Ferroelectric Tunnel Junctions

Ferroelectricity and quantum-mechanical electron tunneling are well-known physical phenomena that have been studied for as long as a century. During this long period, scientific research has been restricted either to ferroelectricity or to electron tunneling. Never before have these subjects been combined into a new phenomenon based on their interaction. Within this work, I present the novel concept of a ferroelectric tunnel junction, where the term ferroelectric refers to a property of the barrier material. This device consists of a ferroelectric layer sandwiched between metal electrodes. The thickness of the ferroelectric layer is thin enough to allow for electron tunneling. For the first time, the influence of macroscopic parameters, such as the spontaneous polarization and strain on quantum-mechanical electron tunneling through a ferroelectric tunnel barrier is studied experimentally. In addition, the experimental work is accompanied by theoretical ideas and predictions concerning the manifestation of piezoelectricity or ferroelectricity in direct electron tunneling

Microvascular cutaneous coverage in wounds that expose the Achilles tendon: case report

Achilles tendon rupture, being one of the main tendon ruptures present, surgery being the most favourable option even taking into account complications such as infections and skin necrosis, it is necessary to develop techniques which help to reduce complications and increase benefits. The methods follow-up of 2 cases of patients with skin defects in the region of the Achilles tendon in patients who were treated at the "Luis Guillermo lbarra lbarra" national rehabilitation institute during the period 2020-2021 in the Traumatology service, treated with radial free flap forearm, using the description of the most used flaps in the literature. Results in both cases integrity of the free radial forearm flap in its entirety, functional recovery for walking, ability to put shoes back on, and without the need for reoperation, as well as a high level of satisfaction by patients. Conclusions if we are talking about an Achilles tendon rupture with a significant skin defect, the free radial forearm flap is an adequate option, if we are talking about a complete defect, the composite flap is the best option, remember that the decision on what type of flap will be used will depend on of the size of the lesion

Segmentación de la válvula pulmonar a partir de imágenes de tomografía cardiaca usando una estrategia basada en realce por similaridad local

En el siguiente artículo se da a conocer el uso de la estrategia similaridad local, en la segmentación tridimensional (3D) de la válvula pulmonar en 20 imágenes cardiacas de tomografía computarizada multicapa, correspondientes al ciclo car- diaco completo de un sujeto. La estrategia consta de las siguientes etapas: a) pre-procesamiento, b) segmentación y c) entonación de parámetros. La etapa a) se aplica, preli- minarmente al instante de diástole nal y se divide en dos fases denominadas: Filtrado y De nición de una región de interés (ROI) y se emplea la técnica denominada realce por similaridad local (LSE). La aplicación de estas fases tiene por nalidad abordar los problemas de ruido, artefactos y bajo contraste que poseen las mencionadas imágenes. La etapa b) permite la segmentación de la válvula pulmo- nar, mediante un algoritmo de agrupamiento denomina- do crecimiento de regiones (RG) el cual es aplicado a las imágenes pre-procesadas. El RG es inicializado con un vó- xel “semilla” el cual es detectado mediante un operador de inteligencia arti cial denominado máquinas de sopor- te vectorial de mínimos cuadrados (LSSVM). Finalmente, durante la etapa c), una métrica denominada coe ciente de Dice (Dc) es utilizada para comparar las segmentacio- nes obtenidas mediante la estrategia propuesta y la seg- mentación generada, manualmente, por un cardiólogo. La combinación de técnicas de ltrado que genera el Dc más elevado considerando el instante de diástole se aplica posteriormente a las 19 imágenes 3D restantes, obtenién- dose un Dc promedio comparable con el reportado en la literatura especializada

Pintando perros: estudio de la anatomía y biomecánica canina a través de la pintura sobre el animal vivo

Creación de un material docente (para web y plataformas móviles) pintando las estructuras anatómicas músculo-esqueléticas sobre perros vivos para el aprendizaje de la Anatomía funcional y Biomecánica canina de forma sencilla, visual y didáctica

Pintando caballos: Estudio de la Anatomía y Biomecánica Equina a través de la Pintura sobre el Animal Vivo

Creación de un material docente (para web y plataformas móviles) pintando las estructuras anatómicas músculo-esqueléticas sobre caballos vivos para el aprendizaje de la anatomía funcional y biomecánica equina de forma sencilla, visual y didáctica

Infectious Diseases, Social, Economic and Political Crises, Anthropogenic Disasters and Beyond: Venezuela 2019 – Implications for Public Health and Travel Medicine

During last months, there have been a significant increase in the evidences showing the catastrophic health situation in Venezuela. There are multiple epidemics, increase in emerging and reemerging infectious, tropical and parasitic diseases as consequences of the social, economic and political crises, which would be considered today a clearly anthropogenic disaster. Venezuela is facing in 2019, the worse sanitary conditions, with multiple implications for public health and travel medicine. So far, from a global perspective, this situation will be an impediment for the achievement of the sustainable development goals (SDG) in 2030. In this multiauthor review, there is a comprehensive analysis of the situation for infectious diseases, non-communicable diseases, their impact in the Americas region, given the migration crisis as well as the comparative status of the SDG 2030. This discussion can provide input for prioritizing emerging health problems and establish a future agenda

Infectious Diseases, Social, Economic and Political Crises, Anthropogenic Disasters and Beyond: Venezuela 2019 – Implications for Public Health and Travel Medicine

During last months, there have been a significant increase in the evidences showing the catastrophic health situation in Venezuela. There are multiple epidemics, increase in emerging and reemerging infectious, tropical and parasitic diseases as consequences of the social, economic and political crises, which would be considered today a clearly anthropogenic disaster. Venezuela is facing in 2019, the worse sanitary conditions, with multiple implications for public health and travel medicine. So far, from a global perspective, this situation will be an impediment for the achievement of the sustainable development goals (SDG) in 2030. In this multiauthor review, there is a comprehensive analysis of the situation for infectious diseases, non-communicable diseases, their impact in the Americas region, given the migration crisis as well as the comparative status of the SDG 2030. This discussion can provide input for prioritizing emerging health problems and establish a future agenda

Combining MRI and clinical data to detect high relapse risk after the first episode of psychosis

Detecting patients at high relapse risk after the first episode of psychosis (HRR-FEP) could help the clinician adjust the preventive treatment. To develop a tool to detect patients at HRR using their baseline clinical and structural MRI, we followed 227 patients with FEP for 18–24 months and applied MRIPredict. We previously optimized the MRI-based machine-learning parameters (combining unmodulated and modulated gray and white matter and using voxel-based ensemble) in two independent datasets. Patients estimated to be at HRR-FEP showed a substantially increased risk of relapse (hazard ratio = 4.58, P < 0.05). Accuracy was poorer when we only used clinical or MRI data. We thus show the potential of combining clinical and MRI data to detect which individuals are more likely to relapse, who may benefit from increased frequency of visits, and which are unlikely, who may be currently receiving unnecessary prophylactic treatments. We also provide an updated version of the MRIPredict software

Competencias básicas para la aplicación de la medicina regenerativa en la clínica de pequeños animales

Depto. de Medicina y Cirugía AnimalFac. de VeterinariaFALSEsubmitte