Efectos del envejecimiento y la restricción calórica en la respuesta a la endotelina-1 y la insulina en el sistema cardiovascular

Tesis doctoral inédita leída en la Universidad Autónoma de Madrid, Facultad de Medicina, Departamento de Fisiología. Fecha de lectura: 4-07-201

Air kerma to H-P(3) conversion coefficients for IEC 61267 RQR X-RAY radiation qualities: application to dose monitoring of the lens of the eye in medical diagnostics

Recent studies highlight the fact that the new eye lens dose limit can be exceeded in interventional radiology procedures and that eye lens monitoring could be required for these workers. The recommended operational quantity for monitoring of eye lens exposure is the personal dose equivalent at 3 mm depth Hp(3) (ICRU 51). However, there are no available conversion coefficients in international standards, while in the literature coefficients have only been calculated for monoenergetic beams and for ISO 4037-1 X-ray qualities. The aim of this article is to provide air kerma to Hp(3) conversion coefficients for a cylindrical phantom made of ICRU-4 elements tissue-equivalent material for RQR radiation qualities (IEC-61267) from 40 to 120 kV and for angles of incidence from 0 to 180°, which are characteristic of medical workplace. Analytic calculations using interpolation techniques and Monte Carlo modelling have been compared.Postprint (author's final draft

Fast fashion y Slow fashion. Análisis comparativo desde un enfoque de Marketing de moda

El tema elegido para mi Trabajo de Fin de Grado es “Fast fashion y Slow fashion. Análisis comparativo desde un enfoque de Marketing de moda” donde se plantea cómo las prácticas éticas y responsables con el medio ambiente han impulsado un nuevo modelo de producción y comercialización del sector de la moda. Asimismo, el marketing de las empresas juega un papel fundamental y, en particular, las redes sociales han cambiado el mundo de la industria textil a través de las influencers. De ahí que se analicen los casos de María Pombo y Rocío Osorno. Por otra parte, desde el punto de vista de la demanda existen muchos perfiles de consumidores, desde los compradores compulsivos, los cuales favorecen las industrias que se rigen por el concepto de Fast fashion, hasta aquellos que están concienciados con la sostenibilidad decantándose por su contrapuesto Slow fashion. El trabajo culmina con una entrevista a un experto en moda dándonos a conocer otro enfoque del Fast fashion y Slow fashion aplicados a la vida real.Grado en Comerci

Clone Swarms: Learning to Predict and Control Multi-Robot Systems by Imitation

In this paper, we propose SwarmNet -- a neural network architecture that can learn to predict and imitate the behavior of an observed swarm of agents in a centralized manner. Tested on artificially generated swarm motion data, the network achieves high levels of prediction accuracy and imitation authenticity. We compare our model to previous approaches for modelling interaction systems and show how modifying components of other models gradually approaches the performance of ours. Finally, we also discuss an extension of SwarmNet that can deal with nondeterministic, noisy, and uncertain environments, as often found in robotics applications

Validation of the MC-GPU Monte Carlo code against the PENELOPE/penEasy code system and benchmarking against experimental conditions for typical radiation qualities and setups in interventional radiology and cardiology

Introduction: Interventional procedures are associated with potentially high radiation doses to the skin. The 2013/59/EURATOM Directive establishes that the equipment used for interventional radiology must have a device or a feature informing the practitioner of relevant parameters for assessing patient dose at the end of the procedure. Monte Carlo codes of radiation transport are considered to be one of the most reliable tools available to assess doses. However, they are usually too time consuming for use in clinical practice. This work presents the validation of the fast Monte Carlo code MC-GPU for application in interventional radiology. Methodologies: MC-GPU calculations were compared against the well-validated Monte Carlo simulation code PENELOPE/penEasy by simulating the organ dose distribution in a voxelized anthropomorphic phantom. In a second phase, the code was compared against thermoluminescent measurements performed on slab phantoms, both in a calibration laboratory and at a hospital. Results: The results obtained from the two simulation codes show very good agreement, differences in the output were within 1%, whereas the calculation time on the MC-GPU was 2500 times shorter. Comparison with measurements is of the order of 10%, within the associated uncertainty. Conclusions: It has been verified that MC-GPU provides good estimates of the dose when compared to PENELOPE program. It is also shown that it presents very good performance when assessing organ doses in very short times, less than one minute, in real clinical set-ups. Future steps would be to simulate complex procedures with several projections.Peer ReviewedObjectius de Desenvolupament Sostenible::3 - Salut i BenestarPostprint (published version

