683 research outputs found

    The resistance anomaly in the surface layer of Bi2_2Sr2_2CaCu2_2O8+x_{8+x} single crystals under radio-frequency irradiation

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    We observed that radio-frequency (rf) irradiation significantly enhances the cc-axis resistance near and below the superconducting transition of the CuO2_{2} layer in contact with a normal-metal electrode on the surface of Bi2_{2}Sr2_{2}CaCu2_{2}O8+x_{8+x} single crystals. We attribute the resistance anomaly to the rf-induced charge-imbalance nonequilibrium effect in the surface CuO2_{2} layer. The relaxation of the charge-imbalance in this highly anisotropic system is impeded by the slow quasiparticle recombination rate, which results in the observed excessive resistance.Comment: 8 pages, 5 figure

    Managing Organizational Cyber Security – The Distinct Role of Internalized Responsibility

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    Desirable user behavior is key to cyber security in organizations. However, a comprehensive overview on how to manage user behavior effectively, in order to support organizational cyber security, is missing. Building on extant research to identify central components of organizational cyber security management and on a qualitative analysis based on 20 semi-structured interviews with users and IT-Managers of a European university, we present an integrated model on this issue. We contribute to understanding the interrelations of namely user awareness, user IT-capabilities, organizational IT, user behavior, and especially internalized responsibility and relation to organizational cyber security

    Opening the Black-Box of AI: Challenging Pattern Robustness and Improving Theorizing through Explainable AI Methods

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    Machine Learning (ML) algorithms, as approach to Artificial Intelligence (AI), show unprecedented analytical capabilities and tremendous potential for pattern detection in large data sets. Despite researchers showing great interest in these methodologies, ML remains largely underutilized, because the algorithms are a black-box, preventing the interpretation of learned models. Recent research on explainable artificial intelligence (XAI) sheds light on these models by allowing researchers to identify the main determinants of a prediction through post-hoc analyses. Thereby, XAI affords the opportunity to critically reflect on identified patterns, offering the opportunity to enhance decision making and theorizing based on these patterns. Based on two large and publicly available data sets, we show that different variables within the same data set can generate models with similar predictive accuracy. In exploring this issue, we develop guidelines and recommendations for the effective use of XAI in research and particularly for theorizing from identified patterns

    Ultrasonographic Findings of the Shoulder in Patients with Rheumatoid Arthritis and Comparison with Physical Examination

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    The objectives of this study were: 1) to identify the ultrasonographic (US) abnormalities and 2) to compare the findings of physical examination with US findings in rheumatoid arthritis (RA) patients with shoulder pain. We studied 30 RA patients. Physical examination was performed systemically as follows: 1) area of tenderness; 2) range of passive and active shoulder motion; 3) impingement tests; 4) maneuvers for determining the location of the tendon lesions. US investigations included the biceps, the supraspinatus, infraspinatus, and subscapularis tendons; the subacromial-subdeltoid bursa; and the glenohumeral and acromioclavicular joints. Thirty RA patients with 35 painful and 25 non-painful shoulders were examined. The range of motion affected the most by shoulder pain was abduction. The most frequent US finding of shoulder joint was effusion in the long head of the biceps tendon. Among the rotator cuff tendons, subscapularis was the most frequently involved. Tendon tear was also common among non-painful shoulders. Physical examination used for the diagnosis of shoulder pain had low sensitivity and specificity for detecting abnormalities in the rheumatoid shoulder joint. In conclusion, US abnormalities showed frequent tendon tears in our RA patients. Physical examination had low sensitivity and specificity for detecting rotator cuff tear in the rheumatoid shoulder joint

    Positive and negative incentive contrasts lead to relative value perception in ants

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    Humans usually assess things not according to their absolute value, but relative to reference points - a main tenant of Prospect Theory. For example, people rate a new salary relative to previous salaries and salaries of their peers, rather than absolute income. We demonstrate a similar effect in an insect: ants expecting to find low-quality food showed higher acceptance of medium-quality food than ants expecting medium quality, and vice versa for high expectations. Further experiments demonstrate that these contrast effects arise from cognitive rather than mere sensory or pre-cognitive perceptual causes. Social information gained inside the nest can also serve as a reference point: the quality of food received from other ants affected the perceived value of food found later. Value judgement is a key element in decision making, and thus relative value perception strongly influences which option is chosen and ultimately how all animals make decisions

    Critical Temperature Oscillations and Reentrant Superconductivity due to the FFLO like State in F/S/F Trilayers

