Abstract A novel method to classify the aggressiveness of soil considering its physicochemical content and the development of new synthetic solutions for lab uses is proposed. The results showed that the main criteria existing in the literature for soil corrosivity classification might cause misunderstandings about the real aggressiveness. The synthetic solutions proposed aim to cover a wide range of soil found worldwide in order to refine the assessment of their characteristics hence their corrosivity. For the lab experiments, an API 5L X65 pipeline carbon steel was used. The solutions presented great reliability, and they seemed to be adequate to simulate soils with the presence of sulfate-reducing bacteria (SRB), chloride, and high pH.

Resumo Este estudo objetivou caracterizar, em termos estruturais e ambientais pesqueiros localizados na sub-bacia da Guarapiranga. A região de estudo foi mapeada, e do total de 24 pesque-pague georreferenciados, 15 foram entrevistados com os proprietários através de questionários semi-estruturados e, nos sete pesque-pagues com tributários mais próximos da represa, foram coletadas amostras de água em um ciclo sazonal divididas em quatro coletas entre novembro de 2013 a agosto de 2014. Foram medidos in situ: vazão, pH, turbidez, condutividade elétrica e oxigênio dissolvido nos afluentes e efluentes, e também foram coletadas amostras de água para determinação da concentração de fósforo total (PT) e nitrogênio total (NT). Os resultados mostraram que há uma diminuição nas concentrações de oxigênio dissolvido e aumento nas concentrações de PT e NT nos efluentes em relação aos afluentes. Os efluentes apresentaram valores de PT e NT acima dos limites permitidos pela resolução CONAMA 357/2005 – Classe II, ao menos em um período do ano. Também foram identificados afluentes com cargas elevadas de nutrientes, característica de bacias impactadas pelo adensamento populacional. Através do questionário aplicado aos proprietários sobre o manejo dos empreendimentos e pelas análises de água verificou-se que houve correlação significativa entre o arraçoamento diário e as cargas de PT e de NT (p=0,021 e p=0,045, respectivamente), sendo que nos locais onde o arraçoamento foi mais intenso, a carga de nutrientes nos efluentes foi maior. Os resultados evidenciam a importância de medidas mitigadoras como orientações aos proprietários para o manejo adequado dos lagos, projetos de educação ambiental com os usuários para diminuir do uso de ceva para a captura dos peixes, além da instalação de aeradores artificiais nos lagos e tanques com filtros compostos de macrófitas aquáticas nos seus efluentes, minimizando os impactos na sub-bacia do Guarapiranga.

Abstract This study intended to characterize the fee-fishing ponds located in Guarapiranga's sub-basin both in terms of structure and environmental conditions. The studied region was mapped and 15 out of 24 georeferenced fee-fishing ponds had their owners interviewed through semi-structured questionnaires. In addition to that, samples were collected from the seven fee-fishing ponds closest to the reservoir throughout a seasonal cycle divided in four sample collections carried out between November 2013 and August 2014, aiming at measuring the following variables in situ: water flow rates, pH, turbidity, electrical conductivity and dissolved oxygen concentration in affluents and effluents. Other samples were taken in order to assess total phosphorus (TP) and total nitrogen (TN) concentrations. Our results show a decrease in dissolved oxygen concentration along with an increase in TP and TN concentration in effluents, as compared to affluents. TP e TN concentrations exceeded the permitted values established by CONAMA 357/2005 – Class II resolution in all effluents at least during part of the year. High nutrient levels were observed in affluents, condition with which basins that have been affected by population growth are commonly met. It was verified, by interviewing the owners regarding venture management and by analyzing the collected samples, that there is significant correlation between the daily feeding and the TP and TN levels (p=0.021 and p=0.045, respectively), with the ponds where feeding is more intense having showed the highest nutrient levels in their effluents. The results highlight the importance of mitigation measures such as educating the owners on proper water management, the installation of pond aerators in conjunction with tanks the filters of which shall be composed of aquatic macrophytes in their effluents, as well as awareness campaigns aiming to reduce the usage of dough by fishermen in order to minimize detrimental impacts on Guarapiranga’s sub-basin.

Abstract BACKGROUND: Venous thromboembolism (VTE) is a combination of pathologies, which can manifest during pregnancy as an isolated lower extremity deep vein thrombosis (DVT) or as a pulmonary embolus (PE). The global prevalence is low, which occurs in 1 to 1600 pregnancies. CLINICAL CASE: A 37-year-old primigravid patient with an episode of pulmonary thromboembolism with onset in the puerperium associated with intrapartum deep venous thrombosis as a triggering factor that evolved favorably due to timely diagnosis and treatment. CONCLUSION: The importance of this case lies in the need to act quickly to establish the diagnosis and immediately indicate the treatment.