Postnatal overfeeding during lactation induces endothelial dysfunction and cardiac insulin resistance in adult rats

Early overnutrition is associated with cardiometabolic alterations in adulthood, likely attributed to reduced insulin sensitivity due to its crucial role in the cardiovascular system. This study aimed to assess the long-term effects of early overnutrition on the development of cardiovascular insulin resistance. An experimental childhood obesity model was established using male Sprague Dawley rats. Rats were organized into litters of 12 pups/mother (L12-Controls) or 3 pups/mother (L3-Overfed) at birth. After weaning, animals from L12 and L3 were housed three per cage and provided ad libitum access to food for 6 months. L3 rats exhibited elevated body weight, along with increased visceral, subcutaneous, and perivascular fat accumulation. However, heart weight at sacrifice was reduced in L3 rats. Furthermore, L3 rats displayed elevated serum levels of glucose, leptin, adiponectin, total lipids, and triglycerides compared to control rats. In the myocardium, overfed rats showed decreased IL-10 mRNA levels and alterations in contractility and heart rate in response to insulin. Similarly, aortic tissue exhibited modified gene expression of TNFα, iNOS, and IL-6. Additionally, L3 aortas exhibited endothelial dysfunction in response to acetylcholine, although insulin-induced relaxation remained unchanged compared to controls. At the molecular level, L3 rats displayed reduced Akt phosphorylation in response to insulin, both in myocardial and aortic tissues, whereas MAPK phosphorylation was elevated solely in the myocardium. Overfeeding during lactation in rats induces endothelial dysfunction and cardiac insulin resistance in adulthood, potentially contributing to the cardiovascular alterations observed in this experimental mode

Beneficial effects of an aged black garlic extract in the metabolic and vascular alterations induced by a high fat/sucrose diet in male rats

Aged black garlic (ABG) is a functional food with antioxidant and anti-inflammatory properties. Recent studies also report its beneficial metabolic effects in a context of obesity or diabetes, although the mechanisms involved are poorly understood. The aim of this work was to analyze the effects of an ABG extract in the vascular and metabolic alterations induced by a high-fat/sucrose diet in rats. For this purpose, male Sprague–Dawley rats were fed either a standard chow (controls; n = 12) or a high-fat/sucrose diet (HFD; n = 24) for 16 weeks. From week 8 on, half of the HFD rats were treated with a commercial ABG extract concentrated in S-allyl cysteine and melanoidins (ABG10+®; 250 mg/kg daily by gavage; 5 mL/kg). ABG10+®-treated rats showed lower mean caloric intake, body weight, triglycerides, low density lipoprotein cholesterol (LDL-c), insulin and leptin serum concentrations and higher high density lipoprotein cholesterol (HDL-c) and adiponectin serum concentrations than non-treated rats. In the hypothalamus, ABG10+® treatment induced an increase in the gene expression of proopiomelanocortin (POMC) and a decrease in leptin receptor (ObR) mRNA levels. No significant changes were found in visceral adipose tissue except for an overexpression of β3-adrenergic receptor (β3-ADR) in ABG-treated rats. In subcutaneous adipose tissue, ABG10+® treatment decreased adipose weight and downregulated the gene expression of PPAR-γ, LPL, ObR and HSL. In brown adipose tissue, an overexpression of InsR, GLUT-4, UCP-1 and β3-ADR in ABG10+®-treated rats was found, whereas PPAR-γ mRNA levels were significantly decreased. Regarding vascular function, ABG10+® treatment attenuated the obesity-induced vasoconstriction in response to potassium chloride both in presence/absence of perivascular adipose tissue (PVAT). On the contrary, aorta segments from ABG-treated rats showed and improved relaxation in response to acetylcholine only when PVAT was present, with this fact possible being related to the decreased gene expression of proinflammatory cytokines in this tissue. In conclusion, ABG10+® administration partially improves the metabolic and vascular alterations induced by a high-fat/high-sucrose diet in rats through modifications in the gene expression of proteins and neuropeptides involved in inflammation, fat metabolism and food intake regulation. Further studies are required to assess the bioavailability of ABG between rats and humans.This study has been funded by Pharmactive Biotech Products S.L

