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In this work we present a computational study of alkaline earth oxides (001) surfaces interfaced with water by means of density functional theory (DFT) in conjunction with ab initio molecular dynamics (AIMD) calculations. We studied the nature of MgO, CaO, SrO, and BaO (001) surfaces in contact with water. Results show that water dissociation is promoted as the alkaline earth metal becomes heavier. Similarly, the coordination number of the cation atoms with water molecules follows the same trend, indicating a more favorable interaction. The combined analysis of rumpling and pair distribution functions allows to provide a correspondence between reactivity of atoms on the surface and capability to coordinate water molecules. Except for MgO, the remaining surfaces display strong structural changes upon hydration, a relevant message when modelling hydrated surfaces. We also investigated the effect of the water thickness by adsorbing a water monolayer and bilayer to the surface. The findings of the study and the adopted approach could be of help for future studies of more complex systems or to provide fundamental rationalizations.

Opinion statementPSMA-PET has been a practice-changing imaging biomarker for the management of men with PCa. Research suggests improved accuracy over conventional imaging and other PET radiotracers in many contexts. With multiple approved PSMA-targeting radiotracers, PSMA PET will become even more available in clinical practice. Its increased use requires an understanding of the prospective data available and caution when extrapolating from prior trial data that utilized other imaging modalities. Future trials leveraging PSMA PET for treatment optimization and management decision-making will ultimately drive its clinical utility.

A variety of scattering-based, microscopy-based, and mobility-based methods are frequently used to probe the size distributions of colloidal nanoparticles with transmission electron microscopy (TEM) often considered to be the "gold standard". Charge detection mass spectrometry (CDMS) is an alternative method for nanoparticle characterization that can rapidly measure the mass and charge of individual nanoparticle ions with high accuracy. Two low polydispersity, ∼100 nm diameter nanoparticle size standards with different compositions (polymethyl methacrylate/polystyrene copolymer and 100% polystyrene) were characterized using both TEM and CDMS to explore the merits and complementary aspects of both methods. Mass and diameter distributions are rapidly obtained from CDMS measurements of thousands of individual ions of known spherical shape, requiring less time than TEM sample preparation and image analysis. TEM image-to-image variations resulted in a ∼1-2 nm range in the determined mean diameters whereas the CDMS mass precision of ∼1% in these experiments leads to a diameter uncertainty of just 0.3 nm. For the 100% polystyrene nanoparticles with known density, the CDMS and TEM particle diameter distributions were in excellent agreement. For the copolymer nanoparticles with unknown density, the diameter from TEM measurements combined with the mass from CDMS measurements enabled an accurate measurement of nanoparticle density. Differing extents of charging for the two nanoparticle standards measured by CDMS show that charging is sensitive to nanoparticle surface properties. A mixture of the two samples was separated based on their different extents of charging despite having overlapping mass distributions centered at 341.5 and 331.0 MDa.

Glabridin is an antimicrobial compound which can be extracted from plants, such as liquorice (Glycyrrhiza glabra) roots. Although its activity against foodborne pathogens and spoilage microorganisms has already been reported, the investigation of potential applications as a surface disinfectant is still largely unexplored. Hence, this study evaluated the disinfectant efficacy of glabridin against Listeria monocytogenes. The activity of glabridin was first tested in vitro in a nutrient-rich medium against eight strains of L. monocytogenes, including food isolates and the model strain EGDe. The tested strains showed similar susceptibility with minimal inhibitory and bactericidal concentrations of 12.5 µg/mL and 25 µg/mL, respectively. Subsequently, L. monocytogenes L6, FBR17 and EGDe were selected to assess the efficacy of glabridin against dried cells (according to the European standard EN 13697:2015 + A1:2019) and biofilm cells on stainless steel surfaces. Moreover, the impact of food residual organic matter was investigated using skim milk, cantaloupe and smoked salmon solution as soiling components. Our results showed that applying 200 µg/mL of glabridin resulted in a substantial reduction (>3 log10) of dried and biofilm cells of L. monocytogenes in standard conditions (i.e. low level of residual organic matter). Cantaloupe soiling components slightly reduced the activity of glabridin, while the efficacy of glabridin when tested with salmon and skim milk residuals was substantially affected. Comparative analysis using standardized protein contents provided evidence that the type of food matrices and type of proteins may impact the activity of glabridin as a disinfectant. Overall, this study showed low strain variability for the activity of glabridin against L. monocytogenes and shed light on the possible application of this natural antimicrobial compound as a surface disinfectant.

Here the synthesis of magnetic aerogels from iron platinum and cobalt platinum nanoparticles is presented. The use of hydrazine monohydrate as destabilizing agent triggers the gelation directly from organic solution, and therefore a phase transfer to aqueous media prior to the gelation is not necessary. The aerogels were characterized through Transmission Electron Microscopy, Scanning Electron Microscopy, Powder X-Ray Diffraction Analysis and Argon Physisorption measurements to prove the formation of a porous network and define their compositions. Additionally, magnetization measurements in terms of hysteresis cycles at 5 K and 300 K (M-H-curves) as well as zero field cooled-field cooled measurements (ZFC-FC measurements) of the dried colloids and the respective xero- and aerogels were performed, in order to analyze the influence of the gelation process and the network structure on the magnetic properties.

Examensarbetets syfte är att undersöka vilka skillnader i skyddsnivå som brandskyddsfärg ger vidbrandexponering beroende på underliggande träpanels tidigare ytbehandling. Genom två separata försöksuppställningar kunde det uttydas att om en träpanel sedan tidigare ärytbehandlad kan det påverka brandskyddsfärgens förmåga att skydda mot brand. Dessa tvåförsökuppställningar visade att den studerade brandskyddsfärgen ger bäst brandskyddsförmåga om denappliceras likt fabrikatörens anvisningar, alltså på en obehandlad träyta. Arbetet visade dock att träpanelerna behandlade med brandskyddsfärg på akrylatfärg enbart visade en relativt liten försämringvid jämförelser med träpanelen utförd enligt fabrikatörens anvisning för de utförda experimenten. Större skillnader kunde påvisas då prov behandlat med linoljefärg gav större försämringar ibrandskyddsfärgens förmåga att motverka pyrolys i det underliggande trämaterialet. Resultaten indikerat att även om man har en underliggande ytbehandling så motverkarbrandskyddsfärgen antändning, fortskridande brandspridning längs med träytan, rökproduktion och effektutvecklingen efter antändning., The purpose of this thesis is to identify the differences in protection that the intumescent paint provides in relation to fire, depending on prior surface finishes.Through two separate experimental setups, it was deduced that if a wood panel has undergone prior surface treatment, it can have a significant impact on the intumescent paint's ability to protect against fire. These two experimental setups demonstrated that the intumescent paint exhibits the best fireprotection capability when applied according to the manufacturer's instructions, i.e., on an untreatedwood surface. However, the results revealed that wood panels treated with fire protection paint overacrylic paint only showed a relatively small deterioration compared to the panel treated according tothe manufacturer's instructions for the performed experiments. However, substantial differences emerged in the efficiency of the intumescent paint when panels treated with linseed oil paint where tested.The results indicate that even if the substrate is treated with a surface treatment, intumescent paint willstill provide a safety-enhancing effect.

