366 research outputs found

    Electric field effects on magnetotransport properties of multiferroic Py/YMnO3/Pt heterostructures

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    We report on the exchange bias between antiferromagnetic and ferroelectric hexagonal YMnO3 epitaxial thin films sandwiched between a metallic electrode (Pt) and a soft ferromagnetic layer (Py). Anisotropic magnetoresistance measurements are performed to monitor the presence of an exchange bias field. When the heteroestructure is biased by an electric field, it turns out that the exchange bias field is suppressed. We discuss the dependence of the observed effect on the amplitude and polarity of the electric field. Particular attention is devoted to the role of current leakage across the ferroelectric layer.Comment: Accepted for publication in Philosophical Magazine Letters (Special issue on multiferroics

    Magnetically aligned dust and SiO maser polarisation in the envelope of the red supergiant VY Canis Majoris

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    International audienceWe use Atacama Large Millimeter/submillimeter Array Band 5 science verification observations of the red supergiant VY CMa to study the polarization of SiO thermal/masers lines and dust continuum at ~1.7 mm wavelength. We analyse both linear and circular polarization and derive the magnetic field strength and structure, assuming the polarization of the lines originates from the Zeeman effect, and that of the dust originates from aligned dust grains. We also discuss other effects that could give rise to the observed polarization. We detect, for the first time, significant polarization (~3%) of the circumstellar dust emission at millimeter wavelengths. The polarization is uniform with an electric vector position angle of 8\sim8^\circ. Varying levels of linear polarization are detected for the J=4-3 28SiO v=0, 1, 2, and 29SiO v=0, 1 lines, with the strongest polarization fraction of ~30% found for the 29SiO v=1 maser. The linear polarization vectors rotate with velocity, consistent with earlier observations. We also find significant (up to ~1%) circular polarization in several lines, consistent with previous measurements. We conclude that the detection is robust against calibration and regular instrumental errors, although we cannot yet fully rule out non-standard instrumental effects. Emission from magnetically aligned grains is the most likely origin of the observed continuum polarization. This implies that the dust is embedded in a magnetic field >13 mG. The maser line polarization traces the magnetic field structure. The magnetic field in the gas and dust is consistent with an approximately toroidal field configuration, but only higher angular resolution observations will be able to reveal more detailed field structure. If the circular polarization is due to Zeeman splitting, it indicates a magnetic field strength of ~1-3 Gauss, consistent with previous maser observations

    Microvascular cerebral blood flow fluctuations in association with apneas and hypopneas in acute ischemic stroke

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    Altres ajuts: The authors thank Dr. Arjun Yodh, Dr. John A. Detre, Dr. Janos Lückl, and Rosa Maria Miralda for their useful discussions. They acknowledge the support from Redes Temáticas de Investigación Cooperativa (RETICS-INVICTUS RD012/0014 and RETICS-INVICTUS PLUS RD16/0019/0010), the "Severo Ochoa" Programme for Centres of Excellence in R&D (SEV-2015-0522), the Obra Social "la Caixa" Foundation (LlumMedBcn) LASERLAB-EUROPE IV (EU-H2020 654148), "Fundació La Marató TV3" (201709.31), Marie Curie initial training network (OILTEBIA 317526), Societat Catalana de Pneumologia (SOCAP), and Sociedad Española de Neumología y Cirugía Torácica (SEPAR).In a pilot study on acute ischemic stroke (AIS) patients, unexpected periodic fluctuations in microvascular cerebral blood flow (CBF) had been observed. Motivated by the relative lack of information about the impact of the emergence of breathing disorders in association with stroke on cerebral hemodynamics, we hypothesized that these fluctuations are due to apneic and hypopneic events. A total of 28 patients were screened within the first week after stroke with a pulse oximeter. Five (18%) showed fluctuations of arterial blood oxygen saturation (=3%) and were included in the study. Near-infrared diffuse correlation spectroscopy (DCS) was utilized bilaterally to measure the frontal lobe CBF alongside respiratory polygraphy. Biphasic CBF fluctuations were observed with a bilateral increase of 27.1% 17.7% and 29.0% 17.4% for the ipsilesional and contralesional hemispheres, respectively, and a decrease of -19.3% 9.1% and -21.0% 8.9% for the ipsilesional and contralesional hemispheres, respectively. The polygraph revealed that, in general, the fluctuations were associated with apneic and hypopneic events. This study motivates us to investigate whether the impact of altered respiratory patterns on cerebral hemodynamics can be detrimental in AIS patients

