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Flutes are flow-parallel till ridges that form subglacially and are conspicuous geomorphic indicators of slip at glacier beds. Flutes commonly have a boulder at their head, lodged in the former till bed of the glacier. In the leading model of flute genesis, weak till of the bed flows into a water-filled cavity where ice separates from the lee surface of the boulder. This cavity is displaced downstream as it progressively fills with till and the flute lengthens. To test this hypothesis, we studied in detail a parallel-sided flute, 250 m long, and a tapered flute, 5 m long, at the surgetype glacier, Múlajökull, in Iceland. More than 900 measurements of till magnetic susceptibility anisotropy, calibrated experimentally, show that spatially averaged till flow converged toward flute long axes, consistent with the cavity-fill hypothesis, and that till shear strains were small (<7.6). Till density patterns indicate that decreasing water pressure in cavities, decreasing slip velocity, and associated increases in ice pressure on the distal ends of the flutes consolidated and strengthened till--an effect far more prominent in the long flute. This till strengthening resolves the fundamental mechanical problem that undermines the cavity-fill hypothesis: how a leeward cavity can be sustained well beyond the pressure shadow in ice created by a boulder. Also resolved is how convergent fabrics in flutes are preserved, despite significant slip of ice across them. These results provide the first evidence that flute elongation beneath wet-based glaciers may require fluctuating water pressure and slip velocity. [ABSTRACT FROM AUTHOR]

Characterizing glaciotectonic deformation, glacial erosion and sedimentation, and basal hydrologic conditions of ice sheets is vital for selecting sites for nuclear waste repositories at high latitudes. Glaciotectonic deformation is enhanced by excess pore pressures that commonly persist near ice sheet margins. Depths of such deformation can extend locally to a few tens of meters, with depths up to approximately 300 m in exceptional cases. Rates of glacial erosion are highly variable (0.05-15 mm a−1), but rates <1 mm a−1 are expected in tectonically quiescent regions. Total erosion probably not exceeding several tens of meters is expected during a glacial cycle, although locally erosion could be greater. Consolidation of glacial sediments that is less than expected from independent estimates of glacier thickness indicates that heads at the bases of past ice sheets were usually within 30% of the floatation value. This conclusion is reinforced by direct measurements of water pressure beneath portions of the West Antarctic ice sheet, which indicate average heads <7 m below floatation. Landforms of the Laurentide and Scandinavian ice sheets and recent observations in Greenland indicate that high seasonal discharges of surface water are conducted to the bed, despite thick ice at subfreezing temperatures. Therefore, in models of subglacial groundwater flow used to assess sites for nuclear waste repositories, a flux upper boundary condition based on water input from only basal melting will be far more uncertain than applying a hydraulic head at the upper boundary set equal to a large fraction of the floatation value. [ABSTRACT FROM AUTHOR]

Hydrothermal explosions are significant potential hazards in Yellowstone National Park, Wyoming, USA. The northern Yellowstone Lake area hosts the three largest hydrothermal explosion craters known on Earth empowered by the highest heat flow values in Yellowstone and active seismicity and deformation. Geological and geochemical studies of eighteen sublacustrine cores provide the first detailed synthesis of the age, sedimentary facies, and origin of multiple hydrothermal explosion deposits. New tephrochronology and radiocarbon results provide a four-dimensional view of recent geologic activity since recession at ca. 15-14.5 ka of the >1-km-thick Pinedale ice sheet. The sedimentary record in Yellowstone Lake contains multiple hydrothermal explosion deposits ranging in age from ca. 13 ka to ~1860 CE. Hydrothermal explosions require a sudden drop in pressure resulting in rapid expansion of high-temperature fluids causing fragmentation, ejection, and crater formation; explosions may be initiated by seismicity, faulting, deformation, or rapid lake-level changes. Fallout and transport of ejecta produces distinct facies of subaqueous hydrothermal explosion deposits. Yellowstone hydrothermal systems are characterized by alkaline-Cl and/or vapor-dominated fluids that, respectively, produce alteration dominated by silica-smectite-chlorite or by kaolinite. Alkaline-Cl liquids flash to steam during hydrothermal explosions, producing much more energetic events than simple vapor expansion in vapor-dominated systems. Two enormous explosion events in Yellowstone Lake were triggered quite differently: Elliott's Crater explosion resulted from a major seismic event (8 ka) that ruptured an impervious hydrothermal dome, whereas the Mary Bay explosion (13 ka) was triggered by a sudden drop in lake level stimulated by a seismic event, tsunami, and outlet channel erosion. [ABSTRACT FROM AUTHOR]