The spin degree of freedom in magnetically ordered materials is an important aspect for a variety of research directions. Antiferromagnets represent a broad class of systems with compensated or almost compensated net magnetization. On one side, it is a factor in the complications of their experimental investigation. However, on the other side, they offer unique features on ultrafast dynamics, strong robustness regarding external magnetic fields and delicate symmetry-driven phenomena in spin torques and multiferroicity. Specific research attention is paid to the properties of antiferromagnetic solitons as potential information carriers and the surface properties at which the readout of the magnetic state is performed. Here, we focus on the seminal magnetoelectric antiferromagnet Cr2O3 (chromia) with the easy-axis magnetic anisotropy. In bulk single crystal chromia, the multidomain state is not favorable due to thermodynamic reasons, thus the stabilization of domain walls is possible on the defects. In particular, the litographically partterned surface topography of the sample can serve as the pinning landscape for the domain wall. The spatial inhomogeneity of this landscape allows to uncover the mechanical properties of the magnetic textures such as elastic deformation of the domain wall plane governed by the exchange boundary conditions [1]. In contrast, the chromia thin films are commonly in the multidomain state, which is determined by their granular structure. The domain wall pinning at the defects depends on the defect properties. Therefore, the visual analysis of the domain picture obtained, e.g., via Nitrogen vacancy magnetometry can be used as a source of quantification of the inter-grain coupling in the thin film [2]. Furthermore, in the case of the high-quality chromia samples epitaxially grown at sapphire substrate, the presence of domain walls allows to reveal a new temperature-driven source of the flexomagnetism in thin antiferromagnetic films [3]. Even

Abundant coal reserves make this material a substitute fuel choice, especially for industry. The use of coal carries a high risk due to incomplete combustion and produces fly ash products. Fly ash cause pollution and health risks as well as environmental contamination when they are released, deposited, or leached into the ecosystem over short or long periods of time. The high content of silica and alumina in fly ash can be utilized and modified into new materials with added value. This research aims to modify the surface of fly ash using stearic acid as a hydrophobic inorganic material. Fly ash from Asam-asam Coal Power Plant was characterized by using XRD and modified by immersing in stearic acid (2,4,6, and 8%) and 98% ethanol. The result showed that the contact angle increases when fly ash is modified on the surface using stearic acid. The contact angle increases with increasing stearic acid concentration. The highest contact angle was obtained at a stearic acid concentration of 8%, and the lowest at 2% was about 112.9 and 102.2, respectively. The fly ash composition was primarily silica and alumina, which were crystalline, as confirmed by XRD. These findings provide several aspects of fly ash and its potential as a candidate material for environmental remediation and waste management.

Examensarbetets syfte är att undersöka vilka skillnader i skyddsnivå som brandskyddsfärg ger vidbrandexponering beroende på underliggande träpanels tidigare ytbehandling. Genom två separata försöksuppställningar kunde det uttydas att om en träpanel sedan tidigare ärytbehandlad kan det påverka brandskyddsfärgens förmåga att skydda mot brand. Dessa tvåförsökuppställningar visade att den studerade brandskyddsfärgen ger bäst brandskyddsförmåga om denappliceras likt fabrikatörens anvisningar, alltså på en obehandlad träyta. Arbetet visade dock att träpanelerna behandlade med brandskyddsfärg på akrylatfärg enbart visade en relativt liten försämringvid jämförelser med träpanelen utförd enligt fabrikatörens anvisning för de utförda experimenten. Större skillnader kunde påvisas då prov behandlat med linoljefärg gav större försämringar ibrandskyddsfärgens förmåga att motverka pyrolys i det underliggande trämaterialet. Resultaten indikerat att även om man har en underliggande ytbehandling så motverkarbrandskyddsfärgen antändning, fortskridande brandspridning längs med träytan, rökproduktion och effektutvecklingen efter antändning., The purpose of this thesis is to identify the differences in protection that the intumescent paint provides in relation to fire, depending on prior surface finishes.Through two separate experimental setups, it was deduced that if a wood panel has undergone prior surface treatment, it can have a significant impact on the intumescent paint's ability to protect against fire. These two experimental setups demonstrated that the intumescent paint exhibits the best fireprotection capability when applied according to the manufacturer's instructions, i.e., on an untreatedwood surface. However, the results revealed that wood panels treated with fire protection paint overacrylic paint only showed a relatively small deterioration compared to the panel treated according tothe manufacturer's instructions for the performed experiments. However, substantial differences emerged in the efficiency of the intumescent paint when panels treated with linseed oil paint where tested.The results indicate that even if the substrate is treated with a surface treatment, intumescent paint willstill provide a safety-enhancing effect.

Abundant coal reserves make this material a substitute fuel choice, especially for industry. The use of coal carries a high risk due to incomplete combustion and produces fly ash products. Fly ash cause pollution and health risks as well as environmental contamination when they are released, deposited, or leached into the ecosystem over short or long periods of time. The high content of silica and alumina in fly ash can be utilized and modified into new materials with added value. This research aims to modify the surface of fly ash using stearic acid as a hydrophobic inorganic material. Fly ash from Asam-asam Coal Power Plant was characterized by using XRD and modified by immersing in stearic acid (2,4,6, and 8%) and 98% ethanol. The result showed that the contact angle increases when fly ash is modified on the surface using stearic acid. The contact angle increases with increasing stearic acid concentration. The highest contact angle was obtained at a stearic acid concentration of 8%, and the lowest at 2% was about 112.9 and 102.2, respectively. The fly ash composition was primarily silica and alumina, which were crystalline, as confirmed by XRD. These findings provide several aspects of fly ash and its potential as a candidate material for environmental remediation and waste management.

Despite advancements in cancer immunotherapy, solid tumors remain formidable challenges. In glioma, profound inter- and intra-tumoral heterogeneity of antigen landscape hampers therapeutic development. Therefore, it is critical to consider alternative sources to expand the repertoire of targetable (neo-)antigens and improve therapeutic outcomes. Accumulating evidence suggests that tumor-specific alternative splicing (AS) could be an untapped reservoir of antigens. In this study, we investigated tumor-specific AS events in glioma, focusing on those predicted to generate major histocompatibility complex (MHC)-presentation-independent, cell-surface antigens that could be targeted by antibodies and chimeric antigen receptor-T cells. We systematically analyzed bulk RNA-sequencing datasets comparing 429 tumor samples (from The Cancer Genome Atlas) and 9166 normal tissue samples (from the Genotype-Tissue Expression project), and identified 13 AS events in 7 genes predicted to be expressed in more than 10% of the patients, including PTPRZ1 and BCAN, which were corroborated by an external RNA-sequencing dataset. Subsequently, we validated our predictions and elucidated the complexity of the isoforms using full-length transcript amplicon sequencing on patient-derived glioblastoma cells. However, analyses of the RNA-sequencing datasets of spatially mapped and longitudinally collected clinical tumor samples unveiled remarkable spatiotemporal heterogeneity of the candidate AS events. Furthermore, proteomics analysis did not reveal any peptide spectra matching the putative antigens. Our investigation illustrated the diverse characteristics of the tumor-specific AS events and the challenges of antigen exploration due to their notable spatiotemporal heterogeneity and elusive nature at the protein levels. Redirecting future efforts toward intracellular, MHC-presented antigens could offer a more viable avenue.

