Ice shelves affect the stability of ice sheets by supporting the mass balance of ice upstream of the grounding line. Marine ice, formed from supercooled water freezing at the base of ice shelves, contributes to mass gain and affects ice dynamics. Direct measurements of marine ice thickness are rare due to the challenges of borehole drilling. Here we assume hydrostatic equilibrium to estimate marine ice distribution beneath the Amery Ice Shelf (AIS) using meteoric ice-thickness data obtained from radio-echo sounding collected during the Chinese National Antarctic Research Expedition between 2015 and 2019. This is the first mapping of marine ice beneath the AIS in nearly 20 years. Our new estimates of marine ice along two longitudinal bands beneath the northwest AIS are spatially consistent with earlier work but thicker. We also find a marine ice layer exceeding 30 m of thickness in the central ice shelf and patchy refreezing downstream of the grounding line. Thickness differences from prior results may indicate time-variation in basal melting and freezing patterns driven by polynya activity and coastal water intrusions masses under the ice shelf, highlighting that those changes in ice–ocean interaction are impacting ice-shelf stability.

Objectives/Goals: Imaging neuromas, benign tumors of nerve tissue, can be difficult in amputees with osseointegrated (OI) prostheses, in which a metal rod is implanted into the residual limb. Magnetic resonance imaging can be inadequate due to the implanted metal. The aim of this study is to assess the use of ultrasound to detect neuromas in patients with OI prostheses. Methods/Study Population: This is a single-institutional observational study of 7 patients undergoing lower limb OI prostheses. Lower extremity nerve ultrasounds with 2-D grayscale and Doppler were completed at postoperative follow-up visits following OI prosthesis implantation. Specifically, the sciatic nerve, tibial nerve, common peroneal nerve, and sural nerve were targeted for imaging. Neuromas found on ultrasound were measured by maximal length in three planes. Results/Anticipated Results: Our study to date includes two patients with OI prostheses. The remaining patients will be accrued by the end of December. The first patient with a left below-the-knee amputation completed imaging 3 years after OI prosthesis implantation. The common peroneal nerve showed preserved fascicular architecture and morphology, with no distinct neuroma formation. However, the sural nerve demonstrated a 6 × 5 × 4 mm neuroma with minimal pain with deep palpation. The tibial nerve demonstrated a 14 × 11 × 8 mm neuroma within the medial calf musculature, with mild pain with deep palpation. The second patient with a right above-the-knee amputation was imaged 10 months after OI prosthesis implantation. The sciatic nerve demonstrated preserved fascicular morphology and terminated in a smooth taper. There was no defined neuroma. Discussion/Significance of Impact: In conclusion, we have preliminarily shown in the first two patients that ultrasound can successfully image neuromas in patients with OI prostheses in the postoperative period. Furthermore, despite a patient that was 3 years postoperative with two neuromas, the neuromas produced minimal to mild pain with targeted palpation.

Exclusion of evidence when its probative value is exceeded by its risk of creating unfair prejudice has long been a fundamental safeguard against unfair trials and wrongful convictions. In 2016, IMM v The Queen (IMM) curtailed that safeguard by holding that trial judges should assess probative value on the assumption that the evidence is reliable and credible. The IMM majority placed emphasis on the capacity of the evidence. In doing so, it provided a mysterious qualification: some evidence may lack probative value not because it is unreliable, but because it is ‘simply unconvincing’. The majority illustrated unconvincingness with the example of an unreliable eyewitness identification. Courts and legal scholars criticised the majority judgment for its harmful implications and for its apparent incoherence. From a review of almost 4 years of post-IMM jurisprudence and deeper exploration into one particular case, we find that ‘simply unconvincing’ has accentuated the confusion and inconsistency in Australian evidence jurisprudence.

For a member of Congress to be a successful lawmaker, they must work collaboratively with their colleagues. Previous work has found that interpersonal relationships among lawmakers are a key predictor of legislative collaboration—particularly among members from opposing parties. In the wake of the events of January 6, 2021, many Democratic lawmakers claimed that their relationships with some of their Republican colleagues were irretrievably broken and they would be unable to continue collaborating with members who voted against certifying electoral votes from the 2020 presidential election. Using data on original cosponsorship and legislative effectiveness from the 115th to 117th Congresses (2017–22) we find that Republican lawmakers who voted against the certification of electoral votes lost bipartisan collaborators and saw a drastic decrease in their legislative effectiveness in the 117th Congress.

Autobiographical memories show a temporal pattern with relatively many events recalled from the recent past (recency) and from adolescence to early adulthood (reminiscence bump), and very few events recalled from the first few years of life (childhood amnesia). The current study examined a temporal pattern for external memory – information stored outside of one's brain. Three survey studies asked participants to choose which age(s) in their life they would most want to keep photos from, supposing they had many photos from every year. Participants chose 1 year of photos in Study 1, which sampled undergraduates (N = 499, median age = 19), and in Study 2, which sampled online participants using stratified age brackets (N = 252, age range 18–82). Participants chose 3 years of photos in Study 3, which sampled online participants over 40 using stratified age brackets (N = 240, age range 40–93). Participants’ choices largely showed preferences for time periods likely to be well remembered (recency and the reminiscence bump). Qualitative coding of participants’ reasons for their choices showed common themes, such as positive emotions, connections to other people and pets, life milestones, personal growth, and school. Results suggest that in the case of photos, external memory served to mostly enhance or enrich internal memory and less often to compensate for internal memory.

Emergency departments are high-risk settings for severe acute respiratory coronavirus virus 2 (SARS-CoV-2) surface contamination. Environmental surface samples were obtained in rooms with patients suspected of having COVID-19 who did or did not undergo aerosol-generating procedures (AGPs). SARS-CoV-2 RNA surface contamination was most frequent in rooms occupied by coronavirus disease 2019 (COVID-19) patients who received no AGPs.

