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Sample records for vibroacoustic stimulation vas

  1. Fetal heart rate after vibroacoustic stimulation.

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    Hoh, Jeong Kyu; Park, Young-Sun; Cha, Kyung-Joon; Park, Moon-Il

    2009-07-01

    To define reference ranges for fetal heart rate (FHR) parameters after vibroacoustic stimulation (VAS) according to gestational age by determining the relationship between FHR and gestational age using a computerized analysis system. Data were analyzed from 3453 women using 10-minute observational recordings during nonstress testing (NST) and VAS testing. FHR parameters were analyzed according to gestational age. All FHR parameters were related to gestational age except for mean baseline FHR, which did not vary significantly with gestational age. All other parameters followed trends similar to the NST results, except for decelerations. FHR parameters after VAS differed significantly according to gestational age. The results suggest that the gestational age of the fetus should be considered when interpreting FHR patterns after VAS.

  2. Vibroacoustic stimulation in normal term human pregnancy.

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    D'Elia, A; Pighetti, M; Vanacore, F; Fabbrocini, G; Arpaia, L

    2005-05-01

    To examine the effects of vibroacoustic stimulation (VAS) on fetal heart rate (FHR) in term human fetuses by computerized carditocography system. FHR was analyzed 20 min before and 30 min after vibroacoustic stimulation using the Oxford Sonicaid System 8002 for computerized FHR measurement. Recordings were made in 31 uncomplicated pregnancies at 36-42 weeks' gestation. Vibroacustic stimulation of the fetus evoked a significant increase in all the parameters evaluated (number of fetal movements, of accelerations above 10 and 15 bpm, in high- and low-variability episodes, and in short-term variations). Concerning the effect of behavioural states on the response to VAS, some changes (FHR, high-variability episodes) occurred independently of behavioural states, while other parameters (accelerations >10 and 15 bpm: short-term variation) underwent statistically significant changes only for behavioural states 1F and 2F. Our study supports the hypothesis of a significant fetal response in normal term pregnancy, as clearly shown by computerized cardiotocography. The immediate response occurred independently of behavioural states, although some differences were present (mainly for F1 and F2 states) if the evaluation was extended in time.

  3. Fetal tachyarrhythmia associated with vibroacoustic stimulation.

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    Laventhal, Naomi T; Dildy, Gary A; Belfort, Michael A

    2003-05-01

    Vibroacoustic stimulation is commonly used in antepartum fetal testing and has known benefits. Although the procedure has been deemed safe, questions have been raised as to potentially adverse effects, and the adult cardiology literature identifies a link between abrupt sound stimulation and severe tachyarrhythmias. A fetus with premature atrial contractions converted to supraventricular tachycardia immediately after vibroacoustic stimulation. The tachyarrhythmia spontaneously reverted to baseline after 4 minutes. The infant was treated for junctional reentry tachycardia at birth. Although the cardiac effects of vibroacoustic stimulation have previously been characterized as benign, the use of this modality may warrant restriction in the setting of known fetal arrhythmias.

  4. Technical note: simple vibroacoustic foetal stimulator.

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    Stojanović, D; Frković, A; Filiplić-Stojanović, H; Kirincić, N

    2001-01-01

    To build and test a simple vibroacoustic foetal stimulator. A vibroacoustic foetal stimulator was constructed and subjected to bench testing. Clinical trial was carried out in comparison to an electro laynx. Screening specificity of 98% and 100% sensitivity was achieved, with no decrease in specificity due to user's maladjustments. The device was characterized by simple use, maintenance and disinfection. The device is a good screening instrument for foetal health in prenatal care, despite its simplicity and low price.

  5. Is intrapartum vibroacoustic stimulation an effective predictor of fetal acidosis?

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    Lin, C C; Vassallo, B; Mittendorf, R

    2001-01-01

    The hypothesis of this prospective study is that intrapartum vibroacoustic stimulation (VAS) is an effective predictor of fetal acidosis during labor. Various clinical conditions, such as term versus preterm gestation, first stage versus second stage of labor, and fetal heart rate (FHR) variable decelerations versus late decelerations will be tested. During the study period, 113 patients were studied prospectively in either active phase of first stage (n = 53) or during the second stage of labor (n = 60). They were selected from cases exhibiting moderate to severe FHR variable decelerations or late decelerations. The fetuses of study subjects received a VAS for three seconds and FHR changes were recorded. Fetal scalp blood pH or umbilical arterial blood pH was obtained within 15 minutes of VAS. The relationship between FHR responses to VAS and fetal blood pH in term and preterm gestations, the relationship of two tests (VAS and fetal blood pH) to type of FHR decelerations, and the predictability of neonatal morbidity by two tests were analyzed. Where appropriate, Fisher's exact test (p or = 7.20, and between a negative response to VAS (no acceleration or decelerations) and pH or = 37 weeks) and preterm ( or = 34 weeks) fetuses. Since the preterm fetuses enrolled in the study were limited in number, it is difficult to draw adequate conclusions. The positive predictive value (PPV) of fetal acidosis was 67% in both groups of FHR variable decelerations and late decelerations, but the false negative rate of acceleration VAS response for predicting no acidosis was significantly higher in the group of late decelerations (29% vs 8%, p = 0.034). Finally, both a negative VAS response and fetal acidosis (pH < 7.20) have equal predictability for neonatal morbidity. The PPV of NICU admission by a negative VAS response was two times higher than that of fetal acidosis (PPV = 61% vs 29%, p = 0.038). We found that intrapartum VAS was an effective predictor of fetal acidosis in

  6. The conformity of BPP and vibroacoustic stimulation results in fetal non reactive non stress test

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    M. Modarres

    2006-08-01

    Full Text Available Background: The most frequently used test for evaluation of fetal health is the Non Stress Test (NST. Unfortunately it has a high incidence of false positive results. The combination of vibroacoustic stimulation with the NTS has been shown to reduce non reactive results. Methods: A tests assessment method was chosen with a simple randomized sampling. 40 pregnant women with non reactive NST in the first 20 minutes who received VAS in one of Tehran University's Hospitals were compared with BPP scores. A vibroacoustic stimulation was applied for a 3 seconds on the maternal abdomen and fallowed within 10 minutes.Data collection tools were NST, sonography instruments ,NST result paper, tooth brusher, watch, demographic questioner and check list. Data analysis was made by descriptive static and by using the Fisher's Exact Test (with level of significant at p<0/05. All statistical analysis were performed using an spss/win. Results: After VAS, 70% of non reactive tracing became reactive. All cases with fetal reactivity response after a VAS had a subsequent BPP score of 8 (negative predictive value of 100%. False positivity of VAS was lower than NST. Conclusion: VAS offers benefits, by decreasing the incidence of non reactive test and reducing test time. VAS lowers the rate of false positive NST. VAS is safe and allows more efficient of prenatal services. This test could be used as a rapid antepartum test to predict fetal well-being.

  7. Fetal vibroacoustic stimulation for facilitation of tests of fetal wellbeing.

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    Tan, Kelvin H; Smyth, Rebecca M D; Wei, Xing

    2013-12-07

    Acoustic stimulation of the fetus has been suggested to improve the efficiency of antepartum fetal heart rate testing. To assess the advantages and disadvantages of the use of fetal vibroacoustic stimulation in conjunction with tests of fetal wellbeing. We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (30 September 2013). All published and unpublished randomised controlled trials assessing the merits of the use of fetal vibroacoustic stimulation in conjunction with tests of fetal wellbeing. All review authors independently extracted data and assessed trial quality. Authors of published and unpublished trials were contacted for further information. Altogether 12 trials with a total of 6822 participants were included. Fetal vibroacoustic stimulation reduced the incidence of non-reactive antenatal cardiotocography test (nine trials; average risk ratio (RR) 0.62, 95% confidence interval (CI) 0.48 to 0.81). Vibroacoustic stimulation compared with mock stimulation evoked significantly more fetal movements when used in conjunction with fetal heart rate testing (one trial, RR 0.23, 95% CI 0.18 to 0.29). Vibroacoustic stimulation offers benefits by decreasing the incidence of non-reactive cardiotocography and reducing the testing time. Further randomised trials should be encouraged to determine not only the optimum intensity, frequency, duration and position of the vibroacoustic stimulation, but also to evaluate the efficacy, predictive reliability, safety and perinatal outcome of these stimuli with cardiotocography and other tests of fetal wellbeing.

  8. Effect of maternal stress on fetal heart rate assessed by vibroacoustic stimulation.

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    Makino, I; Matsuda, Y; Yoneyama, M; Hirasawa, K; Takagi, K; Ohta, H; Konishi, Y

    2009-01-01

    This study was designed to determine whether maternal stress levels, state and trait anxiety levels, and stress hormones affect fetal heart rate (FHR) patterns after vibroacoustic stimulation (VAS) at 30 weeks of gestation. A total of 24 healthy pregnant women with a single fetus pregnancy were enrolled. Corticotropin releasing hormone (CRH) and adrenocorticotropic hormone in maternal plasma and cortisol, and chromogranin A in saliva were measured. The FHR patterns after VAS were divided into three types: type I, a long period of acceleration or one acceleration lasting > 1 min or at least two accelerations lasting > 15 s; type II, a biphasic response with acceleration followed by deceleration; and type III, no response or prolonged deceleration. In the high trait anxiety group, CRH levels were significantly higher than in the low trait anxiety group, and FHR patterns after VAS showed mostly a type II response pattern. These findings suggest that stress in pregnant women with high trait anxiety may influence FHR patterns after VAS.

  9. Maturation of Human Fetal Responses to Vibroacoustic Stimulation.

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    Kisilevsky, Barbara S.; And Others

    1992-01-01

    Fetuses received vibroacoustic stimulation while movement and heart rate were monitored. From 29 weeks, at least 83 percent of fetuses responded to stimulation with heart rate acceleration. Between 26 and 36 weeks, the percentage of fetuses responding to stimulation with movement increased from 58 to 100 percent. (BC)

  10. Responses to vibroacoustic stimulation in a fetus with an encephalocele compared to responses of normal fetuses.

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    van Heteren, C F; Boekkooi, P F; Jongsma, H W; Nijhuis, J G

    2000-01-01

    Observation of fetal movement and fetal heart rate (FHR) responses to repeated vibroacoustic stimulation (VAS) might be useful as a measure to assess fetal well-being and to assess the integrity of the fetal central nervous system (CNS). We observed the movement and FHR responses to repeated VAS of a term fetus with a serious brain anomaly as compared to responses of normal term fetuses. In 37 normal term fetuses and in a term fetus with an encephalocele we studied movement and FHR response to repeated VAS. All normal fetuses responded within 1 s after stimulation with general body movement and FHR acceleration. At 36 gestational weeks, no movement or FHR responses were seen in the fetus with an encephalocele. Repetition of the test in this fetus after one week still showed no response to repeated VAS. Normal fetuses showed movement and FHR responses to external stimulation. The fetus with an encephalocele did not respond to repeated VAS with a movement or FHR acceleration. Case studies in fetuses with structural anomalies of the CNS are needed to gain insight into the spectrum of possible responses to VAS.

  11. Can vibroacoustic stimulation improve the efficiency of a tertiary care antenatal testing unit?

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    Turitz, Amy L; Bastek, Jamie A; Sammel, Mary D; Parry, Samuel; Schwartz, Nadav

    2012-12-01

    Our primary objective was to determine whether vibroacoustic stimulation (VAS) decreases time to fetal reactivity in the antenatal testing unit (ATU) of a tertiary care center. We performed a prospective, quality assurance initiative to determine whether VAS could increase the efficiency of our ATU. On pre-specified "VAS days," VAS was applied for 3 s, if the non-stress test was non-reactive in the first 10 min. Generalized estimating equations models were used to account for within subject correlation due to multiple appointments per patient. VAS use was associated with a 3.76-min reduction in time to reactivity (21.79 vs 25.55, p = 0.011) and a 56% reduction in the need for a biophysical profile (OR: 0.44, 95% CI: 0.21-0.90). Overall, however, we found no significant decrease in time spent on the monitor or in the ATU. Compliance with a strict VAS protocol may improve the efficiency of increasingly busy ATUs.

  12. Computerized fetal heart rate monitoring after vibroacoustic stimulation in the anencephalic fetus.

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    Park, Yong-Jin; Park, Seon-Hye; Kim, Young-Jae; Hoh, Jeong-Kyu; Park, Young-Sun; Park, Moon-Il

    2010-09-01

    To quantify changes in fetal heart rate (FHR) parameters after vibroacoustic stimulation (VAS) and to evaluate the usefulness of VAS testing (VAST) in anencephalic fetuses. Our findings may also help to clarify the route(s) of vibration and sound transmission during VAST. We obtained the antepartum FHR tracings of 16 anencephalic fetuses, including both the nonstress test (NST) and VAST. Using a computerized monitoring system, HYFM, we determined all FHR parameters from data collected for 10 min before and 10 min after VAS, at successive gestational stages. We observed three false reactive responses at term. The false reactive rate for VAST (3/16) was higher than that for NST (1/16). No FHR parameters increased significantly after VAS except for the number of fetal movements (FM), which increased significantly in all gestational groups (25th-32nd and 33rd-40th weeks). These findings call attention to an increased probability of a false reactive response in VAST analysis, when the fetus is affected by a CNS disorder. Increased numbers of FM after VAS suggest that the vibratory pathway is more likely to elicit fetal response than the auditory pathway in this setting, and that the vibratory stimulation travels by subcortical rather than by cortical pathways. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

  13. The effects of maternal depression on fetal heart rate response to vibroacoustic stimulation.

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    Allister, L; Lester, B M; Carr, S; Liu, J

    2001-01-01

    To better understand the effects of untreated maternal depression on the fetus, this study examined fetal heart rate (FHR) and FHR reactivity to vibroacoustic stimulation in pregnant women with untreated depression. The 20 participants were 32- to 36-week pregnant women divided into groups with depression (N = 10) and without depression (N = 10) based on the Beck Depression Inventory (BDI; Beck, 1977; Beck & Steer, 1987). Participants were attached to a fetal heart monitor, and 10 min of baseline FHR were recorded. A vibroacoustic stimulus (VAS) was presented, and an additional 10 min of FHR were recorded. Fetuses of mothers with depression had an elevated baseline FHR and a 3.5-fold delay in return to baseline FHR after VAS presentation. Additionally, mothers with depression had significantly higher anxiety levels and took fewer prenatal vitamins during pregnancy. Delayed habituation of FHR in the fetuses of mothers with depression may be due to alterations in the internal hormonal environment and could have implications for postnatal information processing.

  14. The Effect of Vibroacoustic Stimulation and Music on Fetal Movement

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    Masoume Pirhadi

    2015-09-01

    Full Text Available Introduction Fetal movement started at the 7th weeks of pregnancy and by the end of pregnancy will gradually be perfect and harmonious. Near-term fetuses can discriminate acoustic features, such as frequencies and spectra, and process complex auditory streams. In this study, we aimed to evaluate fatal movement in response to music and vibration stimulation. Materials and Methods This study is a clinical trial that was conducted in two groups and two-steps. Participants were pregnant women (primigravida who have referring to the Shahid Beheshti Hospital in Isfahan during 2013 to receive routine prenatal care. The 64 pregnant women (32-36 weeks were randomly assigned to the groups of Vibroacoustic stimulation (n= 32 and Music (n=32. They were stimulated immediately after the first non stress test and before the second test. The researchers’ evaluated and analyzed possible changes in non-stress test results using SPSS software version 20. Results Mean age of the subjects in vibroacoustic group and in music group were (25.5±2.6 (24.9±4.4 respectively. Paired t-test showed there was no relationship between the average number of acceleration of the fetal heart rate before and after the intervention (P>0.05.On the other hand, there was a significant correlation between the average number of fetal movements in the music group before and after the intervention (P

  15. Effects of vibroacoustic stimulation in music therapy for palliative care patients: a feasibility study.

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    Warth, Marco; Kessler, Jens; Kotz, Svenja; Hillecke, Thomas K; Bardenheuer, Hubert J

    2015-12-15

    The present study aimed at examining whether methodological strategies from a previously implemented study design could be transferred to the evaluation of the psychological and physiological effects of a music therapy intervention working with vibroacoustic stimulation in palliative care. Nine participants suffering from advanced cancer took part in single-sessions of music therapy, lasting for 30 min. The live music therapy intervention utilized singing chair sounds and vocal improvisation. Visual analogue scales (VAS) were used to assess self-ratings of pain, relaxation, and well-being before and after each session. During the intervention, we continuously recorded heart rate variability (HRV) as a measure of autonomic functioning. Data collection was complemented by a semi-structured interview to explore subjective experiences in more detail. Feasibility was defined as the ability to complete 80 % of the sessions in accordance with the study protocol. In 5 out of 9 sessions (55 %) it was possible to deliver the intervention and obtain all data as intended. VAS assessment was feasible, although graphical and statistical examination revealed only marginal mean changes between pre and post. HRV recordings were subject to artifacts. While HRV parameters differed between individuals, mean changes over time remained relatively constant. Interview data confirmed that the individual perception was very heterogeneous, ranging from "calming" to "overwhelming". The criterion of feasibility was not met in this study. Physiological data showed high attrition rates, most likely due to movement artifacts and reduced peripheral blood flow in some participants' extremities. Examination of individual-level trajectories revealed that vibroacoustic stimulation may have an impact on the autonomic response. However, the direction and mechanisms of effects needs to be further explored in future studies. German Clinical Trials Register - DRKS00006137 (July 4(th), 2014).

  16. Fetal exposures to sound and vibroacoustic stimulation.

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    Gerhardt, K J; Abrams, R M

    2000-12-01

    Sounds in the environment of a pregnant woman penetrate the tissues and fluids surrounding the fetal head and stimulate the inner ear through a bone conduction route. The sounds available to the fetus are dominated by low-frequency energy, whereas energy above 0.5 kHz is attenuated by 40 to 50 dB. The fetus easily detects vowels, whereas consonants, which are higher in frequency and less intense than vowels, are largely unavailable. Rhythmic patterns of music are probably detected, but overtones are missing. A newborn human shows preference for his/her mother's voice and to musical pieces to which he/she was previously exposed, indicating a capacity to learn while in utero. Intense, sustained noises or impulses produce changes in the hearing of the fetus and damage inner and outer hair cells within the cochlea. The damage occurs in the region of the inner ear that is stimulated by low-frequency sound energy.

  17. Cross-over trial of fetal heart rate response to halogen light and vibroacoustic stimulation.

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    Bolnick, Jay M; Garcia, Greg; Fletcher, Beverly G; Rayburn, William F

    2006-04-01

    The purpose of this study was to compare the effect of halogen light and vibroacoustic stimulation on fetal heart rate (FHR) responsiveness and on nonstress test (NST) results. Sixty consecutively-chosen patients between 33 and 39 weeks of gestation underwent an NST on at least three weekly occasions. Each received halogen light (Vector Compact Sport Spot, Ft Lauderdale, FL, USA), vibroacoustic (SolaTone Artificial Larynx, Temecula, CA, USA), and no stimulation in a randomized order. The transabdominal light or vibroacoustic stimulation lasted for 10 seconds. If no initial FHR acceleration occurred, then the stimulus was repeated 10 minutes later up to a maximum of three times. The investigators who interpreted the FHR patterns were blinded as to the type of stimulus used. Reactive results were present in 171 tests (vibroacoustic: 98.3%; light: 96.6%; none: 93.3%). Compared with no stimulation, the mean difference in time from the onset of recorded "stimulation" to the first FHR acceleration was shorter (p vibroacoustic stimulation (2.6 minutes, 95% CI 0.8-4.4 minutes). The mean time difference until a reactive result was also shorter (p vibroacoustic stimulation (2.4 minutes, 95% CI 0.1-4.7 minutes) than with no stimulation. The need for repeated stimulation during each test was infrequent (light: 5.0%; vibroacoustic: 3.3%). No adverse effect from external stimulation was noted on the FHR tracing. Halogen light stimulation is an acceptable alternative to vibroacoustic stimulation in provoking a more rapid fetal heart rate response and in shortening the time before a reactive nonstress test result.

  18. Vibroacoustic stimulation in abnormal biophysical profile: verification of facilitation of fetal well-being.

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    Papadopoulos, Vassilis G; Decavalas, George O; Kondakis, Xenophon G; Beratis, Nicholas G

    2007-03-01

    To verify the effect of vibroacoustic stimulation on biophysical profile score, with a prospective randomised study. All women with singleton pregnancy, gestational age >or=30 weeks, intact membranes and biophysical profile score vibroacoustic stimulation does not alter test's statistical parameters. 1349 patients were randomised in group A and 1484 in group B (2833 in total). When comparing group A to B, application of vibroacoustic stimulation significantly decreased the number of positive tests (4.74% vs. 6.67%, pVibroacoustic stimulation improves the efficiency of biophysical profile score by decreasing false positive tests and improving test accuracy and should be considered as a means of a more thorough fetal evaluation when fetal compromise is suspected.

  19. Fetal vibroacoustic stimulation in computerized cardiotocographic analysis: the role of short-term variability and approximate entropy.

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    Annunziata, Maria Laura; Scala, Mariamaddalena; Giuliano, Natascia; Tagliaferri, Salvatore; Imperato, Olga Carmela Maria; Esposito, Francesca Giovanna; Campanile, Marta; Di Lieto, Andrea

    2012-01-01

    The aim of this study was to evaluate the impact of vibroacoustic stimulation (VAS) on computerized cardiotocography short-term variability (STV) and approximate entropy (ApEn) in both low- and high-risk pregnancies. VAS was performed on 121 high- and 95 low-risk pregnancies after 10 minutes of continuous quiet, while their FHR parameters were monitored and recorded by cCTG analysis. Fetal heart rate was recorded using a computer-assisted equipment. Baseline FHR, accelerations, decelerations, STV, long-term irregularity (LTI), ApEn, and fetal movements (FMs) were calculated for defined observational periods before VAS and after 10 minutes. Data were also investigated in relationship with the perinatal outcome. In each group of patients, FHR after VAS remained almost unmodified. Fetal movements significantly increased after VAS in both groups. Results show that only in the high-risk pregnancies, the increase of STV and the decrease of ApEn after VAS were significantly associated with favorable perinatal outcomes.

  20. Fetal Vibroacoustic Stimulation in Computerized Cardiotocographic Analysis: The Role of Short-Term Variability and Approximate Entropy

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    Maria Laura Annunziata

    2012-01-01

    Full Text Available The aim of this study was to evaluate the impact of vibroacoustic stimulation (VAS on computerized cardiotocography short-term variability (STV and approximate entropy (ApEn in both low- and high-risk pregnancies. VAS was performed on 121 high- and 95 low-risk pregnancies after 10 minutes of continuous quiet, while their FHR parameters were monitored and recorded by cCTG analysis. Fetal heart rate was recorded using a computer-assisted equipment. Baseline FHR, accelerations, decelerations, STV, long-term irregularity (LTI, ApEn, and fetal movements (FMs were calculated for defined observational periods before VAS and after 10 minutes. Data were also investigated in relationship with the perinatal outcome. In each group of patients, FHR after VAS remained almost unmodified. Fetal movements significantly increased after VAS in both groups. Results show that only in the high-risk pregnancies, the increase of STV and the decrease of ApEn after VAS were significantly associated with favorable perinatal outcomes.

  1. Development of Fetal Movement between 26 and 36 Weeks’ Gestation in Response to Vibro-acoustic Stimulation

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    Marybeth eGrant-Beuttler

    2011-12-01

    Full Text Available Background: Ultrasound observation of fetal movement has documented general trends in motor development and fetal age when motor response to stimulation is observed. Evaluation of fetal movement quality, in addition to specific motor activity, may improve documentation of motor development and highlight specific motor responses to stimulation. Aims: The aim of this investigation was to assess fetal movement at 26 and 36 weeks gestation during three conditions (baseline, immediate response to vibro-acoustic stimulation (VAS, and post-response. Design: A prospective, longitudinal design was utilized. Subjects: Twelve normally developing fetuses, 8 females and 4 males, were examined with continuous ultrasound imaging. Outcome measures: The Fetal Neurobehavioral Coding System (FENS was used to evaluate the quality of motor activity during 10-second epochs over the three conditions. Results: Seventy-five percent of the fetuses at the 26 week assessment and 100% of the fetuses at the 36 week assessment responded with movement immediately following stimulation. Significant differences in head, fetal breathing, general, limb, and mouthing movements were detected between the 26 week and 36 week assessments. Movement differences between conditions were detected in head, fetal breathing, limb, and mouthing movements. Conclusions: Smoother and more complex movement was observed with fetal maturation. Following VAS stimulation, an immediate increase of large, jerky movements suggest instability in fetal capabilities. Fetal movement quality changes over gestation may reflect sensorimotor synaptogenesis in the central nervous system, while observation of immature movement patterns following VAS stimulation may reflect movement pattern instability.

  2. Fetal habituation to vibroacoustic stimulation in uncomplicated postterm pregnancies.

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    van Heteren, C F; Boekkooi, P F; Schiphorst, R H; Jongsma, H W; Nijhuis, J G

    2001-08-01

    Testing of fetal habituation to repeated vibroacoustic stimulation might give additional information concerning the fetal condition and central nervous system (CNS) functioning in postterm pregnancies. This study is designed to investigate whether healthy postterm fetuses are able to habituate and if so, if the habituation pattern of postterm fetuses differs from that of term fetuses. Twenty women with an uncomplicated pregnancy beyond 41 weeks gestational age (GA) participated, and 37 women with a GA between 37 and 40 weeks served as controls. The vibroacoustic stimulus was repeatedly applied to the maternal abdomen above the fetal legs for a period of 1s every 30s. A fetal trunk movement within 1s of stimulus application was considered a positive response. Lack of response to four consecutive stimuli indicated habituation. The habituation rate is defined as the number of stimuli applied before the fetus stopped responding. Data were compared using Mann-Whitney U test. Of the 18 postterm fetuses in which the presence or absence of habituation could be established, 14 habituated and four persisted in responding. Twenty-six of the 32 term fetuses, in which the presence or absence of habituation could be established, habituated and six persisted in responding. The habituation rate varied widely in postterm (median of eight stimuli, quartile ranges of 6 and 18) as well as in term fetuses (median of 9.5 stimuli, quartile ranges of 6 and 15). There was no difference in median habituation rate between postterm and term fetuses. The ongoing maturation of the CNS in the last weeks of pregnancy appears not to be reflected in the fetal habituation pattern. Furthermore, the interfetal variability in habituation of healthy postterm fetuses is such that testing of habituation appears not to be suitable for the identification of the fetus at risk for an adverse neonatal outcome.

  3. The responses to repeated vibroacoustic stimulation in a fetus with trisomy 18.

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    van Heteren, C F; Focco Boekkooi, P; Jongsma, H W; Nijhuis, J G

    2001-05-01

    Observation of the fetal movement and fetal heart rate responses to repeated vibroacoustic stimulation might be useful as a measure to assess fetal well-being. Studies of abnormal fetuses are needed to gain insight in the spectrum of possible responses to stimulation. We present a case of a fetus with trisomy 18 that failed to respond to repeated stimulation.

  4. Comparison of halogen light and vibroacoustic stimulation on nonreactive fetal heart rate pattern.

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    Rahimikian, Fatemeh; Rahiminia, Tahereh; Modarres, Maryam; Mehran, Abbas

    2013-03-01

    One of the first-line assessment tools for fetal surveillance is nonstress test (NST), although it is limited by a high rate of false-nonreactive results. This study was performed to investigate if external stimulation from vibroacoustic and halogen light could help in provoking fetal responsiveness and altering NST results. This is a clinical trial. Sampling was done from April to July 2010. One hundred pregnant women with nonreactive NST for 20 min were allocated in two groups: Vibroacoustic stimulated NST (VNST, n = 50) who received vibration from a standard fetal vibratory stimulator and halogen light stimulated NST (LNST, n = 50) who received a halogen light source for 3 and 10 sec, respectively. Results were compared together and then compared to biophysical profile (BPP) scores as a backup test. We used Mann-Whitney U test, Chi-square test, and Fisher's exact test to compare the variables in the two groups through SPSS version 14. P vibroacoustic stimulation group changed to reactive patterns. Time to onset of the first acceleration (VNST: 2.17 min; LNST: 2.27 min) and the test duration (VNST: 4.91 min; LNST: 5.26 min) were the same in the two groups. In VNST 89.5% and in LNST 87.5% of nonreactivity followed by score 8 in BPP. There was no significant relation between stimulus NSTs and BPPs. Vibroacoustic and light stimulation offer benefits by decreasing the incidence of nonreactive results and reducing the test time. Both halogen light stimulation and vibroacoustic stimulation are safe and efficient in fetal well-being assessment services.

  5. Vibroacoustic stimulation enhances visualization of the four-chamber cardiac view in the third trimester.

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    Lazebnik, N; Hill, L M; Costantino, J P; Many, A; Martin, J G

    1996-11-01

    The objective of this study was to determine whether vibroacoustic stimulation would improve the visualization rate of the four-chamber cardiac view. Patients between 26 and 42 weeks' gestation were considered to be candidates for this study if the amniotic fluid index (AFI) was between 8.0 and 24.0 cm, no malformations were detected on a careful fetal anatomical survey and a four-chamber cardiac view was not obtainable. Once a four-chamber view was considered to be not obtainable due to fetal position, the patient was asked to withdraw a sealed envelope and was assigned to either the study or the control group. The 164 study patients received one to three 3-s vibroacoustic stimulations. Five minutes later a second attempt was made to visualize the four-chamber view adequately. The control group consisted of another 198 subjects in whom a four-chamber view could not be obtained. The control group did not receive vibroacoustic stimulation. A similar 5-min time interval was allowed to elapse before an attempt was made to visualize the four-chamber view. The study and control groups were similar with respect to fetal presentation, placental location, fetal weight category, biophysical profile score, gestational age, AFI and estimated fetal weight. The rate of the four-chamber view was significantly higher among fetuses receiving vibroacoustic stimulation (20.1%), in comparison to the control group (11.1%) (p = 0.019). Successful repositioning was more likely among fetuses with estimated fetal weight between 2251 and 3050 g, and at a gestational age between 33.1 and 37.0 weeks. We conclude that in a selected group of patients vibroacoustic stimulation can be used to enhance visualization of the four-chamber view.

  6. The effect of antenatal steroid administration on the fetal response to vibroacoustic stimulation.

    Science.gov (United States)

    Rotmensch, S; Celentano, C; Liberati, M; Sadan, O; Glezerman, M

    1999-11-01

    Betamethasone transiently suppresses multiple fetal biophysical activities, including breathing movements, limb and trunk movements, heart rate variability, and heart rate accelerations. Unnecessary iatrogenic delivery of preterm fetuses due to the false diagnosis of fetal compromise has been described in this setting. The sonographically observed startle response of the fetus to vibroacoustic stimulation has been described as another modality to provide reassurance about fetal well-being. It is unknown, however, whether the startle response is also suppressed by betamethasone. The purpose of this study was to examine the effect of betamethasone on this biophysical parameter. A prospective cohort study. Vibroacoustic stimulation was applied to the maternal abdomen and fetal movement responses were sonographically observed prior to (0 hours), 48 hours after, and 96 hours after betamethasone administration. We recorded the presence or absence of the fetal startle response, and, if a response was present, graded semi-quantitatively the intensity of the movements (vigorous versus sluggish). Twenty-two of 26 fetuses (84.6%) displayed a vigorous vibroacoustic startle response prior to betamethasone administration, in comparison to three of 26 fetuses (11.5%) at 48 hours after exposure (pvibroacoustic stimulation. Accordingly, this modality cannot be used for the ascertainment of fetal well-being of steroid exposed fetuses. Betamethasone seems to suppress central nervous system dependent biophysical activities. including the brain-stem dependent vibroacoustic startle reflex.

  7. Combination of vibroacoustic stimulation and acute variables of mFBP as a simple assessment method of low-risk fetuses.

    Science.gov (United States)

    Petrović, Oleg; Finderle, Aleks; Prodan, Mirko; Skunca, Elvira; Prpić, Igor; Zaputović, Sanja

    2009-02-01

    To observe a rate of fetal breathing and gross body movement appearance as physiologic reactions to the external vibroacoustic stimulation (VAS) and to establish a rapid and reliable antepartal method for accurate selecting of non-compromised fetuses in the low-risk population. Actual condition of 742-term and near-term structurally normal and otherwise healthy singleton fetuses with favourable outcome was assessed by previously established combination of the modified fetal biophysical profile and VAS. Only inactive fetuses at the beginning of the testing were included in the study. The combined biophysical testing has been started by a transabdominal real-time ultrasound examination, followed by vibroacoustic stimulus applied over the fetal head for 5 s during fetal quiescence. Fetal breathing and gross body movements were observed with particular attention in each case at measured time intervals from the application of external VAS until the moment at which either the first 60-s episode of breathing movements or all three fetal gross body movements were detected. Obtained results have been presented numerically in 5-min periods and cumulative percentages. After the external VAS, 84.5% of studied fetuses successfully manifested their normal breathing or gross body movements in the first 5 min of the modified biophysical testing. Furthermore, approximately 96% of them were able to demonstrate at least one of these two biophysical activities after 6-7 min. Because of its simplicity, non-invasiveness, independence of precise gestational dating, reproducibility and immediate individual results, ultrasonographic observation of normal fetal breathing and/or gross body movements after the external VAS stands a real chance to become a nearly optimal antenatal test for accurate and rapid information of actual non-compromised fetal condition. Authors strongly believe that the described antenatal method should represent a rather efficient assessment procedure of fetal well

  8. Blunted fetal response to vibroacoustic stimulation following chronic exposure to propranolol.

    Science.gov (United States)

    Sherer, D M; Bentolila, E

    1998-08-01

    A recent, prospective randomized trial has suggested that long-term use of prophylactic beta-adrenergic blocking agents may slow the rate of aortic dilation in those patients with Marfan's syndrome exhibiting evidence of existing dilation. Accordingly, administration of such medication from the midtrimester onward has been advocated in these patients. Acute oral administration of propranolol (80 mg) has been shown to depress fetal heart rate response to vibroacoustic stimulation. We present a case in which chronic administration of propranolol 150 mg/day to a patient with Marfan's syndrome with existing aortic root dilation was associated with repeated abnormal intrapartum fetal heart rate responses to vibroacoustic stimulation. Subsequent delivery of a nonhypoxic, nonacidotic infant suggests that maternal administration of beta-blockers should be considered in the interpretation of results of fetal vibroacoustic stimulation. This case also supports that in similar clinical presentations, ultrasonographic confirmation of the fetal startle response, or alternatively observation of the resulting fetal recoil may be utilized rather than the fetal heart rate, which may be modulated by maternal medications.

  9. Distance from an intrauterine hydrophone as a factor affecting intrauterine sound pressure levels produced by the vibroacoustic stimulation test.

    Science.gov (United States)

    Eller, D P; Scardo, J A; Dillon, A E; Klein, A J; Stramm, S L; Newman, R B

    1995-08-01

    The purpose of this study was to determine whether intrauterine sound pressure levels produced by vibroacoustic stimulation were associated with distance from an intrauterine hydrophone in human parturients and to evaluate the effects of distance on the spectrum of the stimulus. Measurements of intrauterine sound were taken in eight volunteer parturients in normal active-phase labor by use of an intrauterine hydrophone. Vibroacoustic stimulation was performed on the maternal abdomen directly overlying the hydrophone; at distance of 5, 10, 15, 20, and 25 cm from the hydrophone; and at the maternal sternum. Intrauterine sound pressure levels were tape-recorded for later analysis. Fetal heart rate and fetal movement were assessed with each vibroacoustic stimulation. Spectral analyses were performed by taking the fast Fourier transform of the tape-recorded stimulation at each position. Analysis of variance with repeated measures indicated a statistically significant decrease (F = 4.1, p = 0.004) in the sound pressure levels as distance increased. Spectral analysis indicated large variability between and within subjects. Sound exposure of the fetal ear is on average decreased as the distance between the ear and the vibroacoustic stimulation is increased. The spectrum of the stimulus produced with vibroacoustic stimulation is highly variable.

  10. Frequency of positive results of vibroacoustic stimulation test in evaluating fetus health of pregnant women with non-reactive NST

    Directory of Open Access Journals (Sweden)

    soheila Akbari

    2014-03-01

    Full Text Available Background : Non-Stress Test (NST is one of the most common methods used to evaluat fetus health, which its results are presented as reactive and non-reactive. One of the limitations of this test is the high number of false non-reactive cases. Different studies have suggested a combination of vibroacoustic stimulation and NST to reduce the number of non-reactive cases and duration of the test. Materials and Methods: The present study examined a group of tests, and used simple randomized sampling. The number of the sample was 55 individuals and the data collection tools were NST, sonography instruments, NST result paper, a tooth brusher, a watch, a demographic questionnaire, and a checklist. Vibroacoustic stimulation with an electronic brush was performed on fetus head situated on mother’s abdomen for 3 seconds and then NST was continued for a further 20 minutes. Then the results were recorded. The obtained data were gathered by SPSS 19 software, and analyzed using descriptive statistics. Results: In this study, 85.5% of the non-reactive cases changed into reactive through vibroacoustic stimulation. The amount of false positive was lower with vibroacoustic stimulation in comparison with NST. Conclusion: Vibroacoustic stimulation, as a technique for evaluating fetus health, makes it possible to save time, costs and personnel. It is also leads to sooner and better diagnosis of fetus health.

  11. Effect of abdominal vibroacoustic stimulation on sound and acceleration levels at the head of the fetal sheep.

    Science.gov (United States)

    Abrams, R M; Peters, A J; Gerhardt, K J

    1997-08-01

    To measure the vibratory response of the fetal head and abdominal wall in sheep during vibroacoustic stimulation. A piezoresistive accelerometer was attached to the skulls of seven sheep fetuses (128-134 days' gestational age), and a miniature hydrophone was attached to the skin overlying the fetal temporal bone. During fetal preparation and vibroacoustic stimulation procedures, ewes were anesthetized and supine. Vibroacoustic stimulation of the maternal abdomen was produced by each of two clinical devices that differed in spectral content, and an electric toothbrush. The approximate fundamental frequencies (f0) and first overtones (f1), as determined by both recordings of intrauterine sound pressure level and fetal head acceleration, were as follows: fetal acoustic stimulator, 75 and 150 Hz; electronic larynx, 150 and 300 Hz; and electric toothbrush, 25 and 50 Hz, respectively. At fundamental frequencies and first overtones, the ranges of fetal head accelerations (expressed in 1/12-octave bands) were as follows: fetal acoustic stimulator, 10-53 and 25-224 mm/sec2; electronic larynx, 10-53 and 18-114 mm/sec2; and electric toothbrush, 33-792 and 8-116 mm/sec2, respectively. Sound pressure levels exceeded 110 dB in all cases. High sound pressure levels in the uterus were proportional to fetal head vibration levels. Vibroacoustic stimulation of the surface of the abdomen of pregnant sheep is accompanied by both acoustic and vibratory exposure of the fetus.

  12. Vibroacoustic stimulation for fetal assessment in labour in the presence of a nonreassuring fetal heart rate trace.

    Science.gov (United States)

    East, C E; Smyth, R; Leader, L R; Henshall, N E; Colditz, P B; Tan, K H

    2005-04-18

    Fetal vibroacoustic stimulation is a simple, non-invasive technique where a device is placed on the maternal abdomen over the region of the fetal head and sound is emitted at a predetermined level for several seconds. It is hypothesized that the resultant startle reflex in the fetus and subsequent fetal heart rate acceleration or transient tachycardia following vibroacoustic stimulation provide reassurance of fetal well-being. This technique has been proposed as a tool to assess fetal well-being in the presence of a non-reassuring cardiotocographic trace during the first and second stages of labour. To evaluate the clinical effectiveness and safety of vibroacoustic stimulation in the assessment of fetal well-being during labour, compared with mock or no stimulation for women with a singleton pregnancy exhibiting a non-reassuring fetal heart rate pattern. We searched the Cochrane Pregnancy and Childbirth Group Trials Register (30 September 2004), the Cochrane Central Register of Controlled Trials (The Cochrane Library, Issue 1, 2004), MEDLINE (January 1966 to January 2005), EMBASE (January 1966 to January 2005) and reference lists of all retrieved articles. We sought unpublished trials and abstracts submitted to major international congresses and contacted expert informants. All published and unpublished randomised trials that compared maternal and fetal/neonatal/infant outcomes when vibroacoustic stimulation was used to evaluate fetal status in the presence of a non-reassuring cardiotocographic trace during labour, compared with mock or no stimulation. Two independent review authors identified potential studies from the literature search and assessed them for methodological quality and appropriateness of inclusion, using a data extraction form. Attempts to contact study authors for additional information were unsuccessful. The search strategies yielded six studies for consideration of inclusion. However, none of these studies fulfilled the requirements for

  13. The relationship between the response to external light stimulation and behavioral states in the human fetus: how it differs from vibroacoustic stimulation.

    Science.gov (United States)

    Kiuchi, M; Nagata, N; Ikeno, S; Terakawa, N

    2000-05-01

    To determine the effects of external light stimulation on fetal behavioral states and know the difference from those of vibroacoustic stimulation. A flashlight and a vibroacoustic stimulator was applied directly on the maternal abdomen to determine the response of 56 normal fetuses at 36-40 weeks gestation. Fetal heart rate (FHR) and body movements were recorded using an actocardiograph, and fetal eye movements were observed using real-time ultrasonography. Using Nijhuis's criteria, the fetal behavioral states (1F-4F) were determined. FHR acceleration was considered a fetal response to the stimulations. The lag time between stimulation and fetal response was within 4 s. A positive response rate to the light stimulation was higher at behavioral states 2F (82%) and 3F (83%) than at state 1F (4%). Light stimulation changed the behavioral state of two of the six 3F fetuses (33%) from 3F to 4F. No change of state was observed in fetuses that were in states 1F and 2F. For vibroacoustic stimulation, fetal response was 100% positive and changes of states were observed frequently irrespective of the behavioral state before the stimulation. Fetal response to light stimulation is closely connected to fetal behavioral states and may reflect some distinct stages of the sleep-wakefulness cycle.

  14. Fetal habituation to vibroacoustic stimulation in relation to fetal states and fetal heart rate parameters.

    Science.gov (United States)

    van Heteren, C F; Boekkooi, P F; Jongsma, H W; Nijhuis, J G

    2001-03-01

    Fetal habituation to repeated stimulation has the potential to become a tool in the assessment of fetal condition and of the function of the fetal central nervous system (CNS). However, the influence of fetal quiescence and activity on habituation remains to be clarified. We studied habituation and the influence of fetal state and fetal heart rate (FHR) parameters on habituation in healthy term fetuses. We studied habituation in 37 healthy fetuses in two tests with an interval of 10 min. The vibroacoustic stimuli were applied to the maternal abdomen above the fetal legs for a period of 1 s every 30 s. A fetal trunk movement within 1 s after stimulation was defined as a positive response. Habituation rate is defined as the number of stimuli applied before an observed non-response to four consecutive stimuli. The FHR patterns (FHRP) of the 10 min observation period before and after the tests were visually classified. Fetal states were defined according to the FHRP. Baseline FHR, FHR variability and the number of accelerations were calculated in a subgroup of 25 fetuses. Of the 32 fetuses that responded normally during the first test, 26 habituated and six had persistent responses. The median habituation rate decreased significantly in the second test (P=0.001). There was no difference in habituation rate between fetuses that where initially in a quiet state and those in an active state. The FHR parameters before the first test and the difference between these FHR parameters before and after the test did not correlate with the habituation rate. Although the majority of healthy fetuses was able to habituate, the interfetal variability in habituation performance is such that testing of habituation seems not to be a sensitive tool for the assessment of the fetal CNS. This variability is neither the result of differences in fetal state nor of the various FHR parameters before testing, nor of the difference in change of FHR parameters arising from stimulation.

  15. Evaluation of a multi-component approach to cognitive-behavioral therapy (CBT) using guided visualizations, cranial electrotherapy stimulation, and vibroacoustic sound.

    Science.gov (United States)

    Rogers, Donna R B; Ei, Sue; Rogers, Kim R; Cross, Chad L

    2007-05-01

    This pilot study examines the use of guided visualizations that incorporate both cognitive and behavioral techniques with vibroacoustic therapy and cranial electrotherapy stimulation to form a multi-component therapeutic approach. This multi-component approach to cognitive-behavioral therapy (CBT) was used to treat patients presenting with a range of symptoms including anxiety, depression, and relationship difficulties. Clients completed a pre- and post-session symptom severity scale and CBT skills practice survey. The program consisted of 16 guided visualizations incorporating CBT techniques that were accompanied by vibroacoustic therapy and cranial electrotherapy stimulation. Significant reduction in symptom severity was observed in pre- and post-session scores for anxiety symptoms, relationship difficulties, and depressive symptoms. The majority of the clients (88%) reported use of CBT techniques learned in the guided visualizations at least once per week outside of the sessions.

  16. The effects of lysergic acid diethylamide on the response to field stimulation of the rat vas deferens and the rat and cat anococcygeus muscles.

    Science.gov (United States)

    Gillespie, J S; McGrath, J C

    1975-08-01

    1. The effect of lysergic acid diethylamid (LSD) on the response to field stimulation in vitro of the rat vas deferens and anococcygeus muscle was examined. 2. LSD in concentrations from 10(-9) to 10(-6) M caused an increase in tone or rhythmic activity in both tissues, effects identical to those produced by guanethidine or tyramine. The motor effects of all three drugs were abolished by phentolamine 2 x 10(-6) M. Methysergide 2 x 10(-7) M given before LSD reduced the motor effect but was ineffective once the LSD contraction had developed. 3. LSD 10(-9) to 10(-6) M reduced and eventually abolished the response to motor adrenergic nerve stimulation in the anococcygeus muscle with no effect on the response to noradrenaline (NA) and no evidence of differential sensitivity according to the number of stimulating pulses. In the vas deferens LSD abolished the initial twitch component with no effect on the secondary slow contraction. LSD had no effect on the response to inhibitory nerve stimulation in the anococcygeus. 4. These results suggest that in the anococcygeus LSD closely resembles guanethidine in its effects as an adrenergic neurone blocking drug with indirect sympathomimetic actions. In the vas deferens these properties would explain the block of the initial twitch component in the motor response to field stimulation and the increase in rhythmic activity but do not explain the resistance of the secondary slow component of the motor response.

  17. Antenatal fetal assessment: contraction stress test, nonstress test, vibroacoustic stimulation, amniotic fluid volume, biophysical profile, and modified biophysical profile--an overview.

    Science.gov (United States)

    Devoe, Lawrence D

    2008-08-01

    Antenatal fetal assessment was introduced into the United States in the 1970s. The initial antepartum test, the oxytocin challenge test, later renamed as the contraction stress test, became the gold standard for fetal surveillance. Its labor intensive requirements and contraindications made it inapplicable to some high-risk pregnancies. Other testing schemes were developed subsequently, the nonstress test and its alternative, vibroacoustic stimulation, the semiquantitative assessment of amniotic fluid volume, the biophysical profile and its modified version, the modified biophysical profile. This article is a brief critical review of these testing methods and focuses on the following: (1) physiologic bases; (2) testing methodologies; (3) supportive evidence from randomized controlled and observational trials; and (4) areas needing further investigation.

  18. Vibroacoustic disease.

    Science.gov (United States)

    Branco, N A A Castelo; Alves-Pereira, M

    2004-01-01

    Vibroacoustic disease (VAD) is a whole-body, systemic pathology, characterized by the abnormal proliferation of extra-cellular matrices, and caused by excessive exposure to low frequency noise (LFN). VAD has been observed in LFN-exposed professionals, such as, aircraft technicians, commercial and military pilots and cabin crewmembers, ship machinists, restaurant workers, and disk-jockeys. VAD has also been observed in several populations exposed to environmental LFN. This report summarizes what is known to date on VAD, LFN-induced pathology, and related issues. In 1987, the first autopsy of a deceased VAD patient was performed. The extent of LFN induced damage was overwhelming, and the information obtained is, still today, guiding many of the associated and ongoing research projects. In 1992, LFN-exposed animal models began to be studied in order to gain a deeper knowledge of how tissues respond to this acoustic stressor. In both human and animal models, LFN exposure causes thickening of cardiovascular structures. Indeed, pericardial thickening with no inflammatory process, and in the absence of diastolic dysfunction, is the hallmark of VAD. Depressions, increased irritability and aggressiveness, a tendency for isolation, and decreased cognitive skills are all part of the clinical picture of VAD. LFN is a demonstrated genotoxic agent, inducing an increased frequency of sister chromatid exchanges in both human and animal models. The occurrence of malignancies among LFN-exposed humans, and of metaplastic and displastic appearances in LFN-exposed animals, clearly corroborates the mutagenic outcome of LFN exposure. The inadequacy of currently established legislation regarding noise assessments is a powerful hindrance to scientific advancement. VAD can never be fully recognized as an occupational and environmental pathology unless the agent of disease--LFN--is acknowledged and properly evaluated. The worldwide suffering of LFN-exposed individuals is staggering and it is

  19. Skylab vibroacoustic test program

    Science.gov (United States)

    Jewell, R. E.

    1974-01-01

    Vibroacoustic testing was performed on the orbital workshop dynamic test article and the payload assembly, the two major elements of the Skylab payload. The testing was conducted on each of the Skylab elements separately in the reverberation chamber at the Johnson Space Center. The two test configurations were high fidelity flight article simulations. The testing was conducted in two phases; in the first phase, acoustic tests were performed at levels simulating the lift-off and atmospheric flight acoustic criteria. In the second phase, low frequency sinusoidal vibration tests were conducted to obtain modal response data. The objectives of the Skylab vibroacoustic test program were to: verify the vibration design and test criteria; qualify selected flight components to the vibroacoustic criteria; and verify analytical models used for dynamic load analyses. This paper describes the vibroacoustic testing and discusses the results.

  20. Positive Emotional Experience: Induced by Vibroacoustic Stimulation Using a Body Monochord in Patients with Psychosomatic Disorders: Is Associated with an Increase in EEG-Theta and a Decrease in EEG-Alpha Power.

    Science.gov (United States)

    Sandler, H; Tamm, S; Fendel, U; Rose, M; Klapp, B F; Bösel, R

    2016-07-01

    Relaxation and meditation techniques are generally characterized by focusing attention, which is associated with an increase of frontal EEG Theta. Some studies on music perception suggest an activation of Frontal Midline Theta during emotionally positive attribution, others display a lateralization of electrocortical processes in the attribution of music induced emotion of different valence. The present study examined the effects of vibroacoustic stimulation using a Body Monochord and the conventional relaxation music from an audio CD on the spontaneous EEG of patients suffering from psychosomatic disorders (N = 60). Each treatment took about 20 min and was presented to the patients in random order. Subjective experience was recorded via self-rating scale. EEG power spectra of the Theta, Alpha-1 and Alpha-2 bands were analysed and compard between the two treatment conditions. There was no lateralization of electrocortical activity in terms of the emotional experience of the musical pieces. A reduction in Alpha-2 power occurred during both treatments. An emotionally positive attribution of the experience of the vibroacoustically induced relaxation state is characterized by a more pronounced release of control. In the context of focused attention this is interpreted as flow experience. The spontaneous EEG showed an increase in Theta power, particularly in the frontal medial and central medial area, and a greater reduction in Alpha-2 power. The intensity of positive emotional feelings during the CD music showed no significant effect on the increase in Theta power.

  1. Modificações da hemodinâmica fetal pelo estímulo sonoro: avaliação pela dopplervelocimetria colorida Vibro-acoustic stimulation induced hemodynamic fetal changes assessed by color doppler

    Directory of Open Access Journals (Sweden)

    Francisco Mauad Filho

    1999-04-01

    Full Text Available Objetivos: verificar se ocorrem ou não alterações hemodinâmicas na aréria cerebral média (ACM aferido pela dopplervelocimetria colorida após realização de um estímulo sonoro. Métodos: trinta fetos de gestantes consideradas clinicamente normais com idade gestacional igual ou superior a 28 semanas foram submetidos a um estímulo sonoro. Examinamos as alterações da velocidade sangüínea na ACM fetal por meio do índice de resistência e da freqüência cardíaca fetal, pelo doppler colorido, antes e depois do estímulo acústico. Resultados: a média da freqüência cardíaca fetal (FCF antes do estímulo sonoro foi de 142,41 batimentos por minuto (bpm com desvio padrão de 9,01 e faixa de variação de 122 a 162 bpm. Após o estímulo sonoro, a média da FCF foi de 159,44 bpm com desvio padrão de 15,49, com faixa de variação de 130 a 187 bpm (pPurpose: to determine the possible occurrence of hemodynamic changes in the middle cerebral artery of the fetus (MCA using color doppler after vibro-acoustic stimulation. Methods: thirty fetuses from pregnant women considered to be clinically normal, with a gestational age of 28 weeks or more were submitted to vibro-acoustic stimulation. We examined the changes in blood flow rate in the middle cerebral artery of the fetus on the basis of resistance index (RI and fetal heart rate (FHR by color doppler before and after the sound stimulus. Results: mean FHR before vibro-acoustic stimulation was 142.41 beats per minute (bpm with a standard deviation of 9.01 and a range of 122 to 162 bpm. After stimulation, mean FHR was 159.44 bpm with a standard deviation of 15.49 and a range of 130 to 187 bpm (p<0.01. Mean RI in the MCA of the fetuses was 75.89% (range: 64 to 91% before the experiment. After the vibro-acoustic stimulation, mean RI was 66.93% (range: 47 to 83%; p < 0.01. Conclusions: we observed that a sound stimulus provokes the well-known immediate and significant elevation of FHR and a

  2. Vibro-acoustics

    CERN Document Server

    Nilsson, Anders

    2015-01-01

    This three-volume book gives a thorough and comprehensive presentation of vibration and acoustic theories. Different from traditional textbooks which typically deal with some aspects of either acoustic or vibration problems, it is unique of this book to combine those two correlated subjects together. Moreover, it provides fundamental analysis and mathematical descriptions for several crucial phenomena of Vibro-Acoustics which are quite useful in noise reduction, including how structures are excited, energy flows from an excitation point to a sound radiating surface, and finally how a structure radiates noise to a surrounding fluid. Many measurement results included in the text make the reading interesting and informative. Problems/questions are listed at the end of each chapter and the solutions are provided. This will help the readers to understand the topics of Vibro-Acoustics more deeply. The book should be of interest to anyone interested in sound and vibration, vehicle acoustics, ship acoustics and inter...

  3. Vibroacoustic benchmarking; Vibroakustisches Benchmarking

    Energy Technology Data Exchange (ETDEWEB)

    Kaesler, R.; Prinzler, H. [Freudenberg Dichtungs- und Schwingungstechnik KG, Weinheim (Germany). Technische Entwicklungszentrum

    2000-03-01

    Improved driving comfort is one of the main enhancements in the automotive industry today. It affects not only the constructive design of a car and its equipment but also the vibroacoustic adaptation of the entire vehicle. For several years now, Freudenberg Dichtungs- und Schwingungstechnik has been benchmarking automobiles with respect to their vibroacoustic performance, with the aim of optimising the vibrational layout of engine mounting systems, chassis mounting concepts and finally the overall adaptation of the vehicle. The results of this benchmarking programme are listed according to vehicle class (luxury, mid-range, compact or subcompact class) and constitute an impressive vibroacoustic assessment of current developments in this field. (orig.) [German] Die Steigerung des Fahrkomforts gehoert zu den aktuellen Hauptentwicklungen der Fahrzeughersteller. Dies betrifft nicht nur die konstruktive Gestaltung und Ausstattung der Kraftfahrzeuge, sondern insbesondere die vibroakustische Abstimmung des Gesamtfahrzeugs. Freudenberg Dichtungs- und Schwingungstechnik fuehrte seit mehreren Jahren ein vibroakustisches Fahrzeug-Benchmarking durch, um die schwingungstechnische Auslegung von Aggregatelagerungssystem, Fahrwerklagerungskonzepten und in der Endstufe die Gesamtabstimmung zu optimieren. Die Ergebnisse werden nach Fahrzeugklassen (Luxus-, Mittel-, Kompaktklasse und Kleinwagen) geordnet und stellen eine vibroakustische Bestandsaufnahme der aktuellen Entwicklungen dar. (orig.)

  4. pKI values of prazosin and idazoxan for receptors stimulated by neuronally released transmitter in the epididymal portion of rat isolated vas deferens.

    OpenAIRE

    Mackay, D; Kengatharan, M

    1994-01-01

    1. A new method has been used to measure pKI values of prazosin and idazoxan against neuronally-released transmitter in the epididymal portion of the rat isolated vas deferens. The most reproducible results were obtained with a prolonged antagonist equilibration time (1 h). 2. Under these conditions the pKI of prazosin was practically unaffected by addition of alpha, beta-methylene-adenosine-5'-triphosphate (10 microM) to desensitize purinoceptors. Addition of desmethylimipramine (DMI) (0.3 m...

  5. Relaxation – Induced by Vibroacoustic Stimulation via a Body Monochord and via Relaxation Music – Is Associated with a Decrease in Tonic Electrodermal Activity and an Increase of the Salivary Cortisol Level in Patients with Psychosomatic Disorders

    Science.gov (United States)

    Sandler, Hubertus; Fendel, Uta; Buße, Petra; Rose, Matthias; Bösel, Rainer; Klapp, Burghard F.

    2017-01-01

    Vibroacoustic stimulation by a Body Monochord can induce relaxation states of various emotional valence. The skin conductance level (SCL) of the tonic electrodermal activity is an indicator of sympathetic arousal of the autonomic nervous system and thus an indicator of the relaxation response. Salivary cortisol is considered to be a stress indicator of the HPA-axis. The effects of the treatment with a Body Monochord and listening to relaxation music (randomized chronological presentation) on SCL and salivary cortisol in relation to the emotional valence of the experience were examined in patients with psychosomatic disorders (N = 42). Salivary cortisol samples were collected immediately before and after the expositions. Subjective experience was measured via self-rating scales. Overall, both the exposure to the Body Monochord as well as the exposure to the relaxation music induced an improvement of patients’ mood and caused a highly significant reduction of SCL. A more emotionally positive experience of relaxation correlated with a slightly stronger reduction of the SCL. Both treatment conditions caused a slight increase in salivary cortisol, which was significant after exposure to the first treatment. The increase of salivary cortisol during a relaxation state is contrary to previous findings. It is possible that the relaxation state was experienced as an emotional challenge, due to inner images and uncommon sensations that might have occurred. PMID:28114399

  6. Relaxation - Induced by Vibroacoustic Stimulation via a Body Monochord and via Relaxation Music - Is Associated with a Decrease in Tonic Electrodermal Activity and an Increase of the Salivary Cortisol Level in Patients with Psychosomatic Disorders.

    Science.gov (United States)

    Sandler, Hubertus; Fendel, Uta; Buße, Petra; Rose, Matthias; Bösel, Rainer; Klapp, Burghard F

    2017-01-01

    Vibroacoustic stimulation by a Body Monochord can induce relaxation states of various emotional valence. The skin conductance level (SCL) of the tonic electrodermal activity is an indicator of sympathetic arousal of the autonomic nervous system and thus an indicator of the relaxation response. Salivary cortisol is considered to be a stress indicator of the HPA-axis. The effects of the treatment with a Body Monochord and listening to relaxation music (randomized chronological presentation) on SCL and salivary cortisol in relation to the emotional valence of the experience were examined in patients with psychosomatic disorders (N = 42). Salivary cortisol samples were collected immediately before and after the expositions. Subjective experience was measured via self-rating scales. Overall, both the exposure to the Body Monochord as well as the exposure to the relaxation music induced an improvement of patients' mood and caused a highly significant reduction of SCL. A more emotionally positive experience of relaxation correlated with a slightly stronger reduction of the SCL. Both treatment conditions caused a slight increase in salivary cortisol, which was significant after exposure to the first treatment. The increase of salivary cortisol during a relaxation state is contrary to previous findings. It is possible that the relaxation state was experienced as an emotional challenge, due to inner images and uncommon sensations that might have occurred.

  7. Relaxation - Induced by Vibroacoustic Stimulation via a Body Monochord and via Relaxation Music - Is Associated with a Decrease in Tonic Electrodermal Activity and an Increase of the Salivary Cortisol Level in Patients with Psychosomatic Disorders.

    Directory of Open Access Journals (Sweden)

    Hubertus Sandler

    Full Text Available Vibroacoustic stimulation by a Body Monochord can induce relaxation states of various emotional valence. The skin conductance level (SCL of the tonic electrodermal activity is an indicator of sympathetic arousal of the autonomic nervous system and thus an indicator of the relaxation response. Salivary cortisol is considered to be a stress indicator of the HPA-axis. The effects of the treatment with a Body Monochord and listening to relaxation music (randomized chronological presentation on SCL and salivary cortisol in relation to the emotional valence of the experience were examined in patients with psychosomatic disorders (N = 42. Salivary cortisol samples were collected immediately before and after the expositions. Subjective experience was measured via self-rating scales. Overall, both the exposure to the Body Monochord as well as the exposure to the relaxation music induced an improvement of patients' mood and caused a highly significant reduction of SCL. A more emotionally positive experience of relaxation correlated with a slightly stronger reduction of the SCL. Both treatment conditions caused a slight increase in salivary cortisol, which was significant after exposure to the first treatment. The increase of salivary cortisol during a relaxation state is contrary to previous findings. It is possible that the relaxation state was experienced as an emotional challenge, due to inner images and uncommon sensations that might have occurred.

  8. pKI values of prazosin and idazoxan for receptors stimulated by neuronally released transmitter in the epididymal portion of rat isolated vas deferens.

    Science.gov (United States)

    Mackay, D; Kengatharan, M

    1994-01-01

    1. A new method has been used to measure pKI values of prazosin and idazoxan against neuronally-released transmitter in the epididymal portion of the rat isolated vas deferens. The most reproducible results were obtained with a prolonged antagonist equilibration time (1 h). 2. Under these conditions the pKI of prazosin was practically unaffected by addition of alpha, beta-methylene-adenosine-5'-triphosphate (10 microM) to desensitize purinoceptors. Addition of desmethylimipramine (DMI) (0.3 microM) produced a small, but statistically non-significant, reduction. 3. The same method has been used to measure the pKI of prazosin against exogenous noradrenaline. In the latter case addition of DMI (0.3 microM) and corticosterone (30 microM) together produced a statistically significant reduction in the apparent pKI of prazosin. 4. The new method for estimating pKI values shows that DMI itself acts either pseudo-irreversibly or non-competitively and may be reducing the apparent pKI of prazosin. 5. The pKI values obtained for prazosin and idazoxan against neuronally-released transmitter are in good agreement with those obtained by other workers for the actions of these drugs on alpha-adrenoceptors.

  9. Vibroacoustical analysis of rail vehicle

    Directory of Open Access Journals (Sweden)

    Králíček J.

    2007-11-01

    Full Text Available The article deals with the vibroacoustical analysis of rail vehicle and is the extension of the previously presented work “Modelování podvozku kolejového vozidla s poddajným rámem”. The vibroacoustical analysis uses the outcomes of the dynamical analysis of rail vehicle bogie i.e. surface velocities of the bogie frame to compute the acoustic power radiated by the bogie frame and forces acting in the bogie-body interface. The radiated power and the force spectra are then used as the excitation to the rail body model in the environment Auto-SEA to compute the interior acoustic quantities.

  10. Vibroacoustic: The challenges of a mission impossible?

    Science.gov (United States)

    Sestieri, Aldo; Carcaterra, Antonio

    2013-01-01

    Why it is difficult to solve a vibroacoustic problem; what are the hidden pitfalls that one is called to overcome; are there methods or techniques suggested in other fields of physics that can help to formulate an efficient vibroacoustic prediction model? The authors provide personal answers to these questions and suggest also a classification of the numerous prediction methods proposed in the literature.

  11. NASA's AVE/VAS program

    Science.gov (United States)

    Hill, C. K.; Turner, R. E.

    1983-01-01

    A discussion is presented concerning the Atmospheric Variability Experiment (AVE) which was conducted during the spring of 1982 as part of NASA's Visible and Infrared Spin-Scan Radiometer (VISSR) Atmospheric Sounder (VAS) demonstration. The AVE/VAS Ground Truth Field Experiment is examined in detail, which comprised the obtaining of rawinsonde observations during various meteorological conditions on four different days when VAS data were obtained. These experiments were performed over 24 hr periods in a mesoscale network of 24 National Weather Service rawinsonde sites and 13 NASA and NOAA special sites. The VAS, operating as a part of the GOES satellite system, was employed to provide two-dimensional cloud mapping capability during each of the AVE/VAS experiment periods. Among the goals of this AVE/VAS program, in addition to management of the acquisition and processing of the data, were to perform the research and development needed to produce data products from VAS radiances, to validate the data, and to assess the impact of the data on mesoscale meteorological forecasting and research requirements.

  12. Evaluation of the effectiveness of vibroacoustic therapy treatment of patients with so-called "heel spur". A preliminary report.

    Science.gov (United States)

    Łukasiak, Adam; Krystosiak, Monika; Widłak, Patrycja; Woldańska-Okońska, Marta

    2013-01-01

    The so-called "heel spur" is a radiological term referring to adaptive bone growth as a result of chronic overload enthesopathy of the proximal attachment of the plantar fascia. The main cause of the pain is continued localised pressure on the surrounding soft tissues. Vibroacoustic wave therapy is a relatively new method gaining popularity among doctors, physiotherapists and patients. The aim of this study was to confirm the clinical efficacy of vibroacoustic therapy compared to laser and ultrasound therapy. The study enrolled 60 patients treated for plantar heel spurs who were divided into a study group of 40 patients who underwent vibroacoustic therapy and a control group of 20 patients treated with ultrasound and laser therapy. The outcome measure for evaluating the effectiveness of physiotherapy was a subjective assessment of pain intensity by VAS and the modified short-form McGill Pain Questionnaire. The mean pain intensity score in patients undergoing vibroacoustic therapy decreased by about 2.6 points according to the VAS scale and 17 points according to the McGill questionnaire, compared to reductions of 0.6 and 6 points, respectively, in the ultrasound and laser therapy group. The correlation between subjective assessment of pain according to the VAS scale and palpation-based assessment of pain was significantly positive between the two groups, demonstrating similarity of the two scales, with a slight dominance of the group undergoing laser and ultrasound therapy. These results represent a tentative confirmation of analgesic effectiveness of the vibro-acoustic method in musculoskeletal overload conditions. 2. In order to confirm its effectiveness, it is necessary to conduct further prospective randomized studies with blinding and evaluate the long-term results.

  13. MR visualization of vas deferens

    Energy Technology Data Exchange (ETDEWEB)

    Manabe, Tomoko; Kaji, Yasushi; Maeda, Takaki; Kitamura, Yuri; Fujii, Masahiko; Sugimura, Kazuro [Kobe Univ. (Japan). School of Medicine

    2003-02-01

    The pelvic MRI studies of 140 male patients were reviewed to evaluate the extent of the depiction of the vas deferens. These MRI examinations were originally intended for the evaluation of other pelvic parts, and therefore the vas deferens was fully assessable in only 101 cases. For convenience, the vas deferens was divided into seven segments. A letter was then assigned to each segment, starting from the ampulla (A) to the internal inguinal canal (G). The depiction rates for the different segments were 100%, 96%, 82.2%, 76.2%, 64.4%, 54.5% and 43.6% for A through G respectively. The diameter of the vas deferens was also measured, yielding the following results: segment A=5.9{+-}1.4 mm, B=4.3{+-}1.1 mm, C=3.2{+-}0.9 mm, D=2.5{+-}0.8 mm, E=2.0{+-}0.6 mm, F=1.8{+-}0.8 mm, and G=1.6{+-}0.4 mm. There were no significant differences in age, underlying disease, and treatment of the patients in the study. When looking at the relationship between the diameter and the T{sub 2}-weighted signal intensity, we found that the larger the diameter the higher the signal. We assume from this that larger diameters reflect the internal liquid signal intensity, while small diameters seem to indicate the vas deferens wall signal intensity. We believe that MR imaging can depict the vas deferens in its physiological state. In this study however, it was not possible to evaluate this structure for abnormalities. If the resolution MR imaging increases, diagnosis concerning vas deferens may become possible. (author)

  14. Neurological aspects of vibroacoustic disease.

    Science.gov (United States)

    Martinho Pimenta, A J; Castelo Branco, N A

    1999-03-01

    Mood and behavioral abnormalities are the most common early findings related to vibroacoustic disease (VAD). Other signs and symptoms have been observed in VAD patients. Brain MRI discloses small multifocal lesions in about 50% of subjects with more than 10 yr of occupational exposure to large pressure amplitude (> or = 90 dB SPL) and low frequency (< or = 500 Hz) (LPALF) noise. However, to date, there have been no studies globally integrating all the neurological, imaging and neurophysiological data of VAD patients. This is the main goal of this study. The 60 male Caucasians diagnosed with VAD were neurologically evaluated in extreme detail in order to systematically identify the most common and significant neurological disturbances in VAD. This population demonstrates cognitive changes (identified through psychological and neurophysiological studies (ERP P300)), vertigo and auditory changes, visual impairment, epilepsy, and cerebrovascular diseases. Neurological examination reveals pathological signs and reflexes, most commonly the palmo-mental reflex. A vascular pattern underlying the multifocal hyperintensities in T2 MR imaging, with predominant involvement of the small arteries of the white matter, is probably the visible organic substratum of the neurological picture. However, other pathophyisological mechanisms are involved in epileptic symptomatology.

  15. Ares I-X Vibroacoustic Environments

    Science.gov (United States)

    Larsen, Curtis E.; Schuster, David M.; Kaufman, Daniel S.

    2009-01-01

    This paper provides a summary of the NASA Engineering and Safety Center (NESC) team recommendations and observations following participation with the Ares I-X Vibroacoustic (VA) Environments Panel in meetings at the Kennedy Space Center (KSC) and the Marshall Space Flight Center (MSFC) in March and April 2008, respectively.

  16. Selection of informative parameters of vibroacoustic processes

    Science.gov (United States)

    Koshek, L. N.

    1973-01-01

    The problem of selecting informative parameters of vibro-acoustic processes and the construction of apparatus for their determination are discussed. It is assumed that the processes being investigated are structurally uniform and either purely random or contain not very many determinative components.

  17. Vibroacoustic sound therapy improves pain management and more.

    Science.gov (United States)

    Boyd-Brewer, Chris; McCaffrey, Ruth

    2004-01-01

    Vibroacoustic therapy is a new sound technology that uses audible sound vibrations to reduce symptoms, invoke relaxation, and alleviate stress. This technology is developed based on the recognition that external vibration can influence body function. Research demonstrates the effectiveness of vibroacoustic therapy. Implications for nurses include investigating the possibilities of vibroacoustic therapy in various nursing settings to promote patient well-being and improve the therapeutic environment.

  18. Vibro-acoustics of lightweight sandwich structures

    CERN Document Server

    Lu, Tianjian

    2014-01-01

    Vibro-Acoustics of Lightweight Sandwich Structures introduces the study of the coupled vibration and acoustic behavior of lightweight sandwich structures in response to harmonic force and sound pressure. This book focuses on the theoretical modeling and experimental investigation of lightweight sandwich structures in order to provide a predictive framework for vibro-acoustic characteristics of typical engineering structures. Furthermore, by developing solution tools, it concentrates on the influence of key systematic parameters leading to effective guidance for optimal structure design toward lightweight, high-stiffness and superior sound insulation capability. This book is intended for researchers, scientists, engineers and graduate students in mechanical engineering especially in structural mechanics, mechanics and acoustics. Fengxian Xin and Tianjian Lu both work at the School of Aerospace, Xi’an Jiaotong University.

  19. The influence of vibroacoustic therapy on the functional status of patients with gonarthrosis. A preliminary report

    Directory of Open Access Journals (Sweden)

    Agnieszka Skopowska

    2014-11-01

    Full Text Available Aim of the study: Gonarthrosis is a degenerative disease of the articular cartilage. Its main symptoms are pain, swelling, stiffness, limitation of functions and deformations of the joint. One of the available methods of preservative treatment of gonarthrosis is vibroacoustic therapy (VT, which evokes micro-vibrations in the tissues – through the use of sound waves of variable frequency and amplitude. The aim of the study was to estimate the influence of VT on the functional status of people with gonarthrosis. Material and methods: Forty-four people, aged over 44, with gonarthrosis were subjected to 10 sessions of VT with the Vitafon-T device, in a variable range of frequencies between 30 and 18 000 Hz. The sessions lasted 15 minutes. In order to estimate the effectiveness of the therapy, double measurements (before and after therapy of the following parameters were taken: pain (VAS, joint circumferences and function tests (Timed Up and Go – TUG, the average free walking time at the 6 m distance and the knee bends test. The statistical analysis was carried out using the Wilcoxon test, with the significance level of p < 0.0001. Results : In the examined group a decrease was observed in: pain (by 1.9 VAS points among 77% of the patients, circumference of the joints among 91% and the time of conducting the TUG test in 96%. The number of knee bends increased in 82% of the patients. All the results reached statistical significance (p < 0.0001. The free walking improved among 91%; however, this result was not statistically significant. Conclusions : Vibroacoustic therapy has brought positive treatment effects of an analgesic and anti-swelling character, which has further influenced the functional efficiency of the patients with gonarthrosis. The research still needs to be expanded to other groups of patients before the method may be popularized in primary care rehabilitation facilities.

