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Local meteorology over the Great Barrier Reef (GBR) can significantly influence ocean temperatures, which in turn impacts coral ecosystems. While El Niño–Southern Oscillation (ENSO) provides insight into the expected synoptic states, it lacks details of anticipated sub‐seasonal weather variability at local scales. This study explores the influence of the Madden‐Julian oscillation (MJO) on Australian tropical climate, both independently and in combination with ENSO, focusing on GBR impacts. We find that during El Niño periods, including the summer of 2009/10, faster propagating MJO patterns can disrupt background warm, dry conditions, and potentially provide cooling relief via increased cloud cover and stronger winds. In La Niña periods, such as the summer of 2021/22, the MJO tends to be prevented from passing the Maritime continent, forcing it to remain in a standing pattern in the Indian Ocean. This leads to decreased cloud cover and weaker winds over the GBR, generating warm ocean anomalies. Plain Language Summary Bleaching is likely when tropical corals are exposed to ocean temperatures above a threshold for a prolonged period. In austral summer, tropical weather over the Great Barrier Reef (GBR) can vary from hot and sunny to stormy with rain and strong winds. During El Niño, summer weather over the GBR is typically warm, still, and dry, increasing the likelihood of coral bleaching due to increased exposure to solar radiation and decreased mixing. During La Niña, tropical storms, with cooling effects through increased rainfall and cloud cover, are more typical. The Madden‐Julian oscillation (MJO) is an eastward moving storm pattern near the equator that can also influence the background climate over the GBR. We find that the MJO can significantly influence the weather variability over the GBR, altering the expected states of El Niño and La Niña periods. Key Points Composite maps show how the Madden‐Julian oscillation (MJO) can change meteorological patterns on the Great Barrier Reef Cluster analysis is used to show the types of MJO propagation patterns likely to occur during El Niño and La Niña periods Ocean temperature variability is discussed with El Niño/La Niña phases as the background states and the MJO as a sub‐seasonal modulator

Marine heatwaves (MHWs) have caused devasting ecological and socioeconomic impacts worldwide. Understanding the connection of regional events to large‐scale climatic drivers is key for enhancing predictability and mitigating MHW impacts. Despite the reported connection between MHWs globally and El Niño–Southern Oscillation (ENSO), establishing statistically significant links between different types of ENSO events and MHWs remains challenging due to the limited duration of observational data. Here, we use 10,000 years of simulations from a Linear Inverse Model (LIM) to address this issue. Our findings reveal distinct connections between MHWs and ENSO, with diverging influences from different flavors of El Niño and La Niña events. In addition, under long‐lasting El Niño conditions, the likelihood of MHWs increases by up to 12‐fold in the Indian and Pacific Oceans. This study highlights the global connections between ENSO diversity and variations in MHW events. Plain Language Summary Marine heatwaves (MHWs) are periods of prolonged, extremely warm ocean temperatures that have caused widespread ecological and socioeconomic impacts worldwide. The predictability of these events can be improved if we can find connections between regional events and larger climatic drivers, such as El Niño‐Southern Oscillation (ENSO). Both the positive phase of ENSO, El Niño, and its negative phase, La Niña, have been linked to MHWs in various parts of the world. However, not all El Niño and La Niña events are the same, leading to uncertainty in the relationship between ENSO and MHWs. Due to the limited duration of the observational record, a major issue arises with the lack of examples of different types of El Niño and La Niña events in observations. To overcome this challenge, we utilized 10,000 years of simulated data from a near‐global linear inverse model to generate many more samples of possible global ocean temperature configurations. We find strong differences between regional MHWs and different types of El Niño and La Niña events. In some regions, the probability of MHWs is 12 times more likely under long‐lasting El Niño events. Key Points Robust links between global marine heatwaves and El Niño–Southern Oscillation (ENSO) diversity are established using 10,000 years of samples from a linear inverse model Marine heatwave (MHW) intensity and frequency in the Northeast Pacific increase significantly during Central Pacific El Niño events MHW intensity and frequency are significantly enhanced in Western Australia during Central Pacific La Niña events

As marine heatwaves (MHWs) become more intense and longer lasting due to global warming, understanding the drivers and impacts of these events is crucial for effective marine resource management. This study investigates the influence of El Niño Southern Oscillation (ENSO), the Indian Ocean Dipole (IOD), Southern Annular Mode (SAM), Sub-Tropical Ridge High (STRH), and Madden Julian Oscillation (MJO) on sea surface temperature (SST) anomalies and MHWs around Australia. The aim of this research is to improve our understanding of the drivers of MHWs on sub-seasonal to seasonal (S2S) timescales, which bridges the gap between short-term weather and interannual to long-term climate variability. By analysing SST anomalies and MHWs characteristics during specific driver phases, a simple MHW hazard index is developed. Our findings support previous research indicating that La Niña plays a role in driving MHWs off the coast of Western Australia and reveals a previously unrecognised connection between ocean warming off Queensland and Tasman Sea low-pressure systems associated with the negative phase of the STRH. Our research emphasizes the importance of considering multiple drivers and their compounding effects on MHWs by showing significant changes to typical La Niña MHW patterns with the additional influence of the MJO. By considering drivers acting in the S2S timescale, forecasts can more accurately capture the timing, intensity, and spatial extent of MHW events within a season. These improved forecasts can enhance the ability of marine managers to adapt and allocate resources based on evolving climate conditions, enabling effective implementation of harm minimisation strategies.

