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Functionalization of C-H bonds is a key challenge in medicinal chemistry, particularly for fragment-based drug discovery (FBDD) where such transformations require execution in the presence of polar functionality necessary for protein binding. Recent work has shown the effectiveness of Bayesian optimization (BO) for the self-optimization of chemical reactions; however, in all previous cases these algorithmic procedures have started with no prior information about the reaction of interest. In this work, we explore the use of multitask Bayesian optimization (MTBO) in several in silico case studies by leveraging reaction data collected from historical optimization campaigns to accelerate the optimization of new reactions. This methodology was then translated to real-world, medicinal chemistry applications in the yield optimization of several pharmaceutical intermediates using an autonomous flow-based reactor platform. The use of the MTBO algorithm was shown to be successful in determining optimal conditions of unseen experimental C-H activation reactions with differing substrates, demonstrating an efficient optimization strategy with large potential cost reductions when compared to industry-standard process optimization techniques. Our findings highlight the effectiveness of the methodology as an enabling tool in medicinal chemistry workflows, representing a step-change in the utilization of data and machine learning with the goal of accelerated reaction optimization.

XIAP antagonism measurements in HEK293-XIAP-Caspase-9 xenografts

XIAP antagonism in A375 cells in the presence or absence of TNF-α

Preparation of 2-chloro-1-{6-[(4-fluorophenyl)methyl]-5-(hydroxymethyl)-3,3-dimethyl-1H,2H,3H-pyrrolo[3,2-b]pyridin-1-yl}ethan-1-one

Fold induction in secreted cytokine concentrations in PBMC supernatants after IAP antagonist treatment

Because of their roles in the evasion of apoptosis, inhibitor of apoptosis proteins (IAP) are considered attractive targets for anticancer therapy. Antagonists of these proteins have the potential to switch prosurvival signaling pathways in cancer cells toward cell death. Various SMAC-peptidomimetics with inherent cIAP selectivity have been tested clinically and demonstrated minimal single-agent efficacy. ASTX660 is a potent, non-peptidomimetic antagonist of cIAP1/2 and XIAP, discovered using fragment-based drug design. The antagonism of XIAP and cIAP1 by ASTX660 was demonstrated on purified proteins, cells, and in vivo in xenograft models. The compound binds to the isolated BIR3 domains of both XIAP and cIAP1 with nanomolar potencies. In cells and xenograft tissue, direct antagonism of XIAP was demonstrated by measuring its displacement from caspase-9 or SMAC. Compound-induced proteasomal degradation of cIAP1 and 2, resulting in downstream effects of NIK stabilization and activation of noncanonical NF-κB signaling, demonstrated cIAP1/2 antagonism. Treatment with ASTX660 led to TNFα-dependent induction of apoptosis in various cancer cell lines in vitro, whereas dosing in mice bearing breast and melanoma tumor xenografts inhibited tumor growth. ASTX660 is currently being tested in a phase I–II clinical trial (NCT02503423), and we propose that its antagonism of cIAP1/2 and XIAP may offer improved efficacy over first-generation antagonists that are more cIAP1/2 selective. Mol Cancer Ther; 17(7); 1381–91. ©2018 AACR.

Comparison of XIAP activity, cIAP1 activity and selectivity of clinical IAP antagonists

IncuCyte images from neutralization of TNF-α activity with anti-TNF-α experiment in MDA-MB-231 cells

Additional data from ASTX669 in vivo xenograft studies

Few landscape-scale experiments test the effects of predators on the abundance and distribution of prey across habitat gradients. We use the assisted colonization of a top predator, the Tasmanian devil ( Sarcophilus harrisii ), to test the impacts of predation on the abundance, habitat use and temporal activity of a widespread prey species, the omnivorous common brushtail possum ( Trichosurus vulpecula ). Before introduction of devils to Maria Island, Tasmania, Australia, in 2012, possums were abundant in open grasslands as well as forests. Predation by devils caused high mortality of possums in grasslands, but individuals with access to trees had a higher survival probability. Possum abundance declined across the whole island from 2012–2016, as possums disappeared almost completely from grasslands and declined in drier forests with more open understorey. Abundance remained stable in wet forests, which are not preferred habitat for possums but provide better refuge from devils. Abundance and habitat use of possums remained unchanged at a control site on the adjacent Tasmanian mainland, where the devil population was low and stable. This study demonstrates how spatial variation in predator-caused mortality can limit both abundance and habitat breadth in generalist prey species, excluding them entirely from certain habitats.

