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The use of advanced modulation and control schemes for power converters, such as a Feedback Quantizer and Predictive Control, is widely studied in the literature. This work focuses on improving the closed-loop modulation scheme called Feedback Quantizer, which is applied to a three-phase voltage source inverter. This scheme has the natural behavior of mitigating harmonics at low frequencies, which are detrimental to electrical equipment such as transformers. This modulation scheme also provides good tracking for the voltage reference at the fundamental frequency. On the other hand, the disadvantage of this scheme is that it has a variable switching frequency, creating a harmonic spectrum in frequency dispersion, and it also needs a small sampling time to obtain good results. The proposed scheme to improve the modulation scheme is based on a Discrete Space Vector with virtual vectors to obtain a better approximation of the optimal vectors for use in the algorithm. The proposal improves the conventional scheme at a high sampling time (200 µs), obtaining a THD less than 2% in the load current, decreases the noise created by the conventional scheme, and provides a fixed switching frequency. Experimental tests demonstrate the correct operation of the proposed scheme.

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Pulsed electrolysis has become a promising research topic in recent decades due to advances in solid-state semiconductor devices. These technologies have enabled the design and construction of simpler, more efficient, and less costly high-voltage and high-frequency power converters. In this paper, we study high-voltage pulsed electrolysis considering variations in both power converter parameters and cell configuration. Experimental results are obtained for frequency variations ranging from 10 Hz to 1 MHz, voltage changes from 2 V to 500 V, and electrode separations from 0.1 to 2 mm. The results demonstrate that pulsed plasmolysis is a promising method for decomposing water for hydrogen production.

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BACKGROUND/OBJECTIVES: Little is known about the effect of serum amylase enzymatic activity on glucose metabolism. We investigated the association of serum amylase enzymatic activity with fasting plasma glucose, insulin resistance (IR), and the plasma glucose and insulin response to an oral starch test (OST) in Mexican children. METHODS: Anthropometric data, glucose and insulin levels, and the serum enzymatic activity of total (AMYt), salivary (AMY1), and pancreatic (AMY2) amylase were analysed in 764 children (Nnormal weight  = 427/Nobesity  = 337). After categorization into low (LA) and high (HA) AMYt, an OST with commercial white bread was performed in 39 children (Nnormal weight  = 17/Nobesity  = 22). RESULTS: A positive association between serum enzymatic activity of AMY2 and IR was observed in children with obesity (p = 0.018). Children with normal weight had lower plasma glucose and insulin response to OST than children with obesity (Pglucose  = 4.1 × 10-12 ; Pinsulin  = 2.1 × 10-15 ). Compared with the LA group, children with HA showed lower plasma glucose and insulin response to OST (Pglucose ≤ 0.040; Pinsulin ≤ 0.015). CONCLUSION: Our results suggest that AMY2 is positively associated with IR. A high level of AMYt is related to lower glucose and insulin responses to OST in Mexican children, regardless of their weight status.

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RESUMEN Objetivo: Determinar el efecto del consumo de 3 tipos de leche de vaca (sin lactosa, alta en proteínas y estándar) sobre carga glicémica (CG), respuesta glicémica (RG) e índice glicémico (IG) y el nivel de saciedad en adultos sanos. Metodología: En 11 sujetos sanos se aplicó la metodología propuesta por la norma ISO 26642 para determinar índice glicémico. Se obtuvo muestra de sangre capilar a los 0, 30, 45, 60, 90 y 120 minutos. Se evaluó el nivel de hambre, saciedad y plenitud mediante escala visual análoga (EVA). El análisis estadístico se hizo mediante Test de Friedman, Wilcoxon, ajustado por Bonferroni o ANOVA de medidas repetidas. Significancia estadística con valor p0,05). Conclusión: Si bien la leche sin lactosa presentó un alto índice glicémico, ésta no afectó el nivel de saciedad. Por otro lado, la leche alta en proteínas y estándar tienen un bajo índice glicémico.

ABSTRACT Objective: To determine the effect of consumption of 3 types of cow's milk (lactose free, high in protein, and standard) on glycemic load (GL), glycemic response (GR) and glycemic index (GI) and the level of satiety in healthy adults. Methodology: Eleven healthy subjects participated. The methodology proposed by the ISO 26642 standard was applied to determine GI. Capillary blood sample was obtained at 0, 30, 45, 60, 90 and 120 minutes. The level of hunger, satiety and fullness were evaluated using a visual analog scale (VAS). Statistical analysis was done using the Friedman, Wilcoxon test, adjusted by Bonferroni or repeated measures ANOVA. Statistical significance was set as p0.05). Conclusion: Although lactose-free milk had a high GI, it did not affect satiety. On the other hand, high protein and standard milk have a low GI.

