Automated Segmentation of Cerebral Vasculature with Aneurysms in 3DRA and TOF-MRA using Geodesic Active Regions: an Evaluation Study

Purpose: To evaluate the suitability of an improved version of an automatic segmentation method based on geodesic active regions (GAR) for segmenting cerebral vasculature with aneurysms from 3D X-ray reconstruc-tion angiography (3DRA) and time of °ight magnetic resonance angiography (TOF-MRA) images available in the clinical routine.Methods: Three aspects of the GAR method have been improved: execution time, robustness to variability in imaging protocols and robustness to variability in image spatial resolutions. The improved GAR was retrospectively evaluated on images from patients containing intracranial aneurysms in the area of the Circle of Willis and imaged with two modalities: 3DRA and TOF-MRA. Images were obtained from two clinical centers, each using di®erent imaging equipment. Evaluation included qualitative and quantitative analyses ofthe segmentation results on 20 images from 10 patients. The gold standard was built from 660 cross-sections (33 per image) of vessels and aneurysms, manually measured by interventional neuroradiologists. GAR has also been compared to an interactive segmentation method: iso-intensity surface extraction (ISE). In addition, since patients had been imaged with the two modalities, we performed an inter-modality agreement analysis with respect to both the manual measurements and each of the two segmentation methods. Results: Both GAR and ISE di®ered from the gold standard within acceptable limits compared to the imaging resolution. GAR (ISE, respectively) had an average accuracy of 0.20 (0.24) mm for 3DRA and 0.27 (0.30) mm for TOF-MRA, and had a repeatability of 0.05 (0.20) mm. Compared to ISE, GAR had a lower qualitative error in the vessel region and a lower quantitative error in the aneurysm region. The repeatabilityof GAR was superior to manual measurements and ISE. The inter-modality agreement was similar between GAR and the manual measurements. Conclusions: The improved GAR method outperformed ISE qualitatively as well as quantitatively and is suitable for segmenting 3DRA and TOF-MRA images from clinical routine.

Dynamic estimation of three-dimensional cerebrovascular deformation from rotational angiography

Purpose: The objective of this study is to investigate the feasibility of detecting and quantifying 3D cerebrovascular wall motion from a single 3D rotational x-ray angiography (3DRA) acquisition within a clinically acceptable time and computing from the estimated motion field for the further biomechanical modeling of the cerebrovascular wall. Methods: The whole motion cycle of the cerebral vasculature is modeled using a 4D B-spline transformation, which is estimated from a 4D to 2D + t image registration framework. The registration is performed by optimizing a single similarity metric between the entire 2D + t measured projection sequence and the corresponding forward projections of the deformed volume at their exact time instants. The joint use of two acceleration strategies, together with their implementation on graphics processing units, is also proposed so as to reach computation times close to clinical requirements. For further characterizing vessel wall properties, an approximation of the wall thickness changes is obtained through a strain calculation. Results: Evaluation on in silico and in vitro pulsating phantom aneurysms demonstrated an accurate estimation of wall motion curves. In general, the error was below 10% of the maximum pulsation, even in the situation when substantial inhomogeneous intensity pattern was present. Experiments on in vivo data provided realistic aneurysm and vessel wall motion estimates, whereas in regions where motion was neither visible nor anatomically possible, no motion was detected. The use of the acceleration strategies enabled completing the estimation process for one entire cycle in 5-10 min without degrading the overall performance. The strain map extracted from our motion estimation provided a realistic deformation measure of the vessel wall. Conclusions: The authors' technique has demonstrated that it can provide accurate and robust 4D estimates of cerebrovascular wall motion within a clinically acceptable time, although it has to be applied to a larger patient population prior to possible wide application to routine endovascular procedures. In particular, for the first time, this feasibility study has shown that in vivo cerebrovascular motion can be obtained intraprocedurally from a 3DRA acquisition. Results have also shown the potential of performing strain analysis using this imaging modality, thus making possible for the future modeling of biomechanical properties of the vascular wall.