Fragment-based drug discovery (FBDD) continues to evolve and make an impact in the pharmaceutical sciences. We summarize successful fragment-to-lead studies that were published in 2020. Having systematically analyzed annual scientific outputs since 2015, we discuss trends and best practices in terms of fragment libraries, target proteins, screening technologies, hit-optimization strategies, and the properties of hit fragments and the leads resulting from them. As well as the tabulated Fragment-to-Lead (F2L) programs, our 2020 literature review identifies several trends and innovations that promise to further increase the success of FBDD. These include developing structurally novel screening fragments, improving fragment-screening technologies, using new computer-aided design and virtual screening approaches, and combining FBDD with other innovative drug-discovery technologies.

Context Home-range size and population density characteristics are crucial information in the design of effective wildlife management, whether for conservation or control, but can vary widely among populations of the same species. Aims We investigate the influence of site productivity on home-range size and population density for Australian populations of the native, threatened spotted-tailed quoll (Dasyurus maculatus) and the alien and highly successful feral cat (Felis catus). Methods We use live trapping and fine-scale GPS tracking to determine the home-range size and population density for both species across five sites in Tasmania. Using these data, as well as published estimates for both species from across Australia, we model how these parameters change in response to productivity gradients. We also use the telemetry data to examine the energetic costs of increasing home-range size for both species. Key results For both species, decreasing site productivity correlates with lower population density, and in spotted-tailed quolls and female feral cats, it also correlates with larger home-range sizes. However, the relative magnitude of these changes is different. Feral cats show smaller increases in home-range size but larger decreases in population density relative to spotted-tailed quolls. Our results suggest that these differences may be because increases in home-range size are more costly for feral cats, demonstrated by larger increases in nightly movement for the same increase in home-range area. Conclusions We suggest that knowledge of both home-range size and population density is needed to accurately determine how species respond to habitat productivity, and inform effective management across their geographic range. Implications These results have clear management implications; for example, in our low-rainfall sites, an adult female spotted-tailed quoll requires up to five times the amount of habitat expected on the basis of previous studies, thus dramatically increasing the costs of conservation programs for this threatened native species. Conversely, productivity-driven differences of up to four-fold in feral cat population density would influence the resources required for successful control programs of this invasive species.

Context Invasive predators are a key threat to biodiversity worldwide. In Australia, feral cats are likely to be responsible for many extinctions of native mammal species in the south and centre of the continent. Aims Here we examine the effect of feral cats on native rodent populations in the second of two translocation experiments. Methods In a wild-to-wild translocation, we introduced pale field rats, Rattus tunneyi, whose populations are declining in the wild, into two pairs of enclosures where accessibility by feral cats was manipulated. Key results Individual rats translocated into enclosures accessible to cats were rapidly extirpated after cats were first detected visiting the enclosures. Rats in the enclosure not exposed to cats were 6.2 times more likely to survive than those exposed to cats. Two individual cats were responsible for the deaths of all but 1 of 18 cat-accessible rats. Rats in the site with denser ground cover persisted better than in the site with more open cover. Conclusions These results are consistent with our previous study of a different native rat species in the same experimental setup, and provide further evidence that, even at low densities, feral cats can drive local populations of small mammals to extinction. Implications Effective feral cat control may be necessary to enable recovery of small mammals.

Inhibition of murine double minute 2 (MDM2)-p53 protein-protein interaction with small molecules has been shown to reactivate p53 and inhibit tumor growth. Here, we describe rational, structure-guided, design of novel isoindolinone-based MDM2 inhibitors. MDM2 X-ray crystallography, quantum mechanics ligand-based design, and metabolite identification all contributed toward the discovery of potent in vitro and in vivo inhibitors of the MDM2-p53 interaction with representative compounds inducing cytostasis in an SJSA-1 osteosarcoma xenograft model following once-daily oral administration.

