213 research outputs found
Global convergence of a primal-dual interior-point method for nonlinear programming
Many recent convergence results obtained for primal-dual interior-point methods for nonlinear programming, use assumptions of the boundedness of generated iterates. In this paper we replace such assumptions by new assumptions on the NLP problem, develop a modification of a primal-dual interior-point method implemented in software package LOQO and analyze convergence of the new method from any initial guess
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The effect of brief self-management intervention for hemodialysis patients (HED-SMART) on trajectories of depressive and anxious symptoms
Objective: Depression is often comorbid with End-Stage Renal Disease, and associated with poor adherence and clinical outcomes but course of symptoms is variable. This study sought to describe the long-term trajectories of anxiety and depression in hemodialysis patients, to identify predictors of these trajectories over 12 months and to evaluate the effectiveness of the HEmoDialysis Self-Management Randomized Trial (HED SMART) against usual care on symptoms of anxiety and depression. Methods: A secondary analysis of data from a randomized controlled trial that contrasted HED SMART (n = 101) against usual care (n = 134). Depressive and anxious symptoms were assessed using the Hospital Anxiety and Depression Scale (HADS) at baseline, 1 week and at 3 and 9 months post-intervention. Latent class growth analysis identified trajectories of depression and anxiety, and their sociodemographic and clinical predictors. Results: Symptoms of depression and anxiety over 12 months were characterized by two trajectories: low stable (depression: 55%; anxiety: 59%) with non-clinical levels of distress, and high stable (depression: 45%; anxiety: 41%) with clinical levels of distress. HED SMART predicted significant reductions in depression relative to usual care. A similar trend was noted for anxiety. Younger age, Chinese ethnicity, and more comorbidities were associated with persistent high depression. Younger age and shorter dialysis vintage was associated with persistent high anxiety. Conclusion: A brief self-management intervention designed to support behavioral change can also lead to significant reductions in symptoms of depression and may be of great value for younger HD patients shown to be at greater risk for persistent distress. Trial registration: ISRTN31434033
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Hemodialysis Self-management Intervention Randomized Trial (HED-SMART): A Practical Low-Intensity Intervention to Improve Adherence and Clinical Markers in Patients Receiving Hemodialysis
Background: Poor adherence to treatment is common in hemodialysis patients. However, effective interventions for adherence in this population are lacking. Small studies of behavioral interventions have yielded improvements, but clinical effectiveness and long-term effects are unclear.
Study Design: Multicenter parallel (1:1) design, blinded cluster-randomized controlled trial.
Setting & Participants: Patients undergoing maintenance hemodialysis enrolled in 14 dialysis centers.
Intervention: Dialysis shifts of eligible patients were randomly assigned to either an interactive and targeted self-management training program (HED-SMART; intervention; n = 134) or usual care (control; n = 101). HED-SMART, developed using the principles of problem solving and social learning theory, was delivered in a group format by health care professionals over 4 sessions.
Outcomes & Measurements: Serum potassium and phosphate concentrations, interdialytic weight gains (IDWGs), self-reported adherence, and self-management skills at 1 week, 3 months, and 9 months postintervention.
Results: 235 participants were enrolled in the study (response rate, 44.2%), and 82.1% completed the protocol. IDWG was significantly lowered across all 3 assessments relative to baseline (P < . 0.001) among patients randomly assigned to HED-SMART. In contrast, IDWG in controls showed no change except at 3 months, when it worsened significantly. Improvements in mineral markers were noted in the HED-SMART arm at 3 months (P < . 0.001) and in potassium concentrations (P < . 0.001) at 9 months. Phosphate concentrations improved in HED-SMART at 3 months (P = 0.03), but these effects were not maintained at 9 months postintervention. Significant differences between the arms were found for the secondary outcomes of self-reported adherence, self-management skills, and self-efficacy at all time points.
Limitations: Low proportion of patients with diabetes.
Conclusions: HED-SMART provides an effective and practical model for improving health in hemodialysis patients. The observed improvements in clinical markers and self-report adherence, if maintained at the longer follow-up, could significantly reduce end-stage renal disease-related complications. Given the feasibility of this kind of program, it has strong potential for supplementing usual care.
