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A new species of velvet gecko (Diplodactylidae: Oedura) from basalt habitat of inland north Queensland, Australia
No full textMany Oedura geckos are saxicoline, and a number of these species are restricted to outcropping of a particular rock type. Most commonly this is sandstone, but some species primarily occur on other rock types, such as granite or limestone. There are few areas of extensive basalt outcropping in Australia, and these are typically of young age. Here I describe a new species of Oedura discovered in the Sturgeon Basalt outcropping of inland north-east Queensland, an extensive outcropping of deep age. Oedura atra sp. nov. is readily distinguished from congeners by its relatively dark colouration, with pattern restricted to narrow, pale bands, and other morphological features such as a short, broad tail, and a relatively wide head. It is genetically divergent from, but allied to, several Oedura species in inland north Queensland, with the ND4 mtDNA phylogeny suggesting closest relationship to O. argentea Hoskin, Zozaya & Vanderduys, 2018. Oedura atra sp. nov. appears to be restricted to basalt rocks and is only known from a localised area. However, it is likely to be more widely distributed along the extensive basalt outcropping in this region. Oedura atra sp. nov. best fits a conservation status of Data Deficient, pending further surveys and assessment of potential threats
Public support for novel interventions to protect, restore, and accelerate adaptation to climate change in the Great Barrier Reef
No full textNovel technological interventions are under development to build the resilience of ecosystems by providing short-term protection from climate extremes, enhancing recovery from disturbance, and accelerating adaptation to changed climate states. Drawing on surveys of Australian residents (n = 5320) conducted in 2018 and 2022, this paper investigates support for the development and deployment of six novel interventions on the Great Barrier Reef (marine cloud brightening, fogging, rubble stabilization, coral seeding, natural breeding for heat tolerance, and genetic engineering) and how support varies across time, social groups, perception of climate risk, and approach to intervention. It finds strong support for research and small-scale trials of all six interventions although support was highest for coral seeding, followed by rubble stabilization, fogging, natural breeding, marine cloud brightening, and genetic engineering. Reflecting their early stage of development, support for large-scale deployment of novel interventions across the Great Barrier Reef moderated, with respondents indicating strongest support for deployment of coral seeding, rubble stabilization, and fogging and lower support for natural breeding, marine cloud brightening, and genetic engineering. Trust in science to deliver solutions was a consistently strong predictor of support for both intervention R&D and large-scale deployment. The perceived ability to identify and test environmental impacts was a strong predictor of support for scaled deployment. Perceived climate threat, trust in the Reef's management authority, and ethics were also consistently associated with support for intervention R&D and implementation. With the vast majority of Australian residents supporting strong action to protect and restore coral reefs the maintenance of trust in scientists and scientific institutions stands out as critical to support for the implementation of novel interventions at scale, including the ability of researchers to identify and assess the environmental risks of these interventions
Heterochrony and Oophagy Underlie the Evolution of Giant Filter-Feeding Lamniform Sharks
No full textEvolutionary transitions toward gigantic body sizes have profound consequences for the structure and dynamics of ecological networks. Among elasmobranchs (sharks and rays), gigantism has evolved on several occasions, most notably in the iconic Megalodon (Otodus megalodon†) and the extant whale shark (Rhincodon typus), basking shark (Cetorhinus maximus), and megamouth shark (Megachasma pelagios), all of which reach total lengths exceeding 6 m and, in some cases, reach 21 m or more. Comparative phylogenetic studies suggest that filter feeding and heterothermy provide two alternative evolutionary pathways leading to gigantism in sharks. These selection-based explanations for gigantism are important; however, our understanding of evolutionary transitions in body size is fundamentally constrained without a proximate, mechanistic understanding of how the suite of adaptations necessary to facilitate gigantism evolved. Here we propose the heterochrony hypothesis for the evolution of the giant filter-feeding shark ecomorphotype. We suggest that craniofacial adaptations for oophagy in embryonic stages of lamniform sharks are retained through ontogeny in C. maximus and M. pelagios by paedomorphosis, resulting in an enlarged head and mouth relative to the rest of the body, even in adulthood. This change in developmental timing enables these taxa to optimize prey acquisition, which is thought to be the limiting factor for the evolution of gigantism in filter-feeding marine vertebrates. We discuss the concordance of this hypothesis with current developmental, morphological, and evolutionary data, and we suggest future means by which the hypothesis could be tested
