Fusarium oxysporum associated with grapevine decline in the Hunter Valley, NSW, Australia

Fusarium oxysporum was isolated from roots of declining grapevines of cv Semillon ( Vitis vinifera L.) in the Hunter Valley, New South Wales. The pathogenicity of the fungus was confirmed by infecting grapevines growing in the glasshouse with material obtained from roots of field-grown vines. The symptoms of the infection on the plants and the effect of the fungus on the roots are described.     

Chromium contamination in black tea and its transfer into tea brew

A survey was conducted in south India to find out the amount of chromium (Cr) present in marketable black tea. Before assessing the Cr content in black tea, the Cr content in the green shoots was assessed, in order to know the Cr contamination after completion of the manufacturing process. Samples of black tea manufactured by CTC (Crush, Tear and Curl) and Orthodox processes were collected and analysed for Cr content. The study revealed that the content of Cr was high in CTC-manufactured black tea, which involved the use of stainless steel rollers. A pilot scale experiment was carried out, using newly sharpened rollers, and the black tea samples prepared were analysed for Cr content. A similar study was carried out in a commercial factory and samples analysed for Cr for one month. The study confirmed that Cr content was positively correlated to the sharpening of CTC rollers used for manufacturing.     

Lipid composition of five species of Indian prawns

The lipid and fatty acid compositions of five Indian species of prawns, Metapenaeus monoceros, M. dobsoni, M. affinis, Penaeus indicus and Parapenaeopsis stylifera, were examined. Phospholipids constituted 50–70% of the total lipids, with phosphatidyl choline (50%) and phosphatidyl ethanolamine (29%) as their chief components. Unsaponifiable matter comprised 21–40%, chiefly cholesterol: triglycerides only constituted 9–14.5%. In the total lipids (I.V. 90–112), saturated, monoenoic and polyenoic fatty acids averaged 42, 24 and 34%. Palmitic acid is high, oleic low, and 20:5 generally, but not always, higher than 22:6. The only brackish water prawn, M. monoceros, though generally in conformity, was distinctive in several respects.     

Triphasic ceramic coated hydroxyapatite as a niche for goat stem cell-derived osteoblasts for bone regeneration and repair

Current treatment strategies for the repair or replacement of bone use synthetic implants with stem cells and their progeny––a new approach to address unmet medical needs. This study has evaluated the effect of a silica-coated bioactive ceramic, namely HASi in comparison to hydroxyapatite (HA) on the adhesion, proliferation and osteogenic differentiation of goat bone marrow-derived mesenchymal stem cells in vitro in a prolonged culture of 28 days. The cellular activities were significantly enhanced on HASi signifying the role of silica to stimulate osteoblast cells. The fabrication of such a ‘cell-ceramic construct using autologous MSCs’ is aimed for the transplantation to a large bone defect site in the goat femur model which still remains a formidable challenge in Orthopedic surgery.     

Fabrication of antiferroelectric PLZT films on metal foils

Fabrication of high-dielectric-strength antiferroelectric (AFE) films on metallic foils is technically important for advanced power electronics. To that end, we have deposited crack-free Pb_0.92La_0.08Zr_0.95Ti_0.05O₃ (PLZT 8/95/5) films on nickel foils by chemical solution deposition. To eliminate the parasitic effect caused by the formation of a low-permittivity interfacial oxide, a conductive buffer layer of lanthanum nickel oxide (LNO) was coated by chemical solution deposition on the nickel foil before the deposition of PLZT. Use of the LNO buffer allowed high-quality film-on-foil capacitors to be processed in air. With the PLZT 8/95/5 deposited on LNO-buffered Ni foils, we observed field- and thermal-induced phase transformations of AFE to ferroelectric (FE). The AFE-to-FE phase transition field, E_AF = 225 kV/cm, and the reverse phase transition field, E_FA = 190 kV/cm, were measured at room temperature on a ≈1.15 μm-thick PLZT 8/95/5 film grown on LNO-buffered Ni foils. The relative permittivities of the AFE and FE states were ≈600 and ≈730, respectively, with dielectric loss ≈0.04 at room temperature. The Curie temperature was ≈210 °C. The thermal-induced transition of AFE-to-FE phase occurred at ≈175 °C. Breakdown field strength of 1.2 MV/cm was measured at room temperature.     

