Uwe Graichen

Karl Landsteiner University of Health Sciences | KL · Division Biostatistics and Data Science

Introduction Anti-Xa serves as a clinical surrogate for assessing the efficacy and bleeding risk in patients treated with enoxaparin for thromboembolic events. Evidence from the literature and empirical observations suggest that patients are underdosed in clinical practice to avoid bleeding complications. This study aimed to investigate such underd...

Signal transducer and activator of transcription 3 (STAT3) is frequently overexpressed in patients with acute myeloid leukemia (AML). STAT3 exists in two distinct alternatively spliced isoforms, the full-length isoform STAT3α and the C-terminally truncated isoform STAT3β. While STAT3α is predominantly described as an oncogenic driver, STAT3β has be...

Background Skeletal morbidity in patients with cancer has a major impact on the quality of life, and preserving bone health while improving outcomes is an important goal of modern antitumor treatment strategies. Despite their widespread use in early disease stages, the effects of immune checkpoint inhibitors (ICIs) on the skeleton are still poorly...

Background ‘Definite Neuroborreliosis (NB)’ is diagnosed with the presence of NB-specific symptoms, cerebrospinal fluid (CSF) pleocytosis and an elevated Borrelia Burgdorferi antibody index. However, some diagnostic uncertainties exist. The B-cell chemokine CXCL13 represents an emerging biomarker for the diagnosis and treatment of NB because its in...

Aims/Purpose: Phosphenes are light phenomena in the eye that have been studied since the 18th century. They can be evoked mechanically or by electrostimulation, for example. The perception of phosphenes and their threshold, the limit of phosphene perception, has been the subject of numerous studies. In this work, the dynamics of the threshold shift...

Evaluations of new dry, high-density EEG caps have only been performed so far with serial measurements and not with simultaneous (parallel) measurements. For a first comparison of gel-based and dry electrode performance in simultaneous high-density EEG measurements, we developed a new EEG cap comprising 64 gel-based and 64 dry electrodes and perfor...

Phase slips arise from state transitions of the coordinated activity of cortical neurons which can be extracted from the EEG data. The phase slip rates (PSRs) were studied from the high-density (256 channel) EEG data, sampled at 16.384 kHz, of five adult subjects during covert visual object naming tasks. Artifact-free data from 29 trials were avera...

SpharaPy is a Python implementation of a new approach for spatial harmonic analysis (SPHARA). SPHARA extends the classical spatial Fourier analysis to non-uniformly positioned samples on arbitrary surfaces in R3. The basis functions (BF) used by SPHARA are determined by the eigenanalysis of the discrete Laplace–Beltrami operator, which is defined o...

Purpose The purpose of this paper is to present a simulation study using a model of a new optically pumped magnetometer sensor for application in the field of magnetoencephalography. The effects of sensor distance and orientation on the measurement information and the sensitivity to neuronal sources are investigated. Further, this paper uses a comb...

Important requirements for the analysis of multichannel EEG data are efficient techniques for signal enhancement, signal decomposition, feature extraction, and dimensionality reduction. We propose a new approach for spatial harmonic analysis (SPHARA) that extends the classical spatial Fourier analysis to EEG sensors positioned non-uniformly on the...

We present a multi-level optimization method to schedule carriers for an electroplating production process. In our specific application, product carriers with individual processing requests may be available only shortly before their intended start. This limits the optimization time for creating a schedule to a few minutes or less. From the practica...

Conditioning is a very important factor to be considered when solving linear inverse problems. Many different measures of conditioning exist, but some of them are not always numerically stable or can indicate that the problem is ill-conditioned, even though in reality it is not. We theoretically consider and numerically compare four figures of meri...

Electroencephalography is an important diagnostic tool for functional investigations of the human brain. Recent EEG measurement technologies provide high numbers of electrodes and sampling rates, which results in a considerable quantity of data. For the analysis of this EEG data, efficient signal analysis and decomposition methods are essential. In...

The human brain possesses a highly structured surface. A quantitative examination of the cortical surface is of particular interest for many questions, e.g. the investigation the relation between the spatial frequencies of cortical surfaces and spatial frequencies within Electroencephalogram and the analysis of changes of the structure of the human...

PurposeTo determine the reproducibility of fluorescence lifetime imaging (FLIM) measurements in ophthalmology on the basis of an evaluation of fluorescence decay photon histograms. MethodsTo measure the fluorescence lifetime at the human fundus a modified Heidelberg Retina Angiograph was used. The endogenous fluorophores were excited by a diode las...

PurposeTo determine the reproducibility of fluorescence lifetime imaging (FLIM) measurements in ophthalmology on the basis of an evaluation of fluorescence decay photon histograms. MethodsTo measure the fluorescence lifetime at the human fundus a modified Heidelberg Retina Angiograph was used. The endogenous fluorophores were excited by a diode las...

Evoked and induced activities are two typical components in the EEG and MEG time series after a stimulation. While evoked activity is phase-locked to the stimulus, induced activity is not. Present analysis methods are able to detect non-phase-locked parts of the signal, however, they do not improve the signal-to-noise ratio (SNR) of these signal co...

Eine der Haupttodesursachen in den westlichen Ländern sind koronare Herzerkrankungen. Momentan ist die Röntgenangiographie Goldstandard bei der Beurteilung der Koronargefäße. Dieses invasive, röntgenbasierte Verfahren bedarf der Infrastruktur eines Herzkatheterlabors. Ultraschall gewinnt in der Kardiographie als bildgebendes Verfahren zunehmend an...

Mit TEE-Sonden ist es möglich, Ultraschallbildserien vom Herzen in sehr guter Qualität aufzunehmen. Aus diesen Bildserien kann man Volumendatensätze rekonstruieren. Diese Volumendaten sind, trotz Triggerung nach Herz- und Atemphase, von starken Bewegungsartefakten gestört, die aber reduziert werden können, wenn man die benachbarten Bilder der Serie...

Zusammenfassung. Bei der Beurteilung des Gesundheitszustandes des menschlichen Herzens ist der Zustand der Koronargef¨ a?e mit Durchmes-sern gr¨ o?er als 2 mm besonders wichtig. Goldstandard f¨ ur die Untersu-chung der Koronarien ist die R¨ ontgenangiographie, ein invasives Verfah-ren. Es wird ein nichtinvasives Verfahren vorgestellt, mit dem es m¨...

Zusammenfassung Im vorliegenden Artikel wird ein Volumerenderingverfah- ren vorgestellt, das für Visualisierung von stark gerichteten, röhrenförmigen Struk- turen konzipert ist. In einem Analyseschritt wird mit Hilfe von Strukturtensoren für jedes Voxel des Volumens ein Maß für Kohärenz (Ähnlichkeit mit einer Röh- re) ermittelt. In Abhängigkeit die...