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Sample records for celulas progenitoras derivadas

  1. Regeneracion osea por implante de celulas madre mesenquimales derivadas de tejido adiposo humano en un modelo animal

    Linero Segrera, Itali Marcelly

    2012-01-01

    La reconstrucción y restauración de la función esquelética continúa siendo un reto en el campo de la cirugía maxilofacial y la ortopedia. Una alternativa o terapia coadyudante a los tratamientos convencionales es la ingeniería de tejidos que surge como una posibilidad prometedora para la regeneración del tejido óseo. Con el fin de crear un modelo para la aplicación clínica de las células madre mesenquimales derivadas de tejido adiposo humano (Ad-MSCs) desarrollamos una matriz tridimensi...

  2. Trasplante autólogo de células progenitoras derivadas de la médula ósea, por vía intramiocárdica, para revascularización en cardiopatía isquémica crónica Autologous intramyocardial transplant of bone marrow derived stem cells for revascularization in ischemic chronic cardiopathy

    Óscar Velásquez

    2005-08-01

    Full Text Available Introducción: estudios experimentales y clínicos demuestran que la implantación intramiocárdica de células progenitoras derivadas de la médula ósea, produce angiogénesis y mejora la función cardiaca en pacientes con cardiopatía isquémica crónica. Metodología: este es el reporte del seguimiento a dos meses de un paciente con cardiopatía isquémica crónica no susceptible de revascularización quirúrgica o percutánea, a quien se le realizó ,por vía epicárdica, un implánte de células progenitoras derivadas de médula ósea movilizadas con factor de crecimiento granulocito-macrófago. Resultados: se demostró mejoría significativa en la sintomatología, en la capacidad funcional (1.8 MET a 10 MET, en el estado funcional (IV a I, en el tamaño del defecto de perfusión miocárdica por medicina nuclear, en la fracción de eyección y en la disminución del volumen sistólico final del ventrículo izquierdo, sin observar complicaciones relacionadas con el procedimiento. Conclusión: el trasplante de células progenitoras derivadas de la médula ósea es una terapia efectiva y segura para promover neovascularización y para mejorar la contractilidad y la perfusión miocárdica en los pacientes con cardiopatía isquémica crónica pobres candidatos a cirugía.Introduction: experimental and clinical studies have demonstrated that intramyocardial bone marrow derived stem cells implantation produce angiogenesis and improvement of cardiac function in patients with chronic ischemic cardiopathy. Methodology: this is a two months follow-up report of a patient with chronic ischemic cardiopathy not susceptible of surgical or percutaneous revascularization, to whom bone marrow stem cells mobilized with granulocyte - macrophage growth factor was implanted. Results: significant improvement was demonstrated in symptomatology, functional capacity (1.8 Mets to 10 Mets, functional state (IV to I, size of the myocardial perfusion defect by nuclear

  3. Caracterização do perfil de colonização oral por Candida spp. em pacientes submetidos a transplante de celulas progenitoras hematopoieticas no Hospital de Clinicas da UNICAMP

    Monica Leal Alcure

    2006-01-01

    Resumo: As infecções superficiais e sistêmicas provocadas por Candida são freqüentes causas de morbidade e mortalidade em pacientes submetidos a transplante de células progenitoras hematopoiéticas (TCPH). Entre os fatores de risco destaca-se a colonização prévia a qual parece ser um pré-requisito para o desenvolvimento de infecção. Desta forma, a cavidade oral pode atuar como um reservatório para esses microorganismos. O presente estudo teve como objetivo avaliar, prospectivamente, o fluxo sa...

  4. Trasplante de células progenitoras derivadas de la médula ósea y factor de crecimiento granulocítico en cardiopatía isquémica aguda y crónica Transplant of stem cells derived from bone marrow and granulocytic growth factor in acute and chronic ischemic myocardiopathy

    Juan M Senior

    2007-12-01

    Full Text Available Introducción: estudios recientes demuestran la seguridad y eficacia de la implantación de células progenitoras derivadas de la médula ósea y de la administración del factor estimulante de colonias de granulocito en pacientes con infarto agudo del miocardio con elevación del segmento ST y en cardiopatía isquémica crónica. Se diseñó un estudio prospectivo, abierto de «antes y después» para evaluar la seguridad y eficacia de la terapia celular asociada a la administración del factor de crecimiento. Se reporta la primera experiencia con este tipo de terapia. Metodología: este es el reporte del seguimiento a seis meses, de los pacientes con cardiopatía isquémica aguda y crónica a quienes se les realizó trasplante de células progenitoras derivadas de la médula ósea, movilizadas con factor de crecimiento estimulante de colonias de granulocitos, por vía intracoronaria o epicárdica. Se incluyeron dos grupos de pacientes: 1. Diez pacientes con infarto de pared anterior y 2. Cinco pacientes con cardiopatía isquémica crónica, todos con necrosis extensa demostrada por ausencia de viabilidad miocárdica por medicina nuclear y fracción de eyección menor del 40%. Resultados: se demostró mejoría significativa de la fracción de eyección de 29,44 ± 3,36 a 37,6 ± 5,3 con pIntroduction: recent studies have shown the safety and efficacy of the stem cells derived from bone marrow (BMC implant with concomitant administration of stimulating factor of granulocyte colonies in patients with acute myocardial infarction with ST segment elevation and in chronic ischemic cardiopathy. An open prospective «before and after» design was made to evaluate the safety and efficacy of cell therapy associated to growth factor administration. The first experience with this kind of therapy is reported. Methodology; this is a 6 months follow-up report of patients with acute and chronic ischemic cardiopathy to whom transplant of stem cells derived from

  5. Tratamento da Osteonecrose da Cabeça Femoral com celulas progenitoras autólogas em anemia falciforme Femoral Head Necrosis treatment with autologous stem cells in sickle cell disease

    Gildásio Cerqueira Daltro

    2008-01-01

    Full Text Available OBJETIVO: Avaliação da segurança e eficácia do uso de células progenitoras autólogas da medula óssea (CMMO no tratamento da Osteonecrose da Cabeça Femoral (OCF de pacientes portadores de anemia falciforme. MÉTODOS: Foram estudados 8 pacientes portadores de anemia falciforme, com OCF nos estágios I e II (classificação de Ficat e Arlet. As CMMO retiradas da crista ilíaca posterior foram concentradas e reinfundidas na área central da osteonecrose. Os principais parâmetros avaliados foram segurança, sintomas clínicos e progressão da doença, através da avaliação clínica (Harris Hip Score e radiológica. RESULTADOS: A maior parte dos pacientes (7 em 8 referiu melhora dos sintomas após o tratamento. Não houve complicações durante o procedimento anestésico e cirúrgico. A medida do escore (Harris Hip Score no pré-operatório foi 78,5 +/- 6,2 pontos, com aumento significativo destes valores no pós-operatório (98,3 +/- 2,5 pontos (pPURPOSE: To assess the efficacy and safety of autologous bone-marrow mononuclear cells (BMMC implantation in necrotic lesions of the femoral head in patients with sickle cell disease. METHODS: We studied eight patients with stage-I or -II femoral head osteonecrosis according to the system by Ficat and Arlet. BMMCs were harvested and re-infused into the necrotic zone. The primary endpoints studied were safety, clinical symptoms and disease progression, these being assessed according to the Harris hip score (HHS and to X-ray studies. RESULTS: After eight months, seven of the eight patients reported improvement from symptoms. There were no complications during anesthetic and surgery procedures. There was a significant postoperative increase in the HHS (98.3 +/- 2.5 points compared to preoperative HHS (78.5 +/- 6.2 points (p< 0.001. X-ray evaluation and cell parameters were found to be favorable. CONCLUSION: The autologous bone-marrow mononuclear cells implantation seems to be a safe and effective

  6. La disyuntiva de Dios: ¿derivadas enteras o fraccionarias?

    Jorge Fujioka Rojas

    2016-01-01

    Full Text Available Se presentan conceptos básicos del cálculo fraccionario. Para ello, se describe una delas primeras disyuntivas que enfrentó Dios el primer día de la creación: ¿escribiría las leyes físicasen términos de derivadas enteras o fraccionarias? Para salir de esta duda Dios examina lo quepasaría si en la segunda ley de Newton pusiera una derivada fraccionaria, en lugar de la segundaderivada usual. Dios resuelve este problema mediante la transformada de Laplace y esto lo conduceal descubrimiento de la función de Mittag-Leffler.

  7. Situación didáctica del concepto de derivada

    Camacho, Alberto; Sánchez, Bertha Ivonne

    2004-01-01

    Proponemos introducir el concepto de derivada mediante una aplicación de la velocidad media, utilizando un simulador y el desarrollo en serie de funciones, a partir de lo cual los estudiantes proporcionen una definición de la derivada.

  8. Celulas solares e sensores de filme fino de silicio depositados sobre substratos flexiveis =

    Pinto, Emilio Sergio Marins Vieira

    Celulas solares flexiveis de filmes finos de silicio sao geralmente fabricadas a baixa temperatura sobre substratos de plastico ou a mais elevadas temperaturas sobre folhas de aco. Esta tese reporta o estudo da deposicao de filmes finos sobre diferentes substratos de plastico, transparentes e coloridos, para celulas solares do tipo sobrestrato e substrato, respectivamente. Como objetivo co-lateral, os filmes dopados depositados sobre plastico foram usados como sensores de deformacao, utilizando as suas propriedades piezo-resistivas. Elevadas taxas de deposicao dos filmes de silicio depositados sobre plastico foram obtidas a baixa temperatura do substrato (150ºC) por rf-PECVD. A influencia de diferentes parametros de deposicao sobre as propriedades e taxa de deposicao dos filmes resultantes foram estudados e correlacionados. Celulas solares de filmes finos de silicio amorfo e microcristalino foram desenvolvidas a baixas temperaturas sobre plasticos. Eficiencias de 5 - 6.5% foram alcancadas para as celulas amorfas e 7.5% para as celulas microcristalinas. Efeitos de aprisionamento da luz foram estudados atraves da texturizacao por ablacao laser de substratos de plastico e corrosao umida de TCO sobre plastico. Filmes finos de silicio microcristalino, depositados por HW-CVD, com fator piezoresistivo de -32.2, foram usados para fabricar sensores de deformacao em uma membrana plastica muito fina (15 μm). Estruturas de teste em textil e a miniaturizacao dos sensores piezoresistivos depositados sobre substratos flexiveis de poliimida foram abordados.

  9. Aplasia pura de serie roja post-trasplante alogeneico de células progenitoras hematopoyeticas ABO incompatible

    E. Bulliorsky

    2002-12-01

    Full Text Available El trasplante alogeneico de células progenitoras hematopoyéticas (TCPH con incompatibilidad ABO entre el donante y el receptor puede en ocasiones asociarse a trastornos en la progenie eritroide desarrollada a partir de la médula ósea trasplantada, caracterizado por un funcionamiento tardío, inadecuado e incompleto de la misma. En este contexto, la aplasia pura de serie roja es la complicación más severa. Se han intentado tratamientos para la aplasia pura de serie roja post-TCPH con eritropoyetina o plasmaféresis, con relativo éxito. Algunos autores han informado también la utilización de globulina antilinfocitaria, asumiendo que dicha aplasia selectiva de la serie roja en la médula ósea trasplantada es mediada por un mecanismo inmune. En este trabajo se describe un paciente portador de una leucemia aguda en quien se realizó un TCPH alogeneico (ABO incompatible con su donante. Teniendo niveles bajos de aglutininas contra el grupo sanguíneo de la donante, desarrolló una aplasia pura de serie roja post - TCPH. La misma no mejoró con tratamiento con eritropoyetina o con un refuerzo de progenitores hematopoyéticos de sangre periférica de la misma donante (boost, resolviéndose totalmente luego de un tratamiento exitoso con globulina antilinfocitaria de origen equino.

  10. Trasplante de células progenitoras hematopoyéticas en enfermedades autoinmunes Hematopoietic stem cell transplantation in autoimmune diseases

    Flavio Albarracín

    2008-04-01

    Full Text Available El trasplante de células progenitoras hematopoyéticas, células con capacidad de autorrenovación y reconstitución de todos los tipos de células sanguíneas, se utiliza en el tratamiento de numerosas enfermedades potencialmente letales incluyendo leucemias y linfomas. Hoy en día es posible además aplicarlo en el tratamiento de enfermedades autoinmunes graves, como esclerosis múltiple, lupus eritematoso sistémico o esclerosis sistémica, resistentes a la terapia convencional. Estudios en modelos animales nos demuestran que la transferencia de células progenitoras hematopoyéticas podría revertir el proceso de autoinmunidad, un fenómeno que puede explicarse mediante diferentes mecanismos. El resultado de los estudios clínicos que se están llevando a cabo, así como también estudios en pacientes y modelos animales, ayudarán a determinar el rol que el transplante de células progenitoras hematopoyéticas puede jugar en el tratamiento de enfermedades autoinmunes.Transplantation of hematopoietic stem cells, which are capable of self renewal and reconstitution of all types of blood cells, can be a treatment for numerous potential lethal diseases, including leukemias and lymphomas. It may now be applicable for the treatment of severe autoimmune diseases, such as therapy-resistant multiple sclerosis, lupus and systemic sclerosis. Studies in animal models show that the transfer of hematopoietic stem cells can reverse autoimmunity. The outcome of ongoing clinical trials, as well as of studies in patients and animal models, will help to determine the role that stem-cell transplantation can play in the treatment of autoimmune diseases.

  11. Evaluación de los niveles plasmáticos de células progenitoras en pacientes con enfermedad coronaria crónica

    Juan Gagliardi

    2007-01-01

    Full Text Available IntroducciónEl ejercicio físico es útil para los pacientes con enfermedad coronaria y es un estímulo para el desarrollo de circulación colateral. Ésta podría estar determinada por un aumento en la producción y circulación de células progenitoras.ObjetivoEvaluar el efecto del ejercicio físico programado sobre la producción y el número circulante de células progenitoras en pacientes coronarios crónicos estables.Material y métodosEstudio prospectivo, controlado, aleatorizado y abierto con la inclusión de 18 pacientes (8 en grupo ejercicio y 10 en grupo control con enfermedad coronaria estable, < 75 años, que no hubieran participado en grupos de ejercicio programado en los últimos 3 meses. La determinación de las células progenitoras se realizó por citometría de flujo utilizando marcaciones con anticuerpos monoclonales CD45-FITC, CD34-FITC y CD133/1-PE.ResultadosEn el grupo control, el nivel de CD45 no tuvo variación significativa (0,724 ± 0,256 versus 0,765 ± 0,216 [media ± EE cada 100.000 eventos], mientras que en el grupo ejercicio el nivel de CD45(+/CD133(+ se incrementó de 0,497 ± 0,161 a 2,265 ± 1,003 luego de un mes de actividad física programada sin alcanzar significación estadística.Al analizar los niveles de CD34 se observó que en el grupo control se incrementaron de 0,196 ± 0,086 a 0,235 ± 0,063 (p = NS. En el grupo ejercicio, la variación fue mucho mayor: 0,220 ± 0,078 a 0,844 ± 0,172 (p = 0,0046; p = 0,0092 versus el grupo control. ConclusiónEl ejercicio físico programado en pacientes coronarios promueve un incremento de las células progenitoras circulantes. Su estímulo persistente podría ser la base para un mayor desarrollo de circulación colateral.

  12. Descripción de niveles de comprension del concepto derivada.

    Claudia Salazar Amaya

    2010-10-01

    Full Text Available Este artículo presenta un estudio de caso que describe los niveles de comprensión del concepto derivada de seis estudiantes que cursaron el espacio académico cálculo diferencial en el II semestre de 2007 en la Licenciatura en Matemáticas de la Universidad Pedagógica Nacional. El marco teórico utilizado se concentra en el desarrollo del esquema de derivada a través de tres niveles: Intra, Inter, Trans (Piaget y García, 1983, 1989. Se dedujo el nivel de comprensión alcanzado por los participantes a partir del análisis de las respuestas que dieron a diferentes problemas planteados en tres cuestionarios. Se encontró una tendencia en algunos a interpretar la derivada en términos del proceso algorítmico y también como dependencia de la expresión algebraica de la función. Por otra parte, se hicieron evidentes las dificultades para transitar de la gráfica de la función hacia la gráfica de la función derivada.

  13. Introducción al concepto derivada: Un diseño experimental con estudiantes universitarios de humanidades

    Sandoval, Juan Carlos

    2014-01-01

    La investigación presenta una propuesta didáctica sobre el aprendizaje de la derivada, a través de las relaciones entre pendiente y razón de cambio, conceptos que permitirán al estudiante construir un sistema de representaciones más sólido para acceder al estudio variacional. El estudio tiene el propósito de aminorar las dificultades que estos estudiantes enfrentan al realizar el estudio de las derivadas, dificultades como: la comprensión del concepto derivada, la relación entre la razón de c...

  14. Study of the effects of the irradiation on pancreatic cells `in vivo` and `in vitro`; Estudio de los efectos de la irradiacion de celulas pancreaticas `in vivo` e `in vitro`

    Rivera, E; Cricco, G; Martin, G; Cocca, C; Bergoc, R M [Buenos Aires Univ. (Argentina). Facultad de Farmacia y Bioquimica; Croci, M [Fundacion Dr. Ernesto Crescenti, Buenos Aires (Argentina)

    1999-12-31

    los mayores danos despues de la irradiacion de cuerpo entero. En roedores, dosis de 2 a 10 Gy, producen la muerte entre 10 y 30 dias post-irradiacion, siendo el pancreas uno de los organos mas tolerantes a la radiacion ionizante. En nuestro laboratorio hemos irradiado lotes de ratas Sprague-Dawley adultas, de entre 360 y 420 g de peso, con una fuente de cesio 137 de 1,1 x10{sup 16} Bq con 2, 5, 6, 7, 8, 10, 12 y 15 Gy, empleandose 8 animales por dosis. La {sup 30}DL{sub 50} resultante fue de 7,14 Gy. Todos los pancreas fueron removidos cuando los animales murieron o bien cuando los sobrevivientes fueron sacrificados a los 60 dias post-irradiacion. Especimenes de 3-5 mm fueron fijados en formol-buffer, cortes de 3-4 {mu}m fueron tenidos con hematoxilina-eosina y observados microscopicamente. A dosis de 2-5 Gy no se observaron danios histologicos. A dosis mas altas, en los animales muertos a los 4-5 dias post-irradiacion se evidencio congestion capilar y en los sobrevivientes, afluencia de linfocitos en la periferia de los islotes de Langerhans. Por otra parte, se caracterizaron `in vitro` los parametros de radiosensiblidad D{sub 0} y N de celulas malignas PANC-1 derivadas de pancreas humanos, que retienen las caracteristicas tipicas de celulas ductales diferenciadas; las celulas se mantuvieron en medio RPMI 1640 suplementado con suero fetal bovino al 10%, en estufa a 37 grados C, 5% de CO{sub 2} y humedad adecuada. Las celulas se dejaron crecer a 70-80% de confluencia y en esas condiciones se las irradio con la misma fuente de cesio 137 con: 0,5; 1; 1,5; 2; 2,5; 3; 5; 8; 10; 12; 15 y 18 Gy. Los resultados obtenidos fueron: N=2 y D{sub 0}=0,75 {+-}0,12 Gy. Los resultados obtenidos permitieron caracterizar el tipo de lesiones histologicas a altas dosis y la radiosensibilidad de las celulas PANC-1. (autor)

  15. Epitelización inducida por células troncales derivadas del tejido adiposo

    M. Meruane; S. Benítez; M. Rojas; A. Sagredo; K. Marcelain; B. Villalobos

    2014-01-01

    El tratamiento de lesiones con pérdida de tejido cutáneo ha mejorado notablemente con el advenimiento de la bioingeniería tisular. Una alternativa en desarrollo es la utilización de sustitutos dérmicos combinados con células troncales derivadas del tejido adiposo autólogo. Estudios previos nos muestran que con esta técnica es posible optimizar la angiogénesis y la síntesis de colágeno, sin embargo potenciar la epitelización es un tema pendiente por resolver. En el presente estudio evaluamos l...

  16. Determinación espectrofluorimétrica de fitohormonas derivadas del indol y del naftaleno

    Blanc García, María del Rosario

    2014-01-01

    Se realiza el estudio de las propiedades fluorescentes y la puesta a punto de metodología espectrofluorimétrica en disolución y en fase sólida para la determinación en aguas, suelos y formulaciones comerciales de las fitohormonas derivadas del indol: acido indol-3-acetico. acido indol-3-butirico, acido indol-3-propinoico y acido 5-hidroxiindol-3-acetico; y del naftaleno: acido 1-naftilacetico y 1-naftilacetamida. se lleva a cabo la determinación individual de cada una de las fitohormonas as...

  17. Hemopoietic progenitor cell identification in fetal and adult blood Célula progenitora hamatopoética - identificação em sangue fetal e de adulto

    Aixa Müller

    2008-06-01

    Full Text Available Hemopoietic progenitor cells give rise to all cellular elements of the blood and are of importance as a potential source of cells used for correction of various pathological conditions. The main objective of this study was to identify and quantitative hemopoietic progenitor cell in antenatal fetal blood, in cord blood at the time of delivery and in adult blood, using monoclonal antibodies to surface markers and flow cytometry. CD34+ cells, most of them probably representing progenitor cells, were detected in prenatal fetal blood as early as the 17th week of gestation. The proportion of these cells showed a tendency to decrease as the pregnancy progressed. Within the population of CD34+ cells, a relatively low proportion (less than 1% were negative for the surface marker CD33 or HLA-Dr, indicating a population of primitive stem cells, i.e., progenitor cells no committed to a specific lineage. On the contrary, another group coexpressed CD33 or HLA-Dr, being more mature progenitor cells already committed to differentiate along a specific lineage. The percentage of CD34+ obtained in blood of adult patients after mobilization with chemotherapeutic agents and growth factors showed an average value of 2.7± 3.1%. The percentage of CD34+ in the apheresis products of various patients varied from 0.58 to 1.48. In some cases the cells were reinfused in the patient with good results. Our findings are in agreement with previous studies suggesting that CD34+ stem cells is a heterogeneous population, with each subset having variable degree o commitment to differentiate toward a specific cell lineage.As células progenitoras hematopoéticas são as responsáveis pela produção de todos os elementos do sangue e são as potenciais fontes de células usadas para o tratamento de várias condições patológicas. O principal objetivo deste trabalho foi identificar e quantificar as células progenitoras hematopoiéticas no sangue fetal do período pré-natal, no

  18. METODOLOGÍAS EN LA ENSEÑANZA DE LA DERIVADA: URACCAN-NUEVA GUINEA

    William Oswaldo Flores López

    2013-10-01

    Full Text Available Esta investigación describe la metodología que utilizan profesores de la URACCAN -Nueva Guinea, en la enseñanza-aprendizaje de la Derivada a estudiantes de Administración de Empresas, y cómo esta metodología educativa influye en el rendimiento de la asignatura “Matemática Financiera”. Fue un estudio de caso en el que participaron dos profesores de matemática; los datos fueron obtenidos a través de un cuestionario y entrevista abierta; además, una encuesta que se le suministró al alumnado en las que se les solicitó información relacionada a los procesos metodológicos en el aula. El análisis se desarrolló en función de las redes sistémicas y los resultados muestran que existen diferencias significativas a la hora de abordar el contenido, los resultados comparativos favorecen a los estudiantes a quienes se les facilitó  clases en  la enseña de la Derivada con pertinencia al contexto social y en cuanto al profesor que aborda la Derivada desde el enfoque tradicional, se evidencian calificaciones bajas por parte del estudiantado.SummaryThis research describes the methodology that is been used by teachers of URACCAN-Nueva Guinea, in the teaching and learning of the derivatives with students of Business Administration, and how this educational methodology influences the performance of "Financial Mathematics" as a subject. In this case-study two mathematics teachers participated; the data were obtained through a questionnaire and open interviews, as well as a survey that was provided to the students in which they requested information related to the methodological processes in the classroom.  The analysis was developed based on the systemic networks and the results demonstrated significant differences in addressing the content. The comparative results favor students, due to the fact that they were provided with training classes related to the derivative with pertinence to the social context; and as for the teacher who teaches

  19. Ecuaciones en derivadas parciales con condiciones de contorno no lineales aplicaciones a la dinámica de tumores

    Morales Rodrigo, Cristian

    2009-01-01

    Esta tesis presenta tres partes: En la primera haremos un estudio teórico general de las ecuaciones elípticas en derivadas parciales con condiciones de contorno no lineales. Posteriormente, en la segunda, haremos un estudio teórico de ecuaciones elíptica

  20. Aplasia pura de serie roja post-trasplante alogeneico de células progenitoras hematopoyeticas ABO incompatible Pure red cell aplasia after ABO incompatible bone marrow transplantation

    E. Bulliorsky

    2002-12-01

    Full Text Available El trasplante alogeneico de células progenitoras hematopoyéticas (TCPH con incompatibilidad ABO entre el donante y el receptor puede en ocasiones asociarse a trastornos en la progenie eritroide desarrollada a partir de la médula ósea trasplantada, caracterizado por un funcionamiento tardío, inadecuado e incompleto de la misma. En este contexto, la aplasia pura de serie roja es la complicación más severa. Se han intentado tratamientos para la aplasia pura de serie roja post-TCPH con eritropoyetina o plasmaféresis, con relativo éxito. Algunos autores han informado también la utilización de globulina antilinfocitaria, asumiendo que dicha aplasia selectiva de la serie roja en la médula ósea trasplantada es mediada por un mecanismo inmune. En este trabajo se describe un paciente portador de una leucemia aguda en quien se realizó un TCPH alogeneico (ABO incompatible con su donante. Teniendo niveles bajos de aglutininas contra el grupo sanguíneo de la donante, desarrolló una aplasia pura de serie roja post - TCPH. La misma no mejoró con tratamiento con eritropoyetina o con un refuerzo de progenitores hematopoyéticos de sangre periférica de la misma donante (boost, resolviéndose totalmente luego de un tratamiento exitoso con globulina antilinfocitaria de origen equino.ABO incompatibility in allogeneic bone marrow transplantation may be associated with incomplete or delayed erythroid engraftment, being pure red cell aplasia (PRCA the most severe complication in this setting. Attempts for the treatment of PRCA have been made with erythropoietin or with plasmapheresis with relative success, and some authors have reported the reversibility of PRCA with antilymphocyte globulin (ALG or ATG, based on the assumption that PRCA might be immunologically mediated. We report herewith a patient with acute leukemia who developed post - BMT pure red cell aplasia. His sibling donor (sister was HLA identical and ABO incompatible, having low agglutinin

  1. Epitelización inducida por células troncales derivadas del tejido adiposo

    M. Meruane

    2014-06-01

    Full Text Available El tratamiento de lesiones con pérdida de tejido cutáneo ha mejorado notablemente con el advenimiento de la bioingeniería tisular. Una alternativa en desarrollo es la utilización de sustitutos dérmicos combinados con células troncales derivadas del tejido adiposo autólogo. Estudios previos nos muestran que con esta técnica es posible optimizar la angiogénesis y la síntesis de colágeno, sin embargo potenciar la epitelización es un tema pendiente por resolver. En el presente estudio evaluamos la progresión y diferenciación epitelial en un período de tiempo prologando. Obtuvimos las células troncales a partir del tejido adiposo (ASC de la región inguinal de 4 ratas Sprague Dawley. Cultivamos las células frescas en una matriz de Integra® durante un período total de 48 horas, y las marcamos con un vector lentiviral-GFP (proteína fluorescente verde. Posteriormente, injertamos en las mismas ratas la matriz dérmica con células troncales y un implante contralateral sin células, como control. A las 4 semanas, evaluamos el avance epitelial mediante planimetría de superficie e histología. Los resultados macroscópicos muestran que el cierre de la herida por contracción de los bordes no tiene diferencias significativas (82,63% ± 3,4% vs. 80,66% ± 3,89%; p=0,08, pero el cierre por epitelización fue significativamente mayor en el lado intervenido con ASCs (93,47% ± 5,98% vs. 79,88% ± 6,28%; p=0,0028. Todas las muestras obtuvieron tinción positiva para el anticuerpo anti-citoqueratina 34βE12 y el avance epitelial lineal cuantificado por microscopía resultó significativamente mayor en el lado con ASCs (6408 ± 275μm vs. 5375 ± 250μm; p < 0,001. Identificamos las células GFP positivas formando parte de la dermis regenerada, no así en la epidermis. En conclusión, las células troncales derivadas del tejido adiposo autólogo sembradas en una matriz de Integra® aumentan la formación epitelial significativamente

  2. Obtención y procesamiento de células progenitoras hematopoyéticas periféricas Obtention and processing of peripheral hematopoietic progenitor cells

    Jesús Diego de la Campa

    2003-12-01

    Full Text Available Se realizó un estudio descriptivo de la totalidad de las colectas de células progenitoras hematopoyéticas realizadas en el Banco de Sangre del Hospital "Hermanos Ameijeiras" desde abril del 2001 hasta abril del 2002, mediante leucoféresis. Se utilizó un equipo de flujo continuo (FRESENIUS ASTEC 204 y se empleó el programa mononucleares con el set P1Y. Se determinó peso, talla, hematócrito, hemoglobina, conteo de leucocitos y plaquetas de los donantes previo a la colecta. En el producto de la leucoféresis se analizó el conteo de leucocitos con diferencial, conteo de células CD34+/ CD45+ (mediante técnica de inmunofluorescencia en citómetro de flujo y determinación de viabilidad celular con yoduro de propidio en este mismo equipo (Facscan, Becton Dickinson. Recibieron trasplante autólogo 5 pacientes y 2 trasplantes alogénicos. Los primeros con diagnósticos de: linfoma no hodgkiniano (3, enfermedad de Hodgkin (1, artritis reumatoidea (1; y los segundos afectados de leucemia mieloide crónica (1 y linfoma no hodgkiniano (1 ; todos ellos atendidos en el Servicio de Hematología de nuestro centro. La media del conteo de células CD34+ por cada leucoféresis para trasplante autólogo fue 2,4 x 106 Kg y en el alogénico 2,96 x 106 Kg . Los resultados evidencian que mediante el ajuste del volumen de los ciclos, la velocidad centrífuga, el volumen de rebosado y el volumen celular, se obtuvo un conteo de células precursoras hematopoyéticas en la colecta similar a lo reportado por otros autores, lo que garantiza que el producto transfundido cuente con la celularidad necesaria para repoblar la médula ósea, luego que el paciente sea tratado con altas dosis de terapia inmunosupresora y/o radiacionesA descriptive study of all the collections of hematopoietic progenitor cells obtained by leukophoresis at the Blood Bank of "Hermanos Ameijeiras" Hospital from April, 2001, to April, 2002, was conducted. A continual flow equipment (FRESENIUS

  3. La contaminación atmosférica derivada de las aglomeraciones urbanas y otras causas

    Almenar-Muñoz, Mercedes

    2017-01-01

    [ES] Se analiza el incumplimiento de varios Estados miembros de los niveles máximos permitidos por la UE respecto a la calidad del aire y propone medidas urgentes para paliar este grave problema ambiental. También se aborda el tratamiento de la contaminación atmosférica en el planeamiento urbanístico. Almenar-Muñoz, M. (2017). La contaminación atmosférica derivada de las aglomeraciones urbanas y otras causas. Actualidad Jurídica Ambiental. (67):1-10. http://hdl.handle.net/10251...

  4. Propiedades psicométricas del instrumento prácticas derivadas del aprendizaje social del profesorado

    Ana Karen Hurtado Espinoza

    2017-01-01

    Full Text Available El objetivo fue establecer las propiedades psicométricas de un instrumento para medir en qué grado las acciones derivadas de la socialización con estudiantes, especialistas educativos-­‐disciplinares y pares académicos contribuyen en la formación docente de los profesores universitarios. Se seleccionó de forma no probabilística a 196 profesores que se encuentran adscritos a una institución pública del Sur de Sonora, de los cuales 100 son mujeres (M edad=36.5, DE=9.4 años, y 96 hombres (M edad=42.2, DE=11.7 años. Los resultados reflejan que la escala tiene confiabilidad medida por Alfa de Cronbach de .94; en el análisis factorial exploratorio se utilizó el método de ejes principales y rotación Oblimin, se obtuvo una solución de tres factores que explican el 56.46% de la varianza de los puntajes. En conclusión, el instrumento presenta evidencias de confiabilidad y validez. Además, es una escala potencial para medir las prácticas derivadas del aprendizaje social que contribuyen a la formación docente de los profesores universitarios.

  5. Controle de esterilidade de produtos de células progenitoras hematopoéticas do sangue periférico Sterility control of hematopoietic progenitor cells from peripheral blood products

    Igor D. Almeida

    2010-02-01

    Full Text Available A taxa de contaminação microbiana dos produtos de células progenitoras hematopoéticas do sangue periférico é baixa. Neste estudo pesquisou-se a prevalência de hemoculturas positivas em células progenitoras hematopoéticas do sangue periférico (CPHSP no Serviço de Hemoterapia do Hospital de Clínicas de Porto Alegre. Do total de 618 coletas realizadas no período de 2000 a 2007, 26 (4,2% apresentaram contaminação por bactérias. O Staphylococcus coagulase-negativo foi predominantemente isolado nas hemoculturas. A antibioticoterapia pré e pós-infusão foi estabelecida de acordo com o microorganismo e seu antibiograma, sendo que, em cinco das doze infusões contaminadas realizadas, não foram administrados antimicrobianos profilaticamente. Episódios febris foram observados em sete pacientes (58%, enquanto cinco (42% não apresentaram febre. Das doze infusões contaminadas realizadas, seis (50% apresentaram hemocultura pós-descongelamento positivas, enquanto as restantes (50% foram negativas. Isto se deve às propriedades bactericidas do DMSO, de células fagocitose-ativas e de temperaturas muito baixas atingidas na criopreservação. Autores têm relatado sucesso neste procedimento após a infusão desses produtos contaminados com o mínimo de consequências clínicas.The rate of microbial contamination of hematopoietic progenitor cell products from peripheral blood is low. In this study, we investigated the prevalence of positive blood cultures of hematopoietic progenitor cells from peripheral blood in a hemotherapy service. Of a total of 618 samples taken during the period from 2000 to 2007, 26 (4.2% were contaminated by bacteria. Staphylococcus coagulase-negative was the predominant bacterium isolated in blood cultures. Pre- and post-infusion antibiotic therapy was established depending on the microorganism and antibiogram, whereas in five out of twelve contaminated infusions, no antibiotics were administered prophylactically

  6. PROPUESTA METODOLÓGICA EN LA APLICACIÓN DE LA DERIVADA EN INGENIERÍA AGROFORESTAL, II SEMESTRE 2013

    Ernesto Vanegas Sevilla

    2016-05-01

    Full Text Available Esta investigación ha evidenciado la importancia que tienen las estrategias metodológicas en el proceso educativo en las aplicaciones de las derivadas en la carrera de Ingeniería Agroforestal, pretendiendo que los discentes desarrollen autonomía para enriquecer su conocimiento y un aprendizaje significativo, forjar consciencia sobre la importancia que tiene la implementación de los softwares en las aplicaciones matemáticas. El enfoque mixto permitió enriquecer los datos cuantitativos con la información cualitativa admitiendo la recolección, análisis y vinculación de los indicadores. La población fue conformada por 58 estudiantes de Ingeniería Agroforestal  de los recintos de URACCAN Bluefields y Siuna (Las Minas, considerando como muestra a toda población, debido a que es muy pequeña al aplicar la fórmula triola para el cálculo de la muestra de una población finita con un margen de error del 1%  y un nivel de confianza del 95%. El estudio determinó que la mayor dificultad es que los  estudiantes no traen un dominio pleno de la Matemática (álgebra y geometría, razón por cual se les dificulta la comprensión y resolución de las derivadas. Summary This research has demonstrated the importance of methodological strategies in the educational process related to the applications of by-product in the career of Agroforestry Engineering, with the pretension that students develop autonomy to enrich their knowledge and achieve meaningful learning, and also to build awareness about the importance of the implementation of software in the mathematics applications. The mixed approach permitted to enrich the quantitative data with qualitative information admitting the collection, analysis and link with the indicators. The population was made up of 58 students of Agroforestry Engineering from URACCAN (Bluefields and Siuna Campus (Las Minas, considering the entire population as sample, due to the fact that it’s very small when applying

  7. El daño como elemento fundamental para la exigencia de la responsabilidad civil derivada del delito

    Iracema Gálvez Puebla

    2014-06-01

    Full Text Available La perspectiva estructural que se sigue con la investigación, parte de sugerentes cuestiones sobre el daño como eje central dentro de la responsabilidad civil derivada del delito; así como de la naturaleza y funciones de la obligación civil ex delito, teniendo en cuenta tres hipótesis fun- damentales que abordan tanto su naturaleza puramente civil, hasta valorarla como perteneciente a la materia penal, concluyendo con el análisis de la esencia mixta de la institución, en base a fundamentos políticos- sociales, de la imposición sancionadora que logra la satisfacción del per- judicado- acreedor, al venir impuesta por el ordenamiento jurídico frente a un daño que con- firma la interrelación de los elementos sobre la causa efficiens y la causa finalis de la obligación específica, que parte de una relación jurídica funcionalmente organizada.

  8. Importância de polimorfismos de genes reguladores de citocinas em transplantes de células progenitoras hematopoiéticas Importance of regulatory cytokine gene polymorphisms in hematopoietic stem cell transplantation

    Jeane Eliete Laguila Visentainer

    2008-12-01

    Full Text Available A compatibilidade genética HLA entre doador e receptor é um fator importante para o sucesso do transplante de células progenitoras hematopoiéticas (TCPH. No entanto, outros genes não-HLA estão sendo investigados em relação ao seu papel na incidência e gravidade da doença do enxerto contra o hospedeiro e na sobrevida, por modularem a intensidade da inflamação e os danos teciduais. Estes genes, não-HLA, incluem os genes de citocinas com polimorfismos dentro das seqüências 5' ou 3' regulatórias dos genes. Os polimorfismos ou microssatélites podem alterar a ligação dos fatores de transcrição aos sítios dentro dos genes promotores e a quantidade de citocina produzida. Este estudo revisa o papel potencial destes polimorfismos genéticos relativos às citocinas em prever o curso do TCPH.HLA genetic matching of donor and recipient is an important requirement for optimizing outcome following hematopoietic stem cell transplantation (HSCT. However, other non-HLA genes are being investigated for their role in graft-versus-host disease incidence and severity and in survival, by modulating the intensity of inflammation and tissue injury. These non-HLA-encoded genes include cytokine genes with polymorphisms within the 5' or 3' regulatory sequences of the genes. The polymorphisms or microsatellites may alter the transcription factor binding sites within the gene promoters and the amount of cytokine produced. This chapter summarizes the potential role of these genetic polymorphisms regarding the cytokines in predicting outcome of HSCT.

  9. Poliuretana derivada de óleos vegetais exposta ao intemperismo artificial Polyurethane derived from vegetal oil exposed to artificial weathering

    Alessandra E. F. S. Almeida

    2006-01-01

    Full Text Available Foram obtidas as propriedades mecânicas e viscoelásticas da poliuretana derivada do óleo de mamona após sua exposição ao intemperismo artificial, a fim de avaliar a aplicabilidade deste material como revestimento polimérico para substratos de concreto na Construção Civil. Os procedimentos experimentais foram realizados em conformidade com a ASTM G 53 for "Operating Light and Water Exposure Apparatus (Fluorescent UV - Condensation Type for Exposure of Nonmetallic Materials"[1]. O ensaio para a caracterização mecânica dos corpos-de-prova após exposição ao intemperismo artificial foi realizado conforme a norma ASTM D 638M-96 "Standard Test Method for Tensile Properties of Plastics (Metric"[2]. Foi empregado o método de análise dinâmico-mecânica para a obtenção das propriedades viscoelásticas da poliuretana vegetal. Os resultados mostraram que a exposição ao intemperismo artificial não ocasionou mudanças significativas nas propriedades do revestimento polimérico para o tempo de exposição estudado.The mechanical and viscoelastic properties of polyurethane derived from castor oil were obtained after being exposed to artificial weathering with the purpose of evaluating their applicability as polymeric coatings on concrete substrate for Civil Construction. The procedures followed the ASTM G53 for "Operating Light and Water Exposure Apparatus (Fluorescent UV - Condensation Type for Exposure of Nonmetallic Materials"[1]. Mechanical properties were obtained by means of the ASTM D 638M-96 "Standard Test Method for Tensile Properties of Plastics (Metric"[2]. Furthermore, a Dynamic Mechanical Analysis (DMA was carried out in order to study the viscoelastic properties of polyurethane. The results showed that the properties were altered slightly considering the time studied.

  10. Revisión sistemática: células madre derivadas del tejido adiposo, utilidad en lipoatrofia facial

    M.D. Cruz-Sánchez

    2014-06-01

    Full Text Available El objetivo de la presente revisión sistemática es determinar si los lipoinjertos enriquecidos con células madre derivadas del tejido adiposo son superiores a los injertos de tejido graso convencionales en el tratamiento de la lipoatrofia facial. Realizamos una búsqueda sistemática de publicaciones en las bases de datos: MEDLINE, SCOPUS, OVID SP, SCIELO y EMBASE y posteriormente, una valoración basada en criterios actuales de medicina basada en la evidencia de las publicaciones encontradas por dos revisores independientes; las discrepancias en el análisis se resolvieron por acuerdo. Los criterios de inclusión fueron: ensayos clínicos aleatorizados, series clínicas y reportes de casos en humanos, excluyendo los ensayos en animales. Encontramos 6 publicaciones que cumplían con los criterios previamente mencionados. Entre éstas se incluyeron 2 ensayos clínicos aleatorizados controlados que recogían la superioridad de los lipoinjertos enriquecidos con células madre derivadas del tejido adiposo en el tratamiento de la lipoatrofia facial en términos de resistencia a la reabsorción (preservación del volumen y menor necesidad de nuevos lipoinjertos, en comparación con los lipoinjertos convencionales. Concluimos diciendo que existen publicaciones con buenos niveles de evidencia que sugieren que los lipoinjertos enriquecidos con células madre derivadas del tejido adiposo son superiores a los lipoinjertos convencionales en el tratamiento de la lipoatrofia facial. No obstante, son estudios de reciente publicación y aún es necesario tener seguimientos a más largo plazo y con mayor número de pacientes para mejorar los ya buenos niveles de evidencia disponibles.

  11. Mecanismos moleculares involucrados en la diferenciación neuronal de células madre mesenquimales humanas derivadas de tejido adiposo

    Cardozo, Alejandra Johana

    2014-01-01

    Cardozo, A. J. (2015). Mecanismos moleculares involucrados en la diferenciación neuronal de células madre mesenquimales humanas derivadas de tejido adiposo (Tesis de Doctorado). Universidad Nacional de Quilmes, Bernal, Argentina. Como el sistema nervioso tiene una capacidad limitada de autorreparación, y la neurogénesis en el adulto está restringida a ciertas regiones del cerebro, existe un gran interés en la posibilidad de reparar el sistema nervioso a través de la utilización de técnica...

  12. Composición química de cúmulos globulares galácticos: metalicidades derivadas a partir de fotometría de Washington

    Torres, M. C.; Clariá, J. J.

    Se presentan temperaturas efectivas y abundancias de 183 gigantes rojas en 7 cúmulos globulares galácticos, derivadas a partir de fotometría de Washington realizada en Cerro Tololo. Las metalicidades provienen de una calibración que tiene en cuenta la disminución de sensibilidad de algunos índices con la temperatura. Los valores medios de [Fe/H] obtenidos oscilan entre -1.2 y -2.15, con errores típicos del orden de 0.2 salvo un par de excepciones. Teniendo en cuenta que el índice (C-T1) es significativamente más sensible a la metalicidad que (V-I), se presenta una calibración de abundancia basada en el color (C-T1)o de la rama gigante roja para una determinada magnitud absoluta M(T1). Las abundancias derivadas confirman en general la escala de Zinn (1985, ApJ, 293, 424).

  13. Comparación de anomalías de gravedad derivadas de altimetría satelital con datos de gravedad marina en el margen continental Argentino

    Ana Carolina Pedraza De Marchi

    Full Text Available En este trabajo se comparan grillas de anomalías de gravedad derivadas de misiones de altimetría satelital con anomalías de gravedad marina a partir de datos de cruceros en el margen continental argentino y zona oceánica adyacente. Se analizan las diferencias entre estas fuentes de datos, ya que es de esperar que éstas sean significativas en zonas costeras o de gradiente horizontal de gravedad abrupto como en el talud continental; se trata de identificar y delimitar dichas zonas. Asimismo se analizan los datos de barco de distintas campañas realizadas en épocas diferentes para organizarlos en una base de datos común, como parte de un proceso de compilación en el que se crearán versiones mejoradas con nuevas correcciones en la medida en que se incorporen más datos en el futuro. Se investiga cuál de las grillas de gravedad derivada de altimetría satelital presenta mejor ajuste con la compilación marina a fin de caracterizarla como la recomendable para su uso en posteriores aplicaciones. Se presentan aquí los resultados de la primera etapa completada en función del alcance los objetivos mencionados.

  14. Autologous stem cell transplantation for aggressive non-Hodgkin's lymphomas Transplante autólogo de células progenitoras para pacientes com linfomas não Hodgkin agressivos

    G. Santini

    2002-04-01

    Full Text Available Autologous stem cell transplantation (ASCT has been seen to overcome resistance, allowing an increase in the dose of available drugs and radiotherapy. Initially used after first-line for relapsed or refractory non-Hodgkin's lymphomas (NHL, ASCT has since been used in more favourable clinical conditions such as partial remission (PR, first completeremission, and as front-line therapy following chemotherapy. High-dose chemotherapy and autologous stem-cell transplantation has now became the standard care for eligible patients with recurrent, chemosensitive aggressive NHL. Primary refractory patients and resistant relapse are not good indications and should be considered a group eligible for phase II studies. There may also be a role in patients with partially responsive disease. However new and larger randomised studies are needed to clarify this question. A challenge for lymphoma management is the evaluation of the role of high-dose therapy and ASCT as an initial treatment in aggressive NHL, identifying patients who will not be cured with standard therapy. A series of concurrent or retrospective analysis would indicate so-called "higher-risk patients", as defined by the IPI, as potential targets for intensified therapy. However, according to published data, the problem remains open to debate. Larger, randomised studies are necessary and welcome and this should be considered a high priority.O transplante autólogo de célula progenitora ou medula óssea (ATMO tem demonstrado capacidade de superar resistência tumoral através da elevação da intensidade de dose de drogas disponíveis e radioterapia. ATMO foi inicialmente utilizado em LNH após recidiva em primeira linha ou refratários. ATMO tem demonstrado maior utilidade em condições clínicas mais favoráveis como na remissão parcial (RP, primeira remissão completa (RC e como primeira linha após quimioterapia. Quimioterapia de alta dose e ATMO se tornaram a terapêutica standard para

  15. Allogeneic hematopoietic stem cell transplantation for primary myelodysplastic syndrome Transplante alogênico de células progenitoras hematopoiéticas para síndrome mielodisplásica primária

    Carlos R. Medeiros

    2004-01-01

    Full Text Available Characteristics and outcomes of 52 patients with myelodysplastic syndrome (MDS who underwent allogeneic hematopoietic stem cell transplantation (allo-HSCT were analyzed. Median age was 30 years (range 2-61 years and median time from diagnosis to allo-HSCT was 10 months (range 1-161 months. Thirty-six patients had advanced MDS or acute myeloid leukemia following MDS at transplant. Conditioning with busulfan and cyclophosphamide was administered to 73% of patients, and the median value of graft dose was 2.595 x 10(8 of total nucleated cells/kg. Overall survival and disease free survival at 4 years were 36% and 33%, respectively. Nineteen patients were alive, with a median follow-up of 3.8 years. Twelve patients relapsed and only one is alive, after donor lymphocyte infusion. Interval II occurred in 19 patients. Donor type (identical related versus non-related/partially matched related influenced the incidence of acute GVHD (P = 0.03. Eleven patients developed chronic GVHD and previous acute GVHD was a risk factor (P = 0.03. Thirty-three patients died, 22 (67% secondary to transplant-related complications. Patients with MDS should undergo allo-HSCT earlier, mainly if they have a compatible donor and are young.Características e resultados de 52 pacientes com síndrome mielodisplásica (MDS submetidos a transplante alogênico de células progenitoras hematopoiéticas (TCPH foram analisados. A idade mediana foi de 30 anos (variação de 2-61 anos e o tempo mediano entre o diagnóstico e transplante foi de dez meses (variação de 1-161 meses. Trinta e seis pacientes tinham MDS avançada ou leucemia mielóide aguda secundária a MDS ao transplante. O condicionamento com busulfano e ciclo­fosfamida foi recebido por 73% dos pacientes, e a dose celular mediana do enxerto foi de 2.56 x 10(8 células nucleadas/kg. A sobrevida global e a sobrevida livre de doença aos quatro anos foi de 36% e 33%, respectivamente. Dezenove pacientes estavam vivos, com um

  16. Autografting of peripheral-blood progenitor cells early in chronic myeloid Leukemia Transplante autólogo de células progenitoras em fase crônica precoce da Leucemia mielóide crônica

    Paulo V. B. Carvalho

    2004-12-01

    Full Text Available The role of peripheral-blood progenitor cell (PBPC transplantation as a treatment for chronic myeloid leukemia (CML patients remains uncertain. We presented herein 11 CML patients treated with autografting of PBPC in early chronic phase followed by interferon-alpha (IFN-alpha. Bone marrow samples obtained at diagnosis and during follow-up after autografting as well as leukapheresis products were analyzed by cytogenetics, fluorescence in situ hybridization (FISH and reverse transcriptase-polymerase chain reaction (RT-PCR. The median follow-up of patients after autografting was 22 months (range: 1-49. Two treatment-related deaths occurred in patients enrolled in the study. Eight out of 9 (88.9% and 7 out of 9 (77.8% patients achieved hematologic and cytogenetic responses, respectively. Molecular cytogenetic and molecular responses were seen in all 7 patients analyzed (100.0% and in one single patient (11.1%, respectively. The median percentages of Ph+ (78.0% metaphases obtained after 6 months of autografting was lower than those obtained at diagnosis (100.0%, P=0.04. The median percentages of FISH+ nuclei obtained at 3 (4.0%, 6 (7.3% and 9 (14.7% months after autografting were also lower than that obtained at diagnosis (82.5%; P=0.002; P=0.003; P=0.030, respectively. At the end of the study, 9 patients (81.8% were alive in chronic phase, 4 of them presenting hematologic, cytogenetic and molecular cytogenetic responses. We conclude that autografting performed with PBPC in early chronic phase of CML followed by IFN-alpha results in lower numbers of Ph+ and FISH+ cells in bone marrow.O papel do transplante de célula progenitora periférica (CPP como tratamento de pacientes com leucemia mielóide crônica (LMC permanece incerto. Nós apresentamos neste estudo 11 pacientes com LMC tratados com o transplante autólogo (TMO-auto de CPP durante a fase crônica precoce, seguido de interferon-alfalfa (IFN-alfa. Amostras de medula óssea, obtidas ao diagn

  17. EL PROCESO DE ENSEÑANZA-APRENDIZAJE DE LA DERIVADA EN LA CARRERA DE COMERCIO EXTERIOR Y NEGOCIOS INTERNACIONALES DE LA UNIVERSIDAD LAICA ELOY ALFARO DE MANABÍ

    Miguel Escalona-Reyes

    2017-01-01

    Full Text Available La Educación Superior en Ecuador se encuentra en un proceso de perfeccionamiento,  debido a la necesaria transformación que debe asumir para asumir un nuevo redimensionamiento de la misión de la universidad contemporánea ante los retos del nuevo siglo. Uno de los cambios fundamentales radica en el perfeccionamiento del currículo de las carreras, y con ello de los programas de las diferentes materias; para el caso del estudio de la Matemática, no puede desvincularse su estudio del contexto social y el proyecto social en que se desarrolla el proceso pedagógico de los profesionales en formación, de la misma manera que no se puede concebir como algo abstracto y general, debiendo conjugarse con los objetivos y con las tareas que dimanan de los resultados parciales del espacio y del tiempo en el que transcurren. Uno de los temas de esta asignatura, esenciales para el estudiante de la carrera de Comercio Exterior y Negocios Internacionales, es la derivada, ya que permite aplicar dicho conocimiento en la resolución de ejercicios y problemas que son afín con la vida profesional del estudiante. No obstante, se ha constatado varias insuficiencias en el proceso de enseñanza aprendizaje de estos contenidos en esta carrera; motivo por el cual se realiza esta investigación, donde se presenta una Alternativa Metodológica para favorecer dicho proceso.PALABRAS CLAVE: Didáctica de la Matemática; Derivada; Formación Profesional.THE TEACHING-LEARNING PROCESS OF DERIVATIVES IN THE CARRER OF FOREIGN TRADE AND INTERNATIONAL BUSINESS FROM THE UNIVERSIDAD LAICA ELOY ALFARO DE MANABÍABSTRACTHigher Education in Ecuador is involved in a process of improvement, due to the necessary transformation which must be followed to assume a new downsizing of the mission of nowadays university in the challenges of the new century. One of the main changes lies in the improvement of the curriculum of courses, and the syllabus in different subjects; respected to the case

  18. Estudio retrospectivo de la aplicación de la amplificación génica cualitativa en muestras biológicas para el seguimiento de la toxoplasmosis en pacientes pediátricos receptores de trasplante de células progenitoras hematopoyéticas

    Mónica G Nigro

    Full Text Available La toxoplasmosis es una infección oportunista causada por el parásito Toxoplasma gondii; su infección es grave y de difícil diagnóstico en pacientes que reciben un trasplante alogénico de células progenitoras hematopoyéticas (TCPH. En el Hospital de Pediatría S.A.M.I.C. "Profesor Dr. Juan P. Garrahan"� se realizó la vigilancia postrasplante de 12 pacientes receptores de TCPH mediante la técnica de PCR cualitativa. La necesidad de seguimiento de estos pacientes fue definida por el antecedente de serología positiva para toxoplasmosis en el donante o receptor y ante la imposibilidad de iniciar el uso profiláctico de trimetoprima-sulfametoxazol a causa de la condición hematológica. Dos pacientes presentaron signos de enfermedad por T. gondii con resultado de PCR positivo y recibieron tratamiento con pirimetamina-clindamicina. En otros dos, la toxoplasmosis fue causa de muerte y hallazgo de autopsia, con resultado de PCR negativo. Cuatro pacientes recibieron tratamiento contra toxoplasmosis por la detección de una PCR positiva, sin manifestaciones clínicas. En los cuatro pacientes restantes no se detectaron signos de enfermedad por toxoplasmosis, con resultados de PCR negativos durante el seguimiento. La técnica de PCR cualitativa demostró ser útil para detectar la reactivación de la toxoplasmosis en receptores de TCPH, pero tiene limitaciones para el seguimiento y la toma de decisiones clínicas en pacientes con PCR positiva que persiste en el tiempo y manifestaciones de toxicidad por el tratamiento.

  19. Cuestiones sobre el derecho al trabajo derivadas de la reforma laboral de 2012 : perspectiva constitucional = The right to work under the labour reform of 2012: a constitutional approach

    Rafael Naranjo De La Cruz

    2014-01-01

    Full Text Available La reforma laboral de 2012 ha suscitado importantes cuestiones acerca del régimen jurídico del derecho al trabajo. Así, en este artículo se sostiene que la introducción de una modalidad contractual que concede al empresario la potestad de resolver libremente el contrato laboral durante el primer año supone, ya sea concebido este plazo como periodo de prueba o como medio para el fomento de un empleo estable, una vulneración del derecho del trabajador a la estabilidad en el empleo, reconocido como manifestación del art. 35 CE por el Tribunal Constitucional. También se analiza desde una perspectiva constitucional el régimen jurídico del despido improcedente, que consideramos incoherente con la condición del derecho al trabajo como derecho fundamental. Finalmente, sostenemos que la configuración legal dada a las causas del despido colectivo no puede llegar a impedir su control judicial desde la perspectiva del principio de proporcionalidad, ya que este se presenta como una exigencia derivada del propio derecho al trabajo y del derecho a la tutela judicial efectiva. The 2012 labour reform has raised important questions regarding regulation of the right to work. This paper proposes that the employer’s right to terminate a contract in support of entrepreneurs during its first year, interpreted either as a probationary period or as a measure for the promotion of stable employment, violates the constitutional right of every worker to stability in employment (Article 35 of the Constitution. Furthermore, regulation of unfair dismissal is analyzed from a constitutional perspective to reach the conclusion that it is incompatible with the constitutional right to work. Finally, it is argued that the regulation of the causes of collective dismissal cannot prevent the Constitutional Court from reviewing whether the principle of proportionality has been observed, since this is a requirement arising from the constitutional rights to work and to an

  20. Emprego experimental da poliuretana derivada de óleo de mamona (Ricinus communis L: em implantes lamelares, interlamelares e penetrantes na córnea de coelhos

    Adriana Morales

    2005-02-01

    Full Text Available Há muito que se estudam métodos e materiais reparadores de córnea, em busca de uma melhor reposição tecidual e, principalmente, manutenção ou recuperação da visão. A pesquisa de novos biomateriais tem permitido produzir próteses capazes de desempenhar a função requerida, sem reação importante. Conhecendo-se os bons resultados obtidos com a utilização da poliuretana vegetal derivada de óleo de mamona (Ricinus communis L. em vários procedimentos, estudou-se sua implantação, em forma de membrana, na córnea, objetivando oferecer novo material para a reparação de lesões corneanas e a confecção de ceratopróteses biologicamente inertes. Utilizaram-se 28 coelhos, divididos em dois grupos (G1 e G2 e estes em subgrupos para avaliações de implantes lamelares e interlamelares aos 2, 7, 15, 30, 60 e 120 dias, e implantes penetrantes, aos 2, 7, 15, 30 e 60 dias de pós-operatório. Estudaram-se parâmetros como neovascularização, inflamação, transparência de córneas e implantes, bem como a aderência e viabilidade destes, através de exames oculares, e histopatológicos à microscopia óptica. Observou-se reação inflamatória branda em todos os períodos. Os implantes lamelares e penetrantes permitiram reparação da córnea e manutenção da integridade dos globos oculares, embora sofressem deiscência entre 5 e 28 dias de pós-operatório. Concluiu-se pela boa biocompatibilidade do material e pela possibilidade de empregar-se o polímero na reparação corneana e, possivelmente, em ceratopróteses.

  1. Determinação de cumarina em extrato fluido e tintura de guaco por espectrofotometria derivada de primeira ordem Determination of coumarin in fluid extract and tinture of "guaco" by first derivative spectrophotometry

    Adriana de Carvalho Osório

    2004-12-01

    Full Text Available O objetivo do trabalho foi desenvolver um método de doseamento de cumarina (1,2-benzopirano em extrato fluido e tintura de guaco (Mikania glomerata Sprengel. O método desenvolvido foi por espectrofotometria derivada de primeira ordem, que se mostrou preciso, exato, reprodutível e de fácil execução.The objective of this work was to develop a method for coumarin(1,2-benzopyran dosage in fluid extract and tinture of "guaco" (Mikania glomerata Sprengel. First derivative spectrophotometry was developed and proved to be accurate, exact, reprodutive and of easy execution.

  2. Modelos animales y células derivadas para su uso en la determinación de compuestos útiles en el tratamiento de linfomas de células T

    Bustelo, Xosé R.; Ruiz Macías, Sergio; Santos de Dios, Eugenio

    2008-01-01

    Modelos animales y células derivadas para su uso en la determinación de compuestos útiles en el tratamiento de linfomas de células T. La presente invención se encuadra dentro del campo de la biotecnología. Se refiere a un método para evaluar si un compuesto es efectivo en la prevención y/o tratamiento de una enfermedad asociada a linfomas de células T.

  3. Modelo de cuantificación de las emisiones de CO2 producidas en edificación derivadas de los recursos materiales consumidos en su ejecución

    Olivares, M.

    2012-09-01

    Full Text Available Research in this paper focuses on the generation of a model to quantify CO2 emissions in the implementation of a typical building block for affordable residential housing, derived from the manufacturing process of the materials used in its construction. The identification and quantification of building materials consumed, will reveal the environmental impact of producing the type defined by one of the indicators most relevant environmental impact associated with weight per m2 of construction, such as CO2 emissions resulting from manufacturing process of the construction materials used in its implementation. Its practical application to a set of ten projects located in Seville implementation, will provide conclusive data on the quantification of CO2 emissions in its implementation by identifying the greatest environmental impact.La investigación realizada en el presente trabajo plantea la generación de un modelo de cuantificación de las emisiones de CO2 producidas en la ejecución del modelo constructivo habitual definido como el bloque residencial destinado a viviendas de protección oficial, derivadas del proceso de fabricación de los recursos materiales empleados en su ejecución. La identificación y cuantificación de los materiales de construcción consumidos, permitirá conocer el impacto medioambiental que produce la tipología definida, a través de uno de los indicadores de impacto ambiental más relevantes asociados al peso por m2 de construcción, como son las emisiones de CO2 derivadas del proceso de fabricación de los materiales de construcción empleados en su ejecución. Su aplicación práctica a un conjunto de diez proyectos de ejecución ubicados en Sevilla, proporcionará datos concluyentes sobre la cuantificación de las emisiones de CO2 producidas en su ejecución, identificando los de mayor impacto ambiental.

  4. Effects of Radiation on Germ Cells of Insects: Dominant Lethals, Gamete Inactivation and Gonial-Cell Killing; Effets des rayonnements sur les cellules germinales des insectes: letalite dominante, inactivation des gametes et destruction des cellules des gonades; Vozdejstvie radiatsii na polovye kletki nasekomykh: dominantnye letali, inaktivatsiya gamet i umershchvlenie polovykh kletok; Efectos de las radiaciones sobre las celulas germinales de los insectos: elementos letales dominantes, inactivacion de los gametos y exterminacion de las celulas gonadicas

    Von Borstel, R. C. [Biology Division, Oak Ridge National Laboratory, Oak Ridge, TN (United States)

    1963-09-15

    en calculant la viabilite des gametes, au moyen d'experiences comparatives avec des populations non irradiees ainsi que par l'examen histologique des gonades. (author) [Spanish] Las radiaciones y los productos quimicos mutagenos pueden matar las celulas de modos diversos, a saber: mediante la induccion de uno o varios tipos de elementos letales dominantes, por inactivacion directa de una funcion, como la produccion de esperma, y por procedimientos geneticamente indefinibles de exterminacion que pueden o no estar relacionados con la letalidad dominante intrinseca. Por otra parte, los productos quimicos mutagenos parecen provocar un curioso aumento de la capacidad fertilizante de la esperma. La radiosensibilidad varia segun las diferentes etapas de la oogenesis y de la espermatogenesis, y las celulas pasan por fases en que dicha sensibilidad llega a ser 50 veces superior o inferior que en otras. En la medida en que distintas especies de dipteros, himenopteros y coleopteros son comparables, puede observarse una sorprendente analogia en la radiosensibilidad, tanto segun las etapas como segun las dosis. La radiosensibilidad de las celulas germinales del gusano de seda Bombyx mori (Lepidopt. ) parece similar en muchos aspectos a la de los insectos de otros ordenes, pero en cambio hay grandes diferencias en cuanto a los tipos de elementos letales dominantes que en el pueden inducirse. Las especies con mecanismos geneticos atipicos (por ejemplo, el sistema lecanoideo del Planococcus citri (Hemipt. ; Coccidae) constituyen casos especiales y su radiosensibilidad varia considerablemente en relacion con la de otras especies. Para la lucha contra los insectos por el metodo de irradiacion de los machos, la creacion de un elemento letal dominante ofrece en las especies donde las copulas son multiples las mismas ventajas que en las especies que copulan solo iva vez. La inactivacion de la esperma y la exterminacion de las celulas gonadicas pueden considerarse como casos de autentica

  5. derivadas de la investigación

    Ángel Vázquez-Alonso

    2007-01-01

    Full Text Available El currículo, los materiales didácticos y las prácticas de enseñanza y aprendizaje de la educación científica tradicional abusan de los dos factores epistémicos sugeridos por el positivismo lógico, la referencia empírica y el razonamiento lógico, junto con su epítome el lenguaje matemático, que sostienen la verdad y la objetividad como valores esenciales de la ciencia. La consecuencia más notable de esta abusiva orientación positivista es la exclusión, implícita y explícita, de otros valores incompatibles con ellos (factores sociales, culturales o afectivos, tildados como impropios o acientíficos por oponerse a la objetividad de la ciencia, aunque sean didácticamente valiosos. Sin embargo, los análisis y las críticas filosóficas, sociológicas e históricas sobre el positivismo lógico han enfatizado la presencia de los aspectos afectivos, actitudinales y emocionales, entre otros más, en la construcción del conocimiento científico. Este estudio argumenta la necesidad de los factores actitudinales y afectivos como resortes imprescindibles para la didáctica de la ciencia. En esta segunda parte se exponen pruebas empíricas provenientes de la investigación específica sobre las variables afectivas relativas a la ciencia y la tecnología (actitudes hacia la ciencia escolar, creencias sobre naturaleza de la ciencia, imagen pública de la ciencia, actitudes hacia el medio ambiente, vocaciones científicas, etc..

  6. Estructura genética del caballo de pura raza árabe español y su influencia en razas derivadas: aplicación de nuevas metodologías en el cálculo del tamaño efectivo

    Cervantes Navarro, Isabel

    2008-01-01

    Durante el desarrollo del estudio se ha analizado la estructura genética del caballo de Pura Raza Árabe y de sus razas derivadas y se ha puesto a punto una nueva metodología de estimación del tamaño efectivo, aplicándose en poblaciones simuladas y reales. Se observó una reducida variabilidad genética en el caballo de Pura Raza Árabe Español, ocasionada por el desequilibrio en la utilización de los reproductores y el cuello de botella acaecido durante la Guerra Civil. Este hecho está compensán...

  7. Nucleic Acids and Protein Metabolism of Bone Marrow Cells Studied by Means of Tritiumlabelled Precursors; Etude du Metabolisme des Acides Nucleiques et des Proteines dans les Cellules de la Moelle Osseuse, a l'Aide de Precurseurs Trities; 0418 0437 0443 0414 ; Estudio con Ayuda de Precursores Tritiados del Metabolismo de los acidos Nucleicos y de las Proteinas en las Celulas de la Medula Osea;

    Gavosto, F. [Istituto di Clinica Medica Generale e Centro di Studi Fisico-Biologici, Universita de Turin, Turin (Italy)

    1962-02-15

    . L'auteur examine ensuite la diminution et la dissociation du metabolisme de l'ARN et des proteines, dans les cellules de sujets atteints de leucemie aiguee, par rapport aux anomalies bien connues que presente le processus de maturation de ces cellules. (author) [Spanish] El autor examina las ventajas que presenta el empleo de los compuestos marcados con tritio en la tecnica autorradiografica. En efecto, los electrones emitidos por el tritio tienen una energia maxima de 0,018 MeV, que corresponde, aproximadamente, a un alcance de 1 miera en una emulsion fotografica y permiten, por lo tanto, lograr el maximo poder de resolucion al nivel celular y subcelular. Ello es particularmente util para estudiar fenomenos metabolicos en tejidos que se componen, como en el caso de la medula osea, de celulas de varios tipos en diversos estados de diferenciacion. Esta tecnica se ha aplicado al estudio del metabolismo de los acidos nucleicos y de las proteinas en las celulas normales y leucemicas de la medula osea. El metabolismo del acido desoxirribonucleico se ha estudiado utilizando un precursor especifico, la timidina-{sup 3}H. Comparando los elementos normales y leucemicos que han alcanzado un grado de madurez analogo, se han observado diferencias significativas en el porcentaje de celulas marcadas. Especialmente, en los casos de leucemia aguda, se ha comprobado que la incorporacion de timidina en las celulas leucemicas disminuye muy notablemente. Se estima que estos resultados constituyen una prueba de que la capacidad de proliferacion de estas celulas disminuye en comparacion con la de los mieloblastos normales. Por este mismo procedimiento, se ha estudiado el metabolismo del acido ribonucleico y de las proteinas, utilizando como precursores uridina-{sup 3}H, leucina-{sup 3}H y fenilalanina-{sup 3}H. Actualmente, en biologia celular se admite sin reservas la existencia de una estrecha relacion entre el metabolismo del acido ribonucleico y el de las proteinas. Ademas, se ha

  8. Avaliações clínica, ecográfica e anatomofisiológica do alotransplante parcial de vesícula urinária com células-tronco mesenquimais alogênicas derivadas do tecido adiposo em coelhos

    S. T. L. Pinto Filho

    2015-10-01

    Full Text Available RESUMOOs problemas relacionados ao armazenamento vesical são muitos e relevantes. Eles, além de influírem de forma efetiva na qualidade de vida, podem eventualmente evoluir para falência renal. Existem vários trabalhos, os quais descrevem as propriedades imunomoduladoras e imunossupressoras das células-tronco mesenquimais derivadas do tecido adiposo (ADSCs. Objetiva-se com o presente avaliar clínica, ecográfica e anatomofisiologicamente o alotransplante parcial de bexiga a fresco em coelhos, utilizando como agente imunomodulador ADSCs alogênicas. Para isso foram utilizados 25 coelhos, sendo um deles macho e doador das ADSCs, e os outros 24 eram fêmeas, submetidas a alotransplante parcial de bexiga, sendo tratadas com ciclosporina (GCi ou células-tronco mesenquimais (GCe. Conclui-se que as ADSCs foram suficientes para evitar sinais clínicos e ecográficos de rejeição ao alotransplante de vesícula urinária, mantendo a estrutura anatomofisiológica vesical por até 30 dias em coelhos.

  9. LA RESPONSABILIDAD DE LAS COOPERATIVAS DERIVADA DEL INCUMPLIMIENTO DE LAS OBLIGACIONES CONTABLES. INFLUENCIA DE LA REFORMA PENAL Y LA NUEVA REGULACIÓN CONTABLE / THE CRIMINAL RESPONSABILITY OF THE COOPERATIVES ARISING FROM NOT COMPLYING WITH THE ACCOUNTING OBLIGATIONS. THE REPERCUSSION OF THE REFORM OF THE PENAL CODE AND THE NEW ACCOUNTING REGULATION

    Maria Begoña VILLARROYA LEQUERICAONANDIA

    2012-05-01

    Full Text Available El objetivo perseguido con la realización de este trabajo es conocer la responsabilidad penal derivada del incumplimiento de las obligaciones contables por parte de los órganos sociales de las cooperativas, observando la incidencia de la reforma del Código Penal en la responsabilidad. Para ello, se comienza haciendo una breve descripción de las obligaciones contables, no solo el deber de llevanza de la contabilidad, libros obligatorios,… sino también las obligaciones específicas de las cooperativas recientemente reguladas en la Orden de 21 de diciembre de 2010 sobre los aspectos contables de las sociedades cooperativas (BOE de 29 de diciembre, donde nos encontramos con numerosos cambios en los que parte de las aportaciones de los socios pasarán a calificarse como pasivo. A continuación se analizan los distintos artículos del Código Penal en los que la contabilidad tuviera relevancia, incidiendo en como podría verse afectada la responsabilidad de la empresa con la reciente reforma. / The aim of this work is to know the criminal responsibility for social organs arising from not complying with the accounting obligations and the repercussion of the reform of the Penal Code in the treatment of responsibility. The paper starts with a brief description of the accounting obligations, not only formal but also material obligations, and the specific rules for the valuation of cooperatives that have recently been regulated in the Order of December 21, 2010 (BOE December, 29 of the countable aspects of cooperative companies will be analyzed in this paper. In it we will find numerous changes in whicht parts of the contributions of the partners will be classified as debts.. Finally, this work analyzes various articles of the Criminal Code in which the accounting is most important, highlighting the possibility of responsibility of the companies after the new reform.

  10. Effects of Monoenergetic Neutron Radiation on Human Cells in Tissue Culture; Effets des Neutrons Monoenergetiques sur des Cellules de Tissus Humains en Culture; Dejstvie oblucheniya monoehnergeticheskimi nejtronami na kletki kul'tury tkanej cheloveka; Efectos de la Radiacion Neutronica Monoenergetica sobre las Celulas Humanas en Cultivos de Tejidos

    Broerse, J. J.; Barendsen, G. W. [Radiobiological Institute of the Organization for Health Research TNO, Rijswijk (Z.H.) (Netherlands)

    1964-03-15

    avait lieu dans des bottes de culture a fond mince en Melinex et dans de petits tubes flexibles en nylon et en caoutchouc au silicium. Les auteurs ont determine les flux de neutrons en mesurant l'activation de pastilles de soufre placees, selon les cas, entre les boftes ou entre les tubes. Ils examinent les divers problemes que pose le calcul de la dose d' apres le flux de neutrons. Comme il n'y a pas equilibre du rayonnement autour des cellules, ils analysent les inexactitudes qui en resultent dans les determinations de la dose. Le memoire donne les courbes dose-survie pour les neutrons des deux types. Pour les neutrons de 3 MeV, on a trouve une EBR allant de 6, 5 dans le cas de faibles doses a 3,1 dans le cas de doses elevees; pour les neutrons de 15 MeV, l 'EBR variait de 1,9 a 1,6. En comparant ces valeurs de l'EBR avec le rapport EBR-TLE obtenu au cours d'experiences precedentes avec des deuterons et des particules alpha, on peut calculer le TLE effectif pour les neutrons utilises. Pour resoudre certains problemes relatifs a la mort des animaux d'experience apres exposition aux rayons X ou aux neutrons, les auteurs ont mis au point une technique permettant d'utiliser les cellules contenues dans de petits tubes pour mesurer la dose effective (c'est-a-dire la dose corrigee en fonction de l'EBR) en des points interessants dans des fantomes ou des animaux. (author) [Spanish] Los autores presentan relaciones entre dosis y efecto comprobadas en el estudio de la inhibicion de la formacion de clonos en cultivos de tejido renal humano despues de la irradiacion con neutrones monoenergeticos de unos 3 MeV y unos 15 MeV, respectivamente. Para los neutrones de 3 MeV, la intensidad de dosis fue de 0,2 rad/min, mientras que para los neutrones de 15 MeV, se alcanzaron intensidades de dosis de 2,7 rad/min y 12 rad/min. Las celulas se irradiaron en capsulas de cultivo con fondo delgado de Melinex y en tubos finos flexibles de nylon y de caucho de silicona. Los flujos neutronicos se

  11. The Combined Use of Autoradiographic and Electron Microscopic Techniques for Studies on Ultra-Thin Sections of Tritium-Labelled Cells of the Intestinal Epithelium; Emploi Combine de l'Autoradiographie et du Microscope Electronique pour L'Etude de Coupes Ultra-Fines de Cellules Tritiees de l'Epithelium Intestinal; 0421 043e 0432 043c 0435 0414 ; Empleo Combinado de Tecnicas de Autorradiografia y de MicroscopiA Electronica para Estudiar Cortes Ultrafinos de Celulas Tritiadas del Epitelio Intestinal

    Hampton, J. C. [Division of Experimental Biology, Baylor University College of Medicine, TX (United States); Quastler, H. [Brookhaven National Laboratory, Upton, Long Island, NY (United States)

    1962-02-15

    dans la cellule. Les travaux presentes dans ce memoire demontrent qu'il est possible d'etudier au microscope electronique des coupes ultrafines de cellules marquees, de recuperer l'echantillon apres avoir pris des micrographies electroniques convenables, de l'enduire d'une emulsion suffisamment epaisse pour obtenir une autoradiographie, mais tout de meme assez mince pour permettre un nouvel examen au microscope electronique et obtenir des images micrographiques des autoradiographies deja faites. L'emulsion autoradiographique a ete appliquee comme suit: formation d'une mince pellicule sur une petite boucle de fil metallique plongee dans l'emulsion liquide, puis transfert de la pellicule par passage de la boucle sur l'echantillon monte, fixe a l'extremite d'une chevillette en plastique. On peut effectuer un controle satisfaisant en prenant, lorsqu'on fait les coupes, une coupe d'un demimicron apres chaque coupe ultrafine en la montant sur une lamelle de verre et en appliquant les techniques autoradiographiques classiques. En raison de la fragilite des coupes ultrafines, le nombre d'autoradiographies reussies est tres faible. Malgre cet inconvenient, on peut esperer qu'avec une plus grande experience et un perfectionnement des techniques, cette methode aidera a mieux comprendre les processus des cellules vitales. (author) [Spanish] Merced al elevado grado de resolucion que puede alcanzarse actualmente por observacion de cortes de celulas en el microscopio electronico, resulta posible estudiar algunos de los procesos intracelulares que conducen a la sintesis de las proteinas. La especificidad de la incorporacion de timidina tritiada en la molecula de acido desoxirribonucleico permite seguir detenidamente el desarrollo del proceso en funcion del tiempo y su localizacion dentro de la celula. Los trabajos descritos en la presente memoria demuestran que es posible estudiar por microscopia electronica cortes ultrafinos de celulas tritiadas, retirar la muestra una vez que se han

  12. Germinação e desenvolvimento inicial de plântulas de soja convencional e sua derivada transgênica RR em condições de estresse salino Germination and initial development of soybean seedlings and their transgenic derivatives in salt stress condition

    Tereza Cristina de Carvalho

    2012-08-01

    Full Text Available O Brasil destaca-se como um dos maiores produtores mundiais de soja transgênica, sendo sua produção estendida principalmente a regiões com solos salinos, onde há acúmulo de sais que interferem na germinação da semente e no desenvolvimento das plântulas. O objetivo da pesquisa foi avaliar o efeito do estresse salino sobre a germinação e o desenvolvimento inicial de plântulas de soja convencional e sua derivada transgênica Roundup Ready (RR, submetidas a diferentes condições de salinidade. Para tanto, utilizaram-se dois lotes de sementes de soja (CD 206 e CD 206 RR, sendo que os tratamentos constaram dos seguintes níveis de NaCl: zero; 5; 15; 30; 60 e 120mmol L-1. A avaliação da qualidade fisiológica das sementes foi obtida pelos testes de germinação, comprimento de raiz e plântulas, massa seca de plântulas e volume radicular. O estresse salino reduz a germinação das sementes de ambos os genótipos, sendo que o desenvolvimento de plântulas do genótipo transgênico RR é menos sensível em condições de maior salinidade (60 a 120mmol L-1 de NaCl.Brazil stands out as the largest worldwide producer of transgenic soybeans and has extended its production mainly to regions with saline soils, where there is accumulation of salts that interferes in seed germination and seedling development. The object of this research was to evaluate the effect of saline stress on the germination and initial development of soybean conventional seedling and its transgenic derivatives Roundup Ready (RR submitted to different salinity conditions. For that purpose two lots of soybean seeds were used (CD 206 and CD 206 RR, the treatments consisted of the following levels of NaCl: 0, 5, 15, 30, 60 and 120mmol L-1. The evaluation of physiological seed quality was obtained by germination test, root and seedling length, seedling dry mass and volume of roots. The salt stress reduced germination of seeds of both genotypes, and the development of seedling

  13. Estado actual de las terapias con células madre derivadas de tejido adiposo en el ámbito de la Cirugía Plástica The state of the adipose-derived stem cell therapies in Plastic Surgery

    J.M. Lasso

    2010-09-01

    Full Text Available Durante la última década, la terapia celular ha emergido como una estrategia útil en el tratamiento de diversas enfermedades como la isquemia miocárdica y las fístulas en la enfermedad de Crohn; pero últimamente, hay también ya líneas de investigación centradas en su uso en reconstrucción mamaria, cuyos resultados van siendo publicados paulatinamente. Existen varios tipos de células madre adultas que han sido investigadas en estudios preclínicos y clínicos diseñados para este propósito: células de medula ósea, células del sistema circulatorio y mioblastos y, recientemente se está trabajando en una población de células madre en el tejido adiposo, que presentan una fácil extracción y manipulación. Estas células son capaces de diferenciarse en múltiples líneas celulares, como los adipocitos y las células endoteliales entre otras. En el presente artículo, trataremos de hacer una revisión de los principios básicos de las células madre derivadas del tejido adiposo (tipos, características, procesos de obtención y multiplicación, los primeros estudios experimentales y los ensayos clínicos que están siendo realizados en la actualidad.Over the past decade, cell therapy has emerged as a new approach to reverse several diseases as myocardial ischemia and fistula in Crohn disease; but lately new efforts are centered in breast reconstruction. Several types of adult stem cell have been studied in both preclinical and clinical condition for this purpose: bone marrow cells, circulating cells, and myoblasts. Recently the existence of a population of stem cells located in the adipose tissue has been observed. These cells are able to differentiate into multiple cell lineage including adipocytes and endothelial cells. In this review we discuss the basic principle of adipose-derived stem cell (types, characteristic, harvesting and expansion, the initial experimental studies and the currently ongoing clinical trials.

