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Settlement and tidal zonation patterns of closely related oysters within the genus <i>Saccostrea</i> in a subtropical Australian estuary --implications for restoration
No full textOyster reefs are considered functionally extinct in many global regions, and restoration efforts are accelerating. Currently, restoration on Australia's eastern coast is focused on the Sydney rock oyster (Saccostrea glomerata); however, multiple species of Saccostrea are found across this region. To understand the intertidal zonation patterns of co-occurring Saccostrea species, we surveyed wild assemblages of adult oysters at different intertidal elevations in the subtropical Noosa River estuary using molecular methods for species identification. We then conducted an oyster gardening experiment across three tidal elevations to assess spat recruitment patterns and determine whether oyster gardening is a viable method of seeding shell for restoration. Adult S. glomerata were more abundant in the upper intertidal zone, whereas adults of the related (but as yet unnamed) Saccostrea lineage G were found almost exclusively in the lower intertidal zone. Spat recruitment was highest in the intertidal zone and lowest in the subtidal zone, indicating that subtidal restoration targeting Saccostrea species may be unsuccessful in this region. We concluded that lineage G is likely to be reef-building; however, restoration programs will likely rely on in situ recruitment for this species until knowledge relating to spawning triggers can inform reliable hatchery production. Furthermore, we show that oyster gardening can be a viable method of seeding shell when systems are not recruitment limited. This method will likely be useful for multispecies restoration across the tropics, where there are many co-occurring and often morphologically indistinguishable reef-building species, providing benefits that far outweigh those of single-species approaches
Oscillations across time and space:archeoacoustics and the sonic imagination of Hannan Jones’ A Frontier in Depth (2025) (in English and Welsh)
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Alternative expression of message passing on networks
No full textMessage passing techniques on networks encompasses a family of related methods that can be employed to ascertain many important properties of a network. It is widely considered to be the state of the art formulation for networked systems and advances in this method have a wide impact across multiple literatures. One property that message passing can yield is the size of the largest connected component in the network following bond percolation. In this paper, we introduce an alternative method of finding this value that differs from the standard approach. Like the canonical approach, our method is exact on trees and an approximation on arbitrary graphs. We show that our method lends itself to the description of a variety of generalisations of bond percolation such as sequential percolation and non-binary percolation and can yield information about the local environment of a node in percolation equilibrium that the traditional approach cannot
Hyperphosphorescent OLEDs:harnessing the power of MR-TADF terminal emitters
No full textHyperphosphorescent organic light-emitting diodes (HP-OLEDs) represent an attractive solution to persistent efficiency roll-off and device stability issues, combining phosphorescent sensitizers with fluorescent terminal emitters to achieve efficient, narrowband emission. This review discusses advances in HP-OLEDs where the terminal emitter is a multiresonance thermally activated delayed fluorescence compound. Recent breakthroughs in device performance, including examples demonstrating both high maximum external quantum efficiencies (EQEmax) and excellent color purity, are highlighted. This review summarizes design strategies, challenges, and future directions for improving the efficiency, stability, and spectral performance of HP-OLEDs
Observable-enriched entanglement
No full textWe introduce methods of characterizing entanglement on the example of the quantum skyrmion Hall effect, in which entanglement measures are enriched by the matrix representations of operators for observables. These observable operator matrix representations can enrich the partial trace over subsets of a system's degrees of freedom, yielding reduced density matrices useful in computing various measures of entanglement, which also preserve the observable expectation value. We focus here on applying these methods to compute observable-enriched entanglement spectra, unveiling bulk-boundary correspondences of canonical four-band models for topological skyrmion phases and their connection to simpler forms of bulk-boundary correspondence. Given the fundamental roles entanglement signatures and observables play in the study of quantum systems and the fundamental generalization of the interpretation and treatment of spin within the framework of the quantum skyrmion Hall effect, concepts of observable-enriched entanglement introduced here are broadly applicable to myriad problems of quantum systems
A very readily prepared ligand for rhodium catalysed propene hydroformylation
No full textIn the search for an easy-to-make ligand that would enable Rh catalyzed hydroformylation of propene to favor the branched aldehydes, iso-butanal, bis-phosphonites and bis-phosphoramidites were designed. Catalysts derived from bis-phosphonites gave the desired low n:iso ratios, but were unstable to hydrolysis. A bis-phosphoramidite ligand (EasyDiPhos) that can be made in just one synthetic step has been discovered that enables Rh-catalyzed hydroformylations to proceed with unusually low n:iso ratios. They were also found to have significant stability to moisture, air, and to relatively high temperatures during hydroformylation conditions. The latter was studied using a combination of high pressure infra-red (HPIR) spectroscopy and NMR analysis of the catalyst resting state after 1 week under relevant conditions. Propene hydroformylation with n:iso ratios well below 1 was carried out and with turnover numbers around 1000 mol/mol in 1 hour reaction time. One of the ligands, whilst not being the most iso-selective example, had a partially flexible n:iso ratio depending on temperature and pressure. Two Pt(II) complexes were prepared and their X-ray crystal structures determined. The most iso-selective catalyst was examined at low temperature (prioritizing iso-selectivity over rates) in hydroformylation of some other terminal alkenes with significant branched selectivity
Enhanced diagnosis of thyroid diseases through advanced machine learning methodologies
No full textThyroid disease is a health concern related to the thyroid gland, which is vital for controlling the metabolism of the human body. Predominantly affecting women in their fourth or fifth decades of life, thyroid disease can result in physical and mental issues. This research focuses on improving the diagnostic process by creating a classification model that utilises various machine learning models and a deeplearning model to categorise three types of thyroid disease conditions. This research developed an automated system capable of classifying three thyroid conditions using five machine learning models and a deep learning model. Resampling techniques, such as SMOTE oversampling and Random undersampling, are utilised to correct the issue of class imbalance in the dataset. Finally, a web-based application is developed utilising the most effective model, GBC, which facilitates easy classification of thyroid diseases. The experimental analysis showed that the Gradient Boosting Classifier (GBC), using oversampling techniques, achieved the highest level of performance in classifying thyroid diseases, obtaining an accuracy and F1-Score of 99.76%. This study demonstrated that TSH was the most indicative biomarker for thyroid disease classification. The experimental results proved that the Gradient Boosting Classifier (GBC) utilising the oversampling technique achieved a superior performance compared to other classifier models, with an accuracy and F1-Score of 99.76%. This research presented insights that can assist healthcare practitioners in promptly diagnosing thyroid diseases
