Worldwide forest surveys reveal forty-three new species in Phytophthora major Clade 2 with fundamental implications for the evolution and biogeography of the genus and global plant biosecurity

During 25 surveys of global Phytophthora diversity, conducted between 1998 and 2020, 43 new species were detected in natural ecosystems and, occasionally, in nurseries and outplantings in Europe, Southeast and East Asia and the Americas. Based on a multigene phylogeny of nine nuclear and four mitochondrial gene regions they were assigned to five of the six known subclades, 2a-c, e and f, of Phytophthora major Clade 2 and the new subclade 2g. The evolutionary history of the Clade appears to have involved the pre-Gondwanan divergence of three extant subclades, 2c, 2e and 2f, all having disjunct natural distributions on separate continents and comprising species with a soilborne and aquatic lifestyle and, in addition, a few partially aerial species in Clade 2c; and the post-Gondwanan evolution of subclades 2a and 2g in Southeast/East Asia and 2b in South America, respectively, from their common ancestor. Species in Clade 2g are soilborne whereas Clade 2b comprises both soil-inhabiting and aerial species. Clade 2a has evolved further towards an aerial lifestyle comprising only species which are predominantly or partially airborne. Based on high nuclear heterozygosity levels ca. 38 % of the taxa in Clades 2a and 2b could be some form of hybrid, and the hybridity may be favoured by an A1/A2 breeding system and an aerial life style. Circumstantial evidence suggests the now 93 described species and informally designated taxa in Clade 2 result from both allopatric non-adaptive and sympatric adaptive radiations. They represent most morphological and physiological characters, breeding systems, lifestyles and forms of host specialism found across the Phytophthora clades as a whole, demonstrating the strong biological cohesiveness of the genus. The finding of 43 previously unknown species from a single Phytophthora clade highlight a critical lack of information on the scale of the unknown pathogen threats to forests and natural ecosystems, underlining the risk of basing plant biosecurity protocols mainly on lists of named organisms. More surveys in natural ecosystems of yet unsurveyed regions in Africa, Asia, Central and South America are needed to unveil the full diversity of the clade and the factors driving diversity, speciation and adaptation in Phytophthora

Antimicrobial activity of natural soaps tested by Bioscreen methodology

The aim of this study was to combine the utilization of waste frying oils within soap making process in order to make useful and environmentally friendly solutions and development of methods for determination of the antimicrobial effect of those created products. Soaps were made from edible oils which are fried in laboratory conditions. The antimicrobial activity of soaps was done against Staphylococcus aureus species as one of the representatives of the human skin microbiome. Two methods were applied: agar dilution method and the method including kinetics following on Bioscreen micro­biology reader. In the first method, the number of CFU was followed on agar medium with and without different soap solutions after incubation for 24 hours at 30 °C. The result for IC50 (inhibition concentration for 50% of population) was 0.08 mg/mL. Minimal inhibition concentration was detected at 0.41 mg/mL and minimal bactericidal concentration was observed at > 0.75 mg/mL for selected soap solution. Soap concentrations of 0.3 mg/mL of soaps (made from fresh and fried oil) were used for Bioscreen assessment with measurement on every hour during the 7 hours of incubation at 30 °C. 5-second sequence of shaking of the microplate was applied before each measurement which was done at the wavelength of 610 nm. The growth coefficients of the culture with soap solutions added and from the growth of culture only were compared. The growth of S. aureus subjected to soaps made from fresh and fried oils was inhibited 55.3% and 69.7% respectively against the control during the first seven hours of incubation. From results obtained, it was concluded that there is a great potential of the Bioscreen as a method for further studies on antibacterial activity of soaps made from waste frying oils

Experts system based on the neural network and mobile database in the field galvanic metal coating

© 2018 Published by Faculty of Engineering. In a modern era of information technologies, everyday changes are more numerous and various. One of those changes is related to the greater use of mobile devices in a decision making processes. They may be used in the field of automation and improvement of production processes. Their main purpose may be seen as the achievement of optimal production quality, lower production costs, timely deliveries, rational management of material and information flows. Having this in mind, it may be said that interactive data processing from different data sources and the application of artificial intelligence methods is possible within the field of metal coating data processing and prediction. In this paper, novel developed model and expert system, which consists of mobile databases and neural network for the prediction of quality of coating has been presented. Input data obtained from the databases are related to the starting conditions of deposition and the quality of the given coating material, while the target data are related to the thickness and roughness of the material surfaces. Application of the presented solution may confirm the possibility of integration of mobile databases and neural networks within a mobile expert system in the field of modern production systems

Synthetic access to a framework-stabilized and fully sulfided analogue of an Anderson polyoxometalate that is catalytically competent for reduction reactions