Resumen ANTECEDENTES: la enfermedad tromboembólica es un cuadro clínico que puede manifestarse durante el embarazo, como un episodio aislado de trombosis venosa profunda en los miembros inferiores, o como tromboembolismo pulmonar. La prevalencia se considera baja: 1 caso por cada 1600 embarazos. El solapamiento de los síntomas de la enfermedad tromboembólica con el embarazo puede retrasar la sospecha clínica y complicar el establecimiento del diagnóstico. CASO CLÍNICO: paciente primigesta, de 37 años de edad, con un episodio de tromboembolismo pulmonar con inicio en el puerperio, asociado con trombosis venosa profunda intraparto como factor desencadenante que evolucionó favorablemente gracias al diagnóstico y tratamiento oportunos. CONCLUSIÓN: la importancia de este caso radica en la necesidad de actuar con rapidez para establecer el diagnóstico e indicar inmediatamente el tratamiento.

ABSTRACT In broiler production, the litter is reused for consecutives flocks, and it is treated during down time between flocks to reduce its microbial load. Although covering the litter with a plastic canvas is a common litter treatment in the field, there is little scientific information available on its efficacy. The aim of this study was to evaluate the effects of covering broiler litter with a plastic canvas for eight days on litter microbiological, physical, and chemical parameters, and on the intestinal microbiota and immunity of broilers. In the first trial, reused litter from a previous flock was distributed into three treatments, with six replicates each: L1 (negative control, litter free from Salmonella Enteritidis (SE) and Eimeria maxima (EM) and not covered), L2 (positive control, litter with SE and EM, and not covered), and L3 (litter with SE and EM, and covered with plastic canvas for eight days). Litter total bacteria, Enterobacteria, Lactobacillus, SE, and EM counts, and litter pH, temperature, moisture, and ammonia emission were determined on days 1 and 8. In the second trial, broilers were housed on those litters according to the treatments described above, and their intestinal microbiota, gut CD4+ and CD8+ lymphocytes and macrophages, and liver and intestinal pro-inflammatory interleukin (IFN-γ, IL-1β e IL-18) levels were evaluated on days 14 and 28. A significant reduction of litter bacterial populations was observed in the litter covered with plastic canvas. A significantly higher mRNA IFN-γ gene expression (12.5-fold) was observed in the jejunum and liver of broilers reared on the litter with Enterobacteria counts. No EM reduction was observed in the covered litter. Covering reused broiler litter with plastic canvas reduces initial litter bacterial load as a result of the interaction between physical and chemical parameters.

Background. To validate scales to measure adolescent attitudes toward sexuality (EAS), toward addictive substances (EASA) and toward vial security (EASV), and to examine their correlations with behaviour on these areas. Methods. We designed the scales by literature review; we validated their content using a Delphi-on-line panel with 18 experts, and a pre-test with a sample of 21 fourth-grade high-school students (similar to 10th in US) in Seville, Spain. The scales were administered to 188 fourth-grade high-school students in order to test their construct validity (exploratory factor analysis), their reliability (Alpha Cronbach test), and to determinate their correlations with age, gender, experience of sexual intercourse, substance use and road behaviour. Results. EAS-10 obtained α=0.73, EASA-12 obtained α=0.80, EASV-12 obtained α=0.79. They showed evidence of one-dimensional interpretation after factor analysis, a) all items achieved weights r>0.30 in the first factor, which explained a significant proportion of variance before rotations, and b) total variance explained by the main factors extracted was greater than 50%. We found correlations between EASA-12 and tobacco use (r=-0.43, p<0.001), alcohol use (r=-0.30, p<0.001), age of alcohol initiation (r=0.32, p=0.003), and substance use (r=-0.55, p<0.001), and between EASV-12 and safe road behaviour (r=0.41, p<0.001), tobacco use (r=-0.23, p=0.003), alcohol use (r=-0,22, p=0,003), age of first experience of drunkenness (r=0.22, p=0.003), and substance use (r=-0.27, p=0.013). Conclusions. The scales showed their reliability and validity. They could be employed for assessing adolescent attitudes to these priority intervention areas, for carrying out studies on their mediating role on adopting behaviour, and for designing and evaluating health programs.