In the article, experimental studies were carried out with the aim of determining the influence of different modes of vibro-impact cutting modes of optical slugs on the roughness of obtained surfaces. From the results obtained during the measurements and their mathematical processing are evaluated the average sizes and intervals and the parameters of the roughness of treated surfaces.

The magnetoresistance of La0.7Sr0.3MnO3/SrTiO3 superlattices with magnetic field rotating out-of-plane shows unexpected peaks for in-plane fields. Resistivity calculations with spin–orbit coupling reveal that orbital reconstruction at the manganite interface leads to a 2D ferromagnetic electron gas coupled antiparallel to the manganite “bulk”. These orbital and magnetic reconstructions are supported by X-ray linear dichroism and ab initio calculations., Ministerio de Economía y Competitividad (España), Depto. de Física de Materiales, Fac. de Ciencias Físicas, TRUE, pub

2023 Otros acuerdos transformativos de la UCM, Oxide-based 2D electron gases (2DEGs) have generated significant interest due to their potential for discovering novel physical properties. Among these, 2DEGs formed in KTaO_3 stand out due to the recently discovered crystal face-dependent superconductivity and large Rashba splitting, both of which hold potential for future oxide electronics devices. In this work, angle-resolved photoemission spectroscopy is used to study the electronic structure of the 2DEG formed at the (110) surface of KTaO_3 after deposition of a thin Al layer. The experiments reveal a remarkable anisotropy in the orbital character of the electron-like dispersive bands, which form a Fermi surface consisting of two elliptical contours with their major axes perpendicular to each other. The measured electronic structure is used to constrain the modeling parameters of self-consistent tight-binding slab calculations of the band structure. In these calculations, an anisotropic Rashba splitting is found with a value as large as 4 meV at the Fermi level along the [−110] crystallographic direction. This large unconventional and anisotropic Rashba splitting is rationalized based on the orbital angular momentum formulation. These findings provide insights into the interpretation of spin-orbitronics experiments and help to constrain models for superconductivity in the KTO(110)-2DEG system., Comunidad de Madrid, Ministerio de Ciencia e Innovación (España), Agencia Estatal de Investigación (España), Fondo Europeo de Desarrollo Regional (Unión Europea), Depto. de Física de Materiales, Fac. de Ciencias Físicas, TRUE, pub

Antiferromagnets are normally thought of as materials with compensated magnetic sublattices. This adds to their technological advantages but complicates readout of the antiferromagnetic state. We demonstrate theoretically the existence of a Dzyaloshinskii--Moriya interaction (DMI) which is determined by the magnetic symmetry classes of \ch{Cr2O3} surfaces with an in-plane magnetic easy axis. The DMI explains a previously predicted out-of-plane magnetization at the nominally compensated surfaces of chromia, leading to a surface-localized canted ferrimagnetism. This is in agreement with magnetotransport measurements and with density functional theory predictions which further allow us to quantify the strength of DMI. The temperature dependence of the transversal resistance for these planes shows distinct behavior in comparison with that of the \ch{Cr2O3} $c$~plane, which we attribute to the influence of DMI. Our work provides a framework to analyze surface-driven phenomena in antiferromagnets, and motivates the use of nominally compensated chromia surfaces for antiferomagnetic spintronics and magnonics.

Focused beams of electrons, which act as both sources and sensors of electric fields, can be used to characterize the electric response of complex photonic systems by locally probing the induced optical near fields. This functionality can be complemented by embracing the recently developed vortex electron beams (VEBs), made up of electrons with orbital angular momentum, which could, in addition, probe induced magnetic near fields. In this work we revisit the theoretical description of this technique, dubbed vortex electron energy-loss spectroscopy (v-EELS). We map the fundamental, quantum-mechanical picture of the scattering of the VEB electrons to the intuitive classical models, which treat the electron beams as a superposition of linear electric and magnetic currents. We then apply this formalism to characterize the optical response of dielectric nanoantennas with v-EELS. Our calculations reveal that VEB electrons probe electric or magnetic modes with different efficiency, which can be adjusted by changing either beam vorticity or acceleration voltage to determine the nature of the probed excitations. We also study a chirally arranged nanostructure, which in the interaction with electron vortices produces dichroism in electron-energy-loss spectra. Our theoretical work establishes VEBs as versatile probes that could provide information on optical excitations otherwise inaccessible with conventional electron beams.

We study theoretically and experimentally the process of Brillouin light scattering on an array of silicon disks on a thin Permalloy layer. We show that phase-resolved Brillouin light scattering microscopy performed on an array of weakly interacting dielectric nanoresonators can detect nanoscale waves and measure their dispersion. In our experiment, we were able to map the evolution of the phase of the spin wave with a wavelength of 209 nm with a precision of 6 nm. These results demonstrate the feasibility of all-optical phase-resolved characterization of nanoscale spin waves.

Focused beams of electrons, which act as both sources and sensors of electric fields, can be used to characterize the electric response of complex photonic systems by locally probing the induced optical near fields. This functionality can be complemented by embracing the recently developed vortex electron beams (VEBs), made up of electrons with orbital angular momentum, which could, in addition, probe induced magnetic near fields. In this work we revisit the theoretical description of this technique, dubbed vortex electron energy-loss spectroscopy (v-EELS). We map the fundamental, quantum-mechanical picture of the scattering of the VEB electrons to the intuitive classical models, which treat the electron beams as a superposition of linear electric and magnetic currents. We then apply this formalism to characterize the optical response of dielectric nanoantennas with v-EELS. Our calculations reveal that VEB electrons probe electric or magnetic modes with different efficiency, which can be adjusted by changing either beam vorticity or acceleration voltage to determine the nature of the probed excitations. We also study a chirally arranged nanostructure, which in the interaction with electron vortices produces dichroism in electron-energy-loss spectra. Our theoretical work establishes VEBs as versatile probes that could provide information on optical excitations otherwise inaccessible with conventional electron beams.

It is of fundamental interest to probe dynamics excitations such as magnons with nanoscale wavelengths in matter. Here, the authors experimentally observe magnons with high k-vectors using Brillouin light scattering microscopy with the use of dielectric nanoresonators, which opens the way for the future nanoscale magnonics research and probing materials with high-momentum photons. Local probing of dynamic excitations such as magnons and phonons in materials and nanostructures can bring new insights into their properties and functionalities. For example, in magnonics, many concepts and devices recently demonstrated at the macro- and microscale now need to be realized at the nanoscale. Brillouin light scattering (BLS) spectroscopy and microscopy has become a standard technique for spin wave characterization, and enabled many pioneering magnonic experiments. However, the conventional BLS cannot detect nanoscale waves due to its fundamental limit in maximum detectable quasiparticle momentum. Here we show that optically induced Mie resonances in nanoparticles can be used to extend the range of accessible quasiparticle's wavevectors beyond the BLS fundamental limit. These experiments involve the measurement of thermally excited as well as coherently excited high momentum magnons. Our findings demonstrate the capability of Mie-enhanced BLS and significantly extend the usability of BLS microscopy for magnonic and phononic research.

