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Notes: Epitaxial Ge films have been deposited on Si and Ge substrates at 300 °C using electron-cyclotron-resonance plasma-assisted chemical vapor deposition. Helium was fed into the resonance chamber, and a mixture of helium and germane were fed downstream at a location above the substrate. Surface roughness increased with energetic ion bombardment as quantified by the number of ions striking the surface per Ge atom deposited. Surface roughness also increased with increasing substrate temperature. Films with very rough surface morphology were found to be polycrystalline. The large hydrogen content of the films, particularly those deposited on Si, appeared to prevent the reduction of the epitaxial temperature below 300 °C. In the temperature range between 300 and 325 °C, hydrogen bubbles formed at the Ge/Si interface and caused the films to pucker from the surface. Increasing the substrate temperature above 325 °C eliminated this problem by decreasing the surface coverage of hydrogen during deposition.

Notes: Granulite facies rocks from the northernmost Harts Range Complex (Arunta Inlier, central Australia) have previously been interpreted as recording a single clockwise cycle of presumed Palaeoproterozoic metamorphism (800–875 °C and 〉9–10 kbar) and subsequent decompression in a kilometre-scale, E-W striking zone of noncoaxial, high-grade (c. 700–735 °C and 5.8–6.4 kbar) deformation. However, new SHRIMP U-Pb age determinations of zircon, monazite and titanite from partially melted metabasites and metapelites indicate that granulite facies metamorphism occurred not in the Proterozoic, but in the Ordovician (c. 470 Ma).The youngest metamorphic zircon overgrowths from two metabasites (probably meta-volcaniclastics) yield 206Pb/238U ages of 478±4 Ma and 471±7 Ma, whereas those from two metapelites yield ages of 463±5 Ma and 461±4 Ma. Monazite from the two metapelites gave ages equal within error to those from metamorphic zircon rims in the same rock (457±5 Ma and 462±5 Ma, respectively). Zircon, and possibly monazite ages are interpreted as dating precipitation of these minerals from crystallizing melt within leucosomes. In contrast, titanite from the two metabasites yield 206Pb/238U ages that are much younger (411±5 Ma & 417±7 Ma, respectively) than those of coexisting zircon, which might indicate that the terrane cooled slowly following final melt crystallization. One metabasite has a second titanite population with an age of 384±7 Ma, which reflects titanite growth and/or recrystallization during the 400–300 Ma Alice Springs Orogeny. The c. 380 Ma titanite age is indistinguishable from the age of magmatic zircon from a small, late and weakly deformed plug of biotite granite that intruded the granulites at 387±4 Ma. These data suggest that the northern Harts Range has been subject to at least two periods of reworking (475–460 Ma & 400–300 Ma) during the Palaeozoic.Detrital zircon from the metapelites and metabasites, and inherited zircon from the granite, yield similar ranges of Proterozoic ages, with distinct age clusters at c. 1300–1000 and c. 650 Ma. These data imply that the deposition ages of the protoliths to the Harts Range Complex are late Neoproterozoic or early Palaeozoic, not Palaeoproterozoic as previously assumed.

Notes: The Mallee Bore area in the northern Harts Range of central Australia underwent high-temperature, medium-to high-pressure granulite facies metamorphism. Individual geothermometers and geobarometers and average P-T calculations using the program Thermocalc suggest that peak metamorphic conditions were 705–810C and 8–12 kbar. Partial melting of both metasedimentary and meta-igneous rocks, forming garnet-bearing restites, occurred under peak metamorphic conditions. Comparison with partial melting experiments suggests that vapour-absent melting in metabasic and metapelitic rocks with compositions close to those of rocks in the Mallee Bore area occurs at 800–875C and 〉9–10 kbar. The lower temperatures obtained from geothermometry imply that mineral compositions were reset during cooling. Following the metamorphic peak, the rocks underwent local mylonitization at 680–730C and 5.8–7.7 kbar. After mylonitization ceased, garnet retrogressed locally to biotite, which was probably caused by fluids exsolving from crystallizing melts. These three events are interpreted as different stages of a single, continuous, clockwise P-T path. The metamorphism at Mallee Bore probably occurred during the 1745–1730 Ma Late Strangways Orogeny, and the area escaped significant crustal reworking during the Anmatjira and Alice Springs events that locally reached amphibolite facies conditions elsewhere in the Harts Ranges.

Notes: Abstract: The effects of several γ-aminobutyric acid (GABA)-ergic drugs on sodium-dependent high-affinity choline uptake (HACU) were investigated in the hippocampus. HACU was measured in vitro after in vivo administration of the drug to mice. HACU was inhibited by those drugs that enhance GABA transmission. The convulsant 3-mercaptopropionic acid, which decreases GABA levels, stimulated HACU. From these results and previous find ings, it appears that GABA mediates a tonic inhibitory effect on the septal-hippocampal cholinergic system.

Notes: Epithelioid haemangiomas are benign, vascular tumours characterized by the proliferation of epithelioid endothelial cells with abundant eosinophilic hyaline cytoplasm. We report a case of epithelioid haemangioma in association with a deep arteriovenous malformation of the subclavian artery. The association of reactive vascular proliferations with arteriovenous malformations is uncommonly reported.

Notes: We describe a 6-year-old girl with severe tinea capitis, who required several months of systemic treatment with griseofulvin, before her condition started to improve with eventual partial hair regrowrh.Kerion refers to the severe inflammatory reaction that occurs in some cases of fungal infection of the hair or hair follicles. The word is derived from the Greek, meaning honeycomb. There is usually a painful, inflamed area studded with pustules, which eventually forms nodules and sinuses. The condition is self-limiting, but even with treatment permanent scarring may ensue.