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Sample records for robust randomised controlled

  1. Robust Adaptive Control

    NASA Technical Reports Server (NTRS)

    Narendra, K. S.; Annaswamy, A. M.

    1985-01-01

    Several concepts and results in robust adaptive control are are discussed and is organized in three parts. The first part surveys existing algorithms. Different formulations of the problem and theoretical solutions that have been suggested are reviewed here. The second part contains new results related to the role of persistent excitation in robust adaptive systems and the use of hybrid control to improve robustness. In the third part promising new areas for future research are suggested which combine different approaches currently known.

  2. Robust Control Systems.

    DTIC Science & Technology

    1981-12-01

    106 A. 13 XSU ......................................... 108 A.14 DDTCON...................................... 108 A.15 DKFTR...operation is preserved. Although some papers (Refs 6 and 13 ) deal with robustness only in regard to parameter variations within the basic controlled...since these can ofter be neglected in actual implementation, a constant-gain time 13 ........................................ invariant solution with

  3. Razors versus clippers. A randomised controlled trial.

    PubMed

    Taylor, Tracy; Tanner, Judith

    2005-12-01

    The purpose of this randomised controlled trial was to determine if patients showed a preference for preoperative hair removal with razors or clippers and to identify if one method was associated with more trauma or postoperative infections. The trial took place in a day surgery unit with patients who were having a range of surgical procedures including hernias and varicose veins. This study was sponsored by an award from the NATN/3M Clinical Fellowship.

  4. Robust Control Feedback and Learning

    DTIC Science & Technology

    2002-11-30

    98-1-0026 5b. GRANT NUMBER Robust Control, Feedback and Learning F49620-98-1-0026 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT NUMBER Michael G...Standard Form 298 (Rev. 8-98) Prescribed by ANSI Std. Z39.18 Final Report: ROBUST CONTROL FEEDBACK AND LEARNING AFOSR Grant F49620-98-1-0026 October 1...Philadelphia, PA, 2000. [16] M. G. Safonov. Recent advances in robust control, feedback and learning . In S. 0. R. Moheimani, editor, Perspectives in Robust

  5. The Hawthorne Effect: a randomised, controlled trial

    PubMed Central

    McCarney, Rob; Warner, James; Iliffe, Steve; van Haselen, Robbert; Griffin, Mark; Fisher, Peter

    2007-01-01

    Background The 'Hawthorne Effect' may be an important factor affecting the generalisability of clinical research to routine practice, but has been little studied. Hawthorne Effects have been reported in previous clinical trials in dementia but to our knowledge, no attempt has been made to quantify them. Our aim was to compare minimal follow-up to intensive follow-up in participants in a placebo controlled trial of Ginkgo biloba for treating mild-moderate dementia. Methods Participants in a dementia trial were randomised to intensive follow-up (with comprehensive assessment visits at baseline and two, four and six months post randomisation) or minimal follow-up (with an abbreviated assessment at baseline and a full assessment at six months). Our primary outcomes were cognitive functioning (ADAS-Cog) and participant and carer-rated quality of life (QOL-AD). Results We recruited 176 participants, mainly through general practices. The main analysis was based on Intention to treat (ITT), with available data. In the ANCOVA model with baseline score as a co-variate, follow-up group had a significant effect on outcome at six months on the ADAS-Cog score (n = 140; mean difference = -2.018; 95%CI -3.914, -0.121; p = 0.037 favouring the intensive follow-up group), and on participant-rated quality of life score (n = 142; mean difference = -1.382; 95%CI -2.642, -0.122; p = 0.032 favouring minimal follow-up group). There was no significant difference on carer quality of life. Conclusion We found that more intensive follow-up of individuals in a placebo-controlled clinical trial of Ginkgo biloba for treating mild-moderate dementia resulted in a better outcome than minimal follow-up, as measured by their cognitive functioning. Trial registration Current controlled trials: ISRCTN45577048 PMID:17608932

  6. Robust controls with structured perturbations

    NASA Technical Reports Server (NTRS)

    Keel, Leehyun

    1993-01-01

    This final report summarizes the recent results obtained by the principal investigator and his coworkers on the robust stability and control of systems containing parametric uncertainty. The starting point is a generalization of Kharitonov's theorem obtained in 1989, and its generalization to the multilinear case, the singling out of extremal stability subsets, and other ramifications now constitutes an extensive and coherent theory of robust parametric stability that is summarized in the results contained here.

  7. Writing to patients: a randomised controlled trial.

    PubMed

    O'Reilly, Máire; Cahill, Mary R; Perry, Ivan J

    2006-01-01

    It has been suggested that consultants should consider writing directly to patients with a summary of their outpatient consultation. In a controlled trial involving consecutive new referrals to a haematology outpatient clinic, we randomised patients to receive either a personal letter from their consultant summarising their consultation (n = 77) or a brief note thanking them for attending the clinic (n = 73). Patients were assessed for recall of and satisfaction with the consultation by a single independent observer, using standardised methods. At the second visit to outpatients, the patients' median percentage recall of items discussed during the consultation was 67% (IQ range 50-80%) in the intervention group, versus 57% (IQ range 43-76%) in the control group (p = 0.3). Strongly positive views on the personal letter were expressed by patients and referring clinicians. The findings suggest that although personal letters do not substantially improve recall of the clinical encounter, they are feasible, highly valued by patients and acceptable to referring clinicians.

  8. Robust flight control of rotorcraft

    NASA Astrophysics Data System (ADS)

    Pechner, Adam Daniel

    With recent design improvement in fixed wing aircraft, there has been a considerable interest in the design of robust flight control systems to compensate for the inherent instability necessary to achieve desired performance. Such systems are designed for maximum available retention of stability and performance in the presence of significant vehicle damage or system failure. The rotorcraft industry has shown similar interest in adopting these reconfigurable flight control schemes specifically because of their ability to reject disturbance inputs and provide a significant amount of robustness for all but the most catastrophic of situations. The research summarized herein focuses on the extension of the pseudo-sliding mode control design procedure interpreted in the frequency domain. Application of the technique is employed and simulated on two well known helicopters, a simplified model of a hovering Sikorsky S-61 and the military's Black Hawk UH-60A also produced by Sikorsky. The Sikorsky helicopter model details are readily available and was chosen because it can be limited to pitch and roll motion reducing the number of degrees of freedom and yet contains two degrees of freedom, which is the minimum requirement in proving the validity of the pseudo-sliding control technique. The full order model of a hovering Black Hawk system was included both as a comparison to the S-61 helicopter design system and as a means to demonstrate the scaleability and effectiveness of the control technique on sophisticated systems where design robustness is of critical concern.

  9. Relevance of randomised controlled trials in oncology.

    PubMed

    Tannock, Ian F; Amir, Eitan; Booth, Christopher M; Niraula, Saroj; Ocana, Alberto; Seruga, Bostjan; Templeton, Arnoud J; Vera-Badillo, Francisco

    2016-12-01

    Well-designed randomised controlled trials (RCTs) can prevent bias in the comparison of treatments and provide a sound basis for changes in clinical practice. However, the design and reporting of many RCTs can render their results of little relevance to clinical practice. In this Personal View, we discuss the limitations of RCT data and suggest some ways to improve the clinical relevance of RCTs in the everyday management of patients with cancer. RCTs should ask questions of clinical rather than commercial interest, avoid non-validated surrogate endpoints in registration trials, and have entry criteria that allow inclusion of all patients who are fit to receive treatment. Furthermore, RCTs should be reported with complete accounting of frequency and management of toxicities, and with strict guidelines to ensure freedom from bias. Premature reporting of results should be avoided. The bar for clinical benefit should be raised for drug registration, which should require publication and review of mature data from RCTs, post-marketing health outcome studies, and value-based pricing.

  10. Robust control with structured perturbations

    NASA Technical Reports Server (NTRS)

    Keel, Leehyun

    1988-01-01

    Two important problems in the area of control systems design and analysis are discussed. The first is the robust stability using characteristic polynomial, which is treated first in characteristic polynomial coefficient space with respect to perturbations in the coefficients of the characteristic polynomial, and then for a control system containing perturbed parameters in the transfer function description of the plant. In coefficient space, a simple expression is first given for the l(sup 2) stability margin for both monic and non-monic cases. Following this, a method is extended to reveal much larger stability region. This result has been extended to the parameter space so that one can determine the stability margin, in terms of ranges of parameter variations, of the closed loop system when the nominal stabilizing controller is given. The stability margin can be enlarged by a choice of better stabilizing controller. The second problem describes the lower order stabilization problem, the motivation of the problem is as follows. Even though the wide range of stabilizing controller design methodologies is available in both the state space and transfer function domains, all of these methods produce unnecessarily high order controllers. In practice, the stabilization is only one of many requirements to be satisfied. Therefore, if the order of a stabilizing controller is excessively high, one can normally expect to have a even higher order controller on the completion of design such as inclusion of dynamic response requirements, etc. Therefore, it is reasonable to have a lowest possible order stabilizing controller first and then adjust the controller to meet additional requirements. The algorithm for designing a lower order stabilizing controller is given. The algorithm does not necessarily produce the minimum order controller; however, the algorithm is theoretically logical and some simulation results show that the algorithm works in general.

  11. Randomised controlled trial of mesalazine in IBS

    PubMed Central

    Barbara, Giovanni; Cremon, Cesare; Annese, Vito; Basilisco, Guido; Bazzoli, Franco; Bellini, Massimo; Benedetti, Antonio; Benini, Luigi; Bossa, Fabrizio; Buldrini, Paola; Cicala, Michele; Cuomo, Rosario; Germanà, Bastianello; Molteni, Paola; Neri, Matteo; Rodi, Marcello; Saggioro, Alfredo; Scribano, Maria Lia; Vecchi, Maurizio; Zoli, Giorgio; Corinaldesi, Roberto; Stanghellini, Vincenzo

    2016-01-01

    Objective Low-grade intestinal inflammation plays a role in the pathophysiology of IBS. In this trial, we aimed at evaluating the efficacy and safety of mesalazine in patients with IBS. Design We conducted a phase 3, multicentre, tertiary setting, randomised, double-blind, placebo-controlled trial in patients with Rome III confirmed IBS. Patients were randomly assigned to either mesalazine, 800 mg, or placebo, three times daily for 12 weeks, and were followed for additional 12 weeks. The primary efficacy endpoint was satisfactory relief of abdominal pain/discomfort for at least half of the weeks of the treatment period. The key secondary endpoint was satisfactory relief of overall IBS symptoms. Supportive analyses were also performed classifying as responders patients with a percentage of affirmative answers of at least 75% or >75% of time. Results A total of 185 patients with IBS were enrolled from 21 centres. For the primary endpoint, the responder patients were 68.6% in the mesalazine group versus 67.4% in the placebo group (p=0.870; 95% CI −12.8 to 15.1). In explorative analyses, with the 75% rule or >75% rule, the percentage of responders was greater in the mesalazine group with a difference over placebo of 11.6% (p=0.115; 95% CI −2.7% to 26.0%) and 5.9% (p=0.404; 95% CI −7.8% to 19.4%), respectively, although these differences were not significant. For the key secondary endpoint, overall symptoms improved in the mesalazine group and reached a significant difference of 15.1% versus placebo (p=0.032; 95% CI 1.5% to 28.7%) with the >75% rule. Conclusions Mesalazine treatment was not superior than placebo on the study primary endpoint. However, a subgroup of patients with IBS showed a sustained therapy response and benefits from a mesalazine therapy. Trial registration number ClincialTrials.gov number, NCT00626288. PMID:25533646

  12. Robust Fixed-Structure Controller Synthesis

    NASA Technical Reports Server (NTRS)

    Corrado, Joseph R.; Haddad, Wassim M.; Gupta, Kajal (Technical Monitor)

    2000-01-01

    The ability to develop an integrated control system design methodology for robust high performance controllers satisfying multiple design criteria and real world hardware constraints constitutes a challenging task. The increasingly stringent performance specifications required for controlling such systems necessitates a trade-off between controller complexity and robustness. The principle challenge of the minimal complexity robust control design is to arrive at a tractable control design formulation in spite of the extreme complexity of such systems. Hence, design of minimal complexitY robust controllers for systems in the face of modeling errors has been a major preoccupation of system and control theorists and practitioners for the past several decades.

  13. Outcomes in a Randomised Controlled Trial of Mathematics Tutoring

    ERIC Educational Resources Information Center

    Topping, K. J.; Miller, D.; Murray, P.; Henderson, S.; Fortuna, C.; Conlin, N.

    2011-01-01

    Background: Large-scale randomised controlled trials (RCT) are relatively rare in education. The present study was an attempt to scale up previous small peer tutoring projects, while investing only modestly in continuing professional development for teachers. Purpose: A two-year RCT of peer tutoring in mathematics was undertaken in one local…

  14. Robust Controller Design for Hemispherical Resonator Gyroscope

    DTIC Science & Technology

    2011-11-01

    f v Figure 1. Operating principle of HRG Robust Controller Design for Hemispherical Resonator Gyroscope Chul Hyun1), Byung ...Petersburg, Russia.: 26-34 4) Chul Hyun. 2011. Design of Robust Digital Controller for Hemispherical Resonator Gyroscopes, Ph.D. dissertation, Seoul

  15. Robust Multiobjective Controllability of Complex Neuronal Networks.

    PubMed

    Tang, Yang; Gao, Huijun; Du, Wei; Lu, Jianquan; Vasilakos, Athanasios V; Kurths, Jurgen

    2016-01-01

    This paper addresses robust multiobjective identification of driver nodes in the neuronal network of a cat's brain, in which uncertainties in determination of driver nodes and control gains are considered. A framework for robust multiobjective controllability is proposed by introducing interval uncertainties and optimization algorithms. By appropriate definitions of robust multiobjective controllability, a robust nondominated sorting adaptive differential evolution (NSJaDE) is presented by means of the nondominated sorting mechanism and the adaptive differential evolution (JaDE). The simulation experimental results illustrate the satisfactory performance of NSJaDE for robust multiobjective controllability, in comparison with six statistical methods and two multiobjective evolutionary algorithms (MOEAs): nondominated sorting genetic algorithms II (NSGA-II) and nondominated sorting composite differential evolution. It is revealed that the existence of uncertainties in choosing driver nodes and designing control gains heavily affects the controllability of neuronal networks. We also unveil that driver nodes play a more drastic role than control gains in robust controllability. The developed NSJaDE and obtained results will shed light on the understanding of robustness in controlling realistic complex networks such as transportation networks, power grid networks, biological networks, etc.

  16. Robust nonlinear control of vectored thrust aircraft

    NASA Technical Reports Server (NTRS)

    Doyle, John C.; Murray, Richard; Morris, John

    1993-01-01

    An interdisciplinary program in robust control for nonlinear systems with applications to a variety of engineering problems is outlined. Major emphasis will be placed on flight control, with both experimental and analytical studies. This program builds on recent new results in control theory for stability, stabilization, robust stability, robust performance, synthesis, and model reduction in a unified framework using Linear Fractional Transformations (LFT's), Linear Matrix Inequalities (LMI's), and the structured singular value micron. Most of these new advances have been accomplished by the Caltech controls group independently or in collaboration with researchers in other institutions. These recent results offer a new and remarkably unified framework for all aspects of robust control, but what is particularly important for this program is that they also have important implications for system identification and control of nonlinear systems. This combines well with Caltech's expertise in nonlinear control theory, both in geometric methods and methods for systems with constraints and saturations.

  17. Research in robust control for hypersonic aircraft

    NASA Technical Reports Server (NTRS)

    Calise, A. J.

    1993-01-01

    The research during the second reporting period has focused on robust control design for hypersonic vehicles. An already existing design for the Hypersonic Winged-Cone Configuration has been enhanced. Uncertainty models for the effects of propulsion system perturbations due to angle of attack variations, structural vibrations, and uncertainty in control effectiveness were developed. Using H(sub infinity) and mu-synthesis techniques, various control designs were performed in order to investigate the impact of these effects on achievable robust performance.

  18. Modeling and robust control of wind turbine

    NASA Astrophysics Data System (ADS)

    Gilev, Bogdan

    2016-12-01

    In this paper a model of a wind turbine is evaluated, consisting of: wind speed model, mechanical and electrical model of generator and tower oscillation model. This model is linearized around of a nominal point. By using the linear model with uncertainties is synthesized a uncertain model. By using the uncertain model and robust control theory is developed a robust controller, which provide mode of stabilizing the rotor frequency and damping the tower oscillations. Finally is simulated work of nonlinear system and robust controller

  19. Robust lateral control of highway vehicles

    SciTech Connect

    Byrne, R.H.; Abdallah, C.

    1994-08-01

    Vehicle lateral dynamics are affected by vehicle mass, longitudinal velocity, vehicle inertia, and the cornering stiffness of the tires. All of these parameters are subject to variation, even over the course of a single trip. Therefore, a practical lateral control system must guarantee stability, and hopefully ride comfort, over a wide range of parameter changes. This paper describes a robust controller which theoretically guarantees stability over a wide range of parameter changes. The robust controller is designed using a frequency domain transfer function approach. An uncertainty band in the frequency domain is determined using simulations over the range of expected parameter variations. Based on this bound, a robust controller is designed by solving the Nevanlinna-Pick interpolation problem. The performance of the robust controller is then evaluated over the range of parameter variations through simulations.

  20. Experimental Robust Control of Structural Acoustic Radiation

    NASA Technical Reports Server (NTRS)

    Cox, David E.; Gibbs, Gary P.; Clark, Robert L.; Vipperman, Jeffrey S.

    1998-01-01

    This work addresses the design and application of robust controllers for structural acoustic control. Both simulation and experimental results are presented. H(infinity) and mu-synthesis design methods were used to design feedback controllers which minimize power radiated from a panel while avoiding instability due to unmodeled dynamics. Specifically, high order structural modes which couple strongly to the actuator-sensor path were poorly modeled. This model error was analytically bounded with an uncertainty model, which allowed controllers to be designed without artificial limits on control effort. It is found that robust control methods provide the control designer with physically meaningful parameters with which to tune control designs and can be very useful in determining limits of performance. Experimental results also showed, however, poor robustness properties for control designs with ad-hoc uncertainty models. The importance of quantifying and bounding model errors is discussed.

  1. Applications of robust control theory - Educational implications

    NASA Technical Reports Server (NTRS)

    Dorato, P.; Yedavalli, R. K.

    1992-01-01

    A survey is made of applications of robust control theory to problems of flight control, control of flexible space structures, and engine control which have appeared in recent conferences and journals. An analysis is made of which theoretical techniques are most commonly used and what implications this has for graduate and undergraduate education in aerospace engineering.

  2. Robust Fuzzy Controllers Using FPGAs

    NASA Technical Reports Server (NTRS)

    Monroe, Author Gene S., Jr.

    2007-01-01

    Electro-mechanical device controllers typically come in one of three forms, proportional (P), Proportional Derivative (PD), and Proportional Integral Derivative (PID). Two methods of control are discussed in this paper; they are (1) the classical technique that requires an in-depth mathematical use of poles and zeros, and (2) the fuzzy logic (FL) technique that is similar to the way humans think and make decisions. FL controllers are used in multiple industries; examples include control engineering, computer vision, pattern recognition, statistics, and data analysis. Presented is a study on the development of a PD motor controller written in very high speed hardware description language (VHDL), and implemented in FL. Four distinct abstractions compose the FL controller, they are the fuzzifier, the rule-base, the fuzzy inference system (FIS), and the defuzzifier. FL is similar to, but different from, Boolean logic; where the output value may be equal to 0 or 1, but it could also be equal to any decimal value between them. This controller is unique because of its VHDL implementation, which uses integer mathematics. To compensate for VHDL's inability to synthesis floating point numbers, a scale factor equal to 10(sup (N/4) is utilized; where N is equal to data word size. The scaling factor shifts the decimal digits to the left of the decimal point for increased precision. PD controllers are ideal for use with servo motors, where position control is effective. This paper discusses control methods for motion-base platforms where a constant velocity equivalent to a spectral resolution of 0.25 cm(exp -1) is required; however, the control capability of this controller extends to various other platforms.

  3. [Psychotherapy in bipolar disorders -- randomised controlled trials of treatment efficacy].

    PubMed

    Rode, Sibylle; Wagner, Petra; Bräunig, Peter

    2006-03-01

    On the basis of a vulnerability-stress-model psycho-educative, cognitive-behavioural, family-oriented and interpersonal approaches of psychotherapy for bipolar disorders are described. This is followed by a review of randomised controlled trials investigating the treatment efficacy of psychotherapeutic interventions. These studies show positive results particularly for psychoeducation, cognitive-behavioural therapy and family-oriented therapy. Finally, it is discussed in which respects evidence for the successful implementation of psychotherapy is still missing and why it is so important to move towards manualized psychotherapeutic programs.

  4. Robust Reachability of Boolean Control Networks.

    PubMed

    Li, Fangfei; Tang, Yang

    2016-04-20

    Boolean networks serve a powerful tool in analysis of genetic regulatory networks since it emphasizes the fundamental principles and establishes a nature framework for capturing the dynamics of regulation of cellular states. In this paper, the robust reachability of Boolean control networks is investigated by means of semi-tensor product. Necessary and sufficient conditions for the robust reachability of Boolean control networks are provided, in which control inputs relying on disturbances or not are considered, respectively. Besides, the corresponding control algorithms are developed for these two cases. A reduced model of the lac operon in the Escherichia coli is presented to show the effectiveness of the presented results.

  5. A Randomised Controlled Trial of complete denture impression materials

    PubMed Central

    Hyde, T.P.; Craddock, H.L.; Gray, J.C.; Pavitt, S.H.; Hulme, C.; Godfrey, M.; Fernandez, C.; Navarro-Coy, N.; Dillon, S.; Wright, J.; Brown, S.; Dukanovic, G.; Brunton, P.A.

    2014-01-01

    Objectives There is continuing demand for non-implant prosthodontic treatment and yet there is a paucity of high quality Randomised Controlled Trial (RCT) evidence for best practice. The aim of this research was to provide evidence for best practice in prosthodontic impressions by comparing two impression materials in a double-blind, randomised, crossover, controlled, clinical trial. Methods Eighty-five patients were recruited, using published eligibility criteria, to the trial at Leeds Dental Institute, UK. Each patient received two sets of dentures; made using either alginate or silicone impressions. Randomisations determined the order of assessment and order of impressions. The primary outcome was patient blinded preference for unadjusted dentures. Secondary outcomes were patient preference for the adjusted dentures, rating of comfort, stability and chewing efficiency, experience of each impression, and an OHIP-EDENT questionnaire. Results Seventy-eight (91.8%) patients completed the primary assessment. 53(67.9%) patients preferred dentures made from silicone impressions while 14(17.9%) preferred alginate impressions. 4(5.1%) patients found both dentures equally satisfactory and 7 (9.0%) found both equally unsatisfactory. There was a 50% difference in preference rates (in favour of silicone) (95%CI 32.7–67.3%, p < 0.0001). Conclusion There is significant evidence that dentures made from silicone impressions were preferred by patients. Clinical significance Given the strength of the clinical findings within this paper, dentists should consider choosing silicone rather than alginate as their material of choice for secondary impressions for complete dentures. Trial Registration: ISRCTN 01528038.

 This article forms part of a project for which the author (TPH) won the Senior Clinical Unilever Hatton Award of the International Assocation for Dental Research, Capetown, South Africa, June 2014. PMID:24995473

  6. Robust control for large space antennas

    NASA Technical Reports Server (NTRS)

    Barrett, M. F.

    1987-01-01

    A brief description of program objectives and the space based radar application is given. General characteristics of the 100 m diameter reflector spacecraft are described along with the intended mission and associated requirements, and dynamic characteristics relevant to that mission. Preliminary control analyses are carried out for the critical rapid slew and settle maneuver to establish feedback control requirements and fundamental limitations in meeting those requirements with control hardware for a baseline reaction control system (RCS) jet placement assumed for the open loop bang-bang slew limitations. Control moment gyros (CMGs), angular position sensors, and linear translation sensors are placed for feedback control. Control laws are designed for the improved sensor and actuator placement and evaluated for performance and robustness to unstructured model uncertainty. The robustness of the control design is assessed with respect to modal parameter uncertainty. Results of the control designs analyses are summarized, conclusions are drawn, and recommendations made for future studies.

  7. Improving venous ulcer healing: designing and reporting randomised controlled trials.

    PubMed

    Weller, Carolina D; McNeil, John; Evans, Sue; Reid, Christopher

    2010-02-01

    The randomised controlled trial (RCT) is often considered the gold standard for judging the benefits of treatments. The application of randomised controlled clinical trials to treatments of venous ulcer healing has lagged behind that of other areas of medicine. To interpret the results of an RCT, readers must understand a variety of aspects of their design, analysis and interpretation. Venous ulcer disease has a high prevalence and has a significant socioeconomic impact in most parts of the world. The management of venous ulcers causes a considerable strain on the health system and is likely to worsen in future. The multi-layer high compression system is described as the current gold standard for treating venous ulcers. A recent meta-analysis of bandaging systems found that multi-layer compression bandages appeared to be superior to single-layer bandages in promoting venous ulcer healing. However, it was noted that many of the studies had small sample sizes and the quality of research in the area was poor. The consolidating standards of reporting trials (CONSORT) statement can help clinicians to discern high-quality studies from ones of poorer quality. This paper discusses how CONSORT can help clinicians and researchers to design and report quality studies to contribute to evidence-based venous ulcer healing.

  8. Robustness of network controllability in cascading failure

    NASA Astrophysics Data System (ADS)

    Chen, Shi-Ming; Xu, Yun-Fei; Nie, Sen

    2017-04-01

    It is demonstrated that controlling complex networks in practice needs more inputs than that predicted by the structural controllability framework. Besides, considering the networks usually faces to the external or internal failure, we define parameters to evaluate the control cost and the variation of controllability after cascades, exploring the effect of number of control inputs on the controllability for random networks and scale-free networks in the process of cascading failure. For different topological networks, the results show that the robustness of controllability will be stronger through allocating different control inputs and edge capacity.

  9. Synthesis Methods for Robust Passification and Control

    NASA Technical Reports Server (NTRS)

    Kelkar, Atul G.; Joshi, Suresh M. (Technical Monitor)

    2000-01-01

    The research effort under this cooperative agreement has been essentially the continuation of the work from previous grants. The ongoing work has primarily focused on developing passivity-based control techniques for Linear Time-Invariant (LTI) systems. During this period, there has been a significant progress made in the area of passivity-based control of LTI systems and some preliminary results have also been obtained for nonlinear systems, as well. The prior work has addressed optimal control design for inherently passive as well as non- passive linear systems. For exploiting the robustness characteristics of passivity-based controllers the passification methodology was developed for LTI systems that are not inherently passive. Various methods of passification were first proposed in and further developed. The robustness of passification was addressed for multi-input multi-output (MIMO) systems for certain classes of uncertainties using frequency-domain methods. For MIMO systems, a state-space approach using Linear Matrix Inequality (LMI)-based formulation was presented, for passification of non-passive LTI systems. An LMI-based robust passification technique was presented for systems with redundant actuators and sensors. The redundancy in actuators and sensors was used effectively for robust passification using the LMI formulation. The passification was designed to be robust to an interval-type uncertainties in system parameters. The passification techniques were used to design a robust controller for Benchmark Active Control Technology wing under parametric uncertainties. The results on passive nonlinear systems, however, are very limited to date. Our recent work in this area was presented, wherein some stability results were obtained for passive nonlinear systems that are affine in control.

  10. Average-cost based robust structural control

    NASA Technical Reports Server (NTRS)

    Hagood, Nesbitt W.

    1993-01-01

    A method is presented for the synthesis of robust controllers for linear time invariant structural systems with parameterized uncertainty. The method involves minimizing quantities related to the quadratic cost (H2-norm) averaged over a set of systems described by real parameters such as natural frequencies and modal residues. Bounded average cost is shown to imply stability over the set of systems. Approximations for the exact average are derived and proposed as cost functionals. The properties of these approximate average cost functionals are established. The exact average and approximate average cost functionals are used to derive dynamic controllers which can provide stability robustness. The robustness properties of these controllers are demonstrated in illustrative numerical examples and tested in a simple SISO experiment on the MIT multi-point alignment testbed.

  11. Structurally robust control of complex networks

    NASA Astrophysics Data System (ADS)

    Nacher, Jose C.; Akutsu, Tatsuya

    2015-01-01

    Robust control theory has been successfully applied to numerous real-world problems using a small set of devices called controllers. However, the real systems represented by networks contain unreliable components and modern robust control engineering has not addressed the problem of structural changes on complex networks including scale-free topologies. Here, we introduce the concept of structurally robust control of complex networks and provide a concrete example using an algorithmic framework that is widely applied in engineering. The developed analytical tools, computer simulations, and real network analyses lead herein to the discovery that robust control can be achieved in scale-free networks with exactly the same order of controllers required in a standard nonrobust configuration by adjusting only the minimum degree. The presented methodology also addresses the probabilistic failure of links in real systems, such as neural synaptic unreliability in Caenorhabditis elegans, and suggests a new direction to pursue in studies of complex networks in which control theory has a role.

  12. Matlab as a robust control design tool

    NASA Technical Reports Server (NTRS)

    Gregory, Irene M.

    1994-01-01

    This presentation introduces Matlab as a tool used in flight control research. The example used to illustrate some of the capabilities of this software is a robust controller designed for a single stage to orbit air breathing vehicles's ascent to orbit. The global requirements of the controller are to stabilize the vehicle and follow a trajectory in the presence of atmospheric disturbances and strong dynamic coupling between airframe and propulsion.

  13. Robust Adaptive Control of Hypnosis During Anesthesia

    DTIC Science & Technology

    2007-11-02

    1 of 4 ROBUST ADAPTIVE CONTROL OF HYPNOSIS DURING ANESTHESIA Pascal Grieder1, Andrea Gentilini1, Manfred Morari1, Thomas W. Schnider2 1ETH Zentrum...A closed-loop controller for hypnosis was designed and validated on humans at our laboratory. The controller aims at regulat- ing the Bispectral Index...BIS) - a surro- gate measure of hypnosis derived from the electroencephalogram of the patient - with the volatile anesthetic isoflurane administered

  14. Robust control algorithms for Mars aerobraking

    NASA Astrophysics Data System (ADS)

    Shipley, Buford W., Jr.; Ward, Donald T.

    Four atmospheric guidance concepts have been adapted to control an interplanetary vehicle aerobraking in the Martian atmosphere. The first two offer improvements to the Analytic Predictor Corrector (APC) to increase its robustness to density variations. The second two are variations of a new Liapunov tracking exit phase algorithm, developed to guide the vehicle along a reference trajectory. These four new controllers are tested using a six degree of freedom computer simulation to evaluate their robustness. MARSGRAM is used to develop realistic atmospheres for the study. When square wave density pulses perturb the atmosphere all four controllers are successful. The algorithms are tested against atmospheres where the inbound and outbound density functions are different. Square wave density pulses are again used, but only for the outbound leg of the trajectory. Additionally, sine waves are used to perturb the density function. The new algorithms are found to be more robust than any previously tested and a Liapunov controller is selected as the most robust control algorithm overall examined.

  15. Real Time & Power Efficient Adaptive - Robust Control

    NASA Astrophysics Data System (ADS)

    Ioan Gliga, Lavinius; Constantin Mihai, Cosmin; Lupu, Ciprian; Popescu, Dumitru

    2017-01-01

    A design procedure for a control system suited for dynamic variable processes is presented in this paper. The proposed adaptive - robust control strategy considers both adaptive control advantages and robust control benefits. It estimates the degradation of the system’s performances due to the dynamic variation in the process and it then utilizes it to determine when the system must be adapted with a redesign of the robust controller. A single integral criterion is used for the identification of the process, and for the design of the control algorithm, which is expressed in direct form, through a cost function defined in the space of the parameters of both the process and the controller. For the minimization of this nonlinear function, an adequate mathematical programming minimization method is used. The theoretical approach presented in this paper was validated for a closed loop control system, simulated in an application developed in C. Because of the reduced number of operations, this method is suitable for implementation on fast processes. Due to its effectiveness, it increases the idle time of the CPU, thereby saving electrical energy.

  16. Robust blood-glucose control using Mathematica.

    PubMed

    Kovács, Levente; Paláncz, Béla; Benyó, Balázs; Török, László; Benyó, Zoltán

    2006-01-01

    A robust control design on frequency domain using Mathematica is presented for regularization of glucose level in type I diabetes persons under intensive care. The method originally proposed under Mathematica by Helton and Merino, --now with an improved disturbance rejection constraint inequality--is employed, using a three-state minimal patient model. The robustness of the resulted high-order linear controller is demonstrated by nonlinear closed loop simulation in state-space, in case of standard meal disturbances and is compared with H infinity design implemented with the mu-toolbox of Matlab. The controller designed with model parameters represented the most favorable plant dynamics from the point of view of control purposes, can operate properly even in case of parameter values of the worst-case scenario.

  17. Robust Stabilization Control for an Electric Bicycle

    NASA Astrophysics Data System (ADS)

    Kawamura, Takuro; Murakami, Toshiyuki

    Recently, bicycles have gained immense popularity because they have high mobility and are an environment-friendly means of transport. However, many people tend to avoid riding a bicycle because it is unstable. In order to solve this problem, stabilization control for a bicycle has been researched. The aim of this study is improvement of the robustness in stabilization control. To achieve this goal, control systems that use a camber angle disturbance observer (CADO) are proposed. Two kinds of CADOs are proposed in this paper, and the performances of these two observers are compared. The proposed control systems provide higher robustness than does the conventional method. The validity of the proposed methods is confirmed by the experimental results.

  18. Robust dynamic inversion control laws for aircraft control

    NASA Technical Reports Server (NTRS)

    Balas, Gary J.; Garrard, William L.; Reiner, Jakob

    1992-01-01

    Dynamic inversion is a technique for control law design in which feedback is used to simultaneously cancel system dynamics and achieve desired dynamic response characteristics. However, dynamic inversion control laws lack robustness to modeling errors if improperly designed. This paper examines a simple linear example, control of roll rate about the body axis of high performance aircraft, to illustrate some robustness problems which may occur with a simple dynamic inversion control law. The paper demonstrates how structured singular value synthesis techniques can be used to enhance the robustness properties of the dynamic inversion controller.

  19. Robust adaptive control of HVDC systems

    SciTech Connect

    Reeve, J.; Sultan, M. )

    1994-07-01

    The transient performance of an HVDC power system is highly dependent on the parameters of the current/voltage regulators of the converter controls. In order to better accommodate changes in system structure or dc operating conditions, this paper introduces a new adaptive control strategy. The advantages of automatic tuning for continuous fine tuning are combined with predetermined gain scheduling in order to achieve robustness for large disturbances. Examples are provided for a digitally simulated back-to-back dc system.

  20. Vegetarian diet in mild hypertension: a randomised controlled trial.

    PubMed Central

    Margetts, B M; Beilin, L J; Vandongen, R; Armstrong, B K

    1986-01-01

    In a randomised crossover trial 58 subjects aged 30-64 with mild untreated hypertension were allocated either to a control group eating a typical omnivorous diet or to one of two groups eating an ovolactovegetarian diet for one of two six week periods. A fall in systolic blood pressure of the order of 5 mm Hg occurred during the vegetarian diet periods, with a corresponding rise on resuming a meat diet. The main nutrient changes with the vegetarian diet included an increase in the ratio of polyunsaturated to saturated fats and intake of fibre, calcium, and magnesium and a decrease in the intake of protein and vitamin B12. There were no consistent changes in urinary sodium or potassium excretion or body weight. In untreated subjects with mild hypertension, changing to a vegetarian diet may bring about a worthwhile fall in systolic blood pressure. PMID:3026552

  1. Low Bandwidth Robust Controllers for Flight

    NASA Technical Reports Server (NTRS)

    Biezad, Daniel J.; Chou, Hwei-Lan

    1993-01-01

    Through throttle manipulations, engine thrust can be used for emergency flight control for multi-engine aircraft. Previous study by NASA Dryden has shown the use of throttles for emergency flight control to be very difficult. In general, manual fly-by-throttle is extremely difficult - with landing almost impossible, but control augmentation makes runway landings feasible. Flight path control using throttles-only to achieve safe emergency landing for a large jet transport airplane, Boeing 720, was investigated using Quantitative Feedback Theory (QFT). Results were compared to an augmented control developed in a previous simulation study. The control augmentation corrected the unsatisfactory open-loop characteristics by increasing system bandwidth and damping, but increasing the control bandwidth substantially proved very difficult. The augmented pitch control is robust under no or moderate turbulence. The augmented roll control is sensitive to configuration changes.

  2. Low bandwidth robust controllers for flight

    NASA Technical Reports Server (NTRS)

    Biezad, Daniel J.; Chou, Hwei-Lan

    1993-01-01

    Through throttle manipulations, engine thrust can be used for emergency flight control for multi-engine aircraft. Previous study by NASA Dryden has shown the use of throttles for emergency flight control to be very difficult. In general, manual fly-by-throttle is extremely difficult - with landing almost impossible, but control augmentation makes runway landings feasible. Flight path control using throttles-only to achieve safe emergency landing for a large jet transport airplane, Boeing 720, was investigated using Quantitative Feedback Theory (QFT). Results were compared to an augmented control developed in a previous simulation study. The control augmentation corrected the unsatisfactory open-loop characteristics by increasing system bandwidth and damping, but increasing the control bandwidth substantially proved very difficult. The augmented pitch control is robust under no or moderate turbulence. The augmented roll control is sensitive to configuration changes.

  3. Robust control technique for nuclear power plants

    SciTech Connect

    Murphy, G.V.; Bailey, J.M.

    1989-03-01

    This report summarizes the linear quadratic Guassian (LQG) design technique with loop transfer recovery (LQG/LTR) for design of control systems. The concepts of return ratio, return difference, inverse return difference, and singular values are summarized. The LQG/LTR design technique allows the synthesis of a robust control system. To illustrate the LQG/LTR technique, a linearized model of a simple process has been chosen. The process has three state variables, one input, and one output. Three control system design methods are compared: LQG, LQG/LTR, and a proportional plus integral controller (PI). 7 refs., 20 figs., 6 tabs.

  4. Robust Control Design for Flight Control

    DTIC Science & Technology

    1989-07-01

    to achieve desired performance over the full flight envelope when linear feedback is employed. Exact linearization methods [48] provide means for...designing nonlinear feedback laws which satisfy these requirements. However, exact linearization is not always compatible with control authority...specific situations. The most promising approaches appear to be those associated with methods of exact linearization . This procedure is based on some

  5. Optimal and robust control of transition

    NASA Technical Reports Server (NTRS)

    Bewley, T. R.; Agarwal, R.

    1996-01-01

    Optimal and robust control theories are used to determine feedback control rules that effectively stabilize a linearly unstable flow in a plane channel. Wall transpiration (unsteady blowing/suction) with zero net mass flux is used as the control. Control algorithms are considered that depend both on full flowfield information and on estimates of that flowfield based on wall skin-friction measurements only. The development of these control algorithms accounts for modeling errors and measurement noise in a rigorous fashion; these disturbances are considered in both a structured (Gaussian) and unstructured ('worst case') sense. The performance of these algorithms is analyzed in terms of the eigenmodes of the resulting controlled systems, and the sensitivity of individual eigenmodes to both control and observation is quantified.

  6. Robustness

    NASA Technical Reports Server (NTRS)

    Ryan, R.

    1993-01-01

    Robustness is a buzz word common to all newly proposed space systems design as well as many new commercial products. The image that one conjures up when the word appears is a 'Paul Bunyon' (lumberjack design), strong and hearty; healthy with margins in all aspects of the design. In actuality, robustness is much broader in scope than margins, including such factors as simplicity, redundancy, desensitization to parameter variations, control of parameter variations (environments flucation), and operational approaches. These must be traded with concepts, materials, and fabrication approaches against the criteria of performance, cost, and reliability. This includes manufacturing, assembly, processing, checkout, and operations. The design engineer or project chief is faced with finding ways and means to inculcate robustness into an operational design. First, however, be sure he understands the definition and goals of robustness. This paper will deal with these issues as well as the need for the requirement for robustness.

  7. Robust control of ionic polymer metal composites

    NASA Astrophysics Data System (ADS)

    Kang, Sunhyuk; Shin, Jongho; Kim, Seong Jun; Kim, H. Jin; Hyup Kim, Yong

    2007-12-01

    Ionic polymer-metal composites (IPMCs) have been considered for various applications due to their light weight, large bending, and low actuation voltage requirements. However, their response can be slow and vary widely, depending on various factors such as fabrication processes, water content, and contact conditions with the electrodes. In order to utilize their capability in various high-performance microelectromechanical systems, controllers need to address this uncertainty and non-repeatability while improving the response speed. In this work, we identified an empirical model for the dynamic relationship between the applied voltage and the IPMC beam deflection, which includes the uncertainties and variations of the response. Then, four types of controller were designed, and their performances were compared: a proportional-integral-derivative (PID) controller with optimized gains using a co-evolutionary algorithm, and three types of robust controller based on H_\\infty , H_\\infty with loop shaping, and μ-synthesis, respectively. Our results show that the robust control techniques can significantly improve the IPMC performance against non-repeatability or parametric uncertainties, in terms of the faster response and lower overshoot than the PID control, using lower actuation voltage.

  8. A multi-centre randomised controlled trial of rehabilitation aimed at improving outdoor mobility for people after stroke: Study protocol for a randomised controlled trial

    PubMed Central

    2012-01-01

    . Discussion This study protocol describes a pragmatic randomised controlled trial that will hopefully provide robust evidence of the benefit of outdoor mobility interventions after stroke for clinicians working in the community. The results will be available towards the end of 2012. Trial registration ISRCTN58683841 PMID:22721452

  9. Robust model predictive control of Wiener systems

    NASA Astrophysics Data System (ADS)

    Biagiola, S. I.; Figueroa, J. L.

    2011-03-01

    Block-oriented models (BOMs) have shown to be appealing and efficient as nonlinear representations for many applications. They are at the same time valid and simple models in a more extensive region than time-invariant linear models. In this work, Wiener models are considered. They are one of the most diffused BOMs, and their structure consists in a linear dynamics in cascade with a nonlinear static block. Particularly, the problem of control of these systems in the presence of uncertainty is treated. The proposed methodology makes use of a robust identification procedure in order to obtain a robust model to represent the uncertain system. This model is then employed to design a model predictive controller. The mathematical problem involved in the controller design is formulated in the context of the existing linear matrix inequalities (LMI) theory. The main feature of this approach is that it takes advantage of the static nature of the nonlinearity, which allows to solve the control problem by focusing only in the linear dynamics. This formulation results in a simplified design procedure, because the original nonlinear model predictive control (MPC) problem turns into a linear one.

  10. Exercise therapy for osteoporosis: results of a randomised controlled trial.

    PubMed Central

    Preisinger, E; Alacamlioglu, Y; Pils, K; Bosina, E; Metka, M; Schneider, B; Ernst, E

    1996-01-01

    OBJECTIVE: To define the effects of therapeutic exercise on bone density and back complaints. METHODS: A randomised controlled trial with parallel groups was conducted in an outpatient clinic, Medical School, University of Vienna. Ninety two sedentary post-menopausal women with back problems were randomly allocated to either exercise (groups 1 and 2) or control (group 3, no exercise, n = 31); the exercise group was retrospectively subdivided into compliant (group 1, n = 27) and not fully compliant patients (group 2, n = 34). Regular, initially supervised therapeutic exercise aimed at restoring biomechanical function was performed for four years. Bone density in the forearm was measured by single photon absorptiometry at entry and after four years; subjective back complaints were documented. RESULTS: A significant decrease in bone density was observed in groups 2 and 3; no change was noted in group 1; back complaints decreased in group 1 only. CONCLUSIONS: Sedentary postmenopausal women may benefit from regular long term therapeutic exercise in terms of subjective back complaints and slowed loss of bone mass. PMID:8889112

  11. Robust Control Design via Linear Programming

    NASA Technical Reports Server (NTRS)

    Keel, L. H.; Bhattacharyya, S. P.

    1998-01-01

    This paper deals with the problem of synthesizing or designing a feedback controller of fixed dynamic order. The closed loop specifications considered here are given in terms of a target performance vector representing a desired set of closed loop transfer functions connecting various signals. In general these point targets are unattainable with a fixed order controller. By enlarging the target from a fixed point set to an interval set the solvability conditions with a fixed order controller are relaxed and a solution is more easily enabled. Results from the parametric robust control literature can be used to design the interval target family so that the performance deterioration is acceptable, even when plant uncertainty is present. It is shown that it is possible to devise a computationally simple linear programming approach that attempts to meet the desired closed loop specifications.

  12. Strategies for Increasing Recruitment to Randomised Controlled Trials: Systematic Review

    PubMed Central

    Caldwell, Patrina H. Y.; Hamilton, Sana; Tan, Alvin; Craig, Jonathan C.

    2010-01-01

    Background Recruitment of participants into randomised controlled trials (RCTs) is critical for successful trial conduct. Although there have been two previous systematic reviews on related topics, the results (which identified specific interventions) were inconclusive and not generalizable. The aim of our study was to evaluate the relative effectiveness of recruitment strategies for participation in RCTs. Methods and Findings A systematic review, using the PRISMA guideline for reporting of systematic reviews, that compared methods of recruiting individual study participants into an actual or mock RCT were included. We searched MEDLINE, Embase, The Cochrane Library, and reference lists of relevant studies. From over 16,000 titles or abstracts reviewed, 396 papers were retrieved and 37 studies were included, in which 18,812 of at least 59,354 people approached agreed to participate in a clinical RCT. Recruitment strategies were broadly divided into four groups: novel trial designs (eight studies), recruiter differences (eight studies), incentives (two studies), and provision of trial information (19 studies). Strategies that increased people's awareness of the health problem being studied (e.g., an interactive computer program [relative risk (RR) 1.48, 95% confidence interval (CI) 1.00–2.18], attendance at an education session [RR 1.14, 95% CI 1.01–1.28], addition of a health questionnaire [RR 1.37, 95% CI 1.14–1.66]), or a video about the health condition (RR 1.75, 95% CI 1.11–2.74), and also monetary incentives (RR1.39, 95% CI 1.13–1.64 to RR 1.53, 95% CI 1.28–1.84) improved recruitment. Increasing patients' understanding of the trial process, recruiter differences, and various methods of randomisation and consent design did not show a difference in recruitment. Consent rates were also higher for nonblinded trial design, but differential loss to follow up between groups may jeopardise the study findings. The study's main limitation was the necessity of

  13. Panax ginseng in randomised controlled trials: a systematic review.

    PubMed

    Shergis, Johannah L; Zhang, Anthony L; Zhou, Wenyu; Xue, Charlie C

    2013-07-01

    Panax ginseng C.A. Meyer is a common herb with many purported health benefits. However, there is no conclusive evidence supporting its use in the treatment of any particular disease. We conducted a systematic review to evaluate randomised controlled trials. Four English databases were searched with no publication date restriction. Included studies evaluated P. ginseng in patients with any type of disease or in healthy individuals. We assessed the quality of studies using the Cochrane risk of bias tool. Of the 475 potentially relevant studies, 65 met the inclusion criteria. These studies examined P. ginseng's effects on psychomotor performance (17 studies), physical performance (ten), circulatory system (eight), glucose metabolism (six), the respiratory system (five), erectile dysfunction (four), immunomodulation (four), quality of life/mood (four), antioxidant function (two), cancer (two), menopausal symptoms (two) and dry mouth (one). The risk of bias was unclear in most studies. Authors evaluated adverse events in 40 studies, with 135 minor events and no serious adverse events reported. P. ginseng shows promising results for improving glucose metabolism and moderating the immune response. This may have implications for several diseases including type 2 diabetes and chronic respiratory conditions. Further studies are needed to explore P. ginseng's potential as an effective treatment for these and other health conditions.

  14. Motivational interviewing for modifying diabetes risk: a randomised controlled trial

    PubMed Central

    Greaves, Colin J; Middlebrooke, Andrew; O'Loughlin, Lucy; Holland, Sandra; Piper, Jane; Steele, Anna; Gale, Tracy; Hammerton, Fenella; Daly, Mark

    2008-01-01

    Background Around 10–15% of adults aged over 40 years have pre-diabetes, which carries a high risk of progression to type 2 diabetes. Intensive lifestyle intervention reduces progression by as much as 58%. However, the cost and personnel requirements of these interventions are major obstacles to delivery in NHS primary care. Aim To assess the effectiveness of a low-cost intervention, delivered in primary care by non-NHS staff, to reduce the risk of diabetes through weight loss and physical activity. Design of study Pragmatic single-blind randomised controlled trial with researchers and statistician blinded to group allocation. Setting UK primary care. Method One-hundred and forty-one participants with a body mass index of 28 kg/m2 or more, but without diabetes or heart disease, received either information leaflets or individual behavioural counselling using motivational interviewing techniques. The intervention was delivered by five counsellors recruited from the local community. The primary outcomes were the proportions of participants meeting predefined targets for weight loss (5%) and moderate physical activity (150 minutes/week) after 6 months. Results Using intention-to-treat analysis, more people in the intervention group achieved the weight-loss target (24% versus 7% for controls; odds ratio [OR] = 3.96; 95% confidence interval [Cl] = 1.4 to 11.4; number needed to treat [NNT] = 6.1 (95% Cl = 4 to 21). The proportion achieving the physical activity target did not increase significantly (38% versus 28% for controls; OR = 1.6; 95% Cl = 0.7 to 3.8). Conclusion Short-term weight loss, at a level which, if sustained, is clinically meaningful for reducing diabetes risk, is achievable in primary care, without excessive use of NHS monetary or personnel resources. PMID:18682011

  15. Application of stochastic robustness to aircraft control systems

    NASA Technical Reports Server (NTRS)

    Ryan, Laura E.

    1990-01-01

    Guaranteeing robustness has long been an important design objective of control system analysis. Stochastic robustness is a simple numerical procedure that can be used to measure and gain insight into robustness properties associated with linear control systems. In the realm of aircraft control systems, problems such as the effects of flight condition perturbations and model-order uncertainties on robustness are easily and effectively analyzed using stochastic robustness. The concept of stochastic robustness is reviewed and examples are presented demonstrating its use in flight control system analysis.

  16. Robust, Practical Adaptive Control for Launch Vehicles

    NASA Technical Reports Server (NTRS)

    Orr, Jeb. S.; VanZwieten, Tannen S.

    2012-01-01

    A modern mechanization of a classical adaptive control concept is presented with an application to launch vehicle attitude control systems. Due to a rigorous flight certification environment, many adaptive control concepts are infeasible when applied to high-risk aerospace systems; methods of stability analysis are either intractable for high complexity models or cannot be reconciled in light of classical requirements. Furthermore, many adaptive techniques appearing in the literature are not suitable for application to conditionally stable systems with complex flexible-body dynamics, as is often the case with launch vehicles. The present technique is a multiplicative forward loop gain adaptive law similar to that used for the NASA X-15 flight research vehicle. In digital implementation with several novel features, it is well-suited to application on aerodynamically unstable launch vehicles with thrust vector control via augmentation of the baseline attitude/attitude-rate feedback control scheme. The approach is compatible with standard design features of autopilots for launch vehicles, including phase stabilization of lateral bending and slosh via linear filters. In addition, the method of assessing flight control stability via classical gain and phase margins is not affected under reasonable assumptions. The algorithm s ability to recover from certain unstable operating regimes can in fact be understood in terms of frequency-domain criteria. Finally, simulation results are presented that confirm the ability of the algorithm to improve performance and robustness in realistic failure scenarios.

  17. Multi-application controls: Robust nonlinear multivariable aerospace controls applications

    NASA Technical Reports Server (NTRS)

    Enns, Dale F.; Bugajski, Daniel J.; Carter, John; Antoniewicz, Bob

    1994-01-01

    This viewgraph presentation describes the general methodology used to apply Honywell's Multi-Application Control (MACH) and the specific application to the F-18 High Angle-of-Attack Research Vehicle (HARV) including piloted simulation handling qualities evaluation. The general steps include insertion of modeling data for geometry and mass properties, aerodynamics, propulsion data and assumptions, requirements and specifications, e.g. definition of control variables, handling qualities, stability margins and statements for bandwidth, control power, priorities, position and rate limits. The specific steps include choice of independent variables for least squares fits to aerodynamic and propulsion data, modifications to the management of the controls with regard to integrator windup and actuation limiting and priorities, e.g. pitch priority over roll, and command limiting to prevent departures and/or undesirable inertial coupling or inability to recover to a stable trim condition. The HARV control problem is characterized by significant nonlinearities and multivariable interactions in the low speed, high angle-of-attack, high angular rate flight regime. Systematic approaches to the control of vehicle motions modeled with coupled nonlinear equations of motion have been developed. This paper will discuss the dynamic inversion approach which explicity accounts for nonlinearities in the control design. Multiple control effectors (including aerodynamic control surfaces and thrust vectoring control) and sensors are used to control the motions of the vehicles in several degrees-of-freedom. Several maneuvers will be used to illustrate performance of MACH in the high angle-of-attack flight regime. Analytical methods for assessing the robust performance of the multivariable control system in the presence of math modeling uncertainty, disturbances, and commands have reached a high level of maturity. The structured singular value (mu) frequency response methodology is presented

  18. Immunosuppression for progressive membranous nephropathy: a UK randomised controlled trial

    PubMed Central

    Howman, Andrew; Chapman, Tracey L; Langdon, Maria M; Ferguson, Caroline; Adu, Dwomoa; Feehally, John; Gaskin, Gillian J; Jayne, David RW; O'Donoghue, Donal; Boulton-Jones, Michael; Mathieson, Peter W

    2013-01-01

    Summary Background Membranous nephropathy leads to end-stage renal disease in more than 20% of patients. Although immunosuppressive therapy benefits some patients, trial evidence for the subset of patients with declining renal function is not available. We aimed to assess whether immunosuppression preserves renal function in patients with idiopathic membranous nephropathy with declining renal function. Methods This randomised controlled trial was undertaken in 37 renal units across the UK. We recruited patients (18–75 years) with biopsy-proven idiopathic membranous nephropathy, a plasma creatinine concentration of less than 300 μmol/L, and at least a 20% decline in excretory renal function measured in the 2 years before study entry, based on at least three measurements over a period of 3 months or longer. Patients were randomly assigned (1:1:1) by a random number table to receive supportive treatment only, supportive treatment plus 6 months of alternating cycles of prednisolone and chlorambucil, or supportive treatment plus 12 months of ciclosporin. The primary outcome was a further 20% decline in renal function from baseline, analysed by intention to treat. The trial is registered as an International Standard Randomised Controlled Trial, number 99959692. Findings We randomly assigned 108 patients, 33 of whom received prednisolone and chlorambucil, 37 ciclosporin, and 38 supportive therapy alone. Two patients (one who received ciclosporin and one who received supportive therapy) were ineligible, so were not included in the intention-to-treat analysis, and 45 patients deviated from protocol before study end, mostly as a result of minor dose adjustments. Follow up was until primary endpoint or for minimum of 3 years if primary endpoint was not reached. Risk of further 20% decline in renal function was significantly lower in the prednisolone and chlorambucil group than in the supportive care group (19 [58%] of 33 patients reached endpoint vs 31 [84%] of 37, hazard

  19. Famciclovir for ophthalmic zoster: a randomised aciclovir controlled study

    PubMed Central

    Tyring, S.; Engst, R.; Corriveau, C.; Robillard, N.; Trottier, S.; Van Slycken, S.; Crann, R.; Locke, L.; Saltzman, R.; Palestine, A.

    2001-01-01

    AIMS—To compare the efficacy and safety of famciclovir with aciclovir for the treatment of ophthalmic zoster.
METHODS—Randomised, double masked, aciclovir controlled, parallel group in 87 centres worldwide including 454 patients with ophthalmic zoster of trigeminal nerve (V1) comprised the intent to treat population. Oral famciclovir 500 mg three times daily or oral aciclovir 800 mg five times daily for 7 days. Assessments included day 0 (screening), days 3 and 7 (during treatment), days 10, 14, 21, 28 and monthly thereafter, up to 6 months (follow up). Proportion of patients who experienced ocular manifestations, severe manifestations and non-severe manifestations; loss of visual acuity was the main outcome measure.
RESULTS—The percentage of patients who experienced one or more ocular manifestations was similar for famciclovir (142/245, 58.0%) and aciclovir (114/196, 58.2%) recipients, with no significant difference between groups (OR 0.99; 95% CI 0.68, 1.45). The percentage of patients who experienced severe and non-severe manifestations was similar between groups, with no significant difference. The prevalence of individual ocular manifestations was comparable between groups. There was no significant difference between groups for visual acuity loss.
CONCLUSION—Famciclovir 500 mg three times daily was well tolerated and demonstrated efficacy similar to aciclovir 800 mg five times daily.

 PMID:11316720

  20. Thermoregulatory effects of swaddling in Mongolia: a randomised controlled study

    PubMed Central

    Tsogt, Bazarragchaa; Manaseki-Holland, Semira; Pollock, Jon; Blair, Peter S; Fleming, Peter

    2016-01-01

    Objective To investigate thermal balance of infants in a Mongolian winter, and compare the effects of traditional swaddling with an infant sleeping-bag in apartments or traditional tents (Gers). Design A substudy within a randomised controlled trial. Setting Community in Ulaanbaatar, Mongolia. Subjects A stratified randomly selected sample of 40 swaddled and 40 non-swaddled infants recruited within 48 h of birth. Intervention Sleeping-bags and baby outfits of total thermal resistance equivalent to that of swaddled babies. Outcome measure Digital recordings of infants’ core, peripheral, environmental and microenvironmental temperatures at 30-s intervals over 24 h at ages 1 month and 3 months. Results In Gers, indoor temperatures varied greatly (<0–>25°C), but remained between 20°C and 22°C, in apartments. Despite this, heavy wrapping, bed sharing and partial head covering, infant core and peripheral temperatures were similar and no infants showed evidence of significant heat or cold stress whether they were swaddled or in sleeping-bags. At 3 months, infants in sleeping-bags showed the ‘mature’ diurnal pattern of a fall in core temperature after sleep onset, accompanied by a rise in peripheral temperature, with a reverse pattern later in the night, just before awakening. This pattern was not related to room temperature, and was absent in the swaddled infants, suggesting that the mature diurnal pattern may develop later in them. Conclusions No evidence of cold stress was found. Swaddling had no identifiable thermal advantages over sleeping-bags during the coldest times, and in centrally heated apartments could contribute to the risk of overheating during the daytime. Trial registration number ISRTN01992617. PMID:26515228

  1. Vitamin E supplementation and macular degeneration: randomised controlled trial

    PubMed Central

    Taylor, Hugh R; Tikellis, Gabriella; Robman, Luba D; McCarty, Catherine A; McNeil, John J

    2002-01-01

    Objective To determine whether vitamin E supplementation influences the incidence or rate of progression of age related maculopathy (AMD). Design Prospective randomised placebo controlled clinical trial. Setting An urban study centre in a residential area supervised by university research staff. Participants 1193 healthy volunteers aged between 55 and 80 years; 73% completed the trial on full protocol. Interventions Vitamin E 500 IU or placebo daily for four years. Main outcome measures Primary outcome: development of early age related macular degeneration in retinal photographs. Other measures included alternative definitions of age related macular degeneration, progression, changes in component features, visual acuity, and visual function Results The incidence of early age related macular degeneration (early AMD 3) was 8.6% in those receiving vitamin E versus 8.1% in those on placebo (relative risk 1.05, 95% confidence interval 0.69 to 1.61). For late disease the incidence was 0.8% versus 0.6% (1.36, 0.67 to 2.77). Further analysis showed no consistent differences in secondary outcomes. Conclusion Daily supplement with vitamin E supplement does not prevent the development or progression of early or later stages of age related macular degeneration. What is already known on this topicAge related macular degeneration is the leading cause of loss of vision and blindness in elderly people; for people aged ⩾90 years, two out of every three will be affected and one in four will become blindCurrently, there are no methods of prevention or treatment in most cases, though a third of cases are due to cigarette smokingAntioxidant vitamins have been suggested as a possible preventionWhat this study addsDaily supplementation with 500 mg vitamin E for four years did not alter the incidence or progression of AMD PMID:12098721

  2. Does telecare prolong community living in dementia? A study protocol for a pragmatic, randomised controlled trial

    PubMed Central

    2013-01-01

    Background Assistive technology and telecare (ATT) are relatively new ways of delivering care and support to people with social care needs. It is claimed that ATT reduces the need for community care, prevents unnecessary hospital admission, and delays or prevents admission into residential or nursing care. The current economic situation in England has renewed interest in ATT instead of community care packages. However, at present, the evidence base to support claims about the impact and effectiveness of ATT is limited, despite its potential to mitigate the high financial cost of caring for people with dementia and the social and psychological cost to unpaid carers. Method/design ATTILA (Assistive Technology and Telecare to maintain Independent Living At Home for People with Dementia) is a pragmatic, multi-centre, randomised controlled trial over 104 weeks that compares outcomes for people with dementia who receive ATT and those who receive equivalent community services but not ATT. The study hypothesis is that fewer people in the ATT group will go into institutional care over the 4-year period for which the study is funded. The study aims to recruit 500 participants, living in community settings, with dementia or significant cognitive impairment, who have recently been referred to social services. Primary outcome measures are time in days from randomisation to institutionalisation and cost effectiveness. Secondary outcomes are caregiver burden, health-related quality of life in carers, number and severity of serious adverse events, and data on acceptability, applicability and reliability of ATT intervention packages. Assessments will be undertaken in weeks 0 (baseline), 12, 24, 52 and 104 or until institutionalisation or withdrawal of the participant from the trial. Discussion In a time of financial austerity, CASSRs in England are increasingly turning to ATT in the belief that it will deliver good outcomes for less money. There is an absence of robust evidence for

  3. Robust control for snake maneuver design of missile

    NASA Astrophysics Data System (ADS)

    Kun, Ya; Chen, Xin; Li, Chuntao

    2017-01-01

    For the performance of missile with high Mach number and strongly nonlinear dynamics, this paper uses robust control to design maneuver controller. Robust servomechanism linear quadratic regulator (RSLQR) control is used to form the inner loop and proportional-plus-integral (PI) control is used to provide yawing tracking with no error. Contrast simulations under three types of deviation have been done to confirm robustness of the RSLQR-plus-PI control. Simulation results shows that RSLQR-plus-PI control would resist the disturbance and maintain the properties of the controller, guarantee the robustness and stability of missile more effectively than pure PI control.

  4. Robust steering control of spacecraft carrier rockets

    NASA Astrophysics Data System (ADS)

    Correa, Adriana Elysa Alimandro; da Rosa, Alex; Ferreira, Henrique Cezar; Ishihara, Joao Yoshiyuki; Borges, Renato Alves; Sheptun, Yuri Dmitrievich

    In the year of 2003 it was established a cooperation agreement between Ukraine and Brazil for utilization of Cyclone-4 launch vehicle at Alcantara Launch Center. The company responsible for the marketing and operation of launch services is the company bi-national Alcantara Cyclone Space (ACS). The Cyclone-4 launch vehicle is the newest version of the Ukrainian Cyclone family launchers developed by Yuzhnoye State Design Office. This family has been used for many successful spacecrafts launches since 1969. This paper is concerned with the yaw stabilization problem around a nominal trajectory for the third stage of a satellite carrier rocket similar to the Cyclone-4. Only the steering machine of the main engine is considered as actuator. The dynamic behavior of the third stage around the nominal trajectory is modeled as a fourthorder time-varying linear system whereas the steering machine is modeled as a linear dynamical system up to third order. The values of the parameters of the steering machine model are unknown, however belonging to known intervals. As the main result, the stabilization problem is solved with a proportional derivative (PD) controller. The proposed tuning approach takes into account the robustness of the controller with respect to the steering machine model uncertainties. The performance of the PD controller is demonstrated by simulation results.

  5. Combined Integral and Robust Control of the Segmented Mirror Telescope

    DTIC Science & Technology

    2009-12-01

    60 Hz, Best Perf ............ 41 Figure 29. Zernike Control Model ........................................................................ 42 Figure...builds on previous robust control design by combining classical control with an H robust controller on a Singular Value Decomposition reduced model ...It also presents reduction using Zernike polynomials and applies it to the integral control model as an alternate to Singular Value Decomposition

  6. Computer-aided-analysis of linear control system robustness

    NASA Technical Reports Server (NTRS)

    Stengel, Robert F.; Ray, Laura R.

    1990-01-01

    Stochastic robustness is a simple technique used to estimate the stability and performance robustness of linear, time-invariant systems. The use of high-speed graphics workstations and control system design software in stochastic robustness analysis is discussed and demonstrated. It is shown that stochastic robustness makes good use of modern computational and graphic tools, and it is easily implemented using commercial control system design and analysis software.

  7. Testing the activitystat hypothesis: a randomised controlled trial protocol

    PubMed Central

    2012-01-01

    Background The activitystat hypothesis proposes that when physical activity or energy expenditure is increased or decreased in one domain, there will be a compensatory change in another domain to maintain an overall, stable level of physical activity or energy expenditure. To date, there has been no experimental study primarily designed to test the activitystat hypothesis in adults. The aim of this trial is to determine the effect of two different imposed exercise loads on total daily energy expenditure and physical activity levels. Methods This study will be a randomised, multi-arm, parallel controlled trial. Insufficiently active adults (as determined by the Active Australia survey) aged 18–60 years old will be recruited for this study (n=146). Participants must also satisfy the Sports Medicine Australia Pre-Exercise Screening System and must weigh less than 150 kg. Participants will be randomly assigned to one of three groups using a computer-generated allocation sequence. Participants in the Moderate exercise group will receive an additional 150 minutes of moderate to vigorous physical activity per week for six weeks, and those in the Extensive exercise group will receive an additional 300 minutes of moderate to vigorous physical activity per week for six weeks. Exercise targets will be accumulated through both group and individual exercise sessions monitored by heart rate telemetry. Control participants will not be given any instructions regarding lifestyle. The primary outcome measures are activity energy expenditure (doubly labeled water) and physical activity (accelerometry). Secondary measures will include resting metabolic rate via indirect calorimetry, use of time, maximal oxygen consumption and several anthropometric and physiological measures. Outcome measures will be conducted at baseline (zero weeks), mid- and end-intervention (three and six weeks) with three (12 weeks) and six month (24 week) follow-up. All assessors will be blinded to group

  8. Mobile phone SMS messages can enhance healthy behaviour: a meta-analysis of randomised controlled trials.

    PubMed

    Orr, Jayne A; King, Robert J

    2015-01-01

    Healthy behaviour, such as smoking cessation and adherence to prescribed medications, mitigates illness risk factors but health behaviour change can be challenging. Mobile phone short-message service (SMS) messages are increasingly used to deliver interventions designed to enhance healthy behaviour. This meta-analysis used a random-effects model to synthesise 38 randomised controlled trials that investigated the efficacy of SMS messages to enhance healthy behaviour. Participants (N = 19,641) lived in developed and developing countries and were diverse with respect to age, ethnicity, socioeconomic background and health behaviours targeted for change. SMS messages had a small, positive, significant effect (g = 0.291) on a broad range of healthy behaviour. This effect was maximised when multiple SMS messages per day were used (g = 0.395) compared to using lower frequencies (daily, multiple per week and once-off) (g = 0.244). The low heterogeneity in this meta-analysis (I (2) = 38.619) supports reporting a summary effect size and implies that the effect of SMS messaging is robust, regardless of population characteristics or healthy behaviour targeted. SMS messaging is a simple, cost-effective intervention that can be automated and can reach any mobile phone owner. While the effect size is small, potential health benefits are well worth achieving.

  9. Robust association of the LPA locus with LDLc lowering response to statin treatment in a meta-analysis of 30,467 individuals from both randomised control trials and observational studies and association with coronary artery disease outcome during statin treatment

    PubMed Central

    Donnelly, Louise A; van Zuydam, Natalie R; Zhou, Kaixin; Tavendale, Roger; Carr, Fiona; Maitland-van der Zee, Anke H; Leusink, Maarten; de Boer, Anthonius; Doevendans, Pieter A; WAsselbergs, Folkert; Morris, Andrew D; Pearson, Ewan R; Klungel, Olaf H; Doney, Alex SF; Palmer, Colin NA

    2014-01-01

    Objectives The LPA SNP rs10455872 has been associated with low density lipoprotein cholesterol (LDLc) lowering response to statins in several randomised control trials (RCTs) and is a known coronary artery disease (CAD) marker. However it is unclear what residual risk of CAD this marker may have during statin treatment. Methods Using electronic medical records linked to the GoDARTS genotyped population we identified over 8000 patients on statins in Tayside, Scotland. Results We replicated the findings of the RCTs, with the G allele of rs10455872 being associated with a 0.10mmol/l per allele poorer reduction in LDLc in response to statin treatment, and conducted a meta-analysis with previously published RCTs (P=1.46×10−29, n=30,467). We demonstrate an association between rs10455872 and CAD in statin treated individuals and have replicated this finding in the Utrecht Cardiovascular Pharmacogenetics Study (combined odds ratio 1·41, 95% CI 1.17-1.68, P=4.5×10−5, n=8822) suggesting that statin treatment does not abrogate this well-established genetic risk for CAD. Furthermore in a Cox proportional hazards model with LDLc measured time dependently we demonstrated the relationship between CAD and rs10455872 was independent of LDLc during statin treatment. Conclusion Individuals with the G allele of rs10455872, which represents approximately 1 in 7 patients, have a higher risk of CAD than the majority of the population even after treatment with statins, and therefore represent a vulnerable group requiring an alternative medication in addition to statin treatment. PMID:23903772

  10. Robust tracking control of a magnetically suspended rigid body

    NASA Technical Reports Server (NTRS)

    Lim, Kyong B.; Cox, David E.

    1994-01-01

    This study is an application of H-infinity and micro-synthesis for designing robust tracking controllers for the Large Angle Magnetic Suspension Test Facility. The modeling, design, analysis, simulation, and testing of a control law that guarantees tracking performance under external disturbances and model uncertainties is investigated. The type of uncertainties considered and the tracking performance metric used is discussed. This study demonstrates the tradeoff between tracking performance at low frequencies and robustness at high frequencies. Two sets of controllers were designed and tested. The first set emphasized performance over robustness, while the second set traded off performance for robustness. Comparisons of simulation and test results are also included. Current simulation and experimental results indicate that reasonably good robust tracking performance can be attained for this system using multivariable robust control approach.

  11. Intelligence and Persisting with Medication for Two Years: Analysis in a Randomised Controlled Trial

    ERIC Educational Resources Information Center

    Deary, Ian J.; Gale, Catharine R.; Stewart, Marlene C. W.; Fowkes, F. Gerald R.; Murray, Gordon D.; Batty, G. David; Price, Jacqueline F.

    2009-01-01

    The study examined whether verbal intelligence is associated with persisting to take medication for up to two years. The design is a prospective follow-up of compliance with taking medication in high-risk individuals participating in a randomised, placebo-controlled trial set in Central Scotland. Participants were 1993 people aged between 50 and…

  12. A New Social Communication Intervention for Children with Autism: Pilot Randomised Controlled Treatment Study Suggesting Effectiveness

    ERIC Educational Resources Information Center

    Aldred, Catherine; Green, Jonathan; Adams, Catherine

    2004-01-01

    Background: Psychosocial treatments are the mainstay of management of autism in the UK but there is a notable lack of a systematic evidence base for their effectiveness. Randomised controlled trial (RCT) studies in this area have been rare but are essential because of the developmental heterogeneity of the disorder. We aimed to test a new…

  13. Reading and Language Intervention for Children at Risk of Dyslexia: A Randomised Controlled Trial

    ERIC Educational Resources Information Center

    Duff, Fiona J.; Hulme, Charles; Grainger, Katy; Hardwick, Samantha J.; Miles, Jeremy N. V.; Snowling, Margaret J.

