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Here we explore the diversity of one morphologically distinguishable genus in the Mucoromycotina, Backusella, in south-eastern Australia. We isolated more than 200 strains from locations across the states of Victoria and Tasmania. Characterization of these strains using a combination of approaches including morphology, sucrose utilization and whole genome sequencing for 13 strains, revealed 10 new species. The genetic basis for interspecies variation in sucrose utilization was found to be the presence of a gene encoding an invertase enzyme. The genus Backusella is revised and a new key for species identification produced. Given that we have more than doubled the number of species in this genus, this work demonstrates that there may be considerable undiscovered species diversity in the early diverging fungal lineages. [ABSTRACT FROM AUTHOR]

Spinel-type Fe xCo3− xO4 thin films with x = 0, 1, 2 and 3 were prepared, on stainless steel supports, using the thermal decomposition method at 400 °C. The X-ray diffraction patterns show the presence of a spinel-type structure with a low crystallinity. The electrochemical behaviour was investigated in 1 M KOH, using open-circuit-potential measurements and cyclic voltammetry. The studies allowed to observe the redox reactions occurring at the Fe xCo3− xO4 ( x = 1 and 2) oxide surface, namely Fe3O4/Fe(OH)2 or Fe3O4/Fe2O3, Co3O4/CoOOH, Co(OH)2/CoOOH and CoO2/CoOOH by comparing the experimental data with those obtained for the Co3O4 and Fe3O4 films as well as with those referred to in the literature. The results show that iron ions play the major role in the solid-state surface redox transitions in the negative potential range, whereas the cobalt ions are the key species in the positive potential range. However, the contribution of each component, although small, has to be considered in both potential regions. [ABSTRACT FROM AUTHOR]

Abstract: Fe–Co3O4 thin film with different amounts of Fe have been used for the electro-oxidation of phenol in alkaline medium at room temperature. The electrodes were prepared by coating stainless steel supports with successive layers of the oxides, obtained by thermal decomposition at 673K. The electrolysis was carried out at constant potential and the phenol disappearance, during the electrolysis, was monitored by UV–Vis absorbance measurements between 250 and 500nm. After 3h of electrolysis, the intermediates were identified by comparing the HPLC data and UV–Vis spectra to those from pure standards. The results indicate that the same oxidation products are formed on the different prepared electrodes, namely the decomposition products of phenol such as benzoquinone, hydroquinone and cathecol in basic medium. Simulated results show clearly the decrease of the amount of phenolic species with the electrolysis time. An enhancement of the phenol removal is observed with the presence of iron in the oxide. Under the operating conditions, around 30% of the initial phenol has been removed at ca. 3h and the complete degradation is obtained after 54h of electrolysis, when Fe–Co3O4 thin film with 10% of Fe is used as anode. [Copyright &y& Elsevier]

An electrode kinetic study of oxygen evolution has been made on Li-Co3O4 thin films in KOH aqueous solutions with different concentrations. Oxide films with different amounts of Li were prepared on glass, by chemical spray pyrolysis at 300 °C, followed by a heat treatment at 400 °C in air. The Li doping increases the electrical conductivity of these materials. In what concerns the roughness factor, an increase is also observed up to 3% of Li. From steady-state current–potential measurements, Tafel slopes close to 2.3RT/F were obtained in the low current range, irrespective to electrolyte concentration and Li percentage, pointing to the same oxygen evolution mechanism onto all prepared oxides. The reaction order with respect to OH− was found to be approximately 1.7. The electrodes performance towards the oxygen evolution increases with the increase in Li content. [Copyright &y& Elsevier]

Abstract: Spinel type Fe–Co3O4 (0, 5 and 10% of Fe) adherent and stable films have been prepared on stainless steel supports using the thermal decomposition method at 400°C. All the oxides prepared by this method produced the pure spinel phase. The electrochemical characterization of the catalytic films towards O2-evolution has been made using cyclic voltammetry and ac impedance techniques. The data show that the partial replacement of Co-ion by Fe-ion in the cobalt cobaltite Co3O4 leads to electrodes with lower surface areas. On the other hand, an enhancement of the electrocatalytic activity, towards the oxygen evolution, is confirmed by the values calculated for the corrected Tafel slopes. Values ranging from 71 to 44mV were obtained for the pure and iron containing oxides. The reaction order with respect to OH− concentration was found to be ∼1 on pure and ∼2 on the substituted oxides. [Copyright &y& Elsevier]

A molecular survey of herpesviruses in Australian native mammals was conducted, spanning 260 individuals from 27 species. Among the herpesviruses detected, a putative new gammaherpesvirus species was detected in the yellow-bellied glider (Petaurus australis), and another in the critically endangered Leadbeater's possum (Gymnobelideus leadbeateri). In addition, the known host range of the putative species macropodid gammaherpesvirus 3 (MaHV-3) is herein extended to the western grey kangaroo (Macropus fuliginosus). These findings expand our understanding of herpesviruses in Australian mammals and may inform biosecurity protocols for captive and translocated populations., (© 2022 The Authors. Australian Veterinary Journal published by John Wiley & Sons Australia, Ltd on behalf of Australian Veterinary Association.)

To evaluate the risk of contaminant transport by mobile colloids, it seems essential to understand how colloids and associated pollutants behave during their migration through uncontaminated soil or groundwater. In this study, we investigated at pH 4 the influence of flow velocity, humic acid, solution Ca(2+) concentrations, and trace metals (Pb(2+), Cu(2+)) on the transport and deposition of kaolinite particles through a pure crystalline quartz sand as porous medium. A short-pulse chromatographic technique was used to measure colloid deposition. Adsorption of humic acid to the kaolinite increase its negative surface charge and then decrease colloid deposition. Experiments with different flow rates showed that humic-coated kaolinite colloid deposition followed a first-order kinetic rate law. The deposition rate coefficients of humic-coated kaolinite colloids increase with increasing Ca(2+) concentration in the suspension. The effect of trace metals on the mobility is studied by injecting two suspensions with different concentrations of Pb(2+) and Cu(2+). At very low cation concentration, the fraction of colloids retained is low and roughly independent of the nature of divalent cations. At high concentration, the deposition is higher and depends on the affinity of divalent cations toward humic-coated kaolinite colloids.