WorldWideScience

Sample records for canal para simular

  1. MODELO PARA SIMULAR LA HOMEÓSTASIS NEURONAL DURANTE UN INFLUJO INCREMENTADO DEL CALCIO A TRAVÉS DEL CANAL ASOCIADO AL RECEPTOR IONOTRÓPICO DE GLUTAMATO ACTIVADO POR N-METIL-D-ASPARTATO

    Directory of Open Access Journals (Sweden)

    L. Lareo

    2005-12-01

    Full Text Available Dada la importancia del receptor ionotrópico de glutamato activado por N-Metil-D-Aspartato en los procesos de aprendizaje y la formación de la memoria mediados por el transporte de calcio a través del canal asociado a dicho receptor resulta importante desarrollar modelos que permitan comprender la homeóstasis que le permite a la neurona manejar incrementos en el flujo de dicho catión sin llegar a desarrollar procesos necróticos ni apoptóticos. Este trabajo presenta una sencilla simulación de parte de los procesos metabólicos asociados al receptor como un paso inicial para comprender los mecanismos subyacentes al aprendizaje y memoria.

  2. MICROMUNDO PARA SIMULAR UN MERCADO ELÉCTRICO DE CORTO PLAZO

    Directory of Open Access Journals (Sweden)

    Carlos Jaime Franco

    2012-12-01

    Full Text Available En este trabajo se presenta un micromundo para la simulación de una bolsa de energía, el cual se elaboró en respuesta a la necesidad de facilitar el aprendizaje del esquema de bolsa de energía con despacho centralizado a los interesados en este mercado. El micromundo cuenta con un modelo climático para simular los fenómenos de El Niño y La Niña, y con un modelo para la generación de los precios de oferta de los generadores, además es altamente parametrizable y permite simular diversos tipos de mercados eléctricos.

  3. MODELO PARA SIMULAR LA HOMEÓSTASIS NEURONAL DURANTE UN INFLUJO INCREMENTADO DEL CALCIO A TRAVÉS DEL CANAL ASOCIADO AL RECEPTOR IONOTRÓPICO DE GLUTAMATO ACTIVADO POR N-METIL-D-ASPARTATO

    OpenAIRE

    Lareo, L.; Departamento de Nutrición Y Bioquímica Facultad de Ciencias Pontificia Universidad Javeriana, Bogotá; Albarracín, S.; Departamento de Nutrición Y Bioquímica Facultad de Ciencias Pontificia Universidad Javeriana, Bogotá

    2005-01-01

    Dada la importancia del receptor ionotrópico de glutamato activado por N-Metil-D-Aspartato en los procesos de aprendizaje y la formación de la memoria mediados por el transporte de calcio a través del canal asociado a dicho receptor resulta importante desarrollar modelos que permitan comprender la homeóstasis que le permite a la neurona manejar incrementos en el flujo de dicho catión sin llegar a desarrollar procesos necróticos ni apoptóticos. Este trabajo presenta una sencilla simulación de ...

  4. EMPLEO DEL PROGRAMA VOLCFLOW PARA SIMULAR FLUJOS PIROCLÁSTICOS DEL VOLCÁN CERRO MACHÍN, TOLIMA, COLOMBIA

    Directory of Open Access Journals (Sweden)

    Elsa Adriana Cárdenas Quiroga

    2013-01-01

    Full Text Available Se presentan los resultados de simular futuros flujos piroclásticos que podría producir el Volcán Cerro Machín, ubicado en la Cordillera Central de Colombia. Esta simulación se realizó con el programa VolcFlow desarrollado por el Laboratorio de Magmas y Volcanes de la Universidad Blaise Pascal, Francia, diseñado especialmente para modelar el comportamiento de este tipo de productos volcánicos, ya que está basado en las características reológicas de esos flujos. Se comparan las áreas que serían potencialmente afectadas por una erupción de ese tipo y los espesores del material que se depositaría con resultados obtenidos de simulaciones realizadas con un Model Builder desarrollado en ARC GIS por el Grupo de Investigación Geomática Aplicada de la Universidad Militar Nueva Granada en Colombia, obteniéndose resultados similares.

  5. Laboratorio Virtual y Remoto para Simular, Monitorizar y Controlar un Sistema de Riego por Goteo en Olivos

    Directory of Open Access Journals (Sweden)

    Flavio Capraro

    2010-01-01

    Full Text Available Resumen: Se presenta el diseño y puesta en marcha de un laboratorio para ensayar en simulación estrategias de control y riego, que luego de forma remota se ejecutan a campo en un sistema de riego por goteo (planta piloto. La aplicación involucra el desarrollo de un software para efectuar la simulación, la monitorización y el control remoto de la planta piloto. Se describen la instalación de una red de sensores de humedad de suelo, la red de comunicaciones y el hardware requerido para el control remoto. El laboratorio y la planta piloto están ubicados en una plantación de olivos, situado en la provincia de San Juan, Argentina. Palabras clave: Laboratorio de educación, simulación computacional, control remoto, control en línea, sistema de control supervisado, agricultura

  6. Revestimientos especiales para diques y canales

    Directory of Open Access Journals (Sweden)

    Zorzi, Silvano

    1964-11-01

    Full Text Available This paper summarizes the possibilities and advantages of adopting special facings for dykes and canals, and generally for all large hydraulic works, where waterproofing is of paramount importance. Technical advances in recent years have made it possible to prefabricate many facing units used in these types of works; large slabs, made in reinforced and prestressed concrete, are flexible, and watertight. Although there are many possibilities and types of facing treatments, the one described here is outstanding. It consists of narrow slabs, highly flexible, placed transversally with respect to the canal axis. They are attached with cement mortar, and the joints are finally sealed with a special mortar, called «Emboco». In this article a description is also given of a series of projects, where facing treatments have been used, which are now successfully in service. Finally some general and simple advise is given on the best procedure to apply these facing treatments in the most effective and economic manner.En este trabajo se resumen las posibilidades y ventajas que ofrecen los revestimientos especiales de diques y taludes de canales y, en general, en todas las grandes obras hidráulicas, en que la impermeabilización es de mayor importancia al tratar de conservar los caudales iniciales o la retención de aguas embalsadas, según los casos. Los progresos de las técnicas modernas, en particular la prefabricación, han permitido este tipo de revestimientos con losas de gran longitud, extremadamente flexibles e impermeables, de hormigón armado y pretensado. Aunque son muchas las posibilidades y tipos de revestimiento, destaca el que a continuación se expone: consiste en placas o losas estrechas, de gran flexibilidad, colocadas transversalmente al eje del canal sobre tongadas de mortero de cemento, y cuyas juntas se sellan, finalmente, con un mortero especial llamado «Emboco». Complementan la exposición teórica del método una serie de

  7. Diseño y caracterización de un móvil robótico multiconfigurable para simular las cargas verticales sobre una maqueta de pasarela peatonal

    OpenAIRE

    Muñoz Alonso, Diego

    2017-01-01

    Diseño y caracterización de un móvil robótico multiconfigurable para simular las cargas verticales sobre una maqueta de pasarela peatonal. diseño de una autómata humanoide y de una móvil robótico rodante. Calibración estática y dinámica de sensores de medida y caracterización posterior de un sistema mecánico de un grado de libertad. Caracterización de las acciones verticales del robot sobre una plataforma, y ensayos normales y críticos en la viga de simulación con sensores de fuerza y presión...

  8. Derivación analítica del tiempo de llegada en modelos de canal basados en geometría para sistemas inalámbricos

    Directory of Open Access Journals (Sweden)

    M.R. Arias

    2007-11-01

    Full Text Available Este artículo presenta una propuesta analítica para derivar la función de densidad de probabilidad de potencia (PDF, por sus siglas en ingles del tiempo de llegada (TOA, por sus siglas en inglés y su aplicación en los modelos de canal estadísticos basados en geometría para ambientes urbanos. En éste artículo proponemos un modelo de canal utilizando el método por agrupamiento, y lo empleamos para derivar la PDF del tiempo de llegada de la señal de multitrayectorias. Para evaluar la PDF teórica propuesta por agrupamiento en el dominio del tiempo, hacemos simulaciones por computadora del modelo de canal basado en geometría propuesto y lo comparamos con los resultados experimentales publicados en la literatura. La comparación con los resultados experimentales revelan una buena aproximación. La PDF por agrupamiento derivada se puede utilizar para simular la dispersión temporal de la señal de multitrayectorias agrupadas para una variedad de condiciones de propagación en ambientes urbanos para cuantificar parámetros estadísticos de segundo orden, es decir, la difusión de retardo para una forma elíptica específica dada por el grupo de señales de multitrayectorias.

  9. Inverse-FEM Characterization of a Brain Tissue Phantom to Simulate Compression and Indentation Caracterización de tejido cerebral artificial utilizando Inverse-FEM para simular indentación y comprensión

    Directory of Open Access Journals (Sweden)

    Elizabeth Mesa-Múnera

    2012-12-01

    Full Text Available The realistic simulation of tool-tissue interactions is necessary for the development of surgical simulators and one of the key element for it realism is accurate bio-mechanical tissue models. In this paper, we determined the mechanical properties of soft tissue by minimizing the difference between experimental measurements and the analytical or simulated solution of the deformation. Then, we selected the best model parameters that fit the experimental data to simulate a bonded compression and a needle indentation with a flat-tip. We show that the inverse FEM allows accurate material property estimation. We also validated our results using multiple tool-tissue interactions over the same specimen.Una simulación realista de la interacción tejido-herramienta es necesaria para desarrollar simuldores quirúrgicos, y la presición en modelos biomecánicos de tejidos es determinante para cumplir tal fin. Los trabajos previos han caracterizado las propiedades de tejidos blandos; sin embargo, ha faltado una validación apropiada de los resultados. En este trabajo se determinaron las propiedades mecánicas de un tejido blando minimizando la diferencia entre las mediciones experimentales y la solución analítica o simulada del problema. Luego, fueron seleccionados los parámetros que mejor se ajustaron a los datos experimentales para simular una compresión con fricción y la indentación de una aguja con punta plana. Se concluye que el inverse-FEM permite la precisa estimación de las propiedades del material. Además, estos resultados fueron validados con varias interacciones tejido-herramienta sobre el mismo espécimen.

  10. Sistema de monitorización de temperatura para una cámara de co-cultivo celular para simular un procedimiento de transplante hepático

    OpenAIRE

    Villalba Burrull, Júlia

    2015-01-01

    El trasplantament hepàtic és un procediment del que s’han realitzat nombrosos estudis al llarg dels anys. En aquest projecte, s’ha dissenyat i implementat un sistema per simular les condicions d’un procediment de transplantament hepàtic en una càmera de co-cultiu cel·lular, que simula les condicions fisiològiques del fetge (Liver on a Chip), per poder fer estudis sense utilitzar models animals. Un dels factors més importants per l’èxit del transplantament, que sempre ha esta...

  11. GeoSteamNet: A computer code to simulate geothermal steam flow in a pipeline network; GeoSteamNet: Programa de computo para simular el flujo de vapor geotermico de una red de vaporductos

    Energy Technology Data Exchange (ETDEWEB)

    Verma P., Mahendra; Aragon A., Alfonso [Instituto de Investigaciones Electricas, Cuernavaca, Morelos (Mexico)]. E-mail: mahendra@iie.org.mx; Ruiz L., Alejando; Mendoza C., Alfredo [Comision Federal de Electricidad, Campo Geotermico Los Azufres, Campamento Agua Fria, Michoacan (Mexico)

    2011-07-15

    A computer package, GeoSteamNet, was developed to simulate steam transport in a pipeline network of a geothermal field. The fluid motion is governed by the following basic principles: conservation of mass, linear momentum principle (Newton's second law or the Navier Stokes equations), and the first and second laws of thermodynamics. The second law of thermodynamics defines the direction of a spontaneous process, which is indirectly validated in the algorithm as vapor flows from high-to-low pressure, and heat flows from high-to-low temperatures. The nonlinear equations are solved with the Newton-Raphson method. Using the ActiveX component OrificeMeter, the steam-flow balance was calculated for power plants U-15 and U-16 in Los Azufres Geothermal Field, Mich., in February 2009. U-15 was fed by the production wells AZ-04, AZ-28, AZ-30, AZ-65D, and AZ-66, whereas wells AZ-28A, AZ-45, AZ-56, AZ-67, AZ-69D were connected to U-16. The analytical error is within {+-}4%, which is acceptable for practical purposes for steam-supply management, considering the uncertainties in parameters, such as pressure, temperature, pressure fluctuation at the wellhead, etc. The steam simulation results by GeoSteamNet for a hypothetical-pipeline network in a geothermal system with two production wells and a power plant illustrate its functionality. Several points need to be emphasized. For a specific geometry-pipeline network, there is only a certain amount of mass (vapor) that can be transported at a given pressure at the wellheads and the power plant. The construction and modification of a pipeline network is very expensive and the production of geothermal wells depends on many natural factors; therefore, there is need to conduct a tolerance study for each component of the network. A simulation study of the virtual-pipeline network for the design of a geothermal power plant can save money, effort, and time. [Spanish] Se desarrollo un paquete de computo, GeoSteamNet, para simular el

  12. Evaluation of a model to Simulate Net Radiation Over a Vineyar cv. Cabernet Sauvignon Evaluación de un Modelo para Simular el Flujo de Radiación Neta Sobre un Viñedo cv. Cabernet Sauvignon

    Directory of Open Access Journals (Sweden)

    Marcos Carrasco

    2008-06-01

    Full Text Available Net radiation (Rn is the main energy balance component controlling evaporation and transpiration processes. In this regard, this study evaluated two models to estimate Rno above a commercial vineyard (Vitis vinifera cv. Cabernet Sauvignon located in Pencahue Valley, Maule Region (35º22’ S; 71°47’ Wl; 75 m.a.s.l.. An automatic meteorological station (AMS was installed in the central part of the vineyard and used to measure Rn, solar radiation (Rsi, air temperature (Ta, canopy temperature (Tf and relative humidity (RH. On a 30 min interval, results indicated that model Rne1 (assuming Ta ≠ Tf and model Rne2 (assuming Ta = Tf were able to estimate Rn with a mean absolute error (MAE of less than 40 W m-2 and root mean square error (RMSE of less than 61 W m-2. On daily intervals, the two models estimated Rno with MAE and RMSE values of less than 1.68 and 1.75 MJ m-2 d-1, respectively. In global terms, the models presented errors below 9 and 11% on 30 min and daily intervals, respectively. Furthermore, this study indicated that the incorporation of canopy temperature did not improve the Rno estimation substantially, in spite of having a temperature gradient (dT = Tf - Ta between -3 and to 4ºC. These results suggest that an Rne2 model could be used to estimate Rno using Rsi, Ta and RH measurements.El flujo de radiación neta (Rn es el principal componente del balance de energía que determina los procesos de evaporación y transpiración. En este contexto, este estudio evaluó dos modelos para estimar Rno sobre un viñedo (Vitis vinifera L. cv. Cabernet Sauvignon comercial ubicado en el Valle de Pencahue, Región del Maule (35º22’ S; 71º47’ Oeste; 75 m.s.n.m.. Para esto, se ubicó una estación meteorológica automática (AME en la parte central del viñedo para medir Rn, radiación solar (Rsi, temperatura del aire (Ta, temperatura del dosel (Tf y humedad relativa (HR. En intervalos de tiempo de 30 min, los resultados indicaron que el

  13. Entrevista a Jordi Canal para Historia 2.0

    Directory of Open Access Journals (Sweden)

    Miguel Darío Cuadros Sánchez

    2012-07-01

    Full Text Available Jordi Canal es profesor y director de estudios en la École des Hautes Études en Sciences Sociales (EHESS de Paris, uno de los grandes especialistas en historia contemporánea. Cosmopolita y trilingüe (español, catalán y francés, su bibliografía reciente incluye obras de referencia, como autor o editor, «Los éxodos políticos en España, siglos XV-XX» (2007, «Una historia política del carlismo, 1876-1939» (2006. En el marco del XVII Congreso de la Asociación de Colombianista y la presentación de una conferencia sobre historia política en la Maestría de Historia de la Universidad Industrial de Santander, el profesor Jordi Canal visitó la ciudad de Bucaramanga del 3 al 5 a de agosto del presente año y tuvo la amabilidad de brindar sus opiniones a la revista Historia 2.0.

  14. Evaluation of a computer model to simulate water table response to subirrigation Avaliação de um modelo computacional para simular a resposta do lençol freático à subirrigação

    Directory of Open Access Journals (Sweden)

    Jadir Aparecido Rosa

    2002-12-01

    Full Text Available The objective of this work was to evaluate the water flow computer model, WATABLE, using experimental field observations on water table management plots from a site located near Hastings, FL, USA. The experimental field had scale drainage systems with provisions for subirrigation with buried microirrigation and conventional seepage irrigation systems. Potato (Solanum tuberosum L. growing seasons from years 1996 and 1997 were used to simulate the hydrology of the area. Water table levels, precipitation, irrigation and runoff volumes were continuously monitored. The model simulated the water movement from a buried microirrigation line source and the response of the water table to irrigation, precipitation, evapotranspiration, and deep percolation. The model was calibrated and verified by comparing simulated results with experimental field observations. The model performed very well in simulating seasonal runoff, irrigation volumes, and water table levels during crop growth. The two-dimensional model can be used to investigate different irrigation strategies involving water table management control. Applications of the model include optimization of the water table depth for each growth stage, and duration, frequency, and rate of irrigation.O objetivo deste trabalho foi avaliar o modelo computacional WATABLE usando-se dados de campo obtidos em uma área experimental em manejo de lençol freático, localizada em Hastings, FL, EUA. Na área experimental, estavam instalados um sistema de drenagem e sistemas de irrigação por subsuperfície com irrigação localizada e por canais. Ciclos de cultivo de batata (Solanum tuberosum L., nos anos de 1996 e 1997, foram usados para a simulação da hidrologia da área. Profundidades do lençol freático, chuvas, irrigação e escorrimento superficial foram monitorados constantemente. O modelo simulou o movimento da água a partir de uma linha de irrigação localizada enterrada, e a resposta do nível do len

  15. A new method to simulate the hydrological state of soil under natural conditions Um novo método para simular o estado hidrológico do solo em condições naturais

    Directory of Open Access Journals (Sweden)

    Anna-Katharina Wild

    2009-08-01

    Full Text Available Micro, macro and mesofauna in the soil often respond to fluctuating environmental conditions, resulting in changes of abundance and community structure. Effects of changing soil parameters are normally determined with samples taken in the field and brought to the laboratory, i.e. where natural environmental conditions may not apply. We devised a method (STAFD - soil tubes for artificial flood and drought, which simulates the hydrological state of soil in situ using implanted cores. Control tubes were compared with treatment tubes in which floods of 15, 30, 60 and 90 days, and droughts of 60, 90 and 120 days were simulated in the field. Flooding and drought were found to reduce number of individuals in all soil faunal groups, but the response to drought was slower and not in proportion to the expected decrease of the water content. The results of the simulated floods in particular show the value of the STAFD method for the investigation of such extreme events in natural habitats.As micro, macro e mesofaunas no solo respondem frequentemente à variação das condições ambientais, o que resulta em alterações na abundância e na estrutura da comunidade. Os efeitos das alterações nos parâmetros do solo são normalmente determinados com amostras recolhidas no campo e trazidas ao laboratório, ou seja, onde as condições ambientais naturais podem não ser aplicáveis. Criamos um método (STAFD - tubos de amostra de solo para inundações e secas artificiais, que simula o estado hidrológico do solo in situ com núcleos implantados. As amostras de controle foram comparadas com amostras de tratamentos em que foram simuladas inundações de 15, 30, 60 e 90 dias e secas de 60, 90 e 120 dias no campo. Verificou-se que as inundações e a seca reduziram a quantidade de individuos em todos os grupos de fauna de solo, mas a resposta à seca foi mais lenta e não proporcional à redução prevista no teor de água. Os resultados das inunda

  16. Forced extrusion for removal of impacted third molars close to the mandibular canal Extrusión forzada para extraer los terceros molares impactados cerca del canal mandibular

    Directory of Open Access Journals (Sweden)

    Dennis Flanagan DDS

    2012-03-01

    Full Text Available Impacted mandibular third molars can be located in close proximity to the mandibular canal. This creates a risk for the nerve or artery injury. These are contained in the canal. However, the impacted third molar can be moved coronally by orthodontic means, after removal of overlying bone, and safely extracted. The orthodontic intervention slowly moves the tooth apex away from the mandibular canal and reduces the potential for a neural injury. This method may be useful for older patients with root apices that approximate or are actually located in the mandibular canal. This technique needs further study. There is a theoretical potential for neural or arterial injury from physical contact of the tooth apex as it moves by or through the mandibular canal.Los terceros molares inferiores impactados pueden localizarse muy cerca del canal mandibular. Esto constituye un riesgo de lesión del nervio o la arteria, que se localizan dentro del canal. No obstante, el tercer molar impactado puede desplazarse en dirección coronal con ortodoncia, tras ostectomía del hueso suprayacente, y extraerse sin riesgos. La intervención ortodóncica desplaza lentamente el ápice del diente fuera del canal mandibular y reduce la posibilidad de lesión neural. Este método puede ser útil para pacientes de edad avanzada con ápices dentales que se aproximan o en realidad se localizan en el canal mandibular. La técnica necesita un estudio adicional. Hay la posibilidad teórica de lesión neural o arterial a partir del contacto físico del ápice del diente a medida que se desplaza a través del canal mandibular.

  17. Simultaneous fulfillment of two simularity parameters in fluid dynamic experiments

    Energy Technology Data Exchange (ETDEWEB)

    Schulz-Jander, B.W. [Kassel Univ. (Germany). Inst. fuer Mechanik

    2001-07-01

    In order to obtain reliable results from experiments, it is necessary that fluid dynamic simularity can be achieved. This requires that the ratio of the relevant velocities or forces between experiment and reality assume the same values. In almost all fluid dynamic experiments, the right ratio of inertia and friction forces, given by the Reynolds-Number has to be observed. Including additional similarity parameters, however, may cause problems. In this paper, three cases will be treated: Reynolds- and Mach-Number, Reynolds- and Froude-Number and finally Reynolds - and Strouhal-Number. (orig.)

  18. Canal*Motoboy, São Paulo (Brasil: Comunicación para el cambio social

    Directory of Open Access Journals (Sweden)

    Alisson DIAS GOMES

    2012-02-01

    Full Text Available En la actualidad, los medios de comunicación se contraponen a la propagación de los medios alternativos dirigidos a la democratización de informaciones generadas por ciudadanos comunes. El Canal*Motoboy constituye un ejemplo de esa modalidad de comunicación. Su propuesta es consolidar una estructura abierta para dar voz al colectivo de motoboys de São Paulo (SP en Brasil. Debidamente entrenados y recurriendo al teléfono móvil multimedia, registran su día-a-día en el website Canal*Motoboy. Este artículo analiza este proyecto, a partir de la concepción de la comunicación para el cambio social, una vez que el derecho a la libertad de expresión, históricamente, ha sido expropiado a los ciudadanos por cuenta de la expansión de los conglomerados comunicacionales. Además de la revisión de literatura, el objeto de estudio se ha abordado desde una perspectiva cualitativa a través de la técnica de observación y de entrevista en profundidad para las informaciones de actores del colectivo.

  19. El auto-dren: una nueva protección para los revestimientos de canales

    Directory of Open Access Journals (Sweden)

    Moreno Nieves, Federico

    1986-07-01

    Full Text Available The following considerations are devoted to the study of buried pipes and tanks fracture by uplift. After the description of the fracture process and its circumstances, it is proposed a simple and efficient solution to avoid the problem. We want to thank the Construction and Preservation Engineers of the Hydrographic Confederations for their collaboration and for bestowing their experience that have enabled us to know the problem we describe.Las consideraciones que siguen se dedican al fenómeno de rotura por subpresión en canales y depósitos enterrados. Tras la descripción del proceso de rotura y sus circunstancias, se propone una solución simple y eficaz para obviar el problema. Queremos agradecer a los Ingenieros responsables de Construcción y Conservación de las Confederaciones Hidrográficas su postura de colaboración y transmisión de su experiencia que tanto nos ha posibilitado el conocimiento de la problemática que a continuación tratamos.

  20. Estresse crônico melhora a função miocárdica sem alterar a atividade do canal-L para Ca+2 em ratos

    Directory of Open Access Journals (Sweden)

    Thiago Bruder-Nascimento

    2012-10-01

    Full Text Available FUNDAMENTO: O estresse crônico está associado à remodelação cardíaca; entretanto, os mecanismos permanecem a ser descobertos. OBJETIVO: A proposta deste estudo foi testar a hipótese de que o estresse crônico promove disfunção cardíaca associada a depressão da atividade do canal-L para Ca2+. M MÉTODOS: Ratos Wistar machos com 30 dias de idade (70 - 100 g foram distribuídos dentro de dois grupos: controle (C e estresse crônico (St. O estresse consistiu na imobilização durante 15 semanas, cinco vezes por semana, 1 h por dia. A função cardíaca foi avaliada pela performance do ventrículo esquerdo por meio do ecocardiograma e pelo músculo papilar ventricular isolado. A função do músculo papilar foi avaliada em condição basal e com manobras inotrópicas, como: pós-pausa e elevação na concentração extracelular de Ca2+, na presença ou ausência de um bloqueador específico de canal-L para Ca2+. RESULTADOS: O estresse ficou caracterizado por hipertrofia das glândulas adrenais, aumento nos níveis de corticosterona circulante e por hipertensão arterial. Ainda, o estresse crônico gerou hipertrofia ventricular esquerda. O estresse crônico foi capaz de melhorar a resposta no músculo papilar para manobras inotrópicas positivas. A melhora de função não esteve associada com o canal-L para Ca2+. CONCLUSÃO: O estresse produziu hipertrofia cardíaca; entretanto, nos estudos de músculo papilar isolado, as manobras inotrópicas positivas potencializaram a função cardíaca em ratos estressados, sem o envolvimento do canal-L para Ca2+. Assim os mecanismos responsáveis permanecem incertos para alterações no influxo de Ca2+.

  1. Social tariff for canalized gas: paper proposal; Tarifa social para o gas canalizado: proposta de trabalho

    Energy Technology Data Exchange (ETDEWEB)

    Pelegrini, Marcelo A.; Silva, Wagner M.G. da; Anuatti Neto, Francisco [Universidade de Sao Paulo (ENERQ/EPUSP), SP (Brazil). Escola Politecnica. Centro de Estudos em Regulacao e Qualidade de Energia

    2008-07-01

    This work intends to present some possible philosophies of social policy implementation targeted to low income consumers of canalized gas. The benefits and disadvantages from each philosophy are discussed and a study proposal is presented to define an implementation policy to the State of Sao Paulo. (author)

  2. Um estudo sobre os aspectos que contribuem para a adoção do canal on-line para compra de livros, CDs e DVDs

    Directory of Open Access Journals (Sweden)

    Maria Aparecida Gouvêa

    2013-09-01

    Full Text Available O objetivo neste estudo foi identificar os fatores relevantes na adoção do canal on-line para a realização de compras, tendo como principais referências os modelos Unified Theory of Acceptance and Use of Technology (UTAUT, de Venkatesh et al. (2003, de Heijden, Verhagen e Creemers (2003 e de Bramall, Schoefer e McKechnie (2004. Além da revisão da literatura dos assuntos pertinentes, foi realizada uma pesquisa de campo descritiva, de natureza quantitativa com uma amostra de 172 pessoas residentes na cidade de São Paulo, pertencentes às classes socioeconômicas A, B e C (critério Brasil, compradores de livros, CDs ou DVDs no canal off-line. Os dados coletados foram analisados com o uso de técnicas estatísticas nos contextos uni, bi e multivariado. Aplicou-se a técnica de modelagem de equações estruturais (MEE ou Structural Equation Modeling - SEM para serem identificadas relações de dependência entre construtos e a contribuição de cada um deles na estimação das intenções de adoção da compra pela Internet. Entre os principais resultados encontrados, a atitude em relação ao uso da tecnologia, a confiança e a expectativa de desempenho figuraram como os aspectos mais relevantes para uma possível adoção do canal on-line.

  3. Investigación de mercado para determinar la viabilidad de comercialización en canales no explorados, de los preservativos Jäger en la ciudad de Santiago de Cali

    OpenAIRE

    Delgado Salazar, Adriana Jineth; Orozco Caicedo, Maritza

    2011-01-01

    El presente trabajo, denominado “Investigación de mercado para determinar la viabilidad de comercialización en canales no explorados, de los preservativos Jäger en la ciudad de Santiago de Cali”, tiene como objetivo determinar la viabilidad de comercialización del producto anteriormente mencionado en los canales desatendidos por el actual distribuidor autorizado para el territorio colombiano (Importadora Megga). Entre dichos canales se encuentran los sitios de diversión nocturna, moteles, tie...

  4. Modelagem hidrodinâmica do canal do rio Paraná, trecho Porto São José - Porto 18. Parte II: Calibragem do modelo

    Directory of Open Access Journals (Sweden)

    Astrid Meira Martoni

    1999-05-01

    Full Text Available Neste artigo, apresenta-se a modelagem hidrodinâmica do trecho de canal entre Porto São José e Porto 18. Esta etapa compreendeu os trabalhos de obtenção de dados históricos, levantamentos de campo de níveis e vazões, obtenção dos parâmetros do modelo e análise da distribuição das vazões através dos canais principais. Para as seções internas da discretização foram feitas leituras de níveis nas seções e medidas de descarga usando o medidor ADCP, o que tornou possível estimar os coeficientes de rugosidade. O modelo calibrado constitui um instrumento eficiente para simular dados de níveis e vazões neste trecho do rio.

  5. Diseño y automatización de un sistema de medida para la caracterización del canal radio en interiores

    OpenAIRE

    MARTÍNEZ TOVAL, SANTIAGO

    2017-01-01

    Partiendo de un analizador de redes vectorial y de un sistema de posicionamiento XY, se procederá al diseño y automatización de un sistema de medidas que permita la caracterización del canal radio en interiores a partir de la media del perfil de retardo de potencia. Martínez Toval, S. (2016). Diseño y automatización de un sistema de medida para la caracterización del canal radio en interiores. http://hdl.handle.net/10251/80421. TFGM

  6. Canales de distribución y estrategias de comercialización para la flor colombiana en los Estados Unidos: un marco conceptual

    Directory of Open Access Journals (Sweden)

    LUIS FELIPE SALOM SERNA

    2012-01-01

    Full Text Available El floricultor colombiano no puede desconocer los cambios en tendencias de consumo ni la consolidación del canal retail en su mercado principal, USA. El cuál generará un alto impacto en las características del negocio y el papel de los jugadores en la cadena de suministros. El objetivo de este estudio exploratorio utilizando casos múltiples, es presentar un marco de oportunidades para fortalecer la comercialización de la flor y estructurar canales de distribución acordes a las necesidades del consumidor norteamericano y a los cambios en los hábitos de compra. Las conclusiones, proponen las acciones a emprender por las empresas floricultoras estudiadas a fin de incrementar su competitividad y resolver su dilema actual: contraer oferta para mejorar el precio de venta o incrementar demanda.

  7. Canales de distribución y estrategias de comercialización para la flor colombiana en los Estados Unidos: un marco conceptual

    Directory of Open Access Journals (Sweden)

    Luis Felipe Salom Serna

    2012-07-01

    Full Text Available El floricultor colombiano no puede desconocer los cambios en tendencias de consumo ni la consolidación del canal retail en su mercado principal, usa.El cuál generará un alto impacto en las características del negocio y el papel de los jugadores en la cadena de suministros. El objetivo de este estudio exploratorio utilizando casos múltiples, es presentar un marco de oportunidades para fortalecer la comercialización de la flor y estructurar canales de distribución acordes a las necesidades del consumidor norteamericano y a los cambios en los hábitos de compra. Las conclusiones, proponen las acciones a emprender por las empresas floriculturas estudiadas a fin de incrementar su competitividad y resolver su dilema actual: contraer oferta para mejorar el precio de venta o incrementar demanda.

  8. Evaluación de conformidad en la calibración del canal de medición de conductividad para aguas farmacéuticas

    Directory of Open Access Journals (Sweden)

    Adolfo Castillo Caballero

    2017-12-01

    Full Text Available Entre los sistemas críticos para la producción de productos inyectables en el Centro de Inmunología Molecular se encuentra el canal de medición de la conductividad, tanto para agua purificada como para el agua para inyección. De acuerdo con el cumplimiento de las Buenas Prácticas de Producción, estos sistemas se someten regularmente a procesos de validación, donde la calibración del canal de conductividad es una práctica obligatoria para la calificación del desempeño. Un equipo o sistema de medición para ser fiable requiere una evaluación de la conformidad, con una probabilidad mayor o igual al 95%. Para dar cumplimiento a los requisitos regulatorios y directrices actuales se propone como criterio la evaluación de la conformidad en la calibración del sistema de agua farmacéutica. Se armoniza el procedimiento de calibración y las regulaciones farmacéuticas internacionales actuales para la medición de la conductividad del agua para productos inyectables. Se definieron las características metrológicas, las fuentes de incertidumbre se cuantifican y se determinan los intervalos de aceptación, para conseguir una probabilidad de la conformidad en la calibración igual al 95% a partir del conocimiento de la capacidad de medición, con el fin de responder a los requerimientos de las agencias regulatorias internacionales para la industria biofarmacéutica.

  9. Late metastasis of breast adenocarcinoma into internal auditory canal and cerebellopontine angle: case report Metástase tardia de adenocarcinoma de mama para o canal auditivo interno e ângulo ponto-cerebelar: relato de caso

    Directory of Open Access Journals (Sweden)

    Edilson Marques

    2002-09-01

    Full Text Available A case of metastasis of breast adenocarcinoma into the internal auditory canal (IAC and cerebellopontine angle (CPA is presented, which appeared 16 years after primary tumor had been treated by surgery and radiation therapy. The 66-year old patient was considered cured from the primary disease, when she started with a rapidly developing hearing loss and intermittent facial palsy. Magnetic resonance image (MRI displayed an intra- and extracanalicular tumor mass, which radiologically resembled a vestibular schwannoma. Surgery was performed and histopathological studies showed an adenocarcinoma compatible with breast origin. Metastasis is a rare occurrence within the IAC and CPA. Clinical history of severe facial palsy will rise suspicion of malignant tumor in spite of the radiological findings.Um caso de metástase de adenocarcinoma de mama para o canal auditivo interno e ângulo ponto-cerebelar é apresentado. A metástase ocorreu após 16 anos do tumor primário ter sido tratado com cirurgia e radioterapia. A paciente de 66 anos foi considerada curada de sua doença primária, quando apresentou perda auditiva de progressão rápida associada a paralisia facial intermitente. Ressonância magnética demonstrou uma lesão expansiva intra e extracanalicular, cujo aspecto radiológico lembrava schwannoma do vestibular. A paciente foi submetida a cirurgia e investigação histopatológica confirmou tratar-se de metástase. Metástase é uma rara ocorrência dentro do canal auditivo interno e ângulo ponto-cerebelar. História clínica de paralisia facial severa aumentará a suspeita de lesão maligna apesar dos achados radiológicos.

  10. Influencia del estrechamiento del canal vertebral y del tiempo para la descompresión en la recuperación locomotora de ratas

    OpenAIRE

    de Souza, Albert Schiaveto; Escobar, Felipe Barros de; Del Bel,Elaine Aparecida

    2009-01-01

    OBJETIVO: o objetivo deste trabalho foi estudar as consequências da lesão por contusão da medula espinhal, associada ao estreitamento do canal vertebral, no comportamento motor de ratos, avaliando-se o efeito do tempo para descompressão na recuperação neurológica dos animais. MÉTODOS: foram utilizados ratos Wistar machos (n=6 por grupo), subdivididos nos seguintes grupos experimentais: laminectomia (T9-T10, Grupo Controle), contusão por queda de peso (10 g de peso, 15 cm de altura), estre...

  11. Módulo de Intervención para abrir canales de Comunicación Asertiva entre Docentes, Padres de Familia y Estudiantes de Secundaria y Media

    OpenAIRE

    Jiménez Suárez, Lina M

    2017-01-01

    La presente investigación se efectúa con la finalidad de determinar de qué manera un módulo de intervención puede abrir canales para la práctica de la comunicación asertiva entre docentes, padres de familia y estudiantes de secundaria y media. La investigación surge a partir de la identificación de las debilidades comunicativas de citados agentes educativos y de los conflictos interpersonales que se desarrolla a partir de esta carencia.  La investigación se efectúa a partir de un enfoque meto...

  12. Modelo para determinar el margen de contribución para cada uno de los centros de distribución, líneas de producto y canales de venta para la empresa Pollo Andino S.A.

    OpenAIRE

    Daza Tovar, Julio César; Hoyos Moreno, Jorge Eduardo

    2014-01-01

    La compañía Pollo Andino S.A. es una empresa del sector avícola con más de 35 años de experiencia en la producción y comercialización de carne pollo en canal en el centro y oriente del país -- Dicho sector se caracteriza por manejar productos con poca diferenciación al considerarse un commoditie, dando como resultado que uno de los puntos más relevantes para que el consumidor tome la decisión de compra sea el precio de venta y no tenga preferencias por una marca específica -- Esta condición d...

  13. Comunicación para América Latina: La propuesta de la Televisión Brasil Canal Integración

    Directory of Open Access Journals (Sweden)

    Maximiliano Martín Vicente

    2009-12-01

    Full Text Available Presenta en tres partes la discusión inicial sobre la propuesta de la Televisión Brasil- Canal Integración en el contexto de la adopción de políticas públicas de reglamentación de los medios de comunicación en el Brasil. En la primera se discute la ausencia de una política de reglamentación, por parte del sector público, sobre los medios de comunicación hasta la modificación de ese procedimiento. En un segundo momento, se habla sobre el papel de las imágenes en la construcción de la realidad y finalmente se muestra la Televisión Brasil- Canal integración como alternativa en el sentido de representar un espacio diferenciado para mostrar la cultura latinoamericana desde una óptica independiente de los grandes medios de comunicación de masas.

  14. Índice de estado limnológico (IEL para evaluar las condiciones ecológicas de las ciénagas del Canal del Dique

    Directory of Open Access Journals (Sweden)

    Vega Mora Leonel

    2010-08-01

    Full Text Available

    Determinar el estado o salud ecológica de un ecosistema brinda herramientas útiles para su gestión y conservación. En Colombia no se han desarrollado índices que combinen en un solo parámetro las variables físicas, químicas y biológicas de los sistemas acuáticos, de manera que la evaluación de su estado ecológico ha sido fragmentaria o incompleta. En este trabajo se presenta el desarrollo de un Índice de Estado Limnológico (IEL para las ciénagas del Canal del Dique, ecosistemas sometidos a constante presión por parte de las comunidades humanas. Para la construcción de este índice multimétrico se realizó un análisis de componentes principales, se construyeron gráficas de calidad de las variables seleccionadas y se les asignaron valores de importancia. Se empleó la teoría de los multiatributos para construir el IEL, el cual considera 12 variables. Se diseñó una versión simplificada (IEL parcial - IELP en la que se excluyeron 4 de las variables biológicas. Finalmente, se construyó una escala de interpretación de los valores obtenidos con estos índices. El IEL y el IELP se aplicaron a las ciénagas del Canal del Dique para establecer su condición ecológica actual. Los datos muestran que el estado limnológico de la mayoría de ciénagas de esta región es aceptable, lo que sugiere que estos ecosistemas lénticos se encuentran dentro de los límites admisibles de funcionamiento, aunque no están excentos de procesos de deterioro.

  15. ÍNDICE DE ESTADO LIMNOLÓGICO (IEL PARA EVALUAR LAS CONDICIONES ECOLÓGICAS DE LAS CIÉNAGAS DEL CANAL DEL DIQUE, COLOMBIA.

    Directory of Open Access Journals (Sweden)

    GABRIEL A. PINILLA A.

    2010-01-01

    Full Text Available Determinar el estado o salud ecológica de un ecosistema brinda herramientas útiles para su gestión y conservación. En Colombia no existen registros de índices que combinen en un solo parámetro las variables físicas, químicas y biológicas de los sistemas acuáticos, de manera que la evaluación de su estado ecológico ha sido fragmentaria o incompleta. En este trabajo se presenta un Índice de Estado Limnológico (IEL para las ciénagas del Canal del Dique, ecosistemas sometidos a constante presión por parte de las comunidades humanas. Para la construcción de este índice multimétrico se elaboraron gráficas de calidad de las variables seleccionadas y se les asignaron valores de importancia. Para construir el IEL se empleó la teoría de los multiatributos considerando 12 variables. También se realizó un análisis de componentes principales de las variables seleccionadas. Se diseñó una versión simplificada (IEL parcial - IELP en la que se excluyeron cuatro de las variables biológicas. Finalmente, se construyó una escala de interpretación de los valores obtenidos con estos índices. El IEL y el IELP se aplicaron a las ciénagas del Canal del Dique para establecer su condición ecológica actual. Los datos muestran que el estado limnológico de la mayoría de ciénagas de esta región es aceptable, lo que sugiere que estos ecosistemas lénticos se encuentran dentro de los límites admisibles de funciona- miento, aunque no están excentos de procesos de deterioro.

  16. Influência do estreitamento do canal vertebral e do tempo para a descompressão na recuperação locomotora de ratos Influencia del estrechamiento del canal vertebral y del tiempo para la descompresión en la recuperación locomotora de ratas The influence of spinal canal narrowing and timing of decompression on locomotion recovery of rats

    OpenAIRE

    Albert Schiaveto de Souza; Felipe Barros de Escobar; Elaine Aparecida Del Bel

    2009-01-01

    OBJETIVO: o objetivo deste trabalho foi estudar as consequências da lesão por contusão da medula espinhal, associada ao estreitamento do canal vertebral, no comportamento motor de ratos, avaliando-se o efeito do tempo para descompressão na recuperação neurológica dos animais. MÉTODOS: foram utilizados ratos Wistar machos (n=6 por grupo), subdivididos nos seguintes grupos experimentais: laminectomia (T9-T10, Grupo Controle), contusão por queda de peso (10 g de peso, 15 cm de altura), estreitam...

  17. canal24

    Data.gov (United States)

    California Department of Resources — Canal system center lines in the Central Valley of California and adjacent areas captured from 1:24,000-scale USGS topographic maps. Updates and modifications made...

  18. Influência do estreitamento do canal vertebral e do tempo para a descompressão na recuperação locomotora de ratos Influencia del estrechamiento del canal vertebral y del tiempo para la descompresión en la recuperación locomotora de ratas The influence of spinal canal narrowing and timing of decompression on locomotion recovery of rats

    Directory of Open Access Journals (Sweden)

    Albert Schiaveto de Souza

    2009-06-01

    Full Text Available OBJETIVO: o objetivo deste trabalho foi estudar as consequências da lesão por contusão da medula espinhal, associada ao estreitamento do canal vertebral, no comportamento motor de ratos, avaliando-se o efeito do tempo para descompressão na recuperação neurológica dos animais. MÉTODOS: foram utilizados ratos Wistar machos (n=6 por grupo, subdivididos nos seguintes grupos experimentais: laminectomia (T9-T10, Grupo Controle, contusão por queda de peso (10 g de peso, 15 cm de altura, estreitamento do canal vertebral em 35% (hastes de policarbonato; espessura de 0,78 mm e contusão associada ao estreitamento do canal vertebral. O grupo de lesão associada foi ainda subdividido em sem ou com descompressão 24 ou 72 horas após a cirurgia. Os animais foram sacrificados sete dias após os procedimentos cirúrgicos. A função locomotora dos animais foi avaliada por meio do teste do campo aberto, do teste do plano inclinado e pela aplicação da escala BBB, antes da cirurgia, 24 e 72 horas depois da cirurgia e após 7 dias do procedimento cirúrgico. RESULTADOS: a lesão por queda de peso e compressão da medula espinhal, bem como a lesão mista, prejudicaram o comportamento motor dos animais, sendo que a descompressão cirúrgica após 24 e 72 horas da cirurgia não melhorou a recuperação motora dos animais, como mostram os resultados da avaliação de campo aberto, no plano inclinado e pela escala BBB. Por outro lado, os animais que sofreram lesão medular por queda de peso apresentaram melhores escores na escala BBB e ângulos maiores no plano inclinado do que aqueles que sofreram lesão por estreitamento do canal vertebral ou lesão mista. CONCLUSÕES: a lesão por queda de peso ou estreitamento do canal vertebral provocou alterações no comportamento motor dos animais, sendo que a descompressão não trouxe melhora funcional significativa.OBJETIVO: estudiar las consecuencias de la lesión por contusión de la médula espinal, asociada al

  19. The effect of using an alternative irrigant between sodium hypochlorite and chlorhexidine to prevent the formation of para-chloroaniline within the root canal system.

    Science.gov (United States)

    Mortenson, D; Sadilek, M; Flake, N M; Paranjpe, A; Heling, I; Johnson, J D; Cohenca, N

    2012-09-01

    To determine if the formation of para-chloroaniline (PCA) can be avoided by using an alternative irrigant following sodium hypochlorite but before chlorhexidine. Fifty-five single-rooted teeth were decoronated, instrumented to size 40, .06 taper whilst being irrigated with 14% ethylene-diamine-tetra-acetic acid (EDTA) and 6% NaOCl. Samples were then randomly divided into three experimental and two control groups. Group 1 was irrigated with saline followed by 2% chlorhexidine gluconate (CHX). Group 2 was irrigated with 50% citric acid (CA) followed by 2% CHX. Group 3 was irrigated with 14% EDTA followed by 2% CHX. The chemical identity and quantification of the PCA in the formed precipitate was determined using gas chromatography/mass spectrometry (GC/MS). All experimental groups contained PCA. The mean level of PCA for group 1 (sterile saline) was 229 ng mL(-1), group 2 (citric acid) 72 ng mL(-1) and group 3 (EDTA) 400 ng mL(-1), respectively. A significant difference was found between the saline and EDTA groups and the negative control (P < 0.05). Although no statistical significance was found between the negative control and citric acid group, PCA was still present in this experimental group. Citric acid used as the intermittent irrigant had the least amount of PCA formation in the canal system. Until the threshold required to cause biological damage in humans is determined, the combination of NaOCl and CHX in root canal treatment should be avoided. © 2012 International Endodontic Journal.

  20. Facebook como canal de comunicación corporativo para organismos y ONG Internacionales acreditados en Colombia

    OpenAIRE

    Navas Charry, Catalina

    2013-01-01

    Las Redes sociales se han convertido en un elemento esencial para la comunicación y el marketing empresarial a nivel mundial. A pesar de su importancia, existen aún muchas organizaciones que no cuentan con dicha herramienta y que prefieren mantenerse fuera del mundo tecnológico y de la web 2.0. El tema que se desarrollará a continuación en este trabajo de grado trata sobre la importancia de usar las redes sociales, en este caso Facebook, como herramienta de comunicación corporativa para t...

  1. Toracotomia minimamente invasiva (miopreservadora para ligadura do canal arterial em prematuros Minimally invasive thoracotomy (muscle-sparing thoracotomy for occlusion of ductus arteriosus in preterm infants

    Directory of Open Access Journals (Sweden)

    Andrey José de Oliveira Monteiro

    2007-09-01

    Full Text Available OBJETIVO: Avaliar a aplicabilidade, segurança e resultados iniciais da toracotomia minimamente invasiva para ligadura do canal arterial em prematuros. MÉTODO: Entre outubro de 1991 e julho de 2003, 273 prematuros e prematuros extremos foram submetidos à ligadura cirúrgica do canal arterial por toracotomia miopreservadora, com anestesia geral, em UTI neonatal. Os dados demográficos pré-operatórios e os desfechos de mortalidade e eventos adversos foram, retrospectivamente, avaliados por meio de consulta aos prontuários. RESULTADOS: Não houve óbito relacionado com o ato operatório e 234 (86% pacientes tiveram alta hospitalar. Os 39 óbitos ocorreram entre o 1º e o 51º dias e foram atribuídos à sepse (14 pacientes, hemorragia intracraniana (11 pacientes e enterocolite necrotizante (nove pacientes, todas causas inerentes à prematuridade. Em cinco pacientes, a causa não foi adequadamente estabelecida. As complicações mais freqüentes relacionadas ao procedimento foram: pneumotórax 3,3% (nove pacientes e hemorragia 1,4% (quatro pacientes. CONCLUSÕES: A técnica de toracotomia minimamente invasiva para a ligadura do canal arterial quando realizada em prematuros e prematuros extremos é aplicável, segura, eficaz, relacionada à baixa morbidade e não depende da estrutura hospitalar local.OBJECTIVES: To analyze the feasibility, the safety, and the primary outcomes of a minimally invasive thoracotomy for the occlusion of ligamentum arteriosum (ductus arteriosus in preterm infants. METHODS: Between October 1991 and June 2003, 273 preterm infants and very low birth weight preterm infants were submitted to a surgical occlusion of the ligamentum arteriosum (ductus arteriosus through muscle-sparing thoracotomy under general anesthesia in the neonatal ICU. Pre-operative demographic data, mortality outcomes, and adverse events were retrospectively analyzed through medical records consultation. RESULTS:There were no deaths related to surgery

  2. Modelización del canal inalámbrico para enlaces punto a punto empleando tecnología Zigbee en entornos exteriores

    Directory of Open Access Journals (Sweden)

    Román Alcides Lara Cueva

    2017-05-01

    Full Text Available En el presente trabajo se realiza el modelización del canal de propagación para una red de comunicación punto a punto (PtP, del inglés Point-To-Point entre dispositivos que utilizan tecnología ZigBee en entornos suburbanos a 2.4GHz, para poder brindar a la comunidad científica encargada de la planificación y dimensionamiento de redes, un modelo ajustado específicamente a redes con estas características que permitirá aumentar la eficiencia y disminuir los costos implícitos de las mismas. El modelo presentado fue obtenido al interpolar las mediciones de la potencia recibida (RSSI, del inglés Received Signal Strength Indicator durante el despliegue de una red PtP de longitud variable de 2 a 160 metros, modificando la altura de los dispositivos en intervalos de 25 centímetros y ajustando las curvas resultantes a modelos matemáticos conocidos. En contraposición a diversos artículos de la literatura, nuestro modelo hace énfasis en el efecto causado por la altura de los dispositivos sobre la distancia a la cual se genera discontinuidad en el modelo de propagación, encontrándose que dicha discontinuidad describe un comportamiento exponencial decreciente donde a medida que la altura aumenta, la discontinuidad se aproxima al transmisor, hasta una distancia límite de 60 metros, a partir de la cual la altura de los dispositivos deja de influir en la distancia donde se produce la discontinuidad.

  3. Quanto a escova deve ser introduzida no canal anal para avaliação citológica mais eficaz? How deep must the brush be introduced in the anal canal for a more effective cytological evaluation?

    Directory of Open Access Journals (Sweden)

    Sidney Roberto Nadal

    2009-01-01

    Full Text Available OBJETIVO: A sensibilidade da citologia anal varia amplamente na literatura, entre 45% e 98%, o que pode ocorrer devido à falta de padronização quanto à distância que a escova deve ser introduzida no canal anal. Desta forma, nosso objetivo foi investigar se o local de coleta influencia no resultado desse exame. MÉTODOS: Colhemos amostras com escova introduzida 4 cm no canal anal de 114 doentes (Grupo A e 2 cm em outros 94 pacientes (Grupo B, antes do exame proctológico. Realizamos cinco rotações com a escova antes de retirá-la e a esfregar sobre lâmina de vidro, posteriormente submetida ao exame citopatológico padrão. Todos os doentes são HIV-positivo. Submetemos os resultados à avaliação estatística. RESULTADOS: No Grupo A, 39 doentes possuíam condilomas no canal anal e a citologia foi positiva em 29 deles (74,3%. Também observamos alterações citológicas em 30 de 75 doentes (40% sem lesões clínicas no canal anal. No Grupo B, havia 54 doentes com condilomas no canal anal e em 13 (24,1% houve confirmação citológica. Em 40 outros, sem lesões clínicas pelo HPV, notamos que em nove (22,5% havia anormalidades citológicas. Os testes estatísticos revelaram que os exames realizados nos doentes do Grupo A foram mais eficientes. CONCLUSÃO: Os espécimes coletados com escovas inseridas mais profundamente no canal anal melhoraram a eficácia do exame.OBJECTIVE: In literature, sensitivity of Pap smears ranges widely from 45 to 98%. Possibly this is because there is no standard for how far the brush should be introduced into the anal canal. The aim was to evaluate whether the sampling site has an influence on the results of anal Pap smears. Design and setting. This is a non-randomized, non-blinded, retrospective review carried out in the Proctology and Pathology Sectors, Emilio Ribas Infectious Diseases Institute. METHOD: We obtained specimens with brushes introduced 4 cm into the anal canal in 114 patients (Group A and 2 cm in

  4. Las implicaciones geopolíticas de la construcción del Canal de Nicaragua para el vecindario del Caribe Occidental (2006-2014)

    OpenAIRE

    Bermúdez Acuña, Camilo Andres

    2016-01-01

    El presente estudio de caso, busca explicar cuáles son las posibles implicaciones e influencia de la construcción del Proyecto del Canal de Nicaragua en la geografía, la economía y la política exterior del Caribe Occidental. Esta investigación defiende que la construcción de este canal influirá en el largo plazo en la geopolítica de esta región, debido a la posibilidad de una competencia hasta hoy inexistente en la región entre dos canales interoceánicos, que puede lleg...

  5. Sealing ability of cements in root canals prepared for intraradicular posts Capacidade seladora de cimentos em canais radiculares preparados para pinos intra-radiculares

    Directory of Open Access Journals (Sweden)

    Dirce Haruko Nakamura

    2006-08-01

    Full Text Available This research evaluated the sealer ability of 2 temporary filling materials (white Cimpat and IRM and 1 restorative cement (glass ionomer, in canals prepared for root posts. Sixty human palatal roots of maxillary first molars were used. They were divided into 3 groups, according to the cements used: Group I (Cimpat, Group II (IRM and Group III (glass ionomer. The roots were rendered impermeable, filled with the respective cements and soon after immersed into 0.2% Rhodamine B dye and maintained for 72 hours in an oven for 37°C. Microleakage was measured with a light microscope, cutting the roots longitudinally in buccolingual direction. The results showed that Group I presented significantly more leakage than Groups II and III, which were not significantly different from each other.Esta pesquisa avaliou a capacidade seladora de dois cimentos temporários (Cimpat branco e IRM e um cimento restaurador em canais preparados para pinos intra-radiculares. Foram usadas 60 raízes palatinas de primeiros molares superiores humanos. Elas foram divididas em 3 grupos, conforme os cimentos usados: grupo I (Cimpat, grupo II (IRM e grupo III (ionômero de vidro. As raízes foram impermeabilizadas, preenchidas com os respectivos cimentos e em seguida imersas em tintura de Rhodamina B a 0,2% e mantidas por 72 horas em uma estufa a 37ºC. A micro infiltração foi mensurada com um microscópio de luz nas raízes cortadas longitudinalmente, na direção vestíbubo-lingual. Os resultados mostraram que o grupo I apresentou, de modo significante, mais infiltração do que os grupos II e III, enquanto que entre estes não houve diferença significante.

  6. El Canal del Atazar I

    Directory of Open Access Journals (Sweden)

    López de Berges y de los Santos, Emilio

    1967-03-01

    Full Text Available The Atazar Canal helps to supply Madrid with water, from the rivers Lozoya, Jarama and Sorbe. The section which operates at present starts at the Torrelaguna dam and finishes at the El Goloso reservoir. Later a further section will be added, from the Atazar dam, on the Lozoya river, to link up with the control dam at Torrelaguna. The canal capacity is 16 m3/sec, and it is 43.47 km long. It has a slope of 4/10.000. The cross section is similar to that of the Jarama canal, already built. There are interconnections between this canal and the Canal Alto, which previously supplied the high and medium part of Madrid. To overcome the ground unevenness 5 syphons have been built, the most important of which is the Colmenar Goloso syphon, which is 10.88 km in length. Construction commenced on December 10, 1962, and water reached Madrid on June 15th, 1966. The initial budget for this project was 1,500 million pesetas.El canal del Atazar refuerza considerablemente el abastecimiento de aguas a Madrid, procedentes de los ríos Lozoya, Jarama y, en un próximo futuro, del Sorbe. El tramo, actualmente en funcionamiento, empieza en el salto de Torrelaguna y finaliza en los depósitos de El Goloso. Más adelante se completará su trazado mediante un nuevo tramo que partirá del embalse de Atazar, en el Lozoya, para unirse al actual en el depósito regulador de Torrelaguna. Su capacidad es de 16 m3/s; su longitud, 43,471 km, y su pendiente, 4 diezmilésimas. La sección tipo es análoga a la del canal del Jarama, de construcción anterior. Mediante la oportuna obra de transvase se realizan intercambios entre este Canal y el Canal Alto que abastecía anteriormente la parte media y alta de la capital. Para salvar los desniveles del terreno se han construido 5 sifones, siendo el más importante el de Colmenar-Goloso, con una longitud de 10,8S4 km. El comienzo de las obras tuvo lugar el 10 de diciembre de 1962, y el agua llegó a Madrid el 15 de junio de 1966. Su

  7. Diseño y conceptualización de un canal de venta virtual como estrategia de comercialización de productos para la compañía Comercantiles Ltda.

    OpenAIRE

    Gallego Zapata, Juan David

    2012-01-01

    Con el fin de potencializar las ventas del portafolio de productos alimenticios funcionales de la compañía Comercantiles Ltda. y aprovechar la actual tendencia mundial en los nuevos esquemas de comercialización, el presente trabajo pretende dar las pautas necesarias para estructurar un canal de ventas online mediante la creación de una Tienda Virtual. Esta propuesta que apuesta a una inversión relativamente baja en conjunto con planes estratégicos de comercio electrónico, le ayudará a la comp...

  8. Desarrollo de un simulador de un sistema LTE para la evaluación del rendimiento del sistema obtenido en canales MIMO

    OpenAIRE

    Ferreras Mayo, Marta

    2016-01-01

    El objetivo de este Trabajo de Fin de Grado es desarrollar un simulador a nivel de enlace, en lenguaje Matlab, que modele el enlace descendente de un canal de comunicaciones móviles LTE (Long Term Evolution), permita configurar múltiples antenas en ambos extremos del canal (Multiple-Input Multiple-Output, MIMO) y dé la posibilidad de seleccionar entre los distintos modos de transmisión estandarizados. El simulador permitirá modelar diversos efectos producidos por fenómenos multitrayecto e...