  14. Stability of RNA and DNA in Bone Marrow Cells, Demonstrated with Tritiated Cytidine and Thymidine; Emploi de la Cytidine et de la Thymidine Tritiees pour Demontrer la Stabilite de l'ARN et l'ADN dans les Cellules de la Moelle Osseuse; 0421 0442 0430 0414 ; Estudio de la Estabilidad de los Acidos Ribonucleico y Desoxirribonucleico de las Celulas de la Medula Osea, Utilizando Citidina y Timidina Tritiadas

    Bond, V. P.; Feinendegen, L. E.; Cronkite, E. P. [Medical Research Centre, Brookhaven National Laboratory, Upton, Long Island, NY (United States)

    1962-02-15

    maniere que l'ADN. L'ARN et l'ADN de formation recente ne se diluent dans les cellules qu'a la faveur de la division cellulaire. (author) [Spanish] Los autores han estudiado el metabolismo de los acidos desoxirribonucleico y ribonucleico utilizando timidina tritiada (timidina-{sup 3}H), un precursor especifico del acido desoxirribonucleico, y citidina tritiada (citidina-{sup 3}H), un precursor comun de los acidos ribonucleico y desoxirribonucleico. Empleando citidina-{sup 3}H se determino autorradiograficamente la incorporacion diferencial por celula en los acidos ribonucleico y desoxirribonucleico, asi como en el espacio soluble. La misma determinacion se efectuo empleando metodos autorradiograficos y quimicos en el caso de poblaciones celulares, mediante extraccion diferencial aplicando un tratamiento apropiado con acido perclorico. Los estudios preliminares sobre renovacion realizados en celulas de HeLa con citidina-{sup 3}H pusieron de manifiesto la funcion precursora del acido ribonucleico nuclear respecto del acido ribonucleico citoplasmatico. La conservacion y distribucion del indicador en la fraccion acido ribonucleico es compatible con una mayor estabilidad de las macromoleculas de dicho acido. Asimismo, la incorporacion continua del indicador en la fraccion acido desoxirribonucleico es compatible con la presencia de un precursor de dicho acido en las ultimas fases de la sintesis. Fenomenos analogos se observaron en las celulas no maduras de la medula osea de la tata, estudiadas durante los dias consecutivos a la administracion de citidina-{sup 3}H por via intravenosa. La actividad del tritio en la fraccion soluble en acido y en las fracciones ARN y ADN se evaluo por metodos quimicos y autorradiograficos. Se comprobo que las tres curvas son paralelas desde el dia que sigue al de inyeccion y paralelas asimismo a las curvas de actividad del tritio en el acido desoxirribonucleico, cuando este se marca con timidina- {sup 3}H. La velocidad de disminucion de la

  15. Stem Cells and Cancer; Celulas madre y cancer

    Segrelles, C.; Paraminio, J. M.; Lorz, C.

    2014-04-01

    Stem cell research has thrived over the last years due to their therapeutic and regenerative potential. Scientific breakthroughs in the field are immediately translated from the scientific journals to the mass media, which is not surprising as the characterisation of the molecular mechanisms that regulate the biology of stem cells is crucial for the treatment of degenerative and cardiovascular diseases, as well as cancer. In the Molecular Oncology Unit at Ciemat we work to unravel the role of cancer stem cells in tumour development, and to find new antitumor therapies. (Author)

  16. Los Errores de Legislar en Paralelo: La Problemática Aplicación de las Reglas sobre Filiación (Determinación, Acciones de Reclamación e Impugnación en la Filiación Derivada del Uso de Técnicas de Reproducción Humana Asistida (Mistakes of Legislating...

    Pilar Benavente Moreda

    2017-03-01

    Full Text Available The incorporation of ‘will’ as a way to define the filiation derived from the use of assisted reproduction techniques (without establishing a new determining method [against the biological and adoptive filiations], plus the recognition of equal marriage and the consequent access to double maternity/paternity, plus the deficient regulation of the text in the assisted reproduction techniques’ law (art. 7, with a general remission to civil laws, have created a legal loophole that is being incoherently covered; all the jurisprudential decisions and disconnected resolution create (or are creating a misadjusted situation that should be confronted with an adequate legislative reform. Are the determination, reclamation and impugnation rules (which are expected in the CC for the filiation by nature really applicable (in a context? out of the special rules expected in the assisted reproduction techniques’ law? La incorporación de la voluntad como forma de determinar la filiación derivada del uso de TRHA, sin establecer una nueva modalidad de determinación (frente a la filiación por naturaleza y la adoptiva, el reconocimiento del matrimonio igualitario y el acceso a la doble paternidad/maternidad derivado de tal reconocimiento, junto con la deficiente regulación en el texto de la LTRHA (art. 7 con su remisión genérica a las leyes civiles, han creado un vacío legal que se está cubriendo de forma incoherente, al albur de decisiones jurisprudenciales y resoluciones desconexas que crean una situación de desajuste que debería afrontarse con una adecuada reforma legislativa. Fuera de las reglas especiales previstas en la LTRHA, ¿resultan aplicables realmente las reglas relativas a la determinación, reclamación e impugnación previstas en el CC para la filiación por naturaleza? Se trata de dar respuesta aquí a las soluciones a las que se llega con los diversos textos legales existentes.DOWNLOAD THIS PAPER FROM SSRN: http

  17. Análise clínica, radiológica, macroscópica e histológica do úmero de codornas domésticas (Coturnix japonica, submetido ao implante da poliuretana derivada do polímero de mamona (Ricinnus communis Clinical, radiological, macroscopical and histological analysis of domestic quail (Coturnix japonica humerus submitted to implant of polyurethane from castor oil polymer (Ricinnus communis

    Juliano Bolson

    2005-10-01

    Full Text Available Na cirurgia ortopédica, são freqüentes as situações em que o cirurgião se depara com grandes perdas ósseas, provocadas especialmente por traumatismos de alta energia, tumores ou infecções. A reparação dessas fraturas requer grande conhecimento a respeito de materiais que possam ser utilizados para preencher essas falhas. Esses materiais podem ser derivados biológicos, sintéticos ou metálicos. Dentre eles, destacam-se os enxertos ósseos e os implantes de biomateriais. Com o aumento dos animais exóticos, utilizados como animais de estimação, a casuística clínica e cirúrgica dessa especialidade vem crescendo, tanto em clínicas quanto em hospitais veterinários. Particularmente, as aves constituem a maioria desses animais, e entre seus problemas cirúrgicos as fraturas são os de maior destaque. O objetivo deste trabalho foi estudar o efeito clínico, radiológico, macroscópico e histológico da poliuretana derivada do polímero de mamona (Ricinnus communis implantada no úmero de codornas domésticas (Coturnix japonica. Para isso, foram utilizadas 20 codornas, machos e fêmeas, separadas aleatoriamente em quatro grupos de cinco animais, os quais receberam o implante no úmero esquerdo, com exame clínico diário durante o período pós-operatório, avaliações radiológica imediata e quinzenal e macroscópica e histológica aos 15, 30, 60 e 90 dias. Clinicamente não foram observadas alterações locais, regionais nem sistêmicas. Ao exame radiológico, notou-se aumento de densidade local, sem sinais de alteração óssea, dos tecidos circunjacentes, e de sacos aéreos. A análise macroscópica revelou que a poliuretana de mamona não foi absorvida em nenhum dos quatro grupos permanecendo implantada no seio do osso pneumático, porém, notou-se alteração em sua resistência. O exame histopatológico mostra inicialmente mínima reação inflamatória, discreta fibrose ao redor do implante e osteointegração pela presen

  18. Las células madre y sus aplicaciones actuales

    Reguero Mera, Marta

    2017-01-01

    Introducción: Se conocen diferentes tipos de células, pero todas ellas tienen una característica en común, que provienen de las células madre. Las células madre, también denominadas células troncales o progenitoras, poseen varias características que las diferencian del resto de células. Existen varias clasificaciones para estas células: dependiendo de su potencial, capacidad de diferenciación o por su origen. El uso de dichas células, o derivadas de éstas, para reparar o renovar tejidos o cél...

  19. Radioisotopes and radiation. Spin-off technologies; Radioisotopos y radiaciones. Tecnologias derivadas

    Bujan, Alfonso [Comision Nacional de Energia Atomica, Ezeiza (Argentina). Centro Atomico Ezeiza

    2001-07-01

    A description is given of the isotope and radiation applications in Argentina. The applications of nuclear techniques in agriculture and animal sciences are reviewed as well as the applications in sedimentology and soil sciences. The use of the sterile insect technique for pest control in some regions of Argentina is described. A review is made of the applications of irradiation for sterilization and food preservation in the country as well as the use of irradiation for industrial processes.

  20. Technologic spin-off from CNEA's activities; Tecnologias derivadas de las actividades de la CNEA

    Belinco, Cesar G [Comision Nacional de Energia Atomica, General San Martin (Argentina). Centro Atomico Constituyentes

    2001-07-01

    An analysis is made of the spin-off of technology from the nuclear activities in Argentina. Several examples are mentioned in fields such as material sciences, non-destructive testing, forensic research, space activities, instrumentation as well as in environmental studies.

  1. PROSPECÇÃO TECNOLÓGICA: MOLÉCULAS BIOATIVAS DERIVADAS DE PRODUTOS NATURAIS

    Thalisson Amorim de Souza

    2014-07-01

    Full Text Available Moléculas bioativas são provenientes da purificação de extratos naturais através de técnicas de separação, como cromatografia. O estudo fitoquimico dessas moléculas vem se desenvolvendo devido ao potencial farmacológico, representando dessa maneira uma alternativa as terapias convencionais. Essa prospecção tecnológica tem por objetivo revelar o panorama mundial das moléculas biotivas e suas aplicações. Para tal, foi realizada um levantamento em base de dados de patentes, INPI (Instituto Nacional de Propriedade Industrial e WIPO (Organização Mundial de Propriedade Intelectual. Assim, evidenciou-se que a China seguida dos EUA lideram o ranking de patentes depositadas.Também foi perceptivel a existência de um número grande de patentes em âmbito internacional em relação as registradas nacionalmente.

  2. El concepto de derivada en estudiantes de educación media

    Victor Manuel Dominguez-Contreras

    2016-01-01

    Full Text Available The article shows the characterization of geometric reasoning levels applied to the concept of derivative in a sample of 40 students of secondary education, in which the different levels are described, determined and compared, the research showed that it is possible to apply the levels of Geometric reasoning. Conclusion: Van Hiele model allows to evaluate the level of geometric reasoning in which the students of secondary education are located regarding the concept of derivative.

  3. Responsabilidad civil derivada de la inclusión indebida en un registro de morosos

    Lagunas Reyes, Lucia

    2014-01-01

    El presente trabajo se aborda con motivo de la reciente Sentencia del Tribunal Supremo (Sala de lo Civil) núm. 176/2013, de 6 marzo. Avanzando en la línea marcada por sentencias precedentes, el Tribunal Supremo declara que “la inclusión de datos personales en un registro de morosos por una deuda dudosa vulnera el derecho al honor”. La citada sentencia del Tribunal Supremo asume como propia la doctrina del Tribunal Supremo ya consolidada, según la cual la inclusión incorrecta de datos en u...

  4. LA ESTRUCTURA ESCOLAR INHIBIDORA DEL APRENDIZAJE ORGANIZACIONAL: EXPERIENCIA DERIVADA DE CASO

    David Simonetta

    2010-01-01

    Full Text Available El presente artículo describe resultados y conclusiones de una investigación realizada en un centro escolar de nivel medio llamado Instituto Brigadier General Martín Rodríguez, de financiamiento público y gestión privada, de la ciudad de Tandil, provincia de Buenos Aires, República Argentina. En este artículo se ha abordado la problemática de la estructura del centro escolar y su impacto en la gestión del conocimiento y la generación de aprendizaje organizacional en la escuela. Se investigó distinta bibliografía referida a la estructura organizacional, la gestión del conocimiento, las teorías denominadas principios, disciplinas, o procesos de aprendizaje organizacional, y organización y gestión de centros escolares. Se ha planteado a partir de allí el modelo de observación que caracteriza la dinámica y evolución del aprendizaje organizacional y sus efectos. Directivos, Docentes, Personal de apoyo, Alumnos aportaron sus opiniones para este trabajo. Bajo este modelo de abordaje, se evidencian en el caso planteado características estructurales predominantemente inhibidoras de los procesos de aprendizaje organizacional. Respecto de los conocimientos tratados e intercambiados entre personas del centro escolar, existe un exceso de cuestiones analíticas, en detrimento de creaciones originales o nuevas prácticas a partir de dichos procesos organizacionales. Es decir, no solo la estructura impide el aprendizaje organizacional, sino que además la característica del conocimiento intercambiado lo vuelve no benéfico organizacionalmente hablando.

  5. Biomass gasification and fuel cells: system with PEM fuel cell; Gaseificacao de biomassa e celula a combustivel: sistema com celula tipo PEMFC

    Sordi, Alexandre; Lobkov, Dmitri D.; Lopes, Daniel Gabriel; Rodrigues, Jean Robert Pereira [Universidade Estadual de Campinas (UNICAMP), Campinas, SP (Brazil). Fac. de Engenharia Mecanica], e-mail: asordi@fem.unicamp.br, e-mail: lobkov@fem.unicamp.br, e-mail: danielg@fem.unicamp.br, e-mail: jrobert@fem.unicamp.br; Silva, Ennio Peres da [Universidade Estadual de Campinas (UNICAMP), Campinas, SP (Brazil). Inst. de Fisica Gleb Wataghin], e-mail: Lh2ennio@ifi.unicamp.br

    2006-07-01

    The objective of this paper is to present the operation flow diagram of an electricity generation system based on the biomass integrated gasification fuel cell of the type PEMFC (Proton Exchange Membrane Fuel Cell). The integration between the gasification and a fuel cell of this type consists of the gas methane (CH4) reforming contained in the synthesis gas, the conversion of the carbon monoxide (CO), and the cleaning of the gaseous flow through a PSA (Pressure Swing Adsorption) system. A preliminary analysis was carried out to estimate the efficiency of the system with and without methane gas reforming. The performance was also analyzed for different gasification gas compositions, for larger molar fractions of hydrogen and methane. The system electrical efficiency was 29% respective to the lower heating value of the gasification gas. The larger the molar fraction of hydrogen at the shift reactor exit, the better the PSA exergetic performance. Comparative analysis with small gas turbines exhibited the superiority of the PEMFC system. (author)

  6. Repercusiones sobre la presión arterial y las células progenitoras CD34+ tras diferentes tipos de entrenamiento

    Niño Mendez, Oscar Adolfo

    2015-01-01

    [spa] En la actualidad existe una gran evidencia científica sobre los múltiples beneficios que ofrecen la actividad física y el ejercicio físico en la promoción y mantenimiento de la salud. Los diferentes estudios han mostrado un abanico de resultados favorables en todas las poblaciones estudiadas. El correcto funcionamiento del endotelio vascular es de vital importancia en la salud cardiovascular y la incorporación de programas de ejercicio físico pueden representar un medio eficaz en la ate...

  7. Coleta de células progenitoras periféricas por aférese automatizada em equino: relato de procedimento

    J.O. Bernardo

    Full Text Available ABSTRACT The biotechnology used in tendon, bone and joint recoveries in Equine Medicine has improved in recent years. The most used are platelet rich plasma and stem cells from adipose tissue and bone marrow. However, recent studies have shown that stem cells can be found in the bloodstream, also named peripheral blood progenitor cells (CPP. This note aims at reporting the feasibility of automated collection of CPP in horses. The procedure was conducted in an equine, female, Quarter Horses, 2 years old, 385kg. The automated collection of CPP was conducted using apheresis equipment Fresenius- Kabi coupled to C4Y kit. The procedure lasted two hours and 30 minutes without complications, processing 5054mL of whole blood and obtaining 351mL of CPP. Upon completion of the collection, the content of CPP was separated into 10 ml aliquots and immediately stored at -18°C. The automated technique proved to be feasible for horses, but needs improvement in order to achieve greater efficiency and reduce procedure time.

  8. Membranes for hydrogen and fuel cell technology; Membranas para celula combustivel e separacao de hidrogenio

    Nunes, Suzana Pereira [GKSS-Forschungszentrum, Geesthacht (Germany)]. E-mail: nunes@gkss.de

    2005-07-01

    Membranes for fuel cell were prepared using as polymer matrix sulfonated polyether ketones. New sulfonated copolymers (poly oxazoles, poly imides and poly ketones) were synthesized. Nano composites using zirconium oxide and phosphates, as well as modified silicates were obtained aiming the application on direct methanol fuel cell (DMFC). The performances of membranes containing fillers with different aspects (spherical, layers, tubular, networks) and surface modification (hydroxy, imidazole, acid oligomers) were compared. The effect of surface modification was much more pronounced than that of the aspect. A good balance of proton conductivity and methanol permeability was obtained with silicates modified with imidazole groups. Good performance in DMFC were obtained with membranes containing zirconium phosphate. Acid oligomers also led to particularly high conductivity values above 100 deg C. Polyimide membranes with H{sub 2}/CH{sub 4} larger than 100 were obtained. (author )

  9. Electrochemical studies for an acid fuel cell; Estudos eletroquimicos de uma celula a combustivel acida

    Gonzalez, E.R.; Avaca, L.A.; Ticianelli, E.A.; Ferreira, A.C.; Oliveira, J.C.T. de [Sao Paulo Univ., Sao Carlos, SP (Brazil). Inst. de Fisica e Quimica

    1984-12-31

    This work describes the main steps for the development of the components of an one-kilowatt phosphoric acid H{sub 2}/O{sub 2} fuel cell stack. The electrochemical characteristics of fundamental components-electrodes and electrolyte-matrix have been evaluated in unitary fuel cell prototype by stationary polarization curves and continuous operation curves. The results confirmed the better efficiency of the hydrogen electrode and anticipated a very fair performance for the one-kilowatt stack. (author). 4 figs., 5 refs

  10. En búsqueda de marcadores de celulas madre mesenquimales de la pulpa dental

    Merino, Graciela; Dewey, Ricardo; Mayocchi, Karina; Butler, Teresa Adela; Dorati, Pablo; Basal, Roxana Lía; Paggi, Ricardo; Cantarini, Martín; Pinola, Lidia; Micinquevich, Susana

    2016-01-01

    Al plantearse aislar y cultivar células madre de la pulpa dental, es Importante conocer sus características morfológicas, inmunohistoquímica, ultraestructurales y moleculares. Respecto a la inmunohistoquímica se conocen moléculas marcadoras ubicadas en la superficie celular. Ellas tienen la propiedad de reconocer determinados anticuerpos. Las siglas utilizadas para su Identificación se reconocen como CD (Cluster of Differentiation). El objetivo del presente trabajo fue diseñar una tabla, en b...

  11. Clinical applications of cells labelling; Aplicaciones clinicas del marcado de celulas

    Gonzalez, B M [Instituto Nacional de Pediatria (Mexico)

    1994-12-31

    Blood cells labelled with radionuclides are reviewed and main applications are described. Red blood cell labelling by both random and specific principle. A table with most important clinical uses, 99mTc labelling of RBC are described pre tinning and in vivo reduction of Tc, in vitro labelling and administration of labelled RBC and in vivo modified technique. Labelled leucocytes with several 99mTc-complex radiopharmaceuticals by in vitro technique and specific monoclonal s for white cells(neutrofiles). Labelled platelets for clinical use and research by in vitro technique and in vivo labelling.

  12. Automation of cells of radiopharmaceuticals production; Automacao de celulas de producao de radiofarmacos

    Negrini, Aguinaldo Donizete

    2010-07-01

    The {sup 67}Ga is an important radiopharmaceutical used to identify inflammatory processes in chronic illnesses, diagnosis by image of tumors in soft tissues and the possibility to evaluate the result for therapeutic intervention. In the present work a module of {sup 67}Ga processing was developed with the objective to reduce the interventions in the hot cell, in order to avoid oxidation caused by metallic materials, and consuming in hoses of the peristaltic pumps, that release residues that blocked the valves used in the process. With materials such as: acrylic, PVC, PEEK e teflon and they are used vacuum as method (way) of fluid transferences instead of peristaltic pump in the majority of the procedures, with this improvements the system can make shorter the lengths of transference hoses, increasing the yield in the process with less interventions for maintenance and time exposure of the workers, guaranteeing the quality and reducing the time of the processing. using a mobile system for displacement of the processing module making in the cleanness and maintenance of the cell that works with radioactive material. Reducing the time of exposure dose of the workers in compliance with RDC-17 of ANVISA, which ruling the Good Manufacturing Practice Procedures. (author)

  13. Electrochemical studies for an acid fuel cell; Estudos eletroquimicos de uma celula a combustivel acida

    Gonzalez, E R; Avaca, L A; Ticianelli, E A; Ferreira, A C; Oliveira, J C.T. de [Sao Paulo Univ., Sao Carlos, SP (Brazil). Inst. de Fisica e Quimica

    1985-12-31

    This work describes the main steps for the development of the components of an one-kilowatt phosphoric acid H{sub 2}/O{sub 2} fuel cell stack. The electrochemical characteristics of fundamental components-electrodes and electrolyte-matrix have been evaluated in unitary fuel cell prototype by stationary polarization curves and continuous operation curves. The results confirmed the better efficiency of the hydrogen electrode and anticipated a very fair performance for the one-kilowatt stack. (author). 4 figs., 5 refs

  14. Efficiency of SOFC type fuel cells; Eficiencia de celulas combustiveis do tipo SOFC

    Amaral, Alexandre Alves do; Matos, Francisco F.; Boaventura, Jaime S.; Benedicto, Joao Paulo S.; Alencar, Marcelo [Universidade Federal da Bahia (UFBA), Salvador, BA (Brazil). Inst. de Quimica. Dept. de Fisico-Quimica

    2006-07-01

    production of electric energy, mainly due to the fact that it is virtually no pollutant. Typically, the SOFC is constituted of at least seven distinct phases: fuel, anode, electrolyte substrate (separating the two electrodes), cathode, air, and electrical inter connectors (completing the electrical circuit). Thermodynamics clearly shows that electrochemical systems only can be reversible when homogeneous, what it is not case of the Sofc. Therefore, the application of equilibrium thermodynamics to these systems is incorrect. This work proposes that the Sofc can be better depicted from reactions between adsorbed species. The efficiency then is calculated as the ratio between the free energy of these reactions to the combustion heat. Thermodynamic parameter estimative is developed for the global and adsorbed species reactions. (author)

  15. Development of solid oxide fuel cells; Desenvolvimento de celulas a combustivel do tipo oxido solido (SOFC)

    Boaventura, Jaime S.; Alencar, Marcelo Goncalves F. de; Amaral, Alexandre Alves do; Benedicto, Joao Paulo Santos; Silva, Marcos A. [Universidade Federal da Bahia (UFBA), Salvador, BA (Brazil). Inst. de Quimica. Dept. de Fisico-Quimica

    2006-07-01

    Fuel cells allow the energy production without the thermodynamic restriction of the conversion of heat into work. Among their various types, the solid oxide fuel cells (SOFC), operating at high temperatures, allow the methane conversion into electricity directly on the anode. The main element of the SOFC is the structure A/E/C: anode/electrolyte/cathode, all sintered at high temperature as resistant ceramic materials. Dense electrolyte (YSZ: zirconia stabilized for Yttria) separates the anode (Ni+Co/YSZ: cobalt promoted nickel, supported on YSZ) and cathode (LSM: strontium-doped lanthanum manganite), both with porosity obtained by graphite addition. To obtain suitable A/E/C pellets, the layer sintering with appropriate mechanical and textural characteristics is essential, requiring excellent electric junctions between them. The cell performance has been evaluated between 850 and 950 degree C, using hydrogen or methane fuel; the tension and current for different resistance values in the electrical circuit have been measured. The cobalt addition to the cell anode significantly increased its activity for the reform reaction. The beneficial effect was probably due to the easier nickel reduction in cobalt presence. This work had the objectives of developing and evaluating electro-catalysts, as well as the solid oxide fuel cells using these catalysts as anode. Five SOFC models (SOFC 1 to SOFC 5) are described; all of them were developed aiming at improving the preparation of the anode/electrolyte/cathode structure (A/E/C). (author)

  16. Tumor cells diagnostic through fractal dimensions; Diagnostico de celulas tumorais atraves de dimensoes fractais

    Timbo, Christiano dos Santos

    2004-07-01

    This method relies on the application of an algorithm for the quantitative and statistic differentiation of a sample of cells stricken by a certain kind of pathology and a sample of healthy cells. This differentiation is made by applying the principles of fractal dimension to digital images of the cells. The algorithm was developed using the the concepts of Object- Oriented Programming, resulting in a simple code, divided in 5 distinct procedures, and a user-friendly interface. To obtain the fractal dimension of the images of the cells, the program processes the image, extracting its border, and uses it to characterize the complexity of the form of the cell in a quantitative way. In order to validate the code, it was used a digitalized image found in an article by W. Bauer, developer of an analog method. The result showed a difference of 6% between the value obtained by Bauer and the value obtained the algorithm developed in this work. (author)

  17. Reporte de caso Adenocarcinoma de celulas basales de glandula parotida: estudio clinico/patologico e inmunohistoquimico

    Pedro Emilio García

    Full Text Available Resumen: El adenocarcinoma de células basales es una neoplasia epitelial con las características citológicas del adenoma de células basales pero con un patrón morfológico de crecimiento infiltrante indicativo de malignidad. Debido a su baja incidencia es a menudo difícil de diagnosticar. El objetivo del presente estudio fue identificar características morfológicas e inmunohistoquímicas que contribuyen a su diagnóstico. Se resecó un tumor de parótida en una paciente de 52 años; se realizó biopsia postoperatoria e inmunomarcación con Ki-67, CK19, p63 y alfa actina de músculo liso. Se diagnosticó adenocarcinoma de células basales mixto sólido y tubular con invasión perineural y de la cápsula tumoral, grasa periglandular y nodos linfoides. La inmunomarcación con Ki-67, CK19, p63 y alfa actina de músculo liso resultó positiva. Posteriormente se diagnosticó una metástasis en seno maxilar. Las características morfológicas, la inmunomarcación Ki-67 positiva y la metástasis le dan el carácter maligno a este tumor, lo que lo diferencia del adenoma de células basales.

  18. Terapêutica do carcinoma pulmonar não de pequenas celulas

    Renato Sotto-Mayor

    2002-05-01

    Full Text Available RESUMO: No presente artigo de revisão o autor aborda a terapêutica do carcinoma pulmonar nao de pcquenas células em função do estádio de apresentação da doença, dando especial relevo à sua abordagem multidisciplinar, no sentido de ultrapassarmos o mau prognóstico que o seu diagnóstico ainda acarreta.Discute o Iugar das diferentes modalidades terapêuticas, a terapeutica da recidiva e da progressão tumorais, a do cancro do pulmao no doente idoso, o papel dos novos fármacos e as potencialidades dos novos alvos terapêuticos a nivel da biologia celular e molecular.REV PORT PNEUMOL 2002; Vlll (3: 237-259 ABSTRACT: In the present paper, the author reviews the non-small-cell lung cancer treatment by stages of disease.He states about the therapeutic strategies involving surgery, radiation therapy and chemotherapy, the important role of the multimodality approach of the patients, the relapsing and refractory tumor, the elderly patient, the new drugs, and the potential role of new gene and cell­ -based therapies.REV PORT PNEUMOL 2002; VIII (3: 237-259 Palavras-chave: carcinoma do pulmão, terapêutica, Key-words: Lung cancer, therapeutic

  19. Feasibility of biogas utilization in fuel cells; Viabilidade do uso de biogas em celulas a combustivel

    Sprenger, Humberto Elias [Programa de Pos-graduacao em Desenvolvimento de Tecnologia (PRODETEC/LACTEC/IEP), Cutitiba, PR (Brazil); Cantao, Mauricio Pereira [Instituto de Tecnologia para o Desenvolvimento (LACTEC), Curitiba, PR (Brazil)], E-mail: mauricio.cantao@utp.br

    2010-10-15

    Waste water treatment stations using upflow anaerobic sludge blanket (UASB) produce biogas, composed of carbon dioxide diluted methane plus minority compounds. This kind of reactor is worthwhile but demands methane burning in order to reduce atmospheric pollution and damage to ozone layer. Meanwhile, biogas can be used for energy generation due to its heating value. In this paper a technical and economic feasibility study about the use of biogas as a hydrogen source for fuel cells feeding is presented. Two methods for assessment of biogas production in UASB reactor were compared for ETE Atuba Sul case. (author)

  20. La responsabilidad bancaria derivada de las operaciones de crédito en el derecho francés

    Mónica Rodríguez González

    2011-07-01

    Full Text Available El recurso al préstamo bancario es de vital importancia para la constitución y buen funcionamiento de las empresas, especialmente de las de pequeña y mediana talla. Esta relación de dependencia entre empresas y bancos es aun mayor cuando la empresa se ve obligada a entrar en un régimen de insolvencia. En Francia existía un régimen de responsabilidad bancaria por daños ocurridos en el ejercicio de la actividad crediticia. Las hipótesis eran: a rechazo del crédito, b ruptura abusiva de la relación crediticia, c concesión de un crédito ruinoso y, d sostenimiento abusivo de la relación crediticia. Pero una ley de 2005 vino a desmontar este régimen de responsabilidad, estableciendo un principio de irresponsabilidad, con solo tres excepciones. La eficacia de la ley, sin embargo, puede cuestionarse.

  1. Isolamento e caracterização de células-tronco mesenquimais derivadas de anexos fetais equinos

    De Vita, Bruna [UNESP

    2011-01-01

    O interesse nas pesquisas com células-tronco obtidas dos anexos fetais de diversas espécies aumentou muito nas últimas décadas em virtude de serem fontes de células-tronco adultas com potencial de diferenciação em diversas linhagens celulares, sem riscos de desenvolvimento de tumores malignos ao serem transplantadas e com a vantagem de possibilitar bancos de armazenamento, no entanto, os estudos para espécie equina ainda são escassos. O objetivo deste trabalho foi isolar, caracterizar e difer...

  2. Some examples of spin-off technologies: San Carlos de Bariloche; Algunos ejemplos de tecnologias derivadas: San Carlos de Bariloche

    Meyer, Gabriel O [Comision Nacional de Energia Atomica, San Carlos de Bariloche (Argentina). Centro Atomico Bariloche

    2001-07-01

    The Bariloche Atomic Center (CAB) and the Balseiro Institute, both in San Carlos de Bariloche, are mainly devoted to scientific research and development, the first one; and to education and training the second one. Besides providing specialists in physics and nuclear engineering for research centers in Argentina and abroad, both establishments are transferring technologies and providing services in different fields such as waste management, metallurgy, forensic sciences, medicine, geology, modeling, archaeology, paleontology, etc.

  3. Desigualdades territoriales en México derivadas del tratado de libre comercio de América del Norte

    Javier Delgadillo Maclas

    2008-04-01

    Full Text Available La instrumentación del Tratado de Libre Comercio de América del Norte (TLCAN a partir del año 1994 consolidó una etapa de libe ral ización económica iniciada en México a partir de 1982. La sistemática operación del TLCAN en los distintos sectores de la economía (incorporados a este acuerdo comercial se vio al mismo tiempo acompañada de efectos territoriales favorables en algunos casos, y de dimensiones críticas para un número importante de regiones y estados que componen la federación mexicana. Después de 14 años de su inicio, en este trabajo se analizan los procesos de reestructuración espacial desde entonces generados, las disparidades regionales asociadas al nuevo escenario internacional, y se da cuenta de las relaciones económicas que contraponen a la etapa actual del modelo neoliberal imperante con aquellas otras formas tradicionales de organización excluidas y que aún mantienen en México buena proporción de espacios socialmente marginadosThe coming into force of the North American Free Trade Agreement (NAFTA from 1994 consolidated a phase of Mexican economic liberalization that had begun in 1982. The systematic operationalization of the NAFTA in different sectors of the economy (incorporated into this commercial agreement was also accompanied by favorable spatial impacts in some cases, and unfavorable impacts for a significant number of regions and states of the Mexican federation. Fourteen years on, this article analyzes the processes of spatial restructuring that have been generated, the regional disparities associated with the new international scenario, and explains the economic relations that run in opposition to the current stage of the dominant neoliberal model, which has excluded other traditional forms of organization and has kept many areas of Mexico in a condition of social marginalization

  4. Program for the radiological protection of the embryos-fetuses due to the medical exposure of him mother; Programa para la proteccion radiologica del embrio-feto debido a la exposicion medica de su progenitora

    Lopez B, G M; Martinez G, A; Cardenas H, J; Gonzalez R, N; Valdes R, M; Zaldivar H, W [CPHR, Calle 20 No. 4113 e/41 y 47, Playa C.P. 11300, La Habana (Cuba)

    2006-07-01

    In the last years the organizations in charge of the regulation in matter of radiological protection, its have adopted measures to minimize the risks derived of the medical exposures, paying special attention to those that involve women in age of procreation, gestating and in period of lactation, because the embryo - fetus and the newborn babies ones are very vulnerable to the risks of the ionizing radiations, which can end up producing them multiple effects of variable severity. In Cuba, a Maternal-children program that includes the genetic advice to the pregnant woman from the medical point of view exists but didn't so the evaluation of the radiological risk; which is only carried out by the Medical Surveillance Service of the Protection and Hygiene of the Radiations Center (CPHR), without that mediates an official link among both parts and whose existence is only known by a reduced group of professionals of the health and of specialists in Radiological Protection. On the other hand is not established a strategy at national level for the differentiated information and systematic in these topics that it contributes to the control of the exposures of the embryo fetus and the breast-fed baby. Keeping in mind the above-mentioned the specialists of the CPHR have elaborated a proposal of national program for the radiological protection of the embryo- fetus due to the medical exposure of its progenitor. In the same one it is settles down the interrelation between work groups and multidisciplinary institutions to achieve the detection, communication and consultant ship of the cases of exposure to the fetus or breast-fed baby that happen in the country and at the same time include the training so much of the professionals of the health like of the public in general. Presently work the program and the elements that conform it among those that are, the on-line system developed for the automation of the medical dosimetric evaluation, the technician-methodological documents on this topic as well as the informative and instructive tools directed to the professionals and the public in general are described. (Author)

  5. 57. El menor número de células progenitoras endoteliales en la sangre periférica de pacientes coronarios no está relacionado con una disfunción in vitro inducida por su plasma

    A. González Rocafort

    2010-01-01

    Conclusiones: Los pacientes coronarios tienen un menor nivel preoperatorio de EPC que los valvulares. La disfunción en cultivo de las EPC de pacientes ateroscleróticos no se observa en EPC cultivadas obtenidas de donantes sanos tras la incubación con plasma de pacientes coronarios, y, por lo tanto, podría ser debida más a factores intrínsecos de estas células en su procedencia de la médula ósea que a factores del medio.

  6. Program for the radiological protection of the embryos-fetuses due to the medical exposure of him mother; Programa para la proteccion radiologica del embrio-feto debido a la exposicion medica de su progenitora

    Lopez B, G.M.; Martinez G, A.; Cardenas H, J.; Gonzalez R, N.; Valdes R, M.; Zaldivar H, W. [CPHR, Calle 20 No. 4113 e/41 y 47, Playa C.P. 11300, La Habana (Cuba)]. e-mail: gladys@cphr.edu.cu

    2006-07-01

    In the last years the organizations in charge of the regulation in matter of radiological protection, its have adopted measures to minimize the risks derived of the medical exposures, paying special attention to those that involve women in age of procreation, gestating and in period of lactation, because the embryo - fetus and the newborn babies ones are very vulnerable to the risks of the ionizing radiations, which can end up producing them multiple effects of variable severity. In Cuba, a Maternal-children program that includes the genetic advice to the pregnant woman from the medical point of view exists but didn't so the evaluation of the radiological risk; which is only carried out by the Medical Surveillance Service of the Protection and Hygiene of the Radiations Center (CPHR), without that mediates an official link among both parts and whose existence is only known by a reduced group of professionals of the health and of specialists in Radiological Protection. On the other hand is not established a strategy at national level for the differentiated information and systematic in these topics that it contributes to the control of the exposures of the embryo fetus and the breast-fed baby. Keeping in mind the above-mentioned the specialists of the CPHR have elaborated a proposal of national program for the radiological protection of the embryo- fetus due to the medical exposure of its progenitor. In the same one it is settles down the interrelation between work groups and multidisciplinary institutions to achieve the detection, communication and consultant ship of the cases of exposure to the fetus or breast-fed baby that happen in the country and at the same time include the training so much of the professionals of the health like of the public in general. Presently work the program and the elements that conform it among those that are, the on-line system developed for the automation of the medical dosimetric evaluation, the technician-methodological documents on this topic as well as the informative and instructive tools directed to the professionals and the public in general are described. (Author)

  7. Poly (ether ether ketone) membranes for fuel cells; Membranas de poli (eter eter cetona) sulfonado para celulas a combustivel

    Marrero, Jacqueline C.; Gomes, Ailton de S.; Filho, Jose C.D., E-mail: jacquecosta@gmail.com [Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ (Brazil); Hui, Wang S. [Universidade de Sao Paulo (USP), Sao Paulo, SP (Brazil); Oliveira, Vivianna S. de [Escola Tecnica Rezende-Rammel, Rio de Janeiro, RJ (Brazil)

    2015-07-01

    Polymeric membranes were developed using a SPEEK polymer matrix (sulphonated poly (ether ether ketone)), containing hygroscopic particles of zirconia (Zr) (incorporated by sol-gel method), for use as electrolyte membranes in fuel cells. SPEEK with different sulfonation degrees were used: 63 and 86%. The thermal analysis (TGA and DSC) was carried out to characterize the membranes and electrochemical impedance spectroscopy (EIS) was carried out to evaluating the proton conductivity of the membranes. Additional analysis were underway in order to characterize these membranes, which include: X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) in order to evaluate the influence of zirconia and sulfonation degree on the properties of the membranes. (author)

  8. Evaluation of sulphonated polycarbonate membranes for fuel cells; Avaliacao de membranas de policarbonato sulfonado para celulas a combustivel

    Machado, Isabela M.M.; Gomes, Ana C.; Pessan, Luiz A. [Universidade Federal de Sao Carlos (UFSCAR), SP (Brazil). Dept. de Engenharia de Materiais], e-mail: isabelamuglia@gmail.com; Paranhos, Caio [Universidade Federal de Sao Carlos (UFSCAR), SP (Brazil). Dept. de Quimica

    2011-07-01

    Fuel cells based on ion conducting polymer membranes offer an alternative for the conventional energetic matrices. Among many advantages of this system, we can mention the reduction on the emission of pollutants, high efficiency and simplicity. This work presents the modification of polycarbonate by sulfonation reaction using acetyl sulfate, in order to increase the conductor ionic character of the membranes used as electrolytes for hydrogen fuel cells. The sulfonated polycarbonate membranes were obtained by casting and then characterized by Fourier transform infrared spectroscopy, water vapor transmission, differential scanning calorimetry, thermogravimetric analysis and viscosimetry. (author)

  9. Photostability Assessment in Amorphous-Silicon Solar Cells; Determinacion de la Fotoestabilidad en Celulas Solares de Silicio Amorfo

    Gandia, J. J.; Carabe, J.; Fabero, F.; Jimenez, R.; Rivero, J. M. [Ciemat, Madrid (Spain)

    2000-07-01

    The present status of amorphous-silicon-solar-cell research and development at CIEMAT requires the possibility to characterise the devices prepared from the point of view of their stability against sunlight exposure. Therefore a set of tools providing such a capacity has been developed. Together with an introduction to photovoltaic applications of amorphous silicon and to the photodegradation problem, the present work describes the process of setting up these tools. An indoor controlled-photodegradation facility has been designed and built, and a procedure has been developed for the measurement of J-V characteristics in well established conditions. This method is suitable for a kinds of solar cells, even for those for which no model is still available. The photodegradation and characterisation of some cells has allowed to validate both the new testing facility and method. (Author) 14 refs.

  10. Development of solid oxide fuel cells (SOFC); Desenvolvimento de celulas a combustivel do tipo oxido solido (SOFC)

    Souza, F.M.B. de; Carvalho, L.F.V. de; Alencar, M.G de; Boaventura, J.S. [Universidade Federal da Bahia (DFQ/UFBA), Salvador, BA (Brazil). Dept de Fisico-Quimica. Grupo de energia e Ciencias dos Materiais], e-mail: bventura@ufba.br

    2008-07-01

    The most promising technology for generating electric power, with reduced environmental impact, is the fuel cell. This technology is virtually non-polluting and the fuel supplies can be renewable. Therefore is necessary to study the technique of preparing the entire anode / electrolyte / cathode to optimize its operation. There are still major challenges to making the SOFC economically viable. The key is the improvement of manufacturing of its components and use of materials that can simultaneously reduce costs and reduce the temperature of operation. Among the properties of the cell, was shown the dependence of the efficiency of the device on the properties of the electrolyte, particularly its thickness. The mixture of YSZ with GDC in the composition of the anode and electrolyte aims to obtain a material with greater ionic conductivity. After sintering the cell was characterized by scanning electron microscopy (SEM). (author)

  11. Fuel cells cathode with multiple catalysis and electrocapillary convection; Catodo de celula a combustivel com catalise multipla e conveccao eletrocapilar

    Bambace, Luis Antonio Waack; Nishimori, Miriam; Ramos, Fernando Manuel [Instituto Nacional de Pesquisas Espaciais (INPE), Sao Jose dos Campos, SP (Brazil)], e-mail: bambace@dem.inpe.br; Bastos Netto, Demetrio [Instituto Nacional de Pesquisas Espaciais (INPE), Cachoeira Paulista, SP (Brazil)

    2004-07-01

    This paper discusses a mathematical model for the chemical reactions and liquid phase flow processes occurring in a fuel cell cathode through non homogeneous catalysis carried by gold and Prussian Blue. The gold is applied inside the porous walls of micro-tubes, which may be obtained through several methods. The wall porosity ranging from 7 to 30% ensures gas exchange between the interior of a micro-tube and its exterior where gas flow takes place. The Prussian Blue consists of a thin porous layer located between the selective membrane and the micro-tube system, with void fraction in the 70 to 80% range. A porous electricity conducting carbide flux collector is placed between the tube system and the bipolar plates. The system return tubes possess a diameter much larger than one of the micro-tubes. The electric potential differences generated by the ionic currents in the system and its asymmetrical shape are used to generate electrocapillary flows, which are related with the surface tension changes with local potential. The hydrogen peroxide concentration and its transport to the Prussian Blue layer, and the oxygen transport inside the reactive tubular system are analyzed in this work. (author)

  12. Electrochemical characterization of proton exchange membrane fuel cells; Caracterizacao eletroquimica de celulas a combustivel de membrana polimerica trocadora de protons

    Furtado, Jose Geraldo de Melo; Serra, Eduardo Torres [Centro de Pesquisas de Energia Eletrica (CEPEL), Rio de Janeiro, RJ (Brazil)]. E-mail: furtado@cepel.br; Codeceira Neto, Alcides [Companhia HidroEletrica do Sao Francisco (CHESF), Recife, PE (Brazil)

    2008-07-01

    This paper describes the electrochemical behavior of a proton exchange membrane fuel cell in function of temperature and time of operation. Different polarization phenomena are considered in the 30 to 70 deg C temperature range, as well as the degradation of electrochemical behavior of the fuel cell analyzed up to 1260 hours of operation. The results show that there is a tendency for the experimental values approaching the theoretical as it increases the temperature of the membrane electrolyte. The electrochemical behavior of the PEMFC studied proved to be less stable at 70 deg C. On the other hand, at 30 deg C the fuel cell performance proved to be considerably lower than at other temperatures. Also, it was found that in certain current ranges occurs greater overlay in potential-current curves, and in some cases reversing between these curves depending on the electric current required for the data obtained at 60 and 70 deg C, indicating, perhaps, that at 70 deg C the characteristics of the electrolyte are slightly inferior to those at 70 deg C, corresponding to an electrolyte degradation. Additionally, for the system studied, we found that the rate of variation of the potential difference in function of the temperature is quite high at the beginning of the operation process and tends to stabilize in a level of around 2,3-2,5 {mu}V per minute for times greater than 330 hours of operation. (author)

  13. Experimental study of proton exchange membrane fuel cell; Estudo experimental de uma celula a combustivel de membrana polimerica

    Acevedo, Luis Evelio Garcia; Oliveira, Amir Antonio Martins [Universidade Federal de Santa Catarina (UFSC), Florianopolis, SC (Brazil). Dept. de Engenharia Mecanica], e-mail: evelio@labcet.ufsc.br, e-mail: amirol@emc.ufsc.br

    2006-07-01

    Here we present a thermodynamic and chemical kinetic analysis of the methane steam reforming for production of 5 kw of electrical power in a PEM fuel cell. The equilibrium analysis is based on the method of element potentials to find the state of minimum Gibbs free energy for the system and provides the equilibrium concentration of the reforming products. The objective of this analysis is to obtain the range of reforming temperature, pressure and steam-methane molar ratio that results in maximum hydrogen production subjected to low carbon monoxide production and negligible coke formation. The thermal analysis provides the heat transfer rates associated with the individual processes of steam production, gas-phase superheating and reforming necessary to produce 5 kw of electrical power in a PEM fuel cell and allows for the calculation of thermal efficiencies. Then, the chemical reaction pathways for hydrogen production in steam reforming are discussed and the available chemical, adsorption and equilibrium constants are analyzed in terms of thermodynamic consistency. This analysis provides the framework for the reactor sizing and for establishing the adequate operation conditions. (author)

  14. Experimental analysis of a PEM fuel cell 15 W; Analise experimental de uma celula a combustivel PEM 15W

    Miyake, Raphael Guardini; Bazzo, Edson [Universidade Federal de Santa Catarina (UFSC), Florianopolis, SC (Brazil). Dept. de Engenharia Mecanica. Lab. de Combustao e Engenharia de Sistemas Termicos], e-mail: miyake@labcet.ufsc.br, e-mail: ebazzo@emc.ufsc.br

    2006-07-01

    Fuel cells have been considered a promising alternative for electric energy generation. In order to contribute with the development of this technology, a PEM fuel cell was installed and new experiments were carried out at LabCET (Laboratory of Combustion and Thermal System Engineering). Previous results have shown polarization curves identifying the need of rigorous controlling of humidification temperature of the fuel cell. In this paper, new results were carried out considering the use of a fan connected to the fuel cell and possible degradation in the electrolyte, after a relative long time operation. New polarization curves were plotted for comparison with previous results. (author)

  15. O modelo de pseudogestação em camundongos para o estudo 'in situ' das celulas Natural Killer uterinas

    Juares Ednaldo Romero Bianco

    2006-01-01

    Resumo: Durante o período peri-implantacional na gestação de humanos e roedores, ocorre no estroma da mucosa uterina um conjunto de fenômenos que envolvem modificações dos componentes celulares e da matriz extracelular. Este conjunto de modificações é conhecido como decidualização ou reação decidual. Concomitante a este processo ocorre a migração de leucócitos provenientes de órgão hematopoéticos para este estroma. Dentre estes leucócitos predominam as subpopulações de linfócitos denominados ...

  16. Studies of water electrolysis in polymeric membrane cells; Estudos de eletrolise aquosa em celulas de membrana polimerica

    Oliveira-Silva, M.A.; Linardi, M.; Saliba-Silva, A.M. [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil). Centro de Celulas a Combustivel e Hidrogenio

    2010-07-01

    Hydrogen represents great opportunity to be a substitute for fossil fuels in the future. Water as a renewable source of hydrogen is of great interest, since it is abundant and can decompose, producing only pure H{sub 2} and O{sub 2}. This decomposition of water can be accomplished by processes such as electrolysis, thermal decomposition and thermochemical cycles. The membrane electrolysis has been proposed as a viable process for hydrogen production using thermal and electrical energy derived from nuclear energy or any renewable source like solar energy. In this work, within the context of optimization of the electrolysis process, it is intended to develop a mathematical model that can simulate and assist in parameterization of the electrolysis performed by polymer membrane electrolytic cell. The experimental process to produce hydrogen via the cell membrane, aims to optimize the amount of gas produced using renewable energy with non-carbogenic causing no harm by producing gases deleterious to the environment. (author)

  17. Interaccion de promastigotes de Leishmania donovani con celulas de exudado peritonial de ratones mediante la influencia de la quimotripsina

    Lucila Arcay

    1986-06-01

    Full Text Available Se hace un estudio de la interacción de promastigotes de Leishmania donovani con células de exudado peritoneal de ratón (c e p mediante la influencia de la quimotripsina. La adhesión de los promastigotes a las c e p fue terminal y marginal, y en observaciones hechas a partir de los 10 minutos de enfrentamiento, esta adhesión fue nula hasta los 30 minutos en el grupo tratado, y sólo a las das horas hubo un pequeño incremento (2.4% con respecto al control. Se observa marcada disminución en todos los parámetro medidos, tales como enlace, penetración, multiplicación intracelular, división de formas flageladas, en el grupo tratado. La quimotripsina favorece la formación de formas intermedias flageladas, heciendose el parásito piriforme y esférico, apareciendo una forma aberrante de extremo anterior cilindrico que semeja a una forma coanoflagelada. Se sospecha que la enzima reduce efectivamente fragmentos proteicos o péptidos, los cuales pueden haber sido tan pequeños como para esconder a otros ligandos relacionados con la adhesión macrófago-parásito.

  18. IGF-II Y LA GONADOTROPINA CORIONICA REGULAN LA PROLIFERACION, MIGRACION E INVASION DE CELULAS DE TROFOBLASTO HUMANO.

    Ricardo Julian Cabezas-Perez

    2011-01-01

    Full Text Available Son conocidas las propiedades del factor de crecimiento similar a la insulina IGF-II y de la hormona Gonadotropina Coriónica (hCG en la implantación y migración trofoblástica, sin embargo los mecanismos a través de los cuales ejercen sus efectos no han sido identificados. El objetivo de este estudio fue establecer la interacción potencial entre los efectos funcionales de hCG y el IGF-II en la regulación de la proliferación, migración e invasión trofoblástica. Utilizando la línea celular HTR-8/SVneo de trofoblasto extravelloso se pudo demostrar que tanto IGF-II como hCG estimulan la proliferación y migración celular sin observarse efectos aditivos en sus acciones, lo cual es indicativo independencia de sus mecanismos. En contraste, la capacidad invasiva del trofoblasto fue regulada por IGF-II y hCG, dando como resultado efectos aditivos o un potencial sinergismo entre las dos hormonas. En conclusión, nuestros resultados muestran la existencia de interacciones entre las acciones biológicas de IGF-II y hCG en la regulación de la capacidad invasiva de células trofoblásticas y contribuyen al entendimiento de la biología del trofoblasto y de su malignización.

  19. INTEGRACION DE UNA CELULA FLEXIBLE DE MECANIZADO, DE TIPO DOCENTE INTEGRATION OF A EDUCATIONAL FLEXIBLE MANUFACTURING CELL

    Abraham Farias F

    2007-04-01

    Full Text Available Este trabajo trata sobre la integración de una célula flexible de mecanizado de tipo docente, compuesta por una fresadora didáctica CNC, marca Denford, un brazo robótico articulado de seis ejes, modelo Scorbot -ER Vplus  y un riel deslizante; todos pertenecientes al Laboratorio de Manufactura Integrada por Computador, de la Escuela de Ingeniería Mecánica de la Universidad de Talca. Las tareas que realiza esta célula flexible son controladas por un PC director  a través de un  programa, utilizando el software y el propio control del robot y su objetivo es realizar el ciclo de carga y descarga de un  trozo de material de 65×65×40 mm. (madera y su posterior mecanización. El problema de comunicación entre los equipos involucrados y la fresadora CNC fue resuelto en cuanto su diseño "stand alone" no contemplaba la integración con otros equipos. Por otro lado, se agregaron algunos sistemas electroneumáticos para que la operación fuera automática, como los de sujeción de piezas y la apertura y cierre de puertas. Con esta célula flexible de mecanizado de tipo docente, la facultad de Ingeniería cuenta con una plataforma básica, a la que se puede adicionar otras funciones, como por ejemplo, dotarla de un sistema automático de alimentación de piezas, de un sistema de visión digital para dar más autonomía al robot, incorporar un torno CNC y  generar un programa para administrar las órdenes de trabajo.This paper describes the integration of an educational flexible manufacturing cell, consisting of a Denford CNC mill with six axes, and a Scorbot - ER Vplus robotic arm that slides along a rail. This equipment is located at the Computer Integrated Manufacture Laboratory, at the School of Mechanical Engineering at Universidad de Talca. The flexible cell is controlled by software in a PC that interacts with the software in the robotic arm. The specific tasks described in this paper are loading and unloading a wooden piece (640×65×40 and to mechanizing the piece. One difficulty solved in this work was the potential communication problem between the control equipment CNC mill, since the original, stand-alone design did not admit integration with other controllers. In addition, electro-pneumatic devices were added to permit automatic operation of the system in situations such as gripping the piece and opening the mill door. This basic platform gives the possibility of adding new functions and equipment, such as automatic loading of work pieces, digital reading systems, a CNC lathe and a work order information system.

  20. Perovskites synthesis for solid oxide fuel cells; Sintese de perovsquitas para celulas a combustivel de oxido solido

    Soares, Sibelle F.C.X.; Melo, Dulce M.A.; Pimentel, Patricia M.; Melo, Marcus A. Freitas; Martinelli, Daniele M.H. [Universidade Federal do Rio Grande do Norte (UFRN), Natal, RN (Brazil). Dept. de Quimica]. E-mail: sibelle.cunha@gmail

    2008-07-01

    This work aims to study on the obtaining powders of lanthanum manganite oxides with partial substitution of La with strontium at 20% for the application as a cathode for solid oxide fuel cell, through a route of synthesis that are similar to the Pechini method, in which gelatin replaces the ethylene glycol as polymerization agent. The method highlights itself due to its simplicity, low cost and capability to obtain crystalline powders with the high purity and good stoichiometric control. The perovskite obtained were characterized by thermogravimetric analysis, X ray diffraction, electronic scanning microscopy and the superficial area by BET method. The deposition of the perovskite on electrolyte/anode system was done through the spin coating technique. The methodology used for the perovskite synthesis was very efficient, considering a monophasic material was obtained and with characteristics that were proper to the application as electrode to solid oxide fuel cells. (author)

  1. Fuel cell: new electrocatalysts for SOFC (Solid Oxide Fuel Cells) anodes and regulation between cell performance and catalytic activity; Celula a combustivel: novos eletrocatalisadores para anodos de SOFC (Celulas a Combustivel de Oxido Solido) e correlacao entre desempenho da celula e atividade catalitica

    Boaventura, Jaime S.; Aguiar, Aurinete B.; Brandao, Soraia T. [Universidade Federal da Bahia (UFBA), Salvador, BA (Brazil); Frank, Maria Helena Troise; Campos, Michel F. [PETROBRAS, Rio de Janeiro, RJ (Brazil)

    2004-07-01

    Electro-catalysts were prepared using new routes. Chemical Ultrasound Deposition (CUD) method: aqueous solution of nickel nitrate and citric acid was ultrasound vaporized and deposited on heated Ytria-stabilized Zirconia (YSZ). Resin impregnation (IPR) method: nickel oxide and YSZ were mixed, added to phenolic resins, precipitated in acidic water and milled. Wet impregnation method (IMP) was used for comparison: YSZ and an aqueous solution of nickel nitrate and citric acid were mixed, followed by evaporation, drying and calcination. The catalysts were evaluated for methane steam reforming in a quartz reactor. The reactions were conducted for one hour with no significant catalytic activity loss. In reactions with 100 mg of catalyst and a mixture consisting of methane and steam (3:1), IPR catalyst showed activity higher and better stability than those by IMP. On other tests, the reform was conducted with 100 mg of catalyst and methane to steam of 10. The IPR catalyst activity was so high that the reaction approached equilibrium conditions. Anode/electrolyte/cathode units (A/E/C) were prepared with the above catalysts as follows: the anode was a catalyst porous layer; the electrolyte an YSZ dense layer; and the cathode an LSM porous layer; graphite powder formed the material porosity. The two first layers, in powder form, were put in a stainless steel cast, pressed to 4000 bars and sinterized. The cathode layer was subsequently added using tape-casting techniques followed by sintering. A/E/C units showed 40% linear contraction and porosity higher than 20%. For fuel cell tests, A/E/C was mounted in alumina plates with platinum current collectors. Unitary SOF cells were loaded with hydrogen diluted in nitrogen showing opened circuit voltage from circa 700 mV, for the CUD anode, to 350 mV, for the IPR anode. The unitary SOFC was loaded with methane for 15 minutes or longer, with no noticeable voltage loss. At 1300 K the SOFC made with IPR or IMP catalysts showed opened current voltages close to 500 mV, while CUD SOFC measured less approximately 300 mV. In conclusion, the SOFC opened current voltage might be related to the reforming activity of the electro-catalyst used as the anode. (author)

  2. Performance of direct ethanol and methanol fuel cells as function of alcohol concentration applied to the anode of those cells; Desempenho de celulas a combustivel com alimentacao direta de etanol (CCADE) e celulas a combustivel com alimentacao direta de metanol (CCADM) em funcao da concentracao do alcool aplicado ao anodo destas celulas

    Belchor, P.M.; Forte, M.M.C. [Universidade Federal do Rio Grande do Sul, Porto Alegre, RS (Brazil); Correa, J.P.; Kuhn, C.K.; Carpenter, D. [FURB -Fundacao Universidade Regional de Blumenau, SC (Brazil)

    2010-07-01

    This paper aimed to compare the performance of a CCADE and a CCADM as function of diminishing of concentration of alcohol applied top the anode of each cell. As result, reaching a diminishing the concentration of each alcohol through the mix of each one with the deionized water, one obtained a improved humidification and sensible reduction of the permeability of cationic membrane, generating a gain of performance of the functioning both cells. (author)

  3. Una perspectiva de los problemas éticos derivada de la investigación biológica: los avatares del evolucionismo

    Castrodeza, Carlos

    1999-02-01

    Full Text Available Not available.En la ciencia actual, el comportamiento ético es una práctica asumida. Es más, la ética como dimensión axiológica del conocimiento está relacionada con otros valores que le colocan al hombre en la cúspide de los seres vivos, confiriéndole así un derecho de uso sobre toda otra forma de vida. Ahora bien, dichos valores son cuestionables en cuanto que no son compatibles con el conocimiento biológico actual. Dicha falta de coherencia se ejemplifica en la influyente obra —en su día y en la actualidad— El Azar y la Necesidad de Jacques Monod. Estas ideas se contrastan con el pensamiento sociobiológico de los últimos tiempos. De este modo, se ilustra y subraya cómo en toda relación biológica mínimamente simbiótica todo ser vivo intenta romper a su favor la relación contractual subyacente mediante el engaño y, asimismo, intenta detectar el engaño potencial en su interlocutor, pretensión que se da tácitamente por supuesta. De manera que la única doctrina ética acorde con el conocimiento bioevolucionista actual sería un «altruismo recíproco vigilado».

  4. Alternativas ecotecnológicas en la depuración de aguas residuales derivadas de la acuicultura y la producción animal

    González Salas, R.; Romero Cruz, O.; Vidal del Río, M.; Ponce-Palafox, J.T.

    2010-01-01

    Water bodies have increasingly got polluted in the last years due to unappropriate management of wastewaters having urban, industrial and agricultural origen, especially in less Developer nations. Development of ecotechnological alternatives through the use of aquatic plants such as Lemna sp. allows making use of natural resources and thus purify high contaminating loads that are produced by cattle raising and agricultural refuses, generating at the same time large amounts of b...

  5. Detección de aneurisma de la aorta abdominal en una población derivada para ecocardiografía transtorácica

    Clotilde S. Berensztein

    2006-01-01

    Full Text Available Se evaluó: 1 la factibilidad de realizar una ecografía limitada a la aorta abdominal en pacientes a quienes se indica un ecocardiograma transtorácico, 2 las variables clínicas y ecocardiográficas que se correlacionan con el diámetro de la aorta abdominal, 3 la prevalencia de aneurisma de la aorta abdominal (AAA y 4 los factores de riesgo clínicos para AAA. Se evaluaron prospectivamente 280 pacientes consecutivos (media de edad: 68, rango 18 a 93 años, 118 de sexo masculino [42%]. Se verificó que: 1 el examen ecográfico de la aorta abdominal es factible en la mayoría de los pacientes (95,36% [IC 95% 92,88-97,84%], 2 el diámetro de la aorta abdominal se correlaciona con el sexo masculino, la edad, los antecedentes personales de enfermedad vascular periférica y los antecedentes de familiares de primer grado con AAA; también se correlaciona con el diámetro de la raíz aórtica (RA y con el grosor parietal relativo (GPR, 3 existe una prevalencia alta de AAA en la población estudiada (4,49% [IC 95% 1,99-7,00%], particularmente en los varones = 65 años (12,33% [IC 95% 4,60-20,05%] y 4 el sexo masculino, la hipertensión arterial, la dislipemia, el tabaquismo, la diabetes, los antecedentes personales de cardiopatía isquémica o de vasculopatía periférica y los antecedentes de familiares de primer grado con AAA son factores de riesgo para AAA. En conclusión, estaría justificada la realización de una ecografía abdominal como extensión de la ecocardiografía transtorácica en varones = 65 años, en particular si coexisten otros factores de riesgo para AAA.

  6. Concesión de explotación de granitos derivada del permiso de investigación “Honor de Miengo”

    Pozo Gallardo, Julia Ángela

    2014-01-01

    Este proyecto tiene por objeto el estudio de la viabilidad, tanto económica como técnica, de la apertura y explotación de una cantera de granito para su uso como roca ornamental. Para ello se ha seleccionado una zona de potencial interés en Santa Olalla del Cala (Huelva) debido a los afloramientos y la tonalidad de los mismos. En esta zona se ha realizado un estudio del medio físico y una investigación sobre los tipos de roca existentes en la superficie que comprende el Permiso de Investigaci...

  7. PERCEPCIÓN DE ALIMENTOS EN EL PRIMER LUSTRO DE VIDA: ASPECTOS INNATOS, CAUSALIDAD Y MODIFICACIONES DERIVADAS DE LA EXPERIENCIA ALIMENTARIA

    Alejandro Chacón Villalobos

    2011-01-01

    Full Text Available Este trabajo de revisión bibliográfica describe el concepto de la percepción sensorial innata de los niños y niñas hacia los alimentos, así como los procesos por medio de los cuales esta se modifica y enriquece a través de la interacción y las experiencias alimentarias durante el primer lustro de vida. Además, la importancia del marco afectivo y social en el que este proceso formativo se da. Tanto los espacios y contextos donde se consumen y se promocionan los alimentos durante la edad preescolar, el grado de disciplina impuesta, y el nivel de autodeterminación permitido a los menores tienen, en conjunto, un impacto que perdura a lo largo de toda la vida del ser humano. Por ello, la adecuada gestión de las experiencias sensoriales orientadas a generar improntas positivas en el hogar y en el aula, es de gran importancia para educadores y padres de familia por igual. La neofobia y la aversión a los alimentos, así como el rol de los medios de comunicación, son también abordadas complementariamente.

  8. Efecto de células madre mesenquimales derivadas de cordón umbilical sobre el crecimiento y desarrollo tumoral

    Martínez, Marina; Palma, M. B.; Fernández, N. A.; Miriuka, Santiago Gabriel; Luzzani, Carlos; Andrini, Laura; Inda, Ana María; Errecalde, Ana Lía; García, Marcela

    2016-01-01

    Las células madres mesenquimales (CMM) obtenidas de la gelatina de Wharton de cordón umbilical (CMMCU) poseen propiedades similares a las obtenidas desde otras fuentes. Por otro lado, el desarrollo y crecimiento tumoral presenta la necesidad de un desarrollo angiogénico importante a fin de proveer las necesidades metabólicas del tejido. Para ello, las células tumorales expresan el principal inductor, el factor de crecimiento de endotelio vascular (VEGF). Las CMM son un importante componente d...

  9. Tensiones académicas derivadas de los mecanismos de contratación. El caso de la Universidad Autónoma de Querétaro

    María del Carmen Díaz Mejía

    2013-01-01

    entre los académicos que buscan legitimarse jerárquicamente. El problema derivado de tensiones no admitidas deteriora las relaciones entre el cuerpo profesoral y dificulta la mejora de la calidad educativa.

  10. AISLAMIENTO, CARACTERIZACIÓN Y POTENCIAL DE DIFERENCIACIÓN DE CÉLULAS MADRE MESENQUIMALES CANINAS DERIVADAS DE TEJIDO ADIPOSO

    N. B. Riaño

    2014-01-01

    Full Text Available Se caracterizaron células obtenidas del tejido adiposo subcutáneo de caninos para demostrar su naturaleza de células madre mesenquimales (ad-MSCs. Las células se cultivaron y expan - dieron bajo condiciones in vitro . Se determinó la presencia de marcadores de superficie CD73, CD90 y CD105 por citometría de flujo y PCR en tiempo real, siendo idéntico el perfil de expresión obtenido al reportado en células madre mesenquimales humanas. Se demostró su potencial de diferenciación mediante análisis de expresión génica por PCR en tiempo real luego de inducirlas a procesos de diferenciación osteogénica y adipogénica. La capacidad de diferenciación osteogénica se evidenció a través de la expresión de genes de tejido óseo (colágeno tipo I y osteonectina en una cinética de expresión concordante con los eventos moleculares y celulares del desarrollo óseo in vivo . El potencial adipogénico se evaluó por la formación de vacuolas lipídicas intracelulares y la expresión del gen de lipoprotein-lipasa, acorde con el proceso in vivo . Se concluye que las células mesenquimales obtenidas del tejido adiposo de caninos cumplen los criterios morfológicos, de expresión de marcadores de superficie espe - cíficos y de capacidad de diferenciación mesodérmica, confirmando su naturaleza de células madre mesenquimales. Los resultados del presente trabajo indicaron que las ad-MSCs de los caninos son un excelente modelo preclínico para el desarrollo de aplicaciones en medicina regenerativa, tanto en medicina veterinaria, como en medicina humana.

  11. Desempeño productivo de pollos de engorde suplementados con biomasa de saccharomyces cerevisiae derivada de la fermentación de residuos de banano

    Medina, N. M.; González, C. A.; Daza, S. L.; Restrepo, O.; Barahona Rosales, R.

    2014-01-01

    El objetivo de esta investigación fue evaluar el efecto de la inclusión de diferentes niveles de biomasa de levaduras producidas al fermentar hidrolizados de residuos de la industria bananera sobre los parámetros zootécnicos de pollos de engorde, evaluando además el impacto económico de su uso en las dietas. El estudio se realizó en el Centro Agrario San Pablo de la Universidad Nacional Sede Medellín. Se utilizaron 210 pollos de engorde de un día de edad, distribuidos completamente al azar en...

  12. DESEMPEÑO PRODUCTIVO DE POLLOS DE ENGORDE SUPLEMENTADOS CON BIOMASA DE Saccharomyces cerevisiae DERIVADA DE LA FERMENTACIÓN DE RESIDUOS DE BANANO

    N. M. Medina

    2014-01-01

    Full Text Available El objetivo de esta investigación fue evaluar el efecto de la inclusión de diferentes ni-veles de biomasa de levaduras, producidos al fermentar hidrolizados de residuos de laindustria bananera, sobre los parámetros zootécnicos de pollos de engorde, evaluandoademás el impacto económico de su uso en las dietas. Se utilizaron 210 pollos de en-gorde de un día de edad, distribuidos completamente al azar en cinco tratamientos,en una relación de seis réplicas por tratamiento y siete pollos por réplica. El periodoexperimental comprendió 42 días; el alimento y el agua se dispensaron a voluntad. Lasdietas experimentales fueron: T1- Control negativo sin levadura, T2- Control positivocon levadura comercial a razón de 1,5 kg ton-1de alimento, T3- Levadura experimentala razón de 0,5 kg ton-1de la dieta, T4-Levadura experimental a razón de 1,0 kg ton-1de la dieta y T5- Levadura experimental a razón de 1,5 kg ton-1de la dieta. Se observómayor consumo de acumulado alimento en el tratamiento 4 (1kg ton-1de levadura conrespecto a los demás tratamientos evaluados. No hubo diferencias significativas (P>0.05en las otras variables evaluadas en el estudio. Se constató beneficio económico con el usodel tratamiento 4 pues se obtuvieron mejores retornos (precio de venta del pollo – costode la alimentación que fueron mayores a los observados en los tratamientos 1, 2, 3 y 5en 153, 82, 62 y 161 pesos($ ave-1, respectivamente.

  13. Diferenciação de células-tronco mesenquimais derivadas do tecido adiposo em cardiomiócitos

    Pablo Herthel Carvalho

    2013-01-01

    Full Text Available FUNDAMENTO: O potencial de renovação e proliferação dos cardiomiócitos, in vivo, é pequeno, e por isso, o músculo cardíaco apresenta limitada capacidade de repor células perdidas. Na tentativa de minimizar os danos oriundos de lesões hipóxico-isquêmicas e daquelas que acometem o sistema de condução do coração, a terapia celular com células-tronco mesenquimais (MSC vem sendo utilizada, inclusive com cardiomiócitos diferenciados a partir de MSC. OBJETIVO: O presente trabalho comparou três protocolos distintos de indução de diferenciação objetivando a sugestão de um método viável para a diferenciação de maior número de células funcionais que expressem fenótipo cardiomiogênico. MÉTODOS: Culturas de MSC obtidas de tecido adiposo de ratos jovens da linhagem Lewis transgênicos para proteína verde fluorescente (GFP foram submetidos a três diferentes meios de diferenciação cardiogênica: Planat-Bérnard, 5-azacitidina e meio Planat-Bérnard + 5-azacitidina e observadas quanto a expressão de marcadores celulares cardíacos. RESULTADOS: Nos três protolocos utilizados observou-se formação da proteína alfa-actinina sarcomérica no citoesqueleto das células submetidas à diferenciação, expressão de conexina 43 na membrana nuclear e citoplasmática e formação de gap junctions, necessárias para a propagação do impulso elétrico no miocárdio, contudo, em nenhum protocolo foi observada contração espontânea das células submetidas à diferenciação cardiogênica. CONCLUSÃO: A indução com 5-azacitidina proporcionou diferenciação celular cadiomiogênica efetiva e similar à encontrada com o meio Planat-Bénard e, por ser um protocolo mais simples, rápido e com menor custo torna-se o método de eleição.

  14. El concepto de derivada y el modelo de Van Hiele en estudiantes de licenciatura en matemáticas e informática de la Universidad

    Edwin Giovanni Rodríguez-Pérez

    2015-01-01

    Full Text Available There was realized a charectization of the levels geometric reasoning of Van Hiele,applied to the concept of derivate in a sample of 40 students of defferential, integral and multivaried calculation of study master’s plan mathemathics and computer sciencie of the University Francisco de Paula Santander, in which it is discribed, determines and compares the different opposing levels, the realized investigation showed that it’s possible to apply

  15. Calculation methods of reactivity using derivatives of nuclear power and Filter fir; Metodos para o calculo da reatividade usando derivadas da potencia nuclear e o filtro FIR

    Diaz, Daniel Suescun

    2007-07-01

    This work presents two new methods for the solution of the inverse point kinetics equation. The first method is based on the integration by parts of the integral of the inverse point kinetics equation, which results in a power series in terms of the nuclear power in time dependence. Applying some conditions to the nuclear power, the reactivity is represented as first and second derivatives of this nuclear power. This new calculation method for reactivity has special characteristics, amongst which the possibility of using different sampling periods, and the possibility of restarting the calculation, after its interruption associated it with a possible equipment malfunction, allowing the calculation of reactivity in a non-continuous way. Apart from this reactivity can be obtained with or without dependency on the nuclear power memory. The second method is based on the Laplace transform of the point kinetics equations, resulting in an expression equivalent to the inverse kinetics equation as a function of the power history. The reactivity can be written in terms of the summation of convolution with response to impulse, characteristic of a linear system. For its digital form the Z-transform is used, which is the discrete version of the Laplace transform. In this method it can be pointed out that the linear part is equivalent to a filter named Finite Impulse Response (Fir). The Fir filter will always be, stable and non-varying in time, and, apart from this, it can be implemented in the non-recursive way. This type of implementation does not require feedback, allowing the calculation of reactivity in a continuous way. The proposed methods were validated using signals with random noise and showing the relationship between the reactivity difference and the degree of the random noise. (author)

  16. Clonación, expresión y caracterización de una nueva esterasa derivada de metagenomas de suelos agrícolas colombianos

    Carolina Villamil; Patricia Del Portillo; Alvaro Monguí

    2016-01-01

    El presente trabajo tuvo como objetivo la bioprospección de ADN metagenómico derivado de comunidades microbianas asociadas a un agroecosistema de importancia nacional. Este análisis permitió realizar la producción, expresión, purificación y caracterización de una enzima novedosa con actividad esterasa. Esta enzima, denominada LipM, había sido previamente identificada en clones metagenómicos derivados de suelos dedicados al cultivo de papa criolla (Solanum pureja), mediante secuencia de nueva ...

  17. Clonación, expresión y caracterización de una nueva esterasa derivada de metagenomas de suelos agrícolas colombianos

    Carolina Villamil

    2016-07-01

    Full Text Available El presente trabajo tuvo como objetivo la bioprospección de ADN metagenómico derivado de comunidades microbianas asociadas a un agroecosistema de importancia nacional. Este análisis permitió realizar la producción, expresión, purificación y caracterización de una enzima novedosa con actividad esterasa. Esta enzima, denominada LipM, había sido previamente identificada en clones metagenómicos derivados de suelos dedicados al cultivo de papa criolla (Solanum pureja, mediante secuencia de nueva generación y análisis bioinformáticos. La secuencia codificante de la enzima fue clonada en el vector pBADgiii y expresada en E. coli como sistema de expresión, lo que permitió optimizar el proceso de producción recombinante y su posterior purificación. Funcionalmente la enzima presentó una mayor afinidad por sustratos de p-nitrofenil con ácidos grasos de cadena corta (

  18. Medio ambiente, el trabajo y su interfaz frontal de Protección del Trabajador exposición derivada de Riesgos Manejo de nanomateriales

    Flávia de Paiva Medeiros de Oliveira

    2016-06-01

    Full Text Available La frecuente utilización de nanomaterialess en la industria de alimentación, cosméticos, combustibles, causa riesgo a la salud humana que todavía no son conocidos. La inexistencia de certeza científica sobre los posibles males que tales partículas generan no puede ser utilizada como un factor de permisividad para que estos materiales sean manipulados sin la observancia de un grado mínimo de protección cuya finalidad deberá ser siempre la tutela de la vida, salud y dignidad del trabajador. En el intercambio entre el Derecho Ambiental y el Derecho del Trabajo, lo que se pretende proponer es una nueva interpretación del instituto jurídico de la insalubridad como fundamento para la elaboración de una norma capaz de garantizar la salubridad del ambiente de trabajo en lo cual se utiliza partículas nano. A título de conclusión, también la necesidad de redefinición del papel de los sindicatos, que deberán cumplir su responsabilidad socio ambiental para promocionar y defender la salud de sus trabajadores y además participar efectivamente de la tutela del ambiente externo al entorno productivo.

  19. Determinación fenotípica de subpoblaciones de células madre derivadas de sangre de cordón umbilical.

    Viviana Marcela Rodríguez

    2006-03-01

    Full Text Available Introducción. La sangre de cordón umbilical humana es una alternativa para la obtención de células madre hematopoyéticas; sin embargo, no es clara la expresión conjunta de los antígenos CD34, CD38 y HLA-DR, ni de antígenos embrionarios asociados con este tipo de muestra. Objetivos. Determinar la expresión en membrana de los antígenos CD34, CD38 y HLA-DR, así como de los antígenos embrionarios SSEA-4 (Specific Stage Embryonic Antigen?4 y CD13. Materiales y métodos. El estudio se realizó en muestras de sangre de cordón umbilical obtenidas de ochenta mujeres en estado de gravidez normal a término que asistieron al servicio de ginecobstetricia del Hospital Universitario San Ignacio. Los antígenos se determinaron mediante citometría de flujo. Resultados. El rango de células CD34+ presentes en sangre de cordón umbilical humana fue mayor al 0,2% (p=0,0010: a partir de esta población el rango de CD34+/ D38-/ HLA-DR- fue de 0,0153% a 0,0234%, de CD34+/CD38+/HLA-DR- fue de 0,0191% a 0,296%, de CD34+/ CD38-/HLA-DR+ fue de 0,0427% a 0,0676%, y de CD34+/CD38+/HLA-DR+ fue de 0,2427% a 0,5117%. La expresión de los antígenos embrionarios SSEA-4 y CD13 se determinó con el mismo método y se encontraron ocho muestras positivas para la expresión de estos antígenos. Conclusiones. El fenotipo que se expresa con mayor frecuencia en sangre de cordón umbilical corresponde a CD34+ CD38+ HLA DR+; además, el hallazgo de antígenos embrionarios podría indicar que en sangre de cordón umbilical humana existen poblaciones celulares con fenotipos similares a los progenitores celulares adultos multipotentes (Multipotent Adult Progenitor Cells descritos en médula ósea.

  20. Activities of the Radiological Environmental Division related to the Fukushima accident; Actuaciones de la Division de Medio Ambiente Radiologico derivadas del accidente de Fukushima

    Navarro, T.; Gasco, C.; Robles, B.; Montero, M.

