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Differentiating five agrochemicals used in the treatment of intact olives by means of NIR spectroscopy, discriminant analysis and compliant class models
No full textThis paper deals with the application of near infrared spectroscopy (NIR) in a classification problem involving multiple classes in order to differentiate contaminated olives. A total of 452 samples, ripe and unripe, were treated with five different agrochemicals reproducing the traditional fumigation process in the olive tree. The main objective was to differentiate through a classification if the samples were or were not treated, but also, which chemical was used for each olive. Firstly, Partial Least Squares-Discriminant Analysis (PLS-DA) was performed to differentiate between untreated and treated samples. Then, two novel chemometric approaches, a classification one and a modelling one, were applied for ripe and unripe olives, achieving good results and determining with which chemical were the olives sprinkled with. For the classification of the samples in the six different classes (untreated olives, or treated with one of the five agrochemicals), an Automatic Hierarchical Model Builder (AHIMBU) was used, applying sequential binary PLS-DAs. Nevertheless, for the modelling approach, a compliant model, PLS2-CM, also based on PLS, was used with two different codifications for the classes: i) the classic and well-known One Versus All (OVA), and ii) the Error Correction Output Code (ECOC) optimal matrix. The final global results were evaluated using the Diagonal Modified Confusion Entropy (DMCEN) index, which ranges between 0 and 1, and is very sensitive to changes in the sensitivity–specificity matrices (note that the lower the DMCEN, the better the classification is). The best DMCEN value in prediction for unripe olives, 0.4898, was obtained for the PLS2-CM-ECOC, while 0.6937 and 0.7705 DMCEN values were obtained for AHIMBU and PLS2-CM-OVA, respectively. For the case of the ripe samples, the DMCEN values in prediction were better than the ones for the unripe olives: 0.6016, 0.5051, and 0.4166, for AHIMBU, PLS2-CM-OVA and PLS2-CM-ECOC, respectively. In every case, the best DMCEN has been obtained with the PLS2-CM-ECOC procedure.This work has been funded by the Ministerio de Industria, Comercio y Turismo under Project ESPECTROLIVE (AEI-010500–2023-232)
Influence of specimen size and fiber content on fatigue flexural strength of high-performance fiber-reinforced concrete
No full textThis paper studies the impact of specimen size and fiber content on the flexural fatigue response of high-performance fiber-reinforced concrete (HPFRC). For this purpose, six series of prismatic specimens were fabricated, considering two sizes (75 × 75 × 300 mm and 150 × 150 × 600 mm) and three fiber contents (0.3%, 0.6% and 1%). Twelve specimens from each series were tested in flexural fatigue under the same relative stress levels. It was sought to explain the variations in fatigue response through the observation of the mesostructure. In particular, correlations were established between the fiber distribution and the fatigue strength of all series. The results reveal that the parameter that most influences the ultimate static bending strength (σult) is the fiber volume in the central region of the specimens (Vfib), with the orientation having a much lower weight. In contrast, the opposite is true for cyclic tests. Since the fatigue stress levels were calculated in relation to σult of each series, the influence of Vfib is negligible. In this case, a clear correlation between fiber orientation with the longitudinal axis and fatigue strength is observed. Specifically, the orientation factor ηX accurately predicts both the characteristic fatigue life and the rate at which damage progresses in the main macrocrack.The authors are grateful for the financial support of the Spanish Ministerio de Economía y Competitividad (grant no. PID2019–110928RB-C32) and the Spanish Ministerio de Ciencia, Innovacion ´ y Universidades (grant no. FPU19/02685)
Targeted 1−H-NMR wine analyses revealed specific metabolomic signatures of yeast populations belonging to the Saccharomyces genus
No full textThis study aimed to explore the non-volatile metabolomic variability of a large panel of strains (44) belonging to the Saccharomyces cerevisiae and Saccharomyces uvarum species in the context of the wine alcoholic fermentation. For the S. cerevisiae strains flor, fruit and wine strains isolated from different anthropic niches were compared. This phenotypic survey was achieved with a special focus on acidity management by using natural grape juices showing opposite level of acidity. A 1H NMR based metabolomics approach was developed for quantifying fifteen wine metabolites that showed important quantitative variability within the strains. Thanks to the robustness of the assay and the low amount of sample required, this tool is relevant for the analysis of the metabolomic profile of numerous wines. The S. cerevisiae and S. uvarum species displayed significant differences for malic, succinic, and pyruvic acids, as well as for glycerol and 2,3-butanediol production. As expected, S. uvarum showed weaker fermentation fitness but interesting acidifying properties. The three groups of S. cerevisiae strains showed different metabolic profiles mostly related to their production and consumption of organic acids. More specifically, flor yeast consumed more malic acid and produced more acetic acid than the other S. cerevisiae strains which was never reported before. These features might be linked to the ability of flor yeasts to shift their metabolism during wine oxidation.« This study received financial support from the French government in the framework of the IdEX Bordeaux University "Investments for the Future" program/GPR Bordeaux Plant Sciences ». PM received a financial support from Aquitaine lander: program MEGAVIP, 2020–2023. This work was supported by the Bordeaux Metabolome Facility and MetaboHUB (ANR-11-INBS-0010 project)
