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After above-knee amputation, the missing biological knee and ankle are commonly replaced with a passive prosthesis, which cannot provide net-positive energy to assist the user. During activities such as sit-to-stand, above-knee amputees must compensate for this lack of power using their upper body, intact limb, and residual limb, resulting in slower, less symmetric, and higher effort movements. Previous studies have shown that powered prostheses can improve symmetry and speed by providing positive assistive power. However, we still lack a systematic investigation of the effect of powered prosthesis assistance. Without this knowledge, researchers and clinicians have no framework for tuning powered prostheses to optimally assist users. Here we show that varying the assistive knee torque significantly affected weight-bearing symmetry, effort, and speed during the stand-up movement in eight above-knee amputees. Specifically, we observed improvements in the index of asymmetry of the vertical ground reaction force at the point approximating maximum vertical center of mass acceleration, the integral of the intact vastus medialis activation measured using electromyography, and the stand-up duration compared to the passive prosthesis. We saw significant improvements in all three metrics when subjects used the powered prosthesis compared to the passive prosthesis. We saw improvements in all three metrics with increasing assistive torque levels commanded by the powered prosthesis. We also observed increased weight-bearing asymmetry at the end of movement, and increased kinematic asymmetry with increasing assistance from the powered prosthesis. These results show that powered prostheses can improve functional mobility, potentially increasing quality of life for millions of people living with above-knee amputations.

A unilateral, lightweight powered hip exoskeleton has been shown to improve walking economy in individuals with above-knee amputations. However, the mechanism responsible for this improvement is unknown. In this study we assess the biomechanics of individuals with above-knee amputations walking with and without a unilateral, lightweight powered hip exoskeleton. We hypothesize that assisting the residual limb will reduce the net residual hip energy.Eight individuals with above-knee amputations walked on a treadmill at 1 m/s with and without a unilateral powered hip exoskeleton. Flexion/extension assistance was provided to the residual hip. Motion capture and inverse dynamic analysis were performed to assess gait kinematics, kinetics, center of mass, and center of pressure.The net energy at the residual hip decreased from 0.05±0.04 J/kg without the exoskeleton to -0.01±0.05 J/kg with the exoskeleton (p = 0.026). The cumulative positive energy of the residual hip decreased on average by 18.2% with 95% confidence intervals (CI) (0.20 J/kg, 0.24 J/kg) and (0.16 J/kg, 0.20 J/kg) without and with the exoskeleton, respectively. During stance, the hip extension torque of the residual limb decreased on average by 37.5%, 95% CI (0.28 Nm/kg, 0.36 Nm/kg), (0.17 Nm/kg, 0.23 Nm/kg) without and with the exoskeleton, respectively.Powered hip exoskeleton assistance significantly reduced the net residual hip energy, with concentric energy being the main contributor to this change. We believe that the reduction in residual hip extension torque during early stance is the main contributor to this reduction.This analysis shows that by assisting the residual hip, the exoskeleton significantly decreased the net hip energy produced by the residual limb, which may explain the improvements in walking economy previously observed.

Emerging robotic knee and ankle prostheses present an opportunity to restore the biomechanical function of missing biological legs, which is not possible with conventional passive prostheses. However, challenges in coordinating the robotic prosthesis movements with the user's neuromuscular system and transitioning between activities limit the real-world viability of these devices. Here we show that a shared neural control approach combining neural signals from the user's residual limb with robot control improves functional mobility in individuals with above-knee amputation. The proposed shared neural controller enables subjects to stand up and sit down under a variety of conditions, squat, lunge, walk, and seamlessly transition between activities without explicit classification of the intended movement. No other available technology can enable individuals with above-knee amputations to achieve this level of mobility. Further, we show that compared to using a conventional passive prosthesis, the proposed shared neural controller significantly reduced muscle effort in both the intact limb (21–51% decrease) and the residual limb (38–48% decrease). We also found that the body weight lifted by the prosthesis side increased significantly while standing up with the robotic leg prosthesis (49%–68% increase), leading to better loading symmetry (43–46% of body weight on the prosthesis side). By decreasing muscle effort and improving symmetry, the proposed shared neural controller has the potential to improve amputee mobility and decrease the risk of falls compared to using conventional passive prostheses.