Effective monitoring of mammal species is critical to their management. Thermal cameras may enable more accurate detection of nocturnal mammals than visual observation with the aid of spotlights. We aimed to measure improvements in detection provided by thermal cameras, and to determine how these improvements depended on ambient temperatures and mammal species. We monitored small to medium sized mammals in central Australia, including small rodents, bettongs, bilbies, European rabbits, and feral cats. We conducted 20 vehicle-based camera transects using both a spotlight and thermal camera under ambient temperatures ranging from 10°C to 35°C. Thermal cameras resulted in more detections of small rodents and medium sized mammals. There was no increased benefit for feral cats, likely due to their prominent eyeshine. We found a strong relationship between increased detections using thermal cameras and environmental temperature: thermal cameras detected 30% more animals than conventional spotlighting at approximately 15°C, but produced few additional detections above 30°C. Spotlighting may be more versatile as it can be used in a greater range of ambient temperatures, but thermal cameras are more accurate than visual surveys at low temperatures, and can be used to benchmark spotlight surveys.

Animals alter their habitat use in response to the energetic demands of movement ('energy landscapes') and the risk of predation ('the landscape of fear'). Recent research suggests that animals also select habitats and move in ways that minimise their chance of temporarily losing control of movement and thereby suffering slips, falls, collisions or other accidents, particularly when the consequences are likely to be severe (resulting in injury or death). We propose that animals respond to the costs of an 'accident landscape' in conjunction with predation risk and energetic costs when deciding when, where, and how to move in their daily lives. We develop a novel theoretical framework describing how features of physical landscapes interact with animal size, morphology, and behaviour to affect the risk and severity of accidents, and predict how accident risk might interact with predation risk and energetic costs to dictate movement decisions across the physical landscape. Future research should focus on testing the hypotheses presented here for different real-world systems to gain insight into the relative importance of theorised effects in the field.

Control of invasive predators is a priority to protect island biodiversity. Understanding the responses of other species in multi-species invaded food webs is important to avoid unintended consequences. We use an intensive two-year cat-trapping program in the vicinity of seabird colonies on Bruny Island, Tasmania, to estimate the change in densities of feral cats and investigate the effect of control on the behaviour and abundance of native and invasive mammal species. Cat density before control was extremely high then reduced by 5.4-fold consequent to control. We show a complex but subtle cascade of ecological effects among mesopredator and prey species, with a lagged response to a pulse of bottom-up productivity provided by breeding seabirds. Our study demonstrates that cat density on islands, particularly around seasonally rich food resources such as seabird colonies, can be very high, much higher than on mainland areas, and that control using trapping is effective reducing cat density in this focussed landscape context. Our results highlight the complexity of effects of control of an invasive predator on the broader ecosystem. The top-down effect of cats on the ecosystem was limited but the response of prey indicates a predator effect conditioned by temporal change in bottom-up productivity.

Sympatric species can minimise interspecific competition by spatial avoidance or by altering their temporal activity to reduce encounter rates. The Tasmanian devil (Sarcophilus harrisii), the largest carnivorous marsupial, coexists with the smaller spotted‐tailed quoll (Dasyurus maculatus) in Tasmania, Australia. Quolls may be susceptible to interspecific competition from devils, because they utilise similar habitats, consume similar prey species and are displaced by devils at food sources. Such competition might cause quolls to spatially or temporally avoid devils. To investigate whether spatial or temporal avoidance occurred, we deployed GPS collars on sympatric devils and quolls and conducted a camera survey at a site in northwest Tasmania where the devil population was not affected by devil facial tumour disease. GPS tracking coincided with the lactation period when devils and quolls had young in dens and continued until weaning occurred. We found little spatial segregation of home range and core area placement between devils and quolls and among devils. Quolls showed more spatial segregation within the sexes than between them. Devils had larger home ranges than quolls. Male devils had larger home ranges than females, but there was no difference in home range size between the sexes of quolls. Females of both species travelled significantly further per night than did males. There was moderate temporal partitioning between the two species: devil activity peaked after dusk and devils remained active until the early morning, while quoll activity showed distinct peaks around dusk and dawn. In conclusion, quolls did not spatially avoid devils but moderate temporal partitioning occurred. It is plausible that quolls are active at different times of the diel cycle to reduce encountering devils, but further studies are needed to resolve the cause of this temporal partitioning.