  9. Canales web en ciencias de la comunicación. Producción multimedia para la docencia e investigación en Documentación informativa

    Directory of Open Access Journals (Sweden)

    Alfonso López Yepes

    2012-04-01

    Full Text Available La creación inicial en una primera fase de un portal de portales de documentación informativa (e-DocuInfo http://multidoc.rediris.es /edocuinfo/  que integra varios portales y posibilita asimismo el acceso a un canal temático de documentación vía internet (TVDoc Complumedia-RTVDoc, juntamente con el funcionamiento de otros dos (E-TV y Cine@Tele Online canal vídeo tienen como objetivo la difusión de contenidos y la generación de una programación en el ámbito documental de las ciencias de la información, de forma distribuida y colaborativa, en estrecha relación con los parámetros de la web 2.0 o web social, y de la Universidad-Empresa. Una segunda fase ha supuesto la producción de numerosos contenidos sistematizados por materias y el establecimiento de verdaderos canales IPTV de emisión total (en consecuencia, TVDoc evoluciona a Complumedia-RTVDoc, y que a su vez plantean la antesala de una tercera fase evolutiva, el establecimiento de una Red iberoamericana de documentación multimedia, ya en ciernes. Estos canales temáticos, que pueden emitir información en tiempo real o en diferido -vídeo bajo demanda-, vehiculan información procedente -en el caso de e-Docuinfo- de la hemeroteca, fonoteca, fototeca, videoteca, en fin, de la mediateca del portal a través de un servidor de streaming. La existencia del portal de portales y de los mencionados canales temáticos web se benefician asimismo, por sus mayores posibilidades de difusión informativa, de la coordinación asumida por el Servicio de Documentación Multimedia (en cuyo ámbito nació e-DocuInfo/TVDoc para el acceso de la facultad de ciencias de la información al campus virtual de la universidad complutense. Y en consecuencia, para su difusión a nivel nacional e internacional, merced a la amplia oferta de posibilidades de las plataformas planteadas para la docencia (semipresencial y virtual, investigación y producción multimedia. La puesta en marcha de canales de este

  10. Efectividad del alcohol absoluto para canalizar los tumores irrresecables de esófago Effectiveness of absolute alcohol to canalize the esophageal non-resectable tumors

    Directory of Open Access Journals (Sweden)

    Juan Carlos Barrera Ortega

    2010-12-01

    Full Text Available INTRODUCCIÓN. En más del 75 % de los pacientes con cáncer de esófago, los procedimientos que se realizan son paliativos y existe un dilema ético sobre la forma de solucionar el problema fundamental: la alimentación. El objetivo de esta investigación fue señalar la importancia de las infiltraciones con alcohol absoluto para lograr la implantación de prótesis esofágicas artesanales por el método de tracción. MÉTODOS. Se realizó un estudio prospectivo y lineal con pacientes con cáncer de esófago irresecable, ingresados entre 1995 y 2009. Fueron evaluados 112 pacientes, de los cuales 65 fueron tratados con métodos paliativos. Se colocaron 55 prótesis esofágicas y en 10 de estos casos fue necesario canalizar previamente el tumor con infiltraciones de alcohol absoluto. RESULTADOS. Se consiguió pasar la sonda nasogástrica en el 90 % de los pacientes que necesitaron infiltraciones de alcohol absoluto. Fueron necesarias entre 1 y 2 sesiones, pero uno de los pacientes necesitó 3 sesiones de infiltración. No hubo complicaciones. CONCLUSIONES. La combinación de alcohol absoluto y prótesis permite eliminar la disfagia en el cáncer avanzado de esófago y cardias. Cuando existe estenosis total, el alcohol absoluto es un método adecuado para canalizar la estenosis tumoral de esófago antes de colocar la prótesis. En la mayoría de los casos son suficientes 1 o 2 sesiones de infiltración.INTRODUCTION. In more than 75% of patients presenting with esophageal cancer the procedures performed are of type palliative and there is a ethical dilemma on the way to solve the major problem: the feeding. The objective of present paper was to emphasize the significance of infiltrations with absolute alcohol to achieve the implantation of handmade esophageal prostheses using the traction method. METHODS. A linear and prospective study was performed in patients presenting with non-resectable esophageal cancer admitted between 1995 and 2009. A total

  11. Atrioventricular Canal Defect

    Science.gov (United States)

    ... tract infections. Atrioventricular canal defect can cause recurrent bouts of lung infections. Heart failure. Untreated, atrioventricular canal ... Leaky heart valves Narrowing of the heart valves Abnormal heart rhythm Breathing difficulties associated with lung damage ...

  12. Estudo anatomotopográfico do canal arterial em fetos natimortos dirigido para sua abordagem por videotoracoscopia Anatomotopographic study of ductus arteriosus in newborn cadavers directed for its videotoracoscopic approach

    Directory of Open Access Journals (Sweden)

    Josué Viana de Castro Neto

    2001-03-01

    Full Text Available Este trabalho objetiva realizar um estudo anatomotopográfico do Canal Arterial em fetos natimortos enfatizando o seu comprimento e seu diâmetro de acordo com o tamanho de cada feto. Além de que, descrevemos as distâncias entre este e pontos de reparo importantes para sua abordagem por videotoracoscopia. Estudamos dezesseis fetos natimortos, sendo que oito eram do sexo masculino. O tamanho do feto e os perímetros torácico e cefálico variaram de 42-57, 26-35 e 29-35,5 cm, respectivamente. A média de comprimento e diâmetro foram 11,06 e 5,56 cm. Distâncias entre o Canal e as seguintes estruturas: clavícula-22,13mm, segunda costela-20,75mm, esterno-33,88mm e a.subclávia esquerda-5,30mm. Acreditamos que as medidas apresentadas podem facilitar a abordagem do canal por videotoracoscopia.The purpose of this work is to realize an anatomic and topographic study of the ductus arteriosus in newborn cadavers emphasizing its lenght and diameter according to each size of the newborn cadaver. We also describe distances between the ductus and important structures for thoracoscopic approach. We study sixteen newborn cadavers. Eight were male. Size of the cadavers, thoracic and cephalic perimeters ranged from 42-47,26-35 and 29-35,5 cm, respectively. Median lenght and diameter were 11,06 and 5,56 mm. Distances between ductus arteriosus and follow structures were: collarbone-22,13mm, second rib-20,75mm, sternum-33,88mm and left subclavian artery-5,30mm. We belived that these distances described can facilitate thoracoscopic surgical approach to the ductus arteriosus.

  13. Lesiones benignas de mama que pueden simular un carcinoma en estudios imagenológicos Benign breast lesions that mimic carcinoma in diagnostic imaging

    OpenAIRE

    Mariana Castro Barba; María Paz Cobos Bombardiere; Flavia Sarquis; Griselda Luna; Bárbara Miller

    2011-01-01

    La mayoría de las lesiones que se encuentran al realizar estudios mamarios son benignas. Muchas de ellas tienen un aspecto típico y definido, ya sea en mamografía o ecografía y no requieren de evaluaciones adicionales. Existe un grupo de entidades benignas que, sin embargo, puede simular un carcinoma en las imágenes. Los radiólogos debemos conocer las características de las mismas y tenerlas en cuenta como posibles diagnósticos diferenciales de una imagen de alta sospecha.Most of the lesions ...

  14. Dispositivo de posicionamiento de muestras biológicas para su irradiación en un canal radial de un reactor nuclear // Biological samples positioning device for irradiations on a radial channel at the nuclear research reactor

    Directory of Open Access Journals (Sweden)

    Maritza Rodríguez - Gual

    2010-05-01

    Full Text Available ResumenPor la demanda de un dispositivo experimental para el posicionamiento de las muestras biológicaspara su irradiación en un canal radial de un reactor nuclear de investigaciones en funcionamiento, seconstruyó y se puso en marcha un dispositivo para la colocación y retirada de las muestras en laposición de irradiación de dicho canal. Se efectuaron las valoraciones económicas comparando conotro tipo de dispositivo con las mismas funciones. Este trabajo formó parte de un proyectointernacional entre Cuba y Brasil que abarcó el estudio de los daños inducidos por diferentes tipos deradiación ionizante en moléculas de ADN. La solución propuesta es comprobada experimentalmente,lo que demuestra la validez práctica del dispositivo. Como resultado del trabajo, el dispositivoexperimental para la irradiación de las muestras biológicas se encuentra instalado y funcionando yapor 5 años en el canal radial # 3(BH#3 Palabras claves: reactor nuclear de investigaciones, dispositivo para posicionamiento de muestras,___________________________________________________________________________AbstractFor the demand of an experimental device for biological samples positioning system for irradiationson a radial channel at the nuclear research reactor in operation was constructed and started up adevice for the place and remove of the biological samples from the irradiation channels withoutinterrupting the operation of the reactor. The economical valuations are effected comparing withanother type of device with the same functions. This work formed part of an international projectbetween Cuba and Brazil that undertook the study of the induced damages by various types ofionizing radiation in DNA molecules. Was experimentally tested the proposed solution, whichdemonstrates the practical validity of the device. As a result of the work, the experimental device forbiological samples irradiations are installed and operating in the radial beam hole #3(BH#3

  15. Sistemas de control para la gestión de los canales de exportación independientes: un análisis exploratorio sobre su diseño y uso

    Directory of Open Access Journals (Sweden)

    Pedro Araujo Pinzón

    2011-08-01

    Full Text Available El empleo de canales de exportación independientes es la forma más extendida de exportación, si bien la ausencia de propiedad dificulta su gestión y afecta al rendimiento exportador. Dado el creciente interés académico y profesional por mejorar la gestión de los procesos de exportación de las empresas y la laguna existente en el estudio de las relaciones inter-organizativas orientadas al mercado (down-stream, se plantea como objetivo del presente estudio la exploración de los sistemas de control de gestión (SCG en el contexto de los canales de exportación, desde la perspectiva de la empresa exportadora. Mediante la realización de un estudio cualitativo exploratorio, se pretende contribuir a la literatura sobre los SCG inter-organizativos ampliando su ámbito de interés a las relaciones down-stream de la cadena de suministros, esenciales para la competitividad de muchas empresas. Frente a estudios previos sobre SCG enfocados en relaciones proveedor-comprador, los resultados muestran que las empresas exportadoras analizadas (1 emplean múltiples mecanismos de control, principalmente cualitativos, que (2 se caracterizan por su ámbito amplio y la oportunidad en el tiempo, así como por sus bajos niveles de integración y agregación, y (3 usan algunos mecanismos -p.e., reuniones con los intermediarios- de modo interactivo, mientras que otras herramientas -p.e., contratos y acuerdos- son usadas de modo diagnóstico. Asimismo, la evidencia sugiere que la definición de sistemas formales en este contexto puede diferir de la tradicional, con amplias repercusiones sobre los marcos de análisis de los sistemas de control de gestión.

  16. Validación y aplicación de un modelo de restauración de manglar basado en individuos para tres especies en la Ciénaga Grande de Santa Marta

    Directory of Open Access Journals (Sweden)

    Jenny Alexandra Rodríguez-Rodríguez

    2016-07-01

    Full Text Available En la década de los años 90 los manglares de la Ciénaga Grande de Santa Marta (CGSM murieron masivamente por los altos niveles de salinidad en el suelo. Este hecho estimuló la reapertura de cinco canales naturales para reducir la salinidad y mejorar las condiciones del bosque (Proyecto PROCIENAGA. Con base en esta experiencia, en 1999 un modelo basado en individuos (FORMAN fue desarrollado para simular trayectorias de restauración del bosque; sin embargo, este modelo fue restringido a un único sitio de la CGSM y a la fecha no había sido probado. Para mejorar su sensibilidad y predictibilidad para simular tendencias del Área Basal (AB de los árboles de Rhizophora mangle, Avicennia germinans y Laguncularia racemosa en este estudio se validó, calibró y ajustó el modelo FORMAN, usando datos de 16 años de monitoreo. Para ello, se modificó la interfaz del modelo y se ajustaron algunas rutinas de cálculo y parámetros. Se ejecutaron dos escenarios de simulación: (1 Asumiendo estabilidad en el intervalo de variación de la salinidad y, (2 aumentado la salinidad de acuerdo con el incremento promedio de los últimos tres años. Los ajustes en las tasas de reclutamiento y salinidad calculada permitieron calibrar el modelo y reproducir el patrón y la magnitud observada en tres estaciones. En dos estaciones solo se reprodujo el patrón de los datos. Las tendencias generales del AB de cada especie y su dinámica, así como las magnitudes actuales para las estaciones que sufrieron mayor impacto inicialmente, fueron reproducidas adecuadamente. Bajo un escenario en el que la salinidad se mantiene en un intervalo estable, el sistema alcanzaría la estabilidad en el largo plazo (>100 años. Un incremento promedio constante en la salinidad intersticial, resultaría en una disminución severa del AB en el corto plazo (menos de 20 años, demostrando la vulnerabilidad de la CGSM a los incrementos en salinidad y la necesidad de implementar medidas de

  17. A study of the time necessary for calcium hydroxide to eliminate microorganisms in infected canals Estudo do tempo necessário para o hidróxido de cálcio eliminar microrganismos em canais infectados

    Directory of Open Access Journals (Sweden)

    Carlos Estrela

    2003-06-01

    Full Text Available The objective of this study was to analyze the time necessary for calcium hydroxide to eliminate microorganisms in infected canals. A total of 168 human anterior teeth were prepared and sterilized. One hundred sixty two teeth were inoculated with suspensions of S. aureus, E. faecalis, P. aeruginosa, B. subtilis, C. albicans. Three teeth were used as negative control and three as positive control. Root canals were irrigated with saline and filled with calcium hydroxide paste (CHP. At intervals of 1 minute, and at 7, 15, 21, 27, 30, 45, 60, and 90 days, CHP was removed, samples were collected and immersed in Letheen Broth (LB. Microbial growth was analyzed by two methods, turbidity of the culture medium and subculture on a Brain heart Infusion. After looking for medium change, an inoculum of 0.1 mL obtained from LB was transferred to 7 mL of Brain Heart Infusion (BHI, and subsequently incubated at 37°C for 48 hours. Microbial growth was checked by turbidity of the culture medium and in some cases by Gram stain. All assays were carried out in triplicate under aseptic technique. The results indicated that the antimicrobial effect on the cultures of S. aureus, E. faecalis, P. aeruginosa, B. subtilis, C. albicans and one mixed culture in infected canals by CHP occurred in 60 days.O objetivo deste estudo foi analisar o tempo necessário para que o hidróxido de cálcio elimine microrganismos em canais infectados. Um total de 168 dentes humanos anteriores foram preparados e esterilizados. Cento e sessenta e dois dentes foram inoculados com suspensões de S. aureus, E. faecalis, P. aeruginosa, B. subtilis e C. albicans. Três dentes foram usados como controle negativo e três como controle positivo. Os canais radiculares foram irrigados com solução fisiológica e preenchidos com pasta de hidróxido de cálcio. Em intervalos de 1 minuto, 7, 15, 21, 27, 30, 45, 60 e 90 dias, a pasta foi removida, amostras foram coletadas e imersas em Letheen Broth. O

  18. Design of canals

    CERN Document Server

    Swamee, P K

    2015-01-01

    The book presents firsthand material from the authors on design of hydraulic canals. The book discusses elements of design based on principles of hydraulic flow through canals. It covers optimization of design based on usage requirements and economic constraints. The book includes explicit design equations and design procedures along with design examples for varied cases. With its comprehensive coverage of the principles of hydraulic canal design, this book will prove useful to students, researchers, and practicing engineers. End-of-chapter pedagogical elements make it ideal for use in graduate courses on hydraulic structures offered by most civil engineering departments across the world.

  19. Diseño del canal de venta a través de Internet para la tienda de calzado MD

    OpenAIRE

    Nave, Ricardo; Rivera, Dinora; Salinas, Duby

    2010-01-01

    Muchos estudios recientes indican un incremento sustancial en el comercio electrónico en América Latina y el Caribe, y muy especialmente en el espacio B2C (Business-to-Customers, relaciones entre negocios y clientes). En el año 2008, las transacciones representaron cerca de USD$16.025 millones, y su crecimiento anual fue casi del 35%. En la región centroamericana, no existen tiendas en la Web que se especialicen en calzado para dama, por lo que una incursión a corto plazo permitiría obtener e...

  20. MCID: personalized dosimetric tool to simulate voxelized studies using MCNP5; MCID: herramienta dosimetrica personalizada para simular estudios voxelizados con MCNP5

    Energy Technology Data Exchange (ETDEWEB)

    Gil, Alex Vergara [Centro de Proteccion e Higiene de las Radiaciones (CPHR), La Habana (Cuba); Perez, Marco A. Coca; Aroche, Leonel A. Torres, E-mail: mcoca@infomed.sld.cu, E-mail: leonel@infomed.sld.cu [Centro de Investigaciones Clinicas (CIC), La Habana (Cuba); Pacilio, Massimiliano, E-mail: mpacilio@scamilloforlanini.rm.it [Hospital S. Camillo Forlanini (AOSCF), Roma (Italy). Departmento de Fisica Medica

    2013-07-01

    The purpose of this paper is to present the MCID software, a tool for calculating specific absorbed dose of patients in nuclear medicine, based on Monte Carlo simulation. This paper evaluates new clinical cases and new phantoms whose results validate the methodology implemented in MCID, which has followed a process of incorporating new materials, image processing in DICOM and Analyze format, a module of regions of interest and improvements in user interface. Now it has a tool to calculate the patient-specific absorbed doses in nuclear medicine that can be applied in clinical practice.

  1. Use of sting-response techniques for simulate diagnostics in human esophagus; Uso de tecnicas estimulo-respuesta para simular diagnosticos en esofago humano

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez, I.; Gonzalez, Y.; Valdes, L.; Alfonso, J.A.; Estevez, E. [Facultad de Quimica Farmacia, Universidad Central de Las Villas (Cuba)

    2003-07-01

    In this work a study of simulation of the gamma graphic studies that are carried out in human esophagus in the Dept. of Nuclear Medicine of the 'Celestino Hernandez Robau Hospital of Santa Clara is presented. For the investigation tubular reactors were used and sting-response techniques with radioactive tracer of Technetium 99 metastable to a concentration of 1 mCi and several flows were applied. The distribution curves of residences times were obtained, those that respond to an equation of the type: Y = A + B exp (- exp((x-C)/D)) - ((x-C/D)+1). They were also carried out, optimizations studies of the doses of the radioactive to give to the patients from 1 mCi (that is the one used in studies) up to 0,5 mCi, and the influences on the obtained distributions of residence time were analyzed. It was confirmed the possibility to lower the doses with clear information of the signal. It was also carried out a simulation of the attenuation of the radiations that takes place in the patients by the interposition of tissues among the analyzed organ, and the detection equipment. It was used paraffin for tissue simulation. It was found the almost independence of the intensity of the radiations with the thickness, for the assayed doses. Lastly it was found a complex mathematical model that responds to the diagnostic curves obtained in these studies, being correlated the coefficients of the pattern with the most important physical parameters of the system, giving it a practical and useful value, all time that the error among the values that this it predicts and the experimental ones do not surpass of 5%. (Author)

  2. El Gobierno Electrónico y la Implementación de las TIC para Brindar Nuevos Canales de Comunicación

    Directory of Open Access Journals (Sweden)

    Rocío Rodríguez

    2015-11-01

    Full Text Available El presente artículo expone la situación actual del gobierno electrónico desde un punto de vista meramente tecnológico, en función del grado de implementación de la tecnología en beneficio de los ciudadanos. No obstante este es un tema amplio que puede ser analizado desde distintas perspectivas y si bien no es el objetivo del artículo realizar una evaluación enfocada a lo social, cultural y político, tampoco nuestro enfoque puede estar completamente aislado de estas cuestiones no menores, que influyen en el momento de tomar decisiones de construir o no, determinada solución tecnológica. En este artículo se plantearan las bases del gobierno electrónico, la evolución histórica y las fases de implementación, para finalmente presentar la situación actual basada en un relevamiento recientemente realizado que dejará en evidencia que aún queda mucho por hacer en materia de gobierno electrónico.

  3. Lesiones benignas de mama que pueden simular un carcinoma en estudios imagenológicos Benign breast lesions that mimic carcinoma in diagnostic imaging

    Directory of Open Access Journals (Sweden)

    Mariana Castro Barba

    2011-03-01

    Full Text Available La mayoría de las lesiones que se encuentran al realizar estudios mamarios son benignas. Muchas de ellas tienen un aspecto típico y definido, ya sea en mamografía o ecografía y no requieren de evaluaciones adicionales. Existe un grupo de entidades benignas que, sin embargo, puede simular un carcinoma en las imágenes. Los radiólogos debemos conocer las características de las mismas y tenerlas en cuenta como posibles diagnósticos diferenciales de una imagen de alta sospecha.Most of the lesions found during breast imaging exams are benign. Many of them have a typical and definite appearance on mammography and ultrasound, and require no further evaluation. However, some benign lesions cannot be differentiated from carcinomas, given their suspicious and less specific radiological features. Radiologists should be aware of the imaging characteristics of these lesions and include them in the differential diagnosis of a malignant-appearing finding.

  4. Relacionamento colaborativo no canal de distribuição: uma matriz para análise Distribution channel relationship: a proposal of an analysis matrix

    Directory of Open Access Journals (Sweden)

    Gessuir Pigatto

    2007-04-01

    Full Text Available Em um mercado cada vez mais dinâmico e turbulento, a habilidade de uma empresa em desenvolver e administrar, com sucesso, seus relacionamentos com outras empresas vem se tornando uma competência necessária que, se bem desenvolvida, pode vir a ser uma fonte de vantagem competitiva sustentável. Neste contexto, fornecedores buscam se adaptar ao aumento do poder de grandes redes varejistas, ao crescimento das centrais de compras, ao fortalecimento das lojas independentes e de demais formatos nos canais de distribuição. Entretanto, essas empresas ainda possuem dificuldade em acompanhar e avaliar os relacionamentos comerciais e, conseqüentemente em adaptá-los a essa nova situação. Assim, o objetivo deste artigo é propor uma matriz de análise que possa avaliar o tipo de relacionamento existente entre agentes comerciais, por meio do acompanhamento dos comportamentos e das ações desenvolvidas por essas empresas. A partir de uma ampla revisão teórica, foram identificadas variáveis presentes em relacionamentos comerciais, como por exemplo, a confiança, o comprometimento, a interdependência, a cooperação, bem como ações e comportamentos que se relacionam ou estão associados a cada uma dessas variáveis. Partindo do pressuposto que a presença de uma ou mais das variáveis em questão sinaliza a possibilidade da existência de diferentes padrões de arranjos entre as empresas, desde o oportunista até o totalmente colaborativo e, utilizando as ações e comportamentos para determinar essa ocorrência, elaborou-se a matriz em questão. Ela é composta por 4 categorias que podem ser utilizadas para classificar o tipo de relacionamento existente entre dois agentes comerciais, dentro de 4 níveis estabelecidos: comportamento tradicional, comportamentos colaborativos, ações colaborativas, e relacionamento colaborativo. Após o desenvolvimento teórico da matriz, optou-se por um teste inicial junto a 10 pares de empresas, redes

  5. Current status of the second generation of parabolic trough solar concentrator for heat generation process designed at the IIE; Estado actual de la segunda generacion del concentrador solar de canal parabolico para generacion de calor de proceso disenado en el IIE

    Energy Technology Data Exchange (ETDEWEB)

    Ramos Berumen, Carlos; Ramirez Benitez, Juan Rafael; Beltran Adan, Jose [Instituto de Investigaciones Electricas, Cuernavaca, Morelos (Mexico)]. E-mail: cramos@iie.org.mx; rramirez@iie.org.mx; jose.beltran@iie.org.mx

    2010-11-15

    The transformation industry normally uses thermal energy within its process, it obtains this energy burning fossils fuel, a new option is to use new technologies like the thermal solar technology like the parabolic trough, this is a long parabolic mirror used to reflect the sunlight and focused on an absorber tube with a heat-conducting fluid inside. The Instituto de Investigaciones Electricas (IIE) developed a prototype of parabolic trough that is operating in different industries, in this article are showing some improvements to the design, giving like result the second generation of the prototype of parabolic trough of the IIE. [Spanish] La industria de la transformacion normalmente utiliza energia termica dentro de su proceso, los medios convencionales para obtener esta energia es el quemar combustibles fosiles, una opcion que aplica nuevas tecnologias es el uso de la tecnologia termosolar a concentracion que le permitira a la industria utilizar el sol como fuente de energia primaria. El uso de esta tecnologia permitira a las empresas generar calor de proceso sin contaminar el ambiente, lo que dara como resultado empresas competitivas y autosuficientes. Para alcanzar temperaturas utiles a estas aplicaciones se requiere concentrar la energia solar en un area mas pequena, siendo la tecnologia mas extendida la de canal parabolico, el principio de operacion de esta tecnologia es la de concentrar la radiacion solar en el eje receptor preparado con una pintura especial para una mejor absorcion del calor y una cubierta de vidrio para evitar perdidas termicas, dentro del tubo circula un fluido caloportador el cual lleva el calor util hacia el proceso. El Instituto de Investigaciones Electricas (IIE) desarrollo un prototipo de canal parabolico, actualmente estan operando en diferentes industrias, resultado de estas aplicaciones se llevo a cabo una evaluacion del prototipo, se detectaron algunos puntos de mejoras al diseno, los cuales se exponen en este articulo, dando

  6. COMSOL Multiphysics para la simulación de propiedades dieléctricas y térmicas en estado estacionario de aceites de transformadores de potencia.

    OpenAIRE

    Barroso Cuerdo, Juan

    2017-01-01

    El objeto principal del presente proyecto es simular en COMSOL Multiphysics comportamientos dieléctricos del aceite del transformador. Los objetivos particulares de este proyecto son: 1. Hacer una revisión de los principales componentes constructivos, principalmente de sus aislantes líquidos, que conforman un transformador de potencia. 2. Simular en COMSOL Multiphysics el comportamiento dieléctrico del aceite de un transformador. Para ello, se establecerá una guía con los pasos a ...

  7. Bilateral bifid mandibular canal

    Directory of Open Access Journals (Sweden)

    Mahnaz Sheikhi

    2012-01-01

    Full Text Available One of the normal interesting variations that we may encounter in the mandible is bifid mandibular canal. This condition can lead to difficulties when performing mandibular anesthesia or during extraction of lower third molar, placement of implants, and surgery in the mandible. Therefore diagnosis of this variation is sometimes very important and necessary.

  8. Depurador de programas y kit de desarrollo para el microcontrolador DS5000T

    OpenAIRE

    González González, Fabio; Moreno Flores, César; Montalvo Ramírez, Luis

    2007-01-01

    Se presenta la realización de un depurador de programas y un kit de desarrollo para el microcontrolador DS5000T. El conjunto de estas herramientas es capaz de simular, ejecutar en forma controlada y cargar serialmente un programa para dicho microcontrolador mediante la utilización de un computador personal IBM o compatible. El depurador fue desarrollado en forma modular utilizando el lenguaje Assembly del microcontrolador i8086.

  9. Sistemas de control para la gestión de los canales de exportación independientes: un análisis exploratorio sobre su diseño y uso

    Directory of Open Access Journals (Sweden)

    Maria Velez Elorza

    2011-12-01

    Full Text Available El empleo de canales de exportación independientes es la forma más extendida de exportación, si bien la ausencia de propiedad dificulta su gestión y afecta al rendimiento exportador. Dado el creciente interés académico y profesional por mejorar la gestión de los procesos de exportación de las empresas y la laguna existente en el estudio de las relaciones inter-organizativas orientadas al mercado (down-stream, se plantea como objetivo del presente estudio la exploración de los sistemas de control de gestión (SCG en el contexto de los canales de exportación, desde la perspectiva de la empresa exportadora. Mediante la realización de un estudio cualitativo exploratorio, se pretende contribuir a la literatura sobre los SCG inter-organizativos ampliando su ámbito de interés a las relaciones down-stream de la cadena de suministros, esenciales para la competitividad de muchas empresas. Frente a estudios previos sobre SCG enfocados en relaciones proveedor-comprador, los resultados muestran que las empresas exportadoras analizadas (1 emplean múltiples mecanismos de control, principalmente cualitativos, que (2 se caracterizan por su ámbito amplio y la oportunidad en el tiempo, así como por sus bajos niveles de integración y agregación, y (3 usan algunos mecanismos -p.e., reuniones con los intermediarios- de modo interactivo, mientras que otras herramientas -p.e., contratos y acuerdos- son usadas de modo diagnóstico. Asimismo, la evidencia sugiere que la definición de sistemas formales en este contexto puede diferir de la tradicional, con amplias repercusiones sobre los marcos de análisis de los sistemas de control de gestión.Independent export channels are the most common exporting entry mode, although the lack of ownership hinders their management and affects export performance. Given the growing academic and professional interest to improve export processes’ management and the existent gap in the study of down-stream inter

  10. Estudio del acceso inicial para redes de ondas milimétricas autónomas y desarrollo de un simulador OFDM para la caracterización del canal

    OpenAIRE

    Lozano Puente, María

    2017-01-01

    El proyecto consiste en el estudio del acceso inicial a una celda en un sistema de comunicaciones celular FDD OFDM, en presencia de beamforming, a frecuencias milimétricas. El escenario se basa en un terminal de usuario, equipado con una sola antena de transmisión/recepción; y una estación base, equipada con un array de antenas bidimensional de transmisión/ recepción con MIMO masivo para compensar parcialmente las pérdidas de propagación, y en el que es necesario llevar a cabo un beamforming...

  11. Anal cancer; Cancer du canal anal

    Energy Technology Data Exchange (ETDEWEB)

    Fesneau, M.; Champeaux-Orange, E. [Service de radiotherapie, Centre regional universitaire de cancerologie Henry-S.-Kaplan CHU de Tours, Hopital Bretonneau, 37 - Tours (France); Champeaux-Orange, E. [Service d' oncologie-radiotherapie, Centre hospitalier regional d' Orleans, 45 - Orleans (France); Hennequin, C. [Service de cancerologie-radiotherapie, hopital Saint-Louis, 75 - Paris (France)

    2010-07-01

    Anal canal epidermoid carcinomas represent 1.2% of digestive cancers and 6% of ano-rectal cancers. For localized diseases, the treatment is based on radiotherapy with or without chemotherapy (5-FU and cisplatin or mitomycin), according to tumour and nodal extension. The recommended treatment dose is 45 Gy in the anal canal, the mesorectum, para-rectal lymph nodes, and inguinal lymph nodes. An additional dose of 15 to 20 Gy is delivered in the initial tumour for good responders. Salvage surgery is necessary in case of poor response. The organs at risk to be considered are bladder, femur heads, small intestine and vulva. The objective of this work is to summarize the epidemiological and radio-anatomic and prognostic characteristics of this tumour. The conformal radiotherapy technique is illustrated by a case report. (authors)

  12. Managing curved canals

    Directory of Open Access Journals (Sweden)

    Iram Ansari

    2012-01-01

    Full Text Available Dilaceration is the result of a developmental anomaly in which there has been an abrupt change in the axial inclination between the crown and the root of a tooth. Dilaceration can be seen in both the permanent and deciduous dentitions, and is more commonly found in posterior teeth and in maxilla. Periapical radiographs are the most appropriate way to diagnose the presence of root dilacerations. The controlled regularly tapered preparation of the curved canals is the ultimate challenge in endodontics. Careful and meticulous technique will yield a safe and sufficient enlargement of the curved canals. This article gives a review of the literature and three interesting case reports of root dilacerations.

  13. Canal plane dynamic visual acuity in superior canal dehiscence.

    Science.gov (United States)

    Janky, Kristen L; Zuniga, M Geraldine; Ward, Bryan; Carey, John P; Schubert, Michael C

    2014-06-01

    1) To characterize normal, horizontal active dynamic visual acuity (DVA) and passive canal plane head thrust DVA (htDVA) across ages to establish appropriate control data and 2) to determine whether horizontal active DVA and passive canal plane htDVA are significantly different in individuals with superior canal dehiscence syndrome (SCDS) before and after surgical repair in the acute (within 10 d) and nonacute stage (>6 wk). Prospective study. Tertiary referral center Patients diagnosed with SCDS (n = 32) and healthy control subjects (n = 51). Surgical canal plugging on a subset of patients. Static visual acuity (SVA), active horizontal DVA, and canal plane htDVA. Visual acuity (SVA, active DVA, and htDVA) declines with age. In SCDS, SVA and active DVA are not significantly affected in individuals after surgical canal plugging; however, htDVA in the plane of the affected canal is significantly worse after canal plugging. Age-based normative data are necessary for DVA testing. In SCDS, htDVA in the plane of the affected canal is normal before surgery but permanently reduced afterward.

  14. Distributed control at Love canal

    Energy Technology Data Exchange (ETDEWEB)

    McPherson, G.; Rider, G.J.; Sadowski, B.; Moore, M.

    1994-09-01

    Love Canal is known worldwide as the site of one of the worst non-nuclear environmental disasters in modern history. For 12 years, a Niagara Falls, New York chemical company used the canal bed as a chemical dump. This article discusses the computerized control of equipment used to remove the toxic materials from the ground under Love Canal, and how the minimization of maintenance is reducing maintenance costs and increasing operator safety.

  15. Analysis of sedimentation of canals

    Directory of Open Access Journals (Sweden)

    Agunwamba, J.C.,

    2013-03-01

    Full Text Available The dredged canals in the Niger Delta coastal flood plain are being threatened by siltation. This study is limited to those canals in Rivers State of Nigeria, which are under the influence of tidal waves. A total of eight canals were considered with four each from Ekulama and Cawthorne Channel. Different approaches were used to carry out this study, which includes field reconnaissance survey, hydrographic survey, soil sample analysis and collection of all available data and information. The typical bed materials size (D50 is approximately 0.01mm; which gives a settling velocity of 0.09mm/sec using stroke’s law. Hydrographic survey of the canals from 1992 to 1996 revealed an average siltation rate of 2.35m/yr. A regression equation was also derived which relates the cost of dredging to canal area, rate of siltation and average aggregation. A plot of canal centre profile; entrance, middle and end cross sections showing sediment distribution along the canal profile, shows that majority of the particles that form the sediment enter the canal from the rivers. The sedimentation is caused by the reduction in water current, which has average value of 0.0145m/sec. The bathyorographical check on the canals revealed that the sum of the two exterior angles of the canal with the river at the point of connection has to lie within 1800 + 50 for an effective flow that will minimize settlement of particles. In addition, the canals should be constructed to start and terminate on a moving water body, to avoid dead ends. A regression equation was determined which relates the cost of dredging to canal area, rate of siltation and average aggradations.

  16. Lumbar canal stenosis.

    Science.gov (United States)

    Mazanec, D J; Drucker, Y; Segal, A M

    1997-04-01

    Lumbar canal stenosis is an increasingly recognized condition in patients more than 65 years of age. The clinical syndrome is dominated by neurogenic claudication. The natural history of the Condition is not yet well described. Long-term results of surgical therapy are frequently disappointing, and reoperation is required in more than 10% of patients. Nonoperative treatment options include physical therapy exercise programs, calcitonin, analgesics, and epidural steroid injections. A clinical pathway for management of symptomatic stenosis, emphasizing an initial nonoperative approach, is suggested.

  17. Aspectos biofarmacêuticos da formulação de medicamentos para neonatos: fundamentos da complexação de indometacina com hidroxipropil-beta-ciclodextrina para tratamento oral do fechamento do canal arterial Biopharmaceutical aspects of drug formulation for neonatology: rational for indomethacin's complexation with hydroxypropyl-beta-cyclodextrin to treat patent ductus arteriosus

    Directory of Open Access Journals (Sweden)

    Ana Cristina Ribeiro Rama

    2005-09-01

    Full Text Available A terapêutica farmacológica em recém-nascidos confronta-se, por um lado, com um organismo sujeito a marcadas alterações biológicas, resultantes da composição orgânica e da maturação funcional, que decorre a diferentes graus em crianças com a mesma idade, determinando modificações no perfil farmacocinético e farmacodinâmico e, por outro lado, com a necessidade efetiva da utilização de fármacos. Para dar resposta à necessidade de tratamento destes doentes, recorre-se à utilização de medicamentos "off label", sendo esta uma prática com um elevado risco de segurança e de eficácia, na ausência de informação acerca da estabilidade, solubilidade e biodisponibilidade. Considerou-se, assim, que a utilização de derivados das ciclodextrinas altamente solúveis em água seria uma alternativa para a formulação de preparações líquidas aquosas de fármacos fracamente solúveis, aliada à melhoria de biodisponibilidade e de segurança. Esta revisão pretende fundamentar a possibilidade de recurso à complexação de indometacina com hidroxipropil-beta-ciclodextrina, com o objetivo de melhorar as características de biodisponibilidade e de segurança e permitir a administração por via oral para o tratamento farmacológico do fechamento do canal arterial em prematuros ou em recém-nascidos com esta patologia.Pharmacological therapy for newborns is faced on one hand, with an organism characterized by biological differences and functional immaturity with various grades of evolution for the same age, implying changes on the pharmacokinetic and pharmacodinamic medicine profiles. On the other hand, there is the effective need for pharmacotherapy. The "off label" use of medicines is therefore the only thing left to do, having in mind the risk of using therapeutic agents not studied for this special group of people. On this context it has been considered the use of cyclodextrin derivatives like hydroxypropyl-beta-cyclodextrin as an

  18. Mejoras en el canal de Panamá

    Directory of Open Access Journals (Sweden)

    Brandl, Charles McG.

    1963-07-01

    Full Text Available The Panama Canal, together with the Suez Canal, is an engineering accomplishment which is now regarded as a master work marking the initiation of modern civil engineering. Other projects, also of great magnitude, do not seem to maintain the reputation of the above two, because they cannot continue to serve their function with sustained usefulness in the new circumstances of today. The Panama Canal, with its limited dock capacity, and the narrow, so called Serpent, canal, has had to cope with a continuously increasing volume of shipping traffic; a natural consequence of commercial evolution. In order to keep up with these increasing demands, it has been necessary to carry out an almost uninterrupted series of modifications and improvements, affecting both the method of operation and organisation, and the actual nature of the canal. Thanks to these alterations the Panama Canal has continued to maintain, at least nominally, an adequate standard of functional efficiency. At present the canal is being widened over certain sections to enable the easy passage of ships of great displacement. The work is being done very rapidly, and in order to gain time, it has been distributed to various contractors simultaneously.El canal a través del ismo de Panamá es una obra de ingeniería civil que, junto con el de Suez, empiezan ya a clasificarse como obras maestras que señalan el primer jalón del desarrollo de la ingeniería moderna. Otras obras, también importantes, no conservan, sin embargo, la misma reputación que aquéllas, por no seguir un paralelismo con las exigencias en cada época. El canal de Panamá, con sus exclusas, y angosto paso llamado de la. Culebra, ha tenido que afrontar un tráfico creciente de navíos que siguen la evolución del tiempo. Para conseguir este paralelismo, tanto el material de explotación como la organización, dragados y mejoras, han tenido que conocer una sucesión ininterrumpida de modificaciones que han permitido

  19. Low-intensity laser coupled with photosensitizer to reduce bacteria in root canals compared to chemical control; Laser em baixa intensidade associado a fotosensibilizador para reducao bacteriana intracanal comparado ao controle quimico

    Energy Technology Data Exchange (ETDEWEB)

    Garcez Segundo, Aguinaldo Silva

    2002-07-01

    The photodynamic therapy is a process in which a dye is associate with an appropriate wavelength of light and this dye goes to an excited state. The excited reacts with oxygen to form the highly reactive compound singlet oxygen, and this compound can kill bacteria and tumor cells. The purpose of this study was to evaluate the bactericidal reduction in root canal contaminated with E. Faecalis. Thirty teeth with their root canals prepared were contaminated with E. faecalis. The teeth have received the chemical substance sodium hypochlorite for 30 minutes; ten teeth have received the azulene dye paste for 5 minutes and have been irradiated with a diode laser, output power 10 mW and {lambda}= 685 nm for 3 minutes. Ten teeth have not received treatment (control group). The bacterial reduction was significantly higher for laser group when compared to chemical and control groups. These results indicate photodynamic therapy as an effective method to kill bacteria. (author)

  20. Spinal canal stenosis; Spinalkanalstenose

    Energy Technology Data Exchange (ETDEWEB)

    Papanagiotou, P.; Boutchakova, M. [Klinikum Bremen-Mitte/Bremen-Ost, Klinik fuer Diagnostische und Interventionelle Neuroradiologie, Bremen (Germany)

    2014-11-15

    Spinal stenosis is a narrowing of the spinal canal by a combination of bone and soft tissues, which can lead to mechanical compression of spinal nerve roots or the dural sac. The lumbal spinal compression of these nerve roots can be symptomatic, resulting in weakness, reflex alterations, gait disturbances, bowel or bladder dysfunction, motor and sensory changes, radicular pain or atypical leg pain and neurogenic claudication. The anatomical presence of spinal canal stenosis is confirmed radiologically with computerized tomography, myelography or magnetic resonance imaging and play a decisive role in optimal patient-oriented therapy decision-making. (orig.) [German] Die Spinalkanalstenose ist eine umschriebene, knoechern-ligamentaer bedingte Einengung des Spinalkanals, die zur Kompression der Nervenwurzeln oder des Duralsacks fuehren kann. Die lumbale Spinalkanalstenose manifestiert sich klinisch als Komplex aus Rueckenschmerzen sowie sensiblen und motorischen neurologischen Ausfaellen, die in der Regel belastungsabhaengig sind (Claudicatio spinalis). Die bildgebende Diagnostik mittels Magnetresonanztomographie, Computertomographie und Myelographie spielt eine entscheidende Rolle bei der optimalen patientenbezogenen Therapieentscheidung. (orig.)

  1. Complete atrioventricular canal

    Directory of Open Access Journals (Sweden)

    Limongelli Giuseppe

    2006-04-01

    Full Text Available Abstract Complete atrioventricular canal (CAVC, also referred to as complete atrioventricular septal defect, is characterised by an ostium primum atrial septal defect, a common atrioventricular valve and a variable deficiency of the ventricular septum inflow. CAVC is an uncommon congenital heart disease, accounting for about 3% of cardiac malformations. Atrioventricular canal occurs in two out of every 10,000 live births. Both sexes are equally affected and a striking association with Down syndrome was found. Depending on the morphology of the superior leaflet of the common atrioventricular valve, 3 types of CAVC have been delineated (type A, B and C, according to Rastelli's classification. CAVC results in a significant interatrial and interventricular systemic-to-pulmonary shunt, thus inducing right ventricular pressure and volume overload and pulmonary hypertension. It becomes symptomatic in infancy due to congestive heart failure and failure to thrive. Diagnosis of CAVC might be suspected from electrocardiographic and chest X-ray findings. Echocardiography confirms it and gives anatomical details. Over time, pulmonary hypertension becomes irreversible, thus precluding the surgical therapy. This is the reason why cardiac catheterisation is not mandatory in infants (less than 6 months but is indicated in older patients if irreversible pulmonary hypertension is suspected. Medical treatment (digitalis, diuretics, vasodilators plays a role only as a bridge toward surgery, usually performed between the 3rd and 6th month of life.

  2. Desarrollo de algoritmos para la selección de canales espectrales en redes inalámbricas de radio cognitiva usando las estrategias rectiva y proactiva - Development of algorithms for the selection of spectral channels in wireless cognitive radio networks using rective and proactive strategies

    Directory of Open Access Journals (Sweden)

    Danilo Alfonso López-Sarmiento

    2017-05-01

    Full Text Available La Radio Cognitiva (CR es el paradigma que permite optimizar la eficiencia del espectro radio eléctrico a través de una gestión dinámica basado en el sensado, decisión, compartición y movilidad espectral, siendo la toma de decisiones la encargada de la selección del mejor/mejores canales para la transmisión de los datos de los nodos cognitivos (SUs, dependiendo de la calidad de servicio solicitada (Best Effort (BE o Real Time (RT. La literatura existente plantea implícitamente la utilización de una estrategia reactiva para la selección de dichas bandas; no obstante, ello implica que las solicitudes de los SUs solo se procesarán una vez arriben a la estación base (BS de la red cognitiva, generando retrasos adicionales en el envío de los datos. En el presente artículo se plantea el uso de la estrategía proactiva planteada en [1], pretendiendo con ello que el procesamiento de las solicitudes de asignación de espectro para los SUs se realice de manera más rápida o eficiente (tiempo menor de procesamiento en la estación base (BS, con ello optimizando la etapa de decisión espectral en CR.  Los resultados demuestran que el sistema proactivo reduce el tiempo de asignación de canales a los SUs sin degradar la comunicación del PU.

  3. Metodologia para o monitoramento da difusão de inovação em canais de comunicação científica Metodología para el seguimiento de la difusión de la innovación en canales de comunicación científica

    Directory of Open Access Journals (Sweden)

    Patricia Zeni Marchiori

    2012-10-01

    Full Text Available Introdução: a difusão da inovação em produtos/tecnologias se apoia no uso de diferentes canais de comunicação. As adaptações/aperfeiçoamentos veiculados entre os participantes destes canais podem ser agregadas em categorias de acordo com condições de adoção (existente, proativa, aspiracional, reativa. O monitoramento e a visualização de tais condições permitiria explorar o estado da arte da inovação e acompanhá-lo em ciclos de tempo definidos e/ou alcance geográfico para um determinado canal e/ou entre canais distintos. Objetivos: propõe-se uma metodologia de monitoramento da difusão da inovação em canais de comunicação científica e suas respectivas condições de adoção. Procedimentos metodológicos: explora-se a Teoria da Difusão da Inovação e o modelo conceitual dela derivado. Descreve-se a metodologia proposta em suas etapas qualitativa e quantitativa e apresenta resultados de teste de aplicação em um recorte de comunicações apresentadas em edições de eventos internacionais e nacionais relativos ao Sistema Eletrônico de Editoração de Revistas/Open Jornal System. Principais resultados: Aplicada aos corpora do ambiente de teste a metodologia proposta resultou na criação de vinte e nove categorias relacionadas às condições de adoção da inovação e na geração de gráficos provenientes das manipulações de três matrizes de correlação no software UCINET 6.434. Analisaram-se os gráficos obtidos no Netdraw com base em multidimensional scaling (MDS e em frequências absolutas. Conclusões: validou-se a metodologia no ambiente teste, com destaque aos alertas para a execução das etapas e nas possibilidades de análise dos dados com o uso de diferentes variáveis. Considera-se que o acompanhamento, se realizado periodicamente, pode identificar tendências e/ou predição da inovação como atividade fim do monitoramento.

  4. Melanoma de canal anal simulando doença hemorroidária: relato de caso Melanoma of the anal canal simulating hemorrhoidal disease: case report

    Directory of Open Access Journals (Sweden)

    Lorena Reuter Motta Gama

    2010-09-01

    Full Text Available O Melanoma Anorretal é um tumor maligno raro com a possibilidade de simular uma doença anorretal, tornando o diagnóstico difícil. Tem baixos índices de cura e elevados índices de mortalidade em curto prazo. Os autores descrevem um caso de melanoma de canal anal cuja interpretação por parte do paciente tratava-se de uma doença hemorroidária que exteriorizava às evacuações. Os autores fazem uma extensa revisão da literatura dando ênfase aos sintomas e a melhor opção terapêutica a ser instituída.Anorectal melanoma is a rare malignant tumor with the small chance of simulating anorectal disease, making the diagnosis hard. There is a low rate of cure and high rate of short term mortality. The authors describe a case of anal melanoma which by the patient's interpretation was hemorrhoid disease that exteriorized evacuations. The authors do an extensive evaluation of the literature, giving emphasis to the symptoms and the best therapeutic option to be used.

  5. Historia de los medios de comunicación de Misiones: LT 85 TV Canal 12, el canal de TV de los Misioneros. 16H295

    OpenAIRE

    Alvarez, Norma G., dir.; Pyke, Jorge N.; Garcia Da Rosa, Carlos A; Pernigotti, Gilda; Milton, Terencio; Lima,Roberto

    2010-01-01

    Actividades desarrolladas durante el período: avance en la búsqueda de información respecto de documentación y de fuentes orales de información sobre la historia del Canal 12; rescate testimonios fotográficos y de cintas fílmicas de los primeros años del Canal 12 que están en poder de particulares; rescate de material fílmico existente en el Canal; desgravaciones de las entrevistas realizadas para la entrega posterior a los informantes. Sistematización de la organización de las fotografías qu...

  6. El fomento ilustrado. Un ejemplo significativo: el Canal de Castilla

    OpenAIRE

    Benito Martín, José María

    2016-01-01

    El Canal de Castilla es la obra de ingeniería hidráulica más importante y de mayor envergadura que se llevó a cabo en España durante la Época Moderna. A través del desarrollo de la historia del Canal se analizará la repercusión económica de la región castellana y su importancia tanto a nivel cultural como patrimonial. El Canal representaría la vía fluvial de comunicación entre Castilla y el mar del norte para transportar los excedentes de cereales a otros países y al propio, siendo años de gr...

  7. Hood Canal Steelhead - Hood Canal Steelhead Supplementation Experiment

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Hood Canal Steelhead Project is a 17-year before-after-control-impact experiment that tests the effects of supplementation on natural steelhead populations in...

  8. Compressão segmentar do plexo venoso extra-raquidiano: Valor para o diagnóstico de localização das afecções bloqueantes do canal raquidiano

    Directory of Open Access Journals (Sweden)

    Oswaldo Ricciardi Cruz

    1959-09-01

    Full Text Available Outside and inside the vertebral canal, running along its entire length, there is a series of venous plexuses which anastomoses with each other and end in intravertebral veins. They form a real plexuses whose primary disposition is schematically segmental. The plexuses form a series of venous rings at the level of each vertebra. Considering these anatomic data it has been supposed that a strong and lengthened compression at the level of the outside venous plexus will cause a raise in the inside venous pressure which can be detected with a Strauss manometer connected with a needle inserted in the lumbar subarachnoid space. The test would be indicated to locate the lower level of the spinal canal block by the oscilations of the cerebrospinal fluid pressure registered under this level. The test was performed in 5 patients without blocking process in which the Stookey test was normal; in none these cases it was found any raise in the cerebrospinal fluid pressure by local compression of venous plexuses of the spine from cervical untill lumbar vertebrae. The procedure was applied to 5 patients with blocking conditions of the spinal canal, previously diagnosed by the Stookey test. In 4 of these a definite increase (2 to 10 cm. of the cerebrospinal fluid pressure has been recorded; in these cases the procedure allowed the exact detection of the lower level of the block, later confirmed by myelography and neurosurgery. In one case, however, the test has detected a level that could not be confirmed by myelography or the surgical act.

  9. Metodología para la elaboración de canales endémicos y tendencia de la notificación del dengue, Valle del Cauca, Colombia, 2009-2013

    Directory of Open Access Journals (Sweden)

    Mauricio Hernández

    2016-08-01

    Conclusión. La elaboración del canal endémico del dengue en el Valle del Cauca evidenció la importancia de aplicar estas metodologías de vigilancia en las situaciones de interés en salud pública. Como se observó en los resultados, hubo años en los que el número de casos fue muy bajo y otros en los que la epidemia alcanzó cifras muy elevadas.

  10. Method for Constructing Standardized Simulated Root Canals.

    Science.gov (United States)

    Schulz-Bongert, Udo; Weine, Franklin S.

    1990-01-01

    The construction of visual and manipulative aids, clear resin blocks with root-canal-like spaces, for simulation of root canals is explained. Time, materials, and techniques are discussed. The method allows for comparison of canals, creation of any configuration of canals, and easy presentation during instruction. (MSE)

  11. Efectividad de los canales de búsqueda de empleo 2.0 que utilizan los egresados de maestrías de la Universidad Icesi y su relación con los canales utilizados por las empresas para reclutar talento humano

    OpenAIRE

    Jaramillo Marín, Sandra

    2014-01-01

    En los inicios de la internet en los años sesenta, nació la web 1.0, esta red era solamente informativa, las páginas web solo nos ofrecían contenido de texto y no se podía interactuar, responder o informar algún tema si no se era un experto en programación o en código HTML. A partir del año 2004 la revolución digital lanzó la web 2.0, creando canales de interacción entre contactos. Las personas y empresas pueden publicar y difundir su propia información y generar conocimiento a otros conta...

  12. Looking back at Love Canal

    Energy Technology Data Exchange (ETDEWEB)

    Deegan, J. Jr.

    1987-05-01

    In the first part of this series (ES and T, April 1987, pp. 328-31) it was pointed out that the methods and conclusions of EPA's Love Canal Study were the subject of some controversy in the environmental community. Others defended the agency's approaches and methods. Part 2 makes no attempt to resolve the controversy; its purpose is to present the results and conclusions of the Love Canal.

  13. Control amb DSP d’un motor de corrent continu per simular càrregues mecàniques per a una nova plataforma docent de control de màquines elèctriques

    OpenAIRE

    Ortiz Verdura, Xavier

    2006-01-01

    Actualment, el control de motors és una aplicació de gran importància tant en el món industrial com en el domèstic. Per aquest motiu és interessant fomentar l’educació en aquest camp. A més, degut a la ràpida evolució d’aquesta tecnologia, no hi ha gaire material didàctic en el mercat. D’aquesta manera el present projecte pretén desenvolupar un control amb DSP d’un motor de corrent continu per tal de simular càrregues mecàniques per a una nova plataforma docent. Així doncs, servirà per com...

  14. RETRATAMENTO ENDODÔNTICO: ESTUDO COMPARATIVO ENTRE TÉCNICA MANUAL, ULTRA-SOM E CANAL FINDER ENDODONTIC RETREATMENT: COMPARATIVE STUDY BETWEEN MANUAL TECHNIQUE, ULTRASONIC SCALER, AND CANAL FINDER

    Directory of Open Access Journals (Sweden)

    Clovis Monteiro BRAMANTE

    1998-01-01

    Full Text Available Instrumentações manual, ultra-sônica e com Canal Finder foram utilizadas para retratamento de 30 dentes com canais obturados com guta-percha e óxido de zinco e eugenol. Avaliaram-se: 1. tempo gasto para a penetração inicial até o ápice; 2. tempo para completar a limpeza; 3. extrusão de material e 4. limpeza dos canais. O Canal Finder foi a técnica que propiciou melhor limpeza, seguida da manual e da ultra-sônica. A parede palatina do canal foi constantemente mais limpa do que a vestibular. Quanto à extrusão, a técnica de ultra-som foi a que propiciou mais extravasamento de material obturador.Endodontic retreatment of 30 teeth filled with guta percha and zinc oxide-eugenol was carried out using manual instrumentation, ultrasonic scaler, and the Canal Finder System. The following variables were evaluated: time spent to reach the apex; time spent to complete cleaning of the canal; apical extrusion of material; and cleanliness of the canals. Results showed the Canal Finder System as providing the highest level of cleanliness of the canal system; lingual walls were constantly cleaner than buccal walls; ultrasonic technique presented a greater degree of apical extrusion of filling material.

  15. Hidrotransporte de pulpa de papel en un canal abierto de sección circular

    OpenAIRE

    Hernán Javier Gómez Zambrano

    2009-01-01

    Este artículo presenta los resultados de la investigación experimental llevada a cabo sobre el transporte hidráulico de mezclas en canales abiertos. Se investigó acerca de las mezclas no sedimentables compuestas de pulpa de papel y agua en un canal abierto de sección transversal circular. El objeto de la investigación fue determinar las pérdidas de energía debido al flujo de agua y pulpa de papel, a fin de proponer una metodología para el diseño de canales abiertos a mezclas. A causa del desa...

  16. SICOMPC: SIMULADOR PARA CONTROL PREDICTIVO BASADO EN MODELOS

    Directory of Open Access Journals (Sweden)

    ROBIN SALCEDO

    2008-01-01

    Full Text Available En este artículo se describe la herramienta computacional SICOMPC desarrollada con el fin de poder disponer de un programa para simulación de control predictivo basado en modelos. Si bien existen en el mercado algunos programas dedicados al control predictivo, ellos son en su mayoría costosos y de estructuracerrada. SICOMPC de otro lado tiene una estructura modular e incluye además ventanas donde se puede simular las estrategias clásicas de control, con el fin de compararlas bajo criterios de estabilidad y robustez en diversos modelos de plantas de procesos.

  17. Elección y ensayo del repertorio para la banda escolar o para escolar según grados de dificultad, ejemplificadas con tres obras

    OpenAIRE

    Padilla Restrepo, Luis Felipe

    2015-01-01

    La presente monografía pretende servir de herramienta para directores de bandas musicales que deseen ampliar su experiencia en el estudio de la obra, su ensayo y su proceso en la agrupación musical, de acuerdo con los estándares generales de grados de dificultad -- El trabajo presenta, con una pieza musical por cada nivel, consejos sobre cómo analizar y realizar una correcta selección del repertorio, cómo abordar el ensayo y ejemplos para simular las condiciones que el director encontrará en ...

  18. Ab interno Schlemm's Canal Surgery.

    Science.gov (United States)

    Francis, Brian A; Akil, Handan; Bert, Benjamin B

    2017-01-01

    In primary open-angle glaucoma, the site of greatest resistance to aqueous outflow is thought to be the trabecular meshwork (TM) and inner wall of Schlemm's canal. Augmentation of the conventional (trabecular) outflow pathway can facilitate physiologic outflow and subsequently lower intraocular pressure. The most recent approach to enhancing the conventional outflow pathway is via an internal approach to the TM and Schlemm's canal. Ab interno Schlemm's canal surgery includes 4 novel surgical approaches: (1) removal of the TM and inner wall of Schlemm's canal by an internal approach (ab interno trabeculectomy), (2) implantation of a microstent to bypass the TM, (3) disruption of the TM and inner wall of Schlemm's canal via an internal approach (ab interno trabeculotomy), and (4) dilation of Schlemm's canal via an internal approach (ab interno canaloplasty). The first category includes the Trabectome (Neomedix, Tustin, CA, USA), and Kahook Dual Blade (New World Medical, Rancho Cucamonga, CA, USA). The second category includes the iStent (Glaukos, Laguna Hills, CA, USA), as well as the investigational Hydrus Microstent implant (Ivantis, Irvine, CA, USA). The third category includes gonioscopic-assisted transluminal trabeculotomy (iSciences catheter; Ellex, Adelaide, Australia), and 360° suture trabeculotomy (TRAB360, Sight Sciences, Menlo Park, CA, USA). The fourth category includes ab interno canaloplasty or AbiC (Ellex), and Visco360 (Sight Sciences). In contrast to external filtration surgeries, such as trabeculectomy and aqueous tube shunt, these procedures are categorized as internal filtration surgeries and are performed from an internal approach via gonioscopic guidance. Published results suggest that these surgical procedures are both safe and efficacious for the treatment of open-angle glaucoma. © 2017 S. Karger AG, Basel.

