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Thomas Keller  - - - 
Top co-authors See all
David E. Cohen

245 shared publications

M. A. Lee

227 shared publications

Götz Geldner

160 shared publications

Clinic for Intensive Care, Emergency Medicine and Pain Therapy, Klinikum Ludwigsburg, Ludwigsburg, Germany

Christoph Gasche

113 shared publications

Department of Medicine 3, Medical University of Vienna, Austria

Lawrence Goldstein

108 shared publications

Resident Surgeon, and attending surgeon, respectively, Department of Surgery, University of California, Davis-East Bay, Oakland, CA, US

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Distribution of Articles published per year 
(1991 - 2018)
Total number of journals
published in
 
58
 
Publications See all
Article 1 Read 0 Citations Clinical Manifestation of Acute, Subacute, and Chronic Low Back Pain in Different Age Groups: Low Back Pain in 35,446 Pa... Philipp Hüllemann, Thomas Keller, Maria Kabelitz, Janne Gier... Published: 23 June 2018
Pain Practice, doi: 10.1111/papr.12704
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Background Low back pain is major health care problem causing tremendous economic cots. Methods Clinical manifestation of low back pain (LBP) was characterized in 35,446 patients. We focused on the comparison of the acute, subacute, and chronic LBP stage with regard to patients’ age, based on epidemiological and clinical questionnaires (e.g. painDETECT, pain disability index), pain intensity, pain descriptors, and functional impairment. Results We found that neuropathic components were most frequent in chronic LBP patients at the age of 51‐60 years. Elderly LBP patients showed a decrease in neuropathic and an increase of nociceptive pain. The most frequently reported pain descriptors were “pressure pain” and “pain attacks” through all stages of LBP, whereas “burning” and “prickling” were most frequent in the chronic stage. Patients after back surgery presented neuropathic pain symptoms most frequently and had the highest amount of pain medication intake. Conclusions Burning and prickling were revealed as possible indicators for LBP chronicity. Combined with pain attacks and pressure pain, these four pain descriptors might be a promising adjunct to pain intensity in terms of outcome parameters for future LBP studies. The decrease of neuropathic pain syndromes in the elderly might be explained by degenerative processes in main parts. The presented work provides important insights on LBP management in the acute, subacute, and chronic stage. This article is protected by copyright. All rights reserved.
Article 0 Reads 0 Citations Impact of suggestion on the human experimental model of cold hyperalgesia after topical application of high-concentratio... Stephanie Helfert, Maren Reimer, Lutz Barnscheid, Philipp Hü... Published: 11 June 2018
European Journal of Pain, doi: 10.1002/ejp.1240
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Background Human experimental pain models in healthy subjects offer unique possibilities to study mechanisms of pain within a defined setting of expected pain symptoms, signs and mechanisms. Previous trials in healthy subjects demonstrated that topical application of 40% menthol is suitable to induce cold hyperalgesia. The objective of this study was to evaluate the impact of suggestion on this experimental human pain model. Methods The study was performed within a single‐center, randomized, placebo controlled, double‐blind, 2 period cross‐over trial in a cohort of 16 healthy subjects. Subjects were tested twice after topical menthol application (40% dissolved in ethanol) and twice after ethanol (as placebo) application. In the style of a balanced placebo trial design, the subjects received during half of the testing the correct information about the applied substance (topical menthol or ethanol) and during half of the testing the incorrect information, leading to four tested conditions (treatment conditions: menthol‐told‐menthol and menthol‐told‐ethanol; placebo conditions: ethanol‐told‐menthol and ethanol‐told‐ethanol). Results Cold but not mechanical hyperalgesia was reliably induced by the model. The cold pain threshold decreased in both treatment conditions regardless whether true or false information were given. Minor suggestion effects were found in subjects with prior ethanol application. Conclusions The menthol model is a reliable, non‐suggestible model to induce cold hyperalgesia. Mechanical hyperalgesia is not as reliable to induce. This article is protected by copyright. All rights reserved.
Article 0 Reads 0 Citations Feedbacks between soil penetration resistance, root architecture and water uptake limit water accessibility and crop gro... Tino Colombi, Lorena Chagas Torres, Achim Walter, Thomas Kel... Published: 01 June 2018