    2011-07-01

    The recent Fukushima accident has shown that the scientific community and the general public is very much interested in and concerned about knowing the possible current and future consequences that an accident of this nature can have in both the local population and the rest of the world. It also reveals that society, even though it is not directly affected, feels that it is affected and demands not only fast, effective responses from national authorities, but also a greater involvement of all international bodies related to Nuclear Safety and to Radiological Protection of the public and the environment and a better coordination between them. (Author)

  1. Painéis de partículas provenientes de rejeitos de Pinus sp. tratado com preservante cca e resina derivada de biomassa

    Marília Silva Bertolini

    2014-04-01

    Full Text Available A utilização do preservante CCA (sais de cromo, cobre e arsênio tem sido questionada devido ao impacto relacionado à dispersão, principalmente, do cobre e do arsênio para o ambiente, antes de sua completa fixação na madeira. Outra questão se relaciona à disposição indevida dos resíduos provenientes da madeira tratada, viabilizando a lixiviação devido à maior área passível desses rejeitos sujeita a tal fenômeno. Este trabalho teve como objetivo a produção de painéis de partículas, avaliando o efeito da adição de resíduos de Pinus sp. tratado com sais de cromo, cobre e arsênio (CCA, em associação com material da mesma espécie sem preservantes, além de alterações no teor de adesivo poliuretano à base de mamona empregado na produção. As propriedades dos painéis produzidos foram determinadas conforme recomendações da NBR 14810-3: 2006. Por meio de análise estatística, observou-se que a adição da madeira tratada proporcionou desempenho superior no inchamento em espessura (2 h, ao passo que esse insumo utilizado na mesma proporção que a madeira sem preservantes foi significante, obtendo os melhores resultados na adesão interna. Os módulos de ruptura e de elasticidade na flexão não sofreram influência das variações nos insumos utilizados nos painéis. Os painéis, em grande parte, apresentaram-se em conformidade com os principais requisitos nesse âmbito, mostrando a possibilidade da utilização dos referidos insumos na produção, além da obtenção de um produto com considerável apelo ambiental.

  2. Expresión de las moléculas del Complejo Mayor de Histocompatibilidad clase II y moléculas co-estimuladoras en carcinomas orales in vitro

    Villarroel, Mariana; Speight, Paul M.; Barrett, A. William

    2005-01-01

    El descubrimiento de que el epitelio escamoso estratificado que cubre la mucosa oral podia expresar moleculas del Complejo Mayor de Histocompatibilidad clase II en varias condiciones patologicas de tipo inflamatorio abrio la posibilidad de que los queratinocitos orales sean celulas inmunologicamente activas, las cuales pueden funcionar con .celulas presentadoras de antigenos'ñ. Para una efectiva activacion de los linfocitos T, las celulas presentadoras de antigenos requie...

  3. Implementation of a photovoltaic/electrolyzer/fuel cell autonomous system; Implementacao de um sistema autonomo fotovoltaico/eletrolisador/celula a combustivel

    Silva, Ennio Peres da; Apolinario, Fernando Rezende; Furlan, Andre Luis [Universidade Estadual de Campinas (IFGW/UNICAMP), SP (Brazil). Inst. de Fisica Gleb Wataghin. Lab. de Hidrogenio], Emails: lh2ennio@ifi.unicamp.br, rezende@ifi.unicamp.br; Souza, Rubem Cesar Rodrigues [Universidade Federal do Amazonas (UFAM), Manaus, AM (Brazil). Centro de Desenvolvimento Energetico Amazonico], Email: rubem_souza@yahoo.com.br; Pinto, Adailton de Souza [Centrais Eletricas do Norte do Brasil S.A. (ELETRONORTE), Brasilia, DF (Brazil)], Email: adailton@eln.gov.br

    2006-07-01

    This article presents a project whose main objective is to analyze the technical feasibility of using a system based on the production of hydrogen (H{sub 2}) for storing the energy generated for photovoltaic systems. The work involves the design, physical implementation and the performance evaluation of a system for hydrogen electrolytic generation with solar-photovoltaic energy, the treatment os gas, its storage and it use in fuel cell systems. This work will be performed in cooperation between researchers from the Laboratorio de Hidrogenio (LH2) of the UNICAMP and of the Centro de Desenvolvimento Energetico Amazonico (CDEAM) of the UFAM, and is financing by ELETRONORTE.

  4. Modelling and essay or the polarization curve of a polymeric membrane fuel cell; Modelagem e ensaio da curva de polarizacao de uma celula a combustivel de membrana polimerica

    Almeida, Silvio Carlos Anibal de; Xavier, Bruno Domont; Gatti, George Cassani; Ribeiro, Rodrigo Minguita [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Coordenacao dos Programas de Pos-graduacao de Engenharia (COPPE). Programa de Engenharia Mecanica]. E-mails: silvioa@gmail.com; brunodomont@gmail.com; gatti_ufrj@yahoo.com.br; rminguita@yahoo.com.br; Furtado, Jose Geraldo de Melo [Centro de Pesquisas de Energia Eletrica (CEPEL), Rio de Janeiro, RJ (Brazil). Dept. de Tecnologias Especiais]. E-mail: furtado@cepel.br

    2006-07-01

    This paper describes the essays performed with a polymeric membrane fuel cell (PEMFC) at the test laboratories of the ELETROBRAS Electric Energy Research Center (CEPEL/ELETROBRAS) manufactured by the Eletrocell, which allows to study the influence of some functional parameters (voltage, current, mass and pressure fluxes)

  5. Analysis of cogeneration system using fuel cell: cases study; Analise de sistema de cogeracao utilizando celula de combustivel: estudo de casos

    Silveira, Jose Luz; Leal, Elisangela Martins [UNESP, Guaratingueta, SP (Brazil). Escola de Engenharia. Dept. de Energia]. E-mails: joseluz@feg.unesp.br; elisange@feg.unesp.br

    2000-07-01

    In this paper, a methodology for the study of a molten carbonate fuel cell cogeneration system associated to an absorption refrigeration system, for the electricity and cold water production, and applied to two establishments, is presented. This system permits the recovery of waste heat, available between 600 deg C e 700 deg C. Initially, some technical information about the most diffusing types of the fuel cell demonstration in the world are presented. In the next step, an energetic, exergetic and economic analysis are carry out, seeking the use of fuel cells, in conditions of prices and interest of Brazil. In conclusion, the fuel cell cogeneration system may have an excellent opportunity to strengthen the decentralized energy production in the Brazilian energy scene. (author)

  6. Fuel cell: Brazil is focusing the energy of the millennium; Celula a combustivel: Brasil se prepara para a energia do milenio

    Bombana, Clarice [Eletricidade Moderna (EM), Sao Paulo, SP (Brazil)

    2001-10-15

    The fuel cell is characterized as an important way of distributed energy generation, in this direction it can contribute for solution of demand control problems in relation to critical charging periods or energy rationing. Besides other benefits, can be highlighted the silent operation, utilization of residual heat and high quality of produced energy. Attentive to this tendency, COPEL and LACTEC have united efforts in order to diffuse this technology in Brazil.

  7. Cogeneration, micro turbines and fuel cells: perspectives for distributed generation in Brazil; Cogeracao, microturbinas e celulas a combustivel: perspectivas para geracao distribuida no Brasil

    Leite, Marco Antonio Haikal [PETROBRAS, Rio de Janeiro, RJ (Brazil). Centro de Pesquisas (CENPES)

    2004-07-01

    Brazil has a large potential to install distributed generation systems, using natural gas or renewable like solar, wind or biomass energy. Regarding urban centers, natural gas fired cogeneration and other distributed energy technologies find economical applications. Cogeneration is defined as the generation of two kinds of useful energy from a single energy source. Usually, electrical energy and thermal energy as steam or hot water are produced. By using the absorption refrigeration cycle, chilled water can also be produced to be used in air conditioned systems, often called tri generation, a good alternative to industries, commercial buildings, shopping centers, hospitals, schools and universities. Micro turbines find utilization whenever natural gas is available, but not electricity, like gas compression installations, unmanned platforms or remote production fields. Fuel cells are used in systems requiring high levels of reliability or wherever the non availability cost is high. This paper describe technical and economical data related to PETROBRAS Research Center (CENPES) 3,200 kW electric energy and 1,000 RT chilled water cogeneration system, 200 kW fuel cell and 30 kW and 60 kW microturbines. (author)

  8. Polypropylene (PP) based proton exchange membrane for use in fuel cell; Obtencao de membrana trocadora de protons para uso em celula a combustivel, a base de polipropileno (PP)

    Zen, Heloisa Augusto

    2008-07-01

    The radiation-induced graft of styrene onto polypropylene (PP) films was carried out by simultaneous irradiation method in a cobalt-60 source. The PP films were immersed in a solution of styrene with toluene (1:1 and 4:1, v/v) under inert atmosphere and at room temperature and then submitted at 20, 40, 80 and 100 kGy. After graft reaction the films were kept at room temperature under inert atmosphere for periods of 7, 14, 21 and 28 days in order to evaluate the degree of grafting. At the end of each period the films were sulfonated to provide the hydrophilic property to PP. The degree of grafting (DOG) was gravimetric determined and the chemical changes in the grafted and sulfonated films were characterized by Infrared Spectroscopy, Thermogravimetric Analysis (TGA), Differential Scanning Calorimetry and the Ion Exchange Capacity (IEC) was calculated. The greatest DOG was obtained after 21 days of post-irradiation. By TGA the grafted films exhibited a decrease in the thermal stability, while the sulfonated exhibited an increase. By DSC was possible to verify that matrix polymeric did not suffer any drastic change in the melting temperature after grafting and sulfonation reactions. The IEC calculated shows that the new membrane developed has ionic conductivity property. (author)

  9. Desmoplastic small round cell tumor: a case report and review of the literature; Tumor desmoplastico de pequenas celulas: relato de caso e revisao da literatura

    Pinto, Luiz Gustavo Teixeira [Hospital e Maternidade Marieta Konder Bornhausen, Itajai, SC (Brazil). Servico de Medicina Interna; Isberner, Rony Klaus [Hospital e Maternidade Marieta Konder Bornhausen, Itajai, SC (Brazil). Servico de Radiologia]. E-mail: ronyklaus@terra.com.br; Scolaro, Bruno Lorenzo [Universidade do Vale do Itajai, SC (Brazil). Curso de Medicina]. E-mail: brunoscolaro@yahoo.com.br; Sezerino, Daniel Oseias [Universidade do Vale do Itajai, SC (Brazil). Curso de Medicina. Disciplina de Anatomia Patologica; Almeida, Daniel da Silva [Hospital e Maternidade Marieta Konder Bornhausen, Itajai, SC (Brazil). Servico de Radiologia e Diagnostico por Imagem

    2006-10-15

    Desmoplastic small round cell tumor is a rare and highly aggressive neoplasm that predominantly occurs in young adult males. Pain and abdominal distention are frequent, ascites could be observed. His histogenesis is uncertain and the most common location is the peritoneal cavity. This tumor is characterized by presenting a distinct morphology and polyphenotypic differentiation. We present in this report the case of an adolescent admitted in the service of Internal Medicine and Radiology of the Hospital and Maternity Marieta Konder Bornhausen, Itajai, SC, Brazil, in year 2005. (author)

  10. Technological study of experimental proton exchange polymer membrane fuel cells; Estudo tecnologico de celulas a combustivel experimentais a membrana polimerica trocadora de protons

    Santoro, Thais Aranha de Barros

    2004-07-01

    Experimental studies to achieve an optimized behavior of a unit PEM-fuel cell with an active area of 25cm{sup 2} were carried out. Polarization curves, surface response methodology and regression methodology were used for the analysis. The different methodologies identified the interactions between the parameters that were studied. These parameters were, humidifying temperature, fuel cell operating temperature and the flows of hydrogen and oxygen. MEAs were produced by the spray and hot pressing hybrid method, developed at IPEN. The studies were done with these MEAs and equivalent commercial ones. The MEAs producing method used induced an important variation on the quantity of platinum in the electrodes. This fact has showed to have a great influence in the results. The optimized values were: oxygen flow from 30 to 35% of consume (70 to 65% of excess), fuel cell operating temperature from 60 to 62 deg C and 0.41 mg of platinum in the electrodes. The hydrogen flows and the humidifying temperature have not showed a major influence in the fuel cell behavior, in the studied variable range. (author)

  11. Characterization and improvement gas diffusion layer of low temperature fuel cell; Caracterizacao e aprimoramento da camada difusora de celulas a combustivel de funcionamento a baixa temperatura

    Ramos, C.Z.; Dantas, R.; Oliveira, I.S. de; Azevedo, C.M.N.; Pires, M. [Pontificia Univ. Catolica do Rio Grande do Sul (PUC-RS), Porto Alegre, RS (Brazil). Faculdade de Quimica; Canalli, V. [Pontificia Univ. Catolica do Rio Grande do Sul (PUC-RS), Porto Alegre, RS (Brazil). Faculdade de Engenharia

    2006-07-01

    In low temperature fuel cells the main part is the membrane electrode assembly (MEA). The gas diffusion layer is a component of the MEA, being a composite material constituted by carbon powder and polytetrafluoroethylene, used to increases hydrofobicity, fundamental characteristic in water transport into system. In this work methods were adapted with the aim to a better characterization of the diffusion layer by the measuring the following parameter: contact angle and hysteresis; morphology, thickness and porosity. From these characterization results optimized MEAS will be produced to better fuel cell performance. (author)

  12. DE LA MENTE A LA CELULA: IMPACTO DEL ESTRES EN PSICONEUROINMUNOENDOCRINOLOGIA/ FROM THE MIND TO THE CELL: THE IMPACT OF STRESS ON PSICONEUROIMMUNOENDOCRINOLOGY

    Manolete S. Moscoso*

    2009-10-01

    Full Text Available Resumen:El presente artículo revisa el concepto del modelo psicobiosocial presentado por Engel y los primeros estudios sobre lanueva ciencia de la psiconeuroinmunoendocrinología, publicados por Solomon en la década del 60', y Ader en la década del70'. Se hace mención a los avances modernos en tecnología médica y de laboratorio como el punto de partida de un extensonúmero de estudios multidisclinarios durante la década del 80' que demuestran la relación entre el cerebro, y los sistemasnervioso, endocrino e inmune en el desarrollo de enfermedades. Se hace un análisis del concepto actual del estrés y unabreve revisión de las respuestas emocional y fisiológica descritas por Lazarus, Cannon, Selye, respectivamente. Una nuevavisión acerca del estrés es presentada y se hacen las distinciones correspondientes en relación a la respuesta comportamentaldel estrés, estilo de vida, y el estrés crónico. Finalmente se discute brevemente acerca del impacto negativo del estréscrónico sobre la salud del individuo.Abstarct:This article reviews the biopsicosocial model provided by Engel and the first studies in the field ofpsychoneuroimmunoendocrinology published by Solomon during the 60's and Ader during the 70's. it is pointed out thatadvances in medical technology and laboratory facilitated the beginning of studies in this field during the 80's. Extensivedata reports conclusive evidence of the interconnections between the brain, the nervous, endocrine and immune systems andthe development of disease. We discussed the emotional and physiological responses to stress as described by Lazarus,Cannon, and Selye. A new vision about stress is presented, taking into account the behavioral response to stress, life style,and chronic stress. Finally, we discussed briefly about the negative impact of chronic stress on health.

  13. DE LA MENTE A LA CELULA: IMPACTO DEL ESTRES EN PSICONEUROINMUNOENDOCRINOLOGIA/ FROM THE MIND TO THE CELL: THE IMPACT OF STRESS ON PSICONEUROIMMUNOENDOCRINOLOGY

    Manolete S. Moscoso*

    2009-01-01

    Resumen:El presente artículo revisa el concepto del modelo psicobiosocial presentado por Engel y los primeros estudios sobre lanueva ciencia de la psiconeuroinmunoendocrinología, publicados por Solomon en la década del 60', y Ader en la década del70'. Se hace mención a los avances modernos en tecnología médica y de laboratorio como el punto de partida de un extensonúmero de estudios multidisclinarios durante la década del 80' que demuestran la relación entre el cerebro, y los sistemasnervioso...

  14. Preparation of PVDF and PTFE membranes for fuel cell use; Preparacao de membranas de PVDF e PTFE enxertadas e sulfonadas para uso em celula a combustivel

    Geraldes, Adriana N.; Zen, Heloisa A.; Ferreira, Henrique P.; Parra, Duclerc F.; Lugao, Ademar B.; Linardi, Marcelo [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)], e-mail: angeral@ipen.br

    2007-07-01

    Grafting of styrene onto polyvinylidenefluoride (PVDF), polytetrafluoroethylene (PTFE) was studied using styrene/toluene solutions. First, PTFE and PVDF films were prepared and the process was conducted by radiation induced graft polymerization of styrene, by a Co{sup 60} source. Films of PTFE and PVDF were immersed in styrene/toluene at 1:1 (v/v) concentration and then submitted to gamma radiation at 20 kGy doses. After irradiation, the samples were evaluated at the period of 21 days at room temperature in order to observe the grafting degree. Chemical changes in the PVDF and PTFE films after styrene grafting were monitored and the results were evaluated by FTIR, DSC, TGA and degree of grafting (DOG). The ion exchange capacity (IEC) after sulfonation of 1, 2 and 24 hours were also determined. (author)

  15. Development of perovskite cathodes for solid oxide fuel cells (SOFC); Desenvolvimento de catodos de perovskitas para celula a combustivel solido de eletrolito solido (SOFC)

    Perez, J. [UNESP, Araraquara, SP (Brazil). Inst. de Quimica], e-mail: joelma@iq.unesp.br; Pereira, J.T.; Saeki, M.J. [UNESP, Bauru, SP (Brazil). Faculdade de Ciencias

    2006-07-01

    Solid Oxide Fuel Cells (SOFC) are energy conversion systems of great interest for industrial applications because they present a high efficiency for energy generation and several advantages for the environment. In this work, perovskite type oxides La{sub 085}Sr{sub 0,15}MnO{sub 3}, La{sub 0,7} Sr{sub 0,3}MnO{sub 3}, La{sub 0,6}Sr{sub 0,4}MnO{sub 3}, La{sub 0,85}Sr{sub 0,15}CoO{sub 3}, La{sub 0,7}Sr{sub 0,3}CoO{sub 3}, La{sub 0,6}Sr{sub 0,4}CoO{sub 3}, La{sub 0.6}Sr{sub 0,4}Fe{sub 0,8}Co{sub 0,2}O{sub 3} e La{sub 0.6}Sr{sub 0,4}Fe{sub 0,4}Co{sub 0,6}O{sub 3} were prepared by a polymeric method with the purpose of using them as cathodes in SOFCs. The electrochemical cell was mounted utilizing YSZ (ZrO{sub 2} - 8 mol%Y{sub 2}O{sub 3}) disks as electrolyte, where a paste containing Pt was calcined onto one face while the other one was covered with the oxide materials synthesized ('screen printing'). The oxide materials prepared were characterized by X-ray diffraction, transmission electronic microscopy and thermogravimetry. The oxygen reduction reaction was studied by taking polarization curves in oxygen and/or air (800 deg C a 950 deg C). The best performance was obtained for 15 {mu}m thickness electrodes La{sub 0.6}Sr{sub 0,4}MnO{sub 3} and La{sub 0.6}Sr{sub 0,4}MnO{sub 3} with addition of dispersed Pt. (author)

  16. Fabrication and tests of anode supported solid oxide fuel cell; Fabricacao e testes de celula a combustivel de oxido solido suportada no anodo

    Florio, D.Z. de [UNESP, Araraquara, SP (Brazil)], e-mail: dzflorio@ipen.br; Fonseca, F.C.; Franca, Y.V.; Muccillo, E.N.S.; Muccillo, R. [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Berton, M.A.C.; Garcia, C.M. [LACTEC - Instituto de Tecnologia para o Desenvolvimento, Curitiba, PR (Brazil)

    2006-07-01

    A laboratory setup was designed and put into operation for the development of solid oxide fuel cells (SOFCs). Ceramic single cells were fabricated by low-cost methods, and emphasis was given to the use of ready available raw materials. The whole project consisted of the preparation of the component materials - anode, cathode, and electrolyte - and the buildup of a hydrogen leaking-free sample chamber with platinum leads and current collectors for measuring the electrochemical properties of single SOFCs. Anode-supported single SOFCs of the type (ZrO{sub 2}:Y{sub 2}O{sub 3} + NiO) anode / (ZrO{sub 2}:Y{sub 2}O{sub 3}) electrolyte / (La{sub 0.65}Sr{sub 0.35}MnO{sub 3} + ZrO{sub 2}:Y{sub 2}O{sub 3}) cathode have been prepared and tested at 700 deg C and 800 deg C after in situ H{sub 2} anode reduction. The main results show that the slurry coating method resulted in single-cells with good reproducibility and reasonable performance, suggesting that this method can be considered for fabrication of SOFCs. (author)

  17. Study of PtNi/C catalyst for direct ethanol fuel cell; Estudo do catalisador PtNi/C para celula a combustivel de etanol direto

    Moraes, L.P.R. de; Silva, E.L. da; Amico, S.C.; Malfatti, C.F., E-mail: eticiaprm@gmail.com [Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS (Brazil)

    2014-07-01

    In this work, PtNi binary catalyst and pure platin catalyst were synthesized by the impregnation-reduction method, using Vulcan XC72R as support, for direct ethanol fuel cells. The composition and structure of the catalysts were analyzed by X-ray diffraction, the electrochemical behavior was evaluated by cyclic voltammetry and morphology of the catalysts was studied by high-resolution transmission electron microscopy. The results showed that the addition of Ni to Pt led to the contraction of the crystal lattice, increased the catalytic activity compared to pure Pt and initiated the electrooxidation of ethanol at lower potential. (author)

  18. Hybrid membranes PVA/silicon for use in fuel cells; Membranas hibridas de PVA/silica para aplicacao em celula a combustivel

    Aguiar, Liz C.V. de; Almeida, Raquel D. de; Gomes, Ailton de S. [Universidade Federal do Rio de Janeiro - UFRJ, Instituto de Macromoleculas Professora Eloisa Mano - IMA, RJ (Brazil)], e-mail: lizcontino@ima.ufrj.br; Ramos Filho, Florencio G. de [Centro Universitario Estadual da Zona Oeste - UEZO, Rio de Janeiro, RJ (Brazil)

    2011-07-01

    Hybrids organic-inorganic membranes PVA-silica have been prepared using sol-gel process in situ with the objective of study the influence of inorganic particles incorporation on the water uptake, pervaporation and proton conductivity of PVA membranes. The silica was constituted of mercaptopropyltrimethoxysilane (MPTMS) with or without the mixture with the tetra ethoxysilane (TEOS). The hybrids membranes were oxidated to convert the -SH groups in -SO{sub 3}H groups, becoming them proton conducting. The hybrids membranes not oxidated showed lesser water uptake and pervaporated material, probably, due to the formation of crosslink that restricted the swell of the PVA membrane. The protonic conductivity of the hybrid membranes after the oxidation was up to 26 times bigger than of the membrane not oxidated. (author)

  19. Platinum catalysts recovery of the proton exchange membrane fuel cell; Recuperacao de catalisadores de platina da celula a combustibel de membrana polimerica trocadora de protons

    Fukurozaki, S.H.; Seo, E.S.M. [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil). Centro de Ciencia e Tecnologia de Materiais. Lab. de Processamento de Residuos

    2006-07-01

    Currently, platinum is the most feasible catalyst for the Proton Exchange Membrane Fuel Cells - PEMFC. Along with platinum's significant importance in this energy system are the high cost of this noble metal and its detrimental effects on the environment. Therefore, recycling this material seems as an alternative to decrease its impacts on the environment and, at the same time, to provide a reduction of the system's costs. A search was conducted for literature and studies about platinum recycling methods. However, only two techniques of platinum recovery, which are still in development, were found. In face of this situation, a recovery method of platinum from deactivated Membrane Electrode Assembly - MEA's was developed, with attention to aspects related to the environment and the necessary requirements for its primary recycling. The results found showed a high recovery ratio and a possibility to reintroduce this metal into the production cycle. (author)

  20. Synthesis, characterization and electrical properties of solid electrolyte for solid oxide fuel cell; Preparacao, caracterizacao e propriedades eletricas de eletrolito solido para celula a combustivel de oxido solido

    Berton, Marco Antonio Coelho; Garcia, Carlos Mario; Matos, Jeferson Hrenechen [Instituto de Tecnologia para o Desenvolvimento (LACTEC), Curitiba, PR (Brazil)], Emails: felsky@latec.org.br, garcia@latec.org.br, jeferson.h@latec.org.br

    2010-04-15

    Solid electrolytes of BaCe{sub 08}Gd{sub O29} were prepared by the polymeric precursor method. X-ray diffraction data shows a single phase with orthorhombic crystalline structure. The densification process was followed by scanning electronic microscopy and apparent density measurements. The apparent density was developed for different temperatures of sintering, reaching > 96% for sintered temperature of 1550 {sup 0}C deg . The electrochemical impedance analysis was development in the temperature of 400-700 deg C, in air atmosphere at 700 deg C a value of 30,6 mS.cm{sup -1} was obtained. The results of conductivity have confirmed the gadolinium doped barium cerate has a great potential for use as solid electrolyte for intermediate temperature solid oxide fuel cell, at experimental controlled conditions. (author)

  1. Wind, photovoltaic and fuel cell energy for communication stations; Energia eolica, fotovoltaica e de celula a combustivel para estacoes de comunicacao

    Sousa, Iolanda; Pereira, Jose; Alcobia, Hernani [Net Plan Telecomunicacoes e Energia, Lisboa (Portugal); Pereirinha, Paulo [Instituto Politecnico de Coimbra (Portugal); Instituto para Engenharia de Sistemas e Computadores de Coimbra (Portugal)

    2011-10-15

    This paper presents a hybrid system that provides power to a remote and autonomously telecommunications station by means of electrical solar generators, wind and hydrogen fuel cell. In the absence of sufficient sun and wind, a bank of batteries and hydrogen produced on-site guarantee the power supply. The station can still be remote monitored and managed.

  2. Direct methanol fuel cells: Pt-Ni/C binary electrocatalysts; Celulas a combutivel de metanol direto: eletrocatalisadores binarios de Pt-Ni/C

    Salgado, Jose Ricardo Cezar; Antolini, Ermete; Santos, Ana Maria dos; Gonzalez, Ernesto Rafael [Universidade de Sao Paulo (USP), Sao Carlos, SP (Brazil). Inst. de Quimica], e-mail: salgado@iqsc.usp.br

    2004-07-01

    Direct methanol fuel cells use platinum alloys as more efficient catalysts than platinum. In the case of binary alloys, the second metal affects several properties of platinum, like the interatomic distance, the electronic density and the capacity of forming oxygenated species at lower potentials. In this work, Pt-Ni catalysts supported on high surface area carbon (Pt-Ni/C) were prepared and characterized, and tested as catalysts in the anode and the cathode in direct methanol fuel cells. In both cases the performance of the material was better than that of Pt/C, and comparing the two situations it was better when the material was used in the cathode. The improved performance in the cathode was attributed to the nickel that forms a true alloy with platinum, while the better performance in the anode was attributed to the presence of nickel oxides. (author)

  3. Manganates of lanthanum and strontium as cathode of fuel cells (SOFC); Manganatos de lantanio e estroncio como catodo de celulas combustiveis (SOFC)

    Macedo, Marfran C. de; Nascimento, Rubens M. do; Martinelli, Antonio E.; Melo, Dulce M.A. [Universidade Federal do Rio Grande do Norte (UFRN), Natal, RN (Brazil)

    2004-07-01

    The fuel cells if constitute currently as a promising alternative modular generation of electric energy to leave of chemical energy. The SOFCs is distinguished as promising for the industry of the oil, therefore they can use the produced natural gas in the platforms as combustible, allowing generation of raised power electric.The material of cathode constituent of the cell are oxides with perovskites structure, normally doped with a earthy-alkaline element (Sr{sup +3}). In this work, two compositions of the La{sub 1-x}Sr{sub x} MnO{sub 3} system were synthesized (x = 0,15 and 0,30), through the Pechini method and after resultants of the process they were characterized by X- Ray diffraction, Fourier-transform infrared spectroscopy (FTIR), thermal gravimetric analysis (TG/DTG) and laser grain size analysis. The systems in study shown similar behavior how much to the results of absorption in the region of infra-red ray and TG/DTG, therefore if it can prove the loss of organic substance with the increase of the temperature.The average particle diameter for the two systems also increased gradually with the temperature. In general way the synthesis method was satisfactory for the formation of the perovskites phase in the two studied compositions. (author)

  4. Infiltración meningea por leucemia a celulas plasmáticas y por linfoma no Hodgkin: estudio citomorfologico en el liquido cefalo-raquideo

    Arnaldo Tabares Olives

    1982-06-01

    Full Text Available Son presentadas las características citomorfológicas anormales encontradas en el LCR de dos pacientes, uno de ellos sufriendo de leucemia aguda a células plasmáticas y otro de linfoma mixto no Hodgkin. Se enfatiza la importancia del estudio del LCR en estas patologias.

  5. Polyester synthesis for application in PEMFC type fuel cells; Sintese de poliester para aplicacao em celulas a combustivel do tipo PEM

    Fiuza, R.P.; Souza, D.R. de; Fiuza, R.A.; Jose, N.M.; Boaventura, J.S. [Universidade Federal da Bahia (UFBA), Salvador, BA (Brazil). Inst. de Quimica], e-mail: raigenis@gmail.com

    2006-07-01

    The PEMFC (Proton Exchange Membrane Fuel Cell), along the SOFC (Solid Oxide Fuel Cell), is the most important technology, among the various types of fuels cell. The PEMFC shows a large versatility of applications, both for stationary and mobile use. However the PEMFC presents high manufacture cost, directly impacting in the cost of the produced energy. This work contemplates the previews sulfonation of phtalic acid and its subsequent polymerization with glycerol, using as catalytic tin dibutyl-dilaurate. The obtained material has been characterized by DSC, TGA, FTIR, MEV, DRX and XRF. The gotten results indicated that phtalic acid was sulfonated and the increase of the sulfonation degree significantly increased the crystallinity of the sulfonated ftalico acid. Furthermore, the polymer produced from the sulfonated monomer presented adequate thermal resistance and a high content of conducting groups, necessary conditions for application as electrolyte in PEMFC. All these characteristics, particularly the low cost of the reagents and the ease of production process, make the sulfonated polyester membrane a promising candidate as fuel cell electrolyte. (author)

  6. Glow discharge preparation and electrooptical characterisation of amorphous silicon alloys for solar cells. Preparacion por descarga luminiscente y caracterizacion electrooptica de aleaciones de silicio amorfo para celulas solares

    Carabe, J

    1990-11-01

    A study is presented, focused on the preparation and characterisation of hydrogenated amorphous silicon alloy thin films for their application as p type window layers in pin silicon solar cells. The preparation technique used was radio frequency glow discharge. The samples were characterised optically (visible, near infrared and infrared absorption spectrophotometry) and electrically (dark and photoconductivities at ambient temperature and as functions of temperature). The influence of each of the preparation parameters on film properties has been systematically studied. The results have been analysed according to the existing models. Chapter 1 is an introduction to the material in question and its photovoltaic applications. Chapter 2 describes the experimental procedure used. Capter 3 shows and discusses the most relevant results obtained in the study of intrinsic amorphous silicon, p type amorphous silicon and p type amorphous silicon carbide window layers, with special emphasis on the influence of the use of an alternative dopant gas: boron trifluoride. Finally, chapter 4 summarises the most relevant conclusions drawn from this research work. (Author)

  7. Radiation therapy for the treatment of feline advanced cutaneous squamous cell carcinoma; A utilizacao da radioterapia no tratamento do carcinoma de celulas escamosas cutaneo felino avancado

    Cunha, S.C.S.; Corgozinho, K.B.; Ferreira, A.M.R, E-mail: simonecsc@gmail.com [Universidade Federal Fluminense (UFF), Niteroi, RJ (Brazil); Carvalho, L.A.V. [Coordenacao dos Programas de Pos-Graduacao em Engenharia (COPPE/UFRJ), RJ (Brazil); Holguin, P.G.

    2014-02-15

    The efficacy of radiation therapy for feline advanced cutaneous squamous cell carcinoma was evaluated. A full course radiation therapy protocol was applied to six cats showing single or multiple facial squamous cell carcinomas, in a total of seven histologically confirmed neoplastic lesions. Of the lesions, one was staged as T{sub 1}, and six as T{sub 4} according to WHO staging system of epidermal tumors. The animals were submitted to twelve radiation fractions of 4 Gy each, on a Monday-Wednesday-Friday schedule, and the equipment used was an orthovoltage unit. Energy used was 120 kV, 15 mA and 2 mm aluminum filter. The cats were evaluated during the treatment and 30 and 60 days after the end of the radiation therapy. In this study, 87% of the lesions had complete remission and 13% partial remission to the treatment. Side effects were considered mild according to Veterinary Radiation Therapy Oncology Group Toxicity criteria, and included erythema, epilation and rhinitis. Radiation Therapy was considered safe for feline cutaneous squamous cell carcinoma, leading to mild side effects and can represent a good therapeutic option. (author)

  8. Stem Cells and Blood: Where have we come from... and where are we going?; Celulas Madre y sangre: De donde venimos y... donde vamos a parar

    Bueren, J. A.

    2011-07-01

    Since 1961, they year when the first trial that characterized the behaviour of a stem cell in mice exposed to high doses of radiation was described, research in this field has proceeded at an unpredictable place. Knowledge of the function of hematopoietic stem cells which are responsible for forming blood cells facilitated the development of therapies based on the transplant of bone marrow and other cell source, e. g. blood from the umbilical cord. These breakthroughs, together with the progress of molecular biology and virology, made it possible to manipulate the genome of hematopoietic stem cells so effectively and safely that the transplant of genetically modified cells has become a variable therapeutic alternative for the treatment of certain genetic diseases and also cancer. This brief article describes some of the contributions that our Hematopoiesis and Gene Therapy Division of the CIEMAT and the CIBER for Rare Diseases has been developing in this fascinating field of stem cells and gene therapy, in the context of the international research being carried out in this area. (Author) 34 refs.

  9. Conductor polymeric membranes with potential for application in PEM type fuel cells; Membranas polimericas condutoras com potencialidades para aplicacao em celulas a combustivel do tipo PEM

    Brioude, Michel de Meireles; Sodre, Livia Farias; Boaventura Filho, Jaime Soares; Jose, Nadia Mamede [Universidade Federal da Bahia (UFBA), Salvador, BA (Brazil)

    2006-07-01

    In this work two series of membranes were prepared; they were based on hybrid organic-inorganic or composite materials and presented potentiality for application in Proton Exchange Membrane Fuel Cell, PEMFC. The polymeric phase was constituted of poly(dimethylsiloxane), PDMS, crosslinked with tetra ethoxysilane, TEOS, with a 70%/30% ratio. Phosphotungstic acid (PWA) or the sodium monododecylsulphate (MDS), as proton conductors, were added to the inorganic network, close to the gel point; the mixtures were transferred to a cast. The films were characterized by infrared spectroscopy (FTIR), X-ray diffraction (XRD), thermogravimetric analysis (TGA) and scanning electron microscopy (SEM). The membranes showed good properties, as flexibility, thermal and mechanical stability with potentiality to be used as conducting membranes in technological applications. (author)

  10. Multi-metallic anodes for solid oxide fuel cell applications; Anodos multi-metalicos para aplicacoes em celulas a combustivel de oxido solido

    Restivo, T.A. Guisard; Mello-Castanho, S.R.H. [Instituto de Pesquisas Energeticas e Nucleares (CCTM/IPEN/CNEN-SP), Sao Paulo, SP (Brazil). Centro de Ciencia e Tecnologia dos Materiais; Leite, D. Will [Instituto de Pesquisas e Estudos Industriais (IPEI/FEI), Sao Bernardo do Campo, SP (Brazil). Fac. de Engenharia Industrial

    2009-07-01

    A new method for direct preparation of materials for solid oxide fuel cell anode - Ni- YSZ cermets - based on mechanical alloying (MA) of the original powders is developed, allowing to admix homogeneously any component. Additive metals are selected from thermodynamic criteria, leading to compacts consolidation through sintering by activated surface (SAS). The combined process MA-SSA can reduce the sintering temperature by 300 deg C, yielding porous anodes. Densification mechanisms are discussed from quasi-isothermal sintering kinetics results. Doping with Ag, W, Cu, Mo, Nb, Ta, in descending order, promotes the densification of pellets through liquid phase sintering and evaporation of metals and oxides, which allow reducing the sintering temperature. Powders and pellets characterization by electronic microscopy and X-ray diffraction completes the result analyses. (author)

  11. Interpenetrating polymer network membranes for fuel cells: infrared vibrational spectroscopy; Membranes baseadas dm redes polimericas interpenetrantes para celulas a combustivel: estudo por espectroscopia vibracional no infravermelho

    Loureiro, Felipe A.M.; Rocco, Ana Maria [Grupo de Materiais Condutores e Energia, Escola de Quimica, Universidade Federal do Rio de Janeiro, RJ (Brazil)], e-mail: amrocco@eq.ufrj.br; Pereira, Robson Pacheco [Instituto de Ciencias Exatas, Universidade Federal Fluminense (UFF), Volta Redonda, RJ (Brazil)

    2011-07-01

    In the present work, proton conductive membranes based on IPN matrices doped with H{sub 3}PO{sub 4} were developed. The characterization by infrared vibrational spectroscopy evidenced the polymerization of DGEBA and the immobilization of PEI chains, originating a structure containing basic sites suitable for proton coordination and conduction. The FTIR characterization evidenced the polymerization of DGEBA in the presence of PEI thus forming Semi-IPN membranes which, after doped with H{sub 3}PO{sub 4}, exhibited conductivity values of 10{sup -4} W{sup -1}cm{sup -1} at room temperature and 10{sup -3} {omega}{sup -1}cm{sup -1} at 80 degree C, as well as a dependency of conductivity with temperature following the Arrhenius model. The activation energy values (14,33 and 12,96 kJ.mol{sup -1}) indicated a proton conduction mechanism predominantly vehicular in the matrices studied under 100% relative humidity. (author)

  12. Photovoltaic network connection portraits (XIV): The issue of hot cells; Retraso de la conexion fotovoltaica a la red (XIV): El asunto de las celulas calientes

    Lorenzo, E.; Martinez, F.; Moreton, R.

    2009-07-01

    In some cases due to plants performance is not as correct as hoped, and in some other, simply because the nice colors of the thermographs resulted very attractive to plenty of people; many photovoltaic generators have been profusely thermography within the current year. It has caused a special interest on hot cells phenomenon, that is to say those cells which operate at a significantly higher temperature than other placed in the same panel. (Author) 4 refs.

  13. Adhesive market develops new technologies. The thin-film solar cells gain ground; El mercado de adhesivos desarrolla nuevas tecnologias. Las celulas solares de capa fina ganan terreno

    Kluke, M.

    2010-07-01

    The solar industry is booming. thin-film technology is experiencing a high demand as promised cost advantages and currently is providing excellent results, while a range of efficiency reaches acceptable. (Author)

  14. Electric power generation using photovoltaic solar cells for low income rural population; Geracao de energia eletrica com celula solar fotovoltaica para populacao rural de baixa renda

    Gastaldi, Andre Fava; Souza, Teofilo Miguel de; Mesquita, Rafael Pimenta [Universidade Estadual Paulista Julio de Mesquita Filho (UNESP), Guaratingueta, SP (Brazil). Centro de Energias Renovaveis], e-mail: teofilo@feg.unesp.br

    2004-07-01

    With the growing electric energy use demand and almost not expansion of the energy mesh (basically composed by hydroelectric plants) existing in the country, several others methods of alternative energy generation may be necessary. Beyond that, the usually employed energy is becoming much more costly, rarer and politically more impracticable like burn fuels as oil and coal. The use of renewable approaches of energy, that are 'infinite' energies (as the wind and the light of the sun, for example), can become an excellent alternative. In this new energy group, the solar energy transformed by the use of photo voltage cells is becoming very important. The 'clear' solar radiation tends to be a more intelligent and practical option, and the future technology of energy storage will be able to solve the problem of the regions that have less sunny days. Its main advantages on the other alternative sources of energy are the trustworthiness and the previsibility. Its biggest disadvantage consists on the fact that technical limitations can not allow a solar energy generator to distribute electricity for a city. It is interesting to notice that with the development of projects as this in alternative energy, isolated areas that does not access electricity distribution network (as some far regions), it has become the most viable option of generation of electric energy. Another point is that even with the distribution network it has to be checked if it is possible to use this electricity consulting the company credential that work at those localities of consumption. Moreover, many regions of the country already installed the solar energy system for water heating, confirming that, the existing structure allows the installation of a a solar cells generation energy system without many problems. In this project, we introduce a method for electric energy generation by solar cells for rural population of low gains. This option uses low cost materials but with a good quality level. Also presents a comparative table showing a kit for rural areas employment which is constituted of: 3 fluorescent light bulbs (power of 9 W, 3 hours per day, 7 days per week), 1 T.V. of 14' ' (power of 15 W, 3 hours per day, 7 days per week) and 1 Radio (power of 5 W, 6 hours per day, 5 days per week). (author)

  15. Dancoff factors of unit cells in cluster geometry with partial absorption of neutrons; Fatores de Dancoff de celulas unitarias em geometria cluster com absorcao parcial de neutrons

    Rodrigues, Leticia Jenisch

    2011-01-15

    In its classical formulation, the Dancoff factor for a perfectly absorbing fuel rod is defined as the relative reduction in the incurrent of resonance neutrons into the rod in the presence of neighboring rods, as compared to the incurrent into a single fuel rod immersed in an infinite moderator. Alternatively, this factor can be viewed as the probability that a neutron emerging from the surface of a fuel rod will enter another fuel rod without any collision in the moderator or cladding. For perfectly absorbing fuel these definitions are equivalent. In the last years, several works appeared in literature reporting improvements in the calculation of Dancoff factors, using both the classical and the collision probability definitions. In this work, we step further reporting Dancoff factors for perfectly absorbing (Black) and partially absorbing (Grey) fuel rods calculated by the collision probability method, in cluster cells with square outer boundaries. In order to validate the results, comparisons are made with the equivalent cylindricalized cell in hypothetical test cases. The calculation is performed considering specularly reflecting boundary conditions, for the square lattice, and diffusive reflecting boundary conditions, for the cylindrical geometry. The results show the expected asymptotic behavior of the solution with increasing cell sizes. In addition, Dancoff factors are computed for the Canadian cells CANDU-37 and CANFLEX by the Monte Carlo and Direct methods. Finally, the effective multiplication factors, k{sub eff}, for these cells (cluster cell with square outer boundaries and the equivalent cylindricalized cell) are also computed, and the differences reported for the cases using the perfect and partial absorption assumptions. (author)

  16. CARCINOMA ODONTOGÉNICO DE CELULAS CLARAS. ESTUDIO CLÍNICO, RADIOLÓGICO Y PATOLÓGICO DE UN CASO.

    Rosaura Rodríguez Flores

    2004-01-01

    Full Text Available Los tumores odontogénicos (TO son un grupo complejo y poco frecuente de neoplasias con características clínicas, radiológicas, histopatológicas y evolución muy variables. El Carcinoma odontogénico de células claras (COCC es una neoplasia maligna, de comportamiento agresivo variable que se presenta en maxilares. Histológicamente se constituye de nidos de células, frecuentemente de citoplasma claro, rico en glucógeno, rodeadas por bandas de colágena. Pertenece al grupo de los tumores odontogénicos epiteliales malignos. Se presenta el caso de un hombre de 57 años con un tumor en hueso y seno maxilar izquierdo, sometido a hemimaxilectomía subtotal izquierda. Los estudios de imagen demostraron una lesión destructiva mixta en maxilar y seno maxilar izquierdo y la histología reveló la imagen clásica de COCC y la inmunohistoquímica mostró inmunoreactividad para Queratina AE1/AE3, EMA y S-100 (focal. Se demostró abudante glucógeno mediante la reacción de PAS en el citoplasma de las células neoplásicas. El paciente ha tenido seguimiento por 5 años y está asintomático después de la cirugía sin tratamiento complementario con radioterapia.

  17. Fora da ordem natural: a natureza nos discursos sobre a clonagem e a pesquisa com celulas-tronco em jornais brasileiros

    Flavia Natercia da Silva Medeiros

    2013-11-01

    Full Text Available Noções de natureza desempenham um papel na cobertura midiática e nas percepções do público sobre as biotecnologias. Neste estudo, fez-se uma análise de discurso das ideias de natureza e natural usadas na cobertura jornalística brasileira da clonagem e das células-tronco. Nos discursos oponentes, as técnicas biotecnológicas foram postas fora da ordem natural e consideradas imorais. Nos discursos defensores, apareceu uma natureza indiferente ou cruel para com o destino humano, ou obstáculo a ser superado; por outro lado, a clonagem e as células-tronco embrionárias foram naturalizadas, e a ovelha Dolly foi antropomorfizada. As representações mitificantes ou transcendentes da natureza não incidem somente sobre as percepções públicas, têm implicações éticas e políticas.

  18. Estudos sobre a regeneração do figado - variação do volume nuclear das celulas hepáticas em repouso divisional

    Fernando Ubatuba

    1948-12-01

    Full Text Available Surgical removal of large amounts of hepatic tissue in male albino rats results in a rapid and conspicuous raise in cellular nuclear volumes. Measurements were made exclusively in resting nuclei. This volume variation is transitory. Nuclear volumes return to the normal value withins 6 days of restoration. The higher value are abserved 48 hours after the hepatic removal, indicating probably that this effect is due to hydration of the nucei, as occurs in the cytoplasm. This hydration could be correlated to the mitotic activity of the renmant tissue since a peak of mitoses parallels the changes in the nuclear volumes.

  19. Establecimiento de un cultivo de celulas en suspensión de Eucalyptus cinérea Establishment of cell suspension culture of Eucalyptus cinerea

    Arias Zabala Mario

    2002-06-01

    Full Text Available Se desarrolla un protocolo para la obtención y establecimiento de suspensiones celulares de E. cinerea. La concentración de las hormonas 2,4 D Y BAP tienen un efecto significativo en la formación de callos friables de E. cinerea, obteniendo una respuesta periódica en la formación de callos friables con respecto a la concentración de las hormonas. Puede obtenerse hasta un 90% de formación de callos friables con varias combinaciones hormonales; primero, con concentraciones alrededor de 3,0 mg/L de 2,4 D Y 1,0 mg/L de BAp, y segundo, alrededor de 6,0 mg/L de 2,4 D Y1,0 mg/L de BAP. A partir de los callos anteriores, se obtienen suspensiones celulares con un activo crecimiento celular, con tiempos de duplicación entre cuatro y siete días, y alcanzando densidades celulares de 15 g células secas/L. Las suspensiones de E. cinerea ofrecen una herramienta importante para la propagación de esta especie vía embriogénesis somática, estudio de biorreactores, producción de metabolitos secundarios y procesos de biotransformación.A protocol is developed for obtaining and establishment of E. cinerea cell suspension. The concentration of hormones 2,4 D and BAP have a significant effect in the formation of friable callus of E. cinerea, obtaining a periodic answer in the formation of friable callus with regard to hormones concentration. It can be obtained until 90% of formation of friable callus in several hormone combinations, first with concentrations around 3,0 mg/L of 2,4 D and 1,0 mg/L of BAP; and second, around 6,0 mgIL of 2,4 D and 1,0 mg/L of BAP. Using the last callus, cell suspensions are obtained with an active cellular growth, with times of duplication between 4 and 7 days and obtaining cell densities of 15 g of dry cells/L. The suspensions of E. cinerea offer an important tool for the propagation of this specie by somatic embryogenesis, bioreactors study, production of secondary metabolites and biotransformation processes.

  20. Unconventional cells of TiO2 doped with erbium; Celulas nao convencionais de TiO2 dopado com erbio

    Ribeiro, P.C.; Campos, R.D.; Oliveira, A.S.; Wellen, R., E-mail: pollyana@cear.ufpb.edu.br [Universidade Federal da Paraiba (UFPB), Joao Pessoa, PB (Brazil); Diniz, V.C.S.; Costa, A.C.F.M. da [Universidade Federal de Campina Grande (UFCG), PB (Brazil). Departamento de Engenharia de Materiais

    2016-07-01

    The technology used in TiO{sub 2} solar cells is in constant improvement, new configurations have been developed, aiming practicality and leading to efficiency increase of photovoltaic devices. This paper proposes a new technology for the production of solar cells in order to investigate a better utilization of solar spectrum of TiO2 doped with erbium (Er{sup 3+}), proven by energetic conversion. The Ti{sub 0,9}Er{sub 0,1}O2 system was obtained by Pechini method. Nanoparticles have a crystallite size 65.30 nm and surface area 118.48 m{sup 2}/g. These characteristics are essential for the formation of the film to be deposited on the conductive glass substrate constituting the cell's photoelectrode. The other side of the cell is the platinum counter electrode. The cell will have the faces sealed by a thermoplastic and, finally the electrolyte will be inserted, then they will be electrically evaluated through energy efficiency and confronted with the literature data base. (author)

  1. Localización inmunocitoquímica de la hormona gonadotropina corionica en la placenta humana y en celulas tumorales

    Geranina Escovar V.

    1982-06-01

    Full Text Available Mediante el uso de los métodos de peroxidasa anti-peroxidasa e inmunofluorescencia aplicada a tejidos desparafinados y tratados con tripsina, se estudiaron inmunocitoquímicamente un grupo de placentas y tumores malignos. Al utilizar anticuerpos anti-GCH, la hormona gonadotropina coriónica humana (GCH fue localizada en células del sincitiotrofoblasto de placentas de diferentes estados de desarrollo, se encontró, además, que las c6lulas de Langhan's y del citotrofoblasto fueron negativas a la inmuno-reacción. La mayoría de los tumores estudiados fueron encontrados positivos al aplicar los métodos mencionados. Se postula que la inmunosupresión selectiva del huésped por tumores y la inmunosupresión selectiva de tejidos maternos por tejidos fetales. podría estar mediada por la hormona gonadotropina coriónica.

  2. Linfoma de celulas B de la zona marginal extraganglionar del tejido linfoide asociado a mucosa (linfoma MALT de pulmón

    Carlos Vergara-Uzcategui

    2014-09-01

    Full Text Available Los Linfomas Pulmonares Primarios son extremadamente raros (0,4% de los linfomas extraganglionares, y generalmente son de tejido linfoide asociado a mucosas (tipo MALT, con ocasionales linfomas de células grandes difusos. Los síntomas son inespecíficos, y casi la mitad de los pacientes son asintomáticos. Se presenta el caso de un paciente masculino de 56 años de edad, quien presentó durante 7 meses accesos diarios de tos seca, de predominio nocturno, asociados en el último mes a fiebre de 39ºC, disnea a medianos esfuerzos y expectoración verduzca. Los exámenes de laboratorio fueron normales. La radiografía de tórax mostró el mediastino ensanchado, un proceso en lóbulo medio con efecto atelectásico, y un nódulo en hemitórax izquierdo. La tomografía computarizada (TC torácica de alta resolución evidenció proceso alveolar derecho en lóbulo medio y un nódulo pulmonar izquierdo calcificado de tipo inespecífico. El estudio inmunohistoquímico de la biopsia pulmonar fue compatible con Linfoma de Células B de la zona marginal extraganglionar del tejido linfoide asociado a mucosa (Linfoma MALT de pulmón. La TC corporal y la Tomografía por Emisión de Positrones (PET evidenciaron importantes hallazgos complementarios para determinar la extensión de la enfermedad. El paciente se trato con quimioterapia y actualmente se encuentra en buenas condiciones, sin recidiva de la sintomatología. Dado lo infrecuente de la patología se presenta este caso y se hace una revisión de la literatura

  3. Contribuição ao desenvolvimento de tecnologia de fabricação de celulas solares utilizando "dopant papers"

    Alexandre Guass Junior

    1995-01-01

    Resumo: Este trabalho teve como objetivo o desenvolvimento de um conjunto de processos de baixo custo para fabricação de células solares. As células solares foram fabricadas utilizando lâminas de silício monocristalino, com orientação cristalografica e resistividade típica de 4.1 à 9.0 ohm.cm, tipo p dopadas com boro. Ajunção n-p foi obtida por difusão usando papéis dopantes. Estes papéis são de dois tipos, os que possuem boro e os com fósforo.A montagem de um conjunto de lâminas de s...

  4. Operating Cell Temperature Determination in Flat-Plate Photovoltaic Modules; Calculo de la Temperature de Operacion de Celulas Solares en un Panel Fotovoltaico Plano

    Chenlo, F.

    2002-07-01

    Two procedures (simplified and complete) to determine the operating cell temperature in photovoltaic modules operating in real conditions assuming isothermal stationary modules are presented in this work. Some examples are included that show the dependence of this temperature on several environment (sky, ground and ambient temperatures, solar irradiance, wind speed, etc.) and structural (module geometry and size, encapsulating materials, antirreflexive optical coatings, etc) factors and also on electrical module performance. In a further step temperature profiles for non-isothermal modules are analysed besides transitory effects due to variable irradiance and wind gusts. (Author)

  5. Technological evaluation of fuel cells using natural gas for distributed power generation; Avaliacao tecnologica da utilizacao de gas natural em celulas a combustivel para geracao distribuida de energia

    Brandao, Mauricio O. [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Coordenacao dos Programas de Pos-Graduacao de Engenharia (COPPE). Programa de Engenharia Mecanica; Giannini, Marcio P.; Arouca, Mauricio C. [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Coordenacao dos Programas de Pos-Graduacao de Engenharia (COPPE). Programa de Planejamento Energetico

    2004-07-01

    The search for sustainable and more rational means of power generation motivates the scientific crew to search for more efficient and cleaner systems. Oil dependence becomes from the kind of development that the humanity had and cannot be dismissed. The question is how to use this source in a more intelligent way. Fuel Cells are electrochemical devices that convert into electric energy the chemical energy from oxi-reduction reactions between a fuel and an oxidant. The current fuel used in a Fuel Cell is hydrogen and oxygen is the oxidant. The great advantage of this device is its efficiency, higher than the one achieved with internal combustion engines. Also Fuel Cells are not limited by Carnot's efficiency. This paper is about the implementation of a distributed generation system using Fuel Cells. Technical aspects are approached together with economical and environmental needs. The already existence of Gas pipelines and the grown production of Natural Gas presented by Brazil turns it into a good market for the implementation of this energy source. The evaluation of this paper shows that is technically possible to use NG in Fuel Cells, mostly in South and Southeast regions, applying the distributed generation of energy concept. The most interesting in a strategic manner is that Brazil already have an indication that it's capable of developing this technology, opening a new market tuning with world's new technological developments. Many research centers develop this technology, not only from the cell composition itself, but also manufacturing techniques. (author)

  6. The utilization of natural gas in the electricity production through fuel cell; A utilizacao do gas natural na geracao distribuida atraves de celulas combustiveis

    Bernardi Junior, Paulo

    2004-07-01

    In function of the necessity of electric energy as input of vital importance for the development of the country, this work aims at to offer plus an energy alternative for Brazil. The exploitation of the natural gas reserves recently discovered can be made through modern methods that give as priority the distributed generation and the low ambient impact. All these aspects can be gotten with the use of fuel cell, working with the remodelled natural gas. Increased to the factor of a low ambient impact in the proper generation, the project suggests that the generating source can be located next the consumer, diminishing still more the problems generated for transmission lines, fuel transport, etc. The fuel cell has received a great attention in the international community and some models, some already in commercial period of training, they have shown excellent possibilities of capsize to be one of the future technologies in the generation of electric energy with low ambient impact. (author)

  7. Hydrogen purification for fuel cells using gold catalysts promoted with copper; Purificacao de hidrogenio para celulas a combustivel utilizando catalisadores de ouro promovidos com cobre

    Mozer, Thiago Simonato; Passos, Fabio Barboza [Universidade Federal Fluminense (UFF), Niteroi, RJ (Brazil). Dept. de Engenharia Quimica e de Petroleo. Lab. de Reatores, Cinetica e Catalise (RECAT)]. E-mail: mozer@vm.uff.br

    2008-07-01

    The selective CO oxidation in the presence of H2 was investigated on Au catalysts promoted with different amounts of Cu. Au catalysts were prepared by the deposition-precipitation method and exhibited a satisfactory activity at 50 deg C with adequate selectivity. The addition of Cu to Au/Al{sub 2}O{sub 3} catalysts caused an increase in the selectivity to CO oxidation due to an interaction between Au and Cu on the surface of the catalysts. However, this beneficial effect was limited to an optimal content of Cu. Through the temperature programmed reduction (TPR) and ultraviolet visible diffuse reflectance spectroscopy (UV-vis DRS) techniques, the formation of small bimetallic Au-Cu particles was verified. The best result was obtained with 2.5% Au-0.5% Cu/Al{sub 2}O{sub 3} catalyst, the CO conversion was higher than 95% and the selectivity was around 70% at 50 deg C. The catalysts showed stable catalytic activity during 24 hours time -on-stream. In the presence of H{sub 2}O and CO{sub 2}, a small decrease in the CO conversion was observed in the stability test, probably due to the deactivation caused by the CO{sub 2} presence. (author)

  8. Snake venoms components with antitumor activity in murine melanoma cells; Componentes derivados de venenos de serpentes com acao antitumoral em celulas de melanoma murino

    Queiroz, Rodrigo Guimaraes

    2012-07-01

    Despite the constant advances in the treatment of cancer, this disease remains one of the main causes of mortality worldwide. So, the development of new treatment modalities is imperative. Snake venom causes a variety of biological effects because they constitute a complex mixture of substances as disintegrins, proteases (serine and metalo), phospholipases A2, L-amino acid oxidases and others. The goal of the present work is to evaluate a anti-tumor activity of some snake venoms fractions. There are several studies of components derived from snake venoms with this kind of activity. After fractionation of snake venoms of the families Viperidae and Elapidae, the fractions were assayed towards murine melanoma cell line B16-F10 and fibroblasts L929. The results showed that the fractions of venom of the snake Notechis ater niger had higher specificity and potential antitumor activity on B16-F10 cell line than the other studied venoms. Since the components of this venom are not explored yet coupled with the potential activity showed in this work, we decided to choose this venom to develop further studies. The cytotoxic fractions were evaluated to identify and characterize the components that showed antitumoral activity. Western blot assays and zymography suggests that these proteins do not belong to the class of metallo and serine proteinases. (author)

  9. Stem-cells used in treatment of periodontal bone defects; Utilizacion de celulas madre en el tratamiento de defectos oseos periodontales

    Perez Borrego, Amparo [Facultad de Ciencias Medicas ' Enrique Cabrera' , La Habana (Cuba); Dominguez Rodriguez, Libia; Ilisastigui Ortueta, Zaida Teresa [Facultad de Estomatologia, La Habana (Cuba); Hernandez Ramirez, Porfirio [Instituto de Hematologia e Inmunologia, La Habana (Cuba)], E-mail: amparop.borrego@infomed.sld.cu

    2009-07-01

    The aggressive periodontitis might to provoke the tooth loss, of its function and to affect the patient's aesthetics. The techniques used for the lost bone regeneration, not always are successful and in occasions are very expensive. For years it is working in tissues regeneration by stem-cells implantation. Periodontium could be a potential for this task. This is a study of a female patient aged 26 with an apparent health status and aggressive periodontitis backgrounds treated from 10 years ago, seen in our service due to dental mobility producing mastication nuisances. At clinical examination we noted systemic chronic inflammation of gums, grade II and III dental mobility in incisives and molars teeth, 4-8 mm systemic periodontal sacs and furcation lesions in inferior molars. At radiographs advanced bone losses and a decrease of systemic bone density are noted. After written consent and the initial preparation, we carried out a periodontal flap in the 35 and 37 teeth zone, where the stem-cells concentrate was placed, in bone defects of superior molars (16-17) and previous radicular scraping and isolation, treatment consisted in stem-cells perfusion without flap. There were not postoperative side effects. At 7 days there was a normal coloration, at three months on noted at radiograph a bone neoformation, and at six months gum remained healthy, with a decrease of dental mobility in segment treated and in the evolutionary radiograph it was evidenced the formation and increase of density.

  10. Estudio de la reaccion de sulfurizacion de precursores Cu/In para la formacion de capas delgadas policristalinas de CuInS2 para celulas solares

    Barcones Campo, Beatriz; Álvarez García, Jacobo; Calvo-Barrio, L.; Pérez Rodríguez, Alejandro; Romano Rodríguez, Alberto; Morante i Lleonart, Joan Ramon; Scheer, R.; Klenk, R.; Pietzker, Ch.

    2004-01-01

    En este trabajo se presenta un estudio detallado de los procesos implicados en la sulfurización de capas metálicas de Cu-In para la fabricación de células solares de CuInS2. Con este objeto, se ha desarrollado un experimento de sulfurización parcial de las capas, que han sido sometidas posteriormente a un tratamiento de selenización. El estudio de estas estructuras mediante Espectroscopía Raman y Espectroscopía de Electrones Auger (AES) ha permitido conocer algunos de los detalles de la reacc...

  11. Emergencia de la resistencia antibiótica debida a las β-lactamasas de espectro extendido (BLEE: detección, impacto clínico y epidemiología

    SALIM< MÁTTAR

    Full Text Available RESUMEN La rápida emergencia de la resistencia antimicrobiana debida a las BLEE tiene un impacto significativo en la salud pública. En los últimos 24 años ha suscitado un gran interés el conocimiento acerca de las BLEE, esta explosión de publicaciones abarca a todos los continentes y más de 30 países, actualmente es motivo de preocupación y se considera un problema de salud pública. Las BLEE son enzimas que producen los gram negativos y confieren resistencia a las penicilinas, a todas las cefalosporinas y al aztreonam, pero no a los carbapenems ni a las cefamicinas y la mayoría son inhibidas por el acido clavulanico. En general las BLEE son derivadas de TEM-1, TEM-2 y SHV-1, difieren entre si de sus progenitoras por unos escasos aminoácidos por lo que su filogenia es cercana. Son comúnmente encontradas en E.coli, Klebsiella sp, y P.mirabilis, no obstante, existen otras BLEE que difieren filogenéticamente de TEM y SHV, como las CTX-M, las carbapenemasas tipo OXA y las metalo-β-lactamasas VIM e IMP, típicamente encontradas en especies de P. aeruginosa, Serratia sp and Enterobacter sp. La producción de BLEE en los patógenos de importancia clínica es un problema serio en los pacientes hospitalizados debido a las implicaciones clínicas, terapéuticas y económicas. Las técnicas para la detección de las BLEE van de lo simple con aspectos fenotipicos hasta las pruebas complejas moleculares de geno-detección específica. El objetivo de esta revisión es discutir el impacto clínico y epidemiológico de las BLEE más prevalentes así como las técnicas para su detección y su seguimiento nosocomial.

  12. Evaluation of the radio modifier effect of propolis on chinese hamster ovary (CHO-K1) and human prostate cancer (PC3) cells, irradiated with 60-CO; Avaliacao do efeito radiomodificador da propolis em celulas de ovario de hamster chines (CHO-K1) e em celulas tumorais de prostata (PC3), irradiadas com CO-60

    Santos, Geyza Spigoti

    2011-07-01

    In the last decades, it has been given a great interest to investigations concerning natural, effective, nontoxic compounds with radioprotective potential together with the increasing utilization of different types of ionizing radiation for various applications. Among them propolis, a resinous compound produced by honeybees (Apis mellifera), has been considered quite promising, since it presents several advantageous biological characteristics, i. e., anti-inflammatory, antimicrobial, anticarcinogenic, antioxidant and also free radical scavenging action. The purpose of the present study was to evaluate the effect of Brazilian propolis, collected in the State of Rio Grande do Sul, on Chinese hamster ovary (CHO-K1) and human prostate cancer (PC3) cells, irradiated with {sup 60}Co {gamma} radiation. For this purpose, three interlinked parameters were analyzed: micronucleus induction, cell viability and clonogenic death. The choice of these parameters was justified by their biological significance, in addition to the fact that they are readily observable and measurable in irradiated cells. The cytogenetic data obtained showed a radioprotective effect of propolis (5-100 {mu}g/ml) in the induction of DNA damage for both cell lines, irradiated with doses of 1 - 4 Gy. The cytotoxicity assay, however, showed a prominent antiproliferative effect of propolis (50 - 400{mu}/ml) in PC3 cells irradiated with 5 G{gamma}. The survival curves obtained were adequately fitted by a linear-quadratic model, where the {alpha} coefficient was higher in CHO-K1 cells. Concerning the clonogenic capacity, PC3 cells were more radiosensitive than CHO-K1 cells at the higher doses of the survival curve. Propolis at the concentrations of 30 - 100 {mu}g/ml, did not influence the clonogenic potential of PC3 cells, since the survival curves, associated or not with propolis, were found similar, although the combined treatment in CHO-K1 cells exhibited a stimulating proliferative effect. The data obtained in vitro showed a potential use of propolis AF-08, a natural and nontoxic compound, in the prevention against the adverse effect of ionizing radiation, at the doses and concentrations here analyzed. (author)

  13. Effects on the work of a direct ethanol fuel cell as function of compacting force applied to the cell; Efeitos no funcionamento de uma celula a combustivel com alimentacao direta de etanol (CCADE) em funcao da forca de compactacao aplicada a celula

    Belchior, P.M.; Forte, M.M.C. [UFRGS - Universidade Federal do Rio Grande do Sul, Porto Alegre, RS (Brazil); Serafin, R.; Fusiger, V.; Carpenter, D. [FURB - Fundacao Universidade Regional de Blumenau, SC (Brazil)

    2010-07-01

    This experiment aimed to verify the influence due to the variation of the compacting force applied to a DEFC. According to the tests, as the increase of cell compacting, the performance improves significantly. According applied tests, when the high electrical conductivity components are used, small differences of the cell compacting can generate a large difference on the total ohmic resistance. Through the tests one can conclude that with the increase of cell compacting, the contact probably increase among the distribution of reagents and the diffuser layer, improving the cell performance. (author)

  14. Estratégias de tratamento da leucemia linfóide crônica recidivada ou resistente incluindo o transplante de célula progenitora hematopoiética Strategies of treatment for relapsed or resistant chronic lymphocytic leukemia including to hematopoietic progenitor cell transplantation

    Cármino A. Souza

    2005-12-01

    Full Text Available Apesar dos importantes progressos terapêuticos, a leucemia linfóide crônica (LLC, a mais comum leucemia do adulto nos países ocidentais, permanece incurável. A utilização da fludarabina isolada ou associada à ciclofosfamida e/ou antraciclínicos elevou de maneira importante as respostas objetivas, inclusive com a obtenção de respostas completas (até mesmo moleculares e as sobrevidas livres de progressão e de recidiva. Alguns autores sugerem a introdução de anticorpos monoclonais para elevar ainda mais estes resultados. Apesar disto, todos os pacientes tratados devem apresentar recidiva ou progressão da LLC e tratamento de salvamento deve ser instituído. No presente momento, as estratégias de tratamento de salvamento são muito semelhantes às disponíveis para o tratamento de primeira linha. Os critérios para se iniciar o tratamento de salvamento são semelhantes aos definidos pelo NCI (National Cancer Institute para o primeiro tratamento. Assim, a utilização de fludarabina, isolada ou associada, deve ser a terapêutica de escolha para os pacientes recidivados, mesmo que tenham sido previamente tratados com fludarabina como primeira linha. A utilização de anticorpos monoclonais, particularmente o rituximab, é desejável nesta segunda tentativa, mesmo que não se possa dizer ainda que esta indicação seja formal. O alemtuzumab é um anticorpo monoclonal muito eficiente e tem mostrado ter a capacidade de promover importantes benefícios clínicos e hematológicos, mesmo em pacientes "pesadamente" tratados ou mesmo refratários à fludarabina. O TCPH tem indicações limitadas tendo em vista os riscos da terapia de alta dose em pacientes que são, geralmente, idosos. Assim, o transplante autólogo pode ser indicado em pacientes jovens, preferentemente em remissão completa, no sentido de prolongar a sobrevida livre de progressão. Os transplantes alogênicos, convencional ou de intensidade reduzida, podem ser utilizados em pacientes com doador HLA idêntico, preferentemente mais jovens (Despite much progress in therapy, chronic lymphocytic leukemia, the most common leukemia in the Western world, remains incurable. The use of fludarabine alone or associated to cyclophosphamide and/or mitoxantrone or doxorubicin improved the objective response, including complete response (also molecular and the progression- and relapse-free-survival. Several authors have suggested the introduction of monoclonal antibodies in order to improve the results. Despite that, all treated patients will further relapse or progress and salvage treatment should be used. In the present state-of-the art, salvage treatment is similar to those used as front line therapy. Indeed the criteria to start treatment are the same as defined by NCI for the front line therapy. Fludarabine alone or associated should be the therapy of choice for relapsed patients also for those previously treated with fludarabine. The use of monoclonal antibodies particularly rituximab is a good option although this procedure has not been considered as the standard therapy until now. Alemtuzumab is a very efficient monoclonal antibody and promotes significant benefits in clinical and hematological responses also in heavily treated or fludarabine refractory patients. The HPCT has limited indication due to the risks of high dose therapy in elderly patients. Autologous HPCT may be used specifically in young patients, if possible in complete remission, in order to improve the progression- or disease-free-survival. Conventional or with reduced intensity allogeneic HPCT may be used in patients presenting with a sibling donor particularly those under 60 years old, in fludarabine refractory patients or in patients presenting with unfavorable cytogenetics (17p-, with a curative objective.

  15. Percepción de los profesionales de la salud sobre las creencias y las tradiciones derivadas del Islam como barreras a la donación de órganos en Argelia

    Nouhad Laidouni

    2017-03-01

    Conclusión: Existe confusión entre la población argelina sobre la postura del Islam en torno a la donación y el trasplante de órganos, que perjudica fundamentalmente a la tasa de donación cadavérica. La colaboración entre el sector sanitario y las figuras religiosas para sensibilizar a la población podría contribuir a mejorar la disposición de la población a donar sus órganos no solo en vida.

  16. Avaliação por RAPD de plantas de abacaxizeiro cultivar Smooth Cayenne derivadas do seccionamento do talo e cultura de tecidos Evaluation of pineapple plants cultivar Smooth Cayenne from peduncle division and tissue culture by RAPD

    MARIA VITÓRIA CECCHETTI GOTTARDI

    2002-04-01

    Full Text Available Foram coletadas, em área comercial da fazenda Córrego dos Bois, município de Canápolis -- MG, plantas de abacaxizeiro cultivar Smooth Cayenne, para serem avaliadas quanto à propagação pelo método do seccionamento do talo e cultura de tecidos, bem como análise por RAPD das mudas decorrentes destes dois processos de propagação. A propagação pelo seccionamento do talo foi eficiente na produção de mudas, tanto em quantidade como em qualidade, em um curto espaço de tempo, além de apresentar a mesma característica genotípica (análise por RAPD das plantas-matrizes de origem. Já no processo de produção de mudas por cultura de tecidos, não foi obtida uma quantidade suficiente de mudas que comprovasse a utilização de uma metodologia mais sofisticada. Além da perda por contaminação em laboratório de 70% do material em estudo, foi necessária a utilização de um longo período, aproximadamente 18 meses, para a obtenção das mudas. Na análise por RAPD das plantas decorrentes deste processo de propagação, foram observados padrões de bandas diferentes em algumas amostras, as quais podem estar relacionadas com uma possível variação somaclonal.Plants of pineapple Smooth Cayenne cultivar were collected from a commercial area, Córrego dos Bois farm, in Canápolis, state of Minas Gerais, to evaluate two different processes of propagation, peduncle division and tissue culture. These same plants were characterized by RAPD analysis. According to the two propagation method, the peduncle division was efficient in seedlings propagation, in quantity as well as in quality, at a short period of time, resulting the same phenotype and genetic characteristics (RAPD analysis from the matrix descent plants. In the tissue culture method, the quantity of seedlings obtained were not good enough that could prove the use of a sophisticated methodology. Besides loosing 70% of the material, it was necessary to expend a long period of time, at least 18 months to obtain the new seedlings. By RAPD analysis of plants obtained by tissue culture were observed different patterns in some samples, those could be related to somaclonal variation.

  17. Geometria da valva mitral derivada da ressonância magnética cardiovascular na avaliação da gravidade da regurgitação mitral

    Andre Mauricio Fernandes

    2013-06-01

    Full Text Available FUNDAMENTO: A regurgitação mitral é a doença valvar cardíaca mais comum em todo o mundo. A ressonância magnética pode ser uma ferramenta útil para analisar os parâmetros da valva mitral. OBJETIVO: diferenciar padrões geométricos da valva mitral em pacientes com diferentes gravidades por regurgitação mitral (RM com base na ressonância magnética cardiovascular. MÉTODOS: Sessenta e três pacientes foram submetidos à ressonância magnética cardiovascular. Os parâmetros da valva mitral analisados foram: área (mm2 e ângulo (graus de tenting, altura do ventrículo (mm, altura do tenting (mm, folheto anterior, comprimento posterior do folheto (leaflet e diâmetro do anulo (mm. Os pacientes foram divididos em dois grupos, um incluindo pacientes que necessitaram de cirurgia da valva mitral e o outro os que não. RESULTADOS: Trinta e seis pacientes apresentaram de RM discreta a leve (1-2+ e 27 RM de moderada a grave (3-4+. Dez (15,9% dos 63 pacientes foram submetidos à cirurgia. Pacientes com RM mais grave tiveram maior diâmetro sistólico final do ventrículo esquerdo (38,6 ± 10,2 vs. 45,4 ± 16,8, p < 0,05 e diâmetro diastólico final esquerdo (52,9 ± 6,8 vs. 60,1 ± 12,3, p = 0,005. Na análise multivariada, a área de tenting foi a determinante mais forte de gravidade de RM (r = 0,62, p = 0,035. Comprimento do anulo (36,1 ± 4,7 vs. 41 ± 6,7, p< 0,001, área de tenting (190,7 ± 149,7 vs. 130 ± 71,3, p= 0,048 e comprimento do folheto posterior (15,1 ± 4,1 vs. 12,2 ± 3,5, p= 0,023 foram maiores em pacientes que precisaram de cirurgia da valva mitral. CONCLUSÕES: Área de tenting, anulo e comprimento do folheto posterior são possíveis determinantes da gravidade da RM. Estes parâmetros geométricos podem ser usados para individualizar a gravidade e, provavelmente, no futuro, orientar o tratamento do paciente com base na anatomia individual do aparelho mitral.

  18. Mechanical and thermal properties of castor oil polyurethane bone cement after gamma irradiation;Propriedades mecanicas e termicas de poliuretanas derivadas do oleo de mamona usadas como cimento osseo depois da irradiacao com radiacao gamma

    Azevedo, E.C. [Universidade Tecnologica Federal do Parana (DF/UTFPR), Curitiba, PR (Brazil). Dept. de Fisica; Soboll, D.S. [Universidade Tecnologica Federal Parana (CPGEI/UTFPR), Curitiba, PR (Brazil); Chierice, G.O.; Claro Neto, S. [Universidade de Sao Paulo (IQSC/USP), Sao Carlos, SP (Brazil). Inst. de Quimica; Lepiesnki, C.M. [Universidade Federal do Parana (DF/UFPR), Curitiba, PR (Brazil). Dept. de Fisica; Nascimento, E.M. [Universidade Tecnologica Federal do Parana (DM/UTFPR), Curitiba (Brazil). Dept. de Mecanica

    2009-07-01

    Polyurethanes from castor oil are being employed as bone cement in medical applications. In this work the thermal and mechanical properties of gamma irradiated polyurethanes derivative from castor oil were investigated by instrumented indentation, thermogravimetry and scanning electron microscopy. A slightly increase in hardness is observed only for doses as high as 100 kGy. Thermal analysis indicates stability at human body temperature. The glass transition temperature has small changes after gamma irradiation. (author)

  19. Las aglomeraciones urbanas y los impuestos: algunas ideas derivadas de la aplicación de la curva de Laffer al impuesto sobre la renta español en diferentes escenarios espaciales

    Laura Varela-Candamio

    2017-01-01

    Full Text Available Antecedentes: La búsqueda de las tasas impositivas óptimas ha sido recurrente en las discusiones de política fiscal. En particular, la relación entre la estructura tributaria y el crecimiento económico ha hecho resurgir la hipótesis de Laffer que implica la existencia de una relación parabólica entre el nivel de impuestos y los ingresos obtenidos. Nuestra hipótesis es que las zonas urbanas tienen un impacto igualmente significativo sobre la disposición a pagar impuestos y puede existir igual o más heterogeneidad entre los tamaños urbanos que entre los dife- rentes territorios. Metodología: En este artículo se contrasta la hipótesis de Laffer para el caso español utilizando microdatos del Instituto de Estudios Fiscales ( IEF para el año 2009 en diferentes escenarios espaciales. Para ello, se utiliza una muestra de declaran- tes de corte transversal estimada con mínimos cuadrados ordinarios. Resultados: La presencia de una relación parabólica entre la carga tributaria y la recaudación de impuestos permite obtener una tasa impositiva que maximiza los ingresos fiscales en torno a 30%, el doble del promedio aplicado. Por regiones, hemos observado variaciones importantes que justifican la existencia de un alto grado de descentralización fiscal. Pero esta variabilidad es también importante según el tamaño de las ciudades. Los ingresos fiscales máximos de las dos princi- pales ciudades, Madrid y Barcelona, se obtienen con una tasa impositiva de 34%, mientras que todas las demás ciudades alcanzan el máximo de ingresos fiscales a tasas similares. Conclusiones: Cuanto menor es el tamaño de la ciudad, menor es la tasa impositiva que maximiza los ingresos fiscales, abriendo una brecha más grande cuanto más pequeña es la ciudad.

  20. Modelos animales y células derivadas para su uso en la determinación de compuestos útiles en el tratamiento de linfomas de células T

    Bustelo, Xosé R.; Ruiz Macías, Sergio; Santos de Dios, Eugenio

    2008-01-01

    [ES] La presente invención se encuadra dentro del campo de la biotecnología. Se refiere a un método para evaluar si un compuesto es efectivo en la prevención y/o tratamiento de una enfermedad asociada a linfomas de células T.

  1. Aplicaciones legales derivadas de la incorporación del software libre en la función pública de los registros y notarías

    Mercedes Villalobos

    2011-05-01

    Full Text Available Desde la entrada en vigencia de la Constitución del año 2000, se persigue el alcance de la autonomía e independencia tecnológica para contribuir al desarrollo económico, social y político del país. Así, se ordenó el uso obligatorio del software libre en la Administración Pública con el fin de promover la prestación oportuna y eficiente de los servicios públicos a medida que la tecnología se vaya incluyendo como un instrumento de dicha labor. Ejemplo de ello es el Ministerio del Poder Popular para Relaciones Interiores y Justicia, que a través del Servicio Autónomo de Registros y Notarías y, la emisión de los decretos y leyes que rigen la correspondiente competencia como el caso del Decreto Presidencial N 3.390 (Presidencia de la República, 2004, se ha implementado la modernización a través de la automatización de los procesos registrales y notariales con el empleo de los medios electrónicos, en donde tiene cabida el software libre. Al respecto ha surgido el interés de trabajar con el objeto de establecer la efectiva aplicación legal de la función pública desarrollada por los Registros y Notarías con la implementación de tal migración informática. Para ello se adoptó una investigación de tipo documental con diseño bibliográfico y el método de observación documental a partir de la Ley del Registro Público y del Notariado (Asamblea Nacional, 2006 y la Ley Orgánica de Registro Civil (Asamblea Nacional, 2009, que regulan la materia registral y notarial en Venezuela, permitiendo obtener resultados a través de una hermenéutica jurídica aplicable en el método de análisis dogmático jurídico; concluyéndose en el conocimiento de los efectos legales que determinaron la esencialidad de las acciones concretas para usar este tipo de software, acordes con los preceptos aplicables a la función pública especificada.

