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Summary Control of white grubs, the sporadic root-feeding larvae of scarabid beetles, is difficult due to their cryptic nature and resistance to chemical insecticides. Potential exists for the use of entomopathogenic nematodes (EPN) for such control. The successful infection of white grubs by EPN, however, is limited by the white grubs’ innate reduced susceptibility in form of behavioural, morphological and physiological defences. This study aimed to determine the different physiological defence mechanisms of white grubs against attack by EPN. The white grub species, Pegylis sommeri and Schizonycha affinis, which were previously found to have a low level of susceptibility to EPN, and Maladera sp. 4, which had previously shown a relative high level of susceptibility, were examined. The ability of the EPN to penetrate the white grubs and of the EPN symbiotic bacteria to grow inside the insect haemolymph, the encapsulation rates, as well as the nematode growth inside the insect haemolymph, were determined. The results showed that the ability of the nematodes to penetrate white grubs, the encapsulation rates and growth in the haemolymph varied between EPN and white grub species. The different species of the EPN symbiotic bacteria were able to grow in the haemolymph of all the white grub species tested. The results indicate that the white grub species investigated tended to resist the initial penetration of most of the EPN studied, thus avoiding infection.

Previous studies suggested that contact pathway factors drive thrombosis in mechanical circulation. We used a rabbit model of veno-arterial extracorporeal circulation (VA-ECMO) to evaluate the role of factors XI and XII in ECMO-associated thrombosis and organ damage. Factors XI and XII (FXI, FXII) were depleted using established antisense oligonucleotides before placement on a blood-primed VA-ECMO circuit. Decreasing FXII or FXI to < 5% of baseline activity significantly prolonged ECMO circuit lifespan, limited the development of coagulopathy, and prevented fibrinogen consumption. Histological analysis suggested that FXII depletion mitigated interstitial pulmonary edema and hemorrhage whereas heparin and FXI depletion did not. Neither FXI nor FXII depletion was associated with significant hemorrhage in other organs. In vitro analysis showed that membrane oxygenator fibers (MOFs) alone are capable of driving significant thrombin generation in a FXII- and FXI-dependent manner. MOFs also augment thrombin generation triggered by low (1 pM) or high (5 pM) tissue factor concentrations. However, only FXI elimination completely prevented the increase in thrombin generation driven by MOFs, suggesting MOFs augment thrombin-mediated FXI activation. Together, these results suggest that therapies targeting FXII or FXI limit thromboembolic complications associated with ECMO. Further studies are needed to determine the contexts wherein targeting FXI and FXII, either alone or in combination, would be most beneficial in ECMO. Moreover, studies are also needed to determine the potential mechanisms coupling FXII to end-organ damage in ECMO.

Genomic diversity is a fundamental component of Earth’s total biodiversity, and requires explicit consideration in efforts to conserve biodiversity. To conserve genomic diversity, it is necessary to measure its spatial distribution, and quantify the contribution that any intraspecific evolutionary lineages make to overall genomic diversity. Here, we describe the range-wide population genomic structure of a threatened Australian rodent, the black-footed tree-rat (Mesembriomys gouldii), aiming to provide insight into the timing and extent of population declines across a large region with a dearth of long-term monitoring data. By estimating recent trajectories in effective population sizes at four localities, we confirm widespread population decline across the species’ range, but find that the population in the peri-urban area of the Darwin region has been more stable. Based on current sampling, the Melville Island population made the greatest contribution to overall allelic richness of the species, and the prioritisation analysis suggested that conservation of the Darwin and Cobourg Peninsula populations would be the most cost-effective scenario to retain more than 90% of all alleles. Our results broadly confirm current sub-specific taxonomy, and provide crucial data on the spatial distribution of genomic diversity to help prioritise limited conservation resources. Along with additional sampling and genomic analysis from the far eastern and western edges of the black-footed tree-rat distribution, we suggest a range of conservation and research priorities that could help improve black-footed tree-rat population trajectories at large and fine spatial scales, including the retention and expansion of structurally complex habitat patches.