Introduction: Opioid administration is extremely common in the inpatient setting, yet we do not know how the administration of opioids varies across different medical conditions and patient characteristics on internal medicine services. Our goal was to assess racial, ethnic, and language-based inequities in opioid prescribing practices for patients admitted to internal medicine services., Methods: We conducted a retrospective cohort study of all adult patients admitted to internal medicine services from 2013 to 2021 and identified subcohorts of patients treated for the six most frequent primary hospital conditions (pneumonia, sepsis, cellulitis, gastrointestinal bleed, pyelonephritis/urinary tract infection, and respiratory disease) and three select conditions typically associated with pain (abdominal pain, acute back pain, and pancreatitis). We conducted a negative binomial regression analysis to determine how average administered daily opioids, measured as morphine milligram equivalents (MMEs), were associated with race, ethnicity, and language, while adjusting for additional patient demographics, hospitalization characteristics, medical comorbidities, prior opioid therapy, and substance use disorders., Results: The study cohort included 61,831 patient hospitalizations. In adjusted models, we found that patients with limited English proficiency received significantly fewer opioids (66 MMEs, 95% CI: 52, 80) compared to English-speaking patients (101 MMEs, 95% CI: 91, 111). Asian (59 MMEs, 95% CI: 51, 66), Latinx (89 MMEs, 95% CI: 79, 100), and multi-race/ethnicity patients (81 MMEs, 95% CI: 65, 97) received significantly fewer opioids compared to white patients (103 MMEs, 95% CI: 94, 112). American Indian/Alaska Native (227 MMEs, 95% CI: 110, 344) patients received significantly more opioids. Significant inequities were also identified across race, ethnicity, and language groups when analyses were conducted within the subcohorts. Most notably, Asian and Latinx patients received significantly fewer MMEs and American Indian/Alaska Native patients received significantly more MMEs compared to white patients for the top six most frequent conditions. Most patients from minority groups also received fewer MMEs compared to white patients for three select pain conditions. Discussion . There are notable inequities in opioid prescribing based on patient race, ethnicity, and language status for those admitted to inpatient internal medicine services across all conditions and in the subcohorts of the six most frequent hospital conditions and three pain-associated conditions. This represents an institutional and societal opportunity for quality improvement initiatives to promote equitable pain management., Competing Interests: The authors declare that they have no conflicts of interest., (Copyright © 2023 Mihir Joshi et al.)

Hydrogels are excellent water-swollen polymeric materials for use in wearable, implantable, and disposable biosensors. Hydrogels have unique properties such as low cost, ease of preparation, transparency, rapid response to external conditions, biocompatibility and self-adhesion to the skin, flexibility, and strain sensitivity, making them ideal for use in biosensor platforms. This review provides a detailed overview of advanced applications of stimuli-responsive hydrogels in biosensor platforms, from hydrogel synthesis and functionalization for bioreceptor immobilization to several important diagnostic applications. Emphasis is placed on recent advances in the fabrication of ultrasensitive fluorescent and electrically conductive hydrogels and their applications in wearable, implantable, and disposable biosensors for quantitative measurements. Design, modification, and assembly techniques of fluorescent, ionically conductive, and electrically conductive hydrogels to improve performance will be addressed. The advantages and performance improvements of immobilizing bioreceptors (e.g., antibodies, enzymes, and aptamers), and incorporating fluorescent and electrically conductive nanomaterials are described, as are their limitations. Potential applications of hydrogels in implantable, wearable, disposable portable biosensors for quantitative detection of the various bioanalytes (ions, molecules, drugs, proteins, and biomarkers) are discussed. Finally, the global market for hydrogel-based biosensors and future challenges and prospects are discussed in detail., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Background: Though awareness of health care structures that are racist and oppressive is increasing among health care professionals, there is a gap in continuing education curricula focused on antiracist anti-oppressive practices, and limited faculty and staff development to guide individuals towards action., Aim: To develop, implement, and evaluate a novel antiracist faculty and staff development program called the Tea House Series., Setting and Participants: A five-part continuing education series with an accompanying online community for faculty and staff at the divisions of Hospital Medicine in one institution in the western United States., Program Description: The four foundational pillars integral to the Tea House Series were as follows: educational framework based on the pedagogy of Paulo Freire, local disparities data, welcoming space to establish a community of practice and accountability. Each session contained participant dialogue in small group activities., Program Evaluation: Qualitative analysis of participant survey responses demonstrated transformation towards a hope to act with a sense of community. Quantitative analysis measured increased confidence for the program learning objectives., Discussion: The Tea House Series may be used as a model for continuing education to provide the tools and the community to confront systems of racism and oppression in any institution., (© 2022. The Author(s).)

