WorldWideScience

Sample records for relaxation thermal biofeedback

  1. Occupational stress, relaxation therapies, exercise and biofeedback.

    Science.gov (United States)

    Stein, Franklin

    2001-01-01

    Occupational stress is a widespread occurrence in the United States. It is a contributing factor to absenteeism, disease, injury and lowered productivity. In general stress management programs in the work place that include relaxation therapies, exercise, and biofeedback have been shown to reduce the physiological symptoms such as hypertension, and increase job satisfaction and job performance. Strategies to implement a successful stress management program include incorporating the coping activities into one's daily schedule, monitoring one's symptoms and stressors, and being realistic in setting up a schedule that is relevant and attainable. A short form of meditation, daily exercise program and the use of heart rate or thermal biofeedback can be helpful to a worker experiencing occupational stress.

  2. Design for relaxation during milk expression using biofeedback

    NARCIS (Netherlands)

    Feijs, L.M.G.; Kierkels, J.G.T.; Marcus, A.

    2013-01-01

    Many women experience difficulty expressing milk using a breast pump. A negative influence upon their success is stress, hampering the milk ejection reflex. We explore biofeedback to enhance relaxation during milk expression. We discuss context, the principles of biofeedback and the design of an

  3. The benefit of heart rate variability biofeedback and relaxation training in reducing trait anxiety†

    Science.gov (United States)

    Lee, Jieun; Kim, Jung K; Wachholtz, Amy

    2016-01-01

    Previous research studies have indicated that biofeedback treatment and relaxation techniques are effective in reducing psychological and physical symptoms (Hammond, 2005; Manzoni, G. M., Pagnini, F., Castelnuovo, G., & Molinari, E., 2008). However, dearth of studies has compared heart rate variability (HRV) biofeedback treatment and relaxation training to reduce trait anxiety. The objective of this study was to determine the effect of HRV biofeedback treatment and relaxation training in reducing trait anxiety compared to control group without any treatment using students in a science and engineering university of South Korea. For the present study, a total of 15 graduate students with moderate level of trait anxiety were recruited for 4 individual sessions every two weeks. They were randomly assigned into three groups: biofeedback treatment (n = 5), relaxation training (n = 5), and no treatment control group (n = 5). Our results revealed significant difference in change score of trait anxiety between the HRV biofeedback treatment and the no treatment control group. However, no significant difference was found between the relaxation training group and the no treatment control group. In addition, there was no significant difference between the HRV biofeedback treatment and the relaxation training. Results of the present study indicate that there is potential benefit in utilizing HRV biofeedback treatment for stress management programs and/or anxiety reduction treatment PMID:27099546

  4. Critique: Can Children with AD/HD Learn Relaxation and Breathing Techniques through Biofeedback Video Games?

    Science.gov (United States)

    Wright, Craig; Conlon, Elizabeth

    2009-01-01

    This article presents a critique on K. Amon and A. Campbell's "Can children with AD/HD learn relaxation and breathing techniques through biofeedback video games?". Amon and Campbell reported a successful trial of a commercially available biofeedback program, "The Wild Divine", in reducing symptoms of Attention-Deficit/Hyperactivity Disorder (ADHD)…

  5. Biofeedback relaxation for pain associated with continuous passive motion in Taiwanese patients after total knee arthroplasty.

    Science.gov (United States)

    Wang, Tsae-Jyy; Chang, Ching-Fen; Lou, Meei-Fang; Ao, Man-Kuan; Liu, Chiung-Chen; Liang, Shu-Yuan; Wu, Shu-Fang Vivienne; Tung, Heng-Hsing

    2015-02-01

    Effective pain management is crucial for patient recovery after total knee arthroplasty (TKA). Biofeedback therapy, which encourages relaxation and helps alleviate various conditions associated with stress, may help to decrease postoperative pain in patients undergoing TKA. A quasi- experimental design was used to investigate the efficacy of a biofeedback relaxation intervention in reducing pain associated with postoperative continuous passive motion (CPM) therapy. Sixty-six patients admitted to a general hospital in Taiwan for TKA were recruited and randomly assigned to the intervention or control group. The intervention group received biofeedback training twice daily for 5 days, concurrent with CPM therapy, whereas the control group did not receive the biofeedback intervention. Pain was measured using a numeric rating scale before and after each CPM therapy session on postoperative days 1 through 5. The CPM-elicited pain score was calculated by subtracting the pre-CPM pain score from the post-CPM pain score. Results of repeated-measures analysis of variance showed intervention group reported significantly less pain caused by CPM than did the control group (f = 29.70, p biofeedback relaxation, a non-invasive and non-pharmacological intervention, as a complementary treatment option for pain management in this population. © 2014 Wiley Periodicals, Inc.

  6. Conceptual Framework for Therapeutic Training with Biofeedback in Virtual Reality: First Evaluation of a Relaxation Simulator

    Science.gov (United States)

    Fominykh, Mikhail; Prasolova-Førland, Ekaterina; Stiles, Tore C.; Krogh, Anne Berit; Linde, Mattias

    2018-01-01

    This paper presents a concept for designing low-cost therapeutic training with biofeedback and virtual reality. We completed the first evaluation of a prototype--a mobile learning application for relaxation training, primarily for adolescents suffering from tension-type headaches. The system delivers visual experience on a head-mounted display. A…

  7. [The effect of EMG level by EMG biofeedback with progressive muscle relaxation training on tension headache].

    Science.gov (United States)

    Ro, U J; Kim, N C; Kim, H S

    1990-08-01

    The purpose of this study is to assess if EMG biofeedback training with progressive muscle relaxation training is effective in reducing the EMG level in patients with tension headaches. This study which lasted from 23 October to 30 December 1989, was conducted on 10 females who were diagnosed as patients with tension headaches and selected from among volunteers at C. University in Seoul. The process of the study was as follows: First, before the treatment, the baseline was measured for two weeks and the level of EMG was measured five times in five minutes. And then EMG biofeedback training was used for six weeks, 12 sessions in all, and progressive muscle relaxation was done at home by audio tape over eight weeks. Each session was composed of a 5-minute baseline, two 5-minute EMG biofeedback training periods and a 5-minute self-control stage. Each stage was followed by a five minute rest period. So each session took a total of 40 minutes. The EMG level was measured by EMG biofeedback (Autogenic-Cyborg: M 130 EMG module). The results were as follows: 1. The average age of the subjects was 44.1 years and the average history of headache was 10.6 years (range: 6 months-20 years). 2. The level of EMG was lowest between the third and the fourth week of the training except in Cases I and IV. 3. The patients began to show a nonconciliatory attitude at the first session of the fifth week of the training.

  8. Comparison of sensory modes of biofeedback in relaxation training of frontalis muscle.

    Science.gov (United States)

    Chen, W

    1981-12-01

    The purpose of this study was to compare the effectiveness of various sensory modes of EMG biofeedback to relaxation training of the frontalis muscle. 19 male and 29 female subjects were randomly selected from a pool of college volunteers. They were then randomly assigned 12 each to audiofeedback, visual feedback, audiovisual feedback, and no feedback groups. There were 11 20-min. sessions per subject. Subjects in the biofeedback groups were trained to reduce muscle tension voluntarily by utilizing Cyborg J33 EMG portable trainers. The subjects in the three feedback groups exhibited significantly lower muscle tension than did the subjects in the no-feedback control group. There were no significant differences in relaxation among the three feedback groups.

  9. Reducing Anxiety and Improving Academic Performance Through a Biofeedback Relaxation Training Program.

    Science.gov (United States)

    Aritzeta, Aitor; Soroa, Goretti; Balluerka, Nekane; Muela, Alexander; Gorostiaga, Arantxa; Aliri, Jone

    2017-09-01

    The aim of this study was to analyze the influence of a biofeedback relaxation training program on anxiety and academic performance. The program consisted of five biofeedback sessions coupled with three training activities focused on deep breathing, guided imagery, and muscle relaxation. The participants were second-year psychology undergraduates from the University of the Basque Country (UPV/EHU, northern Spain). The experimental group comprised 152 students (M age  = 19.6, SD = 0.74; 74% women) and the control group 81 students (M age   = 19.4, SD = 0.92; 71% women). Results showed that after participating in the program, students in the experimental group had lower levels of anxiety and increased academic performance. Furthermore, they scored lower on anxiety and higher on academic performance in comparison with the control subjects. This suggests that the inclusion of biofeedback training programs in educational contexts could be a way of reducing anxiety and improving academic performance. It may also deepen our understanding of the dynamic interplay between psychophysiological, cognitive, and emotional processes.

  10. Biofeedback-assisted relaxation training to decrease test anxiety in nursing students.

    Science.gov (United States)

    Prato, Catherine A; Yucha, Carolyn B

    2013-01-01

    Nursing students experiencing debilitating test anxiety may be unable to demonstrate their knowledge and have potential for poor academic performance. A biofeedback-assisted relaxation training program was created to reduce test anxiety. Anxiety was measured using Spielberger's Test Anxiety Inventory and monitoring peripheral skin temperature, pulse, and respiration rates during the training. Participants were introduced to diaphragmatic breathing, progressive muscle relaxation, and autogenic training. Statistically significant changes occurred in respiratory rates and skin temperatures during the diaphragmatic breathing session; respiratory rates and peripheral skin temperatures during progressive muscle relaxation session; respiratory and pulse rates, and peripheral skin temperatures during the autogenic sessions. No statistically significant difference was noted between the first and second TAI. Subjective test anxiety scores of the students did not decrease by the end of training. Autogenic training session was most effective in showing a statistically significant change in decreased respiratory and pulse rates and increased peripheral skin temperature.

  11. Biofeedback: Its Uses in Education.

    Science.gov (United States)

    Matthews, Doris B.

    This paper begins by defining biofeedback and describing some of the major biofeedback machines. An historical perspective is provided of research literature on the relationship of biofeedback and learning. Biofeedback and relaxation are discussed and research is cited for the use of biofeedback techniques in relaxation training with children. Two…

  12. A COMPARATIVE STUDY OF EFFICACY OF EMG BIO-FEEDBACK AND PROGRESSIVE MUSCULAR RELAXATION IN TENSION HEADACHE1

    Science.gov (United States)

    Gada, M.T.

    1984-01-01

    SUMMARY The aim of the present study was to find out efficacy of frontalis EMG Biofeedback therapy, deep muscular relaxation therapy and compare the efficacy of both in cases of tension headache. During two week basal-data recording period all patients were taught deep muscular relaxation by Jacobson′s technique. Simultaneously patients were instructed to keep headache diary. Headache diary yielded three different parameters a) number of headache-free days per week, b) peak headache intensity (or each week and c) average daily headache activity score per week. These parameters were used to find out therapeutic efficacy of each treatment. Patients were randomly divided in two groups. EMG Biofeedback group was given frontalis EMG feedback through EMG J 33 muscle trainer of Cyborg Corporation (U.S.A.). Patients in each group were given 20 sessions (two sessions per week); each session lasting 30 minutes. Patients were instructed to practice at least one 30 minute session of relaxation at home. The data were subjected to statistical calculation. The results indicate that frontalis EMG Biofeedback therapy and deep muscle relaxation therapy are significantly effective in cases of tension headache. Both treatments are equally effective. The findings are discussed in relation to Indian situation. PMID:21965970

  13. A comparative study of efficacy of emg bio-feedback and progressive muscular relaxation in tension headache.

    Science.gov (United States)

    Gada, M T

    1984-04-01

    The aim of the present study was to find out efficacy of frontalis EMG Biofeedback therapy, deep muscular relaxation therapy and compare the efficacy of both in cases of tension headache. During two week basal-data recording period all patients were taught deep muscular relaxation by Jacobson's technique. Simultaneously patients were instructed to keep headache diary. Headache diary yielded three different parameters a) number of headache-free days per week, b) peak headache intensity (or each week and c) average daily headache activity score per week. These parameters were used to find out therapeutic efficacy of each treatment. Patients were randomly divided in two groups. EMG Biofeedback group was given frontalis EMG feedback through EMG J 33 muscle trainer of Cyborg Corporation (U.S.A.). Patients in each group were given 20 sessions (two sessions per week); each session lasting 30 minutes. Patients were instructed to practice at least one 30 minute session of relaxation at home. The data were subjected to statistical calculation. The results indicate that frontalis EMG Biofeedback therapy and deep muscle relaxation therapy are significantly effective in cases of tension headache. Both treatments are equally effective. The findings are discussed in relation to Indian situation.

  14. The Feasibility of Using the BrightHearts Biofeedback-Assisted Relaxation Application for the Management of Pediatric Procedural Pain: A Pilot Study.

    Science.gov (United States)

    Burton, Karen L O; Morrow, Angela M; Beswick, Brooke V; Khut, George P

    2018-04-17

    The objective of this pilot study was to assess the acceptability and feasibility of using BrightHearts, a biofeedback-assisted relaxation application (app), in children undergoing painful procedures. Thirty children 7 to 18 years of age undergoing a medical procedure (peripheral blood collection, botulinum toxin injection, or intravenous cannula insertion) participated. Participants used BrightHearts, a heart rate-controlled biofeedback-assisted relaxation training app delivered via an iPad with heart rate measured through a pulse oximeter worn on the ear or thumb. Feasibility was assessed through observations and patient, parent/carer, and healthcare professional feedback. Patient, parent/carer, and healthcare professional satisfaction with BrightHearts was rated using investigator-developed surveys. Eighty-three percent of child participants reported that they found BrightHearts helpful during the procedure and that they would use BrightHearts again. All parents and 96% of healthcare professionals indicated they would use BrightHearts again. Sixty-four percent of healthcare providers perceived that BrightHearts assisted with the ease of performing the procedure. Qualitative analyses found 2 themes: (1) BrightHearts calms through providing distraction and biofeedback and (2) the impact of BrightHearts on the procedure. This pilot study demonstrates the feasibility of using biofeedback-assisted relaxation delivered via the BrightHearts app in children undergoing peripheral blood collection and cannulation. Future studies are required to evaluate BrightHearts' efficacy in reducing pain and anxiety during painful procedures and distinguish the effects of a biofeedback-mediated app from distraction. © 2018 World Institute of Pain.

  15. Stress relaxation of thermally bowed fuel pins

    International Nuclear Information System (INIS)

    Crossland, I.G.; Speight, M.V.

    1983-01-01

    The presence of cross-pin temperature gradients in nuclear reactor fuel pins produces differential thermal expansion which, in turn, causes the fuel pin to bow elastically. If the pin is restrained in any way, such thermal bowing causes the pin to be stressed. At high temperatures these stresses can relax by creep and it is shown here that this causes the pin to suffer an additional permanent deflection, so that when the cross-pin temperature difference is removed the pin remains bowed. By representing the cylindrical pin by an equivalent I-beam, the present work examines this effect when it takes place by secondary creep. Two restraint systems are considered, and it is demonstrated that the rate of relaxation depends mainly upon the creep equation, and hence the temperature, and also the magnitude of the initial stresses. (author)

  16. Thermal relaxation of charm in hadronic matter

    Energy Technology Data Exchange (ETDEWEB)

    He Min, E-mail: mhe@comp.tamu.edu [Cyclotron Institute and Department of Physics and Astronomy, Texas A and M University, College Station, TX 77843 (United States); Fries, Rainer J. [Cyclotron Institute and Department of Physics and Astronomy, Texas A and M University, College Station, TX 77843 (United States); RIKEN/BNL Research Center, Brookhaven National Laboratory, Upton, NY 11973 (United States); Rapp, Ralf [Cyclotron Institute and Department of Physics and Astronomy, Texas A and M University, College Station, TX 77843 (United States)

    2011-07-18

    The thermal relaxation rate of open-charm (D) mesons in hot and dense hadronic matter is calculated using empirical elastic scattering amplitudes. D-meson interactions with thermal pions are approximated by D{sup *} resonances, while scattering off other hadrons (K, {eta}, {rho}, {omega}, K{sup *}, N, {Delta}) is evaluated using vacuum scattering amplitudes as available in the literature based on effective Lagrangians and constrained by realistic spectroscopy. The thermal relaxation time of D-mesons in a hot {pi} gas is found to be around 25-50 fm/c for temperatures T=150-180 MeV, which reduces to 10-25 fm/c in a hadron-resonance gas. The latter values, argued to be conservative estimates, imply significant modifications of D-meson spectra in heavy-ion collisions. Close to the critical temperature (T{sub c}), the spatial diffusion coefficient (D{sub s}) is surprisingly similar to recent calculations for charm quarks in the Quark-Gluon Plasma using non-perturbative T-matrix interactions. This suggests a possibly continuous minimum structure of D{sub s} around T{sub c}.

  17. Structural relaxation and thermal conductivity coefficient of liquids

    International Nuclear Information System (INIS)

    Abdurasulov, A.

    1992-01-01

    Present article is devoted to structural relaxation and thermal conductivity coefficient of liquids. The thermoelastic properties of liquids were studied taking into account the contribution of translational and structural relaxation. The results of determination of dynamic coefficient of thermal conductivity of liquids taking into account the contribution of translational and structural relaxation are presented.

  18. Thermal stress relaxation in magnesium composites during thermal cycling

    Energy Technology Data Exchange (ETDEWEB)

    Trojanova, Z.; Lukac, P. (Karlova Univ., Prague (Czech Republic)); Kiehn, J.; Kainer, K.U.; Mordike, B.L. (Technische Univ. Clausthal, Clausthal-Zellerfeld (Germany))

    1998-01-01

    It has been shown that the internal friction of Mg - Saffil metal matrix composites can be influenced by thermal stresses, if MMCc are submitted to thermal cycling between room temperature and an upper temperature of cycling. These stresses can be accommodated by generation and motion of dislocations giving the formation of the microplastic zones. The thermal stress relaxation depends on the upper temperature of cycling, the volume fraction of reinforcement and the matrix composition and can result in plastic deformation and strain hardening of the matrix without applied stress. The internal friction measurements can be used for non destructive investigation of processes which influence the mechanical properties. (orig.)

  19. Biofeedback, autogenic training, and progressive relaxation in the treatment of Raynaud's disease: a comparative study.

    Science.gov (United States)

    Keefe, F J; Surwit, R S; Pilon, R N

    1980-01-01

    Twenty-one female patients suffering from diagnosed idiopathic Raynaud's Disease were trained to raise digital skin temperature using either autogenic training, progressive muscle relaxation, or a combination of autogenic training and skin temperature feedback. Patients were instructed in the treatment procedures in three one-hour group sessions spaced one week apart. All patients were instructed to practice what they had learned twice a day at home. Patients kept records of the frequency of vasospastic attacks occurring over a four-week baseline period, and during the first four weeks and the ninth week of training. In addition, patients underwent four laboratory cold stress tests during which they were instructed to maintain digital temperature as the ambient temperature was slowly dropped from 26 degrees to 17 degrees C. Cold stress tests were given during week 1 of baseline and during weeks 1, 3, and 5 of training. No significant differences between the three behavioral treatment procedures were obtained. In addition, the ability of patients to maintain digital temperature during the cold stress challenge showed significant improvement from the first to the last tests. Symptomatic improvement was maintained by all patients nine weeks after the start of training. The implications of these findings for the behavioral treatment of Raynaud's Disease are discussed. PMID:6988380

  20. Biofeedback and Performance: An Update

    Science.gov (United States)

    1984-12-01

    non-biofeedback meditation procedure; a single control was a group untrained in relaxation. It is not clear what instructions if any were given to...found in techniques to control motion sickness. Using a procedure they call " autogenic biofeedback training (AFT)", investigators at NASA (Cowings...and meditation in the treatment of generalized anxiety. Proceedings of the 14th Annual Meeting of the Biofeedback Society of America, 187-189

  1. Biofeedback: Infant asthma Biofeedback: asma infantil

    Directory of Open Access Journals (Sweden)

    J. J. Nombela

    2010-09-01

    Full Text Available

    The present study is a revision of the different applications of biofeedback in infantile bronchial asthma. The technique may be used on its own (preferably in the motor area or in conjunction with other techniques such as hypnosis, relaxation, etc. However, it should be stated that previous work published in this field is difficult to interpret since results are inconclusive, it is, therefore, difficult to produce a scientific summary.

    KEY WORDS: Biofeedback; infantile asthma; respiratory biofeedback.

    Con este trabajo se pretende hacer una revisión sobre las distintas aplicaciones del biofeedback en el asma bronquial infantil, bien solo (preferentemente en el campo motriz o bien asociado a otras técnicas de hipnosis, relajación, etc. Aunque es necesario manifestar que la producción científica relacionada con el tema, hace que tenga una difícil valoración dado que sus resultados son no concluyentes y discutibles, lo cual dificulta la elaboración de un resumen científico.
    PALABRAS CLAVE: Biofeedback; asma infantil; biofeedback respiratorio

  2. EEG biofeedback

    OpenAIRE

    Dvořáček, Michael

    2010-01-01

    Vznik EEG aktivity v mozku, rozdělení EEG vln podle frekvence, způsob měření EEG, přístroje pro měření EEG. Dále popis biofeedback metody, její možnosti a návrh biofeedback her. Popis zpracování naměřených EEG signálů. EEG generation, brain rhythms, methods of recording EEG, EEG recorder. Description of biofeedback, potentialities of biofeedback, proposal of biofeedback games. Description of processing measured EEG signals. B

  3. Stress Management by Biofeedback

    Science.gov (United States)

    1997-01-01

    In the 1980's, Dr. Patrick Doyle served on a project to train U.S. astronauts at Johnson Space Center in biofeedback techniques to control anxiety and hypertension. Traditional biofeedback concepts were found to be too mundane, repetitive and boring, so Doyle developed Bio-Games with more interesting and involved formats. The first product, Bio-Ball, is an interactive, multimedia baseball video game that is played by relaxing in order to hit the ball. Gradually the player is able to relax at will, and with practice is able to apply the skills to real-life situations. Doyle has since gone on to create a number of biofeedback games marketed by Creative MultiMedia Inc. including Bio-Golf, Clutch City, and Pachyderm. Stress-busting screen savers are also being marketed under the Buddies series. In addition to being used in the corporate world, Bio-Games have been recognized by the Starbright Foundation which focuses on improving the total hospital environments of critically injured and chronically-ill children.

  4. ESTIMATION OF THERMAL PARAMETERS OF POWER BIPOLAR TRANSISTORS BY THE METHOD OF THERMAL RELAXATION DIFFERENTIAL SPECTROMETRY

    Directory of Open Access Journals (Sweden)

    V. S. Niss

    2015-01-01

    Full Text Available Thermal performance of electronic devices determines the stability and reliability of the equipment. This leads to the need for a detailed thermal analysis of semiconductor devices. The goal of the work is evaluation of thermal parameters of high-power bipolar transistors in plastic packages TO-252 and TO-126 by a method of thermal relaxation differential spectrometry. Thermal constants of device elements and distribution structure of thermal resistance defined as discrete and continuous spectra using previously developed relaxation impedance spectrometer. Continuous spectrum, based on higher-order derivatives of the dynamic thermal impedance, follows the model of Foster, and discrete to model of Cauer. The structure of sample thermal resistance is presented in the form of siх-chain electro-thermal RC model. Analysis of the heat flow spreading in the studied structures is carried out on the basis of the concept of thermal diffusivity. For transistor structures the area and distribution of the heat flow cross-section are determined. On the basis of the measurements the thermal parameters of high-power bipolar transistors is evaluated, in particular, the structure of their thermal resistance. For all of the measured samples is obtained that the thermal resistance of the layer planting crystal makes a defining contribution to the internal thermal resistance of transistors. In the transition layer at the border of semiconductor-solder the thermal resistance increases due to changes in the mechanism of heat transfer. Defects in this area in the form of delamination of solder, voids and cracks lead to additional growth of thermal resistance caused by the reduction of the active square of the transition layer. Method of thermal relaxation differential spectrometry allows effectively control the distribution of heat flow in high-power semiconductor devices, which is important for improving the design, improve the quality of landing crystals of power

  5. Spin current relaxation time in thermally evaporated pentacene films

    OpenAIRE

    Tani, Yasuo; Kondo, Takuya; Teki, Yoshio; Shikoh, Eiji

    2017-01-01

    The spin current relaxation time [tau] in thermally evaporated pentacene films was evaluated with the spin-pump-induced spin transport properties and the charge current transport properties in pentacene films. Under an assumption of a diffusive transport of the spin current in pentacene films, the zero-field mobility and the diffusion constant of holes in pentacene films were experimentally obtained to be ~8.0x10^-7 m^2/Vs and ~2.0x10^-8 m^2/s, respectively. Using those values and the previou...

  6. Structure and low temperature thermal relaxation of amorphized germanium

    International Nuclear Information System (INIS)

    Glover, C.J.; Ridgway, M.C.; Byrne, A.P.; Clerc, C.; Hansen, J.L.; Larsen, A.N.

    1999-01-01

    The structure of implantation-induced damage in amorphized Ge has been investigated using high resolution extended x-ray absorption fine structure spectroscopy (EXAFS). EXAFS data analysis was performed with the Cumulant Method, allowing a full reconstruction of the interatomic distance distribution (RDF). For the case of MeV implantation at -196 deg C, for an ion-dose range extending two orders of magnitude beyond that required for amorphization, a dose-dependent asymmetric RDF was determined for the amorphous phase including an increase in bond-length as a function of ion dose. Low-temperature thermal annealing resulted in structural relaxation of the amorphous phase as evidenced by a reduction in the centroid, asymmetry and width of the RDF. Such an effect was attributed to the formation (and subsequent annihilation) of three- and five-fold Co-ordinated atoms, comparing favourably to theoretical simulations of the structure of a-Ge

  7. EMG biofeedback of the abductor pollicis brevis in piano performance.

    Science.gov (United States)

    Montes, R; Bedmar, M; Sol Martin, M

    1993-06-01

    The aim of the present study was to apply EMG biofeedback as an auxiliary to piano teaching techniques. We studied the changes in integrated electromyographic activity, using the abductor pollicis brevis functioning as an agonist during the teaching of identical selective movements of piano playing in two groups, one with EMG biofeedback and the other following traditional method of instruction. The analysis of variance revealed an increase in the peak amplitude and the relaxation rate values for the biofeedback group. These results have implications for the application of piano playing techniques and reveal EMG biofeedback as an aid in the teaching of thumb attack with the abductor pollicis brevis as agonist.

  8. Biofeedback training in chronic constipation.

    Science.gov (United States)

    Benninga, M A; Büller, H A; Taminiau, J A

    1993-01-01

    Twenty nine patients, aged 5-16 years, were studied to evaluate whether biofeedback training is effective in treating children with chronic constipation and encopresis; the clinical outcome at six weeks and 12 months was also evaluated. Patients received on average five biofeedback training sessions. The existence of external anal contraction or decreased rectal sensation in 16 (55%) and eight (27%) of the children, respectively was identified on manometry. After biofeedback training, 26 (90%) of the patients learned to relax the external anal sphincter; 18 (63%) normalised rectal sensation. The training resulted in a significant increase in defecation frequency and a significant decrease in encopresis. At six weeks, 16 (55%) of the patients were clinically symptom free. At follow up after 12 months the results were sustained. Only three patients showed a relapse within six months, of whom two were successfully treated with one extra training session. Biofeedback training might be a useful therapeutical approach in children with chronic constipation and encopresis. PMID:8434996

  9. Entanglement, decoherence and thermal relaxation in exactly solvable models

    International Nuclear Information System (INIS)

    Lychkovskiy, Oleg

    2011-01-01

    Exactly solvable models provide an opportunity to study different aspects of reduced quantum dynamics in detail. We consider the reduced dynamics of a single spin in finite XX and XY spin 1/2 chains. First we introduce a general expression describing the evolution of the reduced density matrix. This expression proves to be tractable when the combined closed system (i.e. open system plus environment) is integrable. Then we focus on comparing decoherence and thermalization timescales in the XX chain. We find that for a single spin these timescales are comparable, in contrast to what should be expected for a macroscopic body. This indicates that the process of quantum relaxation of a system with few accessible states can not be separated in two distinct stages - decoherence and thermalization. Finally, we turn to finite-size effects in the time evolution of a single spin in the XY chain. We observe three consecutive stages of the evolution: regular evolution, partial revivals, irregular (apparently chaotic) evolution. The duration of the regular stage is proportional to the number of spins in the chain. We observe a 'quiet and cold period' in the end of the regular stage, which breaks up abruptly at some threshold time.

  10. Incontinence Treatment: Biofeedback

    Science.gov (United States)

    ... Treatment Lifestyle Changes Dietary Tips Medication Bowel Management Biofeedback Surgical Treatments Newer Treatment Options Tips on Finding ... Treatment Lifestyle Changes Dietary Tips Medication Bowel Management Biofeedback Surgical Treatments Newer Treatment Options Tips on Finding ...

  11. Biofeedback in rehabilitation.

    Science.gov (United States)

    Giggins, Oonagh M; Persson, Ulrik McCarthy; Caulfield, Brian

    2013-06-18

    This paper reviews the literature relating to the biofeedback used in physical rehabilitation. The biofeedback methods used in rehabilitation are based on biomechanical measurements and measurements of the physiological systems of the body. The physiological systems of the body which can be measured to provide biofeedback are the neuromuscular system, the respiratory system and the cardiovascular system. Neuromuscular biofeedback methods include electromyography (EMG) biofeedback and real-time ultrasound imaging (RTUS) biofeedback. EMG biofeedback is the most widely investigated method of biofeedback and appears to be effective in the treatment of many musculoskeletal conditions and in post cardiovascular accident (CVA) rehabilitation. RTUS biofeedback has been demonstrated effective in the treatment of low back pain (LBP) and pelvic floor muscle dysfunction. Cardiovascular biofeedback methods have been shown to be effective in the treatment of a number of health conditions such as hypertension, heart failure, asthma, fibromyalgia and even psychological disorders however a systematic review in this field has yet to be conducted. Similarly, the number of large scale studies examining the use of respiratory biofeedback in rehabilitation is limited. Measurements of movement, postural control and force output can be made using a number of different devices and used to deliver biomechanical biofeedback. Inertial based sensing biofeedback is the most widely researched biomechanical biofeedback method, with a number of studies showing it to be effective in improving measures of balance in a number of populations. Other types of biomechanical biofeedback include force plate systems, electrogoniometry, pressure biofeedback and camera based systems however the evidence for these is limited. Biofeedback is generally delivered using visual displays, acoustic or haptic signals, however more recently virtual reality (VR) or exergaming technology have been used as biofeedback

  12. The Response of Hyperkinesis to EMG Biofeedback.

    Science.gov (United States)

    Haight, Maryellen J.; And Others

    A study was conducted involving eight hyperkinetic males (11-15 years old) to determine if Ss receiving electromyography (EMG) biofeedback training would show a reduction in frontalis muscle tension, hyperactivity, and lability, and increases in self-esteem and visual and auditory attention span. Individual 45- and 30-minute relaxation exercises…

  13. Thermal relaxation of molecular oxygen in collisions with nitrogen atoms

    Energy Technology Data Exchange (ETDEWEB)

    Andrienko, Daniil A., E-mail: daniila@umich.edu; Boyd, Iain D. [Department of Aerospace Engineering, University of Michigan, 1320 Beal Ave., Ann Arbor, Michigan 48108 (United States)

    2016-07-07

    Investigation of O{sub 2}–N collisions is performed by means of the quasi-classical trajectory method on the two lowest ab initio potential energy surfaces at temperatures relevant to hypersonic flows. A complete set of bound–bound and bound–free transition rates is obtained for each precollisional rovibrational state. Special attention is paid to the vibrational and rotational relaxations of oxygen as a result of chemically non-reactive interaction with nitrogen atoms. The vibrational relaxation of oxygen partially occurs via the formation of an intermediate NO{sub 2} complex. The efficient energy randomization results in rapid vibrational relaxation at low temperatures, compared to other molecular systems with a purely repulsive potential. The vibrational relaxation time, computed by means of master equation studies, is nearly an order of magnitude lower than the relaxation time in N{sub 2}–O collisions. The rotational nonequilibrium starts to play a significant effect at translational temperatures above 8000 K. The present work provides convenient relations for the vibrational and rotational relaxation times as well as for the quasi-steady dissociation rate coefficient and thus fills a gap in data due to a lack of experimental measurements for this system.

  14. Thermally induced magnetic relaxation in square artificial spin ice

    Science.gov (United States)

    Andersson, M. S.; Pappas, S. D.; Stopfel, H.; Östman, E.; Stein, A.; Nordblad, P.; Mathieu, R.; Hjörvarsson, B.; Kapaklis, V.

    2016-11-01

    The properties of natural and artificial assemblies of interacting elements, ranging from Quarks to Galaxies, are at the heart of Physics. The collective response and dynamics of such assemblies are dictated by the intrinsic dynamical properties of the building blocks, the nature of their interactions and topological constraints. Here we report on the relaxation dynamics of the magnetization of artificial assemblies of mesoscopic spins. In our model nano-magnetic system - square artificial spin ice - we are able to control the geometrical arrangement and interaction strength between the magnetically interacting building blocks by means of nano-lithography. Using time resolved magnetometry we show that the relaxation process can be described using the Kohlrausch law and that the extracted temperature dependent relaxation times of the assemblies follow the Vogel-Fulcher law. The results provide insight into the relaxation dynamics of mesoscopic nano-magnetic model systems, with adjustable energy and time scales, and demonstrates that these can serve as an ideal playground for the studies of collective dynamics and relaxations.

  15. Biofeedback and Self-Regulation in Essential Hypertension.

    Science.gov (United States)

    1977-09-20

    SI n.c... ~ y aid ld.ruity by Mock numb.,) Biofeedback Operant condition ing Behav i oral factors in hypertension Re l axa ti on Meditation • 20...preliminary findings of a clini- cal study in which two types of biofeedback training were compared to a form of meditation in the treatment of borderline...behav ioral methods not involving the use of complex feedback techniques include progressive relaxation, medita- tion, yogic practices, autogenic

  16. Interface bond relaxation on the thermal conductivity of Si/Ge core-shell nanowires

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Weifeng; He, Yan; Ouyang, Gang, E-mail: gangouy@hunnu.edu.cn [Key Laboratory of Low-Dimensional Quantum Structures and Quantum Control of Ministry of Education, Synergetic Innovation Center for Quantum Effects and Applications(SICQEA), Hunan Normal University, Changsha 410081 (China); Sun, Changqing [School of Electrical & Electronic Engineering, Nanyang Technological University, Singapore 639798 (Singapore)

    2016-01-15

    The thermal conductivity of Si/Ge core-shell nanowires (CSNWs) is investigated on the basis of atomic-bond-relaxation consideration and continuum mechanics. An analytical model is developed to clarify the interface bond relaxation of Si/Ge CSNWs. It is found that the thermal conductivity of Si core can be modulated through covering with Ge epitaxial layers. The change of thermal conductivity in Si/Ge CSNWs should be attributed to the surface relaxation and interface mismatch between inner Si nanowire and outer Ge epitaxial layer. Our results are in well agreement with the experimental measurements and simulations, suggesting that the presented method provides a fundamental insight of the thermal conductivity of CSNWs from the atomistic origin.

  17. Biofeedback for Better Vision

    Science.gov (United States)

    1990-01-01

    Biofeedtrac, Inc.'s Accommotrac Vision Trainer, invented by Dr. Joseph Trachtman, is based on vision research performed by Ames Research Center and a special optometer developed for the Ames program by Stanford Research Institute. In the United States, about 150 million people are myopes (nearsighted), who tend to overfocus when they look at distant objects causing blurry distant vision, or hyperopes (farsighted), whose vision blurs when they look at close objects because they tend to underfocus. The Accommotrac system is an optical/electronic system used by a doctor as an aid in teaching a patient how to contract and relax the ciliary body, the focusing muscle. The key is biofeedback, wherein the patient learns to control a bodily process or function he is not normally aware of. Trachtman claims a 90 percent success rate for correcting, improving or stopping focusing problems. The Vision Trainer has also proved effective in treating other eye problems such as eye oscillation, cross eyes, and lazy eye and in professional sports to improve athletes' peripheral vision and reaction time.

  18. Thermal stresses in long prisms by relaxation methods

    Energy Technology Data Exchange (ETDEWEB)

    Cummins, J D [Atomic Energy Establishment, Winfrith, Dorchester, Dorset (United Kingdom)

    1959-07-15

    A general method is presented for calculating the elastic thermal stresses in long prisms which are producing heat and are not solvable by simple analytical methods. The problem of an inverted lattice i.e. an hexagonal coolant passage surrounded by hexagonal fuel elements is considered and the temperature and principal thermal stress distributions evaluated for the particular case of 20% coolant. The maximum thermal stress for this type of fuel element is about the same as the maximum thermal stress in a cylindrical fuel element surrounded by a sea of coolant assuming the existence of the same maximum temperature drop and material properties. (author)

  19. Thermal stresses in long prisms by relaxation methods

    International Nuclear Information System (INIS)

    Cummins, J.D.

    1959-07-01

    A general method is presented for calculating the elastic thermal stresses in long prisms which are producing heat and are not solvable by simple analytical methods. The problem of an inverted lattice i.e. an hexagonal coolant passage surrounded by hexagonal fuel elements is considered and the temperature and principal thermal stress distributions evaluated for the particular case of 20% coolant. The maximum thermal stress for this type of fuel element is about the same as the maximum thermal stress in a cylindrical fuel element surrounded by a sea of coolant assuming the existence of the same maximum temperature drop and material properties. (author)

  20. Impact of biofeedback on self-efficacy and stress reduction in obesity: a randomized controlled pilot study.

    Science.gov (United States)

    Teufel, Martin; Stephan, Kerstin; Kowalski, Axel; Käsberger, Saskia; Enck, Paul; Zipfel, Stephan; Giel, Katrin E

    2013-09-01

    Biofeedback application is an evidence-based technique to induce relaxation. A primary mechanism of action is the improvement of self-efficacy, which is needed to facilitate the translation of health behavioral intentions into action. Obesity is often associated with low self-efficacy and dysfunctional eating patterns, including comfort eating as an inexpedient relaxation technique. This is the first study investigating the effects of biofeedback on self-efficacy and relaxation in obesity. In the present experiment, 31 women, mean body mass index 35.5 kg/m², were randomized to a food-specific biofeedback paradigm, a non-specific relaxation biofeedback paradigm, or a waiting list control. Eight sessions of biofeedback of the electrodermal activity were performed while presenting either a challenging food stimulus or a non-specific landscape stimulus. Self-efficacy, stress, ability to relax, eating behavior, and electrodermal activity were assessed before, directly after, and 3 months after the intervention. The food-specific biofeedback predominantly showed effects on food-related self-efficacy and perceived stress. The non-specific relaxation biofeedback showed effects on the ability to relax. Self-reported improvements were confirmed by corresponding decrease in the electrodermal reaction to food stimuli. Biofeedback treatment is effective in improving self-efficacy in individuals with obesity and might therefore be a valuable additional intervention in obesity treatment.

  1. Hysteresis in magnetic materials: the role of structural disorder, thermal relaxation, and dynamic effects

    International Nuclear Information System (INIS)

    Bertotti, G.; Basso, V.; Beatrice, C.; LoBue, M.; Magni, A.; Tiberto, P.

    2001-01-01

    An overview is given of the present understanding of hysteresis phenomena in magnetic materials. The problem is addressed from three approximate viewpoints: the connection between rate-independent hysteresis and micromagnetics; the modifications brought into this picture by thermal relaxation effects; the role of rate-dependent magnetization mechanisms, like eddy-current-damped domain wall motion

  2. Outlet obstruction constipation (anismus) managed by biofeedback.

    Science.gov (United States)

    Kawimbe, B M; Papachrysostomou, M; Binnie, N R; Clare, N; Smith, A N

    1991-10-01

    Fifteen subjects presenting with intractable constipation due to obstructive defecation, mean (SEM) duration 8.8 (1.8) years, had the inappropriate contraction and electromyographic changes in the pelvic floor muscles and external and sphincter typical of this condition. An electromyographically derived index was used to grade its severity. A self applied biofeedback device was used to allow electromyographic recording of the abnormal external anal sphincter. The subjects were encouraged to reduce the abnormal electromyographic activity on straining after instruction and training. The procedure was intended as a relearning process in which the non-relaxing activity of the pelvic floor was gradually suppressed. Biofeedback training was maintained on a domiciliary basis for a mean time of 3.1 weeks and resulted in a significant reduction in the anismus index (mean (SEM) 69.9 (7.8)% before biofeedback, mean 14 (3.9)% after biofeedback, p less than 0.01). There was an associated reduction in the time spent straining at stool and in the difficulty of defecation and an increased frequency of defecation. Defecatory video proctograms in six subjects showed improvements in the anorectal angle during straining and evacuation. The clinical benefit to the patients persisted after a mean follow up of 6.2 months.

  3. Biofeedback and stuttering

    Directory of Open Access Journals (Sweden)

    E. Gordon

    1981-11-01

    Full Text Available Electromyographic biofeedback was used to reduce tension and enhance control of the speech associated muscles, resulting in a reduction of the frequency of stuttering. Five sessions were conducted over a course of three weeks. A mild, moderate and severe stutterer were assessed. A decrease in stuttering frequency was seen in each subject from pre to post biofeedback sessions on both a descriptive and an inferential level.

  4. Neurofeedback and biofeedback with 37 migraineurs: a clinical outcome study

    Directory of Open Access Journals (Sweden)

    Lappin Martha S

    2010-02-01

    Full Text Available Abstract Background Traditional peripheral biofeedback has grade A evidence for effectively treating migraines. Two newer forms of neurobiofeedback, EEG biofeedback and hemoencephalography biofeedback were combined with thermal handwarming biofeedback to treat 37 migraineurs in a clinical outpatient setting. Methods 37 migraine patients underwent an average of 40 neurofeedback sessions combined with thermal biofeedback in an outpatient biofeedback clinic. All patients were on at least one type of medication for migraine; preventive, abortive or rescue. Patients kept daily headache diaries a minimum of two weeks prior to treatment and throughout treatment showing symptom frequency, severity, duration and medications used. Treatments were conducted an average of three times weekly over an average span of 6 months. Headache diaries were examined after treatment and a formal interview was conducted. After an average of 14.5 months following treatment, a formal interview was conducted in order to ascertain duration of treatment effects. Results Of the 37 migraine patients treated, 26 patients or 70% experienced at least a 50% reduction in the frequency of their headaches which was sustained on average 14.5 months after treatments were discontinued. Conclusions All combined neuro and biofeedback interventions were effective in reducing the frequency of migraines with clients using medication resulting in a more favorable outcome (70% experiencing at least a 50% reduction in headaches than just medications alone (50% experience a 50% reduction and that the effect size of our study involving three different types of biofeedback for migraine (1.09 was more robust than effect size of combined studies on thermal biofeedback alone for migraine (.5. These non-invasive interventions may show promise for treating treatment-refractory migraine and for preventing the progression from episodic to chronic migraine.

  5. Neurofeedback and biofeedback with 37 migraineurs: a clinical outcome study

    Science.gov (United States)

    2010-01-01

    Background Traditional peripheral biofeedback has grade A evidence for effectively treating migraines. Two newer forms of neurobiofeedback, EEG biofeedback and hemoencephalography biofeedback were combined with thermal handwarming biofeedback to treat 37 migraineurs in a clinical outpatient setting. Methods 37 migraine patients underwent an average of 40 neurofeedback sessions combined with thermal biofeedback in an outpatient biofeedback clinic. All patients were on at least one type of medication for migraine; preventive, abortive or rescue. Patients kept daily headache diaries a minimum of two weeks prior to treatment and throughout treatment showing symptom frequency, severity, duration and medications used. Treatments were conducted an average of three times weekly over an average span of 6 months. Headache diaries were examined after treatment and a formal interview was conducted. After an average of 14.5 months following treatment, a formal interview was conducted in order to ascertain duration of treatment effects. Results Of the 37 migraine patients treated, 26 patients or 70% experienced at least a 50% reduction in the frequency of their headaches which was sustained on average 14.5 months after treatments were discontinued. Conclusions All combined neuro and biofeedback interventions were effective in reducing the frequency of migraines with clients using medication resulting in a more favorable outcome (70% experiencing at least a 50% reduction in headaches) than just medications alone (50% experience a 50% reduction) and that the effect size of our study involving three different types of biofeedback for migraine (1.09) was more robust than effect size of combined studies on thermal biofeedback alone for migraine (.5). These non-invasive interventions may show promise for treating treatment-refractory migraine and for preventing the progression from episodic to chronic migraine. PMID:20205867

  6. Thermal behaviour of the ESR Relaxation time in slightly dirty superconductors

    International Nuclear Information System (INIS)

    Schwachheim, G.; Machado, S.F.; Tsallis, C.

    1978-07-01

    The thermal behaviour of the ESR relaxation rate in slightly dirty superconductors is discussed for both exchange and spin-orbit interactions between the conduction electrons and the impurities. The sensibility to the electronic density of states is exhibited by using, in a modified BCS framework, an heuristic analytic form which avoids two of three defects of a previous similar treatment. The sudden increase (decrease) of the relaxation rate immediately below the critical temperature for the exchange (spin-orbit) case is confirmed. Reasonable agreement with experimental data in LaRu 2 ; Gd is obtained [pt

  7. Mechanical spectroscopy of thermal stress relaxation in aluminium alloys reinforced with short alumina fibres

    Energy Technology Data Exchange (ETDEWEB)

    Carreno-Morelli, E.; Schaller, R. [Ecole Polytechnique Federale, Lausanne (Switzerland). Inst. de Genie Atomique; Urreta, S.E.

    1998-05-01

    The mechanical behaviour under low temperature thermal cycling of aluminium-based composites reinforced with short Al{sub 2}O{sub 3} SAFFIL fibres has been investigated by mechanical spectroscopy (mechanical loss and elastic shear modulus measurements). A mechanical loss maximum has been observed during cooling which originates in the relaxation of thermal stresses at the interfaces due to the differential thermal expansion between matrix and reinforcement. The maximum height increases with the volumetric fibre content. In addition, if the matrix strength is increased by the appropriated choice of alloy and thermal treatment, the maximum diminishes and shifts to lower temperatures. No damage accumulation at the interfaces has been detected during long period thermal cycling in the range 100 to 500 K. A description of the damping behaviour is made in terms of the development of microplastic zones which surround the fibres. (orig.) 9 refs.

  8. Dielectric relaxation of 2-ethyl-1-hexanol around the glass transition by thermally stimulated depolarization currents.

    Science.gov (United States)

    Arrese-Igor, S; Alegría, A; Colmenero, J

    2015-06-07

    We explore new routes for characterizing the Debye-like and α relaxation in 2-ethyl-1-hexanol (2E1H) monoalcohol by using low frequency dielectric techniques including thermally stimulated depolarization current (TSDC) techniques and isothermal depolarization current methods. In this way, we have improved the resolution of the overlapped processes making it possible the analysis of the data in terms of a mode composition as expected for a chain-like response. Furthermore the explored ultralow frequencies enabled to study dynamics at relatively low temperatures close to the glass transition (Tg). Results show, on the one hand, that Debye-like and α relaxation timescales dramatically approach to each other upon decreasing temperature to Tg. On the other hand, the analysis of partial polarization TSDC data confirms the single exponential character of the Debye-like relaxation in 2E1H and rules out the presence of Rouse type modes in the scenario of a chain-like response. Finally, on crossing the glass transition, the Debye-like relaxation shows non-equilibrium effects which are further emphasized by aging treatment and would presumably emerge as a result of the arrest of the structural relaxation below Tg.

  9. Thermal relaxation of magnetic clusters in amorphous Hf57Fe43 alloy

    International Nuclear Information System (INIS)

    Pajic, Damir; Zadro, Kreso; Ristic, Ramir; Zivkovic, Ivica; Skoko, Zeljko; Babic, Emil

    2007-01-01

    The magnetization processes in binary magnetic/non-magnetic amorphous alloy Hf 57 Fe 43 are investigated by the detailed measurement of magnetic hysteresis loops, temperature dependence of magnetization, relaxation of magnetization and magnetic ac susceptibility, including a nonlinear term. Blocking of magnetic moments at lower temperatures is accompanied by the slow relaxation of magnetization and magnetic hysteresis loops. All of the observed properties are explained by the superparamagnetic behaviour of the single domain magnetic clusters inside the non-magnetic host, their blocking by the anisotropy barriers and thermal fluctuation over the barriers accompanied by relaxation of magnetization. From magnetic viscosity analysis based on thermal relaxation over the anisotropy barriers it is found that magnetic clusters occupy the characteristic volume from 25 up to 200 nm 3 . The validity of the superparamagnetic model of Hf 57 Fe 43 is based on the concentration of iron in the Hf 100-x Fe x system that is just below the threshold for long range magnetic ordering. This work also throws more light on the magnetic behaviour of other amorphous alloys

  10. Transient thermal and nonthermal electron and phonon relaxation after short-pulsed laser heating of metals

    International Nuclear Information System (INIS)

    Giri, Ashutosh; Hopkins, Patrick E.

    2015-01-01

    Several dynamic thermal and nonthermal scattering processes affect ultrafast heat transfer in metals after short-pulsed laser heating. Even with decades of measurements of electron-phonon relaxation, the role of thermal vs. nonthermal electron and phonon scattering on overall electron energy transfer to the phonons remains unclear. In this work, we derive an analytical expression for the electron-phonon coupling factor in a metal that includes contributions from equilibrium and nonequilibrium distributions of electrons. While the contribution from the nonthermal electrons to electron-phonon coupling is non-negligible, the increase in the electron relaxation rates with increasing laser fluence measured by thermoreflectance techniques cannot be accounted for by only considering electron-phonon relaxations. We conclude that electron-electron scattering along with electron-phonon scattering have to be considered simultaneously to correctly predict the transient nature of electron relaxation during and after short-pulsed heating of metals at elevated electron temperatures. Furthermore, for high electron temperature perturbations achieved at high absorbed laser fluences, we show good agreement between our model, which accounts for d-band excitations, and previous experimental data. Our model can be extended to other free electron metals with the knowledge of the density of states of electrons in the metals and considering electronic excitations from non-Fermi surface states

  11. Influence of relaxation processes on the structure of a thermal boundary layer in partially ionized argon

    International Nuclear Information System (INIS)

    Dongen, M.E.H. van; Eck, R.B. van P. van; Hagebeuk, H.J.L.; Hirschberg, A.; Hutten-Mansfeld, A.C.B.; Jager, H.J.; Willems, J.F.H.

    1981-01-01

    A model for the unsteady thermal boundary-layer development at the end wall of a shock tube, in partially ionized atmospheric argon, is proposed. Consideration is given to ionization and thermal relaxation processes. In order to obtain some insight into the influence of the relaxation processes on the structure of the boundary layer, a study of the frozen and equilibrium limits has been carried out. The transition from a near-equilibrium situation in the outer part of the boundary layer towards a frozen situation near the wall is determined numerically. Experimental data on the electron and atom density profiles obtained from laser schlieren and absorption measurements are presented. A quantitative agreement between theory and experiment is found for a moderate degree of ionization (3%). At a higher degree of ionization the structure of the boundary layer is dominated by the influence of radiation cooling, which has been neglected in the model. (author)

  12. Advanced biofeedback from surface electromyography signals using fuzzy system

    DEFF Research Database (Denmark)

    Samani, Afshin; Holtermann, Andreas; Søgaard, Karen

    2010-01-01

    The aims of this study were to develop a fuzzy inference-based biofeedback system and investigate its effects when inducing active (shoulder elevation) and passive (relax) pauses on the trapezius muscle electromyographic (EMG) activity during computer work. Surface EMG signals were recorded from...

  13. Crystallization, structural relaxation and thermal degradation in Poly(L-lactide)/cellulose nanocrystal renewable nanocomposites.

    Science.gov (United States)

    Lizundia, E; Vilas, J L; León, L M

    2015-06-05

    In this work, crystallization, structural relaxation and thermal degradation kinetics of neat Poly(L-lactide) (PLLA) and its nanocomposites with cellulose nanocrystals (CNC) and CNC-grafted-PLLA (CNC-g-PLLA) have been studied. Although crystallinity degree of nanocomposites remains similar to that of neat homopolymer, results reveal an increase on the crystallization rate by 1.7-5 times boosted by CNC, which act as nucleating agents during the crystallization process. In addition, structural relaxation kinetics of PLLA chains has been drastically reduced by 53% and 27% with the addition of neat and grafted CNC, respectively. The thermal degradation activation energy (E) has been determined from thermogravimetric analysis in the light of Kissinger's and Ozawa-Flynn-Wall theoretical models. Results reveal a reduction on the thermal stability when in presence of CNC-g-PLLA, while raw CNC slightly increases the thermal stability of PLLA. Fourier transform infrared spectroscopy and energy dispersive X-ray spectroscopy results confirm that the presence of residual catalyst in CNC-g-PLLA plays a pivotal role in the thermal degradation behavior of nanocomposites. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. Crater relaxation on Titan aided by low thermal conductivity sand infill

    Science.gov (United States)

    Schurmeier, Lauren R.; Dombard, Andrew J.

    2018-05-01

    Titan's few impact craters are currently many hundreds of meters shallower than the depths expected. Assuming these craters initially had depths equal to that of similar-size fresh craters on Ganymede and Callisto (moons of similar size, composition, and target lithology), then some process has shallowed them over time. Since nearly all of Titan's recognized craters are located within the arid equatorial sand seas of organic-rich dunes, where rain is infrequent, and atmospheric sedimentation is expected to be low, it has been suggested that aeolian infill plays a major role in shallowing the craters. Topographic relaxation at Titan's current heat flow was previously assumed to be an unimportant process on Titan due to its low surface temperature (94 K). However, our estimate of the thermal conductivity of Titan's organic-rich sand is remarkably low (0.025 W m-1 K-1), and when in thick deposits, will result in a thermal blanketing effect that can aid relaxation. Here, we simulate the relaxation of Titan's craters Afekan, Soi, and Sinlap including thermal effects of various amounts of sand inside and around Titan's craters. We find that the combination of aeolian infill and subsequent relaxation can produce the current crater depths in a geologically reasonable period of time using Titan's current heat flow. Instead of needing to fill completely the missing volume with 100% sand, only ∼62%, ∼71%, and ∼97%, of the volume need be sand at the current basal heat flux for Afekan, Soi, and Sinlap, respectively. We conclude that both processes are likely at work shallowing these craters, and this finding contributes to why Titan overall lacks impact craters in the arid equatorial regions.

  15. Thermal effect of Zn quantum dots grown on Si(111): competition between relaxation and reconstraint

    Science.gov (United States)

    Kao, Li-Chi; Huang, Bo-Jia; Zheng, Yu-En; Tu, Kai-Teng; Chiu, Shang-Jui; Ku, Ching-Shun; Lo, Kuang Yao

    2018-01-01

    Zn dots are potential solutions for metal contacts in future nanodevices. The metastable states that exist at the interface between Zn quantum dots and oxide-free Si(111) surfaces can suppress the development of the complete relaxation and increase the size of Zn dots. In this work, the actual heat consumption of the structural evolution of Zn dots resulting from extrinsic thermal effect was analyzed. Zn dots were coherently grown on oxide-free Si(111) through magnetron RF sputtering. A compensative optical method combined with reflective second harmonic generation and synchrotron x-ray diffraction (XRD) was developed to statistically analyze the thermal effect on the Zn dot system. Pattern matching (3 m) between the Zn and oxide-free Si(111) surface enabled Si(111) to constrain Zn dots from a liquid to solid phase. Annealing under vacuum induced smaller, loose Zn dots to be reconstrained by Si(111). When the size of the Zn dots was in the margin of complete relaxation, the Zn dot was partially constrained by potential barriers (metastable states) between Zn(111) and one of the six in-planes of Si〈110〉. The thermal disturbance exerted by annealing would enable partially constrained ZnO/Zn dots to overcome the potential barrier and be completely relaxed, which is obvious on the transition between Zn(111) and Zn(002) peak in synchrotron XRD. Considering the actual irradiated surface area of dots array in a wide-size distribution, the competition between reconstrained and relaxed Zn dots on Si(111) during annealing was statistically analyzed.

  16. Biofeedback-driven dialysis: where are we?

    Science.gov (United States)

    Santoro, Antonio; Ferramosca, Emiliana; Mancini, Elena

    2008-01-01

    interactions between the actuators and the controlled variable. In these cases, more sophisticated control systems are needed, which must be capable of identifying the behavior of the process, and continuously update information data while the control is on. These complex systems are called adaptive controllers. In dialysis, over the last few years, it has been relatively easy to realize some biofeedback systems since a series of sensors have been developed for online monitoring. Three biofeedback devices are routinely used with the aim of improving the cardiovascular instability, one of the main problems limiting the tolerance to treatment by the patient and the quality of HD in itself - the first is the biofeedback control of blood volume, the second is the biofeedback control of thermal balance, and the third is the biofeedback control of blood pressure.

  17. Typical Relaxation of Isolated Many-Body Systems Which Do Not Thermalize

    Science.gov (United States)

    Balz, Ben N.; Reimann, Peter

    2017-05-01

    We consider isolated many-body quantum systems which do not thermalize; i.e., expectation values approach an (approximately) steady longtime limit which disagrees with the microcanonical prediction of equilibrium statistical mechanics. A general analytical theory is worked out for the typical temporal relaxation behavior in such cases. The main prerequisites are initial conditions which appreciably populate many energy levels and do not give rise to significant spatial inhomogeneities on macroscopic scales. The theory explains very well the experimental and numerical findings in a trapped-ion quantum simulator exhibiting many-body localization, in ultracold atomic gases, and in integrable hard-core boson and X X Z models.

  18. Stress induced conditioning and thermal relaxation in the simulation of quasi-static compression experiments

    International Nuclear Information System (INIS)

    Scalerandi, M; Delsanto, P P; Johnson, P A

    2003-01-01

    Local interaction simulation approach simulations of the ultrasonic wave propagation in multi-grained materials have succeeded in reproducing most of the recently observed nonclassical nonlinear effects, such as stress-strain hysteresis and discrete memory in quasi-static experiments and a downwards shift of the resonance frequency and the generation of odd harmonics at specific amplitude rates in dynamics experiments. By including a simple mechanism of thermally activated random transitions, we can predict the occurrence of experimentally observed effects, such as the conditioning and relaxation of the specimen. Experiments are also suggested for a quantitative assessment of the validity of the model

  19. Stress induced conditioning and thermal relaxation in the simulation of quasi-static compression experiments

    CERN Document Server

    Scalerandi, M; Johnson, P A

    2003-01-01

    Local interaction simulation approach simulations of the ultrasonic wave propagation in multi-grained materials have succeeded in reproducing most of the recently observed nonclassical nonlinear effects, such as stress-strain hysteresis and discrete memory in quasi-static experiments and a downwards shift of the resonance frequency and the generation of odd harmonics at specific amplitude rates in dynamics experiments. By including a simple mechanism of thermally activated random transitions, we can predict the occurrence of experimentally observed effects, such as the conditioning and relaxation of the specimen. Experiments are also suggested for a quantitative assessment of the validity of the model.

  20. Isothermal relaxation current and microstructure changes of thermally aged polyester films impregnated by epoxy resin

    Science.gov (United States)

    Jiang, Xiongwei; Sun, Potao; Peng, Qingjun; Sima, Wenxia

    2018-01-01

    In this study, to understand the effect of thermal aging on polymer films degradation, specimens of polyester films impregnated by epoxy resin with different thermal aging temperatures (80 and 130 °C) and aging times (500, 1600, 2400 and 3000 h) are prepared, then charge de-trapping properties of specimens are investigated via the isothermal relaxation current (IRC) measurement, the distributions of trap level and its corresponding density are obtained based on the modified IRC model. It is found that the deep trap density increases remarkably at the beginning of thermal aging (before 1600 h), but it decreases obviously as the aging degree increases. At elevated aging temperature and, in particular considering the presence of air gap between two-layer insulation, the peak densities of deep traps decrease more significant in the late period of aging. It can be concluded that it is the released energy from de-trapping process leads to the fast degradation of insulation. Moreover, after thermal aging, the microstructure changes of crystallinity and molecular structures are analyzed via the x-ray diffraction experiment and Fourier transform infrared spectrometer. The results indicate that the variation of the deep trap density is closely linked with the changes of microstructure, a larger interface of crystalline/amorphous phase, more defects and broken chains caused by thermal aging form higher deep trap density stored in the samples.

  1. A coupled magneto-thermo-elastic problem in a perfectly conducting elastic half-space with thermal relaxation

    Directory of Open Access Journals (Sweden)

    S. K. Roy-Choudhuri

    1990-01-01

    Full Text Available In the present paper we consider the magneto-thermo-elastic wave produced by a thermal shock in a perfectly conducting elastic half-space. Here the Lord-Shulman theory of thermoelasticity [1] is used to account for the interaction between the elastic and thermal fields. The solution obtained in analytical form reduces to those of Kaliski and Nowacki [2] when the coupling between the temperature and strain fields and the relaxation time are neglected. The results also agree with those of Massalas and DaLamangas [3] in absence of the thermal relaxation time.

  2. [Biofeedback treatment for acute whiplash patients].

    Science.gov (United States)

    Gálvez-Hernández, Carmen Lizette; Rodríguez-Ortiz, María Dolores; Del Río-Portilla, Yolanda

    2016-01-01

    The aim of this study is to evaluate the physiological and psychological effect after an electromyographic biofeedback treatment in combination with progressive muscular relaxation training in patients with acute whiplash. Twelve patients with acute whiplash volunteered to participate in a quasi-experimental design and a control group. Two months maximum after car accident, severity levels II and I. previous history of persistent pain or serious previous injury. The groups were randomly divided in two (treatment and waiting list groups). We used electromyographic measures of the trapezius muscles with psychometric tests: Beck Anxiety and Depression Inventory; Oswestry Pain Disability Questionnaire; Visual Analog Scale of Pain; TAMPA Scale for Kinesiophobia. The treatment consisted in electromyographic biofeedback after progressive muscular relaxation training. There were significant intra-group differences before and after treatment in muscular symmetry and subjective pain perception in the treatment group. We achieved a significant change (clinical and statistical) in subjective pain perception and muscular symmetry. This study highlights the importance of multidisciplinary work in acute pain patients and the effectiveness of clinical psychophysiological strategies with acute whiplash patients.

  3. Biofeedback. Psychofysiologische en leertheoretische aspecten

    NARCIS (Netherlands)

    Bakker, Schelte Jan

    1978-01-01

    Het voornaamste uitgangspunt van deze studie was de gecompliceerdheid van biofeedback, waarin diverse psychologische en psychofysiologische processen een rol spelen. Het belang van theorie-ontwikkeling- ook ten behoeve van toepassingen van de biofeedback- werd uiteengezet en de nadruk lag dan ook op

  4. Biofeedback: The Beat Goes On

    Science.gov (United States)

    Kater, Donna; Spires, Jeanette

    1975-01-01

    This article reviews some of the research applications of biofeedback techniques and suggests how these may be of use in counseling. The goals toward which biofeedback can be used are increased self-awareness, integration of the individual, and the freedom to make choices regarding states of consciousness. (SJL)

  5. Biofeedback training in chronic constipation

    NARCIS (Netherlands)

    Benninga, M. A.; Büller, H. A.; Taminiau, J. A.

    1993-01-01

    Twenty nine patients, aged 5-16 years, were studied to evaluate whether biofeedback training is effective in treating children with chronic constipation and encopresis; the clinical outcome at six weeks and 12 months was also evaluated. Patients received on average five biofeedback training

  6. Thermal relaxation and heat transport in spin ice Dy{sub 2}Ti{sub 2}O{sub 7}

    Energy Technology Data Exchange (ETDEWEB)

    Klemke, Bastian; Meissner, M.; Tennant, D.A. [Helmholtz-Zentrum Berlin (Germany); Technische Universitaet Berlin (Germany); Strehlow, P. [Technische Universitaet Berlin (Germany); Physikalisch Technische Bundesanstalt, Institut Berlin (Germany); Kiefer, K. [Helmholtz-Zentrum Berlin (Germany); Grigera, S.A. [School of Physics and Astronomy, St. Andrews (United Kingdom); Instituto de Fisica de Liquidos y Sistemas Biologicos, CONICET, UNLP, La Plata (Argentina)

    2011-07-01

    The thermal properties of single crystalline Dy{sub 2}Ti{sub 2}O{sub 7} have been studied at temperature below 30 K and magnetic fields applied along [110] direction up to 1.5 T. Based on a thermodynamic field theory (TFT) various heat relaxation and thermal transport measurements were analysed. So we were able to present not only the heat capacity of Dy{sub 2}Ti{sub 2}O{sub 7}, but also for the first time the different contributions of the magnetic excitations and their corresponding relaxation times in the spin ice phase. In addition, the thermal conductivity and the shortest relaxation time were determined by thermodynamic analysis of steady state heat transport measurements. Finally, we were able to reproduce the temperature profiles recorded in heat pulse experiments on the basis of TFT using the previously determined heat capacity and thermal conductivity data without additional parameters. Thus, TFT has been proved to be thermodynamically consistent in describing three thermal transport experiments on different time scales. The observed temperature and field dependencies of heat capacity contributions and relaxation times indicate the magnetic excitations in the spin ice Dy{sub 2}Ti{sub 2}O{sub 7} as thermally activated monopole-antimonopole defects.

  7. Comparative performance of the conjugate gradient and SOR [Successive Over Relaxation] methods for computational thermal hydraulics

    International Nuclear Information System (INIS)

    King, J.B.; Anghaie, S.; Domanus, H.M.

    1987-01-01

    Finite difference approximations to the continuity, momentum, and energy equations in thermal hydraulics codes result in a system of N by N equations for a problem having N field points. In a three dimensional problem, N increases as the problem becomes larger or more complex, and more rapidly as the computational mesh size is reduced. As a consequence, the execution time required to solve the problem increases, which may lead to placing limits on the problem resolution or accuracy. A conventinal method of solution of these systems of equations is the Successive Over Relaxation (SOR) technique. However, for a wide range of problems the execution time may be reduced by using a more efficient linear equation solver. One such method is the conjugate gradient method which was implemented in COMMIX-1B thermal hydraulics code. It was found that the execution time required to solve the resulting system of equations was reduced by a factor of about 2 for some problems. This paper summarizes the characteristics of these iterative solution procedures and compares their performance in modeling of a variety of reactor thermal hydraulic problems, using the COMMIX-1B computer code

  8. Lyapunov stability and thermal stability of partially relaxed fluids and plasmas

    International Nuclear Information System (INIS)

    Elsaesser, K.; Spiess, P.

    1996-01-01

    The relation between the Lyapunov stability of a Hamiltonian system and the thermal stability of a fluid whose temperature is controlled from outside is explored: The free energy as a functional of the correct variables (specific volume, local entropy, and some Clebsch potentials of the velocity) may serve as a Lyapunov functional, depending on the open-quote open-quote Casimirs close-quote close-quote as exchanged quantities. For a multi-species plasma one obtains a sufficient condition for stability: γ(v 2 /c 2 s )-1 s the sound speed. Some features of partially relaxed (T=const) cylindrical plasmas are also discussed. copyright 1996 American Institute of Physics

  9. Recent developments in biofeedback for neuromotor rehabilitation

    Directory of Open Access Journals (Sweden)

    He Jiping

    2006-06-01

    Full Text Available Abstract The original use of biofeedback to train single muscle activity in static positions or movement unrelated to function did not correlate well to motor function improvements in patients with central nervous system injuries. The concept of task-oriented repetitive training suggests that biofeedback therapy should be delivered during functionally related dynamic movement to optimize motor function improvement. Current, advanced technologies facilitate the design of novel biofeedback systems that possess diverse parameters, advanced cue display, and sophisticated control systems for use in task-oriented biofeedback. In light of these advancements, this article: (1 reviews early biofeedback studies and their conclusions; (2 presents recent developments in biofeedback technologies and their applications to task-oriented biofeedback interventions; and (3 discusses considerations regarding the therapeutic system design and the clinical application of task-oriented biofeedback therapy. This review should provide a framework to further broaden the application of task-oriented biofeedback therapy in neuromotor rehabilitation.

  10. I. Construction of an ultralow temperature laboratory. II. Thermal relaxation in superfluid helium-3

    International Nuclear Information System (INIS)

    Neuhauser, B.J.