The control of white grub (Coleoptera: Scarabaeidae) pests of sugarcane and forest plantations is difficult due to their cryptic nature and resistance to chemicals. This study evaluated the potential use of entomopathogenic nematodes (EPNs) as an alternative control method. Laboratory bioassays were performed with 12 locally isolated EPN species to determine the susceptibility of third instar larvae of the white grubs Schizonycha affinis Boheman, Pegylis sommeri Burmeister, Monochelus sp. and Maladera sp. 4. Concentration trials to determine lethal dosages for three of the white grub species were performed using Heterorhabditis zealandica Poinar MJ2C. Bioassays were performed to determine whether nematodes could develop inside the cadavers of S. affinis and P. sommeri as these had shown the lowest susceptibility to EPNs. The mortality percentage of the white grubs, although varying significantly, was found to be low for most of the EPN species, except H. zealandica. The highest percentage mortality of white grubs was observed at four weeks post inoculation with the rate of mortality being highest in the first week. Schizonycha affinis had the lowest LD50 of 38 Infective juveniles (IJs) per larva after 28 days, compared to Maladera sp. 4, with 284 IJs per larva, and P. sommeri, with 1035 IJs per larva. The dissection of insect cadavers revealed possible limiting factors for low susceptibility, due to the nematodes and their associated symbiotic bacteria’s inability to infect the insect haemocoel, with no EPNs being found inside some of the cadavers.

Morse taper junction tribocorrosion is recognized as an important failure mode in total hip arthroplasty. Although taper junctions are used in almost all shoulder arthroplasty systems currently available in the United States, with large variation in design, limited literature has described comparable analyses of taper damage in these implants. In this study, taper junction damage in retrieved reverse total shoulder arthroplasty (RTSA) implants was assessed and analyzed.Fifty-seven retrieved RTSAs with paired baseplate and glenosphere components with Morse taper junctions were identified via database query; 19 of these also included paired humeral stems and trays or spacers with taper junctions. Components were graded for standard damage modes and for fretting and corrosion with a modified Goldberg-Cusick classification system. Medical records and preoperative radiographs were reviewed. Comparative analyses were performed assessing the impact of various implant, radiographic, and patient factors on taper damage.Standard damage modes were commonly found at the evaluated trunnion junctions, with scratching and edge deformation damage on 76% and 46% of all components, respectively. Fretting and corrosion damage was also common, observed on 86% and 72% of baseplates, respectively, and 23% and 40% of glenospheres, respectively. Baseplates showed greater moderate to severe (grade ≥ 3) fretting (43%) and corrosion (27%) damage than matched glenospheres (fretting, 9%; corrosion, 13%). Humeral stems showed moderate to severe fretting and corrosion on 28% and 30% of implants, respectively; matched humeral trays or spacers showed both less fretting (14%) and less corrosion (17%). On subgroup analysis, large-tapered implants had significantly lower summed fretting and corrosion grades than small-tapered implants (P .001 for both) on glenospheres; paired baseplate corrosion grades were also significantly lower (P = .031) on large-tapered implants. Factorial analysis showed that bolt reinforcement of the taper junction was also associated with less fretting and corrosion damage on both baseplates and glenospheres. Summed fretting and corrosion grades on glenospheres with trunnions (male) were significantly greater than on glenospheres with bores (female) (P .001 for both).Damage to the taper junction is commonly found in retrieved RTSAs and can occur after only months of being implanted. In this study, tribocorrosion predominantly occurred on the taper surface of the baseplate (vs. glenosphere) and on the humeral stem (vs. tray or spacer), which may relate to the flexural rigidity difference between the titanium and cobalt-chrome components. Bolt reinforcement and the use of large-diameter trunnions led to less tribocorrosion of the taper junction. The findings of this study provide evidence for the improved design of RTSA prostheses to decrease tribocorrosion.