Ice losses from the Greenland and Antarctic ice sheets have accelerated since the 1990s, accounting for a significant increase in the global mean sea level. Here, we present a new 29-year record of ice sheet mass balance from 1992 to 2020 from the Ice Sheet Mass Balance Inter-comparison Exercise (IMBIE). We compare and combine 50 independent estimates of ice sheet mass balance derived from satellite observations of temporal changes in ice sheet flow, in ice sheet volume, and in Earth's gravity field. Between 1992 and 2020, the ice sheets contributed 21.0±1.9g€¯mm to global mean sea level, with the rate of mass loss rising from 105g€¯Gtg€¯yr-1 between 1992 and 1996 to 372g€¯Gtg€¯yr-1 between 2016 and 2020. In Greenland, the rate of mass loss is 169±9g€¯Gtg€¯yr-1 between 1992 and 2020, but there are large inter-annual variations in mass balance, with mass loss ranging from 86g€¯Gtg€¯yr-1 in 2017 to 444g€¯Gtg€¯yr-1 in 2019 due to large variability in surface mass balance. In Antarctica, ice losses continue to be dominated by mass loss from West Antarctica (82±9g€¯Gtg€¯yr-1) and, to a lesser extent, from the Antarctic Peninsula (13±5g€¯Gtg€¯yr-1). East Antarctica remains close to a state of balance, with a small gain of 3±15g€¯Gtg€¯yr-1, but is the most uncertain component of Antarctica's mass balance. The dataset is publicly available at 10.5285/77B64C55-7166-4A06-9DEF-2E400398E452 (IMBIE Team, 2021).

In the present work, fibroin, and polyvinyl alcohol (PVA) - based films were biofunctionalized using two different techniques, the first by carbodiimide coupling and second by exploiting electrostatic interactions, seeking to achieve antithrombogenic behavior on the surface of the manufactured films for their potential use as biomaterials for the manufacture of cardiovascular implants. The biofunctionalized samples were submitted to the blood clotting test to verify the success of said biofunctionalization. The results showed that the samples biofunctionalized by carbodiimide coupling, in addition to presenting a higher antithrombogenic activity than those biofunctionalized by taking advantage of electrostatic interactions, presented contact angles values closer to those of the materials for the manufacture of cardiovascular implants, and that also, the biofunctionalization does not significantly affect the mechanical and surface properties of the fabricated films, RESUMEN En el presente trabajo, se biofuncionalizaron con heparina películas fabricadas a base de fibroína (SF) y polivinil alcohol (PVA) utilizando dos técnicas diferentes, la primera por acople de carbodiimida y la segunda por aprovechamiento de interacciones electrostáticas, buscando conseguir un comportamiento antitrombogénico en la superficie de las películas fabricas para su potencial uso como biomateriales para la fabricación de implantes cardiovasculares. Las muestras biofuncionalizadas fueron sometidas a una prueba de coagulación de sangre para verificar el éxito de dicha biofuncionalización. Los resultados mostraron que las muestras biofuncionalizadas por acople de carbodiimida, además de presentar una actividad antitrombogénica superior a las biofuncionalizadas por aprovechamiento de interacciones electrostáticas, presentaban valores de ángulos de contacto más cercanos a los de los materiales para la fabricación de implantes cardiovasculares, y que también, la biofuncionalización no afecta significativamente las propiedades mecánicas y superficiales de las películas fabricadas.

In chronic hepatitis B virus (HBV) infection, hepatitis B e antigen (HBeAg) and hepatitis B surface antigen (HBsAg) clearance are important milestones toward immune control.1 A drop in HBV DNA is an established correlate of both HBeAg and HBsAg clearance.2 We evaluated changes in HBV RNA and hepatitis B core-related antigen (HBcrAg) levels, markers of transcriptional activity of covalently closed circular DNA (cccDNA),3,4 with HBeAg and HBsAg clearance, and compared them with changes in HBV DNA level among adult participants in the Hepatitis B Research Network (HBRN).

©2023 American Physical Society This work was supported by the French Agence Nationale de la Recherche (ANR), project SurMott, Ref. No. NT-09-618999. We acknowledge financial support from the Spanish Ministry of Science and Innovation through Projects No. MAT2017-88258-R, No. PID2021-123295NB-I00, No. PID2020-117024GB-C43, No. PID2021-125604NB-I00, and No. CEX2018-000805-M (María de Maeztu Programme for Units of Excellence in R&D). We also acknowledge the technical support provided by the Centro de Computación Científica-UAM (CCC-UAM), Project No. BIOFAST. We thank Professor D. Farías for many helpful discussions., We report an experimental and theoretical study of the electron-phonon coupling for alpha-Sn/Ge(111), a prototypical triangular lattice surface, closely related to Sn/Si(111)-( √3 x √3), where recent experimental evidence has found superconductivity [X. Wu et al., Phys. Rev. Lett. 125, 117001 (2020)]. We concentrate our study on the (3 x 3) phase of alpha-Sn/Ge(111) that appears between 150 and 120 K and has a well-known geometry with a half-filled electronic band around the Fermi energy. We show that this surface presents a giant electron-phonon interaction that can be considered at least partially responsible for the different phases that this system shows at very low temperature. Our theoretical results indicate that indeed the electron-phonon interaction in alpha-Sn/Ge(111)-(3 x 3) is unusually large, since we find that lambda, the electron mass enhancement for the half-filled band, is lambda = 1.3. This result is in good agreement with the experimental value obtained from high-resolution angle-resolved photoemission spectroscopy measurements, which yield lambda = 1.45 +/- 0.1, Ministerio de Ciencia e Innovación (MICINN), Unidades de Excelencia María de Maeztu (MICINN), French Agence Nationale de la Recherche (ANR), Depto. de Física de Materiales, Fac. de Ciencias Físicas, TRUE, pub

The development of anti-icing robust surfaces is a hot topic nowadays and particularly crucial in the aeronautics or wind energy sectors as ice accretion can compromise safety and power generation efficiency. However, the current performance of most anti-icing strategies has been proven insufficient for such demanding applications, particularly in large unprotected zones, which located downstream from thermally protected areas, may undergo secondary icing. Herein, a new testing methodology is proposed to evaluate accretion mechanisms and secondary icing phenomena through, respectively, direct impact and running-wet processes and systematically applied to anti-icing materials including commercial solutions and the latest trends in the state-of-the-art. Five categories of materials (hard, elastomeric, polymeric matrix, SLIPS and superhydrophobic) with up to fifteen formulations have been tested. This Round-Robin approach provides a deeper understanding of anti-icing mechanisms revealing the strengths and weaknesses of each material. The conclusion is that there is no single passive solution for anti-ice protection. Thus, to effectively protect a given real component, different tailored materials fitted for each particular zone of the system are required. For this selection, shape analysis of such a component and the impact characteristics of water droplets under real conditions are needed as schematically illustrated for aeronautic turbines.