The control of invasive species can have cascading and at times undesirable effects on the wider ecological community. Effective management requires that the ecosystem-wide effects of removing invasive species be understood. We investigated the effects of large-scale rabbit control on the abundance (numerical response) and diet (functional response) of an invasive predator (ferret, Mustela putorius furo) that preys on rabbits (Oryctolagus cuniculus), as well as the subsequent predation pressure experienced by alternative prey species (total response), in New Zealand’s dryland habitats. Following rabbit control, ferret densities declined but surviving ferrets increased their per capita consumption of lizards and invertebrates, two key native prey groups. Rabbit control increased predation pressure on lizards, but reduced it on invertebrates. While rabbit control can negatively impact some groups of alternative prey up to 18 months post-control, it probably benefits them in the longer term because prey-switching by ferrets tended to reduce with time, and regeneration of vegetation previously over-grazed by rabbits is likely to reduce exposure of native prey to predation. While confirming these benefits will require longer-term monitoring, our results support management actions that limit short-term fluctuations in rabbit abundance and maintain them at low abundance.

Like many other Australian mammals, the eastern quoll (Dasyurus viverrinus) was widespread on the Australian mainland but went extinct there during the 20th century. The species remained abundant in Tasmania until a rapid decline occurred from 2001 to 2003, coinciding with a period of unsuitable weather. We provide an updated analysis of eastern quoll population trends in Tasmania by analysing a Tasmania-wide time series of annual spotlight counts (1985-2019). Eastern quolls were widespread and abundant in Tasmania until the early 2000s. A distinct change occurred in the early 2000s in the east and northeast, which led to severe population reductions. However, we present new evidence of an earlier decline in the north (mid-1990s) and a more recent decline around 2009 in the south. Range-wide declines have continued unabated during the last decade, resulting in a ∼67% decline (since the late 1990s) in the area with high quoll abundance. Although the timing of the major decline in the early 2000s coincided with unfavourable weather, the continuing decline and more recent change points suggest other causes are also involved. We can no longer assume that the existence of eastern quolls in Tasmania ensures the species’ long-term survival, highlighting the urgent need to increase efforts to conserve the remaining populations in Tasmania.

Extinctions stemming from environmental change often trigger trophic cascades and coextinctions. Bottom-up cascades occur when changes in the primary producers in a network elicit flow-on effects to higher trophic levels. However, it remains unclear what determines a species' vulnerability to bottom-up cascades and whether such cascades were a large contributor to the megafauna extinctions that swept across several continents in the Late Pleistocene. The pathways to megafauna extinctions are particularly unclear for Sahul (landmass comprising Australia and New Guinea), where extinctions happened earlier than on other continents. We investigated the potential role of bottom-up trophic cascades in the megafauna extinctions in Late Pleistocene Sahul by first developing synthetic networks that varied in topology to identify how network position (trophic level, diet breadth, basal connections) influences vulnerability to bottom-up cascades. We then constructed pre-extinction (-80 ka) network models of the ecological community of Naracoorte, south-eastern Sahul, to assess whether the observed megafauna extinctions could be explained by bottom-up cascades. Synthetic networks showed that node vulnerability to bottom-up cascades decreased with increasing trophic level, diet breadth and basal connections. Extinct species in the Naracoorte community were more vulnerable overall to these cascades than were species that survived. The position of extinct species in the network - tending to be of low trophic level and therefore having relatively narrow diet breadths and fewer connections to plants - made them vulnerable. However, these species also tended to have few or no predators, a network-position attribute that suggests they might have been particularly vulnerable to new predators. Together, these results suggest that trophic cascades and naivety to predators could have contributed to the megafauna extinction event in Sahul.

Movements that extend beyond the usual space use of an animal have been documented in a range of species and are particularly prevalent in arid areas. We present long-distance movement data on five feral cats (Felis catus) GPS/VHF-collared during two different research projects in arid and semi-arid Australia. We compare these movements with data from other feral cat studies. Over a study period of three months in the Ikara-Flinders Ranges National Park, 4 out of 19 collared cats moved to sites that were 31, 41, 53 and 86 km away. Three of the cats were males, one female, their weight was between 2.1 and 4.1 kg. Two of the cats returned to the area of capture after three and six weeks. During the other study at Arid Recovery, one collared male cat (2.5 kg) was relocated after two years at a distance of 369 km from the area of collar deployment to the relocation area. The movements occurred following three years of record low rainfall. Our results build on the knowledge base of long-distance movements of feral cats reported at arid study sites and support the assertion that landscape-scale cat control programs in arid and semi-arid areas need to be of a sufficiently large scale to avoid rapid reinvasion and to effectively reduce cat density. Locally, cat control strategies need to be adjusted to improve coverage of areas highly used by cats to increase the efficiency of control operations.

