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Evidence accumulation models (EAMs) have become the dominant theoretical framework for rapid decision-making, and while many theoretically distinct variants exist, comparisons have proved challenging due to strong mimicry in their predictions about choice response time data. One solution to reduce mimicry is constraining these models with double responses, which are a second response that is made after the initial response. However, instructing participants that they are allowed to change their mind could influence their strategy for initial responding, meaning that explicit double responding paradigms may not generalise to standard paradigms. Here, we provide a validation of explicit double responding paradigms, by assessing whether participants' initial decisions – as measured by diffusion model parameters – differ based on whether or not they were instructed that they could change their response after their initial response. Across three experiments, our results consistently indicate that allowing for changes of mind does not influence initial responses, with Bayesian analyses providing at least moderate evidence in favour of the null in all cases. Our findings suggest that explicit double responding paradigms should generalise to standard paradigms, validating the use of explicit double responding in future rapid decision-making studies. [ABSTRACT FROM AUTHOR]

Proteostasis ensures the proper synthesis, folding, and trafficking of proteins and is required for cellular and organellar homeostasis. This network also oversees protein quality control within the cell and prevents accumulation of aberrant proteins, which can lead to cellular dysfunction and disease. For example, protein aggregates irreversibly disrupt proteostasis and can exert gain-of-function toxic effects. Although this process has been examined in detail for cytosolic proteins, how endoplasmic reticulum (ER)-tethered, aggregation-prone proteins are handled is ill-defined. To determine how a membrane protein with a cytoplasmic aggregation-prone domain is routed for ER-associated degradation (ERAD), we analyzed a new model substrate, TM-Ubc9ts. In yeast, we previously showed that TM-Ubc9ts ERAD requires Hsp104, which is absent in higher cells. In transient and stable HEK293 cells, we now report that TM-Ubc9ts degradation is largely proteasome-dependent, especially at elevated temperatures. In contrast to yeast, clipped TM-Ubc9ts polypeptides, which are stabilized upon proteasome inhibition, accumulate and are insoluble at elevated temperatures. TM-Ubc9ts cleavage is independent of the intramembrane protease RHBDL4, which clips other classes of ERAD substrates. These studies highlight an unappreciated mechanism underlying the degradation of aggregation-prone substrates in the ER and invite further work on other proteases that contribute to ERAD. [ABSTRACT FROM AUTHOR]

Music interventions in medicine have been shown to reduce anxiety and depression, decrease pain, and improve quality of life; however, a review of clinical music interventions in dermatology is lacking. Studies have shown that playing music for patients undergoing dermatologic procedures (Mohs surgery and anesthetic injections) can decrease pain and anxiety. Patients with pruritic conditions—such as psoriasis, neurodermatitis, atopic dermatitis, contact eczema, and situations requiring hemodialysis—have exhibited decreased levels of disease burden and pain when listening to preferred music, pre-chosen music, and live music. Studies suggest that listening to certain types of music may also alter serum cytokines, affecting the allergic wheal response. Additional research is necessary to determine the full potential and practical applications for clinical music interventions in dermatology. Future research should focus on targeting skin conditions that may benefit from the psychological, inflammatory, and immune effects of music. [ABSTRACT FROM AUTHOR]

Field researchers often use categorical systems to record primary preloading motivations, while survey researchers use continuous systems to examine preloading motivation ratings. We tested the psychometric properties of the two systems for measuring preloading motivations. Six hundred and eight-one undergraduate students and social media recruited participants (178 males; 503 females) completed an online survey pertaining to their last preloading experience. We measured preloading motivations by the categorical and continuous systems, general drinking motivations, estimations of preloaded standard drinks and harm. Measurements of preloading motivations by categorical (primary motivation) and continuous systems (motivation ratings) were concordant. The continuous system of preloading motivations held mix concurrence with general drinking motivations, implying conceptual differences between the two constructs. 'Enhancement-based' preloading motivations had strong relationships with estimations of preloaded standard drinks, while general drinking motivations for 'coping' were strong correlates of harm. Preloading motivations can be measured through either categorical or continuous systems. Implications for future psychometric measurement development is discussed. [ABSTRACT FROM AUTHOR]

Introduction: Screw cut out and varus collapse are the most common complication of locked plate fixation of proximal humerus fractures. The purpose of this study was to compare dual plating and endosteal fibular allograft struts as augmentation strategies to prevent varus collapse. Materials and methods: A trapezoidal osteotomy was created at the metaphysis to create a 2-part proximal humerus model in 18 paired shoulder specimens. Each specimen was assigned to group A, B, or C and was fixed with either a lateral locking plate, a lateral locking plate and anterior one-third tubular plate in an orthogonal 90/90 configuration, or a lateral locking plate with intramedullary fibular strut, respectively. The specimens were stressed in axial compression to failure. Displacement, elastic limit, ultimate load, and stiffness were recorded and calculated. Results: There was no difference in mean cyclic displacement between the three groups (0.71 mm vs 0.89 mm vs 0.61 mm for Group A, B, C, respectively). Lateral plating demonstrated the greatest absolute and relative displacement at the elastic limit (5.3 mm ± 1.5 and 4.4 mm ± 1.3) without significance. The elastic limit or yield point was greatest for fibular allograft, Group C (1223 N ± 501 vs 1048 N ± 367 for Group B and 951 N ± 249 for Group A) without significance. Conclusions: Dual plating of proximal humerus fractures in a 90–90 configuration demonstrates similar biomechanical properties as endosteal fibular strut allograft. Both strategies demonstrate superior stiffness to isolated lateral locked plating. [ABSTRACT FROM AUTHOR]

Greenhouse gas (GHG) accounting of emissions from land use, land-use change, and forestry necessarily involves consideration of landscape fire. This is of particular importance for Australia given that natural and human fire is a common occurrence, and many ecosystems are adapted to fire, and require periodic burning for plant regeneration and ecological health. Landscape fire takes many forms, can be started by humans or by lightning, and can be managed or uncontrolled. We briefly review the underlying logic of greenhouse gas accounting involving landscape fire in the 2020 Australian Government GHG inventory report. The treatment of wildfire that Australia chooses to enact under the internationally agreed guidelines is based on two core assumptions (a) that effects of natural and anthropogenic fire in Australian vegetation carbon stocks are transient and they return to the pre-fire level relatively quickly, and (b) that historically and geographically anomalous wildfires in forests should be excluded from national anthropogenic emission estimates because they are beyond human control. It is now widely accepted that anthropogenic climate change is contributing to increased frequency and severity of forest fires in Australia, therefore challenging assumptions about the human agency in fire-related GHG emissions and carbon balance. Currently, the national inventory focuses on forest fires; we suggest national greenhouse gas accounting needs to provide a more detailed reporting of vegetation fires including: (a) more detailed mapping of fire severity patterns; (b) more comprehensive emission factors; (c) better growth and recovery models from different vegetation types; (d) improved understanding how fires of different severities affect carbon stocks; and (e) improved analysis of the human agency behind the causes of emissions, including ignition types and fire-weather conditions. This more comprehensive accounting of carbon emissions would provide greater incentives to improve fire management practices that reduce the frequency, severity, and extent of uncontrolled landscape fires. [ABSTRACT FROM AUTHOR]

