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Scrutinizing the sharp magnetoelastic transition and kinetic arrest in Fe49Rh51 alloy using neutron thermo-diffraction
No full textThis article is part of the themed collection: Journal of Materials Chemistry C HOT Papers.The Fe49Rh51 bulk alloy undergoes a sharp first-order magnetostructural transition from the antiferromagnetic (AFM) to ferromagnetic (FM) state around 332 K, accompanied by a drastic change of around 0.8% in the unit cell volume. Neutron thermo-diffraction experiments have been carried out to investigate the concomitant coupling between spin and lattice degrees of freedom in detail. Although it seems that the alloy entirely changes from the AFM to FM order in a very narrow temperature range (with a hysteresis of about 6 K), evidence of AFM order persists even 70 K above the first-order phase transition, suggesting a kinetic arrest of the AFM phase during both heating and cooling procedures. The estimated value for the Fe magnetic moment in the AFM phase at room temperature, around μFe ≈ 3.4μB, agrees with those already reported and reaches 3.8μB at T = 10 K. However, in the FM phase, μFe decreases to ≈ 2.3μB, while Rh acquires a magnetic moment of around 0.9μB. The use of temperature first-order reverse curves of neutron thermo-diffraction gives additional information about the magnetostructural coupling within the transition. Time-resolved neutron diffraction patterns collected at selected temperatures show that the alloy fully relaxes above the transition temperature, with both the magnetic and structural transformations occurring at the same temperature and with similar relaxation times.This work has been partially supported by the following projects: (a) PTDC/EMETED/3099/2020, UIDP/04968/2020-Programatico; (b) PID2022-138256NB-C21, from Spanish MCIN/AEI/10.13039/501100011033 and ERDF, UE; (c) CF-2023-I-2143 from CONAHCYT, Mexico; and (d) SEK-25-GRU-GIC-24-113 from SEKUENS Agency of the Principality of Asturias. K. Padrón-Alemán acknowledges the Institute Laue-Langevin for his PhD/CFR contract (Reference: ESP-5-2023). M.L. Arreguín-Hernandez thanks DGAPA-UNAM and CONAHCYT for supporting her postdoctoral position at UNAM and PhD studies at IPICyT (scholarship 861515; 2023–2020). The authors acknowledge Institute Laue-Langevin for the beam-time allocations 5-31-2945 and 5-25-290 and the Spanish Initiatives on Neutron Scattering (SPINS) for the beam-time allocation CRG-3054.Peer reviewe
Adsorption of benzophenone-3 and octocrylene UV filters on polyethylene: analysis by HPLC-MS/MS and voltammetry with screen-printed electrodes
No full textMicroplastics (MPs) are persistent pollutants that can adsorb contaminants, facilitating their accumulation in aquatic ecosystems. The presence of UV filters (UVFs) such as benzophenone-3 (BP3) and octocrylene (OC), exacerbates this issue, particularly in coastal areas. This study presents an innovative dual-method approach combining high-performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS) and differential pulse adsorptive stripping voltammetry (DPAdSV) to assess the adsorption of UVFs on polyethylene (PE), a widely found polymer in aquatic environments. Adsorption kinetics were analysed using pseudo-first-order (PFOM) and pseudo-second-order (PSOM) models, revealing a higher equilibrium sorption capacity for OC due to its stronger hydrophobic interactions with PE. A central composite design (CCD) was employed to enhance resources efficiency in experimentation and controlled experiments exposed the materials to both pure fresh water and synthetic seawater. The results indicate a higher adsorption affinity of OC on PE than BP3, attributed to its high octanol-water partition coefficient (log Kow 6.88) and stronger hydrophobic interactions. Exposure time was the most influential variable across both media, while pH and temperature had a significant effect on BP3 adsorption in synthetic seawater. Hydrophobic partitioning, aided by van der Waals forces, was identified as the dominant interaction mechanism for both UVFs, with π-π and electrostatic interactions playing minimal roles due to the nature of the polymer. The study provides new insights into how polymer-pollutant interactions vary across environmental conditions and offers a novel voltammetric alternative for in-situ UVFs monitoring.The authors acknowledge the financial support of the Generalitat de Catalunya (projects 2021 SGR 00753 and 2021 SGR 00006), the Spanish State Research Agency (AEI) through project PID2022-136709OB-C22, co-funded by the European Union NextGenerationEU/PRTR, and the Ministry of Science, Innovation, and Universities through project PID2023-151815OB-I00.Peer reviewe
