Reducing Overuse by Healthcare Systems: A Positive Deviance Analysis.

BACKGROUND: Healthcare in the USA is increasingly delivered by large healthcare systems that include one or more hospitals and associated outpatient practices. It is unclear what role healthcare systems play in driving or preventing overutilization of healthcare services in the USA. OBJECTIVE: To learn how high-value healthcare systems avoid overuse of services DESIGN: We identified "positive deviant" health systems using a previously constructed Overuse Index. These systems have much lower-than-average overuse of healthcare services. We confirmed that these health systems also delivered high-quality care. We conducted semi-structured interviews with executive leaders of these systems to validate a published framework for understanding drivers of overuse. PARTICIPANTS: Leaders at select healthcare systems in the USA. INTERVENTIONS: None APPROACH: We developed an interview guide and conducted semi-structured interviews. We iteratively developed a code book. Paired reviewers coded and reconciled each interview. We analyzed the interviews by applying constant comparative techniques. We mapped the emergent themes to provide the first empirical data to support a previously developed theoretical framework. KEY RESULTS: We interviewed 15 leaders from 10 diverse healthcare systems. Consistent with important domains from the overuse framework, themes from our study support the role of clinicians and patients in avoiding overuse. The leaders described how they create a culture of professional practice and how they modify clinicians' attitudes to facilitate high-value practices. They also described how their patients view healthcare consumption and the characteristics of their patient populations allowed them to practice high-value medicine. They described the role of quality metrics, insurance plan ownership, and alternative payment model participation as encouraging avoidance of overuse. CONCLUSIONS: Our qualitative analysis of positive deviant health systems supports the framework that is in the published literature, although health system leaders also described their financial structures as another important factor for reducing overuse and encouraging high-value care delivery.

Field assessment of horse-associated genetic markers HoF597 and mtCytb for detecting the source of contamination in surface waters.

We investigated the specificity and sensitivity of two horse-associated markers, HoF597 and Horse mtCytb, and 12 mitochondrial and bacterial markers of six animal species (human, cow, pig, bird, dog, chicken) in the faecal samples of 50 individual horses. Both horse markers were detected in 48 (96%) faecal samples. Cross-reactivity with dog (BacCan545) and pig (P23-2) occurred in 88% and 72% of horse faecal samples, respectively. Several other bacterial and mitochondrial markers of non-target hosts were also detected; however, their specificities were >80%. Analyses of samples from surface waters (n = 11) on or adjacent to properties from which horse faecal samples had been collected showed only the presence of HoF597 but not horse mitochondrial marker. Our data suggest that while bacterial and (or) mitochondrial markers of other animal species may be present in horse faeces, dog and pig markers may predominantly be present in horse faecal samples, which points to their nonspecificity as markers for microbial source tracking. Although HoF597 and Horse mtCytb are highly sensitive and specific for the detection of horse faecal pollution, because of their low numbers, mitochondrial (mtDNA) markers may not be robust for screening surface waters.

Effects of Water Immersion on Squat and Split Squat Kinematics in Older Adults.

This study examined the effect of water immersion on trunk and lower limb kinematics during squat exercises in older participants. A total of 24 active older adults (71.4 ± 5.4 years) performed squats and split squats on land and while partially submerged in water. Inertial sensors (100 Hz) were used to record trunk and lower body kinematics. Water immersion increased the squat depth (squat: p = .028, d = 0.63 and split squat: p = .005, d = 0.83) and reduced the trunk flexion range (squat: p = .006, d = 0.76 and split squat: p < .001, d = 1.35) during both exercises. In addition, water immersion increased the hip range of motion during the split squat (p = .002, d = 0.94). Waveform analyses also indicated differences in the timing of the movements. These results showed that water-based exercise generates a different exercise outcome and appears to provide an alternative option for older adults, enabling exercisers to perform these tasks in a manner not possible on land.

Enterococci populations of a metropolitan river after an extreme flood event: prevalence, persistence and virulence determinants.