Key message: Novel sources of genetic resistance to tan spot in Australia have been discovered using one-step GWAS and genomic prediction models that accounts for additive and non-additive genetic variation. Tan spot is a foliar disease in wheat caused by the fungal pathogen Pyrenophora tritici-repentis (Ptr) and has been reported to generate up to 50% yield losses under favourable disease conditions. Although farming management practices are available to reduce disease, the most economically sustainable approach is establishing genetic resistance through plant breeding. To further understand the genetic basis for disease resistance, we conducted a phenotypic and genetic analysis study using an international diversity panel of 192 wheat lines from the Maize and Wheat Improvement Centre (CIMMYT), the International Centre for Agriculture in the Dry Areas (ICARDA) and Australian (AUS) wheat research programmes. The panel was evaluated using Australian Ptr isolates in 12 experiments conducted in three Australian locations over two years, with assessment for tan spot symptoms at various plant development stages. Phenotypic modelling indicated high heritability for nearly all tan spot traits with ICARDA lines displaying the greatest average resistance. We then conducted a one-step whole-genome analysis of each trait using a high-density SNP array, revealing a large number of highly significant QTL exhibiting a distinct lack of repeatability across the traits. To better summarise the genetic resistance of the lines, a one-step genomic prediction of each tan spot trait was conducted by combining the additive and non-additive predicted genetic effects of the lines. This revealed multiple CIMMYT lines with broad genetic resistance across the developmental stages of the plant which can be utilised in Australian wheat breeding programmes to improve tan spot disease resistance. [ABSTRACT FROM AUTHOR]

A central reason to worry that managers should not use nudges to influence employees is that doing so fails to treat employees as rational and/or autonomous (RA). Recent nudge defenders have marshaled a powerful line of response against this worry: in general, nudges treat us as the kind of RA agents we are, because nudges are apt to enhance our limited capacities for RA agency by improving our decision-making environments. Applied to managerial nudges, this would mean that when managers nudge their employees, they generally bolster their employees' limited RA agency and, thus, treat employees as the kinds of RA agents they are. My aim is to vindicate a qualified version of the initial worry from the nudge-defender response and, as a result, provide a clearer, more plausible framework for evaluating managerial nudges than what nudge critics have previously given. I do this, first, by showing how nudge defenders rely on equivocation between two different senses of "treating someone as RA." The value-preserving notion that supports the nudge-defender prescription to protect and enhance RA capacities is different from the authority-recognizing notion that underwrites the initial worry about nudging. Second, I argue that the authority-recognizing notion of treating someone as RA implies that managerial nudges treat employees as RA just when the nudges are compatible with relating to employees as equals. Third, I explain how, to determine when managerial nudges are compatible with relating to employees as equals, we need to consider how employees surrender aspects of their equal, agency-grounded authority to managers. [ABSTRACT FROM AUTHOR]

Purposely introduced in 1879, Pacific coast Striped Bass Morone saxatilis once supported a commercial fishery and currently supports a recreational fishery in the San Francisco Estuary Watershed, CA, USA; however, the population has been in decline for decades. Since little is known about sub-adult behavior on the Pacific coast, we used acoustic telemetry to investigate seasonal movement patterns and habitat use across three regions (bay, delta, and river) and the effects of temperature and salinity on habitat use over a 2-year period. Sub-adult movement and habitat use differed by year and age. In spring, age-I and age-II sub-adults moved within the delta (60%), river (20%), and bay (20%) regions, and by summer, some individuals moved to the bay (36%), while others remained in the delta (42%) and river (22%). Fall and winter showed equal movement between the bay and delta regions. During year 2, age-II and age-III fish inhabited the bay region across all seasons with the exception of spring when a few individuals migrated up river. Generally, sub-adults did not inhabit the river region in fall or winter. Sub-adults were not detected in water temperatures < 10 °C and occurred most often in 20–25 °C. Younger sub-adults inhabited limnetic habitat where older fish inhabited mesohaline and polyhaline habitats. Our findings suggest that sub-adult seasonal movement patterns and habitat use hotspots have important fishery management implications and can be useful to address concerns over how this non-native fish's predation impacts native and endangered fishes. [ABSTRACT FROM AUTHOR]

Savanna fire management is a topic of global debate, with early dry season burning promoted as a large-scale emissions reduction opportunity. To date, discussions have centred on carbon abatement efficacy, biodiversity and cultural benefits and/or risks. Here we use a case study of Darwin, Australia to highlight smoke pollution as another critical consideration. Smoke pollution from savanna fires is a major public health issue, yet absent so far from discussions of program design. Here, we assess the likely impacts of increased early dry season burning on smoke pollution in Darwin between 2004 and 2019, spanning the introduction and expansion of carbon abatement programs. We found increased smoke pollution in the early dry season but little change in the late dry season, contributing to a net annual increase in air quality standard exceedances. Geospatial analysis suggests this relates to increased burning in the path of early dry season trade winds. This study highlights the complex health trade-offs involved with any large-scale prescribed burning, including for carbon abatement. [ABSTRACT FROM AUTHOR]