Poetica et theatrum. La funcionalidad teatral de los villancicos del primer Cancionero de Juan del Encina
No full textEste trabajo examina la presencia de la poesía de Juan del Encina en su primera producción teatral, publicada en su Cancionero de 1496. El objetivo es establecer relaciones entre la poesía y el teatro del autor salmantino y señalar la funcionalidad dramatúrgica que presentan las composiciones poéticas musicales insertas en sus ocho églogas teatrales sacras y profanas. Se recurrirá, para ello, a la semiótica teatral, que incide en la dualidad del texto teatral como texto literario y texto espectacular.This paper examines the presence of Juan del Encina’s poetry in his first theatrical production, published in his Cancionero of 1496. The aim is to establish relations between his poetry and his theatre and to point out the dramaturgical functionality of his poetic musical compositions in his eight sacred and profane theatrical eclogues. In order to do so, I will use the theatrical semiotics, which defends the duality of the theatrical text as a literary text and a spectacular text
Analysis of the static and dynamic elastic moduli of a one-coat rendering mortar with laboratory and in situ samples
No full textAlthough the compressive strength is the most commonly used property to characterize mortars, it has limited representativeness in real-world applications. The deformation properties of mortars, specifically the elastic modulus, are responsible for masonry behavior. However, there is currently no standard method for determining the elastic modulus of mortars and no consensus on the best approach. Therefore, the aim of this paper is to obtain both static and dynamic moduli of a one-coat rendering mortar following the standards for calculating them on concrete specimens and verify their validity. The static modulus was determined under compression by adapting the standard for concrete specimens (EN-1352) to mortars using two gauges, and under the flexural tensile test following the standard EN-1015–11. The dynamic modulus was calculated by measuring the fundamental resonant frequencies of longitudinal and transverse vibration modes, adapting the American standard for concrete (ASTM C215) for mortar. The tests were performed on both standardized and non-standardized prismatic specimens, as well as in situ samples at various ages. The results indicated that dynamic modulus obtained from the longitudinal vibration mode was higher than that from the transverse mode, but differences were smaller using a uniaxial accelerometer than with a triaxial accelerometer. The dynamic modulus exhibited a slightly higher value and lower dispersion than the static modulus. Both moduli decreased with time and were easily correlated through linear regressions. Additionally, both moduli were correlated with flexural and compressive strength values. In situ samples had lower elastic moduli, but the compaction procedure in real works differs from laboratory tests. In summary, it was demonstrated that the procedures for calculating dynamic and static elastic moduli in concrete can be applied to mortar samples, and their effectiveness was confirmed
Reliability of the palaeomagnetic signal recorded in a lava flow erupted on 4 December 2021 in La Palma (Canary Islands, Spain)
No full textA basaltic lava flow erupted from the Tajogaite volcano on 4 December 2021, in La Palma (Canary Islands, Spain) was sampled to find out to what extent reliable and correct information on both intensity and direction of the Earth's magnetic field can be obtained from the palaeomagnetic signal recorded in a lava flow which erupted under known conditions. Samples were taken every few centimetres across a flow up to a total of 27 oriented cores. Palaeomagnetic experiments showed a strong viscous overprint in many samples. Nevertheless, the mean palaeomagnetic direction obtained agrees well with the actual value from IGRF-13. Rock magnetic experiments were performed to obtain additional information about the quality and reliability of the results and the reasons for unsuccessful determinations. Analysis of mostly irreversible thermomagnetic curves showed that the carriers of remanence were magnetite and titanomagnetite of low and/or intermediate Curie-temperature. Hysteresis parameter ratios showed a pronounced variability across the flow. Analyses of frequency dependent susceptibility, IRM acquisition coercivity spectra and FORCs showed a noticeably presence of very low coercivity grains (multidomain and superparamagnetic-single domain boundary). Multimethod palaeointensity experiments were performed with the Thellier-Coe, multispecimen and Tsunakawa-Shaw methods. Only three of 25 cores from the flow yielded successful Thellier-Coe determinations, in agreement with the expected field value of 38.7 μT (IGRF-13). However, palaeointensities of 60 per cent of the specimens agree with the expected value performing an informal analysis without considering criteria thresholds. Four of six Tsunakawa-Shaw determinations performed on samples from the flow yielded correct results, but three multispecimen determinations providing apparently successful determinations largely underestimate the expected field intensity. Combination of three Thellier-Coe and four Tsunakawa-Shaw successful determinations yields a multimethod palaeointensity result B = (36.9 ± 2.0) μT in good agreement with the expected field intensity.This work was funded by project PID2019-105796GB-100/AEI/10.13039/501100011033 (Spanish Agencia Estatal de Investigación), project BU037P23 (Junta de Castilla y León and the European Research and Development Fund, ERDF) and JSPS KAKENHI Grant No. 21H01171. We thank Antonio González (Cabildo de La Palma) for his invaluable support and help during our visit to the island of La Palma. We also wish to thank Dr Eugenio Fraile Nuez (IEO-CSIC) for providing us the submarine lava flow samples. We also wish two thank two anonymous reviewers for helpful comments