Advances in photocontrolled polymerizations have expanded the scope of polymer architectures and structures that can be synthesized for various applications. The majority of these polymerizations have been developed for radical processes, which limits the diversity of monomers that can be used in macromolecular design. More recent developments of photocontrolled cationic polymerizations have taken a step toward addressing this limitation and have expanded the palette of monomers that can be used in stimuli-regulated polymerizations, enabling the synthesis of previously inaccessible polymeric structures. This Account will detail our group's studies on cationic polymerization processes where chain growth is regulated by light and highlight how these methods can be combined with other stimuli-controlled polymerizations to precisely dictate macromolecular structure.Photoinitiated cationic polymerizations are well-studied and important processes that have control over initiation. However, we wanted to develop systems where we had spatiotemporal control over both polymer initiation and chain growth. This additional command over the reaction provides the ability to manipulate the growing polymer with an external stimulus during a polymerization, which can be used to control structure. To achieve this goal, we set out to develop a method to photoreversibly generate a cation at a growing chain end that could participate in a controlled polymerization process. We took inspiration from previous work on cationic degenerate chain transfer polymerizations of vinyl ethers that used thiocarbonylthio chain transfer agents. These polymerizations were initiated by a strong acid and gave well-defined poly(vinyl ether)s. We posited that we could remove the acid initiator in these systems and reversibly oxidize the thiocarbonylthio chain ends in these reactions with a photocatalyst to give a photocontrolled cationic polymerization of vinyl ethers. This Account will focus on our journey to discover cationic photocontrolled polymerizations. We will summarize our initial developments and detail our mechanistic understanding of these reactions using both organic and inorganic based photocatalysts, and we will outline more recent efforts to expand cationic degenerate chain transfer polymerizations to other thioacetal initiators. Finally, we will detail how these photocontrolled cationic polymerizations can be used to switch monomer selectivity

OBJECTIVES: High energy long bone fractures with critical bone loss are at risk for nonunion without strategic intervention. We hypothesize that a synthetic membrane implanted at a single stage improves bone healing in a preclinical nonunion model. METHODS: Using standard laboratory techniques, microspheres encapsulating bone morphogenic protein-2 (BMP2) or platelet derived growth factor (PDGF) were designed and coupled to a type 1 collagen sheet. Critical femoral defects were created in rats and stabilized by locked retrograde intramedullary nailing. The negative control group had an empty defect. The induced membrane group (positive control) had a polymethylmethacrylate spacer inserted into the defect for four weeks and replaced with a bare polycaprolactone/beta-tricalcium phosphate (PCL/β-TCP) scaffold at a second stage. For the experimental groups, a bioactive synthetic membrane embedded with BMP2, PDGF or both enveloped a PCL/β-TCP scaffold was implanted in a single stage. Serial radiographs were taken at 1, 4, 8, and 12 weeks postoperatively from the definitive procedure and evaluated by two blinded observers using a previously described scoring system to judge union as primary outcome. RESULTS: All experimental groups demonstrated better union than the negative control (p=0.01). The groups with BMP2 incorporated into the membrane demonstrated higher average union Mehta scores than the other groups (p=0.01). The induced membrane group performed similarly to the PDGF group. Complete union was only demonstrated in groups with BMP2-eluting membranes. CONCLUSIONS: A synthetic membrane comprised of type 1 collagen embedded with controlled release BMP2 improved union of critical bone defects in a preclinical nonunion model.

Supplementary Figure 1 from Transcription Factor Stat5 Knockdown Enhances Androgen Receptor Degradation and Delays Castration-Resistant Prostate Cancer Progression In vivo

