On the performance of carbon-based screen-printed electrodes for (in)organic hydroperoxides sensing in rainwater

Hydroperoxides play important roles in atmospheric chemical processes since they act as strong oxidants. This paper details with the modification, characterization and performance of different carbon-based screen-printed electrodes to develop a sensor that allows to analyze organic and inorganic hydroperoxides in atmospheric samples. Commercial electrodes made up of graphite, graphene, carbon nanotubes and graphene oxide were electrochemically activated and subsequently modified by layer-by-layer method with a conducting polymer of azure-A and electrodeposited platinum nanoparticles. Characterization of modified electrodes was performed by FE-SEM, XPS, Raman spectroscopy, cyclic voltammetry, and impedance spectroscopy. Even though all modified carbonaceous substrates enabled the development of competitive electrochemical sensors for (in)organic hydroperoxides detection, carbon nanotubes underlying substrate exhibited the best performances in terms of sensitivity, stability, limit of detection and linear range. This amperometric sensor displayed linear responses to hydroperoxides over 0.081–450 μM with detection limits in the range of 24–558 nM and sensitivity values among 0.0628±1.6E-4 and 0.0112±0.71E-4 μA/μM for the different hydroperoxides herein studied. The developed electrochemical sensor was successfully applied to the analysis of (in)organic hydroperoxides in rainwater samples. Measurements in rainwater were performed in a city located in the East of Spain and collected at two different sites (downtown and suburban area) on two different dates (July and November 2020). The presented results demonstrated high sensitivity and selectivity for the detection of hydroperoxides among a plethora of substances naturally present in rainwater.This research was supported by the Spanish Ministry of Science, Innovation and Universities (MICINN, https://www.ciencia.gob.es/) with grants PID2019-106468RB-I00 and PID2019-108136RB-C32, the Junta de Comunidades de Castilla-La Mancha with grant SBPLY/17/180501/000276/2, and the UCLM groups research grants 2020-GRIN-28857 and 2020-GRIN-28771, all of them cofounded with FEDER funds, EU

An initiative to improve oral and written skills of Engineering Students

[EN] In this paper, we describe some activities that have been developed to written and oral skills in students of Degree in Electrical and Electronics Engineering in the School of Industrial Engineering in Toledo. Among these activities, we have designed a workshop, included in welcome activities of the school for first year students and two learning activities included in chemistry module. In the workshop, we explained the key points to consider when an oral or written presentation is prepared. Moreover, we tried to make conscious to our students of the importance of the development of written and oral skills. In addition, we have designed an assessment method for oral skills and other skills like critical thinking in the chemistry module, though an exercise that combines conventional evaluation with peer evaluation. As part of this work, an assessment rubric has been developed to mark oral presentations.Baeza-Romero, MT.; Andrés Abellán, F. (2014). An initiative to improve oral and written skills of Engineering Students. Multidisciplinary Journal for Education, Social and Technological Sciences. 1(1):83-100. doi:http://dx.doi.org/10.4995/muse.2014.2196.SWORD8310011Lu, R., Bo, J J. (2007). A Comparison of Anonymous Versus Identifiable e-Peer Review on College Student Writing Performance and the Extent of Critical Feedback. Journal of Interactive Online Learning, 6(2), 100-115

One-pot electrodeposition of multilayered 3D PtNi/polymer nanocomposite. H2O2 determination in aerosol phase

In this work, 3D-structured nanocomposites were synthesized in one pot by electrochemical deposition of alternating layers of an azo type polymer (polyazure-A) with platinum and nickel nanoparticles. The hybrid PtNi/poly(AzA) film was electrochemically deposited on screen-printed carbon electrodes by layer-by-layer assembly as a function of the number of cyclic voltammograms for electrodeposition of the conducting polymer and the electrode potential applied for electro-reduction of the metal salts. The physicochemical characteristics of the resulting films were studied using electrochemical and microscopic techniques. The 3D molecular nanoarchitecture presents a hollow porous structure dependent on the electrode potential set for the electro-reduction of Pt and Ni nanoparticles. The electrochemical sensor was validated in terms of sensitivity, limit of detection, stability and repeatability, exhibiting a highly sensitive H2O2 detection, with LoD 68.5 nM (S/N = 3) at 0.05 V vs. Ag-SPCE for the electrode modified with 20 cycles for the conducting polymer electrodeposition and −2.0 V for metal ions reduction. The aim of this work also included the outcome of the electrochemical sensor after incorporating the room temperature ionic liquid 1‑butyl‑2,3-dimethylimidazolium tetrafluoroborate within the PtNi/poly(AzA) film, which notably improved the analytical parameters of the system, with LoD 14.5 nM at the same potential. Therefore, as proof of concept, the PtNi/poly(AzA) film-based electrode was explored towards the suitability of an electrochemical sensor for the determination of hydrogen peroxide in aerosol phase. The outstanding features of the PtNi/poly(AzA) film-based electrode modified with the aforementioned ionic liquid allowed for the continuous monitoring of H2O2 in an aerosol stream generated with an ultrasonic diffuser at the low applied potential of 0.05 V. In addition, monitoring H2O2 samples through a series of ON/OFF switches for over 3 h, the sensor provided a fast and reproducible response.Grants PID2019–106468RB-I00 and PID2019–108136RB-C32 funded by MCIN/AEI/10.13039/501100011033 and grant 2022‐GRIN‐34199 funded by the own research plan of the UCLM and co-financed by the European Fund for Regional Development (FEDER). RJP is the beneficiary of a postdoctoral contract associated with the first indicated project from the MCIN/AEI. This research was also partially funded by the Next-Generation EU funding (Zambrano21–10, AGB)

