Systematic relationships of some members of the genera Oesophagostomum and Chabertia (Nematoda: Chabertiidae) based on ribosomal DNA sequence data

The present study characterised seven species of the Chabertiidae (Nematoda: Strongyloidea) belonging to either the subfamily Oesophagostominae (Oesophagostomum radiatum, Oesophagostomum venulosum, Oesophagostomum dentatum, Oesophagostomum quadrispinulatum, Oesophagostomum columbianum, Oesophagostomum bifurcum) or to the subfamily Chabertiinae (Chabertia ovina) by their second internal transcribed spacer rDNA sequence, assessed the extent of intraspecific variation and interspecific differences in the sequence, and inferred the phylogenetic relationship of C. ovina with respect to members of the Oesophagostominae. In both the phenetic and cladistic analyses of the sequence data, Chabertia was nested within Oesophagostomum, suggesting either that the species examined represent members of the same genus, or alternatively, that Oesophagostomum may represent more than one genus.     

"Candidatus phytoplasma australiense," a new phytoplasma taxon associated with Australian grapevine yellows

A phytoplasma was detected in naturally diseased 'Chardonnay' grapevines exhibiting symptoms of Australian grapevine yellows disease. The use of PCR designed to amplify phytoplasma DNA resulted in detection of phytoplasma DNA in all of the diseased plants examined; no phytoplasma DNA was detected in healthy seedling grapevines. The collective restriction fragment length polymorphism (RFLP) patterns of amplified 16S ribosomal DNA differed from the patterns described previously for other phytoplamas. On the basis of the RFLP patterns, Australian grapevine yellows phytoplasma was classified as a representative of a new subgroup, designated subgroup 16SrI-J, in phytoplasma 16S rRNA group 16SrI (aster yellows and related phytoplasmas). A phylogenetic analysis in which parsimony of 16S rRNA gene sequences from this and other group 16SrI phytoplasmas was used identified the Australian grapevine yellows phytoplasma as a member of a distinct subclade (subclade xii) in the phytoplasma clade of the class Mollicutes. A phylogenetic tree constructed on the basis of 16S rRNA gene sequences was consistent with the hypothesis that there was divergent evolution of Australian grapevine yellows phytoplasma and its closet known relative, European stolbur phytoplasma (subgroup 16SrI-G), from a common ancestor. The unique properties of the DNA from the Australian grapevine yellows phytoplasma clearly establish that it represents a new taxon, "Candidatus Phytoplasma australiense."     

Concurrent invaders--four exotic species of Monogenea now established on exotic freshwater fishes in Australia

Four species of exotic monogeneans are reported from five species of exotic freshwater fish in Australia: Gytrodactylus bullatarudis from Poecilia reticulata and Xiphophorus helleri in Queensland; Gyrodactylus macracanthus from Misgurnus anguillicaudatus in the Australian Capital Territory; Dactylogyrus extensus from Cyprinus carpio in the Australian Capital Territory; and Dactylogyrus anchoratus from Carassius auratus in the Australian Capital Territory. This is the first published record of described species of monogeneans of the genus Dactylogyrus or Gyrodactylus from Australia and the first report of parasites of M. anguillicaudatus in Australia. The establishment of exotic monogenean populations on Australian native fishes via host-switching is considered less likely than for other parasitic groups due to the generally high host-specificity of monogeneans, combined with the phylogenetic dissimilarity of native and exotic fishes. Similar establishments have occurred elsewhere, however, and the risk of these events increases with each new fish species introduction.     