Powered prostheses can enable individuals with above-knee amputations to ascend stairs step-over-step. To accomplish this task, available stair ascent controllers impose a pre-defined joint impedance behavior or follow a pre-programmed position trajectory. These control approaches have proved successful in the laboratory. However, they are not robust to changes in stair height or cadence, which is essential for real-world ambulation. Here we present an adaptive stair ascent controller that enables individuals with above-knee amputations to climb stairs of varying stair heights at their preferred cadence and with their preferred gait pattern. We found that modulating the prosthesis knee and ankle position as a function of the user’s thigh in swing provides toe clearance for varying stair heights. In stance, modulating the torque-angle relationship as a function of the prosthesis knee position at foot contact provides sufficient torque assistance for climbing stairs of different heights. Furthermore, the proposed controller enables individuals to climb stairs at their preferred cadence and gait pattern, such as step-by-step, step-over-step, and two-step, similar to able-bodied individuals. We anticipate the proposed control strategy will improve the robustness of powered prostheses to environmental and human variance without the need for expert tuning, machine learning, or direct subject intervention, which may enable powered prostheses to more easily move from the lab to the real-world.

Background: Vaginal dryness is a highly prevalent condition. Much of previous research has focused on postmenopausal women. The aim of this study was to evaluate the impact of vaginal dryness on a ...

Motion capture is necessary to quantify gait deviations in individuals with lower-limb amputations. However, access to the patient population and the necessary equipment is limited. Here we present the first open biomechanics dataset for 18 individuals with unilateral above-knee amputations walking at different speeds. Based on their ability to comfortably walk at 0.8 m/s, subjects were divided into two groups, namely K2 and K3. The K2 group walked at [0.4, 0.5, 0.6, 0.7, 0.8] m/s; the K3 group walked at [0.6, 0.8, 1.0, 1.2, 1.4] m/s. Full-body biomechanics was collected using a 10-camera motion capture system and a fully instrumented treadmill. The presented open dataset will enable (i) clinicians to understand the biomechanical demand required to walk with a knee and ankle prosthesis at various speeds, (ii) researchers in biomechanics to gain new insights into the gait deviations of individuals with above-knee amputations, and (iii) engineers to improve prosthesis design and function., Measurement(s)Biomechanics • Kinetics • kinematics • walking • Above-Knee Amputation • transfemoral amputationTechnology Type(s)motion capture system • treadmillFactor Type(s)Medicare Functional Classification Level • walking speedSample Characteristic - OrganismHomo sapiens Machine-accessible metadata file describing the reported data: 10.6084/m9.figshare.12221543

In previous work, molecular dynamics simulations based on a first-principles-derived effective Hamiltonian for Pb1-X(Sc1/2Nb1/2)O3-X (PSN), with nearest-neighbor Pb-O divacancy pairs, was used to calculate X[Pb-O] vs. T, phase diagrams for PSN with: ideal rock-salt type chemical order; nanoscale chemical short-range order; and random chemical disorder. Here, we show that the phase diagrams should include additional regions in which a glassy relaxor-phase (or state) is predicted. With respect to phase diagram topology, these results strongly support the analogy between relaxors and magnetic spin-glass-systems.

