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In this comparative study, a solid composite, AN/HTPB-based propellant was prepared by conventional processing in a mechanical mixer and by applying an advanced processing technique relying on resonant acoustic mixing (RAM). After curing of the propellants, cross-sections were prepared and characterized by scanning electron microscopy. Also the density of the propellants was measured and finally the ballistic properties were measured using chimney burner tests. The experimental results clearly showed that the oxidizer particles, the homogeneity of the propellants, the density and the burn rate properties are hardly affected by the processing method. For the propellant studied in this research, resonant acoustic mixing is a very promising, advanced processing technique that can be applied as an alternative to the conventional mechanical mixing of this high solid load propellant composition. © 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim

Contains fulltext : 36387.pdf ( ) (Open Access) Contains fulltext : 36387.pdf (Publisher’s version ) (Open Access) Aims.The capability of radio antenna arrays to measure cosmic ray air showers with very large zenith angles is explored. This is important, since a possible neutrino detection has to fulfill two requirements. First: antennas should be able to detect very inclined cosmic ray air showers, and second: it should be possible to estimate the distance to the shower maximum, since neutrinos are most likely to travel far through the Earth's atmosphere without interaction and induce air showers close to the ground. Methods: LOPES (LOFAR PrototypE Station; LOFAR - LOw Frequency ARray), an array of dipole antennas, is used for the detection of inclined cosmic ray air showers. LOPES is co-located and triggered by the KASCADE (KArlsruhe Shower Core and Array DEtector) experiment, which also provides information on air shower properties such as electron and muon numbers on the ground, as well as the arrival direction. Radio emission of nearly vertical cosmic ray air showers has been detected by LOPES. Results: LOPES-10 (the first phase of LOPES, consisting of 10 antennas) detected a significant number of cosmic ray air showers with a zenith angle larger than 50°, and many of these have very high radio field strengths. The most inclined event that has been detected with LOPES-10 has a zenith angle of almost 80°. This is proof that the new technique is also applicable for cosmic ray air showers with high inclinations, which in the case that they are initiated close to the ground, can be a signature of neutrino events. Conclusions: .Our results indicate that arrays of simple radio antennas can be used for the detection of highly inclined air showers, which might be triggered by neutrinos. In addition, we found that the radio pulse height (normalized with the muon number) for highly inclined events increases with the geomagnetic angle, which confirms the geomagnetic origin of radio emission in cosmic ray air showers.

The flux of cosmic-ray induced single hadrons near sea level has been measured with the large hadron calorimeter of the KASCADE experiment. The measurement corroborates former results obtained with detectors of smaller size if the enlarged veto of the 304 m^2 calorimeter surface is encounted for. The program CORSIKA/QGSJET is used to compute the cosmic-ray flux above the atmosphere. Between E_0=300 GeV and 1 PeV the primary proton spectrum can be described with a power law parametrized as dJ/dE_0=(0.15+-0.03)*E_0^{-2.78+-0.03} m^-2 s^-1 sr^-1 TeV^-1. In the TeV region the proton flux compares well with the results from recent measurements of direct experiments.

