Gravitational waves from coalescing neutron stars encode information about nuclear matter at extreme densities, inaccessible by laboratory experiments. The late inspiral is influenced by the presence of tides, which depend on the neutron star equation of state. Neutron star mergers are expected to often produce rapidly rotating remnant neutron stars that emit gravitational waves. These will provide clues to the extremely hot post-merger environment. This signature of nuclear matter in gravitational waves contains most information in the 2–4 kHz frequency band, which is outside of the most sensitive band of current detectors. We present the design concept and science case for a Neutron Star Extreme Matter Observatory (NEMO): a gravitational-wave interferometer optimised to study nuclear physics with merging neutron stars. The concept uses high-circulating laser power, quantum squeezing, and a detector topology specifically designed to achieve the high-frequency sensitivity necessary to probe nuclear matter using gravitational waves. Above 1 kHz, the proposed strain sensitivity is comparable to full third-generation detectors at a fraction of the cost. Such sensitivity changes expected event rates for detection of post-merger remnants from approximately one per few decades with two A+ detectors to a few per year and potentially allow for the first gravitational-wave observations of supernovae, isolated neutron stars, and other exotica.

Through diversity of composition, sequence, and interfacial structure, hybrid materials greatly expand the palette of materials available to access novel functionality. The NSF Division of Materials Research recently supported a workshop (October 17–18, 2019) aiming to (1) identify fundamental questions and potential solutions common to multiple disciplines within the hybrid materials community; (2) initiate interfield collaborations between hybrid materials researchers; and (3) raise awareness in the wider community about experimental toolsets, simulation capabilities, and shared facilities that can accelerate this research. This article reports on the outcomes of the workshop as a basis for cross-community discussion. The interdisciplinary challenges and opportunities are presented, and followed with a discussion of current areas of progress in subdisciplines including hybrid synthesis, functional surfaces, and functional interfaces.

Large material accumulations from single events found in the archaeological record are frequently defined as evidence of ritual. They are interpreted as generalized deposit categories that imply rather than infer human motivations. While useful in the initial collection of data, these categories can, over time, become interpretations in and of themselves. The emic motivations behind the formation process of ‘ritual deposits’ ought to be considered using a relational ontology as an approach to understanding how past populations interacted with non-human actors, such as structures and natural features on the landscape. The present study evaluates the assembly and possible function of a dense deposit of artifacts recovered from a Classic period sweat bath at Xultun, Guatemala. Analyses of the various artifact types and human remains in the deposit in relation to what is known of the social history of the sweat bath itself illustrate ontological relationships among offered materials as well as between the offering and the personified place in which it was recovered. We observe that with a better understanding of place, it is possible to evaluate the ritual logic in Classic Maya material negotiations.

The Spoon-billed Sandpiper Calidris pygmaea is a ‘Critically Endangered’ migratory shorebird. The species faces an array of threats in its non-breeding range, making conservation intervention essential. However, conservation efforts are reliant on identifying the species’ key stopover and wintering sites. Using Maximum Entropy models, we predicted Spoon-billed Sandpiper distribution across the non-breeding range, using data from recent field surveys and satellite tracking. Model outputs suggest only a limited number of stopover sites are suitable for migrating birds, with sites in the Yellow Sea and on the Jiangsu coast in China highlighted as particularly important. All the previously known core wintering sites were identified by the model including the Ganges-Brahmaputra Delta, Nan Thar Island and the Gulf of Mottama. In addition, the model highlighted sites subsequently found to be occupied, and pinpointed potential new sites meriting investigation, notably on Borneo and Sulawesi, and in parts of India and the Philippines. A comparison between the areas identified as most likely to be occupied and protected areas showed that very few locations are covered by conservation designations. Known sites must be managed for conservation as a priority, and potential new sites should be surveyed as soon as is feasible to assess occupancy status. Site protection should take place in concert with conservation interventions including habitat management, discouraging hunting, and fostering alternative livelihoods.