  2. Implementation of rafts of water spillage retention in the NPP. Almaraz and Trillo. Actions arising from the ITC-2; Implantacion de balsas de retencion de vertidos liquidos en las CCNN de Trillo y Almaraz. Actuaciones derivadas de la ITC-2

    Font Hadinger, I.; Fernandez Morales, E.; Lopez Hernandez, A.

    2014-07-01

    In compliance with the ITC-2 of the Consejo de Seguridad Nuclear, have been built rafts for the containment of spills potentially radiologically contaminated, produced within the NPP site. Almaraz and Trillo. These discharges would be caused by certain mitigation activities to deploy in response to events beyond the design basis related to the potential loss of large areas (large fire mitigation and spraying of gaseous emissions) and in addition in the case of CNA, by a potential leak of the SFP (Spent Fuel Pool - pool of spent fuel). The basic idea is that any liquid discharge generated by the previous reasons within the Nuclear island may be content before your arrival to the outside of the plant through its network for the disposal of rainwater. Therefore, these rafts are the barrier last contention against an uncontrolled discharge of these waters to the environment. The same design ensures compliance with all the requirements, normative and practical, ensuring containment of aforementioned wastes potential capacity. (Author)

  3. The sexual and reproductive health of young people in Latin America: evidence from WHO case studies La salud sexual y reproductiva de los jóvenes en América Latina: evidencia derivada de estudios de la OMS

    Kate Kostrzewa

    2008-02-01

    Full Text Available This original article addresses the sexual and reproductive health needs of young people aged 15 to 24 in Latin America. It introduces five articles from original research projects in three countries: Argentina, Brazil, and Peru. These projects were funded by the World Health Organization. This article explains the importance of studies that address the sexual and reproductive health of young people in developing countries. It provides an overview of sexual and reproductive health issues in Latin America and a discussion these issues in the three study countries. The five articles deal with difficult and challenging issues, including: knowledge of STIs and HIV/AIDS; pregnancy related practices; quality of care; the role of young men in couple formation, pregnancy and adoption of contraceptive practice; and, the role of obstetricians and gynecologists in public policy debate about family planning and abortion. The four articles in this special section help to improve our understanding of the factors that contribute to risky sexual behavior and negative reproductive health outcomes among youth in Latin America. The findings are useful to help inform and improve health care interventions in various contexts.Este artículo original trata de las necesidades de salud sexual y reproductiva de jóvenes entre 15 y 24 años de edad en América Latina. Se presentan cuatro artículos derivados de investigaciones originales en tres países: Argentina, Brasil y Perú. Estos proyectos fueron patrocinados por la Organización Mundial de la Salud. Este artículo elucida la importancia de los estudios que tratan de la salud sexual y reproductiva de jóvenes en países en desarollo. Se ilustra el panorama general en cuestiones de salud sexual y reproductiva en América Latina y una discusión de estas cuestiones en los tres países de donde provienen los estudios. Los cinco artículos discuten cuestiones difíciles y controversiales, como los conocimientos sobre ITS y VIH/SIDA; las prácticas asociadas con el parto; la calidad de cuidados; el papel de los hombres jóvenes en la formación de parejas, el embarazo y el uso de métodos anticonceptivos; así como el papel de los tocólogos y ginecólogos en el debate público sobre planificación familiar y aborto. Los cuatro artículos en esta sección especial promueven un mejor entendimiento de los factores que contribuyen a las conductas sexuales de riesgo y a los resultados negativos en salud reproductiva entre los jóvenes en América Latina. Las conclusiones son útiles para informar y mejorar intervenciones de servicios de salud en contextos varios.

  4. Uso de células troncales mesenquimales derivadas de la grasa y plasma rico en plaquetas para el tratamiento preventivo de osteonecrosis de los maxilares relacionada con la toma de bisfosfonatos. Estudio experimental en ratas

    Barba Recreo, Paula

    2018-01-01

    Tesis doctoral inédita leída en la Universidad Autónoma de Madrid, Facultad de Medicina, Departamento de Cirugía. Fecha de lectura: 8-09-2017 La osteonecrosis de los maxilares relacionada con la toma de bisfosfonatos (BRONJ) es una patología de frecuencia creciente, asociada a estos fármacos antirresortivos de amplio uso. El principal reto en el manejo de BRONJ es la ausencia de un tratamiento efectivo establecido. El objetivo de este trabajo fue comparar diferentes tratamiento...

  5. AS DIFERENÇAS ENTRE OS CONCEITOS DE MORAL NO UTILITARISMO DE BENTHAM E JOHN STUART MILL: A MORALIDADE COMO DERIVADA DAS RESPECTIVAS NOÇÕES DE NATUREZA HUMANA

    Maria Cristina Longo Cardoso Dias

    2015-07-01

    Full Text Available O objetivo desse artigo é compreender a diferença entre amoralidade dos sistemas filosóficos de Bentham e John Stuart Mill,bem como provar que há mais espaço para a elaboração de regrasmorais no utilitarismo de Mill, quando comparado ao utilitarismode Bentham. Contudo, para que se entenda como a moral nosistema de Bentham distingue-se da moral no sistema de Mill, énecessário ter uma clara noção da natureza humana dos indivíduosde ambos os autores e dos respectivos princípios de utilidade quederivam destas distintas noções de natureza humana, pois oconceito de moralidade de cada autor decorre das respectivas ideiasde natureza humana e do princípio de utilidade de tais autores.

  6. Algunas implicancias derivadas del régimen de las obligaciones de dar moneda extranjera del artículo 765 del Código Civil y Comercial de la Nación

    Juan José Greco

    2015-09-01

    Full Text Available Tras haber realizado un análisis crítico del régimen de las obligaciones de dar moneda extranjera del Código Civil y Comercial de la Nación, encontramos inconveniente haberles quitado el carácter de dinerarias. En consecuencia, creemos que debe hacerse una interpretación coherente y armónica con todo el ordenamiento, y por tanto, en el caso de que existan institutos con regímenes especiales debe primar su aplicación. Además, entendemos que la facultad del deudor de liberarse entregando el equivalente en moneda de curso legal es supletoria de la voluntad de las partes, siempre y cuando no se viole la prohibición de indexar. En los casos en que proceda tal atribución sería pertinente para calcular el valor de cambio, acudir a mecanismos que respeten el valor real de la moneda extranjera.

  7. A System for the Feedback of Experience from Events in Nuclear Installations. Safety Guide (Spanish Edition); Un sistema de retroinformacion sobre la experiencia derivada de sucesos ocurridos en establecimientos nucleares. Guia de seguridad

    NONE

    2012-07-15

    This Safety Guide provides recommendations on all the main components of operating experience feedback systems, utilizing relevant information on events and abnormal conditions that have occurred at nuclear installations around the world. It focuses on the interaction between the different systems for using operating experience feedback and constitutes an update and an extension of Part I, A National System, of Systems for Reporting Unusual Events in Nuclear Power Plants (IAEA Safety Series No. 93). Contents: 1. Introduction; 2. Main elements of a national system for the feedback of operational experience; 3. Screening of events; 4. Investigation and analysis of events; 5. Corrective actions; 6. Trending and review to recognize emergent problems; 7. Utilization, dissemination and exchange of information on operating experience; 8. Reviewing the effectiveness of the process for feedback of operational experience; 9. Quality assurance; 10. Reporting of safety related events; Appendix I: Reporting criteria and categories; Appendix II: Types of event report, timing, format and content; Appendix III: Investigation and analysis of events; Appendix IV: Approval and implementation of corrective actions; Annex I: Data management for the feedback of operating experience; Annex II: Example of elements of a national feedback system for operating experience.

  8. The intensity modulated radiation therapy (IMRT) reduces rectal complications arising radiotherapy treatment of prostate cancer; La Radioterapia con modulacion de intensidad (LMRT) reduce . Las complicaciones rectales derivadas del tratamiento radioterapico del cancer prostata

    Garcia Vicente, F.; Zapatero Lobarda, A.; Rodriguez Martinez, G.; Martin de Vidales, C.; Bermudez Luna, R.; Leaman Alcibar, O.; Perez Gonzalez, L.; Cruz Conde, A.; Linan Diaz, O.; Torres Escobar, J. J.

    2013-07-01

    The objective of this analysis is to assess with adequate follow the incidence of rectal complications and know quantitatively and statistical evidence if the pattern of gastrointestinal toxicity allows us to continue with the next level of dose escalation. (Author)

  9. Synthesis and characterization of particles derived of poly(vinyl alcohol) (PVA) for treatment of embolization and chemoembolization;Sintese e caracterizacao de particulas derivadas de poli(alcool vinilico) (PVA) para embolizacao e quimioembolizacao

    Semenzim, Vinicius L.; Basso, Glaucia G.; Passos, Rodrigo A.; Nery, Jose G. [UNESP, Sao Jose do Rio Preto, SP (Brazil); Agreli, Guilherme; Oliveira, Ana P.M.L.; Kawasaki-Oyama, Rosa S.; Braile, Domingo M., E-mail: nery@ibilce.unesp.b [Braile Biomedica Industria e Comercio Representacoes S.A., Sao Jose do Rio Preto, SP (Brazil)

    2009-07-01

    The most effective way to treat cancerous tumors is by surgically removing them. However in some types of cancer, such as liver and uterine cancer, more than two-thirds of patients have no indication for surgery due to the size and location of the tumor, such as into the blood vessels. Doctors and researchers have invested in alternative and less invasive methods such as chemoembolization. The objectives of this research project are the synthesis and characterization of poly(vinyl alcohol) (PVA) particles for use in cancer treatment. PVA particles will be combined with chemotherapeutic agent Doxorubicin, drug commonly used in the treatment of cancers and carcinomas. The particles, obtained by controlled polymerization reaction followed by saponification, were characterized by SEM, XRD and NMR-CP/MAS. The functionalization of the particles with the drug is the next step of this study. (author)

  10. Alterações Geomorfológicas Derivadas Da Intervenção De Atividades Antrópicas: análise temporal na Bacia do Arroio Santa Bárbara – Pelotas (RS.

    Adriano Luís Heck Simon

    2008-11-01

    Full Text Available A análise temporal das alterações nas formas do relevo, tendo como base informações espaciais oriundas da cartografia geomorfológica, possibilita a compreensão da gênese dos distúrbios na morfodinâmica e dos impactos ambientais. Assim, este artigo foi desenvolvido com o objetivo de analisar as principais alterações geomorfológicas desencadeadas na bacia do Arroio Santa Bárbara, localizada no município de Pelotas – RS, durante 41 anos (1965 – 2006. Para avaliar as alterações ocorridas sobre a morfologia, foram elaborados mapas geomorfológicos da área em estudo, referentes aos anos de 1965 e 1995, a partir da interpretação de fotografias aéreas. O cenário de 2006 foi constituído por meio de representações cartográficas, esquematizadas a partir da obtenção de imagens orbitais do software Google Earth TM. A integralização deste mapeamento ocorreu por meio de trabalhos de campo, onde foram constatadas as transformações da morfologia e as feições geomorfológicas artificiais. As atividades antrópicas efetivaram a imposição de mecanismos de controle que alteraram as formas e a estrutura do sistema, agindo, conseqüentemente, sobre os fluxos de matéria e energia. Tais alterações vinculam-se à expansão urbana, ao desenvolvimento das atividades agrícolas e às ações antrópicas pontuais como a mineração e a interceptação dos cursos de água para a construção de reservatórios.

  11. Síntese e avaliação da atividade fitotóxica de lactonas derivadas do 2,4-dimetil-8-oxabiciclo[3.2.1]-oct-6-en-3-ona

    Barbosa Luiz Cláudio de Almeida

    2002-01-01

    Full Text Available The alkene 2,4-dimethyl-8-oxabicyclo[3.2.1]-oct-6-en-3-one (3 was converted to 1,3,10-trimethyl-8-oxabicyclo[5.3.0]-dec-3-ene-2,9-dione (7 and 1,3-dimethyl-8-oxabicyclo[5.3.0]-dec-3-ene-2,9-dione (8 with a 55% overall yield in both cases. Lactones (7 and (8 were converted in two steps to 1,3,4-trimethyl-13-methylene-6-oxatricyclo[8.3.0.0(3,7]-trideca-2,5,12-trione (12 (63% and 1,3-dimethyl-13-methylene-6-oxatricycle[8.3.0.0(3,7]-trideca-2,5,12-trione (13 (45% from 8. The effect of lactones (7, (8, (12, (13 and the intermediates (5 and (6, at the concentration of 250 mug mL-1, on the growth of Cucumis sativus L. and Sorghum bicolor L. was evaluated. The best results were observed for lactone (13 that caused 100% inhibition on the root growth of C. sativus and lactone (12 that inhibited 90% of the root growth for S. bicolor.

  12. IMPLICACIONES BIOÉTICAS DERIVADAS DEL ACCESO DE LAS PAREJAS DEL MISMO SEXO A LAS TECNOLOGÍAS PROVENIENTES DE LA BIOMEDICINA Y LA BIOTECNOLOGÍA, PARA LA CONFORMACIÓN DE FAMILIAS HOMOPARENTALES

    Zárate-Cuello, Amparo de Jesús; Celis, Luis Gustavo

    2015-01-01

    En este artículo se realiza una reflexión y una revisión, desde el ámbito de las ciencias básicas y del bioderecho, sobre los aspectos biológicos y genéticos de la homosexualidad, y sobre el impacto que tiene en la familia el acceso a las técnicas de reproducción asistida por parte de las parejas del mismo sexo. Lo anterior nos lleva al desarrollo de conceptos como la "violencia prenatal", el derecho de los niños a crecer en el seno de una familia con una imagen paterna y materna, al igual qu...

  13. Efecto del uso combinado de ácido hialurónico, plasma rico en plaquetas y células madre adultas derivadas de tejido adiposo en la reparación de defectos osteocondrales

    Cervero Suárez, Francisco Javier

    2013-01-01

    El cartílago articular es un tejido que permite la trasmisión de fuerzas y el movimiento, y para ello presenta unas características entre las que destacan la baja celularidad y la ausencia de aporte sanguíneo, de terminaciones nerviosas y de drenaje linfático. Sin embargo, estas características son a la vez una limitación crucial para la reparación de los daños. En consecuencia, se han ido desarrollando en los últimos años diferentes terapias que tratan de mejorar la baja capacidad de regene...

  14. Efecto del uso combinado de ácido hialurónico, plasma rico en plaquetas y células madre adultas derivadas de tejido adiposo en la reparación de defectos osteocondrales

    Cervero Suárez, Francisco Javier

    2016-01-01

    El cartílago articular es un tejido que permite la trasmisión de fuerzas y el movimiento, y para ello presenta unas características entre las que destacan la baja celularidad y la ausencia de aporte sanguíneo, de terminaciones nerviosas y de drenaje linfático. Sin embargo, estas características son a la vez una limitación crucial para la reparación de los daños. En consecuencia, se han ido desarrollando en los últimos años diferentes terapias que tratan de mejorar la baja capacidad de regene...

  15. La guerra de las comunidades en la ciudad de Jaén y la responsabilidad civil derivada del delito exigida por Cristóbal de Biezma y Juan de Santoyo, leales al Rey Emperador

    Luis Díaz de la Guardia y López

    2003-01-01

    Full Text Available Ya Joseph Pérez en su clásica obra sobre la Guerra de las Comunidades, en 1970, propugnaba la necesidad de investigar las consecuencias de la revuelta y, en particular, las indemnizaciones a los leales al Emperador que se exigieron tras el fin de la guerra. De esto tratan estas páginas. Concretamente de los procesos que se desencadenaron en la ciudad de Jaén para resarcir a dos de los principales acosados por los comuneros: Cristóbal de Biedma, procurador a las Cortes de La Coruña, y el letrado Juan de Santoyo. El artículo no solo analiza una documentación totalmente inédita y que se encuentra en el Archivo de la Real Chancillería de Granada, sino que da a conocer igualmente fuentes que versan sobre una de las zonas, como es la andaluza, más desconocidas por lo que respecta a este importante suceso de la Historia Moderna de la Monarquía española.As early as 1970, Joseph Pérez, in his classical work on Guerra de las Comunidades, suggested the need to do research into the consequences of the revolt, focusing on the compensations that were demanded by those who remained loyal to the Emperor This paper approaches the issue, placing special emphasis on the litigations that were triggered in the city of Jaén to compénsate two of the principal personages who were harassed by the commoners: Cristóbal de Biedma, provincial councillor for La Coruña, and the lawyer Juan de Santoyo. This article analyses documentary sources from the Archive of the Real Chancillería de Granada that were never published previously in any form. Furtliermore, it brings to light historical and documentary sources pertaining to the little known role of Andalusia during this important event in the early modern history of the Spanish monarchy.

  16. Análise nutricional e complementação alimentar de cesta básica derivada do consumo Nutritional analysis and complementation of a food basket derived of the consumption

    Sérgio A. J. Barretto

    1998-02-01

    Full Text Available INTRODUÇÃO: A "cesta básica Dieese e Procon", originada de uma Pesquisa de Padrão de Vida e Emprego no Município de São Paulo, tem sido empregada como parâmetro para o acompanhamento de preços. Seria desejável que um instrumento econômico, utilizado com esta finalidade, correspondesse também a uma nutrição efetivamente saudável. Assim, foram analisados os níveis de adequação dos itens alimentares da cesta básica em relação às necessidades nutricionais de uma família-referência paulistana, e propostas técnicas de complementação dietética para sanar possíveis deficiências ou desbalanceamento. METODOLOGIA: Utilizou-se o Censo Demográfico do IBGE, de 1991, para se determinar a família-referência; adotaram-se dois terços das "Recommended Dietary Allowances" como parâmetro de necessidades nutricionais; e utilizou-se das tabelas de composição centesimal para verificação do aporte de nutrientes da cesta básica. Efetuou-se a complementação alimentar por meio de três diferentes métodos: Ad Hoc (proposta direta e fixa, Programação Linear (proposta via computador e sazonal, com ênfase na minimização de custos, Híbrido (uma combinação dos dois anteriores. RESULTADOS: Foram encontrados valores insuficientes para as vitaminas A, C, B2 e B6 e para os minerais Ca, Mg, Fe, Zn, I e Se; o percentual de lipídios no total calórico mostrou-se elevado. Entre as técnicas de complementação, o método Híbrido pareceu assimilar, mais eficientemente, os baixos custos e os hábitos dietéticos. DISCUSSÃO: Inferiu-se uma eventual correspondência entre os problemas nutricionais detectados na relação de itens da cesta básica e a chamada transição alimentar que se processa nos países em desenvolvimento. Não parece aconselhável que os riscos epidemiológicos associados a essa alteração nos padrões dietéticos sejam incorporados num instrumento econômico que tenha por finalidade mensurar os preços de uma alimentação equilibrada.INTRODUCTION: The Dieese & Procon Basket (DPB is a list of basic foodstuffs, drawn up on the basis of a Standard of Living and Work Research project in S. Paulo city, Brazil. Seeing that it has been used as a standard for price variations, it is desirable that such an economic instrument as this, should also represent a truly healthy standard of nutrition. Thus, this study seeks to verify the adequacy of the food products in the DPB in relation to the nutritional needs of a typical reference family in S. Paulo city. It also proposes some techniques for dietary complementation. METHODOLOGY: A demographic census, undertaken in 1991 has been used to establish the reference family, as well as 2/3rds of RDA as corresponding to its nutritional needs, and the food composition tables of McCance & Widdowson to analyse the nutrient content of the DPB. Dietary complementation were undertaken by three different methods: Ad Hoc (direct suggestions, Linear Programming (computer software was utilized to minimize costs, and Hybrid (a combination of the first two. RESULTS: Food items in the DPB showed insufficient values for vitamins A, C, B2 and B6, and for minerals Ca, Mg, Fe, Zn, I and Se; besides, a relatively high fat content was found. The Hybrid Method of food complementation seems to present the best results, associating low cost and local dietary habits. DISCUSSION: A relation between the dietary deficiencies of the DPB and the nutritional transition in the developing countries may be infered. The epidemiological risks associated with these changes in eating patterns should not be incorporated into a reliable economic instrument.

  17. Enfermedades potenciales derivadas de factores de riesgo presentes en la industria de producción de alimentos Potencial diseases arising from occupational hazards in the food production industry

    Mónica Sánchez Aguilar

    2011-12-01

    Full Text Available La industria de la producción de alimentos presenta factores de riesgo laborales que van de los químicos hasta los psicosociales, por lo mismo los grupos de enfermedades que potencialmente se vinculan con ellos pueden ser aparentemente inocuas o poner en riesgo la vida del trabajador, lo que evidencia la necesidad de contar con una revisión extensa de la bibliografía nacional e internacional de enfermedades vinculadas a los riesgos presentes en los puestos de las áreas de producción hasta los puestos de mantenimiento de la industria de los alimentos. El propósito de esta publicación es evidenciar al lector el vínculo existente entre los factores de riesgos presentes en la industria de los alimentos y las enfermedades que estos pueden generar, y que frecuentemente son calificadas como enfermedades generales cuando en realidad son laborales, y así proporcionarle fundamentos sólidos según referencias nacionales e internacionales para un diagnóstico situacional y de salud más completo. Objetivos: Esta revisión pretende evidenciar el vínculo existente entre los factores de riesgos presentes en la industria de los alimentos y las enfermedades que pueden generarse a consecuencia de estos. Material y Método: Se han revisado hasta Diciembre de 2009 las siguientes bases de datos bibliográficas: Medline, SciELO, y PUBMED. Conclusiones: Un diagnóstico a fondo de enfermedades de presunto origen ocupacional implica el conocimiento y reconocimiento absoluto de los factores de riesgo laborales a los que se exponen los trabajadores diariamente o eventualmente, así como identificar rápidamente los efectos a la salud reales y potenciales de estos factores por parte de todos los responsables, directos e indirectos, de salud ocupacional al interior de los centros de trabajo.The industry of foods production presents occupational hazards that go from chemicals to psychosocial, because of that the groups of diseases that potentially been linked with them can be apparently harmless put in risk the life of the worker, which shows the need to have an extensive review of national and international bibliography of diseases linked with the risks presents in positions of production areas to maintenance positions of food industry. The propose of this publication is make evidence to the reader the link that exist between the risks factor presents in the food industry and the diseases that this can provoke, and frequently been qualified as general diseases when really are work related diseases, and thus provide solid foundations according national and international references for a situational diagnostic and health more complete. Objectives: This review aims to show the link between risk factors presents in food industry and the diseases that may occur as a result of them. Material and Methods: Have been revised to December 2009 the next bibliographic data bases: Medline, SciELO and PUBMED. Conclusions: A thorough diagnosis of diseases of presumptive occupational origin implies knowledge and full recognition that the workers been exposed every day or eventually, as well as quickly identify the real effect to the health and potential effect of these hazards by all those responsive for, direct and indirect, of occupational health within work centers.

  18. "Best-sellers" en economía, una lectura desde la geografía económica. Derivadas en el paisaje, el medio y la ordenación del territorio

    Manuel J. Marchena-Gómez

    2015-07-01

    Full Text Available En este artículo se utilizan las ideas de libros y manifiestos superventas editoriales y sus lecciones sobre la Geografía Económica internacional. Se hace un balance de los aportes de la denominada Nueva Geografía Económica y de su relación con los” best-sellers” en economía. Se ha tratado de poner en evidencia las novedades y recurrencias que sobre la Geografía Económica ejercen los autores de moda en Economía. Después de un método de selección atendiendo a criterios de venta electrónica y del interés mostrado por los medios de comunicación, se han elegido tres de éstos por su influencia y temática de interés para la Geografía Económica a escala global. Por fin, se han extraído conclusiones sobre el medio ambiente, el paisaje y la ordenación de territorio. En cualquier caso, existe un denominador común en la lectura de los textos: el rol creciente de las desigualdades territoriales y sociales en el mundo, la importancia de la calidad institucional en la interpretación de las mismas y en general, la necesidad de comunicación entre las ciencias sociales para comprender lo que pasa; más allá de aparatos formales sofisticados e irreales de índole economicista y considerados erróneamente objetos científicos en sí mismos.

  19. Diferenciação de células-tronco mesenquimais derivadas do tecido adiposo em cardiomiócitos Differentiation of adipose tissue-derived mesenchymal stem cells into cardiomyocytes

    Pablo Herthel Carvalho

    2013-01-01

    Full Text Available FUNDAMENTO: O potencial de renovação e proliferação dos cardiomiócitos, in vivo, é pequeno, e por isso, o músculo cardíaco apresenta limitada capacidade de repor células perdidas. Na tentativa de minimizar os danos oriundos de lesões hipóxico-isquêmicas e daquelas que acometem o sistema de condução do coração, a terapia celular com células-tronco mesenquimais (MSC vem sendo utilizada, inclusive com cardiomiócitos diferenciados a partir de MSC. OBJETIVO: O presente trabalho comparou três protocolos distintos de indução de diferenciação objetivando a sugestão de um método viável para a diferenciação de maior número de células funcionais que expressem fenótipo cardiomiogênico. MÉTODOS: Culturas de MSC obtidas de tecido adiposo de ratos jovens da linhagem Lewis transgênicos para proteína verde fluorescente (GFP foram submetidos a três diferentes meios de diferenciação cardiogênica: Planat-Bérnard, 5-azacitidina e meio Planat-Bérnard + 5-azacitidina e observadas quanto a expressão de marcadores celulares cardíacos. RESULTADOS: Nos três protolocos utilizados observou-se formação da proteína alfa-actinina sarcomérica no citoesqueleto das células submetidas à diferenciação, expressão de conexina 43 na membrana nuclear e citoplasmática e formação de gap junctions, necessárias para a propagação do impulso elétrico no miocárdio, contudo, em nenhum protocolo foi observada contração espontânea das células submetidas à diferenciação cardiogênica. CONCLUSÃO: A indução com 5-azacitidina proporcionou diferenciação celular cadiomiogênica efetiva e similar à encontrada com o meio Planat-Bénard e, por ser um protocolo mais simples, rápido e com menor custo torna-se o método de eleição.BACKGROUND: Cardiomyocytes have small potential for renovation and proliferation in vivo. Consequently, the heart muscle has limited capacity of self-renewal. Mesenchymal stem cells (MSC therapy, as well as MSC differentiated into cardiomyocytes, has been used in the attempt to minimize the effects of ischemic-hypoxic lesions and those affecting the electrical conduction system of the heart. OBJECTIVE: The present study compared three distinct protocols for induced differentiation of MSC into cardiomyocytes aimed at finding a viable method for producing a large number of functional cells expressing cardiomyogenic phenotype. METHODS: Mesenchymal stem cells were obtained from the adipose tissue of young transgenic Lewis rats expressing green fluorescent protein (GFP, and submitted to three distinct differentiation-inducing media: 1 Planat-Bérnard, 2 5-azacytidine, and 3 Planat-Bérnard + 5-azacytidine; further, these cells were identified based on the expression of cardiac cell markers. RESULTS: All three protocols detected the expression of sarcomeric-alpha-actinin protein in the exoskeleton of cells, expression of connexin-43 in the nuclear and cytoplasmic membrane, and formation of gap junctions, which are necessary for electrical impulse propagation in the myocardium. However, no spontaneous cell contraction was observed with any of the tested protocols. CONCLUSION: Induction with 5-azacytidine provided an effective cadiomyogenic cellular differentiation similar to that obtained with Planat-Bénard media. Therefore, 5-azacytidine was the method of choice for being the simplest, fastest and lowest-cost protocol for cell differentiation.

  20. Diferenciação de células-tronco mesenquimais derivadas do tecido adiposo em cardiomiócitos Differentiation of adipose tissue-derived mesenchymal stem cells into cardiomyocytes

    Pablo Herthel Carvalho

    2012-01-01

    Full Text Available FUNDAMENTO: O potencial de renovação e proliferação dos cardiomiócitos, in vivo, é pequeno, e por isso, o músculo cardíaco apresenta limitada capacidade de repor células perdidas. Na tentativa de minimizar os danos oriundos de lesões hipóxico-isquêmicas e daquelas que acometem o sistema de condução do coração, a terapia celular com células-tronco mesenquimais (MSC vem sendo utilizada, inclusive com cardiomiócitos diferenciados a partir de MSC. OBJETIVO: O presente trabalho comparou três protocolos distintos de indução de diferenciação objetivando a sugestão de um método viável para a diferenciação de maior número de células funcionais que expressem fenótipo cardiomiogênico. MÉTODOS: Culturas de MSC obtidas de tecido adiposo de ratos jovens da linhagem Lewis transgênicos para proteína verde fluorescente (GFP foram submetidos a três diferentes meios de diferenciação cardiogênica: Planat-Bérnard, 5-azacitidina e meio Planat-Bérnard + 5-azacitidina e observadas quanto a expressão de marcadores celulares cardíacos. RESULTADOS: Nos três protolocos utilizados observou-se formação da proteína alfa-actinina sarcomérica no citoesqueleto das células submetidas à diferenciação, expressão de conexina 43 na membrana nuclear e citoplasmática e formação de gap junctions, necessárias para a propagação do impulso elétrico no miocárdio, contudo, em nenhum protocolo foi observada contração espontânea das células submetidas à diferenciação cardiogênica. CONCLUSÃO: A indução com 5-azacitidina proporcionou diferenciação celular cadiomiogênica efetiva e similar à encontrada com o meio Planat-Bénard e, por ser um protocolo mais simples, rápido e com menor custo torna-se o método de eleição.BACKGROUND: Cardiomyocytes have small potential for renovation and proliferation in vivo. Consequently, the heart muscle has limited capacity of self-renewal. Mesenchymal stem cells (MSC therapy, as well as MSC differentiated into cardiomyocytes, has been used in the attempt to minimize the effects of ischemic-hypoxic lesions and those affecting the electrical conduction system of the heart. OBJECTIVE: The present study compared three distinct protocols for induced differentiation of MSC into cardiomyocytes aimed at finding a viable method for producing a large number of functional cells expressing cardiomyogenic phenotype. METHODS: Mesenchymal stem cells were obtained from the adipose tissue of young transgenic Lewis rats expressing green fluorescent protein (GFP, and submitted to three distinct differentiation-inducing media: 1 Planat-Bérnard, 2 5-azacytidine, and 3 Planat-Bérnard + 5-azacytidine; further, these cells were identified based on the expression of cardiac cell markers. RESULTS: All three protocols detected the expression of sarcomeric-alpha-actinin protein in the exoskeleton of cells, expression of connexin-43 in the nuclear and cytoplasmic membrane, and formation of gap junctions, which are necessary for electrical impulse propagation in the myocardium. However, no spontaneous cell contraction was observed with any of the tested protocols. CONCLUSION: Induction with 5-azacytidine provided an effective cadiomyogenic cellular differentiation similar to that obtained with Planat-Bénard media. Therefore, 5-azacytidine was the method of choice for being the simplest, fastest and lowest-cost protocol for cell differentiation.

  1. Melhoramento do cafeeiro: XLII. Produtividade de progênies derivadas de hibridação dos cultivares Laurina e Mundo Novo Coffee breeding: XLII. Yield of progenies from crosses of Laurina and Mundo Novo cultivars of Coffea arabica L.

    Alcides Carvalho

    1988-01-01

    Full Text Available O cultivar Laurina de Coffea arabica L. caracteriza-se pelo pequeno porte, folhas de dimensões reduzidas, frutos afilados na base, sementes pequenas e afiladas, pequeno rendimento e reduzida produção. Apresenta, no entanto, bebida de boa qualidade e baixo teor de cafeína nas sementes. Suas principais características são controladas pela ação de um par de alelos recessivos lrlr, de acentuado efeito pleiotrópico. Devido ao atual interesse do comércio por produto de baixo teor de cafeína, iniciaram-se pesquisas tendo em vista principalmente aumentar a produtividade do 'Laurina'. Para esse fim, realizaram-se numerosas hibridações de cafeeiros do 'Laurina' com os do 'Mundo Novo' (Coffea arabica e, posteriormente, retrocruzamentos com o 'Mundo Novo'. Estudaram-se as progênies F2 e retrocruzamentos com o 'Mundo Novo' (RC em Campinas, em um experimento, anotando-se as produções por oito anos consecutivos. Separaram-se algumas progênies F2 em dois grupos, antes do plantio: normais (LrLr,Lrlr e laurina (Irlr. Como testemunhas, usaram-se progênies do 'Mundo Novo' e 'Catuaí Amarelo' de C. arabica. O conjunto de plantas F2 do grupo laurina e os retrocruzamentos tiveram produção média maior do que as plantas F2 normais, porém menor do que as testemunhas. Alguns retrocruzamentos e progênies F2 apresentaram plantas com razoável produtividade, indicando que, através de retrocruzamentos com o 'Mundo Novo', podem-se obter novos tipos comerciais com as características morfológicas do 'Laurina'. Fizeram-se considerações sobre a melhor capacidade de combinação do 'Laurina' com algumas seleções do 'Mundo Novo'.The Laurina cultivars of Coffea arabica L. has a reduced plant size, small leaves, small and pointed seeds and low yield capacity. However the seeds have a good cup quality and the desirable characteristic of low caffeine content The Laurina phenotype is supposed to be controlled by a pair of recessive alleles lrlr, with pleiotropic effect. Due to the market interest for coffee with low caffeine content, selection work has been initiated some years ago in order to improve yield of the Laurina cultivars. Crosses and backcrosses (BC1 were undertaken with selected plants of the Mundo Novo cultivars of C. arabica and the best F1 plants were selfed. A yield trial was established in Campinas, State of São Paulo, Brazil, with two groups of F2 plants, normal (LrLr, Lrlr and Laurina (lrlr with BC1 plants, and 'Mundo Novo' and 'Catuaí Amarelo' as control cultivars. Results from the first eight consecutive harvests indicated that BC, and F2 laurina plants had higher yields than the normal F2 plants, however lower than that of the control cultivars. Some BC1 and F2 plants revealed high individual yield indicating that continued breeding of these progenies could result in selection of commercially acceptable Laurina progenies.

  2. Qualidade da bebida em espécies e populações derivadas de híbridos interespecíficos de Coffea Cupping quality of coffee species and interspecific hybrids

    Alcides Carvalho

    1990-01-01

    Full Text Available Avaliou-se, em dois experimentos, a qualidade da bebida das espécies Coffea canephora e C. congensis e derivados de híbridações interespecíficas [C. canephora duplicado (dp x C. arabica, C. canephora x C. eugenioides, C. arabica x C. dewevrei dp e C. racemosa x C. arabica]. Por tratar-se de análise de bebida de cafés pouco conhecidos, avaliou-se a eficiência de uma escala de 1 a 10 pontos em comparação à escala de 0 a 5 pontos utilizada para C. arabica. Foram, também, acrescentadas pelos provadores indicações relacionadas ao gosto da bebida. A escala de 6 pontos mostrou-se pouco eficaz na discriminação dos tratamentos e a de 10 pontos, utilizada alternativamente, revelou-se mais eficiente nos dois experimentos. No primeiro, verificou-se, quanto à qualidade, uma superioridade dos grupos C arabica x C. dewevrei dp e C. canephora dp x C. arabica pelas duas escalas. No segundo experimento, o grupo C. racemosa x C. arabica apresentou a maior média, apesar de não diferir, pela escala 1, dos demais grupos. Pela escala 2, superou, no entanto, os grupos C. canephora e C. congensis. Gostos incomuns foram observados nas amostras com relação à bebida. Atribuem-se à grande diversidade do material analisado e a falta de familiarização dos provadores com espécies bem diferentes de C. arabica, certas discrepâncias com relação à determinação desses defeitos nas amostras analisadas.Investigations on coffee cupping quality of the species C. canephora, C. congensis and several populations derived from interespecific crosses (C. canephora dp x C. arabica, C. canephora x C. eugenioides, C. arabica x C. dewevrei dp and C. racemosa x C. arabica were undertaken in two trials, in order to guide breeding programs using this germoplasm. Two grading systems were used for classification of the cupping quality, the normal six points scale used for C. arabica samples and a new one with 10 points, 1 for the lowest and 10 for the highest quality. Coffee liquorer experts graded the overall cupping quality and added remarks to any unpleasant taste noticed in the samples. The analysis of the data pointed out that both scales were not adequate for a complete characterization and discrimination of the individual samples. When coffee samples ware grouped according to the species involved in the crosses, the results indicated the superiority of the C. arabica x C, dewevrei dp and C. canephora dp x C. arabica groups in the first trial. In the second trial the C. racemosa x C. arabica group revealed the best average cupping quality, statistically superior to C. canephora and C. congensis. Most of the non-commercial coffees displayed unique tastes and were characterized in 13 unpleasant types. Due to the inherent diversity of the analysed material the liquorer experts had difficulty in classifying the several abnormal tastes influencing the classification of the mild standard sample. The results indicated the necessity of more accurate studies of the beverage produced by these species mainly when they participate in the breeding of Arabica coffee.

  3. Efecto del trasplante de células madre derivadas de la médula ósea en un modelo de ratón de ataxia de Friedreich

    Fernández Abascal, Jesús

    2014-01-01

    Trabajo de Fin de Máster en "Fisiología y Neurociencia"; Grupo de Terapia Celular en Neuropatologías:Departamento de Terapia Celular y Medicina Regenerativa (Centro Andaluz de Biología Molecular y Medicina Regenerativa-Sevilla. España).-- Tutor: José López-Barneo y Co-Tutor: Manuel Álvarez Dolado.

  4. Células madre y terapia celular

    Elso Manuel Cruz Cruz

    2015-03-01

    Full Text Available Una célula madre (CM o célula troncal es aquella capaz de dividirse indefinidamente y diferenciarse a distintos tipos de células especializadas, no sólo morfológica sino también funcionalmente. Las células madre pueden clasificarse atendiendo a su origen en células madre adultas (CMA y células madre embrionarias (CME. Por sus características, las CM tienen potencialidades para diversos usos en la práctica clínica. La primera es como vehículo terapéutico de genes, en el caso de enfermedades monogénicas o incluso como vehículo de terapias antitumorales o antiangiogénicas. La segunda y principal aplicación es, aprovechando su potencial de diferenciación, en la regeneración de tejidos destruidos o dañados, como terapia de reemplazo celular o medicina regenerativa. En esta área se están desarrollando trabajos de investigación donde se busca reemplazar células dañadas por otras que restituyan la función normal de los tejidos u órganos; en enfermedades como: diabetes mellitus, enfermedades cardiovasculares, enfermedad de Parkinson y enfermedades de células sanguíneas. Actualmente existen muchas investigaciones enfocadas a descubrir células progenitoras que sirvan como banco de células para usos terapéuticos. Se reporta el empleo de varias estrategias, las que incluyen: terapias celulares derivadas de células autólogas; terapias celulares derivadas de líneas celulares establecidas desde una variedad de CM que incluyen MO, cordón umbilical, CME, así como células de tejidos y órganos de animales genéticamente modificados. Las principales aplicaciones se realizan con CM de la médula ósea (MO, ya que esta es un recurso celular propio, accesible y abundante para la terapia celular. (1 En la MO existe un grupo heterogéneo de CMA; además de las hematopoyéticas (CMH están las: endoteliales, mesenquimales (CMM, de la población lateral, progenitoras adultas multipotentes, ovales y también células madre muy peque

  5. Stem-cells transplantation for myocardial regeneration Trasplante autólogo de médula ósea: propuesta basada en la evidencia, para un consenso en enfermedad cardiovascular

    Francisco Cuellar Ambrosi

    2005-04-01

    éneo que se desarrolla después de un "evento índice", el cual produce daño del tejido muscular cardíaco por la pérdida de cardiomiocitos o por la alteración de la capacidad del miocardio para generar una fuerza eficiente para la contracción ventricular. La noxa inicial puede ser de aparición súbita como en el síndrome coronario agudo o insidiosa y gradual como en la enfermedad coronaria crónica y las cardiomiopatías primarias y secundarias. Independiente del factor que genere el síndrome, se produce una serie de respuestas hemodinámicas y neurohormonales con cambios moleculares complejos, que conducen a la progresión de la disfunción ventricular y a mayor pérdida de células contráctiles funcionantes por necrosis o por apoptosis. Las estrategias terapéuticas desarrolladas para interrumpir este círculo vicioso de disfunción miocárdica y remodelación ventricular, cambian las condiciones en que se produce el trabajo miocárdico, con la consecuente mejoría de la enfermedad y de la tasa de supervivencia. Sin embargo, este enfoque terapéutico, conocido como la "aproximación Jurásica", no logra recuperar el tejido lesionado durante el proceso, lo que permite la progresión de la enfermedad hasta llegar a la falla cardíaca terminal y la muerte. Estudios experimentales y clínicos han demostrado que la implantación de células progenitoras derivadas de la médula ósea producen angiogénesis y recuperación de la función cardíaca en pacientes con cardiopatía isquémica aguda y crónica. Con esta terapia se ha demostrado mejoría significativa de la sintomatología, de la capacidad funcional, del estado funcional, del tamaño del defecto de perfusión miocárdica medido por pruebas de medicina nuclear y de la fracción de eyección al igual que disminución del volumen sistólico final del ventrículo izquierdo, sin complicaciones relacionadas con el procedimiento. En conclusión, el trasplante de células progenitoras derivadas de la médula ósea es

  6. ORF Alignment: NC_002570 [GENIUS II[Archive

    Full Text Available NC_002570 gi|15613166 >1ceo0 7 334 45 353 9e-20 ... dbj|BAB04322.1| endo-beta-1,4-glucanase (celula...se B) [Bacillus halodurans C-125] ... ref|NP_241469.1| endo-beta-1,4-glucanase (celulas...e B) ... [Bacillus halodurans C-125] pir||C83725 ... endo-beta-1,4-glucanase (celulase B) BH06

  7. Absence of genotoxic activity from milk and water boiled in microwave oven in somatic cells from Drosophila melanogaster; Ausencia da atividade genotoxica do leite e agua, fervidos com microondas, em celulas somaticas de Drosophila melanogaster

    Dias, Cristina das Dores. E-mail: crisddias@yahoo.com.br

    2003-07-01

    This paper reports an experiment for evaluation of the possible genotoxic effects of food prepared in a microwave oven, through the mutation test and somatic recombination, in wings of Drosophila melanogaster. Two crossing have been performed: a standard cross-ST and a high bioactivation cross - HB resulting in marked trans -heterozygote descendents (MH) and balanced heterozygotes (BH). The 72 hours larvas were fed with water and milk boiled both in the microwave oven and in the traditional way. The MH individual wings were analyzed, where the spots can be induced either by mutation or mitotic recombination. The experiment presented negative results related to the genotoxic effects of the water and milk boiled using the microwave oven, in MH descendents of both crossing. Therefore, under these experimental conditions, genotoxic activity were not presented by milk and water boiled in the microwave oven. However, an extensive study using different techniques is necessary to investigate the action of the food prepared in the microwave oven on the genetic material.

  8. Development and testing of the proton exchange membrane fuel cell (PEMFC) for stationary generation; Desenvolvimento e ensaios de uma celula a combustivel de polimero solido (PEMFC) para geracao estacionaria

    Ellern, Mara; Boccuzzi, Cyro Vicente [ELETROPAULO, Sao Caetano, SP (Brazil)], e-mail: mara.ellern@aes.com; Ett, Gerhard; Saiki, Gerson Yukio; Janolio, Gilberto [ELECTROCELL, Sao Paulo, SP (Brazil); Jardini, Jose Antonio [Universidade de Sao Paulo (USP), SP (Brazil)

    2004-07-01

    PEM (Proton Exchange Membrane) fuel cell uses a simple chemical reaction to combine hydrogen and oxygen into water, producing electric current in the process. It works something like reversed electrolysis: at the anode, hydrogen molecules give up electrons, forming hydrogen ions (this process is made possible by the platinum catalyst). The proton exchange membrane allows protons to flow through, but not electrons. As a result, the hydrogen ions flow directly through the proton exchange membrane to the cathode, while the electrons flow through an external circuit. As they travel to the cathode through the external circuit, the electrons produce electrical current. At the cathode, the electrons and hydrogen ions combine with oxygen to form water. In a fuel cell, hydrogen's natural tendency to oxidize and form water produces electricity and useful work. No pollution is produced and the only byproducts are water and heat. The huge advance on materials development combined with the growth demand of lower impact on environment is placing the fuel cells on the top of the most promising technologies world-wide. They are becoming in medium term feasible alternatives for energy generators up to energy plants of few MW. (author)

  9. Low power laser effects in cancer cells and fibroblasts submitted the ionizing radiation; Efeitos do laser de baixa potencia em celulas de linhagem tumoral e fibroblastos submetidos a radiacao ionizante

    Silva, Camila Ramos

    2015-07-01

    Cancer is considered a public health problem worldwide. According to Brazil's the National Cancer Institute (INCA), 576,000 new cases of cancer were estimated for 2015 in Brazil, representing the second leading cause of death. Radiotherapy may be a treatment to several of types of cancer, frequently using ionizing radiation to eradicate or prevent the proliferation of tumor cells. This treatment, however, can lead to death of non-tumor cells around in irradiated tissue. Given this, adjuvant therapies that can minimize the side effects of ionizing radiation are of extremely importance. In this context, low power laser (LPL) may be an alternative to modulate the response of healthy cells to ionizing radiation. In this study, cells of human gingival fibroblasts (FMM1) and breast cancer (MDAMB- 231) were exposed to gamma radiation at doses of 2.5 and 10 Gy. After twenty-four hours, cell were irradiated with LPL ( λ= 660 nm, 40 mW and total area of 0.04 cm²) with energy densities of 30, 60, 90, 120 and 150 J/cm². The cell viability was measured during four days, using the trypan blue technique. The influence of LPL on the cell cycle and on expression of the nuclear antigen of cellular proliferation (PCNA) was evaluated by flow cytometry. The expression of β-Galactosidase was the chosen method to assess cell senescence. Considering our adopted parameters, and focusing on the non-tumor cells, we have observed an increase in: 1) cell viability; 2) cell population in phases S and G{sub 2}/M cell cycle; 3) PCNA expression with decrease in senescence. No alterations were observed in the cell viability, with greater population in phases S and G{sub 2}/M cell cycle, while the number of senescent cells and the expression of PCNA were decreased. Therefore, we have concluded that the LPL promoted effects on both cell lineages, with increased cell viability on FMM1 cells, whether cancer cells maintained a decreased proliferation. (author)

  10. Fuel cell power plant - a proposal for analysis of the economical viability of the implantation; Usina a celula de combustivel - uma proposta para analise da viabilidade economica de sua implantacao

    Amendola, Alexandre Gomes; Rocha, Mauro Cesar da [ELETROBRAS, Rio de Janeiro, RJ (Brazil)

    2000-07-01

    The present work presents a methodology which allows a fast analyses of the economic viability of the implantation of fuel cell power plant. The paper also presents the practical application for two important concessionaires.

  11. Evaluation of cell number and DNA content in mouse embryos cultivated with uranium; Evaluacion del numero de celulas y el contenido de DNA en embriones murinos cultivados con uranio

    Kundt, Mirian S; Cabrini, Romulo L [Comision Nacional de Energia Atomica, General San Martin (Argentina). Dept. de Radiobiologia

    2000-07-01

    The evaluation of the degree of development, the number of cells and the DNA content, were used to evaluate the embryotoxicity of uranium. Embryos at a one cell stage were cultured with uranyl nitrate hexahydrate (UN) at a final concentration of uranium (U) of 26, 52 and 104 {mu}gU/ml. At 24 hs of culture, the embryos at the 2 cell stage, were put in new wells with the same concentrations of U as the previous day, until the end of the period of incubation at 72 hs. At 72 hs of culture, 87% of the original one cell embryos were at morula stage, and in those cultivated with uranium, the percentage decreased significantly to 77; 63.24 and 40.79% respectively for the different U concentrations. Those embryos that exhibited a normal morphology, were selected and fixed on slides. The number of cells per embryo was evaluated in Giemsa stained preparations. The DNA content was evaluated cytophotometrically in Feulgen stained nuclei. The number of cells decreased significantly from 20,3 {+-} 5.6 in the control to 19 {+-} 6; 14 {+-} 3 and 13.9 {+-} 5.6 for the different concentrations. All the embryos evaluated showed one easy recognizable polar body, which was used a haploid indicator (n). The content of DNA was measured in a total of 20 control embryos and 16 embryos cultivated with UN. In control embryos, 92,7% of the nuclei presented a normal ploidy from 2n to 4n, 2,9% nuclei were hypoploid and 4,4% were hyperploid. The percentage of hypoploid nuclei rose in a dose-dependent fashion to 3.45; 44.45 and 50.34% respectively for the embryos cultured at the different U concentrations. The results indicate that U is embryotoxic, that its effects are dose dependent at the concentrations used in this study and that even those embryos that show a normal morphology, can be genetically affected. We show that the model employed is extremely sensitive. It is possible to use the preimplantation embryos, as a model to test the effect of possibly mutagenic agents of the nuclear industry. (author)

  12. Union of {sup 99m} Tc-HYNIC-TOC at the somatostatin receptors in cells of pancreas cancer; Union del {sup 99m} Tc-HYNIC-TOC a los receptores de somatostatina en celulas de cancer de pancreas

    Rodriguez C, J [Facultad de Medicina, UAEM, 50000 Toluca, Estado de Mexico (Mexico); Ramirez I, M T [INCMNSZ, Vasco de Quiroga Num. 15, Tlalpan, 14000 Mexico D.F. (Mexico); Ferro F, G; Pedraza L, M [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico)

    2005-07-01

    The radiation toxic effects have been used in therapy however much 50 years. The absorbed radiation dose can be determined at cellular level using cancerous cell cultures. If the deposited In vitro radiation dose coming from similar activities of several therapeutic radiopharmaceuticals it can compare it will be possible to choose the therapeutic radiopharmaceutical that it offers better dosimetric characteristics for the patient. The objective of this original investigation was to determine the union percentage of the octreotide {sup 99m}Tc-HYNlC-TOC to the somatostatin receivers in cells of cancer pancreas as well as the internalization, externalization and cellular viability. It was used the octapeptide, (octreotide, TOC) labelled with {sup 99m}Tc by means of the HYNIC chelating agent (6-hydrazine pyridine-3-carboxylic acid) and 3 cellular lines of murine pancreas cancer (AR42J), of cancer of human pancreas (CAPAN) and of one negative cellular line for somatostatin receivers (WRL-68). The {sup 99m}Tc-HYNIC-TOC was compared against two negative proofs for somatostatin receivers: the peptide {sup 99m}Tc-UBI and the {sup 99m}TcO{sub 4}. The cellular lines were conserved in the synthetic media Dulbecco-Eagle. After 2, 4 and 24 h of exhibition to the radiation, the cells are picked up and its are determined the viability by count in a Neubauer camera using tripan blue. In the same times it was calculated the union percentage of the radiopharmaceutical to the cells and the internalization (union to the cytoplasm) and the externalization (union to membrane receivers). With those figures it was calculated the absorbed radiation dose at cellular level. Results: At 4 hours the union percentage of the {sup 99m}Tc-HYNlC-TOC to the AR42-J cells was 6.83 times greater than for the WRL-68 control cells of human papilloma, (without receivers of the somatostatin) and for the CAPAN them 4 times greater than for the same cells used as negative control, for the case of the {sup 99m}Tc-UBI and the {sup 99m}TcO{sub 4} one doesn't observe a significant difference and the percentage of viability of the AR42-J cells due by the {sup 99m}Tc-HYNlC-TOC it was 20% smaller in comparison with {sup 99m}Tc-UBI and {sup 99m}TcO{sub 4}. The internalization percentage of the AR42-J cells was of 43.28 {+-}1.62 due to the somatostatin receivers that its enter together with the radiopharmaceutical at the interior of the cell and 56.72 {+-}3.25 are together to the cellular membrane. (Author)

  13. Synthesis and ceramic processing of zirconia alumina composites for application as solid oxide fuel cell electrolytes; Sintese e processamento de compositos de zirconia-alumina para aplicacao como eletrolito em celulas a combustivel de oxido solido

    Garcia, Rafael Henrique Lazzari

    2007-07-01

    The global warmness and the necessity to obtain clean energy from alternative methods than petroleum raises the importance of developing cleaner and more efficient systems of energy generation, among then, the solid oxide fuel cell (SOFC). Cubic stabilized zirconia (CSZ) has been the most studied material as electrolyte in SOFC, due to its ionic conductivity and great stability at operation conditions. However, its low fracture toughness difficulties its application as a thin layer, what could lead to an improvement of cell efficiency. In this sense, the alumina addition in CSZ forms a composite, which can shift its mechanical properties, without compromising its electrical properties. In this work, coprecipitation synthesis route and ceramic processing of zirconia-alumina composites were studied, in order to establish optimum conditions to attain high density, homogeneous microstructure, and better mechanical properties than CSZ, without compromising ionic conductivity. For this purpose, composites containing up to 40 wt % of alumina, in a 9 mol % yttria-stabilized zirconia (9Y-CSZ) matrix were evaluated. In order to optimize the synthesis of the composites, a preliminary study of powder obtaining and processing were carried out, at compositions containing 20 wt % of alumina, in 9Y-CSZ. The ceramic powders were characterized by helium picnometry, X-ray diffraction, scanning electronic microscopy, transmission electronic microscopy, thermogravimetry, differential scanning calorimetry, granulometry by laser diffraction and gas adsorption (BET). The characterization of sinterized compacts were performed by X-ray diffraction, scanning electron microscopy, optical microscopy, density measurements, Vickers indentation and impedance spectroscopy. The obtained results show that the alumina addition, in the 9Y-CSZ matrix powders, raises the specific surface area, promotes deagglomeration of powders and elevates the oxides crystallization temperature, requiring higher energetic thermal treatments to attain high densities. In relation to the sintered products, it was confirmed the excellent homogeneity and crystallinity of microstructure provided by the chosen route, the restriction of grain growth by alumina addition, raise of hardness and fracture toughness, and higher ionic conductivity, even tough a lower bulk conductivity. These results indicate that the addition of 5 wt % alumina in CSZ matrix allows the application of this material as solid oxide fuel cell electrolytes, due to its better fracture toughness and ionic conductivity, compared to yttria-stabilized cubic zirconia ceramics. (author)

  14. Development of a computational model applied to a unitary 144 cm{sup 2} proton exchange membrane fuel cell; Desenvolvimento de um modelo numerico computacional aplicado a uma celula a combustivel unitaria de 144 CM{sup 2} tipo PEM

    Robalinho, Eric

    2009-07-01

    This work presents the development of a numerical computer model and methodology to study and design polymeric exchange membrane fuel cell - PEM. For the validation of experimental results, a sequence of routines, appropriate to fit the data obtained in the laboratory, was described. At the computational implementation it was created a new strategy of coupling two 3-dimensional models to satisfy the requirements of the comprehensive model of the fuel cell, including its various geometries and materials, as well as the various physical and chemical processes simulated. To effective assessment of the real cell analogy with numerical model, numerical studies were carried out. Comparisons with values obtained in the literature, characterization of variables through laboratory experiments and estimates from models already tested in the literature were also performed. Regarding the experimental part, a prototype of a fuel cell unit of 144 cm of geometric area was designed, produced and operated at laboratory with the purpose of validating the numerical computer model proposed, with positive results. The results of simulations for the 2D and 3D geometries proposed are presented in the form of polarization curves, highlighting the catalytic layer model based on the geometry of agglomerates. Parametric and sensitivity studies are presented to illustrate the change in performance of the fuel cell studied. The final model is robust and useful as a tool for design and optimization of PEM type fuel cells in a wide range of operating conditions. (author)

  15. Effect of {sup 60} Co gamma radiation on trehalose level of Saccharomyces boulardii cells; Efeito da radiacao gama {sup 60} Co nos niveis de trealose de celulas de Saccharomyces boulardii

    Santos, Raquel Gouvea dos; Neves, Maria Jose [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN), Belo Horizonte, MG (Brazil). Nucleo de Radiobiologia; Duarte, Rinaldo; Nicoli, Jacques R. [Minas Gerais Univ., Belo Horizonte, MG (Brazil). Dept. de Microbiologia

    1996-07-01

    The medicine Floratil used for diarrhea treatment is composed by lyophilized yeast cells of Saccharomyces boulardii. The action mechanism of this product is unknown. The efficacy of S. boulardii depends on its viability. The increase in the trehalose level in S. cerevisiae cells submitted to a previous sub-lethal level heat shock results in resistance to a lethal shock. The aim of this work was to study weather the cell trehalose level is involved also in the resistance of gamma irradiation. It was noted that the yeast cells surviving to gamma irradiation had more trehalose level than control cells. Apparently there is a positive correlation between of trehalose level and gamma irradiation resistance of S.boulardii cells. (author)

  16. Radiosensitizing effect of nitric oxide in tumor cells and experimental tumors irradiated with gamma rays and proton beams; Efecto radiosensibilizador del oxido nitrico en celulas tumorales y en tumores experimentales irradiados con radiacion gamma y con haces de protones

    Policastro, Lucia L; Duran, Hebe; Molinari, Beatriz L [Comision Nacional de Energia Atomica, General San Martin (Argentina). Dept. de Radiobiologia; Schuff, Juan A; Kreiner, Andres J; Burlon, Alejandro A; Debray, Mario E; Kesque, Jose M; Ozafran, Mabel J; Vazquez, Monica E [Comision Nacional de Energia Atomica, General San Martin (Argentina). Dept. de Fisica; Davidson, Jorge; Davidson, Miguel [Consejo Nacional de Investigaciones Cientificas y Tecnicas (CONICET), Buenos Aires (Argentina); Somacal, Hector R; Valda, Alejandro A [Universidad Nacional de General San Martin , Villa Ballester (Argentina). Escuela de Ciencia y Tecnologia

    2003-07-01

    Nitric oxide (NO) has been reported to be a radiosensitizer of mammalian cells under hypoxic conditions. In a previous study, we demonstrated an enhancement in radiation response induced by NO in mouse tumor cells under aerobic conditions, with an increasing effect as a function of malignancy. The aim of the present study was to evaluate the effect of NO in tumor cells and in experimental tumors irradiated with {gamma} rays and proton beams. Irradiations were performed with a {sup 137}Cs {gamma} source and with proton beams generated by the TANDAR accelerator. Tumor cells were treated with the NO donor DETA-NO and the sensitizer enhancement ratio (SER) was calculated using the {alpha} parameter of the survival curve fitted to the linear-quadratic model. Tumor cells irradiated with protons were radio sensitized by DETA-NO only in the more malignant cells irradiated with low LET protons (2.69{+-}0.08 keV/{mu}m). For higher LET protons there were no radiosensitizing effect. For human tumor cells pre-treated with DETA-NO and irradiated with {gamma} rays, a significantly greater effect was demonstrated in the malignant cells (MCF-7) as compared with the near normal cells (HBL-100). Moreover, a significant decrease in tumor growth was demonstrated in mice pre-treated with the NO donor spermine and irradiated with {gamma} rays and low LET protons as compared with mice irradiated without pre-treatment with the NO donor. In conclusion, we demonstrated a differential effect of NO as a radiosensitizer of malignant cells, both with {gamma} rays and low LET protons. This selectivity, coupled to the in vivo inhibition of tumor growth, is of great interest for the potential use of NO releasing agents in radiotherapy. (author)

  17. Influence of free radicals generated by gamma irradiation on the trehalose levels in Saccharomyces boulardii leaven cells; Influencia de radicais livres gerados pela irradiacao gama nos niveis de trealose em celulas da levedura Saccharomyces boulardii

    Martins, Flaviano dos Santos; Vianna, Cristina Roscoe [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN), Belo Horizonte, MG (Brazil). Lab. de Radiobiologia]|[Minas Gerais Univ, Belo Horizonte, MG (Brazil). Dept. de Microbiologia; Neves, Maria Jose [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN), Belo Horizonte, MG (Brazil). Lab. de Radiobiologia

    2002-07-01

    Lyophilized cells of yeast Saccharomyces boulardii were submit to the gamma irradiation ({sup 60} Cobalt). It was noted that the yeast cells surviving to gamma irradiation had more trehalose than control cells. The incubation of cells with H{sub 2}0{sub 2} induces the synthesis of trehalose but the exposition to CdCl{sub 2} induces the accumulation of trehalose only in low concentrations. Apparently there is a positive correlation between of trehalose level and gamma irradiation resistance of S. boulardii cells. It was not observed any correlation with the level of trehalose determined and the oxidative stress tested. (author)

  18. RELACION DE LA EXPRESION DEL RECEPTOR DE INSULINA CON LA EXPRESION DE LAS ENZIMAS GLICOGENICAS (GS1 Y GS2) Y GLUCONEOGENICAS EN LAS CELULAS DE TUBULO PROXIMAL DE RATAS NORMALES Y DIABETICAS

    GATICA GUTIERREZ, RODRIGO ORLANDO; GATICA GUTIERREZ, RODRIGO ORLANDO

    2012-01-01

    En el presente estudio se determinó los efectos sobre la expresión y localización del receptor de insulina (InsR), de glicógeno sin tasa (GS) y de las enzimas glicolíticas y gluconeogénicas en diabetes de largo plazo. Insulina es esencial para el manejo energético del cuerpo, sin embargo, su rol a nivel renal es poco conocido. Su unión al receptor de insulina provoca una cascada de señalización intracelular, que regula múltiples procesos biológicos, tales corno el metabolismo lipídico y pr...

  19. Synthesis and characterization of sulfonic acid membranes based on interpenetrating polymer networks for application in fuel cells; Sintese e caracterizacao de membranas sulfonadas baseadas em redes polimericas interpenetrantes para aplicacao em celulas a combustivel

    Blanco, Lyzed Toloza; Loureiro, Felipe A.M.; Rocco, Ana Maria [Grupo de Materiais Condutores e Energia, Escola de Quimica, Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil)], e-mail: amrocco@eq.ufrj.br; Pereira, Robson Pacheco [Instituto de Ciencias Exatas, Universidade Federal Fluminense (UFF), Volta Redonda, RJ (Brazil)

    2011-07-01

    In the present work, the synthesis and characterization of sulfonic membranes based on interpenetrating polymer networks (IPN). In order to obtain such systems, the diglycidyl ether of bisphenol A (DGEBA) was polymerized in presence of polyethyleneimine (PEI). These membranes were submitted to sulfonation reactions, originating IPN-SO{sub 3}H membranes. The characterization by FTIR evidenced the formation of a Semi-IPN structure, while sulfonation reactions resulted in systems containing -SO{sub 3}H groups covalently bonded to the chains. The membranes exhibited water retention up to 200 degree C, in a temperature range sufficient for application in PEMFC under hydration. (author)

  20. Synthesis of precursor the base of indene for polyelectrolyte an membrane production for application in fuel cell; Sintese de precursores a base de indeno para producao de polieletrolitos e membranas para uso em celula a combustivel

    Brum, F.J.B.; Laux, F.N.; Haack, M.S.; Forte, M.M.C. [Universidade Federal do Rio Grande do Sul. Escola de Engenharia, Porto Alegre, RS (Brazil)

    2010-07-01

    Monomers with vinyl bond can be polymerized via a cationic mechanism using acid catalysts. This study aimed to obtain homo and copolymers of styrene and indene via cationic mechanism and the functionalization of sulfonic groups to the production of membranes for fuel cells. Polymers and poly electrolytes were characterized by infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and gel permeation chromatography (GPC/SEC). The degree of sulfonation of the polymers was determined by titration and evaluated for these films to the degree of swelling in water, ion exchange capacity and analysis of electrochemical impedance spectroscopy. Membranes prepared with polyindene and PVA were tested in an apparatus of the fuel cell. (author)

  1. Study of a fuel cell insertion in a hybrid system for energy generation; Estudo da insercao de celula a combustivel integrada a sistema hibrido de geracao de eletricidade isolado

    Vale, Silvio Bispo do; Bezerra, Ubiratan Holanda; Pinho, Joao Tavares; Pereira, Edinaldo Jose da Silva [Universidade Federal do Para (UFPA), Belem, PA (Brazil). Programa de Pos-Graduacao em Engenharia Eletrica. Grupo de Estudo e Desenvolvimento em Alternativas Energeticas

    2004-07-01

    This paper presents a case study of a fuel cell (FC) insertion in a small hybrid system for energy generation composed by wind (10 kW), photovoltaic (3,2 kW) and diesel (20 kVA) generations, making computer simulations in order to evaluate the contribution of each one of the energy-supply systems involved. This paper intends to contribute for the establishment of parameters to measure the technical and economic viability for using such isolated hybrid systems, trying in the future several combinations of models to hybridize the energy generation in Amazon isolated villages, making easier the use of local energy resources. (author)

  2. Development and scale-up of the production process of NovoCell fuel cells; Desenvolvimento e 'scale-up' do processo de producao de celulas a combustivel NovoCell

    Azevedo, Dayse Caldas de; Souza, Adler de; Ferreira, Valdemar Stelita [NovoCell Sistemas de Energia S.A., Santa Barbara D' Oeste, SP (Brazil)

    2008-07-01

    Fuel cells present the potentiality to substitute the engines of internal combustion in vehicles and to supply energy for stationary use. This potentiality, however, not yet reflected in its introduction in the market with regular lines of production, because of its high cost and lack of criteria that demonstrate its reliability and durability. These subjects are the main goals of the programs of development of fuel cells worldwide. NovoCell is a Brazilian company whose objective is to develop and to produce hydrogen/air fuel cells for stationary generation. All the project is guided by the use of technologies/processes and materials that allow production in large scale and to a competitive cost, giving support to a continuous program of innovation and development of the product. In this work the technological solutions developed by the company are presented. (author)

  3. Thermodynamical simulation for solid oxide (SOFC) type fuel cells with ethanol direct internal reforming; Simulacao termodinamica para celulas a combustivel do tipo SOFC com reforma interna direta do etanol

    Silva, Aline Lima da; Malfatti, Celia de Fraga; Heck, Nestor Cezar [Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS (Brazil). Programa de Pos-Graduacao em Engenharia de Minas, Metalurgica e de Materiais (PPGEM)]. E-mail: als14br2000@yahoo.com.br; Mello, Celso Gustavo [Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS (Brazil). Programa de Pos-Graduacao em Engenharia Quimica (PPGEQ); Halmenschlager, Cibele Melo [Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS (Brazil). Programa de Pos-Graduacao em Engenharia de Minas, Metalurgica e de Materiais (PPGEM). Lab. de Materiais Ceramicos

    2008-07-01

    In SOFC, high operative temperature allows the direct conversion of ethanol into H{sub 2} to take place in the electrochemical cell. Direct internal reforming of ethanol, however, can produce undesirable products that diminish system efficiency and, in the case of carbon deposition over the anode, may occur the breakdown of the electrode. In this way, thermodynamic analysis is fundamental to predict the product distribution as well as the conditions favorable for carbon to precipitate inside the cell. Equilibrium determinations are performed by the Gibbs energy minimization method, using the GRG algorithm. Thermodynamic conditions for carbon deposition were analyzed, in order to establish temperature ranges and H{sub 2}O/ethanol ratios where carbon precipitation is not feasible. A mathematical relationship between Lagrange multipliers and carbon activity is presented, unveiling the carbon activity in atmosphere. The effect of the type of solid electrolyte (O{sup 2-} or H{sup +} conducting) on carbon formation is also investigated. The results of this work are in agreement with previous results reported in literature using the stoichiometric method. (author)

  4. Experimental energetic analysis of gas natural-powered fuel cell cogeneration plant; Analise energetica experimental de uma planta de co-geracao com celulas a combustivel e gas natural

    Furtado, Jose G.M.; Lopes, Francisco C.; Silva Junior, Fernando R.; Soares, Guilherme F.W.; Serra, Eduardo T. [Centro de Pesquisas de Energia Eletrica (CEPEL), Rio de Janeiro, RJ (Brazil)

    2008-07-01

    Power systems based on fuel cells have been considered for residential and commercial applications in energy Distributed Generation (DG) market as these systems can minimize their acquisition, installation and operation high costs. In this work we present an experimental analysis of a power generation system formed by a 5 kW proton exchange membrane fuel cell unit and a natural gas reformer (fuel processor) for hydrogen production, of the CEPEL's Fuel Cell Laboratory. It was determined the electrical performance of the cogeneration system in function of the design and operational power plant parameters. Additionally, it was verified the influence of the activation conditions of the fuel cell electrocatalytic system on the system performance. It also appeared that the use of hydrogen produced from the natural gas catalytic reforming provided the system operation in excellent electrothermal stability conditions resulting in increase of the energy conversion efficiency and of the economy of the cogeneration power plant. The maximum electrical efficiency achieved was around 38% and in all power range unit operated with average potential per single fuel cell higher than 0.60 V. (author)

  5. Energetic-economical analysis of a stationary for energy generation with fuel cells and natural gas reforming; Analise energetico-economica de um sistema estacionario de geracao de energia com celulas a combustivel e reforma de gas natural

    Furtado, Jose Geraldo de Melo; Silva Junior, Fernando Rodrigues; Silva, Cristiane Abrantes da; Soares, Guilherme Fleury Wanderley; Lopes, Francisco da Costa; Serra, Eduardo Torres [Centro de Pesquisas de Energia Eletrica (CEPEL), Rio de Janeiro, RJ (Brazil)]. E-mail: furtado@cepel.br; Codeceira Neto, Alcides [Companhia HidroEletrica do Sao Francisco (CHESF), Recife, PE (Brazil)

    2008-07-01

    Power systems based on fuel cells have been considered for residential and commercial applications in energy Distributed Generation (DG) market as these systems can minimize their acquisition, installation and operation high costs. In this work we present an experimental analysis of a power generation system formed by a 5 kW proton exchange membrane fuel cell unit and a natural gas reformer (fuel processor) for hydrogen production, of the CEPEL's Fuel Cell Laboratory. It was determined the electrical performance of the cogeneration system in function of the design and operational power plant parameters. Additionally, it was verified the influence of the activation conditions of the fuel cell electrocatalytic system on the system performance. It also appeared that the use of hydrogen produced from the natural gas catalytic reforming provided the system operation in excellent electrothermal stability conditions resulting in increase of the energy conversion efficiency and of the economicity of the cogeneration power plant. The maximum electrical efficiency achieved was around 38% and in all power range unit operated with average potential per single fuel cell higher than 0.60 V. (author)

  6. Performance of a solid oxide fuel cell with cathode containing a functional layer of LSM/YSZ film; Desempenho de uma celula a combustivel de oxido solido com catodo contendo uma camada funcional de filme LSM/YSZ

    Pires, Filipe Oliveira; Domingues, Rosana Z.; Brant, Marcia C.; Silva, Charles L.; Matencio, Tulio [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Dept. de Quimica]. E-mail: filipequiufmg@ufmg.br

    2008-07-01

    Performance of a SOFC may be evaluated by using the AC-Impedance and measuring power (P V x I). The objective of this study was to compare the performance of a fuel cell with LSM as a cathode and another one containing an additional functional composite film LSM/YSZ between the LSM and YSZ. Also it was studied variation in second cell resistance and power according to the temperature, hydrogen flux and operation time. For both cells platinum was used as anode. At 800 deg C was observed, in open current circuit, when the composite layer was introduced a decrease in resistance and high power. These results show an improvement of SOFC cathode performance with the introduction of composite LSM/YSZ layer. The maximum performance of the cell was achieved with 100 mL/min hydrogen flow at 800 deg C. The experiments also showed a performance improvement at 850 deg C. The cell behavior was stable during 318 hours of test. (author)

  7. Study of internalization and viability of multimodal nanoparticles for labeling of human umbilical cord mesenchymal stem cells; Estudo de internalizacao e viabilidade de nanoparticulas multimodal para marcacao de celulas-tronco mesenquimais de cordao umbilical humano

    Miyaki, Liza Aya Mabuchi [Faculdade de Enfermagem, Hospital Israelita Albert Einstein - HIAE, Sao Paulo, SP (Brazil); Sibov, Tatiana Tais; Pavon, Lorena Favaro; Mamani, Javier Bustamante; Gamarra, Lionel Fernel, E-mail: tatianats@einstein.br [Instituto do Cerebro - InCe, Hospital Israelita Albert Einstein - HIAE, Sao Paulo, SP (Brazil)

    2012-04-15

    Objective: To analyze multimodal magnetic nanoparticles-Rhodamine B in culture media for cell labeling, and to establish a study of multimodal magnetic nanoparticles-Rhodamine B detection at labeled cells evaluating they viability at concentrations of 10 {mu}g Fe/mL and 100{mu}g Fe/mL. Methods: We performed the analysis of stability of multimodal magnetic nanoparticles-Rhodamine B in different culture media; the mesenchymal stem cells labeling with multimodal magnetic nanoparticles-Rhodamine B; the intracellular detection of multimodal magnetic nanoparticles-Rhodamine B in mesenchymal stem cells, and assessment of the viability of labeled cells by kinetic proliferation. Results: The stability analysis showed that multimodal magnetic nanoparticles-Rhodamine B had good stability in cultured Dulbecco's Modified Eagle's-Low Glucose medium and RPMI 1640 medium. The mesenchymal stem cell with multimodal magnetic nanoparticles-Rhodamine B described location of intracellular nanoparticles, which were shown as blue granules co-localized in fluorescent clusters, thus characterizing magnetic and fluorescent properties of multimodal magnetic nanoparticles Rhodamine B. Conclusion: The stability of multimodal magnetic nanoparticles-Rhodamine B found in cultured Dulbecco's Modified Eagle's-Low Glucose medium and RPMI 1640 medium assured intracellular mesenchymal stem cells labeling. This cell labeling did not affect viability of labeled mesenchymal stem cells since they continued to proliferate for five days. (author)

  8. Development of electrode-membrane-electrode assemblies for proton exchange membrane fuel cells (PEMFC) by Sieve printing; Desenvolvimento de conjuntos eletrodo-membrana-eletrodo para celulas a combustivel a membrana trocadora de protons (PEMFC) por impressao a tela

    Andrade, Alexandre Bodart de

    2008-07-01

    The Sieve Printing process was studied in this work to apply the catalyst layers onto electrolytes utilized in PEMFC. Initially, 25 cm{sup 2} active area MEAs were built for comparison with others MEAs produced by the Spray technique. The two methods produced MEAs that showed current densities higher than 600 mA.cm{sup -2} at 600 mV. A scaling up study for 144 cm{sup 2} of active area MEAs was carried out. For this purpose, a new cell had to be projected for shelter the MEAs in such dimensions. The profile of the gas distribution channels was developed through the computational fluid dynamic tool 'Comsol Multiphysics'. For the design of the bipolar plates of the cell the 'Auto CAD' was used. The 144 cm{sup 2} MEAs made by Spray and by Sieve Printing methods were confronted with commercials MEAs ones of equal dimensions. These commercials MEAs presented better performance at 600 mV, however they were more costly than the solution developed in this study. The new method was showed to be adequate to fabricate low cost MEAs of different geometries and to produce any amount of MEAs for small scale stacks (up to 10 kW). (author)

  9. Simplified methodology for control cell constant calculations of the reactor cores for the space kinetics; Metodologia simplificada para calculos das constantes das celulas de controles dos nucleos de reatores para a cinetica espacial

    Santos, Rubens Souza dos [Instituto de Engenharia Nuclear (IEN), Rio de Janeiro, RJ (Brazil); Martinez, Aquilino Senra; Alvim, Antonio Carlos Marques [Universidade Federal, Rio de Janeiro, RJ (Brazil). Coordenacao dos Programas de Pos-graduacao de Engenharia. Programa de Engenharia Nuclear

    2002-07-01

    In this work is presented a methodology which focuses the distribution of neutron absorber rods in nuclear reactor power plants, for utilizing in space kinetic calculations, principally in the cluster ejection transients of control rods. A numerical model for macroscopic constant calculations based on the knowledge of the neutron flux without the control rods is proposed, as alternative to the analytical models, based on the hypothesis of the null current on the cell super boundaries. The proposed model in this work has itself showed adequate to deal with problems with strong space dependence, once that the model showed consistence in the global average built in the analytical model. (author)

  10. Stimulation of murine stem cell proliferation by circulating activities produced during the recovery of a radiation-induced hematopoietic injury. Estimulacion proliferativa de celulas madre hematopoyeticas de raton por actividades circulantes producidas durante la recuperacion de un dano hematopoyetico radioinducido

    Grande Azanedo, M.T.

    1989-02-01

    The proliferative activity of CFU-S, low in normal steady state, increases after treatment with different aggressors, i.e., radiation. This stimulation has been attributed in part to a local regulation system of stem cell proliferation, and at least in part to a humoral regulatory system. In the present work it has been investigated the role that circulating activities have in the CFU-S stimulation, by means of in vitro and in vivo incubation assays with diffusion chambers. The results show that bone marrow of mice irradiated with 5 Gy produces in vitro diffusible activities capable of stimulating the CFU-S proliferation. As well with this same dose circulating activities are also produced in vivo. In addition we have observed that these activities are only released during the periods of active hematopoietic regeneration that follow irradiation with moderate doses (1.5 and 5 Gy). In another set of experiments we saw that the stimulating activities are also detected in serum of mice irradiated with 5 Gy. These serum activities modify the proliferative state of very primitive precursors (12 d CFU-S). When the serum activities are added to long term bone marrow cultures the CFU-S are also stimulated to proliferate. Finally, we observed that the radiation-induced serum activities stimulate the proliferation of bone marrow CFU-S when injected into normal mice, suggesting that such activities are involved in the regulation of CFU-S proliferation.

