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Notes: Abstract  The adulteration of wine with glycerol is considered to be a problem in European wine-producing countries. The latest control methods are mainly based on the detection of impurities from commercial products, but suffer from the raising efficiency of the purification processes. As there is little chance of being able to identify glycerol from different sources on the basis of a method which uses only one isotope, a multielement approach was tested. Glycerol from wine showed the lowest relative enrichment with D, mainly in position C-2, a relatively high 18O content, and very negative δ13C values, which significantly correlated with those of ethanol from the same wines. The isotopic data of glycerol samples from different sources were in agreement with those given by indices of origin (impurities). These data allowed us to identify the origin of these glycerol samples, i.e. whether they were produced industrially or synthesised by animals or plants. Glycerol of plant origin was most similar to glycerol found in wine. The combination of several isotopic data by discriminance analysis yielded clusters of data obtained from glycerol samples of similar origin. Taking into account the characteristics of possible mixtures, proof that wine has been adulterated depends on the origin and isotope levels of the added compound. This study showed that it is possible to prove that wine has been adulterated with glycerol from other sources when the latter is present at a concentration of 15% of the total glycerol content.

Notes: Abstract An analysis of the population genetics of the meiofaunal polychaete Petitia amphophthalma Siewing, 1956, in which the RAPD-PCR method was applied to 103 individuals from eight populations, some of them very far apart (Atlantic: Florida, Tenerife, France; Mediterranean: two Greek islands, Tunisia; Red Sea: Egypt), gave closely reproducible results. In the band patterns produced with 13 decamer primers, a total of 195 genetic characters was detected. The data were evaluated by a number of methods, including the cluster programs UPGMA, WPGMA and neighbour-joining. The detected genetic distances between the populations vary between 58.9 and 66.6, but 97% of the genetic characters, although polymorphic, are found in at least two populations and usually in all the others as well. Phenograms of the analyses find four population clusters [Florida, France (Atlantic), the Mediterranean and Tenerife]. They are, however, not completely congruent and show low bootstrap values at the junction points of the clusters (with the exception of the Tenerife cluster). Mediterranean P. amphophthalma form a cohesive population, although within it the genetic distances are graded in parallel with the geographic distances between the sites. The colonization of Tenerife, an island of relatively recent volcanic origin, can be taken as evidence that this meiofaunal species can become dispersed not only along coastlines but also across expanses of open water. However, the severely restricted variability of these populations implies that in this case a founder effect has operated, and that transport over open water is not a routine event but extremely rare. The absence of the species on the Australian coast and, for instance, on the Galapagos Islands indicates that there has been no continuous gene flow across the oceans. The idea that all the populations investigated belong to one cosmopolitan species is discussed.

Notes: Abstract The purpose of the following clinical study was to determine the prevalence, size, sex and side predilection of supernumerary nipples. Out of 502 patients, 28 (5.6%) exhibited a supernumerary nipple of small (only areola with diameter less than 30% of normal areola) or middle size (areola with nipple, diameter 30%–50% of normal areola). The male/female ratio was 20/8 and left/right side ratio 15/7 in males and 5/4 in females. Conclusion A supernumerary areola or a supernumerary areola with nipple is a frequent finding. There is a higher prevalence for the left side and male gender.