  20. The palmo-mental reflex in vibroacoustic disease.

    Science.gov (United States)

    Martinho Pimenta, A J; Castelo Branco, M S; Castelo Branco, N A

    1999-03-01

    Vibroacoustic disease (VAD), is a multisystemic nosological entity, caused by occupational exposure to large pressure amplitude (> or = 90 dB SPL) and low frequency (< or = 500 Hz) (LPALF) noise. The most common neurological finding in patients with VAD is the palmomental reflex (PMR). The aim of this study is to evaluate the frequency and characteristics of this primitive reflex in a population of VAD patients. Sixty individuals, occupationally exposed to LPALF noise underwent a neurological examination. In each one, unilateral contraction of the chin muscles was triggered through the stimulation of the thenar eminence. When a response habituation was observed, or when there was no response except previously existing skin retraction and small dimples, an EMG was performed. All these subjects also received brain MRI and measurement of endogenous evoked potentials. Thirty individuals presented unilateral or bilateral PMR; 26 of these presented changes in the brain MRI. EMG measurement evidenced continuous contraction of the chin muscles, without visible PMR, triggered by the stimulation of the thenar eminence. PMR is present in 50% of the patients with VAD. In the VAD patients, the frequency of abnormal chin muscle activity is higher than the frequency of PMR and represents a loss of the cortical control over the brainstem structures.

  1. Shuttle payload vibroacoustic test plan evaluation

    Science.gov (United States)

    Stahle, C. V.; Gongloff, H. R.; Young, J. P.; Keegan, W. B.

    1977-01-01

    Statistical decision theory is used to evaluate seven alternate vibro-acoustic test plans for Space Shuttle payloads; test plans include component, subassembly and payload testing and combinations of component and assembly testing. The optimum test levels and the expected cost are determined for each test plan. By including all of the direct cost associated with each test plan and the probabilistic costs due to ground test and flight failures, the test plans which minimize project cost are determined. The lowest cost approach eliminates component testing and maintains flight vibration reliability by performing subassembly tests at a relatively high acoustic level.

  2. Vibro-acoustic Imaging at the Breazeale Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Smith, James Arthur [Idaho National Lab. (INL), Idaho Falls, ID (United States); Jewell, James Keith [Idaho National Lab. (INL), Idaho Falls, ID (United States); Lee, James Edwin [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2016-09-01

    The INL is developing Vibro-acoustic imaging technology to characterize microstructure in fuels and materials in spent fuel pools and within reactor vessels. A vibro-acoustic development laboratory has been established at the INL. The progress in developing the vibro-acoustic technology at the INL is the focus of this report. A successful technology demonstration was performed in a working TRIGA research reactor. Vibro-acoustic imaging was performed in the reactor pool of the Breazeale reactor in late September of 2015. A confocal transducer driven at a nominal 3 MHz was used to collect the 60 kHz differential beat frequency induced in a spent TRIGA fuel rod and empty gamma tube located in the main reactor water pool. Data was collected and analyzed with the INLDAS data acquisition software using a short time Fourier transform.

  3. AVE/VAS experiment: Ground truth network

    Science.gov (United States)

    Scoggins, J. R.

    1983-01-01

    The visible/infrared spin scan radiometer (VISSR) atmospheric sounder (VAS) rawinsonde field program is discussed. Specific items covered include: planning, personnel requirements and training, operational requirement and procedures, sounding times and dates, methods of data processing, data inventory, and status of data processing.

  4. NuSTAR: Vibro-Acoustic Tests

    Energy Technology Data Exchange (ETDEWEB)

    Kasim, K.

    2004-09-03

    NuSTAR is a satellite that will be carrying X-ray optics that consist of many nested glass cylinders. Due to different acoustic environments, the glass may react such that cracks and/or fractures may form. Cracks and/or fractures in the glass would not allow the optic to work properly. Therefore, it is necessary to test the glass and optic prototypes to determine if they will be able to withhold when experiencing certain acoustic environments. The vibro-acoustic testing conducted at the Jet Propulsion Laboratory (JPL) in Pasadena determined that under the minimum workmanship acoustic environments, the glass on the optics will not fail. Overall, the results of the test were successful which gives confidence that when the satellite is launched into the air and then dropped into space, the glass in the optics will not fail.

  5. Aero and vibroacoustics of automotive turbochargers

    CERN Document Server

    Nguyen-Schäfer, Hung

    2013-01-01

    Aero and Vibroacoustics of Automotive Turbochargers is a topic involving aspects from the working fields of thermodynamics of turbomachinery, aerodynamics, rotordynamics, and noise propagation computation.   In this broadly interdisciplinary subject, thermodynamics of turbomachinery is used to design the turbocharger and to determine its operating conditions.  Aerodynamics is needed to study the compressor flow dynamics and flow instabilities of rotating stall and surge, which can produce growling and whining-type noises. Rotordynamics is necessary to study rotor unbalance and self-excited oil-whirl instabilities, which lead to whistling and constant tone-type noises in rotating floating oil-film type bearings. For the special case of turbochargers using ball bearings, some high-order harmonic and wear noises also manifest in the rotor operating range. Lastly, noise propagation computation, based on Lighthill’s analogy, is required to investigate airborne noises produced by turbochargers in passenger vehi...

  6. Shuttle payload minimum cost vibroacoustic tests

    Science.gov (United States)

    Stahle, C. V.; Gongloff, H. R.; Young, J. P.; Keegan, W. B.

    1977-01-01

    This paper is directed toward the development of the methodology needed to evaluate cost effective vibroacoustic test plans for Shuttle Spacelab payloads. Statistical decision theory is used to quantitatively evaluate seven alternate test plans by deriving optimum test levels and the expected cost for each multiple mission payload considered. The results indicate that minimum costs can vary by as much as $6 million for the various test plans. The lowest cost approach eliminates component testing and maintains flight vibration reliability by performing subassembly tests at a relatively high acoustic level. Test plans using system testing or combinations of component and assembly level testing are attractive alternatives. Component testing alone is shown not to be cost effective.

  7. Feasibility of using vibroacoustic monitoring for assessment of technical condition of hoist drives

    Energy Technology Data Exchange (ETDEWEB)

    Spalek, J.; Fober, S. (Politechnika Slaska, Gliwice (Poland). Instytut Mechanizacji Gornictwa)

    1990-01-01

    Analyzes use of vibroacoustic testing of gears for hoists used in underground coal mining. Accuracy of vibroacoustic testing is evaluated on the example of 4 hoists used in the Katowice black coal mine (in a main hoisting shaft, in an auxiliary shaft and in 2 blind shafts). Types of electric motors, their rated power and types of gears are compared. Effects of wear on vibroacoustic emission are analyzed. Design and use of a system for measuring vibroacoustic emission of gears are described. Measurement results are evaluated. Effects of damping mechanical vibrations and acoustic emission by individual elements of the mechanical transmissions on reliability and accuracy of vibroacoustic testing are analyzed. 10 refs.

  8. Energy Harvesting with Piezoelectric Element Using Vibroacoustic Coupling Phenomenon

    Directory of Open Access Journals (Sweden)

    Hiroyuki Moriyama

    2013-01-01

    Full Text Available This paper describes the vibroacoustic coupling between the structural vibrations and internal sound fields of thin structures. In this study, a cylindrical structure with thin end plates is subjected to the harmonic point force at one end plate or both end plates, and a natural frequency of the end plates is selected as the forcing frequency. The resulting vibroacoustic coupling is then analyzed theoretically and experimentally by considering the dynamic behavior of the plates and the acoustic characteristics of the internal sound field as a function of the cylinder length. The length and phase difference between the plate vibrations, which maximize the sound pressure level inside the cavity, are clarified theoretically. The theoretical results are validated experimentally through an excitation experiment using an experimental apparatus that emulates the analytical model. Moreover, the electricity generation experiment verifies that sufficient vibroacoustic coupling can be created for the adopted electricity generating system to be effective as an electric energy-harvesting device.

  9. Vibroacoustic test plan evaluation: Parameter variation study

    Science.gov (United States)

    Stahle, C. V.; Gongloef, H. R.

    1976-01-01

    Statistical decision models are shown to provide a viable method of evaluating the cost effectiveness of alternate vibroacoustic test plans and the associated test levels. The methodology developed provides a major step toward the development of a realistic tool to quantitatively tailor test programs to specific payloads. Testing is considered at the no test, component, subassembly, or system level of assembly. Component redundancy and partial loss of flight data are considered. Most and probabilistic costs are considered, and incipient failures resulting from ground tests are treated. Optimums defining both component and assembly test levels are indicated for the modified test plans considered. modeling simplifications must be considered in interpreting the results relative to a particular payload. New parameters introduced were a no test option, flight by flight failure probabilities, and a cost to design components for higher vibration requirements. Parameters varied were the shuttle payload bay internal acoustic environment, the STS launch cost, the component retest/repair cost, and the amount of redundancy in the housekeeping section of the payload reliability model.

  10. Music and Vibroacoustic Stimulation in People with Rett Syndrome

    DEFF Research Database (Denmark)

    Bergström-Isacsson, Märith

    2011-01-01

    Background: Rett syndrome (RTT) is a neurodevelopmental disorder which affects basic body functions including the central control of the autonomic nervous system in the brainstem. Music is used by parents and carers in different situations, e.g. to calm down, to activate, to motivate...... and in communication. The aim of the study was to examine what effect musical stimuli had on the control functions of the autonomic nervous system, and on cortical emotional reactions, in participants with RTT. Methods: The study included 35 participants with RTT who were referred to the Swedish Rett Center...... emotions and ambiguous responses. These expressions were then related to results from brainstem assessment and the music used. Results: Continuous responses showed that Calming and VT increased CVT significantly in the RTT group. Horn elicited a similar response in both groups (decrease in CSB, indicating...

  11. Vibroacoustic Model Validation for a Curved Honeycomb Composite Panel

    Science.gov (United States)

    Buehrle, Ralph D.; Robinson, Jay H.; Grosveld, Ferdinand W.

    2001-01-01

    Finite element and boundary element models are developed to investigate the vibroacoustic response of a curved honeycomb composite sidewall panel. Results from vibroacoustic tests conducted in the NASA Langley Structural Acoustic Loads and Transmission facility are used to validate the numerical predictions. The sidewall panel is constructed from a flexible honeycomb core sandwiched between carbon fiber reinforced composite laminate face sheets. This type of construction is being used in the development of an all-composite aircraft fuselage. In contrast to conventional rib-stiffened aircraft fuselage structures, the composite panel has nominally uniform thickness resulting in a uniform distribution of mass and stiffness. Due to differences in the mass and stiffness distribution, the noise transmission mechanisms for the composite panel are expected to be substantially different from those of a conventional rib-stiffened structure. The development of accurate vibroacoustic models will aide in the understanding of the dominant noise transmission mechanisms and enable optimization studies to be performed that will determine the most beneficial noise control treatments. Finite element and boundary element models of the sidewall panel are described. Vibroacoustic response predictions are presented for forced vibration input and the results are compared with experimental data.

  12. Vibro-acoustics of porous materials - waveguide modeling approach

    DEFF Research Database (Denmark)

    Darula, Radoslav; Sorokin, Sergey V.

    2016-01-01

    The porous material is considered as a compound multi-layered waveguide (i.e. a fluid layer surrounded with elastic layers) with traction free boundary conditions. The attenuation of the vibro-acoustic waves in such a material is assessed. This approach is compared with a conventional Biot's model...

  13. Velocity measurement by vibro-acoustic Doppler.

    Science.gov (United States)

    Nabavizadeh, Alireza; Urban, Matthew W; Kinnick, Randall R; Fatemi, Mostafa

    2012-04-01

    We describe the theoretical principles of a new Doppler method, which uses the acoustic response of a moving object to a highly localized dynamic radiation force of the ultrasound field to calculate the velocity of the moving object according to Doppler frequency shift. This method, named vibro-acoustic Doppler (VAD), employs two ultrasound beams separated by a slight frequency difference, Δf, transmitting in an X-focal configuration. Both ultrasound beams experience a frequency shift because of the moving objects and their interaction at the joint focal zone produces an acoustic frequency shift occurring around the low-frequency (Δf) acoustic emission signal. The acoustic emission field resulting from the vibration of the moving object is detected and used to calculate its velocity. We report the formula that describes the relation between Doppler frequency shift of the emitted acoustic field and the velocity of the moving object. To verify the theory, we used a string phantom. We also tested our method by measuring fluid velocity in a tube. The results show that the error calculated for both string and fluid velocities is less than 9.1%. Our theory shows that in the worst case, the error is 0.54% for a 25° angle variation for the VAD method compared with an error of -82.6% for a 25° angle variation for a conventional continuous wave Doppler method. An advantage of this method is that, unlike conventional Doppler, it is not sensitive to angles between the ultrasound beams and direction of motion.

  14. AVE/VAS experiment: Synoptic summary and preliminary results

    Science.gov (United States)

    Jedlovec, G. J.

    1983-01-01

    The AVE/VAS ground truth field experiment was conducted during the Spring of 1982 severe storms and weather research program. The experiment consisted of acquiring correlative ground truth measurements of rawinsonde data, corresponding to the time and space resolutions of VAS sounding data. The objectives of the AVE/VAS experiment are: (1) to acquire four dimensional data sets of the actual atmospheric structure down to the mesoscale; (2) to provide measurements for quantitative comparisons between ground based and VAS-derived atmospheric parameters; (3) to evaluate the impact of VAS data on diagnostic analysis of structural features and dynamical processes important to the development of mesoscale phenomena; (4) to evaluate the impact of VAS data on numerical model simulations, nowcasting, and other mesoscale forecasting systems.

  15. Noninvasive laser coagulation of the canine vas deferens, in vivo

    Science.gov (United States)

    Cilip, Christopher M.; Ross, Ashley E.; Jarow, Jonathan P.; Fried, Nathaniel M.

    2010-02-01

    Development of a noninvasive vasectomy technique may eliminate male fear of complications (incision, bleeding, infection, and scrotal pain) and result in a more popular procedure. This study builds upon previously reported ex vivo tissue studies by exploring acute and short-term chronic in vivo canine studies. Isolation of the canine vas was achieved using a conventional vas ring clamp method. No perforation of the scrotal skin was necessary to occlude the vas. Laser radiation with a wavelength of 1075 nm, average power of 11.2 W, 500-ms pulse duration, 0.5 Hz pulse rate, and 3-mm-diameter spot was synchronized with cryogen spray cooling of the scrotal skin surface in a total of 8 dogs (n = 16 vasa) for a treatment time of 60 s. Burst pressure measurements were conducted at Days 0 and 21 (n = 8 vasa each day) to quantify the strength of vas closure. The vas was successfully thermally occluded in 15/16 (94%) procedures with 14/15 (93%) vas recording burst pressures above ejaculation pressure. One vas was not present, and another vas recorded a bursting pressure below ejaculation pressure. The coagulated vas bursting pressure averaged 283 +/- 34 mm Hg at Day 0 and 260 +/- 77 mm Hg at Day 21, significantly higher than reported vas ejaculation pressures of 136 +/- 29 mm Hg. Minor scrotal skin burns were observed during the recovery period. Noninvasive thermal occlusion of the vas is feasible in an in vivo canine model. Elimination of minor skin burns and longer term chronic in vivo canine studies are needed to confirm azospermia after vas occlusion without recanalization.

  16. Abnormal respiratory drive in vibroacoustic disease.

    Science.gov (United States)

    Ferreira, João Reis; Albuquerque e Sousa, José; Foreld, Peter; Antunes, Marco; Cardoso, Sofia; Alves-Pereira, Mariana; Castelo Branco, Nuno A A

    2006-01-01

    Central nervous system disorders in workers exposed to low frequency noise (LFN, vibroacoustic disease (VAD) is defined as the systemic pathology caused by excessive exposure to LFN. The respiratory tract continues to be under heavy scrutiny in both LFN-exposed humans and animal models and has been confirmed as a major target for LFN-induced damage. Given that both the respiratory and central nervous systems were compromised in these workers, it became pertinent to investigate the status of the neurological control of breathing in VAD patients. The P- 0.1 value, a measure of the suction pressure developed at the mouth 0.1 seconds after the start of inspiration, depends on the respiratory centres and the autonomic nervous system pathway of the neural control of respiratory function. By rebreathing CO2, (6% in air) normal individuals present an average seven-fold increase in P0.1 (CO2) as compared to basal P- 0.1. Twenty-two male VAD patients (ave. age 50.5 +/- 8.5 years, range: 36-66 years) underwent the P0.1(CO2) index respiratory drive tests, as well as standard pulmonary function tests. Seven individuals (ave. age 42.4 +/-14 years, range: 25- 61 years) with reduced LFN exposure served as controls. Pulmonary function tests were normal in both VAD patients and controls. The P0.1 (CO2) in- dex was below average value in VAD patients (average: 22.9%) while it presented normal values in the control group (average > 60%). In the involuntary response to increased PCO2 levels, central chemoreceptors are responsible for 70% of the ventilatory stimulus. In VAD patients, this dysfunction may originate in the brainstem. This is corroborated by the fact that VAD patients register abnormal values for auditory brainstem evoked potentials, and disclose lesions with magnetic resonance imaging. The neurological control of breathing is compromised in VAD patients. The P0.1 (CO2) index may be a useful clinical indicator for VAD diagnosis and follow-up.

  17. Respiratory squamous cell carcinomas in vibroacoustic disease.

    Science.gov (United States)

    Reis Ferreira, José; Mendes, Carla P; Alves-Pereira, Mariana; Castelo Branco, Nuno A A

    2006-01-01

    In 1987, the autopsy of a vibroacoustic disease (VAD) patient disclosed two tumours: a renal cell carcinoma and a malignant glioma in the brain. Since 1987, malignancy in VAD patients has been under close surveillance. To date, in a universe of 945 individuals, there are 46 cases of malignancies, of which 11 are multiple. Of the 11 cases of respiratory tract tumours, all were squamous cell carcinomas (SqCC). This report focuses on the morphological features of these tumours. Tumour fragments were collected (endoscopic biopsy or surgery) from 11 male VAD patients (ave. age: 58+/-9 years, 3 non-smokers): 2 in glottis and 9 in the lung. In the 3 non-smokers, 2 had lung tumours and 1 had a glottis tumour. All were employed as or retired aircraft technicians, military or commercial pilots. Fragments were fixed either for light and electron microscopy. Immunohistochemistry studies used chromagranine and synaptophysine staining. All lung tumours were located in the upper right lobe bronchi and were histologically poorly differentiated SqCC (Figs. 1, 2). The search with neuroendocrine markers was negative. The average age of tumour onset in helicopter pilots was below 50 years old while for the other professional groups it was above 50. Nine patients are deceased. The 2 surviving patients are heavy smokers (> 2 packs/day). Smoking habits had no influence on tumour outcome and progression. Epidemiological studies indicate that squamous cell carcinomas account for approximately 40% of all lung tumours in men. It seems to be highly relevant that all VAD patient respiratory tract tumours are squamous cell carcinomas. It is not surprising that helicopter pilots are the ones who are affected the earliest because previous studies have shown that helicopter pilots exhibited the highest values for the frequency of sister chromatid exchanges. Generally, epidemiological tumor studies do not take histological tumor type into account, but given the results herein, it would seem of the

  18. Vibroacoustic testing of gear transmissions for hoist drives

    Energy Technology Data Exchange (ETDEWEB)

    Antoniak, J.; Spalek, J. (Politechnika Slaska, Gliwice (Poland). Instytut Mechanizacji Gornictwa)

    1990-01-01

    The drive system of a hoist used in the Knurow black coal mine in Poland was investigated using vibroacoustic testing. The system consisted of 2 electric motors each with a power of 1,300 kW (600 r.p.m.) and the GCD-17 gear transmission. Vibrations and acoustic emission generated by individual elements of the mechanical transmission (roller bearings, gear wheels etc.) are evaluated. Design and operation of a measuring system, site selection of measuring points, frequency range of vibrations generated by the bearings or gears are analyzed. Examples of vibration spectra are evaluated. Recommendations for use of vibroacoustic testing in diagnostics of heavy-duty mining equipment are made. 3 refs.

  19. Comparison of the vibroacoustical characteristics of different pianos

    CERN Document Server

    Boutillon, Xavier; Paulello, Stephen

    2012-01-01

    On the basis of a recently proposed vibro-acoustical model of the piano soundboard (X. Boutillon and K. Ege, Vibroacoustics of the piano soundboard: reduced models, mobility synthesis, and acoustical radiation regime. \\emph{submitted to the Journal of Sound and Vibration}, 2011.), we present several models for the coupling between the bridge and the ribbed plate of the soundboard. The models predict the modal density and the characteristic impedance at the bridge as a function of the frequency. Without parameter adjustment, the sub-structure model turns out to fit the experimental data with an excellent precision. The influence of the elastic parameters of wood is discussed. The model predictions are compared for pianos of different sizes and types.

  20. Vibroacoustic Analysis of Large Heat Rejection Radiators for Future Spacecraft

    Science.gov (United States)

    Larko, Jeffrey M.; McNelis, Mark E.; Hughes, William O.

    2006-01-01

    Spacecraft structures such as antennas, solar arrays and radiator panels significantly respond to high acoustic levels seen at lift-off. Some future spacecraft may utilize nuclear electric propulsion that require large radiator panels to reject waste heat. A vibroacoustic assessment was performed for two different radiator panel designs. Results from the analysis of the two designs using different analytical approaches are presented and discussed.

  1. Vibro-acoustic modulation–based damage identification in a composite skin–stiffener structure

    NARCIS (Netherlands)

    Ooijevaar, T.H.; Rogge, M.D.; Loendersloot, Richard; Warnet, Laurent; Akkerman, Remko; Tinga, Tiedo

    2016-01-01

    Vibro-acoustic modulation–based damage identification relies on the modulation of a high-frequency carrier signal by an intenser low-frequency vibration signal due to damage-induced structural nonlinearities. A time domain analysis of the vibro-acoustic modulation phenomena was presented at multiple

  2. Experimental studies of the vibroacoustic characteristics of a large-scale energy pump

    Energy Technology Data Exchange (ETDEWEB)

    Gaev, G.P.; Kail, I.I.; Kinski, D.; Koban, I.; Zhileiko, P.G.

    1986-06-01

    The results are given from experimental studies of the vibroacoustic characteristics of a large-scale energy (velocity) pump for the purpose of diagnosing its state under various service operating conditions. Recommendations are given for measuring the statistical characteristics of vibroacoustic pump noise.

  3. Effects of Vibroacoustic Music on Challenging Behaviors in Individuals with Autism and Developmental Disabilities

    Science.gov (United States)

    Lundqvist, Lars-Olov; Andersson, Gunilla; Viding, Jane

    2009-01-01

    Vibroacoustic music has been proposed to be an effective treatment for individuals with developmental disorders and challenging behaviors. The present study experimentally tested the effects of vibroacoustic music on self-injurious, stereotypical, and aggressive destructive behaviors in 20 individuals with autism spectrum disorders and…

  4. Application of the Bootstrap Statistical Method in Deriving Vibroacoustic Specifications

    Science.gov (United States)

    Hughes, William O.; Paez, Thomas L.

    2006-01-01

    This paper discusses the Bootstrap Method for specification of vibroacoustic test specifications. Vibroacoustic test specifications are necessary to properly accept or qualify a spacecraft and its components for the expected acoustic, random vibration and shock environments seen on an expendable launch vehicle. Traditionally, NASA and the U.S. Air Force have employed methods of Normal Tolerance Limits to derive these test levels based upon the amount of data available, and the probability and confidence levels desired. The Normal Tolerance Limit method contains inherent assumptions about the distribution of the data. The Bootstrap is a distribution-free statistical subsampling method which uses the measured data themselves to establish estimates of statistical measures of random sources. This is achieved through the computation of large numbers of Bootstrap replicates of a data measure of interest and the use of these replicates to derive test levels consistent with the probability and confidence desired. The comparison of the results of these two methods is illustrated via an example utilizing actual spacecraft vibroacoustic data.

  5. An Approximate Analytical Method of the Nonlinear Vibroacoustic Coupling System

    Directory of Open Access Journals (Sweden)

    Qizheng Zhou

    2014-01-01

    Full Text Available An approximate analytical method of the nonlinear vibroacoustic coupling system is proposed for the first time. Taking the Duffing oscillator-plate-medium system as an example, the nonlinear vibroacoustic coupling equations are developed using variational principle. The two major difficulties which lie in solving the coupling equations are the uncertain motion of the oscillator and the surface acoustic pressure on the plate, a system for which the fluid-structure coupling cannot be neglected. Based on the incremental harmonic balance (IHB method, the motion of the oscillator is expressed in the form of the Fourier series, and then the modal expression method and the incoherent assumption are employed to discretize the displacement and the surface pressure of the plate. Then the approximate analytical solution is given by the IHB method. The characteristics of acoustic radiation and surface quadratic velocity of the plate, the nonlinear characteristics of oscillator, and the influence of the excitation frequency and the nonlinear stiffness on the results are investigated by the numerical simulation. The results show that the excitation at the frequency close to the natural frequency of the oscillator can produce a significant response of the third-harmonic generation which determines the vibroacoustic characteristics of the plate.

  6. Filtration of sunflower oil in the field of vibroacoustic effects

    Directory of Open Access Journals (Sweden)

    S. A. Bredikhin

    2017-01-01

    Full Text Available Purification of crude unrefined sunflower oil along with the removal of primary oxidation products is an urgent task to remove the solid constituents formed during the processing of sunflower seeds. All of them irrespective of the chemical composition negatively affect the quality of the food product and, over time, saturate the oil with coagulants that affect its organoleptic and physico-mechanical characteristics. The problem of cleaning unrefined sunflower oil by filtration with the use of vibroacoustic action is considered. The calculation scheme of the process is given, and an experimental setup has been developed that makes it possible to vary the angle of inclination of the filter element. The research of sunflower oil filtration in the field of vibroacoustic impact is carried out. In the study, a decision was made to expand the energy effects to create a cumulative system in the liquid medium that improves the hydrodynamic situation at the scale of the oil purification plant. It is established that the process speed can be intensified by creating additional microflows that provide an active influence on the motion of liquid, gas and solid particles. The results are obtained, which testify to the effectiveness of the use of vibroacoustic effects during the filtration of sunflower oil.

  7. Ureteral Obstruction by the Vas Deferens after Urostomy

    Directory of Open Access Journals (Sweden)

    Subramanian Vaidyanathan

    2010-01-01

    Full Text Available A male patient with spina bifida and paraplegia, born in 1968, underwent urostomy in 1973. In 1999, he developed urine infections. Intravenous urography showed bilateral hydronephrosis and hydroureter. This patient continued to get recurrent urine infections. In 2009, computed tomography of the abdomen revealed dilatation of the ureters, but the ureters reverted to normal calibre as they passed forward through the anterior abdominal wall. The vas deferens on either side was crossing and kinking the ureter. Magnetic resonance imaging of the abdomen confirmed that the level of obstruction in both ureters was at the site where the vas deferens crossed the ureter and kinked it. While performing urostomy, the ureters below the crossover by the vas deferens were detached from the bladder and attached to the skin for urinary diversion, thus causing the vas deferens to hook the lower end of the ureters. As the patient gained height and weight, thereby increasing abdominal girth, kinking of the ureters by the vas deferens was accentuated. In hindsight, bilateral midline cutaneous urostomy using the ureters below the crossover by the vas deferens represents a poor surgical technique for urinary diversion.

  8. A Vibroacoustic Database Management Center for Shuttle and expendable launch vehicle payloads

    Science.gov (United States)

    Thomas, Valerie C.

    1987-01-01

    A Vibroacoustic Database Management Center has recently been established at the Jet Propulsion Laboratory (JPL). The center uses the Vibroacoustic Payload Environment Prediction System (VAPEPS) computer program to maintain a database of flight and ground-test data and structural parameters for both Shuttle and expendable launch-vehicle payloads. Given the launch-vehicle environment, the VAPEPS prediction software, which employs Statistical Energy Analysis (SEA) methods, can be used with or without the database to establish the vibroacoustic environment for new payload components. This paper summarizes the VAPEPS program and describes the functions of the Database Management Center at JPL.

  9. Parametric evaluation of the cost effectiveness of Shuttle payload vibroacoustic test plans

    Science.gov (United States)

    Stahle, C. V.; Gongloff, H. R.; Keegan, W. B.; Young, J. P.

    1978-01-01

    Consideration is given to alternate vibroacoustic test plans for sortie and free flyer Shuttle payloads. Statistical decision models for nine test plans provide a viable method of evaluating the cost effectiveness of alternate vibroacoustic test plans and the associated test levels. The methodology is a major step toward the development of a useful tool for the quantitative tailoring of vibroacoustic test programs to sortie and free flyer payloads. A broader application of the methodology is now possible by the use of the OCTAVE computer code.

  10. Damage imaging in nonlinear vibro-acoustic modulation tests

    Science.gov (United States)

    Pieczonka, Lukasz; Klepka, Andrzej; Uhl, Tadeusz; Staszewski, Wieslaw J.

    2015-03-01

    The paper deals with the nonlinear vibro-acoustic modulation technique (VAM) used for nondestructive damage detection in composites. In its original form the technique allows only for the determination of the presence of damage in a structure. This paper presents an enhancement of the technique that allows also for the determination of damage location. Experimental testing of the proposed procedure is performed on carbon fiber/epoxy laminated composite plates with barely visible impact damage that was generated in an impact test. Shearography was used to verify damage location. Piezoceramic actuators are used for vibration excitation and a scanning laser vibrometer is used for data acquisition.

  11. Mechanical modelling and application of vibroacoustic isolators in railway tracks

    Directory of Open Access Journals (Sweden)

    Zbiciak Artur

    2017-01-01

    Full Text Available The paper presents systematization and description of vibroacoustic isolators used in railway tracks (due to track structure type, with special attention paid to resilient mats. As in the second part of the paper the state-space mechanical model of a system with Under-Ballast Mat is formulated. Also some numerical problems arising from the mass matrix singularity are discussed. The poles of the system were calculated by using Matlab. Moreover, the influence of various parameters on the system’s insertion loss and its transmissibility was visualized in figures.

  12. Effects of in vitro, acute and chronic treatment with fluoxetine on the sympathetic neurotransmission of rat vas deferens.

    Science.gov (United States)

    Pedroso, Shaista Poppe; de Souza, Bruno Palmieri; Jurkiewicz, Aron; Juriewicz, Neide H; da Silva Junior, Edilson Dantas

    2017-03-01

    It is described that fluoxetine treatment is able to induce ejaculatory disorders. However, the exact mechanism is still not fully understood. Therefore, this study was carried out to further evaluate the anti-ejaculatory effects of fluoxetine, using different approaches (in vitro or in vivo treatments), on the sympathetic neurotransmission of the rat vas deferens. Vas deferens from male Wistar rats were used to check the in vitro effects of fluoxetine 10(-6)M, 3.10(-6)M or 10(-5)M. Animals were also acutely (20mg/kg, i.p. 4h or 24h) or chronically (10mg/kg, i.p., 30days) treated with fluoxetine or drug-free vehicle. The vas deferens from non-treated and treated animals were isolated and mounted in an isolated organ bath for the study of the contractions induced by adrenergic agonists, tyramine, 5-HT, Ca(2+) or electrical field stimulation. In vitro or acute treatment with fluoxetine decreased the contraction induced by agonists, Ca(2+) or electrical field stimulation. The chronic treatment with fluoxetine decreased the contractions induced agonists, tyramine or Ca(2+), but did not modify the contractions induced by electrical field stimulation. We have shown that in vitro or in vivo fluoxetine treatment is able to alter the sympathetic neurotransmission of the rat vas deferens which could be related to alterations in the calcium signalling. Copyright © 2016 Elsevier B.V. All rights reserved.

  13. A case of congenital unilateral absence of the vas deferens

    Directory of Open Access Journals (Sweden)

    Mo B

    2013-04-01

    Full Text Available Bi Mo,1 Vishnu Garla,2 Lawrence M Wyner1 1Department of Surgery, 2Department of Internal Medicine, Marshall University, Huntington, WV, USA Background: Congenital unilateral absence of the vas deferens occurs in 0.5%–1.0% of males. It has been associated with various genitourinary abnormalities, including renal agenesis. We report a case of congenital unilateral absence of the vas deferens found incidentally during vasectomy in a patient with known unilateral renal agenesis. Case presentation: A 24-year-old male presented to our urology clinic requesting vasectomy. His past history was significant for left renal agenesis. Following successful right vasectomy, several attempts to locate the left vas deferens were unsuccessful. We diagnosed congenital unilateral absence of the vas deferens. Follow-up semen analysis showed azoospermia. Conclusion: As vasectomies are increasingly performed in outpatient settings, it is imperative that physicians be aware of this condition, which can be recognized by a simple physical exam. Recognition could prevent unnecessary surgery and prompt providers to investigate for associated abnormalities. Keywords: vas deferens, embryology, abnormalities, surgery

  14. Global sensitivity analysis of analytical vibroacoustic transmission models

    Science.gov (United States)

    Christen, Jean-Loup; Ichchou, Mohamed; Troclet, Bernard; Bareille, Olivier; Ouisse, Morvan

    2016-04-01

    Noise reduction issues arise in many engineering problems. One typical vibroacoustic problem is the transmission loss (TL) optimisation and control. The TL depends mainly on the mechanical parameters of the considered media. At early stages of the design, such parameters are not well known. Decision making tools are therefore needed to tackle this issue. In this paper, we consider the use of the Fourier Amplitude Sensitivity Test (FAST) for the analysis of the impact of mechanical parameters on features of interest. FAST is implemented with several structural configurations. FAST method is used to estimate the relative influence of the model parameters while assuming some uncertainty or variability on their values. The method offers a way to synthesize the results of a multiparametric analysis with large variability. Results are presented for transmission loss of isotropic, orthotropic and sandwich plates excited by a diffuse field on one side. Qualitative trends found to agree with the physical expectation. Design rules can then be set up for vibroacoustic indicators. The case of a sandwich plate is taken as an example of the use of this method inside an optimisation process and for uncertainty quantification.

  15. Pointers, Lessons Learned, and Rules of Thumb for Successful Vibro-Acoustic Data Acquisition

    Science.gov (United States)

    Rossoni, Peter

    1998-01-01

    This presentation contains helpful pointers for successful vibroacoustic data acquisition in the following three areas: Instrumentation, Vibration Control and Pyro-shock data acquisition and analysis. A helpful bibliography is provided.

  16. Vides riski Daugavgrīvas dabas liegumā

    OpenAIRE

    Deinate, Elīna

    2014-01-01

    Bakalaura darbā „Vides riski Daugavgrīvas daba liegumā” ir pētīti pašreizējie un potenciālie vides riski Daugavgrīvas dabas liegumā. Vislielākā uzmanība tiek veltīta dabas lieguma piekrastē notiekošo krasta procesu raksturam, to ietekme uz dabas liegumu. Pētījuma ietvaros tiek analizētas krasta līnijas izmaiņas Daugavgrīvas salā izmantojot kartogrāfisko materiālu un jūras krasta ģeoloģisko procesu monitoringa datus. Pētījuma rezultātā tiek veikti secinājumi par dabas lieguma teritorijas iespē...

  17. A Method of Abnormal States Detection Based on Adaptive Extraction of Transformer Vibro-Acoustic Signals

    Directory of Open Access Journals (Sweden)

    Liang Zou

    2017-12-01

    Full Text Available State monitoring is very important for the safe operation of high-voltage transformers. A non-contact vibro-acoustic detection method based on the Blind Source Separation (BSS was proposed in this paper to promote the development of transformer on-line monitoring technology. Firstly, the algorithm of Sparse Component Analysis (SCA was applied for the adaptive extraction of vibro-acoustic signals, which utilizes the sorted local maximum values of the potential function. Then, the operating states of the transformer were detected by analyzing the vibro-acoustic signal eigenvectors. Different conditions including running normally, increasing of transformer vibro-acoustic amplitude and changing of frequency component of transformer vibro-acoustic were simulated. Moreover, experiments were carried out in a 220 kV substation. The research results show that the number of mixed noise sources can be estimated and the transformer vibro-acoustic signal was always ranked first in the separation signals. The source signals were effectively separated from the mixed signals while all of the correlation coefficients are more than 0.98 and the quadratic residuals are less than −32 dB. As for the experiments, the vibro-acoustic signal was separated out successfully from two voice signals and two interference signals. The acoustic signal reflection is considered as the main cause of the signal interference, and the transformer volume source model is considered as the main reason of unstable vibro-acoustic signal amplitude. Finally, the simulated abnormal states of the transformer were well recognized and the state of the tested transformer was judged to be normal.

  18. Research activities on vibro-acoustics of satellites during rocket launch

    OpenAIRE

    Murakami, Keiichi; Inada, Yoshinobu; Aoyama, Takashi; Takahashi, Takashi; Aiso, Hideaki; 村上 桂一; 稲田 喜信; 青山 剛史; 高橋 孝; 相曽 秀昭

    2006-01-01

    A study to establish a prediction method for vibro-acoustics of satellites during rocket launch has been conducted using a multidisciplinary analysis method of fluid, acoustic, and vibration. This coupling method consists of following four elements: numerical analyses of (1) sound generation, (2) sound propagation, (3) sound permeation, and (4) vibro-acoustics of payload. In the sound generation analysis, it can be seen from FEM analysis of a simply modeled deflector that a strong resonance o...

  19. Transverse testicular ectopia with a blind ending vas deferens

    Directory of Open Access Journals (Sweden)

    Anjan Kumar Dhua

    2016-01-01

    Full Text Available Transverse testicular ectopia (TTE is an uncommon anomaly of testicular descent. Herein, we describe a case of TTE with blindly ending vas and persistent Mόllerian duct syndrome in a 2-year-old child. Orchidopexy could be done through the normal orthotopic route after separating it from the Mόllerian structure and dividing the peritoneal fold just distal to the blindly ending vas. The report highlights that laparoscopy is useful for identifying subtle anomalies in addition to its therapeutic role.

  20. Exploration of Terminal Procedures Enabled by NASA Wake VAS Technologies

    Science.gov (United States)

    Lunsford, Clark R.; Smith, Arthur P., III; Cooper, Wayne W., Jr.; Mundra, Anand D.; Gross, Amy E.; Audenaerd, Laurence F.; Killian, Bruce E.

    2004-01-01

    The National Aeronautics and Space Administration (NASA) tasked The MITRE Corporation's Center for Advanced Aviation System Development (CAASD) to investigate potential air traffic control (ATC) procedures that could benefit from technology used or developed in NASA's Wake Vortex Advisory System (WakeVAS). The task also required developing an estimate of the potential benefits of the candidate procedures. The main thrust of the investigation was to evaluate opportunities for improved capacity and efficiency in airport arrival and departure operations. Other procedures that would provide safety enhancements were also considered. The purpose of this investigation was to provide input to the WakeVAS program office regarding the most promising areas of development for the program. A two-fold perspective was desired: First, identification of benefits from possible procedures enabled by both incremental components and the mature state of WakeVAS technology; second identification of procedures that could be expected to evolve from the current Federal Aviation Administration (FAA) procedures. The evolution of procedures should provide meaningful increments of benefit and a low risk implementation of the WakeVAS technologies.

  1. X-Ray structural investigation of VAS-393 crystals

    CERN Document Server

    Martirosian, A H; Harurtjunian, V S

    2001-01-01

    X-ray structural study of VAS-393 crystals was performed. Investigations were carried out with the use of the Weissenberg rotating and powder (employing the Bjornstrem diagrams) methods. The lattice constants ''c'' and ''a''are calculated. The crystal is shown to belong to the trigonal syngony (medium category)

  2. Congenital absence of vas deferens and ectopic kidney

    Directory of Open Access Journals (Sweden)

    Alobaidi Salwan

    2017-01-01

    Conclusion: Congenital absence of the vas deference is a unique clinical entity due to its great association with a large variety of urogenital abnormalities, we present this case to stress the importance of including scrotal examination in the routine physical exam to reduce the late diagnosis of such abnormality and it associated comorbidities.

  3. Nonlinear vibroacoustic wave modulations for structural damage detection: an overview

    Science.gov (United States)

    Pieczonka, Lukasz; Klepka, Andrzej; Martowicz, Adam; Staszewski, Wieslaw J.

    2016-01-01

    We present an overview of research developments related to the nonlinear vibroacoustic modulation technique used for structural damage detection. The method of interest is based on nonlinear interactions of a low-frequency pumping wave and a high-frequency probing wave. These two waves are introduced to monitored structures simultaneously. Then the presence of damage is exhibited by additional frequency components that result from nonlinear damage-wave interactions. A vast amount of research has been performed in this area over the last two decades. We aim to present the state-of-the-art of these developments. The major focus is on monitoring approaches, modeling aspects, actuation/sensing, signal processing, and application examples.

  4. Human response to vibroacoustic environments of space vehicles

    Science.gov (United States)

    Willshire, K. F.

    1984-01-01

    To insure efficient utilization of the system, space station design and operations will require special habitability considerations for the occupants and crew because of the relatively long duration missions. Of particular concern is the environment in which the personnel will live and work, and how it affects both the performance and comfort of the occupants. Current criteria do not consider possible effects of reduced gravity, long duration, and confinement. Preliminary to developing space station vibroacoustic habitability criteria, the adequacy of criteria for other space vehicles has been reviewed. In this paper, responses to the noise and vibration environments of both Skylab and Shuttle are discussed. Some astronauts have reported sleep interference, communication interference, distraction, and general annoyance as noise related complaints. In addition, information from the Russian Salyut missions, as well as similar based situtations (e.g., submarines), is reviewed.

  5. A vibroacoustic model of selected human larynx diseases.

    Science.gov (United States)

    Engel, Zbigniew Witold; Kłaczyński, Maciej; Wszołek, Wiesław

    2007-01-01

    With the present development of digital registration and methods for processing speech it is possible to make effective objective acoustic diagnostics for medical purposes. These methods are useful as all pathologies and diseases of the human vocal tract influence the quality of a patient's speech signal. Diagnostics of the voice organ can be defined as an unambiguous recognition of the current condition of a specific voice source. Such recognition is based on an evaluation of essential acoustic parameters of the speech signal. This requires creating a vibroacoustic model of selected deformations of Polish speech in relation to specific human larynx diseases. An analysis of speech and parameter mapping in 29-dimensional space is reviewed in this study. Speech parameters were extracted in time, frequency and cepstral (quefrency) domains resulting in diagrams that qualified symptoms and conditions of selected human larynx diseases. The paper presents graphically selected human larynx diseases.

  6. Automatic cough episode detection using a vibroacoustic sensor.

    Science.gov (United States)

    Mlynczak, Marcel; Pariaszewska, Katarzyna; Cybulski, Gerard

    2015-08-01

    Cough monitoring is an important element of the diagnostics of respiratory diseases. The European Respiratory Society recommends objective assessment of cough episodes and the search for methods of automatic analysis to make obtaining the quantitative parameters possible. The cough "events" could be classified by a microphone and a sensor that measures the vibrations of the chest. Analysis of the recorded signals consists of calculating the features vectors for selected episodes and of performing automatic classification using them. The aim of the study was to assess the accuracy of classification based on an artificial neural networks using vibroacoustic signals collected from chest. Six healthy, young men and eight healthy, young women carried out an imitated cough, hand clapping, speech and shouting. Three methods of parametrization were used to prepare the vectors of episode features - time domain, time-frequency domain and spectral modeling. We obtained the accuracy of 95% using artificial neural networks.

  7. Effect of Stagger on the Vibroacoustic Loads from Clustered Rockets

    Science.gov (United States)

    Rojo, Raymundo; Tinney, Charles E.; Ruf, Joseph H.

    2016-01-01

    The effect of stagger startup on the vibro-acoustic loads that form during the end- effects-regime of clustered rockets is studied using both full-scale (hot-gas) and laboratory scale (cold gas) data. Both configurations comprise three nozzles with thrust optimized parabolic contours that undergo free shock separated flow and restricted shock separated flow as well as an end-effects regime prior to flowing full. Acoustic pressure waveforms recorded at the base of the nozzle clusters are analyzed using various statistical metrics as well as time-frequency analysis. The findings reveal a significant reduction in end- effects-regime loads when engine ignition is staggered. However, regardless of stagger, both the skewness and kurtosis of the acoustic pressure time derivative elevate to the same levels during the end-effects-regime event thereby demonstrating the intermittence and impulsiveness of the acoustic waveforms that form during engine startup.

  8. Vibro-acoustic performance of newly designed tram track structures

    Science.gov (United States)

    Haladin, Ivo; Lakušić, Stjepan; Ahac, Maja

    2017-09-01

    Rail vehicles in interaction with a railway structure induce vibrations that are propagating to surrounding structures and cause noise disturbance in the surrounding areas. Since tram tracks in urban areas often share the running surface with road vehicles one of top priorities is to achieve low maintenance and long lasting structure. Research conducted in scope of this paper gives an overview of newly designed tram track structures designated for use on Zagreb tram network and their performance in terms of noise and vibration mitigation. Research has been conducted on a 150 m long test section consisted of three tram track types: standard tram track structure commonly used on tram lines in Zagreb, optimized tram structure for better noise and vibration mitigation and a slab track with double sleepers embedded in a concrete slab, which presents an entirely new approach of tram track construction in Zagreb. Track has been instrumented with acceleration sensors, strain gauges and revision shafts for inspection. Relative deformations give an insight into track structure dynamic load distribution through the exploitation period. Further the paper describes vibro-acoustic measurements conducted at the test site. To evaluate the track performance from the vibro-acoustical standpoint, detailed analysis of track decay rate has been analysed. Opposed to measurement technique using impact hammer for track decay rate measurements, newly developed measuring technique using vehicle pass by vibrations as a source of excitation has been proposed and analysed. Paper gives overview of the method, it’s benefits compared to standard method of track decay rate measurements and method evaluation based on noise measurements of the vehicle pass by.

  9. Ureteral Obstruction by the Vas Deferens after Urostomy

    OpenAIRE

    Vaidyanathan, Subramanian; Hughes, Peter L.; Soni, Bakul M.; Singh, Gurpreet

    2010-01-01

    A male patient with spina bifida and paraplegia, born in 1968, underwent urostomy in 1973. In 1999, he developed urine infections. Intravenous urography showed bilateral hydronephrosis and hydroureter. This patient continued to get recurrent urine infections. In 2009, computed tomography of the abdomen revealed dilatation of the ureters, but the ureters reverted to normal calibre as they passed forward through the anterior abdominal wall. The vas deferens on either side was crossing and kinki...

  10. Excitatory effect of a new polypeptide (anthopleurin-B) from sea anemone on the guinea-pig vas deferens.

    Science.gov (United States)

    Norton, T. R.; Ohizumi, Y.; Shibata, S.

    1981-01-01

    1 Anthopleurin-B (AP-B, greater than 3 x 10(-9) M), a newly isolated polypeptide from sea anemone (Anthopleura xanthogrammica), caused powerful rhythmic contractions in the guinea-pig isolated vas deferens. The other polypeptides anthopleurin-A from A. xanthogrammica and anthopleurin-C from A. elegantissima, elicited similar effects but in higher concentrations ( less than 5 x 10(-8) M). Toxin II (10(-6) M) isolated from the sea anemone, Anemonia sulcata, had no effect. 2 The rhythmic contractions induced by AP-B were inhibited by phentolamine, bretylium, guanethidine, reserpine, 6-hydroxydopamine, tetrodotoxin (TTX) and verapamil. Mecamylamine, atropine, methysergide, chlorpheniramine, and indomethacin had no effect. 3 AP-B (10(-8) M approximately 10(-5) M) caused a dose-dependent increase in the amount of endogenous noradrenaline (NA) released from the vas deferens. AP-B (10-5M) increased the amount of NA released to approximately 310 times (12 micrograms/g tissue) that of untreated tissues. 4 The AP-B-induced release of NA was inhibited or abolished by TTX, verapamil, or incubation in Ca-free medium. 5 These results suggest that the AP-B-induced rhythmic contraction of the vas deferens is mediated through the release of NA from adrenergic nerve endings; AP-B is one of the most potent substances in stimulating NA release from the vas deferens. PMID:7272600

  11. Principles of vibroacoustic testing of technological equipment of nuclear power plant primary coolant circuit

    Energy Technology Data Exchange (ETDEWEB)

    Samarin, A.A.; Adamenkov, K.A.; Krasyuk, V.Y.; Nozdrin, G.N.; Ivanov, Y.S.; Pospelko, K.A.

    1982-04-01

    Main principles are discussed of noise analysis as is its inclusion in the system of inspecting technological equipment of nuclear power plant primary circuits. Vibrations and noise resulting as system response to external perturbations are used as diagnostic signals. The mathematical formulation of the problem is done, the sources of vibrations and noise are determined, and the possibilities are discussed of analyzing the vibroacoustic signal and the changes in frequency characteristics to diagnose equipment failure states. Experiences are outlined with the placement of transducers in the Novovoronezh Nuclear Power Plant, which considerably affects the quality of control. A flow chart is shown for the vibroacoustic testing organization, and main trends are indicated of the study of vibroacoustic testing systems in nuclear power plants.

  12. Vibroacoustic optimization of anti-tetrachiral and auxetic hexagonal sandwich panels with gradient geometry

    Science.gov (United States)

    Ranjbar, Mostafa; Boldrin, Luca; Scarpa, Fabrizio; Neild, Simon; Patsias, Sophoclis

    2016-05-01

    The work describes the vibroacoustic behavior of anti-tetrachiral and auxetic hexagonal gradient sandwich panels using homogenized finite element models to determine the mechanical properties of the auxetic structures, the natural frequencies and radiated sound power level of sandwich panels made by the auxetic cores. The mechanical properties and the vibroacoustic behavior of auxetic hexagonal sandwich panels are investigated as a benchmark. The radiated sound power level of the structure over the frequency range of 0-1000 Hz is minimized by modifying the core geometry of the gradient auxetic sandwich panels. Several excitation cases are considered. First-order and random optimization methods are used for the minimization of radiated sound power level of the structures. The results of this study present significant insights into the design of auxetic structures with respect to their vibroacoustical properties.

  13. Luminal fluid of epididymis and vas deferens contributes to sperm chromatin fragmentation.

    Science.gov (United States)

    Gawecka, Joanna E; Boaz, Segal; Kasperson, Kay; Nguyen, Hieu; Evenson, Donald P; Ward, W Steven

    2015-12-01

    Do the luminal fluids of the epididymis and the vas deferens contribute to sperm chromatin fragmentation (SCF) in mice? The luminal fluids of both organs are required for activating SCF in mice, but the vas deferens luminal fluid does this more efficiently than that of the epididymis. Mice sperm have the ability to degrade their DNA in an apoptotic-like fashion when treated with divalent cations in a process termed SCF. SCF has two steps: the induction of reversible double-strand DNA breaks at the nuclear matrix attachment sites, followed by the irreversible degradation of DNA by nuclease. Single stranded DNA breaks accompany SCF. Luminal fluids from two reproductive organs of the mouse (B6D2F1 strain), the epididymis and vas deferens, were extracted and tested for SCF activation with divalent cations using four different combinations of the sperm and the surrounding luminal fluids: (i) in situ--sperm were kept in their luminal fluid and activated directly; (ii) reconstituted--sperm were centrifuged and resuspended in their luminal fluid before SCF activation; (iii) mixed--sperm were centrifuged and resuspended in the luminal fluid of the other organ; (iv) no luminal fluid--sperm were centrifuged and reconstituted in buffer. All four experiments were performed without (controls) and with divalent cations (resulting in SCF). For each experimental condition, two different mice were used and the analyses averaged. DNA damage by SCF was analyzed by three different methods, the sperm chromatin structure assay (SCSA), terminal deoxynucleotidyltransferase-mediated dUTP nick-end labeling (TUNEL) analysis and field inversion gel electrophoresis. In all three assays that we used, the vas deferens luminal fluid was much more efficient in stimulating SCF in the sperm from either source than that of the epididymis (P sperm were capable of initiating lower levels of SCF in the absence of luminal fluid (P sperm during their transit providing a mechanism to degrade the DNA. We

  14. Vibroacoustic payload environment prediction system (VAPEPS): Data base management center remote access guide

    Science.gov (United States)

    Thomas, V. C.

    1986-01-01

    A Vibroacoustic Data Base Management Center has been established at the Jet Propulsion Laboratory (JPL). The center utilizes the Vibroacoustic Payload Environment Prediction System (VAPEPS) software package to manage a data base of shuttle and expendable launch vehicle flight and ground test data. Remote terminal access over telephone lines to a dedicated VAPEPS computer system has been established to provide the payload community a convenient means of querying the global VAPEPS data base. This guide describes the functions of the JPL Data Base Management Center and contains instructions for utilizing the resources of the center.

  15. Improvement of vibroacoustic properties of toothed gears through constructional modifications of gear teeth

    Directory of Open Access Journals (Sweden)

    Andrzej WIECZOREK

    2009-01-01

    Full Text Available The paper draws attention to methods of minimizing values of vibroacoustic factors by reducing the sources. In the case of toothed gears such causes include, first of all, deviations in workmanship, excitations generated when teeth move in and out of mesh, as well as mesh stiffness variations. The paper presents results of experimental research on vibroacoustic properties of gear wheels with modified and non-modified high-profile teeth. Basing on these results, it was determined that the best results in counteracting vibrations and noise are obtained by using jointly an increased gear contact ratio and a tooth profile modification.

  16. Using the Saturn V and Titan III Vibroacoustic Databanks for Random Vibration Criteria Development

    Science.gov (United States)

    Ferbee, R C.

    2009-01-01

    This is an update to TN D-7159, "Development and Application of Vibroacoustic Structural Data Banks in Predicting Vibration Design and Test Criteria for Rocket Vehicle Structures", which was originally published in 1973. Errors in the original document have been corrected and additional data from the Titan III program have been included. Methods for using the vibroacoustic databanks for vibration test criteria development are shown, as well as all of the data with drawings and pictures of the measurement locations. An Excel spreadsheet with the data included is available from the author.

  17. Development of a vibroacoustic data base management and prediction system for payloads

    Science.gov (United States)

    On, F. J.; Hendricks, W.

    1982-01-01

    A data base management and prediction system called vibroacoustic payload environment prediction system (VAPEPS) was developed to serve as a repository for shuttle or extendable booster payload component flight and ground test data. This system is to be made available to the aerospace community for multiple uses including that of establishing the vibroacoustic environment for new payload components. The VAPEPS data includes that spectral information normally processed from vibration and acoustic measurements (e.g., power spectra, sound pressure level spectra, etc.). Results of development to provide this capability by NASA Goddard Space Flight Center and Lockheed Missiles and Space Company are described.

  18. VIBROACOUSTIC DIAGNOSING OF DISTURBANCES IN THE CAR IGNITION SYSTEM BY AMPLITUDE ESTIMATES

    Directory of Open Access Journals (Sweden)

    Piotr CZECH

    2014-06-01

    Full Text Available An important issue in vibroacoustic examination of engines is a correct interpretation of complex measured signals by applying property methods of their processing. The main tasks in diagnostics include: separation of a useful vibroacoustic signal and selection of characteristic, damage-sensitive features of the processed signal. The paper presents an attempt of detecting disturbances in the ignition system by measuring vibrations and noise. The object of the tests was a four-cylinder engine of a Volkswagen Polo car with swept capacity 1,0 dm3, adjusted to alternative power supply with the use of LPG gas fuel

  19. AVE/VAS 1: 25 mb sounding data

    Science.gov (United States)

    Sienkiewicz, M. E.

    1983-01-01

    The rawinsonde sounding program for the AVE/VAS I (shakedown) experiment is described. Tabulated data at 25-mb intervals for the 13 special rawinsonde stations and 1 National Weather Service station participating in the experiment are presented. Soundings were taken at 1200 and 1800 GMT on February 6, 1982, and at 0000 GMT on February 7, 1982. The method of processing soundings is discussed briefly, estimates of the RMS errors in the data are presented, and an example of contact data is given. Termination pressures of soundings are tabulated, as are observations of ground temperature at a depth of 2 cm.

  20. The AVE/VAS 2: The 25 mb sounding data

    Science.gov (United States)

    Sienkiewicz, M. E.

    1982-01-01

    The rawinsonde sounding program for the AVE/VAS II experiment is described and tabulated data at 25 mb intervals are presented. Soundings were taken at 3 hr intervals, was an 18 hour period. An additional sounding was taken at the normal synoptic observation time. The processing soundings method is discussed, estimates of the RMS errors in the data are presented, and an example of contact data is given. Termination pressures of soundings taken in the meso-beta-scale network are tabulated, as are observations of ground temperature at a depth of 2 cm.

  1. Predicting the vibroacoustic response of satellite equipment panels.

    Science.gov (United States)

    Conlon, S C; Hambric, S A

    2003-03-01

    Modern satellites are constructed of large, lightweight equipment panels that are strongly excited by acoustic pressures during launch. During design, performing vibroacoustic analyses to evaluate and ensure the integrity of the complex electronics mounted on the panels is critical. In this study the attached equipment is explicitly addressed and how its properties affect the panel responses is characterized. FEA and BEA methods are used to derive realistic parameters to input to a SEA hybrid model of a panel with multiple attachments. Specifically, conductance/modal density and radiation efficiency for nonhomogeneous panel structures with and without mass loading are computed. The validity of using the spatially averaged conductance of panels with irregular features for deriving the structure modal density is demonstrated. Maidanik's proposed method of modifying the traditional SEA input power is implemented, illustrating the importance of accounting for system internal couplings when calculating the external input power. The predictions using the SEA hybrid model agree with the measured data trends, and are found to be most sensitive to the assumed dynamic mass ratio (attachments/structure) and the attachment internal loss factor. Additional experimental and analytical investigations are recommended to better characterize dynamic masses, modal densities and loss factors.

  2. Voice acoustic patterns of patients diagnosed with vibroacoustic disease.

    Science.gov (United States)

    Mendes, Ana; Alves-Pereira, Mariana; Castelo Branco, Nuno A A

    2006-01-01

    Long-term low frequency noise exposure (LFN) (vibroacoustic disease (VAD), a systemic pathology characterized by the abnormal growth of extra-cellular matrices. The respiratory system is a target for LFN. Fibrosis of the respiratory tract epithelia was observed in VAD patients through biopsy, and confirmed in animal models exposed to LFN. Voice acoustic analysis can detect vocal fold variations of mass, tension, muscular and neural activity. Frequency perturbation (jitter), amplitude perturbation (shimmer) and harmonic-to-noise ratio (HNR) are used in the evaluation of the vocal function, and can be indicators of the presence and degree of severity of vocal pathology. Since the respiratory system is the energy source of the phonation process, this raises questions about the effects of VAD on voice production. The purpose of this study was to determine if voice acoustic parameters of VAD patients are different from normative data. Nine individuals (5 males and 4 females) diagnosed with VAD were recorded performing spoken and sung tasks. The spoken tasks included sustaining vowels and fricatives. The sung tasks consisted of maximum phonational frequency range (MPFR). Voice acoustic parameters ana- lysed were: fundamental frequency (F0), jitter, shimmer, HNR and temporal measures. Compared with normative data, both males and females diagnosed with VAD exhibited increased F0, shimmer and HNR. Jitter, MPFR and one temporal measure were reduced. VAD individuals presented voice acoustic parameter differences in spectral, temporal and perturbation measures, which may be indicative of small morphological changes in the phonatory system.

  3. Vibroacoustic Response Data of Stiffened Panels and Cylinders

    Science.gov (United States)

    Cabell, Randolph; Klos, Jake; Buehrle, Ralph; Schiller, Noah

    2008-01-01

    NASA has collected vibroacoustic response data on a variety of complex, aerospace structures to support research into numerical modeling of such structures. This data is being made available to the modeling community to promote the development and validation of analysis methods for these types of structures. Existing data from two structures is described, as well as plans for a data set from a third structure. The first structure is a 1.22 m by 1.22 m stiffened aluminum panel, typical of a commercial aircraft sidewall section. The second is an enclosed, stiffened aluminum cylinder, approximately 3.66 m long and 1.22 m in diameter, constructed to resemble a small aircraft fuselage with no windows and a periodic structure. The third structure is a filament-wound composite cylinder with composite stiffeners. Numerous combinations of excitation and response variables were measured on the structures, including: shaker excitation; diffuse acoustic field; velocity response from a laser vibrometer; intensity scans; and point acceleration.

  4. Fetal brain activity and hemodynamic response to a vibroacoustic stimulus.

    Science.gov (United States)

    Fulford, Jonathan; Vadeyar, Shantala H; Dodampahala, Sanani H; Ong, Stephen; Moore, Rachel J; Baker, Philip N; James, David K; Gowland, Penny

    2004-06-01

    Previous studies have demonstrated the practicality of using functional magnetic resonance imaging (fMRI) techniques to assess fetal brain activity. The purpose of this study was to compare the fetal hemodynamic response to that of the adult. Seventeen pregnant subjects, all of whom were at more than 36 weeks gestation were scanned while the fetus was exposed to a vibroacoustic stimulus. Thirteen adult subjects were scanned with an equivalent acoustic stimulus. Of the fetal subjects, two could not be analyzed due to technical problems, eight did not show significant activation, and seven showed significant activation. In all cases, activation was localized within the temporal region. Measures of fetal hemodynamic responses revealed an average time to peak (ttp) of 7.36 +/- 0.94 sec and an average percentage change of 2.67 +/- 0.93%. In contrast, activation was detected in 5 of 13 adults with an average ttp of 6.54 +/- 0.54 sec and an average percentage change of 1.02 +/- 0.40%. The measurement of changes in the fetal hemodynamic response may be important in assessing compromised pregnancies. Copyright 2004 Wiley-Liss, Inc.

  5. Epilepsy in the vibroacoustic disease: a case report.

    Science.gov (United States)

    Martinho Pimenta, A J; Castelo Branco, N A

    1999-03-01

    Late-onset epilepsy was one of the first neurological problems identified in patients diagnosed with vibroacoustic disease. Other clinical situations, such as automatisms and rage-like reaction crises were also observed. Some cases of epileptic seizures were triggered by different types of stimuli. This study describes the clinical case of a 30-yr-old male metal-worker who had epileptic seizures when he used vibratory tools common to his profession, such as drills and sanders. We performed a 21-channel EEG during a seizure induced in the laboratory by direct contact of a vibratory tool with his right hand. This allowed us to view the electrical discharge of his left hemisphere. The entire procedure was simultaneously videotaped while a partial motor crisis was observed. Brain MRI of this subject revealed multiple hyperintense focal lesions in the sub-cortical white matter. Echocardiography revealed thickening of the pericardium and valve structures. To the authors' knowledge, this is the first documented case of reflex epilepsy due to vibratory stimuli. We briefly discuss the possible pathophysiological mechanisms of this clinical event.

  6. Involvement of central airways in vibroacoustic disease patients.

    Science.gov (United States)

    Ferreira, José Reis; Monteiro, Miguel B; Tavares, Fernanda; Serrano, Isabel; Monteiro, Emanuel; Mendes, Carla P; Alves-Pereira, Mariana; Branco, Nuno A A Castelo

    2006-01-01

    Vibroacoustic disease (VAD) is the whole-body pathology caused by excessive exposure to LFN. For the past 25 years, it has been know that low frequency noise (LFN, < 500 Hz, including infrasound) targets the respiratory system. In LFN-exposed rodents, the morphological changes of respiratory tract tissue partially explained some respiratory symptoms reported by VAD patients. However, many questions remain unanswered. Recently, some volunteer VAD patients underwent bronchoscopy in order to ascertain possible damage that could be associated with their respiratory complaints. Fourteen fully-informed and volunteer VAD patients were submitted to bronchoscopy, and biopsies were removed for analysis. All patients exhibited small submucosal vascular-like lesions near the spurs, consisting of increased collagen and elastin fibres. Histology disclosed cilliary abnormalities, basal membrane hyperplasia, and thickening of vessel walls. In five patients, collagen bundles appeared degenerative and disrupted. No inflammatory process was ever identified, and no differences were seen between smokers and non-smokers. Data is in accordance with what was observed in LFN-exposed animal models and also in 8 VAD patients who developed lung tumours. Collagen disruption and degeneration was also observed in electron microscopy images of the respiratory tract of LFN-exposed rodents. Thickened blood and lymphatic vessel walls have been consistently seen in images of VAD patients and of LFN-exposed rodents. During bronchoscopy performed by other reasons, this sort of structural aspects is not frequently seen. Taken together, it is strongly suggested that these findings could be VAD-specific.

  7. Interpositional substitution of free vas deferens segment autografts in rat: feasibility and potential implications

    OpenAIRE

    Kadioglu, Teoman Cem; Temple-Smith, Peter D; Southwick, Graeme

    2014-01-01

    Background Insufficient vas length for performing a tension-free vasovasostomy is a problem occasionally encountered by microsurgeons. Herein we evaluated utilization of a non-vascularized vas deferens autograft in a rat model. Methods Segments of isolated vas deferens, 2.5 cm in length, were used as bilateral autografts in 15 rats. Each autograft was implanted between the two transected ends of vas deferens using end-to-end anastomosis. Fertility, sperm motility, and graft survival was evalu...

  8. [Vibroacoustic factors hygienic regulation principles in Russia and abroad evolution and succession].

    Science.gov (United States)

    Prokopenko, L V; Kravchenko, O K; Ermolenko, A E; Kurierov, N N; Lagutina, A V; Tseitlina, G S

    2013-01-01

    Brief historical summary about Institute' vibroacoustic factors investigations development in the XXth century is presented. There are shown the data of noise, vibration, ultra- and infrasound hygienic rating in comparison with international approaches; the ways of its international harmonization in modern social and economic situation are selected.

  9. Utilization of old vibro-acoustic measuring equipment to grasp basic concepts of vibration measurements

    DEFF Research Database (Denmark)

    Darula, Radoslav

    2013-01-01

    The aim of the paper is to show that even old vibro-acoustic (analog) equipment can be used as a very suitable teaching equipment to grasp basic principles of measurements in an era, when measurement equipments are more-or-less treated as ‘black-boxes’, i.e. the user cannot see directly how...

  10. Joint motion quality in vibroacoustic signal analysis for patients with patellofemoral joint disorders.

    Science.gov (United States)

    Bączkowicz, Dawid; Majorczyk, Edyta

    2014-12-12

    Chondromalacia, lateral patellar compression syndrome and osteoarthritis are common patellofemoral joint disorders leading to functional and/or structural disturbances in articular surfaces. The objective of the study was to evaluate their impact on joint motion quality via the vibroacoustic signal generated during joint movement analysis. Seventy-three patients (30 with chondromalacia, 21 with lateral patellar compression syndrome, and 22 with osteoarthritis) and 32 healthy controls were tested during flexion/extension knee motion for vibroacoustic signals using an acceleration sensor. Estimated parameters: variation of mean square (VMS), difference between mean of four maximum and mean of four minimum values (R4), power spectral density for frequency of 50-250 Hz (P1) and 250-450 Hz (P2) were analyzed. Vibroacoustic signals recorded for particular disorders were characterized by significantly higher values of parameters in comparison to the control group. Moreover, differences were found among the various types of patellofemoral joint disturbances. Chondromalacia and osteoarthritis groups showed differences in all parameters examined. In addition, osteoarthritis patients exhibited differences in VMS, P1 and P2 values in comparison to lateral patellar compression syndrome patients. However, only the value of R4 was found to differ between knees with lateral patellar compression syndrome and those with chondromalacia. Our results suggest that particular disorders are characterized by specific vibroacoustic patterns of waveforms as well as values of analyzed parameters.

  11. Vibroacoustic Response of Residential Housing due to Sonic Boom Exposure: A Summary of two Field Tests

    Science.gov (United States)

    Klos, Jacob; Buehrle, Ralph; Sullivan, Brenda; Gavin, Joseph; Salamone, Joseph; Haering, Edward A., jr.; Miller, Denise M.

    2008-01-01

    Two experiments have been performed to measure the vibroacoustic response of houses exposed to sonic booms. In 2006, an old home in the base housing area of Edwards Air Force Base, built around 1960 and demolished in 2007, was instrumented with 288 transducers. During a 2007 follow-on test, a newer home in the base housing area, built in 1997, was instrumented with 112 transducers. For each experiment, accelerometers were placed on walls, windows and ceilings in bedrooms of the house to measure the vibration response of the structure. Microphones were placed outside and inside the house to measure the excitation field and resulting interior sound field. The vibroacoustic response of each house was measured for sonic boom amplitudes spanning from 2.4 to 96 Pa (0.05 to 2 lbf/sq ft). The boom amplitudes were systematically varied using a unique dive maneuver of an F/A-18 airplane. In total, the database for both houses contains vibroacoustic response data for 154 sonic booms. In addition, several tests were performed with mechanical shaker excitation of the structure to characterize the forced response of the houses. The purpose of this paper is to summarize all the data from these experiments that are available to the research community, and to compare and contrast the vibroacoustic behavior of these two dissimilar houses.

  12. Vibro-Acoustic modulation based damage identification in a composite skin-stiffener structure

    NARCIS (Netherlands)

    Ooijevaar, T.H.; Loendersloot, Richard; Rogge, M.D.; Akkerman, Remko; Tinga, Tiedo; Le Cam, V.; Mevel, L.; Schoefs, F.

    2014-01-01

    The vibro-acoustic modulation method is applied to a composite skin-stiffener structure to investigate the possibilities to utilise this method for damage identification in terms of detection, localisation and damage quantification. The research comprises a theoretical part and an experimental part.

  13. Vibro-Acoustic Numerical Analysis for the Chain Cover of a Car Engine

    National Research Council Canada - National Science Library

    Enrico Armentani; Raffaele Sepe; Antonio Parente; Mauro Pirelli

    2017-01-01

    In this work, a vibro-acoustic numerical and experimental analysis was carried out for the chain cover of a low powered four-cylinder four-stroke diesel engine, belonging to the FPT (FCA Power Train) family called SDE (Small Diesel Engine...

  14. AVE/VAS 3: 25-mb sounding data

    Science.gov (United States)

    Sienkiewicz, M. E.

    1982-01-01

    The rawinsonde sounding program for the AVE/VAS 3 experiment is described. Tabulated data are presented at 25-mb intervals for the 24 National Weather Service stations and 14 special stations participating in the experiment. Soundings were taken at 3-hr intervals, beginning at 1200 GMT on March 27, 1982, and ending at 0600 GMT on March 28, 1982 (7 sounding times). An additional sounding was taken at the National Weather Service stations at 1200 GMT on March 28, 1982, at the normal synoptic observation time. The method of processing soundings is briefly discussed, estimates of the RMS errors in the data are presented, and an example of contact data is given. Termination pressures of soundings taken in the mesos-beta-scale network are tabulated, as are observations of ground temperature at a depth of 2 cm.

  15. Characterization of capsaicin induced responses in mice vas deferens

    DEFF Research Database (Denmark)

    Sheykhzade, Majid; Gupta, Saurabh; Sørensen, Tinne

    2011-01-01

    -depth in isolated preparations. The present study sets out to study and characterize the capsaicin as well as CGRP-induced responses in isolated mouse vas deferens. The effects of capsaicin and CGRP family of peptides were studied on electrically-induced twitch responses in the absence or presence of transient...... receptor potential cation channel vanilloid subfamily member 1 (TRPV1) antagonist and CGRP receptor antagonists. Twitch responses were attenuated by capsaicin (1nM-30nM) and CGRP family of peptides. The potency order was CGRP>intermedin-long (IMDL)~[Cys(Et)(2,7)]aCGRP~adrenomedullin (AM)>[Cys(ACM)(2,7)]a......CGRP>amylin (AMY). These responses were disinhibited by the CGRP receptor antagonists and TRPV1 antagonists. The addition of CGRP receptor antagonists caused a transient potentiation of the twitch response and this potentiation was blocked by pretreatment with capsaicin and enhanced by incubation with exogenous...

  16. Respiratory pathology in vibroacoustic disease: 25 years of research.

    Science.gov (United States)

    Branco, Nuno A A Castelo; Ferreira, José Reis; Alves-Pereira, Mariana

    2007-01-01

    Respiratory pathology induced by low frequency noise (LFN, vibroacoustic disease (VAD), a whole-body pathology caused by excessive exposure to LFN, respiratory pathology takes on specific features. Initially, respiratory pathology was not considered a con- sequence of LFN exposure; but today, LFN can be regarded as a major agent of disease that targets the respiratory system. The goal of this report is to put forth what is known to date on the clinical signs of respiratory pathology seen in VAD patients. Data from the past 25 years of research will be taken together and presented. In persons exposed to LFN on the job, respiratory complaints appear af- ter the first 4 years of professional activity. At this stage, they disappear during vacation periods or when the person is removed form his /her workstation for other reasons. With long-term exposure, more serious situations can arise, such as, atypical pleural effusion, respiratory insufficiency, fibrosis and tumours. There is no correlation with smoking habits. In LFN-exposed animal models, morphological changes of the pleura, and loss of the phagocytic ability of pleural mesothelial cells (explaining the atypical pleural effusions). Fibrotic lesions and neo-vascularization were observed along the entire respiratory tract. Fibrosis lesions and neovascularisation were observed through- out the respiratory tract of the animals seen. Pre-malignant lesions, metaplasia e displasia, were also identified. LFN is an agent of disease and the respiratory tract is one of its preferential targets. The respiratory pathology associated with VAD needs further in-depth studies in order to achieve a greater understanding, and develop methods of pharmaco- logical intervention.

  17. How the factoid of wind turbines causing ‘vibroacoustic disease’ came to be ‘irrefutably demonstrated’

    National Research Council Canada - National Science Library

    Chapman, Simon; St George, Alexis

    2013-01-01

    ... of these, “vibroacoustic disease” (VAD) is frequently mentioned. The aim of this study is to examine the quality of the evidence on how VAD came to be associated with wind turbine exposure by wind farm opponents. Methods...