OBJECTIVES/GOALS: Using the covariate-rich Veteran Health Administration data, estimate the association between Proton Pump Inhibitor (PPI) use and severe COVID-19, rigorously adjusting for confounding using propensity score (PS)-weighting. METHODS/STUDY POPULATION: We assembled a national retrospective cohort of United States veterans who tested positive for SARS-CoV-2, with information on 33 covariates including comorbidity diagnoses, lab values, and medications. Current outpatient PPI use was compared to non-use (two or more fills and pills on hand at admission vs no PPI prescription fill in prior year). The primary composite outcome was mechanical ventilation use or death within 60 days; the secondary composite outcome included ICU admission. PS-weighting mimicked a 1:1 matching cohort, allowing inclusion of all patients while achieving good covariate balance. The weighted cohort was analyzed using logistic regression. RESULTS/ANTICIPATED RESULTS: Our analytic cohort included 97,674 veterans with SARS-CoV-2 testing, of whom 14,958 (15.3%) tested positive (6,262 [41.9%] current PPI-users, 8,696 [58.1%] non-users). After weighting, all covariates were well-balanced with standardized mean differences less than a threshold of 0.1. Prior to PS-weighting (no covariate adjustment), we observed higher odds of the primary (9.3% vs 7.5%; OR 1.27, 95% CI 1.13-1.43) and secondary (25.8% vs 21.4%; OR 1.27, 95% CI 1.18-1.37) outcomes among PPI users vs non-users. After PS-weighting, PPI use vs non-use was not associated with the primary (8.2% vs 8.0%; OR 1.03, 95% CI 0.91-1.16) or secondary (23.4% vs 22.9%;OR 1.03, 95% CI 0.95-1.12) outcomes. DISCUSSION/SIGNIFICANCE: The associations between PPI use and severe COVID-19 outcomes that have been previously reported may be due to limitations in the covariates available for adjustment. With respect to COVID-19, our robust PS-weighted analysis provides patients and providers with further evidence for PPI safety.

Whiteite-(MnMnMn), Mn2+Mn2+Mn2+2Al2(PO4)4(OH)2⋅8H2O, is a new whiteite-subgroup member of the jahnsite group from the Foote Lithium Company mine, Kings Mountain district, Cleveland County, North Carolina, USA. It was found in small vugs of partially oxidised pegmatite minerals on the East dump of the mine, in association with eosphorite, hureaulite, fairfieldite, mangangordonite, whiteite-(CaMnMn) and jasonsmithite. It occurs as sugary aggregates of blade-like crystals up to 0.1 mm long and as epitaxial overgrowths on whiteite-(CaMnMn). The crystals are colourless to very pale brown, with a vitreous lustre and a white streak. The blades are flattened on {001} and elongated along [010], with poor cleavage on {001}. The calculated density is 2.82 g⋅cm–3. Optically it is biaxial (–) with α = 1.599(2), β = 1.605(2), γ = 1.609(2) (white light); 2V (calc.) = 78.2°, having no observable dispersion or pleochroism, and with orientation X = b. Electron microprobe analyses and structure refinement gave the empirical formula (Mn2+0.59Ca0.38Na0.03)Σ1.00Mn1.00(Mn2+1.04Fe3+0.58Fe2+0.23Zn0.16Mg0.08)Σ2.09Al2.04(PO4)3.89(OH)3.18(H2O)7.26. Whiteite-(MnMnMn) is monoclinic, P2/a, a = 15.024(3) Å, b = 6.9470(14) Å, c = 9.999(2) Å, β = 110.71(3)°, V = 976.2(4) Å3 and Z = 2. The crystal structure was refined using synchrotron single-crystal data to wRobs = 0.057 for 2014 reflections with I > 3σ(I). Site occupancy refinements confirm the ordering of dominant Mn in the X, M1 and M2 sites of the general jahnsite-group formula XM1(M2)2(M3)2(H2O)8(OH)2(PO4)4. A review of published crystallochemical data for jahnsite-group minerals shows a consistent chemical pressure effect in these minerals, manifested as a contraction of the unit-cell parameter, a, as the mean size of the X and M1 site cations increases. This is analogous to negative thermal expansion, but with increasing cation size, rather than heating, inducing octahedral rotations that result in an anisotropic contraction of the unit cell.

This paper describes a computational investigation of multimode instability growth and multimaterial mixing induced by multiple shock waves in a high-energy-density (HED) environment, where pressures exceed 1 Mbar. The simulations are based on a series of experiments performed at the National Ignition Facility (NIF) and designed as an HED analogue of non-HED shock-tube studies of the Richtmyer–Meshkov instability and turbulent mixing. A three-dimensional computational modelling framework is presented. It treats many complications absent from canonical non-HED shock-tube flows, including distinct ion and free-electron internal energies, non-ideal equations of state, radiation transport and plasma-state mass diffusivities, viscosities and thermal conductivities. The simulations are tuned to the available NIF data, and traditional statistical quantities of turbulence are analysed. Integrated measures of turbulent kinetic energy and enstrophy both increase by over an order of magnitude due to reshock. Large contributions to enstrophy production during reshock are seen from both the baroclinic source and enstrophy–dilatation terms, highlighting the significance of fluid compressibility in the HED regime. Dimensional analysis reveals that Reynolds numbers and diffusive Péclet numbers in the HED flow are similar to those in a canonical non-HED analogue, but conductive Péclet numbers are much smaller in the HED flow due to efficient thermal conduction by free electrons. It is shown that the mechanism of electron thermal conduction significantly softens local spanwise gradients of both temperature and density, which causes a minor but non-negligible decrease in enstrophy production and small-scale mixing relative to a flow without this mechanism.