    1986-01-01

    The first part of this thesis describes the construction of an ultralow temperature laboratory capable of reaching temperatures below 0.002 K. Continuous refrigeration to 0.012 K is provided by a cold plate/dilution refrigerator system. Single-cycle cooling to 0.002 K is accomplished by adiabatic demagnetization of cerous magnesium nitrate (CMN), a paramagnetic salt. Thermometry is done by measuring the resistance of carbon and germanium sensors, the magnetic susceptibility of lanthanum-diluted CMN, and the anisotropy of gamma radiation from a cobalt-60 nuclear orientation thermometer. Systems have been developed to allow precise control of the temperature and pressure of the liquid helium-3 sample. Measurements of thermal relaxation of liquid helium-3 in the ultralow temperature cell following sudden magnetic cooling of the CMN refrigerant are described. Analysis of the transient response of a thermal model of the cell indicates that the ratio of the time constants immediately below and above the superfluid-to-normal transition temperature provides a close estimate of the ratio of the corresponding helium-3 heat capacities, at least in the superfluid A-phase

  11. Thermally Driven Transport and Relaxation Switching Self-Powered Electromagnetic Energy Conversion.

    Science.gov (United States)

    Cao, Maosheng; Wang, Xixi; Cao, Wenqiang; Fang, Xiaoyong; Wen, Bo; Yuan, Jie

    2018-06-07

    Electromagnetic energy radiation is becoming a "health-killer" of living bodies, especially around industrial transformer substation and electricity pylon. Harvesting, converting, and storing waste energy for recycling are considered the ideal ways to control electromagnetic radiation. However, heat-generation and temperature-rising with performance degradation remain big problems. Herein, graphene-silica xerogel is dissected hierarchically from functions to "genes," thermally driven relaxation and charge transport, experimentally and theoretically, demonstrating a competitive synergy on energy conversion. A generic approach of "material genes sequencing" is proposed, tactfully transforming the negative effects of heat energy to superiority for switching self-powered and self-circulated electromagnetic devices, beneficial for waste energy harvesting, conversion, and storage. Graphene networks with "well-sequencing genes" (w = P c /P p > 0.2) can serve as nanogenerators, thermally promoting electromagnetic wave absorption by 250%, with broadened bandwidth covering the whole investigated frequency. This finding of nonionic energy conversion opens up an unexpected horizon for converting, storing, and reusing waste electromagnetic energy, providing the most promising way for governing electromagnetic pollution with self-powered and self-circulated electromagnetic devices. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. Effects of biofeedback on obstructive defecation--reconditioning of the defecation reflex?

    Science.gov (United States)

    Papachrysostomou, M; Smith, A N

    1994-01-01

    Twenty two patients with obstructive defecation were recruited for relaxation training by domiciliary self regulatory biofeedback. Each patient served as his or her own control for anorectal and proctographic assessments. Biofeedback training improved the obstructive symptoms of the patients and showed significant change in various parameters related to the obstructive defecation syndrome. As examined by isotope dynamic proctography: the defecation rate (% of evacuation/defecation time) was significantly increased (p anismus index (p < 0.0001). The rectal sensation was improved (p < 0.05), concomitantly. Biofeedback thus improves the defecation act in patients suffering from inappropriate contraction of the pelvic floor and sphincter musculature. Furthermore, this study has shown that biofeedback objectively influences the defecation reflex leading to an improved quality of higher control of bowel function. PMID:8307478

  13. Biofeedback for psychiatric disorders: a systematic review

    NARCIS (Netherlands)

    Schoenberg, P.L.; David, A.S.

    2014-01-01

    Biofeedback potentially provides non-invasive, effective psychophysiological interventions for psychiatric disorders. The encompassing purpose of this review was to establish how biofeedback interventions have been used to treat select psychiatric disorders [anxiety, autistic spectrum disorders,

  14. Feasibility and acceptance of biofeedback-assisted mental training in an Austrian elementary school: a pilot study.

    Science.gov (United States)

    Crevenna, Richard; Krammer, Christine; Keilani, Mohammad

    2016-04-01

    This pilot study aimed to investigate feasibility, acceptance, and effects of biofeedback-assisted mental training in a population of fifteen 10-year-old pupils in an Austrian elementary school. Participants were instructed in relaxation techniques by using biofeedback. Before intervention, after 6 weeks with active mental training and with regular instructions by the teacher, and after a further time period of 6 weeks without instructions, attention and concentration improved. The results indicate feasibility, good acceptance, and beneficial effects of biofeedback-assisted mental techniques in Austrian elementary school pupils.

  15. An anisotropic linear thermo-viscoelastic constitutive law - Elastic relaxation and thermal expansion creep in the time domain

    Science.gov (United States)

    Pettermann, Heinz E.; DeSimone, Antonio

    2017-09-01

    A constitutive material law for linear thermo-viscoelasticity in the time domain is presented. The time-dependent relaxation formulation is given for full anisotropy, i.e., both the elastic and the viscous properties are anisotropic. Thereby, each element of the relaxation tensor is described by its own and independent Prony series expansion. Exceeding common viscoelasticity, time-dependent thermal expansion relaxation/creep is treated as inherent material behavior. The pertinent equations are derived and an incremental, implicit time integration scheme is presented. The developments are implemented into an implicit FEM software for orthotropic material symmetry under plane stress assumption. Even if this is a reduced problem, all essential features are present and allow for the entire verification and validation of the approach. Various simulations on isotropic and orthotropic problems are carried out to demonstrate the material behavior under investigation.

  16. Effects of thermal relaxation on an amorphous superconducting Zr--Rh alloy

    International Nuclear Information System (INIS)

    Drehman, A.J.; Johnson, W.L.

    1978-05-01

    The electronic and superconducting properties of an amorphous transition metal alloy are used to evaluate the effects of low temperature annealing. It is observed that the superconducting transition temperature and the electrical resistivity relax exponentially in time from their initial value to a final relaxed value. From this an activation energy for the relaxation process is derived and an explanation is suggested which involves internal stress

  17. 21 CFR 882.5050 - Biofeedback device.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Biofeedback device. 882.5050 Section 882.5050 Food... DEVICES NEUROLOGICAL DEVICES Neurological Therapeutic Devices § 882.5050 Biofeedback device. (a) Identification. A biofeedback device is an instrument that provides a visual or auditory signal corresponding to...

  18. Multiple relaxation processes in high-energy ion irradiated kapton-H polyimide: Thermally stimulated depolarization current study

    International Nuclear Information System (INIS)

    Garg, Maneesha; Quamara, J.K.

    2006-01-01

    High-energy ion irradiation effects on the thermally stimulated depolarization current (Tdc) behaviour of kapton-H samples (12.5 μm) irradiated with 50 MeV Li ion (fluence 5 x 10 4 , 10 5 and 5 x 10 5 ions/cm 2 ) have been investigated. The TSDC spectra of the irradiated samples reveal that the β-peak (appearing around 80-110 deg. C) associated with dipolar relaxation has been significantly affected owing to the demerization of carbonyl groups due to irradiation. The TSDC spectra also reveal a new relaxation process (termed as γ-relaxation) around 30 deg. C, due to increased water absorptivity in irradiated samples. The peak around 200 deg. C (α-peak) associated with space charge relaxation process also shows a behavioural change with ion irradiation. The peak not only shifts towards the higher temperature with increasing fluence but also show an increase in its activation energy (0.33-0.99 eV) with increasing polarizing field. The creation of new deep energy trap centers due to the formation of conjugated bonds after irradiation is responsible for this modification. The Cole-Cole distribution curves show the formation of new sub-polar group with different characteristic relaxation time

  19. X-ray diffraction study of thermal stress relaxation in ZnO films deposited by magnetron sputtering

    Energy Technology Data Exchange (ETDEWEB)

    Conchon, F. [Institut P' , Universite de Poitiers-Ensma-UPR CNRS 3346, 86962 Futuroscope (France); Renault, P.O., E-mail: pierre.olivier.renault@univ-poitiers.f [Institut P' , Universite de Poitiers-Ensma-UPR CNRS 3346, 86962 Futuroscope (France); Le Bourhis, E.; Krauss, C.; Goudeau, P. [Institut P' , Universite de Poitiers-Ensma-UPR CNRS 3346, 86962 Futuroscope (France); Barthel, E.; Grachev, S. Yu.; Sondergard, E. [Lab. Surface du Verre et Interfaces (SVI), UMR 125, 93303 Aubervilliers (France); Rondeau, V.; Gy, R. [Lab. Recherche de Saint-Gobain (SGR), 93303 Aubervilliers (France); Lazzari, R.; Jupille, J. [Institut des Nanosciences de Paris (INSP), UMR 7588, 75015 Paris (France); Brun, N. [Lab. Physique des Solides (LPS), UMR 8502, 91405 Orsay (France)

    2010-12-30

    X-ray diffraction stress analyses have been performed on two different thin films deposited onto silicon substrate: ZnO and ZnO encapsulated into Si{sub 3}N{sub 4} layers. We showed that both as-deposited ZnO films are in a high compressive stress state. In situ X-ray diffraction measurements inside a furnace revealed a relaxation of the as-grown stresses at temperatures which vary with the atmosphere in the furnace and change with Si{sub 3}N{sub 4} encapsulation. The observations show that Si{sub 3}N{sub 4} films lying on both sides of the ZnO film play an important role in the mechanisms responsible for the stress relaxation during heat treatment. The different temperatures observed for relaxation in ambient and argon atmospheres suggest that the thermally activated stress relaxation may be attributed to a variation of the stoichiometry of the ZnO films. The present observations pave the way to fine tuning of the residual stresses through thermal treatment parameters.

  20. Thermal Annealing induced relaxation of compressive strain in porous GaN structures

    KAUST Repository

    Ben Slimane, Ahmed; Najar, Adel; Ng, Tien Khee; Ooi, Boon S.

    2012-01-01

    The effect of annealing on strain relaxation in porous GaN fabricated using electroless chemical etching is presented. The Raman shift of 1 cm-1 in phonon frequency of annealed porous GaN with respect to as-grown GaN corresponds to a relaxation

  1. Autogenic Training and Hand Temperature Biofeedback in the Treatment of Migraine: A Preliminary Analysis.

    Science.gov (United States)

    Jessup, B.; And Others

    The possibility of alleviating migraine headaches by autogenic relaxation training, with or without hand temperature biofeedback, was assessed. The study examined five independent groups in a bi-directional control group design. Volunteer migraine sufferers served as subjects, each participating for 12 weeks. The first four weeks of the study were…

  2. Anismus and biofeedback: who benefits?

    Science.gov (United States)

    Siproudhis, L; Dautrème, S; Ropert, A; Briand, H; Renet, C; Beusnel, C; Juguet, F; Rabot, A F; Bretagne, J F; Gosselin, M

    1995-06-01

    Biofeedback is the main treatment for dyschezia in patients with anismus, but retraining may fail because of the frequent association of pelvirectal disorders with anismus. We set out to identify indices of biofeedback failure in the treatment of anismus. From May 1990 to May 1993, 27 patients (20 women and seven men; median age 46 years) with anismus in which dyschezia was not improved by laxative agents were enrolled in a biofeedback retraining programme. All patients underwent proctologic examination, anal manometry and defecography. Anismus was defined as an increase in anal pressure during attempted defecation in conjunction with an impairment of rectal emptying as assessed using an objective test (barium paste expulsion). Associated disorders were encountered frequently. These included abnormal perineal descent (22 cases), large rectocoele (12 cases), high-grade rectal prolapse (six cases), abnormally high anal canal pressures at rest (seven cases) and abnormal rectal response to inflation (20 cases). Anismus was the sole abnormality in 12 patients when perineal descent, low-grade prolapse and abnormal rectal sensations were not taken into account. Biofeedback retraining did not suppress dyschezia in 13 out of 27 patients. Neither associated disorders (rectocoele, rectal prolapse, abnormal perineal descent, anal pressure and abnormalities of rectal sensation) nor a relevant past history (hysterectomy, laxative abuse, use of antidepressive agents) were encountered more frequently in these 13 patients than in the other 14. The duration of symptoms before treatment was significantly longer in the group unresponsive to biofeedback retraining (81 +/- 61 compared with 33 +/- 34 months for the responsive group, P anismus is not mandatory because the failure of retraining (48%) is not related to the presence of associated pelvirectal disorders. (2) A long past history of dyschezia seems to provide an index of the failure of biofeedback retraining.

  3. Pressure dependence of thermal conductivity and specific heat in CeRh2Si2 measured by an extended thermal relaxation method

    Science.gov (United States)

    Nishigori, Shijo; Seida, Osamu

    2018-05-01

    We have developed a new technique for measuring thermal conductivity and specific heat under pressure by improving a thermal relaxation method. In this technique, a cylindrical sample with a small disc heater is embedded in the pressure-transmitting medium, then temperature variations of the sample and heater were directly measured by thermocouples during a heating and cooling process. Thermal conductivity and specific heat are estimated by comparing the experimental data with temperature variations simulated by a finite element method. The obtained thermal conductivity and specific heat of the test sample CeRh2Si2 exhibit a small enhancement and a clear peak arising from antiferromagnetic transition, respectively. The observation of these typical behaviors for magnetic compounds indicate that the technique is valid for the study on thermal properties under pressure.

  4. Biofeedback for robotic gait rehabilitation

    Directory of Open Access Journals (Sweden)

    Colombo Gery

    2007-01-01

    Full Text Available Abstract Background Development and increasing acceptance of rehabilitation robots as well as advances in technology allow new forms of therapy for patients with neurological disorders. Robot-assisted gait therapy can increase the training duration and the intensity for the patients while reducing the physical strain for the therapist. Optimal training effects during gait therapy generally depend on appropriate feedback about performance. Compared to manual treadmill therapy, there is a loss of physical interaction between therapist and patient with robotic gait retraining. Thus, it is difficult for the therapist to assess the necessary feedback and instructions. The aim of this study was to define a biofeedback system for a gait training robot and test its usability in subjects without neurological disorders. Methods To provide an overview of biofeedback and motivation methods applied in gait rehabilitation, previous publications and results from our own research are reviewed. A biofeedback method is presented showing how a rehabilitation robot can assess the patients' performance and deliver augmented feedback. For validation, three subjects without neurological disorders walked in a rehabilitation robot for treadmill training. Several training parameters, such as body weight support and treadmill speed, were varied to assess the robustness of the biofeedback calculation to confounding factors. Results The biofeedback values correlated well with the different activity levels of the subjects. Changes in body weight support and treadmill velocity had a minor effect on the biofeedback values. The synchronization of the robot and the treadmill affected the biofeedback values describing the stance phase. Conclusion Robot-aided assessment and feedback can extend and improve robot-aided training devices. The presented method estimates the patients' gait performance with the use of the robot's existing sensors, and displays the resulting biofeedback

  5. Bioelectrical activity of the pelvic floor muscles after 6-week biofeedback training in nulliparous continent women.

    Science.gov (United States)

    Chmielewska, Daria; Stania, Magdalena; Smykla, Agnieszka; Kwaśna, Krystyna; Błaszczak, Edward; Sobota, Grzegorz; Skrzypulec-Plinta, Violetta

    2016-01-01

    The aim of the study was to evaluate the effects of a 6-week sEMG-biofeedback-assisted pelvic floor muscle training program on pelvic floor muscle activity in young continent women. Pelvic floor muscle activity was recorded using a vaginal probe during five experimental trials. Biofeedback training was continued for 6 weeks, 3 times a week. Muscle strenghtening and endurance exercises were performed alternately. SEMG (surface electromyography) measurements were recorded on four different occasions: before training started, after the third week of training, after the sixth week of training, and one month after training ended. A 6-week sEMG-biofeedback-assisted pelvic floor muscle training program significantly decreased the resting activity of the pelvic floor muscles in supine lying and standing. The ability to relax the pelvic floor muscles after a sustained 60-second contraction improved significantly after the 6-week training in both positions. SEMG-biofeedback training program did not seem to affect the activity of the pelvic floor muscles or muscle fatigue during voluntary pelvic floor muscle contractions. SEMG-biofeedback-assisted pelvic floor muscle training might be recommended for physiotherapists to improve the effectiveness of their relaxation techniques.

  6. Thermal Annealing induced relaxation of compressive strain in porous GaN structures

    KAUST Repository

    Ben Slimane, Ahmed

    2012-01-01

    The effect of annealing on strain relaxation in porous GaN fabricated using electroless chemical etching is presented. The Raman shift of 1 cm-1 in phonon frequency of annealed porous GaN with respect to as-grown GaN corresponds to a relaxation of compressive strain by 0.41 ± 0.04 GPa. The strain relief promises a marked reduction in threading dislocation for subsequent epitaxial growth.

  7. Thermal relaxation time of a mixture of relativistic electrons and neutrinos

    International Nuclear Information System (INIS)

    Herrera, M.A.; Hacyan, S.

    1987-01-01

    The interaction between the components of a relativistic binary mixture is studied by means of a fully covariant formalism. Assuming both components to differ slightly in temperature, an application of the relativistic Boltzmann equation yields general expressions for the energy transfer rate and for the relaxation time of the system. The resulting relation is then applied to a mixture of relativistic electrons and neutrinos to obtain numerical values of its relaxation time. (author)

  8. Heart Rate Variability Biofeedback Does Not Substitute for Asthma Steroid Controller Medication.

    Science.gov (United States)

    Lehrer, Paul M; Irvin, Charles G; Lu, Shou-En; Scardella, Anthony; Roehmheld-Hamm, Beatrix; Aviles-Velez, Milisyaris; Graves, Jessica; Vaschillo, Evgeny G; Vaschillo, Bronya; Hoyte, Flavia; Nelson, Harold; Wamboldt, Frederick S

    2018-03-01

    Despite previous findings of therapeutic effects for heart rate variability biofeedback (HRVB) on asthma, it is not known whether HRVB can substitute either for controller or rescue medication, or whether it affects airway inflammation. Sixty-eight paid volunteer steroid naïve study participants with mild or moderate asthma were given 3 months of HRVB or a comparison condition consisting of EEG alpha biofeedback with relaxing music and relaxed paced breathing (EEG+), in a two-center trial. All participants received a month of intensive asthma education prior to randomization. Both treatment conditions produced similar significant improvements on the methacholine challenge test (MCT), asthma symptoms, and asthma quality of life (AQOL). MCT effects were of similar size to those of enhanced placebo procedures reported elsewhere, and were 65% of those of a course of a high-potency inhaled steroid budesonide given to a sub-group of participants following biofeedback training. Exhaled nitric oxide decreased significantly only in the HRVB group, 81% of the budesonide effect, but with no significant differences between groups. Participants reported becoming more relaxed during practice of both techniques. Administration of albuterol after biofeedback sessions produced a large improvement in pulmonary function test results, indicating that neither treatment normalized pulmonary function as a potent controller medication would have done. Impulse oscillometry showed increased upper airway (vocal cord) resistance during biofeedback periods in both groups. These data suggest that HRVB should not be considered an alternative to asthma controller medications (e.g., inhaled steroids), although both biofeedback conditions produced some beneficial effects, warranting further research, and suggesting potential complementary effects. Various hypotheses are presented to explain why HRVB effects on asthma appeared smaller in this study than in earlier studies. Clinical Trial

  9. Conductance relaxation in GeBiTe: Slow thermalization in an open quantum system

    Science.gov (United States)

    Ovadyahu, Z.

    2018-02-01

    This work describes the microstructure and transport properties of GeBixTey films with emphasis on their out-of-equilibrium behavior. Persistent-photoconductivity (PPC), previously studied in the phase-change compound GeSbxTey , is also quite prominent in this system. Much weaker PPC response is observed in the pure GeTe compound and when alloying GeTe with either In or Mn. Films made from these compounds share the same crystallographic structure, the same p -type conductivity, a similar compositional disorder extending over mesoscopic scales, and similar mosaic morphology. The enhanced photoconductive response exhibited by the Sb and Bi alloys may therefore be related to their common chemistry. Persistent photoconductivity is observable in GeBixTey films at the entire range of sheet resistances studied in this work (≈103Ω to ≈55 M Ω ). The excess conductance produced by a brief exposure to infrared illumination decays with time as a stretched exponential (Kohlrausch law). Intrinsic electron-glass effects, on the other hand, are observable in thin films of GeBixTey only for samples that are strongly localized just like it was noted with the seven electron glasses previously studied. These include a memory dip which is the defining attribute of the phenomenon. The memory dip in GeBixTey is the widest amongst the germanium-telluride alloys studied to date consistent with the high carrier concentration N ≥1021cm-3 of this compound. The thermalization process exhibited in either the PPC state or in the electron-glass regime is sluggish but the temporal law of the relaxation from the out-of-equilibrium state is distinctly different. Coexistence of the two phenomena give rise to some nontrivial effects, in particular, the visibility of the memory dip is enhanced in the PPC state. The relation between this effect and the dependence of the memory-effect magnitude on the ratio between the interparticle interaction and quench disorder is discussed.

  10. Enhanced relaxation of strained Ge{sub x}Si{sub 1-x} layers induced by Co/Ge{sub x}Si{sub 1-x} thermal reaction

    Energy Technology Data Exchange (ETDEWEB)

    Ridgway, M C; Elliman, R G; Rao, M R [Australian National Univ., Canberra, ACT (Australia); Baribeau, J M [National Research Council of Canada, Ottawa, ON (Canada)

    1994-12-31

    Enhanced relaxation of strained Ge{sub x}Si{sub l-x} layers during the formation of CoSi{sub 2} by Co/Ge{sub x}Si{sub 1-x} thermal reaction has been observed. Raman spectroscopy and transmission electron microscopy were used to monitor the extent of relaxation. Possible mechanisms responsible for the enhanced relaxation, including metal-induced dislocation nucleation, chemical and/or structural inhomogeneities at the reacted layer/Ge{sub x}Si{sub 1-x} interface and point defect injection due to silicide formation will be discussed. Also, methodologies for inhibiting relaxation will be presented. 11 refs., 1 fig.

  11. Enhanced relaxation of strained Ge{sub x}Si{sub 1-x} layers induced by Co/Ge{sub x}Si{sub 1-x} thermal reaction

    Energy Technology Data Exchange (ETDEWEB)

    Ridgway, M.C.; Elliman, R.G.; Rao, M.R. [Australian National Univ., Canberra, ACT (Australia); Baribeau, J.M. [National Research Council of Canada, Ottawa, ON (Canada)

    1993-12-31

    Enhanced relaxation of strained Ge{sub x}Si{sub l-x} layers during the formation of CoSi{sub 2} by Co/Ge{sub x}Si{sub 1-x} thermal reaction has been observed. Raman spectroscopy and transmission electron microscopy were used to monitor the extent of relaxation. Possible mechanisms responsible for the enhanced relaxation, including metal-induced dislocation nucleation, chemical and/or structural inhomogeneities at the reacted layer/Ge{sub x}Si{sub 1-x} interface and point defect injection due to silicide formation will be discussed. Also, methodologies for inhibiting relaxation will be presented. 11 refs., 1 fig.

  12. Game-based peripheral biofeedback for stress assessment in children.

    Science.gov (United States)

    Pop-Jordanova, Nada; Gucev, Zoran

    2010-06-01

    Peripheral biofeedback is considered to be an efficient method for assessment and stress mitigation in children. The aim of the present study was to assess the levels of stress and stress mitigation in healthy school children (HSC), in children with cystic fibrosis (CF), general anxiety (GA) and attention-deficit-hyperactivity disorder (ADHD). Each investigated group (HSC, CF, GA, ADHD) consisted of 30 school-aged children from both sexes. Psychological characteristics were evaluated on Eysenck Personality Questionnaire (EPQ). The lie scale was used to determine participant honesty. Four biofeedback games using a pulls detector were applied for assessment of the stress levels as well as to evaluate ability to relax. EPQ found more psychopathological traits (P Magic blocks score was significantly different in relaxation levels between control and CF children (P game Canal was significantly different in relaxation levels between healthy controls and all other groups, but no changes in pulls, as a relaxation measure, were found during the game. The CF group had much more commissions stemming from impulsivity (t= 5.71, P < 0.01), while the GA and ADHD children had more inattention omissions (P < 0.05). Strong negative correlation between age and pulls (r= 0.49, P= 0.003) and strong negative correlation between age and omissions (r=-0.86, P= 0.029) were found among all groups analyzed. The ability to learn stress mediation is correlated with age. All three groups of children had significantly lower relaxation levels when compared to healthy controls. Relaxation was more difficult for children with GA or ADHD, and easier for children with CF.

  13. Biofeedback & Bowel Disorders: Teaching Yourself to Live without the Problem

    Science.gov (United States)

    ... Medications Tips on Finding a Doctor What is biofeedback? Biofeedback is a neuromuscular reeducation tool therapists can ... to coordinate two responses more effectively. How can biofeedback help? Bowel control is a bodily function that ...

  14. Relaxation of thermal stress by dislocation motion in passivated metal interconnects

    NARCIS (Netherlands)

    Nicola, L; Van der Giessen, E; Needleman, A

    The development and relaxation of stress in metal interconnects strained by their surroundings (substrate and passivation layers) is predicted by a discrete dislocation analysis. The model is based on a two-dimensional plane strain formulation, with deformation fully constrained in the line

  15. Spin dynamics of Mn12-acetate in the thermally activated tunneling regime: ac susceptibility and magnetization relaxation

    Science.gov (United States)

    Pohjola, Teemu; Schoeller, Herbert

    2000-12-01

    In this work, we study the spin dynamics of Mn12-acetate molecules in the regime of thermally assisted tunneling. In particular, we describe the system in the presence of a strong transverse magnetic field. Similar to recent experiments, the relaxation time/rate is found to display a series of resonances; their Lorentzian shape is found to stem from the tunneling. The dynamic susceptibility χ(ω) is calculated starting from the microscopic Hamiltonian and the resonant structure manifests itself also in χ(ω). Similar to recent results reported on another molecular magnet, Fe8, we find oscillations of the relaxation rate as a function of the transverse magnetic field when the field is directed along a hard axis of the molecules. This phenomenon is attributed to the interference of the geometrical or Berry phase. We propose susceptibility experiments to be carried out for strong transverse magnetic fields to study these oscillations and for a better resolution of the sharp satellite peaks in the relaxation rates.

  16. Oculomotor biofeedback therapy for exotropia.

    Science.gov (United States)

    Goldrich, S G

    1982-04-01

    Twelve exotropes of various types received oculomotor biofeedback therapy at State College of New York (SUNY) University Optometric Center. Feedback of a variable pitch tone which reflected changes in ocular vergence reinforced motor control of eye posture. Patients were trained to achieve and sustain alignment in a variety of viewing situations. The six intermittent exotropes in the study who did not have amblyopia or prior history of unsuccessful surgical or orthoptic therapy achieved the highest recovery rating after training. The amblyope and those who had orthoptic training learned to voluntarily correct their eye position, although they did not achieve as acute a sensitivity to loss of alignment as did the others. Therapy restored eye control at near in a young constant exotrope whose condition resulted from severe neurological dysfunction. A constant postsurgical exotrope who had no ability for sensory fusion made little progress. Advantages of oculomotor biofeedback therapy are shorter treatment time, elimination of lengthy home training exercises, and enhanced patient motivation.

  17. Effect of thermal exposure on the residual stress relaxation in a hardened cylindrical sample under creep conditions

    Science.gov (United States)

    Radchenko, V. P.; Saushkin, M. N.; Tsvetkov, V. V.

    2016-05-01

    This paper describes the effect of thermal exposure (high-temperature exposure) ( T = 675°C) on the residual creep stress relaxation in a surface hardened solid cylindrical sample made of ZhS6UVI alloy. The analysis is carried out with the use of experimental data for residual stresses after micro-shot peening and exposures to temperatures equal to T = 675°C during 50, 150, and 300 h. The paper presents the technique for solving the boundary-value creep problem for the hardened cylindrical sample with the initial stress-strain state under the condition of thermal exposure. The uniaxial experimental creep curves obtained under constant stresses of 500, 530, 570, and 600 MPa are used to construct the models describing the primary and secondary stages of creep. The calculated and experimental data for the longitudinal (axial) tensor components of residual stresses are compared, and their satisfactory agreement is determined.

  18. Biofeedback and Communication: Perspectives and Definitions.

    Science.gov (United States)

    Rohm, C.E.; Goyer, R.S.

    This paper discusses the term "biofeedback" in its historical context and relates it to behavioral research in speech communication. The paper presents an operational model of the communication process, suggesting that biofeedback techniques might be used within the scope of the model to monitor, study, and ultimately modify an…

  19. The Comparative Study of the Occupational Stress among Jobs and Bio-Feedback Training Effects in Iran.

    Science.gov (United States)

    Kamarzarin, Hamid

    The effectiveness of biofeedback and relaxation training in reducing occupational stress was examined in a study of 50 individuals employed in various occupations in Iran. The study sample consisted of 15 workers (5 females, 10 males); 15 managers (5 females, 10 males); 9 guardians (3 females, 6 males); 5 dentists (2 females, 3 males); and 6…

  20. Origin of two maxima in specific heat in enthalpy relaxation under thermal history composed of cooling, annealing, and heating.

    Science.gov (United States)

    Sakatsuji, Waki; Konishi, Takashi; Miyamoto, Yoshihisa

    2016-12-01

    The origin of two maxima in specific heat observed at the higher and the lower temperatures in the glass-transition region in the heating process has been studied for polymethyl methacrylate and polyvinyl chloride using differential scanning calorimetry, and the calculation was done using the phenomenological model equation under a thermal history of the typical annealing experiment composed of cooling, annealing, and heating. The higher maximum is observed above the glass-transition temperature, and it remains almost unchanged independent of annealing time t_{a}, while the lower one is observed above an annealing temperature T_{a} and shifts toward the higher one, increasing its magnitude with t_{a}. The analysis by the phenomenological model equation proposed in order to interpret the memory effect in the glassy state clarifies that under a typical annealing history, two maxima in specific heat essentially appear. The shift of the lower maximum toward higher temperatures from above T_{a} is caused by an increase in the amount of relaxation during annealing with t_{a}. The annealing temperature and the amount of relaxation during annealing play a major role in the determination of the number of maxima in the specific heat.

  1. Review article: dyssynergic defaecation and biofeedback therapy in the pathophysiology and management of functional constipation.

    Science.gov (United States)

    Skardoon, G R; Khera, A J; Emmanuel, A V; Burgell, R E

    2017-08-01

    Functional constipation is a common clinical presentation in primary care. Functional defaecation disorders are defined as the paradoxical contraction or inadequate relaxation of the pelvic floor muscles during attempted defaecation (dyssynergic defaecation) and/or inadequate propulsive forces during attempted defaecation. Prompt diagnosis and management of dyssynergic defaecation is hindered by uncertainty regarding nomenclature, diagnostic criteria, pathophysiology and efficacy of management options such as biofeedback therapy. To review the evidence pertaining to the pathophysiology of functional defaecation disorders and the efficacy of biofeedback therapy in the management of patients with dyssynergic defaecation and functional constipation. Relevant articles addressing functional defaecation disorders and the efficacy of biofeedback therapy in the management of dyssynergic defaecation and functional constipation were identified from a search of Pubmed, MEDLINE Ovid and the Cochrane Library. The prevalence of dyssynergic defaecation in patients investigated for chronic constipation is as many as 40%. Randomised controlled trials have demonstrated major symptom improvement in 70%-80% of patients undergoing biofeedback therapy for chronic constipation resistant to standard medical therapy and have determined it to be superior to polyethylene glycol laxatives, diazepam or sham therapy. Long-term studies have shown 55%-82% of patients maintain symptom improvement. Dyssynergic defaecation is a common clinical condition in patients with chronic constipation not responding to conservative management. Biofeedback therapy appears to be a safe, successful treatment with sustained results for patients with dyssynergic defaecation. Further studies are required to standardise the diagnosis of dyssynergic defaecation in addition to employing systematic protocols for biofeedback therapy. © 2017 John Wiley & Sons Ltd.

  2. Biofeedback for psychiatric disorders: a systematic review.

    Science.gov (United States)

    Schoenberg, Poppy L A; David, Anthony S

    2014-06-01

    Biofeedback potentially provides non-invasive, effective psychophysiological interventions for psychiatric disorders. The encompassing purpose of this review was to establish how biofeedback interventions have been used to treat select psychiatric disorders [anxiety, autistic spectrum disorders, depression, dissociation, eating disorders, schizophrenia and psychoses] to date and provide a useful reference for consultation by clinicians and researchers planning to administer a biofeedback treatment. A systematic search of EMBASE, MEDLINE, PsycINFO, and WOK databases and hand searches in Applied Psychophysiology and Biofeedback, and Journal of Neurotherapy, identified 227 articles; 63 of which are included within this review. Electroencephalographic neurofeedback constituted the most investigated modality (31.7%). Anxiety disorders were the most commonly treated (68.3%). Multi-modal biofeedback appeared most effective in significantly ameliorating symptoms, suggesting that targeting more than one physiological modality for bio-regulation increases therapeutic efficacy. Overall, 80.9% of articles reported some level of clinical amelioration related to biofeedback exposure, 65.0% to a statistically significant (p biofeedback interventions within mainstream psychiatry.

  3. Analytical model of unsteady-state convective heat transfer between the heat carrier and the finite sizes plate adjusted for the thermal relaxation

    Directory of Open Access Journals (Sweden)

    Makarushkin Danila

    2017-01-01

    Full Text Available A hyperbolic boundary value problem of the thermal conduction of a two-dimensional plate with the third kind boundary conditions is formulated. The transient thermal process in the plate is due to the temperature changes of the external medium over time and along the plate length, and also by a multiple step change of the plate surface heat transfer coefficient throughout the transient process. An analytical solution with improved convergence adjusted for thermal relaxation and thermal damping is obtained for the temperature field in the plate.

  4. Relaxation of a coherent, magnetic s–p model system coupled to one and two thermal baths and a laser pulse

    Energy Technology Data Exchange (ETDEWEB)

    Lefkidis, G. [Department of Physics and Research Center OPTIMAS, University of Kaiserslautern, Box 3049, 67653 Kaiserslautern (Germany); School of Mechanics, Civil Engineering and Architecture, Northwestern Polytechnical University, Xi’an 710072 (China); Sold, S.; Hübner, W. [Department of Physics and Research Center OPTIMAS, University of Kaiserslautern, Box 3049, 67653 Kaiserslautern (Germany)

    2017-06-15

    We study an s–p model magnetic system with a triplet ground state coupled to two temperature baths. By varying the temperatures we both generate non-thermal electronic distributions and create additional coherences in the density matrix of the system. Thus the thermally-induced magnetic response goes beyond the simple picture of majority-minority population dynamics. Furthermore, we discuss the influence of temperature induced relaxation effects on the dynamics induced by an optical perturbation for this quantum system.

  5. Biofeedback in medicine: who, when, why and how?

    Science.gov (United States)

    2010-01-01

    Biofeedback is a mind–body technique in which individuals learn how to modify their physiology for the purpose of improving physical, mental, emotional and spiritual health. Much like physical therapy, biofeedback training requires active participation on the part of patients and often regular practice between training sessions. Clinical biofeedback may be used to manage disease symptoms as well as to improve overall health and wellness through stress management training. Research has shown that biofeedback interventions are efficacious in treating a variety of medical conditions, and many Americans are turning to biofeedback and other less traditional therapies for their routine healthcare. Clinical biofeedback training is growing increasingly popular in the USA, as many people are seeking out relatively new approaches to healthcare. This article provides an overview of clinical biofeedback training, outlines two models of training, details research which has established how effective biofeedback is in patients with a given disease, and describes who should be referred for biofeedback training. PMID:22477926

  6. Randomised trial of biofeedback training for encopresis

    NARCIS (Netherlands)

    van der Plas, R. N.; Benninga, M. A.; Redekop, W. K.; Taminiau, J. A.; Büller, H. A.

    1996-01-01

    To evaluate biofeedback training in children with encopresis and the effect on psychosocial function. Prospective controlled randomised study. PATIENT INTERVENTIONS: A multimodal treatment of six weeks. Children were randomised into two groups. Each group received dietary and toilet advice, enemas,

  7. BIOFEEDBACK THERAPY FOR CONSTIPATION IN ADULTS

    Science.gov (United States)

    Rao, Satish S.C.

    2011-01-01

    Dyssynergic defecation is common and affects up to one half of patients with chronic constipation. This acquired behavioral problem is due to the inability to coordinate the abdominal and pelvic floor muscles to evacuate stools. Today, it is possible to diagnose this problem and treat this effectively with biofeedback therapy, history, prospective stool diaries, and anorectal physiological tests. Several randomized controlled trails have demonstrated that biofeedback therapy using neuromuscular training and visual and verbal feedback is not only efficacious but superior to other modalities such as laxative or sham training. Also the symptom improvement is due a change in the underlying pathophysiology. Development of user friendly approaches to biofeedback therapy and use of home biofeedback programs will significantly enhance the adoption of this treatment by gastroenterologists and colorectal surgeons in the future. Improved reimbursement for this proven and relatively inexpensive treatment will carry a significant impact on the problem. PMID:21382587

  8. Biofeedback in the treatment of heart failure.

    Science.gov (United States)

    McKee, Michael G; Moravec, Christine S

    2010-07-01

    Biofeedback training can be used to reduce activation of the sympathetic nervous system (SNS) and increase activation of the parasympathetic nervous system (PNS). It is well established that hyperactivation of the SNS contributes to disease progression in chronic heart failure. It has been postulated that underactivation of the PNS may also play a role in heart failure pathophysiology. In addition to autonomic imbalance, a chronic inflammatory process is now recognized as being involved in heart failure progression, and recent work has established that activation of the inflammatory process may be attenuated by vagal nerve stimulation. By interfering with both autonomic imbalance and the inflammatory process, biofeedback-assisted stress management may be an effective treatment for patients with heart failure by improving clinical status and quality of life. Recent studies have suggested that biofeedback and stress management have a positive impact in patients with chronic heart failure, and patients with higher perceived control over their disease have been shown to have better quality of life. Our ongoing study of biofeedback-assisted stress management in the treatment of end-stage heart failure will also examine biologic end points in treated patients at the time of heart transplant, in order to assess the effects of biofeedback training on the cellular and molecular components of the failing heart. We hypothesize that the effects of biofeedback training will extend to remodeling the failing human heart, in addition to improving quality of life.

  9. Using music as a signal for biofeedback.

    Science.gov (United States)

    Bergstrom, Ilias; Seinfeld, Sofia; Arroyo-Palacios, Jorge; Slater, Mel; Sanchez-Vives, Maria V

    2014-07-01

    Studies on the potential benefits of conveying biofeedback stimulus using a musical signal have appeared in recent years with the intent of harnessing the strong effects that music listening may have on subjects. While results are encouraging, the fundamental question has yet to be addressed, of how combined music and biofeedback compares to the already established use of either of these elements separately. This experiment, involving young adults (N = 24), compared the effectiveness at modulating participants' states of physiological arousal of each of the following conditions: A) listening to pre-recorded music, B) sonification biofeedback of the heart rate, and C) an algorithmically modulated musical feedback signal conveying the subject's heart rate. Our hypothesis was that each of the conditions (A), (B) and (C) would differ from the other two in the extent to which it enables participants to increase and decrease their state of physiological arousal, with (C) being more effective than (B), and both more than (A). Several physiological measures and qualitative responses were recorded and analyzed. Results show that using musical biofeedback allowed participants to modulate their state of physiological arousal at least equally well as sonification biofeedback, and much better than just listening to music, as reflected in their heart rate measurements, controlling for respiration-rate. Our findings indicate that the known effects of music in modulating arousal can therefore be beneficially harnessed when designing a biofeedback protocol. Copyright © 2013 Elsevier B.V. All rights reserved.

  10. Biofeedback

    Science.gov (United States)

    ... physical and mental health issues, including: Anxiety or stress Asthma Attention deficit hyperactivity disorder (ADHD) Chemotherapy side effects Chronic pain Constipation Fecal incontinence Fibromyalgia Headache High blood pressure Irritable bowel syndrome Motion sickness ...

  11. On the Effects of Thermal History on the Development and Relaxation of Thermo-Mechanical Stress in Cryopreservation.

    Science.gov (United States)

    Eisenberg, David P; Steif, Paul S; Rabin, Yoed

    2014-01-01

    This study investigates the effects of the thermal protocol on the development and relaxation of thermo-mechanical stress in cryopreservation by means of glass formation, also known as vitrification. The cryopreserved medium is modeled as a homogeneous viscoelastic domain, constrained within either a stiff cylindrical container or a highly compliant bag. Annealing effects during the cooling phase of the cryopreservation protocol are analyzed. Results demonstrate that an intermediate temperature-hold period can significantly reduce the maximum tensile stress, thereby decreasing the potential for structural damage. It is also demonstrated that annealing at temperatures close to glass transition significantly weakens the dependency of thermo-mechanical stress on the cooling rate. Furthermore, a slower initial rewarming rate after cryogenic storage may drastically reduce the maximum tensile stress in the material, which supports previous experimental observations on the likelihood of fracture at this stage. This study discusses the dependency of the various stress components on the storage temperature. Finally, it is demonstrated that the stiffness of the container wall can affect the location of maximum stress, with implications on the development of cryopreservation protocols.

  12. Thermal dissociation and relaxation in vinyl fluoride, 1,1-difluoroethane and 1,3,5-triazine

    Science.gov (United States)

    Xu, Hui

    This study reports measurements of the thermal dissociation of 1,1-difluoroethane in the shock tube. The experiments employ laser schlieren measurements of rate for the dominant HF elimination using 10% 1,1-difluoroethane in Kr over 1500--2000 K and 43 difluoroethane based on a G3B3 calculation of barrier and other properties fits the experiments but requires a very large down of 1600cm-1 . Dissociation of vinyl fluoride has two parallel HF eliminations both three-center and four-center with nearly equal barriers. An RRKM fit to the observed falloff again requires an unusually large down and the experiments actually support a slightly reduced barrier. Both 1,3,5-triazine and pyrazine relax extremely rapidly with energy transfer in a few collisions, any incubation delay can be confidently discounted in dissociation. 1,3,5-triazine dissociation experiments show fall-off with a clear pressure dependence. The three body product dissociation mechanism models this dissociation perfectly. Experimental data agree well with an RRKM calculation using a down of 1200cm-1 and a barrier E0 = 84.66 kcal/mol. Dyakov et al. suggested lower barrier of E0 = 81 kcal/mole. The new RRKM calculation using this barrier seems a better fit to the experiments. The falloff is now fit well with a down of the more usual form 126(T/298) 0-9 cm-1.

  13. Efficacy of biofeedback therapy via a mini wireless device on sleep bruxism contrasted with occlusal splint: a pilot study

    Science.gov (United States)

    Gu, WeiPing; Yang, Jie; Zhang, FeiMin; Yin, XinMin; Wei, XiaoLong; Wang, Chen

    2015-01-01

    Abstract The putative causes of bruxism are multifactorial and there are no definite measures for bruxism management. The aim of this study was to evaluate the efficacy of biofeedback therapy on sleep bruxism, compared with occlusal splint. Twenty-four volunteers with sleep bruxism were divided into two groups: the GTB group that were treated with biofeedback therapy (n  = 12) and the GTO group that were treated with occlusal splint (n  = 12). A mini pressure sensor integrated with a monitoring circuit by use of a maxillary biofeedback splint was fabricated. To foster the relaxation of the masticatory muscles and the nervous system, the wireless device received signals from bruxism events and vibrations alerted the bruxer when the threshold was exceeded. Total episodes and average duration of bruxism events during 8 hours of sleep were analyzed with the monitoring program (TRMY1.0). After 6 and 12 weeks, the episodes (P  =  0.001) and duration (P 0.05). Furthermore, the episodes had significant differences between the GTB group and the GTO group after the same period of treatment (P  =  0.000). The results suggest that biofeedback therapy may be an effective and convenient measure for mild bruxers, when compared with occlusal splint therapy. The mini wireless biofeedback method may be of value for the diagnosis and management of bruxism in the future. PMID:25859272

  14. Elucidation of thermal hydraulic mixing mechanism in a mixing tee area with a 90-degree bend upstream and development of thermal-striping relaxation and control methods

    International Nuclear Information System (INIS)

    Sugawara, Yoshimasa; Yuki, Kazuhisa; Hashizume, Hidetoshi; Tanaka, Masa-aki; Muramatsu, Toshiharu

    2004-10-01

    In the region where two fluids with different temperatures mix, unstable fluid mixing like thermal striping occurs accompanying with unsteady temperature fluctuation of fluid. This temperature fluctuation is transported toward the surrounding area and becomes an important factor that induces thermal fatigue of structural materials, which sometimes results in crack generation of them. In fast breeder reactors that utilize liquid sodium as a coolant, the fluid temperature fluctuation could be easier to conduct toward the structural materials due to its high thermal conductivity, so that careful consideration for the thermal fatigue is required. In particular, since the low frequency band of temperature fluctuation strongly affects the thermal fatigue, evaluation and development of the relaxation and control methods for it become important issues. In this study, non-isothermal fluid mixing experiments in a T-junction area with a 90-degree bend upstream were carried out to estimate the fluid-temperature fluctuation in the vicinity of wall. The temperature fluctuations for various flow mixing conditions were measured, changing a velocity ratio and a pipe diameter ratio of a main pipe to a branch pipe to quantitatively evaluate the effect of a secondary flow on the temperature fluctuation. In addition, by analyzing both the visualization data taken by a PIV system and the temperature fluctuation data, it was attempted to construct a prediction formula for the temperature fluctuation. Our findings are summarized below. (1) Classifying the flow mixing pattern of jet flow running out from the branch pipe makes it possible to predict the maximum temperature fluctuation in the mixing area with higher accuracy by using the flow velocity ratio (0.2 -0.06 (d/D) 0.22 . Re-attachment Flow - deflecting Flow: Max(ΔTrms*)=0.64(v/V) -0.92 (d/D) 1.11 . (2) Prediction formulas for the maximum temperature fluctuation in the case of the curvature ratio of 1.0 are also constructed as

  15. Thermal Fluctuations in the Magnetic Ground State of the Molecular Cluster Mn12O12 Acetate from μSR and Proton NMR Relaxation

    International Nuclear Information System (INIS)

    Lascialfari, A.; Borsa, F.; Carretta, P.; Jang, Z.H.; Borsa, F.; Gatteschi, D.

    1998-01-01

    Measurements of the spin-lattice relaxation rate are reported for muons and protons as a function of temperature for different values of the applied magnetic field in the Mn 12 O 12 molecular cluster. Strongly field dependent maxima in the relaxation rate versus temperature are observed below 50thinspthinspK. The results are explained in terms of thermal fluctuations of the total magnetization of the cluster among the different orientations with respect to the anisotropy axis. The lifetimes of the different m components of the total spin, S T =10 , of the molecule are obtained from the experiment and shown to be consistent with the ones expected from a spin-phonon coupling mechanism. No clear evidence for macroscopic quantum tunneling was observed in the field dependence of the proton relaxation rate at low T . copyright 1998 The American Physical Society

  16. Audiovisual biofeedback improves motion prediction accuracy.

    Science.gov (United States)

    Pollock, Sean; Lee, Danny; Keall, Paul; Kim, Taeho

    2013-04-01

    The accuracy of motion prediction, utilized to overcome the system latency of motion management radiotherapy systems, is hampered by irregularities present in the patients' respiratory pattern. Audiovisual (AV) biofeedback has been shown to reduce respiratory irregularities. The aim of this study was to test the hypothesis that AV biofeedback improves the accuracy of motion prediction. An AV biofeedback system combined with real-time respiratory data acquisition and MR images were implemented in this project. One-dimensional respiratory data from (1) the abdominal wall (30 Hz) and (2) the thoracic diaphragm (5 Hz) were obtained from 15 healthy human subjects across 30 studies. The subjects were required to breathe with and without the guidance of AV biofeedback during each study. The obtained respiratory signals were then implemented in a kernel density estimation prediction algorithm. For each of the 30 studies, five different prediction times ranging from 50 to 1400 ms were tested (150 predictions performed). Prediction error was quantified as the root mean square error (RMSE); the RMSE was calculated from the difference between the real and predicted respiratory data. The statistical significance of the prediction results was determined by the Student's t-test. Prediction accuracy was considerably improved by the implementation of AV biofeedback. Of the 150 respiratory predictions performed, prediction accuracy was improved 69% (103/150) of the time for abdominal wall data, and 78% (117/150) of the time for diaphragm data. The average reduction in RMSE due to AV biofeedback over unguided respiration was 26% (p biofeedback improves prediction accuracy. This would result in increased efficiency of motion management techniques affected by system latencies used in radiotherapy.

  17. A Comparison of Meditation with Other Relaxation Techniques.

    Science.gov (United States)

    Fling, Sheila

    This paper critiques a negative 1984 review, "Meditation and Somatic Arousal Reduction" (Holmes), on the absolute effectiveness of meditation in reducing somatic arousal and reviews research on the relative effectiveness of meditation compared to techniques such as biofeedback, hypnosis, progressive muscle relaxation, and autogenics in…

  18. Biofeedback Training for Peak Performance in Sport - Case Study

    OpenAIRE

    Pop-Jordanova, Nada; Demerdzieva, Aneta

    2017-01-01

    The use of peripheral biofeedback and neurofeedback is growing rapidly in sport psychology. The aim is to lower competition stress, anxiety, and muscle tension.We present a case report concerned to biofeedback training in an athlete in preparation to Olympic Game competition. It is the first case in our region to prepare athlete with biofeedback modalities. Obtained results are very encouraging.

  19. EMG Biofeedback Training Versus Systematic Desensitization for Test Anxiety Reduction

    Science.gov (United States)

    Romano, John L.; Cabianca, William A.

    1978-01-01

    Biofeedback training to reduce test anxiety among university students was investigated. Biofeedback training with systematic desensitization was compared to an automated systematic desensitization program not using EMG feedback. Biofeedback training is a useful technique for reducing test anxiety, but not necessarily more effective than systematic…

  20. Differential Effectiveness of Electromyograph Feedback, Verbal Relaxation Instructions, and Medication Placebo with Tension Headaches

    Science.gov (United States)

    Cox, Daniel J.; And Others

    1975-01-01

    Adults with chronic tension headaches were assigned to auditory electromyograph (EMG) feedback (N=9), to progressive relaxation (N=9), and to placebo treatment (N=9). Data indicated that biofeedback and verbal relaxation instructions were equally superior to the medicine placebo on all measured variables in the direction of clinical improvement,…

  1. BIOFEEDBACK TRAINING AND TENSION-TYPE HEADACHE.

    Science.gov (United States)

    Šecić, Ana; Cvjeticanin, Timon; Kes, Vanja Bašić

    2016-03-01

    Biofeedback is a training method, which connects physiological and psychological processes in a person for the purposes of improving his/her physical, emotional, mental and spiritual health. In biofeedback treatment, an active role of the patient is stressed for him/her to be able to actively control the physiological and emotional processes. The aim of biofeedback is to improve the conscious control of the individual's involuntary physiological activity. Research has shown that biofeedback, either applied alone or in combination with other behavioral therapies (techniques), is an effective treatment for various medical and psychological disorders, from headache and hypertension to temporomandibular and attention deficit disorders. More than 90% of adults experience headache once a year, which makes headache one of the most common symptoms and diagnoses in medicine. Tension-type headaches occur in at least 40% of the population and their impact on the health insurance costs and diminished productivity is significant. Studies have shown that clinical biofeedback training is effective in treating headaches. Moreover, the authors stress the need for additional research and further development of methodology for this kind of research.

  2. Relaxation of Anisotropic Glasses

    DEFF Research Database (Denmark)

    Deubener, Joachim; Martin, Birgit; Wondraczek, Lothar

    2004-01-01

    . When the load was removed at room temperature a permanent optical anisotropy (birefringence) was observed only perpendicular to cylinder axis and the pressure direction indicating complete elimination of thermal stresses. Relaxation of structural anisotropy was studied from reheating experiments using...... the energy release, thermo-mechanical and optical relaxation behaviour are drawn....

  3. {CoIII2DyIII2} single molecule magnet with two resolved thermal activated magnetization relaxation pathways at zero field.

    Science.gov (United States)

    Funes, Alejandro V; Carrella, Luca; Rentschler, Eva; Alborés, Pablo

    2014-02-14

    The new complex [Co(III)2Dy(III)2(OMe)2(teaH)2(Piv)6] in the {Co(III)2Dy(III)2} family, shows two well resolved thermal activated magnetization relaxation pathways under AC experiments in zero DC field. Fitted crystal field parameters suggest that the origin of these two pathways relies on two different excited mJ sub-levels.

  4. Biofeedback in psychomotor training. Electrophysiological basis.

    Science.gov (United States)

    Bazanova, O M; Mernaya, E M; Shtark, M B

    2009-06-01

    The influences of individual musical practice and the same practice supplemented with biofeedback using electrophysiological markers for optimum music-performing activity were studied in 39 music students. Traditional technical practice produced increases in integral EMG power and decreases in alpha activity in most of the students with initially low maximum alpha activity peak frequencies. Similar practice but combined with individual sessions of alpha-EEG/EMG biofeedback were accompanied by increases in the frequency, bandwidth, and activation responses of EEG alpha rhythms in all subjects, along with decreases in EEG integral power. The efficacy of training with biofeedback and the ability to experience psychomotor learning depended on the initial individual characteristics of EEG alpha activity.

  5. [Biofeedback in psychomotor training. Electrophysiological bases].

    Science.gov (United States)

    Bazanova, O M; Mernaia, E M; Shtark, M B

    2008-05-01

    Comparison of influence of usual musical practice and the same trainings but using biofeedback on electrophysiological and psychological markers of optimal psychomotor functioning in 39 students-musicians revealed that the obvious musical practice caused psychomotor pressure in most students (with initially low individual alpha peak frequency), whereas similar practice combined with an individualized session of alpha-EEG/EMG biofeedback was accompanied by increase of alpha-activity in all examinees and a decrease (reduction) of integrated EMG that indicated reaching of optimal psychomotor functioning. It appears that the psychomotor learning ability depends on the baseline individual alpha-activity. Individual alpha peak frequency was associated with fluency and efficiency of psychomotor performance, individual alpha band width--with plasticity and creativity, individual amount of alpha suppression in response to opening eyes--with the level of selfactualization. These alpha activity EEG indices correlated with efficiency of the biofeedback training.

  6. Microperimetric biofeedback training: fundamentals, strategies and perspectives.

    Science.gov (United States)

    Vingolo, Enzo Maria; Napolitano, Giuseppe; Fragiotta, Serena

    2018-01-01

    Microperimetric biofeedback training (MBFT) is a visual rehabilitative strategy based on fixation stability improvement reinforcing or creating a new preferential fixation locus. The rationale consists in reeducating visual system to a new visual condition, promoting retina-brain transmission, and thus cortical plasticity. The use of MBFT found is major application in visual diseases involving central vision, but later it revealed promising functional outcomes even in myopia, inherited retinal degenerations and nystagmus. However, the use of microperimetric biofeedback is still limited due to poor knowledge of the procedure and inconsistent standards of practice, and thus an incipient skepticism on its efficacy. This review provides an overview of the rationale, current implications, procedures and future perspectives of microperimetric biofeedback training.

  7. Influence of aging time of oleate precursor on the magnetic relaxation of cobalt ferrite nanoparticles synthesized by the thermal decomposition method

    International Nuclear Information System (INIS)

    Herrera, Adriana P.; Polo-Corrales, Liliana; Chavez, Ermides; Cabarcas-Bolivar, Jari; Uwakweh, Oswald N.C.; Rinaldi, Carlos

    2013-01-01

    Cobalt ferrite nanoparticles are of interest because of their room temperature coercivity and high magnetic anisotropy constant, which make them attractive in applications such as sensors based on the Brownian relaxation mechanism and probes to determine the mechanical properties of complex fluids at the nanoscale. These nanoparticles can be synthesized with a narrow size distribution by the thermal decomposition of an iron–cobalt oleate precursor in a high boiling point solvent. We studied the influence of aging time of the iron–cobalt oleate precursor on the structure, chemical composition, size, and magnetic relaxation of cobalt ferrite nanoparticles synthesized by the thermal decomposition method. The structure and thermal behavior of the iron–cobalt oleate was studied during the aging process. Infrared spectra indicated a shift in the coordination state of the oleate and iron/cobalt ions from bidentate to bridging coordination. Aging seemed to influence the thermal decomposition of the iron–cobalt oleate as determined from thermogravimmetric analysis and differential scanning calorimetry, where shifts in the temperatures corresponding to decomposition events and a narrowing of the endotherms associated with these events were observed. Aging promoted formation of the spinel crystal structure, as determined from X-ray diffraction, and influenced the nanoparticle magnetic properties, resulting in an increase in blocking temperature and magnetocrystalline anisotropy. Mossbauer spectra also indicated changes in the magnetic properties resulting from aging of the precursor oleate. Although all samples exhibited some degree of Brownian relaxation, as determined from complex susceptibility measurements in a liquid medium, aging of the iron–cobalt oleate precursor resulted in crossing of the in-phase χ′and out-of-phase χ″ components of the complex susceptibility at the frequency of the Brownian magnetic relaxation peak, as expected for nanoparticles

  8. Biofeedback, voluntary control, and human potential.

    Science.gov (United States)

    Norris, P

    1986-03-01

    This paper examines some of the philosophical and scientific relationships involving self-control, voluntary control, and psychophysiologic self-regulation. The role of biofeedback in mediating conscious and unconscious processes is explored. Demonstrations of superior voluntary control and its relationship to belief, confidence, and expectation are examined. Biofeedback demonstrates the potential of control to oneself, creating confidence in one's ability to establish enhanced and peak performance in athletics, education, and psychophysiologic therapy. Emphasis is placed on the power of images in all human functioning, and in enhancing human potential.

  9. [Biofeedback in young singer vocal training].

    Science.gov (United States)

    Ciochină, Paula; Ciochină, Al D; Burlui, Ada; Zaharia, D

    2007-01-01

    Biofeedback therapy is a learning process that is based on "operant conditioning" techniques. To estimate the significance of biofeedback to an accurate and faster control of singing voice emission. Significantly, it was discovered that professional singers active in performing of both classical and music theatre repertoire with regard to the visual-kinesthetic effect of melodic contour in musical notation as it affect vocal timbre. The results of the study also indicate that the development of new technology for youth singer vocal training, may be useful to these singers.

  10. Biofeedback defaecation training for anismus.

    Science.gov (United States)

    Lestàr, B; Penninckx, F; Kerremans, R

    1991-11-01

    Anismus, paradoxical external sphincter function, spastic pelvic floor syndrome, rectoanal dysnergia, abdomino-levator incoordination for abdominopelvic asychronism, are all due to paradoxical contraction of the striated sphincter apparatus during voiding and is characterised by prolonged and excessive straining at stool. Biofeedback is the treatment of choice and has to be introduced at an early stage. We present the results of an ambulatory approach based on the integration of simulated balloon defaecation with small (50 ml) as well as constant rectal sensation volume, defaecometry and anal manometry. The pathophysiology visualised by the patient's own anorectal pressure recordings on the screen of a personal computer is explained and corrected. Sixteen patients were treated and followed for at least 1 year. Manometric data were normal except for an increased minimum residual pressure and rectal compliance. Nine patients could not evacuate a 50 ml bolus initially. Simulated defaecation became possible in seven out of these nine patients when the bolus was increased up to the individual constant rectal sensation volume. Two patients could not evacuate this volume either, while defaecation was made much less laborious in the other seven patients. Paradoxical contraction was immediately corrected in 7/16 cases. Also, as an immediate, objective benefit of a single training session, improved defaecation of a 50 ml bolus was observed in 11 patients. This effect was preserved after 6 weeks in nine cases; symptomatic recurrence did not occur in these patients during follow-up. This method of defaecation training has many advantages as compared with sphincter training using EMG electrodes eventually performed in the absence of a desire to defaecate or in lying position.(ABSTRACT TRUNCATED AT 250 WORDS)

  11. Electron-mediated relaxation following ultrafast pumping of strongly correlated materials: model evidence of a correlation-tuned crossover between thermal and nonthermal states.

    Science.gov (United States)

    Moritz, B; Kemper, A F; Sentef, M; Devereaux, T P; Freericks, J K

    2013-08-16

    We examine electron-electron mediated relaxation following ultrafast electric field pump excitation of the fermionic degrees of freedom in the Falicov-Kimball model for correlated electrons. The results reveal a dichotomy in the temporal evolution of the system as one tunes through the Mott metal-to-insulator transition: in the metallic regime relaxation can be characterized by evolution toward a steady state well described by Fermi-Dirac statistics with an increased effective temperature; however, in the insulating regime this quasithermal paradigm breaks down with relaxation toward a nonthermal state with a complicated electronic distribution as a function of momentum. We characterize the behavior by studying changes in the energy, photoemission response, and electronic distribution as functions of time. This relaxation may be observable qualitatively on short enough time scales that the electrons behave like an isolated system not in contact with additional degrees of freedom which would act as a thermal bath, especially when using strong driving fields and studying materials whose physics may manifest the effects of correlations.

  12. Randomised trial of biofeedback training for encopresis.

    Science.gov (United States)

    van der Plas, R N; Benninga, M A; Redekop, W K; Taminiau, J A; Büller, H A

    1996-01-01

    AIMS: To evaluate biofeedback training in children with encopresis and the effect on psychosocial function. DESIGN: Prospective controlled randomised study. PATIENT INTERVENTIONS: A multimodal treatment of six weeks. Children were randomised into two groups. Each group received dietary and toilet advice, enemas, oral laxatives, and anorectal manometry. One group also received five biofeedback training sessions. MAIN OUTCOME MEASURES: Successful treatment was defined as less than two episodes of encopresis, regular bowel movements, and no laxatives. Psychosocial function after treatment was assessed using the Child Behaviour Checklist. RESULTS: Children given laxatives and biofeedback training had higher success rates than those who received laxatives alone (39% v 19%) at the end of the intervention period. At 12 and 18 months, however, approximately 50% of children in each group were successfully treated. Abnormal behaviour scores were initially observed in 35% of children. Most children had improved behaviour scores six months after treatment. Children with an initial abnormal behaviour score who were successfully treated had a significant improvement in their behavioural profiles. CONCLUSIONS: Biofeedback training had no additional effect on the success rate or behaviour scores. Psychosocial problems are present in a subgroup of children with encopresis. The relation between successful treatment and improvement in behavioural function supports the idea that encopresis has an aetiological role in the occurrence and maintenance of behavioural problems in children with encopresis. PMID:8957948

  13. [Biofeedback effectiveness in patients with fecal incontinence].

    Science.gov (United States)

    Guerra-Mora, José Raúl; Buenrostro-Acebes, José María; Erciga-Vergara, Nancy; Zubieta-O'Farrill, Gregorio; Castillo-Calcáneo, Juan de Dios; Mosqueda, Maria Elena; Monroy-Argumedo, Montserrat; González-Alvarado, Carlos; Villanueva-Saenz, Eduardo

    2015-01-01

    Fecal incontinence is defined as an involuntary bowel movement through the anal canal in inadequate time and place. There are different types of therapies for the management of fecal incontinence, being biofeedback therapy one of the most effective techniques. The aim of this study was to evaluate the necessary number of sessions of biofeedback electromyographyc therapy to achieve the maximum sphincteric complex contraction. Descriptive, retrospective and longitudinal study. 65 patients with fecal incontinence were included. Weekly electromyographyc biofeedback therapies were applied, with a maximum of 6, in which the sphincteric complex contraction was measured. A two ways Friedman analysis was made to determine the significant differences between the sessions. A total of 65 patients were evaluated for fecal incontinence. The values for pelvic floor contraction were significantly higher in the third session, and did not show any significant difference in posterior sessions. The maximum contraction of the sphicnteric complex was achieved in the third weekly biofeedback session, without any significant differences in the posterior sessions.

  14. Pelvic floor dyssynergia: efficacy of biofeedback training.

    Science.gov (United States)

    Gadel Hak, Nabil; El-Hemaly, Mohamed; Hamdy, Emad; El-Raouf, Ahmed Abd; Atef, Ehab; Salah, Tarek; El-Hanafy, Ehab; Sultan, Ahmad; Haleem, Magdy; Hamed, Hala

    2011-03-01

    Paradoxical contraction of the pelvic floor during attempts to defaecate is described as pelvic floor dyssynergia (anismus). It is a behavioural disorder (no associated morphological or neurological abnormalities); consequently, biofeedback training has been recommended as a behavioural therapy for such a disorder. The aim of the present study was to evaluate long-term satisfaction of patients diagnosed with pelvic floor dyssynergia after biofeedback. Sixty patients (35 females and 25 males) with a mean age of 30±12years and a 4year duration of constipation were included. Forty-five patients had normal colonic transit and 15 patients had slow colonic transit. History, physical examination and barium enema were done to exclude constipation secondary to organic causes. Colonic and pelvic floor functions (colon-transit time, anorectal manometry, EMG and defaecography) were performed before and after biofeedback treatments. Patients were treated on a weekly basis with an average of (6±2) sessions. At the end of sessions, 55 out of 60 patients (91.6%) reported a subjectively overall improvement. Symptoms of dyschezia were reported less frequently after biofeedback. Age and gender were not predictive factors of outcome. No symptoms at initial assessment were predictive for patient's satisfaction but the only factor of predictive value was the diagnosis of anismus and the motivated patient who wanted to continue the sessions. Biofeedback remains a morbidity free, low-cost and effective outpatient therapy for well-motivated patients complaining of functional constipation and diagnosed as pelvic floor dyssynergia. Copyright © 2011 Arab Journal of Gastroenterology. Published by Elsevier Ltd. All rights reserved.

  15. Biofeedback systems and adaptive control hemodialysis treatment

    Directory of Open Access Journals (Sweden)

    Azar Ahmad

    2008-01-01

    Full Text Available On-line monitoring devices to control functions such as volume, body temperature, and ultrafiltration, were considered more toys than real tools for routine clinical application. However, bio-feedback blood volume controlled hemodialysis (HD is now possible in routine dialysis, allowing the delivery of a more physiologically acceptable treatment. This system has proved to reduce the incidence of intra-HD hypotension episodes significantly. Ionic dialysance and the patient′s plasma conductivity can be calculated easily from on-line measurements at two different steps of dialysate conductivity. A bio-feedback system has been devised to calculate the patient′s plasma conductivity and modulate the conductivity of the dialysate continuously in order to achieve a desired end-dialysis patient plasma conductivity corresponding to a desired end-dialysis plasma sodium concentration. Another bio-feedback system can control the body tempe-rature by measuring it at the arterial and venous lines of the extra-corporeal circuit, and then modulating the dialysate temperature in order to stabilize the patients′ temperature at constant values that result in improved intra-HD cardiovascular stability. The module can also be used to quantify vascular access recirculation. Finally, the simultaneous computer control of ultrafiltration has proven the most effective means for automatic blood pressure stabilization during hemo-dialysis treatment. The application of fuzzy logic in the blood-pressure-guided biofeedback con-trol of ultrafiltration during hemodialysis is able to minimize HD-induced hypotension. In con-clusion, online monitoring and adaptive control of the patient during the dialysis session using the bio-feedback systems is expected to render the process of renal replacement therapy more physiological and less eventful.

  16. Biofeedback therapy for chronic constipation in a patient with Prader-Willi syndrome.

    Science.gov (United States)

    Corral, Juan E; Kataria, Rahul; Vickers, Dawn; Koutouby, Raghad; Moshiree, Baharak

    2015-01-01

    Constipation is a common feature of Prader-Willi syndrome. Research exploring the prevalence, cause and treatment options for constipation is limited and lacks objective measurements such as anorectal manometry. We report a case of a 16-year-old lady with Prader-Willi syndrome presenting with rectal pain and constipation for 2 years despite multiple medications and weekly enemas. She also noted passive fecal incontinence that required frequent manual disimpactions. Anorectal manometry revealed an abnormal relaxation of the puborectalis and external sphincter muscles on push maneuvers suggesting dyssynergic defecation and rectal hypersensitivity. Contraction and relaxation of her pelvic muscles were recorded with electromyography. Relaxation of the puborectalis muscle improved significantly after three biofeedback sessions. Patient was successfully tapered off laxatives and has been maintained on linaclotide only. Dyssynergic defecation may be a common finding in Prader-Willi syndrome. In selected cases we recommend anorectal manometry to identify neuromuscular dysfunction and subsequent biofeedback therapy depending on the degree of mental retardation to minimize overuse of laxatives.

  17. A model of group cognitive behavioral intervention combined with bio-feedback in oncology settings.

    Science.gov (United States)

    Cohen, Miri

    2010-01-01

    This article's goal is to present a model for social work with cancer patients and their relatives aimed at teaching ways of coping with cancer and its implications. The article presents a model of six meetings, emphasizing learning processes and acquisition of skills enabling participants to recognize and change distressing thoughts, combined with learning relaxation methods and guided imagery. An additional unique property of this model is the bio-feedback, which assists in creating awareness of physiological alertness states and in learning and implementing the different methods for decreasing pressure and stress.

  18. Efficacy of functional electrical stimulation-biofeedback with sexual cognitive-behavioral therapy as treatment of vaginismus.