Fundamento. Validar escalas para evaluar la actitud adolescente hacia la sexualidad (EAS), las sustancias adictivas (EASA) y la seguridad vial (EASV), y examinar sus relaciones con comportamientos en dichas áreas. Material y métodos. Se diseñaron las escalas mediante revisión bibliográfica, se validó su contenido mediante panel Delphi on-line con 18 expertos y pretest con 21 alumnos de cuarto de educación secundaria obligatoria en Sevilla. Éstas se administraron junto a preguntas sobre comportamientos a otros 188 alumnos para determinar su validez de constructo (análisis factorial exploratorio), fiabilidad (Alfa de Cronbach) y su correlación con las variables: edad, género, inicio de relaciones sexuales, consumo de sustancias y prácticas viales. Resultados. La escala EAS-10 obtuvo un α=0,73, EASA-12 de α=0,80, y EASV-12 de α=0,79. Mostraron evidencias de unidimensionalidad en el análisis factorial, a) pesos r>0,30 en el primer factor, que explicaba una proporción importante de varianza, b) varianza total explicada por factores principales mayor al 50%. Se encontraron correlaciones entre EASA-12 y experimentación con tabaco (r=-0,43, p<0,001) y alcohol (r=-0,30, p<0,001), edad de inicio al alcohol (r=0,32, p=0,003), edad de la primera borrachera (r=0,31, p=0,003), y consumo de sustancias (r=-0,55, p<0,001), y entre EASV-12 y practicas viales seguras (r=0,41, p<0,001), experimentación con tabaco (r=-0,23, p=0,003) y alcohol (r=-0,22, p=0,003), edad de la primera borrachera (r=0,22, p=0,003), y consumo de sustancias (r=-0,27, p=0,014). Conclusiones. Las escalas demostraron validez y fiabilidad. Pueden ser utilizadas para valorar la actitud de adolescentes españoles hacia estas áreas, determinar su papel mediador en la adopción de comportamientos y diseñar y evaluar programas de salud.

The skin disorders are derived in most cases continuous injuries by external factors that have how responses the loss of epidermal lipids by the effect of moisture, derived of changes in skin pH (alkalinization), an increased coefficient of friction (denudation) and the imbalance of the saprophytic flora of the skin, give how a result an increase to the irritative processes and the fungal and bacterian infections in the area exposed to moisture. Given the importance of assessing the quality of life of patients with dermatitis who are treated with No Sting Barrier Film (NSBF) CavilonTM has developed a multicenter study, in order to evaluate the related to improving the quality of care that patients Incontinence Dermatitis with ESCLI scale. Patients included in the study were 25. The results show a significant improvement aspects ESCLI assessed by the scale of the evolution of the dermatitis. This scale assesses aspects such as the area affected by the redness and severity. Show a reversal 47% of cases. The denudation of the skin in the diaper area disappears in 56% of cases and the severity of the denudation which has a 47% improvement. The assessment of pain in the area of incontinence, is reduced by 76% in the area of incontinence and a 73% when cleaning the area. The findings of this study prove indicates that the application of forming products of a No Sting Barrier Film (NSBF) in patients with incontinence dermatitis is an alternative to conventional treatments such as creams or ointments or zinc oxide paste water. The reversal and reduction of dermatitis is an aspect that has improved important. The results that we can relate to quality of life or longer specifically with the improvement of pain are significant.

Los trastornos cutáneos son derivados, en la mayoría de las ocasiones, de agresiones continuas por elementos externos que tiene como respuesta reacciones como la pérdida de lípidos epidérmicos por efecto de la humedad, cambios en el pH cutáneo (alcalinización) y aumento del coeficiente de fricción (denudación) junto al desequilibrio de la flora saprofita de la piel, que se traducen en procesos irritativos y en un aumento de la infecciones fúngicas y bacterianas en la zona expuesta a humedad. Dada la importancia de evaluar la calidad de vida de los pacientes con dermatitis que son tratados con productos barrera no irritantes (PBNI) se ha desarrollado un estudio multicéntrico, con el objetivo de evaluar los aspectos relacionados con la mejora en la calidad de cuidados a pacientes tratados con Cavilon® que presentaban dermatitis por incontinencia mediante la escala ESCLI. Los pacientes incluidos en el estudio fueron 25. Los resultados muestran una mejora importante de los aspectos evaluados mediante la escala ESCLI sobre la evolución de la dermatitis. Esta escala valora aspectos como el área afectada por el enrojecimiento y la severidad, presentan una reversión del 47% de los casos. La denudación de la piel en la zona del pañal desaparece en el 56% de los casos y la severidad de la denudación que presenta una mejoría del 47%. La valoración del dolor en la zona de incontinencia se reduce en un 76% en la zona de incontinencia y en un 73% al realizar la limpieza de la zona. Las conclusiones del presente estudio ponen de manifiesto que la aplicación de productos formadores de una película barrera no irritante (PBNI) en los pacientes que presentan dermatitis por incontinencia representa una alternativa a los tratamientos convencionales como son las cremas o ungüentos de óxido de cinc o pastas al agua. La reversión y reducción de la dermatitis es un aspecto que presenta una mejoría importante. Los resultados obtenidos que podemos relacionar con la calidad de vida o más concretamente con la mejora del dolor son destacables.

