A Verilog HDL digital architecture for delay calculation

A method for the calculation of the delay between two digital signals with central frequencies in the range [20, 300] Hz is presented. The method performs a delay calculation in order to determine the bearing angle of a sound source. Computing accuracy is tested against a previous implementation of the Cross Correlation Derivative method. A Verilog RTL model of the method has been tested on a Xilinx® FPGA in order to evaluate the real performance of the method. Simulations of an ASIC design on a standard CMOS technology predict a power saving of about 25 times per delay stage over previous implementations.Fil: Chacón-Rodríguez, A.. Universidad de Mar del Plata. Laboratorio de Componentes Electrónicos; ArgentinaFil: Martín-Pirchio, F. N.. Universidad Nacional del Sur. Departamento de Ingeniería Eléctrica y de Computadoras; ArgentinaFil: Julian, Pedro Marcelo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Investigaciones en Ingeniería Eléctrica "Alfredo Desages". Universidad Nacional del Sur. Departamento de Ingeniería Eléctrica y de Computadoras. Instituto de Investigaciones en Ingeniería Eléctrica "Alfredo Desages"; ArgentinaFil: Mandolesi, Pablo Sergio. Universidad Nacional del Sur. Departamento de Ingeniería Eléctrica y de Computadoras; Argentin

Transfer Hydrogenation of Azo Compounds with Ammonia Borane Using a Simple Acyclic Phosphite Precatalyst

Tris(quinolin-8-yl)phosphite, P(Oquin)(3), promotes the dehydrogenation of H3N center dot BH3 (AB) and the transfer hydrogenation of azoarenes using ammonia borane (AB) as H-2 source. The metal-free reduction of azoarenes proceeds under mild reaction conditions upon which several diphenylhydrazine derivatives are obtained in high yields. The reactivity of P(Oquin)(3) toward AB was evaluated through NMR in situ tests. The rate of the reaction, activation parameters, deuterium kinetic isotope effect (DKIE) and linear-free energy relationship were investigated. Such mechanistic and kinetic studies suggest that P(Oquin)(3) is a precatalyst and that AB is likely involved in more than one stage of the reaction pathway. Furthermore, the kinetic data indicate that the reaction proceeds through an ordered transition state, possibly associative

Análisis y validación de algoritmos de separación de fuentes sonoras para aplicaciones en entornos industriales

Este documento presenta la evaluación del costo computacional de las operaciones matemáticas básicas de tres algoritmos de separación de fuentes sonoras: FastlCA, adaptativo basado en gradiente natural y adaptativo EASI basado en gradiente relativo. Estos algoritmos fueron seleccionados por su relativa simplicidad y la viabilidad de implementación en hardware de bajo costo en aplicaciones de localización acústica de agentes móviles en entornos industriales

Testing the Effect of Sodium Bicarbonate Base on Blood Lactate Levels after a Strenuous Exercise

INTRODUCTION: The lactate is an intermediate metabolic, its production in the skeletal muscle increase during the exercise, principally in anaerobic condition that include oxygen deficiency in the skeletal muscle during the exercise. The lactate is released to systemic blood, where it participate in the Cori cycle, although in the blood, the metabolite can modify the blood’s pH. For the last condition, the human has some mechanism to attenuate the lactate effects on the pH in blood PURPOSE: The purpose of this study was evaluate the effect of the sodium bicarbonate ingestion on the lactate blood levels before and after an acute strenuous exercise in undergraduate students. METHODS: Five male (21.2 ± 21.5 years; 78 ± 9.73 kg) were recruited. Two strenuous exercise test of 4 minutes were performed. An interval of 24 hours was present between exercise sessions. The test consisted in intervals of 30 seconds to maximum intensity and with periods of submaximal intensity for 30 seconds. The lower intensity consisted of continuous aerobic activity to ≈ 60% of HRmax. The first test was performed without NaHCO3 ingestion. Contrary, the second exercise session was performed with NaHCO3 ingestion (300mg/kg body weight). The NaHCO3 ingestion was performed 2 hours previous to exercise. RESULTS: Without sodium bicarbonate ingestion, the lactate before physical effort was 1,74mmol, SD 2,15mmol, the lactate after to physical effort was 7,94mmol, SD 9,73, the oxygen in blood before to physical effort was 99% SD 0%, the oxygen after to physical effort was 96,6% SD 1,74%, the systolic blood pressure before physical effort was 122mmHg, SD 11,66mmHg, the diastolic blood pressure was 91,2 mmHg, SD 10mmHg, after physical effort the systolic blood pressure was 131,2mmHg. SD 11,90mmHg, the diastolic blood pressure was 76mmHg, SD 12,58mmHg. With sodium bicarbonate ingest, the lactate before physical effort was 0.4mmol, SD 0.56mmol, lactate after physical effort was 6.73, SD 7,31mmol, the oxygen in blood before physical effort was 99% SD 0%, after to physical effort was 96.66%, SD 0.47%. CONCLUSION: The present study shows that the bicarbonate ingestion does not change significantly the blood lactate concentrations after a strenuous exercise. Our current data could be consequence by the low sample size. Therefore, we suggest perform a new study with a bigger sample than the current work