Colonialism has disrupted Indigenous socioecological systems around the globe, including those supported by intentional landscape burning. Because most disruptions happened centuries ago, our understanding of Indigenous fire management is largely inferential and open to debate. Here, we investigate the ecological consequences of the loss of traditional Aboriginal fire management on fire-exposed savannas on the Arnhem Plateau, northern Australia, using the fire-sensitive conifer Callitris intratropica as a bio-indicator. We contrast Kakadu National Park, where traditional Aboriginal fire management was severely disrupted during the early twentieth century following Aboriginal relocation to surrounding settlements, and an adjacent Aboriginal estate where traditional Aboriginal fire management endures. Since 2006, traditional Aboriginal fire management at this site has been overlaid by a program of broad-scale institutionalized burning in the early dry season, designed to reduce greenhouse emissions. Using remote sensing, field survey, and dendrochronology, we show that on the Aboriginal estate, C. intratropica populations depend on the creation of a shifting patch mosaic of long unburned areas necessary for the recruitment of C. intratropica. However, the imposition of broad-scale fire management is disrupting this population patch dynamic. In Kakadu, there have been extreme declines of C. intratropica associated with widespread fires since the mid twentieth century and consequent proliferation of grass fuels. Fire management in Kakadu since 2007, designed to increase the size and abundance of patches of unburned vegetation, has not been able to reverse the population collapse of C. intratropica. Our study demonstrates that colonial processes including relocation of Indigenous people and institutional fire management can have deleterious consequences that are nearly irreversible because of hysteresis in C. intratropica population dynamics. [ABSTRACT FROM AUTHOR]

Background: Uncontrolled wildfires in Australian temperate Eucalyptus forests produce significant smoke emissions, particularly carbon dioxide (CO2) and particulates. Emissions from fires in these ecosystems, however, have received less research attention than the fires in North American conifer forests or frequently burned Australian tropical savannas. Here, we use the 2013 Forcett–Dunalley fire that caused the first recorded pyrocumulonimbus event in Tasmania, to understand CO2 and particulate matter (PM2.5) emissions from a severe Eucalyptus forest fire. We investigate the spatial patterns of the two emissions using a fine scale mapping of vegetation and fire severity (50 m resolution), and utilising available emission factors suitable for Australian vegetation types. We compare the results with coarse-scale (28 km resolution) emissions estimates from Global Fire Emissions Database (GFED) to determine the reliability of the global model in emissions estimation. Results: The fine scale inventory yielded total CO2 emission of 1.125 ± 0.232 Tg and PM2.5 emission of 0.022 ± 0.006 Tg, representing a loss of 56 t CO2 ha−1 and 1 t PM2.5 ha−1. The CO2 emissions were comparable to GFED estimates, but GFED PM2.5 estimates were lower by a factor of three. This study highlights the reliability of GFED for CO2 but not PM2.5 for estimating emissions from Eucalyptus forest fires. Our fine scale and GFED estimates showed that the Forcett–Dunalley fire produced 30% of 2013 fire carbon emissions in Tasmania, and 26–36% of mean annual fire emissions for the State, representing a significant single source of emissions. Conclusions: Our analyses highlight the need for improved PM2.5 emission factors specific to Australian vegetation, and better characterisation of fuel loads, particularly coarse fuel loads, to quantify wildfire particulate and greenhouse gas emissions more accurately. Current Australian carbon accountancy approach of excluding large wildfires from final GHG accounts likely exaggerates Tasmania's claim to carbon neutrality; we therefore recommend that planned and unplanned emissions are included in the final national and state greenhouse gas accounting to international conventions. Advancing these issues is important given the trajectory of more frequent large fires driven by anthropogenic climate change. [ABSTRACT FROM AUTHOR]

Although circumstantial evidence supports enhanced Toll-like receptor 7 (TLR7) signalling as a mechanism of human systemic autoimmune disease1–7, evidence of lupus-causing TLR7 gene variants is lacking. Here we describe human systemic lupus erythematosus caused by a TLR7 gain-of-function variant. TLR7 is a sensor of viral RNA8,9 and binds to guanosine10–12. We identified a de novo, previously undescribed missense TLR7Y264H variant in a child with severe lupus and additional variants in other patients with lupus. The TLR7Y264H variant selectively increased sensing of guanosine and 2',3'-cGMP10–12, and was sufficient to cause lupus when introduced into mice. We show that enhanced TLR7 signalling drives aberrant survival of B cell receptor (BCR)-activated B cells, and in a cell-intrinsic manner, accumulation of CD11c+ age-associated B cells and germinal centre B cells. Follicular and extrafollicular helper T cells were also increased but these phenotypes were cell-extrinsic. Deficiency of MyD88 (an adaptor protein downstream of TLR7) rescued autoimmunity, aberrant B cell survival, and all cellular and serological phenotypes. Despite prominent spontaneous germinal-centre formation in Tlr7Y264H mice, autoimmunity was not ameliorated by germinal-centre deficiency, suggesting an extrafollicular origin of pathogenic B cells. We establish the importance of TLR7 and guanosine-containing self-ligands for human lupus pathogenesis, which paves the way for therapeutic TLR7 or MyD88 inhibition.The missense TLR7Y264H gain-of-function genetic variation causes systemic lupus erythematosus in humans and mice. [ABSTRACT FROM AUTHOR]

Purpose: Despite increasing interest in utilizing quadriceps tendon (QT) grafts in anterior cruciate ligament reconstruction (ACLR), data on the optimal quadriceps graft thickness are limited. The purpose of this study was to characterize the mechanical properties for the quadriceps tendon, comparing full-thickness (FT) QT grafts with and without bone to a partial-thickness (PT) QT graft, and comparing the three QT grafts to four-stranded semitendinosus (4-SST) and bone-patellar tendon-bone (BTB) grafts and one experimental graft, the two-stranded rectus femoris (RF). Methods: Forty-eight (n = 48) young cadaveric grafts (mean age 32 ± 6 years) were utilized for testing with N = 8 specimens in each of the following groups; (1) FT QT with bone, (2) FT QT without bone, (3) PT QT without bone, (4) BTB, (5) RF, and (6) 4-SST. Each specimen was harvested and rigidly fixed in custom clamps to a dynamic tensile testing machine for biomechanical evaluation. Graft ultimate load and stiffness were recorded. Independent groups one-factor ANOVAs and Tukey's pairwise comparisons were performed for statistical analyses. Results: FT QT with bone and 4-SST grafts demonstrated similar ultimate loads to BTB grafts (both n.s), whereas PT QT demonstrate statistically significantly lower ultimate loads to BTB grafts (n.s) and 4-SST grafts (n.s). Furthermore, no statistically significant differences were observed between the ultimate loads of FT QT vs. PT QT grafts without bone (n.s) or between FT QT with vs. without bone (n.s). FT QT grafts with bone did not demonstrate statistically significantly greater ultimate loads than PT QT grafts without bone (n.s). The RF graft demonstrated statistically significantly lower ultimate loads to BTB grafts (p < 0.005) and 4-SST grafts (p < 0.014). Conclusions: Full thickness QT grafts with bone had similar material properties to BTB and a 4-SST grafts, while Partial thickness QT graft without bone had significantly lower material properties than BTB and 4-SST, in a biomechanical setting. [ABSTRACT FROM AUTHOR]

