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As a summary and extension of previous work on arching in granular heaps, an analysis is given of statically admissible stress distributions in infinite planar wedges and axisymmetric cones composed of an Isotropie linear-elastic material subject to a noncohesive Mohr-Coulomb yield criterion. The treatment is based on a combination of analytical solutions for elastic and simple plastic states, together with numerical integration of the (Sokolovskii-Kötter) ordinary differential equations appropriate to more complex plastic states. For wedges, we obtain a one-parameter family of continuous elastoplastic solutions, with only three isolated symmetric solutions for symmetric wedges, one of which has a central pressure dip or 'arch'. For axisymmetric cones subject to a well-known closure for plastic hoop stress, only one continuous elastoplastic state is found, and it exhibits an arch. In addition to the above continuous solutions, a class of discontinuous plasticlimit states is considered, which exhibit a central pressure dip associated with the discontinuous transition from active to passive states proposed by Savage. The only solutions of this type found for symmetric wedges and cones involve central pressure dips. A brief discussion is given of the relation of this work to an extensive recent literature on the central pressure dip observed in certain experiments on granular heaps. © 2000 The Royal Society.

This paper is concerned with the Reynolds dilatancy and shear strength of idealized granular media. The first part of the paper offers a calculation of dilatancy in rigid-sphere assemblies based on the theoretical estimate previously proposed by J. D. Goddard (Proc. 11th Int. Congress of Rheology (ed. P. Moldenaers and R. Kuenings; Elsevier, Amsterdam 1992) 141-142) as a generalization of the classical work of O. Reynolds (Phil. Mag. 20 (1885) 469-481). This new estimate yields an analytical expression for the dilatancy of two-dimensional isotropic assemblies of disks with arbitrary size distribution. Only a few special cases of three-dimensional assemblies could be treated analytically, but a stochastic (Monte Carlo) calculation is readily implemented. The estimates of the present method are roughly three times those of Reynolds, and it is argued that the two types of estimate represent opposite bounds for the dilatancy and strength of frictionless sphere assemblies. The second part of the paper summarizes results from a detailed particle-mechanics (discrete-element) computer simulation of rigid-sphere assemblies, based on the recently developed quasi-static method of Zhuang, Didwania and Goddard (J. Comput. Phys. 121 (1995) 331-346). Dilatancies and yield cones are computed for various mono- and polydisperse assemblies of rigid frictional spheres subject to simple monotonic deformations, of the type encompassed by the 'cubical triaxial' test of soil mechanics. At large plastic strains, the computed yield surfaces bear a striking resemblance to the empirical Lade-Duncan yield surface of soil mechanics, which is adopted as a convenient referential basis for presenting the simulations. Many of the computed yield cones exhibit a lack of convexity at small strain, which may suggest a plastic instability that is suppressed in the current simulations, a matter proposed for further investigation. The results presented here suggest that frictional-sphere assemblies... [ABSTRACT FROM AUTHOR]

Background: "One-minute preceptor" (OMP) is a well-established educational technique; however, primary literature on OMP lacks a tool to assess behavioral change after delivery of curricula.Primary aim of this pilot study was to design a checklist for direct observation of teachers using OMP on general medicine rounds and obtain inter-rater reliability evidence for the checklist., Methods: This study pilots an internally designed 6-item checklist to assess change in directly observed behavior. We describe the process of developing the checklist and training the observers. We calculated a percent agreement and Cohen's kappa to assess inter-rater reliability., Results: Raters had a high percent agreement ranging from 0.8 to 0.9 for each step of OMP. Cohen's kappa ranged from 0.49 to 0.77 for the five OMP steps. The highest kappa obtained was for getting a commitment (κ = 0.77) step, whereas the lowest agreement was for correcting mistakes (κ = 0.49)., Conclusion: We showed a percent agreement ≥0.8 and moderate agreement based on Cohen's kappa with most steps of OMP on our checklist. A reliable OMP checklist is an important step in further improving the assessment and feedback of resident teaching skills on general medicine wards., Competing Interests: Disclosures: The authors declare no conflict of interest., (Copyright © 2022 The Alliance for Continuing Education in the Health Professions, the Association for Hospital Medical Education, and the Society for Academic Continuing Medical Education.)

