Sensor electroquímic de clor per a aigües potables

El lleixiu, amb el clor que conté, és necessari per a desinfectar l'aigua que prenem, però en dosis elevades podria intoxicar-nos. Per això, és important que les eines que detecten la quantitat de clor en l'aigua siguin fiables. Investigadors del Centre Nacional de Microelectrónica han creat un xip que permet verificar amb exactitud i de manera continuada la quantitat de clor en l'aigua

Antimony tin oxide (ATO) screen-printed electrodes and their application to spectroelectrochemistry

Spectroelectrochemistry studies spectral changes as a function of applied potential or current. While there is no standard experimental setup, transparent electrodes are most typically used in transmission mode. Working in reflection mode forces light across the sample twice, resulting in higher sensitivities, but in turn requires the use of highly reflective electrodes. Here we present the production and characterization of screen-printed electrodes made from different antimony tin oxide (ATO) conducting particles. The resulting electrodes display excellent spectroelectrochemical properties, such as reflectivities up to 20 times higher than conventional graphite screen-printed electrodes, but with comparable electron transfer rates. These electrodes represent an attractive alternative to conventional materials and widen the choice of suitable electrode materials for electrochemistry in general and spectroelectrochemistry in particularFEDER funds managed by the Catalan Secretary of Universities and Research through project PROD-0000114 (Enterprise and Knowledge, Industry Department, Generalitat de Catalunya)

Smartphone-Enabled Personalized Diagnostics: Current Status and Future Prospects

Biosensors; Mètodes moleculars; Diagnòstics basat en telèfons intel·ligentsBiosensores; Métodos moleculares; Diagnósticos basados en teléfonos inteligentesBiosensors; Molecular methods; Smarthphone-based diagnosticsSmartphones are becoming increasingly versatile thanks to the wide variety of sensor and actuator systems packed in them. Mobile devices today go well beyond their original purpose as communication devices, and this enables important new applications, ranging from augmented reality to the Internet of Things. Personalized diagnostics is one of the areas where mobile devices can have the greatest impact. Hitherto, the camera and communication abilities of these devices have been barely exploited for point of care (POC) purposes. This short review covers the recent evolution of mobile devices in the area of POC diagnostics and puts forward some ideas that may facilitate the development of more advanced applications and devices in the area of personalized diagnostics. With this purpose, the potential exploitation of wireless power and actuation of sensors and biosensors using near field communication (NFC), the use of the screen as a light source for actuation and spectroscopic analysis, using the haptic module to enhance mass transport in micro volumes, and the use of magnetic sensors are discussed.Financial support from the Basque Government under the ELKARTEK program is also acknowledged. EB is funded by Instituto de Salud Carlos III, cofinanced by the European Regional Development Fund (grant CPII18/00025)

A self-powered skin-patch electrochromic biosensor

One of the limitations of many skin-patch wearable sensors today is their dependence on silicon-based electronics, increasing their complexity and unit cost. Self-powered sensors, in combination with electrochromic materials, allow simplifying the construction of these devices, leading to powerful analytical tools that remove the need for external detection systems. This work describes the construction, by screen-printing, of a self-powered electrochromic device that can be adapted for the determination of metabolites in sweat by the naked eye in the form of a 3 × 15 mm colour bar. The device comprises a lactate oxidase and osmium-polymer -based anode connected to a coplanar 3 × 15 mm Prussian Blue, PB, cathode printed over a transparent poly(3,4-ethylenedioxythiophene) polystyrene sulfonate, PEDOT:PSS electrode. An ion-gel composed of Poly(vinylidene fluoride-co-hexafluoropropylene), PVDF-co-HFP, a gelling agent, and ionic liquid 1-Ethyl-3-methylimidazolium trifluoromethanesulfonate, EMIM-Tf, effectively separates the cathode display from the biosensing anode, protecting it from the sample. Despite its cathodic electrochromism, the PEDOT:PSS has a transmission above 90% and does not mask the Prussian Blue colour change because the cathode does not operate below 0 V vs Ag/AgCl at any time. The sensor displays lactate concentrations in the range of 0-10 mM over the length of the electrochromic display, which has a contrast ratio of 1.43. Although full response takes up to 24 min, 85% of the colour change is displayed within 10 min

Electrochemical POC device for fast malaria quantitative diagnosis in whole blood by using magnetic beads, Poly-HRP and microfluidic paper electrodes

© 2019 Elsevier B.V. Malaria, a parasitic infection caused by Plasmodium parasites and transmitted through the bite of infected female Anopheles mosquitos, is one of the main causes of mortality in many developing countries. Over 200 million new infections and nearly half a million deaths are reported each year, and more than three billion people are at risk of acquiring malaria worldwide. Nevertheless, most malaria cases could be cured if detected early. Malaria eradication is a top priority of the World Health Organisation. However, achieving this goal will require mass population screening and treatment, which will be hard to accomplish with current diagnostic tools. We report an electrochemical point-of-care device for the fast, simple and quantitative detection of Plasmodium falciparum lactate dehydrogenase (PfLDH) in whole blood samples. Sample analysis includes 5-min lysis to release intracellular parasites, and stirring for 5 more min with immuno-modified magnetic beads (MB) along with an immuno-modified signal amplifier. The rest of the magneto-immunoassay, including sample filtration, MB washing and electrochemical detection, is performed at a disposable paper electrode microfluidic device. The sensor provides PfLDH quantitation down to 2.47 ng mL−1 in spiked samples and for 0.006–1.5% parasitemias in Plasmodium-infected cultured red blood cells, and discrimination between healthy individuals and malaria patients presenting parasitemias >0.3%. Quantitative malaria diagnosis is attained with little user intervention, which is not achieved by other diagnostic methods

