2,337 research outputs found
Positional vertigo afterwards maxillary dental implant surgery with bone regeneration
Benign paroxysmal positional vertigo (BPPV) is the most common form of vertigo. It is caused by loose otoconia from the utricle which, in certain positions, displaced the cupula of the posterior semicircular canal. BPPV most often is a result of aging. It also can occur after a blow to the head. Less common causes include a prolonged positioning on the back (supine) during some surgical procedures. Additionally one can include in this ethiopathogenesis the positioning required during the maxillary dental implant surgery with bone regeneration related to a forced head positioning and inner ear trauma induced by dental turbine noise working in the maxillary bone. Two cases of patients who suffered BPPV after undergoing maxillary dental implant with bone regeneration procedures are reported. Diagnosis and treatment are also described
Evolución del agua residual depurada durante su transporte por tubería
Se realiza un estudio de la evolución del agua residual depurada en la Estación Depuradora de Aguas Residuales de Santa Cruz de Tenerife, a lo largo de la conducción de transporte por gravedad de 61 km de longitud y 60 cm de diámetro, que une el depósito regulador de El Tablero con la Balsa del Valle de San Lorenzo. Se realiza un estudio de la evolución de las condiciones sépticas y la generación de sulfuro durante el transporte del agua residual depurada con baja carga orgánica, obteniéndose dos ecuaciones cinéticas en función de la DQO total y soluble. Asimismo, se ha encontrado una relación entre el potencial de ;oxido-reducción y concentración de sulfuro. También se estudia la influencia de la introducción de agua blanca, saturada en oxígeno disuelto, en el punto kilométrico 10 de la conducción de transporte, la cual afecta a las condiciones sépticas del agua residual, inhibiendo la generación de sulfuro, y favoreciendo la aparición de un proceso de nitrificación, seguido de una posterior desnitrificación, de la que se realiza un estudio cinético, obteniendo un orden de reacción 1 para las condiciones que se tienen en el sistema. También se ha podido obtener la constante de desnitrificación k20 para una reacción de primer orden a 20grados
USING ATLAS.TI FOR EXTRACTING THE SOCIAL REPRESENTATION OF KIDNAPPING IN COLOMBIA IN THE ONLINE MEDIA Using ATLAS.ti For Extracting The Social Representation Of Kidnapping In Colombia In The Online Media
Abstract The article begins by briefly describing what social representation is and introducing the topic of study. The focus however is on the description of how ATLAS.ti was used in the process of analyzing a large volume of data encom passing a period of 6 years including text, image and video documents. Described are the process of coding and the various uses of the network view function including the formation of hypertext and the development of conceptual network views
Using ATLAS.ti for extracting the social representation of kidnapping in Colombia in the online media
The article begins by briefly describing what social representation is and introducing the topic of study. The focus however is on the description of how ATLAS.ti was used in the process of analyzing a large volume of data encom-passing a period of 6 years including text, image and video documents. Described are the process of coding and the various uses of the network view function including the formation of hypertext and the development of conceptual network views
La evolución de una red de venas de yeso en contextos tectónicos compresivos: El caso del anticlinorio del Montsant (NE España)
The Montsant anticlinorium is part of the Pàndols-Cavalls-Montsant tectonic line situated in the southwestern area of the Catalan Coastal Ranges, adjacent to the contact with the Tertiary Ebro Basin. We have interpreted this Alpine structure as a triangular type I zone with two opposite faults. The centre of the anticlinorium is formed by middle Muschelkalk facies with intensively deformed gypsum layers and an intensively deformed zone with an associated framework of satin spar gypsum veins. A field structural analysis reveals that there are two sets of veins: one associated with a pre-folding stage (before the Alpine orogeny), and another one related to the development of the Montsant anticlinorium, and therefore syn-folding (and Alpine in age)El anticlinorio del Montsant forma parte de la línea tectónica de PándolsCavalls-Montsant, situada al Suroeste de la Cordillera Costera Catalana, y adyacente al contacto con la Cuenca del Ebro. Esta estructura Alpina se interpreta como una zona triangular de Tipo I con dos flancos opuestos. El centro del anticlinorio está formado por facies del Muschelkalk medio con capas de yeso altamente deformadas formando una red de venas de yeso de tipo satin spar. Mediante un análisis estructural de campo hemos identificado dos conjuntos de venas: uno asociado a la etapa previa al plegamiento (antes de la orogenia Alpina) y el otro asociado a la formación del anticlionorio del Montsant durante la orogenia Alpin