  18. Airway flow limitation in patients with vibroacoustic disease.

    Science.gov (United States)

    Reis Ferreira, J M; Couto, A R; Jalles-Tavares, N; Castelo Branco, M S; Castelo Branco, N A

    1999-03-01

    Vibroacoustic disease (VAD) is a pathology caused by occupational exposure to large pressure amplitude and low frequency (LPALF) noise (> or =90 dB SPL, < or =500 Hz), and has been the object of study by this group for the past 20 yr. In a group of 140 VAD-diagnosed patients, 7 non-smoker aircraft technicians developed clinical signs of respiratory insufficiency at an early age. Previously, multi-focal fibrosis had been observed in the lung of Wistar rats exposed to occupationally simulated LPALF noise and with no possibility of contamination by fumes, dust or other chemical agents. The goal of this study is to compare pulmonary imaging and/or functional changes in two age- and exposure-time matched groups of VAD-diagnosed aircraft technicians, with and without airflow limitation symptoms. In a population of 140 individuals occupationally exposed to LPALF noise and diagnosed with VAD, we excluded the smokers (45 cases) and selected 7 individuals with complaints of airway flow limitations, average age 42.3 yr (SD = 2.3). From the remaining non-smokers without respiratory complaints, we selected a group of 15, age-matched patients (average age 36 yr, SD = 6.5). All subjects received a high-resolution CT scan of the chest and respiratory function tests consisting of body plethysmography, spirometry and metacholine airway provocation. There is a significant relationship between the presence of symptoms and imaging of lung fibrosis through high-resolution CT scan (p = 0.03624). There are no significant differences when both groups are compared with respect to the percentage of predicted values of lung function: Vital Capacity (VC), Total Lung Capacity, Forced Expiratory Volume during the first second of expiration, Maximal Expiratory Flow at 50% VC, Total Airway Resistance, and Airway Reactivity after 25 mg of metacholine. High resolution CT scan is a valuable tool for diagnosis of lung fibrosis in VAD patients who have symptoms of airway flow limitations. The fact that

  19. Vibro-acoustic model of an active aircraft cabin window

    Science.gov (United States)

    Aloufi, Badr; Behdinan, Kamran; Zu, Jean

    2017-06-01

    This paper presents modeling and design of an active structural acoustic control (ASAC) system for controlling the low frequency sound field transmitted through an aircraft cabin window. The system uses stacked piezoelectric elements arranged in a manner to generate out-of-plane actuation point forces acting on the window panel boundaries. A theoretical vibro-acoustic model for an active quadruple-panel system is developed to characterize the dynamic behavior of the system and achieve a good understanding of the active control performance and the physical phenomena of the sound transmission loss (STL) characteristics. The quadruple-panel system represents the passenger window design used in some classes of modern aircraft with an exterior double pane of Plexiglas, an interior dust cover pane and a glazed dimmable pane, all separated by thin air cavities. The STL characteristics of identical pane window configurations with different piezoelectric actuator sets are analyzed. A parametric study describes the influence of important active parameters, such as the input voltage, number and location of the actuator elements, on the STL is investigated. In addition, a mathematical model for obtaining the optimal input voltage is developed to improve the acoustic attenuation capability of the control system. In general, the achieved results indicate that the proposed ASAC design offers a considerable improvement in the passive sound loss performance of cabin window design without significant effects, such as weight increase, on the original design. Also, the results show that the acoustic control of the active model with piezoelectric actuators bonded to the dust cover pane generates high structural vibrations in the radiating panel (dust cover) and an increase in sound power radiation. High active acoustic attenuation can be achieved by designing the ASAC system to apply active control forces on the inner Plexiglas panel or dimmable panel by installing the actuators on the

  20. Vas deferens and penis development in the imposex-exhibiting female rock shell, Thais clavigera.

    Science.gov (United States)

    Horiguchi, Toshihiro; Ohta, Yasuhiko; Urushitani, Hiroshi; Lee, Jeong-Hoon; Park, Jeong-Chae; Cho, Hyeon-Seo; Shiraishi, Hiroaki

    2012-05-01

    The characteristics of the development of male genitalia (penis and vas deferens) in imposex-exhibiting female rock shells, Thais clavigera, were histologically examined using specimens from a wild population and tributyltin (TBT)-exposed females in the laboratory. A variety of vas deferens morphogenesis patterns were observed in wild female T. clavigera, and the characteristics were summarized. The immature vas deferens at an initial stage, however, was only observed beneath or behind the penis, and no vas deferens was observed close to the vaginal opening (i.e., vulva) of the capsule gland in TBT-exposed females, which was different from the characteristics of vas deferens formation observed in wild females. Taking into consideration both the observed results from wild female specimens and from TBT-exposed females in the laboratory, the vas deferens sequence (VDS) index for T. clavigera was proposed as VDS 1-6. Copyright © 2011 Elsevier Ltd. All rights reserved.

  1. Involvement of central airways in vibroacoustic disease patients

    Directory of Open Access Journals (Sweden)

    José Reis Ferreira

    2006-03-01

    Full Text Available Introduction. Vibroacoustic disease (VAD is the whole-body pathology caused by excessive exposure to LFN. For the past 25 years, it has been know that low frequency noise (LFN, <500 Hz, including infrasound targets the respiratory system. In LFN-exposed rodents, the morphological changes of respiratory tract tissue partially explained some respiratory symptoms reported by VAD patients. However, many questions remain unanswered. Recently, some volunteer VAD patients underwent bronchoscopy in order to ascertain possible damage that could be associated with their respiratory complaints. Methods. Fourteen fully-informed and volunteer VAD patients were submitted to bronchoscopy, and biopsies were removed for analysis. Results. All patients exhibited small submucosal vascular-like lesions near the spurs, consisting of increased collagen and elastin fibres. Histology disclosed cilliary abnormalities, basal membrane hyperplasia, and thickening of vessel walls. In five patients, collagen bundles appeared degenerative and disrupted. No inflammatory process was ever identified, and no differences were seen between smokers and non-smokers. Discussion. Data is in accordance with what was observed in LFN-exposed animal models and also in 8 VAD patients who developed lung tumours. Collagen disruption and degeneration was also observed in electron microscopy images of the respiratory tract of LFN-exposed rodents. Thickened blood and lymphatic vessel walls have been consistently seen in images of VAD patients and of LFN-exposed rodents. During bronchoscopy performed by other reasons, this sort of structural aspects is not frequently seen. Taken together, it is strongly suggested that these findings could be VAD-specific. Resumo: Nos últimos vinte cinco anos constatou-se que o aparelho respiratório constitui um alvo do ruído de baixa frequência (RFB <500Hz, incluindo infra-sons. Denomina-se doença vibroacústica (VAD a patologia sistémica causada pela

  2. Respiratory pathology in vibroacoustic disease: 25 years of research

    Directory of Open Access Journals (Sweden)

    Nuno A.A. Castelo Branco

    2007-01-01

    Full Text Available Background: Respiratory pathology induced by low frequency noise (LFN, <500 Hz, including infrasound is not a novel subject given that in the 1960's, within the context of U.S. and U.S.S.R. Space Programs, other authors have already reported its existence. Within the scope of vibroacoustic disease (VAD, a whole-body pathology caused by excessive exposure to LFN, respiratory pathology takes on specific features. Initially, respiratory pathology was not considered a consequence of LFN exposure; but today, LFN can be regarded as a major agent of disease that targets the respiratory system. The goal of this report is to put forth what is known to date on the clinical signs of respiratory pathology seen in VAD patients. Methods: Data from the past 25 years of research will be taken together and presented. Results: In persons exposed to LFN on the job, respiratory complaints appear after the first 4 years of professional activity. At this stage, they disappear during vacation periods or when the person is removed form his /her workstation for other reasons. With long-term exposure, more serious situations can arise, such as, atypical pleural effusion, respiratory insufficiency, fibrosis and tumours. There is no correlation with smoking habits. In LFN--exposed animal models, morphological changes of the pleura, and loss of the phagocytic ability of pleural mesothelial cells (explaining the atypical pleural effusions. Fibrotic lesions and neo-vascularization were observed along the entire respiratory tract. Fibrosis lesions and neovascularisation were observed throughout the respiratory tract of the animals seen. Pre-malignant lesions, metaplasia e displasia, were also identified. Discussion: LFN is an agent of disease and the respiratory tract is one of its preferential targets. The respiratory pathology associated with VAD needs further in-depth studies in order to achieve a greater understanding, and develop methods of pharmacological intervention

  3. JAXA Activities on Prediction of Vibroacoustic Prediction for Panel Mounted Equipments

    Science.gov (United States)

    Akagi, Hiroki; Ando, Shigemasa; Yanagase, Keiichi; Shi, Qinzhong

    2012-07-01

    Spacecraft is exposed to the severe random vibration by acoustic during its launch. In the spacecraft design, random vibration of spacecraft equipments mounted on panel structure during launch environments needs to be predicted. In the present methods, SEA is the method for analyzing the high frequency band, FEA is for the low frequency band. This paper introduces major methods of recent years to predict the vibroacoustic response of spacecraft structure, including SEA, Joint Acceptance and most recent approach using Combination of FEA and SEA methods. The Combination method focuses on the vibroacoustic prediction which keeps advantages to use detail model of structure expressed by FEA and statistical energy approach expressed by SEA of reverberant acoustic excitation. These methods are applied to diffuse sound field excitation of honeycomb panel, and compared with the results in test verification.

  4. Prediction of the Vibroacoustic Response of the Equipment Mounted on the Infrared Space Telescope "SPICA"

    Science.gov (United States)

    Akagi, Hiroki; Ando, Shigemasa; Shi, Qinzhong; Yamawaki, Toshiko

    2014-06-01

    The infrared space telescope "SPICA" (Space Infrared Telescope for Cosmology and Astrophysics) is a structurally-complex spacecraft, which requires the less conservative prediction of the random vibration at interface in order to reduce the over-margin issue for designing the strength on critical structure of optical instrument in the early stage of development, and to relieve the risk of overweight designing. This paper proposes Combination of FEA and SEA Methods to predict the vibroacoustic response of the equipment mounted on SPICA, and less conservative specification of the random vibration environments. Furthermore, a method of force-limiting to notch the specification over a certain frequency range during designing and a random vibration test is shown. Force-limiting specification is calculated using a simplified approach by multiplying the article's apparent mass to the equivalent of vibroacoustic response at interface.

  5. Analytical coupled vibroacoustic modeling of membrane-type acoustic metamaterials: Plate model

    Science.gov (United States)

    Chen, Yangyang; Huang, Guoliang; Zhou, Xiaoming; Hu, Gengkai; Sun, Chin-Teh

    2014-12-01

    By considering the membrane's dissipation, the membrane-type acoustic metamaterial (MAM) has been demonstrated as a super absorber for low-frequency sound. In the paper, a theoretical vibroacoustic plate model is developed to reveal sound energy absorption mechanism within the MAM under a plane normal incidence. Based on the plate model in conjunction with the point matching method, the in-plane strain energy of the membrane due to the resonant and antiresonant motion of the attached masses can be accurately captured by solving the coupled vibroacoustic integrodifferential equation. Therefore, the sound absorption of the MAM is obtained and discussed, which is also in good agreement with the prediction from the finite element method. In particular, microstructure effects including eccentricity of the attached masses, the depth, thickness and loss factor of the membrane on sound absorption peak values are quantitatively investigated.

  6. Vibroacoustic Characterization of Corrugated-Core and Honeycomb-Core Sandwich Panels

    Science.gov (United States)

    Allen, Albert; Schiller, Noah

    2016-01-01

    The vibroacoustic characteristics of two candidate launch vehicle fairing structures, corrugated- core and honeycomb-core sandwich designs, were studied. The study of these structures has been motivated by recent risk reduction efforts focused on mitigating high noise levels within the payload bays of large launch vehicles during launch. The corrugated-core sandwich concept is of particular interest as a dual purpose structure due to its ability to harbor resonant noise control systems without appreciably adding mass or taking up additional volume. Specifically, modal information, wavelength dispersion, and damping were determined from a series of vibrometer measurements and subsequent analysis procedures carried out on two test panels. Numerical and analytical modeling techniques were also used to assess assumed material properties and to further illuminate underlying structural dynamic aspects. Results from the tests and analyses described herein may serve as a reference for additional vibroacoustic studies involving these or similar structures.

  7. Vibro-acoustics of ribbed structures: A compact modal formulation for SEA models

    Science.gov (United States)

    Bremner, Paul G.

    Rib-stiffening of plates and shells is a structurally-efficient construction technique common to aerospace, shipbuilding, automotive, and many other industries. Engineers need to be able to design the vibro-acoustic behavior of these panel systems. That is, the panel vibration response to excitation by a sound pressure field and the sound radiated by panel vibration. The effect of adding rib-stiffeners to a uniform thickness, isotropic panel is to cause scattering of the panel free bending waves. The superposition of these wavefields can also be described by modal methods, if the panel has finite dimensions. The effect of rib stiffening is shown to be the re-distribution of resonant frequencies and mode shapes of the panel, which can significantly alter its noise and vibration character. This paper describes a compact modal method for description of the vibro-acoustics of ribbed panels which is currently implemented in the Statistical Energy Analysis modeling package AutoSEA.

  8. SOME PROBLEMS WITH VIBROACOUSTIC METHOD IN RELATION TO THE TRANSMISSION GEARBOX OF A MILITARY HELICOPTER

    Directory of Open Access Journals (Sweden)

    Paweł MAJEWSKI

    2016-12-01

    Full Text Available The article presents the results of a laboratory gear stage with regard to deepening its consumption. In addition, the study looked at the construction of the transmission gearbox of a military helicopter, according to the basic kinematic results of the analysis of vibroacoustic signals, in order to determine the diagnostic criteria for the assessment of the technical condition of a military helicopter’s transmission gearbox.

  9. Shuttle payload vibroacoustic test plan evaluation. Free flyer payload applications and sortie payload parametric variations

    Science.gov (United States)

    Stahle, C. V.; Gongloff, H. R.

    1977-01-01

    A preliminary assessment of vibroacoustic test plan optimization for free flyer STS payloads is presented and the effects on alternate test plans for Spacelab sortie payloads number of missions are also examined. The component vibration failure probability and the number of components in the housekeeping subassemblies are provided. Decision models are used to evaluate the cost effectiveness of seven alternate test plans using protoflight hardware.

  10. The problem of carrying out a diagnosis of an internal combustion engine by vibroacoustical parameters

    Science.gov (United States)

    Lukanin, V. N.; Sidorov, V. I.

    1973-01-01

    The physics of noise formation in an internal combustion engine is discussed. A dependence of the acoustical radiation on the engine operating process, its construction, and operational parameters, as well as on the degree of wear on its parts, has been established. An example of tests conducted on an internal combustion engine is provided. A system for cybernetic diagnostics for internal combustion engines by vibroacoustical parameters is diagrammed.

  11. Vibroacoustic Tailoring of a Rod-Stiffened Composite Fuselage Panel with Multidisciplinary Considerations

    Science.gov (United States)

    Allen, Albert R.; Przekop, Adam

    2015-01-01

    An efficient multi-objective design tailoring procedure seeking to improve the vibroacoustic performance of a fuselage panel while maintaining or reducing weight is presented. The structure considered is the pultruded rod stitched efficient unitized structure, a highly integrated composite structure concept designed for a noncylindrical, next-generation flight vehicle fuselage. Modifications to a baseline design are evaluated within a six-parameter design space including spacing, flange width, and web height for both frame and stringer substructure components. The change in sound power radiation attributed to a design change is predicted using finite-element models sized and meshed for analyses in the 500 Hz, 1 kHz, and 2 kHz octave bands. Three design studies are carried out in parallel while considering a diffuse acoustic field excitation and two types of turbulent boundary-layer excitation. Kriging surrogate models are used to reduce the computational costs of resolving the vibroacoustic and weight objective Pareto fronts. The resulting Pareto optimal designs are then evaluated under a static pressurization ultimate load to assess structural strength and stability. Results suggest that choosing alternative configurations within the considered design space can reduce weight and improve vibroacoustic performance without compromising strength and stability of the structure under the static load condition considered, but the tradeoffs are significantly influenced by the spatial characteristics of the assumed excitation field.

  12. Correlation of FEM/BEM Vibroacoustic Prediction to System-Level Acoustic Test Results

    Science.gov (United States)

    Rodrigues, G.; Ngan, I.; Santiago-Prowald, J.

    2014-06-01

    Coupled FEM/BEM vibroacoustic analyses are employed for deriving spacecraft random vibration environments and supporting the design of low aerial density structures. They offer deterministic predictions which are very accurate at low-frequency and meaningful across all the spectrum of interest for vibroacoustic response.An assessment of the standard procedure of FEM/BEM vibroacoustic analyses was carried out by correlation to measurements from system-level tests of several spacecraft. This allowed a quantification of the typical errors committed, and concluded on the adequacy of applying the standard factor of safety +4dB to the predictions. It was observed that a major source of error is the lack of representativeness of the models of the spacecraft, which adds to the diffuse field idealization made on the acoustic environment inside the fairing and the test chambers. In particular, it was observed a clear impact from a lack of detail of the damping of the structure, and an often crude lumped representation of units and equipment as well as tanks and fixations.

  13. Joint Motion Quality in Chondromalacia Progression Assessed by Vibroacoustic Signal Analysis.

    Science.gov (United States)

    Bączkowicz, Dawid; Majorczyk, Edyta

    2016-11-01

    Because of the specific biomechanical environment of the patellofemoral joint, chondral disorders, including chondromalacia, often are observed in this articulation. Chondromalacia via pathologic changes in cartilage may lead to qualitative impairment of knee joint motion. To determine the patellofemoral joint motion quality in particular chondromalacia stages and to compare with controls. Retrospective, comparative study. Voivodship hospitals, university biomechanical laboratory. A total of 89 knees with chondromalacia (25 with stage I; 30 with stage II and 34 with stage III) from 50 patients and 64 control healthy knees (from 32 individuals). Vibroacoustic signal pattern analysis of joint motion quality. For all knees vibroacoustic signals were recorded. Each obtained signal was described by variation of mean square, mean range (R4), and power spectral density for frequency of 50-250 Hz (P1) and 250-450 Hz (P2) parameters. Differences between healthy controls and all chondromalacic knees as well as chondromalacia patellae groups were observed as an increase of analyzed parameters (P vibroacoustic signals, and there seems to be a relationship between the level of signal amplitude as well as frequency and cartilage destruction from the superficial layer to the subchondral bone. IV. Copyright © 2016 American Academy of Physical Medicine and Rehabilitation. Published by Elsevier Inc. All rights reserved.

  14. Validation and Findings Comparing VAS vs. Likert Scales for Psychosocial Measurements

    Science.gov (United States)

    Hasson, Dan; Arnetz, Bengt B.

    2005-01-01

    Context: Psychosocial exposures commonly show large variation over time and are usually assessed using multi-item Likert indices. A construct requiring a five-item Likert index could possibly be replaced by a single visual analogue scale (VAS). Objective: To: a) evaluate validity and relative reliability of a single VAS compared to previously…

  15. Cyclone energy: impact of inlet velocity and outlet évasé designs

    Science.gov (United States)

    Because electricity generation produces emissions, reducing cyclone pressure drop has the potential to benefit the environment. Enhanced 1D3D cyclones common in the cotton ginning industry were tested with various évasés, over a range of inlet velocities. With évasés it was possible to reduce the ...

  16. Excitatory and inhibitory effects of opiates in the rat vas deferens: a dual mechanism of opiate action.

    Science.gov (United States)

    Jacquet, Y F

    1980-10-03

    Both natural (-)-morphine and its unnatural enantiomer (+)-morphine exert an excitatory action on electrically stimulated contractions of rat vas deferens. Preexposure to (-)-morphine results in cross-tolerance to the inhibitory action of beta-endorphin. (-)-Naloxone and its stereoisomer (+)-naloxone also exert an excitatory action, but only (-)-naloxone bocks the inhibtory action of beta-endorphin. Thus morphine exerts a dual action on a peripheral organ: one an inhibitory action mediated by the stereospecific endorphin receptor that is blocked stereospecifically by naloxone, the other an excitatory action mediated by a nonstereospecific receptor that is not blocked by naloxone. The opiate abstinence syndrome is seen as due to the unmasking of the excitatory action of opiates when its concomitant inhibitory influence is removed by selective blockade by naloxone or weakened by selective tolerance. The view that the rat vas deferens is devoid of morphine receptors is now seen as arising from a reverse example of morphine's dual action: the masking of the inhibitory action of morphine by its concomitant and more potent excitatory action.

  17. Computation of 2D vibroacoustic wave's dispersion for optimizing acoustic power flow in interaction with adaptive metacomposites

    Science.gov (United States)

    Collet, M.; Ouisse, M.; Ichchou, M.; Ohayon, R.

    2013-04-01

    This paper presents an integrated methodology for optimizing vibroacoustic energy flow in interaction between an adaptive metacomposite made of periodically distributed shunted piezoelectric material glued onto passive plate and open acoustic domain. The computation of interacting Floquet-Bloch propagators is also used to optimize vibroacoustic behavior. The main purpose of this work is first to propose a numerical methodology to compute the fluid-structure multi-modal wave dispersions. In a second step, optimization of electric circuit is used to control the acoustic power flow. 3D standard computation is used to confirm the efficiency of the designed metacomposite in terms of acoustic emissivity and absorption.

  18. Duplicate Vas Deferens Encountered during Inguinal Hernia Repair: A Case Report and Literature Review

    Directory of Open Access Journals (Sweden)

    Maxwell C. Breitinger

    2016-01-01

    Full Text Available Duplication of the vas deferens is a rare anomaly, defined as the presence of two distinct vasa deferentia within one spermatic cord, with only 28 cases reported worldwide since 1959. We report the case of a 63-year-old man with a duplicate vas deferens, presenting with abdominal pain from bowel obstruction secondary to incarcerated inguinal hernia. Spermatic cord dissection during hernioplasty revealed duplication of the vas deferens within the right spermatic cord. Doppler ultrasonography confirmed absence of waveforms in both vasa deferentia with arterial signal in the accompanying vessel. The hernia was repaired without complication. This report emphasizes recognition of duplicate vas deferens in avoiding iatrogenic injury and optimizing surgical outcome.

  19. Vibro-acoustic condition monitoring of Internal Combustion Engines: A critical review of existing techniques

    Science.gov (United States)

    Delvecchio, S.; Bonfiglio, P.; Pompoli, F.

    2018-01-01

    This paper deals with the state-of-the-art strategies and techniques based on vibro-acoustic signals that can monitor and diagnose malfunctions in Internal Combustion Engines (ICEs) under both test bench and vehicle operating conditions. Over recent years, several authors have summarized what is known in critical reviews mainly focused on reciprocating machines in general or on specific signal processing techniques: no attempts to deal with IC engine condition monitoring have been made. This paper first gives a brief summary of the generation of sound and vibration in ICEs in order to place further discussion on fault vibro-acoustic diagnosis in context. An overview of the monitoring and diagnostic techniques described in literature using both vibration and acoustic signals is also provided. Different faulty conditions are described which affect combustion, mechanics and the aerodynamics of ICEs. The importance of measuring acoustic signals, as opposed to vibration signals, is due since the former seem to be more suitable for implementation on on-board monitoring systems in view of their non-intrusive behaviour, capability in simultaneously capturing signatures from several mechanical components and because of the possibility of detecting faults affecting airborne transmission paths. In view of the recent needs of the industry to (-) optimize component structural durability adopting long-life cycles, (-) verify the engine final status at the end of the assembly line and (-) reduce the maintenance costs monitoring the ICE life during vehicle operations, monitoring and diagnosing system requests are continuously growing up. The present review can be considered a useful guideline for test engineers in understanding which types of fault can be diagnosed by using vibro-acoustic signals in sufficient time in both test bench and operating conditions and which transducer and signal processing technique (of which the essential background theory is here reported) could be

  20. Development and psychometric testing of the Visual Analogue Scale for Irritable Bowel Syndrome (VAS-IBS).

    Science.gov (United States)

    Bengtsson, Mariette; Ohlsson, Bodil; Ulander, Kerstin

    2007-05-03

    The aim of this study was to develop and psychometrically test a short, patient-reported questionnaire to be used in clinical practice for patients with Irritable Bowel Syndrome (IBS). The Visual Analogue Scale for Irritable Bowel Syndrome (VAS-IBS) questionnaire was designed to measure the treatment response of symptoms and well-being in patients suffering from IBS. The VAS-IBS was psychometrically tested for content and criterion validity, scale acceptability, item-reduction, internal reliability consistency, simplicity, and speed. Two samples were used. One expert panel (five physicians and four registered nurses), who gave their opinion on the content validity, and one of 71 patients with IBS (mean age 38 years SD +13, range 19-65), who completed the VAS-IBS, as well as the Gastrointestinal Symptom Rating Scale and the Psychological General Well-Being Index for criterion validity. The items in the VAS-IBS capture the main physical concerns women with IBS might present and the psychometric testing confirmed that the VAS-IBS is an acceptable homogeneous patient-reported questionnaire indicated by Cronbach's alpha internal consistency reliability coefficient, with a value of 0.85. All correlations to test the criterion validity performed by using Pearson's correlation test, were statistically significant (p VAS-IBS is easy to complete and unproblematic to calculate. The VAS-IBS appears to be reliable and user-friendly, for patients as well as for health professionals. The final version of the VAS-IBS including nine items needs to be further tested in clinical practice cross-culturally in women as well as in men.

  1. Development and psychometric testing of the Visual Analogue Scale for Irritable Bowel Syndrome (VAS-IBS)

    OpenAIRE

    Ohlsson Bodil; Bengtsson Mariette; Ulander Kerstin

    2007-01-01

    Abstract Background The aim of this study was to develop and psychometrically test a short, patient-reported questionnaire to be used in clinical practice for patients with Irritable Bowel Syndrome (IBS). The Visual Analogue Scale for Irritable Bowel Syndrome (VAS-IBS) questionnaire was designed to measure the treatment response of symptoms and well-being in patients suffering from IBS. Methods The VAS-IBS was psychometrically tested for content and criterion validity, scale acceptability, it...

  2. The Visual Analogue WOMAC 3.0 scale - internal validity and responsiveness of the VAS version

    OpenAIRE

    Tennant Alan; White Peter J; Kersten Paula

    2010-01-01

    Abstract Background Many people suffer with Osteoarthritis (OA) and subsequent morbidity. Therefore, measuring outcome associated with OA is important. The Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) has been a widely used patient reported outcome in OA. However, there is relatively little evidence to support the use of the Visual Analogue Scale (VAS) version of the scale. We aimed to explore the internal validity and responsiveness of this VAS version of the WOMAC....

  3. Vibroacoustic flexural properties of symmetric honeycomb sandwich panels with composite faces

    Science.gov (United States)

    Guillaumie, Laurent

    2015-05-01

    The vibroacoustic bending properties of honeycomb sandwich panels with composite faces are studied from the wavenumber modulus to the mechanical impedance, passing through the modal density. Numerical results extracted from finite element software computations are compared with analytical results. In both cases, the homogenization method is used to calculate the global properties of the sandwich panel. Since faces are made of composite material, the classical laminate theory serves as reference. With particular conditions used in the application for symmetric panels, the original orthotropic mechanical properties can be reduced simply to three parameters commonly used in vibroacoustic characterizations. These three parameters are the mass per unit area, the bending rigidity and the out-of-plane shear rigidity. They simultaneously govern the wavenumber modulus, the modal frequencies, the modal density and the mechanical impedance. For all of these vibroacoustic characterizations, a special frequency called the transition frequency separates two domains. In the first domain, below the transition frequency or for low frequencies, the orthotropic sandwich panel has a classical isotropic plate behavior. In the second domain, above the transition frequency or for high frequencies, the out-of-plane shear rigidity is very significant and changes the behavior. However, the results discussed are only valid up to a certain frequency which is determined by the thickness and out-of-plane shear stiffness of the honeycomb core, the thickness and the bending stiffness of the laminated face sheets and then the mass per unit area and bending stiffness of the total sandwich structure. All these parameters influence the final choice of model and simplifications presented. Experimental measurements of the bending wavenumber modulus and modal frequencies for our own application were carried out. In the vibroacoustic domain, the critical frequency is also an important frequency. It again

  4. Eigensolutions to a vibroacoustic interior coupled problem with a perturbation method

    Science.gov (United States)

    Claude, Bertille; Duigou, Laetitia; Girault, Gregory; Cadou, Jean-Marc

    2017-02-01

    In this paper, an efficient and robust numerical method is proposed to solve non-symmetric eigenvalue problems resulting from the spatial discretization with the finite element method of a vibroacoustic interior problem. The proposed method relies on a perturbation method. Finding the eigenvalues consists in determining zero values of a scalar that depends on angular frequency. Numerical tests show that the proposed method is not sensitive to poorly conditioned matrices resulting from the displacement-pressure formulation. Moreover, the computational times required with this method are lower than those needed with a classical technique such as, for example, the Arnoldi method.

  5. Determining generalized indicator for vibroacoustic hazard at workplaces of mining machines

    Energy Technology Data Exchange (ETDEWEB)

    Rezniko, I.G.

    1986-10-01

    A method is presented for calculating vibroacoustic damage to operators which is based on measuring the noise and vibration levels which occur at the workplace. A value for this indicator is presented for several types of mining machines (e.g. drills, cutter loaders, excavators etc.). It is emonstrated that when an operator is subjected to the combined effect of hazardous factors, the permissible levels of noise and vibration should be 1 1/2 times lower than those established in health and safety standards. 6 references.

  6. Vibroacoustic Payload Environment Prediction System (VAPEPS): VAPEPS management center remote access guide

    Science.gov (United States)

    Fernandez, J. P.; Mills, D.

    1991-01-01

    A Vibroacoustic Payload Environment Prediction System (VAPEPS) Management Center was established at the JPL. The center utilizes the VAPEPS software package to manage a data base of Space Shuttle and expendable launch vehicle payload flight and ground test data. Remote terminal access over telephone lines to the computer system, where the program resides, was established to provide the payload community a convenient means of querying the global VAPEPS data base. This guide describes the functions of the VAPEPS Management Center and contains instructions for utilizing the resources of the center.

  7. Low-cost fiber Bragg grating vibroacoustic sensor for voice and heartbeat detection.

    Science.gov (United States)

    Tosi, Daniele; Olivero, Massimo; Perrone, Guido

    2008-10-01

    A fiber Bragg grating (FBG) vibroacoustic sensor exploiting an intensity-based interrogation principle is presented. The optical system is complemented by signal processing techniques that allow disturbances to be mitigated and improve the spectral estimation. The sensor is capable of performing frequency analysis of sounds up to 3 kHz, with top sensitivity in the 100-500 Hz frequency range, and of dynamically tracking pulsed phenomena that induce a strain to the FBG. The sensor has been applied to the detection of voice, showing a great intelligibility of the speech despite the low-quality environment, and to the monitoring of the heartbeat rate from the wrist.

  8. Vibroacoustic study of the NASA Goddard Space Flight Center OSS-1 payload

    Science.gov (United States)

    Lee, Y. A.; Henricks, W.

    1985-01-01

    A comparative evaluation of shuttle liftoff and ground test random response data obtained from the Office of Space Science-1 (OSS-1) pallet payload flown in the cargo bay of STS-3 is presented. The study was initiated to evaluate the possibility that the payload flight vibration response can exceed that occurred during ground test when the ground test acoustic excitation is normalized to the flight acoustic environment. In addition, the analytically derived response from the Vibroacoustic Payload Environment Prediction System (VAPEPS) is compared with OSS-1 ground test results.

  9. MINIMIZATION OF VIBROACOUSTIC EFFECTS AS A CRITERION FOR OPERATION OF GEAR TRANSMISSIONS IN ACCORDANCE WITH SUSTAINABLE DEVELOPMENT PRINCIPLES

    Directory of Open Access Journals (Sweden)

    Andrzej N. WIECZOREK

    2016-01-01

    Full Text Available In correctly functioning maintenance systems it is most important to prevent possible failures. A reduction of the vibroacoustic effects accompanying the operation of machines and equipment, including transmissions, is among the factors that lower the probability of a failure. The paper presents the results of the research on the impact of operational factors on vibroacoustic conditions of transmissions. The factors covered by the analysis included a change in the mating conditions of gear wheels associated with the wear of tooth surfaces, operation of transmissions in subharmonic conditions of the main resonance and the temperature of the lubricating oil. The study demonstrated that it was possible to reduce the vibroacoustic effects generated by gear transmissions by changing the conditions of their operation. Based on the results obtained, it has been found that the operation of gear transmissions in accordance with the sustainable development principles requires technical services to take active measures consisting in the search for optimal operating conditions in terms of the vibroacoustic conditions.

  10. Vibroacoustic analysis and experimental validation of the structural responses of NASA Mars Exploration Rover spacecraft due to acoustic launch load

    Science.gov (United States)

    Hwang, H. J.

    2003-01-01

    Structural responses of a spacecraft during liftoff are dominated by the intense acoustic pressure field imping on the exterior of the launch vehicle. Statistical Energy Analysis model of the NASA Mars Exploration Rover spacecraft has been developed and the SEA model was analyzed to predict vibroacoustic responses of the spacecraft under the diffuse acoustic loading condition.

  11. Fuzzy structure theory modeling of sound-insulation layers in complex vibroacoustic uncertain systems: theory and experimental validation.

    Science.gov (United States)

    Fernandez, Charles; Soize, Christian; Gagliardini, Laurent

    2009-01-01

    The fuzzy structure theory was introduced 20 years ago in order to model the effects of complex subsystems imprecisely known on a master structure. This theory was only aimed at structural dynamics. In this paper, an extension of that theory is proposed in developing an elastoacoustic element useful to model sound-insulation layers for computational vibroacoustics of complex systems. The simplified model constructed enhances computation time and memory allocation because the number of physical and generalized degrees of freedom in the computational vibroacoustic model is not increased. However, these simplifications introduce model uncertainties. In order to take into account these uncertainties, the nonparametric probabilistic approach recently introduced is used. A robust simplified model for sound-insulation layers is then obtained. This model is controlled by a small number of physical and dispersion parameters. First, the extension of the fuzzy structure theory to elastoacoustic element is presented. Second, the computational vibroacoustic model including such an elastoacoustic element to model sound-insulation layer is given. Then, a design methodology to identify the model parameters with experiments is proposed and is experimentally validated. Finally, the theory is applied to an uncertain vibroacoustic system.

  12. Modeling of micro-perforated panels in a complex vibro-acoustic environment using patch transfer function approach.

    Science.gov (United States)

    Maxit, L; Yang, C; Cheng, L; Guyader, J-L

    2012-03-01

    A micro-perforated panel (MPP) with a backing cavity is a well known device for efficient noise absorption. This configuration has been thoroughly studied in the experimental conditions of an acoustic tube (Kundt tube), in which the MPP is excited by a normal incident plane wave in one dimension. In a more practical situation, the efficiency of MPP may be influenced by the vibro-acoustic behavior of the surrounding systems as well as excitation. To deal with this problem, a vibro-acoustic formulation based on the patch transfer functions (PTF) approach is proposed to model the behavior of a micro-perforated structure in a complex vibro-acoustic environment. PTF is a substructuring approach, which allows assembling different vibro-acoustic subsystems through coupled surfaces. Upon casting micro-perforations and the flexibility of the MPP under transfer function framework, the proposed PTF formulation provides explicit representation of the coupling between subsystems and facilitates physical interpretation. As an illustration example, application to a MPP with a backing cavity located in an infinite baffle is demonstrated. The proposed PTF formulation is finally validated through comparison with experimental measurements available in the literature. © 2012 Acoustical Society of America

  13. Development and psychometric testing of the Visual Analogue Scale for Irritable Bowel Syndrome (VAS-IBS

    Directory of Open Access Journals (Sweden)

    Ohlsson Bodil

    2007-05-01

    Full Text Available Abstract Background The aim of this study was to develop and psychometrically test a short, patient-reported questionnaire to be used in clinical practice for patients with Irritable Bowel Syndrome (IBS. The Visual Analogue Scale for Irritable Bowel Syndrome (VAS-IBS questionnaire was designed to measure the treatment response of symptoms and well-being in patients suffering from IBS. Methods The VAS-IBS was psychometrically tested for content and criterion validity, scale acceptability, item-reduction, internal reliability consistency, simplicity, and speed. Two samples were used. One expert panel (five physicians and four registered nurses, who gave their opinion on the content validity, and one of 71 patients with IBS (mean age 38 years SD +13, range 19–65, who completed the VAS-IBS, as well as the Gastrointestinal Symptom Rating Scale and the Psychological General Well-Being Index for criterion validity. Results The items in the VAS-IBS capture the main physical concerns women with IBS might present and the psychometric testing confirmed that the VAS-IBS is an acceptable homogeneous patient-reported questionnaire indicated by Cronbach's alpha internal consistency reliability coefficient, with a value of 0.85. All correlations to test the criterion validity performed by using Pearson's correlation test, were statistically significant (p Conclusion The VAS-IBS appears to be reliable and user-friendly, for patients as well as for health professionals. The final version of the VAS-IBS including nine items needs to be further tested in clinical practice cross-culturally in women as well as in men.

  14. The vibroacoustic response and sound absorption performance of multilayer, microperforated rib-stiffened plates

    Science.gov (United States)

    Zhou, Haian; Wang, Xiaoming; Wu, Huayong; Meng, Jianbing

    2017-10-01

    The vibroacoustic response and sound absorption performance of a structure composed of multilayer plates and one rigid back wall are theoretically analyzed. In this structure, all plates are two-dimensional, microperforated, and periodically rib-stiffened. To investigate such a structural system, semianalytical models of one-layer and multilayer plate structures considering the vibration effects are first developed. Then approaches of the space harmonic method and Fourier transforms are applied to a one-layer plate, and finally the cascade connection method is utilized for a multilayer plate structure. Based on fundamental acoustic formulas, the vibroacoustic responses of microperforated stiffened plates are expressed as functions of a series of harmonic amplitudes of plate displacement, which are then solved by employing the numerical truncation method. Applying the inverse Fourier transform, wave propagation, and linear addition properties, the equations of the sound pressures and absorption coefficients for the one-layer and multilayer stiffened plates in physical space are finally derived. Using numerical examples, the effects of the most important physical parameters—for example, the perforation ratio of the plate, sound incident angles, and periodical rib spacing—on sound absorption performance are examined. Numerical results indicate that the sound absorption performance of the studied structure is effectively enhanced by the flexural vibration of the plate in water. Finally, the proposed approaches are validated by comparing the results of stiffened plates of the present work with solutions from previous studies.

  15. The Vibro-Acoustic Modelling of Slab Track with Embedded Rails

    Science.gov (United States)

    VAN LIER, S.

    2000-03-01

    The application of concrete slab track in railways has certain advantages compared with conventional ballasted track, but conventional slab track structures generally produce more noise than ballasted track. For this reason a “silent slab track” has been developed in the Dutch ICES “Stiller Treinverkeer” project (silent railway traffic) by optimizing the track. In the design, the rails are embedded in a cork-filled elastomeric material. The paper discusses the vibro-acoustic modelling of this track using the simulation package “TWINS”, combined with finite element techniques. The model evaluates the one-third octave band sound power spectrum radiated by train wheels and track, and provides for a tool to optimize the track design. Three track types are compared using the vibro-acoustic model: an existing slab track with embedded UIC54 rails, a newly designed, acoustically optimized slab track with a less stiff rail embedded in a stiffer elastomere, and, as a reference, a ballasted track. The models of the existing tracks have been validated with measurements. Calculations indicate that the optimized slab track will emit between 4 and 6 dB(A) less noise than the ballasted track. The existing slab track produces between 1·5 and 3 dB(A) more noise than the ballasted track; this is caused by resonances in the elastomeric moulding material in the frequency range determining the dB(A)-level.

  16. Reconstruction of vibroacoustic responses of a highly nonspherical structure using Helmholtz equation least-squares method.

    Science.gov (United States)

    Lu, Huancai; Wu, Sean F

    2009-03-01

    The vibroacoustic responses of a highly nonspherical vibrating object are reconstructed using Helmholtz equation least-squares (HELS) method. The objectives of this study are to examine the accuracy of reconstruction and the impacts of various parameters involved in reconstruction using HELS. The test object is a simply supported and baffled thin plate. The reason for selecting this object is that it represents a class of structures that cannot be exactly described by the spherical Hankel functions and spherical harmonics, which are taken as the basis functions in the HELS formulation, yet the analytic solutions to vibroacoustic responses of a baffled plate are readily available so the accuracy of reconstruction can be checked accurately. The input field acoustic pressures for reconstruction are generated by the Rayleigh integral. The reconstructed normal surface velocities are validated against the benchmark values, and the out-of-plane vibration patterns at several natural frequencies are compared with the natural modes of a simply supported plate. The impacts of various parameters such as number of measurement points, measurement distance, location of the origin of the coordinate system, microphone spacing, and ratio of measurement aperture size to the area of source surface of reconstruction on the resultant accuracy of reconstruction are examined.

  17. Stochastic BEM for the Vibroacoustic Analysis of Three-Dimensional Structures

    Directory of Open Access Journals (Sweden)

    R. D'Amico

    2011-01-01

    Full Text Available Nowadays, extending the NVH prediction reliability to the whole frequency range is an attractive goal of vibroacoustics. Deterministic methodologies are well established for the low-frequency range, but, decreasing the wavelength, energy-based methods are necessary. In such a range, a crucial role is played by small perturbations which highly influence the response sensitivity. Moreover, taking into account these variations allows to make the product design more robust and even quicker. Introducing geometrical uncertainties within the classic BEM formulation allows to obtain the so-called stochastic BEM. As a result, the solution shows deterministic behaviour at low frequencies; decreasing the wavelength, the effect of the uncertainties smooths the response. Consequently, it is possible to obtain an averaged trend over the whole frequency range which asymptotically tends to the deterministic one. In this paper, we deal with three-dimensional acoustic SBEM. First, the formulation and its basic assumptions are presented. Secondly, they are applied to academic cases to show its potentialities in predicting vibroacoustic behaviour over a wide frequency range.

  18. Reconstruction of vibroacoustic fields in half-space by using hybrid near-field acoustical holography.

    Science.gov (United States)

    Zhao, Xiang; Wu, Sean F

    2005-02-01

    In this paper we examine the accuracy and efficiency of reconstructing the vibroacoustic quantities generated by a vibrating structure in half-space by using hybrid near-field acoustic holography (NAH) and modified Helmholtz equation least squares (HELS) formulations. In hybrid NAH, we combine modified HELS with an inverse boundary element method (IBEM) to reconstruct a vibroacoustic field. The main advantage of this approach is that the majority of the input data can be regenerated but not measured, thus the efficiency is greatly enhanced. In modified HELS, we expand the field acoustic pressure in terms of outgoing and incoming spherical waves and specify the corresponding expansion coefficients by solving a system of equations obtained by matching the assumed-form solution to the measured acoustic pressure. Here the system of equations is ill conditioned and Tikhonov regularization is implemented through singular value decomposition (SVD) and the generalized cross-validation (GCV) method. Numerical examples of a dilating and oscillating spheres and finite cylinder are demonstrated. Test results show that hybrid NAH can yield a more accurate reconstruction than does a modified HELS, but a modified HELS is more efficient than is hybrid NAH [Work supported by NSF].

  19. Numerical vibroacoustic analysis of plates with constrained-layer damping patches.

    Science.gov (United States)

    Loredo, Alexandre; Plessy, Arnaud; El Hafidi, Ali; Hamzaoui, Nacer

    2011-04-01

    A numerical vibroacoustic model that can manage multilayered plates locally covered with damping patches is presented. All the layers can have an on-axis orthotropic viscoelastic behavior. Continuity of displacements and transverse shear stresses at each interface is enforced, which permits to write the entire displacement field in function of the displacements of the--common--first layer, leading to a two-dimensional plate model. The problem is then discretized by Rayleigh-Ritz's method using a trigonometric basis that includes both sine and cosine functions in order to treat various boundary conditions. The excitation can be of mechanical kind (concentrated or distributed forces) or of acoustic kind (plane wave of any incidence, diffuse field, etc.). The model permits to compute different vibroacoustic indicators: the mean square velocity of the plate, the radiation efficiency, and the transmission loss. Comparisons between the present model and numerical results from literature or finite element computations show that the model gives good results in both mechanical and acoustical aspects. Then, a comparison of the effects of different distributions of patches is presented. The role of the surface covering rate is first discussed, followed by a study involving different geometries for the same surface covering rate.

  20. Solving the vibroacoustic equations of plates by minimization of error on a sample of observation points.

    Science.gov (United States)

    Collery, Olivier; Guyader, Jean-Louis

    2010-03-01

    In the context of better understanding and predicting sound transmission through heterogeneous fluid-loaded aircraft structures, this paper presents a method of solving the vibroacoustic problem of plates. The present work considers fluid-structure coupling and is applied to simply supported rectangular plates excited mechanically. The proposed method is based on the minimization of the error of verification of the plate vibroacoustic equation of motion on a sample of points. From sampling comes an aliasing effect; this phenomenon is described and solved using a wavelet-based filter. The proposed approach is validated in presenting very accurate results of sound radiation immersed in heavy and light fluids. The fluid-structure interaction appears to be very well described avoiding time-consuming classical calculations of the modal radiation impedances. The focus is also put on different samplings to observe the aliasing effect. As perspectives sound radiation from a non-homogeneous plate is solved and compared with reference results proving all the power of this method.

  1. A study of vibroacoustic coupling between a pump and attached water-filled pipes.

    Science.gov (United States)

    Li, Bilong; Hodkiewicz, Melinda; Pan, Jie

    2007-02-01

    This paper presents a model for the vibroacoustical behavior of a pump coupled with water-filled pipes. Coupling between (a) the pump and the inlet and outlet pipes, and (b) the pipe wall and the fluid contained in the pipe, is investigated through analytical modeling and numerical simulation. In the model, the pump is represented by a rigid body supported by multiple elastic mounts, and the inlet and outlet pipes by two semi-infinite water-filled pipes. The vibration characteristics of the coupled system under the excitation of mechanical forces and fluid-borne forces at the pump are calculated. The results enhance our understanding about how the input mechanical and fluid excitation energy at the pump is transmitted to the pipes and how to relate the piping vibroacoustical response to the excitations at the pump. This study assists in predicting dynamic stress in pipes for given excitations at the pump, and in developing methods to identify the nature (fluid or mechanical) of the excitation forces at the pump using the vibration and dynamic pressure measurements on the pump/pipe system.

  2. How the factoid of wind turbines causing 'vibroacoustic disease' came to be 'irrefutably demonstrated'.

    Science.gov (United States)

    Chapman, Simon; St George, Alexis

    2013-06-01

    In recent years, claims have proliferated in cyberspace that wind turbines cause a large variety of symptoms and diseases. One of these, "vibroacoustic disease" (VAD) is frequently mentioned. The aim of this study is to examine the quality of the evidence on how VAD came to be associated with wind turbine exposure by wind farm opponents. Searches of the web (Google advanced) and major research databases for papers on VAD and wind turbines. Self-citation analysis of research papers on VAD. Google returned 24,700 hits for VAD and wind turbines. Thirty-five research papers on VAD were found, none reporting any association between VAD and wind turbines. Of the 35 papers, 34 had a first author from a single Portuguese research group. Seventy-four per cent of citations to these papers were self-citations by the group. Median self-citation rates in science are around 7%. Two unpublished case reports presented at conferences were found asserting that VAD was "irrefutably demonstrated" to be caused by wind turbines. The quality of these reports was abject. VAD has received virtually no scientific recognition beyond the group who coined and promoted the concept. There is no evidence of even rudimentary quality that vibroacoustic disease is associated with or caused by wind turbines. The claim that wind turbines cause VAD is a factoid that has gone 'viral' in cyberspace and may be contributing to nocebo effects among those living near turbines. © 2013 The Authors. ANZJPH © 2013 Public Health Association of Australia.

  3. Vibro-Acoustic Numerical Analysis for the Chain Cover of a Car Engine

    Directory of Open Access Journals (Sweden)

    Enrico Armentani

    2017-06-01

    Full Text Available In this work, a vibro-acoustic numerical and experimental analysis was carried out for the chain cover of a low powered four-cylinder four-stroke diesel engine, belonging to the FPT (FCA Power Train family called SDE (Small Diesel Engine. By applying a methodology used in the acoustic optimization of new FPT engine components, firstly a finite element model (FEM of the engine was defined, then a vibration analysis was performed for the whole engine (modal analysis, and finally a forced response analysis was developed for the only chain cover (separated from the overall engine. The boundary conditions applied to the chain cover were the accelerations experimentally measured by accelerometers located at the points of connection among chain cover, head cover, and crankcase. Subsequently, a boundary element (BE model of the only chain cover was realized to determine the chain cover noise emission, starting from the previously calculated structural vibrations. The numerical vibro-acoustic outcomes were compared with those experimentally observed, obtaining a good correlation. All the information thus obtained allowed the identification of those critical areas, in terms of noise generation, in which to undertake necessary improvements.

  4. Vibroacoustic Impact on the Architectonic Heritage When Using Replicas of 16th Century Weapons.

    Science.gov (United States)

    Lloret, Angel Tomas; Sendra, Sandra; Lloret, Jaime; Del Rey, Romina; Louis Cereceda, Miguel

    2017-08-14

    The recreation of historical battles next to old buildings, walls, churches, fortifications or historical facades belonging to the historical heritage of a city, has always been a source of controversy and discussion. In the absence of a clear legislation about how these buildings can be affected by the use of blunderbusses and pyrotechnics, it is necessary to carry out practical experiments to test the effect of these celebrations on these buildings. For this reason, this paper presents a set of practical experiments where the vibroacoustic effect of using weapons such as blunderbusses and harquebuses is analyzed. To gather these measurements, we have used several sound level meters and 3-axis accelerometers placed on the facade of an old building. The tests have been carried out at the Moors and Christians festival of Villajoyosa (Spain) which is internationally famous for this festival. In order to carry out the tests, six harquebusiers shot their firearms and the sensors placed along the facade of the building at different height collected the data. The results of these devices allow us to study the vibroacoustic impact on the facade depending on the height.

  5. Vibro-Acoustic Modulation Based Damage Identification in a Composite Skin-Stiffener Structure

    Science.gov (United States)

    Ooijevaar, T. H.; Loendersloot, R.; Rogge, M. D.; Akkerman, R.; Tinga, T.

    2014-01-01

    The vibro-acoustic modulation method is applied to a composite skin-stiffener structure to investigate the possibilities to utilize this method for damage identification in terms of detection, localisation and damage quantification. The research comprises a theoretical part and an experimental part. An impact load is applied to the skin-stiffener structure, resulting in a delamination underneath the stiffener. The structure is interrogated with a low frequency pump excitation and a high frequency carrier excitation. The analysis of the response in a frequency band around the carrier frequency is employed to assess the damage identification capabilities and to gain a better understanding of the modulations occurring and the underlying physical phenomena. Though vibro-acoustic is shown to be a sensitive method for damage identification, the complexity of the damage, combined with a high modal density, complicate the understanding of the relation between the physical phenomena and the modulations occurring. more research is recommended to reveal the physics behind the observations.

  6. Vibroacoustic response of panels under diffuse acoustic field excitation from sensitivity functions and reciprocity principles.

    Science.gov (United States)

    Marchetto, Christophe; Maxit, Laurent; Robin, Olivier; Berry, Alain

    2017-06-01

    This paper aims at developing an experimental method to characterize the vibroacoustic response of a panel to a diffuse acoustic field (DAF) excitation with a different laboratory setup than those used in standards (i.e., coupled rooms). The proposed methodology is based on a theoretical model of the DAF and on the measurement of the panel's sensitivity functions, which characterize its vibroacoustic response to wall plane waves. These functions can be estimated experimentally using variations of the reciprocity principle, which are described in the present paper. These principles can either be applied for characterizing the structural response by exciting the panel with a normal force at the point of interest or for characterizing the acoustic response (radiated pressure, acoustic intensity) by exciting the panel with a monopole and a dipole source. For both applications, the validity of the proposed approach is numerically and experimentally verified on a test case composed of a baffled simply supported plate. An implementation for estimating the sound transmission loss of the plate is finally proposed. The results are discussed and compared with measurements performed in a coupled anechoic-reverberant room facility following standards.

  7. Active vibration and noise control of vibro-acoustic system by using PID controller

    Science.gov (United States)

    Li, Yunlong; Wang, Xiaojun; Huang, Ren; Qiu, Zhiping

    2015-07-01

    Active control simulation of the acoustic and vibration response of a vibro-acoustic cavity of an airplane based on a PID controller is presented. A full numerical vibro-acoustic model is developed by using an Eulerian model, which is a coupled model based on the finite element formulation. The reduced order model, which is used to design the closed-loop control system, is obtained by the combination of modal expansion and variable substitution. Some physical experiments are made to validate and update the full-order and the reduced-order numerical models. Optimization of the actuator placement is employed in order to get an effective closed-loop control system. For the controller design, an iterative method is used to determine the optimal parameters of the PID controller. The process is illustrated by the design of an active noise and vibration control system for a cavity structure. The numerical and experimental results show that a PID-based active control system can effectively suppress the noise inside the cavity using a sound pressure signal as the controller input. It is also possible to control the noise by suppressing the vibration of the structure using the structural displacement signal as the controller input. For an airplane cavity structure, considering the issue of space-saving, the latter is more suitable.

  8. Computational Vibroacoustics in Low- and Medium- Frequency Bands: Damping, ROM, and UQ Modeling

    Directory of Open Access Journals (Sweden)

    Roger Ohayon

    2017-06-01

    Full Text Available Within the framework of the state-of-the-art, this paper presents a summary of some common research works carried out by the authors concerning computational methods for the prediction of the responses in the frequency domain of general linear dissipative vibroacoustics (structural-acoustic systems for liquid and gas in the low-frequency (LF and medium-frequency (MF domains, including uncertainty quantification (UQ that plays an important role in the MF domain. The system under consideration consists of a deformable dissipative structure, coupled with an internal dissipative acoustic fluid including a wall acoustic impedance, and surrounded by an infinite acoustic fluid. The system is submitted to given internal and external acoustic sources and to prescribed mechanical forces. An efficient reduced-order computational model (ROM is constructed using a finite element discretization (FEM for the structure and the internal acoustic fluid. The external acoustic fluid is treated using a symmetric boundary element method (BEM in the frequency domain. All the required modeling aspects required for the analysis in the MF domain have been introduced, in particular the frequency-dependent damping phenomena and model uncertainties. An industrial application to a complex computational vibroacoustic model of an automobile is presented.

  9. The efficiency of neurometabolic therapy in the prevention of arterial hypertension in workers of vibroacoustic professions of aircraft enterprises

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    Сергій Геннадійович Сова

    2015-04-01

    Full Text Available The article is dedicated to the problem of arterial hypertension, including hypertensive crisis prevention in aircraft enterprises’ workers of vibroacoustic professions. The article studies the influence of neurometabolic pharmaceutical medicine Vinpocetine on the course and prognosis of hypertension.Methods. Using the routine methods of cardiac patients’ clinical study we examined 63 persons delivered in an emergency to the inpatient units of the occupational diseases clinics with the diagnosis of "uncomplicated hypertensive crisis." The main group includes aircraft enterprises’ workers of vibroacoustic professions (n = 31 who were administered according to a therapeutic complex scheme the neurometabolic medicine Vinpocetine at a dose of 30-40 mg per day. The control group consists of the workers (n = 32 who didn’t encounter with vibroacoustic factor during their working activity and didn’t get any neurometabolic medicines according to the complex scheme of treatment.Results. The survey results have demonstrated the comparability of working groups by age, sex, main modifiable factors of cardiovascular risk, hemodynamic characteristics and cognitive abilities. Introduction of Vinpocetine into the scheme of treatment of vibroacoustic professions’ workers made it possible to achieve more significant, compared to control, decrease in blood pressure and the rates of hypertensive crises recurrence in the long-term dynamics, as well as improvement in left ventricular diastolic function of the heart and the significant increase in the scale of cognitive function data at the fifth month of observation (p<0,05.Conclusions. Using Vinpocetine can significantly improve the course and prognosis of hypertension among aircraft enterprises’ workers of vibroacoustic professions

  10. Hypoosmotic swelling test in alpaca (Vicugna pacos spermatozoa recovered the vas deferens

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    Quispe HA

    2015-08-01

    Full Text Available The study objective was to evaluate the endosmotic reaction in 5 hypoosmotic solutions 100, 125, 150, 175 and 200 mOsm/l (HOS test incubated 5 and 15 minutes using alpaca sperm recovered the vas deferens. We used 5 male alpacas with the vas deferens surgically diverted, recovering sperm 10 times for each animal; the microscopic characteristics were evaluated with ISAS®. Information’s hipoosmotic test was analyzed with a factorial arrangement in a random one-way model, the correlation between endosmosis and percentages of motility and vitality was analyzed with Spearman correlation. There were no significant differences (p>0,05 in incubation times; highly significant differences (p 0,05was found to endosmosis with percentages of sperm motility and vitality; in conclusion, a 125 mOsm/l solution with 5 minutes of incubation is sufficient to perform the hipoosmotic test in alpaca spermatozoa recovered the vas deferens.

  11. An inhibition of post-ganglionic motor transmission in the mammalian vas deferens by D-lysergic acid diethylamide.

    Science.gov (United States)

    Ambache, N; Dunk, L P; Verney, J; Zar, M A

    1973-06-01

    1. Under certain conditions D-lysergic acid diethylamide (LSD), 10(-9)-10(-6) g/ml., exerted an immediate, prolonged and slowly reversible inhibitory effect upon the post-ganglionic motor transmission in desheathed guinea-pig vas deferens preparations.2. The most critical factor influencing this action of LSD appeared to be the train length. With short trains of less than 4 or 5 pulses the twitch inhibition produced by LSD was often total. With longer trains (5-20 pulses), the degree of inhibition declined with increase in train length. These results suggest the existence of two components in the motor response to post-ganglionic stimulation, distinguished by their susceptibility to LSD.3. The inhibition of the LSD-susceptible component was related to the dose of LSD in the range 10(-9)-10(-6) g/ml., reaching a maximum at 0.5-1 x 10(-6) g/ml. The response remnants elicited by trains of more than 5 pulses under these conditions could not be reduced further by a ten- to twenty-fold increase in LSD concentration to 10(-5) g/ml. and were in fact slightly potentiated.4. The inhibition of post-ganglionic motor transmission by LSD was not explicable on the basis of an alpha-adrenoceptor blockade because it was not associated with any reduction in motor responses to noradrenaline.5. The use of propranolol excluded mediation of the LSD-inhibition by beta-adrenoceptors.6. The LSD effect was not due to a non-specific smooth muscle depression because it was not associated with any reduction in motor responses to acetylcholine, ATP or bradykinin.7. The inhibitory effect of LSD on post-ganglionic transmission resembled that of noradrenaline in that it was antagonized by phentolamine; another alpha-adrenoceptor blocking agent, phenoxybenzamine, was less effective than phentolamine in this respect.8. The LSD-inhibition was obtained in preparations taken from reserpinized guinea-pigs.9. The inhibition of motor transmission in the vas deferens by LSD was confirmed in rats, Meriones

  12. An inhibition of post-ganglionic motor transmission in the mammalian vas deferens by D-lysergic acid diethylamide

    Science.gov (United States)

    Ambache, N.; Dunk, Linda P.; Verney, J.; Zar, M. Aboo

    1973-01-01

    1. Under certain conditions D-lysergic acid diethylamide (LSD), 10-9-10-6 g/ml., exerted an immediate, prolonged and slowly reversible inhibitory effect upon the post-ganglionic motor transmission in desheathed guinea-pig vas deferens preparations. 2. The most critical factor influencing this action of LSD appeared to be the train length. With short trains of less than 4 or 5 pulses the twitch inhibition produced by LSD was often total. With longer trains (5-20 pulses), the degree of inhibition declined with increase in train length. These results suggest the existence of two components in the motor response to post-ganglionic stimulation, distinguished by their susceptibility to LSD. 3. The inhibition of the LSD-susceptible component was related to the dose of LSD in the range 10-9-10-6 g/ml., reaching a maximum at 0·5-1 × 10-6 g/ml. The response remnants elicited by trains of more than 5 pulses under these conditions could not be reduced further by a ten- to twenty-fold increase in LSD concentration to 10-5 g/ml. and were in fact slightly potentiated. 4. The inhibition of post-ganglionic motor transmission by LSD was not explicable on the basis of an α-adrenoceptor blockade because it was not associated with any reduction in motor responses to noradrenaline. 5. The use of propranolol excluded mediation of the LSD-inhibition by β-adrenoceptors. 6. The LSD effect was not due to a non-specific smooth muscle depression because it was not associated with any reduction in motor responses to acetylcholine, ATP or bradykinin. 7. The inhibitory effect of LSD on post-ganglionic transmission resembled that of noradrenaline in that it was antagonized by phentolamine; another α-adrenoceptor blocking agent, phenoxybenzamine, was less effective than phentolamine in this respect. 8. The LSD-inhibition was obtained in preparations taken from reserpinized guinea-pigs. 9. The inhibition of motor transmission in the vas deferens by LSD was confirmed in rats, Meriones shawii and

  13. Rat vas deferens SERCA2 is modulated by Ca{sup 2+}/calmodulin protein kinase II-mediated phosphorylation

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez, J.B.R.; Muzi-Filho, H. [Programa de Farmacologia e Inflamação, Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ (Brazil); Valverde, R.H.F. [Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ (Brazil); Quintas, L.E.M. [Programa de Farmacologia e Inflamação, Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ (Brazil); Noel, F. [Programa de Desenvolvimento de Fármacos, Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ (Brazil); Einicker-Lamas, M. [Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ (Brazil); Instituto Nacional de Ciência e Tecnologia em Biologia Estrutural e Bioimagem, Rio de Janeiro, RJ (Brazil); Cunha, V.M.N. [Programa de Farmacologia e Inflamação, Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ (Brazil)

    2013-03-19

    Ca{sup 2+} pumps are important players in smooth muscle contraction. Nevertheless, little information is available about these pumps in the vas deferens. We have determined which subtype of sarco(endo)plasmic reticulum Ca{sup 2+}-ATPase isoform (SERCA) is expressed in rat vas deferens (RVD) and its modulation by calmodulin (CaM)-dependent mechanisms. The thapsigargin-sensitive Ca{sup 2+}-ATPase from a membrane fraction containing the highest SERCA levels in the RVD homogenate has the same molecular mass (∼115 kDa) as that of SERCA2 from the rat cerebellum. It has a very high affinity for Ca{sup 2+} (Ca{sub 0.5} = 780 nM) and a low sensitivity to vanadate (IC{sub 50} = 41 µM). These facts indicate that SERCA2 is present in the RVD. Immunoblotting for CaM and Ca{sup 2+}/calmodulin-dependent protein kinase II (CaMKII) showed the expression of these two regulatory proteins. Ca{sup 2+} and CaM increased serine-phosphorylated residues of the 115-kDa protein, indicating the involvement of CaMKII in the regulatory phosphorylation of SERCA2. Phosphorylation is accompanied by an 8-fold increase of thapsigargin-sensitive Ca{sup 2+} accumulation in the lumen of vesicles derived from these membranes. These data establish that SERCA2 in the RVD is modulated by Ca{sup 2+} and CaM, possibly via CaMKII, in a process that results in stimulation of Ca{sup 2+} pumping activity.

  14. Validation of a visual analogue score (LRTI-VAS) in non-CF bronchiectasis.

    Science.gov (United States)

    Altenburg, Josje; Wortel, Kim; de Graaff, Casper S; van der Werf, Tjip S; Boersma, Wim G

    2016-03-01

    Quality of life in patients with non-cystic fibrosis (non-CF) bronchiectasis is largely defined by respiratory symptoms. To date, no disease-specific tool for symptom measurement in this patient group was available. We developed the lower respiratory tract infections - visual analogue scale (LRTI-VAS) in order to quickly and conveniently quantify symptoms in non-CF bronchiectasis. This study aimed to validate LRTI-VAS for use in non-CF bronchiectasis. This study included outpatients with radiologically proven bronchiectasis and no evidence of CF. Results of LRTI-VAS were compared with other markers of disease activity {lung function parameters, oxygen saturation and three health-related quality of life questionnaires [Medical Outcomes Study Short-Form 36 Health Survey (SF-36), St Georges Respiratory Questionnaire (SGRQ) and Leicester Cough Questionnaire (LCQ)]} and validity, reliability and responsiveness were assessed. Thirty stable and 30 exacerbating participants completed the LRTI-VAS questionnaire. When testing for repeatability on two separate occasions, no statistically significant difference between total scores was found {1.4 [standard deviation (SD)] 5.3}, P = 0.16). Internal consistency was high across items (Cronbach's alpha 0.86). Correlation with SGRQ, SF-36 and LCQ total scores was high. Following antibiotic treatment, mean (SD) LRTI-VAS total score improved from 18.1 (SD 9.9) to 26.1 (SD 6.6) (P VAS showed excellent validity, reliability and responsiveness to change and therefore appears a reliable tool for symptom measurement in non-CF bronchiectasis. © 2014 John Wiley & Sons Ltd.

  15. The use of acoustic stimulation to inspect the fetal mouth

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Keun Young; Jun, Hyun Ah; Jang, Pong Rheem; Lee, Keung Hee [Hallym University College of Medicine, Seoul (Korea, Republic of); Nagey, David A. [The Johns Hopkins University, Baltimore (United States)

    2000-12-15

    The normal neonatal response to sound stimulus consists of a generalized paroxysmal startle reflex. We recently noted an increase in fetal movements, head turning, mouth opening, tongue protrusion, cheek motion, hand to head movement and fetal eye blinking subsequent to fetal vibroacoustic stimulation. These movements are thought to represent portions of a startle response. Evaluation of the fetal face is an essential part of routine sonographic examination and of a level II examination. The complexity of the face in combination with suboptimal positioning may make it difficult to obtain adequate images of the fetal mouth. The fetal mouth is especially difficult to examine if it remains closed. It appeared to us that approximately 50% of the time, fetuses may be seen touching their face and head with their hands. This action may make evaluation of the face more difficult because of the shadowing caused by the overlying bones of the hands. We hypothesized that if vibroacoustic stimulation brings about fetal mouth movement and opening and/or withdrawal of the fetal hand from the mouth, it may facilitate anatomic evaluation for cleft lip and palate. Sonographic examination of the fetal mouth is facilitated if the mouth is open or moving. This study was designed to determine whether acoustic stimulation of the fetus would cause it to move its mouth. 109 women with uncomplicated pregnancies between 20 and 39 weeks gestation consented.

  16. A Randomized Controlled Trial of Auricular Transcutaneous Electrical Nerve Stimulation for Managing Posthysterectomy Pain

    Directory of Open Access Journals (Sweden)

    Hin Cheung Tsang

    2011-01-01

    Result. As compared to the baseline, only the true TENS group reported a significant reduction in VAS-rest (P=.001, VAS-huff (P=.004, and VAS-cough (P=.001, while no significant reduction in any of the VAS scores was seen in the sham TENS group (all P>.05. In contrast, a small rising trend was observed in the VAS-rest and VAS-huff scores of the control group, while the VAS-cough score remained largely unchanged during the period of the study. A between-group comparison revealed that all three VAS scores of the true TENS group were significantly lower than those of the control group at 15 and 30 minutes after the intervention (all P<.02. No significant between-group difference was observed in PEFR at any point in time. Conclusion. A single session of auricular TENS applied at specific therapeutic points significantly reduced resting (VAS-rest and movement-evoked pain (VAS-huff, VAS-cough, and the effects lasted for at least 30 minutes after the stimulation. The analgesic effects of auricular TENS appeared to be point specific and could not be attributed to the placebo effect alone. However, auricular TENS did not produce any significant improvement in the performance of PEFR.

  17. Volcanic alert system (VAS) developed during the 2011-2014 El Hierro (Canary Islands) volcanic process

    Science.gov (United States)

    García, Alicia; Berrocoso, Manuel; Marrero, José M.; Fernández-Ros, Alberto; Prates, Gonçalo; De la Cruz-Reyna, Servando; Ortiz, Ramón

    2014-06-01

    The 2011 volcanic unrest at El Hierro Island illustrated the need for a Volcanic Alert System (VAS) specifically designed for the management of volcanic crises developing after long repose periods. The VAS comprises the monitoring network, the software tools for analysis of the monitoring parameters, the Volcanic Activity Level (VAL) management, and the assessment of hazard. The VAS presented here focuses on phenomena related to moderate eruptions, and on potentially destructive volcano-tectonic earthquakes and landslides. We introduce a set of new data analysis tools, aimed to detect data trend changes, as well as spurious signals related to instrumental failure. When data-trend changes and/or malfunctions are detected, a watchdog is triggered, issuing a watch-out warning (WOW) to the Monitoring Scientific Team (MST). The changes in data patterns are then translated by the MST into a VAL that is easy to use and understand by scientists, technicians, and decision-makers. Although the VAS was designed specifically for the unrest episodes at El Hierro, the methodologies may prove useful at other volcanic systems.

  18. Feed-forward neural network model for hunger and satiety related VAS score prediction.

    Science.gov (United States)

    Krishnan, Shaji; Hendriks, Henk F J; Hartvigsen, Merete L; de Graaf, Albert A

    2016-07-07

    An artificial neural network approach was chosen to model the outcome of the complex signaling pathways in the gastro-intestinal tract and other peripheral organs that eventually produce the satiety feeling in the brain upon feeding. A multilayer feed-forward neural network was trained with sets of experimental data relating concentration-time courses of plasma satiety hormones to Visual Analog Scales (VAS) scores. The network successfully predicted VAS responses from sets of satiety hormone data obtained in experiments using different food compositions. The correlation coefficients for the predicted VAS responses for test sets having i) a full set of three satiety hormones, ii) a set of only two satiety hormones, and iii) a set of only one satiety hormone were 0.96, 0.96, and 0.89, respectively. The predicted VAS responses discriminated the satiety effects of high satiating food types from less satiating food types both in orally fed and ileal infused forms. From this application of artificial neural networks, one may conclude that neural network models are very suitable to describe situations where behavior is complex and incompletely understood. However, training data sets that fit the experimental conditions need to be available.

  19. Activation tagging of the two closely linked genes LEP and VAS independently affects vascular cell number

    DEFF Research Database (Denmark)

    van der Graaff, Eric; Hooykaas, Paul J J; Keller, Beat

    2002-01-01

    TISSUE SIZE (VAS) and LEP. These genes are closely linked and arranged in tandem. Activation tagging of LEP only caused a specific increase in the number of xylem cells. This increased xylem cell number, together with the ectopic leaf blade formation, indicates that LEP functions as a cell division...

  20. Proteomic analysis of androgen-regulated protein expression in a mouse fetal vas deferens cell line

    NARCIS (Netherlands)

    A. Umar (Arzu); T.M. Luider (Theo); C.A. Berrevoets (Cor); J.A. Grootegoed (Anton); A.O. Brinkmann (Albert)

    2003-01-01

    textabstractDuring sex differentiation, androgens are essential for development of the male genital tract. The Wolffian duct is an androgen-sensitive target tissue that develops into the epididymis, vas deferens, and seminal vesicle. The present study aimed to identify

  1. Removal of phosphorus from water by using volcanic ash soil (VAS): batch and column experiments.

    Science.gov (United States)

    Nguyen, Huy Van; Maeda, Morihiro

    2016-09-01

    Using low-cost and naturally available materials is considered an optimal adsorbent for removing phosphorus (P) from water due to its simplicity and economic efficiency. This study examined the removal of P from water using volcanic ash soil (VAS) by batch and column experiments. The maximum adsorption capacity of P was 2.94 mg g -1 , estimated from the batch experiment according to a Langmuir isotherm. The column study showed a higher adsorption capacity of 5.57 mg g -1 . The breakthrough curve showed that influent water containing 2 mg L -1 P was completely purified by VAS within 1,230 pore volumes (PV). The breakthrough and saturation points of the curves were 3,100 PV and 14,875 PV, respectively. After an adsorption column was loaded with 20,508 PV, a regeneration procedure was developed to determine whether an ion exchange of P with chloride occurred or adsorbed P in the columns could be eluted. Approximately 20% of P was recovered from columns by desorption tests, regardless of NaCl solution or deionized water. Specific surface area and mineral concentrations are both important characteristics that improve the adsorption capacity of VAS. The present study suggests that VAS is a promising adsorbent to remove P in water.

  2. Vibroacoustic Analysis of Cyclic Structures by Using Dof’s Size Reduction and Holographic Measurements

    Directory of Open Access Journals (Sweden)

    Abdelkhalak El Hami

    2006-01-01

    Full Text Available We propose a method for the vibroacoustic analysis of structures having symmetry properties. This method is based on the reduction of the number of the degrees of freedom involved (size reduction and the use of experimental data (confrontation numerical/experimental. We propose the extension of the method of the linear representations of finite symmetry groups to problems of coupling fluid-structure. This approach, while keeping the quality of the approximations, leads to a significant reduction of the number of degrees of freedom, with a maximal reduction for the so called repetitive structures. Finally, we present a practical case of modal analysis – in air and water – of a ship propeller formed by 3 stainless steel blades. The experimental results are obtained by using the whole-field, non-contact technique of electronic holography.

  3. Visual Attention Span and Optometric Conditions: Is There a Connection between a Poor VAS and an Optometric Diagnosis?

    Science.gov (United States)

    Carroll, Emily

    2004-01-01

    This paper investigates whether there is a correlation between a poor Visual Attention Span (VAS) and the child's optometric status. Convergence excess impacts most upon a male achieving a VAS-3 more than 75 per cent of the time. Fifty per cent of females with eye-teaming problems are unlikely to achieve a VAS-3 more than 25 per cent of the time.…

  4. Regularities of filtration of sunflower oil with the use of vibroacoustic exposure

    Directory of Open Access Journals (Sweden)

    S. A. Bredikhin

    2017-01-01

    Full Text Available The residue in sunflower oil is a dispersed phase consisting of particulate products grinding sunflower seeds in the form of particles of the pulp, oil cake, meal, residual quantities of metals, pesticides. In the recycling process they are in the oil in suspension and negatively affect its quality. For research an experimental setup was developed allowing to change the angle of inclination of the filter element. The regularities of filtration were determined without preliminary purification of sunflower oil by centrifugation and after centrifugation. It is established, the contamination of centrifuged oil in the initial period is 14.6 times lower. After 10 minutes of treatment, it decreases by 62%, after 20 minutes – by 79.4%. With a 30-minute treatment, particles of 0.005-0.1 mm in size are removed to 90%, which is approximated to the refined oil in terms of contamination. The influence of vibration-acoustic action on sunflower oil during its filtration is shown. At the last stage of production, the peroxide index is reduced to 2-3 moles of active oxygen, and after 3 months of storage – from 11.8 to 7.7, which according to GOST corresponds to the highest-grade oil. The regularities of the filtration without pre-treatment of sunflower oil by centrifugation and after centrifugation. Shows the effect of vibroacoustic exposure on sunflower oil when filtering. The obtained data on the change of qualitative parameters of sunflower oil during its filtration in the field of vibroacoustic impact.

