424 research outputs found

    Planar multilayer circuit quantum electrodynamics

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    Experimental quantum information processing with superconducting circuits is rapidly advancing, driven by innovation in two classes of devices, one involving planar micro-fabricated (2D) resonators, and the other involving machined three-dimensional (3D) cavities. We demonstrate that circuit quantum electrodynamics can be implemented in a multilayer superconducting structure that combines 2D and 3D advantages. We employ standard micro-fabrication techniques to pattern each layer, and rely on a vacuum gap between the layers to store the electromagnetic energy. Planar qubits are lithographically defined as an aperture in a conducting boundary of the resonators. We demonstrate the aperture concept by implementing an integrated, two cavity-modes, one transmon-qubit system

    Optical spectroscopy of Be stars: peak separation of Balmer emission lines

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    The Be stars display variable optical emission lines originating in the circumstellar disc. Here we analyse high resolution spectroscopic observations of Be stars and the distance between the peaks of H-alpha, H-beta, and H-gamma emission lines (ΔVα\Delta V_\alpha, ΔVβ\Delta V_\beta, and ΔVγ\Delta V_\gamma respectively). Combining published data, spectra from the ELODIE archive (obtained in the period 1998 -- 2003) and Rozhen spectra (obtained 2015 -- 2023) of 93 Be stars, we find a set of relations connecting ΔVα\Delta V_\alpha, ΔVβ\Delta V_\beta and ΔVγ\Delta V_\gamma. They are effective for 30ΔVα50030 \le \Delta V_\alpha \le 500 km s1^{-1}, 80ΔVβ60080 \le \Delta V_\beta \le 600 km s1^{-1}, and 40ΔVγ30040 \le \Delta V_\gamma \le 300 km s1^{-1}. The new equations are in the form y=ax+by=ax + b and are valid for a wider velocity range than in previous studies.Comment: Astronomische Nachrichten (accepted

    A multimodal neuroprosthetic interface to record, modulate and classify electrophysiological biomarkers relevant to neuropsychiatric disorders

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    Most mental disorders, such as addictive diseases or schizophrenia, are characterized by impaired cognitive function and behavior control originating from disturbances within prefrontal neural networks. Their often chronic reoccurring nature and the lack of efficient therapies necessitate the development of new treatment strategies. Brain-computer interfaces, equipped with multiple sensing and stimulation abilities, offer a new toolbox whose suitability for diagnosis and therapy of mental disorders has not yet been explored. This study, therefore, aimed to develop a biocompatible and multimodal neuroprosthesis to measure and modulate prefrontal neurophysiological features of neuropsychiatric symptoms. We used a 3D-printing technology to rapidly prototype customized bioelectronic implants through robot-controlled deposition of soft silicones and a conductive platinum ink. We implanted the device epidurally above the medial prefrontal cortex of rats and obtained auditory event-related brain potentials in treatment-naïve animals, after alcohol administration and following neuromodulation through implant-driven electrical brain stimulation and cortical delivery of the anti-relapse medication naltrexone. Towards smart neuroprosthetic interfaces, we furthermore developed machine learning algorithms to autonomously classify treatment effects within the neural recordings. The neuroprosthesis successfully captured neural activity patterns reflecting intact stimulus processing and alcohol-induced neural depression. Moreover, implant-driven electrical and pharmacological stimulation enabled successful enhancement of neural activity. A machine learning approach based on stepwise linear discriminant analysis was able to deal with sparsity in the data and distinguished treatments with high accuracy. Our work demonstrates the feasibility of multimodal bioelectronic systems to monitor, modulate and identify healthy and affected brain states with potential use in a personalized and optimized therapy of neuropsychiatric disorders

    Accretion in the recurrent nova T CrB: Linking the superactive state to the predicted outburst

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    Context: T CrB (NOVA CrB 1946) is a famous recurrent nova with a recurrence timescale of 80 years. Aims: We aim to estimate the colours, luminosity, and mass-accretion rate for T CrB (NOVA CrB 1946) during and after the superactive state. Methods and Results: We performed and analysed UBVUBV photometry of the recurrent nova T~CrB. For the hot component of T~CrB, we find average dereddened colours of (UB)0=0.70±0.08(U-B)_0 = -0.70 \pm 0.08 and (BV)0=0.23±0.06(B-V)_0 = 0.23 \pm 0.06, which correspond to an effective temperature of 9400±5009400 \pm 500~K and an optical luminosity of 40110 L40-110~L_\odot during the superactive state (2016-2022). After the end of the superactive state, the hot component became significantly redder, (UB)00.3(U-B)_0 \approx -0.3 and (BV)00.6(B-V)_0 \approx 0.6 in August 2023, and its luminosity decreased markedly to 202520-25~LL_\odot in April-May 2023, and to 89 L8-9~L_\odot in August 2023. The total mass accreted during the superactive state from 2014 to 2023 is 2×107\sim 2 \times 10^{-7}~M_\odot. This is a significant fraction of the mass required to cause a thermonuclear runaway (TNR). Overall our results support a model in which a large accretion disc acts as a reservoir with increased accretion rate onto the central white dwarf during disc high states, ultimately leading to a TNR explosion, which now seems to be imminent.Comment: Astronomy & Astrophysics (accepted

    Self-esteem in adolescents

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    PURPOSE. Self-esteem is an overall evaluation of the person’s value, expressed in a positive or negative orientation towards himself. Its development starts from birth and is constantly changing under the influence of experience (1). Especially important is the role of self-esteem in the process of adolescence. During this period, it correlates with both academic achievement and mental health. The aim of this study is to analyze the correlation between academic achievement and self-esteem among teenagers. Forty 14-year-old students (20 boys and 20 girls) with excellent, very good and good results in school were examined. Methods: Self-Esteem Scale (RSE) (2). The study results show that girls have significantly more negative attitudes towards themselves (x = 32.25) comparing with boys (x = 25.14). These results support the need for further research to explore how individual and contextual factors affect the development of self-esteem over the school years

    Trait and state anxiety as factors of threshold and tolerance to experimentally induced pain

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    Pain is an experience that has physical, psychological and social aspects. Sensitivity to pain is individual and depends on psychological factors. Studies have shown that anxiety is associated with the perception of experimentally induced pain. PURPOSE: The purpose of the present study is to examine the relationship between anxiety, threshold and tolerance to experimentally induced pain in healthy persons. METHODS: 35 healthy persons at the age from 19 to 39, 20 women and 15 men were examined. Methods: Spielberger’s questionnaire, Cold pressor test, Visual Analog Scale for Pain, Descriptive statistics, Correlation analysis, Mann-Whitney’s Test. RESULTS: Significant differences in tolerance to pain were identified depending on the levels of state anxiety (U=12.5, Р=0.037). The state anxiety was greatly related to the intensity of the pain experienced. (Spearman rho=0.49, P=0.008). Significant differences were not found in threshold, tolerance and intensity of pain depending on the levels of trait anxiety in the examined people. CONCLUSIONS: The increased levels of state anxiety in healthy persons exposed to experimentally induced pain suggest a weaker endurance to pain and perceiving it as stronger
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