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The oxidative modification of proteins has been shown to play a major role in a number of human diseases. However, the ability to identify specific proteins that are most susceptible to oxidative modifications is difficult. Separation of proteins using polyacrylamide gel electrophoresis (PAGE) offers the analytical potential for the recovery, amino acid sequencing, and identification of thousands of individual proteins from cells and tissues. We have developed a method to allow underivatized proteins to be electroblotted onto PVDF membranes before derivatization and staining. Since both the protein and oxidation proteins are quantifiable, the specific oxidation index of each protein can be determined. The optimal sequence and conditions for the staining process are (a) electrophoresis, (b) electroblotting onto PVDF membranes, (c) derivatization of carbonyls with 2,4-DNP, (d) immunostaining with anti DNP antibody, and (e) protein staining with colloidal gold.

Abundant and well-preserved material of the ligulate lycopsid genus Leclercqia is reported from a new Middle Devonian locality in northeastern Queensland (Australia). The plants occur in a chert horizon in the Storm Hill Sandstone of the Dosey-Craigie Platform. Lithological data and conodont analyses combined with information from in situ spores provide an age for the plant levels ranging from Eifelian, possibly Middle Eifelian, to Early Givetian. Plant taxonomic identification is based on vegetative and fertile stems that display both external morphology and anatomy. This material represents the best documented occurrence of Leclercqia outside Laurussia and possibly the earliest in Gondwana; it provides evidence that colonization of Gondwana by the species L. complexa was contemporaneous to that of Siberia and Kazakhstan. Analysis of the distribution patterns of L. complexa suggests that it was adapted to a wide range of environments, but within certain limits which we hypothesize to be those of a climatic belt. Such considerations support previous studies using other biological data, such as faunas and palynomorphs, for reconstructing Devonian palaeogeography. They favour a close proximity of Laurussia and Gondwana rather than the occurrence of a wide ocean separating the two palaeocontinents in Middle Devonian times. Keywords: Australia, Devonian, Gondwana, Lycopsida, palaeogeography.

Francis M. Hueber was an important figure in mid- and late twentieth-century paleobotany; a specialist in Devonian plants, he focused his research on a much broader array of topics. Here we briefly describe his early life and education, outline his 40-year career at the Smithsonian National Museum of Natural History (NMNH) in Washington, DC, and review some of his most important publications, most significantly on the once-enigmatic Devonian fossil Prototaxites. We review his important field expeditions and contributions to the collections in the Department of Paleobiology of the NMNH and his educational activities at the NMNH. Finally, some personal reminiscences are presented. [ABSTRACT FROM AUTHOR]

Described is an acid-leaching facility at Macquarie University in Australia for teaching paleontology. The facility is used for teaching both undergraduate and graduate students and for research by staff and graduate students. Drawings of the facility are included and courses are described. (Author/RH)

Late Silurian and Early Devonian conodonts are documented from outcropping limestones at nine Cobar Supergroup localities: the Booth Limestone, the Mountain Dam Limestone, the Beloura Tank Limestone Member of the Baledmund Formation, the “Lerida Limestone Member” of the Amphitheatre Group, and limestones in Stoney Creek in the Gundabooka National Park, in the Troffs Formation in the Trundle Group and in the Derriwong Group at Myola. These (with the exception of Myola) and conodonts previously documented from the White Tank and Rookery limestone members of the Meryula Formation are Pragian in age, ranging from sulcatus Zone to the imprecisely defined pireneae Zone, with the uppermost part of one of them (the Booth Limestone) possibly extending into the earliest Emsian. The Derriwong Group carbonates are late Ludfordian, crispa Zone, in age and are the only remnants discovered to date of a Silurian marine incursion. Ages for the Devonian limestones are: Booth Limestone, late in the sulcatus Zone to “pireneae Zone” with the uppermost horizon possibly extending into the dehiscens Zone; Mountain Dam Limestone, sulcatus Zone with the uppermost preserved horizon inferred to have been late in the sulcatus Zone; the Beloura Tank Limestone Member, sulcatus Zone; the ?olistoliths constituting the “Lerida Limestone Member”, sulcatus Zone; and limestones in Stoney Creek in the Gunderbooka National Park, “pireneae Zone”. Conodonts previously documented from “The Rookery” - the White Tank and Rookery limestone members - are inferred to be sulcatus Zone. In terms of recently refined absolute ages, Devonian carbonate sedimentation in the Cobar Supergroup, though localised, thus spans a six-or-seven-million-year time slice. The Devonian limestones investigated were apparently deposited during a single, basin-wide sedimentary event that was conducive to accumulation of carbonate sediments at various loci. Several conodont species documented here are taxa found in Central Asia and Arctic North American localities. Previous examples of such apparent provincialism, based on conodont distribution, have been noted to occur in faunas from the pesavis and kindlei zones, the imprecisely defined pireneae interval, and now for the sulcatus Zone. A plethora of new species and subspecies identified from the Cobar Supergroup limestones appear in the middle to late portion of the sulcatus Zone, an interval from which conodonts have not been documented as copiously as from other time slots globally. New conodont taxa consist of one new genus, eight new species - one kept in open nomenclature - and six new subspecies: Heliagnathus gen. nov. (type species Heliagnathus parvilabiatus sp. nov.), Panderodus rhytiodus sp. nov., Panderodus sp. nov. A, Icriodus ampliatus sp. nov., Pelekysgnathus inaequalis sp. nov., Oulodus astriatus sp. nov., Ozarkodina multistriola sp. nov., Ozarkodina scoliciformis sp. nov., Amydrotaxis corniculans truncus subsp. nov., Eognathodus sulcatus lanei subsp. nov., Eognathodus sulcatus sicatus subsp. nov., Ozarkodina selfi lenticula subsp. nov., Ozarkodina selfi lanceola subsp. nov. and Ozarkodina selfi cordata subsp. nov. Biostratigraphic data from this study indicate a separation in the ranges of Ozarkodina selfi and Eognathodus sulcatus. A polyphyletic origin of Eognathodus is suggested. Biometric data are presented to demonstrate that Icriodus ampliatus sp. nov. occupies a morphological gap between I. steinachensis and I. claudiae and its first appearance is a marker of the upper sulcatus zone. [ABSTRACT FROM AUTHOR]