Mit Hilfe des Strangpresverfahrens lassen sich durch die Einlagerung von plattchenformigen Teilchen aus hochfesten und hochmoduligen Werkstoffen in die zu verpressende Glasschmelze Verbundstabe mit im Vergleich zum unverstarkten Glas erhohtem Elastizitatsmodul und gesteigerter Festigkeit erzeugen. Diese Verbesserung der mechanischen Eigenschaften ruhrt in erster Linie von der Ausrichtung der Plattchen her, die durch die laminare Scherstromung der hochviskosen Glasschmelze in der Umformzone und im Matrizenkanal bewirkt wird. Um statistische Aussagen uber die Plattchenorientierung innerhalb des extrudierten Verbundstranges zu erhalten, werden neben experimentellen auch bevorzugt theoretische Untersuchungsmethoden angewandt. Durch die systematische Variation der einzelnen Strangpresparameter last sich auf diese Weise eine zielgerichtete Optimierung des Herstellungsprozesses bezuglich der Verstarkungswirkung der eingelagerten Partikel erzielen. Zu diesem Zweck wird ein Modell vorgestellt, welches ausgehend von einem mit Hilfe der Methode der Finiten Elemente berechneten Geschwindigkeitsprofil der Extrusionsstromung die Bewegung der Plattchen wahrend des Umformvorganges simuliert. Die gegenseitige Beeinflussung der Verstarkungskomponenten wird dabei durch die Einfuhrung eines Interaktionskoeffizienten berucksichtigt. Im einzelnen wird das Ausrichtungsverhalten der Einlagerungspartikel an Modellen mit unterschiedlichen Randbedingungen in Abhangigkeit der Geometrie und des Volumenanteils der Verstarkungskomponenten untersucht. Die daraus gewonnen theoretischen Ergebnisse werden anschliesend den an extrudierten Verbundstaben mit Hilfe der automatischen Bildanalyse ermittelten experimentellen Werten gegenubergestellt. Dieser Vergleich belegt die Eignung des vorgestellten Simulationsmodells. Theoretical and Experimental Analysis of the Orientation-Behaviour of Reinforcing Platelet-Components during the Extrusion of Composites with a Glass-Matrix By embedding platelets consisting of materials with high modulus of elasticity and strength in the extruded glass-melt, composites with increased Young's modulus and strength compared to non-reinforced glass can be produced. This improvement of the mechanical properties is primarily caused by the orientation of the platelets, which is a result of the laminar shear-flow of the highly viscous glass-melt within the deformation zone and within the die channel. To acquire statistical statements about the plateletorientation within the extruded compound rods theoretical research methods are preferentially employed over experimental ones. By the systematic variation of individual extrusion-parameters a systematic optimization of the manufacturing process concerning the reinforcing effect of the embedded particles is made possible. To this end a model has been developed, which simulates the motion of the platelets during the deformation process based on a finite-element computed velocity profile development of the extrusion flow. The interaction between the reinforcing particles is considered by using an interaction coefficient. In detail the orientation-behaviour of the embedded particles is analyzed as a function of their geometry and volume ratio in models with variable boundary conditions. Subsequently the theoretical results, obtained with these calculations, are set against the experimental results, which were determined on extruded composites with the aid of an automatic image-analyzing system. This comparison documents the suitability of the presented simulation-model.

Die Einlagerung von Kurzfasern in anorganische Glaser ermoglicht bekanntlich eine erhebliche Steigerung der Festigkeit sowieder Bruchzahigkeit dieser Werkstoffe. Noch unerforscht ist der Einflus der Faserverstarkung auf die mechanische Dampfung der Verbunde. Im vorliegenden Aufsatz wird die dynamisch-mechanisch-ther-mische Analyse vorgestellt, mit deren Hilfe die mechanische Dampfung und Elastizitat von unverstarktem und unidirektional SiC-Kurzfaserverstarktem AR-Glas in Abhangigkeit von Temperatur und Faservolumengehalt untersucht wurden. Die Ergebnisse zeigen, das die Verbundproben zusatzlich zu einer glastypischen Temperaturabhangigkeit der Dampfung einen auf die Faserver-starkung zuruckfuhrbaren Dampfungsanteil aufweisen. Dieser Dampfungsanteil ist wie auch die Probenelastizitat in hohem Mase vom Faservolumengehalt abhangig und wird hauptsachlich auf Gleitvorgange in der Faser-Matrix-Grenzflache unter der schwingenden Belastung zuruckgefuhrt. Bei Proben mit einem Faservolumengehalt von 10% und einer Temperatur von 15°C wird eine gegenuber unverstarktem AR-Glas um rund 100% gesteigerte Dampfung bei einem um etwa 50% geringeren absoluten Elastizitatsmodul beobachtet. Elasticity and mechanical damping of an unidirectional SiC-short-fibre reinforced alkali-lime-silicate-glass The embedment of short-fibres in inorganic glasses enables as is well know a considerable improvement of the strength as well as the fracture toughness of these materials. Still not investigated is the influence of the fibre-reinforcement on the mechanical damping of the composites. In this paper the dynamic mechanical thermal analysis is presented, which was used to determine mechanical damping and elasticity of not reinforced and unidirectional SiC-short-fibre reinforced AR-glass as a function of temperature and fibre volume fraction. The results show that the composite specimens exhibit - besides a glass-typical temperature dependence of the damping - an additional damping part, which can be attributed to the fibre reinforcement. This damping part is just as the specimen elasticity to a large extent dependent on the fibre volume fraction and is mainly associated with sliding processes in the fibre-matrix-interface under the vibrating stress. Specimens with a fibre volume fraction of 10% and a temperature of 15°C show-in comparison to non-reinforced AR-glass - an about 100% increased damping value connected with a nearly 50% decreased Youngs modulus.

