"Busco adivinar quién soy, además de yo mismo": la identidad literaria de Benjamín Prado en su trayectoria poética

Reseña literaria sobre Ruiz, Julia. La voz de la escritura. Madrid: Visor, 201

A multi-method approach towards understanding the pathophysiology of aortic dissections – the complementary role of in-silico, in-vitro and in-vivo information

Management and follow-up of chronic aortic dissections continues to be a clinical challenge due to progressive aortic dilatation. To predict dilatation, guidelines suggest follow-up of the aortic diameter. However, dilatation is triggered by haemodynamic parameters (pressure and wall shear stresses (WSS)), and geometry of false (FL) and true lumen (TL). We aimed at a better understanding of TL and FL haemodynamics by performing in-silico (CFD) and in-vitro studies on an idealized dissected aorta and compared this to a typical patient. We observed an increase in diastolic pressure and wall stress in the FL and the presence of diastolic retrograde flow. The inflow jet increased WSS at the proximal FL while a large variability in WSS was induced distally, all being risk factors for wall weakening. In-silico, in-vitro and in-vivo findings were very similar and complementary, showing that their combination can help in a more integrated and extensive assessment of aortic dissections, improving understanding of the haemodynamic conditions and related clinical evolution

Validation of numerical flow simulations against in vitro phantom measurements in different type B aortic dissection scenarios

An aortic dissection (AD) is a serious condition defined by the splitting of the arterial wall, thus generating a secondary lumen [the false lumen (FL)]. Its management, treatment and follow-up are clinical challenges due to the progressive aortic dilatation and potentially severe complications during follow-up. It is well known that the direction and rate of dilatation of the artery wall depend on haemodynamic parameters such as the local velocity profiles, intra-luminal pressures and resultant wall stresses. These factors act on the FL and true lumen, triggering remodelling and clinical worsening. In this study, we aimed to validate a computational fluid dynamic (CFD) tool for the haemodynamic characterisation of chronic (type B) ADs. We validated the numerical results, for several dissection geometries, with experimental data obtained from a previous in vitro study performed on idealised dissected physical models. We found a good correlation between CFD simulations and experimental measurements as long as the tear size was large enough so that the effect of the wall compliance was negligible.Postprint (published version

Enhancing Drought Tolerance in Canola, Brassica napus

With the ever-increasing occurrences and intensities of drought relating to global climate change (Cook et al. 2014, Singh et al. 2015) crops are negatively affected, limiting the ability for high yields. One such crop is canola, Brassica napus. Canola is a key crop plant in some of the world\u27s top industries, including food and renewable energy. Unfortunately, canola is not a drought tolerant plant, which can impact its supply of food, feed, and research into renewable energy (Zhu et al., 2016, Wang et al. 2016, Tarinejad et al., 2013). Because of these factors it is vital to transform canola into a drought tolerant crop plant. By using agrobacterium mediated hypocotyl explants transformation to place the KfNAC83 vector into the canola genome, we have the potential to produce the highest yield of drought tolerant canola. Previous research has shown increased drought tolerance and biomass mass growth when overexpressed in Arabidopsis thaliana (Amin et al. 2019). This is done by the process of excising hypocotyl explants and preculturing them. Then the explants are inoculated with agrobacterium suspension and returned to a callus induction medium for cocultivation. Once lines of transgenic canola carrying the KfNAC83 TF are produced, we will assay the transgenic canola for drought tolerance. Obtaining the genetically modified, drought tolerant plant, might be advantageous in the food and renewable energy industries in a projected drier environment

Analysis of the haemodynamic and biomechanical properties of the lumina in aortic dissections using an integrated approach focussing on the complementary value of in-silico, in-vitro and invivo assessments