OH yields from the CH3CO+O-2 reaction using an internal standard

Laser flash photolysis of CH3C(O)OH at 248 nm was used to create equal zero time yields of CH3CO and OH. The absolute OH yield from the CH3CO + O2 (+M) reaction was determined by following the OH temporal profile using the zero time OH concentration as an internal standard. The OH yield from CH3CO + O2 (+M) was observed to decrease with increasing pressure with an extrapolated zero pressure yield close to unity (1.1 ± 0.2, quoted uncertainties correspond to 95% confidence limits). The results are in quantitative agreement with those obtained from 248 nm acetone photolysis in the presence of O2

Photolysis of frozen iodate salts as a source of active iodine in the polar environment

Reactive halogens play a key role in the oxidation capacity of the polar troposphere. However, sources and mechanisms, particularly those involving active iodine, are still poorly understood. In this paper, the photolysis of an atmospherically relevant frozen 5 iodate salt has been experimentally studied using infrared (IR) spectroscopy. The samples were generated at low temperatures in the presence of di erent amounts of water. The IR spectra have confirmed that under near-UV/Vis radiation iodate is e ciently photolyzed. The integrated IR absorption coe cient of the iodate anion on the band at 750 cm������1 has been measured to be A = 9.5 10������17 cmmolec������1. Using this value, 10 a lower limit of the integrated absorption cross section of iodate, in an ammonium frozen salt, has been estimated for the first time at wavelengths relevant for tropospheric studies ( = 1.1 10������20 cm2 nmmolec������1 from 300 to 900 nm). According to this, we suggest that the photolysis of iodate in frozen salt can potentially provide a pathway for the release of active iodine to the polar atmosphere

BIM en la universidad

126 páginas.La tecnología BIM (Building Information Modeling, por sus siglas en inglés) es un método innovador para facilitar la comunicación entre los sectores de la arquitectura, ingeniería y construcción, donde se genera intercambio de información de manera eficiente, se crean representaciones digitales (modelosv3d ricos en información) de todas las fases del proceso de construcción y simulan el rendimiento en la vida real, lo que perfecciona el flujo de trabajo, aumenta la productividad y mejora la calidad. En México se realizó un estudio en la industria de la construcción (Bim Forum México, encuesta 2017), que analiza las razones por las que las empresas no utilizan BIM; las que destacan que: las licencias y equipos son muy caros (29%), no se cuenta con personal calificado (23%), los clientes no lo requieren (5%), la industria mexicana no está preparada (4%), no hay capacitación en ello (3%), no hay tiempo para implementarlo (2%), etc. Ante tales razones, los desafíos a los que se enfrenta el sector académico es implementar dentro de sus programas de estudio la enseñanza la tecnología BIM para la formación de nuevas generaciones de profesionales (arquitectos e ingenieros) que cuenten con los conocimientos y habilidades necesarias para responder a los retos que se enfrenta la industria de la construcción. El presente documento se enfoca a estudios realizados por académicos de diversas universidades: Worcester Polytechnic Institute, USA; Universidad Politécnica de Madrid; Universidad Autónoma de Yucatán, México; y Universidad Autónoma Metropolitana, Unidad Azcapotzalco, México. Las investigaciones han sido acerca de la experiencia en la implementación de la tecnología BIM en la práctica y en el proceso de enseñanza aprendizaje

CIBERER : Spanish national network for research on rare diseases: A highly productive collaborative initiative

Altres ajuts: Instituto de Salud Carlos III (ISCIII); Ministerio de Ciencia e Innovación.CIBER (Center for Biomedical Network Research; Centro de Investigación Biomédica En Red) is a public national consortium created in 2006 under the umbrella of the Spanish National Institute of Health Carlos III (ISCIII). This innovative research structure comprises 11 different specific areas dedicated to the main public health priorities in the National Health System. CIBERER, the thematic area of CIBER focused on rare diseases (RDs) currently consists of 75 research groups belonging to universities, research centers, and hospitals of the entire country. CIBERER's mission is to be a center prioritizing and favoring collaboration and cooperation between biomedical and clinical research groups, with special emphasis on the aspects of genetic, molecular, biochemical, and cellular research of RDs. This research is the basis for providing new tools for the diagnosis and therapy of low-prevalence diseases, in line with the International Rare Diseases Research Consortium (IRDiRC) objectives, thus favoring translational research between the scientific environment of the laboratory and the clinical setting of health centers. In this article, we intend to review CIBERER's 15-year journey and summarize the main results obtained in terms of internationalization, scientific production, contributions toward the discovery of new therapies and novel genes associated to diseases, cooperation with patients' associations and many other topics related to RD research