    2014-01-01

    Background: Intervention studies for children at risk of dyslexia have typically been delivered preschool, and show short-term effects on letter knowledge and phoneme awareness, with little transfer to literacy. Methods: This randomised controlled trial evaluated the effectiveness of a reading and language intervention for 6-year-old children…

  14. Representation of People with Intellectual Disabilities in Randomised Controlled Trials on Antipsychotic Treatment for Behavioural Problems

    ERIC Educational Resources Information Center

    Scheifes, A.; Stolker, J. J.; Egberts, A. C. G.; Nijman, H. L. I.; Heerdink, E. R.

    2011-01-01

    Background: Behavioural problems are common in people with intellectual disability (ID) and are often treated with antipsychotics. Aim: To establish the frequency and characteristics of people with ID included in randomised controlled trials (RCTs) on antipsychotic treatment for behavioural problems, and to investigate the quality of these RCTs.…

  15. Review of Randomised Controlled Trials of Internet Interventions for Mental Disorders and Related Conditions

    ERIC Educational Resources Information Center

    Griffiths, Kathleen M.; Christensen, Helen

    2006-01-01

    Self-help Internet interventions have the potential to enable consumers to play a central role in managing their own health. This paper contains a systematic review of 15 randomised controlled trials of the effectiveness of self-help Internet interventions for mental disorders and related conditions. Conditions addressed by the interventions…

  16. Educational Benefits of Using Game Consoles in a Primary Classroom: A Randomised Controlled Trial

    ERIC Educational Resources Information Center

    Miller, David J.; Robertson, Derek P.

    2011-01-01

    It is known that computer games are motivating for children, but there is limited direct evidence of their effects on classroom learning. The studies that are available tend to be limited in terms of output data reported, or small in scale, or both. The aim of this randomised controlled trial was to upscale a recent study by Miller and Robertson…

  17. Skills Training to Avoid Inadvertent Plagiarism: Results from a Randomised Control Study

    ERIC Educational Resources Information Center

    Newton, Fiona J.; Wright, Jill D.; Newton, Joshua D.

    2014-01-01

    Plagiarism continues to be a concern within academic institutions. The current study utilised a randomised control trial of 137 new entry tertiary students to assess the efficacy of a scalable short training session on paraphrasing, patch writing and plagiarism. The results indicate that the training significantly enhanced students' overall…

  18. Integrated identification and robust control tuning for large space structures

    NASA Technical Reports Server (NTRS)

    Yam, Y.; Bayard, D. S.; Scheid, R. E.

    1990-01-01

    System identification is studied for the explicit purpose of supporting modern H-infinity robust control design objectives. In the analysis, the true plant is not assumed to be in the identification model set. An integrated identification/robust control problem is posed in which the optimal solution guarantees the best robust performance relative to the system information contained in a given experimental data set. A numerical example demonstrating an approximate solution to the problem indicates the usefulness of the approach.

  19. Gabapentin for the Management of Chronic Pelvic Pain in Women (GaPP1): A Pilot Randomised Controlled Trial

    PubMed Central

    Lewis, Steff C.; Bhattacharya, Siladitya; Wu, Olivia; Vincent, Katy; Jack, Stuart A.; Critchley, Hilary O. D.; Porter, Maureen A.; Cranley, Denise; Wilson, John A.; Horne, Andrew W.

    2016-01-01

    Chronic pelvic pain (CPP) affects 2.1–24% of women. Frequently, no underlying pathology is identified, and the pain is difficult to manage. Gabapentin is prescribed for CPP despite no robust evidence of efficacy. We performed a pilot trial in two UK centres to inform the planning of a future multicentre RCT to evaluate gabapentin in CPP management. Our primary objective was to determine levels of participant recruitment and retention. Secondary objectives included estimating potential effectiveness, acceptability to participants of trial methodology, and cost-effectiveness of gabapentin. Women with CPP and no obvious pelvic pathology were assigned to an increasing regimen of gabapentin (300-2700mg daily) or placebo. We calculated the proportion of eligible women randomised, and of randomised participants who were followed up to six months. The analyses by treatment group were by intention-to-treat. Interviews were conducted to evaluate women’s experiences of the trial. A probabilistic decision analytical model was used to estimate cost-effectiveness. Between September 2012–2013, 47 women (34% of those eligible) were randomised (22 to gabapentin, 25 to placebo), and 25 (53%) completed six-month follow-up. Participants on gabapentin had less pain (BPI difference 1.72 points, 95% CI:0.07–3.36), and an improvement in mood (HADS difference 4.35 points, 95% CI:1.97–6.73) at six months than those allocated placebo. The majority of participants described their trial experience favorably. At the UK threshold for willingness-to-pay, the probabilities of gabapentin or no treatment being cost-effective are similar. A pilot trial assessing gabapentin for CPP was feasible, but uncertainty remains, highlighting the need for a large definitive trial. Trial registration Controlled-Trials.com ISRCTN45178534 PMID:27070434

  20. A criterion for joint optimization of identification and robust control

    NASA Technical Reports Server (NTRS)

    Bayard, D. S.; Yam, Y.; Mettler, E.

    1992-01-01

    A criterion for system identification is developed that is consistent with the intended used of the fitted model for modern robust control synthesis. Specifically, a joint optimization problem is posed which simultaneously solves the plant model estimate and control design, so as to optimize robust performance over the set of plants consistent with a specified experimental data set.

  1. Identification and robust control of an experimental servo motor.

    PubMed

    Adam, E J; Guestrin, E D

    2002-04-01

    In this work, the design of a robust controller for an experimental laboratory-scale position control system based on a dc motor drive as well as the corresponding identification and robust stability analysis are presented. In order to carry out the robust design procedure, first, a classic closed-loop identification technique is applied and then, the parametrization by internal model control is used. The model uncertainty is evaluated under both parametric and global representation. For the latter case, an interesting discussion about the conservativeness of this description is presented by means of a comparison between the uncertainty disk and the critical perturbation radius approaches. Finally, conclusions about the performance of the experimental system with the robust controller are discussed using comparative graphics of the controlled variable and the Nyquist stability margin as a robustness measurement.

  2. Stochastic robustness of linear control systems

    NASA Technical Reports Server (NTRS)

    Stengel, Robert F.; Ryan, Laura E.

    1990-01-01

    A simple numerical procedure for estimating the stochastic robustness of a linear, time-invariant system is described. Monte Carlo evaluation of the system's eigenvalues allows the probability of instability and the related stochastic root locus to be estimated. This definition of robustness is an alternative to existing deterministic definitions that address both structured and unstructured parameter variations directly. This analysis approach treats not only Gaussian parameter uncertainties but non-Gaussian cases, including uncertain-but-bounded variations. Trivial extensions of the procedure admit alternate discriminants to be considered. Thus, the probabilities that stipulated degrees of instability will be exceeded or that closed-loop roots will leave desirable regions also can be estimated. Results are particularly amenable to graphical presentation.

  3. Robustness Analysis and Optimally Robust Control Design via Sum-of-Squares

    NASA Technical Reports Server (NTRS)

    Dorobantu, Andrei; Crespo, Luis G.; Seiler, Peter J.

    2012-01-01

    A control analysis and design framework is proposed for systems subject to parametric uncertainty. The underlying strategies are based on sum-of-squares (SOS) polynomial analysis and nonlinear optimization to design an optimally robust controller. The approach determines a maximum uncertainty range for which the closed-loop system satisfies a set of stability and performance requirements. These requirements, de ned as inequality constraints on several metrics, are restricted to polynomial functions of the uncertainty. To quantify robustness, SOS analysis is used to prove that the closed-loop system complies with the requirements for a given uncertainty range. The maximum uncertainty range, calculated by assessing a sequence of increasingly larger ranges, serves as a robustness metric for the closed-loop system. To optimize the control design, nonlinear optimization is used to enlarge the maximum uncertainty range by tuning the controller gains. Hence, the resulting controller is optimally robust to parametric uncertainty. This approach balances the robustness margins corresponding to each requirement in order to maximize the aggregate system robustness. The proposed framework is applied to a simple linear short-period aircraft model with uncertain aerodynamic coefficients.

  4. Cost averaging techniques for robust control of flexible structural systems

    NASA Technical Reports Server (NTRS)

    Hagood, Nesbitt W.; Crawley, Edward F.

    1991-01-01

    Viewgraphs on cost averaging techniques for robust control of flexible structural systems are presented. Topics covered include: modeling of parameterized systems; average cost analysis; reduction of parameterized systems; and static and dynamic controller synthesis.

  5. Robust attitude tracking control of small-scale unmanned helicopter

    NASA Astrophysics Data System (ADS)

    Wang, Xiafu; Chen, You; Lu, Geng; Zhong, Yisheng

    2015-06-01

    Robust attitude control problem for small-scale unmanned helicopters is investigated to improve attitude control performances of roll and pitch channels under both small and large amplitude manoeuvre flight conditions. The model of the roll or pitch angular dynamics is regarded as a nominal single-input single-output linear system with equivalent disturbances which contain nonlinear uncertainties, coupling-effects, parameter perturbations, and external disturbances. Based on the signal compensation method, a robust controller is designed with two parts: a proportional-derivative controller and a robust compensator. The designed controller is linear and time-invariant, so it can be easily realised. The robust properties of the closed-loop system are proven. According to the ADS-33E-PRF military rotorcraft standard, the controller can achieve top control performances. Experimental results demonstrate the effectiveness of the proposed control strategy.

  6. Conductive Education as a Method of Stroke Rehabilitation: A Single Blinded Randomised Controlled Feasibility Study

    PubMed Central

    Jutley-Neilson, Jagjeet; Russell, Nicholas C. C.; Sackley, Catherine M.

    2016-01-01

    Background. Conductive Education for stroke survivors has shown promise but randomised evidence is unavailable. This study assessed the feasibility of a definitive randomised controlled trial to evaluate efficacy. Methods. Adult stroke survivors were recruited through local community notices. Those completing the baseline assessment were randomised using an online program and group allocation was independent. Intervention group participants received 10 weekly 1.5-hour sessions of Conductive Education at the National Institute of Conductive Education in Birmingham, UK. The control group participants attended two group meetings. The study evaluated the feasibility of recruitment procedures, delivery of the intervention, retention of participants, and appropriateness of outcome measures and data collection methods. Independent assessments included the Barthel Index, the Stroke Impact Scale, the Timed Up and Go test, and the Hospital Anxiety and Depression Scale. Results. Eighty-two patients were enrolled; 77 completed the baseline assessment (46 men, mean age 62.1 yrs.) and were randomised. 70 commenced the intervention (n = 37) or an equivalent waiting period (n = 33). 32/37 completed the 10-week training and 32/33 the waiting period. There were no missing items from completed questionnaires and no adverse events. Discussion. Recruitment, intervention, and assessment methods worked well. Transport issues for intervention and assessment appointments require review. Conclusion. A definitive trial is feasible. This trial is registered with ISRCTN84064492. PMID:27418997

  7. Robust transition control of a Martian coaxial tiltrotor aerobot

    NASA Astrophysics Data System (ADS)

    Zhao, Wei; Underwood, Craig

    2014-06-01

    Hyperion is an autonomous solar-electric powered coaxial tiltrotor aerobot proposed to investigate the Isidis Planitia region on Mars. The objective of this paper is to propose a robust control strategy for transition flight between hover and cruise based on the supervisory control method and the linear robust control method. The proposed transition controller has two levels. The lower level is a series of candidate controllers for the subproblems, which are obtained by the operation of divide and conquer. The higher level uses the state variables to determine which lower level candidate controller should be used. The candidate controllers are solved using the μ synthesis and the conventional longitudinal and lateral control loops. The robustness of the candidate controllers is guaranteed by the robust control theory. The stability and robustness of the transition controller is determined by the switch logic in the higher level. The stability of the proposed control strategy is analyzed. A 6 Degree of Freedom simulation with uncertain aerodynamic model is used to show the robustness and the performance of the proposed controller.

  8. Structured Robust Loop shaping control for HIMAT System Using PSO

    NASA Astrophysics Data System (ADS)

    Kaitwanidvilai, Somyot; Jangwanitlert, Anuwat; Parnichkun, Manukid

    2009-01-01

    Robust loop shaping control is a feasible method for designing a robust controller; however, the controller designed by this method is complicated and difficult to implement practically. To overcome this problem, in this paper, a new design technique of a fixed-structure robust loop shaping controller for a highly maneuverable airplane, HIMAT, is proposed. The performance and robust stability conditions of the designed system satisfying H∞ loop shaping control are formulated as the objective function in the optimization problem. Particle Swarm Optimization (PSO) technique is adopted to solve this problem and to achieve the control parameters of the proposed controller. Simulation results demonstrate that the proposed approach is numerically efficient and leads to performance comparable to that of the other method.

  9. Robust Control Design for Systems With Probabilistic Uncertainty

    NASA Technical Reports Server (NTRS)

    Crespo, Luis G.; Kenny, Sean P.

    2005-01-01

    This paper presents a reliability- and robustness-based formulation for robust control synthesis for systems with probabilistic uncertainty. In a reliability-based formulation, the probability of violating design requirements prescribed by inequality constraints is minimized. In a robustness-based formulation, a metric which measures the tendency of a random variable/process to cluster close to a target scalar/function is minimized. A multi-objective optimization procedure, which combines stability and performance requirements in time and frequency domains, is used to search for robustly optimal compensators. Some of the fundamental differences between the proposed strategy and conventional robust control methods are: (i) unnecessary conservatism is eliminated since there is not need for convex supports, (ii) the most likely plants are favored during synthesis allowing for probabilistic robust optimality, (iii) the tradeoff between robust stability and robust performance can be explored numerically, (iv) the uncertainty set is closely related to parameters with clear physical meaning, and (v) compensators with improved robust characteristics for a given control structure can be synthesized.

  10. Psychosocial consequences of allocation to lung cancer screening: a randomised controlled trial

    PubMed Central

    Aggestrup, Louise Mosborg; Hestbech, Mie Sara; Siersma, Volkert; Pedersen, Jesper Holst

    2012-01-01

    Objective To examine the psychosocial consequences of being allocated to the control group as compared with the screen group in a randomised lung cancer screening trial. Method The Danish Lung Cancer Screening Trial, a randomised controlled trial, ran from 2004 to 2010 with the purpose of investigating the benefits and harms of lung cancer screening. The participants in Danish Lung Cancer Screening Trial were randomised to either the control group or the screen group and were asked to complete the questionnaires Consequences Of Screening and Consequences Of Screening in Lung Cancer (COS-LC). The Consequences Of Screening and the COS-LC were used to examine the psychosocial consequences of participating in the study, by comparing the control and the screen groups' responses at the prevalence and at the incidence round. Results There was no statistically significant difference in socio-demographic characteristics or smoking habits between the two groups. Responses to the COS-LC collected before the incidence round were statistically significantly different on the scales ‘anxiety’, ‘behaviour’, ‘dejection’, ‘self-blame’, ‘focus on airway symptoms’ and ‘introvert’, with the control group reporting higher negative psychosocial consequences. Furthermore, the participants in both the control and the screen groups exhibited a mean increase in negative psychosocial consequences when their responses from the prevalence round were compared with their responses from the first incidence round. Conclusions Participation in a randomised controlled trial on lung cancer screening has negative psychosocial consequences for the apparently healthy participants—both the participants in the screen group and the control group. This negative impact was greatest for the control group. PMID:22382119

  11. Results of a feasibility randomised controlled trial (RCT) for WATCH IT: a programme for obese children and adolescents

    PubMed Central

    Farrin, Amanda; Christie, Deborah; Jebb, Susan A; Cooper, Ashley R; Rudolf, Mary

    2011-01-01

    Background In the evaluation of childhood obesity interventions, few researchers undertake a rigorous feasibility stage in which the design and procedures of the evaluation process are examined. Consequently, phase III studies often demonstrate methodological weaknesses. Purpose Our aim was to conduct a feasibility trial of the evaluation of WATCH IT, a community obesity intervention for children and adolescents. We sought to determine an achievable recruitment rate; acceptability of randomisation, assessment procedures, and dropout rate; optimal outcome measures for the definitive trial; and a robust sample size calculation. Method Our goal was to recruit 70 participants over 6 months, randomise them to intervention or control group, and retain participation for 12 months. Assessments were taken prior to randomisation and after 6 and 12 months. Procedures mirrored those intended for a full-scale trial, but multiple measures of similar outcomes were included as a means to determine those most appropriate for future research. Acceptability of the research and impact of the research on the programme were ascertained through interviewing participants and staff. Results We recruited 70 participants and found that randomisation and data collection procedures were acceptable. Self-referral (via media promotion) was more effective than professional referral. Blinding of assessors was sustained to a reasonable degree, and optimal outcome measures for a full-scale trial were identified. Estimated sample size was significantly greater than sample sized reported in published trials. There was some negative impact on the existing programme as a result of the research, a lesson for designers of future trials. Limitations We successfully recruited socially disadvantaged families, but the majority of families were of White British nationality. The composition of the participants was an added valuable lesson, suggesting that recruitment strategies to obtain a more heterogeneous

  12. Generalized internal model robust control for active front steering intervention

    NASA Astrophysics Data System (ADS)

    Wu, Jian; Zhao, Youqun; Ji, Xuewu; Liu, Yahui; Zhang, Lipeng

    2015-03-01

    Because of the tire nonlinearity and vehicle's parameters' uncertainties, robust control methods based on the worst cases, such as H ∞, µ synthesis, have been widely used in active front steering control, however, in order to guarantee the stability of active front steering system (AFS) controller, the robust control is at the cost of performance so that the robust controller is a little conservative and has low performance for AFS control. In this paper, a generalized internal model robust control (GIMC) that can overcome the contradiction between performance and stability is used in the AFS control. In GIMC, the Youla parameterization is used in an improved way. And GIMC controller includes two sections: a high performance controller designed for the nominal vehicle model and a robust controller compensating the vehicle parameters' uncertainties and some external disturbances. Simulations of double lane change (DLC) maneuver and that of braking on split- µ road are conducted to compare the performance and stability of the GIMC control, the nominal performance PID controller and the H ∞ controller. Simulation results show that the high nominal performance PID controller will be unstable under some extreme situations because of large vehicle's parameters variations, H ∞ controller is conservative so that the performance is a little low, and only the GIMC controller overcomes the contradiction between performance and robustness, which can both ensure the stability of the AFS controller and guarantee the high performance of the AFS controller. Therefore, the GIMC method proposed for AFS can overcome some disadvantages of control methods used by current AFS system, that is, can solve the instability of PID or LQP control methods and the low performance of the standard H ∞ controller.

  13. To condition or not condition? Analysing ‘change’ in longitudinal randomised controlled trials

    PubMed Central

    Coffman, Cynthia J; Edelman, David; Woolson, Robert F

    2016-01-01

    Objective The statistical analysis for a 2-arm randomised controlled trial (RCT) with a baseline outcome followed by a few assessments at fixed follow-up times typically invokes traditional analytic methods (eg, analysis of covariance (ANCOVA), longitudinal data analysis (LDA)). ‘Constrained’ longitudinal data analysis (cLDA) is a well-established unconditional technique that constrains means of baseline to be equal between arms. We use an analysis of fasting lipid profiles from the Group Medical Clinics (GMC) longitudinal RCT on patients with diabetes to illustrate applications of ANCOVA, LDA and cLDA to demonstrate theoretical concepts of these methods including the impact of missing data. Methods For the analysis of the illustrated example, all models were fit using linear mixed models to participants with only complete data and to participants using all available data. Results With complete data (n=195), 95% CI coverage are equivalent for ANCOVA and cLDA with an estimated 11.2 mg/dL (95% CI −19.2 to −3.3; p=0.006) lower mean low-density lipoprotein (LDL) cholesterol in GMC compared with usual care. With all available data (n=233), applying the cLDA model yielded an LDL improvement of 8.9 mg/dL (95% CI −16.7 to −1.0; p=0.03) for GMC compared with usual care. The less efficient, LDA analysis yielded an LDL improvement of 7.2 mg/dL (95% CI −17.2 to 2.8; p=0.15) for GMC compared with usual care. Conclusions Under reasonable missing data assumptions, cLDA will yield efficient treatment effect estimates and robust inferential statistics. It may be regarded as the method of choice over ANCOVA and LDA. PMID:28039292

  14. Angioplasty and stenting for patients with symptomatic intracranial atherosclerosis: study protocol of a randomised controlled trial

    PubMed Central

    Cui, Xiao-Ping; Lin, Min; Mu, Jun-Shan; Ye, Jian-Xin; He, Wen-Qing; Fu, Mao-Lin; Li, Hua; Fang, Jia-Yang; Shen, Feng-Feng; Lin, Hang

    2016-01-01

    Introduction Whether adding percutaneous transluminal angioplasty and stenting (PTAS) to background medical treatment is effective for decreasing the incidence of stroke or death in patients with symptomatic intracranial atherosclerosis (ICAS) is still controversial. We perform a randomised controlled trial to examine the effectiveness and safety of an improved PTAS procedure for patients with ICAS. Methods and analysis A randomised controlled trial will be conducted in three hospitals in China. Eligible patients with ICAS will be randomly assigned to receive medication treatment (MT) plus PTAS or MT alone. The MT will be initiated immediately after randomisation, while the PTAS will be performed when patients report relief of alarm symptoms defined as sudden weakness or numbness. All patients will be followed up at 30 days, 3 and 12 months after randomisation. The primary end point will be the incidence of stroke or death at 30 days after randomisation. Secondary outcomes will be the incidence of ischaemic stroke in the territory of stenosis arteries, the incidence of in-stent restenosis, the Chinese version of the modified Rankin Scale and the Chinese version of the Stroke-Specific Quality of Life (CSQoL). Ethics and dissemination The study protocol is approved by institutional review boards in participating hospitals (reference number FZ20160003, 180PLA20160101 and 476PLA2016007). The results of this study will be disseminated to patients, physicians and policymakers through publication in a peer-reviewed journal or presentations in conferences. It is anticipated that the results of this study will improve the quality of the current PTAS procedure and guide clinical decision-making for patients with ICAS. Trial registration number NCT02689037 PMID:27852711

  15. Robustness results in LQG based multivariable control designs

    NASA Technical Reports Server (NTRS)

    Lehtomaki, N. A.; Sandell, N. R., Jr.; Athans, M.

    1980-01-01

    The robustness of control systems with respect to model uncertainty is considered using simple frequency domain criteria. Results are derived under a common framework in which the minimum singular value of the return difference transfer matrix is the key quantity. In particular, the LQ and LQG robustness results are discussed.

  16. Robust on-off pulse control of flexible space vehicles

    NASA Technical Reports Server (NTRS)

    Wie, Bong; Sinha, Ravi

    1993-01-01

    The on-off reaction jet control system is often used for attitude and orbital maneuvering of various spacecraft. Future space vehicles such as the orbital transfer vehicles, orbital maneuvering vehicles, and space station will extensively use reaction jets for orbital maneuvering and attitude stabilization. The proposed robust fuel- and time-optimal control algorithm is used for a three-mass spacing model of flexible spacecraft. A fuel-efficient on-off control logic is developed for robust rest-to-rest maneuver of a flexible vehicle with minimum excitation of structural modes. The first part of this report is concerned with the problem of selecting a proper pair of jets for practical trade-offs among the maneuvering time, fuel consumption, structural mode excitation, and performance robustness. A time-optimal control problem subject to parameter robustness constraints is formulated and solved. The second part of this report deals with obtaining parameter insensitive fuel- and time- optimal control inputs by solving a constrained optimization problem subject to robustness constraints. It is shown that sensitivity to modeling errors can be significantly reduced by the proposed, robustified open-loop control approach. The final part of this report deals with sliding mode control design for uncertain flexible structures. The benchmark problem of a flexible structure is used as an example for the feedback sliding mode controller design with bounded control inputs and robustness to parameter variations is investigated.

  17. Probability-based stability robustness assessment of controlled structures

    SciTech Connect

    Field, R.V. Jr.; Voulgaris, P.G.; Bergman, L.A.

    1996-01-01

    Model uncertainty, if ignored, can seriously degrade the performance of an otherwise well-designed control system. If the level of this uncertainty is extreme, the system may even be driven to instability. In the context of structural control, performance degradation and instability imply excessive vibration or even structural failure. Robust control has typically been applied to the issue of model uncertainty through worst-case analyses. These traditional methods include the use of the structured singular value, as applied to the small gain condition, to provide estimates of controller robustness. However, this emphasis on the worst-case scenario has not allowed a probabilistic understanding of robust control. In this paper an attempt to view controller robustness as a probability measure is presented. The probability of failure due to parametric uncertainty is estimated using first-order reliability methods (FORM). It is demonstrated that this method can provide quite accurate results on the probability of failure of actively controlled structures. Moreover, a comparison of this method to a suitability modified structured singular value robustness analysis in a probabilistic framework is performed. It is shown that FORM is the superior analysis technique when applied to a controlled three degree-of-freedom structure. In addition, the robustness qualities of various active control design schemes such as LQR, H{sub 2}, H {sub oo}, and {mu}-synthesis is discussed in order to provide some design guidelines.

  18. High-performance quantitative robust switching control for optical telescopes

    NASA Astrophysics Data System (ADS)

    Lounsbury, William P.; Garcia-Sanz, Mario

    2014-07-01

    This paper introduces an innovative robust and nonlinear control design methodology for high-performance servosystems in optical telescopes. The dynamics of optical telescopes typically vary according to azimuth and altitude angles, temperature, friction, speed and acceleration, leading to nonlinearities and plant parameter uncertainty. The methodology proposed in this paper combines robust Quantitative Feedback Theory (QFT) techniques with nonlinear switching strategies that achieve simultaneously the best characteristics of a set of very active (fast) robust QFT controllers and very stable (slow) robust QFT controllers. A general dynamic model and a variety of specifications from several different commercially available amateur Newtonian telescopes are used for the controller design as well as the simulation and validation. It is also proven that the nonlinear/switching controller is stable for any switching strategy and switching velocity, according to described frequency conditions based on common quadratic Lyapunov functions (CQLF) and the circle criterion.

  19. Closed-Loop and Robust Control of Quantum Systems

    PubMed Central

    Wang, Lin-Cheng

    2013-01-01

    For most practical quantum control systems, it is important and difficult to attain robustness and reliability due to unavoidable uncertainties in the system dynamics or models. Three kinds of typical approaches (e.g., closed-loop learning control, feedback control, and robust control) have been proved to be effective to solve these problems. This work presents a self-contained survey on the closed-loop and robust control of quantum systems, as well as a brief introduction to a selection of basic theories and methods in this research area, to provide interested readers with a general idea for further studies. In the area of closed-loop learning control of quantum systems, we survey and introduce such learning control methods as gradient-based methods, genetic algorithms (GA), and reinforcement learning (RL) methods from a unified point of view of exploring the quantum control landscapes. For the feedback control approach, the paper surveys three control strategies including Lyapunov control, measurement-based control, and coherent-feedback control. Then such topics in the field of quantum robust control as H∞ control, sliding mode control, quantum risk-sensitive control, and quantum ensemble control are reviewed. The paper concludes with a perspective of future research directions that are likely to attract more attention. PMID:23997680

  20. Robust tuning of robot control systems

    NASA Technical Reports Server (NTRS)

    Minis, I.; Uebel, M.

    1992-01-01

    The computed torque control problem is examined for a robot arm with flexible, geared, joint drive systems which are typical in many industrial robots. The standard computed torque algorithm is not directly applicable to this class of manipulators because of the dynamics introduced by the joint drive system. The proposed approach to computed torque control combines a computed torque algorithm with torque controller at each joint. Three such control schemes are proposed. The first scheme uses the joint torque control system currently implemented on the robot arm and a novel form of the computed torque algorithm. The other two use the standard computed torque algorithm and a novel model following torque control system based on model following techniques. Standard tasks and performance indices are used to evaluate the performance of the controllers. Both numerical simulations and experiments are used in evaluation. The study shows that all three proposed systems lead to improved tracking performance over a conventional PD controller.

  1. Randomised controlled trial of cisapride in preterm infants

    PubMed Central

    McClure, R; Kristensen, J; Grauaug, A

    1999-01-01

    AIM—To determine the effect of cisapride on gastrointestinal motility in preterm infants.
METHODS—Cisapride (0.2 mg/kg, 8 hourly ) or placebo was given first for seven days in a double blind randomised crossover study of 10 preterm infants. Gastrointestinal motility was assessed on day 3 of each treatment. The half gastric emptying time (GET1/2) was determined by using ultrasonography to measure the decrease in the gastric antral cross sectional area after a feed. The whole gastrointestinal transit time (WGTT) was assessed by timing the transit of carmine red through the gut. Treatments were compared using the Wilcoxon matched pairs signed ranks test.
RESULTS—Median (range) birthweight was 1200 (620, 1450) g and postconceptional age 33 (29, 34) weeks at recruitment. GET1/2 was significantly longer during cisapride treatment than during placebo; the median of the differences (95% confidence interval) was 19.2 (11, 30minutes, p=0.008). WGTT was also longer during cisapride treatment, but the difference was not significant; the median of the differences was 11(−18, 52 hours, p=0.1).
CONCLUSIONS—Cisapride delays gastric emptying and may delay WGTT in preterm infants. Its use to promote gastrointestinal motility in this group cannot be recommended.

 PMID:10212076

  2. A Robustly Stabilizing Model Predictive Control Algorithm

    NASA Technical Reports Server (NTRS)

    Ackmece, A. Behcet; Carson, John M., III

    2007-01-01

    A model predictive control (MPC) algorithm that differs from prior MPC algorithms has been developed for controlling an uncertain nonlinear system. This algorithm guarantees the resolvability of an associated finite-horizon optimal-control problem in a receding-horizon implementation.

  3. Robust Nonlinear Control of Tailless Fighter Aircraft

    DTIC Science & Technology

    1999-02-01

    adaptive backstepping and nonlinear PI control , it is not very straightforward to establish this uniform asymptotic stability (in a set of error coordinates...tracking error coordinates for mechanical systems and ships controlled via adaptive back- stepping and nonlinear PI control algorithms. These results were

  4. Association between bibliometric parameters, reporting and methodological quality of randomised controlled trials in vascular and endovascular surgery.

    PubMed

    Hajibandeh, Shahab; Hajibandeh, Shahin; Antoniou, George A; Green, Patrick A; Maden, Michelle; Torella, Francesco

    2017-04-01

    Purpose We aimed to investigate association between bibliometric parameters, reporting and methodological quality of vascular and endovascular surgery randomised controlled trials. Methods The most recent 75 and oldest 75 randomised controlled trials published in leading journals over a 10-year period were identified. The reporting quality was analysed using the CONSORT statement, and methodological quality with the Intercollegiate Guidelines Network checklist. We used exploratory univariate and multivariable linear regression analysis to investigate associations. Findings Bibliometric parameters such as type of journal, study design reported in title, number of pages; external funding, industry sponsoring and number of citations are associated with reporting quality. Moreover, parameters such as type of journal, subject area and study design reported in title are associated with methodological quality. Conclusions The bibliometric parameters of randomised controlled trials may be independent predictors for their reporting and methodological quality. Moreover, the reporting quality of randomised controlled trials is associated with their methodological quality and vice versa.

  5. Robust and reconfigurable flight control system design

    NASA Astrophysics Data System (ADS)

    Siwakosit, Wichai

    2001-07-01

    A reconfigurable flight control system is a control system which can automatically adapt itself to maintain the performance of a damaged aircraft to be as close as possible to that of the normal or undamaged one. This research focuses mainly on Multi-Input, Multi-Output (MIMO) reconfigurable flight control for an aircraft with damaged actuator(s) which may greatly affect the performance and control of the aircraft, and also pose a challenging flight control problem. The foundation of the control system is a baseline controller and an adaptive module which constitutes a reconfigurable part. The baseline controller ensures that the aircraft has acceptable performance and handling qualities throughout the flight envelope. The combination of a Quantitative Feedback Theory (QFT) Pre-Design Technique (PDT) and a Reduced-order, Linear, Dynamic Inversion (RLDI) control strategy yields a flight control system with good tracking performance and handling qualities with no Pilot Induced Oscillation (PIO) tendencies throughout the designated set of flight conditions. In addition, the system is highly immune to large uncertainties in the aircraft dynamics. The modified filtered-ɛ adaptive algorithm is developed and utilized in the adaptive module of the system. This adaptive algorithm performs well with MIMO system with the added advantage of not having to pre-identify the dynamics of the damaged aircraft, provided that the conditions of reconfigurability are met. An example of the proposed control system with the NASA F-18 HARV vehicle model and a damaged actuator demonstrates the effectiveness of the concept.

  6. Randomised controlled trial to evaluate early discharge scheme for patients with stroke.

    PubMed Central

    Rudd, A. G.; Wolfe, C. D.; Tilling, K.; Beech, R.

    1997-01-01

    OBJECTIVE: To assess the clinical effectiveness of an early discharge policy for patients with stroke by using a community based rehabilitation team. DESIGN: Randomised controlled trial to compare conventional care with an early discharge policy. SETTING: Two teaching hospitals in inner London. SUBJECTS: 331 medically stable patients with stroke (mean age 71) who lived alone and were able to transfer independently or who lived with a resident carer and were able to transfer with help. INTERVENTIONS: 167 patients received specialist community rehabilitation for up to 3 months after randomisation. 164 patients continued with conventional hospital and community care. MAIN OUTCOME MEASURES: Barthel score at 12 months. Secondary outcomes measured impairment with motoricity index, minimental state examination, and Frenchay aphasia screening test; disability with the Rivermead activity of daily living scales, hospital anxiety and depression scale, and 5 m walk; handicap with the Nottingham health profile; carer stress with caregiver strain index and patient and carer satisfaction. The main process measure was length of stay after randomisation. RESULTS: One year after randomisation no significant differences in clinical outcomes were found apart from increased satisfaction with hospital care in the community therapy group. Length of stay after randomisation in the community therapy group was significantly reduced (12 v 18 days; P < 0.0001). Patients with impairments were more likely to receive treatment in the community therapy group. CONCLUSIONS: Early discharge with specialist community rehabilitation after stroke is feasible, as clinically effective as conventional care, and acceptable to patients. Considerable reductions in use of hospital beds are achievable. PMID:9366727

  7. Modern CACSD using the Robust-Control Toolbox

    NASA Technical Reports Server (NTRS)

    Chiang, Richard Y.; Safonov, Michael G.

    1989-01-01

    The Robust-Control Toolbox is a collection of 40 M-files which extend the capability of PC/PRO-MATLAB to do modern multivariable robust control system design. Included are robust analysis tools like singular values and structured singular values, robust synthesis tools like continuous/discrete H(exp 2)/H infinity synthesis and Linear Quadratic Gaussian Loop Transfer Recovery methods and a variety of robust model reduction tools such as Hankel approximation, balanced truncation and balanced stochastic truncation, etc. The capabilities of the toolbox are described and illustated with examples to show how easily they can be used in practice. Examples include structured singular value analysis, H infinity loop-shaping and large space structure model reduction.

  8. Vehicle active steering control research based on two-DOF robust internal model control

    NASA Astrophysics Data System (ADS)

    Wu, Jian; Liu, Yahui; Wang, Fengbo; Bao, Chunjiang; Sun, Qun; Zhao, Youqun

    2016-07-01

    Because of vehicle's external disturbances and model uncertainties, robust control algorithms have obtained popularity in vehicle stability control. The robust control usually gives up performance in order to guarantee the robustness of the control algorithm, therefore an improved robust internal model control(IMC) algorithm blending model tracking and internal model control is put forward for active steering system in order to reach high performance of yaw rate tracking with certain robustness. The proposed algorithm inherits the good model tracking ability of the IMC control and guarantees robustness to model uncertainties. In order to separate the design process of model tracking from the robustness design process, the improved 2 degree of freedom(DOF) robust internal model controller structure is given from the standard Youla parameterization. Simulations of double lane change maneuver and those of crosswind disturbances are conducted for evaluating the robust control algorithm, on the basis of a nonlinear vehicle simulation model with a magic tyre model. Results show that the established 2-DOF robust IMC method has better model tracking ability and a guaranteed level of robustness and robust performance, which can enhance the vehicle stability and handling, regardless of variations of the vehicle model parameters and the external crosswind interferences. Contradiction between performance and robustness of active steering control algorithm is solved and higher control performance with certain robustness to model uncertainties is obtained.

  9. Robust control of photoassociation of slow O + H collision

    NASA Astrophysics Data System (ADS)

    Zhang, Wei; Dong, Daoyi; Petersen, Ian R.; Rabitz, Herschel A.

    2017-02-01

    We show that robust laser pulses can be obtained by a sampling-based method to achieve a desired photoassociation probability when uncertainties in potential curves and laser amplitudes are considered. Optimal control simulations are performed using a time-dependent wave packet method based on a single electronic state. We use a small number of samples to construct a robust field and test the performance of this field using additional samples. Excellent outcomes are obtained based on the proposed method for different uncertainties. The robust control field achieves higher average photoassociation probabilities over the tested samples, in comparison with the probabilities achieved by the optimal field designed without using the sampling-based method. The sampling-based method may also be promising in the robust control of other molecular control goals.

  10. Computation of robustly stabilizing PID controllers for interval systems.

    PubMed

    Matušů, Radek; Prokop, Roman

    2016-01-01

    The paper is focused on the computation of all possible robustly stabilizing Proportional-Integral-Derivative (PID) controllers for plants with interval uncertainty. The main idea of the proposed method is based on Tan's (et al.) technique for calculation of (nominally) stabilizing PI and PID controllers or robustly stabilizing PI controllers by means of plotting the stability boundary locus in either P-I plane or P-I-D space. Refinement of the existing method by consideration of 16 segment plants instead of 16 Kharitonov plants provides an elegant and efficient tool for finding all robustly stabilizing PID controllers for an interval system. The validity and relatively effortless application of presented theoretical concepts are demonstrated through a computation and simulation example in which the uncertain mathematical model of an experimental oblique wing aircraft is robustly stabilized.

  11. Pupil Control Behavior, Classroom Robustness, and Self-Control: Public and Military High Schools Compared.

    ERIC Educational Resources Information Center

    Sartori, Mary Ann; Bauske, Terri; Lunenburg, Fred C.

    This study investigates students' perceptions of teachers' pupil control behavior, classroom robustness, and student self-control. Results reveal an association between humanistic pupil control behavior of teachers and high levels of classroom robustness, high levels of classroom robustness and high student self-control, and teacher humanism in…

  12. Practical Methods for Robust Multivariable Control

    DTIC Science & Technology

    1991-12-31

    objectives in the face of both structured and unstructured uncertainty. Advances in the past two years have included relative-error methods for system ... identification , model reduction and control, better algorithms for H- and H2 control computations and new results on the analysis of stability

  13. Robust Adaptive Control of Multivariable Nonlinear Systems

    DTIC Science & Technology

    2011-03-28

    Systems: Challenge Problem Integration and NASA s Integrated Resilient Aircraft Control . We also revealed some similarities with the disturbance ... observer (DOB) controllers and identified the main features in the difference between them. The key feature of this difference is that the estimation loop

  14. Panaceas, uncertainty, and the robust control framework in sustainability science

    PubMed Central

    Anderies, John M.; Rodriguez, Armando A.; Janssen, Marco A.; Cifdaloz, Oguzhan

    2007-01-01

    A critical challenge faced by sustainability science is to develop strategies to cope with highly uncertain social and ecological dynamics. This article explores the use of the robust control framework toward this end. After briefly outlining the robust control framework, we apply it to the traditional Gordon–Schaefer fishery model to explore fundamental performance–robustness and robustness–vulnerability trade-offs in natural resource management. We find that the classic optimal control policy can be very sensitive to parametric uncertainty. By exploring a large class of alternative strategies, we show that there are no panaceas: even mild robustness properties are difficult to achieve, and increasing robustness to some parameters (e.g., biological parameters) results in decreased robustness with respect to others (e.g., economic parameters). On the basis of this example, we extract some broader themes for better management of resources under uncertainty and for sustainability science in general. Specifically, we focus attention on the importance of a continual learning process and the use of robust control to inform this process. PMID:17881574

  15. Metacognitive training for schizophrenia: a multicentre randomised controlled trial.

    PubMed

    Briki, Malick; Monnin, Julie; Haffen, Emmanuel; Sechter, Daniel; Favrod, Jérôme; Netillard, Christian; Cheraitia, Elisabeth; Marin, Karine; Govyadovskaya, Svetlana; Tio, Grégory; Bonin, Bernard; Chauvet-Gelinier, Jean-Christophe; Leclerc, Stéphanie; Hodé, Yann; Vidailhet, Pierre; Berna, Fabrice; Bertschy, Anna Zinetti; Vandel, Pierre

    2014-08-01

    A psychotherapeutic approach for schizophrenia is now recommended as an adjuvant for psychopharmacology, since antipsychotic medications only have a partial impact especially as regards positive symptoms and insight. In addition, cognitive distortions and the lack of metacognitive skills might increase positive symptoms leading to poor social functioning. This underlines the need for specific approaches which target cognitive processes relevant for insight, and abilities in metacognition. Metacognitive training (MCT) is a structured group intervention, which enhances a patient's reflection on cognitive biases and improves problem-solving. The aim of our study was to assess MCTs' short term impact on insight, symptoms and quality of life. Fifty patients with schizophrenia or schizoaffective disorders and persistent positive symptoms (delusions or hallucinations) were enrolled in the study. After baseline assessment participants were randomised either to supportive therapy or MCT. Both groups used the same design (1h-session twice a week during 8weeks) although the basic knowledge given to participants was different between interventions. Participants were assessed at eight weeks based on the Scale to Assess Unawareness of Mental Disorder, Positive and Negative Syndrome Scale (PANSS), Psychotic Symptom Rating Scales, the Calgary Depression Scale for Schizophrenia and the Quality of Life Scale. Between-group differences were significant in favour of MCT on the PANSS positive scale. Between-group differences in post- and pre-test values showed a trend in favour of MCT for insight on hallucinations. Results of our study indicate that the MCT has an effect on reducing positive symptomatology, and a trend impact on insight and social functioning.

  16. Chinese Obstetrics & Gynecology journal club: a randomised controlled trial

    PubMed Central

    Tsui, Ilene K; Dodson, William C; Kunselman, Allen R; Kuang, Hongying; Han, Feng-Juan; Legro, Richard S; Wu, Xiao-Ke

    2016-01-01

    Objectives To assess whether a journal club model could improve comprehension and written and spoken medical English in a population of Chinese medical professionals. Setting and participants The study population consisted of 52 medical professionals who were residents or postgraduate master or PhD students in the Department of Obstetrics and Gynecology, Heilongjiang University of Chinese Medicine, China. Intervention After a three-part baseline examination to assess medical English comprehension, participants were randomised to either (1) an intensive journal club treatment arm or (2) a self-study group. At the conclusion of the 8-week intervention participants (n=52) were re-tested with new questions. Outcome measures The primary outcome was the change in score on a multiple choice examination. Secondary outcomes included change in scores on written and oral examinations which were modelled on the Test of English as a Foreign Language (TOEFL). Results Both groups had improved scores on the multiple choice examination without a statistically significant difference between them (90% power). However, there was a statistically significant difference between the groups in mean improvement in scores for both written (95% CI 1.1 to 5.0; p=0.003) and spoken English (95% CI 0.06 to 3.7; p=0.04) favouring the journal club intervention. Conclusions Interacting with colleagues and an English-speaking facilitator in a journal club improved both written and spoken medical English in Chinese medical professionals. Journal clubs may be suitable for use as a self-sustainable teaching model to improve fluency in medical English in foreign medical professionals. Trial registration number NCT01844609. PMID:26823180

  17. Randomised controlled trial of topical kanuka honey for the treatment of acne

    PubMed Central

    Semprini, Alex; Corin, Andrew; Sheahan, Davitt; Tofield, Christopher; Helm, Colin; Montgomery, Barney; Fingleton, James; Weatherall, Mark; Beasley, Richard

    2016-01-01

    Objective To investigate the efficacy of Honevo, a topical 90% medical-grade kanuka honey, and 10% glycerine (honey product) as a treatment for facial acne. Design Randomised controlled trial with single blind assessment of primary outcome variable. Setting Outpatient primary care from 3 New Zealand localities. Participants Of 136 participants aged between 16 and 40 years with a diagnosis of acne and baseline Investigator's Global Assessment (IGA) for acne score of ≥2.68, participants were randomised to each treatment arm. Interventions All participants applied Protex, a triclocarban-based antibacterial soap twice daily for 12 weeks. Participants randomised to the honey product treatment arm applied this directly after washing off the antibacterial soap, twice daily for 12 weeks. Outcome measures The primary outcome was ≥2 point decrease in IGA score from baseline at 12 weeks. Secondary outcomes included mean lesion counts and changes in subject-rated acne improvement and severity at weeks 4 and 12, and withdrawals for worsening acne. Results 4/53 (7.6%) participants in the honey product group and 1/53 (1.9%) of participants in the control group had a ≥ 2 improvement in IGA score at week 12, compared with baseline, OR (95% CI) for improvement 4.2 (0.5 to 39.3), p=0.17. There were 15 and 14 participants who withdrew from the honey product group and control group, respectively. Conclusions This randomised controlled trial did not find evidence that addition of medical-grade kanuka honey in combination with 10% glycerine to standard antibacterial soap treatment is more effective than the use of antibacterial soap alone in the treatment of acne. Trial registration number ACTRN12614000003673; Results. PMID:26832428

  18. Controlled quantum dialogue robust against conspiring users

    NASA Astrophysics Data System (ADS)

    Kao, Shih-Hung; Hwang, Tzonelih

    2016-10-01

    This paper explores a new security problem in controlled quantum dialogue (CQD) protocols, where the communicants may try to conspire to communicate without the controller's permission. According to our survey, all the previous CQD protocols suffer from this attack. In order to resolve this problem, we also present an improvement protocol. The security analyses show that the improved scheme is secure under this and other well-known attacks.

  19. Networked Robust Predictive Control Systems Design with Packet Loss

    NASA Astrophysics Data System (ADS)

    Nguyen, Quang T.; Veselý, Vojtech; Kozáková, Alena; Pakshin, Pavel

    2014-01-01

    The paper addresses problem of designing a robust output feedback model predictive control for uncertain linear systems over networks with packet-loss. The packet-loss process is arbitrary and bounded by the control horizon of model predictive control. Networked predictive control systems with packet loss are modeled as switched linear systems. This enables us to apply the theory of switched systems to establish the stability condition. The stabilizing controller design is based on sufficient robust stability conditions formulated as a solution of bilinear matrix inequality. Finally, a benchmark numerical example-double integrator is given to illustrate the effectiveness of the proposed method.

  20. Robust H∞ Control for Spacecraft Rendezvous with a Noncooperative Target

    PubMed Central

    Wu, Shu-Nan; Zhou, Wen-Ya; Tan, Shu-Jun; Wu, Guo-Qiang

    2013-01-01

    The robust H∞ control for spacecraft rendezvous with a noncooperative target is addressed in this paper. The relative motion of chaser and noncooperative target is firstly modeled as the uncertain system, which contains uncertain orbit parameter and mass. Then the H∞ performance and finite time performance are proposed, and a robust H∞ controller is developed to drive the chaser to rendezvous with the non-cooperative target in the presence of control input saturation, measurement error, and thrust error. The linear matrix inequality technology is used to derive the sufficient condition of the proposed controller. An illustrative example is finally provided to demonstrate the effectiveness of the controller. PMID:24027446

  1. Robust predictive cruise control for commercial vehicles

    NASA Astrophysics Data System (ADS)

    Junell, Jaime; Tumer, Kagan

    2013-10-01

    In this paper we explore learning-based predictive cruise control and the impact of this technology on increasing fuel efficiency for commercial trucks. Traditional cruise control is wasteful when maintaining a constant velocity over rolling hills. Predictive cruise control (PCC) is able to look ahead at future road conditions and solve for a cost-effective course of action. Model- based controllers have been implemented in this field but cannot accommodate many complexities of a dynamic environment which includes changing road and vehicle conditions. In this work, we focus on incorporating a learner into an already successful model- based predictive cruise controller in order to improve its performance. We explore back propagating neural networks to predict future errors then take actions to prevent said errors from occurring. The results show that this approach improves the model based PCC by up to 60% under certain conditions. In addition, we explore the benefits of classifier ensembles to further improve the gains due to intelligent cruise control.

  2. Design and tuning of robust PID controller for HVAC systems

    SciTech Connect

    Kasahara, Masato; Matsuba, Tadahiko; Kuzuu, Yoshiaki; Yamazaki, Takanori; Hashimoto, Yukihiro; Kamimura, Kazuyuki; Kurosu, Shigeru

    1999-07-01

    This paper concerns the development of a new design and tuning method for use with robust proportional-plus-integral-plus-derivative (PID) controllers that are commonly used in the heating, ventilating, and air-conditioning (HVAC) fields. The robust PID controller is designed for temperature control of a single-zone environmental space. Although the dynamics of environmental space are described by higher-order transfer functions, most HVAC plants are approximated by first-order lag plus deadtime systems. Its control performance is examined for this commonly approximated controlled plant. Since most HVAC plants are complex with nonlinearity, distributed parameters, and multivariables, a single set of PID gains does not necessarily yield a satisfactory control performance. For this reason, the PID controller must be designed as a robust control system considering model uncertainty caused by changes in characteristics of the plant. The PID gains obtained by solving a two-disk type of mixed sensitivity problem can be modified by contrast to those tuned by the traditional Ziegler-Nichols rule. The results, which are surprisingly simple, are given as linear functions of ratio of deadtime to time constant for robustness. The numerical simulation and the experiments on a commercial-size test plant for air conditioning suggest that the robust PID controller proposed in this paper is effective enough for practical applications.

  3. Social Stories in mainstream schools for children with autism spectrum disorder: a feasibility randomised controlled trial

    PubMed Central

    Marshall, David; Wright, Barry; Allgar, Victoria; Adamson, Joy; Williams, Christine; Ainsworth, Hannah; Cook, Liz; Varley, Danielle; Hackney, Lisa; Dempster, Paul; Ali, Shehzad; Trepel, Dominic; Collingridge Moore, Danielle; Littlewood, Elizabeth; McMillan, Dean

    2016-01-01

    Objectives To assess the feasibility of recruitment, retention, outcome measures and intervention training/delivery among teachers, parents and children. To calculate a sample size estimation for full trial. Design A single-centre, unblinded, cluster feasibility randomised controlled trial examining Social Stories delivered within a school environment compared with an attentional control. Setting 37 primary schools in York, UK. Participants 50 participants were recruited and a cluster randomisation approach by school was examined. Participants were randomised into the treatment group (n=23) or a waiting list control group (n=27). Outcome measures Acceptability and feasibility of the trial, intervention and of measurements required to assess outcomes in a definitive trial. Results An assessment of the questionnaire completion rates indicated teachers would be most appropriate to complete the primary outcome measure. 2 outcome measures: the Social Responsiveness Scale (SRS)-2 and a goal-based measure showed both the highest levels of completion rates (above 80%) at the primary follow-up point (6 weeks postintervention) and captured relevant social and behaviour outcomes. Power calculations were based on these 2 outcome measures leading to a total proposed sample size of 180 participant groups. Conclusions Results suggest that a future trial would be feasible to conduct and could inform the policy and practice of using Social Stories in mainstream schools. Trial registration number ISRCTN96286707; Results. PMID:27515756

  4. Maximising the impact of qualitative research in feasibility studies for randomised controlled trials: guidance for researchers.

    PubMed

    O'Cathain, Alicia; Hoddinott, Pat; Lewin, Simon; Thomas, Kate J; Young, Bridget; Adamson, Joy; Jansen, Yvonne Jfm; Mills, Nicola; Moore, Graham; Donovan, Jenny L

    2015-01-01

    Feasibility studies are increasingly undertaken in preparation for randomised controlled trials in order to explore uncertainties and enable trialists to optimise the intervention or the conduct of the trial. Qualitative research can be used to examine and address key uncertainties prior to a full trial. We present guidance that researchers, research funders and reviewers may wish to consider when assessing or undertaking qualitative research within feasibility studies for randomised controlled trials. The guidance consists of 16 items within five domains: research questions, data collection, analysis, teamwork and reporting. Appropriate and well conducted qualitative research can make an important contribution to feasibility studies for randomised controlled trials. This guidance may help researchers to consider the full range of contributions that qualitative research can make in relation to their particular trial. The guidance may also help researchers and others to reflect on the utility of such qualitative research in practice, so that trial teams can decide when and how best to use these approaches in future studies.

  5. Robust Control of Underactuated Manipulators: Analysis and Implementation

    DTIC Science & Technology

    1994-05-01

    Y Control of mechanical systems with second-order nonholonomic constraints: underactuated manipulators. Proc. of the 30th Conference on Decision and...any of a series of controllers fully developed in the literature for mechanical manipulators. Because the control of such a system is fully dependent...robust controller for underactuated manipulators. The control of such systems can be extended to the control problem of fault-tolerant robots, space

  6. A novel robust speed controller scheme for PMBLDC motor.

    PubMed

    Thirusakthimurugan, P; Dananjayan, P

    2007-10-01

    The design of speed and position controllers for permanent magnet brushless DC motor (PMBLDC) drive remains as an open problem in the field of motor drives. A precise speed control of PMBLDC motor is complex due to nonlinear coupling between winding currents and rotor speed. In addition, the nonlinearity present in the developed torque due to magnetic saturation of the rotor further complicates this issue. This paper presents a novel control scheme to the conventional PMBLDC motor drive, which aims at improving the robustness by complete decoupling of the design besides minimizing the mutual influence among the speed and current control loops. The interesting feature of this robust control scheme is its suitability for both static and dynamic aspects. The effectiveness of the proposed robust speed control scheme is verified through simulations.

  7. Robust Control for the Mercury Laser Altimeter

    NASA Technical Reports Server (NTRS)

    Rosenberg, Jacob S.

    2006-01-01

    Mercury Laser Altimeter Science Algorithms is a software system for controlling the laser altimeter aboard the Messenger spacecraft, which is to enter into orbit about Mercury in 2011. The software will control the altimeter by dynamically modifying hardware inputs for gain, threshold, channel-disable flags, range-window start location, and range-window width, by using ranging information provided by the spacecraft and noise counts from instrument hardware. In addition, because of severe bandwidth restrictions, the software also selects returns for downlink.

  8. Robust control-based object tracking.

    PubMed

    Qu, Wei; Schonfeld, Dan

    2008-09-01

    This correspondence presents a video tracking framework using control-based observer design. It unifies several kernel-based approaches into a consistent theoretical framework by modeling tracking as a recursive inverse problem. The framework relies on observability theory to handle the "singularity" problem and provides explicit criteria for kernel design and dynamics evaluation.

  9. Stable, Robust Tracking by Sliding Mode Control,

    DTIC Science & Technology

    1987-05-01

    Linear Systems , Prentice-Hall, 1980. 9. O.M.E. El-Ghesawi, S.A. Billings and A.S.I. Zinober, Variable structure systems and system zeros, Proc. IEE...82, January 1987. 7. G.C. Verghese and T. Kailath, Rational matrix structure, IEEE Trans. Auto. Control, AC-26, 434-438, April 1981. 8. T. Kailath

  10. Quantitative Robust Control Engineering: Theory and Applications

    DTIC Science & Technology

    2006-09-01

    1992). Discrete quantitative feedback technique, Capítulo 16 en el libro : Digital Control Systems: theory, hardware, software, 2ª edicion. McGraw...Rasmussen S.J., Garcia-Sanz, M. (2001, 2005), Software de diseño del libro Quantitative Feedback Theory: Fundamentals and Applications. Edición 2ª. CRCPress

  11. Gut-directed hypnotherapy for irritable bowel syndrome: piloting a primary care-based randomised controlled trial

    PubMed Central

    Roberts, Lesley; Wilson, Sue; Singh, Sukhdev; Roalfe, Andrea; Greenfield, Sheila

    2006-01-01

    Background In western populations irritable bowel syndrome (IBS) affects between 10% and 30% of the population and has a significant effect on quality of life. It generates a substantial workload in both primary and secondary care and has significant cost implications. Gut-directed hypnotherapy has been demonstrated to alleviate symptoms and improve quality of life but has not been assessed outside of secondary and tertiary referral centres. Aim To assess the effectiveness of gut-directed hypnotherapy as a complementary therapy in the management of IBS. Design of study Randomised controlled trial. Setting Primary care patients aged 18–65 years inclusive, with a diagnosis of IBS of greater than 6 weeks' duration and having failed conventional management, located in South Staffordshire and North Birmingham, UK. Method Intervention patients received five sessions of hypnotherapy in addition to their usual management. Control patients received usual management alone. Data regarding symptoms and quality of life were collected at baseline and again 3, 6, and 12 months post-randomisation. Results Both groups demonstrated a significant improvement in all symptom dimensions and quality of life over 12 months. At 3 months the intervention group had significantly greater improvements in pain, diarrhoea and overall symptom scores (P<0.05). No significant differences between groups in quality of life were identified. No differences were maintained over time. Intervention patients, however, were significantly less likely to require medication, and the majority described an improvement in their condition. Conclusions Gut-directed hypnotherapy benefits patients via symptom reduction and reduced medication usage, although the lack of significant difference between groups beyond 3 months prohibits its general introduction without additional evidence. A large trial incorporating robust economic analysis is, therefore, urgently recommended. PMID:16464325

  12. Homoeopathy for delayed onset muscle soreness: a randomised double blind placebo controlled trial.

    PubMed Central

    Vickers, A J; Fisher, P; Smith, C; Wyllie, S E; Lewith, G T

    1997-01-01

    OBJECTIVE: To pilot a model for determining whether a homoeopathic medicine is superior to placebo for delayed onset muscle soreness (DOMS). DESIGN: Randomised double blind placebo controlled trial. SETTING: Physiotherapy department of a homoeopathic hospital. SUBJECTS: Sixty eight healthy volunteers (average age 30; 41% men) undertook a 10 minute period of bench stepping carrying a small weight and were randomised to a homoeopathic medicine or placebo. OUTCOME MEASURES: Mean muscle soreness in the five day period after the exercise test, symptom free days, maximum soreness score, days to no soreness, days on medication. RESULTS: The difference between group means was 0.17 in favour of placebo with 95% confidence intervals +/- 0.50. Similar results were found for other outcome measures. CONCLUSION: The study did not find benefit of the homoeopathic remedy in DOMS. Bench stepping may not be an appropriate model to evaluate the effects of a treatment on DOMS because of wide variation between subject soreness scores. PMID:9429007

  13. A Robust Control Design Framework for Substructure Models

    NASA Technical Reports Server (NTRS)

    Lim, Kyong B.

    1994-01-01

    A framework for designing control systems directly from substructure models and uncertainties is proposed. The technique is based on combining a set of substructure robust control problems by an interface stiffness matrix which appears as a constant gain feedback. Variations of uncertainties in the interface stiffness are treated as a parametric uncertainty. It is shown that multivariable robust control can be applied to generate centralized or decentralized controllers that guarantee performance with respect to uncertainties in the interface stiffness, reduced component modes and external disturbances. The technique is particularly suited for large, complex, and weakly coupled flexible structures.

  14. Robust adaptive kinematic control of redundant robots

    NASA Technical Reports Server (NTRS)

    Tarokh, M.; Zuck, D. D.

    1992-01-01

    The paper presents a general method for the resolution of redundancy that combines the Jacobian pseudoinverse and augmentation approaches. A direct adaptive control scheme is developed to generate joint angle trajectories for achieving desired end-effector motion as well as additional user defined tasks. The scheme ensures arbitrarily small errors between the desired and the actual motion of the manipulator. Explicit bounds on the errors are established that are directly related to the mismatch between actual and estimated pseudoinverse Jacobian matrix, motion velocity and the controller gain. It is shown that the scheme is tolerant of the mismatch and consequently only infrequent pseudoinverse computations are needed during a typical robot motion. As a result, the scheme is computationally fast, and can be implemented for real-time control of redundant robots. A method is incorporated to cope with the robot singularities allowing the manipulator to get very close or even pass through a singularity while maintaining a good tracking performance and acceptable joint velocities. Computer simulations and experimental results are provided in support of the theoretical developments.

  15. Low bandwidth robust controllers for flight

    NASA Technical Reports Server (NTRS)

    Biezad, Daniel J.; Chou, Hwei-Lan

    1992-01-01

    During the final reporting period (Jun. - Dec. 1992), analyses of the longitudinal and lateral flying qualities were made for propulsive-only flight control (POFC) of a Boeing 720 aircraft model. Performance resulting from compensators developed using Quantitative Feedback Theory (QFT) is documented and analyzed. This report is a first draft of a thesis to be presented by graduate student Hwei-Lan Chou. The final thesis will be presented to NASA when it is completed later this year. The latest landing metrics related to bandwidth criteria and based on the Neal-Smith approach to flying qualities prediction were used in developing performance criteria for the controllers. The compensator designs were tested on the NASA simulator and exhibited adequate performance for piloted flight. There was no significant impact of QFT on performance of the propulsive-only flight controllers in either the longitudinal or lateral modes of flight. This was attributed to the physical limits of thrust available and the engine rate of response, both of whiih severely limited the available bandwidth of the closed-loop system.

  16. Social Dancing and Incidence of Falls in Older Adults: A Cluster Randomised Controlled Trial

    PubMed Central

    Merom, Dafna; Mathieu, Erin; Cerin, Ester; Morton, Rachael L.; Simpson, Judy M.; Anstey, Kaarin J.; Sherrington, Catherine; Lord, Stephen R.; Cumming, Robert G.

    2016-01-01

    Background The prevention of falls among older people is a major public health challenge. Exercises that challenge balance are recognized as an efficacious fall prevention strategy. Given that small-scale trials have indicated that diverse dance styles can improve balance and gait of older adults, two of the strongest risk factors for falls in older people, this study aimed to determine whether social dance is effective in i) reducing the number of falls and ii) improving physical and cognitive fall-related risk factors. Methods and Findings A parallel two-arm cluster randomized controlled trial was undertaken in 23 self-care retirement villages (clusters) around Sydney, Australia. Eligible villages had to have an appropriate hall for dancing, house at least 60 residents, and not be currently offering dance as a village activity. Retirement villages were randomised using a computer generated randomisation method, constrained using minimisation. Eligible participants had to be a resident of the village, be able to walk at least 50 m, and agree to undergo physical and cognitive testing without cognitive impairment. Residents of intervention villages (12 clusters) were offered twice weekly one-hour social dancing classes (folk or ballroom dancing) over 12 mo (80 h in total). Programs were standardized across villages and were delivered by eight dance teachers. Participants in the control villages (11 clusters) were advised to continue with their regular activities. Main outcomes: falls during the 12 mo trial and Trail Making Tests. Secondary outcomes: The Physiological Performance Assessment (i.e., postural sway, proprioception, reaction time, leg strength) and the Short Physical Performance Battery; health-related physical and mental quality of life from the Short-Form 12 (SF-12) Survey. Data on falls were obtained from 522 of 530 (98%) randomised participants (mean age 78 y, 85% women) and 424 (80%) attended the 12-mo reassessment, which was lower among folk dance

  17. Home based management in multiple sclerosis: results of a randomised controlled trial

    PubMed Central

    Pozzilli, C; Brunetti, M; Amicosante, A; Gasperini, C; Ristori, G; Palmisano, L; Battaglia, M

    2002-01-01

    Background: Home based medical care is a popular alternative to standard hospital care but there is uncertainty about its cost-effectiveness. Objectives: To compare the effectiveness and the costs of multidisciplinary home based care in multiple sclerosis with hospital care in a prospective randomised controlled trial with a one year follow up. Methods: 201 patients with clinically definite multiple sclerosis were studied. They were randomised in a ratio 2:1 to an intervention group (133) or a control group (68). They were assessed at baseline and one year after randomisation with validated measures of physical and psychological impairment and quality of life (SF-36 health survey). The costs to the National Health Service over the one year follow up were calculated by a cost minimisation analysis. Results: There were no differences in functional status between the home based care group and the hospital group. There was a significant difference between the two groups favouring home based management in four SF-36 health dimensions—general health, bodily pain, role-emotional, and social functioning (all p ≤ 0.001). The cost of home based care was slightly less (822 euros/patient/year) than hospital care, mainly as a result of a reduction in hospital admissions. Conclusions: Comprehensive planning of home based intervention implemented by an interdisciplinary team and designed specifically for people with multiple sclerosis may provide a cost-effective approach to management and improve the quality of life. PMID:12185154

  18. A Computational Framework to Control Verification and Robustness Analysis

    NASA Technical Reports Server (NTRS)

    Crespo, Luis G.; Kenny, Sean P.; Giesy, Daniel P.

    2010-01-01

    This paper presents a methodology for evaluating the robustness of a controller based on its ability to satisfy the design requirements. The framework proposed is generic since it allows for high-fidelity models, arbitrary control structures and arbitrary functional dependencies between the requirements and the uncertain parameters. The cornerstone of this contribution is the ability to bound the region of the uncertain parameter space where the degradation in closed-loop performance remains acceptable. The size of this bounding set, whose geometry can be prescribed according to deterministic or probabilistic uncertainty models, is a measure of robustness. The robustness metrics proposed herein are the parametric safety margin, the reliability index, the failure probability and upper bounds to this probability. The performance observed at the control verification setting, where the assumptions and approximations used for control design may no longer hold, will fully determine the proposed control assessment.

  19. Adaptive integral robust control and application to electromechanical servo systems.

    PubMed

    Deng, Wenxiang; Yao, Jianyong

    2017-03-01

    This paper proposes a continuous adaptive integral robust control with robust integral of the sign of the error (RISE) feedback for a class of uncertain nonlinear systems, in which the RISE feedback gain is adapted online to ensure the robustness against disturbances without the prior bound knowledge of the additive disturbances. In addition, an adaptive compensation integrated with the proposed adaptive RISE feedback term is also constructed to further reduce design conservatism when the system also exists parametric uncertainties. Lyapunov analysis reveals the proposed controllers could guarantee the tracking errors are asymptotically converging to zero with continuous control efforts. To illustrate the high performance nature of the developed controllers, numerical simulations are provided. At the end, an application case of an actual electromechanical servo system driven by motor is also studied, with some specific design consideration, and comparative experimental results are obtained to verify the effectiveness of the proposed controllers.

  20. Corticosteroids in acute traumatic brain injury: systematic review of randomised controlled trials.

    PubMed Central

    Alderson, P.; Roberts, I.

    1997-01-01

    OBJECTIVE: To quantify the effectiveness and safety of corticosteroids in the treatment of acute traumatic brain injury. DESIGN: Systematic review of randomised controlled trials of corticosteroids in acute traumatic brain injury. Summary odds ratios were estimated as an inverse variance weighted average of the odds ratios for each study. SETTING: Randomised trials available by March 1996. SUBJECTS: The included trials with outcome data comprised 2073 randomised participants. RESULTS: The effect of corticosteroids on the risk of death was reported in 13 included trials. The pooled odds ratio for the 13 trials was 0.91 (95% confidence interval 0.74 to 1.12). Pooled absolute risk reduction was 1.8% (-2.5% to 5.7%). For the 10 trials that reported death or disability the pooled odds ratio was 0.90 (0.72 to 1.11). For infections of any type the pooled odds ratio was 0.92 (0.69 to 1.23) and for the seven trials reporting gastrointestinal bleeding it was 1.05 (0.44 to 2.52). With only those trials with the best quality of concealment of allocation, the pooled odds ratio estimates for death and death or disability became closer to unity. CONCLUSIONS: This systematic review of randomised controlled trials of corticosteroids in acute traumatic brain injury shows that there remains considerable uncertainty over their effects. Neither moderate benefits nor moderate harmful effects can be excluded. The widely practicable nature of the drugs and the importance of the health problem suggest that large simple trials are feasible and worth while to establish whether there are any benefits from use of corticosteroids in this setting. PMID:9224126

  1. Inositol for the prevention of neural tube defects: a pilot randomised controlled trial.

    PubMed

    Greene, Nicholas D E; Leung, Kit-Yi; Gay, Victoria; Burren, Katie; Mills, Kevin; Chitty, Lyn S; Copp, Andrew J

    2016-03-28

    Although peri-conceptional folic acid (FA) supplementation can prevent a proportion of neural tube defects (NTD), there is increasing evidence that many NTD are FA non-responsive. The vitamin-like molecule inositol may offer a novel approach to preventing FA-non-responsive NTD. Inositol prevented NTD in a genetic mouse model, and was well tolerated by women in a small study of NTD recurrence. In the present study, we report the Prevention of Neural Tube Defects by Inositol (PONTI) pilot study designed to gain further experience of inositol usage in human pregnancy as a preliminary trial to a future large-scale controlled trial to evaluate efficacy of inositol in NTD prevention. Study subjects were UK women with a previous NTD pregnancy who planned to become pregnant again. Of 117 women who made contact, ninety-nine proved eligible and forty-seven agreed to be randomised (double-blind) to peri-conceptional supplementation with inositol plus FA or placebo plus FA. In total, thirty-three randomised pregnancies produced one NTD recurrence in the placebo plus FA group (n 19) and no recurrences in the inositol plus FA group (n 14). Of fifty-two women who declined randomisation, the peri-conceptional supplementation regimen and outcomes of twenty-two further pregnancies were documented. Two NTD recurred, both in women who took only FA in their next pregnancy. No adverse pregnancy events were associated with inositol supplementation. The findings of the PONTI pilot study encourage a large-scale controlled trial of inositol for NTD prevention, but indicate the need for a careful study design in view of the unwillingness of many high-risk women to be randomised.

  2. Robust Control and Synchronization of Chaos

    DTIC Science & Technology

    2007-11-02

    parameters. In addition, we have set up a two-axis acousto - optic laser beam deflector that will be used to deliver control perturbations to the system at...a) (c) (b) ( d ) Figure 5.4: Dynamical behavior of the new source of chaotic optical frequency flucations. For low amplifier gain, the frequency of...PROGRESS REPORTS; SEE PAGE 2 FOR INTERIM PROGRESS REPORT INSTRUCTIONS. MEMORANDUM OF TRANSMITTAL U.S. Army Research Office ATTN: AMSRL-RO-BI (TR) P.O

  3. A randomised controlled trial of Silirum vaccine for control of paratuberculosis in farmed red deer.

    PubMed

    Stringer, L A; Wilson, P R; Heuer, C; Mackintosh, C G

    2013-12-07

    A randomised controlled trial to assess the efficacy of Silirum vaccine in control of paratuberculosis in young farmed deer was carried out in 2008-2009 in six New Zealand herds with a history of clinical disease. Vaccination with Silirum was carried out in four-month-old deer, and vaccinates (n=1671) and controls (n=1664) were weighed at vaccination and at 8 and 12 months old, when faecal samples were collected from 125 vaccinates and 123 controls on five farms. Deer were slaughtered between 11 and 20 months of age, and the incidence of gross visceral lymph node (VLN) pathology typical of paratuberculosis in deer, that is, enlarged and/or granulomatous VLN, was recorded. Clinical disease was confirmed in 18 controls and seven vaccinates, representing a vaccine efficacy estimate of 60 per cent (95% CI 3 per cent to 83 per cent, P=0.04). Forty-seven percent (95% CI 38 per cent to 56 per cent) of faecal samples from vaccinates and 55 per cent (95% CI 46 per cent to 64 per cent) from controls were Mycobacterium avium subspecies paratuberculosis positive (P=0.5). Average daily liveweight gain did not differ between the cohorts. At slaughter, 1.4 per cent of vaccinates and 4.5 per cent of controls had VLN pathology, RR=0.32 (95% CI 0.19 to 0.54, P<0.001). These data indicate that vaccination with Silirum may be useful as an aid to control losses associated with clinical paratuberculosis in young deer.