Cryo-electron microscopy has become an essential tool to understand structure and function of biological samples. Especially for pathogens, such as disease-causing bacteria and viruses, insights gained by cryo-EM can aid in developing cures. However, due to the biosafety restrictions of pathogens, samples are often treated by chemical fixation to render the pathogen inert, affecting the ultrastructure of the sample. Alternatively, researchers use in vitro or ex vivo models, which are non-pathogenic but lack the complexity of the pathogen of interest. Here we show that ultraviolet-C (UVC) radiation applied at cryogenic temperatures can be used to eliminate or dramatically reduce the infectivity of Vibrio cholerae and the bacterial virus, the ICP1 bacteriophage. We show no discernable structural impact of this treatment of either sample using two cryo-EM methods: cryo-electron tomography followed by sub-tomogram averaging, and single particle analysis (SPA). Additionally, we applied the UVC irradiation to the protein apoferritin (ApoF), which is a widely used test sample for high-resolution SPA studies. The UVC-treated ApoF sample resulted in a 2.1 Å structure indistinguishable from an untreated published map. This research demonstrates that UVC treatment is an effective and inexpensive addition to the cryo-EM sample preparation toolbox. Depelteau et al. present a new method to inactivate cryo-EM samples from pathogenic organisms before imaging using ultraviolet-C radiation in cryogenic conditions. This method allows for the inexpensive preparation of cryo-EM samples with no discernable structural impact of the treatment. [ABSTRACT FROM AUTHOR]

Introduction: While telemedicine usage has increased due to the COVID-19 pandemic, there remains little consensus about how spine surgeons perceive virtual care. The purpose of this study was to explore international perspectives of spine providers on the challenges and benefits of telemedicine.Methods: Responses from 485 members of AO Spine were analyzed, covering provider perceptions of the challenges and benefits of telemedicine. All questions were optional, and blank responses were excluded from analysis.Results: The leading challenges reported by surgeons were decreased ability to perform physical examinations (38.6%), possible increased medicolegal exposure (19.3%), and lack of reimbursement parity compared to traditional visits (15.5%). Fewer than 9.0% of respondents experienced technological issues. On average, respondents agreed that telemedicine increases access to care for rural/long-distance patients, provides societal cost savings, and increases patient convenience. Responses were mixed about whether telemedicine leads to greater patient satisfaction. North Americans experienced the most challenges, but also thought telemedicine carried the most benefits, whereas Africans reported the fewest challenges and benefits. Age did not affect responses.Conclusion: Spine surgeons are supportive of the benefits of telemedicine, and only a small minority experienced technical issues. The decreased ability to perform the physical examination was the top challenge and remains a major obstacle to virtual care for spine surgeons around the world, although interestingly, 61.4% of providers did not acknowledge this to be a major challenge. Significant groundwork in optimizing remote physical examination maneuvers and achieving legal and reimbursement clarity is necessary for widespread implementation. [ABSTRACT FROM AUTHOR]

Purpose: To utilize data from a global spine surgeon survey to elucidate (1) overall confidence in the telemedicine evaluation and (2) determinants of provider confidence. Methods: Members of AO Spine International were sent a survey encompassing participant's experience with, perception of, and comparison of telemedicine to in-person visits. The survey was designed through a Delphi approach, with four rounds of question review by the multi-disciplinary authors. Data were stratified by provider age, experience, telemedicine platform, trust in telemedicine, and specialty. Results: Four hundred and eighty-five surgeons participated in the survey. The global effort included respondents from Africa (19.9%), Asia Pacific (19.7%), Europe (24.3%), North America (9.4%), and South America (26.6%). Providers felt that physical exam-based tasks (e.g., provocative testing, assessing neurologic deficits/myelopathy, etc.) were inferior to in-person exams, while communication-based aspects (e.g., history taking, imaging review, etc.) were equivalent. Participants who performed greater than 50 visits were more likely to believe telemedicine was at least equivalent to in-person visits in the ability to make an accurate diagnosis (OR 2.37, 95% C.I. 1.03–5.43). Compared to in-person encounters, video (versus phone only) visits were associated with increased confidence in the ability of telemedicine to formulate and communicate a treatment plan (OR 3.88, 95% C.I. 1.71–8.84). Conclusion: Spine surgeons are confident in the ability of telemedicine to communicate with patients, but are concerned about its capacity to accurately make physical exam-based diagnoses. Future research should concentrate on standardizing the remote examination and the development of appropriate use criteria in order to increase provider confidence in telemedicine technology. [ABSTRACT FROM AUTHOR]

Purpose: To utilize a global survey to elucidate spine surgeons' perspectives towards research and resident education within telemedicine. Methods: A cross-sectional, anonymous email survey was circulated to the members of AO Spine, an international organization consisting of spine surgeons from around the world. Questions were selected and revised using a Delphi approach. A major portion of the final survey queried participants on experiences with telemedicine in training, the utility of telemedicine for research, and the efficacy of telemedicine as a teaching tool. Responses were compared by region. Results: A total of 485 surgeons completed the survey between May 15, 2020 and May 31, 2020. Though most work regularly with trainees (83.3%) and 81.8% agreed that telemedicine should be incorporated into clinical education, 61.7% of respondents stated that trainees are not present during telemedicine visits. With regards to the types of clinical education that telemedicine could provide, only 33.9% of respondents agreed that interpretation of physical exam maneuvers can be taught (mean score = − 0.28, SD = ± 1.13). The most frequent research tasks performed over telehealth were follow-up of imaging (28.7%) and study group meetings (26.6%). Of all survey responses provided by members, there were no regional differences (p > 0.05 for all comparisons). Conclusions: Our study of spine surgeons worldwide noted high agreement among specialists for the implantation of telemedicine in trainee curricula, underscoring the global acceptance of this medium for patient management going forward. A greater emphasis towards trainee participation as well as establishing best practices in telemedicine are essential to equip future spine specialists with the necessary skills for navigating this emerging platform. [ABSTRACT FROM AUTHOR]