We investigated the prevalence, persistence and virulence determinants of enterococci populations in water samples collected over three rounds following an extreme flood event in a metropolitan river. Enterococci (n = 482) were typed using the high resolution biochemical fingerprinting method (PhP typing) and grouped into common (C) or single (S) biochemical phenotypes (BPTs). In all, 23 C-BPTs (72.6% of isolates) were found across the sites. A representative isolate of each C-BPT was identified to the species level and tested for the presence of seven virulence genes (VGs), biofilm formation and resistance to 14 antibiotics. The enterococci concentrations in samples collected during the first two rounds were above national recreational water guidelines. By round three, enterococci concentrations decreased significantly (P < 0.05). However, 11 C-BPTs (55.5% of isolates) persisted across all sampling rounds. E. casseliflavus and E. mundtii were the most common enterococci populations comprising of >57% of all isolates. Ten of the 11 most dominant C-BPTs were resistant to multiple antibiotics and harboured one or more VGs. The high prevalence of antibiotic resistance and VGs among enterococci isolates in this catchment not only provides them with niche advantages but also poses a risk to public health.

Assessing the population dynamics of Escherichia coli in a metropolitan river after an extreme flood event.

We investigated Escherichia coli populations in a metropolitan river after an extreme flood event. Between nine and 15 of the 23 selected sites along the river were sampled fortnightly over three rounds. In all, 307 E. coli were typed using the PhP typing method and were grouped into common (C) or single (S) biochemical phenotypes (BPTs). A representative from each of the 31 identified C-BPTs was tested for 58 virulence genes (VGs) associated with intestinal and extra-intestinal E. coli, resistance to 22 antibiotics, production of biofilm and cytotoxicity to Vero cells. The number of E. coli in the first sampling round was significantly (P < 0.01) higher than subsequent rounds, whereas the number of VGs was significantly (P < 0.05) higher in isolates from the last sampling round when compared to previous rounds. Comparison of the C-BPTs with an existing database from wastewater treatment plants (WWTPs) in the same catchment showed that 40.6% of the river isolates were identical to the WWTP isolates. The relatively high number of VGs and antibiotic resistance among the C-BPTs suggests possessing and retaining these genes may provide niche advantages for those naturalised and/or persistent E. coli populations which may pose a health risk to the community.

Typology of solutions addressing diagnostic disparities: gaps and opportunities.

OBJECTIVES: Diagnostic disparities are preventable differences in diagnostic errors or opportunities to achieve diagnostic excellence. There is a need to summarize solutions with explicit considerations for addressing diagnostic disparities. We aimed to describe potential solutions to diagnostic disparities, organize them into an action-oriented typology with illustrative examples, and characterize these solutions to identify gaps for their further development. METHODS: During four human-centered design workshops composed of diverse expertise, participants ideated and clarified potential solutions to diagnostic disparities and were supported by environmental literature scan inputs. Nineteen individual semi-structured interviews with workshop participants validated identified solution examples and solution type characterizations, refining the typology. RESULTS: Our typology organizes 21 various types of potential diagnostic disparities solutions into four primary expertise categories needed for implementation: healthcare systems' internal expertise, educator-, multidisciplinary patient safety researcher-, and health IT-expertise. We provide descriptions of potential solution types ideated as focused on disparities and compare those to existing examples. Six types were characterized as having diagnostic-disparity-focused examples, five as having diagnostic-focused examples, and 10 as only having general healthcare examples. Only three solution types had widespread implementation. Twelve had implementation on limited scope, and six were mostly hypothetical. We describe gaps that inform the progress needed for each of the suggested solution types to specifically address diagnostic disparities and be suitable for the implementation in routine practice. CONCLUSIONS: Numerous opportunities exist to tailor existing solutions and promote their implementation. Likely enablers include new perspectives, more evidence, multidisciplinary collaborations, system redesign, meaningful patient engagement, and action-oriented coalitions.

Depressive and Anxiety Symptoms Were More Common for Transgender Individuals Whose Gender-Affirming Surgeries Were Cancelled or Delayed Due to COVID-19: A Global Cross-Sectional Study.

Gender-affirming surgeries, which have well-established mental health benefits, were cancelled and delayed for transgender people worldwide during the COVID-19 crisis. Of 253 scheduled gender-affirming surgeries among transgender adults across 35 countries in late 2020, 27% (n=69) reported that the COVID-19 crisis limited their access to gender-affirming surgery (i.e., cancelled, postponed indefinitely, or rescheduled). In adjusted models, respondents with reduced access to surgeries were somewhat more likely to screen positive for depressive or anxiety symptoms, whereas those who maintained access were more likely to report higher levels of happiness. Our findings illustrate the transgender-specific harms of the COVID-19 crisis on gender-affirming surgeries and mental health.

