ALBERT

Notes: Summary A method, using seismic data, is presented for the mapping of the irregular boundary of an elastic half-space. It furnishes the shape of the corrugations in terms of the measured displacement field generated by plane dilatational or shear waves reflected from the boundary.

Notes: Summary Heterologous antiserum to the 3 biotin-dependent carboxylases was prepared by selective removal of these enzymes from human liver on an avidin-sepharose column. A carboxylase-avidin-sepharose matrix was used as an antigen to produce anti-carboxylase antibodies. The resultant antisera can be used to purifiy the specific carboxylases, to prepare monoclonal antibodies to these enzymes or to study inherited carboxylase deficiencies and biotin-dependent intermediary metabolism.

Notes: Abstract The northern Pacific asteroid Asterias amurensis (Lütken) has been recently introduced to Tasmania and is now well-established in east and southeast Tasmania. This sea star is conspicuous throughout the Derwent River estuary and is particularly abundant in the Hobart port area. Reproduction of two populations of A. amurensis at Sullivans Cove and at Sandy Bay was investigated from August 1993 to October 1994 by gonadal histology and measurement of the gonad index (GI). An intense period of vitellogenic and spermatogenic growth started in April, with the breeding condition reached by June. In 1994, peak GI was recorded at Sullivans Cove in July and at Sandy Bay in August. Although these data indicated that the Sullivans Cove population spawned before the Sandy Bay population, histological examination revealed that major spawning activity occurred in both populations from July onwards. In the early part of the breeding season, gametogenesis proceeded in parallel with spawning, with released gametes being replaced by continual gametogenesis. Maintenance of a higher GI during the early part of the breeding season at Sandy Bay was due to prolonged gametogenic replacement at this site. Spawning continued to October 1994, resulting in a sharp decline in the GI. The cyclic expansion and regression of the genital haemal sinus coincident with germinal proliferation and growth, respectively, support the contention that haemal fluid provides nutrients for gametogenesis. In Tasmania, A. amurensis experiences temperature and photoperiod regimes similar to those experienced by endemic populations of this species in the north Pacific. Comparison of reproduction of A. amurensis in Japan and Tasmania at similar latitudes shows that gametogenesis of the northern and southern populations is 6 mo out of phase. This phase shift provides evidence for photoperiodic regulation of gametogenesis in A. amurensis. The similar trend in sea-temperature regimes associated with the stages of gametogenesis in northern and southern populations suggests that temperature also plays a modulatory role. Based on the periodicity of reproduction and the ontogeny of A. amurensis, the planktotrophic larvae of this species would be expected to be in the plankton for several months from the end of winter through summer. Considering the highly fecund, dispersive life-history of A. amurensis, the southeast Tasmanian populations have considerable potential to serve as a seed source for establishment of new populations of this asteroid elsewhere in Tasmania and in mainland Australia.

Notes: Abstract Biotinidase deficiency is an autosomal recessively inherited disorder in the recycling of the vitamin biotin. The most common mutation that causes profound biotinidase deficiency in symptomatic individuals is a deletion/insertion (G98:d7i3) that occurs in exon B of the biotinidase gene. We now report the second most common mutation, a C-to-T substitution (position 1612) in a CpG dinucleotide in exon D of the biotinidase gene. This mutation results in the substitution of a cysteine for arginine538 (designated R538C) and was found in 10 of 30 symptomatic children with profound biotinidase deficiency, 5 of whom also have the G98:d7i3 mutation. This mutation was not found in DNA samples from 32 individuals with normal biotinidase activity, but was found in one individual with enzyme activity in the heterozygous range. This mutation was not detected in 371 randomly selected, normal individuals using allele-specific oligonucleotide hybridization analysis. Aberrant biotinidase protein was not detectable in extracts of fibroblasts from a child who is homozygous for the R538C mutation, but was present in less than normal concentration in identical extracts treated with β-mercaptoethanol. Because there is no detectable biotinidase protein in sera of children who are homozygous for the R538C mutation and in combination with the deletion/insertion mutation, the R538C mutation likely results in inappropriate intra- or intermolecular disulfide bond formation, more rapid degradation of the aberrant enzyme, and failure to secrete the residual aberrant enzyme from the cells into blood.

