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Green extraction of isoflavones from okara using subcritical water: Kinetics, optimization, and comparison with other water-based sustainable methods
No full textWater has been explored as a green extraction agent for isoflavone extraction from okara. First, subcritical water (subW) was explored using two different okaras: (1) washed and dried (OKW) and (2) non-pretreated (OKC). Genistein family was the most abundant, with very low quantities in the glycitein family. Kinetic data revealed interconversion of malonyl-glycosides to β-glycosides in subW, with increasing degradation rate constants for all isoflavones with temperature. A maximum of 1229 μg isoflavone/g of dried okara was obtained at 120 °C after 30 min for OKC. Microwave (MAE) and ultrasound (UAE) technologies achieved 72.8 % and 75.4 %, of the yield of subW. Productivity at the maximum was of 41.0, 82.5 and 92.8 μg isoflavone/g dry okara min for subW, MAE, UAE. However, higher fraction of the more bioavailable forms β-glycoside + aglycone was obtained by subW.This work was supported by the Agencia Estatal de Investigación [grant numbers PID2022-136385OB-I00, PDC2022–133443-I00, TED2021-129311B-I00], Junta de Castilla y León (JCyL), and European Regional Development Fund (ERDF) [grant number BU027P23]. A. E. Illera postdoctoral contract was funded by BU027P23. P. Barea and H. Candela pre-doctoral contracts are funded by JCyL and the European Social Fund (ESF) [ORDEN EDU/1868/2022, ORDEN EDU/1009/2024, respectively]. The R Melgosa contract was funded by a Beatriz Galindo Research Fellowship [BG20/00182]
Optimization of concrete containing wind-turbine wastes following mechanical, environmental and economic indicators
Full text linkThe decommissioning of wind farms produces two primary waste materials: Recycled Concrete Aggregate (RCA) derived from the foundation concrete, and Raw-Crushed Wind-Turbine Blade (RCWTB) obtained through the crushing and sieving of the blades. Incorporating these materials into concrete enhances sustainability and, in some cases, improves mechanical properties while reducing the final environmental impact and cost compared to conventional concrete. A comprehensive characterization of the mechanical properties of concrete mixtures with varying RCA (0–100%) and RCWTB (0–10%) contents was conducted, these mixes being designed with increased water and admixture contents to compensate for the expected loss of workability caused by the addition of these waste materials. A Life-Cycle Assessment (LCA) and cost evaluation were also performed. The optimization of these mixtures was addressed using the Response Surface Method (RSM). The optimization process revealed that intermediate combinations of RCA (50%) and RCWTB (5%) yielded maximum flexural-tensile properties. However, achieving optimal performance proved more challenging when simultaneous optimization included compressive strength and deformability properties, such as modulus of elasticity and Poisson’s coefficient. For these properties, the optimal mix incorporated 88% RCA and 0% RCWTB. The RSM analysis demonstrated the feasibility of incorporating both RCA and RCWTB into concrete mixtures, mainly intended to work under bending stresses, but it also highlighted the complexities of achieving optimal performance when all mechanical properties were simultaneously considered. This research underscores the potential for these recycled materials to contribute to more sustainable concrete production while addressing the trade-offs in mechanical performance optimization
In silico exploration of graphene nanoflakes: From DFT simulations to machine learning-driven toxicity predictions
Full text linkThe present theoretical work provides a ground-breaking and comprehensive study of graphene nanoflakes integrating Density Functional Theory (DFT) simulations, toxicity predictions and a machine learning approach. The properties of graphene nanoflakes as a function of size, shape, and symmetry are systematically analysed using DFT calculations. The interaction of these nanoflakes with human proteins and cell membranes, considered as Molecular Initiating Events for diverse Adverse Outcome Pathways, is explored to infer potential toxicity effects. Leveraging the generated data, machine learning models were developed to predict flake properties and biological interactions. A single score representing the biological interaction or impact of graphene nanoflakes on both proteins and plasma membranes is assigned to each evaluated nanoflake to infer its potential toxicity. Our multiscale approach bring valuable insights into the structure-property-toxicity relationships of graphene nanoflakes, paving the way for their safe and efficient design and application.This work was funded by European Union H2020 Program (H2020-NMBP-TO-IND-2020-twostage-DIAGONAL-GA- 953152) and Junta de Castilla y León (Spain, project NANOCOMP - BU058P20). We also acknowledge SCAYLE (Supercomputación Castilla y León, Spain) for providing supercomputing facilities. The statements made herein are solely the responsibility of the authors. Authors declare no competing interests
