells. Display omitted
•Zinc oxide nanoparticles as carriers for an inorganic antineoplastic, Casiopeina III-ia.•Real-time bioimaging studies through ZnO fluorescence at different wavelengths.•Synergetic anticancer activity between ZnO nanoparticles and Casiopeina III-ia.•A second synergistic anticancer activity with Cas-ZnONPs and photodynamic therapy.•In zebrafish the theranostic compound eliminated xenotransplanted cancer cells.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
In this paper we deal with the Boyland forcing of horseshoe orbits. We prove that there exists a set R of renormalizable horseshoe orbits containing only quasi-one-dimensional orbits, that is, for ...these orbits the Boyland order coincides with the unimodal order.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Transforming growth factor (TGF)‐βs are dimeric polypeptides that have vital roles in regulating cell growth and differentiation. They signal by assembling a receptor heterotetramer composed of two ...TβRI:TβRII heterodimers. To investigate whether the two heterodimers bind and signal autonomously, one of the TGF‐β protomers was substituted to block receptor binding. The substituted dimer, TGF‐β3 WD, bound the TβRII extracellular domain and recruited the TβRI with affinities indistinguishable from TGF‐β3, but with one‐half the stoichiometry. TGF‐β3 WD was further shown to retain one‐quarter to one‐half the signalling activity of TGF‐β3 in three established assays for TGF‐β function. Single‐molecule fluorescence imaging with GFP‐tagged receptors demonstrated a measurable increase in the proportion of TβRI and TβRII dimers upon treatment with TGF‐β3, but not with TGF‐β3 WD. These results provide evidence that the two TβRI:TβRII heterodimers bind and signal in an autonomous manner. They further underscore how the TGF‐βs diverged from the bone morphogenetic proteins, the ancestral ligands of the TGF‐β superfamily that signal through a RI:RII:RII heterotrimer.
In this study, Andrew Hinck and colleagues differentiate TGF‐β from BMP receptor complexes. Based on various biochemical techniques they report a functional hetero‐dimeric TGF‐β complex that contrasts the hetero‐tetrameric composition of active BMP receptors.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
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