162 research outputs found

    Intermittency reinjection probability density function with and without noise effects.

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    Intermittency phenomenon is a continuous route from regular to chaotic behaviour. Intermittency is an occurrence of a signal that alternates chaotic bursts between quasi-regular periods called laminar phases, driven by the so called reinjection probability density function (RPD). In this paper is introduced a new technique to obtain the RPD for type-II and III intermittency. The new RPD is more general than the classical one and includes the classical RPD as a particular case. The probabilities of the laminar length, the average laminar lengths and the characteristic relations are determined with and without lower bound of the reinjection in agreement with numerical simulations. Finally, it is analyzed the noise effect in intermittency. A method to obtain the noisy RPD is developed extending the procedure used in the noiseless case. The analytical results show a good agreement with numerical simulations

    Theory of intermittency applied to classical pathological cases

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    The classical theory of intermittency developed for return maps assumes uniform density of points reinjected from the chaotic to laminar region. Though it works fine in some model systems, there exist a number of so-called pathological cases characterized by a significant deviation of main characteristics from the values predicted on the basis of the uniform distribution. Recently, we reported on how the reinjection probability density (RPD) can be generalized. Here, we extend this methodology and apply it to different dynamical systems exhibiting anomalous type-II and type-III intermittencies. Estimation of the universal RPD is based on fitting a linear function to experimental data and requires no a priori knowledge on the dynamical model behind. We provide special fitting procedure that enables robust estimation of the RPD from relatively short data sets (dozens of points). Thus, the method is applicable for a wide variety of data sets including numerical simulations and real-life experiments. Estimated RPD enables analytic evaluation of the length of the laminar phase of intermittent behaviors. We show that the method copes well with dynamical systems exhibiting significantly different statistics reported in the literature. We also derive and classify characteristic relations between the mean laminar length and main controlling parameter in perfect agreement with data provided by numerical simulation

    Analysis of the type V intermittency using the Perron-Frobenius Operator

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    A methodology to study the reinjection process in type V intermittency is introduced. The reinjection probability density function (RPD), and the probability density of the laminar lengths (RPDL) for type V intermittency are calculated. A family of maps with discontinuous and continuous RPD functions is analyzed. Several tests were performed, in which the proposed technique was compared with the classical theory of intermittency, the M function methodology, and numerical data. The analysis exposed that the new technique can accurately capture the numerical data. Therefore, the scheme presented herein is a useful tool to theoretically evaluate the statistical variables for type V intermittency.Fil: Elaskar, Sergio Amado. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Estudios Avanzados en Ingeniería y Tecnología. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto de Estudios Avanzados en Ingeniería y Tecnología; Argentina. Universidad Nacional de Córdoba; ArgentinaFil: del Rio, Gaston Ezequiel. Universidad Politécnica de Madrid; España. Escuela Tecnica Superior de Ingenieros Aeronauticos, Madrid; EspañaFil: Schulz, Walkiria. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Departamento de Aeronáutica; Argentina. Comisión Nacional de Actividades Espaciales. Instituto de Altos Estudios Espaciales "Mario Gulich"; Argentin

    Studies for Type-I, type-II and Type-III Intermittencies.

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    There are several topics in fluid mechanics where the intermittency phenomenon appears, such as in Lorenz systems, Rayleigh-Bénard convection, DNLS equation and turbulence. The correct evaluation of the intermittency phenomenon contributes to a better prediction and a proper description of these topics. We summarized here a new method we have recently proposed to evaluate the reinjection probability function for type-II and type-III intermittencies. The new reinjection probability density (RPD) has been observed in the broad class of maps, as we have checked by both numerical simulations and analytical studies. For type-II and type-III intermittencies, we presented a new one-parameter family of functions describing the reinjection probability, being the usual type-II uniform reinjection probability a particular case of our RPD. For the type-III case, a new two-parameter family of RPD has been found from which one can derive the lower bound of reinjection (LBR). By extending the preceding analysis of type-II and type-III intermittencies, we give here a new RPD for the type-I case, from which we also derive the densities of the laminar phase lengths and the new characteristic relations

    G4.5 Pamam Dendrimer-Risperidone: Biodistribution and Behavioral Changes in In Vivo Model

