191 research outputs found
A note on brain actuated spelling with the Berlin brain-computer interface
No full textBrain-Computer Interfaces (BCIs) are systems capable of decoding neural activity in real time, thereby allowing a computer application to be directly controlled by the brain. Since the characteristics of such direct brain-tocomputer interaction are limited in several aspects, one major challenge in BCI research is intelligent front-end design. Here we present the mental text entry application ‘Hex-o-Spell’ which incorporates principles of Human-Computer Interaction research into BCI feedback design. The system utilises the high visual display bandwidth to help compensate for the extremely limited control bandwidth which operates with only two mental states, where the timing of the state changes encodes most of the information. The display is visually appealing, and control is robust. The effectiveness and robustness of the interface was demonstrated at the CeBIT 2006 (world’s largest IT fair) where two subjects operated the mental text entry system at a speed of up to 7.6 char/min
Vorschlag zur Ionenoptik und zur kinematischen Anpassung an dem Magnetspektrographen BIG KARL
No full textFür den Magnetspektrographen BIG KARL wird der Einbau einer zusätzlichen Quadrupollinse vorgeschlagen. Damit ergibt sich die Möglichkeit einer teleskopischen Ionenoptik. Für zukünftige Experimente wird eine Standardeinstellung mit einer Ortsdispersion von 6.6 m und verschwindender Winkeldispersion vorgeschlagen. Das D/M Verhältnis (Dispersion/Magnification) beträgt 14.0 m, der maximale Raumwinkel liegt bei 3 msr. Der Energiebereich beträgt bei einer Fokalebenenlänge von 0.66 m 20%. Zur kinematischen Anpassung des Spektrographen wird die Fokalebene verschoben. Diese Verschiebung kann einfach und schnell für unterschiedliche K-Werte mit Hilfe einer Software-Korrektur realisiert werden, wenn routinemäßig zwei Ortsspektren in der Fokalebene aufgenommen werden. Damit kann zusätzlich für jedes Ereignis der aktuelle Streuwinkel mit relativ guter Auflösung bestimmt werden. Die Dispersionsanpassung ist von der kinematischen Anpassung des Magnetspektrographen vollständig entkoppelt
Experimental study of isospin mixing in ¹²C + n-->¹³C(T=3/2) and ¹⁶O + n-->¹⁷O(T=3/2)resonances
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Wirksamkeit von Biofeedback bei primärem Kopfschmerz – Eine randomisierte, kontrollierte Studie
No full textBackgroundBiofeedback-treatment for primary headache is highly recommended. Its expenses are mostly not or not completely covered by health funds, hindering the implementation in the care system. This randomized controlled study aimed at evaluating the efficacy of a biofeedback-treatment for primary headache in the outpatient care system all over Germany. MethodsThe participants were divided into a direct treatment-group (n=41) and a waiting control-group (n=29). The treatment was carried out for 8-11 sessions with vasoconstriction-/vasodilation training for migraine, with electromyography training for headache of the tension type (diagnosis according to the criteria of the International Headache Association). Headache characteristics (frequency, duration, intensity) were collected via headache-diary before, during and after the treatment and headache specific disability using the Pain Disability Index before and after the treatment. The waiting group stated additional information of the questionnaires about 3 months before and again ultimately before the start of the treatment. Measurement of the headache specific self-efficacy (Headache Management Self-efficacy Scale) took place every second session. For the collected parameters the effect sizes f(2)or r were computed before in comparison to after the treatment and comparing the treatment-group to the waiting-group. ResultsHeadache characteristics decreased during the time of the study significantly linearly with medium to strong effects (frequency f(2)=0.302, p<0.001, duration f(2)=0.186, p<0.001, mean intensity f(2)=0.502, p<0.001, maximal intensity f(2)=0.546, p<0.001). Using biofeedback the self-efficacy rose significantly (p<0.001, r=0.782), even compared to the waiting time (p<0.001, r=0.604). Additionally the handling of pain, the psychological disability and the disability in everyday life improved significantly. Discussion and ConclusionOverall the effects were comparable to already existing studies. Therefore biofeedback turned out to be efficient against migraine and tension-type headache in the out-patient care setting. By that a better integration in the care system seems to be qualified
Producing long-lived 2(3) S positronium via 3(3) P laser excitation in magnetic and electric fields
