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Aluminium corrosion reactivation in MKPC and Portland-based wasteforms under simulated alkaline repository conditions
No full textThe long-term stability of aluminium (Al) in cementitious wasteforms is challenged by matrix alkalinisation resulting from interaction with alkaline waters from engineered barriers in low- to intermediate-level radioactive waste (LILRW) repositories. This study evaluates the corrosion of Al (A1050) and Al-Mg (AA5754) alloys and the physicochemical evolution of magnesium potassium phosphate cement (MKPC) and Portland-based matrices (CEM I and CEM I + 50% silica fume (SF)) under simulated alkaline exposure. Over 250 days, specimens were subjected to synthetic alkaline water (SPAW), while MKPC was also embedded in a CEM I mortar (AM) to simulate repository contact conditions. In MKPC, alkaline plume diffusion from the external source triggered ion exchange with the matrix, leading to alkalinisation (pH >11), reactivation of Al corrosion, and H₂ release to levels comparable to those observed in CEM I. K-struvite dissolution, Ca–P-rich phase formation, and fly ash hydration were also observed, evidencing long-term destabilisation of the MKPC matrix. In contrast, CEM I + 50%SF, despite being exposed to a highly alkaline plume, maintained the pore solution pH at 10.7 over time due to the advanced hydration of SF, effectively limiting Al reactivity and H₂ generation without matrix alteration.The authors acknowledge funding from the European Union's Horizon 2020 Research and Innovation Programme for Nuclear Fission and Radiation Protection Research (NFRP-2019–2020 call) under Grant Agreement No. 945098 (PREDIS), as well as support from the CSIC PIE (Project No. 202260E009) and EURAD 2 (Project No. 10116671).Peer reviewe
Implications of the first CONUS+ measurement of coherent elastic neutrino-nucleus scattering
No full textV1: 27 pages, 12 figures, 2 tables, V2: Updated analysis according to
the latest data release from the CONUS+ Collaboration. Main conclusions
unchanged, V3: matches the published versionThe CONUS+ collaboration has reported their first observation of coherent
elastic neutrino-nucleus scattering (CENS). The experiment uses reactor
electron antineutrinos and germanium detectors with recoil thresholds as low as
. With an exposure of kg d, the
measurement was made with a statistical significance of . We
explore several physics implications of this observation, both within the
standard model and in the context of new physics. We focus on a determination
of the weak mixing angle, nonstandard and generalized neutrino interactions
both with heavy and light mediators, neutrino magnetic moments, and the
up-scattering of neutrinos into sterile fermions through the sterile dipole
portal and new mediators. Our results highlight the role of reactor-based
\cevns~experiments in probing a vast array of neutrino properties and new
physics models.Peer reviewe
List of captured wild pollinator species
No full textWorldwide pollinator declines are a major problem for agricultural production. However, understanding how landscape characteristics and local management influence crop production through its pollinators is still a challenge. The carob tree (Ceratonia siliqua) is a pollinator-dependent Mediterranean crop of high economic importance in food and pharmaceutical industries. To understand how crop production can be enhanced in a sustainable manner, we evaluated the effects of landscape (habitat loss) and orchard local management (farming system: conventional vs. ecological; male-to-female ratio) on pollinator communities and crop production using data on 20 carob tree orchards across Mallorca Island (Spain). We found that orchards surrounded by a greater proportion of natural landcover received more visits by wild bees and butterflies and fewer by honeybees. Overall pollinator abundance was slightly higher in ecological than conventional orchards, but the difference was not significant. High male-to-female ratio enhanced overall pollinator abundance and shaped pollinator composition, by increasing hoverfly abundance and decreasing wasp and fly abundance. Male-to-female ratio showed hump-shaped relationships with fruit and seed production per female tree (peak at 0.7 males/female), although this quadratic relationship was lost when the most male-biased orchards were removed from the analyses. Total orchard production maximized with 25-30% of males. Seed weight (farmer’s highest economic value) increased in conserved landscapes where wild pollinators prevailed, and with overall pollinator abundance; however, it decreased with male-to-female ratio, likely due to seed number-size trade-offs. Management strategies to enhance carob production may optimize sex ratios and favor wild pollinators by preserving natural landscapes.Peer reviewe
Molecular spin relaxation of f-block metal complexes for quantum applications in a nutshell
No full textПредставлено критичний огляд найновітніших досліджень одномолекулярних магнітів (SMMs) для застосування у молекулярно-спінових кубітах. Розглянуто внесок спотворень ґратки у формування бістабільного спінового стану SMMs. Проаналізовано можливості послаблення квантової декогеренції комірок памя’ті на основі SMMs через уповільнення релаксації молекулярних спінів у взаємодії з ґраткою та запобігання перетину енергетичних рівнів.Peer reviewe
Results of model-averaging from model selection of GLMMs; re-analysis excluding the study orchard with the highest male-to-female ratio and the one with mostly hermaphrodite trees