  5. Initial Assessment of the Ares I-X Launch Vehicle Upper Stage to Vibroacoustic Flight Environments

    Science.gov (United States)

    Larko, Jeffrey M.; Hughes, William O.

    2008-01-01

    The Ares I launch vehicle will be NASA s first new launch vehicle since 1981. Currently in design, it will replace the Space Shuttle in taking astronauts to the International Space Station, and will eventually play a major role in humankind s return to the Moon and eventually to Mars. Prior to any manned flight of this vehicle, unmanned test readiness flights will be flown. The first of these readiness flights, named Ares I-X, is scheduled to be launched in April 2009. The NASA Glenn Research Center is responsible for the design, manufacture, test and analysis of the Ares I-X upper stage simulator (USS) element. As part of the design effort, the structural dynamic response of the Ares I-X launch vehicle to its vibroacoustic flight environments must be analyzed. The launch vehicle will be exposed to extremely high acoustic pressures during its lift-off and aerodynamic stages of flight. This in turn will cause high levels of random vibration on the vehicle's outer surface that will be transmitted to its interior. Critical flight equipment, such as its avionics and flight guidance components are susceptible to damage from this excitation. This study addresses the modelling, analysis and predictions from examining the structural dynamic response of the Ares I-X upper stage to its vibroacoustic excitations. A statistical energy analysis (SEA) model was used to predict the high frequency response of the vehicle at locations of interest. Key to this study was the definition of the excitation fields corresponding to lift off acoustics and the unsteady aerodynamic pressure fluctuations during flight. The predicted results will be used by the Ares I-X Project to verify the flight qualification status of the Ares I-X upper stage components.

  6. Intermittent ATP release from nerve terminals elicits focal smooth muscle Ca2+ transients in mouse vas deferens

    Science.gov (United States)

    Brain, Keith L; Jackson, V Margaret; Trout, Stephen J; Cunnane, Thomas C

    2002-01-01

    A confocal Ca2+ imaging technique has been used to detect ATP release from individual sympathetic varicosities on the same nerve terminal branch. Varicose nerve terminals and smooth muscle cells in mouse vas deferens were loaded with the Ca2+ indicator Oregon Green 488 BAPTA-1. Field (nerve) stimulation evoked discrete, focal increases in [Ca2+] in smooth muscle cells adjacent to identified varicosities. These focal increases in [Ca2+] have been termed ‘neuroeffector Ca2+ transients’ (NCTs). NCTs were abolished by α,β-methylene ATP (1 μM), but not by nifedipine (1 μM) or prazosin (100 nm), suggesting that NCTs are generated by Ca2+ influx through P2X receptors without a detectable contribution from L-type Ca2+ channels or α1-adrenoceptor-mediated pathways. Action potential-evoked ATP release was highly intermittent (mean probability 0.019 ± 0.002; range 0.001-0.10) at 1 Hz stimulation, even though there was no failure of action potential propagation in the nerve terminals. Twenty-eight per cent of varicosities failed to release transmitter following more than 500 stimuli. Spontaneous ATP release was very infrequent (0.0014 Hz). No Ca2+ transient attributable to noradrenaline release was detected even in response to 5 Hz stimulation. There was evidence of local noradrenaline release as the α2-adrenoceptor antagonist yohimbine increased the probability of occurrence of NCTs by 55 ± 21 % during trains of stimuli at 1 Hz. Frequency-dependent facilitation preferentially occurred at low probability release sites. The monitoring of NCTs now allows transmitter release to be detected simultaneously from each functional varicosity on an identified nerve terminal branch on an impulse-to-impulse basis. PMID:12068045

  7. CONCEPTION OF USE VIBROACOUSTIC SIGNALS AND NEURAL NETWORKS FOR DIAGNOSING OF CHOSEN ELEMENTS OF INTERNAL COMBUSTION ENGINES IN CAR VEHICLES

    Directory of Open Access Journals (Sweden)

    Piotr CZECH

    2014-03-01

    Full Text Available Currently used diagnostics systems are not always efficient and do not give straightforward results which allow for the assessment of the technological condition of the engine or for the identification of the possible damages in their early stages of development. Growing requirements concerning durability, reliability, reduction of costs to minimum and decrease of negative influence on the natural environment are the reasons why there is a need to acquire information about the technological condition of each of the elements of a vehicle during its exploitation. One of the possibilities to achieve information about technological condition of a vehicle are vibroacoustic phenomena. Symptoms of defects, achieved as a result of advanced methods of vibroacoustic signals processing can serve as models which can be used during construction of intelligent diagnostic system based on artificial neural networks. The work presents conception of use artificial neural networks in the task of combustion engines diagnosis.

  8. Vibroacoustic diagnostic monitoring of selected primary coolant circuit components of the Bohunice V-1 nuclear power plant

    Energy Technology Data Exchange (ETDEWEB)

    Bahna, J.; Jaros, I. (Forschungsinstitut fuer Kernkraftwerke, Jaslovske Bohunice (Czechoslovakia))

    1983-02-01

    An information is given about vibroacoustic monitoring systems installed at the two units of the Bohunice V-1 nuclear power plant for oscillation monitoring of the reactor coolant pumps and reactor pressure vessel. Signal processing and analysis techniques have been developed for diagnostic measurements. It is reported on some experience gained from oscillation measurements at the reactor coolant pumps of the V-1 nuclear power plant since commissioning of the plant.

  9. Circadian rhythm of glycoprotein secretion in the vas deferens of the moth, Spodoptera littoralis

    Directory of Open Access Journals (Sweden)

    Gvakharia B

    2002-09-01

    Full Text Available Abstract Background Reproductive systems of male moths contain circadian clocks, which time the release of sperm bundles from the testis to the upper vas deferens (UVD and their subsequent transfer from the UVD to the seminal vesicles. Sperm bundles are released from the testis in the evening and are retained in the vas deferens lumen overnight before being transferred to the seminal vesicles. The biological significance of periodic sperm retention in the UVD lumen is not understood. In this study we asked whether there are circadian rhythms in the UVD that are correlated with sperm retention. Results We investigated the carbohydrate-rich material present in the UVD wall and lumen during the daily cycle of sperm release using the periodic acid-Shiff reaction (PAS. Males raised in 16:8 light-dark cycles (LD showed a clear rhythm in the levels of PAS-positive granules in the apical portion of the UVD epithelium. The peak of granule accumulation occurred in the middle of the night and coincided with the maximum presence of sperm bundles in the UVD lumen. These rhythms persisted in constant darkness (DD, indicating that they have circadian nature. They were abolished, however, in constant light (LL resulting in random patterns of PAS-positive material in the UVD wall. Gel-separation of the UVD homogenates from LD moths followed by detection of carbohydrates on blots revealed daily rhythms in the abundance of specific glycoproteins in the wall and lumen of the UVD. Conclusion Secretory activity of the vas deferens epithelium is regulated by the circadian clock. Daily rhythms in accumulation and secretion of several glycoproteins are co-ordinated with periodic retention of sperm in the vas deferens lumen.

  10. A comparison of vas occlusion techniques: cautery more effective than ligation and excision with fascial interposition

    OpenAIRE

    Labrecque Michel; Chen-Mok Mario; Irsula Belinda; Sokal David; Barone Mark A

    2004-01-01

    Abstract Background Vasectomy techniques have been the subject of relatively few rigorous studies. The objective of this analysis was to compare the effectiveness of two techniques for vas occlusion: intraluminal cautery versus ligation and excision with fascial interposition. More specifically, we aimed to compare early failure rates, sperm concentrations, and time to success between the two techniques. Methods We compared semen analysis data from men following vasectomy using two occlusion ...

  11. Mitigating effects of Jambul against lead induced toxicity in epididymis and vas deferens of mice

    Directory of Open Access Journals (Sweden)

    Tahir Abbas

    2015-11-01

    Full Text Available Background: Precious fruits like jambul are neglected and wasted while environmental pollutants like lead intake remain overlooked. Objective: The aim of this study was to investigate the effects of the Jambul pulp extract on lead detrimental effects in pseudostratified epithelium and the stereocilia of mice epididymis and vas deferens. Materials and Methods: Thirty young males mice (Mus musculus were distributed randomly in 3 groups (n= 10 called control, Pb (Lead and Pb-J (Lead-Jambul. The Pb and Pb-J were provided 50ppm Pb in drinking water ad libitum for 15 days and Pb free water for the next 5 days. The Pb-J group received 0.2ml jambul pulp extract on 12 hourly bases. Control group was not given any treatment. Organs (epididymis and vas deference were recovered on 21st day after euthanasia. The organs were finally processed for histological and micrometric studies. Results: Marked histologic and micrometric changes in both organs were noted in Pb group. These include significant (P ≤ 0.05 decrease in cross sectional area of caput and cauda epididymis folding tubing along with evident alterations of their endothelial thickness. Prominent signs of apoptosis (vacuolations in the corpus pseudostratified endothelium and the destruction of stereocilia of the epididymis and vas deferens in Pb compared to control group were observed. Evident signs of recovery, in both organs, such as proliferation and rearrangements in pseudostratified endothelium and the stereocilia along with convincing recovery in micrometric parameters were observed in Pb-J group. Conclusion: The results indicate that epididymis and vas deferens are highly sensitive to Pb exposure while Jambul pulp extract has shown rich mitigating potentials against such histopathologies.

  12. Findings concerning testis, vas deference, and epididymis in adult cases with nonpalpable testes.

    Science.gov (United States)

    Sahin, Coskun; Kalkan, Mehmet; Yalcinkaya, Soner

    2011-01-01

    In this study, we aimed to state the relationship between testis, epididymis and vas deference, in adult cases with nonpalpable testis. Between January 1996 and December 2009, we evaluated 154 adult cases with nonpalpable testes. Mean age was 23 years (20-27 years). Explorations were performed by open inguinal incision, laparoscopy, and by inguinal incision and laparoscopy together on 22, 131 and 1 patient, respectively. Of all the unilateral cases, 32 were accepted as vanishing testis. In five of these cases, vas deference was ending inside the abdomen, and in the others, it was ending inside the scrotum. In the remaining 99 unilateral and 22 bilateral cases, 143 testes were found in total. Testes were found in the inguinal canal as atrophic in one case, at the right renal pedicle level with dysmorphic testis in one case, and anterior to the internal ring between the bladder and the common iliac vessels at a smaller than normal size in 119 cases. One (0.69%) case did not have epididymis. While epididymis was attached to the testis only at the head and tail locations in 88 (61.53%) cases, it was totally attached to the testis in 54 (37.76%) cases. There is an obviously high incidence rate of testis and vas deference anomalies, where epididymis is the most frequent one. In cases with abdominal testes, this rate is highest for high localised abdominal testes.

  13. Effects of long-term fluoxetine treatment on adrenergic plasticity in rat vas deferens

    Directory of Open Access Journals (Sweden)

    Cláudio Fontes Souza

    2014-12-01

    Full Text Available Chronic antidepressant administration increases neurotrophin levels in the central and peripheral nervous system, leading to an increase of neuronal sprouting, reestablishment of neural networks and neurotransmitter levels. Injured peripheral nerves regenerate at very slow rates. However, the recovery of the hypogastric nerve in rodents after injury is significantly improved with neurotrophin administration. Accordingly, our goal was to determine whether treatment with the antidepressant fluoxetine affects catecholamine levels and neuronal function, after surgical denervation of the rat vas deferens. Noradrenaline levels in the denervated vas deferens were higher in fluoxetine-treated animals than in the vehicle-treated group, as measured by high performance liquid chromatography. In functional studies of smooth muscle contraction, the responses induced by phenylephrine or ATP, as well as pre-synaptic α2-adrenoceptor reactivity, were not modified by chronic treatment with the antidepressant. However, the contraction mediated by neuronal release of noradrenaline induced by tyramine was increased on days 7 and 21 after denervation in rats treated with fluoxetine. These data indicate that fluoxetine can improve functional recovery after rat vas deferens denervation.

  14. Mechanisms involved in nicotinic acetylcholine receptor-induced neurotransmitter release from sympathetic nerve terminals in the mouse vas deferens.

    Directory of Open Access Journals (Sweden)

    Damian J Williams

    Full Text Available Prejunctional nicotinic acetylcholine receptors (nAChRs amplify postganglionic sympathetic neurotransmission, and there are indications that intraterminal Ca(2+ stores might be involved. However, the mechanisms by which nAChR activation stimulates neurotransmitter release at such junctions is unknown. Rapid local delivery (picospritzing of the nAChR agonist epibatidine was combined with intracellular sharp microelectrode recording to monitor spontaneous and field-stimulation-evoked neurotransmitter release from sympathetic nerve terminals in the mouse isolated vas deferens. Locally applied epibatidine (1 µM produced 'epibatidine-induced depolarisations' (EIDs that were similar in shape to spontaneous excitatory junction potentials (SEJPs and were abolished by nonselective nAChR antagonists and the purinergic desensitizing agonist α,β-methylene ATP. The amplitude distribution of EIDs was only slightly shifted towards lower amplitudes by the selective α7 nAChR antagonists α-bungarotoxin and methyllcaconitine, the voltage-gated Na(+ channel blocker tetrodotoxin or by blocking voltage-gated Ca(2+ channels with Cd(2+. Lowering the extracellular Ca(2+ concentration reduced the frequency of EIDs by 69%, but more surprisingly, the Ca(2+-induced Ca(2+ release blocker ryanodine greatly decreased the amplitude (by 41% and the frequency of EIDs by 36%. Ryanodine had no effect on electrically-evoked neurotransmitter release, paired-pulse facilitation, SEJP frequency, SEJP amplitude or SEJP amplitude distribution. These results show that activation of non-α7 nAChRs on sympathetic postganglionic nerve terminals induces high-amplitude junctional potentials that are argued to represent multipacketed neurotransmitter release synchronized by intraterminal Ca(2+-induced Ca(2+ release, triggered by Ca(2+ influx directly through the nAChR. This nAChR-induced neurotransmitter release can be targeted pharmacologically without affecting spontaneous or electrically

  15. Vibroacoustic Modeling and Path Control of Air-Borne Axle Whine Noise

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    Dong Guo

    2014-08-01

    Full Text Available The axle whine noise will eventually affect the vehicle noise performance. In this study, a systematic modeling approach is developed to analyze the axle whine problem by considering the hypoid gear mesh from the tooth contact process as well as the system dynamics effect with gear design parameters and shaft-bearing-housing system taken into account. Moreover, the tuning of the dominant air-borne path is modeled analytically by using the sound transmission loss idea. First, gear tooth load distribution results are obtained in a 3-dimensional loaded tooth contact analysis program. Then mesh parameters are synthesized and applied to a linear multibody gear dynamic model to obtain dynamic mesh and bearing responses. The bearing responses are used as the excitation force to a housing finite element model. Finally, the vibroacoustic analysis of the axle is performed using the boundary element method; sound pressure responses in the axle surface are then simulated. Transmission losses of different panel partitions are included in the final stage to guide the tuning of air-borne paths to reduce the radiated axle whine noise. The proposed approach gives a more in-depth understanding of the axle whine generation and therefore can further facilitate the system design and trouble-shooting.

  16. Overview of the Orion Vibroacoustic Test Capability at NASA Glenn Research Center

    Science.gov (United States)

    Hughes, William O.; Hozman, Aron D.; McNelis, Mark E.; Otten, Kim D.

    2008-01-01

    In order to support the environmental test needs for our new Orion and Constellation program, NASA is developing unique world-class test facilities. To optimize this testing of spaceflight hardware while minimizing transportation issues, a one-stop, under one roof test capability is being developed at the Space Power Facility at the NASA Glenn Research Center's Plum Brook Station. This facility will provide the capability to perform the following environmental testing: (1) reverberation acoustic testing, (2) mechanical base-shake sine testing, (3) modal testing, (4) thermal-vacuum testing, and (5) EMI/EMC (electromagnetic interference and compatibility) testing. An overview of this test capability will be provided in this presentation, with special focus on the two new vibroacoustic test facilities currently being designed and built, the Reverberant Acoustic Test Facility (RATF) and the Mechanical Vibration Facility (MVF). Testing of the engineering developmental hardware and qualification hardware of the Orion (Crew Exploration Vehicle) will commence shortly after the facilities are commissioned.

  17. Vibroacoustic Optimization of Stiffening Ribs and Damping Material Distribution on Sheet Metal Parts

    Directory of Open Access Journals (Sweden)

    M. Carfagni

    2004-01-01

    Full Text Available Vehicle noise and vibration levels are basic parameters in passenger comfort. Both static and dynamic stiffness of sheet metal parts is commonly increased by means of stiffening ribs. Vibrations are also reduced by adding a layer of damping material on the floor, the roof, the firewall and other parts of the vehicle. In common practice the panels to be treated are ribbed according to criteria based on the designer’s experience, rather than on well defined design procedures and are uniformly covered by a layer of damping material. However, these are not efficient design solutions, especially with regard to the effectiveness of vibration reduction and to weight containment. In this paper a novel approach to achieve an optimal distribution of stiffening ribs and damping material will be presented. The proposed method is based on a Genetic Algorithm (G.A. procedure which takes into account both the vibroacoustic performance and the weight and cost reduction. A simple case study will be illustrated to demonstrate the capabilities of the developed procedure.

  18. Recovery of Biot's transition frequency of air-saturated poroelastic media using vibroacoustic spectroscopy

    Science.gov (United States)

    Ogam, Erick; Fellah, Z. E. A.

    2014-08-01

    The transition frequency marks the passage from low-frequency viscosity dominated flow to high-frequency inertia dominated one in porous media. It was one of the principal characteristics predicted by Biot's theory. The transition frequency has been a theoretical concept for which only theoretical expressions have been developed in recent years. A vibroacoustic spectroscopy experimental method to recover the characteristic frequency (fC) and for gaining insight into the frequency response of fluid-saturated porous materials has been developed. Long thin air-saturated porous rods solicited mechanically are employed for the experiment. Changes in the fluid flow profile with excitation frequency results in relative motion between the skeleton and the saturating-fluid. This enhances the frictional viscous forces, which, in turn, increases damping of the skeletal motion. These transitions are signaled by observable cues in the acquired laser-vibrometry spectrum of the rods' longitudinal vibration mode patterns. The resonance peaks exhibit sudden attenuation (increase in damping) and are interrupted at the transition frequencies evoking a change of propagation medium. These patterns are compared with those of two plains, single phase material (viscoelastic) rods whose modes stand out as regularly spaced moderately damped peaks.

  19. Analytical coupled vibroacoustic modeling of membrane-type acoustic metamaterials: Membrane model

    Science.gov (United States)

    Chen, Yangyang; Huang, Guoliang; Zhou, Xiaoming; Hu, Gengkai; Sun, Chin-Teh

    2014-09-01

    Membrane-type Acoustic Metamaterials (MAMs) have demonstrated unusual capacity in controlling low-frequency sound transmission/reflection. In this paper, an analytical vibroacoustic membrane model is developed to study sound transmission behavior of the MAM under a normal incidence. The MAM is composed of a prestretched elastic membrane with attached rigid masses. To accurately capture finite-dimension rigid mass effects on the membrane deformation, the point matching approach is adopted by applying a set of distributed point forces along the interfacial boundary between masses and the membrane. The accuracy and capability of the theoretical model is verified through the comparison with the finite element method. In particular, microstructure effects such as weight, size and eccentricity of the attached mass, pretension and thickness of the membrane on the resulting transmission peak and dip frequencies of the MAM are quantitatively investigated. New peak and dip frequencies are found for the MAM with one and multiple eccentric attached masses. The developed model can be served as an efficient tool for design of such membrane-type metamaterials.

  20. Analysis of vibroacoustic properties of dimpled beams using a boundary value model

    Science.gov (United States)

    Myers, Kyle R.

    Attention has been given recently to the use of dimples as a means of passively altering the vibroacoustic properties of structures. Because of their geometric complexity, previous studies have modeled dimpled structures using the finite element method. However, the dynamics of dimpled structures are not completely understood. The goal of this study is to provide a better understanding of these structures through the development of a boundary value model (BVM) using Hamilton's Variational Principle. The focus of this study is on dimpled beams, which represent the simplest form of a dimpled structure. A general model of a beam with N dimples in free vibration is developed. Since dimples formed via a stamping process do not change the mass of the beam, the dimple thickness is less than that of the straight segments. Differential equations of motion that describe the normal and axial motion of the dimpled beams are derived. Their numerical solution yields the natural frequencies and analytical mode shapes of a dimpled beam. The accuracy of this model is checked against those obtained using the finite element method, as well as the analytical studies on the vibrations of arches, and shown to be accurate. The effect of dimple placement, dimple angle, its chord length, its thickness, as well as beam boundary conditions on beam natural frequencies and mode shapes are investigated. For beams with axially restrictive boundary conditions, the results.

  1. Vibroacoustic Characterization of a New Hybrid Wing-Body Fuselage Concept

    Science.gov (United States)

    Allen, Albert R.; Przekop, Adam

    2012-01-01

    A lighter, more robust airframe design is required to withstand the loading inherent to next generation non cylindrical commercial airliners. The Pultruded Rod Stitched Efficient Unitized Structure concept, a highly integrated composite design involving a stitched and co-cured substructure, has been developed to meet such requirements. While this structure has been shown to meet the demanding out-of-plane loading requirements of the flat-sided pressurized cabin design, there are concerns that the stiff co-cured details will result in relatively high acoustic radiation efficiencies at frequencies well below the thin skin acoustic coincidence frequency. To address this concern and establish a set of baseline vibroacoustic characteristics, a representative test panel was fabricated and a suite of tests were conducted that involved measurements of panel vibration and radiated sound power during point force and diffuse acoustic field excitations. Experimental results are shown and compared with Finite Element and Statistical Energy Analysis model predictions through the use of modal and energy correlation techniques among others. The behavior of the structure subject to turbulent boundary layer excitation is also numerically examined.

  2. Vibroacoustic behavior of clamp mounted double-panel partition with enclosure air cavity.

    Science.gov (United States)

    Xin, F X; Lu, T J; Chen, C Q

    2008-12-01

    A theoretical study on the vibroacoustic performance of a rectangular double-panel partition clamp mounted in an infinite acoustic rigid baffle is presented. With the clamped boundary condition taken into account by the method of modal function, a double Fourier series solution to the dynamic response of the structure is obtained by employing the weighted residual method (i.e., the Galerkin method). The double series solution can be considered as the exact solution of the problem, as the structural and acoustic-structural coupling effects are fully accounted for and the solution converges numerically. The accuracy of the theoretical predictions is checked against existing experimental data, with good agreement achieved. The influence of several key parameters on the sound isolation capability of the double-panel configuration is then systematically studied, including panel dimensions, thickness of air cavity, elevation angle, and azimuth angle of incidence sound. The present method is suitable for double-panel systems of finite or infinite extent and is applicable for both low- and high-frequency ranges. With these merits, the proposed method compares favorably with a number of other approaches, e.g., finite element method, boundary element method, and statistical energy analysis method.

  3. Identification of material properties of orthotropic elastic cylinders immersed in fluid using vibroacoustic techniques.

    Science.gov (United States)

    Rosario, Daniel E; Brigham, John C; Aquino, Wilkins

    2008-11-01

    A numerical study is presented to show the potential for using vibroacoustic-based experiments to identify elastic material properties of orthotropic cylindrical vessels immersed in fluids. Sensitivity analyses and a simulated inverse problem are shown to quantify the potential for material characterization through the use of acoustic emissions. For comparison purposes, the analyses are also shown with the normal component of the velocity at the surface of the cylinder as the measured response in place of the acoustic pressure. The simulated experiment consisted of an orthotropic cylinder immersed in water with an impact force applied to the surface of the cylinder. The material parameters of the cylinder considered in the analyses were the circumferential and longitudinal elastic moduli, and the in-plane shear modulus. The velocity response is shown to provide sufficient information for characterizing all three moduli from a single experiment. Alternatively, the acoustic pressure response is shown to provide sufficient information for characterizing only the two elastic moduli from a single experiment. The analyses show that the acoustic pressure response does not have sufficient sensitivity to the in-plane shear modulus for characterization purposes.

  4. Increase in CD8+ and CD4+ T lymphocytes in patients with vibroacoustic disease.

    Science.gov (United States)

    Castro, A P; Aguas, A P; Grande, N R; Monteiro, E; Castelo Branco, N A

    1999-03-01

    Some workers employed by the aviation industry are exposed to large pressure amplitude and low frequency (LPALF) noise (> or =90 dB SPL, vibroacoustic disease (VAD), a whole-body noise-induced pathology. Since VAD patients have an increased prevalence of respiratory and skin infections, we investigated whether these individuals had any quantitative changes in the number of peripheral blood cell populations. Also, we investigated whether different types of noise environments are related to cell quantification. Quantification of peripheral blood cell populations was performed in venous blood samples of 34 VAD-diagnosed patients, and 41 controls. Leukocytes, monocytes, granulocytes, and surface phenotypes of CD8+ and CD4+ T lymphocytes were considered. We found that VAD patients showed a statistically significant elevation in the number of circulating CD8+ and CD4+ T lymphocytes when compared with the control population, but not when compared among different noise-environments. Monocyte and granulocyte populations did not register significant differences. VAD patients present enhancement in the number of circulating cytotoxic T lymphocytes (CD8+ and CD4+ T cells) thus indicating that this environmental disease is associated with quantitative changes in immune cells.

  5. Efficient modeling of flat and homogeneous acoustic treatments for vibroacoustic finite element analysis. Direct field formulations

    Science.gov (United States)

    Alimonti, L.; Atalla, N.

    2016-04-01

    This paper is concerned with the development of a simplified model for noise control treatments to speed up finite element analysis in vibroacoustic applications. The methodology relies on the assumption that the acoustic treatment is flat and homogeneous. Moreover, its finite lateral extent is neglected. This hypothesis is justified by short wavelength and large dissipation, which suggest that the reflected field emanating from the acoustic treatment lateral boundaries does not substantially affect its dynamic response. Under these circumstances, the response of the noise control treatment can be formally obtained by means of convolution integrals involving simple analytical kernels (i.e. Green functions). Such fundamental solutions can be computed efficiently by the transfer matrix method. However, some arbitrariness arises in the formulation of the mathematical model, resulting in different baffling conditions at the two ends of the treatment to be considered. Thus, the paper investigates the possibility of different formulations (i.e. baffling conditions) within the same hybrid finite element-transfer matrix framework, seeking for the best strategy in terms of tradeoff between efficiency and accuracy. Numerical examples are provided to show strengths and limitations of the proposed methodology.

  6. Vibroacoustics of the piano soundboard: Reduced models, mobility synthesis, and acoustical radiation regime

    CERN Document Server

    Boutillon, Xavier

    2013-01-01

    In string musical instruments, the sound is radiated by the soundboard, subject to the strings excitation. This vibration of this rather complex structure is described here with models which need only a small number of parameters. Predictions of the models are compared with results of experiments that have been presented in Ege et al. [Vibroacoustics of the piano soundboard: (Non)linearity and modal properties in the low- and mid- frequency ranges, Journal of Sound and Vibration 332 (5) (2013) 1288-1305]. The apparent modal density of the soundboard of an upright piano in playing condition, as seen from various points of the structure, exhibits two well-separated regimes, below and above a frequency flim that is determined by the wood characteristics and by the distance between ribs. Above flim, most modes appear to be localised, presumably due to the irregularity of the spacing and height of the ribs. The low-frequency regime is predicted by a model which consists of coupled sub-structures: the two ribbed ar...

  7. Analytical coupled vibroacoustic modeling of membrane-type acoustic metamaterials: membrane model.

    Science.gov (United States)

    Chen, Yangyang; Huang, Guoliang; Zhou, Xiaoming; Hu, Gengkai; Sun, Chin-Teh

    2014-09-01

    Membrane-type acoustic metamaterials (MAMs) have demonstrated unusual capacity in controlling low-frequency sound transmission/reflection. In this paper, an analytical vibroacoustic membrane model is developed to study sound transmission behavior of the MAM under a normal incidence. The MAM is composed of a prestretched elastic membrane with attached rigid masses. To accurately capture finite-dimension rigid mass effects on the membrane deformation, the point matching approach is adopted by applying a set of distributed point forces along the interfacial boundary between masses and the membrane. The accuracy and capability of the theoretical model is verified through the comparison with the finite element method. In particular, microstructure effects such as weight, size, and eccentricity of the attached mass, pretension, and thickness of the membrane on the resulting transmission peak and dip frequencies of the MAM are quantitatively investigated. New peak and dip frequencies are found for the MAM with one and multiple eccentric attached masses. The developed model can be served as an efficient tool for design of such membrane-type metamaterials.

  8. The Visual Analogue WOMAC 3.0 scale - internal validity and responsiveness of the VAS version

    Science.gov (United States)

    2010-01-01

    Background Many people suffer with Osteoarthritis (OA) and subsequent morbidity. Therefore, measuring outcome associated with OA is important. The Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) has been a widely used patient reported outcome in OA. However, there is relatively little evidence to support the use of the Visual Analogue Scale (VAS) version of the scale. We aimed to explore the internal validity and responsiveness of this VAS version of the WOMAC. Methods Patients with chronic hip or knee pain of mechanical origin, waiting for a hip or knee joint replacement completed the WOMAC as part of a study to investigate the effects of acupuncture and placebo controls. Validity was tested using factor analysis and Rasch analysis, and responsiveness using standardised response means. Results Two hundred and twenty one patients (mean age 66.8, SD 8.29, 58% female) were recruited. Factor and Rasch analysis confirmed unidimensional Pain and Physical Functioning scales, capable of transformation to interval scaling and invariant over time. Some Differential Item Functioning (DIF) was observed, but this cancelled out at the test level. The Stiffness scale fitted the Rasch model but adjustments for DIF could not be made due to the shortness of the scale. Using the interval transformed data, Standardised Response Means were smaller than when using the raw, ordinal data. Conclusions The WOMAC Pain and Physical Functioning subscales satisfied unidimensionality and ordinal scaling tests, and the ability to transform to an interval scale. Some Differential Item Functioning was observed, but this cancelled out at the test level and, by doing so, at the same time removed the disturbance of unidimensionality. The scaling characteristics of sets of items which use VAS require further analysis, as it would appear that they can lead to spurious levels of responsiveness and scale compression because they exaggerate the distortion of the ordinal scale. Trial

  9. The Visual Analogue WOMAC 3.0 scale - internal validity and responsiveness of the VAS version

    Directory of Open Access Journals (Sweden)

    Tennant Alan

    2010-04-01

    Full Text Available Abstract Background Many people suffer with Osteoarthritis (OA and subsequent morbidity. Therefore, measuring outcome associated with OA is important. The Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC has been a widely used patient reported outcome in OA. However, there is relatively little evidence to support the use of the Visual Analogue Scale (VAS version of the scale. We aimed to explore the internal validity and responsiveness of this VAS version of the WOMAC. Methods Patients with chronic hip or knee pain of mechanical origin, waiting for a hip or knee joint replacement completed the WOMAC as part of a study to investigate the effects of acupuncture and placebo controls. Validity was tested using factor analysis and Rasch analysis, and responsiveness using standardised response means. Results Two hundred and twenty one patients (mean age 66.8, SD 8.29, 58% female were recruited. Factor and Rasch analysis confirmed unidimensional Pain and Physical Functioning scales, capable of transformation to interval scaling and invariant over time. Some Differential Item Functioning (DIF was observed, but this cancelled out at the test level. The Stiffness scale fitted the Rasch model but adjustments for DIF could not be made due to the shortness of the scale. Using the interval transformed data, Standardised Response Means were smaller than when using the raw, ordinal data. Conclusions The WOMAC Pain and Physical Functioning subscales satisfied unidimensionality and ordinal scaling tests, and the ability to transform to an interval scale. Some Differential Item Functioning was observed, but this cancelled out at the test level and, by doing so, at the same time removed the disturbance of unidimensionality. The scaling characteristics of sets of items which use VAS require further analysis, as it would appear that they can lead to spurious levels of responsiveness and scale compression because they exaggerate the distortion of

  10. Orbit/attitude estimation for the GOES spacecraft using VAS landmark data

    Science.gov (United States)

    Sielski, H.; Hall, D.; Nankervis, R.; Koch, D.

    1980-01-01

    A software system is described which provides for batch least squares estimation of spacecraft orbit, attitude, and camera bias parameters using image data from the Geostationary Operational Environmental Satellites (GOES). The image data are obtained by the Visible and Infrared Spin Scan Radiometer (VISSR) Atmospheric Sounder (VAS). The resulting estimated parameters are used for absolute image registration. Operating in the Digital Equipment Corporation (DEC) PDP-11/70 computer, the FORTRAN system also includes the capabilities of image display and manipulations. An overview of the system is presented as well as some numerical results obtained from observations taken by the SMS-2 satellite over a 3 day interval in August 1975.

  11. Action of pro-opiomelanocortin products on the rat vas deferens.

    Science.gov (United States)

    Smock, T

    1986-11-03

    Behavioral study of pro-opiomelanocortin products indicates that beta-endorphin and corticotrophin-like peptides have antagonistic effects. However, these peptides have similar actions on the rat vas deferens. beta-endorphin, alpha-MSH and ACTH each inhibit electrically evoked contraction of the duct, but the corticotrophin derived peptides are tenfold more potent on a molar basis (ED50 = 9 nM). Pharmacological analysis shows that the action of corticotrophin-derived peptides does not involve an opiate receptor mechanism. The results are discussed in terms of the central action of the peptides.

  12. High correlation of VAS pain scores after 2 and 6 weeks of treatment with VAS pain scores at 12 weeks in randomised controlled trials in rheumatoid arthritis and osteoarthritis : meta-analysis and implications

    OpenAIRE

    Karabis, Andreas; Nikolakopoulos, Stavros; Pandhi, Shaloo; Papadimitropoulou, Katerina; Nixon, Richard; Chaves, Ricardo L.; Moore, R Andrew

    2015-01-01

    Background Researchers in clinical trials in rheumatoid arthritis (RA) and osteoarthritis (OA) often measure pain levels with a visual analogue scale (VAS). Of interest to clinical practice and future clinical trial design are associations of change from baseline (CFB) between time points with predictive ability of earlier response for long-term treatment benefit. We assessed the association and predictive ability of CFB in VAS pain between 2, 6 and 12?weeks in randomised controlled trials (R...

  13. System for vibroacoustic inspection of equipment in the first loop of an atomic electric power plant. [PWR

    Energy Technology Data Exchange (ETDEWEB)

    Samarin, A.A.; Krasyuk, V.Ya.; Ivanov, Yu.S.; Pospelko, A.A.

    1975-11-01

    A system is described for vibroacoustic inspection of equipment in the first loop of a nuclear power plant with water-moderated water-cooled power reactors. This monitoring system is now in operation at the Novovoronezh Power Plant. The installation performs the following functions: measurement and registration of effective and peak levels of structural noise and vibrations of the main technological equipment in the first loop; amplitude-frequency analysis of structural noises and vibration of equipment; (sound and light) signaling when the current noise level and vibration level exceed the present level; provides facilities for an operator to listen to structural noise of running equipment.

  14. Modeling of micro-perforated panels in a complex vibro-acoustic environment using patch transfer function approach

    OpenAIRE

    Maxit, Laurent; C. Yang; Cheng, Li; Guyader, Jean-Louis

    2012-01-01

    International audience; The micro-perforated panel (MPP) with a backing cavity is a well known efficient device for noise absorption. This device has been thoroughly studied in the experimental conditions of an acoustic tube (Kundt tube), in which the MPP is excited by a normal incident plane wave in one dimension. In an industrial situation, the efficiency of MPP may be influenced by the vibro-acoustic behaviour of the surrounding systems as well as excitation. To deal with this problem, a v...

  15. Testis and vas deferens morphology of the red-clawed mangrove tree crab (Goniopsis cruentata (Latreille, 1803

    Directory of Open Access Journals (Sweden)

    Garcia Tatiane Martins

    2006-01-01

    Full Text Available The present study describes the structure of the testes and vas deferens of the red-clawed mangrove tree crab, Goniopsis cruentata. Testes and vas deferens were fixed with cold Bouin's solution and submitted to histological routine examinations. Light microscopy showed the testis to be divided into three regions: anterior, containing the germinal zone; intermediary, including the collecting duct; and posterior. The vas deferens, which was continuous with the testes, could be divided into two regions: one corresponding to the expansions and another lined by cubical epithelium, collagenous fibers and a circular layer of muscle cells and containing the androgenic gland. Spermatophores were observed in both vas deferens regions suggesting that they participated in the maturation of the spermatozoids preparing the male functionally for fertilization.

  16. Three finger palpation technique of vas deferens for keyhole vasectomy in spotted (Axis axis) and sambar deer (Cervus unicolor)

    National Research Council Canada - National Science Library

    Open AccessResearch (Published online: --)

    2014-01-01

    .... A study was conducted to capture, neuter and release the deer with minimal hospitalization and stress by adopting three finger palpation technique of vas deferens and performing vasectomy through a key-hole incision...

  17. Three finger palpation technique of vas deferens for keyhole vasectomy in spotted (Axis axis and sambar deer (Cervus unicolor

    Directory of Open Access Journals (Sweden)

    B. J. William

    2014-09-01

    Full Text Available Aim: Vasectomy is performed in deer for population control, maintain pedigreed animals and prevent inbreeding. Conventional procedure of vasectomy required a long-term anesthesia and longer duration of hospitalization, which often result in stress, morbidity and mortality. A study was conducted to capture, neuter and release the deer with minimal hospitalization and stress by adopting three finger palpation technique of vas deferens and performing vasectomy through a key-hole incision. Materials and Methods: The study was conducted on three spotted male deer and three sambar male deer, which were immobilized with a mixture of xylazine at the dose of 1.00 mg/kg and ketamine at the dose of 5.00 mg/kg. The vas deferens could be palpated as a piece of cooked spaghetti at the neck of the scrotum on the anterior aspect by three finger palpation technique and was able to fix the vas deferens between the thumb and middle finger. Through a key-hole incision of <5 mm length, the vas deferens was exteriorized and resected using electrocautery and the skin incision was sealed with methyl methacrylate. The deer were released on the same day, and no post-operative complication was noticed. Conclusion: The study revealed that three finger palpation technique of vas deferens provided guidance for easy access to vas deferens for vasectomy in deer with less hospitalization, and the deer could be released on the same day.

  18. Visual analogue scale (VAS) as a monitoring tool for daily changes in asthma symptoms in adolescents: a prospective study.

    Science.gov (United States)

    Rhee, Hyekyun; Belyea, Michael; Mammen, Jennifer

    2017-01-01

    Success in asthma management hinges on patients' competency to detect and respond to ever-changing symptom severity. Thus, it is crucial to have reliable, simple, and sustainable methods of symptom monitoring that can be readily incorporated into daily life. Although visual analogue scale (VAS) has been considered as a simple symptom assessment method, its utility as a daily symptom monitoring tool in adolescents is unknown. This study was to determine the concurrent validity of VAS in capturing diurnal changes in symptoms and to examine the relationships between VAS and asthma control and pulmonary function. Forty-two adolescents (12-17 years old) with asthma completed daily assessment of symptoms twice per day, morning and bedtime, for a week using VAS and 6-item symptom diary concurrently. Asthma control was measured at enrollment and 6 month later, and spirometry was conducted at enrollment. Pearson correlations, multilevel modeling and regression were conducted to assess the relationships between VAS and symptom diary, asthma control and FEV1. Morning and evening VAS was positively associated with symptom diary items of each corresponding time frame of the day (r = 0.41-0.58, p monitoring, which can provide invaluable information about current and future asthma control without substantially increasing self-monitoring burdens for adolescent patients. Clinical Trial Registration NCT01696357. Registered 18 September 2012.

  19. The effects of Vibroacoustic treatment on girls and women with Rett Syndrome: Paper to the 2nd International Scientific Research Workshop: Infant Behaviour

    DEFF Research Database (Denmark)

    Wigram, Anthony Lewis

    2003-01-01

    Vibroacoustic therapy is a treatment using the relaxing effects of sedative music combined with pulsed, sinusoidal low frequency tones between 35Hz-70Hz, transmitted through bass speakers built into a bed or chair. This treatment has shown effects in reducing arousal level in girls and women with...... with Rett syndrome, and also reducing muscle tone....

  20. At Completion of a Multidisciplinary Treatment Program, Are Psychophysical Variables Associated with a VAS Improvement of 30% or More, a Minimal Clinically Important Difference, or an Absolute VAS Score Improvement of 1.5 cm or More?

    Science.gov (United States)

    Fishbain, David A; Gao, Jinrun; Lewis, John E; Zhang, Lei

    2016-04-01

    Objectives were to determine at completion of a multidisciplinary pain program: 1) what percentage of chronic low back pain (CLBP) patients had improved at 30% or more (minimal clinically important difference [MCID]) and by 1.5 cm or more (minimal important change [MIC]) on the visual analog scale (VAS) and 2) whether that improvement is associated with pain matching (PM), pain threshold (PTRE), and pain tolerance (PTOL) improvements. One hundred and six CLBP patients had admission and discharge scores for VAS, PM, PTRE, and PTOL. Improvement was determined by absolute, MCID, and MIC VAS improvement. Logistic regression analysis controlling for age, gender, race, education, psychoactive substance dependence, and depression was utilized to develop models for the dependent variables of improvement of overall VAS; of MCID of 50% or more; and of MIC with PM, PTOL, and PTRE as independent variables. Thirty-two percent and 35% of the CLBP patients were at MCID and MIC, respectively, at discharge (68% and 65% not at MCID and MIC, respectively), and 54.7% were improved overall. Of the improved patients, 59% were at MCID and 63.7% at MIC. PM was associated with overall VAS improvement, while PTRE and PM were associated with MCID improvement. MIC and 50% or above models could not be estimated. The VAS was treated as a ratio scale. A significant percentage of CLBP patients were at MCID and at MIC at completion of multidisciplinary treatment. PM was associated with overall VAS improvement, while PTRE and PM were associated with MCID. © 2015 American Academy of Pain Medicine. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  1. Comparison of Estimation Techniques for Vibro-Acoustic Transfer Path Analysis

    Directory of Open Access Journals (Sweden)

    Paulo Eduardo França Padilha

    2006-01-01

    Full Text Available Vibro-acoustic Transfer Path Analysis (TPA is a tool to evaluate the contribution of different energy propagation paths between a source and a receiver, linked to each other by a number of connections. TPA is typically used to quantify and rank the relative importance of these paths in a given frequency band, determining the most significant one to the receiver. Basically, two quantities have to be determined for TPA: the operational forces at each transfer path and the Frequency Response Functions (FRF of these paths. The FRF are obtained either experimentally or analytically, and the influence of the mechanical impedance of the source can be taken into account or not. The operational forces can be directly obtained from measurements using force transducers or indirectly estimated from auxiliary response measurements. Two methods to obtain the operational forces indirectly – the Complex Stiffness Method (CSM and the Matrix Inversion Method (MIM – associated with two possible configurations to determine the FRF – including and excluding the source impedance – are presented and discussed in this paper. The effect of weak and strong coupling among the paths is also commented considering the techniques previously presented. The main conclusion is that, with the source removed, CSM gives more accurate results. On the other hand, with the source present, MIM is preferable. In the latter case, CSM should be used only if there is a high impedance mismatch between the source and the receiver. Both methods are not affected by a higher or lower degree of coupling among the transfer paths.

  2. A three-dimensional vibroacoustic model for the prediction of underwater noise from offshore pile driving

    Science.gov (United States)

    Tsouvalas, A.; Metrikine, A. V.

    2014-04-01

    Steel monopiles are nowadays widely used as foundations for a large number of offshore structures. The installation procedure commonly involves a pile driving process which can last up to several hours depending upon pile dimensions, soil conditions and input energy of the hydraulic hammer. In impact pile driving, a hydraulic hammer delivers a series of hammer blows at the head of the pile that drive the pile into the sediment. Each hammer strike results in pile vibrations that emit strong impulsive sounds into the water column which can be harmful for the marine ecosystem. With today's increasing concern regarding the environmental impact of such operations, engineering tools which will be able to provide reliable predictions of the underwater noise levels are required. In this study, a linear semi-analytical formulation of the coupled vibroacoustics of a complete pile-water-soil interaction model is addressed. The pile is described by a high order thin shell theory whereas both water and soil are modelled as three-dimensional continua. Results obtained with the developed model indicate that the near-field response in the water column consists mainly of pressure conical waves generated by the supersonic compressional waves in the pile excited by the impact hammer. The soil response is dominated by shear waves with almost vertical polarization. The Scholte waves are also generated at the water-seabed interface which can produce pressure fluctuations in the water column that are particularly significant close to the sea floor. The effects of soil elasticity and pile size are thoroughly investigated and their influence on the generated pressure levels is highlighted. The results are also compared with those ones of a similar model in which the soil is treated as an equivalent acoustic fluid. It is shown that the latter approximation can yield inaccurate results at low frequencies especially for harder soil sediments.

  3. Vibroacoustic disease: biological effects of infrasound and low-frequency noise explained by mechanotransduction cellular signalling.

    Science.gov (United States)

    Alves-Pereira, Mariana; Castelo Branco, Nuno A A

    2007-01-01

    At present, infrasound (0-20 Hz) and low-frequency noise (20-500 Hz) (ILFN, 0-500 Hz) are agents of disease that go unchecked. Vibroacoustic disease (VAD) is a whole-body pathology that develops in individuals excessively exposed to ILFN. VAD has been diagnosed within several professional groups employed within the aeronautical industry, and in other heavy industries. However, given the ubiquitous nature of ILFN and the absence of legislation concerning ILFN, VAD is increasingly being diagnosed among members of the general population, including children. VAD is associated with the abnormal growth of extra-cellular matrices (collagen and elastin), in the absence of an inflammatory process. In VAD, the end-product of collagen and elastin growth is reinforcement of structural integrity. This is seen in blood vessels, cardiac structures, trachea, lung, and kidney of both VAD patients and ILFN-exposed animals. VAD is, essentially, a mechanotransduction disease. Inter- and intra-cellular communication is achieved through both biochemical and mechanotranduction signalling. When the structural components of tissue are altered, as is seen in ILFN-exposed specimens, the mechanically mediated signalling is, at best, impaired. Common medical diagnostic tests, such as EKG, EEG, as well as many blood chemistry analyses, are based on the mal-function of biochemical signalling processes. VAD patients typically present normal values for these tests. However, when echocardiography, brain MRI or histological studies are performed, where structural changes can be identified, all consistently show significant changes in VAD patients and ILFN-exposed animals. Frequency-specific effects are not yet known, valid dose-responses have been difficult to identify, and large-scale epidemiological studies are still lacking.

  4. A comparison of vas occlusion techniques: cautery more effective than ligation and excision with fascial interposition

    Directory of Open Access Journals (Sweden)

    Labrecque Michel

    2004-10-01

    Full Text Available Abstract Background Vasectomy techniques have been the subject of relatively few rigorous studies. The objective of this analysis was to compare the effectiveness of two techniques for vas occlusion: intraluminal cautery versus ligation and excision with fascial interposition. More specifically, we aimed to compare early failure rates, sperm concentrations, and time to success between the two techniques. Methods We compared semen analysis data from men following vasectomy using two occlusion techniques. Data on intraluminal cautery came from a prospective observational study conducted at four sites. Data on ligation and excision with fascial interposition came from a multicenter randomized controlled trial that evaluated the efficacy of ligation and excision with versus without fascial interposition. The surgical techniques used in the fascial interposition study were standardized. The surgeons in the cautery study used their customary techniques, which varied among sites in terms of type of cautery, use of fascial interposition, excision of a short segment of the vas, and use of an open-ended technique. Men in both studies had semen analyses two weeks after vasectomy and then approximately every four weeks. The two outcome measures for the analyses presented here are (a time to success, defined as severe oligozoospermia, or 10 million sperm/mL at week 12 or later. Results Vasectomy with cautery was associated with a significantly more rapid progression to severe oligozoospermia and with significantly fewer early failures (1% versus 5%. Conclusion The use of cautery improves vasectomy outcomes. Limitations of this comparison include (a the variety of surgical techniques in the cautery study and differences in methods of fascial interposition between the two studies, (b the uncertain correlation between sperm concentrations after vasectomy and the risk of pregnancy, and (c the use of historical controls and different study sites.

  5. Sampling Strategy for Soil Moisture Ground Measurements in the Campaigns of 2008 and 2009 at the Valencia Anchor Station (VAS)

    Science.gov (United States)

    Antolin, M. Carmen; Millan-Scheiding, Cristina; Carbo, Ester; Lopez-Baeza, Ernesto

    2010-12-01

    Knowledge of the distribution of soil moisture (SM) in semi-arid Mediterranean ecosystems, and of the environmental factors influencing it will enable the acquisition of in situ data simultaneous to the observations from SMOS in the area of the Valencia Anchor Station (VAS). In the Airborne Campaigns of 2008, 2009 and 2010 performed at the VAS site, different sample strategies have been followed with the objective of optimizing the work of acquisition of the necessary ground measurements for the validation of the airborne sensors and the relations with the environmental factors. The combined sampling designs used have enabled the estimation of SM values in larger areas, and the resulting SM maps are correlated with those produced by the airborne sensors. This confirms the use of these strategies for the calibration/validation of SMOS at the VAS.

  6. Multi-GPU and multi-CPU accelerated FDTD scheme for vibroacoustic applications

    Science.gov (United States)

    Francés, J.; Otero, B.; Bleda, S.; Gallego, S.; Neipp, C.; Márquez, A.; Beléndez, A.

    2015-06-01

    The Finite-Difference Time-Domain (FDTD) method is applied to the analysis of vibroacoustic problems and to study the propagation of longitudinal and transversal waves in a stratified media. The potential of the scheme and the relevance of each acceleration strategy for massively computations in FDTD are demonstrated in this work. In this paper, we propose two new specific implementations of the bi-dimensional scheme of the FDTD method using multi-CPU and multi-GPU, respectively. In the first implementation, an open source message passing interface (OMPI) has been included in order to massively exploit the resources of a biprocessor station with two Intel Xeon processors. Moreover, regarding CPU code version, the streaming SIMD extensions (SSE) and also the advanced vectorial extensions (AVX) have been included with shared memory approaches that take advantage of the multi-core platforms. On the other hand, the second implementation called the multi-GPU code version is based on Peer-to-Peer communications available in CUDA on two GPUs (NVIDIA GTX 670). Subsequently, this paper presents an accurate analysis of the influence of the different code versions including shared memory approaches, vector instructions and multi-processors (both CPU and GPU) and compares them in order to delimit the degree of improvement of using distributed solutions based on multi-CPU and multi-GPU. The performance of both approaches was analysed and it has been demonstrated that the addition of shared memory schemes to CPU computing improves substantially the performance of vector instructions enlarging the simulation sizes that use efficiently the cache memory of CPUs. In this case GPU computing is slightly twice times faster than the fine tuned CPU version in both cases one and two nodes. However, for massively computations explicit vector instructions do not worth it since the memory bandwidth is the limiting factor and the performance tends to be the same than the sequential version

  7. Vibroacoustics of the piano soundboard: Reduced models, mobility synthesis, and acoustical radiation regime

    Science.gov (United States)

    Boutillon, Xavier; Ege, Kerem

    2013-09-01

    In string musical instruments, the sound is radiated by the soundboard, subject to the strings excitation. This vibration of this rather complex structure is described here with models which need only a small number of parameters. Predictions of the models are compared with the results of experiments that have been presented in Ege et al. [Vibroacoustics of the piano soundboard: (non)linearity and modal properties in the low- and mid-frequency ranges, Journal of Sound and Vibration 332 (5) (2013) 1288-1305]. The apparent modal density of the soundboard of an upright piano in playing condition, as seen from various points of the structure, exhibits two well-separated regimes, below and above a frequency flim that is determined by the wood characteristics and by the distance between ribs. Above flim, most modes appear to be localised, presumably due to the irregularity of the spacing and height of the ribs. The low-frequency regime is predicted by a model which consists of coupled sub-structures: the two ribbed areas split by the main bridge and, in most cases, one or two so-called cut-off corners. In order to assess the dynamical properties of each of the subplates (considered here as homogeneous plates), we propose a derivation of the (low-frequency) modal density of an orthotropic homogeneous plate which accounts for the boundary conditions on an arbitrary geometry. Above flim, the soundboard, as seen from a given excitation point, is modelled as a set of three structural wave-guides, namely the three inter-rib spacings surrounding the excitation point. Based on these low- and high-frequency models, computations of the point-mobility and of the apparent modal densities seen at several excitation points match published measurements. The dispersion curve of the wave-guide model displays an acoustical radiation scheme which differs significantly from that of a thin homogeneous plate. It appears that piano dimensioning is such that the subsonic regime of acoustical

  8. High correlation of VAS pain scores after 2 and 6 weeks of treatment with VAS pain scores at 12 weeks in randomised controlled trials in rheumatoid arthritis and osteoarthritis : meta-analysis and implications

    NARCIS (Netherlands)

    Karabis, Andreas; Nikolakopoulos, Stavros; Pandhi, Shaloo; Papadimitropoulou, Katerina; Nixon, Richard; Chaves, Ricardo L; Moore, R Andrew

    2015-01-01

    BACKGROUND: Researchers in clinical trials in rheumatoid arthritis (RA) and osteoarthritis (OA) often measure pain levels with a visual analogue scale (VAS). Of interest to clinical practice and future clinical trial design are associations of change from baseline (CFB) between time points with

  9. [Experience with cardiac magnetic resonance imaging in patient management at the Markusovszky Hospital, Vas County, Hungary].

    Science.gov (United States)

    Major, Gyöngyi Petra; Halász, Szabolcs; Simor, Tamás; Németh, Orsolya; Pothárn, Orsolya; Nagy, Lajos

    2012-10-14

    At the Markusovszky Hospital, Vas County, Hungary, cardiac magnetic resonance imaging has been routinely used since July, 2009. In the majority of cases this method has been applied for the assessment of myocardial viability in patients with chronic ischemic heart disease and, in a smaller number of cases, for the evaluation of patients with myocarditis, cardiomyopathy and syncope with uncertain etiology in young athletes. The aim of the study was to analyze the clinical value of cardiac magnetic resonance imaging in assessing the viability of affected myocardial regions due to chronic occlusion of major coronary arteries. Delayed-enhancement cardiac magnetic resonance examination was performed in 88 patients who had 103 myocardial regions affected with chronic occlusion of the coronary arteries. The number of affected myocardial regions which proved to be treatable with coronary artery intervention and the number of regions where revascularization strategy was based on cardiac magnetic resonance imaging findings were analyzed. Based on findings from cardiac magnetic resonance imaging, revascularization strategy was set up in 88 myocardial regions corresponding to 83.5% of all affected myocardial regions included in this study. Delayed-enhancement cardiac magnetic resonance imaging appears to be a powerful tool to choose the optimal reperfusion strategy in patients with chronic coronary occlusion. Although this diagnostic method is relatively expensive, its accuracy regarding the features of myocardial viability such as transmural extension of the lesion within the affected region is higher than that of other methods (e.g. myocardium scintigraphy or stress echocardiography).

  10. Assessment of usefulness of amplitude-spectrum discriminants for vibroacoustic diagnosis of gearheads of shearer loaders with ranging arms

    Energy Technology Data Exchange (ETDEWEB)

    Sikora, W.; Zakrzewski, T.

    1985-01-01

    Use of vibration and acoustic measurement is analyzed for detection of failures and wear assessment of gearheads of the KWB-3RDU shearer loaders with shearer drums on ranging arms. Problems associated with selecting the optimum measuring points on the gearheads as well as measuring methods and methods for statistical analysis of measurement results are analyzed. Amplitude and frequency range of vibrations generated by the elements of mechanical transmissions in the gearheads are investigated. Use of amplitude-spectrum discriminants for analyzing vibroacoustic processes during idle running and shearer drum operation under conditions of nominal loading is evaluated. Analyses showed that vibration and acoustic measurements are an efficienct method for wear assessment and forecasting service life of gearheads of the KWB-3RDU shearer loaders. The gearheads with the maximum vibrations were characterized by the lowest service life and the highest failure probability. Loading increase caused vibration increase under conditions of idle running and nominal loading. 13 references.

  11. Vibro-Acoustic Analysis of Computer Disk Drive Components with Emphasis on Electro-Mechanical Noise Sources.

    Science.gov (United States)

    Lee, Ming-Ran

    Vibro-acoustic characteristics of compact electro -mechanical devices are not well understood. This study examines fundamental research issues in this area through the example case of a 3.5" personal computer hard disk drive. In particular, a narrow band mathematical model of the drive has been developed to predict prominent pure tones over the high frequency range (1-6.5 KHz). Through detailed analytical studies, it has been found that the motor torque pulsation of the brushless d.c. motor is the source for this noise problem. Accordingly, a simplified disk drive model consisting of motor driving a single disk is used to investigate key components, with emphasis on the development of new mathematical models to describe the source, path and radiator characteristics. Two different mathematical models have been developed for brushless d.c. motor to predict the torque spectrum associated with invertor switching logic, pulse width modulation control scheme, eccentricity, and magnetic saturation. Frequency contents of predicted variables are identified and matched with measured sound data. Additionally, the Galerkin's method (or modified harmonic balance) is also employed successfully to develop an efficient computational scheme which predicts the Fourier coefficients of torque pulsations directly including various effects associated with inductance harmonics and the fluctuation of rotor angular velocity. For the radiator (annular disk), modal base formulations of sound radiation have been developed by approximating disk eigen-functions. Specifically, the effects of modal coupling and source rotation on radiated sound are investigated. Analytical predictions match well with numerical results obtained by using a boundary element program. New mobility transfer functions (path) are derived to couple the source and radiator formulations in order to construct an overall vibro-acoustic model. Potential areas of further research including experimental validation are discussed.

  12. The Effects of Stretching with Lumbar Traction on VAS and Oswestry Scales of Patients with Lumbar 4–5 Herniated Intervertebral Disc

    OpenAIRE

    Yang, Hae-sun; Yoo, Won-gyu

    2014-01-01

    [Purpose] This study investigated the effect of stretching with lumbar traction on VAS and Oswestry scale scores of lumbar 4–5 herniated intervertebral disc (HIVD) patients. [Subjects] We recruited 20 lumbar 4–5 HIVD patients. [Methods] We performed stretching with lumbar traction for lumbar 4–5 HIVD patients during 4 weeks. The VAS and Oswestry scales were measured before and 4 weeks after the intervention. [Results] The results showed a significant decrease in VAS scale scores for stretchin...

  13. Visual analogue scales (VAS): Measuring instruments for the documentation of symptoms and therapy monitoring in cases of allergic rhinitis in everyday health care

    OpenAIRE

    Klimek, Ludger; Bergmann, Karl-Christian; Biedermann, Tilo; Bousquet, Jean; Hellings, Peter; Jung, Kirsten; Merk, Hans; Olze, Heidi; Schlenter, Wolfgang; Stock, Philippe; Ring, Johannes; Wagenmann, Martin; Wehrmann, Wolfgang; M?sges, Ralph; Pfaar, Oliver

    2017-01-01

    Backround Visual analogue scales (VAS) are psychometric measuring instruments designed to document the characteristics of disease-related symptom severity in individual patients and use this to achieve a rapid (statistically measurable and reproducible) classification of symptom severity and disease control. VAS can also be used in routine patient history taking and to monitor the course of a chronic disease such as allergic rhinitis (AR). More specifically, the VAS has been used to assess ef...

  14. Micro-endoscopy of the human vas deferens: a feasibility study of a novel device in several ex vivo models.

    Science.gov (United States)

    Trottmann, M; Sroka, R; Braun, C; Liedl, B; Schaaf, H; Graw, M; Becker, A J; Stief, C G; Khoder, W Y

    2017-01-01

    The aim of this study was to show limitation as well as potential of micro-endoscopy techniques as an innovative diagnostic and therapeutic approach in andrology. Two kinds of custom-made micro-endoscopes (ME) were tested in ex vivo vas deferens specimen and in post-mortem whole body. The semi-rigid ME included a micro-optic (0.9 mm outer diameter [OD], 10.000 pixels, 120° vision angle [VE], 3-20 mm field depth [FD]) and an integrated fibre-optic light source. The flexible ME was composed of a micro-optic (OD = 0.6 mm, 6.000 pixels, 120° VE, 3-20 mm FD). The ex vivo study included retrograde investigation of the vas deferens (surgical specimen n = 9, radical prostatectomy n = 3). The post-mortem investigation (n = 4) included the inspection of the vas deferens via both approaches. The results showed that antegrade and retrograde rigid endoscopy of the vas deferens were achieved as a diagnostic tool. The working channel enabled therapeutic use including biopsies or baskets. Using the flexible ME, the orifices of the ejaculatory ducts were identified. In vivo cadaveric retrograde cannulation of the orifices was successful. Post-mortem changes of verumontanum hindered the examinations beyond. Orifices were identified shaded behind a thin transparent membrane. Antegrade vasoscopy using flexible ME was possible up to the internal inguinal ring. Further advancement was impossible because of anatomical angle and lack adequate vision guidance. The vas deferens interior was clearly visible and was documented by pictures and movies. Altogether, the described ME techniques were feasible and effective, offering the potential of innovative diagnostic and therapeutic approaches for use in the genital tract. Several innovative indications could be expected. © 2016 American Society of Andrology and European Academy of Andrology.

  15. Correlation between CFTR gene mutations in Iranian men with congenital absence of the vas deferens and anatomical genital phenotype.

    Science.gov (United States)

    Radpour, Ramin; Gourabi, Hamid; Gilani, Mohamad Ali Sadighi; Dizaj, Ahmad Vosough

    2008-01-01

    Congenital bilateral absence of the vas deferens (CBAVD) and congenital unilateral absence of the vas deferens (CUAVD) are 2 causes of male sterility; these phenotypes are found in 1%-2% of men investigated for infertility and approximately 10% of men with azoospermia. To study the correlation between genital phenotype and cystic fibrosis genotype in men lacking at least 1 vas deferens, we evaluated the role of different CFTR gene mutations in the morphologic genital phenotype of 119 infertile men with bilateral or unilateral absence of the vas deferens (112 CBAVD and 7 CUAVD patients). Renal, scrotal, and transrectal ultrasonography were systematically performed. CFTR mutations and (TG)m(T)n polymorphism were analyzed, and epididymal and seminal vesicular abnormalities and testicular volume were compared among men with 2, 1, or no CFTR gene mutation, with or without the 5T allele. Our results showed that patients with CBAVD and renal agenesis have the same reproductive tract abnormalities as those with CUAVD, and reproductive tract abnormalities were independent of the subtypes of CFTR genotype in patients with absence of the vas deferens and CFTR gene mutations. Seminal vesicles did not differ between patients with or without CFTR gene mutation, but epididymal abnormalities were more frequent in CBAVD men without the mutation. Low testicular volume was observed in CBAVD men without the CFTR and IVS8-5T mutations, so we can hypothesize that a testicular factor (genetic or environmental) rather than CFTR gene mutations plays a role in determining the phenotype. Further studies using common diagnostic criteria are required to confirm our observations.

  16. A strategy for damage detection on large bearing constructions based on vibroacoustic signals. Ein Strategie zur Schadenserkennung an grossen Tragkonstruktionen auf vibroakustischer Signalbasis

    Energy Technology Data Exchange (ETDEWEB)

    Weber, A. (Akademie der Wissenschaften, Chemnitz (Germany))

    1991-01-01

    In the field of technical diagnosis analysis methods based on vibroacoustic signals are often used. Also modal system parameters can be used for the assessment of the bearing capacity of constructions. At present different institutes carry out research work in this area. Here the different approaches for the experimental determination of actual system parameters differ in the measuring technique as well as in the excitation mechanism used. The article gives a survey of the latest findings. (BWI).

  17. High correlation of VAS pain scores after 2 and 6 weeks of treatment with VAS pain scores at 12 weeks in randomised controlled trials in rheumatoid arthritis and osteoarthritis: meta-analysis and implications.

    Science.gov (United States)

    Karabis, Andreas; Nikolakopoulos, Stavros; Pandhi, Shaloo; Papadimitropoulou, Katerina; Nixon, Richard; Chaves, Ricardo L; Moore, R Andrew

    2016-03-31

    Researchers in clinical trials in rheumatoid arthritis (RA) and osteoarthritis (OA) often measure pain levels with a visual analogue scale (VAS). Of interest to clinical practice and future clinical trial design are associations of change from baseline (CFB) between time points with predictive ability of earlier response for long-term treatment benefit. We assessed the association and predictive ability of CFB in VAS pain between 2, 6 and 12 weeks in randomised controlled trials (RCTs) of non-steroidal anti-inflammatory drugs (NSAIDs). Aggregated VAS pain data at baseline and CFB at 2, 6 and 12 weeks were collected from a systematic literature review of 176 RCTs in OA and RA. The predictive ability of earlier assessments for longer-term pain reduction was estimated using correlation and regression analyses. Analysis was performed using the R software package for statistical programming, version 3.1.1. Appropriate data were available from 50 RCTs (22,854 patients). Correlations between time points were high (weighted correlation coefficients between 2 and 6 weeks, 0.84; between 2 and 12 weeks, 0.79; and between 6 and 12 weeks, 0.96). CFB at 6 weeks was highly predictive and close to CFB at 12 weeks (regression coefficient 0.9, 95 % confidence interval 0.9-1.0). CFB at 2 weeks was significantly associated with CFB at 12 (0.8, 0.7-0.8) and 6 weeks (0.9, 0.8-1.0). The results showed that early analgesic response measured by VAS for pain beyond 2 weeks of treatment with a particular NSAID is likely to be predictive of response at 12 weeks. Failure to achieve desired pain relief in OA and RA after 2 weeks should trigger reassessment of dosage and/or analgesic.

  18. A prospective cohort study comparing the VAS spine score and Roland-Morris disability questionnaire in patients with a type A traumatic thoracolumbar spinal fracture

    NARCIS (Netherlands)

    Siebenga, J.; Leferink, V.J.M.; Segers, M.J.M.; Elzinga, M.J.; Bakker, F.C.; Ten, D.H.J.; Rommens, P.M.; Patka, P.

    2008-01-01

    The Roland Morris Disability Questionnaire (RMDQ-24) and the VAS spine score have been regularly used to measure functional outcome in patients with back pain. The RMDQ-24 is primarily used in degenerative disease of the spine and the VAS Spine is used in trauma patients. The aim of this study is to

  19. Evaluation of Efficacy and Sedative Profiles of H1 Antihistamines by Large-Scale Surveillance Using the Visual Analogue Scale (VAS

    Directory of Open Access Journals (Sweden)

    Norimasa Izumi

    2008-01-01

    Conclusions: The sedative properties of the H1 antihistamines obtained from VAS analysis were very similar to those of H1R occupancy from positron emission tomography (PET studies and PIR from meta-analysis. Our results indicate that large-scale surveillance using VAS might be useful to evaluate the profiles of H1 antihistamines.

  20. A prospective cohort study comparing the VAS spine score and Roland-Morris disability questionnaire in patients with a type a traumatic thoracolumbar spinal fracture

    NARCIS (Netherlands)

    J.J. Siebenga (Joukje); V.J.M. Leferink (Vincent); M.J.M. Segers (Michiel); M.J. Elzinga (Matthijs); F.C. Bakker (Fred); D.H.J. ten Duis; P.M. Rommens (Pol); P. Patka (Peter)

    2008-01-01

    textabstractThe Roland Morris Disability Questionnaire (RMDQ-24) and the VAS spine score have been regularly used to measure functional outcome in patients with back pain. The RMDQ-24 is primarily used in degenerative disease of the spine and the VAS Spine is used in trauma patients. The aim of this

  1. Effect of on-site Coulomb interaction on electronic and transport properties of 100% spin polarized CoMnVAs

    Science.gov (United States)

    Bhat, Tahir Mohiuddin; Gupta, Dinesh C.

    2017-08-01

    The structural, electronic, magnetic and transport properties of a new quaternary Heusler alloy CoMnVAs have been investigated by employing generalized gradient approximation (GGA), modified Becke-Johnson (mBJ) and GGA with Hubbard U correction (GGA + U). The alloy is energetically more stable in ferromagnetic Y1 type structure. Elastic parameters reveal high anisotropy and ductile nature of the material. CoMnVAs shows half-metallic ferromagnet character with 100% spin polarization at Fermi level with band gap of 0.55 eV in the minority spin state. The alloy also possesses high electrical conductivity and Seebeck coefficients with 15 μVK-1 at room temperature, achieving a figure of merit of 0.65 at high temperatures. The high degree of ductility, 100% spin polarization and large Seebeck coefficient, makes it an attractive candidate to be used in spin voltage generators and thermoelectric materials.

  2. Visual analogue scale (VAS) as a monitoring tool for daily changes in asthma symptoms in adolescents: a prospective study

    OpenAIRE

    Rhee, Hyekyun; Belyea, Michael; Mammen, Jennifer

    2017-01-01

    Background Success in asthma management hinges on patients? competency to detect and respond to ever-changing symptom severity. Thus, it is crucial to have reliable, simple, and sustainable methods of symptom monitoring that can be readily incorporated into daily life. Although visual analogue scale (VAS) has been considered as a simple symptom assessment method, its utility as a daily symptom monitoring tool in adolescents is unknown. This study was to determine the concurrent validity of VA...

  3. Reliability and validity of observer ratings of pain using the visual analog scale (VAS) in infants undergoing immunization injections.

    Science.gov (United States)

    Taddio, Anna; O'Brien, Lisa; Ipp, Moshe; Stephens, Derek; Goldbach, Morton; Koren, Gideon

    2009-12-15

    We tested the reliability and validity of observer-rated pain in infants undergoing immunization using the visual analog scale (VAS). Pain was assessed in real time and later, from videotapes, in 120 1-year-old infants participating in a double-blind randomized controlled trial of amethocaine vs. placebo. Altogether, 2 (1 physician, 1 non-physician) of 4 raters [2 physicians, 2 non-physicians (nurse and graduate student)] independently assessed baseline and vaccine injection pain using a 100mm unmarked VAS line. Intra- and inter-rater reliability, assessed using the intra-class correlation coefficient (ICC), ranged from 0.69 to 0.91 and 0.55 to 0.97, respectively. Bland-Altman plots demonstrated no evidence of bias between real time and video assessments. When scores were dichotomized into 2 groups (no pain and pain) using a cut-off of >or=30mm, intra-rater reliability ranged from 0.35 to 0.92. The percent of scores deviating by >20mm was 4.5-14.29%. Criterion validity was demonstrated by correlations between the VAS and Modified Behavioural Pain Scale, a validated observational measure; (rho: 0.81-0.94). Injection scores were lower in the amethocaine group, when comparing difference (baseline-injection) or dichotomized scores; significance (pVAS as an outcome measure for acute procedural pain in infants. However, different conclusions may be reached about the effectiveness of analgesic interventions depending on the rater. Sources of variability include use of multiple raters, rater focus (procedure vs. child) and experience level.

  4. Sperm analysis of the vas deferens fluid after a long interval of unilateral percutaneous epididymal sperm aspiration in vasectomized patients

    Directory of Open Access Journals (Sweden)

    Fernando Lorenzini

    2013-09-01

    Full Text Available Objectives Evaluation of the presence of spermatozoa in vas deferens fluid after a long interval of unilateral and homolateral percutaneous epididymal sperm aspiration (PESA in vasectomized men. When found, the spermatozoa were evaluated including concentration and motility, in order to verify the patency of the epididymal tubules. Materials and Methods Four patients, numbered in a progressive order, from one to four, with 38, 40, 48 and 51 years old and vasectomy interval of 10, 10, 25 and 11 years, respectively, whose wives did not get pregnant using intracytoplasmic sperm injection of sperm obtained by unilateral PESA and decided to try only natural conception, were submitted to intrasurgical sperm analysis of the vas deferens fluid (ISAVDF during microsurgery for reconstruction of the seminal tract. Results Time interval between PESA and ISAVDF was 13.75 ± 11.12 months (x ± s varying from 3 to 29 months. Homolateral ISAVDF and PESA showed the presence of spermatozoa. Patients 1, 2 and 4 had a high concentration of 10 x 106, 64 x 106 and 45 x 106 spermatozoa/ mL; the first two had motile sperms and patient 3 had no sperms. Conclusions Three of four patients showed spermatozoa in the vas deferens fluid after a long interval of unilateral and homolateral PESA with high concentration, including motile forms. These findings support the concept that PESA may not result in late epipidymal tubule obstruction in vasectomized patients.

  5. Experimental characterization of a bi-dimensional array of negative capacitance piezo-patches for vibroacoustic control

    Science.gov (United States)

    Tateo, F.; Collet, M.; Ouisse, M.; Ichchou, M. N.; Cunefare, K. A.

    2013-04-01

    A recent technological revolution in the fields of integrated MEMS has finally rendered possible the mechanical integration of active smart materials, electronics and power supply systems for the next generation of smart composite structures. Using a bi-dimensional array of electromechanical transducers, composed by piezo-patches connected to a synthetic negative capacitance, it is possible to modify the dynamics of the underlying structure. In this study, we present an application of the Floquet-Bloch theorem for vibroacoustic power flow optimization, by means of distributed shunted piezoelectric material. In the context of periodically distributed damped 2D mechanical systems, this numerical approach allows one to compute the multi-modal waves dispersion curves into the entire first Brillouin zone. This approach also permits optimization of the piezoelectric shunting electrical impedance, which controls energy diffusion into the proposed semi-active distributed set of cells. Furthermore, we present experimental evidence that proves the effectiveness of the proposed control method. The experiment requires a rectangular metallic plate equipped with seventy-five piezo-patches, controlled independently by electronic circuits. More specifically, the out-of-plane displacements and the averaged kinetic energy of the controlled plate are compared in two different cases (open-circuit and controlled circuit). The resulting data clearly show how this proposed technique is able to damp and selectively reflect the incident waves.

