130 research outputs found

    Exploring the Chemistry of Lanthanoid β–Triketonate Complexes

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    This thesis reports the design, synthesis and characterisation of new β-triketonate based lanthanoid complexes. The use of systematically modified β-triketone molecules as ligands for these f-metal ions and their effect on the structural and photophysical properties of the complexes were investigated in detail. This study allowed a better understanding of the relationship between structure and photophysical activity of the lanthanoid complexes and the isolation of unusually efficient near-infrared emitters

    Accessing Lanthanide-to-Lanthanide Energy Transfer in a Family of Site-Resolved [LnIIILnIII'] Heterometallic Complexes

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    The ligand H3 L (6-[3-oxo-3-(2-hydroxyphenyl)propionyl]pyridine-2-carboxylic acid), which exhibits two different coordination pockets, has been exploited to engender and study energy transfer (ET) in two dinuclear [LnIII LnIII '] analogues of interest, [EuYb] and [NdYb]. Their structural and physical properties have been compared with newly synthesised analogues featuring no possible ET ([EuLu], [NdLu], and [GdYb]) and with the corresponding homometallic [EuEu] and [NdNd] analogues, which have been previously reported. Photophysical data suggest that ET between EuIII and YbIII does not occur to a significant extent, whereas emission from YbIII originates from sensitisation of the ligand. In contrast, energy migration seems to be occurring between the two NdIII centres in [NdNd], as well as in [NdYb], in which YbIII luminescence is thus, in part, sensitised by ET from Nd. This study shows the versatility of this molecular platform to further the investigation of lanthanide-to-lanthanide ET phenomena in defined molecular systems

    Management Accounting for Healthy Nutrition Education: Meta-Analysis

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    Unequal economic growth shapes food systems. Nutrition problems incorporate inappropriate practices, so nutrition education is key to empowering consumers to choose healthy foods. However, increasing the accessibility of healthy diets is related to reducing the cost of nutritious foods. The accounting management of healthy nutrition should allow for optimal global decision-making. The evolution of scientific production and global research trends on this topic between 1968 and 2019 have been studied. Statistical and mathematical methods have been applied to 1738 documents from the Scopus database. The results provided data on the agents that participate in the development of the theme. Data reveal an exponential trend, especially in the previous decade, with more than 50% of scientific production. Future lines of research have been identified: investment in health systems; green label education; early impact of food insecurity; WIC (Women, Infants, and Children) nutrition education; food waste audit; and ecological footprint of food. The central contribution of the study has been to detect the main future directions of research, providing critical points that will allow us to identify the themes of future publications, in addition to providing an instrument for decision-making carried out by the research funding sponsors

    Managing ICT for Sustainable Education: Research Analysis in the Context of Higher Education

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    The use of information and communication technologies (ICTs) for the benefit of the environment favors the development of a sustainable education, which will help to train more responsible and aware students. The management of educational technology in the context of a sustainable higher education must achieve the internalization of ethics and the sustainable development of humanity. The main objective of this study is to, at a global level, examine the research during the period 2000–2019 on the management of ICTs for sustainable education in the context of higher education. Global research trends on this topic during the period 2000–2019 have been analyzed. Consequently, bibliometric techniques have been applied to a sample of 1814 articles selected from the Scopus database. The results provided data on the scientific productivity of the journal, authors, research institutions, and countries that contribute to the development of this topic. The evidence reveals an exponential trend, mainly in the last five years. In addition, current and future lines of research have been identified. Research at an international level presents a growing trend of publication that allows determination of the relevance of research on ICT management to achieve sustainable education in the context of higher education. This study makes it possible to establish the relationship between science, sustainability, and technology in higher education institutions, and to base the decision-making process for the driving agents of this area of knowledge

    Influence of the emotional alterations in the arterial stiffness index and cardiovascular risk of pre-hypertensive patients

