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Kinetics of extraction and degradation of pectin derived compounds from onion skin wastes in subcritical water
No full textIn this work the valorization of onion skin wastes (OSW) as a source of the pectic oligosaccharides (POS), prebiotic hydrocolloids, using subcritical water (SubW) was thoroughly studied and modeled (using the Panchev's model) in a batch extractor at temperatures up to 165 °C and extraction times up to 180 min. The extraction of pectin derived compounds was notably sensitive to both variables, with the most favorable extraction rates occurring within a severity factor (logR0) range of 2.8–3.1. The highest recovery, 32 g of OGalA per 100 g of raw material, was achieved at 135 °C for 100 min. This process yielded various families of compounds categorized by their weight average molecular weight (Mw), with 85 kDa being the most prevalent, followed by 27, 17, and 7 kDa. The changes in Mw as a function of time and temperature was modeled using the Emsley equation, which enabled the prediction of POS molecular weight based on extraction conditions, as well as the calculation of the energy of activation for pectin derived compounds degradation (116 ± 2 kJ/mol). Additionally, along with the loss in molecular weight, the presence of degradation products such as formic acid and furfural increased with the intensity of the extraction conditions. In summary, the hydrothermal extraction conducted at temperatures between 125 and 135 °C facilitated the retrieval of POS with MW ranging from 7 to 85 kDa. This stands in contrast to the high MW (>300 kDa) and linear pectin obtained through conventional acid-water extraction processes.This work was supported by the Agencia Estatal de Investigación (AEI) though projects PID2020-116716RJ-I00/AEI/10.13039/501100011033, PID2022-136385OB-I00/AEI/10.13039/501100011033 and TED2021-129311B-I00. Ó. Benito-Román's post-doctoral contract was funded by AEI through project PID2020-116716RJ-I00. R. Melgosa's contract was funded by a Beatriz Galindo Research Fellowship [BG20/00182]; A.E. Illera's post-doctoral contract was funded by Junta de Castilla y León and ERDF through project BU027P23
Teaching self-criticism and peer-critique skills to engineering students through a temporal survey-based program
No full textIntroduction: Engineering students should develop critical-thinking skills and insist on appropriate performance levels both from themselves and from their colleagues during their training. In doing so, they will adopt critical attitudes toward their own and others’ work. This will help them to successfully perform their future professional work with the highest standards.
Methods: In this research, peer- and self-assessments of in-class presentations through a survey-based program were used to analyze the development of critical-thinking skills among engineering students. The program included two key features: firstly, formative assessments were repeatedly conducted over time; secondly, teachers’ ratings were provided to students as comparative benchmarks. This approach encouraged students to reflect on their ratings over time using the reference of the teacher.
Results: From a general perspective, the analysis of survey responses showed that students assigned lower ratings in assessments conducted at a later stage, despite receiving higher ratings from their teachers over time. Therefore, students became more demanding throughout the experience in spite of the increased quality of their work according to the teachers’ assessments. Moreover, students tended to closely attune their evaluations to their teachers’ ratings. Comparing peer- and self-assessments, it was noted that students were more demanding toward the work of their peers in the long term, and especially their ability to explain concepts, than they were toward their own work. Nevertheless, high temporary increases were observed in students’ own self-assessments of presentation-file quality. Finally, students did not conduct overall assessments with the same level of demand as their teachers at any time during the experience.
Discussion: The results demonstrate that this program and similar initiatives are useful to help engineering students to develop critical-thinking skills and to broaden their expectations with respect to their own and their colleagues’ work. However, other relevant aspects could be evaluated in lengthier programs, such as whether the students’ levels of critical thinking and expectations are maintained when the comparative reference of a teacher’s assessment is unavailable.The author(s) declare that financial support was received for the research, authorship, and/or publication of this article. The authors wish to express their gratitude to the Junta de Castilla y León (Regional Government) and ERDF [grant number BU066-22]; and the University of Burgos for the funding program “Convocatoria de Ayudas a Grupos de Innovación Docente reconocidos para la elaboración de materiales docentes para los años 2023 y 2024.