Interlibrary cooperation of the CSIC’s Libary and Archive Network, some examples
No full textEn directo.-- Colaboración para avanzar. Mario Cottereau. URICI-CSIC (Madrid).[ES] Se presentan algunas de las colaboraciones más importantes que mantiene la Red de Bibliotecas y Archivos del CSIC en España y varios ejemplos con entidades extranjeras.[EN] Some of the most important collaborations established by CSIC’s Library and Archive Network in Spain are presented, along with some examples with foreign institutions.Peer reviewe
Age- and sex-specific reference percentile curves for accelerometry-measured physical activity in healthy European children and adolescents
No full textHELENA study group: et al.Physical activity measured by accelerometry (PA-accelerometry) is used as an indicator of physical capacity in chronic diseases. Currently, only fragmented age ranges of reference percentile curves are available for European children and adolescents. This study aimed to provide age- and sex-specific percentiles for physical activity measured by hip-worn accelerometry derived throughout the full age range of European children and adolescents. Individual-level population-based PA data measured by accelerometry from HELENA and IDEFICS/I.Family studies were pooled and harmonized. Together these studies involved children and adolescents aged 2–18 years from 12 European countries. Primary outcomes included averaged counts per minute (CPM), sedentary time (SED), light PA (LPA) and moderate-to-vigorous PA (MVPA). Generalized Additive Models for Location, Scale and Shape were used to derive age- and sex-specific reference percentile curves for these outcomes. The combined cohort consisted of 11,645 children and adolescents aged 2 to 18 years who contributed 14,610 valid accelerometry recordings, with a median accelerometer wear time of 6 days. This dataset allowed for the construction of age- and sex-specific reference percentile curves for CPM, SED, LPA, and MVPA. The curves demonstrated varying trends and variability across age groups.[Conclusions]: This study provides age- and sex-specific percentile curves for PA-accelerometry in European children and adolescents, addressing a current gap in the availability of full-age range reference data. These curves based on healthy children and adolescents can be used by clinicians, researchers, and policymakers to interpret PA-accelerometry measurements, track physical activity trends, and evaluate treatment responses and health interventions.This work was supported by the European Commission within the Sixth RTD Framework Programme for the HELENA study (Contract No. 007034), for the IDEFICS study (Contract No. 016181) and within the Seventh RTD Framework Programme for the I.Family Study (contract no. 266044).Peer reviewe
Engineering xylose isomerase and reductase pathways in Yarrowia lipolytica for efficient lipid production
No full text13 p.-5 fig.-3 tab.Xylose is a common monosaccharide in lignocellulosic residues that Yarrowia lipolytica cannot naturally metabolise for lipid production and therefore, heterologous xylose metabolic pathways must be engineered in this yeast to facilitate its consumption. We have compared the metabolic efficiency of two xylose metabolic pathways by developing three recombinant Y. lipolytica strains: one harbouring a xylose reductase pathway, one with a xylose isomerase pathway, and one combining both pathways, and the strains were tested for xylose consumption and lipid production at different scales. The recombinant strain with the reductase pathway that was directly isolated in selective xylose medium showed the highest lipid yield, producing up to 12.8 g/L of lipids, or 43% of the biomass dry weight, without requiring any other xylose consumption adaptive evolution process. This strain achieved a lipid yield of 0.13 g lipids/g xylose, one of the highest yields in yeast reported so far using xylose as the sole carbon and energy source. Although the strain harbouring the isomerase pathway performed better under oxygen-limiting conditions and led to higher lipid intracellular accumulation, it showed a lower xylose uptake and biomass production, rendering a lower yield under non-limiting oxygen conditions. Unexpectedly, the combination of both pathways in the same strain was less effective than the use of the reductase pathway alone.This research was conducted within the scope of the European project FRONTSH1P, receiving financial support from the European Union's Horizon 2020 research and innovation programme under grant agreement no. 101037031.Peer reviewe