    Kidins220 deficiency causes ventriculomegaly via SNX27-retromer-dependent AQP4 degradation

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    Several psychiatric, neurologic and neurodegenerative disorders present increased brain ventricles volume, being hydrocephalus the disease with the major manifestation of ventriculomegaly caused by the accumulation of high amounts of cerebrospinal fluid (CSF). The molecules and pathomechanisms underlying cerebral ventricular enlargement are widely unknown. Kinase D interacting substrate of 220 kDa (KIDINS220) gene has been recently associated with schizophrenia and with a novel syndrome characterized by spastic paraplegia, intellectual disability, nystagmus and obesity (SINO syndrome), diseases frequently occurring with ventriculomegaly. Here we show that Kidins220, a transmembrane protein effector of various key neuronal signalling pathways, is a critical regulator of CSF homeostasis. We observe that both KIDINS220 and the water channel aquaporin-4 (AQP4) are markedly downregulated at the ventricular ependymal lining of idiopathic normal pressure hydrocephalus (iNPH) patients. We also find that Kidins220 deficient mice develop ventriculomegaly accompanied by water dyshomeostasis and loss of AQP4 in the brain ventricular ependymal layer and astrocytes. Kidins220 is a known cargo of the SNX27-retromer, a complex that redirects endocytosed plasma membrane proteins (cargos) back to the cell surface, thus avoiding their targeting to lysosomes for degradation. Mechanistically, we show that AQP4 is a novel cargo of the SNX27-retromer and that Kidins220 deficiency promotes a striking and unexpected downregulation of the SNX27-retromer that results in AQP4 lysosomal degradation. Accordingly, SNX27 silencing decreases AQP4 levels in wild-type astrocytes whereas SNX27 overexpression restores AQP4 content in Kidins220 deficient astrocytes. Together our data suggest that the KIDINS220-SNX27-retromer-AQP4 pathway is involved in human ventriculomegaly and open novel therapeutic perspectives

    Desarrollo de la escala EDSOL para la detección de la soledad existencial en enfermos al final de la vida

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    Objetivo: Presentar el desarrollo de la escala de detección de la soledad existencial (EDSOL) en personas con enfermedades avanzadas en tratamiento paliativo. Método: Se describe el proceso de elaboración de la escala Detección de la Soledad Existencial EDSOL. Para ello, 1) se ha revisado la bibliografía existente sobre el tema; 2) se ha establecido un marco teórico de referencia; 3) se han definido los criterios que debía cumplir el instrumento de cribado; y 4) se ha consultado con expertos y enfermos la adecuación de los ítems de la escala. Resultados: Se presenta a la escala EDSOL, que consta de dos partes: 1) tres preguntas dirigidas a los enfermos; y 2) diferentes observaciones realizadas por el personal sanitario acerca de la presencia de signos externos de soledad existencial. La escala final fue revisada por enfermos y profesionales. Conclusión: La escala EDSOL es una herramienta apropiada para identificar la presencia de Soledad Existencial en pacientes al final de la vida. En este caso, se propondrá su uso sistemático en la detección temprana de la Soledad Existencial y la implementación de intervenciones asistenciales específicasAim: This paper presents the development of Detection of Existential Loneliness Scale (EDSOL) of patients with advanced disease/terminal illness that receiving palliative care. Method: The process of preparing the scale is described. For this: 1) the literature on the subject has been revised, 2)theoretical framework has been established, 3) it has been defined the criteria to be met by the screening tool, and 4) the final scale was reviewed by patients and experts. Results: The EDSOL scale consists of two parts: 1) three questions addressed to patients and; 2) several questions addressed to health staff about the observation of external signs of Existential Loneliness. The final scale was reviewed by patients and experts (facie validity) showing good validity. Conclussion: The EDSOL scale will be an appropriate tool for identifying the Existential Loneliness of patients at the end of life or advanced illness. In this case, we will propose the systematic use of EDSOL for early detection and specific interventions on existential loneliness experience

