treNch: Ultra-Low Power Wireless Communication Protocol for IoT and Energy Harvesting

Although the number of Internet of Things devices increases every year, efforts to decrease hardware energy demands and to improve efficiencies of the energy-harvesting stages have reached an ultra-low power level. However, no current standard of wireless communication protocol (WCP) can fully address those scenarios. Our focus in this paper is to introduce treNch, a novel WCP implementing the cross-layer principle to use the power input for adapting its operation in a dynamic manner that goes from pure best-effort to nearly real time. Together with the energy-management algorithm, it operates with asynchronous transmissions, synchronous and optional receptions, short frame sizes and a light architecture that gives control to the nodes. These features make treNch an optimal option for wireless sensor networks with ultra-low power demands and severe energy fluctuations. We demonstrate through a comparison with different modes of Bluetooth Low Energy (BLE) a decrease of the power consumption in 1 to 2 orders of magnitude for different scenarios at equal quality of service. Moreover, we propose some security optimizations, such as shorter over-the-air counters, to reduce the packet overhead without decreasing the security level. Finally, we discuss other features aside of the energy needs, such as latency, reliability or topology, brought again against BLE.ECSEL Joint Undertaking through CONNECT project 737434Federal Ministry of Education & Research (BMBF)European Union's Horizon 2020 research and innovation programSpanish Ministry of Education, Culture and Sport (MECD)/FEDER-EU FPU18/01376BBVA FoundationUniversity of Granad

Cost-effective printed electrodes based on emerging materials applied to biosignal acquisition

In this paper flexible printed electrodes applicable to wearable electronics are presented. Using innovative materials as Laser Induced Graphene (LIG) and printed electronics, three type of electrodes based in LIG, silver chloride and carbon inks have been compared during the acquisition of bipotentials as electrocardiogram, electromyogram and electrooculogram. For this last one, a completely new framework for acquisition have been developed. This framework is based in a printed patch which integers 6 electrodes for the EOG acquisitions and an ad-hoc signal processing to detect the direction and amplitude of the eye movement. The performance of the developed electrodes have been compared with commercial ones using the characteristics parameters of each signal as comparative variables. The results obtained for the flexible electrodes have shown a similar performance than the commercial electrodes with an improvement in the comfort of the user.Spanish Ministry of Education, Culture and Sport (MECD)/FEDER-EU TEC2017-89955-P FPU16/01451 FPU18/01376BBVA FoundationUniversity of Granad

Non-Intrusive Tank-Filling Sensor Based on Sound Resonance

Different types of fill-level measurement systems exist in the market, but most of them imply some type of intrusion in the tank itself. In this paper, a reconfigurable system based on sound resonance for measuring the fill-level of a tank from the exterior is presented. A relation between sound resonance frequencies and the content of the tank has been found, especially as the tank gets closer to being full. A prototype has been created using reconfigurable technologies combined with wireless communications in order to control the system from an ad hoc application. With this prototype, the fill-level of different tanks has been measured with good resolution, especially when the tank is over half of its capacity

Demonstration of bare Laser reduced Graphene Oxide sensors for Ammonia and Ethanol