  19. Retention of adhesively bonded posts: effect of pretreatment of the root canal.

    Science.gov (United States)

    Sahafi, Alireza; Peutzfeldt, Anne

    2009-08-01

    To evaluate the effect of three different root canal pretreatments on the retention of prefabricated titanium posts luted in the root canal with one of three resin cements. After removal of the clinical crowns of 216 extracted premolars, the root canals were prepared with the ParaPost system (length = 5 mm, diameter = 1.25 mm). The walls of the roots were subjected to either none (control) or one of three pretreatments: etching with citric acid, application of EDTA C, or mechanical roughening with a diamond-coated bur (n = 18 per group). CoJet-treated ParaPost XH posts were luted in the root canals with one of three resin cements: Panavia 2.0 F, Rely X Unicem, or ParaCem. Following water storage at 37 degrees C for 7 days, retention was determined by extraction of the posts. Mechanical roughening of root canal walls resulted in improved retention of posts, irrespective of the type of resin cement. Etching of root canal walls with citric acid resulted in improved retention only when Panavia 2.0 F was used. Depending on the resin cement, application of EDTA C had either no effect or a negative effect. Luting of posts with Panavia 2.0 F resulted in higher retention than did luting with Rely X Unicem or ParaCem. Mechanical roughening of the root canal walls with a diamond-coated bur was the most effective method to improve retention of posts. The use of Panavia 2.0 F resulted in higher retention than did the use of Rely X Unicem or ParaCem.

  20. Género y dirección frontera en relaciones interorganizativas: estudio exploratorio de su influencia sobre los sistemas de control para la gestión de los canales de exportación independientes

    Directory of Open Access Journals (Sweden)

    Pedro Araújo Pinzón

    2010-01-01

    Full Text Available Esta investigación contribuye al conocimiento sobre los sistemas de control de gestión (SCG en las relaciones inter-organizativas introduciendo la diversidad de género de la persona responsable de la dirección frontera. A través de un análisis cuantitativo exploratorio desarrollado en el contexto de la gestión de los canales de exportación externalizados, se investiga el efecto de las diferencias de género en el nivel de implantación de los diversos tipos de control (de resultados, de comportamiento y social y en el modo de uso (diagnóstico e interactivo de los SCG. Los resultados no evidencian diferencias significativas asociadas al género en cuanto al grado de implantación de los tipos de control ni a la utilidad e importancia conferida a los modos de uso de la información de los SCG. No obstante, los resultados sí indican una cierta preferencia de las mujeres por el uso interactivo, acorde con las habilidades y características socialmente atribuidas a su género.

  1. Developmental spinal canal stenosis and somatotype.

    OpenAIRE

    Nightingale, S.

    1989-01-01

    The hypothesis that somatotype and cervical spine developmental canal stenosis may be associated has been investigated by anthropometry and measurement of lateral projection cervical spine radiographs. A significant association of canal size with somatotype has been found such that those with developmentally narrow canals are more likely to have relatively shorter long-bones, particularly in the upper arm, and longer trunks.

  2. Control electrónico de un banco de ensayos para motores de combustión interna alternativos

    OpenAIRE

    López Groba, Sonia

    2017-01-01

    La realización de ensayos a los motores de combustión interna alternativos es de gran importancia para su desarrollo. Se realizan en bancos de pruebas, para poder simular distintas condiciones de carga. Para estos ensayos, se utiliza un freno dinamométrico unido al eje de salida del motor, que aporta un par resistente y absorbe la potencia. Este elemento es, en esencia, un rotor, acoplado al eje del motor, que proporciona un par resistente inducido por el estator. En el banco de pruebas...

  3. Erie Canal Technology: Stump Pullers

    Science.gov (United States)

    Greenslade, Thomas B., Jr.

    2013-01-01

    Many years ago I saw a picture of a huge set of wheels that was used to remove tree stumps during the construction of the Erie Canal (1817-1825) and was intrigued by its use of leverage, mechanical advantage, and torque. Figure 1 is a scale model of the device based on my memory of the (lost) picture and published accounts.

  4. Contemporary root canal filling strategies

    NARCIS (Netherlands)

    Moinzadeh, A.T.

    2016-01-01

    Currently, clinicians can choose from a wide range of root canal filling materials and techniques, some of which have been evaluated in this thesis. Methacrylate resin-based sealers suffer from polymerization shrinkage stresses. This limitation may partly be overcome by a two-step cementation

  5. Retention of Root Canal Posts

    DEFF Research Database (Denmark)

    Sahafi, A; Benetti, Ana Raquel; Flury, S

    2015-01-01

    ] and a self-etch adhesive resin cement [Panavia F2.0]) were used. After removal of the crowns of 360 extracted premolars, canines, or incisors, the root canals were prepared with a parallel-sided drill system to three different final diameters. Half the posts did not receive any pretreatment. The other half...

  6. Modelado y Simulación Dinámica de Máquinas Sincrónicas de Imanes Permanentes para Aplicaciones Eólicas

    OpenAIRE

    Castillo, Isaac

    2009-01-01

    Recientemente la máquina sincrónica de imanes permanentes ha demostrado ser una tecnología prometedora para aplicaciones eólicas. Esta máquina es similar a la máquina sincrónica clásica excepto que la excitación es provista por imanes permanentes en lugar de un devanado de campo, su modelo matemático es utilizado para crear un modelo computacional en SIMULINK. Con este modelo se simula una máquina para condiciones comunes en aplicaciones eólicas, también puede ser utilizado para simular otr...

  7. Género y dirección frontera en relaciones interorganizativas: estudio exploratorio de su influencia sobre los sistemas de control para la gestión de los canales de exportación independientes.

    Directory of Open Access Journals (Sweden)

    Pedro Araujo Pinzon

    2010-06-01

    Full Text Available Esta investigación contribuye al conocimiento sobre los sistemas de control de gestión (SCG en las relaciones inter-organizativas introduciendo la diversidad de género de la persona responsable de la dirección frontera. A través de un análisis cuantitativo exploratorio desarrollado en el contexto de la gestión de los canales de exportación externalizados, se investiga el efecto de las diferencias de género en el nivel de implantación de los diversos tipos de control (de resultados, de comportamiento y social y en el modo de uso (diagnóstico e interactivo de los SCG. Los resultados no evidencian diferencias significativas asociadas al género en cuanto al grado de implantación de los tipos de control ni a la utilidad e importancia conferida a los modos de uso de la información de los SCG. No obstante, los resultados sí indican una cierta preferencia de las mujeres por el uso interactivo, acorde con las habilidades y características socialmente atribuidas a su género.This research is intended to contribute to knowledge about the role of management control systems (MCS in interorganisational relationships analysing gender diversity of boundary managers. By means of an exploratory quantitative analysis in the setting of externalized export channels, we research the effect of gender differences on implementation level of MCS control types (output, behaviour and social controls and on MCS use mode (diagnostic and interactive uses. Results do not show significant differences related to gender regarding level of implementation of control types, or utility and importance conferred to use modes of MCS information. Notwithstanding, results suggest a slight preference of women for interactive use, according to skills and characteristics socially attributed to this gender.

  8. Mandibular Second Premolar with Four Canals

    Directory of Open Access Journals (Sweden)

    Javad Ghiasi

    2015-09-01

    Full Text Available A mandibular second premolar with four canals is an interesting example of anatomic variations. This report describes a case of a mandibular second premolar with three roots and four canals (one mesiobuccal, two distobuccal and one lingual. The canals were prepared using K-files and irrigated with NaOCl (5.25% and normal saline as the final irrigant. The canals were filled laterally with gutta percha and AH26 sealer (De Trey, Dentsply, Switzerland. This case shows a rare anatomic configuration and points out the importance of looking for additional canals.

  9. Efectividad y eficiencia de los canales de búsqueda de empleo en colombia

    OpenAIRE

    Restrepo Isaza, Lina Maria

    2013-01-01

    El mercado laboral no puede definirse como una institución en la cual confluyen oferentes y demandantespara negociar una mercancía a un precio determinado; se ha identificado que existen distintos mecanismos,que son canales de búsqueda, mediante los cuales los agentes logran emparejar su capacidad de trabajarcon las vacantes disponibles. Para verificar la efectividad y la eficiencia de estos canales de búsquedase utilizó la información de la Gran Encuesta Integrada de Hogares, para las 13 áre...

  10. Programa Nacional de Clasificación de Canales Bovinas en Costa Rica

    OpenAIRE

    Murillo-Bravo, Olger; Galindo-Badilla, Jaime; Unruh, John; Arce-Calderón, Carlos; Blanco-González, Angie; Gadea-Baltodano, Antonio; Martínez-Gutiérrez, Bernal; Rodríguez-Barquero, Ronny

    2012-01-01

    Proyecto de Investigación CÓDIGO: 5402 - 2151- 5101 El presente estudio tuvo como objetivo general evaluar las principales características de las canales de bovinos sacrificados en el país, con el fin de establecer un sistema de clasificación de canales bovinas basadas en la calidad de la carne. Para ello, se seleccionaron animales de las regiones Huetar Norte, Huetar Atlántica y Chorotega de Costa Rica. Para cada una de ellas se tomaron 48 animales, alimentados a base de pasturas y selecc...

  11. El Tercer Canal

    Directory of Open Access Journals (Sweden)

    George McBean

    2015-01-01

    Full Text Available La mayoría de los jóvenes adultos dirán que han aprendido tanto en su tiempo libre como lo que han aprendido en su educación formal. El entorno de la información ha cambiado tan dramáticamente en los últimos veinte años qu elos jóvenes adultos están siendo expuestos a opciones de estilo de vida que nunca fueron parte de la experiencia de sus padres. Por lo tanto, la nueva generación frecuentemente exhibe cualidades y comportamientos con los que los padres no se pueden asociar. Los jóvenes adultos de hoy en día pueden ser talentosos en una variedad de actividades, astutos en la compresnsión y más prestos a desafiar la autoridad. También sienten frustración ante la variedad de opciones que aprentemente tienen a la mano, pero que parecen imposibles de lograr. Sean cuales fueren los retos individuales para la juventud, los educadores nos vemos obligados a buscar las solucionesen toda la gama de las posibilidades en lugar de tratar de encontrarlas en la historia.

  12. Propuesta de rediseño del canal "AOG" para la distribución de repuestos aeronáuticos de la Jefatura de Operaciones Logísticas de la Fuerza Aérea Colombiana

    Directory of Open Access Journals (Sweden)

    Carlos Adrián Castro Barona

    2009-01-01

    Es necesario resaltar la necesidad de adaptar y estandarizar las Polìticas, Objetivos y Misión contemplados en el Plan Estratégico Institucional 2006-2019 de la Fuerza Aérea, orientándolos a mejorar la logística integral de las aeronaves para de esta manera cumplir adecuadamente con la prioridad de nivel uno en el alistamiento de las mismas.

  13. 75 FR 39632 - Regulated Navigation Area; Gulf Intracoastal Waterway, Inner Harbor Navigation Canal, Harvey...

    Science.gov (United States)

    2010-07-12

    ..., Inner Harbor Navigation Canal, Harvey Canal, Algiers Canal, New Orleans, LA; Correction ACTION: Interim... Navigation Canal, Harvey Canal, Algiers Canal, New Orleans, LA into the Code of Federal Regulations. That...

  14. Viagens na minha terra: perfeita adequação entre código e canal para uma boa comunicação = Viagens na minha terra: perfect match between code and medium for a good communication

    OpenAIRE

    Munari, Ana Cláudia; Hohlfeldt, Antônio

    2013-01-01

    O artigo faz uma revisitação ao livro Viagens na minha terra, de Almeida Garrett, mostrando que a escolha de publicá-lo em uma revista semanal está diretamente ligada à opção estilística do autor de produzir um texto que concretizasse, pela imprensa, a sua preocupação didática, enquanto militante político em prol do liberalismo, da democracia e da liberdade em geral, de informar e explicar ao povo, sobretudo aquele menos letrado, os acontecimentos de seu tempo. Inclassificável para muitos, ne...

  15. [Tomography of the pterygoid canals].

    Science.gov (United States)

    Riazantsev, S V; Kalenov, V E; Russkikh, N A

    1990-01-01

    This paper presents an X-ray scheme for calculating the depth of pterygoid canals required for accurate tomography. The scheme includes three lines: line A corresponds to the physiological horizontal line, line B is drawn, normally to line A through the tip of the nose, and line C is the perpendicular from line B to the upper third of the posterior wall of the pterygopalatine fossa. The length of line B plus 1 cm (thickness of external nose soft tissues) is the value to be determined. Twenty-six patients underwent X-ray examinations by an EDK-750B unit (70 kV, 150 mA, 1.65 s). In all cases 1-3 images were sufficient to obtain good visualization of the pterygoid canals.

  16. A STUDY OF ROOT CANAL MORPHOLOGY OF Cebus apella TEETH ESTUDO ANATÔMICO DO CANAL RADICULAR DE DENTES DE Cebus apella

    Directory of Open Access Journals (Sweden)

    Priscilla Rocha Afonso

    2008-12-01

    Full Text Available Realizou-se um estudo anatômico em dentes do Cebus apella, para análise da anatomia interna do canal radicular dessa espécie, normatizando seu uso como modelo experimental. Utilizaram-se doze animais adultos. Após a remoção do tecido orgânico, os dentes foram removidos, seccionados e fotografados, sendo analisados com um estereomicroscópio. Os resultados mostraram que os dentes apresentaram características semelhantes às dos seres humanos, mas com algumas peculiaridades, tais como: a anatomia do canal radicular variou de oval para circular; nos caninos inferiores, os canais são semelhantes a um rim, o que reflete o contorno externo da raiz; nos molares superiores, os canais mesiobucal e distobucal são ovais, seguindo o contorno geral do dente. Os autores concluem que esta espécie pode ser utilizada como modelo em pesquisas odontológicas, principalmente em estudos do tratamento do sistema de canal radicular.

    PALAVRAS-CHAVES: Anatomia, dentes, Cebus apella. An anatomic study of Cebus apella root teeth was performed to analyze the internal anatomy of permanent dentition, normalizing its use as experimental model endodontic research. Twelve adult animals were used in this study. After the removal of the organic tissue, the all teeth were removed, sectioned, analyzed and photographed with a stereomicroscope. The results showed that the anatomy of root canal of this species are similar to human dental anatomy, considering the shape, pathway and number of canals, but with some peculiarities, such as: the root canal anatomy varied from oval to circular; in the lower canines, the canals are resembled a kidney, reflecting the outside contour of the root; in the upper molars, the mesiobuccal and distobuccal canals are oval, following the general contour of the tooth. The authors conclude that this primate can be applied as models for study of root canal treatment in human beings, in special the upper central and lateral incisors

  17. Scalloping at the lumbosacral canal

    Energy Technology Data Exchange (ETDEWEB)

    Reinhardt, R.

    1987-07-01

    Scalloping is an indentation of the dorsal side of the vertebral body (anterior wall of the lumbosacral or sacral canal) which typically involves several adjacent lumbal vertebral body segments and the anterior wall of the canalis sacralis. Occurrence without underlying disease is rare; it occurs most frequently with chondrodystrophy, neurofibromatosis, Morquio's syndrome, Hurler's syndrome, acromegaly, Ehlers-Danlos syndrome, Marfan's syndrome, cysts, tumors and in peridural lipomas.

  18. Endometriosis en el canal inguinal

    OpenAIRE

    Quirós, José Luis; Corrales, Daniela

    2013-01-01

    Resumen: Endometriosis se define como la presencia de tejido glandular y estromal endometrial fuera de la cavidad uterina y este tejido ectópico es dependiente de la estimulación estrogénica. Usualmente se presenta en ovarios, fondos de saco, ligamento ancho, ligamento uterosacro, útero, trompas de Falopio, tracto gastrointestinal y geniturinario. Sin embargo, puede presentarse en otras localizaciones, como en el canal inguinal. Prevalece en 10% de las mujeres en edad reproductiva. Existen mu...

  19. Microbiology of normal external auditory canal.

    Science.gov (United States)

    Stroman, D W; Roland, P S; Dohar, J; Burt, W

    2001-11-01

    To isolate and characterize bacteria and fungi from the healthy ear and to obtain susceptibility profiles on each bacterial isolate. Prospective. Specimens were collected from the external canals and cerumen of healthy subjects. Species-level identification was obtained by combining phenotypic and genotypic data. End-point minimal inhibitory concentration testing was performed using National Committee for Clinical Laboratory Standards recommended methods. One hundred sixty-four subjects were cultured. Seventeen canal and 16 cerumen specimens showed no growth. One hundred forty-eight cerumen specimens yielded 314 organisms, including 23 fungi. One hundred forty-seven canal specimens yielded 310 organisms, including 7 fungi. Of 291 bacteria isolated from cerumen, 99% were Gram-positive. Of 302 bacteria isolated from the canal, 96% were Gram-positive. Staphylococci were 63% of both the cerumen bacteria and the canal bacteria. Coryneforms represented 22% of the bacteria in cerumen and 19% in the canal. Turicellaotitidis was the primary coryneform isolated from both the canal and the cerumen. Streptococci-like bacteria were 10% from the cerumen, 7% from the canal. In both cerumen and canal, Alloiococcusotitis was more than 95% of the streptococci-like bacteria. Fifteen gram-negative organisms were isolated from the canal and cerumen, including four Pseudomonas aeruginosa strains. The percentages of Staphylococcus epidermidis isolates that had high-level resistance (> or =8 microg/mL) were as follows: to neomycin, 28% from cerumen and 11% from the canal; to oxacillin, 28% from cerumen and 25% from the canal; and to ofloxacin, 15% from cerumen and 19% from the canal. Turcellaotitidis and A. otitidis were present with a much higher frequency than previously described, lending evidence that they be considered normal otic flora. Corynebacterium auris, previously reported only in children, was isolated from normal adults.

  20. Control y gestión gerencial en la producción audiovisual para canales de televisión como soporte a la toma de decisiones basado en tecnología web

    OpenAIRE

    Asencio Santos, Reyna; Hidalgo Espinoza, M. Fernanda; Ramírez Granda, Andrea; Galio M, Gustavo

    2011-01-01

    La empresa SOFTRAH S.A. enfocó sus esfuerzos en la realización de E-ProdTV, un Sistema de Gestión para Control de Producciones Audiovisuales. Este es el primer producto que la empresa lanzará al mercado, y con el que espera tener éxito, basado en un servicio que busca la satisfacción del cliente, a través de una herramienta tecnológica, que soporte su infraestructura en la producción audiovisual. La elaboración de una producción, inicia con un libreto desglosado en capítulos y esc...

  1. Duración del desempleo y canales de búsqueda de empleo en Colombia

    Directory of Open Access Journals (Sweden)

    Carlos Augusto Viáfara L.

    2009-12-01

    Full Text Available Este artículo estudia la duración del desempleo en Colombia como indicador de la efectividad de los canales de búsqueda de empleo, con información de la Encuesta Continua de Hogares (ECH del segundo trimestre de 2006. Se estiman modelos de duración paramétricos (Weibull de riesgos proporcionales y no paramétricos (Kaplan-Meier. Los resultados indican que en la duración del desempleo influye considerablemente el canal de búsqueda que usan los empleados para conseguir empleo y los desocupados para buscarlo. Los canales más formales son más efectivos.

  2. Developmental spinal canal stenosis and somatotype.

    Science.gov (United States)

    Nightingale, S

    1989-01-01

    The hypothesis that somatotype and cervical spine developmental canal stenosis may be associated has been investigated by anthropometry and measurement of lateral projection cervical spine radiographs. A significant association of canal size with somatotype has been found such that those with developmentally narrow canals are more likely to have relatively shorter long-bones, particularly in the upper arm, and longer trunks. Images PMID:2769282

  3. Development of the anterior chordal canal.

    Science.gov (United States)

    Tóth, Miklós; Moser, Gerhard; Patonay, Lajos; Oláh, Imre

    2006-01-01

    Resent advances have led to the reexamination of the intraosseous pathway of the chorda tympani a few years ago and they stated that the nerve never enters the mandibular fossa and its exit the skull base in the sphenopetrosal fissure. In our report, 58 temporal bones were investigated after maceration and formalin fixation in order to understand the development of the anterior chordal canal. Our study revealed that the chorda tympani leaves the tympanic cavity through the tympanosquamosal fissure before formation of the anterior chordal canal of Huguier. This canal is situated parallel to and in front of the musculotubal canal and formed by the processus inferior tegminis tympani and the sphenoid bone between the second and fifth years of age. Prior to the age of 2, only the exit of the bony canal exists which is gradually followed by the appearance of a groove in the growing processus inferior tegminis tympani. The borders of the groove elevate and develop to upper and lower plates which lengthen with similar plates of the sphenoid bone, completing the anterior chordal canal by the fifth postnatal year. The entrance of the canal develops above the petrotympanic fissure and similar to the canal itself, it is also completely formed in the fifth year. In case of an incomplete development the anterior chordal canal remains partially opened laterally which might allow the head of the mandibula to effect the chorda tympani mechanically causing Costen's syndrome.

  4. Asociación determinístico-estocástica para predicción de caudales

    OpenAIRE

    Chavasse, Diana Irene; Seoane, Rafael Santiago

    1997-01-01

    En este trabajo se propone una metodología que aplica un modelo detenninístico complejo, compuesto por uno de traslado y otro de humedad de suelo, y un modelo estocástico para simular los procesos de transformación precipitación-caudal y de propagación de crecidas en una cuenca de gran extensión. Por otra parte se realiza un experimento para analizar la capacidad de pronóstico del modelo deteminístico complejo. En la primera parte se verifica la calibración de este modelo deteminístico y s...

  5. Diseño de un sistema de biofiltración para la remoción de estireno

    OpenAIRE

    Jimenez-Roldan, E. (Esteban); Villegas, A. M. (Ana María)

    2004-01-01

    El presente trabajo se enfocó en desarrollar un proceso para la eliminación del gas estireno, un contaminante orgánico generador de malos olores en el aire. Se construyó un sistema de biofiltración en el cual se emplearon bacterias del tipo Pseudomona aeruginosa y Escherichia coli adheridas a un soporte de piedra pómez. Se contaminó aire con estireno en concentraciones por encima del estándar norteamericano (TLV 40 ppm, ACGIH 2002), para simular una atmósfera laboral de alto riesg...

  6. Dietas con follaje de yuca y su efecto sobre las caracteristicas al sacrificio y rendimiento en canal y en cortes de pollos de engorde

    National Research Council Canada - National Science Library

    Trompiz, Jacqueline; Villamide, Maria Jesus; Ferrer, Alexis; Arenas, Lilia; Jerez, Nancy; Sandoval, Luis

    2010-01-01

    ...%) en raciones alimenticias para pollos de engorde sobre las caracteristicas al sacrificio y el rendimiento en canal y en cortes, se usaron 32 pollos de engorde, hembras de la raza Cobb de 42 dias de edad...

  7. Root canal treatment of mandibular second premolar with four root canals

    Directory of Open Access Journals (Sweden)

    Bander Al-Abdulwahhab

    2015-01-01

    Full Text Available Variation in the morphology of the root canal system of mandibular premolars has been demonstrated. This diverse morphology challenges for the clinician to clean, shape, and fill the entire root canal system. A case report of a mandibular second premolar with four root canals separated at the apical third and underwent endodontic treatment is presented.

  8. 5 CFR 315.601 - Appointment of former employees of the Canal Zone Merit System or Panama Canal Employment System.

    Science.gov (United States)

    2010-01-01

    ... Canal Zone Merit System or Panama Canal Employment System. 315.601 Section 315.601 Administrative... employees of the Canal Zone Merit System or Panama Canal Employment System. (a) Agency authority. This... Zone Merit System, which was in effect before March 31, 1982, or under the Panama Canal Employment...

  9. Seguimento dos doentes soropositivos e soronegativos para o HIV com carcinoma espinocelular do canal anal Follow-up for HIV negative and HIV-positive patients with anal squamous cells carcinoma

    Directory of Open Access Journals (Sweden)

    Sidney Roberto Nadal

    2009-09-01

    Full Text Available A incidência do carcinoma espinocelular (CEC anal e das neoplasias intra-epiteliais anais (NIA é maior nos pacientes infectados pelo papilomavírus humano (HPV, e está relacionada à imunidade e à infecção pelo vírus da imunodeficiência humana (HIV. A associação com viroses de transmissão sexual indica que seja tumor sexualmente transmitido. A infecção pelo HIV mudou o perfil dos portadores do CEC anal. A doença que anteriormente acometia mulheres na 6ª década de vida, hoje atinge preferencialmente homens na 3ª e 4ª décadas. Nos Estados Unidos, a expectativa de diagnóstico desse tumor aumentou de 19/100.000, na época pré-HAART (1992-1995, para 48,3/100.000 no período pós-HAART imediato (1996-1999 e para 78,2/100.000 pessoas por ano, nos anos mais recentes (2000-2003. O tratamento do CEC anal, descrito por Nigro em 1974, combina radio e quimioterapia. Operações de resgate estão indicadas caso haja persistência ou recidiva da doença. Estudos comparando, respectivamente, doentes imunodeprimidos e imunocompetentes vêm mostrado envolvimento linfonodal em 60% e 17%, recidivas em 75% e 6%, boa resposta à radio e quimioterapia em 62% e 85%, toxicidade a esse tratamento em 80% e 30%, e sobrevivência global de 1,4 e 5,3 anos. A contagem sérica baixa de linfócitos T CD4 prediz mau prognóstico. Quando acima de 200/mm³, os resultados são comparáveis aos observados entre os imunocompetentes.Anal squamous cell carcinoma (ASCC and anal intra-epithelial neoplasia (AIN incidences are bigger among human papillomavirus (HPV infections, and are associated to immunity and to HIV infection. These viruses with sexual transmission in association suggested ASCC is a sexually transmitted tumor. HIV infection changed ASCC patient profile. This kind of tumor committed women in theirs sixties, but nowadays, affects mainly men in the third and forth decades of life. In the United States of America, ASCC was diagnosed in 19/100.000, in the

  10. [Upper lateral incisor with 2 canals].

    Science.gov (United States)

    Fabra Campos, H

    1991-01-01

    Clinical case summary of the patient with an upper lateral incisor with two root canals. The suspicion that there might be an anatomic anomaly in the root that includes a complex root canal system was made when an advanced radicular groove was detected in the lingual surface or an excessively enlarged cingulum.

  11. 33 CFR 117.438 - Company Canal.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Company Canal. 117.438 Section 117.438 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Louisiana § 117.438 Company Canal. (a) The draw of the...

  12. The enigma of the lateral canal.

    Science.gov (United States)

    Weine, F S

    1984-10-01

    It is difficult to summarize an article of this type, in which the author is certain that his case has been presented fairly, but is aware that other views that are contrary could be stated and endorsed by pertinent clinical cases. Bearing this fact in mind, I wish to reiterate the following: Lateral canals are demonstrated in endodontic cases with much less frequency than they exist. This variance rarely, if ever, causes an endodontic failure. Some demonstrated lateral canals may really be other conditions. Preoperative evaluation should include examination of radiographs for lateral, as well as periapical, lesions. Lateral canals may be demonstrated by a variety of filling techniques. Careful canal preparation may enhance the frequency of such demonstration. Cases with necrotic pulps probably yield more frequent demonstration than do cases with vital pulps. Lateral canals harboring inflamed and/or infected material may cause pain during endodontic treatment. They may simulate periodontal disease and may cause problems with treatment if present when a tooth is left open for drainage. Periodontal disease may cause pulp exposure via lateral canals located coronally. Improper use of post room may lead to lateral failure from breakdown of tissue in a lateral canal. The enigma of the lateral canal has been the object of description and discussion in many articles, but no one is truly certain of their exact significance in endodontic therapy for the long haul.

  13. Computed Tomography Findings of Mandibular Nutrient Canals.

    Science.gov (United States)

    Kawashima, Yusuke; Sekiya, Kotaro; Sasaki, Yusuke; Tsukioka, Tsuneyuki; Muramatsu, Teruaki; Kaneda, Takashi

    2015-08-01

    The purpose of this study was to assess computed tomography (CT) findings of mandibular nutrient canals using CT images. We retrospectively analyzed the mandibular CT images of 194 consecutive patients. For image analysis such as canal prevalence, location, number, size, shape, and the CT value of nutrient foramina were determined using CT axial images of 0.5 and 3 mm slice thickness. We revealed that the nutrient canals were seen 94.3% in the mandible, mostly seen in the anterior region. By location, nutrient canals were particularly seen between the central and lateral incisors. The mean number of nutrient canals was 2.7. The mean diameter of the nutrient foramen between the central and lateral incisors was 1.0 mm. In about 80% of the cases, foramina between the central and lateral incisors were ovoid. The mean CT value for the nutrient foramina between the central and lateral incisors was 411 HU. Mandibular nutrient canals were ovoid shape, and the mean CT value was 411 HU. By preoperative knowledge of the position and anatomy of the mandibular nutrient canals, complications such as injury to the nutrient canals can be avoided.

  14. Fracturas de implantes de tibia. Consecuencias para los ensayos de los implantes

    OpenAIRE

    Frei, S.; Ploeg, H.; Reinschmidt, C.; Heuberger, P.

    1999-01-01

    El objetivo de este trabajo es estudiar los modelos de fracturas de prótesis de tibia descritos en la literatura y, sobre la base de dichos conocimientos, desarrollar un ensayo para implantes en la cual se logren simular condiciones fisiológicas. El caso descrito con mayor frecuencia en la literatura es la migración de la parte medial de la prótesis, fenómeno que, a menudo, antecede a la fractura de la prótesis. La posición defectuosa resultante de dicha migración modifica el eje ...

  15. Type III apical transportation of root canal

    Directory of Open Access Journals (Sweden)

    Shiv P Mantri

    2012-01-01

    Full Text Available Procedural accidents leading to complications such as canal transportation have been ascribed to inapt cleaning and shaping concepts. Canal transportation is an undesirable deviation from the natural canal path. Herewith a case of apical transportation of root canal resulting in endodontic retreatment failure and its management is presented. A healthy 21-year-old young male presented discomfort and swelling associated with painful endodontically retreated maxillary incisor. Radiograph revealed periradicular radiolucency involving underfilled 11 and overfilled 12. Insufficiently obturated 11 exhibited apical transportation of canal. This type III transportation was treated by periradicular surgery and repair using white mineral trioxide aggregate (MTA. Comfortable asymptomatic patient presented uneventful healing at third and fourth month recall visits. A decrease in the size of radiolucency in radiograph supported the clinical finding. In the present case, MTA is useful in repairing the transportation defect. The result of these procedures is predictable and successful.

  16. Updated regime equations for alluvial Egyptian canals

    Directory of Open Access Journals (Sweden)

    Fahmy Salah Abdelhaleem

    2016-03-01

    Full Text Available Real accuracy of several regime relationships for designing stable alluvial channels in Egypt was determined. Extensive field measurements had been carried out on 26 Egyptian stable canals, which cover various categories of irrigation canals starting from distributary, branch to carrier canals in Egypt. Analysis of 1484 velocity profiles for 371 cross sections was employed in order to formulate new regime equations characterizing Egyptian canals. The functional formulations to include the flow depth, cross section area, hydraulic radius and mean velocity were achieved. This research compared the deduced formulas from the measured data with the equations derived by other researchers for stable channel design. It was found that the derived formulas are reliable and could help in the design of Egyptian canals to convey a discharge ranging from 0.11 to 287.5 m3/s (0.0095–24.84 millions m3/day.

  17. Duración del desempleo y canales de búsqueda de empleo en Colombia

    OpenAIRE

    Carlos Augusto Viáfara L; José Ignacio Uribe G.

    2009-01-01

    Este artículo estudia la duración del desempleo en Colombia como indicador de la efectividad de los canales de búsqueda de empleo, con información de la Encuesta Continua de Hogares (ECH) del segundo trimestre de 2006. Se estiman modelos de duración paramétricos (Weibull de riesgos proporcionales) y no paramétricos (Kaplan-Meier). Los resultados indican que en la duración del desempleo influye considerablemente el canal de búsqueda que usan los empleados para conseguir empleo y los desocupado...

  18. Looking back at Love Canal

    Energy Technology Data Exchange (ETDEWEB)

    Deegan, J. Jr.

    1987-04-01

    The comprehensive environmental study which describes the results of a monitoring program conducted by EPA at Love Canal is evaluated by EPA's former study director. Attention is focused on the episode's history and the agency's study methods. The aim of the program was to constitute a study team, design a monitoring study, reprogram and reallocate the financial resources needed to conduct the study, and identify and employ contractors who would collect and analyze environmental samples. The agency was directed to ensure the quality of the data acquired from various environmental media and analyzed by numerous laboratories; to integrate, interpret, and report the data; and to assess, from an environmental perspective, the habitability of the area.

  19. MODELADO DE CANAL INALÁMBRICO OFDM, HACIA LAS COMUNICACIONES 4G

    Directory of Open Access Journals (Sweden)

    Miguel Angel Del Valle Diego

    2009-01-01

    Full Text Available La creciente aplicación de las comunicaciones inalámbrica, requiere del constante desarrollo de técnicas de transmisión, protocolos y tecnología que permitan mayor capacidad de servicios de comunicación en medios de transmisión hostil y de asignación de espectro limitadas, tal como lo es el canal por donde se envían las señales de comunicación inalámbrica. El conocimiento de las características de propagación en el canal es clave para el diseño y desarrollo de los sistemas de transmisión, por lo que las mediciones del canal y su caracterización son fundamentales para desarrollar modelos que lo describan adecuadamente y que permitan, tanto simulación, como para establecer varios escenarios de aplicación y evaluar los desarrollos antes mencionados. En este artículo, se enfatiza el modelado de canal inalámbrico a una propagación sin línea de vista (en inglés NLOS en un entorno externo con multitrayecto, encaminado a las comunicaciones 4G y en donde, para mitigar la distorsión y degradación de la señal recibida, se utilizan diversas técnicas que atacan primero la distorsión y luego el desvanecimiento. Lo primero se puede combatir, por ejemplo, con ecualización, espectro ensanchado, OFDM, transmisión de señal piloto, modulaciones robustas, codificación y entrelazado, etc. Lo segundo, con codificación de canal y diversidad de envío de señales (espacial, frecuencial, temporal, de polarización, etc.

  20. Wave Mechanics of the Vestibular Semicircular Canals.

    Science.gov (United States)

    Iversen, Marta M; Rabbitt, Richard D

    2017-09-05

    The semicircular canals are biomechanical sensors responsible for detecting and encoding angular motion of the head in 3D space. Canal afferent neurons provide essential inputs to neural circuits responsible for representation of self-position/orientation in space, and to compensatory circuits including the vestibulo-ocular and vestibulo-collic reflex arcs. In this work we derive, to our knowledge, a new 1D mathematical model quantifying canal biomechanics based on the morphology, dynamics of the inner ear fluids, and membranous labyrinth deformability. The model takes the form of a dispersive wave equation and predicts canal responses to angular motion, sound, and mechanical stimulation. Numerical simulations were carried out for the morphology of the human lateral canal using known physical properties of the endolymph and perilymph in three diverse conditions: surgical plugging, rotation, and mechanical indentation. The model reproduces frequency-dependent attenuation and phase shift in cases of canal plugging. During rotation, duct deformability extends the frequency bandwidth and enhances the high frequency gain. Mechanical indentation of the membranous duct at high frequencies evokes traveling waves that move away from the location of indentation and at low frequencies compels endolymph displacement along the canal. These results demonstrate the importance of the conformal perilymph-filled bony labyrinth to pressure changes and to high frequency sound and vibration. Published by Elsevier Inc.

  1. How to bond to root canal dentin

    Science.gov (United States)

    Nica, Luminita; Todea, Carmen; Furtos, Gabriel; Baldea, Bogdan

    2014-01-01

    Bonding to root canal dentin may be difficult due to various factors: the structural characteristic of the root canal dentin, which is different from that of the coronal dentin; the presence of the organic tissue of the dental pulp inside the root canal, which has to be removed during the cleaning-shaping of the root canal system; the smear-layer resulted after mechanical instrumentation, which may interfere with the adhesion of the filling materials; the type of the irrigants used in the cleaning protocol; the type of the sealer and core material used in the obturation of the endodontic space; the type of the materials used for the restoration of the endodontically treated teeth. The influence of the cleaning protocol, of the root canal filling material, of the type of the adhesive system used in the restoration of the treated teeth and of the region of the root canal, on the adhesion of several filling and restorative materials to root canal dentin was evaluated in the push-out bond strength test on 1-mm thick slices of endodontically treated human teeth. The results showed that all these factors have a statistically significant influence on the push-out bond strength. Formation of resin tags between radicular dentin and the investigated materials was observed in some of the samples at SEM analysis.

  2. Panama Canal Watershed Experiment- Agua Salud Project

    Science.gov (United States)

    Stallard, Robert F.; Ogden, Fred L.; Elsenbeer, Helmut; Hall, Jefferson S.

    2010-01-01

    The Agua Salud Project utilizes the Panama Canal’s (Canal) central role in world commerce to focus global attention on the ecosystem services provided by tropical forests. The Canal was one of the great engineering projects in the world. Completed in 1914, after almost a decade of concerted effort, its 80 km length greatly shortened the voyage between the Atlantic and Pacific Oceans. An entire class of ships, the Panamax, has been constructed to maximize the amount of cargo that can be carried in a Canal passage. In today’s parlance, the Canal is a “green” operation, powered largely by water (Table 1). The locks, three pairs on each end with a net lift of 27 meters, are gravity fed. For each ton of cargo that is transferred from ocean to ocean, about 13 tons of water (m3) are used. Lake Gatún forms much of the waterway in the Canal transect. Hydroelectricity is generated at the Gatún dam, whenever there is surplus water, and at Madden Dam (completed in 1936) when water is transferred from Lake Alhajuela to Lake Gatún. The Canal watershed is the source of drinking water for Panama City and Colon City, at either end of the Canal, and numerous towns in between.

  3. Canal lombar estreito: sinal da sedimentação

    Directory of Open Access Journals (Sweden)

    Vera Alice Correia Resende

    2013-01-01

    Full Text Available OBJETIVO: Verificar a presença do sinal de sedimentação nos pacientes com canal lombar estreito (CLE comparando-os com os pacientes sem CLE. MÉTODOS: Realizado um estudo retrospectivo, transversal e descritivo. Realizada a revisão dos processos imagiológicos dos pacientes com CLE operados entre 1 de janeiro de 2008 e 31 de dezembro de 2009, comparando-os com os dos pacientes sem CLE observados em consulta externa. Os pacientes foram divididos em dois grupos: grupo I com 34 pacientes com diagnóstico de CLE. Critérios diagnósticos: existência de lombalgia e/ou claudicação neurogénica e/ou radiculopatia, associados a um diâmetro anteroposterior do canal menor que 10mm e grupo II com 40 pacientes observados em consulta externa por lombalgia sem clínica de CLE. Foi feita a medicação do diâmetro do canal e verificada a presença do sinal de sedimentação entre D12 a S1. RESULTADOS: O sinal da sedimentação foi positivo em 31 dos 34 pacientes do grupo I (91,2%, em dois destes 31 pacientes apenas abaixo da estenose. Este sinal não foi encontrado em nenhum paciente do segundo grupo. Verifica-se uma correlação estatisticamente significativa entre as variáveis "diâmetro do canal" e a "presença do sinal da sedimentação" (p<0.01 no grupo de pacientes com canal lombar estreito. CONCLUSÕES: O diagnóstico de CLE nem sempre é fácil atendendo à frequente dissonância entre os achados clínicos e imagiológicos. O sinal de sedimentação é positivo em pacientes com CLE entre os níveis L1 e L5, podendo ser um sinal válido para complementar o diagnóstico de CLE.

  4. Análisis microbiológico de canales de pollo en los mataderos del estado de Zulia, Venezuela

    OpenAIRE

    Molero Saras, Gladys L.

    2012-01-01

    En este trabajo se ha realizado un estudio para evaluar la calidad y seguridad microbiológica de canales de pollo envasadas en cinco mataderos de pollos ubicados en los municipios San Francisco, Maracaibo y Mara, del estado de Zulia, Venezuela (plantas A, B, C, D y E). Para ello se han tomado un total de 30 muestras de canales de pollo envasado entre los cinco mataderos. Asimismo, se han tomado muestras en tres áreas del procesado: evisceración, pre-enfriamiento y enfriamien...

  5. Mandibular Canal Enlargement: Clinical and Radiological Characteristics

    Directory of Open Access Journals (Sweden)

    Chong Jun Ai

    2017-01-01

    Full Text Available Enlargement of the mandibular canal is a rare radiological finding. Clinically, it may or may not be associated with sensory deficits. We report four cases of widening of the mandibular canal observed with various methods of imaging with different clinical characteristics. We describe this unique radiological finding and elaborate the importance of quality assessment of the imaging that is vital for accurate diagnosis and treatment planning. Clinicians should be mindful when assessing the imaging whenever the size of the mandibular canal is implicated. The case ranged from a benign tumor to malignancy, radiological errors, and artifacts. A more superior imaging or treatment modality was necessary to ascertain the diagnosis.

  6. Scanning electron microscopy investigation of canal cleaning after canal preparation with nickel titanium files

    Directory of Open Access Journals (Sweden)

    Živković Slavoljub

    2010-01-01

    Full Text Available Introduction. Root canal preparation is the most important phase of endodontic procedure and it consists of adequate canal space cleaning and shaping. In recent years, rotary instruments and techniques have gained importance because of the great efficacy, speed and safety of the preparation procedure. Objective. The aim of this research was to investigate the influence of different NiTi files on the canal wall cleaning quality, residual dentine debris and smear layer. Methods. The research was conducted on extracted human teeth in vitro conditions. Teeth were divided in 7 main groups depending on the kind of instruments used for root canal preparation: ProTaper, GT, ProFile, K-3, FlexMaster, hand ProTaper and hand GT. Root canal preparation was accomplished by crown-down technique. Prepared samples were assessed on scanning electron microscopy JEOL, JSM-6460 LV. The evaluation of dentine debris was done with 500x magnification, and the evaluation of smear layer with 1,000 times magnification. Quantitive assessment of dentine debris and smear layer was done according to the criteria of Hulsmann. Results. The least amount of debris and smear layer has been found in canals shaped with ProFile instruments, and the largest amount in canals shaped with FlexMaster instruments. Canal cleaning efficacy of hand GT and ProTaper files has been similar to cleaning efficacy of rotary NiTi files. Statistic analysis has shown a significant difference in amount of dentine debris and smear layer on the canal walls between sample groups shaped with different instruments. Conclusion. Completely clean canals have not been found in any tested group of instruments. The largest amount of debris and smear layer has been found in the apical third of all canals. The design and the type of endodontic instruments influence the efficacy of the canal cleaning.

  7. Incidence of accessory canals in Japanese anterior maxillary teeth following root canal filling ex vivo.

    Science.gov (United States)

    Adorno, C G; Yoshioka, T; Suda, H

    2010-05-01

    To investigate the vertical and horizontal distribution and the incidence of accessory canals in Japanese maxillary anterior teeth following root filling. The study included maxillary teeth; 69 central incisors, 61 lateral incisors and 31 canines. After the canal systems had been dyed and root canal instrumentation had been carried out, all prepared canals were filled with gutta-percha without using sealer. Transparent specimens were then obtained and examined with a digital microscope for horizontal and vertical distributions of accessory canals. The incidence of teeth with accessory canals in the apical 3 mm was 46%, 29% and 38% for the maxillary central incisors, lateral incisors and canines, respectively. The horizontal distribution was mainly buccal for central incisors, palatal for lateral incisors and distal and palatal for canines. There was a significant difference (P < 0.05) between the apical 3 mm and the rest of the root (16%, 20% and 19% for the maxillary central incisors, lateral incisors and canines, respectively) in terms of the presence of accessory canals. A high percentage of accessory canals can be found in apical 3 mm of the root. The horizontal distribution of accessory canals differed amongst the tooth types studied.

  8. Canal and isthmus debridement efficacy using a sonic irrigation technique in a closed-canal system.

    Science.gov (United States)

    Johnson, Meenal; Sidow, Stephanie J; Looney, Stephen W; Lindsey, Kimberly; Niu, Li-na; Tay, Franklin R

    2012-09-01

    This in vitro study compared debridement efficacies of a sonic irrigation technique (Vibringe; Cavex Holland BV, Haarlem, The Netherlands) with side-vented needle irrigation (SNI) in the mesiobuccal root of maxillary first molars. Twenty roots with narrow isthmuses (≤ 1/4 canal diameter) were selected using micro-computed tomography scanning. Collagen solution was injected into canals/isthmuses and reconstituted with NH(4)OH to simulate canal debris. Each root was sealed apically and embedded in polyvinyl siloxane simulating a closed-canal system. Canals were instrumented to size 40/.04 taper 1 mm short of the anatomic apex. The final irrigation was performed with the Vibringe or SNI. Roots were demineralized, sectioned at 6 levels (1.2-3.2 mm) from the anatomic apex, and stained using Masson trichrome stain. The areas occupied by canals and isthmus and the debris-containing areas were statistically analyzed with repeated-measures analyses using "irrigation technique" as the between factor and "canal level" as the within factor (α = 0.05). Canals had significantly more debris at 1.2 and 1.6 mm (P .05). Considerably more debris remained at 1.2 and 2.0 mm for the Vibringe (P < .05). A significant difference was observed between the canal and the isthmus (P < .001). There is no difference between the Vibringe and SNI in their overall debridement efficacy in apical one third of the mesiobuccal root of maxillary first molars. Published by Elsevier Inc.

  9. Semicircular canal modeling in human perception.

    Science.gov (United States)

    Asadi, Houshyar; Mohamed, Shady; Lim, Chee Peng; Nahavandi, Saeid; Nalivaiko, Eugene

    2017-07-26

    The human vestibular system is a sensory and equilibrium system that manages and controls the human sense of balance and movement. It is the main sensor humans use to perceive rotational and linear motions. Determining an accurate mathematical model of the human vestibular system is significant for research pertaining to motion perception, as the quality and effectiveness of the motion cueing algorithm (MCA) directly depends on the mathematical model used in its design. This paper describes the history and analyses the development process of mathematical semicircular canal models. The aim of this review is to determine the most consistent and reliable mathematical semicircular canal models that agree with experimental results and theoretical analyses, and offer reliable approximations for the semicircular canal functions based on the existing studies. Selecting and formulating accurate mathematical models of semicircular canals are essential for implementation into the MCA and for ensuring effective human motion perception modeling.

  10. Avaliação do desempenho de canal gramado na remoção de material suspenso em escoamento superficial pluvial

    Directory of Open Access Journals (Sweden)

    Rodrigo Braga Moruzzi

    Full Text Available RESUMO Neste trabalho, buscou-se avaliar o desempenho de canal gramado na remoção de material suspenso presente em escoamento superficial em unidade construída em escala real. Para tal, foram investigadas diferentes concentrações iniciais de material particulado, o qual foi descarregado por meio de chuvas simuladas em canal de 100 m de extensão e declividade de 2%. As medidas de material particulado foram feitas mediante a análise de sólidos suspensos totais (SST em diferentes posições ao longo do canal. Os hidrogramas de descarregamento e as lâminas de água no canal foram monitorados durante a passagem da onda de cheia. Avaliaram-se as frações removidas para cada evento isolado e também em conjunto, por intermédio da interpolação por krigagem. Remoções da ordem de 50% foram obtidas para a posição de 50 m do canal gramado e de 70% para a posição de 80 m. Os resultados mostraram que a remoção de material particulado é fortemente dependente da extensão do canal e que os aspectos dinâmicos decorrentes da passagem da onda de cheia influenciam no processo.

  11. Desarrollo de un sistema de imagen para la planificación de operaciones de la aorta

    OpenAIRE

    Martínez Mera, Juan Antonio

    2014-01-01

    El desarrollo de tecnologías de imagen y más específicamente aquellas relacionadas con la imagen 3D han llevado al desarrollo de nuevos enfoques para las intervenciones en general y en el campo de la cirugía vascular en particular. La posibilidad de obtener modelos de imágenes 3D sobre los cuales simular la intervención, abre la puerta al desarrollo de técnicas de planificación que, desarrolladas sobre modelos 3D virtuales, posibilitan el análisis de riesgos ante diferentes ...

  12. The fluid mechanics of root canal irrigation.

    Science.gov (United States)

    Gulabivala, K; Ng, Y-L; Gilbertson, M; Eames, I

    2010-12-01

    Root canal treatment is a common dental operation aimed at removing the contents of the geometrically complex canal chambers within teeth; its purpose is to remove diseased or infected tissue. The complex chamber is first enlarged and shaped by instruments to a size sufficient to deliver antibacterial fluids. These irrigants help to dissolve dying tissue, disinfect the canal walls and space and flush out debris. The effectiveness of the procedure is limited by access to the canal terminus. Endodontic research is focused on finding the instruments and clinical procedures that might improve success rates by more effectively reaching the apical anatomy. The individual factors affecting treatment outcome have not been unequivocally deciphered, partly because of the difficulty in isolating them and in making the link between simplified, general experimental models and the complex biological objects that are teeth. Explicitly considering the physical processes within the root canal can contribute to the resolution of these problems. The central problem is one of fluid motion in a confined geometry, which makes the dispersion and mixing of irrigant more difficult because of the absence of turbulence over much of the canal volume. The effects of treatments can be understood through the use of scale models, mathematical modelling and numerical computations. A particular concern in treatment is that caustic irrigant may penetrate beyond the root canal, causing chemical damage to the jawbone. In fact, a stagnation plane exists beyond the needle tip, which the irrigant cannot penetrate. The goal is therefore to shift the stagnation plane apically to be coincident with the canal terminus without extending beyond it. Needle design may solve some of the problems but the best design for irrigant penetration conflicts with that for optimal removal of the bacterial biofilm from the canal wall. Both irrigant penetration and biofilm removal may be improved through canal fluid

  13. Estudo de fase II de substituição do 5-FU por capecitabina no esquema de quimio-radioterapia em pacientes com carcinoma de células escamosas do canal anal

    OpenAIRE

    Suilane Coelho Ribeiro Oliveira

    2015-01-01

    Introdução: O carcinoma de células escamosas (CEC) do canal anal é uma neoplasia pouco frequente, correspondendo a 1-5% dos tumores intestinais. Entretanto, o risco de CEC do canal anal vem crescendo. O tratamento padrão do CEC de canal anal nos estádios II-III consiste em 5-fluorouracil infusional associado a mitomicina-C e radioterapia, desde 1974. Estudos clínicos com o objetivo de identificar novos esquemas terapêuticos mais convenientes para câncer do canal anal devem continuar. Métodos:...

  14. Posterior semicircular canal dehiscence: a morphologic cause of vertigo similar to superior semicircular canal dehiscence

    Energy Technology Data Exchange (ETDEWEB)

    Krombach, G.A.; Schmitz-Rode, T.; Haage, P.; Guenther, R.W. [Department of Diagnostic Radiology, University of Technology, Pauwelstrasse 30, 52057, Aachen (Germany); DiMartino, E. [Department of Otorhinolaryngology, University of Technology, Pauwelstrasse 30, 52057, Aachen (Germany); Prescher, A. [Department of Anatomy, University of Technology, Pauwelstrasse 30, 52057, Aachen (Germany); Kinzel, S. [Department of Experimental Veterinarian Medicine, University of Technology, Pauwelstrasse 30, 52057, Aachen (Germany)

    2003-06-01

    Heading Abstract.The aim of this study was to assess imaging findings of posterior semicircular dehiscence on computed tomography and to evaluate incidence of posterior and superior semicircular canal dehiscence in patients presenting with vertigo, sensorineuronal hearing loss or in a control group without symptoms related to the inner ear. Computed tomography was performed in 507 patients presenting either with vertigo (n=128; 23 of these patients suffered also from sensorineuronal hearing loss), other symptoms related to the inner ear, such as hearing loss or tinnitus (n=183) or symptoms unrelated to the labyrinth (n=196). All images were reviewed for presence of dehiscence of the bone, overlying the semicircular canals. Twenty-nine patients had superior semicircular canal dehiscence. Of these patients, 83% presented with vertigo, 10% with hearing loss or tinnitus and the remaining 7% with symptoms unrelated to the inner ear. In 23 patients dehiscence of the posterior semicircular canal was encountered. Of these patients, 86% presented with vertigo, 9% with hearing loss or tinnitus and 5% with symptoms unrelated to the inner ear. Defects of the bony overly are found at the posterior semicircular canal, in addition to the recently introduced superior canal dehiscence syndrome. Significant prevalence of vertigo in these patients suggests that posterior semicircular canal dehiscence can cause vertigo, similar to superior semicircular canal dehiscence. (orig.)

  15. Medida da área do canal vertebral lombar em diferentes faixas etárias Medida de la superficie del canal vertebral lumbar en los diferentes grupos de edad Lumbar spinal canal area in different age groups

    Directory of Open Access Journals (Sweden)

    Jair Ortiz

    2009-03-01

    Full Text Available OBJETIVO: medir as dimensões do canal vertebral lombar por meio de tomografia computadorizada, de modo a comparar os valores das diferentes faixas etárias e determinação da possível diferença entre elas. MÉTODOS: a área do canal vertebral lombar foi medida em 78 indivíduos, divididos em oito grupos etários, com dados obtidos de exames de tomografia computadorizada do abdômen. As medidas foram realizadas nos cortes axiais nas vértebras L1, L3 e L5 ao nível da região trans-pedicular. Utilizado o método estatístico de ANOVA (análise de variância com análise de diferentes "p-value" para cada grupo estudado. RESULTADOS: as medidas para L1 produziram um "p-value" de 0,586 para a faixa etária e um "p-value" de 0,003 para o sexo. Portanto, não há diferença entre as faixas etárias e há diferença entre os sexos, sendo maior no sexo masculino. Para L3, o "p-value" da faixa etária foi de 0,258 e para o sexo de 0,062; no caso de L5, o "p-value" para a faixa etária foi de 0,279 e para o sexo de 0,003. CONCLUSÃO: não foi observada diferença estatística da área do canal vertebral lombar nos níveis L1, L3 e L5 nas diferentes faixas etárias. No entanto o diâmetro no sexo masculino foi maior com diferença estatística.OBJETIVO: medir el área del canal vertebral lumbar, utilizando la tomografía computarizada, comparándolo entre los distintos grupos de edad y determinar si existen diferencias entre ellos. MÉTODOS: el área del canal vertebral lumbar se midió en 78 temas, divididos en 8 grupos, con los datos obtenidos a partir de exploraciones de tomografía computarizada del a domen. Las mediciones se hicieron en las vértebras L1, L3 y L5 en la región transpedicular. RESULTADOS: medidas para L1 producido un p-valor de 0,586 para el grupo de edad y un p-valor de 0,003 para el sexo, por tanto, no hay diferencia entre los grupos de edad y hay diferencias entre los sexos, siendo mayor en los hombres; para L3, el "pvalue" del

  16. Canal de Menorca. Áreas de estudio del proyecto LIFE+ INDEMARES

    OpenAIRE

    Barberá, C.; Arcos, J. M.; Druet-Vélez, M. (María); Grinyó, J; Requena, S.; Gili, J. M.; S. MALLOL; Balbín, R. (Rosa); Campillos, M

    2014-01-01

    Se integra información hidrográfica, geomorfológica, sedimentológica, biológica y pesquera, para establecer la bases ecológicas necesarias para la protección y conservación del canal de Menorca El área del “Canal de Menorca” es un corredor marino situado entre las islas de Mallorca y Menorca, del archipiélago de las islas Baleares, que presenta una amplitud mínima entre islas de 36 kilómetros. En sus fondos se desarrollan hábitats representativos de los fondos mediterráneos en un perfecto ...

  17. ESTUDIO TEORICO DE SELECTIVIDAD ANIONICA Y MECANISMO DE APERTURA Y CIERRE (GATING) EN CANALES DE CLORURO DE LA FAMILIA CLC.

    OpenAIRE

    BRIONES JARA, RODOLFO CESAR

    2006-01-01

    CIC es una familia de proteínas de membrana que transportan cloruros y desempeñan funciones como canales de cloruro o intercambiadores protón/cloruro. Estas proteínas, conservadas desde bacterias a humanos, son importantes para la fisiología celular y est 115p.

  18. Management of C-shaped canals: Two case reports

    Directory of Open Access Journals (Sweden)

    Nilesh Suryakant Kadam

    2013-01-01

    Full Text Available A C-shaped canal with varying configuration is commonly observed in single-rooted mandibular second molars. Cooke and Cox (1979 first documented the C-shaped canal in endodontic literature. The presence of high incidence of transverse anastomoses, lateral canals, and apical deltas makes it difficult to clean and seal the root canal system in these teeth. The main reason for failure in endodontic treatment of mandibular second molars is the inability to detect the presence of C-shaped canals prior to an endodontic therapy. This case report presents successful management of two rare cases of C-shaped canal configurations.

  19. Persistência do canal arterial e endarterite da artéria pulmonar

    Directory of Open Access Journals (Sweden)

    Rivera Ivan Romero

    1997-01-01

    Full Text Available Descrevemos uma paciente de sete anos com diagnóstico ecocardiográfico e confirmação cirúrgica de endarterite de artéria pulmonar, citada como complicação da persistência do canal arterial e ilustramos a necessidade de ressecção cirúrgica completa do processo infeccioso para evitar outras complicações, como embolia pulmonar.

  20. Function of lateral line canal morphology.

    Science.gov (United States)

    Klein, Adrian; Bleckmann, Horst

    2015-01-01

    Fish perceive water motions and pressure gradients with their lateral line. Lateral line information is used for prey detection, spatial orientation, predator avoidance, schooling behavior, intraspecific communication and station holding. The lateral line of most fishes consists of superficial neuromasts (SNs) and canal neuromasts (CNs). The distribution of SNs and CNs shows a high degree of variation among fishes. Researchers have speculated for decades about the functional significance of this diversity, often without any conclusive answers. Klein et al. (2013) examined how tubules, pore number and pore patterns affect the filter properties of lateral line canals in a marine teleost, the black prickleback (Xiphister atropurpureus). A preliminary mathematical model was formulated and biomimetic sensors were built. For the present study the mathematical model was extended to understand the major underlying principle of how canal dimensions influence the filter properties of the lateral line. Both the extended mathematical model and the sensor experiments show that the number and distribution of pores determine the spatial filter properties of the lateral line. In an environment with little hydrodynamic noise, simple and complex lateral line canals have comparable response properties. However, if exposed to highly turbulent conditions, canals with numerous widely spaced pores increase the signal to noise ratio significantly. © 2014 International Society of Zoological Sciences, Institute of Zoology/Chinese Academy of Sciences and Wiley Publishing Asia Pty Ltd.