Die vorliegenden Untersuchungen charakterisieren die mechanischen Eigenschaften verschiedener kohlenstoffaserverstarkter Epoxide unter quasistatischer Beanspruchung, wobei neben Prepregs auch Naslaminate berucksichtigt wurden. Die Prufungen dienten zur Ermittlung einer geeigneten Faser/Matrix-Kombination fur den Einsatz bei tiefen Temperaturen, weshalb sie sowohl bei Raumtemperatur als auch in flussiger Stickstoffatmosphare ausgefuhrt wurden. Als Bewertungskriterien der Werkstoffe wurden die Kenngrosen Bruchfestigkeit, Bruchdehnung und Elastizitatsmodul herangezogen. Im Zugversuch nehmen die beiden erstgenannten Kennwerte mit sinkender Temperatur erwartungsgemas tendenziell ab, wohingegen der Elastizitatsmodul geringfugig ansteigt. Im Druckversuch dagegen steigen alle genannten Kennwerte an. Weiterhin ist ein unterschiedlich stark ausgepragter Einflus der Pruftemperatur auf die mechanischen Kenngrosen der Prepregsysteme und der Naslaminate erkennbar. Schlieslich zeigen die Versuche, das die Temperaturabhangigkeit der genannten mechanischen Eigenschaften durch die Wahl der eingelagerten Verstarkungsfasern beeinflust werden kann. Diese Aussage trifft in besonderem Mase auf die maximal erreichbare interlaminare Scherfestigkeit zu.

Faserverbundwerkstoffe sind durch ein anisotropes Verhalten bezuglich ihrer mechanischen Eigenschaften gekennzeichnet, welches durch die Ausrichtung der eingelagerten Fasern verursacht und bei Kurzfaser-Verbunden in starkem Mase von den Fliesvorgangen wahrend des Umformprozesses beeinflust wird. Um Aussagen uber die Orientierung der Verstarkungsfasern am Ende des Herstellungsprozesses zu erhalten und diesen hinsichtlich verbesserter Werkstoffeigenschaften zu optimieren, werden bevorzugt numerische Simulationsverfahren eingesetzt. Hierzu wird ein Modell vorgestellt, welches ausgehend von einer dreidimensionalen Finite-Elemente-Berechnung des Stromungszustandes im Fliesgebiet die Bewegung der Kurzfasern wahrend der Herstellung simuliert. Dabei wird die gegenseitige Beeinflussung der einzelnen Fasern durch die Berucksichtigung eines Interaktionskoeffizienten beschrieben. Am Beispiel des Strangpressens kurzfaserverstarkter Glaser wird die Faserausrichtung an Modellen mit unterschiedlichen Presraumgeometrien und variierten Randbedingungen ermittelt. Diese erlauben es, den Einflus der Prozesparameter auf die zu erwartende Verbundqualitat zu bestimmen. Das vorgestellte Simulationsmodell Last sich daruber hinaus auch auf andere komplexe Umform- und Stromungsvorgange zur Herstellung faserverstarkter Werkstoffe anwenden. Numerical Simulation of the Fibre-Motion during the Extrusion of Short-Fibre-Reinforced Glass-Melts Fibre-reinforced materials are characterized by an anisotropic behaviour of the mechanical properties, which is caused by the alignment of the embedded fibres. In the case of short-fibre-compounds this behaviour is strongly influenced by the mechanism of flow during the manufacturing process. Numerical simulation Methods are preferentially used to get informations about the orientation of the reinforced fibres at the end of the molding-process and to improve the properties of the compound. For that, a model is developed, which calculates the motion of the short-fibres in the area of flow, basing on a three-dimensional finite-element-computation. Thereby the interaction between the Particular fibres during the orientation process is considered by using an interaction coefficient. Examplified at the extrusion of short fibre reinforced glass-melts, the fibre orientation is determined at models with different geometries of the pressing tool and variable boundary conditions. This procedure allows to determine the influence of the process-parameters On the expected quality of the composite. The represented simulation-model can also be used for other molding- and extrusion-processes of fibre reinforced materials.