This work was mainly supported by TED2021-129949A-I00 funded by MCIN/AEI/10.13039/501100011033. It was also partially funded by the Andalusian regional projects supported through the Junta de Andalucía - Consejería de Universidad, Investigación e Innovación and FEDER funds: ProyExcel_00268, B-RNM-680-UGR20, P20_00265, P20_00633, as well as by the Spanish Ministry of Sciences and Innovation through the National Project PID2020-117344RB-I00, the Ramón y Cajal fellow RYC2019-027457-I and the María Zambrano fellow C21.I4.P1.In this work, gas sensors using laser-reduced graphene oxide (LrGO) as sensitive layer have been fabricated and studied. The laser-synthetized material were structurally and electrically characterized by means of Scanning Electron Microscopy (SEM), Raman spectroscopy, X-ray Photoelectron Spectroscopy (XPS) and the four-point contact method. The gas-sensing properties of the samples were studied by their exposition to 10 ppm to 100 ppm of ethanol and 25 ppm to 130 ppm of ammonia. The results show that the devices present an electrical response corresponding to a purely resistive behavior up to 100 kHz. It is also demonstrated that the resistivity of the sensing layer increases as the gas concentration increases; being of 0.0402 ± 0.001 [%/ppm] for the case of ammonia and 0.0140 ± 0.001 [%/ppm] for the case of ethanol. These results outperform existing sensors and establish a better balance in terms of simplicity, sensitivity, linearity and technology sustainability. In summary, this work especially shows the potential of LrGO for low-cost and low-energy gas sensors fabrication.MCIN/AEI/10.13039/501100011033: TED2021-129949A-I00Junta de AndalucíaFEDER funds: ProyExcel_00268, B-RNM-680-UGR20, P20_00265, P20_00633Spanish Ministry of Sciences and Innovation PID2020-117344RB-I00Ramón y Cajal fellow RYC2019-027457-IMaría Zambrano fellow C21.I4.P

A versatile wearable based on reconfigurable hardware for biomedical measurements

In this work a versatile hardware platform based on reconfigurable devices is presented. This platform it intended for the acquisition of multiple biosignals, only requiring a reconfiguration to switch applications. This prototype has been combined with graphene-based, flexible electrodes to cover the application to different biosignals presented in this paper, which are electrocardiogram, electrooculogram and electromyogram. The features of this system provide to the user and to medical personnel a complete set of diagnosis tools, available both at home and hospitals, to be used as a triage tool and for remote patient monitoring. Additionally, an Android application has been developed for signal processing and data presentation to the user. The results obtained demonstrate the wide range of possibilities in portable/wearable applications of the combination of reconfigurable devices and flexible electronics, especially for the remote monitoring of patients using multiple biosignals of interest. The versatility of this device makes it a complete set of monitoring tools integrated in a reduced size device

Wearable System for Biosignal Acquisition and Monitoring Based on Reconfigurable Technologies

Wearable monitoring devices are now a usual commodity in the market, especially for the monitoring of sports and physical activity. However, specialized wearable devices remain an open field for high-risk professionals, such as military personnel, fire and rescue, law enforcement, etc. In this work, a prototype wearable instrument, based on reconfigurable technologies and capable of monitoring electrocardiogram, oxygen saturation, and motion, is presented. This reconfigurable device allows a wide range of applications in conjunction with mobile devices. As a proof-of-concept, the reconfigurable instrument was been integrated into ad hoc glasses, in order to illustrate the non-invasive monitoring of the user. The performance of the presented prototype was validated against a commercial pulse oximeter, while several alternatives for QRS-complex detection were tested. For this type of scenario, clustering-based classification was found to be a very robust option.This work was funded by Banco Santander and Centro Mixto UGR-MADOC through project SIMMA (code 2/16). The contribution of Víctor Toral was funded by the University of Granada through a grant from the “Iniciación a la investigación 2016” program. The contribution of Antonio García was partially funded by Spain’s Ministerio de Educación, Cultura y Deporte (Programa Estatal de Promoción del Talento y su Empleabilidad en I+D+i, Subprograma Estatal de Movilidad, within Plan Estatal de Investigación Científica y Técnica y de Innovación 2013-2016) under a “Salvador de Madariaga” grant (PRX17/00287). The contribution of Francisco J. Romero was funded by Spain’s Ministerio de Educación, Cultura y Deporte under a FPU grant (FPU16/01451). The contribution of Francisco M. Gómez-Campos was funded by Spain’s Ministerio de Economía, Industria y Competitividad under Project ENE2016_80944_R

Antimicrobial Activity of Biogenic Silver Nanoparticles from Syzygium aromaticum against the Five Most Common Microorganisms in the Oral Cavity