Signal transducer and activator of transcription 5 (Stat5) plays an important role in the transition of prostate cancer (PCa) to its castrate-resistant state. Pharmacologic targeting of Stat5 is a rational approach to delay castrate-resistant progression, in part, because Stat5 cooperates with the androgen receptor (AR) to promote PCa progression. Immunostaining of tissue microarrays was used to correlate Stat5 expression with Gleason grade and to characterize changes in treatment-naive and androgen-deprived human PCa. Potency of a Stat5 antisense oligonucleotide (ASO) on Stat5 knockdown, cell growth, and apoptosis was assessed in LNCaP, C4-2, and DU145 cells. Effects of Stat5 knockdown on AR activity and stability was assessed using a PSA transactivation-luciferase assay and cyclohexamide plus MG132 treatment, respectively. LNCaP tumor-bearing mice were castrated and randomly assigned to treatment with Stat5-ASO or controls. Here, we show that the frequency of Stat5 expression is significantly increased in high Gleason grade as well as in hormone-treated PCa. Also, specific knockdown of Stat5 with ASO abrogates androgen-induced AR nuclear translocation and PSA transactivation despite R1881 stimulation. Moreover, Stat5 knockdown destabilizes AR, which leads to AR degradation via the proteasome. Shown for the first time as a preclinical proof-of-principle, Stat5 knockdown with Stat5-ASO significantly delays CRPC tumor progression in vivo. Thereby, we are able to recapitulate our in vitro results by reducing serum PSA and expression levels of target proteins in the xenograft tumors. Mol Cancer Ther; 10(2); 347–59. ©2011 AACR.

Postfire resprouting (R+) and recruitment from seed (S+) are common resilience traits in Australian ecosystems. We classified 2696 woody Australian taxa as R+ or not (R−) and as S+ or not (S−). The proportions of these traits in Australian ecosystems were examined in relation to fire regimes and other ecological correlates, and by trait mapping on a phylogeny scaled to time. Resprouting mapped as an ancestral trait. Postfire reseeding recruitment, while ancient, is more taxonomically restricted and has evolved independently several times. Nevertheless, both R+ and S+ are common in most clades, but negatively correlated at the ecosystem level indicating an evolutionary trade-off related to differences in the severity of fire regimes, determined in part by ecosystem productivity. Thus, R+ was associated with persistence in ecosystems characterised by higher productivity and relatively frequent surface fires of moderate to low severity (fire-productivity hypothesis). S+, the fire-stimulated recruitment by seed, occurred in ecosystems characterised by infrequent but intense crown-fire and topkill, reducing competition between postfire survivors and recruits (fire-resource-competition hypothesis). Consistently large proportions of R+ or S+ imply fire has been a pervasive evolutionary selection pressure resulting in highly fire-adapted and fire-resilient flora in most Australian ecosystems.

Cationic RAFT of vinyl ethers was performed without reagent purification and under ambient conditions by utilizing a PCCP acid initiator with a HBD catalyst. Despite inherent nucleophiles, the system retained high chain end fidelity and modularity.

Table of differentially expressed genes from RNA-seq analysis of in vitro stimulation of KPC2 cells with and without thrombin.

Supplemental Figure 3. AR full length was highly expressed in nucleus of ENZ-R compared to CR LNCaP xenograft tumors.

Supplemental Figure 5. AR-V7 enhances AR transactivation in ENZ-R cells.

Supplemental Figure 4. Effects of AR-ASO on AR full length and AR-V7 levels in parental LNCaP and ENZ-R MR1F cells.

Supplemental Figure Legends and Mathods. Description of supplemental figure contents and methods used in the related studies.

Supplemental Figure 2. AR and mutation F876S status in ENZ-R LNCaP cells and xenografts.

supplemental Table 1. A list of primers used in the quantitative real-time PCR in this study.