Calmodulin (CaM) serves as an important Ca(2+) signaling hub that regulates many protein signaling pathways. Recently, it was demonstrated that plant CaM homologs can regulate mammalian targets, often in a manner that opposes the impact of the mammalian CaM. However, the molecular basis of how CaM homologs mutations differentially impact target activation is unclear. To understand these mechanisms, we examined two CaM isoforms found in soybean plants that differentially regulate a mammalian target, calcineurin (CaN). These CaM isoforms, sCaM-1 and sCaM-4 share >90% and ∼78% identity with the mammalian CaM (mCaM), respectively, and activate CaN with comparable or reduced activity relative to mCaM. We used molecular dynamics (MD) simulations and fluorometric assays of CaN-dependent dephosphorylation of MUF-P to probe whether calcium and protein-protein binding interactions are altered by plant CaMs relative to mCaM as a basis for differential CaN regulation. In the presence of CaN, we found that the two sCaMs’ Ca(2+)-binding properties, such as their predicted coordination of Ca(2+) and experimentally measured EC(50) [Ca(2+)] values are comparable to mCaM. Furthermore, the binding of CaM to the CaM binding region (CaMBR) in CaN is comparable among the three CaMs, as evidenced by MD-predicted binding energies and experimentally measured EC(50) [CaM] values. However, mCaM and sCaM-1 exhibited binding with a secondary region of CaN’s regulatory domain that is weakened for sCaM-4. We speculate that this secondary interaction affects the turnover rate (k(cat)) of CaN based on our modeling of enzyme activity, which is consistent with our experimental data. Together, our data describe how plant-derived CaM variants alter CaN activity through enlisting interactions other than those directly influencing Ca(2+)-binding and canonical CaMBR binding, which may additionally play a role in the differential regulation of other mammalian targets.

Calcineurin, also known as protein phosphatase 2B, is a heterodimeric serine threonine phosphatase involved in numerous signaling pathways. During the past 50 years, calcineurin has been the subject of extensive investigation. Many of its cellular and physiological functions have been described, and the underlying biophysical mechanisms are the subject of active investigation. With the abundance of techniques and experimental designs utilized to study calcineurin and its numerous substrates, it is difficult to reconcile the available information. There have been a plethora of reports describing the role of calcineurin in cardiac disease. However, a physiological role of calcineurin in healthy cardiomyocyte function requires clarification. Here, we review the seminal biophysical and structural details that are responsible for the molecular function and inhibition of calcineurin. We then focus on literature describing the roles of calcineurin in cardiomyocyte physiology and disease.

The impacts of invasive predators can be amplified by high densities of invasive prey species. In Australia, hyper abundant rabbit populations lead to high densities of feral cats and correspondingly high impact of cats on native species, especially small mammals. Therefore, it would be expected reducing rabbits could also reduce abundance of cats, and thereby alleviate predation on native small mammals. However, cats might respond to the loss of rabbits by prey-switching to native small mammals, resulting in increased predation on those species. Our aim was to understand the short-term effects of an experimental reduction of rabbit abundance on feral cats and their small-mammal prey in arid South Australia. We reduced the rabbit population in a 37 km2 experimental enclosure by ~ 80%, while monitoring an adjacent unmanipulated area as a control. Cat activity and survival of VHF-collared cats in the enclosure decreased by 40% following the rabbit reduction. Surviving cats increased their consumption of reptiles, birds and invertebrates, but they nevertheless evinced hunger by increased intake of experimentally-supplied sausages. There was no change in either the proportion of cat scats that contained remains of small mammals, or the rate at which video-collared cats were recorded killing small mammals, even though the activity of small mammals declined. Our results demonstrate that individual feral cats prey-switch in response to removal of their primary prey. However, we also show that survival and overall activity of cats decreased, which could result in net, long-term benefits for native prey threatened by cats. Management of feral cats using food lures or baits would also be more effective when introduced prey are scarce, as cats are more likely to eat novel food.

