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T Weiland

Publications and source records attributed to T Weiland.

8 recordsLinked to original sources
PubMed2005

Impact of the displacement current on low-frequency electromagnetic fields computed using high-resolution anatomy models.

We present a comparison of simulated low-frequency electromagnetic fields in the human body, calculated by means of the electro-quasistatic formulation. The geometrical data in these simulations were provided by an anatomically realistic, high-resolution human body model, while the dielectric properties of the various body tissues were modelled by the parametric Cole-Cole equation. The model was examined under two different excitation sources and various spatial resolutions in a frequency range from 10 Hz to 1 MHz. An analysis of the differences in the computed fields resulting from a neglect of the permittivity was carried out. On this basis, an estimation of the impact of the displacement current on the simulated low-frequency electromagnetic fields in the human body is obtained.

Electric Conductivity↗
PubMed2005

[Ataxia].

Explore the source record for details and available documents.

Ataxia↗
PubMed2004

[Therapy of back pain: what is evidence-based?].

Back pain has to be classified by localisation, duration, and existence or absence of neurological deficits. Therapy mainly depends on the severity of neurological symptoms. The time period between the onset of symptoms and efficient therapy should be short in order to prevent the development of chronic pain. Therefore a sufficient, consistent and evidence-based conservative treatment should be initiated early on, with the only exception of special emergency situations as described further down in this article. Patients should not be immobilized, a better outcome is proven in patients who immediately continued practising their daily activities. First line medication consists of non-steroidal-anti-inflammatory-drugs (NSAID). If necessary, opioids and muscle-relaxants may be applied additionally. Surgical procedures are only indicated in a small number of patients. A sufficient data base with regard to the benefit of acupuncture, orthesis, and chiropractic medicine is lacking. Local injections should only be done in very special cases. Concerning chronic back pain a multimodal, multi-disciplinary pain treatment concept with physical training and behavioural therapy should be applied in order to teach the patient to avoid a passive and maladjusted attitude. Antidepressant drugs may also be indicated in chronic back pain.

Analgesics↗
PubMed2002

Generation of GW radiation pulses from a VUV free-electron laser operating in the femtosecond regime.

Experimental results are presented from vacuum-ultraviolet free-electron laser (FEL) operating in the self-amplified spontaneous emission (SASE) mode. The generation of ultrashort radiation pulses became possible due to specific tailoring of the bunch charge distribution. A complete characterization of the linear and nonlinear modes of the SASE FEL operation was performed. At saturation the FEL produces ultrashort pulses (30-100 fs FWHM) with a peak radiation power in the GW level and with full transverse coherence. The wavelength was tuned in the range of 95-105 nm.

Journal Article↗
PubMed1999

Anderson localization in a string of microwave cavities.

The field distributions and eigenfrequencies of a microwave resonator which is composed of 20 identical cells have been measured. With external screws the periodicity of the cavity can be perturbed arbitrarily. If the perturbation is increased a transition from extended to localized field distributions is observed. For very large perturbations the field distributions show signatures of Anderson localization, while for smaller perturbations the field distribution is extended or weakly localized. The localization length of a strongly localized field distribution can be varied by adjusting the penetration depth of the screws. Shifts in the frequency spectrum of the resonator provide further evidence for Anderson localization.

Journal Article↗
PubMed1992

[Prevalence of Borrelia burgdorferi antibodies in Hamburg blood donors].

One thousand regular blood donors of the Department of Transfusion Medicine at the University Hospital in Hamburg were screened for antibodies against the Lyme disease spirochete, B. burgdorferi. 7.2% were initially reactive in the enzyme immunoassay, 37.5% of which were confirmed by immunoblot. The seroprevalence of anti-B. burgdorferi antibodies thus is 2.7% in Hamburg blood donors. 25 of 27 positive donors received a physical exam, which did not reveal any symptoms of acute or chronic Lyme disease. 24 of these 25 donors were tested for B. burgdorferi-specific DNA in urine by polymerase chain reaction, which came out negative in all cases. Introduction of B. burgdorferi antibody screening is not regarded an effective means to prevent transfusion-transmitted Lyme disease.

Antibodies, Bacterial↗
PubMed1991

[Retrospective study of a borreliosis infected blood donor].

Lyme disease is caused by a spirochete, Borrelia burgdorferi, and represents a potential transfusion hazard. Some Borrelia burgdorferi-infected blood donors may not be disqualified by standard donor selection procedures, thus possibly transmitting the disease. In a follow-up of 14 recipients of blood products donated by such a donor, no clinical signs or serologic evidence of a transfusion-transmitted borreliosis could be demonstrated.

Adult↗