    Science.gov (United States)

    Seo, Ju Tae; Choe, Jin Ho; Lee, Won Sik; Kim, Kyung Hee

    2005-07-01

    To report 12 cases of vaginismus that were successfully treated with functional electrical stimulation (FES)-biofeedback with sexual cognitive-behavioral therapy (SCBT) to determine the efficacy of FES-biofeedback with SCBT as a standard therapy for vaginismus. Vaginismus is an involuntary spasm of the musculature of the outer third of the vagina that leads to impossible vaginal penetration, causing personal distress. Various therapeutic approaches, both physiologic and psychological, have been considered. Twelve women with vaginismus referred from a checkup outpatient clinic participated in this study. The patients enrolled in this study had vaginismus according to the criteria of the Diagnostic and Statistical Manual of Mental Disorders. The patients were assessed before and after treatment with gynecologic examinations and structured interviews pertaining to sexual function and psychological adjustment. After the diagnosis of vaginismus, we conducted weekly pelvic floor muscle relaxation using FES-biofeedback. Once the patients became tolerable to vaginal manipulation, the eight-stage SCBT (eight-stage gradual desensitization described by Kaplan using vaginal self-dilation with fingers and vaginal probe insertion) was added for 8 weeks. After 8 weeks of treatment, all 12 couples had completed the program, had become tolerable to vaginal insertion of larger size probes, and could achieve satisfactory vaginal intercourse. FES-biofeedback with SCBT is an effective aid for patients with vaginismus to learn muscle control. Therefore, it may increase the success rate of treatment of vaginismus.

  19. Biofeedback for anismus in 15 sexually abused women.

    Science.gov (United States)

    Leroi, A M; Duval, V; Roussignol, C; Berkelmans, I; Peninque, P; Denis, P

    1996-01-01

    This work aimed to see whether (1) biofeedback is useful and (2) whether it needs to be combined with psychotherapy in sexually abused patients with anismus. Fifteen women aged 41.2 +/- 4.1 years who had experienced sexual abuse in childhood (9 cases) or adulthood (6 cases) and complained of symptoms of irritable bowel disease were studied. Anismus was recorded during anorectal manometry in all cases. Patients were free to choose biofeedback and/or group psychotherapy and/or individual psychotherapy. When necessary, psychoactive drugs were prescribed after a psychiatric evaluation. Initially all the patients chose biofeedback and none accepted psychotherapy. Eight patients accepted psychotherapy after several weeks of biofeedback. Thirteen patients completed the study: 5 treated by biofeedback alone, 5 with biofeedback and group therapy, and 3 with biofeedback and individual psychotherapy. Eight women recovered completely from their symptoms, only two of whom had had biofeedback without psychotherapy. Biofeedback alone was not always sufficient to cure abused patients, but was chose initially by all the patients. It could initially be a middle path between somatic treatment and psychotherapy, at a time when patients are not yet ready to undertake the latter.

  20. The relaxation time approximation

    International Nuclear Information System (INIS)

    Gairola, R.P.; Indu, B.D.

    1991-01-01

    A plausible approximation has been made to estimate the relaxation time from a knowledge of the transition probability of phonons from one state (r vector, q vector) to other state (r' vector, q' vector), as a result of collision. The relaxation time, thus obtained, shows a strong dependence on temperature and weak dependence on the wave vector. In view of this dependence, relaxation time has been expressed in terms of a temperature Taylor's series in the first Brillouin zone. Consequently, a simple model for estimating the thermal conductivity is suggested. the calculations become much easier than the Callaway model. (author). 14 refs

  1. Biofeedback device for patients on axillary crutches.

    Science.gov (United States)

    Ang, E J; Goh, J C; Bose, K; Toh, S L; Choo, A

    1989-08-01

    The axillary crutch is commonly prescribed as an ambulatory aid to patients with temporal or permanent disability in the lower extremity. When fitting the axillary crutch, it is important that the user be instructed not to bear excessive weight on the axillary bar. Excessive weight bearing on the axillary bar can result in a sevenfold increase in the reaction force under the armpit. This force may be a contributory factor to crutch paralysis or thrombosis of the axillobrachial artery. In order to prevent this occurrence an electronic biofeedback device was designed and developed for use in the training of 3-point swing-through axillary crutch ambulation. It detects excessive weight bearing on the axillary bar during crutch ambulation and produces an audible signal which prompts the patient to make necessary adjustment to relieve load bearing on the axillary bar. The design and development of the biofeedback device is discussed in this paper.

  2. Thoracic ROM measurement system with visual bio-feedback: system design and biofeedback evaluation.

    Science.gov (United States)

    Ando, Takeshi; Kawamura, Kazuya; Fujitani, Junko; Koike, Tomokazu; Fujimoto, Masashi; Fujie, Masakatsu G

    2011-01-01

    Patients with diseases such as chronic obstructive pulmonary disease (COPD) need to improve their thorax mobility. Thoracic ROM is one of the simplest and most useful indexes to evaluate the respiratory function. In this paper, we have proposed the prototype of a simple thoracic ROM measurement system with real-time visual bio-feedback in the chest expansion test. In this system, the thoracic ROM is measured using a wire-type linear encoder whose wire is wrapped around the thorax. In this paper, firstly, the repeatability and reliability of measured thoracic ROM was confirmed as a first report of the developed prototype. Secondly, we analyzed the effect of the bio-feedback system on the respiratory function. The result of the experiment showed that it was easier to maintain a large and stable thoracic ROM during deep breathing by using the real-time visual biofeedback system of the thoracic ROM.

  3. The effect of biofeedback physical therapy in men with Chronic Pelvic Pain Syndrome Type III.

    Science.gov (United States)

    Cornel, Erik B; van Haarst, Ernst P; Schaarsberg, Ria W M Browning-Groote; Geels, Jenet

    2005-05-01

    Recent studies suggest that the symptoms of chronic non-bacterial prostatitis (CP) or Chronic Pelvic Pain Syndrome (CPPS) may be due to or associated with pelvic floor muscle dysfunction. Therapies aimed to improve relaxation and proper use of the pelvic floor muscles such as biofeedback physical therapy and pelvic floor re-education are expected to give symptom improvement. The objective of this study was to evaluate the effect of biofeedback physical therapy on the symptoms of men with CPPS. Between March 2000 to March 2004, 33 consecutive men were diagnosed with CP/CPPS based on history including the NIH-CPSI questionnaire and physical examination including pelvic floor muscle tonus, urinalysis, uroflowmetry with residual urine measurement and transrectal ultrasonography of the prostate. All patients participated in a pelvic floor biofeedback re-educating program. A rectal EMG probe was used to measure resting tone of the pelvic floor muscles and was helpful for instruction pelvic floor muscles contraction and relaxation. Two of the 33 men dropped out. In the remaining 31 men, mean age 43.9 years (range 23-70), the mean total Chronic Prostatitis Symptom Index (NIH-CPSI) changed from 23.6 (range 11-34) at baseline to 11.4 (range 1-25) after treatment (ppelvic floor muscle tonus was 4.9 at diagnosis (range 2.0-10.0) and decreased to 1.7 (range 0.5-2.8) after treatment (pphysical therapy and pelvic floor re-education for CP/CPPS patients, leading to a significant improvement of the symptom score. The correlation between the pelvic muscle tonus results with NIH-CPSI score is highly suggestive that the pelvic floor plays an important role in the pathophysiology of CP/CPPS.

  4. Thermally-induced electronic relaxation in structurally-modified Cu0.1Ni0.8Co0.2Mn1.9O4 spinel ceramics

    International Nuclear Information System (INIS)

    Shpotyuk, O.; Balitska, V.; Brunner, M.; Hadzaman, I.; Klym, H.

    2015-01-01

    Thermally-induced electronic relaxation in structurally-modified Cu 0.1 Ni 0.8 Co 0.2 Mn 1.9 O 4 spinel ceramics is shown to be adequately described by stretched exponential function on time. This kinetics is defined by microsctructure perfectness of the relaxing media, showing obvious onset to stretched exponential behaviour with non-exponentionality index attaining close to 0.43 values for high-monolith ceramics and smaller ones in fine-grained ceramics. Percolation threshold in relaxation-degradation kinetics is detected for ceramics with 10% of NiO extractions, showing the smallest but most prolonged single-path degradation effect. This finding is treated in terms of Phillips’ axiomatic diffusion-to-trap model, where only one of two relaxation channels (caused by operative short-range forces) occurs to be effective, while additional non-operative channels contribute to electronic relaxation in fine-grained ceramics

  5. Growth stress buildup in ion beam sputtered Mo thin films and comparative study of stress relaxation upon thermal annealing or ion irradiation

    International Nuclear Information System (INIS)

    Debelle, A.; Abadias, G.; Michel, A.; Jaouen, C.; Pelosin, V.

    2007-01-01

    In an effort to address the understanding of the origin of growth stress in thin films deposited under very energetic conditions, the authors investigated the stress state and microstructure of Mo thin films grown by ion beam sputtering (IBS) as well as the stress relaxation processes taking place during subsequent thermal annealing or ion irradiation. Different sets of samples were grown by varying the IBS deposition parameters, namely, the energy E 0 and the flux j of the primary ion beam, the target-to-sputtering gas mass ratio M 1 /M 2 as well as film thickness. The strain-stress state was determined by x-ray diffraction using the sin 2 ψ method and data analyzed using an original stress model which enabled them to correlate information at macroscopic (in terms of stress) and microscopic (in terms of defect concentration) levels. Results indicate that these refractory metallic thin films are characterized by a high compressive growth stress (-2.6 to -3.8 GPa), resulting from the creation of a large concentration (up to ∼1.4%) of point or cluster defects, due to the atomic peening mechanism. The M 1 /M 2 mass ratio enables tuning efficiently the mean deposited energy of the condensing atoms; thus, it appears to be the more relevant deposition parameter that allows modifying both the microstructure and the stress level in a significant way. The growth stress comes out to be highly unstable. It can be easily relaxed either by postgrowth thermal annealing or ion irradiation in the hundred keV range at very low dose [<0.1 dpa (displacement per atom)]. It is shown that thermal annealing induces deleterious effects such as oxidation of the film surface, decrease of the film density, and in some cases adhesion loss at the film/substrate interface, while ion irradiation allows controlling the stress level without generating any macroscopic damage

  6. A Cognitively Oriented Psychologist Looks at Bio-feedback

    Science.gov (United States)

    Lazarus, Richard S.

    1975-01-01

    It is advocated that bio-feedback research be approached within the larger context of emotion and adaption and oriented to the wide variety of mediators that affect the reaction pattern, rather than be treated as a special or unique kind of process limited to the bio-feedback laboratory. (EH)

  7. Biofeedback-Based, Videogame Balance Training in Autism

    Science.gov (United States)

    Travers, Brittany G.; Mason, Andrea H.; Mrotek, Leigh Ann; Ellertson, Anthony; Dean, Douglas C., III; Engel, Courtney; Gomez, Andres; Dadalko, Olga I.; McLaughlin, Kristine

    2018-01-01

    The present study examined the effects of a visual-based biofeedback training on improving balance challenges in autism spectrum disorder (ASD). Twenty-nine youth with ASD (7-17 years) completed an intensive 6-week biofeedback-based videogame balance training. Participants exhibited training-related balance improvements that significantly…

  8. The Reliability of Single Subject Statistics for Biofeedback Studies.

    Science.gov (United States)

    Bremner, Frederick J.; And Others

    To test the usefulness of single subject statistical designs for biofeedback, three experiments were conducted comparing biofeedback to meditation, and to a compound stimulus recognition task. In a statistical sense, this experimental design is best described as one experiment with two replications. The apparatus for each of the three experiments…

  9. An Introduction to Applications of Biofeedback Training in Counseling.

    Science.gov (United States)

    Danskin, David G.; Lowenstein, Timothy J.

    Biofeedback is the use of sensitive detectors (instruments) with visual and auditory displays to reveal to an individual minute changes in his internal physiological functions. Biofeedback training with such instruments results in the ability to voluntarily regulate physiological functions formerly believed involuntary. These physiological…

  10. Randomised controlled trial of biofeedback training in persistent encopresis with anismus.

    Science.gov (United States)

    Nolan, T; Catto-Smith, T; Coffey, C; Wells, J

    1998-08-01

    Paradoxical external anal sphincter contraction during attempted defecation (anismus) is thought to be an important contributor to chronic faecal retention and encopresis in children. Biofeedback training can be used to teach children to abolish this abnormal contraction. A randomised controlled trial in medical treatment resistant and/or treatment dependent children with anismus using surface electromyographic (EMG) biofeedback training to determine whether such training produces sustained faecal continence. Up to four sessions of biofeedback training were conducted at weekly intervals for each patient. Anorectal manometry was performed before randomisation and six months later. Parents of patients completed the "child behaviour checklist" (CBCL) before randomisation and at follow up. Sixty eight children underwent anorectal manometry and EMG. Of these, 29 had anismus (ages 4-14 years) and were randomised to either EMG biofeedback training and conventional medical treatment (BFT) (n = 14) or to conventional medical treatment alone (n = 15). All but one child were able to learn relaxation of the external anal sphincter on attempted defecation. At six months' follow up, laxative free remission had been sustained in two of 14 patients in the BFT group and in two of 15 controls (95% confidence interval (CI) on difference, -24% to 26%). Remission or improvement occurred in four of 14 patients in the BFT group and six of 15 controls (95% CI on difference, -46% to 23%). Of subjects available for repeat anorectal manometry and EMG at six months, six of 13 in the BFT group still demonstrated anismus v 11 of 13 controls (95% CI on difference, -75% to -1%). Of the four patients in full remission at six months, only one (in the BFT group) did not exhibit anismus. Rectal hyposensitivity was not associated with remission or improvement in either of the groups. Mean CBCL total behaviour problem scores were not significantly different between the BFT and control groups, but there

  11. Randomised controlled trial of biofeedback training in persistent encopresis with anismus

    Science.gov (United States)

    Nolan, T.; Catto-Smith, T.; Coffey, C.; Wells, J.

    1998-01-01

    BACKGROUND—Paradoxical external anal sphincter contraction during attempted defecation (anismus) is thought to be an important contributor to chronic faecal retention and encopresis in children. Biofeedback training can be used to teach children to abolish this abnormal contraction.
METHODS—A randomised controlled trial in medical treatment resistant and/or treatment dependent children with anismus using surface electromyographic (EMG) biofeedback training to determine whether such training produces sustained faecal continence. Up to four sessions of biofeedback training were conducted at weekly intervals for each patient. Anorectal manometry was performed before randomisation and six months later. Parents of patients completed the "child behaviour checklist" (CBCL) before randomisation and at follow up.
RESULTS—Sixty eight children underwent anorectal manometry and EMG. Of these, 29 had anismus (ages 4-14 years) and were randomised to either EMG biofeedback training and conventional medical treatment (BFT) (n = 14) or to conventional medical treatment alone (n = 15). All but one child were able to learn relaxation of the external anal sphincter on attempted defecation. At six months' follow up, laxative free remission had been sustained in two of 14 patients in the BFT group and in two of 15 controls (95% confidence interval (CI) on difference, −24% to 26%). Remission or improvement occurred in four of 14 patients in the BFT group and six of 15 controls (95% CI on difference, −46% to 23%). Of subjects available for repeat anorectal manometry and EMG at six months, six of 13 in the BFT group still demonstrated anismus v 11 of 13 controls (95% CI on difference, −75% to −1%). Of the four patients in full remission at six months, only one (in the BFT group) did not exhibit anismus. Rectal hyposensitivity was not associated with remission or improvement in either of the groups. Mean CBCL total behaviour problem scores were not significantly different

  12. Mechanical, relaxation behavior and thermal degradation of UV irradiated poly(vinyl acetate)/poly( methyl methacrylate) blends

    International Nuclear Information System (INIS)

    Mansour, S.A.; Hafez, M.; Hussien, K.A.

    2005-01-01

    The effect of different doses of UV- irradiation on the mechanical and relaxation properties of poly(vinyl acetate)/poly(methyl methacrylate) blends were studied. Films of PVAc/PMMA blend with different contents were prepared using the casting technique. Also, PMMA could be blended with PVAc to improve its impact strength. Moreover UV-irradiation causes degradation of PVAc and formation of ketonic and aldehyde carbonyl groups according to a suggested scheme. Irradiation of PvAc/ PMMA blends causes a higher degree of degradation as compared to the PVAc alone although the PMMA is more susceptible than PVAc to the influence of radiation. Recognizable differences are observed for all parameters between the unirradiated and irradiated samples. Existence of a relaxation mechanism within the first 200s is reported. The shear modulus for all samples is also obtained and discussed. These data are used to calculate the strain energy density using the equation proposed by Blatzetal(1974 trans. Soc.Rheol. 18 145-61), based on the n-measure of Sethe

  13. Structurally Oriented Nano-Sheets in Co Thin Films: Changing Their Anisotropic Physical Properties by Thermally-Induced Relaxation.

    Science.gov (United States)

    Vergara, José; Favieres, Cristina; Magén, César; de Teresa, José María; Ibarra, Manuel Ricardo; Madurga, Vicente

    2017-12-05

    We show how nanocrystalline Co films formed by separated oblique nano-sheets display anisotropy in their resistivity, magnetization process, surface nano-morphology and optical transmission. After performing a heat treatment at 270 °C, these anisotropies decrease. This loss has been monitored measuring the resistivity as a function of temperature. The resistivity measured parallel to the direction of the nano-sheets has been constant up to 270 °C, but it decreases when measured perpendicular to the nano-sheets. This suggests the existence of a structural relaxation, which produces the change of the Co nano-sheets during annealing. The changes in the nano-morphology and the local chemical composition of the films at the nanoscale after heating above 270 °C have been analysed by scanning transmission electron microscopy (STEM). Thus, an approach and coalescence of the nano-sheets have been directly visualized. The spectrum of activation energies of this structural relaxation has indicated that the coalescence of the nano-sheets has taken place between 1.2 and 1.7 eV. In addition, an increase in the size of the nano-crystals has occurred in the samples annealed at 400 °C. This study may be relevant for the application in devices working, for example, in the GHz range and to achieve the retention of the anisotropy of these films at higher temperatures.

  14. Structurally Oriented Nano-Sheets in Co Thin Films: Changing Their Anisotropic Physical Properties by Thermally-Induced Relaxation

    Directory of Open Access Journals (Sweden)

    José Vergara

    2017-12-01

    Full Text Available We show how nanocrystalline Co films formed by separated oblique nano-sheets display anisotropy in their resistivity, magnetization process, surface nano-morphology and optical transmission. After performing a heat treatment at 270 °C, these anisotropies decrease. This loss has been monitored measuring the resistivity as a function of temperature. The resistivity measured parallel to the direction of the nano-sheets has been constant up to 270 °C, but it decreases when measured perpendicular to the nano-sheets. This suggests the existence of a structural relaxation, which produces the change of the Co nano-sheets during annealing. The changes in the nano-morphology and the local chemical composition of the films at the nanoscale after heating above 270 °C have been analysed by scanning transmission electron microscopy (STEM. Thus, an approach and coalescence of the nano-sheets have been directly visualized. The spectrum of activation energies of this structural relaxation has indicated that the coalescence of the nano-sheets has taken place between 1.2 and 1.7 eV. In addition, an increase in the size of the nano-crystals has occurred in the samples annealed at 400 °C. This study may be relevant for the application in devices working, for example, in the GHz range and to achieve the retention of the anisotropy of these films at higher temperatures.

  15. The Effects of EEG Biofeedback Training on Hyperactive and/or Learning Disabled Children.

    Science.gov (United States)

    Kassel, Steve

    The literature review presents an explanation of biofeedback and a critical evaluation of the research pertaining to electroencephalographic (EEG) biofeedback training for the hyperactive and/or learning disabled child. Three hypotheses are examined: whether EEG biofeedback training is efficacious; whether EEG biofeedback training is more…

  16. The biofeedback treatment for non-monosymptomatic enuresis nocturna.

    Science.gov (United States)

    Ebiloglu, Turgay; Ergin, Giray; Irkilata, Hasan Cem; Kibar, Yusuf

    2016-01-01

    Enuresis is a child older than 5 years wetting in discrete portions during sleep. It has two subgroups: monosymptomatic enuresis nocturna (MSEN) and non-monosymptomatic enuresis nocturna (NMSEN). In this research, we specifically aimed to examine the effect of biofeedback in NMSEN. We retrospectively analyzed the hospital records of 182 children with NMSEN who were refractory to urotherapy modifications and directed to biofeedback therapies between 2005 and 2010. Enuresis before and after biofeedback therapies was evaluated. One or less enuretic night in a month was defined as success. There were 118 (64%) girls and 64 (35%) boys. With biofeedback therapy, 117 of 182 patients recovered with a success rate of 64% (P Biofeedback therapy is an effective treatment option for the enuresis component of NMSEN with a 64% success rate. © 2014 Wiley Periodicals, Inc.

  17. Studies on polymer electrolyte poly(vinyl) pyrrolidone (PVP) complexed with ionic liquid: Effect of complexation on thermal stability, conductivity and relaxation behaviour

    Energy Technology Data Exchange (ETDEWEB)

    Saroj, A.L. [Department of Physics, Banaras Hindu University, Varanasi, 221005 (India); Singh, R.K., E-mail: rksingh_17@rediffmail.com [Department of Physics, Banaras Hindu University, Varanasi, 221005 (India); Chandra, S. [Department of Physics, Banaras Hindu University, Varanasi, 221005 (India)

    2013-03-01

    Highlights: Black-Right-Pointing-Pointer PVP + IL based polymer electrolyte films have been prepared and studied. Black-Right-Pointing-Pointer The complexation/interaction of PVP with IL has been confirmed by FT-IR analysis. Black-Right-Pointing-Pointer The conductivity and relaxation frequency increases with increasing IL content. Black-Right-Pointing-Pointer Two relaxation peaks for complexed and uncomplexed PVP with IL have been observed. - Abstract: Polymer electrolyte films of PVP + x wt% ionic liquid (IL) (1-ethyl-3-methylimidazolium tetrafluoroborate [EMIM][BF{sub 4}]) for x = 0, 5, 10, 15, 20, 25 wt% have been prepared using solution cast technique. These films were characterized by TGA, DSC, FT-IR and ac impedance spectroscopy techniques. From XRD studies it is found that the inclusion of IL increases the amorphocity of polymeric membranes. DSC thermograms show that the glass transition (T{sub g}) and melting temperatures (T{sub m}) of PVP shift upon complexation with IL. FT-IR analysis shows the complexation of PVP with IL. Thermogravimetric studies show that PVP decomposes in a single step while PVP/IL membranes exhibit two step decomposition; lower value of decomposition temperature corresponds to the decomposition of PVP/IL complex while the higher decomposition temperature has been attributed to the decomposition of PVP. The decomposition temperature of PVP/IL complex decreases with the increasing amount of IL in the PVP membrane. Temperature dependence of conductivity and dielectric relaxation frequencies have also been studied for PVP and PVP/IL membranes. Both show thermally activated Arrhenius behaviour.

  18. X-ray diffraction analysis of thermally-induced stress relaxation in ZnO films deposited by magnetron sputtering on (100) Si substrates

    Energy Technology Data Exchange (ETDEWEB)

    Conchon, F., E-mail: florineconchon@gmail.co [Laboratoire de Physique des Materiaux (PHYMAT) UMR 6630, Universite de Poitiers, 86962 Futuroscope-Chasseneuil (France); Renault, P.O.; Goudeau, P.; Le Bourhis, E. [Laboratoire de Physique des Materiaux (PHYMAT) UMR 6630, Universite de Poitiers, 86962 Futuroscope-Chasseneuil (France); Sondergard, E.; Barthel, E.; Grachev, S. [Laboratoire de Surface du Verre et Interfaces (SVI), UMR 125, 93303 Aubervilliers (France); Gouardes, E.; Rondeau, V.; Gy, R. [Laboratoire de Recherche de Saint-Gobain (SGR), 93303 Aubervilliers (France); Lazzari, R.; Jupille, J. [Institut des Nanosciences de Paris (INSP), UMR 7588, 75015 Paris (France); Brun, N. [Laboratoire de Physique des Solides (LPS), UMR 8502, 91405 Orsay (France)

    2010-07-01

    Residual stresses in sputtered ZnO films on Si are determined and discussed. By means of X-ray diffraction, we show that as-deposited ZnO films are highly compressively stressed. Moreover, a transition of stress is observed as a function of the post-deposition annealing temperature. After an 800 {sup o}C annealing, ZnO films are tensily stressed while ZnO films encapsulated by Si{sub 3}N{sub 4} are stress-free. With the aid of in-situ X-ray diffraction under ambient and argon atmosphere, we argue that this thermally activated stress relaxation may be attributed to a variation of the stoichiometry of the ZnO films.

  19. A novel balance training system using multimodal biofeedback.

    Science.gov (United States)

    Afzal, Muhammad Raheel; Oh, Min-Kyun; Choi, Hye Young; Yoon, Jungwon

    2016-04-22

    A biofeedback-based balance training system can be used to provide the compromised sensory information to subjects in order to retrain their sensorimotor function. In this study, the design and evaluation of the low-cost, intuitive biofeedback system developed at Gyeongsang National University is extended to provide multimodal biofeedback for balance training by utilization of visual and haptic modalities. The system consists of a smartphone attached to the waist of the subject to provide information about tilt of the torso, a personal computer running a purpose built software to process the smartphone data and provide visual biofeedback to the subject by means of a dedicated monitor and a dedicated Phantom Omni(®) device for haptic biofeedback. For experimental verification of the system, eleven healthy young participants performed balance tasks assuming two distinct postures for 30 s each while acquiring torso tilt. The postures used were the one foot stance and the tandem Romberg stance. For both the postures, the subjects stood on a foam platform which provided a certain amount of ground instability. Post-experiment data analysis was performed using MATLAB(®) to analyze reduction in body sway. Analysis parameters based on the projection of trunk tilt information were calculated in order to ascertain the reduction in body sway and improvements in postural control. Two-way analysis of variance (ANOVA) showed no statistically significant interactions between postures and biofeedback. Post-hoc analysis revealed statistically significant reduction in body sway on provision of biofeedback. Subjects exhibited maximum body sway during no biofeedback trial, followed by either haptic or visual biofeedback and in most of the trials the multimodal biofeedback of visual and haptic together resulted in minimization of body sway, thus indicating that the multimodal biofeedback system worked well to provide significant (p biofeedback system can offer more customized training

  20. Smartphone Applications Utilizing Biofeedback Can Aid Stress Reduction

    Science.gov (United States)

    Dillon, Alison; Kelly, Mark; Robertson, Ian H.; Robertson, Deirdre A.

    2016-01-01

    Introduction: Stress is one of the leading global causes of disease and premature mortality. Despite this, interventions aimed at reducing stress have low adherence rates. The proliferation of mobile phone devices along with gaming-style applications allows for a unique opportunity to broaden the reach and appeal of stress-reduction interventions in modern society. We assessed the effectiveness of two smartphone applications games combined with biofeedback in reducing stress. Methods: We compared a control game to gaming-style smartphone applications combined with a skin conductance biofeedback device (the Pip). Fifty participants aged between 18 and 35 completed the Trier Social Stress Test. They were then randomly assigned to the intervention (biofeedback game) or control group (a non-biofeedback game) for thirty minutes. Perceived stress, heart rate and mood were measured before and after participants had played the games. Results: A mixed factorial ANOVA showed a significant interaction between time and game type in predicting perceived stress [F(1,48) = 14.19, p biofeedback intervention had significantly reduced stress compared to the control group. There was also a significant interaction between time and game in predicting heart rate [F(1,48) = 6.41, p biofeedback intervention showed significant reductions in heart rate compared to the control group. Discussion: This illustrates the potential for gaming-style smartphone applications combined with biofeedback as stress reduction interventions. PMID:27378963

  1. Biofeedback treatment for Tourette syndrome: a preliminary randomized controlled trial.

    Science.gov (United States)

    Nagai, Yoko; Cavanna, Andrea E; Critchley, Hugo D; Stern, Jeremy J; Robertson, Mary M; Joyce, Eileen M

    2014-03-01

    To study the clinical effectiveness of biofeedback treatment in reducing tics in patients with Tourette syndrome. Despite advances in the pharmacologic treatment of patients with Tourette syndrome, many remain troubled by their tics, which may be resistant to multiple medications at tolerable doses. Electrodermal biofeedback is a noninvasive biobehavioral intervention that can be useful in managing neuropsychiatric and neurologic conditions. We conducted a randomized controlled trial of electrodermal biofeedback training in 21 patients with Tourette syndrome. After training the patients for 3 sessions a week over 4 weeks, we observed a significant reduction in tic frequency and improved indices of subjective well-being in both the active-biofeedback and sham-feedback (control) groups, but there was no difference between the groups in these measurements. Furthermore, the active-treatment group did not demonstrably learn to reduce their sympathetic electrodermal tone using biofeedback. Our findings indicate that this form of biofeedback training was unable to produce a clinical effect greater than placebo. The main confounding factor appeared to be the 30-minute duration of the training sessions, which made it difficult for patients to sustain a reduction in sympathetic tone when their tics themselves were generating competing phasic electrodermal arousal responses. Despite a negative finding in this study, electrodermal biofeedback training may have a role in managing tics if optimal training schedules can be identified.

  2. Heart rate variability biofeedback improves cardiorespiratory resting function during sleep.

    Science.gov (United States)

    Sakakibara, Masahito; Hayano, Junichiro; Oikawa, Leo O; Katsamanis, Maria; Lehrer, Paul

    2013-12-01

    The present study was designed to examine the effect of heart rate variability (HRV) biofeedback on the cardiorespiratory resting function during sleep in daily life. Forty-five healthy young adults were randomly assigned to one of three groups: HRV biofeedback, Autogenic Training(AT), and no-treatment control. Participants in the HRV biofeedback were instructed to use a handheld HRV biofeedback device before their habitual bedtime, those in the AT were asked to listen to an audiotaped instruction before bedtime,and those in the control were asked to engage in their habitual activity before bedtime. Pulse wave signal during sleep at their own residences was measured continuously with a wrist watch-type transdermal photoelectric sensor for three time points. Baseline data were collected on the first night of measurements, followed by two successive nights for HRV biofeedback, AT, or control. Cardiorespiratory resting function was assessed quantitatively as the amplitude of high frequency(HF) component of pulse rate variability, a surrogate measure of respiratory sinus arrhythmia. HF component increased during sleep in the HRV biofeedback group,although it remained unchanged in the AT and control groups. These results suggest that HRV biofeedback before sleep may improve cardiorespiratory resting function during sleep.

  3. Presence and biofeedback in first-person perspective computer games

    DEFF Research Database (Denmark)

    Grimshaw-Aagaard, Mark Nicholas

    2019-01-01

    . Following the line taken by presence theorists, I differentiate between immersion, an objective measure such that computer game technology can be less or more immersive, and presence, a subjective, human response to that technology. The third section looks at current possibilities for biofeedback...... in relation to sound design for first-person perspective computer games; in line with the first section, biofeedback devices are treated as an immersive technology. I close the chapter by suggesting ways in which sound design in such games might make use of biofeedback to enhance the perception of presence...

  4. Audiovisual biofeedback improves diaphragm motion reproducibility in MRI

    Science.gov (United States)

    Kim, Taeho; Pollock, Sean; Lee, Danny; O’Brien, Ricky; Keall, Paul

    2012-01-01

    Purpose: In lung radiotherapy, variations in cycle-to-cycle breathing results in four-dimensional computed tomography imaging artifacts, leading to inaccurate beam coverage and tumor targeting. In previous studies, the effect of audiovisual (AV) biofeedback on the external respiratory signal reproducibility has been investigated but the internal anatomy motion has not been fully studied. The aim of this study is to test the hypothesis that AV biofeedback improves diaphragm motion reproducibility of internal anatomy using magnetic resonance imaging (MRI). Methods: To test the hypothesis 15 healthy human subjects were enrolled in an ethics-approved AV biofeedback study consisting of two imaging sessions spaced ∼1 week apart. Within each session MR images were acquired under free breathing and AV biofeedback conditions. The respiratory signal to the AV biofeedback system utilized optical monitoring of an external marker placed on the abdomen. Synchronously, serial thoracic 2D MR images were obtained to measure the diaphragm motion using a fast gradient-recalled-echo MR pulse sequence in both coronal and sagittal planes. The improvement in the diaphragm motion reproducibility using the AV biofeedback system was quantified by comparing cycle-to-cycle variability in displacement, respiratory period, and baseline drift. Additionally, the variation in improvement between the two sessions was also quantified. Results: The average root mean square error (RMSE) of diaphragm cycle-to-cycle displacement was reduced from 2.6 mm with free breathing to 1.6 mm (38% reduction) with the implementation of AV biofeedback (p-value biofeedback (p-value biofeedback (p-value = 0.012). The diaphragm motion reproducibility improvements with AV biofeedback were consistent with the abdominal motion reproducibility that was observed from the external marker motion variation. Conclusions: This study was the first to investigate the potential of AV biofeedback to improve the motion

  5. Biofeedback monitoring-devices for astronauts in space environment

    Science.gov (United States)

    Rotondo, G.; Pancheri, P.; Monesi, F.; Grantaliano, G.; DePascalis, V.

    After a reconsideration of the state-of-the-art in biofeedback research the implementation of biofeedback systems is envisioned as a countermeasure of stress for the psychoprophylaxis of the astronaut. A one-session experiment performed on two groups of subjects to assess the interference from EMG-feedback on the performance in a simultaneous psychomotor trial with a view to expanding biofeedback application is described. The results show that the experimental group performed in the same way as the control without feedback, but with less CNS activation. Some general conclusions are drawn from the advances in technology.

  6. Nonstoichiometric control of tunnel-filling order, thermal expansion, and dielectric relaxation in tetragonal tungsten Bronzes Ba0.5-xTaO3-x.

    Science.gov (United States)

    Pan, Fengjuan; Li, Xiaohui; Lu, Fengqi; Wang, Xiaoming; Cao, Jiang; Kuang, Xiaojun; Véron, Emmanuel; Porcher, Florence; Suchomel, Matthew R; Wang, Jing; Allix, Mathieu

    2015-09-21

    Ordering of interpolated Ba(2+) chains and alternate Ta-O rows (TaO)(3+) in the pentagonal tunnels of tetragonal tungsten bronzes (TTB) is controlled by the nonstoichiometry in the highly nonstoichiometric Ba0.5-xTaO3-x system. In Ba0.22TaO2.72, the filling of Ba(2+) and (TaO)(3+) groups is partially ordered along the ab-plane of the simple TTB structure, resulting in a √2-type TTB superstructure (Pbmm), while in Ba0.175TaO2.675, the pentagonal tunnel filling is completely ordered along the b-axis of the simple TTB structure, leading to a triple TTB superstructure (P21212). Both superstructures show completely empty square tunnels favoring Ba(2+) conduction and feature unusual accommodation of Ta(5+) cations in the small triangular tunnels. In contrast with stoichiometric Ba6GaTa9O30, which shows linear thermal expansion of the cell parameters and monotonic decrease of permittivity with temperature within 100-800 K, these TTB superstructures and slightly nonstoichiometric simple TTB Ba0.4TaO2.9 display abnormally broad and frequency-dependent extrinsic dielectric relaxations in 10(3)-10(5) Hz above room temperature, a linear deviation of the c-axis thermal expansion around 600 K, and high dielectric permittivity ∼60-95 at 1 MHz at room temperature.

  7. Thermal- and pH-Dependent Size Variable Radical Nanoparticles and Its Water Proton Relaxivity for Metal-Free MRI Functional Contrast Agents.

    Science.gov (United States)

    Morishita, Kosuke; Murayama, Shuhei; Araki, Takeru; Aoki, Ichio; Karasawa, Satoru

    2016-09-16

    For development of the metal-free MRI contrast agents, we prepared the supra-molecular organic radical, TEMPO-UBD, carrying TEMPO radical, as well as the urea, alkyl group, and phenyl ring, which demonstrate self-assembly behaviors using noncovalent bonds in an aqueous solution. In addition, TEMPO-UBD has the tertiary amine and the oligoethylene glycol chains (OEGs) for the function of pH and thermal responsiveness. By dynamic light scattering and transmission electron microscopy imaging, the resulting self-assembly was seen to form the spherical nanoparticles 10-150 nm in size. On heating, interestingly, the nanoparticles showed a lower critical solution temperature (LCST) behavior having two-step variation. This double-LCST behavior is the first such example among the supra-molecules. To evaluate of the ability as MRI contrast agents, the values of proton ((1)H) longitudinal relaxivity (r1) were determined using MRI apparatus. In conditions below and above CAC at pH 7.0, the distinguishable r1 values were estimated to be 0.17 and 0.21 mM(-1) s(1), indicating the suppression of fast tumbling motion of TEMPO moiety in a nanoparticle. Furthermore, r1 values became larger in the order of pH 7.0 > 9.0 > 5.0. Those thermal and pH dependencies indicated the possibility of metal-fee MRI functional contrast agents in the future.

  8. Relaxation Techniques for Health

    Science.gov (United States)

    ... and biofeedback in the management of temporomandibular disorder . Physical Therapy . 2006;86(7):955–973. Morin CM, Bootzin ... treatments for late-life anxiety . American Journal of Geriatric ... therapy for rehabilitation and prevention in ischaemic heart disease: ...

  9. IS A COGNITIVE-BEHAVIOURAL BIOFEEDBACK INTERVENTION USEFUL TO REDUCE INJURY RISK IN JUNIOR FOOTBALL PLAYERS?

    Directory of Open Access Journals (Sweden)

    Arne Edvardsson

    2012-06-01

    Full Text Available Athletes participating in sport are exposed to a relatively high injury risk. Previous research has suggested that it could be possible to reduce sports injuries through psychological skills training. The purpose of this study was to examine the extent to which a cognitive behavioural biofeedback intervention could reduce the number of sports injuries in a sample of players in Swedish elite football high schools. Participants from four elite football high schools (16-19 years old were divided into one experiment (n = 13 and one control group (n = 14. Participants were asked to complete three questionnaires to assess anxiety level (Sport Anxiety Scale, history of stressors (Life Event Scale for Collegiate Athletes and coping skills (Athletic Coping Skills Inventory - 28 in a baseline measure. Mann-Whitney U-tests showed no significant differences in pre-intervention scores based on the questionnaires. The experimental group participated in a nine-week intervention period consisting of seven sessions, including: somatic relaxation, thought stopping, emotions/problem focused coping, goal setting, biofeedback training as well as keeping a critical incident diary. A Mann-Whitney U test showed no significant difference between the control and experimental group U (n1 = 13, n2 = 14 = 51.00, p = 0.054. However, considering the small sample, the statistical power (0.05 for present study, to detect effects was low. The results of the study are discussed from a psychological perspective and proposals for future research are given

  10. Simultaneous EEG and EMG biofeedback for peak performance in musicians.

    Science.gov (United States)

    Markovska-Simoska, Silvana; Pop-Jordanova, Nada; Georgiev, Dejan

    2008-07-01

    The aim of this study was to determine the effects of alpha neurofeedback and EMG biofeedback protocols for improvement of musical performance in violinists. The sample consisted of 12 music students (10 violinists and 2 viola players) from the Faculty of Music, Skopje (3 males, mean age of 20 +/- 0 and 9 females, mean age = 20.89 +/- 2.98). Six of them had a low alpha peak frequency (APF) ( 10 Hz). The sample was randomized in two groups. The students from the experimental group participated in 20 sessions of biofeedback (alpha/EMG), combined with music practice, while the students from the control group did only music practice. Average absolute power, interhemispheric coherence in the alpha band, alpha peak frequency (APF), individual alpha band width (IABW), amount of alpha suppression (AAS) and surface forehead integrated EMG power (IEMG), as well as a score on musical performance and inventories measuring anxiety, were assessed. Alpha-EEG/EMG-biofeedback was associated with a significant increase in average alpha power, APF and IABW in all the participants and with decreases in IEMG only in high-APF musicians. The biofeedback training success was positively correlated with the alpha power, IcoH, APF, IABW and baseline level of APF and IABW. Alpha-EEG/EMG biofeedback is capable of increasing voluntary self-regulation and the quality of musical performance. The efficiency of biofeedback training depends on the baseline EEG alpha activity status, in particular the APF.

  11. Biofeedback for pain management in traumatised refugees.

    Science.gov (United States)

    Muller, Julia; Karl, Anke; Denke, Claudia; Mathier, Fabienne; Dittmann, Jennifer; Rohleder, Nicolas; Knaevelsrud, Christine

    2009-01-01

    Chronic pain (CP) and posttraumatic stress disorder (PTSD) are both frequent and often comorbid in refugees. To date, few controlled trials have studied the efficacy of treatments targeting this comorbidity; no treatment guidelines yet exist. The authors examined the feasibility and efficacy of short-term cognitive behavioural biofeedback (BF) addressing CP in traumatised refugees. The sample comprised 11 severely traumatised refugees with CP and PTSD (mean age = 36 years, SD = 6), who underwent assessment with the Mini International Neuropsychiatric Interview, Posttraumatic Diagnostic Scale, Pain Disability Index, and Visual Rating Scale. Additionally, coping with pain and psychotherapy tolerance were assessed. Acceptance of BF was high. Pre-post effects were small to medium for increased pain management and associated heart rate reactivity but large for coping with pain. The results encourage further research to confirm whether BF is indicated as a treatment component, but not a stand-alone treatment, for traumatised refugees with comorbid CP and PTSD.

  12. Relaxation System

    Science.gov (United States)

    1987-01-01

    Environ Corporation's relaxation system is built around a body lounge, a kind of super easy chair that incorporates sensory devices. Computer controlled enclosure provides filtered ionized air to create a feeling of invigoration, enhanced by mood changing aromas. Occupant is also surrounded by multidimensional audio and the lighting is programmed to change colors, patterns, and intensity periodically. These and other sensory stimulators are designed to provide an environment in which the learning process is stimulated, because research has proven that while an individual is in a deep state of relaxation, the mind is more receptive to new information.

  13. Psycho-echo-biofeedback: a novel treatment for anismus--results of a prospective controlled study.

    Science.gov (United States)

    Del Popolo, F; Cioli, V M; Plevi, T; Pescatori, M

    2014-10-01

    Anismus or non-relaxing puborectalis muscle (PRM), detectable with anal/vaginal ultrasound (US), is a cause of obstructed defecation (OD) and may be treated with biofeedback (BFB). Many patients with anismus are anxious and/or depressed. The aim of this prospective study was to evaluate the outcome of the novel procedure psycho-echo-BFB in patients with anismus and psychological disorders. Patients presenting at our unit with anismus and psychological disorders between January 2009 and December 2013, and not responding to conventional conservative treatment, were enrolled in the study. All underwent four sessions of psycho-echo-BFB, carried out by two psychologists and a coloproctologist, consisting of guided imagery, relaxation techniques and anal/vaginal US-assisted BFB. A validated score for OD was used, and PRM relaxation on straining measured before and after the treatment. PRM relaxation was also measured in a control group of 7 patients with normal bowel habits. Ten patients (8 females, median age 47 years, range 26-72 years) underwent psycho-echo-BFB. The OD score, evaluated prior to and at a median of 25 months (range 1-52 months) after the treatment, improved in 7 out of 10 patients, from 13.5 ± 1.2 to 9.6 ± 2.2 (mean ± standard error of the mean (SEM)), p = 0.06. At the end of the last session, PRM relaxed on straining in all cases, from 0 to 7.1 ± 1.1 mm, i.e., physiological values, not statistically different from those of controls (6.6 ± 1.5 mm). Two patients reported were cured, 3 improved and 5, all of whom had undergone prior anorectal surgery, unchanged. No side effects were reported. Psycho-echo-BFB is safe and inexpensive and allows all patients with anismus to relax PRM on straining. Previous anorectal surgery may be a negative predictor.

  14. Structural relaxation and thermal conductivity of high-pressure formed, high-density di-n-butyl phthalate glass and pressure induced departures from equilibrium state.

    Science.gov (United States)

    Johari, G P; Andersson, Ove

    2017-06-21

    We report a study of structural relaxation of high-density glasses of di-n-butyl phthalate (DBP) by measuring thermal conductivity, κ, under conditions of pressure and temperature (p,T) designed to modify both the vibrational and configurational states of a glass. Various high-density glassy states of DBP were formed by (i) cooling the liquid under a fixed high p and partially depressurizing the glass, (ii) isothermal annealing of the depressurized glass, and (iii) pressurizing the glass formed by cooling the liquid under low p. At a given low p, κ of the glass formed by cooling under high p is higher than that of the glass formed by cooling under low p, and the difference increases as glass formation p is increased. κ of the glass formed under 1 GPa is ∼20% higher at ambient p than κ of the glass formed at ambient p. On heating at low p, κ decreases until the glass to liquid transition range is reached. This is the opposite of the increase in κ observed when a glass formed under a certain p is heated under the same p. At a given high p, κ of the low-density glass formed by cooling at low p is lower than that of the high-density glass formed by cooling at that high p. On heating at high p, κ increases until the glass to liquid transition range is reached. The effects observed are due to a thermally assisted approach toward equilibrium at p different from the glass formation p. In all cases, the density, enthalpy, and entropy would change until the glasses become metastable liquids at a fixed p, thus qualitatively relating κ to variation in these properties.

  15. Comparative study between biofeedback retraining and botulinum neurotoxin in the treatment of anismus patients.

    Science.gov (United States)

    Farid, Mohamed; El Monem, Hisham Abd; Omar, Waleed; El Nakeeb, Ayman; Fikry, Amir; Youssef, Tamer; Yousef, Mohamed; Ghazy, Hosam; Fouda, Elyamani; El Metwally, Teto; Khafagy, Wael; Ahmed, Sabry; El Awady, Salih; Morshed, Mosaad; El Lithy, Ramadan

    2009-01-01

    Anismus is a significant cause of chronic constipation. This study came to revive the results of BFB training and BTX-A injection in the treatment of anismus patients. Forty-eight patients with anismus (33 women; mean age 39.6 +/- 15.9) were included in this study. All patients fulfilled Rome II criteria for functional constipation. All patients underwent anorectal manometry, balloon expulsion test, defecography, and electromyography (EMG) activity of the EAS. All patients had non-relaxing puborectalis muscle. The patients were randomized into two groups. Group I patients received biofeedback therapy, two times per week for about 1 month. Group II patients were injected with BTX-A. Follow-up was conducted weekly in the first month then monthly for about 1 year. In the BFB training group, three patients quit before the end of sessions with no improvement; initial improvement was recorded in 12 patients (50%) while long-term success was recorded in six patients (25%). In the BTX-A group, clinical improvement was recorded in 17 patients (70.83%), but the improvement persisted only in eight patients (33.3%). There is a significant difference between BTX-A group and BFB group regarding the initial success, but this significant difference disappeared at the end of follow-up. Manometric relaxation was achieved significantly post-BFB and post-BTX-A injection with no significant difference between the two groups. Biofeedback training has a limited therapeutic effect on patients suffering from anismus. BTX-A injection seems to be successful for temporary treatment of anismus.

  16. Differential Biofeedback Intervention in Moderating Inhibited Performance in Soccer

    Directory of Open Access Journals (Sweden)

    Soumendra Saha

    2016-01-01

    Full Text Available Performance excellence in soccer crucially depends on mental toughness or more specifically the aspect of emotional flexibility and hardiness of the player. Since indices of projective evaluations can reveal hidden emotional crises and internal conflicts, psychobiological evaluations could substantiate with the inner emotionality revealed to provide etiological information related to performance hindrances in soccer. Present study was carried out to identify the efficacy of skin conductance (Sc biofeedback in regulation of sudomotor nerve activity (SNA and of electromyography (EMG biofeedback in regulation of peak torque and maximal voluntary contraction (MVC in modification of performance catastrophe in soccer. All of them were assessed with autonomic measures (SNA and Sc amplitude; electromyography evaluation of emotionality and MVC revealed through EMG. Forty National-selection group soccer players of Malaysia were randomly categorized into four groups (Gr. A, N = 10, no-intervention control group; Gr. B (who received Sc biofeedback training; Gr. C (received EMG biofeedback intervention and Gr. D (players who received combined training of Sc and EMG biofeedback intervention. Players of intervention groups received their respective trainings for 12 weeks (15 min.s /day for 3 days/ week. Post-intervention analyses revealed marked improvement in the soccer players who received Sc and EMG biofeedback intervention, and the combined biofeedback training was evident as most efficient intervention technique in modulating emotionality as well as muscle potentiality. Analysis of variance and repeated measure of ANOVA were done to observe shared aetiology in the form of direct, inverse and supportive relationships between psychobiological and emotional indices related to performance crises in soccer. Comprehensive understanding of the confounding relationships between subjective feelings emotionality and corroborative psychobiological indices as

  17. Biofeedback for anismus: has placebo effect been overlooked?

    Science.gov (United States)

    Meagher; Sun; Kennedy; Smart; Lubowski

    1999-03-01

    Multiple uncontrolled studies have concluded that biofeedback is successful in treating anismus. This study's objective was to assess the physiological effects of placebo and biofeedback treatment on patients with anismus and to correlate changes with clinical improvement. Twelve patients with symptoms and electrophysiological findings of anismus were studied. Initial assessment included a detailed history, symptom assessment by linear analogue scales, anorectal manometric and electrophysiological studies, colon transit scintigraphy, and scintigraphic proctography. Patients underwent 5 days of placebo treatment, followed 1 week later by re-assessment of symptoms and physiological studies. Five days of biofeedback was then given followed by another complete re-assessment 1 week later. A final interview was performed 2 months later. All assessments were by an independent observer who was not responsible for the treatments. Seven patients reported an overall improvement in symptoms following placebo treatment. A total of seven patients reported improvement following biofeedback, three of whom had already reported an improvement with placebo. One patient who reported improvement following placebo had worsening of symptoms following biofeedback. The only symptoms or tests which changed more with biofeedback than placebo were anal pressure and electromyographic activity on attempted defaecation in the left lateral position. There was no demonstrable correlation between change in symptoms and change in physiological tests. The scintigraphic 'ejection fraction' of the rectum was unchanged by treatment. Clinical improvement in previous studies may in part be due to placebo effect and observer bias. Improvement with biofeedback may be due to physiological changes which are not detected with conventional anorectal physiological tests.

  18. The Improvement of Dental Posture Using Personalized Biofeedback.

    Science.gov (United States)

    Thanathornwong, Bhornsawan; Suebnukarn, Siriwan

    2015-01-01

    Dentists are subject to staying in static or awkward postures for long periods due to their highly concentrated work. This study describes a real-time personalized biofeedback system developed for dental posture training with the use of vibrotactile biofeedback. The real-time personalized biofeedback system was an integrated solution that comprised of two components: 1) a wearable device that contained an accelerometer sensor for measuring the tilt angle of the body (input) and provided real-time vibrotactile biofeedback (output); and 2) software for data capturing, processing, and personalized biofeedback generation. The implementation of real-time personalized vibrotactile feedback was computed using Hidden Markov Models (HMMs). For the test case, we calculated the probability and log-likelihood of the test movements under the Work related Musculoskeletal Disorders (WMSD) and non-WMSD HMMs. The vibrotactile biofeedback was provided to the user via a wearable device for a WMSD-predicted case. In the system evaluation, a randomized crossover trial was conducted to compare dental posture measure using tilt angles of the upper back and muscle activities of those dental students that received vibrotactile biofeedback from the system with the control group against the dental students who received no feedback. The participants who received feedback from the system had a lower tilt angle at 10th, 50th, and 90th percentiles of Backx and Backy, as well as muscular load, which were statistically different (pbiofeedback system for posture training in dental students is feasible and associated with quantitative improvements of the dental posture.

  19. Thermally-induced electronic relaxation in structurally-modified Cu{sub 0.1}Ni{sub 0.8}Co{sub 0.2}Mn{sub 1.9}O{sub 4} spinel ceramics

    Energy Technology Data Exchange (ETDEWEB)

    Shpotyuk, O., E-mail: shpotyuk@novas.lviv.ua [Institute of Materials, Scientific Research Company “Carat”, 202, Stryjska Street, Lviv 79031 (Ukraine); Institute of Physics, Jan Dlugosz University, 13/15, al. Armii Krajowej, Czestochowa 42200 Poland (Poland); Balitska, V. [Institute of Materials, Scientific Research Company “Carat”, 202, Stryjska Street, Lviv 79031 (Ukraine); Lviv State University of Vital Activity Safety, 35, Kleparivska Street, Lviv 79007 (Ukraine); Brunner, M. [Fachhochschule Köln/University of Applied Sciences, 2, Betzdorfer Strasse, Köln 50679 (Germany); Hadzaman, I. [Institute of Materials, Scientific Research Company “Carat”, 202, Stryjska Street, Lviv 79031 (Ukraine); Drohobych Ivan Franko State Pedagogical University, 24, I. Franko Street, Drohobych 82100 (Ukraine); Klym, H. [Institute of Materials, Scientific Research Company “Carat”, 202, Stryjska Street, Lviv 79031 (Ukraine); Lviv Polytechnic National University, 12, Bandera Street, Lviv 79013 (Ukraine)

    2015-02-15

    Thermally-induced electronic relaxation in structurally-modified Cu{sub 0.1}Ni{sub 0.8}Co{sub 0.2}Mn{sub 1.9}O{sub 4} spinel ceramics is shown to be adequately described by stretched exponential function on time. This kinetics is defined by microsctructure perfectness of the relaxing media, showing obvious onset to stretched exponential behaviour with non-exponentionality index attaining close to 0.43 values for high-monolith ceramics and smaller ones in fine-grained ceramics. Percolation threshold in relaxation-degradation kinetics is detected for ceramics with 10% of NiO extractions, showing the smallest but most prolonged single-path degradation effect. This finding is treated in terms of Phillips’ axiomatic diffusion-to-trap model, where only one of two relaxation channels (caused by operative short-range forces) occurs to be effective, while additional non-operative channels contribute to electronic relaxation in fine-grained ceramics.

  20. Exploring the role of self-efficacy in biofeedback video games

    NARCIS (Netherlands)

    Weerdmeester, J.W.; Rooij, M.M.J.W. van; Harris, O.; Smit, N.; Engels, R.C.M.E.; Granic, I.

    2017-01-01

    Biofeedback training and game-based biofeedback are increasingly used to improve mental health. When evaluating the effects of biofeedback however, the focus often lies solely on therapeutic outcomes. Meanwhile, it is known that psychological factors such as perceptions of competence, also known as

  1. Direction of attentional focus in biofeedback treatment for /r/ misarticulation.

    Science.gov (United States)

    McAllister Byun, Tara; Swartz, Michelle T; Halpin, Peter F; Szeredi, Daniel; Maas, Edwin

    2016-07-01

    Maintaining an external direction of focus during practice is reported to facilitate acquisition of non-speech motor skills, but it is not known whether these findings also apply to treatment for speech errors. This question has particular relevance for treatment incorporating visual biofeedback, where clinician cueing can direct the learner's attention either internally (i.e., to the movements of the articulators) or externally (i.e., to the visual biofeedback display). This study addressed two objectives. First, it aimed to use single-subject experimental methods to collect additional evidence regarding the efficacy of visual-acoustic biofeedback treatment for children with /r/ misarticulation. Second, it compared the efficacy of this biofeedback intervention under two cueing conditions. In the external focus (EF) condition, participants' attention was directed exclusively to the external biofeedback display. In the internal focus (IF) condition, participants viewed a biofeedback display, but they also received articulatory cues encouraging an internal direction of attentional focus. Nine school-aged children were pseudo-randomly assigned to receive either IF or EF cues during 8 weeks of visual-acoustic biofeedback intervention. Accuracy in /r/ production at the word level was probed in three to five pre-treatment baseline sessions and in three post-treatment maintenance sessions. Outcomes were assessed using visual inspection and calculation of effect sizes for individual treatment trajectories. In addition, a mixed logistic model was used to examine across-subjects effects including phase (pre/post-treatment), /r/ variant (treated/untreated), and focus cue condition (internal/external). Six out of nine participants showed sustained improvement on at least one treated /r/ variant; these six participants were evenly divided across EF and IF treatment groups. Regression results indicated that /r/ productions were significantly more likely to be rated accurate post

  2. Biofeedback and neurofeedback application in the treatment of migraine.

    Science.gov (United States)

    Martic-Biocina, Sanja; Zivoder, Ivana; Kozina, Goran

    2017-09-01

    Biofeedback is a non-invasive method of measurement of physiological functions. Precise instruments measure the slightest changes of different body functions-which are then in a clear and understandable manner shown in the form of feedback. Person gets an insight into what is going on inside the body and thus learns to change the patterns of behavior to improve health and performance. Any changes that are wanted are rewarded, which leads to learning of the new patterns of behavior. Neurofeedback is a type of biofeedback which uses electrical activity in the brain. Certain disorders are associated with specific patterns of brain activity, and through neurofeedback it is possible to reduce or even remove symptoms of some disorders. In the treatment of migraine different biofeedback methods- such as breathing, training of vasoconstriction/vasodilatation and neurofeedback, may be applied. This paper will describe the successful treatment of 25 years old girl who suffered for many years from painful migraine. She had in total 25 treatments during which listed biofeedback methods were used. The first part of the treatment was neurofeedback training on the central sensorimotor area, followed by respiration training and at the end by biofeedback training of vasoconstriction/vasodilatation. The final result of the treatment was significant reduce in the frequency of migraine attacks and the pain reduction. Further study, have to be done with more patients and with placebo group to scientifically prove the effectiveness of the method.

  3. Biofeedback as Prophylaxis for Pediatric Migraine: A Meta-analysis.

    Science.gov (United States)

    Stubberud, Anker; Varkey, Emma; McCrory, Douglas C; Pedersen, Sindre Andre; Linde, Mattias

    2016-08-01

    Migraine is a common problem in children and adolescents, but few satisfactory prophylactic treatments exist. Our goal was to investigate the pooled evidence for the effectiveness of using biofeedback to reduce childhood migraine. A systematic search was conducted across the databases Medline, Embase, CENTRAL, CINAHL, and PsychINFO. Prospective, randomized controlled trials of biofeedback for migraine among children and adolescents were located in the search. Data on reduction of mean attack frequency and a series of secondary outcomes, including adverse events, were extracted. Risk of bias was also assessed. Forest plots were created by using a fixed effects model, and mean differences were reported. Five studies with a total of 137 participants met the inclusion criteria. Biofeedback reduced migraine frequency (mean difference, -1.97 [95% confidence interval (CI), -2.72 to -1.21]; P Biofeedback demonstrated no adjuvant effect when combined with other behavioral treatment; neither did it have significant advantages over active treatment. Only 40% of bias judgments were deemed as "low" risk. Methodologic issues hampered the meta-analyses. Only a few studies were possible to include, and they suffered from incomplete reporting of data and risk of bias. Biofeedback seems to be an effective intervention for pediatric migraine, but in light of the limitations, further investigation is needed to increase our confidence in the estimate. Copyright © 2016 by the American Academy of Pediatrics.

  4. Biofeedback treatment for sleep bruxism: a systematic review.

    Science.gov (United States)

    Wang, Lu-Fei; Long, Hu; Deng, Meng; Xu, Hui; Fang, Jie; Fan, Yi; Bai, Ding; Han, Xiang-Long

    2014-05-01

    The aim of this systematic review was to evaluate the efficacy of any biofeedback treatment on sleep bruxism. We searched the Cochrane Central Register of Controlled Trials, MEDLINE, Embase, ISI Web of Science, System for Information on Grey Literature in Europe, Chinese Biomedical Literature Database, and PsycINFO up to October 2012 for randomized controlled trials and controlled clinical trials involving biofeedback treatment for sleep bruxism. Reference lists of relevant studies were hand searched. Quality assessment and data extraction were performed by two reviewers independently. Seven eligible studies involving 240 participants were finally included. Three of them had moderate risk of bias, and four had high risk of bias. In an electromyographic-measured sleep bruxism episode, meta-analysis showed no significant difference between contingent electrical stimulation and blank control (95% confidence interval = -12.33, 3.38, P = 0.26). Moreover, five studies reported electromyographic activity index. Due to the diversity of biofeedback modalities (auditory, electrical, and visual stimulus) and controls (splint, occlusal adjustment, etc.), these data were unable to be pooled, so only qualitative description was provided. In the current stage, there is no powerful evidence to support the use of biofeedback technology on sleep bruxism treatment. Contingent electrical stimulation which is defined as a kind of biofeedback modality shows no effect on reducing sleep bruxism episode compared with the no-treatment group. Although many studies support the efficacy of biofeedback treatment, more large sample-sized randomized controlled trials which adopt uniform outcome index are necessitated to verify its application.

  5. A mathematical model for incorporating biofeedback into human postural control

    Directory of Open Access Journals (Sweden)

    Ersal Tulga

    2013-02-01

    Full Text Available Abstract Background Biofeedback of body motion can serve as a balance aid and rehabilitation tool. To date, mathematical models considering the integration of biofeedback into postural control have represented this integration as a sensory addition and limited their application to a single degree-of-freedom representation of the body. This study has two objectives: 1 to develop a scalable method for incorporating biofeedback into postural control that is independent of the model’s degrees of freedom, how it handles sensory integration, and the modeling of its postural controller; and 2 to validate this new model using multidirectional perturbation experimental results. Methods Biofeedback was modeled as an additional torque to the postural controller torque. For validation, this biofeedback modeling approach was applied to a vibrotactile biofeedback device and incorporated into a two-link multibody model with full-state-feedback control that represents the dynamics of bipedal stance. Average response trajectories of body sway and center of pressure (COP to multidirectional surface perturbations of subjects with vestibular deficits were used for model parameterization and validation in multiple perturbation directions and for multiple display resolutions. The quality of fit was quantified using average error and cross-correlation values. Results The mean of the average errors across all tactor configurations and perturbations was 0.24° for body sway and 0.39 cm for COP. The mean of the cross-correlation value was 0.97 for both body sway and COP. Conclusions The biofeedback model developed in this study is capable of capturing experimental response trajectory shapes with low average errors and high cross-correlation values in both the anterior-posterior and medial-lateral directions for all perturbation directions and spatial resolution display configurations considered. The results validate that biofeedback can be modeled as an additional

  6. A mathematical model for incorporating biofeedback into human postural control

    Science.gov (United States)

    2013-01-01

    Background Biofeedback of body motion can serve as a balance aid and rehabilitation tool. To date, mathematical models considering the integration of biofeedback into postural control have represented this integration as a sensory addition and limited their application to a single degree-of-freedom representation of the body. This study has two objectives: 1) to develop a scalable method for incorporating biofeedback into postural control that is independent of the model’s degrees of freedom, how it handles sensory integration, and the modeling of its postural controller; and 2) to validate this new model using multidirectional perturbation experimental results. Methods Biofeedback was modeled as an additional torque to the postural controller torque. For validation, this biofeedback modeling approach was applied to a vibrotactile biofeedback device and incorporated into a two-link multibody model with full-state-feedback control that represents the dynamics of bipedal stance. Average response trajectories of body sway and center of pressure (COP) to multidirectional surface perturbations of subjects with vestibular deficits were used for model parameterization and validation in multiple perturbation directions and for multiple display resolutions. The quality of fit was quantified using average error and cross-correlation values. Results The mean of the average errors across all tactor configurations and perturbations was 0.24° for body sway and 0.39 cm for COP. The mean of the cross-correlation value was 0.97 for both body sway and COP. Conclusions The biofeedback model developed in this study is capable of capturing experimental response trajectory shapes with low average errors and high cross-correlation values in both the anterior-posterior and medial-lateral directions for all perturbation directions and spatial resolution display configurations considered. The results validate that biofeedback can be modeled as an additional torque to the postural

  7. Tension and relaxation in the individual.

    Science.gov (United States)

    Newbury, C R

    1979-06-01

    Increasing materialism in society is resulting in more wide spread nervous tension in all age groups. While some degree of nervous tension is necessary in everyday living, its adverse effects require that we must learn to bring it under control. Total tension is shown to have two components: a controllable element arising from factors in the environment and the inbuilt uncontrollable residue which is basic in the individual temperament. The effects of excessive or uncontrolled stress can be classified as 1) emotional reactions such as neurotic behaviour (anxiety hypochondria, hysteria, phobia, depression obsessions and compulsions) or psychotic behaviour and 2) psychosomatic reactions (nervous asthma, headache, insomnia, heart attack). Nervous energy can be wastefully expended by such factors as loss of temper, wrong attitudes to work, job frustration and marital strains. Relaxation is the only positive way to control undesirable nervous tension and its techniques require to be learned. A number of techniques (progressive relaxation, differential relaxation, hypnosis, the use of biofeedback, Yoga and Transcendental Meditation) are described and their application to dental practice is discussed.

  8. Biofeedback and Counseling for Stress and Anxiety among College Students

    Science.gov (United States)

    Ratanasiripong, Paul; Sverduk, Kevin; Prince, Judy; Hayashino, Diane

    2012-01-01

    With the rise in stress and anxiety among college students, there is a need for more comprehensive and effective counseling options for counselors in college counseling centers. This study investigated the impact of using biofeedback and brief counseling in treating stress and anxiety in an ethnically diverse college student population. Results…

  9. The use of EEG Biofeedback/Neurofeedback in psychiatric rehabilitation.

    Science.gov (United States)

    Markiewcz, Renata

    2017-12-30

    The aim of the systematic review was to evaluate the use of EEG Biofeedback/Neurofeedback in patients treated for mental disorders. The review covered publications analyzing influences and effects of therapy in patients receiving psychiatric treatment based on EEG Biofeedback/Neurofeedback. Selection of publications was made by searching PubMed and Scopus databases. 328 records concerning applications of the presented method were identified in total, including 84 records for patients diagnosed with mental disorders. The analysis of studies indicates that EEG Biofeedback/Neurofeedback is used for treatment of neurological, somatic and mental disorders. Its psychiatric applications for clinically diagnosed disorders include treatmentof depression, anorexia, dyslexia, dysgraphia, ADD, ADHD, schizophrenia, abuse of substances, neuroses, PTSD, and Alzheimer's disease. Research results imply that the neuromodulating effect of the therapy positively influences cognitive processes, mood, and anxiety levels. Positive effects of EEG Biofeedback confirm usefulness of this method as a main or auxiliary method in treatment of people with mental disorders. On the basis of conducted studies, it is worthwhile to consider inclusion of this method into the comprehensive neurorehabilitation activities.

  10. Temperature biofeedback and sleep: limited findings and methodological challenges

    Directory of Open Access Journals (Sweden)

    De Koninck J

    2012-10-01

    Full Text Available Geneviève Forest,1,2 Cameron van den Heuvel,3 Kurt Lushington,4 Joseph De Koninck21Sleep Laboratory, Département de Psychoéducation et de Psychologie, Université du Québec en Outaouais, Gatineau, Québec, Canada; 2Sleep and Dreams Laboratory, School of Psychology, University of Ottawa, Ottawa, Ontario, Canada; 3Research Branch University of Adelaide, South Australia, Australia; 4School of Psychology, Social Work and Social Policy, University of South Australia, South Australia, AustraliaAbstract: Given the close link between body temperature and sleep, the perspective of manipulating core and peripheral temperature by self-regulation techniques is very appealing. We report here on a series of attempts conducted independently in two laboratories to use self-regulation (biofeedback of oral (central and hand (peripheral temperature, and measured the impact on sleep-onset latency, sleep architecture, and circadian phase. We found that hand temperature was more successful than oral temperature biofeedback. Moreover, an increase in hand temperature was associated with reduced sleep-onset latency. However, most participants found the procedure difficult to implement. The temperature response to biofeedback was reduced in the aged and weakest at the time of sleep onset, and there was not a systematic relationship between the change in temperature and change in sleep latency. Methodological limitations and individual differences may account for these results. Recommendations for future research are presented.Keywords: biofeedback, core body temperature, sleep, circadian rhythm, sleep onset

  11. Direction of Attentional Focus in Biofeedback Treatment for /R/ Misarticulation

    Science.gov (United States)

    McAllister Byun, Tara; Swartz, Michelle T.; Halpin, Peter F.; Szeredi, Daniel; Maas, Edwin

    2016-01-01

    Background: Maintaining an external direction of focus during practice is reported to facilitate acquisition of non-speech motor skills, but it is not known whether these findings also apply to treatment for speech errors. This question has particular relevance for treatment incorporating visual biofeedback, where clinician cueing can direct the…

  12. Biofeedback treatment of chronic constipation: myths and misconceptions.

    Science.gov (United States)

    Chiarioni, G

    2016-09-01

    Chronic constipation is a prevalent disorder with considerable impact on healthcare costs and quality of life. Most patients would respond to conservative measures in primary care. Patients with refractory constipation are commonly referred to dedicated centers for appropriate investigations and management. After testing, three main subtypes of constipation are commonly identified: normal colon transit, slow transit, and functional defecation disorders. The etiology of functional defecation disorders is consistent with maladaptive behavior, and biofeedback therapy has been considered a valuable treatment option. Being safe and only marginally invasive, retraining has been historically employed to manage all types of refractory constipation. There are a number of strongly held beliefs about biofeedback therapy that are not evidence-based. The aim of this review was to address these beliefs concerning protocols, efficacy, indications, and safety, with a special focus on the relevance of identifying patients with a functional defecation disorder who are ideal candidates for retraining. Randomized controlled trials support the effectiveness of biofeedback therapy for severe, refractory constipation due to functional defecation disorders. Limitations of the treatment are discussed, but biofeedback remains the safest option to successfully manage this hard-to-treat subtype of constipation.