Atualmente, as ligas de alumínio da série 6xxx vêm ocupando um espaço importante na produção global das ligas de alumínio. A utilização em larga escala dessa classe de ligas é consequência da melhoria de suas propriedades mecânicas quando submetidas a tratamentos térmicos. No entanto, a realização de tratamentos térmicos de solubilização e a precipitação de fases metaestáveis durante o envelhecimento podem prejudicar consideravelmente a resistência à corrosão dessa classe de ligas. O presente trabalho, objetiva avaliar a suscetibilidade à corrosão da liga de alumínio 6101 submetida a tratamentos térmicos de solubilização. Investigou-se a corrosão através da realização de ensaios de potencial ao longo do tempo e curvas anódicas de polarização. Avaliou-se qualitativamente a formação de pites através de microscopia eletrônica de varredura (MEV). As soluções de 3,5 % de NaCl e 0,1 M de Na2SO4 foram utilizadas nos ensaios para simular condições de alta agressividade

Currently, 6xxx series aluminum alloys have been occupying an important place in the global production of aluminum alloy. The wide use of this class of alloys is a result of improvement on mechanical properties when subjected to heat treatments. However, the thermal treatments of solubilization and precipitation of metastable phases during aging may impair the corrosion resistance of this class of alloys. The present study aims to evaluate the corrosion behavior of aluminum alloy 6101 after heat treatment of solubilization by testing over time and anodic polarization curves. The formation of pits was evaluated by scanning electron microscopy (SEM). Solutions of 3.5 % NaCl and 0,1 M Na2SO4 were used in order to simulate conditions of high aggressiveness.

Background: intraductal papillary mucinous neoplasm (IPMN) shows a series of lesions which evolve from benign lesions -adenoma- to invasive carcinoma. Aim: to analyze the clinical and pathological results of 15 patients diagnosed of IPMN, and surgically treated according to the guidelines of International Consensus Conference. Material and methods: a retrospective analysis of 15 patients surgically treated between March 1993 and September 2009, according to the International Consensus recommendation. Demographic, diagnostic tools, surgical report, pathologic database and actuarial survival were analyzed with a follow-up from one and a half month through nine years. Results: 6 patients underwent pancreaticoduodenectomies, 4 total pancreatectomies, 2 body or central pancreatectomies, 2 partial pancreatectomies (enucleation) and 1 distal pancreatectomy. A morbidity of 46 and 0% hospital mortality were assessed, with a median length hospital stay of 10 days. In five cases, the IPMN was combined type (both main and branch pancreatic ducts involved) in four main duct-type and branch duct-type in the another six as well. Several atypia (IPMN carcinoma in situ) was observed in 2 patients and invasive carcinoma with negative lymph nodes was identified in 3 patients. A patient without invasive carcinoma died at 66 months of follow-up for pancreas adenocarcinoma. The actuarial survival up to recurrence or death was 105,133 months with a range of follow-up from 1 month and a half until 9 years. Conclusions: IPMN main duct or mixed type warrants complete resection due to its incidence of invasive carcinoma or precursor lesions of malignancy as well. Due to its multifocal pattern, patients should be followed in long-term surveillance. The management of asymptomatic IPMN type branch less than 3 cm is controversial.

