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The Dynamic Cone Penetrometer (DCP) is a classic and prevalent testing device for evaluating the structural conditions of asphalt pavements in situ. The device consists of a steel rod with a conical tip; the rod guides a small mass that is manually raised and dropped, hammering the tip into the tested pavement. This study was motivated by the idea of utilising the DCP as a seismic source, and subsequently employing geophysical techniques to uncover the shear modulus of deep materials which the tip cannot reach. A seismic survey was carried out over an asphalt road wherein waves caused by a DCP drop were recorded with an array of accelerometers. A forward-interpretation technique was outlined and applied to obtain the shear modulus profile below to road’s surface down to a large depth. The resulting profile was validated by comparison against other measurements. It is concluded that the advocated idea is practical and useful, and that it should be extended to investigate the attenuation characteristics of urban infrastructures.

Many studies have been published on the flight activity of stored grain beetles in temperate regions, but few have focussed on tropical and sub-tropical regions. The spatio-temporal patterns of flight activity of Tribolium castaneum (Herbst) and Rhyzopertha dominica (F.) were quantified in a grain growing district on the Tropic of Capricorn in central Queensland, Australia. Nine traps baited with aggregation pheromone lures were monitored at 2-wk intervals (fortnightly) for 1 year along a 28.4 km linear transect that included sites at bulk grain depots and sites away from stored grain. Beetles of both species were trapped every fortnight during the study. The spatio-temporal patterns of flight activity differed greatly across the two species, as predicted from studies elsewhere. Rhyzopertha dominica was widespread across the landscape, as the mean trap catch of this species was equal in depot and non-depot traps. In contrast, T. castaneum was more frequently trapped in depot traps than non-depot traps during the colder months, but was much more widespread across the landscape during the summer months. Tribolium castaneum also showed a clear mid-summer peak in flight activity, whereas R. dominica flight activity was highly variable throughout the study. In general, our results reveal patterns that are consistent with those found for T. castaneum and R. dominica in southern Queensland. The contrasting spatio-temporal patterns of flight activity of R. dominica and T. castaneum show that species-specific approaches may be needed to manage these pests and that the spatio-temporal dynamics of resistance genes may differ across these species.

The paper details the use of acoustic emission generated by active waveguide subsurface instrumentation to monitor the stability of a rail soil cutting slope failure. Operation of the active waveguide, unitary battery-operated acoustic emission sensor and warning communication system are described. Previous field trials reported by the authors demonstrate that acoustic emission rates generated by active waveguides are proportional to the velocity of slope movement, and can therefore be used to detect changes in rates of movement in response to destabilising and stabilising effects, such as rainfall and remediation, respectively. The paper presents a field trial of the acoustic emission monitoring system at a reactivated rail-cutting slope failure at Players Crescent, Totton, Southampton, UK. The results of the monitoring are compared with both periodic and continuous deformation measurements. The study demonstrated that acoustic emission monitoring can provide continuous information on displacement rates, with high temporal resolution. The ability of the monitoring system to detect slope movements and disseminate warnings by way of text messages is presented. The monitoring approach is shown to provide real-time information that could be used by operators to make decisions on traffic safety.

PURPOSE: UVA radiation (315-400 nm) contributes to skin aging and carcinogenesis. The aim of this review is to consider the mechanisms that underlie UVA-induced cellular damage, how this damage may be prevented or repaired and the signal transduction processes that are elicited in response to it. RESULTS: Exposure to ultraviolet (UV) light is well-established as the causative factor in skin cancer. Until recently, most work on the mechanisms that underlie skin carcinogenesis focused on shorter wavelength UVB radiation (280-315 nm), however in recent years there has been increased interest in the contribution made by UVA. UVA is able to cause a range of damage to cellular biomolecules including lipid peroxidation, oxidized protein and DNA damage, such as 8-oxoguanine and cyclobutane pyrimidine dimers. Such damage is strongly implicated in both cell death and malignant transformation and cells have a number of mechanisms in place to mitigate the effects of UVA exposure, including antioxidants, DNA repair, and stress signalling pathways. CONCLUSIONS: The past decade has seen a surge of interest in the biological effects of UVA exposure as its significance to the process of photo-carcinogenesis has become increasingly evident. However, unpicking the unique complexity of the cellular response to UVA, which is only now becoming apparent, will be a major challenge for the field of photobiology in the 21st century

Fiji leaf gall (FLG) caused by Sugarcane Fiji disease virus (SCFDV) is transmitted by the planthopper Perkinsiella saccharicida. FLG is managed through the identification and exploitation of plant resistance. The glasshouse-based resistance screening produced inconsistent transmission results and the factors responsible for that are not known. A series of glasshouse trials conducted over a 2-year period was compared to identify the factors responsible for the erratic transmission results. SCFDV transmission was greater when the virus was acquired by the vector from a cultivar that was susceptible to the virus than when the virus was acquired from a resistant cultivar. Virus acquisition by the vector was also greater when the vector was exposed to the susceptible cultivars than when exposed to the resistant cultivar. Results suggest that the variation in transmission levels is due to variation in susceptibility of sugarcane cultivars to SCFDV used for virus acquisition by the vector.