Background: Sitting is known to be bad for your cardiovascular health. We furthermore hypothesized that sitting posture will reduce perfusion of the foot and increase edema, possibly predisposing to disease like osteochondritis.
Methods: We included 27 healthy volunteers and performed MRI measurements including arterial spin labelling (ASL) and intravoxel incoherent motion (IVIM) perfusion as well as short tau inversion recovery (STIR) edema measurement and 3D volumetry.
The diagnostics of X-ray beam properties has a critical importance at the European X-ray Free-Electron Laser facility. Besides existing diagnostic components, utilization of a diamond sensor was proposed to achieve radiation-hard, non-invasive beam position and pulse energy measurements for hard X-rays. In particular, with very hard X-rays, diamond-based sensors become a useful complement to gas-based devices which lose sensitivity due to significantly reduced gas cross-sections.
View Article and Find Full Text PDFBackground: Good sleep is correlated with health. Primary insomnia is a common reason for consulting a primary care physician. It is usually treated with drugs despite clear evidence for the efficacy of behavioral therapy.
View Article and Find Full Text PDFThe development and characterization of an angle-resolved photoelectron spectrometer, based on the electron time-of-flight concept, for hard x-ray photon diagnostics at the European Free-Electron Laser, are described. The instrument is meant to provide users and operators with pulse-resolved, non-invasive spectral distribution diagnostics, which in the hard x-ray regime is a challenge due to the poor cross-section and high kinetic energy of photoelectrons for the available target gases. We report on the performances of this instrument as obtained using hard x-rays at the PETRA III synchrotron at DESY in multibunch mode.
View Article and Find Full Text PDFThe European X-ray Free-Electron Laser Facility in Germany delivers x-ray pulses with femtosecond pulse duration at a repetition rate of up to 4.5 MHz. The free-electron laser radiation is created by the self-amplified spontaneous emission (SASE) process, whose stochastic nature gives rise to shot-to-shot fluctuations in most beam properties, including spectrum, pulse energy, spatial profile, wavefront, and temporal profile.
View Article and Find Full Text PDFPurpose: Sudden unilateral peripheral vestibular deficit is mostly termed vestibular neuritis (VN), even if its cause or the exact location of the lesion remains unclear. Thus, therapy is mostly symptomatic. We aimed to prove if there is peripheral atrophy after VN with persistent canal paresis.
View Article and Find Full Text PDFJ Synchrotron Radiat
September 2019
X-ray photon beam diagnostic imagers are located at 24 positions in the European XFEL beam transport system to characterize the X-ray beam properties, and to give feedback for tuning and optimization of the electron acceleration and orbit, the undulators, and the X-ray optics. One year of commissioning allowed experience to be gained with these imagers, which will be reported here. The sensitive Spontaneous Radiation imager is useful for various investigations in spontaneous radiation mode: for undulator adjustments and for low-signal imaging applications.
View Article and Find Full Text PDFThe European X-ray Free-Electron Laser (European XFEL) (Altarelli et al., 2006; Tschentscher et al., 2017), the world's largest and brightest X-ray free-electron laser (Saldin et al.
View Article and Find Full Text PDFJ Synchrotron Radiat
September 2019
Detectors based on microchannel plates (MCPs) are used to detect radiation from free-electron lasers. Three MCP detectors have been developed by JINR for the European XFEL (SASE1, SASE2 and SASE3 lines). These detectors are designed to operate in a wide dynamic range from the level of spontaneous emission to the SASE saturation level (between a few nJ up to 25 mJ), in a wide wavelength range from 0.
View Article and Find Full Text PDFX-ray gas monitors (XGMs) are operated at the European XFEL for non-invasive single-shot pulse energy measurements and average beam position monitoring. They are used for tuning and maintaining the self-amplified spontaneous emission (SASE) operation and for sorting single-shot experimental data according to the pulse-resolved energy monitor data. The XGMs were developed at DESY based on the specific requirements for the European XFEL.
View Article and Find Full Text PDFHard X-ray free-electron lasers (XFELs) generate intense coherent X-ray beams by passing electrons through undulators, i.e. very long periodic magnet structures, which extend over hundreds of meters.
View Article and Find Full Text PDFCommissioning and first operation of an angle-resolved photoelectron spectrometer for non-invasive shot-to-shot diagnostics at the European XFEL soft X-ray beamline are described. The objective with the instrument is to provide the users and operators with reliable pulse-resolved information regarding photon energy and polarization that opens up a variety of applications for novel experiments but also hardware optimization.
View Article and Find Full Text PDFObjective: Angulated projections are used in radiography to show the cervical neural foramen. Imaging the coronal oblique planes in an MRI of the cervical spine should therefore improve visualization of neural foramen pathology. This has to be demonstrated.
View Article and Find Full Text PDFSolid-state ionization chambers are presented based on thin diamond crystals that allow pulse-resolved intensity measurements at a hard X-ray free-electron laser (FEL), up to the 4.5 MHz repetition rate that will become available at the European XFEL. Due to the small X-ray absorption of diamond the thin detectors are semi-transparent which eases their use as non-invasive monitoring devices in the beam.
View Article and Find Full Text PDFJ Neurol Surg A Cent Eur Neurosurg
January 2016
Intramuscular or infiltrating lipomas are rare. We present a 58-year-old man with an intramuscular lipoma developing after decompression surgery for lumbar spinal canal stenosis. One year after macroscopically complete lipoma resection, an even bigger recurrent tumor had to be removed.
View Article and Find Full Text PDFObjective: To determine the effectiveness of cervical transforaminal injection of steroids (CTFIS) and to explore possible determinants of response in patients with cervical disc herniation.
Design: Retrospective practice audit covering a time period of 6 months.
Setting: Single spine center in which the patients underwent CTFIS, surgery, and subsequent treatment.
Background: During the 4,487 km ultra marathon TransEurope-FootRace 2009 (TEFR09), runners showed catabolism with considerable reduction of body weight as well as reversible brain volume reduction. We hypothesized that ultra marathon athletes might have developed changes to grey matter (GM) brain morphology due to the burden of extreme physical training. Using voxel-based morphometry (VBM) we undertook a cross sectional study and two longitudinal studies.
View Article and Find Full Text PDFIntroduction: Susceptibility to pain varies among individuals and may predispose to a higher risk for pain disorders. Thus, it is of interest to investigate subjects who exhibit higher resistance to pain. We therefore tested pain tolerance and assessed personality traits of ultra-marathon athletes who are able to run 4487 km (2789 mi) over 64 days without resting days and compare the results to controls.
View Article and Find Full Text PDFBackground: During the extremely challenging 4,487 km ultramarathon TransEurope-FootRace 2009, runners showed considerable reduction of body weight. The effects of this endurance run on brain volume changes but also possible formation of brain edema or new lesions were explored by repeated magnetic resonance imaging (MRI) studies.
Methods: A total of 15 runners signed an informed consent to participate in this study of planned brain scans before, twice during, and about 8 months after the race.