Haemolytic anaemia in cattle in NSW associated with Theileria infections

Several outbreaks of anaemia, jaundice, abortion and mortality in cattle in New South Wales were attributed to the intracellular parasite, Theileria buffeli . Disease occurred predominantly in periparturient animals that had been moved from inland to coastal areas. Diagnosis was made via exclusion of other causes of haemolytic anaemia and observation of the parasite in blood smears. Treatments included both registered and non-registered products. There is a possibility of a new strain of Theileria sp. in Australia and the possible vectors encountered in NSW are discussed.     

Rotation of a single molecule within a supramolecular bearing

Experimental visualization and verification of a single-molecule rotor operating within a supramolecular bearing is reported. Using a scanning tunneling microscope, single molecules were observed to exist in one of two spatially defined states laterally separated by 0.26 nanometers. One was identified as a rotating state and the other as an immobilized state. Calculations of the energy barrier for rotation of these two states show that it is below the thermal energy at room temperature for the rotating state and above it for the immobilized state.     

Design of a surface alloy catalyst for steam reforming

Detailed studies of elementary chemical processes on well-characterized single crystal surfaces have contributed substantially to the understanding of heterogeneous catalysis. Insight into the structure of surface alloys combined with an understanding of the relation between the surface composition and reactivity is shown to lead directly to new ideas for catalyst design. The feasibility of such an approach is illustrated by the synthesis, characterization, and tests of a high-surface area gold-nickel catalyst for steam reforming.     

Soil microbial tests for discriminating between different cropping systems and fertiliser regimes

The aim of this study was to evaluate a set of microbial soil tests for their ability to discriminate between different agricultural practices. For this purpose three sites included in the Swedish Long-Term Soil Fertility Experiments were chosen. The fertility experiments were designed to compare different cropping systems (simulating farming with and without livestock), PK-fertiliser and N-fertiliser regimes. Six different microbial tests were used to derive nine variables describing: (1) basal microbial activity (B-res), (2) potential microbial activities (substrate induced respiration, SIR; potential NH₄ ⁺ oxidation, PAO; potential denitrification activity, PDA; and alkaline phosphatase activity, Alk-P), (3) specific microbial growth rates (μ _res and μ _PDA) and (4) nutrient-limited respiration rates (maximal P-limited respiration, Max-P; and maximal N-limited respiration, Max-N?). Among the individual microbial variables B-res, SIR, μ _res and μ _PDA were the best discriminators of the two different cropping systems. All of them, except μ _PDA, showed some degree of interaction between different treatments. However, the best discriminators between cropping systems were the components [principal component (PC)?1 and 2] from a PC analysis (PCA). In all three soils PC?1 discriminated well between the two cropping systems. In addition, PC?1 and PC?2 reflected the P-fertilisation rate. Max-P alone had the best potential to reflect the microbially available P in the soil and thereby indirectly the plant-available P. The μ _res was also useful when assessing available P in the soil. The N-fertilisation rate seemed to be the most difficult treatment to assess with the microbial activity variables. In addition, PCA revealed a consistent functional relationship in all three soils between the potential activity variables (SIR, PAO, PDA, and Alk-P).     

Development of a Potato Cultivar (<Emphasis Type="Italic">Solanum tuberosum</Emphasis> L.) Core Collection,a Valuable Tool to Prospect Genetic Variation for Novel Traits

This study presents the development of a core collection capturing the genetic diversity of a collection of 350 tetraploid cultivated potato varieties (Solanum tuberosum L.). The core collection was established by using simple sequence repeats (SSR) data and the M strategy, which aims at maximizing the allelic diversity. A 48-core collection was defined which captured 99.5% of the SSR alleles used to establish it, and 96.9% of the SSR alleles which belonged to an independent set of markers. The defined core collection was further validated by analysing 35 agro-morphological traits. The class coverage value and the estimates of the Shannon-Weaver diversity index indicated a good representation of the phenotypic diversity in the core collection. Furthermore, the core set included accessions having the most desirable status for several agronomic traits. A linkage disequilibrium (LD) analysis, using data obtained with the SolCAP SNP array on the defined core collection, was performed. The population structure analysis showed that the core collection did not present a clear genetic structure. The linkage disequilibrium analysis carried out between markers located on the same pseudomolecule within 10,000 bp concluded that 41.3% of these pairs of SNP markers have a significant LD. We conclude that this core collection, representative of the genetic diversity of cultivated potato varieties, is a relevant tool for a first screening for genetic variation regarding novel traits of interest.