  4. The Diabetes Care Project: an Australian multicentre, cluster randomised controlled trial [study protocol

    PubMed Central

    2013-01-01

    Background Diabetes mellitus is an increasingly prevalent metabolic disorder that is associated with substantial disease burden. Australia has an opportunity to improve ways of caring for the growing number of people with diabetes, but this may require changes to the way care is funded, organised and delivered. To inform how best to care for people with diabetes, and to identify the extent of change that is required to achieve this, the Diabetes Care Project (DCP) will evaluate the impact of two different, evidence-based models of care (compared to usual care) on clinical quality, patient and provider experience, and cost. Methods/Design The DCP uses a pragmatic, cluster randomised controlled trial design. Accredited general practices that are situated within any of the seven Australian Medicare Locals/Divisions of General Practice that have agreed to take part in the study were invited to participate. Consenting practices will be randomly assigned to one of three treatment groups for approximately 18 to 22 months: (a) control group (usual care); (b) Intervention 1 (which tests improvements that could be made within the current funding model, facilitated through the use of an online chronic disease management network); or (c) Intervention 2 (which includes the same components as Intervention 1, as well as altered funding to support voluntary patient registration with their practice, incentive payments and a care facilitator). Adult patients who attend the enrolled practices and have established (≥12 month’s duration) type 1 diabetes mellitus or newly diagnosed or established type 2 diabetes mellitus are invited to participate. Multiple outcomes will be studied, including changes in glycosylated haemoglobin (primary outcome), changes in other biochemical and clinical metrics, incidence of diabetes-related complications, quality of life, clinical depression, success of tailored care, patient and practitioner satisfaction, and budget sustainability. Discussion

  5. Robust adaptive control of MEMS triaxial gyroscope using fuzzy compensator.

    PubMed

    Fei, Juntao; Zhou, Jian

    2012-12-01

    In this paper, a robust adaptive control strategy using a fuzzy compensator for MEMS triaxial gyroscope, which has system nonlinearities, including model uncertainties and external disturbances, is proposed. A fuzzy logic controller that could compensate for the model uncertainties and external disturbances is incorporated into the adaptive control scheme in the Lyapunov framework. The proposed adaptive fuzzy controller can guarantee the convergence and asymptotical stability of the closed-loop system. The proposed adaptive fuzzy control strategy does not depend on accurate mathematical models, which simplifies the design procedure. The innovative development of intelligent control methods incorporated with conventional control for the MEMS gyroscope is derived with the strict theoretical proof of the Lyapunov stability. Numerical simulations are investigated to verify the effectiveness of the proposed adaptive fuzzy control scheme and demonstrate the satisfactory tracking performance and robustness against model uncertainties and external disturbances compared with conventional adaptive control method.

  6. Robust time and frequency domain estimation methods in adaptive control

    NASA Technical Reports Server (NTRS)

    Lamaire, Richard Orville

    1987-01-01

    A robust identification method was developed for use in an adaptive control system. The type of estimator is called the robust estimator, since it is robust to the effects of both unmodeled dynamics and an unmeasurable disturbance. The development of the robust estimator was motivated by a need to provide guarantees in the identification part of an adaptive controller. To enable the design of a robust control system, a nominal model as well as a frequency-domain bounding function on the modeling uncertainty associated with this nominal model must be provided. Two estimation methods are presented for finding parameter estimates, and, hence, a nominal model. One of these methods is based on the well developed field of time-domain parameter estimation. In a second method of finding parameter estimates, a type of weighted least-squares fitting to a frequency-domain estimated model is used. The frequency-domain estimator is shown to perform better, in general, than the time-domain parameter estimator. In addition, a methodology for finding a frequency-domain bounding function on the disturbance is used to compute a frequency-domain bounding function on the additive modeling error due to the effects of the disturbance and the use of finite-length data. The performance of the robust estimator in both open-loop and closed-loop situations is examined through the use of simulations.

  7. Robust Multivariable Controller Design via Implicit Model-Following Methods.

    DTIC Science & Technology

    1983-12-01

    HD-Ri38 309 ROBUST MULTIVARIABLE CONTROLLER DESIGN VIA IMPLICIT 1/4 MODEL-FOLLOWING METHODS(U) AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH SCHOOL...aaS. a%. 1 .111 I Q~ 18 0 ROBUST MULTIVARIABLE CONTROLLER DESIGN -~ :VIA IMPLICIT MODEL-FOLLOWING METHODS ’.% THESIS , AFIT/GE/EE/83D-48 William G... CONTROLLER DESIGN VIA IMPLICIT MODEL-FOLLOWING METHODS THESIS AFIT/GE/EE/83D-48 William G. Miller Capt USAF ,. Approved for pubi release; distribution

  8. Robust levitation control for maglev systems with guaranteed bounded airgap.

    PubMed

    Xu, Jinquan; Chen, Ye-Hwa; Guo, Hong

    2015-11-01

    The robust control design problem for the levitation control of a nonlinear uncertain maglev system is considered. The uncertainty is (possibly) fast time-varying. The system has magnitude limitation on the airgap between the suspended chassis and the guideway in order to prevent undesirable contact. Furthermore, the (global) matching condition is not satisfied. After a three-step state transformation, a robust control scheme for the maglev vehicle is proposed, which is able to guarantee the uniform boundedness and uniform ultimate boundedness of the system, regardless of the uncertainty. The magnitude limitation of the airgap is guaranteed, regardless of the uncertainty.

  9. A self-management programme for COPD: a randomised controlled trial.

    PubMed

    Mitchell, Katy E; Johnson-Warrington, Vicki; Apps, Lindsay D; Bankart, John; Sewell, Louise; Williams, Johanna E; Rees, Karen; Jolly, Kate; Steiner, Michael; Morgan, Mike; Singh, Sally J

    2014-12-01

    Studies of programmes of self-management support for chronic obstructive pulmonary disease (COPD) have been inconclusive. The Self-Management Programme of Activity, Coping and Education (SPACE) FOR COPD is a 6-week self-management intervention for COPD, and this study aimed to evaluate the effectiveness of this intervention in primary care. A single-blind randomised controlled trial recruited people with COPD from primary care and randomised participants to receive usual care or SPACE FOR COPD. Outcome measures were performed at baseline, 6 weeks and 6 months. The primary outcome was symptom burden, measured by the self-reported Chronic Respiratory Questionnaire (CRQ-SR) dyspnoea domain. Secondary outcomes included other domains of the CRQ-SR, shuttle walking tests, disease knowledge, anxiety, depression, self-efficacy, smoking status and healthcare utilisation. 184 people with COPD were recruited and randomised. At 6 weeks, there were significant differences between groups in CRQ-SR dyspnoea, fatigue and emotion scores, exercise performance, anxiety, and disease knowledge. At 6 months, there was no between-group difference in change in CRQ-SR dyspnoea. Exercise performance, anxiety and smoking status were significantly different between groups at 6 months, in favour of the intervention. This brief self-management intervention did not improve dyspnoea over and above usual care at 6 months; however, there were gains in anxiety, exercise performance, and disease knowledge.

  10. Study protocol for a randomised controlled trial of invasive versus conservative management of primary spontaneous pneumothorax

    PubMed Central

    Brown, Simon G A; Ball, Emma L; Perrin, Kyle; Read, Catherine A; Asha, Stephen E; Beasley, Richard; Egerton-Warburton, Diana; Jones, Peter G; Keijzers, Gerben; Kinnear, Frances B; Kwan, Ben C H; Lee, Y C Gary; Smith, Julian A; Summers, Quentin A; Simpson, Graham

    2016-01-01

    Introduction Current management of primary spontaneous pneumothorax (PSP) is variable, with little evidence from randomised controlled trials to guide treatment. Guidelines emphasise intervention in many patients, which involves chest drain insertion, hospital admission and occasionally surgery. However, there is evidence that conservative management may be effective and safe, and it may also reduce the risk of recurrence. Significant questions remain regarding the optimal initial approach to the management of PSP. Methods and analysis This multicentre, prospective, randomised, open label, parallel group, non-inferiority study will randomise 342 participants with a first large PSP to conservative or interventional management. To maintain allocation concealment, randomisation will be performed in real time by computer and stratified by study site. Conservative management will involve a period of observation prior to discharge, with intervention for worsening symptoms or physiological instability. Interventional treatment will involve insertion of a small bore drain. If drainage continues after 1 hour, the patient will be admitted. If drainage stops, the drain will be clamped for 4 hours. The patient will be discharged if the lung remains inflated. Otherwise, the patient will be admitted. The primary end point is the proportion of participants with complete lung re-expansion by 8 weeks. Secondary end points are as follows: days in hospital, persistent air leak, predefined complications and adverse events, time to resolution of symptoms, and pneumothorax recurrence during a follow-up period of at least 1 year. The study has 95% power to detect an absolute non-inferiority margin of 9%, assuming 99% successful expansion at 8 weeks in the invasive treatment arm. The primary analysis will be by intention to treat. Ethics and dissemination Local ethics approval has been obtained for all sites. Study findings will be disseminated by publication in a high

  11. A randomised controlled trial. Shifting boundaries of doctors and physiotherapists in orthopaedic outpatient departments

    PubMed Central

    Daker-White, G.; Carr, A. J.; Harvey, I.; Woolhead, G.; Bannister, G.; Nelson, I.; Kammerling, M.

    1999-01-01

    OBJECTIVE: To evaluate the effectiveness and cost effectiveness of specially trained physiotherapists in the assessment and management of defined referrals to hospital orthopaedic departments. DESIGN: Randomised controlled trial. SETTING: Orthopaedic outpatient departments in two hospitals. SUBJECTS: 481 patients with musculoskeletal problems referred for specialist orthopaedic opinion. INTERVENTIONS: Initial assessment and management undertaken by post- Fellowship junior orthopaedic surgeons, or by specially trained physiotherapists working in an extended role (orthopaedic physiotherapy specialists). MAIN OUTCOME MEASURES: Patient centred measures of pain, functional disability and perceived handicap. RESULTS: A total of 654 patients were eligible to join the trial, 481 (73.6%) gave their consent to be randomised. The two arms (doctor n = 244, physiotherapist n = 237) were similar at baseline. Baseline and follow up questionnaires were completed by 383 patients (79.6%). The mean time to follow up was 5.6 months after randomisation, with similar distributions of intervals to follow up in both arms. The only outcome for which there was a statistically or clinically important difference between arms was in a measure of patient satisfaction, which favoured the physiotherapist arm. A cost minimisation analysis showed no significant differences in direct costs to the patient or NHS primary care costs. Direct hospital costs were lower (p < 0.00001) in the physiotherapist arm (mean cost per patient = 256 Pounds, n = 232), as they were less likely to order radiographs and to refer patients for orthopaedic surgery than were the junior doctors (mean cost per patient in arm = 498 Pounds, n = 238). CONCLUSIONS: On the basis of the patient centred outcomes measured in this randomised trial, orthopaedic physiotherapy specialists are as effective as post-Fellowship junior staff and clinical assistant orthopaedic surgeons in the initial assessment and management of new referrals

  12. Robust decentralized controller design for UPFC using μ-synthesis

    NASA Astrophysics Data System (ADS)

    Taher, Seyed Abbas; Akbari, Shahabeddin; Abdolalipour, Ali; Hematti, Reza

    2010-08-01

    In this paper a new method based on structured singular value ( μ-synthesis) is proposed for the robust decentralized unified power flow controller (UPFC) design. To achieve decentralization, using the Schauder fixed point theorem the synthesis and analysis of multi-input multi-output (MIMO) control system is transformed into a set of equivalent multi-input single-output (MISO) control system. To cope with power system uncertainties μ-synthesis technique is being used for designing of UPFC controllers. The proposed μ-based controller has a decentralized scheme which has the advantage of reduction in the controller complexity and suitability for practical implementation. The effectiveness of the proposed control strategy on damping low frequency oscillations is evaluated under different operating conditions and compared with the conventional controller to demonstrate its robust performance through nonlinear simulation and some performance indices.

  13. Robust Control Design for Uncertain Nonlinear Dynamic Systems

    NASA Technical Reports Server (NTRS)

    Kenny, Sean P.; Crespo, Luis G.; Andrews, Lindsey; Giesy, Daniel P.

    2012-01-01

    Robustness to parametric uncertainty is fundamental to successful control system design and as such it has been at the core of many design methods developed over the decades. Despite its prominence, most of the work on robust control design has focused on linear models and uncertainties that are non-probabilistic in nature. Recently, researchers have acknowledged this disparity and have been developing theory to address a broader class of uncertainties. This paper presents an experimental application of robust control design for a hybrid class of probabilistic and non-probabilistic parametric uncertainties. The experimental apparatus is based upon the classic inverted pendulum on a cart. The physical uncertainty is realized by a known additional lumped mass at an unknown location on the pendulum. This unknown location has the effect of substantially altering the nominal frequency and controllability of the nonlinear system, and in the limit has the capability to make the system neutrally stable and uncontrollable. Another uncertainty to be considered is a direct current motor parameter. The control design objective is to design a controller that satisfies stability, tracking error, control power, and transient behavior requirements for the largest range of parametric uncertainties. This paper presents an overview of the theory behind the robust control design methodology and the experimental results.

  14. Robustness with observers. [linear optimal feedback control systems

    NASA Technical Reports Server (NTRS)

    Doyle, J. C.; Stein, G.

    1979-01-01

    The paper describes an adjustment procedure for observer-based linear control systems which asymptotically achieves the same loop transfer functions (and hence the same relative stability, robustness, and disturbance rejection properties) as full-state feedback control implementations. Full-state loop-transfer properties can be recovered asymptotically if the plant is minimum phase; this occurs at the expense of noise performance.

  15. A decentralized adaptive robust method for chaos control.

    PubMed

    Kobravi, Hamid-Reza; Erfanian, Abbas

    2009-09-01

    This paper presents a control strategy, which is based on sliding mode control, adaptive control, and fuzzy logic system for controlling the chaotic dynamics. We consider this control paradigm in chaotic systems where the equations of motion are not known. The proposed control strategy is robust against the external noise disturbance and system parameter variations and can be used to convert the chaotic orbits not only to the desired periodic ones but also to any desired chaotic motions. Simulation results of controlling some typical higher order chaotic systems demonstrate the effectiveness of the proposed control method.

  16. Optimal robust motion controller design using multiobjective genetic algorithm.

    PubMed

    Sarjaš, Andrej; Svečko, Rajko; Chowdhury, Amor

    2014-01-01

    This paper describes the use of a multiobjective genetic algorithm for robust motion controller design. Motion controller structure is based on a disturbance observer in an RIC framework. The RIC approach is presented in the form with internal and external feedback loops, in which an internal disturbance rejection controller and an external performance controller must be synthesised. This paper involves novel objectives for robustness and performance assessments for such an approach. Objective functions for the robustness property of RIC are based on simple even polynomials with nonnegativity conditions. Regional pole placement method is presented with the aims of controllers' structures simplification and their additional arbitrary selection. Regional pole placement involves arbitrary selection of central polynomials for both loops, with additional admissible region of the optimized pole location. Polynomial deviation between selected and optimized polynomials is measured with derived performance objective functions. A multiobjective function is composed of different unrelated criteria such as robust stability, controllers' stability, and time-performance indexes of closed loops. The design of controllers and multiobjective optimization procedure involve a set of the objectives, which are optimized simultaneously with a genetic algorithm-differential evolution.

  17. Optimal Robust Motion Controller Design Using Multiobjective Genetic Algorithm

    PubMed Central

    Svečko, Rajko

    2014-01-01

    This paper describes the use of a multiobjective genetic algorithm for robust motion controller design. Motion controller structure is based on a disturbance observer in an RIC framework. The RIC approach is presented in the form with internal and external feedback loops, in which an internal disturbance rejection controller and an external performance controller must be synthesised. This paper involves novel objectives for robustness and performance assessments for such an approach. Objective functions for the robustness property of RIC are based on simple even polynomials with nonnegativity conditions. Regional pole placement method is presented with the aims of controllers' structures simplification and their additional arbitrary selection. Regional pole placement involves arbitrary selection of central polynomials for both loops, with additional admissible region of the optimized pole location. Polynomial deviation between selected and optimized polynomials is measured with derived performance objective functions. A multiobjective function is composed of different unrelated criteria such as robust stability, controllers' stability, and time-performance indexes of closed loops. The design of controllers and multiobjective optimization procedure involve a set of the objectives, which are optimized simultaneously with a genetic algorithm—differential evolution. PMID:24987749

  18. Effectiveness of financial incentives to improve adherence to maintenance treatment with antipsychotics: cluster randomised controlled trial

    PubMed Central

    Yeeles, Ksenija; Bremner, Stephen; Lauber, Christoph; Eldridge, Sandra; Ashby, Deborah; David, Anthony S; O’Connell, Nicola; Forrest, Alexandra; Burns, Tom

    2013-01-01

    Objective To test whether offering financial incentives to patients with psychotic disorders is effective in improving adherence to maintenance treatment with antipsychotics. Design Cluster randomised controlled trial. Setting Community mental health teams in secondary psychiatric care in the United Kingdom. Participants Patients with a diagnosis of schizophrenia, schizoaffective disorder, or bipolar disorder, who were prescribed long acting antipsychotic (depot) injections but had received 75% or less of the prescribed injections. We randomly allocated 73 teams with a total of 141 patients. Primary outcome data were available for 35 intervention teams with 75 patients (96% of randomised) and for 31 control teams with 56 patients (89% of randomised). Interventions Participants in the intervention group were offered £15 (€17; $22) for each depot injection over a 12 month period. Participants in the control condition received treatment as usual. Main outcome measure The primary outcome was the percentage of prescribed depot injections given during the 12 month intervention period. Results 73 teams with 141 consenting patients were randomised, and outcomes were assessed for 131 patients (93%). Average baseline adherence was 69% in the intervention group and 67% in the control group. During the 12 month trial period adherence was 85% in the intervention group and 71% in the control group. The adjusted effect estimate was 11.5% (95% confidence interval 3.9% to 19.0%, P=0.003). A secondary outcome was an adherence of ≥95%, which was achieved in 28% of the intervention group and 5% of the control group (adjusted odds ratio 8.21, 95% confidence interval 2.00 to 33.67, P=0.003). Although differences in clinician rated clinical improvement between the groups failed to reach statistical significance, patients in the intervention group had more favourable subjective quality of life ratings (β=0.71, 95% confidence interval 0.26 to 1.15, P=0.002). The number of admissions

  19. Sahaja yoga in the management of moderate to severe asthma: a randomised controlled trial

    PubMed Central

    Manocha, R; Marks, G; Kenchington, P; Peters, D; Salome, C

    2002-01-01

    Background: Sahaja Yoga is a traditional system of meditation based on yogic principles which may be used for therapeutic purposes. A study was undertaken to assess the effectiveness of this therapy as an adjunctive tool in the management of asthma in adult patients who remained symptomatic on moderate to high doses of inhaled steroids. Methods: A parallel group, double blind, randomised controlled trial was conducted. Subjects were randomly allocated to Sahaja yoga and control intervention groups. Both the yoga and the control interventions required the subjects to attend a 2 hour session once a week for 4 months. Asthma related quality of life (AQLQ, range 0–4), Profile of Mood States (POMS), level of airway hyperresponsiveness to methacholine (AHR), and a diary card based combined asthma score (CAS, range 0–12) reflecting symptoms, bronchodilator usage, and peak expiratory flow rates were measured at the end of the treatment period and again 2 months later. Results: Twenty one of 30 subjects randomised to the yoga intervention and 26 of 29 subjects randomised to the control group were available for assessment at the end of treatment. The improvement in AHR at the end of treatment was 1.5 doubling doses (95% confidence interval (CI) 0.0 to 2.9, p=0.047) greater in the yoga intervention group than in the control group. Differences in AQLQ score (0.41, 95% CI –0.04 to 0.86) and CAS (0.9, 95% CI –0.9 to 2.7) were not significant (p>0.05). The AQLQ mood subscale did improve more in the yoga group than in the control group (difference 0.63, 95% CI 0.06 to 1.20), as did the summary POMS score (difference 18.4, 95% CI 0.2 to 36.5, p=0.05). There were no significant differences between the two groups at the 2 month follow up assessment. Conclusions: This randomised controlled trial has shown that the practice of Sahaja yoga does have limited beneficial effects on some objective and subjective measures of the impact of asthma. Further work is required to

  20. Farm practices to control E. coli O157 in young cattle--a randomised controlled trial.

    PubMed

    Ellis-Iversen, Johanne; Smith, Richard P; Van Winden, Steven; Paiba, Giles A; Watson, Eamon; Snow, Lucy C; Cook, Alasdair J C

    2008-01-01

    A randomised controlled trial was used to investigate the effect of three complex management intervention packages to reduce the burden of E. coli O157 in groups of young-stock on cattle farms in England and Wales. All intervention farms were assigned measures to avoid buying in new animals and having direct contact or sharing water sources with other cattle. Furthermore, package A (7 farms) aimed to keep a clean environment and closed groups of young-stock; package B (14 farms) aimed for improved water and feed hygiene, whilst package C was assigned both A and B. The control farms (26 farms) were asked not to alter their practices. Farms, which were assigned intervention package A, exhibited a 48% reduction in E. coli O157 burden over the 4.5 months (average) of observation, compared to 18% on the control farms. The effect of package A compared to the control farms in a crude intention-to-treat model was RR = 0.26 (p=0.122). When the risk ratio was adjusted for actual application of the different measures, the effect of intervention package A became stronger and statistically significant (RR = 0.14 p=0.032). Statistical evidence (p< 0.05) showed that dry bedding and maintaining animals in the same groups were the most important measures within the package and weak evidence (p< 0.1) showed that a closed herd policy and no contact with other cattle may also be of importance. Compliance with the other measures in package A had no influence on the effect of the package. No evidence of effect of the other two intervention packages was found.

  1. Robust hopping based on virtual pendulum posture control.

    PubMed

    Sharbafi, Maziar A; Maufroy, Christophe; Ahmadabadi, Majid Nili; Yazdanpanah, Mohammad J; Seyfarth, Andre

    2013-09-01

    A new control approach to achieve robust hopping against perturbations in the sagittal plane is presented in this paper. In perturbed hopping, vertical body alignment has a significant role for stability. Our approach is based on the virtual pendulum concept, recently proposed, based on experimental findings in human and animal locomotion. In this concept, the ground reaction forces are pointed to a virtual support point, named virtual pivot point (VPP), during motion. This concept is employed in designing the controller to balance the trunk during the stance phase. New strategies for leg angle and length adjustment besides the virtual pendulum posture control are proposed as a unified controller. This method is investigated by applying it on an extension of the spring loaded inverted pendulum (SLIP) model. Trunk, leg mass and damping are added to the SLIP model in order to make the model more realistic. The stability is analyzed by Poincaré map analysis. With fixed VPP position, stability, disturbance rejection and moderate robustness are achieved, but with a low convergence speed. To improve the performance and attain higher robustness, an event-based control of the VPP position is introduced, using feedback of the system states at apexes. Discrete linear quartic regulator is used to design the feedback controller. Considerable enhancements with respect to stability, convergence speed and robustness against perturbations and parameter changes are achieved.

  2. Robust and reliable control via quadratic Lyapunov functions

    NASA Astrophysics Data System (ADS)

    Alt, Terry Robert

    In this dissertation we present a new approach to design robust and reliable controllers. Our results are used to find control laws for systems that are subject to (1) real polytopic and norm bounded uncertainties, (2) actuator and sensor variations and (3) actuator and sensor failure. In addition, we present conditions that can be added to the control design problem to constrain the controller to be stable or strictly positive real, further strengthening the robustness and reliability of the control design. The basic framework relies on the use of quadratic Lyapunov functions to accommodate potentially time varying uncertainty. Conditions are derived that, when satisfied, allow a robust control design to be obtained by performing two convex optimizations. These controllers recover the performance robustness of either state feedback or full information controllers. Sufficient conditions are presented that remove the non-convexity in terms of the control design variables. This allows a robust control design to be obtained by solving a set of linear matrix inequalities. These general robustness results are then applied to the reliability problem. Actuator and sensor variations are modeled using real polytopic uncertainties. It is shown that under some simplifying assumptions the state feedback problem reduces to a single linear matrix inequality. It also shows that the Riccati equations for standard LQR and Hsb{infty} need only a slight modification to obtain a control law that is reliable with respect to actuator variability. For the output feedback case, convex conditions are presented that yield controllers which are reliable to actuator and sensor variations. Utilizing the simultaneous Lyapunov function approach, we further extend these results to include actuator or sensor failure. Additionally, when applicable, stronger reliability guaranties may be obtained by constraining the controller to be strictly positive real. This guarantees stability for positive real

  3. Analysis the robustness of control systems based on disturbance observer

    NASA Astrophysics Data System (ADS)

    Sariyildiz, Emre; Ohnishi, Kouhei

    2013-10-01

    Disturbance observer (DOB) estimates the system disturbances by using the inverse of the nominal plant model and a low pass filter (LPF). Although the LPF provides the properness in the inner-loop, it is the main design constraint of the control systems based on DOB. The bandwidth of the LPF is designed as high as possible so that the DOB can estimate the disturbances in a wider frequency range. However, its bandwidth is limited by noise and robustness of the system. The robustness limitation is directly related with the robustness analysis methods, and they significantly affect the performance of the DOB based control systems. In this paper, three different robustness analysis methods are implemented into the DOB based control systems, and the relation between the robustness of the system and bandwidth of DOB is clearly explained. The conservatism, which is the main drawback of the conventional analysis methods, on the bandwidth of DOB is removed by proposing a new real parametric uncertainty based analysis method. The proposed methods are compared in detail, and simulation results are given to show the validation.

  4. Ultrasound in management of rheumatoid arthritis: ARCTIC randomised controlled strategy trial

    PubMed Central

    Aga, Anna-Birgitte; Olsen, Inge Christoffer; Lillegraven, Siri; Hammer, Hilde B; Uhlig, Till; Fremstad, Hallvard; Madland, Tor Magne; Lexberg, Åse Stavland; Haukeland, Hilde; Rødevand, Erik; Høili, Christian; Stray, Hilde; Noraas, Anne; Hansen, Inger Johanne Widding; Bakland, Gunnstein; Nordberg, Lena Bugge; van der Heijde, Désirée; Kvien, Tore K

    2016-01-01

    Objective To determine whether a treatment strategy based on structured ultrasound assessment would lead to improved outcomes in rheumatoid arthritis, compared with a conventional strategy. Design Multicentre, open label, two arm, parallel group, randomised controlled strategy trial. Setting Ten rheumatology departments and one specialist centre in Norway, from September 2010 to September 2015. Participants 238 patients were recruited between September 2010 and April 2013, of which 230 (141 (61%) female) received the allocated intervention and were analysed for the primary outcome. The main inclusion criteria were age 18-75 years, fulfilment of the 2010 American College of Rheumatology/European League Against Rheumatism classification criteria for rheumatoid arthritis, disease modifying anti-rheumatic drug naivety with indication for disease modifying drug therapy, and time from first patient reported swollen joint less than two years. Patients with abnormal kidney or liver function or major comorbidities were excluded. Interventions 122 patients were randomised to an ultrasound tight control strategy targeting clinical and imaging remission, and 116 patients were randomised to a conventional tight control strategy targeting clinical remission. Patients in both arms were treated according to the same disease modifying anti-rheumatic drug escalation strategy, with 13 visits over two years. Main outcome measures The primary endpoint was the proportion of patients with a combination between 16 and 24 months of clinical remission, no swollen joints, and non-progression of radiographic joint damage. Secondary outcomes included measures of disease activity, radiographic progression, functioning, quality of life, and adverse events. All participants who attended at least one follow-up visit were included in the full analysis set. Results 26 (22%) of the 118 analysed patients in the ultrasound tight control arm and 21 (19%) of the 112 analysed patients in the

  5. Study protocol for a randomised controlled trial of electronic cigarettes versus nicotine patch for smoking cessation

    PubMed Central

    2013-01-01

    Background Electronic cigarettes (e-cigarettes or electronic nicotine delivery systems [ENDS]) are electrically powered devices generally similar in appearance to a cigarette that deliver a propylene glycol and/or glycerol mist to the airway of users when drawing on the mouthpiece. Nicotine and other substances such as flavourings may be included in the fluid vaporised by the device. People report using e-cigarettes to help quit smoking and studies of their effects on tobacco withdrawal and craving suggest good potential as smoking cessation aids. However, to date there have been no adequately powered randomised trials investigating their cessation efficacy or safety. This paper outlines the protocol for this study. Methods/design Design: Parallel group, 3-arm, randomised controlled trial. Participants: People aged ≥18 years resident in Auckland, New Zealand (NZ) who want to quit smoking. Intervention: Stratified blocked randomisation to allocate participants to either Elusion™ e-cigarettes with nicotine cartridges (16 mg) or with placebo cartridges (i.e. no nicotine), or to nicotine patch (21 mg) alone. Participants randomised to the e-cigarette groups will be told to use them ad libitum for one week before and 12 weeks after quit day, while participants randomised to patches will be told to use them daily for the same period. All participants will be offered behavioural support to quit from the NZ Quitline. Primary outcome: Biochemically verified (exhaled carbon monoxide) continuous abstinence at six months after quit day. Sample size: 657 people (292 in both the nicotine e-cigarette and nicotine patch groups and 73 in the placebo e-cigarettes group) will provide 80% power at p = 0.05 to detect an absolute difference of 10% in abstinence between the nicotine e-cigarette and nicotine patch groups, and 15% between the nicotine and placebo e-cigarette groups. Discussion This trial will inform international debate and policy on the regulation and

  6. Management of type 2 diabetes in China: the Happy Life Club, a pragmatic cluster randomised controlled trial using health coaches

    PubMed Central

    Browning, Colette; Chapman, Anna; Yang, Hui; Liu, Shuo; Zhang, Tuohong; Enticott, Joanne C; Thomas, Shane A

    2016-01-01

    Objective To assess the effectiveness of a coach-led motivational interviewing (MI) intervention in improving glycaemic control, as well as clinical, psychosocial and self-care outcomes of individuals with type 2 diabetes mellitus (T2DM) compared with usual care. Design Pragmatic cluster randomised controlled trial (RCT). Setting Community Health Stations (CHSs) in Fengtai district, Beijing, China. Participants Of the 41 randomised CHSs (21 intervention and 20 control), 21 intervention CHSs (372 participants) and 18 control CHSs (296 participants) started participation. Intervention Intervention participants received telephone and face-to-face MI health coaching in addition to usual care from their CHS. Control participants received usual care only. Medical fees were waived for both groups. Outcome measures Outcomes were assessed at baseline, 6 and 12 months. Primary outcome measure was glycated haemoglobin (HbA1c). Secondary outcomes included a suite of anthropometric, blood pressure (BP), fasting blood, psychosocial and self-care measures. Results At 12 months, no differential treatment effect was found for HbA1c (adjusted difference 0.02, 95% CI −0.40 to 0.44, p=0.929), with both treatment and control groups showing significant improvements. However, two secondary outcomes: psychological distress (adjusted difference −2.38, 95% CI −4.64 to −0.12, p=0.039) and systolic BP (adjusted difference −3.57, 95% CI −6.08 to −1.05, p=0.005) were robust outcomes consistent with significant differential treatment effects, as supported in sensitivity analyses. Interestingly, in addition to HbA1c, both groups displayed significant improvements in triglycerides, LDL cholesterol and HDL cholesterol. Conclusions In line with the current Chinese primary healthcare reform, this study is the first large-scale cluster RCT to be implemented within real-world CHSs in China, specifically addressing T2DM. Although a differential treatment effect was not observed for Hb

  7. Greening vacant lots to reduce violent crime: a randomised controlled trial

    PubMed Central

    Garvin, Eugenia C; Cannuscio, Carolyn C; Branas, Charles C

    2014-01-01

    Background Vacant lots are often overgrown with unwanted vegetation and filled with trash, making them attractive places to hide illegal guns, conduct illegal activities such as drug sales and prostitution, and engage in violent crime. There is some evidence that greening vacant lots is associated with reductions in violent crime. Methods We performed a randomised controlled trial of vacant lot greening to test the impact of this intervention on police reported crime and residents’ perceptions of safety and disorder. Greening consisted of cleaning the lots, planting grass and trees, and building a wooden fence around the perimeter. We randomly allocated two vacant lot clusters to the greening intervention or to the control status (no intervention). Administrative data were used to determine crime rates, and local resident interviews at baseline (n=29) and at follow-up (n=21) were used to assess perceptions of safety and disorder. Results Unadjusted difference-in-differences estimates showed a non-significant decrease in the number of total crimes and gun assaults around greened vacant lots compared with control. People around the intervention vacant lots reported feeling significantly safer after greening compared with those living around control vacant lots (p<0.01). Conclusions In this study, greening was associated with reductions in certain gun crimes and improvements in residents’ perceptions of safety. A larger randomised controlled trial is needed to further investigate the link between vacant lot greening and violence reduction. PMID:22871378

  8. Robust Optimal Adaptive Control Method with Large Adaptive Gain

    NASA Technical Reports Server (NTRS)

    Nguyen, Nhan T.

    2009-01-01

    In the presence of large uncertainties, a control system needs to be able to adapt rapidly to regain performance. Fast adaptation is referred to the implementation of adaptive control with a large adaptive gain to reduce the tracking error rapidly. However, a large adaptive gain can lead to high-frequency oscillations which can adversely affect robustness of an adaptive control law. A new adaptive control modification is presented that can achieve robust adaptation with a large adaptive gain without incurring high-frequency oscillations as with the standard model-reference adaptive control. The modification is based on the minimization of the Y2 norm of the tracking error, which is formulated as an optimal control problem. The optimality condition is used to derive the modification using the gradient method. The optimal control modification results in a stable adaptation and allows a large adaptive gain to be used for better tracking while providing sufficient stability robustness. Simulations were conducted for a damaged generic transport aircraft with both standard adaptive control and the adaptive optimal control modification technique. The results demonstrate the effectiveness of the proposed modification in tracking a reference model while maintaining a sufficient time delay margin.

  9. Robust control systems design by H-infinity optimization theory

    NASA Technical Reports Server (NTRS)

    Chang, B. C.; Li, X. P.; Banda, S. S.; Yeh, H. H.

    1991-01-01

    In this paper, step-by-step procedures of applying the H-infinity theory to robust control systems design are given. The objective of the paper is to eliminate the possible difficulties a control engineer may encounter in applying H-infinity control theory and to clear up some misconceptions about H-infinity theory like high-gain controller and numerical obstacles, etc. An efficient algorithm is used to compute the optimal H-infinity norm. The Glover and Doyle (1988) controller formulas are slightly modified and used to construct an optimal controller without any numerical difficulties.

  10. A new robust control for minirotorcraft unmanned aerial vehicles.

    PubMed

    Mokhtari, M Rida; Cherki, Brahim

    2015-05-01

    This paper presents a new robust control based on finite-time Lyapunov stability controller and proved with backstepping method for the position and the attitude of a small rotorcraft unmanned aerial vehicle subjected to bounded uncertainties and disturbances. The dynamical motion equations are obtained by the Newton-Euler formalism. The proposed controller combines the advantage of the backstepping approach with finite-time convergence techniques to generate a control laws to guarantee the faster convergence of the state variables to their desired values in short time and compensate for the bounded disturbances. A formal proof of the closed-loop stability and finite-time convergence of tracking errors is derived using the Lyapunov function technique. Simulation results are presented to corroborate the effectiveness and the robustness of the proposed control method.

  11. A robust composite nonlinear control scheme for servomotor speed regulation

    NASA Astrophysics Data System (ADS)

    Huang, Yanwei; Cheng, Guoqing

    2015-01-01

    A parameterised design of robust composite nonlinear controller is proposed for typical second-order servo systems subject to unknown constant disturbance and control input saturation. The control law consists of a linear feedback part for achieving fast response, a nonlinear feedback part for suppressing the overshoot, and a disturbance-compensation mechanism for erasing the steady-state error. An extended state observer is adopted to estimate the unknown disturbance. The closed-loop stability is analysed theoretically. The control scheme is applied to the speed regulation of permanent magnet synchronous motor, and numerical simulations are carried out. The results confirm that the proposed control scheme can achieve fast, smooth, and accurate speed regulation, and has a certain degree of robustness with respect to the amplitude of disturbances and the perturbations of system parameters.

  12. Wordless intervention for people with epilepsy and learning disabilities (WIELD): a randomised controlled feasibility trial

    PubMed Central

    Mengoni, Silvana E; Gates, Bob; Parkes, Georgina; Wellsted, David; Barton, Garry; Ring, Howard; Khoo, Mary Ellen; Monji-Patel, Deela; Friedli, Karin; Zia, Asif; Irvine, Lisa; Durand, Marie-Anne

    2016-01-01

    Objective To investigate the feasibility of a full-scale randomised controlled trial of a picture booklet to improve quality of life for people with epilepsy and learning disabilities. Trial design A randomised controlled feasibility trial. Randomisation was not blinded and was conducted using a centralised secure database and a blocked 1:1 allocation ratio. Setting Epilepsy clinics in 1 English National Health Service (NHS) Trust. Participants Patients with learning disabilities and epilepsy who had: a seizure within the past 12 months, meaningful communication and a carer with sufficient proficiency in English. Intervention Participants in the intervention group used a picture booklet with a trained researcher, and a carer present. These participants kept the booklet, and were asked to use it at least twice more over 20 weeks. The control group received treatment as usual, and were provided with a booklet at the end of the study. Outcome measures 7 feasibility criteria were used relating to recruitment, data collection, attrition, potential effect on epilepsy-related quality of life (Epilepsy and Learning Disabilities Quality of Life Scale, ELDQOL) at 4-week, 12-week and 20-week follow-ups, feasibility of methodology, acceptability of the intervention and potential to calculate cost-effectiveness. Outcome The recruitment rate of eligible patients was 34% and the target of 40 participants was reached. There was minimal missing data and attrition. An intention-to-treat analysis was performed; data from the outcome measures suggest a benefit from the intervention on the ELDQOL behaviour and mood subscales at 4 and 20 weeks follow-up. The booklet and study methods were positively received, and no adverse events were reported. There was a positive indication of the potential for a cost-effectiveness analysis. Conclusions All feasibility criteria were fully or partially met, therefore confirming feasibility of a definitive trial. Trial registration number ISRCTN

  13. ‘Putting Life in Years’ (PLINY) telephone friendship groups research study: pilot randomised controlled trial

    PubMed Central

    2014-01-01

    Background Loneliness in older people is associated with poor health-related quality of life (HRQoL). We undertook a parallel-group randomised controlled trial to evaluate the effectiveness and cost-effectiveness of telephone befriending for the maintenance of HRQoL in older people. An internal pilot tested the feasibility of the trial and intervention. Methods Participants aged >74 years, with good cognitive function, living independently in one UK city were recruited through general practices and other sources, then randomised to: (1) 6 weeks of short one-to-one telephone calls, followed by 12 weeks of group telephone calls with up to six participants, led by a trained volunteer facilitator; or (2) a control group. The main trial required the recruitment of 248 participants in a 1-year accrual window, of whom 124 were to receive telephone befriending. The pilot specified three success criteria which had to be met in order to progress the main trial to completion: recruitment of 68 participants in 95 days; retention of 80% participants at 6 months; successful delivery of telephone befriending by local franchise of national charity. The primary clinical outcome was the Short Form (36) Health Instrument (SF-36) Mental Health (MH) dimension score collected by telephone 6 months following randomisation. Results We informed 9,579 older people about the study. Seventy consenting participants were randomised to the pilot in 95 days, with 56 (80%) providing valid primary outcome data (26 intervention, 30 control). Twenty-four participants randomly allocated to the research arm actually received telephone befriending due to poor recruitment and retention of volunteer facilitators. The trial was closed early as a result. The mean 6-month SF-36 MH scores were 78 (SD 18) and 71 (SD 21) for the intervention and control groups, respectively (mean difference, 7; 95% CI, -3 to 16). Conclusions Recruitment and retention of participants to a definitive trial with a

  14. A prospective randomised controlled trial of capnography vs. bronchoscopy for Blue Rhino percutaneous tracheostomy.

    PubMed

    Mallick, A; Venkatanath, D; Elliot, S C; Hollins, T; Nanda Kumar, C G

    2003-09-01

    A crucial step for successful percutaneous tracheostomy is the introduction of the needle and guide wire into the trachea. Capnography has recently been proposed as one way to confirm tracheal needle placement. In this randomised controlled study, we used capnography in 26 patients and bronchoscopy in 29 patients to confirm needle placement for percutaneous tracheostomy using Blue Rhino kit. The operating times and the incidence of peri-operative complications were similar for both groups. Capnography proved to be as effective as bronchoscopy in confirming correct needle placement.

  15. A randomised controlled trial of benefit finding in caregivers: The Building Resources in Caregivers Study Protocol.

    PubMed

    Brand, Charles; O'Connell, Brenda H; Gallagher, Stephen

    2015-07-01

    Caregivers may engage in benefit finding, that is, an increase in perceived positive growth, as a cognitive strategy for coping with stress. The Building Resources in Caregivers study will compare effects of a brief benefit finding writing intervention with a control intervention. Caregivers of people with mental and physical disabilities will be randomised into either a benefit-writing group or a neutral writing group. Caregivers will complete measures relating to themselves and care-recipients (e.g. sociodemographics and illness type) and psychometric measures of benefit finding, distress and quality of life at three time points. Additionally, qualitative commentary on participation experiences will be gathered.

  16. Robust Neural Sliding Mode Control of Robot Manipulators

    NASA Astrophysics Data System (ADS)

    Hiep, Nguyen Tran; cat, Pham Thuong

    2009-03-01

    This paper proposes a robust neural sliding mode control method for robot tracking problem to overcome the noises and large uncertainties in robot dynamics. The Lyapunov direct method has been used to prove the stability of the overall system. Simulation results are given to illustrate the applicability of the proposed method

  17. Robust Neural Sliding Mode Control of Robot Manipulators

    SciTech Connect

    Nguyen Tran Hiep; Pham Thuong Cat

    2009-03-05

    This paper proposes a robust neural sliding mode control method for robot tracking problem to overcome the noises and large uncertainties in robot dynamics. The Lyapunov direct method has been used to prove the stability of the overall system. Simulation results are given to illustrate the applicability of the proposed method.

  18. Single dose vitamin A treatment in acute shigellosis in Bangladesh children: randomised double blind controlled trial.

    PubMed Central

    Hossain, S.; Biswas, R.; Kabir, I.; Sarker, S.; Dibley, M.; Fuchs, G.; Mahalanabis, D.

    1998-01-01

    OBJECTIVE: To evaluate the efficacy of a single large oral dose of vitamin A in treating acute shigellosis in children in Bangladesh. DESIGN: Randomised double blind controlled clinical trial. SETTING: Dhaka Hospital, International Centre for Diarrhoeal Disease Research, Bangladesh. SUBJECTS: 83 children aged 1-7 years with bacteriologically proved shigellosis but no clinical signs of vitamin A deficiency; 42 were randomised to treatment with vitamin A and 41 formed a control group. INTERVENTION: Children were given a single oral dose of 200,000 IU of vitamin A plus 25 IU vitamin E or a control preparation of 25 IU vitamin E. MAIN OUTCOME MEASURES: Clinical cure on study day 5 and bacteriological cure. RESULTS: Baseline characteristics of the subjects in the two treatment groups were similar. Significantly more children in the vitamin A group than in the control group achieved clinical cure (19/42 (45%) v 8/14 (20%); chi 2 = 5.14, 1 df, P = 0.02; risk ratio = 0.68 (95% confidence interval; 0.50 to 0.93)). When cure was determined bacteriologically, the groups had similar rates (16/42 (38%) v 16/41 (39%); chi 2 = 0.02, 1 df, P = 0.89; risk ratio = 0.98 (0.70 to 1.39)). CONCLUSIONS: Vitamin A reduces the severity of acute shigellosis in children living in areas where vitamin A deficiency is a major public health problem. PMID:9492664

  19. Robust model-based controller synthesis for the SCOLE configuration

    NASA Technical Reports Server (NTRS)

    Armstrong, E. S.; Joshi, S. M.; Stewart, E. J.

    1988-01-01

    The design of a robust compensator is considered for the SCOLE configuration using a frequency-response shaping technique based on the LQG/LTR algorithm. Results indicate that a tenth-order compensator can be used to meet stability-performance-robustness conditions for a 26th-order SCOLE model without destabilizing spillover effects. Since the SCOLE configuration is representative of many proposed spaceflight experiments, the results and design techniques employed potentially should be applicable to a wide range of large space structure control problems.

  20. Geometric quantum gates that are robust against stochastic control errors

    SciTech Connect

    Zhu Shiliang; Zanardi, Paolo

    2005-08-15

    The realistic application of geometric quantum computation is crucially dependent on an unproved robustness conjecture, claiming that geometric quantum gates are more resilient against random noise than dynamic gates. We propose a suitable model that allows a direct and fair comparison between geometrical and dynamical operations. In the presence of stochastic control errors we find that the maximum of gate fidelity corresponds to quantum gates with a vanishing dynamical phase. This is a clear evidence for the robustness of nonadiabatic geometric quantum computation. The predictions here presented can be experimentally tested in almost all of the already existing quantum computer candidates.

  1. Results of a feasibility randomised controlled study of the guidelines for exercise in multiple sclerosis project.

    PubMed

    Learmonth, Yvonne C; Adamson, Brynn C; Kinnett-Hopkins, Dominique; Bohri, Maria; Motl, Robert W

    2017-03-01

    There is increasing recognition that exercise is an efficacious strategy for managing many consequences of multiple sclerosis (MS), yet persons with MS are not engaging in sufficient exercise for accruing health benefits. Poor exercise uptake might be associated with the design of previous research. We conducted a randomised controlled trial (RCT) for examining the feasibility of a 4-month home-based, exercise-training program designed based on recent physical activity guidelines for MS and supplemented by behavioural strategies for compliance. Feasibility was assessed in the domains of process (e.g., recruitment), resource (e.g., monetary costs), management (e.g., personnel time requirements) and scientific outcomes (e.g., treatment effect). We recruited persons with mild-to-moderate MS who were randomised into an intervention or wait-list control condition. Intervention participants received a pedometer, elastic resistance bands, DVD, training manual, calendars, log-book, video coaching calls and newsletters. Participants in both conditions completed home-based assessments before and after the 4-month period. Ninety-nine persons with MS were assessed for eligibility, and 57 were randomised. Fifty-one persons completed the study (90%). Total costs of the study were US $5331.03. Personnel time to conduct the study totaled 263h. Participants in the intervention group complied fully with 71% of all exercise sessions. There was a moderate increase in self-reported exercise behaviour of the intervention participants as measured by the Godin Leisure-Time Exercise Questionnaire (d≥0.5). The results support the feasibility and acceptability of a home-based exercise intervention based on physical activity guidelines and supplemented with behavioural strategies for adults with mild-to-moderate MS.

  2. Computational methods of robust controller design for aerodynamic flutter suppression

    NASA Technical Reports Server (NTRS)

    Anderson, L. R.

    1981-01-01

    The development of Riccati iteration, a tool for the design and analysis of linear control systems is examined. First, Riccati iteration is applied to the problem of pole placement and order reduction in two-time scale control systems. Order reduction, yielding a good approximation to the original system, is demonstrated using a 16th order linear model of a turbofan engine. Next, a numerical method for solving the Riccati equation is presented and demonstrated for a set of eighth order random examples. A literature review of robust controller design methods follows which includes a number of methods for reducing the trajectory and performance index sensitivity in linear regulators. Lastly, robust controller design for large parameter variations is discussed.

  3. Variable Neural Adaptive Robust Control: A Switched System Approach

    SciTech Connect

    Lian, Jianming; Hu, Jianghai; Zak, Stanislaw H.

    2015-05-01

    Variable neural adaptive robust control strategies are proposed for the output tracking control of a class of multi-input multi-output uncertain systems. The controllers incorporate a variable-structure radial basis function (RBF) network as the self-organizing approximator for unknown system dynamics. The variable-structure RBF network solves the problem of structure determination associated with fixed-structure RBF networks. It can determine the network structure on-line dynamically by adding or removing radial basis functions according to the tracking performance. The structure variation is taken into account in the stability analysis of the closed-loop system using a switched system approach with the aid of the piecewise quadratic Lyapunov function. The performance of the proposed variable neural adaptive robust controllers is illustrated with simulations.

  4. Mitigation of Remedial Action Schemes by Decentralized Robust Governor Control

    SciTech Connect

    Elizondo, Marcelo A.; Marinovici, Laurentiu D.; Lian, Jianming; Kalsi, Karanjit; Du, Pengwei

    2014-04-15

    This paper presents transient stability improvement by a new distributed hierarchical control architecture (DHC). The integration of remedial action schemes (RAS) to the distributed hierarchical control architecture is studied. RAS in power systems are designed to maintain stability and avoid undesired system conditions by rapidly switching equipment and/or changing operating points according to predetermined rules. The acceleration trend relay currently in use in the US western interconnection is an example of RAS that trips generators to maintain transient stability. The link between RAS and DHC is through fast acting robust turbine/governor control that can also improve transient stability. In this paper, the influence of the decentralized robust turbine/governor control on the design of RAS is studied. Benefits of combining these two schemes are increasing power transfer capability and mitigation of RAS generator tripping actions; the later benefit is shown through simulations.

  5. Dental care resistance prevention and antibiotic prescribing modification—the cluster-randomised controlled DREAM trial

    PubMed Central

    2014-01-01

    Background Bacterial resistance development is one of the most urgent problems in healthcare worldwide. In Europe, dentistry accounts for a comparatively high amount of antibiotic prescriptions. In light of increasing levels of bacterial resistance, this development is alarming. So far, very few interventional studies have been performed, and further research is urgently needed. By means of a complex educational intervention, the DREAM trial aims at optimising antibiotic prescribing behaviour of general dentists in Germany. Method This is a cluster-randomised controlled trial, where each cluster consists of one dental practice and all of its patients in a defined period. Participants are general dentists practicing in the German region of Mecklenburg-Western Pomerania. Randomisation takes place after baseline data collection (6 months) and will be stratified by the antibiotic prescribing rates of the participating dental practices. Dentists randomised into the intervention group will participate in a complex small group educational seminar that aims at: increasing knowledge on bacterial resistance, pharmacology, and prophylaxis of infectious endocarditis; increasing awareness of dentist-patient communication using video-taped vignettes of dentist-patient communication on antibiotic treatment; improving collaboration between general dentists, general practitioners, and practice-based cardiologists on the necessity of antibiotic prophylaxis; enhancing awareness of the dentists’ own prescribing habits by providing antibiotic prescribing feedback; and increasing patient knowledge on antibiotic treatment by providing patient-centred information material on antibiotic prophylaxis of endocarditis. The dentists randomised into the control group will not receive any educational programme and provide care as usual. Primary outcome is the overall antibiotic prescribing rate measured at T1 (period of six months after intervention). In a subgroup of adult patients affected

  6. Does routine follow up after head injury help? A randomised controlled trial.

    PubMed Central

    Wade, D T; Crawford, S; Wenden, F J; King, N S; Moss, N E

    1997-01-01

    OBJECTIVE: To evaluate the Medical Disability Society's 1988 recommendation that "every patient attending hospital after a head injury should be registered and offered an outpatient follow up appointment" by determining whether offering a routine follow up service to patients presenting to hospital with a head injury of any severity affects outcome six months later. DESIGN: A randomised controlled trial design with masked assessment of outcome. SETTING: A mixed rural and urban health district with a population of about 560000. PATIENTS: 1156 consecutive patients resident in Oxfordshire aged between 16 and 65 years presenting over 13 months to accident and emergency departments or admitted to hospital and diagnosed as having a head injury of any severity, including those with other injuries. INTERVENTIONS: Patients were registered and randomised to one of two groups. Both groups continued to receive the standard service offered by the hospitals. The early follow up group were approached at 7-10 days after injury and offered additional information, advice, support, and further intervention as needed. All randomised patients were approached for follow up assessment six months after injury by independent clinicians blind to their group. MAIN OUTCOME MEASURES: Validated questionnaires were used to elicit ratings of post-concussion symptoms (the Rivermead postconcussion symptoms questionnaire), and changes in work, relationships, leisure, social, and domestic activities (the Rivermead head injury follow up questionnaire). RESULTS: The two groups were comparable at randomisation. Data was obtained at six months on 226 of 577 "control" patients and 252 of 579 "trial" patients (59% were lost to follow up). There were no significant differences overall between the trial and control groups at follow up, but subgroup analysis of the patients with moderate or severe head injuries (posttraumatic amnesia > or = one hour, or admitted to hospital), showed that those in the early

  7. Robust control design techniques for active flutter suppression

    NASA Technical Reports Server (NTRS)

    Ozbay, Hitay; Bachmann, Glen R.

    1994-01-01

    In this paper, an active flutter suppression problem is studied for a thin airfoil in unsteady aerodynamics. The mathematical model of this system is infinite dimensional because of Theodorsen's function which is irrational. Several second order approximations of Theodorsen's function are compared. A finite dimensional model is obtained from such an approximation. We use H infinity control techniques to find a robustly stabilizing controller for active flutter suppression.

  8. Robust trajectory tracking: differential game/cheap control approach

    NASA Astrophysics Data System (ADS)

    Turetsky, Vladimir; Glizer, Valery Y.; Shinar, Josef

    2014-11-01

    A robust trajectory tracking problem is treated in the framework of a zero-sum linear-quadratic differential game of a general type. For the cheap control version of this game, a novel solvability condition is derived. The sufficient condition, guaranteeing that the tracking problem is solved by the optimal strategy of the minimiser in the cheap control game, is established. The boundedness of the time realisations of this strategy is analysed. An illustrative example is presented.

  9. A Robust Cooperated Control Method with Reinforcement Learning and Adaptive H∞ Control

    NASA Astrophysics Data System (ADS)

    Obayashi, Masanao; Uchiyama, Shogo; Kuremoto, Takashi; Kobayashi, Kunikazu

    This study proposes a robust cooperated control method combining reinforcement learning with robust control to control the system. A remarkable characteristic of the reinforcement learning is that it doesn't require model formula, however, it doesn't guarantee the stability of the system. On the other hand, robust control system guarantees stability and robustness, however, it requires model formula. We employ both the actor-critic method which is a kind of reinforcement learning with minimal amount of computation to control continuous valued actions and the traditional robust control, that is, H∞ control. The proposed system was compared method with the conventional control method, that is, the actor-critic only used, through the computer simulation of controlling the angle and the position of a crane system, and the simulation result showed the effectiveness of the proposed method.

  10. A randomised controlled trial of group cognitive behavioural therapy for perfectionism.

    PubMed

    Handley, Alicia K; Egan, Sarah J; Kane, Robert T; Rees, Clare S

    2015-05-01

    Perfectionism is associated with symptoms of anxiety disorders, eating disorders and mood disorders. Treatments targeting perfectionism may reduce the symptoms of these disorders (Egan, Wade, & Shafran, 2011). This study is the first randomised controlled trial to investigate the efficacy of group cognitive behavioural therapy (CBT) for perfectionism. Forty-two participants with elevated perfectionism and a range of anxiety, eating and mood disorders were randomised to group CBT for perfectionism or a waitlist control. The treatment group reported significantly greater pre-post reductions in perfectionism, symptoms of depression, eating disorders, social anxiety, anxiety sensitivity and rumination, as well as significantly greater pre-post increases in self-esteem and quality of life compared to the waitlist control group. The impact of treatment on most of these outcomes was mediated by pre-post change in perfectionism (Concern over Mistakes). Treatment gains were reliable and clinically significant, and were maintained at 6-month follow-up. Findings support group CBT for perfectionism being an efficacious treatment for perfectionism and related psychopathology, as well as increasing self-esteem and quality of life.

  11. Feasibility of surgical randomised controlled trials with a placebo arm: a systematic review

    PubMed Central

    Wartolowska, Karolina; Collins, Gary S; Hopewell, Sally; Judge, Andrew; Dean, Benjamin J F; Rombach, Ines; Beard, David J; Carr, Andrew J

    2016-01-01

    Objectives To find evidence, either corroborating or refuting, for many persisting beliefs regarding the feasibility of carrying out surgical randomised controlled trials with a placebo arm, with emphasis on the challenges related to recruitment, funding, anaesthesia or blinding. Design Systematic review. Data sources and study selection The analysis involved studies published between 1959 and 2014 that were identified during an earlier systematic review of benefits and harms of placebo-controlled surgical trials published in 2014. Results 63 trials were included in the review. The main problem reported in many trials was a very slow recruitment rate, mainly due to the difficulty in finding eligible patients. Existing placebo trials were funded equally often from commercial and non-commercial sources. General anaesthesia or sedation was used in 41% of studies. Among the reviewed trials, 81% were double-blinded, and 19% were single-blinded. Across the reviewed trials, 96% (range 50–100%) of randomised patients completed the study. The withdrawal rate during the study was similar in the surgical and in the placebo groups. Conclusions This review demonstrated that placebo-controlled surgical trials are feasible, at least for procedures with a lower level of invasiveness, but also that recruitment is difficult. Many of the presumed challenges to undertaking such trials, for example, funding, anaesthesia or blinding of patients and assessors, were not reported as obstacles to completion in any of the reviewed trials. PMID:27008687

  12. The analgesic effect of sucrose in full term infants: a randomised controlled trial.

    PubMed Central

    Haouari, N.; Wood, C.; Griffiths, G.; Levene, M.

    1995-01-01

    OBJECTIVE--To evaluate the effects of different sucrose concentrations on measures of neonatal pain. DESIGN--Randomised, double blind, placebo controlled trial of sterile water (control) or one of three solutions of sucrose--namely, 12.5%, 25%, and 50% wt/vol. SETTING--Postnatal ward. PATIENTS--60 healthy infants of gestational age 37-42 weeks and postnatal age 1-6 days randomised to receive 2 ml of one of the four solutions on to the tongue two minutes before heel prick sampling for serum bilirubin concentrations. MAIN OUTCOME MEASURE--Duration of crying over the first three minutes after heel prick. RESULTS--There was a significant reduction in overall crying time and heart rate after three minutes in the babies given 50% sucrose as compared with controls. This was maximal one minute after heel prick in the 50% sucrose group and became statistically significant in the 25% sucrose group at two minutes. There was a significant trend for a reduction in crying time with increasing concentrations of sucrose over the first three minutes. CONCLUSION--Concentrated sucrose solution seems to reduce crying and the autonomic effects of a painful procedure in healthy normal babies. Sucrose may be a useful and safe analgesic for minor procedures in neonates. PMID:7787595

  13. Analysis and design of robust decentralized controllers for nonlinear systems

    SciTech Connect

    Schoenwald, D.A.

    1993-07-01

    Decentralized control strategies for nonlinear systems are achieved via feedback linearization techniques. New results on optimization and parameter robustness of non-linear systems are also developed. In addition, parametric uncertainty in large-scale systems is handled by sensitivity analysis and optimal control methods in a completely decentralized framework. This idea is applied to alleviate uncertainty in friction parameters for the gimbal joints on Space Station Freedom. As an example of decentralized nonlinear control, singular perturbation methods and distributed vibration damping are merged into a control strategy for a two-link flexible manipulator.

  14. 1-year follow-up of neurofeedback treatment in adolescents with attention-deficit hyperactivity disorder: randomised controlled trial

    PubMed Central

    Bongers, Ilja L.; Popma, Arne; Janssen, Tieme W.P.; van Nieuwenhuizen, Chijs

    2016-01-01

    Background Estimates of the effectiveness of neurofeedback as a treatment for attention-deficit hyperactivity disorder (ADHD) are mixed. Aims To investigate the long-term additional effects of neurofeedback (NFB) compared with treatment as usual (TAU) for adolescents with ADHD. Method Using a multicentre parallel-randomised controlled trial design, 60 adolescents with a DSM-IV-TR diagnosis of ADHD receiving NFB+TAU (n=41) or TAU (n=19) were followed up. Neurofeedback treatment consisted of approximately 37 sessions of theta/sensorimotor rhythm (SMR)-training on the vertex (Cz). Outcome measures included behavioural self-reports and neurocognitive measures. Allocation to the conditions was unmasked. Results At 1-year follow-up, inattention as reported by adolescents was decreased (range ηp2=0.23–0.36, P<0.01) and performance on neurocognitive tasks was faster (range ηp2=0.20–0.67, P<0.005) irrespective of treatment group. Conclusions Overall, NFB+TAU was as effective as TAU. Given the absence of robust additional effects of neurofeedback in the current study, results do not support the use of theta/SMR neurofeedback as a treatment for adolescents with ADHD and comorbid disorders in clinical practice. Declaration of interest None. Copyright and usage © The Royal College of Psychiatrists 2016. This is an open access article distributed under the terms of the Creative Commons Non-Commercial, No Derivatives (CC BY-NC-ND) licence. PMID:27703763

  15. Improving community ambulation after hip fracture: protocol for a randomised, controlled trial

    PubMed Central

    Orwig, D; Mangione, KK; Baumgarten, M; Terrin, M; Fortinsky, R; Kenny, AM; Gruber-Baldini, AL; Beamer, B; Tosteson, ANA; Shardell, M; Magder, L; Binder, E; Koval, K; Resnick, B; Craik, RL; Magaziner, J

    2017-01-01

    Introduction After a hip fracture in older persons, significant disability often remains; dependency in functional activities commonly persists beyond 3 months after surgery. Endurance, dynamic balance, quadriceps strength, and function are compromised, and contribute to an inability to walk independently in the community. In the United States, people aged 65 years and older are eligible to receive Medicare funding for physiotherapy for a limited time after a hip fracture. A goal of outpatient physiotherapy is independent and safe household ambulation 2 to 3 months after surgery. Current Medicare-reimbursed post-hip-fracture rehabilitation fails to return many patients to pre-fracture levels of function. Interventions delivered in the home after usual hip fracture physiotherapy has ended could promote higher levels of functional independence in these frail and older adult patients. Primary objective To evaluate the effect of a specific multicomponent physiotherapy intervention (PUSH), compared with a non-specific multi-component control physiotherapy intervention (PULSE), on the ability to ambulate independently in the community 16 weeks after randomisation. Design Parallel, two-group randomised multicentre trial of 210 older adults with a hip fracture assessed at baseline and 16 weeks after randomisation, and at 40 weeks after randomisation for a subset of approximately 150 participants. Participants and setting A total of 210 hip fracture patients are being enrolled at three clinical sites and randomised up to 26 weeks after admission. Study inclusion criteria are: closed, non-pathologic, minimal trauma hip fracture with surgical fixation; aged ≥ 60 years at the time of randomisation; community residing at the time of fracture and randomisation; ambulating without human assistance 2 months prior to fracture; and being unable to walk at least 300 m in 6 minutes at baseline. Participants are ineligible if the interventions are deemed to be unsafe or unfeasible

  16. Robust, Decoupled, Flight Control Design with Rate Saturating Actuators

    NASA Technical Reports Server (NTRS)

    Snell, S. A.; Hess, R. A.

    1997-01-01

    Techniques for the design of control systems for manually controlled, high-performance aircraft must provide the following: (1) multi-input, multi-output (MIMO) solutions, (2) acceptable handling qualities including no tendencies for pilot-induced oscillations, (3) a tractable approach for compensator design, (4) performance and stability robustness in the presence of significant plant uncertainty, and (5) performance and stability robustness in the presence actuator saturation (particularly rate saturation). A design technique built upon Quantitative Feedback Theory is offered as a candidate methodology which can provide flight control systems meeting these requirements, and do so over a considerable part of the flight envelope. An example utilizing a simplified model of a supermaneuverable fighter aircraft demonstrates the proposed design methodology.

  17. Decentralized adaptive control of robot manipulators with robust stabilization design

    NASA Technical Reports Server (NTRS)

    Yuan, Bau-San; Book, Wayne J.

    1988-01-01

    Due to geometric nonlinearities and complex dynamics, a decentralized technique for adaptive control for multilink robot arms is attractive. Lyapunov-function theory for stability analysis provides an approach to robust stabilization. Each joint of the arm is treated as a component subsystem. The adaptive controller is made locally stable with servo signals including proportional and integral gains. This results in the bound on the dynamical interactions with other subsystems. A nonlinear controller which stabilizes the system with uniform boundedness is used to improve the robustness properties of the overall system. As a result, the robot tracks the reference trajectories with convergence. This strategy makes computation simple and therefore facilitates real-time implementation.

  18. Graduated compression stockings to treat acute leg pain associated with proximal DVT. A randomised controlled trial.

    PubMed

    Kahn, S R; Shapiro, S; Ducruet, T; Wells, P S; Rodger, M A; Kovacs, M J; Anderson, D; Tagalakis, V; Morrison, D R; Solymoss, S; Miron, M-J; Yeo, E; Smith, R; Schulman, S; Kassis, J; Kearon, C; Chagnon, I; Wong, T; Demers, C; Hanmiah, R; Kaatz, S; Selby, R; Rathbun, S; Desmarais, S; Opatrny, L; Ortel, T L; Galanaud, J-P; Ginsberg, J S

    2014-12-01

    Acute deep venous thrombosis (DVT) causes leg pain. Elastic compression stockings (ECS) have potential to relieve DVT-related leg pain by diminishing the diameter of distended veins and increasing venous blood flow. It was our objective to determine whether ECS reduce leg pain in patients with acute DVT. We performed a secondary analysis of the SOX Trial, a multicentre randomised placebo controlled trial of active ECS versus placebo ECS to prevent the post-thrombotic syndrome.The study was performed in 24 hospital centres in Canada and the U.S. and included 803 patients with a first episode of acute proximal DVT. Patients were randomised to receive active ECS (knee length, 30-40 mm Hg graduated pressure) or placebo ECS (manufactured to look identical to active ECS, but lacking therapeutic compression). Study outcome was leg pain severity assessed on an 11-point numerical pain rating scale (0, no pain; 10, worst possible pain) at baseline, 14, 30 and 60 days after randomisation. Mean age was 55 years and 60% were male. In active ECS patients (n=409), mean (SD) pain severity at baseline and at 60 days were 5.18 (3.29) and 1.39 (2.19), respectively, and in placebo ECS patients (n=394) were 5.38 (3.29) and 1.13 (1.86), respectively. There were no significant differences in pain scores between groups at any assessment point, and no evidence for subgroup interaction by age, sex or anatomical extent of DVT. Results were similar in an analysis restricted to patients who reported wearing stockings every day. In conclusion, ECS do not reduce leg pain in patients with acute proximal DVT.

  19. Computerised cognitive behaviour therapy for depression in adolescents: study protocol for a feasibility randomised controlled trial

    PubMed Central

    Wright, Barry; Tindall, Lucy; Littlewood, Elizabeth; Adamson, Joy; Allgar, Victoria; Bennett, Sophie; Gilbody, Simon; Verduyn, Chrissie; Alderson-Day, Ben; Dyson, Lisa; Trépel, Dominic; Ali, Shehzad

    2014-01-01

    Introduction The 1 year prevalence of depression in adolescents is about 2%. Treatment with antidepressant medication is not recommended for initial treatment in young people due to concerns over high side effects, poor efficacy and addictive potential. Evidence suggests that cognitive behaviour therapy (CBT) is an effective treatment for depression and is currently one of the main treatment options recommended in adolescents. Given the affinity young people have with information technology they may be treated effectively, more widely and earlier in their illness evolution using computer-administered CBT (CCBT). Currently little is known about the clinical and resource implications of implementing CCBT within the National Health Service for adolescents with low mood/depression. We aim to establish the feasibility of running a fully powered randomised controlled trial (RCT). Methods and analysis Adolescents aged 12–18 with low mood/depression, (scoring ≥20 on the Mood and Feelings Questionnaire (MFQ)), will be approached to participate. Consenting participants will be randomised to either a CCBT programme (Stressbusters) or accessing selected websites providing information about low mood/depression. The primary outcome measure will be the Beck Depression Inventory (BDI). Participants will also complete generic health measures (EQ5D-Y, HUI2) and resource use questionnaires to examine the feasibility of cost-effectiveness analysis. Questionnaires will be completed at baseline, 4 and 12-month follow-ups. Progress and risk will be monitored via the MFQ administered at each treatment session. The acceptability of a CCBT programme to adolescents; and the willingness of clinicians to recruit participants and of participants to be randomised, recruitment rates, attrition rates and questionnaire completion rates will be collected for feasibility analysis. We will estimate ‘numbers needed’ to plan a fully powered RCT of clinical and cost-effectiveness. Ethics and

  20. Total ankle replacement versus arthrodesis (TARVA): protocol for a multicentre randomised controlled trial

    PubMed Central

    Goldberg, Andrew J; Zaidi, Razi; Thomson, Claire; Doré, Caroline J; Cro, Suzie; Round, Jeff; Molloy, Andrew; Davies, Mark; Karski, Michael; Kim, Louise; Cooke, Paul

    2016-01-01

    Introduction Total ankle replacement (TAR) or ankle arthrodesis (fusion) is the main surgical treatments for end-stage ankle osteoarthritis (OA). The popularity of ankle replacement is increasing while ankle fusion rates remain static. Both treatments have efficacy but to date all studies comparing the 2 have been observational without randomisation, and there are no published guidelines as to the most appropriate management. The TAR versus arthrodesis (TARVA) trial aims to compare the clinical and cost-effectiveness of TAR against ankle arthrodesis in the treatment of end-stage ankle OA in patients aged 50–85 years. Methods and analysis TARVA is a multicentre randomised controlled trial that will randomise 328 patients aged 50–85 years with end-stage ankle arthritis. The 2 arms of the study will be TAR or ankle arthrodesis with 164 patients in each group. Up to 16 UK centres will participate. Patients will have clinical assessments and complete questionnaires before their operation and at 6, 12, 26 and 52 weeks after surgery. The primary clinical outcome of the study is a validated patient-reported outcome measure, the Manchester Oxford foot questionnaire, captured preoperatively and 12 months after surgery. Secondary outcomes include quality-of-life scores, complications, revision, reoperation and a health economic analysis. Ethics and dissemination The protocol has been approved by the National Research Ethics Service Committee (London, Bloomsbury 14/LO/0807). This manuscript is based on V.5.0 of the protocol. The trial findings will be disseminated through peer-reviewed publications and conference presentations. Trial registration number NCT02128555. PMID:27601503

  1. Temporary sympathectomy in chronic refractory angina: a randomised, double-blind, placebo-controlled trial

    PubMed Central

    Denby, Christine; Eleuteri, Antonio; Tsang, Hoo kee; Leach, Austin; Hammond, Clare; Bridson, John D; Fisher, Michael; Elt, Matthew; Laflin, Robert; Fisher, Anthony C

    2015-01-01

    Background: Temporary sympathectomy by injection of bupivacaine at the site of the left stellate ganglion is used in the management of refractory angina at several UK centres. Although patients frequently report significant reduction in symptoms, efficacy has not been established by double-blind, randomised placebo-controlled trial (RCT). Objective: To investigate the efficacy of the procedure for the first time by a double-blind RCT. Methods: Consecutive patients referred to the authors’ National Health Service (NHS) angina centre who were candidates for temporary sympathectomy were invited to participate in a trial. A total of 65 patients were randomised to receive either bupivacaine or saline injections. Identical syringes were prepared remotely, blinding patients and staff from randomisation. Cardiac autonomic function was measured 3 hours pre- and post-injection using new heart rate variability (HRV) analyses. Angina episodes were recorded contemporaneously by patients in study diaries in the 7-day periods pre- and post-injection. Results: In 51 patients suitable for analysis, no significant differences between the active and placebo groups were found in patient-recorded frequency or intensity of angina episodes pre- and post-injection. However, across both groups combined, a significant difference was found in the frequency of angina episodes pre- and post-injection. Conclusion: The reduction in frequency of angina episodes produced by this procedure may not be due to drug pharmacology. It may be a placebo response or due to the mechanical effects of the injection of fluid. There is a need for further work using a larger patient cohort considering both mechanical and psychological factors. PMID:26516570

  2. Advance care planning in patients with incurable cancer: study protocol for a randomised controlled trial

    PubMed Central

    Clayton, Josephine; Butow, Phyllis N; Silvester, William; Detering, Karen; Hall, Jane; Kiely, Belinda E; Cebon, Jonathon; Clarke, Stephen; Bell, Melanie L; Stockler, Martin; Beale, Phillip; Tattersall, Martin H N

    2016-01-01

    Introduction There is limited evidence documenting the effectiveness of Advance Care Planning (ACP) in cancer care. The present randomised trial is designed to evaluate whether the administration of formal ACP improves compliance with patients' end-of-life (EOL) wishes and patient and family satisfaction with care. Methods and analysis A randomised control trial in eight oncology centres across New South Wales and Victoria, Australia, is designed to assess the efficacy of a formal ACP intervention for patients with cancer. Patients with incurable cancer and an expected survival of 3–12 months, plus a nominated family member or friend will be randomised to receive either standard care or standard care plus a formal ACP intervention. The project sample size is 210 patient–family/friend dyads. The primary outcome measure is family/friend-reported: (1) discussion with the patient about their EOL wishes and (2) perception that the patient's EOL wishes were met. Secondary outcome measures include: documentation of and compliance with patient preferences for medical intervention at the EOL; the family/friend's perception of the quality of the patient's EOL care; the impact of death on surviving family; patient–family and patient–healthcare provider communication about EOL care; patient and family/friend satisfaction with care; quality of life of patient and family/friend subsequent to trial entry, the patient's strength of preferences for quality of life and length of life; the costs of care subsequent to trial entry and place of death. Ethics and dissemination Ethical approval was received from the Sydney Local Health District (RPA Zone) Human Research Ethical Committee, Australia (Protocol number X13-0064). Study results will be submitted for publication in peer-reviewed journals and presented at national and international conferences. Trial registration number Pre-results; ACTRN12613001288718. PMID:27909034

  3. Robustness of Controllability for Networks Based on Edge-Attack

    PubMed Central

    Nie, Sen; Wang, Xuwen; Zhang, Haifeng; Li, Qilang; Wang, Binghong

    2014-01-01

    We study the controllability of networks in the process of cascading failures under two different attacking strategies, random and intentional attack, respectively. For the highest-load edge attack, it is found that the controllability of Erdős-Rényi network, that with moderate average degree, is less robust, whereas the Scale-free network with moderate power-law exponent shows strong robustness of controllability under the same attack strategy. The vulnerability of controllability under random and intentional attacks behave differently with the increasing of removal fraction, especially, we find that the robustness of control has important role in cascades for large removal fraction. The simulation results show that for Scale-free networks with various power-law exponents, the network has larger scale of cascades do not mean that there will be more increments of driver nodes. Meanwhile, the number of driver nodes in cascading failures is also related to the edges amount in strongly connected components. PMID:24586507

  4. Reducing Postpartum Weight Retention and Improving Breastfeeding Outcomes in Overweight Women: A Pilot Randomised Controlled Trial

    PubMed Central

    Martin, Julia; MacDonald-Wicks, Lesley; Hure, Alexis; Smith, Roger; Collins, Clare E

    2015-01-01

    Overweight and obesity is prevalent among women of reproductive age (42% BMI > 25 kg/m2) and parity is associated with risk of weight gain. Weight gain greater than that recommended by the Institute of Medicine (IOM )is also associated with lower rates of breastfeeding initiation and duration in women. The aim of this pilot randomised controlled trial is to examine the feasibility of recruiting and maintaining a cohort of pregnant women with the view of reducing postpartum weight retention and improving breastfeeding outcomes. Women (BMI of 25–35 kg/m2 (n = 36)) were recruited from the John Hunter Hospital antenatal clinic in New South Wales, Australia. Participants were stratified by BMI and randomised to one of three groups with follow-up to six months postpartum. Women received a dietary intervention with or without breastfeeding support from a lactation consultant, or were assigned to a wait-list control group where the dietary intervention was issued at three months postpartum. Feasibility and acceptability was assessed by participation rates and questionnaire. Analysis of variance and covariance was conducted to determine any differences between groups. Sixty-nine per cent of the participants were still enrolled at six months postpartum. This pilot demonstrated some difficulties in recruiting women from antenatal clinics and retaining them in the trial. Although underpowered; the results on weight; biomarkers and breastfeeding outcomes indicated improved metabolic health. PMID:25723973

  5. Robust control of burst suppression for medical coma

    NASA Astrophysics Data System (ADS)

    Westover, M. Brandon; Kim, Seong-Eun; Ching, ShiNung; Purdon, Patrick L.; Brown, Emery N.