Notes: Abstract Due to the observation of severe neurological symptoms in single patients as well as brain imaging, neuropsychological and neurophysiological abnormalities, the long-term prognosis of treated phenylketonuria is still under discussion. We investigated the neurological outcome of 57 (24 male, 33 female) patients with phenylketonuria (diet onset 〈3 months) at a mean age of 23.6 (17–33) years in comparison to control subjects. Methods used were a clinical-neurological examination, tests for fine motor abilities, IQ test (WAIS-R), a neuropsychological attention task and MRI (30 patients only). Tremor was increased in the patients (28%) compared to controls (15%). Fine motor abilities were significantly reduced in three areas: hand-wrist steadiness, finger-hand dexterity and hand-wrist speed. Tremor as well as reduced fine motor skills were not associated with treatment-related variables, e.g. diet onset, strictness of biochemical control or amount of MRI white matter change. IQ was lower in patients (mean 97.6) compared to matched control subjects (mean 105.5). IQ at 12 years was correlated with biochemical control from birth up to the age of 12 and remained stable up to adult age, independent of biochemical control after 12 years of age. In contrast to the other outcome parameters, the performance in a neuropsychological attention task was influenced by the concurrent plasma phenylalanine concentration. Specific late-onset neurological impairment was not identified in this sample of early-treated adults with phenylketonuria. Conclusion Careful neurological investigation revealed subtle symptoms of brain damage even after early-initiated treatment in adult patients with phenylketonuria. At present it cannot be excluded that further neurological deterioration could emerge later in life. Thus, patients with phenylketonuria – either on or off diet – should be monitored throughout life.

Notes: Epitaxial ferromagnetic La0.8Sr0.2MnO3−δ films have been sputtered on SrTiO3 bicrystal substrates. Etched patterns crossing the bicrystal grain boundary are compared with identical patterns not crossing it. The films were annealed at different conditions and their magnetoresistance measured as a function of temperature T and of in plane magnetic field H strength and direction. Annealing at 900 °C was found to modify the grain boundary and to increase its magnetoresistance. For H=±80 Oe parallel to the grain boundary and T=32 K narrow magnetoresistance peaks of 60% height are measured. They are interpreted in the frame of an in plane magnetotunneling structure. © 1998 American Institute of Physics.

Notes: Summary. Radiological and orthopaedic outcome in severe and moderate haemophilia A and B patients undergoing long-term prophylactic treatment were prospectively investigated focusing on the age of onset of prophylaxis and the number of joint bleedings prior to treatment. We report on 21 patients with severe and moderate haemophilia A and B receiving prophylactic treatment of between 3.1 and 16.1 year's duration. Three patient groups were evaluated according to the age at onset of prophylaxis. In group I prophylactic treatment was initiated in the first 2 years of life. Patients in group II received prophylaxis at the age of 3–6 years. Late-onset or secondary prophylactic treatment was started at the age of 6 years and above in seven patients (group III). All patients received virus-inactivated F VIII or F IX concentrates at dosages of 30–50 IU/kg body weight i.v. three times per week for those with haemophilia A and twice per week for those with haemophilia B. Elbow, knee and ankle joints were investigated at 3–4-yearly intervals according to the radiological and orthopaedic scores recommended by the World Federation of Haemophilia. The total number of joint bleedings before and after start of prophylaxis were recorded in all patients. In group I 7/8 patients had unaffected joints with constant radiological and orthopaedic scores of zero or 1, after a median of 11.25 years of prophylactic treatment. One patient in this group demonstrated mild radiological alterations (score 4). Patients in group II showed neither radiological nor orthopaedic alterations at study entry. Surprisingly, worsening joint scores could be detected despite ongoing prophylaxis after the 3-year interval (median orthopaedic score 4, median radiological score 8). Treatment group III already showed considerable joint damage at study entry with a median radiological score of 11 (0–33) and a median orthopaedic score of 4 (0–11). Despite prophylactic treatment, both radiological (median 19.5, range 2–47) and orthopaedic scores (median 8, range 2–12) deteriorated after 3 years. Prior to onset of prophylaxis, no or only one joint bleeding occurred in treatment group I. In group II, a median of six joint bleeds (range 1–8) was reported before prophylaxis was started. Patients in group III usually experienced a median of more than 10 joint haemorrhages (range 6–10 or more). Under prophylactic treatment the number of joint bleedings decreased significantly in group II and III. However, radiological and orthopaedic scores increased as a sign of progressing osteoarthropathic alterations in patients reporting more than five joint haemorrhages before onset of prophylaxis whereas no joint alterations could be assessed in patients with no or only one joint bleeding episode prior to prophylaxis. Even a small number of joint bleedings seems to cause irreversible osteoarthropathic alterations leading to haemophilic arthropathy. Once apparent, further progression of joint damage could not be arrested despite of prophylactic treatment (groups II and III). In order to prevent haemophilic arthropathy, effective prophylaxis should be started before or at least after the first joint bleeding in severe haemophilia A and B.