Biogeographic origins of goannas (Varanidae): a molecular perspective

This project aims to clarify the phylogenetic relationships among the extant species of Varanus in order to elucidate the origins of Varanidae, using DNA sequences. Results obtained for a minimum of 662 nucleotides of 12S rRNA sequence data from each of 21 extant species of Varanus indicate that the Australian varanids form a single monophyletic clade and also suggest that within the Australian varanids, members of the subgenus Odatria (pygmy monitors) may from a clade separate from those in the subgenus Varanus (large monitors). The Asian species appear to be sister taxa to the Australian species, while the two African species investigated were most divergent, suggesting that the Varanidae are not Gondwanic in origin. Hypothesis testing analyses were performed and involved constraining the 12S sequence data according to previously described topologies and testing the difference using parametric and nonparametric statistics. The phylogeny generated using 12S sequence data was statistically different from previously described morphological trees, while there was some support for topologies based on chomosomal and immunological datasets. Overall, our results suggest that the Australian species may be derived from an Asian source and are, therefore, in agreement with the hypothesis based on the fossil record suggesting that Varanidae may be Asian in origin.     

Actions of cyclic esters, S-esters, and amides of phenyl- and phenylthiophosphonic acids on mammalian and insect GABA-gated chloride channels

We undertook a comprehensive phylogenetic study to establish the genetic relationship among the viruses of the genus Flavivirus and to compare the classification based on molecular phylogeny with the existing serologic method. By using a combination of quantitative definitions (bootstrap support level and the pairwise nucleotide sequence identity), the viruses could be classified into clusters, clades, and species. Our phylogenetic study revealed for the first time that from the putative ancestor two branches, non-vector and vector-borne virus clusters, evolved and from the latter cluster emerged tick-borne and mosquito-borne virus clusters. Provided that the theory of arthropod association being an acquired trait was correct, pairwise nucleotide sequence identity among these three clusters provided supporting data for a possibility that the non-vector cluster evolved first, followed by the separation of tick-borne and mosquito-borne virus clusters in that order. Clades established in our study correlated significantly with existing antigenic complexes. We also resolved many of the past taxonomic problems by establishing phylogenetic relationships of the antigenically unclassified viruses with the well-established viruses and by identifying synonymous viruses.     

A molecular phylogeny of the family Mustelidae (Mammalia, Carnivora), based on comparison of mitochondrial cytochrome b nucleotide sequences

To study the phylogenetic relationships between the species of the family Mustelidae, by using the improved polymerase chain reaction-product direct sequencing technique, nucleotide sequences (375 bases) of the mitochondrial cytochrome b gene were determined on ten species from five genera of the Mustelidae and three species of other carnivore families, all of which are distributed in or around Japan. The molecular phylogenetic tree indicated a clear separation of five genera: Mustela and Martes from the subfamily Mustelinae, Lutra and Enhydra from the subfamily Lutrinae, and Meles from the subfamily Melinae. This clustering agreed with the previously reported morphological and karyological taxonomy. Furthermore, the relationships between the intrageneric species were discussed in more detail. This is the first report on the molecular phylogeny throughout the Japanese species of the Mustelidae, inferred from the mitochondrial DNA sequences.     

X-ray structures and analysis of 11 cyclosporin derivatives complexed with cyclophilin A

The mitochondrial D-loop hypervariable segment 1 (mt HVS1) between nucleotides 15997 and 16377 has been examined in aboriginal Australian people from the Darling River region of New South Wales (riverine) and from Yuendumu in central Australia (desert). Forty-seven unique HVS1 types were identified, varying at 49 nucleotide positions. Pairwise analysis by calculation of BEPPI (between population proportion index) reveals statistically significant structure in the populations, although some identical HVS1 types are seen in the two contrasting regions. mt HVS1 types may reflect more-ancient distributions than do linguistic diversity and other culturally distinguishing attributes. Comparison with sequences from five published global studies reveals that these Australians demonstrate greatest divergence from some Africans, least from Papua New Guinea highlanders, and only slightly more from some Pacific groups (Indonesian, Asian, Samoan, and coastal Papua New Guinea), although the HVS1 types vary at different nucleotide sites. Construction of a median network, displaying three main groups, suggests that several hypervariable nucleotide sites within the HVS1 are likely to have undergone mutation independently, making phylogenetic comparison with global samples by conventional methods difficult. Specific nucleotide-site variants are major separators in median networks constructed from Australian HVS1 types alone and for one global selection. The distribution of these, requiring extended study, suggests that they may be signatures of different groups of prehistoric colonizers into Australia, for which the time of colonization remains elusive.     

