EIS, Mott Schottky and EFM analysis of the electrochemical stability and dielectric properties of Ca-P-Ag and Ca-P-Si-Ag coatings obtained by plasma electrolytic oxidation in Ti6Al4V

Ti6Al4V ELI (ASTM F136) alloy is one of the most used alloys in devices for osteosynthesis and joint replacement. However, the properties of this alloy can be improved regarding biocompatibility and the osteointegration with the bone tissue through coatings. The aim of this study was the evaluation of the electrochemical behavior of a coating obtained by plasma electrolytic oxidation on Ti6Al4V ELI, using electrolyte solutions enriched with PO4 2-, Ca+2, Si+4 ions and various concentrations of Ag+1. The coatings were characterized by electrochemical impedance spectroscopy (EIS) and Mott-Schottky (M-S) in a three-electrode cell with a simulated physiological solution. The electrochemical behavior was compared with electrostatic force microscopy (EFM). The EIS results showed improved stability properties in corrosion for Ca-P-Ag coatings, compared with Ca-P-Si-Ag. Nyquist and Bode Spectra showed relaxations related to charge transference to the double electrochemical layer and the reflex of the microstructural changes and conductivity of the coating given by its composition. According to with M-S results, all the samples showed an n-type conductivity increased with silver inclusion. The potential, the phase, and amplitude of the coatings with silver inclusion compared to uncoated Ti6Al4V were observed by EFM

Conceptual quality modelling and integrated control of combined urban drainage system

This paper presents the first results of conceptual quality modelling approach oriented to the integrated real-time control (RTC) strategy for urban drainage networks (UDN) and wastewater treatment plants (WWTP) developed in the European project LIFE EFFIDRAIN (Efficient Integrated Real-time Control in Urban Drainage and Wastewater Treatment Plants for Environmental Protection). Model predictive control (MPC) has been selected as a proper RTC to minimize the polluting discharge in case of raining events. The simulator SWMM5 was modified to integrate a lumped conceptual model for total suspended solids (TSS) called SWMM-TSS, which has been used as virtual reality for calibration and validation of the proposed modelling approaches in Perinot network, a real case study in Bordeaux.Peer ReviewedPostprint (author's final draft

La lúdica como estrategia de mejoramiento del proceso lector de los estudiantes de primero de Básica Primaria de la I. E. Fulgencio Lequerica Vélez

Aprender a leer es lo más importante que provee la escuela, ya que la lectura es un instrumento fundamental de instrucción en tanto ayuda a desarrollar las capacidades cognitivas y, en parte, el pensamiento. El proceso lector es, por tanto, cognitivo y lingüístico. En este proyecto se tendrá en cuenta la adquisición y desarrollo del proceso lector en los estudiantes de primero de educación Básica Primaria, de la I. E. FULGENCIO LEQUERICA VELEZ en 2017, quienes muestran pocos avances en su proceso, lo cual no les permite acceder a la comprensión y análisis de los contenidos Según la UNESCO (1997) esta problemática no es exclusiva del grupo estudiado, ya que una investigación realizada en Suramérica señala que, con excepción de Cuba, el nivel de logro de la región en lenguaje es considerablemente bajo. La mayoría de estudiantes realizan una comprensión fragmentaria de los textos que leen, reconocen las palabras de un texto, pero no consiguen determinar por qué se dice lo que se dice o para qué. Es decir, a los niños se les enseña a traducir las palabras escritas al lenguaje oral, pero sin entender ni interpretar el significado de lo que leen. Se aprende a leer un texto en voz alta o a pronunciarlo, pero no a aprender leyendo

Psychophysics-Based Electrode Selection for Cochlear Implant Listeners

<p>Cochlear implant listeners are presented with a time and frequency-quantized version of speech signals. In the frequency domain, resolution is limited by the number of electrodes in each listener's array. Current cochlear implant speech processing strategies implicitly assume that the information presented to each one of these electrodes is perceived as unique and independent. However, previous research suggests that stimuli presented on different electrodes can be indiscriminable (e.g. Zwolan et al., 1997; Throckmorton and Collins, 1999; Henry et al., 2000) . Additional studies suggest that stimuli presented on one electrode can influence the perception of stimuli on neighboring electrodes (e.g. Shannon, 1990; Chatterjee and Shannon, 1998; Boëx et al., 2003). Removing this redundant or occluded information could cause more distinct or perceivable information to be presented to the listener and possibly result in improved speech recognition.</p><p>Previous studies have used psychophysical data to identify the electrodes with the highest potential to confound speech recognition (Zwolan et al., 1997, Boëx et al., 2003, and Garadat et al., 2012). In order to minimize electrode interactions and maximize the amount of perceivable information, each of these studies used a single psychophysical metric to deactivate the electrodes across all time windows of the speech processing strategy. For some listeners, these reduced electrode sets resulted in improved speech recognition over using the of the electrodes in their array. These studies did not compare the results of using different psychophysical metrics to exclude electrodes for a group of listeners nor did they investigate speech recognition performance as a function of the number of electrodes excluded from the array.</p><p>In this work, three different psychophysical metrics were used to obtain a multidimensional estimate of the potential "usefulness'' of each electrode. These results were then used to inform two different methods of psychophysics-motivated electrode selection. The first method incorporated individual data into each listener's energy-driven speech processing strategy. For each time window, the electrodes with the highest energy that were also most likely to be perceived, according to the psychophysical data, were selected for stimulation. The second method sequentially excluded the electrodes with the highest potential to confound from the array across all time windows, resulting in a group of psychophysics-motivated electrode sets for each metric. Evaluating each of these electrode sets exhaustively would require a prohibitive amount of experimental time. To mitigate this problem, an adaptive procedure was developed to estimate performance as a function of cochlear implant parameters in a time-efficient manner. For each metric, the procedure estimated the set with the highest estimated probability of correct phoneme identification. Listeners' speech recognition performance using this electrode set was then compared to their performance using their full electrode array. For both electrode selection methods, listeners' speech recognition scores were generally comparable to those obtained in the clinical condition. This finding supports the hypothesis that listeners were not perceiving all the information presented to them using their clinical speech processing strategy and their complete set of electrodes. Additionally, these results suggest that improvements to the proposed electrode selection strategies should be in investigated in order to increase the amount of perceivable information presented to cochlear implant listeners.</p>Dissertatio

