[en] A fast pattern recognition system for HEP experiments, based on artificial neural network algorithms (ANN), has been realized with standard electronics. The multiplicity and location of tracks in an event are determined in less than 75 ns. Hardware modules of this first level trigger were extensively tested for performance and reliability with data from the CPLEAR experiment. (orig.)

[en] In summary, a fascinating case is presented of an enormous 'blow-out' lesion in the left half of the mandible in a 17-year-old boy. The histological diagnosis was benign fibrous histiocytoma or non-ossifying fibroma. An extensive differential diagnosis was presented by the authors and although benign fibrous histiocytoma was their final diagnosis, they could not exclude an example of the rarely encountered entity called the Jaffe-Campanacci syndrome. This syndrome consists of multiple non-ossifying fibromas of the mandible, cafe-au-lait spots, various endocrine disorders, mental retardation, occular anomalies and cardiovascular malformations. (orig./SHA)

[en] The role of nuclear cardiology procedures in patients with suspected or known coronary artery disease lies in between clinical examination and left heart catheterization if diagnosis, prognosis or treatment effects are to be assessed. In other situations, these tests add important information to coronary angiography regarding functional significance of coronary artery stenoses and viability of involved myocardium. Based on results of several studies, patient groups can be identified in whom no further investigations are necessary after scintigraphic testing, whereas in other patients, non-invasive diagnostic testing may be omitted because coronary angiography is mandatory based on clinical findings. According to such considerations, diagnostic approaches to patients with coronary artery disease with and without previous myocardial infarction are proposed in this paper taking into account clinical assessment as well as non-invasive and invasive testing. (orig.)

[en] The superconducting energy gap Δ of the high temperature superconductor Bi₂Sr₂CaCu₂O₈ is determined using a home-built high vacuum low temperature scanning tunneling microscope. From numerically derived dI/dV spectra acquired at different locations on the surface gap values of Δ 31 ± 5 meV are obtained (Dynes fit). Other dI/dV curves show a V-shaped background suggesting a contamination layer present on the sample surface. (orig.)

[en] An artificial neural network classifier has been developed in order to separate on-line events containing a decaying neutral kaon. The proposed system performs better than classical selection methods in real-time applications. The biases due to the on-line selection are smaller than few per cent and are known. The system is robust against calibration variations and missing information. A hardware implementation of the algorithm allows an event selection in less than 40 μs and provides a considerable on-line rate reduction in tagged neutral kaon experiments. This classifier has been developed within the framework of the CPLEAR experiment. (orig.)

[en] A new first-level trigger for the L3 experiment at LEP (CERN) is presented. It uses the inner time expansion chamber of the detector, which is not until now used for triggering. The event selection presented here is based on identifying sectors containing genuine tracks originating from the interaction point. The system is capable of identifying both single tracks and hadronic jets in a sector. The sector identification used a neural network algorithm. The hardware for the event selection is built around the existing custom-made neural network digital modules. Events are classified in less than 100 ns and the final rate of accepted events is 1-3 Hz starting from a beam-crossing rate of 45 kHz. (orig.)

[en] In order to study the contribution of a possible colour Van der Waals potential to ²⁰⁸Pb-²⁰⁸Pb elastic scattering we discuss the influence of small additional potentials to the pure Coulomb interaction. The study shows, that - besides relativistic effects, vacuum polarisation and nuclear polarisability - the formation of quasimolecules during the scattering process gives the dominant contribution. Perfect agreement with the data would require a colour Van der Waals contribution, but the uncertainty in the quasimolecular effect is considerable. (orig.)

[en] Tensor analyzing powers A_xx and A_yy and vector analyzing powers A_y of the ¹H( vector d,pp)n breakup reaction at E_d=52.1 MeV were measured in the symmetric collinear and coplanar-star kinematic configurations. The experimental results are compared with rigorous three-nucleon continuum calculations using realistic nucleon-nucleon potentials. ((orig.))

[en] Pure and Li-containing amorphous hydrogenated carbon films were deposited using an ion beam deposition technique. Depending on Li content and deposition conditions, differences in chemical structure are detected. Samples were irradiated at room temperature with energetic oxygen ions of 100 eV to 1 keV. Transient time during which layers retain oxygen is significantly longer for Li-containing as compared to pure amorphous hydrogenated carbon films. Oxygen uptake is found to be mainly determined by Li content. For lower contents (c_Li<15 at.%) oxygen uptake is only about 12 at.%. For intermediate Li contents (15 at.%< c_Li<50 at.%) oxygen uptake increases and saturates above Li concentrations of about 30 at.%. In dependence on Li content, and chemical structure of the films, and irradiation conditions varying amounts of Li carbonate like, Li₂CO₃, and Li oxide like, Li₂O, compounds are detected in the irradiated samples. At room temperature about 35 at. % oxygen are retained at the surface of these films. For high initial Li contents (c_Li>50 at.%) carbon is almost completely removed upon irradiation and the resulting composition of the films is found to be close to the stoichiometry of Li oxide. (orig.)

[en] Described are two methods of evaluation of the uptake of ³⁰S by chondrosarcomas, i.e. autoradiography and external monitoring of the Bremsstrahlung. A higher concentration of sulfur in the tumor area of three patients was demonstrated after the injection of aliquots of both diagnostic and therapeutic activities. Apart from the simple handling and the quickly obtained results, the external monitoring of the Bremsstrahlung permits quantitative evaluation of the degree of uptake and a simple control over the progress of therapy. (orig.)