Notes: Summary 1. In populations of the dipteran Phryne cincta (2n = 6+XX♀, XY♂) several X-chromosomes of different structure are present. These are allocyclic in contrast to the (eucyclic) autosomes, as seen in their behaviour in mitosis and meiosis and in their varied appearance in polytene nuclei (comp. Wolf 1950, 1957). 2. The polytene autosomes (2–4 s. Pig. 7) differ from each other in easily recognizable characters and form no chromocenter. The polytene X-chromosome is always relatively much shorter than the autosomes and more or less β-heterochromatic (granular or indistinctly banded) in larvae, raised at room temperature. In larvae raised at low temperature (0–4° C) it passes through a morphogenesis, growing to normal or nearly normal length and assuming the aspect of an euchromatic element (comp. X a in Figs. 3 and 4). 3. Two stocks, characterized by different X-chromosomes, symbolized by X a and X b or a and b respectively, were chosen for the experiments. In mitosis both these X-chromosomes are rod-like, a is as long as autosome 4, b has only half its length (Figs. 1, 2a–d). 4. Just before pupation, in polytene nuclei of larvae raised at low temperature a and b are of almost equal length. They differ from each other in several inversions and in the appearance of two large α-heterochromatic bands in a (α2 and α3, Fig. 5; “α-quantum-difference”). 5. The α-bands, especially the large block α2, show a considerable intercellular variation in their relative DNA-content (measured as length of the α-element). The mean DNA-content is negatively correlated with the degree of stretching of the chromosome (Table 1). 6. In polytene nuclei of female hybrids from the crosses aaxbY or bbxaY, a and b are unpaired or incompletely paired in variable degrees (Figs. 7, 8a–e). The heterozygotic chromosome pair can be devided into 5 segments (I–V, Fig. 6), three of which are marked by clearly defined structural differences (I, III, V). 7. The pairing-segments II and IV, exhibiting an identical and parallel sequence of discs in a and b, allow six crossing-over recombinations (cb, db, eb, fb, gb, hb; comp. Figs. 9, 10). These new types of X-chromosomes occur in very different frequencies in the progeny of the hybrid ♀♀ when backcrossed to standard ♂♂ bY. The types eb and fb occur relatively rarely, while gb and hb are extremely rare (Figs. 9, 10, Table 2); in 70% of the progenies they are not present. The recombination-process is mainly restricted to pairing segment IV. 8. In a and in the crossover-chromosomes c, e, g very often a threadlike constriction appears in the region of α 2, resulting mostly in a pseudofragmentation with more or less independent location of the two chromosome parts (Figs. 3d, 8f-i, 11a). A variety of kinds of fusion between the parts and the autosomes, especially in their α-heterochromatin, is possible (Figs. 3e, 8g–i). 9. Lowering the breeding-temperature increases the duration of development, the size of the larvae, and the lengthening and euchromatization of the β-heterochromatic parts of the X-chromosomes. In the hybrids it also results in increasing the recombination rate (Table 3 and 4). 10. In the main experiments, hybrid offspring from the same parental pair, were raised at different temperatures: some individuals at high (20–26° C), others at low temperatures (2–8° C). The resulting two series of imagos were kept in optimal or room temperatures (14–22° C). The female progeny of 23 hybrids raised at elevated temperature and of 27 hybrids raised at low temperature, i.e. 1766 and 2102 X-chromosomes respectively, have been tested (Table 5, Fig. 12). No or only little recombination occurred in hybrids raised at 20–26° C (mean = 2.4%) in contrast to their sisters raised at 2–8° C, which gave a relative high frequency (mean = 18,2%). 11. In these cases only the first egg batches of each hybrid ♀ have been evaluated. Later progeny exhibits a reduction in crossing-over frequency in cold-raised hybrids with growing age. The mean rate of recombination of 14 hybrids is lowered from 16,6% in the first to 7,1% in the following progeny (n=1813; Table 6, Fig. 15) presumably as a consequence of keeping the imago in higher temperature. 12. The results from several larger groups of cold-raised sister hybrids more or less clearly demonstrate a bimodal distribution of recombination values (Fig. 13) suggesting a difference in recombination potentiality between the two X-chromosomes in the mother of the hybrids. Some data indicate the recombination rate in the X-chromosome as negatively correlated with the rate of development (Table 7). 13. The Mendelian ratio, 1∶1, of the non-recombinant types, ab and bb, is found in the progeny of the warm-raised hybrids (1769∶1778). This ratio is shifted considerably in favour of type ab in the case of low temperature hybrids (1996∶1626). In the recombinant types, cb and db, the ratio is always markedly shifted in favour of cb, irrespective of temperature (712:343). There must exist a causal relation between the Mendelian anomaly and the recombination process the nature of which is yet unknown. 14. The temperature at which a larva is raised effects both the frequency of crossing over and the stretching and euchromatization of β-heterochromatin in the polytene X-chromosome. This parallele suggests that structural changes comparable to those in the polytene chromosomes are induced by low temperature in meiotic chromosomes as well, and that these changes are responsible for the effect on the crossing-over frequency. These changes, which are reversible by age or temperature, are supposed to cause the extention of the “effective pairing” (as in euchromatic segments) on β-heterochromatic elements, which normally are unpaired. 15. The so-called “α-quantum-difference”, i.e. the difference in the amount of α-heterochromatin (or in the “relative DNA-content”) between the X-chromosomes is considered to be causally related to the crossing-over process (“α-differential-effect”). By way of a potential function it effects crossing over not only within the “α-differential” tetrad but also crossing over in non-homologous and unrelated pairs of chromosomes in the same meiotic cell. 16. This hypothesis was ascertained by two independent inversions in autosome 2 (In 2a and In 2b, Fig. 16) which permitted to test the influence of the “α-quantum-difference” in the X-chromosomes on crossing over in the autosome. In preliminary studies the progenies of 8 females (ab, bb, cb) and 3 males (aY, cY) of the heterozygous F1 backcrossed to homozygous b-stock have been investigated. In the progeny of the males only the parental combinations in autosome 2 were found. In the test cross progeny of the females the two expected types of recombination appeared (with only one inversion, In 2a or In 2b), but there existed a very high difference in linkage between bb- ♀♀ on the one side (3.6% crossing over) and ba- and bc-♀♀ on the other (40.2% crossing over).