  11. Synthesis of modified calcium aluminate with lanthanum manganite (LSM) for possible use in solid oxide fuel cell (SOFC); Sintese de aluminato de calcio modificado com manganita de lantanio (LSM) para possivel utilizacao em celula combustivel de oxido solido (SOFC)

    Veiga, F.C.T.; Jurado, J.; Sousa, V.C. de, E-mail: faili.cintia@gmail.com [Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS (Brazil). Escola de Engenharia. Departamento de Materiais; Cava, S.S. [Universidade Federal de Pelotas, RS (Brazil)

    2016-07-01

    The fuel cells solid oxide (SOFC) is made up of three basic elements: two electrodes, the anode and cathode and a conductive electrolyte ions. The objective of this work consists of calcium aluminate synthesis modified LSM in a 1: 1 by combustion synthesis method with a view to its use as a cathode in SOFC. The characterization of the post was carried out by the methods of XRD, TEM and EIS. After heat treatment at 1200°C/4 hours it was possible to obtain Ca0.5Sr1.5MnO4 and CaMnO2.56 phases. The material showed a semiconductor characteristics because with increasing temperature the electrical resistance value tends to decrease obtaining electrical conductivity greater than 10-6S / cm featuring an extrinsic semiconductor with an activation energy of 0.12. Therefore, with an activation energy value within the range of materials used for a SOFC cathodes. (author)

  12. Analysis and development of an ethanol compact reformer for hydrogen production for fuel cell; Analise e modelagem de reformador compacto de etanol para obtencao de hidrodenio para celula a combustivel

    Figueroa, P.R.F.; Oliveira, A.A.M. [Universidade Federal de Santa Catarina (UFSC), Florianopolis, SC (Brazil). Dept. de Engenharia Mecanica. Lab. de Combustao e Engenharia de Sistemas Termicos], e-mail: renzo@labcet.ufsc.br, e-mail: amirol@emc.ufsc.br

    2006-07-01

    The objective of this work is to analyze the ethanol steam reforming for hydrogen production in a compact and modular reforming unit designed for the generation of 1 kw of electrical power. For this, initially the thermodynamic limits for the steam reforming of ethanol are calculated in order to assess the limits in the production of hydrogen and other by-products and to select the best values of process stoichiometry, temperature and pressure for maximum hydrogen selectivity and minimum coke formation. In the following, a First and second Laws analysis is performed to analyze the equilibrium conditions of the main chemical reactions and to estimate the magnitude of the heat transfer required by the heating, evaporation, superheating and reforming of ethanol. Then, the catalytic reformer reactor is analyzed and sized, basing the analysis into the application of the equation for the conservation of mass of the chemical species and a model for the chemical kinetics. A basic reactor design is then proposed accompanied by the corresponding sizes and operating conditions. (author)

  13. Uncertainty of efficiency of a fuel cell with the establishing of suitable instrumentation for his measurement; Incerteza da eficiencia de uma celula a combustivel com o estabelecimento da instrumentacao adequada para a sua medicao

    Oliveira, Sergio Pinheiro de; Trota Filho, Jorge; Couto, Paulo Roberto Guimaraes; Rocha, Adriana da Cunha [Instituto Nacional de Metrologia Normalizacao e Qualidade Industrial (INMETRO), Duque de Caxias, RJ (Brazil)]. E-mail: spoliveira@inmetro.gov.br

    2008-07-01

    This work presents and compares the results obtained from the assessment of the uncertainty of measurement of the energetic efficiency calculations of a PEM unit fuel cell and from the total electrical power of a PEM fuel cell stack. This assessment makes use of three different methods of calculation: the Classical method and the Kragten method, both described in the ISO GUM 95 'Guide to the expression of uncertainty in measurement' and the Monte Carlo method, described in the Supplement 1 to the ISO GUM 95. Concerning the energetic efficiency, both the Classical and Kragten methods presented the same uncertainty values, 0.00029 whereas the Monte Carlo method presented a value of 0.00021. The difference between these two values (0.8 x 10{sup -5}) was greater than the {delta} criteria tolerance established in the Supplement 1 (0.5 x 10{sup -5}). This fact though, has not invalidated the results of the ISO GUM 95, as this work focused on the conservative value of the uncertainty. With respect to the uncertainty of the total electrical power of the fuel cell stack it has been observed that the main contribution for the uncertainty calculation, i.e., the higher uncertainty source (92.8%), was given by the accuracy class of the multimeter employed in the measurements. Additionally to the comparative study of the methods for the uncertainty calculations, this work establishes the correct accuracy class of a multimeter used for the measurement of the given/consumed electric potential by a fuel cell stack, aiming the cost/benefit relation of the process. (author)

  14. Optimal design of a hybrid photovoltaic and fuel cell power generation system, to supply isolated communities in the Brazilian Amazon; Dimensionamento otimo de sistemas hibridos, com geracao fotovoltaica e celula a combustivel, para atendimento a comunidades isoladas na Amazonia

    Silva, Sergio Batista da

    2010-11-15

    The lack of electricity in isolated communities in the Brazilian Amazon has become one of the greatest barrier for the development of the region. Currently, the main technologies that provide electricity to these communities are diesel generators, batteries and dry cells. These non-renewable energy sources may pose serious problems to the environment and human health and have high maintenance and operational costs. Therefore, the search for renewable energy sources, such as water and sunlight, which are highly abundant in the region, has become a great challenge. This thesis presents the studies on application of solar photovoltaic (PV) and fuel cell (FC) technologies to supply electric power in an uninterrupted manner. Outlined are the technical and cost issues of a pilot project set up in an environmentally protected area, next to Bananal island, located in the Southwestern region of the state of Tocantins. The pilot project relies on PV solar power as the primary source of energy for the production of electricity. The surplus energy is stored in the form of hydrogen produced by electrolysis of the water supplied locally, which is reconverted into electric power by fuel cells during periods when there is little or no sunlight. In this context, the aim of the study was to propose a sizing of a hybrid distributed generation system (HDGS), comprised of a PV system, FC and batteries, that optimizes implementation and operational costs, as a potential source of energy for isolated communities in the Amazon. The work was carried out with the help of simulation software HOMER (Hybrid Optimization Model for Electric Renewable) developed by National Renewable Energy Laboratory (NREL). Simulations and a comparative study were carried out of the technologies and potential configurations that meet the needs of these isolated communities. The results showed an optimal solution of HGDS PV-FC batteries with a reduction in the initial cost of the project in about 60% compared to the sizing system only. The HOMER simulated results also indicated that more than 50% of the costs of the PV-FC-battery HDGS regarded the PV system. (author)

  15. A Hull cell study of a NiW electrolyte and evaluation of its properties; Estudio en celula Hull de un bano electrolitico de NiW y evaluacion de sus propiedades

    Garcia-Urrutia, I.; Diez, J. A.; Muller, C.; Calvillo, P.

    2009-07-01

    Interest in NiW coatings has grown in recent years due to its favourable properties such as hardness, and resistance to both wear and corrosion, making it one of the actual alternatives to hard chromium coatings. In this work, we have undertaken a Hull cell study, investigating the influence of the metal concentration, temperature, pH and current density on the composition of the alloy formed and its thickness. We have also studied the most important properties of the NiW deposits, including morphology, hardness, and resistance to abrasion and corrosion. (Author) 9 refs.

  16. Development of a computational model applied to a unitary 144 CM{sup 2} proton exchange membrane fuel cell; Desenvolvimento de um modelo numerico computacional aplicado a uma celula a combustivel unitaria de 144 CM{sup 2} tipo PEM

    Robalinho, Eric

    2009-07-01

    This work presents the development of a numerical computer model and methodology to study and design polymeric exchange membrane fuel cell - PEM. For the validation of experimental results, a sequence of routines, appropriate to fit the data obtained in the laboratory, was described. At the computational implementation it was created a new strategy of coupling two 3-dimensional models to satisfy the requirements of the comprehensive model of the fuel cell, including its various geometries and materials, as well as the various physical and chemical processes simulated. To effective assessment of the real cell analogy with numerical model, numerical studies were carried out. Comparisons with values obtained in the literature, characterization of variables through laboratory experiments and estimates from models already tested in the literature were also performed. Regarding the experimental part, a prototype of a fuel cell unit of 144 cm{sup 2} of geometric area was designed, produced and operated at laboratory with the purpose of validating the numerical computer model proposed, with positive results. The results of simulations for the 2D and 3D geometries proposed are presented in the form of polarization curves, highlighting the catalytic layer model based on the geometry of agglomerates. Parametric and sensitivity studies are presented to illustrate the change in performance of the fuel cell studied. The final model is robust and useful as a tool for design and optimization of PEM type fuel cells in a wide range of operating conditions. (author)

  17. Performance evaluation of a fuel cell with NiO-YSV anode operating with natural gas; Avaliacao do desempenho de uma celula a combustivel com anodo de NiO YSZ operando com gas natural

    Nobrega, Shayenne Diniz da; Vasconcelos, Carmel Suzarte Ayres; Lima, Luiz Rogerio Pinho de Andrade [Universidade Federal da Bahia (UFBa), Salvador, BA (Brazil). Escola Politecnica. Dept. de Ciencia e Tecnologia dos Materiais]. E-mail: shayennedn@yahoo.com.br

    2008-07-01

    Fuel cell is an electrochemical device that converts the chemical energy into electric energy. The natural gas, for its proven improvement in the income of the equipment in relation to other energy ones, has been very used to feed the solid oxide fuel cell (SOFC) in the generation of electric power. Ceramics of Yttria-stabilized zirconia had been used as electrolyte and when supported with nickel oxide they act as anode in the solid oxide fuel cell, due to raised ionic conductivity that these materials present in high temperatures, while lanthanum with strontium and manganite are used as cathode. In the composition of the anode, the concentration of Ni O, acting as catalytic in the YSZ confers high electric conductivity and high electrochemical activity of the reactions, providing the internal reform in the SOFC. In this work, the solid oxide fuel cell, formed by Yttria- stabilized zirconia, nickel oxide, and lanthanum with strontium and manganite were tested in the reform had been prepared samples of electrode/electrolyte for use in SOFC of the natural gas in the presence of low water text, similar condition to the operation of the SOFC, operating in temperatures range from 700 to 800 deg C. This cell also was characterized using the impedance spectroscopy technique. These results allowed the development of components of the current versus voltage. (author)

  18. Synthesis and characterization of Pt-Sn-Ni alloys to application as catalysts for direct ethanol fuel cells; Sintese e caracterizacao de ligas de Pt-Sn-Ni para aplicacao como caztalisadores em celulas a combustivel do tipo DEFC

    Silva, E.L. da; Correa, P.S.; Oliveira, E.L. de; Takimi, A.S.; Malfatti, C.F., E-mail: celia.malfatti@ufrgs.b [Universidade Federal do Rio Grande do Sul (LAPEC/UFRGS), Porto Alegre, RS (Brazil). Programa de Pos-Graduacao em Engenharia Mecanica. Lab. de Pesquisa em Corrosao; Radtke, C. [Universidade Federal do Rio Grande do Sul (IQ/UFRGS), Porto Alegre, RS (Brazil). Inst. de Quimica

    2010-07-01

    Direct ethanol fuel cells (DEFCs) have been the focus of recent research due its application in mobile energy sources. In order to obtain the maximum efficiency from these systems, it is necessary the total ethanol oxidation, which implies in C-C bond break. Different catalysts described in literature are employed with this intent. This work consists in studying PtSnNi catalysts supported on carbon Vulcan XC72R, to application in DEFCs. Thus, it was used the impregnation/reduction method, varying the atomic proportion among Pt, Sn and Ni. The alloys were characterized by X-Ray Diffraction, Cyclic Voltammetry and Transmission Microscopy. Preliminary results show that predominant structure on the catalysts is the face centered cubic platinum and the densities currents are dependent on the platinum amount. (author)

  19. Union of {sup 99m} Tc-HYNIC-TOC at the somatostatin receptors in cells of pancreas cancer; Union del {sup 99m} Tc-HYNIC-TOC a los receptores de somatostatina en celulas de cancer de pancreas

    Rodriguez C, J. [Facultad de Medicina, UAEM, 50000 Toluca, Estado de Mexico (Mexico); Ramirez I, M.T. [INCMNSZ, Vasco de Quiroga Num. 15, Tlalpan, 14000 Mexico D.F. (Mexico); Ferro F, G.; Pedraza L, M. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico)

    2005-07-01

    The radiation toxic effects have been used in therapy however much 50 years. The absorbed radiation dose can be determined at cellular level using cancerous cell cultures. If the deposited In vitro radiation dose coming from similar activities of several therapeutic radiopharmaceuticals it can compare it will be possible to choose the therapeutic radiopharmaceutical that it offers better dosimetric characteristics for the patient. The objective of this original investigation was to determine the union percentage of the octreotide {sup 99m}Tc-HYNlC-TOC to the somatostatin receivers in cells of cancer pancreas as well as the internalization, externalization and cellular viability. It was used the octapeptide, (octreotide, TOC) labelled with {sup 99m}Tc by means of the HYNIC chelating agent (6-hydrazine pyridine-3-carboxylic acid) and 3 cellular lines of murine pancreas cancer (AR42J), of cancer of human pancreas (CAPAN) and of one negative cellular line for somatostatin receivers (WRL-68). The {sup 99m}Tc-HYNIC-TOC was compared against two negative proofs for somatostatin receivers: the peptide {sup 99m}Tc-UBI and the {sup 99m}TcO{sub 4}. The cellular lines were conserved in the synthetic media Dulbecco-Eagle. After 2, 4 and 24 h of exhibition to the radiation, the cells are picked up and its are determined the viability by count in a Neubauer camera using tripan blue. In the same times it was calculated the union percentage of the radiopharmaceutical to the cells and the internalization (union to the cytoplasm) and the externalization (union to membrane receivers). With those figures it was calculated the absorbed radiation dose at cellular level. Results: At 4 hours the union percentage of the {sup 99m}Tc-HYNlC-TOC to the AR42-J cells was 6.83 times greater than for the WRL-68 control cells of human papilloma, (without receivers of the somatostatin) and for the CAPAN them 4 times greater than for the same cells used as negative control, for the case of the {sup 99m}Tc-UBI and the {sup 99m}TcO{sub 4} one doesn't observe a significant difference and the percentage of viability of the AR42-J cells due by the {sup 99m}Tc-HYNlC-TOC it was 20% smaller in comparison with {sup 99m}Tc-UBI and {sup 99m}TcO{sub 4}. The internalization percentage of the AR42-J cells was of 43.28 {+-}1.62 due to the somatostatin receivers that its enter together with the radiopharmaceutical at the interior of the cell and 56.72 {+-}3.25 are together to the cellular membrane. (Author)

  20. Vitrification of nanotoxic waste (Ru) from the production of nano-catalysts for direct ethanol fuel cells; Vitrificacao de nano-residuos toxicos (Ru) provenientes da producao de nano-catalisadores para celulas a combustivel de etanol direto

    Silva, A.C.; Julio-Junior, O.; Mello-Castanho, S.R.H. [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2010-07-01

    Nanostructured catalysts have been developed for ethanol directly use in fuel cells, which due to the economic advantages that should have widespread use in the near future. The catalysts for these devices using nano-structured metal are based, where the toxic nature and environmental risks presented by these metals are largely enhanced by nano-dispersion. Thus, the production of nano-catalysts are potentially generating highly hazardous waste for public health and the environment. This study presents the treatment and inertization of ruthenium (Ru) nanoparticles waste containing by the vitrification technique and consequent attainment of silicate glasses for potential commercial use. Compositions were prepared containing up to about 20 wt % of nano-waste by changing the basic composition of glass soda-lime-borosilicate. After the fusion, at a temperature of 1100 deg C, the glasses were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and Infra-red in the Fourier transform (FT-IR) techniques. The chemical stability was evaluated by hydrolytic attack test. The glass containing 20 wt % of nano-residue showed a high chemical stability, similar to a usual soda-lime glass. (author)

  1. Materiais a base de oxidos com estrutura do tipo perovskite e compositos como anodos de PCES: Propriedades Funcionais e Comportamento Eletroquimico em Celulas com Eletrolitos Solidos a Base de Galatos e Silicatos

    Kolotygin, Vladislav

    This work was focused on the analysis of transport, thermomechanical and electrochemical properties of a series of perovskite-like oxide materials and composites for potential applications as anodes of intermediate-temperature solid oxide fuel cells (SOFCs) with lanthanum gallate and silicate solid electrolytes. The primary attention was centered on A(Mn,Nb)O3-delta (A = Sr, Ca) and (La,Sr)(Mn,Ti)O3-based systems, lanthanum chromite substituted with acceptor-type and variable-valence cations, and various Ni-containing cermets. Emphasis was given to phase stability of the materials, their crystal structure, microstructure of porous electrode layers and dense ceramics, electronic conductivity, Seebeck coefficient, oxygen permeability, thermal and chemical induced expansion, and anodic overpotentials of the electrodes deposited onto (La,Sr)(Ga,Mg)O3- and La10(Si,Al)6O27-based electrolyte membranes. In selected cases, roles of oxygen diffusivity, states of the transition metal cations relevant for the electronic transport, catalytically active additives and doped ceria protective interlayers introduced in the model electrochemical cells were assessed. The correlations between transport properties of the electrode materials and electrochemical behavior of porous electrodes showed that the principal factors governing anode performance include, in particular, electronic conduction of the anode compositions and cation interdiffusion between the electrodes and solid electrolytes. The latter is critically important for the silicatebased electrolyte membranes, leading to substantially worse anode properties compared to the electrochemical cells with lanthanum gallate solid electrolyte. The results made it possible to select several anode compositions exhibiting lower area-specific electrode resistivity compared to known analogues, such as (La,Sr)(Cr,Mn)O3-delta.

  2. Structural and optical properties of electrodeposited culnSe{sub 2} thin films for photovoltaic solar cells; Propiedades estructurales y opticas de laminas delgadas de CulnSe2 electrodepositadas para su aplicacion en celulas solares fotovoltaicas

    Guillen, C; Herrero, J; Galiano, F

    1990-07-01

    Optical an structural properties of electrodeposited copper indium diselenide, CulnSe2, thin films were studied for its application in photovoltaic devices. X-ray diffraction patterns showed that thin films were grown in chalcopyrite phase after suitable treatments. Values of Eg for the CulnSe2 thin films showed a dependence on the deposition potential as determined by optical measurements. (Author) 47 refs.

  3. Behavior of Electrochemically Prepared CuInSe{sub 2} as Photovoltaic Absorber in thin Film Solar Cells; Comportamiento del CuInSe{sub 2} Basado en Precursores Electrodepositados como Absorbente Fotovoltaico en Celulas Solares de Lamina Delgada

    Guillen, C; Martinez, M A; Dona, J M; Herrero, J; Gutierrez, M T [Ciemat.Madrid (Spain)

    2000-07-01

    Two different objective have been pursued in the present investigation: (1) optimization of the CuInSe{sub 2} preparation parameters from electrodeposited precursors, and (2) evaluation of their photovoltaic behavior by preparing and enhancing Mo/CuInSe{sub 2}/CdS/TCO devices. When Cu-In-Se precursors are directly electrodeposited, the applied potential fit is essential to improve the photovoltaic performance. Suitable absorbers have been also obtained by evaporing an In layer onto electrodeposited Cu-Se precursors. In this case, the substrate temperature during evaporation determines the CuInSe{sub 2} quality. Similar results have been reached by substituting typical Mo-Coated glass substrates by flexible Mo foils. Different TCO tested (ZnO and ITO) have been found equivalent as front electrical contact in the devices. Solar cell performance can be improved by annealing in air at 200 degree centigree. (Author) 46 refs.

  4. Environmental analysis of the proton exchange membrane fuel cell on the subject of life cycle assessment; Analise ambiental da celula a combustivel de membrana trocadora de protons sob o enfoque da avaliacao do ciclo de vida

    Fukurozaki, Sandra Harumi

    2006-07-01

    The energy is the fuel of growth and an essential requirement for the socioeconomic development. However, the current production model is based on fossil fuels, considered as threat to man and nature. As for, the relating to the human activities and their effects on the environment, they are handled by the implementation of a more rigid model of environmental control and the mobilization of the society in favor of technologies with less energy impact. In view of this scenario, the Proton Exchange Membrane Fuel Cell - PEMFC has been recognized as a key for the vital need of a clean and efficient energy. Considering the conventional power generation system, their advantages during usage configure its application as an ideal option for several utilities, especially in the mobile sector. Even though, the focus on several environmental evaluations in energy systems is referred back to the initial stage of it use, the employment relating to production of the system and to final destination should be considered, since these also present impacts. In the case of PEMFC, their previous and subsequent phases of use are issues related to the platinum catalysts, which indicates an environmental importance that cannot be overlooked. In this sense, the Life Cycle Assessment has been used to understand and to question the risks and opportunities that are associated to certain product, starting from a systemic concept of their relationships with the environment. It is precisely in this context that the present research intends to present its major contribution, starting from an exploratory study towards the its objectives to provide an environmental analysis of such technology linked to post stage of powder-use of the membrane electrode assembly - MEA, concerning the platinum catalysts, on the subject of Life Cycle Assessment - LCA. To attain such aim, the relationships between energy, environment and development are presented and discussed, as well as, the Fuel Cell technology and the current studies on LCA of PEMFC. Several questions raised up on this issues have contributed in the development of a method of recuperating the PEMFC catalysts and, particularly, for its subsequent environmental evaluation. Among significant results are the importance of LCA, out lined as useful tool for perceiving the weight of environmental matters concerning the platinum and its subsidy strategies relating to the development, consolidation and to the innovation of PEMFC. (author)

  5. Hydrogen production through allothermal ethanol reforming for fuel cells application: first generation prototype; Producao de hidrogenio atraves da reforma-vapor do etanol para aplicacoes em celulas a combustivel: prototipo de primeira geracao

    Marin Neto, Antonio Jose; Silva, Ennio Peres da; Camargo, Joao Carlos; Neves Junior, Newton Pimenta; Pinto, Cristiano da Silva [Universidade Estadual de Campinas (UNICAMP), Campinas, SP (Brazil). Lab. de Hidrogenio; Pinto, Cristiano da Silva [Centro Nacional de Referencia em Energia do Hidrogenio, Campinas, SP (Brazil)

    2004-07-01

    This paper describes preliminary results obtained with the allothermal ethanol reforming system for synthesis gas (syn-gas) production and hydrogen upgrading and purification for fuel cell applications. The system was designed to supply hydrogen to a 500 W PEM (Proton Exchange Membrane) fuel cell, with an electrical efficiency of 45%, which requires approximately 0.45 m3.h-1 of hydrogen, with a maximum carbon monoxide concentration of 20 {mu}mol.mol-1 (ppm). The study was performed changing the operation temperature and analyzing the resulting syn-gas through gas chromatography for a specific catalyst. This catalyst was tested up to 700 deg C, 1 bar and fixed stoichiometric steam to carbon ratio. The syn-gas, before carbon monoxide shift reactor implementation, was submitted to a two-bed-three-segments purification step composed of chemical and physical molecular sieves for hydrogen purification. The carbon monoxide shift reactor (water gas shift reactor) is under development to improve the efficiency-to-hydrogen and maximize the life of the purification bed. The final results also include a discussion about possible reactions involved in ethanol steam-reforming for such catalyst. (author)

  6. Performance of direct ethanol fuel cells as function of using of compressed air; Desempenho de celulas a combustivel com alimentacao direta de etanol em funcao do uso de ar comprimido

    Belchor, P.M. [UFRGS - Universidade Federal do Rio Grande do Sul, Porto Alegre, RS (Brazil); Berns, B.A.; Ferreira, R.C.; Goldbach, A.; Carpenter, D. [FURB - Fundacao Universidade Regional de Blumenau, Blumenau, SC (Brazil)

    2010-07-01

    This paper compared the performance of a direct ethanol fuel cell (CCADE) cathode feeding with air replacing the pure oxygen. The results have shown that the small decreasing of the yield of the cell under both practical and experimental situations, by the use of air replacing pure oxygen, it completely acceptable as function of great diminishing of operational costs. (author)

  7. Polymers and composites synthesis and characterization for application on PEM type fuel cells; Sintese e caracterizacao de polimeros e compositos para aplicacao em celulas a combustivel do tipo PEM

    Fiuza, Raigenis da Paz; Souza, Daniele Ribeiro; Barreto, Ednardo Gomes; Boaventura Filho, Jaime Soares; Jose, Nadia Mamede [Universidade Federal da Bahia (UFBA), Salvador, BA (Brazil)]. E-mail: raigenis@gmail.com

    2006-07-01

    The PEM (proton exchanging membrane) type fuel cell presents good potential for the energy production without the residue generation. However, its manufacture presents high costs for commercial application, mainly due to the electrolyte. Sulfonated Peek (polish-ether-ether-ketone) supported or auto immobilized the in a silicone matrix is an interesting alternative as electrolyte for PEM fuel cells. The commercial PEEK in powder form was functionalized with sulfuric acid, giving the SPEEK (Sulfonated PEEK). The membranes were produced by hot pressing the SPEEK immobilized in a silicone matrix produced by the sol-gel process. The membranes obtained were characterized by DRX, FTIR, TGA, MEV, DSC and protonic conductivity measurements. (author)

  8. Evaluation of the recombination in somatic cells induced by radiation in different stages of Drosophila larval development; Evaluacion de la recombinacion en celulas somaticas inducida por radiacion en diferentes etapas del desarrollo larvario de Drosophila

    Cruces, M P; Morales R, P [Instituto nacional de Investigaciones Nucleares, A.P. 18-1027, 11801 Mexico D.F. (Mexico)

    1997-07-01

    The mitotic recombination can happen spontaneously and its frequency is very low, however the recombination rate of a cell can be increased by the exposure to agents which cause damage to DNA. This type of agents are knew commonly as recombinogens. The ionizing radiation and a numerous chemical agents can be mentioned (Vogel, 1992). The objective of this work is to determine if the mutation/recombination rate induced by gamma rays varies with the development stage. In order to realize this investigation it was used the mutation and somatic recombination test of Drosophila wing (Graf and col. 1984). The mwh/ mwh and flr{sup 3}/TM3, Ser stocks were used. (Author)

  9. Optimization by simulation and development of solar cells with aluminium paste rear emitter and diffusion in conveyor furnace; Otimizacao por simulacao e desenvolvimento de celulas solares com emissor posterior formado por pasta de aluminio e difusao em forno de esteira

    Mallmann, Ana Paula

    2011-01-15

    Photovoltaic solar energy is the direct conversion of solar energy into electricity and it has low impact to the environment during electric energy production. The main device of this technology is the solar cell and silicon is the substrate most used. The solar cells are electrically connected and encapsulated in order to form the photovoltaic module. The aims of this thesis are to optimize, develop and to analyse n{sup +}np{sup +} solar cells processed in n type Si-PV-FZ and with aluminum rear emitter formed in belt furnace. The optimization of solar cells by simulation is an important step before the device development. The software PC-1D and another program developed using Visual Basic language were used. Considering a metal grid formed by evaporation technique in vacuum ambient an efficiency of 16.8 % may be achieved. With screen printed grid, 15.8 % efficient solar cells were obtained. From the simulation results it was found that the screen printing metallization may become more viable than evaporation technique because there is low difference in the efficiency and the screen printing is a simpler technique. The experimental optimization of silicon wafers texture process resulted in reflectance of 12 %. This value is typical for monocrystalline silicon with textured surface. Experimental optimization of phosphorus front surface field shows a sheet resistance of (36 {+-} 4) {omega}/ for this region. This region was formed in a thermal step in a conventional furnace with POCl{sub 3}. It was found that after the phosphorus diffusion occurred gettering to specific temperature and time. It was verified that the minority carrier lifetime in the final of processing is similar to the initial value. The influence of steps sequence of front silver paste firing and rear diffusion/firing aluminium paste, of surface passivation and the influence of dry air flow during the aluminium paste diffusion/firing, of aluminium paste diffusion/firing temperature and of belt speed under the fabricated devices electric characteristics were analysed. The aluminum rear emitter n{sup +}np{sup +} silicon solar cells resulted in 29 efficiency up to 9,5 %. The best solar cells were processed under 900 deg C to aluminium paste diffusion/firing and belt speed of 140 cm/min. The efficiency is limited by low values of V{sub OC} and FF reached. It was also verified that the local rear emitter formation results in solar cells with higher efficiency than those with homogeneous emitter. (author)

  10. Preparation of gas diffusion layers for PEMFC fuel cells using carbon fibers; Elaboracao de uma camada de difusao de gas a partir de fibras de carbono para aplicacao em celulas combustiveis do tipo PEMFC

    Santos, J.N.; Kunsti, S.R.; Malfatti, C.F. [Universidade Federal do Rio Grande do Sul - Departamento de Metalurgia (PPGEM) - Laboratorio de Pesquisa em Corrosao (LAPEC), Porto Alegre, RS (Brazil); Vargas, J.V.C. [Universidade Federal do Parana - Departamento de Engenharia Mecanica, PR (Brazil); Amico, S.C. [Universidade Federal do Rio Grande do Sul - Departamento de Materiais, RS (Brazil)

    2010-07-01

    The electrode/membrane system, called MEA, is the fundamental unit of a PEMFC (proton exchange membrane fuel cell). Within the MEA, the gas diffusion layer (GDL) is the bridge between the flow field and the catalyst layer. One of the important elements in a GDL is the substrate, typically a carbon cloth or paper, that has to be an excellent electrical conductor and show mechanical strength along with thermal and chemical stability. In this work, GDLs were produced from a suspension containing short carbon fibers in water-based polyurethane and poly(vinyl alcohol) (PVA) resins with appropriate characteristics to be used in low temperature fuel cells. The obtained GDL was characterized regarding its wettability, electrical conductivity and morphological aspects, evaluated by SEM. (author)

  11. Action of the chlorophyllin on the genetic damage induced by gamma radiation in germinal cells of Drosophila Melanogaster; Accion de la clorofilina sobre el dano genetico inducido por radiacion gamma en celulas germinales de Drosophila Melanogaster

    Cruces, M.P.; Pimentel, A.E.; Moreno, A.; Moreno, R. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico)

    2003-07-01

    The obtained results using somatic cells, they have evidenced that the chlorophyllin (CHLN) it can act inhibiting or increasing the damage caused by different mutagens. The objective of this investigation is to evaluate the effect of the CHLN on the damage induced by gamma radiation in germinal cells of Drosophila. Two tests were used, the lost of the X chromosome and the conventional test of lethal recessive bound to the sex (LRLS); both with a system of litters. The obtained results in both essays, indicated that the CHLN doesn't reduce the damage induced by the gamma radiation in none of the cellular monitored states. (Author)

  12. Development of materials for use in solid oxid fuel cells anodes using renewable fuels in direct operation; Desenvolvimento de materiais ceramicos aplicados em anodos de celulas a combustivel de oxidos solidos para operacao direta com combustiveis renovaveis

    Lima, D.B.P.L. de [Instituto Federal do Parana (IFPR), PR (Brazil); Florio, D.Z. de; Bezerra, M.E.O., E-mail: daniela.bianchi@ifpr.edu.br [Universidade Federal do ABC (UFABC), Santo Andre, SP (Brazil)

    2016-07-01

    Fuel cells produce electrical current from the electrochemical combustion of a gas or liquid (H2, CH4, C2H5OH, CH3OH, etc.) inserted into the anode cell. An important class of fuel cells is the SOFC (Solid Oxide Cell Fuel). It has a ceramic electrolyte that transports protons (H +) or O-2 ions and operating at high temperatures (500-1000 °C) and mixed conductive electrodes (ionic and electronic) ceramics or cermets. This work aims to develop anodes for fuel cells of solid oxide (SOFC) in order to direct operations with renewable fuels and strategic for the country (such as bioethanol and biogas). In this context, it becomes important to study in relation to the ceramic materials, especially those that must be used in high temperatures. Some types of double perovskites such as Sr2MgMoO6 (or simply SMMO) have been used as anodes in SOFC. In this study were synthesized by the polymeric precursor method, analyzed and characterized different ceramic samples of families SMMO, doped with Nb, this is: Sr2 (MgMo)1-xNbxO6 with 0 ≤ x ≤ 0.2. The materials produced were characterized by various techniques such as, thermal analysis, X-ray diffraction and scanning electron microscopy, and electrical properties determined by dc and ac measurements in a wide range of temperature, frequency and partial pressure of oxygen. The results of this work will contribute to a better understanding of advanced ceramic properties with mixed driving (electronic and ionic) and contribute to the advancement of SOFC technology operating directly with renewable fuels. (author)

  13. Study of the combined action of gamma radiation and static electric fields in human cells; Estudo da acao combinada de radiacao gama e campo eletrico estatico em celulas humanas

    Moron, Michelle Mendes

    2008-07-01

    The basic principle of radiotherapy is the one of maximizing damage to the tumor, while minimizing it in neighboring health tissues. Several strategies have been worked out aiming at increasing cellular radiosensitivity, and among them is the use of exogenous fields. Our goal in this work is the study in human cells of the effect resulting from the association of irradiation with exposure to exogenous static electric fields. The T47D cell line of breast cancer cells was irradiated with gammas in the 0 - 8 Gy doses range. The corresponding survival curve provided information on the radiosensitivity of this cell line. The rate of cell deaths per Gray in the 0 - 8 Gy range exhibited a maximum at 2 Gy, which corresponds to the most efficient irradiation dose. The viability of this T47D cells exposed to both gamma radiation and 1.250 V/cm static electric field (SEF) was about 12% lower than when only irradiated. The sole exposure of the cells to SEF by 24 and 72 hours didn't induce toxicity. Immunofluorescence runs carried out in irradiated normal MRC5 cell line of human lung fibroblast, without and with exposition to a SEF, have quantified the expression of the y- H2AX histone. The amount of phosphorylated histones was approximately 40% higher after irradiation with 2 Gy plus exposure to a SEF by 1 hour, showing that the electric field negatively interfered in the repairing process of the DNA double strand breaks. The flow cytometry analysis with FACS allowed the investigation of a possible interference of radiation and SEF in the cell distributions among the cellular cycle phases. It was found that in T47D cells treated with 1 and 2 Gy by 24 hours the SEF also negatively interfered in the DNA repairing process, as evidenced by the higher accumulation of cells in the S phase. Therefore, it would be possible to conclude that static and exogenous electric fields are able of negatively interfering in the cellular repair and, presumably, in DNA repair. (author)

  14. Processing of strontium-doped lanthanum manganite suspensions for cathode production of the solid oxide fuel cell; Processamento das suspensoes de manganito de lantanio dopado com estroncio para fabricacao do catodo da celula a combustivel de oxido solido

    Chiba, R.; Vargas, R.A.; Andreoli, M.; Seo, E.S.M. [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil). Centro de Ciencia e Tecnologia de Materiais. Lab. de SOFC - Insumos e Componentes

    2008-07-01

    The ceramic material, strontium-doped lanthanum manganite (La{sub 0,85}Sr{sub 0,15}MnO{sub 3} - LSM), has been used as cathode in Solid Oxide Fuel Cells (SOFCs). The cathode attainment as component of the SOFCs has been studied for diverse routes of synthesis and thin films forming in Yttria-stabilized zirconia (ZrO{sub 2}/Y{sub 2}O{sub 3} - YSZ) electrolyte. In this work, the LSM was synthesized by the citrate technique and deposited in YSZ substrate using the forming technique wet powder spraying. Rheological studies of suspensions and chemical, physical and microstructural characterizations of LSM powders were made, aiming at the deposition for thin films formation until 50 mum. The half unit cells LSM/YSZ sintered were characterized by scanning electron microscopy, for verification of porosity and adherence. In this sense, this work is a contribution for production of porous cathode using the forming technique wet powder spraying in the SOFCs. (author)

  15. Microstructural characterization of composite cobaltite and lanthanum-based ceria for use as fuel cell cathodes; Caracterizacao microestrutural de compositos a base de cobaltita de lantanio e ceria para aplicacao como catodos de celulas a combustivel

    Rodrigues, E.R.T.; Nascimento, R.M.; Miranda, A.C. de; Lima, A.M. de, E-mail: erickssonrtr@gmail.com [Universidade Federal do Rio Grande do Norte (UFRN), RN (Brazil); Macedo, D.A. [Universidade Federal da Paraiba (UFPB), PB (brazil)

    2016-07-01

    Fuel cells are devices that convert chemical energy into electricity via redox reactions. In this work, the lanthanum cobaltite doped with strontium and iron (La{sub 0,6}Sr{sub 0,4}Co{sub 0,2}Fe{sub 0,8}O{sub 3} - LSCF) a traditional cathodes material of the fuel cell was mixed with an electrolyte material (composite) to the base ceria doped with gadolinia and a eutectic mixture of lithium carbonates and sodium (CGO-NLC). The powders of LSCF and CGO-NLC were obtained by the citrate method and mixed to obtain a composite cathode. Samples obtained by uniaxial pressure between 5 and 10 MPa were sintered at 1100°C and investigated by X-ray diffraction, scanning electron microscopy and micro hardness test. A symmetric cell cathode / electrolyte / cathode, obtained by co-pressing and co-sintering was investigated by electron microscopy. The results indicated that the composite is chemically stable up to the sintering temperature used. The hardness ranged between 51 and 227 HV. (author)

  16. In vitro study of the effects of radio frequency generated for plasma in neoplastic cells HT-29; Estudo in vitro dos efeitos da radiofrequencia gerada por plasmas em celulas neoplasicas HT-29

    Andrighetto, Daniela; Dornelles, Eduardo Bortoluzzi; Cruz, Ivana Beatrice Manica da; Lüdke, Everton, E-mail: daniela.andrighetto@hotmail.com, E-mail: dornellesedu@gmail.com, E-mail: ibmcruz@hotmail.com, E-mail: evertonludke@gmail.com [Universidade Federal de Santa Maria (UFSM), RS (BRazil)

    2014-07-01

    The goal of this study is to develop an in vitro irradiation cell system with controllable irradiation intensities of 27 MHz produced by an argon plasma column with variable amplitude modulation in the 100-700 kHz range. This paper presents and discusses a proposed experiment, with toxicity analysis (DNA Picogreen®) and cell viability (MTT assay) in the radiation-induced HT-29 cell line (colon adenocarcinoma). The data allow us to observe that cellular toxicity effects may occur with exposure to fields produced by argon plasma with intensities on the order of at least 3.2 W / cm2 and exposure times above 3.5 hours continuously. An analysis of cell populations for cell toxicity tests using the Student's t-test did not show significant changes (p <0.05) in the amount of DNA released by the action of radiofrequency, although it has been found that cell viability (MTT) is not significantly altered by long exposures to radiation induced plasma RF signals in 27 MHz (p> 0.34). Cytotoxic effects due to the destruction of cell wall by heating the samples were not detected in any of the tests.

  17. Co-sintering of CGO/NIO-CGO bilayers for solid oxide fuel cell; Co-sinterizacao de bi-camadas anodo/eletrolito para celulas a combustivel de oxido solido

    Neto, P.P.B.; Grilo, J.P.F.; Souza, G.L.; Macedo, D.A.; Paskocimas, C.A.; Nascimento, R.M., E-mail: pbritoneto@gmail.com [Universidade Federal do Rio Grande do Norte (UFRN), Natal, RN (Brazil)

    2012-07-01

    Reducing the operating temperature of solid oxide fuel cells (SOFC) for the range between 500 and 700°C is one of the challenges which more has aroused the interest of research in SOFC in recent years. In this context, the bilayer anode/electrolyte composed of a porous support based on Ni-doped ceria (anode) and a ceria doped gadolinia (CGO) electrolyte, presents itself as one of the half-cell configurations of the most interest towards the production of electricity in the operating logic of a SOFC. In this work, CGO films were successfully prepared on NiO-CGO substrates using the resources of the screen-printing technique. The bi-layers were co-sintered between 1350 and 1450 ° C for 4 h and then characterized by scanning electron microscopy and energy dispersive X-ray spectroscopy (EDS). The results showed good adhesion at the film/substrate interface and no cracks in the films. (author)

  18. Obtainment of TiO{sub 2} powders solar cells photo electrodes dye sensitized; Obtencao de pos de TiO{sub 2} para fotoeletrodos de celulas solares sensibilizados por corante

    Forbeck, Guilherme; Folgueras, Marilena V., E-mail: guilhermeforbeck@hotmail.com [Universidade do Estado de Santa Catarina (PGCE/UDESC), SC (Brazil). Programa de Pos Graduacao em Ciencia e Engenharia de Materiais; Chinelatto, Adilson L. [Universidade Estadual de Ponta Grossa (UEPG), PR (Brazil). Programa de Mestrado em Engenharia e Ciencia dos Materiais

    2012-07-01

    Titanium dioxide in its polymorphic anatase phase, presents interesting properties for solar cells photo electrodes dye sensitized such as the forbidden energy band, high refractive index and high constant dielectric. In this study, powders of nanometric titanium dioxide were produced with predominantly the anatase phase and high surface area. We used the sol-gel method, and titanium tetraisopropoxide as a precursor, which was hydrolyzed in nitric acid solution. The obtained powder was heated to 450 ° C, varying the time for each lot (0, 20 or 120 minutes). The powders were characterized by X-ray diffraction, atomic force microscopy and surface area analysis. For all lots nanosized crystallites predominated. It was observed that in the batch with 120min heating an increase rutile content. The TiO{sub 2} with 20min heating showed high surface area, greater than that of TiO{sub 2} as taken reference.

  19. Preparation of cathode materials for solid oxide solid fuel (SOFC) using gelatin; Preparacao de materiais catodicos para celulas a combustivel de oxido solido (SOFC) atraves do uso de gelatina

    Silva, R.M.; Aquino, F. de M.; Macedo, D.A. de; Sa, A.M.; Galvao, G.O., E-mail: rinaldo_mendesa@hotmail.com [Universidade Federal da Paraiba (UFPB), Joao Pessoa, PB (Brazil)

    2016-07-01

    Fuel cells are electrochemical devices that convert chemical energy into electrical energy. These devices are basically divided into interconnectors, electrolyte, anode, and cathode. Recently, studies of improvements in microstructural and morphological properties of calcium cobaltate (Ca{sub 3}Co{sub 4}O{sub 9}, C349) has been made regarding its potential use as SOFC cathode for intermediate temperature. Gelatin has proven to be effective as a polymerizing agent in the synthesis of nanocrystalline materials. This work reports the synthesis and characterization of the C349 cathode using commercial gelatin. The structural properties of the material were determined by X-ray diffraction (XRD). Morphological characterization was performed by scanning electron microscopy (SEM). The results showed the formation of the crystalline phase at 900 °C, indicating the effectiveness of the gelatin in the preparation of cathodes for SOFC. (author)

  20. Action of the chlorophyllin on the genetic damage induced by gamma radiation in germinal cells of Drosophila Melanogaster; Accion de la clorofilina sobre el dano genetico inducido por radiacion gamma en celulas germinales de Drosophila Melanogaster

    Cruces, M P; Pimentel, A E; Moreno, A; Moreno, R [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico)

    2003-07-01

    The obtained results using somatic cells, they have evidenced that the chlorophyllin (CHLN) it can act inhibiting or increasing the damage caused by different mutagens. The objective of this investigation is to evaluate the effect of the CHLN on the damage induced by gamma radiation in germinal cells of Drosophila. Two tests were used, the lost of the X chromosome and the conventional test of lethal recessive bound to the sex (LRLS); both with a system of litters. The obtained results in both essays, indicated that the CHLN doesn't reduce the damage induced by the gamma radiation in none of the cellular monitored states. (Author)

  1. Influence of photon recycling effects in the operation and design of GaAs solar cells; Influencia del reciclaje de fotones en el funcionamiento y del diseno de las celulas solares de Arsenico de Galio

    Balenzategui Manzanares, J. L.

    2005-07-01

    Photon recycling (PR) is the process by which photons internally emitted in a semiconductor can be re-absorbed by the material, giving as result new electron-hole pairs. Although this process has been receiving some international research from the Sixties, because their effects revealed as relevant in certain devices and materials (as in gallium arsenide), its influence in the operation of solar cells has been scarcely considered in the past. Thus deposited it has been demonstrated that one of its major effects is an enhancement of the radiative carrier lifetine, photon recycling is not usually taken into account in photovoltaic, neither in device modelling and simulation, nor from the perspective of taking advantage of the phenomenon to improve the efficiency of solar cells. This work describes the results of our investigations in the field of photon recycling. (Author)

  2. Preparation, characterization and evaluation of electrocatalysts supported on functionalized carbon black for polymer exchange membrane fuel cell applications; Preparacao, caracterizacao e avaliacao de eletrocatalisadores suportados em carbono funcionalizado para aplicacao em celulas a combustivel tipo PEM

    Carmo, Marcelo do

    2008-12-18

    The fuel cell technology associated with the growing exigency of low environmental impact energy became prosperous in the world energy scenery. The fuel cell is basically a device that converts directly the chemical energy of a fuel into electrical and thermal energy with a continuous operation by the constant feed of a fuel. Especially, the carbon black Vulcan XC72 is usually employed as an electro catalyst support, and some factors as an accessible and high surface area in order to get maximum particles dispersion, pore size, adequate pore distribution and the presence of functional groups in the carbon black surface are considered fundamental characteristics for an innovative materials development. However, the Vulcan XC72 still reveals insufficient conditions for these purposes. This study consists in the preparation and in the physical chemical characterization of functionalized carbon black by hydrogen peroxide and by polymeric chains with proton conduction properties, and its posterior utilization as electro catalyst support for PEMFC and DMFC application. After the carbon functionalization, an improvement in the carbon black dispersion in water media was observed, a beneficial effect for electro catalyst preparation. It was also observed, that the functional groups and the polymeric chains worked as stabilizers in the particle growing, producing much more homogeneous electrocatalysts, exhibiting smaller average particle size. Especially, in the case of polymeric chains functionalization, a decrease in the ohmic drop was observed for this system, attributed to an improvement in the proton transference. (author)

  3. Development of electrode-membrane-electrode assemblies for proton exchange membrane fuel cells (PEMFC) by Sieve printing; Desenvolvimento de conjuntos eletrodo-membrana-eletrodo para celulas a combustivel a membrana trocadora de protons (PEMFC) por impressao a tela

    Andrade, Alexandre Bodart de

    2008-07-01

    The Sieve Printing process was studied in this work to apply the catalyst layers onto electrolytes utilized in PEMFC. Initially, 25 cm{sup 2} active area MEAs were built for comparison with others MEAs produced by the Spray technique. The two methods produced MEAs that showed current densities higher than 600 mA.cm{sup -2} at 600 mV. A scaling up study for 144 cm{sup 2} of active area MEAs was carried out. For this purpose, a new cell had to be projected for shelter the MEAs in such dimensions. The profile of the gas distribution channels was developed through the computational fluid dynamic tool 'Comsol Multiphysics'. For the design of the bipolar plates of the cell the 'Auto CAD' was used. The 144 cm{sup 2} MEAs made by Spray and by Sieve Printing methods were confronted with commercials MEAs ones of equal dimensions. These commercials MEAs presented better performance at 600 mV, however they were more costly than the solution developed in this study. The new method was showed to be adequate to fabricate low cost MEAs of different geometries and to produce any amount of MEAs for small scale stacks (up to 10 kW). (author)

  4. Development of solar cells with back surface field made by aluminum paste and belt furnace diffusion; Desenvolvimento de celulas solares com campo retrodifusor formado por pasta de aluminio e difusao em forno de esteira

    Marcolino, Juliane Bernardes

    2011-01-15

    Photovoltaics is based on the direct conversion of solar energy into electricity and is a promising alternative to diversify the world's energy matrix. This work aims to develop and analyse the deposition of Al paste by screen printing and firing/diffusion in a belt furnace to produce a BSF region in monocrystalline Si wafers. The diffusion of Al into the substrate was implemented by two different processes. In the first process the diffusion/firing of the Al paste and the firing of the Ag paste was carried out in independent steps. In this case, solar cells with an average efficiency ({eta}{sub average}) of 11.5 % and a maximum of 12.0 % were produced, but with the formation Al clusters in the back surface of the devices. In the second process firing/diffusion of such pastes was done on the same step. In this case, the best results were obtained for a firing/diffusion temperature of 860 deg C and belt furnace speed (V{sub E}) of 150 cm/min and also for 890 deg C and 180 cm/min. For the former parameters, {eta}{sub average} was 12.4 % and the maximum was 12.8 %. For the later, {eta}{sub average} was 12.5 % and the maximum was 12.6 %. Considering a temperature of 900 deg C and V{sub E} of 190 cm/min, {eta}{sub average} was 12.4 %. It was observed that minority carriers diffusion lengths were smaller than the thickness of silicon wafers. Open circuit voltages were 30 mV lower than that from similar cells fabricated at NT-Solar by using high purity Al deposited by e-beam evaporation indicating that the developed process produced low quality BSF. (author)

  5. Microstructural development and characterization of lanthanum chromite-based ceramics to application in solid oxide fuel cells; Desenvolvimento microestrutural e caracterizacao de ceramicas a base de cromita de lantanio para aplicacao em celulas a combustivel de oxido solido

    Oliveira, R.N.; Furtado, J.G. de M.; Soares, C.M.; Serra, E.T. [Centro de Pesquisas de Energia Eletrica (CEPEL), Rio de Janeiro, RJ (Brazil)], e-mail: rnunes@cepel.br

    2006-07-01

    This work has for objective to investigate and to characterize the microstructural development of lanthanum chromite-based ceramics (LaCrO{sub 3}) doped with earth alkaline metals, correlating the microstructural parameters (mainly the densification level) and processing parameters with the electrothermal properties reached. Lanthanum chromite-based ceramic systems doped with earth-alkaline metals (Ca, Mg and Sr) had been produced from respective metallic nitrates by solid state reactions process. The phase compositions were evaluated by X-ray diffraction and the densification level by Archimedes method. The microstructural characterization was effected by scanning electron microscopy, energy dispersive X-ray spectroscopy and thermal analysis techniques. Electrical tests were used to evaluate the electrical conductivity of the studied ceramics. The obtained results corroborate the literature comments concerning the difficulty of lanthanum chromite-based ceramics with high densification level and evidence the great influence of the nature of the dopants on the sintering mechanism and the microstructural and electric characteristics of the produced ceramics. The best ones results, in terms of densification and electrical conductivity, had been gotten through multiple doping with calcium and strontium, and in sintering temperature conditions lower that the normally considered to pure or monodoped lanthanum chromite-based ceramics. (author)

  6. Development and scale-up of the production process of NovoCell fuel cells; Desenvolvimento e 'scale-up' do processo de producao de celulas a combustivel NovoCell

    Azevedo, Dayse Caldas de; Souza, Adler de; Ferreira, Valdemar Stelita [NovoCell Sistemas de Energia S.A., Santa Barbara D' Oeste, SP (Brazil)]. E-mail: dayse.azevedo@novocell.ind.br

    2008-07-01

    Fuel cells present the potentiality to substitute the engines of internal combustion in vehicles and to supply energy for stationary use. This potentiality, however, not yet reflected in its introduction in the market with regular lines of production, because of its high cost and lack of criteria that demonstrate its reliability and durability. These subjects are the main goals of the programs of development of fuel cells worldwide. NovoCell is a Brazilian company whose objective is to develop and to produce hydrogen/air fuel cells for stationary generation. All the project is guided by the use of technologies/processes and materials that allow production in large scale and to a competitive cost, giving support to a continuous program of innovation and development of the product. In this work the technological solutions developed by the company are presented. (author)

  7. Synthesis of yttria-doped zirconia anodes and calcium-doped ceria electrolyte to fuel cell; Sintese de anodos de zirconia dopada com itria e eletrolito de ceria dopada com calcia para celulas a combustivel

    Almeida, G.R.S de; Fagury Neto, E.; Rabelo, A.A., E-mail: grs_gustavo@hotmail.co [Universidade Federal do Para (UFPA), Maraba, PA (Brazil). Fac. de Engenharia de Materiais

    2010-07-01

    From the pursuit of lower operating temperature of fuel cells solid oxide was used polymeric precursor for the synthesis of reactive powder compositions Zr{sub 0,92}Y{sub 0,08}O{sub 2} for the anode and Ce{sub 0,88}Ca{sub 0,12}O{sub 2} for the electrolyte. The solutions were prepared using the metal in much of the composition and citric acid molar ratio of 1:3, under stirring at 60 deg C/1 h. The mixture of metallic citrates was subjected to agitation at a temperature of 80 deg C which was added ethylene glycol in the ratio 60:40 by weight citric acid / ethylene glycol, to form a resin that was pre-calcined at 300 deg C/3 h for to form the expanded resin. The powders were disaggregated in a mortar, screened and calcined at 400, 600 and 800 deg C/2 h. The powders were characterized by standard X-ray diffraction. (author)

  8. Polymeric membranes obtained from S-PEEK for application in PEM fuel cells; Caracterizacao de membranas polimericas obtidas a partir dos S-PEEK para aplicacao em celulas combustiveis do tipo PEM

    Barreto, Ednardo G.; Fiuza, Raildo A.; Catao, Ronei S.; Jose, Nadia M.; Boaventura, Jaime S. [Universidade Federal da Bahia (UFBA), Salvador, BA (Brazil). Inst. de Quimica], e-mail: ednardobarreto@yahoo.com.br, e-mail: raildofiuza@gmail.com, e-mail: roneicatao@ig.com.br, e-mail: nadia@ufba.br, e-mail: bventura@ufba.br; Pepe, Yuri [Universidade Federal da Bahia (UFBA), Salvador, BA (Brazil). Inst. de Fisica

    2007-07-01

    This work had the objective to develop and to characterize S-PEEK membranes (sulfonated poly ether ether ketone) through chemical and electrochemical analyses. Conductivity test in function of the frequency and tension had been carried through; as well as, the open circuit tension of a fuel cell using the S-PEEK as electrolyte. Additional tests included TGA (Thermogravimetric Analysis), water absorption test, DSC (Differential Scanning Calorimetry), as tools to characterize conducting, thermal and mechanical proprieties of polymeric membrane. (author)

  9. Study of a hybrid system using solid oxide fuel cells (SOFC) and gas turbine; Estudo de um sistema hibrido empregando celula de combustivel de oxido solido (SOFC) e turbina a gas

    Souza, Antonio Carlos Caetano de; Gallo, Giulliano Batelochi; Silveira, Jose Luz [UNESP, Guaratingueta, SP (Brazil). Faculdade de Engenharia. Dept. de Energia], e-mail: caetano@feg.unesp.br

    2004-07-01

    In this paper a hybrid solid oxide fuel cell (SOFC) system, applying a combined cycle using gas turbine for rational decentralized energy production is analyzed. The relative concepts about the fuel cell are presented, followed by some chemical and technical information such as the change of Gibbs free energy in isothermal fuel oxidation directly into electricity. This represents a very high fraction of the lower heating value (LHV) of a hydrocarbon fuel. In the next step a methodology for the study of SOFC and gas turbine system is developed, considering the electricity and steam production for a hospital. This methodology is applied to energetic analysis. Natural gas is considered as a fuel. A Sankey Diagram shows that the hybrid SOFC system is a good opportunity to strengthen the decentralized energy production in Brazil. It is necessary to consider that the cogeneration in this version also is a good technical alternative, demanding special methods of design, equipment selection and contractual deals associated to electricity and fuel supply. (author)

  10. Importance of gallium-67 scintigraphy in primary cutaneous B-cell lymphoma: report of two cases;Importancia da cintilografia com galio-67 no linfoma cutaneo primario de celulas B: relato de dois casos

    Attab, Cyomara Sanches, E-mail: rubinha.attab@terra.com.b [Centro Brasileiro de Medicina Nuclear (CEBRAMEN), Goiania, GO (Brazil); Moriguchi, Sonia Marta [Fundacao Pio XII, Barretos, SP (Brazil). Hospital de Cancer; Paton, Eduardo Jose Alencar [Fundacao Pio XII, Barretos, SP (Brazil). Cancer Hospital. Div. of Hemotherapy and Bone-Marrow Transplant; Alencar, Mario Henrique Leite de [Clinica de Prevencao em Cancer, Goiania, GO, (Brazil); Rocha, Euclides Timoteo da [Fundacao Pio XII, Barretos, SP (Brazil). Cancer Hospital. Dept. of Nuclear Medicine

    2010-05-15

    The authors describe two cases of cutaneous B-cell lymphoma where correct staging, treatment and follow-up could be achieved through a combination of conventional imaging studies and gallium-67 scintigraphy. (author)

  11. Treatment of transparent conductive oxides by laser processes for the development of Silicon photovoltaic cells; Tratamiento de oxidos conductores transparentes por procesos laser para el desarrollo de celulas fotovoltaicas de silicio

    Canteli Perez-Caballero, D.

    2015-07-01

    Transparent conductive oxides (TCOs) are heavily doped oxides with high transparency in the visible range of the spectrum and a very low sheet resistance, making them very attractive for applications in optoelectronic devices. TCOs are widely found in many different areas such as low emissivity windows, electric contacts in computers, televisions or portable devices, and, specially, in the photovoltaic (PV) industry. PV industry is mainly based on mono- and multicrystalline silicon, where TCOs are used as anti-reflective coatings, but the search for cheaper, alternative technologies has led to the development of thin film PV technologies, where TCOs are used as transparent contacts. With the maturation of the thin film PV industry, laser sources have become an essential tool, allowing the improvement of some industrial processes and the development of new ones. Because of the interest on a deeper understanding of the interaction processes between laser light and TCOs, the laser ablation of three of the most important TCOs has been studied in depth in the present work. (Author)

  12. Action of the chlorophyllin before genetic damage induced by gamma radiation in germinal cells of Drosophila; Accion de la clorofilina ante el dano genetico inducido por radiacion gamma en celulas germinales de Drosophila

    Moreno B, R

    2004-07-01

    The chlorophyllin (CHLN) is a porphyrin of nutritious grade and soluble in water, derived of the chlorophyll. It has been reported that this pigment is a good anti mutagen since it reduces the damage to the DNA caused by physical or chemical agents of direct or indirect action. Their anti carcinogenic action has also been demonstrated when it is administered itself during the induced post-initiation phase by aflatoxins and heterocyclic amines. However in the last decade it has been reported that it also has promoter activity against the genetic damage induced by diverse agents like the alkyl ants of direct and indirect action, the gamma radiation and some heterocyclic amines. This effect has been observed in testing systems like Salmonella, Drosophila, rainbow trout and rodents. In the mouse spermatogonia it has been reported that it reduces the damage to the DNA but with the test of lethal dominant in Drosophila increment the damage induced by gamma radiation. The present study consisted on evaluating the effect of the CHLN in the line germinal masculine of Drosophila by means of the lethal recessive test bound to the sex (LRLS) with the stump Muller 5 and a litters system. Its were pretreated wild males with CHLN and 24 h later were irradiated with 0, 10, 20 and 40 Gy of gamma radiation immediately later were crossed with virgin females of the stump Basc and at 72 h the male was transferred to a cultivation media with three new virgin females, this process repeated three times until completing 3 litters. The F1 it was crossed among itself and in the F2 it was analysed the presence or absence of lethals. The results indicated that the CHLN per se incremented the basal frequency of damage due to the pigment can act as an agent that is inserted to the ADN causing pre mutagenic leisure. Nevertheless with the groups treated with the different doses of gamma radiation the CHLN does not present any protector action, neither promoter except in the litter I of the group treated with 20 Gy where it was observed a promoter effect of genetic damage. (Author)

  13. Action of the chlorophyllin (CHLN) on the double breaking induced by gamma radiation in germinal cells of Drosophila melanogaster; Accion de la clorofilina (CHLN) sobre los dobles rompimientos inducidos por radiacion gamma en celulas germinales de Drosophila melanogaster

    Moreno M, A

    2005-07-01

    The chlorophyllin (CHLN) is a derived of the chlorophyll in the one which the atom of Mg is replaced by Cu. It has been broadly used as preservative in those foods, and in the treatment of geriatric patients. The results using different test systems have demonstrated that the CHLN reduces the DNA damage caused by different physical agents or chemical of direct action or insinuation. Another of the properties of the CHLN is it anti carcinogenic action, because it has been that inhibits the carcinogen activity of B1 (AFB1) aflatoxin and it diminishes the incidence of tumors caused for 2-amine-3-methylimidazo [4- 5f] quinoline (IQ) and it inhibits the development of colon cancer during the post-initiation phase. Recently the reports of the activity promoter of the CHLN have been increased on the genetic damage. This effect observed in Salmonella and later on in Drosophila melanogaster using, physical and chemical agents. Presently study determines the action of the CHLN before the genetic effect induced in germinal cells of Drosophila melanogaster by means of the test of the lost one of the X chromosome in ring using two protocols; the first one consisted on pretreatment with CHLN to the male ones and later on to irradiate them and in the second protocol the pretreatment with CHLN administers to the females, in both protocols its were used a litter systems. (Author)

  14. Experimental study of a PEM 15 W fuel cell; Influencia das temperaturas de operacao e umidificacao no desempenho de uma celula combustivel tipo 'PEM' de 15 W

    Heusi, Daniel S.; Steidel, Paulo S.; Matelli, Jose A. [Universidade Federal de Santa Catarina (UFSC), Florianopolis, SC (Brazil). Lab. de Combustao e Engenharia de Sistemas Termicos (LabCET); Bazzo, Edson [Universidade Federal de Santa Catarina (UFSC), Florianopolis, SC (Brazil)

    2004-07-01

    Experimental results are presented for a fuel cell type PEM of 15 W. The influence of the operating temperature, as well as the effect of the humidification temperature in the draining of the gases Hydrogen and oxygen, are considered for analysis. The tests were performed at operating temperature in the range of 30 to 70 deg C and humidification temperature form 30 to 85 deg C. For hydrogen flows fixed to be 200 ml/min and 300 ml/min, as well as for oxygen flow of 165 ml/min, the polarization curves were raised taking into account different combinations of operation and different combinations of humidification temperatures. (author)

  15. Thermal degradation products of saccharides: effect study over Escherichia coli K12S cells; Produtos de termodegradacao de sacarideos: estudo do efeito sobre celulas de Escherichia coli K12S

    Oliveira, R.L.B.C. de

    1981-12-31

    The heat sterilization of reducing sugars, in the presence of phosphates, in alkaline pH, promotes caramelization reactions, yielding a serie of degradation products. Among them, aldehyde-like compounds seem to be responsible for the decrease in viability of DNA repair-proficient E.coli cells. A positive interaction between toxic solutions and UV-radiation effects is observed in these cells. The sinergism UV-toxic solutions varies in function of post-irradiation time and is dependent on UV dose, indicating the interference of repair processes in toxicity. The effect of non-reducing sugars on cellular viability is negligible, suggesting that toxic substances generation is linked to the presence of at least a free carbonyl group in sugar structure. All tested reducing sugars, when experimental conditions remained constant, have similarly shaped inactivation kinetics and their effects are equally inhibited by catalase activity, during incubation. (author).

  16. iDESWEB: Accesibilidad: Discapacidad en la Web

    Serna Berná, Ester; Luján Mora, Sergio (coord.)

    2012-01-01

    Qué es discapacidad, tipos de discapacidad (visuales, auditivas, motrices, neurológicas o cognitivas, derivadas del envejecimiento, derivadas del entorno), barreras de la discapacidad visual (ceguera, baja visión, daltonismo), productos de apoyo (lector de pantallas, línea de braille, navegadores de voz, pantallas grandes, ampliadores de pantalla), estrategias. tipos de discapacidad (visuales, auditivas, motrices, neurológicas o cognitivas, derivadas del envejecimiento, derivadas del entorno)...

  17. Associação dos níveis de citocinas no pós-transplante de células-tronco hematopoiéticas com a Doença do Enxerto Contra o Hospedeiro aguda Association of cytokine levels with acute graft versus host disease following full match allogeneic stem cell transplantation

    Jeane E. L. Visentainer

    2005-09-01

    Full Text Available Este estudo foi realizado para investigar se os níveis séricos de sIL-2R, TNF-alfa, IFN-gama, IL-6, IL-10 e TGF-beta1 estavam associados com o desenvolvimento de DECH (Doença do Enxerto Contra o Hospedeiro aguda. Os níveis de citocinas foram seqüencialmente mensurados por Elisa em 13 pacientes que haviam sido submetidos ao transplante alogênico de células progenitoras hematopoiéticas. Os níveis de sIL-2R e IL-10 da 1ª a 15ª semanas pós-transplante foram significativamente maiores no grupo que desenvolveu DECH aguda que naquele sem a doença. Os níveis de sIL-2R aumentaram em direta correlação com a pega do enxerto e ao tempo do DECH aguda, enquanto os níveis de IL-10 aumentaram transitoriamente pós-transplante. A média da concentração de TNF-alfa nas primeiras semanas após o transplante foi maior no grupo que desenvolveu DECH aguda. Além disso, uma queda dos níveis de TGF-beta1 após a pega esteve significativamente associada à DECH aguda. Nenhuma correlação foi encontrada entre DECH aguda e as outras citocinas investigadas. Estes resultados suportam a idéia de que um balanço entre as citocinas derivadas de linfócitos T auxiliadores do tipo 1 e 2 pode ser importante no desenvolvimento e controle da DECH aguda. Embora os níveis de sIL-2R, TNF-alfa, IL-10 e TGF-beta1 tenham sido correlacionados com a DECH aguda, os níveis de sIL-2R ao tempo da pega podem prover um melhor parâmetro para a detecção precoce de DECH aguda após o transplante alogênico.This study was performed to investigate whether the serum levels of sIL-2R, TNF-alpha, IFN-gamma, IL-6, IL-10, and TGF-beta1 are associated with the development of acute GVHD. Serum cytokine levels were sequentially measured by sandwich Enzyme Linked-Immuno-Sorbent Assay (Elisa in 13 patients who had received full match allogeneic stem cell transplantation. Serum sIL-2R and IL-10 levels from the 1st to the 15th week post transplantation were significantly higher in the

  18. Emergencia de la resistencia antibiótica debida a las β-lactamasas de espectro extendido (BLEE: detección, impacto clínico y epidemiología Emergence of antimicrobial resistance to extended-spectrum β-lactamases (ESBL: detection, clinic impact and epidemiology

    SALIM< MÁTTAR

    2007-03-01

    Full Text Available RESUMEN La rápida emergencia de la resistencia antimicrobiana debida a las BLEE tiene un impacto significativo en la salud pública. En los últimos 24 años ha suscitado un gran interés el conocimiento acerca de las BLEE, esta explosión de publicaciones abarca a todos los continentes y más de 30 países, actualmente es motivo de preocupación y se considera un problema de salud pública. Las BLEE son enzimas que producen los gram negativos y confieren resistencia a las penicilinas, a todas las cefalosporinas y al aztreonam, pero no a los carbapenems ni a las cefamicinas y la mayoría son inhibidas por el acido clavulanico. En general las BLEE son derivadas de TEM-1, TEM-2 y SHV-1, difieren entre si de sus progenitoras por unos escasos aminoácidos por lo que su filogenia es cercana. Son comúnmente encontradas en E.coli, Klebsiella sp, y P.mirabilis, no obstante, existen otras BLEE que difieren filogenéticamente de TEM y SHV, como las CTX-M, las carbapenemasas tipo OXA y las metalo-β-lactamasas VIM e IMP, típicamente encontradas en especies de P. aeruginosa, Serratia sp and Enterobacter sp. La producción de BLEE en los patógenos de importancia clínica es un problema serio en los pacientes hospitalizados debido a las implicaciones clínicas, terapéuticas y económicas. Las técnicas para la detección de las BLEE van de lo simple con aspectos fenotipicos hasta las pruebas complejas moleculares de geno-detección específica. El objetivo de esta revisión es discutir el impacto clínico y epidemiológico de las BLEE más prevalentes así como las técnicas para su detección y su seguimiento nosocomial.ABSTRACT The rapid emerge of antimicrobial resistance dueto ESBL has a significant impact in public health. In the last 24 years, the study of extendedspectrumβ-lactamases (ESBL has created great interest. This has been documented by publications from all continents and more than 30 countries, and the extent of this problem is a public

  19. Therapeutic Effect of Exosomes on Ischemic Stroke in Experimental Animals

    Carvallo, P; Astudillo, P

    2016-01-01

    La posibilidad de que los exosomas funcionen como una nueva forma de comunicación intercelular para establecer y mantener circuitos cerebrales está comenzando a ser explorada. Los exosomas son liberados desde células e interactúan con otras células receptoras para mediar cambios fisiológicos. Todas las células cerebrales liberan exosomas incluyendo las celulas madre neuronales, las neuronas, astrocitos, microglia, oligodendrocitos y las celulas endoteliales. El objetivo de esta revisión es re...

  20. Life-cycle optimization model for distributed generation in buildings

    Safaei, Amir

    principal objetivo desta tese de doutoramento foi desenvolver um modelo para otimizar o desenho e operacao de sistemas de GD para o setor da construcao de edificios comerciais em Portugal, considerando os respetivos Impactes de Ciclo de Vida (IAVC) e Custos de Ciclo de Vida (CCV), de modo a satisfazer as necessidades energeticas do edificio. Tres tipos de tecnologias de cogeracao (Micro-Turbinas, Motores de combustao interna, e Celulas combustiveis de Oxido solido), e dois tipos de tecnologias de energia solar, solar termica e fotovoltaica, constituem os sistemas de GD que sao acoplados aos sistemas convencionais. Foi desenvolvido um modelo de CV, tendo em conta todos os impactes relacionados com a construcao e operacao dos sistemas de energia, bem como os processos a montante relacionados com a producao do GN. Em particular, o mix de GN consumido em Portugal em 2011 foi identificado (60% da Nigeria, 40% da Argelia) e os impactes relativos a cada uma das vias de abastecimento foram avaliados separadamente para quatro categorias de impacte ambiental: Consumo de Energia Primaria (CEP), Gases com Efeito de Estufa (GEE), acidificacao, e eutrofizacao. Devido a importancia das emissoes de GEE na formulacao de politicas, foi tambem realizada uma analise de incerteza as emissoes de GEE do GN fornecido a Portugal. Foi desenvolvido um modelo matematico, em linguagem de Programacao General Algebraic Modeling System (GAMS), que utiliza os resultados da ACV dos sistemas de energia e as suas implicacoes economicas para minimizar o CCV e IACV ao longo de um horizonte de planeamento definido pelo decisor. Foram derivadas fronteiras otimas de Pareto, representando as relacoes entre o tipo de IACV (CEP, GEE, acidificacao, eutrofizacao) e CCV decorrentes da satisfacao das necessidades energeticas do edificio. Para aumentar a robustez do modelo, dada a incerteza dos precos dos combustiveis (GN e eletricidade), foi desenvolvido um modelo de custos robusto para os sistemas de GD, que e menos

  1. Characterization of the anti tumoral activity of the thiosemicarbazones derived from N(4)-methyl-tolyl-2acetylpyridine And 2-pyridinoformamide and its metal complex: evaluation of the radiopharmaceutical potential; Caracterizacao da atividade antitumoral das tiossemicarbazonas derivadas de N(4)-metil-toluil-2-acetilpiridina e 2-piridinoformamida e seus complexos metalicos: avaliacao do potencial radiofarmaceutico

    Silva, Paulo Roberto Ornelas da

    2008-07-01

    Thiosemicarbazones have attracted great pharmacological interest because of their biological properties, such as cytotoxic activity against multiple strains of human tumors. The most studied compounds are pyridine-based because of their resemblance to pyridoxal metabolites that attach to co-enzyme B{sub 6}-dependant enzymes. This work aimed the characterization of the anti tumoral effect of N(4)-methyl-tolyl-2-acetylpyridine and 2-pyridinoformamide-derived thiosemicarbazones and the development of a radiopharmaceutical based on a thiosemicarbazone metal complex for positron emission tomography. In the first phase of this study were synthesized twenty-one thiosemicarbazones, derived from N(4)methyl-2 acetylpyridine and 2-pyridine formamide, as well as their metal complexes (Sn, Ga and Cu). Their cytotoxic potential were evaluated against brain and breast tumor cells in vitro. Our results showed all of them presented powerful cytotoxic and antiproliferative activities against glioblastoma multiform and breast adenocarcinoma at very low concentrations (nanomolar range). Morphological alterations characteristic of apoptosis, such as cell shrinkage, chromatin condensation were observed. Copper chloride was used as control and has presented IC50 at millimolar range suggesting that copper complexation with thiosemicarbazone significantly increases (more than 1 million) the anti tumoral effect of this metal. Due to the potent anti tumoral activity of N(4)-methyl-tolyl-2-acetylpyridine derived thiosemicarbazones and the excellent properties of {sup 64}Cu (T{sub 1/2} = 12.7 hours, {beta}{sup +}, {beta}{sup -}, and EC decay), at the second part for this work it was developed a new imaging agent (radiopharmaceutical) for tumor detection by positron emission tomography (PET). The radiopharmaceuticals were produced in the nuclear reactor TRIGA-IPR-R1 from CDTN, via neutron capture reaction {sup 63}Cu (n,{gamma}) {sup 64}Cu, of the copper complex N(4)-ortho-toluyl-2-acetylpyridine thiosemicarbazone (Culac). The induced specific activity was found to be 5.55 MBq /mg. After irradiation Culac samples were analyzed by the absorption of infrared spectroscopy (IR) to assess the structural integrity. The irradiated compound kept its structural integrity. The maintenance of {sup 64}Culac biological activity was also evaluated by MTT assay on RT2 (wild p53), T98 (mutant p53), MCF-7 (wild p53) and CAE cells (wild p53). The results showed that {sup 64}Culac kept its potent anti tumoral activity against all treated cells presenting IC50 values at nanomolar range. {sup 64}Culac biodistribution studies after intravenous injection in mice bearing Erlich tumor implanted in the paw, showed significant uptake in the tumor paw (tumor/skeletal muscle ratio 6.55), 240 minutes after administration. Histopathological studies have shown mild hepatotoxicity 144 hours (6 days) after intravenous administration of 308 mg/kg of Culac. However, no lethality, behavioural, or feeding changes were observed at this dose. Our results demonstrate that the complex of copper-64 N(4)-ortho-toluyl-2-acetylpyridine thiosemicarbazone ({sup 64}Culac) is a promising radiopharmaceutical for detection of solid tumors by positron emission tomography (PET). (author)

  2. Reflections on the therapeutic use of {sup 223}RaCl{sub 2} for bone metastases resulting from prostate cancer resistant to castration; Reflexiones sobre el uso terapeutico de {sup 223}RaCl{sub 2} para metastasis osea derivada de cancer de prostata resistente a la castracion

    Astudillo V, A. J.; Paredes G, L., E-mail: armando.astudillo@inin.gob.mx [ININ, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico)

    2015-10-15

    In January 2014 the Comision Federal para la Proteccion contra Riesgos Sanitarios of the Ministry of Health in Mexico, authorize the use of {sup 223}RaCl{sub 2} as the first radiopharmaceutical emitter α for therapeutic purposes in cases of bone metastases resulting from prostate cancer resistant to castration. The paper analyzes the main variables that affect the metrological traceability using activity meters to evaluate the gamma activity of {sup 223}RaCl{sub 2} in hospitals, because it has a chain of complex decay with alpha, beta and gamma emitters, so was important to verify if a gamma activity measurement for a multiple emitter is reliable to determine the total alpha absorbed dose to bone in a patient. (Author)

  3. Análise de estruturas de madeira, com e sem impregnação de resina poliuretana derivada do óleo de mamona, aplicadas em linhas de distribuição de energia elétrica

    João Paulo Motta de Godoy

    2006-01-01

    As empresas concessionárias de energia elétrica convivem com elevados custos de manutenção em suas redes de distribuição de energia elétrica; em particular um dos motivos está ligado a preço e durabilidade de cruzetas de madeira, seja na sua instalação inicial, seja na sua troca que pode ocorrer freqüentemente, havendo a necessidade de utilização de madeiras nobres em princípios as quais, além do preço, sofrem restrições ambientais em seus usos. Este trabalho visa à análise destas vigas de ma...

  4. Percepción de alimentos en el primer lustro de vida: aspectos innatos, causalidad y modificaciones derivadas de la exposición / Food perception in the first lustrum of life: innate aspects, causality and modifications derived from repeated experiencies.

    Alejandro Chacón Villalobos

    2011-12-01

    Full Text Available ResumenEste trabajo de revisión bibliográfica describe el concepto de la percepción sensorial innata de los niños y niñas hacia los alimentos, así como los procesos por medio de los cuales esta se modifica y enriquece a través de la interacción y las experiencias alimentarias durante el primer lustro de vida. Además, la importancia del marco afectivo y social en el que este proceso formativo se da. Tanto los espacios y contextos donde se consumen y se promocionan los alimentos durante la edad preescolar, el grado de disciplina impuesta, y el nivel de autodeterminación permitido a los menores tienen, en conjunto, un impacto que perdura a lo largo de toda la vida del ser humano. Por ello, la adecuada gestión de las experiencias sensoriales orientadas a generar improntas positivas en el hogar y en el aula, es de gran importancia para educadores y padres de familia por igual. La neofobia y la aversión a los alimentos, así como el rol de los medios de comunicación, son también abordadas complementariamente.AbstractThis paper review describes the innate sensorial perception of the children towards foods, as well as the processes by means of which this perception modifies and enriches through the interaction and the exposure to food during the first five years of life. It evaluates, in addition, the importance of the affective and social frame in which this formative process occurs. The spaces and contexts in which the foods are both consumed and promoted, the degree of imposed discipline, and the level of self-determination allowed to the minors, have altogether an impact that lasts throughout the entire lifespan of the human being. For this reason, a suitable management of the sensorial experiences oriented to generate positive impressions at the home and at the classroom, is of great importance for both educators and parents. Food neophobia and aversion, as well as the roll of mass media are also explained complementarily.

  5. Geometria da valva mitral derivada da ressonância magnética cardiovascular na avaliação da gravidade da regurgitação mitral Cardiovascular magnetic resonance imaging-derived mitral valve geometry in determining mitral regurgitation severity

    Andre Mauricio Fernandes

    2013-01-01

    Full Text Available FUNDAMENTO: A regurgitação mitral é a doença valvar cardíaca mais comum em todo o mundo. A ressonância magnética pode ser uma ferramenta útil para analisar os parâmetros da valva mitral. OBJETIVO: diferenciar padrões geométricos da valva mitral em pacientes com diferentes gravidades por regurgitação mitral (RM com base na ressonância magnética cardiovascular. MÉTODOS: Sessenta e três pacientes foram submetidos à ressonância magnética cardiovascular. Os parâmetros da valva mitral analisados foram: área (mm2 e ângulo (graus de tenting, altura do ventrículo (mm, altura do tenting (mm, folheto anterior, comprimento posterior do folheto (leaflet e diâmetro do anulo (mm. Os pacientes foram divididos em dois grupos, um incluindo pacientes que necessitaram de cirurgia da valva mitral e o outro os que não. RESULTADOS: Trinta e seis pacientes apresentaram de RM discreta a leve (1-2+ e 27 RM de moderada a grave (3-4+. Dez (15,9% dos 63 pacientes foram submetidos à cirurgia. Pacientes com RM mais grave tiveram maior diâmetro sistólico final do ventrículo esquerdo (38,6 ± 10,2 vs. 45,4 ± 16,8, p BACKGROUND: Mitral regurgitation is the most common valvular heart disease worldwide. Magnetic resonance may be a useful tool to analyze mitral valve parameters. OBJECTIVE: To distinguish mitral valve geometric patterns in patients with different severities of mitral regurgitation (MR based on cardiovascular magnetic resonance imaging. METHODS: Sixty-three patients underwent cardiovascular magnetic resonance imaging. Mitral valve parameters analyzed were: tenting area (mm2 and angle (degrees, ventricle height (mm, tenting height (mm, anterior leaflet, posterior leaflet length and annulus diameter (mm. Patients were divided into two groups, one including patients who required mitral valve surgery and another which did not. RESULTS: Thirty-six patients had trace to mild (1-2+ MR and 27 had moderate to severe MR (3-4+. Ten (15.9% out of 63 patients underwent surgery. Patients with more severe MR had a larger left ventricle end systolic diameter (38.6 ± 10.2 vs 45.4 ± 16.8, p<0.05 and left end diastolic diameter (52.9 ± 6.8 vs 60.1 ± 12.3, p= 0.005. On multivariate analysis, the tenting area was the strongest determinant of MR severity (r= 0.62, p=0.035. Annulus length (36.1 ± 4.7 vs 41 ± 6.7, p< 0.001, tenting area (190.7 ± 149.7 vs 130 ± 71.3, p= 0.048 and posterior leaflet length (15.1 ± 4.1 vs 12.2 ± 3.5, p= 0.023 were larger on patients requiring mitral valve surgery. CONCLUSIONS: Tenting area, annulus and posterior leaflet length are possible determinants of MR severity. These geometric parameters could be used to determine severity and could, in the future, direct specific patient care based on individual mitral apparatus anatomy.