The study aims to deepen the understanding of turbulent flows above waves, particularly investigating the interaction of wave structure to the airflow separation and its influence on the drag above wind-waves. A series of experimental studies were performed in this research to examine the behaviour of airflow separation above wind-waves, evaluate the important wave components and spectrum in relation to the wave boundary layer, and investigate the role of small-scale ripples on wave turbulence. The drag coefficient Cd is an essential parameter in air-sea momentum transfer. However, its relationship with wind speed U10 has remained scattered and uncertain for over 30 years. Multiple factors, such as wave steepness, wave breaking, gustiness of the wind, non-linear wind-wave interactions, and wave directionality, can affect Cd, leading to deviations from the predictions of climate models. Furthermore, recent field observations by Powell et al. (2003) and Jarosz et al. (2007) have documented drag coefficient saturation and reduction behaviour during hurricanes. The literature suggests that deviations from predicted drag coefficients, especially at high wind speeds, may be related to airflow separation. The airflow separation in the leeward side of wave crests is often observed and may be linked to the occurrence of small-scale waves. Surface tension has been found to cause the formation of ripples at the leeward side of crests, and the interaction of these small-scale ripples with larger waves is important due to their impact on radiation stress and viscosity. The small-scale waves in the gravity-capillary regime are the main contributor to ocean roughness and affect air momentum transfer. However, a systematic investigation into the influence of gravity-capillary waves on the atmospheric boundary layer was lacking until the Direct Numerical Study (DNS) was conducted by Druzhinin et al. (2019). Therefore, this thesis aims to fill a gap in the current understanding of th

Solar cells are a promising optoelectronic device for the simultaneous solution of energy-resource and environmental problems. However, their high cost and slow, laborious production process so far severely hinder a sufficient widespread of clean, renewable photovoltaic energy as a major alternative electricity generator. This undesirable situation is mainly attributed to the fact that photovoltaic devices have been manufactured through a series of vacuum and high-temperature processes. Here we realize a PEDOT:PSS/Si heterojunction solar cell fabricated only in ambient and room-temperature conditions from a plain Si wafer, with an over-10% energy conversion efficiency. Our production scheme is based on our finding that PEDOT:PSS photovoltaic layers actively operate even on highly doped Si substrates, which substantially mitigates the condition requirements for electrode implementation. Our approach may pave the way for facile, low-cost, high-throughput solar cell fabrication, useful in various fields even including developing countries and educational sites.

Microcellular injection molding is an attractive method. However, their surface imperfections have been a major problem hindering wide industrial applications. Several methods have been proposed to improve the surface appearance of foams. In this study, we proposed a method to improve the surface appearance of polypropylene (PP) foams from the material property perspective, especially with regard to crystallization and viscosity. The basic idea of the surface improvement is to reduce the size of bubbles generated at the flow front, delay the solidification behavior of the polymer at the mold interface, squeeze the bubbles existing at the mold–polymer interface, and redissolve the bubbles into the polymer by holding pressure. Blending a low-modulus PP delays the crystallization of the polymers at the skin layer and solidification, taking enough time to squeeze the bubbles smaller. A sorbitol-based gelling agent, bis-O-([4 methylphenyl]methylene)-D-Glucitol, was used to increase the viscosity at a low strain rate to reduce the size of the bubbles generated at the flow front during the filling stage. The foam injection molding experiments demonstrated that the proposed method effectively improved the surface appearance of the foams. In particular, the surface appearance of the foams became almost equivalent to that of solid samples using low-modulus PP.

Senior leaders onboard U.S. Navy vessels afloat have constantly evolving schedules that are rarely consistent from day to day. Over the past two decades, studies of work and rest patterns have confirmed anecdotal reports of insufficient sleep of enlisted Sailors. The sleep of senior Officers has not been closely examined. Assessing sleep of surface fleet Officers as they perform their duties in the fleet may provide insight into the bigger picture of health and wellness in the U.S. Navy. As part of a multi-year project, sleep patterns of senior leaders were assessed while in training and in the fleet. An 18-month longitudinal data collection commenced when participants were attending Surface Warfare Schools Command (SWSC) in Newport, RI, and continued as participants assumed their operational positions in the fleet. This thesis takes an initial look into the sleep, mood, and other physiological patterns of senior leaders in these two settings over the first few months of the study. Participants completed validated questionnaires to assess their overall wellbeing and wore physiological monitors (ŌURA rings) to assess the duration and quality of their sleep. In this first opportunity to examine patterns in the data, we found statistically significant differences in sleep duration of senior leaders depending on where they were living and working; that is, when they were attending school, between school and operational command, and after they arrived at their operational command., Lieutenant, United States Navy, Approved for public release. Distribution is unlimited.

This paper investigates metaphorical and phenomenological aspects of shimmer, reflection, membrane and movement. By exploring the interface of knowledge through the lens of materiality, the aim is to examine how the plasticity of light and shadows might create animating reflections and dissolving surfaces. Of particular interest is the undefined quality of shimmer and how it can be interpreted as a transitional in-between stage of displaced and fluid boundaries. Further on, the work explores the power of portals – both visually but also in the physical and emotional engagement with materials and techniques. The installation Mystery of Matter and Magic of Presence is based upon a dialogical method where the atmosphere might be understood as a space-filling materiality itself. The work expresses the material’s state as well as the ephemeral qualities around it. It offers a counterweight to a hard, violent and narcissistic aspect of the material biographies of metals in general, and aluminum in particular. The research consists mainly of sources on Byzantine and Medieval Art history. Sources that also engage with the role of language, poetry and etymology for our understanding of material culture and history.

Medical implants have improved the quality of life of many patients. However, surgical intervention may eventually lead to implant microbial contamination. The aims of this research were to develop an easy, robust, quantitative assay to assess surface antimicrobial activities, especially the anti-nascent biofilm activity, and to identify control surfaces, allowing for international comparisons. Using new antimicrobial assays to assess the inhibition of nascent biofilm during persistent contact or after transient contact with bacteria, we show that the 5 cent Euro coin or other metal-based antibacterial coins can be used as positive controls, as more than 4 log reduction on bacterial survival was observed when using either S. aureus or P. aeruginosa as targets. The methods and controls described here could be useful to develop an easy, flexible and standardizable assay to assess relevant antimicrobial activities of new implant materials developed by industries and academics.

This paper investigates metaphorical and phenomenological aspects of shimmer, reflection, membrane and movement. By exploring the interface of knowledge through the lens of materiality, the aim is to examine how the plasticity of light and shadows might create animating reflections and dissolving surfaces. Of particular interest is the undefined quality of shimmer and how it can be interpreted as a transitional in-between stage of displaced and fluid boundaries. Further on, the work explores the power of portals – both visually but also in the physical and emotional engagement with materials and techniques. The installation Mystery of Matter and Magic of Presence is based upon a dialogical method where the atmosphere might be understood as a space-filling materiality itself. The work expresses the material’s state as well as the ephemeral qualities around it. It offers a counterweight to a hard, violent and narcissistic aspect of the material biographies of metals in general, and aluminum in particular. The research consists mainly of sources on Byzantine and Medieval Art history. Sources that also engage with the role of language, poetry and etymology for our understanding of material culture and history.