  13. Objective versus subjective outcome measures of biofeedback: what really matters?

    Science.gov (United States)

    Berry, Amanda; Rudick, Kristen; Richter, Meg; Zderic, Stephen

    2014-08-01

    Clinical epidemiologic studies suggest that once established, voiding dysfunction can become a lifelong condition if not treated correctly early on in life. Biofeedback is one component of a voiding retraining program to help children with voiding dysfunction. Our goal was to compare objective non-invasive urodynamic data obtained during office biofeedback sessions with patient reported voiding symptom scores. Charts of 55 children referred in 2010 for pelvic floor muscle biofeedback therapy for urinary incontinence were retrospectively reviewed. Patients with any anatomic diagnoses were excluded. Forty-seven (86%) females and eight males (14%) with a mean age of 8.2 years made up the cohort. Uroflow curves, voided volumes, and post-void residuals were recorded at each visit and served as objective data. Volumes were normalized as a percentage of expected bladder capacity according to age. The patient reported symptom score and patient reported outcome (improved, no change or worse) served as subjective measures of intervention. The primary referral diagnoses were day and night wetting in 37 (67%) and daytime incontinence in 18 (33%) children. A history of urinary tract infection (UTI) was noted in 32 (64%) patients, and 25% were maintained on antibiotic prophylaxis during the study period. Twenty-nine percent were maintained on anticholinergic medication. Patients attended an average of 2.5 biofeedback sessions. Voided volumes and post void residual volumes were unchanged, 50% of the abnormal uroflow curves normalized over the course of treatment (p biofeedback were rated an improved in 26 (47%), no change in 15 (27%), worse in three (5%) patients, and not rated in 11 patients (21%). Pelvic floor muscle biofeedback is associated with patient-reported improvement in symptoms, reduction in voiding symptom score, and normalization of uroflow curves, but these improvements are not correlated with objective parameters of voided volumes and post-void residual urine

  14. Improved thermal stability and hole mobilities in a strained-Si/strained-Si1-yGe y/strained-Si heterostructure grown on a relaxed Si1-xGe x buffer

    International Nuclear Information System (INIS)

    Gupta, Saurabh; Lee, Minjoo L.; Isaacson, David M.; Fitzgerald, Eugene A.

    2005-01-01

    A dual channel heterostructure consisting of strained-Si/strained-Si 1-y Ge y on relaxed Si 1-x Ge x (y > x), provides a platform for fabricating metal-oxide-semiconductor field-effect transistors (MOSFETs) with high hole mobilities (μ eff ) which depend directly on Ge concentration and strain in the strained-Si 1-y Ge y layer. Ge out-diffuses from the strained-Si 1-y Ge y layer into relaxed Si 1-x Ge x during high temperature processing, reducing peak Ge concentration and strain in the strained-Si 1-y Ge y layer and degrades hole μ eff in these dual channel heterostructures. A heterostructure consisting of strained-Si/strained-Si 1-y Ge y /strained-Si, referred to as a trilayer heterostructure, grown on relaxed Si 1-x Ge x has much reduced Ge out-flux from the strained-Si 1-y Ge y layer and retains higher μ eff after thermal processing. Improved hole μ eff over similar dual channel heterostructures is also observed in this heterostructure. This could be a result of preventing the hole wavefunction tunneling into the low μ eff relaxed Si 1-x Ge x layer due to the additional valence band offset provided by the underlying strained-Si layer. A diffusion coefficient has been formulated and implemented in a finite difference scheme for predicting the thermal budget of the strained SiGe heterostructures. It shows that the trilayer heterostructures have superior thermal budgets at higher Ge concentrations. Ring-shaped MOSFETs were fabricated on both platforms and subjected to various processing temperatures in order to compare the extent of μ eff reduction with thermal budget. Hole μ eff enhancements are retained to a much higher extent in a trilayer heterostructure after high temperature processing as compared to a dual channel heterostructure. The improved thermal stability and hole μ eff of a trilayer heterostructure makes it an ideal platform for fabricating high μ eff MOSFETs that can be processed over higher temperatures without significant losses in hole

  15. Effectiveness of biofeedback therapy in patients with chronic constipation

    Directory of Open Access Journals (Sweden)

    Univaldo Etsuo Sagae

    2012-03-01

    Full Text Available PURPOSE: The purpose of this study was to evaluate the effect of physical therapy in women diagnosed with chronic constipation using functional training of the pelvic floor (biofeedback. PATIENTS AND METHODS: From March 2009 to March 2010, 67 women with chronic constipation were prospectively evaluated. The patients were evaluated and the constipation score proposed by Agachan et al. was applied. Then, they were sent to biofeedback. These patients were divided into 2 groups: with anismus (group I: mean age of 46.90 years old and without anismus (group II: mean age of 44.89 years old and diagnosed by anorectal electromanometry. The treatment was performed with different exercises for each group, associated with some hygieno-dietetic directions. At the end of treatment, the constipation score was reapplied. RESULTS: Pre-biofeedback constipation score in group I was 15.04 (standard deviation - SD=2.48 and post-biofeedback constipation score was 3.39 (SD=1.62 (pOBJETIVO: Este trabalho objetivou avaliar o efeito do tratamento fisioterapêutico, em mulheres diagnosticadas com constipação crônica, utilizando treinamento funcional do assoalho pélvico (biofeedback. CASUÍSTICA E MÉTODO: No período de março de 2009 a março de 2010, foram avaliadas, prospectivamente, 67 mulheres com constipação intestinal. As pacientes foram avaliadas e o escore de constipação, proposto por Agachan et al., foi aplicado; então, foram encaminhadas ao biofeedback. Essas pacientes foram divididas em 2 grupos: com anismus (56 pacientes do grupo I: média de idade 46,90 anos e sem anismus (11 pacientes do grupo II: média de idade 44,89 anos, diagnosticadas pela eletromanometria anorretal. Para o tratamento, foram estipulados exercícios diferentes para cada grupo, associados com orientações higienodietéticas. Ao fim do tratamento, foi reaplicado o escore de constipação. RESULTADOS: O escore de constipação do grupo I, na avaliação pré-biofeedback, foi 15

  16. Patterns of anismus and the relation to biofeedback therapy.

    Science.gov (United States)

    Park, U C; Choi, S K; Piccirillo, M F; Verzaro, R; Wexner, S D

    1996-07-01

    A study was undertaken to assess physiologic characteristics and clinical significance of anismus. Specifically, we sought to assess patterns of anismus and the relation of these findings to the success of therapy. Sixty-eight patients were found to have anismus based on history and diagnostic criteria including anismus by defecography and at least one of three additional tests: anorectal manometry, electromyography, or colonic transit time study. Interpretation of defecography was based on the consensus of at least three of four observers. Anal canal hypertonia (n = 32) was defined when mean and maximum resting pressures were at least 1 standard deviation higher than those in 63 controls. There were two distinct defecographic patterns of anismus: Type A (n = 26), a flattened anorectal angle without definitive puborectalis indentation but a closed anal canal; Type B (n = 42), a clear puborectalis indentation, narrow anorectal angle, and closed anal canal. Outcomes of 57 patients who had electromyographybased biofeedback therapy were reported as either improved or unimproved at a mean follow-up of 23.7 (range, 6-62) months. These two types of anismus were compared with biofeedback outcome to assess clinical relevance. Patients with Type A anismus showed greater perineal descent at rest (mean, 5.1 vs. 3.5 cm; P anismus. Only 25 percent of patients who had Type A anismus with anal canal hypertonia were improved by biofeedback therapy. Conversely, 86 percent of patients with Type B anismus without anal canal hypertonia were successfully treated with biofeedback (P anismus correlate with the success of biofeedback treatment. Therefore, knowledge of these patterns may help direct therapy.

  17. Improving biofeedback for the treatment of fecal incontinence in women: implementation of a standardized multi-site manometric biofeedback protocol.

    Science.gov (United States)

    Markland, A D; Jelovsek, J E; Whitehead, W E; Newman, D K; Andy, U U; Dyer, K; Harm-Ernandes, I; Cichowski, S; McCormick, J; Rardin, C; Sutkin, G; Shaffer, A; Meikle, S

    2017-01-01

    Standardized training and clinical protocols using biofeedback for the treatment of fecal incontinence (FI) are important for clinical care. Our primary aims were to develop, implement, and evaluate adherence to a standardized protocol for manometric biofeedback to treat FI. In a Pelvic Floor Disorders Network (PFDN) trial, participants were enrolled from eight PFDN clinical centers across the United States. A team of clinical and equipment experts developed biofeedback software on a novel tablet computer platform for conducting standardized anorectal manometry with separate manometric biofeedback protocols for improving anorectal muscle strength, sensation, and urge resistance. The training protocol also included education on bowel function, anal sphincter exercises, and bowel diary monitoring. Study interventionists completed online training prior to attending a centralized, standardized certification course. For the certification, expert trainers assessed the ability of the interventionists to perform the protocol components for a paid volunteer who acted as a standardized patient. Postcertification, the trainers audited interventionists during trial implementation to improve protocol adherence. Twenty-four interventionists attended the in-person training and certification, including 46% advanced practice registered nurses (11/24), 50% (12/24) physical therapists, and 4% physician assistants (1/24). Trainers performed audio audits for 88% (21/24), representing 84 audited visits. All certified interventionists met or exceeded the prespecified 80% pass rate for the audit process, with an average passing rate of 93%. A biofeedback protocol can be successfully imparted to experienced pelvic floor health care providers from various disciplines. Our process promoted high adherence to a standard protocol and is applicable to many clinical settings. © 2016 John Wiley & Sons Ltd.

  18. Multiscale dipole relaxation in dielectric materials

    DEFF Research Database (Denmark)

    Hansen, Jesper Schmidt

    2016-01-01

    Dipole relaxation from thermally induced perturbations is investigated on different length scales for dielectric materials. From the continuum dynamical equations for the polarisation, expressions for the transverse and longitudinal dipole autocorrelation functions are derived in the limit where ...

  19. Effect of thermal annealing on electron spin relaxation of beryllium-doped In{sub 0.8}Ga{sub 0.2}As{sub 0.45}P{sub 0.55} bulk

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Hao; Harasawa, Ryo; Yasue, Yuya; Aritake, Takanori; Jiang, Canyu; Tackeuchi, Atsushi, E-mail: atacke@waseda.jp [Department of Applied Physics, Waseda University, Shinjuku, Tokyo 169-8555 (Japan); Ji, Lian; Lu, Shulong [Suzhou Institute of Nano-tech and Nano-bionics, Chinese Academy of Sciences, Dushu Lake Higher Education Town, Ruoshui Road 398, Suzhou Industrial Park, Suzhou (China)

    2016-08-15

    The effect of thermal annealing on the electron spin relaxation of beryllium-doped In{sub 0.8}Ga{sub 0.2}As{sub 0.45}P{sub 0.55} bulk was investigated by time-resolved spin-dependent pump and probe reflection measurement with a high time resolution of 200 fs. Three similar InGaAsP samples were examined one of which was annealed at 800 °C for 1 s, one was annealed at 700 °C for 1 s and the other was not annealed after crystal growth by molecular beam epitaxy. Although the carrier lifetimes of the 700 °C-annealed sample and the unannealed sample were similar, that of the 800 °C-annealed sample was extended to 11.6 (10.4) ns at 10 (300) K, which was more than two (four) times those of the other samples. However, interestingly the spin relaxation time of the 800 °C-annealed sample was found to be similar to those of the other two samples. Particularly at room temperature, the spin relaxation times are 143 ps, 147 ps, and 111 ps for the 800 °C-annealed sample, 700 °C-annealed sample, and the unannealed sample, respectively.

  20. Effect of thermal annealing on electron spin relaxation of beryllium-doped In0.8Ga0.2As0.45P0.55 bulk

    Directory of Open Access Journals (Sweden)

    Hao Wu

    2016-08-01

    Full Text Available The effect of thermal annealing on the electron spin relaxation of beryllium-doped In0.8Ga0.2As0.45P0.55 bulk was investigated by time-resolved spin-dependent pump and probe reflection measurement with a high time resolution of 200 fs. Three similar InGaAsP samples were examined one of which was annealed at 800 °C for 1 s, one was annealed at 700 °C for 1 s and the other was not annealed after crystal growth by molecular beam epitaxy. Although the carrier lifetimes of the 700 °C-annealed sample and the unannealed sample were similar, that of the 800 °C-annealed sample was extended to 11.6 (10.4 ns at 10 (300 K, which was more than two (four times those of the other samples. However, interestingly the spin relaxation time of the 800 °C-annealed sample was found to be similar to those of the other two samples. Particularly at room temperature, the spin relaxation times are 143 ps, 147 ps, and 111 ps for the 800 °C-annealed sample, 700 °C-annealed sample, and the unannealed sample, respectively.

  1. Suitability of Smartphone Inertial Sensors for Real-Time Biofeedback Applications

    Science.gov (United States)

    Kos, Anton; Tomažič, Sašo; Umek, Anton

    2016-01-01

    This article studies the suitability of smartphones with built-in inertial sensors for biofeedback applications. Biofeedback systems use various sensors to measure body functions and parameters. These sensor data are analyzed, and the results are communicated back to the user, who then tries to act on the feedback signals. Smartphone inertial sensors can be used to capture body movements in biomechanical biofeedback systems. These sensors exhibit various inaccuracies that induce significant angular and positional errors. We studied deterministic and random errors of smartphone accelerometers and gyroscopes, primarily focusing on their biases. Based on extensive measurements, we determined accelerometer and gyroscope noise models and bias variation ranges. Then, we compiled a table of predicted positional and angular errors under various biofeedback system operation conditions. We suggest several bias compensation options that are suitable for various examples of use in real-time biofeedback applications. Measurements within the developed experimental biofeedback application show that under certain conditions, even uncompensated sensors can be used for real-time biofeedback. For general use, especially for more demanding biofeedback applications, sensor biases should be compensated. We are convinced that real-time biofeedback systems based on smartphone inertial sensors are applicable to many similar examples in sports, healthcare, and other areas. PMID:26927125

  2. Comparing the Efficacy of Biofeedback and Balloon-Assisted Training in the Treatment of Dyssynergic Defecation

    Directory of Open Access Journals (Sweden)

    Abbs Ali Pourmomeny

    2011-01-01

    Full Text Available BACKGROUND: Dyssynergic defecation does not respond appropriately to routine treatments for constipation. Recently, research has shown that biofeedback therapy is useful in anorectal dyssynergia.

  3. Suitability of Smartphone Inertial Sensors for Real-Time Biofeedback Applications.

    Science.gov (United States)

    Kos, Anton; Tomažič, Sašo; Umek, Anton

    2016-02-27

    This article studies the suitability of smartphones with built-in inertial sensors for biofeedback applications. Biofeedback systems use various sensors to measure body functions and parameters. These sensor data are analyzed, and the results are communicated back to the user, who then tries to act on the feedback signals. Smartphone inertial sensors can be used to capture body movements in biomechanical biofeedback systems. These sensors exhibit various inaccuracies that induce significant angular and positional errors. We studied deterministic and random errors of smartphone accelerometers and gyroscopes, primarily focusing on their biases. Based on extensive measurements, we determined accelerometer and gyroscope noise models and bias variation ranges. Then, we compiled a table of predicted positional and angular errors under various biofeedback system operation conditions. We suggest several bias compensation options that are suitable for various examples of use in real-time biofeedback applications. Measurements within the developed experimental biofeedback application show that under certain conditions, even uncompensated sensors can be used for real-time biofeedback. For general use, especially for more demanding biofeedback applications, sensor biases should be compensated. We are convinced that real-time biofeedback systems based on smartphone inertial sensors are applicable to many similar examples in sports, healthcare, and other areas.

  4. Heart rate variability biofeedback intervention for reduction of psychological stress during the early postpartum period.

    Science.gov (United States)

    Kudo, Naoko; Shinohara, Hitomi; Kodama, Hideya

    2014-12-01

    This study examined the effectiveness of heart rate variability (HRV) biofeedback intervention for reduction of psychological stress in women in the early postpartum period. On postpartum day 4, 55 healthy subjects received a brief explanation about HRV biofeedback using a portable device. Among them, 25 mothers who agreed to implement HRV biofeedback at home were grouped as the biofeedback group, and other 30 mothers were grouped as the control group. At 1 month postpartum, there was a significant decrease in total Edinburgh Postnatal Depression Scale score (P biofeedback group; this change was brought about mainly by decreases in items related to anxiety or difficulty sleeping. There was also a significant increase in standard deviation of the normal heartbeat interval (P biofeedback group after adjusting for potential covariates. In conclusion, postpartum women who implemented HRV biofeedback after delivery were relatively free from anxiety and complained less of difficulties sleeping at 1 month postpartum. Although the positive effects of HRV biofeedback may be partly attributable to intervention effects, due to its clinical outcome, HRV biofeedback appears to be recommendable for many postpartum women as a feasible health-promoting measure after childbirth.

  5. Effect of visual biofeedback of posterior tongue movement on articulation rehabilitation in dysarthria patients.

    Science.gov (United States)

    Yano, J; Shirahige, C; Oki, K; Oisaka, N; Kumakura, I; Tsubahara, A; Minagi, S

    2015-08-01

    Articulation is driven by various combinations of movements of the lip, tongue, soft palate, pharynx and larynx, where the tongue plays an especially important role. In patients with cerebrovascular disorder, lingual motor function is often affected, causing dysarthria. We aimed to evaluate the effect of visual biofeedback of posterior tongue movement on articulation rehabilitation in dysarthria patients with cerebrovascular disorder. Fifteen dysarthria patients (10 men and 5 women; mean age, 70.7 ± 10.3 years) agreed to participate in this study. A device for measuring the movement of the posterior part of the tongue was used for the visual biofeedback. Subjects were instructed to produce repetitive articulation of [ka] as fast and steadily as possible between a lungful with/without visual biofeedback. For both the unaffected and affected sides, the range of ascending and descending movement of the posterior tongue with visual biofeedback was significantly larger than that without visual biofeedback. The coefficient of variation for these movements with visual biofeedback was significantly smaller than that without visual biofeedback. With visual biofeedback, the range of ascent exhibited a significant and strong correlation with that of descent for both the unaffected and affected sides. The results of this study revealed that the use of visual biofeedback leads to prompt and preferable change in the movement of the posterior part of the tongue. From the standpoint of pursuing necessary rehabilitation for patients with attention and memory disorders, visualization of tongue movement would be of marked clinical benefit. © 2015 John Wiley & Sons Ltd.

  6. Manipulation of the kinematic chain using visual biofeedback

    OpenAIRE

    Mulloy, Franky; Mullineaux, David; Irwin, Gareth

    2016-01-01

    Feedback has been shown to be an influential component in skill development, yet this has not been assessed in movements involving an explosive proximal to distal sequencing pattern. Novices (n=14) were introduced to a lunge touch task. Visual biofeedback were given on the timing and magnitude of rear leg kinematics. Results showed that those who received feedback adapted their movement patterns by developing extension velocity magnitudes in a summative pattern (pre v post, mean ± SD peak ank...

  7. Calming Children When Drawing Blood Using Breath-based Biofeedback

    OpenAIRE

    Sonne, T.; Merritt, T.; Marshall, P. E.; Lomholt, J.; Müller, J.; Grønbæk, K.

    2017-01-01

    Blood sampling is a common and necessary procedure in the treatment and diagnosis of a variety of diseases. However, it often results in painful and stressful experiences for children. Designed together with domain experts, ChillFish is a breath-controlled biofeedback game technology with bespoke airflow sensor that aims to calm children during blood sampling procedures. An experimental pilot study was conducted in which 20 children aged 6-11 were assigned to one of two conditions involving e...

  8. THE POSSIBILITY OF BIOFEEDBACK IN EDUCATIONAL ADAPTATION OF JUNIOR SCHOOLCHILDREN

    Directory of Open Access Journals (Sweden)

    Olga A. Jafarova

    2016-01-01

    Full Text Available In order to develop an effective self-regulation skills in younger students the technology of computer games biofeedback psychological state of the child. Using the virtual simulation of situations and conditions it is shown that as a result of conscious control over one’s own state, the student can develop skills of self-regulation. Described stories of gaming training, which is controlled by the heart rate of the player

  9. Biofeedback effectiveness to reduce upper limb muscle activity during computer work is muscle specific and time pressure dependent

    DEFF Research Database (Denmark)

    Vedsted, Pernille; Søgaard, Karen; Blangsted, Anne Katrine

    2011-01-01

    trapezius (TRA) can reduce bilateral TRA activity but not extensor digitorum communis (EDC) activity; (2) biofeedback from EDC can reduce activity in EDC but not in TRA; (3) biofeedback is more effective in no time constraint than in the time constraint working condition. Eleven healthy women performed......Continuous electromyographic (EMG) activity level is considered a risk factor in developing muscle disorders. EMG biofeedback is known to be useful in reducing EMG activity in working muscles during computer work. The purpose was to test the following hypotheses: (1) unilateral biofeedback from...... computer work during two different working conditions (time constraint/no time constraint) while receiving biofeedback. Biofeedback was given from right TRA or EDC through two modes (visual/auditory) by the use of EMG or mechanomyography as biofeedback source. During control sessions (no biofeedback), EMG...

  10. Biofeedback Training in Crisis Managers: A Randomized Controlled Trial.

    Science.gov (United States)

    Janka, A; Adler, C; Brunner, B; Oppenrieder, S; Duschek, S

    2017-06-01

    Working in crisis environments represents a major challenge, especially for executive personnel engaged in directing disaster operations, i.e. crisis managers. Crisis management involves operating under conditions of extreme stress resulting, for instance, from high-level decision-making, principal responsibility for personnel, multitasking or working under conditions of risk and time pressure. The present study aimed to investigate the efficacy of a newly developed biofeedback training procedure based on electrodermal activity, especially designed for the target group of crisis managers. The training comprised exercises promoting acquisition of control over sympathetic arousal under resting conditions and during exposure to visual, acoustic and cognitive stressors resembling situations related to crisis management. In a randomized controlled design, 36 crisis managers were assigned to either a biofeedback training group or waiting list control group. Subjective stress was assessed using the Perceived Stress Scale. In the training group, stress level markedly decreased; the decrease remained stable at follow-up 2 months after the training. The results indicate that biofeedback training in crisis management is an effective method for stress management that may help to reduce vulnerability to stress-related performance decline and stress-related disease.

  11. CONDENSED MATTER: STRUCTURE, MECHANICAL, AND THERMAL PROPERTIES: Observation of β-Relaxation in Sub-Tg Isothermally Annealed Al-Based Metallic Glasses

    Science.gov (United States)

    Yang, Hong-Wang; Tong, Wei-Ping; Zhao, Xiang; Zuo, Liang; Wang, Jian-Qiang

    2008-09-01

    Al85 Ni5 Y8 C02 and Al 85 Ni5 Y6 C02 Fe2 metallic glasses are fabricated by melt spinning. A kink or a small exothermic peak is observed for both the samples isothermally annealed at sub-glass transition temperatures. Temperature modulated differential scanning calorimetry (TMDSC) data disapprove amorphous phase separation. The activation energies derived from Kissinger plots of the exothermic process on DSC curve around glass transition temperature are consistent with those of β -relaxation of metallic glasses.

  12. Learning effects of dynamic postural control by auditory biofeedback versus visual biofeedback training.

    Science.gov (United States)

    Hasegawa, Naoya; Takeda, Kenta; Sakuma, Moe; Mani, Hiroki; Maejima, Hiroshi; Asaka, Tadayoshi

    2017-10-01

    Augmented sensory biofeedback (BF) for postural control is widely used to improve postural stability. However, the effective sensory information in BF systems of motor learning for postural control is still unknown. The purpose of this study was to investigate the learning effects of visual versus auditory BF training in dynamic postural control. Eighteen healthy young adults were randomly divided into two groups (visual BF and auditory BF). In test sessions, participants were asked to bring the real-time center of pressure (COP) in line with a hidden target by body sway in the sagittal plane. The target moved in seven cycles of sine curves at 0.23Hz in the vertical direction on a monitor. In training sessions, the visual and auditory BF groups were required to change the magnitude of a visual circle and a sound, respectively, according to the distance between the COP and target in order to reach the target. The perceptual magnitudes of visual and auditory BF were equalized according to Stevens' power law. At the retention test, the auditory but not visual BF group demonstrated decreased postural performance errors in both the spatial and temporal parameters under the no-feedback condition. These findings suggest that visual BF increases the dependence on visual information to control postural performance, while auditory BF may enhance the integration of the proprioceptive sensory system, which contributes to motor learning without BF. These results suggest that auditory BF training improves motor learning of dynamic postural control. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. Biofeedback for training balance and mobility tasks in older populations : a systematic review

    NARCIS (Netherlands)

    Zijlstra, Agnes; Mancini, Martina; Chiari, Lorenzo; Zijlstra, Wiebren

    2010-01-01

    Context: An effective application of biofeedback for interventions in older adults with balance and mobility disorders may be compromised due to co-morbidity. Objective: To evaluate the feasibility and the effectiveness of biofeedback-based training of balance and/or mobility in older adults. Data

  14. Haptic biofeedback for improving compliance with lower-extremity partial weight bearing.

    Science.gov (United States)

    Fu, Michael C; DeLuke, Levi; Buerba, Rafael A; Fan, Richard E; Zheng, Ying Jean; Leslie, Michael P; Baumgaertner, Michael R; Grauer, Jonathan N

    2014-11-01

    After lower-extremity orthopedic trauma and surgery, patients are often advised to restrict weight bearing on the affected limb. Conventional training methods are not effective at enabling patients to comply with recommendations for partial weight bearing. The current study assessed a novel method of using real-time haptic (vibratory/vibrotactile) biofeedback to improve compliance with instructions for partial weight bearing. Thirty healthy, asymptomatic participants were randomized into 1 of 3 groups: verbal instruction, bathroom scale training, and haptic biofeedback. Participants were instructed to restrict lower-extremity weight bearing in a walking boot with crutches to 25 lb, with an acceptable range of 15 to 35 lb. A custom weight bearing sensor and biofeedback system was attached to all participants, but only those in the haptic biofeedback group were given a vibrotactile signal if they exceeded the acceptable range. Weight bearing in all groups was measured with a separate validated commercial system. The verbal instruction group bore an average of 60.3±30.5 lb (mean±standard deviation). The bathroom scale group averaged 43.8±17.2 lb, whereas the haptic biofeedback group averaged 22.4±9.1 lb (Phaptic biofeedback group averaged 14.5±6.3% (Phaptic biofeedback to improve compliance with lower-extremity partial weight bearing, haptic biofeedback was superior to conventional physical therapy methods. Further studies in patients with clinical orthopedic trauma are warranted. Copyright 2014, SLACK Incorporated.

  15. Biofeedback as complementary treatment in patients with epilepsy – an underestimated therapeutic option? Review, results, discussion

    Directory of Open Access Journals (Sweden)

    Uhlmann Carmen

    2016-12-01

    Full Text Available Background. Biofeedback methods represent side effect free complementary options in the treatment of epilepsy. In this paper we review the current status of these methods in terms of clinical study results and their evaluation by systematic review papers. Possible mechanisms of action in biofeedback methods are discussed.

  16. Biofeedback for stress reduction: towards a brigth future for a revitalized field

    NARCIS (Netherlands)

    Van den Broek, E.L.; Westerink, J.H.D.

    2012-01-01

    Stress has recently been baptized as the black death of the 21st century, which illustrates its threat to current health standards. Thisarticle proposes biofeedback systems as a means to reduce stress. Aconcise state-ofthe-art introduction on biofeedback systems is given. The field of mental health

  17. Biofeedback and physiotherapy versus physiotherapy alone in the treatment of genuine stress urinary incontinence

    DEFF Research Database (Denmark)

    Glavind, K; Nøhr, S B; Walter, S

    1996-01-01

    Biofeedback is a method of pelvic floor rehabilitation using a surface electrode inserted into the vagina and a catheter in the rectum. Forty women with genuine urinary stress incontinence were randomized to compare the efficacy of physiotherapy and physiotherapy in combination with biofeedback...

  18. DEEP: A biofeedback virtual reality game for children at-risk for anxiety

    NARCIS (Netherlands)

    Rooij, M.M.J.W. van; Lobel, A.M.; Harris, O.; Smit, N.; Granic, I.

    2016-01-01

    Biofeedback games have the potential to make gaming a deeply personal experience by linking the gamespace to each player's physiological state. First, this paper describes the psycho-educational potential of the horror-themed biofeedback game Nevermind. In Nevermind, players' heart rate is

  19. First clinical implementation of audiovisual biofeedback in liver cancer stereotactic body radiation therapy

    International Nuclear Information System (INIS)

    Pollock, Sean; Tse, Regina; Martin, Darren

    2015-01-01

    This case report details a clinical trial's first recruited liver cancer patient who underwent a course of stereotactic body radiation therapy treatment utilising audiovisual biofeedback breathing guidance. Breathing motion results for both abdominal wall motion and tumour motion are included. Patient 1 demonstrated improved breathing motion regularity with audiovisual biofeedback. A training effect was also observed.

  20. Biofeedback systems for stress reduction: Towards a Bright Future for a Revitalized Field

    NARCIS (Netherlands)

    van den Broek, Egon; Westerink, Joyce H.D.M.; Conchon, E.; Correia, C.; Fred, A.; Gamboa, H.

    2012-01-01

    Stress has recently been baptized as the black death of the 21st century, which illustrates its threat to current health standards. This article proposes biofeedback systems as a means to reduce stress. A concise state-ofthe-art introduction on biofeedback systems is given. The field of mental

  1. Biofeedback systems for stress reduction : Towards a bright future for a revitalized field

    NARCIS (Netherlands)

    Broek, E.L. van den; Westerink, J.H.D.M.

    2012-01-01

    Stress has recently been baptized as the black death of the 21st century, which illustrates its threat to current health standards. This article proposes biofeedback systems as a means to reduce stress. A concise state-of-the-art introduction on biofeedback systems is given. The field of mental

  2. Is EEG-biofeedback an effective treatment in autism spectrum disorders? A randomized controlled trial

    NARCIS (Netherlands)

    Kouijzer, M.E.J.; Schie, H.T. van; Gerrits, B.J.L.; Buitelaar, J.K.; Moor, J.M.H. de

    2013-01-01

    EEG-biofeedback has been reported to reduce symptoms of autism spectrum disorders (ASD) in several studies. However, these studies did not control for nonspecific effects of EEG-biofeedback and did not distinguish between participants who succeeded in influencing their own EEG activity and

  3. Using a False Biofeedback Methodology to Explore Relationships between Learners' Affect, Metacognition, and Performance

    Science.gov (United States)

    Strain, Amber Chauncey; Azevedo, Roger; D'Mello, Sidney K.

    2013-01-01

    We used a false-biofeedback methodology to manipulate physiological arousal in order to induce affective states that would influence learners' metacognitive judgments and learning performance. False-biofeedback is a method used to induce physiological arousal (and resultant affective states) by presenting learners with audio stimuli of false heart…

  4. Heart rate variability biofeedback reduces food cravings in high food cravers.

    Science.gov (United States)

    Meule, Adrian; Freund, Rebecca; Skirde, Ann Kathrin; Vögele, Claus; Kübler, Andrea

    2012-12-01

    Heart rate variability (HRV) biofeedback has been reported to increase HRV while decreasing symptoms in patients with mental disorders. In addition, associations between low HRV and lowered self-regulation were found in non-clinical samples, e.g., in individuals with strong chocolate cravings or unsuccessful dieting. The current study aimed at decreasing food cravings with HRV-biofeedback in individuals frequently experiencing such cravings. Participants (N = 56) with strong or low food cravings associated with a lack of control over eating were selected from the local community. Half of the participants with strong cravings (craving-biofeedback; n = 14) performed 12 sessions of HRV-biofeedback while the other half (craving-control; n = 14) and a group with low cravings (non-craving-control; n = 28) received no intervention. Subjective food cravings related to a lack of control over eating decreased from pre- to post-measurement in the craving-biofeedback group, but remained constant in the control groups. Moreover, only the craving-biofeedback group showed a decrease in eating and weight concerns. Although HRV-biofeedback was successful in reducing food cravings, this change was not accompanied by an increase in HRV. Instead, HRV decreased in the craving-control group. This study provides preliminary evidence that HRV-biofeedback could be beneficial for attenuating dysfunctional eating behavior although specific mechanisms remain to be elucidated.

  5. Integrating Course Work With Field Work Placements in Undergraduate Clinical Biofeedback.

    Science.gov (United States)

    Motiff, James P.

    The three major aspects of the clinical biofeedback experience for undergraduates at Hope College, Holland, Michigan are presented in terms of the academic program, the actual clinical experience, and the procedures for becoming certified as a "biofeedback assistant." The academic program is detailed, including the requirements for…

  6. Designing and utilizing biofeedback games for emotion regulation: The case of Nevermind

    NARCIS (Netherlands)

    Lobel, A.M.; Gotsis, M.; Reynolds, E.; Annetta, M.; Engels, R.C.M.E.; Granic, I.

    2016-01-01

    Biofeedback games have the potential to make gaming a deeply personal experience by linking the gamespace to each player's physiological state. First, this paper describes the psycho-educational potential of the horror-themed biofeedback game Nevermind. In Nevermind, players' heart rate is

  7. Effect of neurofeedback and electromyographic-biofeedback therapy on improving hand function in stroke patients.

    Science.gov (United States)

    Rayegani, S M; Raeissadat, S A; Sedighipour, L; Rezazadeh, I Mohammad; Bahrami, M H; Eliaspour, D; Khosrawi, S

    2014-01-01

    The aim of the present study was to evaluate the effect of applying electroencephalogram (EEG) biofeedback (neurobiofeedback) or electromyographic (EMG) biofeedback to conventional occupational therapy (OT) on improving hand function in stroke patients. This study was designed as a preliminary clinical trial. Thirty patients with stroke were entered the study. Hand function was evaluated by Jebsen Hand Function Test pre and post intervention. Patients were allocated to 3 intervention cohorts: (1) OT, (2) OT plus EMG-biofeedback therapy, and (3) OT plus neurofeedback therapy. All patients received 10 sessions of conventional OT. Patients in cohorts 2 and 3 also received EMG-biofeedback and neurofeedback therapy, respectively. EMG-biofeedback therapy was performed to strengthen the abductor pollicis brevis (APB) muscle. Neurofeedback training was aimed at enhancing sensorimotor rhythm after mental motor imagery. Hand function was improved significantly in the 3 groups. The spectral power density of the sensorimotor rhythm band in the neurofeedback group increased after mental motor imagery. Maximum and mean contraction values of electrical activities of the APB muscle during voluntary contraction increased significantly after EMG-biofeedback training. Patients in the neurofeedback and EMG-biofeedback groups showed hand improvement similar to conventional OT. Further studies are suggested to assign the best protocol for neurofeedback and EMG-biofeedback therapy.

  8. Structural relaxation: low temperature properties

    International Nuclear Information System (INIS)

    Cruz, F. de la

    1984-01-01

    We discuss the changes in transport and superconducting properties of amorphous Zr 70 Cu 30 , induced by thermal relaxation. The experimental results are used to investigate the relation between the microscopic parameters and the observed physical properties. It is shown that the density of eletronic states determines the shift Tc as well as the variation of the electrical resistivity. It is necessary to assume strong hybridization between s and d bands to understand the eletrodynamic response of the superconductor. (Author) [pt

  9. Audiovisual Biofeedback Improves Cine–Magnetic Resonance Imaging Measured Lung Tumor Motion Consistency

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Danny [Radiation Physics Laboratory, Sydney Medical School, The University of Sydney, Sidney, NSW (Australia); Greer, Peter B. [School of Mathematical and Physical Sciences, The University of Newcastle, Newcastle, NSW (Australia); Department of Radiation Oncology, Calvary Mater Newcastle, Newcastle, NSW (Australia); Ludbrook, Joanna; Arm, Jameen; Hunter, Perry [Department of Radiation Oncology, Calvary Mater Newcastle, Newcastle, NSW (Australia); Pollock, Sean; Makhija, Kuldeep; O' brien, Ricky T. [Radiation Physics Laboratory, Sydney Medical School, The University of Sydney, Sidney, NSW (Australia); Kim, Taeho [Radiation Physics Laboratory, Sydney Medical School, The University of Sydney, Sidney, NSW (Australia); Department of Radiation Oncology, Virginia Commonwealth University, Richmond, Virginia (United States); Keall, Paul, E-mail: paul.keall@sydney.edu.au [Radiation Physics Laboratory, Sydney Medical School, The University of Sydney, Sidney, NSW (Australia)

    2016-03-01

    Purpose: To assess the impact of an audiovisual (AV) biofeedback on intra- and interfraction tumor motion for lung cancer patients. Methods and Materials: Lung tumor motion was investigated in 9 lung cancer patients who underwent a breathing training session with AV biofeedback before 2 3T magnetic resonance imaging (MRI) sessions. The breathing training session was performed to allow patients to become familiar with AV biofeedback, which uses a guiding wave customized for each patient according to a reference breathing pattern. In the first MRI session (pretreatment), 2-dimensional cine-MR images with (1) free breathing (FB) and (2) AV biofeedback were obtained, and the second MRI session was repeated within 3-6 weeks (mid-treatment). Lung tumors were directly measured from cine-MR images using an auto-segmentation technique; the centroid and outlier motions of the lung tumors were measured from the segmented tumors. Free breathing and AV biofeedback were compared using several metrics: intra- and interfraction tumor motion consistency in displacement and period, and the outlier motion ratio. Results: Compared with FB, AV biofeedback improved intrafraction tumor motion consistency by 34% in displacement (P=.019) and by 73% in period (P<.001). Compared with FB, AV biofeedback improved interfraction tumor motion consistency by 42% in displacement (P<.046) and by 74% in period (P=.005). Compared with FB, AV biofeedback reduced the outlier motion ratio by 21% (P<.001). Conclusions: These results demonstrated that AV biofeedback significantly improved intra- and interfraction lung tumor motion consistency for lung cancer patients. These results demonstrate that AV biofeedback can facilitate consistent tumor motion, which is advantageous toward achieving more accurate medical imaging and radiation therapy procedures.

  10. Audiovisual Biofeedback Improves Cine–Magnetic Resonance Imaging Measured Lung Tumor Motion Consistency

    International Nuclear Information System (INIS)

    Lee, Danny; Greer, Peter B.; Ludbrook, Joanna; Arm, Jameen; Hunter, Perry; Pollock, Sean; Makhija, Kuldeep; O'brien, Ricky T.; Kim, Taeho; Keall, Paul

    2016-01-01

    Purpose: To assess the impact of an audiovisual (AV) biofeedback on intra- and interfraction tumor motion for lung cancer patients. Methods and Materials: Lung tumor motion was investigated in 9 lung cancer patients who underwent a breathing training session with AV biofeedback before 2 3T magnetic resonance imaging (MRI) sessions. The breathing training session was performed to allow patients to become familiar with AV biofeedback, which uses a guiding wave customized for each patient according to a reference breathing pattern. In the first MRI session (pretreatment), 2-dimensional cine-MR images with (1) free breathing (FB) and (2) AV biofeedback were obtained, and the second MRI session was repeated within 3-6 weeks (mid-treatment). Lung tumors were directly measured from cine-MR images using an auto-segmentation technique; the centroid and outlier motions of the lung tumors were measured from the segmented tumors. Free breathing and AV biofeedback were compared using several metrics: intra- and interfraction tumor motion consistency in displacement and period, and the outlier motion ratio. Results: Compared with FB, AV biofeedback improved intrafraction tumor motion consistency by 34% in displacement (P=.019) and by 73% in period (P<.001). Compared with FB, AV biofeedback improved interfraction tumor motion consistency by 42% in displacement (P<.046) and by 74% in period (P=.005). Compared with FB, AV biofeedback reduced the outlier motion ratio by 21% (P<.001). Conclusions: These results demonstrated that AV biofeedback significantly improved intra- and interfraction lung tumor motion consistency for lung cancer patients. These results demonstrate that AV biofeedback can facilitate consistent tumor motion, which is advantageous toward achieving more accurate medical imaging and radiation therapy procedures.

  11. Stress relaxation under cyclic electron irradiation

    International Nuclear Information System (INIS)

    Bystrov, L.N.; Reznitskij, M.E.

    1990-01-01

    The kinetics of deformation process in a relaxating sample under 2 MeV electron cyclic irradiation was studied experimentally. The Al-Mg alloys with controllable and different (in dislocation density precipitate presence and their character) structure were used in experiments. It was established that after the beam was switched on the deformation rate increased sharply and then, during prolonged irradiation, in a gradual manner. After the switching-off the relaxation rate decreases by jumps up to values close to extrapolated rates of pre-radiation relaxation. The exhibition of these effects with radiation switching-off and switchin-on is dependent on the initial rate of thermal relaxation, the test temperature, the preliminary cold deformation and the dominating deformation dislocation mechanism. The preliminary cold deformation and test temperature elevation slightly decrease the effect of instantaneous relaxation acceleration with the irradiation switch-on. 17 refs., 5 figs

  12. Breathing and Relaxation

    Science.gov (United States)

    ... Find a Doctor Relaxation is the absence of tension in muscle groups and a minimum or absence ... Drill Meditation Progressive Muscle Relaxation Minimizing Shortness of Breath Visualization This information has been approved by Shelby ...

  13. Pelvic floor exercises with biofeedback for stress urinary incontinence

    Directory of Open Access Journals (Sweden)

    Maria V. Capelini

    2006-08-01

    Full Text Available OBJECTIVE: Prospective study to objectively evaluate the benefits of pelvic floor strengthening exercises associated to biofeedback for the treatment of stress urinary incontinence. MATERIALS AND METHODS: Fourteen patients diagnosed with stress urinary incontinence (SUI were selected for this study. All patients underwent a pelvic floor training associated to biofeedback for 12 consecutive weeks. Urodynamic tests, pad test and bladder diary were analyzed at the beginning of the study, at the end and after 3 months. The King's Health Questionnaire (KHQ was applied before and after treatment to assess the impact in the quality of life. RESULTS: There was a significant reduction in the pad weight (from 14.21 g to 1 g, number of urinary leakage episodes (from 8.14 per day to 2.57 per day and daytime frequency (from 7.93 per day to 5.85 per day. At urodynamics the authors observed a significant increase in Valsalva leak-point pressure (from 103.93 cm H2O to 139.14 cm H2O, cistometric capacity (from 249.29 mL to 336.43 mL, p = 0.0015 and bladder volume at first desire to void (from 145 mL to 215.71 mL. Those differences were kept during the first 3 months of follow up. The KHQ revealed significant differences except in the case of "general health perception", which covers health in general and not exclusively urinary incontinence. CONCLUSION: Treatment of SUI with pelvic floor exercises associated to biofeedback caused significant changes in the parameters analyzed, with maintenance of good results 3 months after treatment.

  14. Heart rate variability biofeedback: how and why does it work?

    Science.gov (United States)

    Lehrer, Paul M.; Gevirtz, Richard

    2014-01-01

    In recent years there has been substantial support for heart rate variability biofeedback (HRVB) as a treatment for a variety of disorders and for performance enhancement (Gevirtz, 2013). Since conditions as widely varied as asthma and depression seem to respond to this form of cardiorespiratory feedback training, the issue of possible mechanisms becomes more salient. The most supported possible mechanism is the strengthening of homeostasis in the baroreceptor (Vaschillo et al., 2002; Lehrer et al., 2003). Recently, the effect on the vagal afferent pathway to the frontal cortical areas has been proposed. In this article, we review these and other possible mechanisms that might explain the positive effects of HRVB. PMID:25101026

  15. Heart rate variability biofeedback: How and why does it work?

    Directory of Open Access Journals (Sweden)

    Paul M Lehrer

    2014-07-01

    Full Text Available In recent years there has been substantial support for Heart Rate Variability Biofeedback (HRVB as a treatment for a variety of disorders and for performance enhancement (Gevirtz, 2013. Since conditions as widely varied as asthma and depression seem to respond to this form of cardiorespiratory feedback training, the issue of possible mechanisms becomes more salient. The most supported possible mechanism is the strengthening of homeostasis in the barorecptor (Vashillo, et al, 2002; Lehrer, et al, 2003. Recently, the effect on the vagal afferent pathway to the frontal cortical areas has been proposed. In this article, we review these and other possible mechanisms that might explain the positive effects of HRVB.

  16. Le Chatelier's principle with multiple relaxation channels

    Science.gov (United States)

    Gilmore, R.; Levine, R. D.

    1986-05-01

    Le Chatelier's principle is discussed within the constrained variational approach to thermodynamics. The formulation is general enough to encompass systems not in thermal (or chemical) equilibrium. Particular attention is given to systems with multiple constraints which can be relaxed. The moderation of the initial perturbation increases as additional constraints are removed. This result is studied in particular when the (coupled) relaxation channels have widely different time scales. A series of inequalities is derived which describes the successive moderation as each successive relaxation channel opens up. These inequalities are interpreted within the metric-geometry representation of thermodynamics.

  17. The internal-external respiratory motion correlation is unaffected by audiovisual biofeedback.

    Science.gov (United States)

    Steel, Harry; Pollock, Sean; Lee, Danny; Keall, Paul; Kim, Taeho

    2014-03-01

    This study evaluated if an audiovisual (AV) biofeedback causes variation in the level of external and internal correlation due to its interactive intervention in natural breathing. The internal (diaphragm) and external (abdominal wall) respiratory motion signals of 15 healthy human subjects under AV biofeedback and free breathing (FB) were analyzed and measures of correlation and regularity taken. Regularity metrics (root mean square error and spectral power dispersion metric) were obtained and the correlation between these metrics and the internal and external correlation was investigated. For FB and AV biofeedback assisted breathing the mean correlations found between internal and external respiratory motion were 0.96±0.02 and 0.96±0.03, respectively. This means there is no evidence to suggest (p-value=0.88) any difference in the correlation between internal and external respiratory motion with the use of AV biofeedback. Our results confirmed the hypothesis that the internal-external correlation with AV biofeedback is the same as for free breathing. Should this correlation be maintained for patients, AV biofeedback can be implemented in the clinic with confidence as regularity improvements using AV biofeedback with an external signal will be reflected in increased internal motion regularity.

  18. Biofeedback on heart rate variability in cardiac rehabilitation: practical feasibility and psycho-physiological effects.

    Science.gov (United States)

    Climov, Daniela; Lysy, Camille; Berteau, Sylvain; Dutrannois, Jacques; Dereppe, Hubert; Brohet, Christian; Melin, Jacques

    2014-06-01

    Biofeedback is a self-regulation therapy by which the patient learns how to optimize the functioning of his autonomic nervous system. It has been applied to patients with various cardiovascular disorders. The purpose of this study was to investigate the practical feasibility and the psychophysiological effects of biofeedback applied to heart rate variability (HRV biofeedback) in order to increase cardiac coherence in coronary artery disease (CAD) patients participating in a cardiac rehabilitation programme. In this randomised and controlled study, 31 CAD patients were randomly assigned to an experimental or to a control group. The experimental group participated in a programme of 10 sessions of cardiac coherence biofeedback training, in addition to the rehabilitation programme. The control group participated in the usual cardiac rehabilitation programme only. Physiological variables (systolic and diastolic blood pressure, SDNN) and psychosocial variables (anxiety, depression, type D personality) were measured at the start and at the end of the programme in both groups. Statistical comparisons assessed the inter and intra group differences. The small sample size precludes any firm conclusions concerning the effect of cardiac coherence biofeedback on physiological or psychological variables. However, we observed a significant increase of the percentage of cardiac coherence, in relation with an increased SDNN index. Our study demonstrated the practical feasibility of cardiac coherence biofeedback training in CAD patients. Further research is desirable to investigate the potential benefit of cardiac coherence biofeedback as an adjunct to stress management in cardiac rehabilitation.

  19. [Biofeedback and drug-resistant epilepsy: back to an earlier treatment?].

    Science.gov (United States)

    Micoulaud-Franchi, J A; Lanteaume, L; Pallanca, O; Vion-Dury, J; Bartolomei, F

    2014-03-01

    Biofeedback is a complementary non-pharmacological and non-surgical therapeutic developed over the last thirty years in the management of drug-resistant epilepsy. Biofeedback allows learning cognitive and behavioral strategies via a psychophysiological feedback loop. Firstly, this paper describes the different types of biofeedback protocols used for the treatment of drug-refractory epilepsy and their physiological justifications. Secondly, this paper analyzes the evidence of effectiveness, from a medical point of view, on reducing the numbers of seizures, and from a neurophysiological point of view, on the changing brain activity. Electroencephalography (EEG) biofeedback (neurofeedback) protocol on sensorimotor rhythms (SMR) has been investigated in many studies, the main limitation being small sample sizes and lack of control groups. The newer neurofeedback protocol on slow cortical potential (SCP) and galvanic skin response (GSR) biofeedback protocols have been used in a smaller number of studies. But, these studies are more rigorous with larger sized samples, matched control groups, and attempts to control the placebo effect. These protocols also open the way for innovative neurophysiological researches and may predict a renewal of biofeedback techniques. Biofeedback would have legitimacy in the field of clinical drug-resistant epilepsy at the interface between therapeutic and clinical neurophysiology. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

  20. Ultrasound biofeedback treatment for persisting childhood apraxia of speech.

    Science.gov (United States)

    Preston, Jonathan L; Brick, Nickole; Landi, Nicole

    2013-11-01

    The purpose of this study was to evaluate the efficacy of a treatment program that includes ultrasound biofeedback for children with persisting speech sound errors associated with childhood apraxia of speech (CAS). Six children ages 9-15 years participated in a multiple baseline experiment for 18 treatment sessions during which treatment focused on producing sequences involving lingual sounds. Children were cued to modify their tongue movements using visual feedback from real-time ultrasound images. Probe data were collected before, during, and after treatment to assess word-level accuracy for treated and untreated sound sequences. As participants reached preestablished performance criteria, new sequences were introduced into treatment. All participants met the performance criterion (80% accuracy for 2 consecutive sessions) on at least 2 treated sound sequences. Across the 6 participants, performance criterion was met for 23 of 31 treated sequences in an average of 5 sessions. Some participants showed no improvement in untreated sequences, whereas others showed generalization to untreated sequences that were phonetically similar to the treated sequences. Most gains were maintained 2 months after the end of treatment. The percentage of phonemes correct increased significantly from pretreatment to the 2-month follow-up. A treatment program including ultrasound biofeedback is a viable option for improving speech sound accuracy in children with persisting speech sound errors associated with CAS.

  1. Business model design for a wearable biofeedback system.

    Science.gov (United States)

    Hidefjäll, Patrik; Titkova, Dina

    2015-01-01

    Wearable sensor technologies used to track daily activities have become successful in the consumer market. In order for wearable sensor technology to offer added value in the more challenging areas of stress-rehab care and occupational health stress-related biofeedback parameters need to be monitored and more elaborate business models are needed. To identify probable success factors for a wearable biofeedback system (Affective Health) in the two mentioned market segments in a Swedish setting, we conducted literature studies and interviews with relevant representatives. Data were collected and used first to describe the two market segments and then to define likely feasible business model designs, according to the Business Model Canvas framework. Needs of stakeholders were identified as inputs to business model design. Value propositions, a key building block of a business model, were defined for each segment. The value proposition for occupational health was defined as "A tool that can both identify employees at risk of stress-related disorders and reinforce healthy sustainable behavior" and for healthcare as: "Providing therapists with objective data about the patient's emotional state and motivating patients to better engage in the treatment process".

  2. The Mozart effect in biofeedback visual rehabilitation: a case report.

    Science.gov (United States)

    Salvatore, Serena; Librando, Aloisa; Esposito, Mariacristina; Vingolo, Enzo M

    2011-01-01

    To evaluate the usefulness of acoustic biofeedback by means of Mozart's Sonata for Two Pianos in D Major K. 448 to maintain and/or restore visual performance in a patient with macular pucker and glaucoma. A 74-year-old patient with open angle glaucoma in both eyes and macular pucker in the right eye (RE) underwent visual rehabilitation with acoustic biofeedback by means of the MAIA™ Vision Training Module (Centervue, Padova, Italy) 10 minutes each eye once a week for 5 weeks. The patient was asked to move his eyes according to a sound which changed into Mozart's Sonata for Two Pianos when the patient locked the fixation target. Best-corrected visual acuity improved in his right eye (RE) and was stable in the left eye (LE). Fixation stability improved in both eyes, and retinal sensitivity decreased in the RE and improved in the LE. The characteristic of the macular pucker did not change during the training as demonstrated with optical coherence tomography. The patient was very satisfied with the training, as demonstrated by a 25-item questionnaire (National Eye Institute - Visual Functioning Questionnaire, NEI-VFQ-25). The patient's reading speed and the character size which he was able to read improved in his RE. Music could enhance synaptic plasticity and affect neural learning and fixation training by means of MAIA vision training. Therefore it can improve visual performance in patients with macular pucker, postpone the surgical time, and assure a better quality of life for the patient.

  3. 3Mo: A model for music-based biofeedback

    Directory of Open Access Journals (Sweden)

    Pieter-Jan Maes

    2016-12-01

    Full Text Available In the domain of sports and motor rehabilitation, it is of major importance to regulate and control physiological processes and physical motion in most optimal ways. For that purpose, real-time auditory feedback of physiological and physical information based on sound signals, often termed `sonification’, has been proven particularly useful. However, the use of music in biofeedback systems has been much less explored. In the current article, we assert that the use of music, and musical principles, can have a major added value, with respect to mere sound signals, to the benefit of psychological and physical optimization of sports and motor rehabilitation tasks. In this article, we present the 3Mo model to describe three main functions of music that contribute to these benefits. These functions relate the power of music to Motivate, and to Monitor and Modify physiological and physical processes. The model brings together concepts and theories related to human sensorimotor interaction with music, and specifies the underlying psychological and physiological principles. This 3Mo model is intended to provide a conceptual framework that guides future research on musical biofeedback systems in the domain of sports and motor rehabilitation.

  4. 3Mo: A Model for Music-Based Biofeedback.

    Science.gov (United States)

    Maes, Pieter-Jan; Buhmann, Jeska; Leman, Marc

    2016-01-01

    In the domain of sports and motor rehabilitation, it is of major importance to regulate and control physiological processes and physical motion in most optimal ways. For that purpose, real-time auditory feedback of physiological and physical information based on sound signals, often termed "sonification," has been proven particularly useful. However, the use of music in biofeedback systems has been much less explored. In the current article, we assert that the use of music, and musical principles, can have a major added value, on top of mere sound signals, to the benefit of psychological and physical optimization of sports and motor rehabilitation tasks. In this article, we present the 3Mo model to describe three main functions of music that contribute to these benefits. These functions relate the power of music to Motivate, and to Monitor and Modify physiological and physical processes. The model brings together concepts and theories related to human sensorimotor interaction with music, and specifies the underlying psychological and physiological principles. This 3Mo model is intended to provide a conceptual framework that guides future research on musical biofeedback systems in the domain of sports and motor rehabilitation.

  5. The influence of biofeedback training on trapezius activity and rest during occupational computer work

    DEFF Research Database (Denmark)

    Holtermann, A; Søgaard, K; Christensen, H

    2008-01-01

    The aim of this study was to investigate effects of biofeedback training on trapezius activity and rest (gaps) during occupational computer work. A randomized controlled trial with 164 computer workers was performed. Two groups working with computer mouse more than 50% (n = 64) and less than 25% (n....... By improving trapezius inactivity during computer work, biofeedback training may have the potential to prevent trapezius myalgia in computer workers....... muscles during normal computer work was recorded. Changes in discomfort/pain were not recorded. The biofeedback training reduced activity (P

  6. Rehabilitation of balance-impaired stroke patients through audio-visual biofeedback

    DEFF Research Database (Denmark)

    Gheorghe, Cristina; Nissen, Thomas; Juul Rosengreen Christensen, Daniel

    2015-01-01

    This study explored how audio-visual biofeedback influences physical balance of seven balance-impaired stroke patients, between 33–70 years-of-age. The setup included a bespoke balance board and a music rhythm game. The procedure was designed as follows: (1) a control group who performed a balance...... training exercise without any technological input, (2) a visual biofeedback group, performing via visual input, and (3) an audio-visual biofeedback group, performing via audio and visual input. Results retrieved from comparisons between the data sets (2) and (3) suggested superior postural stability...

  7. Differential Effects of Visual-Acoustic Biofeedback Intervention for Residual Speech Errors

    Science.gov (United States)

    McAllister Byun, Tara; Campbell, Heather

    2016-01-01

    Recent evidence suggests that the incorporation of visual biofeedback technologies may enhance response to treatment in individuals with residual speech errors. However, there is a need for controlled research systematically comparing biofeedback versus non-biofeedback intervention approaches. This study implemented a single-subject experimental design with a crossover component to investigate the relative efficacy of visual-acoustic biofeedback and traditional articulatory treatment for residual rhotic errors. Eleven child/adolescent participants received ten sessions of visual-acoustic biofeedback and 10 sessions of traditional treatment, with the order of biofeedback and traditional phases counterbalanced across participants. Probe measures eliciting untreated rhotic words were administered in at least three sessions prior to the start of treatment (baseline), between the two treatment phases (midpoint), and after treatment ended (maintenance), as well as before and after each treatment session. Perceptual accuracy of rhotic production was assessed by outside listeners in a blinded, randomized fashion. Results were analyzed using a combination of visual inspection of treatment trajectories, individual effect sizes, and logistic mixed-effects regression. Effect sizes and visual inspection revealed that participants could be divided into categories of strong responders (n = 4), mixed/moderate responders (n = 3), and non-responders (n = 4). Individual results did not reveal a reliable pattern of stronger performance in biofeedback versus traditional blocks, or vice versa. Moreover, biofeedback versus traditional treatment was not a significant predictor of accuracy in the logistic mixed-effects model examining all within-treatment word probes. However, the interaction between treatment condition and treatment order was significant: biofeedback was more effective than traditional treatment in the first phase of treatment, and traditional treatment was more effective

  8. Universal relaxation times for electron and nucleon gases

    OpenAIRE

    Pelc, M.; Marciak-Kozlowska, J.; Kozlowski, M.

    2007-01-01

    In this paper we calculate the universal relaxation times for electron and nucleon fermionic gases. We argue that the universal relaxation time tau(i) is equal tau(i)=h/m square v(i) where v(i)=alpha(i)c and alpha(1)=0.15 for nucleon gas and alpha(2)=1/137 for electron gas, c=light velocity. With the universal relaxation time we formulate the thermal Proca equation for fermionic gases. Key words: universal relaxation time, thermal universal Proca equation.

  9. Biofeedback no tratamento de transtornos relacionados ao estresse e à ansiedade: uma revisão crítica Biofeedback en el tratamiento de trastornos relacionados con el estrés y la ansiedad: una revisión crítica Biofeedback in the treatment of stress and anxiety-related disorders: a critical review

    Directory of Open Access Journals (Sweden)

    Ricardo da Costa Padovani

    2013-04-01

    Full Text Available O treinamento em biofeedback tem sido utilizado para o tratamento de diferentes quadros clínicos e para a prevenção/alívio de sintomas relacionados ao estresse/ansiedade. Este trabalho analisou a literatura de 2008 a 2012 sobre o tema "biofeedback, estresse e ansiedade" publicada nas bases MEDLINE, LILACS e Web of Sciences, utilizando como palavras-chave "biofeedback", "anxiety", "stress", "psychology" e "biofeedback training". Os resultados demonstram que técnicas de biofeedback são eficazes no manejo do estresse/ansiedade nas diferentes populações estudadas. Entretanto, todos os estudos encontrados foram realizados fora do Brasil, o que sugere que técnicas de biofeedback como ferramenta terapêutica não tem sido utilizadas no país, por algum motivo que merece ser melhor investigado.El entrenamiento con biofeedback se ha utilizado para el tratamiento de diferentes manifestaciones clínicas y para la prevención y alivio de síntomas relacionados con el estrés/ansiedad. Este estudio analizó la literatura desde 2008 hasta 2012 sobre el tema "biofeedback, estrés y ansiedad", publicada en MEDLINE, LILACS y Web of Sciences, utilizando como palabras clave "biofeedback", "anxiety", "stress", "psychology" y "biofeedback training". Los resultados demuestran que técnicas de biofeedback son eficaces para el tratamiento del estrés y la ansiedad en diferentes poblaciones. Sin embargo, todos los estudios encontrados se realizaron fuera de Brasil, un indicador de que el biofeedback como herramienta terapéutica no ha sido utilizado en el país por una razón que debe investigarse más a fondo.Biofeedback training has been utilized for the treatment of different pathological conditions, in particular those related to stress/anxiety. This study reviews the scientific literature from 2008 to 2012 about the subject "biofeedback, stress and anxiety", published in MEDLINE, LILACS and Web of Sciences, using as keywords "biofeedback", "anxiety

  10. Mechanical relaxation in glasses

    International Nuclear Information System (INIS)

    Hiki, Y.

    2004-01-01

    The basic properties of glasses and the characteristics of mechanical relaxation in glasses were briefly reviewed, and then our studies concerned were presented. Experimental methods adopted were viscosity, internal friction, ultrasonic attenuation, and Brillouin scattering measurements. The specimens used were several kinds of inorganic, organic, and metallic glasses. The measurements were mainly carried out from the room temperature up to the glass transition temperature, and the relaxation time was determined as a function of temperature. The 'double relaxation' composed of two Arrhenius-type relaxations was observed in many materials. In both relaxations, the 'compensation effect' showing a correlation of the pre-exponential factor and the activation energy was observed. These results were explained by considering the 'complex relaxation' due to cooperative motions of atoms or group of atoms. Values of activation energy near the glass transition determined by the various experimental methods were compared with each other

  11. Biofeedback, cognitive-behavioral methods, and hypnosis in dermatology: is it all in your mind?

    Science.gov (United States)

    Shenefelt, Philip D

    2003-01-01

    Biofeedback can improve cutaneous problems that have an autonomic nervous system component. Examples include biofeedback of galvanic skin resistance (GSR) for hyperhidrosis and biofeedback of skin temperature for Raynaud's disease. Hypnosis may enhance the effects obtained by biofeedback. Cognitive-behavioral methods may resolve dysfunctional thought patterns (cognitive) or actions (behavioral) that damage the skin or interfere with dermatologic therapy. Responsive diseases include acne excoriée, atopic dermatitis, factitious cheilitis, hyperhidrosis, lichen simplex chronicus, needle phobia, neurodermatitis, onychotillomania, prurigo nodularis, trichotillomania, and urticaria. Hypnosis can facilitate aversive therapy and enhance desensitization and other cognitive-behavioral methods. Hypnosis may improve or resolve numerous dermatoses. Examples include acne excoriée, alopecia areata, atopic dermatitis, congenital ichthyosiform erythroderma, dyshidrotic dermatitis, erythromelalgia, furuncles, glossodynia, herpes simplex, hyperhidrosis, ichthyosis vulgaris, lichen planus, neurodermatitis, nummular dermatitis, postherpetic neuralgia, pruritus, psoriasis, rosacea, trichotillomania, urticaria, verruca vulgaris, and vitiligo. Hypnosis can also reduce the anxiety and pain associated with dermatologic procedures.

  12. ANMS-ESNM position paper and consensus guidelines on biofeedback therapy for anorectal disorders

    NARCIS (Netherlands)

    Rao, S. S. C.; Benninga, M. A.; Bharucha, A. E.; Chiarioni, G.; Di Lorenzo, C.; Whitehead, W. E.

    2015-01-01

    Anorectal disorders such as dyssynergic defecation, fecal incontinence, levator ani syndrome, and solitary rectal ulcer syndrome are common, and affect both the adult and pediatric populations. Although they are treated with several treatment approaches, over the last two decades, biofeedback

  13. A Wearable Respiratory Biofeedback System Based on Generalized Body Sensor Network

    Science.gov (United States)

    Liu, Guan-Zheng; Huang, Bang-Yu

    2011-01-01

    Abstract Wearable medical devices have enabled unobtrusive monitoring of vital signs and emerging biofeedback services in a pervasive manner. This article describes a wearable respiratory biofeedback system based on a generalized body sensor network (BSN) platform. The compact BSN platform was tailored for the strong requirements of overall system optimizations. A waist-worn biofeedback device was designed using the BSN. Extensive bench tests have shown that the generalized BSN worked as intended. In-situ experiments with 22 subjects indicated that the biofeedback device was discreet, easy to wear, and capable of offering wearable respiratory trainings. Pilot studies on wearable training patterns and resultant heart rate variability suggested that paced respirations at abdominal level and with identical inhaling/exhaling ratio were more appropriate for decreasing sympathetic arousal and increasing parasympathetic activities. PMID:21545293

  14. The role of biofeedback in the rehabilitation of veno-occlusive erectile dysfunction

    Directory of Open Access Journals (Sweden)

    Mohamed R Al-Helow

    2014-01-01

    Conclusion Pelviperineal muscles′ visual pressure biofeedback rehabilitation is effective, inexpensive, noninvasive, safe, and easily applicable in the treatment of venogenic ED and does not have as much side effects as medication.

  15. BIOFEEDBACK AS A METHOD FOR STUDENTS’ MENTAL STATE ASSESSMENT

    Directory of Open Access Journals (Sweden)

    M. Yu. Ababkova

    2017-01-01

    Full Text Available Introduction. Neurotechnologies based on the principles of a nervous system functioning are being introduced into modern educational process more and more actively. Neurotechnology-based devices give the chance to develop new educational products; to enlarge the content of education by means of transition from text, graphic and sound content filling of educational process to use of tactile, motor, emotional, and other content. One of the most perspective neurotechnologies for the field of education is the method of biofeedback (BF which enables to define students’ mental state, change various physiological processes proceeding from the obtained data, correct educational process, and improve its quality and effectiveness.The aim of the present publication is to identify the opportunities of the biofeedback method application for educational purposes.Methodology and research methods. A pilot study on the basis of biofeedback technique was conducted in order to study the influence of active learning methods on students’ mental state mastering in specialty “Advertising and Public Relations”. H. Eysenck’s PEN Model was used to form focus-groups (control and experimental; psychophysiological technique CMS (Current Mental State was applied for results processing. Also, such methods as comparative analysis, induction and generalization were used.Results. A true picture of psychological attributes of students’ mental condition has been received for efficient studying of the current psychological state on psychophysiological functions, and training active methods impact on a condition of mentality of students according to the results of cardiorhythmogram.The main results of a pilot research were quantitative data (as percentage points of the current mental and psychological conditions of examinees. The obtained results have reflected the degree of attributes manifestation such as general adaptive resource, degree of mobility (lability of

  16. Relaxation processes during amorphous metal alloys heating

    International Nuclear Information System (INIS)

    Malinochka, E.Ya.; Durachenko, A.M.; Borisov, V.T.

    1982-01-01

    Behaviour of Te+15 at.%Ge and Fe+13 at.%P+7 at.%C amorphous metal alloys during heating has been studied using the method of differential scanning calorimetry (DSC) as the most convenient one for determination of the value of heat effects, activation energies, temperature ranges of relaxation processes. Thermal effects corresponding to high-temperature relaxation processes taking place during amorphous metal alloys (AMA) heating are detected. The change of ratio of relaxation peaks values on DSC curves as a result of AMA heat treatment can be explained by the presence of a number of levels of inner energy in amorphous system, separated with potential barriers, the heights of which correspond to certain activation energies of relaxation processes

  17. The effect of biofeedback therapy on dyssynergic constipation in patients with or without Irritable Bowel Syndrome

    OpenAIRE

    Tannaz Ahadi; Faezeh Madjlesi; Bahar Mahjoubi; Rezvan Mirzaei; Bijan Forogh; Seyedeh Somayeh Daliri; Seyed Majid Derakhshandeh; Roxana Bazaz Behbahani; G Reza Raissi

    2014-01-01

    Background: The Rome II and III diagnostic criteria for dyssynergic defecation recommended the exclusion of irritable bowel syndrome (IBS). This study determined the effect of biofeedback therapy on dyssynergic constipation in patients with or without IBS. Materials and Methods: This study was a nonrandomized, single blinded, semi experimental study. Dyssynergic defecation patients with and without IBS were asked to undergo biofeedback therapy 8 sessions. The defecation dynamics and balloon e...

  18. Randomised controlled trial of biofeedback training in persistent encopresis with anismus

    OpenAIRE

    Nolan, T.; Catto-Smith, T.; Coffey, C.; Wells, J.

    1998-01-01

    BACKGROUND—Paradoxical external anal sphincter contraction during attempted defecation (anismus) is thought to be an important contributor to chronic faecal retention and encopresis in children. Biofeedback training can be used to teach children to abolish this abnormal contraction.
METHODS—A randomised controlled trial in medical treatment resistant and/or treatment dependent children with anismus using surface electromyographic (EMG) biofeedback training to determine wh...