To evaluate validity evidence for internal medicine milestone ratings across programs for three resident cohorts by quantifying "not assessable" ratings; reporting mean longitudinal milestone ratings for individual residents; and correlating medical knowledge ratings across training years with certification examination scores to determine predictive validity of milestone ratings for certification outcomes.This retrospective study examined milestone ratings for postgraduate year (PGY) 1-3 residents in U.S. internal medicine residency programs. Data sources included milestone ratings, program characteristics, and certification examination scores.Among 35,217 participants, there was a decreased percentage with "not assessable" ratings across years: 1,566 (22.5%) PGY1s in 2013-2014 versus 1,219 (16.6%) in 2015-2016 (P = .01), and 342 (5.1%) PGY3s in 2013-2014 versus 177 (2.6%) in 2015-2016 (P = .04). For individual residents with three years of ratings, mean milestone ratings increased from around 3 (behaviors of an early learner or advancing resident) in PGY1 (ranging from a mean of 2.73 to 3.19 across subcompetencies) to around 4 (ready for unsupervised practice) in PGY3 (mean of 4.00 to 4.22 across subcompetencies, P.001 for all subcompetencies). For each increase of 0.5 units in two medical knowledge (MK1, MK2) subcompetency ratings, the difference in examination scores for PGY3s was 19.5 points for MK1 (P.001) and 19.0 for MK2 (P.001).These findings provide evidence of validity of the milestones by showing how training programs have applied them over time and how milestones predict other training outcomes.

Robotic ankle-foot prostheses aim to improve the mobility of individuals with belowknee amputations by closely imitating the biomechanical function of the missing biological limb. To accomplish this goal, they must provide biomechanically accurate torque during ambulation. In addition, they must satisfy further requirements such as build height, range of motion (ROM), and weight. These requirements are critical for determining the potential number of users, range of activities that can be performed, and clinical outcomes. Previous studies have proposed addressing this challenge through the use of advanced actuation systems with series and parallel elastic actuators, clutchable leverages, and pneumatic artificial muscles. These ad vanced actuation systems have shown improved mechanical and electrical efficiency compared to conventional servo motors, making powered ankle prostheses possible. However, the improved efficiency comes at the expense of a tall build height, reduced ROM, and significant increase in weight, thus limiting the clinical viability of currently available powered prostheses.

Individuals with lower limb amputations show higher metabolic costs during ambulation than able-bodied individuals. This high metabolic cost may be explained by the inability of available passive prostheses to replicate the biomechanics of intact legs during walking. Powered prostheses promise to address this issue by imitating the power generation of intact legs. Several studies have investigated the effect of power generation and energy injection at the ankle joint in transtibial amputees. In contrast, no study has directly addressed knee power generation in transfemoral amputees. This study investigates the effect of knee power generation in late stance in one transfemoral amputee subject using a lightweight powered prosthesis. Experimental results suggest that injecting positive energy into the gait cycle at the knee level may improve gait ability by reducing effort.

Background The educational milestones were designed as a criterion-based framework for assessing resident progression on the 6 Accreditation Council for Graduate Medical Education competencies. Objective We obtained feedback on, and assessed the construct validity and perceived feasibility and utility of, draft Internal Medicine Milestones for Patient Care and Systems-Based Practice. Methods All participants in our mixed-methods study were members of competency committees in internal medicine residency programs. An initial survey assessed participant and program demographics; focus groups obtained feedback on the draft milestones and explored their perceived utility in resident assessment, and an exit survey elicited input on the value of the draft milestones in resident assessment. Surveys were tabulated using descriptive statistics. Conventional content analysis method was used to assess the focus group data. Results Thirty-four participants from 17 programs completed surveys and participated in 1 of 6 focus groups. Overall, the milestones were perceived as useful in formative and summative assessment of residents. Participants raised concerns about the length and complexity of some draft milestones and suggested specific changes. The focus groups also identified a need for faculty development. In the exit survey, most participants agreed that the Patient Care and Systems-Based Practice Milestones would help competency committees assess trainee progress toward independent practice. Conclusions Draft reporting milestones for 2 competencies demonstrated significant construct validity in both the content and response process and the perceived utility for the assessment of resident performance. To ensure success, additional feedback from the internal medicine community and faculty development will be necessary.