An acoustic levitator design for suspending cosmic dust analogues and aerosol particles in light scattering experiments
No full textWe present a design of an acoustic levitator composed of 35 ultrasonic transducers operating at 40 kHz configured to form a spherical cavity. The acoustic radiation force measured experimentally in the center of the cavity is Frad≈9.6mN, enough for levitating spheres as well as irregular particles of different materials of up to ~ 50 mg. Levitation tests have been performed with particles of different geometries and compositions, including liquid droplets and minerals relevant in studies of atmospheric aerosol and cosmic dust. This device has been deployed in the center of a polar nephelometer set-up to conduct studies of light scattering by irregular solid particles and liquid droplets. Test experiments have been carried out using a 1.5 mm diameter NBK- 7 glass sphere, for which three elements of the scattering matrix have been measured as functions of the scattering angle using a 647 nm diode laser. Mie theory calculations of the scattering matrix elements at this wavelength agree well with the measurements, demonstrating the functionality of the whole device. © The Author(s) 2025This work has been funded by PID2021 - 123370OB- 100/AEI/https://doi.org/
10.13039/501100011033/FEDER and Severo Ochoa grant CEX2021 - 001131-S funded by MCIN/
AEI/https://doi.org/10.13039/501100011033.Peer reviewe
#TodasHacemosCiencia. Women’s verses
No full textNoticias.-- Miriam Font Ugalde, Concha de la Torre de Benito. EEA-CSIC (Granada).Con motivo de las celebraciones del Día Internacional de la Mujer y la Niña en la Ciencia (11 de febrero) y del Día Internacional de la Mujer (8 de marzo) de 2024, la biblioteca de la Escuela de Estudios Árabes dedicó su muestra “Lecturas escogidas” a las poetisas de al-Andalus, mujeres de origen social diverso y en su gran mayoría cultas, que estaban muy bien consideradas por los hombres de su entorno y utilizaban sus versos como vehículo de expresión y comunicación social.Peer reviewe
A new Mediterranean lifestyle pyramid for children and youth: A critical lifestyle tool for preventing obesity and associated cardiometabolic diseases in a sustainable context
No full textR. Casas et al.Cardiovascular disease risk factors begin in childhood and track into adulthood, increasing the possibility of impaired cardiometabolic health. Adopting healthy dietary patterns can help curb childhood obesity, a worrisome epidemic problem at present. In the era of personalized nutrition, dietary recommendations should be adapted to different stages of life, including children (older than 3 y) and adolescents. In this study, we present an updated version of the Mediterranean Lifestyle Pyramid addressed to children and adolescents, which may be used as a prevention tool by health professionals, teachers, and stakeholders. This pyramid arises from a consensus position between participants in an International Congress on Mediterranean diet held in Barcelona. During this meeting, after reviewing all literature published, a consensus was reached on the new Mediterranean Lifestyle Pyramid for kids including details such as labels of the pyramid, position of foods, servings, type of foods, and healthy lifestyle habits. All components of the pyramid are supported by the most recent scientifically sound research and are based upon top-level evidence in nutritional sciences. Fruit, vegetables, legumes, nuts, wholegrains, and extra-virgin olive oil continue to be at the basis of the pyramid, but the importance of an adequate intake of fish, dairy products, and meat during these particular ages, when body and brain development occurs, is also considered. The promotion of physical activity, adequate sleep, and good emotional health are emphasized, as well as the consumption of seasonal and local products, and overall sustainability. Improving dietary habits in early stages of life should increase health in adulthood and reduce future incidence of noncommunicable chronic diseases. The Mediterranean diet and its graphic representation in the Lifestyle Pyramid should be a health-fostering tool not only for adults and children but also for the entire planet because it promotes the diversity of species, respect for the earth, and the local economy.Peer reviewe