"It's probably an STI because you're gay": a qualitative study of diagnostic error experiences in sexual and gender minority individuals.

BACKGROUND: There is a critical need to identify specific causes of and tailored solutions to diagnostic error in sexual and gender minority (SGM) populations. PURPOSE: To identify challenges to diagnosis in SGM adults, understand the impacts of patient-reported diagnostic errors on patients' lives and elicit solutions. METHODS: Qualitative study using in-depth semistructured interviews. Participants were recruited using convenience and snowball sampling. Recruitment efforts targeted 22 SGM-focused organisations, academic centres and clinics across the USA. Participants were encouraged to share study details with personal contacts. Interviews were analysed using codebook thematic analysis. RESULTS: Interviewees (n=20) ranged from 20 to 60 years of age with diverse mental and physical health symptoms. All participants identified as sexual minorities, gender minorities or both. Thematic analysis revealed challenges to diagnosis. Provider-level challenges included pathologisation of SGM identity; dismissal of symptoms due to anti-SGM bias; communication failures due to providers being distracted by SGM identity and enforcement of cis-heteronormative assumptions. Patient-level challenges included internalised shame and stigma. Intersectional challenges included biases around factors like race and age. Patient-reported diagnostic error led to worsening relationships with providers, worsened mental and physical health and increased self-advocacy and community-activism. Solutions to reduce diagnostic disparities included SGM-specific medical education and provider training, using inclusive language, asking questions, avoiding assumptions, encouraging diagnostic coproduction, upholding high care standards and ethics, involving SGM individuals in healthcare improvement and increasing research on SGM health. CONCLUSIONS: Anti-SGM bias, queerphobia, lack of provider training and heteronormative attitudes hinder diagnostic decision-making and communication. As a result, SGM patients report significant harms. Solutions to mitigate diagnostic disparities require an intersectional approach that considers patients' gender identity, sexual orientation, race, age, economic status and system-level changes.

Patient and care partner assessments of diagnostic excellence in the emergency department: A cognitive interview study.

Background: Diagnostic excellence encompasses both receiving an accurate and timely explanation of a health problem that was communicated well, and the process it took to get to the correct diagnosis. Directly eliciting patients' perceptions of their diagnostic experience and outcomes after emergency visits is a promising method of assessing diagnostic excellence. However, little is known about how patients interpret and respond to questions about their diagnostic experiences and outcomes. Objective: To analyze patient and care partners' interpretation of questions capturing patient-reported diagnostic excellence in emergency settings. Design: Cognitive interviews using think-aloud and probing methods. Settings: Interviews were conducted virtually and via phone calls. Participants were patients or care partners of patients recently discharged from three emergency departments within a single academic health system in the Mid-Atlantic region of the US. Participants: 15 patients and care partners, 18 years or older, with recent emergency department experiences. Methods: Qualitative analysis using a deductive approach was used to code transcripts and analyze participant responses to Patient-Report to Improve Diagnostic Excellence in Emergency Department (PRIME-ED) questionnaire items. Themes of patient and care partners' questionnaire interpretations are presented descriptively. Results: 80% of participants were female, 47% were between the ages of 18-24 years, 47% of participants were White, and 7% were Hispanic/Latino. Participants shared their interpretations of diagnostic excellence following PRIME-ED domains: diagnostic accuracy and care team skills, their comprehension of the diagnosis, provider communication of uncertainty, and quality of diagnostic communication, including whether they felt the care team communicated well, adapted communication to their needs, listened and took concerns seriously, treated them as an equal, and provided clear, sufficient, and functional communication about follow-up steps. Responses indicated that patients and care partners can identify diagnostic errors, rationalize why their diagnosis was inaccurate, and assess whether diagnostic excellence was achieved. Respondents identified factors that contributed to their assessments of diagnostic accuracy and the quality of diagnostic communication. The quality of diagnostic communication contributed to patient perception of diagnostic accuracy and understanding of the diagnosis. Conclusions: Patient report is a useful tool for assessing diagnostic excellence in emergency settings. Our patient and care partners describe how they assess diagnostic excellence in the emergency department.Registration: N/A.Tweetable abstract: Patients and care partners provide accessible and useful information to assess diagnostic practices and diagnostic excellence in emergency departments.