  1. Análisis, diseño y construcción de un simulador de señales de paciente para ser usado en electrocardiografía, utilizando circuitos lineales

    OpenAIRE

    Murillo Sevillano, Begonia E.; Soria Heredia, Jaime A.; Yapur, Miguel

    2011-01-01

    Este simulador de señales de paciente para electrocardiografía, es capaz de generar una señal cardiaca normal, así como, por medio de uno de sus elementos constituyentes, se puede simular patologías cardíacas. El objetivo de este instrumento es lograr probar a satisfacción el funcionamiento de electrocardiógrafos, constituyéndose en una herramienta de gran ayuda tanto para el personal de la rama de la tecnología como de la medicina. Al conectarlo a un electrocardiógrafo se podrán obser...

  2. Study of root canal accessibility in human primary molars.

    Science.gov (United States)

    Aminabadi, Naser A; Farahani, Ramin M Z; Gajan, Esrafil B

    2008-03-01

    The aim of the present study was to provide a general scheme for pulpectomy of primary molars that may be useful for decision-making about negotiation of root canals and selection of appropriate instruments. A total of 160 vital primary molars in 85 patients (40 males, 45 females) aged 4-6 years were selected. After taking primary radiographs, local anesthesia was induced, and the teeth were isolated using a rubber dam. Canal accessibility index (CAI) and tooth accessibility index (TAI) were calculated according to initial file size. Mandibular first molars had either three canals (79.2%) or four canals (20.8%), and all second molars had four canals. Maxillary first molars had three canals and second molars had either three canals (70.9%) or four canals (29.1%). Lower accessibility of the mandibular first molar distobuccal root accounted for the lower accessibility of these teeth in comparison with mandibular second molars. While three-canal maxillary second molars were more accessible due to the lower accessibility of the distobuccal canal of the maxillary first molar, poor accessibility of the distal canal in four-canal second molars was responsible for the difficult accessibility of these teeth. In conclusion, it seems that the accessibility of a single canal in each tooth determines the difficulty of accessibility for any given tooth. Moreover, while primary second molars are more accessible than first molars, all of them are negotiable.

  3. Root canal debridement: an online study guide.

    Science.gov (United States)

    2008-05-01

    The Editorial Board of the Journal of Endodontics has developed a literature-based study guide of topical areas related to endodontics. This study guide is intended to give the reader a focused review of the essential endodontic literature and does not cite all possible articles related to each topic. Although citing all articles would be comprehensive, it would defeat the idea of a study guide. This section will present root canal debridement including subdivisions on canal access, canal debridement, orifice enlargement and preflaring, crown-down technique, balanced force, nickel titanium and other shape memory alloys, rotary engine-driven techniques, endodontic instruments, irrigation, electronic apex locators, sonics/ultrasonics, smear layer, and intracanal medicaments.

  4. Canal de Mensagens de Trânsito

    Directory of Open Access Journals (Sweden)

    Egon Cervieri Guterres

    2010-05-01

    Full Text Available Informe Setorial: O Canal de Mensagens de Trânsito (Traffic Message Channel - TMC é uma padronização internacional para a distribuição de informações (conteúdo sobre a situação do trânsito urbano local e inter-regional, em tempo real, de forma eletrônica e diretamente aos motoristas. Traz para os cidadãos, em mensagens eletrônicas simples e acessíveis, informações sobre congestionamentos, acidentes, obras na pista, problemas climáticos (alagamentos, asfalto escorregadio, nevoeiro... e desvios de rota, além de muitos outros eventos de trânsito, oferecendo, em linguagem padronizada de fácil compreensão, a descrição do incidente, área de efeito, duração esperada e, quando possível, caminhos alternativos para evitá-lo.

  5. Effect of two contemporary root canal sealers on root canal dentin microhardness.

    Science.gov (United States)

    Khallaf, Maram E

    2017-01-01

    Successful root canal treatment depends on proper cleaning, disinfecting and shaping of the root canal space. Pulpless teeth have lower dentin microhardness value compared to that of vital teeth. A material which can cause change in dentin composition may affect the microhardness. Thus the aim of this study was to evaluate and compare the effect of two root canal sealers on dentin microhardness. Forty two single rooted teeth were selected and divided into 3 equal groups; Apexit, iRootSP and control groups (n=14) Each group was then divided into 2 subgroups according to the post evaluation period; 1 week and 2 months (n=7). Root canal procedure was done in the experimental groups and obturation was made using either; Apexit, iRootSP or left unprepared and unobturated in the control group. Roots were sectioned transversely into cervical, middle and apical segments. The three sections of each root were mounted in a plastic chuck with acrylic resin. The coronal dentin surfaces of the root segments werepolished. Microhardness of each section was measured at 500 µm and 1000 µm from the canal lumen. Four way-ANOVA revealed that different tested sealer materials, canal third, measuring distance from the pulp and time as independent variables had statistically non significant effect on mean microhardness values (VHN) at p≤0.001. Among iRootSP groups there was a statistically significant difference between iRoot SP at coronal root portion (87.79±17.83) and iRoot SP at apical root portion (76.26±9.33) groups where (p=0.01). IRoot SP at coronal canal third had higher statistically significant mean microhardness value (87.79±17.83) compared to Apexit at coronal third (73.61±13.47) where (p=0.01). Root canal sealers do not affect dentin microhardness. Key words:Root canal, dentin, sealers, microhardness, bioceramic.

  6. Cochlear implant outcomes in patients with superior canal dehiscence

    NARCIS (Netherlands)

    Puram, Sidharth V.; Roberts, Daniel S.; Niesten, Marlien E F|info:eu-repo/dai/nl/377125202; Dilger, Amanda E.; Lee, Daniel J.

    2015-01-01

    Objective: To determine whether adult cochlear implant (CI) users with superior canal dehiscence syndrome (SCDS) or asymptomatic superior semicircular canal dehiscence (SCD) have different surgical, vestibular, and audiologic outcomes when compared to CI users with normal temporal bone anatomy.

  7. Surgical endodontic management of infected lateral canals of maxillary incisors.

    Science.gov (United States)

    Jang, Ji-Hyun; Lee, Jung-Min; Yi, Jin-Kyu; Choi, Sung-Baik; Park, Sang-Hyuk

    2015-02-01

    This case report presents surgical endodontic management outcomes of maxillary incisors that were infected via the lateral canals. Two cases are presented in which endodontically-treated maxillary central incisors had sustained lateral canal infections. A surgical endodontic treatment was performed on both teeth. Flap elevation revealed vertical bone destruction along the root surface and infected lateral canals, and microscopy revealed that the lateral canals were the origin of the lesions. After the infected lateral canals were surgically managed, both teeth were asymptomatic and labial fistulas were resolved. There were no clinical or radiographic signs of surgical endodontic management failure at follow-up visits. This case report highlights the clinical significance and surgical endodontic management of infected lateral canal of maxillary incisor. It is important to be aware of root canal anatomy variability in maxillary incisors. Maxillary central incisors infected via the lateral canal can be successfully managed by surgical endodontic treatment.

  8. Intradermal melanocytic nevus of the external auditory canal.

    Science.gov (United States)

    Alves, Renato V; Brandão, Fabiano H; Aquino, José E P; Carvalho, Maria R M S; Giancoli, Suzana M; Younes, Eduado A P

    2005-01-01

    Intradermal nevi are common benign pigmented skin tumors. Their occurrence within the external auditory canal is uncommon. The clinical and pathologic features of an intradermal nevus arising within the external auditory canal are presented, and the literature reviewed.

  9. Radiographic versus electronic root canal working length determination

    Directory of Open Access Journals (Sweden)

    Lumnije Kqiku

    2011-01-01

    Conclusions: The present ex vivo study showed that electronic root canal working length determination is not superior to radiographic methods. Both methods provided a good performance in determining the root canal working length.

  10. Report from the Panama Canal Stakeholder Working Group.

    Science.gov (United States)

    2013-03-01

    This project assists the Texas Department of Transportation (TxDOT) in assessing the potential impacts of the Panama Canal expansion on Texas ports and the landside transportation system. TxDOT formed a Panama Canal Stakeholder Working Group (PCSWG) ...

  11. Viscoelastic assessment of anal canal function using acoustic reflectometry

    DEFF Research Database (Denmark)

    Mitchell, Peter J; Klarskov, Niels; Telford, Karen J

    2012-01-01

    Anal acoustic reflectometry is a new reproducible technique that allows a viscoelastic assessment of anal canal function. Five new variables reflecting anal canal function are measured: the opening and closing pressure, opening and closing elastance, and hysteresis.......Anal acoustic reflectometry is a new reproducible technique that allows a viscoelastic assessment of anal canal function. Five new variables reflecting anal canal function are measured: the opening and closing pressure, opening and closing elastance, and hysteresis....

  12. Efectos ambientales en la agricultura por el uso de aguas residuales del canal de Chilhuacán, Atlixco, Puebla

    OpenAIRE

    Neri Ramírez Efraín

    2012-01-01

    La zona agrícola del canal Chilhuacán se riega con aguas residuales provenientes del río Nexapa, es altamente productiva en hortalizas, forrajes y ornamentales, pero con un riesgo implícito para suelos y cultivos, debido a que las aguas tienen contaminantes, principalmente metales pesados y alta salinidad. El objetivo de esta investigación fue: “Evaluar los efectos ambientales y sociales de la agricultura de riego ocasionados por el uso de aguas residuales del canal Chilhuacán...

  13. 75 FR 32275 - Regulated Navigation Area; Gulf Intracoastal Waterway, Inner Harbor Navigation Canal, Harvey...

    Science.gov (United States)

    2010-06-08

    ..., Inner Harbor Navigation Canal, Harvey Canal, Algiers Canal, New Orleans, LA AGENCY: Coast Guard, DHS...), Harvey Canal, and Algiers Canal during severe hurricane conditions. Vessels will not be permitted to stay... communities within the IHNC, Harvey, and Algiers Canals from potential hazards associated with vessels being...

  14. 21 CFR 872.3820 - Root canal filling resin.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Root canal filling resin. 872.3820 Section 872...) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3820 Root canal filling resin. (a) Identification. A root canal filling resin is a device composed of material, such as methylmethacrylate, intended...

  15. 5 CFR 550.714 - Panama Canal Commission employees.

    Science.gov (United States)

    2010-01-01

    ... 5 Administrative Personnel 1 2010-01-01 2010-01-01 false Panama Canal Commission employees. 550... PAY ADMINISTRATION (GENERAL) Severance Pay § 550.714 Panama Canal Commission employees. (a) Notwithstanding any other provisions of this subpart, an employee separated from employment with the Panama Canal...

  16. Maxillary First Premolar with Three Root Canals: A Case Report ...

    African Journals Online (AJOL)

    ... the tooth is needed to ensure a proper endodontic treatment. This article reports a rare finding of three canals in a maxillary first premolar with non well defined root outline radiographically during an elective root canal treatment. Keywords: Maxillary First Premolar, Endodontic Treatment, Elective, Root Canal Morphology ...

  17. Lumbar Vertebral Canal Diameters in Adult Ugandan Skeletons ...

    African Journals Online (AJOL)

    Background: Normal values of lumbar vertebral canal diameters are useful in facilitating diagnosis of lumbar vertebral canal stenosis. Various studies have established variation on values between different populations, gender, age, and ethnic groups. Objectives: To determine the lumbar vertebral canal diameters in adult ...

  18. The crazy project – Canal Istanbul

    Directory of Open Access Journals (Sweden)

    Seda Kundak

    2011-10-01

    Full Text Available It was late April 2011 when “the Crazy Project - Canal Istanbul” was proposed by the Prime Minister of Turkey, during his election campaign.  Although the idea of an artificial canal is not new, since it is initiated without any consensus between the people and institutions in Istanbul, the project immediately set a large number of debates. These vary from the legitimacy of decentralization of governance, to potential impacts of the canal on international politics, economy, environment and urban life.  Regarding past infrastructure projects in Istanbul, such large scale investments have caused extensive acceleration in construction sector in one hand and social and economic shifts on the other.  In this paper, the Canal Istanbul Project is evaluated according to basic motivations and claims of the PM, multi-perspective view through challenges and limitation that the project is likely to face with and speculations on implementation approach. The final discussion on the project is based on benefits/losses of Istanbul once the project will be implemented.

  19. Cancer of the external auditory canal

    DEFF Research Database (Denmark)

    Nyrop, Mette; Grøntved, Aksel

    2002-01-01

    OBJECTIVE: To evaluate the outcome of surgery for cancer of the external auditory canal and relate this to the Pittsburgh staging system used both on squamous cell carcinoma and non-squamous cell carcinoma. DESIGN: Retrospective case series of all patients who had surgery between 1979 and 2000. M...

  20. Infrared typmanic tempature and ear canal morphology

    NARCIS (Netherlands)

    Daanen, H.A.M.

    2006-01-01

    Several publications indicate that the infrared tympanic temperature (IRTT) underestimates the core temperature of the body when the ear canal is long, curvy and narrow. In order to quantify these observations, a study was performed in 10 subjects. The IRTT was determined and compared to the

  1. The Panama Canal and Social Justice.

    Science.gov (United States)

    Wilde, Margaret D., Ed.

    The booklet, designed to explore the issues of international justice in the context of the Gospel, reviews relations between the United States and Panama. It includes background materials and a study guide for parish leaders and other educators. The central question pertaining to the Panama Canal concerns the rights of the United States according…

  2. Residuos de antimicrobianos en canales de vacas

    National Research Council Canada - National Science Library

    GESCHE, E; EMILFORK, C

    1998-01-01

    Con la finalidad de conocer la presencia de residuos de antibióticos y sulfamidas en animales de abasto, se analizaron las canales de 300 vacas faenadas en una Planta Faenadora de Carnes de la X Región de Chile...

  3. Suficiência amostral para mudas de cafeeiro cv. Rubi

    Directory of Open Access Journals (Sweden)

    Patriciani Estela Cipriano

    2012-04-01

    Full Text Available O número de plantas por parcela experimental é de extrema importância para a precisão dos resultados. O objetivou deste trabalho é encontrar o tamanho ótimo para experimentos de mudas de cafeeiro da cultivar Rubi MG 1192. O experimento foi instalado no Instituto Federal de Educação, Ciência e Tecnologia do Sul de Minas Gerais (IFSULDEMINAS, campus Machado. As plantas foram dispostas em 14 fileiras com 14 plantas em cada linha. Foram descartadas a primeira e última fileira e a primeira e última linha, as quais tiveram função de bordadura. Utilizaram-se, portanto, 144 mudas que individualmente caracterizavam as unidades básicas (UB. As avaliações ocorreram quando as plantas atingiram o sexto par de folhas definitivo e as variáveis respostas foram coletadas. Cada uma das 144 UB foi utilizada para simular 14 diferentes tamanhos de parcelas de 1UB até 72UB. Não foi considerada a forma das parcelas. Para cada um desses agrupamentos foi calculado o coeficiente de variação médio. Verificou-se que o tamanho ótimo de parcela útil para experimentos com mudas de café da cultivar Rubi MG 1192 varia de 2 a 8 mudas por parcela, de acordo com a variável em estudo.

  4. Semiconductor laser irradiation improves root canal sealing during routine root canal therapy

    OpenAIRE

    Su, Dandan; Hu, Xingxue; Wang, Dashan; Cui, Ting; Yao, RuYong; Sun, Huibin

    2017-01-01

    Objective To evaluate the effect of semiconductor laser irradiation on root canal sealing after routine root canal therapy (RCT). Methods Sixty freshly extracted single-rooted human teeth were randomly divided into six groups (n = 10). The anatomic crowns were sectioned at the cementoenamel junction and the remaining roots were prepared endodontically with conventional RCT methods. Groups A and B were irradiated with semiconductor laser at 1W for 20 seconds; Groups C and D were ultrasonically...

  5. MR determination of neonatal spinal canal depth

    Energy Technology Data Exchange (ETDEWEB)

    Arthurs, Owen, E-mail: owenarthurs@uk2.net [Centre for Cardiovascular MR, Great Ormond Street Hospital for Children, London WC1N 3JH (United Kingdom); Thayyil, Sudhin, E-mail: s.thayyil@ucl.ac.uk [Academic Neonatology, Institute for Women' s Health, London WC1E 6AU (United Kingdom); Wade, Angie, E-mail: a.wade@ucl.ac.uk [Centre for Paediatric Epidemiology and Biostatistics, UCL Institute of Child Health, London (United Kingdom); Chong, W.K., E-mail: Kling.Chong@gosh.nhs.uk [Paediatric Neuroradiology, Great Ormond Street Hospital for Children, London (United Kingdom); Sebire, Neil J., E-mail: Neil.Sebire@gosh.nhs.uk [Histopathology, Great Ormond Street Hospital for Children, London WC1E 6AU (United Kingdom); Taylor, Andrew M., E-mail: a.taylor76@ucl.ac.uk [Centre for Cardiovascular MR, Cardiorespiratory Unit, Great Ormond Street Hospital for Children and UCL Institute of Cardiovascular Science, London WC1E 6AU (United Kingdom)

    2012-08-15

    Objectives: Lumbar punctures (LPs) are frequently performed in neonates and often result in traumatic haemorrhagic taps. Knowledge of the distance from the skin to the middle of the spinal canal (mid-spinal canal depth - MSCD) may reduce the incidence of traumatic taps, but there is little data in extremely premature or low birth weight neonates. Here, we determined the spinal canal depth at post-mortem in perinatal deaths using magnetic resonance imaging (MRI). Patients and methods: Spinal canal depth was measured in 78 post-mortem foetuses and perinatal cases (mean gestation 26 weeks; mean weight 1.04 kg) at the L3/L4 inter-vertebral space at post-mortem MRI. Both anterior (ASCD) and posterior (PSCD) spinal canal depth were measured; MSCD was calculated and modelled against weight and gestational age. Results: ASCD and PSCD (mm) correlated significantly with weight and gestational age (all r > 0.8). A simple linear model MSCD (mm) = 3 Multiplication-Sign Weight (kg) + 5 was the best fit, identifying an SCD value within the correct range for 87.2% (68/78) (95% CI (78.0, 92.9%)) cases. Gestational age did not add significantly to the predictive value of the model. Conclusion: There is a significant correlation between MSCD and body weight at post-mortem MRI in foetuses and perinatal deaths. If this association holds in preterm neonates, use of the formula MSCD (mm) = 3 Multiplication-Sign Weight (kg) + 5 could result in fewer traumatic LPs in this population.

  6. Cervical spinal canal narrowing in idiopathic syringomyelia

    Energy Technology Data Exchange (ETDEWEB)

    Struck, Aaron F. [Massachusetts General Hospital, Department of Neurology, Boston, MA (United States); Carr, Carrie M. [Mayo Clinic, Department of Radiology, Rochester, MN (United States); Shah, Vinil [University of California San Francisco, Department of Radiology, San Francisco, CA (United States); Hesselink, John R. [University of California San Diego, Department of Radiology, San Diego, CA (United States); Haughton, Victor M. [University of Wisconsin, Department of Radiology, Madison, WI (United States)

    2016-08-15

    The cervical spine in Chiari I patient with syringomyelia has significantly different anteroposterior diameters than it does in Chiari I patients without syringomyelia. We tested the hypothesis that patients with idiopathic syringomyelia (IS) also have abnormal cervical spinal canal diameters. The finding in both groups may relate to the pathogenesis of syringomyelia. Local institutional review boards approved this retrospective study. Patients with IS were compared to age-matched controls with normal sagittal spine MR. All subjects had T1-weighted spin-echo (500/20) and T2-weighted fast spin-echo (2000/90) sagittal cervical spine images at 1.5 T. Readers blinded to demographic data and study hypothesis measured anteroposterior diameters at each cervical level. The spinal canal diameters were compared with a Mann-Whitney U test. The overall difference was assessed with a Friedman test. Seventeen subjects were read by two reviewers to assess inter-rater reliability. Fifty IS patients with 50 age-matched controls were studied. IS subjects had one or more syrinxes varying from 1 to 19 spinal segments. Spinal canal diameters narrowed from C1 to C3 and then enlarged from C5 to C7 in both groups. Diameters from C2 to C4 were narrower in the IS group (p < 0.005) than in controls. The ratio of the C3 to the C7 diameters was also smaller (p = 0.004) in IS than controls. Collectively, the spinal canal diameters in the IS were significantly different from controls (Friedman test p < 0.0001). Patients with IS have abnormally narrow upper and mid cervical spinal canal diameters and greater positive tapering between C3 and C7. (orig.)

  7. Cervical spinal canal narrowing in idiopathic syringomyelia.

    Science.gov (United States)

    Struck, Aaron F; Carr, Carrie M; Shah, Vinil; Hesselink, John R; Haughton, Victor M

    2016-08-01

    The cervical spine in Chiari I patient with syringomyelia has significantly different anteroposterior diameters than it does in Chiari I patients without syringomyelia. We tested the hypothesis that patients with idiopathic syringomyelia (IS) also have abnormal cervical spinal canal diameters. The finding in both groups may relate to the pathogenesis of syringomyelia. Local institutional review boards approved this retrospective study. Patients with IS were compared to age-matched controls with normal sagittal spine MR. All subjects had T1-weighted spin-echo (500/20) and T2-weighted fast spin-echo (2000/90) sagittal cervical spine images at 1.5 T. Readers blinded to demographic data and study hypothesis measured anteroposterior diameters at each cervical level. The spinal canal diameters were compared with a Mann-Whitney U test. The overall difference was assessed with a Friedman test. Seventeen subjects were read by two reviewers to assess inter-rater reliability. Fifty IS patients with 50 age-matched controls were studied. IS subjects had one or more syrinxes varying from 1 to 19 spinal segments. Spinal canal diameters narrowed from C1 to C3 and then enlarged from C5 to C7 in both groups. Diameters from C2 to C4 were narrower in the IS group (p < 0.005) than in controls. The ratio of the C3 to the C7 diameters was also smaller (p = 0.004) in IS than controls. Collectively, the spinal canal diameters in the IS were significantly different from controls (Friedman test p < 0.0001). Patients with IS have abnormally narrow upper and mid cervical spinal canal diameters and greater positive tapering between C3 and C7.

  8. MAXILLARY FIRST PREMOLARS WITH THREE ROOT CANALS: TWO CASE REPORTS

    Directory of Open Access Journals (Sweden)

    Zeliha UĞUR

    2017-10-01

    Full Text Available It is very important that the dentists have sufficient information about possible variations in the expected root canal configurations in order to achieve success in endodontic treatment. In addition to having adequate knowledge on the variations of the root canal anatomy, periapical radiographs from different angles, careful examination of the pulp chamber floor, and use of dental operation microscope during the procedure are also important factors that contribute to the diagnosis of the additional roots and canals. The aims of this article are to present the diagnostic approach and root canal treatments of two maxillary first premolar teeth with three canals in two patients.

  9. Simulación de una red Grid con máquinas virtuales para crear un entorno de aprendizaje de la computación de alto desempeño

    Directory of Open Access Journals (Sweden)

    Edwin Eduardo Millán-Rojas

    2016-01-01

    Full Text Available Presenta una metodología de construcción de una plataforma para simular una red Grid con máquinas virtuales, con el objetivo de crear entornos virtuales que contribuyan a los procesos de aprendizaje. El diseño utilizado para el desarrollo está basado en un prototipo que contribuye a generar un entorno de simulación de bajo costo a través de la computación de alto desempeño. Como resultado de la investigación se obtuvo un conjunto de máquinas virtuales que pueden ser desplegadas en cualquier equipo de cómputo para simular un entorno Grid; además, se presenta la forma de la configuración de esta red para ser parte integral de la construcción y ejecución de la plataforma como instrumento válido para la enseñanza de la computación de alto desempeño a un bajo coste de hardware y la simulación de los servicios Grid sobre la plataforma.

  10. Mobilização do osso pisiforme no tratamento da neuropraxia do nervo ulnar no canal de Guyon: relato de caso Pisiform bone mobilization for treating ulnar nerve neuropraxia at Guyon's canal: case report

    Directory of Open Access Journals (Sweden)

    Júlio Guilherme Silva

    2009-12-01

    Full Text Available As neuropraxias do nervo ulnar são lesões bastante freqüentes que provocam efeitos deletérios, como diminuição de força muscular e parestesias; geralmente ocorrem no nível do epicôndilo medial e do túnel ulnar (canal de Guyon. São escassos os relatos referentes a técnicas de terapia manual para compressões do nervo ulnar no canal de Guyon. Este trabalho relata o uso da técnica de mobilização do pisiforme na compressão do nervo ulnar no canal de Guyon de um homem que sofreu luxação do punho direito aos 8 anos e, aos 25, queixava-se de um deficit para adução do dedo mínimo, que atrapalhava a realização de algumas atividades de vida diária. O paciente foi submetido a uma única sessão de mobilização articular do pisiforme. Após a aplicação da técnica, o sinal positivo do teste foi eliminado, restabelecendo-se a função de adução do 5o dedo. Embora carecendo de maior fundamentação teórica, pode-se afirmar que a técnica usada, de mobilização articular do osso pisiforme, é eficaz para melhora do quadro de paresia por neuropraxia do nervo ulnar no canal de Guyon.A common ulnar nerve neuropraxia is lesion that may result in muscle strength decrease and/or paresthesia; it usually takes place at medial epicondyle level and the ulnar tunnel (Guyon's canal. Studies on manual therapy techniques for ulnar nerve compression in Guyon's canal are scarce. This paper reports the use of a technique of pisiform bone mobilization for relieving ulnar nerve compression in Guyon's canal, in a man who had suffered a luxation of the right wrist at the age of 8 and, at 25, complained of adduction deficit of the fifth finger that interfered in his daily life activities. He was submitted to one session of pisiform mobilization; after the session, the positive test sign was eliminated, thus restoring the fifth finger function. Though lacking further grounding, it may be said that the technique used, of mobilizing the pisiform bone

  11. A new system for classifying tooth, root and canal anomalies.

    Science.gov (United States)

    Ahmed, H M A; Dummer, P M H

    2017-10-12

    Understanding the normal anatomical features as well as the more unusual developmental anomalies of teeth, roots and root canals is essential for successful root canal treatment. In addition to various types of root canal configuration and accessory canal morphology, a wide range of developmental tooth, root and canal anomalies exists, including C-shaped canals, dens invaginatus, taurodontism, root fusion, dilacerations and palato-gingival grooves. There is a direct association between developmental anomalies and pulp and periradicular diseases that usually require a multidisciplinary treatment approach to achieve a successful outcome. A number of classifications have categorized tooth, root and canal anomalies; however, several important details are often missed making the classifications less than ideal and potentially confusing. Recently, a new coding system for classifying root, root canal and accessory canal morphology has been introduced. The purpose of this article is to introduce a new system for classifying tooth, root and canal anomalies for use in research, clinical practice and training, which can serve as complementary codes to the recently described system for classifying root, as well as main and accessory canal morphology. © 2017 International Endodontic Journal. Published by John Wiley & Sons Ltd.

  12. [Measurements of semicircular canal space direction with MRI].

    Science.gov (United States)

    Yang, Xiaokai; Wu, Shuzhi; Ye, Hua

    2015-10-01

    Measure the space direction of semicircular canals to provide the anatomical basis for the diagnosis and treatment of BPPV. We calculated angles among semicircular canals of 24 patients using MRI scaning with 3D-CISS sequence. The angle between the left and right posterior semicircular canals was 106.61 degress ± 8.58 degrees, so the angle among the posterior semicircular canals and sagittal head plane was 53.31 degrees ± 4.29 degrees. Pairs of contralateral synergistic canal planes were not parallel, forming 171.67 degrees ± 4.36 degrees between the left and right horizontal semicircular canal planes, 154.37 degrees ± 10.87 degrees between the left posterior and right anterior semicircular canal planes and 156.84 degrees ± 9.34 degrees between the right posterior and left anterior semicircular canal planes. Our measurement of the angles among semicircular canals coincided with those of previous reports. The angles between contralateral synergistic canal planes were close to parallel, but the angle between the posterior semicircular canals and sagittal head plane was great than 45 degrees that traditionally thought to be.

  13. Preparación de canales curvos y calcificados

    Directory of Open Access Journals (Sweden)

    Karen Sofia Gallego Lopez

    2013-10-01

    Full Text Available ResumenLa preparación durante el tratamiento endodóntico consiste en la correcta limpieza y conformación del sistema de conductos radiculares, y que conserve siempre su forma original. Al finalizar la preparación, se debe obtener un conducto con conicidad uniforme y con un tope apical, que permita un selle hermético al momento de la obturación. Se debe tener en cuenta la dificultad para lograr resultados satisfactorios sobre todo en conductos curvos y calcificados debido a la complejidad de éstos. Las técnicas implementadas y el instrumental adecuado para la preparación de conductos, han sido muchos con el fin de minimizar los errores durante la preparación. No obstante, ninguna técnica ni instrumental por sí solo resulta ideal en la prevención de estos errores; es necesario el cumplimiento de algunos principios básicos durante la preparación de estos conductos, tales como la correcta preparación coronal, el uso continuo de irrigantes y agentes quelantes, el mantenimiento de la permeabilidad, el limado anticurvatura y la doble conicidad. La incorrección de estos principios conlleva a errores, los cuales dificultan el éxito del tratamiento endodóntico. Los avances de la ciencia y el advenimiento de los instrumentos de níquel-titanio, han logrado facilitar el tratamiento de endodoncia, tanto que ya no es considerado como anteriormente se le atribuía que era un procedimiento difícil, lo importante predecir la orientación y anatomía del conducto antes de emplear técnicas o instrumentales, ya que un error en ellas nos llevará al fracaso del tratamiento. (DUAZARY 2011, 66 - 73AbstractThe preparation for the endodontic treatment is proper cleaning and shaping the root canal system, and always keep its original shape. After the preparation, must be obtained through uniform and tapered with an apical stop, allowing a tight seal when the seal. It must take into account the difficulty of achieving satisfactory results especially

  14. El medio-portal y los canales de actualidad

    Directory of Open Access Journals (Sweden)

    Dra. Elvira García de Torres

    2002-01-01

    Full Text Available El presente artículo analiza el reto que Internet ha supuesto para los medios de comunicación tradicionales. La autora estudia cómo los medios informativos enlínea se han convertido en "un híbrido entre medios tradicionales con características propias de la digitalidad y servicios y contenidos propios de los portales". Así surge el medio-portal, mientras que los portales crean canales de actualidad para evitar la pérdida de usuario. El artículo recoge las principales diferencias en el tratamiento de la información por parte de ambos medios.ABSTRACTThis article analyses the challenge that Internet has involved to traditional mass media. The author thinks about how enlínea media have evolved to a hybrid between traditional media with digital characteristics and contents of main doors. The "medio-portal" begins, whereas main doors create channels of news to prevent the loss of users. This article collects the main informative differences between both media.

  15. FAUNA ICTICA DE UN SISTEMA FLUVIAL MODIFICADO POR CANALES DE REGADIO. COMPARACION DE LAS COMUNIDADES DE PECES ASOCIADAS AL CAUCE NATURAL Y CANALES ARTIFICIALES

    OpenAIRE

    HABIT CONEJEROS, EVELYN MARIANA

    1997-01-01

    El aumento en la presión de uso de los recursos naturales ha provocado modificaciones en los sistemas fluviales, entre los cuales se cuenta la construcción de canales artificiales de riego. Estos ambientes constituyen espacios factibles de ser colonizados por especies acuáticas, tales como los peces. Hasta ahora se desconocía en Chile las características de estas nuevas comunidades, su estructura, relación con el río, su factibilidad de uso para fines productivos (acuaculturales), y las...

  16. Niveles optimos biologicos de lisina para cerdos en crecimiento-finalizacion

    National Research Council Canada - National Science Library

    Martinez-Aispuro, Jose Alfredo; Figueroa-Velasco, Jose Luis; Cordero-Mora, Jose Luis; Ruiz-Flores, Agustin; Sanchez-Torres, Maria Teresa; Ortega-Cerrilla, Maria Esther; Narciso-Gaytan, Carlos

    2014-01-01

    El objetivo del presente trabajo fue determinar el nivel optimo de lisina total para las variables productivas, caracteristicas de la canal y concentracion de urea en plasma de cerdos en crecimiento y finalizacion...

  17. Análise comparativa entre instrumentação rotatória (GT, manual e associação de ambas no preparo de canais achatados Comparative analysis of rotatory (GT and manual root canal preparation and association of both techniques in instrumentation of flattened root canals

    Directory of Open Access Journals (Sweden)

    Silvana Beltrami Gonçalves

    2003-03-01

    Full Text Available A instrumentação do canal radicular tem sido considerada uma das fases mais importantes do tratamento endodôntico, portanto muitas técnicas e instrumentos têm sido desenvolvidos para esse fim. O propósito desse estudo foi avaliar a limpeza de canais radiculares instrumentados com três diferentes técnicas. Foram selecionados trinta incisivos inferiores, onde a abertura coronária foi realizada. Posteriormente, os canais foram preenchidos com tinta nanquim (corante, previamente acondicionada em tubetes anestésicos, sendo a mesma levada ao interior do canal radicular com auxílio de uma seringa carpule e uma agulha para anestesia. Após 48 horas, tempo esperado para que o corante secasse no canal, os dentes foram divididos em três grupos: G1 - instrumentação rotatória com GT; G2 - instrumentação manual e G3 - associação de ambas (mista. Após a instrumentação, os dentes foram seccionados longitudinalmente e realizada a avaliação da limpeza dos canais, através da remoção de corante nos terços cervical, médio e apical. Os resultados demonstraram que não houve diferença estatisticamente significante na limpeza do canal entre as três técnicas de instrumentação estudadas, nos três terços avaliados.Root canal preparation has been considered one of the most important steps in root canal therapy, thus many techniques and instruments have been developed. The aim of this study was to evaluate the cleaning of the root canal through three different instrumentation techniques. Thirty mandibular incisors were selected and submitted to lingual access cavities. Afterwards, the canals were filled with India ink dye previously stored in carpules, which was inserted into the root canal by means of anesthetic syringe and anesthetic needles. After 48 hours, during which the dye was allowed to dry inside the root canal, the teeth were divided in three groups: G1- GT rotatory instrumentation; G2- manual instrumentation; G3- association

  18. Gradually varied flow in compound open channels; Flujo gradualmente variado en canales de seccion compuesta

    Energy Technology Data Exchange (ETDEWEB)

    Sotela Avila, Gilberto [Universidad Nacional Autonoma de Mexico (Mexico)

    2001-03-01

    The author shows that the computation of gradually-varied-flow profiles in prismatic compound channels involves the solution of the dynamic equation, but using the compound channel Froude number defined by Blalock and Sturm. The same equation is used for non-prismatic channels by dividing the channel into short reaches and carrying the computation step by step through an iterative process. [Spanish] El autor demuestra que los perfiles del flujo gradualmente variado en canales prismaticos de seccion compuesta se pueden determinar mediante la integracion de la llamada ecuacion dinamica, pero usando el numero de Froude definido por Blalock y Sturm para este tipo de canales. Cuando no son prismaticos, tambien se aplica la ecuacion de la energia por tramos y el calculo sigue un proceso iterativo una vez definidos los tirantes criticos multiples y la zona en que se desarrolla el perfil.

  19. Problemas Del Pollo De Engorde Antes Y Después Del Beneficio (Pollo En Canal). 1º Parte

    OpenAIRE

    Sandra Lissette Ricaurte Galindo M.V.Z.

    2005-01-01

    Cuando los pollos llegan a la planta necesitan una ventilación adecuada en la zona de retención para minimizar la mortalidad y la pérdida excesiva de peso vivo. Los pollos que llegan deben ser programados para el procesamiento dentro de las 8 a 12 horas después de haber comido por última vez. De esta manera disminuye la cantidad de material que podría contaminar potencialmente la canal durante el procesamiento permitiendo tiempo suficiente para que el intestino se vacíe. Los pollos que quedan...

  20. Evaluation of accessory furcation canals of permanent mandibular molars using radiography and clearing = Avaliação do canal cavo-interradicular em molares inferiores permanentes através de Rx e diafanização

    Directory of Open Access Journals (Sweden)

    Harb, Leandro José Corrêa

    2010-01-01

    Full Text Available Objetivo: Avaliar a presença do canal cavo-interradicular em molares inferiores permanentes através de radiografias e diafanização. Metodologia: A amostra foi constituída por 344 molares inferiores re-hidratados, preparados e armazenados individualmente em recipientes de vidro. A presença do canal cavo-interradicular foi investigada por um único operador treinado usando lupa (4x para as radiografias e microscópio óptico odontológico (30x para as amostras diafanizadas. Microscopia eletrônica de varredura (MEV foi usada para verificar diferenças morfológicas do assoalho pulpar. Resultados: A análise radiográfica mostrou que 9% das amostras tinham uma zona levemente radiolúcida, 2% mostravam uma imagem sugestiva, e 89% das amostras não tinham nenhuma evidência. Pela diafanização, o canal não foi encontrado nas amostras avaliadas. Pela MEV, as amostras recém extraídas mostraram com canalículos dentinários uniformes; as demais apresentaram pequenos sítios com canalículos uniformes. Conclusão: O exame radiográfico não foi o melhor método de diagnóstico; a diafanização é um excelente método avaliativo, pois permite a visualização tridimensional da anatomia interna dental em pesquisas in vitro

  1. Politics and soccer in the film through the lens of newsreel Canal 100 Política e futebol no cinema através das lentes do cinejornal Canal 100

    Directory of Open Access Journals (Sweden)

    Paulo Roberto de Azevedo Maia

    2009-04-01

    Full Text Available This document discusses the historical route and the establishment of language of Canal 100, a movie news periodical. The format of the news movie series was studied for a better understanding of its narrative structure and especially the images related to soccer, responsible for the permanence of Canal 100 in the memory of several generations. To this end, we analyzed 42 editions, 55 cin script and collected 26 articles of the printing press, studying the period of 1959 up 1986. O artigo discute a trajetória histórica e a constituição da linguagem do cinejornal Canal 100. O formato do cinejornal foi estudado para melhor compreensão da sua estrutura narrativa e, particularmente, as imagens relativas ao futebol, responsáveis pela manutenção do Canal 100 na memória de algumas gerações. Para tanto, foram analisadas 42 edições, 55 roteiros e coletados 26 artigos da grande imprensa, cobrindo o período de 1959 a 1986.

  2. Root Canal Filling after Revascularization/Revitalization.

    Science.gov (United States)

    Plascencia, Hugo; Cruz, Álvaro; Díaz, Mariana; Jiménez, Ana Laura; Solís, Rodrigo; Bernal, Cesar

    Revascularization/revitalization therapy is considered an alternative procedure for management of teeth with an immature apex and necrotic pulp, mainly when root development is interrupted in the early phases of formation. However, this clinical treatment protocol should be considered a permanent procedure? A maxillary central incisor with a previous and successful RR treatment was intentionally filled with a biocompatible material with the periapical tissues due to the patient's lack of adherence to the follow-up protocol. The 20-month follow-up showed absence of clinical, radiological and tomographic signs and symptoms of an endodontic re-infection. This case demonstrates that once the increased thickening of the canal walls, incrementing the root length, apical closure and the total resolution of the apical lesion are observed, the main canal of a previously treated tooth with an RR procedure can be filled.

  3. Squamous cell carcinoma of the anal canal.

    LENUS (Irish Health Repository)

    Martin, F T

    2012-01-31

    Squamous cell carcinoma ofthe anal canal represents 1.5% of all malignancies affectingthe gastrointestinal tract. Over the past 20 years dramatic changes have been seen in both the epidemiological distribution of the disease and in the therapeutic modalities utilised to manage it. CLINICAL MANAGEMENT: Historically abdominoperineal resection had been the treatment of choice with local resection reserved for early stage disease. Work by Nigro et al. has revolutionised how we currently manage carcinoma of the anal canal, demonstrating combined modality chemoradiotherapy as an appropriate alternative to surgical resection with the benefit of preserving sphincter function. Surgery is then reserved for recurrent disease with salvage abdominoperineal resection. This article reviews current literature and highlights the changing therapeutic modalities with selected clinical cases

  4. Neuronal hyperplasia in the anal canal

    DEFF Research Database (Denmark)

    Fenger, C; Schrøder, H D

    1990-01-01

    In a consecutive series of minor surgical specimens from the anal canal, neuronal hyperplasia was found in nine of 56 haemorrhoidectomy specimens and in four of 23 fibrous polyps. In an additional series of 14 resections of the anal canal, neuronal hyperplasia was present in six cases, of which...... five showed haemorrhoids. In all cases, neuronal hyperplasia was located in the submucosa beneath squamous epithelium and extended over an area from 5 to 12 mm. Immunohistochemically, the foci of hyperplasia were found to consist of both neuronal and Schwann cell components. Staining for vasoactive...... intestinal peptide, neuropeptide Y and calcitonin gene related peptide, did not demonstrate any increased terminal density. It is suggested that anal neuronal hyperplasia in these cases represents an acquired lesion due to local mechanical influence....

  5. The shape of the human lumbar vertebral canal A forma do canal vertebral lombar humano

    Directory of Open Access Journals (Sweden)

    Edmundo Zarzur

    1996-09-01

    Full Text Available Literature on the anatomy of the human vertebral column characterizes the shape of the lumbar vertebral canal as triangular. The purpose of the present study was to determine the precise shape of the lumbar vertebral canal. Ten lumbar vertebral columns of adult male cadavers were dissected. Two transverse sections were performed in the third lumbar vertebra. One section was performed at the level of the lower border of the ligamenta flava, and the other section was performed at the level of the pedicles. The shape of the lumbar vertebral canal at the level of the pedicles tends to be oval or circular, whereas the shape of the lumbar vertebral canal at the level of the lower border of the ligamenta flava is triangular. Thus, the shape of the human lumbar vertebral canal is not exclusively triangular, as reported in the literature. It is related to the level of the transversal section performed on the lumbar vertebra. This finding should be taken into consideration among factors involved in the spread of solutions introduced into the epidural space.A literatura sobre a anatomia da coluna vertebral descreve como sendo triangular o formato do canal vertebral na região lombar. O objetivo deste estudo é determinar a real forma do canal da coluna vertebral lombar.Dez colunas vertebrais de cadáveres de homens adultos foram dissecadas. Dois cortes transversais foram executados na terceira vértebra lombar. Um corte foi feito no nível das bordas inferiores de dois ligamentos amarelos vizinhos e o outro corte foi transversal, no nível dos pedículos. A forma do canal vertebral variou: no nível dos pedículos ela tende a ser oval ou circular e junto às bordas inferiores dos ligamentos amarelos passa a ser triangular. Portanto, a forma do canal vertebral lombar não é somente triangular; ela depende do nível em que se faz o corte transversal da vértebra. Estes achados devem ser levados em consideração entre os fatores envolvidos na difusão das

  6. Koebner phenomenon of the ear canal skin.

    LENUS (Irish Health Repository)

    Young, O

    2009-02-01

    The Koebner phenomenon originally described the appearance of psoriatic lesions in the uninvolved skin of patients with psoriasis as a consequence of trauma. We describe a case of concurrent lichen planus and sarcoidosis in the auditory canal, which represents an unusual manifestation of the Koebner phenomenon. This is the first case of concurrent lichen planus and sarcoidosis in the head and neck region and highlights the need for biopsy to allow accurate histopathological diagnosis and treatment.

  7. Koebner phenomenon of the ear canal skin.

    LENUS (Irish Health Repository)

    Young, O

    2012-02-01

    The Koebner phenomenon originally described the appearance of psoriatic lesions in the uninvolved skin of patients with psoriasis as a consequence of trauma. We describe a case of concurrent lichen planus and sarcoidosis in the auditory canal, which represents an unusual manifestation of the Koebner phenomenon. This is the first case of concurrent lichen planus and sarcoidosis in the head and neck region and highlights the need for biopsy to allow accurate histopathological diagnosis and treatment.

  8. Root canal filling using Resilon: a review.

    LENUS (Irish Health Repository)

    Shanahan, D J

    2011-07-01

    Root canal treatment is achieved by chemo-mechanical debridement of the root canal system followed by filling. The filling material \\'entombs\\' residual bacteria and acts as a barrier which prevents the entrance of oral microorganisms and reinfection of the root canal system through microleakage. However, filling with contemporary root filling materials such as gutta-percha offers limited long-term resistance to microorganisms; as a result other materials such as Resilon have been investigated as alternatives. The aim of this review was to analyse the literature to consider whether Resilon is a suitable root canal filling material. A MEDLINE and Cochrane library search including various keyword searches identified several papers which investigated or discussed Resilon or RealSeal\\/Epiphany. Analysis of the literature demonstrated that the bulk of the literature is in vitro in nature, based largely on leakage-type studies, and demonstrates a wide variety of methodologies with conflicting findings; as a result meaningful conclusions are difficult. Within the limit of these in vitro studies Resilon appears to perform adequately in comparison to gutta-percha, however, as a result of the questionable merit of such studies, it cannot presently be considered an evidence-based alternative to the current gold standard gutta-percha. It is imperative that before Resilon is considered as a replacement material, a better understanding of the physical properties of the resin sealer and the reality of the adhesive \\'monoblock\\' are elucidated. The literature also demonstrates a paucity of quality long-term clinical outcome studies which will need to be addressed before firm conclusions can be reached.

  9. Carotid canal dehiscence in the human skull

    Energy Technology Data Exchange (ETDEWEB)

    Pastor Vazquez, J.F.; Gil Verona, J.A. [Department of Anatomy, Faculty of Medicine, University of Valladolid, Ramon y Cajal, 7, E-47005 Valladolid (Spain); Garcia Porrero, M. [Department of Radiology, Faculty of Medicine, University of Valladolid (Spain)

    1999-06-01

    Abnormalities of the floor of the carotid canal have been studied in 538 skulls. These abnormalities range from a fissure to total absence of the floor. This variation may be caused by abnormalities of the internal carotid artery or deficiencies in ossification of the skull base. CT suggests that these changes should be taken into account by surgeons working on the skull base. (orig.) With 4 figs., 8 refs.

  10. Roentgenographic study of the mandibular canal

    Energy Technology Data Exchange (ETDEWEB)

    Ahn, Hyung Kyu [Dept. of Oral Radiology, College of Dentistry, Seoul National University, Seoul (Korea, Republic of)

    1980-11-15

    The mandibular canal must be considered carefully during the surgical treatment, especially surgical extraction of the impacted tooth and intraosseous implant, because it contains the important inferior alveolar nerve and vessels. The author investigated the curvature of the mandibular canal and its relation to the mandibular molars and positional relation between the mental foramen and the mandibular premolars in orthopantomogram. The materials consisted of 441 orthopantomograms divided four groups; Group I consisted of 56 males and 44 females from 1 to 6 years of age, Group II consisted of 58 males and 45 females from 7 to 12 years of age, Group III consisted of 65 males and 33 females from 13 to 18 years of age, Group IV consisted of 86 males and 54 females over 19 years of age. The results were as followings; 1. The curvature of mandibular canal was 144.50 .deg. in Group II, 148.11 .deg. in Group III, 147.33 .deg. in Group IV. 2. The curvature of mandibular canal was located most frequently on the area between mandibular 1st molar and mandibular 2nd molar in Group I (42%) and on the mandibular 2nd molar area in Group II (54%), Group III (59%), Group IV (53%). 3. The position of mental foramen was most frequently below the mandibular 1st premolar in Group I (58%), between the mandibular 1st premolar and the 2nd premolar in Group II (62%), Group III (47%), and below the mandibular 2nd premolar in Group IV (58%).

  11. Lesions in the external auditory canal

    Directory of Open Access Journals (Sweden)

    Priyank S Chatra

    2011-01-01

    Full Text Available The external auditory canal is an S- shaped osseo-cartilaginous structure that extends from the auricle to the tympanic membrane. Congenital, inflammatory, neoplastic, and traumatic lesions can affect the EAC. High-resolution CT is well suited for the evaluation of the temporal bone, which has a complex anatomy with multiple small structures. In this study, we describe the various lesions affecting the EAC.

  12. Semiconductor laser irradiation improves root canal sealing during routine root canal therapy.

    Science.gov (United States)

    Su, Dandan; Hu, Xingxue; Wang, Dashan; Cui, Ting; Yao, Ruyong; Sun, Huibin

    2017-01-01

    To evaluate the effect of semiconductor laser irradiation on root canal sealing after routine root canal therapy (RCT). Sixty freshly extracted single-rooted human teeth were randomly divided into six groups (n = 10). The anatomic crowns were sectioned at the cementoenamel junction and the remaining roots were prepared endodontically with conventional RCT methods. Groups A and B were irradiated with semiconductor laser at 1W for 20 seconds; Groups C and D were ultrasonically rinsed for 60 seconds as positive control groups; Groups E and F without treatment of root canal prior to RCT as negative control groups. Root canal sealing of Groups A, C and E were evaluated by measurements of apical microleakage. The teeth from Groups B, D and F were sectioned, and the micro-structures were examined with scanning electron microscopy (SEM). One way ANOVA and LSD-t test were used for statistical analysis (α = .05). The apical sealing of both the laser irradiated group and the ultrasonic irrigated group were significantly different from the control group (p0.5). SEM observation showed that most of the dentinal tubules in the laser irradiation group melted, narrowed or closed, while most of the dentinal tubules in the ultrasonic irrigation group were filled with tooth paste. The application of semiconductor laser prior to root canal obturation increases the apical sealing of the roots treated.

  13. Semiconductor laser irradiation improves root canal sealing during routine root canal therapy.

    Directory of Open Access Journals (Sweden)

    Dandan Su

    Full Text Available To evaluate the effect of semiconductor laser irradiation on root canal sealing after routine root canal therapy (RCT.Sixty freshly extracted single-rooted human teeth were randomly divided into six groups (n = 10. The anatomic crowns were sectioned at the cementoenamel junction and the remaining roots were prepared endodontically with conventional RCT methods. Groups A and B were irradiated with semiconductor laser at 1W for 20 seconds; Groups C and D were ultrasonically rinsed for 60 seconds as positive control groups; Groups E and F without treatment of root canal prior to RCT as negative control groups. Root canal sealing of Groups A, C and E were evaluated by measurements of apical microleakage. The teeth from Groups B, D and F were sectioned, and the micro-structures were examined with scanning electron microscopy (SEM. One way ANOVA and LSD-t test were used for statistical analysis (α = .05.The apical sealing of both the laser irradiated group and the ultrasonic irrigated group were significantly different from the control group (p0.5. SEM observation showed that most of the dentinal tubules in the laser irradiation group melted, narrowed or closed, while most of the dentinal tubules in the ultrasonic irrigation group were filled with tooth paste.The application of semiconductor laser prior to root canal obturation increases the apical sealing of the roots treated.

  14. Comparison of Bacterial Leakage between 3 Different Root Canal Obturation Techniques in Oval Shaped Canals

    Directory of Open Access Journals (Sweden)

    Eshagh-ali Saberi

    2014-06-01

    Full Text Available Introduction: The purpose of this study was to evaluate the sealing ability of 3 obturation techniques in oval-shaped canals by bacterial leakage assessment. Methods: Sixty mandibular incisors with oval canals were selected after providing buccolingual and mesiodistal radiographs. The teeth were sectioned at a 10 mm distance from the apex. After instrumentation, the teeth were divided into 3 groups and the canals in the three groups were obturated with lateral condensation (G1, warm vertical condensation (G2 and thermoplasticized injectable gutta percha (G3. The teeth were exposed to human saliva. Observing the turbidity of the BHI broth for a period of 63 days the number of days required for the complete contamination of root canals was recorded. The data were analyzed using descriptive statistical methods and Kruskal-Wallis test with SPSS statistical software. Results: Warm vertical condensation (G2 needed a significantly greater average time for leakage than the two other methods. No significant differences were found between lateral condensations and thermoplasticized injectable G.P techniques. Conclusion: warm vertical condensation provides a better seal against bacterial leakage than lateral condensation and obtura II method in obturating oval-canals.

  15. Anterior canal lithiasis: diagnosis and treatment.

    Science.gov (United States)

    Casani, Augusto Pietro; Cerchiai, Niccolò; Dallan, Iacopo; Sellari-Franceschini, Stefano

    2011-03-01

    To describe the clinical and oculographic features in patients with anterior semicircular canal benign paroxysmal positional vertigo and to determine the efficacy of a canalith repositioning procedure for its management. Case series with chart review of patients presenting positional vertigo and positional downbeating nystagmus during a 2-year period. Outpatients' tertiary referral center for balance disorders. Eighteen patients suffering from positional vertigo and presenting positional downbeating nystagmus were treated with a maneuver based on a modification of the procedure proposed by Crevits. disappearance of positional downbeating nystagmus. Positional downbeating nystagmus was elicited unilaterally with the Dix-Hallpike maneuver in 6 cases. In 4 patients, it was triggered by both left and right Dix-Hallpike tests. In 8 patients, the positional nystagmus was elicited by a straight head-hanging maneuver. The positional nystagmus was purely downbeating in 12 patients. In the remaining, a torsional component was detected. After the treatment, only 1 patient showed positional nystagmus at 30 days. In anterior canal benign paroxysmal positional vertigo, the presence of a positional downbeating nystagmus in response to positional tests is key for diagnosis. In a significant number of patients, the affected side may not be detected because of the inconstant presence of a torsional component. Treatment with a simplified maneuver based on Crevits's technique can be considered an effective method for the treatment of anterior canal lithiasis, especially when the affected side cannot be detected clearly.

  16. Estimación de la madurez ósea en canales de bovino por fluorescencia diferencial

    Directory of Open Access Journals (Sweden)

    Gastón R. Torrescano Urrutia

    2012-01-01

    Full Text Available Actualmente, el análisis de clasificación de calidad de la canal depende en gran medida de la edad del animal; sin embargo, el patrón en México es demasiado impreciso, pues sólo requiere identificar si éste es menor o mayor a 30 meses. Esta falta de precisión genera la necesidad de sistemas objetivos para medir la madurez fisiológica. El propósito de esta investigación fue estimar de manera precisa el porcentaje de osificación del cartílago en la 12ava costilla, como un indicador de madurez ósea en canales de bovino, utilizando un esquema electrónico por visión artificial. En el esquema desarrollado se aprovecha la mayor fluorescencia que genera el cartílago, en comparación con la del hueso y la grasa, sobresaliendo claramente la región del cartílago, desarrollando algoritmos de procesamiento de imágenes para analizar esta región, y estimar de manera precisa el porcentaje de osificación, y por tanto la edad fisiológica de la canal. El sistema de visión artificial desarrollado permitió evaluar la madurez ósea de una canal en menos de un segundo, y la información obtenida fue utilizada para establecer la clasificación electrónica de la canal en menos de cinco segundos.

  17. Avaliação topográfica do canal mandibular por meio de radiografia panorâmica

    Directory of Open Access Journals (Sweden)

    Ingrid Macedo Oliveira

    2016-10-01

    Full Text Available O canal mandibular localiza-se no interior do corpo da mandíbula, podendo apresentar variações anatômicas. O conhecimento topográfico do canal mandibular por parte dos Cirurgiões-dentistas é de fundamental importância para obtenção de êxito em planejamentos cirúrgicos, anestesias e intervenções clínicas que envolvam a mandíbula. Estudar a anatomia do canal mandibular por meio de radiografias panorâmicas. Estudo descritivo retrospectivo, desenvolvido após análise e aprovação do Comitê de Ética e Pesquisa com o parecer de número 431.095. Foram analisadas 252 radiografias panorâmicas de pacientes dos gêneros masculino e feminino atendidos nas clínicas Odontológicas do Centro Universitário UNINOVAFAPI, Teresina-PI, Brasil. As radiografias foram analisadas com o auxílio de negatoscópio e cada antímero da mandíbula foi observado separadamente. Utilizou-se as classificações de Nortjé e de Langlais para descrição da topografia do canal mandibular. Análise estatística descritiva foi realizada com o programa SPSS versão 18.0. Observou-se uma prevalência de 38,89%, em ambos os antímeros, de canais mandibulares do Tipo II. O tipo IV esteve presente em 25,4% na hemiarcada direita e 26,6% na esquerda. Canal mandibular com bifurcação unilateral foi observado em 0,77% da amostra e canal reto molar não foi identificado. Observaram-se variações anatômicas, quanto ao número e trajeto do canal mandibular, com maior prevalência dos Tipos II e IV, e ausência de bifurcações. A radiografia panorâmica mostrou-se um recurso auxiliar importante na identificação do canal mandibular e suas variações.

  18. Environmental pollution and shipping feasibility of the Nicaragua Canal.

    Science.gov (United States)

    Chen, Jihong; Zeng, Xin; Deng, Yibing

    2016-12-15

    In recent years, the Nicaraguan government's renewed interest in constructing this interoceanic canal has once again aroused widespread concern, particularly in the global shipping industry. The project's immense ecological risks, coupled with the recent expansions of both the Panama Canal and the Suez Canal, have raised questions among scientists and experts about its viability. Whether the Nicaragua Canal is really feasible for international shipping, given its high marine pollution risks, requires the further study. This paper discusses and analyses the feasibility of the Nicaragua Canal in the context of its environmental impact and value as a shipping service. This paper aims to provide an important information reference to inform strategic decision-making among policymakers and stakeholders. Our research results indicate that the environmental complexity, economic costs and safety risks of building a new transoceanic canal are simply too high to justify the project. Copyright © 2016 Elsevier Ltd. All rights reserved.

  19. Root canal filling evaluation using optical coherence tomography

    Science.gov (United States)

    Negrutiu, Meda L.; Sinescu, Cosmin; Hughes, Michael; Bradu, Adrian; Todea, Carmen; Balabuc, Cosmin I.; Filip, Laura M.; Podoleanu, Adrian Gh.

    2008-04-01

    The root canal fillings are destined to seal the root canal especially in the apical areea. Invasive techniques are known which are used to assess the quality of the seal. These lead to the destruction of the probes and often no conclusion could be drawn in respect to the existence of any microleakage in the investigated areas of interest. Optical coherence tomography (OCT) is a relatively novel non-invasive imaging technique which presents potential in assessing the microleakage of the apical area in the root canal fillings with micron depth resolution. 3D reconstruction allows a complete view with obvious display of gaps in the apical root canal filling. For this study, 30 monoradicular teeth were prepared by conventional and rotative methods. Afterwards, root canal fillings were produced in each tooth. The images obtained show some microleakage in all the investigated root canal fillings. The advantages of the OCT method consist in non-invasiveness and high resolution.