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BACKGROUND: Cystic fibrosis (CF) is an autosomal recessive disorder caused by pathogenic variants in the cystic fibrosis transmembrane conductance regulator (CFTR) gene. The CF variants incidence is highly variable and even undetermined in some countries like Mexico. METHODS: In this study, the allele frequencies of 361 variants in the CFTR gene were investigated in 1455 Mexicans without a CF or CFTR-related disorders (CFTR-RD) diagnosis. We also performed a statistical comparative analysis against allele frequencies of different populations to measure genetic differences in the prevalence of CFTR variants. RESULTS: In the vast majority of cases, the allele frequencies of this cohort were comparable to those found in other populations. However, some variants displayed significant differences in their allele frequencies when compared with European and African populations. CONCLUSIONS: This study provides information about CFTR variants to predict the prevalence of CF in Mexico and uncover other unknown but frequent pathogenic variants in the country. Additionally, other CFTR-RD variants have also been studied using population data of the same CFTR variants. Studies like this could help develop a regional molecular diagnostic screen to optimize the medical care of CF patients.

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Resumen Introducción: la dieta con restricción de proteínas parece tener un papel importante en la progresión de la enfermedad renal crónica (ERC) y la aparición anticipada de síntomas urémicos, además la suplementación de aminoácidos esenciales ofrece aparente seguridad para lograr restricciones agresivas de proteínas. Objetivo: realizar una revisión de la literatura para establecer las recomendaciones de uso práctico sobre la dieta con restricción de proteínas en la ERC avanzada. Materiales y métodos: se realizó una búsqueda estructurada rápida de la literatura en la que se incluyeron revisiones sistemáticas y metaanálisis, de los cuales se extrajeron las respuestas de las preguntas con estructura PICOT diseñadas a priori. Los resultados fueron sometidos a consenso para generar recomendaciones prácticas. Resultados: se incluyeron 6 revisiones sistemáticas de la literatura con una evaluación de calidad moderada. Según los hallazgos, una dieta muy baja en proteínas con suplementación de alfa-cetoanálogos beneficia a los pacientes que ingresan a diálisis o son sometidos a trasplante renal, además reduce la progresión de la enfermedad. No obstante, se requiere de ensayos clínicos con mejor calidad que consideren aspectos como la calidad de vida. Conclusiones: aunque la evidencia es de baja calidad, se establece que la dieta muy baja en proteínas y suplementada con alfa-cetoanálogos en pacientes adecuadamente seleccionados reduce el deterioro de la tasa de filtración glomerular y parece reducir el ingreso a diálisis. Por tanto, se recomienda hacer un seguimiento estricto y periódico en el que se vigilen las medidas antropométricas y el perfil de riesgo de desnutrición.

Abstract Introduction and objective: The protein-restricted diet appears to play an important role in the progression of chronic kidney disease and the early onset of uremic symptoms, the supplementation of essential amino acids offers apparent security in achieving aggressive protein restrictions. The objective of this document is to carry out a literature review to inform practical use recommendations on this behavior in advanced Renal Disease (CKD). Materials and methods: A quick structured search of the literature is carried out, with the selection of systematic reviews and meta-analyzes, from which the answers to the questions with a PICOT structure designed a priori are extracted. The results were submitted to consensus to generate practical recommendations. Results: six systematic reviews of the literature were included, with a moderate quality evaluation, the extraction of the information reports an apparent benefit of the very low protein diet with supplementation of alpha-keto-analogues on admission to dialysis or kidney transplantation and a consistent reduction of disease progression. Better clinical trials that integrate outcomes such as quality of life are required. Conclusions: With low quality of evidence, the very low protein diet, supplemented with alpha-keto analogues, in the properly selected patient, reduces the deterioration of the glomerular filtration rate, seems to reduce admission to dialysis. Regular strict monitoring is recommended, with monitoring of anthropometric measures and malnutrition risk profile.