Previous EAS investigations have shown that for a fixed primary energy the charged particle density becomes independent of the primary mass at certain (fixed) distances from the shower axis. This feature can be used as an estima- tor for the primary energy. We present results on the recon- struction of the primary energy spectrum of cosmic rays from the experimentally recorded S(500) observable (the density of charged particles at a distance of 500 m to the shower core as measured in a plane normal to the shower axis) using the KASCADE-Grande detector array. The KASCADE-Grande experiment is hosted by the Karlsruhe Institute for Technol- ogy - Campus North, Karlsruhe, Germany, 110 m a.s.l. and

The flow behaviour of a glass melt during the co-extrusion of glass rods reinforced with long fibres is simulated with the aid of a finite-element program developed specially, to gain a better understanding of the flow in the shaping zone of the block container for optimization of the manufacturing parameters. The mathematical investigation of the flow and its graphical description by the corresponding directional field for the local velocities, establish that a die material with good wall-slipping behaviour is especially convenient. The calculation also supplies statements concerning the most favourable geometrical dimensions for the deformation zone.

The KASCADE-Grande experiment measures extensive air showers induced by primary cosmic rays in the energy range 1014 – 1018 eV. The major motivation for KASCADE-Grande is the investigation of the so called ”knee” in the energy spectrum of cosmic rays and its presumed rigidity dependence. A short overview of the experimental setup with focus on the Grande array and its new data acquisition system is given. As an example of analysis the reconstruction of the total muon number is presented.

KASCADE‐Grande, an extension of the former KASCADE experiment, is a multi‐component Extensive Air Shower (EAS) experiment located in Karlsruhe Institute of Technology (Campus North), Germany. An important observable for analyzing the EAS is the lateral density of charged particles in the intrinsic shower plane. This observable is deduced from the basic information provided by the Grande scintillators—the energy deposit—first in the observation plane, by using a Lateral Energy Correction Function (LECF), then in the intrinsic shower plane, by applying an adequate mapping procedure. In both steps azimuthal.

Predictions of the hadronic interaction model EPOS~1.61 as implemented in the air shower simulation program CORSIKA are compared to observations with the KASCADE experiment. The investigations reveal that the predictions of EPOS are not compatible with KASCADE measurements. The discrepancies seen are most likely due to use of a set of inelastic hadronic cross sections that are too high., Comment: Journal of Physics G in press

Extensive air showers are generated through interactions of high-energy cosmic rays impinging the Earth's atmosphere. A new method is described to infer the attenuation of hadrons in air showers. The numbers of electrons and muons, registered with the scintillator array of the KASCADE experiment are used to estimate the energy of the shower inducing primary particle. A large hadron calorimeter is used to measure the hadronic energy reaching observation level. The ratio of energy reaching ground level to the energy of the primary particle is used to derive an attenuation length of hadrons in air showers. In the energy range from $10^6$ GeV to $3\cdot10^7$ GeV the attenuation length obtained increases from 170 \gcm2 to 210 \gcm2. The experimental results are compared to predictions of simulations based on contemporary high energy interaction models., Comment: accepted for publication in Physical Review D