Spatiotemporal Characteristics of the Largest HIV-1 CRF02_AG Outbreak in Spain: Evidence for Onward Transmissions

Background and Aim: The circulating recombinant form 02_AG (CRF02_AG) is the predominant clade among the human immunodeficiency virus type-1 (HIV-1) non-Bs with a prevalence of 5.97% (95% Confidence Interval-CI: 5.41–6.57%) across Spain. Our aim was to estimate the levels of regional clustering for CRF02_AG and the spatiotemporal characteristics of the largest CRF02_AG subepidemic in Spain.Methods: We studied 396 CRF02_AG sequences obtained from HIV-1 diagnosed patients during 2000–2014 from 10 autonomous communities of Spain. Phylogenetic analysis was performed on the 391 CRF02_AG sequences along with all globally sampled CRF02_AG sequences (N = 3,302) as references. Phylodynamic and phylogeographic analysis was performed to the largest CRF02_AG monophyletic cluster by a Bayesian method in BEAST v1.8.0 and by reconstructing ancestral states using the criterion of parsimony in Mesquite v3.4, respectively.Results: The HIV-1 CRF02_AG prevalence differed across Spanish autonomous communities we sampled from (p < 0.001). Phylogenetic analysis revealed that 52.7% of the CRF02_AG sequences formed 56 monophyletic clusters, with a range of 2–79 sequences. The CRF02_AG regional dispersal differed across Spain (p = 0.003), as suggested by monophyletic clustering. For the largest monophyletic cluster (subepidemic) (N = 79), 49.4% of the clustered sequences originated from Madrid, while most sequences (51.9%) had been obtained from men having sex with men (MSM). Molecular clock analysis suggested that the origin (tMRCA) of the CRF02_AG subepidemic was in 2002 (median estimate; 95% Highest Posterior Density-HPD interval: 1999–2004). Additionally, we found significant clustering within the CRF02_AG subepidemic according to the ethnic origin.Conclusion: CRF02_AG has been introduced as a result of multiple introductions in Spain, following regional dispersal in several cases. We showed that CRF02_AG transmissions were mostly due to regional dispersal in Spain. The hot-spot for the largest CRF02_AG regional subepidemic in Spain was in Madrid associated with MSM transmission risk group. The existence of subepidemics suggest that several spillovers occurred from Madrid to other areas. CRF02_AG sequences from Hispanics were clustered in a separate subclade suggesting no linkage between the local and Hispanic subepidemics

Reactividad atmosférica de compuestos heterocíclicos pentagonales. Reacción con el radical nitrato

La Química que se desarrolla en la atmósfera está dominada principalmente por procesos de degradación, tales como la fotolisis y las reacciones de oxidación. En este último caso, tres son las especies que se consideran claves en estos procesos atmosféricos: los radicales nitrato (no3) e hidroxilo (oh) y el ozono. Así, la mayoría de los compuestos orgánicos emitidos a la atmosfera son degradados vía química por reacción diurna con el radical oh o por reacción nocturna con el radical no3. Entre los compuestos que se emiten a la atmosfera, se encuentran los compuestos heterocíclicos pentagonales (de origen principalmente antropogénico). Así, tiofeno, furano y pirrol se han detectado en el aire de algunas ciudades como resultado de las emisiones de procesos tales como la gasificación del carbón, la combustión de carburantes fósiles, etc. Los compuestos heterocíclicos no solo son importantes "per se", sino que también lo son por ser compuestos modelo para otras moléculas de mayor peso molecular difíciles de estudiar en el laboratorio como son los compuestos policiclicos aromáticos (pacs) y las dioxinas. En este sentido, un estudio sistemático de las reacciones del radical nitrato con estos compuestos se ha llevado a cabo en esta tesis. El estudio cinético y de productos de reacción se ha realizado utilizando dos sistemas experimentales diferentes. Por un lado, la determinación de las constantes de velocidad a diferentes temperaturas y el estudio de productos de reacción se llevaron a cabo en un sistema de descarga e tubo de flujo con fluorescencia inducida por laser (L.I.F.) y espectrometría de masas como sistemas de detección. Y por otro lado, se han determinado las constantes de velocidad a temperatura ambiente y los productos de reacción para estas reacciones utilizando un sistema estático con bolsas de teflon como reactor, y cg-ms y cg.fid como sistemas de detección. Se han obtenido valores similares de las constantes de velocidad a temperatura ambiente en ambos sistemas, indicando que estas reacciones no presentan dependencia con la presión. Por tanto, los resultados obtenidos a baja presión son extrapolables a condiciones atmosféricas. Además, tanto los resultados cinéticos como de productos de reacción indican que diferentes mecanismos de reacción operan en estas reacciones dependiendo de la naturaleza del heteroatomo y sustituyentes presentes en el ciclo. En general, para los derivados de tiofeno, so2 y compuestos dicarbonilicos insaturados son los productos principales. En el caso del furano. Se ha detectado un compuesto dicarbonilico insaturado y para thf y tht se han observado como productos de reacción hno3 y dos compuestos orgánicos sulfurados, respectivamente