Material extrusion additive manufacturing of Acrylonitrile-Butadiene-Styrene: Experiments and anisotropic model for the orientation angle
No full textThe yield stress as a function of both strain rate and orientation angle was measured for material extrusion additively manufactured (ME-AM) Acrylonitrile-Butadiene-Styrene (ABS). Unidirectional test specimens were extracted by waterjet-cutting at different orientation angles from ME-AM processed plates. By printing rectangular plates, a strand trajectory of constant length can be applied. Thus, the thermo-mechanical history of the material was as similar as possible across the plate. By determining an average sample porosity using Archimedes’ principle, yield stress values could be compensated for the voids present in ME-AM specimen. A time- and orientation-dependent model, which combines an Eyring flow rule with Hill anisotropy, was used to describe the yield stresses as a function of strain rate and orientation angle. The model uses a factorizable approach, i.e. both effects are decoupled, which simplifies the determination of model parameters. This anisotropic continuum-based viscoelastic Eyring-Hill model is able to adequately predict the complex experimental yield stress behavior, which is a challenging task. Scanning Electron Microscope fractography revealed macroscopically more ductile behavior due to failure in the strand direction. Macroscopically brittle behavior was related to inter-strand failure. The present study is an important step towards the prediction of structural integrity of ME-AM parts, as time- and orientation-dependency are also important in creep and fatigue behavior
Información de sostenibilidad en la universidad: Informe de Impacto Medioambiental de la Universidad de Burgos
Full text linkEste Trabajo de Fin de Máster analiza el proceso de elaboración del Informe de Impacto Medioambiental
que deben elaborar las universidades españolas de acuerdo con la Ley Orgánica del Sistema
Universitario. Su objetivo principal es examinar los factores que han influido en la creación de dicho
informe y analizar cómo este proceso puede contribuir a mejorar la divulgación de la información de
sostenibilidad y reforzar la estrategia institucional de la universidad. Para ello, se ha realizado un estudio
de caso de la Universidad de Burgos, a través de análisis documental, observación participativa y
revisión de fuentes internas. Los resultados evidencian avances significativos en la divulgación de la
información, aunque persisten carencias en la estandarización de indicadores y en la implicación de los
grupos de interés.This Master’s Thesis examines the development of the Environmental Impact Report that Spanish
universities must produce according to the Organic Law of the University System. Its main objective is
to examine the factors that have influenced the production of this report and analyse how this process
can improve sustainability disclosure and enhance the university’s sustainability strategy. The thesis
develops a case study of the University of Burgos, informed by documentary analysis, participatory
observation, and internal data review. The findings reveal significant progress in disclosing information,
though gaps remain in standardizing indicators and promoting stakeholder engagement
Disminución de ingresos por complicaciones con la preeclampsia
Full text linkIncluye el texto del trabajo y la presentaciónDurante el periodo de embarazo pueden surgir varias patologías derivadas de este. La
preeclamsia es una de estas enfermedades, que afectará a un 7%-10% de las mujeres
gestantes. Esta dolencia se define como el aumento de la tensión arterial derivada del
embarazo, además de presencia de proteinuria
Gestión de procesos y gestión de memoria no virtual (herramientas y problemas resueltos)
No full textExiste un importante número de sistemas informáticos para los que se han diseñado distintos sistemas operativos que puedan hacer uso de todos sus componentes.