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    Dendritic polymers are considered as emerging and outstanding carriers as modern medicinal systems due to their derivatisable branched architecture and possibility to modify them in numerous ways. Here, G4.5 PAMAM dendrimers were obtained as carriers of the antipsychotic drug risperidone. Despite their extensive applicability in the pharmaceutical field, the use of dendrimers as carriers in biological systems is constrained due to their inherent associated toxicity. The biocompatibility of dendrimers and dendrimer-risperidone complexes was evaluated in vivo for biological performance. To this end, the pharmacokinetics and biodistribution after oral treatment of free risperidone and dendrimer-risperidone complexes were studied in healthy mice. Also, the behavioral changes such as locomotion, aggression, dominance in male and female mice were evaluated both after a single dose and after daily therapy for 8 days. Also, in vivo effects of risperidone and dendrimer-risperidone complexes on the locomotion of zebrafish larvae were explored. The data obtained suggest that the unmetabolized risperidone complexes increase the arrival to the brain after 90 minutes. On the other hand, behavioral studies showed an increase in the potency of the drug in animals treated with the complexesFil: Prieto, Maria Jimena. Universidad Nacional de Quilmes. Departamento de Ciencia y Tecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto Multidisciplinario de Biología Celular. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Instituto Multidisciplinario de Biología Celular. Universidad Nacional de La Plata. Instituto Multidisciplinario de Biología Celular; ArgentinaFil: del Rio Zabala, Nahuel Eduardo. Universidad Nacional de Quilmes. Departamento de Ciencia y Tecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto Multidisciplinario de Biología Celular. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Instituto Multidisciplinario de Biología Celular. Universidad Nacional de La Plata. Instituto Multidisciplinario de Biología Celular; ArgentinaFil: Marotta, Cristian Hernán. Universidad Nacional de Quilmes. Departamento de Ciencia y Tecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto Multidisciplinario de Biología Celular. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Instituto Multidisciplinario de Biología Celular. Universidad Nacional de La Plata. Instituto Multidisciplinario de Biología Celular; ArgentinaFil: Bichara, Darío Román. Fundación Instituto Leloir; ArgentinaFil: Simonetta, Sergio Hernan. Fundación Instituto Leloir; ArgentinaFil: Chiaramoni, Nadia Silvia. Universidad Nacional de Quilmes. Departamento de Ciencia y Tecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto Multidisciplinario de Biología Celular. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Instituto Multidisciplinario de Biología Celular. Universidad Nacional de La Plata. Instituto Multidisciplinario de Biología Celular; ArgentinaFil: Alonso, Silvia del Valle. Universidad Nacional de Quilmes. Departamento de Ciencia y Tecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto Multidisciplinario de Biología Celular. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Instituto Multidisciplinario de Biología Celular. Universidad Nacional de La Plata. Instituto Multidisciplinario de Biología Celular; Argentin

    Some characteristics of the M function methodology to describe the reinjection process in chaotic intermittency

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    The M function methodology allows calculating the statistical properties of intermittency in a broad class of one-dimensional maps. It has shown to be very accurate in type I, II, III and V intermittencies; and it also includes the uniform reinjection as a particular case. This paper studies some properties of the M function methodology. We establish the conditions that a reinjection probability density function must verify to obtain and we describe new pathological cases where the reinjection is not uniform, but the characteristic relation is the same that for uniform reinjection.Fil: Elaskar, Sergio Amado. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Estudios Avanzados en Ingeniería y Tecnología. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto de Estudios Avanzados en Ingeniería y Tecnología; ArgentinaFil: del Rio, Ezequiel(EXT). Universidad Politécnica de Madrid; EspañaFil: Gutierrez Marcantoni, Luis Felipe. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Departamento de Aeronáutica; Argentin

    Noise influence on the Characteristic Relations and Reinjection Probability Densities of type-II and type-III Intermittencies

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    This paper explores the effect of the noise in the reinjection probability densities (RPD) for type-II and type-III intermittencies by using the temporal series of iterative maps. The RPD are calculated by means of a new method proposed in Refs. [1] and [2] and the results are compared with both, numerical simulations and analytical calculations. In addition, we provide an explanation for the gap observed in early experiments around the unstable point in the Poincaré map. We show that and added white noise approaches the RPD to the case of uniform reinjection for small distances of iterations to the unstable point. For large distances the RPD should be incremented with respect to the noiseless case. These numerical results suggest the existence of a noise induced reinjection mechanis

    Microalgae-bacterial biomass outperforms PN-anammox biomass for oxygen saving in continuous-flow granular reactors facing extremely low-strength freshwater aquaculture streams

