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Selección de aptámeros anti-HER2 y su evaluación en líneas celulares de cáncer de mama
No full textEl cáncer de mama, es el cáncer más común y la principal causa de muerte en mujeres en todo el mundo. Es una enfermedad heterogénea clasificada en distintos subtipos moleculares debido a la presencia o ausencia de receptor de estrógeno (ER), progesterona (PR) o factor de crecimiento epidérmico humano (HER2). El subtipo HER2, comprende casi entre 10-15% de todos los cánceres de mama invasivos. La primera línea de tratamiento del cáncer de mama HER2+, es mediante el uso de anticuerpos Trastuzumab y Pertuzumab, dado que se unen al subdominio IV y II del receptor, respectivamente. En este sentido, las tasas de supervivencia superan el 90% en cáncer de mama HER2+ temprano, si se trata con quimioterapia, terapia con doble anticuerpo, etc. Sin embargo, pacientes con cáncer de mama HER2+ metastásico, desarrollan resistencia a los mismos, lo que conduce a la progresión de la enfermedad, muriendo una gran cantidad de pacientes. Este hecho exige nuevos enfoques terapéuticos para tratar el cáncer, siendo los aptámeros candidatos con gran potencial dada su alta afinidad y alta especificidad por su blanco molecular. Además, tienen rápida penetración en los tejidos, facilidad de ser sintetizados y modificados químicamente, por lo que la administración de fármacos dirigida a tumores, mediante el uso de aptámeros, puede aumentar la eficacia de la terapia y reducir la toxicidad de la misma. Los aptámeros son obtenidos mediante SELEX, realizando distintas rondas contra un blanco específico y posteriormente, realizando la separación y la amplificación de los aptámeros unidos al blanco. De este modo, los aptámeros pueden unirse a blancos específicos, bajo ciertas condiciones (pH, Temperatura, fuerza iónica, etc) formando estructuras definidas, confiriéndoles la capacidad de unirse a diversas moléculas, presentando una unión específica aptámero-ligando con afinidades en el entorno de μM-nM. A efectos de mejorar la estrategia de SELEX, se diseñaron diferentes tipos de metodologías (Cell-SELEX, In Vivo-SELEX, etc) siendo aplicadas de acuerdo a las propiedades y entorno que presente la molécula blanco.
En este marco, se realizó una estrategia de selección de aptámeros por Cell-SELEX, con las líneas celulares BT-474 con alta expresión del receptor HER2. Se realizaron rondas que consistían en un Cell-SELEX convencional y rondas especializadas en las que se utilizó como guía los anticuerpos Trastuzumab y Pertuzumab a efectos obtener aptámeros contra los subdominios II y IV del receptor HER2. Finalmente, el enriquecimiento de las rondas se analizó mediante citometría de flujo. Los resultados indican que se obtuvo una población de aptámeros enriquecidos, lo cual tiene gran potencial para ser utilizado a futuro en aplicaciones biomédicas. Esto nos impulsa a seguir trabajando con los aptámeros generados y en profundizar la caracterización de los mismos
A fair and dynamic load-balancing mechanism
No full textPresentado y publicado en Traffic Management and Traffic Engineering for the Future Internet. FITraMEn 2008The current data network scenario makes Traffic Engineering (TE) a very challenging task. The ever growing access rates and new applications running on end-hosts result in more variable and unpredictable traffic patterns. By providing origin-destination (OD) pairs with several possible paths, load-balancing has proven itself an excellent tool to face this uncertainty. Most previous proposals defined the load-balancing problem as minimizing a certain network cost function of the link’s usage, assuming users would obtain a good performance as a consequence. Since the network operator is interested in the communication between the OD nodes, we propose instead to state the load-balancing problem in their terms. We define a certain utility function of the OD’s perceived performance and maximize the sum over all OD pairs. The solution to the resulting optimization problem can be obtained by a distributed algorithm, whose design we outline. By means of extensive simulations with real networks and traffic matrices, we show that our approach results in more available bandwidth for OD pairs and a similar or decreased maximum link utilization than previously proposed load-balancing schemes. Packet-level simulations verify the algorithm’s good performance in the presence of delayed and inexact measurements.Larroca, F., Rougier, JL. "A fair and dynamic load-balancing mechanism". Publicado en: Valadas, R., Salvador, P. (eds) Traffic Management and Traffic Engineering for the Future Internet. FITraMEn 2008. Lecture Notes in Computer Science, vol 5464. Springer, Berlin, Heidelberg. https://doi.org/10.1007/978-3-642-04576-9_3
Perspectives of TFETs for low power analog Ics
No full textTrabajo presentado al IEEE Subthreshold Microelectronics Conference (SubVT), 2012In this paper we show that tunnel field effect transistors (TFETs) biased in the subthreshold region promise several advantages for low-power/high-frequency analog IC applications (e.g. GHz operation with sub-0.1 mW power consumption). Analytical and TCAD models for graphene nano-ribbon (GNR) and InAs/GaSb nanowire TFETs are employed, respectively, for the first time in subthreshold analog circuit examples using the g m /I d integrated circuit (IC) design technique. From comparison of these TFET technologies with traditional FETs it is observed that due to the higher currents per unit gate width at low voltage for TFETs, smaller, higher speed, and lower power analog circuits are enabled
Special Issue : highlights from the IEEE Latin American Symposium on Circuits and Systems (LASCAS) 2015
No full textPresentación a los lectores del Springer Journal on Analog Integrated Circuits and Signal Processing (ALOG) una selección de artículos ampliados de la 6ª edición del Simposio IEEE Latinoamérica sobre Circuitos y Sistemas (LASCAS 2015)
Software defined radio : from theory to real world communications