Positron emission tomography (PET) imaging of the 18 kDa translocator protein (TSPO), which is upregulated in activated microglia, is a method for investigating whether immune activation is evident in the brain of adults with schizophrenia. This study aimed to measure TSPO availability in the largest patient group to date, and to compare it between patients with recent onset (ROS) and established (ES) schizophrenia. In total, 20 ROS patients (14 male), 21 ES (13 male), and 21 healthy controls completed the study. Patients were predominantly antipsychotic-medicated. Participants underwent a PET scan using the TSPO-specific radioligand [11C](R)-PK11195. The primary outcome was binding potential (BPND) in the anterior cingulate cortex (ACC). Secondary outcomes were BPND in six other regions. Correlations were investigated between TSPO availability and symptom severity. Data showed that mean BPND was higher in older (ES and controls) compared with younger (ROS and controls) individuals, but did not significantly differ between ROS or ES and their respective age-matched controls (ACC; ANOVA main effect of diagnosis: F1,58 = 0.407, p = 0.526). Compared with controls, BPND was lower in antipsychotic-free (n = 6), but not in medicated, ROS patients. BPND in the ES group was negatively correlated with positive symptoms, and positively correlated with negative symptom score. Our data suggest ageing is associated with higher TSPO but a diagnosis of schizophrenia is not. Rather, subnormal TSPO levels in drug-free recent-onset patients may imply impaired microglial development and/or function, which is counteracted by antipsychotic treatment. The development of novel radioligands for specific immune-mechanisms is needed for further clarification.

In this study we performed a genotype-phenotype association analysis of meiotic stability in 10 autotetraploid Arabidopsis lyrata and A. lyrata/A. arenosa hybrid populations collected from the Wachau region and East Austrian Forealps. The aim was to determine the effect of eight meiosis genes under extreme selection upon adaptation to whole genome duplication. Individual plants were genotyped by high-throughput sequencing of the eight meiosis genes (ASY1, ASY3, PDS5b, PRD3, REC8, SMC3, ZYP1a/b) implicated in synaptonemal complex formation and phenotyped by assessing meiotic metaphase I chromosome configurations. Our results reveal that meiotic stability varied greatly (20-100%) between individual tetraploid plants and associated with segregation of a novel ASYNAPSIS3 (ASY3) allele derived from A. lyrata. The ASY3 allele that associates with meiotic stability possesses a putative in-frame tandem duplication (TD) of a serine-rich region upstream of the coiled-coil domain that appears to have arisen at sites of DNA microhomology. The frequency of multivalents observed in plants homozygous for the ASY3 TD haplotype was significantly lower than in plants heterozygous for ASY3 TD/ND (non-duplicated) haplotypes. The chiasma distribution was significantly altered in the stable plants compared to the unstable plants with a shift from proximal and interstitial to predominantly distal locations. The number of HEI10 foci at pachytene that mark class I crossovers was significantly reduced in a plant homozygous for ASY3 TD compared to a plant heterozygous for ASY3 ND/TD. Fifty-eight alleles of the 8 meiosis genes were identified from the 10 populations analysed, demonstrating dynamic population variability at these loci. Widespread chimerism between alleles originating from A. lyrata/A. arenosa and diploid/tetraploids indicates that this group of rapidly evolving genes may provide precise adaptive control over meiotic recombination in the tetraploids, the very process that gave rise to them.

Abstract The variability in the response to antipsychotic medication in schizophrenia may reflect between-patient differences in neurobiology. Recent cross-sectional neuroimaging studies suggest that a poorer therapeutic response is associated with relatively normal striatal dopamine synthesis capacity but elevated anterior cingulate cortex (ACC) glutamate levels. We sought to test whether these measures can differentiate patients with psychosis who are antipsychotic responsive from those who are antipsychotic nonresponsive in a multicenter cross-sectional study. 1H-magnetic resonance spectroscopy (1H-MRS) was used to measure glutamate levels (Glucorr) in the ACC and in the right striatum in 92 patients across 4 sites (48 responders [R] and 44 nonresponders [NR]). In 54 patients at 2 sites (25 R and 29 NR), we additionally acquired 3,4-dihydroxy-6-[18F]fluoro-l-phenylalanine (18F-DOPA) positron emission tomography (PET) to index striatal dopamine function (Kicer, min−1). The mean ACC Glucorr was higher in the NR than the R group after adjustment for age and sex (F1,80 = 4.27; P = .04). This was associated with an area under the curve for the group discrimination of 0.59. There were no group differences in striatal dopamine function or striatal Glucorr. The results provide partial further support for a role of ACC glutamate, but not striatal dopamine synthesis, in determining the nature of the response to antipsychotic medication. The low discriminative accuracy might be improved in groups with greater clinical separation or increased in future studies that focus on the antipsychotic response at an earlier stage of the disorder and integrate other candidate predictive biomarkers. Greater harmonization of multicenter PET and 1H-MRS may also improve sensitivity.