Objectives: Point-of-care ultrasound (POCUS) detects the pulmonary manifestations of COVID-19 and may predict patient outcomes., Methods: We conducted a prospective cohort study at four hospitals from March 2020 to January 2021 to evaluate lung POCUS and clinical outcomes of COVID-19. Inclusion criteria included adult patients hospitalized for COVID-19 who received lung POCUS with a 12-zone protocol. Each image was interpreted by two reviewers blinded to clinical outcomes. Our primary outcome was the need for intensive care unit (ICU) admission versus no ICU admission. Secondary outcomes included intubation and supplemental oxygen usage., Results: N = 160 patients were included. Among critically ill patients, B-lines (94 vs 76%; P < .01) and consolidations (70 vs 46%; P < .01) were more common. For scans collected within 24 hours of admission (N = 101 patients), early B-lines (odds ratio [OR] 4.41 [95% confidence interval, CI: 1.71-14.30]; P < .01) or consolidations (OR 2.49 [95% CI: 1.35-4.86]; P < .01) were predictive of ICU admission. Early consolidations were associated with oxygen usage after discharge (OR 2.16 [95% CI: 1.01-4.70]; P = .047). Patients with a normal scan within 24 hours of admission were less likely to require ICU admission (OR 0.28 [95% CI: 0.09-0.75]; P < .01) or supplemental oxygen (OR 0.26 [95% CI: 0.11-0.61]; P < .01). Ultrasound findings did not dynamically change over a 28-day scanning window after symptom onset., Conclusions: Lung POCUS findings detected within 24 hours of admission may provide expedient risk stratification for important COVID-19 clinical outcomes, including future ICU admission or need for supplemental oxygen. Conversely, a normal scan within 24 hours of admission appears protective. POCUS findings appeared stable over a 28-day scanning window, suggesting that these findings, regardless of their timing, may have clinical implications., (© 2021 American Institute of Ultrasound in Medicine.)

High resolution, rapid, and precise detection of biological analytes related to disease and infection is currently the focus of many researchers. Better biosensors could lead to earlier detection, more avenues of intervention, and higher efficacy of therapeutics, which would lead to better outcomes for all patients. One class of biosensors, single walled carbon nanotubes, is unique due to their nanoscale resolution, single molecule sensitivity, and reversibility for long term applications. While these biosensors have been successful in rodent models, to date, no study has shown successful sensor detection in a large animal. In this study, we show the first successful signal detection of single walled carbon nanotube-based sensors in a large mammal model. Using a relatively simple and cost-effective system, we were able to detect signals in nearly 70% of the sheep used in the study, marking an important steppingstone towards the use of SWNT-based sensors for clinical diagnostics., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Background: Differential opioid prescribing patterns have been reported in non-White patient populations. However, these disparities have not been well described among hospitalized medical inpatients., Objective: To describe differences in opioid prescribing patterns among inpatients discharged from the general medicine service based on race/ethnicity., Design, Setting, and Participants: For this retrospective study, we performed a multivariable logistic regression for patient race/ethnicity and whether patients received an opioid prescription at discharge and a negative binomial regression for days of opioids prescribed at discharge. The study included all 10,953 inpatients discharged from the general medicine service from June 2012 to November 2018 at University of California San Francisco Medical Center who received opioids during the last 24 hours of their hospitalization., Main Outcomes and Measures: We examined two primary outcomes: whether a patient received an opioid prescription at discharge, and, for patients prescribed opioids, the number of days dispensed., Results: Compared with White patients, Black patients were less likely to receive an opioid prescription at discharge (predicted population rate of 47.6% vs 50.7%; average marginal effect [AME], -3.1%; 95% CI, -5.5% to -0.8%). Asian patients were more likely to receive an opioid prescription on discharge (predicted population rate, 55.6% vs 50.7%; AME, +4.9; 95% CI, 1.5%-8.3%). We also found that Black patients received a shorter duration of opioid days compared with White patients (predicted days of opioids on discharge, 15.7 days vs 17.8 days; AME, -2.1 days; 95% CI, -3.3 to -0.9)., Conclusion: Black patients were less likely to receive opioids and received shorter courses at discharge compared with White patients, adjusting for covariates. Asian patients were the most likely to receive an opioid prescription.