  19. Relaxation characteristics of hastelloy X

    International Nuclear Information System (INIS)

    Suzuki, Kazuhiko

    1980-02-01

    Relaxation diagrams of Hastelloy X (relaxation curves, relaxation design diagrams, etc.) were generated from the creep constitutive equation of Hastelloy X, using inelastic stress analysis code TEPICC-J. These data are in good agreement with experimental relaxation data of ORNL-5479. Three typical inelastic stress analyses were performed for various relaxation behaviors of the high-temperature structures. An attempt was also made to predict these relaxation behaviors by the relaxation curves. (author)

  20. Audiovisual biofeedback improves image quality and reduces scan time for respiratory-gated 3D MRI

    Science.gov (United States)

    Lee, D.; Greer, P. B.; Arm, J.; Keall, P.; Kim, T.

    2014-03-01

    The purpose of this study was to test the hypothesis that audiovisual (AV) biofeedback can improve image quality and reduce scan time for respiratory-gated 3D thoracic MRI. For five healthy human subjects respiratory motion guidance in MR scans was provided using an AV biofeedback system, utilizing real-time respiratory motion signals. To investigate the improvement of respiratory-gated 3D MR images between free breathing (FB) and AV biofeedback (AV), each subject underwent two imaging sessions. Respiratory-related motion artifacts and imaging time were qualitatively evaluated in addition to the reproducibility of external (abdominal) motion. In the results, 3D MR images in AV biofeedback showed more anatomic information such as a clear distinction of diaphragm, lung lobes and sharper organ boundaries. The scan time was reduced from 401±215 s in FB to 334±94 s in AV (p-value 0.36). The root mean square variation of the displacement and period of the abdominal motion was reduced from 0.4±0.22 cm and 2.8±2.5 s in FB to 0.1±0.15 cm and 0.9±1.3 s in AV (p-value of displacement audiovisual biofeedback improves image quality and reduces scan time for respiratory-gated 3D MRI. These results suggest that AV biofeedback has the potential to be a useful motion management tool in medical imaging and radiation therapy procedures.

  1. Efficacy of Alfa EEG wave biofeedback in the management of anxiety

    Directory of Open Access Journals (Sweden)

    Pookala Bhat

    2010-01-01

    Full Text Available Background: Biofeedback is a technique in which people are trained to improve their health by learning to control certain internal bodily processes that normally occur involuntarily. Various studies in the past have shown usefulness of Alfa electroencephalographic (EEG biofeedback in the alleviation of anxiety symptoms. Though most of the psychiatric centers in the armed forces have this facility, not much work has been done in our setup to assess its efficacy in the management of anxiety. Hence this study was undertaken. Materials and Methods: This study was carried out in a multispecialty Command Hospital by enrolling 100 patients with psychiatric diagnosis from both inpatient and outpatient services. The anxiety level was assessed clinically and by using Hamilton Anxiety Scale and Taylor′s Manifest Anxiety Scale. One group of 50 patients was treated with Alfa EEG biofeedback sessions only, 5 times in a week for 8 weeks, along with specific pharmacotherapy. The other group was treated with appropriate dose of anxiolytics. The anxiety level was reassessed after 4 weeks and 8 weeks. Results: The response was better for mixed anxiety and depressive disorder with pharmacotherapy than with the biofeedback, but female patients showed better response with EEG biofeedback. Conclusion: In the short term, Alfa EEG biofeedback therapy is almost as efficacious as pharmacological intervention in the management of anxiety symptoms, and relatively more useful in females.

  2. Enhancing Intervention for Residual Rhotic Errors Via App-Delivered Biofeedback: A Case Study.

    Science.gov (United States)

    Byun, Tara McAllister; Campbell, Heather; Carey, Helen; Liang, Wendy; Park, Tae Hong; Svirsky, Mario

    2017-06-22

    Recent research suggests that visual-acoustic biofeedback can be an effective treatment for residual speech errors, but adoption remains limited due to barriers including high cost and lack of familiarity with the technology. This case study reports results from the first participant to complete a course of visual-acoustic biofeedback using a not-for-profit iOS app, Speech Therapist's App for /r/ Treatment. App-based biofeedback treatment for rhotic misarticulation was provided in weekly 30-min sessions for 20 weeks. Within-treatment progress was documented using clinician perceptual ratings and acoustic measures. Generalization gains were assessed using acoustic measures of word probes elicited during baseline, treatment, and maintenance sessions. Both clinician ratings and acoustic measures indicated that the participant significantly improved her rhotic production accuracy in trials elicited during treatment sessions. However, these gains did not transfer to generalization probes. This study provides a proof-of-concept demonstration that app-based biofeedback is a viable alternative to costlier dedicated systems. Generalization of gains to contexts without biofeedback remains a challenge that requires further study. App-delivered biofeedback could enable clinician-research partnerships that would strengthen the evidence base while providing enhanced treatment for children with residual rhotic errors. https://doi.org/10.23641/asha.5116318.

  3. The effects of heart rate variability biofeedback in patients with preterm labour.

    Science.gov (United States)

    Siepmann, Martin; Hennig, Una-Dorothea; Siepmann, Timo; Nitzsche, Katharina; Mück-Weymann, Michael; Petrowski, Katja; Weidner, Kerstin

    2014-03-01

    Preterm birth is a highly prevalent phenomenon that was shown to be associated with mental stress during pregnancy (Rich-Edwards and Grizzard in Am J Obstet Gynecol 192(5 Suppl):S30-S35, 2005). We aimed to assess the effects of heart rate variability (HRV)-biofeedback in patients with preterm labour. Therefore, we conducted a controlled randomized parallel group study in 48 female patients aged 19-38 years (median = 29) with preterm labour at gestational week 24th-32nd (median = 29th). In this study, one group (n = 24) attended six sessions of HRV-biofeedback over 2 weeks whereas patients of the other group (n = 24) were assigned to control sessions. In the HRV-biofeedback treated group, perception of chronic stress was decreased 4 weeks after completion of training compared to baseline (p biofeedback group, preterm birth was seen in 3 patients (13 %) whereas in the control group, preterm delivery occurred in 8 patients (33 %, p = n.s.). There was no difference in birth weight between groups and HRV remained unchanged. In conclusion, our study demonstrates that HRV-biofeedback can reduce chronic stress in patients with preterm labour when administered as an adjunct to routine care. However, it remains unclear whether stress reduction through HRV-biofeedback has a beneficial effect on preterm birth.

  4. Breathing exercises with vagal biofeedback may benefit patients with functional dyspepsia.

    Science.gov (United States)

    Hjelland, Ina E; Svebak, Sven; Berstad, Arnold; Flatabø, Geir; Hausken, Trygve

    2007-09-01

    Many patients with functional dyspepsia (FD) have postprandial symptoms, impaired gastric accommodation and low vagal tone. The aim of this study was to improve vagal tone, and thereby also drinking capacity, intragastric volume and quality of life, using breathing exercises with vagal biofeedback. Forty FD patients were randomized to either a biofeedback group or a control group. The patients received similar information and care. Patients in the biofeedback group were trained in breathing exercises, 6 breaths/min, 5 min each day for 4 weeks, using specially designed software for vagal biofeedback. Effect variables included maximal drinking capacity using a drink test (Toro clear meat soup 100 ml/min), intragastric volume at maximal drinking capacity, respiratory sinus arrhythmia (RSA), skin conductance (SC) and dyspepsia-related quality of life scores. Drinking capacity and quality of life improved significantly more in the biofeedback group than in the control group (p=0.02 and p=0.01) without any significant change in baseline autonomic activity (RSA and SC) or intragastric volume. After the treatment period, RSA during breathing exercises was significantly correlated to drinking capacity (r=0.6, p=0.008). Breathing exercises with vagal biofeedback increased drinking capacity and improved quality of life in FD patients, but did not improve baseline vagal tone.

  5. A psychoengineering paradigm for the neurocognitive mechanisms of biofeedback and neurofeedback.

    Science.gov (United States)

    Gaume, A; Vialatte, A; Mora-Sánchez, A; Ramdani, C; Vialatte, F B

    2016-09-01

    We believe that the missing keystone to design effective and efficient biofeedback and neurofeedback protocols is a comprehensive model of the mechanisms of feedback learning. In this manuscript we review the learning models in behavioral, developmental and cognitive psychology, and derive a synthetic model of the psychological perspective on biofeedback. We afterwards review the neural correlates of feedback learning mechanisms, and present a general neuroscience model of biofeedback. We subsequently show how biomedical engineering principles can be applied to design efficient feedback protocols. We finally present an integrative psychoengineering model of the feedback learning processes, and provide new guidelines for the efficient design of biofeedback and neurofeedback protocols. We identify five key properties, (1) perceptibility=can the subject perceive the biosignal?, (2) autonomy=can the subject regulate by himself?, (3) mastery=degree of control over the biosignal, (4) motivation=rewards system of the biofeedback, and (5) learnability=possibility of learning. We conclude with guidelines for the investigation and promotion of these properties in biofeedback protocols. Copyright © 2016 Elsevier Ltd. All rights reserved.

  6. Effects of real-time gait biofeedback on paretic propulsion and gait biomechanics in individuals post-stroke.

    Science.gov (United States)

    Genthe, Katlin; Schenck, Christopher; Eicholtz, Steven; Zajac-Cox, Laura; Wolf, Steven; Kesar, Trisha M

    2018-04-01

    Objectives Gait training interventions that target paretic propulsion induce improvements in walking speed and function in individuals post-stroke. Previously, we demonstrated that able-bodied individuals increase propulsion unilaterally when provided real-time biofeedback targeting anterior ground reaction forces (AGRF). The purpose of this study was to, for the first time, investigate short-term effects of real-time AGRF gait biofeedback training on post-stroke gait. Methods Nine individuals with post-stroke hemiparesis (6 females, age = 54 ± 12.4 years 39.2 ± 24.4 months post-stroke) completed three 6-minute training bouts on an instrumented treadmill. During training, visual and auditory biofeedback were provided to increase paretic AGRF during terminal stance. Gait biomechanics were evaluated before training, and during retention tests conducted 2, 15, and 30 minutes post-training. Primary dependent variables were paretic and non-paretic peak AGRF; secondary variables included paretic and non-paretic peak trailing limb angle, plantarflexor moment, and step length. In addition to evaluating the effects of biofeedback training on these dependent variables, we compared effects of a 6-minute biofeedback training bout to a non-biofeedback control condition. Results Compared to pre-training, significantly greater paretic peak AGRFs were generated during the 2, 15, and 30-minute retention tests conducted after the 18-minute biofeedback training session. Biofeedback training induced no significant effects on the non-paretic leg. Comparison of a 6-minute biofeedback training bout with a speed-matched control bout without biofeedback demonstrated a main effect for training type, with greater peak AGRF generation during biofeedback. Discussion Our results suggest that AGRF biofeedback may be a feasible and promising gait training strategy to target propulsive deficits in individuals post-stroke.

  7. Biofeedback for foot offloading in diabetic patients with peripheral neuropathy.

    Science.gov (United States)

    Pataky, Z; de León Rodriguez, D; Allet, L; Golay, A; Assal, M; Assal, J-P; Hauert, C-A

    2010-01-01

    The reduction of high plantar pressure in diabetic patients with peripheral neuropathy is mandatory for prevention of foot ulcers and amputations. We used a new biofeedback-based method to reduce the plantar pressure at an at-risk area of foot in diabetic patients with peripheral neuropathy. Thirteen diabetic patients (age 60.8 +/- 12.3 years, body mass index 29.0 +/- 5.0 kg/m(2)) with peripheral neuropathy of the lower limbs were studied. Patients with memory impairment were excluded. The portable in-shoe foot pressure measurement system (PEDAR) was used for foot offloading training by biofeedback. The learning procedure consisted in sequences of walking (10 steps), each followed by a subjective estimation of performance and objective feedback. The goal was to achieve three consecutive walking cycles of 10 steps, with a minimum of seven steps inside the range of 40-80% of the baseline peak plantar pressure. The peak plantar pressure was assessed during the learning period and at retention tests. A significant difference in peak plantar pressure was recorded between the beginning and the end of the learning period (when the target for plantar pressure was achieved) (262 +/- 70 vs. 191 +/- 53 kPa; P = 0.002). The statistically significant difference between the beginning of learning and all retention tests persisted, even at the 10-day follow-up. Terminal augmented feedback training may positively affect motor learning in diabetic patients with peripheral neuropathy and could possibly lead to suitable foot offloading. Additional research is needed to confirm the maintenance of offloading in the long term.

  8. The Mozart effect in biofeedback visual rehabilitation: a case report

    Directory of Open Access Journals (Sweden)

    Salvatore S

    2011-09-01

    Full Text Available Serena Salvatore, Aloisa Librando, Mariacristina Esposito, Enzo M VingoloDepartment of Ophthalmology, University La Sapienza, Polo Pontino, Alfredo Fiorini Hospital, Terracina, ItalyPurpose: To evaluate the usefulness of acoustic biofeedback by means of Mozart’s Sonata for Two Pianos in D Major K. 448 to maintain and/or restore visual performance in a patient with macular pucker and glaucoma.Methods: A 74-year-old patient with open angle glaucoma in both eyes and macular pucker in the right eye (RE underwent visual rehabilitation with acoustic biofeedback by means of the MAIA™ Vision Training Module (Centervue, Padova, Italy 10 minutes each eye once a week for 5 weeks. The patient was asked to move his eyes according to a sound which changed into Mozart’s Sonata for Two Pianos when the patient locked the fixation target.Results: Best-corrected visual acuity improved in his right eye (RE and was stable in the left eye (LE. Fixation stability improved in both eyes, and retinal sensitivity decreased in the RE and improved in the LE. The characteristic of the macular pucker did not change during the training as demonstrated with optical coherence tomography. The patient was very satisfied with the training, as demonstrated by a 25-item questionnaire (National Eye Institute – Visual Functioning Questionnaire, NEI-VFQ-25. The patient’s reading speed and the character size which he was able to read improved in his RE.Conclusion: Music could enhance synaptic plasticity and affect neural learning and fixation training by means of MAIA vision training. Therefore it can improve visual performance in patients with macular pucker, postpone the surgical time, and assure a better quality of life for the patient.Keywords: glaucoma, macular cellophane, music, vision training

  9. TEACHING NEUROMUSCULAR RELAXATION.

    Science.gov (United States)

    NORRIS, JEANNE E.; STEINHAUS, ARTHUR H.

    THIS STUDY ATTEMPTED TO FIND OUT WHETHER (1) THE METHODS FOR ATTAINING NEUROMUSCULAR RELAXATION THAT HAVE PROVED FRUITFUL IN THE ONE-TO-ONE RELATIONSHIP OF THE CLINIC CAN BE SUCCESSFULLY ADAPTED TO THE TEACHER-CLASS RELATIONSHIP OF THE CLASSROOM AND GYMNASIUM, AND (2) NEUROMUSCULAR RELAXATION CAN BE TAUGHT SUCCESSFULLY BY AN APPROPRIATELY TRAINED…

  10. Relaxation techniques for stress

    Science.gov (United States)

    ... raise your heart rate. This is called the stress response. Relaxation techniques can help your body relax and lower your blood pressure ... also many other types of breathing techniques you can learn. In many cases, you do not need much ... including those that cause stress. Meditation has been practiced for thousands of years, ...

  11. Effects of Heart Rate Variability Biofeedback on EEG Alpha Asymmetry and Anxiety Symptoms in Male Athletes: A Pilot Study.

    Science.gov (United States)

    Dziembowska, Inga; Izdebski, Paweł; Rasmus, Anna; Brudny, Janina; Grzelczak, Marta; Cysewski, Piotr

    2016-06-01

    Heart rate variability biofeedback (HRV-BFB) has been shown as useful tool to manage stress in various populations. The present study was designed to investigate whether the biofeedback-based stress management tool consisting of rhythmic breathing, actively self-generated positive emotions and a portable biofeedback device induce changes in athletes' HRV, EEG patterns, and self-reported anxiety and self-esteem. The study involved 41 healthy male athletes, aged 16-21 (mean 18.34 ± 1.36) years. Participants were randomly divided into two groups: biofeedback and control. Athletes in the biofeedback group received HRV biofeedback training, athletes in the control group didn't receive any intervention. During the randomized controlled trial (days 0-21), the mean anxiety score declined significantly for the intervention group (change-4 p athletes in biofeedback group showed substantial and statistically significant improvement in heart rate variability indices and changes in power spectra of both theta and alpha brain waves, and alpha asymmetry. These changes suggest better self-control in the central nervous system and better flexibility of the autonomic nervous system in the group that received biofeedback training. A HRV biofeedback-based stress management tool may be beneficial for stress reduction for young male athletes.

  12. Pair plasma relaxation time scales.

    Science.gov (United States)

    Aksenov, A G; Ruffini, R; Vereshchagin, G V

    2010-04-01

    By numerically solving the relativistic Boltzmann equations, we compute the time scale for relaxation to thermal equilibrium for an optically thick electron-positron plasma with baryon loading. We focus on the time scales of electromagnetic interactions. The collisional integrals are obtained directly from the corresponding QED matrix elements. Thermalization time scales are computed for a wide range of values of both the total-energy density (over 10 orders of magnitude) and of the baryonic loading parameter (over 6 orders of magnitude). This also allows us to study such interesting limiting cases as the almost purely electron-positron plasma or electron-proton plasma as well as intermediate cases. These results appear to be important both for laboratory experiments aimed at generating optically thick pair plasmas as well as for astrophysical models in which electron-positron pair plasmas play a relevant role.

  13. Effects of unilateral real-time biofeedback on propulsive forces during gait.

    Science.gov (United States)

    Schenck, Christopher; Kesar, Trisha M

    2017-06-06

    In individuals with post-stroke hemiparesis, reduced push-off force generation in the paretic leg negatively impacts walking function. Gait training interventions that increase paretic push-off can improve walking function in individuals with neurologic impairment. During normal locomotion, push-off forces are modulated with variations in gait speed and slope. However, it is unknown whether able-bodied individuals can selectively modulate push-off forces from one leg in response to biofeedback. Here, in a group of young, neurologically-unimpaired individuals, we determined the effects of a real-time visual and auditory biofeedback gait training paradigm aimed at unilaterally increasing anteriorly-directed ground reaction force (AGRF) in the targeted leg. Ground reaction force data during were collected from 7 able-bodied individuals as they walked at a self-selected pace on a dual-belt treadmill instrumented with force platforms. During 11-min of gait training, study participants were provided real-time AGRF biofeedback encouraging a 20-30% increase in peak AGRF generated by their right (targeted) leg compared to their baseline (pre-training) AGRF. AGRF data were collected before, during, and after the biofeedback training period, as well as during two retention tests performed without biofeedback and after standing breaks. Compared to AGRFs generated during the pre-training gait trials, participants demonstrated a significantly greater AGRF in the targeted leg during and immediately after training, indicating that biofeedback training was successful at inducing increased AGRF production in the targeted leg. Additionally, participants continued to demonstrate greater AGRF production in the targeted leg after two standing breaks, showing short-term recall of the gait pattern learned during the biofeedback training. No significant effects of training were observed on the AGRF in the non-targeted limb, showing the specificity of the effects of biofeedback toward the

  14. SU-E-J-29: Audiovisual Biofeedback Improves Tumor Motion Consistency for Lung Cancer Patients

    International Nuclear Information System (INIS)

    Lee, D; Pollock, S; Makhija, K; Keall, P; Greer, P; Arm, J; Hunter, P; Kim, T

    2014-01-01

    Purpose: To investigate whether the breathing-guidance system: audiovisual (AV) biofeedback improves tumor motion consistency for lung cancer patients. This will minimize respiratory-induced tumor motion variations across cancer imaging and radiotherapy procedues. This is the first study to investigate the impact of respiratory guidance on tumor motion. Methods: Tumor motion consistency was investigated with five lung cancer patients (age: 55 to 64), who underwent a training session to get familiarized with AV biofeedback, followed by two MRI sessions across different dates (pre and mid treatment). During the training session in a CT room, two patient specific breathing patterns were obtained before (Breathing-Pattern-1) and after (Breathing-Pattern-2) training with AV biofeedback. In each MRI session, four MRI scans were performed to obtain 2D coronal and sagittal image datasets in free breathing (FB), and with AV biofeedback utilizing Breathing-Pattern-2. Image pixel values of 2D images after the normalization of 2D images per dataset and Gaussian filter per image were used to extract tumor motion using image pixel values. The tumor motion consistency of the superior-inferior (SI) direction was evaluated in terms of an average tumor motion range and period. Results: Audiovisual biofeedback improved tumor motion consistency by 60% (p value = 0.019) from 1.0±0.6 mm (FB) to 0.4±0.4 mm (AV) in SI motion range, and by 86% (p value < 0.001) from 0.7±0.6 s (FB) to 0.1±0.2 s (AV) in period. Conclusion: This study demonstrated that audiovisual biofeedback improves both breathing pattern and tumor motion consistency for lung cancer patients. These results suggest that AV biofeedback has the potential for facilitating reproducible tumor motion towards achieving more accurate medical imaging and radiation therapy procedures

  15. SU-E-J-29: Audiovisual Biofeedback Improves Tumor Motion Consistency for Lung Cancer Patients

    Energy Technology Data Exchange (ETDEWEB)

    Lee, D; Pollock, S; Makhija, K; Keall, P [The University of Sydney, Camperdown, NSW (Australia); Greer, P [The University of Newcastle, Newcastle, NSW (Australia); Calvary Mater Newcastle Hospital, Newcastle, NSW (Australia); Arm, J; Hunter, P [Calvary Mater Newcastle Hospital, Newcastle, NSW (Australia); Kim, T [The University of Sydney, Camperdown, NSW (Australia); University of Virginia Health System, Charlottesville, VA (United States)

    2014-06-01

    Purpose: To investigate whether the breathing-guidance system: audiovisual (AV) biofeedback improves tumor motion consistency for lung cancer patients. This will minimize respiratory-induced tumor motion variations across cancer imaging and radiotherapy procedues. This is the first study to investigate the impact of respiratory guidance on tumor motion. Methods: Tumor motion consistency was investigated with five lung cancer patients (age: 55 to 64), who underwent a training session to get familiarized with AV biofeedback, followed by two MRI sessions across different dates (pre and mid treatment). During the training session in a CT room, two patient specific breathing patterns were obtained before (Breathing-Pattern-1) and after (Breathing-Pattern-2) training with AV biofeedback. In each MRI session, four MRI scans were performed to obtain 2D coronal and sagittal image datasets in free breathing (FB), and with AV biofeedback utilizing Breathing-Pattern-2. Image pixel values of 2D images after the normalization of 2D images per dataset and Gaussian filter per image were used to extract tumor motion using image pixel values. The tumor motion consistency of the superior-inferior (SI) direction was evaluated in terms of an average tumor motion range and period. Results: Audiovisual biofeedback improved tumor motion consistency by 60% (p value = 0.019) from 1.0±0.6 mm (FB) to 0.4±0.4 mm (AV) in SI motion range, and by 86% (p value < 0.001) from 0.7±0.6 s (FB) to 0.1±0.2 s (AV) in period. Conclusion: This study demonstrated that audiovisual biofeedback improves both breathing pattern and tumor motion consistency for lung cancer patients. These results suggest that AV biofeedback has the potential for facilitating reproducible tumor motion towards achieving more accurate medical imaging and radiation therapy procedures.

  16. Can a four-session biofeedback regimen be used effectively for treating children with dysfunctional voiding?

    Science.gov (United States)

    Sener, Nevzat Can; Altunkol, Adem; Unal, Umut; Ercil, Hakan; Bas, Okan; Gumus, Kemal; Ciftci, Halil; Yeni, Ercan

    2015-01-01

    To compare the outcomes of the open-ended six to ten sessions of biofeedback against a novel regime of four sessions of biofeedback to treat children with dysfunctional voiding. Patients from two centers using different methods were retrospectively analyzed. Group 1 comprised 20 patients treated with four sessions of biofeedback. Group 2 comprised 20 patients treated with six to ten sessions of biofeedback. Each group was evaluated with subjective and objective parameters pre-treatment, immediately post-treatment and 6 months post-treatment. All patients in Group 1 were treated with four sessions of biofeedback and in Group 2 the mean number of sessions was 7.35±1.30 (range 6-10). Normalized voiding flow curves after treatment were determined in 18 patients in Group 1 (90%) and 19 patients in Group 2 (95%) (p=0.553). There were seven patients (35%) in Group 1 and eight patients (40%) in Group 2 with reflux. When units were compared, there were 11 units (4 bilateral) in Group 1 and 13 units (5 bilateral) in Group 2 with reflux (p=0.747). At 6 months post-treatment, in Group 1, seven had resolved (63.6%), three had improved (27.2%) and one persisted (9.01%). In Group 2, ten had resolved (76.9%) and three had improved (23.1%) (p=0.553). Biofeedback therapy is one of the most widely used techniques in dysfunctional voiding in children. The regime of use has not been well defined, and the results of this study showed that a regime of four sessions of biofeedback therapy may be as safe and effective as the previously defined open-ended six to ten sessions.

  17. Biofeedback interventions for people with cerebral palsy: a systematic review protocol.

    Science.gov (United States)

    MacIntosh, Alexander; Vignais, Nicolas; Biddiss, Elaine

    2017-01-13

    Cerebral palsy is a life-long disability that affects motor control and activities of daily living. Depending on the type of cerebral palsy, some individuals may have trouble performing tasks with one or both of their arms and/or legs. Different strategies exist to help develop motor capacity. Biofeedback therapy is a commonly applied rehabilitation strategy. In biofeedback therapy, information about the motor behavior while completing a task is given back to the individual to help improve their performance. This can provide valuable information that would otherwise be unknown to the individual. Biofeedback may also have a unique method of operation in clinical populations, such as people with cerebral palsy. Therefore, it is important to identify the most effective mechanisms for specific populations. This review aims to evaluate the effects of biofeedback interventions that have been used towards improving motor performance and motor learning in people with cerebral palsy. Using a customized strategy, MEDLINE, CINAHL, Embase, PsycINFO, Cochrane Central Register of Controlled Trials, SCOPUS, SPORTDiscus, and PEDro databases will be searched. Two independent reviewers will screen titles and abstracts, review full texts for inclusion criteria, and extract data from relevant articles using a standardized template. Quality of evidence and risk of bias will be assessed through the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) methodology. Several studies have investigated biofeedback-based interventions for people with cerebral palsy. However, there is a great variety and limited consensus regarding how to implement biofeedback mechanisms. This systematic review will consolidate the current evidence to direct future study and develop effective biofeedback rehabilitation strategies. PROSPERO ID: CRD42016047612.

  18. Relaxation strain measurements in cellular dislocation structures

    International Nuclear Information System (INIS)

    Tsai, C.Y.; Quesnel, D.J.

    1984-01-01

    The conventional picture of what happens during a stress relaxation usually involves imagining the response of a single dislocation to a steadily decreasing stress. The velocity of this dislocation decreases with decreasing stress in such a way that we can measure the stress dependence of the dislocation velocity. Analysis of the data from a different viewpoint enables us to calculate the apparent activation volume for the motion of the dislocation under the assumption of thermally activated glie. Conventional thinking about stress relaxation, however, does not consider the eventual fate of this dislocation. If the stress relaxes to a low enough level, it is clear that the dislocation must stop. This is consistent with the idea that we can determine the stress dependence of the dislocation velocity from relaxation data only for those cases where the dislocation's velocity is allowed to approach zero asymptotically, in short, for those cases where the dislocation never stops. This conflict poses a dilemma for the experimentalist. In real crystals, however, obstacles impede the dislocation's progress so that those dislocations which are stopped at a given stress will probably never resume motion under the influence of the steadily declining stress present during relaxation. Thus one could envision stress relaxation as a process of exhaustion of mobile dislocations, rather than a process of decreasing dislocation velocity. Clearly both points of view have merit and in reality both mechanisms contribute to the phenomena

  19. Audio-visual biofeedback for respiratory-gated radiotherapy: Impact of audio instruction and audio-visual biofeedback on respiratory-gated radiotherapy

    International Nuclear Information System (INIS)

    George, Rohini; Chung, Theodore D.; Vedam, Sastry S.; Ramakrishnan, Viswanathan; Mohan, Radhe; Weiss, Elisabeth; Keall, Paul J.

    2006-01-01

    Purpose: Respiratory gating is a commercially available technology for reducing the deleterious effects of motion during imaging and treatment. The efficacy of gating is dependent on the reproducibility within and between respiratory cycles during imaging and treatment. The aim of this study was to determine whether audio-visual biofeedback can improve respiratory reproducibility by decreasing residual motion and therefore increasing the accuracy of gated radiotherapy. Methods and Materials: A total of 331 respiratory traces were collected from 24 lung cancer patients. The protocol consisted of five breathing training sessions spaced about a week apart. Within each session the patients initially breathed without any instruction (free breathing), with audio instructions and with audio-visual biofeedback. Residual motion was quantified by the standard deviation of the respiratory signal within the gating window. Results: Audio-visual biofeedback significantly reduced residual motion compared with free breathing and audio instruction. Displacement-based gating has lower residual motion than phase-based gating. Little reduction in residual motion was found for duty cycles less than 30%; for duty cycles above 50% there was a sharp increase in residual motion. Conclusions: The efficiency and reproducibility of gating can be improved by: incorporating audio-visual biofeedback, using a 30-50% duty cycle, gating during exhalation, and using displacement-based gating

  20. Spin relaxation of iron in mixed state hemoproteins

    International Nuclear Information System (INIS)

    Wajnberg, E.; Kalinowski, H.J.; Bemski, G.; Helman, J.S.

    1984-01-01

    In pure states hemoproteins the relaxation of iron depends on its spin state. It is found that in both mixed state met-hemoglobin and met-myoglobin, the low and high spin states relax through an Orbach-like process. Also, very short (approx. 1 ns) and temperature independent transverse relaxation times T 2 were estimated. This peculiar behaviour of the relaxation may result from the unusual electronic structure of mixed state hemoproteins that allows thermal equilibrium and interconversion of the spin states. (Author) [pt

  1. Anomalous relaxation and self-organization in nonequilibrium processes

    International Nuclear Information System (INIS)

    Fatkullin, Ibrahim; Kladko, Konstantin; Mitkov, Igor; Bishop, A. R.

    2001-01-01

    We study thermal relaxation in ordered arrays of coupled nonlinear elements with external driving. We find that our model exhibits dynamic self-organization manifested in a universal stretched-exponential form of relaxation. We identify two types of self-organization, cooperative and anticooperative, which lead to fast and slow relaxation, respectively. We give a qualitative explanation for the behavior of the stretched exponent in different parameter ranges. We emphasize that this is a system exhibiting stretched-exponential relaxation without explicit disorder or frustration

  2. [Mind-body approach in the area of preventive medicine: focusing on relaxation and meditation for stress management].

    Science.gov (United States)

    Kang, Yunesik

    2010-09-01

    Emotional support and a stress management program should be simultaneously provided to clients as effective preventive services for healthy behavioral change. This study was conducted to review various relaxation and meditation intervention methods and their applicability for a preventive service program. The author of this paper tried to find various relaxation and meditation programs through a literature review and program searching and to introduce them. The 'Relaxation Response' and 'Mindfulness Based Stress Reduction (MBSR)' are the most the widely used meditative programs in mainstream medical systems. Abdominal breathing, Progressive Musclular Relaxation (PMR), Relaxative Imagery, Autogenic Training (AT) and Biofeedback are other well-known techniques for relaxation and stress management. I have developed and implemented some programs using these methods. Relaxation and meditation classes for cancer patients and a meditation based stress coping workshop are examples of this program. Relaxation and meditation seem to be good and effective methods for primary, secondary and tertiary preventive service programs. Program development and standardization and further study are needed for more and wider use of the mind-body approach in the preventive service area of medicine.

  3. Evaluation of HRV Biofeedback as a Resilience Building Reserve Component

    Science.gov (United States)

    2017-08-01

    introductory training in either HRV-BART or relaxation breathing alone and be assessed on baseline HRV and mental and physical health questionnaires...receive a 1.5-hour group introductory training in either HRV-BART or relaxation breathing alone and be assessed on baseline HRV and mental and physical...F., Furman, S. A., McCool, M. F., & Porges, S. W. (2012). Statistical strategies to quantify respiratory sinus arrhythmia: Are commonly used metrics

  4. Relaxation and kinetics in scalar field theories

    International Nuclear Information System (INIS)

    Boyanovsky, D.; Lawrie, I.D.; Lee, D.

    1996-01-01

    A new approach to the dynamics of relaxation and kinetics of thermalization in a scalar field theory is presented that incorporates the relevant time scales through the resummation of hard thermal loops. An alternative derivation of the kinetic equations for the open-quote open-quote quasiparticle close-quote close-quote distribution functions is obtained that allows a clear understanding of the different open-quote open-quote coarse-graining close-quote close-quote approximations usually involved in a kinetic description. This method leads to a systematic perturbative expansion to obtain the kinetic equations including hard thermal loop resummation and to an improvement including renormalization, off-shell effects, and contributions that change chemical equilibrium on short time scales. As a by-product of these methods we establish the equivalence between the relaxation time scale in the linearized equation of motion of the quasiparticles and the thermalization time scale of the quasiparticle distribution function in the open-quote open-quote relaxation time approximation close-quote close-quote including hard thermal loop effects. Hard thermal loop resummation dramatically modifies the scattering rate for long wavelength modes as compared to the usual (semi)classical estimate. Relaxation and kinetics are studied both in the unbroken and broken symmetry phases of the theory. The broken symmetry phase also provides the setting to obtain the contribution to the kinetic equations from processes that involve decay of a heavy scalar into light scalar particles in the medium. copyright 1996 The American Physical Society

  5. Audiovisual biofeedback improves the correlation between internal/external surrogate motion and lung tumor motion.

    Science.gov (United States)

    Lee, Danny; Greer, Peter B; Paganelli, Chiara; Ludbrook, Joanna Jane; Kim, Taeho; Keall, Paul

    2018-03-01

    Breathing management can reduce breath-to-breath (intrafraction) and day-by-day (interfraction) variability in breathing motion while utilizing the respiratory motion of internal and external surrogates for respiratory guidance. Audiovisual (AV) biofeedback, an interactive personalized breathing motion management system, has been developed to improve reproducibility of intra- and interfraction breathing motion. However, the assumption of the correlation of respiratory motion between surrogates and tumors is not always verified during medical imaging and radiation treatment. Therefore, the aim of the study was to test the hypothesis that the correlation of respiratory motion between surrogates and tumors is the same under free breathing without guidance (FB) and with AV biofeedback guidance for voluntary motion management. For 13 lung cancer patients receiving radiotherapy, 2D coronal and sagittal cine-MR images were acquired across two MRI sessions (pre- and mid-treatment) with two breathing conditions: (a) FB and (b) AV biofeedback, totaling 88 patient measurements. Simultaneously, the external respiratory motion of the abdomen was measured. The internal respiratory motion of the diaphragm and lung tumor was retrospectively measured from 2D coronal and sagittal cine-MR images. The correlation of respiratory motion between surrogates and tumors was calculated using Pearson's correlation coefficient for: (a) abdomen to tumor (abdomen-tumor) and (b) diaphragm to tumor (diaphragm-tumor). The correlations were compared between FB and AV biofeedback using several metrics: abdomen-tumor and diaphragm-tumor correlations with/without ≥5 mm tumor motion range and with/without adjusting for phase shifts between the signals. Compared to FB, AV biofeedback improved abdomen-tumor correlation by 11% (p = 0.12) from 0.53 to 0.59 and diaphragm-tumor correlation by 13% (p = 0.02) from 0.55 to 0.62. Compared to FB, AV biofeedback improved abdomen-tumor correlation by 17% (p = 0

  6. Assessment of the effectiveness of biofeedback in children with dyssynergic defecation and recalcitrant constipation/encopresis: does home biofeedback improve long-term outcomes.

    Science.gov (United States)

    Croffie, Joseph M; Ammar, M Samer; Pfefferkorn, Marian D; Horn, Debra; Klipsch, Ann; Fitzgerald, Joseph F; Gupta, Sandeep K; Molleston, Jean P; Corkins, Mark R

    2005-01-01

    The purpose of this study was to determine whether biofeedback benefits children with dyssynergic defecation and constipation/encopresis, and whether home biofeedback improves long-term outcomes. Thirty-six patients with chronic constipation who had failed at least 6 months of conventional treatment and demonstrated dyssynergic defecation at anorectal manometry were randomized to biofeedback in the laboratory alone (group 1, n=24) or in the laboratory and at home (group 2, n=12) and followed up at 2, 4, and a mean of 44 months. Thirty patients were available for long-term follow-up. Bowel movements increased in all from a mean of 1.4/week to 5.1, 5.8, and 5.1 per week at 2 months, 4 months, and long-term, respectively (p < or = 0.001). Soiling decreased in all from a mean of 5.5/week to 0.6, 0.1, and 1 per week at 2 months, 4 months, and long-term, respectively (p < or = 0.001). Laxative use decreased from a mean of 4.1 days/week to 0.6, 0.3, and 0.7 per week at 2 months, 4 months, and long-term, respectively (p < or = 0.001). Twenty-seven of 30 parents ranked their satisfaction a mean of 2.2 (range 1-excellent to 3-good). There were no significant differences in outcomes between the laboratory alone group and the laboratory plus home group. Biofeedback is beneficial for some children with chronic constipation and dyssynergic defecation. Supplemental home biofeedback does not improve long-term outcomes.

  7. Heart Rate Variability (HRV biofeedback: A new training approach for operator’s performance enhancement

    Directory of Open Access Journals (Sweden)

    Auditya Purwandini Sutarto

    2010-06-01

    Full Text Available The widespread implementation of advanced and complex systems requires predominantly operators’ cognitive functions and less importance of human manual control. On the other hand, most operators perform their cognitive functions below their peak cognitive capacity level due to fatigue, stress, and boredom. Thus, there is a need to improve their cognitive functions during work. The goal of this paper is to present a psychophysiology training approach derived from cardiovascular response named heart rate variability (HRV biofeedback. Description of resonant frequency biofeedback - a specific HRV training protocol - is discussed as well as its supported researches for the performance enhancement. HRV biofeedback training works by teaching people to recognize their involuntary HRV and to control patterns of this physiological response. The training is directed to increase HRV amplitude that promotes autonomic nervous system balance. This balance is associated with improved physiological functioning as well as psychological benefits. Most individuals can learn HRV biofeedback training easily which involves slowing the breathing rate (around six breaths/min to each individual’s resonant frequency at which the amplitude of HRV is maximized. Maximal control over HRV can be obtained in most people after approximately four sessions of training. Recent studies have demonstrated the effectiveness of HRV biofeedback to the improvement of some cognitive functions in both simulated and real industrial operators.

  8. Direct manipulation of physiological arousal in induced anxiety therapy - biofeedback approach.

    Science.gov (United States)

    Sappington, A A

    1977-10-01

    This study investigated the role of physiological arousal in the affect induction phase of Induced Anxiety therapy by using biofeedback to facilitate arousal. Twenty-one college students who were suffering from free-floating anxiety were assigned randomly to one of three groups: (1) a no-treatment control group simply completed the measures before and after therapy; (2) a conventional Induced Anxiety group went through five standard Induced Anxiety sessions; and (3) biofeedback Induced Anxiety group went through a similar procedure except that biofeedback was used in the affect induction phase to facilitate heart rate increase. It was found that the biofeedback procedure did result in a greater heart rate increase during the affect induction phase arousal than did the conventional procedure (.01 level of significance), but did not facilitate subjective emotional arousal. Biofeedback Induced Anxiety resulted in a greater reduction of trait anxiety as measured by the Multiple Affect Adjective Check List than did the no-treatment group or the conventonal Induced Anxiety group. The conventional Induced Anxiety group did not differ significantly from the no-treatment control group.

  9. Management of Facial Synkinesis with a Combination of BTX-A and Biofeedback: A Randomized Trial.

    Science.gov (United States)

    Pourmomeny, Abbas Ali; Asadi, Sahar; Cheatsaz, Ahmad

    2015-11-01

    Synkinesis and facial asymmetry due to facial nerve palsy are distressing conditions that affect quality of life. Unfortunately, these sequelae of facial nerve palsy are unresolved. The aim of this study was to investigate the efficacy of a combination of biofeedback therapy and botulinum toxin A (BTX-A) injection for the management of synkinesis and asymmetry of facial muscles. Among referrals from three university hospitals, 34 patients with facial synkinesis were divided randomly into two groups. All participants were evaluated using Photoshop software, videotape, and facial grading system (FGS). The first group received a single dose of BTX-A at the start of treatment, while the second group received normal saline as a control. Both groups received electromyography (EMG) biofeedback three times a week for 4 months. The mean FGS values for the BTX group before and after treatment were 55.17 and 74.17, respectively, and those for the biofeedback group were 66.31 and 81.37, respectively. Moreover, it was shown that in both groups oral-ocular and oculo-oral synkinesis decreased significantly after treatment compared with before treatment (PPhotoshop and videotape, these differences were even greater. Despite the decrease in synkinesis in both groups after treatment, there were no significant differences between the two treatment groups (P>0.05). Biofeedback therapy is as effective as the combination of biofeedback and BTX in reducing synkinesis and recovery of facial symmetry in Bell's palsy.

  10. The effect of biofeedback therapy on dyssynergic constipation in patients with or without Irritable Bowel Syndrome

    Directory of Open Access Journals (Sweden)

    Tannaz Ahadi

    2014-01-01

    Full Text Available Background: The Rome II and III diagnostic criteria for dyssynergic defecation recommended the exclusion of irritable bowel syndrome (IBS. This study determined the effect of biofeedback therapy on dyssynergic constipation in patients with or without IBS. Materials and Methods: This study was a nonrandomized, single blinded, semi experimental study. Dyssynergic defecation patients with and without IBS were asked to undergo biofeedback therapy 8 sessions. The defecation dynamics and balloon expulsion time were evaluated before, at the end and 1 month after the biofeedback therapy. IBS symptoms were graded using a 4-point Likert scale. Mann-Whitney U-test, Wilcoxon test and Friedman test were applied to analyze data using SPSS software package (SPSS Inc., Chicago, IL, USA. Results: After the biofeedback therapy, the IBS symptoms have been decreased significantly (the median of 2 before and 1 after therapy, P 0.05 with respect to outcome. No complication was observed in treatment groups. Conclusion: Dyssynergic constipation patients with and without IBS will likely benefit from biofeedback therapy.

  11. Efficacy of a telerehabilitation intervention programme using biofeedback among computer operators.

    Science.gov (United States)

    Golebowicz, Merav; Levanon, Yafa; Palti, Ram; Ratzon, Navah Z

    2015-01-01

    Computer operators spend long periods of time sitting in a static posture at computer workstations and therefore have an increased exposure to work-related musculoskeletal disorders (WRMSD). The present study is aimed at investigating the feasibility and effectiveness of a tele-biofeedback ergonomic intervention programme among computer operators suffering from WRMSD. Twelve subjects with WRMSD were assigned an ergonomic intervention accompanied by remote tele-biofeedback training, which was practised at their workstations. Evaluations of pain symptoms and locations, body posture and psychosocial characteristics were carried out before and after the intervention in the workplace. The hypothesis was partially verified as it showed improved body position at the workstation and decreased pain in some body parts. Tele-biofeedback, as part of an intervention, appears to be feasible and efficient for computer operators who suffer from WRMSD. This study encourages further research on tele-health within the scope of occupational therapy practice. Practitioner summary: Research concerning tele-health using biofeedback is scarce. The present study analyses the feasibility and partial effectiveness of a tele-biofeedback ergonomic intervention programme for computer operators suffering from WRMSD. The uniqueness and singularity of this study is the usage of remote communication between participants and practitioners through the Internet.

  12. Effects of electromyographic and mechanomyographic biofeedback on upper trapezius muscle activity during standardized computer work

    DEFF Research Database (Denmark)

    Madeleine, Pascal; Vedsted, Pernille; Blangsted, Anne Katrine

    2006-01-01

    The purpose of this laboratory study was to investigate the effects of surface electromyography (EMG)- and mechanomyography (MMG)-based audio and visual biofeedback during computer work. Standardized computer work was performed for 3 min with/without time constraint and biofeedback in a randomize...... alternative to EMG in ergonomics. A lowering of the trapezius muscle activity may contribute to diminish the risk of work related musculoskeletal disorders development.......The purpose of this laboratory study was to investigate the effects of surface electromyography (EMG)- and mechanomyography (MMG)-based audio and visual biofeedback during computer work. Standardized computer work was performed for 3 min with/without time constraint and biofeedback in a randomized......) values as well as the work performance in terms of number of completed graph/mouse clicks/errors, the rating of perceived exertion (RPE) and the usefulness of the biofeedback were assessed. The duration of muscle activity above the threshold was significantly lower with MMG compared with EMG as source...

  13. Stress and Anxiety Management in Nursing Students: Biofeedback and Mindfulness Meditation.

    Science.gov (United States)

    Ratanasiripong, Paul; Park, Janet F; Ratanasiripong, Nop; Kathalae, Duangrat

    2015-09-01

    The current study investigated the efficacy of two brief intervention programs-biofeedback and mindfulness meditation-on levels of state anxiety and perceived stress in second-year Thai nursing students as they began clinical training. Eighty-nine participants from a public nursing college in Thailand were randomly assigned to one of three groups: biofeedback group, mindfulness meditation group, or a control group. All participants were given pre- and postintervention surveys, which included demographic information; the State-Trait Anxiety Inventory (State Anxiety Scale); and the Perceived Stress Scale. Findings indicated that biofeedback significantly reduced anxiety and maintained stress levels in nursing students. Mindfulness meditation similarly decreased anxiety levels, while also significantly lowering stress levels. The biofeedback group exhibited significant reduction in anxiety levels among the three groups at postintervention. Despite stressors and demands nursing students experience as they begin clinical practice, study findings support the use of biofeedback and mindfulness meditation interventions to assist nursing students in managing stress and anxiety. Copyright 2015, SLACK Incorporated.

  14. EMG biofeedback training in adult attention-deficit/hyperactivity disorder: An active (control) training?

    Science.gov (United States)

    Barth, Beatrix; Mayer, Kerstin; Strehl, Ute; Fallgatter, Andreas J; Ehlis, Ann-Christine

    2017-06-30

    The present study aimed at revealing neurophysiological effects induced by electromyography (EMG) based biofeedback, considered as a semi-active control condition in neurofeedback studies, in adult attention-deficit/hyperactivity disorder (ADHD) patients. 20 adult ADHD patients trained their muscle activity in the left and right supraspinatus muscle over the course of 30 EMG biofeedback sessions. Changes induced by the EMG feedback were evaluated at a clinical and neurophysiological level; additionally, the relation between changes in EEG activity recorded at the vertex over the training course and changes of symptom severity over the treatment course were assessed in order to investigate the mechanisms underlying clinical effects of EMG biofeedback. Participants showed significant behavioral improvements on a self-rating scale. There was a significant increase in alpha power, but no significant changes in the delta frequency range; changes in the theta and beta frequency range were not significant after adjustment for multiple comparisons. No statistically significant correlation was found between changes in EEG frequency bands and changes in ADHD symptoms. The current results assessed by means of a single-electrode EEG constitute a starting point regarding a clearer understanding of mechanisms underlying clinical effects of EMG biofeedback. Although we did not reveal systematic effects induced by EMG feedback on brain activity it remains an open question whether EMG biofeedback induces changes in brain regions or parameters we did not gather in the present study (e.g. motor cortex). Copyright © 2017 Elsevier B.V. All rights reserved.

  15. The effect of heart rate variability biofeedback training on stress and anxiety: a meta-analysis.

    Science.gov (United States)

    Goessl, V C; Curtiss, J E; Hofmann, S G

    2017-11-01

    Some evidence suggests that heart rate variability (HRV) biofeedback might be an effective way to treat anxiety and stress symptoms. To examine the effect of HRV biofeedback on symptoms of anxiety and stress, we conducted a meta-analysis of studies extracted from PubMed, PsycINFO and the Cochrane Library. The search identified 24 studies totaling 484 participants who received HRV biofeedback training for stress and anxiety. We conducted a random-effects meta-analysis. The pre-post within-group effect size (Hedges' g) was 0.81. The between-groups analysis comparing biofeedback to a control condition yielded Hedges' g = 0.83. Moderator analyses revealed that treatment efficacy was not moderated by study year, risk of study bias, percentage of females, number of sessions, or presence of an anxiety disorder. HRV biofeedback training is associated with a large reduction in self-reported stress and anxiety. Although more well-controlled studies are needed, this intervention offers a promising approach for treating stress and anxiety with wearable devices.

  16. Real-time biofeedback to target risk of anterior cruciate ligament injury: a technical report for injury prevention and rehabilitation.

    Science.gov (United States)

    Ford, Kevin R; DiCesare, Christopher A; Myer, Gregory D; Hewett, Timothy E

    2015-05-20

    Biofeedback training enables an athlete to alter biomechanical and physiological function by receiving biomechanical and physiological data concurrent with or immediately after a task. To compare the effects of 2 different modes of real-time biofeedback focused on reducing risk factors related to anterior cruciate ligament injury. Randomized crossover study design. Biomechanics laboratory and sports medicine center. Female high school soccer players (age 14.8 ± 1.0 y, height 162.6 ± 6.8 cm, mass 55.9 ± 7.0 kg; n = 4). A battery of kinetic- or kinematic-based real-time biofeedback during repetitive double-leg squats. Baseline and posttraining drop vertical jumps were collected to determine if either feedback method improved high injury risk landing mechanics. Maximum knee abduction moment and angle during the landing was significantly decreased after kinetic-focused biofeedback (P = .04). The reduced knee abduction moment during the drop vertical jumps after kinematic-focused biofeedback was not different (P = .2). Maximum knee abduction angle was significantly decreased after kinetic biofeedback (P < .01) but only showed a trend toward reduction after kinematic biofeedback (P = .08). The innovative biofeedback employed in the current study reduced knee abduction load and posture from baseline to posttraining during a drop vertical jump.

  17. ABILITY TO SELF-CONTROL IN BIOFEEDBACK GAMES AND SUCCESS OF PUPILS OF 11–13 YEARS

    Directory of Open Access Journals (Sweden)

    O. B. Gileva

    2013-01-01

    Full Text Available The relation of indicators of biofeedback and the school success was studied. The relation of pulse interval, wave structure of heart rate, Sacred George's index (StGe and progress of children is found out. Results are discussed with relations of use of computer biofeedback games for studying of psychophysiological features and predictors of school success.

  18. Behavioural and physiological outcomes of biofeedback therapy on dental anxiety of children undergoing restorations: a randomised controlled trial.

    Science.gov (United States)

    Dedeepya, P; Nuvvula, S; Kamatham, R; Nirmala, S V S G

    2014-04-01

    To explore the efficacy of biofeedback as possible alternative means of psychological behaviour guidance in children receiving dental restorations. Randomised clinical trial with a cross over design carried out on 40 children (19 boys and 21 girls) to determine the efficacy of biofeedback in reducing the dental anxiety through subjective and objective measures during restorative treatments under cotton roll isolation without administration of local analgesia. Highly anxious children with a minimum of five carious lesions were trained to lower their anxiety using biofeedback in five sessions within a 4-week interval, each session lasting for 45 min. After initial training, children were randomly divided into two groups and restorations were placed in four sequential therapeutic sessions with a 1-week interval and a follow-up visit 3 months later. First group received biofeedback in the second and third sessions; whereas the second group received biofeedback in the first and third sessions. Biofeedback therapy in children led to lower levels of anxiety in the initial appointments when assessed objectively, however the subjective methods of evaluation could not depict any statistically significant difference. Biofeedback can be used in the initial visits for dentally anxious children and the usage of simpler biofeedback machines for these appointments in dental setup is suggested.

  19. Botulinum toxin type-A injection to treat patients with intractable anismus unresponsive to simple biofeedback training.

    Science.gov (United States)

    Zhang, Yong; Wang, Zhen-Ning; He, Lei; Gao, Ge; Zhai, Qing; Yin, Zhi-Tao; Zeng, Xian-Dong

    2014-09-21

    To evaluate the efficacy of botulinum toxin type A injection to the puborectalis and external sphincter muscle in the treatment of patients with anismus unresponsive to simple biofeedback training. This retrospective study included 31 patients suffering from anismus who were unresponsive to simple biofeedback training. Diagnosis was made by anorectal manometry, balloon expulsion test, surface electromyography of the pelvic floor muscle, and defecography. Patients were given botulinum toxin type A (BTX-A) injection and pelvic floor biofeedback training. Follow-up was conducted before the paper was written. Improvement was evaluated using the chronic constipation scoring system. BTX-A injection combined with pelvic floor biofeedback training achieved success in 24 patients, with 23 maintaining persistent satisfaction during a mean period of 8.4 mo. BTX-A injection combined with pelvic floor biofeedback training seems to be successful for intractable anismus.

  20. Portable EMG devices, Biofeedback and Contingent Electrical Stimulation applications in Bruxism

    DEFF Research Database (Denmark)

    Castrillon, Eduardo

    Portable EMG devices, Biofeedback and Contingent Electrical Stimulation applications in Bruxism Eduardo Enrique, Castrillon Watanabe, DDS, MSc, PhD Section of Orofacial Pain and Jaw Function, Department of Dentistry, Aarhus University, Aarhus, Denmark; Scandinavian Center for Orofacial Neuroscience...... Summary: Bruxism is a parafunctional activity, which involves the masticatory muscles and probably it is as old as human mankind. Different methods such as portable EMG devices have been proposed to diagnose and understand the pathophysiology of bruxism. Biofeedback / contingent electrical stimulation...... characteristics make it complicated to assess bruxism using portable EMG devices. The possibility to assess bruxism like EMG activity on a portable device made it possible to use biofeedback and CES approaches in order to treat / manage bruxism. The available scientific information about CES effects on bruxism...

  1. Biofeedback Intervention for Stress, Anxiety, and Depression among Graduate Students in Public Health Nursing.

    Science.gov (United States)

    Ratanasiripong, Paul; Kaewboonchoo, Orawan; Ratanasiripong, Nop; Hanklang, Suda; Chumchai, Pornlert

    2015-01-01

    Globally, graduate students have been found to have high prevalence of mental health problems. With increasing severity of mental health problems on university campuses and limited resources for mental health treatment, alternative interventions are needed. This study investigated the use of biofeedback training to help reduce symptoms of stress, anxiety, and depression. A sample of 60 graduate students in public health nursing was randomly assigned to either the biofeedback intervention or the control group. Results indicated that biofeedback intervention was effective in significantly reducing the levels of stress, anxiety, and depression over the 4-week period, while the control group had increases in symptoms of anxiety and depression over the same timeframe. As future leaders in the public health nursing arena, the more psychologically healthy the graduate students in public health nursing are, the better the public health nursing professionals they will be as they go forth to serve the community after graduation.

  2. Biofeedback Intervention for Stress, Anxiety, and Depression among Graduate Students in Public Health Nursing

    Directory of Open Access Journals (Sweden)

    Paul Ratanasiripong

    2015-01-01

    Full Text Available Globally, graduate students have been found to have high prevalence of mental health problems. With increasing severity of mental health problems on university campuses and limited resources for mental health treatment, alternative interventions are needed. This study investigated the use of biofeedback training to help reduce symptoms of stress, anxiety, and depression. A sample of 60 graduate students in public health nursing was randomly assigned to either the biofeedback intervention or the control group. Results indicated that biofeedback intervention was effective in significantly reducing the levels of stress, anxiety, and depression over the 4-week period, while the control group had increases in symptoms of anxiety and depression over the same timeframe. As future leaders in the public health nursing arena, the more psychologically healthy the graduate students in public health nursing are, the better the public health nursing professionals they will be as they go forth to serve the community after graduation.

  3. Combined use of autogenic therapy and biofeedback in training effective control of heart rate by humans

    Science.gov (United States)

    Cowings, P. S.

    1977-01-01

    Experiments were performed on 24 men and women (aged 20-27 yr) in three equal groups who were taught to control their own heart rates by autogenic training and biofeedback under dark and sound-isolated conditions. Group I was parasympathetic dominant, group II was sympathetic dominant, and group III consisted of parasympathetic-dominant subjects and controls who received only biofeedback of their own heart rates. The results corroborate three hypotheses: (1) subjects with para-sympathetic-dominant autonomic profiles perform in a way that is both qualitatively and quantitatively different from subjects with sympathetic-dominant autonomic profiles; (2) tests of interindividual variability yield data relevant to individual performance in visceral learning tasks; and (3) the combined use of autogenic training, biofeedback, and verbal feedback is suitable for conditioning large stable autonomic responses in humans.

  4. Enhancing generalisation in biofeedback intervention using the challenge point framework: A case study

    Science.gov (United States)

    HITCHCOCK, ELAINE R.; BYUN, TARA McALLISTER

    2014-01-01

    Biofeedback intervention can help children achieve correct production of a treatment-resistant error sound, but generalisation is often limited. This case study suggests that generalisation can be enhanced when biofeedback intervention is structured in accordance with a “challenge point” framework for speech-motor learning. The participant was an 11-year-old with residual /r/ misarticulation who had previously attained correct /r/ production through a structured course of ultrasound biofeedback treatment but did not generalise these gains beyond the word level. Treatment difficulty was adjusted in an adaptive manner following predetermined criteria for advancing, maintaining, or moving back a level in a multidimensional hierarchy of functional task complexity. The participant achieved and maintained virtually 100% accuracy in producing /r/ at both word and sentence levels. These preliminary results support the efficacy of a semi-structured implementation of the challenge point framework as a means of achieving generalisation and maintenance of treatment gains. PMID:25216375

  5. Patient-Controlled Biofeedback Device for the Treatment of Fecal Incontinence: A Pilot Study.

    Science.gov (United States)

    Damin, Daniel C; Hommerding, Felipe; Schirmer, Delber; Sanches, Paulo R S; Silva Junior, Danton P; Müller, André F; Thome, Paulo R O

    2017-06-01

    Although biofeedback has been used as a first-line therapy for fecal incontinence, it is known to be time consuming and demands attendance to a hospital during the whole period of treatment. In this study, we describe a new biofeedback device specifically developed for home treatment of fecal incontinence, which consists of a microprocessor controlled unit able to register and store the anal pressure waves corresponding to exercises performed by patients at home. In order to test the new device, a pilot study including ten patients with fecal incontinence was conducted. Evaluation of patients before and after the biofeedback training showed significant improvement in manometric and clinical parameters of anal continence. The new method may improve compliance of patients with the training program and reduce their need to be supervised during the treatment. It might represent a new alternative for the treatment of fecal incontinence.

  6. ANALYSIS OF A DIFFERENTIATED APPROACH TO THE APPOINTMENT OF DICK METHODS IN BIOFEEDBACK CORRECTION AUTONOMIC DYSFUNCTION

    Directory of Open Access Journals (Sweden)

    A. G. Polyakova

    2013-01-01

    Full Text Available Goal of research: analysis of the effectiveness of Biofeedback therapy is differentiated depending on the clinical forms of autonomic dysfunction. Exchange rate control efficacy of biofeedback hardware was conducted on the dynamics of clinical andl aboratory data, surveys and assessment of the functional State of the SNC using heart rate variability, vegetative resonance test, Kerdo index definition, as well as èlektrokardiografiče applications and questionnaires, characterizing the State of psychoemotional sphere (Spilbergera–Hanina, test, Luscher. Laboratory tests include a complete blood count with evaluation of Adaptive reactions of the organism. The results of the rehabilitation complex of the patients with the use of biofeedback have confirmed its effectiveness.

  7. Visual Biofeedback using trans-perineal ultrasound during the second stage of labor.

    Science.gov (United States)

    Gilboa, Yinon; Frenkel, Tahl I; Schlesinger, Yael; Rousseau, Sofie; Hamiel, Daniel; Achiron, Reuven; Perlman, Sharon

    2017-11-20

    to assess the obstetrical and psychological effect of visual biofeedback using trans-perineal ultrasound (TPU) during the second stage of labor. Visual biofeedback using TPU was performed prospectively during the second stage of labor in twenty-six low risk nulliparous women. Pushing efficacy was assessed by the angle of progression at rest and during pushing efforts before and after observing the ultrasound screen. Obstetrical outcomes included level of perineal tearing, mode of delivery and length of the second stage. Psychological outcomes were assessed via self-report measures during the postnatal hospital stay. These included measures of perceived control and maternal satisfaction with childbirth as well as level of maternal feelings of connectedness toward her newborn. Obstetrical and psychological results were compared to a control group (n=69) who received standard obstetrical coaching by midwifes. Pushing efficacy significantly increased following visual biofeedback by TPU (p = 0.01). A significant association was found between the visual biofeedback and an intact perineum following delivery (p = 0.03). No significant differences were found in regard to mode of delivery or the length of the second stage. Feelings of maternal connectedness towards the newborn were significantly higher in the visual biofeedback group relative to non-biofeedback controls (p = 0.003). The results of this pilot study implicate that TPU may serve as a complementary tool to coached maternal pushing during the second stage of labor with obstetrical as well as psychological benefits. Further studies are required to confirm our findings and define the exact timing for optimal results. This article is protected by copyright. All rights reserved.

  8. The effect of biofeedback therapy on dyssynergic constipation in patients with or without Irritable Bowel Syndrome.

    Science.gov (United States)

    Ahadi, Tannaz; Madjlesi, Faezeh; Mahjoubi, Bahar; Mirzaei, Rezvan; Forogh, Bijan; Daliri, Seyedeh Somayeh; Derakhshandeh, Seyed Majid; Behbahani, Roxana Bazaz; Raissi, G Reza

    2014-10-01

    The Rome II and III diagnostic criteria for dyssynergic defecation recommended the exclusion of irritable bowel syndrome (IBS). This study determined the effect of biofeedback therapy on dyssynergic constipation in patients with or without IBS. This study was a nonrandomized, single blinded, semi experimental study. Dyssynergic defecation patients with and without IBS were asked to undergo biofeedback therapy 8 sessions. The defecation dynamics and balloon expulsion time were evaluated before, at the end and 1 month after the biofeedback therapy. IBS symptoms were graded using a 4-point Likert scale. Mann-Whitney U-test, Wilcoxon test and Friedman test were applied to analyze data using SPSS software package (SPSS Inc., Chicago, IL, USA). After the biofeedback therapy, the IBS symptoms have been decreased significantly (the median of 2 before and 1 after therapy, P anismus index in IBS group by the mean of 0.75 ± 0.31, 0.28 ± 0.07 and 0.28 ± 0.06 in three phases, respectively. Similar results were found in non-IBS patients (the mean of 0.74 ± 0.32, 0.28 ± 0.08, 0.27 ± 0.08 in three phases, respectively). The symptoms of constipation (sensation of incomplete evacuation, difficult and painful defecation), defecation facilitative manual maneuver frequency, pelvic floor muscles resting amplitude and strain amplitude decreased and squeezing amplitude improved significantly after biofeedback therapy in both groups with and without IBS (P 0.05) with respect to outcome. No complication was observed in treatment groups. Dyssynergic constipation patients with and without IBS will likely benefit from biofeedback therapy.

  9. Audiovisual biofeedback improves image quality and reduces scan time for respiratory-gated 3D MRI

    International Nuclear Information System (INIS)

    Lee, D; Keall, P; Kim, T; Greer, P B; Arm, J

    2014-01-01

    The purpose of this study was to test the hypothesis that audiovisual (AV) biofeedback can improve image quality and reduce scan time for respiratory-gated 3D thoracic MRI. For five healthy human subjects respiratory motion guidance in MR scans was provided using an AV biofeedback system, utilizing real-time respiratory motion signals. To investigate the improvement of respiratory-gated 3D MR images between free breathing (FB) and AV biofeedback (AV), each subject underwent two imaging sessions. Respiratory-related motion artifacts and imaging time were qualitatively evaluated in addition to the reproducibility of external (abdominal) motion. In the results, 3D MR images in AV biofeedback showed more anatomic information such as a clear distinction of diaphragm, lung lobes and sharper organ boundaries. The scan time was reduced from 401±215 s in FB to 334±94 s in AV (p-value 0.36). The root mean square variation of the displacement and period of the abdominal motion was reduced from 0.4±0.22 cm and 2.8±2.5 s in FB to 0.1±0.15 cm and 0.9±1.3 s in AV (p-value of displacement <0.01 and p-value of period 0.12). This study demonstrated that audiovisual biofeedback improves image quality and reduces scan time for respiratory-gated 3D MRI. These results suggest that AV biofeedback has the potential to be a useful motion management tool in medical imaging and radiation therapy procedures.

  10. Real-Time Assessment of the Effect of Biofeedback Therapy with Migraine: A Pilot Study.

    Science.gov (United States)

    Odawara, Miyuki; Hashizume, Masahiro; Yoshiuchi, Kazuhiro; Tsuboi, Koji

    2015-12-01

    Biofeedback therapy has been reported to be effective in the treatment of migraine. However, previous studies have assessed its effectiveness using paper-and-pencil diaries, which are not very reliable. The objective of the present pilot study was to investigate the feasibility of using computerized ecological momentary assessment (EMA) for evaluating the efficacy of BF treatment for migraine in a randomized controlled trial. The subjects comprised one male and 26 female patients with migraine. They were randomly assigned to either biofeedback or wait-list control groups. Patients were asked to carry a palmtop-type computer to record momentary symptoms for 4 weeks before and after biofeedback treatment. The primary outcome measure was headache intensity. The secondary outcome measures included psychological stress, anxiety, irritation, headache-related disability and the frequency (number of days per month) of migraine attack and of headache of at least moderate intensity (pain rating ≥50). Headache intensity showed significant main effects of period (before vs. after therapy, p = 0.02) and group (biofeedback vs. control groups, p = 0.42) and a significant period × group interaction (p Biofeedback reduced the duration of headaches by 1.9 days, and the frequency of days when headache intensity was ≥50 by 2.4 times. In addition, headache-related disability, psychological stress, depression, anxiety, and irritation were significantly improved. The present study used computerized EMA to show that biofeedback could improve the symptoms of migraine, including psychological stress and headache-related disability.

  11. BIOFEEDBACK: A NEW METHOD FOR CORRECTION OF MOTOR DISORDERS IN PATIENTS WITH MULTIPLE SCLEROSIS

    Directory of Open Access Journals (Sweden)

    Ya. S. Pekker

    2014-01-01

    Full Text Available Major disabling factors in multiple sclerosis is motor disorders. Rehabilitation of such violations is one of the most important medical and social problems. Currently, most of the role given to the development of methods for correction of motor disorders based on accessing natural resources of the human body. One of these methods is the adaptive control with biofeedback (BFB. The aim of our study was the correction of motor disorders in multiple sclerosis patients using biofeedback training. In the study, we have developed scenarios for training rehabilitation program computer EMG biofeedback aimed at correction of motor disorders in patients with multiple sclerosis (MS. The method was tested in the neurological clinic of SSMU. The study included 9 patients with definite diagnosis of MS with the presence of the clinical picture of combined pyramidal and cerebellar symptoms. Assessed the effectiveness of rehabilitation procedures biofeedback training using specialized scales (rating scale functional systems Kurtzke; questionnaire research quality of life – SF-36, evaluation of disease impact Profile – SIP and score on a scale fatigue – FSS. In the studied group of patients decreased score on a scale of fatigue (FSS, increased motor control (SIP2, the physical and mental components of health (SF-36. The tendency to reduce the amount of neurological deficit by reducing the points on the pyramidal Kurtske violations. Analysis of the exchange rate dynamics of biofeedback training on EMG for trained muscles indicates an increase in the recorded signal OEMG from session to session. Proved a tendency to increase strength and coordination trained muscles of patients studied.Positive results of biofeedback therapy in patients with MS can be recommended to use this method in the complex rehabilitation measures to correct motor and psycho-emotional disorders.

  12. Supplementary home biofeedback improves quality of life in younger patients with fecal incontinence.

    Science.gov (United States)

    Bartlett, Lynne; Sloots, Kathryn; Nowak, Madeleine; Ho, Yik-Hong

    2015-01-01

    Biofeedback is a scarce, resource-intensive clinical therapy. It is used to treat patients with bowel problems, including fecal incontinence (FI), who fail to respond to simple dietary advice, medication, or pelvic floor exercises. Populations are aging and younger cohorts use technology in managing their health, affording FI self-management opportunities. Does supplementary home-based biofeedback improve FI and quality of life (QOL)? Seventy-five incontinent participants (12 male), mean age 61.1 years, consented to participate. Thirty-nine patients (5 male) were randomized to the standard biofeedback protocol plus daily home use of a Peritron perineometer (intervention) and 36 patients (7 male) to the standard biofeedback protocol (control). On completion of the study each perineometer exercise session was rated for technique by 2 raters, blinded to the patient and order of sessions. With the exception of Fecal Incontinence Quality of Life Scale lifestyle improvement (intervention--9.1% vs. controls--0.3%, P=0.026) and embarrassment improvement (intervention--50.0% vs. controls--18.3%, P=0.026), supplementary home biofeedback did not result in greater clinical improvement for the intervention group as a whole. However, on stratification around the mean age, continence and QOL of younger people in the intervention group were significantly better than those of their control counterparts. Graphed perineometer sessions demonstrated high compliance and improvement in exercise technique. Perineometers provided reassurance, motivation, and an exercise reminder ensuring that confidence was achieved quickly. Home biofeedback was acceptable and well tolerated by all users. Younger participants significantly benefited from using this technology.