El seguimiento y el manejo de disecciones aórticas de tipo B siguen siendo un gran reto en la práctica clínica. En la fase aguda, la disección aórtica de tipo B es en general menos letal que la disección de tipo A y es tratada médicamente. Sin embargo, una disección de tipo A generalmente persiste en una de tipo B en más del 70% de los casos después de superar la fase aguda y los pacientes con disección aórtica de tipo B tienen una alta mortalidad durante la fase crónica (30-50% a los 5 años), principalmente debido a la dilatación progresiva de la aorta y subsecuente ruptura aórtica. Actualmente, la evaluación y el seguimiento clínicos por imagen (sobre todo basados en la cuantificación de los cambios del diámetro aórtico) presentan serias limitaciones para un manejo óptimo, sumado al hecho de que cada paciente muestra diferencias considerables en la evolución de la enfermedad y por lo tanto, en el pronóstico. Además, la cirugía abierta o endovascular han demostrado no ser óptimas en todos los pacientes, debido a los riesgos adicionales de intervención. Por lo tanto, a pesar de los importantes avances en el diagnóstico por imagen, aún sigue siendo difícil de realizar la estratificación individual de riesgo, encontrando un balance entre el tratamiento médico y quirúrgico para optimizar los resultados en un paciente específico. Por lo tanto, es crucial la cuantificación de marcadores que determinarán la dilatación aórtica progresiva y posterior ruptura, identificando así los pacientes que presentan un bajo riesgo para ser tratados médicamente y reconocer a aquellos que se beneficiarán de una intervención quirúrgica a pesar de los riesgos asociados con el procedimiento. La realización de esta tesis se basa en la hipótesis de que la dilatación aórtica progresiva, en pacientes con disecciones aórticas crónicas, está determinada por factores anatómicos, tales como la comunicación interluminal y la incidencia de ramas laterales en la luz falsa; factores biomecánicos, como la elasticidad de la pared aórtica; y estímulos mecánicos, tales como las presiones y los flujos intraluminales. Por lo tanto, la contribución principal de esta tesis es la propuesta de un enfoque integrado para comprender, en el ámbito de las disecciones aórticas crónicas, la dilatación aórtica y los fenómenos complejos de flujo, centrándose en la información y el conocimiento complementarios que es posible obtener mediante la combinación de enfoques in-vivo, in-vitro e in-silico. Los diferentes enfoques son utilizados para: 1) Determinar la relación existente entre los parámetros geométricos (tamaño, número y localización de las puertas de comunicación e incidencia de ramas laterales comunicantes con la luz falsa) y biomédicos (elasticidad de la pared) potencialmente relacionados con la dilatación aórtica severa y la determinación de flujos y presiones intraluminales resultantes; 2) Caracterizar la hemodinámica intraluminal en disecciones aórticas; 3) Comprender los mecanismos subyacentes en el fenómeno hemodinámico en disecciones aórticas.The follow-up and management of chronic type B aortic dissections continue being highly challenging in clinical practice. In the acute phase, an acute type B aortic dissection is in general less lethal than a type A dissection and medically treated. However, a type A dissection usually converts into a type B dissection in more than 70% of cases after overcoming its acute phase and patients with type B aortic dissection have high mortality during the chronic phase (30-50% at 5 years), mainly due to the progressive dilatation of the aorta, potentially resulting in aortic rupture. Currently, image-based and clinical assessment and follow-up (mainly quantifying changes in diameters) have serious limitations for optimal management, adding to the fact that individual patients show considerable difference in the disease evolution and thus prognosis. Additionally, open surgery or endovascular treatment has shown to be not optimal in each individual due to the additional interventional risks. Therefore, in spite of important advances in image-based diagnosis of this disease, it remains difficult to perform individual risk stratification, balancing medical and surgical strategies to optimise the outcome in a given patient. Consequently, it is crucial to quantify the markers that will determine progressive aortic dilatation and further rupture, thus identifying patients that pose low risks on medical treatment and recognise individuals that will benefit from an intervention despite the risks associated with the procedure. This thesis builds upon the hypothesis that progressive aortic dilatation in patients with chronic aortic dissections is determined by anatomic-geometrical configurations, such as interluminal communication and incidence of side branches in the false lumen; biomechanical factors, such as wall compliance; and mechanical stimuli, such as intraluminal pressures and flows. Hence, the main contribution of this thesis is the proposal of an integrated approach to understand aortic dilatation and the associated complex flow phenomena in the setting of chronic aortic dissections, focussing on the complementary information and knowledge that can be obtained by combining in-vitro, in-silico and in-vivo data. These different approaches are used to: 1) Gain insight into the relationship between the potential geometrical (tear size, number and location and incidence of visceral side branches originating from the false lumen) and biomechanical (wall compliance) parameters of severe aortic enlargement and the induced intraluminal flows and pressures. 2) Characterize intraluminal haemodynamic in aortic dissections. 3) Better understand the mechanisms underlying haemodynamic phenomena in aortic dissections