    2015-08-01

    Objective. Medical coma is an anesthetic-induced state of brain inactivation, manifest in the electroencephalogram by burst suppression. Feedback control can be used to regulate burst suppression, however, previous designs have not been robust. Robust control design is critical under real-world operating conditions, subject to substantial pharmacokinetic and pharmacodynamic parameter uncertainty and unpredictable external disturbances. We sought to develop a robust closed-loop anesthesia delivery (CLAD) system to control medical coma. Approach. We developed a robust CLAD system to control the burst suppression probability (BSP). We developed a novel BSP tracking algorithm based on realistic models of propofol pharmacokinetics and pharmacodynamics. We also developed a practical method for estimating patient-specific pharmacodynamics parameters. Finally, we synthesized a robust proportional integral controller. Using a factorial design spanning patient age, mass, height, and gender, we tested whether the system performed within clinically acceptable limits. Throughout all experiments we subjected the system to disturbances, simulating treatment of refractory status epilepticus in a real-world intensive care unit environment. Main results. In 5400 simulations, CLAD behavior remained within specifications. Transient behavior after a step in target BSP from 0.2 to 0.8 exhibited a rise time (the median (min, max)) of 1.4 [1.1, 1.9] min; settling time, 7.8 [4.2, 9.0] min; and percent overshoot of 9.6 [2.3, 10.8]%. Under steady state conditions the CLAD system exhibited a median error of 0.1 [-0.5, 0.9]%; inaccuracy of 1.8 [0.9, 3.4]%; oscillation index of 1.8 [0.9, 3.4]%; and maximum instantaneous propofol dose of 4.3 [2.1, 10.5] mg kg-1. The maximum hourly propofol dose was 4.3 [2.1, 10.3] mg kg-1 h-1. Performance fell within clinically acceptable limits for all measures. Significance. A CLAD system designed using robust control theory achieves clinically acceptable

  6. Modeling, Robust Control, and Experimental Validation of a Supercavitating Vehicle

    NASA Astrophysics Data System (ADS)

    Escobar Sanabria, David

    This dissertation considers the mathematical modeling, control under uncertainty, and experimental validation of an underwater supercavitating vehicle. By traveling inside a gas cavity, a supercavitating vehicle reduces hydrodynamic drag, increases speed, and minimizes power consumption. The attainable speed and power efficiency make these vehicles attractive for undersea exploration, high-speed transportation, and defense. However, the benefits of traveling inside a cavity come with difficulties in controlling the vehicle dynamics. The main challenge is the nonlinear force that arises when the back-end of the vehicle pierces the cavity. This force, referred to as planing, leads to oscillatory motion and instability. Control technologies that are robust to planing and suited for practical implementation need to be developed. To enable these technologies, a low-order vehicle model that accounts for inaccuracy in the characterization of planing is required. Additionally, an experimental method to evaluate possible pitfalls in the models and controllers is necessary before undersea testing. The major contribution of this dissertation is a unified framework for mathematical modeling, robust control synthesis, and experimental validation of a supercavitating vehicle. First, we introduce affordable experimental methods for mathematical modeling and controller testing under planing and realistic flow conditions. Then, using experimental observations and physical principles, we create a low-order nonlinear model of the longitudinal vehicle motion. This model quantifies the planing uncertainty and is suitable for robust controller synthesis. Next, based on the vehicle model, we develop automated tools for synthesizing controllers that deliver a certificate of performance in the face of nonlinear and uncertain planing forces. We demonstrate theoretically and experimentally that the proposed controllers ensure higher performance when the uncertain planing dynamics are

  7. A general framework for robust control in fluid mechanics

    NASA Astrophysics Data System (ADS)

    Bewley, Thomas R.; Temam, Roger; Ziane, Mohammed

    2000-04-01

    The application of optimal control theory to complex problems in fluid mechanics has proven to be quite effective when complete state information from high-resolution numerical simulations is available [P. Moin, T.R. Bewley, Appl. Mech. Rev., Part 2 47 (6) (1994) S3-S13; T.R. Bewley, P. Moin, R. Temam, J. Fluid Mech. (1999), submitted for publication]. In this approach, an iterative optimization algorithm based on the repeated computation of an adjoint field is used to optimize the controls for finite-horizon nonlinear flow problems [F. Abergel, R. Temam, Theoret. Comput. Fluid Dyn. 1 (1990) 303-325]. In order to extend this infinite-dimensional optimization approach to control externally disturbed flows in which the controls must be determined based on limited noisy flow measurements alone, it is necessary that the controls computed be insensitive to both state disturbances and measurement noise. For this reason, robust control theory, a generalization of optimal control theory, has been examined as a technique by which effective control algorithms which are insensitive to a broad class of external disturbances may be developed for a wide variety of infinite-dimensional linear and nonlinear problems in fluid mechanics. An aim of the present paper is to put such algorithms into a rigorous mathematical framework, for it cannot be assumed at the outset that a solution to the infinite-dimensional robust control problem even exists. In this paper, conditions on the initial data, the parameters in the cost functional, and the regularity of the problem are established such that existence and uniqueness of the solution to the robust control problem can be proven. Both linear and nonlinear problems are treated, and the 2D and 3D nonlinear cases are treated separately in order to get the best possible estimates. Several generalizations are discussed and an appropriate numerical method is proposed.

  8. Decentralized robust nonlinear model predictive controller for unmanned aerial systems

    NASA Astrophysics Data System (ADS)

    Garcia Garreton, Gonzalo A.

    The nonlinear and unsteady nature of aircraft aerodynamics together with limited practical range of controls and state variables make the use of the linear control theory inadequate especially in the presence of external disturbances, such as wind. In the classical approach, aircraft are controlled by multiple inner and outer loops, designed separately and sequentially. For unmanned aerial systems in particular, control technology must evolve to a point where autonomy is extended to the entire mission flight envelope. This requires advanced controllers that have sufficient robustness, track complex trajectories, and use all the vehicles control capabilities at higher levels of accuracy. In this work, a robust nonlinear model predictive controller is designed to command and control an unmanned aerial system to track complex tight trajectories in the presence of internal and external perturbance. The Flight System developed in this work achieves the above performance by using: 1. A nonlinear guidance algorithm that enables the vehicle to follow an arbitrary trajectory shaped by moving points; 2. A formulation that embeds the guidance logic and trajectory information in the aircraft model, avoiding cross coupling and control degradation; 3. An artificial neural network, designed to adaptively estimate and provide aerodynamic and propulsive forces in real-time; and 4. A mixed sensitivity approach that enhances the robustness for a nonlinear model predictive controller overcoming the effect of un-modeled dynamics, external disturbances such as wind, and measurement additive perturbations, such as noise and biases. These elements have been integrated and tested in simulation and with previously stored flight test data and shown to be feasible.

  9. Robust sliding mode continuous control of an IM drive

    SciTech Connect

    Jezernik, K.; Hren, A.; Drevensek, D.

    1995-12-31

    A control approach for robust trajectory tracking of IM servodrive based on the variable structure systems (VSS) is described. A new discrete-time control algorithm has been developed by combining VSS and Lyapunov design. It possesses all the good properties of the sliding mode and avoids the unnecessary discontinuity of the control input, thus eliminating chattering which has been considering as serious obstacles for applications of VSS. A unified control approach for current, torque and motion control based on the discrete-time sliding mode for application in indirect vector control of an IM drive is developed. The sliding mode approach can be applied to the control of an Im drive due to the replacement of the hysteresis controller with widely used PWM technique. All the theoretical issues are verified by experiment. The experimental system consists of a transputer and a microcontroller, thus allowing parallel processing.

  10. Intensive Patient Education Improves Glycaemic Control in Diabetes Compared to Conventional Education: A Randomised Controlled Trial in a Nigerian Tertiary Care Hospital

    PubMed Central

    Essien, Okon; Otu, Akaninyene; Umoh, Victor; Enang, Ofem; Hicks, Joseph Paul; Walley, John

    2017-01-01

    Background Diabetes is now a global epidemic, but most cases are now in low- and middle-income countries. Diabetes self-management education (DSME) is key to enabling patients to manage their chronic condition and can reduce the occurrence of costly and devastating complications. However, there is limited evidence on the effectiveness of different DSME programmes in resource limited settings. Methods We conducted an unblinded, parallel-group, individually-randomised controlled trial at the University of Calabar Teaching Hospital (Nigeria) to evaluate whether an intensive and systematic DSME programme, using structured guidelines, improved glycaemic control compared to the existing ad hoc patient education (clinical practice was unchanged). Eligible patients (≥18 years, HbA1c > 8.5% and physically able to participate) were randomly allocated by permuted block randomisation to participate for six months in either an intensive or conventional education group. The primary outcome was HbA1c (%) at six-months. Results We randomised 59 participants to each group and obtained six-month HbA1c outcomes from 53 and 51 participants in the intensive and conventional education groups, respectively. Intensive group participants had a mean six-month HbA1c (%) of 8.4 (95% CI: 8 to 8.9), while participants in the conventional education group had a mean six-month HbA1c (%) of 10.2 (95% CI: 9.8 to 10.7). The difference was statistically (P < 0.0001) and clinically significant, with intensive group participants having HbA1c outcomes on average -1.8 (95% CI: -2.4 to -1.2) percentage points lower than conventional group participants. Results were robust to adjustment for a range of covariates and multiple imputation of missing outcome data. Conclusions This study demonstrates the effectiveness of a structured, guideline-based DSME intervention in a LMIC setting versus a pragmatic comparator. The intervention is potentially replicable at other levels of the Nigerian healthcare system

  11. Robust Feedback Control of Flow Induced Structural Radiation of Sound

    NASA Technical Reports Server (NTRS)

    Heatwole, Craig M.; Bernhard, Robert J.; Franchek, Matthew A.

    1997-01-01

    A significant component of the interior noise of aircraft and automobiles is a result of turbulent boundary layer excitation of the vehicular structure. In this work, active robust feedback control of the noise due to this non-predictable excitation is investigated. Both an analytical model and experimental investigations are used to determine the characteristics of the flow induced structural sound radiation problem. The problem is shown to be broadband in nature with large system uncertainties associated with the various operating conditions. Furthermore the delay associated with sound propagation is shown to restrict the use of microphone feedback. The state of the art control methodologies, IL synthesis and adaptive feedback control, are evaluated and shown to have limited success for solving this problem. A robust frequency domain controller design methodology is developed for the problem of sound radiated from turbulent flow driven plates. The control design methodology uses frequency domain sequential loop shaping techniques. System uncertainty, sound pressure level reduction performance, and actuator constraints are included in the design process. Using this design method, phase lag was added using non-minimum phase zeros such that the beneficial plant dynamics could be used. This general control approach has application to lightly damped vibration and sound radiation problems where there are high bandwidth control objectives requiring a low controller DC gain and controller order.

  12. Robust Concentration and Frequency Control in Oscillatory Homeostats

    PubMed Central

    Thorsen, Kristian; Agafonov, Oleg; Selstø, Christina H.; Jolma, Ingunn W.; Ni, Xiao Y.; Drengstig, Tormod; Ruoff, Peter

    2014-01-01

    Homeostatic and adaptive control mechanisms are essential for keeping organisms structurally and functionally stable. Integral feedback is a control theoretic concept which has long been known to keep a controlled variable robustly (i.e. perturbation-independent) at a given set-point by feeding the integrated error back into the process that generates . The classical concept of homeostasis as robust regulation within narrow limits is often considered as unsatisfactory and even incompatible with many biological systems which show sustained oscillations, such as circadian rhythms and oscillatory calcium signaling. Nevertheless, there are many similarities between the biological processes which participate in oscillatory mechanisms and classical homeostatic (non-oscillatory) mechanisms. We have investigated whether biological oscillators can show robust homeostatic and adaptive behaviors, and this paper is an attempt to extend the homeostatic concept to include oscillatory conditions. Based on our previously published kinetic conditions on how to generate biochemical models with robust homeostasis we found two properties, which appear to be of general interest concerning oscillatory and homeostatic controlled biological systems. The first one is the ability of these oscillators (“oscillatory homeostats”) to keep the average level of a controlled variable at a defined set-point by involving compensatory changes in frequency and/or amplitude. The second property is the ability to keep the period/frequency of the oscillator tuned within a certain well-defined range. In this paper we highlight mechanisms that lead to these two properties. The biological applications of these findings are discussed using three examples, the homeostatic aspects during oscillatory calcium and p53 signaling, and the involvement of circadian rhythms in homeostatic regulation. PMID:25238410

  13. Adaptive robust control of longitudinal and transverse electron beam profiles

    NASA Astrophysics Data System (ADS)

    Rezaeizadeh, Amin; Schilcher, Thomas; Smith, Roy S.

    2016-05-01

    Feedback control of the longitudinal and transverse electron beam profiles are considered to be critical for beam control in accelerators. In the feedback scheme, the longitudinal or transverse beam profile is measured and compared to a desired profile to give an error estimate. The error is then used to act on the appropriate actuators to correct the profile. The role of the transverse feedback is to steer the beam in a particular trajectory, known as the "orbit." The common approach for orbit correction is based on approximately inverting the response matrix, and in the best case, involves regulating or filtering the singular values. In the current contribution, a more systematic and structured way of handling orbit correction is introduced giving robustness against uncertainties in the response matrix. Moreover, the input bounds are treated to avoid violating the limits of the corrector currents. The concept of the robust orbit correction has been successfully tested at the SwissFEL injector test facility. In the SwissFEL machine, a photo-injector laser system extracts electrons from a cathode and a similar robust control method is developed for the longitudinal feedback control of the current profile of the electron bunch. The method manipulates the angles of the crystals in the laser system to produce a desired charge distribution over the electron bunch length. This approach paves the way towards automation of laser pulse stacking.

  14. Limiting weight gain in overweight and obese women during pregnancy to improve health outcomes: the LIMIT randomised controlled trial

    PubMed Central

    2011-01-01

    Background Obesity is a significant global health problem, with the proportion of women entering pregnancy with a body mass index greater than or equal to 25 kg/m2 approaching 50%. Obesity during pregnancy is associated with a well-recognised increased risk of adverse health outcomes both for the woman and her infant, however there is more limited information available regarding effective interventions to improve health outcomes. The aims of this randomised controlled trial are to assess whether the implementation of a package of dietary and lifestyle advice to overweight and obese women during pregnancy to limit gestational weight gain is effective in improving maternal, fetal and infant health outcomes. Methods/Design Design: Multicentred randomised, controlled trial. Inclusion Criteria: Women with a singleton, live gestation between 10+0-20+0 weeks who are obese or overweight (defined as body mass index greater than or equal to 25 kg/m2), at the first antenatal visit. Trial Entry & Randomisation: Eligible, consenting women will be randomised between 10+0 and 20+0 weeks gestation using a central telephone randomisation service, and randomisation schedule prepared by non-clinical research staff with balanced variable blocks. Stratification will be according to maternal BMI at trial entry, parity, and centre where planned to give birth. Treatment Schedules: Women randomised to the Dietary and Lifestyle Advice Group will receive a series of inputs from research assistants and research dietician to limit gestational weight gain, and will include a combination of dietary, exercise and behavioural strategies. Women randomised to the Standard Care Group will continue to receive their pregnancy care according to local hospital guidelines, which does not currently include routine provision of dietary, lifestyle and behavioural advice. Outcome assessors will be blinded to the allocated treatment group. Primary Study Outcome: infant large for gestational age (defined as

  15. The effects of the Bowen technique on hamstring flexibility over time: a randomised controlled trial.

    PubMed

    Marr, Michelle; Baker, Julian; Lambon, Nicky; Perry, Jo

    2011-07-01

    The hamstring muscles are regularly implicated in recurrent injuries, movement dysfunction and low back pain. Links between limited flexibility and development of neuromusculoskeletal symptoms are frequently reported. The Bowen Technique is used to treat many conditions including lack of flexibility. The study set out to investigate the effect of the Bowen Technique on hamstring flexibility over time. An assessor-blind, prospective, randomised controlled trial was performed on 120 asymptomatic volunteers. Participants were randomly allocated into a control group or Bowen group. Three flexibility measurements occurred over one week, using an active knee extension test. The intervention group received a single Bowen treatment. A repeated measures univariate analysis of variance, across both groups for the three time periods, revealed significant within-subject and between-subject differences for the Bowen group. Continuing increases in flexibility levels were observed over one week. No significant change over time was noted for the control group.

  16. Robust adaptive backstepping control for reentry reusable launch vehicles

    NASA Astrophysics Data System (ADS)

    Wang, Zhen; Wu, Zhong; Du, Yijiang

    2016-09-01

    During the reentry process of reusable launch vehicles (RLVs), the large range of flight envelope will not only result in high nonlinearities, strong coupling and fast time-varying characteristics of the attitude dynamics, but also result in great uncertainties in the atmospheric density, aerodynamic coefficients and environmental disturbances, etc. In order to attenuate the effects of these problems on the control performance of the reentry process, a robust adaptive backstepping control (RABC) strategy is proposed for RLV in this paper. This strategy consists of two-loop controllers designed via backstepping method. Both the outer and the inner loop adopt a robust adaptive controller, which can deal with the disturbances and uncertainties by the variable-structure term with the estimation of their bounds. The outer loop can track the desired attitude by the design of virtual control-the desired angular velocity, while the inner one can track the desired angular velocity by the design of control torque. Theoretical analysis indicates that the closed-loop system under the proposed control strategy is globally asymptotically stable. Even if the boundaries of the disturbances and uncertainties are unknown, the attitude can track the desired value accurately. Simulation results of a certain RLV demonstrate the effectiveness of the control strategy.

  17. Parametric uncertainty modeling for application to robust control

    NASA Technical Reports Server (NTRS)

    Belcastro, Christine M.; Chang, B.-C.; Fischl, Robert

    1993-01-01

    Viewgraphs and a paper on parametric uncertainty modeling for application to robust control are included. Advanced robust control system analysis and design is based on the availability of an uncertainty description which separates the uncertain system elements from the nominal system. Although this modeling structure is relatively straightforward to obtain for multiple unstructured uncertainties modeled throughout the system, it is difficult to formulate for many problems involving real parameter variations. Furthermore, it is difficult to ensure that the uncertainty model is formulated such that the dimension of the resulting model is minimal. A procedure for obtaining an uncertainty model for real uncertain parameter problems in which the uncertain parameters can be represented in a multilinear form is presented. Furthermore, the procedure is formulated such that the resulting uncertainty model is minimal (or near minimal) relative to a given state space realization of the system. The approach is demonstrated for a multivariable third-order example problem having four uncertain parameters.

  18. Frequency domain identification for robust large space structure control design

    NASA Technical Reports Server (NTRS)

    Yam, Y.; Bayard, D. S.; Scheid, R. E.

    1991-01-01

    A methodology is demonstrated for frequency domain identification of large space structures which systematically transforms experimental raw data into a form required for synthesizing H(infinity) controllers using modern robust control design software (e.g., Matlab Toolboxes). A unique feature of this approach is that the additive uncertainty is characterized to a specified statistic confidence rather than with hard bounds. In this study, the difference in robust performance is minimal between the two levels of confidence. In general cases, the present methodology provides a tool for performance/confidence level tradeoff studies. For simplicity, the additive uncertainty on a frequency grid is considered and the interpolation error in between grid points is neglected.

  19. Anticipated regret to increase uptake of colorectal cancer screening (ARTICS): A randomised controlled trial

    PubMed Central

    O'Carroll, Ronan E.; Chambers, Julie A.; Brownlee, Linda; Libby, Gillian; Steele, Robert J.C.

    2015-01-01

    Screening is important for early detection of colorectal cancer. Our aim was to determine whether a simple anticipated regret (AR) intervention could increase uptake of colorectal cancer screening. A randomised controlled trial of a simple, questionnaire-based AR intervention, delivered alongside existing pre-notification letters, was conducted. A total of 60,000 adults aged 50–74 years from the Scottish National Screening programme were randomised into the following groups: (1) no questionnaire (control), (2) Health Locus of Control questionnaire (HLOC) or (3) HLOC plus AR questionnaire. The primary outcome was return of the guaiac faecal occult blood test (FOBT). The secondary outcomes included intention to return test kit and perceived disgust (ICK). A total of 59,366 people were analysed as allocated (intention-to-treat (ITT)); no overall differences were seen between the treatment groups on FOBT uptake (control: 57.3%, HLOC: 56.9%, AR: 57.4%). In total, 13,645 (34.2%) individuals returned the questionnaires. Analysis of the secondary questionnaire measures showed that AR indirectly affected FOBT uptake via intention, whilst ICK directly affected FOBT uptake over and above intention. The effect of AR on FOBT uptake was also moderated by intention strength: for less-than-strong intenders only, uptake was 4.2% higher in the AR (84.6%) versus the HLOC group (80.4%) (95% CI for difference (2.0, 6.5)). The findings show that psychological concepts including AR and perceived disgust (ICK) are important factors in determining FOBT uptake. However, the AR intervention had no simple effect in the ITT analysis. It can be concluded that, in those with low intentions, exposure to AR may be required to increase FOBT uptake. The current controlled trials are presented at the website www.controlled-trials.com (number: ISRCTN74986452). PMID:26301484

  20. Improving outcomes of preschool language delay in the community: protocol for the Language for Learning randomised controlled trial

    PubMed Central

    2012-01-01

    Background Early language delay is a high-prevalence condition of concern to parents and professionals. It may result in lifelong deficits not only in language function, but also in social, emotional/behavioural, academic and economic well-being. Such delays can lead to considerable costs to the individual, the family and to society more widely. The Language for Learning trial tests a population-based intervention in 4 year olds with measured language delay, to determine (1) if it improves language and associated outcomes at ages 5 and 6 years and (2) its cost-effectiveness for families and the health care system. Methods/Design A large-scale randomised trial of a year-long intervention targeting preschoolers with language delay, nested within a well-documented, prospective, population-based cohort of 1464 children in Melbourne, Australia. All children received a 1.25-1.5 hour formal language assessment at their 4th birthday. The 200 children with expressive and/or receptive language scores more than 1.25 standard deviations below the mean were randomised into intervention or ‘usual care’ control arms. The 20-session intervention program comprises 18 one-hour home-based therapeutic sessions in three 6-week blocks, an outcome assessment, and a final feed-back/forward planning session. The therapy utilises a ‘step up-step down’ therapeutic approach depending on the child’s language profile, severity and progress, with standardised, manualised activities covering the four language development domains of: vocabulary and grammar; narrative skills; comprehension monitoring; and phonological awareness/pre-literacy skills. Blinded follow-up assessments at ages 5 and 6 years measure the primary outcome of receptive and expressive language, and secondary outcomes of vocabulary, narrative, and phonological skills. Discussion A key strength of this robust study is the implementation of a therapeutic framework that provides a standardised yet tailored approach for

  1. Robust control charts in industrial production of olive oil

    NASA Astrophysics Data System (ADS)

    Grilo, Luís M.; Mateus, Dina M. R.; Alves, Ana C.; Grilo, Helena L.

    2014-10-01

    Acidity is one of the most important variables in the quality analysis and characterization of olive oil. During the industrial production we use individuals and moving range charts to monitor this variable, which is not always normal distributed. After a brief exploratory data analysis, where we use the bootstrap method, we construct control charts, before and after a Box-Cox transformation, and compare their robustness and performance.

  2. Study Protocol: Screening and Treatment of Alcohol-Related Trauma (START) – a randomised controlled trial

    PubMed Central

    2012-01-01

    Background The incidence of mandibular fractures in the Northern Territory of Australia is very high, especially among Indigenous people. Alcohol intoxication is implicated in the majority of facial injuries, and substance use is therefore an important target for secondary prevention. The current study tests the efficacy of a brief therapy, Motivational Care Planning, in improving wellbeing and substance misuse in youth and adults hospitalised with alcohol-related facial trauma. Methods and design The study is a randomised controlled trial with 6 months of follow-up, to examine the effectiveness of a brief and culturally adapted intervention in improving outcomes for trauma patients with at-risk drinking admitted to the Royal Darwin Hospital maxillofacial surgery unit. Potential participants are identified using AUDIT-C questionnaire. Eligible participants are randomised to either Motivational Care Planning (MCP) or Treatment as Usual (TAU). The outcome measures will include quantity and frequency of alcohol and other substance use by Timeline Followback. The recruitment target is 154 participants, which with 20% dropout, is hoped to provide 124 people receiving treatment and follow-up. Discussion This project introduces screening and brief interventions for high-risk drinkers admitted to the hospital with facial trauma. It introduces a practical approach to integrating brief interventions in the hospital setting, and has potential to demonstrate significant benefits for at-risk drinkers with facial trauma. Trial Registration The trial has been registered in Australian New Zealand Clinical Trials Registry (ANZCTR) and Trial Registration: ACTRN12611000135910. PMID:23106916

  3. Randomised controlled trial of qigong in the treatment of mild essential hypertension.

    PubMed

    Cheung, B M Y; Lo, J L F; Fong, D Y T; Chan, M Y; Wong, S H T; Wong, V C W; Lam, K S L; Lau, C P; Karlberg, J P E

    2005-09-01

    Exercise and relaxation decrease blood pressure. Qigong is a traditional Chinese exercise consisting of breathing and gentle movements. We conducted a randomised controlled trial to study the effect of Guolin qigong on blood pressure. In all, 88 patients with mild essential hypertension were recruited from the community and randomised to Goulin qigong or conventional exercise for 16 weeks. The main outcome measurements were blood pressure, health status (SF-36 scores), Beck Anxiety and Depression Inventory scores. In the qigong group, blood pressure decreased significantly from 146.3+/-7.8/93.0+/-4.1 mmHg at baseline to 135.5+/-10.0/87.1+/-7.7 mmHg at week 16. In the exercise group, blood pressure also decreased significantly from 140.9+/-10.9/93.1+/-3.5 mmHg to 129.7+/-11.1/86.0+/-7.0 mmHg. Heart rate, weight, BMI, waist circumference, total cholesterol, renin and 24 h urinary albumin excretion significantly decreased in both groups after 16 weeks. General health, bodily pain, social functioning and depression also improved in both groups. No significant differences between qigong and conventional exercise were found. In conclusion, Guolin qigong and conventional exercise have similar effects on blood pressure in patients with mild hypertension. While no additional benefits were identified, it is nevertheless an alternative to conventional exercise in the nondrug treatment of hypertension.

  4. Comparison of Bobath based and movement science based treatment for stroke: a randomised controlled trial

    PubMed Central

    van Vliet, P M; Lincoln, N; Foxall, A

    2005-01-01

    Objectives: Bobath based (BB) and movement science based (MSB) physiotherapy interventions are widely used for patients after stroke. There is little evidence to suggest which is most effective. This single-blind randomised controlled trial evaluated the effect of these treatments on movement abilities and functional independence. Methods: A total of 120 patients admitted to a stroke rehabilitation ward were randomised into two treatment groups to receive either BB or MSB treatment. Primary outcome measures were the Rivermead Motor Assessment and the Motor Assessment Scale. Secondary measures assessed functional independence, walking speed, arm function, muscle tone, and sensation. Measures were performed by a blinded assessor at baseline, and then at 1, 3, and 6 months after baseline. Analysis of serial measurements was performed to compare outcomes between the groups by calculating the area under the curve (AUC) and inserting AUC values into Mann-Whitney U tests. Results: Comparison between groups showed no significant difference for any outcome measures. Significance values for the Rivermead Motor Assessment ranged from p = 0.23 to p = 0.97 and for the Motor Assessment Scale from p = 0.29 to p = 0.87. Conclusions: There were no significant differences in movement abilities or functional independence between patients receiving a BB or an MSB intervention. Therefore the study did not show that one approach was more effective than the other in the treatment of stroke patients. PMID:15774435

  5. Short-burst oxygen therapy for COPD patients: a 6-month randomised, controlled study.

    PubMed

    Eaton, T; Fergusson, W; Kolbe, J; Lewis, C A; West, T

    2006-04-01

    Short-burst oxygen therapy (SBOT) remains widely advocated for patients with chronic obstructive pulmonary disease (COPD), despite a lack of supporting evidence. The aim of this randomised, double-blind, placebo-controlled, parallel group study was to determine whether SBOT improves health-related quality of life (HRQL) or reduces acute healthcare utilisation in patients discharged following an acute exacerbation of COPD. Consecutive patients were screened; 78 of 331 were eligible for randomisation to cylinder oxygen, cylinder air or usual care following discharge. Patients were elderly with high acute healthcare utilisation, forced expiratory volume in one second of <1 L and had dyspnoea limiting daily activity but were not hypoxaemic at rest. Over the 6-month study period, there were no significant differences between patient groups in HRQL (Chronic Respiratory Questionnaire (CRQ), 36-item Short-Form Health Survey, Hospital Anxiety and Depression Scale) except for CRQ emotion domain. There were no significant differences in acute healthcare utilisation. Time to readmission was greatest in the usual care group. Cylinder use was high initially, but rapidly fell to very low levels within weeks in both cylinder oxygen and air groups. In conclusion, the availability of short-burst oxygen therapy for chronic obstructive pulmonary disease patients discharged from hospital following an acute exacerbation did not improve health-related quality of life or reduce acute healthcare utilisation. These results provide no support for the widespread use of short-burst oxygen therapy.

  6. Live lecture versus video podcast in undergraduate medical education: A randomised controlled trial

    PubMed Central

    2010-01-01

    Background Information technology is finding an increasing role in the training of medical students. We compared information recall and student experience and preference after live lectures and video podcasts in undergraduate medical education. Methods We performed a crossover randomised controlled trial. 100 students were randomised to live lecture or video podcast for one clinical topic. Live lectures were given by the same instructor as the narrator of the video podcasts. The video podcasts comprised Powerpoint™ slides narrated using the same script as the lecture. They were then switched to the other group for a second clinical topic. Knowledge was assessed using multiple choice questions and qualitative information was collected using a questionnaire. Results No significant difference was found on multiple choice questioning immediately after the session. The subjects enjoyed the convenience of the video podcast and the ability to stop, review and repeat it, but found it less engaging as a teaching method. They expressed a clear preference for the live lecture format. Conclusions We suggest that video podcasts are not ready to replace traditional teaching methods, but may have an important role in reinforcing learning and aiding revision. PMID:20932302

  7. Do brief online planning interventions increase physical activity amongst university students? A randomised controlled trial.

    PubMed

    Skår, Silje; Sniehotta, Falko F; Molloy, Gerard J; Prestwich, Andrew; Araújo-Soares, Vera

    2011-04-01

    Brief planning interventions, usually delivered within paper and pencil questionnaires, have been found to be effective in changing health behaviours. Using a double-blind randomised controlled trial, this study examined the efficacy of two types of planning interventions (action plans and coping plans) in increasing physical activity levels when they are delivered via the internet. Following the completion of self-reported physical activity (primary outcome) and theory of planned behaviour (TPB) measures at baseline, students (N = 1273) were randomised into one of four conditions on the basis of a 2 (received instructions to form action plans or not) × 2 (received instructions to form coping plans or not) factorial design. Physical activity (primary outcome) and TPB measures were completed again at two-month follow-up. An objective measure (attendance at the university's sports facilities) was employed 6 weeks after a follow-up for a duration of 13 weeks (secondary outcome). The interventions did not change self-reported physical activity, attendance at campus sports facilities or TPB measures. This might be due to low adherence to the intervention protocol (ranging from 58.8 to 76.7%). The results of this study suggest that the planning interventions under investigation are ineffective in changing behaviour when delivered online to a sample of participants unaware of the allocation to different conditions. Possible moderators of the effectiveness of planning interventions in changing health behaviours are discussed.

  8. Replicability of sight word training and phonics training in poor readers: a randomised controlled trial

    PubMed Central

    Kohnen, S; Jones, K; Eve, P; Banales, E; Larsen, L; Castles, A

    2015-01-01

    Given the importance of effective treatments for children with reading impairment, paired with growing concern about the lack of scientific replication in psychological science, the aim of this study was to replicate a quasi-randomised trial of sight word and phonics training using a randomised controlled trial (RCT) design. One group of poor readers (N = 41) did 8 weeks of phonics training (i.e., phonological decoding) and then 8 weeks of sight word training (i.e., whole-word recognition). A second group did the reverse order of training. Sight word and phonics training each had a large and significant valid treatment effect on trained irregular words and word reading fluency. In addition, combined sight word and phonics training had a moderate and significant valid treatment effect on nonword reading accuracy and fluency. These findings demonstrate the reliability of both phonics and sight word training in treating poor readers in an era where the importance of scientific reliability is under close scrutiny. PMID:26019992

  9. Effectiveness of group body psychotherapy for negative symptoms of schizophrenia: multicentre randomised controlled trial†

    PubMed Central

    Priebe, S.; Savill, M.; Wykes, T.; Bentall, R. P.; Reininghaus, U.; Lauber, C.; Bremner, S.; Eldridge, S.; Röhricht, F.

    2016-01-01

    Background Negative symptoms of schizophrenia have a severe impact on functional outcomes and treatment options are limited. Arts therapies are currently recommended but more evidence is required. Aims To assess body psychotherapy as a treatment for negative symptoms compared with an active control (trial registration: ISRCTN84216587). Method Schizophrenia out-patients were randomised into a 20-session body psychotherapy or Pilates group. The primary outcome was negative symptoms at end of treatment. Secondary outcomes included psychopathology, functional, social and treatment satisfaction outcomes at treatment end and 6-months later. Results In total, 275 participants were randomised. The adjusted difference in negative symptoms was 0.03 (95% CI −1.11 to 1.17), indicating no benefit from body psychotherapy. Small improvements in expressive deficits and movement disorder symptoms were detected in favour of body psychotherapy. No other outcomes were significantly different. Conclusions Body psychotherapy does not have a clinically relevant beneficial effect in the treatment of patients with negative symptoms of schizophrenia. PMID:27151073

  10. Advice to eat fish and mood: a randomised controlled trial in men with angina.

    PubMed

    Ness, Andrew R; Gallacher, John E J; Bennett, Paul D; Gunnell, David J; Rogers, Peter J; Kessler, David; Burr, Michael L

    2003-02-01

    People with high intake of fish have lower reported rates of depression and a small trial in psychiatric patients suggested that fish oil supplements reduced episodes of depression and mania. As part of a factorial trial of interventions to reduce mortality in angina 452 men were randomised to advice to eat more fatty fish or no fish advice. Maxepa fish oil capsules were supplied to men who found the fish unpalatable. Fish intake and mood were assessed at baseline and six months. Most men (83%) had mood assessed using the Derogatis Stress Profile at baseline and follow-up. Self reported intake of fish was higher in the fish advice group at six months. There was, however, no difference in depression or anxiety in those allocated to receive fish advice. After controlling for baseline mood, the difference in depression score between those randomised to fish advice and those not was 1.29 (95% CI -0.29 to 2.88) and the difference in anxiety was 0.82 (95% CI -0.57 to 2.22) with positive differences indicating more depression or anxiety in those allocated to the fish arm. This trial provides no evidence that increased fatty fish intake in people without depressive symptoms has any substantial effect on mood.

  11. Comparison of effects of amphotericin B deoxycholate infused over 4 or 24 hours: randomised controlled trial

    PubMed Central

    Eriksson, Urs; Seifert, Burkhard; Schaffner, Andreas

    2001-01-01

    Objective To test the hypothesis that amphotericin B deoxycholate is less toxic when given by continuous infusion than by conventional rapid infusion. Design Randomised, controlled, non-blinded, single centre study. Setting University hospital providing tertiary clinical care. Patients 80 mostly neutropenic patients with refractory fever and suspected or proved invasive fungal infections. Intervention Patients were randomised to receive 0.97 mg/kg amphotericin B by continuous infusion over 24 hours or 0.95 mg/kg by rapid infusion over four hours. Main outcome measures Patients were evaluated for side effects related to infusion, nephrotoxicity, and mortality up to three months after treatment. Analysis was on an intention to treat basis. Results Patients in the continuous infusion group had fewer side effects and significantly reduced nephrotoxicity than those in the rapid infusion group. Overall mortality was higher during treatment and after three months' follow up in the rapid infusion than in the continuous infusion group. Conclusion Continuous infusions of amphotericin B reduce nephrotoxicity and side effects related to infusion without increasing mortality. PMID:11238151

  12. Randomised controlled trial of plasma protein fraction versus dopamine in hypotensive very low birthweight infants.

    PubMed Central

    Gill, A B; Weindling, A M

    1993-01-01

    Around 20% of very low birthweight infants admitted to a neonatal intensive care unit become hypotensive within 24 hours of their admission. Standard treatment is either expansion of the circulating volume by the infusion of plasma protein fraction or by using dopamine to improve cardiac function. The purpose of this study was to investigate by a randomised controlled trial which was the most appropriate treatment. Thirty nine infants were randomised to receive either plasma protein fraction or dopamine as first line treatment if they became hypotensive within 24 hours of admission to the neonatal intensive care unit. Seventeen of 19 (89%) infants responded to dopamine, whereas only 9/20 (45%) responded to plasma protein fraction. The median dose of dopamine needed to increase the blood pressure to at least the 10th centile was 7.5 micrograms/kg/min and was infused for a median duration of 18 hours. These observations suggest that dopamine should be used earlier in the treatment of these infants than has previously been recommended. PMID:8215566

  13. School-based intervention for the prevention of HPV among adolescents: a cluster randomised controlled study

    PubMed Central

    Grandahl, Maria; Rosenblad, Andreas; Stenhammar, Christina; Tydén, Tanja; Westerling, Ragnar; Larsson, Margareta; Oscarsson, Marie; Andrae, Bengt; Dalianis, Tina; Nevéus, Tryggve

    2016-01-01

    Objective To improve primary prevention of human papillomavirus (HPV) infection by promoting vaccination and increased condom use among upper secondary school students. Design Cluster randomised controlled trial. Setting 18 upper secondary schools in Sweden. Participants Schools were first randomised to the intervention or the control group, after which individual classes were randomised so as to be included or not. Of the 832 students aged 16 years invited to participate during the regular individual health interview with the school nurse, 751 (90.2%) agreed to participate and 741 (89.1%) students completed the study. Interventions The intervention was based on the Health Belief Model (HBM). According to HBM, a person's health behaviour can be explained by individual beliefs regarding health actions. School nurses delivered 30 min face-to-face structured information about HPV, including cancer risks and HPV prevention, by propagating condom use and HPV vaccination. Students in the intervention and the control groups completed questionnaires at baseline and after 3 months. Main outcome measures Intention to use condom with a new partner and beliefs about primary prevention of HPV, and also specifically vaccination status and increased condom use. Results All statistical analyses were performed at the individual level. The intervention had a significant effect on the intention to use condom (p=0.004). There was also a significant effect on HBM total score (p=0.003), with a 2.559 points higher score for the intervention group compared to the controls. The influence on the HBM parameters susceptibility and severity was also significant (p<0.001 for both variables). The intervention also influenced behaviour: girls in the intervention group chose to have themselves vaccinated to a significantly higher degree than the controls (p=0.02). No harms were reported. Conclusions The school-based intervention had favourable effects on the beliefs about primary prevention

  14. Robust Nonlinear Feedback Control of Aircraft Propulsion Systems

    NASA Technical Reports Server (NTRS)

    Garrard, William L.; Balas, Gary J.; Litt, Jonathan (Technical Monitor)

    2001-01-01

    This is the final report on the research performed under NASA Glen grant NASA/NAG-3-1975 concerning feedback control of the Pratt & Whitney (PW) STF 952, a twin spool, mixed flow, after burning turbofan engine. The research focussed on the design of linear and gain-scheduled, multivariable inner-loop controllers for the PW turbofan engine using H-infinity and linear, parameter-varying (LPV) control techniques. The nonlinear turbofan engine simulation was provided by PW within the NASA Rocket Engine Transient Simulator (ROCETS) simulation software environment. ROCETS was used to generate linearized models of the turbofan engine for control design and analysis as well as the simulation environment to evaluate the performance and robustness of the controllers. Comparison between the H-infinity, and LPV controllers are made with the baseline multivariable controller and developed by Pratt & Whitney engineers included in the ROCETS simulation. Simulation results indicate that H-infinity and LPV techniques effectively achieve desired response characteristics with minimal cross coupling between commanded values and are very robust to unmodeled dynamics and sensor noise.

  15. Pupil Control Behavior, Classroom Robustness, and Self-Control: Public and Military Secondary Schools.

    ERIC Educational Resources Information Center

    Sartori, Mary Ann; Bauske, Terri; Lunenburg, Fred C.

    2000-01-01

    Investigated students' perceptions of teachers pupil-control behavior, classroom robustness, and student self-control, highlighting possible differences between public and military secondary schools. Humanistic approaches had more positive, interrelated effects among these variables. Military (custodial) classrooms were perceived as less robust,…

  16. Robust nonlinear variable selective control for networked systems

    NASA Astrophysics Data System (ADS)

    Rahmani, Behrooz

    2016-10-01

    This paper is concerned with the networked control of a class of uncertain nonlinear systems. In this way, Takagi-Sugeno (T-S) fuzzy modelling is used to extend the previously proposed variable selective control (VSC) methodology to nonlinear systems. This extension is based upon the decomposition of the nonlinear system to a set of fuzzy-blended locally linearised subsystems and further application of the VSC methodology to each subsystem. To increase the applicability of the T-S approach for uncertain nonlinear networked control systems, this study considers the asynchronous premise variables in the plant and the controller, and then introduces a robust stability analysis and control synthesis. The resulting optimal switching-fuzzy controller provides a minimum guaranteed cost on an H2 performance index. Simulation studies on three nonlinear benchmark problems demonstrate the effectiveness of the proposed method.

  17. Randomised control trial of pH buffered lignocaine with adrenaline in outpatient operations.

    PubMed

    Masters, J E

    1998-07-01

    Bicarbonate buffering of local anaesthetics is known to significantly decrease the pain of their administration and yet few practising surgeons do so. A double-blind randomised cross-over clinical trial was conducted to confirm the practicality and efficacy of bicarbonate buffering of lignocaine with adrenaline in the setting of a busy local anaesthetic operating theatre. 40 patients received either buffered or control local anaesthetic solutions in equivalent sites on opposite sides of the body. The pain of each injection was rated from 0 (no pain) to 10 (extreme pain). The mean pain score for the buffered solution was significantly lower than the control solution (3.06 vs 4.34, P = 0.002). Bicarbonate buffering of lignocaine with adrenaline is effective, inexpensive and simple; its widespread use should be encouraged.

  18. Safe household water treatment and storage using ceramic drip filters: a randomised controlled trial in Bolivia.

    PubMed

    Clasen, T; Brown, J; Suntura, O; Collin, S

    2004-01-01

    A randomised controlled field trial was conducted to evaluate the effectiveness of ceramic drip filters to improve the microbiological quality of drinking water in a low-income community in rural Bolivia. In four rounds of water sampling over five months, 100% of the samples were free of thermotolerant (faecal) coliforms (TTC) compared to an arithmetic mean TTC count of 1517, 406, 167 and 245 among control households which continued to use their customary sources of drinking water. The filter systems produced water that consistently met WHO drinking-water standards despite levels of turbidity that presented a challenge to other low-cost POU treatment methods. The filter systems also demonstrated an ability to maintain the high quality of the treated water against subsequent re-contamination in the home.

  19. A feasibility randomised controlled trial of the DECIDE intervention: dementia carers making informed decisions

    PubMed Central

    Lord, Kathryn; Livingston, Gill

    2017-01-01

    Summary Family carers report high levels of decisional conflict when deciding whether their relative with dementia can continue to be cared for in their own home. We tested, in a feasibility randomised controlled trial, the first decision aid (the DECIDE manual) aiming to reduce such conflict. Twenty family carers received the DECIDE intervention, and 21 received usual treatment. The intervention group had reduced decisional conflict compared with controls (mean difference −11.96, 95% confidence interval −20.10 to −3.83, P=0.005). All carers receiving the intervention completed and valued it, despite some still reporting difficulties with family conflict and problems negotiating services. Declaration of interest None. Copyright and usage © The Royal College of Psychiatrists 2017. This is an open access article distributed under the terms of the Creative Commons Non-Commercial, No Derivatives (CC BY-NC-ND) license. PMID:28243460

  20. Lyapunov function gradient generated robust control in the absence of the nominal stabilizing control

    NASA Technical Reports Server (NTRS)

    Blackwell, C. C.

    1987-01-01

    A relevant facet of the application of Lyapunov gradient-generated robust control to unstable linear autonomous plants is explored. It is demonstrated that if the plant, the output, and the nominal stabilizing control satisfy certain conditions, then the robust component alone stabilizes the nominal plant. An example characterized by two zero eigenvalues and two negative real value poles is presented. These results assure that the robust component will fulfill the role of nominal stabilization successfully so long as the possible magnitude of the robust component can overcome the contribution of the instability to positiveness of the Lyapunov rate.

  1. Early home-supported discharge for patients with stroke in Portugal: a randomised controlled trial

    PubMed Central

    Santana, Silvina; Rente, José; Neves, Conceição; Redondo, Patrícia; Szczygiel, Nina; Larsen, Torben; Jepsen, Birgitte; Langhorne, Peter

    2016-01-01

    Objective: To evaluate an early home-supported discharge service for stroke patients. Design: We carried out a prospective, randomised, open-label, blinded-endpoint trial (allocation ratio of 1:1) with patients assigned to either an early home-supported discharge service or usual care. Setting: The study was undertaken in Aveiro, Portugal, between April 2009 and April 2013. Subjects: We included stroke patients aged 25–85 years admitted to the stroke unit with an initial Functional Independence Measure of up to 100, who gave informed consent. Interventions: Patients in the early home-supported discharge group began their rehabilitation intervention in the stroke unit and the early home-supported discharge team worked with them at home for a maximum of one month. Patients in the control group received usual services. Main measures: The primary outcome measure was the Functional Independence Measure at six months after stroke. Results: We randomised 190 patients of whom 34 were lost to follow-up. There were no significant differences (p > 0.5) in the average scores of Functional Independence Measure between the early home-supported discharge (69 ±22; mean ±SD) and the control groups (71 ±17) measured at baseline; and between the early home-supported discharge (107 ±20) and the control groups (107 ±25) measured at six months. The number of individuals with a low Functional Independence Measure score (<60) in the early home-supported discharge group compared with the control group was higher at admission (34/95 vs. 26/95) and lower at follow-up (2/74 vs. 5/78). Conclusions: It was feasible to implement early home-supported discharge procedures in a Southern European setting, but we have not shown convincing differences in disability at six months. PMID:26837431

  2. Arm exercise training in chronic obstructive pulmonary disease: a randomised controlled trial.

    PubMed

    McKeough, Zoe J; Bye, Peter T P; Alison, Jennifer A

    2012-08-01

    The aim of this study was to compare the effects of arm endurance training, arm strength training, a combination of arm endurance and strength training, and no arm training on endurance arm exercise capacity. A randomised controlled trial was undertaken with chronic obstructive pulmonary disease subjects randomised into one of four groups to complete 8 weeks of training: (a) arm endurance training (endurance group) consisting of supported and unsupported arm exercises, (b) arm strength training (strength group) using weight machines, (c) a combination of arm endurance and arm strength training (combined group), or (d) no arm training (control group). The primary outcome measurement was endurance arm exercise capacity measured by an endurance arm crank test. Secondary outcomes included functional arm exercise capacity measured by the incremental unsupported arm exercise test and health-related quality of life. A total of 52 subjects were recruited and 38 (73%) completed the study. When comparing the arm endurance group to the control group, there was a significant increase in endurance time of 6 min (95% CI 2-10, p < 0.01) following the interventions. When comparing the combined group to each of the control, endurance and strength groups, there was a significantly greater reduction in dyspnoea and rate of perceived exertion at the end of the functional arm exercise test for the combined group following the interventions. The mode of training to be favoured to increase endurance arm exercise capacity is arm endurance training. However, combined arm endurance and strength training may also be very useful to reduce the symptoms during everyday arm tasks.

  3. Parametric robust control and system identification: Unified approach

    NASA Technical Reports Server (NTRS)

    Keel, Leehyun

    1994-01-01

    Despite significant advancement in the area of robust parametric control, the problem of synthesizing such a controller is still a wide open problem. Thus, we attempt to give a solution to this important problem. Our approach captures the parametric uncertainty as an H(sub infinity) unstructured uncertainty so that H(sub infinity) synthesis techniques are applicable. Although the techniques cannot cope with the exact parametric uncertainty, they give a reasonable guideline to model the unstructured uncertainty that contains the parametric uncertainty. An additional loop shaping technique is also introduced to relax its conservatism.

  4. A Randomised Controlled Trial Using Mobile Advertising to Promote Safer Sex and Sun Safety to Young People

    ERIC Educational Resources Information Center

    Gold, J.; Aitken, C. K.; Dixon, H. G.; Lim, M. S. C.; Gouillou, M.; Spelman, T.; Wakefield, M.; Hellard, M. E.

    2011-01-01

    Mobile phone text messages (SMS) are a promising method of health promotion, but a simple and low cost way to obtain phone numbers is required to reach a wide population. We conducted a randomised controlled trial with simultaneous brief interventions to (i) evaluate effectiveness of messages related to safer sex and sun safety and (ii) pilot the…

  5. Can exercise improve self esteem in children and young people? A systematic review of randomised controlled trials

    PubMed Central

    Ekeland, E; Heian, F; Hagen, K; Coren, E

    2005-01-01

    Twenty three randomised controlled trials were analysed. A synthesis of several small, low quality trials indicates that exercise may have short term beneficial effects on self esteem in children and adolescents. However, high quality research on defined populations with adequate follow up is needed. PMID:16244186

  6. Are Prenatal Ultrasound Scans Associated with the Autism Phenotype? Follow-Up of a Randomised Controlled Trial

    ERIC Educational Resources Information Center

    Stoch, Yonit K.; Williams, Cori J.; Granich, Joanna; Hunt, Anna M.; Landau, Lou I.; Newnham, John P.; Whitehouse, Andrew J. O.

    2012-01-01

    An existing randomised controlled trial was used to investigate whether multiple ultrasound scans may be associated with the autism phenotype. From 2,834 single pregnancies, 1,415 were selected at random to receive ultrasound imaging and continuous wave Doppler flow studies at five points throughout pregnancy (Intensive) and 1,419 to receive a…

  7. Effect of a Universal Anxiety Prevention Programme (FRIENDS) on Children's Academic Performance: Results from a Randomised Controlled Trial

    ERIC Educational Resources Information Center

    Skryabina, Elena; Taylor, Gordon; Stallard, Paul

    2016-01-01

    Background: Evaluations of school-based anxiety prevention programmes have reported improvements in psychological functioning although little is known about their effect upon educational outcomes. Methods: One thousand three hundred and sixty-two children from 40 primary schools in England took part in the randomised controlled trial, Preventing…

  8. A Randomised Controlled Trial to Determine the Effectiveness of an Early Psychological Intervention with Children Involved in Road Traffic Accidents

    ERIC Educational Resources Information Center

    Stallard, Paul; Velleman, Richard; Salter, Emma; Howse, Imogen; Yule, William; Taylor, Gordon

    2006-01-01

    Objective: To determine whether an early intervention using a psychological debriefing format is effective in preventing psychological distress in child road traffic accident survivors. Design: Randomised controlled trial. Setting: Accident and Emergency Department, Royal United Hospital, Bath. Subjects: 158 children aged 7-18. Follow-up…

  9. "Every Child Counts": Testing Policy Effectiveness Using a Randomised Controlled Trial, Designed, Conducted and Reported to CONSORT Standards

    ERIC Educational Resources Information Center

    Torgerson, Carole; Wiggins, Andy; Torgerson, David; Ainsworth, Hannah; Hewitt, Catherine

    2013-01-01

    We report a randomised controlled trial evaluation of an intensive one-to-one numeracy programme--"Numbers Count"--which formed part of the previous government's numeracy policy intervention--"Every Child Counts." We rigorously designed and conducted the trial to CONSORT guidelines. We used a pragmatic waiting list design to…

  10. Linear, multivariable robust control with a mu perspective

    NASA Technical Reports Server (NTRS)

    Packard, Andy; Doyle, John; Balas, Gary

    1993-01-01

    The structured singular value is a linear algebra tool developed to study a particular class of matrix perturbation problems arising in robust feedback control of multivariable systems. These perturbations are called linear fractional, and are a natural way to model many types of uncertainty in linear systems, including state-space parameter uncertainty, multiplicative and additive unmodeled dynamics uncertainty, and coprime factor and gap metric uncertainty. The structured singular value theory provides a natural extension of classical SISO robustness measures and concepts to MIMO systems. The structured singular value analysis, coupled with approximate synthesis methods, make it possible to study the tradeoff between performance and uncertainty that occurs in all feedback systems. In MIMO systems, the complexity of the spatial interactions in the loop gains make it difficult to heuristically quantify the tradeoffs that must occur. This paper examines the role played by the structured singular value (and its computable bounds) in answering these questions, as well as its role in the general robust, multivariable control analysis and design problem.

  11. Lay support for pregnant women with social risk: a randomised controlled trial

    PubMed Central

    Kenyon, Sara; Jolly, Kate; Hemming, Karla; Hope, Lucy; Blissett, Jackie; Dann, Sophie-Anna; Lilford, Richard; MacArthur, Christine

    2016-01-01

    Objectives We sought evidence of effectiveness of lay support to improve maternal and child outcomes in disadvantaged families. Design Prospective, pragmatic, individually randomised controlled trial. Setting 3 Maternity Trusts in West Midlands, UK. Participants Following routine midwife systematic assessment of social risk factors, 1324 nulliparous women were assigned, using telephone randomisation, to standard maternity care, or addition of referral to a Pregnancy Outreach Worker (POW) service. Those under 16 years and teenagers recruited to the Family Nurse Partnership trial were excluded. Interventions POWs were trained to provide individual support and case management for the women including home visiting from randomisation to 6 weeks after birth. Standard maternity care (control) included provision for referring women with social risk factors to specialist midwifery services, available to both arms. Main outcome measures Primary outcomes were antenatal visits attended and Edinburgh Postnatal Depression Scale (EPDS) 8–12 weeks postpartum. Prespecified, powered, subgroup comparison was among women with 2 or more social risks. Secondary outcomes included maternal and neonatal birth outcomes; maternal self-efficacy, and mother-to-infant bonding at 8–12 weeks; child development assessment at 6 weeks, breastfeeding at 6 weeks, and immunisation uptake at 4 months, all collected from routine child health systems. Results Antenatal attendances were high in the standard care control and did not increase further with addition of the POW intervention (10.1 vs 10.1 (mean difference; MD) −0.00, 95% CI (95% CI −0.37 to 0.37)). In the powered subgroup of women with 2 or more social risk factors, mean EPDS (MD −0.79 (95% CI −1.56 to −0.02) was significantly better, although for all women recruited, no significant differences were seen (MD −0.59 (95% CI −1.24 to 0.06). Mother-to-infant bonding was significantly better in the intervention group

  12. A randomised controlled trial of post-operative rehabilitation after surgical decompression of the lumbar spine

    PubMed Central

    Denzler, Raymond; Dvorak, Jiri; Müntener, Markus; Grob, Dieter

    2007-01-01

    Spinal decompression is the most common type of spinal surgery carried out in the older patient, and is being performed with increasing frequency. Physiotherapy (rehabilitation) is often prescribed after surgery, although its benefits compared with no formal rehabilitation have yet to be demonstrated in randomised control trials. The aim of this randomised controlled trial was to examine the effects on outcome up to 2 years after spinal decompression surgery of two types of postoperative physiotherapy compared with no postoperative therapy (self-management). Hundred and fifty-nine patients (100 men, 59 women; 65 ± 11 years) undergoing decompression surgery for spinal stenosis/herniated disc were randomised to one of the following programmes beginning 2 months post-op: recommended to “keep active” (CONTROL; n = 54); physiotherapy, spine stabilisation exercises (PT-StabEx; n = 56); physiotherapy, mixed techniques (PT-Mixed; n = 49). Both PT programmes involved 2 × 30 min sessions/week for up to 12 weeks, with home exercises. Pain intensity (0–10 graphic rating scale, for back and leg pain separately) and self-rated disability (Roland Morris) were assessed before surgery, before and after the rehabilitation phase (approx. 2 and 5 months post-op), and at 12 and 24 months after the operation. ‘Intention to treat’ analyses were used. At 24 months, 151 patients returned questionnaires (effective return rate, excluding 4 deaths, 97%). Significant reductions in leg and back pain and self-rated disability were recorded after surgery (P < 0.05). Pain showed no further changes in any group up to 24 months later, whereas disability declined further during the “rehabilitation” phase (P < 0.05) then stabilised, but with no significant group differences. 12 weeks of post-operative physiotherapy did not influence the course of change in pain or disability up to 24 months after decompression surgery. Advising patients to keep active by

  13. A robust decentralized load frequency controller for interconnected power systems.

    PubMed

    Dong, Lili; Zhang, Yao; Gao, Zhiqiang

    2012-05-01

    A novel design of a robust decentralized load frequency control (LFC) algorithm is proposed for an inter-connected three-area power system, for the purpose of regulating area control error (ACE) in the presence of system uncertainties and external disturbances. The design is based on the concept of active disturbance rejection control (ADRC). Estimating and mitigating the total effect of various uncertainties in real time, ADRC is particularly effective against a wide range of parameter variations, model uncertainties, and large disturbances. Furthermore, with only two tuning parameters, the controller provides a simple and easy-to-use solution to complex engineering problems in practice. Here, an ADRC-based LFC solution is developed for systems with turbines of various types, such as non-reheat, reheat, and hydraulic. The simulation results verified the effectiveness of the ADRC, in comparison with an existing PI-type controller tuned via genetic algorithm linear matrix inequalities (GALMIs). The comparison results show the superiority of the proposed solution. Moreover, the stability and robustness of the closed-loop system is studied using frequency-domain analysis.

  14. Patient safety in elderly hip fracture patients: design of a randomised controlled trial

    PubMed Central

    2011-01-01

    Background The clinical environment in which health care providers have to work everyday is highly complex; this increases the risk for the occurrence of unintended events. The aim of this randomised controlled trial is to improve patient safety for a vulnerable group of patients that have to go through a complex care chain, namely elderly hip fracture patients. Methods/design A randomised controlled trial that consists of three interventions; these will be implemented in three surgical wards in Dutch hospitals. One surgical ward in another hospital will be the control group. The first intervention is aimed at improving communication between care providers using the SBAR communication tool. The second intervention is directed at stimulating the role of the patient within the care process with a patient safety card. The third intervention consists of a leaflet for patients with information on the most common complications for the period after discharge. The primary outcome measures in this study are the incidence of complications and adverse events, mortality rate within six months after discharge and functional mobility six months after discharge. Secondary outcome measures are length of hospital stay, quality and completeness of information transfer and patient satisfaction with the instruments. Discussion The results will give insight into the nature and scale of complications and adverse events that occur in elderly hip fracture patients. Also, the implementation of three interventions aimed at improving the communication and information transfer provides valuable possibilities for improving patient safety in this increasing patient group. This study combines the use of three interventions, which is an innovative aspect of the study. Trial registration The Netherlands National Trial Register NTR1562 PMID:21418630

  15. Parenting for Autism, Language, And Communication Evaluation Study (PALACES): protocol for a pilot randomised controlled trial

    PubMed Central

    Williams, Margiad Elen; Hastings, Richard; Charles, Joanna Mary; Evans, Sue; Hutchings, Judy

    2017-01-01

    Introduction Children with autistic spectrum disorder (ASD) often have associated behavioural difficulties that can present a challenge for parents and parenting. There are several effective social learning theory-based parenting programmes for dealing with behavioural difficulties, including the Incredible Years (IY) parent programmes. However, these programmes typically do not specifically target parents of children with ASD. Recently, a new addition to the IY suite of programmes known as the IY Autistic Spectrum and Language Delays (IY-ASLD) parent programme was developed. The main aims of the present study are to examine the feasibility of delivering this programme within child health services and to provide initial evidence for effectiveness and economic costs. Methods and analysis The Parenting for Autism, Language, And Communication Evaluation Study (PALACES) trial is a pragmatic, multicentre, pilot randomised controlled trial comparing the IY-ASLD programme with a wait-list control condition. 72 parents of children with ASD (aged 3–8 years) will be randomly allocated to either the intervention or control condition. Data will be collected prior to randomisation and 6 months postrandomisation for all families. Families in the intervention condition only will also be followed up at 12 and 18 months postrandomisation. This study will provide initial evidence of effectiveness for the newly developed IY-ASLD parenting programme. It will also add to the limited economic evidence for an intervention targeting parents of children with ASD and provide longer term data, an important component for evaluations of parenting programmes. Ethics and dissemination Approval for the study was granted by the Research Ethics Committee at the School of Psychology, Bangor University (reference number: 2016–15768) and the North Wales Research Ethics Committee, UK (reference number: 16/WA/0224). The findings will be disseminated through research conferences and peer

  16. Recruitment issues when primary care population clusters are used in randomised controlled clinical trials: climbing mountains or pushing boulders uphill?

    PubMed

    Hoddinott, Pat; Britten, Jane; Harrild, Kirsten; Godden, David J

    2007-05-01

    Cluster randomised controlled trials for health promotion, education, public health or organisational change interventions are becoming increasingly common to inform evidence-based policy. However, there is little published methodological evidence on recruitment strategies for primary care population clusters. In this paper, we discuss how choosing which population cluster to randomise can impact on the practicalities of recruitment in primary care. We describe strategies developed through our experiences of recruiting primary care organisations to participate in a national randomised controlled trial of a policy to provide community breastfeeding groups for pregnant and breastfeeding mothers, the BIG (Breastfeeding in Groups) trial. We propose an iterative qualitative approach to recruitment; collecting data generated through the recruitment process, identifying themes and using the constant comparative method of analysis. This can assist in developing successful recruitment strategies and contrasts with the standardised approach commonly used when recruiting individuals to participate in randomised controlled trials. Recruiting primary care population clusters to participate in trials is currently an uphill battle in Britain. It is a complex process, which can benefit from applying qualitative methods to inform trial design and recruitment strategy. Recruitment could be facilitated if health service managers were committed to supporting peer reviewed, funded and ethics committee approved research at national level.

  17. A new robust adaptive controller for vibration control of active engine mount subjected to large uncertainties

    NASA Astrophysics Data System (ADS)

    Fakhari, Vahid; Choi, Seung-Bok; Cho, Chang-Hyun

    2015-04-01

    This work presents a new robust model reference adaptive control (MRAC) for vibration control caused from vehicle engine using an electromagnetic type of active engine mount. Vibration isolation performances of the active mount associated with the robust controller are evaluated in the presence of large uncertainties. As a first step, an active mount with linear solenoid actuator is prepared and its dynamic model is identified via experimental test. Subsequently, a new robust MRAC based on the gradient method with σ-modification is designed by selecting a proper reference model. In designing the robust adaptive control, structured (parametric) uncertainties in the stiffness of the passive part of the mount and in damping ratio of the active part of the mount are considered to investigate the robustness of the proposed controller. Experimental and simulation results are presented to evaluate performance focusing on the robustness behavior of the controller in the face of large uncertainties. The obtained results show that the proposed controller can sufficiently provide the robust vibration control performance even in the presence of large uncertainties showing an effective vibration isolation.

  18. Defining the fracture population in a pragmatic multicentre randomised controlled trial

    PubMed Central

    Handoll, H. H. G.; Brealey, S. D.; Jefferson, L.; Keding, A.; Brooksbank, A. J.; Johnstone, A. J.; Candal-Couto, J. J.