Aims/hypothesis: In individuals with type 1 diabetes, chronic hyperglycaemia impairs aerobic fitness. However, the effect of acute marked hyperglycaemia on aerobic fitness is unclear, and the impact of insulin level has not been examined. In this study, we explored if acute hyperglycaemia with higher or low insulin levels affects V ̇ O 2 peak and other exercise performance indicators in individuals with type 1 diabetes. Methods: Eligible participants were aged 14 to 30 years, with complication-free, type 1 diabetes and HbA1c ≤ 75 mmol/mol (≤9%). Participants exercised in a clinical laboratory under three clamp (constant insulin, variable glucose infusion) conditions: euglycaemia (5 mmol/l) with 20 mU [m2 BSA]−1 min−1 insulin (where BSA is body surface area) (Eu20); hyperglycaemia (17 mmol/l) with 20 mU [m2 BSA]−1 min−1 insulin (Hyper20); and hyperglycaemia (17 mmol/l) with 5 mU [m2 BSA]−1 min−1 insulin (Hyper5) on separate days. Participants and the single testing assessor were blinded to condition, with participants allocated to randomised testing condition sequences as they were consecutively recruited. Standardised testing (in order) conducted on each of the three study days included: triplicate 6 second sprint cycling, grip strength, single leg static balance, vertical jump and modified Star Excursion Balance Test, ten simple and choice reaction times and one cycle ergometer V ̇ O 2 peak test. The difference between conditions in the aforementioned testing measures was analysed, with the primary outcome being the difference in V ̇ O 2 peak . Results: Twelve recreationally active individuals with type 1 diabetes (8 male, mean ± SD 17.9 ± 3.9 years, HbA1c 61 ± 11 mmol/mol [7.7 ± 1.0%], 7 ± 3 h exercise/week) were analysed. Compared with Eu20, V ̇ O 2 peak was lower in Hyper20 (difference 0.17 l/min [95% CI 0.31, 0.04; p = 0.02] 6.6% of mean Eu20 level), but Hyper5 was not different (p = 0.39). Compared with Eu20, sprint cycling peak power was not different in Hyper20 (p = 0.20), but was higher in Hyper5 (64 W [95% CI 13, 115; p = 0.02] 13.1%). Hyper20 reaction times were not different (simple: p = 0.12) but Hyper5 reaction times were slower (simple: 11 milliseconds [95% CI 1, 22; p = 0.04] 4.7%) than Eu20. No differences between Eu20 and either hyperglycaemic condition were observed for the other testing measures (p > 0.05). Conclusions/interpretation: Acute marked hyperglycaemia in the higher but not low insulin state impaired V ̇ O 2 peak but to a small extent. Acute hyperglycaemia had an insulin-dependent effect on sprint cycling absolute power output and reaction time but with differing directionality (positive for sprint cycling and negative for reaction time) and no effect on the other indicators of exercise performance examined. We find that acute hyperglycaemia is not consistently adverse and does not impair overall exercise performance to an extent clinically relevant for recreationally active individuals with type 1 diabetes. Funding: This research was funded by Diabetes Research Western Australia and Australasian Paediatric Endocrine Group grants. [ABSTRACT FROM AUTHOR]

How complex, multi-component macromolecular machines evolved remains poorly understood. Here we reveal the evolutionary origins of the chemosensory machinery that controls flagellar motility in Escherichia coli. We first identify ancestral forms still present in Vibrio cholerae, Pseudomonas aeruginosa, Shewanella oneidensis and Methylomicrobium alcaliphilum, characterizing their structures by electron cryotomography and finding evidence that they function in a stress response pathway. Using bioinformatics, we trace the evolution of the system through γ-Proteobacteria, pinpointing key evolutionary events that led to the machine now seen in E. coli. Our results suggest that two ancient chemosensory systems with different inputs and outputs (F6 and F7) existed contemporaneously, with one (F7) ultimately taking over the inputs and outputs of the other (F6), which was subsequently lost. Bacterial chemosensory systems are grouped into 17 flagellar classes (F1-17). Here the authors employ electron cryotomography and comparative genomics to characterise the chemosensory arrays in γ-proteobacteria and identify a structural distinct form of F7 that was repurposed to a different biological role over the course of its evolution. [ABSTRACT FROM AUTHOR]

The Interior Exploration using Seismic Investigations, Geodesy and Heat Transport (InSight) spacecraft landed successfully on Mars and imaged the surface to characterize the surficial geology. Here we report on the geology and subsurface structure of the landing site to aid in situ geophysical investigations. InSight landed in a degraded impact crater in Elysium Planitia on a smooth sandy, granule- and pebble-rich surface with few rocks. Superposed impact craters are common and eolian bedforms are sparse. During landing, pulsed retrorockets modified the surface to reveal a near surface stratigraphy of surficial dust, over thin unconsolidated sand, underlain by a variable thickness duricrust, with poorly sorted, unconsolidated sand with rocks beneath. Impact, eolian, and mass wasting processes have dominantly modified the surface. Surface observations are consistent with expectations made from remote sensing data prior to landing indicating a surface composed of an impact-fragmented regolith overlying basaltic lava flows. The InSight spacecraft landed on Mars on November 2018. Here, the authors characterize the surficial geology of the landing site and compare with observations and models derived from remote sensing data prior to landing and from ongoing in situ geophysical investigations of the subsurface. [ABSTRACT FROM AUTHOR]

Smoke exposure from landscape and coal mine fires can have severe impacts on human health. The ability of health studies to accurately identify potential associations between smoke exposure and health is dependent on the techniques utilised to quantify exposure concentrations for the population at risk. The evolution of spatial modelling techniques capable of better characterising this association has potential to provide more precise health effect estimates. We reviewed the literature to identify and assess the spatial modelling techniques available to estimate smoke PM2.5 or PM10 concentrations from open biomass or coal mine fires. Four electronic databases were searched: MEDLINE, EMBASE, Scopus and Web of Science. Studies were included if they utilised any method for modelling the spatial distribution of PM2.5 or PM10 concentrations from open biomass or coal mine fires and had applied the modelled PM to health data. Studies based on un-adjusted monitoring data, or which were not in English, were excluded. We identified 28 studies which utilised five spatial modelling techniques to assess exposure from open biomass fires: dispersion models, land use regression, satellite remote sensing, spatial interpolation and blended models. No studies of coal mine fires were identified. We found the most effective models combined multiple techniques to enhance the strengths and mitigate the weaknesses of the underlying individual techniques. "Blended" models have the potential to facilitate research in regions currently under represented in biomass or coal mine fire studies as well as enhancing the power of studies to identify associations with health outcomes. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study was to compare the reliability and accuracy of existing computed tomography (CT) methods for measuring the distal tibiofibular syndesmosis in uninjured, paired cadaveric specimens and in simulated malreduction models. It was hypothesized that a repeatable set of measurements exists to accurately and quantitatively describe the typical forms of syndesmotic malreduction using contralateral ankle comparison.Methods: Twelve cadaveric lower-leg specimen pairs were imaged with CT to generate models for this study. Thirty-five measurements were performed on each native model. Next, four distinct fibular malreductions were produced via digital simulation and all measurements were repeated for each state: (1) 2-mm lateral translation; (2) 2-mm posterior translation; (3) 7-degree external rotation; (4) the previous three states combined. The modified standardized response mean (mSRM) was calculated for each measurement. To assess rater reliability and side-to-side agreements of the native state measurements, intraclass correlation coefficients (ICC) and Pearson correlation coefficients (PCC) were calculated, respectively.Results: The most responsive measurements for detecting isolated malreduction were the Leporjärvi clear space for lateral translation, the Nault anterior tibiofibular distance for posterior translation, and the Nault talar dome angle for external rotation of the fibula. These measurements demonstrated fair to excellent inter-rater ICCs (0.64-0.76) and variable side-to-side PCCs (0.14-0.47).Conclusions: The most reliable method to assess the syndesmosis on CT was to compare side-to-side differences using three distinct measurements, one for each type of fibular malreduction, allowing assessment of the magnitude and directionality of syndesmosis malreduction. Reliable evaluation is essential for assessing subtle syndesmosis injuries, malreduction and surgical planning. [ABSTRACT FROM AUTHOR]

