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To date, 18 living recommendations for the clinical care of pregnant and postpartum women with COVID-19 have been issued by the National COVID-19 Clinical Evidence Taskforce. This includes recommendations on mode of birth, delayed umbilical cord clamping, skin-to-skin contact, breastfeeding, rooming-in, antenatal corticosteroids, angiotensin-converting enzyme inhibitors, disease-modifying treatments (including dexamethasone, remdesivir and hydroxychloroquine), venous thromboembolism prophylaxis and advanced respiratory support interventions (prone positioning and extracorporeal membrane oxygenation). Through continuous evidence surveillance, these living recommendations are updated in near real-time to ensure clinicians in Australia have reliable, evidence-based guidelines for clinical decision-making. Please visit https://covid19evidence.net.au/ for the latest recommendation updates.

This paper investigates if the relationship between the global and local moduli of elasticity (MoE), measured in bending tests, is affected by the test machines employed, and how that may influence strength grading. The ultimate aim is to study the potential influence of those factors on the yields of graded timber in Europe, and improve the standards used. More than 2000 structural timber pieces of Douglas fir (Pseudotsuga menziesii), larch (Larix spp.) and spruce (Picea sitchensis & P. abies) grown in Ireland and the United Kingdom, were tested using two different test machines. The results are examined, and compared to the dynamic MoE measured using longitudinal vibration resonance. Results found that there can be a sufficiently large systematic effect of the test machine on the measurement of MoE, to potentially be transferred to the grading process with important consequences in the yields of structural grade timber. Furthermore, adjustment factors for MoE, as used in the standards, may not be transferable between laboratories, even when the species and timber source are the same. Caution is therefore recommended when deriving or using these MoE adjustment equations, with due care to ensuring the timber is of similar characteristics and tested under as similar as possible setups. The extrapolation of models derived from other sources is best avoided, unless confirmed by cross-checking measurements. This work was developed within the WoodProps programme funded by the Forest Sector Development Division of the Department of Agriculture, Food and the Marine, Ireland. The authors are also grateful to the various funders and collaborators of the original research that produced the test data. Particular thanks are extended to Coillte and Murray Timber Group Ltd for the material supplied in Ireland, and Tom Drewett, Gregory Searles, Karlo Simic and Luka Krajnc for the use of data from their PhD studies. non-peer-reviewed

The paper presents the results of non-destructive longitudinal resonance (impulse excitation technique), and mechanical flexural testing, of a batch of European beech wood (Fagus sylvatica L.), grown in the United Kingdom. The material was largely free from visible defects and straight grained, having been visually appearance graded by the sawmill. The dynamic modulus of elasticity of original length boards is compared to density and global modulus of elasticity results from short lengths cut from a subset of those boards, tested in four-point bending about the minor axis. A method of weighting, based on the first mode wavelength, is shown to improve the correlation, partly accounting for variation within the boards, and the relative contribution to the resonance behaviour. The results are used to estimate the structural grading of the full batch and shown to be similar to results from previous small clear testing of UK-grown beech (within 5-10%). The relatively small number of boards from a single batch, from a single location means that the results are only an indication of potential quality, but they give confidence that further research should be done into the potential of UK-grown beech, especially for glued-laminated construction products, as has been done in Europe.

The paper presents a study of the tension properties of Irish-grown Sitka spruce. Fifty timber pieces were destructively tested having resonant frequency and knots measured. The aim was to improve knowledge of the performance of spruce in tension and to check the suitability of the equations given in the European standards to calculate secondary properties from grade determining properties. Static stiffness, whichlimited the grading of the dataset, was largely predicted using dynamic modulus of elasticity (MoEdyn). Tension strength was modelled using density and tKAR index. It was found also that adding MoEdyn in a linear regression was not useful. The research reveals that the equation given in EN384:2018 for tension strength, based on populations of higher stiffness than Irish spruce, results in values that may not be appropriate for Irish-grown spruce timber. ECC Timber Products for the donation of material used in this study, and Luka Krajnc for the use of material from his PhD thesis. non-peer-reviewed