Studies of impacts of fragmentation have focused heavily on measures of species presence or absence in fragments, or species richness in relation to fragmentation, but have often not considered the effects of fragmentation on ranging behavior of individual species. Effective management will benefit from knowledge of the effects of fragmentation on space use by species.We investigated how a woodland specialist, the eastern bettong (Bettongia gaimardi), responded to fragmentation in an agricultural landscape, the Midlands region of Tasmania, Australia. We tested whether individual bettongs could adjust home range size to maintain access to essential habitat across three sites differing in degree of fragmentation.We used GPS tracking to measure the home ranges of individual bettongs. Our models tested the effects of habitat aggregation and habitat amount measured at two radii comparable to a typical core range (250 m) and a typical home range (750 m), and habitat quality and sex on individual home range. We also tested the relationship between fragmentation on woodland used to determine whether individuals could compensate for fragmentation.Depending on the spatial scale of fragmentation measured, bettongs altered their movement to meet their habitat requirements. Our top model suggested that at the core range scale, individuals had smaller ranges when habitat is more aggregated. The second model showed support for habitat amount at the core range, suggesting individuals can occupy larger areas when there is a higher amount of habitat, regardless of configuration.Species that are relatively mobile may be able to compensate for the effects of habitat fragmentation by altering their movement. We highlight that any patch size is of value within a home range and management efforts should focus on maintaining sufficient habitat especially at the core range scale., For a mobile species that can cross gaps, the configuration of patches does not hinder movement given there is sufficient habitat.

Top predators cause avoidance behaviours in competitors and prey, which can lead to niche partitioning and facilitate coexistence. We investigate changes in partitioning of the temporal niche in a mammalian community in response to both the rapid decline in abundance of a top predator and its rapid increase, produced by two concurrent natural experiments: 1) the severe decline of the Tasmanian devil due to a transmissible cancer, and 2) the introduction of Tasmanian devils to an island, with subsequent population increase. We focus on devils, two mesopredators and three prey species, allowing us to examine niche partitioning in the context of intra- and inter-specific competition, and predator-prey interactions. The most consistent shift in temporal activity occurred in devils themselves, which were active earlier in the night at high densities, presumably because of heightened intraspecific competition. When devils were rare, their closest competitor, the spotted-tailed quoll, increased activity in the early part of the night, resulting in increased overlap with the devil's temporal niche and suggesting release from interference competition. The invasive feral cat, another mesopredator, did not shift its temporal activity in response to either decreasing or increasing devil densities. Shifts in temporal activity of the major prey species of devils were stronger in response to rising than to falling devil densities. We infer that the costs associated with not avoiding predators when their density is rising (i.e. death) are higher than the costs of continuing to adopt avoidance behaviours as predator densities fall (i.e. loss of foraging opportunity), so rising predator densities may trigger more rapid shifts. The rapid changes in devil abundance provide a unique framework to test how the non-lethal effects of top predators affect community-wide partitioning of temporal niches, revealing that this top predator has an important but varied influence on the diel activity of other species.

Global declines of large carnivores have reduced the 'landscape of fear' that constrains the behaviour of other species. In recent years, active and passive trophic rewilding have potentially begun restoring these lost top-down controls. The Tasmanian devil Sarcophilus harrisii has declined severely due to a novel transmissible cancer. In response to extinction fears, devils were introduced to the devil-free Maria Island, where their abundance rapidly increased. We tested how this introduction influenced risk-sensitive foraging in the common brushtail possum Trichosurus vulpecula, a major prey species for devils, using giving-up densities (GUDs). Before the introduction of devils, possum GUDs on Maria Island were indistinguishable from the long-diseased region of Tasmania, where devils have been rare since ∼2000. Three years after devil introduction, GUDs were 64% higher on Maria Island than the control region, demonstrating that after an initial period of high mortality, possums quickly adopted risk-sensitive foraging behaviours. Devil activity across Maria Island was variable, leading to a heterogeneous landscape of fear and highlighting that top predators must be at functional densities to elicit behavioural responses from prey. Our study provides strong evidence that top predators modify the behaviour of prey by instilling fear, causing rapid ecological change following recoveries.