Background: Residency programs apply varying criteria to the resident selection process. However, it is unclear which applicant characteristics reflect preparedness for residency., Objective: We determined the applicant characteristics associated with first-year performance in internal medicine residency as assessed by performance on Accreditation Council for Graduate Medical Education (ACGME) Milestones., Methods: We examined the association between applicant characteristics and performance on ACGME Milestones during intern year for individuals entering Northwestern University's internal medicine residency between 2013 and 2018. We used bivariate analysis and a multivariable linear regression model to determine the association between individual factors and Milestone performance., Results: Of 203 eligible residents, 198 (98%) were included in the final sample. One hundred fourteen residents (58%) were female, and 116 residents (59%) were White. Mean Step 1 and Step 2 CK scores were 245.5 (SD 12.0) and 258 (SD 10.8) respectively. Step 1 scores, Alpha Omega Alpha membership, medicine clerkship grades, and interview scores were not associated with Milestone performance in the bivariate analysis and were not included in the multivariable model. In the multivariable model, overall clerkship grades, ranking of the medical school, and year entering residency were significantly associated with Milestone performance ( P ≤ .04)., Conclusions: Most traditional metrics used in residency selection were not associated with early performance on ACGME Milestones during internal medicine residency., Competing Interests: Conflict of interest: The authors declare they have no competing interests.

Background: Understanding factors in internal medicine (IM) resident career choice may reveal important needed interventions for recruitment and diversity in IM primary care and its subspecialties. Self-reported learner confidence is higher in men than in women in certain areas of practicing medicine, but has never been explored as a factor in career choice., Objective: The purpose of this study is to elucidate associations between confidence, gender, and career choice., Design: IM residents completed a 31-item survey rating confidence in procedural, clinical, and communication skills on a 9-point Likert scale. Residents also reported anticipated career choice and rated influence of factors. Associations between gender and confidence scale scores, gender and career choice, and confidence and career choice were analyzed using t tests, ANOVA, and multiple linear regression controlled for postgraduate year (PGY), institution, and specialty choice., Participants: 292 IM residents at Northwestern and University of Texas (UT) Southwestern MAIN MEASURES: Resident gender, self-reported confidence, career choice KEY RESULTS: Response rate was 79.6% (n = 292), of them 50.3% women. Overall self-reported confidence increased with training (PGY-1 4.9 (1.1); PGY-2 6.2 (1.0); PGY-3 7.4 (1.0); p < 0.001). Men had higher confidence than women (men 6.6 (1.5); women 6.3 (1.4), p = 0.06), with the greatest difference in procedures. High confidence in men was associated with choice of procedural careers, whereas there was no association between confidence and career in women., Conclusions: This is the first study demonstrating a gender difference in self-reported confidence and career choice. There is a positive correlation in men: higher self-reported confidence with procedural specialties, lower with general internal medicine. Women's self-reported confidence had no association. Further investigation is needed to elucidate causative factors for differences in self-reported confidence by gender, and whether alterations in level of self-reported confidence produce a downstream effect on career choice.

