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In this study, a self-powered sensor based on polypyrrole modified melamine aerogel (PPy@MA) was developed and evaluated for monitoring constant humidity and flowing moisture. This sensor has a flexible, ultralight and ultraporous structure, and could generate humidity-induced open-circuit voltage from the concentration gradient of the H+ ions. The PPy@MA humidity sensor generated the voltage of 105 mV, when it was placed in an environment with constant humidity of RH 98%. The response and recovery time was 32 s and 13 s, respectively, as the humidity changed between RH 11% and RH 98%. Furthermore, the sensitivity of the self-powered humidity sensor was evaluated by assessing the moisture changes of the human skin, and the moisture from the human breath.

El objetivo de esta tesis fue el de explorar nuevas estrategias nutricionales para combatir patógenos digestivos durante el periodo post-destete de los lechones y así poder contribuir a la reducción del uso de antibióticos. En un primer momento se evaluó in vitro el potencial de algunos macro-ingredientes (trigo, maíz, avena, centeno, harina de soja 44%, haba de soja extrusionada, colza, harina de pescado, lactosuero dulce y salvados de trigo, espelta, kamut, centeno, avena y arroz) para prevenir la adhesión de ETEC K88 a las células epiteliales intestinales (IPEC-J2). En una segunda etapa, se estudió el potencial de los exopolisacáridos (EPS) microbianos obtenidos a partir de la fermentación industrial de la aceituna verde de mesa, para adherir específicamente ETEC K88 y bloquear su adhesión a las células IPEC-J2. Así mismo se analizó la composición química y la estructura de este co-producto y se exploraron nuevas estrategias para mejorar su funcionalidad mediante la evaluación de diferentes cepas de Lactobacillus pentosus y Candida boidinii como inóculos en la fermentación de la aceituna. Se diseñaron tres pruebas. En la primera se demostró que el trigo, maíz, avena, cebada, centeno, harina de soja 44%, haba de soja extrusionada, así como el lactosuero dulce, poseían una clara afinidad para adherir ETEC K88. El centeno, la avena, y también el trigo, fueron también capaces de reducir la adhesión de ETEC K88 a las células IPEC-J2. Todos los salvados de cereales testados demostraron adherir ETEC K88 y todos ellos, salvo el salvado de arroz, reducir la adhesión de ETEC a IPEC-J2. En la segunda prueba, el análisis mediante GLC, reveló como componentes mayoritarios de los EPS la glucosa seguida de la ramnosa y arabinosa. El espectro 1H NMR mostró la presencia de una alfa-piranosa en la forma α-D-Glcp-(1) y dos alfa-furanosas compatibles con α-D-Glcf a i α-D-Galf. Los tests miniaturizados demostraron la capacidad de los EPS de adherir específicamente ETEC K88 y remover, The aim of this Thesis was to explore new feed strategies to fight digestive pathogens in piglets and contribute to reduce the use of antibiotics at weaning. Firstly we explore in vitro the potential of some common macro-ingredients (wheat, corn, oats, barley, rye, soybean meal 44%, extruded full-fat soybean meal, rapeseed, fish meal, sweet whey powder and brans from wheat, spelt, kamut, rye, oat and rice) to prevent the intestinal adhesion of ETEC K88 to intestinal epithelial cells (IPEC-J2). Secondly we also explore the potential of microbial exopolysaccharides (EPS) isolated from the industrial fermentation of table green olives, to attach specifically ETEC K88 and also to block its adhesion to IPEC-J2 cells. The chemical composition and structure of this by-product is also analyzed in this Thesis and new strategies to improve the functionality of these microbial EPSs are explored testing different mates of Lactobacillus pentosus and Candida boidinii strains as starters in the fermentation of olives. In order to achieve these main objectives a set of three trails were designed. First trial showed that wheat, corn, oats, barley, rye, soybean meal 44%, extruded full-fat soybean meal, as well as sweet whey powder, all demonstrated a clear affinity to attach ETEC K88. Regarding rye, oats and also wheat, all of them could also reduce ETEC K88 adhesion to IPEC-J2 cells. Among differently tested cereal brans, all demonstrated an ability to attach ETEC K88 and also all of them, except rice bran, were able to reduce the pathogen attachment to IPEC-J2 cells. In the second trial the chemical composition of EPS is analyzed by GLC revealing that the main components are glucose and galactose followed by rhamnose and arabinose. The 1H NMR spectrum showed the presence of an α-pyranose in the form of α-D-Glcp-(1) and two different α-furanoses attributed to α-D-Glcf and α-D-Galf. Results from miniaturized tests demonstrated the ability of EPS samples to attach specifically to ETEC