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The Nonesuch Formation microbiota provide a window into ca. 1075 Ma life within the interior of ancient North America. The Nonesuch water body formed following the cessation of widespread volcanism within the Midcontinent Rift as the basin continued to subside. In northern Michigan and Wisconsin, USA, the Copper Harbor Conglomerate records terrestrial alluvial fan and fluvial plain environments that transitioned into subaqueous lacustrine deposition of the Nonesuch Formation. These units thin toward a paleotopographic high associated with the Brownstone Falls angular unconformity. Due to these “Brownstone Highlands,” we were able to explore the paleoenvironment laterally at different depths in contemporaneous deposits. Rock magnetic data constrain that when the lake was shallow, it was oxygenated as evidenced by an oxidized mineral assemblage. Oxygen levels were lower at greater depth—in the deepest portions of the water body, anoxic conditions are recorded. An intermediate facies in depth and redox between these endmembers preserves detrital magnetite and hematite, which can be present in high abundance due to the proximal volcanic highlands. This magnetic facies enabled the development of a paleomagnetic pole based on both detrital magnetite and hematite that constrains the paleolatitude of the lake to 7.1 ± 2.8°N. Sediments of the intermediate facies preserve exquisite organic-walled microfossils, with microfossils being less diverse to absent in the anoxic facies where amorphous organic matter is more likely to be preserved. The assemblage of cyanobacteria and eukaryotes (both photoautotrophs and heterotrophs) lived within the oxygenated waters of this tropical Mesoproterozoic water body.

Abstract Background Medical students may be influenced by perceived program culture and personal fit when applying to residency. Activity Medical students were given three iterations of a generic residency program description presented with gender-neutral, feminine, or masculine skewed language and were subsequently asked to assess their perception of gender diversity and fit within each program. Results Gendered language in program descriptions had a direct effect on all participants’ sense of gender diversity in programs. The feminine-skewed description was most favorably perceived, regardless of respondent gender. Conclusion These findings provide a starting point from which residency programs can consider the impact of gendered language on student recruitment and gender equity.

In many cultural contexts, judging another as conscious or not has profound practical, legal, and philosophical consequences. However, little research focuses on how our ability to make such judgements arises. Thirty years ago a classic set of studies by Flavell et al. demonstrated that children do not develop a complex understanding of conscious ideation in others until age 8. We investigated whether children understand a more basic aspect of conscious experience at earlier ages: a person has conscious thoughts when awake in contrast to when soundly, dreamlessly asleep. We tested 211 3-to-13-year-old children, who watched video sequences, focally one where a person was asleep and then awoke. Children were half as likely to say the target was having thoughts while asleep compared to awake. Even the youngest children made this distinction, demonstrating that children as young as 3-years have at least a basic understanding of consciousness in others.

Abstract Severe febrile illnesses in children encompass life-threatening organ dysfunction caused by diverse pathogens and other severe inflammatory syndromes. A comparative approach to these illnesses may identify shared and distinct features of host immune dysfunction amenable to immunomodulation. Here, using immunophenotyping with mass cytometry and cell stimulation experiments, we illustrate trajectories of immune dysfunction in 74 children with multi-system inflammatory syndrome in children (MIS-C) associated with SARS-CoV-2, 30 with bacterial infection, 16 with viral infection, 8 with Kawasaki disease, and 42 controls. We explore these findings in a secondary cohort of 500 children with these illnesses and 134 controls. We show that neutrophil activation and apoptosis are prominent in multi-system inflammatory syndrome, and that this is partially shared with bacterial infection. We show that memory T cells from patients with multi-system inflammatory syndrome and bacterial infection are exhausted. In contrast, we show viral infection to be characterized by a distinct signature of decreased interferon signaling and lower interferon receptor gene expression. Improved understanding of immune dysfunction may improve approaches to immunomodulator therapy in severe febrile illnesses in children.