    Cost-effectiveness analysis of a multiple health behaviour change intervention in people aged between 45 and 75 years: a cluster randomized controlled trial in primary care (EIRA study)

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    Background: Multiple health behaviour change (MHBC) interventions that promote healthy lifestyles may be an efficient approach in the prevention or treatment of chronic diseases in primary care. This study aims to evaluate the cost-utility and cost-effectiveness of the health promotion EIRA intervention in terms of MHBC and cardiovascular reduction. Methods: An economic evaluation alongside a 12-month cluster-randomised (1:1) controlled trial conducted between 2017 and 2018 in 25 primary healthcare centres from seven Spanish regions. The study took societal and healthcare provider perspectives. Patients included were between 45 and 75 years old and had any two of these three behaviours: smoking, insufficient physical activity or low adherence to Mediterranean dietary pattern. Intervention duration was 12 months and combined three action levels (individual, group and community). MHBC, defined as a change in at least two health risk behaviours, and cardiovascular risk (expressed in % points) were the outcomes used to calculate incremental cost-effectiveness ratios (ICER). Quality-adjusted life-years (QALYs) were estimated and used to calculate incremental cost-utility ratios (ICUR). Missing data was imputed and bootstrapping with 1000 replications was used to handle uncertainty in the modelling results. Results: The study included 3062 participants. Intervention costs were €295 higher than usual care costs. Five per-cent additional patients in the intervention group did a MHBC compared to usual care patients. Differences in QALYS or cardiovascular risk between-group were close to 0 (- 0.01 and 0.04 respectively). The ICER was €5598 per extra health behaviour change in one patient and €6926 per one-point reduction in cardiovascular risk from a societal perspective. The cost-utility analysis showed that the intervention increased costs and has no effect, in terms of QALYs, compared to usual care from a societal perspective. Cost-utility planes showed high uncertainty surrounding the ICUR. Sensitivity analysis showed results in line with the main analysis. Conclusion: The efficiency of EIRA intervention cannot be fully established and its recommendation should be conditioned by results on medium-long term effects. Trial registration: Clinicaltrials.gov NCT03136211. Registered 02 May 2017 – Retrospectively registered © 2021, The Author(s)

    All-sky Search for High-Energy Neutrinos from Gravitational Wave Event GW170104 with the ANTARES Neutrino Telescope

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    Advanced LIGO detected a significant gravitational wave signal (GW170104) originating from the coalescence of two black holes during the second observation run on January 4th^{\textrm{th}}, 2017. An all-sky high-energy neutrino follow-up search has been made using data from the ANTARES neutrino telescope, including both upgoing and downgoing events in two separate analyses. No neutrino candidates were found within ±500\pm500 s around the GW event time nor any time clustering of events over an extended time window of ±3\pm3 months. The non-detection is used to constrain isotropic-equivalent high-energy neutrino emission from GW170104 to less than 4×1054\sim4\times 10^{54} erg for a E2E^{-2} spectrum

    The ANTARES Collaboration: Contributions to ICRC 2017 Part I: Neutrino astronomy (diffuse fluxes and point sources)

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    Papers on neutrino astronomy (diffuse fluxes and point sources, prepared for the 35th International Cosmic Ray Conference (ICRC 2017, Busan, South Korea) by the ANTARES Collaboratio
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