Integrating interspecific traits into biophysical models of seagrass dispersal
No full textThe resilience of seagrass meadows strongly depends on the dispersal of their propagules, which fosters recovery and replenishment after disturbances. However, predicting dispersal patterns across dynamic coastal environments and large spatial and temporal scales remains challenging due to the lack of empirical observations. Biophysical models, integrating oceanic and atmospheric drivers with species-specific traits such as buoyancy and lifespan, are commonly used to simulate propagule transport. Yet, few studies account for the interspecific and interannual variability inherent in tropical seagrass ecosystems. Here we present a high-resolution seagrass biophysical dispersal model applied to 11 tropical seagrass species across the entire Great Barrier Reef World Heritage Area (GBRWHA), Australia, and run this model over a 6-year period (2011–2016). We use this model to assess how the interspecific variability in the buoyancy and windage of seagrass propagules affect their dispersal patterns and how these patterns further vary both seasonally and interannually. Our results reveal that species-specific factors such as their windage and buoyancy, as well as the season and region in which they disperse had the largest influence on dispersal distance. H. spinulosa and S. isoetifolium showed the greatest dispersal in the Whitsunday region, while the wet season promoted higher local retention due to lower wind speeds. From a management perspective, this highlights the need to account for species-specific information when devising seagrass management strategies. The outcomes of this research reveal the inherent complexities of predicting multi-species dispersal over large spatial and temporal scales, with broader implications for predicting dispersal in complex coastal ecosystems
Synthesis and Structures of Oxide -Centred Alkali Metal (K, Li)/Lanthanoid (Ln3 or 4) 3,5-Dimethylpyrazolate Cages - Herbert Schumann Revisited
No full textReaction of lanthanoid tris(3,5-dimethylpyrazolate) compounds, [Ln(Me2pz)3(thf)]2 (Ln=La 1 a, Ce, Pr, Dy 1 b, Yb, Lu) with potassium or lithium bistrimethylsilylamide and with or without added 3,5-dimethylpyrazole, or of lanthanoid tris(bistrimethylsilyl)amide complexes with potassium bistrimethylsilylamide and 3,5-dimethylpyrazole have yielded a variety of oxide centred Ln3 or Ln4/(K or Li)1–3 multinuclear cages, namely, [La4O(Me2pz)11 K(thf)2] (2 a), [La4O(Me2pz)11Li(Me2pzH)]⋅0.5Hexane (2 b), [La4O(Me2pz)10(Me2pzH)] (2 c) (from heating 1 a in toluene), [Ce3O(Me2pz)9K2(dme)2] (3 a), [Ce3O(Me2pz)9Li2(thf)2]⋅0.5Hexane (3 b) and [Ce(Me2pz)5Li2(thf)3] (3 c), which crystallized together, [Ce3O(Me2pz)10K3(thf)3] (3 d), [Pr3O(Me2pz)10K3(thf)3] (4), [Dy3O(Me2pz)9K2(thf)2]⋅THF (5), [Yb3O(Me2pz)9K2(thf)2]⋅THF (6), and [Lu3O(Me2pz)9K2(thf)2]⋅THF (7). Crystals of {[K8(Me2pz)8(thf)2]⋅THF}∞ (8) were also obtained from the preparation of 7. From reaction of [Ce(Me2pz)3(thf)]2 with potassium tert-butoxide in toluene, the cerium(IV) heterobimetallic polymer [Ce2(Me2pz)6(OtBu)4K2]∞ (9) was isolated. In the Ln3O and the Ln4O cages, the Ln atoms have triangular and distorted tetrahedral arrangements about the central oxygen, respectively. The relationship of the alkali metals to the central oxygen varies considerably. Thus in 2 a, 2 b, there is no bonding, in 3 a, both K atoms interact weakly, in 3 b one of the two Li atom is bound, in 3 d, 4, one of three K atoms in bound, whilst in 5–7, both K atoms are bound. All metals are bound to the cages by a variety of pyrazolate binding modes, with up to five different exhibited in some structures, and a new coordination mode, μ4-1κ(N):2κ(N′):η5:η5, was observed in two complexes. In the structure of 2 c, the coordinated Me2pzH ligand binds to two metals through a single nitrogen, the first time this has been observed for a pyrazole donor. The complex 9 is polymeric with all metals bridged by butoxide donors as well as by Me2pz groups
Novel plant-derived compounds modulate gut microbiome dysbiosis in colitis mice: A potential therapeutic avenue for inflammatory bowel disease