Background Biodegradable (BD) oesophageal stents have been available commercially only since 2008 and previous published research is limited. Our aim was to review the use of BD stents to treat dysphagia in benign or malignant oesophageal strictures. Methods Patients were identified from a prospective interventional radiological database. BD stents were inserted radiologically under fluoroscopic control. Results Between July 2008 and February 2011, 25 attempts at placing SX-ELLA biodegradable oesophageal stents were made in 17 males and five females, with a median age of 69 (range = 54–80) years. Two patients required more than one BD stent. Indications were benign strictures ( n  = 7) and oesophageal cancer ( n  = 17). One attempt was unsuccessful for a technical success rate of 96% with no immediate complications. Clinical success rate was 76%. Median dysphagia score before stent insertion was 3 (range = 2–4) compared to 2 (range = 0–3) after stent insertion ( p  = 0.0001). Conclusion BD stents provide good dysphagia relief for the life time of the stent. They may help avoid the use of feeding tubes in patients having radical chemoradiotherapy or awaiting oesophagectomy. They do not require removal or interfere with radiotherapy planning via imaging. However, the reintervention rate is high after the stent dissolves.

Impaired cognition is associated with lower quality of life and poor outcomes in schizophrenia. Brain glutamate may contribute to both clinical outcomes and cognition, but these relationships are not well-understood. We studied a multicentre cohort of 85 participants with non-affective psychosis using proton magnetic resonance spectroscopy. Glutamate neurometabolites were measured in the anterior cingulate cortex (ACC). Cognition was assessed using the Brief Assessment for Cognition in Schizophrenia (BACS). Patients were categorised as antipsychotic responders or non-responders based on treatment history and current symptom severity. Inverted U-shaped associations between glutamate or Glx (glutamate + glutamine) with BACS subscale and total scores were examined with regression analyses. We then tested for an interaction effect of the antipsychotic response group on the relationship between glutamate and cognition. ACC glutamate and Glx had a positive linear association with verbal memory after adjusting for age, sex and chlorpromazine equivalent dose (glutamate, β = 3.73, 95% CI = 1.26–6.20, P = 0.004; Glx, β = 3.38, 95% CI = 0.84–5.91, P = 0.01). This association did not differ between good and poor antipsychotic response groups. ACC glutamate was also positively associated with total BACS score (β = 3.12, 95% CI = 0.01–6.23, P = 0.046), but this was not significant after controlling for antipsychotic dose. Lower glutamatergic metabolites in the ACC were associated with worse verbal memory, and this relationship was independent of antipsychotic response. Further research on relationships between glutamate and cognition in antipsychotic responsive and non-responsive illness could aid the stratification of patient groups for targeted treatment interventions.

Marine heatwaves (MHWs) can severely impact marine biodiversity, fisheries, and aquaculture. Consequently, there is an increasing desire to understand the drivers of these events to inform their predictability so that proactive decisions may be made to reduce potential impacts. In the Tasman Sea (TS), several relatively intense and broad-scale MHWs have caused significant damage to marine fisheries and aquaculture industries. To assess the potential predictability of these events, we first determined the main driver of each MHW event in the TS from 1993 to 2021. We found that those MHWs driven by ocean advection–approximately 45% of all events–are generally longer in duration and less intense and affected a smaller area compared with the remaining 55%, which are driven by air–sea heat fluxes, are shorter in duration, and are more surface intense. As ocean advection–driven events in the TS have been closely studied and reported previously, we focus here on atmospherically driven MHWs. The predictability of these events is assessed by identifying the patterns of atmospheric pressure, winds, and air–sea heat fluxes in the Southern Hemisphere that coincide with MHWs in the Tasman Sea. We found that atmospherically driven MHWs in this region are more likely to occur during the positive phase of the asymmetric Southern Annular Mode (A-SAM)–which presents as an atmospheric zonal wave-3 pattern and is more likely to occur during La Niña years. These A-SAM events are linked to low wind speeds and increased downward solar radiation in the TS, which lead to increased surface ocean temperatures through the reduction of mixing.