Además, los sistemas operativos han evolucionado con el objetivo de convertirse en el intermediario entre el usuario y la máquina, evitando al usuario la complejidad del hardware. Y en su evolución se han separado sus diferentes funcionalidades, entre las que destacan la gestión de ciertos elementos, como son los procesos y la memoria.
Para su gestión se han desarrollado una serie de algoritmos que han ido evolucionando a lo largo del tiempo, y que aún siguen en constante evolución.
Sin embargo, las diferentes funcionalidades del sistema operativo se basan en conceptos que, en muchas ocasiones, resultan constantes a lo largo de su evolución, aunque siempre directamente dependientes de la tecnología.
Por ello, el contenido de esta publicación está orientado a dotar al lector de la capacidad de comprender y practicar estos conceptos a través de una serie herramientas que simulan el comportamiento del hardware y de sus procesos de gestión, mediante diferentes algoritmos.
Los dos aspectos fundamentales a desarrollar serán la Gestión de Procesos y la Gestión de Memoria No Virtual.
Además, en el desarrollo de la presente publicación no se tratará de explicar de forma detallada cómo funcionan cada uno de los algoritmos utilizados mediante explicaciones teóricas, salvo algunas indicaciones básicas. Por contra, se tratará de dar ejemplos de todos y cada uno de los algoritmos utilizados, combinando ambos aspectos de la Gestión.
Las herramientas han ido evolucionando con la colaboración de los alumnos de la asignatura de "Sistemas Operativos" de primer curso del Grado en Informática" de la Universidad de Burgos, entre los años 2012 y 2024.
En cuanto a su desarrollo, están implementadas en bash sobre linux, linux por ser el sistema operativo utilizado a lo largo de la asignatura, y bash por ser uno de los lenguajes de scripting que utiliza linux. Esta elección no se basó en usar el mejor sistema operativo, ni tampoco en usar el mejor de los lenguajes de programación, sino en usar los recursos más íntimamente relacionados con la asignatura, tal y como estaba definida en ese periodo de tiempo.
Los ámbitos de utilización de las herramientas y la correspondiente documentación son la docencia y su uso por parte de los alumnos de la asignatura, para mejorar su comprensión y facilitar su estudio, así como el ámbito profesional, para analizar las ventajas y desventajas de cada uno de los algoritmos utilizados
Detection of Nutrients and Contaminants in the Agri-Food Industry Evaluating the Probabilities of False Compliance and False Non-Compliance Through PLS Models and NIR Spectroscopy
Full text linkNIR spectroscopy has become one of the most prominent techniques in the food industry due to its easy and fast use. Coupled with PLS, it is a well-established method for determining nutrients, contaminants, or adulterants in foods. Nevertheless, it is not common when calculating the capability of detection or discrimination given a target/permitted value, providing probabilities of false non-compliance (α) or false compliance (β). That is exactly the main purpose of this work, where a single procedure using the accuracy line to evaluate these figures of merit by generalizing ISO 11843 when using NIR-PLS in real scenarios in agri-food industries is shown. Nevertheless, it is a completely general procedure and can be used in any analytical context in which a PLS calibration is applied. As an example of its versatility, several analytical determinations were performed using different common food matrices in the agri-food industry (butter, flour, milk, yogurt, oil, and olives) for the quantification of protein, fat, salt, and two agrochemicals. Some results were a detection capability of 5.2% of fat in milk, 1.20 mg kg−1 for diflufenican, and 2.34 mg kg−1 for piretrin in olives when maximum limits were established at 5%, 0.6 mg kg−1, and 0.5 mg kg−1 respectively. Also, 1.02% for salt in butter and 11.45%, 3.78%, and 2.65% for protein in flour, milk, and yogurt, respectively, were obtained when minimum limits were established at 1.2%, 12%, 4%, and 3% respectively. In all cases α = β = 0.05.The authors thank Lugar daVeiga S.L.L., Lácteos De Moeche S.L., and Fundación CITOLIVA/INOLEO for allowing the measurements in their facilities and the entities for the financial support