Three-dimensional morphological analysis of intracranial aneurysms: a fully automated method for aneurysm sac isolation and quantification

Morphological descriptors are practical and essential biomarkers for diagnosis andtreatment selection for intracranial aneurysm management according to the current guidelinesin use. Nevertheless, relatively little work has been dedicated to improve the three-dimensionalquanti cation of aneurysmal morphology, automate the analysis, and hence reduce the inherentintra- and inter-observer variability of manual analysis. In this paper we propose a methodologyfor the automated isolation and morphological quanti cation of saccular intracranial aneurysmsbased on a 3D representation of the vascular anatomy.

Sebastià Juan Arbó, autotraductor: de terres de l'Ebre (1932) a Tierras del Ebro (1940)

Sebastià Juan Arbó (1902-1984) era un escriptor en llengua catalana fins a la Guerra Civil espanyola. Arran del desenllaç de la guerra, Arbó va esdevenir un escriptor tant en llengua catalana com en llengua castellana. Aquest pas d’una llengua a una altra va tenir un pas intermedi: l’autotraducció. A partir de la seva primera autotraducció al castellà (Tierras del Ebro, 1940), Sebastià Juan Arbó es va introduir en les lletres castellanes. Aquesta tasca autotraductora, que encetà el 1940, no l’abandonà en la resta de la seva obra catalana i mai no l’exercí en la seva obra escrita originalment en llengua castellana.Amb aquest treball de recerca es vol establir, en primer lloc, un mètode d’anàlisi per a l’autotraducció de Terres de l’Ebre, de Sebastià Juan Arbó, que pugui ser exportable a l’anàlisi d’altres autotraduccions, i, en segon lloc, analitzar un fragment de les primeres edicions en català (1932) i castellà (1940) de Terres de l’Ebre, que permeti reconèixer-hi les tendències autotraductores de Sebastià Juan Arbó.

El aprendiz de rapsoda, o de cuando Homero cruzó la laguna estigia (Lucianus, Cont. 7)

In Charon or the Inspectors we find the ferryman of the underworld on earth, talking to the god Hermes about wealth, happiness, and the vain human striving for material goods. The piece has been considered to be an example of Menippean satire inside the corpus of Lucian"s works. Homeric poetry is always in the background. Lucian uses Homeric verses, or rather, verses structured in the Homeric manner, to formulate his critical view of the mortal world; in addition, he puts these verses into the mouth of a character who must temporarily give up his job as a ferryman in order to practise the art of rhapsody. This paper analyses a textual problem: the two variants in Cont. 7 referring to Homer in the manuscript tradition. In a context in which Lucian wants to make fun not just of foolish humans but also of the Greek poet par excellence, the reading of the ueteres seems more appropriate because it illustrates better Lucian"s parodic intention in recalling Homer and in trying to adapt form and content to the Greek tradition.

Reduced microwave losses of YBa2Cu3O7_thin films on electro-optic LiNbO3 crystals

We report on the growth of epitaxial YBa2Cu3O7 thin films on X-cut LiNbO3 single crystals. The use of double CeO2/YSZ buffer layers allows a single in-plane orientation of YBa2Cu3O7, and results in superior superconducting properties. In particular, surface resistance Rs values of 1.4 m¿ have been measured at 8 GHz and 65 K. The attainment of such low values of Rs constitutes a key step toward the incorporation of high Tc materials as electrodes in photonic and acoustic devices.

Cultura y espiritualidad en la edad moderna valenciana: Juan de Juanes y el ostensorio bifaz de la iglesia parroquial de San Andrés de L'Alcúdia.

En este artículo, partiendo de las pinturas de Juan de Juanes en l¿Alcúdia, analizamos las cuestiones sociales que pudieron incidir en su producción artística, iconografía y difusión dentro del ámbito valenciano. La posible influencia del erasmismo, la filosofía intimista, la cristología de Eiximenis o el adoctrinamiento a los moriscos son algunos aspectos sobre los que centramos nuestra reflexión.

Contreras Cortés, Francisco y Cámara Serrano, Juan Antonio: La jerarquización social en la Edad del Bronce del Alto Guadalquivir (España). El poblado de Peñalosa (Baños de la Encina, Jaén)

La denominada cultura argárica ha sido desde siempre uno de los focos más atractivos de la Prehistoria peninsular. El libro que tenemos entre las manos aporta un grano de arena más al conocimiento de esta cultura, pero atendiendo a uno de los grupos geográficamente más periféricos, lo que complementa los trabajos que desde mucho tiempo atrás se vienen realizando en diversos puntos del SE peninsular, área nuclear de este fenómeno.