AIMS: We wish to study the spectral dependence of the radio emission from cosmic-ray air showers around 100 PeV (1017 eV). METHODS: We observe short radio pulses in a broad frequency band with the dipole-interferometer LOPES (LOFAR Prototype Station), which is triggered by a particle detector array named Karlsruhe Shower Core and Array Detector (KASCADE). LOFAR is the Low Frequency Array. For this analysis, 23 strong air shower events are selected using parameters from KASCADE. RESULTS: The resulting electric field spectra fall off to higher frequencies. An average electric field spectrum is fitted with an exponential, or alternatively, with a power law. The spectral slope obtained is not consistent within uncertainties and it is slightly steeper than the slope obtained from Monte Carlo simulations based on air showers simulated with CORSIKA (Cosmic Ray Simulations for KASCADE). One of the strongest events was measured during thunderstorm activity in the vicinity of LOPES and shows the longest pulse length measured of 110 ns and a spectral slope of -3.6. CONCLUSIONS: We show with two different methods that frequency spectra from air shower radio emission can be reconstructed on event-by-event basis, with only two dozen dipole antennae simultaneously over a broad range of frequencies. According to the obtained spectral slopes, the maximum power is emitted below 40 MHz. Furthermore, the decrease in power to higher frequencies indicates a loss in coherence determined by the shower disc thickness. We conclude that a broader bandwidth, larger collecting area, and longer baselines, as will be provided by LOFAR, are necessary to further investigate the relation of the coherence, pulse length, and spectral slope of cosmic ray air showers., Comment: 13 pages, 21 figures. Nigl, A. et al. (LOPES Collaboration), Frequency spectra of cosmic ray air shower radio emission measured with LOPES, accepted by A&A on 17/06/2008

AIMS: We want to understand the emission mechanism of radio emission from air showers to determine the origin of high-energy cosmic rays. Therefore, we study the geometry of the air shower radio emission measured with LOPES and search for systematic effects between the direction determined on the radio signal and the direction provided by the particle detector array KASCADE. METHODS: We produce 4D radio images on time-scales of nanoseconds using digital beam-forming. Each pixel of the image is calculated for three spatial dimensions and as a function of time. The third spatial dimension is obtained by calculating the beam focus for a range of curvature radii fitted to the signal wave front. We search this multi-dimensional parameter space for the direction of maximum coherence of the air shower radio signal and compare it to the direction provided by KASCADE. RESULTS: The maximum radio emission of air showers is obtained for curvature radii being larger than 3 km. We find that the direction of the emission maximum can change when optimizing the curvature radius. Furthermore, we find a tentative increase of the curvature radius to lower elevations, where the air showers pass through a larger atmospheric depth. CONCLUSIONS: We conclude that the angular resolution of LOPES is sufficient to determine the direction which maximizes the observed electric field amplitude. However, the statistical uncertainty of the directions is not determined by the resolution of LOPES, but by the uncertainty of the curvature radius. We do not find any systematic deviation between the directions determined from the radio signal and from the detected particles. This result places a strong supportive argument for the use of the radio technique to study the origin of high-energy cosmic rays., Comment: 8 pages, 13 figures. Nigl, A. et al. (LOPES Collaboration), Direction identification in radio images of cosmic rays detected with LOPES and KASCADE, accepted by A&A on 12/06/2008

Am Beispiel eines sechsgeschossigen Burogebaudes mit Stutzenabstanden von ca. 8.60 m und Auskragungen der Flachdecke von 3.60 m wird die Anwendung der teilweisen Vorspannung ohne Verbund gezeigt.

LOPES is set up at the location of the KASCADE-Grande extensive air shower experiment in Karlsruhe, Germany and aims to measure and investigate radio pulses from Extensive Air Showers. Data taken during half a year of operation of 10 LOPES antennas (LOPES-10), triggered by showers observed with KASCADE-Grande have been analyzed. We report about results of correlations found of the measured radio signals by LOPES-10 with shower parameters., Comment: Proceedings of ARENA 06, June 2006, University of Northumbria, UK

