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Notizen: At the new Munich high flux reactor FRM-II, the Munich Accelerator for Fission Fragments (MAFF) is under development. The main objective will be the production and study of new very heavy elements (Z〉100). To obtain this goal, intense beams of neutron rich isotopes (70〈A〈160) are required. Thermal neutron induced fission is considered the most suitable method to produce these isotopes due to the large fission cross section and high thermal neutron flux (〉1014 n/s*cm2) available at the new reactor. The target ion source design is based on the ANUBIS source at OSIRIS in Studvik, optimized for very high neutron fluxes. Using 1 g of 235U diluted in a graphite target, intensities of several 1011 ions/s for 91Kr, 132Sn, or 144Cs, e.g., are expected after mass separation. These singly charged ions will be charge bred in an electron cyclotron resonance ion source and then injected into the MAFF-LINAC to reach the energies at the Coulomb barrier. The production of intense ion beams of neutron rich isotopes by thermal neutron induced fission, the development of the target ion source, and the development of the fission target will be presented. © 2002 American Institute of Physics.

Notizen: In this letter we present calculations by three-dimensional finite element method and measurements by convergent beam electron diffraction of the displacement field resulting from misfitting Ge0.85Si0.25 islands on Si(001). A good agreement between the results of both methods indicates that the three-dimensional finite element method is a reliable tool to calculate the strain, and thus the stress field, in such nanostructures. As a result both methods show that the substrate substantially takes part in the elastic relaxation process in such heteroepitaxial systems.

Notizen: Background  Thaumetopoea processionea L. (order Lepidoptera), the oak processionary moth, is found in oak forests in most European countries. Its third to sixth larval instars are armed with poisonous hairs (setae) containing an urticating toxin (thaumetopoein) potentially harmful to humans. Because T. processionea infests trees at the edges of forests or standing alone people frequently come into contact with its setae. In the woodland bordering on the western suburbs of Vienna conditions favouring its increase have led to frequent outbreaks of lepidopterism.Objectives  To determine the incidence of lepidopterism in a suburban environment with three separate caterpillar-infested oak trees and to ascertain the frequency of the various symptoms of lepidopterism and the manner of contact with setae.Methods  We conducted a telephone survey of all the households/institutions located within 500 m of the infested trees. To gain more information on patients' symptoms and on situations likely to lead to increased contact with setae we asked those who reported cutaneous reactions to complete a questionnaire. As part of the environmental study we described the outbreak site, examined patients and, with tape-strip samples taken from the surface of the soil, looked for setae persisting in the environment.Results  Of 1025 people surveyed 57 (5·6%) reported one or more symptoms of lepidopterism: 55 (96%) reported pruritus, 54 (95%) dermatitis, eight (14%) conjunctivitis, eight (14%) pharyngitis and two (4%) respiratory distress. The questionnaire was returned by 37 (69%) of the individuals with dermatitis. Of those, 16% had reacted with weal formation, 49% with papular rash and 22% with toxic irritant dermatitis. In 13% of respondents it was not possible to define the reaction. The risk factor analysis showed that airborne contamination was the most important cause: 97% of people had frequently passed an infested tree, 57% lived near a tree (in a neighbouring garden) and 32% had a tree in their own garden. Direct contact with larvae was of minor importance (38%). In four of the tape-strip samples intact setae were identified 1 year after the infestation.Conclusions  Lepidopterism caused by T. processionea is a public health problem of increasing significance. In years with outbreaks of the pest it can reach epidemic proportions in communities located near infested trees. Contact with airborne setae was mainly responsible for the occurrence of the disease.