  6. Automation of vibroacoustic data bank for random vibration criteria development. [for the space shuttle and launch vehicles

    Science.gov (United States)

    Ferebee, R. C.

    1982-01-01

    A computerized data bank system was developed for utilization of large amounts of vibration and acoustic data to formulate component random vibration design and test criteria. This system consists of a computer, graphics tablet, and a dry-silver hard copier which are all desk-top type hardware and occupy minimal space. The data bank contains data from the Saturn V and Titan III flight and static test programs. The vibration and acoustic data are stored in the form of power spectral density and one-third octave band plots over the frequency range from 20 to 2000 Hz. The data was stored by digitizing each spectral plot by tracing with the graphics tablet. The digitized data was statistically analyzed and the resulting 97.5% probability levels were stored on tape along with the appropriate structural parameters. Standard extrapolation procedures were programmed for prediction of component random vibration test criteria for new launch vehicle and payload configurations. This automated vibroacoustic data bank system greatly enhances the speed and accuracy of formulating vibration test criteria. In the future, the data bank will be expanded to include all data acquired from the space shuttle flight test program.

  7. Analysis of Vibroacoustic Modulations for Crack Detection: A Time-Frequency Approach Based on Zhao-Atlas-Marks Distribution

    Directory of Open Access Journals (Sweden)

    A. Trochidis

    2014-01-01

    Full Text Available The vibro-acoustic modulation (VAM technique is probably the most widely used nonlinear method for crack detection. The VAM method is based on the effect of modulation of high-frequency acoustic waves by a low-frequency vibration. The intensity of the modulation is related to the severity of the damage and has been used so far as a damage index. The damage index simply based on the amplitude of the first side bands in the spectral domain often leads to controversial results about the severity of the damage. In this work, the nonlinear characteristics of the vibro-modulation were systematically investigated by employing time-frequency analysis based on the Zhao-Atlas-Marks (ZAM distribution. The results of the analysis show that the amplitude of the sideband components is modulated by the low frequency vibration and the modulation amplitude depends on the size of the crack. Based on the obtained results, a new damage index was defined in relation to the strength of the modulation. The new damage index is more sensitive and robust and correlates better with crack size compared to the index based on the amplitude of the sidebands.

  8. A hybrid approach for predicting the distribution of vibro-acoustic energy in complex built-up structures.

    Science.gov (United States)

    Maksimov, Dmitrii N; Tanner, Gregor

    2011-09-01

    Finding the distribution of vibro-acoustic energy in complex built-up structures in the mid-to-high frequency regime is a difficult task. In particular, structures with large variation of local wavelengths and/or characteristic scales pose a challenge referred to as the mid-frequency problem. Standard numerical methods such as the finite element method (FEM) scale with the local wavelength and quickly become too large even for modern computer architectures. High frequency techniques, such as statistical energy analysis (SEA), often miss important information such as dominant resonance behavior due to stiff or small scale parts of the structure. Hybrid methods circumvent this problem by coupling FEM/BEM and SEA models in a given built-up structure. In the approach adopted here, the whole system is split into a number of subsystems that are treated by either FEM or SEA depending on the local wavelength. Subsystems with relative long wavelengths are modeled using FEM. Making a diffuse field assumption for the wave fields in the short wave length components, the coupling between subsystems can be reduced to a weighted random field correlation function. The approach presented results in an SEA-like set of linear equations that can be solved for the mean energies in the short wavelength subsystems. © 2011 Acoustical Society of America

  9. Experimental investigation of the influence of internal frames on the vibroacoustic behavior of a stiffened cylindrical shell using wavenumber analysis

    Science.gov (United States)

    Meyer, V.; Maxit, L.; Renou, Y.; Audoly, C.

    2017-09-01

    The understanding of the influence of non-axisymmetric internal frames on the vibroacoustic behavior of a stiffened cylindrical shell is of high interest for the naval or aeronautic industries. Several numerical studies have shown that the non-axisymmetric internal frame can increase the radiation efficiency significantly in the case of a mechanical point force. However, less attention has been paid to the experimental verification of this statement. That is why this paper proposes to compare the radiation efficiency estimated experimentally for a stiffened cylindrical shell with and without internal frames. The experimental process is based on scanning laser vibrometer measurements of the vibrations on the surface of the shell. A transform of the vibratory field in the wavenumber domain is then performed. It allows estimating the far-field radiated pressure with the stationary phase theorem. An increase of the radiation efficiency is observed in the low frequencies. Analysis of the velocity field in the physical and wavenumber spaces allows highlighting the coupling of the circumferential orders at the origin of the increase in the radiation efficiency.

  10. On a way to save memory when solving time domain boundary integral equations for acoustic and vibroacoustic applications

    Science.gov (United States)

    Thirard, Christophe; Parot, Jean-Marc

    2017-11-01

    Solving acoustic equations in the time domain, possibly coupled with the description of flexible structure dynamics, remains attractive as compared to solving the same in the frequency domain: this allows for better consideration of local non-linearities (acoustics/structure), and the boundary integral formulation (also known as BEM) offers an exact description of the infinite acoustic field based on a simple surface mesh (no need for 3D-volume discretization). Some issues remain however: the required memory space and computation time continue to grow rapidly when the number of elements of the surface mesh increases. In the case of a structure with a regular non-slender shape, the computational cost, measured in terms of required memory space, varies by Helmholtz number to the power of 4. This paper illustrates how the accelerating method called NGTD helps overcome this difficulty. This paper shows the applicability of 2 level NGTD to acoustic and vibroacoustic problems described solely by the hypersingular formulation for surfaces. It goes into more detail on some important aspects of the interpolation process and on the memory saving obtained. Implementation within the MOT (;March-On-Time;) ASTRYD code shows the benefits of this method. The memory requirement shows an estimated trend lower than power 1.35 of the number of surface elements.

  11. Evaluation of diagnostic thresholds dependability for tribologic signals received in the environment disturbed by vibroacoustic and functional signals

    Directory of Open Access Journals (Sweden)

    Lindstedt Paweł

    2015-12-01

    Full Text Available Determination of dependable diagnostic thresholds for tribologic signals received e.g. from antifriction bearings (in particular for insufficient number of measurements, only 4÷5 is a really difficult task due to complexity of working environment where such bearings are operated. Typical working environment for such objects must take account for operation time under various working conditions and accompanying (and disturbing signals, e.g. vibroacoustic ones. The sought assessment of the relationship between diagnostic signals and environmental noise can be determined from convolution of both diagnostic and environments signals that make up the complete set of received information. The convolution of these two series of signals can be obtained from an algorithm based on the Cauchy product. Then one has to find the coherence factor and the square of amplitude gain for the set of diagnostic signals with reference to various sets of signals received from environment, which makes it possible to evaluate cohesion of the investigated series of signals, thus their suitability to determine diagnostic threshold for tribologic signals intended for the analysis.

  12. The Erectile Function Visual Analog Scale (EF-VAS): a disease-specific utility instrument for the assessment of erectile function.

    Science.gov (United States)

    Casey, R; Tarride, J E; Keresteci, M A; Torrance, G W

    2006-04-01

    This article presents the responsiveness results of the Erectile Function Visual Analog Scale (EF-VAS) and reports, for the first time, utilities associated with erectile dysfunction (ED), as calculated by a disease-specific utility assessment. The EF-VAS is a new quality of life (QoL) instrument specific to ED that combines the strengths of the disease-specific approach to measuring QoL (greater disease relevance and responsiveness, with relevance to clinicians and patients) with those of preference-based assessments (generalizability and relevance to decision makers). The EF-VAS has demonstrated feasibility, reliability, and validity as reported in a recent publication. Standard instrument development methodology was utilized and the finalized content was integrated into a preference based scoring instrument comprised of two visual analogue scales (VAS). The EF-VAS was implemented in a clinical trial and data from the trial was subjected to validation analysis. Three methods were used to evaluate the responsiveness of the EF-VAS: Spearman correlations, effect size and standardized response means. VAS scores were converted to von Neumann-Morgenstern (vNM) utilities through a conversion curve. The EF-VAS was established to be responsive to changes in disease state within and between patients with ED. The EF-VAS allowed the calculation of vNM utility values and a significant increase in utility was observed in the sildenafil group compared to placebo at study end. The EF-VAS represents an important advance in the understanding of the impact of ED on patients' QoL and in providing a mechanism to allow the quantification of the health status that patients associate with ED. Based on its responsiveness, the EF-VAS will provide an important clinical tool to assess and contribute to the understanding of the impact of treatment for ED. The EF-VAS represents a major advance in the science of health-related quality of life (HRQol) assessment, as it is the first validated ED

  13. A prospective cohort study comparing the VAS spine score and Roland-Morris disability questionnaire in patients with a type a traumatic thoracolumbar spinal fracture

    OpenAIRE

    Siebenga, Joukje; Leferink, Vincent; Segers, Michiel; Elzinga, Matthijs; Bakker, Fred; Duis, D.H.J.; Rommens, Pol; Patka, Peter

    2008-01-01

    textabstractThe Roland Morris Disability Questionnaire (RMDQ-24) and the VAS spine score have been regularly used to measure functional outcome in patients with back pain. The RMDQ-24 is primarily used in degenerative disease of the spine and the VAS Spine is used in trauma patients. The aim of this study is to compare these scores and to see if there is a correlation in patients with a traumatic thoracolumbar spinal fracture. Prospective cohort study comparing the RMDQ-24 and the VAS spine s...

  14. Spinal Cord Stimulation: An Alternative Concept of Rehabilitation?

    Science.gov (United States)

    Giugno, Antonella; Gulì, Carlo; Basile, Luigi; Graziano, Francesca; Maugeri, Rosario; Visocchi, Massimiliano; Iacopino, Domenico Gerardo

    2017-01-01

    Chronic low back and leg pain is a disabling condition, affecting, in most cases, older patients with congenital or acquired spinal stenosis or patients with failed back surgery syndrome. Spinal cord stimulation has been introduced as an effective therapeutic option for those patients who have previously been operated without significant clinical benefits, or for all those patients who are ineligible for traditional surgery. We report our experience with ten patients treated with spinal cord stimulation plus medication and physical therapy between November 2014 and September 2015. Inclusion criteria were: previous surgical treatments for lumbar stenosis and metameric instability and persistent or ingravescent disabling low back and leg pain, with a mean duration of symptoms of at least 18 months. A visual analog scale (VAS) was employed for back and leg pain, and the Oswestry Disability Index (ODI) score was determined, and findings were analyzed after 6 months. No intra- or postoperative complication was recorded. The mean VAS score for back pain decreased from 7.5 to 2.9, while leg VAS decreased from 8.2 to 3.0. Analysis of ODI values showed evident improvement in daily life activities, ranging from a median value of 75.7% to 32.7 % after the stimulation. Spinal cord stimulation has a recognized impact on the pain and on the quality of life of patients with failed back surgery syndrome.

  15. The visual analogue WOMAC 3.0 scale--internal validity and responsiveness of the VAS version.

    Science.gov (United States)

    Kersten, Paula; White, Peter J; Tennant, Alan

    2010-04-30

    Many people suffer with Osteoarthritis (OA) and subsequent morbidity. Therefore, measuring outcome associated with OA is important. The Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) has been a widely used patient reported outcome in OA. However, there is relatively little evidence to support the use of the Visual Analogue Scale (VAS) version of the scale. We aimed to explore the internal validity and responsiveness of this VAS version of the WOMAC. Patients with chronic hip or knee pain of mechanical origin, waiting for a hip or knee joint replacement completed the WOMAC as part of a study to investigate the effects of acupuncture and placebo controls. Validity was tested using factor analysis and Rasch analysis, and responsiveness using standardised response means. Two hundred and twenty one patients (mean age 66.8, SD 8.29, 58% female) were recruited. Factor and Rasch analysis confirmed unidimensional Pain and Physical Functioning scales, capable of transformation to interval scaling and invariant over time. Some Differential Item Functioning (DIF) was observed, but this cancelled out at the test level. The Stiffness scale fitted the Rasch model but adjustments for DIF could not be made due to the shortness of the scale. Using the interval transformed data, Standardised Response Means were smaller than when using the raw, ordinal data. The WOMAC Pain and Physical Functioning subscales satisfied unidimensionality and ordinal scaling tests, and the ability to transform to an interval scale. Some Differential Item Functioning was observed, but this cancelled out at the test level and, by doing so, at the same time removed the disturbance of unidimensionality. The scaling characteristics of sets of items which use VAS require further analysis, as it would appear that they can lead to spurious levels of responsiveness and scale compression because they exaggerate the distortion of the ordinal scale. UKCRN study ID: 4881 ISRCTN78434638.

  16. COMPARISON OF EFFECTIVENESS OF NO-SCALPEL VASECTOMY WITH FASCIAL INTERPOSITION OF THE STUMPS OF VAS WITH NON-INTERPOSITION

    Directory of Open Access Journals (Sweden)

    Ajay Kumar

    2017-04-01

    Full Text Available BACKGROUND In contrast to female sterilisation in India, a very less percentage of the couples opt for male sterilisation. This is in spite of male sterilisation being a shorter, simpler procedure fraught with lesser complications, having a shorter recovery time and has less failure rate. The barriers to adoption of male sterilisation in India are profound with reasons ranging from unfounded fears among males characterising vasectomy with physical weakness, loss of virility, manhood and inability to enjoy intercourse. The aim of the study is to compare the effectiveness of No-scalpel vasectomy (NSV with fascial interposition of the stumps of vas with non-interposition MATERIALS AND METHODS The study was conducted in the family planning unit of the Department of O & G, Govt. Medical College, Kottayam. The period of study was one year from November 2015 to October 2016. The number of vasectomies during this period was 46. Acceptors posted for vasectomy were divided into 2 groups on a one-to-one basis. Hence, 22 were without fascial interposition and 24 with fascial interposition of the stumps of vas. After the vas is excised to 1 cm, the ligature of the testicular end is cut. The cut ends are passed into the scrotum. The uncut ligature of the prostatic end is pulled out through the wound. With the dissecting forceps, the fascial sheath of the vas deferens is grasped. The fascial membrane is tied below the tie of the prostatic end and then the stump of the prostatic end is slipped back into the scrotum. Hence, the stump of the testicular end is inside the fascial sheath, while the prostatic end is outside. During followup, satisfaction with the procedure was measured on the following domains - pain involved, time required to return to work after the procedure, problems in sexual life, by a questionnaire. A semen analysis was also done after 3 months. RESULTS No significance in the acceptor’s satisfaction between the two groups in terms of pain

  17. Vibroacoustic sound therapy: case studies with children with profound and multiple learning difficulties and the elderly in long-term residential care.

    Science.gov (United States)

    Ellis, Phil

    2004-01-01

    This paper describes the development of Vibroacoustic Sound Therapy, an approach which is being developed for use in special schools for children with profound and multiple learning difficulties, and in long-term care homes for the elderly and the elderly mentally infirm. Using non-invasive techniques and music/sound technology, children and the elderly are being empowered and enabled to (re)discover self expression and communication skills. Two case studies drawn from the world of the young disabled, and from the elderly, illustrate the potential for improving quality of life and well-being in these institutional settings.

  18. Effect of on-site Coulomb interaction on electronic and transport properties of 100% spin polarized CoMnVAs

    Energy Technology Data Exchange (ETDEWEB)

    Bhat, Tahir Mohiuddin; Gupta, Dinesh C., E-mail: sosfizix@gmail.com

    2017-08-01

    Highlights: • 100% spin-polarized material important for the application in spintronics. • Ferromagnetic nature. • Ductile in nature for mechanical applications. • Semiconducting behavior with a band gap of 0.55 eV in minority spin channel. • Possibly efficient thermoelectric material. - Abstract: The structural, electronic, magnetic and transport properties of a new quaternary Heusler alloy CoMnVAs have been investigated by employing generalized gradient approximation (GGA), modified Becke-Johnson (mBJ) and GGA with Hubbard U correction (GGA + U). The alloy is energetically more stable in ferromagnetic Y{sub 1} type structure. Elastic parameters reveal high anisotropy and ductile nature of the material. CoMnVAs shows half-metallic ferromagnet character with 100% spin polarization at Fermi level with band gap of 0.55 eV in the minority spin state. The alloy also possesses high electrical conductivity and Seebeck coefficients with 15 μVK{sup −1} at room temperature, achieving a figure of merit of 0.65 at high temperatures. The high degree of ductility, 100% spin polarization and large Seebeck coefficient, makes it an attractive candidate to be used in spin voltage generators and thermoelectric materials.

  19. R + C Factors and Sacro Occipital Technique Orthopedic Blocking: a pilot study using pre and post VAS assessment.

    Science.gov (United States)

    Blum, Charles L

    2015-06-01

    The concept of a systematic or predictive relationship between distant vertebral levels distinct from accumulative functional compensatory mechanisms, such as in scoliosis, has been perpetuated within chiropractic technique systems based on clinical observation and experience. This study seeks to investigate this relationship between the cervical and lumbar vertebrae. Patients (experimental group n=26 and control group n=12) were selected from the patient base of one office, and were limited to patients that had sensitivity at specific cervical reflex points. Using a pre and post outcome measurement and sacro occipital technique R + C protocols, the related lumbar vertebra was adjusted in the direction indicated by the cervical vertebral sensitivity. Statistical analysis revealed there was a statistically significant difference between pre- and post-VAS measurements and found that the notable difference in mean change in VAS scores were statistically significantly different between the experimental and control groups (p < .001). The findings of this study suggest that further research into cervical and lumbar vertebra interrelationships, and the efficacy of orthopedic block treatment, may be warranted. Further studies are needed to confirm whether a causal relationship exists between lumbar manipulation and decreased cervical spine sensitivity.

  20. The nature of alarm communication in Constrictotermes cyphergaster (Blattodea: Termitoidea: Termitidae): the integration of chemical and vibroacoustic signals.

    Science.gov (United States)

    Cristaldo, Paulo F; Jandák, Vojtĕch; Kutalová, Kateřina; Rodrigues, Vinícius B; Brothánek, Marek; Jiříček, Ondřej; DeSouza, Og; Šobotník, Jan

    2015-11-04

    Alarm signalling is of paramount importance to communication in all social insects. In termites, vibroacoustic and chemical alarm signalling are bound to operate synergistically but have never been studied simultaneously in a single species. Here, we inspected the functional significance of both communication channels in Constrictotermes cyphergaster (Termitidae: Nasutitermitinae), confirming the hypothesis that these are not exclusive, but rather complementary processes. In natural situations, the alarm predominantly attracts soldiers, which actively search for the source of a disturbance. Laboratory testing revealed that the frontal gland of soldiers produces a rich mixture of terpenoid compounds including an alarm pheromone. Extensive testing led to identification of the alarm pheromone being composed of abundant monoterpene hydrocarbons (1S)-α-pinene and myrcene, along with a minor component, (E)-β-ocimene. The vibratory alarm signalling consists of vibratory movements evidenced as bursts; a series of beats produced predominantly by soldiers. Exposing termite groups to various mixtures containing the alarm pheromone (crushed soldier heads, frontal gland extracts, mixture of all monoterpenes, and the alarm pheromone mixture made of standards) resulted in significantly higher activity in the tested groups and also increased intensity of the vibratory alarm communication, with the responses clearly dose-dependent. Lower doses of the pheromone provoked higher numbers of vibratory signals compared to higher doses. Higher doses induced long-term running of all termites without stops necessary to perform vibratory behaviour. Surprisingly, even crushed worker heads led to low (but significant) increases in the alarm responses, suggesting that other unknown compound in the worker's head is perceived and answered by termites. Our results demonstrate the existence of different alarm levels in termites, with lower levels being communicated through vibratory signals, and

  1. The nature of alarm communication in Constrictotermes cyphergaster (Blattodea: Termitoidea: Termitidae: the integration of chemical and vibroacoustic signals

    Directory of Open Access Journals (Sweden)

    Paulo F. Cristaldo

    2015-12-01

    Full Text Available Alarm signalling is of paramount importance to communication in all social insects. In termites, vibroacoustic and chemical alarm signalling are bound to operate synergistically but have never been studied simultaneously in a single species. Here, we inspected the functional significance of both communication channels in Constrictotermes cyphergaster (Termitidae: Nasutitermitinae, confirming the hypothesis that these are not exclusive, but rather complementary processes. In natural situations, the alarm predominantly attracts soldiers, which actively search for the source of a disturbance. Laboratory testing revealed that the frontal gland of soldiers produces a rich mixture of terpenoid compounds including an alarm pheromone. Extensive testing led to identification of the alarm pheromone being composed of abundant monoterpene hydrocarbons (1S-α-pinene and myrcene, along with a minor component, (E-β-ocimene. The vibratory alarm signalling consists of vibratory movements evidenced as bursts; a series of beats produced predominantly by soldiers. Exposing termite groups to various mixtures containing the alarm pheromone (crushed soldier heads, frontal gland extracts, mixture of all monoterpenes, and the alarm pheromone mixture made of standards resulted in significantly higher activity in the tested groups and also increased intensity of the vibratory alarm communication, with the responses clearly dose-dependent. Lower doses of the pheromone provoked higher numbers of vibratory signals compared to higher doses. Higher doses induced long-term running of all termites without stops necessary to perform vibratory behaviour. Surprisingly, even crushed worker heads led to low (but significant increases in the alarm responses, suggesting that other unknown compound in the worker's head is perceived and answered by termites. Our results demonstrate the existence of different alarm levels in termites, with lower levels being communicated through

  2. SmEdA vibro-acoustic modelling in the mid-frequency range including the effect of dissipative treatments

    Science.gov (United States)

    Hwang, H. D.; Maxit, L.; Ege, K.; Gerges, Y.; Guyader, J.-L.

    2017-04-01

    Vibro-acoustic simulation in the mid-frequency range is of interest for automotive and truck constructors. The dissipative treatments used for noise and vibration control such as viscoelastic patches and acoustic absorbing materials must be taken into account in the problem. The Statistical modal Energy distribution Analysis (SmEdA) model consists in extending Statistical Energy Analysis (SEA) to the mid-frequency range by establishing power balance equations between the modes of the different subsystems. The modal basis of uncoupled-subsystems that can be estimated by the finite element method in the mid-frequency range is used as input data. SmEdA was originally developed by considering constant modal damping factors for each subsystem. However, this means that it cannot describe the local distribution of dissipative materials. To overcome this issue, a methodology is proposed here to take into account the effect of these materials. This methodology is based on the finite element models of the subsystems that include well-known homogenized material models of dissipative treatments. The Galerkin method with subsystem normal modes is used to estimate the modal damping loss factors. Cross-modal coupling terms which appear in the formulation due to the dissipative materials are assumed to be negligible. An approximation of the energy sharing between the subsystems damped by dissipative materials is then described by SmEdA. The different steps of the method are validated experimentally by applying it to a laboratory test case composed of a plate-cavity system with different configurations of dissipative treatments. The comparison between the experimental and the simulation results shows good agreement in the mid-frequency range.

  3. The nature of alarm communication in Constrictotermes cyphergaster (Blattodea: Termitoidea: Termitidae): the integration of chemical and vibroacoustic signals

    Science.gov (United States)

    Cristaldo, Paulo F.; Jandák, Vojtĕch; Kutalová, Kateřina; Rodrigues, Vinícius B.; Brothánek, Marek; Jiříček, Ondřej; DeSouza, Og; Šobotník, Jan

    2015-01-01

    ABSTRACT Alarm signalling is of paramount importance to communication in all social insects. In termites, vibroacoustic and chemical alarm signalling are bound to operate synergistically but have never been studied simultaneously in a single species. Here, we inspected the functional significance of both communication channels in Constrictotermes cyphergaster (Termitidae: Nasutitermitinae), confirming the hypothesis that these are not exclusive, but rather complementary processes. In natural situations, the alarm predominantly attracts soldiers, which actively search for the source of a disturbance. Laboratory testing revealed that the frontal gland of soldiers produces a rich mixture of terpenoid compounds including an alarm pheromone. Extensive testing led to identification of the alarm pheromone being composed of abundant monoterpene hydrocarbons (1S)-α-pinene and myrcene, along with a minor component, (E)-β-ocimene. The vibratory alarm signalling consists of vibratory movements evidenced as bursts; a series of beats produced predominantly by soldiers. Exposing termite groups to various mixtures containing the alarm pheromone (crushed soldier heads, frontal gland extracts, mixture of all monoterpenes, and the alarm pheromone mixture made of standards) resulted in significantly higher activity in the tested groups and also increased intensity of the vibratory alarm communication, with the responses clearly dose-dependent. Lower doses of the pheromone provoked higher numbers of vibratory signals compared to higher doses. Higher doses induced long-term running of all termites without stops necessary to perform vibratory behaviour. Surprisingly, even crushed worker heads led to low (but significant) increases in the alarm responses, suggesting that other unknown compound in the worker's head is perceived and answered by termites. Our results demonstrate the existence of different alarm levels in termites, with lower levels being communicated through vibratory

  4. Vibroacoustics of the piano soundboard: (Non)linearity and modal properties in the low- and mid-frequency ranges

    Science.gov (United States)

    Ege, Kerem; Boutillon, Xavier; Rébillat, Marc

    2013-03-01

    The piano soundboard transforms the string vibration into sound and therefore, its vibrations are of primary importance for the sound characteristics of the instrument. An original vibro-acoustical method is presented to isolate the soundboard nonlinearity from that of the exciting device (here: a loudspeaker) and to measure it. The nonlinear part of the soundboard response to an external excitation is quantitatively estimated for the first time, at ≈-40 dB below the linear part at the ff nuance. Given this essentially linear response, a modal identification is performed up to 3 kHz by means of a novel high resolution modal analysis technique [K. Ege, X. Boutillon, B. David, High-resolution modal analysis, Journal of Sound and Vibration 325 (4-5) (2009) 852-869]. Modal dampings (which, so far, were unknown for the piano in this frequency range) are determined in the mid-frequency domain where FFT-based methods fail to evaluate them with an acceptable precision. They turn out to be close to those imposed by wood. A finite-element modelling of the soundboard is also presented. The low-order modal shapes and the comparison between the corresponding experimental and numerical modal frequencies suggest that the boundary conditions can be considered as blocked, except at very low frequencies. The frequency-dependency of the estimated modal densities and the observation of modal shapes reveal two well-separated regimes. Below ≈1 kHz, the soundboard vibrates more or less like a homogeneous plate. Above that limit, the structural waves are confined by ribs, as already noticed by several authors, and localised in restricted areas (one or a few inter-rib spaces), presumably due to a slightly irregular spacing of the ribs across the soundboard.

  5. Technical Note: Treatment of Sacroiliac Joint Pain with Peripheral Nerve Stimulation.

    Science.gov (United States)

    Guentchev, Marin; Preuss, Christian; Rink, Rainer; Peter, Levente; Wocker, Ernst-Ludwig; Tuettenberg, Jochen

    2015-07-01

    Sacroiliac joint (SIJ) pain affects older adults with a prevalence of up to 20% among patients with chronic low back pain. While pain medication, joint blocks and denervation procedures achieve pain relief in most patients, some cases fail to improve. Our goal was to determine the effectiveness of SIJ peripheral nerve stimulation in patients with severe conservative therapy-refractory SIJ pain. Here we present 12 patients with severe conservative therapy-refractory pain receiving an SIJ peripheral nerve stimulation. Patient satisfaction, pain, and quality of life were evaluated by means of the International Patient Satisfaction Index (IPSI), visual analog scale (VAS), and Oswestry Disability Index 2.0 (ODI) using standard questionnaires. For stimulation we placed an eight-pole peripheral nerve electrode parallel to the SIJ. Two weeks postoperatively, our patients reported an average ODI reduction from 57% to 32% and VAS from 9 to 2.1. IPSI was 1.1. After six months, the therapy was rated as effective in seven out of eight patients reporting at that period. The average ODI was low at 34% (p = 0.0006), while the VAS index rose to 3.8 (p VAS 1.7 (p < 0.0001), and IPSI 1.3. We conclude that SIJ stimulation is a promising therapeutic strategy in the treatment of intractable SIJ pain. Further studies are required to determine the precise target group and long-term effect of this novel treatment method. © 2014 International Neuromodulation Society.

  6. Comparing responsiveness of the EQ-5D-5L, EQ-5D-3L and EQ VAS in stroke patients.

    Science.gov (United States)

    Golicki, Dominik; Niewada, Maciej; Karlińska, Anna; Buczek, Julia; Kobayashi, Adam; Janssen, M F; Pickard, A Simon

    2015-06-01

    To date, evidence to support the construct validity of the EQ-5D-5L has primarily focused on cross-sectional data. The aims of this study were to examine the responsiveness of EQ-5D-5L in patients with stroke and to compare it with responsiveness of EQ-5D-3L and visual analogue scale (EQ VAS). We performed an observational longitudinal cohort study of patients with stroke. At 1 week and 4 months post-stroke, patients were assessed with modified Rankin Scale (mRS) and Barthel Index (BI) and were administered the EQ-5D-5L and EQ-5D-3L, including the EQ VAS. The EQ-5D-5L index scores were derived using the crosswalk methodology developed by the EuroQol Group. We classified patients according to two external criteria, based on mRS or BI, into 3 categories: 'improvement,' 'stable' or 'deterioration'. We assessed the responsiveness of each measure in each patient subgroup using: effect size (ES), standardized response mean (SRM), F-statistic, relative efficiency and area under the receiver operating characteristic curve. A total of 112 patients (52% females; mean age 70.6 years; 93% ischemic stroke) completed all the instruments at both occasions. In subjects with clinical improvement, EQ-5D-5L was consistently responsive, showing moderate ES (0.51-0.71) and moderate to large SRM (0.69-0.86). In general, EQ-5D-3L index appeared to be more responsive (ES 0.63-0.82; SRM 0.77-1.06) and EQ VAS less responsive (ES 0.51-0.65; SRM 0.59-0.69) than EQ-5D-5L index. The EQ-5D-5L index, based on the crosswalk value set, seems to be appropriately responsive in patients with stroke, 4 months after disease onset. As far as EQ-5D-5L index is scored according to crosswalk approach, the EQ-5D-3L index appears to be more responsive in stroke population.

  7. Seasonal reproductive activity and innervation of vas deferens and accessory male genital glands in the water buffalo (Bubalus bubalis

    Directory of Open Access Journals (Sweden)

    G. Paino

    2010-02-01

    Full Text Available Autonomic nerves supplying mammalian male internal genital organs have an important role in the regulation of reproductive function. To find out the relationships between the neurochemical content of these nerves and the reproductive activity, we performed an immunohistochemical study in a species, the water buffalo, exhibiting a seasonal sexual behaviour. The distribution of noradrenergic and peptide-containing nerves was evaluated during the mating (autumn-winter and non-mating (spring-summer periods. During the mating period, a dense noradrenergic innervation was observed to supply the vas deferens as well as the accessory genital glands. Peptide-containing nerves were also observed but with a lower density. During the non-mating period noradrenergic nerves dramatically reduced. These results suggest that there is a neuro-endocrine interaction between androgen hormones and the autonomic nerve supply in the regulation of male water buffalo reproductive functions.

  8. growth stimulant

    African Journals Online (AJOL)

    Effects of timing and duration of supplementation of LIVFIT VET ® (growth stimulant) as substitute for fish meal on the growth performance, haematology and clinical enzymes concentration of growing pigs.

  9. Population-Based Preference Weights for the EQ-5D Health States Using the Visual Analogue Scale (VAS) in Iran

    Science.gov (United States)

    Goudarzi, Reza; Zeraati, Hojjat; Akbari Sari, Ali; Rashidian, Arash; Mohammad, Kazem

    2016-01-01

    Background Health-related quality of life (HRQoL) is used as a measure to valuate healthcare interventions and guide policy making. The EuroQol EQ-5D is a widely used generic preference-based instrument to measure Health-related quality of life. Objectives The objective of this study was to develop a value set of the EQ-5D health states for an Iranian population. Patients and Methods This study is a cross-sectional study of Iranian populations. Our sample from Iranian populations consists out of 869 participants, who were selected for this study using a stratified probability sampling method. The sample was taken from individuals living in the city of Tehran and was stratified by age and gender from July to November 2013. Respondents valued 13 health states using the visual analogue scale (VAS) of the EQ-5D. Several fixed effects regression models were tested to predict the full set of health states. We selected the final model based on the logical consistency of the estimates, the sign and magnitude of the regression coefficients, goodness of fit, and parsimony. We also compared predicted values with a value set from similar studies in the UK and other countries. Results Our results show that the HRQoL does not vary among socioeconomic groups. Models at the individual level resulted in an additive model with all coefficients being statistically significant, R2 = 0.55, a value of 0.75 for the best health state (11112), and a value of -0.074 for the worst health state (33333). The value set obtained for the study sample remarkably differs from those elicited in developed countries. Conclusions This study is the first estimate for the EQ-5D value set based on the VAS in Iran. Given the importance of locally adapted value set the use of this value set can be recommended for future studies in Iran and In the EMRO regions. PMID:27186384

  10. Cross-sectional study of alteration of phantom limb pain with visceral stimulation in military personnel with amputation.

    Science.gov (United States)

    Rafferty, Michael; Bennett Britton, Thomas M; Drew, Benjamin T; Phillip, Rhodri D

    2015-01-01

    While phantom limb pain is a well-recognized phenomenon, clinical experience has suggested that the augmentation of phantom limb pain with visceral stimulation is an issue for many military personnel with amputation (visceral stimulation being the sensation of the bowel or bladder either filling or evacuating). However, the prevalence of this phenomenon is not known. The aim of this study was to investigate the prevalence of the alteration in phantom limb pain and the effect that visceral stimulation has on phantom limb pain intensity. A cross-sectional study of 75 military personnel who have lost one or both lower limbs completed a questionnaire to assess the prevalence of the alteration of phantom limb pain with visceral stimulation. Included in the questionnaire was a pain visual analog scale (VAS) graded from 0 to 10. Patients recorded the presence and intensity of phantom limb pain. They also recorded whether and how this pain altered with a need to micturate or micturition, and/or a need to defecate or defecation, again using a pain VAS. Time since amputation, level of amputation, and medications were also recorded. Patients reported a phantom limb pain prevalence of 85% with a mean VAS of 3.6. In all, 56% of patients reported a change in the severity of phantom limb pain with visceral stimuli. The mean increase in VAS for visceral stimulation was 2.5 +/- 1.6 for bladder stimulation and 2.9 +/- 2.0 for bowel stimulation. Of the patients questioned, 65% reported an improvement in symptoms over time. VAS scores were highest in the subgroup less than 6 mo postamputation. An increase in phantom limb pain with visceral stimulation is a common problem for military personnel with amputation.

  11. Optimal stimulation settings for CMAP scan registrations

    Directory of Open Access Journals (Sweden)

    Maathuis Ellen M

    2012-06-01

    Full Text Available Abstract Background The CMAP (Compound Muscle Action Potential scan is a non-invasive electrodiagnostic tool, which provides a quick and visual assessment of motor unit potentials as electrophysiological components that together constitute the CMAP. The CMAP scan records the electrical activity of the muscle (CMAP in response to transcutaneous stimulation of the motor nerve with gradual changes in stimulus intensity. Large MUs, including those that result from collateral reinnervation, appear in the CMAP scan as so-called steps, i.e., clearly visible jumps in CMAP amplitude. The CMAP scan also provides information on nerve excitability. This study aims to evaluate the influence of the stimulation protocol used on the CMAP scan and its quantification. Methods The stimulus frequency (1, 2 and 3 Hz, duration (0.05, 0.1 and 0.3 ms, or number (300, 500 and 1000 stimuli in CMAP scans of 23 subjects was systematically varied while the other two parameters were kept constant. Pain was measured by means of a visual analogue scale (VAS. Non-parametric paired tests were used to assess significant differences in excitability and step variables and VAS scores between the different stimulus parameter settings. Results We found no effect of stimulus frequency on CMAP scan variables or VAS scores. Stimulus duration affected excitability variables significantly, with higher stimulus intensity values for shorter stimulus durations. Step variables showed a clear trend towards increasing values with decreasing stimulus number. Conclusions A protocol delivering 500 stimuli at a frequency of 2 Hz with a 0.1 ms pulse duration optimized CMAP scan quantification with a minimum of subject discomfort, artefact and duration of the recording. CMAP scan variables were influenced by stimulus duration and number; hence, these need to be standardized in future studies.

  12. The Effects of Stretching with Lumbar Traction on VAS and Oswestry Scales of Patients with Lumbar 4-5 Herniated Intervertebral Disc.

    Science.gov (United States)

    Yang, Hae-Sun; Yoo, Won-Gyu

    2014-07-01

    [Purpose] This study investigated the effect of stretching with lumbar traction on VAS and Oswestry scale scores of lumbar 4-5 herniated intervertebral disc (HIVD) patients. [Subjects] We recruited 20 lumbar 4-5 HIVD patients. [Methods] We performed stretching with lumbar traction for lumbar 4-5 HIVD patients during 4 weeks. The VAS and Oswestry scales were measured before and 4 weeks after the intervention. [Results] The results showed a significant decrease in VAS scale scores for stretching with lumbar traction in lumbar 4-5 HIVD patients, from 18±1.29 to 2.1±1.35. The Oswestry scale scores also decreased significantly, from 20.35±2.01 to 3.5±2.84, after stretching with lumbar traction. [Conclusion] Thus, we suggest stretching with lumbar traction for lumbar 4-5 HIVD patients.

  13. Effects of the combined PNF and deep breathing exercises on the ROM and the VAS score of a frozen shoulder patient: Single case study.

    Science.gov (United States)

    Lee, Byung-Ki

    2015-10-01

    This study was conducted to examine the influence of combined exercise using proprioceptive neuromuscular facilitation (PNF) and deep breathing exercise on range of motion (ROM) and visual analog scale (VAS) score in acute frozen shoulder patient. The subject of this study was woman complained disabilities in daily routine due as a frozen left shoulder. The exercise program was composed of 11 sessions and continued four weeks. The program was composed of PNF and deep breathing exercise, and the subject was compared by passive ROM (shoulder flexion, abduction, and internal and external rotation) test and VAS score in shoulder movement before and after the exercise. The results showed that patient who practiced this program, the ROM of the shoulder joint increased and the VAS score decreased. Thus, this program was shown to be effective in suppressing pain and increasing the ROM of the shoulder joint in acute frozen shoulder patient.

  14. Computation of leaky guided waves dispersion spectrum using vibroacoustic analyses and the Matrix Pencil Method: a validation study for immersed rectangular waveguides.

    Science.gov (United States)

    Mazzotti, M; Bartoli, I; Castellazzi, G; Marzani, A

    2014-09-01

    The paper aims at validating a recently proposed Semi Analytical Finite Element (SAFE) formulation coupled with a 2.5D Boundary Element Method (2.5D BEM) for the extraction of dispersion data in immersed waveguides of generic cross-section. To this end, three-dimensional vibroacoustic analyses are carried out on two waveguides of square and rectangular cross-section immersed in water using the commercial Finite Element software Abaqus/Explicit. Real wavenumber and attenuation dispersive data are extracted by means of a modified Matrix Pencil Method. It is demonstrated that the results obtained using the two techniques are in very good agreement. Copyright © 2014 Elsevier B.V. All rights reserved.

  15. Would turbine uprating be allowable with respect to cavitation? An example of vibroacoustic diagnosis; Turbinenleistungserhoehung - Waere sie zulaessig im Hinblick auf die Kavitation? Beispiel einer vibroakustischen Diagnose

    Energy Technology Data Exchange (ETDEWEB)

    Bajic, B.

    1999-04-01

    Velocity field disturbances at the inflow to the runner of a turbine caused by the stay and guide vanes alter the vibroacoustic cavitation signature. This telltale amplitude modulation can be a means to identify the incipient, weak, or moderate cavitation related to each vane/runner blade pair. An application of this method is presented identifying the turbine parts responsible for the increase of cavitation predicted when uprating a 60 MW Kaplan turbine. (orig.) [German] Stoerungen im Geschwindigkeitsfeld am Einlauf zu einem Turbinenlaufrad, hervorgerufen durch die Stuetz- und Leitschaufeln, veraendern die vibroakustischen Kavitationsanzeichen. Diese aussagekraeftige Amplitudenmodulation kann herangezogen werden, um die beginnende, schwache oder mittelmaessige Kavitation fuer jedes Paar aus Leitschaufel (Stuetz- und Leitschaufel) und Laufradschaufel zu bestimmen. Hier wird ein Anwendungsbeispiel dieser Methode vorgestellt, wobei diejenigen Turbinenteile identifiziert werden, die fuer die vorhergesagte Zunahme der Kavitation im Falle der Nennleistungserhoehung einer 60 MW Kaplan-Turbine verantwortlich sind. (orig.)

  16. Long-Term Reduction of Sacroiliac Joint Pain With Peripheral Nerve Stimulation.

    Science.gov (United States)

    Guentchev, Marin; Preuss, Christian; Rink, Rainer; Peter, Levente; Sailer, Martin H M; Tuettenberg, Jochen

    2017-10-01

    We recently demonstrated that 86% of the patients treated with peripheral nerve stimulation (PNS) for therapy-refractory sacroiliac joint (SIJ) pain were satisfied with the result after 1 year of treatment. To investigate the long-term (up to 4 years) response rate of this novel treatment. Sixteen consecutive patients with therapy-refractory SIJ pain were treated with PNS and followed for 4 years in 3 patients, 3 years in 6 patients, and 2 years in 1 patient. Quality of life, pain, and patient satisfaction were assessed using the Oswestry Disability Index 2.0, Visual Analog Scale (VAS), and International Patient Satisfaction Index. Patients reported a pain reduction from 8.8 to 1.6 (VAS) at 1 year ( P VAS of 2.0 ( P < .005). At 4 years, 2 of 3 patients were satisfied with the treatment results. We have shown for the first time that PNS is a successful long-term therapy for SIJ pain.

  17. Brain Stimulation Therapies

    Science.gov (United States)

    ... Magnetic Seizure Therapy Deep Brain Stimulation Additional Resources Brain Stimulation Therapies Overview Brain stimulation therapies can play ... for a shorter recovery time than ECT Deep Brain Stimulation Deep brain stimulation (DBS) was first developed ...

  18. [Congenital bilateral absence of vas deferens: From diagnosis to assisted reproductive techniques - the experience of three centers].

    Science.gov (United States)

    Beauvillard, D; Perrin, A; Drapier, H; Ravel, C; Fréour, T; Férec, C; De Braekeleer, M; Amice, V

    2015-05-01

    To review the management with assisted reproductive technologies (ART) of men with congenital bilateral absence of vas deferens (CBAVD), associated with cystic fibrosis or not, after surgical retrieval [epididymal aspiration (MESA) or testicular biopsy (TESE)]. Multicenter retrospective study made of 2 groups: CBAVD and cystic fibrosis (CF) or CBAVD only (CF-RD). Two centers performed MESA (Brest and Nantes) and one TESE (Rennes). Sperm numeration, motility, vitality, morphology and nuclear maturity were measured in both centers performing MESA. Fertilization rate (TF) and cumulated progressive pregnancy rate by retrieved oocyte (TGC) were compared between centers following ART. Ninety patients underwent surgical retrieval between January 1996 and March 2013, 30 in the CF group and 60 in the CF-RD group. Semen parameters were comparable between groups and centers. Fifty-eight (22 in the CF group and 36 in the CF-RD group) patients received ART between April 1996 and October 2014. TF was 50% and 52% and TGC 26% and 32% in the CF group and CF-RD groups, respectively. The results did not differ between groups but TGC was higher in Rennes than in the other two centers. Both semen parameters and ART results are comparable and similar to those reported in the literature. As shown by the results obtained in Rennes, TESE seems to be more effective. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

  19. A global perspective on the use, sales, exposure pathways, occurrence, fate and effects of veterinary antibiotics (VAs) in the environment

    Science.gov (United States)

    Sarmah, Ajit K.; Meyer, Michael T.; Boxall, Alistair B.A.

    2006-01-01

    Veterinary antibiotics (VAs) are widely used in many countries worldwide to treat disease and protect the health of animals. They are also incorporated into animal feed to improve growth rate and feed efficiency. As antibiotics are poorly adsorbed in the gut of the animals, the majority is excreted unchanged in faeces and urine. Given that land application of animal waste as a supplement to fertilizer is often a common practice in many countries, there is a growing international concern about the potential impact of antibiotic residues on the environment. Frequent use of antibiotics has also raised concerns about increased antibiotic resistance of microorganisms. We have attempted in this paper to summarize the latest information available in the literature on the use, sales, exposure pathways, environmental occurrence, fate and effects of veterinary antibiotics in animal agriculture. The review has focused on four important groups of antibiotics (tylosin, tetracycline, sulfonamides and, to a lesser extent, bacitracin) giving a background on their chemical nature, fate processes, occurrence, and effects on plants, soil organisms and bacterial community. Recognising the importance and the growing debate, the issue of antibiotic resistance due to the frequent use of antibiotics in food-producing animals is also briefly covered. The final section highlights some unresolved questions and presents a way forward on issues requiring urgent attention.

  20. Retrieving Vegetation Water Content from MODIS, High Resolution and Ground Data in the SMOS VAS Cal/Val Site

    Science.gov (United States)

    Camacho, F.; Cernicharo, J.; Martinez, B.; Lopez-Baeza, E.

    2010-12-01

    Ground measurements are required to calibrate/validate remote sensing products. This work describes a method to derive vegetation water content (VWC) maps at medium resolution from ground data, applied to the VAS (Valencia Anchor Station) cal/val area for SMOS soil moisture products. The method is based on a transfer function that establishes an empirical relationship between in-situ data and reflectance values retrieved from high resolution (CHRIS/PROBA, TM/LANDSAT) and medium resolution (MODIS/TERRA+AQUA) imagery. The up-scaling process is developed in two steps: (1) by using in-situ values with CHRIS and TM data to derive high resolution ground based maps over small regions, and (2) using the high resolution maps with MODIS data to produce the medium resolution ground based maps over the whole region. The convex hull technique has been proposed to assess the transfer function interpolation quality. Results obtained by applying the selected band combination of bands show cross validation errors (RC=0.221 kg/m2 and RC=0.051 kg/m2 for high-resolution and RC=0.386 kg/m2 for medium resolution) lower than traditional spectral indices ones, good correlations with observed data and a high interpolation capacity (70% and 95%). VWC mean values at medium resolution range between 0.04 kg/m2, for non-irrigated areas, and 0.7 kg/m2, for irrigated crops.

  1. Minimal clinically important differences (MCID) and patient acceptable symptomatic state (PASS) for visual analog scales (VAS) measuring pain in patients treated for rotator cuff disease.

    Science.gov (United States)

    Tashjian, Robert Z; Deloach, Julia; Porucznik, Christina A; Powell, Amy P

    2009-01-01

    The MCID is the smallest difference in an outcome score which a patient perceives as beneficial. The PASS is the score below which patients consider themselves well. The purpose of this study was to determine the MCID and PASS for a visual analog scale (VAS) measuring pain in patients treated for rotator cuff disease. 81 patients with rotator cuff disease were evaluated after 6 weeks of non-operative treatment with a VAS measuring pain and two transition questions utilized in determining the MCID and PASS. The MCID and PASS were estimated to be 1.4 cm (P = .0255) and 3 cm (95% CI - 22.69, 37.31) on a 10 cm VAS measuring pain, respectively. Age (P = .0492) and hand-dominance (P = .0325) affected the MCID while age (P = .0376) and duration of follow-up (P = .0131) affected the PASS. The MCID and PASS estimates provide the basis to determine if statistically significant changes in VAS pain scores after treatment are clinically important and if the treatment allowed patients to achieve a satisfactory state. Level 3; Nonconsecutive series of patients, diagnostic study.

  2. Vibro-acoustic methods for the determination of the technical state of a refrigeration piston compressor. A check-up for the compressor. Vibroakustische Verfahren zur Bestimmung des technischen Zustandes eines Kaeltekolbenverdichters. Ein Check-up fuer den Verdichter

    Energy Technology Data Exchange (ETDEWEB)

    Milowanow, V.I.; Lopatinskaja, E.S.

    1990-10-01

    Independent of the kind of refrigeration plant the actual service life is limited by the service life of the compressor. In case of refrigeration machinery with small-type refrigeration compressors for refrigerated transport systems a periodical check of the system before setting out is particularly important. A spectral analysis process is recommended for the diagnosis. But due to the particularities of the plants this is only suited for systems for vibroacoustic diagnosis. This technique is presented using charts and diagrams. (BWI).

  3. Improved Pain Relief With Burst Spinal Cord Stimulation for Two Weeks in Patients Using Tonic Stimulation: Results From a Small Clinical Study

    Science.gov (United States)

    Courtney, Peter; Espinet, Anthony; Mitchell, Bruce; Russo, Marc; Muir, Andrew; Verrills, Paul

    2015-01-01

    Objectives Conventional spinal cord stimulation (SCS) delivers a tonic waveform with consistent stream of pulses; burst delivers groups of pulses separated by short pulse‐free periods. The current study compared the short‐term safety and efficacy of burst with tonic stimulation in subjects already receiving SCS. Materials and Methods At 4 IRB‐approved sites, 22 subjects previously implanted with an SCS device for intractable, chronic pain gave informed consent and received burst stimulation for 14 days. Subjects reported average daily Visual Analog Scale (VAS) for overall, trunk, and limb pain using tonic stimulation and after 7 and 14 days of burst stimulation. Thoughts about pain were assessed using the Pain Catastrophizing Scale. Areas of paresthesia were assessed during tonic and burst stimulation using body maps. Assessment of patient satisfaction and preferred stimulation occurred after 14 days of burst. Results Average daily overall VAS reduced 46% from a mean of 53.5 (±20.2) mm during tonic SCS to 28.5 (±18.1) mm during burst (p VAS scores were also reduced by 33% and 51%, respectively. During burst, 16 subjects (73%) reported no paresthesia, 5 (23%) reported a reduction, and 1 (4%) reported increased paresthesia. After 14 days, 21 subjects (95%) reported being very satisfied or satisfied with burst. Burst was preferred by 20 subjects (91%), tonic by 1 (5%), and 1 (5%) reported no preference. Better pain relief was the most common reason cited for preference. Conclusions A majority of subjects reported improved pain relief using burst compared with tonic stimulation. Most subjects experienced less paresthesia during burst and preferred burst citing better pain relief. PMID:25879884

  4. Is aphallic vas deferens development in females related to the distance from organotin sources? A study with Stramonita haemastoma.

    Science.gov (United States)

    Toste, R; Pessoa, I A; Dore, M P; Parahyba, M A; Fernandez, M A

    2013-05-01

    Imposex, a syndrome characterized by the appearance of a penis and/or vas deferens in female gastropods due the presence of organotins in environment, is still observed in Brazilian gastropod populations, as in other countries, even after the tributyltin (TBT) ban. Nevertheless, the progressive controls on the use of organotins in antifouling systems at national and international levels and the consequent reduction of their environmental concentrations have led to changes in the characteristics of imposex development observed in Stramonita haemastoma. Populations of this species were analyzed on the coast of Rio de Janeiro (Brazil) between 2007 and 2008, and the developmental pathways associated with the syndrome were identified. Compared with previous works, it was noted that imposex expression was reduced in most of Guanabara Bay. Aphallic imposex development, on the other hand, showed a marked increase. The pathways of imposex development were also evaluated in a temporal data series from a fixed sampling station at Vermelha beach, and the incidence of aphallic imposex development was found to show a marked increase from 1998 onward. Furthermore, the observation of either the presence or absence of a penis in imposex-affected females may indicate that penis development is related to the contaminant exposure level and that the decreasing TBT concentrations in the local environment result in the predominance of an aphallic route of imposex development. These findings support the idea that imposex female aphally in this species could be a dose-dependent response, rather than a genetic anomaly. Copyright © 2013 Elsevier Inc. All rights reserved.

  5. [Multisensory stimulation].

    Science.gov (United States)

    Etchepareborda, M C; Abad-Mas, L; Pina, J

    2003-02-01

    Diagnosis in early care (EC) involves a global study that covers the child's development, their personal history, family and surroundings. The specific aims of an intervention programme in EC could be summed up in four areas: the prevention of deficits or difficulties, the detection of problems linked with a socio-family deficiency or shortages, the stimulation of development, and help and assistance for families. Multisensory stimulation (MSS) of small children is essential for their future existence. The presentation of stimuli must follow a strict schedule; indeed, this observation is so important that if the critical moment for incorporating a stimulus is missed, providing the stimulus at another time will not have the same effect. Intellectual development during early childhood was taken into account when defining the fundamental aims of a therapeutic intervention programme in EC. To develop suitable therapy according to these concepts, an EMS (Snoezelen) room with certain special characteristics is required. This room must allow the stimuli offered in each moment and under each sensory modality to be controlled. Applying intervention programmes in a proper, specific and timely manner will enable us to accompany each child, as far as is possible in each case, in the development of his or her abilities and capabilities.

  6. Vibroacoustic Skin Diagnostics Modeling

    Directory of Open Access Journals (Sweden)

    Svetlana М. Yatsun

    2013-01-01

    Full Text Available The article deals with the mathematical modeling of biological diagnosis of complex heterogeneous structure (skin, using non-destructive control method. The mathematical model, describing interaction of the material with electrodynamic vibration generator and sensor system, controlling the propagation of small disturbances was developed. The influence of material model parameters on the spectrum in the course of the propagation of the surface disturbance

  7. Vibrotactile and Vibroacoustic Communications

    DEFF Research Database (Denmark)

    Morrison, Ann; Manresa, Cristina; Knoche, Hendrik Ole

    2017-01-01

    period. Participants wearing the vest (and their pair) completed a set of tasks. We logged use and responses, recorded all activities on video, and conducted post-experiment interviews and questionnaires. Results: The results depicted the participants’ experience, communication and connection while...

  8. TOMS ozone data compared at mesoscale resolution to tropopause heights from the AVE radiosonde network and to VAS radiances over the south-central United States

    Science.gov (United States)

    Chesters, Dennis; Uccellini, Louis; Larko, David

    1987-01-01

    Observations from 1982 are being compared between the Total Ozone Mapping Spectrometer (TOMS), the Atmospheric Variability Experiment (AVE), and the VISSR Atmospheric Sounder (VAS) across Texas and Oklahoma. TOMS data show a significant ozone maximum over northeastern Texas. AVE radiosonde analysis shows tropopause heights with the highest pressure (lowest altitudes) over central Oklahoma accompanied by a mid-level jet across northern Mexico exiting above the Texas-Gulf coast. Corresponding VAS radiances show a dry slot in the middle tropopause across central Texas accompanied by a secondary slot over Oklahoma. The maxima are separated by 100 to 500 km. The impact of TOMS data on tropopause analysis is preliminarily seen as insignificant because TOMS data is not registered with respect to AVE tropopause heights.

  9. Randomized Comparison of the Therapeutic Effect of Acupuncture, Massage, and Tachibana-Style-Method on Stiff Shoulders by Measuring Muscle Firmness, VAS, Pulse, and Blood Pressure

    Directory of Open Access Journals (Sweden)

    Kazuhiro Tachibana

    2012-01-01

    Full Text Available To compare the therapeutic efficacy of acupuncture, massage, and Tachibana-Ryojutsu (one of Japanese traditional body balance therapy techniques (SEITAI, on stiff shoulders, the subjects’ muscle firmness, blood pressure, pulse, VAS, and body temperature were measured before and after the treatment. Forty-seven volunteer subjects gave written informed consent to participate in this study. The subjects were randomly divided into three groups to receive acupuncture, massage, or Tachibana-Ryojutsu. Each therapy lasted for 90 seconds. The acupuncture treatment was applied by a retaining-needle at GB-21, massage was conducted softly on the shoulders, and Tachibana-Ryojutsu treated only the muscles and joints from the legs to buttocks without touching the shoulders or backs. The study indicated that the muscle firmness and VAS of the Tachibana-Ryojutsu group decreased significantly in comparison with the acupuncture and massage groups after treatment.

  10. Ultrastructural aspects of spermatogenesis, testes, and vas deferens in the parthenogenetic tapeworm Atractolytocestus huronensis Anthony, 1958 (Cestoda: Caryophyllidea), a carp parasite from Slovakia.

    Science.gov (United States)

    Bruňanská, Magdaléna; Nebesářová, Jana; Oros, Mikuláš

    2011-01-01

    Spermatogenesis, testes, and vas deferens in the parthenogenetic monozoic tapeworm Atractolytocestus huronensis Anthony, 1958 (Cestoda: Caryophyllidea) from Slovakia, parasitizing the carp Cyprinus carpio L., have been investigated by means of transmission electron microscopy for the first time. The present results show that helminths with parthenogenetic and normal reproduction may share some common spermatology features, e.g., dense cytoplasm of the peripherally localized spermatogonia or a rosette type of spermatogenesis. In contrast to tapeworms with normal reproduction, the most prominent ultrastructural characteristic of the spermatocytes of A. huronensis is fragmentation of their nuclei. This clear feature of cell degeneration might be a consequence of the aberrant first meiotic division. Peripheral cortical microtubules and a single centriole, indicators of the ongoing spermiogenesis, were observed only very rarely in the early spermatids. Characteristics of normal spermiogenesis, i.e., apical dense material in the zone of differentiation in early stages of spermiogenesis, flagellar rotation, and proximo-distal fusion, were never found in the present study. The testes follicles are surrounded by a thin cytoplasmic sheath underlined by a basal lamina. Vas deferens is lined by flat epithelium with numerous surface lamellae and cilia. Mature, functional spermatozoa were not observed in the vas deferens of A. huronensis from Slovakia.

  11. Exogenous 17beta-estradiol blocks alpha and mu but not pi class glutathione S-transferase immunoreactivity in epithelium of Syrian hamster vas deferens.

    Science.gov (United States)

    Hudson, C E; DeHaven, J E; Schulte, B A; Norris, J S

    1999-01-01

    Members of the glutathione S-transferase (GST) family of detoxification enzymes play a role in chemotherapy resistance in certain cancers but have not been directly implicated as agents whose absence may predispose tissues to hormonally induced tumorigenesis. Here we report the development of a polyclonal antiserum to a hamster mu class GST, and immunohistochemical analysis of alpha, mu, and pi class GSTs to study the effects of hormone treatment on their expression in reproductive tract tissues of male golden Syrian hamsters. These animals develop leiomyosarcomas in the vas deferens after treatment with testosterone propionate (TP) and 17beta-estradiol (E2). High levels of all three GST classes were detected throughout the reproductive tract epithelium of control animals. In 100% of the experimental animals, 4 weeks of treatment either with E2 alone, or with E2 plus TP promoted a complete loss of immunostaining for alpha and mu class GSTs, but not for pi class GSTs, only in the epithelial lining of the vas deferens. In contrast, treatment with TP alone resulted in moderate hyperplasia of smooth muscle in the proximal vas deferens, with no cellular atypia and no changes in immunoreactivity of any of the GST classes. The consistent and site-specific nature of these results strongly suggests a functional role for GSTs in hormonally induced carcinogenic process. (J Histochem Cytochem 47:91-98, 1999)

  12. Motor Threshold: A Possible Guide to Optimizing Stimulation Parameters for Motor Cortex Stimulation.

    Science.gov (United States)

    Slotty, Philipp J; Chang, Stephano; Honey, Christopher R

    2015-10-01

    No widely accepted programming guidelines for motor cortex stimulation (MCS) exist. We propose that an individual's effective stimulation voltage can be predicted as their percentage of motor threshold (PMT). Seven patients already successfully treated with MCS for neuropathic pain were included. Patients received stimulation that was the same as their baseline PMT ("medium"), 10% higher ("high") or 10% lower ("low") in a blinded, randomized study. Outcome was assessed after 14 days with the visual analogue scale for pain, the McGill pain questionnaire, and the SF-36 questionnaire. The best treatment response (mean VAS 3.4) was seen with the medium setting which was at a mean of 62% PMT. High and low settings both resulted in a significant increase in pain compared with the medium setting (mean VAS 6.0 and 6.3, respectively) and a significant decrease in SF-36 scores. No significant difference in pain control was observed between the high and low settings. The mean time from changes in treatment settings to reported change in pain level was 2.9 days (±1.0 day). We propose that the PMT represents an important parameter that measures the degree to which MCS may be affecting the motor cortex. A mean PMT of 62% was required for effective pain relief. Higher settings did not result in increased therapeutic efficacy but rather in a significant increase in pain. Targeting therapy to a PMT level may speed initial programming, allow more consistent longitudinal follow-up, and be a basis for a standardized programming paradigm. © 2015 International Neuromodulation Society.

  13. SPINAL CORD STIMULATION IN TREATMENT OF THE NEUROPATHIC PAIN SYNDROMES: INITIAL EXPERIENCE

    Directory of Open Access Journals (Sweden)

    D. A. Rzaev

    2010-01-01

    Full Text Available In the article initial experience of spinal cord stimulation for chronic pain syndromes is described. The trial was done for 62 patients, in 52 cases trial was successful and subcutaneous pulse generator were implanated. Maximal follow-up is 26 months. The level of pain evaluates at VAS. Permanent pain-relieve results were achieved in 46 patients (74,2%. These results correspond to literature data.

  14. Vagus Nerve Stimulation

    Science.gov (United States)

    Vagus nerve stimulation Overview By Mayo Clinic Staff Vagus nerve stimulation is a procedure that involves implantation of a device that stimulates the vagus nerve with electrical impulses. There's one vagus nerve ...

  15. Role of Ca2+-activated K+ channels and Na+-K+-ATPase in prostaglandin E1- and E2-induced inhibition of the adrenergic response in human vas deferens

    OpenAIRE

    Medina Bessó, Pascual; Segarra Irles, Gloria Vicenta; Mauricio Aviñó, María Dolores; Vila Salinas, José María; Chuan Nuez, Pascual; Lluch López, Salvador

    2011-01-01

    Abstract We studied the role of K+ channels and Na+,K+-ATPase in the presynaptic inhibitory effects of prostaglandin E1 (PGE1) and PGE2 on the adrenergic responses of human vas deferens. Furthermore, we determined the effects of increasing extracellular K+ concentrations ([K+]o) and inhibition of Na+,K+-ATPase on neurogenic and norepinephrine -induced contractile responses. Ring segments of the epididymal part of the vas deferens were taken from 45 elective vasectomies and mounted ...

  16. Effect of noni (Morinda citrifolia Linn.) fruit and its bioactive principles scopoletin and rutin on rat vas deferens contractility: an ex vivo study.

    Science.gov (United States)

    Pandy, Vijayapandi; Narasingam, Megala; Kunasegaran, Thubasni; Murugan, Dharmani Devi; Mohamed, Zahurin

    2014-01-01

    This study examined the effect of methanolic extract of Morinda citrifolia Linn. (MMC) and its bioactive principles, scopoletin and rutin, on dopamine- and noradrenaline-evoked contractility in isolated rat vas deferens preparations. MMC (1-40 mg/mL), scopoletin (1-200 μg/mL), and rutin hydrate (0.6-312.6 μg/mL) dose-dependently inhibited the contractility evoked by submaximal concentrations of both dopamine and noradrenaline, respectively. Haloperidol and prazosin, reference dopamine D2, and α 1-adrenoceptors antagonists significantly reversed the dopamine- and noradrenaline-induced contractions, respectively, in a dose-dependent manner. Interestingly, MMC per se at higher doses (60-100 mg/mL) showed dose-dependent contractile response in rat vas deferens which was partially inhibited by high doses of haloperidol but not by prazosin. These results demonstrated the biphasic effects of MMC on dopaminergic system; that is, antidopaminergic effect at lower concentrations (60 mg/mL). However, similar contractile response at high doses of scopoletin (0.5-5 mg/mL) and rutin hydrate (0.5-5 mg/mL) per se was not observed. Therefore, it can be concluded that the bioactive principles of MMC, scopoletin, and rutin might be responsible for the antidopaminergic and antiadrenergic activities of MMC.

  17. Assessment of the Therapeutic Effectiveness of Deep Electromagnetic Stimulation in Patients with Chronic Low Back Pain.

    Science.gov (United States)

    Przedborska, Agnieszka; Misztal, Małgorzata; Raczkowski, Jan W

    2015-10-01

    The study presents the results of the application of deep electromagnetic stimulation (DEMS) therapy in the treatment of low back pain. The study aimed to evaluate and compare pain severity before and after deep electromagnetic stimulation sessions and to assess persistence of the analgesic effect and identify factors which influenced it significantly. The study enrolled a series of 105 consecutive patients with chronic low back pain who underwent a series of 10 sessions of deep electromagnetic stimulation. The effectiveness of the therapy was assessed according to VAS and Laitinen scores. Risk factors significantly affecting the stability of analgesic effect after DEMS therapy were identified using the Cox regression model. Statistically significant pain relief was observed after deep electromagnetic therapy. Both the Laitinen and VAS scales demonstrated the reduction in pain intensity by half (Me (IQR): 6 (5-9) before the therapy vs. 3 (24) afterwards, ppain recurred in 84 (80%) patients. Pain recurrence within a year after the therapy was stimulated in a statistically significant manner by pain duration (HR=1.032, 95% CI: 0.988-1.078; p=0.032) and the co-occurrence of degenerative joint disease (HR=5.521, 95%CI: 2.905-10.493; p=0.001). 1. Deep electromagnetic stimulation is an effective treatment in patients with chronic low back pain. 2. The degree of effectiveness of this modality in the longer term depends on the cause and duration of pain.

  18. Prediction of the vibroacoustic behavior of a submerged shell with non-axisymmetric internal substructures by a condensed transfer function method

    Science.gov (United States)

    Meyer, V.; Maxit, L.; Guyader, J.-L.; Leissing, T.

    2016-01-01

    The vibroacoustic behavior of axisymmetric stiffened shells immersed in water has been intensively studied in the past. On the contrary, little attention has been paid to the modeling of these shells coupled to non-axisymmetric internal frames. Indeed, breaking the axisymmetry couples the circumferential orders of the Fourier series and considerably increases the computational costs. In order to tackle this issue, we propose a sub-structuring approach called the Condensed Transfer Function (CTF) method that will allow assembling a model of axisymmetric stiffened shell with models of non-axisymmetric internal frames. The CTF method is developed in the general case of mechanical subsystems coupled along curves. A set of orthonormal functions called condensation functions, which depend on the curvilinear abscissa along the coupling line, is considered. This set is then used as a basis for approximating and decomposing the displacements and the applied forces at the line junctions. Thanks to the definition and calculation of condensed transfer functions for each uncoupled subsystem and by using the superposition principle for passive linear systems, the behavior of the coupled subsystems can be deduced. A plane plate is considered as a test case to study the convergence of the method with respect to the type and the number of condensation functions taken into account. The CTF method is then applied to couple a submerged non-periodically stiffened shell described using the Circumferential Admittance Approach (CAA) with internal substructures described by Finite Element Method (FEM). The influence of non-axisymmetric internal substructures can finally be studied and it is shown that it tends to increase the radiation efficiency of the shell and can modify the vibrational and acoustic energy distribution.

  19. Vibro-acoustic modeling and analysis of a coupled acoustic system comprising a partially opened cavity coupled with a flexible plate

    Science.gov (United States)

    Shi, Shuangxia; Su, Zhu; Jin, Guoyong; Liu, Zhigang

    2018-01-01

    This paper is concerned with the modeling and solution method of a three-dimensional (3D) coupled acoustic system comprising a partially opened cavity coupled with a flexible plate and an exterior field of semi-infinite size, which is ubiquitously encountered in architectural acoustics and is a reasonable representation of many engineering occasions. A general solution method is presented to predict the dynamic behaviors of the three-dimensional (3D) acoustic coupled system, in which the displacement of the plate and the sound pressure in the cavity are respectively constructed in the form of the two-dimensional and three-dimensional modified Fourier series with several auxiliary functions introduced to ensure the uniform convergence of the solution over the entire solution domain. The effect of the opening is taken into account via the work done by the sound pressure acting at the coupling aperture that is contributed from the vibration of particles on the acoustic coupling interface and on the structural-acoustic coupling interface. Both the acoustic coupling between finite cavity and exterior field and the structural-acoustic coupling between flexible plate and interior acoustic field are considered in the vibro-acoustic modeling of the three-dimensional acoustic coupled acoustic system. The dynamic responses of the coupled structural-acoustic system are obtained using the Rayleigh-Ritz procedure based on the energy expressions for the coupled system. The accuracy and effectiveness of the proposed method are validated through numerical examples and comparison with results obtained by the boundary element analysis. Furthermore, the influence of the opening and the cavity volume on the acoustic behaviors of opened cavity system is studied.

  20. Tibial nerve stimulation with a miniature, wireless stimulator in chronic peripheral neuropathic pain

    Directory of Open Access Journals (Sweden)

    Sokal P

    2017-03-01

    Full Text Available Paweł Sokal,1 Marek Harat,2 Piotr Zieliński,3 Sara Kierońska1 1Department of Neurosurgery, Military Research Hospital, Bydgoszcz, 2Department of Public Health, Ludwik Rydygier Collegium Medicum, Bydgoszcz, Nicolaus Copernicus University, Toruń, 3Department of Sports Medicine, University of Physical Education and Sport, Gdansk, Poland Abstract: Peripheral neuropathic pain (PNP and complex regional pain syndrome (CRPS can be effectively treated with peripheral nerve stimulation. In this clinical trial report, effectiveness of novel, miniature, wirelessly controlled microstimulator of tibial nerve in PNP and CRPS was evaluated. In this pilot study the average preoperative visual analog scale (VAS score in six patients was 7.5, with 1, 3 and 6 months: 2.6 (p=0.03, 1.6 (p=0.03, and 1.3 (p=0.02, respectively. The mean average score in the six patients a week preceding the baseline visit was 7.96, preceding the 1, 3 and 6 month visits: 3.32 (p=0.043, 3.65 (p=0.045, and 2.49 (p=0.002, respectively. The average short-form McGill pain score before surgery was 23.8, and after 1, 3 and 6 months it was 11.0 (p=0.45, 6.3 (p=0.043, and 4.5 (p=0.01, respectively. Applied therapy caused a reduction of pain immediately after its application and clinical improvement was sustained on a similar level in all patients for six months. No complications of the treatment were observed. Intermittent tibial nerve stimulation by using a novel, miniature, wirelessly controlled device can be effective and feasible in PNP and CRPS. It is a safe, minimally invasive, and convenient neuromodulative method. Keywords: tibial nerve stimulation, peripheral nerve stimulation, miniature stimulator, peripheral neuropathic pain, complex regional pain syndrome 

  1. High-frequency, high-intensity transcutaneous electrical nerve stimulation as treatment of pain after surgical abortion.

    Science.gov (United States)

    Platon, B; Andréll, P; Raner, C; Rudolph, M; Dvoretsky, A; Mannheimer, C

    2010-01-01

    The aim of the study was to compare the pain-relieving effect and the time spent in the recovery ward after treatment with high-frequency, high-intensity transcutaneous electrical nerve stimulation (TENS) or intravenous (IV) conventional pharmacological treatment after surgical abortion. Two-hundred women who underwent surgical abortion and postoperatively reported a visual analogue scale (VAS) pain score3 were included. The patients were randomised to TENS or conventional pharmacological treatment for their postoperative pain. The TENS treatment was given with a stimulus intensity between 20 and 60 mA during 1 min and repeated once if insufficient pain relief (VAS3). In the conventional pharmacological treatment group, a maximum dose of 100 microg fentanyl was given IV. There was no difference between the groups with regard to pain relief according to the VAS pain score (TENS=VAS 1.3 vs. IV opioids=VAS 1.6; p=0.09) upon discharge from the recovery ward. However, the patients in the TENS group spent shorter time (44 min) in the recovery ward than the conventional pharmacological treatment group (62 min; p<0.0001). The number of patients who needed additional analgesics in the recovery ward was comparable in both groups, as was the reported VAS pain score upon leaving the hospital (TENS=2.0 vs. conventional pharmacological treatment=1.8, NS). These results suggest that the pain-relieving effect of TENS seems to be comparable to conventional pharmacological treatment with IV opioids. Hence, TENS may be a suitable alternative to conventional pain management with IV opioids after surgical abortion. Copyright 2009 International Association for the Study of Pain. Published by Elsevier B.V. All rights reserved.