    2016-01-01

    Objectives Accurate characterisation of fractures is essential in fracture management trials. However, this is often hampered by poor inter-observer agreement. This article describes the practicalities of defining the fracture population, based on the Neer classification, within a pragmatic multicentre randomised controlled trial in which surgical treatment was compared with non-surgical treatment in adults with displaced fractures of the proximal humerus involving the surgical neck. Methods The trial manual illustrated the Neer classification of proximal humeral fractures. However, in addition to surgical neck displacement, surgeons assessing patient eligibility reported on whether either or both of the tuberosities were involved. Anonymised electronic versions of baseline radiographs were sought for all 250 trial participants. A protocol, data collection tool and training presentation were developed and tested in a pilot study. These were then used in a formal assessment and classification of the trial fractures by two independent senior orthopaedic shoulder trauma surgeons. Results Two or more baseline radiographic views were obtained for each participant. The independent raters confirmed that all fractures would have been considered for surgery in contemporaneous practice. A full description of the fracture population based on the Neer classification was obtained. The agreement between the categorisation at baseline (tuberosity involvement) and Neer classification as assessed by the two raters was only fair (kappa 0.29). However, this disparity did not appear to affect trial findings, specifically in terms of influencing the effect of treatment on the primary outcome of the trial. Conclusions A key reporting requirement, namely the description of the fracture population, was achieved within the context of a pragmatic multicentre randomised clinical trial. This article provides important guidance for researchers designing similar trials on fracture management

  19. Smoking cessation at the workplace. Results of a randomised controlled intervention study

    PubMed Central

    Lang, T; Nicaud, V; Slama, K; Hirsch, A; Imbernon, E; Goldberg, M; Calvel, L; Desobry, P; Favre-Trosson, J; Lhopital, C; Mathevon, P; Miara, D; Miliani, A; Panthier, F; Pons, G; Roitg, C; Thoores, M; the, w

    2000-01-01

    OBJECTIVES—To compare the effects of a worksite intervention by the occupational physician offering simple advice of smoking cessation with a more active strategy of advice including a "quit date" and extra support.
POPULATION—Employees of an electrical and gas company seen at the annual visit by their occupational physicians.
CRITERIA END POINTS—Smoking point prevalence defined as the percentage of smokers who were non-smokers at one year. Secondary criteria were the percentage of smokers who stopped smoking for more than six months and the difference in prevalence of smoking in both groups.
METHODS—Randomised controlled trial. The unit of randomisation was the work site physician and a random sample of the employees of whom he or she was in charge. The length of the follow up was one year. Each of 30 work site physicians included in the study 100 to 150 employees.
RESULTS—Among 504 subjects classified as smokers at baseline receiving simple advice (group A) and 591 the more active programme (group B), 68 (13.5%) in group A and 109 (18.4%) were non-smokers one year later (p=0.03; p=0.01 taking the occupational physician as the statistical unit and using a non-parametric test). Twenty three subjects (4.6%) in group A and 36 (6.1%) in group B (p=0.26) declared abstinence of six months or more. Among non-smokers at baseline, 3.4% in both groups were smokers after one year follow up. The prevalence of smokers did not differ significantly at baseline (32.9% and 32.4%, p=0.75). After the intervention the prevalence of smoking was 30.8% in group A and 28.7% in group B (p=0.19). An increase of the mean symptoms score for depression in those who quit was observed during this period.
CONCLUSIONS—A simple cessation intervention strategy during a mandatory annual examination, targeting a population of smokers independently of their motivation to stop smoking or their health status, showed a 36% relative increase of the proportion of smokers who

  20. Telemonitoring based service redesign for the management of uncontrolled hypertension: multicentre randomised controlled trial

    PubMed Central

    Hanley, Janet; Wild, Sarah; Pagliari, Claudia; Paterson, Mary; Lewis, Steff; Sheikh, Aziz; Krishan, Ashma; Stoddart, Andrew; Padfield, Paul

    2013-01-01

    Objective To determine if an intervention consisting of telemonitoring and supervision by usual primary care clinicians of home self measured blood pressure and optional patient decision support leads to clinically important reductions in daytime systolic and diastolic ambulatory blood pressure in patients with uncontrolled blood pressure. Design Multicentre randomised controlled trial. Setting 20 primary care practices in south east Scotland. Participants 401 people aged 29-95 years with uncontrolled blood pressure (mean daytime ambulatory measurement ≥135/85 mm Hg but ≤210/135 mm Hg). Intervention Self measurement and transmission of blood pressure readings to a secure website for review by the attending nurse or doctor and participant, with optional automated patient decision support by text or email for six months. Main outcome measures Blinded assessment of mean daytime systolic ambulatory blood pressure six months after randomisation. Results 200 participants were randomised to the intervention and 201 to usual care; primary outcome data were available for 90% of participants (182 and 177, respectively). The mean difference in daytime systolic ambulatory blood pressure adjusted for baseline and minimisation factors between intervention and usual care was 4.3 mm Hg (95% confidence interval 2.0 to 6.5; P=0.0002) and for daytime diastolic ambulatory blood pressure was 2.3 mm Hg (0.9 to 3.6; P=0.001), with higher values in the usual care group. The intervention was associated with a mean increase of one general practitioner (95% confidence interval 0.5 to 1.6; P=0.0002) and 0.6 (0.1 to 1.0; P=0.01) practice nurse consultations during the course of the study. Conclusions Supported self monitoring by telemonitoring is an effective method for achieving clinically important reductions in blood pressure in patients with uncontrolled hypertension in primary care settings. However, it was associated with increase in use of National Health Service resources. Further

  1. Methods to improve recruitment to randomised controlled trials: Cochrane systematic review and meta-analysis

    PubMed Central

    Treweek, Shaun; Lockhart, Pauline; Pitkethly, Marie; Cook, Jonathan A; Kjeldstrøm, Monica; Johansen, Marit; Taskila, Taina K; Sullivan, Frank M; Wilson, Sue; Jackson, Catherine; Jones, Ritu; Mitchell, Elizabeth D

    2013-01-01

    This review is an abridged version of a Cochrane Review previously published in the Cochrane Database of Systematic Reviews 2010, Issue 4, Art. No.: MR000013 DOI: 10.1002/14651858.MR000013.pub5 (see www.thecochranelibrary.com for information). Cochrane Reviews are regularly updated as new evidence emerges and in response to feedback, and Cochrane Database of Systematic Reviews should be consulted for the most recent version of the review. Objective To identify interventions designed to improve recruitment to randomised controlled trials, and to quantify their effect on trial participation. Design Systematic review. Data sources The Cochrane Methodology Review Group Specialised Register in the Cochrane Library, MEDLINE, EMBASE, ERIC, Science Citation Index, Social Sciences Citation Index, C2-SPECTR, the National Research Register and PubMed. Most searches were undertaken up to 2010; no language restrictions were applied. Study selection Randomised and quasi-randomised controlled trials, including those recruiting to hypothetical studies. Studies on retention strategies, examining ways to increase questionnaire response or evaluating the use of incentives for clinicians were excluded. The study population included any potential trial participant (eg, patient, clinician and member of the public), or individual or group of individuals responsible for trial recruitment (eg, clinicians, researchers and recruitment sites). Two authors independently screened identified studies for eligibility. Results 45 trials with over 43 000 participants were included. Some interventions were effective in increasing recruitment: telephone reminders to non-respondents (risk ratio (RR) 1.66, 95% CI 1.03 to 2.46; two studies, 1058 participants), use of opt-out rather than opt-in procedures for contacting potential participants (RR 1.39, 95% CI 1.06 to 1.84; one study, 152 participants) and open designs where participants know which treatment they are receiving in the trial (RR 1.22, 95

  2. Robust adaptive backstepping control for piezoelectric nano-manipulating systems

    NASA Astrophysics Data System (ADS)

    Zhang, Yangming; Yan, Peng; Zhang, Zhen

    2017-01-01

    In this paper we present a systematic modeling and control approach for nano-manipulations of a two-dimensional PZT (piezoelectric transducer) actuated servo stage. The major control challenges associated with piezoelectric nano-manipulators typically include the nonlinear dynamics of hysteresis, model uncertainties, and various disturbances. The adverse effects of these complications will result in significant performance loss, unless effectively eliminated. The primary goal of the paper is on the ultra high precision control of such systems by handling various model uncertainties and disturbances simultaneously. To this end, a novel robust adaptive backstepping-like control approach is developed such that parametric uncertainties can be estimated adaptively while the nonlinear dynamics and external disturbances are treated as bounded disturbances for robust elimination. Meanwhile, the L2-gain of the closed-loop system is considered, and an H∞ optimization problem is formulated to improve the tracking accuracy. Numerical simulations and real time experiments are finally conducted, which significantly outperform conventional PID methods and achieve around 1% tracking error for circular contouring tasks.

  3. Randomised controlled trials of psychological & pharmacological treatments for body dysmorphic disorder: A systematic review.

    PubMed

    Phillipou, Andrea; Rossell, Susan L; Wilding, Helen E; Castle, David J

    2016-11-30

    Treatment for body dysmorphic disorder (BDD) often involves a combination of psychological and pharmacological interventions. However, only a small number of randomised controlled trials (RCTs) have been undertaken examining the efficacy of different therapeutic interventions. The aim of this study was to systematically review the RCTs involving psychological and pharmacological interventions for the treatment of BDD. The literature was searched to June 2015, and studies were included if they were written in English, empirical research papers published in peer-review journals, specifically assessed BDD patients, and involved a RCT assessing BDD symptoms pre- and post-intervention. Nine studies were identified: six involving psychological and three involving pharmacological interventions. Cognitive behaviour therapy, metacognitive therapy and selective serotonin reuptake inhibitors were identified as treatments with potential benefit. The small number of RCTs and the heterogeneity of findings emphasises the need for more high quality RCTs assessing both psychological and pharmacological interventions for BDD.

  4. Randomised controlled trials of physical activity promotion in free living populations: a review.

    PubMed Central

    Hillsdon, M; Thorogood, M; Anstiss, T; Morris, J

    1995-01-01

    OBJECTIVES--To review evidence on the effectiveness of trials of physical activity promotion in healthy, free living adults. To identify the more effective intervention programmes. METHODS--Computerised databases and references were searched. Experts were contacted and asked for information about existing work. INCLUSION CRITERIA--Randomised controlled trials of healthy, free living adult subjects, where exercise behaviour was the dependent variable were included. CONCLUSIONS--Ten trials were identified. The small number of trials limits the strength of any conclusions and highlights the need for more research. No UK based studies were found. Previously sedentary adults can increase activity levels and sustain them. Promotion of these changes requires personal instruction, continued support, and exercise of moderate intensity which does not depend on attendance at a facility. The exercise should be easily included into an existing lifestyle and should be enjoyable. Walking is the exercise most likely to fulfil these criteria. PMID:7499985

  5. Vouchers versus Lotteries: What works best in promoting Chlamydia screening? A cluster randomised controlled trial

    PubMed Central

    Niza, Claudia; Rudisill, Caroline; Dolan, Paul

    2014-01-01

    In this cluster randomised trial (N=1060), we tested the impact of financial incentives (£5 voucher vs. £200 lottery) framed as a gain or loss to promote Chlamydia screening in students aged 18–24 years, mimicking the standard outreach approach to student in halls of residence. Compared to the control group (1.5%), the lottery increased screening to 2.8% and the voucher increased screening to 22.8%. Incentives framed as gains were marginally more effective (10.5%) that loss-framed incentives (7.1%). This work fundamentally contributes to the literature by testing the predictive validity of Prospect Theory to change health behaviour in the field. PMID:25061507

  6. An overview of randomised controlled trials of adjuvant chemotherapy in head and neck cancer.

    PubMed Central

    Munro, A. J.

    1995-01-01

    Meta-analysis of the published results from 54 randomised controlled trials of adjuvant chemotherapy in head and neck cancer suggests that chemotherapy might increase absolute survival by 6.5% (95% confidence interval 3.1-9.9%). The odds ratio in favour of chemotherapy is 1.37 (95% confidence interval 1.24-1.5). Single-agent chemotherapy given synchronously with radiotherapy increased survival by 12.1% (95% confidence interval 5-19%). The benefit from neoadjuvant chemotherapy was less: a rate difference of 3.7% (95% confidence interval 0.9-6.5%). The results suggest that the investigation of optimal agents and scheduling for synchronous radiotherapy and chemotherapy might still be important in clinical trials in head and neck cancer. PMID:7819055

  7. A randomised controlled trial of acceptance and commitment therapy (ACT) for psychosis: study protocol

    PubMed Central

    2014-01-01

    Background Cognitive behavior therapy for psychosis has been a prominent intervention in the psychological treatment of psychosis. It is, however, a challenging therapy to deliver and, in the context of increasingly rigorous trials, recent reviews have tempered initial enthusiasm about its effectiveness in improving clinical outcomes. Acceptance and commitment therapy shows promise as a briefer, more easily implemented therapy but has not yet been rigorously evaluated in the context of psychosis. The purpose of this trial is to evaluate whether Acceptance and Commitment Therapy could reduce the distress and disability associated with psychotic symptoms in a sample of community-residing patients with chronic medication-resistant symptoms. Methods/Design This is a single (rater)-blind multi-centre randomised controlled trial comparing Acceptance and Commitment Therapy with an active comparison condition, Befriending. Eligible participants have current residual hallucinations or delusions with associated distress or disability which have been present continuously over the past six months despite therapeutic doses of antipsychotic medication. Following baseline assessment, participants are randomly allocated to treatment condition with blinded, post-treatment assessments conducted at the end of treatment and at 6 months follow-up. The primary outcome is overall mental state as measured using the Positive and Negative Syndrome Scale. Secondary outcomes include preoccupation, conviction, distress and disruption to life associated with symptoms as measured by the Psychotic Symptom Rating Scales, as well as social functioning and service utilisation. The main analyses will be by intention-to-treat using mixed-model repeated measures with non-parametric methods employed if required. The model of change underpinning ACT will be tested using mediation analyses. Discussion This protocol describes the first randomised controlled trial of Acceptance and commitment therapy in

  8. The use of glucosamine for chronic low back pain: a systematic review of randomised control trials

    PubMed Central

    Sodha, Reena; Sivanadarajah, Naveethan; Alam, Mahbub

    2013-01-01

    Objectives To ascertain whether the use of oral glucosamine influences symptoms or functional outcomes in patients with chronic low back pain (LBP) thought to be related to spinal osteoarthritis (OA). Design Systematic review of randomised control trials. Searches were performed up to March 2011 on Medline, AMED, CINHAL, Cochrane and EMBASE with subsequent reference screening of retrieved studies. In addition, the grey literature was searched via opensigle. Included studies were required to incorporate at least one of the Cochrane Back Pain Review Group's outcome measures as part of their design. Trials with participants over 18 years with a minimum of 12 weeks of back pain, in combination with radiographic changes of OA in the spine, were included. Studies were rated for risk-of-bias and graded for quality. Results 148 studies were identified after screening and meeting eligibility requirements, and three randomised controlled trials (n=309) were included in the quantitative synthesis. The review found that there was low quality but generally no evidence of an effect from glucosamine on function, with no change in the Roland-Morris Disability Questionnaire score in all studies. Conflicting evidence was demonstrated with pain scores with two studies showing no difference and one study with a high risk-of-bias showing both a statistically and clinically significant improvement from taking glucosamine. Conclusions On the basis of the current research, any clinical benefit of oral glucosamine for patients with chronic LBP and radiographic changes of spinal OA can neither be demonstrated nor excluded based on insufficient data and the low quality of existing studies. PMID:23794557

  9. Improving health-related fitness in adolescents: the CrossFit Teens™ randomised controlled trial.

    PubMed

    Eather, Narelle; Morgan, Philip James; Lubans, David Revalds

    2016-01-01

    The aim of this study was to evaluate the preliminary efficacy and feasibility of the CrossFit Teens™ resistance training programme for improving health-related fitness and resistance training skill competency in adolescents. This assessor-blinded randomised controlled trial was conducted in one secondary school in the Hunter Region, Australia, from July to September 2013. Ninety-six (96) students (age = 15.4 (.5) years, 51.5% female) were randomised into intervention (n = 51) or control (n = 45) conditions for 8-weeks (60 min twice per week). Waist circumference, body mass index (BMI), BMI-Z score (primary outcomes), cardiorespiratory fitness (shuttle run test), muscular fitness (standing jump, push-up, handgrip, curl-up test), flexibility (sit and reach) and resistance training skill competency were measured at baseline and immediate post-intervention. Feasibility measures of recruitment, retention, adherence and satisfaction were assessed. Significant group-by-time intervention effects were found for waist circumference [-3.1 cm, P < 0.001], BMI [-1.38 kg · m(‒)(2), P < 0.001], BMI-Z [-0.5 z-scores, P < 0.001], sit and reach [+3.0 cm, P < 0.001], standing jump [+0.1 m, P = 0.021] and shuttle run [+10.3 laps, P = 0.019]. Retention rate was 82.3%. All programme sessions were delivered and participants' mean satisfaction scores ranged from 4.2 to 4.6 out of 5. The findings demonstrate that CrossFit Teens™ is a feasible and efficacious programme for improving health-related fitness in adolescents.

  10. Defining Feasibility and Pilot Studies in Preparation for Randomised Controlled Trials: Development of a Conceptual Framework

    PubMed Central

    Eldridge, Sandra M.; Lancaster, Gillian A.; Campbell, Michael J.; Thabane, Lehana; Hopewell, Sally; Coleman, Claire L.; Bond, Christine M.

    2016-01-01

    We describe a framework for defining pilot and feasibility studies focusing on studies conducted in preparation for a randomised controlled trial. To develop the framework, we undertook a Delphi survey; ran an open meeting at a trial methodology conference; conducted a review of definitions outside the health research context; consulted experts at an international consensus meeting; and reviewed 27 empirical pilot or feasibility studies. We initially adopted mutually exclusive definitions of pilot and feasibility studies. However, some Delphi survey respondents and the majority of open meeting attendees disagreed with the idea of mutually exclusive definitions. Their viewpoint was supported by definitions outside the health research context, the use of the terms ‘pilot’ and ‘feasibility’ in the literature, and participants at the international consensus meeting. In our framework, pilot studies are a subset of feasibility studies, rather than the two being mutually exclusive. A feasibility study asks whether something can be done, should we proceed with it, and if so, how. A pilot study asks the same questions but also has a specific design feature: in a pilot study a future study, or part of a future study, is conducted on a smaller scale. We suggest that to facilitate their identification, these studies should be clearly identified using the terms ‘feasibility’ or ‘pilot’ as appropriate. This should include feasibility studies that are largely qualitative; we found these difficult to identify in electronic searches because researchers rarely used the term ‘feasibility’ in the title or abstract of such studies. Investigators should also report appropriate objectives and methods related to feasibility; and give clear confirmation that their study is in preparation for a future randomised controlled trial designed to assess the effect of an intervention. PMID:26978655

  11. Defining Feasibility and Pilot Studies in Preparation for Randomised Controlled Trials: Development of a Conceptual Framework.

    PubMed

    Eldridge, Sandra M; Lancaster, Gillian A; Campbell, Michael J; Thabane, Lehana; Hopewell, Sally; Coleman, Claire L; Bond, Christine M

    2016-01-01

    We describe a framework for defining pilot and feasibility studies focusing on studies conducted in preparation for a randomised controlled trial. To develop the framework, we undertook a Delphi survey; ran an open meeting at a trial methodology conference; conducted a review of definitions outside the health research context; consulted experts at an international consensus meeting; and reviewed 27 empirical pilot or feasibility studies. We initially adopted mutually exclusive definitions of pilot and feasibility studies. However, some Delphi survey respondents and the majority of open meeting attendees disagreed with the idea of mutually exclusive definitions. Their viewpoint was supported by definitions outside the health research context, the use of the terms 'pilot' and 'feasibility' in the literature, and participants at the international consensus meeting. In our framework, pilot studies are a subset of feasibility studies, rather than the two being mutually exclusive. A feasibility study asks whether something can be done, should we proceed with it, and if so, how. A pilot study asks the same questions but also has a specific design feature: in a pilot study a future study, or part of a future study, is conducted on a smaller scale. We suggest that to facilitate their identification, these studies should be clearly identified using the terms 'feasibility' or 'pilot' as appropriate. This should include feasibility studies that are largely qualitative; we found these difficult to identify in electronic searches because researchers rarely used the term 'feasibility' in the title or abstract of such studies. Investigators should also report appropriate objectives and methods related to feasibility; and give clear confirmation that their study is in preparation for a future randomised controlled trial designed to assess the effect of an intervention.

  12. Ice‐water immersion and delayed‐onset muscle soreness: a randomised controlled trial

    PubMed Central

    Sellwood, Kylie Louise; Brukner, Peter; Williams, David; Nicol, Alastair; Hinman, Rana

    2007-01-01

    Objective To determine if ice‐water immersion after eccentric quadriceps exercise minimises the symptoms of delayed‐onset muscle soreness (DOMS). Design A prospective randomised double‐blind controlled trial was undertaken. 40 untrained volunteers performed an eccentric loading protocol with their non‐dominant leg. Interventions Participants were randomised to three 1‐min immersions in either ice water (5±1°C) or tepid water (24°C). Main outcome measures Pain and tenderness (visual analogue scale), swelling (thigh circumference), function (one‐legged hop for distance), maximal isometric strength and serum creatine kinase (CK) recorded at baseline, 24, 48 and 72 h after exercise. Changes in outcome measures over time were compared to determine the effect of group allocation using independent t tests or Mann–Whitney U tests. Results No significant differences were observed between groups with regard to changes in most pain parameters, tenderness, isometric strength, swelling, hop‐for‐distance or serum CK over time. There was a significant difference in pain on sit‐to‐stand at 24 h, with the intervention group demonstrating a greater increase in pain than the control group (median change 8.0 vs 2.0 mm, respectively, p = 0.009). Conclusions The protocol of ice‐water immersion used in this study was ineffectual in minimising markers of DOMS in untrained individuals. This study challenges the wide use of this intervention as a recovery strategy by athletes. PMID:17261562

  13. Rofecoxib versus ibuprofen for acute treatment of migraine: a randomised placebo controlled trial

    PubMed Central

    Misra, U; Jose, M; Kalita, J

    2004-01-01

    Background: Rofecoxib is a potent cyclo-oxygenase-2 inhibitor with a long duration of action. Its role in migraine has not been systematically evaluated. Aim: To study the efficacy of rofecoxib in migraine. Method: In a randomised placebo controlled trial rofecoxib 25 mg, ibuprofen 400 mg, and placebo were compared regarding their efficacy in relieving acute migraine attack. Migraine patients with 2–6 attacks per month were recruited. Headache severity, functional disability, and severity of associated symptoms were graded on a 0–3 scale. The primary endpoint was pain relief at two hours. Relief of associated symptoms and sustained pain relief for 24 hours were also noted. Result: One hundred and twenty four patients were randomised into rofecoxib (42), ibuprofen (40), and placebo (42) groups. One hundred and one patients were followed up: 33 on rofecoxib, 35 ibuprofen, and 33 placebo. Patients' ages ranged from 16–62 (mean 31.4) years, and 83 were females. Pain relief at two hours was noted in 45.5% on rofecoxib, 55.6% on ibuprofen, and 9.1% in the placebo group. The associated symptoms at two hours were reduced in 39.4% on rofecoxib, 50% on ibuprofen, and 9.1% in the placebo group. Sustained 24 hour pain relief was noted in 36.4% on rofecoxib, 41% on ibuprofen, and 6.1% in the placebo group. In the ibuprofen group, five patients had abdominal pain but there were no side effects in those on rofecoxib or in the control group. Both rofecoxib and ibuprofen were significantly effective in relieving pain, associated symptoms at two hours, and in sustained pain relief. There was no significant difference between rofecoxib and ibuprofen in aborting acute migraine attacks. Conclusions: Both ibuprofen and rofecoxib were superior to placebo in aborting an acute migraine attack, and there was no significant difference in their efficacy in an acute migraine attack. PMID:15579612

  14. How do parents experience being asked to enter a child in a randomised controlled trial?

    PubMed Central

    Shilling, Valerie; Young, Bridget

    2009-01-01

    Background As the number of randomised controlled trials of medicines for children increases, it becomes progressively more important to understand the experiences of parents who are asked to enrol their child in a trial. This paper presents a narrative review of research evidence on parents' experiences of trial recruitment focussing on qualitative research, which allows them to articulate their views in their own words. Discussion Parents want to do their best for their children, and socially and legally their role is to care for and protect them yet the complexities of the medical and research context can challenge their fulfilment of this role. Parents are simultaneously responsible for their child and cherish this role yet they are dependent on others when their child becomes sick. They are keen to exercise responsibility for deciding to enter a child in a trial yet can be fearful of making the 'wrong' decision. They make judgements about the threat of the child's condition as well as the risks of the trial yet their interpretations often differ from those of medical and research experts. Individual parents will experience these and other complexities to a greater or lesser degree depending on their personal experiences and values, the medical situation of their child and the nature of the trial. Interactions at the time of trial recruitment offer scope for negotiating these complexities if practitioners have the flexibility to tailor discussions to the needs and situation of individual parents. In this way, parents may be helped to retain a sense that they have acted as good parents to their child whatever decision they make. Summary Discussing randomised controlled trials and gaining and providing informed consent is challenging. The unique position of parents in giving proxy consent for their child adds to this challenge. Recognition of the complexities parents face in making decisions about trials suggests lines for future research on the conduct of trials

  15. Metabolic benefits of dietary prebiotics in human subjects: a systematic review of randomised controlled trials.

    PubMed

    Kellow, Nicole J; Coughlan, Melinda T; Reid, Christopher M

    2014-04-14

    Complex relationships exist between the gut microflora and their human hosts. Emerging evidence suggests that bacterial dysbiosis within the colon may be involved in the pathogenesis of the metabolic syndrome, type 2 diabetes and CVD. The use of dietary prebiotic supplements to restore an optimal balance of intestinal flora may positively affect host metabolism, representing a potential treatment strategy for individuals with cardiometabolic disorders. The present review aimed to examine the current evidence supporting that dietary prebiotic supplementation in adults has beneficial effects on biochemical parameters associated with the development of metabolic abnormalities including obesity, glucose intolerance, dyslipidaemia, hepatic steatosis and low-grade chronic inflammation. Between January 2000 and September 2013, eight computer databases were searched for randomised controlled trials published in English. Human trials were included if at least one group received a dietary prebiotic intervention. In the present review, twenty-six randomised controlled trials involving 831 participants were included. Evidence indicated that dietary prebiotic supplementation increased self-reported feelings of satiety in healthy adults (standardised mean difference -0.57, 95% CI -1.13, -0.01). Prebiotic supplementation also significantly reduced postprandial glucose (-0.76, 95% CI -1.41, -0.12) and insulin (-0.77, 95% CI -1.50, -0.04) concentrations. The effects of dietary prebiotics on total energy intake, body weight, peptide YY and glucagon-like peptide-1 concentrations, gastric emptying times, insulin sensitivity, lipids, inflammatory markers and immune function were contradictory. Dietary prebiotic consumption was found to be associated with subjective improvements in satiety and reductions in postprandial glucose and insulin concentrations. Additional evidence is required before recommending prebiotic supplements to individuals with metabolic abnormalities. Large

  16. Systematic review of randomised controlled trials of strategies to promote adherence to tuberculosis treatment.

    PubMed Central

    Volmink, J.; Garner, P.

    1997-01-01

    OBJECTIVE: To determine the effectiveness of strategies to promote adherence to treatment for tuberculosis. IDENTIFICATION: Searches in Medline (1966 to August 1996), the Cochrane trials register (up to October 1996), and LILACS (Literatura Latinoamericana y del Caribe en Ciencias de la Salud) (1982 to September 1996); screening of references in articles on compliance and adherence; contact with experts in research on tuberculosis and adherence. INCLUSION CRITERIA: Randomised or pseudorandomised controlled trials of interventions to promote adherence with curative or preventive treatment for tuberculosis, with at least one measure of adherence. MAIN OUTCOME MEASURE: Relative risks and 95% confidence intervals for estimates of effect for categorical outcomes. RESULTS: Five trials met the inclusion criteria. The relative risk for tested reminder cards sent to patients who defaulted on treatment was 1.2 (95% confidence interval 1.1 to 1.4), for help given to patients by lay health workers 1.4 (1.1 to 1.8), for monetary incentives offered to patients 1.6 (1.3 to 2.0), for health education 1.2 (1.1 to 1.4), for a combination of a patient incentive and health education 2.4 (1.5 to 3.7) or 1.1 (1.0 to 1.2), and for intensive supervision of staff in tuberculosis clinics 1.2 (1.1 to 1.3). There were no completed trials of directly observed treatment. All of the interventions tested improved adherence. On current evidence it is unclear whether health education by itself leads to better adherence to treatment. CONCLUSIONS: Reliable evidence is available to show some specific strategies improve adherence to tuberculosis treatment, and these should be adopted in health systems, depending on their appropriateness to practice circumstances. Further innovations require testing to help find specific approaches that will be useful in low income countries. Randomised controlled trials evaluating the independent effects of directly observed treatment are awaited. PMID:9418086

  17. A robust adaptive load frequency control for micro-grids.

    PubMed

    Khooban, Mohammad-Hassan; Niknam, Taher; Blaabjerg, Frede; Davari, Pooya; Dragicevic, Tomislav

    2016-11-01

    The goal of this study is to introduce a novel robust load frequency control (LFC) strategy for micro-grid(s) (MG(s)) in islanded mode operation. Admittedly, power generators in MG(s) cannot supply steady electric power output and sometimes cause unbalance between supply and demand. Battery energy storage system (BESS) is one of the effective solutions to these problems. Due to the high cost of the BESS, a new idea of Vehicle-to-Grid (V2G) is that a battery of Electric-Vehicle (EV) can be applied as a tantamount large-scale BESS in MG(s). As a result, a new robust control strategy for an islanded micro-grid (MG) is introduced that can consider electric vehicles׳ (EV(s)) effect. Moreover, in this paper, a new combination of the General Type II Fuzzy Logic Sets (GT2FLS) and the Modified Harmony Search Algorithm (MHSA) technique is applied for adaptive tuning of proportional-integral (PI) controller. Implementing General Type II Fuzzy Systems is computationally expensive. However, using a recently introduced α-plane representation, GT2FLS can be seen as a composition of several Interval Type II Fuzzy Logic Systems (IT2FLS) with a corresponding level of α for each. Real-data from an offshore wind farm in Sweden and solar radiation data in Aberdeen (United Kingdom) was used in order to examine the performance of the proposed novel controller. A comparison is made between the achieved results of Optimal Fuzzy-PI (OFPI) controller and those of Optimal Interval Type II Fuzzy-PI (IT2FPI) controller, which are of most recent advances in the area at hand. The Simulation results prove the successfulness and effectiveness of the proposed controller.

  18. Robust observer-based adaptive fuzzy sliding mode controller

    NASA Astrophysics Data System (ADS)

    Oveisi, Atta; Nestorović, Tamara

    2016-08-01

    In this paper, a new observer-based adaptive fuzzy integral sliding mode controller is proposed based on the Lyapunov stability theorem. The plant is subjected to a square-integrable disturbance and is assumed to have mismatch uncertainties both in state- and input-matrices. Based on the classical sliding mode controller, the equivalent control effort is obtained to satisfy the sufficient requirement of sliding mode controller and then the control law is modified to guarantee the reachability of the system trajectory to the sliding manifold. In order to relax the norm-bounded constrains on the control law and solve the chattering problem of sliding mode controller, a fuzzy logic inference mechanism is combined with the controller. An adaptive law is then introduced to tune the parameters of the fuzzy system on-line. Finally, for evaluating the controller and the robust performance of the closed-loop system, the proposed regulator is implemented on a real-time mechanical vibrating system.

  19. Impact on Caesarean section rates following injections of sterile water (ICARIS): a multicentre randomised controlled trial

    PubMed Central

    2013-01-01

    Background Sterile water injections have been used as an effective intervention for the management of back pain during labour. The objective of the current research is to determine if sterile water injections, as an intervention for back pain in labour, will reduce the intrapartum caesarean section rate. Methods/design Design: A double blind randomised placebo controlled trial Setting: Maternity hospitals in Australia Participants: 1866 women in labour, ≥18 years of age who have a singleton pregnancy with a fetus in a cephalic presentation at term (between 37 + 0 and 41 + 6 weeks gestation), who assess their back pain as equal to or greater than seven on a visual analogue scale when requesting analgesia and able to provide informed consent. Intervention: Participants will be randomised to receive either 0.1 to 0.3 millilitres of sterile water or a normal saline placebo via four intradermal injections into four anatomical points surrounding the Michaelis’ rhomboid over the sacral area. Two injections will be administered over the posterior superior iliac spine (PSIS) and the remaining two at two centimetres posterior, and one centimetre medial to the PSIS respectively. Main outcome measure:Proportion of women who have a caesarean section in labour. Randomisation: Permuted blocks stratified by research site. Blinding (masking):Double-blind trial in which participants, clinicians and research staff blinded to group assignment. Funding:Funded by the National Health and Medical Research Council Trial registration:Australian New Zealand Clinical Trials Registry (No ACTRN12611000221954). Discussion Sterile water injections, which may have a positive effect on reducing the CS rate, have been shown to be a safe and simple analgesic suitable for most maternity settings. A procedure that could reduce intervention rates without adversely affecting safety for mother and baby would benefit Australian families and taxpayers and would reduce requirements for maternal operating

  20. Acupuncture for menopausal vasomotor symptoms: study protocol for a randomised controlled trial

    PubMed Central

    2014-01-01

    Background Hot flushes and night sweats (vasomotor symptoms) are common menopausal symptoms, often causing distress, sleep deprivation and reduced quality of life. Although hormone replacement therapy is an effective treatment, there are concerns about serious adverse events. Non-hormonal pharmacological therapies are less effective and can also cause adverse effects. Complementary therapies, including acupuncture, are commonly used for menopausal vasomotor symptoms. While the evidence for the effectiveness of acupuncture in treating vasomotor symptoms is inconclusive, acupuncture has a low risk of adverse effects, and two small studies suggest it may be more effective than non-insertive sham acupuncture. Our objective is to assess the efficacy of needle acupuncture in improving hot flush severity and frequency in menopausal women. Our current study design is informed by methods tested in a pilot study. Methods/design This is a stratified, parallel, randomised sham-controlled trial with equal allocation of participants to two trial groups. We are recruiting 360 menopausal women experiencing a minimum average of seven moderate hot flushes a day over a seven-day period and who meet diagnostic criteria for the Traditional Chinese Medicine diagnosis of Kidney Yin deficiency. Exclusion criteria include breast cancer, surgical menopause, and current hormone replacement therapy use. Eligible women are randomised to receive either true needle acupuncture or sham acupuncture with non-insertive (blunt) needles for ten treatments over eight weeks. Participants are blinded to treatment allocation. Interventions are provided by Chinese medicine acupuncturists who have received specific training on trial procedures. The primary outcome measure is hot flush score, assessed using the validated Hot Flush Diary. Secondary outcome measures include health-related quality of life, anxiety and depression symptoms, credibility of the sham treatment, expectancy and beliefs about

  1. Prophylactic antibiotic regimens in tumour surgery (PARITY): protocol for a multicentre randomised controlled study

    PubMed Central

    Ghert, Michelle; Deheshi, Benjamin; Holt, Ginger; Randall, R Lor; Ferguson, Peter; Wunder, Jay; Turcotte, Robert; Werier, Joel; Clarkson, Paul; Damron, Timothy; Benevenia, Joseph; Anderson, Megan; Gebhardt, Mark; Isler, Marc; Mottard, Sophie; Healey, John; Evaniew, Nathan; Racano, Antonella; Sprague, Sheila; Swinton, Marilyn; Bryant, Dianne; Thabane, Lehana; Guyatt, Gordon; Bhandari, Mohit

    2012-01-01

    Introduction Limb salvage with endoprosthetic reconstruction is the standard of care for the management of lower-extremity bone tumours in skeletally mature patients. The risk of deep postoperative infection in these procedures is high and the outcomes can be devastating. The most effective prophylactic antibiotic regimen remains unknown, and current clinical practice is highly varied. This trial will evaluate the effect of varying postoperative prophylactic antibiotic regimens on the incidence of deep infection following surgical excision and endoprosthetic reconstruction of lower-extremity bone tumours. Methods and analysis This is a multicentre, blinded, randomised controlled trial, using a parallel two-arm design. 920 patients 15 years of age or older from 12 tertiary care centres across Canada and the USA who are undergoing surgical excision and endoprosthetic reconstruction of a primary bone tumour will receive either short (24 h) or long (5 days) duration postoperative antibiotics. Exclusion criteria include prior surgery or infection within the planned operative field, known colonisation with methicillin-resistant Staphylococcus aureus or vancomycin-resistant Enterococcus at enrolment, or allergy to the study antibiotics. The primary outcome will be rates of deep postoperative infections in each arm. Secondary outcomes will include type and frequency of antibiotic-related adverse events, patient functional outcomes and quality-of-life scores, reoperation and mortality. Randomisation will be blocked, with block sizes known only to the methods centre responsible for randomisation, and stratified by location of tumour and study centre. Patients, care givers and a Central Adjudication Committee will be blinded to treatment allocation. The analysis to compare groups will be performed using Cox regression and log-rank tests to compare survival functions at α=0.05. Ethics and dissemination This study has ethics approval from the McMaster University

  2. Robust algebraic image enhancement for intelligent control systems

    NASA Technical Reports Server (NTRS)

    Lerner, Bao-Ting; Morrelli, Michael

    1993-01-01

    Robust vision capability for intelligent control systems has been an elusive goal in image processing. The computationally intensive techniques a necessary for conventional image processing make real-time applications, such as object tracking and collision avoidance difficult. In order to endow an intelligent control system with the needed vision robustness, an adequate image enhancement subsystem capable of compensating for the wide variety of real-world degradations, must exist between the image capturing and the object recognition subsystems. This enhancement stage must be adaptive and must operate with consistency in the presence of both statistical and shape-based noise. To deal with this problem, we have developed an innovative algebraic approach which provides a sound mathematical framework for image representation and manipulation. Our image model provides a natural platform from which to pursue dynamic scene analysis, and its incorporation into a vision system would serve as the front-end to an intelligent control system. We have developed a unique polynomial representation of gray level imagery and applied this representation to develop polynomial operators on complex gray level scenes. This approach is highly advantageous since polynomials can be manipulated very easily, and are readily understood, thus providing a very convenient environment for image processing. Our model presents a highly structured and compact algebraic representation of grey-level images which can be viewed as fuzzy sets.

  3. Robust control of novel pendulum-type vibration isolation system

    NASA Astrophysics Data System (ADS)

    Tsai, Meng-Shiun; Sun, Yann-Shuoh; Liu, Chun-Hsieh

    2011-08-01

    A novel pendulum-type vibration isolation system is proposed consisting of three active cables with embedded piezoelectric actuators and a passive elastomer layer. The dynamic response of the isolation module in the vertical and horizontal directions is modeled using the Lagrangian approach. The validity of the dynamic model is confirmed by comparing the simulation results for the frequency response in the vertical and horizontal directions with the experimental results. An approximate model is proposed to take into account system uncertainties such as payload changes and hysteresis effects. A robust quantitative feedback theory (QFT)-based active controller is then designed to ensure that the active control can achieve a high level of disturbance rejection in the low-frequency range even under variable loading conditions. It is shown that the controller achieves average disturbance rejection of -14 dB in the 2-60 Hz bandwidth range and -35 dB at the resonance frequency. The experimental results confirm that the proposed system achieves a robust vibration isolation performance under the payload in the range of 40-60 kg.

  4. Robust Inversion and Data Compression in Control Allocation

    NASA Technical Reports Server (NTRS)

    Hodel, A. Scottedward

    2000-01-01

    We present an off-line computational method for control allocation design. The control allocation function delta = F(z)tau = delta (sub 0) (z) mapping commanded body-frame torques to actuator commands is implicitly specified by trim condition delta (sub 0) (z) and by a robust pseudo-inverse problem double vertical line I - G(z) F(z) double vertical line less than epsilon (z) where G(z) is a system Jacobian evaluated at operating point z, z circumflex is an estimate of z, and epsilon (z) less than 1 is a specified error tolerance. The allocation function F(z) = sigma (sub i) psi (z) F (sub i) is computed using a heuristic technique for selecting wavelet basis functions psi and a constrained least-squares criterion for selecting the allocation matrices F (sub i). The method is applied to entry trajectory control allocation for a reusable launch vehicle (X-33).

  5. A randomised controlled trial of an SMS-based mobile epilepsy education system.

    PubMed

    Lua, Pei Lin; Neni, Widiasmoro Selamat

    2013-01-01

    We evaluated an epilepsy education programme based on text messaging (SMS). Epilepsy outpatients from three hospitals in Malaysia were randomised into two groups: intervention and control. Patients in the control group were supplied with printed epilepsy educational material while those in the intervention group also received text messages from the Mobile Epilepsy Educational System (MEES). A total of 136 patients completed the study (mean age 31 years; 91% Malay; 51% with an illness duration of more than 5 years). A between-group analysis showed that the awareness, knowledge and attitudes (AKA) about epilepsy did not significantly differ between the groups at baseline (P > 0.05). The intervention patients reported better AKA levels during follow-up compared to the control patients (P < 0.05). A within-group analysis showed that in intervention patients, there were significant improvements in all AKA domains with larger effect sizes (P < 0.01) while control patients also exhibited significant improvement in most domains except for Awareness but with smaller effect sizes. After controlling for possible confounding variables (age, gender, educational qualification, monthly income and baseline mean for each domain), the intervention group still reported significantly higher AKA than the control group particularly in Awareness (P < 0.001) and Total AKA (P = 0.003). There was also significantly better medication adherence and clinic attendance in the intervention group (P < 0.05). The results suggest that the addition of the MEES to conventional epilepsy education is effective in improving AKA.

  6. Active structural vibration control: Robust to temperature variations

    NASA Astrophysics Data System (ADS)

    Gupta, Vivek; Sharma, Manu; Thakur, Nagesh

    2012-11-01

    d-form augmented piezoelectric constitutive equations which take into account temperature dependence of piezoelectric strain coefficient (d31) and permittivity (∈33), are converted into e-form. Using e-form constitutive equations, a finite element model of a smart two dimensional plate instrumented with piezoelectric patches is derived. Equations of motion are derived using Hamilton's variational principle. Coupled equations of motion are uncoupled using modal analysis. Modal state vectors are estimated using the Kalman observer. The first mode of smart cantilevered plate is actively controlled using negative first modal velocity feedback at various temperatures. Total control effort required to do so is calculated using the electro-mechanical impedance method. The temperature dependence of sensor voltage, control voltage, control effort and Kalman observer equations is shown analytically. Simulation results are presented using MATLAB. Variations in (i) peak sensor voltage, (ii) actual and estimated first modal velocities, (iii) peak control voltage, (iv) total control effort and (v) settling time with respect to temperature are presented. Active vibration control performance is not maintained at temperature away from reference temperature when the temperature dependence of piezoelectric stress coefficient ‘e31' and permittivity ‘∈33' is not included in piezoelectric constitutive equations. Active control of vibrations becomes robust to temperature variations when the temperature dependence of ‘e31' and ‘∈33' is included in piezoelectric constitutive equations.

  7. Robust Decentralized Nonlinear Control for a Twin Rotor MIMO System.

    PubMed

    Belmonte, Lidia María; Morales, Rafael; Fernández-Caballero, Antonio; Somolinos, José Andrés

    2016-07-27

    This article presents the design of a novel decentralized nonlinear multivariate control scheme for an underactuated, nonlinear and multivariate laboratory helicopter denominated the twin rotor MIMO system (TRMS). The TRMS is characterized by a coupling effect between rotor dynamics and the body of the model, which is due to the action-reaction principle originated in the acceleration and deceleration of the motor-propeller groups. The proposed controller is composed of two nested loops that are utilized to achieve stabilization and precise trajectory tracking tasks for the controlled position of the generalized coordinates of the TRMS. The nonlinear internal loop is used to control the electrical dynamics of the platform, and the nonlinear external loop allows the platform to be perfectly stabilized and positioned in space. Finally, we illustrate the theoretical control developments with a set of experiments in order to verify the effectiveness of the proposed nonlinear decentralized feedback controller, in which a comparative study with other controllers is performed, illustrating the excellent performance of the proposed robust decentralized control scheme in both stabilization and trajectory tracking tasks.

  8. Robust Decentralized Nonlinear Control for a Twin Rotor MIMO System

    PubMed Central

    Belmonte, Lidia María; Morales, Rafael; Fernández-Caballero, Antonio; Somolinos, José Andrés

    2016-01-01

    This article presents the design of a novel decentralized nonlinear multivariate control scheme for an underactuated, nonlinear and multivariate laboratory helicopter denominated the twin rotor MIMO system (TRMS). The TRMS is characterized by a coupling effect between rotor dynamics and the body of the model, which is due to the action-reaction principle originated in the acceleration and deceleration of the motor-propeller groups. The proposed controller is composed of two nested loops that are utilized to achieve stabilization and precise trajectory tracking tasks for the controlled position of the generalized coordinates of the TRMS. The nonlinear internal loop is used to control the electrical dynamics of the platform, and the nonlinear external loop allows the platform to be perfectly stabilized and positioned in space. Finally, we illustrate the theoretical control developments with a set of experiments in order to verify the effectiveness of the proposed nonlinear decentralized feedback controller, in which a comparative study with other controllers is performed, illustrating the excellent performance of the proposed robust decentralized control scheme in both stabilization and trajectory tracking tasks. PMID:27472338

  9. Digital robust control law synthesis using constrained optimization

    NASA Technical Reports Server (NTRS)

    Mukhopadhyay, Vivekananda

    1989-01-01

    Development of digital robust control laws for active control of high performance flexible aircraft and large space structures is a research area of significant practical importance. The flexible system is typically modeled by a large order state space system of equations in order to accurately represent the dynamics. The active control law must satisy multiple conflicting design requirements and maintain certain stability margins, yet should be simple enough to be implementable on an onboard digital computer. Described here is an application of a generic digital control law synthesis procedure for such a system, using optimal control theory and constrained optimization technique. A linear quadratic Gaussian type cost function is minimized by updating the free parameters of the digital control law, while trying to satisfy a set of constraints on the design loads, responses and stability margins. Analytical expressions for the gradients of the cost function and the constraints with respect to the control law design variables are used to facilitate rapid numerical convergence. These gradients can be used for sensitivity study and may be integrated into a simultaneous structure and control optimization scheme.

  10. DiPALS: Diaphragm Pacing in patients with Amyotrophic Lateral Sclerosis - a randomised controlled trial.

    PubMed Central

    McDermott, Christopher J; Bradburn, Mike J; Maguire, Chin; Cooper, Cindy L; Baird, Wendy O; Baxter, Susan K; Cohen, Judith; Cantrill, Hannah; Dixon, Simon; Ackroyd, Roger; Baudouin, Simon; Bentley, Andrew; Berrisford, Richard; Bianchi, Stephen; Bourke, Stephen C; Darlison, Roy; Ealing, John; Elliott, Mark; Fitzgerald, Patrick; Galloway, Simon; Hamdalla, Hisham; Hanemann, C Oliver; Hughes, Philip; Imam, Ibrahim; Karat, Dayalan; Leek, Roger; Maynard, Nick; Orrell, Richard W; Sarela, Abeezar; Stradling, John; Talbot, Kevin; Taylor, Lyn; Turner, Martin; Simonds, Anita K; Williams, Tim; Wedzicha, Wisia; Young, Carolyn; Shaw, Pamela J

    2016-01-01

    BACKGROUND Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease resulting in death, usually from respiratory failure, within 2-3 years of symptom onset. Non-invasive ventilation (NIV) is a treatment that when given to patients in respiratory failure leads to improved survival and quality of life. Diaphragm pacing (DP), using the NeuRx/4(®) diaphragm pacing system (DPS)™ (Synapse Biomedical, Oberlin, OH, USA), is a new technique that may offer additional or alternative benefits to patients with ALS who are in respiratory failure. OBJECTIVE The Diaphragm Pacing in patients with Amyotrophic Lateral Sclerosis (DiPALS) trial evaluated the effect of DP on survival over the study duration in patients with ALS with respiratory failure. DESIGN The DiPALS trial was a multicentre, parallel-group, open-label, randomised controlled trial incorporating health economic analyses and a qualitative longitudinal substudy. PARTICIPANTS Eligible participants had a diagnosis of ALS (ALS laboratory-supported probable, clinically probable or clinically definite according to the World Federation of Neurology revised El Escorial criteria), had been stabilised on riluzole for 30 days, were aged ≥ 18 years and were in respiratory failure. We planned to recruit 108 patients from seven UK-based specialist ALS or respiratory centres. Allocation was performed using 1 : 1 non-deterministic minimisation. INTERVENTIONS Participants were randomised to either standard care (NIV alone) or standard care (NIV) plus DP using the NeuRX/4 DPS. MAIN OUTCOME MEASURES The primary outcome was overall survival, defined as the time from randomisation to death from any cause. Secondary outcomes were patient quality of life [assessed by European Quality of Life-5 Dimensions, three levels (EQ-5D-3L), Short Form questionnaire-36 items and Sleep Apnoea Quality of Life Index questionnaire]; carer quality of life (EQ-5D-3L and Caregiver Burden Inventory); cost-utility analysis and health

  11. Study protocol for the randomised controlled trial: combined multimarker screening and randomised patient treatment with ASpirin for evidence-based PREeclampsia prevention (ASPRE)

    PubMed Central

    O'Gorman, Neil; Wright, David; Rolnik, Daniel L; Nicolaides, Kypros H; Poon, Liona C

    2016-01-01

    Introduction Pre-eclampsia (PE) affects 2–3% of all pregnancies and is a major cause of maternal and perinatal morbidity and mortality. Prophylactic use of low-dose aspirin in women at risk for PE may substantially reduce the prevalence of the disease. Effective screening for PE requiring delivery before 37 weeks (preterm PE) can be provided by a combination of maternal factors, uterine artery Doppler, mean arterial pressure, maternal serum pregnancy-associated plasma protein A and placental growth factor at 11–13 weeks' gestation, with a detection rate of 75% at a false-positive rate of 10%. We present a protocol (V.6, date 25 January 2016) for the ASpirin for evidence-based PREeclampsia prevention (ASPRE) trial, which is a double-blinded, placebo-controlled, randomised controlled trial (RCT) that uses an effective PE screening programme to determine whether low-dose aspirin given to women from 11 to 13 weeks' gestation will reduce the incidence of preterm PE. Methods and analysis All eligible women attending for their first trimester scan will be invited to participate in the screening study for preterm PE. Those found to be at high risk of developing preterm PE will be invited to participate in the RCT. Further scans will be conducted for assessment of fetal growth and biomarkers. Pregnancy and neonatal outcomes will be collected and analysed. The first enrolment for the pilot study was in April 2014. As of April 2016, 26 670 women have been screened and 1760 recruited to the RCT. The study is registered on the International Standard Randomised Controlled Trial Number (ISRCTN) registry. Trial registration number ISRCTN13633058. PMID:27354081

  12. Randomised placebo controlled trial of nebulised corticosteroids in acute respiratory syncytial viral bronchiolitis

    PubMed Central

    Cade, A; Brownlee, K; Conway, S; Haigh, D; Short, A; Brown, J; Dassu, D; Mason, S; Phillips, A; Eglin, R; Graham, M; Chetcuti, A; Chatrath, M; Hudson, N; Thomas, A; Chetcuti, P

    2000-01-01

    OBJECTIVE—To evaluate short and long term effects of giving nebulised budesonide early in respiratory syncytial viral (RSV) bronchiolitis.
DESIGN—A multicentre randomised double blind placebo controlled trial.
SUBJECTS—Infants admitted to hospital with their first episode of RSV positive bronchiolitis.
INTERVENTION—Randomisation to receive either 1 mg of nebulised budesonide (Bud) or placebo (Pla) twice daily from admission until 2 weeks after discharge. Follow up was for 12months.
MAIN OUTCOME MEASURES—Duration of hospital admission, time taken to become symptom free, re-admission rates, general practitioner consultation rates, and use of antiwheeze medication during follow up.
RESULTS—161 infants were studied. Both arms were similar with respect to initial clinical severity, age, sex, socioeconomic class, and tobacco exposure. Median time from first nebulisation to discharge: Bud and Pla, 2 days. Median number of days for 50% of infants to be symptom free for 48 hours: Bud, 10 days; Pla, 12 days. Respiratory re-admission rates in the 12 month follow up: Bud, 16%; Pla, 18%; median difference (95% confidence interval (CI)), −2 (−14 to 10). Median respiratory related general practitioner attendances: Bud, 4.0; Pla, 4.5; median difference (95% CI), −1 (−2 to 0). Percentage of infants receiving at least one prescription for antiwheeze medication during follow up, corticosteroids: Bud, 50%; Pla, 60%; difference (95% CI), −10 (−26 to 6); bronchodilators: Bud, 60%; Pla, 67%; difference (95% CI), −7 (−22 to 8).
CONCLUSIONS—There are no short or long term clinical benefits from the administration of nebulised corticosteroids in the acute phase of RSV bronchiolitis.

 PMID:10648365

  13. Buprenorphine versus dihydrocodeine for opiate detoxification in primary care: a randomised controlled trial

    PubMed Central

    Wright, Nat MJ; Sheard, Laura; Tompkins, Charlotte NE; Adams, Clive E; Allgar, Victoria L; Oldham, Nicola S

    2007-01-01

    Background Many drug users present to primary care requesting detoxification from illicit opiates. There are a number of detoxification agents but no recommended drug of choice. The purpose of this study is to compare buprenorphine with dihydrocodeine for detoxification from illicit opiates in primary care. Methods Open label randomised controlled trial in NHS Primary Care (General Practices), Leeds, UK. Sixty consenting adults using illicit opiates received either daily sublingual buprenorphine or daily oral dihydrocodeine. Reducing regimens for both interventions were at the discretion of prescribing doctor within a standard regimen of not more than 15 days. Primary outcome was abstinence from illicit opiates at final prescription as indicated by a urine sample. Secondary outcomes during detoxification period and at three and six months post detoxification were recorded. Results Only 23% completed the prescribed course of detoxification medication and gave a urine sample on collection of their final prescription. Risk of non-completion of detoxification was reduced if allocated buprenorphine (68% vs 88%, RR 0.58 CI 0.35–0.96, p = 0.065). A higher proportion of people allocated to buprenorphine provided a clean urine sample compared with those who received dihydrocodeine (21% vs 3%, RR 2.06 CI 1.33–3.21, p = 0.028). People allocated to buprenorphine had fewer visits to professional carers during detoxification and more were abstinent at three months (10 vs 4, RR 1.55 CI 0.96–2.52) and six months post detoxification (7 vs 3, RR 1.45 CI 0.84–2.49). Conclusion Informative randomised trials evaluating routine care within the primary care setting are possible amongst drug using populations. This small study generates unique data on commonly used treatment regimens. PMID:17210079

  14. AspiriN To Inhibit SEPSIS (ANTISEPSIS) randomised controlled trial protocol

    PubMed Central

    Eisen, Damon P; Moore, Elizabeth M; Leder, Karin; Lockery, Jessica; McBryde, Emma S; McNeil, John J; Pilcher, David; Wolfe, Rory; Woods, Robyn L

    2017-01-01

    Introduction Sepsis is a leading global cause of morbidity and mortality, and is more common at the extremes of age. Moreover, the cost of in-hospital care for elderly patients with sepsis is significant. There are indications from experimental and observational studies that aspirin may reduce inflammation associated with infection. This paper describes the rationale and design of the AspiriN To Inhibit SEPSIS (ANTISEPSIS) trial, a substudy of ASPirin in Reducing Events in the Elderly (ASPREE). ANTISEPSIS primarily aims to determine whether low-dose aspirin reduces sepsis-related deaths in older people. Additionally, it will assess whether low-dose aspirin reduces sepsis-related hospitalisations and sepsis-related Intensive Care Unit (ICU) admissions. Methods and analysis ASPREE is a double-blinded, randomised, placebo-controlled primary prevention trial that will determine whether daily low-dose aspirin extends disability-free longevity in 19 000 healthy older people recruited in Australia and the USA. The ANTISEPSIS substudy involves additional ASPREE trial data collection to assess the impact of daily low-dose aspirin on sepsis-related events in the 16 703 ASPREE participants aged 70 years and over, recruited in Australia. The intervention is a daily 100 mg dose of enteric-coated aspirin versus matching placebo, with 1:1 randomisation. The primary outcome for the ANTISEPSIS substudy is the incidence of sepsis-related death in eligible patients. The incidence of sepsis-related hospital and ICU admissions are secondary outcomes. ANTISEPSIS is to be conducted between 2012 and 2018. Discussion This substudy will determine whether aspirin, an inexpensive and accessible therapy, safely reduces sepsis-related deaths and hospitalisations in older Australians. If shown to be the case, this would have profound effects on the health of older Australians. Trial registration number Pre-results, ACTRN12613000349741. PMID:28110287

  15. Ciprofloxacin DPI: a randomised, placebo-controlled, phase IIb efficacy and safety study on cystic fibrosis

    PubMed Central

    Dorkin, Henry L; Staab, Doris; Operschall, Elisabeth; Alder, Jeff; Criollo, Margarita

    2015-01-01

    Background Treatment of infective bronchitis involving Pseudomonas aeruginosa is a cornerstone of care in patients with cystic fibrosis (CF). This phase IIb, randomised, double-blind, placebo-controlled study assessed the efficacy and safety of ciprofloxacin dry powder for inhalation (DPI) in this population. Methods Patients with CF, ≥12 years of age (N=286), were randomised to ciprofloxacin DPI (32.5 mg (n=93) or 48.75 mg (n=93)), or corresponding placebo (32.5 mg, n=65; 48.75 mg, n=35) twice daily for 28 days. The primary objective was the change in forced expiratory volume in 1 s (FEV1) from baseline (day 0) to end of treatment (day 29) in the intent-to-treat population for ciprofloxacin DPI compared with the corresponding placebo group. Results The primary effectiveness objective was not met; there were no significant differences in change in FEV1 between ciprofloxacin DPI and the corresponding placebo group for either dose (p=0.154). However, in pooled analyses, FEV1 decline from baseline to treatment end was significantly lower with ciprofloxacin DPI than with placebo (pooled data; p=0.02). Ciprofloxacin DPI showed positive effects on sputum bacterial load and quality of life, but these effects were not maintained at the 4-week follow-up. Ciprofloxacin DPI was well tolerated and there were no significant differences in type/incidence of treatment-emergent adverse events by treatment group (p=0.115). Conclusions Further investigations are needed to determine the full scope of the beneficial effects of ciprofloxacin DPI for patients with CF. Trial registration number Clinicaltrials.gov NCT00645788; EudraCT 2008-008314-40. PMID:26688732

  16. Vaginal repair with mesh versus colporrhaphy for prolapse: a randomised controlled trial

    PubMed Central

    Carey, M; Higgs, P; Goh, J; Lim, J; Leong, A; Krause, H; Cornish, A

    2009-01-01

    Objective To compare vaginal repair augmented by mesh with traditional colporrhaphy for the treatment of pelvic organ prolapse. Design Prospective randomised controlled trial. Setting Tertiary teaching hospital. Population One hundred and thirty-nine women with stage ≥2 prolapse according to the pelvic organ prolapse quantification (POP-Q) system requiring both anterior and posterior compartment repair. Methods Subjects were randomised to anterior and posterior vaginal repair with mesh augmentation (mesh group, n= 69) or traditional anterior and posterior colporrhaphy (no mesh group, n= 70). Main outcome measures The primary outcome was the absence of POP-Q stage ≥2 prolapse at 12 months. Secondary outcomes were symptoms, quality-of-life outcomes and satisfaction with surgery. Complications were also reported. Results For subjects attending the 12-month review, success in the mesh group was 81.0% (51 of 63 subjects) compared with 65.6% (40/61) in the no mesh group and was not significantly different (P-value = 0.07). A high level of satisfaction with surgery and improvements in symptoms and quality-of-life data were observed at 12 months compared to baseline in both groups, but there was no significant difference in these outcomes between the two groups. Vaginal mesh exposure occurred in four women in the mesh group (5.6%). De novo dyspareunia was reported by five of 30 (16.7%) sexually active women in the mesh group and five of 33 (15.2%) in the no mesh group at 12 months. Conclusion In this study, vaginal surgery augmented by mesh did not result in significantly less recurrent prolapse than traditional colporrhaphy 12 months following surgery. PMID:19583714

  17. Compression stockings in the management of fractures of the ankle: a randomised controlled trial.

    PubMed

    Sultan, M J; Zhing, T; Morris, J; Kurdy, N; McCollum, C N

    2014-08-01

    In this randomised controlled trial, we evaluated the role of elastic compression using ankle injury stockings (AIS) in the management of fractures of the ankle. A total of 90 patients with a mean age of 47 years (16 to 79) were treated within 72 hours of presentation with a fracture of the ankle, 31 of whom were treated operatively and 59 conservatively, were randomised to be treated either with compression by AIS plus an Aircast boot or Tubigrip plus an Aircast boot. Male to female ratio was 36:54. The primary outcome measure was the functional Olerud-Molander ankle score (OMAS). The secondary outcome measures were; the American Orthopaedic Foot and Ankle Society score (AOFAS); the Short Form (SF)-12v2 Quality of Life score; and the frequency of deep vein thrombosis (DVT). Compression using AIS reduced swelling of the ankle at all time points and improved the mean OMAS score at six months to 98 (95% confidence interval (CI) 96 to 99) compared with a mean of 67 (95% CI 62 to 73) for the Tubigrip group (p < 0.001). The mean AOFAS and SF-12v2 scores at six months were also significantly improved by compression. Of 86 patients with duplex imaging at four weeks, five (12%) of 43 in the AIS group and ten (23%) of 43 in the Tubigrip group developed a DVT (p = 0.26). Compression improved functional outcome and quality of life following fracture of the ankle. DVTs were frequent, but a larger study would be needed to confirm that compression with AISs reduces the incidence of DVT.

  18. Water-based exercise in COPD with physical comorbidities: a randomised controlled trial.

    PubMed

    McNamara, Renae J; McKeough, Zoe J; McKenzie, David K; Alison, Jennifer A

    2013-06-01

    Land-based exercise is often difficult for people with chronic obstructive pulmonary disease (COPD) who have coexisting obesity or musculoskeletal or neurological conditions. This randomised controlled trial aimed to determine the effectiveness of water-based exercise training in improving exercise capacity and quality of life compared to land-based exercise training and control (no exercise) in people with COPD and physical comorbidities. Participants referred to pulmonary rehabilitation were randomly allocated to a water-based exercise, land-based exercise or the control group. The two exercise groups trained for 8 weeks, completing three sessions per week. 45 out of 53 participants (mean ± SD age 72 ± 9 years; forced expiratory volume in 1 s 59 ± 15% predicted) completed the study. Compared to controls, water-based exercise training significantly increased 6-min walking distance, incremental and endurance shuttle walk distances, and improved Chronic Respiratory Disease Questionnaire (CRDQ) dyspnoea and fatigue. Compared to land-based exercise training, water-based exercise training significantly increased incremental shuttle walk distance (mean difference 39 m, 95% CI 5-72 m), endurance shuttle walk distance (mean difference 228 m, 95% CI 19-438 m) and improved CRDQ fatigue. Water-based exercise training was significantly more effective than land-based exercise training and control in increasing peak and endurance exercise capacity and improving aspects of quality of life in people with COPD and physical comorbidities.

  19. A community empowerment strategy embedded in a routine dengue vector control programme: a cluster randomised controlled trial.

    PubMed

    Castro, Marta; Sánchez, Lizet; Pérez, Dennis; Carbonell, Nestor; Lefèvre, Pierre; Vanlerberghe, Veerle; Van der Stuyft, Patrick

    2012-05-01

    The non-sustainability of vertically organised dengue vector control programmes led to pleas for changing the emphasis towards community-based strategies. We conducted a cluster randomised controlled trial with 16 intervention and 16 control clusters to test the effectiveness of a community empowerment strategy intertwined with the routine dengue vector control programme in La Lisa, Havana City, Cuba. The intervention included four components on top of routine control: organisation and management; entomological risk surveillance; capacity building; and community work for vector control. In the control clusters, routine activities continued without interference. The community participation score increased from 1.4 to 3.4. Good knowledge of breeding sites increased by 52.8% and 27.5% in the intervention and control clusters, respectively. There were no changes in adequate Aedes aegypti control practices at household level in the control clusters, but in the intervention clusters adequacy increased by 36.2%. At baseline, the Breteau indices (BI) were approximately 0.1 and were comparable; they fluctuated over time but became different with the launch of the community-based dengue control activities in the intervention clusters. Over the intervention period, the BI remained 53% (95% CI 22-92%) lower in these clusters than in the control clusters. The empowerment strategy increased community involvement and added effectiveness to routine A. aegypti control.

  20. The effectiveness of brief alcohol interventions delivered by community pharmacists: randomised controlled trial

    PubMed Central

    Norman, Ian; Whittlesea, Cate; Murrells, Trevor; McCambridge, Jim

    2016-01-01

    Background & Aims To undertake the first randomised controlled trial to evaluate the effectiveness of a brief intervention delivered by community pharmacists to reduce hazardous or harmful drinking. Design This parallel group individually randomised trial, allocated participants to brief alcohol intervention (n=205) or a leaflet-only control condition (n=202), with follow-up study after 3 months. Setting 16 community pharmacies in one London borough, UK. Participants 407 pharmacy customers (aged 18 or over) with AUDIT scores 8-19 inclusive. Intervention A brief motivational discussion of approximately 10 minutes duration for which 17 pharmacists received a half-day of training. Measurements Hazardous or harmful drinking was assessed using the Alcohol Use Disorders Identification Test (AUDIT) administered by telephone by a researcher blind to allocation status. The two primary outcomes were: 1) change in AUDIT total scores and 2) the proportions no longer hazardous or harmful drinkers (scoring <8) at three months. The four secondary outcomes were: the three sub-scale scores of the AUDIT (for consumption, problems and dependence), and health status according to the EQ-5D (a standardised instrument for use as a measure of health outcome). Findings At 3 months 326 (80% overall; 82% intervention, 78% control) participants were followed up. The difference in reduction in total AUDIT score (intervention minus control) was −0.57 95% CI −1.59 to 0.45, p = 0.28. The odds ratio for AUDIT <8 (control as reference) was 0.87 95% CI 0.50 to 1.51, p = 0.61). For two of the four secondary outcomes (dependence score: −0.46 95% CI −0.82 to −0.09, p = 0.014; health status score: −0.09 95% CI −0.16 to −0.02, p = 0.013) the control group did better, and in the other two there were no differences (consumption score: −0.05 95% CI −0.54 to 0.44, p = 0.85; non-dependence problems score: −0.13 95% CI −0.66 to 0.41). Sensitivity analyses did not change these findings

  1. Randomised controlled trial of topical kanuka honey for the treatment of rosacea

    PubMed Central

    Braithwaite, Irene; Hunt, Anna; Riley, Judith; Fingleton, James; Kocks, Janwillem; Corin, Andrew; Helm, Colin; Sheahan, Davitt; Tofield, Christopher; Montgomery, Barney; Holliday, Mark; Weatherall, Mark; Beasley, Richard

    2015-01-01

    Objective To investigate the efficacy of topical 90% medical-grade kanuka honey and 10% glycerine (Honevo) as a treatment for rosacea. Design Randomised controlled trial with blinded assessment of primary outcome variable. Setting Outpatient primary healthcare population from 5 New Zealand sites. Participants 138 adults aged ≥16, with a diagnosis of rosacea, and a baseline blinded Investigator Global Assessment of Rosacea Severity Score (IGA-RSS) of ≥2. 69 participants were randomised to each treatment arm. 1 participant was excluded from the Honevo group, and 7 and 15 participants withdrew from the Honevo and control groups, respectively. Interventions Participants were randomly allocated 1:1 to Honevo or control cream (Cetomacrogol), applied twice daily for 8 weeks. Main outcome measures The primary outcome measure was the proportion of participants who had a ≥2 improvement in the 7-point IGA-RSS at week 8 compared to baseline. Secondary outcomes included change in IGA-RSS and subject-rated visual analogue score of change in severity (VAS-CS) on a 100 mm scale (0 mm ‘much worse’, 100 mm ‘much improved’) at weeks 2 and 8. Results 24/68 (34.3%) in the Honevo group and 12/69 (17.4%) in the control group had a ≥2 improvement in IGA-RSS at week 8 compared to baseline (relative risk 2.03; 95% CI 1.11 to 3.72, p=0.020). The change in IGA-RSS for Honevo compared to control at week 2 minus baseline was −1 (Hodges-Lehman estimate, 95% CI −1 to 0, p=0.03), and at week 8 minus baseline was −1 (Hodges-Lehman estimate, 95% CI −1 to 0, p=0.005). The VAS-CS at week 2 was 9.1 (95% CI 3.5 to 14.7), p=0.002, and at week 8 was 12.3 (95% CI 5.7 to 18.9)¸ p<0.001 for Honevo compared to control. Conclusions Honevo is an effective treatment for rosacea. Trial registration number This trial was registered in the Australian and New Zealand Clinical Trials Registry ACTRN12614000004662. PMID:26109117

  2. Genetic and Environmental Control of Neurodevelopmental Robustness in Drosophila.

    PubMed

    Mellert, David J; Williamson, W Ryan; Shirangi, Troy R; Card, Gwyneth M; Truman, James W

    2016-01-01

    Interindividual differences in neuronal wiring may contribute to behavioral individuality and affect susceptibility to neurological disorders. To investigate the causes and potential consequences of wiring variation in Drosophila melanogaster, we focused on a hemilineage of ventral nerve cord interneurons that exhibits morphological variability. We find that late-born subclasses of the 12A hemilineage are highly sensitive to genetic and environmental variation. Neurons in the second thoracic segment are particularly variable with regard to two developmental decisions, whereas its segmental homologs are more robust. This variability "hotspot" depends on Ultrabithorax expression in the 12A neurons, indicating variability is cell-intrinsic and under genetic control. 12A development is more variable and sensitive to temperature in long-established laboratory strains than in strains recently derived from the wild. Strains with a high frequency of one of the 12A variants also showed a high frequency of animals with delayed spontaneous flight initiation, whereas other wing-related behaviors did not show such a correlation and were thus not overtly affected by 12A variation. These results show that neurodevelopmental robustness is variable and under genetic control in Drosophila and suggest that the fly may serve as a model for identifying conserved gene pathways that stabilize wiring in stressful developmental environments. Moreover, some neuronal lineages are variation hotspots and thus may be more amenable to evolutionary change.

  3. Genetic and Environmental Control of Neurodevelopmental Robustness in Drosophila

    PubMed Central

    Mellert, David J.; Williamson, W. Ryan; Shirangi, Troy R.; Card, Gwyneth M.; Truman, James W.

    2016-01-01

    Interindividual differences in neuronal wiring may contribute to behavioral individuality and affect susceptibility to neurological disorders. To investigate the causes and potential consequences of wiring variation in Drosophila melanogaster, we focused on a hemilineage of ventral nerve cord interneurons that exhibits morphological variability. We find that late-born subclasses of the 12A hemilineage are highly sensitive to genetic and environmental variation. Neurons in the second thoracic segment are particularly variable with regard to two developmental decisions, whereas its segmental homologs are more robust. This variability “hotspot” depends on Ultrabithorax expression in the 12A neurons, indicating variability is cell-intrinsic and under genetic control. 12A development is more variable and sensitive to temperature in long-established laboratory strains than in strains recently derived from the wild. Strains with a high frequency of one of the 12A variants also showed a high frequency of animals with delayed spontaneous flight initiation, whereas other wing-related behaviors did not show such a correlation and were thus not overtly affected by 12A variation. These results show that neurodevelopmental robustness is variable and under genetic control in Drosophila and suggest that the fly may serve as a model for identifying conserved gene pathways that stabilize wiring in stressful developmental environments. Moreover, some neuronal lineages are variation hotspots and thus may be more amenable to evolutionary change. PMID:27223118

  4. Effects of American ginseng (Panax quinquefolius) on neurocognitive function: an acute, randomised, double-blind, placebo-controlled, crossover study

    PubMed Central

    Ossoukhova, Anastasia; Owen, Lauren; Ibarra, Alvin; Pipingas, Andrew; He, Kan; Roller, Marc; Stough, Con

    2010-01-01

    Rationale Over the last decade, Asian ginseng (Panax ginseng) has been shown to improve aspects of human cognitive function. American ginseng (Panax quinquefolius) has a distinct ginsenoside profile from P. ginseng, promising cognitive enhancing properties in preclinical studies and benefits processes linked to human cognition. Objectives The availability of a highly standardised extract of P. quinquefolius (Cereboost™) led us to evaluate its neurocognitive properties in humans for the first time. Methods This randomised, double-blind, placebo-controlled, crossover trial (N = 32, healthy young adults) assessed the acute mood, neurocognitive and glycaemic effects of three doses (100, 200 400 mg) of Cereboost™ (P. quinquefolius standardised to 10.65% ginsenosides). Participants' mood, cognitive function and blood glucose were measured 1, 3 and 6 h following administration. Results There was a significant improvement of working memory (WM) performance associated with P. quinquefolius. Corsi block performance was improved by all doses at all testing times. There were differential effects of all doses on other WM tasks which were maintained across the testing day. Choice reaction time accuracy and ‘calmness’ were significantly improved by 100 mg. There were no changes in blood glucose levels. Conclusions This preliminary study has identified robust working memory enhancement following administration of American ginseng. These effects are distinct from those of Asian ginseng and suggest that psychopharmacological properties depend critically on ginsenoside profiles. These results have ramifications for the psychopharmacology of herbal extracts and merit further study using different dosing regimens and in populations where cognition is fragile. PMID:20676609

  5. Robust isothermal electric control of exchange bias at room temperature

    NASA Astrophysics Data System (ADS)

    Binek, Christian

    2011-03-01

    Voltage-controlled spintronics is of particular importance to continue progress in information technology through reduced power consumption, enhanced processing speed, integration density, and functionality in comparison with present day CMOS electronics. Almost all existing and prototypical solid-state spintronic devices rely on tailored interface magnetism, enabling spin-selective transmission or scattering of electrons. Controlling magnetism at thin-film interfaces, preferably by purely electrical means, is a key challenge to better spintronics. Currently, most attempts to electrically control magnetism focus on potentially large magnetoelectric effects of multiferroics. We report on our interest in magnetoelectric Cr 2 O3 (chromia). Robust isothermal electric control of exchange bias is achieved at room temperature in perpendicular anisotropic Cr 2 O3 (0001)/CoPd exchange bias heterostructures. This discovery promises significant implications for potential spintronics. From the perspective of basic science, our finding serves as macroscopic evidence for roughness-insensitive and electrically controllable equilibrium boundary magnetization in magnetoelectric antiferromagnets. The latter evolves at chromia (0001) surfaces and interfaces when chromia is in one of its two degenerate antiferromagnetic single domain states selected via magnetoelectric annealing. Theoretical insight into the boundary magnetization and its role in electrically controlled exchange bias is gained from first-principles calculations and general symmetry arguments. Measurements of spin-resolved ultraviolet photoemission, magnetometry at Cr 2 O3 (0001) surfaces, and detailed investigations of the unique exchange bias properties of Cr 2 O3 (0001)/CoPd including its electric controllability provide macroscopically averaged information about the boundary magnetization of chromia. Laterally resolved X-ray PEEM and temperature dependent MFM reveal detailed microscopic information of the chromia

  6. Robust reliable control design for networked control system with sampling communication

    NASA Astrophysics Data System (ADS)

    Sakthivel, R.; Santra, Srimanta; Mathiyalagan, K.; Su, Hongye

    2015-12-01

    In this article, the problem of robust exponential stability and reliable stabilisation for a class of continuous-time networked control systems (NCSs) with a sample-data controller and unknown time-varying sampling rate is considered. The analysis is based on average dwell-time, Lyapunov-Krasovskii functional and linear matrix inequality (LMI) technique. The delay-dependent criteria are developed for ensuring the robust exponential stability of the considered NCSs. The obtained conditions are formulated in terms of LMIs that can easily be solved by using standard software packages. Furthermore, the result is extended to study the robust stabilisation for NCS with parameter uncertainties. A state feedback controller is constructed in terms of the solution to a set of LMIs, which guarantee the robust exponential stabilisation of NCS and the controller. Finally, numerical examples are presented to illustrate the effectiveness of the obtained results.