William Iobst, MD, is Vice President of Academic Affairs, American Board of Internal Medicine; Eve Aagaard, MD, is Associate Professor of Medicine, University of Colorado School of Medicine; Hasan Bazari, MD, is Program Director, Internal Medicine Residency Program, Massachusetts General Hospital, and Associate Professor of Medicine, Harvard Medical School; Timothy Brigham, MDiv, PhD, is Chief of Staff and Senior Vice President, Department of Education, Accreditation Council for Graduate Medical Education; Roger W. Bush, MD, is Attending Physician, Virginia Mason Medical Center; Kelly Caverzagie, MD, is Assistant Professor of Medicine and Associate Vice Chair for Quality and Physician Competence, Department of Internal Medicine, University of Nebraska Medical Center; Davoren Chick, MD, is Clinical Assistant Professor of Medicine, Department of Internal Medicine, University of Michigan Medical School; Michael Green, MD, is Professor of Medicine, Yale University School of Medicine; Kevin Hinchey, MD, is Associate Professor, Tufts University School of Medicine, and Chief Academic Officer, Baystate Medical Center; Eric Holmboe, MD, is Chief Medical Officer, American Board of Internal Medicine; Sarah Hood, MS, is Director of Academic Affairs, American Board of Internal Medicine; Gregory Kane, MD, is Professor of Medicine, Interim Chairman of the Department of Medicine, Jefferson Medical College; Lynne Kirk, MD, is Professor of Internal Medicine, University of Texas Southwestern Medical Center; Lauren Meade, MD, is Assistant Professor of Medicine, Tufts University School of Medicine, and Associate Program Director for Internal Medicine, Baystate Medical Center, and Chair of Educational Research Outcomes Collaborative–Internal Medicine; Cynthia Smith, MD, is Senior Medical Associate for Content Development, American College of Physicians, and Adjunct Associate Professor, Perelman School of Medicine; and Susan Swing, PhD, is Vice President, Outcome Assessment, Accreditation Council for Graduate Medical Education.

High-quality assessment of resident performance is needed to guide individual residents' development and ensure their preparedness to provide patient care. To facilitate this aim, reporting milestones are now required across all internal medicine (IM) residency programs.To describe initial milestone ratings for the population of IM residents by IM residency programs.Cross-sectional study.IM residency programs.All IM residents whose residency program directors submitted milestone data at the end of the 2013-2014 academic year.Ratings addressed 6 competencies and 22 subcompetencies. A rating of "not assessable" indicated insufficient information to evaluate the given subcompetency. Descriptive statistics were calculated to describe ratings across competencies and training years.Data were available for all 21 774 U.S. IM residents from all 383 programs. Overall, 2889 residents (1621 in postgraduate year 1 [PGY-1], 902 in PGY-2, and 366 in PGY-3) had at least 1 subcompetency rated as not assessable. Summaries of average ratings by competency and training year showed higher ratings for PGY-3 residents in all competencies. Overall ratings for each of the 6 individual competencies showed that fewer than 1% of third-year residents were rated as "unsatisfactory" or "conditional on improvement." However, when subcompetency milestone ratings were used, 861 residents (12.8%) who successfully completed training had at least 1 competency with all corresponding subcompetencies graded below the threshold of "readiness for unsupervised practice."Data were derived from a point in time in the first reporting period in which milestones were used.The initial milestone-based evaluations of IM residents nationally suggest that documenting developmental progression of competency is possible over training years. Subcompetencies may identify areas in which residents might benefit from additional feedback and experience. Future work is needed to explore how milestones are used to support residents' development and enhance residency curricula.None.