Notes: Summary A system for monitoring adverse drug reactions (ADR) in psychiatric inpatients was introduced in psychiatric hospitals in the FRG in May 1979. It consists of intensive drug monitoring (IDM) and a so-called “organized spontaneous reporting system” (OSR). ADR are rated separately according to impact on therapy and probability of causal relationship. With IDM all ADR (Grades I–III) are assessed in a randomly selected sample of inpatients. With OSR only ADR leading to discontinuation of the drugs in question (=ADR Grade III) are assessed. In 406 drug-treated inpatients monitored by IDM in the psychiatric hospitals of Berlin and Munich from May 1979 to Dec. 1981, ADR were observed in 60,4%. In 15% of IDM-patients ADR led to discontinuation of the drugs in question; with OSR the relative frequency of these Grade III ADR was 9,0% in 5096 patients monitored throughout the entire period. Life-threatening events were observed in 1,2% of patients undergoing IDM as well as 1.2% of those undergoing OSR. The most frequently observed ADR by IDM were sedation, extrapyramidal signs, disturbances of the autonomic nervous system and increase in transaminases, and by OSR Parkinsonism, akathisia, sedation, toxic delirium and increased transaminases. The relative frequency of Grade III ADR was similar for neuroleptics and antidepressants (5,4% and 5,3% in OSR); a very low relative frequency of ADR Grade III was found for tranquilizers and hypnotics (0,7% and 0,2%). Methodological aspects of this drug monitoring system are discussed in the light of current literature.