Insights into the anticancer photodynamic activity of Ir(III) and Ru(II) polypyridyl complexes bearing β-carboline ligands
No full textIr(III) and Ru(II) polypyridyl complexes are promising photosensitizers (PSs) for photodynamic therapy (PDT)
due to their outstanding photophysical properties. Herein, one series of cyclometallated Ir(III) complexes and
two series of Ru(II) polypyridyl derivatives bearing three different thiazolyl-β-carboline N^N′ ligands have been
synthesized, aiming to evaluate the impact of the different metal fragments ([Ir(C^N)2]
+ or [Ru(N^N)2]
2+) and
N^N’ ligands on the photophysical and biological properties. All the compounds exhibit remarkable photo
stability under blue-light irradiation and are emissive (605 < λem < 720 nm), with the Ru(II) derivatives dis
playing higher photoluminescence quantum yields and longer excited state lifetimes. The Ir PSs display pKa
values between 5.9 and 7.9, whereas their Ru counterparts are less acidic (pKa > 9.3). The presence of the
deprotonated form in the Ir-PSs favours the generation of reactive oxygen species (ROS) since, according to
theoretical calculations, it features a low-lying ligand-centered triplet excited state (T1 = 3
LC) with a long
lifetime. All compounds have demonstrated anticancer activity. Ir(III) complexes 1–3 exhibit the highest cyto
toxicity in dark conditions, comparable to cisplatin. Their activity is notably enhanced by blue-light irradiation,
resulting in nanomolar IC50 values and phototoxicity indexes (PIs) between 70 and 201 in different cancer cell
lines. The Ir(III) PSs are also activated by green (with PI between 16 and 19.2) and red light in the case of
complex 3 (PI = 8.5). Their antitumor efficacy is confirmed by clonogenic assays and using spheroid models. The
Ir(III) complexes rapidly enter cells, accumulating in mitochondria and lysosomes. Upon photoactivation, they
generate ROS, leading to mitochondrial dysfunction and lysosomal damage and ultimately cell apoptosis.
Additionally, they inhibit cancer cell migration, a crucial step in metastasis. In contrast, Ru(II) complex 6 exhibits moderate mitochondrial activity. Overall, Ir(III) complexes 1–3 show potential for selective light-controlled cancer treatment, providing an alternative mechanism to chemotherapy and the ability to inhibit lethal cancer cell dissemination.This work was supported by the Ministerio de Ciencia e Innovacion/ ´ Agencia Estatal de Investigacion ´ of Spain (MCIN/AEI/10.13039/ 501100011033) (projects PID2021-127187OB-C21, PID2021- 128569NB-I00, PID2020-115910RB-I00, PID2021-127187OB-C22, and CEX2019-000919-M). PhD students acknowledge their predoctoral grants to Universidad de Burgos (J.S.V., 2019/00002/008/001), Uni versity of Girona (C.B., IFUdG 2021), Generalitat de Catalunya (E.Z., AGAUR; 2021 FI_B 01036) and Generalitat Valenciana (I. S.D., CIACIF/ 2021/438), respectively
Límites al derecho de autor en favor de bibliotecas y minería de textos y datos: estudio comparado desde Cuba y España
No full textLa tesis se desarrolla en el marco del Convenio de Cotutela firmado entre las Universidades de Burgos y La Habana. La investigación tiene como objeto de estudio dos límites al derecho de autor, a saber: las excepciones en favor de bibliotecas y el nuevo límite de minería de textos y datos. Respondiendo a las exigencias metodológicas del Convenio el informe sistematiza el trabajo realizado por la investigadora durante dos períodos. El primero, comprendido entre los años 2020-2021, analiza las limitaciones al derecho de autor en favor de bibliotecas en el sistema jurídico cubano, con referencias a específicos aspectos doctrinales, normativos y jurisprudenciales de España que permiten examinar la realidad de Cuba con mayor solidez, objetividad y crítica constructiva. El segundo desarrollado en España entre los años 2022-2024 estudia el límite de minería de textos y datos. El examen aborda aspectos técnicos de la actividad minera hasta focalizar el estudio en el nuevo límite TDM en la Directiva del Mercado Único Digital y su transposición en España. Bajo esta concepción jurídico -comparada se establecen tres centros de interés en la investigación. El primero, encaminado a sistematizar nociones básicas y principios rectores del derecho de autor en el nuevo contexto tecnológico con la intención de guiar el estudio de lo general a lo particular y, establecer las bases de los constructos que se formulan a posteriori sobre el objeto de estudio. El segundo enfocado en el estudio técnico-jurídico de las limitaciones al derecho de autor en favor de bibliotecas y la TDM, sin desconocer que el centro de toda actividad creadora es el autor y por ello el sacrificio exigido debe ser mínimo y debidamente justificado. Y el tercero orientado a establecer las pautas que, en criterio de la autora, deben seguir las normas al momento de regular las limitaciones objeto de estudio. El abordaje de los referentes teóricos y normativos de ambas excepciones, a la luz de los sistemas de inteligencia artificial y las demandas del mercado único digital, permitió fundamentar una propuesta de lege ferenda para la reforma del sistema de límites en favor de bibliotecas y de TDM en Cuba, objetivo fundamental de la investigación
The European Public Prosecutor’s Office and Environmental Crime: Further Competence in the Near Future?