Science of The Total Environment, doi: 10.1016/j.scitotenv.2018.01.129
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PROCEEDINGS-ARTICLE 5 Reads 0 Citations 144 Novel experimental design for two-dimensional delamination in fiber-reinforced polymer laminates Aida Cameselle-Molares, Anastasios P. Vassilopoulos, Thomas ... Published: 30 May 2018
Proceedings of The Eighteenth International Conference of Experimental Mechanics, doi: 10.3390/icem18-05283
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The two-dimensional (2D) delamination behavior of composite laminates under quasi-static out-of-plane opening loads has been experimentally investigated. A novel design and experimental set-up for fiber-reinforced polymer (FRP) laminated plates with a circular embedded pre-crack was developed. Increasing load-displacement curves were obtained due to the increasing crack front length during propagation. Throughout the loading process, stiffening and softening mechanisms were activated. The stretching of delaminated part of the laminates constituted the main stiffening mechanism. Once the crack started growing, a corresponding softening due to crack propagation occurred together with a secondary stiffening mechanism, fiber-bridging. These stiffness-related mechanisms were reflected in the compliance.
Article 0 Reads 0 Citations Generalized resolution matrix for neutron spin-echo three-axis spectrometers Felix Groitl, Thomas Keller, Klaus Habicht Published: 29 May 2018
Journal of Applied Crystallography, doi: 10.1107/s1600576718005307
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This article describes the energy resolution of spin-echo three-axis spectrometers (SE-TASs) by a compact matrix formalism. SE-TASs allow one to measure the line widths of elementary excitations in crystals, such as phonons and magnons, with an energy resolution in the µeV range. The resolution matrices derived here generalize prior work: (i) the formalism works for all crystal structures; (ii) spectrometer detuning effects are included; these arise typically from inaccurate knowledge of the excitation energy and group velocity; (iii) components of the gradient vector of the dispersion surface dω/dq perpendicular to the scattering plane are properly treated; (iv) the curvature of the dispersion surface is easily calculated in reciprocal units; (v) the formalism permits analysis of spin-echo signals resulting from multiple excitation modes within the three-axis spectrometer resolution ellipsoid.
Article 0 Reads 0 Citations Can within field yield variation be explained using horizontal penetrometer resistance and electrical conductivity measu... Elisabeth Bölenius, Johanna Wetterlind, Thomas Keller Published: 01 May 2018
Acta Agriculturae Scandinavica, Section B — Soil & Plant Science, doi: 10.1080/09064710.2018.1464201
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Spatial variations in yield occur in all agricultural fields to some degree. Knowledge of the reasons for these variations, especially temporally stable yield patterns, is needed in order to improve productivity by changing production methods or inputs. This information must be provided in a simple, cost-effective way. This study investigated whether field-scale measurements of penetration resistance (PR) could identify temporally stable yield patterns without complementary measurements of other properties. The PR measurements were also compared with field-scale apparent electrical conductivity (ECa) measurements and correlations between yield and PR and yield and ECa were investigated. Measurements with a newly constructed horizontal penetrometer and a non-invasive proximal electromagnetic induction sensor were carried out in three fields in east-central Sweden. The measurements were made once in each field, apart from one field where PR was measured twice in one season. The sensor measurements were compared with crop yield measured over the course of several years. The horizontal penetrometer was able to identify low-yielding areas in one field. However, single measurements of PR or ECa were insufficient to consistently identify yield variations. Parts of the fields showed more consistent patterns, with stronger correlations between PR, ECa and yield. PR and ECa data were better at explaining yield variations in drier years, but showed diverging patterns in different fields and neither showed a much stronger correlation to yield than the other. In future studies, simultaneous measurement of soil water content is recommended and also PR measurements at a water content drier than field capacity.