Biofilm Formation and Structure in the Filamentous Fungus Fusarium graminearum, a Plant Pathogen.

Biofilms are protective structures for pathogens of plants and animals, in which cells are shielded from host defense responses and antimicrobial treatments. Although biofilms are well studied in bacterial pathogens, their development and structure in filamentous fungi, as well as their role in pathogenicity, are poorly understood. We show that the economically important plant pathogen Fusarium graminearum, a filamentous fungus, forms biofilms in vitro, which adhere to polystyrene, a hydrophobic surface. The biofilms have complex hyphal structures surrounded by a polymeric matrix that consists primarily of polysaccharides and extracellular nucleic acids, and lack lipids. Pellicles are formed in liquid cultures, floating biofilm masses that are common in bacterial biofilms, and noted but undescribed in filamentous fungal biofilms. Commonly, F. graminearum grows as hyphal colonies; however, on media which lack electron acceptors, an altered morphology is formed with predominantly short, bulbous hyphae embedded in the matrix. Supplementation of the biofilm-inducing medium with an electron acceptor restores the filamentous hyphal morphology, demonstrating that the formation of bulbous hyphae is due, at least in part, to oxidative stress. Plant hosts infected with pathogens generally respond by producing reactive oxygen species, commonly produced as a defense response. Thus, the formation of biofilms strongly suggests a role in protecting cells from host responses during the course of plant disease. IMPORTANCE Fusarium graminearum is a filamentous fungal pathogen that causes Fusarium head blight (FHB) in cereal crops, leading to devastating crop losses. We have demonstrated the ability of this pathogen to form biofilms. Biofilms are likely to be important in the disease cycle of F. graminearum and other plant pathogens, protecting cells from plant defenses and environmental conditions. Towards this end, we have characterized the formation of biofilms in F. graminearum in vitro, which, together with ongoing characterization of their association with host plants, provides a basis for understanding the functionality of biofilms in the pathogen disease cycle.

Human centered design workshops as a meta-solution to diagnostic disparities.

OBJECTIVES: Diagnostic errors - inaccurate or untimely diagnoses or failures to communicate diagnoses - are harmful and costly for patients and health systems. Diagnostic disparities occur when diagnostic errors are experienced at disproportionate rates by certain patient subgroups based, for example, on patients' age, sex/gender, or race/ethnicity. We aimed to develop and test the feasibility of a human centered design workshop series that engages diverse stakeholders to develop solutions for mitigating diagnostic disparities. METHODS: We employed a series of human centered design workshops supplemented by semi-structured interviews and literature evidence scans. Co-creation sessions and rapid prototyping by patient, clinician, and researcher stakeholders were used to generate design challenges, solution concepts, and prototypes. RESULTS: A series of four workshops attended by 25 unique participants was convened in 2019-2021. Workshops generated eight design challenges, envisioned 29 solutions, and formulated principles for developing solutions in an equitable, patient-centered manner. Workshops further resulted in the conceptualization of 37 solutions for addressing diagnostic disparities and prototypes for two of the solutions. Participants agreed that the workshop processes were replicable and could be implemented in other settings to allow stakeholders to generate context-specific solutions. CONCLUSIONS: The incorporation of human centered design through a series of workshops promises to be a productive way of engaging patient-researcher stakeholders to mitigate and prevent further exacerbation of diagnostic disparities. Healthcare stakeholders can apply human centered design principles to guide thinking about improving diagnostic performance and to center diverse patients' needs and experiences when implementing quality and safety improvements.

Spatial analysis of biomineralization associated gene expression from the mantle organ of the pearl oyster Pinctada maxima.