  20. Canal of Nuck hernia: a multimodality imaging review

    Energy Technology Data Exchange (ETDEWEB)

    Rees, Mitchell A. [University of Pittsburgh Medical Center, Department of Radiology, Pittsburgh, PA (United States); Squires, James E. [Children' s Hospital of Pittsburgh of UPMC, Department of Gastroenterology, Pittsburgh, PA (United States); Tadros, Sameh; Squires, Judy H. [University of Pittsburgh Medical Center, Department of Radiology, Pittsburgh, PA (United States); Children' s Hospital of Pittsburgh of UPMC, Department of Radiology, Pittsburgh, PA (United States)

    2017-07-15

    Canal of Nuck abnormalities are a rare but important cause of morbidity in girls, most often those younger than 5 years of age. The canal of Nuck, which is the female equivalent of the male processus vaginalis, is a protrusion of parietal peritoneum that extends through the inguinal canal and terminates in the labia majora. The canal typically obliterates early in life, but in some cases the canal can partially or completely fail to close, potentially resulting in a hydrocele or hernia of pelvic contents. Recognition of this entity is especially important in cases of ovarian hernia due to the risk of incarceration and torsion. We aim to increase awareness of this condition by reviewing the embryology, anatomy and diagnosis of canal of Nuck disorders with imaging findings on US, CT and MRI using several cases from a single institution. (orig.)

  1. Single visit root canal treatment: A prospective study

    African Journals Online (AJOL)

    2013-08-31

    Aug 31, 2013 ... Post‑operative pain in multiple‑visit and single‑visit root canal treatment. J Endod 2010;36:36‑9. 13. Ferranti P. Treatment of the root canal of an infected tooth in one appointment: A report of 340 cases. Dent Dig 1959;65:49‑53. 14. Ufomata D. One‑visit root canal therapy: A preliminary clinical study in ...

  2. Three root canals in the maxillary second premolar

    Directory of Open Access Journals (Sweden)

    de Almeida-Gomes Fabio

    2009-01-01

    Full Text Available In this study, we report an endodontic treatment of the maxillary second premolar with three root canals and distinct foramens. The possibility of three root canals in this tooth is quite small; however, it must be taken into account in clinical and radiographic evaluation during endodontic treatment. Many times, their presence is noticed only after canal treatment due to continuing post-operative discomfort.

  3. Micro-Machined Flow Sensors Mimicking Lateral Line Canal Neuromasts

    OpenAIRE

    Hendrik Herzog; Siegfried Steltenkamp; Adrian Klein; Simon Tätzner; Elisabeth Schulze; Horst Bleckmann

    2015-01-01

    Fish sense water motions with their lateral line. The lateral line is a sensory system that contains up to several thousand mechanoreceptors, called neuromasts. Neuromasts occur freestanding on the skin and in subepidermal canals. We developed arrays of flow sensors based on lateral line canal neuromasts using a biomimetic approach. Each flow sensor was equipped with a PDMS (polydimethylsiloxane) lamella integrated into a canal system by means of thick- and thin-film technology. Our artificia...

  4. [Canal infection. Ecological theory and repair with osteodentin].

    Science.gov (United States)

    Muñiz, M A; Zeberio, T

    1991-01-01

    The characteristics of the infection in the root canal are analyzed, specially its development before pulpal necrosis. It is inferred that it is an ecological infection with a function: to decompose the necrosis. Inactivating the infection in the canal by the formocresol technique, calcium hidroxide or with the conventional basic treatment in Endodontics, cleaning, washing, disinfecting and, in this case, with partial obturation of the canal, it is possible to induce a reparation with osteodentine that can cover all the free extension of the canal.

  5. Mandibular second premolar with three canals: Re-treatment of a case with unusual root canal anatomy

    Directory of Open Access Journals (Sweden)

    Niranjan Desai

    2011-01-01

    Full Text Available A thorough knowledge of root canal anatomy along with the anatomical variations that may be present is essential for success of endodontic therapy. Unusual presentations in the number of the roots or the canals should be expected in every tooth. Mandibular second premolars are thought of as having a single root and canal. Studies have stated that the prevalence of three canals with three orifices in this tooth is 0.4%. The mandibular second premolar is particularly difficult to treat owing to the fact that a wide variation in the number, location and curvature of the roots and canals exist. Added to this is the fact that the access opening is restricted and location of the lingually placed orifices is difficult. This case report details the re-treatment of a mandibular second premolar with three canals and three separate orifices using the surgical microscope.

  6. Análisis de los cambios en los canales turísticos por la implantación de las TIC: una aproximación a la adopción del comercio móvil para la planificación de viajes

    OpenAIRE

    Vallespín Arán, María

    2014-01-01

    La revisión de la literatura nos ha permitido observar que, tras el proceso de maduración del comercio electrónico los investigadores y los gestores de empresas están prestando una gran atención a los dispositivos móviles. En este contexto, se estima que la incorporación del canal móvil al sistema de distribución de las empresas del sector turístico puede constituir una herramienta clave de diferenciación. Además, se observa una tendencia creciente a que los consumidores actúen a través de di...

  7. Análisis de los cambios en los canales turísticos por la implantación de las TIC: una aproximación a la adopción del comercio móvil para la planificación de viajes

    OpenAIRE

    Vallespín Arán, María

    2015-01-01

    La revisión de la literatura nos ha permitido observar que, tras el proceso de maduración del comercio electrónico los investigadores y los gestores de empresas están prestando una gran atención a los dispositivos móviles. En este contexto, se estima que la incorporación del canal móvil al sistema de distribución de las empresas del sector turístico puede constituir una herramienta clave de diferenciación. Además, se observa una tendencia creciente a que los consumidores actúen a través de di...

  8. Aplicação da modelagem por redes de Petri para avaliação ocupacional de trabalhadores

    Directory of Open Access Journals (Sweden)

    Jonas Lied

    2009-07-01

    Full Text Available Este trabalho introduz a modelagem por Redes de Petri Coloridas (RPC como ferramenta para avaliação dos riscos ocupacionais de trabalhadores em uma linha de manufatura. O uso da ferramenta consiste em modelar a linha de manufatura por Redes de Petri Coloridas, simular o modelo em computador, informando a situação inicial do processo.  A partir deste ponto, com os resultados obtidos da simulação avaliar a carga de trabalho individual dos trabalhadores, permitindo verificar quais as tarefas desenvolvidas devem ser estudadas para diminuição dos riscos ocupacionais envolvidos. Foi possível verificar que alguns trabalhadores estão sobrecarregados e outros folgados na linha de montagem estudada.

  9. La comunicación móvil como elemento innovador en el canal tradicional de tiendas de barrio

    Directory of Open Access Journals (Sweden)

    Bolaños López, Carlos Arturo

    2017-01-01

    Full Text Available La importancia que tienen las tiendas de barrio en la estructura de la economía del país es muy relevante y muchas personas viven de esta actividad. En el ámbito comercial, el canal Tienda a Tienda (TAT es el más antiguo y el menos tecnificado; pero aun así sigue siendo un canal de distribución muy importante para las grandes industrias. Sin embargo, con la llegada de grandes competidores nacionales e internacionales se ve amenazada la prosperidad de muchos tenderos y empresarios que viven en función de este canal. Por esto es muy importante prepararse con herramientas tecnológicas que sean funcionales y efectivas, como las aplicaciones móviles, que brindan información de gran utilidad al tendero sobre su negocio y su entorno. A su vez, estas herramientas tecnológicas pueden ser aprovechadas por las compañías proveedoras para brindar publicidad eficiente, con datos personalizados, así como realimentarse del servicio que están ofreciendo al mercado y tomar toda la información que requieran para sus estrategias corporativas. En la investigación, se aborda teóricamente el tema y se formula una estrategia que introduce elementos innovadores en la relación comercial del canal TAT mediante la implementación de una aplicación móvil para que el tendero conozca, en línea, el portafolio de servicios, precios sugeridos de venta y la forma ideal de exhibición, entre otros elementos, y que a la vez aporte a la productividad y eficiencia en el servicio de los proveedores.

  10. A Case of Recurrent Urticaria Due to Formaldehyde Release from Root-Canal Disinfectant.

    Science.gov (United States)

    Jang, Ji Hoon; Park, Seung Hyun; Jang, Hang Jea; Lee, Sung Geun; Park, Jin Han; Jeong, Jae Won; Park, Chan Sun

    2017-01-01

    Although formaldehyde is well known to cause type 4 hypersensitivity, immunoglobulin E (IgE)-mediated hypersensitivity to formaldehyde is rare. Here, we report a case of recurrent generalized urticaria after endodontic treatment using a para-formaldehyde (PFA)-containing root canal sealant and present a review of previous studies describing cases of immediate hypersensitivity reactions to formaldehyde. A 50-year-old man visited our allergy clinic for recurrent generalized urticaria several hours after endodontic treatment. Prick tests to latex, lidocaine, and formaldehyde showed negative reactions. However, swelling and redness at the prick site continued for several days. The level of formaldehyde-specific IgE was high (class 4). Thus, the patient was deemed to have experienced an IgE-mediated hypersensitivity reaction caused by the PFA used in the root canal disinfectant. Accordingly, we suggest that physicians should pay attention to type I hypersensitivity reactions to root canal disinfectants, even if the symptoms occur several hours after exposure.

  11. Anestesia en el Síndrome de Down con canal auricoloventricular común

    Directory of Open Access Journals (Sweden)

    Lincoln de la Parte Pérez

    1995-08-01

    Full Text Available Se realiza un estudio retrospectivo en 22 niños con síndrome de Down y canal auriculoventricular común, operados en el Cardiocentro del Hospital Pediátrico Docente "William Soler" durante el período 1986 a 1992. Dieciocho pacientes padecían de insuficientcia cardíaca (82 % y de éstos 16 (73 % de hipertensión pulmonar preoperatoria. Diez pacientes fallecieron en el posoperatorio para una mortalidad del 45 %.

  12. El comercio justo (ll). Canales de distribución, proceso comercial y tendencias

    OpenAIRE

    González Gascón, Elena; Juan Vigaray, María Dolores de; Kanther, Andreas

    2014-01-01

    El Comercio Justo hace referencia a un comercio más responsable, ético y sostenible para todos sus miembros, especialmente los productores en origen. Con este artículo se completa la serie sobre la tipología comercial de Comercio Justo ofreciendo una visión global de esta particular forma de Distribución y Consumo de productos "justos". En primer lugar se presenta la situación de los canales de distribución del Comercio Justo en España. Se profundiza en las funciones que se realizan a través ...

  13. Anestesia en el Síndrome de Down con canal auricoloventricular común

    OpenAIRE

    Lincoln de la Parte Pérez; Blas Hernández Suárez; Arístides Yanes Calderón; Maura Pérez Rivero

    1995-01-01

    Se realiza un estudio retrospectivo en 22 niños con síndrome de Down y canal auriculoventricular común, operados en el Cardiocentro del Hospital Pediátrico Docente "William Soler" durante el período 1986 a 1992. Dieciocho pacientes padecían de insuficientcia cardíaca (82 %) y de éstos 16 (73 %) de hipertensión pulmonar preoperatoria. Diez pacientes fallecieron en el posoperatorio para una mortalidad del 45 %.

  14. Three distal root canals in mandibular first molar with different canal configurations: Report of two cases and literature review

    Directory of Open Access Journals (Sweden)

    Parul Bansal

    2015-01-01

    Full Text Available With the increasing number of reports of aberrant root canal morphology, the clinician needs to be aware of the variable anatomy. Various case reports have been published with the finding of middle mesial canal in mandibular first molar, however finding of three distal canals in distal roots of mandibular first molar is rare. This article reports endodontic management of two mandibular first molars presented with three distal canals present in a single distal root (Sert and Bayirli type XVIII and distal and distolingual root.

  15. Water Environment Evolution along the China Grand Canal

    Science.gov (United States)

    Mao, F.; Wu, Y. X.; Yang, B. F.; Li, X. J.

    2014-03-01

    The China Grand Canal is one of the earliest canals in the world, having lasted for nearly 3000 years. Even its section canals have a rich history, such as the North-South Grand Canal that was established during the Sui Dynasty, whereas the Beijing-Hangzhou Canal was excavated during the Yuan Dynasty and the east line of the South-to-North Water Diversion. As one of the longest in the world, the China Grand Canal's total length is over 3500 kilometers. This length includes the navigable, unnavigable, and underground sections. Making the best use of situations and according to local conditions, the Chinese people harmoniously constructed the Beijing-Hangzhou Canal with nature. Tens of millions of workers took nearly 3000 years to complete the great shipping system. Navigable sections still exist for up to 900 kilometers and the volume of freight traffic is approximately 300 million tons. The canal remains the main logistical channel of the North-to-South Coal Transportation, South-to-North Water Diversion, and resources circulation. To date, China is promoting the success of heritage application. Part of these efforts is the declaration of the China Grand Canal as a World Cultural Heritage by 2014. In addition, the east route of the South-to-North Water Transfer project is planned to be navigable by 2016. The ancient Beijing-Hangzhou Grand Canal will usher in the new ecological civilization and cultural revival along the canal. This paper presents technical methods of water environment evolution research on the river system, river, and water quality along the Beijing-Hangzhou Canal through the integration of historical literature and modern remote sensing image data. The study carried out water environment investigation and analysis along the Beijing-Hangzhou canal by using ETM, SPOT image data, and GPS measurement data. Spatial and temporal evolution characteristics and regulations of the Beijing-Hangzhou Grand Canal regional water environment in the span of 3000

  16. Root canal treatment of mandibular second premolar tooth with taurodontism

    Directory of Open Access Journals (Sweden)

    Vujašković Mirjana

    2008-01-01

    Full Text Available INTRODUCTION Taurodontism is a morphoanatomical change in the shape of a tooth. An enlarged body of a tooth with smaller than usual roots is a characteristic feature. Internal tooth anatomy correlates with this appearance, which means that a taurodontal tooth has a large pulp chamber and apically positioned furcations. This dental anomaly may be associated with different syndromes and congenital discoders. CASE OUTLINE The case report presents the patient of a rare case of taurodontism in the mandibular second premolar with chronic periodontitis. Endodontic treatment was performed after dental history and clinical examination. Special care is required in all segments of endodontic treatment of a taurodontal tooth from the identification orifice, canal exploration, determining working length, cleaning and shaping and obturation of the root canal. Precurved K-file was used for canal exploration and location of the furcation. One mesial and one distal canal with the buccal position were identified in the apical third of the root canal. The working lengths of two canals were determined by radiographic interpretation with two K-files in each canal and verified with the apex locator. During canal instrumentation, the third canal was located in the disto-lingual position. The working length of the third canal was established using the apex locator. CONCLUSION Thorough knowledge of tooth anatomy and its variations can lead to lower percentage of endodontic failure. Each clinical case involving these teeth should be investigated carefully, clinically and radiographically to detect additional root canals. High quality radiographs from different angles and proper instrumentarium improve the quality of endodontic procedure.

  17. [Root canal treatment of mandibular second premolar tooth with taurodontism].

    Science.gov (United States)

    Vujasković, Mirjana; Karadzić, Branislav; Miletić, Vesna

    2008-01-01

    Taurodontism is a morphoanatomical change in the shape of a tooth. An enlarged body of a tooth with smaller than usual roots is a characteristic feature. Internal tooth anatomy correlates with this appearance, which means that a taurodontal tooth has a large pulp chamber and apically positioned furcations. This dental anomaly may be associated with different syndromes and congenital discoders. The case report presents the patient of a rare case of taurodontism in the mandibular second premolar with chronic periodontitis. Endodontic treatment was performed after dental history and clinical examination. Special care is required in all segments of endodontic treatment of a taurodontal tooth from the identification orifice, canal exploration, determining working length, cleaning and shaping and obturation of the root canal. Precurved K-file was used for canal exploration and location of the furcation. One mesial and one distal canal with the buccal position were identified in the apical third of the root canal. The working lengths of two canals were determined by radiographic interpretation with two K-files in each canal and verified with the apex locator. During canal instrumentation, the third canal was located in the disto-lingual position. The working length of the third canal was established using the apex locator. Thorough knowledge of tooth anatomy and its variations can lead to lower percentage of endodontic failure. Each clinical case involving these teeth should be investigated carefully, clinically and radiographically to detect additional root canals. High quality radiographs from different angles and proper instrumentarium improve the quality of endodontic procedure.

  18. File list: His.CDV.50.AllAg.Atrioventicular_canals [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available His.CDV.50.AllAg.Atrioventicular_canals mm9 Histone Cardiovascular Atrioventicular ...canals http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/His.CDV.50.AllAg.Atrioventicular_canals.bed ...

  19. File list: His.CDV.05.AllAg.Atrioventicular_canals [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available His.CDV.05.AllAg.Atrioventicular_canals mm9 Histone Cardiovascular Atrioventicular ...canals http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/His.CDV.05.AllAg.Atrioventicular_canals.bed ...

  20. File list: Unc.CDV.50.AllAg.Atrioventicular_canals [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Unc.CDV.50.AllAg.Atrioventicular_canals mm9 Unclassified Cardiovascular Atrioventic...ular canals http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/Unc.CDV.50.AllAg.Atrioventicular_canals.bed ...

  1. File list: Unc.CDV.05.AllAg.Atrioventicular_canals [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Unc.CDV.05.AllAg.Atrioventicular_canals mm9 Unclassified Cardiovascular Atrioventicular cana...ls http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/Unc.CDV.05.AllAg.Atrioventicular_canals.bed ...

  2. File list: His.CDV.20.AllAg.Atrioventicular_canals [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available His.CDV.20.AllAg.Atrioventicular_canals mm9 Histone Cardiovascular Atrioventicular cana...ls http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/His.CDV.20.AllAg.Atrioventicular_canals.bed ...

  3. File list: His.CDV.10.AllAg.Atrioventicular_canals [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available His.CDV.10.AllAg.Atrioventicular_canals mm9 Histone Cardiovascular Atrioventicular cana...ls http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/His.CDV.10.AllAg.Atrioventicular_canals.bed ...

  4. File list: Unc.CDV.20.AllAg.Atrioventicular_canals [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Unc.CDV.20.AllAg.Atrioventicular_canals mm9 Unclassified Cardiovascular Atrioventicular cana...ls http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/Unc.CDV.20.AllAg.Atrioventicular_canals.bed ...

  5. File list: Unc.CDV.10.AllAg.Atrioventicular_canals [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Unc.CDV.10.AllAg.Atrioventicular_canals mm9 Unclassified Cardiovascular Atrioventicular cana...ls http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/Unc.CDV.10.AllAg.Atrioventicular_canals.bed ...

  6. Mobile bot: Um chatterbot educacional para dispositivos móveis

    Directory of Open Access Journals (Sweden)

    Rony Marcolino Andrade

    2012-11-01

    Full Text Available Os programas que tentam simular diálogos com o ser humano recebem o nome de robôs de conversação ou chatterbots. Ao se utilizar os chatterbots na educação é possível relacionar os alunos e o computador através da linguagem natural, por sua vez o emprego dos chatterbots em dispositivos móveis possibilita a interação do aluno com um agente pedagógico disponível em qualquer lugar e qualquer momento. Nesse sentido, o objetivo desse trabalho é propor o desenvolvimento e avaliação do Mobile bot, um chatterbot educacional para uso em dispositivos móveis com conhecimentos sobre internet.

  7. Endodontic management of permanent mandibular left first molar with six root canals

    Directory of Open Access Journals (Sweden)

    Sachin Gupta

    2012-01-01

    Full Text Available The endodontic treatment of a mandibular molar with aberrant canal configuration can be diagnostically and clinically challenging. This case report presents the treatment of a mandibular first molar with six root canals, of which three canals were located in the mesial root and three in distal root. Third canals were found between the two main root canals. This case presents a rare anatomic configuration and points to the importance of expecting and searching for additional canals.

  8. Visibility of the central canal on MRI

    Energy Technology Data Exchange (ETDEWEB)

    Petit-Lacour, M.C.; Lasjaunias, P.; Iffenecker, C.; Benoudiba, F.; Hadj Rabia, M.; Doyon, D. [Service de Neuroradiologie, Faculte de Paris Sud (France); Hurth, M. [Department of Neurosurgery, Faculte Paris Sud, Kremlin-Bicetre (France)

    2000-10-01

    The central canal of the spinal cord is present at birth and becomes progressively obliterated. Cadaver studies have shown that it may persiste partially or completely. To our knowledge, this entity has not been described on MRI. We reviewed 794 MRI studies of the spinal cord, and found 12 patients (aged 14 to 65 years) who had an intramedullary cavity. The cavity was at the junction of the ventral {sup 1}/{sub 3} and dorsal {sup 2}/{sub 3} of the spinal cord, except at the level of the lumbar enlargement, where it was central. It was filiform in most cases, although sometimes fusiform (3 to 4 mm in diameter), and had regular contours. The cavity were thoracic in 69 % of cases. The clinical features were totally unrelated to the image, and there were no anatomical factors (Chiari malformation, dysraphism) predisposing to syringomyelia. The images were perfectly compatible with a persistent central canal, which we interpret as a variant of normal anatomy. Therefore it is important to regard these findings as normal, to avoid unnecessary treatment and follow-up. (orig.)

  9. Root canals-from concretion to patency

    Directory of Open Access Journals (Sweden)

    Chandrakar Chaman

    2015-01-01

    Full Text Available Teeth with calcification provide an endodontic treatment challenge; traumatized teeth usually develop partial or total pulpal obliteration which is characterized by apparent loss of the pulp space radiographically and a yellow discoloration of the clinical crown. Since only 7-27% of such teeth develop pulp necrosis with radiographic signs of apical periodontitis, it is difficult to decide whether to treat these teeth immediately upon detection of the pulpal obliteration or to wait until signs and symptoms of pulp and/or apical periodontitis occur. This article reviews the etiology, prevalence, classification, mechanism, diagnosis as well as treatment options for teeth with pulp obliteration and the various management approaches and treatment strategies for overcoming potential complications. A search of articles from "PubMed" and "Medline" from 1965 to present was done with the keywords dental trauma, discoloration, pathfinding instruments, pulp canal obliteration, and root canal treatment was conducted. A total of 94 abstracts were collected, of which 70 relevant articles were read and 31 most relevant articles were included in this article.

  10. Assessment of three root canal preparation techniques on root canal geometry using micro-computed tomography: In vitro study

    Directory of Open Access Journals (Sweden)

    Shaikha M Al-Ali

    2012-01-01

    Full Text Available Aim: To assess the effects of three root canal preparation techniques on canal volume and surface area using three-dimensionally reconstructed root canals in extracted human maxillary molars. Materials and Methods: Thirty extracted Human Maxillary Molars having three separate roots and similar root shape were randomly selected from a pool of extracted teeth for this study and stored in normal saline solution until used. A computed tomography scanner (Philips Brilliance CT 64-slice was used to analyze root canals in extracted maxillary molars. Specimens were scanned before and after canals were prepared using stainless steel K-Files, Ni-Ti rotary ProTaper and rotary SafeSiders instruments. Differences in dentin volume removed, the surface area, the proportion of unchanged area and canal transportation were calculated using specially developed software. Results: Instrumentation of canals increased volume and surface area. Statistical analysis found a statistically significant difference among the 3 groups in total change in volume (P = 0.001 and total change in surface area (P = 0.13. Significant differences were found when testing both groups with group III (SafeSiders. Significant differences in change of volume were noted when grouping was made with respect to canal type (in MB and DB (P < 0.05. Conclusion: The current study used computed tomography, an innovative and non destructive technique, to illustrate changes in canal geometry. Overall, there were few statistically significant differences between the three instrumentation techniques used. SafeSiders stainless steel 40/0.02 instruments exhibit a greater cutting efficiency on dentin than K-Files and ProTaper. CT is a new and valuable tool to study root canal geometry and changes after preparation in great details. Further studies with 3D-techniques are required to fully understand the biomechanical aspects of root canal preparation.

  11. Endodontic management of mandibular canine with two canals

    Directory of Open Access Journals (Sweden)

    Nidhi Shrivastava

    2013-01-01

    Full Text Available Endodontic treatment may sometimes fail because morphological features of the tooth adversely affect the treatment procedures. Many investigators have reported the anatomical variations associated with mandibular canines. Mandibular canines are recognized as usually having one root and one root canal in most cases. This case report describes a clinical case of mandibular canine with two canals. Human mandibular canines do not present internal anatomy as simple as could be expected; there are such canines with a single root and two canals, two roots or fused roots. The existence of mandibular canines with more than one root canal is a fact that clinicians ought to keep in mind, in order to avoid failure during endodontic treatment. In spite of the low incidence of lower canines with one root and two canals, this possibility cannot be forgotten, inasmuch as the presence of a second canal in these teeth leads to difficulties in endodontic treatment. The precise knowledge of the dental endocanalicular system′s anatomy is essential in the success of the root canal therapy, because the failure to detect the accessories canals and the incomplete radicular obturation leads to the infection of the periapical space, which will ultimately result in the loss of the tooth.

  12. Technical quality of root canal treatment in Taiwan.

    Science.gov (United States)

    Chueh, L-H; Chen, S-C; Lee, C-M; Hsu, Y-Y; Pai, S-F; Kuo, M-L; Chen, C-S; Duh, B-R; Yang, S-F; Tung, Y-L; Hsiao, Chuhsing Kate

    2003-06-01

    To evaluate the current technical quality of root canal treatment (RCT) in Taiwan. A total of 1085 RCT cases, randomly selected from a large sample and representative of the Taiwanese population from April to September 2000, were evaluated by eight endodontic specialists. The qualitative evaluation of RCT cases was based on two variables: length of the root filling and density of the obturation. A root canal with both adequate filling length (the apical termination of the root filling within 2 mm of the radiographic apex) and complete obturation (no lateral or apical canal lumen visible in the apical one-third of the root canal) was defined as having good-quality endodontic work (GQEW). A tooth was defined as having a GQEW when all its canals were categorized as GQEW. From a total of 1867 root canals, overfilling occurred in 235 (12.6%), adequate filling length in 1152 (61.7%), underfilling in 466 (25.0%) and no filling in 12 (0.6%). Of the 1867 root canals, 710 (38.0%) demonstrated complete obturation and 1157 (62%) demonstrated incomplete obturation. GQEW was found in 650 (34.8%) root canals and 329 (30.3%) teeth. The percentage of teeth with GQEW in hospital cases (38.1%) was significantly greater (P RCT in Taiwan were either of inadequate filling length or sealing density.

  13. Lateral line canal morphology and signal to noise ratio

    Science.gov (United States)

    Klein, Adrian; Herzog, Hendrik; Bleckmann, Horst

    2011-04-01

    The lateral line system of fish is important for many behaviors, including spatial orientation, prey detection, shoaling, intra specific communication and entraining. The smallest sensory unit of the lateral line is the neuromast that occurs free standing on the skin and in fluid filled canals. With aid of the lateral line fish perceive minute water motions. In their natural habitat fish are not only faced with biotic water motion but also with the abiotic fluctuations caused by various inanimate sources. The detection of meaningful signals is crucial for survival, and therefore animals should be able to separate meaningful signals from noise. Fishes live in various habitats (e.g. in still water or in running water). Therefore it is not surprising that the number and distribution of neuromasts as well as canal dimension, canal shape and canal branching patterns differ among fish species. We studied how lateral line canal parameters influence the filter properties of lateral line canals. To do so we exposed artificial lateral line canals, equipped with artificial neuromasts (sensors), to the vortex street shed by a submerged cylinder and to air bubble noise. We found that certain canal parameters significantly can enhance the signal to noise ratio.

  14. 33 CFR 117.769 - Black Rock Canal.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Black Rock Canal. 117.769 Section 117.769 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements New York § 117.769 Black Rock Canal. The draws of the...

  15. 33 CFR 117.159 - Grant Line Canal.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Grant Line Canal. 117.159 Section 117.159 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements California § 117.159 Grant Line Canal. The draw of the...

  16. Segmental carpal canal pressure in patients with carpal tunnel syndrome.

    Science.gov (United States)

    Ikeda, Kazuo; Osamura, Naoki; Tomita, Katsuro

    2006-01-01

    To clarify which part of the median nerve is the most compressed and to compare carpal canal pressure with the latency of the sensory nerve potential and the duration of symptoms. Fifteen patients with idiopathic carpal tunnel syndrome were studied using a pressure guidewire system to record canal pressure. The wire was introduced from the distal end of the carpal canal to 2 cm proximal to the distal wrist crease (DWC) and then retracted in 5-mm increments using an image intensifier to guide the progress. A nerve conduction study was performed, and all patients were asked how long the symptoms lasted. Carpal canal pressure was significantly higher 5 to 15 mm distal to the DWC. The most compressed point was 10 mm distal to the DWC, with a pressure of 44.9 +/- 26.4 mm Hg. The correlation coefficient between the highest canal pressure and the latency was 0.393 and between highest canal pressure and duration of symptoms was 0.402. Our study showed that the most compressed part of the median nerve in the carpal canal is 10 mm distal to the DWC. The carpal canal pressure was related to the latency and to the duration of symptoms.

  17. Sexual dimorphism in cervical vertebral canal measurements of ...

    African Journals Online (AJOL)

    Sexual dimorphism in cervical vertebral canal measurements of human foetuses. ... Anatomy Journal of Africa ... Cervical parts of vertebral canal in 30 normal human foetuses was exposed in coronal plane and were divided in groups 1 and 2 which correspond with 2nd and 3rd trimester of pregnancy respectively. Groups 1 ...

  18. Morphology of root canals in lower human premolars | Baroudi ...

    African Journals Online (AJOL)

    Background The knowledge of the root canal morphology and the possible anatomical variations of mandibular premolars are important for the successful endodontic treatment of such cases. The aim of this study was to investigate the presence of two or three root canals in extracted first and second mandibular premolars ...

  19. Reform in Indian canal irrigation: does technology matter?

    NARCIS (Netherlands)

    Narain, V.

    2008-01-01

    This paper examines the implications of technology - the design of canal irrigation for irrigation management reform. With reference to two different design systems in Indian irrigation - shejpali and warabandi - it shows that the potential for reform varies with the design of canal irrigation.

  20. Determinação do sexo em catfish de canal (Ictalurus punctatus utilizando endoscopia

    Directory of Open Access Journals (Sweden)

    Fernando Souza Mendonça De Lima

    2011-06-01

    Full Text Available A identificação precoce do sexo em peixes é um procedimento importante para o desenvolvimento de estratégias que facilitem o manejo no plantel de reprodutores. A endoscopia pode ser utilizada para essa identificação, embora em peixes seu uso ainda seja restrito. Diante disso, o objetivo deste trabalho foi validar o uso do endoscópio rígido via poro urogenital para determinação do sexo do catfish de canal (Ictalurus punctatus. O equipamento utilizado foi um endoscópio Multipurpose Rigid™ 30º com 2,7 mm de diâmetro e 18 cm de comprimento. Foram examinados 60 peixes com peso variando entre 86 e 1.032 gramas nos quais foi introduzido o endoscópio via poro genital e, logo em seguida, eutanaziados para confirmação do sexo. Amostras de tecido gonadal foram coletadas para avaliação histológica do estádio de maturação e confirmação do sexo. Os resultados mostraram que dos 60 peixes examinados, 57 tiveram confirmação positiva do sexo via endoscopia, o que corresponde a 95% da amostra. A utilização da endoscopia para determinação do sexo em I. punctatus via poro genital é viável.

  1. Canales iónicos TRP y DEG/ENAC en órganos sensitivos del pez cebra

    OpenAIRE

    Viña Fernández, Eliseo

    2016-01-01

    En los vertebrados la capacidad para detectar y discriminar entre estímulos del entorno, y del medio interno, se consigue gracias a órganos sensoriales y receptores sensitivos dispersos por todo el cuerpo que dependen de la activación de canales iónicos para transducir los estímulos específicos en señales eléctricas. El presente trabajo de tesis se inscribe en una línea de investigación desarrollada en el Grupo SINPOS del Departamento de Morfología y Biología Celular de la Universidad d...

  2. Traditional and contemporary techniques for optimizing root canal irrigation.

    Science.gov (United States)

    Holliday, Richard; Alani, Aws

    2014-01-01

    Canal irrigation during root canal treatment is an important component of chemo-mechanical debridement of the root canal system. Traditional syringe irrigation can be enhanced by activating the irrigant to provide superior cleaning properties. This activation can be achieved by simple modifications in current technique or by contemporary automated devices. Novel techniques are also being developed, such as the Self-adjusting File (Re-Dent-Nova, Ra'anana, Israel), Ozone (Healozone, Dental Ozone, London, UK), Photoactivated Disinfection and Ultraviolet Light Disinfection. This paper reviews the techniques available to enhance traditional syringe irrigation, contemporary irrigation devices and novel techniques, citing their evidence base, advantages and disadvantages. Recent advances in irrigation techniques and canal disinfection and debridement are relevant to practitioners carrying out root canal treatment.

  3. Hydrology and environmental aspects of Erie Canal (1817-99)

    Science.gov (United States)

    Langbein, Walter Basil

    1976-01-01

    As the first major water project in the United States, the old Erie Canal provides an example of the hydrological and environmental consequences of water development. The available record shows that the project aroused environmental fears that the canal might be impaired by the adverse hydrologic effects of land development induced by the canal. Water requirements proved greater than anticipated, and problems of floods and hydraulic inefficiencies beset navigation throughout its history. The Erie Canal proved the practicality of major hydraulic works to the extent that operations and maintenance could cope with the burdens of deficiencies in design. The weight of prior experience that upland streams, such as the Potomac and Mohawk Rivers, had proved unsatisfactory for dependable navigation, led to a decision to build an independent canal which freed the location from the constraints of river channels and made possible a cross-country water route directly to Lake Erie. The decision on dimensioning the canal prism--chiefly width and depth-involved balance between a fear of building too small and thus not achieving the economic potentials, and a fear of building too expensively. The constraints proved effective, and for the first part of its history the revenues collected were sufficient to repay all costs. So great was the economic advantage of the canal that the rising trend in traffic soon induced an enlargement of the canal cross section, based upon a new but riskier objective-build as large as the projected trend in toll revenues would finance. The increased revenues did not materialize. Water supplies were a primary concern for both the planners and the operators of the canal. Water required for lockage, although the most obvious to the planners, proved to be a relatively minor item compared with the amounts of water that were required to compensate for leakage through the bed and banks of the canal. Leakage amounted to about 8 inches of depth per day. The total

  4. VARIATION OF MAXILLARY FIRST PREMOLAR WITH THREE ROOT CANALS

    Directory of Open Access Journals (Sweden)

    Janet Kirilova

    2014-09-01

    Full Text Available Background: Successful endodontic treatment requires effective biomechanical preparation of the root canals and three-dimensional obturation of the root canal system. This can be achieved only by knowing and identifying the variations in the root canal system of the endodontically treated teeth. The Aim: The aim of this article is to present cases of endodontic treatment of maxillary first premolar with three root canals – different types. Material and Methods: Five clinical cases of successful endodontic treatment of patients with maxillary first premolar and three root canals are described. Result and Discussion: It is noted that good endodontic practice requires good knowledge of dental anatomy and possible variations, accurate X-ray images, as well as use of magnifying equipment. Conclusion: Knowledge of dental anatomy is fundamental for good endodontic practice.

  5. Contribución a la caracterización espacial de canales con sistemas MIMO-OFDM en la banda de 2,45 Ghz

    OpenAIRE

    Mora Cuevas, Jonathan

    2015-01-01

    La tecnología de múltiples antenas ha evolucionado para dar soporte a los actuales y futuros sistemas de comunicaciones inalámbricas en su afán por proporcionar la calidad de señal y las altas tasas de transmisión que demandan los nuevos servicios de voz, datos y multimedia. Sin embargo, es fundamental comprender las características espaciales del canal radio, ya que son las características del propio canal lo que limita en gran medida las prestaciones de los sistemas de comunicación actuales...

  6. Momento de inercia a la torsión de barras de perfil canal // Torsional inertia Moment for a profile bar channel

    Directory of Open Access Journals (Sweden)

    R. Rivero Galán

    1998-01-01

    Full Text Available En el presente trabajo se brindan fórmulas y coeficientes para la determinación del momento de inercia a la torsión de una barrade perfil canal. Las fórmulas obtenidas se validan mediante la simulación de diferentes estructuras de uniones entre canales conel uso del método de los elementos finitos._______________________________________________________________________AbstractIn the paper are offered formulations and coefficients for the determination of the moment of inertia to the twist for a profilebar channel. The obtained formulations are validated through the simulation by the finite elements method of differentstructures of unions between channels.

  7. Superior Canal Dehiscence Syndrome Affecting 3 Families.

    Science.gov (United States)

    Heidenreich, Katherine D; Kileny, Paul R; Ahmed, Sameer; El-Kashlan, Hussam K; Melendez, Tori L; Basura, Gregory J; Lesperance, Marci M

    2017-07-01

    Superior canal dehiscence syndrome (SCDS) is an increasingly recognized cause of hearing loss and vestibular symptoms, but the etiology of this condition remains unknown. To describe 7 cases of SCDS across 3 families. This retrospective case series included 7 patients from 3 different families treated at a neurotology clinic at a tertiary academic medical center from 2010 to 2014. Patients were referred by other otolaryngologists or were self-referred. Each patient demonstrated unilateral or bilateral SCDS or near dehiscence. Clinical evaluation involved body mass index calculation, audiometry, cervical vestibular evoked myogenic potential testing, electrocochleography, and multiplanar computed tomographic (CT) scan of the temporal bones. Zygosity testing was performed on twin siblings. The diagnosis of SCDS was made if bone was absent over the superior semicircular canal on 2 consecutive CT images, in addition to 1 physiologic sign consistent with labyrinthine dehiscence. Near dehiscence was defined as absent bone on only 1 CT image but with symptoms and at least 1 physiologic sign of labyrinthine dehiscence. A total of 7 patients (5 female and 2 male; age range, 8-49 years) from 3 families underwent evaluation. Family A consisted of 3 adult first-degree relatives, of whom 2 were diagnosed with SCDS and 1 with near dehiscence. Family B included a mother and her child, both of whom were diagnosed with unilateral SCDS. Family C consisted of adult monozygotic twins, each of whom was diagnosed with unilateral SCDS. For all cases, dehiscence was located at the arcuate eminence. Obesity alone did not explain the occurrence of SCDS because 5 of the 7 cases had a body mass index (calculated as weight in kilograms divided by height in meters squared) less than 30.0. Superior canal dehiscence syndrome is a rare, often unrecognized condition. This report of 3 multiplex families with SCDS provides evidence in support of a potential genetic contribution to the etiology

  8. [The effect of left bacteria in the root canal on prognosis of the root canal therapy].

    Science.gov (United States)

    He, Jin-mei; Bian, Zhuan; Fan, Ming-wen; Fan, Bing

    2004-06-01

    To study the effect of the left bacteria on the root canal therapy. 50 single-rooted teeth with chronic apical periodontitis were divided into two groups, one was instrumented with step-back technique and 2.5%NaOCl ultrasonic irrigation for 3 min, then filled with Thermafil. Samples were taken after instrumentation to culture. The other was treated with traditional RCT at three visits. In 24 months the apical radiolucency were greatly reduced in all cases. There weren't significant relationship among the postoperative pain and the left bacteria, the degree of the obturation or the pre-operative symptoms (P > 0.05). The effect of left bacteria in root canal filled with Thermafil wasn't observed.

  9. Radiographic prevalence of root canal ramifications in a sample of root canal treatments in a Brazilian Dental School Prevalência radiográfica de ramificações do canal radicular em uma amostra de tratamentos endodônticos em uma Faculdade de Odontologia Brasileira

    Directory of Open Access Journals (Sweden)

    Iadasa de Quadros

    2007-06-01

    2000. Foram avaliadas as radiografias feitas durante o tratamento para verificar a presença das ramificações dos sistemas de canais radiculares. A radiografia inicial não mostrou a presença de qualquer ramificação. Depois da obturação as radiografias mostraram apenas 3 tipos de ramificação: 3,06% de canais laterais, 2,99% de deltas apicais e 0,1% de canais interradiculares. Os pré-molares superiores mostraram o maior número de canais laterais (n = 13, seguidos pelos pré-molares inferiores (n = 10 e incisivos superiores (n = 10. Deltas apicais foram encontrados principalmente em molares inferiores (n = 14, seguidos por incisivos superiores (n = 9. Apenas molares inferiores apresentaram canais interradiculares. A detecção de ramificações aumentou com o uso do EDTA. Entretanto, nenhuma relação estatisticamente significante foi encontrada entre o tipo de substância química auxiliar usada e o número de ramificações visualizadas após a obturação dos canais radiculares. Foi concluído que a freqüência de ramificações do canal radicular encontrada radiograficamente é baixa em tratamentos executados por estudantes universitários.

  10. Closing a chapter on Love Canal

    Energy Technology Data Exchange (ETDEWEB)

    1987-11-01

    The toxic wastes that were dumped in the 1950s at Love Canal in New York and then seeped into groundwater and the basements of local residents in the late 1970s are to be finally incinerated, according to a plan recently announced by the US Environmental Protection Agency (EPA). This last, five-year stage in the cleanup will entail the building of an incinerator for burning 35,000 cubic yards of dioxin-contaminated sediment dredged from creeks and sewers in the area at a cost of up to $31 million. The incinerated residue - which will be purified of detectable levels of dioxin, says EPA - will be returned to the site and spread several feet deep.

  11. 8. Le TGV et le canal

    OpenAIRE

    Fortier, Agnès

    2013-01-01

    7. Le TGV près du Creusot Une double rame du tgv Sud-Est se dirige vers Paris. Elle vient de franchir le viaduc du canal du Centre qui longe l’un de ses réservoirs d’alimentation, l’étang de Longpendu, visible sur la droite. Elle croise la voie « plm » dont on note le discret ballast en avant de l’étang. Plusieurs lignes à très haute tension partent d’un important équipement de répartition tout proche. L’une d’elles sert notamment à l’alimentation du tgv. La photographie est prise d’un des ra...

  12. Seismically observed seiching in the Panama Canal

    Science.gov (United States)

    McNamara, D.E.; Ringler, A.T.; Hutt, C.R.; Gee, L.S.

    2011-01-01

    A large portion of the seismic noise spectrum is dominated by water wave energy coupled into the solid Earth. Distinct mechanisms of water wave induced ground motions are distinguished by their spectral content. For example, cultural noise is generally Panama Canal there is an additional source of long-period noise generated by standing water waves, seiches, induced by disturbances such as passing ships and wind pressure. We compare seismic waveforms to water level records and relate these observations to changes in local tilt and gravity due to an oscillating seiche. The methods and observations discussed in this paper provide a first step toward quantifying the impact of water inundation as recorded by seismometers. This type of quantified understanding of water inundation will help in future estimates of similar phenomena such as the seismic observations of tsunami impact. Copyright 2011 by the American Geophysical Union.

  13. MANAGEMENT OF LUMBAR SPINAL CANAL STENOSIS

    Directory of Open Access Journals (Sweden)

    Mukhergee G. S

    2016-06-01

    Full Text Available BACKGROUND Spinal stenosis is one of the most common conditions in the elderly. It is defined as a narrowing of the spinal canal. The term stenosis is derived from the Greek word for narrow, which is “Stenos”. The first description of this condition is attributed to Antoine portal in 1803. Verbiest is credited with coining the term spinal stenosis and the associated narrowing of the spinal canal as its potential cause. [1-10] Kirkaldy–Willis subsequently described the degenerative cascade in the lumbar spine as the cause for the altered anatomy and pathophysiology in spinal stenosis. [11-15] If compression does not occur, the canal should be described as narrow but not stenotic. Some studies defined lumbar spinal stenosis as a “narrowing of the osteoligamentous vertebral canal and/or the intervertebral foramina causing compression of the thecal sac and/or the caudal nerve roots; at a single vertebral level, narrowing may affect the whole canal or part of it” (Postacchini 1983. This definition distinguished between disc herniation and stenosis. [16] . The most common type of spinal stenosis is caused by degenerative arthritis of the spine. Hypertrophy and ossification of the posterior longitudinal ligament which usually are confined to the cervical spine, and diffuse idiopathic skeletal hyperostosis (DISH syndrome also may result in an acquired form of spinal stenosis. Congenital forms caused by disorders such as achondroplasia and dysplastic spondylolisthesis are much less common. Congenital spinal stenosis usually is central and is evident or imaging studies. Idiopathic congenital narrowing usually involves the anteroposterior dimension of the canal secondary to short pedicles; the patient otherwise is normal. In contrast, in achondroplasia, the canal is narrowed in the anteroposterior plane owing to shortened pedicles and in lateral dimension because of diminished interpedicular distance. Acquired forms of spinal stenosis usually are

  14. Uso de un modelo de aguas someras para analizar la influencia del Atlántico Tropical Norte y del Pacífico Ecuatorial del Este sobre la circulación atmosférica en los mares Intra-Americanos

    OpenAIRE

    Eric J. Alfaro; Daniel Hernández; Arnoldo Bezanilla

    2007-01-01

    Se usó un modelo numérico de aguas someras para simular la circulación anómala en la región de los Mares Intra-Americanos (MIA) inducida por dos funciones forzantes asociadas con fuentes de calor localizadas en las regiones oceánicas del Atlántico Tropical Norte y del Pacífico Ecuatorial del Este, respectivamente. A pesar de su simplicidad, el modelo de aguas someras representó algunas de las características principales de la circulación inducida sobre los MIA por las funciones forzantes desc...

  15. [Latest treatment of lumbar canal stenosis].

    Science.gov (United States)

    Kim, Kyongsong; Isu, Toyohiko

    2009-06-01

    Lumbar canal stenosis (LCS) is a degenerative disease involving the lumbar vertebrae, discs, and ligamentum flavum that result in neurological deficit to some extent. The natural history of symptoms of LCS is highly important because they do not necessarily worsen with progressive degeneration. Therefore, a observation therapy is adopted for the treatment of this condition. Although invasive treatment is required for some patients, surgery cannot be performed solely on the basis of radiological findings and careful evaluation of neurological symptoms is necessary. In the event that spinal surgery is required, it is important to minimize degree of invasiveness; various devices and operative approaches and methods have been developed to this end. Our strategy for the surgical treatment of LCS involves microscopic decompression via a posterior approach. In our method, modified bilateral decompression via the splitting of the spinous process using an ultrasonic bone curette (SONOPET), and the results of this approach have been excellent. Our method is less invasive, facilitates the preservation of the paraspinal muscle, and represents a useful approach to posterior spinal elements. Our findings indicate that this method involves less muscle damage as compared to other methods. LCS should be differentiated from conditions other than those involving the spinal canal such as foraminal stenosis and far-out syndrome, piriformis syndrome, and tarsal tunnel syndrome. The incidence of these conditions is higher than appreciated and they present with neurological deficits similar to observed in LCS. Here, we report our criteria of operative indications for surger and the procedures that we developed for the treatment of LCS, based on a review of the available literature.

  16. Tumor borderline do ovário localizado no canal inguinal: relato de caso A borderline ovarian tumor in inguinal canal: case report

    Directory of Open Access Journals (Sweden)

    Vinícius Basso Preti

    2010-06-01

    Full Text Available Os sintomas do tumor ovariano são inespecíficos e uma forma rara de apresentação é como conteúdo de uma hérnia inguinal. Relatamos o caso de uma paciente de 82 anos, com diagnóstico de câncer de mama e lesão anexial hipoecoica à ecografia. A mesma foi submetida à cirurgia conservadora da mama e à laparotomia, com achado de lesão ovariana sólido-cística no interior do canal inguinal à direita. A análise por congelação foi negativa para malignidade, e o exame anatomopatológico mostrou tratar-se de tumor ovariano borderline.The symptoms of ovarian tumor are not specific and a rare presentation of the tumor is as the content of an inguinal hernia. We reported a case of an 82-year-old woman, diagnosed with breast cancer and with a concomitant hypoecoic adnexal mass at the ecographic exam. The patient was treated with conservative breast surgery and laparotomy. A cystic-solid ovarian lesion was found inside the right inguinal canal. Frozen-section examination was negative for malignancy, and the anatomopathological analysis revealed a borderline ovarian tumor.

  17. Comparison of two canal preparation techniques using mtwo rotary instruments.

    Science.gov (United States)

    Hamze, Faeze; Honardar, Kiamars; Nazarimoghadam, Kiumars

    2011-01-01

    Root canal preparation is an important process in endodontic therapy. Nickel-titanium (NiTi) rotary file system can be used in single length technique (simultaneous technique) without early coronal enlargement, as well as in crown-down method. The purpose of this in vitro study was to compare single length with crown-down methods' shaping ability using Mtwo NiTi files. Fifteen acrylic-resin blocks containing simulated canals were divided into two experimental groups. In group A, single length technique was used and in group B root canals were prepared by crown-down technique. Pre- and post-preparation canals were photographed in a standardized manner and were superimposed. The inner and outer walls of canal curvature were evaluated at three points (apical, middle and coronal) to determine the greatest change. The data was statistically analyzed using the Student t-test by Statistical Analysis System (SAS) software. Statistical analysis revealed that in group B, dentine was equally removed within the canal coronal to the curvature, whereas in group A, the inner wall was predominantly removed (Plength method and crown-down technique using Mtwo for preparation of apical and middle portion of canal curvature.

  18. Laser scanning dental probe for endodontic root canal treatment

    Science.gov (United States)

    Blank, Molly A. B.; Friedrich, Michal; Hamilton, Jeffrey D.; Lee, Peggy; Berg, Joel; Seibel, Eric J.

    2011-03-01

    Complications that arise during endodontic procedures pose serious threats to the long-term integrity and health of the tooth. Potential complexities of root canals include residual pulpal tissue, cracks, mesial-buccal 2 and accessory canals. In the case of a failed root canal, a successful apicoectomy can be jeopardized by isthmuses, accessory canals, and root microfracture. Confirming diagnosis using a small imaging probe would allow proper treatment and prevent retreatment of endodontic procedures. An ultrathin and flexible laser scanning endoscope of 1.2 to 1.6mm outer diameter was used in vitro to image extracted teeth with varied root configurations. Teeth were opened using a conventional bur and high speed drill. Imaging within the opened access cavity clarified the location of the roots where canal filing would initiate. Although radiographs are commonly used to determine the root canal size, position, and shape, the limited 2D image perspective leaves ambiguity that could be clarified if used in conjunction with a direct visual imaging tool. Direct visualization may avoid difficulties in locating the root canal and reduce the number of radiographs needed. A transillumination imaging device with the separated illumination and light collection functions rendered cracks visible in the prepared teeth that were otherwise indiscernible using reflected visible light. Our work demonstrates that a small diameter endoscope with high spatial resolution may significantly increase the efficiency and success of endodontic procedures.

  19. Management of middle mesial canal in mandibular second molar

    Directory of Open Access Journals (Sweden)

    J V Karunakaran

    2012-01-01

    Full Text Available The primary objective of endodontic therapy is to achieve a three-dimensional obturation of the root canal space after adequate preparation of the canal space to remove the tissue debris, microorganisms, and their byproducts. Anatomical variations have frequently been encountered in endodontic practice and have to be adequately managed by the clinician. Missed roots and canals are a major reason for failure of therapy. Technological advances have given the clinician ample opportunity to identify and treat these aberrations successfully. The present report describes a left mandibular second permanent molar requiring root canal treatment, found to have three separate canals in the mesial root. This case demonstrates a rare anatomical configuration and emphasizes the need for the clinician to be aware of and look out for such variations and use adequate diagnostic methodologies prior to and during therapy to detect such variations. The possibility of additional canals, whenever in doubt, should be explored with the assistance of technologies such as those of magnification and illumination and various diagnostic aids. Operator experience has also shown to be a key factor in negotiation and management of these aberrant canal configurations.

  20. Variations in the Anatomical Structures of the Guyon Canal.

    Science.gov (United States)

    Fadel, Zahir T; Samargandi, Osama A; Tang, David T

    2017-05-01

    Compression neuropathy of the ulnar nerve at the Guyon canal is commonly seen by hand surgeons. Different anatomical variations of structures related to the Guyon canal have been reported in the literature. A thorough knowledge of the normal contents and possible variations is essential during surgery and exploration. To review the recognized anatomical variations within and around the Guyon canal. This study is a narrative review in which relevant papers, clinical studies, and anatomical studies were selected by searching electronic databases (PubMed and EMBASE). Extensive manual review of references of the included studies was performed. We also describe a case report of an aberrant muscle crossing the Guyon canal. This study identified several variations in the anatomical structures of the Guyon canal reported in the literature. Variations of the ulnar nerve involved its course, branching pattern, deep motor branch, superficial sensory branch, dorsal cutaneous branch, and the communication with the median nerve. Ulnar artery variations involved its course, branching pattern, the superficial ulnar artery, and the dorsal perforating artery. Aberrant muscles crossing the Guyon canal were found to originate from the antebrachial fascia, pisiform bone, flexor retinaculum, the tendon of palmaris longus, flexor carpi ulnaris, or flexor carpi radialis; these muscles usually fuse with the hypothenar group. The diverse variations of the contents of the Guyon canal were adequately described in the literature. Taking these variations into consideration is important in preventing clinical misinterpretation and avoiding potential surgical complications.

  1. Modeling and measurement of root canal using stereo digital radiography

    Science.gov (United States)

    Analoui, Mostafa; Krisnamurthy, Satthya; Brown, Cecil

    2000-04-01

    Determining root canal length is a crucial step in success of root canal treatment. Root canal length is commonly estimated based on pre-operation intraoral radiography. 2D depiction of a 3D object is the primary source of error in this approach. Techniques based on impedance measurement are more accurate than radiographic approaches, but do not offer a method for depicting the shape of canal. In this study, we investigated a stererotactic approach for modeling and measurement of root canal of human dentition. A weakly perspective model approximated the projectional geometry. A series of computer-simulated objects was used to test accuracy of this model as the first step. The, to assess the clinical viability of such an approach, endodontic files inserted in the root canal phantoms were fixed on an adjustable platform between a radiographic cone and an image receptor. Parameters of projection matrix were computed based on the relative positions of image receptors, focal spot, and test objects. Rotating the specimen platform from 0 to 980 degrees at 5-degree intervals set relative angulations for stereo images. Root canal is defined as the intersection of two surfaces defined by each projection. Computation of error for length measurement indicates that for angulations greater than 40 degrees the error is within clinically acceptable ranges.

  2. Antibacterial activity of different root canal sealers against Enterococcus faecalis

    Science.gov (United States)

    Trovati, Federico; Ceci, Matteo; Colombo, Marco; Pietrocola, Giampiero

    2017-01-01

    Background The aim of the present study was to compare in vitro the antimicrobial activity of different root canal sealers against Enterococcus faecalis, prior and subsequent to setting. Material and Methods Agar diffusion test (ADT) was used for evaluating the antibacterial activity of non-set sealer while the direct contact test (DCT) was used for after setting. Results ADT: Except for TotalFill BC Sealer all the others sealers tested showed antibacterial activity. BioRoot™RCS, MTA Fillapex and Sealapex Root Canal Sealer showed the lowest antibacterial activity, a significant increase in antibacterial effect for both Pulp Canal Sealer™ and AH plus sealers were found. Significantly higher were the mean diameters of the bacterial inhibition zone by both EasySeal or N2 sealers. DCT: AH plus and Sealapex Root Canal Sealer doesn’t show any bactericidal effect after 6 min of contact. After 15 and 60 min of contact a significant increment for AH plus and for Sealapex Root Canal Sealer of the bactericidal effect was found. Significantly much higher was the antibacterial effect of Sealapex Root Canal Sealer compare to that observed for AH plus. BioRootTMRCS, MTA Fillapex, Pulp Canal Sealer™ and N2 showed at least means of the number of colonies formed in milliliter after 6 min of contact. Except for N2, a significant increase in bactericidal effect after 15 and 60 min for the other compared sealers (BioRootTMRCS, MTA Fillapex and Pulp Canal Sealer™). Conclusions For every contact times considered, both TotalFill BC Sealer and EasySeal were bactericidal against E. faecalis and killed all bacteria. Key words:Agar diffusion test, antibacterial activity, direct contact test, Enterococcus faecalis, root canal sealer. PMID:28638549

  3. Evaluación de la calidad microbiológica de canales de pollo sacrificadas en el estado de Zulia (Venezuela). Aplicación de la normativa vigente

    OpenAIRE

    Luque-Moreno, Inmaculada; Molero, G; Huerta Lorenzo, Belén; Gómez-Gascón, Lidia; Cardoso-Toset, Fernando; Montiel, M.; Tarradas-Iglesias, Carmen

    2012-01-01

    En este trabajo se ha realizado un estudio para evaluar la calidad y seguridad microbiológica de canales de pollo envasadas en cinco mataderos de pollos ubicados en los municipios San Francisco, Maracaibo y Mara, del estado de Zulia, Venezuela (plantas A, B, C, D y E), para determinar la presencia de Salmonella spp. y el recuento de aerobios mesófilos, basándonos en legislación vigente (Norma Venezolana Covenin 2343-86 pollo beneficiado). Se han analizado 30 muestras de canales...

  4. Comparison of stresses induced by fiber post, parapost and casting post in root canals by photoelasticity method.

    Science.gov (United States)

    Rezaei, Aliakbar; Soltani, Fereidoon; Vafaei, Fariborz; Khoshhal, Masoumeh; Ayatollahi, Majid Reza; Soltani, Naser; Nejati, Morteza

    2010-01-01

    Many studies have been performed to evaluate the stress distribution around endodontic posts; those which compared posts composed of different materials are rare. The aim of this study was to compare stresses induced in dentin by three structurally different posts using photoelasticity method. Nine blocks of PSM-5 Photoelastic material with 45×45×10 mm dimension were prepared. In each block, a canal 9 mm in length and 0.8 mm in width was drilled. Blocks were divided into 3 groups of three each. In the first group, the canals were prepared for insertion of Fiber Post with 1.25 mm width. In the second group, the canals were prepared for insertion of ParaPost with 1.25 mm width and the canals in the third group were prepared for casting post similar to the above samples. Casting Post pattern was made by Duralay resin and casted by Ni-Cr alloy. All posts were cemented in canals with Panavia cement. The stresses were evaluated in the polariscope under three different conditions: 1) without load, 2) with 135 N vertical load, and 3) with 90 N oblique load (26° inclination to post long axis). The fringe orders in the cervical, middle and apical regions of the posts were evaluated and compared with each other. Application of the vertical load induced a high stress concentration (FO=4) in the apical region of the ParaPost, while lower stress was observed in the middle (FO=2) and cervical region (FO=2+). Fiber Post and Casting Post showed even stress distribution (FO=2+). High stress concentration was detected with the application of oblique force in the cervical region of ParaPost (FO=5) and Casting Post (FO=3+). Fiber Posts fractured before reaching 90-N loading force. The stress distribution around Fiber Post and Casting Post were constant in comparison with ParaPost. Fiber Post with 1.25 mm width was not recommended in situations with high oblique stresses.