The sonic hedgehog (Shh) pathway contributes to the initiation and progression of tumors with various origins when aberrantly activated. In this study, we investigated if the Shh pathway is important for the proliferation of hepatocellular carcinoma (HCC) cells and also began to identify which components of the pathway play a pivotal role in the biology of HCC. Expression levels of components in the pathway were measured, and glioma-associated oncogene (Gli) 2 levels were found to be considerably higher in human HCC lines compared with normal liver. Gli2 levels were also higher in tumor tissue from HCC patients compared with normal liver. Antisense oligonucleotides (ASO) were used to specifically down-regulate Gli2, and this led to decreased proliferation of various HCC cell lines. However, inhibition of Gli1 and Gli3 with ASOs did not decrease proliferation in most HCC cell lines and inhibitors targeting the upstream components of the pathway, including smoothened (Smo), displayed antiproliferative effects in only a subset of HCC cell lines. Moreover, in cancer cells harboring Smo mutations or unresponsive to the Smo inhibitor 3-keto-N-aminoethylaminoethylcaproyldihydrocinnamoyl cyclopamine, the Gli2 ASO was still able to inhibit proliferation. The importance of Gli2 in HCC proliferation was further confirmed by the changes in expression levels of genes, such as Bcl-2, c-Myc, and p27, following suppression of Gli2 expression. Taken together, these results suggest that, among the Gli transcription factors, Gli2 plays a predominant role in the proliferation of HCC cells and the suppression of Gli2 expression may provide a useful therapeutic option for the treatment of HCC. [Cancer Res 2007;67(8):3583–93]

Supplemental Figure 1. Comparison of tumor growth following injection of MC38 cells

Supplemental Figure 2. Tumor growth was similar in FXIII-/- (n = 6) and control (n = 8) male mice following injection of MC38 cells into dorsal subcutis as measured by serial calipation and tumor mass at sacrifice.

Thrombin-mediated proteolysis is a major determinant of metastasis, but is not universally important for primary tumor growth. Here, we report that colorectal adenocarcinoma represents one important exception whereby thrombin-mediated functions support both primary tumor growth and metastasis. In contrast with studies of multiple nongastrointestinal cancers, we found that the growth of primary tumors formed by murine and human colon cancer cells was reduced in mice by genetic or pharmacologic reduction of circulating prothrombin. Reduced prothrombin expression was associated with lower mitotic indices and invasion of surrounding tissue. Mechanistic investigations revealed that thrombin-driven colonic adenocarcinoma growth relied upon at least two targets of thrombin-mediated proteolysis, protease-activated receptor-1 (PAR-1) expressed by stromal cells and the extracellular matrix protein, fibrinogen. Colonic adenocarcinoma growth was reduced in PAR-1–deficient mice, implicating stromal cell-associated PAR-1 as one thrombin target important for tumor outgrowth. Furthermore, tumor growth was dramatically impeded in fibrinogen-deficient mice, offering the first direct evidence of a critical functional role for fibrinogen in malignant tumor growth. Tumors harvested from fibrinogen-deficient mice displayed a relative reduction in cell proliferative indices, as well as increased tumor necrosis and decreased tumor vascular density. Collectively, our findings established a functional role for thrombin and its targets PAR-1 and fibrinogen in the pathogenesis of colonic adenocarcinoma, supporting tumor growth as well as local invasion and metastasis. Cancer Res; 75(19); 4235–43. ©2015 AACR.

Supplementary Table 1 from Selective Down-Regulation of Glioma-Associated Oncogene 2 Inhibits the Proliferation of Hepatocellular Carcinoma Cells

A critical step towards reducing the incidence of extinction is to identify and rank the species at highest risk, while implementing protective measures to reduce the risk of extinction to such species. Existing global processes provide a graded categorisation of extinction risk. Here we seek to extend and complement those processes to focus more narrowly on the likelihood of extinction of the most imperilled Australian birds and mammals. We considered an extension of existing IUCN and NatureServe criteria, and used expert elicitation to rank the extinction risk to the most imperilled species, assuming current management. On the basis of these assessments, and using two additional approaches, we estimated the number of extinctions likely to occur in the next 20 years. The estimates of extinction risk derived from our tighter IUCN categorisations, NatureServe assessments and expert elicitation were poorly correlated, with little agreement among methods for which species were most in danger-highlighting the importance of integrating multiple approaches when considering extinction risk. Mapped distributions of the 20 most imperilled birds reveal that most are endemic to islands or occur in southern Australia. The 20 most imperilled mammals occur mostly in northern and central Australia. While there were some differences in the forecasted number of extinctions in the next 20 years among methods, all three approaches predict further species loss. Overall, we estimate that another seven Australian mammals and 10 Australian birds will be extinct by 2038 unless management improves.