Trial Registration: Registered at ISRCTN with study number ISRCTN31434033
A direct-drive solution for Hydrogen supplied all-electric airplane
This paper present a solution for traction motor in ultra light motored (ULM) aircraft applications. A new All electric aircraft is here presented with a hydrogen supplied fuel-cell system and a direct-drive configuration for traction motor. A reverse brushless solution with a distributed winding high pole-pair motor is presented for a 60 kW continuous power solution. Materials and geometry have been analyzed with a goal of high torque density and high speed realization. Motor design key points and losses estimation in comparison with the experimental results will be presented
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The role of subjective cognitive complaints in self‑management among haemodialysis patients: a cross‑sectional study
Background
Subjective cognitive complaints refer to self-experienced difficulties with everyday cognitive tasks. Although there has been a fair amount of research on cognitive impairments and cognitive complaints in end-stage renal disease, the practical implications of these complaints remain unclear. The current study aims to examine the associations of cognitive complaints with sociodemographic and clinical variables, mood, as well as key patient-reported outcomes, i.e., self-efficacy, self-management skills, and treatment adherence.
Methods
A total of 305 haemodialysis patients (mean age = 53.97 years, 42.6% female) completed the Kidney Disease Quality of Life Cognitive Function subscale, a brief measure of cognitive complaints. The recommended cut-off point of 60 was used to identify probable cognitive impairment. Measures of self-efficacy, self-management skills (i.e., symptom coping, health monitoring, health service navigation), treatment adherence, and mood symptoms were also administered. Between-group comparisons and correlational analyses were performed to examine associations of cognitive complaints with sociodemographic, clinical, and health behaviour variables. Mediation analyses were also conducted to investigate the mediating role of self-efficacy on the relationship between cognitive complaints and treatment adherence.
Results
Nearly a quarter (23.0%) of haemodialysis patients reported cognitive complaints indicative of clinical impairments. Risk of probable impairments was higher for patients with hypertension, diabetes, those diagnosed with end-stage renal disease at an older age, and those with shorter time on dialysis. Subjective cognitive complaints (both rates of probable impairments as per cut-off and continuous scores) were significantly associated with lower disease and treatment self-efficacy, poorer self-management skills, lower treatment adherence, as well as higher symptoms of distress. Mediation analysis indicated that treatment self-efficacy mediated the relationship between cognitive complaints and treatment adherence.
Conclusions
The current study demonstrated the clinical characteristics of haemodialysis patients who report cognitive complaints indicative of probable cognitive impairments and showed the associations of these complaints with self-management outcomes. Future studies should adopt more comprehensive measures of cognitive complaints and longitudinal designs to confirm the current findings
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The combined diabetes and renal control trial (C-DIRECT) - a feasibility randomised controlled trial to evaluate outcomes in multi-morbid patients with diabetes and on dialysis using a mixed methods approach
Background: This cluster randomised controlled trial set out to investigate the feasibility and acceptability of the “Combined Diabetes and Renal Control Trial” (C-DIRECT) intervention, a nurse-led intervention based on motivational interviewing and self-management in patients with coexisting end stage renal diseases and diabetes mellitus (DM ESRD). Its efficacy to improve glycaemic control, as well as psychosocial and self-care outcomes were also evaluated as secondary outcomes.
Methods: An assessor-blinded, clustered randomised-controlled trial was conducted with 44 haemodialysis patients with DM ESRD and ≥ 8% glycated haemoglobin (HbA1c), in dialysis centres across Singapore. Patients were randomised according to dialysis shifts. 20 patients were assigned to intervention and 24 were in usual care. The C-DIRECT intervention consisted of three weekly chair-side sessions delivered by diabetes specialist nurses. Data on recruitment, randomisation, and retention, and secondary outcomes such as clinical endpoints, emotional distress, adherence, and self-management skills measures were obtained at baseline and at 12 weeks follow-up. A qualitative evaluation using interviews was conducted at the end of the trial.
