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

A new method for quantitative evaluation of target volume variations in radiotherapy planning

A new method for three-dimensional quantitative evaluation of target volume delineation is presented. It is composed by a new 3D reconstruction method called Origami, based on the combination of two bidimensional analysis of the volume of each organ instead of one 3D analysis, and a 3D description of the error distribution in the space. The Origami method avoid external errors introduced by a 3D rendering and has shown to work correctly in both convex and convex-concave volumes, accurately fitting the contours of the planning study. Its performance has been evaluated comparing it with the Convex Hull algorithm using Delaunay triangulation, resulting in a much more adjusted evaluation. Moreover, Origami computes thousands of control points in less than one second in a common PC

Método de evaluación cuantitativa de algoritmos de registro tridimensional deformable

Se presenta una nueva metodología de evaluación cuantitativa de algoritmos de registro tridimensional deformable basada en las delineaciones de los órganos de interés. Esta metodología ofrece una completa descripción tridimensional del error de registro mediante el cálculo de las distancias entre los volúmenes del órgano de interés en la imagen de referencia y la imagen registrada. El método propuesto ha demostrado la capacidad de trabajar correctamente tanto en volúmenes totalmente convexos como en volúmenes cóncavo-convexos, ajustándose de manera precisa a los volúmenes marcados por el especialista. Además, el alto rendimiento del método permite la rápida evaluación en un gran número de direcciones de control (64800 direcciones en menos de un segundo

Dependence of Induced Biological Damage on the Energy Distribution and Intensity of Clinical Intra-Operative Radiotherapy Electron Beams

The survival fraction of epithelial HaCaT cells was analysed to assess the biological damage caused by intraoperative radiotherapy electron beams with varying energy spectra and intensities. These conditions were achieved by irradiating the cells at different depths in water using nominal 6 MeV electron beams while consistently delivering a dose of 5 Gy to the cell layer. Furthermore, a Monte Carlo simulation of the entire irradiation procedure was performed to evaluate the molecular damage in terms of molecular dissociations induced by the radiation. A significant agreement was found between the molecular damage predicted by the simulation and the damage derived from the analysis of the survival fraction. In both cases, a linear relationship was evident, indicating a clear tendency for increased damage as the averaged incident electron energy and intensity decreased for a constant absorbed dose, lowering the dose rate. This trend suggests that the radiation may have a more pronounced impact on surrounding healthy tissues than initially anticipated. However, it is crucial to conduct additional experiments with different target geometries to confirm this tendency and quantify the extent of this effect

EducaFarma 9.0

Memoria ID-020 Ayudas de la Universidad de Salamanca para la innovación docente, curso 2020-2021

EducaFarma 11.0

Memoria ID2022-036. Ayudas de la Universidad de Salamanca para la innovación docente, curso 2022-2023

Educafarma 10.0

Memoria ID-030. Ayudas de la Universidad de Salamanca para la innovación docente, curso 2021-2022

Handbook of Active Ageing and Quality of Life: From Concepts to Applications

La edición de este libro estuvo a cargo de Fermina Rojo-Pérez y Gloria Fernández-Mayoralas.El documento adjunto contiene la cubierta, portada e índice del libro.This handbook presents an overview of studies on the relationship of active ageing and quality of life. It addresses the new challenges of ageing from the paradigm of positive ageing (active, healthy and successful) for a better quality of life. It provides theoretical perspectives and empirical studies, including scientific knowledge as well as practical experiences about the good ageing and the quality of later life around the world, in order to respond to the challenges of an aged population. The handbook is structured in 4 sections covering theoretical and conceptual perspectives, social policy issues and research agenda, methods, measurement instrument-scales and evaluations, and lastly application studies including domains and geographical contexts.Peer reviewe

Título en español

Yield of taniers on a Corozal clay (Ultisol) decreased with increasing soil acidity from 16.3 t/ha at pH 5.0 with 12% saturation of the CEC with Al, to 4.2 t/ha at pH 4.2 and 70% Al saturation. Similar results were obtained on Corozal clay subsoil. Much lower yields were produced on Coto clay (Oxisol). These yields were lowered only at the highest acidity level, pH 4.5, and 34% Al saturation of the soil CEC. Foliar composition of the taniers was not affected by soil acidity, except that the Ca content was appreciably less at the highest level of acidity on the Corozal soil and subsoil. For all soils combined, pH and percent Al saturation of the soil CEC correlated very closely with yields. Overall yields were close to maximum when the soil had a pH of 5.2 and no exchangeable Al.Se estudió el efecto de los factores de acidez del suelo en la producción y composición foliar de la yautía en dos Ultisol en Corozal y un Oxisol en Isabela. En el suelo Corozal la producción de tubérculos disminuyó cuando el pH del suelo bajó de 4.8, lo que correspondió a 25% de saturación de la capacidad de cambio del suelo con aluminio. Cuando el pH del suelo bajó a 4.2, que corresponde a un 78% de saturación de la capacidad de cambio del suelo con aluminio, la producción fue de solamente un 25% del máximo. La producción de "madres" (cormos) siguió un patrón similar al de los "hijos". El efecto de los factores de acidez en la producción de la yautía creciendo en subsuelo Corozal fue similar a la que creció en el suelo. En el suelo Coto, la producción de hijos fue mucho más baja que en el Corozal y disminuyó solamente cuando la acidez bajó a pH 4.5, lo que corresponde a 34% de saturación de la capacidad de cambio con aluminio. La producción de "madres" fue casi tan alta en el suelo Coto como en el Corozal, sin afectar la acidez. Los rendimientos más altos se obtuvieron cuando el pH del suelo fue de 5.2 o más, a cuya acidez no hay aluminio cambiable en el suelo. A 60% de saturación de los suelos con aluminio, equivalente a pH 4.5, el rendimiento fue alrededor del 50% del máximo