  5. [Effect of quality of root canal obturation on the long-term results of root canal therapy].

    Science.gov (United States)

    Zhu, Ya-ping; Zhu, Ya-qin; Fan, Lin-feng; DU, Rong; Gu, Ying-xin; Qin, Feng

    2007-06-01

    The purpose of this study was to analyze the quality of obturation affecting the long-term results of root canal therapy (RCT) by radiographic evaluation. Teeth of RCT for 2 or more than 2 years were chosen, and periapical radiographs were taken with paralleling technique. The patients' age, gender, etiology, the time of therapy were recorded. The current apical periodontal status of these endodontically treated teeth were examined and recorded. The data were subjected to univariate and multivariate analysis with SPSS13.0 software package. This study investigated 215 cases with 376 endodontically treated teeth. The success rate was 54.79%. If counted by root canal, there were 513 root canals, the success rate was 61.4%. The quality of obturation including obturation position and obturation density affected significantly the results of root canal therapy (Pobturation position for successful treated canals was 0.5-2mm from the radiographic apex. The success rate was higher for a good obturation density, especially in the apical third. No statistically significant differences were found based on gender, age and obturation time. The quality of root canal obturation significantly affected the long-term results of root canal therapy.

  6. A scanning electron microscopy evaluation of the cleanliness of un-instrumented areas of canal walls after root canal preparation

    Directory of Open Access Journals (Sweden)

    Abdullah J Dohaithem

    2015-01-01

    Full Text Available Introduction: Cleanliness of the canal space is the ultimate goal of its preparation. Nevertheless, some portion of the canal walls are left un-instrumented during preparation. Therefore, the aim of this ex vivo study was to evaluate the cleanliness of un-instrumented canal walls after root canal preparation for the presence or absence of debris and smear layer. Materials and Methods: A total of 24 single-rooted extracted teeth were prepared with the crown-down technique using Protaper universal rotary file system. Micro-computed tomography (micro-CT was used to scan the specimens before and after instrumentation. The un-instrumented area was measured and localized. The roots were split longitudinally and then subjected to scanning electron microscopy (SEM. The presence of debris and smear layer in the instrumented and un-instrumented areas of the canal were evaluated by analysing the SEM images with a five-score evaluation system based on the reference photographs. Results: High levels of root canal cleanliness (≤ score 2 were found for the instrumented areas were detected (P = 0.003. Conclusions: Under the condition of this study, un-instrumented areas of the canal were less clean in comparison to instrumented portion.

  7. Sistema difuso para la detección automática de estilos de aprendizaje en ambientes de formación web

    Directory of Open Access Journals (Sweden)

    Miguel Ángel Palomino Hawasly

    2016-01-01

    Full Text Available Este trabajo presenta un sistema difuso que permite detectar estilos de aprendizaje para un entorno formativo personalizado orientado a la web, donde las características individuales de aprendizaje, se convierten en el insumo principal de estos escenarios innovadores de formación. Se presentan tres factores que se tuvieron en cuenta al momento de formalizar las distintas variables difusas: una adaptación del Test de Felder y Silverman, la ruta o traza de aprendizaje y una prueba de conocimientos, se describe la naturaleza y respectiva connotación de cada una de ellas, al igual que los criterios para la construcción de las reglas difusas, además se exponen algunos de los resultados obtenidos al momento de simular con diversos datos de entrada.

  8. Sistema de suporte a decisão para alocação de água em projetos de irrigação.

    OpenAIRE

    Mirléia Aparecida de Carvalho

    2003-01-01

    No presente trabalho, fez-se a adaptação do reservatório superficial do ModSimLS para trabalhar como reservatório do solo. O modelo denomina-se IrrigaLS. Por comparação com o método do balanço hídrico, verificou-se que o IrrigaLS é apto para determinar demandas de irrigação suplementares e/ou totais. Com a adaptação, o modelo considera a produção agrícola como o resultado da interação dos fatores água-clima-planta-solo. A capacidade de simular sistemas complexos de recursos hídricos foi testa...

  9. Un sistema presión-volumen para la medición de propiedades mecánicas de vasos cardíacos menores

    Directory of Open Access Journals (Sweden)

    Javier Navarro Rueda

    2013-04-01

    Full Text Available Las propiedades mecánicas de vasos cardíacos menores (VM son poco estudiadas. El sistema Presión-Volumen (PV propuesto, desarrollado para evaluar comportamientos esfuerzo-deformación (σ-ε de VM, permite variar controladamente la presión interna y simular alteraciones geométricas al tubo. Se obtuvieron imágenes de las geometrías para cada valor de presión interna. Asumiendo el tubo en equilibrio, con pared elástica y presiones conocidas, se determinaron esfuerzo y deformación circunferenciales. Se obtuvieron curvas σ-ε, validadas con ensayos de tensión uniaxial (TU. Aunque se esperaban comportamientos diferentes, los datos experimentales son consistentes frente a resultados TU, con diferencias entre 5.68 y 12.60 %.

  10. Diagnostic value of MRI for nerve root compression due to lumbar canal stenosis. Clinical and anatomic study

    Energy Technology Data Exchange (ETDEWEB)

    Seki, Michihiro; Kikuchi, Shinichi; Kageyama, Kazuhiro; Katakura, Toshihiko; Suzuki, Kenji [Fukushima Medical Coll. (Japan)

    1995-01-01

    Magnetic resonance imaging (MRI) was undertaken in 26 patients with surgically proven nerve root compression due to lumbar canal stenosis. The findings on coronary images were compared with those of selective radiculography to assess the diagnostic ability of MRI to determine the site of nerve root compression. Intermission and partial defect, which reflect nerve root compression, were seen in only 5 (19.2%) of 26 nerve roots on MRI, as compared with 20 (76.9%) on radiculography. Thus MRI alone was difficult to diagnose nerve root compression due to lumbar canal stenosis. Furthermore, the optimum angle of coronary views was determined in 13 cadavers. Para-sagittal views were found to be optimal for the observation of the whole running of the nerve root. Three-dimensional MRI was found to have a potential to diagnose nerve root compression in the intervertebral foramen and the distal part of the intervertebral foramen. (N.K.).

  11. Comparison of antimicrobial substantivity of root canal irrigants in instrumented root canals up to 72 h: An in vitro study

    Directory of Open Access Journals (Sweden)

    M N Shahani

    2011-01-01

    Full Text Available Disinfection of the root canal system is one of the primary aims of root canal treatment. This can be achieved through the use of various antimicrobial agents in the form of irrigants and medicaments. The antimicrobial substantivity of 2% chlorhexidine gluconate, 1% povidone iodine, 2.5% hydrogen peroxide followed by 2% sodium hypochlorite, and 2% sodium hypochlorite alone as irrigants was assessed in instrumented root canals. 2% chlorhexidine showed antimicrobial substantivity lasting up to 72 h, followed by 1% povidone iodine, and 2% sodium hypochlorite. Thus 2% chlorhexidine should be used as a final rinse irrigant in endodontic treatment protocols.

  12. El uso de Twitter como canal de información y conversación por parte de los medios convencionales

    OpenAIRE

    Castello-Martinez, Araceli

    2013-01-01

    Comunicación presentada en el XIV Foro de Investigación en Comunicación, Valencia, 18-19 febrero 2013. La comunicación se centra en estudiar cómo los medios convencionales hacen uso de la plataforma de microblogging Twitter no sólo como canal para ampliar la difusión de sus contenidos, sino también como fuente de información y espacio para entablar conversación con la audiencia a propósito de sus contenidos. Para ello se selecciona una muestra de los cinco soportes con mayor audiencia en c...

  13. Functional outcome of surgical management of degenerative lumbar canal stenosis

    Directory of Open Access Journals (Sweden)

    Rajendra Nath

    2012-01-01

    Conclusion: Operative treatment in patients of degenerative lumbar canal stenosis yields excellent results as observed on the basis of JOA scoring system. No patient got recurrence of symptoms of nerve compression.

  14. Scanning electron microscopic evaluation of root canal surfaces ...

    African Journals Online (AJOL)

    2014-07-15

    50. How to cite this article: Hema BS, Chandu GS, Shiraguppi VL. Scanning electron microscopic evaluation of root canal surfaces prepared with three rotary endodontic systems: Lightspeed, ProTaper and EndoWave. Niger J.

  15. Pneumocystis jirovecii infection of the external auditory canal : case ...

    African Journals Online (AJOL)

    primaquine, atovaquone and pentamidine isethionate.1,3 Although there is usually resolution of symptoms after medical therapy, surgical excision of lesions in the external auditory canal may be clinically indicated. Disseminated pneumocystosis, like ...

  16. Research progress of antagonistic interactions among root canal irrigations disease

    Directory of Open Access Journals (Sweden)

    Chen QU

    2013-07-01

    Full Text Available Root canal therapy is the most effective way to treat various pulposis and periapical disease. Simple mechanical apparatus can not clean root canal thoroughly, but may affect tight filling instead. It can achieve a satisfactory cleansing effect only when it is combined with a chemical solution. Irrigation fluid for root canal should possess the properties of tissue dissolution, antimicrobial, lubrication, and removal of smear layer. So far, no solution is able to fulfill all these functions. Therefore, a combined use of multiple irrigation solutions is suggested. It can not only achieve good effect in cleaning and disinfection, also it can lower the concentration of different solutions, thus reducing the side effects. Nevertheless, some experiments proved that antagonism existed among the chemicals used for irrigations. The purpose of present article is to review the antagonistic effect among the chemicals used for irrigation when they are used together for root canal treatment.

  17. Comparison of Two Canal Preparation Techniques Using Mtwo Rotary Instruments

    OpenAIRE

    Hamze, Faeze; Honardar, Kiamars; Nazarimoghadam, Kiumars

    2011-01-01

    INTRODUCTION Root canal preparation is an important process in endodontic therapy. Nickel-titanium (NiTi) rotary file system can be used in single length technique (simultaneous technique) without early coronal enlargement, as well as in crown-down method. The purpose of this in vitro study was to compare single length with crown-down methods’ shaping ability using Mtwo NiTi files. MATERIALS AND METHODS Fifteen acrylic-resin blocks containing simulated canals were divided into two experimenta...

  18. A Successful Endodontic Outcome with Non-Obturated Canals

    Science.gov (United States)

    Asgary, Saeed; Fazlyab, Mahta

    2015-01-01

    This case report represents the outcome of endodontic treatment in an infected mandibular molar with periradicular periodontitis and inherent poor prognosis of root canal treatment due to severe root curvature. The tooth was successfully treated by leaving the mesial root non-obturated, the canal orifices were coronally sealed with calcium enriched mixture cement and a definitive coronal amalgam restoration, was placed at the subsequent visit. PMID:26213546

  19. Nanodiamond?Gutta Percha Composite Biomaterials for Root Canal Therapy

    OpenAIRE

    Lee, Dong-Keun; Kim, Sue Vin; Limansubroto, Adelheid Nerisa; Yen, Albert; Soundia, Akrivoula; Wang, Cun-Yu; Shi, Wenyuan; Hong, Christine; Tetradis, Sotirios; Kim, Yong; Park, No-Hee; Kang, Mo K.; Ho, Dean

    2015-01-01

    Root canal therapy (RCT) represents a standard of treatment that addresses infected pulp tissue in teeth and protects against future infection. RCT involves removing dental pulp comprising blood vessels and nerve tissue, decontaminating residually infected tissue through biomechanical instrumentation, and root canal obturation using a filler material to replace the space that was previously composed of dental pulp. Gutta percha (GP) is typically used as the filler material, as it is malleable...

  20. Mesiodens within the nasopalatine canal: an exceptional entity

    OpenAIRE

    Georges Aoun; Ibrahim Nasseh

    2016-01-01

    A supernumerary tooth is one that is supplementary to the normal dentition. It can be found anywhere at the dental arch. A mesiodens is a supernumerary tooth located between the two maxillary central incisors usually palatally or within the alveolar process. Less frequently, the mesiodens is in relation with the nasal floor and the nasopalatine canal walls. This paper presents a very rare case of an impacted inverted mesiodens located inside the nasopalatine canal and found incidentally with ...

  1. Unusal canal configuration in maxillary and mandibular second molars

    Directory of Open Access Journals (Sweden)

    Ramachandran Ragunathan

    2016-01-01

    Full Text Available This clinical article describes three different case reports of maxillary and mandibular second molars with the unusual anatomy of single root with a single canal and their endodontic management. An unusual case of bilateralism is observed in the first two cases in the form of single-rooted second mandibular molars in both the quadrant of the same patient. The presence of maxillary second molar with single root and single canal in the third case is unusual.

  2. Rare case of gastrointestinal stromal tumor of the anal canal

    Directory of Open Access Journals (Sweden)

    Madhu Kumar

    2013-01-01

    Full Text Available Gastrointestinal stromal tumor (GIST is a rare mesenchymal neoplasm of the gastrointestinal tract. GIST of anal canal is very rare representing only 3% of all anorectal mesenchymal tumors. We report an extremely rare case of GIST of the anal canal in 60-years-old man with history of irregular bowel habits with dark colored stool mixed with blood and constipation from 6 month. Diagnosis was made on the basis of histomorphological and immunohistochemical examination.

  3. The Nicaragua Canal:Security And Economic Boom Or Bust

    Science.gov (United States)

    2014-04-01

    but is the property of the United States government. Abstract Since the 1800s nations and entrepreneurs have sought a maritime route across...across Central America to compete with the Panama Canal and thus secure his future with Nicaragua. Since the 1800s nations and entrepreneurs have...for the environmental effects that construction and operation of a canal could have on the regional ecosystem . As a result, environmentalists have

  4. CT findings of the osteoma of the external auditory canal

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Ha Young; Song, Chang Joon; Yoon, Chung Dae; Park, Mi Hyun; Shin, Byung Seok [Chungnam National University, School of Medicine, Daejeon (Korea, Republic of)

    2006-07-15

    We wanted to report the CT image findings of the osteoma of the external auditory canal. Temporal bone CT scanning was performed on eight patients (4 males and 4 females aged between 8 and 41 years) with pathologically proven osteoma of the external auditory canal after operation, and the findings of the CT scanning were retrospectively reviewed. Not only did we analyze the size, shape, distribution and location of the osteomas, we also analyzed the relationship between the lesion and the tympanosqumaous or tympanomastoid suture line, and the changes seen on the CT scan images for the patients who were able to undergo follow-up. All the lesions of the osteoma of the external auditory canal were unilateral, solitary, pedunculated bony masses. In five patients, the osteomas occurred on the left side and for the other three patients, the osteomas occurred on the right side. The average size of the osteoma was 0.6 cm with the smallest being 0.5 cm and the largest being 1.2 cm. Each of the lesions was located at the osteochondral junction in the terminal part of the osseous external ear canal. The stalk of the osteoma of the external auditory canal was found to have occurred in the anteroinferior wall in five cases (63%), in the anterosuperior wall (the tympanosqumaous suture line) in two cases (25%), and in the anterior wall in one case. The osteoma of the external auditory canal was a compact form in five cases and it was a cancellous form in three cases. One case of the cancellous form was changed into a compact form 35 months later due to the advanced ossification. Osteoma of the external auditory canal developed in a unilateral and solitary fashion. The characteristic image findings show that it is attached to the external auditory canal by its stalk. Unlike our common knowledge about its occurrence, osteoma mostly occurred in the tympanic wall, and this is regardless of the tympanosquamous or tympanomastoid suture line.

  5. Juntas de contracción en canales y depósitos de agua

    Directory of Open Access Journals (Sweden)

    Safránez, Carlos

    1977-12-01

    Full Text Available In view of the lack of Information available on the subject of contraction joints in canals and water tanks, and this being of great importance for water-tightness in this type of construction, the data considered as essential for planning joints has been presented in a systematic way. The most common of joints, and their characteristics, are mentioned and listed in accordance with their design and the procedure used for sealing them. The great importance of joint design and dimensions in relation to their performance has been highlighted. In the projects carried out, referring to this type of joint, we see there is a lack of common criteria regarding the minimum requisites and conditions which the joints must have in order to duly fulfill their mission. Experience has proven that the results obtained with contraction joints in canals and water tanks have not been totally satisfactory. In a large number of cases, bothersome and costly repairs were necessary to overercome deficiencies observed. In order to improve this situation, the different factors which influence the contraction joint's performance are discussed and they should be taken into account when planning the joints and their dimensions, in order to insure greatest efficiency.Vista la escasa información disponible sobre las juntas de contracción en canales y depósitos de agua, siendo indiscutible su gran importancia para la estanquidad de estas obras, se han expuesto, en forma sistemática, los datos considerados esenciales para enfocar debidamente el proyecto de las juntas. Se han indicado los tipos de juntas más corrientes, ordenadas de acuerdo con su diseño y con el procedimiento empleado para su sellado, señalando sus características. Se ha tratado de la importancia primordial del diseño y de las dimensiones de las juntas en relación con su comportamiento. En los proyectos de las juntas ejecutadas llama la atención la falta de una unidad de criterio sobre las

  6. Heterochrony, modularity, and the functional evolution of the mechanosensory lateral line canal system of fishes.

    Science.gov (United States)

    Bird, Nathan C; Webb, Jacqueline F

    2014-01-01

    The canals of the mechanosensory lateral line system are components of the dermatocranium, and demonstrate phenotypic variation in bony fishes. Widened lateral line canals evolved convergently in a limited number of families of teleost fishes and it had been hypothesized that they evolved from narrow canals via heterochrony and explore modularity in the lateral line system. Two species of cichlids with different canal phenotypes were used to test a hypothesis of heterochrony. Histological material prepared from ontogenetic series of Aulonocara stuartgranti (widened canals) and Tramitichromis sp. (narrow canals) was analyzed using ANCOVA to determine rates of increase in canal diameter and neuromast size (length, width) and to compare the timing of onset of critical stages in canal morphogenesis (enclosure, ossification). A faster rate of increase in canal diameter and neuromast width (but not length), and a delay in onset of canal morphogenesis were found in Aulonocara relative to Tramitichromis. However, rates of increase in canal diameter and neuromast size among canals, among canal portions and among canals segments reveal similar trends within both species. The evolution of widened lateral line canals is the result of dissociated heterochrony - acceleration in the rate of increase of both canal diameter and neuromast size, and delay in the onset of canal morphogenesis, in Aulonocara (widened canals) relative to Tramitichromis (narrow canals). Common rates of increase in canal diameter and neuromast size among canal portions in different dermatocranial bones and among canal segments reflect the absence of local heterochronies, and suggest modular integration among canals in each species. Thus, canal and neuromast morphology are more strongly influenced by their identities as features of the lateral line system than by the attributes of the dermatocranial bones in which the canals are found. Rate heterochrony manifested during the larval stage ensures that the

  7. A novel anatomical ceramic root canal simulator for endodontic training.

    Science.gov (United States)

    Robberecht, L; Chai, F; Dehurtevent, M; Marchandise, P; Bécavin, T; Hornez, J-C; Deveaux, E

    2017-11-01

    Endodontic therapy is often complicated and technically demanding. The aim of this study was to develop a reproducible biomimetic root canal model for pre-clinical and postgraduate endodontic training. A specific ceramic shaping technique (3D printing and slip casting of a root canal mould) was developed to reproduce canal systems with the desired shape and complexity using a microporous hydroxyapatite (HAp)-based matrix. The microstructural morphology, pore size and porosity, as well as the Vickers microhardness of the ceramic simulators (CS) were assessed and were compared with natural dentin and commercial resin blocks. The reproducibility of the root canal shapes was assessed using the Dice-Sørensen similarity index. Endodontic treatments, from refitting the access cavity to obturation, were performed on the CS. Each step was controlled by radiography. Many properties of the CS were similar to those of natural dental roots, including the mineral component (HAp), porosity (20%, porous CS), pore size (3.4 ± 2.6 μm) and hardness (120.3 ± 18.4 HV). We showed that it is possible to reproduce the radio-opacity of a tooth and variations in root canal morphology. The endodontic treatments confirmed that the CS provided good tactile sensation during instrumentation and displayed suitable radiological behaviour. This novel anatomic root canal simulator is well suited for training undergraduate and postgraduate students in endodontic procedures. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  8. Could spinal canal compression be a cause of polyneuropathy?

    Directory of Open Access Journals (Sweden)

    Richard Bostelmann

    2016-04-01

    Full Text Available Causality between spinal cord compression and polyneuropathy is difficult to define, especially under the circumstances that polyneuropathy can have many causes. Seven patients with spinal cord compression and electrophysiological signs of polyneuropathy were treated surgically on decompression of their spinal canal stenosis in the time from April 2010 to January 2013. Median follow up time was 9 months (2-23 months. Causes of polyneuropathy were: 1 patient with methotrexate-induced polyneuropathy, 1 endocrine-dysfunction-induced, 2 with diabetic- polyneuropathy, and 3 patients had unknown reasons. The localization of the spinal canal stenosis was also varying: 2 patients suffered of cervical spinal canal stenosis and 5 of lumbar. Decompressive surgery led to pain relieve in all patients initially. Surprisingly, also symptoms of polyneuropathy seemed to regress in all 7 patients for the first 5 months after surgery, and in 5 patients for the time of 9 months after surgery. There are two points we would like to emphasize in this short report. Since 5/7 patients with polyneuropathy and spinal canal stenosis improved clinically after surgery, surgery has a place in the treatment of such a combined pathology. Since it seems to be a possible causality between polyneuropathy of unknown origin and spinal cord stenosis, decompression of the spinal canal could also be a therapeutic step in a specific kind of polyneuropathy. Which patients could possibly have a spinal canal stenosis induced polyneuropathy remains a subject of further studies.

  9. Long-term cytotoxic effects of contemporary root canal sealers

    Directory of Open Access Journals (Sweden)

    Emmanuel Joao Nogueira Leal da SILVA

    2013-03-01

    Full Text Available Objectives The aim of the present study was to investigate the effects of root canal sealers on the cytotoxicity of 3T3 fibroblasts during a period of 5 weeks. Material and Methods Fibroblasts (3T3, 1×105 cells per well were incubated with elutes of fresh specimens from eight root canal sealers (AH Plus, Epiphany, Endomethasone N, EndoREZ, MTA Fillapex, Pulp Canal Sealer EWT, RoekoSeal and Sealapex and with elutes of the same specimens for 5 succeeding weeks after immersing in simulated body fluid. The cytotoxicity of all root canal sealers was determined using the MTT assay. Data were analyzed using ANOVA and Tukey's test. Results RoekoSeal was the only sealer that did not show any cytotoxic effects (p<0.05. All the other tested sealers exhibited severe toxicity initially (week 0. MTA Fillapex remained moderately cytotoxic after the end of experimental period. Toxicity of the other tested sealers decreased gradually over time. The evaluated root canal sealers presented varying degrees of cytotoxicity, mainly in fresh mode. Conclusions RoekoSeal had no cytotoxic effect both freshly mixed and in the other tested time points. MTA Fillapex was associated with significantly less cell viability when compared to the other tested root canal sealers.

  10. Effectiveness of Transmastoid Plugging for Semicircular Canal Dehiscence Syndrome.

    Science.gov (United States)

    Banakis Hartl, Renee M; Cass, Stephen P

    2018-01-01

    Objectives (1) Evaluate changes in subjective symptoms in patients following transmastoid canal plugging for superior semicircular canal dehiscence (SSCD) syndrome. (2) Quantify changes in hearing in patients who have undergone transmastoid canal plugging for SSCD syndrome. Study Design Case series with chart review. Setting Single tertiary care institution. Subjects and Methods We retrospectively reviewed patients with SSCD who underwent repair with canal plugging via a transmastoid approach between January 2012 and January 2017. Symptom severity was assessed prospectively (autophony, sound/pressure-induced vertigo, disequilibrium, aural fullness, and pulsatile tinnitus) and after surgery. Pure-tone and speech audiometry were measured before and after surgery. Two-sided Wilcoxon rank-sum tests were used to evaluate changes in subjective symptoms and audiometric outcomes. Results Seventeen patients (19 ears) met inclusion criteria. The superior canal was successfully plugged via the transmastoid approach in all cases. Patients reported a statistically significant improvement in autophony, vertigo, aural fullness, and pulsatile tinnitus ( P study, patients with SSCD demonstrated excellent hearing outcomes and resolution of most otologic symptoms after surgical repair. Transmastoid canal plugging, which has been described to date only in smaller case series, is a safe and effective alternative to the traditional middle cranial fossa approach.

  11. Superior Canal Dehiscence Syndrome: Lessons from the First 20 Years

    Directory of Open Access Journals (Sweden)

    Bryan K. Ward

    2017-04-01

    Full Text Available Superior semicircular canal dehiscence syndrome was first reported by Lloyd Minor and colleagues in 1998. Patients with a dehiscence in the bone overlying the superior semicircular canal experience symptoms of pressure or sound-induced vertigo, bone conduction hyperacusis, and pulsatile tinnitus. The initial series of patients were diagnosed based on common symptoms, a physical examination finding of eye movements in the plane of the superior semicircular canal when ear canal pressure or loud tones were applied to the ear, and high-resolution computed tomography imaging demonstrating a dehiscence in the bone over the superior semicircular canal. Research productivity directed at understanding better methods for diagnosing and treating this condition has substantially increased over the last two decades. We now have a sound understanding of the pathophysiology of third mobile window syndromes, higher resolution imaging protocols, and several sensitive and specific diagnostic tests. Furthermore, we have a treatment (surgical occlusion of the superior semicircular canal that has demonstrated efficacy. This review will highlight some of the fundamental insights gained in SCDS, propose diagnostic criteria, and discuss future research directions.

  12. Root canal preparation in endodontics: conventional versus laser methods

    Science.gov (United States)

    Goodis, Harold E.; White, Joel M.; Marshall, Sally J.; Marshall, Grayson W.; Moskowitz, Emrey

    1992-06-01

    Conventional cleaning and shaping of root canal systems employs hand and/or rotary instrumentation to remove the contents of the canal and shape the canal to receive a filling material. With the advent of the Nd:YAG laser system another method of accomplishing proper cleaning and shaping is evaluated. Single rooted teeth were radiographed bucco- lingually and mesio-distally and were divided into 2 groups. The first group was accessed and the root canal systems cleaned and shaped with a step back technique utilizing hand files and gates glidden burs. At completion of the procedure the teeth were again radiographed at the same positions as those prior to the procedure. The teeth were split longitudinally and examined under scanning electron microscopy to assess cleaning. The second group of teeth were accessed, and cleaning and shaping was accomplished using the Nd:YAG laser in combination with hand files and rotary instruments. These teeth were subjected to the same analysis as those in the first group. The before and after radiographs of each group were subjected to image analysis to determine effectiveness of the two methods in shaping the canal systems. We will discuss the ability of Nd:YAG to clean and shape root canal spaces and remove smear layer and organic tissue remnants from those areas.

  13. Cleaning of Root Canal System by Different Irrigation Methods.

    Science.gov (United States)

    Tanomaru-Filho, Mário; Miano, Lucas Martinati; Chávez-Andrade, Gisselle Moraima; Torres, Fernanda Ferrari Esteves; Leonardo, Renato de Toledo; Guerreiro-Tanomaru, Juliane Maria

    2015-11-01

    The aim of this study was to compare the cleaning of main and lateral canals using the irrigation methods: negative pressure irrigation (EndoVac system), passive ultrasonic irrigation (PUI) and manual irrigation (MI). Resin teeth were used. After root canal preparation, four lateral canals were made at 2 and 7 mm from the apex. Root canals were filled with contrast solution and radiographed pre- and post-irrigation using digital radiographic system [radiovisiography (RVG)]. The irrigation protocols were: MI1-manual irrigation [22 G needle at 5 mm short of working length-WL]; MI2-manual irrigation (30G needle at 2 mm short of WL); PUI; EV1-EndoVac (microcannula at 1 mm short of WL); EV2-Endovac (microcannula at 3 mm short of WL). The obtained images, initial (filled with contrast solution) and final (after irrigation) were analyzed by using image tool 3.0 software. Statistical analysis was performed by analysis of variance (ANOVA) and Tukey tests (5% significance level). EV1 and EV2, followed by PUI showed better cleaning capacity than manual irrigation (MI1 and MI2) (p irrigation and PUI promoted better cleaning of main and simulated lateral canals. Conventional manual irrigation technique may promote less root canal cleaning in the apical third. For this reason, the search for other irrigation protocols is important, and EndoVac and PUI are alternatives to contribute to irrigation effectiveness.

  14. Significance of temporal bone CT scan for exposure of the facial canal and the lateral semicircular canal in cholesteatoma

    Energy Technology Data Exchange (ETDEWEB)

    Sung, Ki Joon; Kim, Dong Jin; Kim, Myung Soon; Kim, Young Ju; Kweon, Joon [Wonju College of Medicine, Yonsei University, Wonju (Korea, Republic of)

    1991-09-15

    By reviewing retrospectively the HRCT findings in 130 surgically proven cases of chronic otitis media with cholesteatoma, we estimated the sensitivity, specificity, and positive predictability of the HRCT compared to surgical findings. For exposure of the facial canal, the sensitivity, specificity, and positive predictability was 59.7%, 84.9%, and 85.2% respectively. For exposure of the lateral semicircular canal, the sensitivity was 80.6%, the specificity 99.0%, and the positive predictability 96.2%. Conclusively, the diagnostic accuracy of preoperative temporal bone CT regarding the state of the lateral semicircular canal seems to be highly reliable. Gross invasion of the facial canal can be usually detected. However, relatively low sensitivity suggests that evaluation of the ultra-thin structures of the tympanic segment is often problematic.

  15. EQUILIBRIO DE FASES PARA SISTEMAS ETANOL-AGUA EN PRESENCIA DE POLIALCOHOLES Y SALES

    Directory of Open Access Journals (Sweden)

    LUIS RIOS

    2011-01-01

    Full Text Available Se propone un modelo termodinámico semiempírico para el equilibrio líquidovapor del sistema etanolagua con polialcoholes y sales. El modelo usa las ecuaciones GibbsDuhem y DebyeHückel, las cuales modifican el modelo UNIQUACE. Se consideran las fuertes interacciones químicas asociadas a los fenómenos de solvatación e hidratación de iones, y el concepto de solvatación del modelo de Ohe. Se tienen en cuenta las interacciones de corto alcance, dadas por las fuerzas de van der Waals, y las interacciones de largo alcanceconsideradas en el término de DebyeHückel. Se determinaron los parámetros empíricos de ajuste para los sistemas etanolaguapolialcoholcloruro de calcio y acetato de potasio; estos sistemas son de interés industrial debido a que la adición de polialcohol y sal mejora la eficiencia de la separación.. Las mediciones isobáricas del equilibrio líquidovapor se realizaron en un destilador Othmer. Este modelo termodinámico sería útil para diseñar y simular columnas para destilación extractiva aguaetanol.

  16. Avaliação da ansiedade e do viés de atenção no canal visual para estímulos emocionais em uma amostra não clínica Assessment of anxiety and attentional bias in the visual channel toward emotional stimuli in a non-clinical sample

    Directory of Open Access Journals (Sweden)

    Wilson Vieira Melo

    2012-04-01

    Full Text Available A ansiedade vem sendo estudada como fator capaz de influenciar a atenção visual seletiva em experimentos como a Visual Probe Detection Task (VPDT. Este estudo objetivou comparar o viés de atenção para imagens emocionais em pessoas com diferentes níveis de ansiedade de traço e estado usando a VPDT. Oitenta e dois estudantes universitários responderam ao IDATE. Na VPDT, utilizaram-se 12 pares de imagens com alto nível de ativação e valência negativa, pareadas com imagens controles neutras, do International Affective Picture System (IAPS. Os estímulos eram apresentados durante 200 m. O viés de atenção não foi diferente entre os participantes com baixos e altos níveis de ansiedade de traço e estado. Tais resultados indicaram que elas não são importantes para o viés de atenção para estímulos negativos com altos níveis de ativação. Além disso, é possível que o viés de atenção para estímulos ansiogênicos seja observado apenas em populações clínicas.Anxiety has been observed as a factor capable to influence the visual selective attention in experiments such as the Visual Probe Detection Task (VPDT. This study aimed to compare the attentional bias to emotional images in people with different levels of trait and state anxiety using a VPDT. Eighty-two undergraduate students performed VPDT and answered the State and Trait Anxiety Inventory. In VPDT, 12 pairs of images from International Affective Picture System (emotional image with high arousal level and negative valence/and one control, neutral were presented during 200 m. There was no attentional bias difference between the participants neither with low nor high levels of trait or state of anxiety. These results indicated that trait or state anxiety might not be important to attentional bias to negative and arousing visual stimuli. It is possible that just clinical populations with anxiety disorders often show attentional bias to anxiogenic stimuli.

  17. Síndrome da deiscência do canal semicircular superior: relato de dois casos

    Directory of Open Access Journals (Sweden)

    Carolina Calsolari Figueiredo de Godoy

    Full Text Available RESUMO A Síndrome da Deiscência do Canal Semicircular Superior (SDCSS é caracterizada pelo desgaste da camada óssea que recobre o canal semicircular superior. São sintomas comuns da SDCSS a presença de vertigem associada à nistagmos induzidos por estímulos sonoros intensos ou por modificações das pressões intracraniana ou da orelha média. O objetivo deste trabalho é descrever os achados audiólogicos e vestibulares de dois pacientes com diagnóstico de Síndrome da Deiscência do Canal Semicircular Superior, com diagnóstico confirmado por meio de tomografia computadorizada. Foram realizadas meatoscopia, anamnese, audiometria tonal e vocal seguida das medidas de imitância acústica, Weber audiométrico, pesquisa do fenômeno de Túlio e manobra de Valsalva, realizados pela mesma pesquisadora em uma única sessão. Foram observados gap aéreo-ósseo, curva timpanométrica tipo A e reflexos acústicos presentes. O gap aéreo-ósseo apresenta-se com maior amplitude nas frequências baixas. As queixas auditivas não foram relatadas pelas pacientes como os primeiros sintomas. O Weber mostrou lateralização, nos dois casos, confirmando a presença de gap. O fenômeno de Túlio apresentou-se positivo para vertigem em ambos os casos. A manobra de Valsalva apresentou alteração em apenas um caso.

  18. SIMULARE CONFLITTI PER IMPARARE A GESTIRLI: IL PROGETTO ACCORD

    Directory of Open Access Journals (Sweden)

    Davide Marocco

    2017-12-01

    Full Text Available SIMULATING CONFLICTS TO LEARN HOW TO MANAGE THEM: THE ACCORD Online role-play simulation game has recently received more attention in the training and education fields as a mechanism for providing generative learning in simulated contexts. Simulations can provide a solid platform upon which role-play games can be created and used to promote soft skills development. This form of active learning provides a unique tool for training people in different contexts that may be able to benefit from the availability of open source e-learning tools due to a common lack of access to affordable training and developmental resources. Within this paper a project to develop a new e-learning role-single-play game called, which exploits the output of the European project ENACT, will be described. ENACT is a simulation tool being developed to provide an affordable and accessible means for schools, enterprises, professional training and sport contexts to access on-line training to enhance their “soft skills”, and in particular negotiation competence. ACCORD project aim at applying such simulation-based technology for enhancing multicultural negotiation skills in teachers.

  19. Necrotic pulp tissue dissolution by passive ultrasonic irrigation in simulated accessory canals: impact of canal location and angulation.

    Science.gov (United States)

    Al-Jadaa, A; Paqué, F; Attin, T; Zehnder, M

    2009-01-01

    To evaluate whether passive ultrasonic irrigation (PUI) of 2.5% NaOCl would dissolve necrotic pulp tissue from simulated accessory root canals (SACs) better than passive placement of the irrigant, when temperature was equilibrated between the two treatments. Transparent root canal models (n = 6) were made from epoxy resin. SACs of 0.2 mm diameter were placed at defined angles and positions in the mid-canal and apical area. SACs were filled with necrotic bovine pulp tissue. PUI was performed five times for 1 min each with irrigant replenishment after every minute. Main canal temperature was measured after each minute, and a digital photograph was taken. In control experiments, mock treatments were performed with the same set-up without activation of the file using heated NaOCl to mimic the temperature created by PUI. Experiments were repeated five times. Digital photographs were analysed for the distance of dissolved tissue into the SACs in mm. Overall comparison (sum of dissolved tissue from all five accessory canals) between treatments was performed using paired t-test. Differences between SAC angulation and position after PUI were investigated using anova/Bonferroni (alpha temperature in the main canal to 53.5 +/- 2.7 degrees C after the fifth minute. PUI dissolved a total of 6.4 +/- 2.1 mm, mock treatment controlled for heat: 1.4 +/- 0.6 mm (P temperature.

  20. The effect of working length and root canal preparation technique on crack development in the apical root canal wall.

    Science.gov (United States)

    Adorno, C G; Yoshioka, T; Suda, H

    2010-04-01

    To evaluate the effects of working length and root canal preparation technique on crack development in the apical root canal wall. Seventy extracted mandibular premolars were mounted in a resin block with simulated periodontal ligaments and divided into seven groups according to preparation technique and working length: group A, step-back preparation with stainless steel files with working length set at the apical foramen and defined as root canal length (CL); group B, same as for A, except that the working length was CL-1 mm; group C, crown-down preparation with Profile instruments followed by an apical enlargement sequence with CL as working length and group D, same as for C, except that the working length was CL-1 mm. Groups E, F and G served as controls. Groups E and F were prepared only with the crown-down sequence up to CL and CL-1 mm, respectively. Group G was left unprepared. Digital images of the apical root surface (AS) were recorded before preparation, immediately after instrumentation and after removing the apical 1 mm (AS-1 mm) and 2 mm (AS-2 mm) of the root end. Working length significantly affected crack development at AS (P crack development at AS-1 mm (P crack development on the canal wall. Root canal preparation alone, regardless of the technique used, can potentially generate cracks on the apical root canal wall as well as the apical surface. Working 1- mm short of the apical foramen might produce fewer cracks in the apical region.

  1. Hardness gradients of dual-polymerized flowable composite resins in simulated root canals.

    Science.gov (United States)

    Ding, Hong; Meng, Xiangfeng; Luo, Xiaoping

    2014-11-01

    Information is lacking of the polymerization depth of dual-polymerized flowable composite resin foundation materials in simulated root canals. The purpose of this study was to investigate the hardness gradients and the polymerization depth of dual-polymerized flowable composite resin foundation materials in simulated root canals. Slots in steel split cylinders with 1 open end were filled with the following 6 materials: Luxa Core, Para Core, Clearfil DC Core, Multi Core Flow, Gradia Core, and Core-Flo DC. After filling, they were subjected to a light intensity of 1250 mWcm(-2) with a light-emitting diode light through their open ends for 20 seconds. The resulting specimens were stored in a light-proof box at 37°C, and the Knoop hardness gradients of each polymerized material were measured after 0.5 hour, 24 hours, and 120 hours. The surface readings were obtained in 1-mm intervals at 1 mm to 10 mm away from the open ends. The collected data were analyzed by 2-way ANOVA and the Student-Newman-Keuls test (α=.05). Before the Knoop hardness numbers of the 6 materials became stable, they decreased gradually in depth at each time point (Phardness numbers of Luxa Core and Core-Flo DC reached stability at a depth of 3 mm, Para Core at 4 mm, and Clearfil DC Core, Multi Core Flow, and Gradia Core at 5 mm. Additionally, at 120 hours after exposure, the ratios of the Knoop hardness numbers at a depth of 5 mm to those at 1 mm were 63.08% for Luxa Core, 70.48% for Clearfil DC Core, 81.38% for Para Core, 80.49% for Gradia Core, 86.30% for Multi Core Flow, and 96.28% for Core-Flo DC. In simulated root canals, the flowable composite resin foundation materials tested had better polymerization under dual polymerizing than under chemical polymerizing, and their chemical-polymerized capabilities could determine the definitive polymerization depth. Copyright © 2014 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

  2. Semicircular canal plane head impulses detect absent function of individual semicircular canals.

    Science.gov (United States)

    Cremer, P D; Halmagyi, G M; Aw, S T; Curthoys, I S; McGarvie, L A; Todd, M J; Black, R A; Hannigan, I P

    1998-04-01

    We studied the human vestibulo-ocular reflex (VOR) in response to head 'impulses': brief, unpredictable, passive, high-acceleration (up to 4000 degrees/s2), low-amplitude (20-30 degrees) head rotations. We delivered the head impulses approximately in the plane of the semicircular canal (SCC) being tested. To test the anterior and posterior SCCs, the head impulses were delivered in a diagonal plane, midway between the frontal (roll) and sagittal (pitch) planes. We recorded head and eye position in three dimensions with scleral search coils in nine normal subjects, seven patients following unilateral surgical vestibular neurectomy and three patients following unilateral posterior SCC occlusion. In the post-surgical patients we demonstrated a severe, permanent VOR gain deficit (0.2-0.3) for head impulses directed toward any single non-functioning SCC. The sensitivity of the test depends on the physiological properties of primary vestibular afferents, and its specificity depends on the anatomical orientation of the SCCs. The diagonal head impulse is the first test of individual vertical SCC function in humans, and together with the horizontal head impulse, forms a comprehensive battery of SCC-plane tests. These canal-plane impulses could be useful in evaluating patients with vertigo or other vestibular disorders.

  3. Water losses from irrigation canals evaluation: comparison among different methodologies

    Science.gov (United States)

    Clemente, Paolo; De Luca, Domenico Antonio; Antonella Dino, Giovanna; Lasagna, Manuela

    2013-04-01

    The research investigates the field methodologies to evaluate water losses from canals, in order to find a reliable method to identify and quantify them. This study was conducted in five canal lines in Piedmont, north-western Italy, different for hydraulic, morphological, geological and hydrogeological contexts (De Luca et alii, 2012). At a regional scale, Piedmont network consists of several tens of thousands km of irrigation canals. The loss of water due to seepage from irrigation canals constitutes a substantial part of the usable water. Irrigation canals placed in natural soil or fine and coarse sediments are characterized by water losses ranging from 20 % to more than 50 %. These losses cause economic, hydrogeological and environmental consequences: water losses evaluation from irrigation canals in the basis for the sustainable water resource use and management. First, hydrogeological and hydrological characterisation of the study area and of the bottom of the irrigation canals was carried out for every investigated canal, in order to evaluate the relationships between groundwater and stream water (eg. piezometric and hydrogeochemical survey campaigns, infiltrometry tests, penetrometric tests and electrical tomographies, soil characterizations from the bottom of investigated canals). The canals seepage rates were subsequently estimated using different methodologies: empirical formulas, inflow-outflow tests and double tracer tests. The empirical formulas applied for the study underestimated the real amount of the losses probably due to the scarce number of the considered variables. Then the canals seepage rates were evaluated employing inflow-outflow tests, considered the best tool by several authors. This method allows the determination of seepage quantities measuring inflow and outflow of a canal test reach either by instruments. The canal discharge was evaluated using a current meter. This method, even if easy to apply and practical, is not efficient

  4. Comparative evaluation of canal cleaning ability of various rotary endodontic filesin apical third: A scanning electron microscopic study

    Directory of Open Access Journals (Sweden)

    Ganesh Ranganath Jadhav

    2016-01-01

    Conclusion: In apical third of root canal, SAF showed statistically significant canal cleaning ability due to combined effect of continuous streaming irrigation with effectively replacing the irrigant from the apical portion of the root canal, irrigants activation through the creation of turbulence, and its self-adapting design to root canal anatomy with a scrubbing motion on the canal walls.

  5. Endodontic management of mandibular first molar with seven canals using cone-beam computed tomography

    Directory of Open Access Journals (Sweden)

    Ankur Mahesh Banode

    2016-01-01

    Full Text Available The endodontic treatment of a mandibular molar with aberrant canal configuration can be diagnostically and clinically challenging. Successful endodontic therapy thus depends on the clinician's ability to anticipate and look for these aberrant variations. A mandibular first molar with seven canals represents a rare anatomical variant, particularly when four canals are found in distal root. Based on in vitro studies, its incidence is reported to be between 0.2% and 3%. With the advent of cone-beam computed tomography (CBCT as an adjunctive diagnostic aid, the determination of root canal anatomy in teeth with complex canal configurations has become more precise. The present case report discusses successful nonsurgical management of radix entomolaris along with middle mesial canal and middle distal canal in mandibular first molar with seven canals (four canals in distal and three in mesial employing CBCT as an adjunctive diagnostic aid to conventional radiography.

  6. Cervical spinal canal narrowing and cervical neurologi-cal injuries

    Directory of Open Access Journals (Sweden)

    ZHANG Ling

    2012-04-01

    Full Text Available 【Abstract】Cervical spinal canal narrowing can lead to injury of the spinal cord and neurological symptoms in-cluding neck pain, headache, weakness and parasthesisas. According to previous and recent clinical researches, we investigated the geometric parameters of normal cervical spinal canal including the sagittal and transverse diameters as well as Torg ratio. The mean sagittal diameter of cervical spinal canal at C 1 to C 7 ranges from 15.33 mm to 20.46 mm, the mean transverse diameter at the same levels ranges from 24.45 mm to 27.00 mm and the mean value of Torg ratio is 0.96. With respect to narrow cervical spinal canal, the following charaterstics are found: firstly, extension of the cervical spine results in statistically significant stenosis as compared with the flexed or neutral positions; secondly, females sustain cervical spinal canal narrowing more easily than males; finally, the consistent narrowest cervical canal level is at C 4 for all ethnicity, but there is a slight variation in the sagittal diameter of cervical spinal stenosis (≤14 mm in Whites, ≤ 12 mm in Japanese, ≤13.7 mm in Chinese. Narrow sagittal cervical canal diameter brings about an increased risk of neurological injuries in traumatic, degenerative and inflam-matory conditions and is related with extension of cervical spine, gender, as well as ethnicity. It is hoped that this re-view will be helpful in diagnosing spinal cord and neuro-logical injuries with the geometric parameters of cervical spine in the future. Key words: Spinal cord injuries; Spinal stenosis; Trauma, nervous system

  7. Canal configuration of mandibular first premolars in an Egyptian population

    Directory of Open Access Journals (Sweden)

    Hatem A. Alhadainy

    2013-03-01

    Full Text Available The purpose of this study was to investigate canal configuration of mandibular first premolars in an Egyptian population. Two hundred fifty human extracted mandibular first premolars were collected from Egyptian patients and a small hole in the center of the occlusal surface of each tooth was made perforating the roof of the pulp chamber. Teeth were decalcified by immersing in nitric acid and dehydrated in ascending concentrations of ethyl alcohol. A waterproof black ink was passively injected from the occlusal hole into pulp system and stained teeth were immersed in methyl salicylate solution for clearing. Standardized pictures of the cleared teeth were obtained and anatomical features of the root canal were observed. The average length of the mandibular first premolar teeth was 22.48 ± 1.74 mm, one-rooted teeth were 96.8% and the two-rooted were 3.2%. Vertucci Type I canal configuration represented the highest percentage (61.2% followed by Type V (16.4%, Type IV (13.2%, Type II (5.6% and Type III (2.8%. Vertucci Type VI canal configuration represented the lowest percentage (0.4% and a complex configuration was found in one tooth. Accessory canals were detected in 22.8% and inter-canal connections were observed in 24.8% while 54% showed apical delta. Such knowledge is clinically useful for localization and negotiation of canals of mandibular first premolar, as well as their subsequent management in Egyptian population.

  8. Lumbar spinal canal size of sciatica patients

    Energy Technology Data Exchange (ETDEWEB)

    Hurme, M.; Alaranta, H.; Aalto, T.; Knuts, L.R.; Vanharanta, H.; Troup, J.D.G. (Turku City Hospital (Finland). Dept. of Surgery; Social Insurance Institution, Turku (Finland). Rehabilitation Research Centre; Helsinki Univ. (Finland). Dept. of Physical Medicine and Rehabilitation; Liverpool Univ. (UK). Dept. of Orthopaedic and Accident Surgery)

    Seven measures at the three lowest lumbar interspaces were recorded from conventional radiographs of the lumbar spines of 160 consecutive patients with low back pain and sciatica admitted for myelography and possible surgery. Eighty-eight patients were operated upon for disc herniation, and of the conservatively-treated 72 patients, 18 had a pathologic and 54 a normal myelogram. The results were evaluated after one year using the occupational handicap scales of WHO. Correlations of radiographic measures to stature were moderate and to age small. After adjusting for stature and age, only the male interpedicular distances and the antero-posterior diameter of intervertebral foramen at L3 were greater than those of females. The males with a pathologic myelogram had smaller posterior disc height at L3 and a smaller interarticular distance at L3 and L4 than those with normal myelogram, likewise the midsagittal diameter at L3 and L4 in females. In all patients other measures besides posterior disc height were smaller than those for low back pain patients (p<0.001) or for cadavers (p<0.001). The only correlation between measures and clinical manifestations was between pedicular length at L3 and limited straight leg raising. Where the disc material had been extruded into the spinal canal, the interpedicular distance was significantly wider. Only anterior disc height at L3 revealed differences between good and poor outcome one year after surgery, as did the interarticular distance at S1 in patients with normal myelogram after conservative treatment. (orig.).

  9. Propuesta sobre la factibilidad financiera del comercio electrónico como canal de exportación hacia Estados Unidos de América para las pequeñas empresas productoras de artesanías de El Salvador, caso práctico: ECO-BAMBU, Artesanías y Diseño

    OpenAIRE

    Torres Parada, Pablo Ernesto; Argueta Ramírez, Nelson de Jesús

    2009-01-01

    El desarrollo del trabajo de grado se enfocó en la necesidad que existe en la industria de artesanías, como caso práctico se estudió la empresa ECO-BAMU cuyo giro comercial es la elaboración de artesanías en un 90. Artesanal de diseños exclusivos en el mercado, explotando la materia prima bambú, morro y semillas cuyas ventas mensuales hacen un promedio de $ 5,000.00, si aplicar el comercio electrónico. En la aplicación de la herramienta financiera, flujo de efectivo proyectado para cinco año...

  10. Modelo resorte-paríicula para telas hiperlasticas

    Directory of Open Access Journals (Sweden)

    MANUEL GARCÍA

    2007-01-01

    Full Text Available Este artículo presenta un modelo computacional para la simulación de telas hiperelásticas. El modelo propuesto tiene un enfoque multi−partículas y simula la interacción de un material textil con un objeto deformante. La tela está representada por mallas rectangulares compuestas por resortes, este hecho permite al modelo comportarse ortotrópicamente y en consecuencia es posible simular sus propiedades en ambos sentidos. Las relaciones constitutivas del material preservan las capacidades hiperelásticas naturales de la tela. En el modelo desarrollado aquí, inicialmente la tela se encuentra en su estado natural no deformado. Luego se le da una deformación inicial que garantice el no contacto o intersección con el objeto deformante. Finalmente, la tela deformada es liberada, en consecuencia ella comienza a moverse iterativamente hacia a una posición de equilibrio. La posición final de equilibrio es alcanzada cuando las fuerzas internas son balanceadas por las fuerzas externas de contacto causadas por el objeto. Esto se logra cuando el criterio de parada ha sido satisfecho.

  11. Methodology for Automatic Generation of Models for Large Urban Spaces Based on GIS Data/Metodología para la generación automática de modelos de grandes espacios urbanos desde información SIG/

    Directory of Open Access Journals (Sweden)

    Sergio Arturo Ordóñez Medina

    2012-12-01

    Full Text Available In the planning and evaluation stages of infrastructure projects, it is necessary to manage huge quantities of information. Cities are very complex systems, which need to be modeled when an intervention is required. Suchmodels allow us to measure the impact of infrastructure changes, simulating hypothetic scenarios and evaluating results. This paper describes a methodology for the automatic generation of urban space models from GIS sources. A Voronoi diagram is used to partition large urban regions and subsequently define zones of interest. Finally, some examples of application models are presented, one used for microsimulation of traffic and another for air pollution simulation.En las etapas de planeación y evaluación de proyectos de infraestructura es necesario manejar grandes cantidades de información. Las ciudades son sistemas complejos que deben ser modeladas para ser intervenidas. Estos modelos permitirón medir el impacto de los cambios de infraestructura, simular escenarios hipotéticos y evaluar resultados. Este artículo describe una metodología para generar automáticamente modelos espaciales urbanos desde fuentes SIG: Un diagrama de Voronoi es usado para dividir grandes regiones urbanas, y a continuación serán definidas las zonas de interés. Finalmente, algunos ejemplos de modelos de aplicación serán presentados, uno usado para microsimulación de tráfico y el otro para simular contaminación atmosférica.

  12. Crecimiento y características de canal en corderas tratadas con clorhidrato de zilpaterol durante primavera y verano

    Directory of Open Access Journals (Sweden)

    Ulises Macías-Cruz

    2013-01-01

    Full Text Available Se utilizaron 44 corderas Dorper x Pelibuey con peso vivo promedio de 24.56±0.70 kg para evaluar el efecto del clorhidrato de zilpaterol (CZ sobre el comportamiento productivo y algunas características de canal en épocas de primavera (n=24 y verano (n=20, bajo condiciones áridas del noroeste de México. En cada época, las corderas fueron colocadas en corraletas individuales y divididas en dos grupos para ser alimentadas sin CZ (SCZ o con 10 mg de CZ/ animal/día (CCZ durante 32 días. Posteriormente, todas las corderas fueron sacrificadas. La información se sometió a un análisis de varianza con un diseño de bloques completamente al azar con arreglo factorial 2x2. Las corderas CCZ de primavera presentaron mayor (P0.05 por efecto del CZ; contrariamente, el peso de canal caliente y fría, y la área del músculo Longissimus dorsi fueron mayores (P<0.05 en corderas CCZ. Solamente consumo de alimento y área del músculo Longissimus dorsi fueron afectados (P<0.01 por época. En conclusión, las altas temperaturas registradas en verano limitan el funcionamiento de CZ para mejorar el crecimiento y la eficiencia alimenticia de corderas de pelo finalizadas en corral, pero no las características de canal.

  13. El bagre de canal (Ictalurus punctatus Rafinesque, 1818: estado actual y problemática en México

    Directory of Open Access Journals (Sweden)

    Ana Laura Lara-Rivera

    2015-07-01

    Full Text Available El bagre de canal (Ictalurus punctatus es uno de los peces endémicos de Norte América con mayor potencial para la acuicultura. A pesar de esto, los datos sobre su distribución actual son escasos y se desconocen muchos aspectos de su dinámica y desempeño productivo. En el presente estudio se reportan los resultados de una búsqueda bibliográfica y análisis de campo que permiten describir la situación actual del bagre de canal con respecto a su distribución geográfica histórica y actual, así como de la problemática que enfrentan los sistemas productivos de esta especie en México. Se identificó la falta de información e indicadores que permitan conocer la extensión de su hábitat natural, movilización o potencial productivo. La calidad y disponibilidad del agua figuran entre las principales problemáticas de la industria; el alimento supone el mayor gasto para los productores y existe gran heterogeneidad de manejo tanto en granjas reproductoras como de engorde, gran parte de la dinámica productiva sigue un modelo de ensayo y error. Se requiere optimizar y homologar los procesos del sistema productivo de bagre de canal, así como caracterizar correctamente las poblaciones domésticas y silvestres para aprovechar al máximo su potencial.

  14. Canal switch after canalith repositioning procedure for benign paroxysmal positional vertigo.

    Science.gov (United States)

    Lin, Giant C; Basura, Gregory J; Wong, Hiu Tung; Heidenreich, Katherine D

    2012-09-01

    Canal switch is a complication following canalith repositioning procedure (CRP) for posterior canal benign paroxysmal positional vertigo (BPPV). Instead of being returned to the utricle, the loose otoconia migrate into the superior or horizontal semicircular canal. Patients remain symptomatic, and treatment can be ineffective unless the switch is recognized and additional repositioning maneuvers directed toward the appropriate semicircular canal are performed. This report provides the first videographic documentation of canal switch involving conversion of unilateral posterior semicircular canal BPPV to geotropic horizontal canalithiasis. Copyright © 2012 The American Laryngological, Rhinological, and Otological Society, Inc.

  15. Strategies of Coping With Stress During Root Canal Therapy

    Directory of Open Access Journals (Sweden)

    Zare Jahromi

    2015-12-01

    Full Text Available Background Endodontic treatment is one of the stress producing situations. Objectives The purpose of this article was to determine the most stressful stage of root canal therapy among endodontists, endodontic residents, and undergraduate dental students and offering some strategies for reducing stress during this treatment. Patients and Methods This descriptive survey comprised three groups. Thirty-six endodontists, 41 endodontic residents, and 47 undergraduate dental students selected by convenience sampling. Participants were asked about age, sex, the most stressful stage of root canal therapy and stress reducing strategies during the procedure. Results The most stressful stage of root canal therapy was endodontic treatment for children in male endodontists and residents, preparing access cavity on crowns in female endodontists, obturation of apically root Resorped canals in female residents, obturation in female students, and preparing access cavity on molar teeth in male students. The most suggested strategy for reducing stress during root canal therapy was related to experience, knowledge, enough study, and technical mastery. Conclusions It is required to consider the strategies during student education in dental schools for both under and post-graduation dental students and better to follow them in workshops for other dentists and even endodontists.

  16. Slope restoration for a 100-year old canal

    Energy Technology Data Exchange (ETDEWEB)

    Skaggs, R.L.; Lewis, S.W. [Condor Earth Technologies, Inc., Sonora, CA (United States); Liebersbach, D.C. [Turlock Irrigation District, CA (United States)] [and others

    1995-12-31

    Turlock Irrigation District (TID) is located in the northern portion of the fertile San Joaquin Valley of California. TID`s primary water supply is conveyed from the 100-year-old LaGrange Diversion Dam via their historic Upper Main Canal. The original canal was constructed by excavating into slate bedrock for the uphill (cut) bank, and constructing unmortared rock walls and rock fill for the downhill (fill) embankment; the excavation was then lined with concrete. Soil fill raises of the downhill embankment over the last 30 years have reduced the slope stability to unacceptable levels in the steepest embankment areas. In March of 1994, two surficial slides prompted investigation of the long term embankment stability in the Warehouse Slide Area. Based on results of analysis for various stabilization scenarios, TID chose a stabilization method which included: (1) excavation of an access bench below the existing canal, (2) installation of steel pipe piles through the existing rock fill and into the bedrock, (3) construction of a mechanically stabilized earth (MSE) retaining wall and (4) construction of a soil-cement canal roadway pavement. The design was chosen by the owner because of cost competitiveness compared to other design alternatives and because the construction sequence allowed uninterrupted use of the canal. By using local river cobble for the MSE wall facing material, TID met the desired 50-year design life of the repair while maintaining the area`s historic visual features.