Notizen: Summary Background The thickness of the sunscreen layer that is actually applied by consumers under usual conditions has been determined for photoprotective lotions and creams; however, this question is still unanswered for photoprotective lipsticks. Objectives To assess lipstick thickness (area density) and frequency of application per day for two commercially available photoprotective lipsticks with different consistency. Methods The study consisted of a laboratory test and a field experiment. In the laboratory test the applied lipstick thickness was determined as area density in mg cm−2 for a group of 28 panellists under standardized conditions. In a separate group of 18 subjects we assessed the area density and the frequency of application per day for two photoprotective lipsticks during a 6-day skiing course. Results In the laboratory test the median and 95% confidence interval of the area density was 0·98 mg cm−2 (0·66–1·65) and 0·86 mg cm−2 (0·63–1·40) for products A and B, respectively. The respective values of the field experiment were 1·58 mg cm−2 (0·79–2·23) (product A) and 1·76 mg cm−2 (1·16–3·50) (product B). Only 11% of all applications of lipstick A and 6% of all applications of lipstick B reached the reference area density of 2·0 mg cm−2. The difference between the median of the area density for lipstick A (firm consistency) and lipstick B (soft consistency) was not statistically significant. No statistically significant influence on the area density was found for age, sex, photobiological skin type or regular lipstick use. The median daily frequency of application was 2·2 times for lipstick A and 3·0 times for lipstick B. Conclusions Our investigation shows that photoprotective lipsticks are applied in a much thinner layer than recommended by international standards (2 mg cm−2). This results in a significant reduction of the photoprotective capacity. Furthermore, the frequency of application is too low for adequate protection. Therefore, we propose that the sun protection factor (SPF) should be assessed for an area density that reflects the actual usage patterns. As long as the test protocol is not adapted to the reduced area density, photoprotective lipsticks with high and ultrahigh SPF should be recommended, especially for individuals with increased risk for the development of lip malignancies.

Notizen: Spectral diffusion (SD) in polymethylmethacrylate (PMMA) doped with free-base tetraphenylporphine is investigated at 0.5–4.2 K on a time scale of 3–106 s via optical hole burning. Two contradictory results—within the framework of the two level system (TLS) model—are obtained. The first one is the absence of aging effects at temperatures near 4 K which puts the upper limit for the TLS relaxation times at tens of minutes. The second one is an intensive superlogarithmic SD on the whole time scale of the experiment, which is evidence for the presence of very slow relaxations, independent of the sample history on a time scale of up to two months. The results presented provide clear evidence of a deviation of SD behavior from the TLS model predictions at moderately low temperatures. The concept of structural relaxations is applied for a qualitative interpretation of the experimental data. © 2000 American Institute of Physics.

Notizen: The distribution of secretoneurin-like immunoreactivity, a peptide derived from secretogranin II, was studied by means of immunocytochemistry and compared to the pattern of staining for substance P- and enkephalin-like immunoreactivities in the human basal forebrain, with special reference to the basal ganglia. Secretoneurin-like immunoreactivity was characterized by gel filtration and reversed-phase high pressure liquid chromatography analysis. Chromatographic analysis revealed a single peak for secretoneurin-like immunoreactivity. No secretoneurin-immunopositive forms of high molecular weight were found. Secretoneurin-like immunoreactivity appeared mainly in dot- and fibre-like structures. In addition, a band-like terminal staining (woolly fibres) that has been shown by others for substance P- and enkephalin-like immunoreactivities, was also observed for secretoneurin-like immunoreactivity. Medium-sized cells were found arranged in clusters or singly within the caudate and putamen. In the basal ganglia, a high density of secretoneurin-like immunoreactivity was found in the internal segment of the globus pallidus, the ventral pallidum and in the pars reticulata of the substantia nigra. In these areas the immunostaining appeared mainly as woolly fibres. The bed nucleus of the stria terminalis and medial amygdala displayed a high density of fine beaded secretoneurin-like immunoreactive fibres, sometimes forming pericellular contacts. The nucleus basalis of Meynert was highly innervated by secretoneurin-like immunoreactive fibres, mainly in the form of woolly fibres. In general, a large overlap was found between secretoneurin- and substance P-like immunoreactivity in all examined areas of the basal ganglia. In the bed nucleus of the stria terminalis and medial amygdala secretoneurin-like immunoreactivity was distributed very similarly to enkephalin-like immunoreactivity. These data provide evidence that in different subsets of neurons and neuronal pathways secretoneurin-like immunoreactivity coexists with substance P- and enkephalin-like immunoreactivity in several areas of the human brain.