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In January 2017, hundreds of fires in Mediterranean Chile burnt more than 5000 km2, an area nearly 14 times the 40-year mean. We contextualize these fires in terms of estimates of global fire intensity using MODIS satellite record, and provide an overview of the climatic factors and recent changes in land use that led to the active fire season and estimate the impact of fire emissions to human health. The primary fire activity in late January coincided with extreme fire weather conditions including all-time (1979-2017) daily records for the Fire Weather Index (FWI) and maximum temperature, producing some of the most energetically intense fire events on Earth in the last 15-years. Fire activity was further enabled by a warm moist growing season in 2016 that interrupted an intense drought that started in 2010. The land cover in this region had been extensively modified, with less than 20% of the original native vegetation remaining, and extensive plantations of highly flammable exotic Pinus and Eucalyptus species established since the 1970s. These plantations were disproportionally burnt (44% of the burned area) in 2017, and associated with the highest fire severities, as part of an increasing trend of fire extent in plantations over the past three decades. Smoke from the fires exposed over 9.5 million people to increased concentrations of particulate air pollution, causing an estimated 76 premature deaths and 209 additional admissions to hospital for respiratory and cardiovascular conditions. This study highlights that Mediterranean biogeographic regions with expansive Pinus and Eucalyptus plantations and associated rural depopulation are vulnerable to intense wildfires with wide ranging social, economic, and environmental impacts, which are likely to become more frequent due to longer and more extreme wildfire seasons. [ABSTRACT FROM AUTHOR]

To divide, Gram-negative bacterial cells must remodel cell wall at the division site. It remains debated, however, whether this cell wall remodeling alone can drive membrane constriction, or if a constrictive force from the tubulin homolog FtsZ is required. Previously, we constructed software (REMODELER 1) to simulate cell wall remodeling during growth. Here, we expanded this software to explore cell wall division (REMODELER 2). We found that simply organizing cell wall synthesis complexes at the midcell is not sufficient to cause invagination, even with the implementation of a make-before-break mechanism, in which new hoops of cell wall are made inside the existing hoops before bonds are cleaved. Division can occur, however, when a constrictive force brings the midcell into a compressed state before new hoops of relaxed cell wall are incorporated between existing hoops. Adding a make-beforebreak mechanism drives division with a smaller constrictive force sufficient to bring the midcell into a relaxed, but not necessarily compressed, state. [ABSTRACT FROM AUTHOR]

Purpose: This paper outlines a service evaluation of an exercise referral scheme for adults suffering from a variety of physical or mental health conditions or who were deemed are at risk of developing such conditions. The evaluation aimed to assess the impact of the scheme at increasing physical activity and at reducing BMI and waist circumference.Method: This was a retrospective evaluation looking at levels of physical activity and changes to anthropometric measures over a period of 6 months. Each participant self-reported their levels of physical activity for the previous 7 days at three time points: baseline (T1), at 12-week exit from the scheme (T2), and at 6-month follow-up (T3). Waist circumference and BMI were also recorded by either a health professional or self-reported at these time points.Results: Six hundred seventy participants were referred during the evaluation period, of whom 494 were eligible. Of those 494, 211 completed the 12-week scheme and 135 completed a 6-month follow-up. Significant increases in levels of physical activity were recorded between T1 and T2 and between T1 and T3. Furthermore, significant reductions in waist circumference were noted between T1 and T2 and between T1 and T3, and BMI significantly decreased between T1 and T2 but significantly increased between T2 and T3.Conclusion: The service has proven effective at increasing levels of physical activity among participants and has had a positive impact on waist circumference and body for clients who remain engaged with the programme. [ABSTRACT FROM AUTHOR]

Ocular neovascularization is a common pathological feature in diabetic retinopathy and neovascular age-related macular degeneration that can lead to severe vision loss. We evaluated the therapeutic efficacy of a novel endogenous inhibitor of angiogenesis, the calreticulin anti-angiogenic domain (CAD180), and its functional 112-residue fragment, CAD-like peptide 112 (CAD112), delivered using a self-complementary adeno-associated virus serotype 2 (scAAV2) in rodent models of oxygen-induced retinopathy and laser-induced choroidal neovascularization. The expression of CAD180 and CAD112 was elevated in human umbilical vein endothelial cells transduced with scAAV2-CAD180 or scAAV2-CAD112, respectively, and both inhibited angiogenic activity in vitro. Intravitreal gene delivery of scAAV2-CAD180 or scAAV2-CAD112 significantly inhibited ischemia-induced retinal neovascularization in rat eyes (CAD180: 52.7% reduction; CAD112: 49.2% reduction) compared to scAAV2-mCherry, as measured in retinal flatmounts stained with isolectin B4. Moreover, the retinal structure and function were unaffected by scAAV2-CAD180 or scAAV2-CAD112, as measured by optical coherence tomography and electroretinography. Moreover, subretinal delivery of scAAV2-CAD180 or scAAV2-CAD112 significantly attenuated laser-induced choroidal neovascularization in mouse eyes compared to scAAV2-mCherry, as measured by fundus fluorescein angiography (CAD180: 62.4% reduction; CAD112: 57.5% reduction) and choroidal flatmounts (CAD180: 40.21% reduction; CAD112: 43.03% reduction). Gene delivery using scAAV2-CAD180 or scAAV2-CAD112 has significant potential as a therapeutic option for the management of ocular neovascularization. [ABSTRACT FROM AUTHOR]