Multielement analysis in cereals and pulses by k0 instrumental neutron activation analysis

The concentrations of some elements in a few varieties of cereals and pulses are determined by Instrumental Neutron Activation Analysis using a single comparator method (k0-standardised NAA method). A total of 15 elements are measured. The method was validated by analysing the Standard Reference Material (SRM-1571) of NIST; the results are within +/-10% of the reported values for the majority of the elements. The measured concentrations of major and minor elements are analysed in terms of the average intake of mineral content and the role of these elements in terms of the nutritional value.     

Experimental Electrohydrodynamic Nanospray Production Using Drawn Glass Capillaries

This article describes a simple and low-cost method of fabricating glass capillary nanospray emitter sources, and, if required, inserting a charging electrode. Initial experimental work employing such a source is described, whose results suggest that whilst the positioning of the charging electrode relative to the orifice influences the charging current and spray considerably, this position may not correspond with that previously reported as being ideal for electrospray systems one or two orders of magnitude greater.     

Defective repair of oxidative damage in mitochondrial DNA in Down''s syndrome

BACKGROUND: Synthetic homopyrimidine peptide nucleic acids (PNAs) can bind complementary targets in double-stranded DNA, generating strand-displacement complexes, and so offering an opportunity to modulate specific gene expression. Several issues remain to be addressed before these attributes can be exploited in vivo, however. RESULTS: The kinetics of the interaction between a homopyrimidine PNA and a complementary homopurine target on double-stranded DNA were analyzed in the presence or absence of a preformed strand-displacement complex proximal to the target. The complex was established under low salt conditions by the binding of a different homopyrimidine PNA to a target situated adjacent to the first PNA target. These two targets were placed next to each other on opposite strands at distances of 0, 2, 4 and 8 base pairs apart. The presence of a preformed strand-displacement complex near the target accelerates the binding of PNA to double-stranded DNA in a salt-dependent manner. The influence of salt on the binding rates was also examined. The binding rate is increased by a factor of 1 x exp(70[NaCl]), that is, 16-fold at 40 mM NaCl and more than 10(4)-fold if extrapolated to 140 mM NaCl. This effect is significantly reduced if the two targets are 2 base pairs apart and completely absent if the distance is 4 base pairs or more. CONCLUSIONS: The perturbation of the DNA helix imposed by a PNA strand-displacement complex only propagates a few base pairs. It is therefore possible to target sites in the immediate vicinity of strand invasion complexes specifically. The results presented have implications for the mechanism of strand displacement and for the application of PNA in a genomic context.     

Ba2HoNbO6: A new perovskite ceramic substrate for superconducting YBa2Cu3O7−δ thick film (T c (0) = 92 K)

A complex perovskite oxide Ba₂HoNbO₆ has been developed as a non-reacting substrate for YBa₂Cu₃O_7– superconducting film with lattice constant a = 8.3905 Å. The dielectric constant (30) and loss factor value (5 × 10^–3) of the material are in the range suitable for its use as substrate for microwave applications. A YBa₂Cu₃O_7–delta; superconducting thick film dip coated on Ba₂HoNbO₆ substrate gave a T _c(0) of 92 K and current density of 1.2 × 10⁴ A cm^–2.     

Effect of low-density filler on mechanical properties of syntactic foams of cyanate ester

Syntactic foam composites of cyanate ester with varying volume fractions of resin and glass microballoon were processed and evaluated for tensile, flexural and compressive properties. The effect of nature and volume fraction of microballoon on the mechanical properties was studied. The mechanical properties showed a gradual decrease in strength with increase in volume fraction of microballoon. The specific strength values also manifested a similar order. A similar behaviour was observed for syntactic foams with microballoons of varying true density. The properties increased proportional to the strength of the microballoon in resin-rich systems implying a strong microballoon-resin interface, corroborated by Scanning Electron Microscopy studies. The compressive modulus showed a decreasing trend with enhanced microballoon loading.