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Upper-extremity exoskeletons have demonstrated potential as augmentative, assistive, and rehabilitative devices. Typical control of upper-extremity exoskeletons have relied on switches, force/torque sensors, and surface electromyography (sEMG), but these systems are usually reactionary, and/or rely on entirely hand-tuned parameters. sEMG-based systems may be able to provide anticipatory control, since they interface directly with muscle signals, but typically require expert placement of sensors on muscle bodies. We present an implementation of an adaptive sEMG-based exoskeleton controller that learns a mapping between muscle activation and the desired system state during interaction with a user, generating a personalized sEMG feature classifier to allow for anticipatory control. This system is robust to novice placement of sEMG sensors, as well as subdermal muscle shifts. We validate this method with 18 subjects using a thumb exoskeleton to complete a book-placement task. This learning-from-demonstration system for exoskeleton control allows for very short training times, as well as the potential for improvement in intent recognition over time, and adaptation to physiological changes in the user, such as those due to fatigue., Jeptha H. and Emily V. Wade Fund

[spa] Los resultados obtenidos demuestran que la función y la biogénesis mitocondriales del tejido adiposo blanco dependen del sexo, del depósito y de la dieta ingerida, y que el dimorfismo sexual se manifiesta ya a edades tempranas. Las hormonas ováricas serían responsables, en parte, de este dimorfismo sexual, especialmente en el depósito gonadal, lo que vincula, por tanto, a los estrógenos, al mayor grado de diferenciación mitocondrial y a la expresión de adiponectina. La dieta hiperlipídica atenúa el dimorfismo sexual observado en los animales controles a nivel de la función y la biogénesis mitocondriales y desvincula la relación existente entre la función mitocondrial y la síntesis de adiponectina. Además, induce un mayor incremento del peso corporal y de la adiposidad en las ratas hembra, lo que sugiere una mayor capacidad de expansión de su tejido adiposo. Esto les permite evitar la acumulación de grasa ectópica, manteniendo una mejor sensibilidad a la insulina al evitar los efectos de la lipotoxicidad, [eng] White adipose tissue (WAT) has been considered a simple fat storage depot for a long time, but nowadays it has become recognized as a major endocrine organ in the whole body. Its capacity to synthesize over 50 protein factors known as adipokines, which are able to regulate insulin sensitivity, the inflammatory response or the coagulation process, has led to reconsider its function. Firstly, the mitochondrion has become an important organelle in the adipocyte, playing a relevant role in adipogenesis and in the synthesis of some adipokines, such as adiponectin and, secondly, it is thought that WAT mitochondrial function may be involved in the development of insulin resistance. The main objective of this thesis was based on the study of the influence of sex on alterations in WAT mitochondrial function and biogenesis, both in the control situation and in response to a high-fat diet (HFD). Moreover, the aim was to go further into the relationship between mitochondrial function and obesity-associated insulin resistance development as well as to study the role of sex hormones in the differences found between sexes. The results show that mitochondrial function and biogenesis in WAT depend on the sex, the depot and the diet consumed, and that sexual dimorphism is already present at an early age. Female rats show that the retroperitoneal depot has a more abundant but less differentiated mitochondrial population than males, in contrast to what happens in the periovarian depot, which has more differentiated mitochondria than the epididymal one. Greater mitochondrial differentiation in the periovarian depot leads to the increased adiponectin expression in this depot and higher systemic HMW adiponectin levels (the more active form of this adipokine, with insulin-sensitizing effects) found in female rats. These characteristics lead to a better insulin sensitivity profile in this sex, both at a systemic and tissue level, as female rats show a more activated insulin

[spa] Los resultados obtenidos demuestran que la función y la biogénesis mitocondriales del tejido adiposo blanco dependen del sexo, del depósito y de la dieta ingerida, y que el dimorfismo sexual se manifiesta ya a edades tempranas. Las hormonas ováricas serían responsables, en parte, de este dimorfismo sexual, especialmente en el depósito gonadal, lo que vincula, por tanto, a los estrógenos, al mayor grado de diferenciación mitocondrial y a la expresión de adiponectina. La dieta hiperlipídica atenúa el dimorfismo sexual observado en los animales controles a nivel de la función y la biogénesis mitocondriales y desvincula la relación existente entre la función mitocondrial y la síntesis de adiponectina. Además, induce un mayor incremento del peso corporal y de la adiposidad en las ratas hembra, lo que sugiere una mayor capacidad de expansión de su tejido adiposo. Esto les permite evitar la acumulación de grasa ectópica, manteniendo una mejor sensibilidad a la insulina al evitar los efectos de la lipotoxicidad, [eng] White adipose tissue (WAT) has been considered a simple fat storage depot for a long time, but nowadays it has become recognized as a major endocrine organ in the whole body. Its capacity to synthesize over 50 protein factors known as adipokines, which are able to regulate insulin sensitivity, the inflammatory response or the coagulation process, has led to reconsider its function. Firstly, the mitochondrion has become an important organelle in the adipocyte, playing a relevant role in adipogenesis and in the synthesis of some adipokines, such as adiponectin and, secondly, it is thought that WAT mitochondrial function may be involved in the development of insulin resistance. The main objective of this thesis was based on the study of the influence of sex on alterations in WAT mitochondrial function and biogenesis, both in the control situation and in response to a high-fat diet (HFD). Moreover, the aim was to go further into the relationship between mitochondrial function and obesity-associated insulin resistance development as well as to study the role of sex hormones in the differences found between sexes. The results show that mitochondrial function and biogenesis in WAT depend on the sex, the depot and the diet consumed, and that sexual dimorphism is already present at an early age. Female rats show that the retroperitoneal depot has a more abundant but less differentiated mitochondrial population than males, in contrast to what happens in the periovarian depot, which has more differentiated mitochondria than the epididymal one. Greater mitochondrial differentiation in the periovarian depot leads to the increased adiponectin expression in this depot and higher systemic HMW adiponectin levels (the more active form of this adipokine, with insulin-sensitizing effects) found in female rats. These characteristics lead to a better insulin sensitivity profile in this sex, both at a systemic and tissue level, as female rats show a more activated insulin