When Ultra High Energy Cosmic Rays interact with particles in the Earth's atmosphere, they produce a shower of secondary particles propagating toward the ground. LOPES-30 is an absolutely calibrated array of 30 dipole antennas investigating the radio emission from these showers in detail and clarifying if the technique is useful for largescale applications. LOPES-30 is co-located and measures in coincidence with the air shower experiment KASCADE-Grande. Status of LOPES-30 and first measurements are presented., Comment: Proceedings of ARENA 06, June 2006, University of Northumbria, UK

Radio emission in extensive air showers arises from an interaction with the geomagnetic field and is subject of theoretical studies. This radio emission has advantages for the detection of high energy cosmic rays compared to secondary particle or fluorescence measurement methods. Radio antennas like the LOPES30 antenna system are suited to investigate this emission process by detecting the radio pulses. The characteristic observable parameters like electric field strength and pulse length require a calibration which was done with a reference radio source resulting in an amplification factor representing the system behavior in the environment of the KASCADE-Grande experiment. Knowing the amplification factor and the gain of the LOPES antennas LOPES30 is calibrated absolutely for systematic analyses of the radio emission., Comment: 5 pages, Proceedings of International Workshop on Acoustic and Radio EeV Neutrino detection Activities: ARENA, May 17-19, 2005, DESY Zeuthen

An analysis of muon and hadron rates observed in the central detector of the KASCADE experiment has been carried out. The data are compared to CORSIKA simulations employing the high-energy hadronic interaction models QGSJET, DPMJET, HDPM, SIBYLL, and VENUS. In addition, first results with the new hadronic interaction model neXus 2 are discussed. Differences of the model predictions, both among each other and when confronted with measurements, are observed. The hadron rates mainly depend on the inelastic cross-section and on the contribution of diffraction dissociation. The discrepancy between simulations and measurements at low primary energies around 5 TeV can be reduced by increasing the non-diffractive part of the inelastic cross-section of nucleon-air interactions. Examination of hadron multiplicities points towards harder spectra of secondary pions and kaons needed in the calculations., 14 pages, 7 figures, corresponding author: M. Risse, accepted for publication in J. Phys. G: Nucl. Part. Phys

A new transdiaphragmatic laparoscope technique is proposed which provides a large window for drainage that is rapid, safe and eliminates the need for one lung ventilation, drainage tubes, and painful incisions.

LOPES is an array of 30 radio antenna co-located with the KASCADE-Grande extensive air shower detector in Karlsruhe, Germany. It is designed as a digital radio interferometer for the detection of radio emission from extensive air showers. LOPES features high bandwidth and fast data processing. A unique asset is the concurrent operation with KASCADE-Grande. We report about the progress in understanding the radio signals measured by LOPES. In addition, the status and further perspectives of LOPES and the large scale application of this novel detection technique are sketched.

The recent successes being achieved with combination chemotherapy regimens, such as FAMTX (fluorouracil [5-FU], doxorubicin, methotrexate), EAP (etoposide, doxorubicin, cisplatin), and ELF (etoposide, leucovorin, 5-FU), strongly indicate that gastric cancer is chemosensitive. With these regimens, objective remission rates of more than 50% were recorded, including approximately 10% complete remissions (CRs). Moreover, some of these CRs were histopathologically confirmed. The finding that locally advanced disease (LAD) and technically unresectable disease could be rendered resectable by preoperative chemotherapy (EAP) was important. Thirty-six patients with LAD had been treated in a phase II trial with preoperative EAP, inducing 24 (70%) overall remissions (two clinical CRs, six pathologic CRs, 16 partial remissions [PRs] in 35 evaluable patients. Twenty-one patients were disease-free after chemotherapy with or without second-look surgery. The median survival time was 18 months for all patients and 24 months for disease-free patients. At 30+ months, 21% of all patients are still living disease-free. The expected survival of patients with unresectable LAD is approximately 4 to 6 months without any treatment and 6 to 9 months with standard chemotherapy. Compared with the latter results, the preoperative use of effective regimens (eg, EAP) seems to improve prognosis of patients with LAD. Moreover, such a multimodal approach may increase the number of long-term survivors among patients with resectable gastric cancer, especially those whose stage indicates a high risk of relapse (stages IIIa or IIIb). However, partly because of the severe toxicities (myelosuppression, nausea/vomiting), a considerable number of patients cannot be treated with these new regimens for the following reasons: Two of three patients with gastrointestinal disease are older than 60 years. Nontumorous diseases of the cardiovascular system, kidney, and others are frequent in this age group and may complicate or even prevent treatment with aggressive regimens. Considering the predominantly palliative treatment intentions in far advanced (metastasized) gastric cancer, regimens with low toxicities and acceptable activity should be preferred. For these reasons, we developed and investigated the combination ELF in a phase II trial in elderly patients (greater than 65 years) and in patients with cardiac risks who could not be treated with anthracyclines. The overall response rate in 51 evaluable patients was 53% (27 of 51) including six clinical CRs (12%). The median remission duration was 9.5 months and the median survival time was 11 months. Tolerability was excellent. Only 16% and 4% of patients, respectively, experienced WHO grades 3 and 4 leukopenia. Nausea/vomiting and mucositis/stomatitis were mild.(ABSTRACT TRUNCATED AT 400 WORDS)