  2. QALY weights for diabetic retinopathy--a comparison of health state valuations with HUI-3, EQ-5D, EQ-VAS, and TTO.

    Science.gov (United States)

    Heintz, Emelie; Wiréhn, Ann-Britt; Peebo, Beatrice Bourghardt; Rosenqvist, Ulf; Levin, Lars-Åke

    2012-05-01

    To estimate quality-adjusted life-year weights for patients with diabetic retinopathy by using various methods and to investigate the empirical validity of the different measures. The study population comprised 152 patients with diabetes in Östergötland County, Sweden. Participants were interviewed by telephone by using the time trade-off (TTO) method and a visual analogue scale (EQ-VAS) (direct valuations) as well as the EuroQol five-dimensional questionnaire (EQ-5D) and the health utilities index mark 3 (HUI-3) (indirect valuations). The quality-adjusted life-year weights were adjusted for potential confounders by using analysis of covariance. The empirical validity of the measures was examined by testing their ability to detect hypothetical differences between severity levels of diabetic retinopathy and by investigating the correlation between the measures and the 25-item National Eye Institute Visual Function Questionnaire (NEI VFQ-25). All measures detected significant differences in scores between patient groups classified according to visual impairment in the better eye (analysis of covariance, P VAS detected significant differences between patient groups classified according to visual impairment or pathological progression in the worse eye. HUI-3 recorded a difference of 0.43 in values between normal vision and blindness in the better eye, which was more than twice the differences captured by the other measures (0.15-0.20). In addition, HUI-3 showed the highest correlation with NEI VFQ-25 (r = 0.54; P < 0.001). In cost-utility analyses, the choice of quality-adjusted life-year measure may affect whether an intervention is considered cost-effective. Furthermore, if decisions are to be based on values from the general public, HUI-3 can be recommended for cost-utility analyses of interventions directed at diabetic retinopathy. Copyright © 2012 International Society for Pharmacoeconomics and Outcomes Research (ISPOR). Published by Elsevier Inc. All rights

  3. Endovascular Treatment of Pelvic Congestion Syndrome: Visual Analog Scale (VAS) Long-Term Follow-up Clinical Evaluation in 202 Patients

    Energy Technology Data Exchange (ETDEWEB)

    Laborda, Alicia, E-mail: alaborda@unizar.es; Medrano, Joaquin, E-mail: oauieao@gmail.com [University of Zaragoza, Group of Research in Minimally Invasive Techniques Research (GITMI) (Spain); Blas, Ignacio de, E-mail: deblas@unizar.es [University of Zaragoza, Edificio Hospital Veterinario, Department of Animal Pathology (Unit of Infectious Diseases and Epidemiology) (Spain); Urtiaga, Ignacio, E-mail: info@doctorurtiaga.com [Hospital Clinico Universitario ' Lozano Blesa' , Department of Vascular Surgery (Spain); Carnevale, Francisco Cesar, E-mail: fcarnevale@uol.com.br [University of Sao Paulo, Medical School, Interventional Radiology (Brazil); Gregorio, Miguel A. de, E-mail: mgregori@unizar.es [University of Zaragoza, Group of Research in Minimally Invasive Techniques Research (GITMI) (Spain)

    2013-08-01

    PurposeThis study was designed to evaluate the clinical outcome and patients' satisfaction after a 5 year follow-up period for pelvic congestion syndrome (PCS) coil embolization in patients who suffered from chronic pelvic pain that initially consulted for lower limb venous insufficiency.MethodsA total of 202 patients suffering from chronic pelvic pain were recruited prospectively in a single center (mean age 43.5 years; range 27-57) where they were being treated for lower limb varices. Inclusion criteria were: lower limb varices and chronic pelvic pain (>6 months), >6 mm pelvic venous caliber in ultrasonography, and venous reflux or presence of communicating veins. Both ovarian and hypogastric veins were targeted for embolization. Pain level was assessed before and after embolotherapy and during follow-up using a visual analog scale (VAS). Technical and clinical success and recurrence of leg varices were studied. Patients completed a quality questionnaire. Clinical follow-up was performed at 1, 3, and 6 months and every year for 5 years.ResultsTechnical success was 100 %. Clinical success was achieved in 168 patients (93.85 %), with complete disappearance of symptoms in 60 patients (33.52 %). Pain score (VAS) was 7.34 {+-} 0.7 preprocedural versus 0.78 {+-} 1.2 at the end of follow-up (P < 0.0001). Complications were: groin hematoma (n = 6), coil migration (n = 4), and reaction to contrast media (n = 1). Twenty-three cases presented abdominal pain after procedure. In 24 patients (12.5 %), there was recurrence of their leg varices within the follow-up. The mean degree of patients' satisfaction was 7.4/9.ConclusionsCoil embolization of PCS is an effective and safe procedure, with high clinical success rate and degree of satisfaction.

  4. ALTERATION OF MUSCLE FUNCTION AFTER ELECTRICAL STIMULATION BOUT OF KNEE EXTENSORS AND FLEXORS

    Directory of Open Access Journals (Sweden)

    Marc Vanderthommen

    2012-12-01

    Full Text Available The purpose was to study the effects on muscle function of an electrical stimulation bout applied unilaterally on thigh muscles in healthy male volunteers. One group (ES group, n = 10 received consecutively 100 isometric contractions of quadriceps and 100 isometric contractions of hamstrings (on-off ratio 6-6 s induced by neuromuscular electrical stimulations (NMES. Changes in muscle torque, muscle soreness (0-10 VAS, muscle stiffness and serum creatine kinase (CK activity were assessed before the NMES exercise (pre-ex as well as 24h (d+1, 48h (d+2 and 120h (d+5 after the bout. A second group (control group, n = 10 were submitted to the same test battery than the ES group and with the same time-frame. The between-group comparison indicated a significant increase in VAS scores and in serum levels of CK only in the ES group. In the ES group, changes were more pronounced in hamstrings than in quadriceps and peaked at d+2 (quadriceps VAS scores = 2.20 ± 1.55 a.u. (0 at pre-ex; hamstrings VAS scores = 3.15 ± 2.14 a.u. (0 at pre-ex; hip flexion angle = 62 ± 5° (75 ± 6° at pre-ex; CK activity = 3021 ± 2693 IU·l-1 (136 ± 50 IU·l-1 at pre-ex. The results of the present study suggested the occurrence of muscle damage that could have been induced by the peculiar muscle recruitment in NMES and the resulting overrated mechanical stress. The sensitivity to the damaging effects of NMES appeared higher in the hamstrings than in quadriceps muscles

  5. Spinal cord stimulation

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/007560.htm Spinal cord stimulation To use the sharing features on this page, please enable JavaScript. Spinal cord stimulation is a treatment for pain that uses a ...

  6. Feldspar, Infrared Stimulated Luminescence

    DEFF Research Database (Denmark)

    Jain, Mayank

    2014-01-01

    This entry primarily concerns the characteristics and the origins of infrared-stimulated luminescence in feldspars.......This entry primarily concerns the characteristics and the origins of infrared-stimulated luminescence in feldspars....

  7. Effect of Deep Intramuscular Stimulation and Transcranial Magnetic Stimulation on Neurophysiological Biomarkers in Chronic Myofascial Pain Syndrome.

    Science.gov (United States)

    Medeiros, Liciane F; Caumo, Wolnei; Dussán-Sarria, Jairo; Deitos, Alicia; Brietzke, Aline; Laste, Gabriela; Campos-Carraro, Cristina; de Souza, Andressa; Scarabelot, Vanessa L; Cioato, Stefania G; Vercelino, Rafael; de Castro, Alexandre L; Araújo, Alex Sander; Belló-Klein, Adriane; Fregni, Felipe; Torres, Iraci L S

    2016-01-01

    The aim was to assess the neuromodulation techniques effects (repetitive transcranial magnetic stimulation [rTMS] and deep intramuscular stimulation therapy [DIMST]) on pain intensity, peripheral, and neurophysiological biomarkers chronic myofascial pain syndrome (MPS) patients. Randomized, double blind, factorial design, and controlled placebo-sham clinical trial. Clinical trial in the Laboratory of Pain and Neuromodulation at Hospital de Clínicas de Porto Alegre (NCT02381171). We recruited women aged between 19- and 75-year old, with MPS diagnosis. Patients were randomized into four groups: rTMS + DIMST, rTMS + sham-DIMST, sham-rTMS + DIMST, sham-rTMS + sham-DIMST; and received 10 sessions for 20 minutes each one (rTMS and DIMST). Pain was assessed by visual analogue scale (VAS); neurophysiological parameters were assessed by transcranial magnetic stimulation; biochemical parameters were: BDNF, S100β, lactate dehydrogenase, inflammatory (TNF-α, IL6, and IL10), and oxidative stress parameters. We observed the pain relief assessed by VAS immediately assessed before and after the intervention (P 0.05). Our findings add additional evidence about rTMS and DIMST in relieving pain in MPS patients without synergistic effect. No peripheral biomarkers reflected the analgesic effect of both techniques; including those related to cellular damage. Additionally, one neurophysiological parameter (increased MEP amplitude) needs to be investigated. Published by Oxford University Press on behalf of the American Academy of Pain Medicine. 2016. This work is written by US Government employees and is in the public domain in the US.

  8. Predicting the conditions under which vibroacoustic resonances with external periodic loads occur in the primary coolant circuits of VVER-based NPPs

    Science.gov (United States)

    Proskuryakov, K. N.; Fedorov, A. I.; Zaporozhets, M. V.

    2015-08-01

    The accident at the Japanese Fukushima Daiichi nuclear power plant (NPP) caused by an earthquake showed the need of taking further efforts aimed at improving the design and engineering solutions for ensuring seismic resistance of NPPs with due regard to mutual influence of the dynamic processes occurring in the NPP building structures and process systems. Resonance interaction between the vibrations of NPP equipment and coolant pressure pulsations leads to an abnormal growth of dynamic stresses in structural materials, accelerated exhaustion of equipment service life, and increased number of sudden equipment failures. The article presents the results from a combined calculation-theoretical and experimental substantiation of mutual amplification of two kinds of external periodic loads caused by rotation of the reactor coolant pump (RCP) rotor and an earthquake. The data of vibration measurements at an NPP are presented, which confirm the predicted multiple amplification of vibrations in the steam generator and RCP at a certain combination of coolant thermal-hydraulic parameters. It is shown that the vibration frequencies of the main equipment may fall in the frequency band corresponding to the maximal values in the envelope response spectra constructed on the basis of floor accelerograms. The article presents the results from prediction of conditions under which vibroacoustic resonances with external periodic loads take place, which confirm the occurrence of additional earthquake-induced multiple growth of pressure pulsation intensity in the steam generator at the 8.3 Hz frequency and additional multiple growth of vibrations of the RCP and the steam generator cold header at the 16.6 Hz frequency. It is shown that at the elastic wave frequency equal to 8.3 Hz in the coolant, resonance occurs with the frequency of forced vibrations caused by the rotation of the RCP rotor. A conclusion is drawn about the possibility of exceeding the design level of equipment vibrations

  9. Brain Stimulation in Addiction.

    Science.gov (United States)

    Salling, Michael C; Martinez, Diana

    2016-11-01

    Localized stimulation of the human brain to treat neuropsychiatric disorders has been in place for over 20 years. Although these methods have been used to a greater extent for mood and movement disorders, recent work has explored brain stimulation methods as potential treatments for addiction. The rationale behind stimulation therapy in addiction involves reestablishing normal brain function in target regions in an effort to dampen addictive behaviors. In this review, we present the rationale and studies investigating brain stimulation in addiction, including transcranial magnetic stimulation, transcranial direct current stimulation, and deep brain stimulation. Overall, these studies indicate that brain stimulation has an acute effect on craving for drugs and alcohol, but few studies have investigated the effect of brain stimulation on actual drug and alcohol use or relapse. Stimulation therapies may achieve their effect through direct or indirect modulation of brain regions involved in addiction, either acutely or through plastic changes in neuronal transmission. Although these mechanisms are not well understood, further identification of the underlying neurobiology of addiction and rigorous evaluation of brain stimulation methods has the potential for unlocking an effective, long-term treatment of addiction.

  10. Heterogeneous spectrum of mutations in CFTR gene from Indian patients with congenital absence of the vas deferens and their association with cystic fibrosis genetic modifiers.

    Science.gov (United States)

    Sharma, H; Mavuduru, R S; Singh, S K; Prasad, R

    2014-09-01

    Cystic fibrosis (CF) is usually considered a rare disease in the Indian population. Two studies have reported on the frequency of cystic fibrosis transmembrane conductance regulator (CFTR) gene mutations in Indian males with congenital absence of the vas deferens (CAVD), however, data on the spectrum of CFTR gene mutations are still lacking. Therefore, the present study was designed to identify the spectrum of CFTR gene mutations as well as to investigate an association of CF genetic modifiers in the penetrance of CAVD in infertile Indian men. A total of 60 consecutive infertile males with a diagnosis of CAVD were subjected to CFTR gene analysis which revealed 13 different CFTR gene mutations and 1 intronic variant that led to aberrant splicing. p.Phe508del (n = 16) and p.Arg117His (n = 4) were among the most common severe forms of CFTR mutations identified. The IVS8-T5 allele, which is considered as a mild form of CFTR mutation, was found with an allelic frequency of 28.3%. Eight novel mutations were also identified in the CFTR gene from our patient cohort. It is noteworthy that the spectrum of CFTR gene mutation is heterogeneous, with exon 4 and exon 11 as hot spot regions. Moreover, we also found an association of the CF genetic modifiers, viz., transforming growth factor (TGF)-β1 and endothelial receptor type-A (EDNRA) genes with the CAVD phenotype. The findings are of considerable clinical significance because men suffering from infertility due to CAVD can decide to use artificial reproduction technology. The children of men with CAVD are at risk of carrying CFTR mutations; therefore, genetic counseling is a crucial step for such patients. With special reference to developing countries, such as India, where whole gene sequencing is not feasible, the outcome of our study will make the screening procedure for CFTR gene simpler and more cost-effective as we have identified hot spot regions of the CFTR gene which are more prone to mutation in Indian males with

  11. Intravaginal stimulation randomized trial.

    Science.gov (United States)

    Smith, J J

    1996-01-01

    The effectiveness of intravaginal electrical stimulation was compared to standard therapy in the treatment of genuine stress urinary incontinence and detrusor instability. A total of 57 women with urinary incontinence was evaluated with video urodynamics and voiding diaries before and after treatment. Of the women 18 with stress urinary incontinence were randomized to electrical stimulation or Kegel exercise and 38 with detrusor instability were randomized to anticholinergic therapy or electrical stimulation. Of patients using electrical stimulation in the stress urinary incontinence group 66% improved and 72% of the patients with detrusor instability treated with electrical stimulation improved. These rates were not statistically significant when compared to traditional therapy. Electrical stimulation is safe and at least as effective as properly performed Kegel and anticholinergic therapy in the treatment of stress urinary incontinence and detrusor instability.

  12. CFTR Mutation Analysis of a Caucasian Father with Congenital Bilateral Absence of Vas Deferens, a Taiwanese Mother, and Twins Resulting from ICSI Procedure

    Directory of Open Access Journals (Sweden)

    Han-Sun Chiang

    2008-09-01

    Full Text Available Cystic fibrosis (CF, caused by mutations in the cystic fibrosis transmembrane conductance regulator (CFTR gene, is one of the most common autosomal recessive diseases in Caucasians. We screened for the CFTR gene mutation in a Caucasian father with congenital bilateral absence of the vas deferens (CBAVD, a Taiwanese mother, and twins resulting from an intracytoplasmic single sperm injection (ICSI procedure. DNA fragments that showed abnormal banding patterns on temporal temperature gradient gel electrophoresis analysis followed by analysis of DNA sequence was used. The Caucasian father with CBAVD had ΔF508 and p.L375F mutations. The two children were heterozygous for the ΔF508 and p.L375F mutations, respectively. Mutation analysis of the CFTR gene should always be recommended for infertile couples seeking ICSI. The possibility of the children resulting from ICSI being a victim or carrier of CBAVD or CF, especially when the father is Caucasian with CBAVD, should be discussed during genetic counseling.

  13. Effect of transcutaneous electrical nerve stimulation for pain control after total knee arthroplasty: A systematic review and meta-analysis.

    Science.gov (United States)

    Zhu, Yongjun; Feng, Yuxing; Peng, Lihua

    2017-09-21

    Transcutaneous electrical nerve stimulation is a possible adjunctive therapy to pharmacological treatment for controlling pain after total knee arthroplasty. However, the results are controversial. A systematic review and meta-analysis was conducted to explore the effect of transcutaneous electrical nerve stimulation on patients with total knee arthroplasty. PubMed, Embase, Web of Science, EBSCO, and Cochrane Library databases were searched systematically. Randomized controlled trials assessing the effect of transcutaneous electrical nerve stimulation on patients with total knee arthroplasty were included. Two investigators independently searched articles, extracted data, and assessed the quality of included studies. Primary outcome was visual analogue scale (VAS) score over a period of 24 h. Meta-analysis was performed using a random-effect model. Six randomized controlled trials involving 529 patients were included in the meta-analysis. Overall, compared with control intervention, transcutaneous electrical nerve stimulation supplementation intervention was found to significantly reduce VAS scores and total postoperative morphine dose over a period of 24 h, and to improve active range of knee motion (standard mean difference (SMD) = 0.37; 95% confidence interval (95% CI) = 0.06-0.68; p = 0.02), but had no effect on VAS scores at 2 weeks (SMD = 0.20; 95% CI = -0.07 to 0.48; p = 0.15). Compared with control intervention, transcutaneous electrical nerve stimulation supplementation intervention was found to significantly reduce pain and morphine requirement over a period of 24 h and to promote functional recovery in patients who have undergone total knee arthroplasty.

  14. Establishing Minimal Clinically Important Difference of Spinal Cord Stimulation Therapy in Post-Laminectomy Syndrome.

    Science.gov (United States)

    Paul, Alexandra R; Kumar, Vignessh; Roth, Steven; Gooch, M Reid; Pilitsis, Julie G

    2017-12-01

    The concept of minimum clinically important difference (MCID) has been shown to be effective in spine surgery to differentiate between clinically insignificant and significant improvements as determined by the patient. The MCID for spinal cord stimulation (SCS) to date has not been established. We sought to determine the MCID for SCS therapy for failed laminectomy syndromes. Preoperative and 6-mo outcomes were assessed prospectively, including the Oswestry Disability Index (ODI), Beck Depression Inventory (BDI), and McGill and Visual Analog Survey questionnaires. Patients were asked: (1) are you satisfied with SCS therapy and (2) would you have the surgery again. Four methods of calculating the MCID were utilized. Forty-eight patients who underwent placement of an SCS between 2012 and 2014 were reviewed. The 4 calculation methods yielded a range of outcome scores (ODI 8.2-13.3, BDI 3.2-7, McGill 0.3-1.3, and Visual Analog Scale [VAS] 1.2-3.7). The maximum area under the curve was observed for the ODI, BDI, and VAS (0.73, 0.81, and 0.89, respectively), which signifies acceptable accuracy in distinguishing responders from nonresponders with the receiver operating characteristic method and suggests that VAS may be the most sensitive in determining meaningful change for the patient. The MCID for SCS placement was calculated using 4 different methods. The results are similar to calculations for the MCID for many lumbar and cervical procedures done for pain. Our results suggest that an improvement of 1.2 to 3.7 points on the VAS scale and 8.2 to 13.3 points on the ODI is clinically meaningful to the patient. Further defining the MCID for SCS therapy will remain of utmost importance in order to justify the cost of the procedure.

  15. Additional effects of transcranial direct-current stimulation and trigger-point injection for treatment of myofascial pain syndrome: a pilot study with randomized, single-blinded trial.

    Science.gov (United States)

    Choi, Yoon-Hee; Jung, Sung-Jin; Lee, Chang Han; Lee, Shi-Uk

    2014-09-01

    Chronic pain caused by myofascial pain syndrome (MPS) results in generalized and debilitating conditions. Trigger-point injection (TPI) is the mainstay of MPS management to reduce acute and localized pain. Other adjunctive intervention to modulate the central pain pathway might be helpful if they are combined with TPI. Transcranial direct-current stimulation (tDCS), which is a form of neurostimulation, has been reported to be safe and effective in treating chronic pain by changing cortical excitability. To determine whether there is an additional effect of tDCS and TPI to reduce pain in patients with MPS. Twenty-one patients with newly diagnosed MPS of shoulder girdle muscles. Patients were randomly assigned into 1 of 3 groups (2 active and 1 sham stimulation groups) and received TPI. Immediately after TPI, tDCS (2 mA for 20 minutes on 5 consecutive days) was administered. For the active stimulation groups, tDCS was applied over 2 different locations (primary motor cortex and dorsolateral prefrontal cortex [DLPFC]). Visual analogue scale (VAS), Pain Threshold Test, and short form of the McGill Pain Questionnaire were measured before and immediately after stimulation for 5 consecutive days. The mean VAS values were decreased in all three groups after 5 days. There was a significant change between before and after stimulation only in the DLPFC group. The significant change in the mean VAS value was shown from after the second stimulation session (p=0.031), and this remained significant until the last stimulation session (p=0.027). This study suggests that tDCS over DLPFC may have additional effects with TPI to reduce pain in patients with MPS. tDCS over DLPFC can be used to reverse central pain pathway by modulating cortical plasticity.

  16. Effectiveness of transcutaneous electrical nerve stimulation and microcurrent electrical nerve stimulation in bruxism associated with masticatory muscle pain--a comparative study.

    Science.gov (United States)

    Rajpurohit, Bharat; Khatri, Subhash M; Metgud, Deepa; Bagewadi, Anjana

    2010-01-01

    To compare the effectiveness of transcutaneous electrical nerve stimulation (TENS) and microcurrent electrical nerve stimulation (MENS) on masticatory muscles pain bruxism patient. A total of 60 subjects with the clinical diagnosis of bruxism were randomly allocated to two study groups. Group A received TENS (50 Hz, pulse width 0.5 mSec, intensity 0-60 mA for 20 minutes for a period of seven days) and Group B received MENS (0.5 Hz, intensity 1,000 muA for 20 minutes for a period of seven days). The outcome measures were assessed in term of Visual Analog Scale (VAS) and digital pressometer of 2 Kgf. The study showed significant change in intensity of pain as per VAS score ( P

  17. Effectiveness of transcutaneous electrical nerve stimulation and microcurrent electrical nerve stimulation in bruxism associated with masticatory muscle pain - A comparative study

    Directory of Open Access Journals (Sweden)

    Rajpurohit Bharat

    2010-01-01

    Full Text Available Objectives: To compare the effectiveness of transcutaneous electrical nerve stimulation (TENS and microcurrent electrical nerve stimulation (MENS on masticatory muscles pain bruxism patient. Materials and Methods : A total of 60 subjects with the clinical diagnosis of bruxism were randomly allocated to two study groups. Group A received TENS (50 Hz, pulse width 0.5 mSec, intensity 0-60 mA for 20 minutes for a period of seven days and Group B received MENS (0.5 Hz, intensity 1,000 μA for 20 minutes for a period of seven days. The outcome measures were assessed in term of Visual Analog Scale (VAS and digital pressometer of 2 Kgf. Results : The study showed significant change in intensity of pain as per VAS score ( P ≤ 0.0001 and tenderness as per digital pressometer ( P ≤ 0.0001. Conclusion : MENS could be used as an effective pain-relieving adjunct to TENS in the treatment of masticatory muscle pain due to bruxism.

  18. A HOMILY OF MEISTER ECKHART PREACHED IN THE ACADEMY OF PARIS ON THE FEAST DAY OF SAINT AUGUSTINE («VAS AURI SOLIDUM»

    Directory of Open Access Journals (Sweden)

    Yevgeniy Shilov

    2013-02-01

    Full Text Available This article is devoted to the study of a little known homily of Meister Eckhart («Vas auri solidum» which he preached on Saint Augustine’s feast day in Paris. Before including the translation of this discourse, the author discusses the specific nature of the so-called academic homily. Preaching a homily was regarded as one of the obligations of a university professor of the time and this task was regulated according to strict guidelines and requirements. Such a homily possessed a specific structure. The author explains its main requirement. This type of homily was meant to explain and interpret a chosen text taken from Holy Scripture. Meister Eckhart actually planned to compose an extended three-part work combining elements of philosophy and theology which was to be known as his Opus tripartitum. One of its parts was to be a collection of model homilies (Opus sermonus. He began this work but did not finish it. Although we today possess only a few sketches and outlines of the Latin homilies of Meister Eckhart, which themselves are characterised by their lack of structure, they provide an excellent understanding of the mind of their author as well as rare insight into the place of Saint Augustine as a master of scholastic thought. In addition, this homily provides the only indication of the place of birth of the renowned mediaeval author. After an in-depth study of the text of the homily, the author concludes that Meister Eckhart borrowed his outline and system of classification from the School of Chartres and especially from Clarembald of Arras, an interpreter of Boethius. Using these sources, Eckhart formulated his idea of the two ways of knowing God: the way of ethics (Augustine and the way of metaphysics (Aristotle, Dionysius the Areopagite and Boethius

  19. Cerebellar stimulation in ataxia.

    Science.gov (United States)

    Groiss, Stefan Jun; Ugawa, Yoshikazu

    2012-06-01

    The cerebellum plays an important role in movement execution and motor control by modulation of the primary motor cortex (M1) through cerebello-thalamo-cortical connections. Transcranial magnetic stimulation (TMS) allows direct investigations of neural networks by stimulating neural structures in humans noninvasively. The motor evoked potential to single-pulse TMS of M1 is used to measure the motor cortical excitability. A conditioning stimulus over the cerebellum preceding a test stimulus of the contralateral M1 enables us to study the cerebellar regulatory functions on M1. In this brief review, we describe this cerebellar stimulation method and its usefulness as a diagnostic tool in clinical neurophysiology.

  20. Stimulants and narcotic drugs.

    Science.gov (United States)

    King, P; Coleman, J H

    1987-04-01

    This article focuses on the use of stimulant and narcotic drugs, as well as lookalike preparations that are subject to abuse. There is a brief discussion of the pharmacology of these agents, demographic use patterns, and treatment modalities.

  1. Geothermal Well Stimulation

    Energy Technology Data Exchange (ETDEWEB)

    Campbell, D. A.; Morris, C. W.; Sinclair, A. R.; Hanold, R. J.; Vetter, O. J.

    1981-03-01

    The stimulation of geothermal wells presents some new and challenging problems. Formation temperatures in the 300-600 F range can be expected. The behavior of stimulation fluids, frac proppants, and equipment at these temperatures in a hostile brine environment must be carefully evaluated before performance expectations can be determined. In order to avoid possible damage to the producing horizon of the formation, high temperature chemical compatibility between the in situ materials and the stimulation materials must be verified. Perhaps most significant of all, in geothermal wells the required techniques must be capable of bringing about the production of very large amounts of fluid. This necessity for high flow rates represents a significant departure from conventional petroleum well stimulation and demands the creation of very high near-wellbore permeability and/or fractures with very high flow conductivity.

  2. ATV Light MDPS Vibroacoustic Test

    Science.gov (United States)

    Destefanis, S.; Busa, F.; Ullio, R.

    2012-07-01

    Back in late 2010, the ATV (Automated Transfer Vehicle) program opted for the adoption of lighter MDPS (Meteoroid and Debris Protection Shield) panels, to be installed on future ATV units, starting from A TV#3. The rationale behind such decision was to save as much mass as possible, while keeping the MDPS design compliant to its requirements. One of the most critical issues was demonstrating that the installation of thinner MDPS panels (0.0012m thickness instead of 0.0016m) did not induce significant impacts on the currently defined ATV environments. If that had been the case, in fact, the proposed modification to the MDPS panels design might have been rejected, or anyway a costly and long analysis process at system level might have been necessary, to verify all ATV internal equipment environmental compatibility. Such detailed analysis cycle was not compatible with the program tight schedule.

  3. Vibroacoustic characteristics of mine locomotives

    Energy Technology Data Exchange (ETDEWEB)

    Chigirinskii, S.E.; Ponomarev, N.S.; Leiman, Ya.A.

    1982-11-01

    The paper discusses noise pollution caused by locomotives used for mine haulage in underground mining. Noise pollution in a mine working and at the driver working place is measured. Mechanical vibrations of the floor in the driver cab are also determined. Noise pollution and mechanical vibrations of 3 locomotive types are comparatively evaluated: the AM-8D electric locomotive, the GR-4 inertia-type locomotive and the 1D-8 diesel locomotive. The results of investigations are shown in 2 tables. The inertia-type locomotive causes the most intensive noise pollution. Noise pollution of the diesel locomotive has been successfully suppressed by a system of shock absorbers. The following methods for noise and vibration control are discussed: use of soundproof cabs, damping vibrations at the driver's seat, use of motors with noise abatement systems and shock absorbers. (In Russian)

  4. Intraoperative Retrograde Perfusion Sphincterometry to Evaluate Efficacy of Autologous Vas Deferens 6-Branch Suburethral Sling to Properly Restore Sphincteric Apparatus During Robot-Assisted Radical Prostatectomy.

    Science.gov (United States)

    Cestari, Andrea; Soranna, Davide; Zanni, Giuseppe; Zambon, Antonella; Zanoni, Matteo; Sangalli, Mattia; Ghezzi, Massimo; Fabbri, Fabio; Sozzi, Francesco; Dell'Acqua, Vincenzo; Rigatti, Patrizio

    2017-09-01

    The aim of this study is to describe (urodynamically) the effect of the use of a 6-branch autologous suburethral sling, made with absorbable sutures and vas deferens, to support the bladder neck and urethra during robot-assisted laparoscopic prostatectomy (RALP) to improve early urinary continence (EUC) recovery. Retrograde leak point pressure (RLPP) was intraoperatively evaluated, by means of retrograde perfusion sphincterometry (RPS), in 77 patients (mean age ± standard deviation [SD]: 65.64 ± 7.23 years, mean body mass index ± SD: 26.69 ± 3.89) scheduled to undergo RALP at our institution. RLPP was evaluated before (RLPPb) and after pneumoperitoneum induction (RLPPp). RLPP was then evaluated after urethrovesical anastomosis (RLPPa) and after proper sling tensioning (RLPPs), with the aim to obtain the same pressure as after pneumoperitoneum induction. EUC recovery, defined as the use of no pad, was assessed 10 days, 30 days, and 6 months after catheter removal. RPS and proper autologous 6-branch sling positioning were feasible in all patients, without perioperative complications and negligible impact on overall operative time. Pneumoperitoneum induction increased, similarly, RLPP in all patients. An important decrease of sphincteric capability was evident after prostate removal and the following urethrovesical anastomosis, while proper sling tensioning allowed for restoration of sphincteric apparatus capability to its presurgical status (mean RLPPs 40.84 cmH2O vs RLPPp 40.39 cmH2O, p = 0.942). EUC recovery within 10 days after catheter removal was achieved in 59 (77%) patients and progressively improved over time. RPS, intraoperatively performed during RALP, allows for precise evaluation of the impact of the surgical procedure on sphincteric apparatus competence. Moreover, the use of the 6-branch suburethral sling, in association with RPS, allows for restoration of the proper supporting system to the urethral sphincter, similar to the

  5. Ares I-X Launch Abort System, Crew Module, and Upper Stage Simulator Vibroacoustic Flight Data Evaluation, Comparison to Predictions, and Recommendations for Adjustments to Prediction Methodology and Assumptions

    Science.gov (United States)

    Smith, Andrew; Harrison, Phil

    2010-01-01

    The National Aeronautics and Space Administration (NASA) Constellation Program (CxP) has identified a series of tests to provide insight into the design and development of the Crew Launch Vehicle (CLV) and Crew Exploration Vehicle (CEV). Ares I-X was selected as the first suborbital development flight test to help meet CxP objectives. The Ares I-X flight test vehicle (FTV) is an early operational model of CLV, with specific emphasis on CLV and ground operation characteristics necessary to meet Ares I-X flight test objectives. The in-flight part of the test includes a trajectory to simulate maximum dynamic pressure during flight and perform a stage separation of the Upper Stage Simulator (USS) from the First Stage (FS). The in-flight test also includes recovery of the FS. The random vibration response from the ARES 1-X flight will be reconstructed for a few specific locations that were instrumented with accelerometers. This recorded data will be helpful in validating and refining vibration prediction tools and methodology. Measured vibroacoustic environments associated with lift off and ascent phases of the Ares I-X mission will be compared with pre-flight vibration predictions. The measured flight data was given as time histories which will be converted into power spectral density plots for comparison with the maximum predicted environments. The maximum predicted environments are documented in the Vibroacoustics and Shock Environment Data Book, AI1-SYS-ACOv4.10 Vibration predictions made using statistical energy analysis (SEA) VAOne computer program will also be incorporated in the comparisons. Ascent and lift off measured acoustics will also be compared to predictions to assess whether any discrepancies between the predicted vibration levels and measured vibration levels are attributable to inaccurate acoustic predictions. These comparisons will also be helpful in assessing whether adjustments to prediction methodologies are needed to improve agreement between the

  6. Carcinomas epidermóides do pulmão na doença vibroacústica Respiratory squamous cell carcinomas in vibroacoustic disease

    Directory of Open Access Journals (Sweden)

    José Reis Ferreira

    2006-09-01

    de mutagénese em modelos animais e em trabalhadores expostos a RBF: a frequência de trocas de cromátides irmãs em pilotos de helicóptero está aumentada, bem como em modelos animais expostos a ruído e vibrações simultâneos, simulando o ambiente no cockpit de helicópteros.Background: In 1987, the autopsy of a vibroacoustic disease (VAD patient disclosed two tumours: a renal cell carcinoma and a malignant glioma in the brain. Since 1987, malignancy in VAD patients has been under close surveillance. To date, in a universe of 945 individuals, there are 46 cases of malignancies, of which 11 are multiple. Of the 11 cases of respiratory tract tumours, all were squamous cell carcinomas (SqCC. This report focuses on the morphological features of these tumours. Methods: Tumour fragments were collected (endoscopic biopsy or surgery from 11 male VAD patients (ave. age: 58±9 years, 3 non-smokers: 2 in glottis and 9 in the lung. In the 3 non-smokers, 2 had lung tumours and 1 had a glottis tumour. All were employed as or retired aircraft technicians, military or commercial pilots. Fragments were fixed either for light and electron microscopy. Immunohistochemistry studies used chromagranine and synaptophysine staining. Results: All lung tumours were located in the upper right lobe bronchi and were histologically poorly differentiated SqCC (Figs. 1, 2. The search with neuroendocrine markers was negative. The average age of tumour onset in helicopter pilots was below 50 years old while for the other professional groups it was above 50. Nine patients are deceased. The 2 surviving patients are heavy smokers (> 2 packs/day. Smoking habits had no i nfluence on tumour outcome and progression. Discussion: Epidemiological studies indicate that squamous cell carcinomas account for approximately 40% of all lung tumours in men. It seems to be highly relevant that all VAD patient respiratory tract tumours are squamous cell carcinomas. It is not surprising that helicopter pilots are

  7. Prediction of postoperative pain by preoperative pain response to heat stimulation in total knee arthroplasty

    DEFF Research Database (Denmark)

    Lunn, Troels H; Gaarn-Larsen, Lissi; Kehlet, Henrik

    2013-01-01

    : From 6-24hrs (primary), from postoperative day (POD) 1-7 (secondary), and from POD14-30 (tertiary). Two preoperative tonic heat stimuli with 47°C were used; short (5sec) and long (7min) stimulation upon which patients rated their pain response on an electronic VAS. Multivariate stepwise linear......It has been estimated that up to 54% of the variance in postoperative pain experience may be predicted with preoperative pain responses to experimental stimuli, with suprathreshold heat pain as the most consistent test modality. We aimed to explore if 2 heat test paradigms could predict...... and logistic regressions analyses were carried out including 8 potential preoperative explanatory variables (among these anxiety, depression, preoperative pain and pain catastrophizing) to assess pain response to preoperative heat pain stimulation as independent predictor for postoperative pain. 100 patients...

  8. Vagus Nerve Stimulation

    Science.gov (United States)

    Howland, Robert H.

    2014-01-01

    The vagus nerve is a major component of the autonomic nervous system, has an important role in the regulation of metabolic homeostasis, and plays a key role in the neuroendocrine-immune axis to maintain homeostasis through its afferent and efferent pathways. Vagus nerve stimulation (VNS) refers to any technique that stimulates the vagus nerve, including manual or electrical stimulation. Left cervical VNS is an approved therapy for refractory epilepsy and for treatment resistant depression. Right cervical VNS is effective for treating heart failure in preclinical studies and a phase II clinical trial. The effectiveness of various forms of non-invasive transcutaneous VNS for epilepsy, depression, primary headaches, and other conditions has not been investigated beyond small pilot studies. The relationship between depression, inflammation, metabolic syndrome, and heart disease might be mediated by the vagus nerve. VNS deserves further study for its potentially favorable effects on cardiovascular, cerebrovascular, metabolic, and other physiological biomarkers associated with depression morbidity and mortality. PMID:24834378

  9. The effects of electromyography-triggered electrical stimulation on shoulder subluxation, muscle activation, pain, and function in persons with stroke: A pilot study.

    Science.gov (United States)

    Jeon, Somyung; Kim, Young; Jung, Kyoungsim; Chung, Yijung

    2017-01-01

    The purpose of this study was to examine the effects of task-oriented electromyography-triggered stimulation for shoulder subluxation, muscle activation, pain and upper extremity function in hemiparetic stroke patients. Twenty participants with subacute hemiparetic stroke were recruited for this study and were randomly divided into two groups: experimental group (n = 10) and control group (n = 10). Subjects in the experimental group participated in task-oriented electromyography triggered stimulation for 30 minutes, five times a week for four weeks, whereas the control group received cyclic functional electrical stimulation for 30 minutes, five times a week for four weeks. Subjects in both groups received conventional physical therapy for four weeks (30 min/day, five times/week). Data collected included the degree of shoulder subluxation which had been confirmed by X-ray, muscle activation of the supraspinatus and posterior deltoid muscles by electromyography, pain by the Visual Analogue Scale (VAS), and hand function by the Fugl-Meyer Assessment (FMA) before and after the four week exercise period. The results showed significant improvement in shoulder subluxation, muscle activation, and VAS results in the experimental group, compared with the control group(p electromyography-triggered stimulation improved shoulder subluxation, muscle activation, pain and upper extremity function. These results suggest that task-oriented electromyography-triggered stimulation is effective and beneficial for individuals with subacute stroke, and that further studies should be conducted on multivarious anatomical regions.

  10. Canopy Water Content retrieval at different scales from empirical and physically-based remote sensing methods in the SMOS VAS cal/val site

    Science.gov (United States)

    Camacho de Coca, Fernando

    The SMOS (Soil Moisture and Ocean Salinity) space mission from the European Space Agency (ESA) is aimed to observe soil moisture over the continents and sea surface salinity over the oceans with enough resolution to be used in global climatic studies. Calibration and validation of SMOS products is an essential activity due to the exploratory nature of the mission. After launch, intense field activities will collect in situ information simultaneous to SMOS obser-vations in order to improve the empirical aspects of retrieval algorithms and to validate the products generated from these observations. One of the cal/val site selected over land is the Valencia Anchor station site (with an extended area for SMOS of 125 x 125 km2), where soil moisture will be measure intensively in 2010. In order to validate the SMOS soil moisture algorithms is necessary to characterize the water content in the vegetation canopy layer. This paper describes the retrieval of the canopy water content (CWC) in the Valencia Anchor station site at different scales using high-resolution satellite sensors and low resolution MODIS data. Two different approaches has been used: (??) an empirical approach has been used for mapping CWC over the VAS site during field campaigns, (??) artificial neural network has been trained with radiative transfer model simulations to analyze the performance of this approach for mapping CWC. 1. Two field campaigns were carried out to collect CWC at ground level in the study area over vineyards and irrigated crops. Measured CWC values for vineyard crops ranged between 0.05 and 0.2 kg/m2, and over irrigated crops CWC ranged between 0.1 and 1,5 kg/m2, which correspond with the full range of expected variations in the study area. An empirical relationship based on a multivariate ordinary least squares algorithm between the collected ground dataset and concomitant reflectance values coming from high resolution (HR) satellite sensors has been selected to produce CWC HR maps

  11. [Deep brain stimulation].

    Science.gov (United States)

    Fraix, V; Pollak, P; Chabardes, S; Ardouin, C; Koudsie, A; Benazzouz, A; Krack, P; Batir, A; Le Bas, J-F; Benabid, A-L

    2004-05-01

    The present renewal of the surgical treatment of Parkinson's disease, almost abandoned for twenty Years, arises from two main reasons. The first is the better understanding of the functional organization of the basal ganglia. It was demonstrated in animal models of Parkinson's disease that the loss of dopaminergic neurons within the substantia nigra, at the origin of the striatal dopaminergic defect, induces an overactivity of the excitatory glutamatergic subthalamo-internal pallidum pathway. The decrease in this hyperactivity might lead to an improvement in the pakinsonian symptoms. The second reason is the improvement in stereotactic neurosurgery in relation with the progress in neuroimaging techniques and with intraoperative electrophysiological microrecordings and stimulations, which help determine the location of the deep brain targets. In the 1970s chronic deep brain stimulation in humans was applied to the sensory nucleus of the thalamus for the treatment of intractable pain. In 1987, Benabid and colleagues suggested high frequency stimulation of the ventral intermediate nucleus of the thalamus in order to treat drug-resistant tremors and to avoid the adverse effects of thalamotomies. How deep brain stimulation works is not well known but it has been hypothetized that it could change the neuronal activities and thus avoid disease-related abnormal neuronal discharges. Potential candidates for deep brain stimulation are selected according to exclusion and inclusion criteria. Surgery can be applied to patients in good general and mental health, neither depressive nor demented and who are severely disabled despite all available drug therapies but still responsive to levodopa. The first session of surgery consists in the location of the target by ventriculography and/or brain MRI. The electrodes are implanted during the second session. The last session consists in the implantation of the neurostimulator. The ventral intermediate nucleus of the thalamus was the

  12. Experimental low-level jaw clenching inhibits temporal summation evoked by electrical stimulation in healthy human volunteers.

    Science.gov (United States)

    Tada, Hiroaki; Torisu, Tetsurou; Tanaka, Mihoko; Murata, Hiroshi; De Laat, Antoon; Svensson, Peter

    2015-05-01

    To examine the effect of low-level jaw clenching on temporal summation in healthy volunteers. In 18 healthy volunteers, the pain intensities evoked at the masseter muscle and the hand palm by the first and last stimuli in a train of repeated electrical stimuli (0.3 or 2.0 Hz) were rated using 0-100mm visual analogue scales (VAS), in order to evaluate temporal summation before and after three types of jaw-muscle tasks: low-level jaw clenching, repetitive gum chewing and mandibular rest position. A set of concentric surface electrodes with different diameters (small and large) was used for the electrical stimulation. The temporal summation evoked by the large diameter electrode with 2.0 Hz stimulation decreased significantly both on the masseter and the hand after low-level clenching (P ≤ 0.03), but did not show any significant change after the other tasks (P > 0.23). The VAS score of the first stimulation did not show any significant changes after low-level clenching (P > 0.57). Experimental low-level jaw clenching can inhibit pain sensitivity, especially temporal summation. Low-level jaw clenching can modify pain sensitivity, most likely through the central nervous system. The findings suggest that potential harmful low-level jaw clenching or tooth contacting could continue despite painful symptoms, e.g., temporomandibular disorders. Copyright © 2015 Elsevier Ltd. All rights reserved.

  13. Maturation of the human fetal startle response: evidence for sex-specific maturation of the human fetus.

    Science.gov (United States)

    Buss, Claudia; Davis, Elysia Poggi; Class, Quetzal A; Gierczak, Matt; Pattillo, Carol; Glynn, Laura M; Sandman, Curt A

    2009-10-01

    Despite the evidence for early fetal experience exerting programming influences on later neurological development and health risk, very few prospective studies of human fetal behavior have been reported. In a prospective longitudinal study, fetal nervous system maturation was serially assessed by monitoring fetal heart rate (FHR) responses to vibroacoustic stimulation (VAS) in 191 maternal/fetal dyads. Responses were not detected at 26 weeks gestational age (GA). Sex-specific, age-characteristic changes in the FHR response to VAS were observed by 31 weeks' GA. Males showed larger responses and continued to exhibit maturational changes until 37 weeks' GA, females however, presented with a mature FHR startle response by 31 weeks' GA. The results indicate that there are different rates of maturation in the male and female fetuses that may have implications for sex-specific programming influences.

  14. A double-blind randomized clinical trial on the efficacy of magnetic sacral root stimulation for the treatment of Monosymptomatic Nocturnal Enuresis.

    Science.gov (United States)

    Khedr, Eman M; Elbeh, Khaled A; Abdel Baky, Ahmed; Abo-Elfetoh, Noha; El-Hammady, Dina H; Korashy, Fatma

    2015-01-01

    Purpose of this study was to evaluate the long term efficacy of repetitive sacral root magnetic stimulation (rSMS) in patients with monosymptomatic nocturnal enuresis (MNE). Forty four patients were randomized to receive either sham or real repetitive sacral root magnetic stimulation (rSMS; 15 Hz with a total of 1500 pulses/session) for 10 sessions. Evaluation was performed before starting treatment, immediately after the 5th and 10th treatment session, and 1 month later, using frequency of enuresis/week, visual analogue scale (VAS) and quality of life as outcome measures. Resting and active motor thresholds of gastrocnemius muscles were measured before and after the end of sessions. Both treatment and control groups were comparable for baseline measures of frequency of enuresis, and VAS. The mean number of wet nights/week was significantly reduced in patients who received real rSMS. This improvement was maintained 1 month after the end of treatment. Patients receiving real-rSMS also reported an improvement in VAS ratings and quality of life. A significant reduction of resting motor threshold was recorded after rSMS in the real group while no such changes were observed in the sham group. These findings suggest that rSMS has potential as an adjuvant treatment for MNE and deserves further study.

  15. Ziconotide intrathecal delivery as treatment for secondary therapeutic failure of motor cortex stimulation after 6 years.

    Science.gov (United States)

    Voirin, J; Darie, I; Fischer, D; Simon, A; Rohmer-Heitz, I; Proust, F

    2016-10-01

    Motor cortex stimulation is a well-known treatment modality for refractory neuropathic pain. Nevertheless, some cases of therapeutic failure have been described but alternative therapies for these cases are rarely reported. The patient presented with neuropathic pain in his right arm due to a cervical syrinx which was surgically treated by a shunt in 2003 with no clinical improvement. As alternative therapy, after an evaluation by repetitive magnetic transcranial stimulation with significant benefit, motor cortex stimulation was successfully implanted in 2004. In 2010, a similar pain occurred in the same territory. Local mean pain visual analogical scale (VAS) increased to 82/100. A newer generation stimulation device was then implanted and, within a period of 8months, different stimulation parameter settings were tested, without any pain relief. An intrathecal drug delivery pump was then implanted in 2011, and the upper extremity catheter was located at the cervicothoracic junction. There was no postoperative complication. A bitherapy was initiated at a daily dosage of 0.2mg morphine and 1.3μg ziconotide, not modified since August 2013. At 43months follow-up, mean VAS was 21/100 with improvement of daily life and spare-time activities, anxiety and depression, quality of life (as measured by the SF-36 survey and EQ5D-3L questionnaire). Refractory neuropathic pain treated by motor cortex stimulation may be considered in palliative situations, and secondary therapeutic failure offers only a few perspectives. Intrathecal ziconotide, indicated as a first-line drug in non-cancer pain, could be proposed in such cases. Intrathecal drug delivery including ziconotide in refractory neuropathic pain represents a reasonable option with a good clinical tolerance. Copyright © 2016. Published by Elsevier Masson SAS.

  16. Copeptin under glucagon stimulation.

    Science.gov (United States)

    Lewandowski, Krzysztof C; Lewiński, Andrzej; Skowrońska-Jóźwiak, Elżbieta; Stasiak, Magdalena; Horzelski, Wojciech; Brabant, Georg

    2016-05-01

    Stimulation of growth hormone (GH) and adrenocorticotropic hormone (ACTH) secretion by glucagon is a standard procedure to assess pituitary dysfunction but the pathomechanism of glucagon action remains unclear. As arginine vasopressin (AVP) may act on the release of both, GH and ACTH, we tested here the role of AVP in GST by measuring a stable precursor fragment, copeptin, which is stoichiometrically secreted with AVP in a 1:1 ratio. ACTH, cortisol, GH, and copeptin were measured at 0, 60, 90, 120, 150, and 180 min during GST in 79 subjects: healthy controls (Group 1, n = 32), subjects with pituitary disease, but with adequate cortisol and GH responses during GST (Group 2, n = 29), and those with overt hypopituitarism (Group 3, n = 18). Copeptin concentrations significantly increased over baseline 150 and 180 min following glucagon stimulation in controls and patients with intact pituitary function but not in hypopituitarism. Copeptin concentrations were stimulated over time and the maximal increment correlated with ACTH, while correlations between copeptin and GH were weaker. Interestingly, copeptin as well as GH secretion was significantly attenuated when comparing subjects within the highest to those in the lowest BMI quartile (p Copeptin is significantly released following glucagon stimulation. As this release is BMI-dependent, the time-dependent relation between copeptin and GH may be obscured, whereas the close relation to ACTH suggests that AVP/copeptin release might be linked to the activation of the adrenal axis.

  17. Strategies for Stimulating Discussion

    Science.gov (United States)

    2017-06-01

    practices describe ways to facilitate communication during discussion. Use constructive questioning strategies . Facilitators serve to ensure the...lecture and group discussion teaching strategies in developing critical thinking skills. Communication Education, 45, 212-227. Gilmore, T. N., & Schall, E...U.S. Army Research Institute for the Behavioral and Social Sciences Research Report 2008 Strategies for Stimulating Discussion

  18. Stimulant Medication for ADHD

    OpenAIRE

    J Gordon Millichap

    1990-01-01

    The use of stimulant medication by primary care physicians in treatment of attention deficit hyperactivity disorder was evaluated by a random national survey of family practitioners and direct screening of 457 patients in midwestern cities and is reported from the Division of Developmental Disabilities, Departments of Pediatrics and Preventive Medicine University of Iowa, Iowa City and Department of Psychology, University of Kentucky, Lexington.

  19. Development Block or Stimulant

    DEFF Research Database (Denmark)

    Katznelson, Ron D; Howells, John

    subsequent to the courts upholding the validity of Edison's claim 2. We argue that Edison's patent had the effect of stimulating downstream invention. This analysis is contrary to several recent papers that have been published in the student-reviewed US law literature that assume Edison's patent was used...

  20. Transcranial brain stimulation: closing the loop between brain and stimulation.

    Science.gov (United States)

    Karabanov, Anke; Thielscher, Axel; Siebner, Hartwig Roman

    2016-08-01

    To discuss recent strategies for boosting the efficacy of noninvasive transcranial brain stimulation to improve human brain function. Recent research exposed substantial intra- and inter-individual variability in response to plasticity-inducing transcranial brain stimulation. Trait-related and state-related determinants contribute to this variability, challenging the standard approach to apply stimulation in a rigid, one-size-fits-all fashion. Several strategies have been identified to reduce variability and maximize the plasticity-inducing effects of noninvasive transcranial brain stimulation. Priming interventions or paired associative stimulation can be used to 'standardize' the brain-state and hereby, homogenize the group response to stimulation. Neuroanatomical and neurochemical profiling based on magnetic resonance imaging and spectroscopy can capture trait-related and state-related variability. Fluctuations in brain-states can be traced online with functional brain imaging and inform the timing or other settings of transcranial brain stimulation. State-informed open-loop stimulation is aligned to the expression of a predefined brain state, according to prespecified rules. In contrast, adaptive closed-loop stimulation dynamically adjusts stimulation settings based on the occurrence of stimulation-induced state changes. Approaches that take into account trait-related and state-related determinants of stimulation-induced plasticity bear considerable potential to establish noninvasive transcranial brain stimulation as interventional therapeutic tool.

  1. Effect of stimulation in coma.

    Science.gov (United States)

    Karma, Deepa; Rawat, A K

    2006-10-01

    To find out efficacy and benefits of early starting of stimulation therapy in coma patients. Randomized controlled trial. Sixty children admitted to the Department of Pediatrics, having coma due to non-traumatic neurological insult were randomly selected. Both study and control groups had 30 patients each. Children in the study group were given stimulation therapy while those in control group received no stimulation. The level of consciousness was assessed before and two weeks after giving stimulation therapy. Improvement in level of consciousness was better in study group as compared to control after two weeks of stimulation therapy. Stimulation therapy was found to be highly effective in coma patients.

  2. Transcranial brain stimulation: closing the loop between brain and stimulation

    DEFF Research Database (Denmark)

    Karabanov, Anke; Thielscher, Axel; Siebner, Hartwig Roman

    2016-01-01

    stimulation. Trait-related and state-related determinants contribute to this variability, challenging the standard approach to apply stimulation in a rigid, one-size-fits-all fashion. Several strategies have been identified to reduce variability and maximize the plasticity-inducing effects of noninvasive......-related and state-related variability. Fluctuations in brain-states can be traced online with functional brain imaging and inform the timing or other settings of transcranial brain stimulation. State-informed open-loop stimulation is aligned to the expression of a predefined brain state, according to prespecified...... rules. In contrast, adaptive closed-loop stimulation dynamically adjusts stimulation settings based on the occurrence of stimulation-induced state changes. SUMMARY: Approaches that take into account trait-related and state-related determinants of stimulation-induced plasticity bear considerable...

  3. Stimulated Black Hole Evaporation

    CERN Document Server

    Spaans, Marco

    2016-01-01

    Black holes are extreme expressions of gravity. Their existence is predicted by Einstein's theory of general relativity and is supported by observations. Black holes obey quantum mechanics and evaporate spontaneously. Here it is shown that a mass rate $R_f\\sim 3\\times 10^{-8} (M_0/M)^{1/2}$ $M_0$ yr$^{-1}$ onto the horizon of a black hole with mass $M$ (in units of solar mass $M_0$) stimulates a black hole into rapid evaporation. Specifically, $\\sim 3 M_0$ black holes can emit a large fraction of their mass, and explode, in $M/R_f \\sim 3\\times 10^7 (M/M_0)^{3/2}$ yr. These stimulated black holes radiate a spectral line power $P \\sim 2\\times 10^{39} (M_0/M)^{1/2}$ erg s$^{-1}$, at a wavelength $\\lambda \\sim 3\\times 10^5 (M/M_0)$ cm. This prediction can be observationally verified.

  4. Raft River well stimulation experiments: geothermal reservoir well stimulation program

    Energy Technology Data Exchange (ETDEWEB)

    1980-08-01

    The Geothermal Reservoir Well Stimulation Program (GRWSP) performed two field experiments at the Raft River KGRA in 1979. Wells RRGP-4 and RRGP-5 were selected for the hydraulic fracture stimulation treatments. The well selection process, fracture treatment design, field execution, stimulation results, and pre- and post-job evaluations are presented.

  5. Dorsal column stimulator applications

    OpenAIRE

    Yampolsky, Claudio; Hem, Santiago; Bendersky, Damián

    2012-01-01

    Background: Spinal cord stimulation (SCS) has been used to treat neuropathic pain since 1967. Following that, technological progress, among other advances, helped SCS become an effective tool to reduce pain. Methods: This article is a non-systematic review of the mechanism of action, indications, results, programming parameters, complications, and cost-effectiveness of SCS. Results: In spite of the existence of several studies that try to prove the mechanism of action of SCS, it still remains...

  6. Metabolic and clinical assessment of efficacy of cryoablation therapy on skeletal masses by {sup 18}F-FDG positron emission tomography/computed tomography (PET/CT) and visual analogue scale (VAS): initial experience

    Energy Technology Data Exchange (ETDEWEB)

    Masala, Salvatore; Bartolucci, Alberto D.; Mammucari, Matteo; Simonetti, Giovanni [University Hospital Tor Vergata, Department of Diagnostic and Molecular Imaging, Interventional Radiology and Radiotherapy, Rome (Italy); Schillaci, Orazio; Calabria, Ferdinando [University Hospital Tor Vergata, Department of Diagnostic and Molecular Imaging, Interventional Radiology and Radiotherapy, Rome (Italy); I.R.C.C.S. Neuromed, Department of Nuclear Medicine and Neuroradiology, Pozzilli (Italy); Policlinico Tor Vegata, Department of Diagnostic and Molecular Imaging, Interventional Radiology and Radiotherapy, Rome (Italy)

    2011-02-15

    Various therapy modalities have been proposed as standard treatments in management of bone metastases. Radiation therapy remains the standard of care for patients with localized bone pain, but up to 30% of them do not experience notable pain relief. Percutaneous cryoablation is a minimally invasive technique that induces necrosis by alternately freezing and thawing a target tissue. This technique is successfully used to treat a variety of malignant and benign diseases in different sites. {sup 18}F-FDG positron emission tomography/computed tomography ({sup 18}F-FDG PET/CT) is a single technique of imaging that provides in a ''single step'' both morphological and metabolic features of neoplastic lesions of the bone. The aim of this study was to evaluate the efficacy of the cryosurgical technique on secondary musculoskeletal masses according to semi-quantitative PET analysis and clinical-test evaluation with the visual analogue scale (VAS). We enrolled 20 patients with painful bone lesions (score pain that exceeded 4 on the VAS) that were non-responsive to treatment; one lesion per patient was treated. All patients underwent a PET-CT evaluation before and 8 weeks after cryotherapy; maximum standardized uptake value (SUV{sub max}) was measured before and after treatment for metabolic assessment of response to therapy. After treatment, 18 patients (90%) showed considerable reduction in SUV{sub max} value (>50%) suggestive of response to treatment; only 2 patients did not show meaningful reduction in metabolic activity. Our preliminary study demonstrates that quantitative analysis provided by PET correlates with response to cryoablation therapy as assessed by CT data and clinical VAS evaluation. (orig.)

  7. Treatment of Idiopathic Chronic Orchialgia with Transcutaneous Electrical Nerve Stimulation (TENS:A Preliminary Result

    Directory of Open Access Journals (Sweden)

    Ekrem Akdeniz

    2016-01-01

    Full Text Available Purpose: Unilateral or bilateral testicular pain lasting more than 3 months is called as chronic orchialgia. Aproximately 25-50% of chronic orchialgia is idiopatic origin. This study aimed the effectiveness of Transcutaneous Electrical Nerve Stimulation (TENS therapy due to Idiopathic Chronic Orchialgia (ICO. Methods: Five patients were included into this study with ICO that diagnosed with physical examination, urine analyses, urinary system x-ray film, and scrotal doppler ultrasound. Medical history revealed that multiple conservative therapy attempts failed to alleviate the pain. Two of the patients had right sided ICO. Traditional TENS device is placed to the most painful points. TENS applied 3 times in a week with duration 30 minutes for 4 weeks. Before and after TENS application, patients were evaluated by using Visual Analog Scale (VAS at first and third months. Results: Median age of patients was 26.20±2.38 (22-30. Mean VAS value was 6.52 ± 0.89 before the procedure. After 1 month VAS value was 3.82 ± 0.83 (p0.05. None of the patients needed any analgesics after during the one month. No complications, hyperemia or hypoesthesia of the scrotal or penile skin, occurred after the procedure. Conclusion: TENS reduces pain by increasing endorphin release in the spinal cord dorsal horn. TENS is very effective method for first 1 month in patients with ICO but its effect reduces by the time. There is no standard therapeutic protocol for idiopathic chronic orchialgia. Therefore TENS may be an alternative for patients who do not benefit from medical therapy and do not want invasive procedures. Short-term use of TENS and low number of the patients are the limitations of this study. Randomized, placebo-controlled, and longer follow-up period studies are needed to better assess the efficacy of TENS for ICO.

  8. The Effect of Uni- and Bilateral Thalamic Deep Brain Stimulation on Speech in Patients With Essential Tremor: Acoustics and Intelligibility.

    Science.gov (United States)

    Becker, Johannes; Barbe, Michael T; Hartinger, Mariam; Dembek, Till A; Pochmann, Jil; Wirths, Jochen; Allert, Niels; Mücke, Doris; Hermes, Anne; Meister, Ingo G; Visser-Vandewalle, Veerle; Grice, Martine; Timmermann, Lars

    2017-04-01

    Deep brain stimulation (DBS) of the ventral intermediate nucleus (VIM) is performed to suppress medically-resistant essential tremor (ET). However, stimulation induced dysarthria (SID) is a common side effect, limiting the extent to which tremor can be suppressed. To date, the exact pathogenesis of SID in VIM-DBS treated ET patients is unknown. We investigate the effect of inactivated, uni- and bilateral VIM-DBS on speech production in patients with ET. We employ acoustic measures, tempo, and intelligibility ratings and patient's self-estimated speech to quantify SID, with a focus on comparing bilateral to unilateral stimulation effects and the effect of electrode position on speech. Sixteen German ET patients participated in this study. Each patient was acoustically recorded with DBS-off, unilateral-right-hemispheric-DBS-on, unilateral-left-hemispheric-DBS-on, and bilateral-DBS-on during an oral diadochokinesis task and a read German standard text. To capture the extent of speech impairment, we measured syllable duration and intensity ratio during the DDK task. Naïve listeners rated speech tempo and speech intelligibility of the read text on a 5-point-scale. Patients had to rate their "ability to speak". We found an effect of bilateral compared to unilateral and inactivated stimulation on syllable durations and intensity ratio, as well as on external intelligibility ratings and patients' VAS scores. Additionally, VAS scores are associated with more laterally located active contacts. For speech ratings, we found an effect of syllable duration such that tempo and intelligibility was rated worse for speakers exhibiting greater syllable durations. Our data confirms that SID is more pronounced under bilateral compared to unilateral stimulation. Laterally located electrodes are associated with more severe SID according to patient's self-ratings. We can confirm the relation between diadochokinetic rate and SID in that listener's tempo and intelligibility ratings can be

  9. Does a single session of theta-burst transcranial magnetic stimulation of inferior temporal cortex affect tinnitus perception?

    Directory of Open Access Journals (Sweden)

    Moser Tobias

    2009-05-01

    Full Text Available Abstract Background Cortical excitability changes as well as imbalances in excitatory and inhibitory circuits play a distinct pathophysiological role in chronic tinnitus. Repetitive transcranial magnetic stimulation (rTMS over the temporoparietal cortex was recently introduced to modulate tinnitus perception. In the current study, the effect of theta-burst stimulation (TBS, a novel rTMS paradigm was investigated in chronic tinnitus. Twenty patients with chronic tinnitus completed the study. Tinnitus severity and loudness were monitored using a tinnitus questionnaire (TQ and a visual analogue scale (VAS before each session. Patients received 600 pulses of continuous TBS (cTBS, intermittent TBS (iTBS and intermediate TBS (imTBS over left inferior temporal cortex with an intensity of 80% of the individual active or resting motor threshold. Changes in subjective tinnitus perception were measured with a numerical rating scale (NRS. Results TBS applied to inferior temporal cortex appeared to be safe. Although half of the patients reported a slight attenuation of tinnitus perception, group analysis resulted in no significant difference when comparing the three specific types of TBS. Converting the NRS into the VAS allowed us to compare the time-course of aftereffects. Only cTBS resulted in a significant short-lasting improvement of the symptoms. In addition there was no significant difference when comparing the responder and non-responder groups regarding their anamnestic and audiological data. The TQ score correlated significantly with the VAS, lower loudness indicating less tinnitus distress. Conclusion TBS does not offer a promising outcome for patients with tinnitus in the presented study.

  10. Injection of Mesenchymal Stem Cells as a Supplementary Strategy of Marrow Stimulation Improves Cartilage Regeneration After Lateral Sliding Calcaneal Osteotomy for Varus Ankle Osteoarthritis: Clinical and Second-Look Arthroscopic Results.

    Science.gov (United States)

    Kim, Yong Sang; Koh, Yong Gon

    2016-05-01

    To compare the clinical and second-look arthroscopic outcomes in patients undergoing arthroscopic marrow stimulation combined with lateral sliding calcaneal osteotomy for varus ankle osteoarthritis, with or without adipose-derived mesenchymal stem cell (MSC) injection. In this retrospective comparative study, 49 patients with varus ankle osteoarthritis underwent second-look arthroscopy after arthroscopic marrow stimulation combined with lateral sliding calcaneal osteotomy between January 2010 and November 2012; 23 ankles underwent marrow stimulation alone (group 1), and 26 underwent marrow stimulation with MSC injection (group 2). The decision whether to receive the MSC injection, which was free of charge, was solely up to the patients. Second-look arthroscopies were performed at a mean of 12.5 months and 12.4 months postoperatively in group 1 and group 2, respectively. Clinical outcome measures included a visual analog scale (VAS) score for pain and the American Orthopaedic Foot & Ankle Society (AOFAS) score. The radiologic outcome variable was the talar tilt angle. On second-look arthroscopy, cartilage regeneration was evaluated using the International Cartilage Repair Society (ICRS) grade. The mean VAS score improved significantly from 7.3 ± 0.9 to 3.9 ± 1.2 in group 1 and from 7.4 ± 0.8 to 3.1 ± 1.5 in group 2 at final follow-up (P osteoarthritis who underwent lateral sliding calcaneal osteotomy, significant improvements in VAS and AOFAS scores, as well as better ICRS grades, were achieved at short-term follow-up after marrow stimulation with additional MSC injection compared with after marrow stimulation alone. Level III, retrospective comparative study. Copyright © 2016 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.

  11. Spinal Cord Stimulation

    DEFF Research Database (Denmark)

    Meier, Kaare

    2014-01-01

    Spinal cord stimulation (SCS) is a surgical treatment for chronic neuropathic pain that is refractory to other treatment. Originally described by Shealy et al. in 1967(1), it is used to treat a range of conditions such as complex regional pain syndrome (CRPS I)(2), angina pectoris(3), radicular...... pain after failed back surgery syndrome (FBSS)(4), pain due to peripheral nerve injury, stump pain(5), peripheral vascular disease(6) and diabetic neuropathy(7,8); whereas phantom pain(9), postherpetic neuralgia(10), chronic visceral pain(11), and pain after partial spinal cord injury(12) remain more...

  12. Neuromuscular electrical stimulation training: a safe and effective treatment for facioscapulohumeral muscular dystrophy patients.

    Science.gov (United States)

    Colson, Serge S; Benchortane, Michaël; Tanant, Véronique; Faghan, Jean-Paul; Fournier-Mehouas, Manuela; Benaïm, Charles; Desnuelle, Claude; Sacconi, Sabrina

    2010-05-01

    To investigate the feasibility, safety, and effectiveness of neuromuscular electrical stimulation (NMES) strength training in facioscapulohumeral muscular dystrophy (FSHD) patients. Uncontrolled before-after trial. Neuromuscular disease center in a university hospital and a private-practice physical therapy office. FSHD patients (N=9; 3 women, 6 men; age 55.2+/-10.4y) clinically characterized by shoulder girdle and quadriceps femoris muscle weakness. Patients underwent 5 months of strength training with NMES bilaterally applied to the deltoideus, trapezius transversalis, vastus lateralis, and vastus medialis muscles for five 20-minute sessions per week. Plasma creatine kinase (CK) activity; scores for pain and fatigue on visual analog scales (VAS), manual muscle testing (MMT), maximal voluntary isometric contraction (MVIC), 6-minute walking tests (6MWT), and self-reported changes in daily living activities. NMES strength training was well tolerated (CK activity and pain and fatigue scores on VAS were not modified). Most of the muscle functions (shoulder flexion and extension and knee extension) assessed by MMT were significantly increased. MVIC of shoulder flexion and abduction and the 6MWT distance were also improved. In FSHD, NMES strength training appears to be safe with positive effects on muscle function, strength, and capacity for daily activities.

  13. Zīmola vērtība no patērētāju perspektīvas sporta apģerbu un apavu tirgū.

    OpenAIRE

    Kadakovska, Agnese

    2017-01-01

    Bakalaura darba tēma ir “Zīmola vērtība no patērētāju perspektīvas sporta apģērbu un apavu tirgū”. Bakalaura darba mērķis ir pamatojoties uz izpētīto teorētisko informāciju par zīmola vērtības no patērētāju perspektīvas veidošanu, identificēt patērētāju skatījumā vērtīgākos sporta apģērbu un apavu tirgus zīmolus Latvijā un izstrādāt priekšlikumus to vērtības palielināšanai. Bakalaura darbs sastāv no ievada, 3 nodaļām, secinājumiem un priekšlikumiem, izmantotās literatūras saraksta un pielikum...

  14. Recording of corticospinal evoked potential for optimum placement of motor cortex stimulation electrodes in the treatment of post-stroke pain.

    Science.gov (United States)

    Yamamoto, Takamitsu; Katayama, Yoichi; Obuchi, Toshiki; Kano, Toshikazu; Kobayashi, Kazutaka; Oshima, Hideki; Fukaya, Chikashi; Kakigi, Ryusuke

    2007-09-01

    The corticospinal motor evoked potential (MEP) evoked by motor cortex stimulation was investigated as an intraoperative index for the placement of stimulation electrodes in the epidural space over the motor cortex for the treatment of post-stroke pain. A grid of plate electrodes was placed in the epidural space to cover the motor cortex, sensory cortex, and premotor cortex employing a magnetic resonance imaging-guided neuronavigation system in two patients with severe post-stroke pain in the right extremities, a 66-year-old man with dysesthesia manifesting as burning and aching sensation, and a 67-year-old woman with dysesthesia manifesting as pricking sensation. The D-wave of the corticospinal MEP was recorded with a flexible wire electrode placed in the epidural space of the spinal cord during anodal monopolar stimulation of each plate electrode under general anesthesia. The grid electrode was fixed in position with dural sutures and the craniotomy closed. The effect of pain reduction induced by anodal monopolar stimulation of the same plate electrodes was examined using the visual analogue scale (VAS) on a separate day in the awake state without anesthesia. Comparison of the percentage VAS reduction and the recorded amplitude of the D-wave employing the same stimulation electrode revealed significant correlations in Case 1 (r = 0.828, p r = 0.807, p < 0.01). The grid electrode was then replaced with two RESUME electrodes over the hand and foot areas, and the optimum positions were identified by D-wave recording before electrode fixation. Both patients reported satisfactory pain alleviation with lower stimulation voltages than usually required for patients with similar symptoms. These results indicate the potential of D-wave recording as an intraoperative indicator for the placement of stimulating electrodes over the motor cortex for pain relief.

  15. [Early stimulation > programs evaluation].

    Science.gov (United States)

    Bonnier, C

    2007-09-01

    Early intervention include educational and neuroprotection strategies. Early educational strategies are based on the cerebral plasticity concept. Neuroprotection, initially reserved for molecules preventing cell death phenomena, can be extended now to all actions promoting harmonious development and preventing handicaps, and include organisational, therapeutic and environmental aspects. Early stimulation programs have been first devised in United States for vulnerable children who belong to an unfavorable socio-economic category ; positive effects were recorded in school failure rates and social problems ; programs have also been launched in several countries for premature infants and infants with a low birth weight, population exposed to a high risk of deficiencies. The programs are targetted either to the child, or to the parents, or combined to provide assistance for both the child and the parents. The programs given the best evaluation are NIDCAP Program in Sweden (Newborn Individualized Developmental Care and Assessment Program), intended for babies neonatal intensive care units, then a longitudinal, multisite program, known as IHDP (Infant Health and Development Program). It was launched in United States for infants stimulation is maintained and when mothers have a low level of education.

  16. Efficacy of Sensory Transcutaneous Electrical Nerve Stimulation on Perceived Pain and Gait Patterns in Individuals With Experimental Knee Pain.

    Science.gov (United States)

    Son, S Jun; Kim, Hyunsoo; Seeley, Matthew K; Hopkins, J Ty

    2017-01-01

    To examine the effect of experimental knee pain on perceived knee pain and gait patterns and to examine the efficacy of transcutaneous electrical nerve stimulation (TENS) on perceived knee pain and pain-induced knee gait mechanics. Crossover trial. Biomechanics laboratory. Recreationally active, individuals without musculoskeletal pain aged 18 to 35 years (N=30). Thirty able-bodied individuals were assigned to either a TENS (n=15) or a placebo (n=15) group. All participants completed 3 experimental sessions in a counterbalanced order separated by 2 days: (1) hypertonic saline infusion (5% NaCl); (2) isotonic saline infusion (0.9% NaCl); and (3) control. Each group received sensory electrical stimulation or placebo treatment for 20 minutes, respectively. Perceived pain was collected every 2 minutes using a 10-cm visual analog scale (VAS) for 50 minutes and analyzed using a mixed model analysis of covariance with repeated measures. Gait analyses were performed at baseline, infusion, and treatment. Sagittal and frontal knee angles and internal net joint torque across the entire stance were analyzed using a functional data analysis approach. Hypertonic saline infusion increased perceived pain (4/10cm on a VAS; Pgait abnormalities as compared with placebo treatment (Pgait patterns in a way that indicates potential quadriceps weakness. However, TENS treatment effectively reduces perceived pain and restores pain-induced gait abnormalities in sagittal knee mechanics. Copyright © 2016 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

  17. Transcranial brain stimulation: closing the loop between brain and stimulation

    DEFF Research Database (Denmark)

    Karabanov, Anke; Thielscher, Axel; Siebner, Hartwig Roman

    2016-01-01

    PURPOSE OF REVIEW: To discuss recent strategies for boosting the efficacy of noninvasive transcranial brain stimulation to improve human brain function. RECENT FINDINGS: Recent research exposed substantial intra- and inter-individual variability in response to plasticity-inducing transcranial brain...... transcranial brain stimulation. Priming interventions or paired associative stimulation can be used to ‘standardize’ the brain-state and hereby, homogenize the group response to stimulation. Neuroanatomical and neurochemical profiling based on magnetic resonance imaging and spectroscopy can capture trait......-related and state-related variability. Fluctuations in brain-states can be traced online with functional brain imaging and inform the timing or other settings of transcranial brain stimulation. State-informed open-loop stimulation is aligned to the expression of a predefined brain state, according to prespecified...

  18. Efficacy of traditional Japanese herbal medicines-Keishikajutsubuto (TJ-18) and Bushi-matsu (TJ-3022)-against postherpetic neuralgia aggravated by self-reported cold stimulation: a case series.

    Science.gov (United States)

    Nakanishi, Miho; Arimitsu, Junsuke; Kageyama, Mitsuru; Otsuka, Shizue; Inoue, Takaya; Nishida, Shinji; Yoshikawa, Hideki; Kishida, Yuki

    2012-07-01

    It has been reported that postherpetic neuralgia (PHN) in patients over 60 years of age is aggravated under cold stimulation and is often difficult to treat. Keishikajutsubuto (TJ-18) and Bushi-matsu (TJ-3022) are traditional Japanese herbal medicines and have long been used to treat neuralgia and arthralgia, which are aggravated following cold stimulation. This study was designed to evaluate the effectiveness of combined TJ-18 and TJ-3022 therapy in cases of PHN aggravated by self-reported cold stimulation. Fifteen (15) PHN patients aged 60 years and over were examined. Patients were aware of the persistent pain despite other treatments; pain was generally aggravated following exposure to cold stimulation. First, TJ-18 (7.5 g/day) was administered to patients, and then TJ-3022 (1.0 g/day) was also administered and progressively increased by 0.5-1.0 g increments every 2-4 weeks, until stable improvement was achieved, which was rated using the visual analogue scale (VAS). Analgesic effects were evaluated using the VAS during each patient visit. Background variables, responses to treatment (time course of VAS rating, VAS improvement rate), the amount of additional TJ-3022 administered, and adverse reactions were analyzed. Twelve (12) of the 15 patients completed the entire trial. Patient ages were 61-85 years, the male-to-female ratio was 4:8, and length of time after onset of herpes zoster was 2-92 months. In 3 patients, oral TJ-18 treatment was not possible due to hot flash or gastric discomfort. The VAS improvement rate for patients being orally administered both TJ-18 and TJ-3022 was 76.5±27.7% (mean±standard deviation). The additional TJ-3022 dose was 1.0-5.0 g/day. Twelve (12) patients have been treated without serious adverse reactions. TJ-18 and TJ-3022 combination treatment is a promising means of treating intractable PHN, which has a self-reported tendency to aggravate pain under cold stimulation.