Segmentación automática de aneurismas aórticos abdominales a partir de imágenes de resonancia magnética basada en modelos activos de forma y modelos de textura
Se presenta un algoritmo semiautomático de segmentación de aneurismas aórticos abdominales (AAA) basado en modelos activos de forma (ASM) y modelos de textura. La información de textura viene dada por un conjunto de cuatro imágenes 3D de resonancia magnética (RM) compuestas por cortes axiales de la zona abdominal. En estas imágenes son visibles la luz aórtica, la pared aórtica y el trombo intraluminal (ILT). Dado el tamaño limitado del conjunto de imágenes de RM, se han implementado un ASM que capture las características específicas del conjunto de entrenamiento compuesto por 35 imágenes de tomografía axial computarizada (CTA), de modo que la variación de forma pueda ser adecuadamente caracterizada. La textura se caracteriza a partir de las imágenes de RM. Para la evaluación del algoritmo se ha llevado a cabo una validación cruzada dejando uno fuera sobre el conjunto de imágenes de RM
A new geometrical method for 3D evaluation of non-rigid registration methods for radiotherapy in prostate cancer
Three-dimensional conformal radiotherapy aims at delivering a high dose of radiation to the tumour, while sparing the surrounding normal tissue to a maximum extent. Image registration is an essential tool for monitoring radiation therapies, since allows morphological comparisons in presence of anatomic variations. The evaluation of non-rigid registration methods is very complicated owe to the absence of a known pointwise correspondence. The use of analysis of variations in target volume delineations has been proposed in the past for the evaluation of non-rigid registration methods. Delineation of the target volume is usually accomplished by outlining the contour of the volume in each separate tomographic slice. In the studies of reference, the 3D surface is rendered from the contours by means of a Delauney triangulation. This geometrical method only works correctly for convex structures. However the volumes involved on pelvic anatomy, such as bladder or prostate including the seminal vesicles, have relevant concavities that introduce a huge error in the evaluation. A new geometrical method for the evaluation of convex-concave target volumes delineation is proposed
Automatic segmentation of abdominal aortic aneurysm from medical images based on active shape models and texture models
A semi-automatic segmentation algorithm for abdominal aortic aneurysms (AAA), and based on Active Shape Models (ASM) and texture models, is presented in this work. The texture information is provided by a set of four 3D magnetic resonance (MR) images, composed of axial slices of the abdomen, where lumen, wall and intraluminal thrombus (ILT) are visible. Due to the reduced number of images in the MRI training set, an ASM and a custom texture model based on border intensity statistics are constructed. For the same reason the shape is characterized from 35-computed tomography angiography (CTA) images set so the shape variations are better represented. For the evaluation, leave-one-out experiments have been held over the four MRI set
Nivmar: a storm surge forecasting system for Spanish waters
In this paper, a storm surge prediction system for the Spanish Waters is presented. The system, named Nivmar, is based on the ocean circulation Hamsom model and on the harmonical prediction of tides computed from data measured by the tide gauge network Redmar, managed by Puertos del Estado. Nivmar is executed twice a day, running Hamsom forced by meteorological fields derived from the INM (Instituto Nacional de Meteorología) operational application of Hirlam atmospheric model. Data from Redmar tide gauges is used to to forecast the tidal elevations, to validate the system and to perform data assimilation, correcting systematic errors in the mean sea level due to physicals processes that are not included in the ocean model (i. e. steric height). The forecast horizon is 48 hours. In order to validate the system with measured data from Redmar a very stormy 5 months period was selected. Results from this test (November 95 to March 96) are presented. Data from this experiment shown that Nivmar is able to correctly predict sea level in the region. A simple data assimilation scheme for sea level is described and results from its application are studied. Finally, special focus is made in future plans and potential developments and applications of the system.No disponibl
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