  6. Alterações derivadas de uma mudança de instalações de parques de palha para cubículos de areia a nível comportamental, a nível da saúde e a nível produtivo, num grupo de vacas leiteiras de alta produção

    Ajuda, Inês de Grenho Gonçalves

    2012-01-01

    Dissertação de Mestrado Integrado em Medicina Veterinária A importância da mudança de instalações prende-se não só pelo facto de corresponder a um elevado investimento, mas também pelas repercussões que pode trazer para a saúde e bem-estar animal. Como tal, devem ser conhecidas e monitorizadas as alterações verificadas para que a mudança decorra o melhor possível. Este estudo decorreu numa exploração de vacas leiteiras na região de Canha com uma média de 370 animais em ordenha, onde as ...

  7. Environmental and ecological architects: Guidelines for the Chilean temperate rainforest management derived from the monito del monte (Dromiciops gliroides conservation Arquitectos ambientales y ecológicos: Pautas para la gestión ambiental del bosque templado lluvioso de Chile derivadas de la conservación del monito del monte (Dromiciops gliroides

    FRANCISCO E FONTÚRBEL

    2011-06-01

    Full Text Available Land use change is one of the main biodiversity threats. Due to this change, natural habitats such as the South American temperate rainforests have been rapidly degraded, fragmented, and lost. Consequently, the management and conservation of the remaining forest is a priority and having an appropriate environmental policy is mandatory for this purpose. Conservation actions in the temperate rainforest have been addressed from an individual species perspective, giving less attention to the ecosystem level conservation. Moreover, conservation-related information has not reflected yet on environmental policy development. We used the case study of the monito del monte (Dromiciops gliroides to illustrate how our current ecological and conservation knowledge of a species could be used to generate a new environmental policy. Dromiciops gliroides is a forest-dependent species with an important ecological role and quite unique evolutionary status. In order to guarantee the persistence of D. gliroides, we propose two habitat management components to be incorporated in management plans: structure and connectivity. Structure refers to spatial arrangement and key structural elements that determine habitat quality and connectivity refers to functional connectivity at the landscape level. The conservation of the monito del monte might also contribute to the conservation of many other forest-dependent species. By conserving such species it will be possible to conserve the ecological interactions and the eco-evolutionary processes, which ultimately determine the conservation of the temperate rainforest.El cambio de uso de la tierra es una de las principales amenazas a la biodiversidad. Hábitats naturales como el bosque templado lluvioso de Sudamérica han sido degradados, fragmentados y eliminados rápidamente. En consecuencia, es prioritario el manejo y conservación de los remanentes, para lo que es necesario contar con una política ambiental acorde. Las acciones de conservación referentes al bosque lluvioso templado se han abordado mayormente desde una perspectiva de especies individuales, con poco énfasis en la conservación a nivel de ecosistema. Más aún, la información generada en este ámbito tampoco ha permeado en el desarrollo de políticas ambientales. Utilizamos el estudio de caso del monito del monte (Dromiciops gliroides para ilustrar cómo el conocimiento actual en ecología y conservación de una especie puede ser utilizado para generar una nueva política ambiental. Dromiciops gliroides es una especie dependiente del bosque, con un importante rol ecológico y un gran interés evolutivo y de conservación. Para garantizar su persistencia, proponemos dos componentes de gestión del hábitat, a incorporarse en los planes de manejo: la estructura y la conectividad. La estructura hace referencia al arreglo espacial y la presencia de elementos estructurales clave que influyen en la calidad del hábitat, mientras que conectividad se refiere a la conectividad funcional del paisaje. Conservando al monito del monte, se conservarían también otras especies dependientes del bosque y así las interacciones ecológicas y los procesos ecoevolutivos, que determinan finalmente la conservación del bosque lluvioso templado.

  8. Percepción de alimentos en el primer lustro de vida: aspectos innatos, causalidad y modificaciones derivadas de la exposición / Food perception in the first lustrum of life: innate aspects, causality and modifications derived from repeated experiencies.

    Alejandro Chacón Villalobos

    2011-01-01

    ResumenEste trabajo de revisión bibliográfica describe el concepto de la percepción sensorial innata de los niños y niñas hacia los alimentos, así como los procesos por medio de los cuales esta se modifica y enriquece a través de la interacción y las experiencias alimentarias durante el primer lustro de vida. Además, la importancia del marco afectivo y social en el que este proceso formativo se da. Tanto los espacios y contextos donde se consumen y se promocionan los alimentos durante la eda...

  9. Análise macroscópica e histológica do emprego da poliuretana derivada do óleo de mamona (Ricinus communis aplicada na tíbia de cães em fase de crescimento Macroscopic and histopathologic evaluations of the use of polyurethane resins derived from castor oil (Ricinus communis applied in the tibia of the puppies

    Patricia Popak Maria

    2003-08-01

    Full Text Available OBJETIVO: Estudar o efeito da poliuretana de mamona aplicada ao osso de cães em crescimento. MÉTODOS: Foram utilizados 12 cães subdivididos aleatoriamente em 3 grupos, os quais receberam o implante de mamona na face medial proximal da tíbia, com análise macroscópica e histopatológica aos 30 (GIII, 60 (GII e 90 (GI dias. RESULTADOS: A poliuretana foi recoberta por uma cápsula conjuntiva fibrosa, não ocorrendo proliferação óssea ao seu redor. CONCLUSÃO: A poliuretana é biocompatível, comportando-se como espaçador biológico em cães. Nesta espécie não ocorre a osteointegração.PURPOSE: To analyze the effects of castor oil derived poliurethane, when applied to bones of puppies. METHODS: Twelve dogs, randomly divided in 3 groups, received a castor oil derived poliurethane at the medial side of the proximal tibia. Gross and histopathologic evaluations were performed at 30 (GIII, 60 (GII and 90 (GI days. RESULTS: The poliurethane was enclosed in a connective fibrous tissue capsule and there was no new bone formation around it. CONCLUSION: The castor oil derived poliurethane is biocompatible and behaves as a biological "stand off" in dogs. Osteointegration does not occur in this species.

  10. Técnica da peroxidação para a determinação de metionina em amostras derivadas de ensaios de digestibilidade do trigo e seus subprodutos em frangos de corte The peroxidation technique for methionine determination in derived samples of digestibility assays of the wheat and its by-products in broilers chickens

    Leonardo Boscoli Lara

    2005-04-01

    Full Text Available Realizou-se um experimento com excreta de aves usando comparar técnicas de hidrólise de aminoácidos com ou sem peroxidação prévia para determinação de metionina. O delineamento experimental foi inteiramente ao acaso, em esquema fatorial 2 x 4 x 8, (métodos x tratamentos x alimentos com três repetições. Sete alimentos oriundos do trigo e uma ração-referência foram utilizados nos quatro tratamentos. Os dois primeiros tratamentos foram baseados na metodologia tradicional de consumo à vontade e utilizou-se o método da alimentação forçada com aves intactas e aves cecectomizadas nos tratamento 3 e 4, respectivamente. Somente a técnica de peroxidação da amostra com ácido perfórmico seguida de hidrólise apresentou resultados confiáveis na análise de biodisponibilidade e conteúdo de metionina do trigo e seu subprodutos.One experiment was conducted with broiler chickens, for evaluation of metabolizable methionine and its levels in the wheat and some of its products, comparing two analyses techniques of methionine determination; hydrolyze and peroxidation with performic acid before hydrolyze. The broilers were randomly distributed in factorial outline 2 x 4 x 8, (methods x treatments x feeds with three repetitions. Seven feeds by-products of wheat grain were used in the four treatments. The first two treatments were set in the traditional methodology of ad libitum consumption and in the treatments three and four, the method of forced feeding was used. The treatment four were tested in the caecectomised chickens. The results of this experiment suggested that only the peroxidation with performic acid before hydrolyze showed good result in measure metabolizable methionine and its levels of wheat and its by-products.

  11. "Discovering the Cell": An Educational Game about Cell and Molecular Biology

    Spiegel, Carolina N.; Alves, Gutemberg G.; Cardona, Tania da S.; Melim, Leandra M. C.; Luz, Mauricio R. M. P.; Araujo-Jorge, Tania C.; Henriques-Pons, Andrea

    2008-01-01

    The role of games within education becomes clearer as students become more active and are able to take decisions, solve problems and react to the results of those decisions. The educational board game "Discovering the Cell" ("Celula Adentro"), is based on problem-solving learning. This investigative game attempts to stimulate…

  12. O Prêmio Nobel de Medicina e Fisiologia de 2012 quebrou o paradigma sobre a reversão do genoma e abre portas à Medicina do futuro.

    José Garcia Ribeiro Abreu Júnior

    2013-01-01

    Full Text Available Este editorial apresenta a revisao cientifica sobre o premio Nobel de Fisiologia e Medicina de 2012 conferido aos pesquisadores Jonh Gurdon e Shynia Yamanaka. No editorial e discutido com se chegou a descoberta sobre a reprogramacao do genoma e seus impactos na medicina do futuro baseada em celulas tronco.

  13. Opioid system manipulation during testicular development: results on sperm production and sertoli cells population = Manipulação do sistema opioidérgico durante o desenvolvimento testicular: consequência sobre a produção espermática e a população de células de sertoli

    Fernanda Mafra Cajú

    2011-04-01

    Full Text Available The Sertoli cell has fundamental importance to the development andmaintenance of spermatogenesis, as well as it has a directly proportional numerical relationship to sperm production. The proliferative period of this cell in rats occurs between 13 days pre-natal and 21 days pos-natal, when is established the final population in adult animals. The Leydig cell can modulate the Sertoli cell proliferation during fetal and neonatal periodƒn throughƒnƒnƒÒ-endorphin. The manipulation of opioidergic system can promote changes in parameters related to development of nervous, endocrine andreproductive systems. By the way, the main purpose of this present work was to compare the effects of the blockade of opioid receptor blocking in Sertoli cells using naltrexone (50 mg kg-1 during fetal and neonatal period in Wistar rats. According to the results, themanipulation of opioidergic system during pre-natal period reduced the total length of seminiferous tubule and Sertoli cell population in adult rats, but sperm production was normal because this cell has had a compensatory response for spermatozoids support capacity.As celulas de Sertoli tem fundamental importancia para o desenvolvimento e manutencao da espermatogenese, bem como possuem uma relacao numerica diretamente proporcional com a producao espermatica. O periodo proliferativo destas celulas em ratos ocorre entre 13 dias pre-natal e 21 dias pos-natal, resultando na definicao da populacao decelulas de Sertoli nos animais adultos. As celulas de Leydig podem modular a proliferacao das celulas de Sertoli durante o periodo fetal e neonatal por meio da ƒÒ-endorfina. A manipulacao do sistema opioidergico durante esta fase pode promover alteracoes em parametros relacionados com o desenvolvimento dos sistemas nervoso, endocrino ereprodutivo. Em virtude disto, o objetivo do presente trabalho foi comparar os efeitos do bloqueio de receptores opioides nas celulas de Sertoli, utilizando o naltrexone (50 mg kg

  14. A bone tissue engineering strategy based on starch scaffolds and bone marrow cells cultured in a flow perfusion bioreactor

    Gomes, Maria Manuela Estima

    A Engenharia de Tecidos e uma area cientifica em continua expansao. Os desenvolvimentos conseguidos por esta area tem contribuido significativamente para diversos avancos no campo da Medicina Regenerativa. Esta ciencia interdisciplinar combina os conhecimentos de diversas outras areas, tao distintas como a Engenharia de Materiais e a Biologia, com o objectivo de desenvolver substitutos sinteticos para tecidos humanos. Para se atingir este objectivo utilizam-se, de uma forma generica, combinacoes especificas de celulas e de um material de suporte tridimensional com propriedades adequadas, gerando um material hibrido cujas caracteristicas podem ainda ser moduladas atraves do sistema de cultura usado. A presente tese e centrada no desenvolvimento de estrategias de engenharia de tecido osseo baseadas na cultura in vitro de celulas previamente "semeadas" num suporte tridimensional ("scaffold"). Esta estrategia permite que as celulas adiram ao suporte, proliferem e segreguem matriz extracelular especifica do tecido osseo, ate se obter um substituto artificial funcional com caracteristicas do tecido original, que pode finalmente ser transplantado para tratar o defeito em causa. Para que uma estrategia deste tipo seja bem sucedida, pelo menos tres componentes fundamentais devem ser cuidadosamente estudados: o material de suporte (scaffold), as celulas a usar e o sistema de cultura in vitro. Dai que os principais objectivos desta tese estejam relacionados com estes tres aspectos, nomeadamente: • Desenvolvimento de scaffolds biodegradaveis a partir de polimeros a base de amido de milho que induzam a adesao e proliferacao celular e que apresentem propriedades adequadas, tais como a porosidade e interconectividade entre poros, de forma a proporcionar um ambiente que favoreca o desenvolvimento in vitro de um material hibrido com caracteristicas similares ao osso humano. • Estudo da utilizacao de celulas da medula ossea como uma potencial fonte de celulas para engenharia do

  15. Analysis for impedance electrochemistry 'on-line' of membrane/electrode assemble (MEA) of protons exchange membrane fuel cells (PEMFC); Analise por impedancia eletroquimica 'on-line' de conjuntos eletrodos/membrana (MEA) de celulas a combustivel a membrana polimetrica (PEMFC)

    Santos, Antonio Rodolfo dos

    2007-07-01

    This work reports results of studies and characterization on membrane electrode assemblies (MEAs) for proton exchange membrane fuel cell (PEMFC). Some cell operation conditions and different processes of MEA production were investigated. The electrochemical impedance spectroscopy technique (EIS) (in situ - 0 to 16 A) was used 'on-line' as a tool for diagnosis, concerning the cell performance. The EIS measurements were carried out with a FC350 Fuel Cell EIS System (GAMRY), coupled to a PC4 potentiostat/galvanostat and connected to the electronic load (TDI) for 'on-line' EIS experiments (100 mHz - 10 kHz, dU = 5 mV). MEAs with 25 cm{sup 2} surface area, using PtM/C 20% (M Ru, Sn or Ni) electrocatalysts were manufactured using the alcohol reduction process (ARP). The catalytic ink was applied directly into the carbon cloth (GDL) and pressed in the Nafion membrane (105). MEAs using Pt/C and Pt Ru/C 20% from E-TEK electrocatalysts were manufactured by comparison. All the cathodes were sprayed with Pt/C 20% from E-TEK. The noble metal concentrations used were set to 0.4 mg Pt.cm{sup -2} at the anode and 0.6 mg Pt.cm{sup -2} at the cathode (E-TEK). Nyquist diagrams of the MEAs with Pt/C and PtRu/C from E-TEK or PtM/C (M = Ru, Sn or Ni) ARP showed essentially the same ohmic resistances for the MEAs. This fact can be explained by suppression of agglomerates during the MEA preparation process or by the homogeneity of the anchored electrocatalysts at the carbon surface. It could also be observed, at low current densities, that there was a significant performance difference between the electrocatalysts from E-TEK and those prepared with the alcohol reduction process. The polarization curves results confirmed that the Pt M/C (M = Ru, Sn or Ni) ARP showed an activity increase for the methanol and ethanol fed cells. The technique of EIE was shown efficient for the evaluation of the method preparation of MEAs and the acting of the cell, the results of EIE showed coherence in the choice of the model the electric circuit for MEAs using hydrogen, methanol and ethanol. This coherence indicates that other resistances no considered in the model are not relevant in the total resistance of MEAs. (author)

  16. Resistance to the ionizing radiation in cells of human melanoma. Role of the antioxidant enzymes and of the free radicals of the oxygen; Resistencia a la radiacion ionizante en celulas de melanoma humano. Papel de las enzimas antioxidantes y de los radicales libres del oxigeno

    Medina, V; Cricco, G; Massari, N; Nunez, M; Martin, G; Mohanad, N; Gutierrez, A; Bergoc, R; Rivera, E [Laboratorio de Radioisotopos, Facultad de Farmacia y Bioquimica, Universidad de Buenos Aires, Junin 956, Buenos Aires (Argentina); Crescenti, E; Croci, M [Instituto de Inmunooncologia, Cordoba 3200, Buenos Aires (Argentina)

    2006-07-01

    The malignant melanoma is a highly aggressive and potentially lethal type of skin cancer. Previously we have reported that the cellular human lines of melanoma WM35 and M15 are resistant to the ionizing radiation (IR). The histamine (HA) although it has a regulator effect of the cellular proliferation in these lines, it is not capable of to modify the response to the IR like it makes with other malignant cellular lines. To investigate the bases of the radioresistance of the melanoma lines we have studied in the WM35 the production of free radicals of oxygen (ROS), the activity of the antioxidant enzymes and their modifications by action of the IR and of the HA. In studies in vitro the cells were treated with HA 10 {mu}M from 20 hs before being irradiated with a dose of 2 Gy (source {sup 137}Cs, dose rate 7.7 Gy/min). The ROS levels, superoxide anion (O{sub 2}{sup -}) and hydrogen peroxide (H{sub 2}O{sub 2}) its were measured by flow cytometry using fluorescent coloring and the activity of dismutase superoxide (SOD), Catalase (CAT) and Glutathion Peroxidase (GPx) its were determined by spectrophotometric techniques and the protein levels by Western blot. The results indicate that in the cells WM35 the HA increases the production of H{sub 2}O{sub 2} in 96% and it diminishes lightly (17%) the levels of O{sub 2}{sup -} . On the contrary, the IR diminishes the levels of H{sub 2}O-2 in 47% and it increases in 46% those of O{sub 2}{sup -}. In the irradiated cells the HA power the decrease of H{sub 2}O{sub 2} produced by the IR. The variation of the enzymes activity is coincident with these changes in the levels of ROS: the treatment with HA increases the activity of SOD and it diminishes that of CAT in cells without irradiating; on the other hand, in the irradiated cells the HA it diminishes the SOD significantly. On the base of these results we can conclude that the levels of H{sub 2}O{sub 2} are directly related with the sensitivity of the cells WM35 to the IR. The HA is able to modulate the activity of the antioxidant enzymes and the levels of ROS. The IR activates cellular mechanisms that take to the radioresistance of these cells and that its interfere and/modifying the biological response mediated by the HA. (Author)

  17. Labeling of vasoactive intestinal peptide (VIP) and VIP 10-28 fragment with radioiodine by direct method. Comparative study of the kinetics biodistribution and affinity for neuroendocrine tumor cells; Marcacao do peptideo intestinal vasoativo (VIP) e do fragmento VIP10-28 com radioiodo por metodo direto. Estudo comparativo da cinetica de biodistribuicao e da afinidade por celulas de tumor neuroendocrino

    Colturato, Maria Tereza

    2005-07-01

    In the progress of the Nuclear Medicine, many protein based radiopharmaceuticals have been developed in the last years using antibodies and, more recently, biologically active natural peptides or similar synthetic peptides. In the search for agents with specificity for the target tissue in tumors detection, it was verified that small sequences of amino acids may interact with selective sites, with homogenous distribution, fast accumulation in tissues and fast blood clearance when compared to the antibodies. Among the peptides used in the diagnosis of tumors, Vasoactive Intestinal Peptide (VIP) has been studied. VIP labeled with iodine-123 is applied in the images of intestinal adenocarcinoma and endocrine tumors. The molecule of VIP contains two tyrosine residues, in the positions 10 and 22 that are, theoretically, equally susceptible to radioiodination for direct method. The objective of this work was to produce VIP labeled with radioiodine (iodine-123), in order to introduce to the brazilian medical class this radiopharmaceutical of interest for the diagnosis and recurrence of tumors that express specific receptors. In an unpublished way, the work studied the labeling and the kinetic distribution of the VIP fragment (VIP 10-28) and verified its potential as radiopharmaceutical applied in the identification of tumors that express VIP receptors. After the choice of the appropriated technique for labeling VIP and VIP 10-28 with radioiodine, using Ceremonial T as oxidant agent and sodium metabisulfite as reducing agent, the quality control procedures were accomplished (electrophoresis and high performance liquid chromatography, HPLC) for radiochemical purity determination as well as the separation of the radiochemical species obtained. Labeling and quality control procedures applied were efficient and accurate. [{sup 131}I]VIP and [{sup 131}l]VIP 10-28 were obtained with high radiochemical purity (> 95%). The purification studies to remove free radioiodine in the labeling mixture (simple purification) and to produce the radiopharmaceutical with high specific activity (complex purification and HPLC), were both efficient in the separation of the species in the reaction mixtures, as demonstrated by quality control procedures. Biological distribution studies were accomplished by venous administration of the radiopharmaceuticals in laboratory animals: biodistribution study of [{sup 131}I]VIP and [{sup 131}I]VIP 10-28 in normal Swiss mice, [{sup 131}I]VIP not purified and purified in Swiss mice with tumor and [{sup 131}I]VIP and [{sup 131}I]VIP 10-28 in Nude mice with tumor, scintigraphic images of [{sup 131/123}I]VIP and [{sup 123}I]VIP 10-28 in Swiss and Nude mice and Wistar rats with tumor. In vitro studies were accomplished to determine the percentage of [{sup 131}I]VIP and [{sup 131}I]VIP 10-28 bound to plasmatic proteins, stability study of [{sup 131}I]VIP and [{sup 131}I]VIP 10-28 in human plasma and the affinity and internalization of [{sup 131}I]VIP and [{sup 131}I]VIP 10-28 by tumour adenocarcinoma cells of human rectal colon (HT-29). All biological distribution studies demonstrated that both [{sup 131/123}I]VIP and [{sup 131/123}I]VIP 10-28 showed fast blood clearance, low renal and liver uptake, relative uptake in thyroid, showing in vivo dehalogenation and good uptake in tumour. Comparative biological distribution of the radiopharmaceuticals showed high uptake in the stomach for both peptides. The blood clearance of the fragment was slower, and influences the visualization of the tumour mass. The radiopharmaceuticals, [{sup 123}I]VIP and [{sup 123}I]VIP 10-28, were obtained with high radiochemical purity, but with low radiochemical yield when comparing with labeling procedures using iodine-131. Quality control assays of [{sup 123}I]Na indicated that the presence of radiochemical and radionuclide impurities influenced on labeling results. (author)

  18. Prepared thin laminae of CuInS{sub 2} by means of evaporation in flow modulated for its application like absorbents in solar cells; Laminas delgadas de CuInS{sub 2} preparadas mediante evaporacion en flujo modulado para su aplicacion como absorbentes en celulas solares

    Bollero, A.; Trigo, J. F.; Herrero, J.; Gutierrez, M. T.

    2008-07-01

    The Department of energy of CIEMAT focuses one of its research lines on the preparation of CuInS{sub 2} films to be used as absorber in solar cells. this work shows the influence of the different process parameters (deposition sequence, modulation of the evaporation flux of the constituent elements,...) on the morphology and the optical properties of the final films. A simplified evaporation procedure has allowed the preparation of CuInS{sub 2} films with a low Cu content. this avoids the necessity of applying subsequent toxic treatment for removal of the CuS phase prior to implementation of the film as absorber in the solar cell device. (Author)

  19. Intracellular labeling and quantification process by magnetic resonance imaging using iron oxide magnetic nanoparticles in rat C6 glioma cell line; Marcacao intracelular e processo de quantificacao por imagem por ressonancia magnetica utilizando nanoparticulas magneticas de oxido de ferro em celulas da linhagem C6 de glioma de rato

    Mamani, Javier Bustamante; Pavon, Lorena Favaro; Sibov, Tatiana Tais; Rossan, Fabiana; Silveira, Paulo Henrique; Cardenas, Walter Humberto; Gamarra, Lionel Fernel, E-mail: javierbm@einstein.br [Instituto do Cerebro - InCe, Hospital Israelita Albert Einstein - HIAE, Sao Paulo, SP (Brazil); Miyaki, Liza Aya Mabuchi [Faculdade de Enfermagem, Hospital Israelita Albert Einstein - HIAE, Sao Paulo, SP (Brazil); Amaro Junior, Edson [Departamento de Diagnostico por Imagem e Instituto do Cerebro - InCe, Hospital Israelita Albert Einstein - HIAE, Sao Paulo, SP (Brazil)

    2012-04-15

    Objective: To assess intracellular labeling and quantification by magnetic resonance imaging using iron oxide magnetic nanoparticles coated with biocompatible materials in rat C6 glioma cells in vitro. These methods will provide direction for future trials of tumor induction in vivo as well as possible magnetic hyperthermia applications. Methods: Aminosilane, dextran, polyvinyl alcohol, and starch-coated magnetic nanoparticles were used in the qualitative assessment of C6 cell labeling via light microscopy. The influence of the transfection agent poly-L-lysine on cellular uptake was examined. The quantification process was performed by relaxometry analysis in T{sub 1} and T{sub 2} weighted phantom images. Results: Light microscopy revealed that the aminosilane-coated magnetic nanoparticles alone or complexed with poly-L-lysine showed higher cellular uptake than did the uncoated magnetic particles. The relaxactivities of the aminosilane-coated magnetic nanoparticles with a hydrodynamic diameter of 50nm to a 3-T field were r{sub 1}=(6.1 +- 0.3) x10{sup -5} ms{sup -1}mL/{mu}g, r{sub 2}=(5.3 +- 0.1) x 10{sup -4} ms{sup -1}mL/{mu}g, with a ratio of r{sub 2} / r{sub 1}{approx_equal} 9. The iron uptake in the cells was calculated by analyzing the relaxation rates (R{sub 1}and R{sub 2}) using a mathematical relationship. Conclusions: C6 glioma cells have a high uptake efficiency for aminosilane-coated magnetic nanoparticles complexed with the transfection agent poly-L-lysine. The large ratio r{sub 2} / r{sub 1}{approx_equal} 9 indicates that these magnetic nanoparticles are ideal for quantification by magnetic resonance imaging with T{sub 2}-weighted imaging techniques. (author)

  20. Activación de celulas supresoras de la respuesta de hipersensibilidad tardía en ratones BALB/c infectados o vacunados con Leishmania mexicana pifanoi Activation of supressor cells of delayed hypersensitivity response in BALB/C mice infected or immunized with Leishmania mexicana pifanoi

    Hilda A. Pérez

    1985-12-01

    Full Text Available Los ratones BALB/c inmunizados SC con promastigotes no viables de Leishmania mexicana pifanoi, desarrollaron respuestas de hipersensibilidad tardia (RHT contra el parásito. En contraposición, los ratones BALB/c infectados crónicamente con L.m. pifanoi y aquellos inmunizados IV con una dosis supraóptima de parásitos muertos, mostraron inhibición de la RHT. La supresión de la RHT en los animales infectados, estuvo precedida por un estado transitorio de inmunidad celular, manifestado durante la fase inicial del desarrollo de las lesiones (4-12 semanas. La inhibición de la RHT observada en los animales infectados o inmunizados con dosis supraóptimas, fue causada por un mecanismo activo, transferible a receptores singénicos a través de las células esplénicas de los donantes suprimidos. La población de células supresoras fue no adherente a "nylon", sensible al tratamiento con un suero anti-timocitos de ratón y C', y de acción específica sobre la RHT contra antígenos leishmánicos. Se propone que la ocurrencia de células T supresoras de la RHT en los animales infectados crónicamente o inmunizados con dosis supraóptimas, es causada por el exceso de carga antigénica. Esta última, en el caso de los animales infectados, secundaria a una falla primaria en el control inmunológico de la población parasitaria.A T suppressor cell population that specifically shut down delayed hypersensitivity responses (DHR to the parasite was found in both BALB/c mice chronically infected with Leishmania mexicana pifanoi and in naive mice which had received a single IV supraoptimal dose of killed parasites. At the early phase of infection mice exhibited a transitory state of cell-mediated immunity against the parasite that was abrogated when lesions reached their accelerated phase of growth. Results suggest that in both infected and high-dose immunized mice, the activation of T suppressor cells of DHR is related to antigen overload.

  1. Determination of boron by ICP-AES in normal and malignant cells incubated 'in vitro' with fructose {sup 10}BPA; Determinacion de boro por ICP-AES para el estudio de captacion por celulas malignas y normales incubadas 'in vitro' con fructosa-BPA

    Garavaglia, Ricardo N; Farias, Silvia S; Rodriguez, Ruben E; Servant, Roberto E; Liberman, Sara; Pisarev, Mario A; Batistoni, Daniel A [Comision Nacional de Energia Atomica, General San Martin (Argentina). Dept. de Quimica

    1999-07-01

    This paper describes the development and optimization of methodology for total boron concentration in cell cultures coming from fixation and accumulation of this element by normal and malignant cells. On account of sample mass and low volume resulting from dilution, generally about 1 mL, a procedure for automatic injection of micro volumes was designed, developed and optimized. Iron interference was carefully studied. Linear calibration curves were obtained for 50 to 2500 ng B/mL range. Determination limits were 10 and 20 ng B/mL for B 249.772 nm and 249.677 nm, respectively. Repeatability, expressed as relative standard deviation was better than 5% for a 100 ng B/mL. Recovery of analyte added to real samples ranged between 95 and 103%. The method was applied to studies on F-98 cells (rat glioma) and normal glia in BNCT project frame. (author)

  2. Fluorescein isothiocyanate labeled, magnetic nanoparticles conjugated D-penicillamine-anti-metadherin and in vitro evaluation on breast cancer cells; Avaliacao do isotiocianato de fluoresceina marcado, das nanoparticulas magneticas conjugadas da D-penicilamina antimetaderina e in vitro nas celulas do cancer de mama

    Akca, Ozlet; Unak, Perihan; Medine, E. Ylker [Ege University (Turkey). Institute of Nuclear Sciences. Department of Nuclear Applications; Sakarya, Serhan [Adnan Menderes University (Turkey). ADUBILTEM Science and Technology Research and Development Center; Ozdemir, Caglar; Timur, Suna [Ege University (Turkey). Science Faculty. Department of Nuclear Applications

    2011-07-01

    Silane modified magnetic nanoparticles were prepared after capped with silica generated from the hydrolyzation of tetraethyl orthosilicate (TEOS). Amino silane (SG-Si900) was added to this solution for surface modification of silica coated magnetic particles. Finally, D-penicillamine (D-PA)-antimetadherin (anti-MTDH) was covalently linked to the amine group using glutaraldehyde as cross-linker. Magnetic nanoparticles were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), vibrating sample magnetometer (VSM), and atomic force microscopy (AFM). AFM results showed that particles are nearly monodisperse, and the average size of particles was 40 to 50 nm. An amino acid derivative D-PA was conjugated anti-MTDH, which results the increase of uptaking potential of a conjugated agent, labelled fluorescein isothiocyanate (FITC) and then conjugated to the magnetic nanoparticles. In vitro evaluation of the conjugated D-PA-anti-MTDH-FITC to magnetic nanoparticle was studied on MCF-7 breast cancer cell lines. Fluorescence microscopy images of cells after incubation of the sample were obtained to monitor the interaction of the sample with the cancerous cells. Incorporation on cells of FITC labeled and magnetic nanoparticles conjugated D-PA-anti-MTDH was found higher than FITC labeled D-PA-anti-MTDH. The results show that magnetic properties and application of magnetic field increased incorporation rates. The obtained D-PA-anti-MTDH-magnetic nanoparticles-FITC complex has been used for in vitro imaging of breast cancer cells. FITC labeled and magnetic nanoparticles conjugated D-PA-anti-MTDH may be useful as a new class of scintigraphic agents. Results of this study are sufficiently encouraging to bring about further evaluation of this and related compounds for ultraviolet magnetic resonance (UV-MR) dual imaging. (author)

  3. Induced thermal ablation with a radiofrequency field in breast cancer cells using gold nanoparticles conjugated to the peptide cycle[RGDfK(C)]; Termoablacion inducida con un campo de radiofrecuencia en celulas de cancer de mama utilizando nanoparticulas de oro conjugadas al peptido ciclo[RGDfK(C)

    Sanchez H, L.

    2014-07-01

    The conjugation of peptides to gold nanoparticles (AuNP) produces biocompatible and stable multimeric systems with target-specific molecular recognition. Peptides based on the cyclic Arg-Gly-Asp (RGD) sequence have been reported as high-affinity agents for the α(v)β(3) and α(v)β(v) integrin s over expressed in breast cancer cells. AuNP have also been proposed as localized heat sources for cancer treatment using laser irradiation or radiofrequency (RF). The objective of this research was to evaluate the thermo ablative effect of the AuNP-c [RGDfK(C)] system on MCF7 breast cancer cell viability after exposure to a radiofrequency field and to compare it with that produced by the laser irradiation. The effect of the 13.56 MHz RF (using a power from 0 to 200 W at intervals of 50 W) over the temperature increase in AuNP-colloidal system of 5 and 20 nm at two different concentrations was evaluated. The absorption cross sections (C{sub abs}) of the AuNP-c [RGDfK(C)] nano system when it interacts with low frequency electromagnetic waves (13.56 MHz, λ = 22 m) and optical frequency waves (laser at λ = 532 nm) was analyzed based on the Mi e theory. The effect on the MCF7 cell viability was assessed using two thermal conversion sources (Laser and RF) on AuNP-c [RGDfK(C)] located inside the cytoplasm of the cells. MCF7 cells were treated with AuNP-c [RGDfK(C)] or water after exposure to the RF field (200 W, 100 V/cm) or laser irradiation (Irradiance 0.65 W/cm{sup 2}). In both cases (RF and laser) the presence of nanoparticles internalized inside the cells caused a significant increase in the temperature of the medium (RF: ΔT = 29.9 ± 1.7 grades C for AuNP compared toΔT = 13.0 ± 1.4 grades C for water; laser: ΔT = 13.5 ± 0.7 grades C for AuNP compared to 3.3 ± 0.5 grades C for water). Although RF induced a higher increase in the temperature of the medium with nanoparticles, the largest effect on the cell viability was produced by laser when nanoparticles were located inside the cells (8.7 ± 0.7 % for laser compared to 19.4 ± 0.9 % for RF). The differences obtained in C{sub abs} values (laser: 3.7x10{sup -16} m{sup 2}; RF: 7.9x10{sup -23} m{sup 2}) and the observed effect on MCF7 cell viability support two mechanisms proposed -optical frequency wave energy absorption by AuNP- when laser is used as a thermal conversion source, and -energy attenuation of the low frequency electromagnetic wave propagating through the AuNP-colloidal system- when RF field is applied. The AuNP-c[RGDfK(C)] nano system shows suitable properties to improve hyperthermia treatments under laser irradiation due to a larger heat release inside cells. (Author)

  4. Life cycle assessment (LCA) methodology: importance in the integration of the fuel cell technology type PEMFC (proton exchange membrane fuel cells); Metodologia da analise de ciclo de vida: importancia na insercao da tecnologia de celula a combustivel do tipo PEMFC (membrana polimerica trocadora de protons)

    Fukurozaki, Sandra Harumi; Seo, Emilia Satoshi Miyamaru [Instituto de Pesquisas Energeticas e Nucleares (IPEN-CNEN/SP), Sao Paulo, SP (Brazil)). Centro de Ciencia e Tecnologia de Materiais], e-mail: shfukuro@ipen.br

    2004-07-01

    To improve the standard of society's quality of life, it is necessary to improve the quality of distributed energy and its inherent services within a sustainability process. Among different technological routes that produce more sustainable energy are the fuel cells - also known as combustible batteries. The Global Environment Facility (GEF) has identified the fuel cells as a potential technology to reduce, in the future, the effect of greenhouse gases in both developed and developing countries. Although there are various types of fuel cells, the most used technology for research studies on fuel cells is the Polymer Electrolyte Fuel Cells (FEMFC). However, economic issues - related to the high cost of the membrane's materials and of the catalysts of groups of platinum metals - are still some of the obstacles that need to be overcome for this technology to be more accessible. There are also socio-environmental aspects related to the impacts caused by the extraction, the use and the destination of these metals. Taking in consideration the challenges of complying with the demands of the market and the society as well as with the growing tendency of more rigid patterns of environmental control, the objective of the present work is to show the tool of environmental management - Life Cycle Assessment (LCA) - and its importance on the pursuit for socio-economic and environmental alternatives feasible to the recycling of the catalysts of platinum of the PEMFC. This way, it intends to collaborate to the progress of the knowledge about environmental and socio-economic subjects related to the productive process of the PEMFC. (author)

  5. Study and development of membrane electrode assemblies for Proton Exchange Membrane Fuel Cell (PEMFC) with palladium based catalysts; Estudo e desenvolvimento de conjuntos membrana-eletrodos (MEA) para celula a combustivel de eletrolito polimerico condutor de protons (PEMFC) com eletrocatalisadores a base de paladio

    Bonifacio, Rafael Nogueira

    2013-07-01

    PEMFC systems are capable of generating electricity with high efficiency and low or no emissions, but durability and cost issues prevent its large commercialization. In this work MEA with palladium based catalysts were developed, Pd/C, Pt/C and alloys PdPt/C catalysts with different ratios between metals and carbon were synthesized and characterized. A study of the ratio between catalyst and Nafion Ionomer for formation of high performance triple-phase reaction was carried out, a mathematical model to implement this adjustment to catalysts with different relations between metal and support taking into account the volumetric aspects of the catalyst layer was developed and then a study of the catalyst layer thickness was performed. X-ray diffraction, Transmission and Scanning Electron Microscopy, X-ray Energy Dispersive, Gas Pycnometry, Mercury Intrusion Porosimetry, Gas adsorption according to the BET and BJH equations, and Thermo Gravimetric Analysis techniques were used for characterization and particle size, specific surface areas and lattice parameters determinations were also carried out. All catalysts were used on MEAs preparation and evaluated in 5 cm{sup 2} single cell from 25 to 100 °C at 1 atm and the best composition was also evaluated at 3 atm. In the study of metals for reactions, to reduce the platinum applied to the electrodes without performance losses, Pd/C and PdPt/C 1:1 were selected for anodes and cathodes, respectively. The developed MEA structure used 0,25 mgPt.cm{sup -2}, showing power densities up to 550 mW.cm{sup -2} and power of 2.2 kW{sub net} per gram of platinum. The estimated costs showed that there was a reduction of up to 64.5 %, compared to the MEA structures previously known. Depending on the temperature and operating pressure, values from US$ 1,475.30 to prepare MEAs for each installed kilowatt were obtained. Taking into account recent studies, it was concluded that the cost of the developed MEA is compatible with PEMFC stationary application. (author)

  6. Study of the Nafion quantity effect in membrane and electrodes assemblies (MEAs) of 50 cm{sup 2} used in type proton exchange membrane (PEM) fuel cell operating with H{sub 2}/Air; Estudo do efeito da quantidade de Nafion em MEAs de 50 cm{sup 2} utilizadas em celula a combustivel tipo PEM operando com H{sub 2}/ar

    Profeti, Demetrius; Colmati, Flavio; Carlindo, Adao A.J.; Paganin, Valdecir A.; Gonzalez, Ernesto R.; Ticianelli, Edson A. [Universidade de Sao Paulo (USP), Sao Carlos, SP (Brazil). Inst. de Quimica]. E-mail: dprofeti@iqsc.usp.br

    2008-07-01

    The performance of a proton exchange membrane fuel cell (PEMFC) was investigated with the aim at characterizing the effects of the Nafion. content on the scale-up of the electrodes from 5 to 50 cm{sup 2}. It is observed that a diminution of the single cell performance occurred when the electrode area is increased from 5 to 50 cm{sup 2}. The tests carried out with different Nafion. contents, and fuel cell and humidifiers at the same temperature (T{sub cell}=T{sub H2}=T{sub air}=70 deg C) showed a slightly decrease of the fuel cell performance compared to the tests performed at different temperatures (T{sub cell}=70 deg C, T{sub H2}=85 deg C, T{sub air}=75 deg C). In the study of the variation on the Nafion. contents, the higher performance up to a current density of 0.8 A cm-2 is obtained with the 35.5 wt.% Nafion.. On the other hand, at higher current densities values, the performance of the fuel cells is very similar for the 31.0, 35.5 and 39.4 wt.% Nafion contents. (author)

  7. Preliminary analysis for implementation of a hybrid solar-wind system with storage of electrical energy generated through electrolytic hydrogen and fuel cells; Analise preliminar para implementacao de um sistema hibrido solar-eolico com armazenamento da energia eletrica gerada atraves de hidrogenio eletrolitico e celula a combustivel

    Lopes, Daniel Gabriel; Furlan, Andre Luis; Lopes, Davi Gabriel [Universidade Estadual de Campinas (FEM/UNICAMP), SP (Brazil). Fac. de Engenharia Mecanica], e-mail: danielg@fem.unicamp.br; Silva, Ennio Peres; Apolinario, Fernando Resende [Universidade Estadual de Campinas (IFGW/UNICAMP), SP (Brazil). Inst. de Fisica Gleb Wataghin. Lab. de Hidrogenio; Silva, Maria Eugenia Vieira da; Rocha, Paulo Alexandre Costa [Universidade Federal do Ceara (UFC), Fortaleza, CE (Brazil). Dept. de Engenharia Mecanica e de Producao; Codeceira Neto, Alcides [Companhia Hidro Eletrica do Sao Francisco (CHESF), Recife, PE (Brazil)

    2008-07-01

    Due to relevance of the study and applicability of hybrid electric power generation from solar photovoltaic and wind power in Brazil, the present paper aims to introduce briefly the importance of technical and economic comparison of two electrical energy storage technologies (batteries versus H2 + fuel cell) and also to indicate the previous difficulties related to this possible application. In this context, it was intended a partnership between State University of Campinas - UNICAMP, the Federal University of Ceara - UFC and Hydro Electric Company of the Sao Francisco - CHESF in the meaning of makes viable an implementation. (author)

  8. Locally advanced lung cancer non small cell (CBPLANPC): determination of the volumes of and tac mi bi radiotherapy: randomized phase II; Cancer de pulmon localmente avanzado no a pequeñas celulas(CBPLANPC): determinacion de los volumenes de radioterapia por mibi y tac: ensayo fase II

    Quarneti, A.; Alonso, O.; De Rosa, A.; García Fontes, M.; Luongo Gardi, A.; Castillo, C.; Delgado, L.; Pintado, D.; Dalla Rossa, M.; Guerrero, L.; Lillo, O.; Luongo Gardi, M.; Castaño, A.; Luongo, A.; De Trapani, E.; Torres, M. [Departamentos de Oncología, Imagenología, Medicina Nuclear del Hospital de Clínicas, Facultad de Medicina, Montevideo (Uruguay)

    2010-12-15

    Full text: However there are few clinical situations that allow treatment appropriate surgical. Chemoradiation treatment has shown results above, however the amount of radiation treatment in general is large, determines morbidity and limited in part to receive the final dose as already reported in previous Congresses Uruguayans Oncology 2000 and 2002 where it rarely Local control was obtained. They inform you of the need to limit treatment volumes radiant disease or biological tumor volume (VTB) using complementary imaging procedures. Objective: To determine the radiation treatment volumes contributing MIBI clarify the VTB. Compare those figures with those established by the TAC. To analyze the intra and extra faults VTB and analyze treatment with RT type ''Involved Field'' or involved field RT (IF) Materrial and Methods: This project Conclusions: This proposal identifies problems and opportunities, proposes institutional development of the SOR network under one management model.

  9. Exploratory study on the integration of fuel cell systems inside the chloro-soda plants for utilization of industrial hydrogen; Estudo exploratorio da integracao de sistemas de celula a combustivel dentro das plantas de cloro-soda para utilizacao do hidrogenio industrial

    Braga, Jose Mauro Fernandes [Universidade Federal Fluminense (UFF), Niteroi, RJ (Brazil). Escola de Engenharia]. E-mail: jmfbraga@oi.com.br; Seidl, Peter [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil); Pirro e Longo, Waldimir [Universidade Federal Fluminense (UFF), Niteroi, RJ (Brazil). Nwcleo de Estudos Estrategicos (NEST)

    2008-07-01

    This work aims to demonstrate the economic viability of the application of industrial hydrogen in fuel cell systems by analyzing the advantages and disadvantages of this investment in hydrochloric acid/ sodium hydroxide plants. Using the Present Liquid Value and the Real Options Theory an economic evaluation will be made of the integration of fuel cell system in these plants, based on investment cost, volatility, among other parameters. (author)

  10. Reduction of greenhouse gases emissions listed in the Kyoto Protocol by the utilization of landfill gas using solid oxide fuel cells; Reducao das emissoes de gases de efeito estufa listados no protocolo de Quioto pelo aproveitamento do gas gerado em aterros sanitarios utilizando celulas a combustivel de oxido solido. Estudo de caso do aterro municipal de Santo Andre, SP, Brazil

    Paris, Alexandre Gellert

    2007-07-01

    In the last few years, the Kyoto Protocol had been a subject very debated, at first, in a restricted niche, manly academics and professionals related to the area of climate changes. On 16th February 2005 the Kyoto Protocol entered into force and with this a lot of publicity all over the world, so today is common to hear about it at the mass communications media. The extension of the subject is broad, this work discuss the utilization of one the Kyoto's flexibility mechanisms, to contribute to financing the use of the landfill gas in the solid oxide fuel cells. Among the three mechanisms presented in the Kyoto Protocol, the clean development mechanism (CDM) in article 12, is the only one that can be implemented by non-Annex I countries, the case of Brazil. In other hand, the issue of solid waste in Brazil is critical. Even being illegal, most of the solid waste goes to uncontrolled areas in open air places 'lixoes', causing degradation of the environment and the communities around this areas, and also emission of green house gases (GHG), deregulating the global climate system. Decontaminate this areas and the construction of landfills to replace than, considering the landfill as a bioreactor, and the utilization of the biogas to generate power can improve nowadays picture that we are facing. The utilization of an innovative alternative technology as the solid oxide fuel cell (SOFC) instead the conventional technologies will be more efficient and environmentally better. Among other barriers the cost is pointed as the biggest. In this context, the SOFC is the most expensive fuel cell, so the utilization of CDM can contribute to finance the application of this technology. Scenarios were made of 250 kW, 500 kW, 1,000 kW, 5,000 kW and 10,000 kW of installed power using biogas from the Municipal Landfill of Santo Andre. The calculations of the emission factor were done ex ante and ex post according to ACM0002. Comparing the costs of the installed power studied and the calculation of the emission reduction, a potential income, the costs are superior, however, other incomes from the selling of energy and the disposal of solid waste most be taken into account in the process of decision of this type of projects. (author)

  11. Evidence about chlorophyllin can function as an inhibitor or promoter of induced genetic damage by gamma radiation in Drosophila somatic cells; Evidencia de que la clorofilina puede funcionar como un inhibidor o un promotor del dano genetico inducido por radiacion gamma en celulas somaticas de Drosophila

    Pimentel, A.E.; Cruces, M.P.; Zimmering, S.I. [Departamento de Biologia, ININ, A.P. 18-1027, 11801 Mexico D.F. (Mexico)

    2000-07-01

    The irradiation of the individuals that had been feed during 24 hours with a chlorophyllin solution at 5 % was delayed from 0 until 4 days. The protector effect of chlorophyllin persisted by 3 days and it appears to coincide with the stage when stopping the mitotic divisions in the imagal disk. Within of the same cellular population, it was demonstrated that chlorophyllin can function as an inhibitor, in the case of simple stains mwh or a potentiator in the case of twin stains and the flr type stains. It was planned an explanation for these results. (Author)

  12. Cost analysis of electrical power from an ethanol reformer and the fuel cell in the development of productive activities in the community Pico do Amor, MT, Brazil; Analise do custo da energia eletrica proveniente de um reformador de etanol e celula a combustivel no desenvolvimento de atividades produtivas na comunidade Pico do Amor/MT

    Lopes, Davi Gabriel; Teixeira, Andre Frazao; Lopes, Daniel Gabriel; Cavaliero, Carla Kazue Nakao [Universidade Estadual de Campinas (DE/FEM/UNICAMP), SP (Brazil). Faculdade de Engenharia Mecanica. Departamento de Energia; Instituto Aqua Genesis, Campinas, SP (Brazil); Hytron, Campinas, SP (Brazil)

    2010-07-01

    This work has the objective to analyze the impact of the cost of from an ethane reformer / fuel cell in the family income considering the development of two productive activities selected by the community itself: the production and marketing of cassava flour and 'rapadura', a typical brazilian candy. The community energy demand was analyzed to achieve the results; estimated the energy cost from the implemented system and the money from the selling of the cassava flour and 'rapadura' produced with this electricity; the study of sensibility of the ethanol price in the electrical energy cost was done too, and the cassava flour and 'rapadura' in the family funds. From the results, it was verified that the electrical energy cost has a 16,4% impact in the family gross income and a net value around R$ 260,85/family, indicating that the community will have enough funds to pay for the energy and also will rise the amount of money for each family. Besides, the comparative analyze of the cost of the electricity from the ethanol/fuel cell reformer and photovoltaic systems shows that, considering only the maintenance and operation costs, the first one should be more attractive than the second one. (author)

  13. Reduction of greenhouse gases emissions listed in the Kyoto Protocol by the utilization of landfill gas using solid oxide fuel cells; Reducao das emissoes de gases de efeito estufa listados no protocolo de Quioto pelo aproveitamento do gas gerado em aterros sanitarios utilizando celulas a combustivel de oxido solido. Estudo de caso do aterro municipal de Santo Andre, SP, Brazil

    Paris, Alexandre Gellert

    2007-07-01

    In the last few years, the Kyoto Protocol had been a subject very debated, at first, in a restricted niche, manly academics and professionals related to the area of climate changes. On 16th February 2005 the Kyoto Protocol entered into force and with this a lot of publicity all over the world, so today is common to hear about it at the mass communications media. The extension of the subject is broad, this work discuss the utilization of one the Kyoto's flexibility mechanisms, to contribute to financing the use of the landfill gas in the solid oxide fuel cells. Among the three mechanisms presented in the Kyoto Protocol, the clean development mechanism (CDM) in article 12, is the only one that can be implemented by non-Annex I countries, the case of Brazil. In other hand, the issue of solid waste in Brazil is critical. Even being illegal, most of the solid waste goes to uncontrolled areas in open air places 'lixoes', causing degradation of the environment and the communities around this areas, and also emission of green house gases (GHG), deregulating the global climate system. Decontaminate this areas and the construction of landfills to replace than, considering the landfill as a bioreactor, and the utilization of the biogas to generate power can improve nowadays picture that we are facing. The utilization of an innovative alternative technology as the solid oxide fuel cell (SOFC) instead the conventional technologies will be more efficient and environmentally better. Among other barriers the cost is pointed as the biggest. In this context, the SOFC is the most expensive fuel cell, so the utilization of CDM can contribute to finance the application of this technology. Scenarios were made of 250 kW, 500 kW, 1,000 kW, 5,000 kW and 10,000 kW of installed power using biogas from the Municipal Landfill of Santo Andre. The calculations of the emission factor were done ex ante and ex post according to ACM0002. Comparing the costs of the installed power studied and the calculation of the emission reduction, a potential income, the costs are superior, however, other incomes from the selling of energy and the disposal of solid waste most be taken into account in the process of decision of this type of projects. (author)

  14. Synthesis and evaluation in vitro in cancer cells AR42J of the radiopharmaceutical {sup 99m}Tc-Tyr{sup 3}-Octreotide-dendrimer similar of somatostatin; Sintesis y evaluacion in vitro en celulas de cancer AR42J del radiofarmaco {sup 99m}Tc-Tyr{sup 3}-Octreotido-dendrimero analogo de la somatostatina

    Orocio R, E.

    2013-07-01

    The objective of this project was preparing a multimeric system through the conjugation of several molecules of the peptide Tyr{sup 3}-Octreotide to a dendrimer molecule based on Poly-amidoamine (PAMAM), as well as radiolabeled with {sup 99m}Tc and evaluating its behavior like new radiopharmaceutical similar of somatostatin. The dendrimer PAMAM generation 3.5 that possesses terminal groups of sodium carboxylate, was functionalized to peptide Tyr{sup 3}-Octreotide through a reaction of peptide coupling with HATU (hexafluorophosphate (V) of 1-oxide-3-(bis(dimethylamino)methylene)-3H-[1,2,3]triazole[4,5-b]pyridine) as activating agent of carboxylate groups using the Size Exclusion Chromatography (Sec) as purification method. The product was characterized by Ultraviolet visible spectrophotometry, Mid-infrared and Far-infrared, Elemental analysis, Energy dispersive X-ray spectroscopy, Scanning electron microscopy, Thermogravimetry and Differential scanning calorimetry. The radiolabeled with {sup 99m}Tc was carried out using a direct method that involves the reduction of the anion TcO{sub 4}{sup -} with stannous chloride, so that the dendrimer is capable of coordinating to the technetium forming a chelate compound. The radiochemical purity of the radiolabeled compound was determined by thin layer chromatography using a sodium chloride solution to 20% (m/v) as mobile phase and was verified by molecular exclusion chromatography. The radiolabeled compound was possible to obtain it with a radiochemical purity superior to 90%. Also, the specific and not specific union was evaluated of the synthesized compound in mouse pancreas cancer cells AR42J, positive to somatostatin receptors, showing specific recognition for this receptors type with high cellular internalization. The biodistribution studies were carried out in BALB/c mice at different post injection times and in nude mice with induced tumors AR42J. The results showed that the {sup 99m}Tc-PAMAM-Tyr{sup 3}-Octreotide is excreted by via renal as hepatobiliary with a tumor capture of 4.12±0.6 D.I.g{sup -1} at the two hours of having been administered, which shows their potential as new radiopharmaceutical similar of somatostatin for the tumors detection of neuroendocrine origin. (Author)

  15. Application of PtSn/C catalysts and Nafion SiO{sub 2} membranes in direct ethanol fuel cell at high temperatures; Aplicacao de catalisadores PtSn/C e membranas Nafion SiO{sub 2} em celulas a combustivel de etanol direto em elevadas temperaturas

    Dresch, Mauro Andre

    2014-07-01

    This work has as objective to evaluate anodes and electrolytes in direct ethanol fuel cells (DEFC) operating at high temperature (130 deg C). As anode materials, electrocatalysts based on Pt Sn/C were prepared by Modified Polyol Method with various Pt:Sn atomic ratios. Such methodology promotes self organized electrocatalysts production with narrow particle size distribution and high alloying degree. The electrocatalysts were characterized by XRD, and CO stripping. The results showed that these materials presented high alloying degree and Eonset CO oxidation at lower potential as commercial materials. As electrolyte, Nafion-SiO{sub 2} hybrids were synthesized by sol-gel reaction, by the incorporation of oxide directly into the ionic aggregates of various kinds of Nafion membranes. The synthesis parameter, such sol-gel solvent, membrane thickness and silicon precursor concentration were studied in terms of silica incorporation degree and hybrid mechanical stability. Finally, the optimized anodes and electrolytes were evaluated in DEFC operating at 80 - 130 deg C temperature range. The results showed a significant improvement of the DEFC performance (122 mW cm{sup -2}), resulted from the acceleration of ethanol oxidation reaction rate due to anode material optimization and high temperature operation once the use of hybrids possibilities the increase of temperature without a significant conductivity loses. In this sense, the combination of optimized electrodes and electrolytes are a promising alternative for the development of these devices. (author)

  16. Use of phyllosilicates in electrochemical devices: possible use of sepiolite as a support of catalysts in direct alcohol fuel cells (DAFC); Utilizacao de filosilicatos em dispositivos eletroquimicos: possivel uso da sepiolita como suporte de catalisadores em celulas a combustivel com uso direto de etanol (DAFC)

    Parra-Silva, J.; Silva, A.C.; Mello-Castanho, S.R.H. [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Cerpa, A. [Universidad Europea de Madrid, Madrid (Spain)

    2014-07-01

    Direct alcohol Fuel cells (DAFC) are interesting to use Brazil for reasons of fuel logistics and availability. The catalysts used in these devices to promote the oxidation of alcohol at the anode need to be fixed on a substrate which must provide high specific surface area, porosity, chemical and thermal resistance, this target can be achieved with the characteristics sepiolite. This paper proposes sepiolite as catalyst support for DAFC. Sepiolite is a phyllosilicate with double layered tetrahedral silicon cells and fibrillar structure. Catalysts (Pt / Sb / Sn) were prepared by cation substitution method and tested by cyclic voltammetry. Techniques as XRD and FT-IR were also used for characterizing materials. Was obtained up to 35 mA / g (Pt) peak current (redox ethanol) indicating the possibility of sepiolite technology development to use un proposed purpose. (author)

  17. Study of the oxygen reduction reaction using Pt-Rare earths (La, Ce, Er) electrocatalysts for application of PEM fuel cells; Estudo da reacao de reducao do oxigenio utilizando eletrocatalisadores a base de Pt-terras raras (La, Ce, Er) para aplicacao em celulas a combustivel tipo PEM

    Gomes, Thiago Bueno

    2013-07-01

    The complexity of the oxygen reduction reaction (ORR) and its potential losses make it responsible for the most part of efficiency losses at the Fuel Cells. For this reaction the electrocatalyst witch is most appropriated and shows better performance is platinum, a noble metal that elevates the cost, raising barriers for Fuel Cells technology to enter the market. First this work focuses on reducing the amount of platinum used in the cathode, by being replaced by rare earths. The most common methods of synthesis involves a large amount of steps and this work proposed to prepare the electrocatalyst through a simpler way that would not take so many steps and time to be done. Using an ultrasound mixer the electrocatalyst was prepared mixing platinum supported on carbon black and the rare earths lanthanum, cerium and erbium oxides to be applied in a half-cell study of the ORR. The Koutecky-Levich plots shows that among the electrocatalysts prepared the Pt80Ce20/C had the catalytic activity close to the commercial BASF platinum on carbon black, suggesting that the reaction was taken by the 4-electron path. As found in some works in literature, among the rare earth used to study the ORR, cerium is the one witch shows the better performance because it is able to store and provide oxygen. This feature is of great interest for the ORR because this reaction is first order to the oxygen concentration. Results show that is possible to reduce the amount of platinum maintaining the same electrocatalyst activity. (author)

  18. Characterization of cathode materials SrCoO3 and La0,2Sr0,8CoO3 for use in solid oxide fuel cells (SOFC); Caracterizacao de materiais catodicos SrCoO3 e La0,2Sr0,8CoO3 para aplicacao em celulas a combustivel de oxido solido (SOFC)

    Galvao, G.O.; Aquino, F.M; Silva, R.M.; Medeiros, I.D.M. de, E-mail: gabriela.galvao@cear.ufpb.br [Universidade Federal da Paraiba (UFPB), Joao Pessoa, PB (Brazil)

    2016-07-01

    Mixed oxide ceramics with chemical structure of ABO{sub 3} type are promising candidates for cathodes of solid oxide fuel cells (SOFC) for performing well on the electrical conductivity and thermal stability. Various methods of preparation have been studied and used for the synthesis of these materials. In this study, SrCoO{sub 3} and La{sub 0,2}Sr{sub 0,8}CoO{sub 3} perovskites were synthesized using gelatin as directing agent with the purpose of producing homogeneous and porous particles. The powders obtained at 350 ° C / 2 h were calcined at 600, 800 and 1000 ° C for 4 hours and characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The results showed that gelatin is a good polymerizing agent for metal ions as the material showed characteristic peaks of perovskite, with good porosity and uniformity. Furthermore, the method of synthesis employed has advantages related to cost and toxicity, which are very low. (author)

  19. Development of a membrane electrode as assembly production process for proton exchange membrane fuel cell (PEMFC) by sieve printing; Desenvolvimento de processo de producao de conjuntos eletrodo-membrana-eletrodo para celulas a combustivel baseadas no uso de membrana polimerica conditora de protons (PEMFC) por impressa a tela

    Bonifacio, Rafael Nogueira

    2010-07-01

    Energy is a resource that presents historical trend of growth in demand. Projections indicate that future energy needs will require a massive use of hydrogen as fuel. The use of systems based on the use of proton exchange membrane fuel cell (PEMFC) has features that allow its application for stationary applications, automotive and portable power generation. The use of hydrogen as fuel for PEMFC has the advantage low pollutants' emission, when compared to fossil fuels. For the reactions in a PEMFC is necessary to build membrane electrode assembly (MEA). And the production of MEAs and its materials are relevant to the final cost of k W of power generated by systems of fuel cell. This represent currently a technological and financial barriers to large-scale application of this technology. In this work a process of MEAs fabrication were developed that showed high reproducibility, rapidity and low cost by sieve printing. The process of sieve printing and the ink composition as a precursor to the catalyst layer were developed, which allow the preparation of electrodes for MEAs fabrication with the implementation of the exact catalyst loading, 0.6 milligrams of platinum per square centimeters (mgPt.cm{sup -2}) suitable for cathodes and 0.4 mgPt.cm{sup -2} for anode in only one application step per electrode. The ink was developed, produced, characterized and used with similar characteristics to ink of sieve printing build for other applications. The MEAs produced had a performance of up to 712 m A.cm{sup -2} by 600 mV to 25 cm{sup 2} MEA area. The MEA cost production for MEAs of 247.86 cm{sup 2}, that can generate 1 kilowatt of energy was estimated to US$ 7,744.14 including cost of equipment, materials and labor. (author)

  20. Evaluation and application of PEMFC fuel cell's technologies developed at IPEN applied to a 500 W{sub e} fuel cell stack; Avaliacao e aplicacao de tecnologias de celulas a combustivel tipo PEMFC desenvolvida no IPEN em um modulo de 500 W{sub e} de potencia nominal

    Cunha, Edgar Ferrari da

    2009-07-01

    This work is part of a research project on PEMFC technologies carried out in IPEN to develop and optimize a 500 W{sub e} fuel cell stack. The MEAs scaling up from 25 cm{sup 2} to 144 cm{sup 2} produced by the method of sieve printing; computational fluid dynamics by computer simulation of gas flow channels in bipolar plates using COMSOL{sup R} program and the use of Pt/C electrodes developed by alcohol reduction method in single cells were used to build a stack of 500 W{sub e} nominal power for possible commercial applications, produced with national technology and industrial support. A 100 hours fuel cell's test was carried out in a 144 cm{sup 2} single cell to study the stability of the MEA fabricated by sieve printing method. This single cell showed good stability within this period of time. The developed stack has reached the maximum power of 574 W{sub e} at 100 A (694.4 mA cm{sup -2}). The operating power of 500 W{sub e} was obtained at 77.7 A (540.1 mA cm{sup -2}) and potential of 6.43 V, with efficiency of 43.3%. In terms of cogeneration, the thermal power or generated heat by the stack was 652 W{sub t}. The initial estimated cost for the 500 W{sub e} stack was about R$ 4,500.00, considering only the used materials for its construction. (author)

  1. Cultivation and irradiation of human fibroblasts in a medium enriched with platelet lysate for obtaining feeder layer in epidermal cell culture; Cultivo e irradiacao de fibroblastos humanos em meio enriquecido com lisado de plaquetas para obtencao de camada de sustentacao em culturas de celulas da epiderme

    Yoshito, Daniele

    2011-07-01

    For over 30 years, the use of culture medium, enriched with bovine serum, and murines fibroblasts, with the rate of proliferation controlled by irradiation or by share anticarcinogenic drugs, has been playing successfully its role in assisting in the development of keratinocytes in culture, for clinical purposes. However, currently there is a growing concern about the possibility of transmitting prions and animals viruses to transplanted patients. Taking into account this concern, the present work aims to cultivate human fibroblasts in a medium enriched with human platelets lysate and determine the irradiation dose of these cells, for obtaining feeder layer in epidermal cell culture. For carrying out the proposed objective, platelets lysis has standardized, this lysate was used for human fibroblasts cultivation and the irradiation dose enough to inhibit its duplication was evaluated. Human keratinocytes were cultivated in these feeder layers, in culture medium enriched with the lysate. With these results we conclude that the 10% platelets lysate promoted a better adhesion and proliferation of human fibroblasts and in all dose levels tested (60 to 300 Gy), these had their mitotic activity inactivated by ionizing irradiation, being that the feeder layers obtained with doses from 70 to 150 Gy were those that provided the best development of keratinocytes in medium containing 2.5% of human platelet lysate. Therefore, it was possible to standardize both the cultivation of human fibroblasts as its inactivation for use as feeder layer in culture of keratinocytes, so as to eliminate xenobiotics components. (author)

  2. Studies on the efficiency during reactivation of a generation system based on natural gas reformer and a 5 k W fuel cell; Estudos de eficiencia durante reativacao de um sistema de geracao baseado em reformador de gas natural e celula a combustivel de 5 kW

    Lopes, Francisco da Costa; Furtado, Jose Geraldo de Melo; Silva Junior, Fernando Rodrigues da; Serra, Eduardo Torres [Centro de Pesquisas de Energia Eletrica (CEPEL), Rio de Janeiro, RJ (Brazil)]. E-mail: fcl@cepel.br

    2008-07-01

    Fuel cell based power generation systems have been pointing as promising technology for stationary applications mainly to supply power to critical loads. Among several types of fuel cells the Polymer Electrolyte Membrane Fuel Cells (PEMFC) are the main type used around the world. Nowadays reformers are widely employed to produce hydrogen for fuel cells. The Fuel Cell Laboratory of CEPEL has a power plant based on a 5 kW PEMFC and a natural gas reformer. For a long time the PEMFC was inoperable due to reformer malfunctioning and during this time the full power availability of PEMFC was lost due to deactivation of its catalytic sites. In most cases this deactivation is reversible. So it was started a reactivation process aiming to recover the full operational condition of the PEMFC unit. During this process the gas flow relationship and efficiency of the reformer were studied. An analysis of the PEMFC reactivation was conducted where it was noted that the reactivation took place as expected. During the reactivation process the PEMFC and the whole system efficiency were analyzed. The results suggest that the PEMFC can reach efficiency compatible with conventional power generation systems thus allowing PEMFC technology to compete with these energy sources in point of efficiency. (author)

  3. Evaluation of umbilical cord mesenchymal stem cells labeling with superparamagnetic iron oxide nanoparticles coated with dextran and complexed with Poly-L-Lysine; Avaliacao da marcacao de celulas-tronco mesenquimais de cordao umbilical com nanoparticulas superparamagneticas de oxido de ferro recobertas com Dextran e complexadas a Poli-L-Lisina

    Sibov, Tatiana Tais; Mamani, Javier Bustamante; Pavon, Lorena Favaro; Cardenas, Walter Humberto; Gamarra, Lionel Fernel, E-mail: tatianats@einstein.br [Instituto do Cerebro - InCe, Hospital Israelita Albert Einstein - HIAE, Sao Paulo, SP (Brazil); Miyaki, Liza Aya Mabuchi [Faculdade de Enfermagem, Hospital Israelita Albert Einstein - HIAE, Sao Paulo, SP (Brazil); Marti, Luciana Cavalheiro; Sardinha, Luiz Roberto [Centro de Pesquisa Experimental, Hospital Israelita Albert Einstein - HIAE, Sao Paulo, SP (Brazil); Oliveira, Daniela Mara de [Universidade de Brasilia - UnB, Brasilia, DF (Brazil)

    2012-04-15

    Objective: The objective of this study was to evaluate the effect of the labeling of umbilical cord vein derived mesenchymal stem cells with superparamagnetic iron oxide nanoparticles coated with dextran and complexed to a non-viral transfector agent transfector poly-L-lysine. Methods: The labeling of mesenchymal stem cells was performed using the superparamagnetic iron oxide nanoparticles/dextran complexed and not complexed to poly-L-lysine. Superparamagnetic iron oxide nanoparticles/dextran was incubated with poly-L-lysine in an ultrasonic sonicator at 37 deg C for 10 minutes for complex formation superparamagnetic iron oxide nanoparticles/dextran/poly-L-lysine by electrostatic interaction. Then, the mesenchymal stem cells were incubated overnight with the complex superparamagnetic iron oxide nanoparticles/dextran/poly-L-lysine and superparamagnetic iron oxide nanoparticles/dextran. After the incubation period the mesenchymal stem cells were evaluated by internalization of the complex superparamagnetic iron oxide nanoparticles/dextran/polyL-lysine and superparamagnetic iron oxide nanoparticles/dextran by Prussian Blue stain. Cellular viability of labeled mesenchymal stem cells was evaluated by cellular proliferation assay using 5,6-carboxyfluorescein-succinimidyl ester method and apoptosis detection by Annexin V- Propidium Iodide assay. Results: mesenchymal stem cells labeled with superparamagnetic iron oxide nanoparticles/ dextran without poly-L-lysine not internalized efficiently the superparamagnetic iron oxide nanoparticles due to its low presence detected within cells. Mesenchymal stem cells labeled with the complex superparamagnetic iron oxide nanoparticles/dextran/polyL-lysine efficiently internalized the superparamagnetic iron oxide nanoparticles due to greater presence in the cells interior. The viability and apoptosis assays demonstrated that the mesenchymal stem cells labeled and not labeled respectively with the superparamagnetic iron oxide nanoparticles/dextran/poly-L-lysine continue to proliferate over seven days and the percentage of cells in early or late apoptosis is low compared to the percentage of live cells over the three days. Conclusion: Our results showed that the use of poly-L-lysine complexed with superparamagnetic iron oxide nanoparticles/dextran provides better internalization of these superparamagnetic iron oxide nanoparticles in mesenchymal stem cells Thus, we demonstrated that this type of labeling is not cytotoxic to the mesenchymal stem cells, since the viability and apoptosis assays showed that the cells remain alive and proliferating. The efficiency of this type of labeling in mesenchymal stem cells can provide non-invasive methods for monitoring these cells in vivo. (author)

  4. Modifier action of the chlorophyllin of the mutagenesis induced by the ethyl-nitroso-urea (ENU) in germinal cells of Drosophila melanogaster; Accion modificadora de la clorofilina de la mutagenesis inducida por la etil-nitroso-urea (ENU) en celulas germinales de Drosophila melanogaster

    Morales N, I

    2006-07-01

    The cupro-sodium chlorophyllin (CCS) it is a soluble porphyrin in water that it includes in its it structures a copper atom instead of the magnesium that has the chlorophyll. Diverse experiments have demonstrated that it possesses a potent activity, reducing or inhibiting, the DNA damage caused by physical and chemical agents of direct action or insinuation. Most of the knowledge about their anti genotoxic activity has been obtained using somatic cells of different organisms, on the other hand it is known very little of their effect in germinal cells. At the moment in the Drosophila laboratory of the ININ it is investigating the protective action of the CCS in germinal cells, with these studies has been observed that its administration to females that were crossed with males irradiated with 20 Gy of gamma radiation, promotes the induction of lethal dominant in the embryonic and post-embryonic states causing a diminution in the viability egg-adult. With the test of lethal recessive bound to the sex one has evidence that it increases the basal frequency of lethal recessive and it doesn't reduce those induced by radiation. In contrast, with the present investigation when the CCS was administered to males that later on were treated with ethyl-nitroso-urea (ENU) caused a reduction of the lethal frequency in all the monitored cellular states, but only it was significant in the post-meiotic cells. On the contrary, when the CCS was administered to the female ones and then they crossed with males treaties with ENU, it was observed a tendency to increase the lethal ones in all the cellular types. With both protocols the CCS caused a diminution of the sterility. The fact that the CCS has antagonistic activities, it deserves special attention to investigate with different protocols and systems, the conditions in that this pigment can work as a true antimutagenic and/or anti carcinogenic before being able to him to propose as a chemopreventor. (Author)

  5. {beta} -carotene effect the induction of the sister chromatid exchanges (ICH) by gamma radiation in mouse radiosensibilized osseous marrow cells In vivo; Efecto del {beta}- caroteno la induccion de intercambios en las cromatidas hermanas (ICH) por radiacion gamma en celulas radiosensibilizadas de la medula osea de raton In vivo

    Morales R, P.; Cruz V, V.L. [Instituto Nacional de Investigaciones Nucleares, A.P. 18-1027, 11801 Mexico D.F. (Mexico). Dept. de Biologia

    1997-07-01

    The effect of {beta}- carotene over the ICH radioinduction in radiosensibilized with BrdU osseous marrow cells of mouse was determined In vivo. The treatment with 50 {mu}g {beta} carotene per se induces a significant increment in the ICH frequency and the pre or post-treatment with the same dose causes an additive effect in the ICH frequency produced by 0.62 Gy of gamma radiation. This implies that {beta}- carotene does not have radioprotective activity, under conditions which was developed this experiment. (Author)

  6. Comparative analysis between two systems to generate electric energy for isolated community in the interior of the Amazon state: fuel cells with natural gas reformer versus diesel generation; Analise comparativa entre dois sistemas de geracao de energia eletrica para a comunidade isolada no interior do estado do Amazonas: celula a combustivel com reformador para gas natural versus gerador diesel

    Araujo, Paula Duarte; Bergamini, Cristiane Peres; Camargo, Joao Carlos; Lopes, Daniel Gabriel [Universidade Estadual de Campinas (UNICAMP), Campinas, SP (Brazil). Fac. de Engenharia Mecanica; Esteves, Gheisa Roberta Telles [Universidade Estadual de Campinas (UNICAMP), Campinas, SP (Brazil). Nucleo de Pesquisas e Estudos Ambientais; Silva, Ennio Peres da Silva [Universidade Estadual de Campinas (UNICAMP), Campinas, SP (Brazil). Inst. de Fisica Gleb Wataghin

    2004-07-01

    Although great part of the domestic territory is already supplied with electric energy, still there are many regions where the system is precarious or nonexistent, generically called isolated communities. In the majority of the cases these communities are supplied with Diesel oil generators and the substitution of this fuel for available alternative energy in the localities has been object of study of some institutions of research spread throughout the country. Currently, the use of fuel cells has been strongly argued in the generation of electric energy associated with the local energy necessity, from the use of a regional fuel and this is due to the high efficiency of allied energy conversion to the low ambient impacts that this equipment offers. Most of the different types of fuel cells use hydrogen as a fuel to produce electricity, and it is extracted from renewable or non-renewable sources of energy. Then, the article has the objective of comparing in first analysis the energy efficiency and the cost between the two systems: the ones used currently in the great majority of the isolated communities, constituted of a Diesel engine-generator system, with Natural Gas Reformer System/ Purifier of Hydrogen/ Fuel Cell/ and to analyze if such project presents characteristics that qualifies it to get the carbon credits proposed in the Mechanism of Clean Development. (author)

  7. Preparation and characterization of PVA/SSA membranes with Al{sub 2}O{sub 3} nanoparticles for fuel cell applications; Preparacao de caracterizacao de membranas de PVAL/SSA na presenca de nanoparticulas de Al{sub 2}O{sub 3} para aplicacao em celulas de combustivel

    Oliveira, Paula N.; Pires, Alfredo T.N. [Grupo de Estudo em Materiais Polimericos - POLIMAT - UFSC, Florianopolis, SC (Brazil); Catarino, Margarida; Brandao, Lucia; Tanaka, Alfredo; Mendes, Adelio [Faculdade de Engenharia da Universidade do Porto, Porto (Portugal)

    2011-07-01

    In the present study, PVA/SSA membranes were prepared with and without the addition of Al{sub 2}O{sub 3} nanoparticles. Sulfosuccinic acid (SSA) was used as the crosslinking agent. Membranes were prepared with different amounts of SSA (26, 43 and 55 wt.%) and with 5 and 10 wt.% of nanoparticles. Crosslinking was performed at 90 degree C during 1.5 h. Membranes were analyzed by infrared spectroscopy, thermal analysis, water absorption, ion exchange capacity (IEC) and proton conductivity. The results showed that control of the crosslinking conditions, IEC value, water absorption and polymer structure are of significant importance to obtain a set of properties suitable for application in proton exchange membrane fuel cells. (author)

  8. Induction of genetic recombination in the lambda bacteriophage by ultraviolet irradiation of the Escherichia Coli cells. III. Role of the ruvA and recN genes; Induccion de recombinacion genetica en el bacteriofago lambda por irradiacion ultravioleta de las celulas de Escherichia Coli. III. Papel de los genes ruvA and recN

    Alcantara D, D [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico)

    1987-05-15

    The objective of this work is to determine the paper of the genes ruvA and recN in the stimulation of the recombination of Lambda for UV irradiation of Escherichia Coli, taking into account that both genes are inducible, they belong to the group of genes that participate in the SOS response and that a deficiency in its expression reduces the capacity to repair and recombiner the DNA. (Author)

  9. Electrolytic hydrogen production at off-peak consumption and his utilization as energy vector at peak consumption through use of fuel cells; Producao de hidrogenio eletrolitico nos horarios fora de ponta e sua utilizacao como vetor energetico nos horarios de ponta atraves do uso de celulas a combustivel

    Gambetta, Francielle [Universidade Estadual de Campinas (UNICAMP), SP (Brazil). Faculdade de Engenharia Mecanica. Dept. de Energia]. E-mail: fgambetta@fem.unicamp.br; Silva, Ennio Peres da [Universidade Estadual de Campinas (UNICAMP), SP (Brazil). Inst. de Fisica. Lab. de Hidrogenio

    2008-07-01

    Due the fact that consumers have different demand, depending on the pace of economic activities and their daily habits of consumption, there is a different electrical demand throughout the day. Demand, in general, is minimal during the morning and it grows with the move for hours to reach peak consumption between 18:00 and 22:00, then turning to fall. It is old the idea of storing electricity produced in off-peak for its consumption in peak hours. To store large amounts of electrical power is required its conversion into some other form of energy, since it is impossible to store electrical energy as such in large quantities. One way of storing electricity is in the form of hydrogen produced by electrolysis of water which then can be stored, purified and converted into electricity through fuel cells. When there is an increase in demand for electricity, there is a need to expand the supply of energy, which means investments in generation, transmission and distribution. This work was performed a preliminary analysis of the production of electrolytic hydrogen in hours of low demand and its use in the generation of electricity in peak hours, making use of the fuel cells, so that to a certain limit value of increased electricity demand, there is no need for expansion of supply of Foz do Iguacu/PR. Moreover, at this work, the ability to harness the heat generated in fuel cells for heating water in homes was considered. (author)

  10. Evaluation and application of PEMFC fuel cell's technologies developed at IPEN applied to a 500 W{sub e} fuel cell stack; Avaliacao e aplicacao de tecnologias de celulas a combustivel tipo PEMFC desenvolvida no IPEN em um modulo de 500 W{sub e} de potencia nominal

    Cunha, Edgar Ferrari da

    2009-07-01

    This work is part of a research project on PEMFC technologies carried out in IPEN to develop and optimize a 500 W{sub e} fuel cell stack. The MEAs scaling up from 25 cm{sup 2} to 144 cm{sup 2} produced by the method of sieve printing; computational fluid dynamics by computer simulation of gas flow channels in bipolar plates using COMSOL{sup R} program and the use of Pt/C electrodes developed by alcohol reduction method in single cells were used to build a stack of 500 W{sub e} nominal power for possible commercial applications, produced with national technology and industrial support. A 100 hours fuel cell's test was carried out in a 144 cm{sup 2} single cell to study the stability of the MEA fabricated by sieve printing method. This single cell showed good stability within this period of time. The developed stack has reached the maximum power of 574 W{sub e} at 100 A (694.4 mA cm{sup -2}). The operating power of 500 W{sub e} was obtained at 77.7 A (540.1 mA cm{sup -2}) and potential of 6.43 V, with efficiency of 43.3%. In terms of cogeneration, the thermal power or generated heat by the stack was 652 W{sub t}. The initial estimated cost for the 500 W{sub e} stack was about R$ 4,500.00, considering only the used materials for its construction. (author)

  11. Analysis for impedance electrochemistry 'on-line' of membrane/electrode assemble (MEA) of protons exchange membrane fuel cells (PEMFC); Analise por impedancia eletroquimica 'on-line' de conjuntos eletrodos/membrana (MEA) de celulas a combustivel a membrana polimetrica (PEMFC)

    Santos, Antonio Rodolfo dos

    2007-07-01

    This work reports results of studies and characterization on membrane electrode assemblies (MEAs) for proton exchange membrane fuel cell (PEMFC). Some cell operation conditions and different processes of MEA production were investigated. The electrochemical impedance spectroscopy technique (EIS) (in situ - 0 to 16 A) was used 'on-line' as a tool for diagnosis, concerning the cell performance. The EIS measurements were carried out with a FC350 Fuel Cell EIS System (GAMRY), coupled to a PC4 potentiostat/galvanostat and connected to the electronic load (TDI) for 'on-line' EIS experiments (100 mHz - 10 kHz, dU = 5 mV). MEAs with 25 cm{sup 2} surface area, using PtM/C 20% (M Ru, Sn or Ni) electrocatalysts were manufactured using the alcohol reduction process (ARP). The catalytic ink was applied directly into the carbon cloth (GDL) and pressed in the Nafion membrane (105). MEAs using Pt/C and Pt Ru/C 20% from E-TEK electrocatalysts were manufactured by comparison. All the cathodes were sprayed with Pt/C 20% from E-TEK. The noble metal concentrations used were set to 0.4 mg Pt.cm{sup -2} at the anode and 0.6 mg Pt.cm{sup -2} at the cathode (E-TEK). Nyquist diagrams of the MEAs with Pt/C and PtRu/C from E-TEK or PtM/C (M = Ru, Sn or Ni) ARP showed essentially the same ohmic resistances for the MEAs. This fact can be explained by suppression of agglomerates during the MEA preparation process or by the homogeneity of the anchored electrocatalysts at the carbon surface. It could also be observed, at low current densities, that there was a significant performance difference between the electrocatalysts from E-TEK and those prepared with the alcohol reduction process. The polarization curves results confirmed that the Pt M/C (M = Ru, Sn or Ni) ARP showed an activity increase for the methanol and ethanol fed cells. The technique of EIE was shown efficient for the evaluation of the method preparation of MEAs and the acting of the cell, the results of EIE showed coherence in the choice of the model the electric circuit for MEAs using hydrogen, methanol and ethanol. This coherence indicates that other resistances no considered in the model are not relevant in the total resistance of MEAs. (author)

  12. Preparation and characterization of Nafion - TiO{sub 2} composite electrolytes for application in proton exchange membrane fuel cells; Preparacao e caracterizacao de eletrolitos compositos Nafion - TiO{sub 2} para aplicacao em celulas a combustivel de membrana de troca protonica

    Matos, Bruno Ribeiro de

    2008-11-06

    The fabrication and characterization of Nafion - TiO{sub 2} composites, and the use of such electrolytes in PEM (Proton Exchange Membrane) fuel cell operating at high temperature (130 deg C) were studied. The operation of a PEM fuel cell at such high temperature is considered as an effective way to promote fast electrode reaction kinetics, high diffusional transport, and high tolerance to the carbon monoxide fuel contaminant. The polymer Nafion{sup R} is the most used electrolyte in PEM fuel cells due to its high proton conductivity. However, the proton transport in Nafion is dependent on the water content in the polymeric membrane. The need of absorbed water in the polymer structure limits the operation of the fuel cell to temperatures close to 100 deg C, above which Nafion exhibits a fast decrease of the ionic conductivity. In order to increase the performance of the electrolyte operating at high temperatures, Nafion-TiO{sub 2} composites have been prepared by casting. The addition of titania hygroscopic particles to the polymeric matrix aims at the enhancement of the humidification of the electrolyte at temperatures above 100 deg C. Three types of titania particles with different specific surface area and morphology have been investigated. Nafion-based composites with the addition of titania nanoparticles, in the 2.5-15 wt.% range, with nearly spherical shape and specific surface area up to approx. 115 m{sup 2}g{sup -1} were found to have higher glass transition temperature than the polymer. Such an increase improves the stability of the electrolyte during the fuel cell operation at high temperatures. The addition of titania-derived nanotubes results in a pronounced increase of the performance of PEM fuel cell operating at 130 deg C. In this composite, the high specific surface area and the tubular shape of the inorganic phase are responsible for the measured increase of both the absorption and retention of water of the composite electrolyte. Nonetheless, the polarization curves of fuel cell using the composite electrolytes exhibited an increase of the ohmic polarization associated with the addition of the insulating titania particles. As the chemical structure of Nafion was observed to be insensitive to the addition of the inorganic particles, the high performance of the composite electrolytes is a result of competing effects: the decrease of the electrical conductivity and a higher thermal stability or water absorption/retention capacity. The experimental results suggest that the Nafion-TiO{sub 2} composites are promising electrolytes for PEM fuel cells operating at temperatures above approx. 100 deg C. (author)

  13. Content and chemical composition of Hyptis marrubioides essential oil in function of seasons

    Botrel, Priscila Pereira; Pinto, José Eduardo Brasil Pereira; Ferraz, Vany; Bertolucci, Suzan Kelly Vilela; Figueiredo, Felipe Campos

    2010-01-01

    Os oleos essenciais sao principios odoriferos armazenados em celulas especiais da planta. O oleo essencial no genero Hyptis e usado como anestesico, antiespasmodico, antiinflamatorio e pode induzir aborto em doses elevadas. O objetivo deste trabalho foi avaliar a influencia da sazonalidade no teor e composicao do oleo essencial de Hyptis marrubioides. O delineamento experimental foi inteiramente casualizado, com quatro tratamentos (inverno, primavera, verao e outono) e seis repeticoes, totali...