Perforación colónica por endoprótesis biliar impactada

Introducción. La colocación de endoprótesis biliares es cada día más frecuente por ser actualmente una de las mejores opciones para el tratamiento de patologías de la vía biliar. La migración de las endoprótesis es una de las complicaciones que puede ocurrir en hasta un 10,8 % de los pacientes, pero en muy raras ocasiones llegan a causar una perforación intestinal. Caso clínico. Se trata de una paciente de 61 años, a quien cinco años atrás se le realizó una colangiopancreatografía retrógrada endoscópica por coledocolitiasis. Consultó por presentar dolor abdominal, y al examen físico se encontraron abdomen agudo y plastrón en fosa ilíaca izquierda a la palpación. La tomografía computarizada informó un cuerpo extraño a nivel del colon descendente, con perforación del mismo. Se realizó laparotomía exploratoria y colostomía por perforación del colon sigmoides secundaria a prótesis biliar migrada. Resultados. La paciente evolucionó favorablemente y a los seis meses se realizó el cierre de la colostomía, sin complicaciones. Conclusión. Los pacientes a quienes se les colocan prótesis biliares requieren un seguimiento adecuado para evitar complicaciones que, aunque raras, pueden ocurrir, como la migración intestinal con perforación. El tratamiento de dichas complicaciones se hace por vía endoscópica, laparoscópica o laparotomía en caso de complicación severa

Effect of dilute sulfuric acid pretreatment on the physicochemical properties and enzymatic hydrolysis of coffee cut-stems

Coffee-cut stems are a potential fermentable sugars source, which can be upgraded in different value-added products and energy vectors. Nevertheless, there are few reports focused on the acid pretreatment and saccharification processes. Thus, this paper evaluates the effect of the acid pretreatment and saccharification conditions of coffee cut-stems to find the highest sugar yield. Thereafter, the influence of the residence time in the acid pretreatment and the -glucosidase supplementation in the saccharification process were analyzed. The combined severity factor and crystallinity index were used as metrics to evaluate both processes. In all assays, an increase in the crystallinity index was observed. Furthermore, a nonlinear trend of the combined severity factor respect to the residence time in the acid pretreatment was evidenced. The highest sugar yield was 66.75% with a combined severity factor of 1.84. The better saccharification process was achieved at combined severity factor of 2.01 with a digestibility of 43%. The addition of -glucosidase in the enzymatic hydrolysis allows increasing the value to 69.07%. Hence, low temperatures, acid concentrations, and the -glucosidase supplementation allows obtaining a high sugar yield from coffee cut stems.The authors express their gratitude for the financial support to the Programme of ERASMUS + - International Credit Mobility celebrated between the Universidad Nacional de Colombia at Manizales and the University of Minho. The COLCIENCIAS program “Jóvenes Investigadores e Innovadores, Convocatoria 761 de 2016”, the international collaboration project COLCIENCIAS – CONICYT with code PCCI140052, HERMES code 23567 (23876) entitled “Análisis Tecno-económico y Ambiental de Biorefinerías a partir de Residuos Lignocelulósicos con Esquemas de Recirculación de Microorganismos”, the research program entitled “Reconstrucción del tejido social en zonas posconflicto en Colombia” SIGP code: 57579 with the project entitled “Competencias empresariales y de innovación para el desarrollo económico y la inclusión productiva de las regiones afectadas por el conflicto colombiano” SIGP code 58907. Contract number: FP44842-213-2018.info:eu-repo/semantics/publishedVersio