  19. [Apparatus "Stimul-1" foe electric stimulation of muscles].

    Science.gov (United States)

    Andrianova, G G; Prokopenko, G I; Shabashevich, L B; Khvostov, L N

    1977-01-01

    The apparatus "Stimul-1" has been designed and recommended for batch production, its purpose being broad application in the medical practice of electrical stimulation of the muscles. For stimulation is used sinusoidal a.c. current with frequency of 2 kHz, which produces and effective contraction of the muscles without causing any sensation of pain. The unit is constructed by using up-to-date components, including microminiature logic circuits, operational amplifiers and field-effect transistors.

  20. Transcranial brain stimulation: closing the loop between brain and stimulation

    OpenAIRE

    Karabanov, Anke; Thielscher, Axel; Siebner, Hartwig Roman

    2016-01-01

    Purpose of review To discuss recent strategies for boosting the efficacy of noninvasive transcranial brain stimulation to improve human brain function. Recent findings Recent research exposed substantial intra- and inter-individual variability in response to plasticity-inducing transcranial brain stimulation. Trait-related and state-related determinants contribute to this variability, challenging the standard approach to apply stimulation in a rigid, one-size-fits-all fashion. Several strateg...

  1. Transcutaneous electrical nerve stimulation therapy in reduction of orofacial pain

    Directory of Open Access Journals (Sweden)

    Đorđević Igor

    2014-01-01

    Full Text Available Introduction. Patients with craniomandibular disorders suffer from hypertonic, fatigued and painful masticatory muscles. This condition can lead to limitation of mandibular jaw movements. All of these symptoms and signs are included in myofascial pain dysfunction syndrome. Transcutaneous electrical nerve stimulation (TENS has been used for treatment of these patients. Objective. The aim of this study was to assess the effect of TENS therapy on chronic pain reduction in patients with the muscular dysfunction symptom. Methods. In order to evaluate the effect of TENS therapy before and after the treatment, Craniomandibular Index (Helkimo was used. Pain intensity was measured by VAS. Patients had TENS treatment over two-week period. BURST TENS modality was used. Current intensity was individually adjusted. Results. Two patients did not respond to TENS therapy. Complete pain reduction was recorded in 8 patients, while pain reduction was not significantly different after TENS therapy in 10 patients. Conclusion. TENS therapy was confirmed as therapeutic procedure in orofacial muscle relaxation and pain reduction.

  2. Vagus Nerve Stimulation.

    Science.gov (United States)

    Ekmekçi, Hakan; Kaptan, Hülagu

    2017-06-15

    The vagus nerve stimulation (VNS) is an approach mainly used in cases of intractable epilepsy despite all the efforts. Also, its benefits have been shown in severe cases of depression resistant to typical treatment. The aim of this study was to present current knowledge of vagus nerve stimulation. A new value has emerged just at this stage: VNS aiming the ideal treatment with new hopes. It is based on the placement of a programmable generator on the chest wall. Electric signals from the generator are transmitted to the left vagus nerve through the connection cable. Control on the cerebral bioelectrical activity can be achieved by way of these signal sent from there in an effort for controlling the epileptic discharges. The rate of satisfactory and permanent treatment in epilepsy with monotherapy is around 50%. This rate will increase by one-quarters (25%) with polytherapy. However, there is a patient group roughly constituting one-thirds of this population, and this group remains unresponsive or refractory to all the therapies and combined regimes. The more the number of drugs used, the more chaos and side effects are observed. The anti-epileptic drugs (AEDs) used will have side effects on both the brain and the systemic organs. Cerebral resection surgery can be required in some patients. The most commonly encountered epilepsy type is the partial one, and the possibility of benefiting from invasive procedures is limited in most patients of this type. Selective amygdala-hippocampus surgery is a rising value in complex partial seizures. Therefore, as epilepsy surgery can be performed in very limited numbers and rather developed centres, success can also be achieved in limited numbers of patients. The common ground for all the surgical procedures is the target of preservation of memory, learning, speaking, temper and executive functions as well as obtaining a good control on seizures. However, the action mechanism of VNS is still not exactly known. On the other hand

  3. Engagement sensitive visual stimulation

    Directory of Open Access Journals (Sweden)

    Deepesh Kumar

    2016-06-01

    Full Text Available Stroke is one of leading cause of death and disability worldwide. Early detection during golden hour and treatment of individual neurological dysfunction in stroke using easy-to-access biomarkers based on a simple-to-use, cost-effective, clinically-valid screening tool can bring a paradigm shift in healthcare, both urban and rural. In our research we have designed a quantitative automatic home-based oculomotor assessment tool that can play an important complementary role in prognosis of neurological disorders like stroke for the neurologist. Once the patient has been screened for stroke, the next step is to design proper rehabilitation platform to alleviate the disability. In addition to the screening platform, in our research, we work in designing virtual reality based rehabilitation exercise platform that has the potential to deliver visual stimulation and in turn contribute to improving one’s performance.

  4. Collective stimulated Brillouin scatter

    CERN Document Server

    Korotkevich, Alexander O; Rose, Harvey A

    2011-01-01

    We develop a statistical theory of stimulated Brillouin backscatter (BSBS) of a spatially and temporally partially incoherent laser beam for laser fusion relevant plasma. We find a new collective regime of BSBS which has a much larger threshold than the classical threshold of a coherent beam in long-scale-length laser fusion plasma. We identify two contributions to BSBS convective instability increment. The first is collective with intensity threshold independent of the laser correlation time and controlled by diffraction. The second is independent of diffraction, it grows with increase of the correlation time and does not have an intensity threshold. The instability threshold is inside the typical parameter region of National Ignition Facility (NIF). We also find that the bandwidth of KrF-laser-based fusion systems would be large enough to allow additional suppression of BSBS.

  5. Collective stimulated Brillouin backscatter

    CERN Document Server

    Lushnikov, Pavel M

    2007-01-01

    We develop the statistical theory of the stimulated Brillouin backscatter (BSBS) instability of a spatially and temporally partially incoherent laser beam for laser fusion relevant plasma. We find a new regime of BSBS which has a much larger threshold than the classical threshold of a coherent beam in long-scale-length laser fusion plasma. Instability is collective because it does not depend on the dynamics of isolated speckles of laser intensity, but rather depends on averaged beam intensity. We identify convective and absolute instability regimes. Well above the incoherent threshold the coherent instability growth rate is recovered. The threshold of convective instability is inside the typical parameter region of National Ignition Facility (NIF) designs although current NIF bandwidth is not large enough to insure dominance of collective instability and suggests lower instability threshold due to speckle contribution. In contrast, we estimate that the bandwidth of KrF-laser-based fusion systems would be larg...

  6. Stimulated coherent transition radiation

    Energy Technology Data Exchange (ETDEWEB)

    Hung-chi Lihn

    1996-03-01

    Coherent radiation emitted from a relativistic electron bunch consists of wavelengths longer than or comparable to the bunch length. The intensity of this radiation out-numbers that of its incoherent counterpart, which extends to wavelengths shorter than the bunch length, by a factor equal to the number of electrons in the bunch. In typical accelerators, this factor is about 8 to 11 orders of magnitude. The spectrum of the coherent radiation is determined by the Fourier transform of the electron bunch distribution and, therefore, contains information of the bunch distribution. Coherent transition radiation emitted from subpicosecond electron bunches at the Stanford SUNSHINE facility is observed in the far-infrared regime through a room-temperature pyroelectric bolometer and characterized through the electron bunch-length study. To measure the bunch length, a new frequency-resolved subpicosecond bunch-length measuring system is developed. This system uses a far-infrared Michelson interferometer to measure the spectrum of coherent transition radiation through optical autocorrelation with resolution far better than existing time-resolved methods. Hence, the radiation spectrum and the bunch length are deduced from the autocorrelation measurement. To study the stimulation of coherent transition radiation, a special cavity named BRAICER is invented. Far-infrared light pulses of coherent transition radiation emitted from electron bunches are delayed and circulated in the cavity to coincide with subsequent incoming electron bunches. This coincidence of light pulses with electron bunches enables the light to do work on electrons, and thus stimulates more radiated energy. The possibilities of extending the bunch-length measuring system to measure the three-dimensional bunch distribution and making the BRAICER cavity a broadband, high-intensity, coherent, far-infrared light source are also discussed.

  7. Symptomatic response to blocked and unblocked pentagastrin stimulation in functional dyspepsia - Comparison of responders and non-responders to omeprazole identified in a single-subject trial model

    DEFF Research Database (Denmark)

    Madsen, L.G.; Bytzer, P.

    2008-01-01

    Background: The role of acid in functional dyspepsia is controversial and drug treatment trials indicate that only a subset of patients has acid-related symptoms. A novel single-subject trial design, the Random Starting Day trial (RSD trial), was developed to identify acid-related symptoms. We...... was expected not to be influenced by gastric acid stimulation or type of treatment. Methods: Nineteen patients were evaluated. Symptomatic response to pentagastrin (6 mu g/kg) was assessed twice in each patient following placebo and omeprazole (40 mg bid) treatment in a randomized, double-blind, cross......-over design. Epigastric pain was assessed every 15 for 90 min after stimulation using a 5-graded Likert scale and a VAS scale. A positive acid provocation test was defined as an increase of the Likert score of epigastric pain by at least one grade after pentagastrin stimulation during placebo treatment...

  8. The Effects of High-Frequency Transcutaneous Electrical Nerve Stimulation for Dental Professionals with Work-Related Musculoskeletal Disorders: A Single-Blind Randomized Placebo-Controlled Trial

    Directory of Open Access Journals (Sweden)

    Hye Rim Suh

    2015-01-01

    Full Text Available Work-related musculoskeletal symptom disorders (WMSDs have a significant issue for dental professionals. This study investigated the effects of high-frequency transcutaneous electrical nerve stimulation (TENS on work-related pain, fatigue, and the active range of motion in dental professionals. Among recruited 47 dental professionals with WMSDs, 24 subjects received high-frequency TENS (the TENS group, while 23 subjects received placebo stimulation (the placebo group. TENS was applied to the muscle trigger points of the levator scapulae and upper trapezius, while placebo-TENS was administered without electrical stimulation during 60 min. Pain and fatigue at rest and during movement were assessed using the visual analog scale (VAS, pain pressure threshold (PPT, and active range of motion (AROM of horizontal head rotation at six time points: prelabor, postlabor, post-TENS, and at 1 h, 3 h, and 1 day after TENS application. Both groups showed significantly increased pain and fatigue and decreased PPT and AROM after completing a work task. The TENS group showed significantly greater improvements in VAS score, fatigue, PPT, and AROM at post-TENS and at 1 h and 3 h after application (all P < 0.05 as compared to the placebo group. A single session high-frequency TENS may immediately reduce symptoms related to WMSDs in dental professionals.

  9. Microcurrent Point Stimulation Applied to Lower Back Acupuncture Points for the Treatment of Nonspecific Neck Pain.

    Science.gov (United States)

    Armstrong, Kelly; Gokal, Raman; Chevalier, Antoine; Todorsky, William; Lim, Mike

    2017-04-01

    Although acupuncture and microcurrent are widely used for chronic pain, there remains considerable controversy as to their therapeutic value for neck pain. We aimed to determine the effect size of microcurrent applied to lower back acupuncture points to assess the impact on the neck pain. This was a cohort analysis of treatment outcomes pre- and postmicrocurrent stimulation, involving 34 patients with a history of nonspecific chronic neck pain. Consenting patients were enrolled from a group of therapists attending educational seminars and were asked to report pain levels pre-post and 48 hours after a single MPS application. Direct current microcurrent point stimulation (MPS) applied to standardized lower back acupuncture protocol points was used. Evaluations entailed a baseline visual analog scale (VAS) pain scale assessment, using a VAS, which was repeated twice after therapy, once immediately postelectrotherapy and again after a 48-h follow-up period. All 34 patients received a single MPS session. Results were analyzed using paired t tests. Results and Outcomes: Pain intensity showed an initial statistically significant reduction of 68% [3.9050 points; 95% CI (2.9480, 3.9050); p = 0.0001], in mean neck pain levels after standard protocol treatment, when compared to initial pain levels. There was a further statistically significant reduction of 35% in mean neck pain levels at 48 h when compared to pain levels immediately after standard protocol treatment [0.5588 points; 95% CI (0.2001, 0.9176); p = 0.03], for a total average pain relief of 80%. The positive results in this study could have applications for those patients impacted by chronic neck pain.

  10. Ultrasound combined transcutaneous electrical nerve stimulation (UltraTENS) versus phonophoresis of piroxicam (PhP) in symptomatic knee osteoarthritis: A randomized double-blind, controlled trial.

    Science.gov (United States)

    Boonhong, Jariya; Suntornpiyapan, Phitsanu

    2018-02-02

    Ultrasound combined with transcutaneous electrical nerve stimulation (UltraTENS) and phonophoresis of piroxicam (PhP) are combined modality therapy that frequently used in musculoskeletal pain including knee osteoarthritis (OA). But it is lack of a good clinical trial to prove and compare their effects. To compare the effects of UltraTENS with PhP on mild to moderate degree of symptomatic knee OA. Sixty-one patients (55 women), mean age of 63.4 ± 8.1 y, 50-90 mm VAS of knee pain and Kellgren-Lawrence score of grade I-III were randomly allocated into UltraTENS and PhP (N = 31 and 30, respectively). The UltraTENS group received a combined ultrasound with TENS program and a non-drug gel, whereas the PhP group got an ultrasound program with piroxicam gel and sham TENS. All patients were treated for a total of 10 sessions, consisting of five times per week and 10 min per session. Before and after treatment, patients were evaluated knee pain by using the 100-mm VAS and functional performance by Western Ontario and McMaster Universities Osteoarthritis (WOMAC) index. The UltraTENS and PhP groups experienced considerable improvement in both VAS and total WOMAC scores post-treatment (PPhP had better VAS of pain and WOMAC scores but no statistical significance. Results show that UltraTENS and PhP were effective for relieving pain and improve functionality knee OA without significant differences between their effects.

  11. Early Identification and Infant Stimulation

    Science.gov (United States)

    Lintz, Brenda

    1976-01-01

    This article describes the Zucker Center's program in Toledo, Ohio which identifies children with developmental delays and enrolls them in a demonstration infant stimulation program. The center provides educational programs in neonatal care, nutrition, general stimulation, and parenting techniques. Available from: PS 504 969. (JMB)

  12. Subliminal Stimulation: Hoax or Reality?

    Science.gov (United States)

    Trank, Douglas M.

    Subliminal stimulation is defined as that which is perceived by an individual below the threshold of awareness or cognizance. This article traces the history of research in subliminal stimulation to illustrate that under certain circumstances and conditions, this behavioral phenomenon does occur. Although subliminal stimuli do affect human…

  13. EOR by stimulated microflora

    Energy Technology Data Exchange (ETDEWEB)

    Svarovskaya, L.I.; Altunina, L.K.; Rozhenkova, Z.A.; Bulavin, V.D. [Institute of Petroleum Chemistry, Tomsk (Russian Federation)

    1995-12-31

    A combined microbiological and physico-chemical method for EOR has been developed for flooded West Siberia oil fields with formation temperature of 45{degrees}-95{degrees}C (318-365K). Formation water includes rich and various biocenoses numbering up to 2 x 10{sup 7} cells per ml. Representatives of genera, i.e, Pseudomonas, Bacillus, Actinomyces, Micrococcus, Mycobacterium, Sarcina, etc. were found to be the most widely distributed microorganisms. The method is based on injection of systems exhibiting high oil displacing capacity and at the same time being an additional nitrous nutrient for endemic populations of microorganisms. Their injection into formation water favors biomass growth by 4-6 orders and promotes syntheses of biosurfactants, biopolymers, acids, etc., and gaseous products. The features of residual oil displacement have been studied on laboratory models using a combined microbiological and physico-chemical method. A curve for the yield of residual oil is presented by two peaks. The first peak is stipulated by the washing action of oil displacement system, and the second one by the effect of metabolites produced at stimulation of biogenic processes. Oil displacement index increases by 15%-30%.

  14. Cardiovascular stimulant actions of bupropion in comparison to cocaine in the rat.

    Science.gov (United States)

    Killian, Lyndsey M; Docherty, James R

    2014-07-15

    Stimulants are banned in competition by the World Anti-Doping Agency, except for a small number of therapeutic agents subject to monitoring, including bupropion. We have examined the potency of bupropion in comparison with two agents banned in competition, adrafinil and modafinil, and with cocaine and desipramine as blockers of the noradrenaline re-uptake transporter in peripheral tissues of the rat. For studies in vivo, the pressor response to noradrenaline in the anaesthetized rat was studied. Cocaine, desipramine and bupropion at doses of 0.1, 0.3 and 1mg/kg, respectively, significantly increased the pressor response to noradrenaline. Overall, cocaine and desipramine were approximately 2-5 times more potent than bupropion in vivo in the rat. Adrafinil and modafinil (both 3mg/kg) did not significantly affect the pressor response. Bupropion was chosen for further study. In 1Hz paced rat right ventricular strips, bupropion (30μM) significantly increased the potency of noradrenaline at increasing the force of contraction. In rat vas deferens, bupropion and cocaine produced concentration-dependent increases in the contractile response to nerve stimulation, and cocaine was 11 times more potent than bupropion. Since bupropion is used clinically in doses of up to 300mg, it is likely that bupropion has actions at the noradrenaline transporter, and thus cardiovascular stimulant actions, in clinical doses. This may explain findings of increased exercise performance with bupropion. Copyright © 2014 Elsevier B.V. All rights reserved.

  15. Modulation of neck muscle activity induced by intra-oral stimulation in humans.

    Science.gov (United States)

    Torisu, Tetsurou; Tanaka, Mihoko; Murata, Hiroshi; Wang, Kelun; Arendt-Nielsen, Lars; De Laat, Antoon; Svensson, Peter

    2014-05-01

    To investigate the effect of painful electrical stimuli applied to intra-oral tissues around the teeth on the neck muscle activity in healthy humans. Electromyographic (EMG) responses of the dorsal neck muscles evoked by intra-oral electrical stimulation were recorded before and after local anesthesia to the stimulus site in 17 healthy volunteers. Inhibition of dorsal neck muscle EMG activities on average 80% compared to baseline level was observed with a latency around 50 ms after the electrical stimulation before anesthesia, and the EMG activity inhibition decreased after anesthesia of the intra-oral stimulus site. The perceived intensity of the electrical stimuli as scored on a visual analogue scale (VAS) was 6.1 ± 0.4 cm before anesthesia and 1.5 ± 0.2 cm after anesthesia. Intra-oral stimulation can inhibit neck muscle activity. This modulation might be attributed mainly to nociceptive afferent nerves however, non-nociceptive fibers could also be responsible. Intra-oral information including nociceptive activity can inhibit neck muscle activity. From a clinical viewpoint, the present findings demonstrate the neural connectivity between the trigeminal region and the cervical region raising the possibility that orofacial pain conditions could influence head, neck and shoulder activity. Copyright © 2013 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.

  16. Nanomaterial-enabled neural stimulation

    Directory of Open Access Journals (Sweden)

    Yongchen eWang

    2016-03-01

    Full Text Available Neural stimulation is a critical technique in treating neurological diseases and investigating brain functions. Traditional electrical stimulation uses electrodes to directly create intervening electric fields in the immediate vicinity of neural tissues. Second-generation stimulation techniques directly use light, magnetic fields or ultrasound in a non-contact manner. An emerging generation of non- or minimally invasive neural stimulation techniques is enabled by nanotechnology to achieve a high spatial resolution and cell-type specificity. In these techniques, a nanomaterial converts a remotely transmitted primary stimulus such as a light, magnetic or ultrasonic signal to a localized secondary stimulus such as an electric field or heat to stimulate neurons. The ease of surface modification and bio-conjugation of nanomaterials facilitates cell-type-specific targeting, designated placement and highly localized membrane activation. This review focuses on nanomaterial-enabled neural stimulation techniques primarily involving opto-electric, opto-thermal, magneto-electric, magneto-thermal and acousto-electric transduction mechanisms. Stimulation techniques based on other possible transduction schemes and general consideration for these emerging neurotechnologies are also discussed.

  17. Electrical stimulation in exercise training

    Science.gov (United States)

    Kroll, Walter

    1994-01-01

    Electrical stimulation has a long history of use in medicine dating back to 46 A.D. when the Roman physician Largus found the electrical discharge of torpedo fishes useful in the treatment of pain produced by headache and gout. A rival Greek physician, Dioscorides, discounted the value of the torpedo fish for headache relief but did recommend its use in the treatment of hemorrhoids. In 1745, the Leyden jar and various sized electrostatic generators were used to treat angina pectoris, epilepsy, hemiplegia, kidney stones, and sciatica. Benjamin Franklin used an electrical device to treat successfully a young woman suffering from convulsive fits. In the late 1800's battery powered hydroelectric baths were used to treat chronic inflammation of the uterus while electrified athletic supporters were advertised for the treatment of male problems. Fortunately, such an amusing early history of the simple beginnings of electrical stimulation did not prevent eventual development of a variety of useful therapeutic and rehabilitative applications of electrical stimulation. Over the centuries electrical stimulation has survived as a modality in the treatment of various medical disorders with its primary application being in the rehabilitation area. Recently, a surge of new interest in electrical stimulation has been kindled by the work of a Russian sport scientist who reported remarkable muscle strength and endurance improvements in elite athletes. Yakov Kots reported his research on electric stimulation and strength improvements in 1977 at a Canadian-Soviet Exchange Symposium held at Concordia University in Montreal. Since then an explosion of new studies has been seen in both sport science and in medicine. Based upon the reported works of Kots and the present surge of new investigations, one could be misled as to the origin of electrical stimulation as a technique to increase muscle strength. As a matter of fact, electric stimulation has been used as a technique to improve

  18. Low intensity transcranial electric stimulation

    DEFF Research Database (Denmark)

    Antal, A.; Alekseichuk, I.; Bikson, M.

    2017-01-01

    Low intensity transcranial electrical stimulation (TES) in humans, encompassing transcranial direct current (tDCS), transcutaneous spinal Direct Current Stimulation (tsDCS), transcranial alternating current (tACS), and transcranial random noise (tRNS) stimulation or their combinations, appears...... to suboptimal electrode-skin contact. Very rarely mania or hypomania was induced in patients with depression (11 documented cases), yet a causal relationship is difficult to prove because of the low incidence rate and limited numbers of subjects in controlled trials. Mild AEs (MAEs) include headache and fatigue...

  19. Gastric Electrical Stimulation

    Science.gov (United States)

    2006-01-01

    Executive Summary Objective The objective of this analysis was to assess the effectiveness, safety and cost-effectiveness of gastric electrical stimulation (GES) for the treatment of chronic, symptomatic refractory gastroparesis and morbid obesity. Background Gastroparesis - Epidemiology Gastroparesis (GP) broadly refers to impaired gastric emptying in the absence of obstruction. Clinically, this can range from the incidental detection of delayed gastric emptying in an asymptomatic person to patients with severe nausea, vomiting and malnutrition. Symptoms of GP are nonspecific and may mimic structural disorders such as ulcer disease, partial gastric or small bowel obstruction, gastric cancer, and pancreaticobiliary disorders. Gastroparesis may occur in association with diabetes, gastric surgery (consequence of peptic ulcer surgery and vagotomy) or for unknown reasons (idiopathic gastroparesis). Symptoms include early satiety, nausea, vomiting, abdominal pain and weight loss. The majority of patients with GP are women. The relationship between upper gastrointestinal symptoms and the rate of gastric emptying is considered to be weak. Some patients with markedly delayed gastric emptying are asymptomatic and sometimes, severe symptoms may remit spontaneously. Idiopathic GP may represent the most common form of GP. In one tertiary referral retrospective series, the etiologies in 146 GP patients were 36% idiopathic, 29% diabetic, 13% postgastric surgery, 7.5% Parkinson’s disease, 4.8% collagen vascular disorders, 4.1% intestinal pseudoobstruction and 6% miscellaneous causes. The true prevalence of digestive symptoms in patients with diabetes and the relationship of these symptoms to delayed gastric emptying are unknown. Delayed gastric emptying is present in 27% to 58% of patients with type 1 diabetes and 30% with type 2 diabetes. However, highly variable rates of gastric emptying have been reported in type 1 and 2 diabetes, suggesting that development of GP in

  20. Subcutaneous Stimulation as an Additional Therapy to Spinal Cord Stimulation for the Treatment of Low Back Pain and Leg Pain in Failed Back Surgery Syndrome: Four-Year Follow-Up.

    Science.gov (United States)

    Hamm-Faber, Tanja E; Aukes, Hans; van Gorp, Eric-Jan; Gültuna, Ismail

    2015-10-01

    The objective of this study is to investigate the efficacy of long-term follow-up of subcutaneous stimulation (SubQ) as an additional therapy for patients with failed back surgery syndrome (FBSS) with chronic refractory pain, for whom spinal cord stimulation (SCS) alone was unsuccessful in treating low back pain. Prospective case series. FBSS patients with leg and/or low back pain whose conventional therapies had failed, received a combination of SCS (8-contact Octad lead, 3877-45 cm, Medtronic, Minneapolis, MN, USA) and/or SubQ (4-contact Quad Plus lead (s), 2888-28 cm, Medtronic). Initially, an Octad lead was placed in the epidural space for SCS for a trial stimulation to assess the suppression of leg and/or low back pain. Where SCS alone was insufficient in treating low back pain, lead(s) were placed superficially in the subcutaneous tissue of the lower back, exactly in the middle of the pain area. A pulse generator (Prime Advanced, 37702, Medtronic) was implanted if the patient reported more than 50% pain relief during the trial period. We investigated the long-term effect of neuromodulation on pain with the visual analog scale (VAS), and disability using the Quebec Pain Disability Scale. The results after 46 months are presented. Eleven patients, five men and six women (age 51 ± 8 years, mean ± SD) were included in the pilot study. In nine cases, SCS was used in combination with SubQ leads. Two patients received only SubQ leads. In one patient, the SCS + SubQ system was removed after nine months and these results were not taken into account for the analysis. Baseline scores for leg (N = 8) and low back pain (N = 10) were VASbl: 59 ± 15 and VASbl: 63 ± 14, respectively. The long-term follow-up period was 46 ± 4 months. SCS significantly reduced leg pain after 12 months (VAS12: 20 ± 11, p12 = 0.001) and 46 months (VAS46: 37 ± 17, p46 = 0.027). Similarly, SubQ significantly reduced back pain after 12 months(VAS12: 33 ± 16, p12 = 0.001) and 46 months

  1. Geothermal Reservoir Well Stimulation Program: technology transfer

    Energy Technology Data Exchange (ETDEWEB)

    1980-05-01

    The following are included: review of available data from previous fracturing stimulation operations, stimulation process variables, fracturing fluid design, hydraulic fracture design, stimulation case histories, and selected bibliography. (MHR)

  2. Transcranial Magnetic Stimulation for Schizophrenia

    National Research Council Canada - National Science Library

    Dougall, Nadine; Maayan, Nicola; Soares-Weiser, Karla; McDermott, Lisa M; McIntosh, Andrew

    2015-01-01

    .... One proposed alternative to drug treatments is transcranial magnetic stimulation (TMS). To date, many research trials to assess effectiveness of TMS for people with symptoms of schizophrenia have been conducted worldwide...

  3. Enteral feeding without pancreatic stimulation

    DEFF Research Database (Denmark)

    Kaushik, Neeraj; Pietraszewski, Marie; Holst, Jens Juul

    2005-01-01

    .5 g protein/kg ideal body weight/d. Plasma gut peptide responses were monitored in 15 subjects. RESULTS: In comparison with basal fasting trypsin secretion rates (mean = 134 [standard error = 22] U/h), duodenal feeding with the polymeric and elemental formulae stimulated trypsin secretion (mean = 408...... in enteral feeding without pancreatic stimulation, with particular reference to trypsin, because the avoidance of trypsin stimulation may optimize enteral feeding in acute pancreatitis. METHODS: The pancreatic secretory responses to feeding were studied in 36 healthy volunteers by standard double...... [standard error = 51] U/h; P standard error = 34] U/h) and mid-distal jejunal (mean = 119 [standard error = 16] U/h) did not. Stimulation was associated with an increase in plasma cholecystokinin, whereas distal jejunal feeding resulted in an increase...

  4. Mechanisms of deep brain stimulation

    National Research Council Canada - National Science Library

    Herrington, Todd M; Cheng, Jennifer J; Eskandar, Emad N

    2016-01-01

    Deep brain stimulation (DBS) is widely used for the treatment of movement disorders including Parkinson's disease, essential tremor, and dystonia and, to a lesser extent, certain treatment-resistant neuropsychiatric disorders...

  5. Transcranial electrical stimulation: An introduction

    CERN Document Server

    Tarazona, Carlos G; Chávez, Laura; Andrade, Sebastián

    2015-01-01

    The main objective of the electrical stimulation of the brain is to generate action potentials from the application of electromagnetic fields. Among the available techniques, transcranial electrical stimulation (TES) represents a popular method of administration that has the advantage of being non-invasive and economically more affordable. This article aims to briefly introduce the reader into the understanding of TES in terms of the physics involved as well as for some of the relevant results of studies applying this technique.

  6. Deep Brain Stimulation for Parkinson's Disease

    Science.gov (United States)

    ... Home » Disorders » All Disorders Deep Brain Stimulation for Parkinson's Disease Information Page Deep Brain Stimulation for Parkinson's Disease Information Page What research is being done? The ...

  7. Comparison of effectiveness of Transcutaneous Electrical Nerve Stimulation and Kinesio Taping added to exercises in patients with myofascial pain syndrome.

    Science.gov (United States)

    Azatcam, Gokmen; Atalay, Nilgun Simsir; Akkaya, Nuray; Sahin, Fusun; Aksoy, Sibel; Zincir, Ozge; Topuz, Oya

    2017-01-01

    Although there are several studies of Transcutaneous Electrical Nerve Stimulation (TENS) and exercise in myofascial pain syndrome, there are no studies comparing the effectiveness of Kinesio Taping (KT) and TENS in myofascial pain syndrome patients. To compare the early and late effects of TENS and KT on pain, disability and range of motion in myofascial pain syndrome patients. Sixty-nine patients were divided into three groups randomly as TENS+Exercise, KT+Exercise and exercise groups. Visual Analogue Scale (VAS), pain threshold, Neck Disability Index and cervical contralateral lateral flexion were employed in the evaluation of the patients performed before treatment, after treatment and 3rd month after treatment. The VAS, pain threshold, Neck Disability Index and contralateral lateral flexion values were improved in all groups both in after treatment and 3rd month after treatment (ppain severity and increase pain threshold, function and cervical range of motion in myofascial pain syndrome patients. Addition of TENS or KT to the exercise therapy resulted in more significant improvement compared to exercise therapy alone with a more pronounced improvement in KT group compared to the TENS group in the early period. Because KT was found to be more effective in decreasing the pain and had the advantage of being used in every 3 days, it seems to be beneficial in acute painful periods in myofascial pain syndrome patients.

  8. The Effectiveness of Transcutaneous Electrical Nerve Stimulation in Knee Osteoarthritis with Neuropathic Pain Component: A Randomized Controlled Study

    Directory of Open Access Journals (Sweden)

    Cemile Sevgi Polat

    2018-01-01

    Full Text Available Objective: The aim of our study was to assess the efficacy of transcutaneous electrical nerve stimulation (TENS in knee osteoarthritis with neuropathic pain component. Materials and Methods: The patients were assessed by visual analogue scale (VAS for pain severity, Western Ontario and McMaster osteoarthritis index (WOMAC for physical function and the Kellgren-Lawrence system for severity of osteoarthritis, painDETECT questionnaire for presence of neuropathic pain. Patients were divided into two groups according to painDETECT questionnaire scores. Group 1 consisted of 20 patients (39.2% with likely and possible neuropathic pain, group 2 consisted of 31 patients (60.8% with unlikely neuropathic pain. All patients received hot pack, TENS and home exercise program was given. Physical therapy agents were given for 3 weeks, 5 days a week. Assessments were evaluated in all patients before and after the treatment. Results: There was no statistically significant difference in demographic features and radiographic evaluations between the groups. The VAS, WOMAC pain and physical function scores were significantly lower after treatment in knee patients with neuropathic pain component, but there was no significant difference between the two groups. Conclusion: TENS is a neuropathic pain component in knee osteoarthritis patients, which is effective in reducing pain and improving physical function. The benefit of TENS therapy is that it can be used in conjunction with drug therapy, thereby reducing the drug dose and drug side effects.

  9. Chemosensory stimulation during sleep - Arousal responses to gustatory stimulation.

    Science.gov (United States)

    Stuck, B A; Moutsis, T T; Bingel, U; Sommer, J U

    2016-05-13

    The processing of nociceptive, visual, vibrotactile, thermal and acoustic stimuli during sleep has been extensively investigated in the past. Recently, interest has focused on the impact of olfactory stimulation on sleep. In contrast to all other sensory systems, olfactory stimulation does not lead to an increased arousal frequency, regardless of hedonicity and concentration. The impact of the second chemosensory system, gustation, on sleep however has not been investigated to date. Twenty-one normosmic and normogeusic volunteers of both genders, aged 19-33 years, participated in the trial. Stimulation was performed with a gustometer using the following aqueous solutions: saccharose 20% (sweet), sodium chloride (NaCl) 7.5% (salty), citrate 5% (sour), and quinine 0.02% (bitter). A tasteless solution was used as negative control. Capsaicin, a strong trigeminal stimulus, served as positive control. Primary outcome was arousal frequency per stimulus in each sleep stage, as assessed with polysomnography. The frequency of arousals decreased in deeper sleep stages (N1: 211 arousals of 333 stimuli=63%, N2: 676/2728=25%, N3: 43/1378=3%, REM: 57/1010=6%). Statistically significant differences in terms of arousal frequency were found in N2 between the negative control and NaCl 100 μl (pgustatory stimulation during sleep induces arousals depending on stimulus intensity and sleep stage, which is different to olfactory stimulation and may be related to differences in central processing of the two chemosensory systems. Copyright © 2016 IBRO. Published by Elsevier Ltd. All rights reserved.

  10. Hospitālas urrīnceļu infekcijas profilakse un ārstēšana pie mazinvazīvas uroloģiskas iejaukšanās

    OpenAIRE

    Ņemirovska, Irina

    2015-01-01

    Urīnceļu infekcija pacientiem pēc ureteroskopiskas operācijas (URS) pie nierakmeņu slimības (NAS) ir nozīmīga medicīniska problēma. URS ir ļoti bieža un droša ambulatorā procedūra. Tomēr komplikācijas ir un tās neaprobežojas ar infekciju. Pētījuma mērķis un metodes: Zinātniskā pētījuma primārais mērķis bija iegūt datus par urīnceļu infekciju biežumu pēc mazinvazīvas uroloģiskas iejaukšanas (pēc NAS) Latvijā PSKUS Uroloģijas nodaļā un izanalizēt urīnceļu infekcijas epidemioloģiju, riska ...

  11. Nākotnes perspektīvas suverēnās labklājības fondu darbībā Persijas Līča Sadarbības padomes reģionā

    OpenAIRE

    Broka, Sintija

    2015-01-01

    Mana bakalaura darba tēma ir „Nākotnes perspektīvas suverēnās labklājības fondu darbībā Persijas Līča Sadarbības Padomes reģionā”. Mērķis ir izpētīt, suverēnās labklājības fondu attīstību nākotnē. Uzdevumi - starptautiskās finanšu sistēmas raksturojums, reģiona un turētājvalstu ekonomisko rādītāju, dokumentācijas un informācijas avotu analīze. Pētījums - trīs suverēnās labklājības fondu rādītāju analīze, stratēģiju noteikšana, darbības apjoma pieauguma radītāju analīze un secinājumu veidošan...

  12. Use of transcutaneous electrical nerve stimulation as an adjunctive to epidural analgesia in the management of acute thoracotomy pain

    Directory of Open Access Journals (Sweden)

    Alka Chandra

    2010-01-01

    Full Text Available The present randomized study was conducted in our institute of pulmonary medicine and tuberculosis over a period of 1 year. This study aimed to evaluate the effectiveness of transcutaneous electrical nerve stimulation (TENS as an adjunctive to thoracic epidural analgesia for the treatment of postoperative pain in patients who underwent posterolateral thoracotomy for decortication of lung. Sixty patients in the age group 15-40 years scheduled to undergo elective posterolateral thoracotomy were divided into two groups of 30 each. Patients were alternatively assigned to one of the groups. In group I, only thoracic epidural analgesia with local anaesthetics was given at regular intervals; however, an identical apparatus which did not deliver an electric current was applied to the control (i.e. group I patients. While in group II, TENS was started immediately in the recovery period in addition to the epidural analgesia. A 0-10 visual analog scale (VAS was used to assess pain at regular intervals. The haemodynamics were also studied at regular intervals of 2 h for the first 10 h after the surgery. When the VAS score was more than three, intramuscular analgesia with diclofenac sodium was given. The VAS score and the systolic blood pressure were comparable in the immediate postoperative period (P = NS but the VAS score was significantly less in group II at 2, 4, 6, 8 h (P < 0.01, P < 0.05, P < 0.05, P < 0.05, respectively, and at 10 h the P value was not significant. Similarly, the systolic blood pressure was significantly less in group II at 2, 4, 6 h after surgery, that is P < 0.02, P < 0.01, P < 0.01, respectively, but at 8 and 10 h the pressures were comparable in both the groups. Adding TENS to epidural analgesia led to a significant reduction in pain with no sequelae. The haemodynamics were significantly stable in group II compared to group I. TENS is a valuable strategy to alleviate postoperative pain following thoracic surgery with no side

  13. Reducing Prejudice Through Brain Stimulation.

    Science.gov (United States)

    Sellaro, Roberta; Derks, Belle; Nitsche, Michael A; Hommel, Bernhard; van den Wildenberg, Wery P M; van Dam, Kristina; Colzato, Lorenza S

    2015-01-01

    Social categorization and group identification are essential ingredients for maintaining a positive self-image that often lead to negative, implicit stereotypes toward members of an out-group. The medial prefrontal cortex (mPFC) may be a critical component in counteracting stereotypes activation. Here, we assessed the causal role of the mPFC in these processes by non-invasive brain stimulation via transcranial direct current stimulation (tDCS). Participants (n = 60) were randomly and equally assigned to receive anodal, cathodal, or sham stimulation over the mPFC while performing an Implicit Association Test (IAT): They were instructed to categorize in-group and out-group names and positive and negative attributes. Anodal excitability-enhancing stimulation decreased implicit biased attitudes toward out-group members compared to excitability-diminishing cathodal and sham stimulation. These results provide evidence for a critical role of the mPFC in counteracting stereotypes activation. Furthermore, our results are consistent with previous findings showing that increasing cognitive control may overcome negative bias toward members of social out-groups. Copyright © 2015 Elsevier Inc. All rights reserved.

  14. Evoked Electromyographically Controlled Electrical Stimulation

    Directory of Open Access Journals (Sweden)

    Mitsuhiro Hayashibe

    2016-07-01

    Full Text Available Time-variant muscle responses under electrical stimulation (ES are often problematic for all the applications of neuroprosthetic muscle control. This situation limits the range of ES usage in relevant areas, mainly due to muscle fatigue and also to changes in stimulation electrode contact conditions, especially in transcutaneous ES. Surface electrodes are still the most widely used in noninvasive applications.Electrical field variations caused by changes in the stimulation contact condition markedly affect the resulting total muscle activation levels. Fatigue phenomena under functional electrical stimulation (FES are also well known source of time-varying characteristics coming from muscle response under ES. Therefore it is essential to monitor the actual muscle state and assess the expected muscle response by ES so as to improve the current ES system in favour of adaptive muscle-response-aware FES control. To deal with this issue, we have been studying a novel control technique using evoked electromyography (eEMG signals to compensate for these muscle time-variances under ES for stable neuroprosthetic muscle control. In this perspective article, I overview the background of this topic and highlight important points to be aware of when using ES to induce the desired muscle activation regardless of the time-variance. I also demonstrate how to deal with the common critical problem of ES to move toward robust neuroprosthetic muscle control with the Evoked Electromyographically Controlled Electrical Stimulation paradigm.

  15. Ovarian stimulation, endometrium and implantation

    Directory of Open Access Journals (Sweden)

    mandana Beigi Boroujeni

    2011-03-01

    Full Text Available In the Paper article, the collection of the studies related to the effect of ovarian stimulation on endometrium of uterus and implantation have been investigated. History: Monash group used ovarian stimulation method for the first time in infertility treatment and also, they could increase the pregnancy rate using this method. However, the percentage of successful embryonic implantation has been decreased by this method due to imbalance of hormones and the effect of these hormonal changes on endometrium. Materials and Methods: Studies done by researchers have shown that ovarian stimulation causes undesirable changes in endometrium which in turn such alterations lead to inadequate attachment of embryo to endometrium and finally decrease the percentage of embryonic implantation. Conclusion: Based on several researches and the importance of using the ovarian stimulation method in treatment of infertility, also due to undesirable effects that ovarian stimulation has on endometrium during embryonic implantation it is inevitable that more investigations should be done for improvement of treatment methods in infertility clinics.

  16. Role of transcutaneous electric nerve stimulation in the management of trigeminal neuralgia

    Directory of Open Access Journals (Sweden)

    Sanju Singla

    2011-01-01

    Full Text Available Background: Trigeminal neuralgia typically involves nerves supplying teeth, jaws and face of older females. Though the etiology is usually obscure, different treatment modalities have been tried for it viz. medicinal treatment, injection alcohol, peripheral neurectomy, rhizotomy, and microvascular decompression etc. Transcutaneous electric nerve stimulation (TENS is an emerging and promising option for management of such patients. Aims and Design: The present study was designed with an aim to study the efficacy of TENS in management of trigeminal neuralgia. Materials and Methods: The study was conducted on 30 patients of trigeminal neuralgia confirmed by diagnostic nerve block. They were given bursts of TENS for 20-40 days over the path of the affected nerve and subsequently evaluated at 1 month and 3 month intervals by visual analogue scale (VAS, verbal pain scale (VPS, a functional outcome scales for main daily activities like sleep, chewing, talking, or washing face. Results: The results showed that, on VAS, the score decreased from 8.9 (Pre TENS to 3.1 at 1 month and 1.3 at 3 months, and on VPS, the score decreased from 3.5 (Pre TENS to 1.2 at 1 month and 0.3 at 3 months. Similarly, a considerable decrease in scores was seen on functional outcome scale for different activities. No side effects like irritation or redness of skin were seen in any of the patients. Conclusions: Thus, TENS was found to be a safe, easily acceptable, and non-invasive outdoor patient department procedure for management of trigeminal neuralgia.

  17. [Optimal acupoint combination of transcutaneous electrical stimulation in artificial abortion operation].

    Science.gov (United States)

    Chen, Chong; Xie, Wenxia; Wang, Zedong; Zeng, Linchai; Liu, Pei; Li, Chunli

    2017-02-12

    To observe the clinical effects on analgesia, tranquilization and prevention of abortion syndrome of artificial abortion operation treated with transcutaneous electrical acupoint stimulation (TEAS) with different acupoint combination and explore the optimal acupoint combination of TEAS in artificial abortion operation. Two hundred patients intended to artificial operation were randomized into No.1 group[Sanyinjiao (SP 6) + Zusanli (ST 36)], No.2 group[Sanyinjiao (SP 6) + Diji (SP 8)], No.3 group[Sanyinjiao (SP 6) + Taichong (LR 3)], No.4 group (cervical blockage anesthesia with lidocaine) and No.5 group (blank group, without any analgesia measure applied), 40 cases in each one. In the No.1, No.2 and No.3 groups, Sanyinjiao (SP 6) was the main acupoint, combined with Zusanli (ST 36), Dijin (SP 8) and Taichong (LR 3) respectively. TEAS was given 30 min before the operation till the end of operation. Mean arterial pressure, heart rate and oxygen saturation during operation, as well as bleeding amount were observed in the five groups. The visual analogue scale (VAS) score was observed during and 30 min after operation, and Ramsay score was observed during operation. Cervical relaxation degree and the incidence of artificial abortion syndrome were recorded. For VAS score during and 30 min after operation and Ramsay score during operation, the differences were significant statistically in the No. 1, No.2, No.3 and No.4 groups as compared with the No.5 group (Partificial abortion syndrome, the incidences in the No.2 and No.3 groups were lower than those in the No.4 and No.5 groups (all P0.05). TEAS apparently reduces pain score during and 30 min after artificial abortion operation and achieves the satisfactory tranguilization effects. The combination of Sanyinjiao (SP 6) and Diji (SP 8) achieves the optimal effect of analgesia, tranquilization, dilating cervix and preventing from artificial abortion syndrome in the operation.

  18. Spinal Cord Stimulation for Refractory Angina Pectoris: A Systematic Review and Meta-analysis.

    Science.gov (United States)

    Pan, Xiaoxiao; Bao, Hongguang; Si, Yanna; Xu, Chenjie; Chen, Hao; Gao, Xianzhong; Xie, Xinyi; Xu, Yajie; Sun, Fan; Zeng, Lingqing

    2017-06-01

    Paresthesia-free stimulation such as high frequency and burst have been demonstrated as effective therapies for neuropathic pain. The aim of this meta-analysis was to evaluate the efficacy and safety of conventional spinal cord stimulation (SCS) in the treatment of refractory angina pectoris (RAP). Relevant randomized controlled trials that investigated SCS for patients with RAP were comprehensively searched in Medline, Pubmed, Embase, and Cochrane Library. Five meta-analyses were performed examining the changes in Canadian Cardiovascular Society classes, exercise time, Visual Analog Scale (VAS) scores of pain, Seattle Angina Questionnaire, and nitroglycerin use in RAP patients after SCS therapy. We analyzed standardized mean differences (MD) and 95% confidence intervals (CIs) for each outcome by Review Manager 5.0 and STATA 12.0. A total of 12 randomized controlled trials involving 476 RAP patients were identified. A trend of reduction in the angina frequency (MD=-9.03, 95% CI, -15.70 to -2.36) and nitroglycerin consumption (MD=-0.64, 95% CI, -0.84 to -0.45) could be observed in the SCS group. Compared with the control group, SCS showed benefit on increasing exercise time (MD=0.49, 95% CI, 0.13-0.85) and treatment satisfaction (MD=6.87, 95% CI, 2.07-11.66) with decreased VAS scores of pain (MD=-0.50, 95% CI, -0.81 to -0.20) and disease perception (MD=-8.34, 95% CI, -14.45 to -2.23). However, the result did not reach the significance level in terms of physical limitation (95% CI, -8.75 to 3.38; P=0.39) or angina stability (95% CI, -7.55 to 3.67; P=0.50). The current meta-analysis suggested that SCS was a potential alternative in the treatment of PAP patients. Further investigation for finding the appropriate intensity of stimulation is required before this treatment should be widely recommended and applied.

  19. Respiratory pathology in vibroacoustic disease: 25 years of research O aparelho respiratório na doença vibroacústica: 25 anos de investigação

    Directory of Open Access Journals (Sweden)

    Nuno A A Castelo Branco

    2007-01-01

    Full Text Available Background: Respiratory pathology induced by low frequency noise (LFN, Enquadramento: A patologia respiratória induzida pela exposição a ruído de baixa frequência (RBF, ¡Ü500 Hz, incluindo os infra-sons não constitui novidade dado que, desde 1960, no âmbito dos programas espaciais dos EUA e da União Soviética, diversos autores divulgaram a sua existência. No contexto da doença vibroacústica (VAD - vibroacoustic disease, uma patologia sistémica causada pela exposição excessiva a RBF, as lesões respiratórias apresentam características próprias. Inicialmente, esta patologia respiratória não foi tida como uma consequência da exposição ao ruído; no entanto, hoje, o RBF é considerado um agente muito importante de doença respiratória. O objectivo deste trabalho é sistematizar e actualizar todos os dados sobre a patologia respiratória observada na VAD. Métodos: Ao longo dos últimos 25 anos, recolheu-se informação, de modo continuado, de indivíduos e modelos animais expostos a RBF. Todos estes dados são aqui compilados. Resultados: Em indivíduos expostos a ruído no trabalho, as queixas brônquicas aparecem nos primeiros 4 anos de actividade e, nesta fase, reduzem ou desaparecem quando de férias ou removidos do seu local de trabalho por outros motivos. Com a exposição prolongada, poderão surgir situações mais graves, como derrames pleurais, insuficiência respiratória, fibrose pulmonar e carcinomas do aparelho respiratório. Não existe correlação com hábitos tabágicos. Em modelos animais expostos a RBF, apresentavam-se alterações morfológicas da pleura e perda da capacidade fagocítica das células mesoteliais (explicando os derrames pleurais observados. Foram observadas lesões de fibrose e neovascularização ao longo de todo o aparelho respiratório dos animais expostos. Também se identificaram lesões pré-malignas, metaplasia e displasia. Conclusões: O RBF é um agente de doença e tem como

  20. Retinal Stimulation on Rabbit Using Complementary Metal Oxide Semiconductor Based Multichip Flexible Stimulator toward Retinal Prosthesis

    Science.gov (United States)

    Tokuda, Takashi; Asano, Ryosuke; Sugitani, Sachie; Taniyama, Mari; Terasawa, Yasuo; Nunoshita, Masahiro; Nakauchi, Kazuaki; Fujikado, Takashi; Tano, Yasuo; Ohta, Jun

    2008-04-01

    The Functionality of a complementary metal oxide semiconductor (CMOS) LSI-based, multichip flexible retinal stimulator was demonstrated in retinal stimulation experiments on rabbits. A 1×4-configured multichip stimulator was fabricated for application to experiments on animals. An experimental procedure including surgical operations was developed, and retinal stimulation was performed with the fabricated multichip stimulator. Neural responses on the visual cortex were successfully evoked by the fabricated stimulator. The stimulator is confirmed to be applicable to acute animal experiments.

  1. Mechanisms of deep brain stimulation

    Science.gov (United States)

    Cheng, Jennifer J.; Eskandar, Emad N.

    2015-01-01

    Deep brain stimulation (DBS) is widely used for the treatment of movement disorders including Parkinson's disease, essential tremor, and dystonia and, to a lesser extent, certain treatment-resistant neuropsychiatric disorders including obsessive-compulsive disorder. Rather than a single unifying mechanism, DBS likely acts via several, nonexclusive mechanisms including local and network-wide electrical and neurochemical effects of stimulation, modulation of oscillatory activity, synaptic plasticity, and, potentially, neuroprotection and neurogenesis. These different mechanisms vary in importance depending on the condition being treated and the target being stimulated. Here we review each of these in turn and illustrate how an understanding of these mechanisms is inspiring next-generation approaches to DBS. PMID:26510756

  2. Bacterial contamination of test stimulation leads during percutaneous nerve stimulation.

    Science.gov (United States)

    Pannek, Jürgen; Grigoleit, Ute; Hinkel, Andreas

    2005-06-01

    To analyze the bacterial contamination of conventional percutaneous nerve stimulation (PNE) leads. Sacral neuromodulation has become an important tool for the treatment of urgency and chronic retention. Patients likely to benefit from this type of therapy are identified by PNE testing before implantation of the definitive system. Recently, a new system was introduced, using a self-blocking electrode that remains in place for both PNE testing and final implantation. PNE testing warrants an extracorporeal stimulator. Thus, using the same electrode for both external stimulation and definitive implantation may carry a significant risk of infection. Bilateral PNE testing was performed in 11 consecutive patients (8 women and 3 men, mean age 41.6 years) for either urgency (n = 7) or chronic retention (n = 4). Electrodes were placed under aseptic conditions and stimulated for 3 days. At the end of each test, the electrodes were removed and evaluated microbiologically. In 5 of the 11 patients (9 of 22 leads), significant bacterial growth was detected: Staphylococcus epidermidis in 5, Escherichia coli in 3, and Enterococcus faecalis in 1. However, no patient showed signs of inflammation at the electrode insertion sites. Bacterial growth was found in 45.5% of the patients after conventional PNE testing under aseptic conditions. Therefore, the new electrodes may well carry an elevated risk of infection. Infection of the implant can lead to major surgical revision or even explantation. Thus, additional studies of the infection risk of this new electrode are warranted before its general use can be recommended.

  3. Visual analogue scales (VAS): Measuring instruments for the documentation of symptoms and therapy monitoring in cases of allergic rhinitis in everyday health care: Position Paper of the German Society of Allergology (AeDA) and the German Society of Allergy and Clinical Immunology (DGAKI), ENT Section, in collaboration with the working group on Clinical Immunology, Allergology and Environmental Medicine of the German Society of Otorhinolaryngology, Head and Neck Surgery (DGHNOKHC)

    NARCIS (Netherlands)

    Klimek, Ludger; Bergmann, Karl-Christian; Biedermann, Tilo; Bousquet, Jean; Hellings, Peter; Jung, Kirsten; Merk, Hans; Olze, Heidi; Schlenter, Wolfgang; Stock, Philippe; Ring, Johannes; Wagenmann, Martin; Wehrmann, Wolfgang; Mösges, Ralph; Pfaar, Oliver

    2017-01-01

    Visual analogue scales (VAS) are psychometric measuring instruments designed to document the characteristics of disease-related symptom severity in individual patients and use this to achieve a rapid (statistically measurable and reproducible) classification of symptom severity and disease control.

  4. Mapping health assessment questionnaire disability index (HAQ-DI) score, pain visual analog scale (VAS), and disease activity score in 28 joints (DAS28) onto the EuroQol-5D (EQ-5D) utility score with the KORean Observational study Network for Arthritis (KORONA) registry data.

    Science.gov (United States)

    Kim, Hye-Lin; Kim, Dam; Jang, Eun Jin; Lee, Min-Young; Song, Hyun Jin; Park, Sun-Young; Cho, Soo-Kyung; Sung, Yoon-Kyoung; Choi, Chan-Bum; Won, Soyoung; Bang, So-Young; Cha, Hoon-Suk; Choe, Jung-Yoon; Chung, Won Tae; Hong, Seung-Jae; Jun, Jae-Bum; Kim, Jinseok; Kim, Seong-Kyu; Kim, Tae-Hwan; Kim, Tae-Jong; Koh, Eunmi; Lee, Hwajeong; Lee, Hye-Soon; Lee, Jisoo; Lee, Shin-Seok; Lee, Sung Won; Park, Sung-Hoon; Shim, Seung-Cheol; Yoo, Dae-Hyun; Yoon, Bo Young; Bae, Sang-Cheol; Lee, Eui-Kyung

    2016-04-01

    The aim of this study was to estimate the mapping model for EuroQol-5D (EQ-5D) utility values using the health assessment questionnaire disability index (HAQ-DI), pain visual analog scale (VAS), and disease activity score in 28 joints (DAS28) in a large, nationwide cohort of rheumatoid arthritis (RA) patients in Korea. The KORean Observational study Network for Arthritis (KORONA) registry data on 3557 patients with RA were used. Data were randomly divided into a modeling set (80 % of the data) and a validation set (20 % of the data). The ordinary least squares (OLS), Tobit, and two-part model methods were employed to construct a model to map to the EQ-5D index. Using a combination of HAQ-DI, pain VAS, and DAS28, four model versions were examined. To evaluate the predictive accuracy of the models, the root-mean-square error (RMSE) and mean absolute error (MAE) were calculated using the validation dataset. A model that included HAQ-DI, pain VAS, and DAS28 produced the highest adjusted R (2) as well as the lowest Akaike information criterion, RMSE, and MAE, regardless of the statistical methods used in modeling set. The mapping equation of the OLS method is given as EQ-5D = 0.95-0.21 × HAQ-DI-0.24 × pain VAS/100-0.01 × DAS28 (adjusted R (2) = 57.6 %, RMSE = 0.1654 and MAE = 0.1222). Also in the validation set, the RMSE and MAE were shown to be the smallest. The model with HAQ-DI, pain VAS, and DAS28 showed the best performance, and this mapping model enabled the estimation of an EQ-5D value for RA patients in whom utility values have not been measured.

  5. Visual analogue scales (VAS): Measuring instruments for the documentation of symptoms and therapy monitoring in cases of allergic rhinitis in everyday health care: Position Paper of the German Society of Allergology (AeDA) and the German Society of Allergy and Clinical Immunology (DGAKI), ENT Section, in collaboration with the working group on Clinical Immunology, Allergology and Environmental Medicine of the German Society of Otorhinolaryngology, Head and Neck Surgery (DGHNOKHC).

    Science.gov (United States)

    Klimek, Ludger; Bergmann, Karl-Christian; Biedermann, Tilo; Bousquet, Jean; Hellings, Peter; Jung, Kirsten; Merk, Hans; Olze, Heidi; Schlenter, Wolfgang; Stock, Philippe; Ring, Johannes; Wagenmann, Martin; Wehrmann, Wolfgang; Mösges, Ralph; Pfaar, Oliver

    2017-01-01

    Visual analogue scales (VAS) are psychometric measuring instruments designed to document the characteristics of disease-related symptom severity in individual patients and use this to achieve a rapid (statistically measurable and reproducible) classification of symptom severity and disease control. VAS can also be used in routine patient history taking and to monitor the course of a chronic disease such as allergic rhinitis (AR). More specifically, the VAS has been used to assess effectiveness of AR therapy in real life, both in intermittent and persistent disease. This position paper takes a detailed look at the historical development of VAS and its method-specific principles. Particular focus is put on aspects of practical application in daily routine and on a critical discussion of the advantages and disadvantages of the individual methods. VAS are well validated for the measurement of AR symptoms and correlate well with the ARIA (allergic rhinitis and its impact on asthma) severity classification and also correlated well with rTNSS and RQLQ. Moreover, several treatment studies on AR have used VAS as an evaluation parameter. Thanks to the use of new (real-life and real-time) communication technologies, such as smartphone apps, Discussion: VAS can be used relatively simply and highly effectively to assess disease control. The VAS lends itself very well to digitization and has now been incorporated into a smartphone app (called Allergy Diary) to assess AR control and direct treatment decisions as part of an AR clinical decision support system (CDSS). MASK Rhinitis has developed this app, which is currently available in 15 different languages.

  6. The image of war in the articles and notes of Vas. I. Nemirovich-Danchenko during the Russian-Turkish (1877—1878 and Russian-Japanese (1904—1905 wars: the stories and the social stereotypes which formed it

    Directory of Open Access Journals (Sweden)

    S. NOVIKOVA

    2014-02-01

    Full Text Available The article is devoted to the theme of forming the war image, in particular, considering the influence of Russian social stereotypes in the second half of 19th — early 20th century. The main sources of this work were the articles and notes that were creating by the famous journalist and writer Vas. I. Nemirovich-Danchenko. As a war correspondent he participated in almost all major conflicts of the second half of 19th — early 20th century and left a significant mark in j ournalism and literature. All ofthis works were written during Russian-Turkish (1877—1878 and Russian-Japanese (1904—1905 wars. These were not only main social fears and stereotypes of Russian society about coming war and enemy, but also the stories and collective images brought in the articles to make the stereotypes stronger or to deny it. Nemirovich-Danchenko developed his own personal collection of images and techniques, which he managed to convey the most delicate nuances necessary to achieve its objectives. Formed during the Russian-Turkish war this collection of images has undergone only minor changes. It enriched the author’s reflections on the theme of evolution wars that he had seen. Analysis of materials of this article was produced in accordance with modern views of the scientific community on the problems of formation of the images of war. The aim was to show the real influence of public attitudes and views on the development of stereotypes and their expression in the press. First of all it concerns the period immediately before the war and the development of pre-existing views. The author investigated the prognostic and simultaneous steps of forming the images of war, but left beyond reasoning retrospective (final view.

  7. Ovarian stimulation and embryo quality

    NARCIS (Netherlands)

    Baart, Esther; Macklon, Nick S.; Fauser, Bart J. C. M.

    To Study the effects of different ovarian stimulation approaches on oocyte and embryo quality, it is imperative to assess embryo quality with a reliable and objective method. Embryos rated as high quality by standardized morphological assessment are associated with higher implantation and pregnancy

  8. Thermally stimulated luminescence and photoluminescence ...

    Indian Academy of Sciences (India)

    Thermally stimulated luminescence (TSL) investigations of SrBPO5:Eu3+ and SrBPO5:Eu2+ phosphors were carried out in the temperature range of 300–650 K. In order to characterize the phosphors, X-ray diffraction and photoluminescence (PL) techniques were used. The emission spectrum of air heated SrBPO5:Eu3+ ...

  9. Orientation selective deep brain stimulation

    Science.gov (United States)

    Lehto, Lauri J.; Slopsema, Julia P.; Johnson, Matthew D.; Shatillo, Artem; Teplitzky, Benjamin A.; Utecht, Lynn; Adriany, Gregor; Mangia, Silvia; Sierra, Alejandra; Low, Walter C.; Gröhn, Olli; Michaeli, Shalom

    2017-02-01

    Objective. Target selectivity of deep brain stimulation (DBS) therapy is critical, as the precise locus and pattern of the stimulation dictates the degree to which desired treatment responses are achieved and adverse side effects are avoided. There is a clear clinical need to improve DBS technology beyond currently available stimulation steering and shaping approaches. We introduce orientation selective neural stimulation as a concept to increase the specificity of target selection in DBS. Approach. This concept, which involves orienting the electric field along an axonal pathway, was tested in the corpus callosum of the rat brain by freely controlling the direction of the electric field on a plane using a three-electrode bundle, and monitoring the response of the neurons using functional magnetic resonance imaging (fMRI). Computational models were developed to further analyze axonal excitability for varied electric field orientation. Main results. Our results demonstrated that the strongest fMRI response was observed when the electric field was oriented parallel to the axons, while almost no response was detected with the perpendicular orientation of the electric field relative to the primary fiber tract. These results were confirmed by computational models of the experimental paradigm quantifying the activation of radially distributed axons while varying the primary direction of the electric field. Significance. The described strategies identify a new course for selective neuromodulation paradigms in DBS based on axonal fiber orientation.

  10. Thermally stimulated scattering in plasmas

    DEFF Research Database (Denmark)

    Dysthe, K. B.; Mjølhus, E.; Pécseli, H. L.

    1985-01-01

    A theory for stimulated scattering of a laser beam is formulated where the dominant nonlinearity is the ohmic heating of the plasma. The analysis is carried out with particular reference to experimental investigations of CO2 laser heating of linear discharge plasma. In the conditions characterizing...

  11. Photoluminescence, thermally stimulated luminescence and ...

    Indian Academy of Sciences (India)

    Photoluminescence, thermally stimulated luminescence and electron paramagnetic resonance studies of U. 6+ doped BaSO4. M K BHIDE, T K SESHAGIRI. ∗. , SASHIKALA OJHA† and S V GODBOLE. Radiochemistry Division, †Radiation Safety Systems Division, Bhabha Atomic Research Centre, Mumbai 400 085, India.

  12. Stimulation of phagocytosis by sulforaphane

    Energy Technology Data Exchange (ETDEWEB)

    Suganuma, Hiroyuki, E-mail: hsuganu1@jhmi.edu [Lewis B. and Dorothy Cullman Cancer Chemoprotection Center, Department of Pharmacology and Molecular Sciences, Johns Hopkins University School of Medicine, 725 N. Wolfe Street, Baltimore, MD 21205 (United States); Fahey, Jed W., E-mail: jfahey@jhmi.edu [Lewis B. and Dorothy Cullman Cancer Chemoprotection Center, Department of Pharmacology and Molecular Sciences, Johns Hopkins University School of Medicine, 725 N. Wolfe Street, Baltimore, MD 21205 (United States); Bryan, Kelley E., E-mail: kbryanm1@jhmi.edu [Lewis B. and Dorothy Cullman Cancer Chemoprotection Center, Department of Pharmacology and Molecular Sciences, Johns Hopkins University School of Medicine, 725 N. Wolfe Street, Baltimore, MD 21205 (United States); Healy, Zachary R., E-mail: zhealy1@jhmi.edu [Lewis B. and Dorothy Cullman Cancer Chemoprotection Center, Department of Pharmacology and Molecular Sciences, Johns Hopkins University School of Medicine, 725 N. Wolfe Street, Baltimore, MD 21205 (United States); Talalay, Paul, E-mail: ptalalay@jhmi.edu [Lewis B. and Dorothy Cullman Cancer Chemoprotection Center, Department of Pharmacology and Molecular Sciences, Johns Hopkins University School of Medicine, 725 N. Wolfe Street, Baltimore, MD 21205 (United States)

    2011-02-04

    Research highlights: {yields} Sulforaphane stimulates the phagocytosis of RAW 264.7 macrophages under conditions of serum deprivation. {yields} This effect does not require Nrf2-dependent induction of phase 2 genes. {yields} Inactivation of macrophage migration inhibitory factor (MIF) by sulforaphane may be involved in stimulation of phagocytosis by sulforaphane. -- Abstract: Sulforaphane, a major isothiocyanate derived from cruciferous vegetables, protects living systems against electrophile toxicity, oxidative stress, inflammation, and radiation. A major protective mechanism is the induction of a network of endogenous cytoprotective (phase 2) genes that are regulated by transcription factor Nrf2. To obtain a more detailed understanding of the anti-inflammatory and immunomodulatory effects of sulforaphane, we evaluated its effect on the phagocytosis activity of RAW 264.7 murine macrophage-like cells by measuring the uptake of 2-{mu}m diameter polystyrene beads. Sulforaphane raised the phagocytosis activity of RAW 264.7 cells but only in the absence or presence of low concentrations (1%) of fetal bovine serum. Higher serum concentrations depressed phagocytosis and abolished its stimulation by sulforaphane. This stimulation did not depend on the induction of Nrf2-regulated genes since it occurred in peritoneal macrophages of nrf2{sup -/-} mice. Moreover, a potent triterpenoid inducer of Nrf2-dependent genes did not stimulate phagocytosis, whereas sulforaphane and another isothiocyanate (benzyl isothiocyanate) had comparable inducer potencies. It has been shown recently that sulforaphane is a potent and direct inactivator of macrophage migration inhibitory factor (MIF), an inflammatory cytokine. Moreover, the addition of recombinant MIF to RAW 264.7 cells attenuated phagocytosis, but sulforaphane-inactivated MIF did not affect phagocytosis. The inactivation of MIF may therefore be involved in the phagocytosis-enhancing activity of sulforaphane.

  13. [Impacts of transcutaneous acupoint electric stimulation on the postoperative nausea and vomiting and plasma 5-HT concentration after cesarean section].

    Science.gov (United States)

    Liu, Yanli; Wang, Mingshan; Li, Qiujie; Wang, Ling; Li, Jingzhu

    2015-10-01

    To observe the effect of transcutaneous acupoint electric stimulation on the postoperative nausea and vomiting (PONV) and explore its mechanism. Ninety cases of elective cesarean section of I to II grade in American Society of Anesthesiologists (ASA) were collected and randomized into a transcutaneous acupoint electric stimulation group (group A), a sham-acupoint group (group B) and a blank control group (group C), 30 cases in each one. In the group A, 30 min before operation, the transcutaneous electric stimulation was applied to bilateral Neiguan (PC 6) and Zusanli (ST 36). The stimulation lasted during operation and 1 h after operation. In the group B, the same electric stimulation was given at the sites 3 cm lateral to the medial sides of Neiguan (PC 6) and Zusanli (ST 36). In the group C, the electric plaster was attached to bilateral Neiguan (PC 6) and Zusanli (ST 36), without any electric stimulation. The lumbar epidural combined anesthesia and the postoperative analgesia were same in each group. The mean arterial pressure (MAP), heart rate (HR) , oxygen saturation of blood (SpO2) and the VAS (visual analogue scale) score of nausea and vomiting were recorded before acupoint stimulation (T0), at skin incision (T1), fetal delivery (T2), abdominal exploration (T3) and 1 h after operation (T4) as well as bleeding and application of oxytocin, ephedrine and atropine during operation separately. The changes of plasma 5-hydroxytryptamine (5-HT) concentration were observed at T0 and 30 min after electric stimulation. The differences were not significant in MAP, HP and SpO2 at each time point of the three groups (all P> 0.05). The differences were not significant in bleeding and application of oxytocin, ephedrine and atropine during operation (all P > 0.05). The scores of nausea and vomiting in the group A during T1 to T4 were lower than those in the group B and group C (all P electric stimulation, plasma 5-HT concentration was lower than those in the group B and

  14. Ultrasound and nerve stimulator guided continuous femoral nerve block analgesia after total knee arthroplasty: a multicenter randomized controlled study

    Directory of Open Access Journals (Sweden)

    Fen Wang

    2015-02-01

    Full Text Available BACKGROUND AND OBJECTIVES: Postoperative analgesia is crucial for early functional excise after total knee arthroplasty. To investigate the clinical efficacy of ultrasound and nerve stimulator guided continuous femoral nerve block analgesia after total knee arthroplasty. METHODS: 46 patients with ASA grade I-III who underwent total knee arthroplasty received postoperative analgesia from October 2012 to January 2013. In 22 patients, ultrasound and nerve stimulator guided continuous femoral nerve block were performed for analgesia (CFNB group; in 24 patients, epidural analgesia was done (PCEA group. The analgesic effects, side effects, articular recovery and complications were compared between two groups. RESULTS: At 6 h and 12 h after surgery, the knee pain score (VAS score during functional tests after active exercise and after passive excise in CFNB were significantly reduced when compared with PCEA group. The amount of parecoxib used in CFNB patients was significantly reduced when compared with PCEA group. At 48 h after surgery, the muscle strength grade in CFNB group was significantly higher, and the time to ambulatory activity was shorter than those in PCEA group. The incidence of nausea and vomiting in CFNB patients was significantly reduced when compared with PCEA group. CONCLUSION: Ultrasound and nerve stimulator guided continuous femoral nerve block provide better analgesia at 6 h and 12 h, demonstrated by RVAS and PVAS. The amount of parecoxib also reduces, the incidence of nausea and vomiting decreased, the influence on muscle strength is compromised and patients can perform ambulatory activity under this condition.

  15. [Clinical observation on therapeutic effect of cupping combined with acupuncture stimulation at trigger points for lumbar myofascial pain syndrome].

    Science.gov (United States)

    Zhao, Hong

    2014-08-01

    To observe the clinical effect of cupping combined with acupuncture stimulation of trigger points on lumbar myofascial pain syndrome (MPS). Sixty MPS patients were randomly divided into acupuncture + TDP group (n = 30), and cupping + acupuncture group (n = 30). Patients in the acupuncture + TDP group were treated by acupuncture stimulation of trigger points and local TDP irradiation, and patients of the cupping + acupuncture group treated by intensive cupping applied to the myofascial band and acupuncture stimulation of the locus according to the position of muscular tension band. The therapeutic effects were assessed according to the score of the McGill pain questionnaire composing of pain rating index (PRI), visual analogue scale (VAS) and present pain intensity (PPI) before, immediately and 1 month after the treatment. After the treatment, the total effective rates of the acupuncture+ TDP and cupping + acupuncture groups were 83.3% (25/30) and 96.6% (29/30), respectively, without significant difference between the two groups (P > 0.05). One month's follow-up showed that the total effective rates of the acupuncture + TDP and cupping + acupuncture groups were 40.0% and 90.0% respectively, and the latter group was significantly better than the acupuncture + TDP group in the therapeutic effect (P cupping + acupuncture group were obviously lower than those of the acupuncture group (P cupping plus acupuncture can effectively relieve pain in MPS patients, while the therapeutic effect of cupping plus acupuncture treatment lasts longer analgesic effect.

  16. Problems of nuclear power facility vibroacoustic diagnostics

    Energy Technology Data Exchange (ETDEWEB)

    Ananiev, V.D. [Frank Lab. of Neutron Physics, Joint Inst. for Nuclear Research (FLNP, JINR), Dubna, Moscow (Russian Federation); Vinogradov, A.V. [Frank Lab. of Neutron Physics, Joint Inst. for Nuclear Research (FLNP, JINR), Dubna, Moscow (Russian Federation); Baranov, I.M. [The Russia Minatom Engineering Center of Nuclear Equipment Strength, Reliability and Lifetime (ECS MAE RDIPE), Moscow (Russian Federation); Syzarev, V.D. [The Russia Minatom Engineering Center of Nuclear Equipment Strength, Reliability and Lifetime (ECS MAE RDIPE), Moscow (Russian Federation); Menyailov, A.I. [Inst. for Problems in Mechanics, Russia Academy of Sciences (IPM RAS), Moscow (Russian Federation)

    1995-12-31

    Measurable vibrations and noise in reactor signals may, after proper processing, provide valuable information about the internal state of a reactor. A brief survey of certain algorithms for such processes is presented, including estiamtions of structure damping ratios; detection of restoring force non-linearity from the measured response of reactor elements and, as a result, finding the defect`s position; and location of the main sources of oscillation and vibration excitation. (orig.)

