Interconvertible forms of muscle phosphorylase phosphatase

Fil:Chelala, C.A. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina.Fil:Torres, H.N. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina

Regulation of skeletal muscle phosphorylase phosphatase activity. I. Kinetic properties of the active and inactive forms

1. 1. The inactivation of phosphorylase a phosphatase decreased the maximum velocity of the phosphorylase a to phosphorylase b conversion reaction when it was assayed at different phosphorylase a concectrations. 2. 2. Maximal phosphorylase a phosphatase activities were found between pH 8 and 8.3. Inactivation of the phosphorylase a phosphatase led to a decrease in the activity in all the pH ranges tested. 3. 3. Theophylline and caffeine stimulated the phosphorylase a phosphatase. The effect of these substances was exerted in the reaction assay of the enzyme. 4. 4. ATP, ADP, AMP, GTP, UTP, CTP and pyrophosphate were found to decrease the rate of the reaction catalyzed by phosphorylase a phosphatase. This effect showed a striking parallelism with the capacity of these compounds to stimulate the phosphatase inactivation. © 1970.Fil:Torres, H.N. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina.Fil:Chelala, C.A. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina

Regulation of skeletal muscle phosphorylase phosphatase activity. II. Interconversions

1. 1. The incubation of the pegion breast muscle homogenate at 37° resulted in a time-dependent decrease in phosphatase activity. This effect was stimulated by ATP, ADP, AMP, GTP, UTP, CTP or pyrophosphate. 2. 2. Reactivation of an inactive phosphorylase a phosphatase preparation was obtained by incubation with ATP-Mg2+. Phosphocreatine-Mg2+ or Mg2+ were also found to be effective in bringing about the reactivation of the enzyme. 3. 3. 3′,5′-Cyclic AMP decreased the yield of the active enzyme when it was added either at the beginning or during the activation reaction. © 1970.Fil:Chelala, C.A. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina.Fil:Torres, H.N. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina

Challenges of a College Tutor

AbstractThis paper explains the changes that have emerged in recent years in Europe and Latin America about the universities, and therefore the challenges teachers are faced with, in order to become good tutors. The tutor's challenges are divided into pedagogical, social, administrative, and technical. The conclusion from reviewing the literature is that there are five main challenges for the tutors, which have to do with the mastery of his subject, creating a learning atmosphere, knowing the administrative processes, having the knowledge for instructional design, and the most complex of all, the efficient use of Information and Communications Technology (ICT)

The use of public support on internationalization activities, firms competencies and internationalization requirements

In particularly in times of budget constraints governments should analyze in detail all aspects related to the implementation of their public support to enterprises. With an Heckman selection model and data collected through a survey to Portuguese firms, we test which variables may affect awareness and use of the public support to internationalization. The results show that firms’ competencies positively affect awareness and negatively affect use of public support. Otherwise, the requirements of internationalization positively affect both the awareness and the use of public support

Linefish resources annual report for the year 2000. Part 1: fisheries assessment

This work reflects the activities of line and trap fishing in Southern Mozambique in 2000. The catch in line fishing has been estimated at 441 mt, according to the DNAP records. The same sources indicated that 1767 days were spent at sea and the estimated catch rate was 250 Kg per boaticlay. Most of the line fishing effort shifted away from Maputo and moved to Inhambane region. The monthly analysis of fishing vessels, stricter controls over catch and effort data submission, development of long-term research programme and the continuation of the on board sampling to improve the data collection are the recommendation for line fishing. The catch of trap vessels increases from 30mt in 1997 to 172 mt in 2000, during which the total number of traps increased from 25 to 300. During this time the number of fishing days has remained relatively constant, as well the soak time. These data sets are thus not compatible with each other, reflecting an increase in daily catch from 243 Kg to 791 kg. The species composition is mainly dominated by P. coeruleopunctatus, C. puniceus, C. nufar and E. andersoni

Automatic learning for the system identification. A case study in the prediction of power generation in a wind farm