No full textResults of model-averaging from model selection of GLMMs; re-analysis excluding the study orchard with the highest male-to-female ratio and the one with mostly hermaphrodite trees.Peer reviewe
Limited knowledge of health risks along the illegal wild meat value chain in the Nairobi Metropolitan Area (NMA)
No full textConsumption of and trade in wild meat could result in infectious pathogen spillover into human populations. Such spillovers could propagate into sustained outbreaks in major cities where human aggregations potentially catalyze their spread. A better understanding of how urban wild meat value chains operate could assist in mitigating spillover events. We used key informant interviews and literature review to understand the structure and operations, actors, their practices, and health risk perceptions along a wild meat value chain supplying a rapidly urbanizing city in Africa, the Nairobi Metropolitan Area (NMA). The value chain operates via three main nodes: harvester, trader, and consumer nodes. We found wild meat to be harvested from peri-urban areas of the NMA, consumed or sold locally, or supplied to distant urban markets. Actors reported increased participation along the value chain during the dry season, and over the Christmas period. The value chain operated informally, creating a 'rules in use' framework focusing on sanction avoidance, while ignoring food safety concerns. Consequently, respondents reported slaughtering wild animals on the bare ground, handling wild meat with unwashed hands and uncleaned utensils. No value chain actors reported wearing personal protective equipment when handling wild meat. At the distant markets' trader node where wild meat was sold as livestock meat, meat vendors engaged in similar unsafe practices. Actors had limited awareness of the specific health risks from wild meat. We speculate that the observed limited health risk awareness, and sanction avoidance attempts promotes unsafe practices during exploitation of wild animals for food, income and for medicinal purposes. Multisectoral efforts at the conservation and public health nexus, as well as community education on the potential health risks from wild meat are key in reducing potential spillovers.This study was funded by the Deutsche Gesellschaft für Internationale Zusammenarbeit GmbH (GIZ) through Wageningen University and Research with additional support from the German Federal Ministry for Economic Cooperation and Development through the One Health Research, Education and Outreach Centre in Africa (OHRECA).Peer reviewe
Microwire vs. Micro-Ribbon Magnetoelastic Sensors for Vibration-Based Structural Health Monitoring of Rectangular Concrete Beams
No full textTwo different magnetoelastic Metglas materials with distinct shapes were compared as sensing elements for the structural health monitoring of concrete beams. One had a ribbon shape, while the other had a microwire shape. The sensing elements were attached to different concrete beams, and a crack was introduced into each beam. The beams were subjected to flexural vibrations, and their deformations were recorded wirelessly by coils, detecting the magnetic signals emitted due to the magnetoelastic nature of the sensors. Fast Fourier Analysis of the received signal revealed the bending mode frequencies of the beams, which serve as a “signature” of their structural health. In these spectra, the ribbon-shaped sensor exhibited a 1.4-times stronger signal than the microwire sensor. However, the extracted mode frequencies were nearly identical, with differences of less than 1% both before and after damage. This indicates that both sensors can be used equivalently to monitor structural damage in concrete beams. The damage-related relative frequency shifts ranged from −0.01 to −0.03, with similar results for both sensors. Thermal annealing was also studied and appeared to significantly enhance the signal by 10–30%, likely due to the relaxation of internal stresses induced during the rapid solidification synthesis of these materials. This enhancement was more pronounced in the ribbon-shaped sensor. This study is the first to utilize a magnetoelastic microwire sensor for damage detection in concrete beams.This research received no external funding.Peer reviewe
Evaluation of Aqueous Enzymatic Extraction for Obtaining Oil from Thevetia peruviana Seeds
No full textThe aqueous enzymatic extraction (AEE) of oil from Thevetia peruviana seeds was studied. The oil extraction yields obtained by treatment with cellulase, Alcalase, and Viscozyme L were compared, finding that the treatment with Alcalase at pH 6 and 50 °C gave the highest yield (63.07%), so it was selected for the optimization of the oil extraction process through a central composite design and a response surface methodology. An oil extraction yield of 78.22% was achieved under the optimum conditions (2% of Alcalase, 4 h of incubation, 250 rpm, and a solid-to-liquid ratio of 1:4.5). The predominant fatty acids in the oil obtained by both AEE and standard solvent extraction (SE) were oleic, linoleic, stearic, and palmitic acids. However, AEE produced an oil presenting lower acidity and peroxide values and greater oxidative stability, indicating that this method produces an oil with better quality. Scanning electron microscopy images of Thevetia peruviana seeds showed a structural alteration of their cell wall caused by AEE, which allowed the release of oil from this seed in the aqueous medium. The results suggest that AEE could be an