Medical implants have improved the quality of life of many patients. However, surgical intervention may eventually lead to implant microbial contamination. The aims of this research were to develop an easy, robust, quantitative assay to assess surface antimicrobial activities, especially the anti-nascent biofilm activity, and to identify control surfaces, allowing for international comparisons. Using new antimicrobial assays to assess the inhibition of nascent biofilm during persistent contact or after transient contact with bacteria, we show that the 5 cent Euro coin or other metal-based antibacterial coins can be used as positive controls, as more than 4 log reduction on bacterial survival was observed when using either S. aureus or P. aeruginosa as targets. The methods and controls described here could be useful to develop an easy, flexible and standardizable assay to assess relevant antimicrobial activities of new implant materials developed by industries and academics.

It is of fundamental interest to probe dynamics excitations such as magnons with nanoscale wavelengths in matter. Here, the authors experimentally observe magnons with high k-vectors using Brillouin light scattering microscopy with the use of dielectric nanoresonators, which opens the way for the future nanoscale magnonics research and probing materials with high-momentum photons. Local probing of dynamic excitations such as magnons and phonons in materials and nanostructures can bring new insights into their properties and functionalities. For example, in magnonics, many concepts and devices recently demonstrated at the macro- and microscale now need to be realized at the nanoscale. Brillouin light scattering (BLS) spectroscopy and microscopy has become a standard technique for spin wave characterization, and enabled many pioneering magnonic experiments. However, the conventional BLS cannot detect nanoscale waves due to its fundamental limit in maximum detectable quasiparticle momentum. Here we show that optically induced Mie resonances in nanoparticles can be used to extend the range of accessible quasiparticle's wavevectors beyond the BLS fundamental limit. These experiments involve the measurement of thermally excited as well as coherently excited high momentum magnons. Our findings demonstrate the capability of Mie-enhanced BLS and significantly extend the usability of BLS microscopy for magnonic and phononic research.

The ground reaction force (GRF) recorded by a platform when a person stands upright lies at the interface between the neural networks controlling stance and the body sway deduced from centre of pressure (CoP) displacement. It can be decomposed into vertical (VGRF) and horizontal (HGRF) vectors. Few studies have addressed the modulation of the GRFs by the sensory conditions and their relationship with body sway. We reconsidered the features of the GRFs oscillations in healthy young subjects (n = 24) standing for 90 s, with the aim of characterising the possible effects of vision, support surface and adaptation to repeated trials, and the correspondence between HGRF and CoP time-series. We compared the frequency spectra of these variables with eyes open or closed on solid support surface (EOS, ECS) and on foam (EOF, ECF). All stance trials were repeated in a sequence of eight. Conditions were randomised across different days. The oscillations of the VGRF, HGRF and CoP differed between each other, as per the dominant frequency of their spectra (around 4 Hz, 0.8 Hz and <0.4 Hz, respectively) featuring a low-pass filter effect from VGRF to HGRF to CoP. GRF frequencies hardly changed as a function of the experimental conditions, including adaptation. CoP frequencies diminished to <0.2 Hz when vision was available on hard support surface. Amplitudes of both GRFs and CoP oscillations decreased in the order ECF > EOF > ECS ≈ EOS. Adaptation had no effect except in ECF condition. Specific rhythms of the GRFs do not transfer to the CoP frequency, whereas the magnitude of the forces acting on the ground ultimately determines body sway. The discrepancies in the time-series of the HGRF and CoP oscillations confirm that the body’s oscillation mode cannot be dictated by the inverted pendulum model in any experimental conditions. The findings emphasise the robustness of the VGRF “postural rhythm” and its correspondence with the cortical theta rhythm, shed new insight on

Medical implants have improved the quality of life of many patients. However, surgical intervention may eventually lead to implant microbial contamination. The aims of this research were to develop an easy, robust, quantitative assay to assess surface antimicrobial activities, especially the anti-nascent biofilm activity, and to identify control surfaces, allowing for international comparisons. Using new antimicrobial assays to assess the inhibition of nascent biofilm during persistent contact or after transient contact with bacteria, we show that the 5 cent Euro coin or other metal-based antibacterial coins can be used as positive controls, as more than 4 log reduction on bacterial survival was observed when using either S. aureus or P. aeruginosa as targets. The methods and controls described here could be useful to develop an easy, flexible and standardizable assay to assess relevant antimicrobial activities of new implant materials developed by industries and academics.

It is of fundamental interest to probe dynamics excitations such as magnons with nanoscale wavelengths in matter. Here, the authors experimentally observe magnons with high k-vectors using Brillouin light scattering microscopy with the use of dielectric nanoresonators, which opens the way for the future nanoscale magnonics research and probing materials with high-momentum photons. Local probing of dynamic excitations such as magnons and phonons in materials and nanostructures can bring new insights into their properties and functionalities. For example, in magnonics, many concepts and devices recently demonstrated at the macro- and microscale now need to be realized at the nanoscale. Brillouin light scattering (BLS) spectroscopy and microscopy has become a standard technique for spin wave characterization, and enabled many pioneering magnonic experiments. However, the conventional BLS cannot detect nanoscale waves due to its fundamental limit in maximum detectable quasiparticle momentum. Here we show that optically induced Mie resonances in nanoparticles can be used to extend the range of accessible quasiparticle's wavevectors beyond the BLS fundamental limit. These experiments involve the measurement of thermally excited as well as coherently excited high momentum magnons. Our findings demonstrate the capability of Mie-enhanced BLS and significantly extend the usability of BLS microscopy for magnonic and phononic research.

It is of fundamental interest to probe dynamics excitations such as magnons with nanoscale wavelengths in matter. Here, the authors experimentally observe magnons with high k-vectors using Brillouin light scattering microscopy with the use of dielectric nanoresonators, which opens the way for the future nanoscale magnonics research and probing materials with high-momentum photons. Local probing of dynamic excitations such as magnons and phonons in materials and nanostructures can bring new insights into their properties and functionalities. For example, in magnonics, many concepts and devices recently demonstrated at the macro- and microscale now need to be realized at the nanoscale. Brillouin light scattering (BLS) spectroscopy and microscopy has become a standard technique for spin wave characterization, and enabled many pioneering magnonic experiments. However, the conventional BLS cannot detect nanoscale waves due to its fundamental limit in maximum detectable quasiparticle momentum. Here we show that optically induced Mie resonances in nanoparticles can be used to extend the range of accessible quasiparticle's wavevectors beyond the BLS fundamental limit. These experiments involve the measurement of thermally excited as well as coherently excited high momentum magnons. Our findings demonstrate the capability of Mie-enhanced BLS and significantly extend the usability of BLS microscopy for magnonic and phononic research.