Influence of yeasts on wine acidity: new insights into Saccharomyces cerevisiae
No full textClimate change is strongly affecting the winemaking sector, notably by decreasing wine acidity due to lower malic acid levels in the grapes. Wine-related microorganisms can greatly affect the organic acid contained in wines as they are able to metabolise or synthesise different acids. Major advances in biochemistry, ecophysiology and molecular biology have led to numerous yeast strains being selected for that have specific oenological properties, including acidity modulation. The yeast Saccharomyces cerevisiae is the most extensively studied species, harbouring both malic acid-consuming and producing strains which are of interest in various vinification itineraries. Yeast-derived acidification of wines can indeed be achieved via malic acid production by S. cerevisiae, as well as via lactic acid production by Lachancea thermotolerans. Co-fermentations of these two species become promising tools to manage wine acidity while ensuring fermentation completion and wine quality. Deacidification of wines via malic acid consumption is relevant in cooler winemaking regions, and/or for shortening malolactic fermentation and thereby increasing wine stability. This review delivers an in-depth overview of the effect of various oenologically relevant yeasts on wine acidity, with a focus on the latest findings on novel (de)acidifying S. cerevisiae strains
Meta-analysis of randomized controlled trials and single-case designs on the efficacy of functional analytic psychotherapy.
No full textFunctional analytic psychotherapy (FAP) is an approach based on contextual behavioral principles with a focus on interpersonal issues. This review quantitatively synthesized the evidence on the efficacy of FAP in addressing various clinical outcomes. A systematic literature search was conducted. After study selection, coding, and data extraction, outcomes were meta-analyzed using a random-effects model. Subgroup analyses, metaregressions, and bias assessments were performed. Seventy studies met the inclusion criteria. Results from single-case designs showed significant improvements in idiographic clinically relevant behaviors (i.e., avoidance of intimacy and conflict vs. engaging in intimacy-promoting behaviors, assertive expression of feelings and needs). Controlled group studies showed robust results for depression and anxiety symptoms. No significant changes were found for anger, experiential avoidance, and mindfulness. Thus, our results provide empirical support for FAP in the treatment of interpersonal behaviors and internalizing symptoms, although bias in the included studies may limit these findings
Specific Design of a Self-Compacting Concrete with Raw-Crushed Wind-Turbine Blade
No full textWind-turbine blades pose significant disposal challenges in the wind-energy sector due to the increasing demand for wind farms. Therefore, this study researched the revaluation of Raw-Crushed Wind-Turbine Blade (RCWTB), obtained through a non-selective blade crushing process, as a partial substitute for aggregates in Self-Compacting Concrete (SCC). The aim was to determine the most adequate water/cement (w/c) ratio and amount of superplasticizing admixtures required to achieve adequate flowability and 7-day compressive strength in SCC for increasing proportions of RCWTB, through the production of more than 40 SCC mixes. The results reported that increasing RCWTB additions decreased the slump flow of SCC by 6.58% per 1% RCWTB on average, as well as the compressive strength, although a minimum value of 25 MPa was always reached. Following a multi-criteria decision-making analysis, a w/c ratio of 0.45 and a superplasticizer content of 2.8% of the cement mass were optimum to produce SCC with up to 2% RCWTB. A w/c ratio of 0.50 and an amount of superplasticizers of 4.0% and 4.6% were optimum to produce SCC with 3% and 4% RCWTB, respectively. Concrete mixes containing 5% RCWTB did not achieve self-compacting properties under any design condition. All modifications of the SCC mix design showed statistically significant effects according to an analysis of variance at a confidence level of 95%. Overall, this study confirms that the incorporation of RCWTB into SCC through a careful mix design is feasible in terms of flowability and compressive strength, opening a new research avenue for the recycling of wind-turbine blades as an SCC component.This research work was supported by MICIU,AEI,EU,ERDFandNextGenerationEU/PRTR [grant numbers PID2023-146642OB-I00; 10.13039/501100011033; TED2021-129715B-I00; FPU21/04364]; the Junta de Castilla y León (Regional Government) and ERDF [grant number UIC-231; BU033P23; BU066-22]; and, finally, the University of Burgos [grant number SUCONS, Y135.GI]
Revisitando «la loca en el desván»: figuraciones insólitas del espacio doméstico en ficciones contemporáneas
No full textEl capítulo analiza la relación entre género, espacio doméstico y lo fantástico en narrativa y cine contemporáneos. Comparando relatos de la española Concha Alós y de la mexicana Amparo Dávila con las películas The Babadook, de Jennifer Kent y Relic, de Natalie Erika James, ambas directoras australianas, introduce el concepto de «trans-domesticidad» para destacar el espacio doméstico como agente simbólico que refleja tensiones psicológicas y resistencias patriarcales. A través del «fantástico feminista», estas obras cuestionan las estructuras sociales tradicionales, mostrando a mujeres negociando su identidad. El enfoque interdisciplinario subraya cómo diferentes formatos y lenguas enriquecen el análisis crítico de las dinámicas de género
La actividad agraria y su configuración jurídica
No full textLa doctrina ha distinguido en el sector agrario tres elementos1: quién actúa, que es el agricultor,
normalmente empresario agrario; dónde actúa o cómo se actúa, que nos remite a la explotación agraria;
y qué hace el sujeto sobre el objeto, esto es, la actividad agraria. Es precisamente la actividad agraria
lo que configura.