Polyoxometalates (POMs) featuring 7, 12, 18, or more, redox-accessible transition-metal ions are ubiquitous as selective catalysts, electrocatalysts, and sensitized photocatalysts, especially for oxidation reactions. The corresponding synthetic and catalytic chemistry of stable, discrete, and capping-ligand-free polythiometalates (PTMs), which could be especially attractive for reduction reactions, is much less well developed. Among the challenges is the propensity of PTMs to agglomerate and form larger clusters of indeterminate size, as well as the tendency for agglomeration to block access of candidate reactants to potential catalyst active-sites. Nevertheless, the pervasive presence of transition-metal sulfur clusters metalloenzymes or cofactors that catalyze reduction reactions, and the justifiable proliferation of studies of 2D metal chalcogenides, and especially their edge sites, as reduction catalysts, point to the promise of well-defined and controllable PTMs as catalysts for reduction reactions, including complex, bond-forming, many-electron reactions. Here we report the fabrication of agglomeration-immune, reactant-accessible, capping-ligand-free CoIIMoIV6S24n- clusters as periodic arrays in a water-stable, hierarchically porous Zr-metal-organic-framework (MOF; NU1K) by first preparing and installing a disk-like Anderson polyoxometalate, CoIIMoVI6O24m(-), in size-matched (<1 nm) micropores termed c-pores, where the siting is established via DED (difference electron density) X-ray diffraction experiments. Prolonged treatment with flowing H2S while heating, uniformly reduces the six molybdenum(VI) ions to Mo(IV) and quantitatively replaces oxygen anions with similarly ligating sulfur anions in the form S(2-), HS(-), and S2(2-). Further DED measurements show that the templated POM-to-PTM conversion leaves the clusters individually isolated in open-channel-connected c-pores. The structure of the immobilized cluster as determined, in part, by XPS, XAFS, and PDF (pair-distribution function) analysis of total X-ray scattering agrees very well with the theoretically simulated structure. Preliminary, proof-of-concept experiments show that electrode-supported thin-films of CoMo6S24@NU1K are electrocatalytically competent for hydrogen evolution in aqueous acid (e.g. 10 mA·cm-2 of current density at an overpotential of 100 mV). Suspensions of CoMo6S24@NU1K in acetonitrile + triethanolamine, are photocatalytically competent for hydrogen evolution via sensitization with chromophoric MOF linkers. Nevertheless, the initially installed PTM appears to be a pre-catalyst, as hydrogen evolution is observed only after four hours of photolysis. Reduction-assisted loss of ~3-to-6 sulfurs, as H2S, likely is responsible for pre-catalyst-to-catalyst conversion, as the loss opens coordination sites on multiple cluster-sited metal ions, perhaps enabling hydrogen evolution via a Mo-hydride intermediate. Given the great variety of sizes and compositions available for both POMs and Zr-MOFs, we suggest that the approach described here can be adapted for the synthesis and stabilization of periodic arrays of other non-agglomerating, capping-ligand-free PTMs of well-defined metal-nuclearity, presumably including catalytically functional PTMs

Synchrotron X-ray absorption spectroscopy and X-ray powder diffraction studies of the structure of johnbaumite [Ca-10(AsO4)(6)(OH,F)(2)] and synthetic Pb-, Sr- and Ba-arsenate apatites and some comments on the crystal chemistry of the apatite structure type in general

The chemical composition oft he natural arsenate-apatite mineral johnbaumite [nominally Ca10(AsO4)6(OH)2] and its alteration product hedyphane [Ca4Pb6(AsO4)6Cl2] have been determined by electron microprobe analysis and the structures ofjohnbaumite and synthetic Sr-, Ba- and Pbarsenate apatites have been studied by As K-edge X-ray absorption spectroscopy and synchrotron X-ray powder diffraction. All samples belong to the holosymmetric apatite space group P63/m with As5+ substituted for P5+ in the tetrahedral structural site. Johnbaumite contains small amounts ofF and Pb (~0.9 and ~4.4 wt.% respectively) and hedyphane has the ideal composition (formula given above); the compositions ofthese coexisting phases define the two limbs ofa solvus occurring between Ca- and Pb-arsenate apatite end members. The unit-cell parameters and cation–oxygen bond lengths for the arsenate apatites studied are discussed alongside published data for end-member Ca-, Sr-, Ba- and Pbphosphate apatite analogues with (OH), F, Cl or Br as the anions at the centres ofthe channels in the apatite structure. This discussion rationalizes the relationships between the two structural sites A(1) and A(2) occupied by divalent cations in terms ofthe size ofthe A�O polyhedra and the distortion ofthe A(1)�O polyhedron as measured by the metaprism twist angle [O(1)�A(1)�O(2) projected onto (001)]