  7. Robust and fault tolerant control of modular and reconfigurable robots

    NASA Astrophysics Data System (ADS)

    Abdul, Sajan

    Modular and reconfigurable robot has been one of the main areas of robotics research in recent years due to its wide range of applications, especially in aerospace sector. Dynamic control of manipulators can be performed using joint torque sensing with little information of the link dynamics. From the modular robot perspective, this advantage offered by the torque sensor can be taken to enhance the modularity of the control system. Known modular robots though boast novel and diverse mechanical design on joint modules in one way or another, they still require the whole robot dynamic model for motion control, and modularity offered in the mechanical side does not offer any advantage in the control design. In this work, a modular distributed control technique is formulated for modular and reconfigurable robots that can instantly adapt to robot reconfigurations. Under this control methodology, a modular and reconfigurable robot is stabilized joint by joint, and modules can be added or removed without the need of re-tuning the controller. Model uncertainties associated with load and links are compensated by the use of joint torque sensors. Other model uncertainties at each joint module are compensated by a decomposition based robust controller for each module. The proposed distributed control technique offers a 'modular' approach, featuring a unique joint-by-joint control synthesis of the joint modules. Fault tolerance and fault detection are formulated as a decentralized control problem for modular and reconfigurable robots in this thesis work. The modularity of the system is exploited to derive a strategy dependent only on a single joint module, while eliminating the need for the motion states of other joint modules. While the traditional fault tolerant and detection schemes are suitable for robots with the whole dynamic model, this proposed technique is ideal for modular and reconfigurable robots because of its modular nature. The proposed methods have been

  8. Robust adaptive cruise control of high speed trains.

    PubMed

    Faieghi, Mohammadreza; Jalali, Aliakbar; Mashhadi, Seyed Kamal-e-ddin Mousavi

    2014-03-01

    The cruise control problem of high speed trains in the presence of unknown parameters and external disturbances is considered. In particular a Lyapunov-based robust adaptive controller is presented to achieve asymptotic tracking and disturbance rejection. The system under consideration is nonlinear, MIMO and non-minimum phase. To deal with the limitations arising from the unstable zero-dynamics we do an output redefinition such that the zero-dynamics with respect to new outputs becomes stable. Rigorous stability analyses are presented which establish the boundedness of all the internal states and simultaneously asymptotic stability of the tracking error dynamics. The results are presented for two common configurations of high speed trains, i.e. the DD and PPD designs, based on the multi-body model and are verified by several numerical simulations.

  9. Robust uncalibrated visual servoing control based on disturbance observer.

    PubMed

    Ma, Zhe; Su, Jianbo

    2015-11-01

    In this paper, an uncalibrated visual servoing scheme with optimal disturbance rejection performance is proposed based on disturbance observer (DOB). Comparing with traditional uncalibrated methods, which estimate online the hand-eye relationship characterized by varying image Jacobian, the uncertainty of image Jacobian is eliminated via DOB to approach a given nominal model in this paper. By solving a constrained optimization problem transformed into an H∞ control framework, the disturbance rejection performance is optimized while ensuring the robust stability of the closed-loop visual servoing system. The controller is based on the nominal image Jacobian matrix, thus avoiding singularities and local minima. Simulations and experiments show that the proposed scheme performs better in tracking an object than traditional algorithms. The disturbance and image noise rejection performance is verified.

  10. Preliminary demonstration of a robust controller design method

    NASA Technical Reports Server (NTRS)

    Anderson, L. R.

    1980-01-01

    Alternative computational procedures for obtaining a feedback control law which yields a control signal based on measurable quantitites are evaluated. The three methods evaluated are: (1) the standard linear quadratic regulator design model; (2) minimization of the norm of the feedback matrix, k via nonlinear programming subject to the constraint that the closed loop eigenvalues be in a specified domain in the complex plane; and (3) maximize the angles between the closed loop eigenvectors in combination with minimizing the norm of K also via the constrained nonlinear programming. The third or robust design method was chosen to yield a closed loop system whose eigenvalues are insensitive to small changes in the A and B matrices. The relationship between orthogonality of closed loop eigenvectors and the sensitivity of closed loop eigenvalues is described. Computer programs are described.

  11. Effect of training traditional birth attendants on neonatal mortality (Lufwanyama Neonatal Survival Project): randomised controlled study

    PubMed Central

    Phiri-Mazala, Grace; Guerina, Nicholas G; Kasimba, Joshua; Mulenga, Charity; MacLeod, William B; Waitolo, Nelson; Knapp, Anna B; Mirochnick, Mark; Mazimba, Arthur; Fox, Matthew P; Sabin, Lora; Seidenberg, Philip; Simon, Jonathon L; Hamer, Davidson H

    2011-01-01

    Objective To determine whether training traditional birth attendants to manage several common perinatal conditions could reduce neonatal mortality in the setting of a resource poor country with limited access to healthcare. Design Prospective, cluster randomised and controlled effectiveness study. Setting Lufwanyama, an agrarian, poorly developed district located in the Copperbelt province, Zambia. All births carried out by study birth attendants occurred at mothers’ homes, in rural village settings. Participants 127 traditional birth attendants and mothers and their newborns (3559 infants delivered regardless of vital status) from Lufwanyama district. Interventions Using an unblinded design, birth attendants were cluster randomised to intervention or control groups. The intervention had two components: training in a modified version of the neonatal resuscitation protocol, and single dose amoxicillin coupled with facilitated referral of infants to a health centre. Control birth attendants continued their existing standard of care (basic obstetric skills and use of clean delivery kits). Main outcome measures The primary outcome was the proportion of liveborn infants who died by day 28 after birth, with rate ratios statistically adjusted for clustering. Secondary outcomes were mortality at different time points; and comparison of causes of death based on verbal autopsy data. Results Among 3497 deliveries with reliable information, mortality at day 28 after birth was 45% lower among liveborn infants delivered by intervention birth attendants than control birth attendants (rate ratio 0.55, 95% confidence interval 0.33 to 0.90). The greatest reductions in mortality were in the first 24 hours after birth: 7.8 deaths per 1000 live births for infants delivered by intervention birth attendants compared with 19.9 per 1000 for infants delivered by control birth attendants (0.40, 0.19 to 0.83). Deaths due to birth asphyxia were reduced by 63% among infants delivered by

  12. Comparison communities in a cluster randomised trial innovate in response to 'being controlled'.

    PubMed

    Hawe, Penelope; Riley, Therese; Gartrell, Alexandra; Turner, Karen; Canales, Claudia; Omstead, Darlene

    2015-05-01

    We conducted qualitative interviews among primary health care teams and community agencies in eight communities in Victoria, Australia which had (1) agreed to be part of a universal primary care and community development intervention to reduce post natal depression and promote maternal health; and (2) were randomised to the comparison arm. The purpose was to document their experience with and interpretation of the trial. Although 'control' in a controlled trial refers to the control of confounding of the trial result by factors other than allocation to the intervention, participants interpreted 'control' to mean restrictions on what they were allowed to do during the trial period. They had agreed not to use the Edinburgh Post Natal Depression Scale or the SF 36 in clinical practice and not to implement any of the elements of the intervention. We found that no elements of the intervention were implemented. However, the extension of the trial from three to five years made the trial agreement a strain. The imposition of trial conditions also encouraged a degree of lateral thinking and innovation in service delivery (quality improvement). This may have potentially contributed to the null trial results. The observations invite interrogation of intervention theory and consequent rethinking of the way contamination in a cluster trial is defined.

  13. Stress management and sexual health of young adults: a pilot randomised controlled trial.

    PubMed

    Dimou, P A; Bacopoulou, F; Darviri, C; Chrousos, G P

    2014-01-01

    Young people often experience excessive stress that definitely undermines their sexual life and leads them to adopt risky sexual behaviours. As such, the design and application of a stress management programme in this particular age group is, undoubtedly, a crucial matter. In this parallel randomised controlled trial, 60 psychology students of the Panteion University of Athens, aged 18–20, were randomly assigned to undergo either an 8-week stress management programme (n = 30; diaphragmatic breathing–progressive muscle relaxation and guided imagery, twice a day) or not (n = 30). Self-reported validated measures were used to evaluate stress, stressful life events, health locus of control, general health status, sexual behaviours, sexual desire, satisfaction from sexual life and interpersonal relationships. Between-group analyses revealed statistically significant differences in internal health locus of control and general health evaluation. Within the intervention group analyses showed reductions in BMI, stress, the ‘chance’ subscale of multidimensional health locus of control (MHLC) and greater satisfaction from sexual life. No other significant change was reported. We deem that our results should encourage relevant future studies.

  14. Randomised controlled trial of vancomycin for pseudomembranous colitis and postoperative diarrhoea.

    PubMed

    Keighley, M R; Burdon, D W; Arabi, Y; Williams, J A; Thompson, H; Youngs, D; Johnson, M; Bentley, S; George, R H; Mogg, G A

    1978-12-16

    The efficacy of vancomycin in pseudomembranous colitis was assessed in a prospective randomised controlled trial. Forty-four patients with postoperative diarrhoea were allocated to five days' treatment with either 125 mg vancomycin six-hourly or a placebo. Sixteen patients had high titres of the neutralised faecal toxin characteristic of pseudomembranous colitis; nine received vancomycin and seven placebo. At the end of treatment faecal toxins were present in one patient given vancomycin compared with five of the controls. Vancomycin caused the disappearance of Clostridum difficile from the stool in all except one patient, whereas toxicogenic strains of Cl difficile persisted in all but one of the controls. Histological evidence of psuedomembranous colitis had disappeared by the end of treatment in six out of seven patients given vancomycin compared with only one out of seven patients given vancomycin compared with only one out of five patients given placebo. In patients with faecal toxins bowel habit had returned to normal in seven of the vancomycin group compared with only one of the controls, but there was no significant difference in clinical response among patients without faecaal toxins. The results suggest that vancomycin eliminates toxin-producing Cl difficile from the colon and is associated with rapid clinical and histological improvement in patients with pseudomembranous colitis.

  15. Gum chewing reduces the time to first defaecation after pelvic surgery: A randomised controlled study.

    PubMed

    Tazegül Pekin, A; Kerimoğlu, O Seçilmiş; Doğan, N U; Yılmaz, S A; Kebapcılar, A G; Gençoğlu Bakbak, B B; Çelik, Ç

    2015-01-01

    Post-operative ileus is a major complication that increases the morbidity in patients who had abdominal surgery. Several different procedures have been used to manage bowel function, including adequate pain control, prokinetic drugs and supportive strategies. The present study aimed to assess the effect of chewing gum on bowel recovery in patients undergoing gynaecologic abdominal surgeries. A total of 137 patients were randomised into gum-chewing and control groups. Patients in the gum-chewing group began chewing gum at post-operative 3rd h and chewed gum thereafter every 4 h daily, for 30 min each time. All patients received the same post-operative treatment. Primary outcome measures were the time to first passage of flatus and time to first passage of stool. The secondary outcome measures included the first hearing of normal bowel sounds, nausea and the time until discharge from the hospital. Compared with the control group, the time interval between operation and first flatus was shorter in the gum-chewing group (median, 33 h vs 30 h). However, the difference was not significant (p = 0.381). The first defaecation time was significantly shorter in the gum-chewing group. The median time to first defaecation was 67 (20-105) h in the control group and 45 (12-97) h in the gum-chewing group (p < 0.01). Gum chewing is safe, well tolerated and it allows early defaecation after gynaecologic abdominal surgery.

  16. Randomised controlled trial of animal facilitated therapy with dolphins in the treatment of depression

    PubMed Central

    Antonioli, Christian; Reveley, Michael A

    2005-01-01

    Objective To evaluate the effectiveness of animal facilitated therapy with dolphins, controlling for the influence of the natural setting, in the treatment of mild to moderate depression and in the context of the biophilia hypothesis. Setting The study was carried out in Honduras, and recruitment took place in the United States and Honduras. Design Single blind, randomised, controlled trial. Participants Outpatients, recruited through announcements on the internet, radio, newspapers, and hospitals. Results Of the 30 patients randomly assigned to the two groups of treatment, two dropped out of the treatment group after the first week and three withdrew their consent in the control group after they had been randomly allocated. For the participants who completed the study, the mean severity of the depressive symptoms was more reduced in the treatment group than in the control group (Hamilton rating scale for depression, P = 0.002; Beck depression inventory, P = 0.006). For the sample analysed by modified intention to treat and last observation carried forward, the mean differences for the Hamilton and Beck scores between the two groups was highly significant (P = 0.007 and P = 0.012, respectively). Conclusions The therapy was effective in alleviating symptoms of depression after two weeks of treatment. Animal facilitated therapy with dolphins is an effective treatment for mild to moderate depression, which is based on a holistic approach, through interaction with animals in nature. PMID:16308382

  17. Efficacy of communication skills training on colorectal cancer screening by GPs: a cluster randomised controlled trial.

    PubMed

    Aubin-Auger, I; Laouénan, C; Le Bel, J; Mercier, A; Baruch, D; Lebeau, J P; Youssefian, A; Le Trung, T; Peremans, L; Van Royen, P

    2016-01-01

    Colorectal cancer (CRC) mass screening has been implemented in France since 2008. Participation rates remain too low. The objective of this study was to test if the implementation of a training course focused on communication skills among general practitioners (GP) would increase the delivery of gaiac faecal occult blood test and CRC screening participation among the target population of each participating GP. A cluster randomised controlled trial was conducted with GP's practice as a cluster unit. GPs from practices in the control group were asked to continue their usual care. GPs of the intervention group received a 4-h educational training, built with previous qualitative data on CRC screening focusing on doctor-patient communication with a follow-up of 7 months for both groups. The primary outcome measure was the patients' participation rate in the target population for each GP. Seventeen GPs (16 practices) in intervention group and 28 GPs (19 practices) in control group participated. The patients' participation rate in the intervention group were 36.7% vs. 24.5% in the control group (P = 0.03). Doctor-patient communication should be developed and appear to be one of the possible targets of improvement patients adherence and participation rate in the target population for CRC mass screening.

  18. Topical tranexamic acid as a novel treatment for bleeding peptic ulcer: A randomised controlled trial

    PubMed Central

    Rafeey, Mandana; Shoaran, Maryam; Ghergherechi, Robabeh

    2016-01-01

    Background: Peptic ulcers are among the most common causes of upper gastrointestinal (GI) bleeding in children. The standard care for GI bleeding is endoscopy for diagnostic and therapeutic purposes. We aimed to assess the effect of topical tranexamic acid (TXA) via endoscopic procedures in children with GI bleeding caused by bleeding ulcers. Procedure: In this randomised controlled trial, 120 children were evaluated by diagnostic procedures for GI bleeding, of which 63 (30 girls, 33 boys) aged 1-month to 15 years were recruited. The patients were randomly divided into case and control groups. In the case group, TXA was administered directly under endoscopic therapy. In the control group, epinephrine (1/10,000) was submucosally injected to the four quadrants of ulcer margins as the routine endoscopic therapy. In both groups, the patients received supportive medical therapy with intravenous fluids and proton pump inhibitor drugs. Results: The mean ± standard deviation age of the children was 5 ± 2.03 years. Rebleeding occurred in 15 (11.4%) and 21 (9.8%) patients in the case and control groups, respectively (P = 0.50). The frequency of blood transfusion episodes (P = 0.06) and duration of hospital stay (P = 0.07) were not statistically different between the groups. Conclusion: Using topical TXA via endoscopic procedures may be effective in cases of GI bleedings caused by active bleeding ulcers. In order to establish this therapeutic effect, a large number of clinical studies are needed. PMID:27251517

  19. Long-term efficacy of resilient appliance therapy in TMD pain patients: a randomised, controlled trial.

    PubMed

    Nilsson, Håkan; Vallon, D; Ekberg, E C

    2011-10-01

    The aim was to investigate long-term efficacy of a resilient appliance in patients with pain due to temporomandibular disorders (TMD). A randomised, controlled trial was performed in 80 recruited TMD pain patients. They were randomly allocated to one of two groups: treatment with a resilient appliance or treatment with a hard, palatal, non-occluding appliance. The primary treatment outcome was judged positive when patients' characteristic pain intensity decreased by at least 30%. Additional treatment outcomes were physical functioning, emotional functioning and headache. At the 12-month follow-up 50% of the patients in the treatment group and 42% in the control group had a 30% reduction of characteristic pain intensity, when calculated in an intent-to-treat analysis. Jaw function improved in both groups at the 6- and 12-month follow-up. Emotional functioning improved in both groups at the 6-month follow-up; an improvement concerning grade of depression was found in the control group at 12 months. Headache decreased in both groups at both follow-ups. There were no statistically significant differences found regarding primary and additional outcomes between groups at the 6- and 12-months follow-up. There was no statistically significant difference between the resilient appliance and the non-occluding control appliance in reducing TMD pain, physical functioning, emotional functioning and headache in a 12 months perspective.

  20. A Robust H ∞ Controller for an UAV Flight Control System.

    PubMed

    López, J; Dormido, R; Dormido, S; Gómez, J P

    2015-01-01

    The objective of this paper is the implementation and validation of a robust H ∞ controller for an UAV to track all types of manoeuvres in the presence of noisy environment. A robust inner-outer loop strategy is implemented. To design the H ∞ robust controller in the inner loop, H ∞ control methodology is used. The two controllers that conform the outer loop are designed using the H ∞ Loop Shaping technique. The reference vector used in the control architecture formed by vertical velocity, true airspeed, and heading angle, suggests a nontraditional way to pilot the aircraft. The simulation results show that the proposed control scheme works well despite the presence of noise and uncertainties, so the control system satisfies the requirements.

  1. A Robust H ∞ Controller for an UAV Flight Control System

    PubMed Central

    López, J.; Dormido, R.; Dormido, S.; Gómez, J. P.

    2015-01-01

    The objective of this paper is the implementation and validation of a robust H ∞ controller for an UAV to track all types of manoeuvres in the presence of noisy environment. A robust inner-outer loop strategy is implemented. To design the H ∞ robust controller in the inner loop, H ∞ control methodology is used. The two controllers that conform the outer loop are designed using the H ∞ Loop Shaping technique. The reference vector used in the control architecture formed by vertical velocity, true airspeed, and heading angle, suggests a nontraditional way to pilot the aircraft. The simulation results show that the proposed control scheme works well despite the presence of noise and uncertainties, so the control system satisfies the requirements. PMID:26221622

  2. Telehealth for patients at high risk of cardiovascular disease: pragmatic randomised controlled trial

    PubMed Central

    O’Cathain, Alicia; Thomas, Clare; Edwards, Louisa; Gaunt, Daisy; Dixon, Padraig; Hollinghurst, Sandra; Nicholl, Jon; Large, Shirley; Yardley, Lucy; Fahey, Tom; Foster, Alexis; Garner, Katy; Horspool, Kimberley; Man, Mei-See; Rogers, Anne; Pope, Catherine; Montgomery, Alan A

    2016-01-01

    Objective To assess whether non-clinical staff can effectively manage people at high risk of cardiovascular disease using digital health technologies. Design Pragmatic, multicentre, randomised controlled trial. Setting 42 general practices in three areas of England. Participants Between 3 December 2012 and 23 July 2013 we recruited 641 adults aged 40 to 74 years with a 10 year cardiovascular disease risk of 20% or more, no previous cardiovascular event, at least one modifiable risk factor (systolic blood pressure ≥140 mm Hg, body mass index ≥30, current smoker), and access to a telephone, the internet, and email. Participants were individually allocated to intervention (n=325) or control (n=316) groups using automated randomisation stratified by site, minimised by practice and baseline risk score. Interventions Intervention was the Healthlines service (alongside usual care), comprising regular telephone calls from trained lay health advisors following scripts generated by interactive software. Advisors facilitated self management by supporting participants to use online resources to reduce risk factors, and sought to optimise drug use, improve treatment adherence, and encourage healthier lifestyles. The control group comprised usual care alone. Main outcome measures The primary outcome was the proportion of participants responding to treatment, defined as maintaining or reducing their cardiovascular risk after 12 months. Outcomes were collected six and 12 months after randomisation and analysed masked. Participants were not masked. Results 50% (148/295) of participants in the intervention group responded to treatment compared with 43% (124/291) in the control group (adjusted odds ratio 1.3, 95% confidence interval 1.0 to 1.9; number needed to treat=13); a difference possibly due to chance (P=0.08). The intervention was associated with reductions in blood pressure (difference in mean systolic −2.7 mm Hg (95% confidence interval −4.7 to −0.6 mm Hg

  3. Robust parameter design for automatically controlled systems and nanostructure synthesis

    NASA Astrophysics Data System (ADS)

    Dasgupta, Tirthankar

    2007-12-01

    This research focuses on developing comprehensive frameworks for developing robust parameter design methodology for dynamic systems with automatic control and for synthesis of nanostructures. In many automatically controlled dynamic processes, the optimal feedback control law depends on the parameter design solution and vice versa and therefore an integrated approach is necessary. A parameter design methodology in the presence of feedback control is developed for processes of long duration under the assumption that experimental noise factors are uncorrelated over time. Systems that follow a pure-gain dynamic model are considered and the best proportional-integral and minimum mean squared error control strategies are developed by using robust parameter design. The proposed method is illustrated using a simulated example and a case study in a urea packing plant. This idea is also extended to cases with on-line noise factors. The possibility of integrating feedforward control with a minimum mean squared error feedback control scheme is explored. To meet the needs of large scale synthesis of nanostructures, it is critical to systematically find experimental conditions under which the desired nanostructures are synthesized reproducibly, at large quantity and with controlled morphology. The first part of the research in this area focuses on modeling and optimization of existing experimental data. Through a rigorous statistical analysis of experimental data, models linking the probabilities of obtaining specific morphologies to the process variables are developed. A new iterative algorithm for fitting a Multinomial GLM is proposed and used. The optimum process conditions, which maximize the above probabilities and make the synthesis process less sensitive to variations of process variables around set values, are derived from the fitted models using Monte-Carlo simulations. The second part of the research deals with development of an experimental design methodology, tailor

  4. Effectiveness of topiramate for tobacco dependence in patients with depression; a randomised, controlled trial

    PubMed Central

    Campayo, Javier García; Sobradiel, Natalia; Alda, Marta; Mas, Adoración; Andrés, Eva; Magallón, Rosa; Crucelaegui, Arantxa; Sanz, Beatriz

    2008-01-01

    Background Tobacco dependence management is a multi-component intervention that includes pharmacological treatments such as Nicotine Substitution Therapy (NST) or bupropion, and psychological therapy. There are some preliminary reports on topiramate efficacy for tobacco dependence. The aim of this study is to determine whether topiramate is as effective as the standard NST treatment for tobacco cessation at 1-year follow-up in patients with depression. Method/design Design: A randomised, controlled trial involving two groups, one of which is the control group consisting of patients on the standard pharmacological treatment for tobacco cessation (NST) and the other is the intervention group consisting of patients on topiramate as pharmacological treatment. Setting: 29 primary care health centres in the city of Zaragoza, Spain. Sample: 180 patients, aged 18–65 years, diagnosed with major depression, smoke more than 20 cigarettes/day, who have voluntarily asked for tobacco cessation therapy. Intervention: A multi-component programme for tobacco cessation is offered to all of the patients in the study. This programme is made up of pharmacological therapy + group cognitive-behavioural therapy. Pharmacological therapy consists of NST for the control group and topiramate (200 mg/day) for the intervention group. Psychological therapy is made up of 16 sessions of manualised group therapy. Measurements: Cessation will be assessed by patient self-declared abstinence, expired air carbon monoxide levels, and cotinine levels in saliva. Questionnaires on tobacco dependence, anxiety, depression, impulsiveness and self-efficacy will be administered. The interviewers will not know which group the patient belongs to (blind). The assessments will be carried out at baseline, D (cessation day) -1, D+1, weeks 1, 2, 3, 4, 6, 8, 10 and 13, and months 4, 5, 6, 8, 10 and 12. Main variables: Tobacco cessation rates and tobacco dependence. Analysis: The analysis will be per intent to treat

  5. Effect of intermittent feedback control on robustness of human-like postural control system.

    PubMed

    Tanabe, Hiroko; Fujii, Keisuke; Suzuki, Yasuyuki; Kouzaki, Motoki

    2016-03-02

    Humans have to acquire postural robustness to maintain stability against internal and external perturbations. Human standing has been recently modelled using an intermittent feedback control. However, the causality inside of the closed-loop postural control system associated with the neural control strategy is still unknown. Here, we examined the effect of intermittent feedback control on postural robustness and of changes in active/passive components on joint coordinative structure. We implemented computer simulation of a quadruple inverted pendulum that is mechanically close to human tiptoe standing. We simulated three pairs of joint viscoelasticity and three choices of neural control strategies for each joint: intermittent, continuous, or passive control. We examined postural robustness for each parameter set by analysing the region of active feedback gain. We found intermittent control at the hip joint was necessary for model stabilisation and model parameters affected the robustness of the pendulum. Joint sways of the pendulum model were partially smaller than or similar to those of experimental data. In conclusion, intermittent feedback control was necessary for the stabilisation of the quadruple inverted pendulum. Also, postural robustness of human-like multi-link standing would be achieved by both passive joint viscoelasticity and neural joint control strategies.

  6. Effect of intermittent feedback control on robustness of human-like postural control system

    PubMed Central

    Tanabe, Hiroko; Fujii, Keisuke; Suzuki, Yasuyuki; Kouzaki, Motoki

    2016-01-01

    Humans have to acquire postural robustness to maintain stability against internal and external perturbations. Human standing has been recently modelled using an intermittent feedback control. However, the causality inside of the closed-loop postural control system associated with the neural control strategy is still unknown. Here, we examined the effect of intermittent feedback control on postural robustness and of changes in active/passive components on joint coordinative structure. We implemented computer simulation of a quadruple inverted pendulum that is mechanically close to human tiptoe standing. We simulated three pairs of joint viscoelasticity and three choices of neural control strategies for each joint: intermittent, continuous, or passive control. We examined postural robustness for each parameter set by analysing the region of active feedback gain. We found intermittent control at the hip joint was necessary for model stabilisation and model parameters affected the robustness of the pendulum. Joint sways of the pendulum model were partially smaller than or similar to those of experimental data. In conclusion, intermittent feedback control was necessary for the stabilisation of the quadruple inverted pendulum. Also, postural robustness of human-like multi-link standing would be achieved by both passive joint viscoelasticity and neural joint control strategies. PMID:26931281

  7. Effect of intermittent feedback control on robustness of human-like postural control system

    NASA Astrophysics Data System (ADS)

    Tanabe, Hiroko; Fujii, Keisuke; Suzuki, Yasuyuki; Kouzaki, Motoki

    2016-03-01

    Humans have to acquire postural robustness to maintain stability against internal and external perturbations. Human standing has been recently modelled using an intermittent feedback control. However, the causality inside of the closed-loop postural control system associated with the neural control strategy is still unknown. Here, we examined the effect of intermittent feedback control on postural robustness and of changes in active/passive components on joint coordinative structure. We implemented computer simulation of a quadruple inverted pendulum that is mechanically close to human tiptoe standing. We simulated three pairs of joint viscoelasticity and three choices of neural control strategies for each joint: intermittent, continuous, or passive control. We examined postural robustness for each parameter set by analysing the region of active feedback gain. We found intermittent control at the hip joint was necessary for model stabilisation and model parameters affected the robustness of the pendulum. Joint sways of the pendulum model were partially smaller than or similar to those of experimental data. In conclusion, intermittent feedback control was necessary for the stabilisation of the quadruple inverted pendulum. Also, postural robustness of human-like multi-link standing would be achieved by both passive joint viscoelasticity and neural joint control strategies.

  8. Lyapunov function-based control laws for revolute robot arms - Tracking control, robustness, and adaptive control

    NASA Technical Reports Server (NTRS)

    Wen, John T.; Kreutz-Delgado, Kenneth; Bayard, David S.

    1992-01-01

    A new class of joint level control laws for all-revolute robot arms is introduced. The analysis is similar to a recently proposed energy-like Liapunov function approach, except that the closed-loop potential function is shaped in accordance with the underlying joint space topology. This approach gives way to a much simpler analysis and leads to a new class of control designs which guarantee both global asymptotic stability and local exponential stability. When Coulomb and viscous friction and parameter uncertainty are present as model perturbations, a sliding mode-like modification of the control law results in a robustness-enhancing outer loop. Adaptive control is formulated within the same framework. A linear-in-the-parameters formulation is adopted and globally asymptotically stable adaptive control laws are derived by simply replacing unknown model parameters by their estimates (i.e., certainty equivalence adaptation).

  9. Robust control of mitotic spindle orientation in the developing epidermis

    PubMed Central

    Poulson, Nicholas D.

    2010-01-01

    Progenitor cells must balance self-amplification and production of differentiated progeny during development and homeostasis. In the epidermis, progenitors divide symmetrically to increase surface area and asymmetrically to promote stratification. In this study, we show that individual epidermal cells can undergo both types of division, and therefore, the balance is provided by the sum of individual cells’ choices. In addition, we define two control points for determining a cell’s mode of division. First is the expression of the mouse Inscuteable gene, which is sufficient to drive asymmetric cell division (ACD). However, there is robust control of division orientation as excessive ACDs are prevented by a change in the localization of NuMA, an effector of spindle orientation. Finally, we show that p63, a transcriptional regulator of stratification, does not control either of these processes. These data have uncovered two important regulatory points controlling ACD in the epidermis and allow a framework for analysis of how external cues control this important choice. PMID:21098114

  10. Robust Thermal Control of Propulsion Lines for Space Missions

    NASA Technical Reports Server (NTRS)

    Bhandari, Pradeep

    2011-01-01

    A document discusses an approach to insulating propulsion lines for spacecraft. In spacecraft that have propulsion lines that are located externally with open bus architecture, the lines are typically insulated by Multi Layer Insulation (MLI) blankets. MLI on propulsion lines tends to have large and somewhat random variances in its heat loss properties (effective emittance) from one location to the next, which makes it an un-robust approach to control propulsion line temperatures. The approach described here consists of a clamshell design in which the inner surface of the shell is coated with low-emissivity aluminized Kapton tape, and the outer surface is covered with black tape. This clamshell completely encloses the propulsion line. The line itself is covered with its heater, which in turn, is covered completely with black tape. This approach would be low in heater power needs because even though the outer surface of the prop line (and its heater) is covered with black tape as well as the outer surface of the clamshell, the inner surface of the clamshell is covered with low-emissivity aluminized Kapton tape. Hence, the heat loss from the line will be small and comparable to the MLI based one. In terms of contamination changing the radiative properties of surfaces, since the clamshell s inner surface is always protected during handling and is only installed after all the work on the prop line has been completed, the controlling surface, which is the clamshell s inner surface, is always in pristine condition. This proposed design allows for a much more deterministic and predictable design using a very simple and implementable approach for thermal control. It also uses low heater power and is robust to handling and contamination during and after implementation.

  11. Robust Diffeomorphic Mapping via Geodesically Controlled Active Shapes

    PubMed Central

    Tward, Daniel J.; Ma, Jun; Miller, Michael I.; Younes, Laurent

    2013-01-01

    This paper presents recent advances in the use of diffeomorphic active shapes which incorporate the conservation laws of large deformation diffeomorphic metric mapping. The equations of evolution satisfying the conservation law are geodesics under the diffeomorphism metric and therefore termed geodesically controlled diffeomorphic active shapes (GDAS). Our principal application in this paper is on robust diffeomorphic mapping methods based on parameterized surface representations of subcortical template structures. Our parametrization of the GDAS evolution is via the initial momentum representation in the tangent space of the template surface. The dimension of this representation is constrained using principal component analysis generated from training samples. In this work, we seek to use template surfaces to generate segmentations of the hippocampus with three data attachment terms: surface matching, landmark matching, and inside-outside modeling from grayscale T1 MR imaging data. This is formulated as an energy minimization problem, where energy describes shape variability and data attachment accuracy, and we derive a variational solution. A gradient descent strategy is employed in the numerical optimization. For the landmark matching case, we demonstrate the robustness of this algorithm as applied to the workflow of a large neuroanatomical study by comparing to an existing diffeomorphic landmark matching algorithm. PMID:23690757

  12. The effect of chlorhexidine in reducing oral colonisation in geriatric patients: a randomised controlled trial

    PubMed Central

    Sharif-Abdullah, Sharifah Shafinaz Binti; Chong, Mei Chan; Surindar-Kaur, Surat Singh; Kamaruzzaman, Shahrul Bahyah; Ng, Kwan Hoong

    2016-01-01

    INTRODUCTION Inadequate oral care has been implicated in the development of aspiration pneumonia in frail geriatric patients and is a major cause of mortality, due to the colonisation of microbes in vulnerable patients. This type of pneumonia has been associated with an increase in respiratory pathogens in the oral cavity. The aim of this study was to evaluate the effects of chlorhexidine compared to routine oral care in edentulous geriatric inpatients. METHODS A double-blind, parallel-group randomised controlled trial was carried out. The intervention group received oral care with chlorhexidine 0.2%, while the control group received routine oral care with thymol. Nurses provided oral care with assigned solutions of 20 mL once daily over seven days. Oral cavity assessment using the Brief Oral Health Status Examination form was performed before each oral care procedure. Data on medication received and the subsequent development of aspiration pneumonia was recorded. An oral swab was performed on Day 7 to obtain specimens to test for colonisation. RESULTS The final sample consisted of 35 (control) and 43 (intervention) patients. Chlorhexidine was effective in reducing oral colonisation compared to routine oral care with thymol (p < 0.001). The risk of oral bacterial colonisation was nearly three times higher in the thymol group compared to the chlorhexidine group. CONCLUSION The use of chlorhexidine 0.2% significantly reduced oral colonisation and is recommended as an easier and more cost-effective alternative for oral hygiene. PMID:27211885

  13. Sunflower therapy for children with specific learning difficulties (dyslexia): a randomised, controlled trial.

    PubMed

    Bull, Leona

    2007-02-01

    The aim of the study was to determine the clinical and perceived effectiveness of the Sunflower therapy in the treatment of childhood dyslexia. The Sunflower therapy includes applied kinesiology, physical manipulation, massage, homeopathy, herbal remedies and neuro-linguistic programming. A multi-centred, randomised controlled trial was undertaken with 70 dyslexic children aged 6-13 years. The research study aimed to test the research hypothesis that dyslexic children 'feel better' and 'perform better' as a result of treatment by the Sunflower therapy. Children in the treatment group and the control group were assessed using a battery of standardised cognitive, Literacy and self-esteem tests before and after the intervention. Parents of children in the treatment group gave feedback on their experience of the Sunflower therapy. Test scores were compared using the Mann Whitney, and Wilcoxon statistical tests. While both groups of children improved in some of their test scores over time, there were no statistically significant improvements in cognitive or Literacy test performance associated with the treatment. However, there were statistically significant improvements in academic self-esteem, and reading self-esteem, for the treatment group. The majority of parents (57.13%) felt that the Sunflower therapy was effective in the treatment of learning difficulties. Further research is required to verify these findings, and should include a control group receiving a dummy treatment to exclude placebo effects.

  14. A lifestyle intervention for primary care patients with depression and anxiety: A randomised controlled trial.

    PubMed

    Forsyth, Adrienne; Deane, Frank P; Williams, Peter

    2015-12-15

    This study aimed to evaluate the efficacy of a diet and exercise lifestyle intervention on mental health outcomes for patients currently being treated for depression and/or anxiety in primary care. Patients (n=119) referred by general practitioners to the 12-week randomised controlled trial were assigned to either an intervention of six visits to a dual qualified dietitian/exercise physiologist (DEP) where motivational interviewing and activity scheduling were used to engage patients in individually-tailored lifestyle change (focussed on diet and physical activity), or an attention control with scheduled telephone contact. Assessments conducted at baseline (n=94) and 12 weeks (n=60) were analysed with an intent-to-treat approach using linear mixed modelling. Significant improvement was found for both groups on Depression, Anxiety and Stress Scale (DASS) scores, measures of nutrient intake and total Australian modified Healthy Eating Index (Aust-HEI) scores. Significant differences between groups over time were found only for iron intake and body mass index. Patients participating in individual consultations with a dietitian were more likely to maintain or improve diet quality than those participating in an attention control. This study provides initial evidence to support the role of dietitians in the management of patients with depression and/or anxiety.

  15. Internet-Supported Physical Exercise Training for Persons with Multiple Sclerosis—A Randomised, Controlled Study

    PubMed Central

    Tallner, Alexander; Streber, René; Hentschke, Christian; Morgott, Marc; Geidl, Wolfgang; Mäurer, Mathias; Pfeifer, Klaus

    2016-01-01

    Physical exercise is effective in improving functional outcomes in persons with multiple sclerosis (pwMS). We evaluated the feasibility and effectiveness of internet-based exercise training (e-training) for pwMS on health-related quality of life (HrQoL). Secondary outcomes were muscle strength, aerobic capacity, lung function, physical activity, and fatigue. This is a randomised, controlled trial with a wait-list control group. Data were collected at baseline, after three and six months, and analysed using a hybrid linear model. One-hundred twenty-six pwMS participated in the home-based aerobic (1×/week) and strength training (2×/week) intervention that was supervised and documented via an internet-platform. The intervention group received e-training for six months, and the control group received e-training after a three months waiting period. Significant differences between the groups were only observed for muscle strength (knee flexion (effect size ES = 0.3, p = 0.003), knee extension (ES = 0.24, p = 0.015)), peak expiratory flow (ES = 0.2, p = 0.039), and sports activity (ES = 0.33, p = 0.001) after three months. E-training had no effect on HrQoL but did on muscle strength, lung function, and physical activity. It is a promising and feasible approach to facilitate large-scale, yet individual, training support. PMID:27706046

  16. Identification, Uncertainty Characterization and Robust Control Synthesis Applied to Large Flexible Structures Control

    NASA Technical Reports Server (NTRS)

    Bayard, David S.; Chiang, Richard Y.

    1996-01-01

    This paper demonstrates an approach to frequency domain identification for the explicit purpose of designing robust H(infinity) controllers. The approach transforms raw experimental data into a plant set estimate directly usable by modern robust control design software(e.g., Matlab Robust Control Toolboxes [11][2]). A key issue in control design from raw data is the question of whether the controller will work when applied to the true system. The main feature fo this approach is that the resulting controller in guaranteed to work as designed(when applied to the true system) to a prescribed statistical confidence. While the overall methodology addresses key theoretical issues, it has at the same time been specifically designed to support practical implementations. A simulation example is included to demonstrate the overall approach.

  17. The Parameterization of All Robust Stabilizing Simple Repetitive Controllers

    NASA Astrophysics Data System (ADS)

    Yamada, Kou; Sakanushi, Tatsuya; Ando, Yoshinori; Hagiwara, Takaaki; Murakami, Iwanori; Takenaga, Hiroshi; Tanaka, Hiroshi; Matsuura, Shun

    The modified repetitive control system is a type of servomechanism for the periodic reference input. That is, the modified repetitive control system follows the periodic reference input with small steady state error, even if a periodic disturbance or an uncertainty exists in the plant. Using previously proposed modified repetitive controllers, even if the plant does not include time-delay, transfer functions from the periodic reference input to the output and from the disturbance to the output have infinite numbers of poles. When transfer functions from the periodic reference input to the output and from the disturbance to the output have infinite numbers of poles, it is difficult to specify the input-output characteristic and the disturbance attenuation characteristic. From the practical point of view, it is desirable that the input-output characteristic and the disturbance attenuation characteristic are easily specified. In order to specify the input-output characteristic and the disturbance attenuation characteristic easily, transfer functions from the periodic reference input to the output and from the disturbance to the output are desirable to have finite numbers of poles. From this viewpoint, Yamada et al. proposed the concept of simple repetitive control systems such that the controller works as a modified repetitive controller and transfer functions from the periodic reference input to the output and from the disturbance to the output have finite numbers of poles. In addition, Yamada et al. clarified the parameterization of all stabilizing simple repetitive controllers. However, the method by Yamada et al. cannot be applied for the plant with uncertainty. The purpose of this paper is to propose the parameterization of all robust stabilizing simple repetitive controllers for the plant with uncertainty.

  18. A design method for robust stabilizing simple repetitive control systems

    NASA Astrophysics Data System (ADS)

    Yamada, Kou; Takenaga, Hiroshi; Tanaka, Hiroshi

    2007-12-01

    The modified repetitive control system is a type of servomechanism for the periodic reference input. That is, the modified repetitive control system follows the periodic reference input with small steady state error, even if a periodic disturbance or uncertainty exists in the plant. Using previously proposed modified repetitive controllers, even if the plants does not includes time-delay, the transfer function from the periodic reference input to the output and that from the disturbance to the output have an infinite number of poles. When the transfer function from the periodic reference input to the output and that from the disturbance to the output have an infinite number of poles, it is difficult to specify the input-output characteristic and the disturbance attenuation characteristic. From the practical point of view, it is desirable that the input-output characteristic and the disturbance attenuation characteristic are easily specified. In order to specify the input-output characteristic and the disturbance attenuation characteristic easily, the transfer function from the periodic reference input to the output and that from the disturbance to the output are desirable to have a finite number of poles. Yamada et al. proposed the concept of simple repetitive control systems such that the controller works as a modified repetitive controller and the transfer function from the periodic reference input to the output and that from the disturbance to the output have a finite number of poles. In addition, Yamada et al. clarified the parametrization of all stabilizing simple repetitive controllers. However the method by Yamada et al. cannot be applied for the plant with uncertainty. The purpose of this paper is to propose the parametrization of all robust stabilizing simple repetitive controllers for the plant with uncertainty.

  19. Randomised controlled trial evaluation of Tweet2Quit: a social network quit-smoking intervention

    PubMed Central

    Pechmann, Cornelia; Delucchi, Kevin; Lakon, Cynthia M; Prochaska, Judith J

    2016-01-01

    Background We evaluated a novel Twitter-delivered intervention for smoking cessation, Tweet2Quit, which sends daily, automated communications to small, private, self-help groups to encourage high-quality, online, peer-to-peer discussions. Design A 2-group randomised controlled trial assessed the net benefit of adding a Tweet2Quit support group to a usual care control condition of nicotine patches and a cessation website. Participants Participants were 160 smokers (4 cohorts of 40/cohort), aged 18–59 years, who intended to quit smoking, used Facebook daily, texted weekly, and had mobile phones with unlimited texting. Intervention All participants received 56 days of nicotine patches, emails with links to the smokefree.gov cessation website, and instructions to set a quit date within 7 days. Additionally, Tweet2Quit participants were enrolled in 20-person, 100-day Twitter groups, and received daily discussion topics via Twitter, and daily engagement feedback via text. Measures The primary outcome was sustained abstinence at 7, 30 and 60 days post-quit date. Results Participants (mean age 35.7 years, 26.3% male, 31.2% college degree, 88.7% Caucasian) averaged 18.0 (SD=8.2) cigarettes per day and 16.8 (SD=9.8) years of smoking. Participants randomised to Tweet2Quit averaged 58.8 tweets/participant and the average tweeting duration was 47.4 days/participant. Tweet2Quit doubled sustained abstinence out to 60 days follow-up (40.0%, 26/65) versus control (20.0%, 14/70), OR=2.67, CI 1.19 to 5.99, p=0.017. Tweeting via phone predicted tweet volume, and tweet volume predicted sustained abstinence (p<0.001). The daily autocommunications caused tweeting spikes accounting for 24.0% of tweets. Conclusions Tweet2Quit was engaging and doubled sustained abstinence. Its low cost and scalability makes it viable as a global cessation treatment. Trial registration number NCT01602536. PMID:26928205

  20. Acupuncture point injection treatment of primary dysmenorrhoea: a randomised, double blind, controlled study

    PubMed Central

    Wade, C; Wang, L; Zhao, W J; Cardini, F; Kronenberg, F; Gui, S Q; Ying, Z; Zhao, N Q; Chao, M T; Yu, J

    2016-01-01

    Objective To determine if injection of vitamin K3 in an acupuncture point is optimal for the treatment of primary dysmenorrhoea, when compared with 2 other injection treatments. Setting A Menstrual Disorder Centre at a public hospital in Shanghai, China. Participants Chinese women aged 14–25 years with severe primary dysmenorrhoea for at least 6 months not relieved by any other treatment were recruited. Exclusion criteria were the use of oral contraceptives, intrauterine devices or anticoagulant drugs, pregnancy, history of abdominal surgery, participation in other therapies for pain and diagnosis of secondary dysmenorrhoea. Eighty patients with primary dysmenorrhoea, as defined on a 4-grade scale, completed the study. Two patients withdrew after randomisation. Interventions A double-blind, double-dummy, randomised controlled trial compared vitamin K3 acupuncture point injection to saline acupuncture point injection and vitamin K3 deep muscle injection. Patients in each group received 3 injections at a single treatment visit. Primary and secondary outcome measures The primary outcome was the difference in subjective perception of pain as measured by an 11 unit Numeric Rating Scale (NRS). Secondary measurements were Cox Pain Intensity and Duration scales and the consumption of analgesic tablets before and after treatment and during 6 following cycles. Results Patients in all 3 groups experienced pain relief from the injection treatments. Differences in NRS measured mean pain scores between the 2 active control groups were less than 1 unit (−0.71, CI −1.37 to −0.05) and not significant, but the differences in average scores between the treatment hypothesised to be optimal and both active control groups (1.11, CI 0.45 to 1.78) and (1.82, CI 1.45 to 2.49) were statistically significant in adjusted mixed-effects models. Menstrual distress and use of analgesics were diminished for 6 months post-treatment. Conclusions Acupuncture point injection of

  1. Epilation for Minor Trachomatous Trichiasis: Four-Year Results of a Randomised Controlled Trial

    PubMed Central

    Habtamu, Esmael; Rajak, Saul N.; Tadesse, Zerihun; Wondie, Tariku; Zerihun, Mulat; Guadie, Birhan; Gebre, Teshome; Kello, Amir Bedri; Callahan, Kelly; Mabey, David C. W.; Khaw, Peng T.; Gilbert, Clare E.; Weiss, Helen A.; Emerson, Paul M.; Burton, Matthew J.

    2015-01-01

    Background Trachomatous trichiasis (TT) needs to be managed to reduce the risk of vision loss. The long-term impact of epilation (a common traditional practice of repeated plucking of lashes touching the eye) in preventing visual impairment and corneal opacity from TT is unknown. We conducted a randomized controlled trial of epilation versus surgery for the management of minor TT (fewer than six lashes touching the eye) in Ethiopia. Here we report the four-year outcome and the effect on vision and corneal opacity. Methodology/ Principal Findings 1300 individuals with minor TT were recruited and randomly assigned to quality trichiasis surgery or repeated epilation using high quality epilation forceps by a trained person with good near vision. Participants were examined six-monthly for two-years, and then at four-years after randomisation. At two-years all epilation arm participants were offered free surgery. At four-years 1151 (88.5%) were re-examined: 572 (88%) and 579 (89%) from epilation and surgery arms, respectively. At that time, 21.1% of the surgery arm participants had recurrent TT; 189/572 (33%) of the epilation arm had received surgery, while 383 (67%) declined surgery and had continued epilating (“epilation-only”). Among the epilation-only group, 207 (54.1%) fully controlled their TT, 166 (43.3%) had minor TT and 10 (2.6%) had major TT (>5 lashes). There were no differences between participants in the epilation-only, epilation-to-surgery and surgery arm participants in changes in visual acuity and corneal opacity between baseline and four-years. Conclusions/ Significance Most minor TT participants randomised to the epilation arm continued epilating and controlled their TT. Change in vision and corneal opacity was comparable between surgery and epilation-only participants. This suggests that good quality epilation with regular follow-up is a reasonable second-line alternative to surgery for minor TT for individuals who either decline surgery or do not

  2. MObile Technology for Improved Family Planning Services (MOTIF): study protocol for a randomised controlled trial

    PubMed Central

    2013-01-01

    Background Providing women with contraceptive methods following abortion is important to reduce repeat abortion rates, yet evidence for effective post-abortion family planning interventions are limited. This protocol outlines the evaluation of a mobile phone-based intervention using voice messages to support post-abortion family planning in Cambodia. Methods/Design A single blind randomised controlled trial of 500 participants. Clients aged 18 or over, attending for abortion at four Marie Stopes International clinics in Cambodia, owning a mobile phone and not wishing to have a child at the current time are randomised to the mobile phone-based intervention or control (standard care) with a 1:1 allocation ratio. The intervention comprises a series of six automated voice messages to remind clients about available family planning methods and provide a conduit for additional support. Clients can respond to message prompts to request a phone call from a counsellor, or alternatively to state they have no problems. Clients requesting to talk to a counsellor, or who do not respond to the message prompts, receive a call from a Marie Stopes International Cambodia counsellor who provides individualised advice and support regarding family planning. The duration of the intervention is 3 months. The control group receive existing standard of care without the additional mobile phone-based support. We hypothesise that the intervention will remind clients about contraceptive methods available, identify problems with side effects early and provide support, and therefore increase use of post-abortion family planning, while reducing discontinuation and unsafe method switching. Participants are assessed at baseline and at 4 months. The primary outcome measure is use of an effective modern contraceptive method at 4 months post abortion. Secondary outcome measures include contraception use, pregnancy and repeat abortion over the 4-month post-abortion period. Risk ratios will be used as

  3. Exercise for health for early postmenopausal women: a systematic review of randomised controlled trials.

    PubMed

    Asikainen, Tuula-Maria; Kukkonen-Harjula, Katriina; Miilunpalo, Seppo

    2004-01-01

    Women who pass menopause face many changes that may lead to loss of health-related fitness (HRF), especially if sedentary. Many exercise recommendations are also relevant for early postmenopausal women; however, these may not meet their specific needs because the recommendations are based mainly on studies on men. We conducted a systematic review for randomised, controlled exercise trials on postmenopausal women (aged 50 to 65 years) on components of HRF. HRF consists of morphological fitness (body composition and bone strength), musculoskeletal fitness (muscle strength and endurance, flexibility), motor fitness (postural control), cardiorespiratory fitness (maximal aerobic power, blood pressure) and metabolic fitness (lipid and carbohydrate metabolism). The outcome variables chosen were: bodyweight; proportion of body fat of total bodyweight (F%); bone mineral density (BMD); bone mineral content (BMC); various tests on muscle performance, flexibility, balance and coordination; maximal oxygen consumption (V-dotO(2max)); resting blood pressure (BP); total cholesterol (TC); high-density lipoprotein-cholesterol; low-density lipoprotein-cholesterol; triglycerides; blood glucose and insulin. The feasibility of the exercise programme was assessed from drop-out, attendance and injury rates. Twenty-eight randomised controlled trials with 2646 participants were assessed. In total, 18 studies reported on the effects of exercise on bodyweight and F%, 16 on BMD or BMC, 11 on muscular strength or endurance, five on flexibility, six on balance or coordination, 18 on V-dotO(2max), seven on BP, nine on lipids and two studies on glucose an one on insulin. Based on these studies, early postmenopausal women could benefit from 30 minutes of daily moderate walking in one to three bouts combined with a resistance training programme twice a week. For a sedentary person, walking is feasible and can be incorporated into everyday life. A feasible way to start resistance training is to

  4. Evaluation of an online Diabetes Needs Assessment Tool (DNAT) for health professionals: a randomised controlled trial

    PubMed Central

    2009-01-01

    Background Continuous medical education is traditionally reliant to a large extent on self-directed learning based on individuals' perceived learning priorities. Evidence suggests that this ability to self-assess is limited, and more so in the least competent. Therefore, it may be of benefit to utilise some form of external assessment for this purpose. Many diabetes educational programmes have been introduced, but few have been assessed for their benefit in a systematic manner. As diabetes is an increasingly prevalent disease, methods for the dissemination and understanding of clinical guidelines need to be explored for their effectiveness. This paper describes the study design of a randomised controlled trial to evaluate the effectiveness of using an interactive online Diabetes Needs Assessment Tool (DNAT), that builds a learning curriculum based on identified knowledge gaps, compared with conventional self-directed learning. The study assesses the effect of these interventions on health professionals' knowledge of diabetes management, evaluates the acceptability of this process of learning and self-reported changes in clinical practice as a result of this novel educational process. Methods Following a baseline assessment, participants will be randomised to undergo a 4-month learning period where they will either be given access to the diabetes learning modules alone (control group) or a Diabetes Needs Assessment Tool (DNAT) plus the diabetes learning modules (intervention group). On completion of the DNAT, a personalised learning report will be created for each participant identifying needs alongside individualised recommendations of the most appropriate learning modules to meet those requirements. All participants will complete a Diabetes Knowledge Test before and immediately after the allocated learning and the primary outcome will be the state of knowledge at 4 months. Learners will also be surveyed immediately after the learning period to assess the

  5. Physical fitness training in Subacute Stroke (PHYS-STROKE) - study protocol for a randomised controlled trial

    PubMed Central

    2014-01-01

    Background Given the rising number of strokes worldwide, and the large number of individuals left with disabilities after stroke, novel strategies to reduce disability, increase functions in the motor and the cognitive domains, and improve quality of life are of major importance. Physical activity is a promising intervention to address these challenges but, as yet, there is no study demonstrating definite outcomes. Our objective is to assess whether additional treatment in the form of physical fitness-based training for patients early after stroke will provide benefits in terms of functional outcomes, in particular gait speed and the Barthel Index (co-primary outcome measures) reflecting activities of daily living (ADL). We will gather secondary functional outcomes as well as mechanistic parameters in an exploratory approach. Methods/Design Our phase III randomised controlled trial will recruit 215 adults with moderate to severe limitations of walking and ADL 5 to 45 days after stroke onset. Participants will be stratified for the prognostic variables of “centre”, “age”, and “stroke severity”, and randomly assigned to one of two groups. The interventional group receives physical fitness training delivered as supported or unsupported treadmill training (cardiovascular active aerobic training; five times per week, over 4 weeks; each session 50 minutes; total of 20 additional physical fitness training sessions) in addition to standard rehabilitation treatment. The control intervention consists of relaxation sessions (non-cardiovascular active; five times per week week, over 4 weeks; each session 50 minutes) in addition to standard rehabilitation treatment. Co-primary efficacy endpoints will be gait speed (in m/s, 10 m walk) and the Barthel Index (100 points total) at 3 months post-stroke, compared to baseline measurements. Secondary outcomes include standard measures of quality of life, sleep and mood, cognition, arm function, maximal oxygen uptake

  6. Changes in body weight and food choice in those attempting smoking cessation: a cluster randomised controlled trial

    PubMed Central

    2012-01-01

    Background Fear of weight gain is a barrier to smoking cessation and significant cause of relapse for many people. The provision of nutritional advice as part of a smoking cessation programme may assist some in smoking cessation and perhaps limit weight gain. The aim of this study was to determine the effect of a structured programme of dietary advice on weight change and food choice, in adults attempting smoking cessation. Methods Cluster randomised controlled design. Classes randomised to intervention commenced a 24-week intervention, focussed on improving food choice and minimising weight gain. Classes randomised to control received “usual care”. Results Twenty-seven classes in Greater Glasgow were randomised between January and August 2008. Analysis, including those who continued to smoke, showed that actual weight gain and percentage weight gain was similar in both groups. Examination of data for those successful at giving up smoking showed greater mean weight gain in intervention subjects (3.9 (SD 3.1) vs. 2.7 (SD 3.7) kg). Between group differences were not significant (p = 0.23, 95% CI −0.9 to 3.5). In comparison to baseline improved consumption of fruit and vegetables and breakfast cereal were reported in the intervention group. A higher percentage of control participants continued smoking (74% vs. 66%). Conclusions The intervention was not successful at minimising weight gain in comparison to control but was successful in facilitating some sustained improvements in the dietary habits of intervention participants. Improved quit rates in the intervention group suggest that continued contact with advisors may have reduced anxieties regarding weight gain and encouraged cessation despite weight gain. Research should continue in this area as evidence suggests that the negative effects of obesity could outweigh the health benefits achieved through reductions in smoking prevalence. Trial registration Current Controlled Trials ISRCTN73824458 PMID

  7. Robust quantum control using smooth pulses and topological winding.

    PubMed

    Barnes, Edwin; Wang, Xin; Das Sarma, S

    2015-08-04

    The greatest challenge in achieving the high level of control needed for future technologies based on coherent quantum systems is the decoherence induced by the environment. Here, we present an analytical approach that yields explicit constraints on the driving field which are necessary and sufficient to ensure that the leading-order noise-induced errors in a qubit's evolution cancel exactly. We derive constraints for two of the most common types of noise that arise in qubits: slow fluctuations of the qubit energy splitting and fluctuations in the driving field itself. By theoretically recasting a phase in the qubit's wavefunction as a topological winding number, we can satisfy the noise-cancelation conditions by adjusting driving field parameters without altering the target state or quantum evolution. We demonstrate our method by constructing robust quantum gates for two types of spin qubit: phosphorous donors in silicon and nitrogen-vacancy centers in diamond.

  8. Robust quantum control using smooth pulses and topological winding

    PubMed Central

    Barnes, Edwin; Wang, Xin; Das Sarma, S.

    2015-01-01

    The greatest challenge in achieving the high level of control needed for future technologies based on coherent quantum systems is the decoherence induced by the environment. Here, we present an analytical approach that yields explicit constraints on the driving field which are necessary and sufficient to ensure that the leading-order noise-induced errors in a qubit’s evolution cancel exactly. We derive constraints for two of the most common types of noise that arise in qubits: slow fluctuations of the qubit energy splitting and fluctuations in the driving field itself. By theoretically recasting a phase in the qubit’s wavefunction as a topological winding number, we can satisfy the noise-cancelation conditions by adjusting driving field parameters without altering the target state or quantum evolution. We demonstrate our method by constructing robust quantum gates for two types of spin qubit: phosphorous donors in silicon and nitrogen-vacancy centers in diamond. PMID:26239195

  9. Implementation of ‘Goals of Patient Care’ medical treatment orders in residential aged care facilities: protocol for a randomised controlled trial

    PubMed Central

    Martin, Ruth S; Hayes, Barbara J; Hutchinson, Anastasia; Yates, Paul; Lim, Wen Kwang

    2017-01-01

    Introduction Systematic reviews demonstrate that advance care planning (ACP) has many positive effects for residents of aged care facilities, including decreased hospitalisation. The proposed Residential Aged Care Facility (RACF) ‘Goals of Patient Care’ (GOPC) form incorporates a resident's prior advance care plan into medical treatment orders. Where none exists, it captures residents' preferences. This documentation helps guide healthcare decisions made at times of acute clinical deterioration. Methods and analysis This is a mixed methods study. An unblinded cluster randomised controlled trial is proposed in three pairs of RACFs. In the intervention arm, GOPC forms will be completed by a doctor incorporating advance care plans or wishes. In the control arm, residents will have usual care which may include an advance care plan. The primary hypothesis is that the GOPC form is superior to standard ACP alone and will lead to decreased hospitalisation due to clearer documentation of residents' medical treatment plans. The primary outcome will be an analysis of the effect of the GOPC medical treatment orders on emergency department attendances and hospital admissions at 6 months. Secondary outcome measurements will include change in hospitalisation rates at 3 and 12 months, length of stay and external mortality rates among others. Qualitative interviews, 12 months post GOPC implementation, will be used for process evaluation of the GOPC and to evaluate staff perceptions of the form's usefulness for improving communication and medical decision-making at a time of deterioration. Dissemination The results will be disseminated in peer review journals and research conferences. This robust randomised controlled trial will provide high-quality data about the influence of medical treatment orders that incorporate ACP or preferences adding to the current gap in knowledge and evidence in this area. Trial registration number ACTRN12615000298516, Results. PMID:28283490

  10. A randomised controlled pilot feasibility study of the physical and psychological effects of an integrated support programme in breast cancer.

    PubMed

    Baker, Barbara S; Harrington, Julia E; Choi, Beak-San; Kropf, Pascale; Muller, Ingrid; Hoffman, Caroline J

    2012-08-01

    A pilot study was conducted to assess recruitment and effectiveness of an integrated support programme in women with breast cancer. Twelve participants were randomised to receive medical care with or without the support programme. Psychosocial questionnaires and immune/hormonal assays were completed at baseline, three and six months. Recruitment was problematic. In the intervention group, mental fatigue was significantly improved (p = 0.016) compared to controls; increased NK cell activity suggested an improvement in immune function. Total stress (p = 0.009), anxiety (p = 0.032) and endocrine-specific (p = 0.032) symptoms were significantly improved in the controls. A large-scale randomisation trial appears warranted, dependent upon effective recruitment.

  11. A Robust Reinforcement Learning Control Design Method for Nonlinear System with Partially Unknown Structure

    NASA Astrophysics Data System (ADS)

    Nakano, Kazuhiro; Obayashi, Masanao; Kuremoto, Takashi; Kobayashi, Kunikazu

    We propose a robust control system which has robustness for disturbance and can deal with a nonlinear system with partially unknown structure by fusing reinforcement learning and robust control theory. First, we solved an optimal control problem without using unknown part of functions of the system, using neural network and the repetition learning of reinforcement learning algorithm. Second, we built the robust reinforcement learning control system which permits uncertainty and has robustness for disturbance by fusing the idea of H infinity control theory with above system.

  12. Adjunctive rifampicin to reduce early mortality from Staphylococcus aureus bacteraemia (ARREST): study protocol for a randomised controlled trial

    PubMed Central

    2012-01-01

    Background Staphylococcus aureus bacteraemia is a common and serious infection, with an associated mortality of ~25%. Once in the blood, S. aureus can disseminate to infect almost any organ, but bones, joints and heart valves are most frequently affected. Despite the infection’s severity, the evidence guiding optimal antibiotic therapy is weak: fewer than 1,500 patients have been included in 16 randomised controlled trials investigating S. aureus bacteraemia treatment. It is uncertain which antibiotics are most effective, their route of administration and duration, and whether antibiotic combinations are better than single agents. We hypothesise that adjunctive rifampicin, given in combination with a standard first-line antibiotic, will enhance killing of S. aureus early in the treatment course, sterilise infected foci and blood faster, and thereby reduce the risk of dissemination, metastatic infection and death. Our aim is to determine whether adjunctive rifampicin reduces all-cause mortality within 14 days and bacteriological failure or death within 12 weeks from randomisation. Methods We will perform a parallel group, randomised (1:1), blinded, placebo-controlled trial in NHS hospitals across the UK. Adults (≥18 years) with S. aureus (meticillin-susceptible or resistant) grown from at least one blood culture who have received ≤96 h of active antibiotic therapy for the current infection and do not have contraindications to the use of rifampicin will be eligible for inclusion. Participants will be randomised to adjunctive rifampicin (600-900mg/day; orally or intravenously) or placebo for the first 14 days of therapy in combination with standard single-agent antibiotic therapy. The co-primary outcome measures will be all-cause mortality up to 14 days from randomisation and bacteriological failure/death (all-cause) up to 12 weeks from randomisation. 940 patients will be recruited, providing >80% power to detect 45% and 30% reductions in the two co

  13. Randomised controlled trial of local corticosteroid injections for carpal tunnel syndrome in general practice

    PubMed Central

    2010-01-01

    Background Carpal tunnel syndrome is caused by entrapment of the median nerve and results in pain, tingling and numbness in the wrist and hand. It is a common condition in general practice. Effectiveness of treatment by intracarpal corticosteroid injection has never been investigated in general practice. The objective of this study was to determine if corticosteroid injections for carpal tunnel syndrome provided by general practitioners are effective. Methods In this study 69 participants with a clinical diagnosis of carpal tunnel syndrome were recruited from 20 general practices. Short-term outcomes were assessed in a randomised, placebo-controlled trial. Long-term results were assessed in a prospective cohort-study of steroid responders. Participants were randomised to intracarpal injections of 1 ml triamcinolonacetonide 10 mg/ml (TCA) or 1 ml NaCl (placebo). Non-responders to NaCl were treated with additional TCA injections. Main outcomes were immediate treatment success, mean score of the Symptom Severity Scale (SSS) and Functional Status Scale (FSS) of the Boston carpal tunnel questionnaire, subjective improvement and proportion of participants with recurrences during follow-up. Duration of follow-up was twelve months. Results The TCA-group (36 participants) had better outcomes than the NaCl-group (33 participants) during short-term assessment for outcome measures treatment response, mean improvement of SSS-score (the mean difference in change score was 0.637 {95% CI: 0.320, 0.960; p < 0.001}) and FSS-score (the mean difference in change score was 0.588 {95% CI: 0.232, 0.944; p = 0.002}) and perceived improvement (p = 0.01). The number to treat to achieve satisfactory partial treatment response or complete resolution of symptoms and signs was 3 (95% CI:1.83, 9.72). 49% of TCA-responders (17/35) had recurrences during follow-up. In the group of TCA-responders without recurrences (51%, 18/35) outcomes for SSS-score and FSS-score deteriorated during the follow

  14. Randomised controlled trial of local corticosteroid injections for de Quervain's tenosynovitis in general practice

    PubMed Central

    Peters-Veluthamaningal, Cyriac; Winters, Jan C; Groenier, Klaas H; Meyboom-deJong, Betty

    2009-01-01

    Background De Quervain's tenosynovitis is a stenosing tenosynovitis of the first dorsal compartment of the wrist and leads to wrist pain and to impaired function of the wrist and hand. It can be treated by splinting, local corticosteroid injection and operation. In this study effectiveness of local corticosteroid injections for de Quervain's tenosynovitis provided by general practitioners was assessed. Methods Participants with de Quervain's tenosynovitis were recruited by general practitioners. Short-term outcomes (one week after injections) were assessed in a randomised, placebo-controlled trial. Long-term effectiveness was evaluated in an open prospective cohort-study of steroid responders during a follow-up period of 12 months. Participants were randomised to one or two local injections of 1 ml of triamcinolonacetonide (TCA) or 1 ml of NaCl 0.9% (placebo). Non-responders to NaCl were treated with additional TCA injections. Main outcomes were immediate treatment response, severity of pain, improvement as perceived by participant and functional disability using sub items hand and finger function of the Dutch Arthritis Impact Measurement Scale (Dutch AIMS-2-HFF). Results 11 general practitioners included 21 wrists in 21 patients. The TCA-group had better results for short-term outcomes treatment response (78% vs. 25%; p = 0.015), perceived improvement (78% vs. 33%; p = 0.047) and severity of pain (4.27 vs. 1.33; p = 0.031) but not for the Dutch-AIMS-HFF (2.71 vs. 1.92; p = 0.112). Absolute risk reduction for the main outcome short-term treatment response was 0.55 (95% CI: 0.34, 0.76) with a number needed to treat of 2 (95% CI: 1, 3). In the cohort of steroid responders (n = 12) the beneficial effects of steroid injections were sustained during the follow-up of 12 months regarding severity of pain (p = 0.67) and scores of Dutch AIMS-2-HFF (p = 0.36), but not for patient perceived improvement (p = 0.02). No adverse events were observed during the 12 months of follow

  15. Feasibility study of an integrated stroke self-management programme: a cluster-randomised controlled trial

    PubMed Central

    Jones, Fiona; Gage, Heather; Drummond, Avril; Bhalla, Ajay; Grant, Robert; Lennon, Sheila; McKevitt, Christopher; Riazi, Afsane; Liston, Matthew

    2016-01-01

    Objectives To test the feasibility of conducting a controlled trial into the effectiveness of a self-management programme integrated into stroke rehabilitation. Design A feasibility cluster-randomised design was utilised with stroke rehabilitation teams as units of randomisation. Setting Community-based stroke rehabilitation teams in London. Participants 78 patients with a diagnosis of stroke requiring community based rehabilitation. Intervention The intervention consisted of an individualised approach to self-management based on self-efficacy. Clinicians were trained to integrate defined self-management principles into scheduled rehabilitation sessions, supported by a patient-held workbook. Main outcomes measures Patient measures of quality of life, mood, self-efficacy and functional capacity, and health and social care utilisation, were carried out by blinded assessors at baseline, 6 weeks and 12 weeks. Fidelity and acceptability of the delivery were evaluated by observation and interviews. Results 4 community stroke rehabilitation teams were recruited, and received a total of 317 stroke referrals over 14 months. Of these, 138 met trial eligibility criteria and 78 participants were finally recruited (56.5%). Demographic and baseline outcome measures were similar between intervention and control arms, with the exception of age. All outcome measures were feasible to use and clinical data at 12 weeks were completed for 66/78 participants (85%; 95% CI 75% to 92%). There was no significant difference in any of the outcomes between the arms of the trial, but measures of functional capacity and self-efficacy showed responsiveness to the intervention. Observation and interview data confirmed acceptability and fidelity of delivery according to predetermined criteria. Costs varied by site. Conclusions It was feasible to integrate a stroke self-management programme into community rehabilitation, using key principles. Some data were lost to follow-up, but overall

  16. Routine examination of the newborn and maternal satisfaction: a randomised controlled trial

    PubMed Central

    Wolke, D; Dave, S; Hayes, J; Townsend, J; Tomlin, M

    2002-01-01

    Objective: To determine whether the routine examination of the newborn by a midwife compared with a junior paediatrician (SHO) affects maternal satisfaction with this examination. Methods: Randomised controlled trial: 826 mother and baby pairs in a district general hospital in south east England were randomised to a paediatric SHO or a midwife for the routine newborn examination. Maternal satisfaction with the examination was analysed in relation to intervention group, process, and background variables. Results: Some 81% of mothers reported that they were satisfied or very satisfied with the newborn examination. Mothers assigned to a midwife were more satisfied with the newborn examination (crude odds ratio (OR) 0.54 (95% confidence interval (CI) 0.39 to 0.75), p < 0.001). However, after provision of health education during the examination, continuity of care provided, and history of miscarriage had been controlled for, status of examiner was no longer related to maternal satisfaction (adjusted OR 0.82 (95% CI 0.57–1.20), NS). The discussion of healthcare issues by the examiner (adjusted OR 0.49 (95% CI 0.34 to 0.70), p < 0.001) and continuity of care (adjusted OR 0.43 (95% CI 0.23 to 0.81), p < 0.01) were both related to enhanced satisfaction, and history of miscarriage (adjusted OR 1.61 (1.08 to 2.40), p < 0.05) was associated with lower maternal satisfaction with the newborn examination. Midwives (61%) were more likely than SHOs (33%) to discuss healthcare issues, such as feeding, sleeping, and skin care. Conclusions: Mothers were more likely to be satisfied with the newborn examination by a midwife than an SHO because midwives were more likely to discuss healthcare issues during the examination and were able to provide continuity of care. However, midwife examinations according to exclusion criteria agreed with trial midwives excluded half of all newborns, and criteria may have to be reconsidered for practice implementation. PMID:11978744

  17. Feasibility and effectiveness of a low cost campaign on antibiotic prescribing in Italy: community level, controlled, non-randomised trial

    PubMed Central

    Paltrinieri, Barbara; Marata, Anna Maria; Gagliotti, Carlo; Pan, Angelo; Moro, Maria Luisa; Capelli, Oreste; Magrini, Nicola

    2013-01-01

    Objectives To test the hypothesis that a multifaceted, local public campaign could be feasible and influence antibiotic prescribing for outpatients. Design Community level, controlled, non-randomised trial. Setting Provinces of Modena and Parma in Emilia-Romagna, northern Italy, November 2011 to February 2012. Population 1 150 000 residents of Modena and Parma (intervention group) and 3 250 000 residents in provinces in the same region but where no campaign had been implemented (control group). Interventions Campaign materials (mainly posters, brochures, and advertisements on local media, plus a newsletter on local antibiotic resistance targeted at doctors and pharmacists). General practitioners and paediatricians in the intervention area participated in designing the campaign messages. Main outcomes measures Primary outcome was the average change in prescribing rates of antibiotics for outpatient in five months, measured as defined daily doses per 1000 inhabitants/day, using health districts as the unit of analysis. Results Antibiotic prescribing was reduced in the intervention area compared with control area (−4.3%, 95% confidence interval −7.1% to −1.5%). This result was robust to “sensitivity analysis” modifying the baseline period from two months (main analysis) to one month. A higher decrease was observed for penicillins resistant to β lactamase and a lower decrease for penicillins susceptible to β lactamase, consistent with the content of the newsletter on antibiotic resistance directed at health professionals. The decrease in expenditure on antibiotics was not statistically significant in a district level analysis with a two month baseline period (main analysis), but was statistically significant in sensitivity analyses using either a one month baseline period or a more powered doctor level analysis. Knowledge and attitudes of the target population about the correct use of antibiotics did not differ between the intervention and control

  18. Effect of a lactation nurse on the success of breast-feeding: a randomised controlled trial.

    PubMed Central

    Jones, D A; West, R R

    1986-01-01

    An evaluation of a lactation nurse by means of a randomised controlled trial is described. The lactation nurse was employed to assist, support, and encourage mothers during the early weeks after parturition in hospital and at home. All mothers who breast-fed at least once were entered into the trial. Altogether 649 mothers were interviewed 12 months later to establish the duration of breast-feeding and to enquire after practices of and attitudes towards infant feeding. The lactation nurse significantly extended the duration of breast-feeding, particularly during the first four weeks and among women of lower social class. Although she did not reduce problems or change practices significantly, all the trends were consistently in the right direction. Mothers in the experimental group were more satisfied with the help they received than were mothers in the control group. It seems likely that the lactation nurse by consistent advice, assistance, support, and encouragement enabled mothers to cope more successfully with difficulties and that this led to significantly fewer ending breast-feeding prematurely. PMID:3519825

  19. A randomised controlled trial of sublingual misoprostol and intramuscular oxytocin for prevention of postpartum haemorrhage.

