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The paper presents a method for determining electromagnetic parameters of different synchronous generator models based on dynamic waveforms measured at power rejection. Such a test can be performed safely under normal operating conditions of a generator working in a power plant. A generator model was investigated, expressed by reactances and time constants of steady, transient, and subtransient state in the d and q axes, as well as the circuit models (type (3,3) and (2,2)) expressed by resistances and inductances of stator, excitation, and equivalent rotor damping circuits windings. All these models approximately take into account the influence of magnetic core saturation. The least squares method was used for parameter estimation. There was minimized the objective function defined as the mean square error between the measured waveforms and the waveforms calculated based on the mathematical models. A method of determining the initial values of those state variables which also depend on the searched parameters is presented. To minimize the objective function, a gradient optimization algorithm finding local minima for a selected starting point was used. To get closer to the global minimum, calculations were repeated many times, taking into account the inequality constraints for the searched parameters. The paper presents the parameter estimation results and a comparison of the waveforms measured and calculated based on the final parameters for 200 MW and 50 MW turbogenerators.

Background Reliability and validity of the Paprosky classification for acetabular bone loss have been debated. Additionally, the relationship between surgeon training level and Paprosky classification accuracy/treatment selection is poorly defined. This study aimed to: (1) evaluate the validity of preoperative Paprosky classification/treatment selection compared to intraoperative classification/treatment selection and (2) evaluate the relationship between training level and intra-rater and inter-rater reliability of preoperative classification and treatment choice. Methods Seventy-four patients with intraoperative Paprosky types [I ( N  = 24), II ( N  = 27), III ( N  = 23)] were selected. Six raters (Residents ( N  = 2), Fellows ( N  = 2), Attendings ( N  = 2)) independently provided Paprosky classification and treatment using preoperative radiographs. Graders reviewed images twice, 14 days apart. Cohen’s Kappa was calculated for (1) inter-rater agreement of Paprosky classification/treatment by training level (2), intra-rater reliability, (3) preoperative and intraoperative classification agreement, and (4) preoperative treatment selection and actual treatment performed. Results Inter-rater agreement between raters of the same training level was moderate (K range = 0.42–0.50), and mostly poor for treatment selection (K range = 0.02–0.44). Intra-rater agreement ranged from fair to good (K range = 0.40–0.73). Agreement between preoperative and intraoperative classifications was fair (K range = 0.25–0.36). Agreement between preoperative treatment selections and actual treatments was fair (K range = 0.21–0.39). Conclusion Inter-rater reliability of Paprosky classification was poor to moderate for all training levels. Preoperative Paprosky classification showed fair agreement with intraoperative Paprosky grading. Treatment selections based on preoperative radiographs had fair agreement with actual treatments. Further research should investigate the role of advanced imaging and alternative classifications in evaluation of acetabular bone loss.

Methods Familial transmission of panic attacks (PA), PD and AG was examined in a 10-year prospective-longitudinal community study of 3021 adolescents and young adults including completed direct and indirect information on parental psychopathology.

Background Adverse local tissue reaction (ALTR), characterized by a heterogeneous cellular inflammatory infiltrate and the presence of corrosion products in the periprosthetic soft tissues, has been recognized as a mechanism of failure in total hip replacement (THA). Different histological subtypes may have unique needs for longitudinal clinical follow-up and complication rates after revision arthroplasty. The purpose of this study was to describe the histological patterns observed in the periprosthetic tissue of failed THA in three different implant classes due to ALTR and their association with clinical features of implant failure. Methods Consecutive patients presenting with ALTR from three major hip implant classes ( N  = 285 cases) were identified from our prospective Osteolysis Tissue Database and Repository. Clinical characteristics including age, sex, BMI, length of implantation, and serum metal ion levels were recorded. Retrieved synovial tissue morphology was graded using light microscopy. Clinical characteristics and features of synovial tissue analysis were compared between the three implant classes. Histological patterns of ALTR identified from our observations and the literature were used to classify each case. The association between implant class and histological patterns was compared. Results Our histological analysis demonstrates that ALTR encompasses three main histological patterns: 1) macrophage predominant, 2) mixed lymphocytic and macrophagic with or without features of associated with hypersensitivity/allergy or response to particle toxicity (eosinophils/mast cells and/or lymphocytic germinal centers), and 3) predominant sarcoid-like granulomas. Implant classification was associated with histological pattern of failure, and the macrophagic predominant pattern was more common in implants with metal-on-metal bearing surfaces (MoM HRA and MoM LHTHA groups). Duration of implantation and composition of periprosthetic cellular infiltrates was significantly different amongst the three implant types examined suggesting that histopathological features of ALTR may explain the variability of clinical implant performance in these cases. Conclusions ALTR encompasses a diverse range of histological patterns, which are reflective of both the implant configuration independent of manufacturer and clinical features such as duration of implantation. The macrophagic predominant pattern and its mechanism of implant failure represent an important subgroup of ALTR which could become more prominent with increased length of implantation.

