588 research outputs found

    Disorder Induced Stripes in d-Wave Superconductors

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    Stripe phases are observed experimentally in several copper-based high-Tc superconductors near 1/8 hole doping. However, the specific characteristics may vary depending on the degree of dopant disorder and the presence or absence of a low- temperature tetragonal phase. On the basis of a Hartree-Fock decoupling scheme for the t-J model we discuss the diverse behavior of stripe phases. In particular the effect of inhomogeneities is investigated in two distinctly different parameter regimes which are characterized by the strength of the interaction. We observe that small concen- trations of impurities or vortices pin the unidirectional density waves, and dopant disorder is capable to stabilize a stripe phase in parameter regimes where homogeneous phases are typically favored in clean systems. The momentum-space results exhibit universal features for all coexisting density-wave solutions, nearly unchanged even in strongly disordered systems. These coexisting solutions feature generically a full energy gap and a particle-hole asymmetry in the density of states.Comment: 28 pages, 8 figure

    Seasonal variation in adult hip disease secondary to osteoarthritis and developmental dysplasia of the hip

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    AIM: To determine if there was a seasonal variation in adults undergoing total hip arthroplasty for end stage hip disease due to osteoarthritis (OA) or sequelae of developmental dysplasia of the hip (DDH). METHODS: The total hip registry from the author's institution for the years 1969 to 2013 was reviewed. The month of birth, age, gender, and ethnicity was recorded. Differences between number of births observed and expected in the winter months (October through February) and non-winter mo (March through September) were analyzed with the χ2 test. Detailed temporal variation was mathematically assessed using cosinor analysis. RESULTS: There were 7792 OA patients and 60 DDH patients who underwent total hip arthroplasty. There were more births than expected in the winter months for both the DDH (P < 0.0001) and OA (P = 0.0052) groups. Cosinor analyses demonstrated a peak date of birth on 1st October. CONCLUSION: These data demonstrate an increased prevalence of DDH and OA in those patients born in winter

    Litigation involving patients with slipped capital femoral epiphysis

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    Background Slipped capital femoral epiphysis (SCFE) is a hip disorder of late childhood and adolescence. Litigation involving SCFE may occur, as it is frequently diagnosed late, and/or may be temporally related to an injury. The purpose of this study was to review litigation cases involving SCFE in the US, focusing on the type of litigation (professional, premise, or product liability), the outcome of the litigation and indemnity payouts. Methods Cases of litigation involving SCFE were identified using 5 legal databases and Google Scholar searching for the term “slipped capital femoral epiphysis”. These databases originated as early as 1973. The data collected was the alleged complaint, type of defendant, outcome, state where filed, and amount of indemnity payout. Payout amounts were converted to 2020 US.StatisticalanalyseswereperformedwithSYSTAT®10software.ResultsTherewere135uniquecasesidentifiedwhichinvolvedprofessionalliability(103),premiseliability(30),bothpremiseandprofessionalliability(1),andproductliability(1).Complaintsforprofessionalliabilitycaseswereallegedfailureindiagnosis(71),inappropriatetreatment(14),bothdiagnosisandtreatment(12),andothers(7).Thedelayinthosewithanallegedlatediagnosis(37cases)was5.8months.Thethreemostcommonspecialtiesnamedasdefendant(s)wereprimarycare(31. Statistical analyses were performed with SYSTAT® 10 software. Results There were 135 unique cases identified which involved professional liability (103), premise liability (30), both premise and professional liability (1), and product liability (1). Complaints for professional liability cases were alleged failure in diagnosis (71), inappropriate treatment (14), both diagnosis and treatment (12), and others (7). The delay in those with an alleged late diagnosis (37 cases) was 5.8 months. The three most common specialties named as defendant(s) were primary care (31%), orthopaedic surgeons (29%), and radiologists (16%). The primary allegations against non-orthopaedic surgeons were failure in diagnosis (89%) as opposed to orthopaedic surgeons where the complaints of alleged failures in diagnosis and inappropriate treatment were equal (50%). The geographic region of the filed cases was the Northeast (44%), South (24%), Midwest (16%), and West (16%). There were no differences between premise and professional liability cases by geographic region. The overall outcome was favorable for the defendant(s) in 53% and the plaintiff in 47%; the defense prevailed in 60% of the professional liability but only 33% of the premise liability cases. The indemnity payout amount (for the 52 cases where known) averaged 1.28 million. Payout was higher in the complaints for professional compared to premise liability (1.5vs.1.5 vs. 0.9 million). The average payout for those with and without avascular necrosis was 2.97millionvs.2.97 million vs. 1.02 million. For the professional liability claims, indemnity payout was most frequent in the Western US. It must be remembered that this study only represents law suits filed in the US court system. It does not include cases that might have been resolved prior to any legal action as those cases are not publicly available. Conclusions Reported litigation involving SCFE patients involved claims of professional liability in 77% and premise liability in 22% of located cases. Due to significant exposure, this study should serve as a reminder to all health care providers to include SCFE in the differential diagnosis of knee/thigh pain in adolescents