    PubMed

    Al-Sawaf, A; El-Mazny, A; Shohayeb, A

    2013-04-01

    This study aims to evaluate the efficacy and side-effects of 200 μg sublingual misoprostol vs 5 IU i.m. oxytocin, administered immediately following cord clamping in normal non-augmented vaginal delivery, in prevention of postpartum haemorrhage (PPH). A total of 104 women were randomised into three groups: misoprostol group (28 patients); oxytocin group (37 patients) and control group (39 patients). Misoprostol and oxytocin significantly minimised the blood loss during the third stage of labour and reduced the need for additional treatments for PPH as compared with the control group. Oxytocin was more effective than misoprostol in minimising blood loss and the need for additional uterotonic treatments. However, a significant decrease in systolic and diastolic blood pressure, associated with tachycardia was observed in the oxytocin group. In conclusion, sublingual misoprostol appears to be less effective than i.m. oxytocin in the prevention of PPH; however, it has the potential advantages of being easily used, cost-effective and stable at room temperature. Therefore, sublingual misoprostol is still a feasible drug for routine management of third stage, especially in areas with limited medical facilities.

  20. Randomised controlled trial of magnetic bracelets for relieving pain in osteoarthritis of the hip and knee

    PubMed Central

    Harlow, Tim; Greaves, Colin; White, Adrian; Brown, Liz; Hart, Anna; Ernst, Edzard

    2004-01-01

    Objective To determine the effectiveness of commercially available magnetic bracelets for pain control in osteoarthritis of the hip and knee. Design Randomised, placebo controlled trial with three parallel groups. Setting Five rural general practices. Participants 194 men and women aged 45-80 years with osteoarthritis of the hip or knee. Intervention Wearing a standard strength static bipolar magnetic bracelet, a weak magnetic bracelet, or a non-magnetic (dummy) bracelet for 12 weeks. Main outcome measures Change in the Western Ontario and McMaster Universities osteoarthritis lower limb pain scale (WOMAC A) after 12 weeks, with the primary comparison between the standard and dummy groups. Secondary outcomes included changes in WOMAC B and C scales and a visual analogue scale for pain. Results Mean pain scores were reduced more in the standard magnet group than in the dummy group (mean difference 1.3 points, 95% confidence interval 0.05 to 2.55). Self reported blinding status did not affect the results. The scores for secondary outcome measures were consistent with the WOMAC A scores. Conclusion Pain from osteoarthritis of the hip and knee decreases when wearing magnetic bracelets. It is uncertain whether this response is due to specific or non-specific (placebo) effects. PMID:15604181

  1. A Mediterranean Diet to Improve Cardiovascular and Cognitive Health: Protocol for a Randomised Controlled Intervention Study.

    PubMed

    Wade, Alexandra T; Davis, Courtney R; Dyer, Kathryn A; Hodgson, Jonathan M; Woodman, Richard J; Keage, Hannah A D; Murphy, Karen J

    2017-02-16

    The Mediterranean diet has demonstrated efficacy for improving cardiovascular and cognitive health. However, a traditional Mediterranean diet delivers fewer serves of dairy and less dietary calcium than is currently recommended in Australia, which may limit long-term sustainability. The present study aims to evaluate whether a Mediterranean diet with adequate dairy and calcium can improve cardiovascular and cognitive function in an at-risk population, and thereby reduce risk of cardiovascular disease (CVD) and cognitive decline. A randomised, controlled, parallel, crossover design trial will compare a Mediterranean diet supplemented with dairy foods against a low-fat control diet. Forty participants with systolic blood pressure above 120 mmHg and at least two other risk factors of CVD will undertake each dietary intervention for eight weeks, with an eight-week washout period between interventions. Systolic blood pressure will be the primary measure of interest. Secondary outcomes will include measures of cardiometabolic health, dietary compliance, cognitive function, assessed using the Cambridge Neuropsychological Test Automated Battery (CANTAB), psychological well-being and dementia risk. This research will provide empirical evidence as to whether the Mediterranean diet can be modified to provide recommended dairy and calcium intakes while continuing to deliver positive effects for cardiovascular and cognitive health. The findings will hold relevance for the field of preventative healthcare and may contribute to revisions of national dietary guidelines.

  2. Recovery of chronically lame dairy cows following treatment for claw horn lesions: a randomised controlled trial

    PubMed Central

    Thomas, H. J.; Remnant, J. G.; Bollard, N. J.; Burrows, A.; Whay, H. R.; Bell, N. J.; Mason, C.; Huxley, J. N.

    2016-01-01

    A positively controlled, randomised controlled trial (RCT) was undertaken to test recovery of cows with claw horn lesions resulting in lameness of greater than two weeks duration. Cows on seven commercial farms were mobility scored fortnightly and selected by lameness severity and chronicity. Study cows all received a therapeutic trim then random allocation of: no further treatment (trim only (TRM)), plastic shoe (TS) or plastic shoe and NSAID (TSN). Recovery was assessed by mobility score at 42 (±4) days post treatment by an observer blind to treatment group. Multivariable analysis showed no significant effect of treatment with an almost identical, low response rate to treatment across all groups (Percentage non-lame at outcome: TRM – 15 per cent, TS – 15 per cent, TSN – 16 per cent). When compared with results of a similar RCT on acutely lame cows, where response rates to treatment were substantially higher, it can be concluded that any delay in treatment is likely to reduce the rate of recovery, suggesting early identification and treatment is key. Thirty-eight per cent of animals treated in this study were lame on the contralateral limb at outcome suggesting that both hindlimbs should be examined and a preventive or if necessary a therapeutic foot trim performed when lameness is identified particularly if the duration of lameness is unknown. PMID:26811441

  3. Enhancing physical activity adherence and well-being in multiple sclerosis: a randomised controlled trial.

    PubMed

    McAuley, E; Motl, R W; Morris, K S; Hu, L; Doerksen, S E; Elavsky, S; Konopack, J F

    2007-06-01

    Individuals with multiple sclerosis (MS) are more sedentary than the general population, increasing their propensity for reduced functional ability, mobility, and activities of daily living. Self-efficacy has been one of the most consistent determinants of physical activity across populations, including those with MS. However, no studies exist that have attempted to influence self-efficacy in MS patients, in an effort to improve physical activity participation. We conducted a three-month randomised, controlled trial (n=26), contrasting the effects of an efficacy-enhancement exercise condition and a control exercise condition on exercise adherence, well-being, and affective responses to exercise. Analyses indicated that individuals in the efficacy enhancement condition attended more exercise sessions, reported greater levels of well-being and exertion, and felt better following exercise than individuals in the standard care condition. Regardless of treatment condition, individuals with a stronger sense of exercise self-efficacy, who reported more enjoyment following the exercise sessions, demonstrated significantly greater adherence with the exercise program. We believe this to be the first empirical attempt to change physical activity behavior in persons with MS using a well-established theoretical framework to drive the intervention. Continued examination of self-efficacy as a determinant of behavior change in individuals with MS is needed.

  4. Factors influencing hand washing behaviour in primary schools: process evaluation within a randomised controlled trial

    PubMed Central

    Chittleborough, Catherine R.; Nicholson, Alexandra L.; Basker, Elaine; Bell, Sarah; Campbell, Rona

    2013-01-01

    This paper explores factors that may influence hand washing behaviour among pupils and staff in primary schools. A qualitative process evaluation within a cluster randomised controlled trial included pupil focus groups (n=16, ages 6 to 11, semi-structured interviews (n=16 teachers) and observations of hand washing facilities (n=57). Pupils and staff in intervention and control schools demonstrated a similar level of understanding of how, when and why they should wash their hands. Lack of time, poor adult modelling of regular hand washing and unattractive facilities were seen as important barriers to regular hand washing. Reminders and explanations for the importance of hand hygiene were thought to have a positive impact. Influencing individual choices about hand washing through education and information may be necessary, but not sufficient, for initiating and maintaining good hand washing practices. Structural factors, including having time to wash hands using accessible, clean facilities, and being encouraged through the existence of hand washing opportunities in the daily routine and hand washing being viewed as the social norm, will also influence hand washing behaviour. The effectiveness of educational interventions at improving hand hygiene in primary schools may be improved by changing priorities of staff and increasing accessibility to quality facilities. PMID:22623617

  5. A Mediterranean Diet to Improve Cardiovascular and Cognitive Health: Protocol for a Randomised Controlled Intervention Study

    PubMed Central

    Wade, Alexandra T.; Davis, Courtney R.; Dyer, Kathryn A.; Hodgson, Jonathan M.; Woodman, Richard J.; Keage, Hannah A. D.; Murphy, Karen J.

    2017-01-01

    The Mediterranean diet has demonstrated efficacy for improving cardiovascular and cognitive health. However, a traditional Mediterranean diet delivers fewer serves of dairy and less dietary calcium than is currently recommended in Australia, which may limit long-term sustainability. The present study aims to evaluate whether a Mediterranean diet with adequate dairy and calcium can improve cardiovascular and cognitive function in an at-risk population, and thereby reduce risk of cardiovascular disease (CVD) and cognitive decline. A randomised, controlled, parallel, crossover design trial will compare a Mediterranean diet supplemented with dairy foods against a low-fat control diet. Forty participants with systolic blood pressure above 120 mmHg and at least two other risk factors of CVD will undertake each dietary intervention for eight weeks, with an eight-week washout period between interventions. Systolic blood pressure will be the primary measure of interest. Secondary outcomes will include measures of cardiometabolic health, dietary compliance, cognitive function, assessed using the Cambridge Neuropsychological Test Automated Battery (CANTAB), psychological well-being and dementia risk. This research will provide empirical evidence as to whether the Mediterranean diet can be modified to provide recommended dairy and calcium intakes while continuing to deliver positive effects for cardiovascular and cognitive health. The findings will hold relevance for the field of preventative healthcare and may contribute to revisions of national dietary guidelines. PMID:28212320

  6. Eating disinhibition and vagal tone moderate the postprandial response to glycemic load: a randomised controlled trial

    PubMed Central

    Young, Hayley A.; Watkins, Heather

    2016-01-01

    Reducing the glycemic load (GL) of the diet may benefit appetite control but its utility is complicated by psychological influences on eating. Disinhibited behaviour, a risk factor for overconsumption, is characterized by reduced prefrontal cortex activity, which in turn modulates vagal tone; a phenomenon associated with glucoregulation. This double blind randomised controlled trial explored for the first time the influence of disinhibited eating and vagal tone (heart rate variability (HRV)) on hunger and the postprandial response to GL. Blood glucose (BG) and hunger were measured 30 and 150 min after consumption of water, glucose or isomaltulose (low glycemic sugar). After consuming glucose, independently of BMI or habitual diet, those with the highest levels of disinhibition had higher BG levels after thirty minutes (B = 0.192, 95% CI LL. 086, UL 0.297), and lower BG after one hundred and fifty minutes (B = −0.240, 95% CI LL −0.348, UL −0.131). BG was related to hunger but only in low disinhibited eaters. Disinhibited eaters were characterised by a reduced HRV which was related to greater BG excursions (B = 0.407, 95% CI LL 0.044, UL 1.134). These findings highlight novel mechanisms by which disinhibited eating leads to obesity and insulin resistance. This trial was registered at clinicaltrials.gov NCT02827318. PMID:27761024

  7. Cognitive stimulation for dementia: a systematic review of the evidence of effectiveness from randomised controlled trials.

    PubMed

    Aguirre, Elisa; Woods, Robert T; Spector, Aimee; Orrell, Martin

    2013-01-01

    Cognitive stimulation is a psychological intervention widely used in dementia care, which offers a range of activities for people with dementia and provides general stimulation of cognitive abilities. This systematic review evaluates the effectiveness of cognitive stimulation in dementia. The review included studies from the Specialized Register of the Cochrane Dementia and Cognitive Improvement Group, called ALOIS. This yielded ninety-four studies, of which fifteen were randomised controlled trials meeting the inclusion criteria. The analysis included 718 subjects (407 receiving cognitive stimulation and 311 in control groups). Results were subjected to a meta-analysis. A consistent significant benefit to cognitive function was identified following treatment and the benefits appeared to be over and above any medication effects. This remained evident at follow-up up to three months after the end of treatment. In secondary analyses, with smaller total sample sizes, significant benefits were also noted for quality of life and well-being, and on staff ratings of communication and social interaction. No differences in relation to mood, activities of daily living or challenging behaviour were noted. There is consistent evidence that cognitive stimulation interventions benefit cognitive function and aspects of well-being. Cognitive stimulation should be made more widely available in dementia care.

  8. Acupuncture for the Treatment of Oculomotor Paralysis: A Pilot Randomised Controlled Trial

    PubMed Central

    Bi, Jia-Qi; Li, Wei; Yang, Qi; Li, Bao-lin; Meng, Qing-Gang; Liu, Yu-fu

    2016-01-01

    This study consisted of a single centre randomised controlled trial with two parallel arms: an acupuncture group (n = 20) with 27 affected eyes and a sham group (n = 20) with 23 affected eyes. Participants in the acupuncture group received acupuncture treatment once daily, three times weekly for four weeks. Participants assigned to the control group received sham acupuncture, the same protocol as that used for the acupuncture group but without insertion of needles into the skin. The primary outcome measure was the cervical range of motion (CROM) score. Secondary outcome measures were the palpebral fissure size, response rate, and adverse events. All 40 participants completed the study. In the comparison of acupuncture and sham acupuncture, a significant difference was observed between acupuncture and sham acupuncture in CROM score (21.37 ± 15.16 and 32.21 ± 19.54, resp.) (P < 0.05) and palpebral fissure size (7.19 ± 2.94 and 5.41 ± 2.45, resp.) (P < 0.05). Response rate was also significantly different in the acupuncture group (P < 0.05). No adverse events were reported in both groups in this study. In summary, it was demonstrated that acupuncture had a feasibility positive effect on oculomotor paralysis. PMID:27313646

  9. Efficacy of acupunture in patients with chronic neck pain--a randomised, sham controlled trial.

    PubMed

    Sahin, Nilay; Ozcan, Emel; Sezen, Kasim; Karatas, Omer; Issever, Halim

    2010-01-01

    The aim of this study was to compare the efficacy of electroacupuncture and sham acupuncture in the treatment of patients with chronic neck pain. 31 patients with chronic neck pain were included in a randomised, controlled trial. Electric stimulation was given for 30 minutes at low frequency (1-4Hz), pulse width of 200 micros, interrupted wave form. Of the 29 patients who completed the therapy, 13 were assigned to conventional acupuncture and 16 to sham acupuncture groups, receiving 3 sessions a week for a total of 10 sessions, each lasting for 30 minutes. Patients were evaluated before and after therapy and 3 months later by Visual Analogue Scale (VAS) and the bodily pain subscale of the Short Form Health Survey-36 scale. The treating physician was different from the evaluating physician who, like the patient, was blinded. VAS scores in both groups significantly reduced after therapy and at 3 months post-therapy, but the difference between groups was not significant. In respect of bodily pain, there was a significant improvement in the acupuncture group after therapy (P<0.01). Stimulation of conventional acupuncture points was not generally superior to needling ofnonspecific points on the neck, and both treatments were associated with improvement of symptoms. Needles inserted into the neck are likely to be an inappropriate sham control for acupuncture.

  10. Randomised controlled trial of graded exercise in patients with the chronic fatigue syndrome.

    PubMed Central

    Fulcher, K. Y.; White, P. D.

    1997-01-01

    OBJECTIVE: To test the efficacy of a graded aerobic exercise programme in the chronic fatigue syndrome. DESIGN: Randomised controlled trial with control treatment crossover after the first follow up examination. SETTING: Chronic fatigue clinic in a general hospital department of psychiatry. SUBJECTS: 66 patients with the chronic fatigue syndrome who had neither a psychiatric disorder nor appreciable sleep disturbance. INTERVENTIONS: Random allocation to 12 weeks of either graded aerobic exercise or flexibility exercises and relaxation therapy. Patients who completed the flexibility programme were invited to cross over to the exercise programme afterwards. MAIN OUTCOME MEASURE: The self rated clinical global impression change score, "very much better" or "much better" being considered as clinically important. RESULTS: Four patients receiving exercise and three receiving flexibility treatment dropped out before completion. 15 of 29 patients rated themselves as better after completing exercise treatment compared with eight of 30 patients who completed flexibility treatment. Analysis by intention to treat gave similar results (17/33 v 9/33 patients better). Fatigue, functional capacity, and fitness were significantly better after exercise than after flexibility treatment. 12 of 22 patients who crossed over to exercise after flexibility treatment rated themselves as better after completing exercise treatment 32 of 47 patients rated themselves as better three months after completing supervised exercise treatment 35 of 47 patients rated themselves as better one year after completing supervised exercise treatment. CONCLUSION: These findings support the use of appropriately prescribed graded aerobic exercise in the management of patients with the chronic fatigue syndrome. PMID:9180065

  11. Randomised placebo-controlled trials of surgery: ethical analysis and guidelines

    PubMed Central

    Savulescu, Julian; Wartolowska, Karolina; Carr, Andy

    2016-01-01

    Use of a placebo control in surgical trials is a divisive issue. We argue that, in principle, placebo controls for surgery are necessary in the same way as for medicine. However, there are important differences between these types of trial, which both increase justification and limit application of surgical studies. We propose that surgical randomised placebo-controlled trials are ethical if certain conditions are fulfilled: (1) the presence of equipoise, defined as a lack of unbiased evidence for efficacy of an intervention; (2) clinically important research question; (3) the risk to patients is minimised and reasonable; (4) there is uncertainty about treatment allocation rather than deception; (5) there is preliminary evidence for efficacy, which justifies a placebo-controlled design; and (6) ideally, the placebo procedure should have some direct benefit to the patient, for example, as a diagnostic tool. Placebo-controlled trials in surgery will most often be justified when surgery is performed to improve function or relieve symptoms and when objective outcomes are not available, while the risk of mortality or significant morbidity is low. In line with medical placebo-controlled trials, the surgical trial (1) should be sufficiently powered and (2) standardised so that its results are valid, (3) consent should be valid, (4) the standard treatment or rescue medication should be provided if possible, and (5) after the trial, the patients should be told which treatment they received and there should be provision for post-trial care if the study may result in long-term negative effects. We comment and contrast our guidelines with those of the American Medical Association. PMID:27777269

  12. Computer-assisted orthognathic surgery for correction of facial asymmetry: results of a randomised controlled clinical trial.

    PubMed

    De Riu, Giacomo; Meloni, Silvio Mario; Baj, Alessandro; Corda, Andrea; Soma, Damiano; Tullio, Antonio

    2014-03-01

    In this randomised controlled clinical trial, 2 homogeneous groups of patients with facial asymmetry (n=10 in each) were treated by either classic or computer-assisted orthognathic corrective surgery. Differences between the 2 groups in the alignment of the lower interincisal point (p=0.03), mandibular sagittal plane (p=0.01), and centering of the dental midlines (p=0.03) were significant, with the digital planning group being more accurate.

  13. Robust control of underactuated manipulators: Analysis and implementation

    NASA Astrophysics Data System (ADS)

    Bergerman, Marcel; Xu, Yangsheng

    1994-05-01

    Underactuated manipulators are robot manipulators composed of both active and passive joints. The advantages of using such systems reside in the fact that they weigh less and consume less energy than their fully-actuated counterparts, thus being useful for applications such as space robotics. Another interest resides in the reliability or fault-tolerant design of fully-actuated manipulators. If any of the joint actuators of such a device fails, an entire operation may have to be aborted because of the loss of one or more degrees of freedom. The methodology proposed in this paper uses the dynamic coupling between the passive joints and the active joints, and controls the active ones in order to bring the passive joint angles to a desired set-point. Therefore, the control law and the performance of the system are completely dependent on the dynamic model. Since it is difficult to obtain the exact dynamic model of the system in general, considerable position errors and even instability can result in some cases. In this paper, we propose a variable structure controller to provide the system with the robustness necessary to perform tasks regardless of the modelling errors. Case studies are provided as a means of illustration.

  14. Robustness and control of a magnetically levitated transportation system

    NASA Astrophysics Data System (ADS)

    Oleszczuk, Grzegorz

    2006-04-01

    Electromagnetic suspension of Magnetic Levitation Vehicles (Maglev) has been studied for many years as an alternative to wheel-on rail transportation systems. In this work, design and implementation of control systems for a Maglev laboratory experiment and a Maglev vehicle under development at Old Dominion University are described. Both plants are modeled and simulated with consideration of issues associated with system non-linearity, structural flexibility and electromagnetic force modeling. Discussion concerning different control strategies, namely centralized and decentralized approaches are compared and contrasted in this work. Different types of electromagnetic non-linearities are considered and described to establish a convenient method for modeling such a system. It is shown how a Finite Element structural model can be incorporated into the system to obtain transfer function notation. Influence of the dynamic interaction between the Maglev track and the Maglev vehicle is discussed and supported by both analytical results and theoretical examples. Finally, several control laws designed to obtain stable and robust levitation are explored in detail.

  15. Robust, Flexible Motion Control for the Mars Explorer Rovers

    NASA Technical Reports Server (NTRS)

    Maimone, Mark; Biesiadecki, Jeffrey

    2007-01-01

    The Mobility Flight Software, running on computers aboard the Mars Explorer Rover (MER) robotic vehicles Spirit and Opportunity, affords the robustness and flexibility of control to enable safe and effective operation of these vehicles in traversing natural terrain. It can make the vehicles perform specific maneuvers commanded from Earth, and/or can autonomously administer multiple aspects of mobility, including choice of motion, measurement of actual motion, and even selection of targets to be approached. Motion of a vehicle can be commanded by use of multiple layers of control, ranging from motor control at a low level, direct drive operations (e.g., motion along a circular arc, motion along a straight line, or turn in place) at an intermediate level to goal-position driving (that is, driving to a specified location) at a high level. The software can also perform high-level assessment of terrain and selection of safe paths across the terrain: this involves processing of the digital equivalent of a local traversability map generated from images acquired by stereoscopic pairs of cameras aboard the vehicles. Other functions of the software include interacting with the rest of the MER flight software and performing safety checks.

  16. Robust Task Space Trajectory Tracking Control of Robotic Manipulators

    NASA Astrophysics Data System (ADS)

    Galicki, M.

    2016-08-01

    This work deals with the problem of the accurate task space trajectory tracking subject to finite-time convergence. Kinematic and dynamic equations of a redundant manipulator are assumed to be uncertain. Moreover, globally unbounded disturbances are allowed to act on the manipulator when tracking the trajectory by the end-effector. Furthermore, the movement is to be accomplished in such a way as to reduce both the manipulator torques and their oscillations thus eliminating the potential robot vibrations. Based on suitably defined task space non-singular terminal sliding vector variable and the Lyapunov stability theory, we propose a class of chattering-free robust controllers, based on the estimation of transpose Jacobian, which seem to be effective in counteracting both uncertain kinematics and dynamics, unbounded disturbances and (possible) kinematic and/or algorithmic singularities met on the robot trajectory. The numerical simulations carried out for a redundant manipulator of a SCARA type consisting of the three revolute kinematic pairs and operating in a two-dimensional task space, illustrate performance of the proposed controllers as well as comparisons with other well known control schemes.

  17. A pragmatic multi-centred randomised controlled trial of yoga for chronic low back pain: Trial protocol

    PubMed Central

    Cox, Helen; Tilbrook, Helen; Aplin, John; Chuang, Ling-Hsiang; Hewitt, Catherine; Jayakody, Shalmini; Semlyen, Anna; Soares, Marta O.; Torgerson, David; Trewhela, Alison; Watt, Ian; Worthy, Gill

    2010-01-01

    A systematic review revealed three small randomised controlled trials of yoga for low back pain, all of which showed effects on back pain that favoured the yoga group. To build on these studies a larger trial, with longer term follow-up, and a number of different yoga teachers delivering the intervention is required. This study protocol describes the details of a randomised controlled trial (RCT) to determine the effectiveness and cost-effectiveness of Yoga for chronic Low Back Pain, which is funded by Arthritis Research Campaign (arc) and is being conducted by the University of York. 262 patients will be recruited from GP practices in 5 centres in England. Patients will be randomised to receive usual care or 12 weekly classes of yoga. A yoga programme will be devised that can be delivered by yoga teachers of the two main national yoga organisations in the UK (British Wheel of Yoga and Iyengar Yoga Association (UK)). Trial registration: Current controlled trials registry ISRCTN81079604 (date registered 30/03/2007). PMID:20347837

  18. A randomised controlled trial of tiotropium in adolescents with severe symptomatic asthma

    PubMed Central

    Bernstein, Jonathan A.; Vandewalker, Mark; Moroni-Zentgraf, Petra; Verri, Daniela; Unseld, Anna; Engel, Michael; Boner, Attilio L.

    2017-01-01

    We present results from the first phase III trial of once-daily tiotropium add-on to inhaled corticosteroids (ICS) plus one or more controller therapies in adolescents with severe symptomatic asthma. In this double-blind, parallel-group trial (NCT01277523), 392 patients aged 12–17 years were randomised to receive once-daily tiotropium 5 µg or 2.5 µg, or placebo, as an add-on to ICS plus other controller therapies over 12 weeks. The primary and key secondary end-points were change from baseline (response) in peak forced expiratory volume in 1 s (FEV1) within 3 h post-dosing (FEV1(0–3h)) and trough FEV1, respectively, after 12 weeks of treatment. Tiotropium 5 µg provided numerical improvements in peak FEV1(0–3h) response, compared with placebo (90 mL; p=0.104), and significant improvements were observed with tiotropium 2.5 µg (111 mL; p=0.046). Numerical improvements in trough FEV1 response and asthma control were observed with both tiotropium doses, compared with placebo. The safety and tolerability of tiotropium were comparable with those of placebo. Once-daily tiotropium Respimat add-on to ICS plus one or more controller therapies in adolescents with severe symptomatic asthma was well tolerated. The primary end-point of efficacy was not met, although positive trends for improvements in lung function and asthma control were observed. PMID:27811070

  19. A randomised control study of a fully automated internet based smoking cessation programme

    PubMed Central

    Swartz, L H G; Noell, J W; Schroeder, S W; Ary, D V

    2006-01-01

    Objective The objective of this project was to test the short term (90 days) efficacy of an automated behavioural intervention for smoking cessation, the “1‐2‐3 Smokefree” programme, delivered via an internet website. Design Randomised control trial. Subjects surveyed at baseline, immediately post‐intervention, and 90 days later. Settings The study and the intervention occurred entirely via the internet site. Subjects were recruited primarily via worksites, which referred potential subjects to the website. Subjects The 351 qualifying subjects were notified of the study via their worksite and required to have internet access. Additionally, subjects were required to be over 18 years of age, smoke cigarettes, and be interested in quitting smoking in the next 30 days. Eligible subjects were randomly assigned individually to treatment or control condition by computer algorithm. Intervention The intervention consisted of a video based internet site that presented current strategies for smoking cessation and motivational materials tailored to the user's race/ethnicity, sex, and age. Control subjects received nothing for 90 days and were then allowed access to the programme. Main outcome measures The primary outcome measure was abstinence from smoking at 90 day follow up. Results At follow up, the cessation rate at 90 days was 24.1% (n  =  21) for the treatment group and 8.2% (n  =  9) for the control group (p  =  0.002). Using an intent‐to‐treat model, 12.3% (n  =  21) of the treatment group were abstinent, compared to 5.0% (n  =  9) in the control group (p  =  0.015). Conclusions These evaluation results suggest that a smoking cessation programme, with at least short term efficacy, can be successfully delivered via the internet. PMID:16436397

  20. The impact of the Virtual Ophthalmology Clinic on medical students' learning: a randomised controlled trial

    PubMed Central

    Succar, T; Zebington, G; Billson, F; Byth, K; Barrie, S; McCluskey, P; Grigg, J

    2013-01-01

    Aim The Virtual Ophthalmology Clinic (VOC) is an interactive web-based teaching module, with special emphasis on history taking and clinical reasoning skills. The purpose of this study was to determine the impact of VOC on medical students' learning. Methods A randomised controlled trial (RCT) was conducted with medical students from the University of Sydney (n=188) who were randomly assigned into either an experimental (n=93) or a control group (n=95). A pre- and post-test and student satisfaction questionnaire were administered. Twelve months later a follow-up test was conducted to determine the long-term retention rate of graduates. Results There was a statistically significant (P<0.001) within-subject improvement pre- to post rotation in the number of correctly answered questions for both the control and experimental groups (mean improvement for control 10%, 95% CI 1.3–2.6, and for experimental 17.5%, 95% CI 3.0–4.0). The improvement was significantly greater in the experimental group (mean difference in improvement between groups 7.5%, 95% CI 0.8–2.3, P<0.001). At 12 months follow-up testing, the experimental group scored on average 1.6 (8%) (95%CI 0.4 to 2.7, P=0.007) higher than the controls. Conclusion On the basis of a statistically significant improvement in academic performance and highly positive student feedback, the implementation of VOC may provide a means to address challenges to ophthalmic learning outcomes in an already crowded medical curriculum. PMID:23867718

  1. A novel school-based intervention to improve nutrition knowledge in children: cluster randomised controlled trial

    PubMed Central

    2010-01-01

    Background Improving nutrition knowledge among children may help them to make healthier food choices. The aim of this study was to assess the effectiveness and acceptability of a novel educational intervention to increase nutrition knowledge among primary school children. Methods We developed a card game 'Top Grub' and a 'healthy eating' curriculum for use in primary schools. Thirty-eight state primary schools comprising 2519 children in years 5 and 6 (aged 9-11 years) were recruited in a pragmatic cluster randomised controlled trial. The main outcome measures were change in nutrition knowledge scores, attitudes to healthy eating and acceptability of the intervention by children and teachers. Results Twelve intervention and 13 control schools (comprising 1133 children) completed the trial. The main reason for non-completion was time pressure of the school curriculum. Mean total nutrition knowledge score increased by 1.1 in intervention (baseline to follow-up: 28.3 to 29.2) and 0.3 in control schools (27.3 to 27.6). Total nutrition knowledge score at follow-up, adjusted for baseline score, deprivation, and school size, was higher in intervention than in control schools (mean difference = 1.1; 95% CI: 0.05 to 2.16; p = 0.042). At follow-up, more children in the intervention schools said they 'are currently eating a healthy diet' (39.6%) or 'would try to eat a healthy diet' (35.7%) than in control schools (34.4% and 31.7% respectively; chi-square test p < 0.001). Most children (75.5%) enjoyed playing the game and teachers considered it a useful resource. Conclusions The 'Top Grub' card game facilitated the enjoyable delivery of nutrition education in a sample of UK primary school age children. Further studies should determine whether improvements in nutrition knowledge are sustained and lead to changes in dietary behaviour. PMID:20219104

  2. A randomised controlled trial of tiotropium in adolescents with severe symptomatic asthma.

    PubMed

    Hamelmann, Eckard; Bernstein, Jonathan A; Vandewalker, Mark; Moroni-Zentgraf, Petra; Verri, Daniela; Unseld, Anna; Engel, Michael; Boner, Attilio L

    2017-01-01

    We present results from the first phase III trial of once-daily tiotropium add-on to inhaled corticosteroids (ICS) plus one or more controller therapies in adolescents with severe symptomatic asthma.In this double-blind, parallel-group trial (NCT01277523), 392 patients aged 12-17 years were randomised to receive once-daily tiotropium 5 µg or 2.5 µg, or placebo, as an add-on to ICS plus other controller therapies over 12 weeks. The primary and key secondary end-points were change from baseline (response) in peak forced expiratory volume in 1 s (FEV1) within 3 h post-dosing (FEV1(0-3h)) and trough FEV1, respectively, after 12 weeks of treatment.Tiotropium 5 µg provided numerical improvements in peak FEV1(0-3h) response, compared with placebo (90 mL; p=0.104), and significant improvements were observed with tiotropium 2.5 µg (111 mL; p=0.046). Numerical improvements in trough FEV1 response and asthma control were observed with both tiotropium doses, compared with placebo. The safety and tolerability of tiotropium were comparable with those of placebo.Once-daily tiotropium Respimat add-on to ICS plus one or more controller therapies in adolescents with severe symptomatic asthma was well tolerated. The primary end-point of efficacy was not met, although positive trends for improvements in lung function and asthma control were observed.

  3. A pilot randomised controlled trial of negative pressure wound therapy to treat grade III/IV pressure ulcers [ISRCTN69032034

    PubMed Central

    2012-01-01

    Background Negative pressure wound therapy (NPWT) is widely promoted as a treatment for full thickness wounds; however, there is a lack of high-quality research evidence regarding its clinical and cost effectiveness. A trial of NPWT for the treatment of grade III/IV pressure ulcers would be worthwhile but premature without assessing whether such a trial is feasible. The aim of this pilot randomised controlled trial was to assess the feasibility of conducting a future full trial of NPWT for the treatment of grade III and IV pressure ulcers and to pilot all aspects of the trial. Methods This was a two-centre (acute and community), pilot randomised controlled trial. Eligible participants were randomised to receive either NPWT or standard care (SC) (spun hydrocolloid, alginate or foam dressings). Outcome measures were time to healing of the reference pressure ulcer, recruitment rates, frequency of treatment visits, resources used and duration of follow-up. Results Three hundred and twelve patients were screened for eligibility into this trial over a 12-month recruitment period and 12/312 participants (3.8%) were randomised: 6 to NPWT and 6 to SC. Only one reference pressure ulcer healed (NPWT group) during follow-up (time to healing 79 days). The mean number of treatment visits per week was 3.1 (NPWT) and 5.7 (SC); 6/6 NPWT and 1/6 SC participants withdrew from their allocated trial treatment. The mean duration of follow-up was 3.8 (NPWT) and 5.0 (SC) months. Conclusions This pilot trial yielded vital information for the planning of a future full study including projected recruitment rate, required duration of follow-up and extent of research nurse support required. Data were also used to inform the cost-effectiveness and value of information analyses, which were conducted alongside the pilot trial. Trial registration Current Controlled Trials ISRCTN69032034. PMID:22839453

  4. Robust ?dynamic output feedback control of networked control systems with congestion control

    NASA Astrophysics Data System (ADS)

    Rasool, Faiz; Kiong Ngaung, Sing

    2015-07-01

    This paper investigates a robust ?dynamic output feedback controller for networked control systems (NCSs) with a simple congestion control scheme. This scheme enables the NCSs design to enjoy advantages of both time-triggered and event-triggered systems. The proposed scheme compares current measurement with last transmitted measurement. If difference between them is less than a prescribed percentage of the current measurements then no measurement is transmitted to controller and the controller always uses the last transmitted measurements to calculate feedback gains. Moreover, this technique is applied to controller output as well. The stability criteria for closed-loop system is formulated using the Lyapunov-Krasovskii functional approach. The sufficient conditions for the controller are given in terms of solvability of bilinear matrix inequalities (BMIs). These BMIs are converted into quasi-convex linear matrix inequalities that are solved using the cone complementarity linearisation algorithm. A simulation example is used to evaluate how effective the simple congestion control scheme is in reducing network bandwidth.

  5. Cost-effectiveness of telehealth for patients with depression: evidence from the Healthlines randomised controlled trial

    PubMed Central

    Hollinghurst, Sandra; Edwards, Louisa; Thomas, Clare; Foster, Alexis; Davies, Ben; Gaunt, Daisy; Montgomery, Alan A.; Salisbury, Chris

    2016-01-01

    Background Depression is a prevalent long-term condition that is associated with substantial resource use. Telehealth may offer a cost-effective means of supporting the management of people with depression. Aims To investigate the cost-effectiveness of a telehealth intervention (‘Healthlines') for patients with depression. Method A prospective patient-level economic evaluation conducted alongside a randomised controlled trial. Patients were recruited through primary care, and the intervention was delivered via a telehealth service. Participants with a confirmed diagnosis of depression and PHQ-9 score ≥10 were recruited from 43 English general practices. A series of up to 10 scripted, theory-led, telephone encounters with health information advisers supported participants to effect a behaviour change, use online resources, optimise medication and improve adherence. The intervention was delivered alongside usual care and was designed to support rather than duplicate primary care. Cost-effectiveness from a combined health and social care perspective was measured by net monetary benefit at the end of 12 months of follow-up, calculated from incremental cost and incremental quality-adjusted life years (QALYs). Cost–consequence analysis included cost of lost productivity, participant out-of-pocket expenditure and the clinical outcome. Results A total of 609 participants were randomised – 307 to receive the Healthlines intervention plus usual care and 302 to receive usual care alone. Forty-five per cent of participants had missing quality of life data, 41% had missing cost data and 51% of participants had missing data on either cost or utility, or both. Multiple imputation was used for the base-case analysis. The intervention was associated with incremental mean per-patient National Health Service/personal social services cost of £168 (95% CI £43 to £294) and an incremental QALY gain of 0.001 (95% CI −0.023 to 0.026). The incremental cost-effectiveness ratio

  6. Comparison of a minimally invasive procedure versus standard microscopic discotomy: a prospective randomised controlled clinical trial

    PubMed Central

    Greiner-Perth, R.; Boehm, H.; Mahlfeld, K.; Grasshoff, H.; Allam, Y.; Awiszus, F.

    2009-01-01

    A Prospective randomised controlled study was done to determine statistical difference between the standard microsurgical discotomy (MC) and a minimally invasive microscopic procedure for disc prolapse surgery by comparing operation duration and clinical outcome. Additionally, the transferability of the results was determined by a bicentric design. The microscopic assisted percutaneous nucleotomy (MAPN) has been advocated as a minimally invasive tubular technique. Proponents have claimed that minimally invasive procedures reduce postoperative pain and accelerate the recovery. In addition, there exist only a limited number of well-designed comparison studies comparing standard microdiscotomy to a tubular minimally invasive technique that support this claim. Furthermore, there are no well-designed studies looking at the transferability of those results and possible learning curve phenomena. We studied 100 patients, who were planned for disc prolapse surgery at two centres [50 patients at the developing centre (index) and 50 patients at the less experienced (transfer) centre]. The randomisation was done separately for each centre, employing a block-randomisation procedure with respect to age and preoperative Oswestry score. Operation duration was chosen as a primary outcome parameter as there was a distinguished shortening observed in a preliminary study at the index centre enabling a sound case number estimation. The following data were compared between the two groups and the centres with a 12-month follow-up: surgical times (operation duration and approach duration), the clinical results, leg and back pain by visual analogue scale, the Oswestry disability index, length of hospital stay, return to work time, and complications. The operation duration was statistically identical for MC (57.8 ± 20.2 min) at the index centre and for MAPN (50.3 ± 18.3 min) and MC (54.7 ± 18.1 min) at the transfer centre. The operation duration was only significantly shorter

  7. Oral misoprostol for induction of labour at term: randomised controlled trial

    PubMed Central

    Dodd, Jodie M; Crowther, Caroline A; Robinson, Jeffrey S

    2006-01-01

    Objective To compare oral misoprostol solution with vaginal prostaglandin gel (dinoprostone) for induction of labour at term to determine whether misoprostol is superior. Design Randomised double blind placebo controlled trial. Setting Maternity departments in three hospitals in Australia. Population Pregnant women with a singleton cephalic presentation at ≥ 36+6 weeks' gestation, with an indication for prostaglandin induction of labour. Interventions 20 μg oral misoprostol solution at ourly intervals and placebo vaginal gel or vaginal dinoprostone gel at six hourly intervals and placebo oral solution. Main outcome measures Vaginal birth within 24 hours; uterine hyperstimulation with associated changes in fetal heart rate; caesarean section (all); and caesarean section for fetal distress. Results 741 women were randomised, 365 to the misoprostol group and 376 to the vaginal dinoprostone group. There were no significant differences between the two treatment groups in the primary outcomes: vaginal birth not achieved in 24 hours (misoprostol 168/365 (46.0%) v dinoprostone 155/376 (41.2%); relative risk 1.12, 95% confidence interval 0.95 to 1.32; P = 0.134), caesarean section (83/365 (22.7%) v 100/376 (26.6%); 0.82, 0.64 to 1.06; P = 0.127), caesarean section for fetal distress (32/365 (8.8%) v 35/376 (9.3%); 0.91, 0.57 to 1.44; P = 0.679), or uterine hyperstimulation with changes in fetal heart rate (3/365 (0.8%) v 6/376 (1.6%); 0.55, 0.14 to 2.21; P = 0.401). Although there were differences in the process of labour induction, there were no significant differences in adverse maternal or neonatal outcomes. Conclusions This trial shows no evidence that oral misoprostol is superior to vaginal dinoprostone for induction of labour. However, it does not lead to poorer health outcomes for women or their infants, and oral treatment is preferred by women. Trial registration National Health and Medical Research Council, Perinatal Trials, PT0361. PMID:16455695

  8. Tactile acuity training for patients with chronic low back pain: a pilot randomised controlled trial

    PubMed Central

    2014-01-01

    Background Chronic pain can disrupt the cortical representation of a painful body part. This disruption may play a role in maintaining the individual’s pain. Tactile acuity training has been used to normalise cortical representation and reduce pain in certain pain conditions. However, there is little evidence for the effectiveness of this intervention for chronic low back pain (CLBP). The primary aim of this study was to inform the development of a fully powered randomised controlled trial (RCT) by providing preliminary data on the effect of tactile acuity training on pain and function in individuals with CLBP. The secondary aim was to obtain qualitative feedback about the intervention. Methods In this mixed-methods pilot RCT 15 individuals were randomised to either an intervention (tactile acuity training) or a placebo group (sham tactile acuity training). All participants received 3 sessions of acuity training (intervention or sham) from a physiotherapist and were requested to undertake daily acuity home training facilitated by an informal carer (friend/relative). All participants also received usual care physiotherapy. The primary outcome measures were pain (0-100visual analogue scale (VAS)) and function (Roland Morris Disability Questionnaire (RMDQ)). Participants and their informal carers were invited to a focus group to provide feedback on the intervention. Results The placebo group improved by the greatest magnitude for both outcome measures, but there was no statistically significant difference (Mean difference (95%CI), p-value) between groups for change in pain (25.6 (-0.7 to 51.9), p = 0.056) or function (2.2 (-1.6 to 6.0), p = 0.237). Comparing the number of individuals achieving a minimally clinically significant improvement, the placebo group had better outcomes for pain with all participants achieving ≥30% improvement compared to only a third of the intervention group (6/6 vs. 3/9, p = 0.036). Qualitatively, participants reported that

  9. Clinical outcomes of Single-Visit oral Prophylaxis: A practice-based randomised controlled trial

    PubMed Central

    2011-01-01

    Background Practice-based general dental practitioners routinely provide "scale and polish" or "oral prophylaxis" to patients attending their practices. Despite its routine provision, there is no evidence to support the clinical effectiveness of single-visit scale and polish, nor the frequency at which it should be provided. A recent systematic review recommended that future trials investigating scale and polish should involve dental practice patients. Methods A practice-based parallel randomised controlled trial with 24-month follow-up was conducted. Healthy adults (Basic Periodontal Examination [BPE] codes <3) were randomly assigned to 3 groups (6-month, 12-month, or 24-month interval between scale and polish). The primary outcome was gingival bleeding with the hypothesis that 6-monthly scale and polish would result in lower prevalence than 12-month or 24-month frequency. Follow-up measurements were recorded by examiners blinded to the allocation. 125, 122 and 122 participants were randomised to the 6-month, 12-month and 24-month groups respectively. Complete data set analyses were conducted for 307 participants: 107, 100, and 100 in the 6-month, 12-month and 24-month groups respectively. Chi-square test and ANOVA were used to compare treatment groups at follow-up. Logistic regression and ANCOVA were used to estimate the relationship between outcome and treatment group, adjusted for baseline values. Multiple imputation analyses were also carried out for participants with incomplete data sets. Results Prevalence of gingival bleeding at follow-up was 78.5% (6-month), 78% (12-month) and 82% (24-month) (p = 0.746). There were no statistically significant differences between groups with respect to follow-up prevalence of plaque and calculus. Statistically significant differences detected in the amount (millimetres) of calculus were too small to be clinically significant. Seventeen (4.6%) participants were withdrawn from the trial to receive additional treatment

  10. Endovascular therapy for acute ischaemic stroke: the Pragmatic Ischaemic Stroke Thrombectomy Evaluation (PISTE) randomised, controlled trial

    PubMed Central

    Muir, Keith W; Ford, Gary A; Messow, Claudia-Martina; Ford, Ian; Murray, Alicia; Clifton, Andrew; Brown, Martin M; Madigan, Jeremy; Lenthall, Rob; Robertson, Fergus; Dixit, Anand; Cloud, Geoffrey C; Wardlaw, Joanna; Freeman, Janet; White, Philip

    2017-01-01

    Objective The Pragmatic Ischaemic Thrombectomy Evaluation (PISTE) trial was a multicentre, randomised, controlled clinical trial comparing intravenous thrombolysis (IVT) alone with IVT and adjunctive intra-arterial mechanical thrombectomy (MT) in patients who had acute ischaemic stroke with large artery occlusive anterior circulation stroke confirmed on CT angiography (CTA). Design Eligible patients had IVT started within 4.5 hours of stroke symptom onset. Those randomised to additional MT underwent thrombectomy using any Conformité Européene (CE)-marked device, with target interval times for IVT start to arterial puncture of <90 min. The primary outcome was the proportion of patients achieving independence defined by a modified Rankin Scale (mRS) score of 0–2 at day 90. Results Ten UK centres enrolled 65 patients between April 2013 and April 2015. Median National Institutes of Health Stroke Scale score was 16 (IQR 13–21). Median stroke onset to IVT start was 120 min. In the intention-to-treat analysis, there was no significant difference in disability-free survival at day 90 with MT (absolute difference 11%, adjusted OR 2.12, 95% CI 0.65 to 6.94, p=0.20). Secondary analyses showed significantly greater likelihood of full neurological recovery (mRS 0–1) at day 90 (OR 7.6, 95% CI 1.6 to 37.2, p=0.010). In the per-protocol population (n=58), the primary and most secondary clinical outcomes significantly favoured MT (absolute difference in mRS 0–2 of 22% and adjusted OR 4.9, 95% CI 1.2 to 19.7, p=0.021). Conclusions The trial did not find a significant difference between treatment groups for the primary end point. However, the effect size was consistent with published data and across primary and secondary end points. Proceeding as fast as possible to MT after CTA confirmation of large artery occlusion on a background of intravenous alteplase is safe, improves excellent clinical outcomes and, in the per-protocol population, improves disability

  11. Effect of facemasks on empathy and relational continuity: a randomised controlled trial in primary care

    PubMed Central

    2013-01-01

    Background There is limited evidence to support the use of facemasks in preventing infection for primary care professionals. Negative effects on communication has been suggested when the physician wears a facemask. As communication skills and doctor patient relationship are essential to primary care consultations, the effects of doctor’s facemask wearing were explored. Method A randomised controlled study was conducted in primary care to explore the effects of doctors wearing facemasks on patients’ perception of doctors’ empathy, patient enablement and patient satisfaction. Primary care doctors were randomized to mask wearing and non mask wearing clinical consultations in public primary care clinics in Hong Kong. Patients’ views were gathered using the Consultation and Relational Empathy (CARE) Measure, Patient Enablement Instrument (PEI) and an overall satisfaction rating scale. The effects of face mask wearing were investigated using multilevel (hierarchical) modelling. Results 1,030 patients were randomised to doctor-mask wearing consultations (n = 514) and non mask wearing consultations (n = 516). A significant and negative effect was found in the patients’ perception of the doctors’ empathy (CARE score reduction -0.98, p-value = 0.04). In the more established doctor-patient relationship, the effect of doctors’ mask wearing was more pronounced (CARE score reduction -5.67, p-value = 0.03). Conclusion This study demonstrates that when doctors wearing a facemask during consultations, this has a significant negative impact on the patient’s perceived empathy and diminish the positive effects of relational continuity. Consideration should be taken in planning appropriate use of facemasks in infectious disease policy for primary care and other healthcare professionals at a national, local or practice level. Clinical trial registration This trial was registered on Chinese Clinical Trial Register (ChiCTR). Registration no.: ChiCTR-TTRCC-12002519

  12. Hypnosis Antenatal Training for Childbirth (HATCh): a randomised controlled trial [NCT00282204

    PubMed Central

    Cyna, Allan M; Andrew, Marion I; Robinson, Jeffrey S; Crowther, Caroline A; Baghurst, Peter; Turnbull, Deborah; Wicks, Graham; Whittle, Celia

    2006-01-01

    Background Although medical interventions play an important role in preserving lives and maternal comfort they have become increasingly routine in normal childbirth. This may increase the risk of associated complications and a less satisfactory birth experience. Antenatal hypnosis is associated with a reduced need for pharmacological interventions during childbirth. This trial seeks to determine the efficacy or otherwise of antenatal group hypnosis preparation for childbirth in late pregnancy. Methods/design A single centre, randomised controlled trial using a 3 arm parallel group design in the largest tertiary maternity unit in South Australia. Group 1 participants receive antenatal hypnosis training in preparation for childbirth administered by a qualified hypnotherapist with the use of an audio compact disc on hypnosis for re-enforcement; Group 2 consists of antenatal hypnosis training in preparation for childbirth using an audio compact disc on hypnosis administered by a nurse with no training in hypnotherapy; Group 3 participants continue with their usual preparation for childbirth with no additional intervention. Women > 34 and < 39 weeks gestation, planning a vaginal birth, not in active labour, with a singleton, viable fetus of vertex presentation, are eligible to participate. Allocation concealment is achieved using telephone randomisation. Participants assigned to hypnosis groups commence hypnosis training as near as possible to 37 weeks gestation. Treatment allocations are concealed from treating obstetricians, anaesthetists, midwives and those personnel collecting and analysing data. Our sample size of 135 women/group gives the study 80% power to detect a clinically relevant fall of 20% in the number of women requiring pharmacological analgesia – the primary endpoint. We estimate that approximately 5–10% of women will deliver prior to receiving their allocated intervention. We plan to recruit 150 women/group and perform sequential interim analyses

  13. COSMOS: COmparing Standard Maternity care with One-to-one midwifery Support: a randomised controlled trial

    PubMed Central

    McLachlan, Helen L; Forster, Della A; Davey, Mary-Ann; Lumley, Judith; Farrell, Tanya; Oats, Jeremy; Gold, Lisa; Waldenström, Ulla; Albers, Leah; Biro, Mary Anne

    2008-01-01

    Background In Australia and internationally, there is concern about the growing proportion of women giving birth by caesarean section. There is evidence of increased risk of placenta accreta and percreta in subsequent pregnancies as well as decreased fertility; and significant resource implications. Randomised controlled trials (RCTs) of continuity of midwifery care have reported reduced caesareans and other interventions in labour, as well as increased maternal satisfaction, with no statistically significant differences in perinatal morbidity or mortality. RCTs conducted in the UK and in Australia have largely measured the effect of teams of care providers (commonly 6–12 midwives) with very few testing caseload (one-to-one) midwifery care. This study aims to determine whether caseload (one-to-one) midwifery care for women at low risk of medical complications decreases the proportion of women delivering by caesarean section compared with women receiving 'standard' care. This paper presents the trial protocol in detail. Methods/design A two-arm RCT design will be used. Women who are identified at low medical risk will be recruited from the antenatal booking clinics of a tertiary women's hospital in Melbourne, Australia. Baseline data will be collected, then women randomised to caseload midwifery or standard low risk care. Women allocated to the caseload intervention will receive antenatal, intrapartum and postpartum care from a designated primary midwife with one or two antenatal visits conducted by a 'back-up' midwife. The midwives will collaborate with obstetricians and other health professionals as necessary. If the woman has an extended labour, or if the primary midwife is unavailable, care will be provided by the back-up midwife. For women allocated to standard care, options include midwifery-led care with varying levels of continuity, junior obstetric care and community based general medical practitioner care. Data will be collected at recruitment (self

  14. Parent-mediated communication-focused treatment in children with autism (PACT): a randomised controlled trial

    PubMed Central

    Green, Jonathan; Charman, Tony; McConachie, Helen; Aldred, Catherine; Slonims, Vicky; Howlin, Pat; Le Couteur, Ann; Leadbitter, Kathy; Hudry, Kristelle; Byford, Sarah; Barrett, Barbara; Temple, Kathryn; Macdonald, Wendy; Pickles, Andrew

    2010-01-01

    Summary Background Results of small trials suggest that early interventions for social communication are effective for the treatment of autism in children. We therefore investigated the efficacy of such an intervention in a larger trial. Methods Children with core autism (aged 2 years to 4 years and 11 months) were randomly assigned in a one-to-one ratio to a parent-mediated communication-focused (Preschool Autism Communication Trial [PACT]) intervention or treatment as usual at three specialist centres in the UK. Those assigned to PACT were also given treatment as usual. Randomisation was by use of minimisation of probability in the marginal distribution of treatment centre, age (≤42 months or >42 months), and autism severity (Autism Diagnostic Observation Schedule-Generic [ADOS-G] algorithm score 12–17 or 18–24). Primary outcome was severity of autism symptoms (a total score of social communication algorithm items from ADOS-G, higher score indicating greater severity) at 13 months. Complementary secondary outcomes were measures of parent-child interaction, child language, and adaptive functioning in school. Analysis was by intention to treat. This study is registered as an International Standard Randomised Controlled Trial, number ISRCTN58133827. Results 152 children were recruited. 77 were assigned to PACT (London [n=26], Manchester [n=26], and Newcastle [n=25]); and 75 to treatment as usual (London [n=26], Manchester [n=26], and Newcastle [n=23]). At the 13-month endpoint, the severity of symptoms was reduced by 3·9 points (SD 4·7) on the ADOS-G algorithm in the group assigned to PACT, and 2·9 (3·9) in the group assigned to treatment as usual, representing a between-group effect size of −0·24 (95% CI −0·59 to 0·11), after adjustment for centre, sex, socioeconomic status, age, and verbal and non-verbal abilities. Treatment effect was positive for parental synchronous response to child (1·22, 0·85 to 1·59), child initiations with parent (0·41

  15. Telerehabilitation to improve outcomes for people with stroke: study protocol for a randomised controlled trial

    PubMed Central

    2012-01-01

    Background In New Zealand, around 45,000 people live with stroke and many studies have reported that benefits gained during initial rehabilitation are not sustained. Evidence indicates that participation in physical interventions can prevent the functional decline that frequently occurs after discharge from acute care facilities. However, on-going stroke services provision following discharge from acute care is often related to non-medical factors such as availability of resources and geographical location. Currently most people receive no treatment beyond three months post stroke. The study aims to determine if the Augmented Community Telerehabilitation Intervention (ACTIV) results in better physical function for people with stroke than usual care, as measured by the Stroke Impact Scale, physical subcomponent. Methods/design This study will use a multi-site, two-arm, assessor blinded, parallel randomised controlled trial design. People will be eligible if they have had their first ever stroke, are over 20 and have some physical impairment in either arm or leg, or both. Following discharge from formal physiotherapy services (inpatient, outpatient or community), participants will be randomised into ACTIV or usual care. ACTIV uses readily available technology, telephone and mobile phones, combined with face-to-face visits from a physiotherapist over a six-month period, to help people with stroke resume activities they enjoyed before the stroke. The impact of stroke on physical function and quality of life will be assessed, measures of cost will be collected and a discrete choice survey will be used to measure preferences for rehabilitation options. These outcomes will be collected at baseline, six months and 12 months. In-depth interviews will be used to explore the experiences of people participating in the intervention arm of the study. Discussion The lack of on-going rehabilitation for people with stroke diminishes the chance of their best possible outcome and may

  16. A systematic review and meta-analysis of randomised controlled trials of treatments for clozapine-induced obesity and metabolic syndrome.

    PubMed

    Zimbron, Jorge; Khandaker, Golam M; Toschi, Chiara; Jones, Peter B; Fernandez-Egea, Emilio

    2016-09-01

    Metabolic complications are commonly found in people treated with clozapine. Reviews on the management of this problem have generally drawn conclusions by grouping different types of studies involving patients treated with various different antipsychotics. We carried out a systematic review and meta-analysis of pharmacological and non-pharmacological treatments for clozapine-induced obesity or metabolic syndrome. Two researchers independently searched PubMed and Embase for randomised controlled trials (RCTs) of treatments for clozapine-induced obesity or metabolic syndrome. All other types of studies were excluded. We only included RCTs where more than 50% of participants were taking clozapine. We identified 15 RCTs. Effective pharmacological treatments for clozapine-induced obesity and metabolic syndrome include metformin, aripiprazole, and Orlistat (in men only). Meta-analysis of three studies showed a robust effect of metformin in reducing body mass index and waist circumference but no effects on blood glucose, triglyceride levels, or HDL levels. In addition, there is limited evidence for combined calorie restriction and exercise as a non-pharmacological alternative for the treatment of clozapine-induced obesity, but only in an in-patient setting. Rosiglitazone, topiramate, sibutramine, phenylpropanolamine, modafinil, and atomoxetine have not shown to be beneficial, despite reports of efficacy in other populations treated with different antipsychotics. We conclude that randomised-controlled trial data support the use of metformin, aripiprazole, and Orlistat (in men only) for treating clozapine-induced obesity. Calorie restriction in combination with an exercise programme may be effective as a non-pharmacological alternative. Findings from trials in different populations should not be extrapolated to people being treated with clozapine.

  17. Design of a randomised acupuncture trial on functional neck/shoulder stiffness with two placebo controls

    PubMed Central

    2014-01-01

    Background Functional neck/shoulder stiffness is one of the most well-known indications for acupuncture treatment in Japan. There is little evidence for the effectiveness of acupuncture treatment for functional neck/shoulder stiffness. Research using two different placebos may allow an efficient method to tease apart the components of real acupuncture from various kinds of ‘non-specific’ effects such as ritual with touch or ritual alone. Herein, we describe a protocol of an ongoing, single-centre, randomised, placebo-controlled trial which aims to assess whether, in functional neck/shoulder stiffness, acupuncture treatment with skin piercing has a specific effect over two types of placebo: skin-touching plus ritual or ritual alone. Methods Six acupuncturists and 400 patients with functional neck/shoulder stiffness are randomly assigned to four treatment groups: genuine acupuncture penetrating the skin, skin-touch placebo or no-touch placebo needles in a double-blind manner (practitioner-patient blinding) or no-treatment control group. Each acupuncturist applies a needle to each of four acupoints (Bladder10, Small Intestine14, Gallbladder21 and Bladder42) in the neck/shoulder to 50 patients. Before, immediately after and 24 hours after the treatment, patients are asked about the intensity of their neck/shoulder stiffness. After the treatment, practitioners and patients are asked to guess whether the treatment is “penetrating”, “skin-touch” or “no-touch” or to record “cannot identify the treatment”. Discussion In addition to intention-to-treat analysis, we will conduct subgroup analysis based on practitioners’ or patients’ guesses to discuss the efficacy and effectiveness of treatments with skin piercing and various placebo controls. The results of practitioner and patient blinding will be discussed. We believe this study will further distinguish the role of different components of acupuncture. Trial registration Current Controlled Trial

  18. Successful GP intervention with frequent attenders in primary care: randomised controlled trial

    PubMed Central

    Bellón, Juan Ángel; Rodríguez-Bayón, Antonina; de Dios Luna, Juan; Torres-González, Francisco

    2008-01-01

    Background Frequent attenders to GP clinics can place an unnecessary burden on primary care. Interventions to reduce frequent attendance have had mixed results. Aim To assess the effectiveness of a GP intervention to reduce frequent-attender consultations. Design of study Randomised controlled trial with frequent attenders divided into an intervention group and two control groups (one control group was seen by GPs also providing care to patients undergoing the intervention). Setting A health centre in southern Spain. Method Six GPs and 209 randomly-selected frequent attenders participated. Three GPs were randomly allocated to perform the new intervention: of the 137 frequent attenders registered with these three GPs, 66 were randomly allocated to receive the intervention (IG) and 71 to a usual care control group (CG2). The other three GPs offered usual care to the other 72 frequent attenders (CG1). The main outcome measure was the total number of consultations 1 year post-intervention. Baseline measurements were recorded of sociodemographic characteristics, provider–user interface, chronic illnesses, and psychosocial variables. GPs allocated to the new intervention received 15 hours' training which incorporated biopsychosocial, organisational, and relational approaches. After 1 year of follow-up frequent attenders were contacted. An intention-to-treat analysis was used. Results A multilevel model was built with three factors: time, patient, and doctor. After adjusting for covariates, the mean number of visits at 1 year in IG was 13.10 (95% confidence interval [CI] = 11.39 to 14.94); in the CG1 group was 19.37 (95% CI = 17.31 to 21.55); and in the CG2 group this was 16.72 (95% CI =14.84 to 18.72). Conclusion The new intervention with GPs resulted in a significant and relevant reduction in frequent-attender consultations. Although further trials are needed, this intervention is recommended to GPs interested in reducing consultations by their frequent attenders

  19. Vojta therapy and neurodevelopmental treatment in children with infantile postural asymmetry: a randomised controlled trial

    PubMed Central

    Jung, Michael Wilhelm; Landenberger, Margarete; Jung, Tatjana; Lindenthal, Thorsten; Philippi, Heike

    2017-01-01

    [Purpose] Physical therapy is an acknowledged and frequently applied method for infantile postural asymmetry. However, there is not yet sufficient evidence for its effectiveness. [Subjects and Methods] In a randomised controlled trial, the effect of Vojta therapy versus Neurodevelopmental treatment is assessed in infants with postural asymmetry. 65 infants with postural asymmetry were recruited. 37 infants aged six to eight weeks (mean 7.38) were found to be eligible and randomly assigned to two groups, with 19 receiving Vojta and 18 Neurodevelopmental treatment. Using a standardised and blinded video-based assessment, we documented restriction in head rotation and convexity of the spine in prone and supine position before and after therapy. A reduction of at least four points (range of scale 20 points) in postural asymmetry was regarded as a clinically relevant change. [Results] On average a four-point reduction was achieved in both groups within eight weeks. A mean difference (pre-post) between the groups of −2.96 points in favour of Vojta therapy was observed. [Conclusion] While both Neurodevelopmental treatment and Vojta are effective in the treatment of infantile postural asymmetry and comparably well applied by the parents, therapeutic effectiveness is significant greater within the Vojta group. PMID:28265162

  20. Efficacy of metacognitive therapy for prolonged grief disorder: protocol for a randomised controlled trial

    PubMed Central

    Wenn, Jenine; O'Connor, Moira; Breen, Lauren J; Kane, Robert T; Rees, Clare S

    2015-01-01

    Introduction Studies of effective psychotherapy for individuals suffering from the effects of prolonged grief disorder (PGD) are scarce. This paper describes the protocol for an evaluation of a metacognitive therapy programme designed specifically for PGD, to reduce the psychological distress and loss of functioning resulting from bereavement. Methods and analysis The proposed trial comprises three phases. Phase 1 consists of a review of the literature and semistructured interviews with key members of the target population to inform the development of a metacognitive therapy programme for Prolonged Grief. Phase 2 involves a randomised controlled trial to implement and evaluate the programme. Male and female adults (N=34) will be randomly assigned to either a wait list or an intervention group. Measures of PGD, anxiety, depression, rumination, metacognitions and quality of life will be taken pretreatment and posttreatment and at the 3-month and 6-month follow-up. The generalised linear mixed model will be used to assess treatment efficacy. Phase 3 will test the social validity of the programme. Discussion This study is the first empirical investigation of the efficacy of a targeted metacognitive treatment programme for PGD. A focus on identifying and changing the metacognitive mechanisms underpinning the development and maintenance of prolonged grief is likely to be beneficial to theory and practice. Ethics Ethics approval was obtained from Curtin University Human Research Ethics Committee (Approval number HR 41/2013.) Trial registration number ACTRN12613001270707. PMID:26646828

  1. Feasibility of conducting a randomised controlled trial of a cookstove intervention in rural Malawi

    PubMed Central

    Kachidiku, J.; Banda, H.; Kapanga, M.; Doyle, J. V.; Banda, E.; Fox, C.; Gordon, S. B.; Mortimer, K.

    2014-01-01

    BACKGROUND: Exposure to household air pollution (HAP) causes 4 million deaths annually, and strategies to reduce HAP exposure are urgently required. OBJECTIVE: To evaluate the acceptability and feasibility of conducting a trial of a cookstove intervention in rural Malawi. DESIGN: Non-smoking women were randomised to continuing to use an open fire (control) or to using a wood-burning clay cookstove (intervention). Symptom burden, oxygen saturation and exhaled carbon monoxide (eCO) were assessed at baseline and 7-day follow-up. A subset of women underwent HAP exposure monitoring. RESULTS: Of 51 women recruited, 50 (98%) completed the main study. The methodology was acceptable to participants. Headache, back pain and cough were the most commonly reported symptoms at baseline and follow-up. Median eCO was within normal limits, but with a difference of 0.5 parts per million (ppm) in median change of eCO from baseline to follow-up seen between the two groups (P ∙ 0.035). The peak ambient CO concentration detected was 150 ppm. CONCLUSION: This study suggests that a large cookstove intervention trial in Malawi would be feasible with careful community sensitisation. Monitoring exposure to HAP is challenging, and further studies evaluating potential biomarkers of exposure, including eCO, should be undertaken. PMID:24429320

  2. A guide to performing a peer review of randomised controlled trials.

    PubMed

    Del Mar, Chris; Hoffmann, Tammy C

    2015-11-02

    Peer review of journal articles is an important step in the research process. Editors rely on the expertise of peer reviewers to properly assess submissions. Yet, peer review quality varies widely and few receive training or guidance in how to approach the task. This paper describes some of the main steps that peer reviewers in general and, in particular, those performing reviewes of randomised controlled trials (RCT), can use when carrying out a review. It can be helpful to begin with a brief read to acquaint yourself with the study, followed by a detailed read and a careful check for flaws. These can be divided into 'major' (problems that must be resolved before publication can be considered) and 'minor' (suggested improvements that are discretionary) flaws. Being aware of the appropriate reporting checklist for the study being reviewed (such as CONSORT and its extensions for RCTs) can also be valuable. Competing interests or prejudices might corrode the review, so ensuring transparency about them is important. Finally, ensuring that the paper's strengths are acknowledged along with a dissection of the weaknesses provides balance and perspective to both authors and editors. Helpful reviews are constructive and improve the quality of the paper. The proper conduct of a peer review is the responsibility of all who accept the role.

  3. Ketamine as the anaesthetic for electroconvulsive therapy: the KANECT randomised controlled trial.

    PubMed

    Fernie, Gordon; Currie, James; Perrin, Jennifer S; Stewart, Caroline A; Anderson, Virginica; Bennett, Daniel M; Hay, Steven; Reid, Ian C

    2017-03-02

    BackgroundKetamine has recently become an agent of interest as an acute treatment for severe depression and as the anaesthetic for electroconvulsive therapy (ECT). Subanaesthetic doses result in an acute reduction in depression severity while evidence is equivocal for this antidepressant effect with anaesthetic or adjuvant doses. Recent systematic reviews call for high-quality evidence from further randomised controlled trials (RCTs).AimsTo establish if ketamine as the anaesthetic for ECT results in fewer ECT treatments, improvements in depression severity ratings and less memory impairment than the standard anaesthetic.MethodDouble-blind, parallel-design, RCT of intravenous ketamine (up to 2 mg/kg) with an active comparator, intravenous propofol (up to 2.5 mg/kg), as the anaesthetic for ECT in patients receiving ECT for major depression on an informal basis. (Trial registration: European Clinical Trials Database (EudraCT): 2011-000396-14 and clinicalTrials.gov: NCT01306760)ResultsNo significant differences were found on any outcome measure during, at the end of or 1 month following the ECT course.ConclusionsKetamine as an anaesthetic does not enhance the efficacy of ECT.

  4. γ-Aminobutyric acid (GABA) administration improves action selection processes: a randomised controlled trial

    PubMed Central

    Steenbergen, Laura; Sellaro, Roberta; Stock, Ann-Kathrin; Beste, Christian; Colzato, Lorenza S.

    2015-01-01

    In order to accomplish a task goal, real-life environments require us to develop different action control strategies in order to rapidly react to fast-moving visual and auditory stimuli. When engaging in complex scenarios, it is essential to prioritise and cascade different actions. Recent studies have pointed to an important role of the gamma-aminobutyric acid (GABA)-ergic system in the neuromodulation of action cascading. In this study we assessed the specific causal role of the GABA-ergic system in modulating the efficiency of action cascading by administering 800 mg of synthetic GABA or 800 mg oral of microcrystalline cellulose (placebo). In a double-blind, randomised, between-group design, 30 healthy adults performed a stop-change paradigm. Results showed that the administration of GABA, compared to placebo, increased action selection when an interruption (stop) and a change towards an alternative response were required simultaneously, and when such a change had to occur after the completion of the stop process. These findings, involving the systemic administration of synthetic GABA, provide the first evidence for a possible causal role of the GABA-ergic system in modulating performance in action cascading. PMID:26227783

  5. Challenges associated with recruiting multigenerational, multicultural families into a randomised controlled trial: Balancing feasibility with validity.

