Pathogen carriage by the cat flea Ctenocephalides felis (Bouché) in the United Kingdom

The carriage of Bartonella, Rickettsia felis and haemoplasma species was investigated in cat fleas (Ctenocephalides felis) collected from 121 cats and dogs in the United Kingdom. DNA extracted from fleas was analysed using genus and species-specific PCR and amplicons were characterised using DNA sequencing. Fifty percent of flea samples were PCR positive for at least one pathogen. Twenty one percent were positive for R. felis, 17% for Bartonella henselae, 40% for haemoplasma species and 20% were infected with more than one of the pathogen species studied. It is clear from the results in this study that companion cats and dogs are commonly infested with Ct. felis carrying bacterial pathogens of significance to human and animal health. These findings raise the possibility that Ct. felis found on dogs and cats are a potential source of infection with such pathogens for humans.     

Pasture and forage crop systems for non-irrigated dairy farms in southern Australia. 2. Inter-annual variation in forage supply,and business risk

Inter-annual climatic variability poses a substantial management and profitability challenge for pasture-based dairy producers in southern Australia. The effects of a range of seasonal scenarios on the production and profit of non-irrigated dairy farm systems using several different forage bases were investigated for two regions in southeast Australia using a systems modeling approach. For the Terang district, seasonal scenarios were constructed around combinations of early, average or late autumn rains, and short, average or long spring flushes. For the higher-rainfall Ellinbank district, scenarios were constructed around either above- or below-average summer–autumns or winter–springs.     

Measuring tensile strength of nanofibers using conductive substrates and dynamic mechanical analyzer

Though the tensile strength of nanofibers is essential to determine their application fields, few studies have been conducted on this topic, due to the difficulties involved in the preparation of single nanofiber tensile specimens, the manipulation of the clamping device, and the sensing of the nano- force and strain. A bundle testing method was employed in this work to measure the tensile strength of nanofibers. For this purpose, a conductive substrate was designed to hold several thousand nanofibers extruded from a spinning nozzle and align them uniaxially during the electrospinning process. This substrate was designed for a dynamic mechanical analyzer (DMA), because most DMAs are equipped with fine sensors sensitive enough to measure a very small force and strain. Nylon 6 nanofibers were electrospun and collected on the substrate. Then, they were elongated simultaneously in the DMA until they were fractured, showing that the aligned nanofibers have superior tensile strength and modulus compared to their counterpart microfibers and thus suggesting that polymeric nanofibers have the potential to be used as reinforcement fibers for composite materials.