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    Purpose: To determine the influence of emotional alterations in the arterial stiffness index and cardiovascular risk of pre-hypertensive patients.Methods: A cross-sectional study was carried out in 48 pre-hypertensive patients. Emotional alterations, global cardiovascular risk and arterial stiffness index were evaluated. The PPG technique was used to record the arterial pulse wave in the first finger of the lower right limb, using the ANGIODIN® digital plethysmograph.Results: Pre-hypertensive patients with emotional alterations had major Weight, Body Mass Index, systolic blood pressure, diastolic blood pressure and arterial stiffness index with respect to patients who did not find emotional alterations. In pre-hypertensive patients, 58.3% presented a positive Cornell test, 39.6% of them female, and 18.8% male. There was a significant relationship (p<0.001) between the presence of emotional disturbances and moderate cardiovascular risk.Conclusions: Emotional alterations in pre-hypertensive patients is associated with an increase in arterial stiffness and an increased global cardiovascular risk

    Distributive Nd-to-Yb Energy Transfer within Pure [YbNdYb] Heterometallic Molecules

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    Facile access to site-selective hetero-lanthanide molecules will open new avenues in the search of novel photophysical phenomena based on Ln-to-Ln′ energy transfer (ET). This challenge demands strategies to segregate efficiently different Ln metal ions among different positions in a molecule. We report here the one-step synthesis and structure of a pure [YbNdYb] (1) coordination complex featuring short Yb···Nd distances, ideal to investigate a potential distributive (i.e., from one donor to two acceptors) intramolecular ET from one Nd3+ ion to two Yb3+ centers within a well-characterized molecule. The difference in ionic radius is the mechanism allowing to allocate selectively both types of metal ion within the molecular structure, exploited with the simultaneous use of two β-diketone-type ligands. To assist the photophysical investigation of this heterometallic species, the analogues [YbLaYb] (2) and [LuNdLu] (3) have also been prepared. Sensitization of Yb3+ and Nd3+ in the last two complexes, respectively, was observed, with remarkably long decay times, facilitating the determination of the Nd-to-Yb ET within the [YbNdYb] composite. This ET was demonstrated by comparing the emission of iso-absorbant solutions of 1, 2, and 3 and through lifetime determinations in solution and solid state. The comparatively high efficiency of this process corroborates the facilitating effect of having two acceptors for the nonradiative decay of Nd3+ created within the [YbNdYb] molecule

    El impacto del Camino de Santiago en el ámbito académico: análisis de las tesis doctorales jacobeas en España

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    Este trabajo presenta un estudio inicial sobre el impacto del Camino de Santiago en la literatura científica, más específicamente, en las tesis doctorales. En concreto, se aporta un análisis descriptivo de los datos más significativos de todas aquellas tesis doctorales que guardan alguna relación con el Camino de Santiago y que han sido defendidas en España hasta finales del año 2021. En particular, los datos considerados incluyen el momento y lugar de defensa de cada tesis, así como sus descriptores temáticos —códigos UNESCO—. Para la recopilación de estos datos se ha consultado la base de datos TESEO, el repositorio del Ministerio de Educación, Cultura y Deporte en el que se almacenan todas las tesis doctorales españolas.Los autores agradecen el apoyo y financiación del Ministerio de Ciencia e Innovación a través de sus redes de excelencia (HAR2017-90883-REDC and RED2018-102518-T) y del proyecto PID2020-118906GB-I00, y de la Junta de Castilla y León – Consejería de Educación (BDNS 425389). Asimismo, este trabajo ha sido parcialmente financiado por el Fondo Social Europeo, a través de la concesión del contrato predoctoral de Silvia Díaz de la Fuente por medio de la Consejería de Educación de la Junta de Castilla y León

    Free PCR virus detection via few-layer bismuthene and tetrahedral DNA nanostructured assemblies