The ability to fabricate polymeric materials with spatially controlled physical properties has been a challenge in thermoset manufacturing. To address this challenge, this work takes advantage of a photoswitchable polymerization that selectively incorporates different monomers at a growing chain by converting from cationic to radical polymerizations through modulation of the wavelength of irradiation. By regulating the dosage and wavelength of light applied to the system, the mechanical properties of the crosslinked material can be temporally and spatially tuned. Furthermore, photopatterning can be achieved both on the macroscale and the microscale, enabling precise spatial control of crosslink density that results in high-resolution control over mechanical properties.

Two introduced carnivores, the European red fox Vulpes vulpes and domestic cat Felis catus, have had extensive impacts on Australian biodiversity. In this study, we collate information on consumption of Australian birds by the fox, paralleling a recent study reporting on birds consumed by cats. We found records of consumption by foxes on 128 native bird species (18% of the non-vagrant bird fauna and 25% of those species within the fox’s range), a smaller tally than for cats (343 species, including 297 within the fox’s Australian range, a subset of that of the cat). Most (81%) bird species eaten by foxes are also eaten by cats, suggesting that predation impacts are compounded. As with consumption by cats, birds that nest or forage on the ground are most likely to be consumed by foxes. However, there is also some partitioning, with records of consumption by foxes but not cats for 25 bird species, indicating that impacts of the two predators may also be complementary. Bird species ≥3.4 kg were more likely to be eaten by foxes, and those

Climate change is driving changes in fire frequency and intensity, making it more urgent for conservation managers to understand how species and ecosystems respond to fire. In tropical monsoonal savannas – Earth’s most fire-prone landscapes – ecological fire management aims to prevent intense wildfires late in the dry season through prescribed low-intensity fire early in the dry season. Riparian habitats embedded within tropical savannas represent critical refuges for biodiversity, yet are particularly sensitive to fire. Better understanding of the impact of fire – including prescribed burns – on riparian habitats is therefore key, but requires long-term detailed post-fire monitoring of species’ demographic rates, as effects may persist and/or be delayed.Here, we quantify the multi-year impacts of prescribed low-intensity and high-intensity fire on the density, survival, reproduction and dispersal of the threatened western purple-crowned fairy-wren (Malurus coronatus coronatus), in an exceptionally well-studied individually-marked population.Following low-intensity fire, bird density was reduced in the burnt compared to adjacent unburnt riparian habitat for at least 2.5 years. This was a result of reduced breeding success and recruitment for two years immediately following the fire, rather than mortality of adults or dispersal away from burnt habitat.In contrast, a high-intensity fire (in a year with low rainfall) resulted in a sharp decline in population density 2-8 months after the fire, with no signs of recovery after 2.5 years. The decline in density was due to post-fire adult mortality, rather than dispersal. Breeding success of the (few) remaining individuals was low but not detectably lower than in unburnt areas, likely because breeding success was poor overall due to prevailing dry conditions.Hence, even if there is no or very low mortality during fire, and no movement of birds away from burnt areas post-fire, both low- and high-intensity fire in the riparian zone result in reduced population density. However, the mechanism by which this occurs, and recovery time, differs with fire intensity. To minimise the impacts of fire on riparian zones in tropical savannas, we suggest employing low-intensity prescribed burns shortly after the breeding season in years with good rainfall.

