771 research outputs found

    The monitoring of induction motor starting transients with a view to early fault detection.

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    The aim of this work is to investigate the possibility of detecting faults in a 3 phase Induction motor by monitoring and analysing the transient line current waveform during the starting period. This is a particularly onerous time for the machine and the inter-relationships between parameters such as current, torque, speed and time are very complex. As a result two parallel paths of investigation have been followed, by methods of experimentation and computer simulation. Transient line current signals have been obtained from purpose built test rigs and these signals have been analysed in both the time and frequency domains. In order to assist with the comprehension of this data a sophisticated computer simulation of the induction motor during the starting period has also been developed. Computer simulation of the induction motor has been developed initially using the two and then three phase induction motor voltage equations which are solved by numerical integration. Using these techniques it has been possible to detect small degrees of fault level for both wound and cage rotor machines by analysing the line current waveform during the starting period. Good agreement has been found between the real and simulated data. A range of Digital Signal Processing techniques have been utilised to extract the components indicative of rotor faults. These techniques were at first wideband and highly numerically intensive, some originating from Speech Processing. The final processing techniques were far simpler and selected by analysis of the results from experimental data, both real and simulated

    How does sex influence multimorbidity? Secondary analysis of a large nationally representative dataset

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    Multimorbidity increases with age and is generally more common in women, but little is known about sex effects on the “typology” of multimorbidity. We have characterized multimorbidity in a large nationally representative primary care dataset in terms of sex in ten year age groups from 25 years to 75 years and over, in a cross-sectional analysis of multimorbidity type (physical-only, mental-only, mixed physical and mental; and commonest conditions) for 1,272,685 adults in Scotland. Our results show that women had more multimorbidity overall in every age group, which was most pronounced in the 45–54 years age group (women 26.5% vs. men 19.6%; difference 6.9 (95% CI 6.5 to 7.2). From the age of 45, physical-only multimorbidity was consistently more common in men, and physical-mental multimorbidity more common in women. The biggest difference in physical-mental multimorbidity was found in the 75 years and over group (women 30.9% vs. men 21.2%; difference 9.7 (95% CI 9.1 to 10.2). The commonest condition in women was depression until the age of 55 years, thereafter hypertension. In men, drugs misuse had the highest prevalence in those aged 25–34 years, depression for those aged 35–44 years, and hypertension for 45 years and over. Depression, pain, irritable bowel syndrome and thyroid disorders were more common in women than men across all age groups. We conclude that the higher overall prevalence of multimorbidity in women is mainly due to more mixed physical and mental health problems. The marked difference between the sexes over 75 years especially warrants further investigation

    Real-World Massage Therapy Produces Meaningful Effectiveness Signal for Primary Care Patients with Chronic Low Back Pain: Results of a Repeated Measures Cohort Study

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    Objective: While efficacy of massage and other nonpharmacological treatments for chronic low back pain is established, stakeholders have called for pragmatic studies of effectiveness in "real-world" primary health care. The Kentucky Pain Research and Outcomes Study evaluated massage impact on pain, disability, and health-related quality of life for primary care patients with chronic low back pain. We report effectiveness and feasibility results, and make comparisons with established minimal clinically important differences. Methods: Primary care providers referred eligible patients for 10 massage sessions with community practicing licensed massage therapists. Oswestry Disability Index and SF-36v2 measures obtained at baseline and postintervention at 12 and 24 weeks were analyzed with mixed linear models and Tukey's tests. Additional analyses examined clinically significant improvement and predictive patient characteristics. Results: Of 104 enrolled patients, 85 and 76 completed 12 and 24 weeks of data collection, respectively. Group means improved at 12 weeks for all outcomes and at 24 weeks for SF-36v2's Physical Component Summary and Bodily Pain Domain. Of those with clinically improved disability at 12 weeks, 75% were still clinically improved at 24 weeks ( P  < 0.01). For SF-36v2 Physical and Mental Component Summaries, 55.4% and 43.4%, respectively, showed clinically meaningful improvement at 12 weeks, 46.1% and 30.3% at 24 weeks. For Bodily Pain Domain, 49.4% were clinically improved at 12 weeks, 40% at 24 weeks. Adults older than age 49 years had better pain and disability outcomes than younger adults. Conclusions: Results provide a meaningful signal of massage effect for primary care patients with chronic low back pain and call for further research in practice settings using pragmatic designs with control groups

    An examination of the perceived impact of a continuing interprofessional education experience on opiate prescribing practices

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    Chronic pain is increasingly recognized as a public health problem. We assessed the effectiveness of a multi-modal, interprofessional educational approach aimed at empowering healthcare professionals to make deliberative changes, especially in opiate prescribing practices. Education activities included enduring webcasts, regional interprofessional roundtable events, and state-level conference presentations within targeted Kentucky and West Virginia regions of the United States. Over 1,000 participants accessed the various activities. For the live events, the largest groups reached included nurses (38.1%), nurse practitioners (31.2%), and physicians (22.1%). In addition to our reach, higher levels of educational effectiveness were measured, specifically, learner’s intentions to change practice patterns, confidence in meeting patient’s needs, and knowledge of pain management guidelines. The majority of the conference (58%) and roundtable (69%) participants stated they intend to make a practice change in one or more areas of chronic pain patient management in post-event evaluation. Differences in pre- and post-activity responses on the measures of confidence and knowledge, with additional comparison to a control population who were not in attendance, were analyzed using non-parametric tests of significance. While neither activity produced significant changes in confidence from pre-activity, participants were more confident post-activity than their control group peers. There were significant changes in knowledge for both live event and webcast participants. Impactful chronic pain continuing the education that emphasizes collaborative care is greatly needed; these results show that the approaches taken here can impact learner’s knowledge and confidence, and hold potential for creating change in how opioid prescribing is managed

    Applying genetic algorithms to multi-objective land use planning.