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    In this work we describe a highly sensitive method based on a biocatalyzed electrochemiluminescence approach. The system combines, for the first time, the use of few-layer bismuthene (FLB) as a platform for the oriented immobilization of tetrahedral DNA nanostructures (TDNs) specifically designed and synthetized to detect a specific SARS-CoV-2 gene sequence. In one of its vertices, these TDNs contain a DNA capture probe of the open reading frame 1 ab (ORF1ab) of the virus, available for the biorecognition of the target DNA/RNA. At the other three vertices, there are thiol groups that enable the stable anchoring/binding to the FLB surface. This novel geometry/approach enables not only the binding of the TDNs to surfaces, but also the orientation of the capture probe in a direction normal to the bismuthine surface so that it is readily accessible for binding/recognition of the specific SARS-CoV-2 sequence. The analytical signal is based on the anodic electrochemiluminescence (ECL) intensity of luminol which, in turn, arises as a result of the reaction with H2O2, generated by the enzymatic reaction of glucose oxidation, catalyzed by the biocatalytic label avidin-glucose oxidase conjugate (Av-GOx), which acts as co-reactant in the electrochemiluminescent reaction. The method exhibits a limit of detection (LOD) of 4.31 aM and a wide linear range from 14.4 aM to 1.00 μM, and its applicability was confirmed by detecting SARS-CoV-2 in nasopharyngeal samples from COVID-19 patients without the need of any amplification processPID2020-116728RB-I00, PID2020-116661RB-I00, PID2020-119352RB-I00, PDC2021-120782-C2, PID2022-138908NB-C31, CTQ2015-71955-REDT, S2018/NMT-434

    Probing the effect of ß-triketonates in visible and NIR emitting lanthanoid complexes

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    An isomorphous series of lanthanoid complexes containing tribenzoylmethanide (tbm) and 1,10-phenanthroline (phen) ligands has been synthesised and structurally characterised. These complexes, formulated as [Ln(phen)(tbm)3] (Ln = Eu3+, Er3+ and Yb3+), were compared with analogous dibenzoylmethanide (dbm) [Ln(phen)(dbm)3] complexes to investigate the effect of changing ß-diketonate to ß-triketonate ligands on the photophysical properties of the complex. The photophysical properties for the Eu3+ complexes were similar for both systems, whereas a modest enhancement was observed for Yb3+ and Er3+ moving from the dbm to the tbm complexes. A detailed study of the NIR photophysical properties was achieved by adapting the integrating sphere method for the calculation of overall quantum yields in the solid state

    Molecular epidemiology of an enterovirus A71 outbreak associated with severe neurological disease, Spain, 2016

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    Altres ajuts: We wish to thank I Bustillo, H del Pozo and P Higueras for their technical assistance. We also sincerely wish to thank all technical staff from microbiology departments and medical staff from paediatrics departments from all participating hospitals. Some of the samples are included in an ongoing project (PI15CIII-00020) which was supported by a grant by the Health Research System (AES).Introduction: Enterovirus A71 (EV-A71) is an emerging pathogen that causes a wide range of disorders including severe neurological manifestations. In the past 20 years, this virus has been associated with large outbreaks of hand, foot and mouth disease with neurological complications in the Asia-Pacific region, while in Europe mainly sporadic cases have been reported. In spring 2016, however, an EV-A71 outbreak associated with severe neurological cases was reported in Catalonia and spread further to other Spanish regions. Aim: Our objective was to investigate the epidemiology and clinical characteristics of the outbreak. Methods: We carried out a retrospective study which included 233 EV-A71-positive samples collected during 2016 from hospitalised patients. We analysed the clinical manifestations associated with EV-A71 infections and performed phylogenetic analyses of the 3'-VP1 and 3Dpol regions from all Spanish strains and a set of EV-A71 from other countries. Results: Most EV-A71 infections were reported in children (mean age: 2.6 years) and the highest incidence was between May and July 2016 (83%). Most isolates (218/233) were classified as subgenogroup C1 and 217 of them were grouped in one cluster phylogenetically related to a new recombinant variant strain associated with severe neurological diseases in Germany and France in 2015 and 2016. Moreover, we found a clear association of EV-A71-C1 infection with severe neurological disorders, brainstem encephalitis being the most commonly reported. Conclusion: An emerging recombinant variant of EV-A71-C1 was responsible for the large outbreak in 2016 in Spain that was associated with many severe neurological cases
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