Internal medicine (IM) residents frequently see patients in subspecialty clinics. However, there are few published core subspecialty curricula targeted to residents' learning and practical needs, and little guidance exists regarding delivery of core subspecialty content to residents rotating across multiple clinical sites. Our study objective was to evaluate a novel oncology video curriculum for IM residents as a model for asynchronous subspecialty resident learning. Using the cognitive theory of multimedia learning, we developed a five-part oncology video curriculum targeted specifically to the needs of IM residents. All second- and third-year residents rotating in oncology clinics from October 2018 to March 2019 at a single training program were invited to participate. We evaluated curricular demand, efficacy, and acceptability, using completion rates, knowledge tests, and a survey. Twenty-eight of 31 (90.3%) residents utilized the curriculum. Resident knowledge improved after utilizing the modules, by 36.9% from pre- to posttests (95% CI [31.3-42.5]; P<0.001) and 13.7% from pre- to delayed posttests (95% CI [7.5-20.0]; P<0.001). Twenty-four of 31 (77.4%) answered the survey. Most residents agreed or strongly agreed that the curriculum contributed to their knowledge (95.2%) and added educational value beyond the clinical rotation (93.1%). Our curriculum evaluation supports the asynchronous delivery of oncology education targeted to the learning needs of IM residents using a novel core video curriculum. These curricular methods provide a model for delivering subspecialty education to IM residents with complex and busy schedules.

Sensors that can quickly and accurately diagnose and monitor human health are currently at the forefront of medical research. Single walled carbon nanotube (SWNT) based optical biosensors are a growing area of research due to the high spatiotemporal resolution of their near infrared fluorescence leading to high tissue transparency and unparalleled sensitivity to analytes of interest. Unfortunately, due to the functionalization requirements of SWNT-based sensors, there are concerns surrounding accumulation and persistence when applied in vivo. In this study, we developed protocols to extract and quantify SWNT from complex solutions and show an 89% sensor retention by hydrogel platforms when implanted in vivo. Animal tissues of interest were also extracted and probed for SWNT content showing no accumulation (0.03 mg l -1 SWNT detection limit). The methods developed in this paper demonstrated one avenue for applying SWNT sensors in vivo without concern for accumulation.

Introduction: To develop lifelong learning skills, students need feedback, access to performance data, and coaching. A new medical curriculum incorporated infrastructural supports based on self-regulated learning theory and the Master Adaptive Learner framework to engage students in reflection and learning planning. This study examines students' experience with a performance dashboard, longitudinal coaching, and structured time for goal-setting., Methods: Focus groups with first-year medical students explored performance dashboard usage, coaching and learning planning. We analyzed findings using thematic analysis. Results informed development of a 29-item survey rated strongly disagree (1) to strongly agree (5) to investigate experience with the dashboard, coaching and learning goals program. The survey was distributed to one first-year medical student class. We performed descriptive statistics and factor analysis., Results: In three focus groups with 21 participants, students endorsed using the dashboard to access performance information but had trouble interpreting and integrating information. They valued coaches as sources of advice but varied in their perceptions of the value of discussing learning planning. Of 152 students, 114 (75%) completed the survey. Exploratory factor analysis yielded 5 factors explaining 57% of the variance: learning goals development (α = 0.88; mean 3.25 (standard deviation 0.91)), dashboard usage (α = 0.82; 3.36 (0.64)), coaching (α = 0.71; 3.72 (0.64)), employment of learning strategies (α = 0.81; 3.67 (0.79)), and reflection (α = 0.63; 3.68 (0.64))., Discussion: The student performance dashboard provides efficient feedback access, yet students' use of this information to guide learning is variable. These results can inform other programs seeking to foster lifelong learning skills.

Anemia is the defining feature in most patients with myelodysplastic syndromes (MDS), yet defects in erythropoiesis have not been well characterized. We examined freshly obtained bone marrow (BM) samples for stage-specific abnormalities during terminal erythroid differentiation (TED) from 221 samples (MDS, n = 205 from 113 unique patients; normal, n = 16) by measuring the surface expression of glycophorin A, band 3, and integrin α-4. Clinical and biologic associations were sought with presence or absence of TED and the specific stage of erythroid arrest. In 27% of MDS samples (56/205), there was no quantifiable TED documented by surface expression of integrin α-4 and band 3 by terminally differentiating erythroblasts. Absence of quantifiable TED was associated with a significantly worse overall survival (56 vs 103 months, P = .0001) and SRSF2 mutations (7/23, P < .05). In a multivariable Cox proportional hazards regression analysis, absence of TED remained independently significant across International Prognostic Scoring System-Revised (IPSS-R) categories, myeloid/erythroid ratio, and mutations in several genes. In 149/205 MDS samples, the proportion of cells undergoing TED did not follow the expected 1:2:4:8:16 doubling pattern in successive stages. Absence of TED emerged as a powerful independent prognostic marker of poor overall survival across all IPSS-R categories in MDS, and SRSF2 mutations were more frequently associated with absence of TED., (© 2018 by The American Society of Hematology.)