Objective: The COVID-19 pandemic highlighted and exacerbated health inequities worldwide. While several studies have examined the impact of individual social factors on COVID infection, our objective was to examine how interactions of social factors were associated with the risk of testing positive for SARS-CoV-2 during the first two years of the pandemic. Study design and setting: We conducted an observational cohort study using linked health administrative data for Ontarians tested for SARS-CoV-2 between January 1st, 2020, and December 31st, 2021. We constructed multivariable models to examine the association between SARS-CoV-2 positivity and key variables including immigration status (immigrants vs. other Ontarians), and neighbourhood variables for household size, income, essential worker status, and visible minority status. We report main and interaction effects using odds ratios and predicted probabilities, with age and sex controlled in all models. Results: Of 6,575,523 Ontarians in the cohort, 88.5 % tested negative, and 11.5 % tested positive for SARS-CoV-2. In all models, immigrants and those living in neighbourhoods with large average household sizes had greater odds of testing positive for SARS-CoV-2. The strength of these associations increased with increasing levels of neighbourhood marginalization for income, essential worker proportion and visible minority proportion. We observed little change in the probability of testing positive across neighbourhood income quintiles among other Ontarians who live in neighbourhoods with smaller households, but a large change in probability among other Ontarians who live in neighbourhoods with larger households. Conclusion: Our study found that SARS-CoV-2 positivity was greater among people with certain combinations of social factors, but in all cases the probability of testing positive was consistently greater for immigrants than for other Ontarians. Examining interactions of social factors can provide a more nuanced and more comprehensive understanding of health inequity than examining factors separately.

Hinge constructs can be used in revision total knee arthroplasty in cases of major collateral ligament deficiency, global knee instability, repeated failure of constrained implants, or large bone defects. Although the success of this construct in revision total knee arthroplasty varies depending on the type of surgery and bone quality, hinged implants can solve a wide array of complex problems while preserving stable flexion-extension motion for ambulation. The most common reasons for re-revision include patellofemoral complications, aseptic loosening, and infection. Most cases of mechanical failure for these hinged constructs occur at the hinge component. Here, we report the first instance of catastrophic femoral component failure in a modular rotating hinge via a low-energy mechanism.

Meniscus tissue is commonly injured due to sports-related injuries and age-related degeneration and approximately 50% of individuals with a meniscus tear will develop post-traumatic osteoarthritis (PTOA). Given that the meniscus has limited healing potential, new therapeutic strategies are required to enhance meniscus repair. Porcine meniscus-derived matrix (MDM) scaffolds improve meniscus integrative repair, but sources of human meniscus tissue have not been investigated. Therefore, the objectives of this study were to generate healthy and osteoarthritic (OA) MDM scaffolds and to compare meniscus cellular responses and integrative repair. Meniscus cells showed high viability on both healthy and OA scaffolds. While DNA content was higher in cell-seeded OA scaffolds than cell-seeded healthy scaffolds, CCK-8, and both sGAG and collagen content were similar between scaffold types. After 28 days in an ex vivo meniscus defect model, healthy and OA scaffolds had similar DNA, sGAG, and collagen content. However, the shear strength of repair was reduced in defects containing OA scaffolds compared to healthy scaffolds. In conclusion, healthy human allograft tissue is a useful source for generating MDM scaffolds that can support cellular growth, ECM production, and ex vivo integrative repair of the meniscus, highlighting the potential suitability for tissue engineering approaches to improve meniscus repair.

The Academy of Management Journal (AMJ) provides a broad platform for empirical management research that encompasses diverse topics, methodologies, and data types. Despite the wide array of studies published, successful research projects share key elements, such as an intriguing research question, a structured theoretical foundation, and a suitable research setting. This From the Editors piece introduces the AMJ Management Research Canvas, a guide for scholars to systematically address these core elements. By helping researchers align their studies with essential design and theoretical criteria, the canvas aims to improve the quality and coherence of submissions, benefiting both novice and experienced scholars in management and organizational research.

Abstract Microglia are important players in surveillance and repair of the brain. Implanting an electrode into the cortex activates microglia, produces an inflammatory cascade, triggers the foreign body response, and opens the blood-brain barrier. These changes can impede intracortical brain-computer interfaces performance. Using two-photon imaging of implanted microelectrodes, we test the hypothesis that low-intensity pulsed ultrasound stimulation can reduce microglia-mediated neuroinflammation following the implantation of microelectrodes. In the first week of treatment, we found that low-intensity pulsed ultrasound stimulation increased microglia migration speed by 128%, enhanced microglia expansion area by 109%, and a reduction in microglial activation by 17%, indicating improved tissue healing and surveillance. Microglial coverage of the microelectrode was reduced by 50% and astrocytic scarring by 36% resulting in an increase in recording performance at chronic time. The data indicate that low-intensity pulsed ultrasound stimulation helps reduce the foreign body response around chronic intracortical microelectrodes.