Medical implants have improved the quality of life of many patients. However, surgical intervention may eventually lead to implant microbial contamination. The aims of this research were to develop an easy, robust, quantitative assay to assess surface antimicrobial activities, especially the anti-nascent biofilm activity, and to identify control surfaces, allowing for international comparisons. Using new antimicrobial assays to assess the inhibition of nascent biofilm during persistent contact or after transient contact with bacteria, we show that the 5 cent Euro coin or other metal-based antibacterial coins can be used as positive controls, as more than 4 log reduction on bacterial survival was observed when using either S. aureus or P. aeruginosa as targets. The methods and controls described here could be useful to develop an easy, flexible and standardizable assay to assess relevant antimicrobial activities of new implant materials developed by industries and academics.

The ground reaction force (GRF) recorded by a platform when a person stands upright lies at the interface between the neural networks controlling stance and the body sway deduced from centre of pressure (CoP) displacement. It can be decomposed into vertical (VGRF) and horizontal (HGRF) vectors. Few studies have addressed the modulation of the GRFs by the sensory conditions and their relationship with body sway. We reconsidered the features of the GRFs oscillations in healthy young subjects (n = 24) standing for 90 s, with the aim of characterising the possible effects of vision, support surface and adaptation to repeated trials, and the correspondence between HGRF and CoP time-series. We compared the frequency spectra of these variables with eyes open or closed on solid support surface (EOS, ECS) and on foam (EOF, ECF). All stance trials were repeated in a sequence of eight. Conditions were randomised across different days. The oscillations of the VGRF, HGRF and CoP differed between each other, as per the dominant frequency of their spectra (around 4 Hz, 0.8 Hz and <0.4 Hz, respectively) featuring a low-pass filter effect from VGRF to HGRF to CoP. GRF frequencies hardly changed as a function of the experimental conditions, including adaptation. CoP frequencies diminished to <0.2 Hz when vision was available on hard support surface. Amplitudes of both GRFs and CoP oscillations decreased in the order ECF > EOF > ECS ≈ EOS. Adaptation had no effect except in ECF condition. Specific rhythms of the GRFs do not transfer to the CoP frequency, whereas the magnitude of the forces acting on the ground ultimately determines body sway. The discrepancies in the time-series of the HGRF and CoP oscillations confirm that the body’s oscillation mode cannot be dictated by the inverted pendulum model in any experimental conditions. The findings emphasise the robustness of the VGRF “postural rhythm” and its correspondence with the cortical theta rhythm, shed new insight on

© 2004 IOP Publishing Ltd. This work is carried out in the framework of a European Marie Curie project (HPMT-CT-2001-00215). Support of MCYT (MAT2003-00455) is acknowledged., The effect of electrochemical etching of n-type GaSb in aqueous solutions of HCl and HF has been analysed. By anodization in HCl, two different morphologies of porous layers were observed depending on the current density. At low current density (0.5 mA cm_(-2)) a macroporous layer is formed with the pores following preferential directions, while at high current density (15 mA cm_(-2)) pores of sizes less than 100 nm were observed. Furthermore, a comparison between the luminescence in the porous layer and bulk GaSb is also performed. On the other hand, anodization in HF leads to an electropolishing process and no porosification is obtained., European Marie Curie project, MCYT, Depto. de Física de Materiales, Fac. de Ciencias Físicas, TRUE, pub

© 2004 IOP Publishing Ltd. International Workshop on Beam Injection Assessment of Microstructures in Semconductors ( 7. 2003. Lille, Francia). This work was supported by MCYT (ProjectMAT2000-2119). RP thanks MCYT for a research grant from the NATO scientific programme., Polycrystalline samples of titanium oxide were prepared by thermal sintering, in argon and air atmospheres at temperatures ranging from 1100 to 1500 degreesC, from powders of anatase and rutile phases. The samples sintered in argon were further treated in oxygen at the temperature of 800 degreesC for intervals of time up to 8 h. The luminescence emission of the initial powders was situated in the green region, with the peak at 580 nm. The sintering treatment in argon leads to a decrease of the luminescence intensity that appears as a broad band peaked at 550 nm in the case of anatase and as a band peaked at 450 nm in the case of the rutile phase. The sintering treatment in air causes the quenching of the emission in the visible region. In both cases, a sharp and intense emission appears in the infrared region at 800 nm for rutile and 820 nm for the anatase phase. The blue emission is sensitive to the treatment in oxygen atmosphere which causes mainly an intensity increase of the band at 450 nm. The treatment in oxygen results in the reconstruction of the polycrystalline sample surface as hexagonal shape protrusions and large terraces., MCYT, NATO scientific programme, Depto. de Física de Materiales, Fac. de Ciencias Físicas, TRUE, pub

© 2007 Elsevier B.V. This work has been supported by the DPI2005-02860 project of the Ministerio de Educación y Ciencia of Spain and the “Tecnologías en ecología, alta precisión y productividad, multifuncionalidad, y tecnologías de la información y comunicaciones en Máquina Herramienta” CENIT project of the Ministerio de Industria, turismo y comercio. Sánchez-Brea is currently contracted by the Universidad Complutense de Madrid under the “Ramón y Cajal” research program of the Ministerio de Educación y Ciencia of Spain., Metallic gratings can be found in applications such as optical metrology. Due to their fabrication process, the surface presents a certain roughness. In this work, the effect of roughness on Talbot effect has been analyzed when the grating is illuminated with a Gaussian beam. A model based on Fresnel regime is used in order to determine the intensity distribution in the near field. Contrast of the self-images is obtained and it is found that it decreases in terms of the distance between the grating and the observation plane. When the autocorrelation function of roughness presents a Gaussian behaviour, the diffracted beams are still Gaussian although some of their properties change. For example, the width of the diffracted beams increases with respect to the case of the standard chrome on glass gratings. On the other hand, the power of each diffracted beam is independent on the roughness properties of the surface., Ministerio de Educación y Ciencia (MEC), España, Ministerio de Industria, Turismo y Comercio, España, Universidad Complutense de Madrid (UCM), Depto. de Óptica, Fac. de Ciencias Físicas, TRUE, pub

© 2008 The American Physical Society. We are very grateful to J.F. Bartolomé, S. Gallego, C. Pecharromán, and J.S. Moya for many fruitful discussions. This work was supported by the Spanish Ministry of Education and Science under Project No. MAT2006-05122., Several studies of the decohesion properties of various oxide/metal systems have been performed recently by ab initio calculations. However, the use of different computational methods, which involve diverse approximations, energy functionals, or calculation conditions, makes the identification of general trends difficult. In the present work, a broad range of interfaces between an ionic oxide (Al_(2)O_(3), ZrO_(2), HfO_(2), and MgO) and a metal [either transition metal (TM) or Na], has been investigated systematically in order to find correlations among the work of separation (Wsep) and the intrinsic properties of the interface, such as the crystal structure, the strain conditions, or the electronic properties of both constituents. Our main result is that the calculated Wsep adjusts very accurately to a parabolic dependence on the summed surface energies of the metal and the oxide, regardless of the oxide and metal components, crystal lattices, interface orientations, and atomic terminations. Furthermore, Wsep is mostly determined by the surface energies although for interfaces involving nonpolar oxide surfaces the contribution of the interfacial energy is not negligible. The strongest adhesion is found for interfaces formed by polar surfaces and bcc TM, e.g., the Wsep of ZrO_(2)(001)_(O)/TM interfaces changes almost by a factor of 2 depending on whether the TM has bcc or fcc structure. In addition, a correlation between the strain conditions of the equilibrium interface structure and the adhesion properties has been obtained. Finally, in order to predict metal/oxide systems whose mechanical properties are reinforced by the plastic deformation of the metal, we examine the expected behavior of the system beyond the elastic regime in the light of the calculated adherence at the interface. The comparison with the scarcely available experimental data provides good agreement for both the Wsep and the qualitative prediction of mechanical reinforcement., Spanish Ministry of Education and Science, Depto. de Estructura de la Materia, Física Térmica y Electrónica, Fac. de Ciencias Físicas, TRUE, pub