Adsorption of Aqueous Mercury(II)Species by Commercial Activated Carbon Fibres with and without Surface Modification

The adsorption of HgCl2, [HgCl4]2– and Hg2+ onto a series of activated carbon fibres was studied. These included the as-received commercial activated carbon fibre (K), that obtained after modification via by sulphuric acid oxidation (KAC) and that obtained after modification by reaction with pentaethylenehexamine (KBAS). The effects of concentration (10–1500 mg/l), solution pH (1–10) and temperature (25°C, 35°C and 45°C) were studied. The mercury(II) adsorption isotherms followed the Langmuir model with maximum adsorption capacities of 361.0, 142.2 and 300.3 mg/g for HgCl2, [HgCl4]2– and Hg2+, respectively. Fibre K proved to have the highest adsorption capacity towards HgCl2 but the best results for the adsorption of [HgCl4]2– and Hg2+ were obtained with the fibre KAC. The performance of fibre KBAS was always worse than those of the other two fibres tested. The negative values obtained for ΔH0 and ΔG0 indicate that the adsorption was an exothermic and spontaneous process and also demonstrated that the adsorption of Hg(II) is a feasible process

Telehealth Assessment of Frailty in Community Dwelling Older Adults using the Modified Physical Performance Test (Poster)

Frailty in Older Adults ● Frailty is a health condition that effects increasing numbers of the population past the age of 65 ● The modified Physical Performance Test (mPPT) is a test that assesses multiple dimensions of physical function with different levels of difficulty. It has been shown to assess frailty in an older adult population. ● Due to health care barriers, it may be advantageous to assess individuals via telehealth. ● It is critical to determine the concurrent validity of telehealth delivery of mPPT with that of a clinical setting to determine if it can increase access to car

Modulation of G(q)/PLC-mediated signaling by acute lithium exposure

© The Author(s), 2022. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Sanchez Trivino, C. A., Landinez, M. P., Duran, S., Gomez, M. del P., & Nasi, E. Modulation of G(q)/PLC-mediated signaling by acute lithium exposure. Frontiers in Cellular Neuroscience, 16, (2022): 838939, https://doi.org/10.3389/fncel.2022.838939.Although lithium has long been one of the most widely used pharmacological agents in psychiatry, its mechanisms of action at the cellular and molecular levels remain poorly understood. One of the targets of Li+ is the phosphoinositide pathway, but whereas the impact of Li+ on inositol lipid metabolism is well documented, information on physiological effects at the cellular level is lacking. We examined in two mammalian cell lines the effect of acute Li+ exposure on the mobilization of internal Ca2+ and phospholipase C (PLC)-dependent membrane conductances. We first corroborated by Western blots and immunofluorescence in HEK293 cells the presence of key signaling elements of a muscarinic PLC pathway (M1AchR, Gq, PLC-β1, and IP3Rs). Stimulation with carbachol evoked a dose-dependent mobilization of Ca, as determined with fluorescent indicators. This was due to release from internal stores and proved susceptible to the PLC antagonist U73122. Li+ exposure reproducibly potentiated the Ca response in a concentration-dependent manner extending to the low millimolar range. To broaden those observations to a neuronal context and probe potential Li modulation of electrical signaling, we next examined the cell line SHsy5y. We replicated the potentiating effects of Li on the mobilization of internal Ca, and, after characterizing the basic properties of the electrical response to cholinergic stimulation, we also demonstrated an equally robust upregulation of muscarinic membrane currents. Finally, by directly stimulating the signaling pathway at different links downstream of the receptor, the site of action of the observed Li effects could be narrowed down to the G protein and its interaction with PLC-β. These observations document a modulation of Gq/PLC/IP3-mediated signaling by acute exposure to lithium, reflected in distinct physiological changes in cellular responses.This work was supported by DIB-Universidad Nacional de Colombia, grant Hermes No. 41821

Contribution to Globularia phylogeny based on nuclear ribosomal spacer and two chloroplast DNA regions

Background and Purpose: Molecular approach has a major impact on phylogenetic studies of plants, considering that it gives useful information about evolutionary events and relations on all taxonomic levels. The sequence data of the nuclear ITS and of two chloroplast regions, trnL-trnF spacer and rbcL gene, obtained from thirteen Globularia L. taxa, including five Anatolian endemics, representing six sections altogether, were analyzed in order to determine the relations between the European and the Anatolian species and get a better insight into the phylogeny of several closely related Globularia taxa.  Materials and Methods: Total cellular DNA was extracted from fresh or frozen leaf tissue of thirteen Globularia samples. The ITS regions of nuclear DNA and two chloroplast DNA regions were amplified and sequenced. Obtained nuclear and combined plastid data matrices were subjected to Maximum Parsimony analyses. Results and Conclusions: Molecular data that were obtained in this study indicate the existence of separate centers of diversification for the European and the Anatolian Globularia. The results provide support for relationships among the studied Anatolian endemic species and indications for a redefinition of affinities of some of the European species. The results presented herein are discussed along with available morphological, karyological, phytogeographical and molecular data. Keywords: Globularia, ITS, trnL-trnF, rbcL, Maximum Parsimony, Quaternary</p