Notes: A versatile model for ultraviolet (UV) laser ablation of polymers is presented, which is very successfully applied to the calculation of a variety of different properties of this process, including the influence of plume attenuation dynamics. The polymer is described as a system of chromophores with two possible electronic states. The model is based on the combination of photothermal decomposition and photodissociative bond breaking in the electronically excited state. Laser induced chemical modifications are incorporated via different absorption coefficients for the initial and for the modified polymer after absorption of UV light. Dynamic attenuation of the expanding ablation plume and heat conduction are taken into account. The results of the theoretical calculations are compared with the results of three different series of experiments performed with polyimide (PI) and polymethylmethacrylate at the excimer laser wavelength 248 nm and with PI also at 308 nm: (1) Measurement of the ablation rate as a function of fluence for four different pulse durations between 20 and 250 ns; (2) Measurements of the ablation rate as a function of fluence for five different laser irradiation spot radii between 10 and 150 μm, and (3) Time resolved measurement of the dynamic plume attenuation at the ablating laser wavelength as a function of fluence for four different pulse durations between 20 and 250 ns. The model leads to a prediction of etch rates, ablation thresholds, plume attenuation, and surface temperatures during the ablation process, which is in good agreement with the experimental results. The observed increase of the ablation rate with increasing pulse length and with decreasing laser spot size can be explained by the model as a consequence of laser induced modified absorption in combination with the dynamic shielding of the expanding plume. © 1998 American Institute of Physics.

Notes: alpha-Alumina and boehmite particles were synthesized by coprecipitation followed by a hydrothermal treatment. X-ray diffraction (XRD) indicated that alpha-Al2O3 was the major phase and coexisted with 4% of boehmite in the presence of the alpha-Al2O3 seeds. On the other hand, a single boehmite phase was obtained in the absence of the alpha-Al2O3 seed particles. The powder densified in the temperature range from 1050° to 1350°C. High-resolution transmission electron microscopy (HRTEM) showed that the particle size of the synthesized alpha-Al2O3 was 60 nm. The surface area was 245 m2/g.

Notes: The primary-extinction problem for X-ray diffraction by perfect crystals is treated using the Becker–Coppens iterative procedure within the Takagi–Taupin equations. An analytical approximation for the primary-extinction factor yp describing both the effects of the X-ray multiple scattering and the absorption processes within the perfect crystal of an arbitrary shape is derived. The solution differs from the known expressions given by Zachariasen and Becker & Coppens on the basis of the Hamilton–Darwin intensity transfer equations and in the limiting case of a non-absorbing crystal it concurs with the Kato–Becker formula found in the Laue approximation of the dynamical theory. The theoretical results are consistent with experimental data of a number of reflections of Ge and Si single-crystal spheres measured at X-ray wavelengths λ = 0.56, 0.71 and 1.54 Å with a laboratory CAD-4 and a Huber four-circle diffractometer at HASYLAB, DESY, Hamburg, Germany. Two novel features are discussed. First, it is shown that by neglecting the X-ray absorption effect the calculated extinction factor yp is close to the value given by the Becker–Coppens formula. Second, it was found that for absorbing spherical crystals with μR ≥ 1 absorption effects cannot be treated separately from the primary-extinction phenomenon because of imaginary dispersion corrections to the atomic form factors. The experimental data are fitted to the Becker–Coppens and present theoretical models. The best fits are found to relate to the present model and produce relatively low R factors of 3 to 6% for the Bragg intensities measured in the cases of Si and Ge spherical crystals.