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    The dissolved oxygen (DO) concentration in water streams is one of the most important and critical quality parameters in aquaculture farms. The main objective of this study was to evaluate the potential of two Continuous Flow Granular Reactors, one based on Partial Nitrification-Anammox biomass (Aquammox CFGR) and the other on Microalgae-Bacteria biomass (AquaMab CFGR), for improving dissolved oxygen availability in the recirculation aquaculture systems (RAS). Both reactors treated the extremely low-strength effluents from a freshwater trout farm (1.39 mg NH4 +-N/L and 7.7 mg TOC/L). The Aquammox CFGR, removed up to 68% and 100% of ammonium and nitrite, respectively, but the DO concentration in the effluent was below 1 mg O2/L while the anammox activity was not maintained. In the AquaMab CFGR, bioaugmentation of aerobic granules with microalgae was attained, producing an effluent with DO concentrations up to 9 mg O2/L and removed up to 77% and 80% of ammonium and nitrite, respectively, which is expected to reduce the aeration costs in fish farms.info:eu-repo/semantics/publishedVersio

    The Relationship between Squat Jump Performance and Sprint Profile in Collegiate Track and Field Athletes

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    The squat jump (SJ) necessitates the inter-play of various biomechanical components for better jump performance. Good sprint performance requires the inter-play of many of the same biomechanical components. Researchers have previously examined how the speed, force, velocity, and power interact during sprinting, but have yet to examine how these measures are associated with SJ performance measures. PURPOSE: Examine the relationship between squat jump performance measures and the sprint profile measurements of collegiate track and field athletes. METHODS: Twenty-five athletes (18 males and 7 females) completed two squat jump trials with a linear encoder attached to a 45 lbs. bar placed on the athlete’s upper back. Measures of interest during the concentric phase of the SJ included jump height, maximum force, maximum velocity, maximum power, and rate of force development. Athletes then completed two 30-meter acceleration sprints. The MySprint mobile application was used to acquire the athlete’s sprint profile and to assess maximal theoretical horizontal force, maximal theoretical velocity, optimal velocity, maximal theoretical power, maximal speed, maximal ratio of force, force-velocity slope, and decrease in ratio of force. The best trial was used for statistical analysis. Pearson’s or Spearman’s correlation coefficients were conducted between SJ measures and sprint profile measures. RESULTS: There was a positive correlation between SJ height and maximal speed (r = 0.402; p = 0.042). Maximal power during the SJ was positively correlated with maximal speed (r = 0.476; p = 0.014); optimal velocity (r = 0.469; p = 0.018); maximal theoretical power (r = 0.462; p = 0.018); maximal theoretical velocity (r = 0.452; p = 0.021); theoretical horizontal force (r = 0.431; p = 0.028); and maximal ratio force (r = 0.428; p = 0.029). Maximal velocity during the SJ was correlated with maximal speed (r = 0.519; p = 0.007); maximal theoretical velocity (r = 0.499; p = 0.010); optimal velocity (r = 0.486; p = 0.014); and maximal theoretical power (r = 0.484; p = 0.012). No other correlations were significant. CONCLUSION: Maximal velocity and power during the concentric phase of the SJ are moderately to strongly correlated with maximal sprinting speed, velocity, and power. SJ height is positively correlated with maximum sprint speed. There is a lack of significant correlations between other measures of the SJ and sprint profile measures. SJ power and velocity are correlated with sprint performance, therefore power and velocity improved through plyometric SJ training may be transferable to achieve better sprint performance

    Long-term Engraftment of Single Genetically Modified Human Epidermal Holoclones Enables Safety Pre-assessment of Cutaneous Gene Therapy

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    Predicting the risks of permanent gene therapy approaches involving the use of integrative gene-targeting vectors has become a critical issue after the unfortunate episode of a clinical trial in children with X-linked severe combined immunodeficiency (X-SCID). Safety pre-assessment of single isolated gene-targeted stem cells or their derivative clones able to regenerate their tissue of origin would be a major asset in addressing untoward gene therapy effects in advance. Human epidermal stem cells, which have extensive proliferative potential in vitro, theoretically offer such a possibility as a method of assessment. By means of optimized organotypic culture and grafting methods, we demonstrate the long-term in vivo regenerative capacity of single gene-targeted human epidermal stem cell clones (holoclones). Both histopathological analysis of holoclone-derived grafts in immunodeficient mice and retroviral insertion site mapping performed in the holoclone in vitro and after grafting provide proof of the feasibility of pre-assessing genotoxicity risks in isolated stem cells before transplantation into patients. Our results provide an experimental basis for previously untested assumptions about the in vivo behavior of epidermal stem cells prospectively isolated in vitro and pave the way for a safer approach to cutaneous gene therapy
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