Die tuberose Sklerose ist eine seltene Erkrankung, bei welcher Hamartome im Gehirn, in der Netzhaut, in der Haut sowie in mehreren inneren Organen vorkommen konnen. Die klassische Form der Erkrankung mit geistiger Retardierung, epileptiformen Anfallen und Adenoma sebaceum ist leicht zu erkennen. Die inkompletten Formen konnen erhebliche diagnostische Schwierigkeiten bereiten. Angiographisch zeigt das Krankheitsbild Veranderungen, die nicht sicher vom Bild maligner Tumoren abzugrenzen sind. Maligne Tumorbildung ist beim Morbus Bourneville extrem selten. Bei rechtzeitiger Diagnose kann die Nephrektomie vermieden werden. – Berichtet wird uber zwei weibliche Patienten, wobei einmal die Diagnose eines Morbus Bourneville primar durch die Angiographie der Nieren gestellt wurde. Beide Nieren konnten trotz groser Tumoren organerhaltend operiert werden. Im zweiten Fall wurde bei beidseitigen Nierenhamartomen von einer Operation abgesehen. – In beiden Fallen bestanden typische Veranderungen an den Fingern und Zehen sowie intrazerebrale Verkalkungen. Einmal war die Lunge beteiligt. Tuberous sclerosis is a rare disease in which hamartomas may be found in the brain, the retina, the skin and in other internal organs. The classic form of the disease showing mental retardation, epilepsy and adenoma sebaceum is easily recognised. Incomplete forms, however, can provide considerable diagnostic difficulties. Angiographically, appearances are found which cannot be differentiated with certainty from those of malignant tumours. Malignant tumours are very rare in this condition. Nephrectomy can be avoided if the diagnosis is made at an early stage. Two female patients are reported, in one of whom the diagnosis was made by renal angiography. Despite the presence of large tumours in both kidneys, these organs could be preserved by surgery. In the second patient there were also bilateral renal hamartomas, but surgery was not carried out. Both cases showed typical changes in the fingers and toes as well as intracerebral calcification, and in one the lungs were affected.

The occurrence of multiple sclerosis (MS) in several members of families has been observed in 4.8% of 105 MS patients from a limited epidemiological area of Rostock. Typing of the HLA antigens in 4 affected sib-pairs showed two identical HLA haplotypes in 3 of the pairs: 1 pair shared one haplotype. These findings point to a dominant mode of inheritance of the disease susceptibility gene together with the HLA haplotype. The assessment of family studies in MS is discussed.

Tuberous sclerosis is a rare disease in which hamartomas may be found in the brain, the retina, the skin and in other internal organs. The classic form of the disease showing mental retardation, epilepsy and adenoma sebaceum is easily recognised. Incomplete forms, however, can provide considerable diagnostic difficulties. Angiographically, appearances are found which cannot be differentiated with certainty from those of malignant tumours. Malignant tumours are very rare in this condition. Nephrectomy can be avoided if the diagnosis is made at an early stage. Two female patients are reported, in one of whom the diagnosis was made by renal angiography. Despite the presence of large tumours in both kidneys, these organs could be preserved by surgery. In the second patient there were also bilateral renal hamartomas, but surgery was not carried out. Both cases showed typical changes in the fingers and toes as well as intracerebral calcification, and in one the lungs were affected.

