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Background: Larval connectivity between distinct benthic populations is essential for their persistence. Although connectivity is difficult to measure in situ, it can be predicted via models that simulate biophysical interactions between larval behaviour and ocean currents. The blue mussel (Mytilus Edulis L.) is widespread throughout the northern hemisphere and extensively commercialised worldwide. In the Irish Sea, this industry represents ~ 50% of Welsh shellfisheries, where cultivation is mainly based on wild spat. However, the main sources and amount of spat varied interannually (1100 tonnes harvest in 2014 against zero in 2018). The aim of this study is to characterise the structure and dynamics of the blue mussel metapopulation within the northern part of the Irish Sea., Methods: We develop a Lagrangian particle tracking model, driven by a high-resolution (from 30 to 5000 m) validated unstructured coastal hydrodynamic model of the Irish Sea, to simulate spatial and temporal variability of larval dispersal and connectivity between distinct mussel populations and potential settlement areas., Results: Our results showed that: (1) larvae positioned near the surface were strongly influenced by wind-driven currents suggesting that connectivity networks had the potential to span hundreds of kilometres; (2) in contrast, larvae positioned deeper in the water column were driven by tidal currents, producing intricate spatial patterns of connectivity between mussel beds over tens of kilometres that were consistent over time., Conclusions: Dispersal of mussel larvae in the tidally energetic Irish Sea during the April-May spawning season is potentially driven by wind-driven surface currents, as confirmed by fisherman observations of inter-annual variability in wild spat collection. These results have important implications for metapopulation dynamics within the context of climate change and sustainable shellfisheries management (i.e. gain and loss of populations and harvest areas according to wind conditions)., (© 2022. The Author(s).)

Background: Some degree of cognitive decline after surgery occurs in as many as one quarter of elderly surgical patients, and this decline is associated with increased morbidity and mortality. Cognition may be affected across a range of domains, including memory, psychomotor skills, and executive function. Whilst the exact mechanisms of cognitive change after surgery are not precisely known, oxidative stress and subsequent neuroinflammation have been implicated. N-acetylcysteine (NAC) acts via multiple interrelated mechanisms to influence oxidative homeostasis, neuronal transmission, and inflammation. NAC has been shown to reduce oxidative stress and inflammation in both human and animal models. There is clinical evidence to suggest that NAC may be beneficial in preventing the cognitive decline associated with both acute physiological insults and dementia-related disorders. To date, no trials have examined perioperative NAC as a potential moderator of postoperative cognitive changes in the noncardiac surgery setting., Methods and Design: This is a single-centre, randomised, double-blind, placebo-controlled clinical trial, with a between-group, repeated-measures, longitudinal design. The study will recruit 370 noncardiac surgical patients at the University Hospital Geelong, aged 60 years or older. Participants are randomly assigned to receive either NAC or placebo (1:1 ratio), and groups are stratified by age and surgery type. Participants undergo a series of neuropsychological tests prior to surgery, 7 days, 3 months, and 12 months post surgery. It is hypothesised that the perioperative administration of NAC will reduce the degree of postoperative cognitive changes at early and long-term follow-up, as measured by changes on individual measures of the neurocognitive battery, when compared with placebo. Serum samples are taken on the day of surgery and on day 2 post surgery to quantitate any changes in levels of biomarkers of inflammation and oxidative stress., Discussion: The PANACEA trial aims to examine the potential efficacy of perioperative NAC to reduce the severity of postoperative cognitive dysfunction in an elderly, noncardiac surgery population. This is an entirely novel approach to the prevention of postoperative cognitive dysfunction and will have high impact and translatable outcomes if NAC is found to be beneficial., Trial Registration: The PANACEA trial has been registered with the Therapeutic Goods Administration, and the Australian New Zealand Clinical Trials Registry: ACTRN12614000411640 ; registered on 15 April 2014.

Background: The lycophyte Selaginella moellendorffii is a vascular plant that diverged from the fern/seed plant lineage at least 400 million years ago. Although genomic information for S. moellendorffii is starting to be produced, little is known about basic aspects of its molecular biology. In order to provide the first glimpse to the epigenetic landscape of this early divergent vascular plant, we used the methylation filtration technique. Methylation filtration genomic libraries select unmethylated DNA clones due to the presence of the methylation-dependent restriction endonuclease McrBC in the bacterial host., Results: We conducted a characterization of the DNA methylation patterns of the S. moellendorffii genome by sequencing a set of S. moellendorffii shotgun genomic clones, along with a set of methylation filtered clones. Chloroplast DNA, which is typically unmethylated, was enriched in the filtered library relative to the shotgun library, showing that there is DNA methylation in the extremely small S. moellendorffii genome. The filtered library also showed enrichment in expressed and gene-like sequences, while the highest-copy repeats were largely under-represented in this library. These results show that genes and repeats are differentially methylated in the S. moellendorffii genome, as occurs in other plants studied., Conclusion: Our results shed light on the genome methylation pattern in a member of a relatively unexplored plant lineage. The DNA methylation data reported here will help understanding the involvement of this epigenetic mark in fundamental biological processes, as well as the evolutionary aspects of epigenetics in land plants.