Modeling the global shape and surface morphology of the Ryugu asteroid using an improved neural implicit method
No full textContext. Detailed shape modeling is a fundamental task in the context of small body exploration aimed at supporting scientific research and mission operations. The neural implicit method (NIM) is a novel deep learning technique that models the shapes of small bodies from multi-view optical images. While it is able to generate models from a small set of images, it encounters challenges in accurately reconstructing small-scale or irregularly shaped boulders on Ryugu, which hinders the investigation of detailed surface morphology.Aims. Our goal is to accurately reconstruct a high-resolution shape model with refined terrain details of Ryugu based on a limited number of images.Methods. We propose an improved NIM that leverages multi-scale deformable grids to flexibly represent the complex geometric structures of various boulders. To enhance the surface accuracy, three-dimensional (3D) points derived from the Structure-from-Motion plus Multi-View Stereo (SfM-MVS) method were incorporated to provide explicit supervision during network training. We selected 131 Optical Navigation Camera Telescope images from two different mission phases at different spatial resolutions to reconstruct two Ryugu shape models for performance evaluation.Results. The proposed method effectively addresses the challenges encountered by NIM and demonstrates an accurate reconstruction of high-resolution shape models of Ryugu. The volume and surface area of our NIM models are closely aligned with those of the prior shape model derived from the SfM-MVS method. However, despite utilizing fewer images, the proposed method achieves a higher resolution and refinement performance in polar regions and for irregularly shaped boulders, compared to the SfM-MVS model. The effectiveness of the method applied to Ryugu suggests that it holds significant potential for applications to other small bodies. © The Authors 2025Part of this work was supported by the China Scholarship Council (CSC) under Grants 202006260004. This research was supported by the International Space Science Institute (ISSI) in Bern and Beijing, through ISSI/ISSI-BJ International Team project ‘Timing and Processes of Planetesimal Formation and Evolution’ (ISSI Team project #561; ISSI-BJ Team project #54).Peer reviewe
Are CMB derived cosmological parameters affected by foregrounds associated to nearby galaxies
No full textWe perform cosmological parameters estimation on Planck cosmic microwave background (CMB) maps masking the recently discovered foreground related to nearby spiral galaxies. In addition, we also analyze the association between these foreground regions and recent claims of cosmological causal horizons in localized CMB parameter estimates. Our analysis shows consistent cosmological parameter values regardless of the masking approach, though reduced sky areas introduce larger uncertainties. By modeling the new extragalactic foreground, we identify a resemblance with local parameter variation maps with a statistical significance at the 3σ level, suggesting that a simplified foreground model partially accounts, (40-50)% correlation with 15% uncertainty, for the observed causal horizons. These findings add new evidence to the existence of the new foreground associated with large spiral galaxies and show that estimates of cosmological parameters on smaller patches on the sky can be largely affected by these foregrounds, but that the parameters taken over the full sky are unaltered.This work was partially supported by Agencia Nacional de Promoción Científica y Tecnológica (No. PICT 2015-3098, No. PICT 2016-1975), the Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET, Argentina) and the Secretaría de Ciencia y Tecnología de la Universidad Nacional de Córdoba (SeCyT-UNC, Argentina). Results in this paper are based on observations obtained with Planck [34], an European Space Agency (ESA) science mission with instruments and contributions directly funded by ESA Member States, NASA, and Canada. The simulations were performed on resources provided by UNINETT Sigma2—the National Infrastructure for High Performance Computing and Data Storage in Norway.” Some of the results in this paper have been derived using the healpix package [35]. This work used computational resources from CCAD—Universidad Nacional de Córdoba [36], which are part of SNCAD—MinCyT, República ArgentinaPeer reviewe