[EN] One of the greatest technical challenges of today is obtaining predictive models for complex systems. In this paper we propose using data collected during a process to identify said process by means of automatic learning algorithms. Specifically, we describe the development of a project to determine the predictive model of a system based on supervised automatic learning algorithms. As an example, we use the problem of determining the energy generated in a wind farm. We do so by studying how the data collected are transformed, the search for the best algorithm, how to determine its goodness, and finally, the training and adjustment of the selected model. This study relies on the Python programming language, which has libraries that facilitate this type of project, and the Jupyter Notebook environment to carry out the project and disseminate the results.[ES] Uno de los mayores desafíos tecnológicos de la actualidad es la obtención de modelos predictivos de sistemas complejos. En este artículo se propone darle valor a los datos recogidos sobre un proceso utilizándolos para la identificación del mismo mediante el empleo de algoritmos de aprendizaje automático. En concreto, se describe el desarrollo de un proyecto de determinación del modelo predictivo de un sistema, a partir de algoritmos de aprendizaje automático supervisado, usando como ejemplo el problema de determinar la generación de energía de un campo eólico. Para ello se estudian las transformaciones a realizar a los datos recogidos, la búsqueda del mejor algoritmo, cómo determinar la bondad del mismo y, finalmente, el entrenamiento y a juste del modelo seleccionado. Todo ello usando el lenguaje de programación Python, que dispone de librerías que facilitan este tipo de proyectos, y en el entorno de Jupyter Notebook para realiza el proyecto y divulgar los resultados.Este trabajo ha sido financiado por el Ministerio de Ciencia,Innovación y Universidades a través del proyecto titulado “Gestión de Redes Eléctricas Inteligentes con estimación De producción de Energías Renovables basado en modelos mesoescalaresde alta resolución - GRIDER”, RTC-2017-6409-3Aguilar, R.; Torres, J.; Martín, C. (2018). Aprendizaje Automático en la Identificación de Sistemas. Un Caso de Estudio en la Predicción de la Generación Eléctrica de un Parque Eólico. Revista Iberoamericana de Automática e Informática. 16(1):114-127. https://doi.org/10.4995/riai.2018.9421SWORD11412716

Patient reported outcome measure in atopic dermatitis patients treated with dupilumab: 52-weeks results

Dupilumab is used to treat atopic dermatitis (AD) patients who have proven to be refractory to previous treatments. The aim of this study was to assess evolution and patient reported outcome measures in adult patients with moderate-to-severe AD treated with dupilumab in routine clinical practice. The outcomes were evaluated and registered at baseline and weeks 16, 40 and 52. The variables evaluated were: disease severity, pruritus, stressful life events, difficulty to sleep, anxiety and depression, quality of life, satisfaction, adherence to the treatment, efficacy and safety. Eleven patients were recruited between 14 Nov 2017 and 16 Jan 2018. Demographic variables: 90% Caucasian, 82% women. Clinical variables: Mean duration of AD = 17.7 (±12.8), 91% had severe disease severity. At baseline, SCORAD median (range) score = 69.2 (34.8–89.2); itch was reported by 100% of patients; itch visual analogue scale median (range) was 9 (6–10); HADS median (range) total score = 13 (5–21); DLQI mean score = 16 (2–27); EQ-5D-3L median (range) = 57 (30–99). At week- 52 there was a significant reduction of SCORAD scores median (range) = 4.3 (0–17.1), HADS total score median (range) = 2 (0–10) and improved quality of life EQ-5D-3L median (range) = 89 (92–60). This study confirms that dupilumab, used for 52-weeks under routine clinical practice, maintains the improved atopic dermatitis signs and symptoms obtained at week 16, with a good safety profile. © 2021 by the authors. Licensee MDPI, Basel, Switzerland

Modeling and behavior of the simulation of electric propagation during deep brain stimulation

Deep brain stimulation (DBS) is an effective treatment for Parkinson's disease. In the literature, there are a wide variety of mathematical and computational models to describe electric propagation during DBS; however unfortunately, there is no clarity about the reasons that justify the use of a specific model. In this work, we present a detailed mathematical formulation of the DBS electric propagation that supports the use of a model based on the Laplace Equation. Moreover, we performed DBS simulations for several geometrical models of the brain in order to determine whether geometry size, shape and ground location influence electric stimulation prediction by using the Finite Element Method (FEM). Theoretical and experimental analysis show, firstly, that under the correct assumptions, the Laplace equation is a suitable alternative to describe the electric propagation, and secondly, that geometrical structure, size and grounding of the head volume affect the magnitude of the electric potential, particularly for monopolar stimulation. Results show that, for monopolar stimulation, basic and more realistic models can differ more than 2900%

A wavelet analysis of the Rosenblatt process: chaos expansion and estimation of the self-similarity parameter

By using chaos expansion into multiple stochastic integrals, we make a wavelet analysis of two self-similar stochastic processes: the fractional Brownian motion and the Rosenblatt process. We study the asymptotic behavior of the statistic based on the wavelet coefficients of these processes. Basically, when applied to a non-Gaussian process (such as the Rosenblatt process) this statistic satisfies a non-central limit theorem even when we increase the number of vanishing moments of the wavelet function. We apply our limit theorems to construct estimators for the self-similarity index and we illustrate our results by simulations