BACKGROUND: Biomineralization is a process encompassing all mineral containing tissues produced within an organism. One of the most dynamic examples of this process is the formation of the mollusk shell, comprising a variety of crystal phases and microstructures. The organic component incorporated within the shell is said to dictate this architecture. However general understanding of how this process is achieved remains ambiguous. The mantle is a conserved organ involved in shell formation throughout molluscs. Specifically the mantle is thought to be responsible for secreting the protein component of the shell. This study employs molecular approaches to determine the spatial expression of genes within the mantle tissue to further the elucidation of the shell biomineralization. RESULTS: A microarray platform was custom generated (PmaxArray 1.0) from the pearl oyster Pinctada maxima. PmaxArray 1.0 consists of 4992 expressed sequence tags (ESTs) originating from mantle tissue. This microarray was used to analyze the spatial expression of ESTs throughout the mantle organ. The mantle was dissected into five discrete regions and analyzed for differential gene expression with PmaxArray 1.0. Over 2000 ESTs were determined to be differentially expressed among the tissue sections, identifying five major expression regions. In situ hybridization validated and further localized the expression for a subset of these ESTs. Comparative sequence similarity analysis of these ESTs revealed a number of the transcripts were novel while others showed significant sequence similarities to previously characterized shell related genes. CONCLUSIONS: This investigation has mapped the spatial distribution for over 2000 ESTs present on PmaxArray 1.0 with reference to specific locations of the mantle. Expression profile clusters have indicated at least five unique functioning zones in the mantle. Three of these zones are likely involved in shell related activities including formation of nacre, periostracum and calcitic prismatic microstructure. A number of novel and known transcripts have been identified from these clusters. The development of PmaxArray 1.0, and the spatial map of its ESTs expression in the mantle has begun characterizing the molecular mechanisms linking the organics and inorganics of the molluscan shell.

Mechanical properties of silk of the Australian golden orb weavers Nephila pilipes and Nephilaplumipes.

Silks from orb-weaving spiders are exceptionally tough, producing a model polymer for biomimetic fibre development. The mechanical properties of naturally spun silk threads from two species of Australian orb-weavers, Nephila pilipes and Nephilaplumipes, were examined here in relation to overall thread diameter, the size and number of fibres within threads, and spider size. N. pilipes, the larger of the two species, had significantly tougher silk with higher strain capacity than its smaller congener, producing threads with average toughness of 150 MJ m-3, despite thread diameter, mean fibre diameter and number of fibres per thread not differing significantly between the two species. Within N. pilipes, smaller silk fibres were produced by larger spiders, yielding tougher threads. In contrast, while spider size was correlated with thread diameter in N. plumipes, there were no clear patterns relating to silk toughness, which suggests that the differences in properties between the silk of the two species arise through differing molecular structure. Our results support previous studies that found that the mechanical properties of silk differ between distantly related spider species, and extends on that work to show that the mechanical and physical properties of silk from more closely related species can also differ remarkably.

Quantifying kinematic differences between land and water during squats, split squats, and single-leg squats in a healthy population.

Aquatic exercises can be used in clinical and sporting disciplines for both rehabilitation and sports training. However, there is limited knowledge on the influence of water immersion on the kinematics of exercises commonly used in rehabilitation and fitness programs. The aim of this study was to use inertial sensors to quantify differences in kinematics and movement variability of bodyweight squats, split squats, and single-leg squats performed on dry land and whilst immersed to the level of the greater trochanter. During two separate testing sessions, 25 active healthy university students (22.3±2.9 yr.) performed ten repetitions of each exercise, whilst tri-axial inertial sensors (100 Hz) recorded their trunk and lower body kinematics. Repeated-measures statistics tested for differences in segment orientation and speed, movement variability, and waveform patterns between environments, while coefficient of variance was used to assess differences in movement variability. Between-environment differences in segment orientation and speed were portrayed by plotting the mean difference ±95% confidence intervals (CI) throughout the tasks. The results showed that the depth of the squat and split squat were unaffected by the changed environment while water immersion allowed for a deeper single leg squat. The different environments had significant effects on the sagittal plane orientations and speeds for all segments. Water immersion increased the degree of movement variability of the segments in all exercises, except for the shank in the frontal plane, which showed more variability on land. Without compromising movement depth, the aquatic environment induces more upright trunk and shank postures during squats and split squats. The aquatic environment allows for increased squat depth during the single-leg squat, and increased shank motions in the frontal plane. Our observations therefore support the use of water-based squat tasks for rehabilitation as they appear to improve the technique without compromising movement depth.

Limb symmetry during double-leg squats and single-leg squats on land and in water in adults with long-standing unilateral anterior knee pain; a cross sectional study.