OBJECTIVES/GOALS: Specific Aim 1 To examine sex distribution of psoas cross sectional area (CSA) on CT imaging in a cohort of trauma patients age 55 and older. We will use three methods of assessing psoas CSA: psoas CSA averaged between left and right, average psoas CSA adjusted for height, and average psoas CSA adjusted for body surface area (psoas index). Specific Aim 2 Use multivariable logistic regression prediction modeling to compare the 3 methods of CT psoas muscle measurement widely used in the literature in their ability to predict a composite of in-hospital morbidity and mortality in trauma patients ages 55 and older. METHODS/STUDY POPULATION: The Maine Medical Center Trauma Registry is maintained by the Trauma Surgery Service at Maine Medical Center in Portland, Maine, the only Level-1 trauma center in the state. After receiving approval from the Institutional Review Board of Maine Medical Center for this retrospective cohort study, we queried the Maine Medical Center Trauma Registry for all adults 55 years and older who underwent evaluation by the Trauma Service between January 1, 2015 and January 1, 2019. In the case of multiple admissions within the study time period, only a patient’s index admission was used. MaineHealth IMPACS imaging software was used to measure bilateral psoas CSA on each patient CT. The Maine Medical Center electronic medical record was queried for additional clinical information including the ICD codes associated with each patient encounter. Data analysis was performed using R statistical software (R project, Vienna, Austria). Data is reported as median + IQR for CSA measurements. The agreement between the three methods of quantifying psoas CSA was evaluated using Pearson correlation (R package “stats”). Inter-rater reliability of psoas muscle measurements was evaluated using intra-class correlation (R package “irr”). Prediction models for the composite outcome of in-hospital morbidity and mortality were constructed using multivariable logistic regression. Bootstrapping was used for internal validation and shrinkage to avoid overfitting. Models including psoas CSA were compared to a baseline model without psoas CSA to evaluated incremental added predictive ability. RESULTS/ANTICIPATED RESULTS: This cohort provides a basis for examining the population distribution of psoas CSA in adults 55 years and older. IN addition to a high level of agreement between the three methods of measuring psoas CSA (Spearman coefficient > 0.9), there was also high level of inter rater reliability in psoas muscle assessment (intraclass correlation 0.9). We anticipate that psoas CSA adjusted for body surface area will add the most incremental predictive ability to a model predicting in-hospital morbidity and mortality. DISCUSSION/SIGNIFICANCE OF IMPACT: Given the heterogeneity of health status amongst elderly trauma patients, a major challenge lies in the rapid objective identification of those elderly trauma patients who are frail. Due to the limitations in current frailty measures, there has been a surge of interest in surrogate markers of frailty, such as muscle mass, as predictive factors of poor outcomes after trauma.Several studies have found that sarcopenia is associated with post injury morbidity and mortality. Estimates of the prevalence of sarcopenia among trauma patients vary across studies due to differences in definition and sample characteristics. In order to appropriately categorize patients as sarcopenic, the population distribution of psoas CSA on CT must be established. The psoas measurement that best correlates with outcomes has yet to be determined, and it is unclear which measurement should be implemented in usual practice. Our main objective is to improve the outcomes of sarcopenic patients hospitalized with trauma by implementing in the future patient-centered interventions which will account for sarcopenia.