Results: Of the 44 recruited at baseline, 42 patients were evaluated at follow-up. One patient died, and one discontinued the study due to deteriorating health. Recruitment, retention, and acceptability rates of C-DIRECT were generally satisfactory HbA1c levels decreased in both groups, but C-DIRECT had more participants with HbA1c < 8% at follow up compared to usual care. Significant improvements in role limitations due to physical health were noted for C-DIRECT whereas levels remained stable in usual care. No statistically significant differences between groups were observed for other clinical markers and other patient-reported outcomes. There were no adverse effects.
Conclusions: The trial demonstrated satisfactory feasibility. A brief intervention delivered on bedside as part of routine dialysis care showed some benefits in glycaemic control and on QOL domain compared with usual care, although no effect was observed in other secondary outcomes. Further research is needed to design and assess interventions to promote diabetes self-management in socially vulnerable patients
Factors determining social participation in the first year after kidney transplantation: a prospective study
BACKGROUND: This study describes changes in social participation in the first year after kidney transplantation and examines the influence of clinical factors, health status, transplantation-related symptoms, and psychological characteristics on change in social participation. METHODS: A prospective study was performed on a cohort of primary kidney transplant recipients, transplanted between March 2002 and March 2003. Data on participation in obligatory activities (i.e., employment, education, household tasks) and leisure activities (i.e., volunteer work, assisting others, sports, clubs/associations, recreation, socializing, going out) were collected by in-home interviews (n=61) at 3 months (T1) and 1 year posttransplantation (T2). Analysis of covariance was performed. RESULTS: Data showed an increase in participation in obligatory activities and diversity of leisure participation between T1 and T2, although pre-end-stage renal disease level was not regained and differed from the general population. On T1, the majority of employed recipients were on sick leave, but returned to work on T2. Employment rate remained stable. An increase in obligatory participation was predicted by clinical factors (i.e., peritoneal dialysis, initial hospitalization), whereas change in leisure participation was related to serum albumin and cognitive capacity. No effects were found for type of donation, comorbidity, and renal function. CONCLUSIONS: We found that mainly clinical factors were associated with an increase in participation in society. Although health-status related factors and the psychological attribute self-efficacy may be related to recovery of social participation, their effect was outweighed by the strength of clinical predictors in multivariate analysis
Концепція реформування літературної освіти в середній школі (предмет – українська література)
This paper provides a technique that minimize the cruise drag (or maximize L/D) fora blended wing body transport with a number of constraints. The wing shape design isdone by splitting the problem into 2D airfoil design and 3D twist optimization with a frozenplanform. A 45% to 50% reduction of inviscid drag is nally obtained, with desired pitchingmoment. The results indicate that further improvement can be obtained by modifying theplanform and varying the camber more aggressively.QC 20121113NOVEMO
The Continuous Sample of Working Lives: improving its representativeness
This paper studies the representativeness of the Continuous Sample of Working Lives (CSWL), a set of anonymized microdata containing information on individuals from Spanish Social Security records. We examine several CSWL waves (2005-2013) and show that it is not representative for the population with a pension income. We then develop a methodology to draw a large dataset from the CSWL that is much more representative of the retired population in terms of pension type, gender and age. This procedure also makes it possible for users to choose between goodness of fit and subsample size. In order to illustrate the practical significance of our methodology, the paper also contains an application in which we generate a large subsample distribution from the 2010 CSWL. The results are striking: with a very small reduction in the size of the original CSWL, we significantly reduce errors in estimating pension expenditure for 2010, with a p value greater or equal to 0.999
The State Socialist Mortality Syndrome
Death rates for working-age men in European state socialist countries deviated from general improvements in survival observed in the rest of Europe during the 20th century. The magnitude of structural labor force changes across countries correlates with lagged increases in death rates for men in the working ages. This pattern is consistent with a hypothesis that hyper-development of heavy industry and stagnation (even contraction) of the service sector created anomic conditions leading to unhealthy lifestyles and self-destructive behavior among men moving from primary-sector to secondary-sector occupations. Occupational contrasts within countries similarly show concentration of rising male death rates among blue collar workers. Collapse of state socialist systems produced rapid corrections in labor force structure after 1990, again correlated with a fading of the state socialist mortality syndrome in following decades
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