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    Ferromagnet/Superconductor/Ferromagnet (F/S/F) trilayers, in which the establishing of a Fulde-Ferrell Larkin-Ovchinnikov (FFLO) like state leads to interference effects of the superconducting pairing wave function, form the core of the superconducting spin valve. The realization of strong critical temperature oscillations in such trilayers, as a function of the ferromagnetic layer thicknesses or, even more efficient, reentrant superconductivity, are the key condition to obtain a large spin valve effect, i.e. a large shift in the critical temperature. Both phenomena have been realized experimentally in the Cu 41 Ni 59 /Nb/Cu 41 Ni 59 trilayers investigated in the present work.Comment: 22 pages, 6 figure

    Vortex Motion Noise in Micrometre-Sized Thin Films of the Amorphous Nb0.7Ge0.3 Weak-Pinning Superconductor

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    We report high-resolution measurements of voltage (V) noise in the mixed state of micrometre-sized thin films of amorphous Nb0.7Ge0.3, which is a good representative of weak-pinning superconductors. There is a remarkable difference between the noise below and above the irreversibility field Birr. Below Birr, in the presence of measurable pinning, the noise at small applied currents resembles shot noise, and in the regime of flux flow at larger currents decreases with increasing voltage due to a progressive ordering of the vortex motion. At magnetic fields B between Birr and the upper critical field Bc2 flux flow is present already at vanishingly small currents. In this regime the noise scales with (1-B/Bc2)^2 V^2 and has a frequency (f) spectrum of 1/f type. We interpret this noise in terms of the properties of strongly driven depinned vortex systems at high vortex density.Comment: 8 pages, 5 figures, version accepted for publication in PR

    The Grizzly, September 28, 1993

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    The Quilt\u27s Arrival: To Remember • Dawleys Appointed Biology Co-Chairs • Russian President Yeltsin Dissolves Parliament • Model UN Seeks New Delegation • Billy Joel Rocks Philly • Javapalooza • Big Al Day Exposed • Fitness Forum • Freshman Primer • Letter: Faculty Members Point Out Error • Tutorial Program Strengthens Ursinus • Ursinus Perceived as Anti-Gay • UC Training Staff Saves the Day • Bear Pack Way Ahead Again • Football Holds Off Western Maryland • Scooter\u27s Dayhttps://digitalcommons.ursinus.edu/grizzlynews/1319/thumbnail.jp

    Mode of birth and risk of infection-related hospitalisation in childhood: A population cohort study of 7.17 million births from 4 high-income countries

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    BACKGROUND: The proportion of births via cesarean section (CS) varies worldwide and in many countries exceeds WHO-recommended rates. Long-term health outcomes for children born by CS are poorly understood, but limited data suggest that CS is associated with increased infection-related hospitalisation. We investigated the relationship between mode of birth and childhood infection-related hospitalisation in high-income countries with varying CS rates. METHODS AND FINDINGS: We conducted a multicountry population-based cohort study of all recorded singleton live births from January 1, 1996 to December 31, 2015 using record-linked birth and hospitalisation data from Denmark, Scotland, England, and Australia (New South Wales and Western Australia). Birth years within the date range varied by site, but data were available from at least 2001 to 2010 for each site. Mode of birth was categorised as vaginal or CS (emergency/elective). Infection-related hospitalisations (overall and by clinical type) occurring after the birth-related discharge date were identified in children until 5 years of age by primary/secondary International Classification of Diseases, 10th Revision (ICD-10) diagnosis codes. Analysis used Cox regression models, adjusting for maternal factors, birth parameters, and socioeconomic status, with results pooled using meta-analysis. In total, 7,174,787 live recorded births were included. Of these, 1,681,966 (23%, range by jurisdiction 17%-29%) were by CS, of which 727,755 (43%, range 38%-57%) were elective. A total of 1,502,537 offspring (21%) had at least 1 infection-related hospitalisation. Compared to vaginally born children, risk of infection was greater among CS-born children (hazard ratio (HR) from random effects model, HR 1.10, 95% confidence interval (CI) 1.09-1.12, p < 0.001). The risk was higher following both elective (HR 1.13, 95% CI 1.12-1.13, p < 0.001) and emergency CS (HR 1.09, 95% CI 1.06-1.12, p < 0.001). Increased risks persisted to 5 years and were highest for respiratory, gastrointestinal, and viral infections. Findings were comparable in prespecified subanalyses of children born to mothers at low obstetric risk and unchanged in sensitivity analyses. Limitations include site-specific and longitudinal variations in clinical practice and in the definition and availability of some data. Data on postnatal factors were not available. CONCLUSIONS: In this study, we observed a consistent association between birth by CS and infection-related hospitalisation in early childhood. Notwithstanding the limitations of observational data, the associations may reflect differences in early microbial exposure by mode of birth, which should be investigated by mechanistic studies. If our findings are confirmed, they could inform efforts to reduce elective CS rates that are not clinically indicated
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