Experimental Study of Dry Desliming Iron Ore Tailings by Air Classification

ABSTRACT

Techniques for dry processing low-grade iron ores and tailings are being investigated. Dry desliming tests using a rotating wheel air classifier and factorial design were performed on a difficult-to-treat low-grade high-goethite Australian iron ore tailings. The results were compared with theoretically ideal size separation and a hydrocyclone desliming study using the same tailings. The air classifier performance was poorer than the hydrocyclone due to agglomerated particles in the feed, including fines coating coarser particles. The “fish hook” effect was observed and discussed. After dry desliming, the silica and alumina contents of a selected product were 30% and 26% lower, respectively.     

Life transitions and mental health in a national cohort of young Australian women.

Young adulthood, a time of major life transitions and risk of poor mental health, may affect emotional well-being throughout adult life. This article uses longitudinal survey data to examine young Australian women's transitions across 4 domains: residential independence, relationships, work and study, and motherhood. Changes over 3 years in health-related quality of life, optimism, depressive symptoms, stress, and life satisfaction, were examined in relation to these transitions among 7,619 young adult participants in the nationally representative Australian Longitudinal Study on Women's Health. Positive changes in mental health occurred for women moving into cohabitation and marriage, whereas reductions were observed among those experiencing marital separation or divorce and those taking on or remaining in traditionally "feminine" roles (out of the workforce, motherhood). The data suggest that women cope well with major life changes at this life stage, but reductions in psychological well-being are associated with some transitions. The findings suggest that preventive interventions to improve women's resilience and coping might target women undergoing these transitions and that social structures may not be providing sufficient support for women making traditional life choices. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Feasibility study of the new rutile extraction process from natural ilmenite ore based on the oxidation reaction

Phase relations in the Fe₂O₃-FeTiO₃-TiO₂ system were investigated by equilibrating synthetic samples in evacuated sealed quartz tubes at a temperature of 1373 K. The equilibrium partial pressure of oxygen was measured by the electromotive force (EMF) method in the temperature range of 1273 to 1373 K. The phase diagram and oxygen partial pressure diagram in the titanium-iron-oxygen ternary system were then constructed at 1373 K. Rutile extraction from natural ilmenite ore was discussed from the thermodynamic viewpoint. It is found that rutile can be produced from common natural ilmenite ores not only by the reduction as the conventional titanium-rich slag process but also by an oxidation. Then, the oxidation experiment was conducted in air using Australian ilmenite ore to obtain rutile as one of the coexistent phases. Magnetic separation and leaching experiments for synthesized pseudobrookite and reagent rutile were conducted to confirm the possibility of separation of rutile from pseudobrookite. A new rutile extraction process was then proposed.     

Amino acid sequences of hemoglobin beta chains of five species of pinnipeds: Neophoca cinerea, Otaria byronia, Eumetopias jubatus, Pusa hispida, and Pagophilus groenlandica

Pinnipeds (Otariidae, Odobenidae, and Phocidae) in the order Carnivora have one or two types (Hb I and Hb II) of hemoglobin components. These hemoglobins consist of identical beta chains and different alpha chains. We determined the complete amino acid sequences of the hemoglobin beta chain of three species of Otariidae (Australian sea lion, South American sea lion, and northern sea lion) and two species of Phocidae (ringed seal and harp seal) from intact beta chain and chemical cleavage fragments. The sequences are similar to beta chains of the already known sequences of pinnipeds. These sequences were compared with those of other carnivores (Mustelidae, Ursidae, Canidae, and Felidae) and adult human hemoglobin beta chain. Using Artiodactyla (pig) as an outgroup, we find that the tree constructed by means of phylogenetic analysis shows that Odobenidae is closest to Otariidae, and that Otariidae and Odobenidae are closer to Mustelidae than to Phocidae.     