Introducción: la neoplasia papilar mucinosa intraductal (NPMI) del páncreas comprende una serie de lesiones que evolucionan desde lesiones benignas (adenoma) hasta carcinoma ductal invasivo. Objetivo: analizar los resultados clínicos y patológicos de 15 pacientes diagnosticados de NPMI e intervenidos según las recomendaciones de conferencia de consenso. Material y métodos: análisis retrospectivo de 15 pacientes con NPMI, intervenidos entre marzo de 1993 y septiembre de 2009; según pautas de conferencias de consenso internacionales. Se recogieron datos demográficos, pruebas diagnósticas, tipo de intervención, histopatología y supervivencia actuarial con un seguimiento entre mes y medio y nueve años. Resultados: se realizaron 6 duodenopancreatectomías cefálicas, 4 pancreatectomías totales, 2 pancreatectomías centrales, 2 pancreatectomías parciales y una pancreatectomía distal. Se registró una morbilidad del 40%, sin mortalidad operatoria, con una estancia media de 10 días. En 5 casos la NPMI fue de tipo mixto, en 4 afectaba al conducto pancreático y en los 6 restantes a ramas accesorias. Dos pacientes presentaron carcinoma in situ y 3 carcinoma invasivo con ganglios negativos. Un paciente, sin carcinoma invasivo, falleció a los 66 meses por adenocarcinoma de páncreas. La supervivencia actuarial hasta recidiva o muerte fue de 105,133 meses; con un rango de seguimiento entre mes y medio y 9 años. Conclusiones: la NPMI tipo ductal y mixto exige la resección completa debido a la elevada incidencia de carcinoma invasivo o de lesiones precursoras de malignidad. Por su carácter multifocal los enfermos deben ser revisados a largo plazo. Existen controversias en las NPMI tipo accesorio asintomáticas y menores de 3 cm.

The celiac axis compression syndrome (CACS) due to median arcuate ligament (MAL) was first described by Harjola in 1963; originating postpandrial abdominal pain, weight loss, epigastric bruit and celiac axis stenosis > 75% in angiographic studies. This clinical condition has been the origin of controversies about its pathogenesis, diagnosis and its long term clinical results. Advances in diagnostic imaging as 64 multidetector-row CT (MDCT), 3-D reconstruction, magnetic resonance (MR) and color duplex ultrasonography, provide better understanding of the syndrome and allow to identify the best candidates for surgical division of MAL fibers. Since the introduction of laparoscopic approach, and also endovascular procedures, in 2000, a new perspective has established in this challenging syndrome. With the occasion of our own experience, a critical review of the syndrome is presented.

El síndrome de compresión del tronco celiaco fue descrito por Harjola en 1963 como la compresión extrínseca del tronco celiaco por las fibras tendinosas del ligamento arcuato; causando un cuadro de dolor intenso post-pandrial en epigastrio, pérdida de peso, soplo epigástrico y estenosis mayor del 75% en la angiografía selectiva. Desde entonces, dicho síndrome ha sido motivo de múltiples controversias relacionadas con su patogenia y la variabilidad de los resultados obtenidos con la cirugía. Debido a la proliferación y accesibilidad de técnicas de imagen más precisas y menos invasivas (angio-TAC multicorte, angio-RMN, eco-doppler), el diagnóstico de dicho síndrome puede realizarse con mayor precisión y sentar las bases de la indicación quirúrgica con mayor seguridad y eficacia. La introducción, en el año 2000, de técnicas laparoscópicas en la liberación del tronco celiaco, junto con procedimientos endovasculares complementarios, ha representado un notable avance en el tratamiento del síndrome. Basados en nuestra experiencia personal, presentamos una revisión crítica y propuesta terapéutica del síndrome.

The Peutz-Jeghers syndrome (PJS) is an autosomal dominant hamartomatous poliposis describred in 1921. Hemminki in 1997 described the presence of LKB-1 mutation tumor-suppressor gen. The patients with PJS develop a higher cumulative incidence of gastrointestinal, pancreas and extraintestinal tumors, being occasion of a renew interest on hamartomatous polyposis syndromes regarding the clinical care, cancer surveillance treatment and long term follow-up. We report the case of a 38 years old male, diagnosed of PJS who developed a multiple adenocarcinoma in duodenum and yeyunum. Surgically treated and with a long-term free disease survival of 11 years represents the sixth case reported in the spanish literature of PJS associated with a gastrointestinal tumor. A critical review, molecular alterations and the established criteria of tumor screening and surveillance are reviewed.