Interactions between competing species may be intensified when they are restricted to small patches of remnant habitat, potentially increasing physiological stress in individuals. The effects of interspecific competition on stress in wildlife remain largely unexplored. In Australia, remnant woodlands are often dominated by aggressive honeyeaters, especially the noisy miner (Manorina melanocephala). Harassment of smaller birds by miners may result in their exclusion from suitable woodland habitat. We tested whether the presence of noisy miners is also associated with elevated stress in a model species of small passerine bird, the superb fairy‐wren (Malurus cyaneus). We sampled wrens from six sites, three remnant woodlands with noisy miners and three larger fragments of reserved habitat without noisy miners. Differential white blood cell counts were used to infer levels of chronic stress. We also assessed variation in body condition and the prevalence of blood parasites (Haemoproteus spp.) to test for associations between stress and parasitemia. The mean heterophil‐to‐lymphocyte (H:L) ratio was 1.8 × higher among superb fairy‐wrens living in miner‐dominated woodlands, suggesting higher levels of chronic stress. Individuals with higher stress appeared to be in poorer condition, as indicated by fat scores and residual body mass. Prevalence of blood parasites was generally high and was highest in reserved habitat (59%) where miners were absent. Birds with blood parasites living in these habitats had higher H:L ratios but the intensity of infection and H:L ratio was inversely related. Our results suggest that birds persisting in the presence of noisy miners might experience chronic stress, but further study is necessary to separate the relative importance of noisy miner aggression from other potential stressors in small patches of degraded woodland. Stress induced by interspecific aggression should be considered in future studies of wildlife living in remnant vegetation.

Background The local treatment of extremity sarcomas usually is predicated on a decision between limb salvage and amputation. The manner in which surgical options are presented in the context of shared decision-making may influence this decision. In a population of "simulated" patients-survey respondents presented with a mock clinical vignette and then asked to choose between treatments-we assessed cognitive bias by deliberate alteration of the subjective presentation of the same objective information. Questions/purposes (1) Will the manner in which information is presented to a simulated patient, in the setting of treatment for a bone sarcoma, bias their decision regarding pursuing amputation versus limb salvage? (2) At the time of decision-making, will a simulated patient's personal background, demographics, or mood affect their ultimate decision? Methods Survey respondents (Amazon MTurk platform) were presented with mock clinical vignettes simulating a sarcoma diagnosis and were asked to choose between amputation and limb salvage. Specific iterations were designed to assess several described types of cognitive bias. These scenarios were distributed, using anonymous online surveys, to potential participants aged 18 years or older. Recruitment was geographically restricted to individuals in the United States. Overall, 404 respondents completed the survey. The average age of respondents was 33 years (SD 1.2 years), 60% were male and 40% were female. In all, 12% of respondents worked in healthcare. Each respondent also completed questions regarding his or her demographics and his or her current mood. Associations between the type of bias presented and the respondent's choice of limb salvage versus amputation were examined. Independent sample t-tests were used to compare means. Statistical significance was defined as p Results When amputation was presented as an option to mitigate functional loss (framing bias), more patients chose it than when limb salvage was presented as means for increased functional gains (23% [23 of 100] versus 10% [12 of 118], odds ratio [OR], 2.26; p = 0.010). Older simulated patients were more likely to choose limb salvage when exposed to framing bias versus younger patients (mean age 33 years versus 30 years, p = 0.02). Respondents who were employed in healthcare more commonly chose amputation versus limb salvage when exposed to framing bias (24% [eight of 35] versus 9% [17 of 183]; OR, 2.46; p = 0.02). Those who chose amputation were more likely to score higher on scales that measured depression or negative affect. Conclusions Shared decision-making in orthopaedic oncology represents a unique circumstance in which several variables may influence a patient's decision between limb salvage and amputation. Invoking cognitive bias in simulated patients appeared to affect treatment decisions. We cannot be sure that these findings translate to the experience of actual sarcoma patients; however, we can conclude that important treatment decisions may be affected by cognitive bias and that patient characteristics (in this study, age, healthcare profession, and mood) may be associated with an individual's susceptibility to cognitive bias. We hope these observations will assist providers in the thoughtful delivery of highly charged information to patients facing difficult decisions, and promote further study of this important concept. Level of evidence Level III, economic and decision analyses.