The origin of the dog-like borhyaenoid marsupials of South America

Dog-like marsupials (superfamily Borhyaenoidea) were the largest predacious mammals during the Tertiary period in South America. They are critical to our understanding of marsupial origin, phylogeny and palaeobiogeography because they have been related to various marsupial lineages of several continents: didelphoids (mainly New World, but also Europe, Asia and Africa), pediomyid, stagodontids (North America), dasyuroids (Australia) and deltatheroidans (predominantly Asian). These relationships, based mainly on dental morphology, have been discussed and rejected several times. Here we report the discovery of exceptionally well preserved skulls and skeletons, referrable to the didelphoid Andinodelphys, which shed new light on the phylogenetic and palaeobiogeographic origin of dog-like marsupials. The skulls of Mayulestes (boryhyaenoid), Andinodelphys and Pucadelphys (didelphoids) from the early Palaeocene epoch of Bolivia are the oldest known for American marsupials. Comparison of their basicranial anatomy suggests that dog-like marsupials are closely related to an early didelphimorphian radiation in South America, rather than to Asiatic (deltatheroidan), North American (stagodontid), or Australian (dasyuroid) lineages.     

Relationships in the Drosophila obscura species group, inferred from mitochondrial cytochrome oxidase II sequences

We compare the sequences for the mitochondrial cytochrome oxidase II gene of 13 species of the Drosophila obscura group. The survey includes six members of the D. affinis subgroup, four of the D. pseudoobscura subgroup, and three of the D. obscura subgroup. In all species, the gene is 688 nucleotides in length, encoding a protein of 229 amino acids plus the first position T of the stop codon. The sequences show the typical high-transition bias for closely related species, but that bias is essentially eliminated for species pairs of > 5% sequence divergence. The phylogenetic relationships in the species group are inferred using both neighbor-joining and maximum parsimony. The two procedures give comparable results, showing that the D. affinis and D. pseudoobscura subgroups are monophyletic groupings that appear to have closer affinities to one another than either has to the D. obscura subgroup. We use transversion distances to estimate times of divergence, on the basis of three different estimates of the time of separation of the D. obscura species group from the D. melanogaster group. If that event occurred 35 Mya, then we can estimate the origin of the nearctic forms at approximately 22 Mya and the separation of the D. affinis and D. pseudoobscura subgroups at approximately 17 Mya.     

褐铁矿配加澳矿的烧结效果

对褐铁矿配加澳在利亚矿进行了烧结试验。研究表明：与褐铁矿相比,澳大利亚矿适合于低水、低碳烧结。对碱度为２．０的烧结矿,配加３０－４０％的澳矿,其烧结效果最佳。     

Evolution of acid phosphatase-1 in the genus Drosophilia. Immunological studies

The enzyme acid phosphatase-1 was partially purified from 10 Drosophila species. Four antisera were produced and the ten enzymes were reacted against each serum. The method used to quantitate the reactions involved the electrophoretic separation of antigen-antibody complexes from uncomplexed enzyme, followed by densitometry of the free enzyme. Immunological distances were used to obtain correlation coefficients for all pairwise combinations of the 10 species. From these correlation coefficients, a dendrogram was constructed which is very similar to one diagramming the presumed phylogenetic relationships of the ten species. In addition, the data indicate acid phosphatase-1 has evolved at different rates in different lineages within the genus. A preliminary estimate of the unit evolutionary period for this enzyme is 3.25 million years. The method of determining immunological distances which was used in this study is compared to the method of microcomplement fixation in the Discussion.     

Innate immunity. Isolation of several cysteine-rich antimicrobial peptides from the blood of a mollusc, Mytilus edulis

We have isolated from the blood of immune-challenged and untreated mussels (Mytilus edulis) antibacterial and antifungal peptides. We have characterized two isoforms of a novel 34-residue, cysteine-rich, peptide with potent bactericidal activity and partially characterized a novel 6.2-kDa antifungal peptide containing 12 cysteines. We report the presence of two members of the insect defensin family of antibacterial peptides and provide a phylogenetic analysis that indicates that mollusc and arthropod defensins have a common ancestry. Our data argue that circulating antimicrobial peptides represent an ancient host defense mechanism that predated the separation between molluscs and arthropods at the root of the Cambrian, about 545 million years ago.     