  13. Negative transfer of heart rate control following biofeedback training: a partial replication.

    Science.gov (United States)

    Steptoe, A; Macready, D

    1985-09-01

    Ability to raise and lower heart rate (HR) on instruction was tested before and after unidirectional biofeedback training in two groups of 10 male volunteers. Instructional control was assessed in 2-min trials before training, and after 5 and 10 biofeedback trials of increasing (Group I) and decreasing (Group D) HR. The magnitude of HR elevations produced by Group D diminished following training, while modifications in Group I were unchanged. This negative transfer effect is discussed in relation to whether voluntary speeding and slowing HR reflect distinct capacities.

  14. Changes in muscle thickness after exercise and biofeedback in people with low back pain.

    Science.gov (United States)

    Partner, Shandi L; Sutherlin, Mark Alan; Acocello, Shellie; Saliba, Susan A; Magrum, Eric M; Hart, Joe M

    2014-11-01

    Individuals with low back pain (LBP) have reduced function of the transversus abdominis (TrA) and lumbar multifidus (LM) muscles. Biofeedback during exercise may increase the ability to contract the TrA and LM muscles compared with exercise alone. To compare TrA preferential activation ratio (PAR) and the percent change in LM-muscle thickness in patients with LBP history before and after exercise with or without biofeedback. Controlled laboratory study. University research laboratory. 20 LBP individuals, 10 exercise alone and 10 exercise with biofeedback. Patients were allotted to tabletop exercises in isolation or tabletop exercises with visual, auditory, and tactile biofeedback. TrA PAR and percent change in LM-muscle thickness. There were no differences between groups at baseline (all P > .05). Nonparametric statistics showed decreased resting muscle thickness for total lateral abdominal-wall muscles (P = .007) but not TrA (P = .410) or LM (P = .173). Percent TrA thickness increased from table to standing positions before (P = .006) and after exercise (P = .009). TrA PAR increased after exercise (pre 0.01 ± 0.02, post 0.03 ± 0.04, P = .033) for all patients and for exercise with biofeedback (pre 0.02 ± 0.01, post 0.03 ± 0.01, P = .037) but not for exercise alone (pre 0.01 ± 0.02, post 0.02 ± 0.05, P = .241). No group differences were observed for TrA PAR before (exercise 0.01 ± 0.02, exercise with biofeedback 0.02 ± 0.01, P = .290) or after exercise (exercise 0.02 ± 0.05, exercise with biofeedback 0.03 ± 0.01, P = .174). There were no group differences in LM percent change before exercise (P = .999) or after exercise (P = .597). In addition, no changes were observed in LM percent change as a result of exercise among all participants (P = .391) or for each group (exercise P = .508, exercise with biofeedback P = .575). TrA PAR increased after a single session of exercises, whereas no thickness changes occurred in LM.

  15. Relaxation in the XX quantum chain

    International Nuclear Information System (INIS)

    Platini, Thierry; Karevski, Dragi

    2007-01-01

    We present the results obtained on the magnetization relaxation properties of an XX quantum chain in a transverse magnetic field. We first consider an initial thermal kink-like state where half of the chain is initially thermalized at a very high temperature T b while the remaining half, called the system, is put at a lower temperature T s . From this initial state, we derive analytically the Green function associated with the dynamical behaviour of the transverse magnetization. Depending on the strength of the magnetic field and on the temperature of the system, different regimes are obtained for the magnetic relaxation. In particular, with an initial droplet-like state, that is a cold subsystem of the finite size in contact at both ends with an infinite temperature environment, we derive analytically the behaviour of the time-dependent system magnetization

  16. Relaxed Binaural LCMV Beamforming

    NARCIS (Netherlands)

    Koutrouvelis, A.; Hendriks, R.C.; Heusdens, R.; Jensen, Jesper Rindom

    2017-01-01

    In this paper, we propose a new binaural beamforming technique, which can be seen as a relaxation of the linearly constrained minimum variance (LCMV) framework. The proposed method can achieve simultaneous noise reduction and exact binaural cue preservation of the target source, similar to the

  17. Breathing biofeedback as an adjunct to exposure in cognitive behavioral therapy hastens the reduction of PTSD symptoms: a pilot study.

    Science.gov (United States)

    Rosaura Polak, A; Witteveen, Anke B; Denys, Damiaan; Olff, Miranda

    2015-03-01

    Although trauma-focused cognitive behavioral therapy (TF-CBT) with exposure is an effective treatment for posttraumatic stress disorder (PTSD), not all patients recover. Addition of breathing biofeedback to exposure in TF-CBT is suggested as a promising complementary technique to improve recovery of PTSD symptoms. Patients (n = 8) with chronic PTSD were randomized to regular TF-CBT or TF-CBT with complementary breathing biofeedback to exposure. PTSD symptoms were measured before, during and after TF-CBT with the Impact of Event Scale-Revised. The results show that breathing biofeedback is feasible and can easily be complemented to TF-CBT. Although PTSD symptoms significantly decreased from pre to post treatment in both conditions, there was a clear trend towards a significantly faster (p = .051) symptom reduction in biofeedback compared to regular TF-CBT. The most important limitation was the small sample size. The hastened clinical improvement in the biofeedback condition supports the idea that breathing biofeedback may be an effective complementary component to exposure in PTSD patients. The mechanism of action of breathing biofeedback may relate to competing working memory resources decreasing vividness and emotionality, similar to eye movement desensitization and reprocessing. Future research is needed to examine this.

  18. IMPLEMENTATION OF BIOFEEDBACK IN A CLOSED LOOP OF HEART RATE VARIABILITY AND PACED BREATHING IN PATIENTS WITH ARTERIAL HYPERTENSION

    Directory of Open Access Journals (Sweden)

    O. L. Kulik

    2014-06-01

    Full Text Available The effectiveness of biofeedback in a closed loop of heart rate variability (HRV and paced breathing in patients with arterial hypertension was studied. 61 subjects with arterial hypertension (31 females and 30 males, mean age 56.8 ± 6.2 years were examined. In accordance with the objective of the study all subjects were divided into 2 groups: 1 – biofeedback group (34 subjects and 2 – the comparison group (27 subjects. 5 biofeedback sessions were performed in biofeedback group. In the comparison group only two biofeedback sessions were performed – at admission and before discharge from the hospital. Efficacy of biofeedback was evaluated by comparing the values of systolic and diastolic blood pressure (SBP and DBP, respectively, heart rate (HR, HRV indices, indicators of optimality (O, sensitivity (S and efficiency (E and BQI index at admission and discharge in both groups of patients. The use of biofeedback in arterial hypertension subjects allowed to achieve better control of heart rate, systolic and diastolic blood pressure and improves HRV indices. The positive dynamics of optimality and the integral BQI values indicated a training effect of regulation systems.

  19. Comparing electromagnetic stimulation with electrostimulation plus biofeedback in treating male refractory chronic pelvic pain syndrome

    Directory of Open Access Journals (Sweden)

    Min-Hsin Yang

    2017-09-01

    Conclusion: Both EMS and ESB physical therapy of the pelvic floor muscle effectively reduce pain, increase the QoL, and improve urinary tract symptoms in male CPPS patients who are refractory to medical treatments. The combination therapy of ES plus biofeedback demonstrates additional benefits in pain and QoL when compared with EMS alone.

  20. Flex Sensor Based Biofeedback Monitoring for Post-Stroke Fingers Myopathy Patients

    Science.gov (United States)

    Garda, Y. R.; Caesarendra, W.; Tjahjowidodo, T.; Turnip, A.; Wahyudati, S.; Nurhasanah, L.; Sutopo, D.

    2018-04-01

    Hands are one of the crucial parts of the human body in carrying out daily activities. Accidents on the hands decreasing in motor skills of the hand so that therapy is necessary to restore motor function of the hand. In addition to accidents, hand disabilities can be caused by certain diseases, e.g. stroke. Stroke is a partial destruction of the brain. It occurs if the arteries that drain blood to the brain are blocked, or if torn or leak. The purpose of this study to make biofeedback monitoring equipment for post-stroke hands myopathy patients. Biofeedback is an alternative method of treatment that involves measuring body functions measured subjects such as skin temperature, sweat activity, blood pressure, heart rate and hand paralysis due to stroke. In this study, the sensor used for biofeedback monitoring tool is flex sensor. Flex sensor is a passive resistive device that changes its resistance as the sensor is bent. Flex sensor converts the magnitude of the bend into electrical resistance, the greater the bend the greater the resistance value. The monitoring used in this biofeedback monitoring tool uses Graphical User Interface (GUI) in C# programming language. The motivation of the study is to monitor and record the progressive improvement of the hand therapy. Patients who experienced post-stroke can see the therapy progress quantitatively.

  1. Biofeedback and physiotherapy versus physiotherapy alone in the treatment of genuine stress urinary incontinence

    DEFF Research Database (Denmark)

    Glavind, K; Nøhr, S B; Walter, S

    1996-01-01

    . The effect of the treatment was determined by a standardized pad-weighing test. Long-term status was determined using a questionnaire after 2-3 years. Thirty-four women completed the treatment. The study showed a statistically significant better improvement in the biofeedback group. The long-term effect...

  2. Biofeedback for Developing Self-Control of Tension and Stress in One's Hierarchy of Psychological States.

    Science.gov (United States)

    Cassel, Russell

    1985-01-01

    Describes six stage hierarchial patterns in the development of self-control through biofeedback. The stages include Skeletal and Striated Muscle Tension; Visceral Involvement-Anxiety Neuroses; Chronic Physiological Dysfunctioning; Decision Making Competency; Twilight Learning-Permissive Concentration; and Autogenic Feedback Training. (BL)

  3. A randomized clinical trial comparing fitness and biofeedback training versus basic treatment in patients with fibromyalgia

    NARCIS (Netherlands)

    van Santen, Marijke; Bolwijn, Paulien; Verstappen, Frans; Bakker, Carla; Hidding, Alita; Houben, Harry; van der Heijde, Desiree; Landewé, Robert; van der Linden, Sjef

    2002-01-01

    To compare the therapeutic effects of physical fitness training or biofeedback training with the results of usual care in patients with fibromyalgia (FM). One hundred forty-three female patients with FM (American College of Rheumatology criteria) were randomized into 3 groups: a fitness program (n =

  4. Physical activity, mindfulness meditation, or heart rate variability biofeedback for stress reduction: a randomized controlled trial

    NARCIS (Netherlands)

    van der Zwan, J.E.; de Vente, W.; Huizink, A.C.; Bögels, S.M.; de Bruin, E.I.

    2015-01-01

    In contemporary western societies stress is highly prevalent, therefore the need for stress-reducing methods is great. This randomized controlled trial compared the efficacy of self-help physical activity (PA), mindfulness meditation (MM), and heart rate variability biofeedback (HRV-BF) in reducing

  5. Active biofeedback changes the spatial distribution of upper trapezius muscle activity during computer work

    DEFF Research Database (Denmark)

    Samani, Afshin; Holtermann, Andreas; Søgaard, Karen

    2010-01-01

    The aim of this study was to investigate the spatio-temporal effects of advanced biofeedback by inducing active and passive pauses on the trapezius activity pattern using high-density surface electromyography (HD-EMG). Thirteen healthy male subjects performed computer work with superimposed...... benefit of superimposed muscle contraction in relation to the spatial organization of muscle activity during computer work....

  6. Wearable Vibrotactile Biofeedback Device Allowing Identification of Different Floor Conditions for Lower-Limb Amputees.

    Science.gov (United States)

    Wan, Anson H; Wong, Duo W; Ma, Christina Z; Zhang, Ming; Lee, Winson C

    2016-07-01

    To evaluate a newly developed biofeedback device enabling lower-limb amputees to identify various floor conditions. Self-control with repeated measures (with and without the biofeedback device) within the amputee group, and group control comparing between amputee and nonamputee groups. University locomotion laboratory. Five lower-limb amputees and 8 nonamputees (N=13). A wearable biofeedback device, which identified different floor conditions by analyzing the force patterns under the prosthetic feet and provided vibration cues in response to different floor conditions, was provided to the amputees. The subjects stepped on a foam platform concealing a small object or no object at 1 of the 4 locations of the foot sole. Subjects were asked whether there was a small object under their feet and the location of the object if it existed. The test was repeated with 4 different object types and 4 object locations. The success rate of floor identification was evaluated. Without the biofeedback device, nonamputee subjects (76.56%) identified floor conditions better than amputees (22.5%) significantly (Pdevice, the amputees significantly improved (Pdevice, amputees significantly improved their abilities in identifying different floor conditions. Future attempts could configure the device to allow it to provide warning signals in response to fall-inducing conditions. Copyright © 2016 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

  7. Functional chest pain responds to biofeedback treatment but functional heartburn does not: what is the difference?

    Science.gov (United States)

    Shapiro, Michael; Shanani, Ram; Taback, Hanna; Abramowich, Dov; Scapa, Eitan; Broide, Efrat

    2012-06-01

    Patients with functional esophageal disorders represent a challenging treatment group. The purpose of this study was to evaluate the role of biofeedback in the treatment of patients with functional esophageal disorders. In this prospective study, patients with typical/atypical symptoms of gastroesophageal reflux disease underwent upper endoscopy and 24-h pH monitoring. All patients filled out gastroesophageal Reflux Disease Symptom, Hospital Anxiety and Depression, and Symptom Stress Rating questionnaires. Patients with functional heartburn and those with functional chest pain were offered biofeedback treatment. A global assessment questionnaire was filled out at the end of treatment and then 2.8 (range 1-4) years later. From January 2006 to December 2009, 22 patients with functional esophageal diseases were included in the study. Thirteen had functional heartburn and nine had functional chest pain. Six patients from each group received biofeedback treatment. After treatment for 1-4 years, patients with functional chest pain showed significant improvements in symptoms compared with those who were not treated. Patients with functional heartburn showed no improvement. Patients with functional chest pain had a longer time of esophageal acid exposure than those with functional heartburn. Patients with functional chest pain have different central and intraesophageal factors associated with symptom generation in comparison with patients with functional heartburn. Biofeedback is a useful tool in the treatment of patients with functional chest pain, but not for those with functional heartburn.

  8. Cognitive-Behavioral Therapy versus Temporal Pulse Amplitude Biofeedback Training for Recurrent Headache

    Science.gov (United States)

    Martin, Paul R.; Forsyth, Michael R.; Reece, John

    2007-01-01

    Sixty-four headache sufferers were allocated randomly to cognitive-behavioral therapy (CBT), temporal pulse amplitude (TPA) biofeedback training, or waiting-list control. Fifty-one participants (14M/37F) completed the study, 30 with migraine and 21 with tension-type headache. Treatment consisted of 8, 1-hour sessions. CBT was highly effective,…

  9. Meta-Analysis of Biofeedback for Tension-Type Headache: Efficacy, Specificity, and Treatment Moderators

    Science.gov (United States)

    Nestoriuc, Yvonne; Rief, Winfried; Martin, Alexandra

    2008-01-01

    The aims of the present meta-analysis were to investigate the short- and long-term efficacy, multidimensional outcome, and treatment moderators of biofeedback as a behavioral treatment option for tension-type headache. A literature search identified 74 outcome studies, of which 53 were selected according to predefined inclusion criteria.…

  10. [Design of an artificial sphincter system with bio-feedback function based on MSP430].

    Science.gov (United States)

    Wang, Yong-kan; Yan, De-tian

    2005-11-01

    In this paper, we advance a new treating method for rectectomy postoperative anus incontinence, which is called "artificial sphincter system with biofeedback-function". The system simulates the function of human's sphincter and has entered into a stage of simulation experiments on animals.

  11. Evaluation of a Biofeedback Intervention in College Students Diagnosed with Autism Spectrum Disorders

    Science.gov (United States)

    Westlake, Garret

    2013-01-01

    This study used exploratory data analysis (EDA) to examine the use of a biofeedback intervention in the treatment of anxiety for college students diagnosed with an Autism Spectrum Disorder (ASD) (n = 10) and in a typical college population (n = 37). The use of EDA allowed for trends to emerge from the data and provided a foundation for future…

  12. Effects of Biofeedback on Distress in a University Counseling Center: Preliminary Results

    Science.gov (United States)

    Kipper-Smith, Adriana; Tift, Jay H.; Frye, Joan F.

    2016-01-01

    Biofeedback (BF) and its mechanisms of change were examined alongside self-regulation and mind-body approaches in the context of counseling centers. The advance in psychopathology within this context and its intersections with neurophysiological, psychological, and social variables were highlighted. Although BF is commonly provided to students,…

  13. Analysis of different image-based biofeedback models for improving cycling performances

    Science.gov (United States)

    Bibbo, D.; Conforto, S.; Bernabucci, I.; Carli, M.; Schmid, M.; D'Alessio, T.

    2012-03-01

    Sport practice can take advantage from the quantitative assessment of task execution, which is strictly connected to the implementation of optimized training procedures. To this aim, it is interesting to explore the effectiveness of biofeedback training techniques. This implies a complete chain for information extraction containing instrumented devices, processing algorithms and graphical user interfaces (GUIs) to extract valuable information (i.e. kinematics, dynamics, and electrophysiology) to be presented in real-time to the athlete. In cycling, performance indexes displayed in a simple and perceivable way can help the cyclist optimize the pedaling. To this purpose, in this study four different GUIs have been designed and used in order to understand if and how a graphical biofeedback can influence the cycling performance. In particular, information related to the mechanical efficiency of pedaling is represented in each of the designed interfaces and then displayed to the user. This index is real-time calculated on the basis of the force signals exerted on the pedals during cycling. Instrumented pedals for bikes, already designed and implemented in our laboratory, have been used to measure those force components. A group of subjects underwent an experimental protocol and pedaled with (the interfaces have been used in a randomized order) and without graphical biofeedback. Preliminary results show how the effective perception of the biofeedback influences the motor performance.

  14. Audiovisual biofeedback guided breath-hold improves lung tumor position reproducibility and volume consistency

    Directory of Open Access Journals (Sweden)

    Danny Lee, PhD

    2017-07-01

    Conclusions: This study demonstrated that audiovisual biofeedback can be used to improve the reproducibility and consistency of breath-hold lung tumor position and volume, respectively. These results may provide a pathway to achieve more accurate lung cancer radiation treatment in addition to improving various medical imaging and treatments by using breath-hold procedures.

  15. Effects of Biofeedback on Control and Generalization of Nasalization in Typical Speakers

    Science.gov (United States)

    Murray, Elizabeth S. Heller; Mendoza, Joseph O.; Gill, Simone V.; Perkell, Joseph S.; Stepp, Cara E.

    2016-01-01

    Purpose: The purpose of this study was to determine the effects of biofeedback on control of nasalization in individuals with typical speech. Method: Forty-eight individuals with typical speech attempted to increase and decrease vowel nasalization. During training, stimuli consisted of consonant-vowel-consonant (CVC) tokens with the center vowels…

  16. Therapeutic efficacy of neuromuscular electrical stimulation and electromyographic biofeedback on Alzheimer's disease patients with dysphagia.

    Science.gov (United States)

    Tang, Yi; Lin, Xiang; Lin, Xiao-Juan; Zheng, Wei; Zheng, Zhi-Kai; Lin, Zhao-Min; Chen, Jian-Hao

    2017-09-01

    To study the therapeutic effect of neuromuscular electrical stimulation and electromyographic biofeedback (EMG-biofeedback) therapy in improving swallowing function of Alzheimer's disease patients with dysphagia.A series of 103 Alzheimer's disease patients with dysphagia were divided into 2 groups, among which the control group (n = 50) received swallowing function training and the treatment group (n = 53) received neuromuscular electrical stimulation plus EMG-biofeedback therapy. The mini-mental state scale score was performed in all patients along the treatment period. Twelve weeks after the treatment, the swallowing function was assessed by the water swallow test. The nutritional status was evaluated by Mini Nutritional Assessment (MNA) as well as the levels of hemoglobin and serum albumin. The frequency and course of aspiration pneumonia were also recorded.No significant difference on mini-mental state scale score was noted between 2 groups. More improvement of swallowing function, better nutritional status, and less frequency and shorter course of aspiration pneumonia were presented in treatment group when compared with the control group.Neuromuscular electrical stimulation and EMG-biofeedback treatment can improve swallowing function in patients with Alzheimer's disease and significantly reduce the incidence of adverse outcomes. Thus, they should be promoted in clinical practice.

  17. Retroflex Versus Bunched in Treatment for Rhotic Misarticulation: Evidence From Ultrasound Biofeedback Intervention

    Science.gov (United States)

    Byun, Tara McAllister; Hitchcock, Elaine R.; Swartz, Michelle T.

    2014-01-01

    Purpose To document the efficacy of ultrasound biofeedback treatment for misarticulation of the North American English rhotic in children. Because of limited progress in the first cohort, a series of two closely related studies was conducted in place of a single study. The studies differed primarily in the nature of tongue-shape targets (e.g., retroflex, bunched) cued during treatment. Method Eight participants received 8 weeks of individual ultrasound biofeedback treatment targeting rhotics. In Study 1, all 4 participants were cued to match a bunched tongue-shape target. In Study 2, participants received individualized cues aimed at eliciting the tongue shape most facilitative of perceptually correct rhotics. Results Participants in Study 1 showed only minimal treatment effects. In Study 2, all participants demonstrated improved production of rhotics in untreated words produced without biofeedback, with large to very large effect sizes. Conclusions The results of Study 2 indicate that with proper parameters of treatment, ultrasound biofeedback can be a highly effective intervention for children with persistent rhotic errors. In addition, qualitative comparison of Studies 1 and 2 suggests that treatment for the North American English rhotic should include opportunities to explore different tongue shapes, to find the most facilitative variant for each individual speaker. PMID:25088034

  18. Stress relaxation and hillock growth in thin films

    International Nuclear Information System (INIS)

    Jackson, M.S.; Li, C.Y.

    1978-01-01

    The relaxation of thermal stress in a thin film adhering to a substrate of differing expansion coefficient is discussed. Good agreement is found between literature data on relaxation during isothermal anneals of Pb films at up to 350 0 K and model calculations based on a state variable description of plastic flow. The stress system during relaxation is explored, and the absence of diffusional creep is explained. The plasticity-dominated relaxation process suggested by this analysis is shown to be in good qualitative agreement with data on rapid relaxation over the course of a cycle between room and cryogenic temperatures. The implications of this for long-range material transport in the film are discussed. It is shown that hillock volume should increase over the course of a temperature cycle. Finally, a mechanism for hillock nucleation based on grain boundary sliding is suggested

  19. SU-E-J-235: Audiovisual Biofeedback Improves the Correlation Between Internal and External Respiratory Motion

    International Nuclear Information System (INIS)

    Lee, D; Pollock, S; Keall, P; Greer, P; Ludbrook, J; Paganelli, C; Kim, T

    2015-01-01

    Purpose: External respiratory surrogates are often used to predict internal lung tumor motion for beam gating but the assumption of correlation between external and internal surrogates is not always verified resulting in amplitude mismatch and time shift. To test the hypothesis that audiovisual (AV) biofeedback improves the correlation between internal and external respiratory motion, in order to improve the accuracy of respiratory-gated treatments for lung cancer radiotherapy. Methods: In nine lung cancer patients, 2D coronal and sagittal cine-MR images were acquired across two MRI sessions (pre- and mid-treatment) with (1) free breathing (FB) and (2) AV biofeedback. External anterior-posterior (AP) respiratory motions of (a) chest and (b) abdomen were simultaneously acquired with physiological measurement unit (PMU, 3T Skyra, Siemens Healthcare Erlangen, Germany) and real-time position management (RPM) system (Varian, Palo Alto, USA), respectively. Internal superior-inferior (SI) respiratory motions of (c) lung tumor (i.e. centroid of auto-segmented lung tumor) and (d) diaphragm (i.e. upper liver dome) were measured from individual cine-MR images across 32 dataset. The four respiratory motions were then synchronized with the cine-MR image acquisition time. Correlation coefficients were calculated in the time variation of two nominated respiratory motions: (1) chest-abdomen, (2) abdomen-diaphragm and (3) diaphragm-lung tumor. The three combinations were compared between FB and AV biofeedback. Results: Compared to FB, AV biofeedback improved chest-abdomen correlation by 17% (p=0.005) from 0.75±0.23 to 0.90±0.05 and abdomen-diaphragm correlation by 4% (p=0.058) from 0.91±0.11 to 0.95±0.05. Compared to FB, AV biofeedback improved diaphragm-lung tumor correlation by 12% (p=0.023) from 0.65±0.21 to 0.74±0.16. Conclusions: Our results demonstrated that AV biofeedback significantly improved the correlation of internal and external respiratory motion, thus

  20. Biofeedback training effects on minimum toe clearance variability during treadmill walking.

    Science.gov (United States)

    Tirosh, Oren; Cambell, Amity; Begg, Rezaul K; Sparrow, W A

    2013-08-01

    A number of variability analysis techniques, including Poincaré plots and detrended fluctuation analysis (DFA) were used to investigate minimum toe clearance (MTC) control during walking. Ten young adults walked on a treadmill for 10 min at preferred speed in three conditions: (i) no-intervention baseline, (ii) with biofeedback of MTC within a target range, and (iii) no-biofeedback retention. Mean, median, standard deviation (SD), and inter quartile range of MTC during biofeedback (45.57 ± 11.65, 44.98 ± 11.57, 7.08 ± 2.61, 8.58 ± 2.77 mm, respectively) and retention (56.95 ± 20.31, 56.69 ± 20.94, 10.68 ± 5.41, 15.38 ± 10.19 mm) were significantly greater than baseline (30.77 ± 9.49, 30.51 ± 9.49, 3.04 ± 0.77, 3.66 ± 0.91 mm). Relative to baseline, skewness was reduced in biofeedback and retention but only significantly for retention (0.88 ± 0.51, 0.63 ± 0.55, and 0.40 ± 0.40, respectively). Baseline Poincaré measures (SD1 = 0.25, SD2 = 0.34) and DFA (α1 = 0.72 and α2 = 0.64) were lower than biofeedback (SD1 = 0.58, SD2 = 0.83, DFA α1 = 0.76 and α2 = 0.92) with significantly greater variability in retention compared to biofeedback only in the long-term SD2 and α2 analyses. Increased DFA longer-term correlations α2 in retention confirm that a novel gait pattern was acquired with a longer-term variability structure. Short- and long-term variability analyses were both useful in quantifying gait adaptations with biofeedback. The findings provide evidence that MTC can be modified with feedback, suggesting future applications in gait training procedures for impaired populations designed to reduce tripping risk.

  1. SU-E-J-235: Audiovisual Biofeedback Improves the Correlation Between Internal and External Respiratory Motion

    Energy Technology Data Exchange (ETDEWEB)

    Lee, D; Pollock, S; Keall, P [Radiation Physics Laboratory, Sydney Medical School, The University of Sydney, NSW (Australia); Greer, P [School of Mathematical and Physical Sciences, The University of Newcastle, Newcastle, NSW (Australia); Department of Radiation Oncology, Calvary Mater Newcastle, Newcastle, NSW (Australia); Ludbrook, J [Department of Radiation Oncology, Calvary Mater Newcastle, Newcastle, NSW (Australia); Paganelli, C [Dipartimento di Elettronica, Informazione e Bioingegneria, Politecnico di Milano, Milano (Italy); Kim, T [Radiation Physics Laboratory, Sydney Medical School, The University of Sydney, NSW (Australia); Department of Radiation Oncology, University of Virginia Health System, Charlottesville, NC (United States)

    2015-06-15

    Purpose: External respiratory surrogates are often used to predict internal lung tumor motion for beam gating but the assumption of correlation between external and internal surrogates is not always verified resulting in amplitude mismatch and time shift. To test the hypothesis that audiovisual (AV) biofeedback improves the correlation between internal and external respiratory motion, in order to improve the accuracy of respiratory-gated treatments for lung cancer radiotherapy. Methods: In nine lung cancer patients, 2D coronal and sagittal cine-MR images were acquired across two MRI sessions (pre- and mid-treatment) with (1) free breathing (FB) and (2) AV biofeedback. External anterior-posterior (AP) respiratory motions of (a) chest and (b) abdomen were simultaneously acquired with physiological measurement unit (PMU, 3T Skyra, Siemens Healthcare Erlangen, Germany) and real-time position management (RPM) system (Varian, Palo Alto, USA), respectively. Internal superior-inferior (SI) respiratory motions of (c) lung tumor (i.e. centroid of auto-segmented lung tumor) and (d) diaphragm (i.e. upper liver dome) were measured from individual cine-MR images across 32 dataset. The four respiratory motions were then synchronized with the cine-MR image acquisition time. Correlation coefficients were calculated in the time variation of two nominated respiratory motions: (1) chest-abdomen, (2) abdomen-diaphragm and (3) diaphragm-lung tumor. The three combinations were compared between FB and AV biofeedback. Results: Compared to FB, AV biofeedback improved chest-abdomen correlation by 17% (p=0.005) from 0.75±0.23 to 0.90±0.05 and abdomen-diaphragm correlation by 4% (p=0.058) from 0.91±0.11 to 0.95±0.05. Compared to FB, AV biofeedback improved diaphragm-lung tumor correlation by 12% (p=0.023) from 0.65±0.21 to 0.74±0.16. Conclusions: Our results demonstrated that AV biofeedback significantly improved the correlation of internal and external respiratory motion, thus

  2. Hair Dye and Hair Relaxers

    Science.gov (United States)

    ... For Consumers Consumer Information by Audience For Women Hair Dye and Hair Relaxers Share Tweet Linkedin Pin it More sharing ... products. If you have a bad reaction to hair dyes and relaxers, you should: Stop using the ...

  3. Experiments in paramagnetic relaxation

    International Nuclear Information System (INIS)

    Lijphart, E.E.

    1976-01-01

    This thesis presents two attempts to improve the resolving power of the relaxation measurement technique. The first attempt reconsiders the old technique of steady state saturation. When used in conjunction with the pulse technique, it offers the possibility of obtaining additional information about the system in which all-time derivatives are zero; in addition, non-linear effects may be distinguished from each other. The second attempt involved a systematic study of only one system: Cu in the Tutton salts (K and Rb). The systematic approach, the high accuracy of the measurement and the sheer amount of experimental data for varying temperature, magnetic field and concentration made it possible in this case to separate the prevailing relaxation mechanisms reliably

  4. Biofeedback efficacy to improve clinical symptoms and endoscopic signs of solitary rectal ulcer syndrome.

    Science.gov (United States)

    Forootan, Mojgan; Shekarchizadeh, Masood; Farmanara, Hamedreza; Esfahani, Ahmad Reza Shekarchizadeh; Esfahani, Mansooreh Shekarchizadeh

    2018-01-12

    Solitary rectal ulcer syndrome (SRUS) is often resistant to medical and surgical treatment. This study assessed the effect of biofeedback in decreasing the symptoms and the healing of endoscopic signs in SRUS patients. Before starting the treatment, endoscopy and colorectal manometry was performed to evaluate dyssynergic defecation. Patients were followed every four weeks, and during each visit their response to treatment was evaluated regarding to manometry pattern. After at least 50% improvement in manometry parameters, recipients underwent rectosigmoidoscopy. Endoscopic response to biofeedback treatment and clinical symptoms were investigated. Duration of symptoms was 43.11±36.42 months in responder and 63.9 ± 45.74 months in non-responder group (P=0.22). There were more ulcers in non-responder group than responder group (1.50 ±0.71 versus 1.33±- 0.71 before and 1.30 ± 0.95 versus 0.67 ±0.50 after biofeedback), although the difference was not significant (P=0.604, 0.10 respectively). The most prevalent symptoms were constipation (79%), rectal bleeding (68%) and anorectal pain (53%). The most notable improvement in symptoms after biofeedback occured in abdominal pain and incomplete evacuation, and the least was seen in mucosal discharge and toilet waiting as shown in the bar chart. Endoscopic cure was observed in 4 of 10 patients of the non-responder group while 8 patients in responder group experienced endoscopic improvement. It seems that biofeedback has significant effect for pathophysiologic symptoms such as incomplete evacuation and obstructive defecation. Improvement of clinical symptoms does not mean endoscopic cure; so to demonstrate remission the patients have to go under rectosigmoidoscopy.

  5. Biofeedback efficacy to improve clinical symptoms and endoscopic signs of solitary rectal ulcer syndrome

    Directory of Open Access Journals (Sweden)

    Mojgan Forootan

    2018-03-01

    Full Text Available Solitary rectal ulcer syndrome (SRUS is often resistant to medical and surgical treatment. This study assessed the effect of biofeedback in decreasing the symptoms and the healing of endoscopic signs in SRUS patients. Before starting the treatment, endoscopy and colorectal manometry was performed to evaluate dyssynergic defecation. Patients were followed every four weeks, and during each visit their response to treatment was evaluated regarding to manometry pattern. After at least 50% improvement in manometry parameters, recipients underwent rectosigmoidoscopy. Endoscopic response to biofeedback treatment and clinical symptoms were investigated. Duration of symptoms was 43.11±36.42 months in responder and 63.9±45.74 months in non-responder group (P=0.22. There were more ulcers in non-responder group than responder group (1.50±0.71 versus 1.33±-0.71 before and 1.30 ± 0.95 versus 0.67±0.50 after biofeedback, although the difference was not significant (P=0.604, 0.10 respectively. The most prevalent symptoms were constipation (79%, rectal bleeding (68% and anorectal pain (53%. The most notable improvement in symptoms after biofeedback occured in abdominal pain and incomplete evacuation, and the least was seen in mucosal discharge and toilet waiting as shown in the bar chart. Endoscopic cure was observed in 4 of 10 patients of the non-responder group while 8 patients in responder group experienced endoscopic improvement. It seems that biofeedback has significant effect for pathophysiologic symptoms such as incomplete evacuation and obstructive defecation. Improvement of clinical symptoms does not mean endoscopic cure; so to demonstrate remission the patients have to go under rectosigmoidoscopy.

  6. Can biofeedback training of psychophysiological responses enhance athletes' sport performance? A practitioner's perspective.

    Science.gov (United States)

    Pusenjak, Nika; Grad, Anton; Tusak, Matej; Leskovsek, Matevz; Schwarzlin, Romina

    2015-07-01

    In recent years, biofeedback has become increasingly popular for its proven success in peak performance training - the psychophysiological preparation of athletes for high-stakes sport competitions, such as the Olympic games. The aim of this research was to test whether an 8-week period of exposure to biofeedback training could improve the psychophysiological control over competitive anxiety and enhance athletic performance in participating subjects. Participants of this study were highly competent athletes, each training in different sport disciplines. The experimental group consisted of 18 athletes (4 women, 14 men), whereas the Control group had 21 athletes (4 women, 17 men). All athletes were between 16 and 34 years old. The biofeedback device, Nexus 10, was used to detect and measure the psychophysiological responses of athletes. Athletes from both groups (control and experimental) were subjected to stress tests at the beginning of the study and once again at its conclusion. In between, the experimental group received training in biofeedback techniques. We then calculated the overall percentage of athletes in the experimental group compared with those in the control group who were able to control respiration, skin conductance, heart rate, blood flow amplitude, heart rate variability, and heart respiration coherence. One year following completion of the initial study, we questioned athletes from the experimental group, to determine whether they continued to use these skills and if they could detect any subsequent enhancement in their athletic performance. We demonstrated that a greater number of participants in the experimental group were able to successfully control their psychophysiological parameters, in comparison to their peers in the control group. Significant results (p biofeedback - psycho-regulation skills. Furthermore, these participants uniformly reported believing that these skills had enhanced their athletic performance and general well-being.

  7. Relaxation from particle production

    Energy Technology Data Exchange (ETDEWEB)

    Hook, Anson; Marques-Tavares, Gustavo [Stanford Institute for Theoretical Physics, Stanford University, Stanford, CA 94305 (United States)

    2016-12-20

    We consider using particle production as a friction force by which to implement a “Relaxion” solution to the electroweak hierarchy problem. Using this approach, we are able to avoid superplanckian field excursions and avoid any conflict with the strong CP problem. The relaxation mechanism can work before, during or after inflation allowing for inflationary dynamics to play an important role or to be completely decoupled.

  8. Magnetic relaxation in anisotropic magnets

    DEFF Research Database (Denmark)

    Lindgård, Per-Anker

    1971-01-01

    The line shape and the kinematic and thermodynamic slowing down of the critical and paramagnetic relaxation in axially anisotropic materials are discussed. Kinematic slowing down occurs only in the longitudinal relaxation function. The thermodynamic slowing down occurs in either the transverse...... or longitudinal relaxation function depending on the sign of the axial anisotropy....

  9. Momentum constraint relaxation

    International Nuclear Information System (INIS)

    Marronetti, Pedro

    2006-01-01

    Full relativistic simulations in three dimensions invariably develop runaway modes that grow exponentially and are accompanied by violations of the Hamiltonian and momentum constraints. Recently, we introduced a numerical method (Hamiltonian relaxation) that greatly reduces the Hamiltonian constraint violation and helps improve the quality of the numerical model. We present here a method that controls the violation of the momentum constraint. The method is based on the addition of a longitudinal component to the traceless extrinsic curvature A ij -tilde, generated by a vector potential w i , as outlined by York. The components of w i are relaxed to solve approximately the momentum constraint equations, slowly pushing the evolution towards the space of solutions of the constraint equations. We test this method with simulations of binary neutron stars in circular orbits and show that it effectively controls the growth of the aforementioned violations. We also show that a full numerical enforcement of the constraints, as opposed to the gentle correction of the momentum relaxation scheme, results in the development of instabilities that stop the runs shortly

  10. Relaxation peak near 200 K in NiTi alloy

    Science.gov (United States)

    Zhu, J. S.; Schaller, R.; Benoit, W.

    1989-10-01

    Internal friction (IF), frequency ( f), electrical resistance ( R) and zero point movement of the torsion pendulum (ɛ) have been measured in near equi-atomic NiTi alloy in order to clarify the mechanism for the relaxation peak near 200 K. The height of the relaxation peak decreases successively with thermal cycling and settles down to a lower stable value in running 15 cycles. However, the electrical resistance of the sample shows a variation in contrast with the internal friction. Both of them will return to the initial state after a single annealing at 773 K for 1 h. The probable mechanism of this relaxation peak was discussed.

  11. Audiovisual biofeedback breathing guidance for lung cancer patients receiving radiotherapy: a multi-institutional phase II randomised clinical trial.

    Science.gov (United States)

    Pollock, Sean; O'Brien, Ricky; Makhija, Kuldeep; Hegi-Johnson, Fiona; Ludbrook, Jane; Rezo, Angela; Tse, Regina; Eade, Thomas; Yeghiaian-Alvandi, Roland; Gebski, Val; Keall, Paul J

    2015-07-18

    There is a clear link between irregular breathing and errors in medical imaging and radiation treatment. The audiovisual biofeedback system is an advanced form of respiratory guidance that has previously demonstrated to facilitate regular patient breathing. The clinical benefits of audiovisual biofeedback will be investigated in an upcoming multi-institutional, randomised, and stratified clinical trial recruiting a total of 75 lung cancer patients undergoing radiation therapy. To comprehensively perform a clinical evaluation of the audiovisual biofeedback system, a multi-institutional study will be performed. Our methodological framework will be based on the widely used Technology Acceptance Model, which gives qualitative scales for two specific variables, perceived usefulness and perceived ease of use, which are fundamental determinants for user acceptance. A total of 75 lung cancer patients will be recruited across seven radiation oncology departments across Australia. Patients will be randomised in a 2:1 ratio, with 2/3 of the patients being recruited into the intervention arm and 1/3 in the control arm. 2:1 randomisation is appropriate as within the interventional arm there is a screening procedure where only patients whose breathing is more regular with audiovisual biofeedback will continue to use this system for their imaging and treatment procedures. Patients within the intervention arm whose free breathing is more regular than audiovisual biofeedback in the screen procedure will remain in the intervention arm of the study but their imaging and treatment procedures will be performed without audiovisual biofeedback. Patients will also be stratified by treating institution and for treatment intent (palliative vs. radical) to ensure similar balance in the arms across the sites. Patients and hospital staff operating the audiovisual biofeedback system will complete questionnaires to assess their experience with audiovisual biofeedback. The objectives of this

  12. Audiovisual biofeedback breathing guidance for lung cancer patients receiving radiotherapy: a multi-institutional phase II randomised clinical trial

    International Nuclear Information System (INIS)

    Pollock, Sean; O’Brien, Ricky; Makhija, Kuldeep; Hegi-Johnson, Fiona; Ludbrook, Jane; Rezo, Angela; Tse, Regina; Eade, Thomas; Yeghiaian-Alvandi, Roland; Gebski, Val; Keall, Paul J

    2015-01-01

    There is a clear link between irregular breathing and errors in medical imaging and radiation treatment. The audiovisual biofeedback system is an advanced form of respiratory guidance that has previously demonstrated to facilitate regular patient breathing. The clinical benefits of audiovisual biofeedback will be investigated in an upcoming multi-institutional, randomised, and stratified clinical trial recruiting a total of 75 lung cancer patients undergoing radiation therapy. To comprehensively perform a clinical evaluation of the audiovisual biofeedback system, a multi-institutional study will be performed. Our methodological framework will be based on the widely used Technology Acceptance Model, which gives qualitative scales for two specific variables, perceived usefulness and perceived ease of use, which are fundamental determinants for user acceptance. A total of 75 lung cancer patients will be recruited across seven radiation oncology departments across Australia. Patients will be randomised in a 2:1 ratio, with 2/3 of the patients being recruited into the intervention arm and 1/3 in the control arm. 2:1 randomisation is appropriate as within the interventional arm there is a screening procedure where only patients whose breathing is more regular with audiovisual biofeedback will continue to use this system for their imaging and treatment procedures. Patients within the intervention arm whose free breathing is more regular than audiovisual biofeedback in the screen procedure will remain in the intervention arm of the study but their imaging and treatment procedures will be performed without audiovisual biofeedback. Patients will also be stratified by treating institution and for treatment intent (palliative vs. radical) to ensure similar balance in the arms across the sites. Patients and hospital staff operating the audiovisual biofeedback system will complete questionnaires to assess their experience with audiovisual biofeedback. The objectives of this

  13. The impact of audio-visual biofeedback on 4D PET images: Results of a phantom study

    Science.gov (United States)

    Yang, Jaewon; Yamamoto, Tokihiro; Cho, Byungchul; Seo, Youngho; Keall, Paul J.

    2012-01-01

    Purpose: Irregular breathing causes motion blurring artifacts in 4D PET images. Audiovisual (AV) biofeedback has been demonstrated to improve breathing regularity. To investigate the hypothesis that, compared with free breathing, motion blurring artifacts are reduced with AV biofeedback, the authors performed the first experimental phantom-based quantification of the impact of AV biofeedback on 4D PET image quality. Methods: The authors acquired 4D PET dynamic phantom images with AV biofeedback and free breathing by moving a phantom programmed with AV biofeedback trained and free breathing respiratory traces of ten healthy subjects. The authors also acquired stationary phantom images for reference. The phantom was cylindrical with six hollow sphere targets (10, 13, 17, 22, 28, and 37 mm in diameter). The authors quantified motion blurring using the target diameter, Dice coefficient and recovery coefficient (RC) metrics to estimate the effect of motion. Results: The average increase in target diameter for AV biofeedback was 0.6±1.6mm(4.7±13%), which was significantly (pbiofeedback was 0.90±0.07, which was significantly (pbiofeedback were consistently higher than those for free breathing and comparable to those for stationary targets. However, for RCs the impact of target sizes was more dominant than that of motion. In addition, the authors observed large variations in the results with respect to target sizes, subject traces and respiratory bins due to partial volume effects and respiratory motion irregularity. Conclusions: The results indicate that AV biofeedback can significantly reduce motion blurring artifacts and may facilitate improved identification and localization of lung tumors in 4D PET images. The results justify proceeding with clinical studies to quantify the impact of AV biofeedback on 4D PET image quality and tumor detectability. PMID:22320815

  14. Biofeedback therapy combined with diet to treating ODS (Anismus: 2 years outcome

    Directory of Open Access Journals (Sweden)

    Fakhryalsadat Anaraki

    2017-04-01

    Full Text Available Object: The advantages of biofeedback therapy along with diet in patients with constipation are among the issues discussed nowadays. The aim of this study was to evaluate 2 years outcome of biofeedback therapy along with diet in patients with obstructed defecation syndrome (ODS (Anismus. Methodology: The focus of this prospective study is a group of 129 patients with ODS constipation, who were referred to two tertiary-care referral academic centers from 2013 to 2016. Patients received biofeedback therapy combined with appropriate diet in cases group and received diet in controls group. Good response was defined as a subject with at least 50 percent improvement from before to after biofeedback therapy on a Cleveland Clinic Florida Constipation Scoring System (CCF. Factors associated with better outcome were analyzed using SPSS 20 software. Results: Out of the 129 patients, 112 patients (86.8% were female. The mean age of patients was 42.44 ± 15.05 years. The mean CCF score of the patients before and after biofeedback therapy was 12.41 ± 4.39 and 6.00 ± 3.28 respectively in case group (p-value < 0.001. In addition, the mean CCF score of the patients before and after diet therapy was 12.82 ± 4.85 and 9.43 ± 3.79 respectively in control group (p-value < 0.001. While CCF score in both case and control groups reduced significantly after therapy, the rate of this reduction was higher in case group (p < 0.001. Conclusion: Our findings suggest that biofeedback therapy combined with diet will improve patients outcome in ODS constipation. Prospective clinical trials with larger sample sizes are recommend allowing for causal correlations. Resumo: Objetivo: As vantagens da terapia por biofeedback, juntamente com a dieta, em pacientes com constipação se situam entre os tópicos atualmente em discussão. O objetvo desse estudo foi avaliar os resultados, após 2 anos, da terapia por biofeedback associada à dieta em pacientes com s

  15. Effect of biofeedback-assisted autogenic training on headache activity and mood states in Korean female migraine patients.

    Science.gov (United States)

    Kang, Eun-Ho; Park, Joo-Eon; Chung, Chin-Sang; Yu, Bum-Hee

    2009-10-01

    Biofeedback with or without combined autogenic training is known to be effective for the treatment of migraine. This study aimed to examine the effect of biofeedback treatment on headache activity, anxiety, and depression in Korean female patients with migraine headache. Patients were randomized into the treatment group (n=17) and monitoring group (n=15). Mood states including anxiety and depression, and psychophysiological variables such as mean skin temperature of the patients were compared with those of the normal controls (n=21). We found greater treatment response rate (defined as > or =50% reduction in headache index) in patients with biofeedback-assisted autogenic training than in monitoring group. The scores on the anxiety and depression scales in the patients receiving biofeedback-assisted autogenic training decreased after the biofeedback treatment. Moreover, the decrease in their anxiety levels was significantly related to the treatment outcome. This result suggests that the biofeedback-assisted autogenic training is effective for the treatment of migraine and its therapeutic effect is closely related to the improvement of the anxiety level.

  16. Efficacy of biofeedback on quality of life in stages I and II pelvic organ prolapse: A Pilot study.

    Science.gov (United States)

    Ahadi, Tannaz; Taghvadoost, Neda; Aminimoghaddam, Soheila; Forogh, Bijan; Bazazbehbahani, Roxana; Raissi, Gholam Reza

    2017-08-01

    Pelvic organ prolapse (POP) is a prevalent disorder which seriously affects the sufferer's quality of life. The main goal of this study was to evaluate biofeedback impact on quality of life in women with mild to moderate POP. 40 females in stages I and II POP were allocated into 2 groups. One group received pelvic floor muscle exercise and lifestyle advice in addition to biofeedback twice a week for 4 weeks, while the other received a lifestyle advice sheet and pelvic floor muscle exercise without biofeedback. A valid Persian version of P-QOL questionnaire was applied to assess the patients̕ quality of life at baseline, 4 weeks and 12 weeks follow up. Pressure biofeedback and Physical examination were also performed in order to determine pelvic floor muscle strength and staging of the prolapse, respectively. Collected data were analyzed by mixed ANOVA test using SPSS 22. Biofeedback improved the quality of life in seven of nine P-QOL domains. However, it had no significant impact either on pelvic floor muscle strength or on the stage of the prolapse. Biofeedback could be considered as a non-invasive treatment leading to quality of life promotion in women with stages I and II POP. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. Effective temperature in relaxation of Coulomb glasses.

    Science.gov (United States)

    Somoza, A M; Ortuño, M; Caravaca, M; Pollak, M

    2008-08-01

    We study relaxation in two-dimensional Coulomb glasses up to macroscopic times. We use a kinetic Monte Carlo algorithm especially designed to escape efficiently from deep valleys around metastable states. We find that, during the relaxation process, the site occupancy follows a Fermi-Dirac distribution with an effective temperature much higher than the real temperature T. Long electron-hole excitations are characterized by T(eff), while short ones are thermalized at T. We argue that the density of states at the Fermi level is proportional to T(eff) and is a good thermometer to measure it. T(eff) decreases extremely slowly, roughly as the inverse of the logarithm of time, and it should affect hopping conductance in many experimental circumstances.

  18. Dispersion of Sound in Dilute Suspensions with Nonlinear Particle Relaxation

    Science.gov (United States)

    Kandula, Max

    2010-01-01

    The theory accounting for nonlinear particle relaxation (viscous and thermal) has been applied to the prediction of dispersion of sound in dilute suspensions. The results suggest that significant deviations exist for sound dispersion between the linear and nonlinear theories at large values of Omega(Tau)(sub d), where Omega is the circular frequency, and Tau(sub d) is the Stokesian particle relaxation time. It is revealed that the nonlinear effect on the dispersion coefficient due to viscous contribution is larger relative to that of thermal conduction

  19. Variational formulation of relaxed and multi-region relaxed magnetohydrodynamics

    Science.gov (United States)

    Dewar, R. L.; Yoshida, Z.; Bhattacharjee, A.; Hudson, S. R.

    2015-12-01

    > Ideal magnetohydrodynamics (IMHD) is strongly constrained by an infinite number of microscopic constraints expressing mass, entropy and magnetic flux conservation in each infinitesimal fluid element, the latter preventing magnetic reconnection. By contrast, in the Taylor relaxation model for formation of macroscopically self-organized plasma equilibrium states, all these constraints are relaxed save for the global magnetic fluxes and helicity. A Lagrangian variational principle is presented that leads to a new, fully dynamical, relaxed magnetohydrodynamics (RxMHD), such that all static solutions are Taylor states but also allows state with flow. By postulating that some long-lived macroscopic current sheets can act as barriers to relaxation, separating the plasma into multiple relaxation regions, a further generalization, multi-region relaxed magnetohydrodynamics (MRxMHD) is developed.

  20. Dynamics of relaxed inflation

    Science.gov (United States)

    Tangarife, Walter; Tobioka, Kohsaku; Ubaldi, Lorenzo; Volansky, Tomer

    2018-02-01

    The cosmological relaxation of the electroweak scale has been proposed as a mechanism to address the hierarchy problem of the Standard Model. A field, the relaxion, rolls down its potential and, in doing so, scans the squared mass parameter of the Higgs, relaxing it to a parametrically small value. In this work, we promote the relaxion to an inflaton. We couple it to Abelian gauge bosons, thereby introducing the necessary dissipation mechanism which slows down the field in the last stages. We describe a novel reheating mechanism, which relies on the gauge-boson production leading to strong electro-magnetic fields, and proceeds via the vacuum production of electron-positron pairs through the Schwinger effect. We refer to this mechanism as Schwinger reheating. We discuss the cosmological dynamics of the model and the phenomenological constraints from CMB and other experiments. We find that a cutoff close to the Planck scale may be achieved. In its minimal form, the model does not generate sufficient curvature perturbations and additional ingredients, such as a curvaton field, are needed.

  1. Análise da resposta ao biofeedback nos pacientes com incontinência fecal Analysis of biofeedback for fecal incontinence

    Directory of Open Access Journals (Sweden)

    André Figueiredo Accetta

    2011-06-01

    Full Text Available Incontinência fecal é uma condição com importante impacto na qualidade de vida, e inúmeras formas de tratamento são descritas. Objetivo: Avaliar a resposta ao tratamento por biofeedback e o perfil epidemiológico dos pacientes com incontinência fecal, descrevendo os critérios de seleção e a técnica utilizada. Métodos: Estudo retrospectivo dos pacientes tratados em três anos (junho de 2005 a junho de 2008. Resultados: Trinta pacientes, sendo 26 mulheres e 4 homens, com idade média de 66 anos. O número de gestações e partos normais variou de nenhuma a seis e a histerectomia esteve presente em nove casos. Todos os pacientes apresentavam hipotonia na manometria. Dezoito pacientes ficaram satisfeitos com o tratamento proposto, dez ficaram parcialmente satisfeitos, nenhum ficou completamente insatisfeito, e dois abandonaram a terapia. Conclusão: O tratamento clínico associado ao biofeedback pode ser eficaz para a melhoria dos sintomas; entretanto, o entendimento e compreensão do problema por parte do paciente parece ser o efeito mais importante para esses resultados. A presença de diabetes mellitus, cirurgias orificiais e histerectomia podem ter relação com as queixas de incontinência.Fecal incontinence is a disabling condition with relevant social costs. Many therapies are described. Objective: To evaluate the response to biofeedback and epidemiological profile, describing the used technique. Methods: A retrospective study in 3 years (June 2005 - June 2008. Results: Thirty patients, 26 women and 4 men, with an average age of 66. The number of normal pregnancies and births varied from none to six and hysterectomy was present in nine. Hypotonia in manometry was present in all patients. Eighteen patients were satisfied, ten were partially met, none was completely dissatisfied, and two have abandoned the therapy. Conclusion: The clinical therapy to biofeedback can be effective for incontinence, but the comprehension by patient

  2. Characterizing the Learning Effect in Response to Biofeedback Aimed at Reducing Tibial Acceleration during Running

    Directory of Open Access Journals (Sweden)

    Linda M. A. van Gelder

    2018-02-01

    Full Text Available Increased tibial acceleration has been found to be an important risk factor for tibial stress fractures. Interventions aimed at reducing this variable which found a beneficial effect include the use of biofeedback in gait retraining. However, no studies have focused on the time participants take to modify tibial acceleration, therefore we aimed to find the start of a learning plateau in this study. Six participants ran on a treadmill while multisensory feedback was given. A single-subject analysis was used to characterise the learning effects. All participants changed peak tibial acceleration within the first step of running in the feedback condition. Two participants further reduced tibial acceleration to reach a plateau within 120 steps. In four of the six participants a strong effect of the feedback was still present after a week. Further research is needed to optimise the use of biofeedback in reducing the prevalence of tibial stress fractures.

  3. A Robot-Based Tool for Physical and Cognitive Rehabilitation of Elderly People Using Biofeedback

    Science.gov (United States)

    Lopez-Samaniego, Leire; Garcia-Zapirain, Begonya

    2016-01-01

    This publication presents a complete description of a technological solution system for the physical and cognitive rehabilitation of elderly people through a biofeedback system, which is combined with a Lego robot. The technology used was the iOS’s (iPhone Operating System) Objective-C programming language and its XCode programming environment; and SQLite in order to create the database. The biofeedback system is implemented by the use of two biosensors which are, in fact, a Microsoft band 2 in order to register the user’s heart rate and a MYO sensor to detect the user’s arm movement. Finally, the system was tested with seven elderly people from La Santa y Real Casa de la Misericordia nursing home in Bilbao. The statistical assessment has shown that the users are satisfied with the usability of the system, with a mean score of 79.29 on the System Usability Scale (SUS) questionnaire. PMID:27886146

  4. BIOFEEDBACK Y DEPORTES: POTENCIALES L͍NEAS DE ACTUACIÓN

    Directory of Open Access Journals (Sweden)

    J. F. Godoy

    2010-07-01

    Full Text Available

    En este trabajo se presentan potenciales líneas de integración del biofeedback en el área de la actividad física y deportiva, revisando tres posibles áreas de actuación en el deporte utilizando procedimientos o técnicas de biofeedback: a mejora en el entrenamiento deportivo u optimización del proceso de preparación física del deportista, b mejora de la actuación deportiva u optimización del rendimiento del deportista y c prevención y rehabilitación de lesiones generadas por la práctica deportiva.

     

  5. A wearable biofeedback control system based body area network for freestyle swimming.

    Science.gov (United States)

    Rui Li; Zibo Cai; WeeSit Lee; Lai, Daniel T H

    2016-08-01

    Wearable posture measurement units are capable of enabling real-time performance evaluation and providing feedback to end users. This paper presents a wearable feedback prototype designed for freestyle swimming with focus on trunk rotation measurement. The system consists of a nine-degree-of-freedom inertial sensor, which is built in a central data collection and processing unit, and two vibration motors for delivering real-time feedback. Theses devices form a fundamental body area network (BAN). In the experiment setup, four recreational swimmers were asked to do two sets of 4 x 25m freestyle swimming without and with feedback provided respectively. Results showed that real-time biofeedback mechanism improves swimmers kinematic performance by an average of 4.5% reduction in session time. Swimmers can gradually adapt to feedback signals, and the biofeedback control system can be employed in swimmers daily training for fitness maintenance.

  6. Biofeedback-guided pelvic floor exercise therapy for obstructive defecation: An effective alternative

    Science.gov (United States)

    ba-bai-ke-re, Ma-Mu-Ti-Jiang A; Wen, Ni-Re; Hu, Yun-Long; Zhao, Liang; Tuxun, Tuerhongjiang; Husaiyin, Aierhati; Sailai, Yalikun; Abulimiti, Alimujiang; Wang, Yun-Hai; Yang, Peng

    2014-01-01

    AIM: To compare biofeedback-guided pelvic floor exercise therapy (BFT) with the use of oral polyethylene glycol (PEG) for the treatment of obstructive defecation. METHODS: A total of 88 subjects were assigned to treatment with either BFT (n = 44) or oral PEG (n = 44). Constipation symptoms (including difficult evacuation, hard stool, digitation necessity, incomplete emptying sensation, laxative dependence, perianal pain at defecation, and constipation satisfaction), Wexner Scores, and quality of life scores were assessed after 1, 3, and 6 mo. RESULTS: At the 6 mo follow-up, the symptoms of the BFT group patients showed significantly greater improvements compared with the PEG group regarding difficult evacuation, hard stools, digitation necessity, laxative dependence, perianal pain at defecation, constipation satisfaction, Wexner Constipation Score, and quality of life score (P biofeedback-guided pelvic floor exercise training is superior to oral polyethylene glycol therapy for obstructive defecation. PMID:25083090

  7. Heart-pulse Biofeedback in Playful Exercise using a Wearable device and Modular Interactive Tiles

    DEFF Research Database (Denmark)

    Shimokakimoto, Tomoya; Lund, Henrik Hautop; Suzuki, Kenji

    2014-01-01

    interactive tiles. The system consists of a wearable device that measures heart-pulse via ear-mounted sensor, and modular interactive tiles which are used for physical rehabilitation exercise through playing a game. The wearable devise enables detection of heart pulse in real-time and therefore provides heart...... beat rate during playful activities, even if the heart pulse wave have motion artifacts. The tiles are designed to build flexible structures and to provide immediate feedback based on the users’ physical interaction with the tiles. We combine the two systems to provide users with heart pulse...... biofeedback in playful exercise. We show that using the developed system it is possible for the users to regulate the exercise intensity on their own with biofeedback, and also possible to analyze exercise activity using number of steps on the tiles and heart beat rate....

  8. Effect of visual biofeedback cycling training on gait in patients with multiple sclerosis.

    Science.gov (United States)

    Hochsprung, A; Granja Domínguez, A; Magni, E; Escudero Uribe, S; Moreno García, A

    2017-09-06

    Gait alterations are present in a high percentage of patients with multiple sclerosis (MS). They appear from early stages of the disease and can limit patients' capacity to perform basic activities of daily living, affecting their quality of life. Visual biofeedback cycling training appears to be a useful tool in treating these impairments. This study aims to evaluate the short-term effect of visual biofeedback cycling training on gait in patients with MS. A total of 61 patients with mild to moderate MS were randomly assigned to a control group and an intervention group. The intervention group received visual biofeedback cycling training (MOTOmed viva2 system) once per week for 3 months, and a home exercise program. The control group only received the home exercise program. Both groups were evaluated using the GAITRite ® Walkway gait assessment system before the intervention, during the first month of the programme, and after the intervention. In the intervention group, the analysis revealed statistically significant differences between Functional Ambulation Profile (FAP) scores before and during the intervention (P=.014), and before and after the intervention (P=.002). A statistically significant improvement was observed in step length in the intervention group between pre- and post-intervention scores (P=.001) and between first-month and post-intervention scores (P=.004). Visual biofeedback cycling training improved specific gait parameters in the short term and appears to be a therapeutic option for gait retraining in patients with MS. Copyright © 2017 Sociedad Española de Neurología. Publicado por Elsevier España, S.L.U. All rights reserved.

  9. Biofeedback for treatment of awake and sleep bruxism in adults: systematic review protocol

    OpenAIRE

    Ilovar, Sasa; Zolger, Danaja; Castrillon, Eduardo; Car, Josip; Huckvale, Kit

    2014-01-01

    Background Bruxism is a disorder of jaw-muscle activity characterised by repetitive clenching or grinding of the teeth which results in discomfort and damage to dentition. The two clinical manifestations of the condition (sleep and awake bruxism) are thought to have unrelated aetiologies but are palliated using similar techniques. The lack of a definitive treatment has prompted renewed interest in biofeedback, a behaviour change method that uses electronic detection to provide a stimulus when...

  10. Design and Evaluation of Photo-Induced Biofeedback Fabric for the Enhancement in Sleeping Sense

    OpenAIRE

    Chu, Wei-Cheng; Lin, Hsin-Ju; Chiu, Shu-Ping

    2013-01-01

    Based on overcoming the sleeping obstacle for people, the purpose of this study is to design a photo-induced biofeedback fabric which is a kind of optical fiber fabric with the function of enhancing sleeping sense and to evaluate its effect. The fabrics with two layers including background layer and pattern layer were designed firstly. The pattern layers with 3 kinds of wavelengths of sine waves and the light controller with 3 kinds of flashing frequencies were then prepared. Guiding the ligh...

  11. STRUCTURAL STRESS RELAXATION IN STAINLESS INSTABILITY STEEL

    Directory of Open Access Journals (Sweden)

    S. Lyabuk

    2017-06-01

    Full Text Available The approach to the description of conditions of martensitic transformation in austenitic steel is advanced. Transformation induced hardening is the result of Le Chatelier principle in instability alloys. The phase transformation in austenitic instability stainless steel is the cause of reduction of grain refining and increase of strength. It was experimentally shown that physical-mechanical characteristics of the prepared materials were defined by the structure and inhomogeneous distribution of the hardening phase within a grain. The reasons for high thermal stability of inverse austenitic were established. The factors determining the inverse austenitic relaxation resistibility and resources for its increasing were revealed.

  12. The effect of nasopharyngoscopic biofeedback in patients with cleft palate and velopharyngeal dysfunction.

    Science.gov (United States)

    Brunner, Monika; Stellzig-Eisenhauer, Angelika; Pröschel, Ute; Verres, Rolf; Komposch, Gerda

    2005-11-01

    To evaluate the immediate, long-term, and carry-over effects of nasopharyngoscopic biofeedback therapy in patients with cleft palate who exhibit velopharyngeal dysfunction (VPD). Pre- versus posttreatment and follow-up comparisons. Cleft palate center of the Heidelberg University Hospital, Heidelberg, Germany. Eleven patients with VPD who had received conventional speech therapy without showing significant improvement. A four-stage feedback procedure. The patients watched and evaluated their velopharyngeal (VP) valving during speech by an endoscopic image displayed on a video monitor. Two feedback sessions took place for every target sound. Mean occurrence of VP closure during speech sound production on different linguistic levels. Patients' self-perception was assessed by a questionnaire and speech diary. Significant improvement and stability of VP closure was noted. Mean occurrence of VP closure was 5% before therapy, 91% after two biofeedback sessions, and 86% in the follow-up after 6 months. Velopharyngeal dysfunction associated with compensatory articulation proved to be equally well trained as VPD on sounds with good articulatory placement. No significant difference was observed in the degree of improvement between phoneme-specific VPD and generalized VPD. The transfer to the level of words and sentences was successful and showed significant stability. The stability of VP closure for vowels was less than the stability for fricatives and stop sounds. Patients gained improved auditory and kinesthetic self-perception of their articulation. Nasopharyngoscopic biofeedback therapy proves to be a quick and effective method to change VPD. It shows stable results and carry-over effects.

  13. Effect of Heart Rate Variability Biofeedback on Sport Performance, a Systematic Review.

    Science.gov (United States)

    Jiménez Morgan, Sergio; Molina Mora, José Arturo

    2017-09-01

    Aim is to determine if the training with heart rate variability biofeedback allows to improve performance in athletes of different disciplines. Methods such as database search on Web of Science, SpringerLink, EBSCO Academic Search Complete, SPORTDiscus, Pubmed/Medline, and PROQUEST Academic Research Library, as well as manual reference registration. The eligibility criteria were: (a) published scientific articles; (b) experimental studies, quasi-experimental, or case reports; (c) use of HRV BFB as main treatment; (d) sport performance as dependent variable; (e) studies published until October 2016; (f) studies published in English, Spanish, French or Portuguese. The guidelines of the PRISMA statement were followed. Out of the 451 records found, seven items were included. All studies had a small sample size (range from 1 to 30 participants). In 85.71% of the studies (n = 6) the athletes enhanced psychophysiological variables that allowed them to improve their sport performance thanks to training with heart rate variability biofeedback. Despite the limited amount of experimental studies in the field to date, the findings suggest that heart rate variability biofeedback is an effective, safe, and easy-to-learn and apply method for both athletes and coaches in order to improve sport performance.

  14. Neuroplus biofeedback improves attention, resilience, and injury prevention in elite soccer players.

    Science.gov (United States)

    Rusciano, Aiace; Corradini, Giuliano; Stoianov, Ivilin

    2017-06-01

    Performance and injury prevention in elite soccer players are typically investigated from physical-tactical, biomechanical, and metabolic perspectives. However, executive functions, visuospatial abilities, and psychophysiological adaptability or resilience are also fundamental for efficiency and well-being in sports. Based on previous research associating autonomic flexibility with prefrontal cortical control, we designed a novel integrated autonomic biofeedback training method called Neuroplus to improve resilience, visual attention, and injury prevention. Herein, we introduce the method and provide an evaluation of 20 elite soccer players from the Italian Soccer High Division (Serie-A): 10 players trained with Neuroplus and 10 trained with a control treatment. The assessments included psychophysiological stress profiles, a visual search task, and indexes of injury prevention, which were measured pre- and posttreatment. The analysis showed a significant enhancement of physiological adaptability, recovery following stress, visual selective attention, and injury prevention that were specific to the Neuroplus group. Enhancing the interplay between autonomic and cognitive functions through biofeedback may become a key principle for obtaining excellence and well-being in sports. To our knowledge, this is the first evidence that shows improvement in visual selective attention following intense autonomic biofeedback. © 2017 Society for Psychophysiological Research.

  15. Visual Biofeedback Balance Training Using Wii Fit after Stroke: A Randomized Controlled Trial

    Science.gov (United States)

    Barcala, Luciana; Grecco, Luanda André Collange; Colella, Fernanda; Lucareli, Paulo Roberto Garcia; Salgado, Afonso Shiguemi Inoue; Oliveira, Claudia Santos

    2013-01-01

    [Purpose] The aim of the present study was to investigate the effect of balance training with visual biofeedback on balance, body symmetry, and function among individuals with hemiplegia following a stroke. [Subjects and Methods] The present study was performed using a randomized controlled clinical trial with a blinded evaluator. The subjects were twenty adults with hemiplegia following a stroke. The experimental group performed balance training with visual biofeedback using Wii Fit® together with conventional physical therapy. The control group underwent conventional physical therapy alone. The intervention lasted five weeks, with two sessions per week. Body symmetry (baropodometry), static balance (stabilometry), functional balance (Berg Balance Scale), functional mobility (Timed Up and Go test), and independence in activities of daily living (Functional Independence Measure) were assessed before and after the intervention. [Results] No statistically significant differences were found between the experimental and control groups. In the intragroup analysis, both groups demonstrated a significant improvement in all variables studied. [Conclusion] The physical therapy program combined with balance training involving visual biofeedback (Wii Fit®) led to an improvement in body symmetry, balance, and function among stroke victims. However, the improvement was similar to that achieved with conventional physical therapy alone. PMID:24259909

  16. Biofeedback Therapy Effect on Facial Nerve Palsy and Prevention of Synkinesis

    Directory of Open Access Journals (Sweden)

    Abbas ali Pour-Momeny

    2011-04-01

    Full Text Available Objective: Synkiesia is a sequel of facial nerve palsy. It usually begins 3-4 months after axonal regeneration and progressed up to two years afterward. Treatment of synkinesia is very difficult and sometimes impossible.The aim of our study is find a better procedure to treat facial nerve palsy and prevent synkinesia. Materials and Methods: Twenty nine patients with facial nerve palsy were selected by electrodiagnosis tests. They were divided in two groups. The experimental group was treated by biofeedback electromyography and the second group was treated by common physiotherapy. The evaluation of all patients was done by Photoshop assessment and facial grading scale before and after treatment. Result: After the treatment, a significant general improvement was observed in both groups (p<0.05, but in experimental group (biofeedback showed better result than the other one. The number of patients with synkinesia as well as the severity of their synkinesis in experimental group were lesser than the other one. Conclusion: Biofeedback therapy is more efficient than common physiotherapy.By using this approach, control and reducing synkinesia is more feasible. Assessment by Pohotoshop procedure showed better accuracy than facial grading scale.