    BMJ Open

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    Objectives To investigate authors’ awareness and use of authorship guidelines, and to assess their perceptions of the fairness of authorship decisions. Design A cross-sectional online survey. Setting and participants Corresponding authors of research papers submitted in 2014 to 18 BMJ journals. Results 3859/12 646 (31%) researchers responded. They worked in 93 countries and varied in research experience. Of these, 1326 (34%) reported their institution had an authorship policy providing criteria for authorship; 2871 (74%) were ‘very familiar’ with the International Committee of Medical Journal Editors’ authorship criteria and 3358 (87%) reported that guidelines were beneficial when preparing manuscripts. Furthermore, 2609 (68%) reported that their use was ‘sometimes’ or ‘frequently’ encouraged in their research setting. However, 2859 respondents (74%) reported that they had been involved in a study at least once where someone was added as an author who had not contributed substantially (honorary authorship), and 1305 (34%) where someone was not listed as an author but had contributed substantially (ghost authorship). Only 740 (19%) reported that they had never experienced either honorary or ghost authorship; 1115 (29%) reported that they had experienced both at least once. There was no clear pattern in experience of authorship misappropriation by continent. For their last coauthored article, 2187 (57%) reported that explicit authorship criteria had been used to determine eligibility, and 3088 (80%) felt that the decision made was fair. When institutions frequently encouraged use of authorship guidelines, authorship eligibility was more likely to be discussed early (817 of 1410, 58%) and perceived as fairer (1273 of 1410, 90%) compared with infrequent encouragement (974 of 2449, 40%, and 1891 of 2449, 74%). Conclusions Despite a high level of awareness of authorship guidelines and criteria, these are not so widely used; more explicit encouragement of their use by institutions may result in more favourable use of guidelines by authors

    Authorship Trends in the Journal of Orthopaedic Research: A Bibliometric Analysis

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    Publications are an important tool to measure one's success and achievement in academia. They can help propel a career forward and move one into a position of leadership. The overall purpose of this study was to investigate changes in bibliometric variables, authorship, and collaboration trends in the Journal of Orthopaedic Research (JOR®), since its inception in 1983. A bibliometric analysis was completed for all manuscripts meeting the inclusion criteria (638), which were published throughout the inaugural year plus one representative year of each decade. Several parameters were investigated including numbers of manuscripts, authors, collaborating institutions/countries, references, pages, and citations; region of origin and gender of authors over time and by region were main focuses. Significant increases over time were observed in all bibliometric variables analyzed except in the number of pages and citations. There was an approximate 27 percentage point increase for both female first and corresponding authors from 1983 to 2015. While this is most likely due to the increase in the number of women that have entered the field over time, similar increases in the percentage of women holding positions on the JOR editorial board or in leadership positions within in the field may have also contributed to improvements in gender parity. Understanding changes in publishing characteristics over time, by region, and by gender are critical, especially with the rising demands of publishing in academia. JOR has seen increase in most variables analyzed, including improvements in authorship by women in the field of orthopaedic research

    Bibliometric Analysis of Female Authorship Trends and Collaboration Dynamics Over JBMR's 30-Year History

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    In academia, authorship is considered a currency and is important for career advancement. As the Journal of Bone and Mineral Research (JBMR) is the highest-ranked journal in the field of bone, muscle, and mineral metabolism and is the official publication of the American Society for Bone and Mineral Research, we sought to examine authorship changes over JBMR's 30-year history. Two bibliometric methods were used to collect the data. The “decade method” included all published manuscripts throughout 1 year in each decade over the past 30 years starting with the inaugural year, yielding 746 manuscripts for analysis. The “random method” examined 10% of published manuscripts from each of the 30 years, yielding 652 manuscripts for analysis. Using both methods, the average number of authors per manuscript, numerical location of the corresponding author, number of collaborating institutions, number of collaborating countries, number of printed manuscript pages, and the number of times each manuscript was cited all significantly increased between 1986 and 2015 (p < 10−4). Using the decade method, there was a significant increase in the percentage of female first authors over time from 35.8% in 1986 to 47.7% in 2015 (p = 0.02), and this trend was confirmed using the random method. The highest percentage of female first authors in 2015 was in Europe (60.0%), and Europe also had the most dramatic increase in female first authors over time (more than double in 2015 compared with 1986). Likewise, the overall number of female corresponding authors significantly increased during the past 30 years. With the increasing demands of publishing in academic medicine, understanding changes in publishing characteristics over time and by geographical region is important. These findings highlight JBMR's authorship trends over the past 30 years and demonstrate those countries having the most changes and where challenges still exist
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