Sequence variations in small-subunit ribosomal RNAs of Hartmannella vermiformis and their phylogenetic implications

Evidence of associations between free-living amoebas and human disease has been increasing in recent years. Knowledge about phylogenetic relationships that may be important for the understanding of pathogenicity in the genera involved is very limited at present. Consequently, we have begun to study these relationships and report here on the phylogeny of Hartmannella vermiformis, a free-living amoeba that can harbor the etiologic agent of Legionnaires' disease. Our analysis is based on studies of small-subunit ribosomal RNA genes (srDNA). Nucleotide sequences were determined for nuclear srDNA from three strains of H. vermiformis isolated from the United Kingdom, Germany, and the United States. These sequences then were compared with a sequence previously obtained for a North American isolate by J. H. Gunderson and M. L. Sogin. The four genes are 1,840 bp long, with an average GC content of 49.6%. Sequence differences among the strains range are 0.38%-0.76%. Variation occurs at 19 positions and includes 2 single-base indels plus 14 monotypic and 3 ditypic single-base substitutions. Variation is limited to eight helix/loop structures according to a current model for srRNA secondary structure. Parsimony, distance, and bootstrap analyses used to examine phylogenetic relationships between the srDNA sequences of H. vermiformis and other eukaryotes indicated that Hartmannella sequences were most closely related to those of Acanthamoeba and the alga Cryptomonas. All ditypic sites were consistent with a separation between European and North American strains of Hartmannella, but results of other tests of this relationship were statistically inconclusive.     

Sequence of the non-phosphorylating glyceraldehyde-3-phosphate dehydrogenase from Nicotiana plumbaginifolia and phylogenetic origin of the gene family

A cDNA-library has been constructed from Nicotiana plumbaginifolia seedlings, and the non-phosphorylating glyceraldehyde-3-phosphate dehydrogenase (GapN, EC 1.2.1.9) was isolated by plaque hybridization using the cDNA from pea as a heterologous probe. The cDNA comprises the entire GapN coding region. A putative polyadenylation signal is identified. Phylogenetic analysis based on the deduced amino acid sequences revealed that the GapN gene family represents a separate ancient branch within the aldehyde dehydrogenase superfamily. It can be shown that the GapN gene family and other distinct branches of the superfamily have its phylogenetic origin before the separation of primary life-forms. This further demonstrates that already very early in evolution, a broad diversification of the aldehyde dehydrogenases led to the formation of the superfamily.     

Mitochondrial ND1 gene sequences used to identify echinostome isolates from Australia and New Zealand

Echinostomes were collected in Australia and New Zealand as cercariae, metacercariae or adults. Using DNA sequences from the mitochondrial ND1 gene Echinostoma revolutum and Echinostoma paraensei were discovered in Australia. The presence of a further five, as yet unidentified, echinostome species was inferred in Northern Australia and a further isolate, closely allied to E. revolutum, occurs in New Zealand. ND1 sequences of species within the genus diverge from each other by 9.6-30.8%. Sequence divergence levels among strains within a single species are 0-3.6%. The phylogenetic tree produced from the Australasian isolates, in addition to species described previously, identifies the 37-collar-spine species as a well supported monophyletic group. The five unidentified Australian species cluster away from the 37-collar-spine group. These unidentified species appear to divide further into > 37-collar-spine and < 37-collar-spine clusters. Three strains of E. revolutum, collected as metacercariae from snails, were identified from two ponds located 6 km apart. Two of these strains may be cycling through a planorbid snail, Glyptophysa sp., as first intermediate host; however, this hypothesis could not be confirmed as specimens could not be obtained to match sequences between larvae and adults.