Notes: In the preceding papers of this series, it has been shown theoretically and experimentally how the Flory–Huggins interaction parameter χ and the Huggins coefficient kH for polymers differing in molecular weight are built up from the contributions of inter- and intramolecular contacts between polymer segments. In the present work, new experimental material concerning solutions of well-fractionated polyisobutene (PIB) and polystyrene (PS) is presented which, for the first time, includes worse than theta conditions. Its evaluation corroborates the above concept and reveals two features not observed so far. As the solvent quality becomes very unfavorable, the parameters measuring the intermolecular contacts between segments increase as one would expect from the data obtained for good solvent conditions. In contrast to that, the intramolecular parameters no longer decrease smoothly below theta conditions, but show a drastic reduction. This behavior is attributed to coil-collapse phenomena. The second feature concerns the following observation: If the inter- and intramolecular parameters are plotted as a function of the Kuhn–Mark–Houwink exponent, differences in the behavior of PIB and PS become noticeable under certain conditions. These observations are explained by the influence of the particular architecture of the polymer chain.

Notes: The viscosity of the nematic liquid crystal PCH-5 [4-(trans-4′-pentylcyclohexyl)-benzonitrile], measured in the presence of an electric field parallel to the gradient of the velocity, shows a complex dependence both on magnitude E of the electric field and on the shear rate γ(overdot). When plotted versus E2/γ(overdot), all data points fall unto a master curve. In nonequilibrium molecular dynamics computer simulations, performed for a Gay–Berne model fluid, the corresponding influence of a magnetic field on the viscosity was calculated. In both cases, the shape of the master curve for the viscosity can be computed by considering the competition between the torques exerted by the velocity gradient and by the orienting field. It involves the Leslie viscosity coefficients γ1 and γ2, the Miesowicz and Helfrich viscosities η1,η2, and η12. Thus it should be possible to extract these coefficients from the data. This is straightforward in the magnetic case since the molecules in the fluid "see" the externally applied field. The internal electric field, however, differs from the applied field E. When this effect is taken into account, using the known experimental values for dielectric coefficients ε|| and ε⊥, the electro-rheological master curve agrees very well with the experimental data. Values for the viscosity coefficients are obtained and presented. © 2000 American Institute of Physics.

Notes: Various experiments have been performed on a 14.5 GHz ECR4 in order to improve the ion yield. The source runs in pulsed afterglow mode, and provides currents ∼120 eμA of Pb27+ to the CERN Heavy Ion Facility on an operational basis. In the search for higher beam intensities, the effects of a pulsed biased disk on axis at the injection side were investigated with different pulse timing and voltage settings. No proof for absolute higher intensities was seen for any of these modifications. However, the yield from a poorly tuned/low-performing source could be improved and the extracted pulse was less noisy with bias voltage applied. The fast response on the bias implies that increases/decreases are not due to ionization processes. A good tune for high yield of high charge states during the afterglow coincides with a high plasma potential. © 2000 American Institute of Physics.

Notes: A laser ion source using a CO2 laser focused onto a solid target is under study at CERN for the production of high currents of highly charged heavy ions, for possible use in the preinjector for the large hadron collider. A new expansion and extraction layout was installed in this test facility, improving the alignment and making the target to extraction distance more flexible. A two solenoid beam transport system was studied for providing the matching of the beam to a radio-frequency quadrupole. An electrostatic beam transport using gridded electrostatic lenses was designed and constructed as an alternative to a magnetic system. Results show an increased overall current transmission for the electrostatic case. Investigation of the laser parameters required for the production of 1.4×1010 Pb25+ ions in a 5 μs pulse, has been performed using the TIR-1 laser facility at power densities up to 1014 W cm−2 for a focal spot size of 65 μm. The results of the latest scaling are presented. © 2000 American Institute of Physics.