Scald, caused by Rhyncosporium commune, is a common foliar disease of barley in south eastern Australia, causing significant damage during cool, wet seasonal conditions. In this study, scald caused up to 30% (1.4 t/ha) grain yield loss, reduced grain plumpness and weight by up to 25% and 20% respectively and increased screenings by up to 6%. Seed, fertiliser and foliar applied fungicides reduced scald severity and provided improvements in both grain yield and quality. Dual foliar fungicide application of propiconazole at early stem elongation (Z31) and flag leaf emergence (Z39) was most effective in controlling scald and reducing grain yield and quality losses. The seed applied fungicide, fluxapyroxad was the most effective single application fungicide treatment. Varieties with host-plant resistance had less grain yield and quality loss than the very susceptible rated variety, however, these varied between seasons. This study demonstrated that an integrated disease management strategy is required for scald in barley that includes growing resistant varieties and timely fungicide applications. [ABSTRACT FROM AUTHOR]

Purpose: Long-term outcomes and the prevalence of osteoarthritis after surgical treatment of knee dislocations are lacking in the literature. The purpose of this study was to investigate the prevalence of knee osteoarthritis and knee function at a minimum of 10 years after knee dislocation surgery.Methods: Sixty-five patients surgically treated for knee dislocations at a single level I trauma center between May 1996 and December 2004 were evaluated at a minimum of 10 years. Patients were evaluated with radiographs for knee osteoarthritis using the Kellgren-Lawrence (KL) grading system, Tegner activity score, Lysholm score, IKDC-2000, KOOS, subjective stability on physical examination, KT-1000 arthrometer, and single-leg hop tests. Osteoarthritis was defined as KL grades 2 or greater.Results: The median follow-up time was 12.7 years (range 10.0-18.8 years), and the median age was 46.9 years (range 26.8-76.1 years). Radiographic osteoarthritis was present in 42% (23, 14, and 5% in KL grades II, III, and IV, respectively) of the patients in the operated knee compared to 6% in the uninjured knee. Knee function was generally improved with a median Tegner activity score of 4 (range 1-8), an average Lysholm score of 84 ± 17, and an average IKDC-2000 score of 73 ± 19.Conclusion: Twenty-seven patients (42%) developed OA 10 years after surgical treatment of knee dislocations. Patients reported improved knee function and minimal-to-moderate pain. Age at surgery was a predictor of development of OA, with more patients >30 years at the time of surgery developing OA. Meniscal and cartilage injuries at time of surgery were not associated with development of OA. Patients being treated for knee dislocation should be counselled about the increased long-term risk of post-traumatic OA.Level Of Evidence: III. [ABSTRACT FROM AUTHOR]

Purpose: To document the effectiveness of a novel technique to decrease tibial slope in patients who underwent a proximal opening-wedge osteotomy with an anteriorly sloped plate placed in a posteromedial position. The hypothesis was that posteromedial placement of an anteriorly sloped osteotomy plate with an adjunctive anterior bone staple on the tibia would decrease, and maintain, the tibial slope correction at a minimum of 6 months following the osteotomy.Methods: All patients who underwent biplanar medial opening-wedge proximal tibial osteotomy with anterior staple augmentation to decrease sagittal plane tibial slope were included, and data were collected prospectively and reviewed retrospectively. Indications for decreasing tibial slope included medial compartment osteoarthritis with at least one of the following: ACL deficiency, posterior meniscus deficiency, or flexion contracture. Preoperative, immediate postoperative, and 6-month postoperative radiographs were reviewed.Results: Twenty-one patients (14 males and 7 females) were included in the study with a mean age of 36.5 years. Intrarater and interrater reliability of slope measurements were excellent at all time points (ICC ≥ 0.94, ICC ≥ 0.85). The osteotomy resulted in an average tibial slope decrease of 0.8 from preoperative (n.s.). At 6-month postoperative, average slope was not significantly different from time-zero postoperative slope (mean = +0.2°).Conclusions: The most important finding of this study was that posteromedial placement of an anteriorly angled osteotomy plate augmented with an anterior staple during a biplanar medial opening-wedge proximal tibial osteotomy did not decrease sagittal plane tibial slope. Whether a staple was effective in maintaining tibial slope from time zero to 6 months postoperatively was unable to be assessed due to no significant change in tibial slope from the preoperative postoperative states. The results of this study note that current osteotomy plate designs and surgical techniques are not effective in decreasing sagittal plane tibial slope.Level Of Evidence: IV. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the outcomes of two commonly used transosseous-equivalent (TOE) arthroscopic rotator cuff repair (RCR) techniques for full-thickness supraspinatus tendon tears (FTST) using a robust multi-predictor model.Methods: 155 shoulders in 151 patients (109 men, 42 women; mean age 59 ± 10 years) who underwent arthroscopic RCR of FTST, using either a knotted suture bridging (KSB) or a knotless tape bridging (KTB) TOE technique were included. ASES and SF-12 PCS scores assessed at a minimum of 2 years postoperatively were modeled using propensity score weighting in a multiple linear regression model. Patients able to return to the study center underwent a follow-up MRI for evaluation of rotator cuff integrity.Results: The outcome data were available for 137 shoulders (88%; n = 35/41 KSB; n = 102/114 KTB). Seven patients (5.1%) that underwent revision rotator cuff surgery were considered failures. The median postoperative ASES score of the remaining 130 shoulders was 98 at a mean follow-up of 2.9 years (range 2.0-5.4 years). A higher preoperative baseline outcome score and a longer follow-up had a positive effect, whereas a previous RCR and workers' compensation claims (WCC) had a negative effect on final ASES or SF 12 PCS scores. The repair technique, age, gender and the number of anchors used for the RCR had no significant influence. Fifty-two patients returned for a follow-up MRI at a mean of 4.4 years postoperatively. Patients with a KSB RCR were significantly more likely to have an MRI-diagnosed full-thickness rotator cuff re-tear (p < 0.05).Conclusions: Excellent outcomes can be achieved at a minimum of 2 years following arthroscopic KSB or KTB TOE RCR of FTST. The preoperative baseline outcome score, a prior RCR, WCC and the length of follow-up significantly influenced the outcome scores. The repair technique did not affect the final functional outcomes, but patients with KTB TOE RCR were less likely to have a full-thickness rotator cuff re-tear.Level Of Evidence: Level III, Retrospective Comparative Study. [ABSTRACT FROM AUTHOR]