© 2010 IOP Publishing Ltd. This work was supported by MEC through projects MAT2006-01259 and MAT2009-07882., CuO nanostructures with different morphologies, such as single-crystal nanowires, nanoribbons and nanorods, have been grown by thermal oxidation of copper in the 380–900 °C temperature range. Cathodoluminescence spectra of the nanostructures show a band peaked at 1.31 eV which is associated with near band gap transitions of CuO. Two additional bands centred at about 1.23 and 1.11 eV, suggested to be due to defects, are observed for nanostructures grown at high temperatures. The magnetic behaviour of nanowires with lengths in the range of several micrometres and diameters of 50–120 nm has been investigated. Hysteresis loops of the nanowires show ferromagnetic behaviour from 5 K to room temperature., MEC (Ministerio de Educación y Ciencia, España), Depto. de Física de Materiales, Fac. de Ciencias Físicas, TRUE, pub

© 2014 IOP Publishing Ltd and Deutsche Physikalische Gesellschaft. AD thanks the FRS-FNRS Belgium for financial support and N Goldman and P Gaspard for support and valuable discussions. We acknowledge support by the Spanish MICINN grants FIS2009-10061 and FIS2012-33152, the CAM research consortium QUITEMAD S2009-ESP- 1594, the European Commission PICC: FP7 2007-2013, Grant No. 249958, and the UCM-BS grant GICC-910758., We propose and construct a numerical algorithm to calculate the Berry conductivity in topological band insulators. The method is applicable to cold atom systems as well as solid state setups, both for the insulating case where the Fermi energy lies in the gap between two bulk bands as well as in the metallic regime. This method interpolates smoothly between both regimes. The algorithm is gauge-invariant by construction, efficient, and yields the Berry conductivity with known and controllable statistical error bars. We apply the algorithm to several paradigmatic models in the field of topological insulators, including Haldaneʼs model on the honeycomb lattice, the multi-band Hofstadter model, and the BHZ model, which describes the 2D spin Hall effect observed in CdTe/HgTe/CdTe quantum well heterostructures., FRS-FNRS Belgium, Spanish MICINN, CAM consortium QUITEMAD, European Commission PICC: FP7 2007-2013, UCM-BS, Depto. de Física Teórica, Fac. de Ciencias Físicas, TRUE, pub

We study the stability and evolution of various elastic defects in a flat graphene sheet and the electronic properties of the most stable configurations. Two types of dislocations are found to be stable: 'glide' dislocations consisting of heptagon-pentagon pairs, and 'shuffle' dislocations, an octagon with a dangling bond. Unlike the most studied case of carbon nanotubes, Stone Wales defects seem to be dynamically unstable in the planar graphene sheet. Similar defects in which one of the pentagon-heptagon pairs is displaced vertically with respect to the other one are found to be dynamically stable. Shuffle dislocations will give rise to local magnetic moments that can provide an alternative route to magnetism in graphene., Spanish MECD, Autonomous Region of Madrid, Depto. de Análisis Matemático y Matemática Aplicada, Fac. de Ciencias Matemáticas, TRUE, pub

Workshop on Dielectrics in Microelectronics (10. 1999. Barcelona). © Elsevier Science Ltd. The authors would like to thank CAI de Implantación Iónica from the Complutense University in Madrid for technical assistance with the ECR-CVD system. This research was partially supported by the Spanish government under Grant no. TIC 98/0740., Cleaning of InP surfaces using electron cyclotron resonance (ECR) nitrogen plasmas has been studied. Electrical performance of Al/SiNx:H/InP structures has been analysed to determine the effect of the plasma cleaning. The SINx:H insulator layers are deposited at 200 degrees C using an ECR chemical vapour deposition technique. It is observed that a 30 s low-power (60 W) ECR N-2 plasma treatment of InP surface reduces the interface defects and improves the resistivity and breakdown held values of the SiNx:H. (C) 2000 Elsevier Science Ltd. All rights reserved., Spanish government, Depto. de Estructura de la Materia, Física Térmica y Electrónica, Fac. de Ciencias Físicas, TRUE, pub

© 2010 American Institute of Physics. We acknowledge financial support from Spanish MICINN Grant No. MAT2009-08024, Consolider-Ingenio Grant No. CSD2007-00041, and NanoAraCat. C.M.B. and Z.K. grant financial support through the Ramón y Cajal program. J.A. also acknowledges LMA advanced microscopy laboratory at INA for the use of advanced Cs-corrected electron microscopes., In this work we report on the magnetic behavior of MgO thin films prepared by sputtering. A severe aging process of the ferromagnetic properties is detected in magnetic samples exposed to ambient atmosphere. However, ferromagnetism can be successively switched on again by annealing samples in vacuum. We suggest this behavior reflects the key role played by defects in stabilizing ferromagnetism in MgO films and is likely to be closely related to the hydrogen-driven instability of V-type centers in this material., Ministerio de Ciencia e Innovación (MICINN), Consolider-Ingenio, NanoAraCat., Ramón y Cajal program, Depto. de Estructura de la Materia, Física Térmica y Electrónica, Fac. de Ciencias Físicas, TRUE, pub

© Institute of Physics. International Workshop on LEEM/PEEM (6. 2008. Trieste, Italia). This research was partly supported by the Office of Basic Energy Sciences, Division of Materials Sciences, U.S. Department of Energy under Contracts No. DE-AC04¬94AL85000 and No. DE¬AC02¬05CH11231, by the Spanish Ministry of Education and Science through Projects MAT2006¬13149¬C02-02. B.S. acknowledges support to the Spanish Ministry of Education and Science from an FPI fellowship., We have grown epitaxial films a few atomic layers thick of iron oxides on ruthenium. We characterize the growth by low energy electron microscopy. Using selected-area diffraction and intensity-versus-voltage spectroscopy, we detect two distinct phases which are assigned as wustite and magnetite. Spin-polarized low energy electron microscopy reveals magnetic domain patterns in the magnetite phase at room temperature., Office of Basic Energy Sciences, Division of Materials Sciences, U.S. Department of Energy, Spanish Ministry of Education and Science, Depto. de Física de Materiales, Fac. de Ciencias Físicas, TRUE, pub