  14. Study of apoptotic mechanisms induced by all-trans retinoic acid and its 13-cis isomer on cellular lines of human hepato carcinoma Hep3B and HepG2; Estudio de los mecanismos apoptoticos inducidos por el acido retinoico todo-trans y su isomero 13-cis en las lineas celulares de hepatocarcinoma humano Hep3B y HepG2

    Arce Vargas, Frederick [Costa Rica

    2006-07-01

    of these cells to different chemotherapeutic agents. Survivin might decrease the answer of treatment by to be anti-apoptotic and even to change the apoptosis by other forms of cellular death (necrosis, mitotic catastrophe, etc.) doing that therapy be less efficient. Hep3B cells were sensitized with ATRA before to be treated with 5-FU and it was observed a more cytotoxicity than when every drug was used separately. Also there were required concentrations lower of both agents to produce cellular death. This effect didn't see with HepG2 cells. Although retinoids seem to be promising in the hepato carcinoma treatment, it must do more studies to improve the bioavailability and to decrease the unspecific toxicity of these drugs, including combinations with other agents, use of liposomes or synthesis of compounds with effects more selective that might be even directed to certain specific routes of cellular death. (author) [Spanish] Dos lineas celulares de cancer de higado (Hep3B and HepG2) se incubaron durante diferentes periodos de tiempo con varias concentraciones de dos isomeros del acido retinoico (ATRA y 13-cis AR) y con los agentes quimioterapeuticos 5-FU, cisplatino y paclitaxel. Se determino si estas sustancias inducian citotoxicidad, apoptosis y si modificaban la expresion de diferentes genes relacionados con la muerte celular por apoptosis, en parte para poder explicar la resistencia del carcinoma hepatocelular a estas drogas. Las celulas HepG2 mostraron mayor resistencia que las celulas Hep3B a las 72 horas de tratamiento, tanto el ATRA como el 13-cis AR fueron toxicos. Tambien se demostro que producian apoptosis en las dos lineas celulares. Este tipo de muerte celular parece estar mediada por una disminucion en la concentracion de Bcl-xL en las celulas Hep3B tratadas con ambos retinoides y un aumento en la concentracion de Bax en las celulas HepG2 tratadas con 13-cis AR. Se observo proteolisis de procaspasas 3 y 8 en las celulas Hep3B, sugiriendo activacion de

  15. Transplante de células tronco hematopoéticas para doenças auto-imunes no Brasil

    Voltarelli,Júlio C.

    2002-01-01

    O transplante de células progenitoras hematopoéticas apresenta bases sólidas para ser indicado no tratamento das doenças autoimunes. No relato são apresentados estes dados e a seqüência de eventos que tem contribuído para a implantação de um protocolo brasileiro do procedimento na modalidade autogênica utilizando regimes de mobilização uniforme com Ciclofosfamida 2g/m2 mais fator estimulador de colônias granulocitárias e condicionamentos particulares para o lúpus eritematoso sistêmico, escler...

  16. El historiador Fernández de Piedrahita

    Carlos López Narváez

    1964-10-01

    Full Text Available Varón de Dios, las letras y la patria, Lucas Fernández de Piedrahita nació en Santafé de Bogotá, el 6 de marzo de 1624, de hidalgo linaje por su padre español, y de principesca sangre materna, como que su progenitora, doña Catalina Collantes, esposa de don Domingo Fernández de Soto y Piedrahita, era nieta de doña Francisca Coya de la realeza inca del Perú.

  17. Mejor predictor lineal e insesgado familiar de aptitud combinatoria general en experimentos parciales de cruzas dialélicas con efectos maternos

    Montesinos-López, Osval Antonio; Mastache-Agunas, Ángel Agustín; Luna-Spinoza, Ignacio; Hernández-Suárez, Carlos Moisés; Hernández-Lira, Guadalupe

    2009-01-01

    En el mejoramiento genético de plantas y animales se han utilizado los experimentos de cruzas dialélicas (diseños completos de Griffing) para realizar estimaciones de parámetros y pruebas de hipótesis, lo cual es importante para la toma de decisiones en programas de mejoramiento genético. Los esquemas completos de Griffing son útiles cuando el número de líneas progenitoras es pequeño, sin embargo, cuando este número es elevado es difícil preparar, establecer y conducir los trabajos de campo. ...

  18. Ecuaciones diferenciales : teoría y práctica

    Perelló, Miguel Ángel

    2002-01-01

    Ecuaciones diferenciales de primer orden. Ecuaciones y sistemas de orden superior. Series y transformada de Laplace. Teoría de la estabilidad. Ecuaciones en derivadas parciales. Introducción al cálculo variacional.

  19. En Torno a la Estructura Social de los Mapuches Prehispánicos

    Osvaldo Silva

    Full Text Available La etnía mapuche estaba constituida por varias tribus, esparcidas sobre un amplio territorio, presentando algunas variantes culturales derivadas de su adaptación a medios ecológicos dislmiles.

  20. Synthesis and characterization of the perovskite Sm{sub 0.5}Sr{sub 0.5}CoO{sub 3} for using as cathode in solid oxide fuel cells; Sintese e caracterizacao da provsquita Sm{sub 0.5}Sr{sub 0.5}CoO{sub 3} para utilizacao como catodo em celulas a combustivel de oxido solido

    Blanco, P.H.L.; Muccillo, R.; Muccillo, E.N.S. [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)], e-mail: enavarro@usp.br

    2008-07-01

    Solid oxide fuel cells are basically constituted by ceramic materials, a solid electrolyte sandwiched between two electrodes. A number of ceramic materials with perovskite structure have been proposed to act as electrode material due to the combination of their physical and chemical properties along with compatibility with the solid electrolyte. In this work the mixed oxide Sm{sub 0,5}Sr{sub 0,5}CoO{sub 3} was synthesized by the cation complexation technique. This perovskite oxide has been proposed as cathode in solid oxide fuel cells that operates in the intermediate temperature range ({approx} 500 to {approx} 700 deg C). Citric acid was used as complexant agent. The thermal decomposition of the precursor material occurs in several stages up to 600 deg C. After calcinations at 700 deg C the mixed oxide exhibits the characteristic perovskite phase of Sm{sub 0,5} Sr{sub 0,5}CoO{sub 3} the microstructure of the thermally decomposed material consists of porous agglomerates. This technique allowed for obtaining a single phase material at a relatively lower temperature. (author)

  1. Preparation of PtSn/C, PtRu/C, PtRh/C, PtRuRh/C and PtSnRh/C electrocatalysts using an alcohol-reduction process for methanol and ethanol oxidation; Preparacao e caracterizacao de eletrocatalisadores PtRu, PtSn, PtRh, PtRuRh e PtSnRh para oxidacao direta de alcoois em celulas a combustivel tipo PEM utilizando a metodologia da reducao por alcool

    Dias, Ricardo Rodrigues

    2009-07-01

    In this work, Pt/C, PtRh (90:10), PtRh/C (50:50), PtSn/C (50:50), PtRu (50:50)/C, PtRuRh/C (50:40:10) and PtSnRh/C (50:40:10) were prepared by an alcohol-reduction process with metal loading of 20 wt.% using H{sub 2}PtCl{sub 6}.6H{sub 2}O (Aldrich), SnCl{sub 2}.2H{sub 2}O (Aldrich),and RhCl{sub 2}.XH{sub 2}O (Aldrich) as metals sources and Vulcan XC72 as support. The electrocatalysts were characterized by EDX, XRD and cyclic voltammetry (CV). The electro-oxidation of ethanol was studied by CV, chronoamperomety at room temperature in acid medium and tests at 100 deg C on a single cell of a direct methanol or ethanol fuel cell. The EDX analysis showed that the metal atomic ratios of the obtained electrocatalysts were similar to the nominal atomic ratios used in the preparation. The diffractograms of electrocatalysts prepared showed four peaks at approximately 2{theta} =40 deg, 47 deg, 67 deg and 82 deg, which are associated with the (111), (200), (220) and (311) planes, respectively, of a face cubic-centered (fcc) structure characteristic of platinum and platinum alloys. The average crystallite sizes using the Scherrer equation and the calculated values were in the range of 2-3 nm. For Pt Sn/C and PtSnRh/C two additional peaks were observed at 2 = 34 deg and 52 deg that were identified as a SnO{sub 2} phase. Pt Sn/C (50:50) and PtSnRh/C (50:40:10) electro catalyst showed the best performance for ethanol oxidation at room temperature. For methanol oxidation at room temperature Pt Ru/C, Pt Sn/C and PtRuRh/C electrocatalysts showed the best performance. Tests at 100 deg C on a single cell of a direct ethanol fuel cell PtSnRh/C showed the best performance, for methanol oxidation PtRuRh/C showed the best performance. (author)

  2. Preparation of PtSn/C, PtRu/C, PtRh/C, PtRuRh/C and PtSnRh/C electrocatalysts using an alcohol-reduction process for methanol and ethanol oxidation; Preparacao e caracterizacao de eletrocatalisadores PtRu, PtSn, PtRh, PtRuRh e PtSnRh para oxidacao direta de alcoois em celulas a combustivel tipo PEM utilizando a metodologia da reducao por alcool

    Dias, Ricardo Rodrigues

    2009-07-01

    In this work, Pt/C, PtRh (90:10), PtRh/C (50:50), PtSn/C (50:50), PtRu (50:50)/C, PtRuRh/C (50:40:10) and PtSnRh/C (50:40:10) were prepared by an alcohol-reduction process with metal loading of 20 wt.% using H{sub 2}PtCl{sub 6}.6H{sub 2}O (Aldrich), SnCl{sub 2}.2H{sub 2}O (Aldrich),and RhCl{sub 2}.XH{sub 2}O (Aldrich) as metals sources and Vulcan XC72 as support. The electrocatalysts were characterized by EDX, XRD and cyclic voltammetry (CV). The electro-oxidation of ethanol was studied by CV, chronoamperomety at room temperature in acid medium and tests at 100 deg C on a single cell of a direct methanol or ethanol fuel cell. The EDX analysis showed that the metal atomic ratios of the obtained electrocatalysts were similar to the nominal atomic ratios used in the preparation. The diffractograms of electrocatalysts prepared showed four peaks at approximately 2θ = 40{sup 0}, 47{sup 0}, 67{sup 0} and 82{sup 0}, which are associated with the (111), (200), (220) and (311) planes, respectively, of a face cubic-centered (fcc) structure characteristic of platinum and platinum alloys. The average crystallite sizes using the Scherrer equation and the calculated values were in the range of 2–3 nm. For PtSn/C and PtSnRh/C two additional peaks were observed at 2θ = 34{sup 0} and 52{sup 0} that were identified as a SnO{sub 2} phase. PtSn/C (50:50) and PtSnRh/C (50:40:10) electrocatalyst showed the best performance for ethanol oxidation at room temperature. For methanol oxidation at room temperature PtRu/C, PtSn/C and PtRuRh/C electrocatalysts showed the best performance. Tests at 100 deg C on a single cell of a direct ethanol fuel cell PtSnRh/C showed the best performance, for methanol oxidation PtRuRh/C showed the best performance. (author)

  3. Evaluation of the radiosensitizing to treatment with {sup 153}Sm-EDTMP, of haematopoietic cells of the bone marrow by means of bromodeoxyuridine incorporation into DNA, in a murine model; Evaluacion de la radiosensibilizacion al tratamiento con {sup 153}Sm-EDTMP, de las celulas hemotopoyeticas de la medula osea mediante la incorporacion de bromodesoxiuridina (BrdU) en el ADN, en un modelo murino

    Morales A, E.

    2008-07-01

    Bromodeoxyuridine (BrdU) has been shown to have a radiosensitizing effect, and its incorporation into DNA prior to administration of a bone-seeking radiopharmaceutical could increase the efficiency of bone marrow ablation, and even increase the specificity of radiation exposure for therapeutic purposes. The aim of the present study was to determine the effect of BrdU incorporation into DNA on the genotoxic and cytotoxic effects of samarium-153 ethylenediaminetetra-methylene phosphonate ({sup 153}Sm-EDTMP) in murine bone marrow cells. BALB/c male mice (N = 5 in each experiment) were treated with one of the following substances: a) BrdU (0.25 mg/g) b) {sup 153}-EDTMP (11.5 +- 3 MBq) c) BrdU (0.25 mg/g) plus {sup 153}Sm-EDTMP (11.5 +- MBq), there was also an untreated control. Cytotoxicity and genotoxicity were established by time-response and absorbed dose-response curves of polychromatic erythrocyte (PCE) and micro nucleated polychromatic erythrocyte (MN-PCE) frequencies, respectively, in murine peripheral blood samples in vivo. The significance of the differences between groups was determined by a variation of Dunett test for multiple groups and different-sized groups of a student test. Beta-absorbed dose fractions obtained from MNCP4B Monte Carlo computer code were used for mice bone marrow dosimetry calculations. At an average radiation absorbed dose of 0.38 Gy, 0.56 Gy and 0.82 Gy at 24, 40 and 72 h respectively, cells from animals treated with {sup 153}Sm-EDTMP showed a clear and significant induction of MN-PCE after 24 h, with the maximum response at 40 h, however, cells from group treated with BrdU plus {sup 153}Sm-EDTMP paradoxically showed MN-PCE frequencies only slightly higher than the control at the same absorbed dose. Treatment with {sup 153}Sm-EDTMP caused a slight reduction in PCE frequency, but exposure to BrdU or BrdU plus {sup 153}Sm-EDTMP induced a substantial and significant reduction in PCE frequency from 32 h to the end of the experiment (72 h). The PCE frequencies in the BrdU pretreated and irradiated group were consistently lower than in the BrdU control group, and the difference was significant at the final scored times in the experiment. These effects could be explained by lethal lesions of the accumulation of sublethal damage induced by the irradiation of BrdU-substituted DNA, where this lesion is not easily repaired and subsequently does not permit cell division or micronucleus formation. This research shows the increasing of cytotoxicity when BrdU was administered before the {sup 153}Sm-EDTMP treatment. Further studies are required in order to explore the utility of this strategy for bone marrow ablation or therapy in humans. (Author)

  4. Repairability during G1 of the inductor leisure of exchanges in the sister chromatid induced by alkylating agents in DNA substituted and no substituted with BUDR, in cells of the salivary gland of mouse In vivo; Reparabilidad durante G1 de las lesiones inductoras de intercambios en las cromatidas hermanas inducidos por agentes alquilantes en ADN sustituido y no sustituido con BrdU, en celulas de la glandula salival de raton In vivo

    Gonzalez B, F

    2004-07-01

    In this work you determines the repair of the lesions inductoras of Sister chromatid exchange (ICHs) generated in the cells of the salivary gland of mouse, for the treatment with the N-Methyl-N-Nitrosourea (MNU), the N-Ethyl-N-Nitrosourea (ENU), the Methyl methanesulfonate (MMS) and the Ethyl methanesulfonate (EMS) in early and slow G1 of the first one and the second cellular division, that is to say before and after the cells incorporate 5-bromine-2 -Desoxyuridine (BrdU) in the DNA. Groups witness non treaties were included with mutagen. The cells of the salivary gland repaired the generated lesions partially by the MNU, the MMS and the EMS in the 1st division, and only the lesions induced by the ENU and MMS were repaired partially in the 2nd division. The ENU generates injure that they were not repaired in the 1st division and those taken place by the EMS were little repaired in the 2nd division. The methylating agents generated but ICHs that the ethylating. One observes that the BrdU makes to the molecule of the DNA but susceptible to the damage generated by the alkylating agents that induce the formation of the ICHs. This susceptibility was incremented around 150% for the treatment with the MNU, the ENU and the MMS, on the other hand for the EMS it was 3 times minor. It is proposed that the one electronegative atom of this analog of the timine would to work as a nucleophyllic center with which the electrophyllic compounds react. (Author)

  5. Cytogenetic and dosimetric effects of {sup 131}I in lymphocyte of patients with differentiated thyroid cancer with and without r-hTSH stimulation. Study in thyroid tumor cells (WRO) treated with {sup 131}I and {sup 60}Co in vitro; Efeitos citogenetico e dosimetrico do {sup 131}I em pacientes com cancer diferenciado da tireoide com e sem estimulacao com r-hTSH. Estudo em celulas tumorais tireoidianas (WRO) tratadas com {sup 131}I e {sup 60}Co in vitro

    Valgode, Flavia Gomes Silva

    2015-11-01

    Differentiated thyroid cancer (DTC) represents about 90% of thyroid malignancies with increasing incidence in the recent decades. Treatment modalities include thyroidectomy, {sup 131}I therapy (with or without r-hTSH), radio and chemotherapy. Little is known about the effects of these treatments at the cellular level. This work was proposed in order to assess to what extent radioiodine therapy can cause damage in peripheral lymphocytes of patients with DTC, preceded or not by r-hTSH, taking into account acute, slow and dosimetric effects of {sup 131}I (in vivo study). An in vitro study was also carried out on thyroid tumor target cells (WRO) by cytotoxicity and genotoxicity analysis and radioiodine uptake. For this, blood samples from patients divided into two groups (group A, r-hTSH + {sup 131}I and group B,{sup 131}I only) were collected before, 24 hours, 1 week, 1 month and 1 year after {sup 131}I administration for aberration chromosome analysis (CA). A dose-response curve for {sup 131}I in vitro was developed for estimating the absorbed dose in patients, comparing the dicentric frequencies obtained in vitro with in vivo data by Monte Carlo program. Radioiodine therapy induced an increase in the number of CA in lymphocytes of patients peaking 24 hours after treatment, with gradual decline over time and with more chromosomal damage in group B than in group A, reaching baseline levels one year after radioiodine administration. The frequency of dicentric found inpatient lymphocytes, 24h after treatment, was equivalent to that induced in vitro (0.354 ± 0.153 MBq / mL for group A and 0.309 ± 0.154 MBq / mL for group B), which corresponds to absorbed doses of 0.8 ± 0.3 Gy and 0.7 ± 0.3 Gy for groups A and B, respectively, with no significant difference between the groups. WRO cells showed a cell cycle relatively slow: 96,3h with an unstable karyotype. The genotoxic test showed a relatively high radioresistance (0.07 to 3.70 MBq/mL), with no statistical significance, with or without r-hTSH. However, the cytotoxic assay, showed a tendency to decrease at higher concentrations of 1.85 (p <0.05) and 3.70 MBq/ml (p <0.01) only in the presence of r-hTSH, coincident with the highest level of uptake. WRO cells were also relatively radioresistant to external irradiation of {sup 60}Co in the range of 0.2-8.3 Gy, with a gradual decrease in function of time for higher doses (10,20 and 40Gy).The data obtained showed little cytogenetic damage in patients upon therapeutic exposure, suggesting a safe and effective treatment for both groups of patients. Patients in group A, however, had a better quality of life by using r-hTSH. In vitro studies with internal ({sup 131}I) and external ({sup 60}Co) irradiation, with or without r-hTSH, point to the need for an alternative therapeutic strategy to overcome the loss of ability of thyroid cells (WRO) to concentrate radioiodine, which is responsible for the failure of radioiodine therapy in patients with DTC. (author)

  6. Synthesis and characterization of La{sub 1-x}Sr{sub x}MnO{sub 3} (x=0,1) for cathode application in solid oxide fuel cells (SOFC); Sintese e caracterizacao de La{sub 1-x}Sr{sub x}MnO{sub 3} (x=0,1) visando sua aplicacao como catodo em celulas a combustivel de oxido solido (SOFC)

    Tarrago, D.P.; Sousa, V.C., E-mail: dptarrago@gmail.co [Universidade Federal do Rio Grande do Sul (LABIOMAT/PPGEM/UFRGS), Porto Alegre, RS (Brazil). Programa de Pos graduacao em Engenharia de Minas. Lab. de Biomateriais; Malfatti, C.F. [Universidade Federal do Rio Grande do Sul (LAPEC/PPGEM/UFRGS), Porto Alegre, RS (Brazil). Programa de Pos graduacao em Engenharia de Minas. Lab. de Pesquisa em Corrosao

    2010-07-01

    Perovskite powders, with composition La{sub 1-x}Sr{sub x}MnO{sub 3} (x=0,1) were obtained via combustion synthesis using sucrose as fuel. In the X-ray diffraction patterns it was observed that in order to obtain a single phase and well crystallized material a calcination in 750 deg C for 3 hours was necessary. BET analysis detected a specific surface area of 45m{sup 2}/g, considerably higher than when obtained with other fuels. SEM micrographs revealed a spongy aspect with a connected porosity in the agglomerates and though TEM micrographs the presence of pores in the particles was verified. The powder compacted with 125MPa and sintered at 1050 deg C for two hours presented a 31% open porosity and the SEM micrographs showed a fine interconnected porosity. (author)

  7. Mineral and/or milk supplementation of fruit beverages helps in the prevention of H2O2-induced oxidative stress in Caco-2 cells La adición de minerales y/o leche a bebidas a base de zumo de frutas ayuda en la prevención del estrés oxidativo inducido por H2O2 en celulas Caco-2

    A. Cilla; J. M. Laparra; A. Alegria; R. Barbera

    2011-01-01

    Introduction: Fruit beverages are commonly supplemented with milk, vitamins and/or minerals in order to improve their healthy effects by providing some bioactive components that can act additively or synergistically against oxidative stress. Aims: To test whether iron, zinc, and milk added to fruit beverages do not affect the cytoprotective effect against oxidative damage to Caco-2 cells through GSH-related enzymes induction and cell cycle progression preservation, in comparison with non-supp...

  8. Criterio y posibilidades del implante celular

    Beatriz Pelacho

    2008-01-01

    Full Text Available Cada año mueren en Europa y EE.UU. como consecuencia de las enfermedades cardíacas más de medio millón de personas. Este alto índice de mortalidad se debe principalmente a la isquemia, responsable del daño cardíaco y de la consecuente pérdida de cardiomiocitos. Aunque algunos grupos investigadores han indicado la existencia de células progenitoras cardíacas en el corazón, el miocardio adulto no es capaz de regenerarse de modo efectivo, siendo su pérdida prácticamente irreversible. Hasta el momento, la única terapia disponible ha estado basada en el empleo de fármacos, los cuales han tenido un efecto paliativo más que curativo, siendo necesario en los casos más graves el trasplante de corazón. Debido a que las opciones de tratamiento son muy limitadas, la última meta sería prevenir estas complicaciones mediante la regeneración de la zona dañada, cuando el daño se produce. El trasplante de células madre o progenitoras es la aproximación del siglo XXI que ofrece una opción terapéutica para la regeneración y recuperación del corazón.

  9. Ada in Introductory Computer Science Courses

    1993-01-01

    M2 111418111 1111111 I s%1 tems to des elop soaftware Systems for IM5. ONhalt oIf dt ufl’wae mownev b f "bs" arn .exti to k ,ulift la Ada. COMPUT...beftjobamdsodeckldthesespienicngamnug them. A celula 101110011ui systm Service in Ada& using an rmniticdawau dipay shows *I tatus. The systm objweaniiimd...liftt aftr of Fucal Nikkao Wirh. Some say Software i - , I, ced a pse-validaed ver. origina soitweim is coded. The idWa is to that Ads is the las gpat

  10. Caracterización de las ?-1,3-glucanosil-transferasas de la familia GH72 implicadas en la remodelación de la pared celular de Schizosaccharomyces pombe

    Medina Redondo, María de

    2008-01-01

    La formación de la pared celular de Schizosaccharomyces pombe requiere la actividad coordinada de enzimas involucradas en la biosíntesis y modificación de sus componentes, entre los que destacan por su abundancia los glucanos. El complejo enzimático ?-glucán-sintasa sintetiza ?-1,3-glucanos lineales, que permanecen desorganizados y solubles en álcali hasta que se establecen enlaces covalentes entre los ?-1,3-glucanos y otros componentes de la pared celular. Las transferasas de la pared celula...

  11. Diseño de placas solares e implementación de un transmisor experimental AX.25 para el 3Cat-1

    Gonzalvez Foguet, Ricard

    2016-01-01

    Explains the design and construction of two types of solar panels for the 3cat1, one type based on commercial high efficiency multi-junction solar cells and other based in UPC Electronic Engineering Department in-house developed solar cells. Also describes the design and implementation of a microcontroller based experimental transmitter to send data packets to the 3cat1 ground station. Diseño y construcción de dos tipos de paneles solares para el 3cat1, el primero basado en celulas solares...

  12. Estudos sobre tuberculose

    A. Fontes

    1917-01-01

    Full Text Available Assim em resumo pensamos que a hipersensibilidade na infeção tuberculosa é a expressão duma reação celular, autonoma e individual, consequente á agressão brusca e á destruição (dijestão incompleta dos toxicos bacilares (proteinas, globulinas e lipoides, em combinação intima ou isoladamente; a adição aos toxicos bacilares de lipoides diversos (cholesterina, lecitina, esters e principios mal definidos existentes no oleo de figado de bacalhau, atenua a sua função hipersensibilidade porque torna esses toxicos mais facilmente incorporaveis á celula sensivel por adsorpção da substancia toxica ao lipoide. Esses corpos penetram assim no interior das celulas levando comsigo ativadores dos processos enzimaticos que não so favorecem uma elaboração dijestiva mais perfeita como ainda uma melhor produção de anticorpos. O aparecimento de pequenas modalidades reacionarias no decurso duma immunisação ativa contra os antijenos saturados por lipoides mostra a necessidade dum processo de desintegração para que a função toxica se manifeste.

  13. Estudio de la expresión de MYBL2 y de miRNAs en la leucemia mieloblástica aguda. Papel del miR-30a en la regulación de MYBL2 y en la proliferación celular

    Llop García, Marta

    2015-01-01

    La leucemia mieloblástica aguda (LMA) es una enfermedad heterogénea caracterizada por la transformación neoplásica de las células progenitoras hematopoyéticas. Los blastos leucémicos se acumulan en sangre periférica y en médula ósea, desplazando a las células sanguíneas normales y provocando insuficiencia medular, que se acompaña de infecciones, anemia y desórdenes de la coagulación. Los blastos leucémicos pueden presentar alteraciones genéticas y epigenéticas que, además de explicar la apari...

  14. Quantificação de células CD 34+ em sangue periférico, produto de aférese e cordão umbilical: estudo comparativo de três diferentes metodologias

    Bacal Nydia S.; Guerra João C. C.; Ferreira Eurípedes; Nozawa Sonia T.; Kanayama Ruth H.; Di Pietro Daniel; Pasternack Jacyr; Hamerschlack Nelson; Rosenfeld Luiz G. M.

    2001-01-01

    A quantificação das células CD34+ em sangue periférico é utilizada para determinar o melhor momento de iniciar a aférese, enquanto que na leucoaférese e no sangue de cordão umbilical determinam a quantidade de células CD34+ para o transplante de células progenitoras. O objetivo deste trabalho foi comparar três diferentes metodologias de quantificação de células CD34+. Foram utilizados três diferentes tipos de amostras: a) 32 amostras de sangue periférico, coletadas de pacientes estimulados co...

  15. La entrada de inversión directa exterior en el sector financiero y su efecto sobre la productividad de la economía mexicana

    Fernando Úbeda Mellina

    2016-02-01

    Full Text Available Los servicios financieros constituyen bienes intermedios (inputs y finales para el conjunto de los sectores de una economía, lo que los dota de una dimensión transversal. Dado que el output generado por estos servicios transversales afecta a la totalidad de la economía, cabe esperar que las externalidades derivadas de la entrada de la inversión directa exterior (ide en el sector financiero sean mayores que las derivadas de la entrada de ide en el sector manufacturero. Sin embargo, hemos obtenido evidencia de que las externalidades negativas de la ide manufacturera son mayores que las derivadas de la ide financiera. Los factores institucionales como la alta aversión al riesgo de la banca y la falta de intensidad en el marco competitivo pueden considerarse factores explicativos del resultado obtenido (Haber y Musacchio, 2005; Schulz, 2006.

  16. Estudo comparativo das inclusões do alastrim e da vacina no macaco (Macacus rhesus A comparison of the inclusion bodies of alastrim and vaccinia in the monkey (Macacus rhesus

    C. Magarinos Torres

    1934-02-01

    Full Text Available Vesiculas e pustulas contendo numerosas inclusões citoplasmicas nas celulas epidermicas, foram regularmente produzidas no macaco (Macacus rhesus, quer com o virus do alastrim, quer com o da vacina, após inoculação endovenosa e sem previa escarificação. O virus do alastrim parece menos virulento para essa especie de macaco que o da vacina. Ao passo que 12 macacos rhesus injetados por via endovenosa com sete amostras diferentes de virus do alastrim, após apresentarem com regularidade um infecção experimental, sobreviveram e se conservaram em boa saúde, a injecção endovenosa do virus da vacina recentemente preparado (polpa bruta produziu a morte em 2, dentre 4 animais experimentados. 2. - Foram notadas diferenças pequenas, mas nitidas, na morfologia das inclusões do alastrim e da vacina, em material fixado no liquido de Helly, incluido em parafina e corado pela hematoxilina-eosina. Dizem elas respeito ao numero de inclusões encontradas em cada celula epidermica e às suas reações de coloração. 3. - As inclusões do alastrim, quando apresentam grandes dimensões, conservam-se unicas ou solitarias no citoplasma das celulas epidermicas do macaco rhesus, e coram-se em tonalidade que varia do azul escuro ao cinzento-azulado. Comtudo, em celulas que sofreram necrose, ou naquelas contendo 2 a 4 inclusões de pequenas dimensões, por vezes elas se mostram coradas em roseo. 4. - As inclusões da vacina, quando em faze adeantada de desenvolvimento, são multiplas nas celulas epidermicas do macaco rhesus e mostram, regularmente, uma policromatofilia caracteristica.1. - Vesicles and pustules containing numerous cytoplasmic inclusion bodies within the epidermal cells were regularly produced in monkeys (Macacus rhesus by intravenous inoculation either of alastrim virus or of recently prepared vaccine emulsion, no previous scarifications being required. Alastrim virus seems less virulent for this species of monkey than the virus of vaccinia is

  17. Abundâncias químicas de uma amostra de nebulosas planetárias em M51

    Uchida, M. M. M.; Costa, R. D. D.; Maciel, W. J.

    2003-08-01

    A derivação de abundâncias químicas de nebulosas planetárias permite a investigação dos processos de enriquecimento químico ocorridos durante a evolução das estrelas progenitoras, que têm massas entre 0.8 e 8 massas solares. Adicionalmente as abundâncias de elementos como oxigênio, argônio ou neônio, que não são produzidos por nucleossíntese na progenitora, refletem a evolução do meio interestelar: estrelas menos massivas, de evolução mais lenta, tipicamente originam-se de um meio interestelar mais pobre. Reportamos aqui a derivação de parâmetros físicos e abundâncias químicas de uma amostra de nebulosas planetárias da galáxia M51, uma galáxia de tipo Seyfert 2 pertencente ao Grupo de Sculptor. As observações foram feitas com o telescópio Gemini Norte, usando o espectrógrafo GMOS no modo multi-objeto. Os resultados indicam uma distribuição de abundâncias análoga àquela das planetárias da Galáxia. A amostra observada não permite estabelecer-se com clareza a existência de um gradiente radial como é esperado pelos modelos evolutivos de galáxias expirais; espera-se que uma extensão desta amostra deva indicá-lo posteriormente. (FAPESP/CNPq)

  18. Study by Monte Carlo simulation of the absorbed dose in cells of breast cancer of the line MDA-MB231, due to sources of {sup 111}In, {sup 177}Lu and {sup 99m}Tc internalized in the nucleus. First results; Estudio por simulacion Monte Carlo de la dosis absorbida en celulas de cancer de seno de la linea MDA-MB231, debida a fuentes de {sup 11I}n, {sup 177}Lu y {sup 99m}Tc internalizadas en el nucleo. Primeros resultados

    Rojas C, E. L.; Perez A, M., E-mail: leticia.rojas@inin.gob.mx [ININ, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico)

    2011-11-15

    The necessity to design innovative treatments and to diagnose the cancer early, has taken to investigate therapies at cellular and molecular level. The design of appropriate radio-molecules to these therapies makes necessary to characterize in way exhaustive radionuclides that they are of accessible production in our country and to study as distributing the dose at cellular level with bio-molecules glued them. In this context, was realized the present work. Using Monte Carlo simulation, the energy deposited in a geometric model of cells of breast cancer was obtained, MDA-MB231, due to different radionuclides. The energy deposited in the nucleus was evaluated, in the cytoplasm and in the membrane of the cell, using the simulation code Monte Carlo Penelope 2008. A punctual source was simulated in the center of the cell nucleus. In each case all the emissions of each radionuclide majors to 400 eV were simulated. The energies deposited by disintegration in the nucleus, cytoplasm, membrane of the cell and in a sphere of 2 cm surrounding the source (in eV) were: 4.30E3, 4.85E2, 1.07E2 and 3.29E4, correspondingly, for the {sup 111}In; 4.46E3, 3.76E3, 1.26E3 and 1.33E5 for the {sup 177}Lu and; 2.12E3, 2.58E2, 9.33E1 and 1.88E4 for the {sup 99m}Tc. We can conclude that if the union of these radionuclides happens to a compound that was internalized to the cell nucleus, the best for therapy at this level is the conjugate with the {sup 177}Lu, followed by that with {sup 111}In and in third place that with {sup 99m}Tc. (Author)

  19. La acción moral. Contraste entre las explicaciones motivacionales dadas por la filosofía y la psicología

    Villegas de Posada, María Cristina

    2004-01-01

    La pregunta de por qué actuamos moralmente ha sido respondida de diferentes maneras tanto por la filosofía como por la psicología. La filosofía presenta explicaciones que pueden agruparse en tres tipos de posiciones: a) internalista o racionalista, derivada de Kant; b) externalista o emotivista, derivada de Hume; c) racionalista y externalista, o combinación de posiciones. La psicología, por su parte, ofrece explicaciones que pueden corresponder a las de la filosofía, pero con una primacía de...

  20. Museografía web 2.0 en Aragón

    Rivero Gracia, María Pilar

    2011-01-01

    Se analiza la utilización de Internet por parte de los museos aragoneses prestando especial atención a las nuevas tendencias derivadas de la implantación de aplicaciones de la Web 2.0 y a la innovación derivada de los proyectos de investigación en curso en el campo de la cibermuseología.Además, se proporcionan referencias a los portales generales de acceso, catálogos on line y visitas virtuales más destacadas.

  1. Los limites del Presidencialismo en México.

    Calzada Herrera, Alejandra.

    2015-01-01

    Se presenta un panorama general del presidencialismo mexicano hasta el día de hoy, en el aspecto de organización, así como las más importantes facultades que el presidente posee, derivadas de la constitución y las leyes derivadas de la misma, que buscan un equilibrio entre los poderes de la Unión Ejecutivo, Legislativo y Judicial. Sus objetivos analizar los antecedentes históricos del presidencialismo en México; así como facultades, características y límites que tiene el poder Ejecutivo en...

  2. A nacionalidade potestativa: o problema da fixação de residência e da opção, a qualquer tempo

    Bezerra Frota Júnior, Francisco

    2004-01-01

    A teoria tradicional da nacionalidade classifica a nacionalidade em originária e derivada. A nacionalidade originária é a que se adquire no momento do nascimento; a nacionalidade derivada, a que se adquire após o nascimento. Esta teoria é insuficiente para explicar o fenômeno da nacionalidade em toda a sua plenitude. Nacionalidade é ato de soberania. É fato jurídico. É o Estado que diz quem são os seus nacionais através de atribuição e de concessão. Os efeitos do ato de atri...

  3. Action of uranium on pre implanted mouse embryos; Accion del uranio sobre los embriones de preimplantacion de raton

    Kundt, Miriam S [Comision Nacional de Energia Atomica, General San Martin (Argentina). Dept. de Radiobiologia

    2001-07-01

    de preimplantacion cultivados in vitro son empleados desde hace algun tiempo para evaluar los efectos de contaminantes ambientales, en especial metales. En este trabajo se ha utilizado este modelo para presentar los efectos citotoxicos, embriotoxicos y genotoxicos del uranio. Los embriones fueron obtenidos mediante superovulacion de hembras hibridas CBA x C57 Bl, apareadas luego con machos NIH y cultivados en medio M16 como medio control. Tres experimentos diferentes se llevaron adelante 'A', 'B' y 'C' utilizando nitrato de uranilo hexahidratado UO{sub 2}(NO{sub 3}){sub 2} 6H{sub 2}O como fuente de uranio. En el experimento 'A' los embriones desde el estadio de una celula se cultivaron durante 120 hs. en la misma placa, conteniendo una concentracion final de uranio de 13, 26, 52, 104 y 208 {mu}gU/ml. En el experimento 'B' los embriones fueron puestos a cultivar desde el estadio de una celula a una concentracion final de uranio de 26, 52 y 104 {mu}gU/ml, a las 24 hs. de cultivo los embriones que pasaron a 2 celulas fueron cambiados a una placa preparada nuevamente, manteniendo las mismas concentraciones de uranio que la anterior, hasta finalizar el periodo de incubacion de 120 hs. En el experimento 'C' los embriones fueron puestos a cultivar desde el estadio de una celula a una concentracion final de uranio de 26, 52 y 104 {mu}gU/ml y fueron cambiados de placa de cultivo cada 24 hs., manteniendo estas placas nuevas las mismas concentraciones de uranio que la primera y el cultivo finalizo a las 72 hs. El clivaje embrionario desde 1 celula a 2 celulas no se ha visto estadisticamente afectado respecto del control, en los 4388 embriones analizados, en los diferentes tratamientos y las diferentes concentraciones de uranio empleadas. Desde el clivaje de 2 celulas en adelante, momento que el embrion comienza a sintetizar su propio ARNm, el retraso en el desarrollo embrionario, el grado de fragmentacion, el porcentaje de embriones atresicos y las malformaciones embrionarias

  4. Prenatal irradiation: radioinduced apoptosis in developing central nervous system; Irradiacion prenatal: apoptosis radioinducida en el sistema nervioso central en desarrollo

    Gisone, P; Dubner, D; Michelin, S; Perez, M R [Autoridad Regulatoria Nuclear, Buenos Aires (Argentina); Barboza, M [Hospital de Clinicas Jose de San Martin, Buenos Aires (Argentina)

    1998-07-01

    produccion de apoptosis en un modelo experimental de irradiacion prenatal. Se irradiaron cultivos primarios de cerebro (rata Wistar, dia 15 de e.g.), en un rango de dosis hasta 2 Gy (Cobalto 60). Se evaluo la respuesta a la incubacion con distintos neuroprotectores. Se estudiaron los siguientes parametros: alteraciones de la morfologia celular, fragmentacion de cromatina y fraccion de celulas apoptoticas. Las celulas irradiadas mostraron condensacion nuclear con presencia de cuerpos apoptoticos. Las corridas electroforeticas evidenciaron un patron de fragmentacion caracteristico ('laddering') con aumento dosis-dependiente en la fraccion de celulas apoptoticas analizadas por citometria de flujo. La incubacion con neuroprotectores no indujo cambios significativos en las concentraciones y los tiempos ensayados. Se analizan los resultados obtenidos. Se discute acerca del rol de la apoptosis, su relacion con la injuria oxidativa y los fenomenos de excitotoxicidad como mecanismo de danio radioinducido en el sistema nervioso central en desarrollo. (autor)

  5. TIC360. Concepto, Conclusiones y Líneas Abiertas.

    Prado, Andrés

    2015-01-01

    TIC360. Concepto, conclusiones y líneas abiertas derivadas de las jornadas de la sectorial TIC de CRUE celebradas en el campus de Toledo de la UCLM. En estas jornadas se trazó una visión 360º de las TIC en la Universidad, contando con todos los agentes implicados

  6. 351. Toracotomía bilateral (técnica de clamshell para abordaje de patología compleja de aorta torácica y arco en un solo tiempo

    S. Villar

    2012-04-01

    Conclusiones: En nuestra experiencia, el abordaje tipo clamshell es útil en tratamiento de patología extensa y compleja de arco aórtico y aorta torácica. Destaca la necesidad de ventilación mecánica prolongada, complicación derivada del tipo de procedimiento.

  7. Simetrías potenciales de un modelo matemático que describe las vibraciones de una viga

    Bruzón Gallego, María de los Santos; Gandarias Núñez, María Luz; Camacho Moreno, José Carlos

    2007-01-01

    En este trabajo presentamos un estudio, desde el punto de vista de la teoría de las simetrías potenciales clásicas y no clásicas para ecuaciones en derivadas parciales, del modelo que describe las vibraciones de una viga.

  8. Una aplicación de las funciones débilmente contractivas a problemas de valor en la frontera de funciones con valores en intervalos

    Vladimir Angulo-Castillo

    2014-01-01

    Full Text Available Se estudia la existencia y unicidad de soluciones para problemas de valor en la frontera asociadas a ecuaciones diferenciales de funciones con valores en intervalos, usando la derivada de Hukuhara y algunos teoremas de punto fijo de funciones débilmente contractivas definidas en conjuntos par- cialmente ordenados.

  9. LO APEIRON: VOZ DE GRECIA CLÁSICA EN LA CIENCIA CONTEMPORÁNEA

    ROMÁN CASTAÑEDA-SEPULVEDA

    2012-07-01

    Full Text Available Se analiza el paralelo entre lo apeiron, designado por Anaximandro como arche cósmico y las concepciones sobre el universo derivadas de los desarrollos científicos, particularmente del siglo XX. Este análisis sugiere la vigencia del pensamiento de Anaximandro, quien lo promulgó hace 26 siglos.

  10. FORMACION Y CONTRASTACION DE LAS TEORIAS CIENTIFICAS EN CONTABILIDAD

    MONTESINOS JULVE, VICENTE

    2005-01-01

    Los problemas de formacion y contrastacion  de las teorias cientifcas en contabilidad los abordaremos a continuacion separando los propios del conocimiento descriptivo de los de tipo normativo. posteriormente nos ocuparemos del enlace entre ambos tipos de teorias y concluiremos con algunas consideraciones sobre la naturaleza cientifica de nuestra disciplina,derivadas de los planteamientos contemplados.

  11. Sistemas distribuídos aplicados à compressão e recuperação de imagens - DOI: 10.4025/actascitechnol.v30i1.3178

    Fabio Jorge Assad Gostaldon

    2008-05-01

    Sistemas distribuídos aplicados à compressão e recuperação de imagens by Eduem is licensed under a Creative Commons Atribuição-Uso Não-Comercial-Vedada a Criação de Obras Derivadas 2.5 Brasil License.Based on a work at periodicos.uem.br.

  12. El uso de coxibs, en la artritis y artrosis, sólo es coste-efectivo en pacientes con antecedentes de hemorragia digestiva

    Manuel Ridao

    2014-09-01

    Conclusiones: La reducción de riesgo de sufrir una complicación GI derivada de la utilización de coxibs no compensa sus elevados costes en comparación con los AINEs convencionales. Sólo en el grupo de pacientes con úlcera sangrante el resultado del ratio coste utilidad incremental es aceptable.

  13. The Use of Tritium-Labelled Thymidine in Studies on the Synthesis of Deoxyribonucleic Acids; Emploi de la Thymidine Tritiee Dans L'etude de la Synthese de l'Acide Desoxyribonucleique; 0418 0441 043f 043e 0414 ; Empleo de Timidina Tritiada para Estudiar la Sintesis de los Acidos Desoxirtibonucleicos

    Bianchi, P. A.; Crathorn, A. R.; Shooter, K. V. [Chester Beatty Research Institute, Institute of Cancer Research, London (United Kingdom)

    1962-02-15

    balayage continu. Les deux methodes de mesure ont donne des resultats sensiblement differents. Pour chaque cellule, l'activite due au tritium, calculee d'apres les autoradiographies, a toujours paru superieure a celle de l'ADN isole. En mesurant ensuite a l'aide du compteur a balayage continu l'activite de cellules entieres, apres lavage et homogeneisation, on a obtenu des chiffres qui concordaient avec les resultats de l'autoradiographie. Il semble donc, en l'occurrence, que l'autoradiographie ne permette pas de mesurer de maniere satisfaisante la synthese de l'ADN. On a etudie l'activite associee, autre que celle de l'ADN, et entrepris sur d'autres types de cellules des etudes analogues de l'activite totale due au tritium et de l'activite de l'ADN isole; des effets similaires ont ete observes. A partir de ces donnees, on a pu distinguer plusieurs phases dans le processus de synthese : 1 Degree-Sign incorporation initiale de la thymidine a la cellule; 2 Degree-Sign phosphorylation en deux etapes au moins; 3 Degree-Sign formation d'ADN par polymerisation de la thymidine phosphorylee. Ainsi, on simplifierait a l'exces en supposant que l'incorporation de thymidine a la cellule permette de mesurer la synthese de l'ADN; il semble cependant qu'en utilisant cet indicateur on puisse obtenir des indications utiles sur les etapes preliminaires du processus. (author) [Spanish] En el curso de estudios sobre la biosintesis del acido desoxirribonucleico se han realizado algunos experimentos, utilizando celulas asciticas de Ehrlich, para investigar la fijacion e incorporacion de timidina-{sup 3}H. Despues de incubar in vitro las celulas marcadas con este compuesto, se han tomado autorradiografias de las mismas; tambien se ha aislado el acido desoxirribonucleico y se ha medido la actividad del {sup 3}H utilizando un contador de flujo. Al comparar los dos metodos de medicion, se advierte una marcada discrepancia; la actividad del {sup 3}H por celula, calculada a base de las

  14. Cell death induced by tamoxifen in human blood lymphocytes cultivated in vitro = Morte celular induzida pelo tamoxifeno em linfócitos humanos cultivados in vitro

    Selma Candelária Genari

    2010-10-01

    Full Text Available Many chemotherapeutic agents with a potential against solid tumors or leukemia can cause lymphopenia. Tamoxifen (TAM is a synthetic non-steroidal anti-estrogen drug employed in female breast cancer treatment. The present study investigated the capacity of TAM to induce cell death in human lymphocytes cultivated in vitro. Lymphocytes were obtained from young (25-30 years; n = 3 and elderly women (58-77 years; n = 3 and cultivated for 24 or 48h, with or without TAM (20 ƒÊM. After the culture, cell viability, immunocytochemical response and ultrastructure were evaluated. TAM affected lymphocytes in a time- dependent manner, and cells obtained from elderly women were the most sensitive to TAM. Immunocytochemicalanalysis evidenced higher frequency of apoptosis in treated cells, and the ultrastructural study revealed autophagic vacuoles, differing from the controls. In summary, the treated lymphocytes were affected by TAM, leading to cell death by apoptosis and autophagy.Muitos agentes quimioterapicos com potencial contra tumores solidos ou leucemias podem causar linfopenia. O Tamoxifeno (TAM e um agente antiestrogeno nao-esteroidal empregado no tratamento de cancer de mama feminino. O presente trabalho investigou a capacidade do TAM em induzir morte celular em linfocitos humanos cultivados in vitro. Oslinfocitos foram obtidos de mulheres jovens (25-30 anos; n = 3 e idosas (58-77 anos; n = 3 e cultivados por 24 ou 48h, com ou sem TAM (20 ƒÊM. Apos a cultura, foram analisadas a viabilidade celular, a resposta imunocitoquimica e a ultraestrutura. Os resultados indicam que o Tamoxifeno induziu morte celular em linfocitos de ambos os grupos, entretanto, as celulas das mulheres idosas apresentaram-se mais sensiveis ao tratamento. A analise imunocitoquimica mostrou maior frequencia de apoptose nas celulas tratadas e o estudo ultraestrutural revelou vacuolos autofagicos nos linfocitos expostos ao Tamoxifeno. Em conclusao, nosso estudo revelou que o TAM

  15. Gestão organizacional sob a lógica da competência: aplicação na pequena empresa.

    Mariana Musetti Munck

    2008-02-01

    Full Text Available Este estudo, sustentado nas premissas teoricas do modelo de gestão por competencias, objetiva explorar, descrever e mudar a sistematica de execução das atividades de uma pequena empresa de consultoria. Orientando-se por autores que propoem a operacionalização do conceito de competencias nas organizacões, construiram-se quadros de referencias para as celulas da organização de modo que houvesse mais transparencia e consistencia nas ações de gestão, e isso representa um grave problema das pequenas empresas. Os quadros são compostos de atributos como missão, atribuições, contribuições, indicadores de resultados e competencias, todos definidos com base nas estrategias e nos objetivos almejados pela organização. Ante a proposta de não apenas explorar e descrever, mas tambem de mudar, o estudo utilizou como orientação metodologica a pesquisa-ação. Esse metodo não se limita apenas a descrever uma situação, mas tambem pretende desencadear, em certos casos, mudancas no seio da coletividade envolvida. O proprio processo de busca e os resultados alcancados demonstraram, a principio, que a estruturação de uma empresa por competencias gera turbulencias iniciais, principalmente pela radicalidade da mudança (neste caso e pelas particularidades do conceito. A nova estrutura tem provocado mudanças culturais, sobretudo na açao dos gestores que tem agora informações claras sobre as atribuições e exigencias cabiveis a cada celula, bem como de seus respectivos indicadores de desempenho.

  16. Tritiated Thymidine as Tracer in DNA Metabolism and Cell Dynamics of Experimental Myeloid Leukaemia; Emploi de la Thymidine Tritiee comme Indicateur pour l'Etude du Metabolisme de l'ADN et de la Dynamique des Cellules dans la Leucemie Myeloide Experimentale; 0422 0440 0438 0442 0414 ; Empleo de la Timidina Tritiada como Indicador para Estudiar el Metabolismo del Acido Desoxirribonucleico y la Dinamica Celular en la Leucemia Mieloide Experimental

    Zajicek, G.; Rosin, A.; Gross, J. [Department of Experimental Medicine and Cancer Research, Hebrew University, Hadassah Medical School, Jerusalem (Israel)

    1962-02-15

    disposent probablement pas d'une quantite suffisante de thymidine dans le liquide ascitique. Les auteurs etudient la dichotomie entre la synthese du complement entier de l'ADN et la division subsequente de la cellule. (author) [Spanish] El tritio se utiliza en Israel como indicador para estudiar una gran variedad de problemas biologicos. Los autores describen en particular los resultados de unas investigaciones en que se ha utilizado timidina tritiada para estudiar la dinamica celular en la leucemia mieloide, inducida con lines experimentales, y analizar el mecanismo de la incorporacion de esa sustancia en el acido desoxirribonucleico de celulas leucemicas y de celulas de tumores asciticos de Ehrlich. Las celulas leucemicas se marcaron in vivo inyectando en la vena yugular de ratas timidina tritiada a razon de 1 {mu}curie/g de peso corporal. Se evaluo la velocidad de aparicion de las celulas marcadas en la sangre de la periferia y en el tumor ascitico de los animales. En otros experimentos se determino la velocidad de dilucion del indicador en los nucleos, lo que permitio calcular el tiempo de duplicacion de la poblacion de mielocitos. La dinamica de las celulas transfundidas se investigo inyectando mielocitos marcados en la vena yugular de ratas normales y leucemicas. Se midio su velocidad de desaparicion de la sangre. Se examinaron varios organos para ver si contenian celulas marcadas y se observo que poco despues de la inyeccion las celulas son principalmente captadas por los pulmones, despues por el bazo y, en menor grado, por el higado. Pasadas 24 h no se pudieron detectar celulas marcadas en ningun organo. De este modo, se obtuvo informacion sobre el comportamiento de los mielocitos leucemicos en distintos organos de animales normales y leucemicos. En experimentos realizados in vitro, se anadio a una suspension celular timidina tritiada en una concentracion de 1 {mu}curie/ml. Durante la marcacion in vitro se comprobo que el numero de celulas marcadas es 40 veces mayor

  17. Uma abordagem baseada em procura directa direccional a problemas com ruído

    Marcos, Samuel Pacheco Marques Vaz

    2016-01-01

    Em aplicações a nível industrial, principalmente em engenharia, é frequente ser-se confrontado com problemas de optimização desafiadores onde, em particular, a avaliação da função objectivo pode estar contaminada com ruído numérico. A presença deste ruído inviabiliza a utilização de métodos de optimização baseados em derivadas. A procura directa direccional (PDD) é um dos métodos que não recorre a derivadas. Nesta dissertação procurou-se avaliar o seu desempenho numérico na opt...

  18. Molécula HLA-G y su importancia en la inmunorregulación de la unidad feto-materna. Aplicaciones en inmunoterapia celular

    Macedo Pereira, Jacqueline

    2016-01-01

    OBJETIVOS El objetivo principal de esta tesis doctoral consiste en determinar la presencia de la proteína HLA-G en la superficie celular de células madre CD34/CD133, células dendríticas mieloides y plasmacitoides, células dendríticas derivadas de células CD34/CD133 y derivadas de monocitos de sangre de cordón umbilical y sangre periférica materna, por técnicas de citometría de flujo y la expresión de la proteína HLA-G soluble en plasma de sangre de cordón umbilical por técnicas de ELISA. MATE...

  19. 139. Complicaciones Neurológicas Mayores en Octogenarios Tras Cirugía Cardíaca: ¿Es la Edad un Factor Limitante?

    G. Laguna

    2012-04-01

    Conclusiones: la incidencia de complicación neurológica mayor no es significativamente superior en nuestra población de octogenarios. Mientras en menores de 80 años la existencia de enfermedad vascular es el principal factor determinante, la inadecuada oxigenación cerebral, derivada de situaciones de anemia preoperatoria, parece influir más en la presencia de complicaciones neurológicas en los mayores de 80 años.

  20. La globalización y la gestión financiera internacional

    Carlos Eduardo Martínez Fajardo

    2003-06-01

    Full Text Available Este artículo constituye una reflexión acerca de la incidencia del proceso de globalización en la evolución reciente de las finanzas internacionales y en la expansión apoyada en la mayor capacidad de gestión de las empresas multinacionales. Dicho proceso se analiza de acuerdo con las pautas derivadas del reordenamiento de la estructura mundial de poder y su incidencia en el sistema financiero internacional.

  1. Body dissatisfaction differences and similarities among people with eating disorders, people with gender dysphoria and university students

    Rabito Alcón, María Frenzi; Rodríguez Molina, José Miguel

    2016-01-01

    Reconocimiento-No comercial-SinObraDerivada To subjects with gender dysphoria, body image is an important aspect of their condition. These individuals at times report high body dissatisfaction, similar to individuals with an eating disorder. In total, 61 subjects with gender dysphoria, 30 subjects with an eating disorder, and 40 healthy subjects were evaluated. We parted from the hypothesis that gender dysphoria subjects present more body dissatisfaction than the control group, but less t...

  2. A fenomenologia revelada: Georges Bataille e a alteração da sociologia

    Joron, Philippe

    2010-01-01

    Nesse artigo propomos refletir sobre à fenomenologia batailleana propriamente dita, ou seja, trabalhar na sua distinção da sociologia convencional ou ortodoxa. O objetivo é contribuir na construção de uma história das ideias sociológicas que permitam, pela obra de Georges Bataille, preencher algumas das lacunas de definição derivadas da ciência durkheimiana.

  3. Plasticidad de la palabra

    Serna Arango, Julián

    2002-01-01

    Partiendo de la polisemia de las palabras y de la acción recíproca de unas palabras sobre otras en el evento comunicativo, se analizan la metáfora y la ironía, los implícitos y los excedentes de sentido de orden supcaproposicional, se reconoce la ambigüedad de allí mismo derivada, pero también las posibilidades de comunicación abiertas.

  4. Descripci??n del dolor y el tono vagal en mujeres supervivientes de c??ncer de mama y efectos f??sicos de un programa de fisioterapia acu??tica

    Caro Mor??n, Elena

    2015-01-01

    El diagn??stico precoz, los avances en los tratamientos y la prevenci??n de la recurrencia son factores responsables del aumento de la supervivencia en las pacientes de c??ncer de mama. Estas pacientes sufren numerosas secuelas o trastornos cr??nicos relacionados con la propia enfermedad o derivadas de los tratamientos recibidos que repercuten sobre su calidad de vida. Las mujeres supervivientes de c??ncer de mama (SCM), objeto de nuestro estudio, presentan disfunciones card??a...

  5. Empleo y economías de aglomeración: el caso de la industria de la carne, productos lácteos y conservas alimenticias, 1988-2003

    Rogelio Varela Llamas

    2009-01-01

    Mínimos Cuadrados Generalizados, se obtienen resultados que sugieren que las economías externas derivadas de la especialización y diversidad productiva no afectan positivamente al empleo; con excepción de la industria de conservas alimenticias. Asimismo, se determina que el empleo en el resto de las ramas del subsector 31 presenta un efecto positivo y significativo sobre cada una de las tres ramas estudiadas.

  6. Psicología aplicada en dietoterapia

    Micó, Lydia; Bretó, Patricia; Melero, Yolanda; Soriano, José Miguel

    2012-01-01

    Uso del video educativo y el podcasting como fortalecimiento en el aprendizaje de la Dietoterapia. En determinadas circunstancias, algunos pacientes que realizan un tratamiento dietoterapéutico, requieren ser derivadas a una psicóloga con el fin de poder materializar con éxito el tratamiento en la intervención nutricional. En este video se explica los procedimientos que permitan derivar a la psicóloga y como realiza ella el tratamiento.

  7. Microbiota intestinal en la enfermedad renal crónica

    Secundino Cigarran Guldris

    2017-01-01

    En este artículo se revisan la situación de la microflora intestinal en la ERC, la alteración de la barrera intestinal y sus consecuencias clínicas, los efectos deletéreos de las toxinas urémicas derivadas de la microflora intestinal, así como las posibles opciones terapéuticas para mejorar esta disbiosis y reducir las complicaciones de la ERC.

  8. Reconocimiento geotécnico del terreno

    Suriol Castellví, Josep; Lloret Morancho, Antonio; Josa Garcia-Tornel, Alejandro

    2007-01-01

    El presente texto trata de introducir al estudiante de Geotecnia a la problemática derivada del estudio del terreno como medio natural. Surge entonces la necesidad de transformar las propiedades del terreno en parámetros útiles al cálculo geotécnico. Los metodos de reconocimiento y los ensayos descritos tienen como objeto dar la solución a dicha problemática.

  9. Respuesta educativa a los alumnos con trastornos del espectro autista en la escuela ordinaria

    Seseña Cuerda, María

    2013-01-01

    En las aulas, cada vez son más frecuentes alumnos que presentan necesidades educativas especiales derivadas del Trastorno del Espectro Autista. Estos trastornos se caracterizan por su gran heterogeneidad, presentando déficits persistentes en la comunicación e interacción social, así como patrones de comportamiento, intereses o actividades restringidas y repetitivas. Todo ello se manifiesta en edades tempranas, condicionando en gran medida el funcionamiento cotidiano y por tanto el proceso edu...

  10. Ejecución de créditos derivados de contratos bancarios

    Gómez de Liaño Diego, Rosa

    1998-01-01

    El tráfico mercantil y su desarrollo ha dado lugar a la implantación de relaciones y situaciones contractuales que se han abierto paso muy deprisa, y forman parte de nuestro entorno y dentro de esa corriente los contratos bancarios, que tienen como objeto principal la concesión de crédito , han adquirido una dimensión principal, adoptando formas y peculiaridades derivadas de las exigencias de cada momento.

  11. Una aproximación al mejoramiento de la cadena de abastecimiento. centro de distribución de repuestos GM Colmotores

    Ruiz Barreto, Andres Felipe

    2014-01-01

    Este trabajo de investigación se desarrolló con el fin de buscar alternativas de mejora para la operación de despacho de repuestos hacia los concesionarios del Centro de Distribución de Repuestos de GM Colmotores, investigando posibles formas para mantener y aumentar los estándares de productividad de este CEDI, mientras se mitiga la variabilidad de los despachos derivada de la inestabilidad de la demanda de los concesionarios y sus clientes.

  12. El cáncer colorrectal en España. Costes por incapacidad temporal y opciones preventivas desde las empresas

    M.T. Vicente-Herrero

    2013-04-01

    Conclusiones: Sirvan los resultados para valorar la utilidad de la implantación de estrategias de apoyo a la sanidad pública para una mayor reducción de la prevalencia, mortalidad y mejora de la calidad de vida de los afectados y sus familias, junto con un ahorro económico derivado de la reducción de la IT derivada del cáncer colorrectal.

  13. Leishmaniasis cutánea zosteriforme causada por Leishmania (Viannia panamensis y Leishmania (Viannia braziliensis: reporte de tres casos

    Camilo Andrés Morales

    2014-09-01

    Se presentan tres casos de leishmaniasis cutánea zosteriforme en los que se identificaron Leishmania panamensis y Leishmania braziliensis como especies infectantes. La sospecha epidemiológica derivada de la procedencia de los pacientes, así como la sospecha clínica a partir del reconocimiento de una presentación infrecuente de la enfermedad, permitieron hacer el diagnóstico.

  14. COSTE SALARIAL Y RENTA DISPONIBLE DEL TRABAJADOR

    Antonio Pérez Carrasco

    2009-02-01

    Full Text Available Se expone la relación entre el coste laboral y la renta disponible del trabajador, así como el análisis de las consecuencias sobre el salario derivadas de la cotización a la Seguridad Social. The relationship between labour costs and disposable income of the workers is exposed as well as the analysis of the impact on wages resulting from contributions to Social Security.

  15. Analisis del efecto de los mercados de agua sobre el beneficio de las explotaciones, la contaminacion por nitratos y el empleo eventual agrario

    Calatrava-Leyva, Javier; Colmenero, Alberto Garrido

    2001-01-01

    RESUMEN: La evidencia disponible sobre los efectos externos de los mercados de agua actualmente en funcionamiento es contradictoria. Algunos trabajos demuestran que el intercambio de agua reduce la contaminación derivada de los sistemas productivos del regadío, mientras que otros concluyen lo contrario. El uso combinado de tasas sobre el input contaminante y la implantación de un mercado de agua plantea incentivos a los productores con resultados ambiguos, entre otras razones porque agua y fe...

  16. Las emociones autoconscientes en niños y niñas españoles /as de 7 a 11 años

    Tena López, Elena

    2017-01-01

    Las emociones autoconscientes aparecen más tarde en el desarrollo evolutivo que las primarias, y van cambiando a lo largo del ciclo vital. Este tipo de emociones se consideran emociones secundarias o derivadas por requerir de habilidades cognitivas complejas. Ayudan al individuo tanto a realizar evaluaciones sobre su propia identidad, como sobre sus acciones o conductas, por lo que también se las ha denominado emociones autoevaluativas. Asimismo, surgen en contextos interpersonales de relevan...

  17. NEUROSOCIEDAD EN PERSPECTIVA COMPLEJA.

    Oscar J. Fernández Galíndez

    2010-01-01

    Full Text Available Las neurociencias devienen en paradigma emergente, visto este como cosmovisión, la cual contribuye en configurar un nuevo estado postindividual y por consiguiente junto a otros, ayuda a entender las relaciones culturales derivadas no solo de las neurociencias sino del pensamiento cibernético el cual desde la interface “inteligencia artificial”, contribuye a demarcar un nuevo orden y una nueva realidad, que es y no es plural.

  18. La formación de la enfermera en salud ocupacional

    Toro Restrepo, Marta Lucía

    1993-01-01

    El artículo trata sobre la formacíon del recurso profesional de enfermería en salud ocupacional como una necesidad derivada de las condiciones de trabajo de la población. Se plantea la formación y utilización del mismo como una responsabilidad de instituciones empleadoras y formadoras. Por último define cinco retos de la enfermería ocupacional para el siglo XXI

  19. El modelo de inventarios de mercancías considerando la interacción entre procesadores y especuladores

    César Revoredo Giha

    2008-01-01

    Este artículo considera una versión alternativa del modelo de inventarios de mercancías bajo expectativas racionales, donde tanto especuladores como firmas procesadoras almacenan productos. El modelo identifica tanto los inventarios llevados por los procesadores como aquellos descritos por el modelo de oferta de inventarios. Sin embargo, en lugar de usar el motivo de conveniencia (retornos por conveniencia), la demanda por inventarios es derivada a partir de un modelo microeconómico de invent...

  20. Evolución de la intervención psicológica de la artitris reumatoide

    Japcy Margarita Quiceno

    2011-01-01

    enfoques de intervención que se han centrado en la expresión emocional abierta de la afectividad negativa. Se termina resaltando la importancia del desarrollo de programas de intervención en pacientes con artritis reumatoide, basados en la potenciación de las emociones positivas, la resiliencia y otras variables derivadas de la psicología positiva.

  1. Acceso a la información: hacia la democratización de la administración pública

    Ferreyra, Leandro E.

    2013-12-01

    Full Text Available El trabajo se encuentra estructurado en tres partes. En la primera se intenta delimitar un concepto de derecho de acceso a la información pública y de las complejidades derivadas del mismo de acuerdo a lo resuelto y normado en diversos sistemas. En la segunda, se analiza el régimen argentino y sus déficits. En la tercera, se esbozan consideraciones y propuestas en base a lo expuesto anteriormente.

  2. Avances en Biología Osea: El Osteoclasto

    José Vicente Ballesteros; Manuel Socha; Ana Katherine Serrano; Enrique Ardila

    1999-01-01

    El osteoclasto es una célula multinucleada encargada de la resorción ósea que tiene una morfología especifica, derivada del sistema hematopoyético que está altamente relacionada con factores locales de crecimiento y con hormonas sistémicas como la PTH, la Calcitonina y la Vitamina D, implicada en la fisiopatología de ciertas entidades como la enfermedad de Paget, la hipercalcemia maligna y la osteoporosis.

  3. Restauración del tejido gingival a partir de fibroblastos autólogos

    Eduvigis Solórzano N

    2013-12-01

    Full Text Available El interés de la investigación básica biomédica ha tenido un crecimiento vertiginoso en los últimos años y la odontología no escapa a esta motivación, es así como estamos en la búsqueda de alternativas de tratamiento a defectos de tejidos blandos y óseos que permitan resultados satisfactorios a nuestros pacientes desde el punto de vista estético y funcional, ya que en ocasiones, las limitaciones en la cantidad de tejido disponible para autoinjerto no permiten el éxito esperado, es por ello que la interdisciplinariedad ha permitido la exploración de nuevas fuentes de tejido bucal. Las investigaciones actuales se enfocan en el desarrollo y caracterización de tejidos equivalentes a la mucosa bucal y se ha demostrado que los fibroblastos del conectivo gingival participan eficientemente en la reparación de los tejidos, razón por la cual se están utilizando con mucho éxito en medicina regenerativa; así como también el aislamiento de células progenitoras mesenquimáticas a partir de diversos tejidos bucales, entre ellos el más utilizado, la pulpa dental.

  4. Modificación de conocimientos sobre su dieta alimenticia en madres de lactantes Modification to knowledge on nourishing diet of infant mothers

    Adriana Sarda Prada

    2011-09-01

    Full Text Available Se realizó una intervención educativa sobre aspectos relacionados con la alimentación, dirigida a 25 madres de lactantes que pertenecían a un consultorio médico del Policlínico Universitario "30 de Noviembre" de Santiago de Cuba, desde junio de 2008 hasta octubre de 2009, para lo cual se desarrolló un programa de clases durante 3 meses. Los encuentros sistemáticos garantizaron modificar positivamente los conocimientos de la mayoría de las progenitoras sobre la adecuada selección de los componentes de su dieta para alimentar y nutrir a sus neonatos a través de la lactancia materna. Se recomendó efectuar a largo plazo una investigación para evaluar el impacto de ese adiestramiento en el crecimiento y desarrollo de sus hijos.An educational intervention on aspects related to nourishment addressed to 25 infant mothers belonging to a doctor's office at "30 de noviembre" University Polyclinic in Santiago de Cuba was carried out from June, 2008 to October, 2009, in which case a class program was performed during 3 months. Systematic encounters guaranteed the positive modification to knowledge of most mothers about the appropriate selection of their diet components to feed and nourish their neonates through breastfeeding. It was recommended to perform a long-term research to assess the impact of that training for the growth and development of their children.

  5. Normal development of fetal hepatic haematopoiesis during the second trimester of gestation is upregulated by fibronectin expression in the stromal cells of the portal triads El desarrollo normal de la hematopoyesis hepática fetal durante el segundo trimestre de embarazo está regulado al alza por la expresión de fibronectina en las células del estroma de las tríadas portales

    D. Tamiolakis

    2007-10-01

    -renovación, la proliferación y el crecimiento de las células madre hematopoyéticas, al interactuar con las células progenitoras hematopoyéticas. Se sabe que las glucoproteínas de la MEC producidas por las células del estroma desempeñan un papel crítico en la regulación del crecimiento y la diferenciación celulares. Se han documentado numerosos factores solubles y de membrana que regulan directamente la hematopoyesis, pero se sabe poco de la actividad de las células del estroma hepático y de la proteína (fibronectina de la matriz extracelular en el feto en relación con la hematopoyesis hepática. La unión de las células eritroides tardías a la fibronectina está bien tipificada y se cree que es crítica para las etapas terminales de la diferenciación eritroide. La intención de este artículo es determinar el papel de la fibronectina en la proliferación y diferenciación hematopoyética del hígado fetal en las distintas etapas del desarrollo. Material y método: examinamos y comparamos la expresión inmunohistoquímica de fibronectina en los campos portales del estroma hepático durante los trimestres primero, segundo y tercero del embarazo en relación con la aparición de células progenitoras hematopoyéticas CD34, progenitoras del estroma y endoteliales vasculares, respectivamente. Resultados: nuestros resultados mostraron una diferencia cuantitativa en cuanto a expresión de fibronectina en el estroma del tejido conjuntivo de los campos portales en el segundo trimestre de embarazo respecto al primero (p < 0,0001, prueba de la t y respecto al tercero (p < 0,0001, prueba de la t. Se hallaron también cambios similares en cuanto a la expresión de CD34 respecto al primer (p < 0,0001, prueba de la t y el tercer trimestres (p < 0,0001, prueba de la t, lo que indica la participación directa de la fibronectina en el mantenimiento de la actividad hematopoyética. Conclusiones: nuestros datos aportan pruebas de que un componente de la glucoproteina de la MEC, la

  6. Opinião do pai sobre o aleitamento materno

    ROSINEIDE SANTANA DE BRITO

    2006-01-01

    Full Text Available Estudio cualitativo desarrollado en Natal/RN con 13 hombres cuyos hijos estaban en período de lactancia natural. Tuvo por objetivo verificar la opinión del padre sobre la lactancia materna. Los datos se obtuvieron a partir de entrevista parcialmente estructurada y tratados siguiendo la técnica de análisis temático propuesta por Bardin. Los padres atribuyeron valores importantes a la lactancia relacionándolos al hijoya la compañera. Con relación al niño, verificamos conocimiento acerca de los beneficios de la leche materna como un alimento nutritivo, que promueve el crecimiento JI desarrollo infantil, determina la salud actual y favorece la vinculación entre el niño JI su madre. Con relación a la compañera, los entrevistados dijeron que la lactancia materna contribuye para que se estable el vínculo afectivo zca entre lactante y progenitora, como también, para la realización de la maternidad. Por consiguiente, afirmamos que los padres expusieron opiniones positivas acerca de la lactancia materna, las cuales pueden favorecer la promoción JI contribuirpara el suceso de la lactancia materna.

  7. Citomegalovirus: de la primoinfección a la retinitis

    Omer Rodríguez Martínez

    Full Text Available Una vez sucedida la primoinfección, el citomegalovirus se establece latente en las células mieloides progenitoras, y la reactivación viral intermitente procedente de macrófagos activados o células dendríticas es controlada por una fuerte respuesta viral específica de células CD4 y CD8. La retinitis por citomegalovirus está caracterizada por una necrosis retinal como consecuencia de efectos citopáticos virales que ocurre en pacientes en quienes la función de células T está comprometida, como resultado de trasplantes de órganos, SIDA o tratamiento inmunosupresor. El diagnóstico de retinitis por citomegalovirus puede ser confirmado por amplificación del ADN viral en muestras de humor acuoso. El tratamiento de la retinitis por citomegalovirus se basa en la actualidad en la reconstitución del sistema inmune con la terapia TARGA y combinado a una terapia anticitomegalovirus (ganciclovir, foscarnet, cidofovir y valganciclovir. El citomegalovirus está también implicado en dos formas de enfermedad del segmento anterior en adultos inmunocompetentes llamado uveítis anterior por citomegalovirus y queratitis endotelial por citomegalovirus.