Objective. To investigate the feasibility, reliability, and validity of comprehensively assessing physician-level performance in ambulatory practice. Data Sources/Study Setting. Ambulatory-based general internists in 13 states participated in the assessment. Study Design. We assessed physician-level performance, adjusted for patient factors, on 46 individual measures, an overall composite measure, and composite measures for chronic, acute, and preventive care. Between- versus within-physician variation was quantified by intraclass correlation coefficients (ICC). External validity was assessed by correlating performance on a certification exam. Data Collection/Extraction Methods. Medical records for 236 physicians were audited for seven chronic and four acute care conditions, and six age- and gender-appropriate preventive services. Principal Findings. Performance on the individual and composite measures varied substantially within (range 5–86 percent compliance on 46 measures) and between physicians (ICC range 0.12–0.88). Reliabilities for the composite measures were robust: 0.88 for chronic care and 0.87 for preventive services. Higher certification exam scores were associated with better performance on the overall (r=0.19; p

Hypersentimentality to possessions has been proposed to play an important role in the development and maintenance of compulsive hoarding. The current study prospectively examined the formation of attachment to a newly acquired object in an OCD sample (n = 62) to determine whether specific hoarding symptoms moderated the development of attachment to an object over time. Participants rated their level of attachment to a keychain immediately upon receipt (time 1) and one week later (time 2). We hypothesized that individuals with a tendency to hoard and strong beliefs about the value of possessions would exhibit greater attachment to the object over time. Hierarchical multiple regression analyses revealed that a person's initial attachment to the object was the best predictor of attachment one week later. Although emotional attachment increased similarly for all participants independent of their hoarding symptoms, specific hoarding-related beliefs and behaviors uniquely predicted initial attachment to the keychain.

Importance US internal medicine residency programs are now required to rate residents using milestones. Evidence of validity of milestone ratings is needed. Objective To compare ratings of internal medicine residents using the pre-2015 resident annual evaluation summary (RAES), a nondevelopmental rating scale, with developmental milestone ratings. Design, Setting, and Participants Cross-sectional study of US internal medicine residency programs in the 2013-2014 academic year, including 21 284 internal medicine residents (7048 postgraduate-year 1 [PGY-1], 7233 PGY-2, and 7003 PGY-3). Exposures Program director ratings on the RAES and milestone ratings. Main Outcomes and Measures Correlations of RAES and milestone ratings by training year; correlations of medical knowledge ratings with American Board of Internal Medicine (ABIM) certification examination scores; rating of unprofessional behavior using the 2 systems. Results Corresponding RAES ratings and milestone ratings showed progressively higher correlations across training years, ranging among competencies from 0.31 (95% CI, 0.29 to 0.33) to 0.35 (95% CI, 0.33 to 0.37) for PGY-1 residents to 0.43 (95% CI, 0.41 to 0.45) to 0.52 (95% CI, 0.50 to 0.54) for PGY-3 residents (all P values P values P P P P Conclusions and Relevance Among US internal medicine residents in the 2013-2014 academic year, milestone-based ratings correlated with RAES ratings but with a greater difference across training years. Both rating systems for medical knowledge correlated with ABIM certification examination scores. Milestone ratings may better detect problems with professionalism. These preliminary findings may inform establishment of the validity of milestone-based assessment.

Although compulsive hoarding appears to be a chronic, progressive disorder, little is known about its onset and course. The current study employed retrospective assessment of 51 individuals with compulsive hoarding difficulties to determine onset of various hoarding symptoms (clutter, acquisition, difficulty discarding), as well as the individual's degree of recognition of the problem at various times throughout his or her life. Participants were asked to describe life events from each decade that occurred at the time hoarding symptoms were developing. Symptoms of clutter and difficulty discarding appeared to begin at approximately the same age, whereas acquiring problems began slightly later. Recognition of the problem developed significantly later than any of the symptoms themselves. A portion of participants reported that their hoarding symptoms were reduced at some point in their lives, but few reported full remission of hoarding at any point. Survival analysis of age of onset of hoarding symptoms indicated that individuals who reported a stressful event when saving behavior started had a significantly later age of onset than those who reported no events at the age of onset. Perhaps for some individuals compulsive hoarding is a lifelong characterological phenomenon, whereas for others hoarding behavior develops later as a reaction to stress or loss.

The Accreditation Council for Graduate Medical Education (ACGME) developed the Milestones Project to facilitate more synthetic and narrative-based assessments of educational outcomes. This commenta...