A web-based tool for cardiac dyssynchrony assessment on ultrasound data

Comunicació presentada al congrés Eurographics Workshop on Visual Computing for Biology and Medicine que va tenir lloc el 7 i 8 de setembre a Bremen, Alemanya.Cardiac resynchronization therapy (CRT) is a broadly used therapy in patients that suffers from heart failure (HF). The positive outcome of CRT depends strongly on the parameters criteria used to select patients and a lot of research has been done to introduce new and more reliable parameters. In this paper we propose an interactive tool to perform visual assessment and measurements on cardiac ultrasound images of patient with cardiac dyssynchrony. The tool is developed as a web application, allowing doctors to remotely access images and measurements.The authors acknowledge the European Union’s Seventh Framework Programme for research, technological development and demonstration (VP2HF FP7-2013-611823 and MEDIA FP7- HEALTH- 2010-261409), the Spanish Ministry of Economy and Competitiveness (TIN2012-35874) and the Maria de Maeztu Units of Excellence Programme (MDM-2015-0502)

Validation of numerical flow simulations against in vitro phantom measurements in different type B aortic dissection scenarios

An aortic dissection (AD) is a serious condition defined by the splitting of the arterial wall, thus generating a secondary lumen [the false lumen (FL)]. Its management, treatment and follow-up are clinical challenges due to the progressive aortic dilatation and potentially severe complications during follow-up. It is well known that the direction and rate of dilatation of the artery wall depend on haemodynamic parameters such as the local velocity profiles, intra-luminal pressures and resultant wall stresses. These factors act on the FL and true lumen, triggering remodelling and clinical worsening. In this study, we aimed to validate a computational fluid dynamic (CFD) tool for the haemodynamic characterisation of chronic (type B) ADs. We validated the numerical results, for several dissection geometries, with experimental data obtained from a previous in vitro study performed on idealised dissected physical models. We found a good correlation between CFD simulations and experimental measurements as long as the tear size was large enough so that the effect of the wall compliance was negligible

Analysis of the haemodynamic and biomechanical properties of the lumina in aortic dissections using an integrated approach focussing on the complementary value of in-silico, in-vitro and invivo assessments

El seguimiento y el manejo de disecciones aórticas de tipo B siguen siendo un gran reto en la práctica clínica. En la fase aguda, la disección aórtica de tipo B es en general menos letal que la disección de tipo A y es tratada médicamente. Sin embargo, una disección de tipo A generalmente persiste en una de tipo B en más del 70% de los casos después de superar la fase aguda y los pacientes con disección aórtica de tipo B tienen una alta mortalidad durante la fase crónica (30-50% a los 5 años), principalmente debido a la dilatación progresiva de la aorta y subsecuente ruptura aórtica. Actualmente, la evaluación y el seguimiento clínicos por imagen (sobre todo basados en la cuantificación de los cambios del diámetro aórtico) presentan serias limitaciones para un manejo óptimo, sumado al hecho de que cada paciente muestra diferencias considerables en la evolución de la enfermedad y por lo tanto, en el pronóstico. Además, la cirugía abierta o endovascular han demostrado no ser óptimas en todos los pacientes, debido a los riesgos adicionales de intervención. Por lo tanto, a pesar de los importantes avances en el diagnóstico por imagen, aún sigue siendo difícil de realizar la estratificación individual de riesgo, encontrando un balance entre el tratamiento médico y quirúrgico para optimizar los resultados en un paciente específico. Por lo tanto, es crucial la cuantificación de marcadores que determinarán la dilatación aórtica progresiva y posterior ruptura, identificando así los pacientes que presentan un bajo riesgo para ser tratados médicamente y reconocer a aquellos que se beneficiarán de una intervención quirúrgica a pesar de los riesgos asociados con el procedimiento. La realización de esta tesis se basa en la hipótesis de que la dilatación aórtica progresiva, en pacientes con disecciones aórticas crónicas, está determinada por factores anatómicos, tales como la comunicación interluminal y la incidencia de ramas laterales en la luz falsa; factores biomecánicos, como la elasticidad de la pared aórtica; y estímulos mecánicos, tales como las presiones y los flujos intraluminales. Por lo tanto, la contribución principal de esta tesis es la propuesta de un enfoque integrado para comprender, en el ámbito de las disecciones aórticas crónicas, la dilatación aórtica y los fenómenos complejos de flujo, centrándose en la información y el conocimiento complementarios que es posible obtener mediante la combinación de enfoques in-vivo, in-vitro e in-silico. Los diferentes enfoques son utilizados para: 1) Determinar la relación existente entre los parámetros geométricos (tamaño, número y localización de las puertas de comunicación e incidencia de ramas laterales comunicantes con la luz falsa) y biomédicos (elasticidad de la pared) potencialmente relacionados con la dilatación aórtica severa y la determinación de flujos y presiones intraluminales resultantes; 2) Caracterizar la hemodinámica intraluminal en disecciones aórticas; 3) Comprender los mecanismos subyacentes en el fenómeno hemodinámico en disecciones aórticas.The follow-up and management of chronic type B aortic dissections continue being highly challenging in clinical practice. In the acute phase, an acute type B aortic dissection is in general less lethal than a type A dissection and medically treated. However, a type A dissection usually converts into a type B dissection in more than 70% of cases after overcoming its acute phase and patients with type B aortic dissection have high mortality during the chronic phase (30-50% at 5 years), mainly due to the progressive dilatation of the aorta, potentially resulting in aortic rupture. Currently, image-based and clinical assessment and follow-up (mainly quantifying changes in diameters) have serious limitations for optimal management, adding to the fact that individual patients show considerable difference in the disease evolution and thus prognosis. Additionally, open surgery or endovascular treatment has shown to be not optimal in each individual due to the additional interventional risks. Therefore, in spite of important advances in image-based diagnosis of this disease, it remains difficult to perform individual risk stratification, balancing medical and surgical strategies to optimise the outcome in a given patient. Consequently, it is crucial to quantify the markers that will determine progressive aortic dilatation and further rupture, thus identifying patients that pose low risks on medical treatment and recognise individuals that will benefit from an intervention despite the risks associated with the procedure. This thesis builds upon the hypothesis that progressive aortic dilatation in patients with chronic aortic dissections is determined by anatomic-geometrical configurations, such as interluminal communication and incidence of side branches in the false lumen; biomechanical factors, such as wall compliance; and mechanical stimuli, such as intraluminal pressures and flows. Hence, the main contribution of this thesis is the proposal of an integrated approach to understand aortic dilatation and the associated complex flow phenomena in the setting of chronic aortic dissections, focussing on the complementary information and knowledge that can be obtained by combining in-vitro, in-silico and in-vivo data. These different approaches are used to: 1) Gain insight into the relationship between the potential geometrical (tear size, number and location and incidence of visceral side branches originating from the false lumen) and biomechanical (wall compliance) parameters of severe aortic enlargement and the induced intraluminal flows and pressures. 2) Characterize intraluminal haemodynamic in aortic dissections. 3) Better understand the mechanisms underlying haemodynamic phenomena in aortic dissections