Introduction: Hyperkalemia is a common electrolyte disturbance associated with morbidity and mortality. Commonly used therapies for hyperkalemia include IV calcium, sodium bicarbonate, insulin, beta-adrenergic agents, ion-exchange resins, diuretics and hemodialysis. This study aims to evaluate which treatments are more commonly used to treat hyperkalemia and to examine factors which influence those clinical decisions. Methods: This is a retrospective chart review of all cases of hyperkalemia encountered in 2017 at a Canadian adult ED. Potassium values were classified as mild (5.5 - 6.5 mEq/L), moderate (>6.5 - 7.5 mEq/L) and severe (>7.5 mEq/L). Treatment choices were then recorded and matched to hemodynamic stability, degree of hyperkalemia and ECG findings. More statistical methods to test correlation between treatment and specific variables will be performed over the next 2 months, including logistic regression to highlight potential determinants of treatment and Chi-square tests to verify randomness and to construct 95% confidence intervals. Results: 1867 ED visits were identified, of which 479 met the inclusion criteria. 89.1% of hyperkalemia cases were mild, 8.2% were moderate, and 2.7% were severe. IV insulin was used in 22.1% of cases, followed by Kayexalate in 20.5%, sodium bicarbonate in 12.3%, IV calcium in 9.4%, frusemide in 7.3%, salbutamol in 2.7%, and dialysis in 1.9%. Moderate and severe hyperkalemia were associated with higher use of insulin (79.5% and 64.3% respectively), IV calcium (41% and 64.3% respectively), sodium bicarbonate (56.4% and 85.7% respectively). Bradycardia was associated with higher insulin and IV calcium use (46.7% and 33.3% respectively). Hypotension was associated with a similar increase in use of insulin and IV calcium (34.2% and 23.7% respectively). There were only 15 cases of cardiac arrest in which sodium bicarbonate and IV calcium were more frequently used (80% and 60% respectively). Conclusion: This study demonstrates variability in the ED management of hyperkalemia. We found that Insulin and Kayexalate were the 2 most common interventions, with degree of hyperkalemia, bradycardia and hypotension influencing rates of treatment. Overuse of kayexalate for emergent treatment of hyperkalemia is evident despite weak supporting evidence. Paradoxically, beta adrenergic agents were underutilized despite their rapid effect and safer profile. The development of a widely accepted guideline may help narrow the differences in practice and potentially improve outcomes.

Introduction: CAEP recently developed the acute atrial fibrillation (AF) and flutter (AFL) [AAFF] Best Practices Checklist to promote optimal care and guidance on cardioversion and rapid discharge of patients with AAFF. We sought to assess the impact of implementing the Checklist into large Canadian EDs. Methods: We conducted a pragmatic stepped-wedge cluster randomized trial in 11 large Canadian ED sites in five provinces, over 14 months. All hospitals started in the control period (usual care), and then crossed over to the intervention period in random sequence, one hospital per month. We enrolled consecutive, stable patients presenting with AAFF, where symptoms required ED management. Our intervention was informed by qualitative stakeholder interviews to identify perceived barriers and enablers for rapid discharge of AAFF patients. The many interventions included local champions, presentation of the Checklist to physicians in group sessions, an online training module, a smartphone app, and targeted audit and feedback. The primary outcome was length of stay in ED in minutes from time of arrival to time of disposition, and this was analyzed at the individual patient-level using linear mixed effects regression accounting for the stepped-wedge design. We estimated a sample size of 800 patients. Results: We enrolled 844 patients with none lost to follow-up. Those in the control (N = 316) and intervention periods (N = 528) were similar for all characteristics including mean age (61.2 vs 64.2 yrs), duration of AAFF (8.1 vs 7.7 hrs), AF (88.6% vs 82.9%), AFL (11.4% vs 17.1%), and mean initial heart rate (119.6 vs 119.9 bpm). Median lengths of stay for the control and intervention periods respectively were 413.0 vs. 354.0 minutes (P < 0.001). Comparing control to intervention, there was an increase in: use of antiarrhythmic drugs (37.4% vs 47.4%; P < 0.01), electrical cardioversion (45.1% vs 56.8%; P < 0.01), and discharge in sinus rhythm (75.3% vs. 86.7%; P < 0.001). There was a decrease in ED consultations to cardiology and medicine (49.7% vs 41.1%; P < 0.01), but a small but insignificant increase in anticoagulant prescriptions (39.6% vs 46.5%; P = 0.21). Conclusion: This multicenter implementation of the CAEP Best Practices Checklist led to a significant decrease in ED length of stay along with more ED cardioversions, fewer ED consultations, and more discharges in sinus rhythm. Widespread and rigorous adoption of the CAEP Checklist should lead to improved care of AAFF patients in all Canadian EDs.