IODP-ICDP Workshop examines challenges of fault zone drilling

No abstract available. doi:10.2204/iodp.sd.s01.12.2007</a

Assessment of novel gear designs to reduce interactions between species

This project tested modified gillnets designed by commercial net fishers in the Queensland East Coast Inshore Finfish Fishery (ECIFF) to try and identify gears that would mitigate and/or improve interactions between fishing nets and Species of Conservation Interest (SOCI). The study also documents previously unrecognised initiatives by pro-active commercial net fishers that reflect a conservation-minded approach to their fishing practices, which is the opposite of what is perceived publicly. Between 2011 and 2014, scientists from James Cook University and the Queensland Department of Agriculture and Fisheries teamed with commercial fishers representing the Queensland Seafood Industry Association and the Moreton Bay Seafood Industry Association to conduct field trials of various modified net designs under normal fishery conditions. Trials were conducted in Moreton Bay (southern part of the fishery) and Bowling Green Bay (northern) and tested different net designs developed by fishers to improve the nature of interactions between net fishing gear and SOCI

Planning for an uncertain future in progressive neurological disease: a qualitative study of patient and family decision-making with a focus on eating and drinking

Abstract Background Dysphagia and other eating and drinking difficulties are common in progressive neurological diseases. Mealtimes can become a major source of difficulty and anxiety for patients and their families. Decisions about eating, drinking and care can become challenging as disease progresses, and the person in question loses the capacity to participate in decisions about their own care. We sought to investigate how patients and their family members make decisions about their future care as their condition deteriorates, with a particular focus on mealtimes, eating and drinking. Methods Longitudinal qualitative in-depth interviews were undertaken with patients and their family members (N = 29) across a range of disease groups, including: dementia, Parkinson’s Disease, Huntington’s Disease, Progressive Supranuclear Palsy, Motor Neurone Disease, Multiple Sclerosis. Patients had varying degrees of eating and drinking difficulties, and levels of decision-making capacity. Interviews were ‘participant led’ and undertaken in the patients’ own homes or a place of their choosing. Follow-up interviews were three months to one year later depending upon disease trajectory. Interviews were audio recorded and analysed in NVivo using a Thematic Analysis approach. Results Twenty-nine participants were interviewed between 2015 and 2017. Two key themes emerged from the analysis: 1) Health Literacy: the extent to which patients and relatives appeared to know about the condition and its treatment. Patients and their family members varied in their ability to speak and communicate about their condition and prognosis. 2) Planning style: the extent to which participants appeared to value involvement in advance care-planning. Patients and their family members varied in the way in which they made decisions: some preferred to ‘take each day as it comes’, while others wished to plan extensively for the future. Conclusions Issues with eating and drinking are often overlooked. Clinicians need to understand both the patient’s level of health literacy and their style of planning before communicating with patients and their families about these sensitive issues

Measuring spent fuel assembly multiplication in borated water with a passive neutron albedo reactivity instrument

Abstract The performance of a passive neutron albedo reactivity (PNAR) instrument to measure neutron multiplication of spent nuclear fuel in borated water is investigated as part of an integrated non-destructive assay safeguards system. To measure the PNAR Ratio, which is proportional to the neutron multiplication, the total neutron count rate is measured in high- and low-multiplying environments by the PNAR instrument. The integrated system also contains a load cell and a passive gamma emission tomograph, and as such meets all the recommendations of the IAEA’s recent ASTOR Experts Group report. A virtual spent fuel library for VVER-440 fuel was used in conjunction with MCNP simulations of the PNAR instrument to estimate the measurement uncertainties from (1) variation in the water boron content, (2) assembly positioning in the detector and (3) counting statistics. The estimated aggregate measurement uncertainty on the PNAR Ratio measurement is 0.008, to put this uncertainty in context, the difference in the PNAR Ratio between a fully irradiated assembly and this same assembly when fissile isotopes only absorb neutrons, but do not emit neutrons, is 0.106, a 13-sigma effect. The 1-sigma variation of 0.008 in the PNAR Ratio is estimated to correspond to a 3.2 GWd/tU change in assembly burnup.Peer reviewe

3D Target Detection and Spectral Classification for Single-photon LiDAR Data

3D single-photon LiDAR imaging has an important role in many applications. However, full deployment of this modality will require the analysis of low signal to noise ratio target returns and a very high volume of data. This is particularly evident when imaging through obscurants or in high ambient background light conditions. This paper proposes a multiscale approach for 3D surface detection from the photon timing histogram to permit a significant reduction in data volume. The resulting surfaces are background-free and can be used to infer depth and reflectivity information about the target. We demonstrate this by proposing a hierarchical Bayesian model for 3D reconstruction and spectral classification of multispectral single-photon LiDAR data. The reconstruction method promotes spatial correlation between point-cloud estimates and uses a coordinate gradient descent algorithm for parameter estimation. Results on simulated and real data show the benefits of the proposed target detection and reconstruction approaches when compared to state-of-the-art processing algorithm