Andreas Heckel

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[1] Soil NOx emission from agricultural regions in the western United States has been investigated using satellite observations of NO2 from the SCIAMACHY instrument. We show that the SCIAMACHY observations over a 2 million hectare agricultural region in Montana capture the short intense NOx pulses following fertilizer application and subsequent(More)
PURPOSE To investigate the ability of diffusion-tensor imaging (DTI) and T2 to help detect the mildest nerve lesion conceivable, that is, subclinical ulnar neuropathy at the elbow. MATERIALS AND METHODS This prospective study was approved by the institutional ethics board. Written informed consent was obtained from all participants. Magnetic resonance(More)
Visual illusions are valuable tools for the scientific examination of the mechanisms underlying perception. In the peripheral drift illusion special drift patterns appear to move although they are static. During fixation small involuntary eye movements generate retinal image slips which need to be suppressed for stable perception. Here we show that the(More)
The MERIS and AATSR instruments onboard ENVISAT provide similar resolution and swath but complementary information, encompassing different spectral domains and viewing geometries. We present research on synergistic use of MERIS and AATSR imagery, with objectives (i) to define and evaluate algorithms for improved cloud screening, global aerosol retrieval and(More)
Producing a global and comprehensive description of atmospheric aerosols requires integration of ground-based, airborne, satellite and model datasets. Due to its complexity, aerosol monitoring requires the use of several data records with complementary information Remote Sens. 2016, 8, 421; doi:10.3390/rs8050421 Remote(More)
OBJECTIVE The aim of this study was to determine whether quantitative diffusion tensor imaging (DTI) adds diagnostic accuracy in magnetic resonance neurography. MATERIALS AND METHODS This prospective study was approved by the institutional review board. We enrolled 16 patients with peripheral polyneuropathy of various etiologies involving the upper arm(More)
PURPOSE To investigate the potential of diffusion tensor imaging (DTI) parameters as in-vivo biomarkers of axon and myelin sheath integrity of the median nerve in the carpal tunnel as validated by correlation with electrophysiology. METHODS MRI examinations at 3T including DTI were conducted on wrists in 30 healthy subjects. After manual segmentation of(More)
BACKGROUND Recent preclinical work strongly suggests that vagus nerve stimulation efficiently modulates nociception and pain processing in humans. Most recently, a medical device has offered a transcutaneous electrical stimulation of the auricular branch of the vagus nerve (t-VNS) without any surgery. OBJECTIVE Our study investigates whether t-VNS may(More)
The preferred structural pattern of antiparallel beta-barrels in proteins, described as the right-handed tilting of the peptide strands with respect to the axis of the barrel, is accounted for in terms of intra- and interchain interaction energies. It is related to the preference of beta-sheets for right-handed twisting. Conformational energy computations(More)