Objectives: Simulation-based mastery learning (SBML) programs have been shown to be beneficial to improve procedural skill acquisition. However, simulated procedure performance can be affected by a host of factors, including stress. This investigation examined the preliminary efficacy of bolstering an established SBML program for medical residents with a brief mindfulness intervention (called a PITSTOP) to reduce procedural stress and improve simulator performance. Design: The study employed a partially blinded, parallel-group, randomized, repeated-measures intention-to-treat design. Participants were blinded to the primary outcome (simulator performance) and instead were informed of the study's secondary outcome (stress prevention). The SBML faculty instructors and study investigators were blinded to participants' group assignment. Settings/location: Northwestern Memorial Hospitals of Chicago. Subjects: Twenty-six postgraduate year (PGY) 1 internal medicine residents enrolled in a required SBML central venous catheter (CVC) insertion training from June 2015 to January 2018 participated in the study. Interventions: SBML consists of a simulated skills pretest, deliberate practice, and a simulated skills post-test (within 1 week of pretest). PGY 1 participants were randomly assigned to the PITSTOP intervention (12-min PITSTOP mindfulness training video) or control group (12-min control video on ways to increase physical activity) before the SBML pretest. Outcome measures: The primary outcome was a comparison of each group's simulator performance during pre- and post-tests. Secondary outcomes were changes in groups' procedural stress during these tests (assessed using self-reported, instructor-rated, and physiologic indicators), and self-reported self-regulation outcomes. Results: Residents who watched the PITSTOP video before their SBML training made fewer procedural errors relative to controls during their pretest for intrajugular CVC insertion ( p  = 0.03). PITSTOP participants also had lower heart rate ( p  = 0.03) and less visible trembling ( p  = 0.003) relative to controls at the post-test. Conclusions: This study provides preliminary evidence that a brief, mindfulness intervention may reduce stress during SBML training.

Background: Underrepresented minority (URM) trainees face unique challenges in academic medicine. Near-peer mentorship is an under-described method to support URM trainees., Objective: We created and evaluated the Student to Resident Institutional Vehicle for Excellence (STRIVE) program in a large urban medical school and associated residency programs., Methods: All URM residents were invited to participate in the STRIVE mentorship program consisting of 3 pillars of programming: medical school curriculum review sessions, panel discussions, and social events for medical students. The program was evaluated through participation rates and a 7-item survey delivered in May 2019 after 3 years of implementation., Results: The STRIVE initiative conducted 25 events. Thirty-five of 151 eligible (23%) URM residents participated as mentors for an average of 50 of 110 eligible (45%) URM medical students annually. Resident mentors participated for an average of 3 to 4 hours each year. Twenty of 32 eligible resident mentors (63%) completed the survey. Ninety-five percent (19 of 20) of survey respondents agreed that STRIVE made them a better mentor; 90% (18 of 20) reported that they would have appreciated an equivalent program during their medical school training; and 75% (15 of 20) agreed that the program helped them address the challenges of underrepresentation in medicine., Conclusions: Over a 3-year period, STRIVE required a modest amount of resident time and was valued by the URM residents and medical students who participated in the program., Competing Interests: Conflict of interest: The authors declare they have no competing interests., (Accreditation Council for Graduate Medical Education 2020.)

Background: Although many studies of quality improvement (QI) education programmes report improvement in learners' knowledge and confidence, the impact on learners' future engagement in QI activities is largely unknown and few studies report project measures beyond completion of the programme., Method: We developed the Academy for Quality and Safety Improvement (AQSI) to prepare individuals, across multiple departments and professions, to lead QI. The 7-month programme consisted of class work and team-based project work. We assessed participants' knowledge using a multiple choice test and an adapted Quality Improvement Knowledge Assessment Test (QIKAT) before and after the programme. We evaluated participants' postprogramme QI activity and project status using surveys at 6 and 18 months., Results: Over 5 years, 172 individuals and 32 teams participated. Participants had higher multiple choice test (71.9±12.7 vs 79.4±13.2; p<0.001) and adapted QIKAT scores (55.7±16.3 vs 61.8±14.7; p<0.001) after the programme. The majority of participants at 6 months indicated that they had applied knowledge and skills learnt to improve quality in their clinical area (129/148; 87.2%) and to implement QI interventions (92/148; 62.2%). At 18 months, nearly half (48/101; 47.5%) had led other QI projects and many (41/101; 40.6%) had provided QI mentorship to others. Overall, 14 (43.8%) teams had positive postintervention results at AQSI completion and 20 (62.5%) had positive results at some point (ie, completion, 6 months or 18 months after AQSI)., Conclusions: A team-based QI training programme resulted in a high degree of participants' involvement in QI activities beyond completion of the programme. A majority of team projects showed improvement in project measures, often occurring after completion of the programme., Competing Interests: Competing interests: None declared., (© Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2019. All rights reserved. No commercial use is permitted unless otherwise expressly granted.)