excellent alternative in terms of efficiency, oil quality, and environmental friendliness for the extraction of this oil.Tacias-Pascacio and Castañeda-Valbuena give thanks for the financial support from “Instituto de Ciencia, Tecnología e Innovación” from the government of Chiapas, Mexico. Fernandez-Lafuente wants to thank the support from the Ministerio de Ciencia e Innovación and the Agencia Estatal de Investigación (Spanish Government) (PID2022-136535OB-I00). The authors gratefully recognize the Universidad Politécnica de Chiapas for the technical support in the scanning electron micrograph analysis. The help and suggestions from Ángel Berenguer (Departamento de Química Inorgánica, Universidad de Alicante) during the writing of this paper and the support of the engineers Ilse Vázquez-Camas and Dilan Hernández-Miguel (Tecnológico Nacional de México/Instituto Tecnológico de Tuxtla Gutiérrez) in the experimental part of the project are gratefully recognized.Peer reviewe
Microbial and Biochemical Analyses of High-Quality, Long-Ripened, Blue-Veined Cabrales Cheese
No full textSixteen long-ripened, high-quality Cabrales cheeses from independent producers underwent a comprehensive biochemical and microbiological characterisation. Significant variations in total microbial counts and specific microbial groups were observed among the cheeses. A metataxonomic analysis identified 249 prokaryotic amplicon sequence variants (ASVs) and 99 eukaryotic ASVs, respectively, which were classified into 52 prokaryotic and 43 eukaryotic species. The predominant species included bacteria of the genera Tetragenococcus, Lactococcus (of which Lactococcus lactis was used as a starter), and Staphylococcus, followed by Brevibacterium and Corynebacterium species. The starter mould Penicillium roqueforti was highly abundant in all cheeses; Debaryomyces hansenii, Geotrichum candidum, and Kluyveromyces spp. constituted the subdominant fungal populations. Glutamic acid (≈20 mg g−1) was the most abundant free amino acid in all samples, followed by lysine, leucine, and valine (≈10–13 mg g−1). Moderate-to-high amounts of the biogenic amines tyramine and ornithine were detected. A large variation between cheeses of the main organic acids (lactic, acetic, or butyric) was detected. Differences between samples were also observed for the majority volatile compounds, which included organic acids, alcohols, esters, and ketones. Positive and negative correlations between bacterial and fungal species were detected, as well as between microbial populations and key biochemical markers. Among the latter, Tetragenococcus halophilus correlated positively with ethyl caprylate and hexanoic acid, and Loigolactobacillus rennini correlated positively with γ-aminobutyric acid. Conversely, Staphylococcus equorum showed a strong negative correlation with ethyl caprylate and capric acid. These microbial and biochemical insights enabled us to propose a microbiota-based starter culture comprising prokaryotic and eukaryotic components to enhance Cabrales cheese quality.The work was supported by a research grant (ref. PID2022-141271NB-I00) funded by MCIN/AEI/10.13039/501100011033 and by the “ERDF A way of making Europe” project and Asturias Principality (IDE/2024/00073650916). L.V. was awarded a postdoctoral research contract from the Health Research Institute of Asturias Principality (ISPA-FINBA). A Ph.D. grant of the Severo Ochoa Program from Asturias Principality was awarded to J.R. (BP19-098).Peer reviewe
Effect of Use of Alkaline Waste Materials as a CO2 Sink on the Physical and Mechanical Performance of Eco-Blended Cement Mortars—Comparative Study
No full textThis research paper provides new insights into the impact of accelerated mineralization of alkaline waste materials on the physical and mechanical behavior of low-carbon cement-based mortars. Standardized eco-cement mortars were prepared by replacing Portland cement with 7% and 20% proportions of three alkaline waste materials (white ladle furnace slag, biomass ash, and fine concrete waste fraction) that had been previously carbonated in a static reactor at predefined humidity and CO2 concentration. The mortars’ physical (total/capillary water absorption, electrical resistivity) and mechanical properties (compressive strength up to 90 d of curing) were analyzed, and their microstructures were examined using mercury intrusion porosimetry and computed tomography. The results reveal that carbonated waste materials generate a greater heat of hydration and have a lower total and capillary water absorption capacity, while the electrical resistivity and compressive strength tests generally indicate that they behave similarly to mortars not containing carbonated minerals. Mercury intrusion porosimetry (microporosity) indicates an increase in total porosity, with no clear refinement versus non-carbonated materials, while computed tomography (macroporosity) reveals a refinement of the pore structure with a significant reduction in the number of larger pores (>0.09 mm3) and intermediate pores (0.001–0.09 mm3) when carbonated residues are incorporated that varies depending on waste material. The construction and demolition waste (CCDW-C) introduced the best physical and mechanical behavior. These studies confirm the possibility of recycling carbonated waste materials as low-carbon supplementary cementitious materials (SCMs).The authors are thankful to the Ministry of Science, Technological Development and Innovation of the Republic of Serbia (Contract number 451-03-136/2025-03/200012).Peer reviewe