A fast synthesis route of boron-carbon-nitrogen ultrathin layers towards highly mixed ternary B-C-N phases

We report a direct and fast synthesis route to grow boron-carbon-nitrogen layers based on microwave-assisted plasma enhanced chemical vapour deposition (PECVD) by using methylamine borane as a single source molecular precursor. This easy and inexpensive method allows controlled and reproducible growth of B-C-N layers onto thin Cu foils. Their morphological, structural, chemical, optical and transport properties have been thoroughly characterized by a number of different microscopies, transport and spectroscopic techniques. Though disorder and segregation into C-rich and h-BN-rich domains have been observed in ultrathin flat few layers, high doping levels have been reached, inducing strong modifications of the electronic, optical and transport properties of C-rich and h-BN-rich phases. This synthesis procedure can open new routes towards the achievement of homogeneous highly mixed ternary B-C-N phase

Elaboración de casos prácticos de Estadística utilizando el software R en el entorno Moodle

Depto. de Estadística e Investigación OperativaFac. de Ciencias MatemáticasFALSEsubmitte

SilvAdapt.Net: A Site-Based Network of Adaptive Forest Management Related to Climate Change in Spain

[EN] Adaptive forest management (AFM) is an urgent need because of the uncertainty regarding how changes in the climate will affect the structure, composition and function of forests during the next decades. Current research initiatives for the long-term monitoring of impacts of silviculture are scattered and not integrated into research networks, with the consequent losses of opportunities and capacity for action. To increase the scientific and practical impacts of these experiences, it is necessary to establish logical frameworks that harmonize the information and help us to define the most appropriate treatments. In this context, a number of research groups in Spain have produced research achievements and know-how during the last decades that can allow for the improvement in AFM. These groups address the issue of AFM from different fields, such as ecophysiology, ecohydrology and forest ecology, thus resulting in valuable but dispersed expertise. The main objective of this work is to introduce a comprehensive strategy aimed to study the implementation of AFM in Spain. As a first step, a network of 34 experimental sites managed by 14 different research groups is proposed and justified. As a second step, the most important AFM impacts on Mediterranean pines, as one of the most extended natural and planted forest types in Spain, are presented. Finally, open questions dealing with key aspects when attempting to implement an AFM framework are discussed. This study is expected to contribute to better outlining the procedures and steps needed to implement regional frameworks for AFM.A.J. Molina is beneficiary of an "APOSTD" fellowship (APOSTD/2019/111) funded by the Generalitat Valenciana. M. Moreno-de las Heras is beneficiary of a Serra Hunter fellowship (UB-LE-9055) funded by the Generalitat de Catalunya. F.J. Ruiz-Gomez is supported by a postdoctoral fellowship of the Junta de Andalucia (Sevilla, Spain), and the European Social Fund 2014-2020 Program (DOC_0055). The authors received national and international funding through the following projects: SILVADAPT.NET (RED2018-102719-T), ESPECTRAMED (CGL2017-86161-R), Life-FOREST CO2 (LIFE14 CCM/ES/001271), ALTERACLIM (CGL2015-69773-C2-1-P), INERTIA (PID2019-111332RB-C22-BDV), CEHYRFO-MED (CGL2017-86839-C3-2-R), DEHESACLIM (IB16185), RESILIENTFORESTS (LIFE17 CCA/ES/000063), Rhysotto (PID2019-106583RB-I00), AGL2017-83828C2-2-R, RTI2018-096884-B-C31, ESPAS (CGL2015-65569-R), and caRRRascal (RTI2018-095037-B-I00).Molina Herrera, A.; Navarro Cerrillo, R.; Pérez-Romero, J.; Alejano, R.; Bellot, JF.; Blanco, JA.; Camarero, JJ.... (2021). SilvAdapt.Net: A Site-Based Network of Adaptive Forest Management Related to Climate Change in Spain. Forests. 12(12):1-27. https://doi.org/10.3390/f12121807127121

Variability and host density independence in inductions-based estimates of environmental lysogeny.

Temperate bacterial viruses (phages) may enter a symbiosis with their host cell, forming a unit called a lysogen. Infection and viral replication are disassociated in lysogens until an induction event such as DNA damage occurs, triggering viral-mediated lysis. The lysogen-lytic viral reproduction switch is central to viral ecology, with diverse ecosystem impacts. It has been argued that lysogeny is favoured in phages at low host densities. This paradigm is based on the fraction of chemically inducible cells (FCIC) lysogeny proxy determined using DNA-damaging mitomycin C inductions. Contrary to the established paradigm, a survey of 39 inductions publications found FCIC to be highly variable and pervasively insensitive to bacterial host density at global, within-environment and within-study levels. Attempts to determine the source(s) of variability highlighted the inherent complications in using the FCIC proxy in mixed communities, including dissociation between rates of lysogeny and FCIC values. Ultimately, FCIC studies do not provide robust measures of lysogeny or consistent evidence of either positive or negative host density dependence to the lytic-lysogenic switch. Other metrics are therefore needed to understand the drivers of the lytic-lysogenic decision in viral communities and to test models of the host density-dependent viral lytic-lysogenic switch