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Effective models focused on pertinent low-energy degrees of freedom have substantially contributed to our qualitative understanding of quantum materials. An iconic example, the Kondo model, was key to demonstrating that the rich phase diagrams of correlated metals originate from the interplay of localized and itinerant electrons. Modern electronic structure calculations suggest that to achieve quantitative material-specific models, accurate consideration of the crystal field and spin-orbit interactions is imperative. This poses the question of how local high-energy degrees of freedom become incorporated into a collective electronic state. Here, we use resonant inelastic x-ray scattering (RIXS) on CePd3 to clarify the fate of all relevant energy scales. We find that even spin-orbit excited states acquire pronounced momentum-dependence at low temperature-the telltale sign of hybridization with the underlying metallic state. Our results demonstrate how localized electronic degrees of freedom endow correlated metals with new properties, which is critical for a microscopic understanding of superconducting, electronic nematic, and topological states.

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We performed x-ray magnetic circular dichroism (XMCD) measurements on heterostructures comprising topological insulators (TIs) of the (Bi,Sb)_{2}(Se,Te)_{3} family and the magnetic insulator EuS. XMCD measurements allow us to investigate element-selective magnetic proximity effects at the very TI/EuS interface. A systematic analysis reveals that there is neither significant induced magnetism within the TI nor an enhancement of the Eu magnetic moment at such interface. The induced magnetic moments in Bi, Sb, Te, and Se sites are lower than the estimated detection limit of the XMCD measurements of ∼10^{-3} µ_{B}/at.

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We show that hybrid MnOx/C60 heterojunctions can be used to design a storage device for spin-polarized charge: a spin capacitor. Hybridization at the carbon-metal oxide interface leads to spin-polarized charge trapping after an applied voltage or photocurrent. Strong electronic structure changes, including a 1-eV energy shift and spin polarization in the C60 lowest unoccupied molecular orbital, are then revealed by x-ray absorption spectroscopy, in agreement with density functional theory simulations. Muon spin spectroscopy measurements give further independent evidence of local spin ordering and magnetic moments optically/electronically stored at the heterojunctions. These spin-polarized states dissipate when shorting the electrodes. The spin storage decay time is controlled by magnetic ordering at the interface, leading to coherence times of seconds to hours even at room temperature.

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Platelets of strontium hexaferrite (SrFe12O19, SFO), up to several micrometers in width, and tens of nanometers thick have been synthesized by a hydrothermal method. They have been studied by a combination of structural and magnetic techniques, with emphasis on Mössbauer spectroscopy and X-ray absorption based-measurements including spectroscopy and microscopy on the iron-L edges and the oxygen-K edge, allowing us to establish the differences and similarities between our synthesized nanostructures and commercial powders. The Mössbauer spectra reveal a greater contribution of iron tetrahedral sites in platelets in comparison to pure bulk material. For reference, high-resolution absorption and dichroic spectra have also been measured both from the platelets and from pure bulk material. The O-K edge has been reproduced by density functional theory calculations. Out-of-plane domains were observed with 180° domain walls less than 20 nm width, in good agreement with micromagnetic simulations.

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Graphene-spaced magnetic systems with antiferromagnetic exchange-coupling offer exciting opportunities for emerging technologies. Unfortunately, the in-plane graphene-mediated exchange-coupling found so far is not appropriate for realistic exploitation, due to being weak, being of complex nature, or requiring low temperatures. Here we establish that ultra-thin Fe/graphene/Co films grown on Ir(111) exhibit robust perpendicular antiferromagnetic exchange-coupling, and gather a collection of magnetic properties well-suited for applications. Remarkably, the observed exchange coupling is thermally stable above room temperature, strong but field controllable, and occurs in perpendicular orientation with opposite remanent layer magnetizations. Atomistic first-principles simulations provide further ground for the feasibility of graphene-spaced antiferromagnetic coupled structures, confirming graphene's direct role in sustaining antiferromagnetic superexchange-coupling between the magnetic films. These results provide a path for the realization of graphene-based perpendicular synthetic antiferromagnetic systems, which seem exciting for fundamental nanoscience or potential use in spintronic devices.Antiferromagnetic spintronics may pave the way to innovative information storage devices with perpendicular coupling, however experimental demonstrations are still sparse. Here, the authors demonstrate a graphene-mediated perpendicular antiferromagnetic coupling between Fe and Co layers in a Fe/graphene/Co sandwich structure.