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    This paper explores the application of multi-objective genetic algorithms (mGAs) to rural land-use planning, a spatial allocation problem. Two mGAs are proposed. Both share an underlying structure of: fitness assignment using Pareto-dominance ranking, niche induction and an individual replacement strategy. They are differentiated by their representations: a fixed-length genotype composed of genes that map directly to a land parcel's use, and a variable-length, order-dependent representation making allocations indirectly via a greedy algorithm. The latter representation requires additional breeding operators to be defined and post-processing of the genotype structure, to identify and remove duplicate genotypes. The two mGAs are compared on a real land-use planning problem, and the strengths and weaknesses of the underlying framework - and of each representation - are identified

    Behavioral profiling of multiple pairs of rats selectively bred for high and low alcohol intake using the MCSF test

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    Genetic aspects of alcoholism have been modeled using rats selectively bred for extremes of alcohol preference and voluntary alcohol intake. These lines show similar alcohol drinking phenotypes but have different genetic and environmental backgrounds and may therefore display diverse behavioral traits as seen in human alcoholics. The multivariate concentric square field™ (MCSF) test is designed to provoke exploration and behaviors associated with risk assessment, risk taking and shelter seeking in a novel environment. The aim was to use the MCSF to characterize behavioral profiles in rat lines from selective breeding programs in the United States (P/NP, HAD1/LAD1, HAD2/LAD2), Italy (sP/sNP) and Finland (AA/ANA). The open field and elevated plus maze tests were used as reference tests. There were substantial differences within some of the pairs of selectively bred rat lines as well as between all alcohol-preferring rats. The most pronounced differences within the pairs of lines were between AA and ANA rats and between sP and sNP rats followed by intermediate differences between P and NP rats and minor differences comparing HAD and LAD rats. Among all preferring lines, P, HAD1 and HAD2 rats shared similar behavioral profiles, while AA and sP rats were quite different from each other and the others. No single trait appeared to form a common 'pathway' associated with a high alcohol drinking phenotype among all of the alcohol-preferring lines of rats. The marked behavioral differences found in the different alcohol-preferring lines may mimic the heterogeneity observed among human alcoholic subtypes

    Do patients have worse outcomes in heart failure than in cancer? A primary care-based cohort study with 10-year follow-up in Scotland

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    Aims: To evaluate whether the survival rates of patients with heart failure (HF) in the community are better than those with a diagnosis of the 4 most common cancers in men and women in a contemporary primary care cohort in Scotland. Methods and Results: The data were obtained from the Primary Care Clinical Informatics Unit from a database of 1.75 million people registered with 393 general practices in Scotland. Sex-specific survival modeling was undertaken using Cox proportional hazards models, adjusted for potential confounders. A total of 56,658 patients were eligible to be included in the study with 147,938 person years follow up (median follow up 2.04 years). In men, heart failure (reference group; 5yrs survival 37.7%) had worse mortality outcomes than patients with prostate cancer (HR 0.61, 95%CI 0.57-0.65; 5yrs survival 49.0%), and bladder cancer (HR 0.88, 95%CI 0.81-0.96; 5yrs survival 36.5%), but better than lung cancer (HR 3.86, 95%CI 3.65-4.07; 5yrs survival 2.8%) and colorectal cancer (HR 1.23 95%CI 1.16-1.31; 5 yrs survival 25.9%). In women, patients with HF (reference group; 5yrs survival 31.9%) had worse mortality outcomes than patients with breast cancer (HR 0.55 95%CI 0.51-0.59; 5yrs survival 61.0%), but better outcomes than lung cancer (HR 3.82, 95%CI 3.60-4.05; 5yrs survival 3.6%), ovarian cancer (HR 1.98, 95%CI 1.80-2.17; 5yrs survival 19%) and colorectal cancer (HR 1.21, 95%CI 1.13-1.29; 5yrs survival 28.4%). Conclusions: Despite advances in management, heart failure remains as ‘malignant’ as some of the common cancers in both men and women

    Effects of Bladder Training and/or Tolterodine in Female Patients with Overactive Bladder Syndrome: A Prospective, Randomized Study

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    We compared the effects of bladder training and/or tolterodine as first line treatment in female patients with overactive bladder (OAB). One hundred and thirty-nine female patients with OAB were randomized to treatment with bladder training (BT), tolterodine (To, 2 mg twice daily) or both (Co) for 12 weeks. Treatment efficacy was measured by micturition diary, urgency scores and patients' subjective assessment of their bladder condition. Mean frequency and nocturia significantly decreased in all treatment groups, declining 25.9% and 56.1%, respectively, in the BT group; 30.2% and 65.4%, respectively, in the To group; and 33.5% and 66.3%, respectively in the Co group (p<0.05 for each). The decrease in frequency was significantly greater in the Co group than in the BT group (p<0.05). Mean urgency score decreased by 44.8%, 62.2% and 60.2% in the BT, To, and Co groups, respectively, and the improvement was significantly greater in the To and Co groups than in the BT group (p<0.05 for each). Although BT, To and their combination were all effective in controlling OAB symptoms, combination therapy was more effective than either method alone. Tolterodine alone may be instituted as a first-line therapy, but may be more effective when combined with bladder training
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