  8. Leucemia Mielóide Crônica: transplante de medula óssea Cronic Myeloid Leukemia: bone marrow transplantation

    Francisco J. P. Aranha

    2008-04-01

    Full Text Available A única terapia curativa para Leucemia Mielóide Crônica ainda é o transplante de células hematopoéticas progenitoras (TCHP; os atuais resultados com uso do imatinibe são suficientes para indicarmos o TCHP como um tratamento de segunda ou terceira linha. A decisão de realizar TCHP existe em uma variedade de momentos: falha em se conseguir remissão hemtológica, citogenética ou molecular, ou quando se perde a melhor resposta conseguida ou por progressão da doença para uma fase avançada. Há decisão também de como transplantar. Nesta revisão apontamos algumas destas decisões e as atuais controvérsias.Although the only curative therapy for chronic myeloid leukemia remains allogeneic stem cell transplantation (allo-SCT, the results of imatinib in newly diagnosed patients are sufficiently impressive to have displaced allo-SCT to second or third-line treatment. Patients now arrive at a decision for transplantation in a variety of disease situations: failing to achieve certain hematological, cytogenetic and molecular remission by some pre-determined timepoint, having lost a previous best response or due to progression to an advanced phase. The decision is also how to transplant. In this review article, the evidence supporting some of these decisions and current controversies are discussed.

  9. Niñas y niños involucrados en procesos de sustracción familiar en México

    Edith Carrillo

    2011-01-01

    Full Text Available Mi propósito central en este artículo es aportar elementos para la reflexión respecto a la situación que enfrentan las niñas y los niños que se ven involucrados en procesos de sustracción familiar, es decir, en contextos de conflicto por su custodia. Para ello, analicé la configuración de la sustracción familiar a partir de las narrativas de los progenitores y progenitoras, y de los funcionarios y funcionarias de la administración pública, ubicadas en las instancias que tienen injerencia en esta problemática. Con este artículo busco enfatizar que, si bien los hijos e hijas o nietos y nietas son el supuesto centro de esta disputa, son en realidad los sujetos menos tomados en cuenta en esta situación, ya que lo que se pone en juego y lo que determina este conflicto no es su bienestar o "interés superior", sino el establecimiento del orden de género y de las relaciones de poder en los ámbitos públicos y privados.

  10. The Treatment of Cancer by a Radioactive Drug: Tritium-Labelled Tetra-Sodium 2-Methyl-1:4-Naphthaquinol Diphosphate; Traitement du Cancer par un Remede Radioactif: Le Diphosphate Tetrasodique de Methyl-2 Naphtoquinone-1,4 Tritie; 041b 0435 0447 0435 043d 0414 ; Tratamiento del Cancer con la Sal Tetrasodica del Acido 2-Metil-1,4-Naftoquinon Difosforico Marcada con Tritio

    Marrian, D. H.; Marshall, Barbara; Mitchell, J. S.; Simon-Reuss, I. [Department of Radiotherapeutics, University of Cambridge, Cambridge (United Kingdom)

    1962-02-15

    tetrasodica del acido 2-metil-l,4-naftoquinon-difosforico (''Synkavit'' Roche), asi como algunos de los metodos que se han empleado para marcar este y otros compuestos analogos. Sintetizaron el compuesto tritiado en forma de obtener una substancia radioquimicamente pura de 28 c/mmol (1 atomo de tritio por molecula) de actividad especifica. Demuestran que este producto penetra muy rapidamente en las celulas vivas, tanto in vivo como in vitro y que, en igualdad de condiciones los cultivos de celulas malignas incorporan en grado mucho mayor el compuesto marcado que los cultivos de celulas normales. Describen las investigaciones preliminares del empleo clinico de ese producto en casos avanzados de tumores malignos que suelen ser refractarios a otros tratamientos, observandose que la medula osea absorbe menor cantidad del compuesto que el tumor (en algunas ocasiones, hasta cinco veces menos). (author) [Russian] Dejstvie tetrasoda - 2-metil-1: 4- naftagidrohinondifosfata (Sinkavit - proizvodstvo Roshe) v kachestve radio- senitajzera obsuzhdaetsja narjadu s bolee rannimi metodami mechenija jetih i podob- nyh molekul. Sintez jetogo soedinenija, mechennogo tritiem, byl sdelan dlja togo, chtoby polu- chit' radiohimicheskoe chistoe lekarstvo s udel'noj aktivnost'ju v 28 kjuri/mil- limol' (odin atom tritija na molekulu). Budet pokazano, chto jeto soedinenie bystro vhodit v zhivuju kletku kak v este- stvennyh, tak i i laboratornyh uslovijah i chto kul'tury zlokachestvennyh kletok pogloshhajut mechenye atomy v gorazdo bol'shem ob{sup e}me, chem kul'tury normal'nyh kletok pri teh zhe uslovijah. Budut opisany predvaritel'nye issledovanija primenenija jetogo lekarstva na pacientah, imejushhih zlokachestvennye opuholi i nahodjashhihsja v tjazhelom ili neizlechimom sostojanii; usvoenie kostnym na kojefficient 5 mozgom nizhe, chem usvoenie opuhol'ju. (author)

  11. Magnetic nanoparticles for cancer therapy; Nanoparticulas magneticas para o tratamento do cancer

    Bakuzis, Andris F. [Universidade Federal de Goias (UFG), Goiania, GO (Brazil). Instituto de Fisica

    2014-07-01

    Full text: Magnetic nanoparticles have been used in several biomedical applications, spanning from cell separation, early diagnosis of metastasis to even the treatment of cancer via magnetic hyperthermia (MH). This last technique consists in the increase of temperature of nanoparticles when their magnetic moments interact with a magnetic alternating field. This effect has been suggested as an innovative therapy to cancer treatment, due to the delivery of heat or therapeutic agents, such as drugs, genes, and others. In addition, several clinical studies has demonstrated synergetic effects between hyperthermia and radiotherapy [1]. This indicates a great therapeutic potential for this noninvasive and targeted technique. In this talk we will discuss results from the literature and from our own group in the treatment of cancer via magnetic hyperthermia. Several types of magnetic nanoparticles suggested for this application will be discussed, as well as the historical evolution of this procedure, which although suggested in the late 50' only recently was approved in Europe for treatment of humans with brain tumors. (author) [Portuguese] Full text: Nanoparticulas magneticas tem sido utilizadas em diversas aplicacoes biomedicas, desde a separacao de celulas, marcacao de celulas-tronco, diagnostico precoce de metastases ao tratamento do cancer via hipertermia magnetica (HM). Esta ultima tecnica consiste no aumento da temperatura de nanoparticulas quando seus momentos magneticos interagem de forma adequada com um campo magnetico alternado. Este efeito tem sido idealizado como uma nova terapia para o tratamento do cancro, seja via entrega seletiva de calor ou mesmo pela liberacao de farmacos, genes ou outros agentes terapeuticos por meio desta acao externa. Adicionalmente, diversos estudos clinicos tem demonstrado efeitos sinergicos entre a hipertermia e tecnicas tradicionais de tratamento oncologico, como quimioterapia e radioterapia. Isto indica um forte potencial

  12. Oncogenes, radiation and cancer; Oncogenes, radiacion y cancer

    Michelin, S C

    1999-12-31

    The discovery of the oncogenic virus and the analysis of its nucleic acid, together with the development of new biochemical technology have permitted the partial knowledge of the molecular mechanisms responsible for the cellular neoplastic transformation. This work, besides describing the discovery of the first oncogenic virus and the experiments to demonstrate the existence of the oncogenes, summarizes its activation mechanisms and its intervention in cellular metabolisms. Ionizing radiation is among the external agents that induce the neoplastic process. Its participation in the genesis of this process and the contribution of oncogenes to the cellular radioresistance are among the topics, which are referred to another topic that makes reference. At the same time as the advancement of theoretical knowledge, lines of investigation for the application of the new concepts in diagnosis, prognosis and therapeutical treatment, were developed. An example of this, is the study of the participation of the oncogen c-erbB-2 in human breast cancer and its implications on the anti tumoral therapy. (author) 87 refs., 7 figs., 3 tabs. [Espanol] El descubrimiento de los virus oncogenicos y el analisis de su acido nucleico, junto con el desarrollo de nuevas tecnicas bioquimicas, ha permitido conocer parcialmente los mecanismos moleculares responsables de la transformacion de una celula normal en neoplasica. En este trabajo, ademas de describir el descubrimiento de los primeros virus oncogenicos y las experiencias para demostrar la existencia de los oncogenes, se resumen sus mecanismos de activacion y su intervencion en el metabolismo celular. Entre los agentes expernos que inducen un proceso oncogenico, se encuentran las radiaciones ionizantes. Su participacion en la genesis de este proceso y la contribucion de los oncogenes a la radioresistencia de las celulas tumorales, es otro de los temas a que se hace referencia. Paralelamente al avance del conocimiento teorico, se

  13. Modeling and simulation of PEM fuel cell's flow channels using CFD techniques

    Cunha, Edgar F.; Andrade, Alexandre B.; Robalinho, Eric; Bejarano, Martha L.M.; Linardi, Marcelo; Cekinski, Efraim

    2007-01-01

    Fuel cells are one of the most important devices to obtain electrical energy from hydrogen. The Proton Exchange Membrane Fuel Cell (PEMFC) consists of two important parts: the Membrane Electrode Assembly (MEA), where the reactions occur, and the flow field plates. The plates have many functions in a fuel cell: distribute reactant gases (hydrogen and air or oxygen), conduct electrical current, remove heat and water from the electrodes and make the cell robust. The cost of the bipolar plates corresponds up to 45% of the total stack costs. The Computational Fluid Dynamic (CFD) is a very useful tool to simulate hydrogen and oxygen gases flow channels, to reduce the costs of bipolar plates production and to optimize mass transport. Two types of flow channels were studied. The first type was a commercial plate by ELECTROCELL and the other was entirely projected at Programa de Celula a Combustivel (IPEN/CNEN-SP) and the experimental data were compared with modelling results. Optimum values for each set of variables were obtained and the models verification was carried out in order to show the feasibility of this technique to improve fuel cell efficiency. (author)

  14. Modeling and simulation of PEM fuel cell's flow channels using CFD techniques

    Cunha, Edgar F.; Andrade, Alexandre B.; Robalinho, Eric; Bejarano, Martha L.M.; Linardi, Marcelo [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)]. E-mails: efcunha@ipen.br; abodart@ipen.br; eric@ipen.br; mmora@ipen.br; mlinardi@ipen.br; Cekinski, Efraim [Instituto de Pesquisas Tecnologicas (IPT-SP), Sao Paulo, SP (Brazil)]. E-mail: cekinski@ipt.br

    2007-07-01

    Fuel cells are one of the most important devices to obtain electrical energy from hydrogen. The Proton Exchange Membrane Fuel Cell (PEMFC) consists of two important parts: the Membrane Electrode Assembly (MEA), where the reactions occur, and the flow field plates. The plates have many functions in a fuel cell: distribute reactant gases (hydrogen and air or oxygen), conduct electrical current, remove heat and water from the electrodes and make the cell robust. The cost of the bipolar plates corresponds up to 45% of the total stack costs. The Computational Fluid Dynamic (CFD) is a very useful tool to simulate hydrogen and oxygen gases flow channels, to reduce the costs of bipolar plates production and to optimize mass transport. Two types of flow channels were studied. The first type was a commercial plate by ELECTROCELL and the other was entirely projected at Programa de Celula a Combustivel (IPEN/CNEN-SP) and the experimental data were compared with modelling results. Optimum values for each set of variables were obtained and the models verification was carried out in order to show the feasibility of this technique to improve fuel cell efficiency. (author)

  15. Formalization of common power and efficiency definitions for energy-converting intracellular biochemical processes

    Santillan, M.; Angulo-Brown, F.; Chavoya-Aceves, O. [Instituto Politecnico Nacional, Mexico, D. F. (Mexico)

    2001-04-01

    The definitions of power and efficiency for energy-converting intracellular biochemical processes, introduced by Caplan and Essig are studied. These definitions are recovered in the present work with the formalism of De Groot and Mazure for First-Order Irreversible Thermodynamics, rather than the formalism of Prigogine, as done by Caplan and Essig. The approach here employed permits to keep track of all the assumptions in a more clear manner, and to get rid of a very strong restriction in the approach of Caplan and Essig which assumes that the chemical potentials are homogeneous inside the cell. [Spanish] Se estudian las definiciones de potencia y eficiencia para procesos bioquimicos intracelulares convertidores de energia, introducidas por Caplan y Essig. En el presente trabajo, dichas definiciones se recuperan usando el formalismo de De Groot y Mazur para la termodinamica irreversible de primer orden, en vez del formalismo de Prigogine, empleado por Caplan y Essig. El punto de vista empleado en el presente manuscrito permite seguir las suposiciones hechas de una manera mas clara, ademas de que hace innecesaria una suposicion bastante fuerte usada por Caplan y Essig, la cual da por hecho que los potenciales quimicos son homogeneos en el interior de la celula.

  16. Neuropatía Endémica Crónica Asociada con Virus Humano Linfotrófico

    Jaime G. Gómez

    1990-04-01

    Full Text Available

    Diagnóstico y Tratamiento de la Neuropatía Endémica Crónica Asociada con Virus Humano Linfotrófico de Células T, Tipo I (HTLV-l

    El propósito del presente artículo es haccr una breve revisión del estado actual de la Neuropatía endémica crónica asociada con el Virus Humano Linfotrópico de Celulas T-tipo L conocido por la sigla inglesa HTLV-I y presentar el primer caso tratado con éxito. logrando posiblemente la curación de la enfermedad.

    La Neuropatía endémica asociada con el Virus Humano Linfotrópico de Celulas T-tipo 1, (NEC-HTL V-1 es una enfermedad lentamente progresiva caracterizada por debilidad de las extremidades inferiores, trastornos de los esfínteres, alteraciones subjetivas de la sensibilidad, asociadas con la presencia de anticuerpos contra el HTL V-I en la sangre y en el líquido cefalorraquídeo.

    La enfermedad fue descrita por primera vez hace casi cien años en Jamaica por Strachnan (1897, Cruishank publicó en 1956 el cuadro patológico en el cual se encuentra degeneración de las vías piramidales, desmielinización, proliferación capilar con acúmulos de linfocitos alrededor de los vasos sanguineos. Maní y col informaron una enfermedad similar en el Sur de la India (1969. En 1981 Zaninovich encontró una zona endémica en la costa del Pacífico de Colombia y gracias a su interes consiguió apoyo de la Organización Mundial de la Salud y del Instituto Nacional de Salud de los Estados Unidos para adelantar los estudios sobre esta endemia.

    En 1985 Gessain y col hallaron por primera vez en Martinfca anticuerpos contra el HTL V-1 en una alta proporción de pacientes con la enfermedad que denominaron Paraparesia Espástica Tropical.

    El Virus Humano Linfotrópico de Celulas T o HTL V-1, pertenece a la familia de los Retrovirus, caracterizados por poseer una enzima denominada Transcriptasa Invertida (“Reverse Transcriptase”. Fue descubierto por Gallo

  17. Criopreservação de formas de cultura do Trypanosoma cruzi Cryopreservation of Trypanosoma cruzi culture form

    Lúcia Maria C. Galvão

    1981-09-01

    Full Text Available Formas de cultura de diferentes cepas do T.cruzi foram submetidas a vários processos de criopreservação. As percentagens de recuperação, avaliadas pela motilidade dos parasitas, foram consideradas como adequadas com algumas das técnicas empregadas, variando entre 60 a 80%. A estabilidade das características biológicas do material criopreservado foi investigada através do estudo das curvas de crescimento e diferenciação em meio acelular, infectividade para celulas de cultura de tecido ("Vero", diferenciação intracelular em cultura de tecido assim como infectividade e curso da infecção em animais de laboratório. De um modo geral essas características nao foram significativamente alteradas no material congelado e estocado por diferentes períodos de tempo.A systematic study of the cryopreservation of T. cruzi culture forms was per formed using different parasite strains and freezing methods. The recovery rates with some of the methods as evaluated by motility of the thawed parasites were fairly high (60-80%. The following aspects have been used to investigate the stability of the parasites' biological characteristics atter cryopreservation: growth and differentiation in acelular medium, infectivity to tissue culture "Vero" cells, intracellular differentiation and infectivity to animals. Those characteristics had not been significantly changed by the cryopreservation procedures.

  18. La célula de Schwann

    Adriana del Pilar López Lombana

    1993-12-01

    Full Text Available La célula de Schwann que constituye la glía del SNP, además de ser el soporte estructural para los axones en dicho sistema, tiene la función de producir la mielina, una organela de gran importancia en los procesos de neuroconducción. De la integridad de esta célula dependen el desarrollo estructural y metabólico del axón, así mismo se ha reconocido desde hace varios anos el papel primordial que juega ella, en los procesos de regeneración del SPN posterior a una injuria, en cuyo caso reinician la proliferación para producir una guía de regeneración del nervio periférico. En esta revisión se contemplarán algunos de los puntos relacionados con su origen, desarrollo, estructura, relación con el axon y el tipo de patologías que pueden alterarla; igualmente se resalta la utilidad de los cultivos de celulas de Schwann para el estudio de los procesos de mielinización, desmielinización, regeneración post-traumatica y respuesta a agentes infecciosos.

  19. Algumas investigações sobre Schizotrypanum de Quirópteros

    Emmanuel Dias

    1939-01-01

    Full Text Available Os autores referem as especies de morcegos de diversos países americanos, emque foi pesquisada no sangue a presença de hemoflagelados. Tripanosomas com a morfologia das formas sanguicolas de Schizotrypanum foram encontrados, tendo sido colhidos dados novos sobre a distribuição geografica e a incidencia da infecção em diferentes especies de morcegos. Sómente nos tecidos do Phyllostomus hastatus puderam ser encontradas as formas de multiplicação do flagelado. Alimentando-se exemplares de Triatoma infestans em Eumops bonariensis beckeri infectado, foi obtido desenvolvimento intestinal do parasito. Por inoculação das vinchucas assim infectadas em camondongo, conseguiu-se facilmente transmissão da infecção a este animal. Inoculando-se cultura do Schizotrypanum de Phyllostomus hastatus em coelho, por via subcutanea, verificaram-se no ponto de inoculação, 5 dias depois, celulas contendo tipicas formas de leishmania. São assinalados fatos observados sobre a associação demorcegos com Hemipteros sugadores (Reduvideos e Cimicideos, os quais, pela circunstancia de se poderem infectar pelo flagelado, são os possiveis transmissores da infecção a estes mamiferos.

  20. Linfoma primario del sistema nervioso central en una paciente con lupus eritematoso sistémico

    C. N. Pisoni

    2003-06-01

    Full Text Available Se presenta una paciente de 36 años con diagnóstico de lupus eritematoso sistémico tratada con prednisona y ciclofosfamida que se internó por cefalea, hemiparesia y hemianestesia braquiocrural derecha de dos semanas de evolución. Se realizó una tomografía computada y una resonancia magnética nuclear de cerebro que mostraron una lesión nodular frontal izquierda. Se efectuó una biopsia a cielo abierto de la lesión cerebral cuyo diagnóstico histopatológico fue linfoma B de celulas grandes, difuso. Se inició radioterapia, no completó el tratamiento por complicaciones y falleció. Son muy pocos los casos publicados de linfoma primario del sistema nervioso central asociado a lupus eritematoso sistémico.A 36 year-old woman with systemic lupus erythematosus was admitted to our hospital with headache, brachiocrural hemiparesis and hemianesthesia. She had been treated with prednisone and cyclophosphamide. CT scan and MRI revealed a 15 mm nodular mass enhanced with gadolinium in left frontal convexity. CNS biopsy was performed and a diffuse large B-cell lymphoma was diagnosed. She was treated with radiation therapy without response and died. There are few reports of erythematosus systemic lupus associated with primary central nervous system lymphoma.

  1. Las histiocitosis Histiocytosis

    Eva Svarch

    2001-12-01

    Full Text Available El término histiocitosis identifica un grupo de alteraciones que tienen en común la proliferación de células dendríticas (CD y los macrófagos, y se diagnostican más frecuentemente en niños. Dentro de las relacionadas con las CD las fundamentales son las histiocitosis a células de Langerhans (HCL. Las HCL tienen un comportamiento clínico muy variable, que puede ir desde una lesión que involucra un solo sitio o sistema hasta una enfermedad multisistémica. El tratamiento depende de la extensión del proceso. Una lesión única tiende a desaparecer espontáneamente. También la biopsia diagnóstica con o sin inyección de un esteroide puede iniciar la curación. Los pacientes con enfermedad multisistémica pueden beneficiarse con el tratamiento esteroideo y citostático o inclusive con el trasplante de células progenitoras hematopoyéticas. La histiocitosis sinusal con linfoadenopatías masivas o enfermedad de Rosai Dorfman se debe a la proliferación de los macrófagos, es de naturaleza benigna y usualmente autolimitada. Afecta sobre todo a niños y adultos jóvenes. La linfohistiocitosis hemofagocítica también se produce por la proliferación de los macrófagos y es una enfermedad rara con una alta mortalidad. Puede ser familiar (autosómica recesiva o secundaria a infecciones virales. Esta última forma se presenta más frecuentemente en el lactante pequeño. En la actualidad, sobre todo en la variedad familiar, el trasplante alogénico de células progenitoras hematopoyéticas puede ser la única medida curativaThe term histiocytosis identifies a group of disorders that have in common the proliferation of dentritic cells (DC and macrophages and is frequently diagnosed in children. Among the fundamental variants of histiocytosis related with DC, we find Langerhans cell histiocytosis (LCH. Langerhans cell histiocytosis has very variable clinical behavior that ranges from a lesion involving only one site or system to a multisystem

  2. Effect of {alpha}-Particle and X-Ray Irradiation on DNA Synthesis in Tissue Cultures; Effet de l'Irradiation par les Particules a et par les Rayons X sur la Synthese de l'ADN dans des Cultures de Tissus; 0412 043b 0438 044f 0414 ; Efectos de la Irradiacion con Particulas Alfa y con Rayos X sobre la Sintesis de ADN en Cultivos de Tejidos

    Smith, C. L. [Department of Radiotherapeutics, University of Cambridge, Cambridge (United Kingdom)

    1962-02-15

    lesions subies par la structure type de l'ADN (ou du phosphate de l'ADN) pendant la phase exponentielle dela synthese, les observations formulees plus haut sous 1, 2 et 3 constituent les corollaires evidents de ce phenomene. (author) [Spanish] La memoria describe los efectos de las particulas {alpha} y de los rayos X sobre la velocidad de sintesis del ADN en cultivos de tejidos de fibroblastos y de celulas de HeLa del raton. Los autores emplearon el metodo de la microautorradiografia con timidina tritiada, que les permitio evaluar la velocidad de sintesis en los cultivos de una sola capa que utilizaron. Los resultados indican que: 1) La fraccion de celulas que sintetizan ADN en un cultivo no es alterada por las particulas a. ni por los rayos X en las dosis experimentales empleadas. 2) Ambos tipos de radiaciones reducen la velocidad de sintesis del ADN en las celulas irradiadas. 3) El efecto de una dosis determinada de cualquiera de las dos radiaciones es disminuir la velocidad de sintesis de todas las celulas hasta una fraccion constante de la velocidad correspondiente a las celulas no irradiadas. 4) En. el caso de los fibroblastos del raton, la velocidad de sintesis del ADN queda reducida en un 37 por ciento (1/e) por una dosis a del orden de 25 {alpha}/{mu}{sup 2} o por una dosis de rayos X de 14 000 rad( En el caso de las celulas de HeLa, se requiere una dosis de unos 90 000 rad para alcanzar el mismo efecto. 5) La disminucion de la velocidad de sintesis se produce menos de media hora despues de la irradiacion, por lo que podria tratarse de un efecto inmediato. El resultado 4) permite calcular aproximadamente la forma del blanco. Si seo supone que es cilindrico, enoel caso de los fibroblastos, tendria un diametro aproximado de 16 A y una longitud de 16 000 A, es decir, se trataria de un cilindro extremadamente alargado con un peso molecular del orden de 5 x 10{sup 7}. Para las celulas de HeLa se obtendria un peso molecular de 10{sup 7}. Los resultados concuerdan con la

  3. Incidencia de neoplasias hematológicas en el Área Metropolitana de Bucaramanga, 2000-2004

    Claudia Janeth Uribe Pérez

    2008-07-01

    Full Text Available Resumen SummaryAntecedentes: Las lesiones hematooncológicas son un grupo de neoplasias generadas por alteraciones células progenitoras hematopoyéticas. Este tipo de lesiones afectan a la población en general, con un porcentaje importante de ocurrencia en la población infantil. En el Área Metropolitana de Bucaramanga (AMB estos trastornos se ubican dentro de las lesiones malignas más frecuentes region (2000 - 2004. Metodología: El Registro Poblacional del AMB realiza un proceso de búsqueda y verificación IACR, activa de los casos de cáncer en la población residente AMB desde el 2000. Luego de los procesos de validación, los casos son codificados y digitados en CanReg-4 con el cual se estiman frecuencias y tasas de software. Este informe tiene datos verificados y actualizados que incluyen los obtenidos en el proceso de validación de egreso hospitalario y registros de mortalidad. Resultados: Entre 2000 y 2004 se captaron 620 casos de neoplasias hematolinfoides ubicándose en los primeros lugares tanto en hombres como en mujeres, con un mayor número de casos en los hombres especialmente por casos de leucemia linfoide. Se encuentra tasa cruda de 10.9 casos Conclusión: Comparando con las cifras del proyecto , el comportamiento de las neoplasias hematológicas en esta región es similar a lo estimado para el Área Metropolitana de Bucaramanga

  4. Características florais e carpométricas e germinação in vitro de grãos de pólen de cultivares de amoreira‑preta

    Madeleine Alves de Figueiredo

    2013-07-01

    Full Text Available O objetivo deste trabalho foi avaliar as características florais e carpométricas, a viabilidade dos grãos de pólen e a capacidade germinativa de sementes de cultivares de amoreira‑preta. Foram avaliadas as cultivares Brazos, Caingangue, Cherokee, Choctaw, Comanche, Guarani, BRS Tupy e Ébano. Utilizou-se um delineamento experimental inteiramente casualizado com as oito cultivares e dez repetições. Foram feitas avaliações quanto a: número de estames, carpelos, pétalas e sépalas; composição do meio de cultura; número de grãos de pólen por antera e por flor; taxa de germinação de grãos de pólen; percentagem de frutificação; massa de matéria fresca, dimensões e número de sementes dos frutos; massa e dimensões dos drupetes; e percentagem de emergência de plântulas. O meio de cultura estabelecido para as cultivares de amoreira‑preta foi acrescido de 90 g L‑1 de sacarose e 400 mg L‑1 de ácido bórico, com pH aferido para 6,5 e meio solidificado com 8 g L‑1 de ágar. 'Caingangue', 'Ébano' e 'BRS Tupy' apresentaram baixa germinação de grãos de pólen. 'Ébano' apresentou frutos arredondados e com poucos drupetes. 'Choctaw' e 'Comanche' apresentaram baixa percentagem de emergência de plântulas. 'Brazos' destacou-se na maioria das características avaliadas e é considerada como boa progenitora para programas de melhoramento genético.

  5. Avanços tecnológicos em hematologia laboratorial Technological advances in laboratorial haematology

    Paulo C. Naoum

    2001-08-01

    Full Text Available O recente avanço científico e tecnológico direcionado à identificação imuno-hematológica de produtos celulares (ex.: citocinas, interleucinas, interferons, entre outros sintetizados por determinadas células sanguíneas, bem como na identificação de antígenos de membrana de leucócitos e células progenitoras hematopoiéticas, promoveram excepcional desenvolvimento no diagnóstico laboratorial de diversas doenças hematológicas. Somam-se a esse fato as aplicações das técnicas de biologia molecular que se tornam cada vez mais instrumentos laboratoriais de grande definição no diagnóstico e na prevenção de doenças hematológicas, notadamente aquelas de origem hereditária. O presente artigo teve o objetivo de expor as principais aplicações de novas tecnologias que deverão ser adotadas rapidamente pela moderna hematologia laboratorial, bem como a de sensibilizar os profissionais hematologistas, clínicos e laboratoriais, para a necessidade de se atualizarem numa nova ciência, a dos produtos celulares.Recent progress towards the identification of products synthesised by some blood cells (ex.: cytokines, interleukins, interferons, etc as well as the identification of white blood cell and stem cell membrane antigens, has aided the exceptional development of laboratory diagnostics of several haematological diseases. In addition to this there has been a great development in the use of molecular biology techniques which have become instrumentals of high definition in the diagnosis and prevention of haematological diseases, specifically those of hereditary origin. This article has the aim of disclosing the main applications of the new technologies that will soon be used widely in laboratory haematology.

  6. Influência do estiolamento e do ácido indolebutírico na formação de raízes do alporque de cajueiro Anão Precoce (Anacardium Occidentale L.

    Francisco Célio Guedes Almeida

    1990-01-01

    Full Text Available O cajueiro é uma planta geralmente propagada por semente. Sua multiplicação vegetativa ainda não é comercialmente viável. Neste estudo os efeitos do estiolamento e do ácido indolebutírico (AIB na formação de raízes do alporque da planta de caju foram investigados. O estiolamento foi realizado 30 dias antes do início do processo de alporquia. Por ocasião do anelamento do ramo, o AIB foi aplicado. Após 30 dias da realização da alporquia, os ramos já enraizados foram removidos da planta progenitora. Em seguida foram colocados em saco plástico na casa de vegetação sob condições de irrigação intermitente. Os resultados sugeriram um prévio estiolamento do ramo antes do processo de alporquia e uma aplicação de AIB, por ocasião do anelamento para, garantir a sobrevivência do alporque após o desmame.The Cashew tree is usually propagated by seed since vegetative multiplication has not been fully satisfactory. In this work the effects of etiolation and AIB on air layered branches of the cashew tree were studied. Previous to airlayering procedure, the branches were etiolated during 30 days. The AIB was applied when the bark of the stem was cut. After 30 days the layers were removed from the parent plant at which roots stage were observed through the transparent bag. The rooted layers were planted in polyethylene bags and placed in a greenhouse under an intermitent-mist water spray condition. The results show that the previous etiolation and application of AIB to the exposed wound were beneficial to increase rooting and survival of cashew air layers.

  7. Transplante de células tronco hematopoéticas para doenças auto-imunes no Brasil Hematopoietic stem cell transplantation for autoimmune diseases in Brazil

    Júlio C. Voltarelli

    2002-03-01

    Full Text Available O transplante de células progenitoras hematopoéticas apresenta bases sólidas para ser indicado no tratamento das doenças autoimunes. No relato são apresentados estes dados e a seqüência de eventos que tem contribuído para a implantação de um protocolo brasileiro do procedimento na modalidade autogênica utilizando regimes de mobilização uniforme com Ciclofosfamida 2g/m2 mais fator estimulador de colônias granulocitárias e condicionamentos particulares para o lúpus eritematoso sistêmico, esclerose sistêmica e esclerose múltipla. As entidades descritas anteriormente foram escolhidas para o início do protocolo cooperativo após amplos debates em encontros ocorridos em Ribeirão Preto e São Francisco, EUA.Hematopoietic Stem Cell Transplantation presents a solid basis to be indicated for the treatment of autoimmune diseases. In this work data related to the procedure and the sequence of events which have contributed to the implantation of a Brazilian protocol are discussed. Included is a discussion of the autogenic procedure using uniform mobilization regimens with Cyclophosphamide 2g/m2 plus granulocyte-colony stimulation factor and particular conditioning for systemic lupus erythematosus, systemic sclerosis and multiple sclerosis. The formerly described entities were chosen for the beginning of a cooperative protocol after wide-ranging debates which took place both in Ribeirão Preto and San Francisco, USA.

  8. La modalidad de agentes multiplicadores para orientar a madres y padres de familia

    Cecilia Villarreal Montoya

    2014-01-01

    Full Text Available Recibido 9 de abril de 2013 • Corregido 22 de agosto de 2013 • Aceptado 11 de setiembre de 2013 En este artículo se sistematiza una experiencia de orientación con madres y padres de familia en instituciones educativas de las provincias de San José y Heredia, Costa Rica. La modalidad de “agentes multiplicadores” fue la estrategia utilizada en el proyecto de extensión “Fortalecimiento de la familia” de la División de Educación para el Trabajo (DET de la Universidad Nacional. Un grupo de profesionales de la orientación y docentes de esta División, capacitó como facilitadoras a un grupo de dieciocho profesionales, tanto de la orientación como de otras disciplinas, en comunicación familiar, en la expresión del enojo, la cosmovisión de las familias, y la planificación de proyectos para trabajar con madres y padres de familia con una metodología participativa, en la cual se tomaron, como insumo, las vivencias de quienes participan en los proyectos de orientación familiar. Los proyectos se pusieron en práctica en nueve instituciones y participaron en total ciento cinco madres y seis padres de familia. En el apartado que resume los logros obtenidos se destaca el impacto del salto metodológico al cambiar “la charla” por la participación de madres y padres con sus propias experiencias vitales en la convivencia familiar. Los aprendizajes obtenidos han sido insumos de utilidad en la ampliación y continuación de este proyecto dirigido a la orientación de figuras progenitoras.

  9. Quantificação de células CD 34+ em sangue periférico, produto de aférese e cordão umbilical: estudo comparativo de três diferentes metodologias

    Bacal Nydia S.

    2001-01-01

    Full Text Available A quantificação das células CD34+ em sangue periférico é utilizada para determinar o melhor momento de iniciar a aférese, enquanto que na leucoaférese e no sangue de cordão umbilical determinam a quantidade de células CD34+ para o transplante de células progenitoras. O objetivo deste trabalho foi comparar três diferentes metodologias de quantificação de células CD34+. Foram utilizados três diferentes tipos de amostras: a 32 amostras de sangue periférico, coletadas de pacientes estimulados com G-CSF 50 mg/Kg/dose total, sem quimioterapia na mobilização. b 31 amostras de produto de aférese de pacientes estimulados com o mesmo protocolo de G-CSF. c 20 amostras de sangue de cordão coletadas em CPDA-1, por punção de veia umbilical. As amostras permaneceram à temperatura ambiente no máximo até 24h da análise. O citômetro de fluxo utilizado foi o Epics XL-MCL (Coulter com os protocolos de dupla plataforma: ISHAGE e Mulhouse modificado para análise de maior numero de eventos, e o citômetro Imagn 2000 (Biometric Imaging de plataforma única, conforme técnicas recomendadas. Os anticorpos monoclonais utilizados foram: CD45-FITC, CD34-PE, e isotipo IgG1-PE da Immunotech. As análises estatísticas foram: ANOVA e correlação de teste t de Student. Os resultados não apresentaram diferenças estatisticamente significativas nos três métodos.

  10. Líneas de girasol de la EEA Pergamino

    GONZÁLEZ, J

    2011-04-01

    Full Text Available Se analizaron tres grupos de líneas de girasol (Helianthus annuus de la EEA Pergamino del INTA. Grupo 1: líneas derivadas de los compuestos P1, P2, P4, PGRK y KLM liberadas en la década del 90. Grupo 2: líneas GP logradas de cruzas entre las del grupo 1 con otras fuentes, liberadas a partir del 2001. Grupo 3: líneas AO (contenido de oleico > 80% derivadas de materiales del North Dakota y de cruzas con materiales locales. Se analizaron los siguientes caracteres: número de aquenios por capítulo, peso de cien aquenios, porcentaje de pepita y aceite, altura de planta y número de días desde siembra a floración. El objetivo fue evaluar la variabilidad del germoplasma entre grupos y las asociaciones entre caracteres dentro de cada grupo, para identificar el idiotipo y las características diferenciales. El efecto de la selección se manifestó claramente al comparar los grupos. En el Grupo 1, la selección se efectuó principalmente por rendimiento de semilla y en los Grupos 2 y 3, se dirigió a la mejora del contenido porcentual de aceite y contenido porcentual de oleico respectivamente. Las líneas del Grupo 2 y Grupo 3 (AO superaron en contenido de aceite a las del Grupo 1, las cuales fueron de mayor altura y peso de aquenio. Dentro de cada grupo se identificaron de 4 a 6 subgrupos caracterizados por los objetivos del mejoramiento y diferenciándose líneas independientes derivadas por objetivos de selección indirecta. El germoplasma evaluado podría incorporarse a diferentes “backgrounds” genéticos según los objetivos del mejoramiento.

  11. 182. Cirugía de preservación de válvula aórtica

    D. Valencia Núñez

    2012-04-01

    Conclusión: En nuestra experiencia, la preservación de la válvula aórtica con reimplante valvular o remodelación de la raíz aórtica ha mostrado unos resultados excelentes. Evita las complicaciones tromboembólicas y hemorrágicas derivadas de las prótesis y de la anticoagulación crónica, proporcionando unos resultados hemodinámicos y una calidad de vida excelentes.

  12. Sobre la aplicación del método de entropía en el estudio de soluciones globales en tiempo de ecuaciones diferenciales de evolución de tipo parabólico

    Langoni, Laura

    2011-01-01

    Es un hecho conocido la creciente importancia y el amplio campo de aplicación que las ecuaciones en derivadas parciales tienen en la construcción de modelos matemáticos para la descripción de una gran variedad de problemas provenientes de diversas áreas del saber como, por ejemplo, la economía, la física, la biología. Muchos procesos de las ciencias aplicadas se pueden modelar matemáticamente por medio de ecuaciones de evolución. Estas ecuaciones, llamadas ecuaciones de estado, desc...

  13. Disponibilidades hídricas para la forestación en el Valle de Calamuchita, Córdoba

    Ravelo, Andrés Carlos; Zanvettor, R. E.; Ingaramo, P.

    1997-01-01

    p.111-116 Las disponibilidades hídricas para la forestación con Pinus elliottii y Pinus taeda en el valle de Calamuchita fueron analizadas utilizando el balance hídrico del suelo. Las similitudes de variables derivadas del balance hidrico para localidades del valle y localidades de origen de ambas especies indica condiciones adecuadas para el desarrollo de dichas especies. Mediante un análisis numérico de agregación se identifican a localidades del lugar de origen como posibles fuentes pro...

  14. Involvement of integrins in the adhesion of osteoblastic cells to a type-I collagen matrix

    Antonio Desmond McCarthy; Toshimasa Uemura; Susana Beatriz Etcheverry; Ana María Cortizo

    2006-01-01

    Se han desarrollado varios biomateriales con potencial aplicaci ón en la reconstrucción de tejidos. En este sentido, existe un creciente interés en el diseño de materiales de implante óseo con máxima biocompatibilidad y adecuada adhesividad celular. El objetivo de este trabajo fue estudiar cuáles receptores integrinas participan en la adhesión de osteoblastos a una matriz de colágeno tipo-I. Se analizaron dos líneas celulares osteoblásticas: UMR106, derivada de osteosarcoma de rata; y MC3T3E1...

  15. Masonería y Sociabilidad en el centro y sur de la campaña bonaerense: Fines del siglo XIX principios del XX

    Yolanda de Paz Trueba

    2011-01-01

    El objetivo de este trabajo es reflexionar en torno a la relación establecida entre la sociabilidad política derivada de la influencia masónica y otras formas de sociabilidad previas ligadas al catolicismo, en el marco de la construcción del Estado en sus diversos niveles a fines del siglo XIX. Este abordaje será realizado a través del análisis de pueblos de la campaña bonaerense, espacios no estudiados en este sentido hasta el momento.

  16. Gestalt y aprendizaje / Gestalt and learning

    Fallas Vargas, Fabrizio

    2008-01-01

    Resumen: El presente trabajo explora las principales implicaciones de la teoría Gestalt en tanto que modelo de aprendizaje. Para ello desarrolla las categorías de análisis fundamental producidas por sus exponentes fundadores, Wertheimer, Koffka, y Köhler, el concepto de pensamiento productivo, así como las reglas perceptuales derivadas de sus investigaciones empíricas. Asimismo se exploran aplicaciones pedagógicas y psicopedagógicas de la teoría, en articulación con el concepto axial de la Ge...

  17. Estudio de la calidad en la entrega de las obras de vivienda en la República Dominicana

    Leguisamón Reyes, Francis Almanzor

    2012-01-01

    Una vez entregada una obra se supone que ha pasado todos los controles de calidad y no hay defectos. En realidad, una vez entregada la obra, se constata que las reclamaciones y quejas de los usuarios finales son numerosas. La mayorías de estas reclamaciones vienen derivadas por defectos en paredes y recubrimientos, omisiones de elementos vinculados a las instalaciones y errores en el mobiliario. Este proyecto pretende, a partir de los datos de reclamaciones de los usuarios finales y de datos ...

  18. La influencia de la música popular en la sociedad contemporánea desde la segunda mitad del siglo XX: Aplicación a la enseñanza de la historia en la Eso y el bachillerato

    Molero Gómez, Ismael

    2015-01-01

    Este estudio trata de profundizar a través del rock ‘n’ roll (como aglutinador de otras expresiones musicales) y las especiales condiciones en las que surge tanto culturales, como sociales e históricas, en el impacto que la música popular y la cultura juvenil derivada de la misma causaron en el modelo de sociedad tradicional, al surgir abruptamente como fenómeno de masas a mediados de los años cincuenta. El objetivo es establecer elementos identitarios de la sociedad contemporá...

  19. El Desarrollo de Valores y Actitudes ético-Morales a través de las Materias Académicas con Implementación Tecnológica: Una Teoría Sustantiva-Edición Única

    Alemán Vargas, Margarita

    2002-01-01

    El tema central del presente estudio es responder cuáles son las implicaciones pedagógicas para la institución escolar laica que busca el desarrollo valores y actitudes éticomorales y utiliza para ello, las materias académicas implantadas bajo un modelo educativo presencial auxiliado por tecnología computacional. Indagar cuáles son las implicaciones derivadas de tal acción educativa conlleva en primer lugar, al análisis de los rediseños instruccionales de las materias académica...

  20. Espumas e cerâmicos densos à base de cordierite: preparação, caracterização e modelação

    Zhang, Lingfei

    2010-01-01

    Os materiais cerâmicos à base de cordierite são normalmente usados como materiais refractários devido às propriedades que possuem, tais como, excelente expansão térmica e elevada resistência ao choque térmico. Os pós precursores consistem numa composição estequeométrica de minerais à base de alumina, talco, α-quartzo, K-feldspato, caolinite e mulite, bem como uma pequena quantidade de calcite, cristobalite e fases vítreas derivadas da moloquite, obtidas pela calcinação da ca...

  1. ¿Teatro épico hoy? Paradojas radicales y tres dramas en español

    García Barrientos, José Luis

    2013-01-01

    [ES] A la luz de las dos paradojas que se advierten en la raíz misma del llamado teatro épico, la política, en cuanto se presenta al servicio de una clase, el proletariado, que no puede sostenerlo, y la narrativa, derivada de la contradicción entre los dos modos de imitación aristotélicos, se defiende la tesis de que en la actualidad siguen plenamente vigentes las aportaciones estéticas (“narrativas”) del teatro épico, pero no el dogmatismo político revolucionario en que supues...

  2. VARIABILIDAD EN LA NOTIFICACIÓN DE REACCIONES ADVERSAS A LAS VACUNAS DE LA GRIPE PANDÉMICA Y ESTACIONAL. TEMPORADAS 2009-2010 Y 2010-2011, COMUNITAT VALENCIANA

    Ana María Alguacil Ramos; José Antonio Lluch Rodrigo; Antonio Portero Alonso; Rosa Martín Ivorra; Eliseo Pastor Villalba

    2012-01-01

    Fundamentos: La pérdida de confianza en la seguridad de las vacunas derivada de situaciones de alarma, como en el caso de la gripe pandémica, puede afectar tanto a las coberturas vacunales como a la sensibilidad frente a la notificación de las sospechas de reacciones adversas asociadas a vacunas (SRAAV). El objetivo del trabajo es describir los efectos adversos a la vacuna frente a la gripe pandémica notificados en la temporada 2009-2010 y comparar si existen diferencias con los descritos con...

  3. Transformación de biomasa en productos de química fina y biocarburantes mediante procesos sostenibles.

    De La Torre Alfaro, Olalla

    2013-01-01

    En los últimos años se han incrementado de manera notable los gases responsables del efecto invernadero que contribuyen al calentamiento global del planeta. Este aumento está estrechamente relacionado con el consumo de materias procedentes de recursos fósiles, es decir, de naturaleza no renovable. La presente tesis doctoral se ha centrado en el diseño de rutas sostenibles para obtener compuestos de interés para la industria a partir de materias primas derivadas de biomasa....

  4. Retos en el cumplimiento del protocolo de Palermo. Estudio de caso: trata de personas con fines de explotación sexual en Colombia

    Arévalo Beltrán, Laura Ximena

    2016-01-01

    El presente estudio de caso tiene como objetivo analizar los retos frente al cumplimiento del Protocolo de Palermo, en materia de explotación sexual, en el Sistema Institucional Colombiano, durante el período comprendido entre los años 2003 y 2014. De manera preliminar se indica que dichos retos son político-jurídicos en cuanto a la manera en la que se cumplen los tratados internacionales, las obligaciones derivadas de ellos y quiénes tienen competencia para desarrollar los mandatos contenido...

  5. La responsabilidad de la televisión mexicana en la erradicación de la violencia de género contra las mujeres y las niñas: apuntes de una investigación diagnóstica

    Vega Montiel, Aimée

    2010-01-01

    Este artículo forma parte de la investigación feminista "La influencia de los medios de comunicación en la representación social de la violencia contra las mujeres y las niñas", y tiene el objetivo de compartir una serie de resultados, análisis y reflexiones preliminares derivadas del análisis de contenido de la programación de los principales canales de televisión abierta en el país, que apuntan a la responsabilidad de esta industria en la erradicación de este problema. This article is pa...

  6. Intoxicación con cocaína: reporte de caso

    Juan Dávila Meneses

    2013-01-01

    El consumo de cocaína en Costa Rica, en cualquiera de sus presentaciones, es un problema creciente de salud pública y seguridad ciudadana desde la década de los 80’s. Las complicaciones derivadas de su uso tienen un impacto considerable en la utilización del recurso humano y económico de nuestro sistema de salud y cuya complejidad de manejo es clara: se ha asociado en forma muy importante con la muerte súbita en pacientes jóvenes y sin factores de riesgo, que presentan infartos agudos del mio...

  7. Avances en Biología Osea: El Osteoclasto

    José Vicente Ballesteros

    1999-10-01

    Full Text Available El osteoclasto es una célula multinucleada encargada de la resorción ósea que tiene una morfología especifica, derivada del sistema hematopoyético que está altamente relacionada con factores locales de crecimiento y con hormonas sistémicas como la PTH, la Calcitonina y la Vitamina D, implicada en la fisiopatología de ciertas entidades como la enfermedad de Paget, la hipercalcemia maligna y la osteoporosis.

  8. Desarrollo competencial en educación infantil a través del aprendizaje basado en proyectos en centros educativos de jaén

    Palomares Ruiz, Pedro

    2017-01-01

    Esta tesis surge derivada de la incertidumbre generada acerca de la idoneidad de la implementación de la práctica pedagógica, aprendizaje basado en proyectos. Tras constatar que a pesar de ser una práctica muy conocida no era proporcional a su grado de implementación suscita el interés por conocer el grado competencial adquirido por el alumnado en el tercer nivel de educación infantil, de los centros de la provincia de Jaén, en los que se ha implementado la práctica pedagógica objeto de estud...

  9. Aplicación web para enseñanza/aprendizaje de cálculo y álgebra

    Almirón García, Adrián

    2015-01-01

    El principal objetivo de este trabajo fin de grado es la implementación de una aplicación web que permita realizar actividades de enseñanza/aprendizaje en las ramas de cálculo y álgebra de las matemáticas, enfocada principalmente en los contenidos impartidos en las asignaturas de matemáticas en Bachillerato, concretamente de la unidad de realización de derivadas. Se han desarrollado dos modelos: Uno para el profesor, que permite la generación de los ejercicios, así como la c...

  10. EQUIPOS VIRTUALES Y ACERTIJOS EN ENTREVISTAS DE TRABAJO. Dos Temas de la Administración Actual

    Guillermo S. Edelberg D.B.A.

    2003-01-01

    Los equipos virtuales han generado una nueva forma del trabajo en equipo. A las ventajas del trabajo en equipo, los equipos virtuales agregan otras derivadas de las características del empleo de moderna tecnología de las comunicaciones. En esta breve nota el autor examina las peculiaridades de un equipo virtual, aporta un conjunto de recomendaciones para la gerencia de estos equipos y establece algunas diferencias básicas entre el trabajo tradicional en equipos y los grupos virtuales. Agrega ...

  11. Construcción de género y estereotipos. Un estudio de las actitudes hacia la diversidad de género

    Isidro, A.I.; Álvarez Reig, E.

    2016-01-01

    Las sociedades patriarcales han usado la categoría sexo/género como medio para la creación de un sistema binario y segregado en el que el hombre ejerce un papel dominante y la mujer es sometida a él. Las desigualdades derivadas de este sistema se ven perpetuadas por la existencia de estereotipos, los cuales alimentan estas desigualdades y limitan el desarrollo de la personalidad. La masculinidad hegemónica instaura un sistema heteronormativo en el que, si bien las mujeres se han visto continu...

  12. Aplicación de técnicas de PCR en tiempo real a la trazabilidad y autenticidad de los piensos

    Pegels Rojas, Nicolette

    2015-01-01

    La trazabilidad y el correcto etiquetado de los piensos y sus ingredientes son factores esenciales para prevenir fraudes y garantizar la seguridad alimentaria. En el ámbito de la lucha contra las Encefalopatías Espongiformes Transmisibles (EETs), la prohibición de la Unión Europea (UE) de alimentar a rumiantes y otros animales de granja con harinas de carne y huesos derivadas de animales, hace necesaria la disponibilidad de metodologías que permitan identificar el origen de las materias prima...

  13. Construcción del análisis real desde el punto de vista de la convexidad

    Sotelo Chico, José Carlos; Sotelo Chico, José Carlos; Sotelo Chico, José Carlos

    2011-01-01

    En el presente trabajo hacemos la construcción del análisis real tomando como pun¬to de partida los conceptos de convexidad, por ejemplo, definimos un intervalo básico, el cual es convexo, que viene a ser un intervalo abierto en la recta real y a partir de este concepto definimos limites, continuidad, derivadas que van de la mano con el concepto de funciones convexas, debemos indicar que estos conceptos se pueden generalizar para espacios de dimensión finita. En el primer capítulo veremos ...

  14. Análisis de la inclusión educativa a través de indicadores de prevalencia de dificultades de aprendizaje, actitudes del profesorado y condiciones de accesibilidad en los centros de la ciudad de Cuenca (Ecuador).

    Vélez Calvo, Ximena

    2017-01-01

    El sistema educativo de Ecuador se encuentra actualmente en un momento de profunda transformación derivada de la reciente aprobación de diferentes leyes nacionales que se han propuesto integrar a este sistema los principios de la educación inclusiva. Formalmente, en Ecuador estas reformas adoptan medidas novedosas que se alinean con las políticas educativas de los sistemas educativos a la vanguardia de la inclusión. Sin embargo, desgraciadamente existe un notable vacío de estudios empíricos q...

  15. USE OF EMBRYONIC STEM CELLS TO TREAT SEVERE EYE DISEASES

    JUSTO AZNAR; JULIO TUDELA

    2016-01-01

    Antecedentes: El uso de células troncales constituye una de las principales posibilidades terapéuticas en el área de la medicina regenerativa. Recientes ensayos clínicos utilizando células derivadas de troncales humanas, muestran resultados esperanzadores, aunque estos deben ser valorados con la necesaria cautela. Discusión: Algunos medios de comunicación han divulgado resultados de estos ensayos sin la debida prudencia, creando quizá expectativas que no se corresponden con...

  16. Tiempos escolares y conciliación: análisis de familias con hijos en Educación Secundaria Obligatoria (12-16 años)

    Fraguela-Vale, Raúl; Lorenzo-Castiñeiras, Juan José; Merelas-Iglesias, Tania; Varela-Garrote, Lara

    2013-01-01

    En  este trabajo se estudia si la conciliación de la vida laboral, familiar y personal se ve afectada por los siguientes factores: contexto sociodemográfico, tiempos escolares y corresponsabilización de las familias en tareas derivadas de la escolarización de sus hijos. Muestra: 859 familias gallegas con hijos en Educación Secundaria Obligatoria (12-16 años), que respondieron a un cuestionario sobre la distribución y uso de su tiempo. Resultados: la conciliación está afectada por el tipo de f...

  17. Historia del paramilitarismo en Colombia

    Rivera,Edgar de Jesús Velásquez

    2007-01-01

    En Colombia, desde la década de los años ochenta del siglo XX tomó fuerza el paramilitarismo como estrategia contrainsurgente, política que no ha sido reconocida como tal por parte de los distintos gobiernos y se expresa como terrorismo de Estado. Incidió en el surgimiento de tal fenómeno, la ideología anticomunista que profesan la mayoría de miembros de las fuerzas armadas, la cultura política derivada de la violencia, la corrupción y el clientelismo, así como el narcotráfico, al igual que l...

  18. C??lulas madre en terapia celular card??aca

    Lobo Gonz??lez, Manuel

    2013-01-01

    La enfermedad cardiovascular, y su frecuente resultado final, el fallo card??aco del ventr??culo izquierdo, son la principal causa de morbimortalidad en los pa??ses desarrollados. La investigaci??n con c??lulas madre podr??a regenerar una variedad de c??lulas que incluye a los cardiomiocitos. Se han utilizado diferentes fuentes celulares para la terapia regenerativa card??aca, incluyendo c??lulas madre card??acas, mioblastos de m??sculo esquel??tico, c??lulas madre derivadas de la...

  19. Metodología sobre obtención de muestra, cultivo y caracterización in vitro de células madre mesenquimales humanas obtenidas de la pulpa de dientes permanentes. Revisión narrativa de la literatura

    Perdomo Díaz, Alexandra

    2014-01-01

    La tendencia actual en la ingeniería de tejidos es el empleo de las células madre mesenquimales (MSCs) aisladas de tejidos adultos, hay un gran interés en el uso de células madre de la pulpa dental (DPSCs) para la regeneración del tejido dental. Por ello, el propósito de este estudio fue realizar una revisión narrativa de la literatura científica disponible para la obtención de muestra, aislamiento y caracterización in vitro de células madre (SCs) mesenquimales derivadas de la ...

  20. Riesgo químico laboral: elementos para un diagnóstico en España

    Alfonso A. Calera Rubio; José María Roel Valdés; Amparo Casal Lareo; Rafael Gadea Merino; Fernando Rodrigo Cencillo

    2005-01-01

    Fundamento: La falta de información junto a la ausencia de un conocimiento preciso de las propiedades intrínsecas de cada agente químico y de la exposición derivada de un uso concreto dificultan en gran medida la prevención de los trabajadores expuestos a los riesgos generados por la presencia de estos productos en los puestos de trabajo. El objetivo del presente estudio es identificar los elementos que permitan efectuar un diagnóstico de la situación del riesgo químico e...

  1. Procesiones, rogativas, conjuros y exorcismos : el campo valenciano ante la plaga de langosta de 1756

    Alberola-Romá, Armando

    2003-01-01

    Entre los años 1756-1758 una plaga de langosta devastó los campos valencianos y los de buena parte de la geografía peninsular. Sus consecuencias alcanzaron enorme relevancia en el antiguo reino de Valencia al coincidir, además, con una meteorología adversa y con las dificultades de comercio y navegación derivadas del inicio de la guerra de los Siete Años. La manera de afrontar la plaga, utilizando «medios técnicos» combinados con otros de carácter «religioso» o «mágico» muy ...

  2. Potencialidad Celular Evolutiva y Medicina Regenerativa

    Rojas, Mariana; Meruane, Manuel

    2012-01-01

    Las células derivadas del embrioblasto o macizo celular interno (MCI) del blastocisto corresponden a las células madres embrionarias, ellas son pluripotentes, debido a que tienen la capacidad de generar todas las estirpes celulares y al resto, se les conoce como células madres adultas porque tienen un potencial de diferenciación mucho más restringido. Dentro de las células adultas podemos reconocer las células madre hematopoyéticas de la médula ósea y las células madres mesenquimales presente...

  3. A solução técnica para os problemas ambientais

    Guillermo Foladori

    2012-06-01

    Full Text Available http://dx.doi.org/10.1590/S1414-49802012000100008 Neste ensaio, argumenta-se que a discussão ambiental tem sido reduzida a uma questão técnica. E que esta dita redução implica em considerar a tecnologia como neutra e não em considerar as tendências derivadas das relações sociais. Conclui-se com os limites que as relações capitalistas supõem para solucionar os grandes problemas ambientais.

  4. Aspectos básicos de la fijación de nitrógeno atmosférico por parte de bacterias. Estudio en el laboratorio de educación secundaria

    José Pedro López Pérez

    2016-01-01

    Full Text Available La fijación de nitrógeno atmosférico por parte de microorganismos tiene notable importancia ambiental e industrial relacionada con el incremento de la fertilidad y productividad en los suelos, soporte de las plantas y las redes tróficas derivadas. En el presente artículo se especifica un sencillo protocolo de laboratorio, junto con la base teórica que lo sustenta, con el objetivo de observar los microorganismos responsables de la fijación en los nódulos de leguminosas.

  5. Proceso de alta de una unidad de cuidados intensivos. Medición de la ansiedad y factores relacionados

    Ricart Basagaña, Mª Teresa

    2015-01-01

    La ansiedad es un diagnóstico que frecuentemente se relaciona con los enfermos de las unidades de cuidados intensivos (UCI). Aunque la literatura aporta evidencias suficientes para tener en cuenta el problema de la ansiedad y las complicaciones derivadas, aún desconocemos hasta qué punto la ansiedad tiene impacto en nuestro contexto cultural y cuáles son los factores que condicionan que algunas personas presenten niveles de ansiedad más altos que otras cuando son dados de alta de nuestras UC...

  6. Desarrollo de un sistema de suspensión magnética para la determinación de densidad de líquidos

    Centeno González, Luz María; Castillo Castañeda, Eduardo; Becerra Santiago, Luis Omar; Rochín García, Alberto

    2013-01-01

    La densidad es una magnitud derivada de las magnitudes de base masa y longitud, está definida como masa por unidad de volumen y su unidad en el Sistema Internacional de Unidades (SI) es el kg/m3. En las últimas cinco décadas, en el ámbito de la metrología primaria, se han desarrollado sistemas de suspensión magnética para la determinación de densidad de fluidos, lo que ha permitido realizar investigaciones sobre las características físicas de líquidos y gases. El presente trabajo tiene como o...

  7. Procesos de plasticidad cerebral en pacientes con daño adquirido

    Márquez Noriego, Blanca Esther

    2016-01-01

    Los accidentes cerebrovasculares y los traumatismos craneoencefálicos son las dos patologías principales causantes de daño cerebral adquirido. Los avances médicos han permitido disminuir considerablemente la mortalidad derivada de dichas patologías. Consecuentemente, el número de personas que padecen déficits derivados de estas lesiones aumenta a nivel mundial. Estos déficits son consecuencia del daño cerebral, el cual puede afectar a varias áreas, según las características propias de la lesi...

  8. Osteotomia segmentaria

    Cava-Vergiú, Carlos-Enrique; Flores Cueto, Walter; Cárdenas Sornoza, Aníbal

    2006-01-01

    Desarrolla un caso clínico en el que se realiza una osteotomía segmentaria en el centro quirúrgico de la Clínica Especializada en Odontología de la Universidad de San Martín de Porres. La paciente ingresa a la clínica requiriendo tratamiento protésico, pero debido al insuficiente espacio por la extrusión de piezas sin antagonista, es derivada al centro quirúrgico de la clínica para evaluarla. La paciente es programada para una osteotomía segmentaria bilateral posterior. Se toman modelos de es...

  9. Masonería y Sociabilidad en el centro y sur de la campaña bonaerense: Fines del siglo XIX principios del XX

    Yolanda de Paz Trueba

    2011-12-01

    Full Text Available El objetivo de este trabajo es reflexionar en torno a la relación establecida entre la sociabilidad política derivada de la influencia masónica y otras formas de sociabilidad previas ligadas al catolicismo, en el marco de la construcción del Estado en sus diversos niveles a fines del siglo XIX. Este abordaje será realizado a través del análisis de pueblos de la campaña bonaerense, espacios no estudiados en este sentido hasta el momento.

  10. Varia??es morfol?gicas e geogr?ficas no sincr?nio do peixe-boi da Amaz?nia Trichechus inunguis (Natterer, 1883)

    Valdevino, Gisele de Castro Maciel

    2016-01-01

    peixe-boi-da-Amaz?nia (Trichechus inunguis) ? end?mico da bacia Amaz?nica e exclusivo de ?gua doce. Apresenta apomorfias em rela??o aos outros triquequ?deos, derivadas de sua adapta??o ao ambiente dulc?cola e distribui-se desde as cabeceiras de rios no Equador, Peru e Col?mbia at? o estu?rio do Rio Amazonas, no Brasil. Apesar dos estudos sobre a morfologia desta esp?cie, nenhum estudo ontogen?tico sincraniano foi desenvolvido ao longo de sua distribui??o. Estudos morfol?gicos e...

  11. La discapacidad en la empresa: ¿oportunidad o desafío?

    González Álvarez, Marta

    2010-01-01

    Este artículo presenta la contratación de personas con discapacidad como una fuente de valor reputacional para la empresa. La autora analiza las supuestas ventajas competitivas derivadas de la presencia de estas personas en la plantilla -mejor clima laboral, mayor sentido de pertenencia, aumento del rendimiento económico, y mejor reputación-, ofreciendo datos empíricos obtenidos en julio de 2009, a través de entrevistas en profundidad, a cincuenta responsables de personal del sector industria...

  12. Diseño de nuevas bebidas funcionales enriquecidas en fitoquímicos bioactivos = Design of new functional beverages rich in bioactive phytochemicals

    Gironés Vilaplana, Amadeo

    2014-01-01

    La elaboración de bebidas derivadas de frutas ricas en compuestos bioactivos y biodisponibles, puede ser la base de nuevos alimentos funcionales para la prevención de diferentes problemas de salud dada la estrecha relación que existe entre un estado fisiológico de estrés oxidativo como desencadenante de diferentes problemas de salud (cardiovascular, metabolismo de glucosa y de lípidos, actividad neuronal, ansiedad, etc.). En este sentido el limón es un fruto rico en estos compuestos bioactivo...

  13. La vida en torno al café: marginación social de pequeños productores en San Pedro Cafetitlán, Oaxaca, México

    Israel Morales Becerra

    2013-01-01

    Se presenta una descripción etnográfica del trabajo de campo realizado en San Pedro Cafetitlán, Oaxaca, México sobre la situación de marginación social derivada de la implementación del modelo económico neoliberal; se hace una interpretación del significado que tiene el cultivo del café en la vida de los pobladores. Destaca el hecho de que las generaciones mayores de 60 años aun valoran el recurso, tienen identidad con la tierra y esperanzas en su café; sin embargo, para las nuevas generacion...

  14. MAV te observa, entraremos en acción: Las mujeres en el sistema del arte español. Sobre piedras y vientos de igualdad

    Marián López Fdz. Cao

    2014-01-01

    Full Text Available Este artículo tiene como objetivo poner de manifiesto las carencias que todavía muestra el sistema del arte español para alcanzar la igualdad en materia de género. Asimismo pretende mostrar cómo desde el movimiento asociacionista la sociedad española está respondiendo y exigiendo a las administraciones públicas e instituciones culturales el cumplimiento de la constitución y las leyes derivadas para garantizar la igualdad.

  15. Diversidad microbiana en ambientes volcánicos

    Urbieta, María Sofía

    2013-01-01

    El sistema Copahue-Caviahue, que comprende el Volcán Copahue, el Río Agrio, varias manifestaciones geotermales de distintas temperaturas además de lagunas, lagos y otros cursos de agua, es un ambiente natural de características principalmente termales y ácidas, derivadas de su origen volcánico. Estos hábitats están colonizados por microorganismos especialmente adaptados para sobrevivir en condiciones extremas, por lo que son denominados extremófilos. Los extremófilos participan activamente en...

  16. La Ecuación de Hill con Potencial Irregular

    Santiago Cambronero

    2012-03-01

    Full Text Available Se considera la ecuación de Hill cuyo potencial es la derivada formal de una función Hölder - continua de parámetro \\theta \\in (0,1 y se muestra que las soluciones de la versión discreta correspondiente convergen adecuadamente a las soluciones de la ecuación original. Este hecho se usa para establecer teoremas de existencia de soluciones para este caso singular y para deducir algunas propiedades de las soluciones y el discriminante de la ecuación estudiada.

  17. Efectos de la comida sobre variables antropométricas y de grasa de tronco y visceral por bioimpedancia

    Diego-Acosta, Ángel Mario; Fernández-Vázquez, R; García-Vega, MM; García-Lavigne, JA; Martínez-Blanco, J; Rodríguez-Linares, MV; Ramos-Gil, R; Alvero-Cruz, Jose Ramon

    2014-01-01

    Los efectos de la comida y la bebida sobre las mediciones masa grasa (MG) derivadas por bioimpedancia eléctrica (BIA) tienen efectos que pueden modificar las estimaciones de MG Y masa libre de grasa. El objetivo del trabajo fue determinar si existen diferencias en el perímetro abdominal máximo (PAbM), diámetro sagital abdominal (DSA) como indicadores de obesidad central y en las variables de grasa de tronco y visceral estimadas por BIA. Universidad de Málaga. Campus de Excelencia Internaci...

  18. La protección de los derechos a la salud y la seguridad social en Argentina

    Bazán, Víctor

    2017-01-01

    En este trabajo se examinará la paulatina plasmación de los derechos a la salud y la seguridad social en las cláusulas constitucionales de Argentina, con particular énfasis en la última reforma constitucional operada en 1994, que exhibe una fuerte textura social, tanto en sus propias normas como en las contenidas en los instrumentos internacionales sobre derechos humanos, a los que se ha adjudicado jerarquía constitucional (originaria o derivada), dando cuerpo al ¿bloque de constitucionalidad...

  19. Riesgo y derechos sociales: la visión del Banco Mundial y su impacto en Argentina

    Etchichury, Horacio Javier

    2016-01-01

    El trabajo revisa la visión del Banco Mundial en materia de políticas sociales según el planteo efectuado en la edición 2014 del World Development Report, centrada en las nociones de riesgo y  administración del riesgo. Se coteja esta visión con el marco de derechos sociales que la Argentina ha reconocido y consagrado en su Constitución. El texto analiza las tensiones entre las pautas derivadas de las propuestas del Banco Mundial y las obligaciones del Estado argentino. ----------------------...

  20. Sobre aplicaciones conformes hiperbólicamente convexas

    Mejía, Diego; Pommerenke, Christian

    2012-01-01

    Se dice que una transformaci6n conforme f del disco unidad D del plano complejo en sí mismo es hiperbólicamente convexa si el segmento de recta hiperbólica que une cualquier par de puntos de f (D) está a su vez contenido en f (D). En este trabajo estudiaremos algunas cantidades relacionadas con estas funciones que no permanecen invariantes bajo los automorfismos  conformes de D, a saber, la derivada, el modulo de continuidad y los coeficientes de la expansión en serie de Taylor alrededor del ...

  1. Estudio experimental y teórico de mezclas líquidas binarias formadas por 1-alcoholes y ciclohexilamina

    Sanz del Soto, Luis Felipe

    2016-01-01

    Mediante la medida experimental de la densidad, viscosidad, índice de refracción y permitividad a tres temperaturas (293.15, 298.15 y 303.15 K) y el cálculo de diferentes magnitudes derivadas, se ha procedido a estudiar las interacciones intermoleculares que se producen en las mezclas líquidas binarias de 1-alcohol (metanol, 1-propanol, 1-butanol, 1-heptanol y 1-decanol) con la ciclohexilamina. Departamento de Física Aplicada Doctorado en Física

  2. Adaptación cultural de instrumentos utilizados en salud ocupacional

    Alexandre Neusa Maria Costa

    2002-01-01

    Full Text Available Se han creado numerosos instrumentos estandarizados para evaluar el estado de salud y la eficacia de los tratamientos. Sin embargo, la mayoría de ellos han sido desarrollados y validados en la lengua inglesa. En la literatura se recomienda la utilización de escalas y cuestionarios estandarizados cuyos resultados puedan ser comparados internacionalmente. Las diferencias culturales no permiten hacer una simple traducción de estos instrumentos. En este artículo se resumen normas sistematizadas para la adaptación cultural de instrumentos utilizados en salud ocupacional, derivadas de investigaciones especializadas.

  3. Determinantes de la gestión clínica en atención médica domiciliaria de personas con secuelas de enfermedad cerebro-vascular

    Sánchez Cárdenas, Miguel Antonio

    2012-01-01

    La atención domiciliaria constituye hoy una modalidad de atención que permite solventar las dificultades derivadas de la sobreocupación hospitalaria y la cronicidad, los cuales constituyen un problema de interés en salud pública en los países desarrollados y que pueden ser manejados en el domicilio del paciente como una opción costo-efectiva y segura. Para lo cual es necesario buscar estrategias que permitan su desarrollo, gestión de riesgos y modelos de atención, logrando mejorar las condici...

  4. Un nuevo enfoque para modelos de inversión-consumo

    Juan Pablo Rincón Zapatero

    2000-01-01

    Full Text Available El enfoque clásico para el estudio de pro lemas de control estocástico se asa en la ecuación de Hamilton-Jacobi-Bellman, que caracteriza a la función valor óptimo En este trabajo mostramos que en ciertos problemas es posible deducir ecuaciones en derivadas parciales que caracterizan directamente al control óptimo y que presentan una estructura más sencilla. Aplicamos este nuevo enfoque al estudio de algunos pro lemas de inversión-consumo

  5. Campo de dirección. Método de las isoclinas, en la solución de ecuaciones diferenciales de primer orden

    Castañeda, Pedro; Quintero, Arely; Moreno, Aura Matilde

    2007-01-01

    En la descripción del proceso de modelado se habla acerca de formular un modelo matemático de un problema del mundo real a través de un razonamiento intuitivo acerca del mismo o a partir de leyes físicas basadas en la evidencia proveniente de la experimentación. El modelo matemático a menudo toma la forma de una ecuación diferencial, es decir, una ecuación que contiene una función desconocida y algunas de sus derivadas.

  6. Método para incrementar la fertilidad de las plantas

    Abbas, Mohamad; Alabadí, David; Blázquez, Miguel Ángel

    2015-01-01

    [ES] Método para incrementar la fertilidad de las plantas. La presente invención se relaciona con un método para incrementar la fertilidad de una planta que comprende inhibir, disminuir o bloquear la expresión del gen que codifica la proteína IAMT1 con respecto a un control o la actividad de la proteína IAMT1, y la planta derivada de la aplicación de dicho método, así como el uso de gen que codifica la proteína IAMT1 para incrementar de fertilidad de la planta.

  7. Utilidad y fiabilidad de las escalas contemporáneas de estimación de riesgo en enfermedades cardiovasculares

    Abu Assi, Emad

    2013-01-01

    Las enfermedades cardiovasculares son la principal causa de morbimortalidad en los países desarrollados. Además, su coste es muy elevado, que, junto con el envejecimiento progresivo de nuestra población, exige estrategias de prevención a fin de contrarrestar sus efectos. En los últimos años, se desarrollaron varias escalas de estratificación de riesgo en el ámbito de las enfermedades cardiovasculares, como el síndrome coronario agudo y las hemorragias derivadas de su manejo; eventos tromboemb...

  8. Fijación de estrategias de precios en el comercio electronico. Un modelo de decisión

    Bernal García, Juan Jesús; Briones Perona, Carlos; Martínez María Dolores, Soledad María

    2002-01-01

    En la actualidad nos encontramos con el nacimiento de nuevas tipologías de mercado derivadas de los múltiples avances tecnológicos surgidos en las últimas décadas. El entorno de Internet y las acciones comerciales que en él se efectúan, conllevan una serie de peculiaridades que lo identifican, aunque básicamente funcionan como los mercados considerados tradicionales. Nos seguimos enfrentando por tanto, a un problema básico en cualquier mercado: el desconocimiento a priori por p...

  9. Simulación numérica : ecuación de difusión

    Millán, Zulma; Torre, Leonor de la; Oliva, Laura; Berenguer, María del Carmen

    2011-01-01

    La simulación numérica es una herramienta eficaz en las ciencias aplicadas, para la determinación de soluciones y la predicción del comportamiento de las mismas, sin recurrir a la experimentación. Permite la recreación matemática de procesos físicos que aparecen con frecuencia en el área de Ingeniería. El uso de simulaciones numéricas para estudiar ecuaciones diferenciales en derivadas parciales, en particular la ecuación de difusión, requiere normalmente de un cuidadoso estudio d...

  10. Una aplicación de las funciones débilmente contractivas a problemas de valor en la frontera de funciones con valores en intervalos

    Vladimir Angulo-Castillo

    2014-06-01

    Full Text Available Se estudia la existencia y unicidad de soluciones para problemas de valor en la frontera asociadas a ecuaciones diferenciales de funciones con valores en intervalos, usando la derivada de Hukuhara y algunos teoremas de punto fijo de funciones débilmente contractivas definidas en conjuntos parcialmente ordenados. Abstract. We study the existence and uniqueness of solutions for boundary value problems associated to differential equations of interval-valued functions, by using the derivative of Hukuhara and some fixed point theorems for weakly contractive mappings defined on partially ordered sets.

  11. Economía Política I, 2010-11

    Antón Pérez, José Ignacio

    2010-01-01

    I. Materiales de clase: Teoría: 0. Conceptos básicos; 1. El problema económico; 2. Las ganancias derivadas del comercio; 3. Elementos básicos de la oferta y la demanda; 4. Elasticidades; 5. La medición del bienestar y la política económica; 6. La empresa: producción, costes y beneficios; 7. Las empresas en los mercados competitivos; Ejercicios: Ejercicios del Tema 2; Ejercicios del Tema 3; Ejercicios del Tema 4; Ejercicios del Tema 5; Ejercicios del Tema 6 y 7; Ejercicios de Repaso. II. Bibli...

  12. El dolor, quinto signo vital

    Universidad del Rosario, Programa de Divulgación Científica

    2006-01-01

    Las heridas producidas por trauma a causa del proyectil de un arma de fuego en los enfrentamientos bélicos que se ven a diario en la prensa, las lesiones por elementos contundentes en riñas, las amputaciones derivadas de las lesiones de guerra y el dolor del alma de aquellas personas que pierden a sus seres queridos, son algunos de los focos de dolor a los que se enfrentan cientos de colombianos. El sufrimiento por dolor es un problema de salud pública. En los Estados Unidos más de 300 mi...

  13. Interacciones entre semillas y escarabajos del estiércol (scarabaeinae) en un bosque tropical seco

    Julissa Ocampo-Castillo; Ellen Andresen

    2018-01-01

    Los escarabajos del estiércol (Scarabaeinae) son insectos importantes en muchos ecosistemas terrestres por susfunciones ecológicas, derivadas del comportamiento de remover las heces de vertebrados. Este grupo de insectoses particularmente abundante en los bosques tropicales (BT). Sus funciones ecológicas han sido principalmenteestudiadas en los BT húmedos, existiendo poca información para los BT secos. Se realizaron experimentos de campoen la Estación de Biología de Chamela (Jalisco, México) ...

  14. Contraposición del concepto de tipo anaclítico de elección de objeto en Freud y Lacan Contrast of the anaclitic object-choice concept in Freud and Lacan

    Roberto Mazzuca; Santiago Mazzuca; Florencia Surmani

    2009-01-01

    Este trabajo articula el concepto freudiano de elección de objeto de tipo anaclítico con el concepto lacaniano de relación anaclítica, examinando sus relaciones, semejanzas y diferencias. En primer lugar, se delimita el concepto freudiano, se subraya la complejidad de sus relaciones con otros conceptos de la teoría de Freud, y se destaca las dificultades de comprensión en los desarrollos posfreudianos, derivadas de esa complejidad. En segundo lugar, se delimita el concepto lacaniano, o más bi...

  15. Impacto tecnológico y acción educativa: configuración social, antropológica y educativa

    Agustín REQUEJO OSORIO

    2009-11-01

    Full Text Available El presente trabajo trata de presentar un breve estudio referido al impacto de las nuevas tecnologías sobre la acción educativa. Reconociendo la información como una tendencia básica de la sociedad actual se estudian sus repercusiones tanto a nivel social como antropológico. Finalmente se analizan y se proponen las pautas de acción derivadas de la influencia de las nuevas tecnologías sobre el sistema educativo.

  16. Octadecanoides como reguladores de la defensa de las plantas

    G. Camarena Gutiérrez

    2002-01-01

    En años recientes muchas moléculas lipoides muy potentes han sido identificadas, comprenden compuestos lipofílicos no derivados de lípidos como los brasinoesteroides triterpenoides, otros que parcialmente son de origen lipídico como los lipo-oligosacáridos, factores de nodulación de especies de Rhizobium que pueden tener parientes endógenos en las plantas, y un tercer grupo, los octadecanoides, cuyas estructuras son derivadas de ácidos grasos vegetales. Las señales mediadas por lípid...

  17. Um refinamento da estrutura da camada de aplicação do RM-OSI/ISO e aspectos de sua implementação em um sistema didatico de comunicação

    Flavio Morais de Assis Silva

    1993-01-01

    Resumo: Esta dissertação consiste de Uma definição mais precisa de funcionalidades para os componentes da camada de Aplicação do RM-OSI/ISO (Reference Model - Open Systems Interconection / International Organization for Standardization). Esta definição de funcionalidades tem a finalidade de esclarecer os relacionamentos que há entre os componentes desta camada e de servir de uma base conceitual, a partir da qual estruturas para implementações possam ser derivadas. As funcionalidades apresenta...

  18. Las células troncales pluripotenciales en la terapia celular

    J.A. Gámez Escalona; N. López Moratalla

    2014-01-01

    Las células con pluripotencialidad inducida (iPS) son un nuevo tipo de célula troncal derivada de células somáticas humanas, mediante reprogramación con factores de transcripción. Estas células iPS tienen características de las células troncales embrionarias, como la capacidad de convertirse en todos los tipos de células diferenciadas del organismo. A corto plazo, las células de pacientes reprogramadas están siendo útiles para crear modelos celulares de enfermedades, en las que estudiar los p...

  19. Impacto en el desarrollo poblacional: contaminación de las fuentes de agua y sus efectos sobre el sistema nervioso y la conducta

    Iorio, ALBERTO ANDRES; Muzio, Ruben Nestor

    2016-01-01

    Las soluciones eficaces para enfrentar el problema de la contaminación de las aguas deben contemplar el desarrollo de obras de infraestructura de plantas potabilizadoras de desalinización que lleguen a obtener agua con cifras aceptadas como potables. Otra consideración significativa a tener en cuenta, derivada de la existencia de arsénico en aguas y suelos, es la posible contaminación de alimentos de origen vegetal y animal que crecen y se crían en el área. En los últimos años se han desarrol...

  20. Aplicación del método Six-Sigma para reducir la variabilidad en un proceso de fabricación

    Muñoz Castro, Marta

    2016-01-01

    El objetivo del proyecto es resolver la problemática derivada de la alta variabilidad de producción de un proceso industrial del sector de la producción de cables. Para llevar a cabo el proyecto se sigue la filosofía de mejora continua por excelencia: Six-Sigma. A modo introductorio se presenta la empresa, el proceso de producción completo del cable en el que se enmarca el subproceso que se estudia en el proyecto: el envasado. Este subproceso se detalla en más profundidad para una mejor co...