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Cardiopulmonary resuscitation (CPR) is an emergency procedure performed on patients during cardiac and respiratory arrest. This procedure externally activates the cardiac and respiratory systems via the delivery of chest compression and artificial ventilation. As the main purpose of CPR is to recirculate the blood flow, prediction of the myocardium behavior has great importance. This prediction allows us to have a better understanding of the needed force to recirculate blood without hurting the heart. Finite element method offer the possibility of noninvasive quantification of myocardial deformation. This method is attractive to use for the assessment of myocardial function. To investigate the behavior of the heart wall, a 3D model of thoracic organs has been prepared using medical images. In this study, to simulate the behavior of different organs, Code-Aster open software is used. For every organ, the material properties are defined. The most important parameters in the study are displacement, normal stress, and Von-Mises stress in the myocardium. Using these parameters, displacement and stress distribution have been predicted. Effects of the applied force on the chest during CPR and deformation of the myocardium have been predicted by the finite element model. A linear deformation is observable for each organ during force application. Besides, the final location of the heart and ribs and also involved parameters in predicting myocardium deformation are extracted from the model simulations. This finite element model enables us to have a good vision of the deformation of the myocardium during CPR. Using this method, it is possible to predict the deformation of every part of the heart, especially right and left ventricles., 9 pages, 9 figures, 1 table

An ostomy is a surgical procedure by which an artificial opening in the abdominal wall, known as a stoma, is created. We assess the effects of stoma location on the abdominal wall mechanics. We perform three-dimensional finite element simulations on an anatomy model which was generated on the basis of medical images. Our simulation methodology is entirely based on open source software. We consider seventeen different locations for the stoma incision (trephine) and we simulate the mechanical response of the abdominal wall when an intraabdominal pressure as high as 20 kPa is applied. We focus on factors related to the risk of parastomal hernia development such as the deformation experienced by the abdominal wall, the stress levels supported by its tissues and the corresponding level of trephine enlargement. No significant dependence was found between stoma location and the levels of abdominal wall deformations or stress supported by tissues, except for the case with a stoma located on the linea alba. Trephine perimeter and area respectively increased by as much as $$44\%$$ 44 % and $$85\%$$ 85 % . The level of trephine deformation depends on stoma location with considerably higher trephine enlargements found in stomas laterally located with respect to the rectus abdominis muscle.

Tradicionalment el fenomen de spin-crossover s’ha estudiat en complexos hexacoordinats de Fe2+. L’objectiu d’aquesta tesi és aprofundir en aquest fenomen en complexos amb metalls de transició menys convencionals i altres nombres de coordinació mitjançant un estudi computacional. El capítol 3 presenta l’estudi d’un compost de ruteni amb capacitat de transferir electrons a molècules acceptores i per tant amb potencials aplicacions en cel•les solars. En els capítols 4 i 5 s’analitzen complexos de Ni porfirina amb biestabilitat i spin-crossover per irradiació amb llum. El capítol 6 tracta dels estats magnètics i d’oxidació de complexos de manganès. El treball estudia les diferències en la fotoquímica d’aquests metalls amb la dels complexos de ferro. L’exemple de la porfirina de Ni funcionalitzada amb un braç fenilazopiridínic dóna informació sobre el mecanisme de spin-crossover dirigit pel lligand amb canvi de coordinació. En els complexos de Mn, l’estabilitat relativa dels estats singlet i triplet depèn del caràcter sigma-donador del lligand axial., Tradicionalmente el fenómeno de spin-crossover se ha estudiado en complejos hexacoordinados de Fe2+. El objetivo de esta tesis es profundizar en este fenómeno en complejos con metales de transición menos convencionales i otros números de coordinación mediante un estudio computacional. El capítulo 3 presenta el estudio de un compuesto de rutenio con capacidad de transferir electrones a moléculas aceptoras y por lo tanto con potenciales aplicaciones en celdas solares. En los capítulos 4 y 5 se analizan complejos de Ni porfirina con spin-crossover después de ser irradiados por luz. El capítulo 6 trata de los estados magnéticos y de oxidación de complejos de manganeso. El trabajo estudia las diferencias en la fotoquímica de estos metales con la de los complejos de hierro. El ejemplo de la porfirina de Ni funcionalizada con un brazo fenilazopiridínico aporta información sobre el mecanismo de spin-crossover dirigido por el ligando con cambio de coordinación. En los complejos de Mn, la estabilidad relativa de los estados singlete y triplete depende del carácter sigma-dador del ligando axial., Spin-crossover phenomenon has traditionally been studied for hexacoordinated Fe2+ complexes. The aim of this thesis is to get insight on this phenomenon in less conventional transition metals and other coordination numbers by means of a computational study. Chapter 3 presents the study of a ruthenium compound with ability to transfer electrons to acceptor molecules and, hence, with potential applications in solar cells. Chapters 4 and 5 analyze Ni porphyrin complexes exhibiting spin-crossover after irradiation with light. Chapter 6 treats the magnetic and oxidation states of manganese complexes. The work studies the differences in the photochemistry of these metals with respect to the iron complexes. The example of Ni porphyrin functionalized with a phenilazopyridine arm helps to understand the mechanism of coordination-induced spin-crossover. In Mn complexes, the relative stability of the singlet and triplet states depends on the sigma-donor character of the axial ligand.