  17. Response of spinal myoclonus to a combination therapy of autogenic training and biofeedback

    Directory of Open Access Journals (Sweden)

    Kempuraj Duraisamy

    2007-10-01

    Full Text Available Abstract Introduction Clinical evidence indicates that certain types of movement disorders are due to psychosomatic factors. Patients with myoclonic movements are usually treated by a variety of therapeutic agents. Autogenic training (AT, a recognized form of psychosomatic therapies, is suitable for certain types of neurological diseases. We describe a patient with myoclonus who failed to respond to conventional medical therapy. His symptoms were exaggerated by psychogenic factors, especially anger. Case presentation A 42-year-old man was admitted to our hospital, Preventive Welfare Clinic, for severe paroxysmal axial myoclonus of the left shoulder and abdominal muscles. The initial diagnosis was "combination of spinal segmental myoclonus and propriospinal myoclonus". The myoclonic movements did not occur during sleep but were aggravated by bathing, alcohol drinking, and anger. Psychological examination indicated hostile attribution. Although considered not to be a case of psychogenic myoclonus, a "psychogenic factor" was definitely involved in the induction of the organic myoclonus. The final diagnosis was "combination of spinal segmental myoclonus and propriospinal myoclonus accompanied by features of psychosomatic disorders". The patient underwent psychosomatic therapy including AT and surface electromyography (EMG-biofeedback therapy and treatment with clonazepam and carbamazepine. Results AT and EMG-biofeedback resulted in shortening the duration and reducing the amplitude and frequency of the myoclonic discharges. Conclusion Psychosomatic therapy with AT and surface EMG-biofeedback produced excellent improvement of myoclonic movements and allowed the reduction of the dosage of conventional medications.

  18. Response of spinal myoclonus to a combination therapy of autogenic training and biofeedback.

    Science.gov (United States)

    Sugimoto, Koreaki; Theoharides, Theoharis C; Kempuraj, Duraisamy; Conti, Pio

    2007-10-12

    Clinical evidence indicates that certain types of movement disorders are due to psychosomatic factors. Patients with myoclonic movements are usually treated by a variety of therapeutic agents. Autogenic training (AT), a recognized form of psychosomatic therapies, is suitable for certain types of neurological diseases. We describe a patient with myoclonus who failed to respond to conventional medical therapy. His symptoms were exaggerated by psychogenic factors, especially anger. A 42-year-old man was admitted to our hospital, Preventive Welfare Clinic, for severe paroxysmal axial myoclonus of the left shoulder and abdominal muscles. The initial diagnosis was "combination of spinal segmental myoclonus and propriospinal myoclonus". The myoclonic movements did not occur during sleep but were aggravated by bathing, alcohol drinking, and anger. Psychological examination indicated hostile attribution. Although considered not to be a case of psychogenic myoclonus, a "psychogenic factor" was definitely involved in the induction of the organic myoclonus. The final diagnosis was "combination of spinal segmental myoclonus and propriospinal myoclonus accompanied by features of psychosomatic disorders". The patient underwent psychosomatic therapy including AT and surface electromyography (EMG)-biofeedback therapy and treatment with clonazepam and carbamazepine. AT and EMG-biofeedback resulted in shortening the duration and reducing the amplitude and frequency of the myoclonic discharges. Psychosomatic therapy with AT and surface EMG-biofeedback produced excellent improvement of myoclonic movements and allowed the reduction of the dosage of conventional medications.

  19. Pattern analysis of defecography in patients with chronic functional constipation: is it predictable for the responsiveness of biofeedback therapy?

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Hye Rin; Kim, Ah Young; Hong, Seong Sook; Byun, Jae Ho; Myung Seung Jae; Ha, Hyun Kwon [University of Ulsan of Medicine, Seoul (Korea, Republic of)

    2005-08-15

    To determine of pattern analysis of defecography can predict the responsiveness of biofeedback therapy in patients with chronic functional constipation. Over a two-year period, 104 patients with chronic functional constipation underwent defecography and biofeedback therapy. Two blinded readers analyzed the defecographic findings and classified them into six types; I = normal defecation, II = hypertonic lower anal sphincter (poor anal opening due to a persistent contraction of the lower anal sphincter), III dyskinetic puborectal sling (inadequate laxity of the puborectal sling), IV spastic pelvic floor syndrome (persistent contraction of both the puborectal sling and the lower and sphincter), V unclassified (including paradoxical contraction of the anal sphincter), VI anatomical obstruction. In addition, the degree of rectal contraction during defecation was scored (grade 0 to 3). After biofeedback therapy, the differences in the defecography patterns or rectal contraction between the two groups, the responsive or non-responsive group, were analyzed. The defecograms revealed that the type IV of the spastic pelvic floor syndrome was most common (50 of 104 patients, 48%), followed by II (21/104, 20%), III (12/104, 11.5%), V (9/104, 9%) and VI (12/104, 11.5%). Biofeedback therapy showed a therapeutic response in 71 out of 104 patients (68%) but failed in 33 patients (32%). However, there were no significant differences in the defecographic pattern between the responsive and non-responsive groups ({rho} = 0.630). The defecograms revealed contractions in 78 patients (75%) and moderate to vigorous contractions (more than grade 2) in 66 patients. Most of the biofeedback-responsive group showed rectal contractions (66 of 71 patients, 93%, {rho} < 0.001). In patients with chronic functional constipation, there was no significant difference in the morphological patterns of the defecogram between the responsive and non-responsive biofeedback groups. However, the presence of

  20. Pattern analysis of defecography in patients with chronic functional constipation: is it predictable for the responsiveness of biofeedback therapy?

    International Nuclear Information System (INIS)

    Yang, Hye Rin; Kim, Ah Young; Hong, Seong Sook; Byun, Jae Ho; Myung Seung Jae; Ha, Hyun Kwon

    2005-01-01

    To determine of pattern analysis of defecography can predict the responsiveness of biofeedback therapy in patients with chronic functional constipation. Over a two-year period, 104 patients with chronic functional constipation underwent defecography and biofeedback therapy. Two blinded readers analyzed the defecographic findings and classified them into six types; I = normal defecation, II = hypertonic lower anal sphincter (poor anal opening due to a persistent contraction of the lower anal sphincter), III dyskinetic puborectal sling (inadequate laxity of the puborectal sling), IV spastic pelvic floor syndrome (persistent contraction of both the puborectal sling and the lower and sphincter), V unclassified (including paradoxical contraction of the anal sphincter), VI anatomical obstruction. In addition, the degree of rectal contraction during defecation was scored (grade 0 to 3). After biofeedback therapy, the differences in the defecography patterns or rectal contraction between the two groups, the responsive or non-responsive group, were analyzed. The defecograms revealed that the type IV of the spastic pelvic floor syndrome was most common (50 of 104 patients, 48%), followed by II (21/104, 20%), III (12/104, 11.5%), V (9/104, 9%) and VI (12/104, 11.5%). Biofeedback therapy showed a therapeutic response in 71 out of 104 patients (68%) but failed in 33 patients (32%). However, there were no significant differences in the defecographic pattern between the responsive and non-responsive groups (ρ = 0.630). The defecograms revealed contractions in 78 patients (75%) and moderate to vigorous contractions (more than grade 2) in 66 patients. Most of the biofeedback-responsive group showed rectal contractions (66 of 71 patients, 93%, ρ < 0.001). In patients with chronic functional constipation, there was no significant difference in the morphological patterns of the defecogram between the responsive and non-responsive biofeedback groups. However, the presence of rectal

  1. Anomalous relaxation and self-organization in non-equilibrium processes

    OpenAIRE

    Fatkullin, Ibrahim; Kladko, Konstantin; Mitkov, Igor; Bishop, A. R.

    2000-01-01

    We study thermal relaxation in ordered arrays of coupled nonlinear elements with external driving. We find, that our model exhibits dynamic self-organization manifested in a universal stretched-exponential form of relaxation. We identify two types of self-organization, cooperative and anti-cooperative, which lead to fast and slow relaxation, respectively. We give a qualitative explanation for the behavior of the stretched exponent in different parameter ranges. We emphasize that this is a sys...

  2. The impact of thermal wave characteristics on thermal dose distribution during thermal therapy: A numerical study

    International Nuclear Information System (INIS)

    Shih, T.-C.; Kou, H.-S.; Liauh, C.-T.; Lin, W.-L.

    2005-01-01

    The aim of this study was to investigate the effects of the propagation speed of a thermal wave in terms of the thermal relaxation time on the temperature/thermal dose distributions in living tissue during thermal therapies. The temperature field in tissue was solved by the finite difference method, and the thermal dose was calculated from the formulation proposed by Sapareto and Dewey [Int. J. Radiat. Oncol. Biol. Phys. 10, 787-800 (1984)]. Under the same total deposited energy, for a rapid heating process the time lagging behavior of the peak temperature became pronounced and the level of the peak temperature was decreased with increasing the thermal relaxation time. When the heating duration was longer than the thermal relaxation time of tissues, there was no significant difference between the thermal dose distributions with/without considering the effect of the thermal relaxation time. In other words, when the heating duration is comparable to or shorter than the thermal relaxation time of tissue, the results of the wave bioheat transfer equation (WBHTE) are fully different from that of the Pennes' bioheat transfer equation (PBHTE). Besides, for a rapid heating process the dimension of thermal lesion was still significantly affected by perfusion, because this is what is predicted by the WBHTE but not by the PBHTE, i.e., the wave feature of the temperature field cannot fully be predicted by the PBHTE

  3. The effect of the Magnus force on skyrmion relaxation dynamics

    OpenAIRE

    Brown, Barton L.; Täuber, Uwe C.; Pleimling, Michel

    2018-01-01

    We perform systematic Langevin molecular dynamics simulations of interacting skyrmions in thin films. The interplay between Magnus force, repulsive skyrmion-skyrmion interaction and thermal noise yields different regimes during non-equilibrium relaxation. In the noise-dominated regime the Magnus force enhances the disordering effects of the thermal noise. In the Magnus-force-dominated regime, the Magnus force cooperates with the skyrmion-skyrmion interaction to yield a dynamic regime with slo...

  4. Biofeedback for treatment of awake and sleep bruxism in adults: systematic review protocol.

    Science.gov (United States)

    Ilovar, Sasa; Zolger, Danaja; Castrillon, Eduardo; Car, Josip; Huckvale, Kit

    2014-05-02

    Bruxism is a disorder of jaw-muscle activity characterised by repetitive clenching or grinding of the teeth which results in discomfort and damage to dentition. The two clinical manifestations of the condition (sleep and awake bruxism) are thought to have unrelated aetiologies but are palliated using similar techniques. The lack of a definitive treatment has prompted renewed interest in biofeedback, a behaviour change method that uses electronic detection to provide a stimulus whenever bruxism occurs. This systematic review aims to provide a comprehensive overview of the state of research into biofeedback for bruxism; to assess the efficacy and acceptability of biofeedback therapy in management of awake bruxism and, separately, sleep bruxism in adults; and to compare findings between the two variants. A systematic review of published literature examining biofeedback as an intervention directed at controlling primary bruxism in adults. We will search electronic databases and the grey literature using a predefined search strategy to identify randomised and non-randomised studies, technical reports and patents. Searches will not be restricted by language or date and will be expanded through contact with authors and experts, and by following up reference lists and citations. Two authors, working independently, will conduct screening of search results, study selection, data extraction and quality assessment and a third will resolve any disagreements. The primary outcomes of acceptability and effectiveness will be assessed using only randomised studies, segregated by bruxism subtype. A meta-analysis of these data will be conducted only if pre-defined conditions for quality and heterogeneity are met, otherwise the data will be summarized in narrative form. Data from non-randomised studies will be used to augment a narrative synthesis of the state of technical developments and any safety-related issues. PROSPERO registration number: CRD42013006880. Biofeedback is not new

  5. Investigating the impact of audio instruction and audio-visual biofeedback for lung cancer radiation therapy

    Science.gov (United States)

    George, Rohini

    Lung cancer accounts for 13% of all cancers in the Unites States and is the leading cause of deaths among both men and women. The five-year survival for lung cancer patients is approximately 15%.(ACS facts & figures) Respiratory motion decreases accuracy of thoracic radiotherapy during imaging and delivery. To account for respiration, generally margins are added during radiation treatment planning, which may cause a substantial dose delivery to normal tissues and increase the normal tissue toxicity. To alleviate the above-mentioned effects of respiratory motion, several motion management techniques are available which can reduce the doses to normal tissues, thereby reducing treatment toxicity and allowing dose escalation to the tumor. This may increase the survival probability of patients who have lung cancer and are receiving radiation therapy. However the accuracy of these motion management techniques are inhibited by respiration irregularity. The rationale of this thesis was to study the improvement in regularity of respiratory motion by breathing coaching for lung cancer patients using audio instructions and audio-visual biofeedback. A total of 331 patient respiratory motion traces, each four minutes in length, were collected from 24 lung cancer patients enrolled in an IRB-approved breathing-training protocol. It was determined that audio-visual biofeedback significantly improved the regularity of respiratory motion compared to free breathing and audio instruction, thus improving the accuracy of respiratory gated radiotherapy. It was also observed that duty cycles below 30% showed insignificant reduction in residual motion while above 50% there was a sharp increase in residual motion. The reproducibility of exhale based gating was higher than that of inhale base gating. Modeling the respiratory cycles it was found that cosine and cosine 4 models had the best correlation with individual respiratory cycles. The overall respiratory motion probability distribution

  6. Beta relaxation of nonpolymeric liquids close to the glass transition

    DEFF Research Database (Denmark)

    Olsen, Niels Boye; Christensen, Tage Emil; Dyre, Jeppe

    2000-01-01

    Dielectric beta relaxation in a pyridine-toluene solution is studied close to the glass transition. Loss peak frequency and maximum loss both exhibit thermal hysteresis. An annealing-state-independent parameter involving loss and loss peak frequency is identified. This parameter has a simple...

  7. Hastelloy X fuel element creep relaxation and residual effects

    International Nuclear Information System (INIS)

    Castle, R.A.

    1971-01-01

    A worst case, seven element, asymmetric fuel, thermal environment was assumed and a creep relaxation analysis generated. The fuel element clad is .020 inch Hastelloy X. The contact load decreased from 11.6 pounds to 5.87 pounds in 100,000 hours. The residual stresses were then computed for various shutdown times. (U.S.)

  8. Biofeedback as a first-line treatment for overactive bladder syndrome refractory to standard urotherapy in children.

    Science.gov (United States)

    Ebiloglu, Turgay; Kaya, Engin; Köprü, Burak; Topuz, Bahadır; Irkilata, Hasan Cem; Kibar, Yusuf

    2016-10-01

    Overactive bladder syndrome (OAB) and dysfunctional voiding (DV) are subgroups of lower urinary tract dysfunction (LUTD). Standard urotherapy is the first-line treatment option of OAB in children. The aim was to investigate the use of biofeedback as a first-line treatment option in OAB refractory to standard urotherapy, and determine the factors affecting efficacy. Between 2005 and 2015, we retrospectively analyzed a total of 136 hospital records of children with OAB who had not previously used any anticholinergics and were refractory to standard urotherapy. Patients with urgency and/or urge incontinence and/or making holding maneuvers to suppress urgency were defined as having OAB symptoms, and resolution of these complaints was defined as successful biofeedback therapy. Seventy-three of 136 OAB patients' urgency recovered by biofeedback therapy with the success rate of 53% (p biofeedback therapies, respectively (p Biofeedback can be thought of as the first-line treatment option when standard urotherapy fails in children with OAB. Copyright © 2016 Journal of Pediatric Urology Company. Published by Elsevier Ltd. All rights reserved.

  9. A Vibrotactile and Plantar Force Measurement-Based Biofeedback System: Paving the Way towards Wearable Balance-Improving Devices

    Directory of Open Access Journals (Sweden)

    Christina Zong-Hao Ma

    2015-12-01

    Full Text Available Although biofeedback systems have been used to improve balance with success, they were confined to hospital training applications. Little attempt has been made to investigate the use of in-shoe plantar force measurement and wireless technology to turn hospital training biofeedback systems into wearable devices. This research developed a wearable biofeedback system which detects body sway by analyzing the plantar force and provides users with the corresponding haptic cues. The effects of this system were evaluated in thirty young and elderly subjects with simulated reduced foot sensation. Subjects performed a Romberg test under three conditions: (1 no socks, system turned-off; (2 wearing five layers of socks, system turned-off; (3 wearing five layers of socks, and system turned-on. Degree of body sway was investigated by computing the center of pressure (COP movement measured by a floor-mounted force platform. Plantar tactile sensation was evaluated using a monofilament test. Wearing multiple socks significantly decreased the plantar tactile sensory input (p < 0.05, and increased the COP parameters (p < 0.017, indicating increased postural sway. After turning on the biofeedback system, the COP parameters decreased significantly (p < 0.017. The positive results of this study should inspire future development of wearable plantar force-based biofeedback systems for improving balance in people with sensory deficits.

  10. A Vibrotactile and Plantar Force Measurement-Based Biofeedback System: Paving the Way towards Wearable Balance-Improving Devices.

    Science.gov (United States)

    Ma, Christina Zong-Hao; Wan, Anson Hong-Ping; Wong, Duo Wai-Chi; Zheng, Yong-Ping; Lee, Winson Chiu-Chun

    2015-12-15

    Although biofeedback systems have been used to improve balance with success, they were confined to hospital training applications. Little attempt has been made to investigate the use of in-shoe plantar force measurement and wireless technology to turn hospital training biofeedback systems into wearable devices. This research developed a wearable biofeedback system which detects body sway by analyzing the plantar force and provides users with the corresponding haptic cues. The effects of this system were evaluated in thirty young and elderly subjects with simulated reduced foot sensation. Subjects performed a Romberg test under three conditions: (1) no socks, system turned-off; (2) wearing five layers of socks, system turned-off; (3) wearing five layers of socks, and system turned-on. Degree of body sway was investigated by computing the center of pressure (COP) movement measured by a floor-mounted force platform. Plantar tactile sensation was evaluated using a monofilament test. Wearing multiple socks significantly decreased the plantar tactile sensory input (p biofeedback system, the COP parameters decreased significantly (p biofeedback systems for improving balance in people with sensory deficits.

  11. Relaxation of Shot-Peened Residual Stresses Under Creep Loading (Preprint)

    Science.gov (United States)

    2008-10-01

    Residual Stresses,” SAE Technical Paper No. 710285, SAE , 1971. [8] Hoffman, J., Scholtes, B., Vöhringer, O., and Macherauch, E., “Thermal relaxation of...relaxation in an AISI 4140 steel due to quasistatic and cyclic loading at higher temperatures,” Material Science and Engineering A248, 1998, pp. 9

  12. Relaxation of residual stress in MMC after combined plastic deformation and heat treatment

    International Nuclear Information System (INIS)

    Bruno, G.; Ceretti, M.; Girardin, E.; Giuliani, A.; Manescu, A.

    2004-01-01

    Neutron Diffraction shows that plastic pre-deformation and heat treatments have opposite effects on the residual stress in Al-SiC p composites. The thermal micro residual stress is relaxed or even reversed by pre-strains above 0.2%, but restored by heat treatments. The sense of relaxation changes above 400 deg. C (the mixing temperature)

  13. Pilot Randomized Trial Comparing Intersession Scheduling of Biofeedback Results to Individuals with Chronic Pain: Influence on Psychologic Function and Pain Intensity.

    Science.gov (United States)

    Weeks, Douglas L; Whitney, Anthony A; Tindall, Angelique G; Carter, Gregory T

    2015-10-01

    The objective of this study was to compare the effectiveness of two biofeedback schedules on long-term improvement in physical and psychologic reactivity to chronic nonmalignant pain. This study is a prospective, randomized pilot trial. Twenty adults with chronic pain engaged in heart rate variability (HRV) biofeedback training for nine sessions with HRV presented visually. Two groups, formed by random assignment, were compared: The faded feedback group received concurrent visual HRV biofeedback in session 1, with the amount of biofeedback systematically reduced for ensuing sessions so that, by session 9, the participants were controlling HRV without external feedback. The full feedback group received visual HRV biofeedback continuously across all sessions. Outcome measures assessed at baseline, immediately after the program, and 3 mos after the program included pain intensity, fear-avoidance beliefs, and self-report physical functioning. Use of biofeedback skills was also assessed 3 mos after the program. Nominal variables were analyzed with χ. Continuous measures were analyzed with repeated-measures analyses of variance. The faded feedback schedule resulted in greater use of biofeedback skills at 3 mos and improved pain intensity and fear-avoidance beliefs after the program and at 3 mos. Physical functioning did not differ between groups. Systematically reducing the frequency of external visual feedback during HRV biofeedback training was associated with reduced reactivity to chronic pain. Results of this pilot study should be confirmed with a larger randomized study.

  14. The effects of whole body vibration combined biofeedback postural control training on the balance ability and gait ability in stroke patients.

    Science.gov (United States)

    Uhm, Yo-Han; Yang, Dae-Jung

    2017-11-01

    [Purpose] The purpose of this study was to examine the effect of biofeedback postural control training using whole body vibration in acute stroke patients on balance and gait ability. [Subjects and Methods] Thirty stroke patients participated in this study and were divided into a group of 10, a group for biofeedback postural control training combined with a whole body vibration, one for biofeedback postural control training combined with an aero-step, and one for biofeedback postural control training. Biorescue was used to measure the limits of stability, balance ability, and Lukotronic was used to measure step length, gait ability. [Results] In the comparison of balance ability and gait ability between the groups for before and after intervention, Group I showed a significant difference in balance ability and gait ability compared to Groups II and III. [Conclusion] This study showed that biofeedback postural control training using whole body vibration is effective for improving balance ability and gait ability in stroke patients.

  15. Effect of iodine impurity on relaxation of photoexcited silver chloride

    International Nuclear Information System (INIS)

    Vostrikova, Yu. V.; Klyuev, V. G.

    2008-01-01

    The time and temperature dependences of relaxation of excited AgCl and AgCl:I crystals is studied by the method of photostimulated flash of luminescence. The presence of iodine impurity in silver chloride gives rise to hole recombination (luminescence) centers and hole traps in the band gap. It is shown that the main contribution to the decrease in the concentration of electrons localized at deep traps is made by the recombination of electrons with holes released thermally from shallow localization levels (iodine-related centers). Estimation of activation energy for the relaxation process showed that these energies for the AgCl and AgCl:I samples under study are the same within the experimental error and are equal to E rel1 = 0.01 ± 0.0005 eV for the initial stage of relaxation and E rel2 = 0.09 ± 0.005 eV for the final state. This fact indicates that the majority of hole traps involved in the relaxation process in AgCl are related to iodine impurity. In the course of thermal relaxation in AgCl, relocalization of nonequilibrium charge carriers from shallow levels to deep levels is observed. The depth of the corresponding trap is E arl = 0.174 ± 0.03 eV.

  16. Relaxed states with plasma flow

    International Nuclear Information System (INIS)

    Avinash, K.; Taylor, J.B.

    1991-01-01

    In the theory of relaxation, a turbulent plasma reaches a state of minimum energy subject to constant magnetic helicity. In this state the plasma velocity is zero. Attempts have been made by introducing a number of different constraints, to obtain relaxed states with plasma flow. It is shown that these alternative constraints depend on two self-helicities, one for ions, and one for electrons. However, whereas there are strong arguments for the effective invariance of the original magnetic-helicity, these arguments do not apply to the self-helicities. Consequently the existence of relaxed states with flow remains in doubt. (author)

  17. A real time biofeedback using Kinect and Wii to improve gait for post-total knee replacement rehabilitation: a case study report.

    Science.gov (United States)

    Levinger, Pazit; Zeina, Daniel; Teshome, Assefa K; Skinner, Elizabeth; Begg, Rezaul; Abbott, John Haxby

    2016-01-01

    This study aimed to develop a low-cost real-time biofeedback system to assist with rehabilitation for patients following total knee replacement (TKR) and to assess its feasibility of use in a post-TKR patient case study design with a comparison group. The biofeedback system consisted of Microsoft Kinect(TM) and Nintendo Wii balance board with a dedicated software. A six-week inpatient rehabilitation program was augmented by biofeedback and tested in a single patient following TKR. Three patients underwent a six weeks standard rehabilitation with no biofeedback and served as a control group. Gait, function and pain were assessed and compared before and after the rehabilitation. The biofeedback software incorporated real time visual feedback to correct limb alignment, movement pattern and weight distribution. Improvements in pain, function and quality of life were observed in both groups. The strong improvement in the knee moment pattern demonstrated in the case study indicates feasibility of the biofeedback-augmented intervention. This novel biofeedback software has used simple commercially accessible equipment that can be feasibly incorporated to augment a post-TKR rehabilitation program. Our preliminary results indicate the potential of this biofeedback-assisted rehabilitation to improve knee function during gait. Research is required to test this hypothesis. Implications for Rehabilitation The real-time biofeedback system developed integrated custom-made software and simple low-cost commercially accessible equipment such as Kinect and Wii board to provide augmented information during rehabilitation following TKR. The software incorporated key rehabilitation principles and visual feedback to correct alignment of the lower legs, pelvic and trunk as well as providing feedback on limbs weight distribution. The case study patient demonstrated greater improvement in their knee function where a more normal biphasic knee moment was achieved following the six

  18. Effect of Electromyographic Biofeedback Training on Pain, Quadriceps Muscle Strength, and Functional Ability in Juvenile Rheumatoid Arthritis.

    Science.gov (United States)

    Eid, Mohamed Ahmed Mahmoud; Aly, Sobhy M; El-Shamy, Shamekh M

    2016-12-01

    To investigate the effects of electromyographic (EMG) biofeedback training on pain, quadriceps strength, and functional ability in juvenile rheumatoid arthritis (JRA). This is a randomized controlled study; 36 children (11 boys and 25 girls) with polyarticular JRA, with ages ranging from 8 to 13 years, were selected and assigned randomly, using computer-generated random numbers, into 2 groups. The control group (n = 18) received the conventional physical therapy program, whereas the study group (n = 18) received the same program as the control group in addition to EMG biofeedback-guided isometric exercises for 3 days a week for 12 weeks. Pain, peak torque of quadriceps strength, and functional ability were evaluated before, after 6 weeks, and at the end of 12 weeks of the treatment program. By 6 weeks, significant differences were observed in the study group (P biofeedback may be a useful intervention modality to reduce pain, improve quadriceps strength, and functional performance in JRA.

  19. Effect of gender on strength gains after isometric exercise coupled with electromyographic biofeedback in knee osteoarthritis: a preliminary study.

    Science.gov (United States)

    Anwer, S; Equebal, A; Nezamuddin, M; Kumar, R; Lenka, P K

    2013-09-01

    The objective of this trial was to evaluate the effect of gender on strength gains after five week training programme that consisted of isometric exercise coupled with electromyographic biofeedback to the quadriceps muscle. Forty-three (20 men and 23 women) patients with knee osteoarthritis (OA), were placed into two groups based on their gender. Both groups performed isometric exercise coupled with electromyographic biofeedback for five days a week for five weeks. Both groups reported gains in muscle strength after five week training. However, the difference was found to be statistically insignificant between the two groups (P=0.224). The results suggest that gender did not affect gains in muscle strength by isometric exercise coupled with electromyographic biofeedback in patients with knee OA. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

  20. Real-time visual biofeedback during weight bearing improves therapy compliance in patients following lower extremity fractures.

    Science.gov (United States)

    Raaben, Marco; Holtslag, Herman R; Leenen, Luke P H; Augustine, Robin; Blokhuis, Taco J

    2018-01-01

    Individuals with lower extremity fractures are often instructed on how much weight to bear on the affected extremity. Previous studies have shown limited therapy compliance in weight bearing during rehabilitation. In this study we investigated the effect of real-time visual biofeedback on weight bearing in individuals with lower extremity fractures in two conditions: full weight bearing and touch-down weight bearing. 11 participants with full weight bearing and 12 participants with touch-down weight bearing after lower extremity fractures have been measured with an ambulatory biofeedback system. The participants first walked 15m and the biofeedback system was only used to register the weight bearing. The same protocol was then repeated with real-time visual feedback during weight bearing. The participants could thereby adapt their loading to the desired level and improve therapy compliance. In participants with full weight bearing, real-time visual biofeedback resulted in a significant increase in loading from 50.9±7.51% bodyweight (BW) without feedback to 63.2±6.74%BW with feedback (P=0.0016). In participants with touch-down weight bearing, the exerted lower extremity load decreased from 16.7±9.77kg without feedback to 10.27±4.56kg with feedback (P=0.0718). More important, the variance between individual steps significantly decreased after feedback (P=0.018). Ambulatory monitoring weight bearing after lower extremity fractures showed that therapy compliance is low, both in full and touch-down weight bearing. Real-time visual biofeedback resulted in significantly higher peak loads in full weight bearing and increased accuracy of individual steps in touch-down weight bearing. Real-time visual biofeedback therefore results in improved therapy compliance after lower extremity fractures. Copyright © 2017 Elsevier B.V. All rights reserved.

  1. Heart rate biofeedback fails to enhance children's ability to identify time spent in moderate to vigorous physical activity.

    Science.gov (United States)

    Conley, Marguerite M; Gastin, Paul B; Brown, Helen; Shaw, Christine

    2011-03-01

    Physical activity recommendations for children in several countries advise that all young people should accumulate at least 60 min of moderate to vigorous physical activity every day. Perceiving physical activity intensity, however, can be a difficult task for children and it is not clear whether children can identify their levels of moderate to vigorous physical activity in accordance with the recommended guidelines. This study aimed to (1) explore whether children can identify time spent in moderate to vigorous physical activity; and (2) investigate whether heart rate biofeedback would improve children's ability to estimate time spent in moderate to vigorous physical activity. Thirty seven children (15 boys and 22 girls, mean age 12.6 years) wore data recording Polar E600 heart rate monitors during eight physical education lessons. At the end of each lesson children's estimated time in zone was compared to their actual time in zone. During a six lesson Intervention phase, one class was assigned to a biofeedback group whilst the other class acted as the control group and received no heart rate biofeedback. Post-Intervention, students in the biofeedback group were no better than the control group at estimating time spent in zone (mean relative error of estimation biofeedback group: Pre-Intervention 41±32% to Post-Intervention 28±26%; control group: Pre-Intervention 40±39% to Post-Intervention 31±37%). Thus it seems that identifying time spent in moderate to vigorous physical activity remains a complex task for children aged 11-13 even with the help of heart rate biofeedback. Copyright © 2010 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

  2. Efficacy of Biofeedback Therapy before and after Sphincteroplasty for Fecal Incontinence because of Obstetric Injury: A Randomized Controlled Trial

    Directory of Open Access Journals (Sweden)

    Leila Ghahramani

    2016-03-01

    Full Text Available Fecal incontinence is a challenging condition in that it exerts various psychosocial impacts on daily life. Different treatment modalities have been suggested for fecal incontinence. The present study aimed to evaluate the efficacy of biofeedback therapy in combination with surgery in the management of fecal incontinence. The present randomized controlled trial was performed on 27 women with a complaint of fecal incontinence because of delivery trauma. The patients underwent sphincteroplasty and levatorplasty via the same method by 2 colorectal surgeons. In Group I, biofeedback therapy was performed 3 months before and 6 months after the surgery; in Group II, biofeedback therapy was applied only 6 months after the surgery; and in Group III, only surgical management was performed. The results revealed a significant difference between the preoperative and postoperative Wexner scores of incontinence in all the 3 groups. Additionally, the difference between the preoperative and postoperative scores was significant only in Group I and Group III, but not in Group II. The reduction in the Wexner score was significantly less in Group III. However, no significant difference was observed between the 3 groups concerning the mean difference of preoperative and postoperative manometry. The present study revealed no significant role for biofeedback therapy alone in the improvement of manometric evaluation. However, the Wexner score, which is an indicator of patient satisfaction, increased with biofeedback therapy following sphincteroplasty. In general, surgical treatment is now reserved for selected patients with fecal incontinence and has recently been developed with biofeedback therapy. Trial Registration Number: IRCT201206039936N1

  3. Biofeedback for nonneuropathic daytime voiding disorders in children: a systematic review and meta-analysis of randomized controlled trials.

    Science.gov (United States)

    Fazeli, Mir Sohail; Lin, Yiqun; Nikoo, Nooshin; Jaggumantri, Sravan; Collet, Jean-Paul; Afshar, Kourosh

    2015-01-01

    Biofeedback has been used to treat children with symptoms of bladder dysfunction not responding to standard therapy alone. However, evidence of the effectiveness of biofeedback is scarce and is based on small studies. We conducted a systematic review of the literature to assess the effects of biofeedback as adjunctive therapy for symptoms of nonneuropathic voiding disorders in children up to age 18 years. We searched MEDLINE(®), Embase(®) and CENTRAL on the OvidSP(®) platform as well as conference proceedings for randomized trials presented at scientific conventions, symposia and workshops through August 13, 2013. Hand searches and review of reference lists of retrieved articles were also performed. Five eligible studies were included in the systematic review, of which 4 (382 participants) were pooled in the meta-analysis based on available outcomes data. The overall proportion of cases with resolved incontinence at month 6 was similar in the biofeedback and control groups (OR 1.37 [95% CI 0.64 to 2.93], RD 0.07 [-0.09, 0.23]). There was also no significant difference in mean maximum urinary flow rate (mean difference 0.50 ml, range -0.56 to 1.55) or likelihood of urinary tract infection (OR 1.30 [95% CI 0.65 to 2.58]). Current evidence does not support the effectiveness of biofeedback in the management of children with nonneuropathic voiding disorders. More high quality, randomized controlled trials are needed to better evaluate the effect of biofeedback. Copyright © 2015 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

  4. Slowing hot-carrier relaxation in graphene using a magnetic field

    Science.gov (United States)

    Plochocka, P.; Kossacki, P.; Golnik, A.; Kazimierczuk, T.; Berger, C.; de Heer, W. A.; Potemski, M.

    2009-12-01

    A degenerate pump-probe technique is used to investigate the nonequilibrium carrier dynamics in multilayer graphene. Two distinctly different dynamics of the carrier relaxation are observed. A fast relaxation (˜50fs) of the carriers after the initial effect of phase-space filling followed by a slower relaxation (˜4ps) due to thermalization. Both relaxation processes are less efficient when a magnetic field is applied at low temperatures which is attributed to the suppression of the electron-electron Auger scattering due to the nonequidistant Landau-level spacing of the Dirac fermions in graphene.

  5. Effectiveness of treatment using fecal incontinence biofeedback isolated or associated with electrical stimulation

    Directory of Open Access Journals (Sweden)

    Suelen Melão

    2014-10-01

    Full Text Available Introduction: The prevalence of fecal incontinence (FI has increased in recent decades, due to an aging population; and result in negative impacts on quality of life. Therefore, it is essential to search for an effective treatment in order to minimize the morbidity caused by incontinence. Objective: To evaluate the effect of perineal training in the treatment of patients with fecal incontinence by biofeedback. Method: This is a prospective study which evaluated 85 patients with FI from January 2009 to January 2014, at the Coloproctology outpatient clinic of the Hospital São Lucas/Cascavel, Paraná. Results: Mean age was 47 years and the duration of treatment ranged from 5 to 25 sessions (mean, 13 sessions. From the women involved in the study, 70% (50 had vaginal deliveries and 34 (40% participants were submitted to some orificial surgery. The FI score at baseline was 10.79 (6–17 and post-treatment FI was 2 (0–14 (p < 0.001. In the population studied, 49.4% (42 of the patients had an associated pre-BFT UI; and only 8.2% (7 had post-BFT UI (p < 0.001. Conclusions: The data presented in this study confirm that perineal training through biofeedback was effective in the treatment of patients with fecal incontinence without immediate indication for surgery, still ensuring for this technique the advantages of being effective, painless and of low cost. Resumo: Introdução: A prevalência de incontinência fecal (IF vem aumentando nas últimas décadas devido ao envelhecimento da população; e resulta em impactos negativos na qualidade de vida. Logo, torna-se fundamental a busca de um tratamento efetivo, a fim de minimizar a morbidade ocasionada pela incontinência. Objetivo: Avaliar o efeito do treinamento perineal no tratamento de pacientes portadores de incontinência fecal através do biofeedback. Método: Estudo prospectivo, que avaliou 85 pacientes com IF no período de janeiro de 2009 a janeiro de 2014, no ambulatório de

  6. Analysis and Modeling of the Galvanic Skin Response Spontaneous Component in the context of Intelligent Biofeedback Systems Development

    Science.gov (United States)

    Unakafov, A.

    2009-01-01

    The paper presents an approach to galvanic skin response (GSR) spontaneous component analysis and modeling. In the study a classification of biofeedback training methods is given, importance of intelligent methods development is shown. The INTENS method, which is perspective for intellectualization, is presented. An important problem of biofeedback training method intellectualization - estimation of the GSR spontaneous component - is solved in the main part of the work. Its main characteristics are described; results of GSR spontaneous component modeling are shown. Results of small research of an optimum material for GSR probes are presented.

  7. Relaxed states of tokamak plasmas

    International Nuclear Information System (INIS)

    Kucinski, M.Y.; Okano, V.

    1993-01-01

    The relaxed states of tokamak plasmas are studied. It is assumed that the plasma relaxes to a quasi-steady state which is characterized by a minimum entropy production rate, compatible with a number of prescribed conditions and pressure balance. A poloidal current arises naturally due to the anisotropic resistivity. The minimum entropy production theory is applied, assuming the pressure equilibrium as fundamental constraint on the final state. (L.C.J.A.)

  8. Negative magnetic relaxation in superconductors

    Directory of Open Access Journals (Sweden)

    Krasnoperov E.P.

    2013-01-01

    Full Text Available It was observed that the trapped magnetic moment of HTS tablets or annuli increases in time (negative relaxation if they are not completely magnetized by a pulsed magnetic field. It is shown, in the framework of the Bean critical-state model, that the radial temperature gradient appearing in tablets or annuli during a pulsed field magnetization can explain the negative magnetic relaxation in the superconductor.

  9. Relaxation effects in ferrous complexes

    International Nuclear Information System (INIS)

    Nicolini, C.; Mathieu, J.P.; Chappert, J.

    1976-01-01

    The slow relaxation mechanism of the Fe 2+ ion in the tri-fluorinated TF(acac) and hexafluorinated HF(acac) complexes of Fe(II) acetylacetonate was investigated. The 300K and 77K Moessbauer spectra for TF(acac) consist in a slightly asymmetric quadrupole doublet. On the contrary, at 4.2K the higher energy line is strongly widened; that is typical of a slowing down in the electron relaxation frequency [fr

  10. Efficacy of biofeedback therapy on sleep bruxism: A systematic review and meta-analysis.

    Science.gov (United States)

    Jokubauskas, L; Baltrušaitytė, A

    2018-03-26

    This study updates the review published by Wang et al in 2014 (Sleep Breath 2014;18(2):235-242). The review focuses on the most recent literature on management of sleep bruxism (SB) with biofeedback. An electronic search was conducted in five databases searching for articles published later than the date of Wang et al's search, viz., October 2012. Six articles of 2320 identified citations involving 86 adult participants were included in the qualitative synthesis. Of them, 4 were randomised controlled trials (RCTs) and 2 were uncontrolled before-after studies. Different feedback modalities (electrical, auditory and vibratory stimulus) were investigated. The overall quality of the selected studies was assessed using the GRADE criteria. Due to heterogeneity between studies, the quantitative synthesis was performed out of three RCTs, of which two were retrieved from the previous review. The meta-analysis indicated a non-significant difference in electromyographic-measured SB episodes per hour after one night of contingent electrical stimulation (CES) compared with placebo control, yet a significant difference was shown after five nights of CES. The quality of evidence identified through GRADEpro was from low to moderate, due to imprecision and inconsistency between studies. Qualitative synthesis did not present a reliable reduction in clinical pain levels; however, no substantial sleep disturbances were indicated following the intervention. In conclusion, one of the biofeedback modalities, CES, is effective in reducing SB-related motor activities after a short-term treatment period. However, evidence of long-term effects is lacking. Further longitudinal studies with larger samples are necessary to acknowledge the clinical application of biofeedback. © 2018 John Wiley & Sons Ltd.

  11. The effect of autogenic training and biofeedback on motion sickness tolerance.

    Science.gov (United States)

    Jozsvai, E E; Pigeau, R A

    1996-10-01

    Motion sickness is characterized by symptoms of vomiting, drowsiness, fatigue and idiosyncratic changes in autonomic nervous system (ANS) responses such as heart rate (HR) and skin temperature (ST). Previous studies found that symptoms of motion sickness are controllable through self-regulation of ANS responses and the best method to teach such control is autogenic-feedback (biofeedback) training. Recent experiments indicated that biofeedback training is ineffective in reducing symptoms of motion sickness or in increasing tolerance to motion. If biofeedback facilitates learning of ANS self-regulation then autogenic training with true feedback (TFB) should lead to better control over ANS responses and better motion tolerance than autogenic training with false feedback (FFB). If there is a relationship between ANS self-regulation and coping with motion stress, a significant correlation should be found between amounts of control over ANS responses and measures of motion tolerance and/or symptoms of motion sickness. There were 3 groups of 6 subjects exposed for 6 weeks to weekly sessions of Coriolis stimulation to induce motion sickness. Between the first and second Coriolis sessions, subjects in the experimental groups received five episodes of autogenic training with either true (group TFB) or false (group FFB) feedback on their HR and ST. The control group (CTL) received no treatment. Subjects learned to control their HR and ST independent of whether they received true or false feedback. Learned control of ST and HR was not related to severity of motion sickness or subject's ability to withstand Coriolis stimulation following treatment. A lack of significant correlation between these variables suggested that subjects were not able to apply their skills of ANS self-regulation in the motion environment, and/ or such skills had little value in reducing symptoms of motion sickness or enhancing their ability to withstand rotations.

  12. Audio-Biofeedback training for posture and balance in Patients with Parkinson's disease

    Directory of Open Access Journals (Sweden)

    Zijlstra Wiebren

    2011-06-01

    Full Text Available Abstract Background Patients with Parkinson's disease (PD suffer from dysrhythmic and disturbed gait, impaired balance, and decreased postural responses. These alterations lead to falls, especially as the disease progresses. Based on the observation that postural control improved in patients with vestibular dysfunction after audio-biofeedback training, we tested the feasibility and effects of this training modality in patients with PD. Methods Seven patients with PD were included in a pilot study comprised of a six weeks intervention program. The training was individualized to each patient's needs and was delivered using an audio-biofeedback (ABF system with headphones. The training was focused on improving posture, sit-to-stand abilities, and dynamic balance in various positions. Non-parametric statistics were used to evaluate training effects. Results The ABF system was well accepted by all participants with no adverse events reported. Patients declared high satisfaction with the training. A significant improvement of balance, as assessed by the Berg Balance Scale, was observed (improvement of 3% p = 0.032, and a trend in the Timed up and go test (improvement of 11%; p = 0.07 was also seen. In addition, the training appeared to have a positive influence on psychosocial aspects of the disease as assessed by the Parkinson's disease quality of life questionnaire (PDQ-39 and the level of depression as assessed by the Geriatric Depression Scale. Conclusions This is, to our knowledge, the first report demonstrating that audio-biofeedback training for patients with PD is feasible and is associated with improvements of balance and several psychosocial aspects.

  13. Neural activity based biofeedback therapy for Autism spectrum disorder through wearable wireless textile EEG monitoring system

    Science.gov (United States)

    Sahi, Ahna; Rai, Pratyush; Oh, Sechang; Ramasamy, Mouli; Harbaugh, Robert E.; Varadan, Vijay K.

    2014-04-01

    Mu waves, also known as mu rhythms, comb or wicket rhythms are synchronized patterns of electrical activity involving large numbers of neurons, in the part of the brain that controls voluntary functions. Controlling, manipulating, or gaining greater awareness of these functions can be done through the process of Biofeedback. Biofeedback is a process that enables an individual to learn how to change voluntary movements for purposes of improving health and performance through the means of instruments such as EEG which rapidly and accurately 'feedback' information to the user. Biofeedback is used for therapeutic purpose for Autism Spectrum Disorder (ASD) by focusing on Mu waves for detecting anomalies in brain wave patterns of mirror neurons. Conventional EEG measurement systems use gel based gold cup electrodes, attached to the scalp with adhesive. It is obtrusive and wires sticking out of the electrodes to signal acquisition system make them impractical for use in sensitive subjects like infants and children with ASD. To remedy this, sensors can be incorporated with skull cap and baseball cap that are commonly used for infants and children. Feasibility of Textile based Sensor system has been investigated here. Textile based multi-electrode EEG, EOG and EMG monitoring system with embedded electronics for data acquisition and wireless transmission has been seamlessly integrated into fabric of these items for continuous detection of Mu waves. Textile electrodes were placed on positions C3, CZ, C4 according to 10-20 international system and their capability to detect Mu waves was tested. The system is ergonomic and can potentially be used for early diagnosis in infants and planning therapy for ASD patients.

  14. Effects of Biofeedback in Preventing Urinary Incontinence and Erectile Dysfunction after Radical Prostatectomy

    Directory of Open Access Journals (Sweden)

    Fabiana S. B. Perez

    2018-02-01

    Full Text Available In this study, we present a biofeedback method for the strengthening of perineal muscles during the preoperative procedures for radical prostatectomy, and we evaluate this technique as a prevention measure against complications such as urinary incontinence (UI and erectile dysfunction (ED, which affect prostatectomy patients after surgery. In the experimental protocol, the patients performed specific exercises with the help of a device that provided the patient with visual biofeedback, based on a plot of the anal pressure. For the experimental protocol, we selected 20 male patients, with an average age of 64.0 years, and submitted them to ten therapeutic sessions each. A control group consisting of 32 men with an average age of 66.3 years, who were treated with the same surgical procedure but not with the preoperative procedures, also took part in the experiment. To evaluate UI and ED after the surgery in both control and experimental groups, we used two validated questionnaires—to assess UI, we used the King’s Health Questionnaire (KHQ and, for ED, we used the International Index of Erectile Function (IIEF-5 Questionnaire. We compared the variables associated with UI and ED after the surgery for the control and experimental groups. The occurrence of UI after radical prostatectomy in the control group (100% of the patients was higher than that for the experimental group (5% of the patients, with p < 0.0001. Likewise, the occurrence of erectile dysfunction after prostatectomy in the control group (48.6% of the patients was higher than that for the experimental group (5% of the patients, with p < 0.0001. The number of nocturia events also decreased as a consequence of the intervention (p < 0.0001, as did the number of disposable underwear units for urinary incontinence (p < 0.0001. Furthermore, we compared, only for the experimental group, the anal pressure before the biofeedback intervention and after the surgery, and we

  15. Evaluating the ChillFish Biofeedback Game with Children with ADHD

    DEFF Research Database (Denmark)

    Sonne, Tobias; Jensen, Mads Møller

    2016-01-01

    Breathing exercises have been shown to have multiple benefits for children with Attention Deficit Hyperactivity Disorder (ADHD). However, these children can have issues retaining attention to such an exercise. In this paper we present a study of ChillFish, a respiration game for children with ADHD....... Our findings show tendencies that the game works in terms of having a calming effect. However, the study also highlighted issues of evaluating biofeedback games with children with ADHD that are not present when evaluating with adults. This work presents an iteration in the ChillFish development cycle...

  16. Biofeedback Cardiovascular e suas Aplicações: revisão de literatura

    OpenAIRE

    Gomes, July Silveira; Coghi, Marcos Fábio; Coghi, Priscila

    2014-01-01

    El biofeedback cardiovascular es una técnica de automodulación fisiológica mediada por la resonancia entre dos mecanismos de regulación cardiovascular: el reflejo barorreceptor y la arritmia sinusal respiratoria. Cuando ese fenómeno ocurre, es posible visualizar un aumento significativo en la amplitud de la frecuencia en torno a 0.1Hz, llamada baja frecuencia (low frequency, LF). En ese trabajo, se consultó la base de datos Pubmed y fueron revisados 31 trabajos, publicados entre el 2000 y jun...

  17. Stress relaxation analysis and irradiation creep and swelling in pressure tubes

    International Nuclear Information System (INIS)

    Beeston, J.M.; Burr, T.K.

    1979-01-01

    An analysis is presented of slit width test information on two pressure tubes that had been irradiated in test reactors. The analysis showed that differential swelling stresses and thermal stresses undergo relaxation. The mechanism responsible for the stress relaxation at temperatures less than 700 K was irradiation creep. Irradiation creep in thermal test reactor pressure tubes is evidently greater than it would be at equivalent conditions in fast reactors. The residual stresses observed in the slit width tests varied between 30 and 257 MPa and would act to reduce the operating stresses, thus allowing for increased service life of the tubes as compared with no stress relaxation

  18. Relaxed impact craters on Ganymede: Regional variation and high heat flows

    Science.gov (United States)

    Singer, Kelsi N.; Bland, Michael T.; Schenk, Paul M.; McKinnon, William B.

    2018-01-01

    Viscously relaxed craters provide a window into the thermal history of Ganymede, a satellite with copious geologic signs of past high heat flows. Here we present measurements of relaxed craters in four regions for which suitable imaging exists: near Anshar Sulcus, Tiamat Sulcus, northern Marius Regio, and Ganymede's south pole. We describe a technique to measure apparent depth, or depth of the crater with respect to the surrounding terrain elevation. Measured relaxation states are compared with results from finite element modeling to constrain heat flow scenarios [see companion paper: Bland et al. (2017)]. The presence of numerous, substantially relaxed craters indicates high heat flows—in excess of 30–40 mW m−2 over 2 Gyr, with many small (heat flows. Crater relaxation states are bimodal for some equatorial regions but not in the region studied near the south pole, which suggests regional variations in Ganymede's thermal history.

  19. Relaxed impact craters on Ganymede: Regional variation and high heat flows

    Science.gov (United States)

    Singer, Kelsi N.; Bland, Michael T.; Schenk, Paul M.; McKinnon, William B.

    2018-05-01

    Viscously relaxed craters provide a window into the thermal history of Ganymede, a satellite with copious geologic signs of past high heat flows. Here we present measurements of relaxed craters in four regions for which suitable imaging exists: near Anshar Sulcus, Tiamat Sulcus, northern Marius Regio, and Ganymede's south pole. We describe a technique to measure apparent depth, or depth of the crater with respect to the surrounding terrain elevation. Measured relaxation states are compared with results from finite element modeling to constrain heat flow scenarios [see companion paper: Bland et al. (2017)]. The presence of numerous, substantially relaxed craters indicates high heat flows-in excess of 30-40 mW m-2 over 2 Gyr, with many small (heat flows. Crater relaxation states are bimodal for some equatorial regions but not in the region studied near the south pole, which suggests regional variations in Ganymede's thermal history.

  20. Optimization of material composition of nonhomogeneous plate for thermal stress relaxation making use of neural network. Analysis taking into account the relative heat transfer at boundary surfaces when subjected to unsteady heat supply

    International Nuclear Information System (INIS)

    Ootao, Yoshihiro; Kawamura, Ryuusuke; Tanigawa, Yoshinobu; Imamura, Ryuutarou

    1998-01-01

    In this study, a neural network is applied to optimization problems of material compositions for a nonhomogeneous plate with arbitrarily distributed and continuously varied material properties such as Functionally Graded Material. Unsteady temperature distribution for such nonhomogeneous plate is evaluated by taking into account the bounds of the number of the layers. Furthermore, the thermal stress components for an infinitely long nonhomogeneous plate are formulated under the mechanical condition of being traction free. As a numerical example, the plate composed of zirconium oxide and titanium alloy is considered. And, as the optimization problem of minimizing the thermal stress distribution, the numerical calculations are carried out making use of neural network, and the optimum material composition is determined taking into account the effect of temperature-dependency of material properties. Furthermore, the results obtained by neural network and ordinary nonlinear programming method are compared. (author)

  1. Influence of visual and auditory biofeedback on partial body weight support treadmill training of individuals with chronic hemiparesis: a randomized controlled clinical trial.

    Science.gov (United States)

    Brasileiro, A; Gama, G; Trigueiro, L; Ribeiro, T; Silva, E; Galvão, É; Lindquist, A

    2015-02-01

    Stroke is an important causal factor of deficiency and functional dependence worldwide. To determine the immediate effects of visual and auditory biofeedback, combined with partial body weight supported (PBWS) treadmill training on the gait of individuals with chronic hemiparesis. Randomized controlled trial. Outpatient rehabilitation hospital. Thirty subjects with chronic hemiparesis and ability to walk with some help. Participants were randomized to a control group that underwent only PBWS treadmill training; or experimental I group with visual biofeedback from the display monitor, in the form of symbolic feet as the subject took a step; or experimental group II with auditory biofeedback associated display, using a metronome at 115% of the individual's preferred cadence. They trained for 20 minutes and were evaluated before and after training. Spatio-temporal and angular gait variables were obtained by kinematics from the Qualisys Motion Analysis system. Increases in speed and stride length were observed for all groups over time (speed: F=25.63; Phemiparesis, in short term. Additional studies are needed to determine whether, in long term, the biofeedback will promote additional benefit to the PBWS treadmill training. The findings of this study indicate that visual and auditory biofeedback does not bring immediate benefits on PBWS treadmill training of individuals with chronic hemiparesis. This suggest that, for additional benefits are achieved with biofeedback, effects should be investigated after long-term training, which may determine if some kind of biofeedback is superior to another to improve the hemiparetic gait.

  2. Stability and suppression of turbulence in relaxing molecular gas flows

    CERN Document Server

    Grigoryev, Yurii N

    2017-01-01

    This book presents an in-depth systematic investigation of a dissipative effect which manifests itself as the growth of hydrodynamic stability and suppression of turbulence in relaxing molecular gas flows. The work describes the theoretical foundations of a new way to control stability and laminar turbulent transitions in aerodynamic flows. It develops hydrodynamic models for describing thermal nonequilibrium gas flows which allow the consideration of suppression of inviscid acoustic waves in 2D shear flows. Then, nonlinear evolution of large-scale vortices and Kelvin-Helmholtz waves in relaxing shear flows are studied. Critical Reynolds numbers in supersonic Couette flows are calculated analytically and numerically within the framework of both linear and nonlinear classical energy hydrodynamic stability theories. The calculations clearly show that the relaxation process can appreciably delay the laminar-turbulent transition. The aim of the book is to show the new dissipative effect, which can be used for flo...

  3. Hydrodynamic relaxations in dissipative particle dynamics

    Science.gov (United States)

    Hansen, J. S.; Greenfield, Michael L.; Dyre, Jeppe C.

    2018-01-01

    This paper studies the dynamics of relaxation phenomena in the standard dissipative particle dynamics (DPD) model [R. D. Groot and P. B. Warren, J. Chem. Phys. 107, 4423 (1997)]. Using fluctuating hydrodynamics as the framework of the investigation, we focus on the collective transverse and longitudinal dynamics. It is shown that classical hydrodynamic theory predicts the transverse dynamics at relatively low temperatures very well when compared to simulation data; however, the theory predictions are, on the same length scale, less accurate for higher temperatures. The agreement with hydrodynamics depends on the definition of the viscosity, and here we find that the transverse dynamics are independent of the dissipative and random shear force contributions to the stress. For high temperatures, the spectrum for the longitudinal dynamics is dominated by the Brillouin peak for large length scales and the relaxation is therefore governed by sound wave propagation and is athermal. This contrasts the results at lower temperatures and small length scale, where the thermal process is clearly present in the spectra. The DPD model, at least qualitatively, re-captures the underlying hydrodynamical mechanisms, and quantitative agreement is excellent at intermediate temperatures for the transverse dynamics.

  4. Efficacy of Biofeedback Therapy in the Treatment of Dyssynergic Defecation in Community-Dwelling Elderly Women.

    Science.gov (United States)

    Simón, Miguel A; Bueno, Ana M

    The aim of this study was to evaluate the efficacy of biofeedback therapy in the treatment of dyssynergic defecation in chronically constipated community-dwelling elderly women. After an initial assessment phase carried out during 1 month, 20 chronically constipated women with dyssynergic defecation were randomly assigned to either electromyographic biofeedback (EMG-BF) group (n=10) or control group (n=10). Outcome measures used to evaluate the efficacy of treatment were weekly stool frequency, sensation of incomplete evacuation, difficulty evacuation level, mean EMG-activity (μV) of the external anal sphincter during straining to defecate and Anismus index. The results obtained in this randomized controlled trial showed significant differences between the groups in all the dependent variables after 1 month of treatment. Moreover, there was no difference between the groups neither in age nor in the duration of chronic constipation symptoms. At the follow-up, 3 months later, clinical gains were maintained. This study demonstrates that the EMG-BF is an effective behavioral therapy for the treatment of dyssynergic defecation in community-dwelling elderly women.

  5. Balance Improvement Effects of Biofeedback Systems with State-of-the-Art Wearable Sensors: A Systematic Review

    Science.gov (United States)

    Ma, Christina Zong-Hao; Wong, Duo Wai-Chi; Lam, Wing Kai; Wan, Anson Hong-Ping; Lee, Winson Chiu-Chun

    2016-01-01

    Falls and fall-induced injuries are major global public health problems. Balance and gait disorders have been the second leading cause of falls. Inertial motion sensors and force sensors have been widely used to monitor both static and dynamic balance performance. Based on the detected performance, instant visual, auditory, electrotactile and vibrotactile biofeedback could be provided to augment the somatosensory input and enhance balance control. This review aims to synthesize the research examining the effect of biofeedback systems, with wearable inertial motion sensors and force sensors, on balance performance. Randomized and non-randomized clinical trials were included in this review. All studies were evaluated based on the methodological quality. Sample characteristics, device design and study characteristics were summarized. Most previous studies suggested that biofeedback devices were effective in enhancing static and dynamic balance in healthy young and older adults, and patients with balance and gait disorders. Attention should be paid to the choice of appropriate types of sensors and biofeedback for different intended purposes. Maximizing the computing capacity of the micro-processer, while minimizing the size of the electronic components, appears to be the future direction of optimizing the devices. Wearable balance-improving devices have their potential of serving as balance aids in daily life, which can be used indoors and outdoors. PMID:27023558

  6. Balance Improvement Effects of Biofeedback Systems with State-of-the-Art Wearable Sensors: A Systematic Review.

    Science.gov (United States)

    Ma, Christina Zong-Hao; Wong, Duo Wai-Chi; Lam, Wing Kai; Wan, Anson Hong-Ping; Lee, Winson Chiu-Chun

    2016-03-25

    Falls and fall-induced injuries are major global public health problems. Balance and gait disorders have been the second leading cause of falls. Inertial motion sensors and force sensors have been widely used to monitor both static and dynamic balance performance. Based on the detected performance, instant visual, auditory, electrotactile and vibrotactile biofeedback could be provided to augment the somatosensory input and enhance balance control. This review aims to synthesize the research examining the effect of biofeedback systems, with wearable inertial motion sensors and force sensors, on balance performance. Randomized and non-randomized clinical trials were included in this review. All studies were evaluated based on the methodological quality. Sample characteristics, device design and study characteristics were summarized. Most previous studies suggested that biofeedback devices were effective in enhancing static and dynamic balance in healthy young and older adults, and patients with balance and gait disorders. Attention should be paid to the choice of appropriate types of sensors and biofeedback for different intended purposes. Maximizing the computing capacity of the micro-processer, while minimizing the size of the electronic components, appears to be the future direction of optimizing the devices. Wearable balance-improving devices have their potential of serving as balance aids in daily life, which can be used indoors and outdoors.

  7. Real-time visual biofeedback during weight bearing improves therapy compliance in patients following lower extremity fractures

    NARCIS (Netherlands)

    Raaben, Marco; Holtslag, Herman R; Leenen, Luke P H; Augustine, Robin; Blokhuis, Taco J

    BACKGROUND: Individuals with lower extremity fractures are often instructed on how much weight to bear on the affected extremity. Previous studies have shown limited therapy compliance in weight bearing during rehabilitation. In this study we investigated the effect of real-time visual biofeedback

  8. Real-time visual biofeedback during weight bearing improves therapy compliance in patients following lower extremity fractures

    NARCIS (Netherlands)

    Raaben, Marco; Holtslag, Herman R.; Leenen, Luke P. H.; Augustine, Robin; Blokhuis, Taco J.

    2017-01-01

    Individuals with lower extremity fractures are often instructed on how much weight to bear on the affected extremity. Previous studies have shown limited therapy compliance in weight bearing during rehabilitation. In this study we investigated the effect of real-time visual biofeedback on weight

  9. Balance Improvement Effects of Biofeedback Systems with State-of-the-Art Wearable Sensors: A Systematic Review

    Directory of Open Access Journals (Sweden)

    Christina Zong-Hao Ma

    2016-03-01

    Full Text Available Falls and fall-induced injuries are major global public health problems. Balance and gait disorders have been the second leading cause of falls. Inertial motion sensors and force sensors have been widely used to monitor both static and dynamic balance performance. Based on the detected performance, instant visual, auditory, electrotactile and vibrotactile biofeedback could be provided to augment the somatosensory input and enhance balance control. This review aims to synthesize the research examining the effect of biofeedback systems, with wearable inertial motion sensors and force sensors, on balance performance. Randomized and non-randomized clinical trials were included in this review. All studies were evaluated based on the methodological quality. Sample characteristics, device design and study characteristics were summarized. Most previous studies suggested that biofeedback devices were effective in enhancing static and dynamic balance in healthy young and older adults, and patients with balance and gait disorders. Attention should be paid to the choice of appropriate types of sensors and biofeedback for different intended purposes. Maximizing the computing capacity of the micro-processer, while minimizing the size of the electronic components, appears to be the future direction of optimizing the devices. Wearable balance-improving devices have their potential of serving as balance aids in daily life, which can be used indoors and outdoors.

  10. Technical Aspects and Validation of a New Biofeedback System for Measuring Lower Limb Loading in the Dynamic Situation

    NARCIS (Netherlands)

    Raaben, Marco; Holtslag, Herman R.; Augustine, Robin; van Merkerk, Rutger O.; Koopman, Bart F. J. M.; Blokhuis, Taco J.

    2017-01-01

    A variety of techniques for measuring lower limb loading exists, each with their own limitations. A new ambulatory biofeedback system was developed to overcome these limitations. In this study, we described the technical aspects and validated the accuracy of this system. A bench press was used to

  11. Technical Aspects and Validation of a New Biofeedback System for Measuring Lower Limb Loading in the Dynamic Situation

    NARCIS (Netherlands)

    Raaben, M.; Holtslag, H.R.; Augustine, R.; van Merkerk, R.O.; Koopman, Hubertus F.J.M.; Blokhuis, T.J.

    2017-01-01

    Background: A variety of techniques for measuring lower limb loading exists, each with their own limitations. A new ambulatory biofeedback system was developed to overcome these limitations. In this study, we described the technical aspects and validated the accuracy of this system. Methods: A bench

  12. Breathing biofeedback as an adjunct to exposure in cognitive behavioral therapy hastens the reduction of PTSD symptoms : a pilot study

    NARCIS (Netherlands)

    Rosaura Polak, A; Witteveen, Anke B; Denys, D.; Olff, Miranda

    Although trauma-focused cognitive behavioral therapy (TF-CBT) with exposure is an effective treatment for posttraumatic stress disorder (PTSD), not all patients recover. Addition of breathing biofeedback to exposure in TF-CBT is suggested as a promising complementary technique to improve recovery of

  13. Breathing biofeedback as an adjunct to exposure in cognitive behavioral therapy hastens the reduction of PTSD symptoms: a pilot study

    NARCIS (Netherlands)

    Rosaura Polak, A.; Witteveen, Anke B.; Denys, Damiaan; Olff, Miranda

    2015-01-01

    Although trauma-focused cognitive behavioral therapy (TF-CBT) with exposure is an effective treatment for posttraumatic stress disorder (PTSD), not all patients recover. Addition of breathing biofeedback to exposure in TF-CBT is suggested as a promising complementary technique to improve recovery of

  14. PP-4 ANORECTAL MALFORMATIONS: MOTILITY STUDIES AND RESPONSE TO BIOFEEDBACK THERAPY.

    Science.gov (United States)

    Bigliardi, Roman N; Ditaranto, A; Reynoso, R; Vidal, J H; Messere, G; Toca, M; Silvestri, G; Ortiz, G; Noriega, S; Varela, A

    2015-10-01

    Anorectal malformations (ARM) are infrequent anatomic defects with a prevalence of 1 each 5000 alive newborns. Most of the patients repaired of this illness have some degree of constipation or fecal incontinence. There are few reports about manometric studies and biofeedback treatment in patients with anorectal malformations. To evaluate of our population's anorectal functionality late after surgery by anorectal manometry; To study the response to diet, toilet training, and/or biofeedback. Anorectal manometry was done in 39 patients with ARM and 35 of them received combinated treatment of diet, toilet training and biofeedback. Age: 6 to 17 years old. Mean age: 8.05 years. Descriptive study. From april 2004 to april 2015. 14 patients had high malformations(36%), 18 had low malformations(46%) and 7 had cloaca(18%). children over 6 years of age with anorectal malformation operated using Peña's technique (postsagittal anorectoplasty). patients with neurological disorders that do not non-compliant with study and treatment indications. Average resting pressure was 28 mmHg(High level 25,5 and Low level 29,8 mmHg), range between 7 and 51 mmHg. Squeezing pressure between 29 and 120 mmHg(mean:69mmHg). Combined treatment of diet, toilet training, and biofeedback was succesfull to get total continence in 22 patients (4 cloacas, 10 high malformations and 8 low malformations), partial continence in 6(all low) and without response in 3(1 low, 1 high and 1 cloaca); 2 patients archived continence only with toilet training and 2 were lost in follow up(T.Fisher: 0,1). In high ARM 8 had positive(+) rectoanal inhibitory reflex(RAIR) and 6 negative(¬). In cloacas it was (+) in 3, (¬) in 3 and doubtful in 1. In low ARM 15(+), 2 (¬) and 1 doubtful. Reflex was obtained with 20 to 60cc of air(mean 31,36). The RRAI duration was 10 to 17 seconds(mean: 13 seconds).From 22 total continent, RAIR was (+) in 13, (¬) in 7 and hazardous in 2. All 6 partially continent had (+) RAIR; and from 3

  15. gamma. -relaxation process in crystallizable polymers

    Energy Technology Data Exchange (ETDEWEB)

    Mindiyarov, Kh G; Zelenev, Yu V; Bartenev, G M [Birskij Gosudarstvennyj Pedagogicheskij Inst. (USSR)

    1975-07-01

    In the present paper, with the aid of radiothermoluminescence technique ..gamma..-relaxation processes are investigated, which are conditioned by molecular mobility and are associated with defects in the crystalline structure of polymers PEh, PP, and elastomers PIB, NK, SKD, SKI exposed to ..gamma..-rays of Co/sup 60/ at a dose rate of 1 Mrad. The shape of the thermoluminescence curve, i.e. the luminescence intensity in the ..cap alpha.. - ..gamma..-maxima, their relationship, position with respect to temperature are strongly dependent on the degree of crystallinity, on the thermal and mechanical prehistory. In highly crystalline samples of PEh and PP ..cap alpha..-maximum may be absent. Dependence has been studied of the luminescence intensity in the ..cap alpha..- and ..gamma..-maxima (Isub(..cap alpha..)/Isub(..gamma..)) on the crystallization temperature; the curve passes through the minimum when the crystallization rate is maximum. The relationship Isub(..gamma..)re of crystallinity degree.

  16. Peeling mode relaxation ELM model

    International Nuclear Information System (INIS)

    Gimblett, C. G.