No full textThis article envisages the possible extension of the European Public Prosecutor’s Office’s competences in the field of environmental protection. The author first presents an overview of the Office’s competences under the current legislation and, second, analyses suggestions on extending these competences specifically to the field of environmental crime. The case is made that a stronger, more comprehensive scope of competence for the EPPO would strengthen its position in the EU. This warrants an extension of the Office's jurisdiction to other types of crime, especially in the fight against cross-border crime such as environmental crime.This article is part of the project “New scenario of European and national criminal procedure in the Member States after the introduction of the European Public Prosecutor’s Office (EPPO)”, PRX22/00437; the project is financed by the Spanish Ministry of Universities whose support is gratefully acknowledged and supervised by Professor Ester Herlin-Karnell at the University of Gothenburg (Sweden). The article also includes involvement of the projects “Civil and criminal Procedural Law from the perspective of the European Union: the consolidation of the Area of Freedom, Security and Justice”, PID2021-124027NB-100 and “Mutual recognition 2.0: effective, coherent, integrative and proportionate application of judicial cooperation instruments in criminal matters (MR2.0)”, JUST-2022-JCOO-101089060
Using Integrated Multimodal Technology: A Way to Personalise Learning in Health Science and Biomedical Engineering Students
No full textMonitoring the learning process during task solving through different channels will facilitate a better understanding of the learning process. This understanding, in turn, will provide teachers with information that will help them to offer individualised education. In the present study, monitoring was carried out during the execution of a task applied in a self-regulated virtual environment. The data were also analysed using data fusion techniques. The objectives were as follows: (1) to examine whether there were significant differences between students in cognitive load (biomarkers: fixations, saccades, pupil diameter, galvanic skin response—GSR), learning outcomes and perceived student satisfaction with respect to the type of degree (health sciences vs. engineering; and (2) to determine whether there were significant differences in cognitive load metrics, learning outcomes and perceived student satisfaction with respect to task presentation (visual and auditory vs. visual). We worked with a sample of 31 university students (21 health sciences and 10 biomedical engineering). No significant differences were found in the biomarkers (fixations, saccades, pupil diameter and GSR) or in the learning outcomes with respect to the type of degree. Differences were only detected in perceived anxiety regarding the use of virtual laboratories, being higher in biomedical engineering students. Significant differences were detected in the biomarkers of the duration of use of the virtual laboratory and in some learning outcomes related to the execution and presentation of projects with respect to the variable form of the visualisation of the laboratory (visual and auditory vs. visual). Also, in general, the use of tasks presented in self-regulated virtual spaces increased learning outcomes and perceived student satisfaction. Further studies will delve into the detection of different forms of information processing depending on the form of presentation of learning tasks.Project “Voice assistants and artificial intelligence in Moodle: a path towards a smart university” SmartLearnUni. Call 2020 R&D&I Projects—RTI Type B. MINISTRY OF SCIENCE AND INNOVATION AND UNIVERSITIES. STATE RESEARCH AGENCY. Government of Spain, grant number PID2020-117111RB-I00”. Specifically, in the part concerning the application of multichannel eye tracking technology with university students and Project “Specialized and updated training on supporting advance technologies for early childhood education and care professionals and graduates” (eEarlyCare-T) grant number 2021-1-ES01-KA220-SCH-000032661 funded by the EUROPEAN COMMISSION. In particular, the funding has enabled the development of the e-learning classroom and educational materials