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Introducción. El objetivo fue conocer la prevalencia de antecedentes familiares de cáncer colorrectal (CCR) en la población de entre 40 y 75 años, así como la aceptabilidad y realización de pruebas de detección precoz. Material y métodos. Estudio descriptivo transversal, con emplazamiento en los centros de salud El Coto y El Llano (Gijón). Participaron 800 individuos con edades entre 40 y 75 años seleccionados mediante muestreo aleatorio simple, a los que se realizó un cuestionario telefónicamente, estudiando antecedentes familiares (AF) de CCR, edad al diagnóstico, realización de sangre oculta en heces (SOH)/colonoscopia, motivo de realización y/o rechazo y variables sociodemográficas. Resultados. Fueron válidos 664 cuestionarios. La prevalencia de AF fue el 15,8% (intervalo de confianza del 12,9 al 18,6). Con al menos un familiar de primer grado diagnosticado de CCR el 8,8%. Habían realizado previamente la prueba de SOH el 7,1% y colonoscopia el 17,9%, en su mayoría por motivos clínicos. La aceptabilidad fue del 90,7% para la SOH y del 65,2% para la colonoscopia. El principal motivo de rechazo de SOH fue la creencia de que el diagnóstico precoz no cambiaría el pronóstico y en la colonoscopia la incomodidad o miedo a la prueba. Conclusiones. Baja tasa de realización de pruebas por AF. Gran aceptabilidad para SOH y baja para colonoscopia. Se considera necesario tener en cuenta aspectos que afectan a la población general (motivos de rechazo, necesidad de información clara) y coordinación entre atención primaria, especializada y salud pública (AU)

Introduction. The objective of this study was to determine the prevalence of family history of colorectal cancer (CRC) in a population between 40 and 75 years-old, as well as acceptability and early diagnosis tests made. Material and methods. Cross-sectional study. Location: El Coto and El Llano (Gijon) primary care health centres. A total of 800 individuals aged between 40 and 75 years participated, selected by simple random sampling. Key measurements: questionnaire conducted by telephone with previous notice by newsletter. The variables studied were: family history (FH) of CRC, age at diagnosis, performance of faecal occult blood test (FOBT)/colonoscopy, reason for doing it or refusing it, and sociodemographic data. Results. A total of 664 questionnaires were valid. The prevalence of FH was 15.8% (confidence interval 12.9 to 18.6), with 8.8% with at least one first degree relative. An FOBT screening had been performed on 7.1%, and 17.9% had undergone colonoscopies, mostly on clinical grounds. Acceptability was 90.7% for FOBT and 65.2% for colonoscopy. Main reason for the refusal of an FOBT was the belief that early diagnosis would not alter prognosis. Main reason for rejection of colonoscopy was discomfort or fear of the test. Conclusions. There was a low rate of testing for FH, and a high acceptability for FOBT and a low acceptability for colonoscopy. Aspects affecting the general population (causes for rejection, need for clear information), as well as a correct coordination between Primary Care, specialized care, and public health, need to be reviewed (AU)

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RESUMEN

INTRODUCTION: The objective of this study was to determine the prevalence of family history of colorectal cancer (CRC) in a population between 40 and 75 years-old, as well as acceptability and early diagnosis tests made. MATERIAL AND METHODS: Cross-sectional study. LOCATION: El Coto and El Llano (Gijon) primary care health centres. A total of 800 individuals aged between 40 and 75 years participated, selected by simple random sampling. Key measurements: questionnaire conducted by telephone with previous notice by newsletter. The variables studied were: family history (FH) of CRC, age at diagnosis, performance of faecal occult blood test (FOBT)/colonoscopy, reason for doing it or refusing it, and sociodemographic data. RESULTS: A total of 664 questionnaires were valid. The prevalence of FH was 15.8% (confidence interval 12.9 to 18.6), with 8.8% with at least one first degree relative. An FOBT screening had been performed on 7.1%, and 17.9% had undergone colonoscopies, mostly on clinical grounds. Acceptability was 90.7% for FOBT and 65.2% for colonoscopy. Main reason for the refusal of an FOBT was the belief that early diagnosis would not alter prognosis. Main reason for rejection of colonoscopy was discomfort or fear of the test. CONCLUSIONS: There was a low rate of testing for FH, and a high acceptability for FOBT and a low acceptability for colonoscopy. Aspects affecting the general population (causes for rejection, need for clear information), as well as a correct coordination between Primary Care, specialized care, and public health, need to be reviewed.

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