No full text13th Technologies Applied to Electronics Teaching Conference (TAEE), La Laguna, Spain, 2018Bridging the gap from theory to real-world, hands- on experience is an always present challenge in Education. The advent of computers allowed for simulation, a halfway step from theory into practice. In Telecommunications Engineering, Software Defined Radio allows students to design and test wireless equipment in real communication by means of a personal computer connected to a simple, low cost, generic radiofrequency device. The paradigm has changed the approach to wireless equipment and communications protocols design across industry and academia. In Education, it has succeeded in providing students with an experience very similar, if not equal, to what they will face in their professional lives. This approach resulted in a deeper understanding and better ability development than was possible through simulation, since several communication problems (such as those related to radiofrequency propagation) are very difficult to model realistically. Moreover, this approach has proved to be strongly motivating for students, who design systems through a graphical interface by interconnecting blocks with specific functionality, but can later experience the results in real communications. This article describes our teaching experience and lessons learned with Software Defined Radio for Engineering Education. We used GNU Radio, an open and free software framework, complemented with GNU Wireless Network, an extension of our design to support data communications. The paradigm involved both graduate and undergraduate courses in Wireless Communication with strong lab content, undergraduate projects, early research training, and several master thesis
A novel framework from Nontechinical Losses Detection in Electricity Companies
No full textPresentado en International Conference, ICPRAM 2012 Vilamoura, Algarve, Portugal, February 6-8, 2012.Nontechnical losses represent a very high cost to power supply companies, who aims to improve fraud detection in order to reduce this losses. The great number of clients and the diversity of different types of fraud makes this a very complex task. In this paper we present a combined strategy based on measures and methods adequate to deal with class imbalance problems. We also describe the features proposed, the selection process and results. Analysis over consumers historical kWh load profile data from Uruguayan Electricity Utility (UTE) shows that using combination and balancing techniques improves automatic detection performance
Design and analysis of flow aware load balancing mechanisms for multi-service networks
No full textEthernet technology is being deployed in metro and wide area networks. However, despite recent evolutions, Ethernet cannot be considered a carrier class technology due mainly to the lack of facilities for efficient traffic engineering (TE). In this article, we propose a Flow-aware TE approach for carrier class Ethernet networks providing services like those defined by the Metro Ethernet Forum. The flow-aware networking approach we consider is based on the Cross-protect router mechanisms, allowing satisfactory quality for streaming and elastic flows without explicitly identifying traffic classes by the combined use of fair queuing and admission control. Our proposal applies specifically to architectures where a tunnel is established between ingress and egress nodes (like Ethernet over MPLS). In this specific context, the Cross-protect mechanisms are applied on a per tunnel basis. We analyze the proposed approach in terms of flow blocking probabilities for which explicit formula are derived. We also extend the study framework to the case where several paths are established between a pair of ingress/egress nodes, and propose a simple load balancing scheme. We analyze its performance and derive approximate formula for the flow blocking probability in this case. The analysis is validated by extensive simulations
Smartphone light sensors as an innovative tool for solar irradiance measurements.
No full textIn recent years, the teaching of experimental science and engineering has been revolutionized by the integration of smartphone sensors, which are widely used by a large portion of the population. Concurrently, interest in solar energy has surged. This raises the important question of how smartphone sensors can be harnessed to incorporate solar energy studies into undergraduate education. We provide comprehensive guidelines for using smartphone sensors in various conditions, along with detailed instructions on how to calibrate them with widely accessible clear-sky satellite data. This smartphone-based method is also compared with professional reference measurements to ensure consistency. This experiment can be easily conducted with most smartphones, basic materials, and a clear, open location over a few hours (methods). The findings demonstrate that smartphones, combined with simple resources, can accurately measure solar irradiance and support experiments on solar radiation physics, atmospheric interactions, and variations in solar energy across locations, cloud cover, and time scales. This approach provides a practical and accessible tool for studying solar energy, offering an innovative and engaging method for measuring solar resources
Acuerdo Marco de Cooperación Internacional entre la Universidad de la República y Université Lumiér Lyon 2
No full textEl objeto del presente Convenio consiste en la cooperación en todos los ámbitos de la educación, la formación y la investigación considerados de interés común. El objetivo es el intercambio de profesores y profesores -investigadores, intercambio de estudiantes, dirección conjunta de tesis y programas educativos o de investigació
Convenio Marco de colaboración entre la Fundación Blanquerna y la Universidad de la República. Facultad de Psicología
No full textEl objeto del presente convenio marco de colaboración consiste en la conjunción de esfuerzos de manera de aprovechar y potenciar sus recursos docentes, metodológicos, técnicos y de ejercicio para el desarrollo de actividades y estudio sobre problemas y asuntos de interés común acerca de los temas de memoria y comunicación