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INTRODUCTION: The increasing resistance to antibiotics is a public health problem and an imminent therapeutic challenge in hospitals. In this report we aimed to analyze the relationship between antimicrobial resistance and antibiotic consumption in a third-level pediatric hospital. METHODOLOGY: A cross-sectional analysis was conducted using the information from the microbiology and pharmacy databases of the Pediatric Hospital "Doctor Silvestre Frenk Freund", during the period 2015-2018. Prevalence of antimicrobial resistance by microorganisms and dispensed grams of selected antibiotics were calculated annually. Antibiotic resistance trend over the time was evaluated using the Chi-square trends test and to assess the correlation between the dispensed grams of antibiotics with their antimicrobial resistance prevalence, we calculated the Pearson's coefficient (r). RESULTS: A total of 4,327 isolated bacterial samples were analyzed (56.5% Gram-positive and 44.5% Gram-negative). Most frequently isolated microorganisms were coagulase-negative staphylococci (CoNS), E. coli, K. pneumoniae, P. aeruginosa and S. aureus. We found a significant increase in resistance to clindamycin and oxacillin for CoNS and significant decrease in nitrofurantoin and amikacin resistance for E. coli and K. pneumoniae. We observed a strong positive and statistically significant correlation between amikacin resistance prevalence and amikacin dispensed grams for P. aeruginosa (r = 0.95, p = 0.05). CONCLUSIONS: The antibiotic resistance profile showed by our study highlights the need of an appropriate antibiotic control use in the Hospital setting.

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'Kerman' pistachios (KP; Pistacia vera L.) are an important crop for several countries but their commercial value is diminished by their shell dehiscence status and prolonged storage in popular marketplaces. The aim was to evaluate the independent/synergistic effect of prolonged storage (1-4 year) and dehiscence status (split/unsplit) on KP's morphometry and chemical composition. Whole nut's and kernel's length, width, thickness, surface area, and volume were more affected by dehiscence (split > unsplit; p ≤ 0.01) than storage time; Kernel's mass, macronutrient composition and tocopherols (T)/tocotrienols (T3) were not much affected by dehiscence but time-trend correlations were observed with macronutrient composition (split/unsplit; ρ = - 0.57-0.42) and T + T3 (unsplit; ρ = 0.81). Specific/total fatty acids were affected by a complex dehiscence × storage time interaction, and they linearly correlated with certain morphometric characteristics (r ≥ 0.6). Shell dehiscence status more than prolonged storage substantially modifies KP's quality.

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Abstract Introduction: The numbers of SARS-CoV-2 infection in the pediatric population are low so far. There is limited information about the behavior of SARS-CoV-2 in a pediatric patient with chronic kidney disease. Objective: To formulate informed recommendations to the prevention, diagnosis, and management of SARS-CoV-2 infection in pediatric patients with kidney disease or acute kidney injury associated with COVID-19 in Colombia. Methodology: A rapid systematic review was performed in Embase and Pubmed databases and scientific societies, to answer questions prioritized by clinical experts in pediatric nephrology. The quality of the evidence was evaluated with validated tools according to the type of study. The preliminary recommendations were consulted by an expert group. The agreement was defined when approval was obtained from at least 70% of the experts consulted. Results: A response was obtained from ' 9 experts in pediatric nephrology in Colombia, who declared the conflict of interest before the consultation. The range of agreement for the recommendations ranged from 78.9% to '00%. The recommendations did not require a second consultation. Conclusion: The evidence-based recommendations for the management of a patient with kidney disease and COVID-19 in the Colombian context are presented.

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Abstract Introduction: Acute kidney injury is a frequent complication in patients with COVID-19 and its occurrence is a potential indicator of multi-organ dysfunction and disease severity. Objective: Develop, through an expert consensus, evidence-based recommendations for the prevention, diagnosis, and management of acute kidney injury in patients with SARS CoV2 / COVID-19 infection. Materials and methods: Based on a rapid systematic review in Embase and Pubmed databases and documents from scientific societies, we made preliminary recommendations and consulted with an expert group through an online tool. Then we defined agreement after at least 70 % consensus approval. Quality evidence was evaluated according to the type of document included. The strength of the recommendations was graded as strong or weak. Results: Fifty clinical experts declared their conflict of interest; the consultation took place between May 2 and 29, 2020. The range of agreement ranged from 75.5 % to 100 %. Recommendations for prevention, diagnosis and management of acute kidney injury in patients with SARS CoV2 infection are presented. Conclusions: Although the good quality information available regarding acute kidney injury in patients with COVID-19 is scarce, the recommendations of clinical experts will guide clinical decision-making and strategies around patients with this complication, guaranteeing care focused on the people, with high quality standards, and the generation of safety, health and wellness policies for multidisciplinary care teams.

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