Responsabilidad social corporativa (RSC) y rentabilidad financiera (RF) en el sector turístico

La Responsabilidad Social Corporativa (RSC) se plantea como un elemento estratégico clave en la gestión empresarial. Sin embargo, son escasos los estudios en el sector turístico y además, no son concluyentes con respecto a su relación con la rentabilidad (Miras et al., 2010; Fernández y Cuadrado, 2011). El objeto del presente trabajo es analizar la relación existente entre la aplicación efectiva de los principios de RSC y la Rentabilidad Financiera de las empresas del Sector Turístico. Para el análisis empírico, hemos seleccionado las cadenas hoteleras españolas con mayor reconocimiento reputacional en materia de RSC. Las variables utilizadas en el análisis referidas a los ejercicios 2010 y 2011 son, del lado de la RSC, los ítems de una encuesta cumplimentada por las cadenas hoteleras sobre RSC, efectuada en una tesis previa (Jiménez, 2012); además de algunas variables de control externo procedentes del Global Reporting Initiative y, por otro lado, indicadores de rentabilidad, ROA y ROE, así como el nivel de riesgo de la empresa. Mediante estadística descriptiva, análisis de correlación y análisis gráfico basado en diagramas de dispersión, se muestra en qué medida están correlacionadas la RSC y la Rentabilidad Financiera.Although Corporate Social Responsibility (CSR) is seen as a key strategic element in business management, there is a scarcity of research in the tourism sector and there are still no conclusive studies regarding its relationship with profitability (Miras et al., 2010; Fernández y Cuadrado, 2011). The aim of this study is to analyze the connection between the effective application of the principles of CSR and the financial performance in the Spanish tourism sector. Those Spanish hotel companies owning the highest CSR rates, have been selected for the empirical research. The variables used for this analysis to years 2010 and 2011 are firstly extracted from a survey filled in by the hotel companies about the CSR, which is certified by a dissertation (Jiménez, 2012); and secondly variables obtained by external regulations as the GRI (Global Reporting Initiative). On the other hand, indicators of profitability, ROA, ROE and the business risk level. Descriptive statistics and both a correlation analysis and a graphic analysis based on scatter plots have been developed to explain the actual link between the CSR and the financial performance related to the hotel companies on study

Overfeeding during lactation in rats is associated with cardiovascular insulin resistance in the short-term

Childhood obesity is associated with metabolic and cardiovascular comorbidities. The development of these alterations may have its origin in early life stages such as the lactation period through metabolic programming. Insulin resistance is a common complication in obese patients and may be responsible for the cardiovascular alterations associated with this condition. This study analyzed the development of cardiovascular insulin resistance in a rat model of childhood overweight induced by overfeeding during the lactation period. On birth day, litters were divided into twelve (L12) or three pups per mother (L3). Overfed rats showed a lower increase in myocardial contractility in response to insulin perfusion and a reduced insulin-induced vasodilation, suggesting a state of cardiovascular insulin resistance. Vascular insulin resistance was due to decreased activation of phosphoinositide 3-kinase (PI3K)/Akt pathway, whereas cardiac insulin resistance was associated with mitogen-activated protein kinase (MAPK) hyperactivity. Early overfeeding was also associated with a proinflammatory and pro-oxidant state; endothelial dysfunction; decreased release of nitrites and nitrates; and decreased gene expression of insulin receptor (IR), glucose transporter-4 (GLUT-4), and endothelial nitric oxide synthase (eNOS) in response to insulin. In conclusion, overweight induced by lactational overnutrition in rat pups is associated with cardiovascular insulin resistance that could be related to the cardiovascular alterations associated with this conditionThis study has been funded by the grant to Precompetitive Projects of Universidad San Pablo CEU and Banco Santander 2016, and by a grant from the Community of Madrid (CAM) awarded to Daniel González-Hedström (IND2017/BIO7701, Spain