5 research outputs found
A thorough investigation of the switching dynamics of TiN/Ti/10 nm-HfO2/W resistive memories
The switching dynamics of TiN/Ti/HfO2/W-based resistive memories is investigated. The analysis consisted in
the systematic application of voltage sweeps with different ramp rates and temperatures. The obtained results
give clear insight into the role played by transient and thermal effects on the device operation. Both kinetic
Monte Carlo simulations and a compact modeling approach based on the Dynamic Memdiode Model are
considered in this work with the aim of assessing, in terms of their respective scopes, the nature of the physical
processes that characterize the formation and rupture of the filamentary conducting channel spanning the oxide
film. As a result of this study, a better understanding of the different facets of the resistive switching dynamics is
achieved. It is shown that the temperature and, mainly, the applied electric field, control the switching mechanism
of our devices. The Dynamic Memdiode Model, being a behavioral analytic approach, is shown to be
particularly suitable for reproducing the conduction characteristics of our devices using a single set of parameters
for the different operation regimesFEDER program [PID2022-139586NB-C41, PID2022-
139586NB-C42PID2022-139586NB-C43PID2022-139586NB-C44]The Consejería de Conocimiento, Investigaci´on y UniversidadJunta de
Andalucía (Spain) [B-TIC-624-UGR20]Spanish Consejo Superior
de Investigaciones Científicas (CSIC) [20225AT012]FEDER fundsRamón y Cajal grant number
RYC2020-030150-IEuropean project MEMQuD, code 20FUN06EMPIR programme co-financed by the Participating StatesEuropean Union’s Horizon 2020 research and innovation
programm
TiN/Ti/HfO2/TiN memristive devices for neuromorphic computing: from synaptic plasticity to stochastic resonance
The Supplementary Material for this article can be found
online at: https://www.frontiersin.org/articles/10.3389/fnins.2023.
1271956/full#supplementary-materialFunding
The author(s) declare that financial support was received for
the research, authorship, and/or publication of this article. The
authors thank the support of the Consejeria de Conocimiento,
Investigacion y Universidad, Junta de Andalucia (Spain), and
the FEDER program through project B-TIC-624-UGR20. They
also thank the support of the Federal Ministry of Education and
Research of Germany under Grant 16ME0092.We characterize TiN/Ti/HfO2/TiN memristive devices for neuromorphic
computing. We analyze different features that allow the devices to mimic
biological synapses and present the models to reproduce analytically some of
the data measured. In particular, we have measured the spike timing dependent
plasticity behavior in our devices and later on we have modeled it. The spike timing
dependent plasticity model was implemented as the learning rule of a spiking
neural network that was trained to recognize the MNIST dataset. Variability is
implemented and its influence on the network recognition accuracy is considered
accounting for the number of neurons in the network and the number of training
epochs. Finally, stochastic resonance is studied as another synaptic feature. It is
shown that this effect is important and greatly depends on the noise statistical
characteristics.Consejería de Conocimiento, Investigación y Universidad, Junta de Andalucía (Spain), and the FEDER program through project B-TIC-624-UGR20Federal Ministry of Education and Research of Germany under Grant 16ME009
3D simulation of conductive nanofilaments in multilayer h-BN memristors via a circuit breaker approach
Project PID2022-139586NB-44 funded by
MCIN/AEI/10.13039/501100011033European Union
NextGenerationEU/PRTRProject PP2022.PP-13 funded by
“Ayudas del Plan Propio UGR 2022”King Abdullah University of Science and Technolog
Quorum sensing network in clinical strains of A. baumannii : AidA is a new quorum quenching enzyme
Acinetobacter baumannii is an important pathogen that causes nosocomial infections generally associated with high mortality and morbidity in Intensive Care Units (ICUs). Currently, little is known about the Quorum Sensing (QS)/Quorum Quenching (QQ) systems of this pathogen. We analyzed these mechanisms in seven clinical isolates of A. baumannii. Microarray analysis of one of these clinical isolates, Ab1 (A. baumannii ST-2-clon-2010), previously cultured in the presence of 3-oxo-C12-HSL (a QS signalling molecule) revealed a putative QQ enzyme (α/β hydrolase gene, AidA). This QQ enzyme was present in all nonmotile clinical isolates (67% of which were isolated from the respiratory tract) cultured in nutrient depleted LB medium. Interestingly, this gene was not located in the genome of the only motile clinical strain growing in this medium (A. baumannii strain Ab421-GEIH-2010 [Ab7], isolated from a blood sample). The AidA protein expressed in E. coli showed QQ activity. Finally, we observed downregulation of the AidA protein (QQ system attenuation) in the presence of HO (ROS stress). In conclusion, most of the A. baumannii clinical strains were not surface motile (84%) and were of respiratory origin (67%). Only the pilT gene was involved in surface motility and related to the QS system. Finally, a new QQ enzyme (α/β hydrolase gene, AidA protein) was detected in these strains
Guía de Terapéutica Antimicrobiana del Área Aljarafe, 3ª edición
Coordinadora: Rocío Fernández Urrusuno. Co-coordinadora: Carmen Serrano Martino.YesEstas guías son un recurso indispensable en los Programas de Optimización de Antibióticos (PROA). No sólo constituyen una herramienta de ayuda para la toma de decisiones en los principales síndromes infecciosos, proporcionando recomendaciones para el abordaje empírico de dichos procesos, sino que son el patrón/estándar de referencia que permitirá determinar la calidad o adecuación de los tratamientos realizados. Las guías pueden ser utilizadas, además, como herramienta de base para la formación y actualización en antibioterapia, ya que permiten mantener actualizados los conocimientos sobre las nuevas evidencias en el abordaje de las infecciones. Por último, deberían incorporar herramientas que faciliten el proceso de toma de decisiones compartidas con el paciente.
El objetivo de esta guía es proporcionar recomendaciones para el abordaje de las enfermedades infecciosas más prevalentes en la comunidad, basadas en las últimas evidencias disponibles y los datos de resistencias de los principales patógenos que contribuyan a mejorar la calidad de la prescripción de antimicrobianos