Pere Bosch Gimpera y Juan Cabré. La pugna por el control de las excavaciones en San Antonio de Calaceite y el Bajo Aragón (1914-1916) y su influencia en la creación del Servei d"Investigacions Arqueològiques del IEC

En la historiografía de la investigación sobre la cultura ibérica, el poblado de San Antonio el Pobre (Calaceite) va indeleblemente unido a las intervenciones del Institut d¿Estudis Catalans (IEC) y a la figura de Pere Bosch Gimpera, sin duda el prehistoriador español de mayor prestigio hasta el final de la guerra civil. Sin embargo, es significativo que dicho conocimiento se deba más a trabajos aislados y a la recuperación de sus diarios de excavación realizada por Francisca Pallarés Salvador en 1958, que a la publicación de una serie de monografías que recogiera sus trabajos en el área entre 1914 y 1923.

Un conjunto de estructuras de combustión en la H.88/21 del poblado protohistórico del Alto de la Cruz (Cortes, Navarra)

La secuencia cronoestratigráfica del poblado de la Primera Edad del Hierro del Alto de la Cruz (Cortes de Navarra) constituye un punto de referencia básico para la estructuración del poblamiento en el valle medio del Ebro. Se analiza el tipo constructivo de la fase más antigua del mismo y, en especial, un conjunto de estructuras de combustión documentadas en la H.88/21.

El profesor Juan Maluquer de Motes y los estudios sobre Tartessos

La investigación sobre Tartessos fue siempre una de la líneas de trabajo favoritas del Prof. Maluquer de Motes, quien, en el momento de definir la que constituyó su última gran línea de investigación, el programa PIP (Programa de Investigación Protohistórica), prestó una especial atención al estudio de las comunidades prerromanas de Andalucía y Extremadura, especialmente tartesias e iberas, destacando entre los trabajos publicados en este marco las intervenciones de Ma . E. Aubet en la necrópolis de Setefilla (Lora del Río, Sevilla), y del propio Maluquer de Motes en el palacio-santuario de Cancho Roano (Zalamea de la Serena, Badajoz).

Réplica a las objeciones presentadas por el Sr. Juan Ullastre a la parte gráfica que ilustra un artículo de geofísica del Berguedá y Solsonés (Pre-Pirineo Catalán)

El comentario que con el título de 'Objeciones a la parte gráfica .que ilustra un artículo de geofísica del Berguedá y Solsonés' realiza J.Ullastre a nuestro artículo 'Aportaciones de la prospección geofísica al estudio del subsuelo del Berguedá y Solsonés' publicado en el volumen 27 de esta revista dedicado en homenaje al Dr Oriol Riba, presenta algunos aspectos formales y otros de fondo que merece la pena puntualizar.

"Poner riquezas en mi entendimiento": Sor Juana Inés de la Cruz y Sor Teresa de Cartagena

This article aims to show the resemblances that we can find between Admiraçión operum Dey written by Teresa de Cartagena in the mid-XVth century and Respuesta de sor Filotea de la Cruz written by Sor Juana Inés de la Cruz two hundred years later. Both works are two epistles where the female's intellectual capacity to know and to write is defended by a nun who was received critized for a former work. The religious Teresa de Cartagena ¿converse bishop Pablo Cartagena's granddaughter¿ wrote a moral essay that surprised male readers who considered that the text was a plagiarism. On the other hand, the hieronymite sister sor Juana Inés was reproached by a clergyman for having written the polemic treatise on theology Carta Atenagórica.

"Poner riquezas en mi entendimiento": Sor Juana Inés de la Cruz y Sor Teresa de Cartagena

This article aims to show the resemblances that we can find between Admiraçión operum Dey written by Teresa de Cartagena in the mid-XVth century and Respuesta de sor Filotea de la Cruz written by Sor Juana Inés de la Cruz two hundred years later. Both works are two epistles where the female's intellectual capacity to know and to write is defended by a nun who was received critized for a former work. The religious Teresa de Cartagena ¿converse bishop Pablo Cartagena's granddaughter¿ wrote a moral essay that surprised male readers who considered that the text was a plagiarism. On the other hand, the hieronymite sister sor Juana Inés was reproached by a clergyman for having written the polemic treatise on theology Carta Atenagórica.