Purpose: Varus failure is one of the most common failure modes following surgical treatment of proximal humeral fractures. Straight antegrade nails (SAN) theoretically provide increased stability by anchoring to the densest zone of the proximal humerus (subchondral zone) with the end of the nail. The aim of this study was to biomechanically investigate the characteristics of this "proximal anchoring point" (PAP). We hypothesized that the PAP would improve stability compared to the same construct without the PAP.Methods: Straight antegrade humeral nailing was performed in 20 matched pairs of human cadaveric humeri for a simulated unstable two-part fracture.Results: Biomechanical testing, with stepwise increasing cyclic axial loading (50-N increments each 100 cycles) at an angle of 20° abduction revealed significantly higher median loads to failure for SAN constructs with the PAP (median, 450 N; range, 200-1.000 N) compared to those without the PAP (median, 325 N; range, 100-500 N; p = 0.009). SAN constructs with press-fit proximal extensions (endcaps) showed similar median loads to failure (median, 400 N; range, 200-650 N), when compared to the undersized, commercially available SAN endcaps (median, 450 N; range, 200-600 N; p = 0.240).Conclusions: The PAP provided significantly increased stability in SAN constructs compared to the same setup without this additional proximal anchoring point. Varus-displacing forces to the humeral head were superiorly reduced in this setting. This study provides biomechanical evidence for the "proximal anchoring point's" rationale. Straight antegrade humeral nailing may be beneficial for patients undergoing surgical treatment for unstable proximal humeral fractures to decrease secondary varus displacement and thus potentially reduce revision rates. [ABSTRACT FROM AUTHOR]

Purpose: Quantitative MRI T2 mapping is a non-invasive imaging technique sensitive to biochemical changes, but no studies have evaluated T2 mapping in pathologic rotator cuff tendons. It was sought to evaluate the efficacy of T2 mapping in detecting differences in the supraspinatus tendon (SST) among patients with tendinosis, partial tears and minimally retracted full-thickness tears, relative to asymptomatic volunteers.Methods: The pathologic cohort consisted of two arthroscopically verified groups: tendinosis and a tear group of partial tears or minimally retracted full-thickness tears, and was compared to an asymptomatic cohort with no prior history of shoulder pathology. The SST was manually segmented from the footprint to the medial humeral head in the coronal and sagittal planes and divided into six clinically relevant subregions. Mean T2 values and inter- and intra-rater reliability were assessed.Results: In the anterolateral subregion, the tear group exhibited significantly higher mean T2 values (43.9 ± 12.7 ms) than the tendinosis (34.9 ± 3.9 ms; p = 0.006) and asymptomatic (33.6 ± 5.3 ms; p = 0.015) groups. In the posterolateral subregion, the tear group had higher mean T2 values (45.2 ± 13.7) than the asymptomatic group (34.7 ± 6.7; p = 0.012). Inter- and intra-rater reliability was mostly excellent (ICC > 0.75).Conclusion: T2 mapping is an accurate non-invasive method to identify quantitatively early rotator cuff pathology. The lateral region in the coronal plane in particular may differentiate partial and small minimally retracted full-thickness tears from tendinosis and asymptomatic tendons. Understanding and being able to measure quantitatively the process of tendon degeneration and subsequent tearing may help clinicians to better predict at-risk groups and to stratify treatment options.Level Of Evidence: III. [ABSTRACT FROM AUTHOR]

Introduction: The use of total shoulder arthroplasty (TSA) to treat primary glenohumeral osteoarthritis (GHOA) is increasing. Factors influencing patient satisfaction after surgery have not been well documented. The aim of this study was to determine demographic, radiologic, and surgical, factors predictive for satisfaction after TSA for GHOA. Materials and Methods: Between 2005 and 2012, 95 shoulders undergoing TSA for GHOA by a single surgeon were eligible for inclusion in the study. Age, gender, previous surgeries, American Society of Anesthesiologists (ASA) score, and Walch glenoid morphology were analyzed as satisfaction predictors. Patients with Walch glenoid type C were excluded. Results: Data on 80/92(87 %) shoulders were available at a mean of 3 years (range 2-9). Three complications (3 %) and 2 failures (2 %) occurred. The outcome scores collected significantly improved from preoperative values (p < 0.05). Median patient satisfaction was 10/10. Gender, age, previous surgery, ASA score, and Walch morphology were not associated with patient satisfaction. Conclusions: TSA provided excellent results for patients with idiopathic GHOA with low complication and failure rates. Outcomes after TSA for type B glenoid morphology with posterior subluxation were similar to outcomes after TSA for centered type A morphology. Overall patient satisfaction was high and was not influenced by the demographic, anatomic, and surgical variables investigated. Level Of Evidence: III, Therapeutic study, Retrospective Cohort Study. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study was to investigate the effect of lateral meniscal posterior root avulsions combined with intact meniscofemoral ligaments (MFLs), deficient MFLs, anterior cruciate ligament (ACL) tears and reconstructions, and root repairs using an established tibiofemoral contact mechanics testing protocol.Methods: Ten fresh-frozen cadaveric knees were tested with six knee conditions (1: intact; 2: lateral meniscal posterior root avulsion; 3: root avulsion and deficient MFLs; 4: condition 3 with ACL tear; 5: condition 4 with ACL reconstruction; 6: ACL reconstruction with root repair) at five flexion angles (0°, 30°, 45°, 60°, and 90°), under a 1000-N axial load. Contact area and pressure were measured with Tekscan sensors.Results: Compared to the intact state, condition 2 did not significantly change lateral compartment contact area or pressure. Changes in contact mechanics were greater at increased flexion angles; for condition 3 at 0° and 90°, contact area decreased 37 and 52 % [95 % CI (21-53) and (39-66), respectively] and mean contact pressure increased 55 and 87 % [95 % CI (33-76) and (59-114), respectively]. Root repair with ACL reconstruction was not significantly different from the intact state.Conclusions: The MFLs protect the lateral compartment from changes in contact mechanics in the setting of a lateral meniscal posterior root avulsion, whereas a combination of lateral meniscal root avulsion and deficient MFLs leads to significant changes. Concurrent ACL reconstruction and lateral meniscal root repair restore mean contact pressure and area to the intact state and are recommended in this combined injury to prevent or slow the development of lateral compartment arthritis. [ABSTRACT FROM AUTHOR]