Regional agricultural governance in peri-urban and rural South Australia: strategies to improve multifunctionality

Historically, agricultural policy in Australia has focused on maximising the economic productivity and efficiency of the sector. The issues that have arisen from this governance focus are manyfold. In this study, we illustrate the regional disparity and implications for agricultural sustainability caused by such a policy model. We surveyed farmers in two South Australian case study regions, the adjoining peri-urban Barossa-Light region, and the rural area of Loxton. It was found that respondents from Loxton had larger properties, saw more benefits from government support for agriculture, and were more likely to prioritise support for their local community and increases in productivity. Respondents from Barossa-Light were more concerned about risks of urban encroachment, prioritised keeping their farms in their families, and were generally more concerned about government support. These results highlight the complexity involved with applying appropriate government support mechanisms across a diverse industry such as agriculture, with various regional sustainability issues driving respondent priorities. We also suggest that regional variation will require explicit planning which aims for heterogeneous goals and that educational and cooperative pursuits may help to increase the capacity of the land managers in the case study regions. These suggestions have broader implications for other regions where agricultural diversity complicates policy to support the industry within historically productivist agricultural regimes.Simon J. Fielke, Douglas K. Bardsle

Resonant contributions to single charge transfer between He++ and He

Energy levels and lifetimes are calculated for the resonant states that are important in radiative single charge transfer in He2+-He collisions at thermal energies. The resonant contribution to the charge-transfer rate decreases with increasing temperature and is approximately 12% of the total rate at 300 K

Mobility of α particles in helium

The mobility of α particles in helium gas is calculated using the zeroth-order Viehland-Mason theory with interaction potentials recently computed by Cohen and Bardsley. The results show a dependence on field strength similar to the measurements of Johnsen and Biondi but are lower in magnitude by about 5%

Exposing errors related to weak memory in GPU applications

© 2016 ACM.We present the systematic design of a testing environment that uses stressing and fuzzing to reveal errors in GPU applications that arise due to weak memory effects. We evaluate our approach on seven GPUS spanning three NVIDIA architectures, across ten CUDA applications that use fine-grained concurrency. Our results show that applications that rarely or never exhibit errors related to weak memory when executed natively can readily exhibit these errors when executed in our testing environment. Our testing environment also provides a means to help identify the root causes of such errors, and automatically suggests how to insert fences that harden an application against weak memory bugs. To understand the cost of GPU fences, we benchmark applications with fences provided by the hardening strategy as well as a more conservative, sound fencing strategy

Specification and verification of atomic operations in GPGPU programs

We propose a specification and verification technique based on separation logic to reason about data race freedom and functional correctness of GPU kernels that use atomic operations as synchronisation mechanism. Our approach exploits the notion of resource invariant from Concurrent Separation Logic (CSL) to capture the behaviour of atomic operations. However, because of the different memory levels in the GPU architecture, we adapt this notion of resource invariant to these memory levels, i.e., group resource invariants capture the behaviour of atomic operations that access locations in local memory, while kernel resource invariants capture the behaviour of atomic operations that access locations in global memory. We show soundness of our approach and we provide tool support that enables us to verify kernels from standard benchmarks suites

Dissociative attachment in HCl, DCl, and F2

Resonant scattering models, using nonlocal decay widths, are developed for dissociative attachment of slow electrons to diatomic molecules. Cross sections are obtained for HCl and DCl in several initial rotational and vibrational states, and the dependence of the average attachment cross section upon the rotational and vibrational temperature is examined. For F_2 the cross section for ground state molecules agrees well with experiment above 0.2 eV but shows no zero energy peak. The attachment cross section is higher for vibrationally excited molecules, but the enhancement is much less than that found in H_2 and HCl

The potential of decision support systems to improve risk assessment for pollen beetle management in winter oilseed rape

BACKGROUNDThe reliance on and extensive use of pyrethroid insecticides have led to pyrethroid resistance in pollen beetle (Meligethes aeneus). Widespread adoption of best practice in pollen beetle management is therefore needed. Decision support systems (DSSs) that identify the risk period(s) for pest migration can help to target monitoring and control efforts, but they must be accurate and labour efficient to gain the support of growers. Weather data and the phenology of pollen beetles in 44 winter oilseed rape crops across England over 4 years were used to compare the performance of two risk management tools: the DSS proPlant expert, which predicts migration risk according to a phenological model and local weather data, and rule-based advice', which depends on crop growth stage and a temperature threshold. RESULTSBoth risk management tools were effective in prompting monitoring that would detect breaches of various control thresholds. However, the DSS more accurately predicted migration start and advised significantly fewer days of migration risk, consultation days and monitoring than did rule-based advice. CONCLUSIONThe proPlant expert DSS reliably models pollen beetle phenology. Use of such a DSS can focus monitoring effort to when it is most needed, facilitate the practical use of thresholds and help to prevent unnecessary insecticide applications and the development of insecticide resistance. (c) 2015 Rothamsted Research Ltd. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry

An Unidentified Filarial Species and its Impact on Fitness in Wild Populations of the Black-Footed Ferret (\u3ci\u3eMustela nigripes\u3c/i\u3e)

Disease can threaten the restoration of endangered species directly by substantially decreasing host survival or indirectly via incremental decreases in survival and reproduction. During a biomedical survey of reintroduced populations of the highly endangered black-footed ferret from 2002 to 2005, microfilariae discovered in the blood were putatively identified as Dirofilaria immitis, and widespread screening was initiated using a commercially available antigen-based ELISA test. A subset of animals (n = 16) was screened for D. immitis using a highly sensitive PCR-based assay. Microfilariae were also molecularly and morphologically characterized. Of 198 animals at six reintroduction sites, 12% had positive results using the ELISA test. No antigen-positive animals which were screened via PCR (n = 11) had positive PCR results, and all antigen-positive animals (n=24) were asymptomatic. No significant differences were found in body mass of antigen-positive (male: 1223±82 g [mean±SD], female: 726±75 g) vs. antigen-negative (male: 1,198±119 g, female: 710±53 g) individuals (P=0.4). Antigen prevalence was lower in juveniles (3%) than adults (12%; P=0.03), and higher in in situ, captive-reared individuals (33%) than wild-born individuals (10%; P=0.005). Morphologic, analysis of microfilariae revealed they were neither D. immitis nor any other previously characterized North American species. PCR amplification of the 5S spacer region of rDNA revealed that the filarial sequence shared only 76% identity with D. immitis. This previously unidentified filarial sequence was present in all antigen positive animals (11 of 11 tested). It appears that black-footed ferrets were infected with a previously undescribed species of filaria whose antigen cross-reacted with the ELISA assay, although further analysis is needed to make a conclusive statement. Nonetheless, this previously undescribed filaria does not appear to threaten recovery for this highly endangered mammal