    PubMed

    Hughes, Donna; Hutchinson, Amanda; Prichard, Ivanka; Chapman, Janine; Wilson, Carlene

    2015-07-01

    Recruitment of participants into research studies has become an increasingly difficult task with justifiable criticisms of representativeness of samples. The difficulties of recruitment are exacerbated when the study is longitudinal, requires multiple members from one family and incorporates people from non-dominant ethnic backgrounds. This paper describes a complex trial's recruitment process. Family groups were required for a longitudinal randomised controlled trial investigating links between health and dietary behaviours with an aim to improve primary prevention health messages and initiatives. To be representative of the multi-ethnic composition of the South Australian population, families from three of South Australia's largest ethnic backgrounds were invited to participate. Of these, only families with participating members spanning three generations were enrolled, so that links between health and lifestyle behaviours with possible generational ties could be investigated. Immense difficulties were faced during recruitment and significant modifications to the initial recruitment plan were necessary to enable the enrolment of 96 families. Challenges faced included lack of response to recruitment materials displaying complex eligibility criteria and different response outcomes from different communities. Solutions implemented included simplifying materials and tailoring recruitment activities to specific communities' needs. This trial's recruitment journey will be used as a case study to highlight the practicalities of recruiting for complex trials. Recommendations will be provided for future researchers seeking to recruit multigenerational, multi-ethnic families into the same study, along with issues to consider regarding the implications of the recruitment journey on the integrity of a complex trial and the potential threats to internal validity.

  6. Treatment of head louse infestation with 4% dimeticone lotion: randomised controlled equivalence trial

    PubMed Central

    Burgess, Ian F; Brown, Christine M; Lee, Peter N

    2005-01-01

    Objective To evaluate the efficacy and safety of 4% dimeticone lotion for treatment of head louse infestation. Design Randomised controlled equivalence trial. Setting Community, with home visits. Participants 214 young people aged 4 to 18 years and 39 adults with active head louse infestation. Interventions Two applications seven days apart of either 4.0% dimeticone lotion, applied for eight hours or overnight, or 0.5% phenothrin liquid, applied for 12 hours or overnight. Outcome measures Cure of infestation (no evidence of head lice after second treatment) or reinfestation after cure. Results Cure or reinfestation after cure occurred in 89 of 127 (70%) participants treated with dimeticone and 94 of 125 (75%) treated with phenothrin (difference -5%, 95% confidence interval -16% to 6%). Per protocol analysis showed that 84 of 121 (69%) participants were cured with dimeticone and 90 of 116 (78%) were cured with phenothrin. Irritant reactions occurred significantly less with dimeticone (3/127, 2%) than with phenothrin (11/125, 9%; difference -6%, -12% to -1%). Per protocol this was 3 of 121 (3%) participants treated with dimeticone and 10 of 116 (9%) treated with phenothrin (difference -6%, -12% to -0.3%). Conclusion Dimeticone lotion cures head louse infestation. Dimeticone seems less irritant than existing treatments and has a physical action on lice that should not be affected by resistance to neurotoxic insecticides. PMID:15951310

  7. Reporting quality of randomised controlled trials published in prosthodontic and implantology journals.

    PubMed

    Kloukos, D; Papageorgiou, S N; Doulis, I; Petridis, H; Pandis, N

    2015-12-01

    The purpose of this study was to examine the reporting quality of randomised controlled trials (RCTs) published in prosthodontic and implantology journals. Thirty issues of nine journals in prosthodontics and implant dentistry were searched for RCTs, covering the years 2005-2012: The Journal of Prosthetic Dentistry, Journal of Oral Rehabilitation, The International Journal of Prosthodontics, The International Journal of Periodontics & Restorative Dentistry, Clinical Oral Implants Research, Clinical Implant Dentistry & Related Research, The International Journal of Oral & Maxillofacial Implants, Implant Dentistry and Journal of Dentistry. The reporting quality was assessed using a modified Consolidated Standards of Reporting Trials (CONSORT) statement checklist. Data were analysed using descriptive statistics followed by univariable and multivariable examination of statistical associations (α = 0·05). A total of 147 RCTs were identified with a mean CONSORT score of 69·4 (s.d. = 9·7). Significant differences were found among journals with the Journal of Oral Rehabilitation achieving the highest score (80·6, s.d. = 5·5) followed by Clinical Oral Implants Research (73·7, s.d. = 8·3). Involvement of a statistician/methodologist was significantly associated with increased CONSORT scores. Overall, the reporting quality of RCTs in major prosthodontic and implantology journals requires improvement. This is of paramount importance considering that optimal reporting of RCTs is an important prerequisite for clinical decision-making.

  8. Vojta therapy and neurodevelopmental treatment in children with infantile postural asymmetry: a randomised controlled trial.

    PubMed

    Jung, Michael Wilhelm; Landenberger, Margarete; Jung, Tatjana; Lindenthal, Thorsten; Philippi, Heike

    2017-02-01

    [Purpose] Physical therapy is an acknowledged and frequently applied method for infantile postural asymmetry. However, there is not yet sufficient evidence for its effectiveness. [Subjects and Methods] In a randomised controlled trial, the effect of Vojta therapy versus Neurodevelopmental treatment is assessed in infants with postural asymmetry. 65 infants with postural asymmetry were recruited. 37 infants aged six to eight weeks (mean 7.38) were found to be eligible and randomly assigned to two groups, with 19 receiving Vojta and 18 Neurodevelopmental treatment. Using a standardised and blinded video-based assessment, we documented restriction in head rotation and convexity of the spine in prone and supine position before and after therapy. A reduction of at least four points (range of scale 20 points) in postural asymmetry was regarded as a clinically relevant change. [Results] On average a four-point reduction was achieved in both groups within eight weeks. A mean difference (pre-post) between the groups of -2.96 points in favour of Vojta therapy was observed. [Conclusion] While both Neurodevelopmental treatment and Vojta are effective in the treatment of infantile postural asymmetry and comparably well applied by the parents, therapeutic effectiveness is significant greater within the Vojta group.

  9. Antioxidant supplementation for the prevention of kwashiorkor in Malawian children: randomised, double blind, placebo controlled trial

    PubMed Central

    Ciliberto, Heather; Ciliberto, Michael; Briend, Andreé; Ashorn, Per; Bier, Dennis; Manary, Mark

    2005-01-01

    Objective To evaluate the efficacy of antioxidant supplementation in preventing kwashiorkor in a population of Malawian children at high risk of developing kwashiorkor. Design Prospective, double blind, placebo controlled trial randomised by household. Setting 8 villages in rural southern Malawi. Participants 2372 children in 2156 households aged 1-4 years were enrolled; 2332 completed the trial. Intervention Daily supplementation with an antioxidant powder containing riboflavin, vitamin E, selenium, and N-acetylcysteine in a dose that provided about three times the recommended dietary allowance of each nutrient or placebo for 20 weeks. Main outcome measures The primary outcome was the incidence of oedema. Secondary outcomes were the rates of change for weight and length and the number of days of infectious symptoms. Results 62 children developed kwashiorkor (defined by the presence of oedema); 39/1184 (3.3%) were in the antioxidant group and 23/1188 (1.9%) were in the placebo group (relative risk 1.70, 95% confidence interval 0.98 to 2.42). The two groups did not differ in rates of weight or height gain. Children who received antioxidant supplementation did not experience less fever, cough, or diarrhoea. Conclusions Antioxidant supplementation at the dose provided did not prevent the onset of kwashiorkor. This finding does not support the hypothesis that depletion of vitamin E, selenium, cysteine, or riboflavin has a role in the development of kwashiorkor. PMID:15851401

  10. A Randomised Controlled Trial of Treatment for Post-Stroke Homonymous Hemianopia: Screening and Recruitment

    PubMed Central

    Rowe, Fiona J.; Conroy, Elizabeth J.; Barton, P. Graham; Bedson, Emma; Cwiklinski, Emma; Dodridge, Caroline; Drummond, Avril; Garcia-Finana, Marta; Howard, Claire; Johnson, Stevie; MacIntosh, Claire; Noonan, Carmel P.; Pollock, Alex; Rockliffe, Janet; Sackley, Catherine M.; Shipman, Tracey

    2016-01-01

    ABSTRACT The authors report the screening process and recruitment figures for the VISION (Visual Impairment in Stroke; Intervention Or Not) trial. This is a prospective, randomised, single-blinded, three-arm controlled trial in 14 UK acute hospital stroke units. Stroke teams identified stroke survivors suspected as having homonymous hemianopia. Interventions included Fresnel prisms versus visual search training versus standard care (information only). Primary outcome was change in visual field assessment from baseline to 26 weeks. Secondary measures included change in quality-of-life questionnaires. Recruitment opened in May 2011. A total of 1171 patients were screened by the local principal investigators. Of 1171 patients, 178 (15.2%) were eligible for recruitment: 87 patients (7.4%) provided consent and were recruited; 91 patients (7.8%) did not provide consent, and 993 of 1171 patients (84.8%) failed to meet the eligibility criteria. Almost half were excluded due to complete/partial recovery of hemianopia (43.6%; n = 511). The most common ineligibility reason was recovery of hemianopia. When designing future trials in this area, changes in eligibility criteria/outcome selection to allow more patients to be recruited should be considered, e.g., less stringent levels of visual acuity/refractive error. Alternative outcomes measurable in the home environment, rather than requiring hospital attendance for follow-up, could facilitate increased recruitment. PMID:27928375

  11. Oral magnesium for relief in pregnancy-induced leg cramps: a randomised controlled trial.

    PubMed

    Supakatisant, Chayanis; Phupong, Vorapong

    2015-04-01

    Leg cramps are common in pregnant women. Currently, there is no standard treatment for pregnancy-induced leg cramps. The objective of this study was to evaluate the therapeutic efficacy of oral magnesium in pregnant women with leg cramps. This double-blinded, randomised, placebo-controlled trial included 86 healthy pregnant women, 14-34 weeks of gestation who had leg cramps at least twice per week. The study period was 4 weeks. Eighty women completed the study. Forty-one women were assigned to magnesium bisglycinate chelate (300 mg per day) and 39 women to placebo. Details of leg cramps were recorded before beginning the treatment and the fourth week of study. Outcome measure was the reduction of cramp frequency after treatment and cramp intensity measured by 100-mm visual analogue scale. Fifty per cent reduction of cramp frequency was significantly higher in the magnesium group than the placebo group (86.0% vs. 60.5%, P=0.007). The 50% reduction of cramp intensity was also significantly higher in the treatment group than in the placebo group (69.8% vs. 48.8%, P=0.048). There were no significant differences between the two groups in terms of side effects such as nausea and diarrhoea. These results demonstrated that oral magnesium supplement can improve the frequency and intensity of pregnancy-induced leg cramps. Therefore, oral magnesium may be a treatment option for women suffering from pregnancy-induced leg cramps.

  12. Effects of Green Tea on Streptococcus mutans Counts- A Randomised Control Trail

    PubMed Central

    R, Srinivas; B, Vikram Simha; Y, Sandhya Sree; T, Chandra Shekar; P, Siva Kumar

    2014-01-01

    Context: Mouth rinses have been in use from time immemorial as a supplement for routine oral hygiene. There are many number of mouth rinses currently available in the market in which many of them possess certain drawback, which has necessitated the search for alternate mouth rinses. Aim: The aim of the present study was to assess the effect of rinsing with green tea in comparison with chlorhexidine and plain water on Streptococcus mutans count. Setting and Design: A short term, single blinded, cross over randomised control clinical trial. Materials and Methods: Study includes a total of 30 subjects aged 20 to 25 years divided into three groups that is green tea group, chlorhexidine group, and plain water group. A baseline plaque samples were collected and under supervision of examiner all the subjects rinsed with 10 ml of respective solutions for one minute. Plaque samples were collected at five minutes after rinsing. All the 30 subjects were exposed to all the three rinses with a wash out period of seven days between the interventions. All the samples were sent to microbial analysis. Results: Wilcoxon matched pair test and Mann-Whitney U test showed that both chlorhexidine and green tea significantly reduced Streptococcus mutans colony counts compared to plain water. Conclusion: The results of present study indicate that green tea mouth rinse proved to be equally effective compared to chlorhexidine which is considered as gold standard. This may also be a valuable public health intervention as it is economical and has multiple health benefits. PMID:25584303

  13. A randomised, controlled, crossover trial of oral midazolam and nitrous oxide for paediatric dental sedation.

    PubMed

    Wilson, K E; Welbury, R R; Girdler, N M

    2002-09-01

    A randomised, controlled, crossover trial was designed to assess the safety and effectiveness of oral midazolam sedation for orthodontic extractions. Forty-six ASA physical status I children aged 10-16 years were recruited. Each child required two treatment sessions. Sedation with either oral midazolam 0.5 mg.kg-1 or nitrous oxide in oxygen was used at the first visit, the alternative being used at the second visit. Blood pressure, heart rate, arterial oxygen saturation, and sedation and behavioural scores were recorded every 5 min. Anxiety levels and postoperative satisfaction were also recorded. Blood pressure, heart rate and arterial oxygen saturation in both groups were similar and within acceptable clinical limits. The median [range] lowest arterial oxygen saturation levels for subjects in the midazolam and nitrous oxide groups were 95 [90-100]% and 98 [93-100]%, respectively. The median [range] time to the maximum level of sedation in the midazolam group was 20 [5-65] min compared with 5 [5-10] min in the nitrous oxide group (p < 0.001). The median [range] duration of treatment was similar in both groups (midazolam group: 10 [5-30] min, nitrous oxide group: 10 [5-25] min). Seventy-four per cent of subjects were prepared to have oral midazolam sedation again, 54% preferring it. Oral midazolam appears to be a safe and acceptable form of sedation for 10-16-year-old paediatric dental patients.

  14. Randomised controlled trial of a transprofessional healthcare role intervention in an acute medical setting.

    PubMed

    Kaltner, Melissa; Murtagh, Doug; Bennetts, Marguerite; Pighills, Alison; James, Julie; Scott, Annette

    2017-03-01

    As demand for health services increases, attention has turned to the development of alternate models of service delivery that maximise efficiency. These include skill sharing models, in which cross-professional skills are delivered by appropriately trained professionals. The usage of skill sharing models is increasing in some professions, but little evidence on efficacy currently exists. This article reports on an intervention of the use of a transprofessional role, which involved delivery of services from a range of health providers, including physiotherapy, occupational therapy, dietetics, speech pathology, podiatry, social work, and psychology, by a trained professional, developed and trialled in the acute medical setting in Toowoomba Hospital, Queensland, Australia. A single-blind randomised controlled trial examined the clinical efficacy of this skill shared service. Participants were allocated at random to either standard care (n = 29) or the new model of care (n = 29) groups and compared on a range of patient and service provision outcome measures. Descriptive outcomes indicated that patients receiving the new model of care underwent more comprehensive and prompt assessments in the health domains included than those in standard care, and demonstrated more positive health and functional outcomes at 1-, 3-, and 6-month follow-up. Given the paucity of research on skill sharing, this study provides preliminary evidence of the effectiveness of skill shared roles in acute settings.

  15. Robustness of DNA Repair through Collective Rate Control

    PubMed Central

    Manders, Erik; von Bornstaedt, Gesa; van Driel, Roel; Höfer, Thomas

    2014-01-01

    DNA repair and other chromatin-associated processes are carried out by enzymatic macromolecular complexes that assemble at specific sites on the chromatin fiber. How the rate of these molecular machineries is regulated by their constituent parts is poorly understood. Here we quantify nucleotide-excision DNA repair in mammalian cells and find that, despite the pathways' molecular complexity, repair effectively obeys slow first-order kinetics. Theoretical analysis and data-based modeling indicate that these kinetics are not due to a singular rate-limiting step. Rather, first-order kinetics emerge from the interplay of rapidly and reversibly assembling repair proteins, stochastically distributing DNA lesion repair over a broad time period. Based on this mechanism, the model predicts that the repair proteins collectively control the repair rate. Exploiting natural cell-to-cell variability, we corroborate this prediction for the lesion-recognition factor XPC and the downstream factor XPA. Our findings provide a rationale for the emergence of slow time scales in chromatin-associated processes from fast molecular steps and suggest that collective rate control might be a widespread mode of robust regulation in DNA repair and transcription. PMID:24499930

  16. Efficacy and safety of the Chaihuguizhiganjiang-suanzaoren granule on primary insomnia: study protocol for a randomised controlled trial

    PubMed Central

    Liu, Qing-Quan; Zhang, Jie; Guo, Rong-Juan; Xie, Ying-Zhen; Fu, Qing-Nan; He, Tian; Zhu, Xue-Qi; Du, Jie; Yang, Jing; Wang, Jia-Lin; Wei, Min-Min; Li, Qian-Qian; Shi, Guang-Xia; Liu, Cun-Zhi

    2016-01-01

    Introduction Insomnia is a highly prevalent, often debilitating and economically burdensome sleep disorder with limited effective therapies. Few data are available to understand which of the therapeutic alternatives is the most effective for patients with insomnia, especially for Traditional Chinese Medicine (TCM). Chinese herbal medicine, as a typical TCM, is one of the most popular complementary and alternative therapies for insomnia. We aim to evaluate the efficacy and safety of the Chaihuguizhiganjiang-suanzaoren granule (CSG), a Chinese herbal medicine treatment, in patients with primary insomnia. Methods and analysis This is a multicentre, placebo-controlled, double-blinded, randomised controlled clinical trial. A total of 258 participants are randomly allocated to two groups: the intervention group or the placebo group. The intervention group receives CSG and the placebo group receives a placebo granule. The patients receive either CSG or placebo two times daily for 8 weeks. The primary outcome is the Pittsburgh sleep quality index (PSQI). Secondary outcomes include the Insomnia Severity Index (ISI), Total Sleep Time (TST) and the Short-Form Health Survey (SF-36). The assessment is performed at baseline (before randomisation), 4, 8 and 12 weeks after randomisation. Ethics and dissemination The protocol has been approved by the Research Ethical Committee of Beijing Hospital of Traditional Chinese Medicine Affiliated to Capital Medical University (reference: 2014BL-003-01). The trial will be helpful in identifying the efficacy and safety of CSG in patients with primary insomnia. Trial registration number ISRCTN22001145; Pre-results. PMID:26839010

  17. Protocol for Acupuncture Treatment of Lateral Elbow Pain: A Multisite Randomised Controlled Trial in China, Hong Kong, Australia, and Italy

    PubMed Central

    Berle, Christine; Li, Wei Hong; Li, Tie; Wang, Fu Chun; Bangrazi, Sergio; Li, Lei; Liguori, Stefano; Liu, Yan Song

    2016-01-01

    Background. Lateral elbow pain is one of the most common musculoskeletal pains associated with the upper limb and has an estimated population incidence of 1–3%. Methods/Design. This study protocol is for a multisite randomised controlled study and is designed to evaluate the clinical efficacy of acupuncture in the treatment of chronic (over three months' duration) lateral elbow pain. Four study sites, in the People's Republic of China, Hong Kong, Italy, and Australia, will recruit 24 participants each. A total of 96 participants will be randomised to either an acupuncture group or a sham laser control group. The primary outcome measure will be the Disabilities of Arm, Shoulder, and Hand questionnaire with secondary outcome measures of Pain-Free Grip Strength Test, Muscle Tension Test, and a pain visual analogue scale. Discussion. Key features for conducting a multisite international acupuncture randomised clinical trial have been detailed in this protocol. Trial Registration. This trial is registered at Australian and New Zealand Clinical Trial Registry ACTRN12613001138774 on 11 October, 2013. PMID:27994627

  18. Nutritional route in oesophageal resection trial II (NUTRIENT II): study protocol for a multicentre open-label randomised controlled trial

    PubMed Central

    Berkelmans, Gijs H K; Wilts, Bas J W; Kouwenhoven, Ewout A; Kumagai, Koshi; Nilsson, Magnus; Weijs, Teus J; Nieuwenhuijzen, Grard A P; van Det, Marc J; Luyer, Misha D P

    2016-01-01

    Introduction Early start of an oral diet is safe and beneficial in most types of gastrointestinal surgery and is a crucial part of fast track or enhanced recovery protocols. However, the feasibility and safety of oral intake directly following oesophagectomy remain unclear. The aim of this study is to investigate the effects of early versus delayed start of oral intake on postoperative recovery following oesophagectomy. Methods and analysis This is an open-label multicentre randomised controlled trial. Patients undergoing elective minimally invasive or hybrid oesophagectomy for cancer are eligible. Further inclusion criteria are intrathoracic anastomosis, written informed consent and age 18 years or older. Inability for oral intake, inability to place a feeding jejunostomy, inability to provide written consent, swallowing disorder, achalasia, Karnofsky Performance Status <80 and malnutrition are exclusion criteria. Patients will be randomised using online randomisation software. The intervention group (direct oral feeding) will receive a liquid oral diet for 2 weeks with gradually expanding daily maximums. The control group (delayed oral feeding) will receive enteral feeding via a jejunostomy during 5 days and then start the same liquid oral diet. The primary outcome measure is functional recovery. Secondary outcome measures are 30-day surgical complications; nutritional status; need for artificial nutrition; need for additional interventions; health-related quality of life. We aim to recruit 148 patients. Statistical analysis will be performed according to an intention to treat principle. Results are presented as risk ratios with corresponding 95% CIs. A two-tailed p<0.05 is considered statistically significant. Ethics and dissemination Our study protocol has received ethical approval from the Medical research Ethics Committees United (MEC-U). This study is conducted according to the principles of Good Clinical Practice. Verbal and written informed consent is

  19. Effect of Oral Lactoferrin on Cataract Surgery Induced Dry Eye: A Randomised Controlled Trial

    PubMed Central

    Singh, Sneha

    2015-01-01

    Context Cataract surgery is one of the most frequently performed intra-ocular surgeries, of these manual Small Incision Cataract Surgery (SICS) is a time tested technique of cataract removal. Any corneal incisional surgery, including cataract surgery, can induce dry eye postoperatively. Various factors have been implicated, of which oneis the inflammation induced by the surgery. Lactoferrin, a glycoprotein present in tears is said to have anti-inflammatory effects, and promotes cell growth. It has been used orally in patients of immune mediated dry eye to alleviate symptoms. Aim This study was aimed to evaluate the dry eyes induced by manual Small Incision Cataract Surgery, and the effect if any, of oral lactoferrin on the dry eyes. Settings and Trial Design A single centre, prospective randomised controlled trial with a concurrent parallel design. The study was carried out on patients presenting in the OPD of Rohilkhand Medical College hospital for cataract surgery. Materials and Methods Sixty four patients of cataract surgery were included in the study. Patients with pre-existing dry eyes, ocular disease or systemic disease predisposing to dry eyes were excluded from the study. The selected patients were assigned into two groups by simple randomisation-Control Group A-32 patients that did not receive oral lactoferrin postoperatively. Group B-32 patients that received oral lactoferrin 350 gm postoperatively from day 1 after SICS. All patients were operated for cataract and their pre and postoperative (on days 7, 14, 30 and 60) dry eye status was assessed using the mean tear film break-up time (tBUT) and Schirmer test 1 (ST 1) as the evaluating parameters. Subjective evaluation of dry eye was done using Ocular Surface Disease Index (OSDI) scoring. Data was analysed for 58 patients, as 6 did not complete the follow up. Statistical Analysis Unpaired t-test was used to calculate the p-values. Result There was a statistically significant difference between the t

  20. Designing a robust minimum variance controller using discrete slide mode controller approach.

    PubMed

    Alipouri, Yousef; Poshtan, Javad

    2013-03-01

    Designing minimum variance controllers (MVC) for nonlinear systems is confronted with many difficulties. The methods able to identify MIMO nonlinear systems are scarce. Harsh control signals produced by MVC are among other disadvantages of this controller. Besides, MVC is not a robust controller. In this article, the Vector ARX (VARX) model is used for simultaneously modeling the system and disturbance in order to tackle these disadvantages. For ensuring the robustness of the control loop, the discrete slide mode controller design approach is used in designing MVC and generalized MVC (GMVC). The proposed method for controller design is tested on a nonlinear experimental Four-Tank benchmark process and is compared with nonlinear MVCs designed by neural networks. In spite of the simplicity of designing GMVCs for the VARX models with uncertainty, the results show that the proposed method is accurate and implementable.

  1. One year effectiveness of an individualised smoking cessation intervention at the workplace: a randomised controlled trial

    PubMed Central

    Rodriguez-Artalej..., F; Lafuente, U; Guallar-Castillon, P; Garteizaurrekoa, D.; Sainz, M; Diez, A; Foj, A; Banegas, J

    2003-01-01

    Aims: To assess the effectiveness of a smoking cessation intervention at the workplace. The intervention was adapted to smokers‘ tobacco dependence, and included minimal structured counselling at the first visit (5–8 minutes), nicotine patches for three months, and three sessions of counselling for reinforcement of abstinence (2–3 minutes) over a three month period. Methods: Open randomised trial with two groups: the intervention group, and the control group which was subjected to standard clinical practice, consisting of short (30 seconds to one minute) sporadic sessions of unstructured medical antismoking advice. The trial was carried out among 217 smokers of both sexes, aged 20–63 years, motivated to quit smoking and without contraindications for nicotine patches, who were employees at a public transport company and at two worksites of an electric company. The main outcome measure was self reported tobacco abstinence confirmed by carbon monoxide in expired air ≤10 ppm. Analysis was performed according to intention-to-treat. Results: The rate of continuous abstinence at 12 months was 20.2% for the intervention versus 8.7% for the control group (OR: 2.58; 95% CI: 1.13 to 5.90; p = 0.025). In subgroup analyses, effectiveness of the intervention did not vary substantially with age, tobacco dependence, number of cigarettes smoked per day, number of years of tobacco consumption, degree of desire to quit smoking, time spent with smokers, subjective health, and presence of tobacco related symptoms. Weight gain at 12 months was similar for both groups (1.69 kg in the intervention v 2.01 kg in the control group; p = 0.21). Conclusions: A simple and easily generalisable intervention at the workplace is effective to achieve long term smoking cessation. In a setting similar to ours, nine subjects would have to be treated for three months for one to achieve continuous abstinence for 12 months. PMID:12709522

  2. Insecticide impregnated curtains to control domestic transmission of cutaneous leishmaniasis in Venezuela: cluster randomised trial

    PubMed Central

    Kroeger, Axel; Avila, Elci Villegas; Morison, Linda

    2002-01-01

    Objective To measure the impact on transmission of leishmaniasis of curtains impregnated with insecticide. Design Cluster randomised controlled trial: household interview survey, observational study of people's behaviour, entomological study with light trap captures of sandflies inside houses. Setting 14 urban sectors in Trujillo, Venezuela. Participants 2913 inhabitants of 569 houses. Intervention Sectors were paired according to their 12 month cumulative incidence of cutaneous leishmaniasis, one sector in each pair was randomly allocated to receive polyester curtains impregnated with lambdacyhalothrin (intervention group) while the other sector received curtains without insecticide or no curtains (control groups). After 12 months a follow up household survey was conducted. Main outcome measures Reduction in abundance of sandflies indoors and 12 month incidence of clinical cases of cutaneous leishmaniasis. Results Transmission of cutaneous leishmaniasis occurred mainly in the domestic setting, with the incidence over 12 months of 4%. The mean number of sandflies per trap per night was 16. After follow up the 12 month incidence of cutaneous leishmaniasis was 0% in the intervention group and 8% in the six pairs in the control group that received unimpregnated curtains (mean difference 8, 95% confidence interval 4.22 to 11.78; P=0.001). There were significantly fewer sandflies in the intervention group (2 v 15, mean difference 13 sandflies per trap; 9 to 17; P<0.001). Conclusion Curtains impregnated with insecticide provide a high degree of protection against indoor transmission of cutaneous leishmaniasis. What is already known on this topicThe transmission of cutaneous leishmaniasis is increasingly in urban and domestic settingsHouse spraying, space spraying, and insecticide treated material reduce the number of vectorsWhat this paper addsPyrethroid impregnated curtains can considerably reduce the incidence rate of cutaneous leishmaniasis in areas where indoor

  3. Effectiveness of telephone counselling by a pharmacist in reducing mortality in patients receiving polypharmacy: randomised controlled trial

    PubMed Central

    Wu, Jennifer Y F; Leung, Wilson Y S; Chang, Sophie; Lee, Benjamin; Zee, Benny; Tong, Peter C Y; Chan, Juliana C N

    2006-01-01

    Objective To investigate the effects of compliance and periodic telephone counselling by a pharmacist on mortality in patients receiving polypharmacy. Design Two year randomised controlled trial. Setting Hospital medical clinic. Participants 502 of 1011 patients receiving five or more drugs for chronic disease found to be non-compliant at the screening visit were invited for randomisation to either the telephone counselling group (n = 219) or control group (n = 223) at enrolment 12-16 weeks later. Main outcome measures Primary outcome was all cause mortality in randomised patients. Associations between compliance and mortality in the entire cohort of 1011 patients were also examined. Patients were defined as compliant with a drug if they took 80-120% of the prescribed daily dose. To calculate a compliance score for the whole treatment regimen, the number of drugs that the patient was fully compliant with was divided by the total number of prescribed drugs and expressed as a percentage. Only patients who complied with all recommended drugs were considered compliant (100% score). Results 60 of the 502 eligible patients defaulted and only 442 patients were randomised. After two years, 31 (52%) of the defaulters had died, 38 (17%) of the control group had died, and 25 (11%) of the intervention group had died. After adjustment for confounders, telephone counselling was associated with a 41% reduction in the risk of death (relative risk 0.59, 95% confidence interval 0.35 to 0.97; P = 0.039). The number needed to treat to prevent one death at two years was 16. Other predictors included old age, living alone, rate of admission to hospital, compliance score, number of drugs for chronic disease, and non-treatment with lipid lowering drugs at screening visit. In the cohort of 1011 patients, the adjusted relative risk for death was 1.61 (1.05 to 2.48; P = 0.029) and 2.87 (1.80 to 2.57; P < 0.001) in patients with compliance scores of 34-66% and 0-33%, respectively, compared

  4. Robust reliable sampled-data control for switched systems with application to flight control

    NASA Astrophysics Data System (ADS)

    Sakthivel, R.; Joby, Maya; Shi, P.; Mathiyalagan, K.

    2016-11-01

    This paper addresses the robust reliable stabilisation problem for a class of uncertain switched systems with random delays and norm bounded uncertainties. The main aim of this paper is to obtain the reliable robust sampled-data control design which involves random time delay with an appropriate gain control matrix for achieving the robust exponential stabilisation for uncertain switched system against actuator failures. In particular, the involved delays are assumed to be randomly time-varying which obeys certain mutually uncorrelated Bernoulli distributed white noise sequences. By constructing an appropriate Lyapunov-Krasovskii functional (LKF) and employing an average-dwell time approach, a new set of criteria is derived for ensuring the robust exponential stability of the closed-loop switched system. More precisely, the Schur complement and Jensen's integral inequality are used in derivation of stabilisation criteria. By considering the relationship among the random time-varying delay and its lower and upper bounds, a new set of sufficient condition is established for the existence of reliable robust sampled-data control in terms of solution to linear matrix inequalities (LMIs). Finally, an illustrative example based on the F-18 aircraft model is provided to show the effectiveness of the proposed design procedures.

  5. A cost effectiveness analysis within a randomised controlled trial of post-acute care of older people in a community hospital

    PubMed Central

    O'Reilly, Jacqueline; Lowson, Karin; Young, John; Forster, Anne; Green, John; Small, Neil

    2006-01-01

    Objective To assess the cost effectiveness of post-acute care for older people in a locality based community hospital compared with a department for care of elderly people in a district general hospital, which admits patients aged over 76 years with acute medical conditions. Design Cost effectiveness analysis within a randomised controlled trial. Setting Community hospital and district general hospital in Yorkshire, England. Participants 220 patients needing rehabilitation after an acute illness for which they required admission to hospital. Interventions Multidisciplinary care in the district general hospital or prompt transfer to the community hospital. Main outcome measures EuroQol EQ-5D scores transformed into quality adjusted life years (QALYs), and health and social service costs over six months from randomisation. Results The mean QALY score for the community hospital group was marginally non-significantly higher than that for the district general hospital group (0.38 v 0.35) at six months after recruitment. The mean (standard deviation) costs per patient of the health and social services resources used were similar for both groups: community hospital group £7233 (euros 10 567; $13 341) (£5031), district general hospital group £7351 (£6229), and these findings were robust to several sensitivity analyses. The incremental cost effectiveness ratio for community hospital care dominated. A cost effectiveness acceptability curve, based on bootstrapped simulations, suggests that at a willingness to pay threshold of £10 000 per QALY, 51% of community hospital cases will be cost effective, which rises to 53% of cases when the threshold is £30 000 per QALY. Conclusion Post-acute care for older people in a locality based community hospital is of similar cost effectiveness to that of an elderly care department in a district general hospital. PMID:16861254

  6. Robust control of multi-jointed arm with a decentralized autonomous control mechanism

    NASA Technical Reports Server (NTRS)

    Kimura, Shinichi; Miyazaki, Ken; Suzuki, Yoshiaki

    1994-01-01

    A decentralized autonomous control mechanism applied to the control of three dimensional manipulators and its robustness to partial damage was assessed by computer simulation. Decentralized control structures are believed to be quite robust to time delay between the operator and the target system. A 10-jointed manipulator based on our control mechanism was able to continue its positioning task in three-dimensional space without revision of the control program, even after some of its joints were damaged. These results suggest that this control mechanism can be effectively applied to space telerobots, which are associated with serious time delay between the operator and the target system, and which cannot be easily repaired after being partially damaged.

  7. Managed Activity Graded Exercise iN Teenagers and pre-Adolescents (MAGENTA) feasibility randomised controlled trial: study protocol

    PubMed Central

    Brigden, Amberly; Beasant, Lucy; Hollingworth, William; Metcalfe, Chris; Gaunt, Daisy; Mills, Nicola; Jago, Russell; Crawley, Esther

    2016-01-01

    Introduction Paediatric chronic fatigue syndrome or myalgic encephalomyelitis (CFS/ME) is a relatively common and disabling condition, yet there is a limited evidence base for treatment. There is good evidence that graded exercise therapy is moderately effective in adults with CFS/ME, but there is little evidence for the effectiveness, cost-effectiveness, acceptability or best method of delivery for paediatric CFS/ME. This study aims to investigate the acceptability and feasibility of carrying out a multicentre randomised controlled trial investigating the effectiveness of graded exercise therapy compared with activity management for children/teenagers who are mildly or moderately affected with CFS/ME. Methods and analysis 100 paediatric patients (8–17 years) with CFS/ME will be recruited from 3 specialist UK National Health Service (NHS) CFS/ME services (Bath, Cambridge and Newcastle). Patients will be randomised (1:1) to receive either graded exercise therapy or activity management. Feasibility analysis will include the number of young people eligible, approached and consented to the trial; attrition rate and treatment adherence; questionnaire and accelerometer completion rates. Integrated qualitative methods will ascertain perceptions of feasibility and acceptability of recruitment, randomisation and the interventions. All adverse events will be monitored to assess the safety of the trial. Ethics and dissemination The trial has received ethical approval from the National Research Ethics Service (South West—Frenchay 15/SW/0124). Trial registration number ISRCTN23962803; Pre-results. PMID:27377634

  8. Protocol to evaluate the impact of yoga supplementation on cognitive function in schizophrenia: a randomised controlled trial

    PubMed Central

    Bhatia, Triptish; Mazumdar, Sati; Mishra, Nagendra Narayan; Gur, Raquel E.; Gur, Ruben C.; Nimgaonkar, Vishwajit Laxmikant; Deshpande, Smita Neelkanth

    2015-01-01

    Background Schizophrenia (SZ) is a chronic illness that is treated symptomatically. Cognitive dysfunction is a core feature of SZ that is relatively intractable to pharmacotherapy. Yoga can improve cognitive function among healthy individuals. A recent open trial indicated significant benefits of yoga training (YT) in conjunction with conventional pharmacotherapy among patients with SZ. Aims To describe the protocol for an ongoing randomised controlled trial designed to test whether the reported beneficial effects of YT on cognitive function among SZ patients can be replicated. Secondarily, the effects of YT on daily functioning living skills are evaluated. Methods Consenting patients with SZ receive routine clinical treatment and are randomised to adjunctive YT, adjunctive physical exercise (PE) or treatment as usual (proposed N = 234 total, N = 78 in each group). The trial involves YT or PE 5 days a week and lasts 3 weeks. Participants are evaluated thrice over 6 months. Cognitive functions measured by Trail Making Test, University of Pennsylvania Neurocognitive Computerised Battery were primary outcome measures while clinical severity and daily functioning measured by Independent Living Skills Survey were secondary outcome measures. Results A total of 309 participants have been randomised as of 31 August 2013, which exceeded beyond 294 proposed after attrition. Once participants begin YT or PE they generally complete the protocol. No injuries have been reported. Conclusions Short term YT is feasible and acceptable to Indian SZ patients. If beneficial effects of YT are detected, it will provide a novel adjunctive cognitive remediation strategy for SZ patients. PMID:25241756

  9. A multi-centre randomised controlled trial of Transfusion Indication Threshold Reduction on transfusion rates, morbidity and healthcare resource use following cardiac surgery: Study protocol

    PubMed Central

    Brierley, Rachel C.M.; Pike, Katie; Miles, Alice; Wordsworth, Sarah; Stokes, Elizabeth A.; Mumford, Andrew D.; Cohen, Alan; Angelini, Gianni D.; Murphy, Gavin J.; Rogers, Chris A.; Reeves, Barnaby C.

    2014-01-01

    Thresholds for red blood cell transfusion following cardiac surgery vary by hospital and surgeon. The TITRe2 multi-centre randomised controlled trial aims to randomise 2000 patients from 17 United Kingdom centres, and tests the hypothesis that a restrictive transfusion threshold will reduce postoperative morbidity and health service costs compared to a liberal threshold. Patients consent to take part in the study pre-operatively but are only randomised if their haemoglobin falls below 9 g/dL during their post-operative hospital stay. The primary outcome is a binary composite outcome of any serious infectious or ischaemic event in the first three months after randomisation. Many challenges have been encountered in the set-up and running of the study. PMID:24675014

  10. Group hypnosis vs. relaxation for smoking cessation in adults: a cluster-randomised controlled trial

    PubMed Central

    2013-01-01

    Background Despite the popularity of hypnotherapy for smoking cessation, the efficacy of this method is unclear. We aimed to investigate the efficacy of a single-session of group hypnotherapy for smoking cessation compared to relaxation in Swiss adult smokers. Methods This was a cluster-randomised, parallel-group, controlled trial. A single session of hypnosis or relaxation for smoking cessation was delivered to groups of smokers (median size = 11). Participants were 223 smokers consuming ≥ 5 cigarettes per day, willing to quit and not using cessation aids (47.1% females, M = 37.5 years [SD = 11.8], 86.1% Swiss). Nicotine withdrawal, smoking abstinence self-efficacy, and adverse reactions were assessed at a 2-week follow-up. The main outcome, self-reported 30-day point prevalence of smoking abstinence, was assessed at a 6-month follow up. Abstinence was validated through salivary analysis. Secondary outcomes included number of cigarettes smoked per day, smoking abstinence self-efficacy, and nicotine withdrawal. Results At the 6-month follow up, 14.7% in the hypnosis group and 17.8% in the relaxation group were abstinent. The intervention had no effect on smoking status (p = .73) or on the number of cigarettes smoked per day (p = .56). Smoking abstinence self-efficacy did not differ between the interventions (p = .14) at the 2-week follow-up, but non-smokers in the hypnosis group experienced reduced withdrawal (p = .02). Both interventions produced few adverse reactions (p = .81). Conclusions A single session of group hypnotherapy does not appear to be more effective for smoking cessation than a group relaxation session. Trial registration Current Controlled Trials ISRCTN72839675. PMID:24365274

  11. Falls and mobility in Parkinson's disease: protocol for a randomised controlled clinical trial

    PubMed Central

    2011-01-01

    Background Although physical therapy and falls prevention education are argued to reduce falls and disability in people with idiopathic Parkinson's disease, this has not yet been confirmed with a large scale randomised controlled clinical trial. The study will investigate the effects on falls, mobility and quality of life of (i) movement strategy training combined with falls prevention education, (ii) progressive resistance strength training combined with falls prevention education, (iii) a generic life-skills social program (control group). Methods/Design People with idiopathic Parkinson's disease who live at home will be recruited and randomly allocated to one of three groups. Each person shall receive therapy in an out-patient setting in groups of 3-4. Each group shall be scheduled to meet once per week for 2 hours for 8 consecutive weeks. All participants will also have a structured 2 hour home practice program for each week during the 8 week intervention phase. Assessments will occur before therapy, after the 8 week therapy program, and at 3 and 12 months after the intervention. A falls calendar will be kept by each participant for 12 months after outpatient therapy. Consistent with the recommendations of the Prevention of Falls Network Europe group, three falls variables will be used as the primary outcome measures: the number of fallers, the number of multiple fallers and the falls rate. In addition to quantifying falls, we shall measure mobility, activity limitations and quality of life as secondary outcomes. Discussion This study has the potential to determine whether outpatient movement strategy training combined with falls prevention education or progressive resistance strength training combined with falls prevention education are effective for reducing falls and improving mobility and life quality in people with Parkinson's disease who live at home. Trial registration Australia and New Zealand Clinical Trials Register (ANZCTR): ACTRN12606000344594 PMID

  12. Children Learning About Secondhand Smoke (CLASS II): protocol of a pilot cluster randomised controlled trial

    PubMed Central

    Siddiqi, Kamran; Huque, Rumana; Jackson, Cath; Parrott, Steve; Dogar, Omara; Shah, Sarwat; Thomson, Heather; Sheikh, Aziz

    2015-01-01

    Introduction Exposure to secondhand smoke (SHS) increases children’s risk of acquiring chest and ear infections, tuberculosis, meningitis and asthma. Smoking bans in public places (where implemented) have significantly reduced adults’ exposure to SHS. However, for children, homes remain the most likely place for them to be exposed to SHS. Additional measures are therefore required to protect children from SHS. In a feasibility study in Dhaka, Bangladesh, we have shown that a school-based smoke-free intervention (SFI) was successful in encouraging children to negotiate and implement smoking restrictions in homes. We will now conduct a pilot trial to inform plans to undertake a cluster randomised controlled trial (RCT) investigating the effectiveness and cost-effectiveness of SFI in reducing children’s exposure to SHS. Methods and analysis We plan to recruit 12 primary schools in Dhaka, Bangladesh. From these schools, we will recruit approximately 360 schoolchildren in year 5 (10–12 years old), that is, 30 per school. SFI consists of six interactive educational activities aimed at increasing pupils’ knowledge about SHS and related harms, motivating them to act, providing skills to negotiate with adults to persuade them not to smoke inside homes and helping families to ‘sign-up’ to a voluntary contract to make their homes smoke-free. Children in the control arm will receive the usual education. We will estimate: recruitment and attrition rates, acceptability, fidelity to SFI, effect size, intracluster correlation coefficient, cost of intervention and adverse events. Our primary outcome will consist of SHS exposure in children measured by salivary cotinine. Secondary outcomes will include respiratory symptoms, lung function tests, healthcare contacts, school attendance, smoking uptake, quality of life and academic performance. Ethics and dissemination The trial has received ethics approval from the Research Governance Committee at the University of York

  13. Robustness and Actuator Bandwidth of MRP-Based Sliding Mode Control for Spacecraft Attitude Control Problems

    NASA Astrophysics Data System (ADS)

    Keum, Jung-Hoon; Ra, Sung-Woong

    2009-12-01

    Nonlinear sliding surface design in variable structure systems for spacecraft attitude control problems is studied. A robustness analysis is performed for regular form of system, and calculation of actuator bandwidth is presented by reviewing sliding surface dynamics. To achieve non-singular attitude description and minimal parameterization, spacecraft attitude control problems are considered based on modified Rodrigues parameters (MRP). It is shown that the derived controller ensures the sliding motion in pre-determined region irrespective of unmodeled effects and disturbances.

  14. Control design for robust stability in linear regulators: Application to aerospace flight control

    NASA Technical Reports Server (NTRS)

    Yedavalli, R. K.

    1986-01-01

    Time domain stability robustness analysis and design for linear multivariable uncertain systems with bounded uncertainties is the central theme of the research. After reviewing the recently developed upper bounds on the linear elemental (structured), time varying perturbation of an asymptotically stable linear time invariant regulator, it is shown that it is possible to further improve these bounds by employing state transformations. Then introducing a quantitative measure called the stability robustness index, a state feedback conrol design algorithm is presented for a general linear regulator problem and then specialized to the case of modal systems as well as matched systems. The extension of the algorithm to stochastic systems with Kalman filter as the state estimator is presented. Finally an algorithm for robust dynamic compensator design is presented using Parameter Optimization (PO) procedure. Applications in a aircraft control and flexible structure control are presented along with a comparison with other existing methods.

  15. Alexander Technique Lessons, Acupuncture Sessions or usual care for patients with chronic neck pain (ATLAS): study protocol for a randomised controlled trial

    PubMed Central

    2013-01-01

    self-care and lifestyle. Qualitative material will be used to address issues of safety, acceptability and factors that impact on longer term outcomes. Discussion This study will provide robust evidence on whether there are significant clinical benefits to patients, economic benefits demonstrating value for money, and sufficient levels of acceptability and safety. Trial registration Current Controlled Trials ISRCTN15186354 PMID:23841901

  16. TREC-SAVE: a randomised trial comparing mechanical restraints with use of seclusion for aggressive or violent seriously mentally ill people: study protocol for a randomised controlled trial

    PubMed Central

    2011-01-01

    Background Thousands of people whose aggression is thought due to serious mental illness are secluded or restrained every day. Without fair testing these techniques will continue to be used outside of a rigorous evidence base. With such coercive treatment this leaves all concerned vulnerable to abuse and criticism. This paper presents the protocol for a randomised trial comparing seclusion with restraints for people with serious mental illnesses. Methods/Design Setting-General psychiatric wards of a large psychiatric hospital in Rio de Janeiro, Brazil. Participants-Anyone aggressive or violent suspected or known to have serious mental illness for whom restriction is felt to be indicated by nursing and medical staff, but also for whom they are unsure whether seclusion or restraint would be indicated. Interventions-The standard care of either strong cotton banding to edge of bed with medications as indicated and close observation or the other standard care of use of a minimally furnished seclusion room but with open but barred windows onto the nursing station. Outcomes-time to restrictions lifted, early change of treatment, additional episodes, adverse effects/events, satisfaction with care during episode. Duration-2 weeks. Identifier: ISRCTN 49454276 http://www.controlled-trials.com/ISRCTN49454276 PMID:21774823

  17. Functional changes in adipose tissue in a randomised controlled trial of physical activity

    PubMed Central

    2012-01-01

    Background A sedentary lifestyle predisposes to cardiometabolic diseases. Lifestyle changes such as increased physical activity improve a range of cardiometabolic risk factors. The objective of this study was to examine whether functional changes in adipose tissue were related to these improvements. Methods Seventy-three sedentary, overweight (mean BMI 29.9 ± 3.2 kg/m2) and abdominally obese, but otherwise healthy men and women (67.6 ± 0.5 years) from a randomised controlled trial of physical activity on prescription over a 6-month period were included (control n = 43, intervention n = 30). Detailed examinations were carried out at baseline and at follow-up, including fasting blood samples, a comprehensive questionnaire and subcutaneous adipose tissue biopsies for fatty acid composition analysis (n = 73) and quantification of mRNA expression levels of 13 candidate genes (n = 51), including adiponectin, leptin and inflammatory cytokines. Results At follow-up, the intervention group had a greater increase in exercise time (+137 min/week) and a greater decrease in body fat mass (−1.5 kg) compared to the control subjects (changes of 0 min/week and −0.5 kg respectively). Circulating concentrations of adiponectin were unchanged, but those of leptin decreased significantly more in the intervention group (−1.8 vs −1.1 ng/mL for intervention vs control, P < 0.05). The w6-polyunsaturated fatty acid content, in particular linoleic acid (18:2w6), of adipose tissue increased significantly more in the intervention group, but the magnitude of the change was small (+0.17 vs +0.02 percentage points for intervention vs control, P < 0.05). Surprisingly leptin mRNA levels in adipose tissue increased in the intervention group (+107% intervention vs −20% control, P < 0.05), but changes in expression of the remaining genes did not differ between the groups. Conclusions After a 6-month period of increased physical activity in

  18. Robust stability and performance of time-delay control systems.

    PubMed

    Keviczky, L; Bányász, Cs

    2007-04-01

    Most of the optimal and adaptive regulators assume an a priori known time delay. The time-delay mismatch can cause unwanted instability. Influence of this uncertainty is investigated in connection with the required performance and robustness.

  19. Robust Control of Uncertain Systems via Dissipative LQG-Type Controllers

    NASA Technical Reports Server (NTRS)

    Joshi, Suresh M.

    2000-01-01

    Optimal controller design is addressed for a class of linear, time-invariant systems which are dissipative with respect to a quadratic power function. The system matrices are assumed to be affine functions of uncertain parameters confined to a convex polytopic region in the parameter space. For such systems, a method is developed for designing a controller which is dissipative with respect to a given power function, and is simultaneously optimal in the linear-quadratic-Gaussian (LQG) sense. The resulting controller provides robust stability as well as optimal performance. Three important special cases, namely, passive, norm-bounded, and sector-bounded controllers, which are also LQG-optimal, are presented. The results give new methods for robust controller design in the presence of parametric uncertainties.

  20. Robustness, flexibility, and sensitivity in a multifunctional motor control model.

    PubMed

    Lyttle, David N; Gill, Jeffrey P; Shaw, Kendrick M; Thomas, Peter J; Chiel, Hillel J

    2017-02-01

    Motor systems must adapt to perturbations and changing conditions both within and outside the body. We refer to the ability of a system to maintain performance despite perturbations as "robustness," and the ability of a system to deploy alternative strategies that improve fitness as "flexibility." Different classes of pattern-generating circuits yield dynamics with differential sensitivities to perturbations and parameter variation. Depending on the task and the type of perturbation, high sensitivity can either facilitate or hinder robustness and flexibility. Here we explore the role of multiple coexisting oscillatory modes and sensory feedback in allowing multiphasic motor pattern generation to be both robust and flexible. As a concrete example, we focus on a nominal neuromechanical model of triphasic motor patterns in the feeding apparatus of the marine mollusk Aplysia californica. We find that the model can operate within two distinct oscillatory modes and that the system exhibits bistability between the two. In the "heteroclinic mode," higher sensitivity makes the system more robust to changing mechanical loads, but less robust to internal parameter variations. In the "limit cycle mode," lower sensitivity makes the system more robust to changes in internal parameter values, but less robust to changes in mechanical load. Finally, we show that overall performance on a variable feeding task is improved when the system can flexibly transition between oscillatory modes in response to the changing demands of the task. Thus, our results suggest that the interplay of sensory feedback and multiple oscillatory modes can allow motor systems to be both robust and flexible in a variable environment.

  1. Methodological considerations for a randomised controlled trial of podiatry care in rheumatoid arthritis: lessons from an exploratory trial

    PubMed Central

    Turner, Deborah E; Helliwell, Philip S; Woodburn, James

    2007-01-01

    Background Whilst evidence exists to support the use of single treatments such as orthoses and footwear, the effectiveness of podiatry-led care as a complex intervention for patients with rheumatoid arthritis (RA) related foot problems is unknown. The aim of this study was to undertake an exploratory randomised controlled parallel arm clinical trial (RheumAFooT) to inform the design and implementation of a definitive trial and to understand the potential benefits of this care. Methods Patients with a definite diagnosis of RA, stable drug management 3 months prior to entry, and a current history of foot problems (pain, deformity, stiffness, skin or nail lesions, or footwear problems) were recruited from a hospital outpatient rheumatology clinic and randomised to receive 12 months of podiatry treatment or no care. The primary outcome was change in foot health status using the impairment/footwear (LFISIF) and activity limitation/participation restriction (LFISAP) subscales of the Leeds Foot Impact Scale. Disease Activity Score (DAS), Health Assessment Questionnaire (HAQ) score and walking speed (m/s) were also recorded. Results Of the 80 patients identified, 64 patients were eligible to participate in the pilot and 34 were recruited. 16 patients were randomised to receive podiatry led foot care and 18 received no care. Against a backdrop of stable disease (DAS and HAQ scores), there was a statistically significant between group difference in the change in foot health status for foot impairment (LFISIF) but not activity/participation (LFISAP) or function (walking speed) over 12 months. In the podiatry arm, 1 patient declined treatment following randomisation (did not want additional hospital visits) and 3 self-withdrew (lost to follow-up). Patients received an average of 3 consultations for assessment and treatment comprising routine care for skin and nail lesions (n = 3), foot orthoses (n = 9), footwear referral to the orthotist (n = 5), and ultrasound guided intra

  2. Intelligent robust control for uncertain nonlinear time-varying systems and its application to robotic systems.

    PubMed

    Chang, Yeong-Chan

    2005-12-01

    This paper addresses the problem of designing adaptive fuzzy-based (or neural network-based) robust controls for a large class of uncertain nonlinear time-varying systems. This class of systems can be perturbed by plant uncertainties, unmodeled perturbations, and external disturbances. Nonlinear H(infinity) control technique incorporated with adaptive control technique and VSC technique is employed to construct the intelligent robust stabilization controller such that an H(infinity) control is achieved. The problem of the robust tracking control design for uncertain robotic systems is employed to demonstrate the effectiveness of the developed robust stabilization control scheme. Therefore, an intelligent robust tracking controller for uncertain robotic systems in the presence of high-degree uncertainties can easily be implemented. Its solution requires only to solve a linear algebraic matrix inequality and a satisfactorily transient and asymptotical tracking performance is guaranteed. A simulation example is made to confirm the performance of the developed control algorithms.

  3. Analysis and synthesis of HVDC controls for robust stability of power systems

    SciTech Connect

    Venkataraman, S.; Khammash, M.H.; Vittal, V.

    1995-11-01

    High Voltage DC (HVDC) links have controllable characteristics with potential for affecting system stability. This paper follows the robustness methodology procedure to analyze the stability robustness of HVDC controls in power systems over a range of operating conditions. A novel method to design power system controllers using the robustness methodology is also proposed. Numerical results for a sample test-system are obtained and compared with those obtained by conventional techniques.

  4. Injury risk in runners using standard or motion control shoes: a randomised controlled trial with participant and assessor blinding

    PubMed Central

    Malisoux, Laurent; Chambon, Nicolas; Delattre, Nicolas; Gueguen, Nils; Urhausen, Axel; Theisen, Daniel

    2016-01-01

    Background/aim This randomised controlled trial investigated if the usage of running shoes with a motion control system modifies injury risk in regular leisure-time runners compared to standard shoes, and if this influence depends on foot morphology. Methods Recreational runners (n=372) were given either the motion control or the standard version of a regular running shoe model and were followed up for 6 months regarding running activity and injury. Foot morphology was analysed using the Foot Posture Index method. Cox regression analyses were used to compare injury risk between the two groups, based on HRs and their 95% CIs, controlling for potential confounders. Stratified analyses were conducted to evaluate the effect of motion control system in runners with supinated, neutral and pronated feet. Results The overall injury risk was lower among the participants who had received motion control shoes (HR=0.55; 95% CI 0.36 to 0.85) compared to those receiving standard shoes. This positive effect was only observed in the stratum of runners with pronated feet (n=94; HR=0.34; 95% CI 0.13 to 0.84); there was no difference in runners with neutral (n=218; HR=0.78; 95% CI 0.44 to 1.37) or supinated feet (n=60; HR=0.59; 95% CI 0.20 to 1.73). Runners with pronated feet using standard shoes had a higher injury risk compared to those with neutral feet (HR=1.80; 95% CI 1.01 to 3.22). Conclusions The overall injury risk was lower in participants who had received motion control shoes. Based on secondary analysis, those with pronated feet may benefit most from this shoe type. PMID:26746907

  5. A modular robust control framework for control of movement elicited by multi-electrode intraspinal microstimulation

    NASA Astrophysics Data System (ADS)

    Roshani, Amir; Erfanian, Abbas

    2016-08-01

    Objective. An important issue in restoring motor function through intraspinal microstimulation (ISMS) is the motor control. To provide a physiologically plausible motor control using ISMS, it should be able to control the individual motor unit which is the lowest functional unit of motor control. By focal stimulation only a small group of motor neurons (MNs) within a motor pool can be activated. Different groups of MNs within a motor pool can potentially be activated without involving adjacent motor pools by local stimulation of different parts of a motor pool via microelectrode array implanted into a motor pool. However, since the system has multiple inputs with single output during multi-electrode ISMS, it poses a challenge to movement control. In this paper, we proposed a modular robust control strategy for movement control, whereas multi-electrode array is implanted into each motor activation pool of a muscle. Approach. The controller was based on the combination of proportional-integral-derivative and adaptive fuzzy sliding mode control. The global stability of the controller was guaranteed. Main results. The results of the experiments on rat models showed that the multi-electrode control can provide a more robust control and accurate tracking performance than a single-electrode control. The control output can be pulse amplitude (pulse amplitude modulation, PAM) or pulse width (pulse width modulation, PWM) of the stimulation signal. The results demonstrated that the controller with PAM provided faster convergence rate and better tracking performance than the controller with PWM. Significance. This work represents a promising control approach to the restoring motor functions using ISMS. The proposed controller requires no prior knowledge about the dynamics of the system to be controlled and no offline learning phase. The proposed control design is modular in the sense that each motor pool has an independent controller and each controller is able to control ISMS

  6. Sequential docetaxel as adjuvant chemotherapy for early breast cancer (TACT): an open-label, phase III, randomised controlled trial

    PubMed Central

    Ellis, Paul; Barrett-Lee, Peter; Johnson, Lindsay; Cameron, David; Wardley, Andrew; O'Reilly, Susan; Verrill, Mark; Smith, Ian; Yarnold, John; Coleman, Robert; Earl, Helena; Canney, Peter; Twelves, Chris; Poole, Christopher; Bloomfield, David; Hopwood, Penelope; Johnston, Stephen; Dowsett, Mitchell; Bartlett, John MS; Ellis, Ian; Peckitt, Clare; Hall, Emma; Bliss, Judith M

    2009-01-01

    Summary Background Incorporation of a taxane as adjuvant treatment for early breast cancer offers potential for further improvement of anthracycline-based treatment. The UK TACT study (CRUK01/001) investigated whether sequential docetaxel after anthracycline chemotherapy would improve patient outcome compared with standard chemotherapy of similar duration. Methods In this multicentre, open-label, phase III, randomised controlled trial, 4162 women (aged >18 years) with node-positive or high-risk node-negative operable early breast cancer were randomly assigned by computer-generated permuted block randomisation to receive FEC (fluorouracil 600 mg/m2, epirubicin 60 mg/m2, cyclophosphamide 600 mg/m2 at 3-weekly intervals) for four cycles followed by docetaxel (100 mg/m2 at 3-weekly intervals) for four cycles (n=2073) or control (n=2089). For the control regimen, centres chose either FEC for eight cycles (n=1265) or epirubicin (100 mg/m2 at 3-weekly intervals) for four cycles followed by CMF (cyclophosphamide 600 mg/m2, methotrexate 40 mg/m2, and fluorouracil 600 mg/m2 at 4-weekly intervals) for four cycles (n=824). The primary endpoint was disease-free survival. Analysis was by intention to treat (ITT). This study is registered as an International Standard Randomised Controlled Trial, number ISRCTN79718493. Findings All randomised patients were included in the ITT population. With a median follow-up of 62 months, disease-free survival events were seen in 517 of 2073 patients in the experimental group compared with 539 of 2089 controls (hazard ratio [HR] 0·95, 95% CI 0·85–1·08; p=0·44). 75·6% (95% CI 73·7–77·5) of patients in the experimental group and 74·3% (72·3–76·2) of controls were alive and disease-free at 5 years. The proportion of patients who reported any acute grade 3 or 4 adverse event was significantly greater in the experimental group than in the control group (p<0·0001); the most frequent events were neutropenia (937 events vs 797 events

  7. Melatonin premedication versus placebo in wisdom teeth extraction: a randomised controlled trial

    PubMed Central

    Seet, Edwin; Liaw, Chen Mei; Tay, Sylvia; Su, Chang

    2015-01-01

    INTRODUCTION Pain after wisdom teeth surgery can be moderate in severity and is compounded by preoperative anxiety in young patients. We studied the effect of melatonin premedication on postoperative pain and preoperative anxiety in patients undergoing wisdom teeth extractions. METHODS This randomised controlled trial recruited 76 patients at Khoo Teck Puat Hospital who were American Society of Anesthesiologists physical status I and II, aged 21 to 65 and scheduled to undergo elective extraction of all four wisdom teeth under general anaesthesia. Patients with a history of long-term use or allergy to melatonin were excluded. The patients received either 6 mg melatonin or a placebo 90 minutes before surgery. Visual analogue scale (VAS) scores at multiple time intervals for postoperative pain and preoperative anxiety, patient satisfaction and first-night sleep quality scores were obtained. Mixed-effects regression models were used for longitudinal analysis of VAS pain, anxiety and satisfaction scores. RESULTS Maximum VAS scores for pain and anxiety were 18.6 ± 19.1 mm at 60 minutes postoperatively and 26.2 ± 23.4 mm at 90 minutes preoperatively, respectively. After adjusting for gender, female patients who received melatonin had a faster rate of reduction of VAS pain (p = 0.020) and anxiety scores (p = 0.003) over time compared to the placebo group. No such effect was demonstrated in male patients. There was no significant difference in sleep quality or satisfaction scores. CONCLUSION Melatonin use did not consistently contribute to pain and anxiety amelioration in all patients. Our study demonstrated a positive effect in female patients, suggestive of sexual dimorphism. PMID:26702161

  8. Informing efficient randomised controlled trials: exploration of challenges in developing progression criteria for internal pilot studies

    PubMed Central

    Williamson, Paula R; Gamble, Carrol; O'Connell Francischetto, Elaine; Metcalfe, Chris; Davidson, Peter; Williams, Hywel; Blazeby, Jane M

    2017-01-01

    Objectives Designing studies with an internal pilot phase may optimise the use of pilot work to inform more efficient randomised controlled trials (RCTs). Careful selection of preagreed decision or ‘progression’ criteria at the juncture between the internal pilot and main trial phases provides a valuable opportunity to evaluate the likely success of the main trial and optimise its design or, if necessary, to make the decision not to proceed with the main trial. Guidance on the appropriate selection and application of progression criteria is, however, lacking. This paper outlines the key issues to consider in the optimal development and review of operational progression criteria for RCTs with an internal pilot phase. Design A structured literature review and exploration of stakeholders' opinions at a Medical Research Council (MRC) Hubs for Trials Methodology Research workshop. Key stakeholders included triallists, methodologists, statisticians and funders. Results There is considerable variation in the use of progression criteria for RCTs with an internal pilot phase, although 3 common issues predominate: trial recruitment, protocol adherence and outcome data. Detailed and systematic reporting around the decision-making process for stopping, amending or proceeding to a main trial is uncommon, which may hamper understanding in the research community about the appropriate and optimal use of RCTs with an internal pilot phase. 10 top tips for the development, use and reporting of progression criteria for internal pilot studies are presented. Conclusions Systematic and transparent reporting of the design, results and evaluation of internal pilot trials in the literature should be encouraged in order to facilitate understanding in the research community and to inform future trials. PMID:28213598

  9. Integrative medicine for subacute stroke rehabilitation: a study protocol for a multicentre, randomised, controlled trial

    PubMed Central

    Fang, Jianqiao; Chen, Lifang; Chen, Luni; Wang, Chao; Keeler, Crystal Lynn; Ma, Ruijie; Xu, Shouyu; Shen, Laihua; Bao, Yehua; Ji, Conghua

    2014-01-01

    Introduction Many patients with stroke receive integrative medicine in China, which includes the basic treatment of Western medicine and routine rehabilitation, in conjunction with acupuncture and Chinese medicine. The question of whether integrative medicine is efficacious for stroke rehabilitation is still controversial and very little research currently exists on the integrated approach for this condition. Consequently, we will conduct a multicentre, randomised, controlled, assessor-blinded clinical trial to assess the effectiveness of integrative medicine on stroke rehabilitation. Methods and analysis 360 participants recruited from three large Chinese medical hospitals in Zhejiang Province will be randomly divided into the integrative medicine rehabilitation (IMR) group and the conventional rehabilitation (CR) group in a 1:1 ratio. Participants in the IMR group will receive acupuncture and Chinese herbs in addition to basic Western medicine and rehabilitation treatment. The CR group will not receive acupuncture and Chinese herbal medicine. The assessment data will be collected at baseline, 4 and 8 weeks postrandomisation, and then at 12 weeks’ follow-up. The primary outcome is measured by the Modified Barthel Index. The secondary outcomes are the National Institutes of Health Stroke Scale (NIHSS), Fugl-Meyer Assessment, the mini-mental state examination and Montreal Cognitive, Hamilton's Depression Scale and Self-Rating Depression Scale, and the incidence of adverse events. Ethics and dissemination Ethical approval was obtained from ethics committees of three hospitals. The results will be disseminated in a peer-reviewed journal and presented at international congresses. The results will also be disseminated to patients by telephone, during follow-up calls inquiring on patient's post-study health status. Trial registration number Chinese Clinical Trial Register: ChiCTR-TRC-12001972, http://www.chictr.org/en/proj/show.aspx?proj=2561 PMID:25475247

  10. A randomised controlled trial of nurse-managed trial conclusion following early phase cancer trial participation.

    PubMed

    Cox, K; Wilson, E; Arthur, A; Elkan, R; Armstrong, S

    2005-07-11

    The effect of a nurse-managed intervention, for early phase cancer trial participants at trial conclusion, on psychosocial outcomes was evaluated at two cancer centres in the Midlands, England using a randomised controlled trial. It involved 117 patients who were participating in an early phase cancer clinical trial. It was a nurse-managed trial exit, which included a trial exit interview, trial feedback information leaflet and telephone follow-up compared with standard care at trial conclusion. Psychological distress at 1 week and 4-6 weeks post-trial conclusion, patient's knowledge and understanding and patient's satisfaction were assessed. The results showed there was no significant difference between the two groups regarding scores for anxiety and depression at time one and time two. There is some suggestion that the intervention reduced anxiety from trial conclusion to follow-up (P=0.27). Patients in both groups felt they had contributed to cancer research through trial participation. However, intervention patients were more likely to feel that they knew how the trial was going (P<0.001), knew how other people in the trial were doing (P=0.001), had all the feedback they needed about the trial they took part in (P<0.01) and knew how they would be followed up (P=0.02). Patient satisfaction with the intervention was high (median score=4.5 where 5 is greatest satisfaction). In conclusion, nurse-managed trial conclusion led to positive outcomes for patients who had recently completed a clinical trial.

  11. Comparison of methadone and buprenorphine for opiate detoxification (LEEDS trial): a randomised controlled trial

    PubMed Central

    Wright, Nat MJ; Sheard, Laura; Adams, Clive E; Rushforth, Bruno J; Harrison, Wendy; Bound, Nicole; Hart, Roger; Tompkins, Charlotte NE

    2011-01-01

    Background Many opiate users require prescribed medication to help them achieve abstinence, commonly taking the form of a detoxification regime. In UK prisons, drug users are nearly universally treated for their opiate use by primary care clinicians, and once released access GP services where 40% of practices now treat drug users. There is a paucity of evidence evaluating methadone and buprenorphine (the two most commonly prescribed agents in the UK) for opiate detoxification. Aim To evaluate whether buprenorphine or methadone help to achieve drug abstinence at completion of a reducing regimen for heroin users presenting to UK prison health care for detoxification. Design Open-label, pragmatic, randomised controlled trial in three prison primary healthcare departments in the north of England. Method Prisoners (n = 306) using illicit opiates were recruited and given daily sublingual buprenorphine or oral methadone, in the context of routine care, over a standard reduced regimen of not more than 20 days. The primary outcome measure was abstinence from illicit opiates at 8 days post detoxification, as indicated by urine test (self-report/clinical notes where urine sample was not feasible). Secondary outcomes were also recorded. Results Abstinence was ascertained for 73.7% at 8 days post detoxification (urine sample = 52.6%, self report = 15.2%, clinical notes = 5.9%). There was no statistically significant difference in the odds of achieving abstinence between methadone and buprenorphine (odds ratio [OR] = 1.69; 95% confidence interval [CI] = 0.81 to 3.51; P = 0.163). Abstinence was associated solely with whether or not the participant was still in prison at that time (15.22 times the odds; 95% CI = 4.19 to 55.28). The strongest association for lasting abstinence was abstinence at an earlier time point. Conclusion There is equal clinical effectiveness between methadone and buprenorphine in achieving abstinence from opiates at 8 days post detoxification within prison

  12. Cost effectiveness of day and inpatient psychiatric treatment: results of a randomised controlled trial.

    PubMed Central

    Creed, F.; Mbaya, P.; Lancashire, S.; Tomenson, B.; Williams, B.; Holme, S.

    1997-01-01

    OBJECTIVE: To compare direct and indirect costs of day and inpatient treatment of acute psychiatric illness. DESIGN: Randomised controlled trial with outcome and costs assessed over 12 months after the date of admission. SETTING: Teaching hospital in an inner city area. SUBJECTS: 179 patients with acute psychiatric illness referred for admission who were suitable for random allocation to day hospital or inpatient treatment. 77 (43%) patients had schizophrenia. INTERVENTIONS: Routine inpatient or day hospital treatment. MAIN OUTCOME MEASURES: Direct and indirect costs over 12 months, clinical symptoms, social functioning, and burden on relatives over the follow up period. RESULTS: Clinical and social outcomes were similar at 12 months, except that inpatients improved significantly faster than day patients and burden on relatives was significantly less in the day hospital group at one year. Median direct costs to the hospital were 1923 pounds (95% confidence interval 750 pounds to 3174 pounds) per patient less for day hospital treatment than inpatient treatment. Indirect costs were greater for day patients; when these were included, overall day hospital treatment was 2165 pounds cheaper than inpatient treatment (95% confidence interval of median difference 737 pounds to 3593 pounds). Including costs to informants when appropriate meant that day hospital treatment was 1994 pounds per patient cheaper (95% confidence interval 600 pounds to 3543 pounds). CONCLUSIONS: Day patient treatment is cheaper for the 30-40% of potential admissions that can be treated in this way. Carers of day hospital patients may bear additional costs. Carers of all patients with acute psychiatric illness are often themselves severely distressed at the time of admission, but day hospital treatment leads to less burden on carers in the long term. PMID:9161310

  13. Amiodarone prophylaxis for tachycardias after coronary artery surgery: a randomised, double blind, placebo controlled trial.

    PubMed Central

    Butler, J; Harriss, D R; Sinclair, M; Westaby, S

    1993-01-01

    BACKGROUND--Arrhythmias are a common cause of morbidity after cardiac surgery. This study assessed the efficacy of prophylactic amiodarone in reducing the incidence of atrial fibrillation or flutter and ventricular arrhythmias after coronary artery surgery. METHODS--A double blind, randomised, placebo controlled trial. 60 patients received a 24 hour intravenous infusion of amiodarone (15 mg/kg started after removal of the aortic cross clamp) followed by 200 mg orally three times daily for 5 days, and 60 patients received placebo. RESULTS--6 patients (10%) in the amiodarone group and 14 (23%) in the placebo group needed treatment for arrhythmias (95% confidence interval (95% CI) for the difference between groups was 0 to 26%, p = 0.05). The incidence of supraventricular tachycardia detected clinically and requiring treatment was lower in the amiodarone group (8% amiodarone v 20% placebo, 95% CI 0 to 24%, p = 0.07). The incidence detected by 24 hour Holter monitoring was similar (17% amiodarone v 20% placebo). Untreated arrhythmias in the amiodarone group were either clinically benign and undetected (n = 3) or the ventricular response rate was slow (n = 2). Age > 60 years was a positive risk factor for the development of supraventricular tachycardia in the amiodarone group but not in the placebo group. Fewer patients had episodes of ventricular tachycardia or fibrillation recorded on Holter monitoring in the amiodarone group (15% amiodarone v 33% placebo, 95% CI 3 to 33%, p = 0.02). Bradycardia (78% amiodarone v 48% placebo, 95% CI 14% to 46%, p < 0.005) and pauses (7% amiodarone v 0% placebo) occurred in more amiodarone treated patients. Bradycardia warranted discontinuation of treatment in one patient treated with amiodarone. CONCLUSIONS--The incidence of clinically significant tachyc