    2006-01-01

    This paper discusses an approach to modelling Edge Localised Modes (ELMs) in which toroidal peeling modes are envisaged to initiate a constrained relaxation of the tokamak outer region plasma. Relaxation produces both a flattened edge current profile (which tends to further destabilise a peeling mode), and a plasma-vacuum negative current sheet which has a counteracting stabilising influence; the balance that is struck between these two effects determines the radial extent (rE) of the ELM relaxed region. The model is sensitive to the precise position of the mode rational surfaces to the plasma surface and hence there is a 'deterministic scatter' in the results that has an accord with experimental data. The toroidal peeling stability criterion involves the edge pressure, and using this in conjunction with predictions of rE allows us to evaluate the ELM energy losses and compare with experiment. Predictions of trends with the edge safety factor and collisionality are also made

  17. Young, healthy subjects can reduce the activity of calf muscles when provided with EMG biofeedback in upright stance

    Directory of Open Access Journals (Sweden)

    Taian M. Vieira

    2016-04-01

    Full Text Available Recent evidence suggests the minimisation of muscular effort rather than of the size of bodily sway may be the primary, nervous system goal when regulating the human, standing posture. Different programs have been proposed for balance training; none however has been focused on the activation of postural muscles during standing. In this study we investigated the possibility of minimising the activation of the calf muscles during standing through biofeedback. By providing subjects with an audio signal that varied in amplitude and frequency with the amplitude of surface electromyograms (EMG recorded from different regions of the gastrocnemius and soleus muscles, we expected them to be able to minimise the level of muscle activation during standing without increasing the excursion of the centre of pressure (CoP. CoP data and surface EMG from gastrocnemii, soleus and tibialis anterior muscles were obtained from ten healthy participants while standing at ease and while standing with EMG biofeedback. Four sensitivities were used to test subjects’ responsiveness to the EMG biofeedback. Compared with standing at ease, the two most sensitive feedback conditions induced a decrease in plantar flexor activity (~15%; P<0.05 and an increase in tibialis anterior EMG (~10%; P<0.05. Furthermore, CoP mean position significantly shifted backward (~30 mm. In contrast, the use of less sensitive EMG biofeedback resulted in a significant decrease in EMG activity of ankle plantar flexors with a marginal increase in TA activity compared with standing at ease. These changes were not accompanied by greater CoP displacements or significant changes in mean CoP position. Key results revealed subjects were able to keep standing stability while reducing the activity of gastrocnemius and soleus without loading their tibialis anterior muscle when standing with EMG biofeedback. These results may therefore posit the basis for the development of training protocols aimed at

  18. Relationship between dysfunctional breathing patterns and ability to achieve target heart rate variability with features of "coherence" during biofeedback.

    Science.gov (United States)

    Courtney, Rosalba; Cohen, Marc; van Dixhoorn, Jan

    2011-01-01

    Heart rate variability (HRV) biofeedback is a self-regulation strategy used to improve conditions including asthma, stress, hypertension, and chronic obstructive pulmonary disease. Respiratory muscle function affects hemodynamic influences on respiratory sinus arrhythmia (RSA), and HRV and HRV-biofeedback protocols often include slow abdominal breathing to achieve physiologically optimal patterns of HRV with power spectral distribution concentrated around the 0.1-Hz frequency and large amplitude. It is likely that optimal balanced breathing patterns and ability to entrain heart rhythms to breathing reflect physiological efficiency and resilience and that individuals with dysfunctional breathing patterns may have difficulty voluntarily modulating HRV and RSA. The relationship between breathing movement patterns and HRV, however, has not been investigated. This study examines how individuals' habitual breathing patterns correspond with their ability to optimize HRV and RSA. Breathing pattern was assessed using the Manual Assessment of Respiratory Motion (MARM) and the Hi Lo manual palpation techniques in 83 people with possible dysfunctional breathing before they attempted HRV biofeedback. Mean respiratory rate was also assessed. Subsequently, participants applied a brief 5-minute biofeedback protocol, involving breathing and positive emotional focus, to achieve HRV patterns proposed to reflect physiological "coherence" and entrainment of heart rhythm oscillations to other oscillating body systems. Thoracic-dominant breathing was associated with decreased coherence of HRV (r = -.463, P = .0001). Individuals with paradoxical breathing had the lowest HRV coherence (t(8) = 10.7, P = .001), and the negative relationship between coherence of HRV and extent of thoracic breathing was strongest in this group (r = -.768, P = .03). Dysfunctional breathing patterns are associated with decreased ability to achieve HRV patterns that reflect cardiorespiratory efficiency and

  19. Biofeedback in Partial Weight Bearing: Usability of Two Different Devices from a Patient's and Physical Therapist's Perspective.

    Science.gov (United States)

    van Lieshout, Remko; Pisters, Martijn F; Vanwanseele, Benedicte; de Bie, Rob A; Wouters, Eveline J; Stukstette, Mirelle J

    2016-01-01

    Partial weight bearing is frequently instructed by physical therapists in patients after lower-limb trauma or surgery. The use of biofeedback devices seems promising to improve the patient's compliance with weight-bearing instructions. SmartStep and OpenGo-Science are biofeedback devices that provide real-time feedback. For a successful implementation, usability of the devices is a critical aspect and should be tested from a user's perspective. To describe the usability from the physical therapists' and a patients' perspective of Smartstep and OpenGo-Science to provide feedback on partial weight bearing during supervised rehabilitation of patients after lower-limb trauma or surgery. In a convergent mixed-methods design, qualitative and quantitative data were collected. Usability was subdivided into user performance, satisfaction and acceptability. Patients prescribed with partial weight bearing and their physical therapists were asked to use SmartStep and OpenGo-Science during supervised rehabilitation. Usability was qualitatively tested by a think-aloud method and a semi-structured interview and quantitatively tested by the System-Usability-Scale (SUS) and closed questions. For the qualitative data thematic content analyses were used. Nine pairs of physical therapists and their patients participated. The mean SUS scores for patients and physical therapists were for SmartStep 70 and 53, and for OpenGo-Science 79 and 81, respectively. Scores were interpreted with the Curved Grading Scale. The qualitative data showed that there were mixed views and perceptions from patients and physical therapists on satisfaction and acceptability. This study gives insight in the usability of two biofeedback devices from the patient's and physical therapist's perspective. The overall usability from both perspectives seemed to be acceptable for OpenGo-Science. For SmartStep, overall usability seemed only acceptable from the patient's perspective. The study findings could help

  20. Randomised controlled trial of brief intervention with biofeedback and hypnotherapy in patients with refractory irritable bowel syndrome.

    Science.gov (United States)

    Dobbin, A; Dobbin, J; Ross, S C; Graham, C; Ford, M J

    2013-01-01

    Irritable bowel syndrome (IBS) is a common disorder associated with profoundly impaired quality of life and emotional distress. The management of refractory IBS symptoms remains challenging and non-pharmacological therapeutic approaches have been shown to be effective. We compared brief interventions with biofeedback and hypnotherapy in women referred by their GP with refractory IBS symptoms. Patients were randomised to one of two treatment groups, biofeedback or hypnotherapy, delivered as three one-hour sessions over 12 weeks. Symptom assessments were undertaken using validated, self-administered questionnaires. Two of the 128 consecutive IBS patients suitable for the study declined to consider nonpharmacological therapy and 29 patients did not attend beyond the first session. Of the 97 patients randomised into the study, 21 failed to attend the therapy session; 15 of 76 patients who attended for therapy dropped out before week 12 post-therapy. The mean (SD) change in IBS symptom severity score 12 weeks post-treatment in the biofeedback group was -116.8 (99.3) and in the hypnotherapy group -58.0 (101.1), a statistically significant difference between groups (difference=-58.8, 95% confidence interval [CI] for difference [-111.6, -6.1], p=0.029). In 61 patients with refractory IBS, biofeedback and hypnotherapy were equally effective at improving IBS symptom severity scores, total non-gastrointestinal symptom scores and anxiety and depression ratings during 24 weeks follow-up. Biofeedback may prove to be the more cost-effective option as it requires less expertise.

  1. Experiments and Modeling of Si-Ge Interdiffusion with Partial Strain Relaxation in Epitaxial SiGe Heterostructures

    KAUST Repository

    Dong, Y.

    2014-07-26

    Si-Ge interdiffusion and strain relaxation were studied in a metastable SiGe epitaxial structure. With Ge concentration profiling and ex-situ strain analysis, it was shown that during thermal anneals, both Si-Ge interdiffusion and strain relaxation occurred. Furthermore, the time evolutions of both strain relaxation and interdiffusion were characterized. It showed that during the ramp-up stage of thermal anneals at higher temperatures (800°C and 840°C), the degree of relaxation, R, reached a “plateau”, while interdiffusion was negligible. With the approximation that the R value is constant after the ramp-up stage, a quantitative interdiffusivity model was built to account for both the effect of strain relaxation and the impact of the relaxation induced dislocations, which gave good agreement with the experiment data.

  2. Phonon conductivity and relaxation rate in solids with disturbances by the Green function method

    International Nuclear Information System (INIS)

    Singh, M.

    1980-09-01

    In this present article we have established an expression for the temperature dependence of the lattice thermal conductivity of solids with harmonic disturbances. The relaxation rate for scattering of phonons with point defect is also derived. We will apply the Kubo-correlation function formalism for the thermal conductivity, and the double time temperature dependent Green function technique for the evaluation of correlation functions

  3. Criteria for accurate determination of the magnon relaxation length from the nonlocal spin Seebeck effect

    NARCIS (Netherlands)

    Shan, Juan; Cornelissen, Ludo Johannes; Liu, Jing; Ben Youssef, J.; Liang, Lei; van Wees, Bart

    2017-01-01

    The nonlocal transport of thermally generated magnons not only unveils the underlying mechanism of the spin Seebeck effect, but also allows for the extraction of the magnon relaxation length (λm) in a magnetic material, the average distance over which thermal magnons can propagate. In this study, we

  4. Relaxation properties in classical diamagnetism

    Science.gov (United States)

    Carati, A.; Benfenati, F.; Galgani, L.

    2011-06-01

    It is an old result of Bohr that, according to classical statistical mechanics, at equilibrium a system of electrons in a static magnetic field presents no magnetization. Thus a magnetization can occur only in an out of equilibrium state, such as that produced through the Foucault currents when a magnetic field is switched on. It was suggested by Bohr that, after the establishment of such a nonequilibrium state, the system of electrons would quickly relax back to equilibrium. In the present paper, we study numerically the relaxation to equilibrium in a modified Bohr model, which is mathematically equivalent to a billiard with obstacles, immersed in a magnetic field that is adiabatically switched on. We show that it is not guaranteed that equilibrium is attained within the typical time scales of microscopic dynamics. Depending on the values of the parameters, one has a relaxation either to equilibrium or to a diamagnetic (presumably metastable) state. The analogy with the relaxation properties in the Fermi Pasta Ulam problem is also pointed out.

  5. Onsager relaxation of toroidal plasmas

    International Nuclear Information System (INIS)

    Samain, A.; Nguyen, F.

    1997-01-01

    The slow relaxation of isolated toroidal plasmas towards their thermodynamical equilibrium is studied in an Onsager framework based on the entropy metric. The basic tool is a variational principle, equivalent to the kinetic equation, involving the profiles of density, temperature, electric potential, electric current. New minimization procedures are proposed to obtain entropy and entropy production rate functionals. (author)

  6. Anisotropic spin relaxation in graphene

    NARCIS (Netherlands)

    Tombros, N.; Tanabe, S.; Veligura, A.; Jozsa, C.; Popinciuc, M.; Jonkman, H. T.; van Wees, B. J.

    2008-01-01

    Spin relaxation in graphene is investigated in electrical graphene spin valve devices in the nonlocal geometry. Ferromagnetic electrodes with in-plane magnetizations inject spins parallel to the graphene layer. They are subject to Hanle spin precession under a magnetic field B applied perpendicular

  7. Stochastic and Chaotic Relaxation Oscillations

    NARCIS (Netherlands)

    Grasman, J.; Roerdink, J.B.T.M.

    1988-01-01

    For relaxation oscillators stochastic and chaotic dynamics are investigated. The effect of random perturbations upon the period is computed. For an extended system with additional state variables chaotic behavior can be expected. As an example, the Van der Pol oscillator is changed into a

  8. Tensions relaxation in Zircaloy-4

    International Nuclear Information System (INIS)

    Cuniberti, A.M.; Picasso, A.C.

    1990-01-01

    Traction and stress relaxation studies were performed on polycrystalline Zry-4 at room temperature. The effect of loading velocity on the plastic behaviour of the material is discussed, analysing log σ vs. log dε/dt at different deformation levels. The contribution introduced by the testing machine was taken into account in data evaluation. (Author). 7 refs., 3 figs., 3 tabs

  9. Epileptic Seizures are Reduced by Autonomic Biofeedback Therapy Through Enhancement of Fronto-limbic Connectivity: A Controlled Trial and Neuroimaging Study

    Directory of Open Access Journals (Sweden)

    Yoko Nagai

    2018-01-01

    Interpretation: Our clinical study provides evidence for autonomic biofeedback therapy as an effective and potent behavioral intervention for patients with drug-resistant epilepsy. This approach is non-pharmacological, non-invasive and seemingly side-effect free.

  10. A Pilot Study on Measuring the Readers’ Emotions Using HRV Biofeedback at University Malaysia Pahang

    Directory of Open Access Journals (Sweden)

    Iftikhar Yousaf

    2016-11-01

    Full Text Available Positive associations have been found between reading and emotions. Various techniques, including traditional as well as modern, have been used to measure emotions in the previous studies. However, emotional measurement of the readers of a literary piece through HRV Biofeedback has never been investigated. A study was undertaken to assess whether Heart Rate Variability (HRV biofeedback regarding  measurement of emotions in the readers of English Literature is likely to be effective or not for the first time at University Malaysia Pahang. In this study two scripts of the plays “Dr. Faustus” and “Waiting for Godot” were used. The Scripts were prepared from the Original Texts of these two plays, which might convey the overall message of the plays to the readers and resultantly produce the desired effect on the readers’ emotions. The total words of these two scripts were around 1050 each, allowing the students to complete one script in 7-8 minutes. Six subjects were selected randomly. While they were sitting calm and quiet at the desk, photoplethysmograph sensor was attached to their one of the earlobes which was connected to the emWave Desktop-PC software to record their Baseline HRV. The subjects, one at a time, read the Script 1 “Waiting for Godot” silently. After completion of the reading of Script 1, the emWave software was stopped and the HRV of the subject was recorded and saved automatically in the computer. The same process was repeated with Script 2 “Dr. Faustus”. In this way, emWave software recorded three HRV data for every subject. Results show obvious changes and significant correlations in the HRV of the participants while reading both the scripts. VLF increased for Script 1 while it decreased for Script 2. On the other hand, HF increased for Script 1 and further increased for Script 2.  LF decreased for Script 1 and increased for Script 2. These results point out the tendency that the stress level of the

  11. Sleep, Stress & Relaxation: Rejuvenate Body & Mind

    Science.gov (United States)

    Sleep, Stress & Relaxation: Rejuvenate Body & Mind; Relieve Stress; best ways to relieve stress; best way to relieve stress; different ways to relieve stress; does smoking relieve stress; does tobacco relieve stress; how can I relieve stress; how can you relieve stress; how do I relieve stress; reduce stress; does smoking reduce stress; how can I reduce stress; how to reduce stress; reduce stress; reduce stress levels; reducing stress; smoking reduce stress; smoking reduces stress; stress reducing techniques; techniques to reduce stress; stress relief; best stress relief; natural stress relief; need stress relief; relief for stress; relief from stress; relief of stress; smoking and stress relief; smoking for stress relief; smoking stress relief; deal with stress; dealing with stress; dealing with anger; dealing with stress; different ways of dealing with stress; help dealing with stress; how to deal with anger; how to deal with stress; how to deal with stress when quitting smoking; stress management; free stress management; how can you manage stress; how do you manage stress; how to manage stress; manage stress; management of stress; management stress; managing stress; strategies for managing stress; coping with stress; cope with stress; copeing with stress; coping and stress; coping skills for stress; coping strategies for stress; coping strategies with stress; coping strategy for stress; coping with stress; coping with stress and anxiety; emotional health; emotional health; emotional health article; emotional health articles; deep relaxation; deep breathing relaxation techniques; deep muscle relaxation; deep relaxation; deep relaxation meditation; deep relaxation technique; deep relaxation techniques; meditation exercises; mindful exercises; mindful meditation exercises; online relaxation exercises; relaxation breathing exercises; relaxation exercise; relaxation exercises; stress relaxation; methods of relaxation for stress; relax stress; relax techniques stress

  12. Effect of the Magnus force on skyrmion relaxation dynamics

    Science.gov (United States)

    Brown, Barton L.; Täuber, Uwe C.; Pleimling, Michel

    2018-01-01

    We perform systematic Langevin molecular dynamics simulations of interacting skyrmions in thin films. The interplay between the Magnus force, the repulsive skyrmion-skyrmion interaction, and the thermal noise yields different regimes during nonequilibrium relaxation. In the noise-dominated regime, the Magnus force enhances the disordering effects of the thermal noise. In the Magnus-force-dominated regime, the Magnus force cooperates with the skyrmion-skyrmion interaction to yield a dynamic regime with slow decaying correlations. These two regimes are characterized by different values of the aging exponent. In general, the Magnus force accelerates the approach to the steady state.

  13. IVABRADINE AND QUALITY OF BIOFEEDBACK IN THE LOOP OF PACED BREATHING UNDER THE CONTROL OF HEART RATE VARIABILITY PARAMETERS IN HEALTHY VOLUNTEERS

    Directory of Open Access Journals (Sweden)

    S. A. S. Belal

    2013-06-01

    Full Text Available On 15 healthy volunteers aged from 18 to 22 years the effect of ivabradine on the quality of biofeedback in the loop of paced breathing under the control of heart rate variability parameters were estimated. It was found that ivabradine contributes to an earlier onset and more significant optimization of regulatory systems in systematic sessions of biofeedback that allows to expand the indications for its clinical use.

  14. Influence of sphincter defect on biofeedback outcomes in patients with fecal incontinence

    Directory of Open Access Journals (Sweden)

    Roberto L. Kaiser, Junior

    2014-04-01

    Full Text Available Objective: to evaluate the effect of sphincter defect (SD on biofeedback (BF response in patients with fecal incontinence. Methods: two hundred and forty-two patients with fecal incontinence undergoing BF as exclusive treatment were identified from a BF database. Patients were evaluated with fecal incontinence score (Cleveland Clinic Florida – Fecal Incontinence Score, CCF-FI and anorectal physiology tests. The pre- and immediate post-treatment outcomes were obtained from the chart, and the long-term outcomes by CCF-FI score that was sent by mail. Results: 242 patients underwent BF for fecal incontinence. 143 (59.1% underwent ultrasonography, 43 (30.1% of whom had sphincter defect detected on US. The immediate outcomes were not affected by the presence of absence of SD. The second CCF-FI questionnaire was mailed after a mean of 6.1 years after treatment. 31 (57.4% exhibited improvement, 4 (7.4% remained unchanged, and 19 (35.2% had worsening function, which was significantly inferior in patients with SD (p = 0.021. Electromyography demonstrated increased electrical activity in the contraction phase after BF in both groups. Conclusions: the majority of patients experience improvement in fecal incontinence after BF. However, patients with SD detected on US prior to treatment seem to have worse function at long term. Resumo: Objetivos: avaliar a influência do defeito esfincteriano (DE na resposta ao biofeedback (BF em pacientes com incontinência fecal. Métodos: 242 pacientes com incontinência fecal, submetidos exclusivamente ao BF como forma de tratamento, foram selecionados. Os pacientes foram submetidos ao escore de incontinência fecal (Cleveland Clinic Flórida-Escore de Incontinência Fecal, CCF-IF e testes de investigação da fisiologia anorretal. O pré e pós-tratamento imediato foram obtidos do prontuário e para avaliação a longo prazo foi enviado o CCF-IF pelo correio. Resultados: 242 pacientes realizaram BF. 143 (59

  15. Heart rate regulation during cycle-ergometer exercise via bio-feedback.

    Science.gov (United States)

    Argha, Ahmadreza; Su, Steven W; Hung Nguyen; Celler, Branko G

    2015-08-01

    This paper explains our developed control system which regulates the heart rate (HR) to track a desired trajectory. The controller is indeed a non-conventional non-model-based proportional, integral and derivative (PID) controller. The controller commands are interpreted as biofeedback auditory commands. These commands can be heard and implemented by the exercising subject as a part of the control-loop. However, transmitting a feedback signal while the pedals are not in the appropriate position to efficiently exert force may lead to a cognitive disengagement of the user from the feedback controller. This note explains a novel form of control system regarding as "actuator-based event-driven control system", designed specifically for the purpose of this project. We conclude that the developed event-driven controller makes it possible to precisely regulate HR to a predetermined HR profile.

  16. Bio-feedback treatment of fecal incontinence: where are we, and where are we going?

    Science.gov (United States)

    Chiarioni, Giuseppe; Ferri, Barbara; Morelli, Antonio; Iantorno, Guido; Bassotti, Gabrio

    2005-08-21

    Fecal incontinence is a disabling disease, often observed in young subjects, that may have devastating psycho-social consequences. In the last years, numerous evidences have been reported on the efficacy of bio-feedback techniques for the treatment of this disorder. Overall, the literature data claim a success rate in more than 70% of cases in the short term. However, recent controlled trials have not confirmed this optimistic view, thus emphasizing the role of standard care. Nonetheless, many authors believe that this should be the first therapeutic approach for fecal incontinence due to the efficacy, lack of side-effects, and scarce invasiveness. Well-designed randomized, controlled trial are eagerly awaited to solve this therapeutic dilemma.

  17. Developing wearable bio-feedback systems: a general-purpose platform.

    Science.gov (United States)

    Bianchi, Luigi; Babiloni, Fabio; Cincotti, Febo; Arrivas, Marco; Bollero, Patrizio; Marciani, Maria Grazia

    2003-06-01

    Microprocessors, even those in PocketPCs, have adequate power for many real-time biofeedback applications for disabled people. This power allows design of portable or wearable devices that are smaller and lighter, and that have longer battery life compared to notebook-based systems. In this paper, we discuss a general-purpose hardware/software solution based on industrial or consumer devices and a C++ framework. Its flexibility and modularity make it adaptable to a wide range of situations. Moreover, its design minimizes system requirements and programming effort, thus allowing efficient systems to be built quickly and easily. Our design has been used to build two brain computer interface systems that were easily ported from the Win32 platform.

  18. Improving Managers' Psychophysical Well-Being: Effectiveness of Respiratory Sinus Arrhythmia Biofeedback.

    Science.gov (United States)

    Munafò, Marianna; Patron, Elisabetta; Palomba, Daniela

    2016-06-01

    High work stress has been consistently associated with disturbed autonomic balance, specifically, lowered vagal cardiac control and increased sympathetic activity, which may lead to increased cardiovascular risk. Stress management procedures have been proposed to reduce autonomic dysfunctions related to work stress in different categories of workers exposed to heightened work demands, while a limited number of studies addressed this issue in managers. The present study was aimed at evaluating the effectiveness of a respiratory sinus arrhythmia (RSA) biofeedback (BF) intervention on psychological and physiological outcomes, in managers with high-level work responsibilities. Thirty-one managers leading outstanding private or public companies were randomly assigned to either a RSA-BF training (RSA-BF; N = 16) or a control group (N = 15). The RSA-BF training consisted of five weekly 45 min sessions, designed to increase RSA, whereas controls had to provide a daily stress diary once a week. After the training, managers in both groups reported reduced heart rate at rest, lower anxiety levels and improvement in health-related quality of life. More importantly, managers in the RSA-BF group showed increased vagal control (as indexed by increased RSA), decreased sympathetic arousal (as indexed by reduced skin conductance and systolic blood pressure) and lower emotional interferences, compared to managers in the control group. Results from this study showed that RSA-BF training was effective in improving cardiac autonomic balance at rest. Moreover, findings from this study underline the effectiveness of biofeedback in reducing psychophysiological negative outcomes associated with stress in managers.

  19. Relaxation Techniques to Manage IBS Symptoms

    Science.gov (United States)

    ... for 15–20 seconds and then begin again. Progressive Muscle Relaxation This method of relaxation focuses on ... helpful, please consider supporting IFFGD with a small tax- deductible donation. Make Donation Adapted from IFFGD Publication # ...

  20. Relaxation and Distraction in Experimental Desensitization.

    Science.gov (United States)

    Weir, R. O.; Marshall, W. L.

    1980-01-01

    Compared experimental desensitization with a procedure that replaced relaxation with a distraction task and with an approach that combined both relaxation and distraction. Desensitization generally was more effective than the other two procedures. (Author)

  1. Relaxation as a Factor in Semantic Desensitization

    Science.gov (United States)

    Bechtel, James E.; McNamara, J. Regis

    1975-01-01

    Relaxation and semantic desensitization were used to alleviate the fear of phobic females. Results showed that semantic desensitization, alone or in combination with relaxation, failed to modify the evaluative meanings evoked by the feared object. (SE)

  2. Plasmon-mediated energy relaxation in graphene

    Energy Technology Data Exchange (ETDEWEB)

    Ferry, D. K. [School of Electrical, Computer, and Energy Engineering, Arizona State University, Tempe, Arizona 85287-5706 (United States); Somphonsane, R. [Department of Physics, King Mongkut' s Institute of Technology, Ladkrabang, Bangkok 10520 (Thailand); Ramamoorthy, H.; Bird, J. P. [Department of Electrical Engineering, University at Buffalo, the State University of New York, Buffalo, New York 14260-1500 (United States)

    2015-12-28

    Energy relaxation of hot carriers in graphene is studied at low temperatures, where the loss rate may differ significantly from that predicted for electron-phonon interactions. We show here that plasmons, important in the relaxation of energetic carriers in bulk semiconductors, can also provide a pathway for energy relaxation in transport experiments in graphene. We obtain a total loss rate to plasmons that results in energy relaxation times whose dependence on temperature and density closely matches that found experimentally.

  3. Biofeedback and the electromyographic activity of pelvic floor muscles in pregnant women Biofeedback na atividade eletromiográfica dos músculos do assoalho pélvico em gestantes

    Directory of Open Access Journals (Sweden)

    Roberta L. A. Batista

    2011-10-01

    Full Text Available BACKGROUND: Maintaining continence is among the functions of the pelvic floor muscles (PFM and their dysfunction can cause urinary incontinence (UI, which is a common occurrence during pregnancy and the puerperal period. Pelvic floor muscle training (PFMT, therefore, is important during pregnancy, although most women perform the muscle contractions unsatisfactorily. OBJECTIVES: This study is an exploratory analysis of the results of three electromyographic (EMG activity biofeedback sessions in pregnant women. METHODS: The study sample included 19 nulliparous women with low risk pregnancies. The participants performed three sessions of EMG biofeedback consisting of slow and fast contractions. The average value of the normalized amplitudes of surface electromyography was used to evaluate the results. The linear regression model with mixed effects was used for statistical analysis, with the EMG data normalized by maximum voluntary contraction (MVC. RESULTS: A steady increase in EMG amplitude was observed during each contraction and by the end of the biofeedback sessions, although this difference was only significant when comparing the first tonic contraction of each session (p=0.03. CONCLUSIONS: The results indicate that three sessions of training with biofeedback improved PFM EMG activity during the second trimester in women with low-risk pregnancies. The effectiveness of this protocol should be further investigated in randomized controlled trials.CONTEXTUALIZAÇÃO: Dentre as funções dos músculos do assoalho pélvico (MAPs, pode-se citar a manutenção da continência, sendo que sua disfunção pode causar a incontinência urinária (IU, muito frequente no período gestacional e no puerpério. Diante disso, se faz importante o treinamento dos músculos do assoalho pélvico (TMAP durante o período gestacional, entretanto grande parte das mulheres realiza a contração dessa musculatura de maneira insatisfatória. OBJETIVOS: Realizar uma an

  4. Nonlinear Relaxation in Population Dynamics

    Science.gov (United States)

    Cirone, Markus A.; de Pasquale, Ferdinando; Spagnolo, Bernardo

    We analyze the nonlinear relaxation of a complex ecosystem composed of many interacting species. The ecological system is described by generalized Lotka-Volterra equations with a multiplicative noise. The transient dynamics is studied in the framework of the mean field theory and with random interaction between the species. We focus on the statistical properties of the asymptotic behaviour of the time integral of the ith population and on the distribution of the population and of the local field.

  5. The Effects of Suggestibility on Relaxation.

    Science.gov (United States)

    Rickard, Henry C.; And Others

    1985-01-01

    Selected undergraduates (N=32) on the basis of Creative Imagination Scale scores and randomly assigned high and low suggestibility subjects to progressive relaxation (PR) and suggestions of relaxation (SR) training modes. Results revealed a significant pre-post relaxation effect, and main efffects for both suggestibility and training mode. (NRB)

  6. Pre-relaxation in weakly interacting models

    Science.gov (United States)

    Bertini, Bruno; Fagotti, Maurizio

    2015-07-01

    We consider time evolution in models close to integrable points with hidden symmetries that generate infinitely many local conservation laws that do not commute with one another. The system is expected to (locally) relax to a thermal ensemble if integrability is broken, or to a so-called generalised Gibbs ensemble if unbroken. In some circumstances expectation values exhibit quasi-stationary behaviour long before their typical relaxation time. For integrability-breaking perturbations, these are also called pre-thermalisation plateaux, and emerge e.g. in the strong coupling limit of the Bose-Hubbard model. As a result of the hidden symmetries, quasi-stationarity appears also in integrable models, for example in the Ising limit of the XXZ model. We investigate a weak coupling limit, identify a time window in which the effects of the perturbations become significant and solve the time evolution through a mean-field mapping. As an explicit example we study the XYZ spin-\\frac{1}{2} chain with additional perturbations that break integrability. One of the most intriguing results of the analysis is the appearance of persistent oscillatory behaviour. To unravel its origin, we study in detail a toy model: the transverse-field Ising chain with an additional nonlocal interaction proportional to the square of the transverse spin per unit length (2013 Phys. Rev. Lett. 111 197203). Despite being nonlocal, this belongs to a class of models that emerge as intermediate steps of the mean-field mapping and shares many dynamical properties with the weakly interacting models under consideration.

  7. Relaxed Poisson cure rate models.

    Science.gov (United States)

    Rodrigues, Josemar; Cordeiro, Gauss M; Cancho, Vicente G; Balakrishnan, N

    2016-03-01

    The purpose of this article is to make the standard promotion cure rate model (Yakovlev and Tsodikov, ) more flexible by assuming that the number of lesions or altered cells after a treatment follows a fractional Poisson distribution (Laskin, ). It is proved that the well-known Mittag-Leffler relaxation function (Berberan-Santos, ) is a simple way to obtain a new cure rate model that is a compromise between the promotion and geometric cure rate models allowing for superdispersion. So, the relaxed cure rate model developed here can be considered as a natural and less restrictive extension of the popular Poisson cure rate model at the cost of an additional parameter, but a competitor to negative-binomial cure rate models (Rodrigues et al., ). Some mathematical properties of a proper relaxed Poisson density are explored. A simulation study and an illustration of the proposed cure rate model from the Bayesian point of view are finally presented. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. Arresting relaxation in Pickering Emulsions

    Science.gov (United States)

    Atherton, Tim; Burke, Chris

    2015-03-01

    Pickering emulsions consist of droplets of one fluid dispersed in a host fluid and stabilized by colloidal particles absorbed at the fluid-fluid interface. Everyday materials such as crude oil and food products like salad dressing are examples of these materials. Particles can stabilize non spherical droplet shapes in these emulsions through the following sequence: first, an isolated droplet is deformed, e.g. by an electric field, increasing the surface area above the equilibrium value; additional particles are then adsorbed to the interface reducing the surface tension. The droplet is then allowed to relax toward a sphere. If more particles were adsorbed than can be accommodated by the surface area of the spherical ground state, relaxation of the droplet is arrested at some non-spherical shape. Because the energetic cost of removing adsorbed colloids exceeds the interfacial driving force, these configurations can remain stable over long timescales. In this presentation, we present a computational study of the ordering present in anisotropic droplets produced through the mechanism of arrested relaxation and discuss the interplay between the geometry of the droplet, the dynamical process that produced it, and the structure of the defects observed.

  9. Vibrational relaxation in OCS mixtures

    International Nuclear Information System (INIS)

    Simpson, C.J.S.M.; Gait, P.D.; Simmie, J.M.

    1976-01-01

    Experimental measurements are reported of vibrational relaxation times which may be used to show whether there is near resonant vibration-rotation energy transfer between OCS and H 2 , D 2 or HD. Vibrational relaxation times have been measured in OCS and OCS mixtures over the temperature range 360 to 1000 K using a shock tube and a laser schlieren system. The effectiveness of the additives in reducing the relaxation time of OCS is in the order 4 He 3 He 2 2 and HD. Along this series the effect of an increase in temperature changes from the case of speeding up the rate with 4 He to retarding it with D 2 , HD and H 2 . There is no measurable difference in the effectiveness of n-D 2 and o-D 2 and little, or no, difference between n-H 2 and p-H 2 . Thus the experimental results do not give clear evidence for rotational-vibration energy transfer between hydrogen and OCS. This contrasts with the situation for CO 2 + H 2 mixtures. (author)

  10. Relaxed plasma-vacuum systems

    International Nuclear Information System (INIS)

    Spies, G.O.; Lortz, D.; Kaiser, R.

    2001-01-01

    Taylor's theory of relaxed toroidal plasmas (states of lowest energy with fixed total magnetic helicity) is extended to include a vacuum between the plasma and the wall. In the extended variational problem, one prescribes, in addition to the helicity and the magnetic fluxes whose conservation follows from the perfect conductivity of the wall, the fluxes whose conservation follows from the assumption that the plasma-vacuum interface is also perfectly conducting (if the wall is a magnetic surface, then one has the toroidal and the poloidal flux in the vacuum). Vanishing of the first energy variation implies a pressureless free-boundary magnetohydrostatic equilibrium with a Beltrami magnetic field in the plasma, and in general with a surface current in the interface. Positivity of the second variation implies that the equilibrium is stable according to ideal magnetohydrodynamics, that it is a relaxed state according to Taylor's theory if the interface is replaced by a wall, and that the surface current is nonzero (at least if there are no closed magnetic field lines in the interface). The plane slab, with suitable boundary conditions to simulate a genuine torus, is investigated in detail. The relaxed state has the same double symmetry as the vessel if, and only if, the prescribed helicity is in an interval that depends on the prescribed fluxes. This interval is determined in the limit of a thin slab

  11. Regularized Label Relaxation Linear Regression.

    Science.gov (United States)

    Fang, Xiaozhao; Xu, Yong; Li, Xuelong; Lai, Zhihui; Wong, Wai Keung; Fang, Bingwu

    2018-04-01

    Linear regression (LR) and some of its variants have been widely used for classification problems. Most of these methods assume that during the learning phase, the training samples can be exactly transformed into a strict binary label matrix, which has too little freedom to fit the labels adequately. To address this problem, in this paper, we propose a novel regularized label relaxation LR method, which has the following notable characteristics. First, the proposed method relaxes the strict binary label matrix into a slack variable matrix by introducing a nonnegative label relaxation matrix into LR, which provides more freedom to fit the labels and simultaneously enlarges the margins between different classes as much as possible. Second, the proposed method constructs the class compactness graph based on manifold learning and uses it as the regularization item to avoid the problem of overfitting. The class compactness graph is used to ensure that the samples sharing the same labels can be kept close after they are transformed. Two different algorithms, which are, respectively, based on -norm and -norm loss functions are devised. These two algorithms have compact closed-form solutions in each iteration so that they are easily implemented. Extensive experiments show that these two algorithms outperform the state-of-the-art algorithms in terms of the classification accuracy and running time.

  12. Spin-lattice relaxation of individual solid-state spins

    Science.gov (United States)

    Norambuena, A.; Muñoz, E.; Dinani, H. T.; Jarmola, A.; Maletinsky, P.; Budker, D.; Maze, J. R.

    2018-03-01

    Understanding the effect of vibrations on the relaxation process of individual spins is crucial for implementing nanosystems for quantum information and quantum metrology applications. In this work, we present a theoretical microscopic model to describe the spin-lattice relaxation of individual electronic spins associated to negatively charged nitrogen-vacancy centers in diamond, although our results can be extended to other spin-boson systems. Starting from a general spin-lattice interaction Hamiltonian, we provide a detailed description and solution of the quantum master equation of an electronic spin-one system coupled to a phononic bath in thermal equilibrium. Special attention is given to the dynamics of one-phonon processes below 1 K where our results agree with recent experimental findings and analytically describe the temperature and magnetic-field scaling. At higher temperatures, linear and second-order terms in the interaction Hamiltonian are considered and the temperature scaling is discussed for acoustic and quasilocalized phonons when appropriate. Our results, in addition to confirming a T5 temperature dependence of the longitudinal relaxation rate at higher temperatures, in agreement with experimental observations, provide a theoretical background for modeling the spin-lattice relaxation at a wide range of temperatures where different temperature scalings might be expected.

  13. Relaxation path of metastable nanoclusters in oxide dispersion strengthened materials

    Energy Technology Data Exchange (ETDEWEB)

    Ribis, J., E-mail: joel.ribis@cea.fr [DEN-Service de Recherches Métallurgiques Appliquées, CEA, Université Paris-Saclay, F-91191, Gif-sur-Yvette (France); Thual, M.A. [LLB, CEA, CNRS, Université Paris-Saclay, CEA Saclay, 91191, Gif-sur-Yvette (France); Guilbert, T.; Carlan, Y. de [DEN-Service de Recherches Métallurgiques Appliquées, CEA, Université Paris-Saclay, F-91191, Gif-sur-Yvette (France); Legris, A. [UMET, CNRS/UMR 8207, Bât. C6, Univ. Lille 1, 59655 Villeneuve d’Ascq (France)

    2017-02-15

    ODS steels are a promising class of structural materials for sodium cooled fast reactor application. The ultra-high density of the strengthening nanoclusters dispersed within the ferritic matrix is responsible of the excellent creep properties of the alloy. Fine characterization of the nanoclusters has been conducted on a Fe-14Cr-0.3Ti-0.3Y{sub 2}O{sub 3} ODS material using High Resolution and Energy Filtered Transmission Electron Microscopy. The nanoclusters exhibit a cubic symmetry possibly identified as f.c.c and display a non-equilibrium YTiCrO chemical composition thought to be stabilized by a vacancy supersaturation. These nanoclusters undergo relaxation towards the Y{sub 2}Ti{sub 2}O{sub 7}-like state as they grow. A Cr shell is observed around the relaxed nano-oxides, this size-dependent shell may form after the release of Cr by the particles. The relaxation energy barrier appears to be higher for the smaller particles probably owing to a volume/surface ratio effect in reason to the full coherency of the nanoclusters. - Highlights: • The nanoclusters display a f.c.c. cubic symmetry and a non-equilibrium YTiCrO chemical composition. • During thermal annealing the coherent nanocluster transform into semi-coherent pyrochlore particles. • A Cr ring is observed around the relaxed pyrochlore type particles.

  14. [Development of an Analgesia Therapy System for Delivery Based on Bio-feedback Transcuataneous Electrical Nerve Stimulation].

    Science.gov (United States)

    Deng Songbo; Lu Yaosheng; Fang, Kun; Qin, Ruyi; Lin, Zhan

    2015-06-01

    Transcuataneous electrical nerve stimulation (TENS) analgesia as a non-drug method has received people's more and more attention recently. Considering problems of existing products, such as unstable performance and unsatisfied effectiveness, we developed a new analgesia therapy system for delivery based on bio-feedback TENS in our laboratory. We proposed a new idea for stimulation signal design, that is, we modulated a middle frequency signal by a traditional low frequency TENS wave in the new system. We designed different prescription waves for pain relief during a uterine contraction or massage between contractions. In the end, a bio-feedback TENS method was proposed, in which the waveforms of stimulation signals were selected and their parameters were modified automatically based on feedback from uterine pressure, etc. It was proved through quality tests and clinical trials that the system had good performance and satisfied analgesia effectiveness.

  15. Correlation of carrier localization with relaxation time distribution and electrical conductivity relaxation in silver-nanoparticle-embedded moderately doped polypyrrole nanostructures

    Science.gov (United States)

    Biswas, Swarup; Dutta, Bula; Bhattacharya, Subhratanu

    2014-02-01

    The electrical conductivity relaxation in moderately doped polypyrrole and its nanocomposites reinforced with different proportion of silver nanoparticles was investigated in both frequency and time domain. An analytical distribution function of relaxation times is constructed from the results obtained in the frequency domain formalism and is used to evaluate the Kohlrausch-Williams-Watts (KWW) type decay function in the time domain. The thermal evolution of different relaxation parameters was analyzed. The temperature-dependent dc electrical conductivity, estimated from the average conductivity relaxation time is observed to depend strongly on the nanoparticle loading and follows Mott three-dimensional variable range hopping (VRH) conduction mechanism. The extent of charge carrier localization calculated from the VRH mechanism is well correlated to the evidences obtained from the structural characterizations of different nanostructured samples.

  16. Capturing molecular multimode relaxation processes in excitable gases based on decomposition of acoustic relaxation spectra

    Science.gov (United States)

    Zhu, Ming; Liu, Tingting; Wang, Shu; Zhang, Kesheng

    2017-08-01

    Existing two-frequency reconstructive methods can only capture primary (single) molecular relaxation processes in excitable gases. In this paper, we present a reconstructive method based on the novel decomposition of frequency-dependent acoustic relaxation spectra to capture the entire molecular multimode relaxation process. This decomposition of acoustic relaxation spectra is developed from the frequency-dependent effective specific heat, indicating that a multi-relaxation process is the sum of the interior single-relaxation processes. Based on this decomposition, we can reconstruct the entire multi-relaxation process by capturing the relaxation times and relaxation strengths of N interior single-relaxation processes, using the measurements of acoustic absorption and sound speed at 2N frequencies. Experimental data for the gas mixtures CO2-N2 and CO2-O2 validate our decomposition and reconstruction approach.

  17. Sandpile model for relaxation in complex systems

    International Nuclear Information System (INIS)

    Vazquez, A.; Sotolongo-Costa, O.; Brouers, F.

    1997-10-01

    The relaxation in complex systems is, in general, nonexponential. After an initial rapid decay the system relaxes slowly following a long time tail. In the present paper a sandpile moderation of the relaxation in complex systems is analysed. Complexity is introduced by a process of avalanches in the Bethe lattice and a feedback mechanism which leads to slower decay with increasing time. In this way, some features of relaxation in complex systems: long time tails relaxation, aging, and fractal distribution of characteristic times, are obtained by simple computer simulations. (author)

  18. A brief review and clinical application of heart rate variability biofeedback in sports, exercise, and rehabilitation medicine.

    Science.gov (United States)

    Prinsloo, Gabriell E; Rauch, H G Laurie; Derman, Wayne E

    2014-05-01

    An important component of the effective management of chronic noncommunicable disease is the assessment and management of psychosocial stress. The measurement and modulation of heart rate variability (HRV) may be valuable in this regard. To describe the measurement and physiological control of HRV; to describe the impact of psychosocial stress on cardiovascular disease, metabolic syndrome, and chronic respiratory disease, and the relationship between these diseases and changes in HRV; and to describe the influence of biofeedback and exercise on HRV and the use of HRV biofeedback in the management of chronic disease. The PubMed, Medline, and Embase databases were searched (up to August 2013). Additional articles were obtained from the reference lists of relevant articles and reviews. Articles were individually selected for further review based on the quality and focus of the study, and the population studied. Heart rate variability is reduced in stress and in many chronic diseases, and may even predict the development and prognosis of some diseases. Heart rate variability can be increased with both exercise and biofeedback. Although the research on the effect of exercise is conflicting, there is evidence that aerobic training may increase HRV and cardiac vagal tone both in healthy individuals and in patients with disease. Heart rate variability biofeedback is also an effective method of increasing HRV and cardiac vagal tone, and has been shown to decrease stress and reduce the morbidity and mortality of disease. The assessment and management of psychosocial stress is a challenging but important component of effective comprehensive lifestyle interventions for the management of noncommunicable disease. It is, therefore, important for the sports and exercise physician to have an understanding of the therapeutic use of HRV modulation, both in the reduction of stress and in the management of chronic disease.

  19. Thermal Properties of Some Organic Liquids Using Ultrasonic Velocity Measurements

    Directory of Open Access Journals (Sweden)

    P. Ramadoss

    2011-01-01

    Full Text Available Debye temperature and thermal relaxation time has been calculated in normal and boiling temperature. Using thermal relaxation time, the heat of fusion has been calculated for nineteen organic liquids and the results throw light on the method of calculating heat of fusion.

  20. Development of stress relaxation measurement by a small size C-ring specimen method

    International Nuclear Information System (INIS)

    Shimanuki, Shizuka; Nakata, Kiyotomo; Kasahara, Shigeki; Kuniya, Jiro

    2002-01-01

    A stress relaxation measurement method has been developed by using C-ring specimens, and a specimen size effect has been evaluated taking radiation-induced stress relaxation into consideration. C-ring specimens were stressed by forcing a wedge in the gap. Giving an appropriate eccentric configuration in the half of the ring opposite the gap, the stress gradient along the circumference was eliminated in the section and the stress level could be varied by changing the gap spacing. The validity of the C-ring test method was confirmed by thermally stress relaxation experiments at annealing temperatures from 300 to 600degC for 1 min to 200 h in carbon steel: considerable stress relaxation could be measured for all levels of applied stress even at relatively low annealing temperatures. The relaxation results obtained from the C-ring test were in good agreement with those from a uniaxial tensile stress relaxation test. The smaller C-ring specimen with about 40 mm diameter, which is required for radiation-induced stress relaxation test, also showed adequate accuracy on stress relaxation at 600 to 830degC in stainless steel, compared with the large size C-ring specimen test. (author)

  1. The relationships between suggestibility, influenceability, and relaxability.

    Science.gov (United States)

    Polczyk, Romuald; Frey, Olga; Szpitalak, Malwina

    2013-01-01

    This research explores the relationships between relaxability and various aspects of suggestibility and influenceability. The Jacobson Progressive Muscle Relaxation procedure was used to induce relaxation. Tests of direct suggestibility, relating to the susceptibility of overt suggestions, and indirect suggestibility, referring to indirect hidden influence, as well as self-description questionnaires on suggestibility and the tendency to comply were used. Thayer's Activation-Deactivation Adjective Check List, measuring various kinds of activation and used as a pre- and posttest, determined the efficacy of the relaxation procedure. Indirect, direct, and self-measured suggestibility proved to be positively related to the ability to relax, measured by Thayer's subscales relating to emotions. Compliance was not related to relaxability. The results are discussed in terms of the aspects of relaxation training connected with suggestibility.

  2. Compaction and relaxation of biofilms

    KAUST Repository

    Valladares Linares, R.

    2015-06-18

    Operation of membrane systems for water treatment can be seriously hampered by biofouling. A better characterization of biofilms in membrane systems and their impact on membrane performance may help to develop effective biofouling control strategies. The objective of this study was to determine the occurrence, extent and timescale of biofilm compaction and relaxation (decompaction), caused by permeate flux variations. The impact of permeate flux changes on biofilm thickness, structure and stiffness was investigated in situ and non-destructively with optical coherence tomography using membrane fouling monitors operated at a constant crossflow velocity of 0.1 m s−1 with permeate production. The permeate flux was varied sequentially from 20 to 60 and back to 20 L m−2 h−1. The study showed that the average biofilm thickness on the membrane decreased after elevating the permeate flux from 20 to 60 L m−2 h−1 while the biofilm thickness increased again after restoring the original flux of 20 L m−2 h−1, indicating the occurrence of biofilm compaction and relaxation. Within a few seconds after the flux change, the biofilm thickness was changed and stabilized, biofilm compaction occurred faster than the relaxation after restoring the original permeate flux. The initial biofilm parameters were not fully reinstated: the biofilm thickness was reduced by 21%, biofilm stiffness had increased and the hydraulic biofilm resistance was elevated by 16%. Biofilm thickness was related to the hydraulic biofilm resistance. Membrane performance losses are related to the biofilm thickness, density and morphology, which are influenced by (variations in) hydraulic conditions. A (temporarily) permeate flux increase caused biofilm compaction, together with membrane performance losses. The impact of biofilms on membrane performance can be influenced (increased and reduced) by operational parameters. The article shows that a (temporary) pressure increase leads to more

  3. Experimental evidence for simultaneous relaxation processes in super spin glass γ-Fe2O3 nanoparticle system

    Science.gov (United States)

    Nikolic, V.; Perovic, M.; Kusigerski, V.; Boskovic, M.; Mrakovic, A.; Blanusa, J.; Spasojevic, V.

    2015-03-01

    Spherical γ-Fe2O3 nanoparticles with the narrow size distribution of (5 ± 1) nm were synthesized by the method of thermal decomposition from iron acetyl acetonate precursor. The existence of super spin-glass state at low temperatures and in low applied magnetic fields was confirmed by DC magnetization measurements on a SQUID magnetometer. The comprehensive investigation of magnetic relaxation dynamics in low-temperature region was conducted through the measurements of single-stop and multiple stop ZFC memory effects, ZFC magnetization relaxation, and AC susceptibility measurements. The experimental findings revealed the peculiar change of magnetic relaxation dynamics at T ≈ 10 K, which arose as a consequence of simultaneous existence of different relaxation processes in Fe2O3 nanoparticle system. Complementarity of the applied measurements was utilized in order to single out distinct relaxation processes as well as to elucidate complex relaxation mechanisms in the investigated interacting nanoparticle system.

  4. Phonon-impurity relaxation and acoustic wave absorption in yttrium-aluminium garnet crystals with impurities

    International Nuclear Information System (INIS)

    Ivanov, S.N.; Kotelyanskij, I.M.; Medved', V.V.

    1983-01-01

    The experimental results of investigations of the influence of substitution impurities in the yttrium-aluminium garnet lattice on absorption of high-frequency acoustic waves are presented. It is shown that the phonon-impurity relaxation processses affect at most the wave absorption and have resonance character when the acoustic wave interacts with the thermal phonon group in the vicinity of the perturbed part of the phonon spectrum caused by the impurity. The differences of time values between inelastic and elastic thermal phonons relaxations determined from the data on longitudinal and shear waves in pure and impurity garnet crystals are discussed

  5. Ultrasonic relaxations in borate glasses

    International Nuclear Information System (INIS)

    D'Angelo, G.; Tripodo, G.; Carini, G.; Cosio, E.; Bartolotta, A.; Di Marco, G.

    2004-01-01

    The attenuation and velocity of ultrasonic waves of frequencies in the range from 10 to 70 MHz have been measured in M 2 O-B 2 O 3 borate glasses (M: Li or Ag) as a function of temperature between 15 and 350 K. The velocity of sound waves decreases with increasing temperature in all the glasses, the decrease as the temperature is increased is larger in glasses containing silver than in those with lithium. A broad relaxation peak characterises the attenuation behaviour of the lithium and silver borate glasses at temperatures below 100 K and is paralleled by a corresponding dispersive behaviour of the sound velocity. Above 100 K, the ultrasonic velocity shows a nearly linear behaviour regulated by the vibrational anharmonicity, which decreases with increasing content of modifier oxide and is smaller in lithium than in silver borates. These results suggest that the relaxation of structural defects and the anharmonicity of borate glasses are strongly affected by two parameters: the number of bridging bonds per network forming ion and the polarising power of network modifier ions which occupy sites in the existing interstices

  6. Statistical mechanics of violent relaxation

    International Nuclear Information System (INIS)

    Shu, F.H.

    1978-01-01

    We reexamine the foundations of Lynden-Bell's statistical mechanical discussion of violent relaxation in collisionless stellar systems. We argue that Lynden-Bell's formulation in terms of a continuum description introduces unnecessary complications, and we consider a more conventional formulation in terms of particles. We then find the exclusion principle discovered by Lynden-Bell to be quantitatively important only at phase densities where two-body encounters are no longer negligible. Since the edynamical basis for the exclusion principle vanishes in such cases anyway, Lynden-Bell statistics always reduces in practice to Maxwell-Boltzmann statistics when applied to stellar systems. Lynden-Bell also found the equilibrium distribution function generally to be a sum of Maxwellians with velocity dispersions dependent on the phase density at star formation. We show that this difficulty vanishes in the particulate description for an encounterless stellar system as long as stars of different masses are initially well mixed in phase space. Our methods also demonstrate the equivalence between Gibbs's formalism which uses the microcanonical ensemble and Boltzmann's formalism which uses a coarse-grained continuum description. In addition, we clarify the concept of irreversible behavior on a macroscopic scale for an encounterless stellar system. Finally, we comment on the use of unusual macroscopic constraints to simulate the effects of incomplete relaxation

  7. EFFECTIVENESS OF BIOFEEDBACK IN THE CLOSED LOOP OF HEART RATE VARIABILITY AND PACED BREATHING IN THE PATIENTS WITH SOMATOFORM AUTONOMIC DYSFUNCTION

    Directory of Open Access Journals (Sweden)

    K. E. Morozova

    2014-06-01

    Full Text Available To study the effectiveness of biofeedback (BFB in the closed loop of heart rate variability (HRV and paced breathing in patients with somatoform autonomic dysfunction (SAD 20 patients with SAD (14 women and 6 men, mean age 19,53 ± 1,55 were examined. All probationers were divided into two groups comparable for sex and age: 1 – BFB group (15 patients, in which 7 sessions was held and 2 – the comparison group (5 patients, where only two sessions were completed -at the first and seventh day of the study. Additionally, all patients in both groups received diet food (Table № 10 by Pevzner, mebicar, glycine, tiotriazolin. Effectiveness of biofeedback was evaluated by comparing of parameters optimality (O, sensitivity (S, the efficiency (E and the integral index BQI in both groups. It was determined that biofeedback in the closed loop of HRV and paced breathing allows to optimize the state of the regulatory systems of the body in patients with SAD, moreover the combination of biofeedback sessions in the test loop and medical treatment are significantly better than isolated pharmacological therapy. High effectiveness of biofeedback in closed loop of HRV and paced breathing in patients with SAD allows us to recommend it as independent method of treatment, and as a component of combined therapy of this disease.

  8. Reduced heart rate variability in chronic severe traumatic brain injury: Association with impaired emotional and social functioning, and potential for treatment using biofeedback.

    Science.gov (United States)

    Francis, Heather M; Fisher, Alana; Rushby, Jacqueline A; McDonald, Skye

    2016-01-01

    Heart rate variability (HRV) may provide an index of capacity for social functioning and may be remediated by HRV biofeedback. Given reductions in HRV are found following traumatic brain injury (TBI), the present study aimed to determine whether lower HRV in TBI is associated with social function, and whether HRV biofeedback might be a useful remediation technique in this population. Resting state HRV and measures of social and emotional processing were collected in 30 individuals with severe TBI (3-34 years post-injury) and 30 controls. This was followed by a single session of HRV biofeedback. HRV was positively associated with social cognition and empathy, and negatively associated with alexithymia for the TBI group. Both TBI and control groups showed significantly increased HRV on both time-domain (i.e., SDNN, rMSSD) and frequency-domain measures (LF, HF, LF:HF ratio) during biofeedback compared to baseline. These results suggest that decreased HRV is linked to social and emotional function following severe TBI, and may be a novel target for therapy using HRV biofeedback techniques.

  9. Combination therapy with biofeedback, loperamide, and stool-bulking agents is effective for the treatment of fecal incontinence in women - a randomized controlled trial.

    Science.gov (United States)

    Sjödahl, Jenny; Walter, Susanna A; Johansson, Elin; Ingemansson, Anna; Ryn, Ann-Katrine; Hallböök, Olof

    2015-08-01

    Biofeedback and medical treatments have been extensively used for moderate fecal incontinence (FI). There is limited data comparing and combining these two treatments. The objective of this study was to evaluate the effect of biofeedback and medical treatments, separately and in combination. Sixty-four consecutive female patients, referred to a tertiary centre for FI, were included. The patients were randomized to start with either biofeedback (4-6 months) or medical treatment with loperamide and stool-bulking agents (2 months). Both groups continued with a combination of treatments, i.e. medical treatment was added to biofeedback and vice versa. A two-week prospective bowel symptom diary and anorectal physiology were evaluated at baseline, after single- and combination treatments. Fifty-seven patients completed the study. Median number of leakage episodes during two weeks decreased from 6 to 3 (p biofeedback and medical treatment is effective for symptom relief in FI. The symptom improvement was associated with improved fecal consistency, reduced urgency, and increased rectal sensory thresholds.

  10. Paramagnetic relaxation effects in perturbed angular correlations for arbitrary electronic relaxation time

    International Nuclear Information System (INIS)

    Chopin, C.; Spanjaard, D.; Hartmann-Boutron, F.

    1975-01-01

    Previous perturbation treatments of paramagnetic relaxation effects in γγ PAC were limited to the case of very short electronic relaxation times. This limitation is circumvented by invoking a new perturbation theory recently elaborated by Hirst and others for handling relaxation effects in Moessbauer spectra. Under the assumption of spherical electronic relaxation the perturbation factors are computed as functions of certain relaxation parameters which are directly related to the microscopic relaxation Hamiltonian. The results are compared to those of the stochastic theory of Scherer and Blume [fr

  11. An increased rectal maximum tolerable volume and long anal canal are associated with poor short-term response to biofeedback therapy for patients with anismus with decreased bowel frequency and normal colonic transit time.

    Science.gov (United States)

    Rhee, P L; Choi, M S; Kim, Y H; Son, H J; Kim, J J; Koh, K C; Paik, S W; Rhee, J C; Choi, K W

    2000-10-01

    Biofeedback is an effective therapy for a majority of patients with anismus. However, a significant proportion of patients still failed to respond to biofeedback, and little has been known about the factors that predict response to biofeedback. We evaluated the factors associated with poor response to biofeedback. Biofeedback therapy was offered to 45 patients with anismus with decreased bowel frequency (less than three times per week) and normal colonic transit time. Any differences in demographics, symptoms, and parameters of anorectal physiologic tests were sought between responders (in whom bowel frequency increased up to three times or more per week after biofeedback) and nonresponders (in whom bowel frequency remained less than three times per week). Thirty-one patients (68.9 percent) responded to biofeedback and 14 patients (31.1 percent) did not. Anal canal length was longer in nonresponders than in responders (4.53 +/- 0.5 vs. 4.08 +/- 0.56 cm; P = 0.02), and rectal maximum tolerable volume was larger in nonresponders than in responders. (361 +/- 87 vs. 302 +/- 69 ml; P = 0.02). Anal canal length and rectal maximum tolerable volume showed significant differences between responders and nonresponders on multivariate analysis (P = 0.027 and P = 0.034, respectively). This study showed that a long anal canal and increased rectal maximum tolerable volume are associated with poor short-term response to biofeedback for patients with anismus with decreased bowel frequency and normal colonic transit time.

  12. Cross relaxation in nitroxide spin labels

    DEFF Research Database (Denmark)

    Marsh, Derek

    2016-01-01

    Cross relaxation, and mI-dependence of the intrinsic electron spin-lattice relaxation rate We, are incorporated explicitly into the rate equations for the electron-spin population differences that govern the saturation behaviour of 14N- and 15N-nitroxide spin labels. Both prove important in spin......-label EPR and ELDOR, particularly for saturation recovery studies. Neither for saturation recovery, nor for CW-saturation EPR and CW-ELDOR, can cross relaxation be described simply by increasing the value of We, the intrinsic spin-lattice relaxation rate. Independence of the saturation recovery rates from...... the hyperfine line pumped or observed follows directly from solution of the rate equations including cross relaxation, even when the intrinsic spin-lattice relaxation rate We is mI-dependent....

  13. Structural relaxation in annealed hyperquenched basaltic glasses

    DEFF Research Database (Denmark)

    Guo, Xiaoju; Mauro, John C.; Potuzak, M.

    2012-01-01

    The enthalpy relaxation behavior of hyperquenched (HQ) and annealed hyperquenched (AHQ) basaltic glass is investigated through calorimetric measurements. The results reveal a common onset temperature of the glass transition for all the HQ and AHQ glasses under study, indicating that the primary...... relaxation is activated at the same temperature regardless of the initial departure from equilibrium. The analysis of secondary relaxation at different annealing temperatures provides insights into the enthalpy recovery of HQ glasses....

  14. ENERGY RELAXATION OF HELIUM ATOMS IN ASTROPHYSICAL GASES

    International Nuclear Information System (INIS)

    Lewkow, N. R.; Kharchenko, V.; Zhang, P.

    2012-01-01

    We report accurate parameters describing energy relaxation of He atoms in atomic gases, important for astrophysics and atmospheric science. Collisional energy exchange between helium atoms and atomic constituents of the interstellar gas, heliosphere, and upper planetary atmosphere has been investigated. Energy transfer rates, number of collisions required for thermalization, energy distributions of recoil atoms, and other major parameters of energy relaxation for fast He atoms in thermal H, He, and O gases have been computed in a broad interval of energies from 10 meV to 10 keV. This energy interval is important for astrophysical applications involving the energy deposition of energetic atoms and ions into atmospheres of planets and exoplanets, atmospheric evolution, and analysis of non-equilibrium processes in the interstellar gas and heliosphere. Angular- and energy-dependent cross sections, required for an accurate description of the momentum-energy transfer, are obtained using ab initio interaction potentials and quantum mechanical calculations for scattering processes. Calculation methods used include partial wave analysis for collisional energies below 2 keV and the eikonal approximation at energies higher than 100 eV, keeping a significant energy region of overlap, 0.1-2 keV, between these two methods for their mutual verification. The partial wave method and the eikonal approximation excellently match results obtained with each other as well as experimental data, providing reliable cross sections in the astrophysically important interval of energies from 10 meV to 10 keV. Analytical formulae, interpolating obtained energy- and angular-dependent cross sections, are presented to simplify potential applications of the reported database. Thermalization of fast He atoms in the interstellar gas and energy relaxation of hot He and O atoms in the upper atmosphere of Mars are considered as illustrative examples of potential applications of the new database.

  15. Dielectric Relaxation of Water: Theory and Experiment

    International Nuclear Information System (INIS)

    Adhikari, Narayan Prasad; Paudyal, Harihar; Johri, Manoj

    2010-06-01

    We have studied the hydrogen bond dynamics and methods for evaluation of probability and relaxation time for hydrogen bond network. Further, dielectric relaxation time has been calculated by using a diagonalization procedure by obtaining eigen values (inverse of relaxation time) of a master equation framed on the basis of Fokker-Planck equations. Microwave cavity spectrometer has been described to make measurements of relaxation time. Slater's perturbation equations are given for the analysis of the data. A comparison of theoretical and experimental data shows that there is a need for improvements in the theoretical model and experimental techniques to provide exact information about structural properties of water. (author)

  16. Game Design to Measure Reflexes and Attention Based on Biofeedback Multi-Sensor Interaction

    Directory of Open Access Journals (Sweden)

    Inigo de Loyola Ortiz-Vigon Uriarte

    2015-03-01

    Full Text Available This paper presents a multi-sensor system for implementing biofeedback as a human-computer interaction technique in a game involving driving cars in risky situations. The sensors used are: Eye Tracker, Kinect, pulsometer, respirometer, electromiography (EMG and galvanic skin resistance (GSR. An algorithm has been designed which gives rise to an interaction logic with the game according to the set of physiological constants obtained from the sensors. The results reflect a 72.333 response to the System Usability Scale (SUS, a significant difference of p = 0.026 in GSR values in terms of the difference between the start and end of the game, and an r = 0.659 and p = 0.008 correlation while playing with the Kinect between the breathing level and the energy and joy factor. All the sensors used had an impact on the end results, whereby none of them should be disregarded in future lines of research, even though it would be interesting to obtain separate breathing values from that of the cardio.

  17. Efectividad del biofeedback electromiográfico en la rehabilitación de lesiones deportivas

    Directory of Open Access Journals (Sweden)

    Antonio Hern\\u00E1ndez-Mendo

    2014-01-01

    Full Text Available La utilización del biofeedback electromiográfico (BF-EMG en la rehabilitación de lesiones está sobradamente referenciada en la literatura psicológica. A pesar de los trabajos pioneros en la década de los años ochenta, en el ámbito deportivo, apenas ha transcendido su utilización en la rehabilitación de lesiones deportivas. Se presenta un estudio de doce casos de futbolistas profesionales de la liga española agrupados en dos tipos de patologías distintas (fracturas en los miembros superiores y lesiones de rodilla que han sido sometidos a un tratamiento de BF-EMG, paralelo al plan de rehabilitación establecido por los servicios médicos de cada club. Se utiliza un diseño ABA. En cada sesión se registra una línea pre y post que permite determinar la ganancia EMG adquirida en cada punto de la sesión. La intervención se da por finalizada cuando el futbolista alcanza de forma estable el criterio establecido por el miembro hemilateral. En todos los casos se realiza una sesión más de seguimiento. Todos los casos presentan mejorías notorias y estables. Los resultados globales permiten considerar que el BF-EMG es eficaz en estas patologías.

  18. Professional issues in the use of diagnostic ultrasound biofeedback in physiotherapy of the female pelvic floor

    International Nuclear Information System (INIS)

    McKiernan, Sharmaine; Chiarelli, Pauline; Warren-Forward, Helen

    2013-01-01

    The usage of diagnostic ultrasound equipment has expanded into physiotherapy. The aim of this paper is to deliver to both the ultrasound and physiotherapy professions an understanding of the use of diagnostic ultrasound for biofeedback in physiotherapy of the female pelvic floor and the issues related to competent and safe practice, including accessing suitable training. This has been evaluated using a qualitative research paradigm with data gathered via focus groups of Australian physiotherapists. The target group were pelvic floor physiotherapists as this is one of the main uses of diagnostic ultrasound within physiotherapy and the main area physiotherapists would like to be trained in. Two focus groups were run with a total of sixteen physiotherapists. Focus group participants reported their training in diagnostic ultrasound to be largely self directed. They also reported they were learning on their patients. Despite very limited training, participants demonstrated some familiarity with images and equipment settings. Participants felt the modality had a role within physiotherapy as an adjunct to their current practices. The main need raised by participants during the focus groups was related to patient expectations and the fact that the physiotherapist may miss evidence of pathology

  19. HRV biofeedback for pediatric irritable bowel syndrome and functional abdominal pain: a clinical replication series.

    Science.gov (United States)

    Stern, Mark J; Guiles, Robert A F; Gevirtz, Richard

    2014-12-01

    Irritable bowel syndrome (IBS) and Functional Abdominal Pain (FAP) are among the most commonly reported Functional Gastrointestinal Disorders. Both have been associated with varying autonomic dysregulation. Heart Rate Variability Biofeedback (HRVB) has recently begun to show efficacy in the treatment of both IBS and FAP. The purpose of this multiple clinical replication series was to analyze the clinical outcomes of utilizing HRVB in a clinical setting. Archival data of twenty-seven consecutive pediatric outpatients diagnosed with IBS or FAP who received HRVB were analyzed. Clinical outcomes were self-report and categorized as full or remission with patient satisfaction, or no improvement. Qualitative reports of patient experiences were also noted. Full remission was achieved by 69.2 % and partial remission was achieved by 30.8 % of IBS patients. Full remission was achieved by 63.6 % and partial remission was achieved by 36.4 % of FAP patients. No patients in either group did not improve to a level of patient satisfaction or >50 %. Patient's commonly reported feeling validated in their discomfort as a result of psychophysiological education. Results suggest that HRVB is a promising intervention for pediatric outpatients with IBS or FAP. Randomized controlled trials are necessary to accurately determine clinical efficacy of HRVB in the treatment of IBS and FAP.

  20. Chronic prostatitis presenting with dysfunctional voiding and effects of pelvic floor biofeedback treatment.

    Science.gov (United States)

    He, Wei; Chen, Minfeng; Zu, Xiongbing; Li, Yuan; Ning, Keping; Qi, Lin

    2010-04-01

    To investigate the features of chronic prostatitis presenting with dysfunctional voiding (DV) and the effects of pelvic floor biofeedback (PFB). The study included 21 patients, diagnosed by having symptoms for > or =3 months, including urinary frequency and urgency, voiding difficulty, upper abdominal or perineal discomfort, and with a score of > or =1 on the first and second part of the National Institutes of Health Chronic Prostatitis Symptom Index (NIH-CPSI). Patients with bacterial prostatitis, urethritis, interstitial cystitis, urethral stricture and neurogenic bladder were excluded. All patients had a urodynamic examination, to assess the uroflow curve, maximum urinary flow rate (Q(max)), maximum detrusor pressure during the storage phase (P(det.max)), maximum urethral pressure (MUP) and the maximum urethral closure pressure (MUCP) were recorded. PFB was carried out in patients with non-neurogenic detrusor sphincter dyssynergia, and the effects evaluated after 10 weeks. Before and after PFB treatment the mean (sd) Q(max), P(det.max), MUP, MUCP were 8.2 (4.1) vs 15.1 (7.3) mL/s, 125.1 (75.3) vs 86.3 (54.2) cmH(2)O, 124.3 (23.3) vs 65.4 (23.0) cmH(2)O and 101.5 (43.6) vs 43.5 (16.7) cmH(2)O, all significantly different (P PFB had satisfactory short-term effects on these patients.