ARTICULO DE ACCESO LIBREAbstract: Syzygium aromaticum (clove) has been used as a dental analgesic, an anesthetic, and a bioreducing and capping agent in the formation of metallic nanoparticles. The main objective of this study was to evaluate the antimicrobial effect in oral microorganisms of biogenic silver nanoparticles (AgNPs) formed with aqueous extract of clove through an ecofriendly method “green synthesis”. The obtained AgNPs were characterized by UV-Vis (ultraviolet-visible spectroscopy), SEM-EDS (scanning electron microscopy–energy dispersive X-ray spectroscopy), TEM (transmission electron microscopy), and ζ potential, while its antimicrobial effect was corroborated against oral Grampositive and Gram-negative microorganisms, as well as yeast that is commonly present in the oral cavity. The AgNPs showed absorption at 400–500 nm in the UV-Vis spectrum, had an average size of 4–16 nm as observed by the high-resolution transmission electron microscopy (HR-TEM), and were of a crystalline nature and quasi-spherical form. The antimicrobial susceptibility test showed inhibition zones of 2–4 mm in diameter. Our results suggest that AgNPs synthesized with clove can be used as effective growth inhibitors in several oral microorganisms.S/

Mechanical Properties and Antibacterial Effect on Mono-Strain of Streptococcus mutans of Orthodontic Cements Reinforced with Chlorhexidine-Modified Nanotubes

Recently, several studies have introduced nanotechnology into the area of dental materials with the aim of improving their properties. The objective of this study is to determine the antibacterial and mechanical properties of type I glass ionomers reinforced with halloysite nanotubes modified with 2% chlorhexidine at concentrations of 5% and 10% relative to the total weight of the powder used to construct each sample. Regarding antibacterial effect, 200 samples were established and distributed into four experimental groups and six control groups (4 +ve and 2 −ve), with 20 samples each. The mechanical properties were evaluated in 270 samples, assessing microhardness (30 samples), compressive strength (120 samples), and setting time (120 samples). The groups were characterized by scanning electron microscopy and Fourier transform infrared spectroscopy, and the antibacterial activity of the ionomers was evaluated on Streptococcus mutans for 24 h. The control and positive control groups showed no antibacterial effect, while the experimental group with 5% concentration showed a zone of growth inhibition between 11.35 mm and 11.45 mm, and the group with 10% concentration showed a zone of growth inhibition between 12.50 mm and 13.20 mm. Statistical differences were observed between the experimental groups with 5% and 10% nanotubes. Regarding the mechanical properties, microhardness, and setting time, no statistical difference was found when compared with control groups, while compressive strength showed higher significant values, with ionomers modified with 10% concentration of nanotubes resulting in better compressive strength values. The incorporation of nanotubes at concentrations of 5% and 10% effectively inhibited the presence of S. mutans, particularly when the dose–response relationship was taken into account, with the advantage of maintaining and improving their mechanical properties

Breve historia de la Facultad de Odontología

La Facultad de Odontología se fundó el 27 de diciembre de 1963 e inició actividades el 3 de marzo de 1964. Años más tarde, el 19 de mayo de 1986, el H. Consejo Universitario aprobó su cambio de escuela a Facultad de Odontología. La conmemoración de 55 años de esta Facultad y 40 años de hermandad con las Universidades de Meikai y Asahi, se constituye un momento oportuno para manifestar el testimonio de cuanto han realizado hombres y mujeres que han dejado huella en esta institución

Ciencia Odontológica 2.0

Libro que muestra avances de la Investigación Odontológica en MéxicoEs para los integrantes de la Red de Investigación en Estomatología (RIE) una enorme alegría presentar el segundo de una serie de 6 libros sobre casos clínicos, revisiones de la literatura e investigaciones. La RIE está integrada por cuerpos académicos de la UAEH, UAEM, UAC y UdeG