  17. Nanodiamond-Gutta Percha Composite Biomaterials for Root Canal Therapy.

    Science.gov (United States)

    Lee, Dong-Keun; Kim, Sue Vin; Limansubroto, Adelheid Nerisa; Yen, Albert; Soundia, Akrivoula; Wang, Cun-Yu; Shi, Wenyuan; Hong, Christine; Tetradis, Sotirios; Kim, Yong; Park, No-Hee; Kang, Mo K; Ho, Dean

    2015-11-24

    Root canal therapy (RCT) represents a standard of treatment that addresses infected pulp tissue in teeth and protects against future infection. RCT involves removing dental pulp comprising blood vessels and nerve tissue, decontaminating residually infected tissue through biomechanical instrumentation, and root canal obturation using a filler material to replace the space that was previously composed of dental pulp. Gutta percha (GP) is typically used as the filler material, as it is malleable, inert, and biocompatible. While filling the root canal space with GP is the standard of care for endodontic therapies, it has exhibited limitations including leakage, root canal reinfection, and poor mechanical properties. To address these challenges, clinicians have explored the use of alternative root filling materials other than GP. Among the classes of materials that are being explored as novel endodontic therapy platforms, nanodiamonds (NDs) may offer unique advantages due to their favorable properties, particularly for dental applications. These include versatile faceted surface chemistry, biocompatibility, and their role in improving mechanical properties, among others. This study developed a ND-embedded GP (NDGP) that was functionalized with amoxicillin, a broad-spectrum antibiotic commonly used for endodontic infection. Comprehensive materials characterization confirmed improved mechanical properties of NDGP over unmodified GP. In addition, digital radiography and microcomputed tomography imaging demonstrated that obturation of root canals with NDGP could be achieved using clinically relevant techniques. Furthermore, bacterial growth inhibition assays confirmed drug functionality of NDGP functionalized with amoxicillin. This study demonstrates a promising path toward NDGP implementation in future endodontic therapy for improved treatment outcomes.

  18. Stereomicroscopic Dye Leakage Measurement of Six Different Root Canal Sealers.

    Science.gov (United States)

    Ballullaya, Srinidhi V; Vinay, Vusurumarthi; Thumu, Jayaprakash; Devalla, Srihari; Bollu, Indira Priyadarshini; Balla, Sagarika

    2017-06-01

    Hermetic sealing of the root canal is the most desirable outcome of any root canal treatment, but almost always the filling of the root canal is defective, which is a multifactorial outcome. One such factor majorly influencing the obturation is the root canal sealer used. The present study was done for evaluating microleakage in different root canal sealers. Sixty extracted human single rooted teeeth were used in this in-vitro study. Sealers tested for microleakage in this study were zinc oxide eugenol based sealer, Sealapex, AH Plus, MTA Plus, EndoRez, Endosequence BC. All the specimens were examined under stereomicroscope for microleakage and the obtained data were statistically analysed using One-way ANOVA test and Tukey's multiple comparision tests using the software GraphPad Prism 7.02. The Endosequence BC group showed the least dye leakage and the highest leakage was seen in Zinc oxide Eugenol based sealer. Bio ceramic salers being hydrophilic show better sealing ability compared to resin based and eugenol based sealers.

  19. Micro-Machined Flow Sensors Mimicking Lateral Line Canal Neuromasts

    Directory of Open Access Journals (Sweden)

    Hendrik Herzog

    2015-08-01

    Full Text Available Fish sense water motions with their lateral line. The lateral line is a sensory system that contains up to several thousand mechanoreceptors, called neuromasts. Neuromasts occur freestanding on the skin and in subepidermal canals. We developed arrays of flow sensors based on lateral line canal neuromasts using a biomimetic approach. Each flow sensor was equipped with a PDMS (polydimethylsiloxane lamella integrated into a canal system by means of thick- and thin-film technology. Our artificial lateral line system can estimate bulk flow velocity from the spatio-temporal propagation of flow fluctuations. Based on the modular sensor design, we were able to detect flow rates in an industrial application of tap water flow metering. Our sensory system withstood water pressures of up to six bar. We used finite element modeling to study the fluid flow inside the canal system and how this flow depends on canal dimensions. In a second set of experiments, we separated the flow sensors from the main stream by means of a flexible membrane. Nevertheless, these biomimetic neuromasts were still able to sense flow fluctuations. Fluid separation is a prerequisite for flow measurements in medical and pharmaceutical applications.

  20. Labyrinthine artery aneurysm as an internal auditory canal mass.

    Science.gov (United States)

    Diaz, Rodney C; Konia, Thomas; Brunberg, James

    2014-08-01

    We present the first case report of a labyrinthine artery aneurysm masquerading as an internal auditory canal tumor. A 72-year-old woman presented with sudden onset right facial paralysis, facial pain, hearing loss, and vertigo. She demonstrated dense right-sided facial paralysis involving all branches of the facial nerve, left beating horizontal nystagmus, and anacusis of the right ear. Magnetic resonance imaging with contrast demonstrated a 6 × 7 mm peripherally enhancing lesion with lack of central uptake filling the right internal auditory canal. The patient elected to proceed with translabyrinthine approach to the internal auditory canal for definitive resection of the mass as well as to decompress the neural structures of the internal auditory canal in an attempt to recover neural function, particularly of the facial nerve. Intraoperatively, the internal auditory canal mass was resected with minimal difficulty, with intraoperative dissection notable for brisk bleeding at the medial base of the tumor just as the tumor was dissected off its medial fibrous attachments. Final pathology of the resected mass revealed a blood vessel with mucinous degeneration of the medial layer of the vessel wall, with immunohistochemical staining confirming the presence and structure of aneurysmal blood vessel.

  1. Partial ear canal ablation and lateral bulla osteotomy in rabbits.

    Science.gov (United States)

    Eatwell, K; Mancinelli, E; Hedley, J; Keeble, E; Kovalik, M; Yool, D A

    2013-06-01

    Six lop rabbits were presented with clinical signs of otitis media or externa. The presence of disease was confirmed by computerized tomography examination, with two rabbits suffering from bilateral disease. The rabbits were anaesthetized and underwent surgery of the affected bulla. Rabbits with bilateral disease had a minimum of 2 weeks between procedures. A single vertical incision was made over the base of the vertical canal, which was bluntly dissected free from surrounding tissue. The ventral portion of the vertical canal was removed and a lateral bulla osteotomy was performed. The mucosa at the base of the dorsal vertical canal was apposed and the aural cartilage sutured to form a blind-ending pouch open at the pretragic incisure. Histopathological samples taken from the dorsal margin of the vertical canal yielded subtle and non-specific changes in the six samples submitted. All rabbits were discharged within 48 hours of surgery. The cosmetic outcome was excellent with animals retaining visually normal aural anatomy. The partial ear canal ablation/lateral bulla osteotomy procedure is quick and has a good cosmetic result when performed in rabbits. © 2013 British Small Animal Veterinary Association.

  2. CT and MR Imagings of Semicircular Canal Aplasia

    Energy Technology Data Exchange (ETDEWEB)

    Shin, Chung Hee; Hong, Hyun Sook; Yi, Beom Ha; Cha, Jang Gyu; Park, Seong Jin; Kim, Dae Ho; Lee, Hae Kyung; Kim, Shi Chan [Soonchunhyang University Bucheon Hospital, Bucheon (Korea, Republic of)

    2009-07-15

    To evaluate the clinical, CT and MR imaging findings of semicircular canal (SCC) aplasia and to evaluate if a correlation exists between these findings and the associated anomalies or syndromes. This study retrospectively reviewed the CT and MRI findings of five patients with SCC aplasia. The CT and MR findings were analyzed for SCC, direction of facial nerve canal, cochlea, vestibule, oval or round window, middle ear ossicles, and internal auditory canal (IAC). The subjects included three boys and two girls ranging in age from one to 120 months (mean age; 51 months). Four of the subjects had the CHARGE syndrome, and one had the Goldenhar syndrome. Moreover, four subjects had sensorineural hearing loss and one had combined hearing loss. The course of the facial nerve canal was abnormal in all five cases. Moreover, trapped cochlea and dysplastic modiolus were each observed in one case. Four subjects had atresia of the oval window; whereas ankylosis of the ossicles was present in three subjects. IAC stenosis was present in one patient with the CHARGE syndrome. The aberrant course of the facial nerve canal, atresia of the oval window, and abnormal ossicles were frequently associated in patients with SCC aplasia. In addition, the Goldenhar and CHARGE syndromes were also commonly associated syndromes.

  3. Instrumento para la simulación de correcciones oftálmicas multifocales

    OpenAIRE

    Dorronsoro, Carlos; Marcos, Susana

    2010-01-01

    Instrumento para la simulación de correcciones oftálmicas multifocales. Se presenta un instrumento para la simulación de correcciones oftálmicas multifocales que comprende dos canales ópticos con diferentes potencias ópticas en los haces procedentes del objeto observado, en el que al menos uno de los canales comprende un sistema de Badal. Este instrumento proporciona simultáneamente imágenes de objetos enfocados de lejos y cerca. El sistema proporciona los mismos au...

  4. The best radiographic method for determining root canal morphology in mandibular first premolars: A study of Chinese descendants in Taiwan

    Directory of Open Access Journals (Sweden)

    Yu Sun

    2016-06-01

    Conclusion: Combined X-ray analyses, such as performing the buccolingual view for identification of canal bifurcation and canal continuity, may increase the accuracy of identifying complex root canal morphology.

  5. Microstructure and wettability of root canal dentine and root canal filling materials after different chemical irrigation

    Energy Technology Data Exchange (ETDEWEB)

    Antonijevic, Djordje; Milovanovic, Petar [Laboratory for Anthropology, Institute for Anatomy, Faculty of Medicine, University of Belgrade, Belgrade (Serbia); Brajkovic, Denis [Department of Dentistry, Faculty of Medical Sciences, University of Kragujevac, Kragujevac (Serbia); Ilic, Dragan [Department of Restorative Medicine, School of Dental Medicine, University of Belgrade, Belgrade (Serbia); Hahn, Michael; Amling, Michael [Department of Osteology and Biomechanics (IOBM), University Medical Center Hamburg-Eppendorf, Lottestr. 55A, 22529 Hamburg (Germany); Rakocevic, Zlatko [Laboratory for Atomic Physics, Institute for Nuclear Science “Vinca”, University of Belgrade, Belgrade (Serbia); Djuric, Marija [Laboratory for Anthropology, Institute for Anatomy, Faculty of Medicine, University of Belgrade, Belgrade (Serbia); Busse, Björn, E-mail: b.busse@uke.uni-hamburg.de [Department of Osteology and Biomechanics (IOBM), University Medical Center Hamburg-Eppendorf, Lottestr. 55A, 22529 Hamburg (Germany)

    2015-11-15

    Graphical abstract: - Highlights: • Different irrigation solutions and disinfectants were used for treatment of root canal dentine and gutta-percha points. • Materials surface characteristics were assessed using quantitative backscattered electron imaging, reference point indentation, and contact angle analyzer. • The most significant differences in mineralization, indentation, and adhesive outcomes were observed after ethylenediaminetetraacetic acid treatment. • Irrigation solutions confer to superior sealing ability of endodontic filling materials. • Micromechanical characteristics of dentine after irrigation are considerable reduced. - Abstract: The objective of this study was to determine the effects of various irrigation solutions on root canal dentine and gutta-percha surface properties. In addition, the effects of disinfectant chemicals on the wettability and surface morphological properties of the filling materials were evaluated. Ethylenediaminetetraacetic acid (EDTA), citric acid, and ozone were employed as irrigation solutions for dentine and gutta-percha treatment. Thereafter, the samples’ microstructure, degree of mineralization, and mechanical properties were assessed by means of quantitative backscattered electron imaging (qBEI) and reference point indentation (RPI). A contact angle analyzer was used to measure adhesion on the tested materials. Here, EDTA had the most significant affect on both the mechanical properties and the adhesive behavior of dentine. Citric acid did not affect dentine wettability, whereas the indentation properties and the mineralization were reduced. Similar effects were observed when ozone was used. The dentinal tubules were significantly widened in citric acid compared to the ozone group. EDTA causes considerable micromechanical surface alteration of dentine and gutta-percha, but represents the best option in clinical cases where a high adhesiveness of the filling materials is desired.

  6. Evaluation of a new nickel-titanium system to create the glide path in root canal preparation of curved canals.

    Science.gov (United States)

    D'Amario, Maurizio; Baldi, Mario; Petricca, Roberto; De Angelis, Francesco; El Abed, Rashid; D'Arcangelo, Camillo

    2013-12-01

    Nickel-titanium rotary instruments recently have been introduced with the purpose of creating an initial glide path. The purpose of this study was to compare the maintenance of canal anatomy, the occurrence of apical transportation, and the working time observed using mechanised instrumentation with the new G-File rotary system (Micro-Mega, Besançon Cedex, France) with those observed using instrumentation with the PathFile system (Dentsply Maillefer, Ballaigues, Switzerland) and manual instrumentation with K-type files (Micro-Mega) to create a glide path in curved root canals. The mesial canals of 45 mandibular molars (with curvature angles between 25° and 35°) were selected. The specimens were randomly divided into 3 groups with 15 canals each, and canal preparations were performed by an endodontist using #12-17 G-File rotary instruments (group GF), #13-16-19 PathFile rotary instruments (group PF), and #10-15-20 K-type stainless steel manual files (group M). A digital double radiographic technique was used to determine apical transportation and the change in the angle of curvature. The working time was also calculated. No statistically significant differences in the angle of canal curvature and apical transportation were found between the groups. However, concerning the working time, specimens from the group who underwent canal preparation using #12-17 G-File rotary instruments achieved significantly lower mean values when compared with the other 2 groups, whereas the group who underwent canal preparation using the #10-15-20 K-type stainless steel manual files had the highest values. The G-File rotary instruments, the PathFile system, and the manual instruments did not have any influence on the occurrence of apical transportation nor did they produce a change in the angle of canal curvature. The G-File instruments seemed to be the most rapid system in creating a safe glide path. Copyright © 2013 American Association of Endodontists. Published by Elsevier Inc

  7. El proceso constructivo de los teatros del "Canal" del arquitecto Juan Navarro Baldeweg

    Directory of Open Access Journals (Sweden)

    del Aguila García, Alfonso

    2008-03-01

    Full Text Available This present article studies and chriticizes the building system and the developement of the theater and dance complex of Canal (Teatros del Canal, Madrid, designed by Juan Navarro Baldeweg, Principal Professor of Architectural Design at Madrid School of Architecture Polytechnic University. These theaters are being built in the center of Madrid city. The owner and developer of this complex is Canal de Isabel II (the water supply company of Madrid regional Government. The project consist in a three building complex, two theatres and a choreographic centre, put together by a back service block, each of them with it’s own different building solutions. This article is the result of the work done during the term 2006-07 of the Seminar of "Industrialization of Building Process" that, under the direction of the Principal Professor Alfonso del Águila, takes place within the Ph. D. Program of the Department of Construction and Architectural Technology set in Madrid School of Architecture Polytechnic University. The work includes two different parts: the fi rst one, which introduces is a prologue written by Prof. Navarro and a general description of the building. The second part describes its different construction areas, ranging from the different structural solutions, the hung façades pretending to be theatre curtains, some aspects of the interior design, as acoustics, special furniture and fi nishes, not in a mere descriptive way, but also from a critical manner with the intention to be a consequence with didactical value for the students/ authors.El artículo que se presenta estudia y valora el sistema constructivo, y su desarrollo, de las obras de los Teatros del Canal, obra del Catedrático de Proyectos de la Escuela de Arquitectura de Madrid, Prof. Navarro Baldeweg, que se están llevando a cabo en Madrid, siendo la Promotora y Propietaria el Canal de Isabel II de la Comunidad Autónoma de Madrid. Se trata de un conjunto de tres edifi cios

  8. SIMULACIÓN ESTACIONARIA DE UN EVAPORADOR DE DOBLE EFECTO PARA JUGO DE TOMATE

    Directory of Open Access Journals (Sweden)

    Álvaro Núñez

    2012-01-01

    Full Text Available En este trabajo se desarrolló un modelo estacionario para simular un sistema evaporador de doble efecto destinado a la concentración de jugo de tomate. Debido a que el licopeno muestra capacidad antioxidante, es deseable que su concentración sea máxima en la pasta de tomate. Ello se logra optimizando tanto el diseño como las condiciones de operación del equipo concentrador de jugo. Para alcanzar ese objetivo, se incorporó al modelo la cinética de degradación del licopeno, y se realizó un estudio de sensibilidad para determinar las relaciones que vinculan las variables de proceso. El estudio determinó que el contenido de licopeno en el producto es altamente sensible al tiempo de residencia; mientras que el consumo de vapor está determinado por la presión del vapor de servicio y las presiones de los efectos.

  9. VAPD-2D: Simulador para Apoio ao Ensino de Engenharia Ambiental

    Directory of Open Access Journals (Sweden)

    Carlos Vitor de Alencar Carvalho

    2015-07-01

    Full Text Available Este trabalho apresenta o desenvolvimento de um software educativo, chamado VAPD-2D para apoio às soluções para problemas da Engenharia Ambiental, mais especificamente de problemas onde o transporte por difusão é predominante. O mecanismo de transporte por difusão tem várias aplicações práticas na Engenharia, destacando os estudos da contaminação do solo e de águas subterrâneas por produtos químicos orgânicos e inorgânicos. Estes estudos envolvem, basicamente, a determinação dos parâmetros físicos e químicos dos contaminantes e a forma como estes se movem, quando dissolvidos na água subterrânea. O VAPD-2D é um simulador numérico de interface bastante simples que permite aos estudantes da Engenharia simular e testar parâmetros para diversos tipos de problemas.

  10. Simulación de una red Grid con máquinas virtuales para crear un entorno de aprendizaje de la computación de alto desempeño

    OpenAIRE

    Edwin Eduardo Millán-Rojas; Adriana Patricia Gallego-Torres; Diana Carolina Chico-Vargas

    2016-01-01

    Presenta una metodología de construcción de una plataforma para simular una red Grid con máquinas virtuales, con el objetivo de crear entornos virtuales que contribuyan a los procesos de aprendizaje. El diseño utilizado para el desarrollo está basado en un prototipo que contribuye a generar un entorno de simulación de bajo costo a través de la computación de alto desempeño. Como resultado de la investigación se obtuvo un conjunto de máquinas virtuales que pueden ser desplegadas en cualquier e...

  11. Temporal Bone Fracture Causing Superior Semicircular Canal Dehiscence

    Directory of Open Access Journals (Sweden)

    Kevin A. Peng

    2014-01-01

    Full Text Available Importance. Superior semicircular canal dehiscence (SCD is a third window lesion of the inner ear causing symptoms of vertigo, autophony, tinnitus, and hearing loss. A “two-hit” hypothesis has traditionally been proposed, whereby thinly developed bone overlying the superior canal is disrupted by a sudden change in intracranial pressure. Although the symptoms of SCD may be precipitated by head injury, no previous reports have described a temporal bone fracture directly causing SCD. Observations. Two patients sustained temporal bone fractures after closed head trauma, and developed unilateral otologic symptoms consistent with SCD. In each instance, computed tomography imaging revealed fractures extending through the bony roof of the superior semicircular canal. Conclusions and Relevance. Temporal bone fractures, which are largely treated nonoperatively, have not previously been reported to cause SCD. As it is a potentially treatable entity, SCD resulting from temporal bone fracture must be recognized as a possibility and diagnosed promptly if present.

  12. [Benign postural vertigo and nystagmus of the horizontal semicircular canal].

    Science.gov (United States)

    Waespe, W

    1997-02-22

    Benign paroxysmal vertigo and nystagmus are induced not only by the posterior but also by the horizontal semicircular canal. Benign positional nystagmus of the horizontal canal is more often observed than was previously thought. In 10 patients we analyzed the characteristics and the variability of nystagmus which accompanies positional vertigo of the horizontal canal. There are two forms of nystagmus: primary-geotropic, most often paroxysmal nystagmus (7 patients), and primary-apogeotropic, non-paroxysmal nystagmus (3 patients). Interestingly, in 2 patients with the primary-apogeotropic form the nystagmus converted during the examination into the primary-geotropic form. The reverse was not observed. We discuss the possible pathophysiological mechanisms which could be relevant for provoking manoeuvres.

  13. Tullio phenomenon in superior semicircular canal dehiscence syndrome.

    Science.gov (United States)

    Basura, Gregory J; Cronin, Scott J; Heidenreich, Katherine D

    2014-03-18

    Tullio phenomenon refers to eye movements induced by sound.(1) This unusual examination finding may be seen in superior semicircular canal dehiscence (SSCD) syndrome.(2) This disorder is due to absent bone over the superior semicircular canal (figure). Patients complain of dizziness triggered by loud sound, aural fullness, autophony, and pulsatile tinnitus. When Tullio phenomenon exists in SSCD syndrome, the patient develops a mixed vertical-torsional nystagmus in which the slow phase rotates up and away from the affected ear (video on the Neurology® Web site at Neurology.org). This pattern of nystagmus aligns in the plane of the dehiscent semicircular canal and is due to excitation of its afferent nerves.

  14. Application of Different Algorithms to Optimal Design of Canal Sections

    Directory of Open Access Journals (Sweden)

    A. Kentli

    2014-08-01

    Full Text Available Today the increased world population and therefore the growth demand has forced the researchers to investigate better water canal networks distributing much more water while at least keeping its quality. Canal design formulas are explicitly obtained for different cross-sections considering minimum area but optimal design of canal sections considering seepage and evaporation losses are still an open area to study. In this study, two different algorithms are applied to this problem and results are compared with the one in literature. Genetic algorithm and sequential quadratic programming technique are used in optimization. Triangular, rectangular and trapezoidal cross-sections are optimized. It is seen that both algorithms are giving more accurate results than in literature.

  15. Commentaires sur la valeur piscicole du Canal de Roubaix (Nord

    Directory of Open Access Journals (Sweden)

    ARRIGNON J.

    1970-10-01

    Full Text Available La population piscicole du Canal de ROUBAIX a été inventoriée par pêche électrique. Trois passages, suivis chacun de l'enlèvement des poissons capturés, ont été opérés dans chacun des trois Secteurs d'inventaire. Le peuplement le plus probable ainsi estimé (par la méthode De Lury,est en rapport avec le degré de pollution du canal. On constate aussi queles poissons se cantonnent le long des berges, sur une largeur de 2 à 3mètres.L'estimation à l'hectare représente donc en réalité le stock d'une zone n'ayant que 25 % de la surface totale du Canal. Les poissons contrôlés sont pour la plupart des poissons de repeuplement.

  16. Morphological examination of the obturator notch and canal in Cervidae.

    Science.gov (United States)

    Tae, Hyun-Jin; Park, Byung-Yong; Kim, In-Shik; Ahn, Dongchoon

    2014-05-01

    The purpose of this study was to investigate gross findings of the obturator notch (ON) and obturator canal (OC) in Cervidae. A total of 183 pelvic girdles from 26 species of deer were examined, and the obturator canal (OC) was classified into 4 types based on the degree of separation from the obturator foramen (OF). The deep ON was observed primarily in the subfamily Capreolinae (telemetacarpal deer). The small bony OC was frequently observed in Hydropotes inermis, Mazama gouazoubira and Ozotoceros bezoarticus. A canal without a tubercle or bony bridge structure was mainly observed in the subfamily Cervinae (plesiometacarpal deer). These results suggest that the deep ONs or the OCs separated by bony structures are more common in telemetacarpal rather than plesiometacarpal deer.

  17. A RARE CASE OF HYDROCOELE OF CANAL OF NUCK

    Directory of Open Access Journals (Sweden)

    Abhishek Kumar

    2016-02-01

    Full Text Available INTRODUCTION Hydrocele of canal of Nuck of female is a rare developmental disorder corresponding to the hydrocele of the spermatic cord of males It results from the failure of obliteration of the distal portion of evaginated parietal peritoneum within the inguinal canal which forms a sac containing fluid. It can be diagnosed on the operating table at the time of operation of suspected incarcerated inguinal hernia. We present a rare case of a 15 year old girl with right-sided groin swelling over 4 years, diagnosed as hydrocele of canal of Nuck. Patient underwent surgical exploration and excision of hydrocele. This entity should be considered in young females presenting with an inguinal swelling.

  18. Microbiological indicators of water quality in the Xochimilco canals, Mexico City Indicadores microbiológicos de la calidad del agua de los canales de Xochimilco de la Ciudad de México

    Directory of Open Access Journals (Sweden)

    Luis Alfredo Juárez-Figueroa

    2003-10-01

    efectuado en Xochimilco, México. Durante noviembre y diciembre de 2001 se muestrearon 10 sitios, cinco efluentes y cinco canales, para la cuantificación de coliformes fecales y enterococos (filtración en membrana de nitrocelulosa, colifagos somáticos (técnica de doble capa de agar, ooquistes de Cryptosporidium sp. y quistes de Giardia sp. (concentración en filtros Envirocheck y microscopía de inmunofluorescencia. Se efectuó comparación de los promedios de las cuentas de organismos hallados, en efluentes y canales, mediante t de Student. RESULTADOS: El agua tratada que descarga en los canales mostró cantidades bajas de coliformes fecales (media de 40.4/100 ml, enterococos (media de 58.8/100 ml y quistes de Cryptosporidium (media de 13.2/100 l, mientras que los colifagos y quistes de Giardia estuvieron presentes en gran cantidad (media de 1467.5/100 ml y 1199.8/100 l, respectivamente, sugiriendo que el tratamiento del agua puede ser ineficaz para remover estos agentes. En los canales de irrigación de vegetales se encontró una cantidad significativamente menor de quistes de Giardia (media de 45/100 l y no se encontraron ooquistes de Cryptosporidium, lo que sugiere la remoción natural de estos agentes. Algunos aislamientos de E coli obtenidos de un canal contaminado con descargas cloacales mostraron una multirresistencia a antibióticos que fue transferida por conjugación a otras bacterias mediante plásmidos. Esto sugiere la posible diseminación de la resistencia a bacterias del medio (posibles patógenas. Existen numerosos asentamientos humanos cercanos a las chinampas que descargan desechos directamente a los canales. CONCLUSIONES: La implantación de métodos de tratamiento de excretas que resulten costeables y culturalmente aceptables debe realizarse mediante una cuidadosa planeación y consulta, si estos métodos han de ser adoptados y sostenidos por la población local.

  19. Contenido y audiencia de los informativos: Canal Sur TV y TVE en Andalucía

    Directory of Open Access Journals (Sweden)

    Dr. Carlos A. Guerrero Serón

    1999-01-01

    Full Text Available En este artículo sintetizo los resultados de una investigación que, financiada por el Grupo de Investigación «Desarrollo y Cambio Socioeconómico», tuvo como objetivo conocer la influencia política en los contenidos de los informativos. Para realizar el contraste se analizaron los informativos de Canal Sur y las desconexiones informativas de Televisión Española, TVE-Andalucía en la consideración de que, en estos momentos, se da una situación idónea para poner a prueba la hipótesis habida cuenta que conviven dos televisiones públicas, la andaluza, controlada por el Partido Socialista, y la nacional, bajo el control del Partido Popular. Los resultados del análisis de contenido se cotejaron con los perfiles respectivos de sus audiencias y con los generales de la franja horaria, para comprobar si la audiencia específica se aparta sensiblemente de la tipología general del periodo horario y, en su caso, si la selección de los valores noticia por parte de los emisores -periodistas- están en disonancia con lo que el público espera.

  20. blood in the canal space of the teeth

    Directory of Open Access Journals (Sweden)

    Ali Soleymani

    2014-03-01

    Full Text Available Introduction: Apical seal in blood or dry root canal is a problem in endodontic treatment. Failure of apical seal causes inflammatory reaction and failure root canal treatment. Because of the sealer properties, root canal should be dry for obturation. But hydrophilic sealers can adhere to root canal walls nowadays and this problem is still controversial. This study aimed at determining the apical microleakage of AH26 and MTA Fillapex sealers in dry and bloody condition. Methods: This experimental in vitro study was done on 48 extracted central teeth. The researchers used the Mtwo rotary files for root canal instrumentation. In this process, the teeth were divided into four groups (2 dry groups and 2 bloody groups and two groups as positive and negative control (each group of 4 teeth. All sealers were prepared according to the factory instruction and the obturation was done with gutta-percha and sealer. After 7 days in 100% moisture condition, the teeth were placed in the ink for 3 days and then were cut across longitudinal axis and the level of microleakage was measured by stereomicroscope.Finally, the data were analyzed by SPSS software, ANOVA, Chi-Square and t-test statistical tests. Results:The mean of MTA Fillapex and AH26 apical microleakage in blood groups were (448.61± 34.67 Mm and (429.84± 31.63 Mm respectively. The minimum microleakage belonged to AH26 sealer, but it was not significant. Conclusion: AH26 sealer is a better barrier against microleakage in comparison with MTA Fillapx, although it is not significant. Also, the evidence suggests drying the canal leads to a better apical seal and the blood significantly increases apical microleakage. 

  1. Facial nerve canal dehiscence in chronic otitis media without cholesteatoma.

    Science.gov (United States)

    Nomiya, Shigenobu; Kariya, Shin; Nomiya, Rie; Morita, Norimasa; Nishizaki, Kazunori; Paparella, Michael M; Cureoglu, Sebahattin

    2014-03-01

    The information on incidence of the facial nerve canal dehiscence in chronic otitis media is important for surgeons. The purpose of this study is to disclose the histopathologic findings of facial nerve canal dehiscence in human temporal bones with chronic otitis media. We divided the human temporal bones into two groups (age 4 years, and under 4 years of age). We evaluated the incidence and the area of the facial nerve canal dehiscence in chronic otitis media under light microscopy. Age-matched normal control temporal bones were also examined. In the age group of 4 years, 68.9 % of temporal bones with chronic otitis media and 71.9 % of controls had the facial nerve canal dehiscence. There was no significant difference between them (P = 0.61). The area of the dehiscence in temporal bones with chronic otitis media was not statistically different from controls (P = 0.53). In the age group under 4 years, 88.2 % of temporal bones with chronic otitis media and 76.5 % of controls had the dehiscence. No significant difference was found between them (P = 0.66). The area of the dehiscence in temporal bones with chronic otitis media was not statistically different from controls in the age group under 4 years (P = 0.43). In chronic otitis media, the incidence of facial nerve canal dehiscence was high and was not statistically different from controls. These results suggest that there is no association between chronic otitis media and the presence of facial nerve canal dehiscence.

  2. Ligament structures in the tarsal sinus and canal.

    Science.gov (United States)

    Li, Shu-Yuan; Hou, Zhi-Dian; Zhang, Peng; Li, Hong-Liang; Ding, Zi-Hai; Liu, Yu-Jie

    2013-12-01

    The concrete anatomy and functional characteristics of the subtalar ligaments have been a matter of debate that some believe has hampered the progress of clinical ligament reconstruction. In 32 fresh-frozen cadaver feet, the course of the inferior extensor retinaculum (IER) and other subtalar ligaments was carefully measured and photographed both from the portal of the tarsal sinus and from a posterior view. The IER inserted inside the tarsal sinus and canal by means of 3 roots: a lateral, an intermediate, and a medial one. These roots, along with the tarsal canal, divided the subtalar space into 3 parts. In front of the IER and inside the tarsal sinus, the thick cervical ligament (CL) lay at a 45-degree angle to the calcaneus. Behind the IER and inside the posterior capsule, in most cases (25 of 32 specimens), the posterior capsular ligament (PCaL) lay directly in front of the posterior talocalcaneal facet. Inside the tarsal canal, the fan-shaped medial root of the IER spread from outside upper lateral to lower medial, and the interosseous talocalcaneal ligament (ITCL) ran from upper medial to lower lateral; fibers of these 2 ligaments blended tightly together to form a V-shaped ligament complex. Just anterior to this complex in some cases (20 of 32 specimens), a short narrow upright ligament, the tarsal canal ligament (TCL), was located behind the middle talocalcaneal joint. The results of this study show that the CL is the primary ligament in the tarsal sinus and that the ITCL is a thin single band rather than a strong bilaminar ligament located inside the tarsal canal. Instead, the medial root of the IER is the primary ligamentous structure in the tarsal canal. The anatomical description provided here may provide a more accurate theoretical foundation for clinical subtalar stability restoration.

  3. Root Canal Treatment for Deciduous Teeth: A Review

    Directory of Open Access Journals (Sweden)

    Müge Daloğlu

    2017-08-01

    Full Text Available The early loss of deciduous teeth leads to many negations in terms of physiological, functional and aesthetic. The structure of the deciduous teeth causes decay to progress much easier and less time and this is the need for frequent dental pulp treatment to be kept in the mouth. The new materials that will increase the success of deciduous teeth root canal treatment are continuing to investigate. In this study, it is aimed that recently prominent current approaches are to be compiled in root canal treatment of deciduous teeth.

  4. Mesiodens Within the Nasopalatine Canal: An Exceptional Entity.

    Science.gov (United States)

    Aoun, Georges; Nasseh, Ibrahim

    2016-10-24

    A supernumerary tooth is one that is supplementary to the normal dentition. It can be found anywhere at the dental arch. A mesiodens is a supernumerary tooth located between the two maxillary central incisors usually palatally or within the alveolar process. Less frequently, the mesiodens is in relation with the nasal floor and the nasopalatine canal walls. This paper presents a very rare case of an impacted inverted mesiodens located inside the nasopalatine canal and found incidentally with a cone-beam computed tomography examination.

  5. Mesiodens within the nasopalatine canal: an exceptional entity

    Directory of Open Access Journals (Sweden)

    Georges Aoun

    2016-12-01

    Full Text Available A supernumerary tooth is one that is supplementary to the normal dentition. It can be found anywhere at the dental arch. A mesiodens is a supernumerary tooth located between the two maxillary central incisors usually palatally or within the alveolar process. Less frequently, the mesiodens is in relation with the nasal floor and the nasopalatine canal walls. This paper presents a very rare case of an impacted inverted mesiodens located inside the nasopalatine canal and found incidentally with a cone-beam computed tomography examination.

  6. Agrandamiento gingival por bloqueantes de canales de calcio

    OpenAIRE

    Ocaña Diestra, Tania; Facultad de Odontología, Universidad Nacional Mayor de San Marcos, Perú; García Linares, Sixto; Departamento Académico Médico Quirúrgico, Facultad de Odontología, Universidad Nacional Mayor de San Marcos, Perú

    2014-01-01

    Objetivo: Determinar la frecuencia del agrandamiento gingival en pacientes hipertensos que consumen fármacos bloqueantes de canales de calcio y compararlo con otro grupo de pacientes hipertensos que no consumen dichos fármacos. Métodos: En el estudio descriptivo transversal se evaluaron a 50 pacientes hipertensos que consumían bloqueantes de canales de calcio (grupo de estudio) y a 50 pacientes hipertensos que recibían tratamiento con otro tipo de antihipertensivos (grupo control). Se les rea...

  7. Optimal volume of local anaesthetic for the adductor canal block

    DEFF Research Database (Denmark)

    Jæger, P.; Jenstrup, M. T.; Lund, J.

    2015-01-01

    theED95. Distal filling of the adductor canal was assessed by magnetic resonance imaging (primary outcome). Secondary outcomeswere the effect of volume on proximal spread to the femoral triangle (also assessed by magnetic resonance imaging), quadricepsmuscle weakness (decrease by ≥25% from baseline......, respectively (P=0.25). Seven subjects had a reduction in muscle strength, but there was no difference betweengroups (P=0.85). Conclusions: For an ACB, the dose closest to the ED95 needed to fill the adductor canal distally was 20 ml. There was nosignificant correlation between volume and proximal spread...... or muscle strength.Clinical trial registration: NCT02033356....

  8. Shape and Deformation Analysis of the Human Ear Canal

    DEFF Research Database (Denmark)

    Darkner, Sune

    is on the extraction and analysis of the shape and deformation of the ear canal due to movements of the mandible, leaning over, and turning of the head. Methods for surface registration with focus on non-rigid registration are presented, as well as a wide range of statistical methods used for analyzing the shapes...... and deformation fields. The results show that the ear canal changes shape significantly in all subjects and that the deformation is more complicated than previously described in the literature. It is shown that the deformation at specific locations in the ear is significantly correlated to comfort issues reported...

  9. Root canal obturation of primary teeth: Disposable injection technique

    Directory of Open Access Journals (Sweden)

    S K Bhandari

    2012-01-01

    Full Text Available The aim of the study was to outline a simple, cost-effective technique for obturation of primary tooth root canals. A total of 75 primary teeth were treated in 52 subjects by the technique discussed, i.e. injecting plastic flowable material into the root canals after desired preparation, using disposable needle and syringe. All the patients were followed up for 3 years and 6 months, with no clinical or radiologic evidence of pathology or need for untimely extraction. In conclusion, the technique described is simple, economical, can be used with almost all filling materials used for the purpose, and is easy to master with minimal chances of failure.

  10. A Guyon's canal ganglion presenting as occupational overuse syndrome: A case report.

    LENUS (Irish Health Repository)

    Chan, Jeffrey C Y

    2008-01-01

    Occupational overuse syndrome (OOS) can present as Guyon\\'s canal syndrome in computer keyboard users. We report a case of Guyon\\'s canal syndrome caused by a ganglion in a computer user that was misdiagnosed as OOS.

  11. Root Canal Stripping: Malpractice or Common Procedural Accident-An Ethical Dilemma in Endodontics

    National Research Council Canada - National Science Library

    Ciobanu, Ionela Elisabeta; Rusu, Darian; Stratul, Stefan-Ioan; Didilescu, Andreea Cristina; Cristache, Corina Marilena

    2016-01-01

    Root canal stripping is defined as an oblong, vertical perforation that appears especially in the middle section of curved root canals during endodontic treatments with nickel-titanium (Ni-Ti) instruments...

  12. AFSC/ABL: Lynn Canal Overwinter Acoustic Survey, 2004-2005

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The acoustic trawl database for Lynn Canals echo-trawl survey was conducted from 2001 to 2004 throughout southern Lynn Canal in southeast Alaska. Acoustic surveys...

  13. AFSC/ABL: Lynn Canal Echo-Integrated Trawl Surveys, 2001-2004

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The acoustic trawl database for Lynn Canals echo-trawl survey was conducted from 2001 to 2004 throughout southern Lynn Canal in southeast Alaska. Acoustic surveys...

  14. Evaluation of Mandibular Anterior Nutrient Canals in Periodontal Diseases: A Prospective Case Control Radiographic Study

    Directory of Open Access Journals (Sweden)

    Govind Singh

    2011-01-01

    Conclusions: The prevalence of nutrient canals was higher in patients with periodontitis. As age advanced, prevalence was more. Increased frequency of nutrient canals of 3 or more than 3 was seen with increased seventy of bone loss.

  15. Development of the lateral line canal system through a bone remodeling process in zebrafish.

    Science.gov (United States)

    Wada, Hironori; Iwasaki, Miki; Kawakami, Koichi

    2014-08-01

    The lateral line system of teleost fish is composed of mechanosensory receptors (neuromasts), comprising superficial receptors and others embedded in canals running under the skin. Canal diameter and size of the canal neuromasts are correlated with increasing body size, thus providing a very simple system to investigate mechanisms underlying the coordination between organ growth and body size. Here, we examine the development of the trunk lateral line canal system in zebrafish. We demonstrated that trunk canals originate from scales through a bone remodeling process, which we suggest is essential for the normal growth of canals and canal neuromasts. Moreover, we found that lateral line cells are required for the formation of canals, suggesting the existence of mutual interactions between the sensory system and surrounding connective tissues. Copyright © 2014 Elsevier Inc. All rights reserved.

  16. Morphology of the mandibular canal and the angulation between the mandibular and mental canals in dry skulls

    DEFF Research Database (Denmark)

    Pálsson, S R; Kjaer, I

    2008-01-01

    The aim of this study was to analyse the correlation between external and internal mandibular morphology in adult or adolescent normal anthropological mandibles. Lateral radiographs of 31 symmetrical mandibles were analysed. The external morphology was defined by the gonial and beta-angles....... In order to analyse internal morphology, a metallic pin was placed in the mental canal on the left side before radiography. The angle between the mental and the mandibular canals was termed the 'mental angle' and that expressing the curvature of the mandibular canal, the 'mandibular angle'. Spearman...... correlation analysis was used to investigate the relationships between the angles. Internal morphology: a statistically significant correlation was found between the mental and mandibular angles (correlation coefficient: -0.60, P=0.0004). When the mental angle was narrow, the mandibular angle tended...

  17. Gaussian plume model for the SO{sub 2} in a thermoelectric power plant; Modelo de pluma gaussiano para el SO{sub 2} en una central termoelectrica

    Energy Technology Data Exchange (ETDEWEB)

    Reyes L, C.; Munoz Ledo, C. R. [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

    1992-12-31

    The Gaussian Plume Model is an analytical extension to simulate the dispersion of the SO{sub 2} concentration at ground level as a function of the emission changes in the spot sources, as well as the pollutant dispersion in the Wind Rose, when the necessary parameters are fed. The model was elaborated in a personal computer and the results produced are generated in text form. [Espanol] El modelo de pluma gaussiano es una extension analitica para simular la dispersion de las concentraciones de SO{sub 2} a nivel del piso en funcion de los cambios de las emisiones en las fuentes puntuales, asi como, la dispersion del contaminante en la rosa de los vientos cuando se le alimentan los parametros necesarios. El modelo fue elaborado en una computadora personal y los resultados que proporciona los genera en modo texto.

  18. Aproximación en diferencias finitas a la ecuación de Richards para transporte de agua en suelos no saturados

    OpenAIRE

    Martinez, José Luis; Schvezov, Carlos Enrique; Rosenberger, Mario Roberto

    2016-01-01

    Se desarrolló y validó un modelo matemático unidimensional para simular el flujo vertical del agua en suelo no saturado. El modelo utiliza la ecuación diferencial parcial de Richards que gobierna el movimiento del agua en suelo, expresada en términos del potencial matricial (capacidad de absorción de agua) como función de la profundidad y el tiempo. Debido a la dificultad de obtener solución analítica de esta ecuación, los métodos numéricos aparecen como la herramienta más eficiente. En la ap...

  19. Indicadores microbiológicos de la calidad del agua de los canales de Xochimilco de la Ciudad de México

    Directory of Open Access Journals (Sweden)

    Juárez-Figueroa Luis Alfredo

    2003-01-01

    Full Text Available OBJETIVO: Cuantificar diversos indicadores de contaminación fecal en los efluentes de dos plantas de tratamiento de aguas residuales y en muestras recogidas en varios canales de Xochimilco. MATERIAL Y MÉTODOS: Estudio transversal efectuado en Xochimilco, México. Durante noviembre y diciembre de 2001 se muestrearon 10 sitios, cinco efluentes y cinco canales, para la cuantificación de coliformes fecales y enterococos (filtración en membrana de nitrocelulosa, colifagos somáticos (técnica de doble capa de agar, ooquistes de Cryptosporidium sp. y quistes de Giardia sp. (concentración en filtros Envirocheck y microscopía de inmunofluorescencia. Se efectuó comparación de los promedios de las cuentas de organismos hallados, en efluentes y canales, mediante t de Student. RESULTADOS: El agua tratada que descarga en los canales mostró cantidades bajas de coliformes fecales (media de 40.4/100 ml, enterococos (media de 58.8/100 ml y quistes de Cryptosporidium (media de 13.2/100 l, mientras que los colifagos y quistes de Giardia estuvieron presentes en gran cantidad (media de 1467.5/100 ml y 1199.8/100 l, respectivamente, sugiriendo que el tratamiento del agua puede ser ineficaz para remover estos agentes. En los canales de irrigación de vegetales se encontró una cantidad significativamente menor de quistes de Giardia (media de 45/100 l y no se encontraron ooquistes de Cryptosporidium, lo que sugiere la remoción natural de estos agentes. Algunos aislamientos de E coli obtenidos de un canal contaminado con descargas cloacales mostraron una multirresistencia a antibióticos que fue transferida por conjugación a otras bacterias mediante plásmidos. Esto sugiere la posible diseminación de la resistencia a bacterias del medio (posibles patógenas. Existen numerosos asentamientos humanos cercanos a las chinampas que descargan desechos directamente a los canales. CONCLUSIONES: La implantación de métodos de tratamiento de excretas que resulten

  20. Maxillary first molars with six canals confirmed with the aid of cone-beam computed tomography

    Directory of Open Access Journals (Sweden)

    Tahra Mohammad Al-Habboubi

    2016-01-01

    Full Text Available The maxillary first molar exhibits unpredictable root canal morphology. Different number of root canals has been reported with the aids of new tools. It is very important to clinically detect all canals for better outcome results. The purpose of the present case is to present a case of the maxillary first molar in a Saudi male patient with an anatomical variation of having six root canals that were confirmed with cone-beam computed tomography.

  1. Macroanatomic and radiologic characteristics of the superior genial spinal foramen and its bony canal

    OpenAIRE

    Vandewalle, Giovani; Liang, Xin; JACOBS, Romain; Lambrichts, Ivo

    2006-01-01

    Purpose: To determine the incidence, size, location, course, and content of the superior genial spinal foramen and its bony canal. Materials and Methods: Three hundred eighty dry human cadaver mandibles were morphometrically analyzed by measuring the distance from the foramen to the mandibular base and the size of the foramen and bony canal. Radiologically, the course of the bony canal and its relation to the mandibular incisive canal were investigated after injecting contrast medium (Omnipaq...

  2. Extracting Environmental Benefits from a New Canal in Nicaragua: Lessons from Panama.

    Science.gov (United States)

    Condit, Richard

    2015-07-01

    Biologists have raised objections to a new canal in Nicaragua, but in this Essay I argue that dire predictions of environmental catastrophe are exaggerated. I present an alternative view based on my research experience in Panama, where Canal operations foster forest conservation. Currently in Nicaragua, the rate of forest loss is so rapid that the canal cannot make it worse. Rather, I contend, adoption of international standards in canal construction could lead to net environmental and social benefits for the country.

  3. Kedo-S Paediatric Rotary Files for Root Canal Preparation in Primary Teeth – Case Report

    OpenAIRE

    Jeevanandan, Ganesh

    2017-01-01

    Nickel-Titanium (Ni-Ti) instrument are widely used for root canal preparation in permanent tooth compared to primary teeth. Hand instrumentation technique remains the conventional method for root canal preparation in primary teeth. The time taken for root canal preparation with the conventional method is more resulting in patients and clinicians fatigue. Recently Ni-Ti rotary files designed for permanent tooth has been used for root canal preparation in primary teeth. Using rotary instruments...

  4. Five Root Canals for a Maxillary First Molar Tooth – A Case Report

    OpenAIRE

    Mohammad Aminul Islam; Md. Shamsul Alam

    2012-01-01

    This case report represents assessment and management of a maxillary left first molar tooth containing five root canals by endodontic treatment. In this case Mesiobuccal 2 (MB2), Mesiopalatal (MP) and Distobuccal (DB) canals were missed as well as very poor obturation at palatal and mesiobuccal1(MB1) canal during previous treatment history. Three mesiobuccal (MB1, MB2, and MP), DB and palatal canals were identified and endodontic retreatment was done followed by final restoration. This case p...

  5. Independent and Confluent Middle Mesial Root Canals in Mandibular First Molars: A Report of Four Cases

    Directory of Open Access Journals (Sweden)

    Mohanavelu Deepalakshmi

    2012-01-01

    Full Text Available Mandibular molars demonstrate considerable variations with respect to number of roots and root canals. The possibility of additional root canals should be considered even in teeth with a low frequency of abnormal root canal anatomy. This paper discusses the endodontic management of the rare anatomical complexity middle mesial canals in mandibular first molar and also serves to remind the clinicians that such anatomical variations should be taken into account during the endodontic treatment of the mandibular molars.

  6. Retrieval of a metallic obstruction from the root canal of a premolar using Masserann technique

    OpenAIRE

    Vivekananda Pai, A R; Mir, Shugufta; Jain, Rachit

    2013-01-01

    A metallic obstruction in the root canal blocks canal cleaning and shaping procedures and requires either bypassing or retrieval. Many methods have been recommended to retrieve a metallic obstruction from the root canal. This article describes the retrieval of a metallic obstruction from the root canal of a premolar using Masserann technique to facilitate endodontic retreatment. Masserann technique is said to have limited application in posteriors. However, in this case, the obstruction was s...

  7. The revised anatomy of the canals connecting the orbit with the cranial cavity.

    Science.gov (United States)

    Regoli, Marì; Bertelli, Eugenio

    2017-04-01

    Orbits are connected with the middle cranial fossa via the optic canal, the superior orbital fissure, the M-type orbitomeningeal foramen, the metoptic canal, an accessory anterior opening of the foramen rotundum, and Warwick's canal. They are also in communication with the anterior cranial fossa via the ethmoidal canals and the A-type orbitomeningeal foramen. The anatomy of these conduits has been recently enriched with several details that are summarized and reviewed in this article.

  8. Funciones de los canales iónicos CFTR y ENAC en la fibrosis quística

    Directory of Open Access Journals (Sweden)

    Alejandra G. Palma

    2014-04-01

    Full Text Available La fibrosis quística se debe a la ausencia o defecto del canal transmembrana regulador de la fibrosis quística (CFTR, un canal de cloruro codificado en el gen cftr que juega un papel clave en la homeostasis del agua e iones. El CFTR es activado por el AMPc y se localiza en las membranas apicales y basolaterales de las vías aéreas, intestino y glándulas exocrinas. Una de sus funciones primarias en los pulmones es mantener la capa de líquido superficial a través de su función de canal y regular el canal epitelial de sodio sensible al amiloride (ENaC. Se han identificado más de 1900 mutaciones en el gen cftr. La enfermedad se caracteriza por secreciones viscosas en las glándulas exocrinas y por niveles elevados de cloruro de sodio en el sudor. En la fibrosis quística el CFTR no funciona y el ENaC está desregulado; el resultado es un aumento en la reabsorción de sodio y agua con la formación de un líquido viscoso. En las glándulas sudoríparas tanto el Na+ como el Cl- se retienen en el lumen causando una pérdida de electrolitos durante la sudoración y el NaCl se elimina al sudor. Así, los niveles elevados de NaCl son la base del test del sudor inducido por pilocarpina, un método de diagnóstico para la enfermedad. En esta revisión se discuten los movimientos de Cl- y Na+ en las glándulas sudoríparas y pulmón así como el papel del ENaC en la patogénesis de la enfermedad.

  9. Spatial and seasonal variations of the contamination within water body of the Grand Canal, China

    NARCIS (Netherlands)

    Wang, X.L.; Han, Jingyi; Xu, L.G.; Zhang, Q.

    2010-01-01

    To delineate the character of contaminations in the Grand Canal, China, a three-year study (2004-2006) was conducted to investigate variations the water quality in the canal. Results showed that the variation of water quality within the Grand Canal was of there is remarkable spatial and seasonal

  10. Endodontic treatment of two-canalled maxillary central and lateral incisors: a case report

    OpenAIRE

    Shokouhinejad, Noushin; Sheykhrezaee, Mohammad Saeed; Assadian, Hadi

    2009-01-01

    Familiarity with the intricacies and variations of root canal morphology is essential for successful endodontic treatment. Maxillary central and lateral incisors are known to be single-rooted with one canal, however, this case report describes endodontic treatment of maxillary central and lateral incisors with two buccopalatal root canals.

  11. Endodontic treatment of two-canalled maxillary central and lateral incisors: a case report

    Science.gov (United States)

    Shokouhinejad, Noushin; Sheykhrezaee, Mohammad Saeed; Assadian, Hadi

    2009-01-01

    Familiarity with the intricacies and variations of root canal morphology is essential for successful endodontic treatment. Maxillary central and lateral incisors are known to be single-rooted with one canal, however, this case report describes endodontic treatment of maxillary central and lateral incisors with two buccopalatal root canals. PMID:23940491

  12. A central incisor with 4 independent root canals: a case report

    NARCIS (Netherlands)

    Aznar Portoles, C.; Moinzadeh, A.T.; Shemesh, H.

    2015-01-01

    The maxillary central incisor is the tooth with the least anatomic variations. Despite the fact that several studies have reported a prevalence of 100% for the presence of a single canal, root canal aberrations of maxillary central incisors with up to 3 canals have also been reported. Such cases

  13. File list: Unc.Oth.05.AllAg.Schlemms_canal_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Unc.Oth.05.AllAg.Schlemms_canal_cells hg19 Unclassified Others Schlemms canal cells... http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/assembled/Unc.Oth.05.AllAg.Schlemms_canal_cells.bed ...

  14. File list: His.Oth.50.AllAg.Schlemms_canal_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available His.Oth.50.AllAg.Schlemms_canal_cells hg19 Histone Others Schlemms canal cells http...://dbarchive.biosciencedbc.jp/kyushu-u/hg19/assembled/His.Oth.50.AllAg.Schlemms_canal_cells.bed ...

  15. File list: DNS.Oth.50.AllAg.Schlemms_canal_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available DNS.Oth.50.AllAg.Schlemms_canal_cells hg19 DNase-seq Others Schlemms canal cells ht...tp://dbarchive.biosciencedbc.jp/kyushu-u/hg19/assembled/DNS.Oth.50.AllAg.Schlemms_canal_cells.bed ...

  16. File list: Unc.Oth.10.AllAg.Schlemms_canal_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Unc.Oth.10.AllAg.Schlemms_canal_cells hg19 Unclassified Others Schlemms canal cells... http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/assembled/Unc.Oth.10.AllAg.Schlemms_canal_cells.bed ...

  17. File list: Pol.Oth.05.AllAg.Schlemms_canal_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Pol.Oth.05.AllAg.Schlemms_canal_cells hg19 RNA polymerase Others Schlemms canal cel...ls http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/assembled/Pol.Oth.05.AllAg.Schlemms_canal_cells.bed ...

  18. Measurement and visualization of file-to-wall contact during ultrasonically activated irrigation in simulated canals

    NARCIS (Netherlands)

    Boutsioukis, C.; Verhaagen, B.; Walmsley, A.D.; Versluis, Michel; van der Sluis, L.W.M.

    2013-01-01

    Aim (i) To quantify in a simulated root canal model the file-to-wall contact during ultrasonic activation of an irrigant and to evaluate the effect of root canal size, file insertion depth, ultrasonic power, root canal level and previous training, (ii) To investigate the effect of file-to-wall

  19. File list: NoD.CDV.20.AllAg.Atrioventicular_canals [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available NoD.CDV.20.AllAg.Atrioventicular_canals mm9 No description Cardiovascular Atriovent...icular canals http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/NoD.CDV.20.AllAg.Atrioventicular_canals.bed ...

  20. File list: ALL.CDV.10.AllAg.Atrioventicular_canals [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available ALL.CDV.10.AllAg.Atrioventicular_canals mm9 All antigens Cardiovascular Atrioventic...ular canals SRX1271841 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/ALL.CDV.10.AllAg.Atrioventicular_canals.bed ...

  1. File list: ALL.CDV.05.AllAg.Atrioventicular_canals [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available ALL.CDV.05.AllAg.Atrioventicular_canals mm9 All antigens Cardiovascular Atrioventic...ular canals SRX1271841 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/ALL.CDV.05.AllAg.Atrioventicular_canals.bed ...

  2. File list: DNS.CDV.50.AllAg.Atrioventicular_canals [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available DNS.CDV.50.AllAg.Atrioventicular_canals mm9 DNase-seq Cardiovascular Atrioventicula...r canals http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/DNS.CDV.50.AllAg.Atrioventicular_canals.bed ...

  3. File list: InP.CDV.05.AllAg.Atrioventicular_canals [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available InP.CDV.05.AllAg.Atrioventicular_canals mm9 Input control Cardiovascular Atrioventi...cular canals http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/InP.CDV.05.AllAg.Atrioventicular_canals.bed ...

  4. File list: Oth.CDV.05.AllAg.Atrioventicular_canals [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Oth.CDV.05.AllAg.Atrioventicular_canals mm9 TFs and others Cardiovascular Atriovent...icular canals SRX1271841 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/Oth.CDV.05.AllAg.Atrioventicular_canals.bed ...

  5. File list: NoD.CDV.50.AllAg.Atrioventicular_canals [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available NoD.CDV.50.AllAg.Atrioventicular_canals mm9 No description Cardiovascular Atriovent...icular canals http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/NoD.CDV.50.AllAg.Atrioventicular_canals.bed ...

  6. File list: NoD.CDV.10.AllAg.Atrioventicular_canals [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available NoD.CDV.10.AllAg.Atrioventicular_canals mm9 No description Cardiovascular Atriovent...icular canals http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/NoD.CDV.10.AllAg.Atrioventicular_canals.bed ...

  7. File list: Pol.CDV.05.AllAg.Atrioventicular_canals [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Pol.CDV.05.AllAg.Atrioventicular_canals mm9 RNA polymerase Cardiovascular Atriovent...icular canals http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/Pol.CDV.05.AllAg.Atrioventicular_canals.bed ...

  8. File list: DNS.CDV.20.AllAg.Atrioventicular_canals [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available DNS.CDV.20.AllAg.Atrioventicular_canals mm9 DNase-seq Cardiovascular Atrioventicula...r canals http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/DNS.CDV.20.AllAg.Atrioventicular_canals.bed ...

  9. File list: DNS.CDV.10.AllAg.Atrioventicular_canals [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available DNS.CDV.10.AllAg.Atrioventicular_canals mm9 DNase-seq Cardiovascular Atrioventicula...r canals http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/DNS.CDV.10.AllAg.Atrioventicular_canals.bed ...

  10. File list: DNS.CDV.05.AllAg.Atrioventicular_canals [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available DNS.CDV.05.AllAg.Atrioventicular_canals mm9 DNase-seq Cardiovascular Atrioventicula...r canals http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/DNS.CDV.05.AllAg.Atrioventicular_canals.bed ...

  11. File list: InP.CDV.50.AllAg.Atrioventicular_canals [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available InP.CDV.50.AllAg.Atrioventicular_canals mm9 Input control Cardiovascular Atrioventi...cular canals http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/InP.CDV.50.AllAg.Atrioventicular_canals.bed ...

  12. IMPACT OF CANAL DESIGN LIMITATIONS ON WATER DELIVERY OPERATIONS AND AUTOMATION

    Science.gov (United States)

    Irrigation canals are often designed for water transmission. The design engineer simply ensures that the canal will pass the maximum design discharge. However, irrigation canals frequently operated far below design capacity. Because demands and the distribution of flow at bifurcations (branch points...