A young previously healthy patient presented with fever and altered mental status. Her evaluation would eventually reveal a profound hyponatremia in the setting of a viral meningoencephalitis. This case report reviews the evaluation of hyponatremia and treatment options for syndrome of inappropriate antidiuretic hormone hypersecretion, her ultimate diagnosis.

Importance: In 2003, the first phase of duty hour requirements for US residency programs recommended by the Accreditation Council for Graduate Medical Education (ACGME) was implemented. Evidence suggests that this first phase of duty hour requirements resulted in a modest improvement in resident well-being and patient safety. To build on these initial changes, the ACGME recommended a new set of duty hour requirements that took effect in July 2011., Objective: To determine the effects of the 2011 duty hour reforms on first-year residents (interns) and their patients., Design: As part of the Intern Health Study, we conducted a longitudinal cohort study comparing interns serving before (2009 and 2010) and interns serving after (2011) the implementation of the new duty hour requirements., Setting: Fifty-one residency programs at 14 university and community-based GME institutions., Participants: A total of 2323 medical interns., Main Outcome Measures: Self-reported duty hours, hours of sleep, depressive symptoms, well-being, and medical errors at 3, 6, 9, and 12 months of the internship year., Results: Fifty-eight percent of invited interns chose to participate in the study. Reported duty hours decreased from an average of 67.0 hours per week before the new rules to 64.3 hours per week after the new rules were instituted (P < .001). Despite the decrease in duty hours, there were no significant changes in hours slept (6.8 → 7.0; P = .17), depressive symptoms (5.8 → 5.7; P = .55) or well-being score (48.5 → 48.4; P = .86) reported by interns. With the new duty hour rules, the percentage of interns who reported concern about making a serious medical error increased from 19.9% to 23.3% (P = .007)., Conclusions and Relevance: Although interns report working fewer hours under the new duty hour restrictions, this decrease has not been accompanied by an increase in hours of sleep or an improvement in depressive symptoms or well-being but has been accompanied by an unanticipated increase in self-reported medical errors.

Background: Unprofessional behaviors undermine the hospital learning environment and quality of patient care., Objective: To quantify perceptions of, and participation in, unprofessional behaviors among hospitalists., Design: Observational survey study., Setting: Three academic health centers., Subjects: Hospitalists., Measurements: Observation, participation in, and perceptions of unprofessional behaviors., Results: Response rate was 76% (77/101). Nearly all behaviors were perceived as unprofessional ("unprofessional" or "somewhat unprofessional" on the Likert scale). Participation in egregious behaviors (ie, falsifying records) was low (<5%). The most frequent behaviors reported were having personal conversations in patient corridors (67.1%), ordering a test as "urgent" to expedite care (62.3%), and making fun of other physicians (40.3%). Four factors accounted for 76% of survey variance: (1) making fun of others; (2) learning environment (eg, texting during conferences); (3) workload management (eg, celebrating a blocked-admission); and (4) time pressure (eg, signing out work early). Hospitalists with less clinical time (<50% full-time equivalents [FTE]) were more likely to report making fun of others (β = 0.94 [95% CI 0.32-1.56], P = 0.004). Younger hospitalists (β = 0.87 [95% CI 0.07-1.67], P = 0.034) and those with administrative time (β = 0.61 [95% CI 0.11-1.10], P = 0.017) were more likely to report participating in workload management behaviors. Hospitalists who work night shifts were more likely to report participating in time-pressure behaviors (β = 0.67 [95% CI 0.17-1.17], P = 0.010). Workload management and learning environment varied by site., Conclusion: While hospitalist participation in unprofessional behaviors is low, job characteristics (clinical, administrative, nights), age, and site were associated with different types of unprofessional behavior that may affect the learning environment and patient care., (Copyright © 2012 Society of Hospital Medicine.)