BACKGROUND: The presence of pain during movement typically results in changes in technique. However, the physical properties of water, such as flotation, means that water-based exercise may not only reduce compensatory movement patterns but also allow pain sufferers to complete exercises that they are unable to perform on land. The purpose of this study was to assess bilateral kinematics during double-leg squats and single-leg squats on land and in water in individuals with unilateral anterior knee pain. A secondary aim was to quantify bilateral asymmetry in both environments in affected and unaffected individuals using a symmetry index. METHODS: Twenty individuals with unilateral knee pain and twenty healthy, matched controls performed body weight double- and single-leg squats in both environments while inertial sensors (100 Hz) recorded trunk and lower body kinematics. Repeated-measures statistics tested for environmental effects on movement depths and peak angles within the anterior knee pain group. Differences in their inter-limb symmetry in each environments was compared to the control group using analysis of variance tests. RESULTS: Water immersion allowed for greater movement depths during both exercises (double-leg squat: +7 cm, p = 0.032, single-leg squat: +9 cm, p = 0.002) for the knee pain group. The double-leg squat was symmetrical on land but water immersion revealed asymmetries in the lower body frontal plane movements. The single-leg squat revealed decreased hip flexion and frontal plane shank motions on the affected limb in both environments. Water immersion also affected the degree of lower limb asymmetry in both groups, with differences also showing between groups. CONCLUSIONS: Individuals with anterior knee pain achieved increased squat depth during both exercises whilst in water. Kinematic differences between the affected and unaffected limbs were often increased in water. Individuals with unilateral anterior knee pain appear to utilise different kinematics in the affected and unaffected limb in both environments.

Exposure assessment of diesel bus emissions.

The goal of this study was to measure ultrafine particle concentrations with diameters less than 1 mum emitted by diesel buses and to assess resulting human exposure levels. The study was conducted at the Woolloongabba Busway station in Brisbane, Australia in the winter months of 2002 during which temperature inversions frequently occurred. Most buses that utilize the station are fuelled by diesel, the exhaust of which contains a significant quantity of particle matter. Passengers waiting at the station are exposed to these particles emitted from the buses. During the course of this study, passenger census was conducted, based on video surveillance, yielding person-by-person waiting time data. Furthermore, a bus census revealed accurate information about the total number of diesel versus Compressed Natural Gas (CNG) powered buses. Background (outside of the bus station) and platform measurements of ultrafine particulate number size distributions were made to determine ambient aerosol concentrations. Particle number exposure concentration ranges from 10 and 40 to 60% of bus related exhaust fumes. This changes dramatically when considering the particle mass exposure concentration, where most passengers are exposed to about 50 to 80% of exhaust fumes. The obtained data can be very significant for comparison with similar work of this type because it is shown in previous studies that exhaust emissions causes cancer in laboratory animals. It was assumed that significant differences between platform and background distributions were due to bus emissions which, combined with passenger waiting times, yielded an estimate of passenger exposure to ultrafine particles from diesel buses. From an exposure point of view, the Busway station analyzed resembles a street canyon. Although the detected exhaust particle concentration at the outbound platform is found to be in the picogram range, exposure increases with the time passengers spend on the platform along with their breathing frequency.

Pacing during an ultramarathon running event in hilly terrain.

PURPOSE: The dynamics of speed selection as a function of distance, or pacing, are used in recreational, competitive, and scientific research situations as an indirect measure of the psycho-physiological status of an individual. The purpose of this study was to determine pacing on level, uphill and downhill sections of participants in a long (>80 km) ultramarathon performed on trails in hilly terrain. METHODS: Fifteen ultramarathon runners competed in a  173 km event (five finished at  103 km) carrying a Global-Positioning System (GPS) device. Using the GPS data, we determined the speed, relative to average total speed, in level (LEV), uphill (UH) and downhill (DH) gradient categories as a function of total distance, as well as the correlation between overall performance and speed variability, speed loss, and total time stopped. RESULTS: There were no significant differences in normality, variances or means in the relative speed in 173-km and 103-km participants. Relative speed decreased in LEV, UH and DH. The main component of speed loss occurred between 5% and 50% of the event distance in LEV, and between 5% and 95% in UH and DH. There were no significant correlations between overall performance and speed loss, the variability of speed, or total time stopped. CONCLUSIONS: Positive pacing was observed at all gradients, with the main component of speed loss occurring earlier (mixed pacing) in LEV compared to UH and DH. A speed reserve (increased speed in the last section) was observed in LEV and UH. The decrease in speed and variability of speed were more important in LEV and DH than in UH. The absence of a significant correlation between overall performance and descriptors of pacing is novel and indicates that pacing in ultramarathons in trails and hilly terrain differs to other types of running events.