  13. 46 CFR 69.7 - Vessels transiting the Panama and Suez Canals.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Vessels transiting the Panama and Suez Canals. 69.7... MEASUREMENT OF VESSELS MEASUREMENT OF VESSELS General § 69.7 Vessels transiting the Panama and Suez Canals. (a) All vessels intending to transit the Panama Canal, other than vessels of war, must be measured and...

  14. 19 CFR 4.4 - Panama Canal; report of arrival required.

    Science.gov (United States)

    2010-04-01

    ... 19 Customs Duties 1 2010-04-01 2010-04-01 false Panama Canal; report of arrival required. 4.4... OF THE TREASURY VESSELS IN FOREIGN AND DOMESTIC TRADES Arrival and Entry of Vessels § 4.4 Panama Canal; report of arrival required. Vessels which merely transit the Panama Canal without transacting any...

  15. THE USE OF CUSTOMIZED GUTTA PERCHA FILLING MATERIAL IN WIDE ROOT CANAL SPACE

    Directory of Open Access Journals (Sweden)

    Dewa Ayu N. P. A. Dewa Ayu

    2006-04-01

    Full Text Available The necrotic tooth with incomplete formed roots and wide root canal should be treated by apexification. Gutta-percha combined with root canal sealer is widely used as an obturation material. The aim of this case report is to figure out that the use of customized gutta-percha in wide root canal to produce compact and hermetic filling.

  16. 33 CFR 401.49 - Dropping anchor or tying to canal bank.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Dropping anchor or tying to canal bank. 401.49 Section 401.49 Navigation and Navigable Waters SAINT LAWRENCE SEAWAY DEVELOPMENT... Dropping anchor or tying to canal bank. Except in an emergency, no vessel shall drop anchor in any canal or...

  17. The Ohio & Erie Canal: Catalyst of Economic Development for Ohio. Teaching with Historic Places.

    Science.gov (United States)

    Ayers, Deborah

    In the 19th century, canal boats pulled along by mules carried much cargo. The canal boat was the family business, their livelihood, and their home. In Ohio, these boats glided gracefully along the Ohio and Erie Canal, heavily laden with lumber on its way north to Lake Erie where it was transferred to a lake freighter and sent to Buffalo (New…

  18. Page 1 Steady flow Simulation in irrigation canals 967 Note :- 1 - 5 ...

    Indian Academy of Sciences (India)

    Steady flow Simulation in irrigation canals 967. Note :- 1 - 5 correspond to cases listed in table & Case". #. 400 800 1200 1600 20 *. 0 - 00 m Figure 5. Effect of canal con-. Distance dition on flow depth. 6.3 Backwater effect. By and large, canals are designed based on uniform flow criterion and control structures are also ...

  19. File list: Oth.CDV.10.AllAg.Atrioventicular_canals [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Oth.CDV.10.AllAg.Atrioventicular_canals mm9 TFs and others Cardiovascular Atrioventicular cana...ls SRX1271841 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/Oth.CDV.10.AllAg.Atrioventicular_canals.bed ...

  20. File list: ALL.CDV.20.AllAg.Atrioventicular_canals [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available ALL.CDV.20.AllAg.Atrioventicular_canals mm9 All antigens Cardiovascular Atrioventicular cana...ls SRX1271841 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/ALL.CDV.20.AllAg.Atrioventicular_canals.bed ...

  1. File list: InP.CDV.10.AllAg.Atrioventicular_canals [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available InP.CDV.10.AllAg.Atrioventicular_canals mm9 Input control Cardiovascular Atrioventicular cana...ls http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/InP.CDV.10.AllAg.Atrioventicular_canals.bed ...

  2. File list: Unc.Oth.20.AllAg.Schlemms_canal_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Unc.Oth.20.AllAg.Schlemms_canal_cells hg19 Unclassified Others Schlemms canal cells... http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/assembled/Unc.Oth.20.AllAg.Schlemms_canal_cells.bed ...

  3. File list: DNS.Oth.10.AllAg.Schlemms_canal_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available DNS.Oth.10.AllAg.Schlemms_canal_cells hg19 DNase-seq Others Schlemms canal cells ht...tp://dbarchive.biosciencedbc.jp/kyushu-u/hg19/assembled/DNS.Oth.10.AllAg.Schlemms_canal_cells.bed ...

  4. File list: DNS.Oth.05.AllAg.Schlemms_canal_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available DNS.Oth.05.AllAg.Schlemms_canal_cells hg19 DNase-seq Others Schlemms canal cells ht...tp://dbarchive.biosciencedbc.jp/kyushu-u/hg19/assembled/DNS.Oth.05.AllAg.Schlemms_canal_cells.bed ...

  5. File list: His.Oth.10.AllAg.Schlemms_canal_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available His.Oth.10.AllAg.Schlemms_canal_cells hg19 Histone Others Schlemms canal cells http...://dbarchive.biosciencedbc.jp/kyushu-u/hg19/assembled/His.Oth.10.AllAg.Schlemms_canal_cells.bed ...

  6. File list: His.Oth.20.AllAg.Schlemms_canal_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available His.Oth.20.AllAg.Schlemms_canal_cells hg19 Histone Others Schlemms canal cells http...://dbarchive.biosciencedbc.jp/kyushu-u/hg19/assembled/His.Oth.20.AllAg.Schlemms_canal_cells.bed ...

  7. File list: Oth.Oth.05.AllAg.Schlemms_canal_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Oth.Oth.05.AllAg.Schlemms_canal_cells hg19 TFs and others Others Schlemms canal cel...ls http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/assembled/Oth.Oth.05.AllAg.Schlemms_canal_cells.bed ...

  8. File list: ALL.Oth.05.AllAg.Schlemms_canal_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available ALL.Oth.05.AllAg.Schlemms_canal_cells hg19 All antigens Others Schlemms canal cells... http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/assembled/ALL.Oth.05.AllAg.Schlemms_canal_cells.bed ...

  9. File list: ALL.Oth.10.AllAg.Schlemms_canal_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available ALL.Oth.10.AllAg.Schlemms_canal_cells hg19 All antigens Others Schlemms canal cells... http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/assembled/ALL.Oth.10.AllAg.Schlemms_canal_cells.bed ...

  10. File list: InP.CDV.20.AllAg.Atrioventicular_canals [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available InP.CDV.20.AllAg.Atrioventicular_canals mm9 Input control Cardiovascular Atrioventicular cana...ls http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/InP.CDV.20.AllAg.Atrioventicular_canals.bed ...

  11. File list: DNS.Oth.20.AllAg.Schlemms_canal_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available DNS.Oth.20.AllAg.Schlemms_canal_cells hg19 DNase-seq Others Schlemms canal cells ht...tp://dbarchive.biosciencedbc.jp/kyushu-u/hg19/assembled/DNS.Oth.20.AllAg.Schlemms_canal_cells.bed ...

  12. File list: ALL.CDV.50.AllAg.Atrioventicular_canals [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available ALL.CDV.50.AllAg.Atrioventicular_canals mm9 All antigens Cardiovascular Atrioventicular cana...ls SRX1271841 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/ALL.CDV.50.AllAg.Atrioventicular_canals.bed ...

  13. File list: Oth.Oth.10.AllAg.Schlemms_canal_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Oth.Oth.10.AllAg.Schlemms_canal_cells hg19 TFs and others Others Schlemms canal cel...ls http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/assembled/Oth.Oth.10.AllAg.Schlemms_canal_cells.bed ...

  14. File list: Oth.Oth.50.AllAg.Schlemms_canal_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Oth.Oth.50.AllAg.Schlemms_canal_cells hg19 TFs and others Others Schlemms canal cel...ls http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/assembled/Oth.Oth.50.AllAg.Schlemms_canal_cells.bed ...

  15. File list: Pol.CDV.20.AllAg.Atrioventicular_canals [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Pol.CDV.20.AllAg.Atrioventicular_canals mm9 RNA polymerase Cardiovascular Atrioventicular cana...ls http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/Pol.CDV.20.AllAg.Atrioventicular_canals.bed ...

  16. File list: Pol.Oth.10.AllAg.Schlemms_canal_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Pol.Oth.10.AllAg.Schlemms_canal_cells hg19 RNA polymerase Others Schlemms canal cel...ls http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/assembled/Pol.Oth.10.AllAg.Schlemms_canal_cells.bed ...

  17. File list: ALL.Oth.20.AllAg.Schlemms_canal_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available ALL.Oth.20.AllAg.Schlemms_canal_cells hg19 All antigens Others Schlemms canal cells... http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/assembled/ALL.Oth.20.AllAg.Schlemms_canal_cells.bed ...

  18. File list: Unc.Oth.50.AllAg.Schlemms_canal_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Unc.Oth.50.AllAg.Schlemms_canal_cells hg19 Unclassified Others Schlemms canal cells... http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/assembled/Unc.Oth.50.AllAg.Schlemms_canal_cells.bed ...

  19. File list: Pol.CDV.50.AllAg.Atrioventicular_canals [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Pol.CDV.50.AllAg.Atrioventicular_canals mm9 RNA polymerase Cardiovascular Atrioventicular cana...ls http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/Pol.CDV.50.AllAg.Atrioventicular_canals.bed ...

  20. File list: Oth.CDV.50.AllAg.Atrioventicular_canals [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Oth.CDV.50.AllAg.Atrioventicular_canals mm9 TFs and others Cardiovascular Atrioventicular cana...ls SRX1271841 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/Oth.CDV.50.AllAg.Atrioventicular_canals.bed ...

  1. File list: Pol.CDV.10.AllAg.Atrioventicular_canals [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Pol.CDV.10.AllAg.Atrioventicular_canals mm9 RNA polymerase Cardiovascular Atrioventicular cana...ls http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/Pol.CDV.10.AllAg.Atrioventicular_canals.bed ...

  2. File list: Oth.CDV.20.AllAg.Atrioventicular_canals [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Oth.CDV.20.AllAg.Atrioventicular_canals mm9 TFs and others Cardiovascular Atrioventicular cana...ls SRX1271841 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/Oth.CDV.20.AllAg.Atrioventicular_canals.bed ...

  3. File list: Pol.Oth.50.AllAg.Schlemms_canal_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Pol.Oth.50.AllAg.Schlemms_canal_cells hg19 RNA polymerase Others Schlemms canal cel...ls http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/assembled/Pol.Oth.50.AllAg.Schlemms_canal_cells.bed ...

  4. File list: His.Oth.05.AllAg.Schlemms_canal_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available His.Oth.05.AllAg.Schlemms_canal_cells hg19 Histone Others Schlemms canal cells http...://dbarchive.biosciencedbc.jp/kyushu-u/hg19/assembled/His.Oth.05.AllAg.Schlemms_canal_cells.bed ...

  5. File list: Oth.Oth.20.AllAg.Schlemms_canal_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Oth.Oth.20.AllAg.Schlemms_canal_cells hg19 TFs and others Others Schlemms canal cel...ls http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/assembled/Oth.Oth.20.AllAg.Schlemms_canal_cells.bed ...

  6. File list: NoD.CDV.05.AllAg.Atrioventicular_canals [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available NoD.CDV.05.AllAg.Atrioventicular_canals mm9 No description Cardiovascular Atrioventicular cana...ls http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/NoD.CDV.05.AllAg.Atrioventicular_canals.bed ...

  7. File list: Pol.Oth.20.AllAg.Schlemms_canal_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Pol.Oth.20.AllAg.Schlemms_canal_cells hg19 RNA polymerase Others Schlemms canal cel...ls http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/assembled/Pol.Oth.20.AllAg.Schlemms_canal_cells.bed ...

  8. Endodontic Treatment of a Mandibular Second Premolar with Three Roots and Three Canals

    Directory of Open Access Journals (Sweden)

    Bonny Paul

    2014-01-01

    Full Text Available Complex root canal system with atypical variations is a common finding among mandibular premolars. Endodontic treatment in these teeth may not be successful due to the failure to recognise and treat multiple canals. This paper presents endodontic treatment of a mandibular second premolar with three roots and three canals.

  9. Entrenamiento de una red neuronal multicapa para la tasa de cambio euro - dólar (EUR/USD

    Directory of Open Access Journals (Sweden)

    Jaime Alberto Villamil Torres

    2007-09-01

    Full Text Available Tanto para los inversionistas como para las autoridades económicas es necesario que se desarrolle una herramienta matemática que logre dar cuenta de la dirección de una variable como el tipo de cambio (el precio relativo entre dos monedas. Muchos de los mecanismos usados actualmente están basados en el uso de técnicas estadísticas, en particular series de tiempo lineales. Las redes neuronales artificiales (RNA son modelos matemáticos que pretenden emular el funcionamiento del cerebro humano, su aplicación en economía e ingeniería surge a finales de los años ochenta con buenos resultados. Las RNA se presentan como una alternativa para simular el comportamiento de variables financieras que, por lo general, tienden a parecerse a un paseo aleatorio. En este trabajo se muestran los resultados del entrenamiento de una red neuronal para negociación de la tasa de cambio EUR/USD y las bondades del algoritmo de entrenamiento chemotaxis, que permite entrenar redes que maximicen una función objetivo que relacione aciertos en la predicción con las ganancias de un trader.

  10. [The use of ultrasonic files in canal preparation].

    Science.gov (United States)

    Calas, P; Terrie, B

    1990-01-01

    The continuous high volume of irrigating solution delivered by the ultrasonic system facilitates the root canal debridement. An excellent cleaning of dentin wall is obtained even on surfaces unreached by the mechanical instrumentation. In order to obtain an efficacious preparation, the use of ultrasonic files were combined with instrumentation. This new technique is described in this article.

  11. Evaluation of complications of root canal treatment performed by ...

    African Journals Online (AJOL)

    Mothanna K. AlRahabi

    2017-07-05

    Jul 5, 2017 ... This study evaluated the technical quality of root canal treatment (RCT) and detected iatrogenic errors in an undergraduate dental clinic at the College of Dentistry, Taibah. University, Saudi Arabia. Dental records of 280 patients who received RCT between 2013 and 2016 undertaken by dental students ...

  12. Radiologic classification of superior canal dehiscence : Implications for surgical repair

    NARCIS (Netherlands)

    Lookabaugh, Sarah; Kelly, Hillary R.; Carter, Margaret S.; Niesten, Marlien E F|info:eu-repo/dai/nl/377125202; McKenna, Michael J.; Curtin, Hugh; Lee, Daniel J.

    2015-01-01

    Objective: Surgical access to repair a superior canal dehiscence (SCD) is influenced by the location of the bony defect and its relationship to surrounding tegmen topography as seen on computed tomography. There are currently no agreed-upon methods of characterizing these radiologic findings. We

  13. Acoustic impedances of ear canals measured by impedance tube

    DEFF Research Database (Denmark)

    Ciric, Dejan; Hammershøi, Dorte

    2007-01-01

    During hearing sensitivity tests, the sound field is commonly generated by an earphone placed on a subject ear. One of the factors that can affect the sound transmission in the ear is the acoustic impedance of the ear canal. Its importance is related to the contribution of other elements involved...

  14. Pneumocystis jirovecii infection of the external auditory canal ...

    African Journals Online (AJOL)

    Pneumocystis jirovecii is well known to cause interstitial plasma cell pneumonia in immunocompromised patients. It has been implicated as a rare cause of infections in other anatomical sites.¹ We report a rare case of P. jirovecii infection of the external auditory canal. This was the first manifestation of a previously unknown ...

  15. Assessment of lumbar spinal canal stenosis by magnetic resonance phlebography

    Energy Technology Data Exchange (ETDEWEB)

    Manaka, Masakazu; Komagata, Masashi; Endo, Kenji; Imakiire, Atsuhiro [Tokyo Medical Coll. (Japan)

    2003-07-01

    There is evidence to suggest that cauda equina intermittent claudication is caused by local circulatory disturbances in the cauda equina as well as compression of the cauda equina. We evaluated the role of magnetic resonance phlebography (MRP) in identifying circulatory disturbances of the vertebral venous system in patients with lumbar spinal canal stenosis. Extensive filling defects of the anterior internal vertebral venous plexus were evident in patients with lumbar spinal canal stenosis (n=53), whereas only milder abnormalities were noted in patients with other lumber diseases (n=16) and none in normal subjects (n=13). The extent of the defect on MRP correlated with the time at which intermittent claudication appeared. In patients with lumber spinal canal stenosis, extensive defects of the internal vertebral venous plexus on MRP were noted in the neutral spine position, but the defect diminished with anterior flexion of the spine. This phenomenon correlated closely with the time at which intermittent claudication appeared. Our results highlight the importance of MRP for assessing the underlying mechanism of cauda equina intermittent claudication in patients with lumbar spinal canal stenosis and suggest that congestive venous ischemia is involved in the development of intermittent claudication in these patients. (author)

  16. Microtensile bond strength between adhesive cements and root canal dentin

    OpenAIRE

    Bouillaguet, Serge; Troesch, Sabra; Wataha, John C.; Krejci, Ivo; Meyer, Jean Marc; Pashley, David H

    2003-01-01

    The hypotheses tested were that the bond strength of adhesive cements to root canal dentin (1) would be reduced as a function of configuration factor, polymerization process and type of luting material and (2) would be lowered near the apex of the tooth.

  17. Scanning electron microscopic evaluation of root canal surfaces ...

    African Journals Online (AJOL)

    2014-07-15

    Jul 15, 2014 ... Root canal preparation for all the teeth was carried out with. 3 different types of rotary instruments. ... which enabled removal of overlapping dentin walls. After completing the preparation of the coronal third of ... on dentine or other surfaces after instrumentation with either rotary instrument or endodontic files, ...

  18. Evaluation of complications of root canal treatment performed by ...

    African Journals Online (AJOL)

    Dental records of 280 patients who received RCT between 2013 and 2016 undertaken by dental students were investigated by retrospective chart review. Root canal obturation was evaluated on the basis of the length of obturation being ≤2 mm from the radiographic apex, with uniform radiodensity and good adaptation

  19. Scanning electron microscopic evaluation of root canal surfaces ...

    African Journals Online (AJOL)

    Scanning electron microscopic evaluation of root canal surfaces prepared with three rotary endodontic systems: Lightspeed, ProTaper and EndoWave. ... presence or absence of debris and smear layer and the photographs were taken at coronal, middle and apical 1/3 with a magnification of ~200 and ~1000 respectively.

  20. Working Length Determination of Root Canal of Young Permanent ...

    African Journals Online (AJOL)

    Background: Determination of correct working length is one of the keys to success in endodontic therapy. Aim: The aim of this study was to evaluate the diagnostic efficacy of various methods to determine working length of root canal. Materials and Methods: Tactile method was assessed using digital radiography and ...

  1. Assessment of Irrigation Performance along the Canal Reach of ...

    African Journals Online (AJOL)

    This paper presents the results of irrigation performance assessment made along the canal reaches of community-managed Hare irrigation scheme in. Southern Ethiopia. Field measurement, interview, group discussion and measurement of water supply were undertaken, and output performance indicators were assessed.

  2. Microhardness of different resin cement shades inside the root canal.

    Science.gov (United States)

    Vignolo, Valeria; Fuentes, Maria-Victoria; Garrido, Miguel-Angel; Rodríguez, Jesús; Ceballos, Laura

    2012-09-01

    To compare microhardness along the root canal post space of two resin cements in different shades and a dual-cure resin core material. Root canals of 21 bovine incisors were prepared for post space. Translucent posts (X∘Post, Dentsply DeTrey) were luted using one the following resin luting agent: Calibra (Dentsply DeTrey) in Translucent, Medium and Opaque shades, RelyX Unicem (3M ESPE) in Translucent, A2 and A3 shades and the dual-cure resin core material Core∘X flow. All materials were applied according to manufacturers' instructions and were all photopolymerized (Bluephase LED unit, Ivoclar Vivadent, 40s). After 24 hours, roots were transversally cut into 9 slices 1 mm thick from the coronal to apical extremes, three corresponding to each root third. Then, VHNs were recorded (100gf, 30 s) on the resin luting materials along the adhesive interface in all sections. Data were analyzed by two-way ANOVA and SNK tests (α=0.05). A significant influence on microhardness of resin luting material in their respective shades (pmicrohardness values and Calibra the lowest, regardless of the shade selected. All resin luting materials tested exhibited a significantly higher microhardness in the cervical third. Microhardness of resin luting agents tested inside the canal is dependent on material brand and resin cement shade seems to be a less relevant factor. Microhardness decreased along the root canal, regardless of the shade selected.

  3. Vessel electrification feasibility study for the New York state canals.

    Science.gov (United States)

    2013-10-01

    The objective of this study was to determine the technical and economic feasibility of repowering a diesel-fueled : New York State Canal Corporation (NYSCC) work boat with a diesel hybrid-electric or full-electric powertrain. : The project team instr...

  4. Radiographic Localization of the Mental Foramen and Mandibular Canal

    Directory of Open Access Journals (Sweden)

    Farzaneh Afkhami

    2013-01-01

    Full Text Available Objective: Accurately localizing the mental foramen and mandibular canal is important when administering local anesthesia and performing surgery; therefore, knowing the normal range of the possible locations is essential. Our purpose was to assess the location of the mental foramen and mandibular canal in an Iranian population using panoramic radiography.Materials and Methods: Standard panoramic radiographies were performed. The positions of 100 mental foramens were evaluated. The distances from the center of the mental foramen to the superior and inferior borders of the mandible and to the apexes of the first and second premolar were measured. The distance of the mental foramens from the mandibular midline and the diameter of the mandibular canal in the mental foramen connection were also measured.Results: Among 100 mental foramens, 6% were positioned under the first premolar, 24% were between the first and second premolars, 67% were under the second premolar, and the remaining 3% were behind the second premolar. The mean distance from the mental foramen to the mandibular midline was 27.77±3.20 mm. The mean diameter of the mandibular canal in the mental foramen connection was 3.09±0.69mm.Conclusion: The mental foramen was near the second premolar and the inferior border of the mandible. This information can be used to perform safer mental nerve blocks in surgical interventions.

  5. Canal + Spain & Live Football Broadcasts: A Whole Different Game

    NARCIS (Netherlands)

    Rodríguez Ortega, Vicente; Romero Santos, Rubén

    2017-01-01

    textabstractIn 1988 the Law for Private Television Broadcasting was approved by Spanish parliament. Three licenses were initially awarded. Soon thereafter, in 1990, three channels started broadcasting: Antena 3, Berlusconi-related Tele 5 and, against all odds, a pay channel, Canal + Spain. This

  6. Radiographic Localization of the Mental Foramen and Mandibular Canal

    Science.gov (United States)

    Afkhami, Farzaneh; Haraji, Afshin; Boostani, Hamid Reza

    2013-01-01

    Objective: Accurately localizing the mental foramen and mandibular canal is important when administering local anesthesia and performing surgery; therefore, knowing the normal range of the possible locations is essential. Our purpose was to assess the location of the mental foramen and mandibular canal in an Iranian population using panoramic radiography. Materials and Methods: Standard panoramic radiographies were performed. The positions of 100 mental foramens were evaluated. The distances from the center of the mental foramen to the superior and inferior borders of the mandible and to the apexes of the first and second premolar were measured. The distance of the mental foramens from the mandibular midline and the diameter of the mandibular canal in the mental foramen connection were also measured. Results: Among 100 mental foramens, 6% were positioned under the first premolar, 24% were between the first and second premolars, 67% were under the second premolar, and the remaining 3% were behind the second premolar. The mean distance from the mental foramen to the mandibular midline was 27.77±3.20 mm. The mean diameter of the mandibular canal in the mental foramen connection was 3.09±0.69mm. Conclusion: The mental foramen was near the second premolar and the inferior border of the mandible. This information can be used to perform safer mental nerve blocks in surgical interventions. PMID:24910651

  7. Anatomo-radiological study of the Superior Semicircular Canal Dehiscence

    Energy Technology Data Exchange (ETDEWEB)

    Crovetto, M., E-mail: macdlt@telefonica.net [Otolaryngology Department, Hospital de Basurto, University of the Basque Country, Avenida de Montevideo 18, Bilbao 48013, Vizcaya (Spain); Whyte, J., E-mail: jwhite@unizar.es [Faculty of Medicine, Department of Human Anatomy and Histology, University of Zaragoza, C/Domingo Mirall s/n, Zaragoza (Spain); Rodriguez, O.M., E-mail: OLIVIAMARIA.RODRIGUEZSANVICENT@osakidetza.net [Hospital de Cruces, Baracaldo, Vizcaya (Spain); Lecumberri, I., E-mail: INIGO.LECUMBERRICORTES@osakidetza.net [Hospital de Basurto, Avenida Montevideo 18, Bilbao 498013 (Spain); Martinez, C., E-mail: claudiorayosx@yahoo.es [Hospital General de la Defensa, Via Iberica s/n Zaragoza (Spain); Elexpuru, J., E-mail: jelexpuru@mac.com [Hospital de Basurto, Avenida de Montevideo 18, Bilbao 48013, Vizcaya (Spain)

    2010-11-15

    Introduction: The main purpose of this study is to determine the radiological incidence of Superior (SSCD) and Posterior Semicircular Canal Dehiscence (PSCD) and to compare radiologic SSCD to the incidence of this condition on cadaver specimen. We have also analysed the relation between the ossification state of the semicircular canals and the degree of mastoid pneumatization and integrity of Tegmen Tympani. Material and methods: Temporal bones have been investigated by means of CT scan on patients and direct observation on cadaver specimen, respectively. Results: 604 ears and 160 cadaver temporal bones have been investigated by means of CT scan and direct observation, respectively. 3.6% and 0.3% of the studied ears had SSCD and PSCD, respectively, on CT scan. Only 0.6% of the cadaver specimen ears did have anatomical SSCD. Degree of pneumatization of the mastoid bone is related to the mean thickness of bone overlying the Superior and Posterior Semicircular Canal. Radiological absence of Tegmen Tympani is more frequent in ears that also have radiologic SSCD. Conclusion: CT scanning gives higher incidence figures of SSCD than anatomical studies, 3.6% vs. 0.6%. We also found a 0.6% incidence of radiological PSCD in the studied ears. There is a direct relation between the degree of ossification of Superior and Posterior Semicircular Canal and certain temporal bone anatomic features: temporal bone pneumatization and absence/presence of Tegmen Tympani or Antri.

  8. Source location encoding in the fish lateral line canal

    NARCIS (Netherlands)

    Curcic-Blake, B; van Netten, SM

    2006-01-01

    The position of a hydrodynamic dipole source, as encoded in a linear array of mechano-detecting neuromasts in the fish lateral line canal, was electrophysiologically investigated. Measured excitation patterns along the lateral line were compared to theoretical predictions and were found to be in

  9. Atlantoaxial dislocation associated with stenosis of canal at atlas.

    Directory of Open Access Journals (Sweden)

    Goel A

    1997-07-01

    Full Text Available Three rare cases of stenosis of spinal canal at the level of atlas associated with atlantoaxial dislocation are presented. An atlantoaxial lateral mass fixation with plate and screws after posterior midline bony decompression was successfully performed in these cases.

  10. Closure of the vertebral canal in human embryos and fetuses

    NARCIS (Netherlands)

    Mekonen, Hayelom K.; Hikspoors, Jill P. J. M.; Mommen, Greet; Kruepunga, Nutmethee; Köhler, S. Eleonore; Lamers, Wouter H.

    2017-01-01

    The vertebral column is the paradigm of the metameric architecture of the vertebrate body. Because the number of somites is a convenient parameter to stage early human embryos, we explored whether the closure of the vertebral canal could be used similarly for staging embryos between 7 and 10weeks of

  11. Lightlike Hypersurfaces and Canal Hypersurfaces of Lorentzian Surfaces

    Directory of Open Access Journals (Sweden)

    Jianguo Sun

    2014-01-01

    Full Text Available The lightlike hypersurfaces in semi-Euclidean space are of special interest in Relativity Theory. In particular, the singularities of these lightlike hypersurfaces provide good models for the study of different horizon types. And we obtain some geometrical propositions of the canal hypersurfaces of Lorentzian surfaces. We introduce the notions of flatness for these hypersurfaces and study their singularities.

  12. Digestive enzymes in the alimentary canal of Clarias anguillaris ...

    African Journals Online (AJOL)

    Three groups of digestive enzymes were observed in the alimentary canals of the fingerlings and adults of Clarias anguillaris. The enzymes were carbohydrases including amylase, sucrase, lactase and maltase, proteases including peptase, tryptase and peptidase, and lipase. The activities of the protease were found to be ...

  13. Evaluation of various filling techniques in distal canals of mandibular ...

    African Journals Online (AJOL)

    Background and Aims: The aim of this study was to evaluate the quality of various filling techniques in distal canals of mandibular molars instrumented with different single-file nickel-titanium (NiTi) systems. Materials and Methods: A total of 150 distal roots of mandibular molar teeth were randomly assigned into three main ...

  14. Clinical evaluation of posterior canal benign paroxysmal positional ...

    African Journals Online (AJOL)

    However, successful treatment is dependent on accurate identification of the implicated canal and the form of lithiasis. Furthermore, clinicians should note that there is no place for pharmacological treatment of BPPV; unless it is to facilitate repositioning. Keywords: Benign paroxysmal positional vertigo, canalith repositioning ...

  15. External Auditory Canal Stenosis After Traumatic Auricular Amputation

    NARCIS (Netherlands)

    Wong Chung, J.E.; Chussi, D.C; Heerbeek, N. van

    2017-01-01

    BACKGROUND: The auricles are easily injured or amputated in case of head trauma. Inadequate treatment of the external auditory canal (EAC) after auricular injury is often seen and can lead to significant complications of the EAC. CASE REPORT: The authors report 4 cases of auricular injury or

  16. Evaluation of Various Filling Techniques in Distal Canals of ...

    African Journals Online (AJOL)

    2017-03-06

    Mar 6, 2017 ... among the groups, the analysis was continued with post hoc comparisons using Tamhane's, Dunnett's, or Mann-. Whitney U-test. Bonferroni's correction was applied (P. < 0.05/n; where n = a ..... canal preparation with NiTi rotary instruments: Rationale, performance and safety. Status report for the American.

  17. Interactions between root canal irrigants, sealers and dentin

    NARCIS (Netherlands)

    Neelakantan, P.

    2016-01-01

    The objective of this thesis was to determine the interactions between root filling materials and root dentin and to investigate if root canal irrigating solutions had an impact on these interactions. The following outcomes were assessed in the studies encompassed in this thesis: (i) dislocation

  18. Estudio micológico de El Canal y Los Tiles (La Palma, Islas Canarias. V. Datos adicionales

    Directory of Open Access Journals (Sweden)

    Leal, Julio

    2009-12-01

    Full Text Available An annotated catalogue of 66 taxa, collected in the early MAB Reserve El Canal y Los Tiles is presented. Among these taxa, 11 species are new for La Palma island and 5 are recorded for the first time in the Canary Islands. Taxonomic comments on some critical species and information about the distribution in the Macaronesian bioregion of all the studied taxa are given. Based on our previous publications, global data on biodiversity, substrates and distribution of the mycobiota in the different plant communities present in the sampled area are analyzed.

    Se presenta un estudio sobre 66 especies, pertenecientes a las divisiones Myxomycota (21, Ascomycota (29 y Basidiomycota (16, encontradas en la antigua Reserva de la Biosfera El Canal y Los Tiles. De ellas 11 se citan por primera vez para la isla de La Palma, siendo 5 de éstas nuevas para Canarias. Se hacen comentarios taxonómicos sobre algunos táxones conflictivos, además de amplia información sobre su distribución en la Región Macaronésica. En base a publicaciones propias anteriores, se aportan datos globales sobre biodiversidad, sustratos y distribución de la micobiota en las diferentes unidades ambientales presentes en el área de estudio.

  19. Nanodiamond–Gutta Percha Composite Biomaterials for Root Canal Therapy

    Science.gov (United States)

    2015-01-01

    Root canal therapy (RCT) represents a standard of treatment that addresses infected pulp tissue in teeth and protects against future infection. RCT involves removing dental pulp comprising blood vessels and nerve tissue, decontaminating residually infected tissue through biomechanical instrumentation, and root canal obturation using a filler material to replace the space that was previously composed of dental pulp. Gutta percha (GP) is typically used as the filler material, as it is malleable, inert, and biocompatible. While filling the root canal space with GP is the standard of care for endodontic therapies, it has exhibited limitations including leakage, root canal reinfection, and poor mechanical properties. To address these challenges, clinicians have explored the use of alternative root filling materials other than GP. Among the classes of materials that are being explored as novel endodontic therapy platforms, nanodiamonds (NDs) may offer unique advantages due to their favorable properties, particularly for dental applications. These include versatile faceted surface chemistry, biocompatibility, and their role in improving mechanical properties, among others. This study developed a ND-embedded GP (NDGP) that was functionalized with amoxicillin, a broad-spectrum antibiotic commonly used for endodontic infection. Comprehensive materials characterization confirmed improved mechanical properties of NDGP over unmodified GP. In addition, digital radiography and microcomputed tomography imaging demonstrated that obturation of root canals with NDGP could be achieved using clinically relevant techniques. Furthermore, bacterial growth inhibition assays confirmed drug functionality of NDGP functionalized with amoxicillin. This study demonstrates a promising path toward NDGP implementation in future endodontic therapy for improved treatment outcomes. PMID:26452304

  20. Position and course of the mandibular canal in skulls.

    Science.gov (United States)

    Ozturk, Ayla; Potluri, Anitha; Vieira, Alexandre R

    2012-04-01

    The aim of this study was to examine and describe the topography of the mandibular canal (MC) in both vertical and occlusal dimensions. Fifty-two adult skulls deposited in the University of Pittsburgh School of Dental Medicine skull collection were evaluated in this study. Cone-beam computerized tomographic scans of each skull were obtained. The vertical course of MC was classified into 3 types: straight projection (12.2%), catenary-like configuration (51.1%), and progressive descent from posterior to anterior (36.7%). The evaluation of the buccolingual dimension showed that the mandibular canal was located either in contact with or close to the lingual cortical plate (≤ 2 mm) in the molar region of the majority of the cases. As it proceeds anteriorly it moves toward the buccal aspect of the mandible, where it finally emerges through the mental foramen. Three emerging patterns of mandibular canal were observed: sharp turn (53.2%), soft curved exit (28.8%), and straight path (17.4%). The examination of the vertical dimension showed that the canal was located almost 1 cm above the inferior border of the mandible and then ascended to reach the mental foramen, which is located ~16 mm (range 13.4-20.3 mm) above the inferior border of the mandible. We found a strong correlation between height of the mandible and location of the mental foramen (r = 0.64; P mandibular canal described in vertical and axial dimensions and variation in its path have been classified. In addition to variation in location of MC, it has different anatomic configurations which clinicians should be familiar with in any surgical procedures involving the posterior mandible. Copyright © 2012 Elsevier Inc. All rights reserved.

  1. Determinants of spatial and temporal coding by semicircular canal afferents.

    Science.gov (United States)

    Highstein, Stephen M; Rabbitt, Richard D; Holstein, Gay R; Boyle, Richard D

    2005-05-01

    The vestibular semicircular canals are internal sensors that signal the magnitude, direction, and temporal properties of angular head motion. Fluid mechanics within the 3-canal labyrinth code the direction of movement and integrate angular acceleration stimuli over time. Directional coding is accomplished by decomposition of complex angular accelerations into 3 biomechanical components-one component exciting each of the 3 ampullary organs and associated afferent nerve bundles separately. For low-frequency angular motion stimuli, fluid displacement within each canal is proportional to angular acceleration. At higher frequencies, above the lower corner frequency, real-time integration is accomplished by viscous forces arising from the movement of fluid within the slender lumen of each canal. This results in angular velocity sensitive fluid displacements. Reflecting this, a subset of afferent fibers indeed report angular acceleration to the brain for low frequencies of head movement and report angular velocity for higher frequencies. However, a substantial number of afferent fibers also report angular acceleration, or a signal between acceleration and velocity, even at frequencies where the endolymph displacement is known to follow angular head velocity. These non-velocity-sensitive afferent signals cannot be attributed to canal biomechanics alone. The responses of non-velocity-sensitive cells include a mathematical differentiation (first-order or fractional) imparted by hair-cell and/or afferent complexes. This mathematical differentiation from velocity to acceleration cannot be attributed to hair cell ionic currents, but occurs as a result of the dynamics of synaptic transmission between hair cells and their primary afferent fibers. The evidence for this conclusion is reviewed below.

  2. Síndrome do canal de Guyon causada por cisto sinovial Guyon's canal syndrome due to a synovial cyst

    Directory of Open Access Journals (Sweden)

    Evandro Silva Ruas

    2010-01-01

    Full Text Available Apresentamos um caso de síndrome do canal de Guyon por um cisto sinovial no punho esquerdo de uma paciente do sexo feminino, de 48 anos. A paciente apresentava dor e parestesia na topografia do nervo ulnar, diminuição da força muscular e deformidade na mão esquerda. A eletroneuromiografia evidenciava compressão do nervo ulnar no nível do punho. Realizada a ressecção do cisto e descompressão do nervo no canal de Guyon. Após a cirurgia a paciente apresentou melhora da dor e da parestesia, além de aumento do trofismo muscular e correção da deformidade.The authors present a case of Guyon's canal syndrome due to a synovial cyst within the left wrist of a 48-year-old female patient. The patient reported pain and paresthesia in the topography of the ulnar nerve, loss of muscular strength and left hand deformity. Electromyography showed a compression of the ulnar nerve at the wrist level. Surgical decompression at the Guyon canal with resection of the cyst was performed. After surgery, the patient presented with improvement of pain and paresthesia, as well as an increase in muscular trophism and correction of the deformity.

  3. The width of the incisive canal and labial alveolar bone of the incisive canal: an assessment on CT images

    Energy Technology Data Exchange (ETDEWEB)

    Roh, Yang Gyun; Jang, Hyun Seon; Kim, Byung Ock; Kim, Jin Soo [Chosun Univ. College of Dentistry, Gwangju (Korea, Republic of)

    2006-09-15

    To assess the width of the labial alveolar bone of the incisive canal and the width of the incisive canal on spiral computed tomographic images of the anterior portion of the maxilla. Study materials included 38 CT scans taken for preoperative planning of implant placement. Axial cross-sectioned image entirely showing the incisive canal at an orifice to the oral cavity, middle portion, and an orifice to the nasal cavity and the diameter of the incisive canal at the middle portion were determined by two specialist using Digora for Windows 2.1. The statistical analyses were carried out using SPSS 12.0.1. When the maxillary central incisors remained, the mean labial alveolar bone width were 6.81{+-}1.41 mm, 6.46{+-}1.33 mm, and 7.91{+-}1.33 mm. When the maxillary central incisors were missed the mean width were 5.42{+-}2.20 mm, 6.23{+-}2.29 mm, and 7.89{+-}2.13 mm. The labial alveolar bone width at middle portion and an orifice to the nasal cavity were of no statistical significant difference according to presence of the maxillary central incisors (P>0.05). The width between oral cavity and nasal cavity, middle portion and to masal cavity revealed statistically significant difference (P<0.05)

  4. [Canal Finder System 89!!! Improvements and indications after 4 years of experimentation and use].

    Science.gov (United States)

    Lévy, G

    1990-01-01

    Actually, the CANAL FINDER SYSTEM is the only entirely automated endodontic device. After four years of existence, many evaluations were able to show the qualities of this system regarding root canal penetration, cleaning and shaping. The earlier concerns such as ergonomical problems were solved: automated extraction of the K-file, automated sodium hypochlorite irrigation. A new file was created, particularly well adapted to the root canal shaping of curved canals. This addition has improved the efficiency of the automated instrumentation. The CANAL FINDER SYSTEM has reached a maturity level permitting an excellent reliability and ease of use.

  5. Nonsurgical Endodontic Retreatment of Maxillary Second Molar with Two Palatal Root Canals: A Case Report

    Directory of Open Access Journals (Sweden)

    Mahsa Eskandarinezhad

    2012-04-01

    Full Text Available Successful endodontic treatment requires thorough knowledge regarding each root canal system of any tooth and probability of extra canals should be considered. Second maxillary molar with two palatal root canals is not frequent and its incidence reported in literatures is about 0.4–2%. The present case report describes non-surgical retreatment of maxillary second molar with two palatal root canals. Radiographic interpretation is difficult in this region; so, very careful examination of pulpal space and using supportive devices such as loupe and operating microscope is recommended to discover any unusual anatomic features like extra canals.

  6. Managing a mandibular second premolar with three-canal and taurodontism: a case report.

    Science.gov (United States)

    Mokhtari, Hadi; Niknami, Mahdi; Zand, Vahid

    2013-01-01

    Root canal anatomy diversity and aberrations are common especially in permanent dentition. A thorough understanding of the basic root canal anatomy and its diversities are necessary for successful endodontic treatment. Mandibular second premolars are usually single-rooted and have one root canal. Incidence of three separate root canals in this tooth is quite rare and taurodontism with three separate canals has never been reported in literature so far. The use of cone-beam computed tomography scan in this rare case greatly contributed to making a confirmatory diagnosis and successful nonsurgical endodontic management thereafter.

  7. MIMO LPV State-Space Identification of Open-Flow Irrigation Canal Systems

    Directory of Open Access Journals (Sweden)

    Yolanda Bolea

    2012-01-01

    Full Text Available Canal systems are complex nonlinear, distributed parameter systems with changing parameters according to the operating point. In this paper, a linear parameter-varying (LPV state-space canal control model is obtained by identification in a local way using a multimodel approach. This LPV identification procedure is based on subspace methods for different operating points of an irrigation canal covering the full operation range. Different subspace algorithms have been used and compared. The model that best represents the canal behavior in a precise manner has been chosen, and it has been validated by error functions and analysis correlation of residuals in a laboratory multireach pilot canal providing satisfactory results.

  8. A cone-beam computed tomography study of the root canal morphology of mandibular first premolars and the location of root canal orifices and apical foramina in a Chinese subpopulation.

    Science.gov (United States)

    Yang, Haibing; Tian, Cheng; Li, Guoju; Yang, Lin; Han, Xuan; Wang, Yan

    2013-04-01

    Successful root canal treatment is dependent on detailed knowledge of the morphology of the root canal system. The aim of this study was to investigate the morphology of the root canal systems of mandibular first premolars and the location of root canal orifices and apical foramina in a Chinese subpopulation using cone-beam computed tomography scanning. A total of 440 cone-beam computed tomographic images of mandibular first premolars were obtained from 238 patients. Tooth position, root canal morphology, the distance between the apical foramen and the anatomic apex, and the distance between the 2 root canal orifices of mandibular first premolars with 2 root canals were investigated. The Fisher exact test was used to analyze the correlation between the number of root canals and tooth position. Overall, 1.14% (n = 5) of the teeth had a C-shaped root canal system, 77.14% (n = 335) had 1 root canal, and 22.05% (n = 97) had 2 root canals from type II to type V. The remaining 0.68% (n = 3) were classified as type VIII, which had 3 root canals. The most frequent distribution of the distance between the apical foramen and the anatomic apex in 335 mandibular first premolars with 1 root canal was 1-2 mm (n = 192). The distance between the apical foramen and the anatomic apex of mandibular first premolars with 2 root canals was in accord with that of mandibular first premolars with 1 root canal. The distance between the 2 root canal orifices of mandibular first premolars with 2 root canals was approximately 13 mm. Most mandibular first premolars had 1 root canal. More than 1 of 5 mandibular first premolars had complex root canal systems (with 2 or more root canals). This study provides supplemental information about the root canals of mandibular first premolars in a Chinese subpopulation. Copyright © 2013 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  9. Los canales infantiles politemáticos de televisión digital en España: análisis y clasificación

    Directory of Open Access Journals (Sweden)

    Irene Melgarejo Moreno

    2011-11-01

    Full Text Available Los nuevos aportes tecnológicos y el desarrollo de la digitalización han hecho posible que hoy día exista una “amplia” gama de Canales Infantiles Politemáticos de televisión que se han convertido en una alternativa para los más pequeños. Con esta investigación, donde se estudian parámetros como el género y el formato, la publicidad y la autopromoción o la segmentación de edades y el curriculum escolar se muestra el panorama existente en España en cuanto a canales infantiles; para ello se ha diseñado una metodología de estudio basada en la triangulación de métodos científicos donde convergen diversas técnicas, lo que nos permite obtener una aproximación a la realidad de los Canales Infantiles Politemáticos

  10. Endodontic retreatment of a mandibular first molar with five root canal systems: an important clinical lesson.

    Science.gov (United States)

    Hasan, Muhammad; Umer, Fahad

    2014-03-20

    The objective of root canal treatment is to perform complete debridement of the root canals and subsequent obturation to facilitate healing of periapical pathosis. However, this process becomes complicated with the presence of additional root canal systems. The purpose of the present article is to report successful non-surgical retreatment of a mandibular first molar with five canals. This case report discusses the clinical management of a previously root filled mandibular firstmolar with two missed canal systems; distolingual and an additional mesial canal known as the middle mesial canal. The post-treatment radiographs show successful obturation to length in all canals. The middle mesial canal was found to be associated with mesiolingual canal and categorised as confluent. The configuration of canals in the mesial root was type XV, based on the classification given by Sert and Bayirli. This case report highlights the importance of knowledge and its application in the management of abnormal anatomic variants which play a crucial role in the success of endodontic retreatment.

  11. Bifid mandibular canal: confirmation of limited cone beam CT findings by gross anatomical and histological investigations

    Science.gov (United States)

    Fukami, K; Shiozaki, K; Mishima, A; Kuribayashi, A; Hamada, Y; Kobayashi, K

    2012-01-01

    Objectives The aims of this study were (1) to assess the validity of limited cone beam CT (CBCT) in detecting the distribution of bifid mandibular canals in the retromolar region by comparing its findings with those of panoramic radiography and spiral CT imaging, and (2) to confirm the contents of such canals depicted on limited CBCT images by using gross anatomical and histological methods. Methods Bilateral bifid mandibular canals of a Japanese cadaver were investigated. The canals depicted on panoramic radiography, spiral CT and limited CBCT images were compared. Cross-sectional limited CBCT images of these canals were compared with gross anatomical sections of the mandible and their contents were confirmed histologically. Results The spiral CT and limited CBCT images showed the bilateral bifid mandibular canals in the retromolar region whereas the panoramic radiographs indicated the presence of only the left bifid mandibular canal. The canal distribution was more distinct in the limited CBCT images than in the spiral CT images and the cross-sectional limited CBCT images were consistent with the gross anatomical sections. Histologically, the canals contained several nerve bundles and arteries among which the largest nerve and artery were of a similar size. Conclusion Limited CBCT is valuable for assessing the distribution of bifid mandibular canals. It is clinically significant to accurately localize a bifid mandibular canal of the retromolar region because it contains a nerve bundle and artery. PMID:22116121

  12. The effect of four different irrigation systems in the removal of a root canal sealer.

    Science.gov (United States)

    Grischke, J; Müller-Heine, A; Hülsmann, M

    2014-09-01

    The aim of this study was to compare the efficiency of sonic, ultrasonic, and hydrodynamic devices in the removal of a root canal sealer from the surface and from simulated irregularities of root canals. Fifty-three root canals with two standardized grooves in the apical and coronal parts of longitudinally split roots were covered with AH Plus root canal sealer. Compared were the effects of (control) syringe irrigation, (1) CanalBrush, (2) passive ultrasonic irrigation, (3) EndoActivator, and (4) RinsEndo on the removal of the sealer. The specimens were divided into four groups (N = 12) and one control group (N = 5) via randomization. The amount of remaining sealer in the root canal irregularities was evaluated under a microscope using a 4-grade scoring system, whereas the remaining sealer on the root canal surface was evaluated with a 7-grade scoring system. Passive ultrasonic irrigation is more effective than the other tested irrigation systems or syringe irrigation in removing sealer from root canal walls (p irrigation shows a superior effect on sealer removal from the root canal surface during endodontic retreatment. Cleaning of lateral grooves seems not to be possible with one of the techniques investigated. Incomplete removal of root canal sealer during re-treatment may cause treatment failure. Passive Ultrasonic irrigation seems to be the most effective system to remove sealer from a root canal.

  13. Controlador basado en variables de estado para un Brazo de dos grados de libertad.

    Directory of Open Access Journals (Sweden)

    Edgar Andrés Gutiérrez Cáceres

    2011-05-01

    Full Text Available Este artículo pretende hacer que el control de un brazo robótico con dos grados de libertad, se muestra todas las medidas para analizar el sistema de control y trabajar con variables de estado a partir de las ecuaciones describe el sistema. Inicialmente las ecuaciones son expresadas por una reducción o cambio de orden variable, a continuación, se procede a crear las matrices de variables de estado y, finalmente, determina si el sistema es controlable y observable, para simular en Simulink y luego determinar el comportamiento según el controlador aquí diseñado. Se muestra el continuo mejoramiento y la preocupación por las nuevas técnicas de análisis y sistemas elec trónicos, el grupo VITAL SIGNAL & CONTROL a tomado la iniciativa de utilizar técnicas de procesamiento y dar a conocer sus primeros avances.

  14. Endodontic management of bilateral mandibular canines with an unusual root canal anatomy

    Directory of Open Access Journals (Sweden)

    Sujan Rijal

    2015-01-01

    Full Text Available This case report describes the endodontic management of bilateral mandibular canines with unusual root canal anatomy in a patient. The right mandibular canine had two separate roots (buccal and lingual, each root having a single canal. The left mandibular molar had two separate canals coronally joining into a single canal in the apical 3 rd (Vertucci Type II. While the presence of two roots and two canals in one root is not uncommon, finding a combination of these morphological variations in the same patient has not been reported previously. This emphasizes the perception of the clinician that a given tooth will contain a specific number of roots and/or root canals canal should be changed, and such variations should be kept in mind during the endodontic treatment of permanent mandibular canines.

  15. First Branchial Cleft Fistula Associated with External Auditory Canal Stenosis and Middle Ear Cholesteatoma

    Directory of Open Access Journals (Sweden)

    shahin abdollahi fakhim

    2014-10-01

    Full Text Available Introduction: First branchial cleft anomalies manifest with duplication of the external auditory canal.   Case Report: This report features a rare case of microtia and congenital middle ear and canal cholesteatoma with first branchial fistula. External auditory canal stenosis was complicated by middle ear and external canal cholesteatoma, but branchial fistula, opening in the zygomatic root and a sinus in the helical root, may explain this feature. A canal wall down mastoidectomy with canaloplasty and wide meatoplasty was performed. The branchial cleft was excised through parotidectomy and facial nerve dissection.   Conclusion:  It should be considered that canal stenosis in such cases can induce cholesteatoma formation in the auditory canal and middle ear.

  16. Determinación de defectos de calidad en la canal y carne de cerdo mediante el uso de auditorías

    Directory of Open Access Journals (Sweden)

    Nancy Jerez-Timaure

    2013-01-01

    Full Text Available El objetivo del estudio fue determinar los defectos de calidad en canal y carne de cerdo, utilizando un formato de encuesta, y correlacionando los resultados de la misma con las características de la canal y la carne. La encuesta se aplicó durante el embarque, transporte, desembarque y proceso de beneficio. Se evaluaron cuatro grupos de 50 cerdos, con una frecuencia semanal. La evaluación individual se realizó desde el desembarque, conducción al aturdimiento, insensibilización, desangrado y escaldado. Se determinó el pH y la temperatura (45 min y 24 h, la capacidad de retención de agua, las pérdidas por goteo, el color y los defectos en canal al despiece. Se encontró que el 46.5 % de los cerdos fueron aturdidos incorrectamente, y el 53 % de los animales presentaron signos de sensibilidad al desangrado.Se obtuvieron siete correlaciones canónicas entre dos grupos de variables ("canal" y "beneficio". Las dos primeras correlaciones explicaron (P<0,05 el 61.6 % de la variación. Se comprobó que la colocación de electrodos, parpadeo, vocalización, reflejo de enderezar la cabeza, están altamente correlacionadas con la variable canónica "canal". El pH45min y pH24h, resultaron con mayor índice de correlación con la variable canoníca "beneficio". La fase crítica del proceso fue el aturdimiento, siendo la colocación del electrodo y parpadeo las variables con mayor asociación con las características de calidad. La encuesta constituye una herramienta de fácil uso para monitorear el proceso de embarque, transporte y beneficio de cerdos.

  17. Identificación paramétrica en lazo cerrado de sistema de accionamiento neumático para cilindro de doble efecto

    Directory of Open Access Journals (Sweden)

    Oscar Caldas Flautero

    2013-01-01

    Full Text Available Los modelos matemáticos que permiten comprender un sistema y predecir o simular su comportamiento suelen presentar inconvenientes cuando se cuenta con poca información a priori o se desconocen los parámetros físicos. Por esa razón, en este trabajo se presenta la identificación de sistemas como estrategia para abordar la construcción de modelos dinámicos complejos, proponiendo soluciones para tratar el comportamiento no-lineal de un sistema neumático, representado por un actuador de doble efecto y un par de válvulas proporcionales para el control de la presión de alimentación y el caudal. Se presenta una aproximación almodelomatemático para determinar el orden del sistema, la identificación en lazo abierto y lazo cerrado y la comparación entre modelos de procesosARX yARMAX, con diferente orden, para concluir con simulaciones comparativas entre la respuesta del sistema real y la del identificado.

  18. Dimension, anatomy and morphology of the mesiobuccal root canal system in maxillary molars.

    Science.gov (United States)

    Degerness, Randy A; Bowles, Walter R

    2010-06-01

    To increase our understanding of the root canal system, we examined the mesiobuccal (MB) roots of maxillary first and second molars, which are considered to be one of the most complex root canal systems. Uninstrumented MB roots from 153 teeth were imbedded, sectioned, and observed at 8x using a stereomicroscope for main canal numbers, isthmus presence, and dimensional size of canals and dentin walls. The number of canals observed in maxillary first and second molars was 20% and 38.1% for one canal, 79.8% and 60.3% for two canals, and 1.1% and 1.6% for three canals, respectively. The buccal canal was larger than lingual or middle canals at all levels of the root. The average distance between the two main canals was 1.2 +/- 0.6 mm in first molars and 1.78 +/- 0.6 mm in second molars. Isthmus tissue increased greatly at 3.6 mm from the apex, suggesting optimal root resection at this level. Little differences in thickness between mesial and distal canal walls were seen until reaching the coronal sections of the root where the average canal wall thickness was found to be thinner (33%) on the distal, suggesting a "danger zone" for maxillary molars at a level where the root joins the crown of the tooth. The observations made here provide a more precise understanding of the maxillary MB root system. Orthograde and retrograde root canal therapy might be improved with a comprehensive understanding of pulpal morphology throughout the entire MB root. Copyright 2010 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  19. Assessment of bifid and trified mandicular canals using cone beam computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Rashsyren, Oyuntugs [Dept. of Oral and Maxillofacial Radiology, School of Dentistry, Mongolian National University Medical Science, Ulaanbaatar (United States); Choi, Jin Woo; Han, Won Jeong; Kim Eun Kyung [Dept. of Oral and Maxillofacial Radiology, Dankook University College of Dentistry, Cheonan (Korea, Republic of)

    2014-09-15

    To investigate the prevalence of bifid and trifid mandibular canals using cone-beam computed tomography (CBCT) images, and to measure their length, diameter, and angle. CBCT images of 500 patients, involving 755 hemi-mandibles, were used for this study. The presence and type of bifid mandibular canal was evaluated according to a modified classification of Naitoh et al. Prevalence rates were determined according to age group, gender, and type. Further, their diameter, length, and angles were measured using PACSPLUS Viewer and ImageJ 1.46r. Statistical analysis with chi-squared and analysis of variance (ANOVA) tests was performed. Bifid and trifid mandibular canals were found in 22.6% of the 500 patients and 16.2% of the 755 sides. There was no significant difference between genders and among age groups. The retromolar canal type accounted for 71.3% of the identified canals; the dental canal type, 18.8%; the forward canal type, 4.1%; and the trifid canal type, 5.8%. Interestingly, seven cases of the trifid canal type, which has been rarely reported, were observed. The mean diameter of the bifid and trifid mandibular canals was 2.2 mm and that of the main mandibular canal was 4.3 mm. Their mean length was 16.9 mm; the mean superior angle was 149.2 degrees, and the mean inferior angle was 37.7 degrees. Bifid and trifid mandibular canals in the Korean population were observed at a relatively high rate through a CBCT evaluation, and the most common type was the retromolar canal. CBCT is suggested for a detailed evaluation of bifid and trifid mandibular canals before mandibular surgery.

  20. Penetração intratubular de cimentos endodônticos Intratubular penetration of root canal sealers

    Directory of Open Access Journals (Sweden)

    Gustavo de Deus

    2002-12-01

    Full Text Available Este estudo foi desenvolvido para avaliar a capacidade de penetração de diferentes cimentos endodônticos (Endo Fill, Sealapex, AH Plus e Pulp Canal Sealer nos túbulos dentinários em dentes devidamente modelados e obturados. Foram utilizados 72 incisivos centrais superiores, os quais foram instrumentados no sentido coroa-ápice pela técnica de forças balanceadas. O comprimento de trabalho foi estabelecido a 1 mm do ápice radicular. Durante a limpeza e modelagem, todos os dentes foram irrigados com 10 ml de hipoclorito de sódio a 5,25%. Os dentes foram divididos em 4 grupos, sendo 1 para cada tipo de cimento. Estes grupos foram então subdivididos em função do uso ou não de EDTA a 17% previamente à obturação dos canais radiculares, para a remoção da lama dentinária. Todos os dentes foram obturados pela técnica da onda de condensação com cone médio calibrado. Após obturação, as raízes foram seccionadas no sentido mésio-distal e foi escolhida a secção de melhor qualidade visual. Estas foram então analisadas em microscopia eletrônica de varredura (MEV, sendo o foco de observação sempre a interface dentina/material obturador. Após obtenção das imagens, mensurou-se os prolongamentos dos cimentos para o interior dos túbulos dentinários. O cimento de Rickert (Pulp Canal Sealer apresentou a maior capacidade de penetração nos túbulos dentinários, sendo os piores resultados apresentados pelo grupo em que se utilizou o Sealapex. Os resultados foram avaliados estatisticamente pelo teste de Spearman, o qual mostrou diferença estatisticamente significante (p The purpose of this study was to evaluate the capacity of penetration of four endodontic sealers (Endo Fill, Sealapex, AH Plus and Pulp Canal Sealer into dentinal tubules. Seventy-two extracted human maxillary anterior teeth were utilized in this study. The teeth were cleaned and shaped by means of the balanced-forces technique. The work length was established at 1