No full textProducing positronium (Ps) in the metastable 2^3 S state is of interest for various applications in fundamental physics. We report here on an experiment in which Ps atoms are produced in this long-lived state by spontaneous radiative decay of Ps excited to the 3^3 P level manifold. The Ps cloud excitation is obtained with a UV laser pulse in an experimental vacuum chamber in presence of guiding magnetic eld of 25 mT and an average electric eld of 300 V cm^-1. The evidence of the 2^3 S state production is obtained to the 3.6 sigma level of statistical signicance using a novel analysis technique of the single-shot positronium annihilation lifetime spectra. The dynamic of the Ps population on the involved levels has been studied with a rate equation model
High resolution resonance study of the ¹²C+n total cross section in the region of ¹³C T=3/2 states
No full textPsychological comorbidities in osteoarthritis in Germany
No full textOsteoarthritis is a degenerative joint disease associated with pain, loss of function and reduced quality of life. Concomitant psychological disorders can significantly influence treatment outcomes. Therefore, we aimed to answer the following research questions: (1) How has the incidence of primary coxarthrosis and gonarthrosis developed over the last decade? (2) How high is the prevalence of osteoarthritis patients with concomitant psychological diagnoses? (3) Which psychological comorbidities are most prevalent in coxarthrosis and gonarthrosis patients, respectively? For this cross-sectional study, a dataset provided by the Federal Statistical Office (Destatis) consisting of annual, Germany-wide ICD-10 diagnosis codes from 2009 to 2019 was analysed. Incidences of the codes "M16.1" and "M17.1", unilateral primary coxarthrosis and unilateral primary gonarthrosis, were quantified. Prevalence rates of secondary diagnoses of the chapter F of the ICD-10 were determined. Incidences were 230.7/100,000 inhabitants for coxarthrosis and 224.2/100,000 inhabitants for gonarthrosis. Patients with psychological comorbidities constituted 9.0% of coxarthrosis cases and 8.9% of gonarthrosis cases, respectively. Between 2009 through 2019, the proportion of patients with a concomitant "F" diagnoses of the ICD-10 increased by + 37.8% for coxarthrosis and by 17.9% for gonarthrosis. The most prevalent secondary diagnoses were affective disorders (F3), whereby numbers increased over the years. Increasing psychological comorbidities advocate for the implementation of screening tools, prevention strategies, interdisciplinary approaches and psychological support in the treatment of osteoarthritis
Signal segmentation and denoising algorithm based on energy optimisation
No full textA nonlinear functional is considered in this short communication for time interval segmentation and noise reduction of signals. An efficient algorithm that exploits the signal geometrical properties is proposed to optimise the nonlinear functional for signal smoothing. Discontinuities separating consecutive time intervals of the original signal are initially detected by measuring the curvature and arc length of the smoothed signal. The nonlinear functional is then optimised for each time interval to achieve noise reduction of the original noisy signal. This algorithm exhibits robustness for signals characterised by very low signal to noise ratios
Resonance production and pi pi S-wave in pi(-) + p -> pi(-) pi(-) pi(+) + p(recoil) at 190 GeV/c
No full textThe COMPASS collaboration has collected the currently largest data set on diffractively produced pi(-) pi(-) pi(+) final states using a negative pion beam of 190 GeV/c momentum impinging on a stationary proton target. This data set allows for a systematic partial-wave analysis in 100 bins of three-pion mass, 0.5 < m(3 pi) < 2.5 GeV/c(2), and in 11 bins of the reduced four-momentum transfer squared, 0.1 < t' < 1.0 (GeV/c)(2). This two-dimensional analysis offers sensitivity to genuine one-step resonance production, i.e. the production of a state followed by its decay, as well as to more complex dynamical effects in nonresonant 3 pi production. In this paper, we present detailed studies on selected 3p partial waves with J(PC) = 0(-+) ,1(++) ,2(-+) ,2(++) ,and 4(++). In these waves, we observe the well-known groundstate mesons as well as a new narrow axial-vector meson a(1)(1420) decaying into f(0) (980)pi. In addition, we present the results of a novel method to extract the amplitude of the pi(-)pi(+) subsystem with I(G)J(PC) = 0(+)0(++) in various partial waves from the pi(-)pi(-)pi(+) data. Evidence is found for correlation of the f (0)(980) and f(0)(1500) appearing as intermediate pi(-)pi(+) isobars in the decay of the known pi(1800) and pi(2)(1880)
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