Environmentally induced cracking of pipeline steels in contact with soil have been investigated. Different soils were prepared in order to determine their physical, chemical and bacteriological characteristics. Slow strain rate testing was carried out by using electrolytes obtained from soil samples and NS4 standard solution. Stress vs. strain curves of API 5L grade X46, X60 and X80 steels were obtained at different electrode potentials (Ecorr, 100 mV below Ecorr and 300 mV below Ecorr) with 9 x 10-6 s-1 strain rate. The results obtained with API 5L X46 in soil solution were compared with slow strain rate test (SSRT) results obtained using a strain rate of 9 x 10-7s-1 to the same steel. All results showed the incidence of cracking and their dependence on the potential imposed, revealing the SCC (Stress corrosion cracking) susceptibility of the steels. It was also observed that the hydrogen embrittlement - HE - has an important contribution to cracking initiation and propagation. Cracking morphology was similar to the SCC reported on field condition where transgranular cracking were detected in a pipeline collapsed by land creeping. It was important to point out that even under cathodic potentials the material showed the incidence of secondary cracking and a significant reduction of ductility.

Production systems of ruminants present different efficiencies in the use of energy. The transformations that take place in the process of energy partition in ruminants should be studied in order to reach alternatives of nutritional management that result in a reduction of losses and an increase in the energy retained in usable products. Actions that favour an increase in the digestibility of feed will result in a greater intake of digestible energy. These include an adequate N intake, additives such as exogenous enzymes and some treatments for residues or grains. In order to increase metabolisable energy (ME), it is necessary to reduce energy losses in urine and fermentation gases. For the first, excesses of degradable N compounds in the rumen should be avoided in the diet and the use of ruminally protected amino acids. For the second, the end products of fermentation in accordance with the forage:concentrate ratio and the use of ionophores should be considered. In order to increase net energy, it is necessary to reduce heat production, which is not easy as there is heat production associated with basal metabolism, activity and caloric exchange, and intake of ME. It is important to consider the possible nutritional strategies that may increase the efficiency of energy use in the different production systems.

Los sistemas de producción de bovinos difieren en la eficiencia de utilización de la energía. Las transformaciones en el proceso de la partición de la energía de los rumiantes deberían ser estudiadas para buscar alternativas de manejo nutricional que permitan reducir las pérdidas e incrementar la energía retenida en productos utilizables. Las prácticas que permitan incrementar la digestibilidad del alimento, repercutirán en un mayor consumo de energía digestible, tales como consumo adecuado de N, aditivos como enzimas exógenas, y algunos tratamientos de esquilmos o de granos. Para incrementar la energía metabolizable (EM) es necesario reducir las pérdidas de energía en orina y en gases de la fermentación. Para lo primero se deben de evitar excesos de compuestos nitrogenados degradables en rumen en la dieta y el uso de amino ácidos protegidos de la degradación ruminal. Para lo segundo habrá que considerar los productos finales de la fermentación de acuerdo a la relación forraje:concentrado y el uso de ionóforos. Para aumentar la energía neta, es necesario reducir el calor producido, lo cual no es sencillo dado que existe producción de calor asociada con el metabolismo basal, la actividad y el intercambio calórico y el consumo de EM. Es importante considerar las posibles estrategias nutricionales que puedan incrementar la eiciencia de utilización de la energía en los diferentes sistemas de producción.

En este trabajo se comparan dos técnicas de control vectorial que permiten regular la inyección de potencia activa y reactiva instantánea en un sistema de potencia. El primer método se fundamenta en la aplicación de la estrategia utilizada en los Controladores Directos de Par (DTC, siglas en inglés) que se vienen utilizando en la regulación de velocidad de las máquinas de corriente alterna. La segunda propuesta desarrollada por los autores, utiliza la optimización del vector espacial de la tensión del puente convertidor para reducir el error medio cuadrático de las potencias activas y reactivas instantáneas. Ambos mecanismos de control presentan ventajas y desventajas en sus características que combinadas permiten mejorar la respuesta dinámica y estática del Controlador Directo de Potencia (CDP). El nuevo sistema de control propuesto es inmune a las distorsiones armónicas presentes en la red y permite la regulación prácticamente instantánea (< 10ì s) del flujo de potencias activas y reactivas tal como lo demuestran las simulaciones realizadas.

This paper compares two space vector techniques that can be used to regulate the instantaneous active and reactive power flow in a Power System. The first method uses the Direct Torque Control (DTC), employed frequently on speed regulation of the AC machines. The second one proposed by authors, uses the optimization of the space vector voltage in a controller bridge to reduce the least square error by controlling the instantaneous active and reactive power. These control methods have several advantages and disadvantages and are combined to improve the static and dynamic Direct Power Control (DPC) performance. The new proposed control system is no affected by harmonic distortion in the network and the obtained regulation of active and reactive power flow is practically instantaneous (< 10ì s) as is shown by performed simulations.