No full textInflammatory bowel disease (IBD) is a chronic, multifactorial disorder of the gastrointestinal tract, often associated with dysbiosis in gut microbiota. While the exact cause of IBD remains unclear, alterations in gut microbiome composition and function are recognised as key contributors to IBD pathogenesis. Natural compounds with anti-inflammatory properties are increasingly explored as potential therapeutic options for IBD. This study evaluated the therapeutic effects of two newly isolated galloyl glucosides—galloyl-lawsoniaside A (comp-4) and uromyrtoside (comp-6)—alongside dexamethasone (DEX) on microbiome regulation in a 2, 4, 6-Trinitrobenzene sulfonic acid (TNBS)-induced colitis mouse model. We employed PacBio HiFi full-length 16S rRNA gene sequencing on mouse colon tissue to assess changes in the intestinal microbiome and its associated functional pathways. TNBS-induced colitis significantly altered microbial composition, increasing the abundance of Acutalibacter muris, Monoglobus pectinilyticus, Streptococcus pneumoniae, Parabacteroides merdae, and Haemophilus influenzae, while decreasing Staphylococcus ureilyticus and Mailhella massiliensis. Treatment with comps 4 and 6 effectively restored the imbalanced microbiota. Functional pathway analysis revealed that colitis reduced microbial pathways, including peptidoglycan biosynthesis and the Bifidobacterium shunt. These disruptions were restored following treatment with our plant-derived compounds. Functional improvements were likely associated with reduced IL-6 production and restoring intestinal barrier integrity. Notably, comp-4 exhibited the most pronounced therapeutic efficacy across both microbial and host-associated parameters. In silico docking further supported the anti-inflammatory and immunomodulatory potential of these compounds. Together, our findings highlight the interplay between microbial function and host immunity in IBD and identify plant-derived galloyl glucosides as promising candidates for microbiome-targeted IBD therapeutics
Continuous Time Markov Chain for Smartwatch Sensors
No full textTime-series forecasting is essential for predicting events in the future and for tracking objects. The conventional recurrent neural network model needs to pad the target with zeros when handling long inputs, resulting in a loss in accuracy. Recently, it was proposed to divide a time series input into patches and merge the learned weights. However, such a model is difficult to interpret. In this article, we consider a mixture of continuous and discrete Markov states to model long-range time dependencies. For example, in a vehicle, each gear level can be a discrete state and the throttle input is continuously controlled to maximise the efficiency of the engine. Data collected from the sensor is prone to noise due to component faults or external disturbances. Hence, we apply a stability constraint to select samples for training. We validate our algorithm on three datasets: (1) Apple Watch, (2) Car engine and (3) Election tweets. On all datasets, we achieve an improvement in the range of 5%–20% in the F-measure. Furthermore, the features learned are easy to explain in terms of real-world scenarios
The influence of rainbow trout on dwarf galaxiid habitat preferences
No full textIntroduced salmonids are a major threat to New Zealand’s non-migratory galaxiids, yet evidence for predator-driven habitat shifts remains limited. We experimentally tested whether dwarf galaxiids (Galaxias divergens) altered habitat use in response to rainbow trout (Oncorhynchus mykiss) presence or odour. Two habitat contrasts were offered: coarse versus fine substrate and open versus vegetated cover, under three predator treatments (trout-present, trout-odour-only, trout-absent). Generalised linear mixed models showed no significant effects of trout treatment on galaxiid habitat choice in either experiment. Substrate use was stable, with a consistent preference for coarse substrate regardless of predator cues, while vegetation cover had no detectable influence on behaviour. These results suggest that trout presence is unlikely to deter dwarf galaxiids from entire river reaches, but their limited behavioural response may leave them more exposed to predation where refuge is scarce. Habitat enhancement, particularly maintaining coarse substrate and reducing fine sediment, is likely to support the resilience of this short-lived, r-selected species
Developing an evidence-based pedagogical framework through investigation of current practice in teaching employability skills inherent to online groupwork
No full textTeaching implicit employability skills in higher education is challenged by the dearth of scholarly literature and institutional structures promoting and supporting a common pedagogical approach. A need to gather empirical evidence of current pedagogical approaches exists so that a pedagogical framework can be developed to support teaching academics in their design and facilitation of integrative teaching. To achieve an empirically evidenced framework this research employs a grounded theory methodology to examine the teaching of online collaboration (online groupwork) skills in the context of online undergraduate business programs. This paper reports on pedagogical content knowledge data analysed from in-depth interviews of online teaching business academics. Pedagogical concepts and related strategies are discovered, educational theories supporting pedagogical concepts are discussed, and a framework is proposed
Formation and Duration of Partnerships
No full text[Extract] Partnership agreements or articles, as they are commonly known, regulate the relationship between partners. The partnership relationship is also regulated by the partnership legislation. However, certain provisions of the partnership legislation will not apply if the partnership agreement contains provisions that contradict them