  17. Vibroacoustic response of an eccentric hollow cylinder

    Science.gov (United States)

    Hasheminejad, Seyyed M.; Mousavi-akbarzadeh, Hessam

    2012-07-01

    The linear 3D elasticity theory in conjunction with the classical method of separation of variables and the translational addition theorem for cylindrical wave functions are employed to investigate the three-dimensional steady-state sound radiation characteristics of an arbitrarily thick eccentric hollow cylinder of infinite length, submerged in an unbounded ideal acoustic medium, and subjected to arbitrary time-harmonic on-surface mechanical drives. The spatial Fourier transform along the shell axis and Fourier series expansion in the circumferential direction are utilized to obtain a formal integral expression for the radiated pressure field in the frequency domain. The method of stationary phase is subsequently implemented to evaluate the integral for an observation point in the far field. The analytical results are illustrated with numerical examples in which air-filled water-submerged concentric and eccentric steel cylinders are driven by harmonic concentrated radial and transverse surface loads. Effects of excitation and cylinder eccentricity on the far-field radiated pressure amplitudes/directivities are discussed and contributions from pseudo-Rayleigh, whispering gallery, and axially guided waves are examined through selected spatial dispersion patterns. Limiting cases are considered and the validity of results is established with the aid of a commercial finite element package as well as by comparison with the data in the existing literature.

  18. Vibroacoustic characteristics of a gothic harp.

    Science.gov (United States)

    Daltrop, Shira; Kotlicki, Andrzej; Waltham, Chris; Wolfe, Nathan; Elie, Benjamin; Gautier, François

    2012-01-01

    The "gothic" style of harp was popular across most of Europe from the late medieval period to the Renaissance. These harps have a one-piece, longitudinally oriented hardwood soundboard, as opposed to the transverse-oriented bonded softwood structure on a modern instrument. In addition, the one-piece back is flexible, whereas the back of a modern instrument is a rigid molded shell. To study the gothic harp, one was constructed from plans created by the Boston Museum of Fine Arts from a late German model in their collection. The vibrational behaviors of the soundboard and soundbox were measured at various stages of construction. The completed instrument was subjected to modal analysis and radiativity measurements. The sound radiation is dominated by two breathing modes at 188 and 273 Hz, each with strong motion of the back, and modes around 350 Hz. Taken together, these modes function like the A0/T1 resonance pairs seen in the soundboxes of other instruments, and a comparison is made with the guitar. Also observed is that as the frequency increases, radiation is emitted from higher up the soundboard, and from higher soundholes. This feature has been observed in other harps, and is a consequence of the harp family's unique geometry. © 2012 Acoustical Society of America.

  19. Foundation of statistical energy analysis in vibroacoustics

    CERN Document Server

    Le Bot, A

    2015-01-01

    This title deals with the statistical theory of sound and vibration. The foundation of statistical energy analysis is presented in great detail. In the modal approach, an introduction to random vibration with application to complex systems having a large number of modes is provided. For the wave approach, the phenomena of propagation, group speed, and energy transport are extensively discussed. Particular emphasis is given to the emergence of diffuse field, the central concept of the theory.

  20. Abnormal respiratory drive in vibroacoustic disease

    Directory of Open Access Journals (Sweden)

    José Reis Ferreira

    2006-07-01

    Full Text Available Introduction: Central nervous system disorders in workers exposed to low frequency noise (LFN, 60%. Discussion: In the involuntary response to increased PCO2 levels, central chemoreceptors are responsible for 70% of the ventilatory stimulus. In VAD patients, this dysfunction may originate in the brainstem. This is corroborated by the fact that VAD patients register abnormal values for auditory brainstem evoked potentials, and disclose lesions with magnetic resonance imaging. The neurological control of breathing is compromised in VAD patients. The P0.1(CO2 index may be a useful clinical indicator for VAD diagnosis and follow-up. Resumo: Enquadramento: As alterações do sistema nervoso central em trabalhadores expostos a ruído de baixa frequência (RBF, 60%. Conclusões: Na resposta reflexa ao acréscimo de PCO2, os quimio-receptores centrais são responsáveis por 70% do estímulo ventilatório. Um estímulo ventilatório diminuído pode traduzir certa disfunção do tronco cerebral. Em doentes com VAD, esta disfunção é corroborada por anomalias dos potenciais evocados auditivos do tronco cerebral, bem como por alterações detectáveis em ressonância magnética. O índice P0.1CO2 pode revelar-se um indicador clínico útil para o diagnóstico e seguimento da VAD. Em resumo, o controlo neurológico da respiração está comprometido em doentes com VAD. Key-words: Low frequency noise, infrasound, respiratory control, P0.1CO2, peak respiratory pressure, Palavras-chave: Ruído de baixa frequência, infra-sons, controlo da respiração, P0.1CO2, pressões respiratórias máximas

  1. Acupuncture Treatment for Low Back Pain and Lower Limb Symptoms—The Relation between Acupuncture or Electroacupuncture Stimulation and Sciatic Nerve Blood Flow

    Directory of Open Access Journals (Sweden)

    Motohiro Inoue

    2008-01-01

    Full Text Available To investigate the clinical efficacy of acupuncture treatment for lumbar spinal canal stenosis and herniated lumbar disc and to clarify the mechanisms in an animal experiment that evaluated acupuncture on sciatic nerve blood flow. In the clinical trial, patients with lumbar spinal canal stenosis or herniated lumbar disc were divided into three treatment groups; (i Ex-B2 (at the disordered level, (ii electrical acupuncture (EA on the pudendal nerve and (iii EA at the nerve root. Primary outcome measurements were pain and dysesthesia [evaluated with a visual analogue scale (VAS] and continuous walking distance. In the animal study, sciatic nerve blood flow was measured with laser-Doppler flowmetry at, before and during three kinds of stimulation (manual acupuncture on lumber muscle, electrical stimulation on the pudendal nerve and electrical stimulation on the sciatic nerve in anesthetized rats. For the clinical trial, approximately half of the patients who received Ex-B2 revealed amelioration of the symptoms. EA on the pudendal nerve was effective for the symptoms which had not improved by Ex-B2. Considerable immediate and sustained relief was observed in patients who received EA at the nerve root. For the animal study, increase in sciatic nerve blood flow was observed in 56.9% of the trial with lumber muscle acupuncture, 100% with pudendal nerve stimulation and 100% with sciatic nerve stimulation. Sciatic nerve stimulation sustained the increase longer than pudendal nerve stimulation. One mechanism of action of acupuncture and electrical acupuncture stimulation could be that, in addition to its influence on the pain inhibitory system, it participates in causing a transient change in sciatic nerve blood blow, including circulation to the cauda equine and nerve root.

  2. Stimulating parameters and de-synchronization in vagus nerve stimulation therapy for epilepsy

    Science.gov (United States)

    Li, Y.-L.; Chen, Z.-Y.; Ma, J.; Feng, W.-J.

    2008-02-01

    The influence of the stimulation parameters on the de-synchronization of small world Hindmarsh-Rose (H-R) neural network is numerically investigated in the vagus nerve stimulation therapy for epilepsy. The simulation shows that synchronization evolves into de-synchronization when a part of neurons (about 10 percent) is stimulated with a pulse current signal. The network de-synchronization appears to be sensitive to the stimulation parameters. For the case of the same stimulation intensity, those weakly coupled networks reach de-synchronization more easily than strongly coupled networks. There exist an optimal stimulation interval and period of continuous stimulation time when other stimulation parameters remain invariable.

  3. Stimulating parameters and de-synchronization in vagus nerve stimulation therapy for epilepsy

    Energy Technology Data Exchange (ETDEWEB)

    Li, Y-L; Ma, J; Feng, W-J [Institute of Theoretical Physics, Lanzhou University of Technology, 287 Langongping Road, Lanzhou 730050 (China); Chen, Z-Y [Department of Mechanical Engineering, University of California at Berkeley, Berkeley, CA 94720 (United States)], E-mail: hyperchaos@163.com, E-mail: liyl20031@126.com, E-mail: chen_zhao_yang@yahoo.com

    2008-02-15

    The influence of the stimulation parameters on the de-synchronization of small world Hindmarsh-Rose (H-R) neural network is numerically investigated in the vagus nerve stimulation therapy for epilepsy. The simulation shows that synchronization evolves into de-synchronization when a part of neurons (about 10 percent) is stimulated with a pulse current signal. The network de-synchronization appears to be sensitive to the stimulation parameters. For the case of the same stimulation intensity, those weakly coupled networks reach de-synchronization more easily than strongly coupled networks. There exist an optimal stimulation interval and period of continuous stimulation time when other stimulation parameters remain invariable.

  4. Anaesthesia and deep brain stimulation

    Directory of Open Access Journals (Sweden)

    Barkha Bindu

    2016-01-01

    Full Text Available Deep brain stimulation (DBS is becoming an increasingly popular minimally invasive surgical procedure for various movement disorders, especially Parkinson′s disease. Different nuclei have been identified depending on patients′ symptoms, but the success or failure of the procedure depends on various other factors such as proper patient selection and risk-benefit analysis. While various techniques of anaesthesia including monitored anaesthesia care, conscious sedation and general anaesthesia are being used routinely, no clear-cut evidence exists as to the best technique for this procedure. This review article discusses the surgical procedure of DBS, devices currently available, perioperative anaesthetic concerns and techniques, effect of anaesthetic drugs on microelectrode recordings and macro-stimulation and associated complications.

  5. Introduction to Deep Brain Stimulation.

    Science.gov (United States)

    Lozano, Andres M; Gross, Robert E

    2017-04-01

    It is estimated that over 160,000 patients worldwide have received deep brain stimulation (DBS) to date predominantly for Parkinson's disease and other movement disorders. With the success of this therapy, a greater appreciation of the clinical benefits and adverse effects is being realized. Neurosurgeons are increasingly paying attention to the technical details of these procedures and optimizing targeting, surgical techniques, and programming to improve outcomes. In this issue, the nuances of surgical techniques for DBS are covered by Dr. House. Dr. Toda et al. and Mr. Chartrain et al. tackle the approach to treating tremors, either essential tremor or Holmes tremor, using either a single target or, in cases of difficult-to-treat tremors, using more than one target and interleaving the stimulation. These abstracts and videos will be appreciated by both those who are being initiated to DBS and the more seasoned practitioners who are looking for helpful hints to tackle challenging cases.

  6. Nerve Stimulator Guided Axillary Block in Painless Reduction of Distal Radius Fractures; a Randomized Clinical Trial

    Directory of Open Access Journals (Sweden)

    Hossein Alimohammadi

    2013-12-01

    Full Text Available Introduction: Given the high prevalence of upper extremity fractures and increasing need to perform painless reduction in the emergency departments, the use of analgesic methods with fewer complications and more satisfaction appears to be essential. The aim of this study is comparison the nerve stimulator guided axillary block (NSAB with intravenous sedation in induction of analgesia for painless reduction of distal radius fractures. Methods: In the present randomized clinical trial, 60 patients (18-70 years of age suffered from distal radius fractures, were divided into two equal groups. One group received axillary nerve block by nerve stimulator guidance and the other procedural sedation and analgesia (PSA using midazolam/fentanyl. Onset of analgesia, duration of analgesic effect, total procedure time and pain scores were recorded using visual analogue scale (VAS and the outcomes were compared. Chi-squared and student t test were performed to evaluate differences between two groups. Results: Sixty patients were randomly divided into two groups (83.3% male. The mean age of patients was 31 ±0.7 years. While the onset of analgesia was significantly longer in the NSAB group, the mean total time of procedure was shorter than PSA (p<0.001. The NSAB group needed a shorter post-operative observation time (P<0.001. Both groups experienced equal pain relief before, during and after procedure (p>0.05. Conclusion: It seems that shorter post-operative monitoring time and consequently lesser total time of procedure, make nerve stimulator guided axillary block as an appropriate alternative for procedural sedation and analgesia in painless reduction of distal radius fractures in emergency department. 

  7. Transcranial Magnetic Stimulation in Children

    OpenAIRE

    Garvey, Marjorie A.; Mall, Volker

    2008-01-01

    Developmental disabilities (e.g. attention deficit disorder; cerebral palsy) are frequently associated with deviations of the typical pattern of motor skill maturation. Neurophysiologic tools, such as transcranial magnetic stimulation (TMS), which probe motor cortex function, can potentially provide insights into both typical neuromotor maturation and the mechanisms underlying the motor skill deficits in children with developmental disabilities. These insights may set the stage for finding ef...

  8. Cushing, Penfield, and cortical stimulation.

    Science.gov (United States)

    Leblanc, Richard

    2018-01-26

    Harvey Cushing and Wilder Penfield enjoyed a unique professional and personal relationship. Shortly before his retirement from Harvard University in 1933, Cushing sent Penfield 8 sketches that he drew in 1902 and 1903 while he was at Johns Hopkins Hospital. The first series of 3 sketches illustrate the relationship between a cortical hemorrhagic lesion and the motor strip in a patient with focal motor seizures. The second series also comprises 3 sketches. These depict the operative findings in a patient in whom Cushing had electrically stimulated the precentral gyrus, before resecting the cortex subserving motility of the upper extremity to control painful dyskinetic movements. The third series consists of 2 sketches that illustrate the results of stimulation of the motor strip as an aid in the safe resection of an epileptogenic focus in a patient with Jacksonian seizures. These sketches are the subjects of this paper. They add to the relatively sparse record of Cushing's activities in cortical stimulation and in the treatment of functional disorders.

  9. Cortical stimulation and neuropathic pain

    Directory of Open Access Journals (Sweden)

    Cristiane Cagnoni Ramos

    2015-05-01

    Full Text Available This paper is a review of physiological and behavioral data on motor cortex stimulation (MCS and its role in persistent neuropathic pain. MCS has been widely used in clinical medicine as a tool for the management of pain that does not respond satisfactorily to any kind of conventional analgesia. Some important mechanisms involved in nociceptive modulation still remains unclear. The aim of this study was to describe the mechanisms involved in neuropathic pain and introduce the effectiveness of electrical stimulation of the motor cortex used in the treatment of this disease. The ascending pain pathways are activated by peripheral receptors, in which there is the transduction of a chemical, physical or mechanical stimulus as a nerve impulse, where this impulse is transmitted to the dorsal horn of the spinal cord, which connects with second-order neurons and ascends to different locations in the central nervous system where the stimulus is perceived as pain. Because MCS has been proved to modulate this pathway in the motor cortex, it has been studied to mimic its effects in clinical practice and improve the treatments used for chronic pain. MCS has gained much attention in recent years due to its action in reversing chronic neuropathic pain, this being more effective than electrical stimulation at different locations and related pain nuclei.

  10. Cortical stimulation and neuropathic pain

    Directory of Open Access Journals (Sweden)

    Cristiane Cagnoni Ramos

    2015-02-01

    Full Text Available http://dx.doi.org/10.5007/2175-7925.2015v28n2p1 This paper is a review of physiological and behavioral data on motor cortex stimulation (MCS and its role in persistent neuropathic pain. MCS has been widely used in clinical medicine as a tool for the management of pain that does not respond satisfactorily to any kind of conventional analgesia. Some important mechanisms involved in nociceptive modulation still remains unclear. The aim of this study was to describe the mechanisms involved in neuropathic pain and introduce the effectiveness of electrical stimulation of the motor cortex used in the treatment of this disease. The ascending pain pathways are activated by peripheral receptors, in which there is the transduction of a chemical, physical or mechanical stimulus as a nerve impulse, where this impulse is transmitted to the dorsal horn of the spinal cord, which connects with second-order neurons and ascends to different locations in the central nervous system where the stimulus is perceived as pain. Because MCS has been proved to modulate this pathway in the motor cortex, it has been studied to mimic its effects in clinical practice and improve the treatments used for chronic pain. MCS has gained much attention in recent years due to its action in reversing chronic neuropathic pain, this being more effective than electrical stimulation at different locations and related pain nuclei.

  11. Performance Enhancement by Brain Stimulation

    Directory of Open Access Journals (Sweden)

    Parisa Gazerani

    2017-09-01

    Full Text Available Number of substances and strategies are available to increase performance in sport (Catlin and Murray, 1996. Since 2004, the World Anti-Doping Agency (WADA posts an updated list of substances and methods prohibited to athletes. Drugs (e.g., steroids, stimulants are a major part of this list; however, technologies and methods (e.g., gene doping are increasingly being identified and added (WADA, 2017. Among technologies and methods that might exert a potential effect on athletic performance, brain stimulation has recently been subjected to extensive discussion. Neuro-enhancement for doping purposes has been termed “neurodoping” in the literature (Davis, 2013; however, this concept needs further documentation before the term “neurodoping” can be used properly. Two major non-invasive techniques of brain stimulations are transcranial magnetic stimulation (TMS (Hallett, 2007; Rossi et al., 2009, and transcranial direct current stimulation (tDCS (Stagg and Nitsche, 2011. In TMS, an electric coil held over the head applies magnetic pulses to create currents in the brain. In tDCS, a low, continuous electrical current is delivered to the brain by using surface electrodes attached on the scalp. TMS and tDCS have been used in both research and clinic (Shin and Pelled, 2017 for example to examine alterations in cognitive function or motor skills or to assist in recovering motor function after a stroke (Gomez Palacio Schjetnan et al., 2013 or reducing fatigue in patients with multiple sclerosis (Saiote et al., 2014. In an opinion paper, it was proposed that use of emerging brain stimulation techniques might also enhance physical and mental performance in sports (Davis, 2013. The assumption was based on several reports. For example some studies have shown that TMS could shorten reaction times to visual, auditory and touch stimuli, reduce tremor, and enhance the acquisition of complex motor skills. Based on the current evidence, a recent review (Colzato

  12. Gastric stimulation for weight loss

    Science.gov (United States)

    Mizrahi, Meir; Ben Ya'acov, Ami; Ilan, Yaron

    2012-01-01

    The prevalence of obesity is growing to epidemic proportions, and there is clearly a need for minimally invasive therapies with few adverse effects that allow for sustained weight loss. Behavior and lifestyle therapy are safe treatments for obesity in the short term, but the durability of the weight loss is limited. Although promising obesity drugs are in development, the currently available drugs lack efficacy or have unacceptable side effects. Surgery leads to long-term weight loss, but it is associated with morbidity and mortality. Gastric electrical stimulation (GES) has received increasing attention as a potential tool for treating obesity and gastrointestinal dysmotility disorders. GES is a promising, minimally invasive, safe, and effective method for treating obesity. External gastric pacing is aimed at alteration of the motility of the gastrointestinal tract in a way that will alter absorption due to alteration of transit time. In addition, data from animal models and preliminary data from human trials suggest a role for the gut-brain axis in the mechanism of GES. This may involve alteration of secretion of hormones associated with hunger or satiety. Patient selection for gastric stimulation therapy seems to be an important determinant of the treatment’s outcome. Here, we review the current status, potential mechanisms of action, and possible future applications of gastric stimulation for obesity. PMID:22654422

  13. Vagus Nerve Stimulation for Treating Epilepsy

    Science.gov (United States)

    ... and their FAMILIES VAGUS NERVE STIMULATION FOR TREATING EPILEPSY This information sheet is provided to help you ... how vagus nerve stimulation (VNS) may help treat epilepsy. The American Academy of Neurology (AAN) is the ...

  14. [Clinical Trials for Treatment of Acute Lumbar Sprain by Acupuncture Stimulation of "Yaotong" and Local Ashi-points in Combination with Patients' Lumbar Movement].

    Science.gov (United States)

    Liu, Li-Li; Lu, Jing; Ma, Hui-Fang

    2017-02-25

    To observe the clinical effect of acupuncture stimulation of "Yaotong"-point (one acupoint of balance acupuncture therapy) and Ashi-points combined with patients' lumbar movement in the treatment of acute lumbar sprain. Forty-six acute lumbar sprain patients were randomized into treatment group (26 cases) and control group (20 cases) using a random number table. The patients of the treatment group were treated by acupuncture stimulation of "Yaotong"-point[above Yintang (EX-HN 3)] and local Ashi-points for 20 min, and were asked to move the waist simultaneously during acupuncture stimulation. The treatment was conducted once every other day, 3 times a week, one week in total. Those of the control group were treated by oral administration of loxoprofen sodium tablets (60 mg, twice a day, for one week). The pain severity of lumbago and motor function were assessed by using visual analogue scale(VAS) and present pain intensity(PPI)and lumbar range of motion(ROM) separately. Following the treatment, of the 20 and 26 acute lumbar sprain patients in the control and treatment groups, 6(30.0%)and 14(53.8%)were cured, 9 (45.0%) and 11 (42.4%) experienced an improvement in their symptoms, 5 (25.0%) and 1 (3.8%) was invalid, with the effective rates being 75.0% and 96.2%, respectively. Compared with pre-treatment, the ROM and VAS scores were significantly decreased in both the control and treatment groups post-treatment (Plumbar motion function and in pain relief (Plumbar movement is effective in reducing lumbar pain and improving lumbar motor function in the treatment of acute lumbar sprain.

  15. Neuro magnetic stimulation: Engineering aspects

    Science.gov (United States)

    Al-Mutawaly, Nafia

    Magnetic nerve stimulation has proven to be an effective, non-invasive technique to excite peripheral and central nervous systems. In this technique, the excitement of the neural tissue depends on exposure to a transient magnetic field generated by passing a high pulse of current through a coil. By positioning the coil in a specific orientation over the targeted tissue, the transient magnetic field will induce an electric field in the conductive milieu of the body. If this field reaches a certain threshold within a specific time period, neural depolarization is then evident. The primary objective of this thesis is the development and testing of new coil designs that can focus the magnetic field more effectively. Two such coils have been built. The first coil has an air core, while the other has a magnetic core. The magnetic fields of these coils, applied to the human upper limb, have been determined theoretically, and the results compared to the field generated by the most common commercial coil, the Figure-8 coil. To design these coils and to test them experimentally, a current pulse generator has been designed and built. Further, a novel measurement system using surface mount inductances and a computer based data acquisition system has been designed and built. The experimental results confirm the theoretical findings, that the air core coil is slightly better than the Figure-8, as far as field strength and focality are concerned. In addition, the experimental results, prove that the coil with the ferromagnetic core, is superior. The second objective is to investigate the effect of stimulus waveforms theoretically, experimentally, and through in vivo study. The goals of the study are to establish a quantitative relationship among various waveforms and to investigate the effect of these waveforms in determining the site of stimulation. Accordingly, a multi subject trial was conducted: a Figure-8 coil was applied to the median nerve of ten subjects at the upper limb

  16. Optical stimulator for vision-based sensors

    DEFF Research Database (Denmark)

    Rössler, Dirk; Pedersen, David Arge Klevang; Benn, Mathias

    2014-01-01

    We have developed an optical stimulator system for vision-based sensors. The stimulator is an efficient tool for stimulating a camera during on-ground testing with scenes representative of spacecraft flights. Such scenes include starry sky, planetary objects, and other spacecraft. The optical...

  17. Bubble stimulation efficiency of dinoflagellate bioluminescence.

    Science.gov (United States)

    Deane, Grant B; Stokes, M Dale; Latz, Michael I

    2016-02-01

    Dinoflagellate bioluminescence, a common source of bioluminescence in coastal waters, is stimulated by flow agitation. Although bubbles are anecdotally known to be stimulatory, the process has never been experimentally investigated. This study quantified the flash response of the bioluminescent dinoflagellate Lingulodinium polyedrum to stimulation by bubbles rising through still seawater. Cells were stimulated by isolated bubbles of 0.3-3 mm radii rising at their terminal velocity, and also by bubble clouds containing bubbles of 0.06-10 mm radii for different air flow rates. Stimulation efficiency, the proportion of cells producing a flash within the volume of water swept out by a rising bubble, decreased with decreasing bubble radius for radii less than approximately 1 mm. Bubbles smaller than a critical radius in the range 0.275-0.325 mm did not stimulate a flash response. The fraction of cells stimulated by bubble clouds was proportional to the volume of air in the bubble cloud, with lower stimulation levels observed for clouds with smaller bubbles. An empirical model for bubble cloud stimulation based on the isolated bubble observations successfully reproduced the observed stimulation by bubble clouds for low air flow rates. High air flow rates stimulated more light emission than expected, presumably because of additional fluid shear stress associated with collective buoyancy effects generated by the high air fraction bubble cloud. These results are relevant to bioluminescence stimulation by bubbles in two-phase flows, such as in ship wakes, breaking waves, and sparged bioreactors. Copyright © 2015 John Wiley & Sons, Ltd.

  18. Comparison of the Effects of Transcutaneous Electrical Nerve Stimulation and Low-Level Laser Therapy on Drug-Resistant Temporomandibular Disorders.

    Science.gov (United States)

    Rezazadeh, Fahimeh; Hajian, Khadijeh; Shahidi, Shoaleh; Piroozi, Soraya

    2017-09-01

    Temporomandibular disorder (TMD) is a clinical term used for clinical signs and symptoms that affect the temporomandibular joints, masticatory muscles, and associated structures. Surgical and non-surgical treatments can be used for management of TMD. Non-surgical route is the main part of the treatment, since clinicians prefer non-aggressive treatment for TMD such as pharmacological and physical therapy. Low-level laser therapy (LLLT) and transcutaneous electrical nerve stimulation (TENS) are the main procedures in physical therapy. The aim of this study was to evaluate the effectiveness of TENS and LLLT in treatment of TMD patients who did not respond to pharmacological therapy. This clinical trial was performed on 45 patients who randomly received either TENS or LLLT for 8 sessions. LLLT was applied with diode laser (Ga-Al-As, 980nm, dose 5j/cm(2)) and TENS by using two carbon electrodes with 75 Hz frequency (0.75 msec pulse width). Helkimo index and visual analogue scale (VAS) were measured during the treatment period and throughout the follow-up sessions. Significant reduction in the VAS and Helkimo index was observed in both TENS and LLLT group. There was no significant difference between the two methods during the treatment; however, TENS was more effective in pain reduction in follow-ups. This study justified the use of TENS therapy as well as LLLT in drug-resistant TMD. Both were useful in relieving the pain and muscles tenderness, although, TENS was more effective than LLLT.

  19. The use of transcutaneous electrical nerve stimulation (TENS) in a major cancer center for the treatment of severe cancer-related pain and associated disability.

    Science.gov (United States)

    Loh, Jeffrey; Gulati, Amitabh

    2015-06-01

    Cancer pain is difficult to treat, often requiring a multimodal approach. While medication management remains the mainstay for the treatment of cancer pain, medications are often associated with undesired side effects. Transcutaneous electrical nerve stimulation (TENS) provides a potential adjunctive method for treating cancer pain with minimal side effects. Few studies have been performed evaluating the efficacy of TENS on cancer pain. We sought to examine the usefulness of TENS on all cancer patients and to specifically look at the use of TENS as a goal-directed therapy to improve functionality. Retrospective cohort study. Since 2008, patients with chronic cancer pain and on multimodal pain regimens were trialed with TENS. Those patients who showed an improvement in pain symptoms or severity were educated about and provided with a TENS unit for use at home. Pain symptoms and scores were monitored with the visual analog scale (VAS), the numerical rating pain (NRP) scale, and Short-Form McGill Questionnaire at the start of TENS treatment and at 2 months follow-up. TENS proved beneficial in 69.7% of patients over the course of 2 months. In TENS responsive patients, VAS scores decreased by 9.8 on a 0-100 mm scale (P TENS provides a beneficial adjunct for the treatment of cancer pain, especially when utilized as a goal-directed therapy. Wiley Periodicals, Inc.

  20. Treatment of knee osteoarthritis with platelet-rich plasma in comparison with transcutaneous electrical nerve stimulation plus exercise: a randomized clinical trial.

    Science.gov (United States)

    Angoorani, Hooman; Mazaherinezhad, Ali; Marjomaki, Omid; Younespour, Shima

    2015-01-01

    Osteoarthritis is a disabling musculoskeletal disease with no definite treatment. This study compared the effect of Platelet-rich plasma (PRP) and Transcutaneous Electrical Nerve Stimulation (TENS) plus exercise in the treatment of patients with knee joint osteoarthritis. 54 eligible patients with knee osteoarthritis were randomly allocated into two groups. (IRCT2012110611382N) Group A (27 patients) received 2 injections of PRP (4 weeks apart) and group B (27 patients) received 10 sessions of TENS as well as exercise during the study period. Clinical outcome was evaluated using the Knee injury and Osteoarthritis Outcome Scores (KOOS) questionnaire before the treatment, 4 weeks, and 8 weeks after that the treatment. Pain was also assessed using a visual analog scale (VAS). Time to an intolerable knee pain during treadmill workout was also evaluated using an objective test. In the PRP group, the mean KOOS symptom score improved significantly from baseline to the end of study, while the change was not significant over this period for the group B. In both groups, significant reductions were observed in VAS scores from baseline till the end of study. The mean time to feel intolerable knee pain during treadmill work out of PRP group increased significantly from baseline to week 4, but no significant changes were found in this parameter over the time of study in the group B. Intraarticular injection of PRP is an effective, safe method for short-term treatment of patients with knee joint osteoarthritis.

  1. Transcutaneous electrical nerve stimulation (TENS) for fibromyalgia in adults.

    Science.gov (United States)

    Johnson, Mark I; Claydon, Leica S; Herbison, G Peter; Jones, Gareth; Paley, Carole A

    2017-10-09

    Fibromyalgia is characterised by persistent, widespread pain; sleep problems; and fatigue. Transcutaneous electrical nerve stimulation (TENS) is the delivery of pulsed electrical currents across the intact surface of the skin to stimulate peripheral nerves and is used extensively to manage painful conditions. TENS is inexpensive, safe, and can be self-administered. TENS reduces pain during movement in some people so it may be a useful adjunct to assist participation in exercise and activities of daily living. To date, there has been only one systematic review in 2012 which included TENS, amongst other treatments, for fibromyalgia, and the authors concluded that TENS was not effective. To assess the analgesic efficacy and adverse events of TENS alone or added to usual care (including exercise) compared with placebo (sham) TENS; no treatment; exercise alone; or other treatment including medication, electroacupuncture, warmth therapy, or hydrotherapy for fibromyalgia in adults. We searched the following electronic databases up to 18 January 2017: CENTRAL (CRSO); MEDLINE (Ovid); Embase (Ovid); CINAHL (EBSCO); PsycINFO (Ovid); LILACS; PEDRO; Web of Science (ISI); AMED (Ovid); and SPORTDiscus (EBSCO). We also searched three trial registries. There were no language restrictions. We included randomised controlled trials (RCTs) or quasi-randomised trials of TENS treatment for pain associated with fibromyalgia in adults. We included cross-over and parallel-group trial designs. We included studies that evaluated TENS administered using non-invasive techniques at intensities that produced perceptible TENS sensations during stimulation at either the site of pain or over nerve bundles proximal (or near) to the site of pain. We included TENS administered as a sole treatment or TENS in combination with other treatments, and TENS given as a single treatment or as a course of treatments. Two review authors independently determined study eligibility by assessing each record and

  2. Braille line using electrical stimulation

    Energy Technology Data Exchange (ETDEWEB)

    Puertas, A; Pures, P; Echenique, A M; Ensinck, J P Graffigna y G [Gabinete de TecnologIa Medica. Universidad N. de San Juan (Argentina)

    2007-11-15

    Conceived within the field of Rehabilitation Technologies for visually impaired persons, the present work aims at enabling the blind user to read written material by means of a tactile display. Once he is familiarized to operate this system, the user will be able to achieve greater performance in study, academic and job activities, thus achieving a rapid and easier social inclusion. The devise accepts any kind of text that is computer-loadable (documents, books, Internet information, and the like) which, through digital means, can be read as Braille text on the pad. This tactile display is composed of an electrodes platform that simulate, through stimulation the writing/reading Braille characters. In order to perceive said characters in similar way to the tactile feeling from paper material, the skin receptor of fingers are stimulated electrically so as to simulate the same pressure and depressions as those of the paper-based counterpart information. Once designed and developed, the display was tested with blind subjects, with relatively satisfactory results. As a continuing project, this prototype is currently being improved as regards.

  3. Braille line using electrical stimulation

    Science.gov (United States)

    Puertas, A.; Purés, P.; Echenique, A. M.; Ensinck, J. P. Graffigna y. G.

    2007-11-01

    Conceived within the field of Rehabilitation Technologies for visually impaired persons, the present work aims at enabling the blind user to read written material by means of a tactile display. Once he is familiarized to operate this system, the user will be able to achieve greater performance in study, academic and job activities, thus achieving a rapid and easier social inclusion. The devise accepts any kind of text that is computer-loadable (documents, books, Internet information, and the like) which, through digital means, can be read as Braille text on the pad. This tactile display is composed of an electrodes platform that simulate, through stimulation the writing/reading Braille characters. In order to perceive said characters in similar way to the tactile feeling from paper material, the skin receptor of fingers are stimulated electrically so as to simulate the same pressure and depressions as those of the paper-based counterpart information. Once designed and developed, the display was tested with blind subjects, with relatively satisfactory results. As a continuing project, this prototype is currently being improved as regards.

  4. Mirror Therapy and Transcutaneous Electrical Nerve Stimulation for Management of Phantom Limb Pain in Amputees - A Single Blinded Randomized Controlled Trial.

    Science.gov (United States)

    Tilak, Merlyn; Isaac, Serin Anna; Fletcher, Jebaraj; Vasanthan, Lenny Thinagaran; Subbaiah, Rajalakshmi Sankaran; Babu, Andrew; Bhide, Rohit; Tharion, George

    2016-06-01

    Phantom limb pain (PLP) can be disabling for nearly two thirds of amputees. Hence, there is a need to find an effective and inexpensive treatment that can be self administered. Among the non-pharmacological treatment for PLP, transcutaneous electrical nerve stimulation (TENS) applied to the contralateral extremity and mirror therapy are two promising options. However, there are no studies to compare the two treatments. The purpose of this study is to evaluate and compare mirror therapy and TENS in the management of PLP in subjects with amputation. The study was an assessor blinded randomized controlled trial conducted at Physiotherapy Gymnasium of Physical Medicine and Rehabilitation Department, Christian Medical College, Vellore. Twenty-six subjects with PLP consented to participate. An initial assessment of pain using visual analogue scale (VAS) and universal pain score (UPS) was performed by a therapist blinded to the treatment given. Random allocation into Group I-mirror therapy and Group II-TENS was carried out. After 4 days of treatment, pain was re-assessed by the same therapist. The mean difference in Pre and Post values were compared among the groups. The change in pre-post score was analyzed using the paired t test. Participants of Group I had significant decrease in pain [VAS ( p = 0.003) and UPS ( p = 0.001)]. Group II also showed a significant reduction in pain [VAS ( p = 0.003) and UPS ( p = 0.002)]. However, no difference was observed between the two groups [VAS ( p = 0.223 and UPS ( p = 0.956)]. Both Mirror Therapy and TENS were found to be effective in pain reduction on a short-term basis. However, no difference between the two groups was found. Substantiation with long-term follow-up is essential to find its long-term effectiveness. Copyright © 2015 John Wiley & Sons, Ltd. Copyright © 2015 John Wiley & Sons, Ltd.

  5. VAGUS NERVE STIMULATION REGULATES HEMOSTASIS IN SWINE

    Science.gov (United States)

    Czura, Christopher J.; Schultz, Arthur; Kaipel, Martin; Khadem, Anna; Huston, Jared M.; Pavlov, Valentin A.; Redl, Heinz; Tracey, Kevin J.

    2010-01-01

    The central nervous system regulates peripheral immune responses via the vagus nerve, the primary neural component of the cholinergic anti-inflammatory pathway. Electrical stimulation of the vagus nerve suppresses pro-inflammatory cytokine release in response to endotoxin, I/R injury, and hypovolemic shock and protects against lethal hypotension. To determine the effect of vagus nerve stimulation on coagulation pathways, anesthetized pigs were subjected to partial ear resection before and after electrical vagus nerve stimulation. We observed that electrical vagus nerve stimulation significantly decreased bleeding time (pre–electrical vagus nerve stimulation = 1033 ± 210 s versus post–electrical vagus nerve stimulation = 585 ± 111 s; P vagus nerve stimulation = 48.4 ± 6.8 mL versus post–electrical vagus nerve stimulation = 26.3 ± 6.7 mL; P vagus nerve stimulation was independent of changes in heart rate or blood pressure and correlated with increased thrombin/antithrombin III complex generation in shed blood. These data indicate that electrical stimulation of the vagus nerve attenuates peripheral hemorrhage in a porcine model of soft tissue injury and that this protective effect is associated with increased coagulation factor activity. PMID:19953009

  6. Effect of cathodal high-voltage electrical stimulation on pain in women with TMD.

    Science.gov (United States)

    Gomes, Natalia C M C; Berni-Schwarzenbeck, Kelly C S; Packer, Amanda C; Rdrigues-Bigaton, Delaine

    2012-01-01

    Pain is the main symptom of patients with temporomandibular disorder (TMD). To evaluate the effect of cathodal high-voltage electrical stimulation (HVES) on pain intensity in women with TMD. Twenty women with TMD (24.25 ± 8.90 years old) participated in the study. They were divided into experimental group (EG, n=10), which received 10 applications of HVES, and placebo group (PG, n=10), which received sham treatment with disconnected HVES equipment. For the sample selection, we used the Research Diagnostic Criteria for Temporomandibular Disorder (RDC/TMD). Pain level was evaluated using a visual analog scale (VAS) applied prior to and after the tenth application of HVES. Data were analyzed using the Wilcoxon signed-rank test and the Mann-Whitney test. Ten applications of HVES reduced pain intensity in the EG (p=0.01). In the PG, there was no significant difference (p=0.20). After the application of HVES, no difference was found (p=0.65) between the groups. The cathodal HVES was effective in reducing pain in women with TMD. Trial Registration RBR-4bk94x.

  7. A Meta-Analysis of Transcutaneous Electrical Nerve Stimulation for Chronic Low Back Pain.

    Science.gov (United States)

    Jauregui, Julio J; Cherian, Jeffrey J; Gwam, Chukwuweike U; Chughtai, Morad; Mistry, Jaydev B; Elmallah, Randa K; Harwin, Steven F; Bhave, Anil; Mont, Michael A

    2016-04-01

    Transcutaneous electrical nerve stimulation (TENS) may provide a safe alternative to current side-effect-heavy narcotics and anti-inflammatories utilized in chronic low back pain. Therefore, we performed a meta-analysis to evaluate the efficacy of TENS for the treatment of chronic low back pain. We included randomized controlled trials (RCTs), cohort studies, and randomized crossover studies on TENS for the management of low back pain. We utilized a visual analogue scale (VAS) for pain as our primary outcome. Effectiveness of treatment was quantified using improvement in outcome scores for each study. Of the studies that met the criteria, 13 allowed for calculation of weighted mean differences in pain reduction. We used a random model effect to evaluate changes in pain produced by the intervention. Included were nine level I and four level II, encompassing 267 patients (39% male) who had a mean follow-up of seven weeks (range; 2 to 24 weeks). The mean duration of treatment was six weeks (range; 2 to 24 weeks). The standardized mean difference in pain from pre- to post-treatment for TENS was 0.844, which demonstrated significant improvement of TENS on pain reduction. When subdividing treatment duration, patients that were treated for 5 weeks did not. Treatment of chronic low back pain with TENS demonstrated significant pain reduction. The application of TENS may lead to less pain medication usage and should be incorporated into the treatment armamentarium for chronic low back pain.

  8. Factor Analysis of Low-Frequency Repetitive Transcranial Magnetic Stimulation to the Temporoparietal Junction for Tinnitus

    Directory of Open Access Journals (Sweden)

    Hui Wang

    2016-01-01

    Full Text Available Objectives. We investigated factors that contribute to suppression of tinnitus after repetitive transcranial magnetic stimulation (rTMS. Methods. A total of 289 patients with tinnitus underwent active 1 Hz rTMS in the left temporoparietal region. A visual analog scale (VAS was used to assess tinnitus loudness. All participants were interviewed regarding age, gender, tinnitus duration, laterality and pitch, audiometric parameters, sleep, and so forth. The resting motor thresholds (RMTs were measured in all patients and 30 age- and gender-matched volunteers. Results. With respect to different factors that contribute to tinnitus suppression, we found improvement in the following domains: shorter duration, normal hearing (OR: 3.25, 95%CI: 2.01–5.27, p=0.001, and without sleep disturbance (OR: 2.51, 95%CI: 1.56–4.1, p=0.005 adjusted for age and gender. The patients with tinnitus lasting less than 1 year were more likely to show suppression of tinnitus (OR: 2.77, 95%CI: 1.48–5.19, p=0.002 compared to those with tinnitus lasting more than 5 years. Tinnitus patients had significantly lower RMTs compared with healthy volunteers. Conclusion. Active low-frequency rTMS results in a significant reduction in the loudness of tinnitus. Significant tinnitus suppression was shown in subjects with shorter tinnitus duration, with normal hearing, and without sleep disturbance.

  9. Transcutaneous electrical nerve stimulation (TENS) for pain control after vaginal delivery and cesarean section.

    Science.gov (United States)

    Kayman-Kose, Seda; Arioz, Dagistan Tolga; Toktas, Hasan; Koken, Gulengul; Kanat-Pektas, Mine; Kose, Mesut; Yilmazer, Mehmet

    2014-10-01

    The present study aims to determine the efficiency and reliability of transcutaneous electrical nerve stimulation (TENS) in the management of pain related with uterine contractions after vaginal delivery and the pain related with both abdominal incision uterine contractions after cesarean section. A hundred healthy women who underwent cesarean section under general anesthesia were randomly assigned to the placebo group (Group 1) or the TENS group (Group 2), while 100 women who delivered by vaginal route without episiotomy were randomized into the placebo group (Group 3) or the TENS group (Group 4). The patients in Group 2 had statistically lower visual analog scale (VAS) and verbal numerical scale (VNS) scores than the patients in Group 1 (p TENS (p = 0.006). The need for analgesics at the eighth hour of vaginal delivery was statistically similar in the patients who were treated with TENS and the patients who received placebo (p = 0.830). TENS is an effective, reliable, practical and easily available modality of treatment for postpartum pain.

  10. Effect of repetitive transcranial magnetic stimulation on mood in healthy subjects

    Directory of Open Access Journals (Sweden)

    Virginie Moulier

    2016-03-01

    Full Text Available Background: High frequency repetitive transcranial magnetic stimulation (rTMS of the left dorsolateral prefrontal cortex (DLPFC has shown significant efficiency in the treatment of resistant depression. However in healthy subjects, the effects of rTMS remain unclear. Objective: Our aim was to determine the impact of 10 sessions of rTMS applied to the DLPFC on mood and emotion recognition in healthy subjects. Design: In a randomised double-blind study, 20 subjects received 10 daily sessions of active (10 Hz frequency or sham rTMS. The TMS coil was positioned on the left DLPFC through neuronavigation. Several dimensions of mood and emotion processing were assessed at baseline and after rTMS with clinical scales, visual analogue scales (VASs, and the Ekman 60 faces test. Results: The 10 rTMS sessions targeting the DLPFC were well tolerated. No significant difference was found between the active group and the control group for clinical scales and the Ekman 60 faces test. Compared to the control group, the active rTMS group presented a significant improvement in their adaptation to daily life, which was assessed through VAS. Conclusion: This study did not show any deleterious effect on mood and emotion recognition of 10 sessions of rTMS applied on the DLPFC in healthy subjects. This study also suggested a positive effect of rTMS on quality of life.

  11. The Use of Transcutaneous Electrical Nerve Stimulation After Total Knee Arthroplasty: A Prospective Randomized Controlled Trial.

    Science.gov (United States)

    Ramanathan, Deepak; Saleh, Anas; Klika, Alison K; Higuera, Carlos A; Barsoum, Wael K

    2017-07-25

    Multimodal pain management is used after total knee arthroplasty (TKA) to reduce opioid intake. Transcutaneous electrical nerve stimulation (TENS) has generated much interest as a non-pharmacologic, patient-controlled therapy. The aims of this study were to evaluate the efficacy of TENS in reducing opioid intake and improving recovery after TKA. This was a prospective, parallel-group, double-blinded, randomized trial of patients receiving femoral nerve catheter block with allocation to either active or placebo TENS device groups. All participants were 18-85 years and underwent unilateral, primary TKA at two academic hospitals. Device usage was monitored during inpatient and outpatient phases. Participants were requested to return at second, fourth, and sixth postoperative weeks for follow-up. The primary endpoint was opioid usage, as indicated by medication intake in equianalgesic equivalents to morphine. Secondary measures included: visual analogue scale (VAS) pain scores; functional assessments as measured from knee joint range of motion (ROM) and Timed Up and Go (TUG) test; and clinical outcomes as defined by modified Knee injury and Osteoarthritis Outcome Scores (KOOS) and the 12-item Short Form Survey Instrument (SF-12). Among 116 participants, overall withdrawal was 37.9% (44 patients) at similar rates in both study arms. After excluding for non-femoral nerve catheter (FNC) blocks (i.e., protocol deviations), there were 35 patients in the active group and 31 patients in the placebo group whose complete records were analyzed. There were no significant differences between groups in any of the clinical endpoints.

  12. Multisensory stimulation in stroke rehabilitation

    Directory of Open Access Journals (Sweden)

    Barbro Birgitta Johansson

    2012-04-01

    Full Text Available The brain has a large capacity for automatic simultaneous processing and integration of sensory information. Combining information from different sensory modalities facilitates our ability to detect, discriminate, and recognize sensory stimuli, and learning is often optimal in a multisensory environment. Currently used multisensory stimulation methods in stroke rehabilitation include motor imagery, action observation, training with a mirror or in a virtual environment, or various kinds of music therapy. Several studies have shown positive effects been reported but to give general recommendation more studies are needed. Patient heterogeneity and the interactions of age, gender, genes and environment are discussed. Randomized controlled longitudinal trials starting earlier post stroke are needed. The advance in brain network science and neuroimaging enabling longitudinal studies of structural and functional networks are likely to have an important impact on patient selection for specific interventions in future stroke rehabilitation.

  13. Non-invasive neural stimulation

    Science.gov (United States)

    Tyler, William J.; Sanguinetti, Joseph L.; Fini, Maria; Hool, Nicholas

    2017-05-01

    Neurotechnologies for non-invasively interfacing with neural circuits have been evolving from those capable of sensing neural activity to those capable of restoring and enhancing human brain function. Generally referred to as non-invasive neural stimulation (NINS) methods, these neuromodulation approaches rely on electrical, magnetic, photonic, and acoustic or ultrasonic energy to influence nervous system activity, brain function, and behavior. Evidence that has been surmounting for decades shows that advanced neural engineering of NINS technologies will indeed transform the way humans treat diseases, interact with information, communicate, and learn. The physics underlying the ability of various NINS methods to modulate nervous system activity can be quite different from one another depending on the energy modality used as we briefly discuss. For members of commercial and defense industry sectors that have not traditionally engaged in neuroscience research and development, the science, engineering and technology required to advance NINS methods beyond the state-of-the-art presents tremendous opportunities. Within the past few years alone there have been large increases in global investments made by federal agencies, foundations, private investors and multinational corporations to develop advanced applications of NINS technologies. Driven by these efforts NINS methods and devices have recently been introduced to mass markets via the consumer electronics industry. Further, NINS continues to be explored in a growing number of defense applications focused on enhancing human dimensions. The present paper provides a brief introduction to the field of non-invasive neural stimulation by highlighting some of the more common methods in use or under current development today.

  14. Acupuncture-Point Stimulation for Postoperative Pain Control: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

    Science.gov (United States)

    Liu, Xian-Liang; Tan, Jing-Yu; Molassiotis, Alex; Suen, Lorna K. P.; Shi, Yan

    2015-01-01

    The purpose of this study was to evaluate the effectiveness of Acupuncture-point stimulation (APS) in postoperative pain control compared with sham/placebo acupuncture or standard treatments (usual care or no treatment). Only randomized controlled trials (RCTs) were included. Meta-analysis results indicated that APS interventions improved VAS scores significantly and also reduced total morphine consumption. No serious APS-related adverse effects (AEs) were reported. There is Level I evidence for the effectiveness of body points plaster therapy and Level II evidence for body points electroacupuncture (EA), body points acupressure, body points APS for abdominal surgery patients, auricular points seed embedding, manual auricular acupuncture, and auricular EA. We obtained Level III evidence for body points APS in patients who underwent cardiac surgery and cesarean section and for auricular-point stimulation in patients who underwent abdominal surgery. There is insufficient evidence to conclude that APS is an effective postoperative pain therapy in surgical patients, although the evidence does support the conclusion that APS can reduce analgesic requirements without AEs. The best level of evidence was not adequate in most subgroups. Some limitations of this study may have affected the results, possibly leading to an overestimation of APS effects. PMID:26568767

  15. Acupuncture-Point Stimulation for Postoperative Pain Control: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

    Directory of Open Access Journals (Sweden)

    Xian-Liang Liu

    2015-01-01

    Full Text Available The purpose of this study was to evaluate the effectiveness of Acupuncture-point stimulation (APS in postoperative pain control compared with sham/placebo acupuncture or standard treatments (usual care or no treatment. Only randomized controlled trials (RCTs were included. Meta-analysis results indicated that APS interventions improved VAS scores significantly and also reduced total morphine consumption. No serious APS-related adverse effects (AEs were reported. There is Level I evidence for the effectiveness of body points plaster therapy and Level II evidence for body points electroacupuncture (EA, body points acupressure, body points APS for abdominal surgery patients, auricular points seed embedding, manual auricular acupuncture, and auricular EA. We obtained Level III evidence for body points APS in patients who underwent cardiac surgery and cesarean section and for auricular-point stimulation in patients who underwent abdominal surgery. There is insufficient evidence to conclude that APS is an effective postoperative pain therapy in surgical patients, although the evidence does support the conclusion that APS can reduce analgesic requirements without AEs. The best level of evidence was not adequate in most subgroups. Some limitations of this study may have affected the results, possibly leading to an overestimation of APS effects.

  16. Mimicking muscle activity with electrical stimulation

    Science.gov (United States)

    Johnson, Lise A.; Fuglevand, Andrew J.

    2011-02-01

    Functional electrical stimulation is a rehabilitation technology that can restore some degree of motor function in individuals who have sustained a spinal cord injury or stroke. One way to identify the spatio-temporal patterns of muscle stimulation needed to elicit complex upper limb movements is to use electromyographic (EMG) activity recorded from able-bodied subjects as a template for electrical stimulation. However, this requires a transfer function to convert the recorded (or predicted) EMG signals into an appropriate pattern of electrical stimulation. Here we develop a generalized transfer function that maps EMG activity into a stimulation pattern that modulates muscle output by varying both the pulse frequency and the pulse amplitude. We show that the stimulation patterns produced by this transfer function mimic the active state measured by EMG insofar as they reproduce with good fidelity the complex patterns of joint torque and joint displacement.

  17. A Chip for an Implantable Neural Stimulator

    DEFF Research Database (Denmark)

    Gudnason, Gunnar; Bruun, Erik; Haugland, Morten

    2000-01-01

    This paper describes a chip for a multichannel neural stimulator for functional electrical stimulation (FES). The purpose of FES is to restore muscular control in disabled patients. The chip performs all the signal processing required in an implanted neural stimulator. The power and digital data...... transmission to the stimulator passes through a 5 MHz inductive link. From the signals transmitted to the stimulator, the chip is able to generate charge-balanced current pulses with a controllable length up to 256 µs and an amplitude up to 2 mA, for stimulation of nerve fibers. The quiescent current...... consumption of the chip is approx. 650 µA at supply voltages of 6–12 V, and its size is 3.9×3.5 mm2. It has 4 output channels for use in a multipolar cuff electrode....

  18. Analysis of Facial Expression by Taste Stimulation

    Science.gov (United States)

    Tobitani, Kensuke; Kato, Kunihito; Yamamoto, Kazuhiko

    In this study, we focused on the basic taste stimulation for the analysis of real facial expressions. We considered that the expressions caused by taste stimulation were unaffected by individuality or emotion, that is, such expressions were involuntary. We analyzed the movement of facial muscles by taste stimulation and compared real expressions with artificial expressions. From the result, we identified an obvious difference between real and artificial expressions. Thus, our method would be a new approach for facial expression recognition.

  19. VAGUS NERVE STIMULATION INHIBITS CORTICAL SPREADING DEPRESSION

    OpenAIRE

    Chen, Shih-Pin; Ay, Ilknur; de Morais, Andreia Lopes; Qin, Tao; Zheng,Yi; Sadhegian, Homa; Oka, Fumiaki; Simon, Bruce; Eikermann-Haerter, Katharina; Ayata, Cenk

    2016-01-01

    Vagus nerve stimulation has recently been reported to improve symptoms of migraine. Cortical spreading depression is the electrophysiological event underlying migraine aura, and a trigger for headache. We tested whether vagus nerve stimulation inhibits cortical spreading depression to explain its anti-migraine effect. Vagus nerve stimulation was delivered either non-invasively through the skin or directly by electrodes placed around the vagus nerve unilaterally. Systemic physiology was monito...

  20. Dorsal Root Ganglion (DRG) Stimulation in the Treatment of Phantom Limb Pain (PLP).

    Science.gov (United States)

    Eldabe, Sam; Burger, Katja; Moser, Heinrich; Klase, Daniel; Schu, Stefan; Wahlstedt, Anders; Vanderick, Bernard; Francois, Eric; Kramer, Jeffery; Subbaroyan, Jeyakumar

    2015-10-01

    Phantom limb pain (PLP) is a neuropathic condition in which pain is perceived as arising from an amputated limb. PLP is distinct from, although associated with, pain in the residual limb and nonpainful phantom sensations of the missing limb. Its treatment is extremely challenging; pharmaceutical options, while commonly employed, may be insufficient or intolerable. Neuromodulatory interventions such as spinal cord stimulation have generated mixed results and may be limited by poor somatotopic specificity. It was theorized that dorsal root ganglion (DRG) neuromodulation may be more effective. Patients trialed a DRG neurostimulation system for their PLP and were subsequently implanted if results were positive. Retrospective chart review was completed, including pain ratings on a 100-mm visual analogue scale (VAS) and patient-reported outcomes. Across eight patients, the average baseline pain rating was 85.5 mm. At follow-up (mean of 14.4 months), pain was rated at 43.5 mm. Subjective ratings of quality of life and functional capacity improved. Some patients reduced or eliminated pain medications. Patients reported precise concordance of the paresthesia with painful regions, including in their phantom limbs; in one case, stimulation eliminated PLP as well as nonpainful phantom sensations. Three patients experienced a diminution of pain relief, despite good initial outcomes. DRG neuromodulation may be an effective tool in treating this pain etiology. Clinical outcomes in this report support recent converging evidence suggesting that the DRG may be the site of PLP generation and/or maintenance. Further research is warranted to elucidate mechanisms and optimal treatment pathways. © 2015 International Neuromodulation Society.

  1. Skinfold thickness affects the isometric knee extension torque evoked by Neuromuscular Electrical Stimulation

    Directory of Open Access Journals (Sweden)

    Flávia V. A. Medeiros

    2015-12-01

    Full Text Available BACKGROUND: Subcutaneous adipose tissue may influence the transmission of electrical stimuli through to the skin, thus affecting both evoked torque and comfort perception associated with neuromuscular electrical stimulation (NMES. This could seriously affect the effectiveness of NMES for either rehabilitation or sports purposes. OBJECTIVE: To investigate the effects of skinfold thickness (SFT on maximal NMES current intensity, NMES-evoked torque, and NMES-induced discomfort. METHOD: First, we compared NMES current intensity, NMES-induced discomfort, and NMES-evoked torque between two subgroups of subjects with thicker (n=10; 20.7 mm vs. thinner (n=10; 29.4 mm SFT. Second, we correlated SFT to NMES current intensity, NMES-induced discomfort, and NMES-evoked knee extension torque in 20 healthy women. The NMES-evoked torque was normalized to the maximal voluntary contraction (MVC torque. The discomfort induced by NMES was assessed with a visual analog scale (VAS. RESULTS: NMES-evoked torque was 27.5% lower in subjects with thicker SFT (p=0.01 while maximal current intensity was 24.2% lower in subjects with thinner SFT (p=0.01. A positive correlation was found between current intensity and SFT (r=0.540, p=0.017. A negative correlation was found between NMES-evoked torque and SFT (r=-0.563, p=0.012. No significant correlation was observed between discomfort scores and SFT (rs=0.15, p=0.53. CONCLUSION: These results suggest that the amount of subcutaneous adipose tissue (as reflected by skinfold thickness affected NMES current intensity and NMES-evoked torque, but had no effect on discomfort perception. Our findings may help physical therapists to better understand the impact of SFT on NMES and to design more rational stimulation strategies.

  2. Vestibular Stimulation for Stress Management in Students.

    Science.gov (United States)

    Kumar, Sai Sailesh; Rajagopalan, Archana; Mukkadan, Joseph Kurien

    2016-02-01

    Although several methods are developed to alleviate stress among college students, logistic limitations in adopting them have limited their utility. Hence, we aimed to test a very practical approach to alleviate stress among college students by achieving vestibular stimulation using swings. In this study 60 male and female participants were randomly assigned into vestibular stimulation or control groups. Depression, anxiety, stress scores, sleep quality, heart rate, blood pressure, Autonomic functions, respiratory, haematological, cognitive function, Quality of life were recorded before and after 1(st), 7(th), 14(th), 21(st), 28(th) days of vestibular stimulation. STAI S and STAI T scores were significantly improved on day 28(th) following vestibular stimulation. Diastolic and mean arterial blood pressure were significantly decreased and remained within normal limits in vestibular group on day 28(th) following vestibular stimulation. Postural fall in blood pressure was significantly improved on day 14 onwards, following vestibular stimulation. Respiratory rate was significantly improved on day 7 onwards, following vestibular stimulation. PSQI sleep disturbance, PSQI sleep latency, PSQI total score and bleeding time was significantly improved following vestibular stimulation. Our study supports the adoption of vestibular stimulation for stress management. Hence, placement of swings in college campuses must be considered, which may be a simple approach to alleviate stress among college students.

  3. Vagus nerve stimulation inhibits cortical spreading depression.

    Science.gov (United States)

    Chen, Shih-Pin; Ay, Ilknur; de Morais, Andreia Lopes; Qin, Tao; Zheng, Yi; Sadeghian, Homa; Oka, Fumiaki; Simon, Bruce; Eikermann-Haerter, Katharina; Ayata, Cenk

    2016-04-01

    Vagus nerve stimulation has recently been reported to improve symptoms of migraine. Cortical spreading depression is the electrophysiological event underlying migraine aura and is a trigger for headache. We tested whether vagus nerve stimulation inhibits cortical spreading depression to explain its antimigraine effect. Unilateral vagus nerve stimulation was delivered either noninvasively through the skin or directly by electrodes placed around the nerve. Systemic physiology was monitored throughout the study. Both noninvasive transcutaneous and invasive direct vagus nerve stimulations significantly suppressed spreading depression susceptibility in the occipital cortex in rats. The electrical stimulation threshold to evoke a spreading depression was elevated by more than 2-fold, the frequency of spreading depressions during continuous topical 1 M KCl was reduced by ∼40%, and propagation speed of spreading depression was reduced by ∼15%. This effect developed within 30 minutes after vagus nerve stimulation and persisted for more than 3 hours. Noninvasive transcutaneous vagus nerve stimulation was as efficacious as direct invasive vagus nerve stimulation, and the efficacy did not differ between the ipsilateral and contralateral hemispheres. Our findings provide a potential mechanism by which vagus nerve stimulation may be efficacious in migraine and suggest that susceptibility to spreading depression is a suitable platform to optimize its efficacy.

  4. Ovarian Stimulation and the Endometrium: New Approaches and Insights

    NARCIS (Netherlands)

    M.H. van der Gaast (Mark)

    2009-01-01

    textabstractWhen one considers the recognized 'causes' of infertility, problems with gamete quality and availability rank highly, as does the means of their transport, whether it be through the fallopian tubes in the female or vas deferens in the male. Conception is seen as the primary goal, and

  5. Cognitive stimulation in healthy older adults: a cognitive stimulation program using leisure activities compared to a conventional cognitive stimulation program.

    Science.gov (United States)

    Grimaud, Élisabeth; Taconnat, Laurence; Clarys, David

    2017-06-01

    The aim of this study was to compare two methods of cognitive stimulation for the cognitive functions. The first method used an usual approach, the second used leisure activities in order to assess their benefits on cognitive functions (speed of processing; working memory capacity and executive functions) and psychoaffective measures (memory span and self esteem). 67 participants over 60 years old took part in the experiment. They were divided into three groups: 1 group followed a program of conventional cognitive stimulation, 1 group a program of cognitive stimulation using leisure activities and 1 control group. The different measures have been evaluated before and after the training program. Results show that the cognitive stimulation program using leisure activities is as effective on memory span, updating and memory self-perception as the program using conventional cognitive stimulation, and more effective on self-esteem than the conventional program. There is no difference between the two stimulated groups and the control group on speed of processing. Neither of the two cognitive stimulation programs provides a benefit over shifting and inhibition. These results indicate that it seems to be possible to enhance working memory and to observe far transfer benefits over self-perception (self-esteem and memory self-perception) when using leisure activities as a tool for cognitive stimulation.

  6. Repetitive transcranial magnetic stimulation is efficacious as an add-on to pharmacological therapy in complex regional pain syndrome (CRPS) type I.

    Science.gov (United States)

    Picarelli, Helder; Teixeira, Manoel Jacobsen; de Andrade, Daniel Ciampi; Myczkowski, Martin Luiz; Luvisotto, Tatiana Barreira; Yeng, Lin Tchia; Fonoff, Erich Talamoni; Pridmore, Saxby; Marcolin, Marco Antonio

    2010-11-01

    Single-session repetitive transcranial magnetic stimulation (rTMS) of the motor cortex (M1) is effective in the treatment of chronic pain patients, but the analgesic effect of repeated sessions is still unknown. We evaluated the effects of rTMS in patients with refractory pain due to complex regional pain syndrome (CRPS) type I. Twenty-three patients presenting CRPS type I of 1 upper limb were treated with the best medical treatment (analgesics and adjuvant medications, physical therapy) plus 10 daily sessions of either real (r-) or sham (s-) 10 Hz rTMS to the motor cortex (M1). Patients were assessed daily and after 1 week and 3 months after the last session using the Visual Analogical Scale (VAS), the McGill Pain Questionnaire (MPQ), the Health Survey-36 (SF-36), and the Hamilton Depression (HDRS). During treatment there was a significant reduction in the VAS scores favoring the r-rTMS group, mean reduction of 4.65 cm (50.9%) against 2.18 cm (24.7%) in the s-rTMS group. The highest reduction occurred at the tenth session and correlated to improvement in the affective and emotional subscores of the MPQ and SF-36. Real rTMS to the M1 produced analgesic effects and positive changes in affective aspects of pain in CRPS patients during the period of stimulation. This study shows an efficacy of repetitive sessions of high-frequency rTMS as an add-on therapy to refractory CRPS type I patients. It had a positive effect in different aspects of pain (sensory-discriminative and emotional-affective). It opens the perspective for the clinical use of this technique. Copyright © 2010 American Pain Society. Published by Elsevier Inc. All rights reserved.

  7. Neuroplastic effects of transcranial direct current stimulation on painful symptoms reduction in chronic Hepatitis C: a phase II randomized, double blind, sham controlled trial

    Directory of Open Access Journals (Sweden)

    Aline Patricia Brietzke

    2016-01-01

    Full Text Available Introduction: Pegylated Interferon Alpha (Peg-IFN in combination with other drugs is the standard treatment for chronic hepatitis C infection (HCV and is related to severe painful symptoms. The aim of this study was access the efficacy of transcranial direct current stimulation (tDCS in controlling the painful symptoms related to Peg-IFN side effects. Material and Methods: In this phase II double-blind trial, twenty eight (n=28 HCV subjects were randomized to receive either five consecutive days of active tDCS (n=14 or sham (n=14 during five consecutive days with anodal stimulation over the primary motor cortex region using 2 mA for 20 minutes. The primary outcomes were visual analogue scale (VAS pain and brain-derived neurotrophic factor (BDNF serum levels. Secondary outcomes were the pressure-pain threshold (PPT, the Brazilian Profile of Chronic Pain: Screen (B-PCP:S and drug analgesics use. Results: tDCS reduced the VAS scores (P<0.003, with a mean pain drop of 56% (p<0.001. Furthermore, tDCS was able to enhance BDNF levels (p<0.01. The mean increase was 37.48% in the active group. Finally, tDCS raised PPT (p<0.001 and reduced the B-PCP:S scores and analgesic use (p<0.05. Conclusions: Five sessions of tDCS were effective in reducing the painful symptoms in HCV patients undergoing Peg-IFN treatment. These findings support the efficacy of tDCS as a promising therapeutic tool to improve the tolerance of the side effects related to the use of Peg-IFN. Future larger studies (phase III and IV trials are needed to confirm the clinical use of the therapeutic effects of tDCS in such condition. Trial registration: Brazilian Human Health Regulator for Research with the approval number CAAE 07802012.0.0000.5327

  8. Is Preoperative Pain Duration Important in Spinal Cord Stimulation? A Comparison Between Tonic and Burst Stimulation

    NARCIS (Netherlands)

    de Ridder, D.; Vancamp, T.; Lenders, M.W.P.M.; de Vos, Cecilia Cecilia Clementine; Vanneste, J.

    2015-01-01

    Objective Conflicting data have been published as to whether the success rate of spinal cord stimulation (SCS) is inversely proportional to the time interval from the initial onset of symptoms to implantation. Recently, a new stimulation design called burst stimulation has been developed that seems

  9. Swelling of rat hepatocytes stimulates glycogen synthesis

    NARCIS (Netherlands)

    Baquet, A.; Hue, L.; Meijer, A. J.; van Woerkom, G. M.; Plomp, P. J.

    1990-01-01

    In hepatocytes from fasted rats, several amino acids are known to stimulate glycogen synthesis via activation of glycogen synthase. The hypothesis that an increase in cell volume resulting from amino acid uptake may be involved in the stimulation of glycogen synthesis is supported by the following

  10. Consensus paper: combining transcranial stimulation with neuroimaging

    DEFF Research Database (Denmark)

    Siebner, Hartwig R; Bergmann, Til O; Bestmann, Sven

    2009-01-01

    In the last decade, combined transcranial magnetic stimulation (TMS)-neuroimaging studies have greatly stimulated research in the field of TMS and neuroimaging. Here, we review how TMS can be combined with various neuroimaging techniques to investigate human brain function. When applied during ne...

  11. Modeling bipolar stimulation of cardiac tissue

    Science.gov (United States)

    Galappaththige, Suran K.; Gray, Richard A.; Roth, Bradley J.

    2017-09-01

    Unipolar stimulation of cardiac tissue is often used in the design of cardiac pacemakers because of the low current required to depolarize the surrounding tissue at rest. However, the advantages of unipolar over bipolar stimulation are not obvious at shorter coupling intervals when the tissue near the pacing electrode is relatively refractory. Therefore, this paper analyzes bipolar stimulation of cardiac tissue. The strength-interval relationship for bipolar stimulation is calculated using the bidomain model and a recently developed parsimonious ionic current model. The strength-interval curves obtained using different electrode separations and arrangements (electrodes placed parallel to the fibers versus perpendicular to the fibers) indicate that bipolar stimulation results in more complex activation patterns compared to unipolar stimulation. An unusually low threshold stimulus current is observed when the electrodes are close to each other (a separation of 1 mm) because of break excitation. Unlike for unipolar stimulation, anode make excitation is not present during bipolar stimulation, and an abrupt switch from anode break to cathode make excitation can cause dramatic changes in threshold with very small changes in the interval. These results could impact the design of implantable pacemakers and defibrillators.

  12. Wirelessly powering miniature implants for optogenetic stimulation

    Science.gov (United States)

    Yeh, Alexander J.; Ho, John S.; Tanabe, Yuji; Neofytou, Evgenios; Beygui, Ramin E.; Poon, Ada S. Y.

    2013-10-01

    Conventional methods for in vivo optogenetic stimulation require optical fibers or mounted prosthesis. We present an approach for wirelessly powering implantable stimulators using electromagnetic midfield. By exploiting the properties of the midfield, we demonstrate the ability to generate high intensity light pulses in a freely moving animal.

  13. Electrocutaneous stimulation system for Braille reading.

    Science.gov (United States)

    Echenique, Ana Maria; Graffigna, Juan Pablo; Mut, Vicente

    2010-01-01

    This work is an assistive technology for people with visual disabilities and aims to facilitate access to written information in order to achieve better social inclusion and integration into work and educational activities. Two methods of electrical stimulation (by current and voltage) of the mechanoreceptors was tested to obtain tactile sensations on the fingertip. Current and voltage stimulation were tested in a Braille cell and line prototype, respectively. These prototypes are evaluated in 33 blind and visually impaired subjects. The result of experimentation with both methods showed that electrical stimulation causes sensations of touch defined in the fingertip. Better results in the Braille characters reading were obtained with current stimulation (85% accuracy). However this form of stimulation causes uncomfortable sensations. The latter feeling was minimized with the method of voltage stimulation, but with low efficiency (50% accuracy) in terms of identification of the characters. We concluded that electrical stimulation is a promising method for the development of a simple and unexpensive Braille reading system for blind people. We observed that voltage stimulation is preferred by the users. However, more experimental tests must be carry out in order to find the optimum values of the stimulus parameters and increase the accuracy the Braille characters reading.

  14. Questions That Stimulate Creativity and Innovation.

    Science.gov (United States)

    Kowalski, Karren

    2017-03-01

    A higher level of questioning can stimulate creativity and innovation. Stimulating innovation and change in health care is critical to advancing care delivered by nurses and the necessary changes in the systems housing this care. Staff development faculty can teach nurses how to ask these questions. J Contin Educ Nurs. 2017;48(3):102-103. Copyright 2017, SLACK Incorporated.

  15. Deep brain stimulation in Parkinson's disease

    OpenAIRE

    Dowsey-Limousin, P.; Fraix, V.; Benabid, A. L.; Pollak, P.

    2001-01-01

    During the last 15 years deep brain stimulation (DBS) has been established as a highly-effective therapy for advanced Parkinson's disease (PD). Patient selection, stereotactic implantation, postoperative stimulator programming and patient care requires a multi-disciplinary team including movement disorders specialists in neurology and functional neurosurgery. To treat medically r...

  16. Violet stimulated luminescence: geo- or thermochronometer?

    DEFF Research Database (Denmark)

    Ankjærgaard, Christina; Guralnik, Benny; Porat, N.

    2015-01-01

    The method of quartz optically stimulated luminescence (OSL) dating is widely used, but generally limited to the past ~0.1 million years (Ma) due to early saturation of the desired signal. Violet stimulated luminescence (VSL) of quartz has previously been shown as a promising alternative, with a ...

  17. Are Prescription Stimulants “Smart Pills”?

    Science.gov (United States)

    Smith, M. Elizabeth; Farah, Martha J.

    2013-01-01

    Use of prescription stimulants by normal healthy individuals to enhance cognition is said to be on the rise. Who is using these medications for cognitive enhancement, and how prevalent is this practice? Do prescription stimulants in fact enhance cognition for normal healthy people? We review the epidemiological and cognitive neuroscience literatures in search of answers to these questions. Epidemiological issues addressed include the prevalence of nonmedical stimulant use, user demographics, methods by which users obtain prescription stimulants, and motivations for use. Cognitive neuroscience issues addressed include the effects of prescription stimulants on learning and executive function, as well as the task and individual variables associated with these effects. Little is known about the prevalence of prescription stimulant use for cognitive enhancement outside of student populations. Among college students, estimates of use vary widely but, taken together, suggest that the practice is commonplace. The cognitive effects of stimulants on normal healthy people cannot yet be characterized definitively, despite the volume of research that has been carried out on these issues. Published evidence suggests that declarative memory can be improved by stimulants, with some evidence consistent with enhanced consolidation of memories. Effects on the executive functions of working memory and cognitive control are less reliable but have been found for at least some individuals on some tasks. In closing, we enumerate the many outstanding questions that remain to be addressed by future research and also identify obstacles facing this research. PMID:21859174

  18. Twiddler's syndrome in spinal cord stimulation.

    Science.gov (United States)

    Al-Mahfoudh, Rafid; Chan, Yuen; Chong, Hsu Pheen; Farah, Jibril Osman

    2016-01-01

    The aims are to present a case series of Twiddler's syndrome in spinal cord stimulators with analysis of the possible mechanism of this syndrome and discuss how this phenomenon can be prevented. Data were collected retrospectively between 2007 and 2013 for all patients presenting with failure of spinal cord stimulators. The diagnostic criterion for Twiddler's syndrome is radiological evidence of twisting of wires in the presence of failure of spinal cord stimulation. Our unit implants on average 110 spinal cord stimulators a year. Over the 5-year study period, all consecutive cases of spinal cord stimulation failure were studied. Three patients with Twiddler's syndrome were identified. Presentation ranged from 4 to 228 weeks after implantation. Imaging revealed repeated rotations and twisting of the wires of the spinal cord stimulators leading to hardware failure. To the best of our knowledge this is the first reported series of Twiddler's syndrome with implantable pulse generators (IPGs) for spinal cord stimulation. Hardware failure is not uncommon in spinal cord stimulation. Awareness and identification of Twiddler's syndrome may help prevent its occurrence and further revisions. This may be achieved by implanting the IPG in the lumbar region subcutaneously above the belt line. Psychological intervention may have a preventative role for those who are deemed at high risk of Twiddler's syndrome from initial psychological screening.

  19. Vagus nerve stimulation in clinical practice.

    Science.gov (United States)

    Farmer, Adam D; Albu-Soda, Ahmed; Aziz, Qasim

    2016-11-02

    The diverse array of end organ innervations of the vagus nerve, coupled with increased basic science evidence, has led to vagus nerve stimulation becoming a management option in a number of clinical disorders. This review discusses methods of electrically stimulating the vagus nerve and its current and potential clinical uses.

  20. Kinetics of infrared stimulated luminescence from feldspars

    DEFF Research Database (Denmark)

    Jain, Mayank; Sohbati, Reza; Guralnik, Benny

    2015-01-01

    thermal and optical, of the infrared stimulated luminescence signal from feldspar. Based on the application of this model, it is concluded that different infra-red stimulated luminescence emissions (UV, blue, yellow and far-red) follow the same kinetics, and, therefore, involve participation of the same...