Hemodynamics in aortic regurgitation simulated using a computational cardiovascular system model

The influence of left ventricular and aortic tissue properties on hemodynamics in patients with aortic regurgitation (AR) is unclear. In this study we aim: (1) to assess the capability of the CircAdapt model of the heart and circulation to simulate hemodynamics in AR; (2) to determine the interaction between aortic compliance and AR using CircAdapt. We simulated three degrees of AR by changing the aortic regurgitant orifice area (ROA) with normal and low aortic compliance. The higher the ROA is, the higher the systolic left ventricular and aortic pressures, the lower the diastolic aortic pressures and the higher the diastolic left ventricular pressures are. For low aortic compliance, those effects are exacerbated, but the regurgitant blood volume is decreased. These simulation data show the capability of CircAdapt to simulate hemodynamics in AR, and suggest that patient-to-patient variability in aortic compliance should be taken into account when assessing AR severity using imaging-based hemodynamic metrics

A web-based tool for cardiac dyssynchrony assessment on ultrasound data

Comunicació presentada al congrés Eurographics Workshop on Visual Computing for Biology and Medicine que va tenir lloc el 7 i 8 de setembre a Bremen, Alemanya.Cardiac resynchronization therapy (CRT) is a broadly used therapy in patients that suffers from heart failure (HF). The positive outcome of CRT depends strongly on the parameters criteria used to select patients and a lot of research has been done to introduce new and more reliable parameters. In this paper we propose an interactive tool to perform visual assessment and measurements on cardiac ultrasound images of patient with cardiac dyssynchrony. The tool is developed as a web application, allowing doctors to remotely access images and measurements.The authors acknowledge the European Union’s Seventh Framework Programme for research, technological development and demonstration (VP2HF FP7-2013-611823 and MEDIA FP7- HEALTH- 2010-261409), the Spanish Ministry of Economy and Competitiveness (TIN2012-35874) and the Maria de Maeztu Units of Excellence Programme (MDM-2015-0502)