Recently, providers have begun to publicly report the results of patient satisfaction surveys from their practices. However, these outcomes have never been compared with the findings of commercial online physician rating websites. The goals of the current study were to (1) compare overall patient satisfaction ratings for orthopedic surgeons derived from provider-based third-party surveys with existing commercial physician rating websites and (2) determine the association between patient ratings and provider characteristics. The authors identified 12 institutions that provided publicly available patient satisfaction outcomes derived from third-party surveys for their orthopedic surgeons as of August 2016. Orthopedic surgeons at these institutions were eligible for inclusion (N=340 surgeons). Provider characteristics were recorded from publicly available data. Four high-traffic commercial online physician rating websites were identified: Healthgrades.com , UCompareHealthCare.com , Vitals.com , and RateMDs.com . For each surgeon, overall ratings (on a scale of 1–5), total number of ratings, and percentage of negative ratings were compared between provider-initiated internal ratings and each commercial online website. Associations between baseline factors and overall physician ratings and negative ratings were assessed. Provider-initiated internal patient satisfaction ratings showed a greater number of overall patient ratings, higher overall patient satisfaction ratings, and a lower percentage of negative comments compared with commercial online physician rating websites. A greater number of years in practice had a weak association with lower internal ratings, and an academic practice setting and a location in the Northeast were protective factors for negative physician ratings. Compared with commercial online physician rating websites, provider-initiated patient satisfaction ratings of orthopedic surgeons appear to be more favorable, with greater numbers of responses. [ Orthopedics. 2017; 40(5):304–310.]

Most published research on informal care for older people focuses on the support provided by relatives. The role of non-kin carers can, however, also be significant in supporting older people in their own homes. In this paper, we report the findings from an exploratory study of the support provided by friends and neighbours who are the main carers of frail older people. It draws on interviews with an opportunistic sample of friends, neighbours and older people, which explored their views about the support arrangements, the reasons why help was provided and any difficulties experienced. Several friends and neighbours provided intensive and frequent help, and some played a key role in co-ordinating other services. One of the main forms of direct support related to older people's quality of life, at a broader level than the practical help provided by statutory services. The flexibility of such support, and the friends' and neighbours' concern for older people as individuals, were particularly important to the people they helped. Nevertheless, such help was not provided without costs to the carers. The study highlights the need for policy-makers and practitioners not to take help from friends and neighbours for granted and, in line with the White Paper Modernising Social Services, to provide the support services they need.

Analysis of power system stabilizer Pareto optimisation-when taking into account the uncertainty of power system mathematical model parameters The paper presents analysis of optimisation results of power system stabilizer (PSS) parameters when taking into account the uncertainty of mathematical model parameters of the power system (PS) elements. The Pareto optimisation was used for optimisation of the system stabilizer parameters. Parameters of five stabilizers of PSS3B type were determined in optimisation process with use of a genetic algorithm with tournament selection. The results obtained were assessed from the point of view of selecting the criterion function. The analysis of influence of the parameter uncertainty on the quality of the results obtained was performed.

A subset of patients undergoing total knee arthroplasty (TKA) for knee osteoarthritis develop debilitating knee stiffness (reduced range of motion) for poorly understood reasons. Dysregulated inflammatory and immune responses to surgery correlate with reduced surgical outcomes, but the dysregulated gene signatures in patients with stiffness after TKA are poorly defined. As a consequence, we are limited in our ability to identify patients at risk of developing poor surgical outcomes and develop preventative approaches. In this pilot study we aimed to identify perioperative blood gene signatures in patients undergoing TKA for knee osteoarthritis and its association with early surgical outcomes, specifically knee range of motion. To do this, we integrated clinical outcomes collected at 6 weeks after surgery with transcriptomics analyses in blood samples collected immediately before surgery and at 24 h after surgery. We found that patients with stiffness at 6 weeks after surgery have a more variable and attenuated circulating gene expression response immediately after surgery. Our results suggest that patients with stiffness following TKA may have distinct gene expression signatures detectable in peripheral blood in the immediate postoperative period.