Previous EAS investigations have shown that for a fixed primary energy the charged particle density becomes independent of the primary mass at certain (fixed) distances from the shower core. This feature can be used as an estimator for the primary energy. We present results on the reconstruction of the primary energy spectrum of cosmic rays from the experimentally recorded S(500) observable (the density of charged particles at 500 m distance to the shower core) using the KASCADE‐Grande detector array. The KASCADE‐Grande experiment is hosted by the Karlsruhe Institute for Technology—Campus North, Karlsruhe, Germany, and operated by an international collaboration. The constant intensity cut (CIC) method is applied to evaluate the attenuation of the S(500) observable with the zenith angle and is corrected for. A calibration of S(500) values with the primary energy has been worked out by simulations and was applied to the data to obtain the primary energy spectrum (in the energy range log10[E0/GeV]∈[7.5,9]). ...

Based on the KASCADE multi-detector system with its large hadron calorimeter and using the CORSIKA simulation program with the implemented high-energy hadronic interaction models QGSJET, VENUS, DPMJET, SIBYLL, and HDPM, a method for the test of models by comparing el ent rates is described. Preliminary results show differences of the model predictions both among each other and when confronted with measurements. The rates are strongly influenced by the inelastic cross sections and the elasticity, especially by the contribution of diffractive dissociation. The discrepancy to measurements at primary energies below similar or equal to 3 (.) 10(13) eV can be reduced by increasing the non-diffractive inelastic cross section.

Measurements of electron, muon, and hadron lateral distributions of extensive air showers as recorded by the KASCADE experiment are presented. The data cover the energy range from about 5x10^14 eV up to almost 10^17 eV and extend from the inner core region to distances of 200 m. The electron and muon distributions are corrected for mutual contaminations by taking into account the detector properties in the experiment. All distributions are well described by NKG-functions. The scale radii describing the electron and hadron data best are approx. 30 m and 10 m, respectively. We discuss the correlation between scale radii and `age' parameter as well as their dependence on shower size, zenith angle, and particle energy threshold., Comment: 28 pages, 14 figures, Accepted for publication in Astroparticle Physics

The temporal structure of the extensive air shower (EAS) muon component (E-thres = 2.4 GeV) is studied at sea level by measurements of the muon arrival time distributions using the muon detection facilities of the KASCADE central detector. Data have been analysed for EAS core distances up to 110 m for primary energies around the knee region. The time structure of the EAS muon component is represented by the distributions of the mean, median, first quartile and the third quartile of the muon arrival time distributions relative to the foremost muon. The EAS time profiles (variation with the distance from the EAS center) are studied along their dependencies on the angle of incidence and the energy-indicative muon number N-mu(tr). Effects of the fluctuation of the arrival time of the first registered muon are scrutinised and corrected. The experimental results are compared with EAS Monte Carlo (CORSIKA-GEANT) simulations, fully including the detector responses and illustrating the phenomenological features. The comparisons, though generally in fair global agreement, revealed that the simulations underestimate the shower thickness and show nearly no dependence on the mass composition if the time resolution of the apparatus is realistically taken into account. (C) 2001 Elsevier Science B.V. All rights reserved.

The main goals of the KASCADE (KArlsruhe Shower Core and Array DEtector) experiment are the determination of the energy spectrum and elemental composition of the charged cosmic rays in the energy range around the knee at ca. 5 PeV. Due to the large number of measured observables per single shower a variety of different approaches are applied to the data, preferably on an event-by-event basis. First results are presented and the influence of the high-energy interaction models underlying the analyses is discussed., 3 pages, 3 figures included, to appear in the TAUP 99 Proceedings, Nucl. Phys. B (Proc. Suppl.), ed. by M. Froissart, J. Dumarchez and D. Vignaud