Esto último es lo que sirve para configurar los otros dos aspectos: la actividad agraria se desarrolla
organizadamente en la explotación agraria, la cual es gestionada de modo eficiente por el empresario
agrario. Determinar lo que es la actividad agraria y ganadera va a permitir identificar qué operaciones
configuran a la persona como autentico agricultor o ganadero, en cual se proyecta en las denominadas
actividades complementarias, que amplían notablemente el horizonte empresarial de los agricultores.
Todo ello nos sirve de base para comprender el marco normativo de la legislación agraria, ciertamente
complejo en una nación miembro de la Unión Europea y, a la vez, dividida en comunidades autónomas
con importantes competencias asumidas en la materia
Exploring developmental changes in femoral midneck cross‐sectional properties
No full textThis research delves deeper into previous works on femoral cross-sectional properties during ontogeny by focusing for the first time on the human femoral midneck. The ontogenetic pattern of cross-sectional properties at femoral midneck is established and compared with those at three different femoral locations: the proximal femur, the midshaft, and the distal femur. The study sample includes 99 femora (70 non-adults and 29 adults) belonging to archaeological specimens. Cross-sectional properties were extracted from computed tomographic scans and analyzed with the MomentMacro plugin of ImageJ. Ontogenetic trends of these variables were assessed using locally estimated scatterplot smoothing and segmented regressions, along with Wilcoxon post hoc tests for all possible age group pairings. Our results show that the femoral midneck exhibits a unique growth pattern. Area variables showed rapid growth until adolescence, followed by a more gradual increase leading into adulthood. Nonetheless, the relative cortical area does not demonstrate any significant drops or rise during growth. The morphology of the midneck section of the femur remains stable during ontogeny, with early adolescence and the onset of adulthood marking two periods of significant change. In contrast to the femoral diaphysis, the acquisition of a mature bipedal gait does not appear to constitute a period of significant morphological change at the femoral midneck cross section.J. M. G benefits a predoctoral grant co-funded by the Government of Castilla y León and the European Union. BOCYL-D-07/07/2020 no. 135 p. 23452. The Atapuerca research project is financed by the Ministerio de Ciencia, Innovación y Universidades Grant PID2021-122355NB-C31 funded by the MCIN/AEI/10.13039/501100011033 and “ERDF A way of making Europe.
Developing an adaptive virtual learning environment for sustainable learning in individuals with Down syndrome
No full textThis study focuses on the design and technological development of a virtual learning environment tailored to
instruct students with Down Syndrome in sustainability concepts. The system grants students access to free
software designed for teaching fundamental principles related to environmental awareness, recycling, and
sustainable construction. The platform's creation is underpinned by Fogg's Persuasive Technology methodology,
emphasizing the acquisition of new competencies through technology to promote sustained engagement with
novel technology habits, thereby facilitating a seamless integration into the learning process. The study utilized a
phased approach: content adaptation, technological development, and usability evaluation. It emphasized
collaboration with stakeholders, including Down Syndrome associations and academic institutions.
Recommendations include adherence to universal design principles and further research on the platform's impact.
The platform's usability was assessed in terms of simplicity, intuitiveness, performance, robustness, and
accessibility. Observations revealed that an impressive 91.7% of students derived genuine enjoyment from the
learning tool. Feedback from both tutors and professionals indicated that 91.4% found the virtual learning
environment to be well-organized, 88.6% regarded the content as suitable and comprehensible, and nearly 80%
affirmed its utility for their professional practice.This work was supported by the co-funded by the Erasmusþ Programme of the European Union. Project “SUSKIDS” 2018-ES01-KA201-050639
Integrated Biofactory for biogas and bioproducts production, CO2 absorption and agroindustrial effluents depuration (BioTAgro)
No full textEn este documento se presenta de forma precisa la información necesaria para la operación y mantenimiento de un prototipo demostrativo de biorreactor anaerobio AnFMBR (PCT/ES2019070061) para el tratamiento de aguas residuales y producción de biogás. El documento está dividido en tres partes. La primera parte está dedicada al biorreactor, circuito de agua y de biogás, la segunda a la instalación eléctrica y, por último, la tercera presenta la filosofía de control, como se ha implementado en un PLC open-source y los comandos principales que permiten modificar las condiciones de operación del biorreactor AnFMBR.Proyecto TED2021-132393B-I00, financiado por MCIN/AEI/10.13039/501100011033 y Unión Europea ‘‘NextGenerationEU’’/PRT