Transcriptome Analysis of the Sydney Rock Oyster, Saccostrea glomerata: Insights into Molluscan Immunity.

BACKGROUND: Oysters have important ecological functions in their natural environment, acting as global carbon sinks and improving water quality by removing excess nutrients from the water column. During their life-time oysters are exposed to a variety of pathogens that can cause severe mortality in a range of oyster species. Environmental stressors encountered in their habitat can increase the susceptibility of oysters to these pathogens and in general have been shown to impact on oyster immunity, making immune parameters expressed in these marine animals an important research topic. RESULTS: Paired-end Illumina high throughput sequencing of six S. glomerata tissues exposed to different environmental stressors resulted in a total of 484,121,702 paired-end reads. When reads and assembled transcripts were compared to the C. gigas genome, an overall low level of similarity at the nucleotide level, but a relatively high similarity at the protein level was observed. Examination of the tissue expression pattern showed that some transcripts coding for cathepsins, heat shock proteins and antioxidant proteins were exclusively expressed in the haemolymph of S. glomerata, suggesting a role in innate immunity. Furthermore, analysis of the S. glomerata ORFs showed a wide range of genes potentially involved in innate immunity, from pattern recognition receptors, components of the Toll-like signalling and apoptosis pathways to a complex antioxidant defence mechanism. CONCLUSIONS: This is the first large scale RNA-Seq study carried out in S. glomerata, showing the complex network of innate immune components that exist in this species. The results confirmed that many of the innate immune system components observed in mammals are also conserved in oysters; however, some, such as the TLR adaptors MAL, TRIF and TRAM are either missing or have been modified significantly. The components identified in this study could help explain the oysters' natural resilience against pathogenic microorganisms encountered in their natural environment.

Host tree influences on longicorn beetle (Coleoptera: Cerambycidae) attack in subtropical Corymbia (Myrtales: Myrtaceae).

Phoracantha longicorn beetles are endemic to Australia, and some species have become significant pests of eucalypts worldwide, yet little is known about their host plant interactions and factors influencing tree susceptibility in Australia. Here, we investigate the host relationships of Phoracantha solida (Blackburn, 1894) on four eucalypt taxa (one pure species and three hybrid families), examining feeding site physical characteristics including phloem thickness, density, and moisture content, and host tree factors such as diameter, height, growth, taper, and survival. We also determine the cardinal and vertical (within-tree) and horizontal (between-tree) spatial distribution of borers. Fewer than 10% of P. solida attacks were recorded from the pure species (Corymbia citriodora subsp. variegate (Hook)), and this taxon also showed the highest survival, phloem thickness, relative growth rate, and bark:wood area. For the two most susceptible taxa, borer severity was negatively correlated with moisture content, and positively related to phloem density. Borers were nonrandomly and nonuniformly distributed within trees, and were statistically aggregated in 32% of plots. More attacks were situated on the northern side of the tree than the other aspects, and most larvae fed within the lower 50 cm of the bole, with attack height positively correlated with severity. Trees with borers had more dead neighbors, and more bored neighbors, than trees without borers, while within plots, borer incidence and severity were positively correlated. Because the more susceptible taxa overlapped with less susceptible taxa for several physical tree factors, the role of primary and secondary chemistries in determining host suitability needs to be investigated. Nevertheless, taxon, moisture content, phloem density, tree size, and mortality of neighboring trees appeared the most important physical characteristics influencing host suitability for P. solida at this site.

The contribution of energy systems during the upper body Wingate anaerobic test.

The purpose of this study was to measure the contribution of the aerobic, anaerobic lactic, and alactic systems during an upper body Wingate Anaerobic test (WAnT). Oxygen uptake and blood lactate were measured before, during, and after the WAnT and body composition analyzed by dual-energy X-ray absorptiometry. The contribution of the energy systems was 11.4% ± 1.4%, 60.3% ± 5.6%, and 28.3% ± 4.9% for the aerobic, anaerobic lactic, and alactic systems, respectively.