Context Invasive species are a major cause of biodiversity loss across much of the world, and a key threat to Australia’s diverse reptile fauna. There has been no previous comprehensive analysis of the potential impact of the introduced European red fox, Vulpes vulpes, on Australian reptiles. Aims We seek to provide an inventory of all Australian reptile species known to be consumed by the fox, and identify characteristics of squamate species associated with such predation. We also compare these tallies and characteristics with reptile species known to be consumed by the domestic cat, Felis catus, to examine whether predation by these two introduced species is compounded (i.e. affecting much the same set of species) or complementary (affecting different groups of species). Methods We collated records of Australian reptiles consumed by foxes in Australia, with most records deriving from fox dietary studies (tallying >35 000 samples). We modelled presence or absence of fox predation records against a set of biological and other traits, and population trends, for squamate species. Key results In total, 108 reptile species (~11% of Australia’s terrestrial reptile fauna) have been recorded as consumed by foxes, fewer than that reported for cats (263 species). Eighty-six species have been reported to be eaten by both predators. More Australian turtle species have been reported as consumed by foxes than by cats, including many that suffer high levels of predation on egg clutches. Twenty threatened reptile species have been reported as consumed by foxes, and 15 by cats. Squamate species consumed by foxes are more likely to be undergoing population decline than those not known to be consumed by foxes. The likelihood of predation by foxes increased with squamate species’ adult body mass, in contrast to the relationship for predation by cats, which peaked at ~217 g. Foxes, but not cats, were also less likely to consume venomous snakes. Conclusions The two introduced, and now widespread, predators have both compounding and complementary impacts on the Australian reptile fauna. Implications Enhanced and integrated management of the two introduced predators is likely to provide substantial conservation benefits to much of the Australian reptile fauna.

Tree hollows are a critical resource for many arboreal vertebrates, including many threatened species. In northern Australia’s vast tropical savannas, arboreal mammals are of particular conservation concern, as many have exhibited rapid population declines in recent decades. To understand the extent to which arboreal vertebrates compete for tree hollows in these savannas, we used motion-activated cameras to estimate rates of hollow visitation (i.e. individuals seen at the hollow entrance) and hollow use (i.e. individuals seen entering or exiting a hollow) by all vertebrate species at 29 hollows over a nine-month wet season period in the tropical savanna of Melville Island, Australia. We assessed the frequency of interactions between vertebrate species at the tree hollows. We recorded 21 vertebrate species visiting hollows, with larger hollows most frequently visited: 84% with entrance diameter > 10 cm. Larger-bodied mammal species were more likely to use larger hollows, in larger trees, at greater heights. However, smaller-bodies species also visited and used large hollows. The brush-tailed rabbit-rat (Conilurus penicillatus) used relatively shallow hollows close to the ground, and these hollows were most frequently visited by monitors (Varanus spp.) and snakes. This arboreal rodent has declined severely in recent decades, most likely due to predation by feral cats, and it is noteworthy that their hollow selection behaviour may be associated with increased predation risk. Our study highlights the importance of large tree hollows for a range of taxa in the tropical savannas of northern Australia and the potential impact of reductions in the density of large hollows on hollow-dependent species. Frequent, intense fires are a threat to large hollow-bearing trees, with appropriate fire management needed to conserve this resource and help to stem mammal declines.

Despite the ongoing collapse of native mammal populations across northern Australia, the paucity of robust estimates of population density limits our capacity to identify and understand population change. Here we aimed to provide the first estimates of native mammal density on the Tiwi Islands – one of Australia’s largest remaining refuge areas for native mammals. We conducted intensive live-trapping at four sites that represent varying combinations of fire frequency, feral cat density and feral herbivore presence. We used spatially-explicit capture-recapture models to investigate the density of common brushtail possum (Trichosurus vulpecula) and northern brown bandicoot (Isoodon macrourus). Compared with mainland northern Australia, populations of common brushtail possum and northern brown bandicoot have remained relatively healthy on the Tiwi Islands. Common brushtail possum density was significantly higher on Bathurst Island (1.06 possum ha−1) compared with Melville Island (0.32 possum ha−1), whereas northern brown bandicoot density varied across all four sites (ranging from 0.04 to 0.34 bandicoot ha−1). Unexpectedly, the very frequently burnt Ranku site (Bathurst Island) continues to support healthy populations of both species. These density estimates provide critical information for identifying and understanding future population change for two species that have suffered marked declines across the Australian monsoon tropics. Although the lack of replication limits our ability to draw conclusions regarding the ecological constraints of these mammal populations, our density observations align with a recent conceptual model postulating that the persistence of native mammal populations across northern Australian savannas reflects a complex, but spatially-variable interplay of ‘bottom-up’ and ‘top-down’ processes.

Background To report mid-term clinical outcomes after radial head arthroplasty for terrible-triad fracture dislocations. Methods Fourteen patients with terrible triad fracture dislocations treated acutely with arthroplasty and minimum 3-year follow-up. Mayo Elbow Performance Scale (MEPS) and QuickDASH scores. Results All patients achieved excellent (58%) or good (42%) results on the MEPS. Average QuickDASH score was 9.1 (range 0-25). Reoperation rate was 28%. Conclusions Acute radial head arthroplasty as a treatment for nonreconstructable radial head fractures in the setting of terrible triad elbow injuries demonstrates good midterm functional outcomes. Level of Evidence Level IV; Retrospective Case Series Study

Determining the factors that drive the distributions of threatened species is often critical for informing effective conservation management actions. Species distribution models can be used to distinguish common habitat features shared by limited historical records and identify other areas where a species might persist. In this study, we built a species distribution model for the Endangered and cryptic Kangaroo Island dunnart (Sminthopsis fuliginosus aitkeni). We fitted generalised linear models using incidental records and presence-absence data from surveys between 1969 and 2018. In the models we included the variables rainfall, percentage native vegetation in the surrounding 2 km2, and post-fire vegetation age. The modelling suggested that rainfall and to a lesser extent post-fire vegetation age are good predictors of dunnart occurrence, with dunnart occurrence greatest in areas of high rainfall (>600 mm) and vegetation age classes

Purpose Precontoured plates used to stabilize lateral tibial plateau (LTP) fractures are limited in their ability to raft particular areas of the reconstructed articular surface. These implants also do not fit every individual's bony anatomy and can lead to soft tissue irritation. The purpose of this study was to evaluate fragment specific plate fixation of LTP fractures using generic small and mini fragment constructs. Methods This was a retrospective case series of LTP fractures treated with small fragment tubular and/or mini fragment plate constructs at a single Level I trauma center. Postoperative complications were recorded. Final radiographs were analyzed to determine union and interval subsidence of the articular surface and/or loss of reduction. Results All 19 LTP fractures healed without loss of reduction or implant failure. There was minimal interval subsidence of the LTP in all patients. There were no complications or reoperations for symptomatic implant removal within the given follow-up period. Conclusion Fragment specific fixation of LTP fractures using small and mini fragment plates creates a lower profile construct that reliably maintains fracture reduction to union.

Invasive eucalypt psyllids pose a threat to the long-term production of eucalypts worldwide. In order to reduce their economic impact and further dispersal, classical biological control using Psyllaephagus species has been used successfully. Psyllaephagus wasps are effective and highly specific in their parasitisation towards psyllids. They are usually sourced from the native range of eucalypts, Australia. However, in some incidents they are accidentally introduced alongside their psyllid hosts. The objective of the study was to determine the host specificity of Psyllaephagus blastopsyllae, P. pilosus and P. bliteus using eucalypt-feeding psyllids, Blastopsylla occidentalis, Ctenarytaina eucalypti, Glycaspis brimblecombei and Spondyliaspis cf. plicatuloides. To determine host specificity, the three different species of Psyllaephagus were collected from their respective hosts locally, and five-day-old parasitoids were exposed to non-host psyllid nymphal instars in a choice and non-choice setting. In both choice and non-choice settings, the parasitoids were exposed to various stages of the psyllid nymphal instars. Glycaspis brimblecombei was identified as a potential new host for P. blastopsyllae, and S. cf. plicatuloides was confirmed as an alternate host for P. bliteus. Psyllaephagus pilosus was the only parasitoid to show no interest in the other psyllids tested. All female parasitoids preferred specific nymphal stages that promote parasitoid larval development. Our findings indicate that some Psyllaephagus spp. attack hosts within an ecological niche, whereas others are highly host specific.